26
26
* along with this program. If not, see
27
27
* <http://www.gnu.org/licenses/>.
29
* Contact the authors at <mandos@recompile.se>.
29
* Contact the authors at <mandos@fukt.bsnet.se>.
32
32
/* Needed by GPGME, specifically gpgme_data_seek() */
33
#ifndef _LARGEFILE_SOURCE
34
33
#define _LARGEFILE_SOURCE
35
#endif /* not _LARGEFILE_SOURCE */
36
#ifndef _FILE_OFFSET_BITS
37
34
#define _FILE_OFFSET_BITS 64
38
#endif /* not _FILE_OFFSET_BITS */
40
36
#define _GNU_SOURCE /* TEMP_FAILURE_RETRY(), asprintf() */
42
38
#include <stdio.h> /* fprintf(), stderr, fwrite(),
44
#include <stdint.h> /* uint16_t, uint32_t, intptr_t */
39
stdout, ferror(), sscanf(),
41
#include <stdint.h> /* uint16_t, uint32_t */
45
42
#include <stddef.h> /* NULL, size_t, ssize_t */
46
#include <stdlib.h> /* free(), EXIT_SUCCESS, srand(),
48
#include <stdbool.h> /* bool, false, true */
43
#include <stdlib.h> /* free(), EXIT_SUCCESS, EXIT_FAILURE,
45
#include <stdbool.h> /* bool, true */
49
46
#include <string.h> /* memset(), strcmp(), strlen(),
50
47
strerror(), asprintf(), strcpy() */
51
#include <sys/ioctl.h> /* ioctl */
48
#include <sys/ioctl.h> /* ioctl */
52
49
#include <sys/types.h> /* socket(), inet_pton(), sockaddr,
53
50
sockaddr_in6, PF_INET6,
54
SOCK_STREAM, uid_t, gid_t, open(),
56
#include <sys/stat.h> /* open(), S_ISREG */
51
SOCK_STREAM, INET6_ADDRSTRLEN,
52
uid_t, gid_t, open(), opendir(),
54
#include <sys/stat.h> /* open() */
57
55
#include <sys/socket.h> /* socket(), struct sockaddr_in6,
58
inet_pton(), connect(),
60
#include <fcntl.h> /* open(), unlinkat() */
56
struct in6_addr, inet_pton(),
58
#include <fcntl.h> /* open() */
61
59
#include <dirent.h> /* opendir(), struct dirent, readdir()
63
#include <inttypes.h> /* PRIu16, PRIdMAX, intmax_t,
65
#include <errno.h> /* perror(), errno,
66
program_invocation_short_name */
67
#include <time.h> /* nanosleep(), time(), sleep() */
61
#include <inttypes.h> /* PRIu16, intmax_t, SCNdMAX */
62
#include <assert.h> /* assert() */
63
#include <errno.h> /* perror(), errno */
64
#include <time.h> /* nanosleep(), time() */
68
65
#include <net/if.h> /* ioctl, ifreq, SIOCGIFFLAGS, IFF_UP,
69
66
SIOCSIFFLAGS, if_indextoname(),
70
67
if_nametoindex(), IF_NAMESIZE */
71
#include <netinet/in.h> /* IN6_IS_ADDR_LINKLOCAL,
72
INET_ADDRSTRLEN, INET6_ADDRSTRLEN
68
#include <netinet/in.h>
74
69
#include <unistd.h> /* close(), SEEK_SET, off_t, write(),
75
getuid(), getgid(), seteuid(),
76
setgid(), pause(), _exit(),
78
#include <arpa/inet.h> /* inet_pton(), htons() */
79
#include <iso646.h> /* not, or, and */
70
getuid(), getgid(), setuid(),
72
#include <arpa/inet.h> /* inet_pton(), htons */
73
#include <iso646.h> /* not, and, or */
80
74
#include <argp.h> /* struct argp_option, error_t, struct
81
75
argp_state, struct argp,
82
76
argp_parse(), ARGP_KEY_ARG,
83
77
ARGP_KEY_END, ARGP_ERR_UNKNOWN */
84
#include <signal.h> /* sigemptyset(), sigaddset(),
85
sigaction(), SIGTERM, sig_atomic_t,
87
#include <sysexits.h> /* EX_OSERR, EX_USAGE, EX_UNAVAILABLE,
88
EX_NOHOST, EX_IOERR, EX_PROTOCOL */
89
#include <sys/wait.h> /* waitpid(), WIFEXITED(),
90
WEXITSTATUS(), WTERMSIG() */
91
#include <grp.h> /* setgroups() */
92
#include <argz.h> /* argz_add_sep(), argz_next(),
93
argz_delete(), argz_append(),
94
argz_stringify(), argz_add(),
96
#include <netdb.h> /* getnameinfo(), NI_NUMERICHOST,
97
EAI_SYSTEM, gai_strerror() */
100
79
#include <sys/klog.h> /* klogctl() */
101
#endif /* __linux__ */
104
83
/* All Avahi types, constants and functions
133
112
#define PATHDIR "/conf/conf.d/mandos"
134
113
#define SECKEY "seckey.txt"
135
114
#define PUBKEY "pubkey.txt"
136
#define HOOKDIR "/lib/mandos/network-hooks.d"
138
116
bool debug = false;
139
117
static const char mandos_protocol_version[] = "1";
140
118
const char *argp_program_version = "mandos-client " VERSION;
141
const char *argp_program_bug_address = "<mandos@recompile.se>";
142
static const char sys_class_net[] = "/sys/class/net";
143
char *connect_to = NULL;
144
const char *hookdir = HOOKDIR;
149
/* Doubly linked list that need to be circularly linked when used */
150
typedef struct server{
153
AvahiIfIndex if_index;
155
struct timespec last_seen;
119
const char *argp_program_bug_address = "<mandos@fukt.bsnet.se>";
160
121
/* Used for passing in values through the Avahi callback functions */
123
AvahiSimplePoll *simple_poll;
162
124
AvahiServer *server;
163
125
gnutls_certificate_credentials_t cred;
164
126
unsigned int dh_bits;
165
127
gnutls_dh_params_t dh_params;
166
128
const char *priority;
168
server *current_server;
170
size_t interfaces_size;
171
130
} mandos_context;
173
/* global so signal handler can reach it*/
174
AvahiSimplePoll *simple_poll;
176
sig_atomic_t quit_now = 0;
177
int signal_received = 0;
179
/* Function to use when printing errors */
180
void perror_plus(const char *print_text){
182
fprintf(stderr, "Mandos plugin %s: ",
183
program_invocation_short_name);
188
__attribute__((format (gnu_printf, 2, 3), nonnull))
189
int fprintf_plus(FILE *stream, const char *format, ...){
191
va_start (ap, format);
193
TEMP_FAILURE_RETRY(fprintf(stream, "Mandos plugin %s: ",
194
program_invocation_short_name));
195
return (int)TEMP_FAILURE_RETRY(vfprintf(stream, format, ap));
199
* Make additional room in "buffer" for at least BUFFER_SIZE more
200
* bytes. "buffer_capacity" is how much is currently allocated,
133
* Make room in "buffer" for at least BUFFER_SIZE additional bytes.
