コード例 #1
0
ファイル: ice.c プロジェクト: daviad/MeadTest
uint32_t stun_usage_ice_conncheck_priority (const StunMessage *msg)
{
    uint32_t value;
    
    if (stun_message_find32 (msg, STUN_ATTRIBUTE_PRIORITY, &value)
        != STUN_MESSAGE_RETURN_SUCCESS)
        return 0;
    return value;
}
コード例 #2
0
ファイル: turn.c プロジェクト: roxlu/krx_rtc
StunUsageTurnReturn stun_usage_turn_refresh_process (StunMessage *msg,
    uint32_t *lifetime, StunUsageTurnCompatibility compatibility)
{
  int code = -1;
  StunUsageTurnReturn ret = STUN_USAGE_TURN_RETURN_RELAY_SUCCESS;

  if (compatibility == STUN_USAGE_TURN_COMPATIBILITY_DRAFT9 ||
      compatibility == STUN_USAGE_TURN_COMPATIBILITY_RFC5766) {
    if (stun_message_get_method (msg) != STUN_REFRESH)
      return STUN_USAGE_TURN_RETURN_INVALID;
  } else {
    if (stun_message_get_method (msg) != STUN_ALLOCATE)
      return STUN_USAGE_TURN_RETURN_INVALID;
  }

  switch (stun_message_get_class (msg))
  {
    case STUN_REQUEST:
    case STUN_INDICATION:
      return STUN_USAGE_TURN_RETURN_INVALID;

    case STUN_RESPONSE:
      break;

    case STUN_ERROR:
      if (stun_message_find_error (msg, &code) != STUN_MESSAGE_RETURN_SUCCESS) {
        /* missing ERROR-CODE: ignore message */
        return STUN_USAGE_TURN_RETURN_INVALID;
      }

      return STUN_USAGE_TURN_RETURN_ERROR;

    default:
      /* Fall through. */
      break;
  }

  stun_message_find32 (msg, STUN_ATTRIBUTE_LIFETIME, lifetime);

  stun_debug ("TURN Refresh successful!\n");
  return ret;

}
コード例 #3
0
ファイル: stunagent.c プロジェクト: GYGit/oneteam
StunValidationStatus stun_agent_validate (StunAgent *agent, StunMessage *msg,
    const uint8_t *buffer, size_t buffer_len,
    StunMessageIntegrityValidate validater, void * validater_data)
{
  StunTransactionId msg_id;
  uint32_t fpr;
  uint32_t crc32;
  int len;
  uint8_t *username = NULL;
  uint16_t username_len;
  uint8_t *key = NULL;
  size_t key_len;
  uint8_t *hash;
  uint8_t sha[20];
  uint16_t hlen;
  int sent_id_idx = -1;
  uint16_t unknown;
  int error_code;
  int ignore_credentials = 0;
  uint8_t long_term_key[16];
  bool long_term_key_valid = FALSE;

  len = stun_message_validate_buffer_length (buffer, buffer_len);
  if (len == STUN_MESSAGE_BUFFER_INVALID) {
    return STUN_VALIDATION_NOT_STUN;
  } else if (len == STUN_MESSAGE_BUFFER_INCOMPLETE) {
    return STUN_VALIDATION_INCOMPLETE_STUN;
  } else if (len != (int) buffer_len) {
    return STUN_VALIDATION_NOT_STUN;
  }

  msg->buffer = (uint8_t *) buffer;
  msg->buffer_len = buffer_len;
  msg->agent = agent;
  msg->key = NULL;
  msg->key_len = 0;
  msg->long_term_valid = FALSE;

