Home | History | Annotate | Download | only in avahi-daemon 
      1 /***
      2   This file is part of avahi.
      3 
      4   avahi is free software; you can redistribute it and/or modify it
      5   under the terms of the GNU Lesser General Public License as
      6   published by the Free Software Foundation; either version 2.1 of the
      7   License, or (at your option) any later version.
      8 
      9   avahi is distributed in the hope that it will be useful, but WITHOUT
     10   ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
     11   or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General
     12   Public License for more details.
     13 
     14   You should have received a copy of the GNU Lesser General Public
     15   License along with avahi; if not, write to the Free Software
     16   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
     17   USA.
     18 ***/
     19 
     20 #ifdef HAVE_CONFIG_H
     21 #include <config.h>
     22 #endif
     23 
     24 #include <string.h>
     25 #include <errno.h>
     26 #include <stdio.h>
     27 
     28 #include <avahi-common/llist.h>
     29 #include "avahi-common/avahi-malloc.h"
     30 #include <avahi-common/error.h>
     31 #include <avahi-core/log.h>
     32 #include <avahi-core/publish.h>
     33 
     34 #include "main.h"
     35 #include "static-hosts.h"
     36 
     37 typedef struct StaticHost StaticHost;
     38 
     39 struct StaticHost {
     40     AvahiSEntryGroup *group;
     41     int iteration;
     42 
     43     char *host;
     44     AvahiAddress address;
     45 
     46     AVAHI_LLIST_FIELDS(StaticHost, hosts);
     47 };
     48 
     49 static AVAHI_LLIST_HEAD(StaticHost, hosts) = NULL;
     50 static int current_iteration = 0;
     51 
     52 static void add_static_host_to_server(StaticHost *h);
     53 static void remove_static_host_from_server(StaticHost *h);
     54 
     55 static void entry_group_callback(AvahiServer *s, AVAHI_GCC_UNUSED AvahiSEntryGroup *eg, AvahiEntryGroupState state, void* userdata) {
     56     StaticHost *h;
     57 
     58     assert(s);
     59     assert(eg);
     60 
     61     h = userdata;
     62 
     63     switch (state) {
     64 
     65         case AVAHI_ENTRY_GROUP_COLLISION:
     66             avahi_log_error("Host name conflict for \"%s\", not established.", h->host);
     67             break;
     68 
     69         case AVAHI_ENTRY_GROUP_ESTABLISHED:
     70             avahi_log_notice ("Static host name \"%s\" successfully established.", h->host);
     71             break;
     72 
     73         case AVAHI_ENTRY_GROUP_FAILURE:
     74             avahi_log_notice ("Failed to establish static host name \"%s\": %s.", h->host, avahi_strerror (avahi_server_errno (s)));
     75             break;
     76 
     77         case AVAHI_ENTRY_GROUP_UNCOMMITED:
     78         case AVAHI_ENTRY_GROUP_REGISTERING:
     79             ;
     80     }
     81 }
     82 
     83 static StaticHost *static_host_new(void) {
     84     StaticHost *s;
     85 
     86     s = avahi_new(StaticHost, 1);
     87 
     88     s->group = NULL;
     89     s->host = NULL;
     90     s->iteration = current_iteration;
     91 
     92     AVAHI_LLIST_PREPEND(StaticHost, hosts, hosts, s);
     93 
     94     return s;
     95 }
     96 
     97 static void static_host_free(StaticHost *s) {
     98     assert(s);
     99 
    100     AVAHI_LLIST_REMOVE(StaticHost, hosts, hosts, s);
    101 
    102     if (s->group)
    103         avahi_s_entry_group_free (s->group);
    104 
    105     avahi_free(s->host);
    106 
    107     avahi_free(s);
    108 }
    109 
    110 static StaticHost *static_host_find(const char *host, const AvahiAddress *a) {
    111     StaticHost *h;
    112 
    113     assert(host);
    114     assert(a);
    115 
    116     for (h = hosts; h; h = h->hosts_next)
    117         if (!strcmp(h->host, host) && !avahi_address_cmp(a, &h->address))
    118             return h;
    119 
    120     return NULL;
    121 }
    122 
    123 static void add_static_host_to_server(StaticHost *h)
    124 {
    125 
    126     if (!h->group)
    127         if (!(h->group = avahi_s_entry_group_new (avahi_server, entry_group_callback, h))) {
    128             avahi_log_error("avahi_s_entry_group_new() failed: %s", avahi_strerror(avahi_server_errno(avahi_server)));
    129             return;
    130         }
    131 
    132     if (avahi_s_entry_group_is_empty(h->group)) {
    133         AvahiProtocol p;
    134         int err;
    135         const AvahiServerConfig *config;
    136         config = avahi_server_get_config(avahi_server);
    137 
