etc/afpd/afp_avahi.c

   1 /*
   2  * Author:  Daniel S. Haischt <me@daniel.stefan.haischt.name>
   3  * Purpose: Avahi based Zeroconf support
   4  * Docs:    http://avahi.org/download/doxygen/
   5  *
   6  */
   7
   8 #ifdef HAVE_CONFIG_H
   9 #include <config.h>
  10 #endif
  11
  12 #ifdef HAVE_AVAHI
  13
  14 #include <unistd.h>
  15
  16 #include <avahi-common/strlst.h>
  17
  18 #include <atalk/logger.h>
  19 #include <atalk/util.h>
  20 #include <atalk/dsi.h>
  21 #include <atalk/unicode.h>
  22
  23 #include "afp_avahi.h"
  24 #include "afp_config.h"
  25 #include "volume.h"
  26
  27 /*****************************************************************
  28  * Global variables
  29  *****************************************************************/
  30 struct context *ctx = NULL;
  31
  32 /*****************************************************************
  33  * Private functions
  34  *****************************************************************/
  35
  36 static void publish_reply(AvahiEntryGroup *g,
  37                           AvahiEntryGroupState state,
  38                           void *userdata);
  39
  40 /*
  41  * This function tries to register the AFP DNS
  42  * SRV service type.
  43  */
  44 static void register_stuff(void) {
  45     uint port;
  46     const AFPConfig *config;
  47     const struct vol *volume;
  48     DSI *dsi;
  49     char name[MAXINSTANCENAMELEN+1];
  50     AvahiStringList *strlist = NULL;
  51     char tmpname[256];
  52
  53     assert(ctx->client);
  54
  55     if (!ctx->group) {
  56         if (!(ctx->group = avahi_entry_group_new(ctx->client, publish_reply, ctx))) {
  57             LOG(log_error, logtype_afpd, "Failed to create entry group: %s",
  58                 avahi_strerror(avahi_client_errno(ctx->client)));
  59             goto fail;
  60         }
  61     }
  62
  63     if (avahi_entry_group_is_empty(ctx->group)) {
  64         /* Register our service */
  65
  66         /* Build AFP volumes list */
  67         int i = 0;
  68         strlist = avahi_string_list_add_printf(strlist, "sys=waMa=0,adVF=0x100");
  69
  70         for (volume = getvolumes(); volume; volume = volume->v_next) {
  71
  72             if (convert_string(CH_UCS2, CH_UTF8_MAC, volume->v_name, -1, tmpname, 255) <= 0) {
  73                 LOG ( log_error, logtype_afpd, "Could not set Zeroconf volume name for TimeMachine");
  74                 goto fail;
  75             }
  76
  77             if (volume->v_flags & AFPVOL_TM) {
  78                 if (volume->v_uuid) {
  79                     LOG(log_info, logtype_afpd, "Registering volume '%s' with UUID: '%s' for TimeMachine",
  80                         volume->v_localname, volume->v_uuid);
  81                     strlist = avahi_string_list_add_printf(strlist, "dk%u=adVN=%s,adVF=0xa1,adVU=%s",
  82                                                            i++, tmpname, volume->v_uuid);
  83                 } else {
  84                     LOG(log_warning, logtype_afpd, "Registering volume '%s' for TimeMachine. But UUID is invalid.",
  85                         volume->v_localname);
  86                     strlist = avahi_string_list_add_printf(strlist, "dk%u=adVN=%s,adVF=0xa1",
  87                                                            i++, tmpname);
  88                 }
  89             }
  90         }
  91
  92         /* AFP server */
  93         for (config = ctx->configs; config; config = config->next) {
  94
  95             dsi = (DSI *)config->obj.handle;
  96             port = getip_port((struct sockaddr *)&dsi->server);
  97
  98             if (convert_string(config->obj.options.unixcharset, CH_UTF8,
  99                                config->obj.options.server ? config->obj.options.server : config->obj.options.hostname, -1,
 100                                name, MAXINSTANCENAMELEN) <= 0) {
 101                 LOG ( log_error, logtype_afpd, "Could not set Zeroconf instance name");
 102                 goto fail;
 103             }
 104
 105             if (avahi_entry_group_add_service(ctx->group,
 106                                               AVAHI_IF_UNSPEC,
 107                                               AVAHI_PROTO_UNSPEC,
 108                                               0,
 109                                               name,
 110                                               AFP_DNS_SERVICE_TYPE,
 111                                               NULL,
 112                                               NULL,
 113                                               port,
 114                                               NULL) < 0) {
 115                 LOG(log_error, logtype_afpd, "Failed to add service: %s",
 116                     avahi_strerror(avahi_client_errno(ctx->client)));
 117                 goto fail;
 118             }
 119
 120             if (i && avahi_entry_group_add_service_strlst(ctx->group,
 121                                                           AVAHI_IF_UNSPEC,
 122                                                           AVAHI_PROTO_UNSPEC,
