text: /***************************************************************************
   *                                  _   _ ____  _
   *  Project                     ___| | | |  _ \| |
   *                             / __| | | | |_) | |
   *                            | (__| |_| |  _ <| |___
   *                             \___|\___/|_| \_\_____|
   *
   * Copyright (C) 1998 - 2013, Daniel Stenberg, <daniel@haxx.se>, et al.
   *
   * This software is licensed as described in the file COPYING, which
   * you should have received as part of this distribution. The terms
   * are also available at http://curl.haxx.se/docs/copyright.html.
   *
   * You may opt to use, copy, modify, merge, publish, distribute and/or sell
   * copies of the Software, and permit persons to whom the Software is
   * furnished to do so, under the terms of the COPYING file.
   *
   * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
   * KIND, either express or implied.
   *
   ***************************************************************************/
  
  /* This file is for implementing all "generic" SSL functions that all libcurl
     internals should use. It is then responsible for calling the proper
     "backend" function.
  
     SSL-functions in libcurl should call functions in this source file, and not
     to any specific SSL-layer.
  
     Curl_ssl_ - prefix for generic ones
     Curl_ossl_ - prefix for OpenSSL ones
     Curl_gtls_ - prefix for GnuTLS ones
     Curl_nss_ - prefix for NSS ones
     Curl_qssl_ - prefix for QsoSSL ones
     Curl_gskit_ - prefix for GSKit ones
     Curl_polarssl_ - prefix for PolarSSL ones
     Curl_cyassl_ - prefix for CyaSSL ones
     Curl_schannel_ - prefix for Schannel SSPI ones
     Curl_darwinssl_ - prefix for SecureTransport (Darwin) ones
  
     Note that this source code uses curlssl_* functions, and they are all
     defines/macros #defined by the lib-specific header files.
  
     "SSL/TLS Strong Encryption: An Introduction"
     http://httpd.apache.org/docs-2.0/ssl/ssl_intro.html
  */
  
  #include "curl_setup.h"
  
  #ifdef HAVE_SYS_TYPES_H
  #include <sys/types.h>
  #endif
  #ifdef HAVE_SYS_STAT_H
  #include <sys/stat.h>
  #endif
  #ifdef HAVE_FCNTL_H
  #include <fcntl.h>
  #endif
  
  #include "urldata.h"
  #define SSLGEN_C
  #include "sslgen.h" /* generic SSL protos etc */
  #include "ssluse.h" /* OpenSSL versions */
  #include "gtls.h"   /* GnuTLS versions */
  #include "nssg.h"   /* NSS versions */
  #include "qssl.h"   /* QSOSSL versions */
  #include "gskit.h"  /* Global Secure ToolKit versions */
  #include "polarssl.h" /* PolarSSL versions */
  #include "axtls.h"  /* axTLS versions */
  #include "cyassl.h"  /* CyaSSL versions */
  #include "curl_schannel.h" /* Schannel SSPI version */
  #include "curl_darwinssl.h" /* SecureTransport (Darwin) version */
  #include "slist.h"
  #include "sendf.h"
  #include "rawstr.h"
  #include "url.h"
  #include "curl_memory.h"
  #include "progress.h"
  #include "share.h"
  #include "timeval.h"
  
  #define _MPRINTF_REPLACE /* use our functions only */
  #include <XMCurl/mprintf.h>
  
  /* The last #include file should be: */
  #include "memdebug.h"
  
  /* convenience macro to check if this handle is using a shared SSL session */
  #define SSLSESSION_SHARED(data) (data->share &&                        \
                                   (data->share->specifier &             \
                                    (1<<CURL_LOCK_DATA_SSL_SESSION)))
  
  static bool safe_strequal(char* str1, char* str2)
  {
    if(str1 && str2)
      /* both pointers point to something then compare them */
      return (0 != Curl_raw_equal(str1, str2)) ? TRUE : FALSE;
    else
      /* if both pointers are NULL then treat them as equal */
      return (!str1 && !str2) ? TRUE : FALSE;
  }
  
  bool
  Curl_ssl_config_matches(struct ssl_config_data* data,
                          struct ssl_config_data* needle)
  {
    if((data->version == needle->version) &&
       (data->verifypeer == needle->verifypeer) &&
       (data->verifyhost == needle->verifyhost) &&
       safe_strequal(data->CApath, needle->CApath) &&
       safe_strequal(data->CAfile, needle->CAfile) &&
       safe_strequal(data->random_file, needle->random_file) &&
       safe_strequal(data->egdsocket, needle->egdsocket) &&
       safe_strequal(data->cipher_list, needle->cipher_list))
      return TRUE;
  
