extl_dtls.c

mediastreamer2是开源的网络传输媒体流的库

      len = sizeof (ai_addr);
      res = getsockname (sock, (struct sockaddr *) &ai_addr, &len);
      if (res != 0)
        {
          OSIP_TRACE (osip_trace
                      (__FILE__, __LINE__, OSIP_ERROR, NULL,
                       "eXosip: Cannot get socket name (%s)\n", strerror (errno)));
          memcpy (&ai_addr, curinfo->ai_addr, curinfo->ai_addrlen);
        }

      if (eXtl_dtls.proto_num == IPPROTO_TCP)
        {
          res = listen (sock, SOMAXCONN);
          if (res < 0)
            {
              OSIP_TRACE (osip_trace
                          (__FILE__, __LINE__, OSIP_ERROR, NULL,
                           "eXosip: Cannot bind socket node:%s family:%d %s\n",
                           eXtl_dtls.proto_ifs, curinfo->ai_family,
                           strerror (errno)));
              close (sock);
              sock = -1;
              continue;
            }
        }

      break;
    }

  eXosip_freeaddrinfo (addrinfo);

  if (sock < 0)
    {
      OSIP_TRACE (osip_trace
                  (__FILE__, __LINE__, OSIP_ERROR, NULL,
                   "eXosip: Cannot bind on port: %i\n", eXtl_dtls.proto_port));
      return -1;
    }

  dtls_socket = sock;

  if (eXtl_dtls.proto_port == 0)
    {
      /* get port number from socket */
      if (eXtl_dtls.proto_family == AF_INET)
        eXtl_dtls.proto_port = ntohs (((struct sockaddr_in *) &ai_addr)->sin_port);
      else
        eXtl_dtls.proto_port =
          ntohs (((struct sockaddr_in6 *) &ai_addr)->sin6_port);
      OSIP_TRACE (osip_trace
                  (__FILE__, __LINE__, OSIP_INFO1, NULL,
                   "eXosip: Binding on port %i!\n", eXtl_dtls.proto_port));
    }

  snprintf (dtls_firewall_port, sizeof (dtls_firewall_port), "%i",
            eXtl_dtls.proto_port);
  return OSIP_SUCCESS;
}

#define EXOSIP_AS_A_SERVER 1
#define EXOSIP_AS_A_CLIENT 2

static int
dtls_tl_set_fdset (fd_set * osip_fdset, int *fd_max)
{
  if (dtls_socket <= 0)
    return -1;

  eXFD_SET (dtls_socket, osip_fdset);

  if (dtls_socket > *fd_max)
    *fd_max = dtls_socket;

  return OSIP_SUCCESS;
}

static int
dtls_tl_read_message (fd_set * osip_fdset)
{
  char *enc_buf;
  char *dec_buf;
  int i;
  int enc_buf_len;

  if (dtls_socket <= 0)
    return -1;

  if (FD_ISSET (dtls_socket, osip_fdset))
    {
      struct sockaddr_storage sa;

#ifdef __linux
      socklen_t slen;
#else
      int slen;
#endif
      if (eXtl_dtls.proto_family == AF_INET)
        slen = sizeof (struct sockaddr_in);
      else
        slen = sizeof (struct sockaddr_in6);

      enc_buf = (char *) osip_malloc (SIP_MESSAGE_MAX_LENGTH * sizeof (char) + 1);
      if (enc_buf == NULL)
        return OSIP_NOMEM;

      enc_buf_len = recvfrom (dtls_socket, enc_buf,
                              SIP_MESSAGE_MAX_LENGTH, 0,
                              (struct sockaddr *) &sa, &slen);

      if (enc_buf_len > 5)
        {
          char src6host[NI_MAXHOST];
          int recvport = 0;
          int err;

          BIO *rbio;
          struct socket_tab *socket_tab_used = NULL;
          int pos;

          osip_strncpy (enc_buf + enc_buf_len, "\0", 1);
          OSIP_TRACE (osip_trace (__FILE__, __LINE__, OSIP_INFO1, NULL,
                                  "Received message: \n%s\n", enc_buf));

          memset (src6host, 0, sizeof (src6host));

          if (eXtl_dtls.proto_family == AF_INET)
            recvport = ntohs (((struct sockaddr_in *) &sa)->sin_port);
          else
            recvport = ntohs (((struct sockaddr_in6 *) &sa)->sin6_port);

