text: /* Copyright (c) 2001-2004, Roger Dingledine.
   * Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson.
   * Copyright (c) 2007-2019, The Tor Project, Inc. */
  /* See LICENSE for licensing information */
  
  #define DIRVOTE_PRIVATE
  #include "core/or/or.h"
  #include "app/config/config.h"
  #include "core/or/policies.h"
  #include "core/or/protover.h"
  #include "core/or/tor_version_st.h"
  #include "core/or/versions.h"
  #include "feature/dirauth/bwauth.h"
  #include "feature/dirauth/dircollate.h"
  #include "feature/dirauth/dsigs_parse.h"
  #include "feature/dirauth/guardfraction.h"
  #include "feature/dirauth/recommend_pkg.h"
  #include "feature/dirauth/voteflags.h"
  #include "feature/dircache/dirserv.h"
  #include "feature/dirclient/dirclient.h"
  #include "feature/dircommon/directory.h"
  #include "feature/dirparse/microdesc_parse.h"
  #include "feature/dirparse/ns_parse.h"
  #include "feature/dirparse/parsecommon.h"
  #include "feature/dirparse/signing.h"
  #include "feature/nodelist/authcert.h"
  #include "feature/nodelist/dirlist.h"
  #include "feature/nodelist/fmt_routerstatus.h"
  #include "feature/nodelist/microdesc.h"
  #include "feature/nodelist/networkstatus.h"
  #include "feature/nodelist/nodefamily.h"
  #include "feature/nodelist/nodelist.h"
  #include "feature/nodelist/routerlist.h"
  #include "feature/relay/router.h"
  #include "feature/relay/routerkeys.h"
  #include "feature/stats/rephist.h"
  #include "feature/client/entrynodes.h" /* needed for guardfraction methods */
  #include "feature/nodelist/torcert.h"
  #include "feature/dircommon/voting_schedule.h"
  
  #include "feature/dirauth/dirvote.h"
  #include "feature/dirauth/authmode.h"
  #include "feature/dirauth/shared_random_state.h"
  
  #include "feature/nodelist/authority_cert_st.h"
  #include "feature/dircache/cached_dir_st.h"
  #include "feature/dirclient/dir_server_st.h"
  #include "feature/nodelist/document_signature_st.h"
  #include "feature/nodelist/microdesc_st.h"
  #include "feature/nodelist/networkstatus_st.h"
  #include "feature/nodelist/networkstatus_voter_info_st.h"
  #include "feature/nodelist/node_st.h"
  #include "feature/dirauth/ns_detached_signatures_st.h"
  #include "feature/nodelist/routerinfo_st.h"
  #include "feature/nodelist/routerlist_st.h"
  #include "feature/dirauth/vote_microdesc_hash_st.h"
  #include "feature/nodelist/vote_routerstatus_st.h"
  #include "feature/dircommon/vote_timing_st.h"
  
  #include "lib/container/order.h"
  #include "lib/encoding/confline.h"
  #include "lib/crypt_ops/crypto_format.h"
  
  /* Algorithm to use for the bandwidth file digest. */
  #define DIGEST_ALG_BW_FILE DIGEST_SHA256
  
  /**
   * \file dirvote.c
   * \brief Functions to compute directory consensus, and schedule voting.
   *
   * This module is the center of the consensus-voting based directory
   * authority system.  With this system, a set of authorities first
   * publish vote based on their opinions of the network, and then compute
   * a consensus from those votes.  Each authority signs the consensus,
   * and clients trust the consensus if enough known authorities have
   * signed it.
   *
   * The code in this module is only invoked on directory authorities.  It's
   * responsible for:
   *
   * <ul>
   *   <li>Generating this authority's vote networkstatus, based on the
   *       authority's view of the network as represented in dirserv.c
   *   <li>Formatting the vote networkstatus objects.
   *   <li>Generating the microdescriptors that correspond to our own
   *       vote.
   *   <li>Sending votes to all the other authorities.
   *   <li>Trying to fetch missing votes from other authorities.
   *   <li>Computing the consensus from a set of votes, as well as
   *       a "detached signature" object for other authorities to fetch.
   *   <li>Collecting other authorities' signatures on the same consensus,
   *       until there are enough.
   *   <li>Publishing the consensus to the reset of the directory system.
   *   <li>Scheduling all of the above operations.
   * </ul>
   *
   * The main entry points are in dirvote_act(), which handles scheduled
   * actions; and dirvote_add_vote() and dirvote_add_signatures(), which
   * handle uploaded and downloaded votes and signatures.
   *
   * (See dir-spec.txt from torspec.git for a complete specification of
   * the directory protocol and voting algorithms.)
   **/
  
  /** A consensus that we have built and are appending signatures to.  Once it's
   * time to publish it, it will become an active consensus if it accumulates
   * enough signatures. */
  typedef struct pending_consensus_t {
    /** The body of the consensus that we're currently building.  Once we
     * have it built, it goes into dirserv.c */
    char *body;
    /** The parsed in-progress consensus document. */
    networkstatus_t *consensus;
  } pending_consensus_t;
  
  /* DOCDOC dirvote_add_signatures_to_all_pending_consensuses */
  static int dirvote_add_signatures_to_all_pending_consensuses(
                         const char *detached_signatures_body,
                         const char *source,
                         const char **msg_out);
  static int dirvote_add_signatures_to_pending_consensus(
                         pending_consensus_t *pc,
                         ns_detached_signatures_t *sigs,
                         const char *source,
                         int severity,
                         const char **msg_out);
  static char *list_v3_auth_ids(void);
  static void dirvote_fetch_missing_votes(void);
  static void dirvote_fetch_missing_signatures(void);
  static int dirvote_perform_vote(void);
  static void dirvote_clear_votes(int all_votes);
  static int dirvote_compute_consensuses(void);
  static int dirvote_publish_consensus(void);
  
  /* =====
   * Certificate functions
   * ===== */
  
  /** Allocate and return a new authority_cert_t with the same contents as
   * <b>cert</b>. */
  STATIC authority_cert_t *
  authority_cert_dup(authority_cert_t *cert)
  {
    authority_cert_t *out = tor_malloc(sizeof(authority_cert_t));
    tor_assert(cert);
  
    memcpy(out, cert, sizeof(authority_cert_t));
    /* Now copy pointed-to things. */
    out->cache_info.signed_descriptor_body =
      tor_strndup(cert->cache_info.signed_descriptor_body,
                  cert->cache_info.signed_descriptor_len);
    out->cache_info.saved_location = SAVED_NOWHERE;
    out->identity_key = crypto_pk_dup_key(cert->identity_key);
    out->signing_key = crypto_pk_dup_key(cert->signing_key);
  
    return out;
  }
  
  /* =====
   * Voting
   * =====*/
  
  /* If <b>opt_value</b> is non-NULL, return "keyword opt_value\n" in a new
   * string. Otherwise return a new empty string. */
  static char *
  format_line_if_present(const char *keyword, const char *opt_value)
  {
    if (opt_value) {
      char *result = NULL;
      tor_asprintf(&result, "%s %s\n", keyword, opt_value);
      return result;
    } else {
      return tor_strdup("");
    }
  }
  
  /** Format the recommended/required-relay-client protocols lines for a vote in
   * a newly allocated string, and return that string. */
  static char *
  format_protocols_lines_for_vote(const networkstatus_t *v3_ns)
  {
    char *recommended_relay_protocols_line = NULL;
    char *recommended_client_protocols_line = NULL;
    char *required_relay_protocols_line = NULL;
    char *required_client_protocols_line = NULL;
  
    recommended_relay_protocols_line =
      format_line_if_present("recommended-relay-protocols",
                             v3_ns->recommended_relay_protocols);
    recommended_client_protocols_line =
      format_line_if_present("recommended-client-protocols",
                             v3_ns->recommended_client_protocols);
    required_relay_protocols_line =
      format_line_if_present("required-relay-protocols",
                             v3_ns->required_relay_protocols);
    required_client_protocols_line =
      format_line_if_present("required-client-protocols",
                             v3_ns->required_client_protocols);
  
    char *result = NULL;
    tor_asprintf(&result, "%s%s%s%s",
                 recommended_relay_protocols_line,
                 recommended_client_protocols_line,
                 required_relay_protocols_line,
                 required_client_protocols_line);
  
    tor_free(recommended_relay_protocols_line);
    tor_free(recommended_client_protocols_line);
    tor_free(required_relay_protocols_line);
    tor_free(required_client_protocols_line);
  
    return result;
  }
  
  /** Return a new string containing the string representation of the vote in
   * <b>v3_ns</b>, signed with our v3 signing key <b>private_signing_key</b>.
   * For v3 authorities. */
  STATIC char *
  format_networkstatus_vote(crypto_pk_t *private_signing_key,
                            networkstatus_t *v3_ns)
  {
    smartlist_t *chunks = smartlist_new();
    char *packages = NULL;
    char fingerprint[FINGERPRINT_LEN+1];
    char digest[DIGEST_LEN];
    uint32_t addr;
    char *protocols_lines = NULL;
    char *client_versions_line = NULL, *server_versions_line = NULL;
    char *shared_random_vote_str = NULL;
    networkstatus_voter_info_t *voter;
    char *status = NULL;
  
    tor_assert(private_signing_key);
    tor_assert(v3_ns->type == NS_TYPE_VOTE || v3_ns->type == NS_TYPE_OPINION);
  
    voter = smartlist_get(v3_ns->voters, 0);
  
    addr = voter->addr;
  
    base16_encode(fingerprint, sizeof(fingerprint),
                  v3_ns->cert->cache_info.identity_digest, DIGEST_LEN);
  
    client_versions_line = format_line_if_present("client-versions",
                                                  v3_ns->client_versions);
    server_versions_line = format_line_if_present("server-versions",
                                                  v3_ns->server_versions);
    protocols_lines = format_protocols_lines_for_vote(v3_ns);
  
    if (v3_ns->package_lines) {
      smartlist_t *tmp = smartlist_new();
      SMARTLIST_FOREACH(v3_ns->package_lines, const char *, p,
                        if (validate_recommended_package_line(p))
                          smartlist_add_asprintf(tmp, "package %s\n", p));
      smartlist_sort_strings(tmp);
      packages = smartlist_join_strings(tmp, "", 0, NULL);
      SMARTLIST_FOREACH(tmp, char *, cp, tor_free(cp));
      smartlist_free(tmp);
    } else {
      packages = tor_strdup("");
    }
  
      /* Get shared random commitments/reveals line(s). */
    shared_random_vote_str = sr_get_string_for_vote();
  
    {
      char published[ISO_TIME_LEN+1];
      char va[ISO_TIME_LEN+1];
      char fu[ISO_TIME_LEN+1];
      char vu[ISO_TIME_LEN+1];
      char *flags = smartlist_join_strings(v3_ns->known_flags, " ", 0, NULL);
      /* XXXX Abstraction violation: should be pulling a field out of v3_ns.*/
      char *flag_thresholds = dirserv_get_flag_thresholds_line();
      char *params;
      char *bw_headers_line = NULL;
      char *bw_file_digest = NULL;
      authority_cert_t *cert = v3_ns->cert;
      char *methods =
        make_consensus_method_list(MIN_SUPPORTED_CONSENSUS_METHOD,
                                   MAX_SUPPORTED_CONSENSUS_METHOD, " ");
      format_iso_time(published, v3_ns->published);
      format_iso_time(va, v3_ns->valid_after);
      format_iso_time(fu, v3_ns->fresh_until);
      format_iso_time(vu, v3_ns->valid_until);
  
      if (v3_ns->net_params)
        params = smartlist_join_strings(v3_ns->net_params, " ", 0, NULL);
      else
        params = tor_strdup("");
      tor_assert(cert);
  
      /* v3_ns->bw_file_headers is only set when V3BandwidthsFile is
       * configured */
      if (v3_ns->bw_file_headers) {
        char *bw_file_headers = NULL;
        /* If there are too many headers, leave the header string NULL */
        if (! BUG(smartlist_len(v3_ns->bw_file_headers)
                  > MAX_BW_FILE_HEADER_COUNT_IN_VOTE)) {
          bw_file_headers = smartlist_join_strings(v3_ns->bw_file_headers, " ",
                                                   0, NULL);
          if (BUG(strlen(bw_file_headers) > MAX_BW_FILE_HEADERS_LINE_LEN)) {
            /* Free and set to NULL, because the line was too long */
            tor_free(bw_file_headers);
          }
        }
        if (!bw_file_headers) {
            /* If parsing failed, add a bandwidth header line with no entries */
            bw_file_headers = tor_strdup("");
        }
        /* At this point, the line will always be present */
        bw_headers_line = format_line_if_present("bandwidth-file-headers",
                                                 bw_file_headers);
        tor_free(bw_file_headers);
      }
  
      /* Create bandwidth-file-digest if applicable.
       * v3_ns->b64_digest_bw_file will contain the digest when V3BandwidthsFile
       * is configured and the bandwidth file could be read, even if it was not
       * parseable.
       */
      if (!tor_digest256_is_zero((const char *)v3_ns->bw_file_digest256)) {
        /* Encode the digest. */
        char b64_digest_bw_file[BASE64_DIGEST256_LEN+1] = {0};
        digest256_to_base64(b64_digest_bw_file,
                            (const char *)v3_ns->bw_file_digest256);
        /* "bandwidth-file-digest" 1*(SP algorithm "=" digest) NL */
        char *digest_algo_b64_digest_bw_file = NULL;
        tor_asprintf(&digest_algo_b64_digest_bw_file, "%s=%s",
                     crypto_digest_algorithm_get_name(DIGEST_ALG_BW_FILE),
                     b64_digest_bw_file);
        /* No need for tor_strdup(""), format_line_if_present does it. */
        bw_file_digest = format_line_if_present(
            "bandwidth-file-digest", digest_algo_b64_digest_bw_file);
        tor_free(digest_algo_b64_digest_bw_file);
      }
  
      smartlist_add_asprintf(chunks,
                   "network-status-version 3\n"
                   "vote-status %s\n"
                   "consensus-methods %s\n"
                   "published %s\n"
                   "valid-after %s\n"
                   "fresh-until %s\n"
                   "valid-until %s\n"
                   "voting-delay %d %d\n"
                   "%s%s" /* versions */
                   "%s" /* protocols */
                   "%s" /* packages */
                   "known-flags %s\n"
                   "flag-thresholds %s\n"
                   "params %s\n"
                   "%s" /* bandwidth file headers */
                   "%s" /* bandwidth file digest */
                   "dir-source %s %s %s %s %d %d\n"
                   "contact %s\n"
                   "%s" /* shared randomness information */
                   ,
                   v3_ns->type == NS_TYPE_VOTE ? "vote" : "opinion",
                   methods,
                   published, va, fu, vu,
                   v3_ns->vote_seconds, v3_ns->dist_seconds,
                   client_versions_line,
                   server_versions_line,
                   protocols_lines,
                   packages,
                   flags,
                   flag_thresholds,
                   params,
                   bw_headers_line ? bw_headers_line : "",
                   bw_file_digest ? bw_file_digest: "",
                   voter->nickname, fingerprint, voter->address,
                   fmt_addr32(addr), voter->dir_port, voter->or_port,
                   voter->contact,
                   shared_random_vote_str ?
                             shared_random_vote_str : "");
  
      tor_free(params);
      tor_free(flags);
      tor_free(flag_thresholds);
      tor_free(methods);
      tor_free(shared_random_vote_str);
      tor_free(bw_headers_line);
      tor_free(bw_file_digest);
  
      if (!tor_digest_is_zero(voter->legacy_id_digest)) {
        char fpbuf[HEX_DIGEST_LEN+1];
        base16_encode(fpbuf, sizeof(fpbuf), voter->legacy_id_digest, DIGEST_LEN);
        smartlist_add_asprintf(chunks, "legacy-dir-key %s\n", fpbuf);
      }
  
      smartlist_add(chunks, tor_strndup(cert->cache_info.signed_descriptor_body,
                                        cert->cache_info.signed_descriptor_len));
    }
  
    SMARTLIST_FOREACH_BEGIN(v3_ns->routerstatus_list, vote_routerstatus_t *,
                            vrs) {
      char *rsf;
      vote_microdesc_hash_t *h;
      rsf = routerstatus_format_entry(&vrs->status,
                                      vrs->version, vrs->protocols,
                                      NS_V3_VOTE,
                                      ROUTERSTATUS_FORMAT_NO_CONSENSUS_METHOD,
                                      vrs);
      if (rsf)
        smartlist_add(chunks, rsf);
  
      for (h = vrs->microdesc; h; h = h->next) {
        smartlist_add_strdup(chunks, h->microdesc_hash_line);
      }
    } SMARTLIST_FOREACH_END(vrs);
  
    smartlist_add_strdup(chunks, "directory-footer\n");
  
    /* The digest includes everything up through the space after
     * directory-signature.  (Yuck.) */
    crypto_digest_smartlist(digest, DIGEST_LEN, chunks,
                            "directory-signature ", DIGEST_SHA1);
  
    {
      char signing_key_fingerprint[FINGERPRINT_LEN+1];
      if (crypto_pk_get_fingerprint(private_signing_key,
                                    signing_key_fingerprint, 0)<0) {
        log_warn(LD_BUG, "Unable to get fingerprint for signing key");
        goto err;
      }
  
      smartlist_add_asprintf(chunks, "directory-signature %s %s\n", fingerprint,
                             signing_key_fingerprint);
    }
  
    {
      char *sig = router_get_dirobj_signature(digest, DIGEST_LEN,
                                              private_signing_key);
      if (!sig) {
        log_warn(LD_BUG, "Unable to sign networkstatus vote.");
        goto err;
      }
      smartlist_add(chunks, sig);
    }
  
    status = smartlist_join_strings(chunks, "", 0, NULL);
  
    {
      networkstatus_t *v;
      if (!(v = networkstatus_parse_vote_from_string(status, strlen(status),
                                                     NULL,
                                                     v3_ns->type))) {
        log_err(LD_BUG,"Generated a networkstatus %s we couldn't parse: "
                "<<%s>>",
                v3_ns->type == NS_TYPE_VOTE ? "vote" : "opinion", status);
        goto err;
      }
      networkstatus_vote_free(v);
    }
  
    goto done;
  
   err:
    tor_free(status);
   done:
    tor_free(client_versions_line);
    tor_free(server_versions_line);
    tor_free(protocols_lines);
    tor_free(packages);
  
    SMARTLIST_FOREACH(chunks, char *, cp, tor_free(cp));
    smartlist_free(chunks);
    return status;
  }
  
  /** Set *<b>timing_out</b> to the intervals at which we would like to vote.
   * Note that these aren't the intervals we'll use to vote; they're the ones
   * that we'll vote to use. */
  static void
  dirvote_get_preferred_voting_intervals(vote_timing_t *timing_out)
  {
    const or_options_t *options = get_options();
  
    tor_assert(timing_out);
  
    timing_out->vote_interval = options->V3AuthVotingInterval;
    timing_out->n_intervals_valid = options->V3AuthNIntervalsValid;
    timing_out->vote_delay = options->V3AuthVoteDelay;
    timing_out->dist_delay = options->V3AuthDistDelay;
  }
  
  /* =====
   * Consensus generation
   * ===== */
  
  /** If <b>vrs</b> has a hash made for the consensus method <b>method</b> with
   * the digest algorithm <b>alg</b>, decode it and copy it into
   * <b>digest256_out</b> and return 0.  Otherwise return -1. */
  static int
  vote_routerstatus_find_microdesc_hash(char *digest256_out,
                                        const vote_routerstatus_t *vrs,
                                        int method,
                                        digest_algorithm_t alg)
  {
    /* XXXX only returns the sha256 method. */
    const vote_microdesc_hash_t *h;
    char mstr[64];
    size_t mlen;
    char dstr[64];
  
    tor_snprintf(mstr, sizeof(mstr), "%d", method);
    mlen = strlen(mstr);
    tor_snprintf(dstr, sizeof(dstr), " %s=",
                 crypto_digest_algorithm_get_name(alg));
  
    for (h = vrs->microdesc; h; h = h->next) {
      const char *cp = h->microdesc_hash_line;
      size_t num_len;
      /* cp looks like \d+(,\d+)* (digesttype=val )+ .  Let's hunt for mstr in
       * the first part. */
      while (1) {
        num_len = strspn(cp, "1234567890");
        if (num_len == mlen && fast_memeq(mstr, cp, mlen)) {
          /* This is the line. */
          char buf[BASE64_DIGEST256_LEN+1];
          /* XXXX ignores extraneous stuff if the digest is too long.  This
           * seems harmless enough, right? */
          cp = strstr(cp, dstr);
          if (!cp)
            return -1;
          cp += strlen(dstr);
          strlcpy(buf, cp, sizeof(buf));
          return digest256_from_base64(digest256_out, buf);
        }
        if (num_len == 0 || cp[num_len] != ',')
          break;
        cp += num_len + 1;
      }
    }
    return -1;
  }
  
  /** Given a vote <b>vote</b> (not a consensus!), return its associated
   * networkstatus_voter_info_t. */
  static networkstatus_voter_info_t *
  get_voter(const networkstatus_t *vote)
  {
    tor_assert(vote);
    tor_assert(vote->type == NS_TYPE_VOTE);
    tor_assert(vote->voters);
    tor_assert(smartlist_len(vote->voters) == 1);
    return smartlist_get(vote->voters, 0);
  }
  
  /** Temporary structure used in constructing a list of dir-source entries
   * for a consensus.  One of these is generated for every vote, and one more
   * for every legacy key in each vote. */
  typedef struct dir_src_ent_t {
    networkstatus_t *v;
    const char *digest;
    int is_legacy;
  } dir_src_ent_t;
  
  /** Helper for sorting networkstatus_t votes (not consensuses) by the
   * hash of their voters' identity digests. */
  static int
  compare_votes_by_authority_id_(const void **_a, const void **_b)
  {
    const networkstatus_t *a = *_a, *b = *_b;
    return fast_memcmp(get_voter(a)->identity_digest,
                  get_voter(b)->identity_digest, DIGEST_LEN);
  }
  
  /** Helper: Compare the dir_src_ent_ts in *<b>_a</b> and *<b>_b</b> by
   * their identity digests, and return -1, 0, or 1 depending on their
   * ordering */
  static int
  compare_dir_src_ents_by_authority_id_(const void **_a, const void **_b)
  {
    const dir_src_ent_t *a = *_a, *b = *_b;
    const networkstatus_voter_info_t *a_v = get_voter(a->v),
      *b_v = get_voter(b->v);
    const char *a_id, *b_id;
    a_id = a->is_legacy ? a_v->legacy_id_digest : a_v->identity_digest;
    b_id = b->is_legacy ? b_v->legacy_id_digest : b_v->identity_digest;
  
    return fast_memcmp(a_id, b_id, DIGEST_LEN);
  }
  
  /** Given a sorted list of strings <b>in</b>, add every member to <b>out</b>
   * that occurs more than <b>min</b> times. */
  static void
  get_frequent_members(smartlist_t *out, smartlist_t *in, int min)
  {
    char *cur = NULL;
    int count = 0;
    SMARTLIST_FOREACH_BEGIN(in, char *, cp) {
      if (cur && !strcmp(cp, cur)) {
        ++count;
      } else {
        if (count > min)
          smartlist_add(out, cur);
        cur = cp;
        count = 1;
      }
    } SMARTLIST_FOREACH_END(cp);
    if (count > min)
      smartlist_add(out, cur);
  }
  