    return FALSE;
  }
  
  bool
  Curl_clone_ssl_config(struct ssl_config_data *source,
                        struct ssl_config_data *dest)
  {
    dest->sessionid = source->sessionid;
    dest->verifyhost = source->verifyhost;
    dest->verifypeer = source->verifypeer;
    dest->version = source->version;
  
    if(source->CAfile) {
      dest->CAfile = strdup(source->CAfile);
      if(!dest->CAfile)
        return FALSE;
    }
    else
      dest->CAfile = NULL;
  
    if(source->CApath) {
      dest->CApath = strdup(source->CApath);
      if(!dest->CApath)
        return FALSE;
    }
    else
      dest->CApath = NULL;
  
    if(source->cipher_list) {
      dest->cipher_list = strdup(source->cipher_list);
      if(!dest->cipher_list)
        return FALSE;
    }
    else
      dest->cipher_list = NULL;
  
    if(source->egdsocket) {
      dest->egdsocket = strdup(source->egdsocket);
      if(!dest->egdsocket)
        return FALSE;
    }
    else
      dest->egdsocket = NULL;
  
    if(source->random_file) {
      dest->random_file = strdup(source->random_file);
      if(!dest->random_file)
        return FALSE;
    }
    else
      dest->random_file = NULL;
  
    return TRUE;
  }
  
  void Curl_free_ssl_config(struct ssl_config_data* sslc)
  {
    Curl_safefree(sslc->CAfile);
    Curl_safefree(sslc->CApath);
    Curl_safefree(sslc->cipher_list);
    Curl_safefree(sslc->egdsocket);
    Curl_safefree(sslc->random_file);
  }
  
  
  /*
   * Curl_rand() returns a random unsigned integer, 32bit.
   *
   * This non-SSL function is put here only because this file is the only one
   * with knowledge of what the underlying SSL libraries provide in terms of
   * randomizers.
   *
   * NOTE: 'data' may be passed in as NULL when coming from external API without
   * easy handle!
   *
   */
  
  unsigned int Curl_rand(struct SessionHandle *data)
  {
    unsigned int r;
    static unsigned int randseed;
    static bool seeded = FALSE;
  
  #ifndef have_curlssl_random
    (void)data;
  #else
    if(data) {
      Curl_ssl_random(data, (unsigned char *)&r, sizeof(r));
      return r;
    }
  #endif
  
  #ifdef RANDOM_FILE
    if(!seeded) {
      /* if there's a random file to read a seed from, use it */
      int fd = open(RANDOM_FILE, O_RDONLY);
      if(fd > -1) {
        /* read random data into the randseed variable */
        ssize_t nread = read(fd, &randseed, sizeof(randseed));
        if(nread == sizeof(randseed))
          seeded = TRUE;
        close(fd);
      }
    }
  #endif
  
    if(!seeded) {
      struct timeval now = curlx_tvnow();
      randseed += (unsigned int)now.tv_usec + (unsigned int)now.tv_sec;
      randseed = randseed * 1103515245 + 12345;
      randseed = randseed * 1103515245 + 12345;
      randseed = randseed * 1103515245 + 12345;
      seeded = TRUE;
    }
  
    /* Return an unsigned 32-bit pseudo-random number. */
    r = randseed = randseed * 1103515245 + 12345;
    return (r << 16) | ((r >> 16) & 0xFFFF);
  }
  
  #ifdef USE_SSL
  
  /* "global" init done? */
  static bool init_ssl=FALSE;
  
  /**
   * Global SSL init
   *
   * @retval 0 error initializing SSL
   * @retval 1 SSL initialized successfully
   */
  int Curl_ssl_init(void)
  {
    /* make sure this is only done once */
    if(init_ssl)
      return 1;
    init_ssl = TRUE; /* never again */
  
    return curlssl_init();
  }
  
  
  /* Global cleanup */
  void Curl_ssl_cleanup(void)
  {
    if(init_ssl) {
      /* only cleanup if we did a previous init */
      curlssl_cleanup();
      init_ssl = FALSE;
    }
  }
  