134
* "buffer_capacity" is how much is currently allocated,
201
135
* "buffer_length" is how much is already used.
203
__attribute__((nonnull, warn_unused_result))
204
size_t incbuffer(char **buffer, size_t buffer_length,
205
size_t buffer_capacity){
137
size_t adjustbuffer(char **buffer, size_t buffer_length,
138
size_t buffer_capacity){
206
139
if(buffer_length + BUFFER_SIZE > buffer_capacity){
207
char *new_buf = realloc(*buffer, buffer_capacity + BUFFER_SIZE);
209
int old_errno = errno;
140
*buffer = realloc(*buffer, buffer_capacity + BUFFER_SIZE);
216
144
buffer_capacity += BUFFER_SIZE;
218
146
return buffer_capacity;
221
/* Add server to set of servers to retry periodically */
222
__attribute__((nonnull, warn_unused_result))
223
bool add_server(const char *ip, in_port_t port, AvahiIfIndex if_index,
224
int af, server **current_server){
226
server *new_server = malloc(sizeof(server));
227
if(new_server == NULL){
228
perror_plus("malloc");
231
*new_server = (server){ .ip = strdup(ip),
233
.if_index = if_index,
235
if(new_server->ip == NULL){
236
perror_plus("strdup");
239
ret = clock_gettime(CLOCK_MONOTONIC, &(new_server->last_seen));
241
perror_plus("clock_gettime");
244
/* Special case of first server */
245
if(*current_server == NULL){
246
new_server->next = new_server;
247
new_server->prev = new_server;
248
*current_server = new_server;
250
/* Place the new server last in the list */
251
new_server->next = *current_server;
252
new_server->prev = (*current_server)->prev;
253
new_server->prev->next = new_server;
254
(*current_server)->prev = new_server;
260
150
* Initialize GPGME.
262
__attribute__((nonnull, warn_unused_result))
263
static bool init_gpgme(const char * const seckey,
264
const char * const pubkey,
265
const char * const tempdir,
152
static bool init_gpgme(mandos_context *mc, const char *seckey,
153
const char *pubkey, const char *tempdir){
267
155
gpgme_error_t rc;
268
156
gpgme_engine_info_t engine_info;
271
160
* Helper function to insert pub and seckey to the engine keyring.
273
bool import_key(const char * const filename){
162
bool import_key(const char *filename){
276
164
gpgme_data_t pgp_data;
278
166
fd = (int)TEMP_FAILURE_RETRY(open(filename, O_RDONLY));
284
172
rc = gpgme_data_new_from_fd(&pgp_data, fd);
285
173
if(rc != GPG_ERR_NO_ERROR){
286
fprintf_plus(stderr, "bad gpgme_data_new_from_fd: %s: %s\n",
287
gpgme_strsource(rc), gpgme_strerror(rc));
174
fprintf(stderr, "bad gpgme_data_new_from_fd: %s: %s\n",
175
gpgme_strsource(rc), gpgme_strerror(rc));
291
179
rc = gpgme_op_import(mc->ctx, pgp_data);
292
180
if(rc != GPG_ERR_NO_ERROR){
293
fprintf_plus(stderr, "bad gpgme_op_import: %s: %s\n",
294
gpgme_strsource(rc), gpgme_strerror(rc));
181
fprintf(stderr, "bad gpgme_op_import: %s: %s\n",
182
gpgme_strsource(rc), gpgme_strerror(rc));
298
186
ret = (int)TEMP_FAILURE_RETRY(close(fd));
300
perror_plus("close");
302
190
gpgme_data_release(pgp_data);
307
fprintf_plus(stderr, "Initializing GPGME\n");
195
fprintf(stderr, "Initialize gpgme\n");
311
199
gpgme_check_version(NULL);
312
200
rc = gpgme_engine_check_version(GPGME_PROTOCOL_OpenPGP);
313
201
if(rc != GPG_ERR_NO_ERROR){
314
fprintf_plus(stderr, "bad gpgme_engine_check_version: %s: %s\n",
315
gpgme_strsource(rc), gpgme_strerror(rc));
202
fprintf(stderr, "bad gpgme_engine_check_version: %s: %s\n",
203
gpgme_strsource(rc), gpgme_strerror(rc));
319
/* Set GPGME home directory for the OpenPGP engine only */
207
/* Set GPGME home directory for the OpenPGP engine only */
320
208
rc = gpgme_get_engine_info(&engine_info);
321
209
if(rc != GPG_ERR_NO_ERROR){
322
fprintf_plus(stderr, "bad gpgme_get_engine_info: %s: %s\n",
323
gpgme_strsource(rc), gpgme_strerror(rc));
210
fprintf(stderr, "bad gpgme_get_engine_info: %s: %s\n",
211
gpgme_strsource(rc), gpgme_strerror(rc));
326
214
while(engine_info != NULL){
641
507
__attribute__((unused)) const char *txt){}
643
509
/* Called when a Mandos server is found */
644
