etc/afpd/afp_avahi.c

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