#if defined(__arc__)
          {
            struct sockaddr_in *fromsa = (struct sockaddr_in *) &sa;
            char *tmp;
            tmp = inet_ntoa (fromsa->sin_addr);
            if (tmp == NULL)
              {
                OSIP_TRACE (osip_trace
                            (__FILE__, __LINE__, OSIP_ERROR, NULL,
                             "Message received from: NULL:%i inet_ntoa failure\n",
                             recvport));
            } else
              {
                snprintf (src6host, sizeof (src6host), "%s", tmp);
                OSIP_TRACE (osip_trace
                            (__FILE__, __LINE__, OSIP_INFO1, NULL,
                             "Message received from: %s:%i\n", src6host,
                             recvport));
              }
          }
#else
          err = getnameinfo ((struct sockaddr *) &sa, slen,
                             src6host, NI_MAXHOST, NULL, 0, NI_NUMERICHOST);

          if (err != 0)
            {
              OSIP_TRACE (osip_trace
                          (__FILE__, __LINE__, OSIP_ERROR, NULL,
                           "Message received from: NULL:%i getnameinfo failure\n",
                           recvport));
              snprintf (src6host, sizeof (src6host), "127.0.0.1");
          } else
            {
              OSIP_TRACE (osip_trace
                          (__FILE__, __LINE__, OSIP_INFO1, NULL,
                           "Message received from: %s:%i\n", src6host, recvport));
            }
#endif

          OSIP_TRACE (osip_trace
                      (__FILE__, __LINE__, OSIP_INFO1, NULL,
                       "Message received from: %s:%i\n", src6host, recvport));

          for (pos = 0; pos < EXOSIP_MAX_SOCKETS; pos++)
            {
              if (dtls_socket_tab[pos].ssl_conn != NULL)
                {
                  if (dtls_socket_tab[pos].remote_port == recvport &&
                      (strcmp (dtls_socket_tab[pos].remote_ip, src6host) == 0))
                    {
                      socket_tab_used = &dtls_socket_tab[pos];
                      break;
                    }
                }
            }

          if (socket_tab_used == NULL)
            {
              for (pos = 0; pos < EXOSIP_MAX_SOCKETS; pos++)
                {
                  if (dtls_socket_tab[pos].ssl_conn == NULL)
                    {
                      /* should accept this connection? */
                      break;
                    }
                }

              OSIP_TRACE (osip_trace (__FILE__, __LINE__, OSIP_INFO3, NULL,
                                      "creating DTLS socket at index: %i\n", pos));
              if (pos < 0)
                {
                  /* delete an old one! */
                  pos = 0;
                  if (dtls_socket_tab[pos].ssl_conn != NULL)
                    {
                      shutdown_free_client_dtls (pos);
                      shutdown_free_server_dtls (pos);
                    }

                  memset (&dtls_socket_tab[pos], 0, sizeof (struct socket_tab));
                }
            }

          if (dtls_socket_tab[pos].ssl_conn == NULL)
            {
              BIO *wbio;
              if (!SSL_CTX_check_private_key (server_ctx))
                {
                  OSIP_TRACE (osip_trace
                              (__FILE__, __LINE__, OSIP_ERROR, NULL,
                               "SSL CTX private key check error\n"));
                  osip_free (enc_buf);
                  return -1;
                }

              /* behave as a server: */
              dtls_socket_tab[pos].ssl_conn = SSL_new (server_ctx);
              if (dtls_socket_tab[pos].ssl_conn == NULL)
                {
                  OSIP_TRACE (osip_trace
                              (__FILE__, __LINE__, OSIP_ERROR, NULL,
                               "SSL_new error\n"));
                  osip_free (enc_buf);
                  return -1;
                }

              /* No MTU query */
#ifdef	SSL_OP_NO_QUERY_MTU
              SSL_set_options (dtls_socket_tab[pos].ssl_conn, SSL_OP_NO_QUERY_MTU);
              SSL_set_mtu (dtls_socket_tab[pos].ssl_conn, 2000);
#endif
              /* MTU query */
              /* BIO_ctrl(sbio, BIO_CTRL_DGRAM_MTU_DISCOVER, 0, NULL); */
#ifdef	SSL_OP_COOKIE_EXCHANGE
              SSL_set_options (dtls_socket_tab[pos].ssl_conn,
                               SSL_OP_COOKIE_EXCHANGE);
#endif
              wbio = BIO_new_dgram (dtls_socket, BIO_NOCLOSE);
              BIO_dgram_set_peer (wbio, &sa);
              SSL_set_bio (dtls_socket_tab[pos].ssl_conn, NULL, wbio);