__attribute__((nonnull, warn_unused_result))
645
static int start_mandos_communication(const char *ip, in_port_t port,
510
static int start_mandos_communication(const char *ip, uint16_t port,
646
511
AvahiIfIndex if_index,
647
int af, mandos_context *mc){
648
int ret, tcp_sd = -1;
650
struct sockaddr_storage to;
515
union { struct sockaddr in; struct sockaddr_in6 in6; } to;
651
516
char *buffer = NULL;
652
char *decrypted_buffer = NULL;
517
char *decrypted_buffer;
653
518
size_t buffer_length = 0;
654
519
size_t buffer_capacity = 0;
520
ssize_t decrypted_buffer_size;
523
char interface[IF_NAMESIZE];
657
524
gnutls_session_t session;
658
int pf; /* Protocol family */
675
fprintf_plus(stderr, "Bad address family: %d\n", af);
680
/* If the interface is specified and we have a list of interfaces */
681
if(if_index != AVAHI_IF_UNSPEC and mc->interfaces != NULL){
682
/* Check if the interface is one of the interfaces we are using */
685
char *interface = NULL;
686
while((interface=argz_next(mc->interfaces, mc->interfaces_size,
688
if(if_nametoindex(interface) == (unsigned int)if_index){
695
/* This interface does not match any in the list, so we don't
696
connect to the server */
698
char interface[IF_NAMESIZE];
699
if(if_indextoname((unsigned int)if_index, interface) == NULL){
700
perror_plus("if_indextoname");
702
fprintf_plus(stderr, "Skipping server on non-used interface"
704
if_indextoname((unsigned int)if_index,
712
ret = init_gnutls_session(&session, mc);
526
ret = init_gnutls_session(mc, &session);
718
fprintf_plus(stderr, "Setting up a TCP connection to %s, port %"
719
PRIuMAX "\n", ip, (uintmax_t)port);
532
fprintf(stderr, "Setting up a tcp connection to %s, port %" PRIu16
722
tcp_sd = socket(pf, SOCK_STREAM, 0);
536
tcp_sd = socket(PF_INET6, SOCK_STREAM, 0);
725
perror_plus("socket");
543
if(if_indextoname((unsigned int)if_index, interface) == NULL){
544
perror("if_indextoname");
547
fprintf(stderr, "Binding to interface %s\n", interface);
735
550
memset(&to, 0, sizeof(to));
737
((struct sockaddr_in6 *)&to)->sin6_family = (sa_family_t)af;
738
ret = inet_pton(af, ip, &((struct sockaddr_in6 *)&to)->sin6_addr);
740
((struct sockaddr_in *)&to)->sin_family = (sa_family_t)af;
741
ret = inet_pton(af, ip, &((struct sockaddr_in *)&to)->sin_addr);
551
to.in6.sin6_family = AF_INET6;
552
/* It would be nice to have a way to detect if we were passed an
553
IPv4 address here. Now we assume an IPv6 address. */
554
ret = inet_pton(AF_INET6, ip, &to.in6.sin6_addr);
745
perror_plus("inet_pton");
751
fprintf_plus(stderr, "Bad address: %s\n", ip);
756
((struct sockaddr_in6 *)&to)->sin6_port = htons(port);
757
if(IN6_IS_ADDR_LINKLOCAL
758
(&((struct sockaddr_in6 *)&to)->sin6_addr)){
759
if(if_index == AVAHI_IF_UNSPEC){
760
fprintf_plus(stderr, "An IPv6 link-local address is"
761
" incomplete without a network interface\n");
765
/* Set the network interface number as scope */
766
((struct sockaddr_in6 *)&to)->sin6_scope_id = (uint32_t)if_index;
769
((struct sockaddr_in *)&to)->sin_port = htons(port);
560
fprintf(stderr, "Bad address: %s\n", ip);
563
to.in6.sin6_port = htons(port); /* Spurious warnings from
565
-Wunreachable-code */
567
to.in6.sin6_scope_id = (uint32_t)if_index;
778
if(af == AF_INET6 and if_index != AVAHI_IF_UNSPEC){
779
char interface[IF_NAMESIZE];
780
if(if_indextoname((unsigned int)if_index, interface) == NULL){
781
perror_plus("if_indextoname");
783
fprintf_plus(stderr, "Connection to: %s%%%s, port %" PRIuMAX
784
"\n", ip, interface, (uintmax_t)port);
570
fprintf(stderr, "Connection to: %s, port %" PRIu16 "\n", ip,
572
char addrstr[INET6_ADDRSTRLEN] = "";
573
if(inet_ntop(to.in6.sin6_family, &(to.in6.sin6_addr), addrstr,
574
sizeof(addrstr)) == NULL){
577
if(strcmp(addrstr, ip) != 0){
578
fprintf(stderr, "Canonical address form: %s\n", addrstr);
787
fprintf_plus(stderr, "Connection to: %s, port %" PRIuMAX "\n",
788
ip, (uintmax_t)port);
790
char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?
