121
133
#define PATHDIR "/conf/conf.d/mandos"
122
134
#define SECKEY "seckey.txt"
123
135
#define PUBKEY "pubkey.txt"
136
#define HOOKDIR "/lib/mandos/network-hooks.d"
125
138
bool debug = false;
126
139
static const char mandos_protocol_version[] = "1";
127
140
const char *argp_program_version = "mandos-client " VERSION;
128
const char *argp_program_bug_address = "<mandos@fukt.bsnet.se>";
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;
130
160
/* Used for passing in values through the Avahi callback functions */
132
AvahiSimplePoll *simple_poll;
133
162
AvahiServer *server;
134
163
gnutls_certificate_credentials_t cred;
135
164
unsigned int dh_bits;
136
165
gnutls_dh_params_t dh_params;
137
166
const char *priority;
168
server *current_server;
170
size_t interfaces_size;
139
171
} mandos_context;
141
/* global context so signal handler can reach it*/
142
mandos_context mc = { .simple_poll = NULL, .server = NULL,
143
.dh_bits = 1024, .priority = "SECURE256"
144
":!CTYPE-X.509:+CTYPE-OPENPGP" };
173
/* global so signal handler can reach it*/
174
AvahiSimplePoll *simple_poll;
146
176
sig_atomic_t quit_now = 0;
147
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));
150
199
* Make additional room in "buffer" for at least BUFFER_SIZE more
151
200
* bytes. "buffer_capacity" is how much is currently allocated,
152
201
* "buffer_length" is how much is already used.
203
__attribute__((nonnull, warn_unused_result))
154
204
size_t incbuffer(char **buffer, size_t buffer_length,
155
size_t buffer_capacity){
205
size_t buffer_capacity){
156
206
if(buffer_length + BUFFER_SIZE > buffer_capacity){
157
*buffer = realloc(*buffer, buffer_capacity + BUFFER_SIZE);
207
char *new_buf = realloc(*buffer, buffer_capacity + BUFFER_SIZE);
209
int old_errno = errno;
161
216
buffer_capacity += BUFFER_SIZE;
163
218
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");
240
ret = clock_gettime(CLOCK_MONOTONIC, &(new_server->last_seen));
242
perror_plus("clock_gettime");
243
free(new_server->ip);
247
/* Special case of first server */
248
if(*current_server == NULL){
249
new_server->next = new_server;
250
new_server->prev = new_server;
251
*current_server = new_server;
253
/* Place the new server last in the list */
254
new_server->next = *current_server;
255
new_server->prev = (*current_server)->prev;
256
new_server->prev->next = new_server;
257
(*current_server)->prev = new_server;
167
263
* Initialize GPGME.
169
static bool init_gpgme(const char *seckey,
170
const char *pubkey, const char *tempdir){
265
__attribute__((nonnull, warn_unused_result))
266
static bool init_gpgme(const char * const seckey,
267
const char * const pubkey,
268
const char * const tempdir,
171
270
gpgme_error_t rc;
172
271
gpgme_engine_info_t engine_info;
176
274
* Helper function to insert pub and seckey to the engine keyring.
178
bool import_key(const char *filename){
276
bool import_key(const char * const filename){
181
279
gpgme_data_t pgp_data;
183
281
fd = (int)TEMP_FAILURE_RETRY(open(filename, O_RDONLY));
189
287
rc = gpgme_data_new_from_fd(&pgp_data, fd);
190
288
if(rc != GPG_ERR_NO_ERROR){
191
fprintf(stderr, "bad gpgme_data_new_from_fd: %s: %s\n",
192
gpgme_strsource(rc), gpgme_strerror(rc));
289
fprintf_plus(stderr, "bad gpgme_data_new_from_fd: %s: %s\n",
290
gpgme_strsource(rc), gpgme_strerror(rc));
196
rc = gpgme_op_import(mc.ctx, pgp_data);
294
rc = gpgme_op_import(mc->ctx, pgp_data);
197
295
if(rc != GPG_ERR_NO_ERROR){
198
fprintf(stderr, "bad gpgme_op_import: %s: %s\n",
199
gpgme_strsource(rc), gpgme_strerror(rc));
296
fprintf_plus(stderr, "bad gpgme_op_import: %s: %s\n",
297
gpgme_strsource(rc), gpgme_strerror(rc));
203
301
ret = (int)TEMP_FAILURE_RETRY(close(fd));
303
perror_plus("close");
207
305
gpgme_data_release(pgp_data);
212
fprintf(stderr, "Initializing GPGME\n");
310
fprintf_plus(stderr, "Initializing GPGME\n");
216
314
gpgme_check_version(NULL);
217
315
rc = gpgme_engine_check_version(GPGME_PROTOCOL_OpenPGP);
218
316
if(rc != GPG_ERR_NO_ERROR){
219
fprintf(stderr, "bad gpgme_engine_check_version: %s: %s\n",
220
gpgme_strsource(rc), gpgme_strerror(rc));
317
fprintf_plus(stderr, "bad gpgme_engine_check_version: %s: %s\n",
318
gpgme_strsource(rc), gpgme_strerror(rc));
224
/* Set GPGME home directory for the OpenPGP engine only */
322
/* Set GPGME home directory for the OpenPGP engine only */
225
323
rc = gpgme_get_engine_info(&engine_info);
226
324
if(rc != GPG_ERR_NO_ERROR){
227
fprintf(stderr, "bad gpgme_get_engine_info: %s: %s\n",
228
gpgme_strsource(rc), gpgme_strerror(rc));
325
fprintf_plus(stderr, "bad gpgme_get_engine_info: %s: %s\n",
326
gpgme_strsource(rc), gpgme_strerror(rc));
231
329
while(engine_info != NULL){
270
372
ssize_t plaintext_length = 0;
273
fprintf(stderr, "Trying to decrypt OpenPGP data\n");
375
fprintf_plus(stderr, "Trying to decrypt OpenPGP data\n");
276
