120
132
#define PATHDIR "/conf/conf.d/mandos"
121
133
#define SECKEY "seckey.txt"
122
134
#define PUBKEY "pubkey.txt"
135
#define HOOKDIR "/lib/mandos/network-hooks.d"
124
137
bool debug = false;
125
138
static const char mandos_protocol_version[] = "1";
126
139
const char *argp_program_version = "mandos-client " VERSION;
127
const char *argp_program_bug_address = "<mandos@fukt.bsnet.se>";
140
const char *argp_program_bug_address = "<mandos@recompile.se>";
128
141
static const char sys_class_net[] = "/sys/class/net";
129
142
char *connect_to = NULL;
143
const char *hookdir = HOOKDIR;
147
/* Doubly linked list that need to be circularly linked when used */
148
typedef struct server{
151
AvahiIfIndex if_index;
153
struct timespec last_seen;
131
158
/* Used for passing in values through the Avahi callback functions */
133
AvahiSimplePoll *simple_poll;
134
160
AvahiServer *server;
135
161
gnutls_certificate_credentials_t cred;
136
162
unsigned int dh_bits;
137
163
gnutls_dh_params_t dh_params;
138
164
const char *priority;
166
server *current_server;
168
size_t interfaces_size;
140
169
} mandos_context;
142
/* global context so signal handler can reach it*/
143
mandos_context mc = { .simple_poll = NULL, .server = NULL,
144
.dh_bits = 1024, .priority = "SECURE256"
145
":!CTYPE-X.509:+CTYPE-OPENPGP" };
171
/* global so signal handler can reach it*/
172
AvahiSimplePoll *simple_poll;
147
174
sig_atomic_t quit_now = 0;
148
175
int signal_received = 0;
177
/* Function to use when printing errors */
178
void perror_plus(const char *print_text){
180
fprintf(stderr, "Mandos plugin %s: ",
181
program_invocation_short_name);
186
__attribute__((format (gnu_printf, 2, 3), nonnull))
187
int fprintf_plus(FILE *stream, const char *format, ...){
189
va_start (ap, format);
191
TEMP_FAILURE_RETRY(fprintf(stream, "Mandos plugin %s: ",
192
program_invocation_short_name));
193
return (int)TEMP_FAILURE_RETRY(vfprintf(stream, format, ap));
151
197
* Make additional room in "buffer" for at least BUFFER_SIZE more
152
198
* bytes. "buffer_capacity" is how much is currently allocated,
153
199
* "buffer_length" is how much is already used.
201
__attribute__((nonnull, warn_unused_result))
155
202
size_t incbuffer(char **buffer, size_t buffer_length,
156
size_t buffer_capacity){
203
size_t buffer_capacity){
157
204
if(buffer_length + BUFFER_SIZE > buffer_capacity){
158
*buffer = realloc(*buffer, buffer_capacity + BUFFER_SIZE);
205
char *new_buf = realloc(*buffer, buffer_capacity + BUFFER_SIZE);
207
int old_errno = errno;
162
214
buffer_capacity += BUFFER_SIZE;
164
216
return buffer_capacity;
219
/* Add server to set of servers to retry periodically */
220
__attribute__((nonnull, warn_unused_result))
221
bool add_server(const char *ip, in_port_t port, AvahiIfIndex if_index,
222
int af, server **current_server){
224
server *new_server = malloc(sizeof(server));
225
if(new_server == NULL){
226
perror_plus("malloc");
229
*new_server = (server){ .ip = strdup(ip),
231
.if_index = if_index,
233
if(new_server->ip == NULL){
234
perror_plus("strdup");
237
ret = clock_gettime(CLOCK_MONOTONIC, &(new_server->last_seen));
239
perror_plus("clock_gettime");
242
/* Special case of first server */
243
if(*current_server == NULL){
244
new_server->next = new_server;
245
new_server->prev = new_server;
246
*current_server = new_server;
248
/* Place the new server last in the list */
249
new_server->next = *current_server;
250
new_server->prev = (*current_server)->prev;
251
new_server->prev->next = new_server;
252
(*current_server)->prev = new_server;
168
258
* Initialize GPGME.
170
static bool init_gpgme(const char *seckey,
171
const char *pubkey, const char *tempdir){
260
__attribute__((nonnull, warn_unused_result))
261
static bool init_gpgme(const char *seckey, const char *pubkey,
262
const char *tempdir, mandos_context *mc){
172
263
gpgme_error_t rc;
173
264
gpgme_engine_info_t engine_info;
177
267
* Helper function to insert pub and seckey to the engine keyring.