791
INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";
793
ret = getnameinfo((struct sockaddr *)&to,
794
sizeof(struct sockaddr_in6),
795
addrstr, sizeof(addrstr), NULL, 0,
798
ret = getnameinfo((struct sockaddr *)&to,
799
sizeof(struct sockaddr_in),
800
addrstr, sizeof(addrstr), NULL, 0,
803
if(ret == EAI_SYSTEM){
804
perror_plus("getnameinfo");
805
} else if(ret != 0) {
806
fprintf_plus(stderr, "getnameinfo: %s", gai_strerror(ret));
807
} else if(strcmp(addrstr, ip) != 0){
808
fprintf_plus(stderr, "Canonical address form: %s\n", addrstr);
818
ret = connect(tcp_sd, (struct sockaddr *)&to,
819
sizeof(struct sockaddr_in6));
821
ret = connect(tcp_sd, (struct sockaddr *)&to, /* IPv4 */
822
sizeof(struct sockaddr_in));
583
ret = connect(tcp_sd, &to.in, sizeof(to));
825
if((errno != ECONNREFUSED and errno != ENETUNREACH) or debug){
827
perror_plus("connect");
838
589
const char *out = mandos_protocol_version;
1160
815
case AVAHI_BROWSER_ALL_FOR_NOW:
1161
816
case AVAHI_BROWSER_CACHE_EXHAUSTED:
1163
fprintf_plus(stderr, "No Mandos server found, still"
818
fprintf(stderr, "No Mandos server found, still searching...\n");
1170
/* Signal handler that stops main loop after SIGTERM */
1171
static void handle_sigterm(int sig){
1176
signal_received = sig;
1177
int old_errno = errno;
1178
/* set main loop to exit */
1179
if(simple_poll != NULL){
1180
avahi_simple_poll_quit(simple_poll);
1185
__attribute__((nonnull, warn_unused_result))
1186
bool get_flags(const char *ifname, struct ifreq *ifr){
1190
int s = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1193
perror_plus("socket");
1197
strcpy(ifr->ifr_name, ifname);
1198
ret = ioctl(s, SIOCGIFFLAGS, ifr);
1202
perror_plus("ioctl SIOCGIFFLAGS");
1210
__attribute__((nonnull, warn_unused_result))
1211
bool good_flags(const char *ifname, const struct ifreq *ifr){
1213
/* Reject the loopback device */
1214
if(ifr->ifr_flags & IFF_LOOPBACK){
1216
fprintf_plus(stderr, "Rejecting loopback interface \"%s\"\n",
1221
/* Accept point-to-point devices only if connect_to is specified */
1222
if(connect_to != NULL and (ifr->ifr_flags & IFF_POINTOPOINT)){
1224
fprintf_plus(stderr, "Accepting point-to-point interface"
1225
" \"%s\"\n", ifname);
1229
/* Otherwise, reject non-broadcast-capable devices */
1230
if(not (ifr->ifr_flags & IFF_BROADCAST)){
1232
fprintf_plus(stderr, "Rejecting non-broadcast interface"
1233
" \"%s\"\n", ifname);
1237
/* Reject non-ARP interfaces (including dummy interfaces) */
1238
if(ifr->ifr_flags & IFF_NOARP){
1240
fprintf_plus(stderr, "Rejecting non-ARP interface \"%s\"\n",
1246
/* Accept this device */
1248
fprintf_plus(stderr, "Interface \"%s\" is good\n", ifname);
1254
* This function determines if a directory entry in /sys/class/net
1255
* corresponds to an acceptable network device.
1256
* (This function is passed to scandir(3) as a filter function.)
1258
__attribute__((nonnull, warn_unused_result))
1259
int good_interface(const struct dirent *if_entry){
1260
if(if_entry->d_name[0] == '.'){
1265
if(not get_flags(if_entry->d_name, &ifr)){
1267
fprintf_plus(stderr, "Failed to get flags for interface "
1268
"\"%s\"\n", if_entry->d_name);
1273
if(not good_flags(if_entry->d_name, &ifr)){
1280
* This function determines if a network interface is up.
1282
__attribute__((nonnull, warn_unused_result))
1283
bool interface_is_up(const char *interface){
1285
if(not get_flags(interface, &ifr)){
1287
fprintf_plus(stderr, "Failed to get flags for interface "
1288
"\"%s\"\n", interface);
1293
return (bool)(ifr.ifr_flags & IFF_UP);
1297
* This function determines if a network interface is running
1299
__attribute__((nonnull, warn_unused_result))
1300
bool interface_is_running(const char *interface){
1302
if(not get_flags(interface, &ifr)){
1304
fprintf_plus(stderr, "Failed to get flags for interface "
1305
"\"%s\"\n", interface);
1310
return (bool)(ifr.ifr_flags & IFF_RUNNING);
1313
__attribute__((nonnull, pure, warn_unused_result))
1314
int notdotentries(const struct dirent *direntry){
1315
/* Skip "." and ".." */
1316
if(direntry->d_name[0] == '.'
1317
and (direntry->d_name[1] == '\0'
1318
or (direntry->d_name[1] == '.'
1319
and direntry->d_name[2] == '\0'))){
1325
/* Is this directory entry a runnable program? */
1326
__attribute__((nonnull, warn_unused_result))
1327
int runnable_hook(const struct dirent *direntry){
1332
if((direntry->d_name)[0] == '\0'){
1337
sret = strspn(direntry->d_name, "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
1338
"abcdefghijklmnopqrstuvwxyz"
1341
if((direntry->d_name)[sret] != '\0'){
1342
/* Contains non-allowed characters */
1344
fprintf_plus(stderr, "Ignoring hook \"%s\" with bad name\n",
1350
ret = fstatat(hookdir_fd, direntry->d_name, &st, 0);
1353
perror_plus("Could not stat hook");
1357
if(not (S_ISREG(st.st_mode))){
1358
/* Not a regular file */
1360
fprintf_plus(stderr, "Ignoring hook \"%s\" - not a file\n",
1365
if(not (st.st_mode & (S_IXUSR | S_IXGRP | S_IXOTH))){
1366
/* Not executable */
1368
fprintf_plus(stderr, "Ignoring hook \"%s\" - not executable\n",
1374
fprintf_plus(stderr, "Hook \"%s\" is acceptable\n",
1380
__attribute__((nonnull, warn_unused_result))
1381
int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,
1382
mandos_context *mc){
1384
struct timespec now;
1385
struct timespec waited_time;
1386
intmax_t block_time;
1389
if(mc->current_server == NULL){
1391
fprintf_plus(stderr, "Wait until first server is found."
1394
ret = avahi_simple_poll_iterate(s, -1);
1397
fprintf_plus(stderr, "Check current_server if we should run"
1400
/* the current time */
1401
ret = clock_gettime(CLOCK_MONOTONIC, &now);
1403
perror_plus("clock_gettime");
1406
/* Calculating in ms how long time between now and server
1407
who we visted longest time ago. Now - last seen. */
1408
waited_time.tv_sec = (now.tv_sec
1409
- mc->current_server->last_seen.tv_sec);
1410
waited_time.tv_nsec = (now.tv_nsec
1411
- mc->current_server->last_seen.tv_nsec);
1412
/* total time is 10s/10,000ms.
