netsock2.c

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/*
 * Asterisk -- An open source telephony toolkit.
 *
 * Copyright (C) 2010, Digium, Inc.
 *
 * Viagénie <[email protected]>
 *
 * See http://www.asterisk.org for more information about
 * the Asterisk project. Please do not directly contact
 * any of the maintainers of this project for assistance;
 * the project provides a web site, mailing lists and IRC
 * channels for your use.
 *
 * This program is free software, distributed under the terms of
 * the GNU General Public License Version 2. See the LICENSE file
 * at the top of the source tree.
 */

/*! \file
 *
 * \brief Network socket handling
 *
 * \author Viagénie <[email protected]>
 */

/*** MODULEINFO
   <support_level>core</support_level>
 ***/

#include "asterisk.h"

#include "asterisk/config.h"
#include "asterisk/netsock2.h"
#include "asterisk/utils.h"
#include "asterisk/threadstorage.h"

int ast_sockaddr_ipv4_mapped(const struct ast_sockaddr *addr, struct ast_sockaddr *ast_mapped)
{
   const struct sockaddr_in6 *sin6;
   struct sockaddr_in sin4;

   if (!ast_sockaddr_is_ipv6(addr)) {
      return 0;
   }

   if (!ast_sockaddr_is_ipv4_mapped(addr)) {
      return 0;
   }

   sin6 = (const struct sockaddr_in6*)&addr->ss;

   memset(&sin4, 0, sizeof(sin4));
   sin4.sin_family = AF_INET;
   sin4.sin_port = sin6->sin6_port;
   sin4.sin_addr.s_addr = ((uint32_t *)&sin6->sin6_addr)[3];

   ast_sockaddr_from_sin(ast_mapped, &sin4);

   return 1;
}


AST_THREADSTORAGE(ast_sockaddr_stringify_buf);

char *ast_sockaddr_stringify_fmt(const struct ast_sockaddr *sa, int format)
{
   struct ast_sockaddr sa_ipv4;
   const struct ast_sockaddr *sa_tmp;
   char host[NI_MAXHOST];
   char port[NI_MAXSERV];
   struct ast_str *str;
   int e;
   static const size_t size = sizeof(host) - 1 + sizeof(port) - 1 + 4;


   if (ast_sockaddr_isnull(sa)) {
      return "(null)";
   }

   if (!(str = ast_str_thread_get(&ast_sockaddr_stringify_buf, size))) {
      return "";
   }

   if (ast_sockaddr_ipv4_mapped(sa, &sa_ipv4)) {
      sa_tmp = &sa_ipv4;
   } else {
      sa_tmp = sa;
   }

   if ((e = getnameinfo((struct sockaddr *)&sa_tmp->ss, sa_tmp->len,
              format & AST_SOCKADDR_STR_ADDR ? host : NULL,
              format & AST_SOCKADDR_STR_ADDR ? sizeof(host) : 0,
              format & AST_SOCKADDR_STR_PORT ? port : 0,
              format & AST_SOCKADDR_STR_PORT ? sizeof(port): 0,
              NI_NUMERICHOST | NI_NUMERICSERV))) {
      ast_log(LOG_ERROR, "getnameinfo(): %s\n", gai_strerror(e));
      return "";
   }

   if ((format & AST_SOCKADDR_STR_REMOTE) == AST_SOCKADDR_STR_REMOTE) {
      char *p;
      if (ast_sockaddr_is_ipv6_link_local(sa) && (p = strchr(host, '%'))) {
         *p = '\0';
      }
   }

   switch ((format & AST_SOCKADDR_STR_FORMAT_MASK))  {
   case AST_SOCKADDR_STR_DEFAULT:
      ast_str_set(&str, 0, sa_tmp->ss.ss_family == AF_INET6 ?
            "[%s]:%s" : "%s:%s", host, port);
      break;
   case AST_SOCKADDR_STR_ADDR:
      ast_str_set(&str, 0, "%s", host);
      break;
   case AST_SOCKADDR_STR_HOST:
      ast_str_set(&str, 0,
             sa_tmp->ss.ss_family == AF_INET6 ? "[%s]" : "%s", host);
      break;
   case AST_SOCKADDR_STR_PORT:
      ast_str_set(&str, 0, "%s", port);
      break;
   default:
      ast_log(LOG_ERROR, "Invalid format\n");
      return "";
   }