 123                                                           0,
 124                                                           name,
 125                                                           ADISK_SERVICE_TYPE,
 126                                                           NULL,
 127                                                           NULL,
 128                                                           9, /* discard */
 129                                                           strlist) < 0) {
 130                 LOG(log_error, logtype_afpd, "Failed to add service: %s",
 131                     avahi_strerror(avahi_client_errno(ctx->client)));
 132                 goto fail;
 133             }   /* if */
 134         }       /* for config*/
 135
 136         if (avahi_entry_group_commit(ctx->group) < 0) {
 137             LOG(log_error, logtype_afpd, "Failed to commit entry group: %s",
 138                 avahi_strerror(avahi_client_errno(ctx->client)));
 139             goto fail;
 140         }
 141
 142     }   /* if avahi_entry_group_is_empty*/
 143
 144     return;
 145
 146 fail:
 147     avahi_client_free (ctx->client);
 148     avahi_threaded_poll_quit(ctx->threaded_poll);
 149 }
 150
 151 /* Called when publishing of service data completes */
 152 static void publish_reply(AvahiEntryGroup *g,
 153                           AvahiEntryGroupState state,
 154                           AVAHI_GCC_UNUSED void *userdata)
 155 {
 156     assert(ctx->group == NULL || g == ctx->group);
 157
 158     switch (state) {
 159
 160     case AVAHI_ENTRY_GROUP_ESTABLISHED :
 161         /* The entry group has been established successfully */
 162         LOG(log_debug, logtype_afpd, "publish_reply: AVAHI_ENTRY_GROUP_ESTABLISHED");
 163         break;
 164
 165     case AVAHI_ENTRY_GROUP_COLLISION:
 166         /* With multiple names there's no way to know which one collided */
 167         LOG(log_error, logtype_afpd, "publish_reply: AVAHI_ENTRY_GROUP_COLLISION",
 168             avahi_strerror(avahi_client_errno(ctx->client)));
 169         avahi_client_free(avahi_entry_group_get_client(g));
 170         avahi_threaded_poll_quit(ctx->threaded_poll);
 171         break;
 172
 173     case AVAHI_ENTRY_GROUP_FAILURE:
 174         LOG(log_error, logtype_afpd, "Failed to register service: %s",
 175             avahi_strerror(avahi_client_errno(ctx->client)));
 176         avahi_client_free(avahi_entry_group_get_client(g));
 177         avahi_threaded_poll_quit(ctx->threaded_poll);
 178         break;
 179
 180     case AVAHI_ENTRY_GROUP_UNCOMMITED:
 181         break;
 182     case AVAHI_ENTRY_GROUP_REGISTERING:
 183         break;
 184     }
 185 }
 186
 187 static void client_callback(AvahiClient *client,
 188                             AvahiClientState state,
 189                             void *userdata)
 190 {
 191     ctx->client = client;
 192
 193     switch (state) {
 194     case AVAHI_CLIENT_S_RUNNING:
 195         /* The server has startup successfully and registered its host
 196          * name on the network, so it's time to create our services */
 197         if (!ctx->group)
 198             register_stuff();
 199         break;
 200
 201     case AVAHI_CLIENT_S_COLLISION:
 202         if (ctx->group)
 203             avahi_entry_group_reset(ctx->group);
 204         break;
 205
 206     case AVAHI_CLIENT_FAILURE: {
 207         if (avahi_client_errno(client) == AVAHI_ERR_DISCONNECTED) {
 208             int error;
 209
 210             avahi_client_free(ctx->client);
 211             ctx->client = NULL;
 212             ctx->group = NULL;
 213
 214             /* Reconnect to the server */
 215             if (!(ctx->client = avahi_client_new(avahi_threaded_poll_get(ctx->threaded_poll),
 216                                                  AVAHI_CLIENT_NO_FAIL,
 217                                                  client_callback,
 218                                                  ctx,
 219                                                  &error))) {
 220
 221                 LOG(log_error, logtype_afpd, "Failed to contact server: %s",
 222                     avahi_strerror(error));
 223
 224                 avahi_client_free (ctx->client);
 225                 avahi_threaded_poll_quit(ctx->threaded_poll);
 226             }
 227
 228         } else {
 229             LOG(log_error, logtype_afpd, "Client failure: %s",
 230                 avahi_strerror(avahi_client_errno(client)));
 231             avahi_client_free (ctx->client);
 232             avahi_threaded_poll_quit(ctx->threaded_poll);
 233         }
 234         break;
 235     }
 236
 237     case AVAHI_CLIENT_S_REGISTERING:
 238         break;
 239     case AVAHI_CLIENT_CONNECTING:
 240         break;
 241     }
 242 }
 243
 244 /************************************************************************
 245  * Public funcions
 246  ************************************************************************/
 247
 248 /*
 249  * Tries to setup the Zeroconf thread and any
 250  * neccessary config setting.
