1 #include <catta/core.h>
2 #include <catta/lookup.h>
3 #include <catta/publish.h>
5 #include <catta/simple-watch.h>
6 #include <catta/malloc.h>
7 #include <catta/alternative.h>
8 #include <catta/error.h>
10 #include "meshlink_internal.h"
11 #include "discovery.h"
17 #include <netinet/in.h>
19 #define MESHLINK_MDNS_SERVICE_TYPE "_%s._tcp"
20 #define MESHLINK_MDNS_NAME_KEY "name"
21 #define MESHLINK_MDNS_FINGERPRINT_KEY "fingerprint"
23 static void generate_rand_string(char *buffer, size_t size) {
24 for(size_t i = 0; i < (size - 1); ++i) {
25 buffer[i] = 'a' + (rand() % ('z' - 'a' + 1));
28 buffer[size - 1] = '\0';
31 static void discovery_entry_group_callback(CattaServer *server, CattaSEntryGroup *group, CattaEntryGroupState state, void *userdata) {
34 meshlink_handle_t *mesh = userdata;
38 assert(mesh->catta_server != NULL);
39 assert(mesh->catta_poll != NULL);
41 pthread_mutex_lock(&(mesh->mesh_mutex));
43 /* Called whenever the entry group state changes */
45 case CATTA_ENTRY_GROUP_ESTABLISHED:
46 /* The entry group has been established successfully */
47 logger(mesh, MESHLINK_DEBUG, "Catta Service successfully established.\n");
50 case CATTA_ENTRY_GROUP_COLLISION:
51 logger(mesh, MESHLINK_WARNING, "Catta Service collision.\n");
52 // @TODO can we just set a new name and retry?
55 case CATTA_ENTRY_GROUP_FAILURE :
56 /* Some kind of failure happened while we were registering our services */
57 logger(mesh, MESHLINK_ERROR, "Catta Entry group failure: %s\n", catta_strerror(catta_server_errno(mesh->catta_server)));
58 catta_simple_poll_quit(mesh->catta_poll);
61 case CATTA_ENTRY_GROUP_UNCOMMITED:
62 case CATTA_ENTRY_GROUP_REGISTERING:
66 pthread_mutex_unlock(&(mesh->mesh_mutex));
70 static void discovery_create_services(meshlink_handle_t *mesh) {
71 char *txt_name = NULL;
75 assert(mesh->name != NULL);
76 assert(mesh->myport != NULL);
77 assert(mesh->catta_server != NULL);
78 assert(mesh->catta_poll != NULL);
79 assert(mesh->catta_servicetype != NULL);
80 assert(mesh->self != NULL);
82 pthread_mutex_lock(&(mesh->mesh_mutex));
84 logger(mesh, MESHLINK_DEBUG, "Adding service\n");
86 /* Ifthis is the first time we're called, let's create a new entry group */
87 if(!mesh->catta_group) {
88 if(!(mesh->catta_group = catta_s_entry_group_new(mesh->catta_server, discovery_entry_group_callback, mesh))) {
89 logger(mesh, MESHLINK_ERROR, "catta_entry_group_new() failed: %s\n", catta_strerror(catta_server_errno(mesh->catta_server)));
94 /* Create txt records */
95 size_t txt_name_len = sizeof(MESHLINK_MDNS_NAME_KEY) + 1 + strlen(mesh->name) + 1;
96 txt_name = malloc(txt_name_len);
98 if(txt_name == NULL) {
99 logger(mesh, MESHLINK_ERROR, "Could not allocate memory for TXT record\n");
103 snprintf(txt_name, txt_name_len, "%s=%s", MESHLINK_MDNS_NAME_KEY, mesh->name);
105 char txt_fingerprint[sizeof(MESHLINK_MDNS_FINGERPRINT_KEY) + 1 + MESHLINK_FINGERPRINTLEN + 1];
106 snprintf(txt_fingerprint, sizeof(txt_fingerprint), "%s=%s", MESHLINK_MDNS_FINGERPRINT_KEY, meshlink_get_fingerprint(mesh, (meshlink_node_t *)mesh->self));
108 /* Add the service */
111 if((ret = catta_server_add_service(mesh->catta_server, mesh->catta_group, CATTA_IF_UNSPEC, CATTA_PROTO_UNSPEC, 0, meshlink_get_fingerprint(mesh, (meshlink_node_t *)mesh->self), mesh->catta_servicetype, NULL, NULL, atoi(mesh->myport), txt_name, txt_fingerprint, NULL)) < 0) {