  /* TODO: reject it or not ? */
  if ((agent->compatibility == STUN_COMPATIBILITY_RFC5389 ||
          agent->compatibility == STUN_COMPATIBILITY_WLM2009) &&
      !stun_message_has_cookie (msg)) {
      stun_debug ("STUN demux error: no cookie!\n");
      return STUN_VALIDATION_BAD_REQUEST;
  }

  if ((agent->compatibility == STUN_COMPATIBILITY_RFC5389 ||
          agent->compatibility == STUN_COMPATIBILITY_WLM2009) &&
      agent->usage_flags & STUN_AGENT_USAGE_USE_FINGERPRINT) {
    /* Looks for FINGERPRINT */
    if (stun_message_find32 (msg, STUN_ATTRIBUTE_FINGERPRINT, &fpr) !=
        STUN_MESSAGE_RETURN_SUCCESS) {
      stun_debug ("STUN demux error: no FINGERPRINT attribute!\n");
      return STUN_VALIDATION_BAD_REQUEST;
    }
    /* Checks FINGERPRINT */
    crc32 = stun_fingerprint (msg->buffer, stun_message_length (msg),
        agent->compatibility == STUN_COMPATIBILITY_WLM2009);
    fpr = ntohl (fpr);
    if (fpr != crc32) {
      stun_debug ("STUN demux error: bad fingerprint: 0x%08x,"
          " expected: 0x%08x!\n", fpr, crc32);
      return STUN_VALIDATION_BAD_REQUEST;
    }

    stun_debug ("STUN demux: OK!\n");
  }

  if (stun_message_get_class (msg) == STUN_RESPONSE ||
      stun_message_get_class (msg) == STUN_ERROR) {
    stun_message_id (msg, msg_id);
    for (sent_id_idx = 0; sent_id_idx < STUN_AGENT_MAX_SAVED_IDS; sent_id_idx++) {
      if (agent->sent_ids[sent_id_idx].valid == TRUE &&
          agent->sent_ids[sent_id_idx].method == stun_message_get_method (msg) &&
          memcmp (msg_id, agent->sent_ids[sent_id_idx].id,
              sizeof(StunTransactionId)) == 0) {

        key = agent->sent_ids[sent_id_idx].key;
        key_len = agent->sent_ids[sent_id_idx].key_len;
        memcpy (long_term_key, agent->sent_ids[sent_id_idx].long_term_key,
            sizeof(long_term_key));
        long_term_key_valid = agent->sent_ids[sent_id_idx].long_term_valid;
        break;
      }
    }
    if (sent_id_idx == STUN_AGENT_MAX_SAVED_IDS) {
      return STUN_VALIDATION_UNMATCHED_RESPONSE;
    }
  }

  ignore_credentials =
      (agent->usage_flags & STUN_AGENT_USAGE_IGNORE_CREDENTIALS) ||
      (stun_message_get_class (msg) == STUN_ERROR &&
       stun_message_find_error (msg, &error_code) ==
          STUN_MESSAGE_RETURN_SUCCESS &&
       (error_code == 400 || error_code == 401)) ||
      (stun_message_get_class (msg) == STUN_INDICATION &&
       (agent->usage_flags & STUN_AGENT_USAGE_NO_INDICATION_AUTH));

  if (key == NULL &&
      ignore_credentials == 0 &&
      (stun_message_get_class (msg) == STUN_REQUEST ||
       stun_message_get_class (msg) == STUN_INDICATION) &&
      (((agent->usage_flags & STUN_AGENT_USAGE_SHORT_TERM_CREDENTIALS) &&
       (!stun_message_has_attribute (msg, STUN_ATTRIBUTE_USERNAME) ||
        !stun_message_has_attribute (msg, STUN_ATTRIBUTE_MESSAGE_INTEGRITY))) ||
      ((agent->usage_flags & STUN_AGENT_USAGE_LONG_TERM_CREDENTIALS) &&
        stun_message_get_class (msg) == STUN_REQUEST &&
        (!stun_message_has_attribute (msg, STUN_ATTRIBUTE_USERNAME) ||
         !stun_message_has_attribute (msg, STUN_ATTRIBUTE_MESSAGE_INTEGRITY) ||
         !stun_message_has_attribute (msg, STUN_ATTRIBUTE_NONCE) ||
         !stun_message_has_attribute (msg, STUN_ATTRIBUTE_REALM))) ||
       ((agent->usage_flags & STUN_AGENT_USAGE_IGNORE_CREDENTIALS) == 0 &&
         stun_message_has_attribute (msg, STUN_ATTRIBUTE_USERNAME) &&
         !stun_message_has_attribute (msg, STUN_ATTRIBUTE_MESSAGE_INTEGRITY)))) {
        return STUN_VALIDATION_UNAUTHORIZED_BAD_REQUEST;
  }