378
/* Create new GPGME data buffer from memory cryptotext */
277
379
rc = gpgme_data_new_from_mem(&dh_crypto, cryptotext, crypto_size,
279
381
if(rc != GPG_ERR_NO_ERROR){
280
fprintf(stderr, "bad gpgme_data_new_from_mem: %s: %s\n",
281
gpgme_strsource(rc), gpgme_strerror(rc));
382
fprintf_plus(stderr, "bad gpgme_data_new_from_mem: %s: %s\n",
383
gpgme_strsource(rc), gpgme_strerror(rc));
285
387
/* Create new empty GPGME data buffer for the plaintext */
286
388
rc = gpgme_data_new(&dh_plain);
287
389
if(rc != GPG_ERR_NO_ERROR){
288
fprintf(stderr, "bad gpgme_data_new: %s: %s\n",
289
gpgme_strsource(rc), gpgme_strerror(rc));
390
fprintf_plus(stderr, "Mandos plugin mandos-client: "
391
"bad gpgme_data_new: %s: %s\n",
392
gpgme_strsource(rc), gpgme_strerror(rc));
290
393
gpgme_data_release(dh_crypto);
294
397
/* Decrypt data from the cryptotext data buffer to the plaintext
296
rc = gpgme_op_decrypt(mc.ctx, dh_crypto, dh_plain);
399
rc = gpgme_op_decrypt(mc->ctx, dh_crypto, dh_plain);
297
400
if(rc != GPG_ERR_NO_ERROR){
298
fprintf(stderr, "bad gpgme_op_decrypt: %s: %s\n",
299
gpgme_strsource(rc), gpgme_strerror(rc));
401
fprintf_plus(stderr, "bad gpgme_op_decrypt: %s: %s\n",
402
gpgme_strsource(rc), gpgme_strerror(rc));
300
403
plaintext_length = -1;
302
405
gpgme_decrypt_result_t result;
303
result = gpgme_op_decrypt_result(mc.ctx);
406
result = gpgme_op_decrypt_result(mc->ctx);
304
407
if(result == NULL){
305
fprintf(stderr, "gpgme_op_decrypt_result failed\n");
408
fprintf_plus(stderr, "gpgme_op_decrypt_result failed\n");
307
fprintf(stderr, "Unsupported algorithm: %s\n",
308
result->unsupported_algorithm);
309
fprintf(stderr, "Wrong key usage: %u\n",
310
result->wrong_key_usage);
410
fprintf_plus(stderr, "Unsupported algorithm: %s\n",
411
result->unsupported_algorithm);
412
fprintf_plus(stderr, "Wrong key usage: %u\n",
413
result->wrong_key_usage);
311
414
if(result->file_name != NULL){
312
fprintf(stderr, "File name: %s\n", result->file_name);
415
fprintf_plus(stderr, "File name: %s\n", result->file_name);
314
417
gpgme_recipient_t recipient;
315
418
recipient = result->recipients;
316
419
while(recipient != NULL){
317
fprintf(stderr, "Public key algorithm: %s\n",
318
gpgme_pubkey_algo_name(recipient->pubkey_algo));
319
fprintf(stderr, "Key ID: %s\n", recipient->keyid);
320
fprintf(stderr, "Secret key available: %s\n",
321
recipient->status == GPG_ERR_NO_SECKEY
420
fprintf_plus(stderr, "Public key algorithm: %s\n",
421
gpgme_pubkey_algo_name
422
(recipient->pubkey_algo));
423
fprintf_plus(stderr, "Key ID: %s\n", recipient->keyid);
424
fprintf_plus(stderr, "Secret key available: %s\n",
425
recipient->status == GPG_ERR_NO_SECKEY
323
427
recipient = recipient->next;
422
529
/* OpenPGP credentials */
423
gnutls_certificate_allocate_credentials(&mc.cred);
530
ret = gnutls_certificate_allocate_credentials(&mc->cred);
424
531
if(ret != GNUTLS_E_SUCCESS){
425
fprintf(stderr, "GnuTLS memory error: %s\n", /* Spurious warning
429
safer_gnutls_strerror(ret));
532
fprintf_plus(stderr, "GnuTLS memory error: %s\n",
533
safer_gnutls_strerror(ret));
430
534
gnutls_global_deinit();
435
fprintf(stderr, "Attempting to use OpenPGP public key %s and"
436
" secret key %s as GnuTLS credentials\n", pubkeyfilename,
539
fprintf_plus(stderr, "Attempting to use OpenPGP public key %s and"
540
" secret key %s as GnuTLS credentials\n",
440
545
ret = gnutls_certificate_set_openpgp_key_file
441
(mc.cred, pubkeyfilename, seckeyfilename,
546
(mc->cred, pubkeyfilename, seckeyfilename,
442
547
GNUTLS_OPENPGP_FMT_BASE64);
443
548
if(ret != GNUTLS_E_SUCCESS){
445
"Error[%d] while reading the OpenPGP key pair ('%s',"
446
" '%s')\n", ret, pubkeyfilename, seckeyfilename);
447
fprintf(stderr, "The GnuTLS error is: %s\n",
448
safer_gnutls_strerror(ret));
550
"Error[%d] while reading the OpenPGP key pair ('%s',"
551
" '%s')\n", ret, pubkeyfilename, seckeyfilename);
552
fprintf_plus(stderr, "The GnuTLS error is: %s\n",
553
safer_gnutls_strerror(ret));
452
557
/* GnuTLS server initialization */
453
ret = gnutls_dh_params_init(&mc.dh_params);
558
ret = gnutls_dh_params_init(&mc->dh_params);
454
559
if(ret != GNUTLS_E_SUCCESS){
455
fprintf(stderr, "Error in GnuTLS DH parameter initialization:"
456
" %s\n", safer_gnutls_strerror(ret));
560
fprintf_plus(stderr, "Error in GnuTLS DH parameter"
561
" initialization: %s\n",
562
safer_gnutls_strerror(ret));
459
ret = gnutls_dh_params_generate2(mc.dh_params, mc.dh_bits);
565
ret = gnutls_dh_params_generate2(mc->dh_params, mc->dh_bits);
460
566
if(ret != GNUTLS_E_SUCCESS){
461
fprintf(stderr, "Error in GnuTLS prime generation: %s\n",
462
safer_gnutls_strerror(ret));
567
fprintf_plus(stderr, "Error in GnuTLS prime generation: %s\n",
568
safer_gnutls_strerror(ret));
466
gnutls_certificate_set_dh_params(mc.cred, mc.dh_params);
572
gnutls_certificate_set_dh_params(mc->cred, mc->dh_params);