271
365
ssize_t plaintext_length = 0;
274
fprintf(stderr, "Trying to decrypt OpenPGP data\n");
368
fprintf_plus(stderr, "Trying to decrypt OpenPGP data\n");
277
371
/* Create new GPGME data buffer from memory cryptotext */
278
372
rc = gpgme_data_new_from_mem(&dh_crypto, cryptotext, crypto_size,
280
374
if(rc != GPG_ERR_NO_ERROR){
281
fprintf(stderr, "bad gpgme_data_new_from_mem: %s: %s\n",
282
gpgme_strsource(rc), gpgme_strerror(rc));
375
fprintf_plus(stderr, "bad gpgme_data_new_from_mem: %s: %s\n",
376
gpgme_strsource(rc), gpgme_strerror(rc));
286
380
/* Create new empty GPGME data buffer for the plaintext */
287
381
rc = gpgme_data_new(&dh_plain);
288
382
if(rc != GPG_ERR_NO_ERROR){
289
fprintf(stderr, "bad gpgme_data_new: %s: %s\n",
290
gpgme_strsource(rc), gpgme_strerror(rc));
383
fprintf_plus(stderr, "Mandos plugin mandos-client: "
384
"bad gpgme_data_new: %s: %s\n",
385
gpgme_strsource(rc), gpgme_strerror(rc));
291
386
gpgme_data_release(dh_crypto);
295
390
/* Decrypt data from the cryptotext data buffer to the plaintext
297
rc = gpgme_op_decrypt(mc.ctx, dh_crypto, dh_plain);
392
rc = gpgme_op_decrypt(mc->ctx, dh_crypto, dh_plain);
298
393
if(rc != GPG_ERR_NO_ERROR){
299
fprintf(stderr, "bad gpgme_op_decrypt: %s: %s\n",
300
gpgme_strsource(rc), gpgme_strerror(rc));
394
fprintf_plus(stderr, "bad gpgme_op_decrypt: %s: %s\n",
395
gpgme_strsource(rc), gpgme_strerror(rc));
301
396
plaintext_length = -1;
303
398
gpgme_decrypt_result_t result;
304
result = gpgme_op_decrypt_result(mc.ctx);
399
result = gpgme_op_decrypt_result(mc->ctx);
305
400
if(result == NULL){
306
fprintf(stderr, "gpgme_op_decrypt_result failed\n");
401
fprintf_plus(stderr, "gpgme_op_decrypt_result failed\n");
308
fprintf(stderr, "Unsupported algorithm: %s\n",
309
result->unsupported_algorithm);
310
fprintf(stderr, "Wrong key usage: %u\n",
311
result->wrong_key_usage);
403
fprintf_plus(stderr, "Unsupported algorithm: %s\n",
404
result->unsupported_algorithm);
405
fprintf_plus(stderr, "Wrong key usage: %u\n",
406
result->wrong_key_usage);
312
407
if(result->file_name != NULL){
313
fprintf(stderr, "File name: %s\n", result->file_name);
408
fprintf_plus(stderr, "File name: %s\n", result->file_name);
315
410
gpgme_recipient_t recipient;
316
411
recipient = result->recipients;
317
412
while(recipient != NULL){
318
fprintf(stderr, "Public key algorithm: %s\n",
319
gpgme_pubkey_algo_name(recipient->pubkey_algo));
320
fprintf(stderr, "Key ID: %s\n", recipient->keyid);
321
fprintf(stderr, "Secret key available: %s\n",
322
recipient->status == GPG_ERR_NO_SECKEY
413
fprintf_plus(stderr, "Public key algorithm: %s\n",
414
gpgme_pubkey_algo_name
415
(recipient->pubkey_algo));
416
fprintf_plus(stderr, "Key ID: %s\n", recipient->keyid);
417
fprintf_plus(stderr, "Secret key available: %s\n",
418
recipient->status == GPG_ERR_NO_SECKEY
324
420
recipient = recipient->next;
423
522
/* OpenPGP credentials */
424
gnutls_certificate_allocate_credentials(&mc.cred);
523
ret = gnutls_certificate_allocate_credentials(&mc->cred);
425
524
if(ret != GNUTLS_E_SUCCESS){
426
fprintf(stderr, "GnuTLS memory error: %s\n", /* Spurious warning
430
safer_gnutls_strerror(ret));
525
fprintf_plus(stderr, "GnuTLS memory error: %s\n",
526
safer_gnutls_strerror(ret));
431
527
gnutls_global_deinit();
436
fprintf(stderr, "Attempting to use OpenPGP public key %s and"
437
" secret key %s as GnuTLS credentials\n", pubkeyfilename,
532
fprintf_plus(stderr, "Attempting to use OpenPGP public key %s and"
533
" secret key %s as GnuTLS credentials\n",
441
538
ret = gnutls_certificate_set_openpgp_key_file
442
(mc.cred, pubkeyfilename, seckeyfilename,
539
(mc->cred, pubkeyfilename, seckeyfilename,
443
540
GNUTLS_OPENPGP_FMT_BASE64);
444
541
if(ret != GNUTLS_E_SUCCESS){
446
"Error[%d] while reading the OpenPGP key pair ('%s',"
447
" '%s')\n", ret, pubkeyfilename, seckeyfilename);
448
fprintf(stderr, "The GnuTLS error is: %s\n",
449
safer_gnutls_strerror(ret));
543
"Error[%d] while reading the OpenPGP key pair ('%s',"
544
" '%s')\n", ret, pubkeyfilename, seckeyfilename);
545
fprintf_plus(stderr, "The GnuTLS error is: %s\n",
546
safer_gnutls_strerror(ret));
453
550
/* GnuTLS server initialization */
454
ret = gnutls_dh_params_init(&mc.dh_params);
551
ret = gnutls_dh_params_init(&mc->dh_params);
455
552
if(ret != GNUTLS_E_SUCCESS){
456
fprintf(stderr, "Error in GnuTLS DH parameter initialization:"
457
" %s\n", safer_gnutls_strerror(ret));
553
fprintf_plus(stderr, "Error in GnuTLS DH parameter"
554
" initialization: %s\n",
555
safer_gnutls_strerror(ret));
460
ret = gnutls_dh_params_generate2(mc.dh_params, mc.dh_bits);
558
ret = gnutls_dh_params_generate2(mc->dh_params, mc->dh_bits);
461
559
if(ret != GNUTLS_E_SUCCESS){
462
fprintf(stderr, "Error in GnuTLS prime generation: %s\n",
463
safer_gnutls_strerror(ret));
560
fprintf_plus(stderr, "Error in GnuTLS prime generation: %s\n",
561
safer_gnutls_strerror(ret));
467
gnutls_certificate_set_dh_params(mc.cred, mc.dh_params);