 251  */
 252 void av_zeroconf_setup(const AFPConfig *configs) {
 253     int error;
 254
 255     /* initialize the struct that holds our config settings. */
 256     if (ctx) {
 257         LOG(log_debug, logtype_afpd, "Resetting zeroconf records");
 258         avahi_entry_group_reset(ctx->group);
 259     } else {
 260         ctx = calloc(1, sizeof(struct context));
 261         ctx->configs = configs;
 262         assert(ctx);
 263     }
 264
 265 /* first of all we need to initialize our threading env */
 266     if (!(ctx->threaded_poll = avahi_threaded_poll_new())) {
 267         goto fail;
 268     }
 269
 270 /* now we need to acquire a client */
 271     if (!(ctx->client = avahi_client_new(avahi_threaded_poll_get(ctx->threaded_poll),
 272                                          AVAHI_CLIENT_NO_FAIL,
 273                                          client_callback,
 274                                          NULL,
 275                                          &error))) {
 276         LOG(log_error, logtype_afpd, "Failed to create client object: %s",
 277             avahi_strerror(avahi_client_errno(ctx->client)));
 278         goto fail;
 279     }
 280
 281     return;
 282
 283 fail:
 284     if (ctx)
 285         av_zeroconf_unregister();
 286
 287     return;
 288 }
 289
 290 /*
 291  * This function finally runs the loop impl.
 292  */
 293 int av_zeroconf_run(void) {
 294     /* Finally, start the event loop thread */
 295     if (avahi_threaded_poll_start(ctx->threaded_poll) < 0) {
 296         LOG(log_error, logtype_afpd, "Failed to create thread: %s",
 297             avahi_strerror(avahi_client_errno(ctx->client)));
 298         goto fail;
 299     } else {
 300         LOG(log_info, logtype_afpd, "Successfully started avahi loop.");
 301     }
 302
 303     ctx->thread_running = 1;
 304     return 0;
 305
 306 fail:
 307     if (ctx)
 308         av_zeroconf_unregister();
 309
 310     return -1;
 311 }
 312
 313 /*
 314  * Tries to shutdown this loop impl.
 315  * Call this function from outside this thread.
 316  */
 317 void av_zeroconf_shutdown() {
 318     /* Call this when the app shuts down */
 319     avahi_threaded_poll_stop(ctx->threaded_poll);
 320     avahi_client_free(ctx->client);
 321     avahi_threaded_poll_free(ctx->threaded_poll);
 322     free(ctx);
 323     ctx = NULL;
 324 }
 325
 326 /*
 327  * Tries to shutdown this loop impl.
 328  * Call this function from inside this thread.
 329  */
 330 int av_zeroconf_unregister() {
 331     if (ctx->thread_running) {
 332         /* First, block the event loop */
 333         avahi_threaded_poll_lock(ctx->threaded_poll);
 334
 335         /* Than, do your stuff */
 336         avahi_threaded_poll_quit(ctx->threaded_poll);
 337
 338         /* Finally, unblock the event loop */
 339         avahi_threaded_poll_unlock(ctx->threaded_poll);
 340         ctx->thread_running = 0;
 341     }
 342
 343     if (ctx->client)
 344         avahi_client_free(ctx->client);
 345
 346     if (ctx->threaded_poll)
 347         avahi_threaded_poll_free(ctx->threaded_poll);
 348
 349     free(ctx);
 350     ctx = NULL;
 351
 352     return 0;
 353 }
 354
 355 #endif /* USE_AVAHI */
 356