  /** Given a sorted list of strings <b>lst</b>, return the member that appears
   * most.  Break ties in favor of later-occurring members. */
  #define get_most_frequent_member(lst)           \
    smartlist_get_most_frequent_string(lst)
  
  /** Return 0 if and only if <b>a</b> and <b>b</b> are routerstatuses
   * that come from the same routerinfo, with the same derived elements.
   */
  static int
  compare_vote_rs(const vote_routerstatus_t *a, const vote_routerstatus_t *b)
  {
    int r;
    tor_assert(a);
    tor_assert(b);
  
    if ((r = fast_memcmp(a->status.identity_digest, b->status.identity_digest,
                    DIGEST_LEN)))
      return r;
    if ((r = fast_memcmp(a->status.descriptor_digest,
                         b->status.descriptor_digest,
                         DIGEST_LEN)))
      return r;
    /* If we actually reached this point, then the identities and
     * the descriptor digests matched, so somebody is making SHA1 collisions.
     */
  #define CMP_FIELD(utype, itype, field) do {                             \
      utype aval = (utype) (itype) a->status.field;                       \
      utype bval = (utype) (itype) b->status.field;                       \
      utype u = bval - aval;                                              \
      itype r2 = (itype) u;                                               \
      if (r2 < 0) {                                                       \
        return -1;                                                        \
      } else if (r2 > 0) {                                                \
        return 1;                                                         \
      }                                                                   \
    } while (0)
  
    CMP_FIELD(uint64_t, int64_t, published_on);
  
    if ((r = strcmp(b->status.nickname, a->status.nickname)))
      return r;
  
    CMP_FIELD(unsigned, int, addr);
    CMP_FIELD(unsigned, int, or_port);
    CMP_FIELD(unsigned, int, dir_port);
  
    return 0;
  }
  
  /** Helper for sorting routerlists based on compare_vote_rs. */
  static int
  compare_vote_rs_(const void **_a, const void **_b)
  {
    const vote_routerstatus_t *a = *_a, *b = *_b;
    return compare_vote_rs(a,b);
  }
  
  /** Helper for sorting OR ports. */
  static int
  compare_orports_(const void **_a, const void **_b)
  {
    const tor_addr_port_t *a = *_a, *b = *_b;
    int r;
  
    if ((r = tor_addr_compare(&a->addr, &b->addr, CMP_EXACT)))
      return r;
    if ((r = (((int) b->port) - ((int) a->port))))
      return r;
  
    return 0;
  }
  
  /** Given a list of vote_routerstatus_t, all for the same router identity,
   * return whichever is most frequent, breaking ties in favor of more
   * recently published vote_routerstatus_t and in case of ties there,
   * in favor of smaller descriptor digest.
   */
  static vote_routerstatus_t *
  compute_routerstatus_consensus(smartlist_t *votes, int consensus_method,
                                 char *microdesc_digest256_out,
                                 tor_addr_port_t *best_alt_orport_out)
  {
    vote_routerstatus_t *most = NULL, *cur = NULL;
    int most_n = 0, cur_n = 0;
    time_t most_published = 0;
  
    /* compare_vote_rs_() sorts the items by identity digest (all the same),
     * then by SD digest.  That way, if we have a tie that the published_on
     * date cannot break, we use the descriptor with the smaller digest.
     */
    smartlist_sort(votes, compare_vote_rs_);
    SMARTLIST_FOREACH_BEGIN(votes, vote_routerstatus_t *, rs) {
      if (cur && !compare_vote_rs(cur, rs)) {
        ++cur_n;
      } else {
        if (cur && (cur_n > most_n ||
                    (cur_n == most_n &&
                     cur->status.published_on > most_published))) {
          most = cur;
          most_n = cur_n;
          most_published = cur->status.published_on;
        }
        cur_n = 1;
        cur = rs;
      }
    } SMARTLIST_FOREACH_END(rs);
  
    if (cur_n > most_n ||
        (cur && cur_n == most_n && cur->status.published_on > most_published)) {
      most = cur;
      // most_n = cur_n; // unused after this point.
      // most_published = cur->status.published_on; // unused after this point.
    }
  
    tor_assert(most);
  
    /* Vote on potential alternative (sets of) OR port(s) in the winning
     * routerstatuses.
     *
     * XXX prop186 There's at most one alternative OR port (_the_ IPv6
     * port) for now. */
    if (best_alt_orport_out) {
      smartlist_t *alt_orports = smartlist_new();
      const tor_addr_port_t *most_alt_orport = NULL;
  
      SMARTLIST_FOREACH_BEGIN(votes, vote_routerstatus_t *, rs) {
        tor_assert(rs);
        if (compare_vote_rs(most, rs) == 0 &&
            !tor_addr_is_null(&rs->status.ipv6_addr)
            && rs->status.ipv6_orport) {
          smartlist_add(alt_orports, tor_addr_port_new(&rs->status.ipv6_addr,
                                                       rs->status.ipv6_orport));
        }
      } SMARTLIST_FOREACH_END(rs);
  
      smartlist_sort(alt_orports, compare_orports_);
      most_alt_orport = smartlist_get_most_frequent(alt_orports,
                                                    compare_orports_);
      if (most_alt_orport) {
        memcpy(best_alt_orport_out, most_alt_orport, sizeof(tor_addr_port_t));
        log_debug(LD_DIR, "\"a\" line winner for %s is %s",
                  most->status.nickname,
                  fmt_addrport(&most_alt_orport->addr, most_alt_orport->port));
      }
  
      SMARTLIST_FOREACH(alt_orports, tor_addr_port_t *, ap, tor_free(ap));
      smartlist_free(alt_orports);
    }
  
    if (microdesc_digest256_out) {
      smartlist_t *digests = smartlist_new();
      const uint8_t *best_microdesc_digest;
      SMARTLIST_FOREACH_BEGIN(votes, vote_routerstatus_t *, rs) {
          char d[DIGEST256_LEN];
          if (compare_vote_rs(rs, most))
            continue;
          if (!vote_routerstatus_find_microdesc_hash(d, rs, consensus_method,
                                                     DIGEST_SHA256))
            smartlist_add(digests, tor_memdup(d, sizeof(d)));
      } SMARTLIST_FOREACH_END(rs);
      smartlist_sort_digests256(digests);
      best_microdesc_digest = smartlist_get_most_frequent_digest256(digests);
      if (best_microdesc_digest)
        memcpy(microdesc_digest256_out, best_microdesc_digest, DIGEST256_LEN);
      SMARTLIST_FOREACH(digests, char *, cp, tor_free(cp));
      smartlist_free(digests);
    }
  
    return most;
  }
  
  /** Sorting helper: compare two strings based on their values as base-ten
   * positive integers. (Non-integers are treated as prior to all integers, and
   * compared lexically.) */
  static int
  cmp_int_strings_(const void **_a, const void **_b)
  {
    const char *a = *_a, *b = *_b;
    int ai = (int)tor_parse_long(a, 10, 1, INT_MAX, NULL, NULL);
    int bi = (int)tor_parse_long(b, 10, 1, INT_MAX, NULL, NULL);
    if (ai<bi) {
      return -1;
    } else if (ai==bi) {
      if (ai == 0) /* Parsing failed. */
        return strcmp(a, b);
      return 0;
    } else {
      return 1;
    }
  }
  
  /** Given a list of networkstatus_t votes, determine and return the number of
   * the highest consensus method that is supported by 2/3 of the voters. */
  static int
  compute_consensus_method(smartlist_t *votes)
  {
    smartlist_t *all_methods = smartlist_new();
    smartlist_t *acceptable_methods = smartlist_new();
    smartlist_t *tmp = smartlist_new();
    int min = (smartlist_len(votes) * 2) / 3;
    int n_ok;
    int result;
    SMARTLIST_FOREACH(votes, networkstatus_t *, vote,
    {
      tor_assert(vote->supported_methods);
      smartlist_add_all(tmp, vote->supported_methods);
      smartlist_sort(tmp, cmp_int_strings_);
      smartlist_uniq(tmp, cmp_int_strings_, NULL);
      smartlist_add_all(all_methods, tmp);
      smartlist_clear(tmp);
    });
  
    smartlist_sort(all_methods, cmp_int_strings_);
    get_frequent_members(acceptable_methods, all_methods, min);
    n_ok = smartlist_len(acceptable_methods);
    if (n_ok) {
      const char *best = smartlist_get(acceptable_methods, n_ok-1);
      result = (int)tor_parse_long(best, 10, 1, INT_MAX, NULL, NULL);
    } else {
      result = 1;
    }
    smartlist_free(tmp);
    smartlist_free(all_methods);
    smartlist_free(acceptable_methods);
    return result;
  }
  
  /** Return true iff <b>method</b> is a consensus method that we support. */
  static int
  consensus_method_is_supported(int method)
  {
    return (method >= MIN_SUPPORTED_CONSENSUS_METHOD) &&
      (method <= MAX_SUPPORTED_CONSENSUS_METHOD);
  }
  
  /** Return a newly allocated string holding the numbers between low and high
   * (inclusive) that are supported consensus methods. */
  STATIC char *
  make_consensus_method_list(int low, int high, const char *separator)
  {
    char *list;
  
    int i;
    smartlist_t *lst;
    lst = smartlist_new();
    for (i = low; i <= high; ++i) {
      if (!consensus_method_is_supported(i))
        continue;
      smartlist_add_asprintf(lst, "%d", i);
    }
    list = smartlist_join_strings(lst, separator, 0, NULL);
    tor_assert(list);
    SMARTLIST_FOREACH(lst, char *, cp, tor_free(cp));
    smartlist_free(lst);
    return list;
  }
  
  /** Helper: given <b>lst</b>, a list of version strings such that every
   * version appears once for every versioning voter who recommends it, return a
   * newly allocated string holding the resulting client-versions or
   * server-versions list. May change contents of <b>lst</b> */
  static char *
  compute_consensus_versions_list(smartlist_t *lst, int n_versioning)
  {
    int min = n_versioning / 2;
    smartlist_t *good = smartlist_new();
    char *result;
    SMARTLIST_FOREACH_BEGIN(lst, const char *, v) {
      if (strchr(v, ' ')) {
        log_warn(LD_DIR, "At least one authority has voted for a version %s "
                 "that contains a space. This probably wasn't intentional, and "
                 "is likely to cause trouble. Please tell them to stop it.",
                 escaped(v));
      }
    } SMARTLIST_FOREACH_END(v);
    sort_version_list(lst, 0);
    get_frequent_members(good, lst, min);
    result = smartlist_join_strings(good, ",", 0, NULL);
    smartlist_free(good);
    return result;
  }
  
  /** Given a list of K=V values, return the int32_t value corresponding to
   * KEYWORD=, or default_val if no such value exists, or if the value is
   * corrupt.
   */
  STATIC int32_t
  dirvote_get_intermediate_param_value(const smartlist_t *param_list,
                                       const char *keyword,
                                       int32_t default_val)
  {
    unsigned int n_found = 0;
    int32_t value = default_val;
  
    SMARTLIST_FOREACH_BEGIN(param_list, const char *, k_v_pair) {
      if (!strcmpstart(k_v_pair, keyword) && k_v_pair[strlen(keyword)] == '=') {
        const char *integer_str = &k_v_pair[strlen(keyword)+1];
        int ok;
        value = (int32_t)
          tor_parse_long(integer_str, 10, INT32_MIN, INT32_MAX, &ok, NULL);
        if (BUG(! ok))
          return default_val;
        ++n_found;
      }
    } SMARTLIST_FOREACH_END(k_v_pair);
  
    if (n_found == 1) {
      return value;
    } else {
      tor_assert_nonfatal(n_found == 0);
      return default_val;
    }
  }
  
  /** Minimum number of directory authorities voting for a parameter to
   * include it in the consensus, if consensus method 12 or later is to be
   * used. See proposal 178 for details. */
  #define MIN_VOTES_FOR_PARAM 3
  
  /** Helper: given a list of valid networkstatus_t, return a new smartlist
   * containing the contents of the consensus network parameter set.
   */
  STATIC smartlist_t *
  dirvote_compute_params(smartlist_t *votes, int method, int total_authorities)
  {
    int i;
    int32_t *vals;
  
    int cur_param_len;
    const char *cur_param;
    const char *eq;
  
    const int n_votes = smartlist_len(votes);
    smartlist_t *output;
    smartlist_t *param_list = smartlist_new();
    (void) method;
  
    /* We require that the parameter lists in the votes are well-formed: that
       is, that their keywords are unique and sorted, and that their values are
       between INT32_MIN and INT32_MAX inclusive.  This should be guaranteed by
       the parsing code. */
  
    vals = tor_calloc(n_votes, sizeof(int));
  
    SMARTLIST_FOREACH_BEGIN(votes, networkstatus_t *, v) {
      if (!v->net_params)
        continue;
      smartlist_add_all(param_list, v->net_params);
    } SMARTLIST_FOREACH_END(v);
  
    if (smartlist_len(param_list) == 0) {
      tor_free(vals);
      return param_list;
    }
  
    smartlist_sort_strings(param_list);
    i = 0;
    cur_param = smartlist_get(param_list, 0);
    eq = strchr(cur_param, '=');
    tor_assert(eq);
    cur_param_len = (int)(eq+1 - cur_param);
  
    output = smartlist_new();
  
    SMARTLIST_FOREACH_BEGIN(param_list, const char *, param) {
      /* resolve spurious clang shallow analysis null pointer errors */
      tor_assert(param);
  
      const char *next_param;
      int ok=0;
      eq = strchr(param, '=');
      tor_assert(i<n_votes); /* Make sure we prevented vote-stuffing. */
      vals[i++] = (int32_t)
        tor_parse_long(eq+1, 10, INT32_MIN, INT32_MAX, &ok, NULL);
      tor_assert(ok); /* Already checked these when parsing. */
  
      if (param_sl_idx+1 == smartlist_len(param_list))
        next_param = NULL;
      else
        next_param = smartlist_get(param_list, param_sl_idx+1);
  
      if (!next_param || strncmp(next_param, param, cur_param_len)) {
        /* We've reached the end of a series. */
        /* Make sure enough authorities voted on this param, unless the
         * the consensus method we use is too old for that. */
        if (i > total_authorities/2 ||
            i >= MIN_VOTES_FOR_PARAM) {
          int32_t median = median_int32(vals, i);
          char *out_string = tor_malloc(64+cur_param_len);
          memcpy(out_string, param, cur_param_len);
          tor_snprintf(out_string+cur_param_len,64, "%ld", (long)median);
          smartlist_add(output, out_string);
        }
  
        i = 0;
        if (next_param) {
          eq = strchr(next_param, '=');
          cur_param_len = (int)(eq+1 - next_param);
        }
      }
    } SMARTLIST_FOREACH_END(param);
  
    smartlist_free(param_list);
    tor_free(vals);
    return output;
  }
  
  #define RANGE_CHECK(a,b,c,d,e,f,g,mx) \
         ((a) >= 0 && (a) <= (mx) && (b) >= 0 && (b) <= (mx) && \
          (c) >= 0 && (c) <= (mx) && (d) >= 0 && (d) <= (mx) && \
          (e) >= 0 && (e) <= (mx) && (f) >= 0 && (f) <= (mx) && \
          (g) >= 0 && (g) <= (mx))
  
  #define CHECK_EQ(a, b, margin) \
       ((a)-(b) >= 0 ? (a)-(b) <= (margin) : (b)-(a) <= (margin))
  
  typedef enum {
   BW_WEIGHTS_NO_ERROR = 0,
   BW_WEIGHTS_RANGE_ERROR = 1,
   BW_WEIGHTS_SUMG_ERROR = 2,
   BW_WEIGHTS_SUME_ERROR = 3,
   BW_WEIGHTS_SUMD_ERROR = 4,
   BW_WEIGHTS_BALANCE_MID_ERROR = 5,
   BW_WEIGHTS_BALANCE_EG_ERROR = 6
  } bw_weights_error_t;
  
  /**
   * Verify that any weightings satisfy the balanced formulas.
   */
  static bw_weights_error_t
  networkstatus_check_weights(int64_t Wgg, int64_t Wgd, int64_t Wmg,
                              int64_t Wme, int64_t Wmd, int64_t Wee,
                              int64_t Wed, int64_t scale, int64_t G,
                              int64_t M, int64_t E, int64_t D, int64_t T,
                              int64_t margin, int do_balance) {
    bw_weights_error_t berr = BW_WEIGHTS_NO_ERROR;
  
    // Wed + Wmd + Wgd == 1
    if (!CHECK_EQ(Wed + Wmd + Wgd, scale, margin)) {
      berr = BW_WEIGHTS_SUMD_ERROR;
      goto out;
    }
  
    // Wmg + Wgg == 1
    if (!CHECK_EQ(Wmg + Wgg, scale, margin)) {
      berr = BW_WEIGHTS_SUMG_ERROR;
      goto out;
    }
  
    // Wme + Wee == 1
    if (!CHECK_EQ(Wme + Wee, scale, margin)) {
      berr = BW_WEIGHTS_SUME_ERROR;
      goto out;
    }
  
    // Verify weights within range 0->1
    if (!RANGE_CHECK(Wgg, Wgd, Wmg, Wme, Wmd, Wed, Wee, scale)) {
      berr = BW_WEIGHTS_RANGE_ERROR;
      goto out;
    }
  
    if (do_balance) {
      // Wgg*G + Wgd*D == Wee*E + Wed*D, already scaled
      if (!CHECK_EQ(Wgg*G + Wgd*D, Wee*E + Wed*D, (margin*T)/3)) {
        berr = BW_WEIGHTS_BALANCE_EG_ERROR;
        goto out;
      }
  
      // Wgg*G + Wgd*D == M*scale + Wmd*D + Wme*E + Wmg*G, already scaled
      if (!CHECK_EQ(Wgg*G + Wgd*D, M*scale + Wmd*D + Wme*E + Wmg*G,
                  (margin*T)/3)) {
        berr = BW_WEIGHTS_BALANCE_MID_ERROR;
        goto out;
      }
    }
  
   out:
    if (berr) {
      log_info(LD_DIR,
               "Bw weight mismatch %d. G=%"PRId64" M=%"PRId64
               " E=%"PRId64" D=%"PRId64" T=%"PRId64
               " Wmd=%d Wme=%d Wmg=%d Wed=%d Wee=%d"
               " Wgd=%d Wgg=%d Wme=%d Wmg=%d",
               berr,
               (G), (M), (E),
               (D), (T),
               (int)Wmd, (int)Wme, (int)Wmg, (int)Wed, (int)Wee,
               (int)Wgd, (int)Wgg, (int)Wme, (int)Wmg);
    }
  
    return berr;
  }
  
  /**
   * This function computes the bandwidth weights for consensus method 10.
   *
   * It returns true if weights could be computed, false otherwise.
   */
  int
  networkstatus_compute_bw_weights_v10(smartlist_t *chunks, int64_t G,
                                       int64_t M, int64_t E, int64_t D,
                                       int64_t T, int64_t weight_scale)
  {
    bw_weights_error_t berr = 0;
    int64_t Wgg = -1, Wgd = -1;
    int64_t Wmg = -1, Wme = -1, Wmd = -1;
    int64_t Wed = -1, Wee = -1;
    const char *casename;
  
    if (G <= 0 || M <= 0 || E <= 0 || D <= 0) {
      log_warn(LD_DIR, "Consensus with empty bandwidth: "
                       "G=%"PRId64" M=%"PRId64" E=%"PRId64
                       " D=%"PRId64" T=%"PRId64,
               (G), (M), (E),
               (D), (T));
      return 0;
    }
  