565
gnutls_certificate_set_dh_params(mc->cred, mc->dh_params);
473
gnutls_certificate_free_credentials(mc.cred);
571
gnutls_certificate_free_credentials(mc->cred);
474
572
gnutls_global_deinit();
475
gnutls_dh_params_deinit(mc.dh_params);
573
gnutls_dh_params_deinit(mc->dh_params);
479
static int init_gnutls_session(gnutls_session_t *session){
577
__attribute__((nonnull, warn_unused_result))
578
static int init_gnutls_session(gnutls_session_t *session,
481
581
/* GnuTLS session creation */
569
fprintf(stderr, "Bad address family: %d\n", af);
671
fprintf_plus(stderr, "Bad address family: %d\n", af);
573
ret = init_gnutls_session(&session);
676
/* If the interface is specified and we have a list of interfaces */
677
if(if_index != AVAHI_IF_UNSPEC and mc->interfaces != NULL){
678
/* Check if the interface is one of the interfaces we are using */
681
char *interface = NULL;
682
while((interface=argz_next(mc->interfaces, mc->interfaces_size,
684
if(if_nametoindex(interface) == (unsigned int)if_index){
691
/* This interface does not match any in the list, so we don't
692
connect to the server */
694
char interface[IF_NAMESIZE];
695
if(if_indextoname((unsigned int)if_index, interface) == NULL){
696
perror_plus("if_indextoname");
698
fprintf_plus(stderr, "Skipping server on non-used interface"
700
if_indextoname((unsigned int)if_index,
708
ret = init_gnutls_session(&session, mc);
579
fprintf(stderr, "Setting up a TCP connection to %s, port %" PRIu16
714
fprintf_plus(stderr, "Setting up a TCP connection to %s, port %"
715
PRIuMAX "\n", ip, (uintmax_t)port);
583
718
tcp_sd = socket(pf, SOCK_STREAM, 0);
721
perror_plus("socket");
593
731
memset(&to, 0, sizeof(to));
594
732
if(af == AF_INET6){
595
to.in6.sin6_family = (sa_family_t)af;
596
ret = inet_pton(af, ip, &to.in6.sin6_addr);
733
((struct sockaddr_in6 *)&to)->sin6_family = (sa_family_t)af;
734
ret = inet_pton(af, ip, &((struct sockaddr_in6 *)&to)->sin6_addr);
597
735
} else { /* IPv4 */
598
to.in.sin_family = (sa_family_t)af;
599
ret = inet_pton(af, ip, &to.in.sin_addr);
736
((struct sockaddr_in *)&to)->sin_family = (sa_family_t)af;
737
ret = inet_pton(af, ip, &((struct sockaddr_in *)&to)->sin_addr);
741
perror_plus("inet_pton");
606
fprintf(stderr, "Bad address: %s\n", ip);
747
fprintf_plus(stderr, "Bad address: %s\n", ip);
609
751
if(af == AF_INET6){
610
to.in6.sin6_port = htons(port); /* Spurious warnings from
612
-Wunreachable-code */
614
if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */
615
(&to.in6.sin6_addr)){ /* -Wstrict-aliasing=2 or lower and
752
((struct sockaddr_in6 *)&to)->sin6_port = htons(port);
753
if(IN6_IS_ADDR_LINKLOCAL
754
(&((struct sockaddr_in6 *)&to)->sin6_addr)){
617
755
if(if_index == AVAHI_IF_UNSPEC){
618
fprintf(stderr, "An IPv6 link-local address is incomplete"
619
" without a network interface\n");
756
fprintf_plus(stderr, "An IPv6 link-local address is"
757
" incomplete without a network interface\n");
622
761
/* Set the network interface number as scope */
623
to.in6.sin6_scope_id = (uint32_t)if_index;
762
((struct sockaddr_in6 *)&to)->sin6_scope_id = (uint32_t)if_index;
626
to.in.sin_port = htons(port); /* Spurious warnings from
628
-Wunreachable-code */
765
((struct sockaddr_in *)&to)->sin_port = htons(port);
971
1172
signal_received = sig;
972
1173
int old_errno = errno;
973
if(mc.simple_poll != NULL){
974
avahi_simple_poll_quit(mc.simple_poll);
1174
/* set main loop to exit */
1175
if(simple_poll != NULL){
1176
avahi_simple_poll_quit(simple_poll);
976
1178
errno = old_errno;
1181
__attribute__((nonnull, warn_unused_result))
1182
bool get_flags(const char *ifname, struct ifreq *ifr){
1186
int s = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1189
perror_plus("socket");
1193
strcpy(ifr->ifr_name, ifname);
1194
ret = ioctl(s, SIOCGIFFLAGS, ifr);
1198
perror_plus("ioctl SIOCGIFFLAGS");
1206
__attribute__((nonnull, warn_unused_result))
1207
bool good_flags(const char *ifname, const struct ifreq *ifr){
1209
/* Reject the loopback device */
1210
if(ifr->ifr_flags & IFF_LOOPBACK){
1212
fprintf_plus(stderr, "Rejecting loopback interface \"%s\"\n",
1217
/* Accept point-to-point devices only if connect_to is specified */
1218
if(connect_to != NULL and (ifr->ifr_flags & IFF_POINTOPOINT)){
1220
fprintf_plus(stderr, "Accepting point-to-point interface"
1221
" \"%s\"\n", ifname);
1225
/* Otherwise, reject non-broadcast-capable devices */
1226
if(not (ifr->ifr_flags & IFF_BROADCAST)){
1228
fprintf_plus(stderr, "Rejecting non-broadcast interface"
1229
" \"%s\"\n", ifname);
1233
/* Reject non-ARP interfaces (including dummy interfaces) */
1234
if(ifr->ifr_flags & IFF_NOARP){
1236
fprintf_plus(stderr, "Rejecting non-ARP interface \"%s\"\n",
1242
/* Accept this device */
1244
fprintf_plus(stderr, "Interface \"%s\" is good\n", ifname);
980
1250
* This function determines if a directory entry in /sys/class/net
981
1251
* corresponds to an acceptable network device.
