122
133
#define PATHDIR "/conf/conf.d/mandos"
123
134
#define SECKEY "seckey.txt"
124
135
#define PUBKEY "pubkey.txt"
136
#define HOOKDIR "/lib/mandos/network-hooks.d"
126
138
bool debug = false;
127
139
static const char mandos_protocol_version[] = "1";
128
140
const char *argp_program_version = "mandos-client " VERSION;
129
const char *argp_program_bug_address = "<mandos@fukt.bsnet.se>";
141
const char *argp_program_bug_address = "<mandos@recompile.se>";
130
142
static const char sys_class_net[] = "/sys/class/net";
131
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;
133
160
/* Used for passing in values through the Avahi callback functions */
135
AvahiSimplePoll *simple_poll;
136
162
AvahiServer *server;
137
163
gnutls_certificate_credentials_t cred;
138
164
unsigned int dh_bits;
139
165
gnutls_dh_params_t dh_params;
140
166
const char *priority;
168
server *current_server;
170
size_t interfaces_size;
142
171
} mandos_context;
144
/* global context so signal handler can reach it*/
145
mandos_context mc = { .simple_poll = NULL, .server = NULL,
146
.dh_bits = 1024, .priority = "SECURE256"
147
":!CTYPE-X.509:+CTYPE-OPENPGP" };
173
/* global so signal handler can reach it*/
174
AvahiSimplePoll *simple_poll;
149
176
sig_atomic_t quit_now = 0;
150
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));
153
199
* Make additional room in "buffer" for at least BUFFER_SIZE more
154
200
* bytes. "buffer_capacity" is how much is currently allocated,
155
201
* "buffer_length" is how much is already used.
203
__attribute__((nonnull, warn_unused_result))
157
204
size_t incbuffer(char **buffer, size_t buffer_length,
158
size_t buffer_capacity){
205
size_t buffer_capacity){
159
206
if(buffer_length + BUFFER_SIZE > buffer_capacity){
160
*buffer = realloc(*buffer, buffer_capacity + BUFFER_SIZE);
207
char *new_buf = realloc(*buffer, buffer_capacity + BUFFER_SIZE);
209
int old_errno = errno;
164
216
buffer_capacity += BUFFER_SIZE;
166
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");
244
#pragma GCC diagnostic push
245
#pragma GCC diagnostic ignored "-Wcast-qual"
247
free((char *)(new_server->ip));
249
#pragma GCC diagnostic pop
254
/* Special case of first server */
255
if(*current_server == NULL){
256
new_server->next = new_server;
257
new_server->prev = new_server;
258
*current_server = new_server;
260
/* Place the new server last in the list */
261
new_server->next = *current_server;
262
new_server->prev = (*current_server)->prev;
263
new_server->prev->next = new_server;
264
(*current_server)->prev = new_server;
170
270
* Initialize GPGME.
172
static bool init_gpgme(const char *seckey,
173
const char *pubkey, const char *tempdir){
272
__attribute__((nonnull, warn_unused_result))
273
static bool init_gpgme(const char * const seckey,
274
const char * const pubkey,
275
const char * const tempdir,
174
277
gpgme_error_t rc;
175
278
gpgme_engine_info_t engine_info;
179
281
* Helper function to insert pub and seckey to the engine keyring.
181
bool import_key(const char *filename){
283
bool import_key(const char * const filename){
184
286
gpgme_data_t pgp_data;
186
288
fd = (int)TEMP_FAILURE_RETRY(open(filename, O_RDONLY));
192
294
rc = gpgme_data_new_from_fd(&pgp_data, fd);
193
295
if(rc != GPG_ERR_NO_ERROR){
194
fprintf(stderr, "bad gpgme_data_new_from_fd: %s: %s\n",
195
gpgme_strsource(rc), gpgme_strerror(rc));
296
fprintf_plus(stderr, "bad gpgme_data_new_from_fd: %s: %s\n",
297
gpgme_strsource(rc), gpgme_strerror(rc));
199
rc = gpgme_op_import(mc.ctx, pgp_data);
301
rc = gpgme_op_import(mc->ctx, pgp_data);
200
302
if(rc != GPG_ERR_NO_ERROR){
201
fprintf(stderr, "bad gpgme_op_import: %s: %s\n",
202
gpgme_strsource(rc), gpgme_strerror(rc));
303
fprintf_plus(stderr, "bad gpgme_op_import: %s: %s\n",
304
gpgme_strsource(rc), gpgme_strerror(rc));
206
308
ret = (int)TEMP_FAILURE_RETRY(close(fd));
310
perror_plus("close");
210
312
gpgme_data_release(pgp_data);
215
fprintf(stderr, "Initializing GPGME\n");
317
fprintf_plus(stderr, "Initializing GPGME\n");
219
321
gpgme_check_version(NULL);
220
322
rc = gpgme_engine_check_version(GPGME_PROTOCOL_OpenPGP);
221
323
if(rc != GPG_ERR_NO_ERROR){
222
fprintf(stderr, "bad gpgme_engine_check_version: %s: %s\n",
223
gpgme_strsource(rc), gpgme_strerror(rc));
324
fprintf_plus(stderr, "bad gpgme_engine_check_version: %s: %s\n",
325