  CURLcode
  Curl_ssl_connect(struct connectdata *conn, int sockindex)
  {
    CURLcode res;
    /* mark this is being ssl-enabled from here on. */
    conn->ssl[sockindex].use = TRUE;
    conn->ssl[sockindex].state = ssl_connection_negotiating;
  
    res = curlssl_connect(conn, sockindex);
  
    if(!res)
      Curl_pgrsTime(conn->data, TIMER_APPCONNECT); /* SSL is connected */
  
    return res;
  }
  
  CURLcode
  Curl_ssl_connect_nonblocking(struct connectdata *conn, int sockindex,
                               bool *done)
  {
    CURLcode res;
    /* mark this is being ssl requested from here on. */
    conn->ssl[sockindex].use = TRUE;
  #ifdef curlssl_connect_nonblocking
    res = curlssl_connect_nonblocking(conn, sockindex, done);
  #else
    *done = TRUE; /* fallback to BLOCKING */
    res = curlssl_connect(conn, sockindex);
  #endif /* non-blocking connect support */
    if(!res && *done)
      Curl_pgrsTime(conn->data, TIMER_APPCONNECT); /* SSL is connected */
    return res;
  }
  
  /*
   * Check if there's a session ID for the given connection in the cache, and if
   * there's one suitable, it is provided. Returns TRUE when no entry matched.
   */
  int Curl_ssl_getsessionid(struct connectdata *conn,
                            void **ssl_sessionid,
                            size_t *idsize) /* set 0 if unknown */
  {
    struct curl_ssl_session *check;
    struct SessionHandle *data = conn->data;
    size_t i;
    long *general_age;
    bool no_match = TRUE;
  
    *ssl_sessionid = NULL;
  
    if(!conn->ssl_config.sessionid)
      /* session ID re-use is disabled */
      return TRUE;
  
    /* Lock if shared */
    if(SSLSESSION_SHARED(data)) {
      Curl_share_lock(data, CURL_LOCK_DATA_SSL_SESSION, CURL_LOCK_ACCESS_SINGLE);
      general_age = &data->share->sessionage;
    }
    else
      general_age = &data->state.sessionage;
  
    for(i = 0; i < data->set.ssl.max_ssl_sessions; i++) {
      check = &data->state.session[i];
      if(!check->sessionid)
        /* not session ID means blank entry */
        continue;
      if(Curl_raw_equal(conn->host.name, check->name) &&
         (conn->remote_port == check->remote_port) &&
         Curl_ssl_config_matches(&conn->ssl_config, &check->ssl_config)) {
        /* yes, we have a session ID! */
        (*general_age)++;          /* increase general age */
        check->age = *general_age; /* set this as used in this age */
        *ssl_sessionid = check->sessionid;
        if(idsize)
          *idsize = check->idsize;
        no_match = FALSE;
        break;
      }
    }
  
    /* Unlock */
    if(SSLSESSION_SHARED(data))
      Curl_share_unlock(data, CURL_LOCK_DATA_SSL_SESSION);
  
    return no_match;
  }
  
  /*
   * Kill a single session ID entry in the cache.
   */
  void Curl_ssl_kill_session(struct curl_ssl_session *session)
  {
    if(session->sessionid) {
      /* defensive check */
  
      /* free the ID the SSL-layer specific way */
      curlssl_session_free(session->sessionid);
  
      session->sessionid = NULL;
      session->age = 0; /* fresh */
  
      Curl_free_ssl_config(&session->ssl_config);
  
      Curl_safefree(session->name);
    }
  }
  
  /*
   * Delete the given session ID from the cache.
   */
  void Curl_ssl_delsessionid(struct connectdata *conn, void *ssl_sessionid)
  {
    size_t i;
    struct SessionHandle *data=conn->data;
  
    if(SSLSESSION_SHARED(data))
      Curl_share_lock(data, CURL_LOCK_DATA_SSL_SESSION, CURL_LOCK_ACCESS_SINGLE);
  
    for(i = 0; i < data->set.ssl.max_ssl_sessions; i++) {
      struct curl_ssl_session *check = &data->state.session[i];
  
      if(check->sessionid == ssl_sessionid) {
        Curl_ssl_kill_session(check);
        break;
      }
    }
  
    if(SSLSESSION_SHARED(data))
      Curl_share_unlock(data, CURL_LOCK_DATA_SSL_SESSION);
  }
  