982
1252
* (This function is passed to scandir(3) as a filter function.)
1254
__attribute__((nonnull, warn_unused_result))
984
1255
int good_interface(const struct dirent *if_entry){
986
char *flagname = NULL;
987
int ret = asprintf(&flagname, "%s/%s/flags", sys_class_net,
993
1256
if(if_entry->d_name[0] == '.'){
996
int flags_fd = (int)TEMP_FAILURE_RETRY(open(flagname, O_RDONLY));
1001
typedef short ifreq_flags; /* ifreq.ifr_flags in netdevice(7) */
1002
/* read line from flags_fd */
1003
ssize_t to_read = (sizeof(ifreq_flags)*2)+3; /* "0x1003\n" */
1004
char *flagstring = malloc((size_t)to_read);
1005
if(flagstring == NULL){
1011
ssret = (ssize_t)TEMP_FAILURE_RETRY(read(flags_fd, flagstring,
1261
if(not get_flags(if_entry->d_name, &ifr)){
1263
fprintf_plus(stderr, "Failed to get flags for interface "
1264
"\"%s\"\n", if_entry->d_name);
1269
if(not good_flags(if_entry->d_name, &ifr)){
1276
* This function determines if a network interface is up.
1278
__attribute__((nonnull, warn_unused_result))
1279
bool interface_is_up(const char *interface){
1281
if(not get_flags(interface, &ifr)){
1283
fprintf_plus(stderr, "Failed to get flags for interface "
1284
"\"%s\"\n", interface);
1289
return (bool)(ifr.ifr_flags & IFF_UP);
1293
* This function determines if a network interface is running
1295
__attribute__((nonnull, warn_unused_result))
1296
bool interface_is_running(const char *interface){
1298
if(not get_flags(interface, &ifr)){
1300
fprintf_plus(stderr, "Failed to get flags for interface "
1301
"\"%s\"\n", interface);
1306
return (bool)(ifr.ifr_flags & IFF_RUNNING);
1309
__attribute__((nonnull, pure, warn_unused_result))
1310
int notdotentries(const struct dirent *direntry){
1311
/* Skip "." and ".." */
1312
if(direntry->d_name[0] == '.'
1313
and (direntry->d_name[1] == '\0'
1314
or (direntry->d_name[1] == '.'
1315
and direntry->d_name[2] == '\0'))){
1321
/* Is this directory entry a runnable program? */
1322
__attribute__((nonnull, warn_unused_result))
1323
int runnable_hook(const struct dirent *direntry){
1328
if((direntry->d_name)[0] == '\0'){
1333
sret = strspn(direntry->d_name, "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
1334
"abcdefghijklmnopqrstuvwxyz"
1337
if((direntry->d_name)[sret] != '\0'){
1338
/* Contains non-allowed characters */
1340
fprintf_plus(stderr, "Ignoring hook \"%s\" with bad name\n",
1346
char *fullname = NULL;
1347
ret = asprintf(&fullname, "%s/%s", hookdir, direntry->d_name);
1349
perror_plus("asprintf");
1353
ret = stat(fullname, &st);
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){
1464
perror_plus("seteuid");
1470
/* Set effective and real user ID to 0. Return errno. */
1471
__attribute__((warn_unused_result))
1472
error_t raise_privileges_permanently(void){
1473
error_t old_errno = errno;
1474
error_t ret_errno = raise_privileges();
1479
if(setuid(0) == -1){
1481
perror_plus("seteuid");
1487
/* Set effective user ID to unprivileged saved user ID */
1488
__attribute__((warn_unused_result))
1489
error_t lower_privileges(void){
1490
error_t old_errno = errno;
1491
error_t ret_errno = 0;
1492
if(seteuid(uid) == -1){
1494
perror_plus("seteuid");
1500
/* Lower privileges permanently */
1501
__attribute__((warn_unused_result))
1502
error_t lower_privileges_permanently(void){
1503
error_t old_errno = errno;
1504
error_t ret_errno = 0;
1505
if(setuid(uid) == -1){
1507
perror_plus("setuid");
1513
__attribute__((nonnull))
1514
void run_network_hooks(const char *mode, const char *interface,
1516
struct dirent **direntries;
1517
int numhooks = scandir(hookdir, &direntries, runnable_hook,
1520
if(errno == ENOENT){
1522
fprintf_plus(stderr, "Network hook directory \"%s\" not"
1523
" found\n", hookdir);
1526
perror_plus("scandir");
1529
struct dirent *direntry;
1531
int devnull = open("/dev/null", O_RDONLY);
1532
for(int i = 0; i < numhooks; i++){
1533
direntry = direntries[i];
1534
char *fullname = NULL;
1535
