text: /*
   * Copyright 2016-2021 The OpenSSL Project Authors. All Rights Reserved.
   *
   * Licensed under the Apache License 2.0 (the "License").  You may not use
   * this file except in compliance with the License.  You can obtain a copy
   * in the file LICENSE in the source distribution or at
   * https://www.openssl.org/source/license.html
   */
  
  #ifndef _GNU_SOURCE
  # define _GNU_SOURCE
  #endif
  
  /*
   * VC configurations may define UNICODE, to indicate to the C RTL that
   * WCHAR functions are preferred.
   * This affects functions like gai_strerror(), which is implemented as
   * an alias macro for gai_strerrorA() (which returns a const char *) or
   * gai_strerrorW() (which returns a const WCHAR *).  This source file
   * assumes POSIX declarations, so prefer the non-UNICODE definitions.
   */
  #undef UNICODE
  
  #include <assert.h>
  #include <string.h>
  
  #include "bio_local.h"
  #include <openssl/crypto.h>
  
  #ifndef OPENSSL_NO_SOCK
  #include <openssl/err.h>
  #include <openssl/buffer.h>
  #include "internal/thread_once.h"
  
  CRYPTO_RWLOCK *bio_lookup_lock;
  static CRYPTO_ONCE bio_lookup_init = CRYPTO_ONCE_STATIC_INIT;
  
  /*
   * Throughout this file and bio_local.h, the existence of the macro
   * AI_PASSIVE is used to detect the availability of struct addrinfo,
   * getnameinfo() and getaddrinfo().  If that macro doesn't exist,
   * we use our own implementation instead, using gethostbyname,
   * getservbyname and a few other.
   */
  
  /**********************************************************************
   *
   * Address structure
   *
   */
  
  BIO_ADDR *BIO_ADDR_new(void)
  {
      BIO_ADDR *ret = OPENSSL_zalloc(sizeof(*ret));
  
      if (ret == NULL) {
          ERR_raise(ERR_LIB_BIO, ERR_R_MALLOC_FAILURE);
          return NULL;
      }
  
      ret->sa.sa_family = AF_UNSPEC;
      return ret;
  }
  
  void BIO_ADDR_free(BIO_ADDR *ap)
  {
      OPENSSL_free(ap);
  }
  
  void BIO_ADDR_clear(BIO_ADDR *ap)
  {
      memset(ap, 0, sizeof(*ap));
      ap->sa.sa_family = AF_UNSPEC;
  }
  
  /*
   * BIO_ADDR_make - non-public routine to fill a BIO_ADDR with the contents
   * of a struct sockaddr.
   */
  int BIO_ADDR_make(BIO_ADDR *ap, const struct sockaddr *sa)
  {
      if (sa->sa_family == AF_INET) {
          memcpy(&(ap->s_in), sa, sizeof(struct sockaddr_in));
          return 1;
      }
  #ifdef AF_INET6
      if (sa->sa_family == AF_INET6) {
          memcpy(&(ap->s_in6), sa, sizeof(struct sockaddr_in6));
          return 1;
      }
  #endif
  #ifdef AF_UNIX
      if (sa->sa_family == AF_UNIX) {
          memcpy(&(ap->s_un), sa, sizeof(struct sockaddr_un));
          return 1;
      }
  #endif
  