   return ast_str_buffer(str);
}

int ast_sockaddr_cidr_bits(const struct ast_sockaddr *sa)
{
   struct ast_sockaddr sa_ipv4;
   const struct ast_sockaddr *sa_tmp;
   int bits = 0;
   int bytes;
   int i;
   int j;
   char *addr;

   if (ast_sockaddr_isnull(sa)) {
      return 0;
   }

   if (ast_sockaddr_ipv4_mapped(sa, &sa_ipv4)) {
      sa_tmp = &sa_ipv4;
   } else {
      sa_tmp = sa;
   }

   bytes = sa_tmp->len;
   addr = ((struct sockaddr *)&sa_tmp->ss)->sa_data;

   for (i = 0; i < bytes ; ++i) {
      for (j = 0; j < 8; ++j) {
         if ((addr[i] >> j) & 1) {
            bits++;
         }
      }
   }

   return bits;
}

int ast_sockaddr_split_hostport(char *str, char **host, char **port, int flags)
{
   char *s = str;
   char *orig_str = str;/* Original string in case the port presence is incorrect. */
   char *host_end = NULL;/* Delay terminating the host in case the port presence is incorrect. */

   ast_debug(5, "Splitting '%s' into...\n", str);
   *host = NULL;
   *port = NULL;
   if (*s == '[') {
      *host = ++s;
      for (; *s && *s != ']'; ++s) {
      }
      if (*s == ']') {
         host_end = s;
         ++s;
      }
      if (*s == ':') {
         *port = s + 1;
      }
   } else {
      *host = s;
      for (; *s; ++s) {
         if (*s == ':') {
            if (*port) {
               *port = NULL;
               break;
            } else {
               *port = s;
            }
         }
      }
      if (*port) {
         host_end = *port;
         ++*port;
      }
   }

   switch (flags & PARSE_PORT_MASK) {
   case PARSE_PORT_IGNORE:
      *port = NULL;
      break;
   case PARSE_PORT_REQUIRE:
      if (*port == NULL) {
         ast_log(LOG_WARNING, "Port missing in %s\n", orig_str);
         return 0;
      }
      break;
   case PARSE_PORT_FORBID:
      if (*port != NULL) {
         ast_log(LOG_WARNING, "Port disallowed in %s\n", orig_str);
         return 0;
      }
      break;
   }

   /* Can terminate the host string now if needed. */
   if (host_end) {
      *host_end = '\0';
   }
   ast_debug(5, "...host '%s' and port '%s'.\n", *host, *port ? *port : "");
   return 1;
}



int ast_sockaddr_parse(struct ast_sockaddr *addr, const char *str, int flags)
{
   struct addrinfo hints;
   struct addrinfo   *res;
   char *s;
   char *host;
   char *port;
   int   e;

   s = ast_strdupa(str);
   if (!ast_sockaddr_split_hostport(s, &host, &port, flags)) {
      return 0;
   }

   memset(&hints, 0, sizeof(hints));
   /* Hint to get only one entry from getaddrinfo */
   hints.ai_socktype = SOCK_DGRAM;

#ifdef AI_NUMERICSERV
   hints.ai_flags = AI_NUMERICHOST | AI_NUMERICSERV;
#else
   hints.ai_flags = AI_NUMERICHOST;
#endif
   if ((e = getaddrinfo(host, port, &hints, &res))) {
      if (e != EAI_NONAME) { /* if this was just a host name rather than a ip address, don't print error */
         ast_log(LOG_ERROR, "getaddrinfo(\"%s\", \"%s\", ...): %s\n",
            host, S_OR(port, "(null)"), gai_strerror(e));
      }
      return 0;
   }