ret = asprintf(&fullname, "%s/%s", hookdir, direntry->d_name);
1537
perror_plus("asprintf");
1541
fprintf_plus(stderr, "Running network hook \"%s\"\n",
1544
pid_t hook_pid = fork();
1547
/* Raise privileges */
1548
if(raise_privileges_permanently() != 0){
1549
perror_plus("Failed to raise privileges");
1556
perror_plus("setgid");
1559
/* Reset supplementary groups */
1561
ret = setgroups(0, NULL);
1563
perror_plus("setgroups");
1566
ret = dup2(devnull, STDIN_FILENO);
1568
perror_plus("dup2(devnull, STDIN_FILENO)");
1571
ret = close(devnull);
1573
perror_plus("close");
1576
ret = dup2(STDERR_FILENO, STDOUT_FILENO);
1578
perror_plus("dup2(STDERR_FILENO, STDOUT_FILENO)");
1581
ret = setenv("MANDOSNETHOOKDIR", hookdir, 1);
1583
perror_plus("setenv");
1586
ret = setenv("DEVICE", interface, 1);
1588
perror_plus("setenv");
1591
ret = setenv("VERBOSITY", debug ? "1" : "0", 1);
1593
perror_plus("setenv");
1596
ret = setenv("MODE", mode, 1);
1598
perror_plus("setenv");
1602
ret = asprintf(&delaystring, "%f", (double)delay);
1604
perror_plus("asprintf");
1607
ret = setenv("DELAY", delaystring, 1);
1610
perror_plus("setenv");
1614
if(connect_to != NULL){
1615
ret = setenv("CONNECT", connect_to, 1);
1617
perror_plus("setenv");
1621
if(execl(fullname, direntry->d_name, mode, NULL) == -1){
1622
perror_plus("execl");
1623
_exit(EXIT_FAILURE);
1627
if(TEMP_FAILURE_RETRY(waitpid(hook_pid, &status, 0)) == -1){
1628
perror_plus("waitpid");
1632
if(WIFEXITED(status)){
1633
if(WEXITSTATUS(status) != 0){
1634
fprintf_plus(stderr, "Warning: network hook \"%s\" exited"
1635
" with status %d\n", direntry->d_name,
1636
WEXITSTATUS(status));
1640
} else if(WIFSIGNALED(status)){
1641
fprintf_plus(stderr, "Warning: network hook \"%s\" died by"
1642
" signal %d\n", direntry->d_name,
1647
fprintf_plus(stderr, "Warning: network hook \"%s\""
1648
" crashed\n", direntry->d_name);
1655
fprintf_plus(stderr, "Network hook \"%s\" ran successfully\n",
1663
__attribute__((nonnull, warn_unused_result))
1664
error_t bring_up_interface(const char *const interface,
1666
error_t old_errno = errno;
1668
struct ifreq network;
1669
unsigned int if_index = if_nametoindex(interface);
1671
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
1681
if(not interface_is_up(interface)){
1682
error_t ret_errno = 0, ioctl_errno = 0;
1683
if(not get_flags(interface, &network)){
1685
fprintf_plus(stderr, "Failed to get flags for interface "
1686
"\"%s\"\n", interface);
1690
network.ifr_flags |= IFF_UP; /* set flag */
1692
int sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1695
perror_plus("socket");
1701
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1703
perror_plus("close");
1710
fprintf_plus(stderr, "Bringing up interface \"%s\"\n",
1714
/* Raise privileges */
1715
ret_errno = raise_privileges();
1716
bool restore_loglevel = false;
1718
perror_plus("Failed to raise privileges");
1723
/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO
1724
messages about the network interface to mess up the prompt */
1725
ret_linux = klogctl(8, NULL, 5);
1726
if(ret_linux == -1){
1727
perror_plus("klogctl");
1729
restore_loglevel = true;
1732
#endif /* __linux__ */
1733
int ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
1734
ioctl_errno = errno;
1736
if(restore_loglevel){
1737
ret_linux = klogctl(7, NULL, 0);
1738
if(ret_linux == -1){
1739
perror_plus("klogctl");
1742
#endif /* __linux__ */
1744
/* If raise_privileges() succeeded above */
1746
/* Lower privileges */
1747
ret_errno = lower_privileges();
1750
perror_plus("Failed to lower privileges");
1754
/* Close the socket */
1755
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1757
perror_plus("close");
1760
if(ret_setflags == -1){
1761
errno = ioctl_errno;
1762
perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");
1767
fprintf_plus(stderr, "Interface \"%s\" is already up; good\n",
1771
/* Sleep checking until interface is running.