              SSL_set_accept_state (dtls_socket_tab[pos].ssl_conn);

              dtls_socket_tab[pos].ssl_state = 0;
              dtls_socket_tab[pos].ssl_type = EXOSIP_AS_A_SERVER;

              osip_strncpy (dtls_socket_tab[pos].remote_ip, src6host,
                            sizeof (dtls_socket_tab[pos].remote_ip) - 1);
              dtls_socket_tab[pos].remote_port = recvport;

              OSIP_TRACE (osip_trace (__FILE__, __LINE__, OSIP_INFO1, NULL,
                                      "New DTLS connection accepted\n"));

            }

          dec_buf =
            (char *) osip_malloc (SIP_MESSAGE_MAX_LENGTH * sizeof (char) + 1);
          if (dec_buf == NULL)
            {
              OSIP_TRACE (osip_trace
                          (__FILE__, __LINE__, OSIP_ERROR, NULL,
                           "Allocation error\n"));
              osip_free (enc_buf);
              return OSIP_NOMEM;
            }
          rbio = BIO_new_mem_buf (enc_buf, enc_buf_len);
          BIO_set_mem_eof_return (rbio, -1);

          dtls_socket_tab[pos].ssl_conn->rbio = rbio;

          i =
            SSL_read (dtls_socket_tab[pos].ssl_conn, dec_buf,
                      SIP_MESSAGE_MAX_LENGTH);
          /* done with the rbio */
          BIO_free (dtls_socket_tab[pos].ssl_conn->rbio);
          dtls_socket_tab[pos].ssl_conn->rbio = BIO_new (BIO_s_mem ());

          if (i > 5)
            {
              osip_strncpy (dec_buf + i, "\0", 1);

              _eXosip_handle_incoming_message (dec_buf, i, dtls_socket, src6host,
                                               recvport);

            }
#ifndef MINISIZE
          else if (i <= 0)
            {
              err = SSL_get_error (dtls_socket_tab[pos].ssl_conn, i);
              print_ssl_error (err);
              if (err == SSL_ERROR_SYSCALL)
                {
                  OSIP_TRACE (osip_trace
                              (__FILE__, __LINE__, OSIP_WARNING,
                               NULL, "DTLS SYSCALL on SSL_read\n"));
              } else if (err == SSL_ERROR_SSL || err == SSL_ERROR_ZERO_RETURN)
                {
                  OSIP_TRACE (osip_trace
                              (__FILE__, __LINE__, OSIP_WARNING,
                               NULL, "DTLS closed\n"));

                  shutdown_free_client_dtls (pos);
                  shutdown_free_server_dtls (pos);

                  memset (&(dtls_socket_tab[pos]), 0,
                          sizeof (dtls_socket_tab[pos]));
                }
          } else
            {
              OSIP_TRACE (osip_trace (__FILE__, __LINE__, OSIP_INFO1, NULL,
                                      "Dummy SIP message received\n"));
            }
#endif

          osip_free (dec_buf);
          osip_free (enc_buf);

        }
    }

  return OSIP_SUCCESS;
}

static int
eXtl_update_local_target (osip_message_t * req)
{
  int pos = 0;

  if (dtls_firewall_ip != '\0')
    {

      while (!osip_list_eol (&req->contacts, pos))
        {
          osip_contact_t *co;

          co = (osip_contact_t *) osip_list_get (&req->contacts, pos);
          pos++;
          if (co != NULL && co->url != NULL && co->url->host != NULL
              && 0 == osip_strcasecmp (co->url->host, dtls_firewall_ip))
            {
              if (co->url->port == NULL &&
                  0 != osip_strcasecmp (dtls_firewall_port, "5061"))
                {
                  co->url->port = osip_strdup (dtls_firewall_port);
              } else if (co->url->port != NULL &&
                         0 != osip_strcasecmp (dtls_firewall_port, co->url->port))
                {
                  osip_free (co->url->port);
                  co->url->port = osip_strdup (dtls_firewall_port);
                }
            }
        }
    }

  return OSIP_SUCCESS;
}

#ifndef INET6_ADDRSTRLEN
#define INET6_ADDRSTRLEN 46
#endif

static int
dtls_tl_send_message (osip_transaction_t * tr, osip_message_t * sip, char *host,