      return 0;
  }
  
  int BIO_ADDR_rawmake(BIO_ADDR *ap, int family,
                       const void *where, size_t wherelen,
                       unsigned short port)
  {
  #ifdef AF_UNIX
      if (family == AF_UNIX) {
          if (wherelen + 1 > sizeof(ap->s_un.sun_path))
              return 0;
          memset(&ap->s_un, 0, sizeof(ap->s_un));
          ap->s_un.sun_family = family;
          strncpy(ap->s_un.sun_path, where, sizeof(ap->s_un.sun_path) - 1);
          return 1;
      }
  #endif
      if (family == AF_INET) {
          if (wherelen != sizeof(struct in_addr))
              return 0;
          memset(&ap->s_in, 0, sizeof(ap->s_in));
          ap->s_in.sin_family = family;
          ap->s_in.sin_port = port;
          ap->s_in.sin_addr = *(struct in_addr *)where;
          return 1;
      }
  #ifdef AF_INET6
      if (family == AF_INET6) {
          if (wherelen != sizeof(struct in6_addr))
              return 0;
          memset(&ap->s_in6, 0, sizeof(ap->s_in6));
          ap->s_in6.sin6_family = family;
          ap->s_in6.sin6_port = port;
          ap->s_in6.sin6_addr = *(struct in6_addr *)where;
          return 1;
      }
  #endif
  
      return 0;
  }
  
  int BIO_ADDR_family(const BIO_ADDR *ap)
  {
      return ap->sa.sa_family;
  }
  
  int BIO_ADDR_rawaddress(const BIO_ADDR *ap, void *p, size_t *l)
  {
      size_t len = 0;
      const void *addrptr = NULL;
  
      if (ap->sa.sa_family == AF_INET) {
          len = sizeof(ap->s_in.sin_addr);
          addrptr = &ap->s_in.sin_addr;
      }
  #ifdef AF_INET6
      else if (ap->sa.sa_family == AF_INET6) {
          len = sizeof(ap->s_in6.sin6_addr);
          addrptr = &ap->s_in6.sin6_addr;
      }
  #endif
  #ifdef AF_UNIX
      else if (ap->sa.sa_family == AF_UNIX) {
          len = strlen(ap->s_un.sun_path);
          addrptr = &ap->s_un.sun_path;
      }
  #endif
  
      if (addrptr == NULL)
          return 0;
  
      if (p != NULL) {
          memcpy(p, addrptr, len);
      }
      if (l != NULL)
          *l = len;
  
      return 1;
  }
  
  unsigned short BIO_ADDR_rawport(const BIO_ADDR *ap)
  {
      if (ap->sa.sa_family == AF_INET)
          return ap->s_in.sin_port;
  #ifdef AF_INET6
      if (ap->sa.sa_family == AF_INET6)
          return ap->s_in6.sin6_port;
  #endif
      return 0;
  }
  
  /*-
   * addr_strings - helper function to get host and service names
   * @ap: the BIO_ADDR that has the input info
   * @numeric: 0 if actual names should be returned, 1 if the numeric
   * representation should be returned.
   * @hostname: a pointer to a pointer to a memory area to store the
   * host name or numeric representation.  Unused if NULL.
   * @service: a pointer to a pointer to a memory area to store the
   * service name or numeric representation.  Unused if NULL.
   *
   * The return value is 0 on failure, with the error code in the error
   * stack, and 1 on success.
   */
  static int addr_strings(const BIO_ADDR *ap, int numeric,
                          char **hostname, char **service)
  {
      if (BIO_sock_init() != 1)
          return 0;
  
      if (1) {
  #ifdef AI_PASSIVE
          int ret = 0;
          char host[NI_MAXHOST] = "", serv[NI_MAXSERV] = "";
          int flags = 0;
  
          if (numeric)
              flags |= NI_NUMERICHOST | NI_NUMERICSERV;
  
          if ((ret = getnameinfo(BIO_ADDR_sockaddr(ap),
                                 BIO_ADDR_sockaddr_size(ap),
                                 host, sizeof(host), serv, sizeof(serv),
                                 flags)) != 0) {
  # ifdef EAI_SYSTEM
              if (ret == EAI_SYSTEM) {
                  ERR_raise_data(ERR_LIB_SYS, get_last_socket_error(),
                                 "calling getnameinfo()");
              } else
  # endif
              {
                  ERR_raise_data(ERR_LIB_BIO, ERR_R_SYS_LIB, gai_strerror(ret));
              }
              return 0;
          }
  