  if (stun_message_has_attribute (msg, STUN_ATTRIBUTE_MESSAGE_INTEGRITY) &&
      ((key == NULL && ignore_credentials == 0) ||
          (agent->usage_flags & STUN_AGENT_USAGE_FORCE_VALIDATER))) {
    username_len = 0;
    username = (uint8_t *) stun_message_find (msg, STUN_ATTRIBUTE_USERNAME,
        &username_len);
    if (validater == NULL ||
        validater (agent, msg, username, username_len,
            &key, &key_len, validater_data) == FALSE) {
      return STUN_VALIDATION_UNAUTHORIZED;
    }
  }

  if (ignore_credentials == 0 && key != NULL && key_len > 0) {
    hash = (uint8_t *) stun_message_find (msg,
        STUN_ATTRIBUTE_MESSAGE_INTEGRITY, &hlen);

    if (hash) {
      /* We must give the size from start to the end of the attribute
         because you might have a FINGERPRINT attribute after it... */
      if (agent->usage_flags & STUN_AGENT_USAGE_LONG_TERM_CREDENTIALS) {
        uint8_t *realm = NULL;
        uint8_t *username = NULL;
        uint16_t realm_len;
        uint16_t username_len;
        uint8_t md5[16];

        if (long_term_key_valid) {
          memcpy (md5, long_term_key, sizeof (md5));
        } else {
          realm = (uint8_t *) stun_message_find (msg,  STUN_ATTRIBUTE_REALM, &realm_len);
          username = (uint8_t *) stun_message_find (msg,
              STUN_ATTRIBUTE_USERNAME, &username_len);
          if (username == NULL || realm == NULL) {
            return STUN_VALIDATION_UNAUTHORIZED;
          }
          stun_hash_creds (realm, realm_len,
              username,  username_len,
              key, key_len, md5);
        }

        memcpy (msg->long_term_key, md5, sizeof(md5));
        msg->long_term_valid = TRUE;

        if (agent->compatibility == STUN_COMPATIBILITY_RFC3489) {
          stun_sha1 (msg->buffer, hash + 20 - msg->buffer, hash - msg->buffer,
              sha, md5, sizeof(md5), TRUE);
        } else if (agent->compatibility == STUN_COMPATIBILITY_WLM2009) {
          stun_sha1 (msg->buffer, hash + 20 - msg->buffer,
              stun_message_length (msg) - 20, sha, md5, sizeof(md5), TRUE);
        } else {
          stun_sha1 (msg->buffer, hash + 20 - msg->buffer,
              hash - msg->buffer, sha, md5, sizeof(md5), FALSE);
        }
      } else {
        if (agent->compatibility == STUN_COMPATIBILITY_RFC3489) {
          stun_sha1 (msg->buffer, hash + 20 - msg->buffer, hash - msg->buffer,
              sha, key, key_len, TRUE);
        } else if (agent->compatibility == STUN_COMPATIBILITY_WLM2009) {
          stun_sha1 (msg->buffer, hash + 20 - msg->buffer,
              stun_message_length (msg) - 20, sha, key, key_len, TRUE);
        } else {
          stun_sha1 (msg->buffer, hash + 20 - msg->buffer,
              hash - msg->buffer, sha, key, key_len, FALSE);
        }
      }

      stun_debug (" Message HMAC-SHA1 fingerprint:");
      stun_debug ("\nkey     : ");
      stun_debug_bytes (key, key_len);
      stun_debug ("\n  expected: ");
      stun_debug_bytes (sha, sizeof (sha));
      stun_debug ("\n  received: ");
      stun_debug_bytes (hash, sizeof (sha));
      stun_debug ("\n");

      if (memcmp (sha, hash, sizeof (sha)))  {
        stun_debug ("STUN auth error: SHA1 fingerprint mismatch!\n");
        return STUN_VALIDATION_UNAUTHORIZED;
      }

