26
26
* along with this program. If not, see
27
27
* <http://www.gnu.org/licenses/>.
29
* Contact the authors at <mandos@fukt.bsnet.se>.
29
* Contact the authors at <mandos@recompile.se>.
32
32
/* Needed by GPGME, specifically gpgme_data_seek() */
33
#ifndef _LARGEFILE_SOURCE
33
34
#define _LARGEFILE_SOURCE
36
#ifndef _FILE_OFFSET_BITS
34
37
#define _FILE_OFFSET_BITS 64
36
40
#define _GNU_SOURCE /* TEMP_FAILURE_RETRY(), asprintf() */
38
42
#include <stdio.h> /* fprintf(), stderr, fwrite(),
39
stdout, ferror(), sscanf(),
41
#include <stdint.h> /* uint16_t, uint32_t */
43
stdout, ferror(), remove() */
44
#include <stdint.h> /* uint16_t, uint32_t, intptr_t */
42
45
#include <stddef.h> /* NULL, size_t, ssize_t */
43
#include <stdlib.h> /* free(), EXIT_SUCCESS, EXIT_FAILURE,
45
#include <stdbool.h> /* bool, true */
46
#include <stdlib.h> /* free(), EXIT_SUCCESS, srand(),
48
#include <stdbool.h> /* bool, false, true */
46
49
#include <string.h> /* memset(), strcmp(), strlen(),
47
50
strerror(), asprintf(), strcpy() */
48
#include <sys/ioctl.h> /* ioctl */
51
#include <sys/ioctl.h> /* ioctl */
49
52
#include <sys/types.h> /* socket(), inet_pton(), sockaddr,
50
53
sockaddr_in6, PF_INET6,
51
SOCK_STREAM, INET6_ADDRSTRLEN,
52
uid_t, gid_t, open(), opendir(),
54
#include <sys/stat.h> /* open() */
54
SOCK_STREAM, uid_t, gid_t, open(),
56
#include <sys/stat.h> /* open(), S_ISREG */
55
57
#include <sys/socket.h> /* socket(), struct sockaddr_in6,
56
struct in6_addr, inet_pton(),
58
inet_pton(), connect() */
58
59
#include <fcntl.h> /* open() */
59
60
#include <dirent.h> /* opendir(), struct dirent, readdir()
61
#include <inttypes.h> /* PRIu16, intmax_t, SCNdMAX */
62
#include <inttypes.h> /* PRIu16, PRIdMAX, intmax_t,
62
64
#include <assert.h> /* assert() */
63
#include <errno.h> /* perror(), errno */
64
#include <time.h> /* nanosleep(), time() */
65
#include <errno.h> /* perror(), errno,
66
program_invocation_short_name */
67
#include <time.h> /* nanosleep(), time(), sleep() */
65
68
#include <net/if.h> /* ioctl, ifreq, SIOCGIFFLAGS, IFF_UP,
66
69
SIOCSIFFLAGS, if_indextoname(),
67
70
if_nametoindex(), IF_NAMESIZE */
68
#include <netinet/in.h>
71
#include <netinet/in.h> /* IN6_IS_ADDR_LINKLOCAL,
72
INET_ADDRSTRLEN, INET6_ADDRSTRLEN
69
74
#include <unistd.h> /* close(), SEEK_SET, off_t, write(),
70
getuid(), getgid(), setuid(),
72
#include <arpa/inet.h> /* inet_pton(), htons */
73
#include <iso646.h> /* not, and, or */
75
getuid(), getgid(), seteuid(),
76
setgid(), pause(), _exit() */
77
#include <arpa/inet.h> /* inet_pton(), htons, inet_ntop() */
78
#include <iso646.h> /* not, or, and */
74
79
#include <argp.h> /* struct argp_option, error_t, struct
75
80
argp_state, struct argp,
76
81
argp_parse(), ARGP_KEY_ARG,
77
82
ARGP_KEY_END, ARGP_ERR_UNKNOWN */
83
#include <signal.h> /* sigemptyset(), sigaddset(),
84
sigaction(), SIGTERM, sig_atomic_t,
86
#include <sysexits.h> /* EX_OSERR, EX_USAGE, EX_UNAVAILABLE,
87
EX_NOHOST, EX_IOERR, EX_PROTOCOL */
88
#include <sys/wait.h> /* waitpid(), WIFEXITED(),
89
WEXITSTATUS(), WTERMSIG() */
90
#include <grp.h> /* setgroups() */
91
#include <argz.h> /* argz_add_sep(), argz_next(),
92