   /*
    * I don't see how this could be possible since we're not resolving host
    * names. But let's be careful...
    */
   if (res->ai_next != NULL) {
      ast_log(LOG_WARNING, "getaddrinfo() returned multiple "
         "addresses. Ignoring all but the first.\n");
   }

   if (addr) {
      addr->len = res->ai_addrlen;
      memcpy(&addr->ss, res->ai_addr, addr->len);
   }

   freeaddrinfo(res);

   return 1;
}

int ast_sockaddr_resolve(struct ast_sockaddr **addrs, const char *str,
          int flags, int family)
{
   struct addrinfo hints, *res, *ai;
   char *s, *host, *port;
   int   e, i, res_cnt;

   if (!str) {
      *addrs = NULL;
      return 0;
   }

   s = ast_strdupa(str);
   if (!ast_sockaddr_split_hostport(s, &host, &port, flags)) {
      *addrs = NULL;
      return 0;
   }

   memset(&hints, 0, sizeof(hints));
   hints.ai_family = family;
   hints.ai_socktype = SOCK_DGRAM;

   if ((e = getaddrinfo(host, port, &hints, &res))) {
      ast_log(LOG_ERROR, "getaddrinfo(\"%s\", \"%s\", ...): %s\n",
         host, S_OR(port, "(null)"), gai_strerror(e));
      *addrs = NULL;
      return 0;
   }

   res_cnt = 0;
   for (ai = res; ai; ai = ai->ai_next) {
      res_cnt++;
   }

   if (res_cnt == 0) {
      *addrs = NULL;
      goto cleanup;
   }

   if ((*addrs = ast_malloc(res_cnt * sizeof(struct ast_sockaddr))) == NULL) {
      res_cnt = 0;
      goto cleanup;
   }

   i = 0;
   for (ai = res; ai; ai = ai->ai_next) {
      (*addrs)[i].len = ai->ai_addrlen;
      memcpy(&(*addrs)[i].ss, ai->ai_addr, ai->ai_addrlen);
      ++i;
   }

cleanup:
   freeaddrinfo(res);
   return res_cnt;
}

/*! \brief Pulls first resolved address and returns it */
int ast_sockaddr_resolve_first_af(struct ast_sockaddr *addr,
                  const char* name, int flag, int family)
{
   struct ast_sockaddr *addrs;
   int addrs_cnt;

   addrs_cnt = ast_sockaddr_resolve(&addrs, name, flag, family);
   if (addrs_cnt <= 0) {
      return 1;
   }
   if (addrs_cnt > 1) {
      ast_debug(1, "Multiple addresses resolving %s, using the first one only\n", name);
   }

   ast_sockaddr_copy(addr, &addrs[0]);

   ast_free(addrs);
   return 0;
}

int ast_sockaddr_apply_netmask(const struct ast_sockaddr *addr, const struct ast_sockaddr *netmask,
      struct ast_sockaddr *result)
{
   int res = 0;

   if (ast_sockaddr_is_ipv4(addr)) {
      struct sockaddr_in result4 = { 0, };
      struct sockaddr_in *addr4 = (struct sockaddr_in *) &addr->ss;
      struct sockaddr_in *mask4 = (struct sockaddr_in *) &netmask->ss;
      result4.sin_family = AF_INET;
      result4.sin_addr.s_addr = addr4->sin_addr.s_addr & mask4->sin_addr.s_addr;
      ast_sockaddr_from_sin(result, &result4);
   } else if (ast_sockaddr_is_ipv6(addr)) {
      struct sockaddr_in6 result6 = { 0, };
      struct sockaddr_in6 *addr6 = (struct sockaddr_in6 *) &addr->ss;
      struct sockaddr_in6 *mask6 = (struct sockaddr_in6 *) &netmask->ss;
      int i;
      result6.sin6_family = AF_INET6;
      for (i = 0; i < 4; ++i) {
         V6_WORD(&result6, i) = V6_WORD(addr6, i) & V6_WORD(mask6, i);
      }
      memcpy(&result->ss, &result6, sizeof(result6));
      result->len = sizeof(result6);
   } else {
      /* Unsupported address scheme */
      res = -1;
   }