      stun_debug ("STUN auth: OK!\n");
      msg->key = key;
      msg->key_len = key_len;
    } else if (!(stun_message_get_class (msg) == STUN_ERROR &&
        stun_message_find_error (msg, &error_code) ==
            STUN_MESSAGE_RETURN_SUCCESS &&
        (error_code == 400 || error_code == 401))) {
      stun_debug ("STUN auth error: No message integrity attribute!\n");
      return STUN_VALIDATION_UNAUTHORIZED;
    }
  }


  if (sent_id_idx != -1 && sent_id_idx < STUN_AGENT_MAX_SAVED_IDS) {
    agent->sent_ids[sent_id_idx].valid = FALSE;
  }

  if (stun_agent_find_unknowns (agent, msg, &unknown, 1) > 0) {
    if (stun_message_get_class (msg) == STUN_REQUEST)
      return STUN_VALIDATION_UNKNOWN_REQUEST_ATTRIBUTE;
    else
      return STUN_VALIDATION_UNKNOWN_ATTRIBUTE;
  }
  return STUN_VALIDATION_SUCCESS;

}
コード例 #4
0
ファイル: turn.c プロジェクト: ChinnaSuhas/ossbuild
StunUsageTurnReturn stun_usage_turn_process (StunMessage *msg,
    struct sockaddr *relay_addr, socklen_t *relay_addrlen,
    struct sockaddr *addr, socklen_t *addrlen,
    struct sockaddr *alternate_server, socklen_t *alternate_server_len,
    uint32_t *bandwidth, uint32_t *lifetime,
    StunUsageTurnCompatibility compatibility)
{
  int val, code = -1;
  StunUsageTurnReturn ret = STUN_USAGE_TURN_RETURN_RELAY_SUCCESS;

  if (stun_message_get_method (msg) != STUN_ALLOCATE)
    return STUN_USAGE_TURN_RETURN_INVALID;

  switch (stun_message_get_class (msg))
  {
    case STUN_REQUEST:
    case STUN_INDICATION:
      return STUN_USAGE_TURN_RETURN_INVALID;

    case STUN_RESPONSE:
      break;

    case STUN_ERROR:
      if (stun_message_find_error (msg, &code) != STUN_MESSAGE_RETURN_SUCCESS) {
        /* missing ERROR-CODE: ignore message */
        return STUN_USAGE_TURN_RETURN_INVALID;
      }

      /* NOTE: currently we ignore unauthenticated messages if the context
       * is authenticated, for security reasons. */
      stun_debug (" STUN error message received (code: %d)\n", code);

      /* ALTERNATE-SERVER mechanism */
      if ((code / 100) == 3) {
        if (alternate_server && alternate_server_len) {
          if (stun_message_find_addr (msg, STUN_ATTRIBUTE_ALTERNATE_SERVER,
                  alternate_server, alternate_server_len) !=
              STUN_MESSAGE_RETURN_SUCCESS) {
            stun_debug (" Unexpectedly missing ALTERNATE-SERVER attribute\n");
            return STUN_USAGE_TURN_RETURN_ERROR;
          }
        } else {
          if (!stun_message_has_attribute (msg,
                  STUN_ATTRIBUTE_ALTERNATE_SERVER)) {
            stun_debug (" Unexpectedly missing ALTERNATE-SERVER attribute\n");
            return STUN_USAGE_TURN_RETURN_ERROR;
          }
        }

        stun_debug ("Found alternate server\n");
        return STUN_USAGE_TURN_RETURN_ALTERNATE_SERVER;

      }
      return STUN_USAGE_TURN_RETURN_ERROR;
  }

  stun_debug ("Received %u-bytes STUN message\n", stun_message_length (msg));

  if (compatibility == STUN_USAGE_TURN_COMPATIBILITY_DRAFT9) {
    val = stun_message_find_xor_addr (msg,
        STUN_ATTRIBUTE_XOR_MAPPED_ADDRESS, addr, addrlen);