gpgme_strsource(rc), gpgme_strerror(rc));
227
/* Set GPGME home directory for the OpenPGP engine only */
329
/* Set GPGME home directory for the OpenPGP engine only */
228
330
rc = gpgme_get_engine_info(&engine_info);
229
331
if(rc != GPG_ERR_NO_ERROR){
230
fprintf(stderr, "bad gpgme_get_engine_info: %s: %s\n",
231
gpgme_strsource(rc), gpgme_strerror(rc));
332
fprintf_plus(stderr, "bad gpgme_get_engine_info: %s: %s\n",
333
gpgme_strsource(rc), gpgme_strerror(rc));
234
336
while(engine_info != NULL){
273
379
ssize_t plaintext_length = 0;
276
fprintf(stderr, "Trying to decrypt OpenPGP data\n");
382
fprintf_plus(stderr, "Trying to decrypt OpenPGP data\n");
279
385
/* Create new GPGME data buffer from memory cryptotext */
280
386
rc = gpgme_data_new_from_mem(&dh_crypto, cryptotext, crypto_size,
282
388
if(rc != GPG_ERR_NO_ERROR){
283
fprintf(stderr, "bad gpgme_data_new_from_mem: %s: %s\n",
284
gpgme_strsource(rc), gpgme_strerror(rc));
389
fprintf_plus(stderr, "bad gpgme_data_new_from_mem: %s: %s\n",
390
gpgme_strsource(rc), gpgme_strerror(rc));
288
394
/* Create new empty GPGME data buffer for the plaintext */
289
395
rc = gpgme_data_new(&dh_plain);
290
396
if(rc != GPG_ERR_NO_ERROR){
291
fprintf(stderr, "bad gpgme_data_new: %s: %s\n",
292
gpgme_strsource(rc), gpgme_strerror(rc));
397
fprintf_plus(stderr, "Mandos plugin mandos-client: "
398
"bad gpgme_data_new: %s: %s\n",
399
gpgme_strsource(rc), gpgme_strerror(rc));
293
400
gpgme_data_release(dh_crypto);
297
404
/* Decrypt data from the cryptotext data buffer to the plaintext
299
rc = gpgme_op_decrypt(mc.ctx, dh_crypto, dh_plain);
406
rc = gpgme_op_decrypt(mc->ctx, dh_crypto, dh_plain);
300
407
if(rc != GPG_ERR_NO_ERROR){
301
fprintf(stderr, "bad gpgme_op_decrypt: %s: %s\n",
302
gpgme_strsource(rc), gpgme_strerror(rc));
408
fprintf_plus(stderr, "bad gpgme_op_decrypt: %s: %s\n",
409
gpgme_strsource(rc), gpgme_strerror(rc));
303
410
plaintext_length = -1;
305
412
gpgme_decrypt_result_t result;
306
result = gpgme_op_decrypt_result(mc.ctx);
413
result = gpgme_op_decrypt_result(mc->ctx);
307
414
if(result == NULL){
308
fprintf(stderr, "gpgme_op_decrypt_result failed\n");
415
fprintf_plus(stderr, "gpgme_op_decrypt_result failed\n");
310
fprintf(stderr, "Unsupported algorithm: %s\n",
311
result->unsupported_algorithm);
312
fprintf(stderr, "Wrong key usage: %u\n",
313
result->wrong_key_usage);
417
fprintf_plus(stderr, "Unsupported algorithm: %s\n",
418
result->unsupported_algorithm);
419
fprintf_plus(stderr, "Wrong key usage: %u\n",
420
result->wrong_key_usage);
314
421
if(result->file_name != NULL){
315
fprintf(stderr, "File name: %s\n", result->file_name);
422
fprintf_plus(stderr, "File name: %s\n", result->file_name);
317
424
gpgme_recipient_t recipient;
318
425
recipient = result->recipients;
319
426
while(recipient != NULL){
320
fprintf(stderr, "Public key algorithm: %s\n",
321
gpgme_pubkey_algo_name(recipient->pubkey_algo));
322
fprintf(stderr, "Key ID: %s\n", recipient->keyid);
323
fprintf(stderr, "Secret key available: %s\n",
324
recipient->status == GPG_ERR_NO_SECKEY
427
fprintf_plus(stderr, "Public key algorithm: %s\n",
428
gpgme_pubkey_algo_name
429
(recipient->pubkey_algo));
430
fprintf_plus(stderr, "Key ID: %s\n", recipient->keyid);
431
fprintf_plus(stderr, "Secret key available: %s\n",
432
recipient->status == GPG_ERR_NO_SECKEY
326
434
recipient = recipient->next;
425
536
/* OpenPGP credentials */
426
gnutls_certificate_allocate_credentials(&mc.cred);
537
ret = gnutls_certificate_allocate_credentials(&mc->cred);
427
538
if(ret != GNUTLS_E_SUCCESS){
428
fprintf(stderr, "GnuTLS memory error: %s\n", /* Spurious warning
432
safer_gnutls_strerror(ret));
539
fprintf_plus(stderr, "GnuTLS memory error: %s\n",
540
safer_gnutls_strerror(ret));
433
541
gnutls_global_deinit();
438
fprintf(stderr, "Attempting to use OpenPGP public key %s and"
439
" secret key %s as GnuTLS credentials\n", pubkeyfilename,
546
fprintf_plus(stderr, "Attempting to use OpenPGP public key %s and"
547
" secret key %s as GnuTLS credentials\n",
443
552
ret = gnutls_certificate_set_openpgp_key_file
444
(mc.cred, pubkeyfilename, seckeyfilename,
553
(mc->cred, pubkeyfilename, seckeyfilename,
445
554
GNUTLS_OPENPGP_FMT_BASE64);
446
555
if(ret != GNUTLS_E_SUCCESS){
448
"Error[%d] while reading the OpenPGP key pair ('%s',"
449
" '%s')\n", ret, pubkeyfilename, seckeyfilename);