   return res;
}

int ast_sockaddr_cmp(const struct ast_sockaddr *a, const struct ast_sockaddr *b)
{
   const struct ast_sockaddr *a_tmp, *b_tmp;
   struct ast_sockaddr ipv4_mapped;

   a_tmp = a;
   b_tmp = b;

   if (a_tmp->len != b_tmp->len) {
      if (ast_sockaddr_ipv4_mapped(a, &ipv4_mapped)) {
         a_tmp = &ipv4_mapped;
      } else if (ast_sockaddr_ipv4_mapped(b, &ipv4_mapped)) {
         b_tmp = &ipv4_mapped;
      }
   }

   if (a_tmp->len < b_tmp->len) {
      return -1;
   } else if (a_tmp->len > b_tmp->len) {
      return 1;
   }

   return memcmp(&a_tmp->ss, &b_tmp->ss, a_tmp->len);
}

int ast_sockaddr_cmp_addr(const struct ast_sockaddr *a, const struct ast_sockaddr *b)
{
   const struct ast_sockaddr *a_tmp, *b_tmp;
   struct ast_sockaddr ipv4_mapped;
   const struct in_addr *ip4a, *ip4b;
   const struct in6_addr *ip6a, *ip6b;
   int ret = -1;

   a_tmp = a;
   b_tmp = b;

   if (a_tmp->len != b_tmp->len) {
      if (ast_sockaddr_ipv4_mapped(a, &ipv4_mapped)) {
         a_tmp = &ipv4_mapped;
      } else if (ast_sockaddr_ipv4_mapped(b, &ipv4_mapped)) {
         b_tmp = &ipv4_mapped;
      }
   }

   if (a->len < b->len) {
      ret = -1;
   } else if (a->len > b->len) {
      ret = 1;
   }

   switch (a_tmp->ss.ss_family) {
   case AF_INET:
      ip4a = &((const struct sockaddr_in*)&a_tmp->ss)->sin_addr;
      ip4b = &((const struct sockaddr_in*)&b_tmp->ss)->sin_addr;
      ret = memcmp(ip4a, ip4b, sizeof(*ip4a));
      break;
   case AF_INET6:
      ip6a = &((const struct sockaddr_in6*)&a_tmp->ss)->sin6_addr;
      ip6b = &((const struct sockaddr_in6*)&b_tmp->ss)->sin6_addr;
      ret = memcmp(ip6a, ip6b, sizeof(*ip6a));
      break;
   }
   return ret;
}

uint16_t _ast_sockaddr_port(const struct ast_sockaddr *addr, const char *file, int line, const char *func)
{
   /*
    * Test addr->len first to be tolerant of an ast_sockaddr_setnull()
    * addr.  In that case addr->len might be the only value initialized.
    */
   if (addr->len == sizeof(struct sockaddr_in)
      && addr->ss.ss_family == AF_INET) {
      return ntohs(((struct sockaddr_in *)&addr->ss)->sin_port);
   }
   if (addr->len == sizeof(struct sockaddr_in6)
      && addr->ss.ss_family == AF_INET6) {
      return ntohs(((struct sockaddr_in6 *)&addr->ss)->sin6_port);
   }
   if (DEBUG_ATLEAST(1)) {
      ast_log(__LOG_DEBUG, file, line, func, "Not an IPv4 nor IPv6 address, cannot get port.\n");
   }
   return 0;
}

void _ast_sockaddr_set_port(struct ast_sockaddr *addr, uint16_t port, const char *file, int line, const char *func)
{
   /*
    * Test addr->len first to be tolerant of an ast_sockaddr_setnull()
    * addr.  In that case addr->len might be the only value initialized.
    */
   if (addr->len == sizeof(struct sockaddr_in)
      && addr->ss.ss_family == AF_INET) {
      ((struct sockaddr_in *)&addr->ss)->sin_port = htons(port);
   } else if (addr->len == sizeof(struct sockaddr_in6)
      && addr->ss.ss_family == AF_INET6) {
      ((struct sockaddr_in6 *)&addr->ss)->sin6_port = htons(port);
   } else if (DEBUG_ATLEAST(1)) {
      ast_log(__LOG_DEBUG, file, line, func,
         "Not an IPv4 nor IPv6 address, cannot set port.\n");
   }
}