112 logger(mesh, MESHLINK_ERROR, "Failed to add service: %s\n", catta_strerror(ret));
116 /* Tell the server to register the service */
117 if((ret = catta_s_entry_group_commit(mesh->catta_group)) < 0) {
118 logger(mesh, MESHLINK_ERROR, "Failed to commit entry_group: %s\n", catta_strerror(ret));
125 catta_simple_poll_quit(mesh->catta_poll);
133 pthread_mutex_unlock(&(mesh->mesh_mutex));
136 static void discovery_server_callback(CattaServer *server, CattaServerState state, void *userdata) {
138 meshlink_handle_t *mesh = userdata;
141 assert(mesh != NULL);
144 case CATTA_SERVER_RUNNING:
146 /* The serve has startup successfully and registered its host
147 * name on the network, so it's time to create our services */
148 if(!mesh->catta_group) {
149 discovery_create_services(mesh);
154 case CATTA_SERVER_COLLISION: {
156 assert(mesh->catta_server != NULL);
157 assert(mesh->catta_poll != NULL);
159 /* A host name collision happened. Let's pick a new name for the server */
161 generate_rand_string(hostname, sizeof(hostname));
162 int result = catta_server_set_host_name(mesh->catta_server, hostname);
165 catta_simple_poll_quit(mesh->catta_poll);
170 case CATTA_SERVER_REGISTERING:
172 /* Let's drop our registered services. When the server is back
173 * in CATTA_SERVER_RUNNING state we will register them
174 * again with the new host name. */
175 if(mesh->catta_group) {
176 catta_s_entry_group_reset(mesh->catta_group);
177 mesh->catta_group = NULL;
182 case CATTA_SERVER_FAILURE:
184 assert(mesh->catta_server != NULL);
185 assert(mesh->catta_poll != NULL);
187 /* Terminate on failure */
188 catta_simple_poll_quit(mesh->catta_poll);
191 case CATTA_SERVER_INVALID:
196 static void discovery_resolve_callback(CattaSServiceResolver *resolver, CattaIfIndex interface_, CattaProtocol protocol, CattaResolverEvent event, const char *name, const char *type, const char *domain, const char *host_name, const CattaAddress *address, uint16_t port, CattaStringList *txt, CattaLookupResultFlags flags, void *userdata) {
200 meshlink_handle_t *mesh = userdata;
203 assert(resolver != NULL);
204 assert(mesh != NULL);
205 assert(mesh->catta_server != NULL);
207 /* Called whenever a service has been resolved successfully or timed out */
209 case CATTA_RESOLVER_FAILURE:
211 assert(name != NULL);
212 assert(type != NULL);
213 assert(domain != NULL);
216 case CATTA_RESOLVER_FOUND: {
218 assert(name != NULL);
219 assert(type != NULL);
220 assert(domain != NULL);
221 assert(host_name != NULL);
222 assert(address != NULL);
225 // retrieve fingerprint
226 CattaStringList *node_name_li = catta_string_list_find(txt, MESHLINK_MDNS_NAME_KEY);
227 CattaStringList *node_fp_li = catta_string_list_find(txt, MESHLINK_MDNS_FINGERPRINT_KEY);
229 if(node_name_li != NULL && node_fp_li != NULL) {
230 char *node_name = (char *)catta_string_list_get_text(node_name_li) + strlen(MESHLINK_MDNS_NAME_KEY);
231 char *node_fp = (char *)catta_string_list_get_text(node_fp_li) + strlen(MESHLINK_MDNS_FINGERPRINT_KEY);
233 if(node_name[0] == '=' && node_fp[0] == '=') {
234 pthread_mutex_lock(&(mesh->mesh_mutex));
239 meshlink_node_t *node = meshlink_get_node(mesh, node_name);
242 logger(mesh, MESHLINK_INFO, "Node %s is part of the mesh network.\n", node->name);
245 memset(&naddress, 0, sizeof(naddress));
247 switch(address->proto) {
248 case CATTA_PROTO_INET: {
249 naddress.in.sin_family = AF_INET;