1413
Converting to s from ms by dividing by 1,000,
1414
and ns to ms by dividing by 1,000,000. */
1415
block_time = ((retry_interval
1416
- ((intmax_t)waited_time.tv_sec * 1000))
1417
- ((intmax_t)waited_time.tv_nsec / 1000000));
1420
fprintf_plus(stderr, "Blocking for %" PRIdMAX " ms\n",
1424
if(block_time <= 0){
1425
ret = start_mandos_communication(mc->current_server->ip,
1426
mc->current_server->port,
1427
mc->current_server->if_index,
1428
mc->current_server->af, mc);
1430
avahi_simple_poll_quit(s);
1433
ret = clock_gettime(CLOCK_MONOTONIC,
1434
&mc->current_server->last_seen);
1436
perror_plus("clock_gettime");
1439
mc->current_server = mc->current_server->next;
1440
block_time = 0; /* Call avahi to find new Mandos
1441
servers, but don't block */
1444
ret = avahi_simple_poll_iterate(s, (int)block_time);
1447
if(ret > 0 or errno != EINTR){
1448
return (ret != 1) ? ret : 0;
1454
/* Set effective uid to 0, return errno */
1455
__attribute__((warn_unused_result))
1456
error_t raise_privileges(void){
1457
error_t old_errno = errno;
1458
error_t ret_errno = 0;
1459
if(seteuid(0) == -1){
1461
perror_plus("seteuid");
1467
/* Set effective and real user ID to 0. Return errno. */
1468
__attribute__((warn_unused_result))
1469
error_t raise_privileges_permanently(void){
1470
error_t old_errno = errno;
1471
error_t ret_errno = raise_privileges();
1476
if(setuid(0) == -1){
1478
perror_plus("seteuid");
1484
/* Set effective user ID to unprivileged saved user ID */
1485
__attribute__((warn_unused_result))
1486
error_t lower_privileges(void){
1487
error_t old_errno = errno;
1488
error_t ret_errno = 0;
1489
if(seteuid(uid) == -1){
1491
perror_plus("seteuid");
1497
/* Lower privileges permanently */
1498
__attribute__((warn_unused_result))
1499
error_t lower_privileges_permanently(void){
1500
error_t old_errno = errno;
1501
error_t ret_errno = 0;
1502
if(setuid(uid) == -1){
1504
perror_plus("setuid");
1512
* Based on the example in the GNU LibC manual chapter 13.13 "File
1513
* Descriptor Flags".
1514
| [[info:libc:Descriptor%20Flags][File Descriptor Flags]] |
1516
__attribute__((warn_unused_result))
1517
static int set_cloexec_flag(int fd){
1518
int ret = (int)TEMP_FAILURE_RETRY(fcntl(fd, F_GETFD, 0));
1519
/* If reading the flags failed, return error indication now. */
1523
/* Store modified flag word in the descriptor. */
1524
return (int)TEMP_FAILURE_RETRY(fcntl(fd, F_SETFD,
1527
#endif /* not O_CLOEXEC */
1529
__attribute__((nonnull))
1530
void run_network_hooks(const char *mode, const char *interface,
1532
struct dirent **direntries;
1533
if(hookdir_fd == -1){
1534
hookdir_fd = open(hookdir, O_RDONLY |
1537
#else /* not O_CLOEXEC */
1539
#endif /* not O_CLOEXEC */
1541
if(hookdir_fd == -1){
1542
if(errno == ENOENT){
1544
fprintf_plus(stderr, "Network hook directory \"%s\" not"
1545
" found\n", hookdir);
1548
perror_plus("open");
1553
if(set_cloexec_flag(hookdir_fd) < 0){
1554
perror_plus("set_cloexec_flag");
1555
if((int)TEMP_FAILURE_RETRY(close(hookdir_fd)) == -1){
1556
perror_plus("close");
1562
#endif /* not O_CLOEXEC */
1565
#if __GLIBC_PREREQ(2, 15)
1566
int numhooks = scandirat(hookdir_fd, ".", &direntries,
1567
runnable_hook, alphasort);
1568
#else /* not __GLIBC_PREREQ(2, 15) */
1569
int numhooks = scandir(hookdir, &direntries, runnable_hook,
1571
#endif /* not __GLIBC_PREREQ(2, 15) */
1572
#else /* not __GLIBC__ */
1573
int numhooks = scandir(hookdir, &direntries, runnable_hook,
1575
#endif /* not __GLIBC__ */
1577
perror_plus("scandir");
1580
struct dirent *direntry;
1582
int devnull = open("/dev/null", O_RDONLY);
1583
for(int i = 0; i < numhooks; i++){
1584
direntry = direntries[i];
1586
fprintf_plus(stderr, "Running network hook \"%s\"\n",
1589
pid_t hook_pid = fork();
1592
/* Raise privileges */
1593
if(raise_privileges_permanently() != 0){
1594
perror_plus("Failed to raise privileges");
1601
perror_plus("setgid");
1604
/* Reset supplementary groups */
1606
ret = setgroups(0, NULL);
1608
perror_plus("setgroups");
1611
ret = dup2(devnull, STDIN_FILENO);
1613
perror_plus("dup2(devnull, STDIN_FILENO)");
1616
ret = close(devnull);
1618
perror_plus("close");
1621
ret = dup2(STDERR_FILENO, STDOUT_FILENO);
1623
perror_plus("dup2(STDERR_FILENO, STDOUT_FILENO)");
1626
ret = setenv("MANDOSNETHOOKDIR", hookdir, 1);
1628
perror_plus("setenv");
1631
ret = setenv("DEVICE", interface, 1);
1633
perror_plus("setenv");
1636
ret = setenv("VERBOSITY", debug ? "1" : "0", 1);
1638
perror_plus("setenv");
1641
ret = setenv("MODE", mode, 1);
1643
perror_plus("setenv");
1647
ret = asprintf(&delaystring, "%f", (double)delay);
1649
perror_plus("asprintf");
1652
ret = setenv("DELAY", delaystring, 1);
1655
perror_plus("setenv");
1659
if(connect_to != NULL){
1660
ret = setenv("CONNECT", connect_to, 1);
1662
perror_plus("setenv");
1666
if(fexecve(hookdir_fd, (char *const [])
1667
{ direntry->d_name, NULL }, environ) == -1){
1668
perror_plus("fexecve");
1669
_exit(EXIT_FAILURE);
1673
if(TEMP_FAILURE_RETRY(waitpid(hook_pid, &status, 0)) == -1){
1674
perror_plus("waitpid");
1677
if(WIFEXITED(status)){