450
fprintf(stderr, "The GnuTLS error is: %s\n",
451
safer_gnutls_strerror(ret));
557
"Error[%d] while reading the OpenPGP key pair ('%s',"
558
" '%s')\n", ret, pubkeyfilename, seckeyfilename);
559
fprintf_plus(stderr, "The GnuTLS error is: %s\n",
560
safer_gnutls_strerror(ret));
455
564
/* GnuTLS server initialization */
456
ret = gnutls_dh_params_init(&mc.dh_params);
565
ret = gnutls_dh_params_init(&mc->dh_params);
457
566
if(ret != GNUTLS_E_SUCCESS){
458
fprintf(stderr, "Error in GnuTLS DH parameter initialization:"
459
" %s\n", safer_gnutls_strerror(ret));
567
fprintf_plus(stderr, "Error in GnuTLS DH parameter"
568
" initialization: %s\n",
569
safer_gnutls_strerror(ret));
462
ret = gnutls_dh_params_generate2(mc.dh_params, mc.dh_bits);
572
ret = gnutls_dh_params_generate2(mc->dh_params, mc->dh_bits);
463
573
if(ret != GNUTLS_E_SUCCESS){
464
fprintf(stderr, "Error in GnuTLS prime generation: %s\n",
465
safer_gnutls_strerror(ret));
574
fprintf_plus(stderr, "Error in GnuTLS prime generation: %s\n",
575
safer_gnutls_strerror(ret));
469
gnutls_certificate_set_dh_params(mc.cred, mc.dh_params);
579
gnutls_certificate_set_dh_params(mc->cred, mc->dh_params);
475
gnutls_certificate_free_credentials(mc.cred);
585
gnutls_certificate_free_credentials(mc->cred);
476
586
gnutls_global_deinit();
477
gnutls_dh_params_deinit(mc.dh_params);
587
gnutls_dh_params_deinit(mc->dh_params);
481
static int init_gnutls_session(gnutls_session_t *session){
591
__attribute__((nonnull, warn_unused_result))
592
static int init_gnutls_session(gnutls_session_t *session,
483
595
/* GnuTLS session creation */
1019
1186
signal_received = sig;
1020
1187
int old_errno = errno;
1021
if(mc.simple_poll != NULL){
1022
avahi_simple_poll_quit(mc.simple_poll);
1188
/* set main loop to exit */
1189
if(simple_poll != NULL){
1190
avahi_simple_poll_quit(simple_poll);
1024
1192
errno = old_errno;
1195
__attribute__((nonnull, warn_unused_result))
1196
bool get_flags(const char *ifname, struct ifreq *ifr){
1200
int s = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1203
perror_plus("socket");
1207
strcpy(ifr->ifr_name, ifname);
1208
ret = ioctl(s, SIOCGIFFLAGS, ifr);
1212
perror_plus("ioctl SIOCGIFFLAGS");
1220
__attribute__((nonnull, warn_unused_result))
1221
bool good_flags(const char *ifname, const struct ifreq *ifr){
1223
/* Reject the loopback device */
1224
if(ifr->ifr_flags & IFF_LOOPBACK){
1226
fprintf_plus(stderr, "Rejecting loopback interface \"%s\"\n",
1231
/* Accept point-to-point devices only if connect_to is specified */
1232
if(connect_to != NULL and (ifr->ifr_flags & IFF_POINTOPOINT)){
1234
fprintf_plus(stderr, "Accepting point-to-point interface"
1235
" \"%s\"\n", ifname);
1239
/* Otherwise, reject non-broadcast-capable devices */
1240
if(not (ifr->ifr_flags & IFF_BROADCAST)){
1242
fprintf_plus(stderr, "Rejecting non-broadcast interface"
1243
" \"%s\"\n", ifname);
1247
/* Reject non-ARP interfaces (including dummy interfaces) */
1248
if(ifr->ifr_flags & IFF_NOARP){
1250
fprintf_plus(stderr, "Rejecting non-ARP interface \"%s\"\n",
1256
/* Accept this device */
1258
fprintf_plus(stderr, "Interface \"%s\" is good\n", ifname);
1028
1264
* This function determines if a directory entry in /sys/class/net
1029
1265
* corresponds to an acceptable network device.
1030
1266
* (This function is passed to scandir(3) as a filter function.)
1268
__attribute__((nonnull, warn_unused_result))
1032
1269
int good_interface(const struct dirent *if_entry){
1034
char *flagname = NULL;
1035
int ret = asprintf(&flagname, "%s/%s/flags", sys_class_net,
1041
1270
if(if_entry->d_name[0] == '.'){
1044
int flags_fd = (int)TEMP_FAILURE_RETRY(open(flagname, O_RDONLY));
1049
typedef short ifreq_flags; /* ifreq.ifr_flags in netdevice(7) */
1050
/* read line from flags_fd */
1051
ssize_t to_read = (sizeof(ifreq_flags)*2)+3; /* "0x1003\n" */
1052
char *flagstring = malloc((size_t)to_read+1); /* +1 for final \0 */
1053
flagstring[(size_t)to_read] = '\0';
1054
if(flagstring == NULL){
1060
ssret = (ssize_t)TEMP_FAILURE_RETRY(read(flags_fd, flagstring,
1275
if(not get_flags(if_entry->d_name, &ifr)){
1277
fprintf_plus(stderr, "Failed to get flags for interface "
1278
"\"%s\"\n", if_entry->d_name);
1283
if(not good_flags(if_entry->d_name, &ifr)){
1290
* This function determines if a network interface is up.