  /*
   * Store session id in the session cache. The ID passed on to this function
   * must already have been extracted and allocated the proper way for the SSL
   * layer. Curl_XXXX_session_free() will be called to free/kill the session ID
   * later on.
   */
  CURLcode Curl_ssl_addsessionid(struct connectdata *conn,
                                 void *ssl_sessionid,
                                 size_t idsize)
  {
    size_t i;
    struct SessionHandle *data=conn->data; /* the mother of all structs */
    struct curl_ssl_session *store = &data->state.session[0];
    long oldest_age=data->state.session[0].age; /* zero if unused */
    char *clone_host;
    long *general_age;
  
    /* Even though session ID re-use might be disabled, that only disables USING
       IT. We still store it here in case the re-using is again enabled for an
       upcoming transfer */
  
    clone_host = strdup(conn->host.name);
    if(!clone_host)
      return CURLE_OUT_OF_MEMORY; /* bail out */
  
    /* Now we should add the session ID and the host name to the cache, (remove
       the oldest if necessary) */
  
    /* If using shared SSL session, lock! */
    if(SSLSESSION_SHARED(data)) {
      Curl_share_lock(data, CURL_LOCK_DATA_SSL_SESSION, CURL_LOCK_ACCESS_SINGLE);
      general_age = &data->share->sessionage;
    }
    else {
      general_age = &data->state.sessionage;
    }
  
    /* find an empty slot for us, or find the oldest */
    for(i = 1; (i < data->set.ssl.max_ssl_sessions) &&
          data->state.session[i].sessionid; i++) {
      if(data->state.session[i].age < oldest_age) {
        oldest_age = data->state.session[i].age;
        store = &data->state.session[i];
      }
    }
    if(i == data->set.ssl.max_ssl_sessions)
      /* cache is full, we must "kill" the oldest entry! */
      Curl_ssl_kill_session(store);
    else
      store = &data->state.session[i]; /* use this slot */
  
    /* now init the session struct wisely */
    store->sessionid = ssl_sessionid;
    store->idsize = idsize;
    store->age = *general_age;    /* set current age */
    if(store->name)
      /* free it if there's one already present */
      free(store->name);
    store->name = clone_host;               /* clone host name */
    store->remote_port = conn->remote_port; /* port number */
  
  
    /* Unlock */
    if(SSLSESSION_SHARED(data))
      Curl_share_unlock(data, CURL_LOCK_DATA_SSL_SESSION);
  
    if(!Curl_clone_ssl_config(&conn->ssl_config, &store->ssl_config)) {
      store->sessionid = NULL; /* let caller free sessionid */
      free(clone_host);
      return CURLE_OUT_OF_MEMORY;
    }
  
    return CURLE_OK;
  }
  
  
  void Curl_ssl_close_all(struct SessionHandle *data)
  {
    size_t i;
    /* kill the session ID cache if not shared */
    if(data->state.session && !SSLSESSION_SHARED(data)) {
      for(i = 0; i < data->set.ssl.max_ssl_sessions; i++)
        /* the single-killer function handles empty table slots */
        Curl_ssl_kill_session(&data->state.session[i]);
  
      /* free the cache data */
      Curl_safefree(data->state.session);
    }
  
    curlssl_close_all(data);
  }
  
  void Curl_ssl_close(struct connectdata *conn, int sockindex)
  {
    DEBUGASSERT((sockindex <= 1) && (sockindex >= -1));
    curlssl_close(conn, sockindex);
  }
  
  CURLcode Curl_ssl_shutdown(struct connectdata *conn, int sockindex)
  {
    if(curlssl_shutdown(conn, sockindex))
      return CURLE_SSL_SHUTDOWN_FAILED;
  
    conn->ssl[sockindex].use = FALSE; /* get back to ordinary socket usage */
    conn->ssl[sockindex].state = ssl_connection_none;
  
    conn->recv[sockindex] = Curl_recv_plain;
    conn->send[sockindex] = Curl_send_plain;
  
    return CURLE_OK;
  }
  
  /* Selects an SSL crypto engine
   */
  CURLcode Curl_ssl_set_engine(struct SessionHandle *data, const char *engine)
  {
    return curlssl_set_engine(data, engine);
  }
  
  /* Selects the default SSL crypto engine
   */
  CURLcode Curl_ssl_set_engine_default(struct SessionHandle *data)
  {
    return curlssl_set_engine_default(data);
  }
  
  /* Return list of OpenSSL crypto engine names. */
  struct curl_slist *Curl_ssl_engines_list(struct SessionHandle *data)
  {
    return curlssl_engines_list(data);
  }
  