    if (val == STUN_MESSAGE_RETURN_SUCCESS)
      ret = STUN_USAGE_TURN_RETURN_MAPPED_SUCCESS;
    val = stun_message_find_xor_addr (msg,
        STUN_ATTRIBUTE_RELAY_ADDRESS, relay_addr, relay_addrlen);
    if (val != STUN_MESSAGE_RETURN_SUCCESS) {
      stun_debug (" No RELAYED-ADDRESS: %d\n", val);
      return STUN_USAGE_TURN_RETURN_ERROR;
    }
  } else if (compatibility == STUN_USAGE_TURN_COMPATIBILITY_GOOGLE) {
    val = stun_message_find_addr (msg,
        STUN_ATTRIBUTE_MAPPED_ADDRESS, relay_addr, relay_addrlen);
    if (val != STUN_MESSAGE_RETURN_SUCCESS) {
      stun_debug (" No MAPPED-ADDRESS: %d\n", val);
      return STUN_USAGE_TURN_RETURN_ERROR;
    }
  } else if (compatibility == STUN_USAGE_TURN_COMPATIBILITY_MSN) {
    val = stun_message_find_addr (msg,
        STUN_ATTRIBUTE_MSN_MAPPED_ADDRESS, addr, addrlen);

    if (val == STUN_MESSAGE_RETURN_SUCCESS)
      ret = STUN_USAGE_TURN_RETURN_MAPPED_SUCCESS;

    val = stun_message_find_addr (msg,
        STUN_ATTRIBUTE_MAPPED_ADDRESS, relay_addr, relay_addrlen);
    if (val != STUN_MESSAGE_RETURN_SUCCESS) {
      stun_debug (" No MAPPED-ADDRESS: %d\n", val);
      return STUN_USAGE_TURN_RETURN_ERROR;
    }
  }

  stun_message_find32 (msg, STUN_ATTRIBUTE_LIFETIME, lifetime);
  stun_message_find32 (msg, STUN_ATTRIBUTE_BANDWIDTH, bandwidth);

  stun_debug (" Mapped address found!\n");
  return ret;

}
コード例 #5
0
ファイル: test_udp_server.c プロジェクト: roxlu/krx_rtc
int handle_stun(udp_conn* c, uint8_t *packet, size_t len) {

  StunAgent agent;
  StunValidationStatus status;
  StunAgentUsageFlags flags;
  StunMessage request;
  StunMessage response;
  int ret;
  size_t output_size;
  uint8_t output[1024];

  flags = STUN_AGENT_USAGE_IGNORE_CREDENTIALS; //  | STUN_AGENT_USAGE_USE_FINGERPRINT;  

  static const uint16_t attr[] = { 
    STUN_ATTRIBUTE_MAPPED_ADDRESS,
    STUN_ATTRIBUTE_RESPONSE_ADDRESS,
    STUN_ATTRIBUTE_CHANGE_REQUEST,
    STUN_ATTRIBUTE_SOURCE_ADDRESS,
    STUN_ATTRIBUTE_CHANGED_ADDRESS,
    STUN_ATTRIBUTE_USERNAME,
    STUN_ATTRIBUTE_PASSWORD,
    STUN_ATTRIBUTE_MESSAGE_INTEGRITY,
    STUN_ATTRIBUTE_ERROR_CODE,
    STUN_ATTRIBUTE_UNKNOWN_ATTRIBUTES,
    STUN_ATTRIBUTE_REFLECTED_FROM,
    STUN_ATTRIBUTE_CHANNEL_NUMBER,
    STUN_ATTRIBUTE_LIFETIME,
    STUN_ATTRIBUTE_MS_ALTERNATE_SERVER,
    STUN_ATTRIBUTE_MAGIC_COOKIE,
    STUN_ATTRIBUTE_BANDWIDTH,
    STUN_ATTRIBUTE_DESTINATION_ADDRESS,
    STUN_ATTRIBUTE_REMOTE_ADDRESS,
    STUN_ATTRIBUTE_PEER_ADDRESS,
    STUN_ATTRIBUTE_XOR_PEER_ADDRESS,
    STUN_ATTRIBUTE_DATA,
    STUN_ATTRIBUTE_REALM,
    STUN_ATTRIBUTE_NONCE,
    STUN_ATTRIBUTE_RELAY_ADDRESS,
    STUN_ATTRIBUTE_RELAYED_ADDRESS,
    STUN_ATTRIBUTE_XOR_RELAYED_ADDRESS,
    STUN_ATTRIBUTE_REQUESTED_ADDRESS_TYPE,
    STUN_ATTRIBUTE_REQUESTED_PORT_PROPS,
    STUN_ATTRIBUTE_REQUESTED_PROPS,
    STUN_ATTRIBUTE_EVEN_PORT,
    STUN_ATTRIBUTE_REQUESTED_TRANSPORT,
    STUN_ATTRIBUTE_DONT_FRAGMENT,
    STUN_ATTRIBUTE_XOR_MAPPED_ADDRESS,
    STUN_ATTRIBUTE_TIMER_VAL,
    STUN_ATTRIBUTE_REQUESTED_IP,
    STUN_ATTRIBUTE_RESERVATION_TOKEN,
    STUN_ATTRIBUTE_CONNECT_STAT,
    STUN_ATTRIBUTE_PRIORITY,
    STUN_ATTRIBUTE_USE_CANDIDATE,
    STUN_ATTRIBUTE_OPTIONS,
    STUN_ATTRIBUTE_MS_VERSION,
    STUN_ATTRIBUTE_SOFTWARE,
    STUN_ATTRIBUTE_ALTERNATE_SERVER,
    STUN_ATTRIBUTE_FINGERPRINT,
    STUN_ATTRIBUTE_ICE_CONTROLLED,
    STUN_ATTRIBUTE_ICE_CONTROLLING,
    STUN_ATTRIBUTE_MS_SEQUENCE_NUMBER,
    STUN_ATTRIBUTE_CANDIDATE_IDENTIFIER
  };