argz_delete(), argz_append(),
93
argz_stringify(), argz_add(),
79
97
#include <sys/klog.h> /* klogctl() */
98
#endif /* __linux__ */
83
101
/* All Avahi types, constants and functions
254
356
ssize_t plaintext_length = 0;
257
fprintf(stderr, "Trying to decrypt OpenPGP data\n");
359
fprintf_plus(stderr, "Trying to decrypt OpenPGP data\n");
260
362
/* Create new GPGME data buffer from memory cryptotext */
261
363
rc = gpgme_data_new_from_mem(&dh_crypto, cryptotext, crypto_size,
263
365
if(rc != GPG_ERR_NO_ERROR){
264
fprintf(stderr, "bad gpgme_data_new_from_mem: %s: %s\n",
265
gpgme_strsource(rc), gpgme_strerror(rc));
366
fprintf_plus(stderr, "bad gpgme_data_new_from_mem: %s: %s\n",
367
gpgme_strsource(rc), gpgme_strerror(rc));
269
371
/* Create new empty GPGME data buffer for the plaintext */
270
372
rc = gpgme_data_new(&dh_plain);
271
373
if(rc != GPG_ERR_NO_ERROR){
272
fprintf(stderr, "bad gpgme_data_new: %s: %s\n",
273
gpgme_strsource(rc), gpgme_strerror(rc));
374
fprintf_plus(stderr, "Mandos plugin mandos-client: "
375
"bad gpgme_data_new: %s: %s\n",
376
gpgme_strsource(rc), gpgme_strerror(rc));
274
377
gpgme_data_release(dh_crypto);
278
381
/* Decrypt data from the cryptotext data buffer to the plaintext
280
rc = gpgme_op_decrypt(mc->ctx, dh_crypto, dh_plain);
383
rc = gpgme_op_decrypt(mc.ctx, dh_crypto, dh_plain);
281
384
if(rc != GPG_ERR_NO_ERROR){
282
fprintf(stderr, "bad gpgme_op_decrypt: %s: %s\n",
283
gpgme_strsource(rc), gpgme_strerror(rc));
385
fprintf_plus(stderr, "bad gpgme_op_decrypt: %s: %s\n",
386
gpgme_strsource(rc), gpgme_strerror(rc));
284
387
plaintext_length = -1;
286
389
gpgme_decrypt_result_t result;
287
result = gpgme_op_decrypt_result(mc->ctx);
390
result = gpgme_op_decrypt_result(mc.ctx);
288
391
if(result == NULL){
289
fprintf(stderr, "gpgme_op_decrypt_result failed\n");
392
fprintf_plus(stderr, "gpgme_op_decrypt_result failed\n");
291
fprintf(stderr, "Unsupported algorithm: %s\n",
292
result->unsupported_algorithm);
293
fprintf(stderr, "Wrong key usage: %u\n",
294
result->wrong_key_usage);
394
fprintf_plus(stderr, "Unsupported algorithm: %s\n",
395
result->unsupported_algorithm);
396
fprintf_plus(stderr, "Wrong key usage: %u\n",
397
result->wrong_key_usage);
295
398
if(result->file_name != NULL){
296
fprintf(stderr, "File name: %s\n", result->file_name);
399
fprintf_plus(stderr, "File name: %s\n", result->file_name);
298
401
gpgme_recipient_t recipient;
299
402
recipient = result->recipients;
301
while(recipient != NULL){
302
fprintf(stderr, "Public key algorithm: %s\n",
303
gpgme_pubkey_algo_name(recipient->pubkey_algo));
304
fprintf(stderr, "Key ID: %s\n", recipient->keyid);
305
fprintf(stderr, "Secret key available: %s\n",
306
recipient->status == GPG_ERR_NO_SECKEY
308
recipient = recipient->next;
403
while(recipient != NULL){
404
fprintf_plus(stderr, "Public key algorithm: %s\n",
405
gpgme_pubkey_algo_name
406
(recipient->pubkey_algo));
407
fprintf_plus(stderr, "Key ID: %s\n", recipient->keyid);
408
fprintf_plus(stderr, "Secret key available: %s\n",
409
recipient->status == GPG_ERR_NO_SECKEY
411
recipient = recipient->next;
409
510
/* OpenPGP credentials */
410