1292
__attribute__((nonnull, warn_unused_result))
1293
bool interface_is_up(const char *interface){
1295
if(not get_flags(interface, &ifr)){
1297
fprintf_plus(stderr, "Failed to get flags for interface "
1298
"\"%s\"\n", interface);
1303
return (bool)(ifr.ifr_flags & IFF_UP);
1307
* This function determines if a network interface is running
1309
__attribute__((nonnull, warn_unused_result))
1310
bool interface_is_running(const char *interface){
1312
if(not get_flags(interface, &ifr)){
1314
fprintf_plus(stderr, "Failed to get flags for interface "
1315
"\"%s\"\n", interface);
1320
return (bool)(ifr.ifr_flags & IFF_RUNNING);
1323
__attribute__((nonnull, pure, warn_unused_result))
1324
int notdotentries(const struct dirent *direntry){
1325
/* Skip "." and ".." */
1326
if(direntry->d_name[0] == '.'
1327
and (direntry->d_name[1] == '\0'
1328
or (direntry->d_name[1] == '.'
1329
and direntry->d_name[2] == '\0'))){
1335
/* Is this directory entry a runnable program? */
1336
__attribute__((nonnull, warn_unused_result))
1337
int runnable_hook(const struct dirent *direntry){
1342
if((direntry->d_name)[0] == '\0'){
1347
sret = strspn(direntry->d_name, "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
1348
"abcdefghijklmnopqrstuvwxyz"
1351
if((direntry->d_name)[sret] != '\0'){
1352
/* Contains non-allowed characters */
1354
fprintf_plus(stderr, "Ignoring hook \"%s\" with bad name\n",
1360
ret = fstatat(hookdir_fd, direntry->d_name, &st, 0);
1363
perror_plus("Could not stat hook");
1367
if(not (S_ISREG(st.st_mode))){
1368
/* Not a regular file */
1370
fprintf_plus(stderr, "Ignoring hook \"%s\" - not a file\n",
1375
if(not (st.st_mode & (S_IXUSR | S_IXGRP | S_IXOTH))){
1376
/* Not executable */
1378
fprintf_plus(stderr, "Ignoring hook \"%s\" - not executable\n",
1384
fprintf_plus(stderr, "Hook \"%s\" is acceptable\n",
1390
__attribute__((nonnull, warn_unused_result))
1391
int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,
1392
mandos_context *mc){
1394
struct timespec now;
1395
struct timespec waited_time;
1396
intmax_t block_time;
1399
if(mc->current_server == NULL){
1401
fprintf_plus(stderr, "Wait until first server is found."
1404
ret = avahi_simple_poll_iterate(s, -1);
1407
fprintf_plus(stderr, "Check current_server if we should run"
1410
/* the current time */
1411
ret = clock_gettime(CLOCK_MONOTONIC, &now);
1413
perror_plus("clock_gettime");
1416
/* Calculating in ms how long time between now and server
1417
who we visted longest time ago. Now - last seen. */
1418
waited_time.tv_sec = (now.tv_sec
1419
- mc->current_server->last_seen.tv_sec);
1420
waited_time.tv_nsec = (now.tv_nsec
1421
- mc->current_server->last_seen.tv_nsec);
1422
/* total time is 10s/10,000ms.
1423
Converting to s from ms by dividing by 1,000,
1424
and ns to ms by dividing by 1,000,000. */
1425
block_time = ((retry_interval
1426
- ((intmax_t)waited_time.tv_sec * 1000))
1427
- ((intmax_t)waited_time.tv_nsec / 1000000));
1430
fprintf_plus(stderr, "Blocking for %" PRIdMAX " ms\n",
1434
if(block_time <= 0){
1435
ret = start_mandos_communication(mc->current_server->ip,
1436
mc->current_server->port,
1437
mc->current_server->if_index,
1438
mc->current_server->af, mc);
1440
avahi_simple_poll_quit(s);
1443
ret = clock_gettime(CLOCK_MONOTONIC,
1444
&mc->current_server->last_seen);
1446
perror_plus("clock_gettime");
1449
mc->current_server = mc->current_server->next;
1450
block_time = 0; /* Call avahi to find new Mandos
1451
servers, but don't block */
1454
ret = avahi_simple_poll_iterate(s, (int)block_time);
1457
if(ret > 0 or errno != EINTR){
1458
return (ret != 1) ? ret : 0;
1464
/* Set effective uid to 0, return errno */
1465
__attribute__((warn_unused_result))
1466
error_t raise_privileges(void){
1467
error_t old_errno = errno;
1468
error_t ret_errno = 0;
1469
if(seteuid(0) == -1){
1476
/* Set effective and real user ID to 0. Return errno. */
1477
__attribute__((warn_unused_result))
1478
error_t raise_privileges_permanently(void){
1479
error_t old_errno = errno;
1480
error_t ret_errno = raise_privileges();
1485
if(setuid(0) == -1){
1492
/* Set effective user ID to unprivileged saved user ID */
1493
__attribute__((warn_unused_result))
1494
error_t lower_privileges(void){
1495
error_t old_errno = errno;
1496
error_t ret_errno = 0;
1497
if(seteuid(uid) == -1){
1504
/* Lower privileges permanently */
1505
__attribute__((warn_unused_result))
1506
error_t lower_privileges_permanently(void){
1507
error_t old_errno = errno;
1508
error_t ret_errno = 0;
1509
if(setuid(uid) == -1){
1516
__attribute__((nonnull))
1517
void run_network_hooks(const char *mode, const char *interface,
1519
struct dirent **direntries = NULL;
1520
if(hookdir_fd == -1){
1521
hookdir_fd = open(hookdir, O_RDONLY);
1522
if(hookdir_fd == -1){
1523
if(errno == ENOENT){
1525