    /*
     * Computed from cases in 3.8.3 of dir-spec.txt
     *
     * 1. Neither are scarce
     * 2. Both Guard and Exit are scarce
     *    a. R+D <= S
     *    b. R+D > S
     * 3. One of Guard or Exit is scarce
     *    a. S+D < T/3
     *    b. S+D >= T/3
     */
    if (3*E >= T && 3*G >= T) { // E >= T/3 && G >= T/3
      /* Case 1: Neither are scarce.  */
      casename = "Case 1 (Wgd=Wmd=Wed)";
      Wgd = weight_scale/3;
      Wed = weight_scale/3;
      Wmd = weight_scale/3;
      Wee = (weight_scale*(E+G+M))/(3*E);
      Wme = weight_scale - Wee;
      Wmg = (weight_scale*(2*G-E-M))/(3*G);
      Wgg = weight_scale - Wmg;
  
      berr = networkstatus_check_weights(Wgg, Wgd, Wmg, Wme, Wmd, Wee, Wed,
                                         weight_scale, G, M, E, D, T, 10, 1);
  
      if (berr) {
        log_warn(LD_DIR,
               "Bw Weights error %d for %s v10. G=%"PRId64" M=%"PRId64
               " E=%"PRId64" D=%"PRId64" T=%"PRId64
               " Wmd=%d Wme=%d Wmg=%d Wed=%d Wee=%d"
               " Wgd=%d Wgg=%d Wme=%d Wmg=%d weight_scale=%d",
               berr, casename,
               (G), (M), (E),
               (D), (T),
               (int)Wmd, (int)Wme, (int)Wmg, (int)Wed, (int)Wee,
               (int)Wgd, (int)Wgg, (int)Wme, (int)Wmg, (int)weight_scale);
        return 0;
      }
    } else if (3*E < T && 3*G < T) { // E < T/3 && G < T/3
      int64_t R = MIN(E, G);
      int64_t S = MAX(E, G);
      /*
       * Case 2: Both Guards and Exits are scarce
       * Balance D between E and G, depending upon
       * D capacity and scarcity.
       */
      if (R+D < S) { // Subcase a
        Wgg = weight_scale;
        Wee = weight_scale;
        Wmg = 0;
        Wme = 0;
        Wmd = 0;
        if (E < G) {
          casename = "Case 2a (E scarce)";
          Wed = weight_scale;
          Wgd = 0;
        } else { /* E >= G */
          casename = "Case 2a (G scarce)";
          Wed = 0;
          Wgd = weight_scale;
        }
      } else { // Subcase b: R+D >= S
        casename = "Case 2b1 (Wgg=weight_scale, Wmd=Wgd)";
        Wee = (weight_scale*(E - G + M))/E;
        Wed = (weight_scale*(D - 2*E + 4*G - 2*M))/(3*D);
        Wme = (weight_scale*(G-M))/E;
        Wmg = 0;
        Wgg = weight_scale;
        Wmd = (weight_scale - Wed)/2;
        Wgd = (weight_scale - Wed)/2;
  
        berr = networkstatus_check_weights(Wgg, Wgd, Wmg, Wme, Wmd, Wee, Wed,
                                         weight_scale, G, M, E, D, T, 10, 1);
  
        if (berr) {
          casename = "Case 2b2 (Wgg=weight_scale, Wee=weight_scale)";
          Wgg = weight_scale;
          Wee = weight_scale;
          Wed = (weight_scale*(D - 2*E + G + M))/(3*D);
          Wmd = (weight_scale*(D - 2*M + G + E))/(3*D);
          Wme = 0;
          Wmg = 0;
  
          if (Wmd < 0) { // Can happen if M > T/3
            casename = "Case 2b3 (Wmd=0)";
            Wmd = 0;
            log_warn(LD_DIR,
                     "Too much Middle bandwidth on the network to calculate "
                     "balanced bandwidth-weights. Consider increasing the "
                     "number of Guard nodes by lowering the requirements.");
          }
          Wgd = weight_scale - Wed - Wmd;
          berr = networkstatus_check_weights(Wgg, Wgd, Wmg, Wme, Wmd, Wee,
                    Wed, weight_scale, G, M, E, D, T, 10, 1);
        }
        if (berr != BW_WEIGHTS_NO_ERROR &&
                berr != BW_WEIGHTS_BALANCE_MID_ERROR) {
          log_warn(LD_DIR,
               "Bw Weights error %d for %s v10. G=%"PRId64" M=%"PRId64
               " E=%"PRId64" D=%"PRId64" T=%"PRId64
               " Wmd=%d Wme=%d Wmg=%d Wed=%d Wee=%d"
               " Wgd=%d Wgg=%d Wme=%d Wmg=%d weight_scale=%d",
               berr, casename,
               (G), (M), (E),
               (D), (T),
               (int)Wmd, (int)Wme, (int)Wmg, (int)Wed, (int)Wee,
               (int)Wgd, (int)Wgg, (int)Wme, (int)Wmg, (int)weight_scale);
          return 0;
        }
      }
    } else { // if (E < T/3 || G < T/3) {
      int64_t S = MIN(E, G);
      // Case 3: Exactly one of Guard or Exit is scarce
      if (!(3*E < T || 3*G < T) || !(3*G >= T || 3*E >= T)) {
        log_warn(LD_BUG,
             "Bw-Weights Case 3 v10 but with G=%"PRId64" M="
             "%"PRId64" E=%"PRId64" D=%"PRId64" T=%"PRId64,
                 (G), (M), (E),
                 (D), (T));
      }
  
      if (3*(S+D) < T) { // Subcase a: S+D < T/3
        if (G < E) {
          casename = "Case 3a (G scarce)";
          Wgg = Wgd = weight_scale;
          Wmd = Wed = Wmg = 0;
          // Minor subcase, if E is more scarce than M,
          // keep its bandwidth in place.
          if (E < M) Wme = 0;
          else Wme = (weight_scale*(E-M))/(2*E);
          Wee = weight_scale-Wme;
        } else { // G >= E
          casename = "Case 3a (E scarce)";
          Wee = Wed = weight_scale;
          Wmd = Wgd = Wme = 0;
          // Minor subcase, if G is more scarce than M,
          // keep its bandwidth in place.
          if (G < M) Wmg = 0;
          else Wmg = (weight_scale*(G-M))/(2*G);
          Wgg = weight_scale-Wmg;
        }
      } else { // Subcase b: S+D >= T/3
        // D != 0 because S+D >= T/3
        if (G < E) {
          casename = "Case 3bg (G scarce, Wgg=weight_scale, Wmd == Wed)";
          Wgg = weight_scale;
          Wgd = (weight_scale*(D - 2*G + E + M))/(3*D);
          Wmg = 0;
          Wee = (weight_scale*(E+M))/(2*E);
          Wme = weight_scale - Wee;
          Wmd = (weight_scale - Wgd)/2;
          Wed = (weight_scale - Wgd)/2;
  
          berr = networkstatus_check_weights(Wgg, Wgd, Wmg, Wme, Wmd, Wee,
                      Wed, weight_scale, G, M, E, D, T, 10, 1);
        } else { // G >= E
          casename = "Case 3be (E scarce, Wee=weight_scale, Wmd == Wgd)";
          Wee = weight_scale;
          Wed = (weight_scale*(D - 2*E + G + M))/(3*D);
          Wme = 0;
          Wgg = (weight_scale*(G+M))/(2*G);
          Wmg = weight_scale - Wgg;
          Wmd = (weight_scale - Wed)/2;
          Wgd = (weight_scale - Wed)/2;
  
          berr = networkstatus_check_weights(Wgg, Wgd, Wmg, Wme, Wmd, Wee,
                        Wed, weight_scale, G, M, E, D, T, 10, 1);
        }
        if (berr) {
          log_warn(LD_DIR,
               "Bw Weights error %d for %s v10. G=%"PRId64" M=%"PRId64
               " E=%"PRId64" D=%"PRId64" T=%"PRId64
               " Wmd=%d Wme=%d Wmg=%d Wed=%d Wee=%d"
               " Wgd=%d Wgg=%d Wme=%d Wmg=%d weight_scale=%d",
               berr, casename,
               (G), (M), (E),
               (D), (T),
               (int)Wmd, (int)Wme, (int)Wmg, (int)Wed, (int)Wee,
               (int)Wgd, (int)Wgg, (int)Wme, (int)Wmg, (int)weight_scale);
          return 0;
        }
      }
    }
  
    /* We cast down the weights to 32 bit ints on the assumption that
     * weight_scale is ~= 10000. We need to ensure a rogue authority
     * doesn't break this assumption to rig our weights */
    tor_assert(0 < weight_scale && weight_scale <= INT32_MAX);
  
    /*
     * Provide Wgm=Wgg, Wmm=weight_scale, Wem=Wee, Weg=Wed. May later determine
     * that middle nodes need different bandwidth weights for dirport traffic,
     * or that weird exit policies need special weight, or that bridges
     * need special weight.
     *
     * NOTE: This list is sorted.
     */
    smartlist_add_asprintf(chunks,
       "bandwidth-weights Wbd=%d Wbe=%d Wbg=%d Wbm=%d "
       "Wdb=%d "
       "Web=%d Wed=%d Wee=%d Weg=%d Wem=%d "
       "Wgb=%d Wgd=%d Wgg=%d Wgm=%d "
       "Wmb=%d Wmd=%d Wme=%d Wmg=%d Wmm=%d\n",
       (int)Wmd, (int)Wme, (int)Wmg, (int)weight_scale,
       (int)weight_scale,
       (int)weight_scale, (int)Wed, (int)Wee, (int)Wed, (int)Wee,
       (int)weight_scale, (int)Wgd, (int)Wgg, (int)Wgg,
       (int)weight_scale, (int)Wmd, (int)Wme, (int)Wmg, (int)weight_scale);
  
    log_notice(LD_CIRC, "Computed bandwidth weights for %s with v10: "
               "G=%"PRId64" M=%"PRId64" E=%"PRId64" D=%"PRId64
               " T=%"PRId64,
               casename,
               (G), (M), (E),
               (D), (T));
    return 1;
  }
  
  /** Update total bandwidth weights (G/M/E/D/T) with the bandwidth of
   *  the router in <b>rs</b>. */
  static void
  update_total_bandwidth_weights(const routerstatus_t *rs,
                                 int is_exit, int is_guard,
                                 int64_t *G, int64_t *M, int64_t *E, int64_t *D,
                                 int64_t *T)
  {
    int default_bandwidth = rs->bandwidth_kb;
    int guardfraction_bandwidth = 0;
  
    if (!rs->has_bandwidth) {
      log_info(LD_BUG, "Missing consensus bandwidth for router %s",
               rs->nickname);
      return;
    }
  
    /* If this routerstatus represents a guard that we have
     * guardfraction information on, use it to calculate its actual
     * bandwidth. From proposal236:
     *
     *    Similarly, when calculating the bandwidth-weights line as in
     *    section 3.8.3 of dir-spec.txt, directory authorities should treat N
     *    as if fraction F of its bandwidth has the guard flag and (1-F) does
     *    not.  So when computing the totals G,M,E,D, each relay N with guard
     *    visibility fraction F and bandwidth B should be added as follows:
     *
     *    G' = G + F*B, if N does not have the exit flag
     *    M' = M + (1-F)*B, if N does not have the exit flag
     *
     *    or
     *
     *    D' = D + F*B, if N has the exit flag
     *    E' = E + (1-F)*B, if N has the exit flag
     *
     * In this block of code, we prepare the bandwidth values by setting
     * the default_bandwidth to F*B and guardfraction_bandwidth to (1-F)*B.
     */
    if (rs->has_guardfraction) {
      guardfraction_bandwidth_t guardfraction_bw;
  
      tor_assert(is_guard);
  
      guard_get_guardfraction_bandwidth(&guardfraction_bw,
                                        rs->bandwidth_kb,
                                        rs->guardfraction_percentage);
  
      default_bandwidth = guardfraction_bw.guard_bw;
      guardfraction_bandwidth = guardfraction_bw.non_guard_bw;
    }
  
    /* Now calculate the total bandwidth weights with or without
     * guardfraction. Depending on the flags of the relay, add its
     * bandwidth to the appropriate weight pool. If it's a guard and
     * guardfraction is enabled, add its bandwidth to both pools as
     * indicated by the previous comment.
     */
    *T += default_bandwidth;
    if (is_exit && is_guard) {
  
      *D += default_bandwidth;
      if (rs->has_guardfraction) {
        *E += guardfraction_bandwidth;
      }
  
    } else if (is_exit) {
  
      *E += default_bandwidth;
  
    } else if (is_guard) {
  
      *G += default_bandwidth;
      if (rs->has_guardfraction) {
        *M += guardfraction_bandwidth;
      }
  
    } else {
  
      *M += default_bandwidth;
    }
  }
  
  /** Considering the different recommended/required protocols sets as a
   * 4-element array, return the element from <b>vote</b> for that protocol
   * set.
   */
  static const char *
  get_nth_protocol_set_vote(int n, const networkstatus_t *vote)
  {
    switch (n) {
      case 0: return vote->recommended_client_protocols;
      case 1: return vote->recommended_relay_protocols;
      case 2: return vote->required_client_protocols;
      case 3: return vote->required_relay_protocols;
      default:
        tor_assert_unreached();
        return NULL;
    }
  }
  
  /** Considering the different recommended/required protocols sets as a
   * 4-element array, return a newly allocated string for the consensus value
   * for the n'th set.
   */
  static char *
  compute_nth_protocol_set(int n, int n_voters, const smartlist_t *votes)
  {
    const char *keyword;
    smartlist_t *proto_votes = smartlist_new();
    int threshold;
    switch (n) {
      case 0:
        keyword = "recommended-client-protocols";
        threshold = CEIL_DIV(n_voters, 2);
        break;
      case 1:
        keyword = "recommended-relay-protocols";
        threshold = CEIL_DIV(n_voters, 2);
        break;
      case 2:
        keyword = "required-client-protocols";
        threshold = CEIL_DIV(n_voters * 2, 3);
        break;
      case 3:
        keyword = "required-relay-protocols";
        threshold = CEIL_DIV(n_voters * 2, 3);
        break;
      default:
        tor_assert_unreached();
        return NULL;
    }
  
    SMARTLIST_FOREACH_BEGIN(votes, const networkstatus_t *, ns) {
      const char *v = get_nth_protocol_set_vote(n, ns);
      if (v)
        smartlist_add(proto_votes, (void*)v);
    } SMARTLIST_FOREACH_END(ns);
  
    char *protocols = protover_compute_vote(proto_votes, threshold);
    smartlist_free(proto_votes);
  
    char *result = NULL;
    tor_asprintf(&result, "%s %s\n", keyword, protocols);
    tor_free(protocols);
  
    return result;
  }
  
  /** Given a list of vote networkstatus_t in <b>votes</b>, our public
   * authority <b>identity_key</b>, our private authority <b>signing_key</b>,
   * and the number of <b>total_authorities</b> that we believe exist in our
   * voting quorum, generate the text of a new v3 consensus or microdescriptor
   * consensus (depending on <b>flavor</b>), and return the value in a newly
   * allocated string.
   *
   * Note: this function DOES NOT check whether the votes are from
   * recognized authorities.   (dirvote_add_vote does that.)
   *
   * <strong>WATCH OUT</strong>: You need to think before you change the
   * behavior of this function, or of the functions it calls! If some
   * authorities compute the consensus with a different algorithm than
   * others, they will not reach the same result, and they will not all
   * sign the same thing!  If you really need to change the algorithm
   * here, you should allocate a new "consensus_method" for the new
   * behavior, and make the new behavior conditional on a new-enough
   * consensus_method.
   **/
  STATIC char *
  networkstatus_compute_consensus(smartlist_t *votes,
                                  int total_authorities,
                                  crypto_pk_t *identity_key,
                                  crypto_pk_t *signing_key,
                                  const char *legacy_id_key_digest,
                                  crypto_pk_t *legacy_signing_key,
                                  consensus_flavor_t flavor)
  {
    smartlist_t *chunks;
    char *result = NULL;
    int consensus_method;
    time_t valid_after, fresh_until, valid_until;
    int vote_seconds, dist_seconds;
    char *client_versions = NULL, *server_versions = NULL;
    smartlist_t *flags;
    const char *flavor_name;
    uint32_t max_unmeasured_bw_kb = DEFAULT_MAX_UNMEASURED_BW_KB;
    int64_t G, M, E, D, T; /* For bandwidth weights */
    const routerstatus_format_type_t rs_format =
      flavor == FLAV_NS ? NS_V3_CONSENSUS : NS_V3_CONSENSUS_MICRODESC;
    char *params = NULL;
    char *packages = NULL;
    int added_weights = 0;
    dircollator_t *collator = NULL;
    smartlist_t *param_list = NULL;
  
    tor_assert(flavor == FLAV_NS || flavor == FLAV_MICRODESC);
    tor_assert(total_authorities >= smartlist_len(votes));
    tor_assert(total_authorities > 0);
  
    flavor_name = networkstatus_get_flavor_name(flavor);
  
    if (!smartlist_len(votes)) {
      log_warn(LD_DIR, "Can't compute a consensus from no votes.");
      return NULL;
    }
    flags = smartlist_new();
  
    consensus_method = compute_consensus_method(votes);
    if (consensus_method_is_supported(consensus_method)) {
      log_info(LD_DIR, "Generating consensus using method %d.",
               consensus_method);
    } else {
      log_warn(LD_DIR, "The other authorities will use consensus method %d, "
               "which I don't support.  Maybe I should upgrade!",
               consensus_method);
      consensus_method = MAX_SUPPORTED_CONSENSUS_METHOD;
    }
  
    if (consensus_method >= MIN_METHOD_FOR_INIT_BW_WEIGHTS_ONE) {
      /* It's smarter to initialize these weights to 1, so that later on,
       * we can't accidentally divide by zero. */
      G = M = E = D = 1;
      T = 4;
    } else {
      /* ...but originally, they were set to zero. */
      G = M = E = D = T = 0;
    }
  
    /* Compute medians of time-related things, and figure out how many
     * routers we might need to talk about. */
    {
      int n_votes = smartlist_len(votes);
      time_t *va_times = tor_calloc(n_votes, sizeof(time_t));
      time_t *fu_times = tor_calloc(n_votes, sizeof(time_t));
      time_t *vu_times = tor_calloc(n_votes, sizeof(time_t));
      int *votesec_list = tor_calloc(n_votes, sizeof(int));
      int *distsec_list = tor_calloc(n_votes, sizeof(int));
      int n_versioning_clients = 0, n_versioning_servers = 0;
      smartlist_t *combined_client_versions = smartlist_new();
      smartlist_t *combined_server_versions = smartlist_new();
  
      SMARTLIST_FOREACH_BEGIN(votes, networkstatus_t *, v) {
        tor_assert(v->type == NS_TYPE_VOTE);
        va_times[v_sl_idx] = v->valid_after;
        fu_times[v_sl_idx] = v->fresh_until;
        vu_times[v_sl_idx] = v->valid_until;
        votesec_list[v_sl_idx] = v->vote_seconds;
        distsec_list[v_sl_idx] = v->dist_seconds;
        if (v->client_versions) {
          smartlist_t *cv = smartlist_new();
          ++n_versioning_clients;
          smartlist_split_string(cv, v->client_versions, ",",
                                 SPLIT_SKIP_SPACE|SPLIT_IGNORE_BLANK, 0);
          sort_version_list(cv, 1);
          smartlist_add_all(combined_client_versions, cv);
          smartlist_free(cv); /* elements get freed later. */
        }
        if (v->server_versions) {
          smartlist_t *sv = smartlist_new();
          ++n_versioning_servers;
          smartlist_split_string(sv, v->server_versions, ",",
                                 SPLIT_SKIP_SPACE|SPLIT_IGNORE_BLANK, 0);
          sort_version_list(sv, 1);
          smartlist_add_all(combined_server_versions, sv);
          smartlist_free(sv); /* elements get freed later. */
        }
        SMARTLIST_FOREACH(v->known_flags, const char *, cp,
                          smartlist_add_strdup(flags, cp));
      } SMARTLIST_FOREACH_END(v);
      valid_after = median_time(va_times, n_votes);
      fresh_until = median_time(fu_times, n_votes);
      valid_until = median_time(vu_times, n_votes);
      vote_seconds = median_int(votesec_list, n_votes);
      dist_seconds = median_int(distsec_list, n_votes);
  
      tor_assert(valid_after +
                 (get_options()->TestingTorNetwork ?
                  MIN_VOTE_INTERVAL_TESTING : MIN_VOTE_INTERVAL) <= fresh_until);
      tor_assert(fresh_until +
                 (get_options()->TestingTorNetwork ?
                  MIN_VOTE_INTERVAL_TESTING : MIN_VOTE_INTERVAL) <= valid_until);
      tor_assert(vote_seconds >= MIN_VOTE_SECONDS);
      tor_assert(dist_seconds >= MIN_DIST_SECONDS);
  
      server_versions = compute_consensus_versions_list(combined_server_versions,
                                                        n_versioning_servers);
      client_versions = compute_consensus_versions_list(combined_client_versions,
                                                        n_versioning_clients);
      packages = compute_consensus_package_lines(votes);
  
      SMARTLIST_FOREACH(combined_server_versions, char *, cp, tor_free(cp));
      SMARTLIST_FOREACH(combined_client_versions, char *, cp, tor_free(cp));
      smartlist_free(combined_server_versions);
      smartlist_free(combined_client_versions);
  
      smartlist_add_strdup(flags, "NoEdConsensus");
  
      smartlist_sort_strings(flags);
      smartlist_uniq_strings(flags);
  
      tor_free(va_times);
      tor_free(fu_times);
      tor_free(vu_times);
      tor_free(votesec_list);
      tor_free(distsec_list);
    }
  
    chunks = smartlist_new();
  
    {
      char va_buf[ISO_TIME_LEN+1], fu_buf[ISO_TIME_LEN+1],
        vu_buf[ISO_TIME_LEN+1];
      char *flaglist;
      format_iso_time(va_buf, valid_after);
      format_iso_time(fu_buf, fresh_until);
      format_iso_time(vu_buf, valid_until);
      flaglist = smartlist_join_strings(flags, " ", 0, NULL);
  
      smartlist_add_asprintf(chunks, "network-status-version 3%s%s\n"
                   "vote-status consensus\n",
                   flavor == FLAV_NS ? "" : " ",
                   flavor == FLAV_NS ? "" : flavor_name);
  
      smartlist_add_asprintf(chunks, "consensus-method %d\n",
                             consensus_method);
  
      smartlist_add_asprintf(chunks,
                   "valid-after %s\n"
                   "fresh-until %s\n"
                   "valid-until %s\n"
                   "voting-delay %d %d\n"
                   "client-versions %s\n"
                   "server-versions %s\n"
                   "%s" /* packages */
                   "known-flags %s\n",
                   va_buf, fu_buf, vu_buf,
                   vote_seconds, dist_seconds,
                   client_versions, server_versions,
                   packages,
                   flaglist);
  
      tor_free(flaglist);
    }
  
    {
      int num_dirauth = get_n_authorities(V3_DIRINFO);
      int idx;
      for (idx = 0; idx < 4; ++idx) {
        char *proto_line = compute_nth_protocol_set(idx, num_dirauth, votes);
        if (BUG(!proto_line))
          continue;
        smartlist_add(chunks, proto_line);
      }
    }
  
    param_list = dirvote_compute_params(votes, consensus_method,
                                        total_authorities);
    if (smartlist_len(param_list)) {
      params = smartlist_join_strings(param_list, " ", 0, NULL);
      smartlist_add_strdup(chunks, "params ");
      smartlist_add(chunks, params);
      smartlist_add_strdup(chunks, "\n");
    }
  
    {
      int num_dirauth = get_n_authorities(V3_DIRINFO);
      /* Default value of this is 2/3 of the total number of authorities. For
       * instance, if we have 9 dirauth, the default value is 6. The following
       * calculation will round it down. */
      int32_t num_srv_agreements =
        dirvote_get_intermediate_param_value(param_list,
                                             "AuthDirNumSRVAgreements",
                                             (num_dirauth * 2) / 3);
      /* Add the shared random value. */
      char *srv_lines = sr_get_string_for_consensus(votes, num_srv_agreements);
      if (srv_lines != NULL) {
        smartlist_add(chunks, srv_lines);
      }
    }
  
    /* Sort the votes. */
    smartlist_sort(votes, compare_votes_by_authority_id_);
    /* Add the authority sections. */
    {
      smartlist_t *dir_sources = smartlist_new();
      SMARTLIST_FOREACH_BEGIN(votes, networkstatus_t *, v) {
        dir_src_ent_t *e = tor_malloc_zero(sizeof(dir_src_ent_t));
        e->v = v;
        e->digest = get_voter(v)->identity_digest;
        e->is_legacy = 0;
        smartlist_add(dir_sources, e);
        if (!tor_digest_is_zero(get_voter(v)->legacy_id_digest)) {
          dir_src_ent_t *e_legacy = tor_malloc_zero(sizeof(dir_src_ent_t));
          e_legacy->v = v;
          e_legacy->digest = get_voter(v)->legacy_id_digest;
          e_legacy->is_legacy = 1;
          smartlist_add(dir_sources, e_legacy);
        }
      } SMARTLIST_FOREACH_END(v);
      smartlist_sort(dir_sources, compare_dir_src_ents_by_authority_id_);
  
      SMARTLIST_FOREACH_BEGIN(dir_sources, const dir_src_ent_t *, e) {
        char fingerprint[HEX_DIGEST_LEN+1];
        char votedigest[HEX_DIGEST_LEN+1];
        networkstatus_t *v = e->v;
        networkstatus_voter_info_t *voter = get_voter(v);
  
        base16_encode(fingerprint, sizeof(fingerprint), e->digest, DIGEST_LEN);
        base16_encode(votedigest, sizeof(votedigest), voter->vote_digest,
                      DIGEST_LEN);
  
        smartlist_add_asprintf(chunks,
                     "dir-source %s%s %s %s %s %d %d\n",
                     voter->nickname, e->is_legacy ? "-legacy" : "",
                     fingerprint, voter->address, fmt_addr32(voter->addr),
                     voter->dir_port,
                     voter->or_port);
        if (! e->is_legacy) {
          smartlist_add_asprintf(chunks,
                       "contact %s\n"
                       "vote-digest %s\n",
                       voter->contact,
                       votedigest);
        }
      } SMARTLIST_FOREACH_END(e);
      SMARTLIST_FOREACH(dir_sources, dir_src_ent_t *, e, tor_free(e));
      smartlist_free(dir_sources);
    }
  