          /* VMS getnameinfo() has a bug, it doesn't fill in serv, which
           * leaves it with whatever garbage that happens to be there.
           * However, we initialise serv with the empty string (serv[0]
           * is therefore NUL), so it gets real easy to detect when things
           * didn't go the way one might expect.
           */
          if (serv[0] == '\0') {
              BIO_snprintf(serv, sizeof(serv), "%d",
                           ntohs(BIO_ADDR_rawport(ap)));
          }
  
          if (hostname != NULL)
              *hostname = OPENSSL_strdup(host);
          if (service != NULL)
              *service = OPENSSL_strdup(serv);
      } else {
  #endif
          if (hostname != NULL)
              *hostname = OPENSSL_strdup(inet_ntoa(ap->s_in.sin_addr));
          if (service != NULL) {
              char serv[6];        /* port is 16 bits => max 5 decimal digits */
              BIO_snprintf(serv, sizeof(serv), "%d", ntohs(ap->s_in.sin_port));
              *service = OPENSSL_strdup(serv);
          }
      }
  
      if ((hostname != NULL && *hostname == NULL)
              || (service != NULL && *service == NULL)) {
          if (hostname != NULL) {
              OPENSSL_free(*hostname);
              *hostname = NULL;
          }
          if (service != NULL) {
              OPENSSL_free(*service);
              *service = NULL;
          }
          ERR_raise(ERR_LIB_BIO, ERR_R_MALLOC_FAILURE);
          return 0;
      }
  
      return 1;
  }
  
  char *BIO_ADDR_hostname_string(const BIO_ADDR *ap, int numeric)
  {
      char *hostname = NULL;
  
      if (addr_strings(ap, numeric, &hostname, NULL))
          return hostname;
  
      return NULL;
  }
  
  char *BIO_ADDR_service_string(const BIO_ADDR *ap, int numeric)
  {
      char *service = NULL;
  
      if (addr_strings(ap, numeric, NULL, &service))
          return service;
  
      return NULL;
  }
  
  char *BIO_ADDR_path_string(const BIO_ADDR *ap)
  {
  #ifdef AF_UNIX
      if (ap->sa.sa_family == AF_UNIX)
          return OPENSSL_strdup(ap->s_un.sun_path);
  #endif
      return NULL;
  }
  
  /*
   * BIO_ADDR_sockaddr - non-public routine to return the struct sockaddr
   * for a given BIO_ADDR.  In reality, this is simply a type safe cast.
   * The returned struct sockaddr is const, so it can't be tampered with.
   */
  const struct sockaddr *BIO_ADDR_sockaddr(const BIO_ADDR *ap)
  {
      return &(ap->sa);
  }
  
  /*
   * BIO_ADDR_sockaddr_noconst - non-public function that does the same
   * as BIO_ADDR_sockaddr, but returns a non-const.  USE WITH CARE, as
   * it allows you to tamper with the data (and thereby the contents
   * of the input BIO_ADDR).
   */
  struct sockaddr *BIO_ADDR_sockaddr_noconst(BIO_ADDR *ap)
  {
      return &(ap->sa);
  }
  
  /*
   * BIO_ADDR_sockaddr_size - non-public function that returns the size
   * of the struct sockaddr the BIO_ADDR is using.  If the protocol family
   * isn't set or is something other than AF_INET, AF_INET6 or AF_UNIX,
   * the size of the BIO_ADDR type is returned.
   */
  socklen_t BIO_ADDR_sockaddr_size(const BIO_ADDR *ap)
  {
      if (ap->sa.sa_family == AF_INET)
          return sizeof(ap->s_in);
  #ifdef AF_INET6
      if (ap->sa.sa_family == AF_INET6)
          return sizeof(ap->s_in6);
  #endif
  #ifdef AF_UNIX
      if (ap->sa.sa_family == AF_UNIX)
          return sizeof(ap->s_un);
  #endif
      return sizeof(*ap);
  }
  