  /* initialize our agent to be compatible with RFC5389 (= with TLS support) */
  output_size = 0;
  memset(output, 0, sizeof(output));
  stun_agent_init(&agent, attr, STUN_COMPATIBILITY_RFC5389, flags);

  /* validate the request */
  status = stun_agent_validate(&agent, &request, packet, len, NULL, NULL);
  print_stun_validation_status(status);

  /* check the class */
  StunClass request_class = stun_message_get_class(&request);
  print_stun_class(request_class);
  if(request_class == STUN_ERROR) {
    printf("Error: request stun class failed.\n");
    exit(0);
  }

  /* what stun method? */
  StunMethod request_method = stun_message_get_method(&request);
  print_stun_method(request_method);

  /* initialize the response */
  ret = stun_agent_init_response(&agent, &response, output, 1024, &request);
  printf("Stun agent_init_response ret: %d\n", ret);

  /* add xor-mapped-address */
  uint32_t magic_cookie = 0;
  uint8_t* cookie_ptr = NULL;
  StunTransactionId transid;
  socklen_t sock_len = 0;
  char client_ip[16] = { 0 } ;
  StunMessageReturn stun_ret = STUN_MESSAGE_RETURN_INVALID;

  stun_message_id(&response, transid);
  magic_cookie = *((uint32_t*)transid);
  sock_len = sizeof(c->client);
  cookie_ptr = (uint8_t*) &magic_cookie;
  inet_ntop(AF_INET, &c->client.sin_addr.s_addr, client_ip, sizeof(client_ip));

  stun_ret = stun_message_append_xor_addr(&response, STUN_ATTRIBUTE_XOR_MAPPED_ADDRESS, (const struct sockaddr*)&c->client, sock_len);
  print_stun_message_return(stun_ret);

  printf("Received data from: %s\n", client_ip);
  printf("Magic cookie: %02X %02X %02X %02X\n", cookie_ptr[0], cookie_ptr[1], cookie_ptr[2], cookie_ptr[3]);
  
  // username
  // --------
  const char* username = NULL;
  uint16_t username_len = 0;
  username = (const char*)stun_message_find(&request, STUN_ATTRIBUTE_USERNAME, &username_len);
  printf("Username: %s, len: %d\n", username, (int)username_len);

#if 0
  if(username) {
    StunMessageReturn username_res = stun_message_append_bytes(&response, STUN_ATTRIBUTE_USERNAME, username, username_len);
    print_stun_message_return(username_res);