    {
      char *max_unmeasured_param = NULL;
      /* XXXX Extract this code into a common function.  Or don't!  see #19011 */
      if (params) {
        if (strcmpstart(params, "maxunmeasuredbw=") == 0)
          max_unmeasured_param = params;
        else
          max_unmeasured_param = strstr(params, " maxunmeasuredbw=");
      }
      if (max_unmeasured_param) {
        int ok = 0;
        char *eq = strchr(max_unmeasured_param, '=');
        if (eq) {
          max_unmeasured_bw_kb = (uint32_t)
            tor_parse_ulong(eq+1, 10, 1, UINT32_MAX, &ok, NULL);
          if (!ok) {
            log_warn(LD_DIR, "Bad element '%s' in max unmeasured bw param",
                     escaped(max_unmeasured_param));
            max_unmeasured_bw_kb = DEFAULT_MAX_UNMEASURED_BW_KB;
          }
        }
      }
    }
  
    /* Add the actual router entries. */
    {
      int *size; /* size[j] is the number of routerstatuses in votes[j]. */
      int *flag_counts; /* The number of voters that list flag[j] for the
                         * currently considered router. */
      int i;
      smartlist_t *matching_descs = smartlist_new();
      smartlist_t *chosen_flags = smartlist_new();
      smartlist_t *versions = smartlist_new();
      smartlist_t *protocols = smartlist_new();
      smartlist_t *exitsummaries = smartlist_new();
      uint32_t *bandwidths_kb = tor_calloc(smartlist_len(votes),
                                           sizeof(uint32_t));
      uint32_t *measured_bws_kb = tor_calloc(smartlist_len(votes),
                                             sizeof(uint32_t));
      uint32_t *measured_guardfraction = tor_calloc(smartlist_len(votes),
                                                    sizeof(uint32_t));
      int num_bandwidths;
      int num_mbws;
      int num_guardfraction_inputs;
  
      int *n_voter_flags; /* n_voter_flags[j] is the number of flags that
                           * votes[j] knows about. */
      int *n_flag_voters; /* n_flag_voters[f] is the number of votes that care
                           * about flags[f]. */
      int **flag_map; /* flag_map[j][b] is an index f such that flag_map[f]
                       * is the same flag as votes[j]->known_flags[b]. */
      int *named_flag; /* Index of the flag "Named" for votes[j] */
      int *unnamed_flag; /* Index of the flag "Unnamed" for votes[j] */
      int n_authorities_measuring_bandwidth;
  
      strmap_t *name_to_id_map = strmap_new();
      char conflict[DIGEST_LEN];
      char unknown[DIGEST_LEN];
      memset(conflict, 0, sizeof(conflict));
      memset(unknown, 0xff, sizeof(conflict));
  
      size = tor_calloc(smartlist_len(votes), sizeof(int));
      n_voter_flags = tor_calloc(smartlist_len(votes), sizeof(int));
      n_flag_voters = tor_calloc(smartlist_len(flags), sizeof(int));
      flag_map = tor_calloc(smartlist_len(votes), sizeof(int *));
      named_flag = tor_calloc(smartlist_len(votes), sizeof(int));
      unnamed_flag = tor_calloc(smartlist_len(votes), sizeof(int));
      for (i = 0; i < smartlist_len(votes); ++i)
        unnamed_flag[i] = named_flag[i] = -1;
  
      /* Build the flag indexes. Note that no vote can have more than 64 members
       * for known_flags, so no value will be greater than 63, so it's safe to
       * do UINT64_C(1) << index on these values.  But note also that
       * named_flag and unnamed_flag are initialized to -1, so we need to check
       * that they're actually set before doing UINT64_C(1) << index with
       * them.*/
      SMARTLIST_FOREACH_BEGIN(votes, networkstatus_t *, v) {
        flag_map[v_sl_idx] = tor_calloc(smartlist_len(v->known_flags),
                                        sizeof(int));
        if (smartlist_len(v->known_flags) > MAX_KNOWN_FLAGS_IN_VOTE) {
          log_warn(LD_BUG, "Somehow, a vote has %d entries in known_flags",
                   smartlist_len(v->known_flags));
        }
        SMARTLIST_FOREACH_BEGIN(v->known_flags, const char *, fl) {
          int p = smartlist_string_pos(flags, fl);
          tor_assert(p >= 0);
          flag_map[v_sl_idx][fl_sl_idx] = p;
          ++n_flag_voters[p];
          if (!strcmp(fl, "Named"))
            named_flag[v_sl_idx] = fl_sl_idx;
          if (!strcmp(fl, "Unnamed"))
            unnamed_flag[v_sl_idx] = fl_sl_idx;
        } SMARTLIST_FOREACH_END(fl);
        n_voter_flags[v_sl_idx] = smartlist_len(v->known_flags);
        size[v_sl_idx] = smartlist_len(v->routerstatus_list);
      } SMARTLIST_FOREACH_END(v);
  
      /* Named and Unnamed get treated specially */
      {
        SMARTLIST_FOREACH_BEGIN(votes, networkstatus_t *, v) {
          uint64_t nf;
          if (named_flag[v_sl_idx]<0)
            continue;
          nf = UINT64_C(1) << named_flag[v_sl_idx];
          SMARTLIST_FOREACH_BEGIN(v->routerstatus_list,
                                  vote_routerstatus_t *, rs) {
  
            if ((rs->flags & nf) != 0) {
              const char *d = strmap_get_lc(name_to_id_map, rs->status.nickname);
              if (!d) {
                /* We have no name officially mapped to this digest. */
                strmap_set_lc(name_to_id_map, rs->status.nickname,
                              rs->status.identity_digest);
              } else if (d != conflict &&
                  fast_memcmp(d, rs->status.identity_digest, DIGEST_LEN)) {
                /* Authorities disagree about this nickname. */
                strmap_set_lc(name_to_id_map, rs->status.nickname, conflict);
              } else {
                /* It's already a conflict, or it's already this ID. */
              }
            }
          } SMARTLIST_FOREACH_END(rs);
        } SMARTLIST_FOREACH_END(v);
  
        SMARTLIST_FOREACH_BEGIN(votes, networkstatus_t *, v) {
          uint64_t uf;
          if (unnamed_flag[v_sl_idx]<0)
            continue;
          uf = UINT64_C(1) << unnamed_flag[v_sl_idx];
          SMARTLIST_FOREACH_BEGIN(v->routerstatus_list,
                                  vote_routerstatus_t *, rs) {
            if ((rs->flags & uf) != 0) {
              const char *d = strmap_get_lc(name_to_id_map, rs->status.nickname);
              if (d == conflict || d == unknown) {
                /* Leave it alone; we know what it is. */
              } else if (!d) {
                /* We have no name officially mapped to this digest. */
                strmap_set_lc(name_to_id_map, rs->status.nickname, unknown);
              } else if (fast_memeq(d, rs->status.identity_digest, DIGEST_LEN)) {
                /* Authorities disagree about this nickname. */
                strmap_set_lc(name_to_id_map, rs->status.nickname, conflict);
              } else {
                /* It's mapped to a different name. */
              }
            }
          } SMARTLIST_FOREACH_END(rs);
        } SMARTLIST_FOREACH_END(v);
      }
  
      /* We need to know how many votes measure bandwidth. */
      n_authorities_measuring_bandwidth = 0;
      SMARTLIST_FOREACH(votes, const networkstatus_t *, v,
         if (v->has_measured_bws) {
           ++n_authorities_measuring_bandwidth;
         }
      );
  
      /* Populate the collator */
      collator = dircollator_new(smartlist_len(votes), total_authorities);
      SMARTLIST_FOREACH_BEGIN(votes, networkstatus_t *, v) {
        dircollator_add_vote(collator, v);
      } SMARTLIST_FOREACH_END(v);
  
      dircollator_collate(collator, consensus_method);
  
      /* Now go through all the votes */
      flag_counts = tor_calloc(smartlist_len(flags), sizeof(int));
      const int num_routers = dircollator_n_routers(collator);
      for (i = 0; i < num_routers; ++i) {
        vote_routerstatus_t **vrs_lst =
          dircollator_get_votes_for_router(collator, i);
  
        vote_routerstatus_t *rs;
        routerstatus_t rs_out;
        const char *current_rsa_id = NULL;
        const char *chosen_version;
        const char *chosen_protocol_list;
        const char *chosen_name = NULL;
        int exitsummary_disagreement = 0;
        int is_named = 0, is_unnamed = 0, is_running = 0, is_valid = 0;
        int is_guard = 0, is_exit = 0, is_bad_exit = 0;
        int naming_conflict = 0;
        int n_listing = 0;
        char microdesc_digest[DIGEST256_LEN];
        tor_addr_port_t alt_orport = {TOR_ADDR_NULL, 0};
  
        memset(flag_counts, 0, sizeof(int)*smartlist_len(flags));
        smartlist_clear(matching_descs);
        smartlist_clear(chosen_flags);
        smartlist_clear(versions);
        smartlist_clear(protocols);
        num_bandwidths = 0;
        num_mbws = 0;
        num_guardfraction_inputs = 0;
        int ed_consensus = 0;
        const uint8_t *ed_consensus_val = NULL;
  
        /* Okay, go through all the entries for this digest. */
        for (int voter_idx = 0; voter_idx < smartlist_len(votes); ++voter_idx) {
          if (vrs_lst[voter_idx] == NULL)
            continue; /* This voter had nothing to say about this entry. */
          rs = vrs_lst[voter_idx];
          ++n_listing;
  
          current_rsa_id = rs->status.identity_digest;
  
          smartlist_add(matching_descs, rs);
          if (rs->version && rs->version[0])
            smartlist_add(versions, rs->version);
  
          if (rs->protocols) {
            /* We include this one even if it's empty: voting for an
             * empty protocol list actually is meaningful. */
            smartlist_add(protocols, rs->protocols);
          }
  
          /* Tally up all the flags. */
          for (int flag = 0; flag < n_voter_flags[voter_idx]; ++flag) {
            if (rs->flags & (UINT64_C(1) << flag))
              ++flag_counts[flag_map[voter_idx][flag]];
          }
          if (named_flag[voter_idx] >= 0 &&
              (rs->flags & (UINT64_C(1) << named_flag[voter_idx]))) {
            if (chosen_name && strcmp(chosen_name, rs->status.nickname)) {
              log_notice(LD_DIR, "Conflict on naming for router: %s vs %s",
                         chosen_name, rs->status.nickname);
              naming_conflict = 1;
            }
            chosen_name = rs->status.nickname;
          }
  
          /* Count guardfraction votes and note down the values. */
          if (rs->status.has_guardfraction) {
            measured_guardfraction[num_guardfraction_inputs++] =
              rs->status.guardfraction_percentage;
          }
  
          /* count bandwidths */
          if (rs->has_measured_bw)
            measured_bws_kb[num_mbws++] = rs->measured_bw_kb;
  
          if (rs->status.has_bandwidth)
            bandwidths_kb[num_bandwidths++] = rs->status.bandwidth_kb;
  
          /* Count number for which ed25519 is canonical. */
          if (rs->ed25519_reflects_consensus) {
            ++ed_consensus;
            if (ed_consensus_val) {
              tor_assert(fast_memeq(ed_consensus_val, rs->ed25519_id,
                                    ED25519_PUBKEY_LEN));
            } else {
              ed_consensus_val = rs->ed25519_id;
            }
          }
        }
  
        /* We don't include this router at all unless more than half of
         * the authorities we believe in list it. */
        if (n_listing <= total_authorities/2)
          continue;
  
        if (ed_consensus > 0) {
          if (ed_consensus <= total_authorities / 2) {
            log_warn(LD_BUG, "Not enough entries had ed_consensus set; how "
                     "can we have a consensus of %d?", ed_consensus);
          }
        }
  
        /* The clangalyzer can't figure out that this will never be NULL
         * if n_listing is at least 1 */
        tor_assert(current_rsa_id);
  
        /* Figure out the most popular opinion of what the most recent
         * routerinfo and its contents are. */
        memset(microdesc_digest, 0, sizeof(microdesc_digest));
        rs = compute_routerstatus_consensus(matching_descs, consensus_method,
                                            microdesc_digest, &alt_orport);
        /* Copy bits of that into rs_out. */
        memset(&rs_out, 0, sizeof(rs_out));
        tor_assert(fast_memeq(current_rsa_id,
                              rs->status.identity_digest,DIGEST_LEN));
        memcpy(rs_out.identity_digest, current_rsa_id, DIGEST_LEN);
        memcpy(rs_out.descriptor_digest, rs->status.descriptor_digest,
               DIGEST_LEN);
        rs_out.addr = rs->status.addr;
        rs_out.published_on = rs->status.published_on;
        rs_out.dir_port = rs->status.dir_port;
        rs_out.or_port = rs->status.or_port;
        tor_addr_copy(&rs_out.ipv6_addr, &alt_orport.addr);
        rs_out.ipv6_orport = alt_orport.port;
        rs_out.has_bandwidth = 0;
        rs_out.has_exitsummary = 0;
  
        if (chosen_name && !naming_conflict) {
          strlcpy(rs_out.nickname, chosen_name, sizeof(rs_out.nickname));
        } else {
          strlcpy(rs_out.nickname, rs->status.nickname, sizeof(rs_out.nickname));
        }
  
        {
          const char *d = strmap_get_lc(name_to_id_map, rs_out.nickname);
          if (!d) {
            is_named = is_unnamed = 0;
          } else if (fast_memeq(d, current_rsa_id, DIGEST_LEN)) {
            is_named = 1; is_unnamed = 0;
          } else {
            is_named = 0; is_unnamed = 1;
          }
        }
  
        /* Set the flags. */
        smartlist_add(chosen_flags, (char*)"s"); /* for the start of the line. */
        SMARTLIST_FOREACH_BEGIN(flags, const char *, fl) {
          if (!strcmp(fl, "Named")) {
            if (is_named)
              smartlist_add(chosen_flags, (char*)fl);
          } else if (!strcmp(fl, "Unnamed")) {
            if (is_unnamed)
              smartlist_add(chosen_flags, (char*)fl);
          } else if (!strcmp(fl, "NoEdConsensus")) {
            if (ed_consensus <= total_authorities/2)
              smartlist_add(chosen_flags, (char*)fl);
          } else {
            if (flag_counts[fl_sl_idx] > n_flag_voters[fl_sl_idx]/2) {
              smartlist_add(chosen_flags, (char*)fl);
              if (!strcmp(fl, "Exit"))
                is_exit = 1;
              else if (!strcmp(fl, "Guard"))
                is_guard = 1;
              else if (!strcmp(fl, "Running"))
                is_running = 1;
              else if (!strcmp(fl, "BadExit"))
                is_bad_exit = 1;
              else if (!strcmp(fl, "Valid"))
                is_valid = 1;
            }
          }
        } SMARTLIST_FOREACH_END(fl);
  
        /* Starting with consensus method 4 we do not list servers
         * that are not running in a consensus.  See Proposal 138 */
        if (!is_running)
          continue;
  
        /* Starting with consensus method 24, we don't list servers
         * that are not valid in a consensus.  See Proposal 272 */
        if (!is_valid)
          continue;
  
        /* Pick the version. */
        if (smartlist_len(versions)) {
          sort_version_list(versions, 0);
          chosen_version = get_most_frequent_member(versions);
        } else {
          chosen_version = NULL;
        }
  
        /* Pick the protocol list */
        if (smartlist_len(protocols)) {
          smartlist_sort_strings(protocols);
          chosen_protocol_list = get_most_frequent_member(protocols);
        } else {
          chosen_protocol_list = NULL;
        }
  
        /* If it's a guard and we have enough guardfraction votes,
           calculate its consensus guardfraction value. */
        if (is_guard && num_guardfraction_inputs > 2) {
          rs_out.has_guardfraction = 1;
          rs_out.guardfraction_percentage = median_uint32(measured_guardfraction,
                                                       num_guardfraction_inputs);
          /* final value should be an integer percentage! */
          tor_assert(rs_out.guardfraction_percentage <= 100);
        }
  
        /* Pick a bandwidth */
        if (num_mbws > 2) {
          rs_out.has_bandwidth = 1;
          rs_out.bw_is_unmeasured = 0;
          rs_out.bandwidth_kb = median_uint32(measured_bws_kb, num_mbws);
        } else if (num_bandwidths > 0) {
          rs_out.has_bandwidth = 1;
          rs_out.bw_is_unmeasured = 1;
          rs_out.bandwidth_kb = median_uint32(bandwidths_kb, num_bandwidths);
          if (n_authorities_measuring_bandwidth > 2) {
            /* Cap non-measured bandwidths. */
            if (rs_out.bandwidth_kb > max_unmeasured_bw_kb) {
              rs_out.bandwidth_kb = max_unmeasured_bw_kb;
            }
          }
        }
  
        /* Fix bug 2203: Do not count BadExit nodes as Exits for bw weights */
        is_exit = is_exit && !is_bad_exit;
  
        /* Update total bandwidth weights with the bandwidths of this router. */
        {
          update_total_bandwidth_weights(&rs_out,
                                         is_exit, is_guard,
                                         &G, &M, &E, &D, &T);
        }
  
        /* Ok, we already picked a descriptor digest we want to list
         * previously.  Now we want to use the exit policy summary from
         * that descriptor.  If everybody plays nice all the voters who
         * listed that descriptor will have the same summary.  If not then
         * something is fishy and we'll use the most common one (breaking
         * ties in favor of lexicographically larger one (only because it
         * lets me reuse more existing code)).
         *
         * The other case that can happen is that no authority that voted
         * for that descriptor has an exit policy summary.  That's
         * probably quite unlikely but can happen.  In that case we use
         * the policy that was most often listed in votes, again breaking
         * ties like in the previous case.
         */
        {
          /* Okay, go through all the votes for this router.  We prepared
           * that list previously */
          const char *chosen_exitsummary = NULL;
          smartlist_clear(exitsummaries);
          SMARTLIST_FOREACH_BEGIN(matching_descs, vote_routerstatus_t *, vsr) {
            /* Check if the vote where this status comes from had the
             * proper descriptor */
            tor_assert(fast_memeq(rs_out.identity_digest,
                               vsr->status.identity_digest,
                               DIGEST_LEN));
            if (vsr->status.has_exitsummary &&
                 fast_memeq(rs_out.descriptor_digest,
                         vsr->status.descriptor_digest,
                         DIGEST_LEN)) {
              tor_assert(vsr->status.exitsummary);
              smartlist_add(exitsummaries, vsr->status.exitsummary);
              if (!chosen_exitsummary) {
                chosen_exitsummary = vsr->status.exitsummary;
              } else if (strcmp(chosen_exitsummary, vsr->status.exitsummary)) {
                /* Great.  There's disagreement among the voters.  That
                 * really shouldn't be */
                exitsummary_disagreement = 1;
              }
            }
          } SMARTLIST_FOREACH_END(vsr);
  
          if (exitsummary_disagreement) {
            char id[HEX_DIGEST_LEN+1];
            char dd[HEX_DIGEST_LEN+1];
            base16_encode(id, sizeof(dd), rs_out.identity_digest, DIGEST_LEN);
            base16_encode(dd, sizeof(dd), rs_out.descriptor_digest, DIGEST_LEN);
            log_warn(LD_DIR, "The voters disagreed on the exit policy summary "
                     " for router %s with descriptor %s.  This really shouldn't"
                     " have happened.", id, dd);
  
            smartlist_sort_strings(exitsummaries);
            chosen_exitsummary = get_most_frequent_member(exitsummaries);
          } else if (!chosen_exitsummary) {
            char id[HEX_DIGEST_LEN+1];
            char dd[HEX_DIGEST_LEN+1];
            base16_encode(id, sizeof(dd), rs_out.identity_digest, DIGEST_LEN);
            base16_encode(dd, sizeof(dd), rs_out.descriptor_digest, DIGEST_LEN);
            log_warn(LD_DIR, "Not one of the voters that made us select"
                     "descriptor %s for router %s had an exit policy"
                     "summary", dd, id);
  
            /* Ok, none of those voting for the digest we chose had an
             * exit policy for us.  Well, that kinda sucks.
             */
            smartlist_clear(exitsummaries);
            SMARTLIST_FOREACH(matching_descs, vote_routerstatus_t *, vsr, {
              if (vsr->status.has_exitsummary)
                smartlist_add(exitsummaries, vsr->status.exitsummary);
            });
            smartlist_sort_strings(exitsummaries);
            chosen_exitsummary = get_most_frequent_member(exitsummaries);
  
            if (!chosen_exitsummary)
              log_warn(LD_DIR, "Wow, not one of the voters had an exit "
                       "policy summary for %s.  Wow.", id);
          }
  
          if (chosen_exitsummary) {
            rs_out.has_exitsummary = 1;
            /* yea, discards the const */
            rs_out.exitsummary = (char *)chosen_exitsummary;
          }
        }
  
        if (flavor == FLAV_MICRODESC &&
            tor_digest256_is_zero(microdesc_digest)) {
          /* With no microdescriptor digest, we omit the entry entirely. */
          continue;
        }
  
        {
          char *buf;
          /* Okay!! Now we can write the descriptor... */
          /*     First line goes into "buf". */
          buf = routerstatus_format_entry(&rs_out, NULL, NULL,
                                          rs_format, consensus_method, NULL);
          if (buf)
            smartlist_add(chunks, buf);
        }
        /*     Now an m line, if applicable. */
        if (flavor == FLAV_MICRODESC &&
            !tor_digest256_is_zero(microdesc_digest)) {
          char m[BASE64_DIGEST256_LEN+1];
          digest256_to_base64(m, microdesc_digest);
          smartlist_add_asprintf(chunks, "m %s\n", m);
        }
        /*     Next line is all flags.  The "\n" is missing. */
        smartlist_add(chunks,
                      smartlist_join_strings(chosen_flags, " ", 0, NULL));
        /*     Now the version line. */
        if (chosen_version) {
          smartlist_add_strdup(chunks, "\nv ");
          smartlist_add_strdup(chunks, chosen_version);
        }
        smartlist_add_strdup(chunks, "\n");
        if (chosen_protocol_list &&
            consensus_method >= MIN_METHOD_FOR_RS_PROTOCOLS) {
          smartlist_add_asprintf(chunks, "pr %s\n", chosen_protocol_list);
        }
        /*     Now the weight line. */
        if (rs_out.has_bandwidth) {
          char *guardfraction_str = NULL;
          int unmeasured = rs_out.bw_is_unmeasured;
  