1772
Check every 0.25s, up to total time of delay */
1773
for(int i=0; i < delay * 4; i++){
1774
if(interface_is_running(interface)){
1028
tmpmax = strtoimax(flagstring, &tmp, 0);
1029
if(errno != 0 or tmp == flagstring or (*tmp != '\0'
1030
and not (isspace(*tmp)))
1031
or tmpmax != (ifreq_flags)tmpmax){
1036
ifreq_flags flags = (ifreq_flags)tmpmax;
1037
/* Reject the loopback device */
1038
if(flags & IFF_LOOPBACK){
1041
/* Accept point-to-point devices only if connect_to is specified */
1042
if(connect_to != NULL and (flags & IFF_POINTOPOINT)){
1045
/* Otherwise, reject non-broadcast-capable devices */
1046
if(not (flags & IFF_BROADCAST)){
1049
/* Accept this device */
1777
struct timespec sleeptime = { .tv_nsec = 250000000 };
1778
ret = nanosleep(&sleeptime, NULL);
1779
if(ret == -1 and errno != EINTR){
1780
perror_plus("nanosleep");
1788
__attribute__((nonnull, warn_unused_result))
1789
error_t take_down_interface(const char *const interface){
1790
error_t old_errno = errno;
1791
struct ifreq network;
1792
unsigned int if_index = if_nametoindex(interface);
1794
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
1798
if(interface_is_up(interface)){
1799
error_t ret_errno = 0, ioctl_errno = 0;
1800
if(not get_flags(interface, &network) and debug){
1802
fprintf_plus(stderr, "Failed to get flags for interface "
1803
"\"%s\"\n", interface);
1807
network.ifr_flags &= ~(short)IFF_UP; /* clear flag */
1809
int sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1812
perror_plus("socket");
1818
fprintf_plus(stderr, "Taking down interface \"%s\"\n",
1822
/* Raise privileges */
1823
ret_errno = raise_privileges();
1825
perror_plus("Failed to raise privileges");
1827
int ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
1828
ioctl_errno = errno;
1830
/* If raise_privileges() succeeded above */
1832
/* Lower privileges */
1833
ret_errno = lower_privileges();
1836
perror_plus("Failed to lower privileges");
1840
/* Close the socket */
1841
int ret = (int)TEMP_FAILURE_RETRY(close(sd));
1843
perror_plus("close");
1846
if(ret_setflags == -1){
1847
errno = ioctl_errno;
1848
perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");
1853
fprintf_plus(stderr, "Interface \"%s\" is already down; odd\n",
1053
1861
int main(int argc, char *argv[]){
1862
mandos_context mc = { .server = NULL, .dh_bits = 1024,
1863
.priority = "SECURE256:!CTYPE-X.509:"
1864
"+CTYPE-OPENPGP", .current_server = NULL,
1865
.interfaces = NULL, .interfaces_size = 0 };
1054
1866
AvahiSServiceBrowser *sb = NULL;
1057
1869
intmax_t tmpmax;
1059
1871
int exitcode = EXIT_SUCCESS;
1060
const char *interface = "";
1061
struct ifreq network;
1063
bool take_down_interface = false;
1872
char *interfaces_to_take_down = NULL;
1873
size_t interfaces_to_take_down_size = 0;
1066
1874
char tempdir[] = "/tmp/mandosXXXXXX";
1067
1875
bool tempdir_created = false;
1068
1876
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
1069
1877
const char *seckey = PATHDIR "/" SECKEY;
1070
1878
const char *pubkey = PATHDIR "/" PUBKEY;
1879
char *interfaces_hooks = NULL;
1072
1881
bool gnutls_initialized = false;
1073
1882
bool gpgme_initialized = false;
1074
1883
float delay = 2.5f;
1884
double retry_interval = 10; /* 10s between trying a server and
1885
retrying the same server again */
1076
1887
struct sigaction old_sigterm_action = { .sa_handler = SIG_DFL };
1077
1888
struct sigaction sigterm_action = { .sa_handler = handle_sigterm };
1170
2002
delay = strtof(arg, &tmp);
1171
2003
if(errno != 0 or tmp == arg or *tmp != '\0'){
1172
fprintf(stderr, "Bad delay\n");
2004
argp_error(state, "Bad delay");
2006
case 132: /* --retry */
2008
retry_interval = strtod(arg, &tmp);
2009
if(errno != 0 or tmp == arg or *tmp != '\0'
2010
or (retry_interval * 1000) > INT_MAX
2011
or retry_interval < 0){
2012
argp_error(state, "Bad retry interval");
2015
case 133: /* --network-hook-dir */
2019
* These reproduce what we would get without ARGP_NO_HELP
2021
case '?': /* --help */
2022
argp_state_help(state, state->out_stream,
2023
(ARGP_HELP_STD_HELP | ARGP_HELP_EXIT_ERR)
2024
& ~(unsigned int)ARGP_HELP_EXIT_OK);
2025
case -3: /* --usage */
2026
argp_state_help(state, state->out_stream,
2027
ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);
2028
case 'V': /* --version */
2029
fprintf_plus(state->out_stream, "%s\n", argp_program_version);
2030
exit(argp_err_exit_status);
1181
2033
return ARGP_ERR_UNKNOWN;
1186
2038
struct argp argp = { .options = options, .parser = parse_opt,
1187
2039
.args_doc = "",
1188
2040
.doc = "Mandos client -- Get and decrypt"
1189
2041
" passwords from a Mandos server" };
1190
ret = argp_parse(&argp, argc, argv, 0, 0, NULL);