  /*
   * This sets up a session ID cache to the specified size. Make sure this code
   * is agnostic to what underlying SSL technology we use.
   */
  CURLcode Curl_ssl_initsessions(struct SessionHandle *data, size_t amount)
  {
    struct curl_ssl_session *session;
  
    if(data->state.session)
      /* this is just a precaution to prevent multiple inits */
      return CURLE_OK;
  
    session = calloc(amount, sizeof(struct curl_ssl_session));
    if(!session)
      return CURLE_OUT_OF_MEMORY;
  
    /* store the info in the SSL section */
    data->set.ssl.max_ssl_sessions = amount;
    data->state.session = session;
    data->state.sessionage = 1; /* this is brand new */
    return CURLE_OK;
  }
  
  size_t Curl_ssl_version(char *buffer, size_t size)
  {
    return curlssl_version(buffer, size);
  }
  
  /*
   * This function tries to determine connection status.
   *
   * Return codes:
   *     1 means the connection is still in place
   *     0 means the connection has been closed
   *    -1 means the connection status is unknown
   */
  int Curl_ssl_check_cxn(struct connectdata *conn)
  {
    return curlssl_check_cxn(conn);
  }
  
  bool Curl_ssl_data_pending(const struct connectdata *conn,
                             int connindex)
  {
    return curlssl_data_pending(conn, connindex);
  }
  
  void Curl_ssl_free_certinfo(struct SessionHandle *data)
  {
    int i;
    struct curl_certinfo *ci = &data->info.certs;
    if(ci->num_of_certs) {
      /* free all individual lists used */
      for(i=0; i<ci->num_of_certs; i++) {
        curl_slist_free_all(ci->certinfo[i]);
        ci->certinfo[i] = NULL;
      }
      free(ci->certinfo); /* free the actual array too */
      ci->certinfo = NULL;
      ci->num_of_certs = 0;
    }
  }
  
  int Curl_ssl_init_certinfo(struct SessionHandle * data,
                             int num)
  {
    struct curl_certinfo * ci = &data->info.certs;
    struct curl_slist * * table;
  
    /* Initialize the certificate information structures. Return 0 if OK, else 1.
     */
    Curl_ssl_free_certinfo(data);
    ci->num_of_certs = num;
    table = calloc((size_t) num, sizeof(struct curl_slist *));
    if(!table)
      return 1;
  
    ci->certinfo = table;
    return 0;
  }
  
  CURLcode Curl_ssl_push_certinfo_len(struct SessionHandle *data,
                                      int certnum,
                                      const char *label,
                                      const char *value,
                                      size_t valuelen)
  {
    struct curl_certinfo * ci = &data->info.certs;
    char * output;
    struct curl_slist * nl;
    CURLcode res = CURLE_OK;
  
    /* Add an information record for a particular certificate. */
    output = curl_maprintf("%s:%.*s", label, valuelen, value);
    if(!output)
      return CURLE_OUT_OF_MEMORY;
  
    nl = Curl_slist_append_nodup(ci->certinfo[certnum], output);
    if(!nl) {
      free(output);
      curl_slist_free_all(ci->certinfo[certnum]);
      res = CURLE_OUT_OF_MEMORY;
    }
  
    ci->certinfo[certnum] = nl;
    return res;
  }
  
  /*
   * This is a convenience function for push_certinfo_len that takes a zero
   * terminated value.
   */
  CURLcode Curl_ssl_push_certinfo(struct SessionHandle *data,
                                  int certnum,
                                  const char *label,
                                  const char *value)
  {
    size_t valuelen = strlen(value);
  
    return Curl_ssl_push_certinfo_len(data, certnum, label, value, valuelen);
  }
  
  /* these functions are only provided by some SSL backends */
  
  #ifdef have_curlssl_random
  void Curl_ssl_random(struct SessionHandle *data,
                       unsigned char *entropy,
                       size_t length)
  {
    curlssl_random(data, entropy, length);
  }
  #endif
  
  #ifdef have_curlssl_md5sum
  void Curl_ssl_md5sum(unsigned char *tmp, /* input */
                       size_t tmplen,
                       unsigned char *md5sum, /* output */
                       size_t md5len)
  {
    curlssl_md5sum(tmp, tmplen, md5sum, md5len);
  }
  #endif
  
  #endif /* USE_SSL */
  