1678
if(WEXITSTATUS(status) != 0){
1679
fprintf_plus(stderr, "Warning: network hook \"%s\" exited"
1680
" with status %d\n", direntry->d_name,
1681
WEXITSTATUS(status));
1684
} else if(WIFSIGNALED(status)){
1685
fprintf_plus(stderr, "Warning: network hook \"%s\" died by"
1686
" signal %d\n", direntry->d_name,
1690
fprintf_plus(stderr, "Warning: network hook \"%s\""
1691
" crashed\n", direntry->d_name);
1696
fprintf_plus(stderr, "Network hook \"%s\" ran successfully\n",
1700
if((int)TEMP_FAILURE_RETRY(close(hookdir_fd)) == -1){
1701
perror_plus("close");
1708
__attribute__((nonnull, warn_unused_result))
1709
error_t bring_up_interface(const char *const interface,
1711
error_t old_errno = errno;
1713
struct ifreq network;
1714
unsigned int if_index = if_nametoindex(interface);
1716
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
1726
if(not interface_is_up(interface)){
1727
error_t ret_errno = 0, ioctl_errno = 0;
1728
if(not get_flags(interface, &network)){
1730
fprintf_plus(stderr, "Failed to get flags for interface "
1731
"\"%s\"\n", interface);
1735
network.ifr_flags |= IFF_UP; /* set flag */
1737
int sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1740
perror_plus("socket");
1746
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1748
perror_plus("close");
1755
fprintf_plus(stderr, "Bringing up interface \"%s\"\n",
1759
/* Raise privileges */
1760
ret_errno = raise_privileges();
1762
perror_plus("Failed to raise privileges");
1767
bool restore_loglevel = false;
1769
/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO
1770
messages about the network interface to mess up the prompt */
1771
ret_linux = klogctl(8, NULL, 5);
1772
if(ret_linux == -1){
1773
perror_plus("klogctl");
1775
restore_loglevel = true;
1778
#endif /* __linux__ */
1779
int ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
1780
ioctl_errno = errno;
1782
if(restore_loglevel){
1783
ret_linux = klogctl(7, NULL, 0);
1784
if(ret_linux == -1){
1785
perror_plus("klogctl");
1788
#endif /* __linux__ */
1790
/* If raise_privileges() succeeded above */
1792
/* Lower privileges */
1793
ret_errno = lower_privileges();
1796
perror_plus("Failed to lower privileges");
1800
/* Close the socket */
1801
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1803
perror_plus("close");
1806
if(ret_setflags == -1){
1807
errno = ioctl_errno;
1808
perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");
1813
fprintf_plus(stderr, "Interface \"%s\" is already up; good\n",
1817
/* Sleep checking until interface is running.
1818
Check every 0.25s, up to total time of delay */
1819
for(int i=0; i < delay * 4; i++){
1820
if(interface_is_running(interface)){
1823
struct timespec sleeptime = { .tv_nsec = 250000000 };
1824
ret = nanosleep(&sleeptime, NULL);
1825
if(ret == -1 and errno != EINTR){
1826
perror_plus("nanosleep");
1834
__attribute__((nonnull, warn_unused_result))
1835
error_t take_down_interface(const char *const interface){
1836
error_t old_errno = errno;
1837
struct ifreq network;
1838
unsigned int if_index = if_nametoindex(interface);
1840
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
1844
if(interface_is_up(interface)){
1845
error_t ret_errno = 0, ioctl_errno = 0;
1846
if(not get_flags(interface, &network) and debug){
1848
fprintf_plus(stderr, "Failed to get flags for interface "
1849
"\"%s\"\n", interface);
1853
network.ifr_flags &= ~(short)IFF_UP; /* clear flag */
1855
int sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1858
perror_plus("socket");
1864
fprintf_plus(stderr, "Taking down interface \"%s\"\n",
1868
/* Raise privileges */
1869
ret_errno = raise_privileges();
1871
perror_plus("Failed to raise privileges");
1874
int ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
1875
ioctl_errno = errno;
1877
/* If raise_privileges() succeeded above */
1879
/* Lower privileges */
1880
ret_errno = lower_privileges();
1883
perror_plus("Failed to lower privileges");
1887
/* Close the socket */
1888
int ret = (int)TEMP_FAILURE_RETRY(close(sd));
1890
perror_plus("close");
1893
if(ret_setflags == -1){
1894
errno = ioctl_errno;
1895
perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");
1900
fprintf_plus(stderr, "Interface \"%s\" is already down; odd\n",
1908
824
int main(int argc, char *argv[]){
1909
mandos_context mc = { .server = NULL, .dh_bits = 1024,
1910
.priority = "SECURE256:!CTYPE-X.509:"
1911
"+CTYPE-OPENPGP", .current_server = NULL,
1912
.interfaces = NULL, .interfaces_size = 0 };
1913
825
AvahiSServiceBrowser *sb = NULL;
1916
828
intmax_t tmpmax;
1918
830
int exitcode = EXIT_SUCCESS;
1919
char *interfaces_to_take_down = NULL;
1920
size_t interfaces_to_take_down_size = 0;
1921
char run_tempdir[] = "/run/tmp/mandosXXXXXX";
1922
char old_tempdir[] = "/tmp/mandosXXXXXX";
1923
char *tempdir = NULL;
831
const char *interface = "eth0";
832
struct ifreq network;
836
char *connect_to = NULL;
837
char tempdir[] = "/tmp/mandosXXXXXX";
838
bool tempdir_created = false;
1924
839
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
1925
840
const char *seckey = PATHDIR "/" SECKEY;