  }
  uint32_t fingerprint = 0;
  if(stun_message_find32(&request, STUN_ATTRIBUTE_FINGERPRINT, &fingerprint) == STUN_MESSAGE_RETURN_SUCCESS) {
    printf("Got fingerprint: %d\n", fingerprint);
    if(stun_message_append32(&response, STUN_ATTRIBUTE_FINGERPRINT, fingerprint) != STUN_MESSAGE_RETURN_SUCCESS) {
      printf("Error while adding the fingerprint.\n");
    }
  }
#endif

  // password
  const char* password = ucon_ptr->stun_pw; // "94ccca06d14fb48c135bdaff30560c4d";
  uint16_t password_len = strlen(password) + 1;
  output_size = stun_agent_finish_message(&agent, &response, (const uint8_t*) password, password_len);

  // answer to the connection
  krx_udp_send(c, output, output_size);

  print_buffer(output, output_size);
  return 0;
}
コード例 #6
0
ファイル: test-parse.c プロジェクト: WilliamRen/libnice
/* Tests for message attribute parsing */
static void test_attribute (void)
{
  static const uint8_t acme[] =
      {0x04, 0x55, 0x00, 0x6C, // <-- update message length if needed!!
       0x21, 0x12, 0xA4, 0x42, // cookie
       0x76, 0x54, 0x32, 0x10,
       0xfe, 0xdc, 0xba, 0x98,
       0x76, 0x54, 0x32, 0x10,

       /* FF01: empty */
       0xff, 0x01, 0x00, 0x00,

       /* FF02: address of unknown family, 32-bits */
       0xff, 0x02, 0x00, 0x04,
       0x41, 0x42, 0x43, 0x44,

       /* FF03: too short IPv6 address */
       0xff, 0x03, 0x00, 0x06,
       0x00, 0x02, 0x12, 0x34,
       0x20, 0x01, 0x0d, 0xb8,

       /* FF04: valid IPv4 address, 64-bits */
       0xff, 0x04, 0x00, 0x08,
       0x00, 0x01, 0x12, 0x34,
       0xc0, 0x00, 0x02, 0x01,

       /* FF05: too long IPv4 address */
       0xff, 0x05, 0x00, 0x0A,
       0x00, 0x01, 0x12, 0x34,
       0xc0, 0x00, 0x02, 0x01,
       0x66, 0x60, 0x00, 0x00,

       /* FF06: valid xor'd IPv6 address, 160-bits */
       0xff, 0x06, 0x00, 0x14,
       0x00, 0x02, 0x12, 0x34,
       0x01, 0x13, 0xa9, 0xfa,
       0xa8, 0xf9, 0x8c, 0xff,
       0x20, 0x26, 0x74, 0x48,
       0x8c, 0x9a, 0xec, 0xfd,

       /* dummy USERNAME header */
       0x00, 0x06, 0x00, 0x04,
       0x41, 0x42, 0x43, 0x44,

       /* MESSAGE-INTEGRITY attribute */
       0x00, 0x08, 0x00, 0x14,
       0x0b, 0xc4, 0xb2, 0x0c,
       0x94, 0x58, 0xbb, 0x25,
       0xa3, 0x22, 0x1a, 0xc8,
       0xe1, 0x87, 0x32, 0x36,
       0x3a, 0xfc, 0xe2, 0xc3};

  union
  {
    struct sockaddr sa;
    struct sockaddr_in6 s6;
  } addr;
  socklen_t addrlen;
  uint32_t dword;
  uint64_t qword;
  char str[STUN_MAX_STR];

  StunAgent agent;
  StunMessage msg;
  uint16_t known_attributes[] = {STUN_ATTRIBUTE_MESSAGE_INTEGRITY, STUN_ATTRIBUTE_USERNAME, 0};

  printf ("Attribute test message length: %lu\n", sizeof (acme));

  stun_agent_init (&agent, known_attributes,
      STUN_COMPATIBILITY_RFC5389, STUN_AGENT_USAGE_SHORT_TERM_CREDENTIALS);

  if (stun_agent_validate (&agent, &msg, acme, sizeof(acme),
          NULL, NULL) != STUN_VALIDATION_UNAUTHORIZED)
    fatal ("Unauthorized validation failed");

  if (stun_agent_validate (&agent, &msg, acme, sizeof(acme),
          test_attribute_validater, "bad__guy") != STUN_VALIDATION_UNAUTHORIZED)
    fatal ("invalid password validation failed");