    138         p = (h->address.proto == AVAHI_PROTO_INET && config->publish_a_on_ipv6) ||
    139             (h->address.proto == AVAHI_PROTO_INET6 && config->publish_aaaa_on_ipv4) ? AVAHI_PROTO_UNSPEC : h->address.proto;
    140 
    141         if ((err = avahi_server_add_address(avahi_server, h->group, AVAHI_IF_UNSPEC, p, 0, h->host, &h->address)) < 0) {
    142             avahi_log_error ("Static host name %s: avahi_server_add_address failure: %s", h->host, avahi_strerror(err));
    143             return;
    144         }
    145 
    146         avahi_s_entry_group_commit (h->group);
    147     }
    148 }
    149 
    150 static void remove_static_host_from_server(StaticHost *h)
    151 {
    152     if (h->group)
    153         avahi_s_entry_group_reset (h->group);
    154 }
    155 
    156 void static_hosts_add_to_server(void) {
    157     StaticHost *h;
    158 
    159     for (h = hosts; h; h = h->hosts_next)
    160         add_static_host_to_server(h);
    161 }
    162 
    163 void static_hosts_remove_from_server(void) {
    164     StaticHost *h;
    165 
    166     for (h = hosts; h; h = h->hosts_next)
    167         remove_static_host_from_server(h);
    168 }
    169 
    170 void static_hosts_load(int in_chroot) {
    171     FILE *f;
    172     unsigned int line = 0;
    173     StaticHost *h, *next;
    174     const char *filename = AVAHI_HOSTS_FILE;
    175 
    176     if (!(f = fopen(filename, "r"))) {
    177         if (errno != ENOENT)
    178             avahi_log_error ("Failed to open static hosts file: %s", strerror (errno));
    179         return;
    180     }
    181 
    182     current_iteration++;
    183 
    184     while (!feof(f)) {
    185         unsigned int len;
    186         char ln[256], *s;
    187         char *host, *ip;
    188         AvahiAddress a;
    189 
    190         if (!fgets(ln, sizeof (ln), f))
    191             break;
    192 
    193         line++;
    194 
    195         /* Find the start of the line, ignore whitespace */
    196         s = ln + strspn(ln, " \t");
    197         /* Set the end of the string to NULL */
    198         s[strcspn(s, "#\r\n")] = 0;
    199 
    200         /* Ignore blank lines */
    201         if (*s == 0)
    202             continue;
    203 
    204         /* Read the first string (ip) up to the next whitespace */
    205         len = strcspn(s, " \t");
    206         ip = avahi_strndup(s, len);
    207 
    208         /* Skip past it */
    209         s += len;
    210 
    211         /* Find the next token */
    212         s += strspn(s, " \t");
    213         len = strcspn(s, " \t");
    214         host = avahi_strndup(s, len);
    215 
    216         if (*host == 0)
    217         {
    218             avahi_log_error("%s:%d: Error, unexpected end of line!", filename, line);
    219             avahi_free(host);
    220             avahi_free(ip);
    221             goto fail;
    222         }
    223 
    224         /* Skip over the host */
    225         s += len;
    226 
    227         /* Skip past any more spaces */
    228         s += strspn(s, " \t");
    229 
    230         /* Anything left? */
    231         if (*s != 0) {
    232             avahi_log_error ("%s:%d: Junk on the end of the line!", filename, line);
    233             avahi_free(host);
    234             avahi_free(ip);
    235             goto fail;
    236         }
    237 
    238         if (!avahi_address_parse(ip, AVAHI_PROTO_UNSPEC, &a)) {
    239             avahi_log_error("Static host name %s: failed to parse address %s", host, ip);
    240             avahi_free(host);
    241             avahi_free(ip);
    242             goto fail;
    243         }
    244 
    245         avahi_free(ip);
    246 
    247         if ((h = static_host_find(host, &a)))
    248             avahi_free(host);
    249         else {
    250             h = static_host_new();
    251             h->host = host;
    252             h->address = a;
    253 
    254             avahi_log_info("Loading new static hostname %s.", h->host);
    255         }
    256 
    257         h->iteration = current_iteration;
    258     }
    259 
    260     for (h = hosts; h; h = next) {
    261         next = h->hosts_next;
    262 
    263         if (h->iteration != current_iteration) {
    264             avahi_log_info("Static hostname %s vanished, removing.", h->host);
    265             static_host_free(h);
    266         }
    267     }
    268 
    269 fail:
    270 
    271     fclose(f);
    272 }
    273 
    274 void static_hosts_free_all (void)
    275 {
    276     while(hosts)
    277         static_host_free(hosts);
    278 }
    279