472
gnutls_certificate_free_credentials(mc.cred);
578
gnutls_certificate_free_credentials(mc->cred);
473
579
gnutls_global_deinit();
474
gnutls_dh_params_deinit(mc.dh_params);
580
gnutls_dh_params_deinit(mc->dh_params);
478
static int init_gnutls_session(gnutls_session_t *session){
584
__attribute__((nonnull, warn_unused_result))
585
static int init_gnutls_session(gnutls_session_t *session,
480
588
/* GnuTLS session creation */
568
fprintf(stderr, "Bad address family: %d\n", af);
678
fprintf_plus(stderr, "Bad address family: %d\n", af);
572
ret = init_gnutls_session(&session);
683
/* If the interface is specified and we have a list of interfaces */
684
if(if_index != AVAHI_IF_UNSPEC and mc->interfaces != NULL){
685
/* Check if the interface is one of the interfaces we are using */
688
char *interface = NULL;
689
while((interface=argz_next(mc->interfaces, mc->interfaces_size,
691
if(if_nametoindex(interface) == (unsigned int)if_index){
698
/* This interface does not match any in the list, so we don't
699
connect to the server */
701
char interface[IF_NAMESIZE];
702
if(if_indextoname((unsigned int)if_index, interface) == NULL){
703
perror_plus("if_indextoname");
705
fprintf_plus(stderr, "Skipping server on non-used interface"
707
if_indextoname((unsigned int)if_index,
715
ret = init_gnutls_session(&session, mc);
578
fprintf(stderr, "Setting up a TCP connection to %s, port %" PRIu16
721
fprintf_plus(stderr, "Setting up a TCP connection to %s, port %"
722
PRIuMAX "\n", ip, (uintmax_t)port);
582
725
tcp_sd = socket(pf, SOCK_STREAM, 0);
728
perror_plus("socket");
592
738
memset(&to, 0, sizeof(to));
593
739
if(af == AF_INET6){
594
to.in6.sin6_family = (sa_family_t)af;
595
ret = inet_pton(af, ip, &to.in6.sin6_addr);
740
((struct sockaddr_in6 *)&to)->sin6_family = (sa_family_t)af;
741
ret = inet_pton(af, ip, &((struct sockaddr_in6 *)&to)->sin6_addr);
596
742
} else { /* IPv4 */
597
to.in.sin_family = (sa_family_t)af;
598
ret = inet_pton(af, ip, &to.in.sin_addr);
743
((struct sockaddr_in *)&to)->sin_family = (sa_family_t)af;
744
ret = inet_pton(af, ip, &((struct sockaddr_in *)&to)->sin_addr);
748
perror_plus("inet_pton");
605
fprintf(stderr, "Bad address: %s\n", ip);
754
fprintf_plus(stderr, "Bad address: %s\n", ip);
608
758
if(af == AF_INET6){
609
to.in6.sin6_port = htons(port); /* Spurious warnings from
611
-Wunreachable-code */
613
if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */
614
(&to.in6.sin6_addr)){ /* -Wstrict-aliasing=2 or lower and
759
((struct sockaddr_in6 *)&to)->sin6_port = htons(port);
760
if(IN6_IS_ADDR_LINKLOCAL
761
(&((struct sockaddr_in6 *)&to)->sin6_addr)){
616
762
if(if_index == AVAHI_IF_UNSPEC){
617
fprintf(stderr, "An IPv6 link-local address is incomplete"
618
" without a network interface\n");
763
fprintf_plus(stderr, "An IPv6 link-local address is"
764
" incomplete without a network interface\n");
621
768
/* Set the network interface number as scope */
622
to.in6.sin6_scope_id = (uint32_t)if_index;
769
((struct sockaddr_in6 *)&to)->sin6_scope_id = (uint32_t)if_index;
625
to.in.sin_port = htons(port); /* Spurious warnings from
627
-Wunreachable-code */
772
((struct sockaddr_in *)&to)->sin_port = htons(port);
970
1179
signal_received = sig;
971
1180
int old_errno = errno;
972
if(mc.simple_poll != NULL){
973
avahi_simple_poll_quit(mc.simple_poll);
1181
/* set main loop to exit */
1182
if(simple_poll != NULL){
1183
avahi_simple_poll_quit(simple_poll);
1188
__attribute__((nonnull, warn_unused_result))
1189
bool get_flags(const char *ifname, struct ifreq *ifr){
1193
int s = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1196
perror_plus("socket");
1200
strcpy(ifr->ifr_name, ifname);
1201
ret = ioctl(s, SIOCGIFFLAGS, ifr);
1205
perror_plus("ioctl SIOCGIFFLAGS");
1213
__attribute__((nonnull, warn_unused_result))
1214
bool good_flags(const char *ifname, const struct ifreq *ifr){
1216
/* Reject the loopback device */
1217
if(ifr->ifr_flags & IFF_LOOPBACK){
1219
fprintf_plus(stderr, "Rejecting loopback interface \"%s\"\n",
1224
/* Accept point-to-point devices only if connect_to is specified */
1225
if(connect_to != NULL and (ifr->ifr_flags & IFF_POINTOPOINT)){
1227
fprintf_plus(stderr, "Accepting point-to-point interface"
1228
" \"%s\"\n", ifname);
1232
/* Otherwise, reject non-broadcast-capable devices */
1233
if(not (ifr->ifr_flags & IFF_BROADCAST)){
1235
fprintf_plus(stderr, "Rejecting non-broadcast interface"
1236
" \"%s\"\n", ifname);
1240
/* Reject non-ARP interfaces (including dummy interfaces) */
1241
if(ifr->ifr_flags & IFF_NOARP){
1243
fprintf_plus(stderr, "Rejecting non-ARP interface \"%s\"\n",
1249
/* Accept this device */
1251
fprintf_plus(stderr, "Interface \"%s\" is good\n", ifname);
1257
* This function determines if a directory entry in /sys/class/net
1258
* corresponds to an acceptable network device.