1926
841
const char *pubkey = PATHDIR "/" PUBKEY;
1927
char *interfaces_hooks = NULL;
843
mandos_context mc = { .simple_poll = NULL, .server = NULL,
844
.dh_bits = 1024, .priority = "SECURE256"
845
":!CTYPE-X.509:+CTYPE-OPENPGP" };
1929
846
bool gnutls_initialized = false;
1930
847
bool gpgme_initialized = false;
1932
double retry_interval = 10; /* 10s between trying a server and
1933
retrying the same server again */
1935
struct sigaction old_sigterm_action = { .sa_handler = SIG_DFL };
1936
struct sigaction sigterm_action = { .sa_handler = handle_sigterm };
1941
/* Lower any group privileges we might have, just to be safe */
1945
perror_plus("setgid");
1948
/* Lower user privileges (temporarily) */
1952
perror_plus("seteuid");
1960
851
struct argp_option options[] = {
2046
915
mc.priority = arg;
2048
917
case 131: /* --delay */
2050
delay = strtof(arg, &tmp);
2051
if(errno != 0 or tmp == arg or *tmp != '\0'){
2052
argp_error(state, "Bad delay");
2054
case 132: /* --retry */
2056
retry_interval = strtod(arg, &tmp);
2057
if(errno != 0 or tmp == arg or *tmp != '\0'
2058
or (retry_interval * 1000) > INT_MAX
2059
or retry_interval < 0){
2060
argp_error(state, "Bad retry interval");
2063
case 133: /* --network-hook-dir */
2067
* These reproduce what we would get without ARGP_NO_HELP
2069
case '?': /* --help */
2070
argp_state_help(state, state->out_stream,
2071
(ARGP_HELP_STD_HELP | ARGP_HELP_EXIT_ERR)
2072
& ~(unsigned int)ARGP_HELP_EXIT_OK);
2073
case -3: /* --usage */
2074
argp_state_help(state, state->out_stream,
2075
ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);
2076
case 'V': /* --version */
2077
fprintf_plus(state->out_stream, "%s\n", argp_program_version);
2078
exit(argp_err_exit_status);
918
ret = sscanf(arg, "%lf%n", &delay, &numchars);
919
if(ret < 1 or arg[numchars] != '\0'){
920
fprintf(stderr, "Bad delay\n");
2081
929
return ARGP_ERR_UNKNOWN;
2086
934
struct argp argp = { .options = options, .parser = parse_opt,
2088
936
.doc = "Mandos client -- Get and decrypt"
2089
937
" passwords from a Mandos server" };
2090
ret = argp_parse(&argp, argc, argv,
2091
ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);
2098
perror_plus("argp_parse");
2099
exitcode = EX_OSERR;
2102
exitcode = EX_USAGE;
2108
/* Work around Debian bug #633582:
2109
<http://bugs.debian.org/633582> */
2111
/* Re-raise privileges */
2112
ret_errno = raise_privileges();
2115
perror_plus("Failed to raise privileges");
2119
if(strcmp(seckey, PATHDIR "/" SECKEY) == 0){
2120
int seckey_fd = open(seckey, O_RDONLY);
2121
if(seckey_fd == -1){
2122
perror_plus("open");
2124
ret = (int)TEMP_FAILURE_RETRY(fstat(seckey_fd, &st));
2126
perror_plus("fstat");
2128
if(S_ISREG(st.st_mode)
2129
and st.st_uid == 0 and st.st_gid == 0){
2130
ret = fchown(seckey_fd, uid, gid);
2132
perror_plus("fchown");
2136
TEMP_FAILURE_RETRY(close(seckey_fd));
2140
if(strcmp(pubkey, PATHDIR "/" PUBKEY) == 0){
2141
int pubkey_fd = open(pubkey, O_RDONLY);
2142
if(pubkey_fd == -1){
2143
perror_plus("open");
2145
ret = (int)TEMP_FAILURE_RETRY(fstat(pubkey_fd, &st));
2147
perror_plus("fstat");
2149
if(S_ISREG(st.st_mode)
2150
and st.st_uid == 0 and st.st_gid == 0){
2151
ret = fchown(pubkey_fd, uid, gid);
2153
perror_plus("fchown");
2157
TEMP_FAILURE_RETRY(close(pubkey_fd));
2161
/* Lower privileges */
2162
ret_errno = lower_privileges();
2165
perror_plus("Failed to lower privileges");
2170
/* Remove invalid interface names (except "none") */
2172
char *interface = NULL;
2173
while((interface = argz_next(mc.interfaces, mc.interfaces_size,
2175
if(strcmp(interface, "none") != 0
2176
and if_nametoindex(interface) == 0){
2177
if(interface[0] != '\0'){
2178
fprintf_plus(stderr, "Not using nonexisting interface"
2179
" \"%s\"\n", interface);
2181
argz_delete(&mc.interfaces, &mc.interfaces_size, interface);
2187
/* Run network hooks */
2189
if(mc.interfaces != NULL){
2190
interfaces_hooks = malloc(mc.interfaces_size);
2191
if(interfaces_hooks == NULL){
2192
perror_plus("malloc");
938
ret = argp_parse(&argp, argc, argv, 0, 0, NULL);
939
if(ret == ARGP_ERR_UNKNOWN){
940
fprintf(stderr, "Unknown error while parsing arguments\n");
941
exitcode = EXIT_FAILURE;
946
/* If the interface is down, bring it up */
949
/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO
950
messages to mess up the prompt */
951
ret = klogctl(8, NULL, 5);
957
sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
960
exitcode = EXIT_FAILURE;
962
ret = klogctl(7, NULL, 0);
969
strcpy(network.ifr_name, interface);
970
ret = ioctl(sd, SIOCGIFFLAGS, &network);
972
perror("ioctl SIOCGIFFLAGS");
974
ret = klogctl(7, NULL, 0);
979
exitcode = EXIT_FAILURE;
982
if((network.ifr_flags & IFF_UP) == 0){
983
network.ifr_flags |= IFF_UP;
984
ret = ioctl(sd, SIOCSIFFLAGS, &network);
986
perror("ioctl SIOCSIFFLAGS");
987
exitcode = EXIT_FAILURE;
989
ret = klogctl(7, NULL, 0);
2195
memcpy(interfaces_hooks, mc.interfaces, mc.interfaces_size);
2196
argz_stringify(interfaces_hooks, mc.interfaces_size, (int)',');
2198
run_network_hooks("start", interfaces_hooks != NULL ?
