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/*
* Copyright 2013 University of Chicago
* Contact: Bryce Allen
* Copyright 2013 Collabora Ltd.
* Contact: Youness Alaoui
*
* The contents of this file are subject to the Mozilla Public License Version
* 1.1 (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
* http://www.mozilla.org/MPL/
*
* Software distributed under the License is distributed on an "AS IS" basis,
* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
* for the specific language governing rights and limitations under the
* License.
*
* Alternatively, the contents of this file may be used under the terms of the
* the GNU Lesser General Public License Version 2.1 (the "LGPL"), in which
* case the provisions of LGPL are applicable instead of those above. If you
* wish to allow use of your version of this file only under the terms of the
* LGPL and not to allow others to use your version of this file under the
* MPL, indicate your decision by deleting the provisions above and replace
* them with the notice and other provisions required by the LGPL. If you do
* not delete the provisions above, a recipient may use your version of this
* file under either the MPL or the LGPL.
*/
/*
* Example using libnice to negotiate a UDP connection between two clients,
* possibly on the same network or behind different NATs and/or stateful
* firewalls.
*
* Build:
* gcc -o simple-example simple-example.c `pkg-config --cflags --libs nice`
*
* Run two clients, one controlling and one controlled:
* simple-example 0 $(host -4 -t A stun.stunprotocol.org | awk '{ print $4 }')
* simple-example 1 $(host -4 -t A stun.stunprotocol.org | awk '{ print $4 }')
*/
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <ctype.h>
#include <agent.h>
static GMainLoop *gloop;
static GIOChannel* io_stdin;
static guint stream_id;
static const gchar *candidate_type_name[] = {"host", "srflx", "prflx", "relay"};
static const gchar *state_name[] = {"disconnected", "gathering", "connecting",
"connected", "ready", "failed"};
static int print_local_data(NiceAgent *agent, guint stream_id,
guint component_id);
static int parse_remote_data(NiceAgent *agent, guint stream_id,
guint component_id, char *line);
static void cb_candidate_gathering_done(NiceAgent *agent, guint stream_id,
gpointer data);
static void cb_new_selected_pair(NiceAgent *agent, guint stream_id,
guint component_id, gchar *lfoundation,
gchar *rfoundation, gpointer data);
static void cb_component_state_changed(NiceAgent *agent, guint stream_id,
guint component_id, guint state,
gpointer data);
static void cb_nice_recv(NiceAgent *agent, guint stream_id, guint component_id,
guint len, gchar *buf, gpointer data);
static gboolean stdin_remote_info_cb (GIOChannel *source, GIOCondition cond,
gpointer data);
static gboolean stdin_send_data_cb (GIOChannel *source, GIOCondition cond,
gpointer data);
int
main(int argc, char *argv[])
{
NiceAgent *agent;
gchar *stun_addr = NULL;
guint stun_port;
gboolean controlling;
// Parse arguments
if (argc > 4 || argc < 2 || argv[1][1] != '\0') {
fprintf(stderr, "Usage: %s 0|1 stun_addr [stun_port]\n", argv[0]);
return EXIT_FAILURE;
}
controlling = argv[1][0] - '0';
if (controlling != 0 && controlling != 1) {
fprintf(stderr, "Usage: %s 0|1 stun_addr [stun_port]\n", argv[0]);
return EXIT_FAILURE;
}
if (argc > 2) {
stun_addr = argv[2];
if (argc > 3)
stun_port = atoi(argv[3]);
else
stun_port = 3478;
g_debug("Using stun server '[%s]:%u'\n", stun_addr, stun_port);
}
g_type_init();
gloop = g_main_loop_new(NULL, FALSE);
io_stdin = g_io_channel_unix_new(fileno(stdin));
// Create the nice agent
agent = nice_agent_new(g_main_loop_get_context (gloop),
NICE_COMPATIBILITY_RFC5245);
if (agent == NULL)
g_error("Failed to create agent");
// Set the STUN settings and controlling mode
if (stun_addr) {
g_object_set(G_OBJECT(agent), "stun-server", stun_addr, NULL);
g_object_set(G_OBJECT(agent), "stun-server-port", stun_port, NULL);
}
g_object_set(G_OBJECT(agent), "controlling-mode", controlling, NULL);
// Connect to the signals
g_signal_connect(G_OBJECT(agent), "candidate-gathering-done",
G_CALLBACK(cb_candidate_gathering_done), NULL);
g_signal_connect(G_OBJECT(agent), "new-selected-pair",
G_CALLBACK(cb_new_selected_pair), NULL);
g_signal_connect(G_OBJECT(agent), "component-state-changed",
G_CALLBACK(cb_component_state_changed), NULL);
// Create a new stream with one component
stream_id = nice_agent_add_stream(agent, 1);
if (stream_id == 0)
g_error("Failed to add stream");
// Attach to the component to receive the data
// Without this call, candidates cannot be gathered
nice_agent_attach_recv(agent, stream_id, 1,
g_main_loop_get_context (gloop), cb_nice_recv, NULL);
// Start gathering local candidates
if (!nice_agent_gather_candidates(agent, stream_id))
g_error("Failed to start candidate gathering");
g_debug("waiting for candidate-gathering-done signal...");
// Run the mainloop. Everything else will happen asynchronously
// when the candidates are done gathering.