fprintf_plus(stderr, "Network hook directory \"%s\" not"
1526
" found\n", hookdir);
1529
perror_plus("open");
1535
#if __GLIBC_PREREQ(2, 15)
1536
int numhooks = scandirat(hookdir_fd, ".", &direntries,
1537
runnable_hook, alphasort);
1538
#else /* not __GLIBC_PREREQ(2, 15) */
1539
int numhooks = scandir(hookdir, &direntries, runnable_hook,
1541
#endif /* not __GLIBC_PREREQ(2, 15) */
1542
#else /* not __GLIBC__ */
1543
int numhooks = scandir(hookdir, &direntries, runnable_hook,
1545
#endif /* not __GLIBC__ */
1547
perror_plus("scandir");
1550
struct dirent *direntry;
1552
int devnull = open("/dev/null", O_RDONLY);
1553
for(int i = 0; i < numhooks; i++){
1554
direntry = direntries[i];
1556
fprintf_plus(stderr, "Running network hook \"%s\"\n",
1559
pid_t hook_pid = fork();
1562
/* Raise privileges */
1563
errno = raise_privileges_permanently();
1565
perror_plus("Failed to raise privileges");
1572
perror_plus("setgid");
1575
/* Reset supplementary groups */
1577
ret = setgroups(0, NULL);
1579
perror_plus("setgroups");
1582
ret = dup2(devnull, STDIN_FILENO);
1584
perror_plus("dup2(devnull, STDIN_FILENO)");
1587
ret = close(devnull);
1589
perror_plus("close");
1592
ret = dup2(STDERR_FILENO, STDOUT_FILENO);
1594
perror_plus("dup2(STDERR_FILENO, STDOUT_FILENO)");
1597
ret = setenv("MANDOSNETHOOKDIR", hookdir, 1);
1599
perror_plus("setenv");
1602
ret = setenv("DEVICE", interface, 1);
1604
perror_plus("setenv");
1607
ret = setenv("VERBOSITY", debug ? "1" : "0", 1);
1609
perror_plus("setenv");
1612
ret = setenv("MODE", mode, 1);
1614
perror_plus("setenv");
1618
ret = asprintf(&delaystring, "%f", (double)delay);
1620
perror_plus("asprintf");
1623
ret = setenv("DELAY", delaystring, 1);
1626
perror_plus("setenv");
1630
if(connect_to != NULL){
1631
ret = setenv("CONNECT", connect_to, 1);
1633
perror_plus("setenv");
1637
int hook_fd = openat(hookdir_fd, direntry->d_name, O_RDONLY);
1639
perror_plus("openat");
1640
_exit(EXIT_FAILURE);
1642
if((int)TEMP_FAILURE_RETRY(close(hookdir_fd)) == -1){
1643
perror_plus("close");
1644
_exit(EXIT_FAILURE);
1646
if(fexecve(hook_fd, (char *const []){ direntry->d_name, NULL },
1648
perror_plus("fexecve");
1649
_exit(EXIT_FAILURE);
1653
if(TEMP_FAILURE_RETRY(waitpid(hook_pid, &status, 0)) == -1){
1654
perror_plus("waitpid");
1657
if(WIFEXITED(status)){
1658
if(WEXITSTATUS(status) != 0){
1659
fprintf_plus(stderr, "Warning: network hook \"%s\" exited"
1660
" with status %d\n", direntry->d_name,
1661
WEXITSTATUS(status));
1664
} else if(WIFSIGNALED(status)){
1665
fprintf_plus(stderr, "Warning: network hook \"%s\" died by"
1666
" signal %d\n", direntry->d_name,
1670
fprintf_plus(stderr, "Warning: network hook \"%s\""
1671
" crashed\n", direntry->d_name);
1676
fprintf_plus(stderr, "Network hook \"%s\" ran successfully\n",
1681
if((int)TEMP_FAILURE_RETRY(close(hookdir_fd)) == -1){
1682
perror_plus("close");
1689
__attribute__((nonnull, warn_unused_result))
1690
error_t bring_up_interface(const char *const interface,
1692
error_t old_errno = errno;
1694
struct ifreq network;
1695
unsigned int if_index = if_nametoindex(interface);
1697
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
1707
if(not interface_is_up(interface)){
1708
error_t ret_errno = 0, ioctl_errno = 0;
1709
if(not get_flags(interface, &network)){
1711
fprintf_plus(stderr, "Failed to get flags for interface "
1712
"\"%s\"\n", interface);
1716
network.ifr_flags |= IFF_UP; /* set flag */
1718
int sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1721
perror_plus("socket");
1727
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1729
perror_plus("close");
1736
fprintf_plus(stderr, "Bringing up interface \"%s\"\n",
1740
/* Raise privileges */
1741
ret_errno = raise_privileges();
1744
perror_plus("Failed to raise privileges");
1749
bool restore_loglevel = false;
1751
/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO
1752
messages about the network interface to mess up the prompt */
1753
ret_linux = klogctl(8, NULL, 5);
1754
if(ret_linux == -1){
1755
perror_plus("klogctl");
1757
restore_loglevel = true;
1760
#endif /* __linux__ */
1761
int ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
1762
ioctl_errno = errno;
1764
if(restore_loglevel){
1765
ret_linux = klogctl(7, NULL, 0);
1766
if(ret_linux == -1){
1767
perror_plus("klogctl");
1770
#endif /* __linux__ */
1772
/* If raise_privileges() succeeded above */
1774
/* Lower privileges */
1775
ret_errno = lower_privileges();
1778
perror_plus("Failed to lower privileges");
1782
/* Close the socket */
1783
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1785
perror_plus("close");
1788
if(ret_setflags == -1){
1789
errno = ioctl_errno;
1790
perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");
1795
fprintf_plus(stderr, "Interface \"%s\" is already up; good\n",
1799
/* Sleep checking until interface is running.