          /* If we have guardfraction info, include it in the 'w' line. */
          if (rs_out.has_guardfraction) {
            tor_asprintf(&guardfraction_str,
                         " GuardFraction=%u", rs_out.guardfraction_percentage);
          }
          smartlist_add_asprintf(chunks, "w Bandwidth=%d%s%s\n",
                                 rs_out.bandwidth_kb,
                                 unmeasured?" Unmeasured=1":"",
                                 guardfraction_str ? guardfraction_str : "");
  
          tor_free(guardfraction_str);
        }
  
        /*     Now the exitpolicy summary line. */
        if (rs_out.has_exitsummary && flavor == FLAV_NS) {
          smartlist_add_asprintf(chunks, "p %s\n", rs_out.exitsummary);
        }
  
        /* And the loop is over and we move on to the next router */
      }
  
      tor_free(size);
      tor_free(n_voter_flags);
      tor_free(n_flag_voters);
      for (i = 0; i < smartlist_len(votes); ++i)
        tor_free(flag_map[i]);
      tor_free(flag_map);
      tor_free(flag_counts);
      tor_free(named_flag);
      tor_free(unnamed_flag);
      strmap_free(name_to_id_map, NULL);
      smartlist_free(matching_descs);
      smartlist_free(chosen_flags);
      smartlist_free(versions);
      smartlist_free(protocols);
      smartlist_free(exitsummaries);
      tor_free(bandwidths_kb);
      tor_free(measured_bws_kb);
      tor_free(measured_guardfraction);
    }
  
    /* Mark the directory footer region */
    smartlist_add_strdup(chunks, "directory-footer\n");
  
    {
      int64_t weight_scale = BW_WEIGHT_SCALE;
      char *bw_weight_param = NULL;
  
      // Parse params, extract BW_WEIGHT_SCALE if present
      // DO NOT use consensus_param_bw_weight_scale() in this code!
      // The consensus is not formed yet!
      /* XXXX Extract this code into a common function. Or not: #19011. */
      if (params) {
        if (strcmpstart(params, "bwweightscale=") == 0)
          bw_weight_param = params;
        else
          bw_weight_param = strstr(params, " bwweightscale=");
      }
  
      if (bw_weight_param) {
        int ok=0;
        char *eq = strchr(bw_weight_param, '=');
        if (eq) {
          weight_scale = tor_parse_long(eq+1, 10, 1, INT32_MAX, &ok,
                                           NULL);
          if (!ok) {
            log_warn(LD_DIR, "Bad element '%s' in bw weight param",
                escaped(bw_weight_param));
            weight_scale = BW_WEIGHT_SCALE;
          }
        } else {
          log_warn(LD_DIR, "Bad element '%s' in bw weight param",
              escaped(bw_weight_param));
          weight_scale = BW_WEIGHT_SCALE;
        }
      }
  
      added_weights = networkstatus_compute_bw_weights_v10(chunks, G, M, E, D,
                                                           T, weight_scale);
    }
  
    /* Add a signature. */
    {
      char digest[DIGEST256_LEN];
      char fingerprint[HEX_DIGEST_LEN+1];
      char signing_key_fingerprint[HEX_DIGEST_LEN+1];
      digest_algorithm_t digest_alg =
        flavor == FLAV_NS ? DIGEST_SHA1 : DIGEST_SHA256;
      size_t digest_len =
        flavor == FLAV_NS ? DIGEST_LEN : DIGEST256_LEN;
      const char *algname = crypto_digest_algorithm_get_name(digest_alg);
      char *signature;
  
      smartlist_add_strdup(chunks, "directory-signature ");
  
      /* Compute the hash of the chunks. */
      crypto_digest_smartlist(digest, digest_len, chunks, "", digest_alg);
  
      /* Get the fingerprints */
      crypto_pk_get_fingerprint(identity_key, fingerprint, 0);
      crypto_pk_get_fingerprint(signing_key, signing_key_fingerprint, 0);
  
      /* add the junk that will go at the end of the line. */
      if (flavor == FLAV_NS) {
        smartlist_add_asprintf(chunks, "%s %s\n", fingerprint,
                     signing_key_fingerprint);
      } else {
        smartlist_add_asprintf(chunks, "%s %s %s\n",
                     algname, fingerprint,
                     signing_key_fingerprint);
      }
      /* And the signature. */
      if (!(signature = router_get_dirobj_signature(digest, digest_len,
                                                    signing_key))) {
        log_warn(LD_BUG, "Couldn't sign consensus networkstatus.");
        goto done;
      }
      smartlist_add(chunks, signature);
  
      if (legacy_id_key_digest && legacy_signing_key) {
        smartlist_add_strdup(chunks, "directory-signature ");
        base16_encode(fingerprint, sizeof(fingerprint),
                      legacy_id_key_digest, DIGEST_LEN);
        crypto_pk_get_fingerprint(legacy_signing_key,
                                  signing_key_fingerprint, 0);
        if (flavor == FLAV_NS) {
          smartlist_add_asprintf(chunks, "%s %s\n", fingerprint,
                       signing_key_fingerprint);
        } else {
          smartlist_add_asprintf(chunks, "%s %s %s\n",
                       algname, fingerprint,
                       signing_key_fingerprint);
        }
  
        if (!(signature = router_get_dirobj_signature(digest, digest_len,
                                                      legacy_signing_key))) {
          log_warn(LD_BUG, "Couldn't sign consensus networkstatus.");
          goto done;
        }
        smartlist_add(chunks, signature);
      }
    }
  
    result = smartlist_join_strings(chunks, "", 0, NULL);
  
    {
      networkstatus_t *c;
      if (!(c = networkstatus_parse_vote_from_string(result, strlen(result),
                                                     NULL,
                                                     NS_TYPE_CONSENSUS))) {
        log_err(LD_BUG, "Generated a networkstatus consensus we couldn't "
                "parse.");
        tor_free(result);
        goto done;
      }
      // Verify balancing parameters
      if (added_weights) {
        networkstatus_verify_bw_weights(c, consensus_method);
      }
      networkstatus_vote_free(c);
    }
  
   done:
  
    dircollator_free(collator);
    tor_free(client_versions);
    tor_free(server_versions);
    tor_free(packages);
    SMARTLIST_FOREACH(flags, char *, cp, tor_free(cp));
    smartlist_free(flags);
    SMARTLIST_FOREACH(chunks, char *, cp, tor_free(cp));
    smartlist_free(chunks);
    SMARTLIST_FOREACH(param_list, char *, cp, tor_free(cp));
    smartlist_free(param_list);
  
    return result;
  }
  
  /** Given a list of networkstatus_t for each vote, return a newly allocated
   * string containing the "package" lines for the vote. */
  STATIC char *
  compute_consensus_package_lines(smartlist_t *votes)
  {
    const int n_votes = smartlist_len(votes);
  
    /* This will be a map from "packagename version" strings to arrays
     * of const char *, with the i'th member of the array corresponding to the
     * package line from the i'th vote.
     */
    strmap_t *package_status = strmap_new();
  
    SMARTLIST_FOREACH_BEGIN(votes, networkstatus_t *, v) {
      if (! v->package_lines)
        continue;
      SMARTLIST_FOREACH_BEGIN(v->package_lines, const char *, line) {
        if (! validate_recommended_package_line(line))
          continue;
  
        /* Skip 'cp' to the second space in the line. */
        const char *cp = strchr(line, ' ');
        if (!cp) continue;
        ++cp;
        cp = strchr(cp, ' ');
        if (!cp) continue;
  
        char *key = tor_strndup(line, cp - line);
  
        const char **status = strmap_get(package_status, key);
        if (!status) {
          status = tor_calloc(n_votes, sizeof(const char *));
          strmap_set(package_status, key, status);
        }
        status[v_sl_idx] = line; /* overwrite old value */
        tor_free(key);
      } SMARTLIST_FOREACH_END(line);
    } SMARTLIST_FOREACH_END(v);
  
    smartlist_t *entries = smartlist_new(); /* temporary */
    smartlist_t *result_list = smartlist_new(); /* output */
    STRMAP_FOREACH(package_status, key, const char **, values) {
      int i, count=-1;
      for (i = 0; i < n_votes; ++i) {
        if (values[i])
          smartlist_add(entries, (void*) values[i]);
      }
      smartlist_sort_strings(entries);
      int n_voting_for_entry = smartlist_len(entries);
      const char *most_frequent =
        smartlist_get_most_frequent_string_(entries, &count);
  
      if (n_voting_for_entry >= 3 && count > n_voting_for_entry / 2) {
        smartlist_add_asprintf(result_list, "package %s\n", most_frequent);
      }
  
      smartlist_clear(entries);
  
    } STRMAP_FOREACH_END;
  
    smartlist_sort_strings(result_list);
  
    char *result = smartlist_join_strings(result_list, "", 0, NULL);
  
    SMARTLIST_FOREACH(result_list, char *, cp, tor_free(cp));
    smartlist_free(result_list);
    smartlist_free(entries);
    strmap_free(package_status, tor_free_);
  
    return result;
  }
  
  /** Given a consensus vote <b>target</b> and a set of detached signatures in
   * <b>sigs</b> that correspond to the same consensus, check whether there are
   * any new signatures in <b>src_voter_list</b> that should be added to
   * <b>target</b>. (A signature should be added if we have no signature for that
   * voter in <b>target</b> yet, or if we have no verifiable signature and the
   * new signature is verifiable.)  Return the number of signatures added or
   * changed, or -1 if the document signed by <b>sigs</b> isn't the same
   * document as <b>target</b>. */
  STATIC int
  networkstatus_add_detached_signatures(networkstatus_t *target,
                                        ns_detached_signatures_t *sigs,
                                        const char *source,
                                        int severity,
                                        const char **msg_out)
  {
    int r = 0;
    const char *flavor;
    smartlist_t *siglist;
    tor_assert(sigs);
    tor_assert(target);
    tor_assert(target->type == NS_TYPE_CONSENSUS);
  
    flavor = networkstatus_get_flavor_name(target->flavor);
  
    /* Do the times seem right? */
    if (target->valid_after != sigs->valid_after) {
      *msg_out = "Valid-After times do not match "
        "when adding detached signatures to consensus";
      return -1;
    }
    if (target->fresh_until != sigs->fresh_until) {
      *msg_out = "Fresh-until times do not match "
        "when adding detached signatures to consensus";
      return -1;
    }
    if (target->valid_until != sigs->valid_until) {
      *msg_out = "Valid-until times do not match "
        "when adding detached signatures to consensus";
      return -1;
    }
    siglist = strmap_get(sigs->signatures, flavor);
    if (!siglist) {
      *msg_out = "No signatures for given consensus flavor";
      return -1;
    }
  
    /** Make sure all the digests we know match, and at least one matches. */
    {
      common_digests_t *digests = strmap_get(sigs->digests, flavor);
      int n_matches = 0;
      int alg;
      if (!digests) {
        *msg_out = "No digests for given consensus flavor";
        return -1;
      }
      for (alg = DIGEST_SHA1; alg < N_COMMON_DIGEST_ALGORITHMS; ++alg) {
        if (!fast_mem_is_zero(digests->d[alg], DIGEST256_LEN)) {
          if (fast_memeq(target->digests.d[alg], digests->d[alg],
                         DIGEST256_LEN)) {
            ++n_matches;
          } else {
            *msg_out = "Mismatched digest.";
            return -1;
          }
        }
      }
      if (!n_matches) {
        *msg_out = "No recognized digests for given consensus flavor";
      }
    }
  
    /* For each voter in src... */
    SMARTLIST_FOREACH_BEGIN(siglist, document_signature_t *, sig) {
      char voter_identity[HEX_DIGEST_LEN+1];
      networkstatus_voter_info_t *target_voter =
        networkstatus_get_voter_by_id(target, sig->identity_digest);
      authority_cert_t *cert = NULL;
      const char *algorithm;
      document_signature_t *old_sig = NULL;
  
      algorithm = crypto_digest_algorithm_get_name(sig->alg);
  
      base16_encode(voter_identity, sizeof(voter_identity),
                    sig->identity_digest, DIGEST_LEN);
      log_info(LD_DIR, "Looking at signature from %s using %s", voter_identity,
               algorithm);
      /* If the target doesn't know about this voter, then forget it. */
      if (!target_voter) {
        log_info(LD_DIR, "We do not know any voter with ID %s", voter_identity);
        continue;
      }
  
      old_sig = networkstatus_get_voter_sig_by_alg(target_voter, sig->alg);
  
      /* If the target already has a good signature from this voter, then skip
       * this one. */
      if (old_sig && old_sig->good_signature) {
        log_info(LD_DIR, "We already have a good signature from %s using %s",
                 voter_identity, algorithm);
        continue;
      }
  
      /* Try checking the signature if we haven't already. */
      if (!sig->good_signature && !sig->bad_signature) {
        cert = authority_cert_get_by_digests(sig->identity_digest,
                                             sig->signing_key_digest);
        if (cert) {
          /* Not checking the return value here, since we are going to look
           * at the status of sig->good_signature in a moment. */
          (void) networkstatus_check_document_signature(target, sig, cert);
        }
      }
  
      /* If this signature is good, or we don't have any signature yet,
       * then maybe add it. */
      if (sig->good_signature || !old_sig || old_sig->bad_signature) {
        log_info(LD_DIR, "Adding signature from %s with %s", voter_identity,
                 algorithm);
        tor_log(severity, LD_DIR, "Added a signature for %s from %s.",
            target_voter->nickname, source);
        ++r;
        if (old_sig) {
          smartlist_remove(target_voter->sigs, old_sig);
          document_signature_free(old_sig);
        }
        smartlist_add(target_voter->sigs, document_signature_dup(sig));
      } else {
        log_info(LD_DIR, "Not adding signature from %s", voter_identity);
      }
    } SMARTLIST_FOREACH_END(sig);
  
    return r;
  }
  
  /** Return a newly allocated string containing all the signatures on
   * <b>consensus</b> by all voters. If <b>for_detached_signatures</b> is true,
   * then the signatures will be put in a detached signatures document, so
   * prefix any non-NS-flavored signatures with "additional-signature" rather
   * than "directory-signature". */
  static char *
  networkstatus_format_signatures(networkstatus_t *consensus,
                                  int for_detached_signatures)
  {
    smartlist_t *elements;
    char buf[4096];
    char *result = NULL;
    int n_sigs = 0;
    const consensus_flavor_t flavor = consensus->flavor;
    const char *flavor_name = networkstatus_get_flavor_name(flavor);
    const char *keyword;
  
    if (for_detached_signatures && flavor != FLAV_NS)
      keyword = "additional-signature";
    else
      keyword = "directory-signature";
  
    elements = smartlist_new();
  
    SMARTLIST_FOREACH_BEGIN(consensus->voters, networkstatus_voter_info_t *, v) {
      SMARTLIST_FOREACH_BEGIN(v->sigs, document_signature_t *, sig) {
        char sk[HEX_DIGEST_LEN+1];
        char id[HEX_DIGEST_LEN+1];
        if (!sig->signature || sig->bad_signature)
          continue;
        ++n_sigs;
        base16_encode(sk, sizeof(sk), sig->signing_key_digest, DIGEST_LEN);
        base16_encode(id, sizeof(id), sig->identity_digest, DIGEST_LEN);
        if (flavor == FLAV_NS) {
          smartlist_add_asprintf(elements,
                       "%s %s %s\n-----BEGIN SIGNATURE-----\n",
                       keyword, id, sk);
        } else {
          const char *digest_name =
            crypto_digest_algorithm_get_name(sig->alg);
          smartlist_add_asprintf(elements,
                       "%s%s%s %s %s %s\n-----BEGIN SIGNATURE-----\n",
                       keyword,
                       for_detached_signatures ? " " : "",
                       for_detached_signatures ? flavor_name : "",
                       digest_name, id, sk);
        }
        base64_encode(buf, sizeof(buf), sig->signature, sig->signature_len,
                      BASE64_ENCODE_MULTILINE);
        strlcat(buf, "-----END SIGNATURE-----\n", sizeof(buf));
        smartlist_add_strdup(elements, buf);
      } SMARTLIST_FOREACH_END(sig);
    } SMARTLIST_FOREACH_END(v);
  
    result = smartlist_join_strings(elements, "", 0, NULL);
    SMARTLIST_FOREACH(elements, char *, cp, tor_free(cp));
    smartlist_free(elements);
    if (!n_sigs)
      tor_free(result);
    return result;
  }
  
  /** Return a newly allocated string holding the detached-signatures document
   * corresponding to the signatures on <b>consensuses</b>, which must contain
   * exactly one FLAV_NS consensus, and no more than one consensus for each
   * other flavor. */
  STATIC char *
  networkstatus_get_detached_signatures(smartlist_t *consensuses)
  {
    smartlist_t *elements;
    char *result = NULL, *sigs = NULL;
    networkstatus_t *consensus_ns = NULL;
    tor_assert(consensuses);
  
    SMARTLIST_FOREACH(consensuses, networkstatus_t *, ns, {
        tor_assert(ns);
        tor_assert(ns->type == NS_TYPE_CONSENSUS);
        if (ns && ns->flavor == FLAV_NS)
          consensus_ns = ns;
    });
    if (!consensus_ns) {
      log_warn(LD_BUG, "No NS consensus given.");
      return NULL;
    }
  
    elements = smartlist_new();
  
    {
      char va_buf[ISO_TIME_LEN+1], fu_buf[ISO_TIME_LEN+1],
        vu_buf[ISO_TIME_LEN+1];
      char d[HEX_DIGEST_LEN+1];
  
      base16_encode(d, sizeof(d),
                    consensus_ns->digests.d[DIGEST_SHA1], DIGEST_LEN);
      format_iso_time(va_buf, consensus_ns->valid_after);
      format_iso_time(fu_buf, consensus_ns->fresh_until);
      format_iso_time(vu_buf, consensus_ns->valid_until);
  
      smartlist_add_asprintf(elements,
                   "consensus-digest %s\n"
                   "valid-after %s\n"
                   "fresh-until %s\n"
                   "valid-until %s\n", d, va_buf, fu_buf, vu_buf);
    }
  
    /* Get all the digests for the non-FLAV_NS consensuses */
    SMARTLIST_FOREACH_BEGIN(consensuses, networkstatus_t *, ns) {
      const char *flavor_name = networkstatus_get_flavor_name(ns->flavor);
      int alg;
      if (ns->flavor == FLAV_NS)
        continue;
  
      /* start with SHA256; we don't include SHA1 for anything but the basic
       * consensus. */
      for (alg = DIGEST_SHA256; alg < N_COMMON_DIGEST_ALGORITHMS; ++alg) {
        char d[HEX_DIGEST256_LEN+1];
        const char *alg_name =
          crypto_digest_algorithm_get_name(alg);
        if (fast_mem_is_zero(ns->digests.d[alg], DIGEST256_LEN))
          continue;
        base16_encode(d, sizeof(d), ns->digests.d[alg], DIGEST256_LEN);
        smartlist_add_asprintf(elements, "additional-digest %s %s %s\n",
                     flavor_name, alg_name, d);
      }
    } SMARTLIST_FOREACH_END(ns);
  
    /* Now get all the sigs for non-FLAV_NS consensuses */
    SMARTLIST_FOREACH_BEGIN(consensuses, networkstatus_t *, ns) {
      char *sigs_on_this_consensus;
      if (ns->flavor == FLAV_NS)
        continue;
      sigs_on_this_consensus = networkstatus_format_signatures(ns, 1);
      if (!sigs_on_this_consensus) {
        log_warn(LD_DIR, "Couldn't format signatures");
        goto err;
      }
      smartlist_add(elements, sigs_on_this_consensus);
    } SMARTLIST_FOREACH_END(ns);
  
    /* Now add the FLAV_NS consensus signatrures. */
    sigs = networkstatus_format_signatures(consensus_ns, 1);
    if (!sigs)
      goto err;
    smartlist_add(elements, sigs);
  
    result = smartlist_join_strings(elements, "", 0, NULL);
   err:
    SMARTLIST_FOREACH(elements, char *, cp, tor_free(cp));
    smartlist_free(elements);
    return result;
  }
  
  /** Return a newly allocated string holding a detached-signatures document for
   * all of the in-progress consensuses in the <b>n_flavors</b>-element array at
   * <b>pending</b>. */
  static char *
  get_detached_signatures_from_pending_consensuses(pending_consensus_t *pending,
                                                   int n_flavors)
  {
    int flav;
    char *signatures;
    smartlist_t *c = smartlist_new();
    for (flav = 0; flav < n_flavors; ++flav) {
      if (pending[flav].consensus)
        smartlist_add(c, pending[flav].consensus);
    }
    signatures = networkstatus_get_detached_signatures(c);
    smartlist_free(c);
    return signatures;
  }
  
  /**
   * Entry point: Take whatever voting actions are pending as of <b>now</b>.
   *
   * Return the time at which the next action should be taken.
   */
  time_t
  dirvote_act(const or_options_t *options, time_t now)
  {
    if (!authdir_mode_v3(options))
      return TIME_MAX;
    tor_assert_nonfatal(voting_schedule.voting_starts);
    /* If we haven't initialized this object through this codeflow, we need to
     * recalculate the timings to match our vote. The reason to do that is if we
     * have a voting schedule initialized 1 minute ago, the voting timings might
     * not be aligned to what we should expect with "now". This is especially
     * true for TestingTorNetwork using smaller timings.  */
    if (voting_schedule.created_on_demand) {
      char *keys = list_v3_auth_ids();
      authority_cert_t *c = get_my_v3_authority_cert();
      log_notice(LD_DIR, "Scheduling voting.  Known authority IDs are %s. "
                 "Mine is %s.",
                 keys, hex_str(c->cache_info.identity_digest, DIGEST_LEN));
      tor_free(keys);
      voting_schedule_recalculate_timing(options, now);
    }
  
  #define IF_TIME_FOR_NEXT_ACTION(when_field, done_field) \
    if (! voting_schedule.done_field) {                   \
      if (voting_schedule.when_field > now) {             \
        return voting_schedule.when_field;                \
      } else {
  #define ENDIF \
      }           \
    }
  