g_main_loop_run (gloop);
g_main_loop_unref(gloop);
g_object_unref(agent);
g_io_channel_unref (io_stdin);
return EXIT_SUCCESS;
}
static void
cb_candidate_gathering_done(NiceAgent *agent, guint stream_id,
gpointer data)
{
g_debug("SIGNAL candidate gathering done\n");
// Candidate gathering is done. Send our local candidates on stdout
printf("Copy this line to remote client:\n");
printf("\n ");
print_local_data(agent, stream_id, 1);
printf("\n");
// Listen on stdin for the remote candidate list
printf("Enter remote data (single line, no wrapping):\n");
g_io_add_watch(io_stdin, G_IO_IN, stdin_remote_info_cb, agent);
printf("> ");
fflush (stdout);
}
static gboolean
stdin_remote_info_cb (GIOChannel *source, GIOCondition cond,
gpointer data)
{
NiceAgent *agent = data;
gchar *line = NULL;
int rval;
gboolean ret = TRUE;
if (g_io_channel_read_line (source, &line, NULL, NULL, NULL) ==
G_IO_STATUS_NORMAL) {
// Parse remote candidate list and set it on the agent
rval = parse_remote_data(agent, stream_id, 1, line);
if (rval == EXIT_SUCCESS) {
// Return FALSE so we stop listening to stdin since we parsed the
// candidates correctly
ret = FALSE;
g_debug("waiting for state READY or FAILED signal...");
} else {
fprintf(stderr, "ERROR: failed to parse remote data\n");
printf("Enter remote data (single line, no wrapping):\n");
printf("> ");
fflush (stdout);
}
g_free (line);
}
return ret;
}
static void
cb_component_state_changed(NiceAgent *agent, guint stream_id,
guint component_id, guint state,
gpointer data)
{
g_debug("SIGNAL: state changed %d %d %s[%d]\n",
stream_id, component_id, state_name[state], state);
if (state == NICE_COMPONENT_STATE_READY) {
NiceCandidate *local, *remote;
// Get current selected candidate pair and print IP address used
if (nice_agent_get_selected_pair (agent, stream_id, component_id,
&local, &remote)) {
gchar ipaddr[INET6_ADDRSTRLEN];
nice_address_to_string(&local->addr, ipaddr);
printf("\nNegotiation complete: ([%s]:%d,",
ipaddr, nice_address_get_port(&local->addr));
nice_address_to_string(&remote->addr, ipaddr);
printf(" [%s]:%d)\n", ipaddr, nice_address_get_port(&remote->addr));
}
// Listen to stdin and send data written to it
printf("\nSend lines to remote (Ctrl-D to quit):\n");
g_io_add_watch(io_stdin, G_IO_IN, stdin_send_data_cb, agent);
printf("> ");
fflush (stdout);
} else if (state == NICE_COMPONENT_STATE_FAILED) {
g_main_loop_quit (gloop);
}
}
static gboolean
stdin_send_data_cb (GIOChannel *source, GIOCondition cond,
gpointer data)
{
NiceAgent *agent = data;
gchar *line = NULL;
if (g_io_channel_read_line (source, &line, NULL, NULL, NULL) ==
G_IO_STATUS_NORMAL) {
nice_agent_send(agent, stream_id, 1, strlen(line), line);
g_free (line);
printf("> ");
fflush (stdout);
}
return TRUE;
}
static void
cb_new_selected_pair(NiceAgent *agent, guint stream_id,
guint component_id, gchar *lfoundation,
gchar *rfoundation, gpointer data)
{
g_debug("SIGNAL: selected pair %s %s", lfoundation, rfoundation);
}
static void
cb_nice_recv(NiceAgent *agent, guint stream_id, guint component_id,
guint len, gchar *buf, gpointer data)
{
printf("%.*s", len, buf);
fflush(stdout);
}
static NiceCandidate *
parse_candidate(char *scand, guint stream_id)
{
NiceCandidate *cand = NULL;
NiceCandidateType ntype;
gchar **tokens = NULL;
guint i;