250 naddress.in.sin_port = htons(port);
251 naddress.in.sin_addr.s_addr = address->data.ipv4.address;
255 case CATTA_PROTO_INET6: {
256 naddress.in6.sin6_family = AF_INET6;
257 naddress.in6.sin6_port = htons(port);
258 memcpy(naddress.in6.sin6_addr.s6_addr, address->data.ipv6.address, sizeof(naddress.in6.sin6_addr.s6_addr));
263 naddress.unknown.family = AF_UNKNOWN;
267 if(naddress.unknown.family != AF_UNKNOWN) {
268 meshlink_hint_address(mesh, (meshlink_node_t *)node, (struct sockaddr *)&naddress);
270 logger(mesh, MESHLINK_WARNING, "Could not resolve node %s to a known address family type.\n", node->name);
273 logger(mesh, MESHLINK_WARNING, "Node %s is not part of the mesh network.\n", node_name);
276 pthread_mutex_unlock(&(mesh->mesh_mutex));
283 catta_s_service_resolver_free(resolver);
286 static void discovery_browse_callback(CattaSServiceBrowser *browser, CattaIfIndex interface_, CattaProtocol protocol, CattaBrowserEvent event, const char *name, const char *type, const char *domain, CattaLookupResultFlags flags, void *userdata) {
289 meshlink_handle_t *mesh = userdata;
292 assert(mesh != NULL);
293 assert(mesh->catta_server != NULL);
294 assert(mesh->catta_poll != NULL);
296 /* Called whenever a new services becomes available on the LAN or is removed from the LAN */
298 case CATTA_BROWSER_FAILURE:
299 catta_simple_poll_quit(mesh->catta_poll);
302 case CATTA_BROWSER_NEW:
303 catta_s_service_resolver_new(mesh->catta_server, interface_, protocol, name, type, domain, CATTA_PROTO_UNSPEC, 0, discovery_resolve_callback, mesh);
306 case CATTA_BROWSER_REMOVE:
307 case CATTA_BROWSER_ALL_FOR_NOW:
308 case CATTA_BROWSER_CACHE_EXHAUSTED:
313 static void *discovery_loop(void *userdata) {
314 meshlink_handle_t *mesh = userdata;
317 assert(mesh != NULL);
318 assert(mesh->catta_poll != NULL);
320 catta_simple_poll_loop(mesh->catta_poll);
325 static void discovery_log_cb(CattaLogLevel level, const char *txt) {
326 meshlink_log_level_t mlevel = MESHLINK_CRITICAL;
329 case CATTA_LOG_ERROR:
330 mlevel = MESHLINK_ERROR;
334 mlevel = MESHLINK_WARNING;
337 case CATTA_LOG_NOTICE:
339 mlevel = MESHLINK_INFO;
342 case CATTA_LOG_DEBUG:
344 mlevel = MESHLINK_DEBUG;
348 logger(NULL, mlevel, "%s\n", txt);
351 bool discovery_start(meshlink_handle_t *mesh) {
352 logger(mesh, MESHLINK_DEBUG, "discovery_start called\n");
355 assert(mesh != NULL);
356 assert(mesh->catta_poll == NULL);
357 assert(mesh->catta_server == NULL);
358 assert(mesh->catta_browser == NULL);
359 assert(mesh->discovery_threadstarted == false);
360 assert(mesh->catta_servicetype == NULL);
363 catta_set_log_function(discovery_log_cb);
365 // create service type string
366 size_t servicetype_strlen = sizeof(MESHLINK_MDNS_SERVICE_TYPE) + strlen(mesh->appname) + 1;
367 mesh->catta_servicetype = malloc(servicetype_strlen);
369 if(mesh->catta_servicetype == NULL) {
370 logger(mesh, MESHLINK_ERROR, "Failed to allocate memory for service type string.\n");
374 snprintf(mesh->catta_servicetype, servicetype_strlen, MESHLINK_MDNS_SERVICE_TYPE, mesh->appname);
376 // Allocate discovery loop object
377 if(!(mesh->catta_poll = catta_simple_poll_new())) {
378 logger(mesh, MESHLINK_ERROR, "Failed to create discovery poll object.\n");
382 // generate some unique host name (we actually do not care about it)
384 generate_rand_string(hostname, sizeof(hostname));
386 // Let's set the host name for this server.