  /**********************************************************************
   *
   * Address info database
   *
   */
  
  const BIO_ADDRINFO *BIO_ADDRINFO_next(const BIO_ADDRINFO *bai)
  {
      if (bai != NULL)
          return bai->bai_next;
      return NULL;
  }
  
  int BIO_ADDRINFO_family(const BIO_ADDRINFO *bai)
  {
      if (bai != NULL)
          return bai->bai_family;
      return 0;
  }
  
  int BIO_ADDRINFO_socktype(const BIO_ADDRINFO *bai)
  {
      if (bai != NULL)
          return bai->bai_socktype;
      return 0;
  }
  
  int BIO_ADDRINFO_protocol(const BIO_ADDRINFO *bai)
  {
      if (bai != NULL) {
          if (bai->bai_protocol != 0)
              return bai->bai_protocol;
  
  #ifdef AF_UNIX
          if (bai->bai_family == AF_UNIX)
              return 0;
  #endif
  
          switch (bai->bai_socktype) {
          case SOCK_STREAM:
              return IPPROTO_TCP;
          case SOCK_DGRAM:
              return IPPROTO_UDP;
          default:
              break;
          }
      }
      return 0;
  }
  
  /*
   * BIO_ADDRINFO_sockaddr_size - non-public function that returns the size
   * of the struct sockaddr inside the BIO_ADDRINFO.
   */
  socklen_t BIO_ADDRINFO_sockaddr_size(const BIO_ADDRINFO *bai)
  {
      if (bai != NULL)
          return bai->bai_addrlen;
      return 0;
  }
  
  /*
   * BIO_ADDRINFO_sockaddr - non-public function that returns bai_addr
   * as the struct sockaddr it is.
   */
  const struct sockaddr *BIO_ADDRINFO_sockaddr(const BIO_ADDRINFO *bai)
  {
      if (bai != NULL)
          return bai->bai_addr;
      return NULL;
  }
  
  const BIO_ADDR *BIO_ADDRINFO_address(const BIO_ADDRINFO *bai)
  {
      if (bai != NULL)
          return (BIO_ADDR *)bai->bai_addr;
      return NULL;
  }
  
  void BIO_ADDRINFO_free(BIO_ADDRINFO *bai)
  {
      if (bai == NULL)
          return;
  
  #ifdef AI_PASSIVE
  # ifdef AF_UNIX
  #  define _cond bai->bai_family != AF_UNIX
  # else
  #  define _cond 1
  # endif
      if (_cond) {
          freeaddrinfo(bai);
          return;
      }
  #endif
  
      /* Free manually when we know that addrinfo_wrap() was used.
       * See further comment above addrinfo_wrap()
       */
      while (bai != NULL) {
          BIO_ADDRINFO *next = bai->bai_next;
          OPENSSL_free(bai->bai_addr);
          OPENSSL_free(bai);
          bai = next;
      }
  }
  
  /**********************************************************************
   *
   * Service functions
   *
   */
  
  /*-
   * The specs in hostserv can take these forms:
   *
   * host:service         => *host = "host", *service = "service"
   * host:*               => *host = "host", *service = NULL
   * host:                => *host = "host", *service = NULL
   * :service             => *host = NULL, *service = "service"
   * *:service            => *host = NULL, *service = "service"
   *
   * in case no : is present in the string, the result depends on
   * hostserv_prio, as follows:
   *
   * when hostserv_prio == BIO_PARSE_PRIO_HOST
   * host                 => *host = "host", *service untouched
   *
   * when hostserv_prio == BIO_PARSE_PRIO_SERV
   * service              => *host untouched, *service = "service"
   *
   */
  int BIO_parse_hostserv(const char *hostserv, char **host, char **service,
                         enum BIO_hostserv_priorities hostserv_prio)
  {
      const char *h = NULL; size_t hl = 0;
      const char *p = NULL; size_t pl = 0;
  
      if (*hostserv == '[') {
          if ((p = strchr(hostserv, ']')) == NULL)
              goto spec_err;
          h = hostserv + 1;
          hl = p - h;
          p++;
          if (*p == '\0')
              p = NULL;
          else if (*p != ':')
              goto spec_err;
          else {
              p++;
              pl = strlen(p);
          }
      } else {
          const char *p2 = strrchr(hostserv, ':');
          p = strchr(hostserv, ':');
  