1800
Check every 0.25s, up to total time of delay */
1801
for(int i=0; i < delay * 4; i++){
1802
if(interface_is_running(interface)){
1077
tmpmax = strtoimax(flagstring, &tmp, 0);
1078
if(errno != 0 or tmp == flagstring or (*tmp != '\0'
1079
and not (isspace(*tmp)))
1080
or tmpmax != (ifreq_flags)tmpmax){
1082
fprintf(stderr, "Invalid flags \"%s\" for interface \"%s\"\n",
1083
flagstring, if_entry->d_name);
1089
ifreq_flags flags = (ifreq_flags)tmpmax;
1090
/* Reject the loopback device */
1091
if(flags & IFF_LOOPBACK){
1093
fprintf(stderr, "Rejecting loopback interface \"%s\"\n",
1098
/* Accept point-to-point devices only if connect_to is specified */
1099
if(connect_to != NULL and (flags & IFF_POINTOPOINT)){
1101
fprintf(stderr, "Accepting point-to-point interface \"%s\"\n",
1106
/* Otherwise, reject non-broadcast-capable devices */
1107
if(not (flags & IFF_BROADCAST)){
1109
fprintf(stderr, "Rejecting non-broadcast interface \"%s\"\n",
1114
/* Accept this device */
1116
fprintf(stderr, "Interface \"%s\" is acceptable\n",
1805
struct timespec sleeptime = { .tv_nsec = 250000000 };
1806
ret = nanosleep(&sleeptime, NULL);
1807
if(ret == -1 and errno != EINTR){
1808
perror_plus("nanosleep");
1816
__attribute__((nonnull, warn_unused_result))
1817
error_t take_down_interface(const char *const interface){
1818
error_t old_errno = errno;
1819
struct ifreq network;
1820
unsigned int if_index = if_nametoindex(interface);
1822
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
1826
if(interface_is_up(interface)){
1827
error_t ret_errno = 0, ioctl_errno = 0;
1828
if(not get_flags(interface, &network) and debug){
1830
fprintf_plus(stderr, "Failed to get flags for interface "
1831
"\"%s\"\n", interface);
1835
network.ifr_flags &= ~(short)IFF_UP; /* clear flag */
1837
int sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1840
perror_plus("socket");
1846
fprintf_plus(stderr, "Taking down interface \"%s\"\n",
1850
/* Raise privileges */
1851
ret_errno = raise_privileges();
1854
perror_plus("Failed to raise privileges");
1857
int ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
1858
ioctl_errno = errno;
1860
/* If raise_privileges() succeeded above */
1862
/* Lower privileges */
1863
ret_errno = lower_privileges();
1866
perror_plus("Failed to lower privileges");
1870
/* Close the socket */
1871
int ret = (int)TEMP_FAILURE_RETRY(close(sd));
1873
perror_plus("close");
1876
if(ret_setflags == -1){
1877
errno = ioctl_errno;
1878
perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");
1883
fprintf_plus(stderr, "Interface \"%s\" is already down; odd\n",
1122
1891
int main(int argc, char *argv[]){
1892
mandos_context mc = { .server = NULL, .dh_bits = 1024,
1893
.priority = "SECURE256:!CTYPE-X.509:"
1894
"+CTYPE-OPENPGP", .current_server = NULL,
1895
.interfaces = NULL, .interfaces_size = 0 };
1123
1896
AvahiSServiceBrowser *sb = NULL;
1126
1899
intmax_t tmpmax;
1128
1901
int exitcode = EXIT_SUCCESS;
1129
const char *interface = "";
1130
struct ifreq network;
1132
bool take_down_interface = false;
1135
char tempdir[] = "/tmp/mandosXXXXXX";
1136
bool tempdir_created = false;
1902
char *interfaces_to_take_down = NULL;
1903
size_t interfaces_to_take_down_size = 0;
1904
char run_tempdir[] = "/run/tmp/mandosXXXXXX";
1905
char old_tempdir[] = "/tmp/mandosXXXXXX";
1906
char *tempdir = NULL;
1137
1907
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
1138
1908
const char *seckey = PATHDIR "/" SECKEY;
1139
1909
const char *pubkey = PATHDIR "/" PUBKEY;
1910
char *interfaces_hooks = NULL;
1141
1912
bool gnutls_initialized = false;