2199
interfaces_hooks : "", delay);
2203
avahi_set_log_function(empty_log);
2206
/* Initialize Avahi early so avahi_simple_poll_quit() can be called
2207
from the signal handler */
2208
/* Initialize the pseudo-RNG for Avahi */
2209
srand((unsigned int) time(NULL));
2210
simple_poll = avahi_simple_poll_new();
2211
if(simple_poll == NULL){
2212
fprintf_plus(stderr,
2213
"Avahi: Failed to create simple poll object.\n");
2214
exitcode = EX_UNAVAILABLE;
2218
sigemptyset(&sigterm_action.sa_mask);
2219
ret = sigaddset(&sigterm_action.sa_mask, SIGINT);
2221
perror_plus("sigaddset");
2222
exitcode = EX_OSERR;
2225
ret = sigaddset(&sigterm_action.sa_mask, SIGHUP);
2227
perror_plus("sigaddset");
2228
exitcode = EX_OSERR;
2231
ret = sigaddset(&sigterm_action.sa_mask, SIGTERM);
2233
perror_plus("sigaddset");
2234
exitcode = EX_OSERR;
2237
/* Need to check if the handler is SIG_IGN before handling:
2238
| [[info:libc:Initial Signal Actions]] |
2239
| [[info:libc:Basic Signal Handling]] |
2241
ret = sigaction(SIGINT, NULL, &old_sigterm_action);
2243
perror_plus("sigaction");
2246
if(old_sigterm_action.sa_handler != SIG_IGN){
2247
ret = sigaction(SIGINT, &sigterm_action, NULL);
2249
perror_plus("sigaction");
2250
exitcode = EX_OSERR;
2254
ret = sigaction(SIGHUP, NULL, &old_sigterm_action);
2256
perror_plus("sigaction");
2259
if(old_sigterm_action.sa_handler != SIG_IGN){
2260
ret = sigaction(SIGHUP, &sigterm_action, NULL);
2262
perror_plus("sigaction");
2263
exitcode = EX_OSERR;
2267
ret = sigaction(SIGTERM, NULL, &old_sigterm_action);
2269
perror_plus("sigaction");
2272
if(old_sigterm_action.sa_handler != SIG_IGN){
2273
ret = sigaction(SIGTERM, &sigterm_action, NULL);
2275
perror_plus("sigaction");
2276
exitcode = EX_OSERR;
2281
/* If no interfaces were specified, make a list */
2282
if(mc.interfaces == NULL){
2283
struct dirent **direntries;
2284
/* Look for any good interfaces */
2285
ret = scandir(sys_class_net, &direntries, good_interface,
2288
/* Add all found interfaces to interfaces list */
2289
for(int i = 0; i < ret; ++i){
2290
ret_errno = argz_add(&mc.interfaces, &mc.interfaces_size,
2291
direntries[i]->d_name);
2294
perror_plus("argz_add");
2298
fprintf_plus(stderr, "Will use interface \"%s\"\n",
2299
direntries[i]->d_name);
2305
fprintf_plus(stderr, "Could not find a network interface\n");
2306
exitcode = EXIT_FAILURE;
2311
/* Bring up interfaces which are down, and remove any "none"s */
2313
char *interface = NULL;
2314
while((interface = argz_next(mc.interfaces, mc.interfaces_size,
2316
/* If interface name is "none", stop bringing up interfaces.
2317
Also remove all instances of "none" from the list */
2318
if(strcmp(interface, "none") == 0){
2319
argz_delete(&mc.interfaces, &mc.interfaces_size,
2322
while((interface = argz_next(mc.interfaces,
2323
mc.interfaces_size, interface))){
2324
if(strcmp(interface, "none") == 0){
2325
argz_delete(&mc.interfaces, &mc.interfaces_size,
997
/* sleep checking until interface is running */
998
for(int i=0; i < delay * 4; i++){
999
ret = ioctl(sd, SIOCGIFFLAGS, &network);
1001
perror("ioctl SIOCGIFFLAGS");
1002
} else if(network.ifr_flags & IFF_RUNNING){
2332
bool interface_was_up = interface_is_up(interface);
2333
errno = bring_up_interface(interface, delay);
2334
if(not interface_was_up){
2336
perror_plus("Failed to bring up interface");
2338
errno = argz_add(&interfaces_to_take_down,
2339
&interfaces_to_take_down_size,
2342
perror_plus("argz_add");
1005
struct timespec sleeptime = { .tv_nsec = 250000000 };
1006
ret = nanosleep(&sleeptime, NULL);
1007
if(ret == -1 and errno != EINTR){
1008
perror("nanosleep");
2347
if(debug and (interfaces_to_take_down == NULL)){
2348
fprintf_plus(stderr, "No interfaces were brought up\n");
2352
/* If we only got one interface, explicitly use only that one */
2353
if(argz_count(mc.interfaces, mc.interfaces_size) == 1){
2355
fprintf_plus(stderr, "Using only interface \"%s\"\n",
2358
if_index = (AvahiIfIndex)if_nametoindex(mc.interfaces);
2365
ret = init_gnutls_global(pubkey, seckey, &mc);
2367
fprintf_plus(stderr, "init_gnutls_global failed\n");
2368
exitcode = EX_UNAVAILABLE;
1011
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1016
/* Restores kernel loglevel to default */
1017
ret = klogctl(7, NULL, 0);
1037
ret = init_gnutls_global(&mc, pubkey, seckey);
1039
fprintf(stderr, "init_gnutls_global failed\n");
1040
exitcode = EXIT_FAILURE;
2371
1043
gnutls_initialized = true;
2378
/* Try /run/tmp before /tmp */
2379
tempdir = mkdtemp(run_tempdir);
2380
if(tempdir == NULL and errno == ENOENT){
2382
fprintf_plus(stderr, "Tempdir %s did not work, trying %s\n",
2383
run_tempdir, old_tempdir);
2385
tempdir = mkdtemp(old_tempdir);
2387
if(tempdir == NULL){
2388
perror_plus("mkdtemp");
2396
if(not init_gpgme(pubkey, seckey, tempdir, &mc)){
2397
fprintf_plus(stderr, "init_gpgme failed\n");
2398
exitcode = EX_UNAVAILABLE;
1046
if(mkdtemp(tempdir) == NULL){
1050
tempdir_created = true;
1052
if(not init_gpgme(&mc, pubkey, seckey, tempdir)){
1053
fprintf(stderr, "init_gpgme failed\n");
1054
exitcode = EXIT_FAILURE;
2401
1057
gpgme_initialized = true;
1060
if_index = (AvahiIfIndex) if_nametoindex(interface);
1062
fprintf(stderr, "No such interface: \"%s\"\n", interface);
1063
exitcode = EXIT_FAILURE;