          /*-
           * Check for more than one colon.  There are three possible
           * interpretations:
           * 1. IPv6 address with port number, last colon being separator.
           * 2. IPv6 address only.
           * 3. IPv6 address only if hostserv_prio == BIO_PARSE_PRIO_HOST,
           *    IPv6 address and port number if hostserv_prio == BIO_PARSE_PRIO_SERV
           * Because of this ambiguity, we currently choose to make it an
           * error.
           */
          if (p != p2)
              goto amb_err;
  
          if (p != NULL) {
              h = hostserv;
              hl = p - h;
              p++;
              pl = strlen(p);
          } else if (hostserv_prio == BIO_PARSE_PRIO_HOST) {
              h = hostserv;
              hl = strlen(h);
          } else {
              p = hostserv;
              pl = strlen(p);
          }
      }
  
      if (p != NULL && strchr(p, ':'))
          goto spec_err;
  
      if (h != NULL && host != NULL) {
          if (hl == 0
              || (hl == 1 && h[0] == '*')) {
              *host = NULL;
          } else {
              *host = OPENSSL_strndup(h, hl);
              if (*host == NULL)
                  goto memerr;
          }
      }
      if (p != NULL && service != NULL) {
          if (pl == 0
              || (pl == 1 && p[0] == '*')) {
              *service = NULL;
          } else {
              *service = OPENSSL_strndup(p, pl);
              if (*service == NULL)
                  goto memerr;
          }
      }
  
      return 1;
   amb_err:
      ERR_raise(ERR_LIB_BIO, BIO_R_AMBIGUOUS_HOST_OR_SERVICE);
      return 0;
   spec_err:
      ERR_raise(ERR_LIB_BIO, BIO_R_MALFORMED_HOST_OR_SERVICE);
      return 0;
   memerr:
      ERR_raise(ERR_LIB_BIO, ERR_R_MALLOC_FAILURE);
      return 0;
  }
  
  /* addrinfo_wrap is used to build our own addrinfo "chain".
   * (it has only one entry, so calling it a chain may be a stretch)
   * It should ONLY be called when getaddrinfo() and friends
   * aren't available, OR when dealing with a non IP protocol
   * family, such as AF_UNIX
   *
   * the return value is 1 on success, or 0 on failure, which
   * only happens if a memory allocation error occurred.
   */
  static int addrinfo_wrap(int family, int socktype,
                           const void *where, size_t wherelen,
                           unsigned short port,
                           BIO_ADDRINFO **bai)
  {
      if ((*bai = OPENSSL_zalloc(sizeof(**bai))) == NULL) {
          ERR_raise(ERR_LIB_BIO, ERR_R_MALLOC_FAILURE);
          return 0;
      }
  
      (*bai)->bai_family = family;
      (*bai)->bai_socktype = socktype;
      if (socktype == SOCK_STREAM)
          (*bai)->bai_protocol = IPPROTO_TCP;
      if (socktype == SOCK_DGRAM)
          (*bai)->bai_protocol = IPPROTO_UDP;
  #ifdef AF_UNIX
      if (family == AF_UNIX)
          (*bai)->bai_protocol = 0;
  #endif
      {
          /* Magic: We know that BIO_ADDR_sockaddr_noconst is really
             just an advanced cast of BIO_ADDR* to struct sockaddr *
             by the power of union, so while it may seem that we're
             creating a memory leak here, we are not.  It will be
             all right. */
          BIO_ADDR *addr = BIO_ADDR_new();
          if (addr != NULL) {
              BIO_ADDR_rawmake(addr, family, where, wherelen, port);
              (*bai)->bai_addr = BIO_ADDR_sockaddr_noconst(addr);
          }
      }
      (*bai)->bai_next = NULL;
      if ((*bai)->bai_addr == NULL) {
          BIO_ADDRINFO_free(*bai);
          *bai = NULL;
          return 0;
      }
      return 1;
  }
  