1142
1913
bool gpgme_initialized = false;
1143
1914
float delay = 2.5f;
1915
double retry_interval = 10; /* 10s between trying a server and
1916
retrying the same server again */
1145
1918
struct sigaction old_sigterm_action = { .sa_handler = SIG_DFL };
1146
1919
struct sigaction sigterm_action = { .sa_handler = handle_sigterm };
1357
2224
ret = sigaction(SIGINT, NULL, &old_sigterm_action);
1359
perror("sigaction");
2226
perror_plus("sigaction");
1360
2227
return EX_OSERR;
1362
2229
if(old_sigterm_action.sa_handler != SIG_IGN){
1363
2230
ret = sigaction(SIGINT, &sigterm_action, NULL);
1365
perror("sigaction");
2232
perror_plus("sigaction");
1366
2233
exitcode = EX_OSERR;
1370
2237
ret = sigaction(SIGHUP, NULL, &old_sigterm_action);
1372
perror("sigaction");
2239
perror_plus("sigaction");
1373
2240
return EX_OSERR;
1375
2242
if(old_sigterm_action.sa_handler != SIG_IGN){
1376
2243
ret = sigaction(SIGHUP, &sigterm_action, NULL);
1378
perror("sigaction");
2245
perror_plus("sigaction");
1379
2246
exitcode = EX_OSERR;
1383
2250
ret = sigaction(SIGTERM, NULL, &old_sigterm_action);
1385
perror("sigaction");
2252
perror_plus("sigaction");
1386
2253
return EX_OSERR;
1388
2255
if(old_sigterm_action.sa_handler != SIG_IGN){
1389
2256
ret = sigaction(SIGTERM, &sigterm_action, NULL);
1391
perror("sigaction");
1392
exitcode = EX_OSERR;
1397
/* If the interface is down, bring it up */
1398
if(strcmp(interface, "none") != 0){
1399
if_index = (AvahiIfIndex) if_nametoindex(interface);
1401
fprintf(stderr, "No such interface: \"%s\"\n", interface);
1402
exitcode = EX_UNAVAILABLE;
1410
/* Re-raise priviliges */
1418
/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO
1419
messages about the network interface to mess up the prompt */
1420
ret = klogctl(8, NULL, 5);
1421
bool restore_loglevel = true;
1423
restore_loglevel = false;
1426
#endif /* __linux__ */
1428
sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1431
exitcode = EX_OSERR;
1433
if(restore_loglevel){
1434
ret = klogctl(7, NULL, 0);
1439
#endif /* __linux__ */
1440
/* Lower privileges */
1448
strcpy(network.ifr_name, interface);
1449
ret = ioctl(sd, SIOCGIFFLAGS, &network);
1451
perror("ioctl SIOCGIFFLAGS");
1453
if(restore_loglevel){
1454
ret = klogctl(7, NULL, 0);
1459
#endif /* __linux__ */
1460
exitcode = EX_OSERR;
1461
/* Lower privileges */
1469
if((network.ifr_flags & IFF_UP) == 0){
1470
network.ifr_flags |= IFF_UP;
1471
take_down_interface = true;
1472
ret = ioctl(sd, SIOCSIFFLAGS, &network);
1474
take_down_interface = false;
1475
perror("ioctl SIOCSIFFLAGS +IFF_UP");
1476
exitcode = EX_OSERR;
1478
if(restore_loglevel){
1479
ret = klogctl(7, NULL, 0);
2258
perror_plus("sigaction");
2259
exitcode = EX_OSERR;
2264
/* If no interfaces were specified, make a list */
2265
if(mc.interfaces == NULL){
2266
struct dirent **direntries = NULL;
2267
/* Look for any good interfaces */
2268
ret = scandir(sys_class_net, &direntries, good_interface,
2271
/* Add all found interfaces to interfaces list */
2272
for(int i = 0; i < ret; ++i){
2273
ret_errno = argz_add(&mc.interfaces, &mc.interfaces_size,
2274
direntries[i]->d_name);
2277
perror_plus("argz_add");
2281
fprintf_plus(stderr, "Will use interface \"%s\"\n",
2282
direntries[i]->d_name);
2290
fprintf_plus(stderr, "Could not find a network interface\n");
2291
exitcode = EXIT_FAILURE;
2296
/* Bring up interfaces which are down, and remove any "none"s */
2298
char *interface = NULL;
2299
while((interface = argz_next(mc.interfaces, mc.interfaces_size,
2301
/* If interface name is "none", stop bringing up interfaces.