uint32_t ast_sockaddr_ipv4(const struct ast_sockaddr *addr)
{
   const struct sockaddr_in *sin = (struct sockaddr_in *)&addr->ss;
   return ntohl(sin->sin_addr.s_addr);
}

int ast_sockaddr_is_ipv4(const struct ast_sockaddr *addr)
{
   /*
    * Test addr->len first to be tolerant of an ast_sockaddr_setnull()
    * addr.  In that case addr->len might be the only value initialized.
    */
   return addr->len == sizeof(struct sockaddr_in)
      && addr->ss.ss_family == AF_INET;
}

int ast_sockaddr_is_ipv4_mapped(const struct ast_sockaddr *addr)
{
   const struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)&addr->ss;
   return addr->len && IN6_IS_ADDR_V4MAPPED(&sin6->sin6_addr);
}

int ast_sockaddr_is_ipv4_multicast(const struct ast_sockaddr *addr)
{
   return ((ast_sockaddr_ipv4(addr) & 0xf0000000) == 0xe0000000);
}

int ast_sockaddr_is_ipv6_link_local(const struct ast_sockaddr *addr)
{
   const struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)&addr->ss;
   return ast_sockaddr_is_ipv6(addr) && IN6_IS_ADDR_LINKLOCAL(&sin6->sin6_addr);
}

int ast_sockaddr_is_ipv6(const struct ast_sockaddr *addr)
{
   /*
    * Test addr->len first to be tolerant of an ast_sockaddr_setnull()
    * addr.  In that case addr->len might be the only value initialized.
    */
   return addr->len == sizeof(struct sockaddr_in6)
      && addr->ss.ss_family == AF_INET6;
}

int ast_sockaddr_is_any(const struct ast_sockaddr *addr)
{
   union {
      struct sockaddr_storage ss;
      struct sockaddr_in sin;
      struct sockaddr_in6 sin6;
   } tmp_addr = {
      .ss = addr->ss,
   };

   return (ast_sockaddr_is_ipv4(addr) && (tmp_addr.sin.sin_addr.s_addr == INADDR_ANY)) ||
       (ast_sockaddr_is_ipv6(addr) && IN6_IS_ADDR_UNSPECIFIED(&tmp_addr.sin6.sin6_addr));
}

int ast_sockaddr_hash(const struct ast_sockaddr *addr)
{
   /*
    * For IPv4, return the IP address as-is. For IPv6, return the last 32
    * bits.
    */
   switch (addr->ss.ss_family) {
   case AF_INET:
      return ((const struct sockaddr_in *)&addr->ss)->sin_addr.s_addr;
   case AF_INET6:
      return ((uint32_t *)&((const struct sockaddr_in6 *)&addr->ss)->sin6_addr)[3];
   default:
      ast_log(LOG_ERROR, "Unknown address family '%d'.\n",
         addr->ss.ss_family);
      return 0;
   }
}

const char *ast_transport2str(enum ast_transport transport)
{
   switch (transport) {
   case AST_TRANSPORT_TLS:
      return "TLS";
   case AST_TRANSPORT_UDP:
      return "UDP";
   case AST_TRANSPORT_TCP:
      return "TCP";
   case AST_TRANSPORT_WS:
      return "WS";
   case AST_TRANSPORT_WSS:
      return "WSS";
   }

   return "Undefined";
}

int ast_accept(int sockfd, struct ast_sockaddr *addr)
{
   addr->len = sizeof(addr->ss);
   return accept(sockfd, (struct sockaddr *)&addr->ss, &addr->len);
}

int ast_bind(int sockfd, const struct ast_sockaddr *addr)
{
   return bind(sockfd, (const struct sockaddr *)&addr->ss, addr->len);
}

int ast_connect(int sockfd, const struct ast_sockaddr *addr)
{
   return connect(sockfd, (const struct sockaddr *)&addr->ss, addr->len);
}