    IF_TIME_FOR_NEXT_ACTION(voting_starts, have_voted) {
      log_notice(LD_DIR, "Time to vote.");
      dirvote_perform_vote();
      voting_schedule.have_voted = 1;
    } ENDIF
    IF_TIME_FOR_NEXT_ACTION(fetch_missing_votes, have_fetched_missing_votes) {
      log_notice(LD_DIR, "Time to fetch any votes that we're missing.");
      dirvote_fetch_missing_votes();
      voting_schedule.have_fetched_missing_votes = 1;
    } ENDIF
    IF_TIME_FOR_NEXT_ACTION(voting_ends, have_built_consensus) {
      log_notice(LD_DIR, "Time to compute a consensus.");
      dirvote_compute_consensuses();
      /* XXXX We will want to try again later if we haven't got enough
       * votes yet.  Implement this if it turns out to ever happen. */
      voting_schedule.have_built_consensus = 1;
    } ENDIF
    IF_TIME_FOR_NEXT_ACTION(fetch_missing_signatures,
                            have_fetched_missing_signatures) {
      log_notice(LD_DIR, "Time to fetch any signatures that we're missing.");
      dirvote_fetch_missing_signatures();
      voting_schedule.have_fetched_missing_signatures = 1;
    } ENDIF
    IF_TIME_FOR_NEXT_ACTION(interval_starts,
                            have_published_consensus) {
      log_notice(LD_DIR, "Time to publish the consensus and discard old votes");
      dirvote_publish_consensus();
      dirvote_clear_votes(0);
      voting_schedule.have_published_consensus = 1;
      /* Update our shared random state with the consensus just published. */
      sr_act_post_consensus(
                  networkstatus_get_latest_consensus_by_flavor(FLAV_NS));
      /* XXXX We will want to try again later if we haven't got enough
       * signatures yet.  Implement this if it turns out to ever happen. */
      voting_schedule_recalculate_timing(options, now);
      return voting_schedule.voting_starts;
    } ENDIF
  
    tor_assert_nonfatal_unreached();
    return now + 1;
  
  #undef ENDIF
  #undef IF_TIME_FOR_NEXT_ACTION
  }
  
  /** A vote networkstatus_t and its unparsed body: held around so we can
   * use it to generate a consensus (at voting_ends) and so we can serve it to
   * other authorities that might want it. */
  typedef struct pending_vote_t {
    cached_dir_t *vote_body;
    networkstatus_t *vote;
  } pending_vote_t;
  
  /** List of pending_vote_t for the current vote.  Before we've used them to
   * build a consensus, the votes go here. */
  static smartlist_t *pending_vote_list = NULL;
  /** List of pending_vote_t for the previous vote.  After we've used them to
   * build a consensus, the votes go here for the next period. */
  static smartlist_t *previous_vote_list = NULL;
  
  /* DOCDOC pending_consensuses */
  static pending_consensus_t pending_consensuses[N_CONSENSUS_FLAVORS];
  
  /** The detached signatures for the consensus that we're currently
   * building. */
  static char *pending_consensus_signatures = NULL;
  
  /** List of ns_detached_signatures_t: hold signatures that get posted to us
   * before we have generated the consensus on our own. */
  static smartlist_t *pending_consensus_signature_list = NULL;
  
  /** Generate a networkstatus vote and post it to all the v3 authorities.
   * (V3 Authority only) */
  static int
  dirvote_perform_vote(void)
  {
    crypto_pk_t *key = get_my_v3_authority_signing_key();
    authority_cert_t *cert = get_my_v3_authority_cert();
    networkstatus_t *ns;
    char *contents;
    pending_vote_t *pending_vote;
    time_t now = time(NULL);
  
    int status;
    const char *msg = "";
  
    if (!cert || !key) {
      log_warn(LD_NET, "Didn't find key/certificate to generate v3 vote");
      return -1;
    } else if (cert->expires < now) {
      log_warn(LD_NET, "Can't generate v3 vote with expired certificate");
      return -1;
    }
    if (!(ns = dirserv_generate_networkstatus_vote_obj(key, cert)))
      return -1;
  
    contents = format_networkstatus_vote(key, ns);
    networkstatus_vote_free(ns);
    if (!contents)
      return -1;
  
    pending_vote = dirvote_add_vote(contents, &msg, &status);
    tor_free(contents);
    if (!pending_vote) {
      log_warn(LD_DIR, "Couldn't store my own vote! (I told myself, '%s'.)",
               msg);
      return -1;
    }
  
    directory_post_to_dirservers(DIR_PURPOSE_UPLOAD_VOTE,
                                 ROUTER_PURPOSE_GENERAL,
                                 V3_DIRINFO,
                                 pending_vote->vote_body->dir,
                                 pending_vote->vote_body->dir_len, 0);
    log_notice(LD_DIR, "Vote posted.");
    return 0;
  }
  
  /** Send an HTTP request to every other v3 authority, for the votes of every
   * authority for which we haven't received a vote yet in this period. (V3
   * authority only) */
  static void
  dirvote_fetch_missing_votes(void)
  {
    smartlist_t *missing_fps = smartlist_new();
    char *resource;
  
    SMARTLIST_FOREACH_BEGIN(router_get_trusted_dir_servers(),
                            dir_server_t *, ds) {
        if (!(ds->type & V3_DIRINFO))
          continue;
        if (!dirvote_get_vote(ds->v3_identity_digest,
                              DGV_BY_ID|DGV_INCLUDE_PENDING)) {
          char *cp = tor_malloc(HEX_DIGEST_LEN+1);
          base16_encode(cp, HEX_DIGEST_LEN+1, ds->v3_identity_digest,
                        DIGEST_LEN);
          smartlist_add(missing_fps, cp);
        }
    } SMARTLIST_FOREACH_END(ds);
  
    if (!smartlist_len(missing_fps)) {
      smartlist_free(missing_fps);
      return;
    }
    {
      char *tmp = smartlist_join_strings(missing_fps, " ", 0, NULL);
      log_notice(LOG_NOTICE, "We're missing votes from %d authorities (%s). "
                 "Asking every other authority for a copy.",
                 smartlist_len(missing_fps), tmp);
      tor_free(tmp);
    }
    resource = smartlist_join_strings(missing_fps, "+", 0, NULL);
    directory_get_from_all_authorities(DIR_PURPOSE_FETCH_STATUS_VOTE,
                                       0, resource);
    tor_free(resource);
    SMARTLIST_FOREACH(missing_fps, char *, cp, tor_free(cp));
    smartlist_free(missing_fps);
  }
  
  /** Send a request to every other authority for its detached signatures,
   * unless we have signatures from all other v3 authorities already. */
  static void
  dirvote_fetch_missing_signatures(void)
  {
    int need_any = 0;
    int i;
    for (i=0; i < N_CONSENSUS_FLAVORS; ++i) {
      networkstatus_t *consensus = pending_consensuses[i].consensus;
      if (!consensus ||
          networkstatus_check_consensus_signature(consensus, -1) == 1) {
        /* We have no consensus, or we have one that's signed by everybody. */
        continue;
      }
      need_any = 1;
    }
    if (!need_any)
      return;
  
    directory_get_from_all_authorities(DIR_PURPOSE_FETCH_DETACHED_SIGNATURES,
                                       0, NULL);
  }
  
  /** Release all storage held by pending consensuses (those waiting for
   * signatures). */
  static void
  dirvote_clear_pending_consensuses(void)
  {
    int i;
    for (i = 0; i < N_CONSENSUS_FLAVORS; ++i) {
      pending_consensus_t *pc = &pending_consensuses[i];
      tor_free(pc->body);
  
      networkstatus_vote_free(pc->consensus);
      pc->consensus = NULL;
    }
  }
  
  /** Drop all currently pending votes, consensus, and detached signatures. */
  static void
  dirvote_clear_votes(int all_votes)
  {
    if (!previous_vote_list)
      previous_vote_list = smartlist_new();
    if (!pending_vote_list)
      pending_vote_list = smartlist_new();
  
    /* All "previous" votes are now junk. */
    SMARTLIST_FOREACH(previous_vote_list, pending_vote_t *, v, {
        cached_dir_decref(v->vote_body);
        v->vote_body = NULL;
        networkstatus_vote_free(v->vote);
        tor_free(v);
      });
    smartlist_clear(previous_vote_list);
  
    if (all_votes) {
      /* If we're dumping all the votes, we delete the pending ones. */
      SMARTLIST_FOREACH(pending_vote_list, pending_vote_t *, v, {
          cached_dir_decref(v->vote_body);
          v->vote_body = NULL;
          networkstatus_vote_free(v->vote);
          tor_free(v);
        });
    } else {
      /* Otherwise, we move them into "previous". */
      smartlist_add_all(previous_vote_list, pending_vote_list);
    }
    smartlist_clear(pending_vote_list);
  
    if (pending_consensus_signature_list) {
      SMARTLIST_FOREACH(pending_consensus_signature_list, char *, cp,
                        tor_free(cp));
      smartlist_clear(pending_consensus_signature_list);
    }
    tor_free(pending_consensus_signatures);
    dirvote_clear_pending_consensuses();
  }
  
  /** Return a newly allocated string containing the hex-encoded v3 authority
      identity digest of every recognized v3 authority. */
  static char *
  list_v3_auth_ids(void)
  {
    smartlist_t *known_v3_keys = smartlist_new();
    char *keys;
    SMARTLIST_FOREACH(router_get_trusted_dir_servers(),
                      dir_server_t *, ds,
      if ((ds->type & V3_DIRINFO) &&
          !tor_digest_is_zero(ds->v3_identity_digest))
        smartlist_add(known_v3_keys,
                      tor_strdup(hex_str(ds->v3_identity_digest, DIGEST_LEN))));
    keys = smartlist_join_strings(known_v3_keys, ", ", 0, NULL);
    SMARTLIST_FOREACH(known_v3_keys, char *, cp, tor_free(cp));
    smartlist_free(known_v3_keys);
    return keys;
  }
  
  /** Called when we have received a networkstatus vote in <b>vote_body</b>.
   * Parse and validate it, and on success store it as a pending vote (which we
   * then return).  Return NULL on failure.  Sets *<b>msg_out</b> and
   * *<b>status_out</b> to an HTTP response and status code.  (V3 authority
   * only) */
  pending_vote_t *
  dirvote_add_vote(const char *vote_body, const char **msg_out, int *status_out)
  {
    networkstatus_t *vote;
    networkstatus_voter_info_t *vi;
    dir_server_t *ds;
    pending_vote_t *pending_vote = NULL;
    const char *end_of_vote = NULL;
    int any_failed = 0;
    tor_assert(vote_body);
    tor_assert(msg_out);
    tor_assert(status_out);
  
    if (!pending_vote_list)
      pending_vote_list = smartlist_new();
    *status_out = 0;
    *msg_out = NULL;
  
   again:
    vote = networkstatus_parse_vote_from_string(vote_body, strlen(vote_body),
                                                &end_of_vote,
                                                NS_TYPE_VOTE);
    if (!end_of_vote)
      end_of_vote = vote_body + strlen(vote_body);
    if (!vote) {
      log_warn(LD_DIR, "Couldn't parse vote: length was %d",
               (int)strlen(vote_body));
      *msg_out = "Unable to parse vote";
      goto err;
    }
    tor_assert(smartlist_len(vote->voters) == 1);
    vi = get_voter(vote);
    {
      int any_sig_good = 0;
      SMARTLIST_FOREACH(vi->sigs, document_signature_t *, sig,
                        if (sig->good_signature)
                          any_sig_good = 1);
      tor_assert(any_sig_good);
    }
    ds = trusteddirserver_get_by_v3_auth_digest(vi->identity_digest);
    if (!ds) {
      char *keys = list_v3_auth_ids();
      log_warn(LD_DIR, "Got a vote from an authority (nickname %s, address %s) "
               "with authority key ID %s. "
               "This key ID is not recognized.  Known v3 key IDs are: %s",
               vi->nickname, vi->address,
               hex_str(vi->identity_digest, DIGEST_LEN), keys);
      tor_free(keys);
      *msg_out = "Vote not from a recognized v3 authority";
      goto err;
    }
    tor_assert(vote->cert);
    if (!authority_cert_get_by_digests(vote->cert->cache_info.identity_digest,
                                       vote->cert->signing_key_digest)) {
      /* Hey, it's a new cert! */
      trusted_dirs_load_certs_from_string(
                                 vote->cert->cache_info.signed_descriptor_body,
                                 TRUSTED_DIRS_CERTS_SRC_FROM_VOTE, 1 /*flush*/,
                                 NULL);
      if (!authority_cert_get_by_digests(vote->cert->cache_info.identity_digest,
                                         vote->cert->signing_key_digest)) {
        log_warn(LD_BUG, "We added a cert, but still couldn't find it.");
      }
    }
  
    /* Is it for the right period? */
    if (vote->valid_after != voting_schedule.interval_starts) {
      char tbuf1[ISO_TIME_LEN+1], tbuf2[ISO_TIME_LEN+1];
      format_iso_time(tbuf1, vote->valid_after);
      format_iso_time(tbuf2, voting_schedule.interval_starts);
      log_warn(LD_DIR, "Rejecting vote from %s with valid-after time of %s; "
               "we were expecting %s", vi->address, tbuf1, tbuf2);
      *msg_out = "Bad valid-after time";
      goto err;
    }
  
    /* Fetch any new router descriptors we just learned about */
    update_consensus_router_descriptor_downloads(time(NULL), 1, vote);
  
    /* Now see whether we already have a vote from this authority. */
    SMARTLIST_FOREACH_BEGIN(pending_vote_list, pending_vote_t *, v) {
        if (fast_memeq(v->vote->cert->cache_info.identity_digest,
                     vote->cert->cache_info.identity_digest,
                     DIGEST_LEN)) {
          networkstatus_voter_info_t *vi_old = get_voter(v->vote);
          if (fast_memeq(vi_old->vote_digest, vi->vote_digest, DIGEST_LEN)) {
            /* Ah, it's the same vote. Not a problem. */
            log_info(LD_DIR, "Discarding a vote we already have (from %s).",
                     vi->address);
            if (*status_out < 200)
              *status_out = 200;
            goto discard;
          } else if (v->vote->published < vote->published) {
            log_notice(LD_DIR, "Replacing an older pending vote from this "
                       "directory (%s)", vi->address);
            cached_dir_decref(v->vote_body);
            networkstatus_vote_free(v->vote);
            v->vote_body = new_cached_dir(tor_strndup(vote_body,
                                                      end_of_vote-vote_body),
                                          vote->published);
            v->vote = vote;
            if (end_of_vote &&
                !strcmpstart(end_of_vote, "network-status-version"))
              goto again;
  
            if (*status_out < 200)
              *status_out = 200;
            if (!*msg_out)
              *msg_out = "OK";
            return v;
          } else {
            *msg_out = "Already have a newer pending vote";
            goto err;
          }
        }
    } SMARTLIST_FOREACH_END(v);
  
    /* This a valid vote, update our shared random state. */
    sr_handle_received_commits(vote->sr_info.commits,
                               vote->cert->identity_key);
  
    pending_vote = tor_malloc_zero(sizeof(pending_vote_t));
    pending_vote->vote_body = new_cached_dir(tor_strndup(vote_body,
                                                         end_of_vote-vote_body),
                                             vote->published);
    pending_vote->vote = vote;
    smartlist_add(pending_vote_list, pending_vote);
  
    if (!strcmpstart(end_of_vote, "network-status-version ")) {
      vote_body = end_of_vote;
      goto again;
    }
  
    goto done;
  
   err:
    any_failed = 1;
    if (!*msg_out)
      *msg_out = "Error adding vote";
    if (*status_out < 400)
      *status_out = 400;
  
   discard:
    networkstatus_vote_free(vote);
  
    if (end_of_vote && !strcmpstart(end_of_vote, "network-status-version ")) {
      vote_body = end_of_vote;
      goto again;
    }
  
   done:
  
    if (*status_out < 200)
      *status_out = 200;
    if (!*msg_out) {
      if (!any_failed && !pending_vote) {
        *msg_out = "Duplicate discarded";
      } else {
        *msg_out = "ok";
      }
    }
  
    return any_failed ? NULL : pending_vote;
  }
  
  /* Write the votes in <b>pending_vote_list</b> to disk. */
  static void
  write_v3_votes_to_disk(const smartlist_t *pending_votes)
  {
    smartlist_t *votestrings = smartlist_new();
    char *votefile = NULL;
  
    SMARTLIST_FOREACH(pending_votes, pending_vote_t *, v,
      {
        sized_chunk_t *c = tor_malloc(sizeof(sized_chunk_t));
        c->bytes = v->vote_body->dir;
        c->len = v->vote_body->dir_len;
        smartlist_add(votestrings, c); /* collect strings to write to disk */
      });
  
    votefile = get_datadir_fname("v3-status-votes");
    write_chunks_to_file(votefile, votestrings, 0, 0);
    log_debug(LD_DIR, "Wrote votes to disk (%s)!", votefile);
  
    tor_free(votefile);
    SMARTLIST_FOREACH(votestrings, sized_chunk_t *, c, tor_free(c));
    smartlist_free(votestrings);
  }
  
  /** Try to compute a v3 networkstatus consensus from the currently pending
   * votes.  Return 0 on success, -1 on failure.  Store the consensus in
   * pending_consensus: it won't be ready to be published until we have
   * everybody else's signatures collected too. (V3 Authority only) */
  static int
  dirvote_compute_consensuses(void)
  {
    /* Have we got enough votes to try? */
    int n_votes, n_voters, n_vote_running = 0;
    smartlist_t *votes = NULL;
    char *consensus_body = NULL, *signatures = NULL;
    networkstatus_t *consensus = NULL;
    authority_cert_t *my_cert;
    pending_consensus_t pending[N_CONSENSUS_FLAVORS];
    int flav;
  
    memset(pending, 0, sizeof(pending));
  
    if (!pending_vote_list)
      pending_vote_list = smartlist_new();
  
    /* Write votes to disk */
    write_v3_votes_to_disk(pending_vote_list);
  
    /* Setup votes smartlist */
    votes = smartlist_new();
    SMARTLIST_FOREACH(pending_vote_list, pending_vote_t *, v,
      {
        smartlist_add(votes, v->vote); /* collect votes to compute consensus */
      });
  
    /* See if consensus managed to achieve majority */
    n_voters = get_n_authorities(V3_DIRINFO);
    n_votes = smartlist_len(pending_vote_list);
    if (n_votes <= n_voters/2) {
      log_warn(LD_DIR, "We don't have enough votes to generate a consensus: "
               "%d of %d", n_votes, n_voters/2+1);
      goto err;
    }
    tor_assert(pending_vote_list);
    SMARTLIST_FOREACH(pending_vote_list, pending_vote_t *, v, {
      if (smartlist_contains_string(v->vote->known_flags, "Running"))
        n_vote_running++;
    });
    if (!n_vote_running) {
      /* See task 1066. */
      log_warn(LD_DIR, "Nobody has voted on the Running flag. Generating "
                       "and publishing a consensus without Running nodes "
                       "would make many clients stop working. Not "
                       "generating a consensus!");
      goto err;
    }
  
    if (!(my_cert = get_my_v3_authority_cert())) {
      log_warn(LD_DIR, "Can't generate consensus without a certificate.");
      goto err;
    }
  
    {
      char legacy_dbuf[DIGEST_LEN];
      crypto_pk_t *legacy_sign=NULL;
      char *legacy_id_digest = NULL;
      int n_generated = 0;
      if (get_options()->V3AuthUseLegacyKey) {
        authority_cert_t *cert = get_my_v3_legacy_cert();
        legacy_sign = get_my_v3_legacy_signing_key();
        if (cert) {
          if (crypto_pk_get_digest(cert->identity_key, legacy_dbuf)) {
            log_warn(LD_BUG,
                     "Unable to compute digest of legacy v3 identity key");
          } else {
            legacy_id_digest = legacy_dbuf;
          }
        }
      }
  
      for (flav = 0; flav < N_CONSENSUS_FLAVORS; ++flav) {
        const char *flavor_name = networkstatus_get_flavor_name(flav);
        consensus_body = networkstatus_compute_consensus(
          votes, n_voters,
          my_cert->identity_key,
          get_my_v3_authority_signing_key(), legacy_id_digest, legacy_sign,
          flav);
  
        if (!consensus_body) {
          log_warn(LD_DIR, "Couldn't generate a %s consensus at all!",
                   flavor_name);
          continue;
        }
        consensus = networkstatus_parse_vote_from_string(consensus_body,
                                                         strlen(consensus_body),
                                                         NULL,
                                                         NS_TYPE_CONSENSUS);
        if (!consensus) {
          log_warn(LD_DIR, "Couldn't parse %s consensus we generated!",
                   flavor_name);
          tor_free(consensus_body);
          continue;
        }
  
        /* 'Check' our own signature, to mark it valid. */
        networkstatus_check_consensus_signature(consensus, -1);
  
        pending[flav].body = consensus_body;
        pending[flav].consensus = consensus;
        n_generated++;
        consensus_body = NULL;
        consensus = NULL;
      }
      if (!n_generated) {
        log_warn(LD_DIR, "Couldn't generate any consensus flavors at all.");
        goto err;
      }
    }
  
    signatures = get_detached_signatures_from_pending_consensuses(
         pending, N_CONSENSUS_FLAVORS);
  
    if (!signatures) {
      log_warn(LD_DIR, "Couldn't extract signatures.");
      goto err;
    }
  
    dirvote_clear_pending_consensuses();
    memcpy(pending_consensuses, pending, sizeof(pending));
  
    tor_free(pending_consensus_signatures);
    pending_consensus_signatures = signatures;
  
    if (pending_consensus_signature_list) {
      int n_sigs = 0;
      /* we may have gotten signatures for this consensus before we built
       * it ourself.  Add them now. */
      SMARTLIST_FOREACH_BEGIN(pending_consensus_signature_list, char *, sig) {
          const char *msg = NULL;
          int r = dirvote_add_signatures_to_all_pending_consensuses(sig,
                                                       "pending", &msg);
          if (r >= 0)
            n_sigs += r;
          else
            log_warn(LD_DIR,
                     "Could not add queued signature to new consensus: %s",
                     msg);
          tor_free(sig);
      } SMARTLIST_FOREACH_END(sig);
      if (n_sigs)
        log_notice(LD_DIR, "Added %d pending signatures while building "
                   "consensus.", n_sigs);
      smartlist_clear(pending_consensus_signature_list);
    }
  
    log_notice(LD_DIR, "Consensus computed; uploading signature(s)");
  
    directory_post_to_dirservers(DIR_PURPOSE_UPLOAD_SIGNATURES,
                                 ROUTER_PURPOSE_GENERAL,
                                 V3_DIRINFO,
                                 pending_consensus_signatures,
                                 strlen(pending_consensus_signatures), 0);
    log_notice(LD_DIR, "Signature(s) posted.");
  
    smartlist_free(votes);
    return 0;
   err:
    smartlist_free(votes);
    tor_free(consensus_body);
    tor_free(signatures);
    networkstatus_vote_free(consensus);
  
    return -1;
  }
  
  /** Helper: we just got the <b>detached_signatures_body</b> sent to us as
   * signatures on the currently pending consensus.  Add them to <b>pc</b>
   * as appropriate.  Return the number of signatures added. (?) */
  static int
  dirvote_add_signatures_to_pending_consensus(
                         pending_consensus_t *pc,
                         ns_detached_signatures_t *sigs,
                         const char *source,
                         int severity,
                         const char **msg_out)
  {
    const char *flavor_name;
    int r = -1;
  
    /* Only call if we have a pending consensus right now. */
    tor_assert(pc->consensus);
    tor_assert(pc->body);
    tor_assert(pending_consensus_signatures);
  
    flavor_name = networkstatus_get_flavor_name(pc->consensus->flavor);
    *msg_out = NULL;
  