1259
* (This function is passed to scandir(3) as a filter function.)
1261
__attribute__((nonnull, warn_unused_result))
1262
int good_interface(const struct dirent *if_entry){
1263
if(if_entry->d_name[0] == '.'){
1268
if(not get_flags(if_entry->d_name, &ifr)){
1270
fprintf_plus(stderr, "Failed to get flags for interface "
1271
"\"%s\"\n", if_entry->d_name);
1276
if(not good_flags(if_entry->d_name, &ifr)){
1283
* This function determines if a network interface is up.
1285
__attribute__((nonnull, warn_unused_result))
1286
bool interface_is_up(const char *interface){
1288
if(not get_flags(interface, &ifr)){
1290
fprintf_plus(stderr, "Failed to get flags for interface "
1291
"\"%s\"\n", interface);
1296
return (bool)(ifr.ifr_flags & IFF_UP);
1300
* This function determines if a network interface is running
1302
__attribute__((nonnull, warn_unused_result))
1303
bool interface_is_running(const char *interface){
1305
if(not get_flags(interface, &ifr)){
1307
fprintf_plus(stderr, "Failed to get flags for interface "
1308
"\"%s\"\n", interface);
1313
return (bool)(ifr.ifr_flags & IFF_RUNNING);
1316
__attribute__((nonnull, pure, warn_unused_result))
1317
int notdotentries(const struct dirent *direntry){
1318
/* Skip "." and ".." */
1319
if(direntry->d_name[0] == '.'
1320
and (direntry->d_name[1] == '\0'
1321
or (direntry->d_name[1] == '.'
1322
and direntry->d_name[2] == '\0'))){
1328
/* Is this directory entry a runnable program? */
1329
__attribute__((nonnull, warn_unused_result))
1330
int runnable_hook(const struct dirent *direntry){
1335
if((direntry->d_name)[0] == '\0'){
1340
sret = strspn(direntry->d_name, "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
1341
"abcdefghijklmnopqrstuvwxyz"
1344
if((direntry->d_name)[sret] != '\0'){
1345
/* Contains non-allowed characters */
1347
fprintf_plus(stderr, "Ignoring hook \"%s\" with bad name\n",
1353
ret = fstatat(hookdir_fd, direntry->d_name, &st, 0);
1356
perror_plus("Could not stat hook");
1360
if(not (S_ISREG(st.st_mode))){
1361
/* Not a regular file */
1363
fprintf_plus(stderr, "Ignoring hook \"%s\" - not a file\n",
1368
if(not (st.st_mode & (S_IXUSR | S_IXGRP | S_IXOTH))){
1369
/* Not executable */
1371
fprintf_plus(stderr, "Ignoring hook \"%s\" - not executable\n",
1377
fprintf_plus(stderr, "Hook \"%s\" is acceptable\n",
1383
__attribute__((nonnull, warn_unused_result))
1384
int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,
1385
mandos_context *mc){
1387
struct timespec now;
1388
struct timespec waited_time;
1389
intmax_t block_time;
1392
if(mc->current_server == NULL){
1394
fprintf_plus(stderr, "Wait until first server is found."
1397
ret = avahi_simple_poll_iterate(s, -1);
1400
fprintf_plus(stderr, "Check current_server if we should run"
1403
/* the current time */
1404
ret = clock_gettime(CLOCK_MONOTONIC, &now);
1406
perror_plus("clock_gettime");
1409
/* Calculating in ms how long time between now and server
1410
who we visted longest time ago. Now - last seen. */
1411
waited_time.tv_sec = (now.tv_sec
1412
- mc->current_server->last_seen.tv_sec);
1413
waited_time.tv_nsec = (now.tv_nsec
1414
- mc->current_server->last_seen.tv_nsec);
1415
/* total time is 10s/10,000ms.