1191
if(ret == ARGP_ERR_UNKNOWN){
1192
fprintf(stderr, "Unknown error while parsing arguments\n");
1193
exitcode = EXIT_FAILURE;
2042
ret = argp_parse(&argp, argc, argv,
2043
ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);
2050
perror_plus("argp_parse");
2051
exitcode = EX_OSERR;
2054
exitcode = EX_USAGE;
2060
/* Work around Debian bug #633582:
2061
<http://bugs.debian.org/633582> */
2063
/* Re-raise privileges */
2064
ret_errno = raise_privileges();
2067
perror_plus("Failed to raise privileges");
2071
if(strcmp(seckey, PATHDIR "/" SECKEY) == 0){
2072
int seckey_fd = open(seckey, O_RDONLY);
2073
if(seckey_fd == -1){
2074
perror_plus("open");
2076
ret = (int)TEMP_FAILURE_RETRY(fstat(seckey_fd, &st));
2078
perror_plus("fstat");
2080
if(S_ISREG(st.st_mode)
2081
and st.st_uid == 0 and st.st_gid == 0){
2082
ret = fchown(seckey_fd, uid, gid);
2084
perror_plus("fchown");
2088
TEMP_FAILURE_RETRY(close(seckey_fd));
2092
if(strcmp(pubkey, PATHDIR "/" PUBKEY) == 0){
2093
int pubkey_fd = open(pubkey, O_RDONLY);
2094
if(pubkey_fd == -1){
2095
perror_plus("open");
2097
ret = (int)TEMP_FAILURE_RETRY(fstat(pubkey_fd, &st));
2099
perror_plus("fstat");
2101
if(S_ISREG(st.st_mode)
2102
and st.st_uid == 0 and st.st_gid == 0){
2103
ret = fchown(pubkey_fd, uid, gid);
2105
perror_plus("fchown");
2109
TEMP_FAILURE_RETRY(close(pubkey_fd));
2113
/* Lower privileges */
2114
ret_errno = lower_privileges();
2117
perror_plus("Failed to lower privileges");
2122
/* Remove invalid interface names (except "none") */
2124
char *interface = NULL;
2125
while((interface = argz_next(mc.interfaces, mc.interfaces_size,
2127
if(strcmp(interface, "none") != 0
2128
and if_nametoindex(interface) == 0){
2129
if(interface[0] != '\0'){
2130
fprintf_plus(stderr, "Not using nonexisting interface"
2131
" \"%s\"\n", interface);
2133
argz_delete(&mc.interfaces, &mc.interfaces_size, interface);
2139
/* Run network hooks */
2141
if(mc.interfaces != NULL){
2142
interfaces_hooks = malloc(mc.interfaces_size);
2143
if(interfaces_hooks == NULL){
2144
perror_plus("malloc");
2147
memcpy(interfaces_hooks, mc.interfaces, mc.interfaces_size);
2148
argz_stringify(interfaces_hooks, mc.interfaces_size, (int)',');
2150
run_network_hooks("start", interfaces_hooks != NULL ?
2151
interfaces_hooks : "", delay);
1199
2155
avahi_set_log_function(empty_log);
1202
if(interface[0] == '\0'){
1203
struct dirent **direntries;
1204
ret = scandir(sys_class_net, &direntries, good_interface,
1207
/* Pick the first good interface */
1208
interface = strdup(direntries[0]->d_name);
1209
if(interface == NULL){
1212
exitcode = EXIT_FAILURE;
1218
fprintf(stderr, "Could not find a network interface\n");
1219
exitcode = EXIT_FAILURE;
1224
2158
/* Initialize Avahi early so avahi_simple_poll_quit() can be called
1225
2159
from the signal handler */
1226
2160
/* Initialize the pseudo-RNG for Avahi */
1227
2161
srand((unsigned int) time(NULL));
1228
mc.simple_poll = avahi_simple_poll_new();
1229
if(mc.simple_poll == NULL){
1230
fprintf(stderr, "Avahi: Failed to create simple poll object.\n");
1231
exitcode = EXIT_FAILURE;
2162
simple_poll = avahi_simple_poll_new();
2163
if(simple_poll == NULL){
2164
fprintf_plus(stderr,
2165
"Avahi: Failed to create simple poll object.\n");
2166
exitcode = EX_UNAVAILABLE;
1235
2170
sigemptyset(&sigterm_action.sa_mask);
1236
2171
ret = sigaddset(&sigterm_action.sa_mask, SIGINT);
1238
perror("sigaddset");
1239
exitcode = EXIT_FAILURE;
2173
perror_plus("sigaddset");
2174
exitcode = EX_OSERR;
1242
2177
ret = sigaddset(&sigterm_action.sa_mask, SIGHUP);
1244
perror("sigaddset");
1245
exitcode = EXIT_FAILURE;
2179
perror_plus("sigaddset");
2180
exitcode = EX_OSERR;
1248
2183
ret = sigaddset(&sigterm_action.sa_mask, SIGTERM);
1250
perror("sigaddset");
1251
exitcode = EXIT_FAILURE;
2185
perror_plus("sigaddset");
2186
exitcode = EX_OSERR;
1254
2189
/* Need to check if the handler is SIG_IGN before handling:
1258
2193
ret = sigaction(SIGINT, NULL, &old_sigterm_action);
1260
perror("sigaction");
1261
return EXIT_FAILURE;
2195
perror_plus("sigaction");
1263
2198
if(old_sigterm_action.sa_handler != SIG_IGN){
1264
2199
ret = sigaction(SIGINT, &sigterm_action, NULL);
1266
perror("sigaction");
1267
exitcode = EXIT_FAILURE;
2201
perror_plus("sigaction");
2202
exitcode = EX_OSERR;
1271
2206
ret = sigaction(SIGHUP, NULL, &old_sigterm_action);
1273
perror("sigaction");
1274
return EXIT_FAILURE;
2208
perror_plus("sigaction");
1276
2211
if(old_sigterm_action.sa_handler != SIG_IGN){
1277
2212
ret = sigaction(SIGHUP, &sigterm_action, NULL);
1279
perror("sigaction");
1280
exitcode = EXIT_FAILURE;
2214
perror_plus("sigaction");
2215
exitcode = EX_OSERR;