  DEFINE_RUN_ONCE_STATIC(do_bio_lookup_init)
  {
      bio_lookup_lock = CRYPTO_THREAD_lock_new();
      return bio_lookup_lock != NULL;
  }
  
  int BIO_lookup(const char *host, const char *service,
                 enum BIO_lookup_type lookup_type,
                 int family, int socktype, BIO_ADDRINFO **res)
  {
      return BIO_lookup_ex(host, service, lookup_type, family, socktype, 0, res);
  }
  
  /*-
   * BIO_lookup_ex - look up the host and service you want to connect to.
   * @host: the host (or node, in case family == AF_UNIX) you want to connect to.
   * @service: the service you want to connect to.
   * @lookup_type: declare intent with the result, client or server.
   * @family: the address family you want to use.  Use AF_UNSPEC for any, or
   *  AF_INET, AF_INET6 or AF_UNIX.
   * @socktype: The socket type you want to use.  Can be SOCK_STREAM, SOCK_DGRAM
   *  or 0 for all.
   * @protocol: The protocol to use, e.g. IPPROTO_TCP or IPPROTO_UDP or 0 for all.
   *            Note that some platforms may not return IPPROTO_SCTP without
   *            explicitly requesting it (i.e. IPPROTO_SCTP may not be returned
   *            with 0 for the protocol)
   * @res: Storage place for the resulting list of returned addresses
   *
   * This will do a lookup of the host and service that you want to connect to.
   * It returns a linked list of different addresses you can try to connect to.
   *
   * When no longer needed you should call BIO_ADDRINFO_free() to free the result.
   *
   * The return value is 1 on success or 0 in case of error.
   */
  int BIO_lookup_ex(const char *host, const char *service, int lookup_type,
                    int family, int socktype, int protocol, BIO_ADDRINFO **res)
  {
      int ret = 0;                 /* Assume failure */
  
      switch(family) {
      case AF_INET:
  #ifdef AF_INET6
      case AF_INET6:
  #endif
  #ifdef AF_UNIX
      case AF_UNIX:
  #endif
  #ifdef AF_UNSPEC
      case AF_UNSPEC:
  #endif
          break;
      default:
          ERR_raise(ERR_LIB_BIO, BIO_R_UNSUPPORTED_PROTOCOL_FAMILY);
          return 0;
      }
  
  #ifdef AF_UNIX
      if (family == AF_UNIX) {
          if (addrinfo_wrap(family, socktype, host, strlen(host), 0, res))
              return 1;
          else
              ERR_raise(ERR_LIB_BIO, ERR_R_MALLOC_FAILURE);
          return 0;
      }
  #endif
  
      if (BIO_sock_init() != 1)
          return 0;
  
      if (1) {
  #ifdef AI_PASSIVE
          int gai_ret = 0, old_ret = 0;
          struct addrinfo hints;
  
          memset(&hints, 0, sizeof(hints));
  
          hints.ai_family = family;
          hints.ai_socktype = socktype;
          hints.ai_protocol = protocol;
  # ifdef AI_ADDRCONFIG
  #  ifdef AF_UNSPEC
          if (host != NULL && family == AF_UNSPEC)
  #  endif
              hints.ai_flags |= AI_ADDRCONFIG;
  # endif
  
          if (lookup_type == BIO_LOOKUP_SERVER)
              hints.ai_flags |= AI_PASSIVE;
  