1416
Converting to s from ms by dividing by 1,000,
1417
and ns to ms by dividing by 1,000,000. */
1418
block_time = ((retry_interval
1419
- ((intmax_t)waited_time.tv_sec * 1000))
1420
- ((intmax_t)waited_time.tv_nsec / 1000000));
1423
fprintf_plus(stderr, "Blocking for %" PRIdMAX " ms\n",
1427
if(block_time <= 0){
1428
ret = start_mandos_communication(mc->current_server->ip,
1429
mc->current_server->port,
1430
mc->current_server->if_index,
1431
mc->current_server->af, mc);
1433
avahi_simple_poll_quit(s);
1436
ret = clock_gettime(CLOCK_MONOTONIC,
1437
&mc->current_server->last_seen);
1439
perror_plus("clock_gettime");
1442
mc->current_server = mc->current_server->next;
1443
block_time = 0; /* Call avahi to find new Mandos
1444
servers, but don't block */
1447
ret = avahi_simple_poll_iterate(s, (int)block_time);
1450
if(ret > 0 or errno != EINTR){
1451
return (ret != 1) ? ret : 0;
1457
/* Set effective uid to 0, return errno */
1458
__attribute__((warn_unused_result))
1459
error_t raise_privileges(void){
1460
error_t old_errno = errno;
1461
error_t ret_errno = 0;
1462
if(seteuid(0) == -1){
1469
/* Set effective and real user ID to 0. Return errno. */
1470
__attribute__((warn_unused_result))
1471
error_t raise_privileges_permanently(void){
1472
error_t old_errno = errno;
1473
error_t ret_errno = raise_privileges();
1478
if(setuid(0) == -1){
1485
/* Set effective user ID to unprivileged saved user ID */
1486
__attribute__((warn_unused_result))
1487
error_t lower_privileges(void){
1488
error_t old_errno = errno;
1489
error_t ret_errno = 0;
1490
if(seteuid(uid) == -1){
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){
1509
__attribute__((nonnull))
1510
void run_network_hooks(const char *mode, const char *interface,
1512
struct dirent **direntries = NULL;
1513
if(hookdir_fd == -1){
1514
hookdir_fd = open(hookdir, O_RDONLY);
1515
if(hookdir_fd == -1){
1516
if(errno == ENOENT){
1518
fprintf_plus(stderr, "Network hook directory \"%s\" not"
1519
" found\n", hookdir);
1522
perror_plus("open");
1528
#if __GLIBC_PREREQ(2, 15)
1529
int numhooks = scandirat(hookdir_fd, ".", &direntries,
1530
runnable_hook, alphasort);
1531
#else /* not __GLIBC_PREREQ(2, 15) */
1532
int numhooks = scandir(hookdir, &direntries, runnable_hook,
1534
#endif /* not __GLIBC_PREREQ(2, 15) */
1535
#else /* not __GLIBC__ */
1536
int numhooks = scandir(hookdir, &direntries, runnable_hook,
1538
#endif /* not __GLIBC__ */
1540
perror_plus("scandir");
1543
struct dirent *direntry;
1545
int devnull = open("/dev/null", O_RDONLY);
1546
for(int i = 0; i < numhooks; i++){
1547
direntry = direntries[i];
1549
fprintf_plus(stderr, "Running network hook \"%s\"\n",
1552
pid_t hook_pid = fork();
1555
/* Raise privileges */
1556
errno = raise_privileges_permanently();
1558
perror_plus("Failed to raise privileges");
1565
perror_plus("setgid");
1568
/* Reset supplementary groups */
1570
ret = setgroups(0, NULL);
1572
perror_plus("setgroups");
1575
ret = dup2(devnull, STDIN_FILENO);
1577
perror_plus("dup2(devnull, STDIN_FILENO)");
1580
ret = close(devnull);
1582
perror_plus("close");
1585
ret = dup2(STDERR_FILENO, STDOUT_FILENO);
1587
perror_plus("dup2(STDERR_FILENO, STDOUT_FILENO)");
1590
ret = setenv("MANDOSNETHOOKDIR", hookdir, 1);
1592
perror_plus("setenv");
1595
ret = setenv("DEVICE", interface, 1);
1597
perror_plus("setenv");
1600
ret = setenv("VERBOSITY", debug ? "1" : "0", 1);
1602
perror_plus("setenv");
1605
ret = setenv("MODE", mode, 1);
1607
perror_plus("setenv");
1611
ret = asprintf(&delaystring, "%f", (double)delay);
1613
perror_plus("asprintf");
1616
ret = setenv("DELAY", delaystring, 1);
1619
perror_plus("setenv");
1623
if(connect_to != NULL){
1624
ret = setenv("CONNECT", connect_to, 1);
1626
perror_plus("setenv");
1630
int hook_fd = openat(hookdir_fd, direntry->d_name, O_RDONLY);
1632
perror_plus("openat");
1633
_exit(EXIT_FAILURE);
1635
if((int)TEMP_FAILURE_RETRY(close(hookdir_fd)) == -1){
1636
perror_plus("close");
1637
_exit(EXIT_FAILURE);
1639
if(fexecve(hook_fd, (char *const []){ direntry->d_name, NULL },
1641
perror_plus("fexecve");
1642
_exit(EXIT_FAILURE);
1646
if(TEMP_FAILURE_RETRY(waitpid(hook_pid, &status, 0)) == -1){
1647
perror_plus("waitpid");
1650
if(WIFEXITED(status)){
1651
if(WEXITSTATUS(status) != 0){
1652
fprintf_plus(stderr, "Warning: network hook \"%s\" exited"
1653
" with status %d\n", direntry->d_name,