    {
      smartlist_t *sig_list = strmap_get(sigs->signatures, flavor_name);
      log_info(LD_DIR, "Have %d signatures for adding to %s consensus.",
               sig_list ? smartlist_len(sig_list) : 0, flavor_name);
    }
    r = networkstatus_add_detached_signatures(pc->consensus, sigs,
                                              source, severity, msg_out);
    if (r >= 0) {
      log_info(LD_DIR,"Added %d signatures to consensus.", r);
    } else {
      log_fn(LOG_PROTOCOL_WARN, LD_DIR,
             "Unable to add signatures to consensus: %s",
             *msg_out ? *msg_out : "(unknown)");
    }
  
    if (r >= 1) {
      char *new_signatures =
        networkstatus_format_signatures(pc->consensus, 0);
      char *dst, *dst_end;
      size_t new_consensus_len;
      if (!new_signatures) {
        *msg_out = "No signatures to add";
        goto err;
      }
      new_consensus_len =
        strlen(pc->body) + strlen(new_signatures) + 1;
      pc->body = tor_realloc(pc->body, new_consensus_len);
      dst_end = pc->body + new_consensus_len;
      dst = strstr(pc->body, "directory-signature ");
      tor_assert(dst);
      strlcpy(dst, new_signatures, dst_end-dst);
  
      /* We remove this block once it has failed to crash for a while.  But
       * unless it shows up in profiles, we're probably better leaving it in,
       * just in case we break detached signature processing at some point. */
      {
        networkstatus_t *v = networkstatus_parse_vote_from_string(
                                               pc->body, strlen(pc->body), NULL,
                                               NS_TYPE_CONSENSUS);
        tor_assert(v);
        networkstatus_vote_free(v);
      }
      *msg_out = "Signatures added";
      tor_free(new_signatures);
    } else if (r == 0) {
      *msg_out = "Signatures ignored";
    } else {
      goto err;
    }
  
    goto done;
   err:
    if (!*msg_out)
      *msg_out = "Unrecognized error while adding detached signatures.";
   done:
    return r;
  }
  
  static int
  dirvote_add_signatures_to_all_pending_consensuses(
                         const char *detached_signatures_body,
                         const char *source,
                         const char **msg_out)
  {
    int r=0, i, n_added = 0, errors = 0;
    ns_detached_signatures_t *sigs;
    tor_assert(detached_signatures_body);
    tor_assert(msg_out);
    tor_assert(pending_consensus_signatures);
  
    if (!(sigs = networkstatus_parse_detached_signatures(
                                 detached_signatures_body, NULL))) {
      *msg_out = "Couldn't parse detached signatures.";
      goto err;
    }
  
    for (i = 0; i < N_CONSENSUS_FLAVORS; ++i) {
      int res;
      int severity = i == FLAV_NS ? LOG_NOTICE : LOG_INFO;
      pending_consensus_t *pc = &pending_consensuses[i];
      if (!pc->consensus)
        continue;
      res = dirvote_add_signatures_to_pending_consensus(pc, sigs, source,
                                                        severity, msg_out);
      if (res < 0)
        errors++;
      else
        n_added += res;
    }
  
    if (errors && !n_added) {
      r = -1;
      goto err;
    }
  
    if (n_added && pending_consensuses[FLAV_NS].consensus) {
      char *new_detached =
        get_detached_signatures_from_pending_consensuses(
                        pending_consensuses, N_CONSENSUS_FLAVORS);
      if (new_detached) {
        tor_free(pending_consensus_signatures);
        pending_consensus_signatures = new_detached;
      }
    }
  
    r = n_added;
    goto done;
   err:
    if (!*msg_out)
      *msg_out = "Unrecognized error while adding detached signatures.";
   done:
    ns_detached_signatures_free(sigs);
    /* XXXX NM Check how return is used.  We can now have an error *and*
       signatures added. */
    return r;
  }
  
  /** Helper: we just got the <b>detached_signatures_body</b> sent to us as
   * signatures on the currently pending consensus.  Add them to the pending
   * consensus (if we have one); otherwise queue them until we have a
   * consensus.  Return negative on failure, nonnegative on success. */
  int
  dirvote_add_signatures(const char *detached_signatures_body,
                         const char *source,
                         const char **msg)
  {
    if (pending_consensuses[FLAV_NS].consensus) {
      log_notice(LD_DIR, "Got a signature from %s. "
                         "Adding it to the pending consensus.", source);
      return dirvote_add_signatures_to_all_pending_consensuses(
                                       detached_signatures_body, source, msg);
    } else {
      log_notice(LD_DIR, "Got a signature from %s. "
                         "Queuing it for the next consensus.", source);
      if (!pending_consensus_signature_list)
        pending_consensus_signature_list = smartlist_new();
      smartlist_add_strdup(pending_consensus_signature_list,
                    detached_signatures_body);
      *msg = "Signature queued";
      return 0;
    }
  }
  
  /** Replace the consensus that we're currently serving with the one that we've
   * been building. (V3 Authority only) */
  static int
  dirvote_publish_consensus(void)
  {
    int i;
  
    /* Now remember all the other consensuses as if we were a directory cache. */
    for (i = 0; i < N_CONSENSUS_FLAVORS; ++i) {
      pending_consensus_t *pending = &pending_consensuses[i];
      const char *name;
      name = networkstatus_get_flavor_name(i);
      tor_assert(name);
      if (!pending->consensus ||
        networkstatus_check_consensus_signature(pending->consensus, 1)<0) {
        log_warn(LD_DIR, "Not enough info to publish pending %s consensus",name);
        continue;
      }
  
      if (networkstatus_set_current_consensus(pending->body,
                                              strlen(pending->body),
                                              name, 0, NULL))
        log_warn(LD_DIR, "Error publishing %s consensus", name);
      else
        log_notice(LD_DIR, "Published %s consensus", name);
    }
  
    return 0;
  }
  
  /** Release all static storage held in dirvote.c */
  void
  dirvote_free_all(void)
  {
    dirvote_clear_votes(1);
    /* now empty as a result of dirvote_clear_votes(). */
    smartlist_free(pending_vote_list);
    pending_vote_list = NULL;
    smartlist_free(previous_vote_list);
    previous_vote_list = NULL;
  
    dirvote_clear_pending_consensuses();
    tor_free(pending_consensus_signatures);
    if (pending_consensus_signature_list) {
      /* now empty as a result of dirvote_clear_votes(). */
      smartlist_free(pending_consensus_signature_list);
      pending_consensus_signature_list = NULL;
    }
  }
  
  /* ====
   * Access to pending items.
   * ==== */
  
  /** Return the body of the consensus that we're currently trying to build. */
  MOCK_IMPL(const char *,
  dirvote_get_pending_consensus, (consensus_flavor_t flav))
  {
    tor_assert(((int)flav) >= 0 && (int)flav < N_CONSENSUS_FLAVORS);
    return pending_consensuses[flav].body;
  }
  
  /** Return the signatures that we know for the consensus that we're currently
   * trying to build. */
  MOCK_IMPL(const char *,
  dirvote_get_pending_detached_signatures, (void))
  {
    return pending_consensus_signatures;
  }
  
  /** Return a given vote specified by <b>fp</b>.  If <b>by_id</b>, return the
   * vote for the authority with the v3 authority identity key digest <b>fp</b>;
   * if <b>by_id</b> is false, return the vote whose digest is <b>fp</b>.  If
   * <b>fp</b> is NULL, return our own vote.  If <b>include_previous</b> is
   * false, do not consider any votes for a consensus that's already been built.
   * If <b>include_pending</b> is false, do not consider any votes for the
   * consensus that's in progress.  May return NULL if we have no vote for the
   * authority in question. */
  const cached_dir_t *
  dirvote_get_vote(const char *fp, int flags)
  {
    int by_id = flags & DGV_BY_ID;
    const int include_pending = flags & DGV_INCLUDE_PENDING;
    const int include_previous = flags & DGV_INCLUDE_PREVIOUS;
  
    if (!pending_vote_list && !previous_vote_list)
      return NULL;
    if (fp == NULL) {
      authority_cert_t *c = get_my_v3_authority_cert();
      if (c) {
        fp = c->cache_info.identity_digest;
        by_id = 1;
      } else
        return NULL;
    }
    if (by_id) {
      if (pending_vote_list && include_pending) {
        SMARTLIST_FOREACH(pending_vote_list, pending_vote_t *, pv,
          if (fast_memeq(get_voter(pv->vote)->identity_digest, fp, DIGEST_LEN))
            return pv->vote_body);
      }
      if (previous_vote_list && include_previous) {
        SMARTLIST_FOREACH(previous_vote_list, pending_vote_t *, pv,
          if (fast_memeq(get_voter(pv->vote)->identity_digest, fp, DIGEST_LEN))
            return pv->vote_body);
      }
    } else {
      if (pending_vote_list && include_pending) {
        SMARTLIST_FOREACH(pending_vote_list, pending_vote_t *, pv,
          if (fast_memeq(pv->vote->digests.d[DIGEST_SHA1], fp, DIGEST_LEN))
            return pv->vote_body);
      }
      if (previous_vote_list && include_previous) {
        SMARTLIST_FOREACH(previous_vote_list, pending_vote_t *, pv,
          if (fast_memeq(pv->vote->digests.d[DIGEST_SHA1], fp, DIGEST_LEN))
            return pv->vote_body);
      }
    }
    return NULL;
  }
  
  /** Construct and return a new microdescriptor from a routerinfo <b>ri</b>
   * according to <b>consensus_method</b>.
   **/
  STATIC microdesc_t *
  dirvote_create_microdescriptor(const routerinfo_t *ri, int consensus_method)
  {
    microdesc_t *result = NULL;
    char *key = NULL, *summary = NULL, *family = NULL;
    size_t keylen;
    smartlist_t *chunks = smartlist_new();
    char *output = NULL;
    crypto_pk_t *rsa_pubkey = router_get_rsa_onion_pkey(ri->onion_pkey,
                                                        ri->onion_pkey_len);
  
    if (crypto_pk_write_public_key_to_string(rsa_pubkey, &key, &keylen)<0)
      goto done;
    summary = policy_summarize(ri->exit_policy, AF_INET);
    if (ri->declared_family)
      family = smartlist_join_strings(ri->declared_family, " ", 0, NULL);
  
    smartlist_add_asprintf(chunks, "onion-key\n%s", key);
  
    if (ri->onion_curve25519_pkey) {
      char kbuf[128];
      base64_encode(kbuf, sizeof(kbuf),
                    (const char*)ri->onion_curve25519_pkey->public_key,
                    CURVE25519_PUBKEY_LEN, BASE64_ENCODE_MULTILINE);
      smartlist_add_asprintf(chunks, "ntor-onion-key %s", kbuf);
    }
  
    /* We originally put a lines in the micrdescriptors, but then we worked out
     * that we needed them in the microdesc consensus. See #20916. */
    if (consensus_method < MIN_METHOD_FOR_NO_A_LINES_IN_MICRODESC &&
        !tor_addr_is_null(&ri->ipv6_addr) && ri->ipv6_orport)
      smartlist_add_asprintf(chunks, "a %s\n",
                             fmt_addrport(&ri->ipv6_addr, ri->ipv6_orport));
  
    if (family) {
      if (consensus_method < MIN_METHOD_FOR_CANONICAL_FAMILIES_IN_MICRODESCS) {
        smartlist_add_asprintf(chunks, "family %s\n", family);
      } else {
        const uint8_t *id = (const uint8_t *)ri->cache_info.identity_digest;
        char *canonical_family = nodefamily_canonicalize(family, id, 0);
        smartlist_add_asprintf(chunks, "family %s\n", canonical_family);
        tor_free(canonical_family);
      }
    }
  
    if (summary && strcmp(summary, "reject 1-65535"))
      smartlist_add_asprintf(chunks, "p %s\n", summary);
  
    if (ri->ipv6_exit_policy) {
      /* XXXX+++ This doesn't match proposal 208, which says these should
       * be taken unchanged from the routerinfo.  That's bogosity, IMO:
       * the proposal should have said to do this instead.*/
      char *p6 = write_short_policy(ri->ipv6_exit_policy);
      if (p6 && strcmp(p6, "reject 1-65535"))
        smartlist_add_asprintf(chunks, "p6 %s\n", p6);
      tor_free(p6);
    }
  
    {
      char idbuf[ED25519_BASE64_LEN+1];
      const char *keytype;
      if (ri->cache_info.signing_key_cert &&
          ri->cache_info.signing_key_cert->signing_key_included) {
        keytype = "ed25519";
        ed25519_public_to_base64(idbuf,
                                 &ri->cache_info.signing_key_cert->signing_key);
      } else {
        keytype = "rsa1024";
        digest_to_base64(idbuf, ri->cache_info.identity_digest);
      }
      smartlist_add_asprintf(chunks, "id %s %s\n", keytype, idbuf);
    }
  
    output = smartlist_join_strings(chunks, "", 0, NULL);
  
    {
      smartlist_t *lst = microdescs_parse_from_string(output,
                                                      output+strlen(output), 0,
                                                      SAVED_NOWHERE, NULL);
      if (smartlist_len(lst) != 1) {
        log_warn(LD_DIR, "We generated a microdescriptor we couldn't parse.");
        SMARTLIST_FOREACH(lst, microdesc_t *, md, microdesc_free(md));
        smartlist_free(lst);
        goto done;
      }
      result = smartlist_get(lst, 0);
      smartlist_free(lst);
    }
  
   done:
    crypto_pk_free(rsa_pubkey);
    tor_free(output);
    tor_free(key);
    tor_free(summary);
    tor_free(family);
    if (chunks) {
      SMARTLIST_FOREACH(chunks, char *, cp, tor_free(cp));
      smartlist_free(chunks);
    }
    return result;
  }
  
  /** Format the appropriate vote line to describe the microdescriptor <b>md</b>
   * in a consensus vote document.  Write it into the <b>out_len</b>-byte buffer
   * in <b>out</b>.  Return -1 on failure and the number of characters written
   * on success. */
  static ssize_t
  dirvote_format_microdesc_vote_line(char *out_buf, size_t out_buf_len,
                                     const microdesc_t *md,
                                     int consensus_method_low,
                                     int consensus_method_high)
  {
    ssize_t ret = -1;
    char d64[BASE64_DIGEST256_LEN+1];
    char *microdesc_consensus_methods =
      make_consensus_method_list(consensus_method_low,
                                 consensus_method_high,
                                 ",");
    tor_assert(microdesc_consensus_methods);
  
    digest256_to_base64(d64, md->digest);
  
    if (tor_snprintf(out_buf, out_buf_len, "m %s sha256=%s\n",
                     microdesc_consensus_methods, d64)<0)
      goto out;
  
    ret = strlen(out_buf);
  
   out:
    tor_free(microdesc_consensus_methods);
    return ret;
  }
  
  /** Array of start and end of consensus methods used for supported
      microdescriptor formats. */
  static const struct consensus_method_range_t {
    int low;
    int high;
  } microdesc_consensus_methods[] = {
    {MIN_SUPPORTED_CONSENSUS_METHOD, MIN_METHOD_FOR_NO_A_LINES_IN_MICRODESC - 1},
    {MIN_METHOD_FOR_NO_A_LINES_IN_MICRODESC,
     MIN_METHOD_FOR_CANONICAL_FAMILIES_IN_MICRODESCS - 1},
    {MIN_METHOD_FOR_CANONICAL_FAMILIES_IN_MICRODESCS,
     MAX_SUPPORTED_CONSENSUS_METHOD},
    {-1, -1}
  };
  
  /** Helper type used when generating the microdescriptor lines in a directory
   * vote. */
  typedef struct microdesc_vote_line_t {
    int low;
    int high;
    microdesc_t *md;
    struct microdesc_vote_line_t *next;
  } microdesc_vote_line_t;
  
  /** Generate and return a linked list of all the lines that should appear to
   * describe a router's microdescriptor versions in a directory vote.
   * Add the generated microdescriptors to <b>microdescriptors_out</b>. */
  vote_microdesc_hash_t *
  dirvote_format_all_microdesc_vote_lines(const routerinfo_t *ri, time_t now,
                                          smartlist_t *microdescriptors_out)
  {
    const struct consensus_method_range_t *cmr;
    microdesc_vote_line_t *entries = NULL, *ep;
    vote_microdesc_hash_t *result = NULL;
  
    /* Generate the microdescriptors. */
    for (cmr = microdesc_consensus_methods;
         cmr->low != -1 && cmr->high != -1;
         cmr++) {
      microdesc_t *md = dirvote_create_microdescriptor(ri, cmr->low);
      if (md) {
        microdesc_vote_line_t *e =
          tor_malloc_zero(sizeof(microdesc_vote_line_t));
        e->md = md;
        e->low = cmr->low;
        e->high = cmr->high;
        e->next = entries;
        entries = e;
      }
    }
  
    /* Compress adjacent identical ones */
    for (ep = entries; ep; ep = ep->next) {
      while (ep->next &&
             fast_memeq(ep->md->digest, ep->next->md->digest, DIGEST256_LEN) &&
             ep->low == ep->next->high + 1) {
        microdesc_vote_line_t *next = ep->next;
        ep->low = next->low;
        microdesc_free(next->md);
        ep->next = next->next;
        tor_free(next);
      }
    }
  
    /* Format them into vote_microdesc_hash_t, and add to microdescriptors_out.*/
    while ((ep = entries)) {
      char buf[128];
      vote_microdesc_hash_t *h;
      if (dirvote_format_microdesc_vote_line(buf, sizeof(buf), ep->md,
                                             ep->low, ep->high) >= 0) {
        h = tor_malloc_zero(sizeof(vote_microdesc_hash_t));
        h->microdesc_hash_line = tor_strdup(buf);
        h->next = result;
        result = h;
        ep->md->last_listed = now;
        smartlist_add(microdescriptors_out, ep->md);
      }
      entries = ep->next;
      tor_free(ep);
    }
  
    return result;
  }
  
  /** Parse and extract all SR commits from <b>tokens</b> and place them in
   *  <b>ns</b>. */
  static void
  extract_shared_random_commits(networkstatus_t *ns, const smartlist_t *tokens)
  {
    smartlist_t *chunks = NULL;
  
    tor_assert(ns);
    tor_assert(tokens);
    /* Commits are only present in a vote. */
    tor_assert(ns->type == NS_TYPE_VOTE);
  
    ns->sr_info.commits = smartlist_new();
  
    smartlist_t *commits = find_all_by_keyword(tokens, K_COMMIT);
    /* It's normal that a vote might contain no commits even if it participates
     * in the SR protocol. Don't treat it as an error. */
    if (commits == NULL) {
      goto end;
    }
  
    /* Parse the commit. We do NO validation of number of arguments or ordering
     * for forward compatibility, it's the parse commit job to inform us if it's
     * supported or not. */
    chunks = smartlist_new();
    SMARTLIST_FOREACH_BEGIN(commits, directory_token_t *, tok) {
      /* Extract all arguments and put them in the chunks list. */
      for (int i = 0; i < tok->n_args; i++) {
        smartlist_add(chunks, tok->args[i]);
      }
      sr_commit_t *commit = sr_parse_commit(chunks);
      smartlist_clear(chunks);
      if (commit == NULL) {
        /* Get voter identity so we can warn that this dirauth vote contains
         * commit we can't parse. */
        networkstatus_voter_info_t *voter = smartlist_get(ns->voters, 0);
        tor_assert(voter);
        log_warn(LD_DIR, "SR: Unable to parse commit %s from vote of voter %s.",
                 escaped(tok->object_body),
                 hex_str(voter->identity_digest,
                         sizeof(voter->identity_digest)));
        /* Commitment couldn't be parsed. Continue onto the next commit because
         * this one could be unsupported for instance. */
        continue;
      }
      /* Add newly created commit object to the vote. */
      smartlist_add(ns->sr_info.commits, commit);
    } SMARTLIST_FOREACH_END(tok);
  
   end:
    smartlist_free(chunks);
    smartlist_free(commits);
  }
  
  /* Using the given directory tokens in tokens, parse the shared random commits
   * and put them in the given vote document ns.
   *
   * This also sets the SR participation flag if present in the vote. */
  void
  dirvote_parse_sr_commits(networkstatus_t *ns, const smartlist_t *tokens)
  {
    /* Does this authority participates in the SR protocol? */
    directory_token_t *tok = find_opt_by_keyword(tokens, K_SR_FLAG);
    if (tok) {
      ns->sr_info.participate = 1;
      /* Get the SR commitments and reveals from the vote. */
      extract_shared_random_commits(ns, tokens);
    }
  }
  
  /* For the given vote, free the shared random commits if any. */
  void
  dirvote_clear_commits(networkstatus_t *ns)
  {
    tor_assert(ns->type == NS_TYPE_VOTE);
  
    if (ns->sr_info.commits) {
      SMARTLIST_FOREACH(ns->sr_info.commits, sr_commit_t *, c,
                        sr_commit_free(c));
      smartlist_free(ns->sr_info.commits);
    }
  }
  
  /* The given url is the /tor/status-vote GET directory request. Populates the
   * items list with strings that we can compress on the fly and dir_items with
   * cached_dir_t objects that have a precompressed deflated version. */
  void
  dirvote_dirreq_get_status_vote(const char *url, smartlist_t *items,
                                 smartlist_t *dir_items)
  {
    int current;
  
    url += strlen("/tor/status-vote/");
    current = !strcmpstart(url, "current/");
    url = strchr(url, '/');
    tor_assert(url);
    ++url;
    if (!strcmp(url, "consensus")) {
      const char *item;
      tor_assert(!current); /* we handle current consensus specially above,
                             * since it wants to be spooled. */
      if ((item = dirvote_get_pending_consensus(FLAV_NS)))
        smartlist_add(items, (char*)item);
    } else if (!current && !strcmp(url, "consensus-signatures")) {
      /* XXXX the spec says that we should implement
       * current/consensus-signatures too.  It doesn't seem to be needed,
       * though. */
      const char *item;
      if ((item=dirvote_get_pending_detached_signatures()))
        smartlist_add(items, (char*)item);
    } else if (!strcmp(url, "authority")) {
      const cached_dir_t *d;
      int flags = DGV_BY_ID |
        (current ? DGV_INCLUDE_PREVIOUS : DGV_INCLUDE_PENDING);
      if ((d=dirvote_get_vote(NULL, flags)))
        smartlist_add(dir_items, (cached_dir_t*)d);
    } else {
      const cached_dir_t *d;
      smartlist_t *fps = smartlist_new();
      int flags;
      if (!strcmpstart(url, "d/")) {
        url += 2;
        flags = DGV_INCLUDE_PENDING | DGV_INCLUDE_PREVIOUS;
      } else {
        flags = DGV_BY_ID |
          (current ? DGV_INCLUDE_PREVIOUS : DGV_INCLUDE_PENDING);
      }
      dir_split_resource_into_fingerprints(url, fps, NULL,
                                           DSR_HEX|DSR_SORT_UNIQ);
      SMARTLIST_FOREACH(fps, char *, fp, {
                        if ((d = dirvote_get_vote(fp, flags)))
                        smartlist_add(dir_items, (cached_dir_t*)d);
                        tor_free(fp);
                        });
      smartlist_free(fps);
    }
  }
  