          /* Note that |res| SHOULD be a 'struct addrinfo **' thanks to
           * macro magic in bio_local.h
           */
  # if defined(AI_ADDRCONFIG) && defined(AI_NUMERICHOST)
        retry:
  # endif
          switch ((gai_ret = getaddrinfo(host, service, &hints, res))) {
  # ifdef EAI_SYSTEM
          case EAI_SYSTEM:
              ERR_raise_data(ERR_LIB_SYS, get_last_socket_error(),
                             "calling getaddrinfo()");
              ERR_raise(ERR_LIB_BIO, ERR_R_SYS_LIB);
              break;
  # endif
  # ifdef EAI_MEMORY
          case EAI_MEMORY:
              ERR_raise(ERR_LIB_BIO, ERR_R_MALLOC_FAILURE);
              break;
  # endif
          case 0:
              ret = 1;             /* Success */
              break;
          default:
  # if defined(AI_ADDRCONFIG) && defined(AI_NUMERICHOST)
              if (hints.ai_flags & AI_ADDRCONFIG) {
                  hints.ai_flags &= ~AI_ADDRCONFIG;
                  hints.ai_flags |= AI_NUMERICHOST;
                  old_ret = gai_ret;
                  goto retry;
              }
  # endif
              ERR_raise_data(ERR_LIB_BIO, ERR_R_SYS_LIB,
                             gai_strerror(old_ret ? old_ret : gai_ret));
              break;
          }
      } else {
  #endif
          const struct hostent *he;
  /*
   * Because struct hostent is defined for 32-bit pointers only with
   * VMS C, we need to make sure that '&he_fallback_address' and
   * '&he_fallback_addresses' are 32-bit pointers
   */
  #if defined(OPENSSL_SYS_VMS) && defined(__DECC)
  # pragma pointer_size save
  # pragma pointer_size 32
  #endif
          /* Windows doesn't seem to have in_addr_t */
  #ifdef OPENSSL_SYS_WINDOWS
          static uint32_t he_fallback_address;
          static const char *he_fallback_addresses[] =
              { (char *)&he_fallback_address, NULL };
  #else
          static in_addr_t he_fallback_address;
          static const char *he_fallback_addresses[] =
              { (char *)&he_fallback_address, NULL };
  #endif
          static const struct hostent he_fallback =
              { NULL, NULL, AF_INET, sizeof(he_fallback_address),
                (char **)&he_fallback_addresses };
  #if defined(OPENSSL_SYS_VMS) && defined(__DECC)
  # pragma pointer_size restore
  #endif
  
          struct servent *se;
          /* Apparently, on WIN64, s_proto and s_port have traded places... */
  #ifdef _WIN64
          struct servent se_fallback = { NULL, NULL, NULL, 0 };
  #else
          struct servent se_fallback = { NULL, NULL, 0, NULL };
  #endif
  
          if (!RUN_ONCE(&bio_lookup_init, do_bio_lookup_init)) {
              ERR_raise(ERR_LIB_BIO, ERR_R_MALLOC_FAILURE);
              ret = 0;
              goto err;
          }
  
          if (!CRYPTO_THREAD_write_lock(bio_lookup_lock)) {
              ret = 0;
              goto err;
          }
          he_fallback_address = INADDR_ANY;
          if (host == NULL) {
              he = &he_fallback;
              switch(lookup_type) {
              case BIO_LOOKUP_CLIENT:
                  he_fallback_address = INADDR_LOOPBACK;
                  break;
              case BIO_LOOKUP_SERVER:
                  he_fallback_address = INADDR_ANY;
                  break;
              default:
                  /* We forgot to handle a lookup type! */
                  assert("We forgot to handle a lookup type!" == NULL);
                  ERR_raise(ERR_LIB_BIO, ERR_R_INTERNAL_ERROR);
                  ret = 0;
                  goto err;
              }
          } else {
              he = gethostbyname(host);
  