1654
WEXITSTATUS(status));
1657
} else if(WIFSIGNALED(status)){
1658
fprintf_plus(stderr, "Warning: network hook \"%s\" died by"
1659
" signal %d\n", direntry->d_name,
1663
fprintf_plus(stderr, "Warning: network hook \"%s\""
1664
" crashed\n", direntry->d_name);
1669
fprintf_plus(stderr, "Network hook \"%s\" ran successfully\n",
1674
if((int)TEMP_FAILURE_RETRY(close(hookdir_fd)) == -1){
1675
perror_plus("close");
1682
__attribute__((nonnull, warn_unused_result))
1683
error_t bring_up_interface(const char *const interface,
1685
error_t old_errno = errno;
1687
struct ifreq network;
1688
unsigned int if_index = if_nametoindex(interface);
1690
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
1700
if(not interface_is_up(interface)){
1701
error_t ret_errno = 0, ioctl_errno = 0;
1702
if(not get_flags(interface, &network)){
1704
fprintf_plus(stderr, "Failed to get flags for interface "
1705
"\"%s\"\n", interface);
1709
network.ifr_flags |= IFF_UP; /* set flag */
1711
int sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1714
perror_plus("socket");
1720
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1722
perror_plus("close");
1729
fprintf_plus(stderr, "Bringing up interface \"%s\"\n",
1733
/* Raise privileges */
1734
ret_errno = raise_privileges();
1737
perror_plus("Failed to raise privileges");
1742
bool restore_loglevel = false;
1744
/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO
1745
messages about the network interface to mess up the prompt */
1746
ret_linux = klogctl(8, NULL, 5);
1747
if(ret_linux == -1){
1748
perror_plus("klogctl");
1750
restore_loglevel = true;
1753
#endif /* __linux__ */
1754
int ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
1755
ioctl_errno = errno;
1757
if(restore_loglevel){
1758
ret_linux = klogctl(7, NULL, 0);
1759
if(ret_linux == -1){
1760
perror_plus("klogctl");
1763
#endif /* __linux__ */
1765
/* If raise_privileges() succeeded above */
1767
/* Lower privileges */
1768
ret_errno = lower_privileges();
1771
perror_plus("Failed to lower privileges");
1775
/* Close the socket */
1776
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1778
perror_plus("close");
1781
if(ret_setflags == -1){
1782
errno = ioctl_errno;
1783
perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");
1788
fprintf_plus(stderr, "Interface \"%s\" is already up; good\n",
1792
/* Sleep checking until interface is running.
1793
Check every 0.25s, up to total time of delay */
1794
for(int i=0; i < delay * 4; i++){
1795
if(interface_is_running(interface)){
1798
struct timespec sleeptime = { .tv_nsec = 250000000 };
1799
ret = nanosleep(&sleeptime, NULL);
1800
if(ret == -1 and errno != EINTR){
1801
perror_plus("nanosleep");
1809
__attribute__((nonnull, warn_unused_result))
1810
error_t take_down_interface(const char *const interface){
1811
error_t old_errno = errno;
1812
struct ifreq network;
1813
unsigned int if_index = if_nametoindex(interface);
1815
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
1819
if(interface_is_up(interface)){
1820
error_t ret_errno = 0, ioctl_errno = 0;
1821
if(not get_flags(interface, &network) and debug){
1823
fprintf_plus(stderr, "Failed to get flags for interface "
1824
"\"%s\"\n", interface);
1828
network.ifr_flags &= ~(short)IFF_UP; /* clear flag */
1830
int sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1833
perror_plus("socket");
1839
fprintf_plus(stderr, "Taking down interface \"%s\"\n",
1843
/* Raise privileges */
1844
ret_errno = raise_privileges();
1847
perror_plus("Failed to raise privileges");
1850
int ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
1851
ioctl_errno = errno;
1853
/* If raise_privileges() succeeded above */
1855
/* Lower privileges */
1856
ret_errno = lower_privileges();
1859
perror_plus("Failed to lower privileges");
1863
/* Close the socket */
1864
int ret = (int)TEMP_FAILURE_RETRY(close(sd));
1866
perror_plus("close");
1869
if(ret_setflags == -1){
1870
errno = ioctl_errno;
1871
perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");
1876
fprintf_plus(stderr, "Interface \"%s\" is already down; odd\n",
978
1884
int main(int argc, char *argv[]){
1885
mandos_context mc = { .server = NULL, .dh_bits = 1024,
1886
.priority = "SECURE256:!CTYPE-X.509:"
1887
"+CTYPE-OPENPGP", .current_server = NULL,
1888
.interfaces = NULL, .interfaces_size = 0 };
979
1889