  /** Get the best estimate of a router's bandwidth for dirauth purposes,
   * preferring measured to advertised values if available. */
  static uint32_t
  dirserv_get_bandwidth_for_router_kb(const routerinfo_t *ri)
  {
    uint32_t bw_kb = 0;
    /*
     * Yeah, measured bandwidths in measured_bw_line_t are (implicitly
     * signed) longs and the ones router_get_advertised_bandwidth() returns
     * are uint32_t.
     */
    long mbw_kb = 0;
  
    if (ri) {
      /*
       * * First try to see if we have a measured bandwidth; don't bother with
       * as_of_out here, on the theory that a stale measured bandwidth is still
       * better to trust than an advertised one.
       */
      if (dirserv_query_measured_bw_cache_kb(ri->cache_info.identity_digest,
                                             &mbw_kb, NULL)) {
        /* Got one! */
        bw_kb = (uint32_t)mbw_kb;
      } else {
        /* If not, fall back to advertised */
        bw_kb = router_get_advertised_bandwidth(ri) / 1000;
      }
    }
  
    return bw_kb;
  }
  
  /** Helper for sorting: compares two routerinfos first by address, and then by
   * descending order of "usefulness".  (An authority is more useful than a
   * non-authority; a running router is more useful than a non-running router;
   * and a router with more bandwidth is more useful than one with less.)
   **/
  static int
  compare_routerinfo_by_ip_and_bw_(const void **a, const void **b)
  {
    routerinfo_t *first = *(routerinfo_t **)a, *second = *(routerinfo_t **)b;
    int first_is_auth, second_is_auth;
    uint32_t bw_kb_first, bw_kb_second;
    const node_t *node_first, *node_second;
    int first_is_running, second_is_running;
  
    /* we return -1 if first should appear before second... that is,
     * if first is a better router. */
    if (first->addr < second->addr)
      return -1;
    else if (first->addr > second->addr)
      return 1;
  
    /* Potentially, this next bit could cause k n lg n memeq calls.  But in
     * reality, we will almost never get here, since addresses will usually be
     * different. */
  
    first_is_auth =
      router_digest_is_trusted_dir(first->cache_info.identity_digest);
    second_is_auth =
      router_digest_is_trusted_dir(second->cache_info.identity_digest);
  
    if (first_is_auth && !second_is_auth)
      return -1;
    else if (!first_is_auth && second_is_auth)
      return 1;
  
    node_first = node_get_by_id(first->cache_info.identity_digest);
    node_second = node_get_by_id(second->cache_info.identity_digest);
    first_is_running = node_first && node_first->is_running;
    second_is_running = node_second && node_second->is_running;
  
    if (first_is_running && !second_is_running)
      return -1;
    else if (!first_is_running && second_is_running)
      return 1;
  
    bw_kb_first = dirserv_get_bandwidth_for_router_kb(first);
    bw_kb_second = dirserv_get_bandwidth_for_router_kb(second);
  
    if (bw_kb_first > bw_kb_second)
      return -1;
    else if (bw_kb_first < bw_kb_second)
      return 1;
  
    /* They're equal! Compare by identity digest, so there's a
     * deterministic order and we avoid flapping. */
    return fast_memcmp(first->cache_info.identity_digest,
                       second->cache_info.identity_digest,
                       DIGEST_LEN);
  }
  
  /** Given a list of routerinfo_t in <b>routers</b>, return a new digestmap_t
   * whose keys are the identity digests of those routers that we're going to
   * exclude for Sybil-like appearance. */
  static digestmap_t *
  get_possible_sybil_list(const smartlist_t *routers)
  {
    const or_options_t *options = get_options();
    digestmap_t *omit_as_sybil;
    smartlist_t *routers_by_ip = smartlist_new();
    uint32_t last_addr;
    int addr_count;
    /* Allow at most this number of Tor servers on a single IP address, ... */
    int max_with_same_addr = options->AuthDirMaxServersPerAddr;
    if (max_with_same_addr <= 0)
      max_with_same_addr = INT_MAX;
  
    smartlist_add_all(routers_by_ip, routers);
    smartlist_sort(routers_by_ip, compare_routerinfo_by_ip_and_bw_);
    omit_as_sybil = digestmap_new();
  
    last_addr = 0;
    addr_count = 0;
    SMARTLIST_FOREACH_BEGIN(routers_by_ip, routerinfo_t *, ri) {
      if (last_addr != ri->addr) {
        last_addr = ri->addr;
        addr_count = 1;
      } else if (++addr_count > max_with_same_addr) {
        digestmap_set(omit_as_sybil, ri->cache_info.identity_digest, ri);
      }
    } SMARTLIST_FOREACH_END(ri);
  
    smartlist_free(routers_by_ip);
    return omit_as_sybil;
  }
  
  /** Given a platform string as in a routerinfo_t (possibly null), return a
   * newly allocated version string for a networkstatus document, or NULL if the
   * platform doesn't give a Tor version. */
  static char *
  version_from_platform(const char *platform)
  {
    if (platform && !strcmpstart(platform, "Tor ")) {
      const char *eos = find_whitespace(platform+4);
      if (eos && !strcmpstart(eos, " (r")) {
        /* XXXX Unify this logic with the other version extraction
         * logic in routerparse.c. */
        eos = find_whitespace(eos+1);
      }
      if (eos) {
        return tor_strndup(platform, eos-platform);
      }
    }
    return NULL;
  }
  
  /** Given a (possibly empty) list of config_line_t, each line of which contains
   * a list of comma-separated version numbers surrounded by optional space,
   * allocate and return a new string containing the version numbers, in order,
   * separated by commas.  Used to generate Recommended(Client|Server)?Versions
   */
  char *
  format_recommended_version_list(const config_line_t *ln, int warn)
  {
    smartlist_t *versions;
    char *result;
    versions = smartlist_new();
    for ( ; ln; ln = ln->next) {
      smartlist_split_string(versions, ln->value, ",",
                             SPLIT_SKIP_SPACE|SPLIT_IGNORE_BLANK, 0);
    }
  
    /* Handle the case where a dirauth operator has accidentally made some
     * versions space-separated instead of comma-separated. */
    smartlist_t *more_versions = smartlist_new();
    SMARTLIST_FOREACH_BEGIN(versions, char *, v) {
      if (strchr(v, ' ')) {
        if (warn)
          log_warn(LD_DIRSERV, "Unexpected space in versions list member %s. "
                   "(These are supposed to be comma-separated; I'll pretend you "
                   "used commas instead.)", escaped(v));
        SMARTLIST_DEL_CURRENT(versions, v);
        smartlist_split_string(more_versions, v, NULL,
                               SPLIT_SKIP_SPACE|SPLIT_IGNORE_BLANK, 0);
        tor_free(v);
      }
    } SMARTLIST_FOREACH_END(v);
    smartlist_add_all(versions, more_versions);
    smartlist_free(more_versions);
  
    /* Check to make sure everything looks like a version. */
    if (warn) {
      SMARTLIST_FOREACH_BEGIN(versions, const char *, v) {
        tor_version_t ver;
        if (tor_version_parse(v, &ver) < 0) {
          log_warn(LD_DIRSERV, "Recommended version %s does not look valid. "
                   " (I'll include it anyway, since you told me to.)",
                   escaped(v));
        }
      } SMARTLIST_FOREACH_END(v);
    }
  
    sort_version_list(versions, 1);
    result = smartlist_join_strings(versions,",",0,NULL);
    SMARTLIST_FOREACH(versions,char *,s,tor_free(s));
    smartlist_free(versions);
    return result;
  }
  
  /** If there are entries in <b>routers</b> with exactly the same ed25519 keys,
   * remove the older one.  If they are exactly the same age, remove the one
   * with the greater descriptor digest. May alter the order of the list. */
  static void
  routers_make_ed_keys_unique(smartlist_t *routers)
  {
    routerinfo_t *ri2;
    digest256map_t *by_ed_key = digest256map_new();
  
    SMARTLIST_FOREACH_BEGIN(routers, routerinfo_t *, ri) {
      ri->omit_from_vote = 0;
      if (ri->cache_info.signing_key_cert == NULL)
        continue; /* No ed key */
      const uint8_t *pk = ri->cache_info.signing_key_cert->signing_key.pubkey;
      if ((ri2 = digest256map_get(by_ed_key, pk))) {
        /* Duplicate; must omit one.  Set the omit_from_vote flag in whichever
         * one has the earlier published_on. */
        const time_t ri_pub = ri->cache_info.published_on;
        const time_t ri2_pub = ri2->cache_info.published_on;
        if (ri2_pub < ri_pub ||
            (ri2_pub == ri_pub &&
             fast_memcmp(ri->cache_info.signed_descriptor_digest,
                       ri2->cache_info.signed_descriptor_digest,DIGEST_LEN)<0)) {
          digest256map_set(by_ed_key, pk, ri);
          ri2->omit_from_vote = 1;
        } else {
          ri->omit_from_vote = 1;
        }
      } else {
        /* Add to map */
        digest256map_set(by_ed_key, pk, ri);
      }
    } SMARTLIST_FOREACH_END(ri);
  
    digest256map_free(by_ed_key, NULL);
  
    /* Now remove every router where the omit_from_vote flag got set. */
    SMARTLIST_FOREACH_BEGIN(routers, const routerinfo_t *, ri) {
      if (ri->omit_from_vote) {
        SMARTLIST_DEL_CURRENT(routers, ri);
      }
    } SMARTLIST_FOREACH_END(ri);
  }
  
  /** Routerstatus <b>rs</b> is part of a group of routers that are on
   * too narrow an IP-space. Clear out its flags since we don't want it be used
   * because of its Sybil-like appearance.
   *
   * Leave its BadExit flag alone though, since if we think it's a bad exit,
   * we want to vote that way in case all the other authorities are voting
   * Running and Exit.
   */
  static void
  clear_status_flags_on_sybil(routerstatus_t *rs)
  {
    rs->is_authority = rs->is_exit = rs->is_stable = rs->is_fast =
      rs->is_flagged_running = rs->is_named = rs->is_valid =
      rs->is_hs_dir = rs->is_v2_dir = rs->is_possible_guard = 0;
    /* FFFF we might want some mechanism to check later on if we
     * missed zeroing any flags: it's easy to add a new flag but
     * forget to add it to this clause. */
  }
  
  /** Space-separated list of all the flags that we will always vote on. */
  const char DIRVOTE_UNIVERSAL_FLAGS[] =
    "Authority "
    "Exit "
    "Fast "
    "Guard "
    "HSDir "
    "Stable "
    "StaleDesc "
    "V2Dir "
    "Valid";
  /** Space-separated list of all flags that we may or may not vote on,
   * depending on our configuration. */
  const char DIRVOTE_OPTIONAL_FLAGS[] =
    "BadExit "
    "Running";
  
  /** Return a new networkstatus_t* containing our current opinion. (For v3
   * authorities) */
  networkstatus_t *
  dirserv_generate_networkstatus_vote_obj(crypto_pk_t *private_key,
                                          authority_cert_t *cert)
  {
    const or_options_t *options = get_options();
    networkstatus_t *v3_out = NULL;
    uint32_t addr;
    char *hostname = NULL, *client_versions = NULL, *server_versions = NULL;
    const char *contact;
    smartlist_t *routers, *routerstatuses;
    char identity_digest[DIGEST_LEN];
    char signing_key_digest[DIGEST_LEN];
    int listbadexits = options->AuthDirListBadExits;
    routerlist_t *rl = router_get_routerlist();
    time_t now = time(NULL);
    time_t cutoff = now - ROUTER_MAX_AGE_TO_PUBLISH;
    networkstatus_voter_info_t *voter = NULL;
    vote_timing_t timing;
    digestmap_t *omit_as_sybil = NULL;
    const int vote_on_reachability = running_long_enough_to_decide_unreachable();
    smartlist_t *microdescriptors = NULL;
    smartlist_t *bw_file_headers = NULL;
    uint8_t bw_file_digest256[DIGEST256_LEN] = {0};
  
    tor_assert(private_key);
    tor_assert(cert);
  
    if (crypto_pk_get_digest(private_key, signing_key_digest)<0) {
      log_err(LD_BUG, "Error computing signing key digest");
      return NULL;
    }
    if (crypto_pk_get_digest(cert->identity_key, identity_digest)<0) {
      log_err(LD_BUG, "Error computing identity key digest");
      return NULL;
    }
    if (resolve_my_address(LOG_WARN, options, &addr, NULL, &hostname)<0) {
      log_warn(LD_NET, "Couldn't resolve my hostname");
      return NULL;
    }
    if (!hostname || !strchr(hostname, '.')) {
      tor_free(hostname);
      hostname = tor_dup_ip(addr);
    }
  
    if (options->VersioningAuthoritativeDir) {
      client_versions =
        format_recommended_version_list(options->RecommendedClientVersions, 0);
      server_versions =
        format_recommended_version_list(options->RecommendedServerVersions, 0);
    }
  
    contact = get_options()->ContactInfo;
    if (!contact)
      contact = "(none)";
  
    /*
     * Do this so dirserv_compute_performance_thresholds() and
     * set_routerstatus_from_routerinfo() see up-to-date bandwidth info.
     */
    if (options->V3BandwidthsFile) {
      dirserv_read_measured_bandwidths(options->V3BandwidthsFile, NULL, NULL,
                                       NULL);
    } else {
      /*
       * No bandwidths file; clear the measured bandwidth cache in case we had
       * one last time around.
       */
      if (dirserv_get_measured_bw_cache_size() > 0) {
        dirserv_clear_measured_bw_cache();
      }
    }
  
    /* precompute this part, since we need it to decide what "stable"
     * means. */
    SMARTLIST_FOREACH(rl->routers, routerinfo_t *, ri, {
                      dirserv_set_router_is_running(ri, now);
                      });
  
    routers = smartlist_new();
    smartlist_add_all(routers, rl->routers);
    routers_make_ed_keys_unique(routers);
    /* After this point, don't use rl->routers; use 'routers' instead. */
    routers_sort_by_identity(routers);
    omit_as_sybil = get_possible_sybil_list(routers);
  
    DIGESTMAP_FOREACH(omit_as_sybil, sybil_id, void *, ignore) {
      (void) ignore;
      rep_hist_make_router_pessimal(sybil_id, now);
    } DIGESTMAP_FOREACH_END;
  
    /* Count how many have measured bandwidths so we know how to assign flags;
     * this must come before dirserv_compute_performance_thresholds() */
    dirserv_count_measured_bws(routers);
  
    dirserv_compute_performance_thresholds(omit_as_sybil);
  
    routerstatuses = smartlist_new();
    microdescriptors = smartlist_new();
  
    SMARTLIST_FOREACH_BEGIN(routers, routerinfo_t *, ri) {
      /* If it has a protover list and contains a protocol name greater than
       * MAX_PROTOCOL_NAME_LENGTH, skip it. */
      if (ri->protocol_list &&
          protover_contains_long_protocol_names(ri->protocol_list)) {
        continue;
      }
      if (ri->cache_info.published_on >= cutoff) {
        routerstatus_t *rs;
        vote_routerstatus_t *vrs;
        node_t *node = node_get_mutable_by_id(ri->cache_info.identity_digest);
        if (!node)
          continue;
  
        vrs = tor_malloc_zero(sizeof(vote_routerstatus_t));
        rs = &vrs->status;
        dirauth_set_routerstatus_from_routerinfo(rs, node, ri, now,
                                                 listbadexits);
  
        if (ri->cache_info.signing_key_cert) {
          memcpy(vrs->ed25519_id,
                 ri->cache_info.signing_key_cert->signing_key.pubkey,
                 ED25519_PUBKEY_LEN);
        }
  
        if (digestmap_get(omit_as_sybil, ri->cache_info.identity_digest))
          clear_status_flags_on_sybil(rs);
  
        if (!vote_on_reachability)
          rs->is_flagged_running = 0;
  
        vrs->version = version_from_platform(ri->platform);
        if (ri->protocol_list) {
          vrs->protocols = tor_strdup(ri->protocol_list);
        } else {
          vrs->protocols = tor_strdup(
                                  protover_compute_for_old_tor(vrs->version));
        }
        vrs->microdesc = dirvote_format_all_microdesc_vote_lines(ri, now,
                                                              microdescriptors);
  
        smartlist_add(routerstatuses, vrs);
      }
    } SMARTLIST_FOREACH_END(ri);
  
    {
      smartlist_t *added =
        microdescs_add_list_to_cache(get_microdesc_cache(),
                                     microdescriptors, SAVED_NOWHERE, 0);
      smartlist_free(added);
      smartlist_free(microdescriptors);
    }
  
    smartlist_free(routers);
    digestmap_free(omit_as_sybil, NULL);
  
    /* Apply guardfraction information to routerstatuses. */
    if (options->GuardfractionFile) {
      dirserv_read_guardfraction_file(options->GuardfractionFile,
                                      routerstatuses);
    }
  
    /* This pass through applies the measured bw lines to the routerstatuses */
    if (options->V3BandwidthsFile) {
      /* Only set bw_file_headers when V3BandwidthsFile is configured */
      bw_file_headers = smartlist_new();
      dirserv_read_measured_bandwidths(options->V3BandwidthsFile,
                                       routerstatuses, bw_file_headers,
                                       bw_file_digest256);
  
    } else {
      /*
       * No bandwidths file; clear the measured bandwidth cache in case we had
       * one last time around.
       */
      if (dirserv_get_measured_bw_cache_size() > 0) {
        dirserv_clear_measured_bw_cache();
      }
    }
  
    v3_out = tor_malloc_zero(sizeof(networkstatus_t));
  
    v3_out->type = NS_TYPE_VOTE;
    dirvote_get_preferred_voting_intervals(&timing);
    v3_out->published = now;
    {
      char tbuf[ISO_TIME_LEN+1];
      networkstatus_t *current_consensus =
        networkstatus_get_live_consensus(now);
      long last_consensus_interval; /* only used to pick a valid_after */
      if (current_consensus)
        last_consensus_interval = current_consensus->fresh_until -
          current_consensus->valid_after;
      else
        last_consensus_interval = options->TestingV3AuthInitialVotingInterval;
      v3_out->valid_after =
        voting_schedule_get_start_of_next_interval(now,
                                     (int)last_consensus_interval,
                                     options->TestingV3AuthVotingStartOffset);
      format_iso_time(tbuf, v3_out->valid_after);
      log_notice(LD_DIR,"Choosing valid-after time in vote as %s: "
                 "consensus_set=%d, last_interval=%d",
                 tbuf, current_consensus?1:0, (int)last_consensus_interval);
    }
    v3_out->fresh_until = v3_out->valid_after + timing.vote_interval;
    v3_out->valid_until = v3_out->valid_after +
      (timing.vote_interval * timing.n_intervals_valid);
    v3_out->vote_seconds = timing.vote_delay;
    v3_out->dist_seconds = timing.dist_delay;
    tor_assert(v3_out->vote_seconds > 0);
    tor_assert(v3_out->dist_seconds > 0);
    tor_assert(timing.n_intervals_valid > 0);
  
    v3_out->client_versions = client_versions;
    v3_out->server_versions = server_versions;
  
    /* These are hardwired, to avoid disaster. */
    v3_out->recommended_relay_protocols =
      tor_strdup("Cons=1-2 Desc=1-2 DirCache=1 HSDir=1 HSIntro=3 HSRend=1 "
                 "Link=4 Microdesc=1-2 Relay=2");
    v3_out->recommended_client_protocols =
      tor_strdup("Cons=1-2 Desc=1-2 DirCache=1 HSDir=1 HSIntro=3 HSRend=1 "
                 "Link=4 Microdesc=1-2 Relay=2");
    v3_out->required_client_protocols =
      tor_strdup("Cons=1-2 Desc=1-2 DirCache=1 HSDir=1 HSIntro=3 HSRend=1 "
                 "Link=4 Microdesc=1-2 Relay=2");
    v3_out->required_relay_protocols =
      tor_strdup("Cons=1 Desc=1 DirCache=1 HSDir=1 HSIntro=3 HSRend=1 "
                 "Link=3-4 Microdesc=1 Relay=1-2");
  
    /* We are not allowed to vote to require anything we don't have. */
    tor_assert(protover_all_supported(v3_out->required_relay_protocols, NULL));
    tor_assert(protover_all_supported(v3_out->required_client_protocols, NULL));
  
    /* We should not recommend anything we don't have. */
    tor_assert_nonfatal(protover_all_supported(
                                 v3_out->recommended_relay_protocols, NULL));
    tor_assert_nonfatal(protover_all_supported(
                                 v3_out->recommended_client_protocols, NULL));
  
    v3_out->package_lines = smartlist_new();
    {
      config_line_t *cl;
      for (cl = get_options()->RecommendedPackages; cl; cl = cl->next) {
        if (validate_recommended_package_line(cl->value))
          smartlist_add_strdup(v3_out->package_lines, cl->value);
      }
    }
  
    v3_out->known_flags = smartlist_new();
    smartlist_split_string(v3_out->known_flags,
                           DIRVOTE_UNIVERSAL_FLAGS,
                           0, SPLIT_SKIP_SPACE|SPLIT_IGNORE_BLANK, 0);
    if (vote_on_reachability)
      smartlist_add_strdup(v3_out->known_flags, "Running");
    if (listbadexits)
      smartlist_add_strdup(v3_out->known_flags, "BadExit");
    smartlist_sort_strings(v3_out->known_flags);
  
    if (options->ConsensusParams) {
      v3_out->net_params = smartlist_new();
      smartlist_split_string(v3_out->net_params,
                             options->ConsensusParams, NULL, 0, 0);
      smartlist_sort_strings(v3_out->net_params);
    }
    v3_out->bw_file_headers = bw_file_headers;
    memcpy(v3_out->bw_file_digest256, bw_file_digest256, DIGEST256_LEN);
  
    voter = tor_malloc_zero(sizeof(networkstatus_voter_info_t));
    voter->nickname = tor_strdup(options->Nickname);
    memcpy(voter->identity_digest, identity_digest, DIGEST_LEN);
    voter->sigs = smartlist_new();
    voter->address = hostname;
    voter->addr = addr;
    voter->dir_port = router_get_advertised_dir_port(options, 0);
    voter->or_port = router_get_advertised_or_port(options);
    voter->contact = tor_strdup(contact);
    if (options->V3AuthUseLegacyKey) {
      authority_cert_t *c = get_my_v3_legacy_cert();
      if (c) {
        if (crypto_pk_get_digest(c->identity_key, voter->legacy_id_digest)) {
          log_warn(LD_BUG, "Unable to compute digest of legacy v3 identity key");
          memset(voter->legacy_id_digest, 0, DIGEST_LEN);
        }
      }
    }
  
    v3_out->voters = smartlist_new();
    smartlist_add(v3_out->voters, voter);
    v3_out->cert = authority_cert_dup(cert);
    v3_out->routerstatus_list = routerstatuses;
    /* Note: networkstatus_digest is unset; it won't get set until we actually
     * format the vote. */
  
    return v3_out;
  }
  