              if (he == NULL) {
  #ifndef OPENSSL_SYS_WINDOWS
                  /*
                   * This might be misleading, because h_errno is used as if
                   * it was errno. To minimize mixup add 1000. Underlying
                   * reason for this is that hstrerror is declared obsolete,
                   * not to mention that a) h_errno is not always guaranteed
                   * to be meaningless; b) hstrerror can reside in yet another
                   * library, linking for sake of hstrerror is an overkill;
                   * c) this path is not executed on contemporary systems
                   * anyway [above getaddrinfo/gai_strerror is]. We just let
                   * system administrator figure this out...
                   */
  # if defined(OPENSSL_SYS_VXWORKS)
                  /* h_errno doesn't exist on VxWorks */
                  ERR_raise_data(ERR_LIB_SYS, 1000,
                                 "calling gethostbyname()");
  # else
                  ERR_raise_data(ERR_LIB_SYS, 1000 + h_errno,
                                 "calling gethostbyname()");
  # endif
  #else
                  ERR_raise_data(ERR_LIB_SYS, get_last_socket_error(),
                                 "calling gethostbyname()");
  #endif
                  ret = 0;
                  goto err;
              }
          }
  
          if (service == NULL) {
              se_fallback.s_port = 0;
              se_fallback.s_proto = NULL;
              se = &se_fallback;
          } else {
              char *endp = NULL;
              long portnum = strtol(service, &endp, 10);
  
  /*
   * Because struct servent is defined for 32-bit pointers only with
   * VMS C, we need to make sure that 'proto' is a 32-bit pointer.
   */
  #if defined(OPENSSL_SYS_VMS) && defined(__DECC)
  # pragma pointer_size save
  # pragma pointer_size 32
  #endif
              char *proto = NULL;
  #if defined(OPENSSL_SYS_VMS) && defined(__DECC)
  # pragma pointer_size restore
  #endif
  
              switch (socktype) {
              case SOCK_STREAM:
                  proto = "tcp";
                  break;
              case SOCK_DGRAM:
                  proto = "udp";
                  break;
              }
  
              if (endp != service && *endp == '\0'
                      && portnum > 0 && portnum < 65536) {
                  se_fallback.s_port = htons((unsigned short)portnum);
                  se_fallback.s_proto = proto;
                  se = &se_fallback;
              } else if (endp == service) {
                  se = getservbyname(service, proto);
  
                  if (se == NULL) {
                      ERR_raise_data(ERR_LIB_SYS, get_last_socket_error(),
                                     "calling getservbyname()");
                      goto err;
                  }
              } else {
                  ERR_raise(ERR_LIB_BIO, BIO_R_MALFORMED_HOST_OR_SERVICE);
                  goto err;
              }
          }
  
          *res = NULL;
  
          {
  /*
   * Because hostent::h_addr_list is an array of 32-bit pointers with VMS C,
   * we must make sure our iterator designates the same element type, hence
   * the pointer size dance.
   */
  #if defined(OPENSSL_SYS_VMS) && defined(__DECC)
  # pragma pointer_size save
  # pragma pointer_size 32
  #endif
              char **addrlistp;
  #if defined(OPENSSL_SYS_VMS) && defined(__DECC)
  # pragma pointer_size restore
  #endif
              size_t addresses;
              BIO_ADDRINFO *tmp_bai = NULL;
  
              /* The easiest way to create a linked list from an
                 array is to start from the back */
              for(addrlistp = he->h_addr_list; *addrlistp != NULL;
                  addrlistp++)
                  ;
  
              for(addresses = addrlistp - he->h_addr_list;
                  addrlistp--, addresses-- > 0; ) {
                  if (!addrinfo_wrap(he->h_addrtype, socktype,
                                     *addrlistp, he->h_length,
                                     se->s_port, &tmp_bai))
                      goto addrinfo_malloc_err;
                  tmp_bai->bai_next = *res;
                  *res = tmp_bai;
                  continue;
               addrinfo_malloc_err:
                  BIO_ADDRINFO_free(*res);
                  *res = NULL;
                  ERR_raise(ERR_LIB_BIO, ERR_R_MALLOC_FAILURE);
                  ret = 0;
                  goto err;
              }
  
              ret = 1;
          }
       err:
          CRYPTO_THREAD_unlock(bio_lookup_lock);
      }
  
      return ret;
  }
  
  #endif /* OPENSSL_NO_SOCK */
  