1284
2219
ret = sigaction(SIGTERM, NULL, &old_sigterm_action);
1286
perror("sigaction");
1287
return EXIT_FAILURE;
2221
perror_plus("sigaction");
1289
2224
if(old_sigterm_action.sa_handler != SIG_IGN){
1290
2225
ret = sigaction(SIGTERM, &sigterm_action, NULL);
1292
perror("sigaction");
1293
exitcode = EXIT_FAILURE;
1298
/* If the interface is down, bring it up */
1299
if(strcmp(interface, "none") != 0){
1300
if_index = (AvahiIfIndex) if_nametoindex(interface);
1302
fprintf(stderr, "No such interface: \"%s\"\n", interface);
1303
exitcode = EXIT_FAILURE;
1311
/* Re-raise priviliges */
1319
/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO
1320
messages to mess up the prompt */
1321
ret = klogctl(8, NULL, 5);
1322
bool restore_loglevel = true;
1324
restore_loglevel = false;
1327
#endif /* __linux__ */
1329
sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1332
exitcode = EXIT_FAILURE;
1334
if(restore_loglevel){
1335
ret = klogctl(7, NULL, 0);
1340
#endif /* __linux__ */
1341
/* Lower privileges */
1349
strcpy(network.ifr_name, interface);
1350
ret = ioctl(sd, SIOCGIFFLAGS, &network);
1352
perror("ioctl SIOCGIFFLAGS");
1354
if(restore_loglevel){
1355
ret = klogctl(7, NULL, 0);
1360
#endif /* __linux__ */
1361
exitcode = EXIT_FAILURE;
1362
/* Lower privileges */
1370
if((network.ifr_flags & IFF_UP) == 0){
1371
network.ifr_flags |= IFF_UP;
1372
take_down_interface = true;
1373
ret = ioctl(sd, SIOCSIFFLAGS, &network);
1375
take_down_interface = false;
1376
perror("ioctl SIOCSIFFLAGS");
1377
exitcode = EXIT_FAILURE;
1379
if(restore_loglevel){
1380
ret = klogctl(7, NULL, 0);
2227
perror_plus("sigaction");
2228
exitcode = EX_OSERR;
2233
/* If no interfaces were specified, make a list */
2234
if(mc.interfaces == NULL){
2235
struct dirent **direntries;
2236
/* Look for any good interfaces */
2237
ret = scandir(sys_class_net, &direntries, good_interface,
2240
/* Add all found interfaces to interfaces list */
2241
for(int i = 0; i < ret; ++i){
2242
ret_errno = argz_add(&mc.interfaces, &mc.interfaces_size,
2243
direntries[i]->d_name);
2246
perror_plus("argz_add");
2250
fprintf_plus(stderr, "Will use interface \"%s\"\n",
2251
direntries[i]->d_name);
2257
fprintf_plus(stderr, "Could not find a network interface\n");
2258
exitcode = EXIT_FAILURE;
2263
/* Bring up interfaces which are down, and remove any "none"s */
2265
char *interface = NULL;
2266
while((interface = argz_next(mc.interfaces, mc.interfaces_size,
2268
/* If interface name is "none", stop bringing up interfaces.
2269
Also remove all instances of "none" from the list */
2270
if(strcmp(interface, "none") == 0){
2271
argz_delete(&mc.interfaces, &mc.interfaces_size,
2274
while((interface = argz_next(mc.interfaces,
2275
mc.interfaces_size, interface))){
2276
if(strcmp(interface, "none") == 0){
2277
argz_delete(&mc.interfaces, &mc.interfaces_size,
1385
#endif /* __linux__ */
1386
/* Lower privileges */
1395
/* sleep checking until interface is running */
1396
for(int i=0; i < delay * 4; i++){
1397
ret = ioctl(sd, SIOCGIFFLAGS, &network);
1399
perror("ioctl SIOCGIFFLAGS");
1400
} else if(network.ifr_flags & IFF_RUNNING){
1403
struct timespec sleeptime = { .tv_nsec = 250000000 };
1404
ret = nanosleep(&sleeptime, NULL);
1405
if(ret == -1 and errno != EINTR){
1406
perror("nanosleep");
1409
if(not take_down_interface){
1410
/* We won't need the socket anymore */
1411
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1417
if(restore_loglevel){
1418
/* Restores kernel loglevel to default */
1419
ret = klogctl(7, NULL, 0);
1424
#endif /* __linux__ */
1425
/* Lower privileges */
1427
if(take_down_interface){
1428
/* Lower privileges */
1434
/* Lower privileges permanently */
2284
bool interface_was_up = interface_is_up(interface);
2285
errno = bring_up_interface(interface, delay);
2286
if(not interface_was_up){
2288
perror_plus("Failed to bring up interface");
2290
errno = argz_add(&interfaces_to_take_down,
2291
&interfaces_to_take_down_size,
2294
perror_plus("argz_add");
2299
if(debug and (interfaces_to_take_down == NULL)){
2300
fprintf_plus(stderr, "No interfaces were brought up\n");
2304
/* If we only got one interface, explicitly use only that one */
2305
if(argz_count(mc.interfaces, mc.interfaces_size) == 1){
2307
fprintf_plus(stderr, "Using only interface \"%s\"\n",
2310
if_index = (AvahiIfIndex)if_nametoindex(mc.interfaces);
1446
ret = init_gnutls_global(pubkey, seckey);
2317
ret = init_gnutls_global(pubkey, seckey, &mc);
1448
fprintf(stderr, "init_gnutls_global failed\n");
1449
exitcode = EXIT_FAILURE;
2319
fprintf_plus(stderr, "init_gnutls_global failed\n");
2320
exitcode = EX_UNAVAILABLE;
1452
2323
gnutls_initialized = true;