  if (stun_agent_validate (&agent, &msg, acme, sizeof(acme),
          test_attribute_validater, "good_guy") != STUN_VALIDATION_SUCCESS)
    fatal ("good password validation failed");

  if (stun_message_has_attribute (&msg, 0xff00))
    fatal ("Absent attribute test failed");
  if (!stun_message_has_attribute (&msg, 0xff01))
    fatal ("Present attribute test failed");

  if (stun_message_find_flag (&msg, 0xff00) != STUN_MESSAGE_RETURN_NOT_FOUND)
    fatal ("Absent flag test failed");
  if (stun_message_find_flag (&msg, 0xff01) != STUN_MESSAGE_RETURN_SUCCESS)
    fatal ("Flag test failed");
  if (stun_message_find_flag (&msg, 0xff02) != STUN_MESSAGE_RETURN_INVALID)
    fatal ("Too big flag test failed");

  if (stun_message_find32 (&msg, 0xff00, &dword) !=
      STUN_MESSAGE_RETURN_NOT_FOUND)
    fatal ("Absent dword test failed");
  if (stun_message_find32 (&msg, 0xff01, &dword) != STUN_MESSAGE_RETURN_INVALID)
    fatal ("Bad dword test failed");
  if (stun_message_find32 (&msg, 0xff02, &dword) != STUN_MESSAGE_RETURN_SUCCESS)
    fatal ("Double-word test failed");

  if (stun_message_find64 (&msg, 0xff00, &qword) !=
      STUN_MESSAGE_RETURN_NOT_FOUND)
    fatal ("Absent qword test failed");
  if (stun_message_find64 (&msg, 0xff01, &qword) != STUN_MESSAGE_RETURN_INVALID)
    fatal ("Bad qword test failed");
  if (stun_message_find64 (&msg, 0xff04, &qword) != STUN_MESSAGE_RETURN_SUCCESS)
    fatal ("Quad-word test failed");

  if (stun_message_find_string (&msg, 0xff00, str, STUN_MAX_CP) !=
      STUN_MESSAGE_RETURN_NOT_FOUND)
    fatal ("Absent string test failed");
  if ((stun_message_find_string (&msg, 0xff02, str, STUN_MAX_CP) !=
          STUN_MESSAGE_RETURN_SUCCESS)
   || strcmp (str, "ABCD"))
    fatal ("String test failed");

  addrlen = sizeof (addr);
  if (stun_message_find_addr (&msg, 0xff01, &addr.sa, &addrlen) !=
      STUN_MESSAGE_RETURN_INVALID)
    fatal ("Too short addres test failed");
  addrlen = sizeof (addr);
  if (stun_message_find_addr (&msg, 0xff02, &addr.sa, &addrlen) !=
      STUN_MESSAGE_RETURN_UNSUPPORTED_ADDRESS)
    fatal ("Unknown address family test failed");
  addrlen = sizeof (addr);
  if (stun_message_find_addr (&msg, 0xff03, &addr.sa, &addrlen) !=
      STUN_MESSAGE_RETURN_INVALID)
    fatal ("Too short IPv6 address test failed");
  addrlen = sizeof (addr);
  if (stun_message_find_addr (&msg, 0xff04, &addr.sa, &addrlen) !=
      STUN_MESSAGE_RETURN_SUCCESS)
    fatal ("IPv4 address test failed");
  addrlen = sizeof (addr);
  if (stun_message_find_addr (&msg, 0xff05, &addr.sa, &addrlen) !=
      STUN_MESSAGE_RETURN_INVALID)
    fatal ("Too big IPv4 address test failed");
  addrlen = sizeof (addr);
  if (stun_message_find_xor_addr (&msg, 0xff06, &addr.sa, &addrlen) !=
      STUN_MESSAGE_RETURN_SUCCESS ||
      memcmp (&addr.s6.sin6_addr, "\x20\x01\x0d\xb8""\xde\xad\xbe\xef"
                                  "\xde\xfa\xce\xd0""\xfa\xce\xde\xed", 16))
    fatal ("IPv6 address test failed");

}