AvahiSServiceBrowser *sb = NULL;
982
1892
intmax_t tmpmax;
984
1894
int exitcode = EXIT_SUCCESS;
985
const char *interface = "eth0";
986
struct ifreq network;
988
bool take_down_interface = false;
991
char *connect_to = NULL;
992
char tempdir[] = "/tmp/mandosXXXXXX";
993
bool tempdir_created = false;
1895
char *interfaces_to_take_down = NULL;
1896
size_t interfaces_to_take_down_size = 0;
1897
char run_tempdir[] = "/run/tmp/mandosXXXXXX";
1898
char old_tempdir[] = "/tmp/mandosXXXXXX";
1899
char *tempdir = NULL;
994
1900
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
995
1901
const char *seckey = PATHDIR "/" SECKEY;
996
1902
const char *pubkey = PATHDIR "/" PUBKEY;
1903
char *interfaces_hooks = NULL;
998
1905
bool gnutls_initialized = false;
999
1906
bool gpgme_initialized = false;
1000
1907
float delay = 2.5f;
1908
double retry_interval = 10; /* 10s between trying a server and
1909
retrying the same server again */
1002
1911
struct sigaction old_sigterm_action = { .sa_handler = SIG_DFL };
1003
1912
struct sigaction sigterm_action = { .sa_handler = handle_sigterm };
1189
2217
ret = sigaction(SIGINT, NULL, &old_sigterm_action);
1191
perror("sigaction");
1192
return EXIT_FAILURE;
2219
perror_plus("sigaction");
1194
2222
if(old_sigterm_action.sa_handler != SIG_IGN){
1195
2223
ret = sigaction(SIGINT, &sigterm_action, NULL);
1197
perror("sigaction");
1198
exitcode = EXIT_FAILURE;
2225
perror_plus("sigaction");
2226
exitcode = EX_OSERR;
1202
2230
ret = sigaction(SIGHUP, NULL, &old_sigterm_action);
1204
perror("sigaction");
1205
return EXIT_FAILURE;
2232
perror_plus("sigaction");
1207
2235
if(old_sigterm_action.sa_handler != SIG_IGN){
1208
2236
ret = sigaction(SIGHUP, &sigterm_action, NULL);
1210
perror("sigaction");
1211
exitcode = EXIT_FAILURE;
2238
perror_plus("sigaction");
2239
exitcode = EX_OSERR;
1215
2243
ret = sigaction(SIGTERM, NULL, &old_sigterm_action);
1217
perror("sigaction");
1218
return EXIT_FAILURE;
2245
perror_plus("sigaction");
1220
2248
if(old_sigterm_action.sa_handler != SIG_IGN){
1221
2249
ret = sigaction(SIGTERM, &sigterm_action, NULL);
1223
perror("sigaction");
1224
exitcode = EXIT_FAILURE;
1229
/* If the interface is down, bring it up */
1230
if(interface[0] != '\0'){
1231
if_index = (AvahiIfIndex) if_nametoindex(interface);
1233
fprintf(stderr, "No such interface: \"%s\"\n", interface);
1234
exitcode = EXIT_FAILURE;
1242
/* Re-raise priviliges */
1250
/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO
1251
messages about the network interface to mess up the prompt */
1252
ret = klogctl(8, NULL, 5);
1253
bool restore_loglevel = true;
1255
restore_loglevel = false;
1258
#endif /* __linux__ */
1260
sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1263
exitcode = EXIT_FAILURE;
1265
if(restore_loglevel){
1266
ret = klogctl(7, NULL, 0);
1271
#endif /* __linux__ */
1272
/* Lower privileges */
1280
strcpy(network.ifr_name, interface);
1281
ret = ioctl(sd, SIOCGIFFLAGS, &network);
1283
perror("ioctl SIOCGIFFLAGS");
1285
if(restore_loglevel){
1286
ret = klogctl(7, NULL, 0);
1291
#endif /* __linux__ */
1292
exitcode = EXIT_FAILURE;
1293
/* Lower privileges */
1301
if((network.ifr_flags & IFF_UP) == 0){
1302
network.ifr_flags |= IFF_UP;
1303
take_down_interface = true;
1304
ret = ioctl(sd, SIOCSIFFLAGS, &network);
1306
take_down_interface = false;
1307
perror("ioctl SIOCSIFFLAGS");
1308
exitcode = EXIT_FAILURE;
1310
if(restore_loglevel){
1311
ret = klogctl(7, NULL, 0);
2251
perror_plus("sigaction");
2252
exitcode = EX_OSERR;
2257
/* If no interfaces were specified, make a list */
2258
if(mc.interfaces == NULL){
2259
struct dirent **direntries = NULL;
2260
/* Look for any good interfaces */
2261
ret = scandir(sys_class_net, &direntries, good_interface,
2264
/* Add all found interfaces to interfaces list */
2265
for(int i = 0; i < ret; ++i){
2266
ret_errno = argz_add(&mc.interfaces, &mc.interfaces_size,
2267
direntries[i]->d_name);
2270
perror_plus("argz_add");
2274
fprintf_plus(stderr, "Will use interface \"%s\"\n",
2275
direntries[i]->d_name);
2283
fprintf_plus(stderr, "Could not find a network interface\n");
2284
exitcode = EXIT_FAILURE;
2289
/* Bring up interfaces which are down, and remove any "none"s */
2291
char *interface = NULL;
2292
while((interface = argz_next(mc.interfaces, mc.interfaces_size,
2294
/* If interface name is "none", stop bringing up interfaces.