387 CattaServerConfig config;
388 catta_server_config_init(&config);
389 config.host_name = catta_strdup(hostname);
390 config.publish_workstation = 0;
391 config.disallow_other_stacks = 0;
392 config.publish_hinfo = 0;
393 config.publish_addresses = 1;
394 config.publish_no_reverse = 1;
396 /* Allocate a new server */
398 mesh->catta_server = catta_server_new(catta_simple_poll_get(mesh->catta_poll), &config, discovery_server_callback, mesh, &error);
400 /* Free the configuration data */
401 catta_server_config_free(&config);
403 /* Check wether creating the server object succeeded */
404 if(!mesh->catta_server) {
405 logger(mesh, MESHLINK_ERROR, "Failed to create discovery server: %s\n", catta_strerror(error));
409 // Create the service browser
410 if(!(mesh->catta_browser = catta_s_service_browser_new(mesh->catta_server, CATTA_IF_UNSPEC, CATTA_PROTO_UNSPEC, mesh->catta_servicetype, NULL, 0, discovery_browse_callback, mesh))) {
411 logger(mesh, MESHLINK_ERROR, "Failed to create discovery service browser: %s\n", catta_strerror(catta_server_errno(mesh->catta_server)));
415 // Start the discovery thread
416 if(pthread_create(&mesh->discovery_thread, NULL, discovery_loop, mesh) != 0) {
417 logger(mesh, MESHLINK_ERROR, "Could not start discovery thread: %s\n", strerror(errno));
418 memset(&mesh->discovery_thread, 0, sizeof(mesh)->discovery_thread);
422 mesh->discovery_threadstarted = true;
428 if(mesh->catta_browser != NULL) {
429 catta_s_service_browser_free(mesh->catta_browser);
430 mesh->catta_browser = NULL;
433 if(mesh->catta_server != NULL) {
434 catta_server_free(mesh->catta_server);
435 mesh->catta_server = NULL;
438 if(mesh->catta_poll != NULL) {
439 catta_simple_poll_free(mesh->catta_poll);
440 mesh->catta_poll = NULL;
443 if(mesh->catta_servicetype != NULL) {
444 free(mesh->catta_servicetype);
445 mesh->catta_servicetype = NULL;
451 void discovery_stop(meshlink_handle_t *mesh) {
452 logger(mesh, MESHLINK_DEBUG, "discovery_stop called\n");
455 assert(mesh != NULL);
458 if(mesh->catta_poll) {
459 catta_simple_poll_quit(mesh->catta_poll);
462 // Wait for the discovery thread to finish
463 if(mesh->discovery_threadstarted == true) {
464 pthread_join(mesh->discovery_thread, NULL);
465 mesh->discovery_threadstarted = false;
468 // Clean up resources
469 if(mesh->catta_browser != NULL) {
470 catta_s_service_browser_free(mesh->catta_browser);
471 mesh->catta_browser = NULL;
474 if(mesh->catta_group) {
475 catta_s_entry_group_reset(mesh->catta_group);
476 catta_s_entry_group_free(mesh->catta_group);
477 mesh->catta_group = NULL;
480 if(mesh->catta_server != NULL) {
481 catta_server_free(mesh->catta_server);
482 mesh->catta_server = NULL;
485 if(mesh->catta_poll != NULL) {
486 catta_simple_poll_free(mesh->catta_poll);
487 mesh->catta_poll = NULL;
490 if(mesh->catta_servicetype != NULL) {
491 free(mesh->catta_servicetype);
492 mesh->catta_servicetype = NULL;