int ast_getsockname(int sockfd, struct ast_sockaddr *addr)
{
   addr->len = sizeof(addr->ss);
   return getsockname(sockfd, (struct sockaddr *)&addr->ss, &addr->len);
}

ssize_t ast_recvfrom(int sockfd, void *buf, size_t len, int flags,
           struct ast_sockaddr *src_addr)
{
   src_addr->len = sizeof(src_addr->ss);
   return recvfrom(sockfd, buf, len, flags,
         (struct sockaddr *)&src_addr->ss, &src_addr->len);
}

ssize_t ast_sendto(int sockfd, const void *buf, size_t len, int flags,
         const struct ast_sockaddr *dest_addr)
{
   return sendto(sockfd, buf, len, flags,
            (const struct sockaddr *)&dest_addr->ss, dest_addr->len);
}

int ast_set_qos(int sockfd, int tos, int cos, const char *desc)
{
   int res = 0;
   int set_tos;
   int set_tclass;
   struct ast_sockaddr addr;

   /* If the sock address is IPv6, the TCLASS field must be set. */
   set_tclass = !ast_getsockname(sockfd, &addr) && ast_sockaddr_is_ipv6(&addr) ? 1 : 0;

   /* If the sock address is IPv4 or (IPv6 set to any address [::]) set TOS bits */
   set_tos = (!set_tclass || (set_tclass && ast_sockaddr_is_any(&addr))) ? 1 : 0;

   if (set_tos) {
      if ((res = setsockopt(sockfd, IPPROTO_IP, IP_TOS, &tos, sizeof(tos)))) {
         ast_log(LOG_WARNING, "Unable to set %s DSCP TOS value to %d (may be you have no "
            "root privileges): %s\n", desc, tos, strerror(errno));
      } else if (tos) {
         ast_verb(2, "Using %s TOS bits %d\n", desc, tos);
      }
   }

#if defined(IPV6_TCLASS) && defined(IPPROTO_IPV6)
   if (set_tclass) {
      if (!ast_getsockname(sockfd, &addr) && ast_sockaddr_is_ipv6(&addr)) {
         if ((res = setsockopt(sockfd, IPPROTO_IPV6, IPV6_TCLASS, &tos, sizeof(tos)))) {
            ast_log(LOG_WARNING, "Unable to set %s DSCP TCLASS field to %d (may be you have no "
               "root privileges): %s\n", desc, tos, strerror(errno));
         } else if (tos) {
            ast_verb(2, "Using %s TOS bits %d in TCLASS field.\n", desc, tos);
         }
      }
   }
#endif

#ifdef linux
   if (setsockopt(sockfd, SOL_SOCKET, SO_PRIORITY, &cos, sizeof(cos))) {
      ast_log(LOG_WARNING, "Unable to set %s CoS to %d: %s\n", desc, cos,
         strerror(errno));
   } else if (cos) {
      ast_verb(2, "Using %s CoS mark %d\n", desc, cos);
   }
#endif

   return res;
}

int _ast_sockaddr_to_sin(const struct ast_sockaddr *addr,
         struct sockaddr_in *sin, const char *file, int line, const char *func)
{
   if (ast_sockaddr_isnull(addr)) {
      memset(sin, 0, sizeof(*sin));
      return 1;
   }

   if (addr->len != sizeof(*sin)) {
      ast_log(__LOG_ERROR, file, line, func, "Bad address cast to IPv4\n");
      return 0;
   }

   if (addr->ss.ss_family != AF_INET && DEBUG_ATLEAST(1)) {
      ast_log(__LOG_DEBUG, file, line, func, "Address family is not AF_INET\n");
   }

   *sin = *(struct sockaddr_in *)&addr->ss;
   return 1;
}

void _ast_sockaddr_from_sin(struct ast_sockaddr *addr, const struct sockaddr_in *sin,
      const char *file, int line, const char *func)
{
   memcpy(&addr->ss, sin, sizeof(*sin));

   if (addr->ss.ss_family != AF_INET && DEBUG_ATLEAST(1)) {
      ast_log(__LOG_DEBUG, file, line, func, "Address family is not AF_INET\n");
   }

   addr->len = sizeof(*sin);
}