2295
Also remove all instances of "none" from the list */
2296
if(strcmp(interface, "none") == 0){
2297
argz_delete(&mc.interfaces, &mc.interfaces_size,
2300
while((interface = argz_next(mc.interfaces,
2301
mc.interfaces_size, interface))){
2302
if(strcmp(interface, "none") == 0){
2303
argz_delete(&mc.interfaces, &mc.interfaces_size,
1316
#endif /* __linux__ */
1317
/* Lower privileges */
1326
/* sleep checking until interface is running */
1327
for(int i=0; i < delay * 4; i++){
1328
ret = ioctl(sd, SIOCGIFFLAGS, &network);
1330
perror("ioctl SIOCGIFFLAGS");
1331
} else if(network.ifr_flags & IFF_RUNNING){
1334
struct timespec sleeptime = { .tv_nsec = 250000000 };
1335
ret = nanosleep(&sleeptime, NULL);
1336
if(ret == -1 and errno != EINTR){
1337
perror("nanosleep");
1340
if(not take_down_interface){
1341
/* We won't need the socket anymore */
1342
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1348
if(restore_loglevel){
1349
/* Restores kernel loglevel to default */
1350
ret = klogctl(7, NULL, 0);
1355
#endif /* __linux__ */
1356
/* Lower privileges */
1358
if(take_down_interface){
1359
/* Lower privileges */
1365
/* Lower privileges permanently */
2310
bool interface_was_up = interface_is_up(interface);
2311
errno = bring_up_interface(interface, delay);
2312
if(not interface_was_up){
2314
perror_plus("Failed to bring up interface");
2316
errno = argz_add(&interfaces_to_take_down,
2317
&interfaces_to_take_down_size,
2320
perror_plus("argz_add");
2325
if(debug and (interfaces_to_take_down == NULL)){
2326
fprintf_plus(stderr, "No interfaces were brought up\n");
2330
/* If we only got one interface, explicitly use only that one */
2331
if(argz_count(mc.interfaces, mc.interfaces_size) == 1){
2333
fprintf_plus(stderr, "Using only interface \"%s\"\n",
2336
if_index = (AvahiIfIndex)if_nametoindex(mc.interfaces);
1377
ret = init_gnutls_global(pubkey, seckey);
2343
ret = init_gnutls_global(pubkey, seckey, &mc);
1379
fprintf(stderr, "init_gnutls_global failed\n");
1380
exitcode = EXIT_FAILURE;
2345
fprintf_plus(stderr, "init_gnutls_global failed\n");
2346
exitcode = EX_UNAVAILABLE;
1383
2349
gnutls_initialized = true;
1545
2543
gpgme_release(mc.ctx);
1548
/* Take down the network interface */
1549
if(take_down_interface){
1550
/* Re-raise priviliges */
1557
ret = ioctl(sd, SIOCGIFFLAGS, &network);
1559
perror("ioctl SIOCGIFFLAGS");
1560
} else if(network.ifr_flags & IFF_UP) {
1561
network.ifr_flags &= ~(short)IFF_UP; /* clear flag */
1562
ret = ioctl(sd, SIOCSIFFLAGS, &network);
1564
perror("ioctl SIOCSIFFLAGS");
1567
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1571
/* Lower privileges permanently */
1580
/* Removes the temp directory used by GPGME */
1581
if(tempdir_created){
1583
struct dirent *direntry;
1584
d = opendir(tempdir);
1586
if(errno != ENOENT){
1591
direntry = readdir(d);
1592
if(direntry == NULL){
1595
/* Skip "." and ".." */
1596
if(direntry->d_name[0] == '.'
1597
and (direntry->d_name[1] == '\0'
1598
or (direntry->d_name[1] == '.'
1599
and direntry->d_name[2] == '\0'))){
1602
char *fullname = NULL;
1603
ret = asprintf(&fullname, "%s/%s", tempdir,
1609
ret = remove(fullname);
1611
fprintf(stderr, "remove(\"%s\"): %s\n", fullname,
1618
ret = rmdir(tempdir);
1619
if(ret == -1 and errno != ENOENT){
2546
/* Cleans up the circular linked list of Mandos servers the client
2548
if(mc.current_server != NULL){
2549
mc.current_server->prev->next = NULL;
2550
while(mc.current_server != NULL){
2551
server *next = mc.current_server->next;
2552
free(mc.current_server);
2553
mc.current_server = next;
2557
/* Re-raise privileges */
2559
ret_errno = raise_privileges();
2562
perror_plus("Failed to raise privileges");
2565
/* Run network hooks */
2566
run_network_hooks("stop", interfaces_hooks != NULL ?
2567
interfaces_hooks : "", delay);
2569
/* Take down the network interfaces which were brought up */
2571
char *interface = NULL;
2572
while((interface=argz_next(interfaces_to_take_down,
2573
interfaces_to_take_down_size,
2575
ret_errno = take_down_interface(interface);
2578
perror_plus("Failed to take down interface");
2581
if(debug and (interfaces_to_take_down == NULL)){
2582
fprintf_plus(stderr, "No interfaces needed to be taken"
2588
ret_errno = lower_privileges_permanently();
2591
perror_plus("Failed to lower privileges permanently");
2595
free(interfaces_to_take_down);
2596
free(interfaces_hooks);
2598
/* Removes the GPGME temp directory and all files inside */
2599
if(tempdir != NULL){
2600
struct dirent **direntries = NULL;
2601
int tempdir_fd = (int)TEMP_FAILURE_RETRY(open(tempdir, O_RDONLY |
2603
if(tempdir_fd == -1){
2604
perror_plus("open");
2607
#if __GLIBC_PREREQ(2, 15)
2608
int numentries = scandirat(tempdir_fd, ".", &direntries,
2609
notdotentries, alphasort);
2610
#else /* not __GLIBC_PREREQ(2, 15) */
2611
int numentries = scandir(tempdir, &direntries, notdotentries,
2613
#endif /* not __GLIBC_PREREQ(2, 15) */
2614
#else /* not __GLIBC__ */
2615
int numentries = scandir(tempdir, &direntries, notdotentries,
2617
#endif /* not __GLIBC__ */
2618
if(numentries >= 0){
2619
for(int i = 0; i < numentries; i++){
2620
ret = unlinkat(tempdir_fd, direntries[i]->d_name, 0);
2622
fprintf_plus(stderr, "unlinkat(open(\"%s\", O_RDONLY),"
2623
" \"%s\", 0): %s\n", tempdir,
2624
direntries[i]->d_name, strerror(errno));
2628
/* need to clean even if 0 because man page doesn't specify */
2630
if(numentries == -1){
2631
perror_plus("scandir");
2633
ret = rmdir(tempdir);
2634
if(ret == -1 and errno != ENOENT){
2635
perror_plus("rmdir");
2638
TEMP_FAILURE_RETRY(close(tempdir_fd));