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
entry_group_callback(AvahiServer * s,AVAHI_GCC_UNUSED AvahiSEntryGroup * eg,AvahiEntryGroupState state,void * userdata)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
static_host_new(void)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
static_host_free(StaticHost * s)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
static_host_find(const char * host,const AvahiAddress * a)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
add_static_host_to_server(StaticHost * h)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
remove_static_host_from_server(StaticHost * h)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
static_hosts_add_to_server(void)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
static_hosts_remove_from_server(void)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
static_hosts_load(int in_chroot)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
static_hosts_free_all(void)274 void static_hosts_free_all (void)
275 {
276 while(hosts)
277 static_host_free(hosts);
278 }
279