tokens = g_strsplit (scand, ",", 5);
for (i = 0; tokens && tokens[i]; i++);
if (i != 5)
goto end;
for (i = 0; i < G_N_ELEMENTS (candidate_type_name); i++) {
if (strcmp(tokens[4], candidate_type_name[i]) == 0) {
ntype = i;
break;
}
}
if (i == G_N_ELEMENTS (candidate_type_name))
goto end;
cand = nice_candidate_new(ntype);
cand->component_id = 1;
cand->stream_id = stream_id;
cand->transport = NICE_CANDIDATE_TRANSPORT_UDP;
strncpy(cand->foundation, tokens[0], NICE_CANDIDATE_MAX_FOUNDATION);
cand->priority = atoi (tokens[1]);
if (!nice_address_set_from_string(&cand->addr, tokens[2])) {
g_message("failed to parse addr: %s", tokens[2]);
nice_candidate_free(cand);
cand = NULL;
goto end;
}
nice_address_set_port(&cand->addr, atoi (tokens[3]));
end:
g_strfreev(tokens);
return cand;
}
static int
print_local_data (NiceAgent *agent, guint stream_id, guint component_id)
{
int result = EXIT_FAILURE;
gchar *local_ufrag = NULL;
gchar *local_password = NULL;
gchar ipaddr[INET6_ADDRSTRLEN];
GSList *cands = NULL, *item;
if (!nice_agent_get_local_credentials(agent, stream_id,
&local_ufrag, &local_password))
goto end;
cands = nice_agent_get_local_candidates(agent, stream_id, component_id);
if (cands == NULL)
goto end;
printf("%s %s", local_ufrag, local_password);
for (item = cands; item; item = item->next) {
NiceCandidate *c = (NiceCandidate *)item->data;
nice_address_to_string(&c->addr, ipaddr);
// (foundation),(prio),(addr),(port),(type)
printf(" %s,%u,%s,%u,%s",
c->foundation,
c->priority,
ipaddr,
nice_address_get_port(&c->addr),
candidate_type_name[c->type]);
}
printf("\n");
result = EXIT_SUCCESS;
end:
if (local_ufrag)
g_free(local_ufrag);
if (local_password)
g_free(local_password);
if (cands)
g_slist_free_full(cands, (GDestroyNotify)&nice_candidate_free);
return result;
}
static int
parse_remote_data(NiceAgent *agent, guint stream_id,
guint component_id, char *line)
{
GSList *remote_candidates = NULL;
gchar **line_argv = NULL;
const gchar *ufrag = NULL;
const gchar *passwd = NULL;
int result = EXIT_FAILURE;
int i;
line_argv = g_strsplit_set (line, " \t\n", 0);
for (i = 0; line_argv && line_argv[i]; i++) {
if (strlen (line_argv[i]) == 0)
continue;
// first two args are remote ufrag and password
if (!ufrag) {
ufrag = line_argv[i];
} else if (!passwd) {
passwd = line_argv[i];
} else {
// Remaining args are serialized canidates (at least one is required)
NiceCandidate *c = parse_candidate(line_argv[i], stream_id);
if (c == NULL) {
g_message("failed to parse candidate: %s", line_argv[i]);
goto end;
}
remote_candidates = g_slist_prepend(remote_candidates, c);
}
}
if (ufrag == NULL || passwd == NULL || remote_candidates == NULL) {
g_message("line must have at least ufrag, password, and one candidate");
goto end;
}
if (!nice_agent_set_remote_credentials(agent, stream_id, ufrag, passwd)) {
g_message("failed to set remote credentials");
goto end;
}
// Note: this will trigger the start of negotiation.
if (nice_agent_set_remote_candidates(agent, stream_id, component_id,
remote_candidates) < 1) {
g_message("failed to set remote candidates");
goto end;
}
result = EXIT_SUCCESS;
end:
if (line_argv != NULL)
g_strfreev(line_argv);
if (remote_candidates != NULL)
g_slist_free_full(remote_candidates, (GDestroyNotify)&nice_candidate_free);
return result;
}
|