2302
Also remove all instances of "none" from the list */
2303
if(strcmp(interface, "none") == 0){
2304
argz_delete(&mc.interfaces, &mc.interfaces_size,
2307
while((interface = argz_next(mc.interfaces,
2308
mc.interfaces_size, interface))){
2309
if(strcmp(interface, "none") == 0){
2310
argz_delete(&mc.interfaces, &mc.interfaces_size,
1484
#endif /* __linux__ */
1485
/* Lower privileges */
1494
/* sleep checking until interface is running */
1495
for(int i=0; i < delay * 4; i++){
1496
ret = ioctl(sd, SIOCGIFFLAGS, &network);
1498
perror("ioctl SIOCGIFFLAGS");
1499
} else if(network.ifr_flags & IFF_RUNNING){
1502
struct timespec sleeptime = { .tv_nsec = 250000000 };
1503
ret = nanosleep(&sleeptime, NULL);
1504
if(ret == -1 and errno != EINTR){
1505
perror("nanosleep");
1508
if(not take_down_interface){
1509
/* We won't need the socket anymore */
1510
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1516
if(restore_loglevel){
1517
/* Restores kernel loglevel to default */
1518
ret = klogctl(7, NULL, 0);
1523
#endif /* __linux__ */
1524
/* Lower privileges */
1526
if(take_down_interface){
1527
/* Lower privileges */
1533
/* Lower privileges permanently */
2317
bool interface_was_up = interface_is_up(interface);
2318
errno = bring_up_interface(interface, delay);
2319
if(not interface_was_up){
2321
perror_plus("Failed to bring up interface");
2323
errno = argz_add(&interfaces_to_take_down,
2324
&interfaces_to_take_down_size,
2327
perror_plus("argz_add");
2332
if(debug and (interfaces_to_take_down == NULL)){
2333
fprintf_plus(stderr, "No interfaces were brought up\n");
2337
/* If we only got one interface, explicitly use only that one */
2338
if(argz_count(mc.interfaces, mc.interfaces_size) == 1){
2340
fprintf_plus(stderr, "Using only interface \"%s\"\n",
2343
if_index = (AvahiIfIndex)if_nametoindex(mc.interfaces);
1545
ret = init_gnutls_global(pubkey, seckey);
2350
ret = init_gnutls_global(pubkey, seckey, &mc);
1547
fprintf(stderr, "init_gnutls_global failed\n");
2352
fprintf_plus(stderr, "init_gnutls_global failed\n");
1548
2353
exitcode = EX_UNAVAILABLE;
1719
2550
gpgme_release(mc.ctx);
1722
/* Take down the network interface */
1723
if(take_down_interface){
1724
/* Re-raise priviliges */
1731
ret = ioctl(sd, SIOCGIFFLAGS, &network);
1733
perror("ioctl SIOCGIFFLAGS");
1734
} else if(network.ifr_flags & IFF_UP) {
1735
network.ifr_flags &= ~(short)IFF_UP; /* clear flag */
1736
ret = ioctl(sd, SIOCSIFFLAGS, &network);
1738
perror("ioctl SIOCSIFFLAGS -IFF_UP");
1741
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1745
/* Lower privileges permanently */
1754
/* Removes the temp directory used by GPGME */
1755
if(tempdir_created){
1757
struct dirent *direntry;
1758
d = opendir(tempdir);
1760
if(errno != ENOENT){
1765
direntry = readdir(d);
1766
if(direntry == NULL){
1769
/* Skip "." and ".." */
1770
if(direntry->d_name[0] == '.'
1771
and (direntry->d_name[1] == '\0'
1772
or (direntry->d_name[1] == '.'
1773
and direntry->d_name[2] == '\0'))){
1776
char *fullname = NULL;
1777
ret = asprintf(&fullname, "%s/%s", tempdir,
1783
ret = remove(fullname);
1785
fprintf(stderr, "remove(\"%s\"): %s\n", fullname,
1792
ret = rmdir(tempdir);
1793
if(ret == -1 and errno != ENOENT){
2553
/* Cleans up the circular linked list of Mandos servers the client
2555
if(mc.current_server != NULL){
2556
mc.current_server->prev->next = NULL;
2557
while(mc.current_server != NULL){
2558
server *next = mc.current_server->next;
2560
#pragma GCC diagnostic push
2561
#pragma GCC diagnostic ignored "-Wcast-qual"
2563
free((char *)(mc.current_server->ip));
2565
#pragma GCC diagnostic pop
2567
free(mc.current_server);
2568
mc.current_server = next;
2572
/* Re-raise privileges */
2574
ret_errno = raise_privileges();
2577
perror_plus("Failed to raise privileges");
2580
/* Run network hooks */
2581
run_network_hooks("stop", interfaces_hooks != NULL ?
2582
interfaces_hooks : "", delay);
2584
/* Take down the network interfaces which were brought up */
2586
char *interface = NULL;
2587
while((interface=argz_next(interfaces_to_take_down,
2588
interfaces_to_take_down_size,
2590
ret_errno = take_down_interface(interface);
2593
perror_plus("Failed to take down interface");
2596
if(debug and (interfaces_to_take_down == NULL)){
2597
fprintf_plus(stderr, "No interfaces needed to be taken"
2603
ret_errno = lower_privileges_permanently();
2606
perror_plus("Failed to lower privileges permanently");
2610
free(interfaces_to_take_down);
2611
free(interfaces_hooks);
2613
/* Removes the GPGME temp directory and all files inside */
2614
if(tempdir != NULL){
2615
struct dirent **direntries = NULL;
2616
int tempdir_fd = (int)TEMP_FAILURE_RETRY(open(tempdir, O_RDONLY |
2618
if(tempdir_fd == -1){
2619
perror_plus("open");
2622
#if __GLIBC_PREREQ(2, 15)
2623
int numentries = scandirat(tempdir_fd, ".", &direntries,
2624
notdotentries, alphasort);
2625
#else /* not __GLIBC_PREREQ(2, 15) */
2626
int numentries = scandir(tempdir, &direntries, notdotentries,
2628
#endif /* not __GLIBC_PREREQ(2, 15) */
2629
#else /* not __GLIBC__ */
2630
int numentries = scandir(tempdir, &direntries, notdotentries,
2632
#endif /* not __GLIBC__ */
2633
if(numentries >= 0){
2634
for(int i = 0; i < numentries; i++){
2635
ret = unlinkat(tempdir_fd, direntries[i]->d_name, 0);
2637
fprintf_plus(stderr, "unlinkat(open(\"%s\", O_RDONLY),"
2638
" \"%s\", 0): %s\n", tempdir,
2639
direntries[i]->d_name, strerror(errno));
2643
/* need to clean even if 0 because man page doesn't specify */
2645
if(numentries == -1){
2646
perror_plus("scandir");
2648
ret = rmdir(tempdir);
2649
if(ret == -1 and errno != ENOENT){
2650
perror_plus("rmdir");
2653
TEMP_FAILURE_RETRY(close(tempdir_fd));