gnutls_certificate_allocate_credentials(&mc->cred);
511
ret = gnutls_certificate_allocate_credentials(&mc.cred);
411
512
if(ret != GNUTLS_E_SUCCESS){
412
fprintf(stderr, "GnuTLS memory error: %s\n", /* Spurious warning
416
safer_gnutls_strerror(ret));
513
fprintf_plus(stderr, "GnuTLS memory error: %s\n",
514
safer_gnutls_strerror(ret));
417
515
gnutls_global_deinit();
422
fprintf(stderr, "Attempting to use OpenPGP public key %s and"
423
" secret key %s as GnuTLS credentials\n", pubkeyfilename,
520
fprintf_plus(stderr, "Attempting to use OpenPGP public key %s and"
521
" secret key %s as GnuTLS credentials\n",
427
526
ret = gnutls_certificate_set_openpgp_key_file
428
(mc->cred, pubkeyfilename, seckeyfilename,
527
(mc.cred, pubkeyfilename, seckeyfilename,
429
528
GNUTLS_OPENPGP_FMT_BASE64);
430
529
if(ret != GNUTLS_E_SUCCESS){
432
"Error[%d] while reading the OpenPGP key pair ('%s',"
433
" '%s')\n", ret, pubkeyfilename, seckeyfilename);
434
fprintf(stderr, "The GnuTLS error is: %s\n",
435
safer_gnutls_strerror(ret));
531
"Error[%d] while reading the OpenPGP key pair ('%s',"
532
" '%s')\n", ret, pubkeyfilename, seckeyfilename);
533
fprintf_plus(stderr, "The GnuTLS error is: %s\n",
534
safer_gnutls_strerror(ret));
439
538
/* GnuTLS server initialization */
440
ret = gnutls_dh_params_init(&mc->dh_params);
539
ret = gnutls_dh_params_init(&mc.dh_params);
441
540
if(ret != GNUTLS_E_SUCCESS){
442
fprintf(stderr, "Error in GnuTLS DH parameter initialization:"
443
" %s\n", safer_gnutls_strerror(ret));
541
fprintf_plus(stderr, "Error in GnuTLS DH parameter"
542
" initialization: %s\n",
543
safer_gnutls_strerror(ret));
446
ret = gnutls_dh_params_generate2(mc->dh_params, mc->dh_bits);
546
ret = gnutls_dh_params_generate2(mc.dh_params, mc.dh_bits);
447
547
if(ret != GNUTLS_E_SUCCESS){
448
fprintf(stderr, "Error in GnuTLS prime generation: %s\n",
449
safer_gnutls_strerror(ret));
548
fprintf_plus(stderr, "Error in GnuTLS prime generation: %s\n",
549
safer_gnutls_strerror(ret));
453
gnutls_certificate_set_dh_params(mc->cred, mc->dh_params);
553
gnutls_certificate_set_dh_params(mc.cred, mc.dh_params);
459
gnutls_certificate_free_credentials(mc->cred);
559
gnutls_certificate_free_credentials(mc.cred);
460
560
gnutls_global_deinit();
461
gnutls_dh_params_deinit(mc->dh_params);
561
gnutls_dh_params_deinit(mc.dh_params);
465
static int init_gnutls_session(mandos_context *mc,
466
gnutls_session_t *session){
565
static int init_gnutls_session(gnutls_session_t *session){
468
567
/* GnuTLS session creation */
469
ret = gnutls_init(session, GNUTLS_SERVER);
569
ret = gnutls_init(session, GNUTLS_SERVER);
573
} while(ret == GNUTLS_E_INTERRUPTED or ret == GNUTLS_E_AGAIN);
470
574
if(ret != GNUTLS_E_SUCCESS){
471
fprintf(stderr, "Error in GnuTLS session initialization: %s\n",
472
safer_gnutls_strerror(ret));
576
"Error in GnuTLS session initialization: %s\n",
577
safer_gnutls_strerror(ret));
477
ret = gnutls_priority_set_direct(*session, mc->priority, &err);
583
ret = gnutls_priority_set_direct(*session, mc.priority, &err);
585
gnutls_deinit(*session);
588
} while(ret == GNUTLS_E_INTERRUPTED or ret == GNUTLS_E_AGAIN);
478
589
if(ret != GNUTLS_E_SUCCESS){
479
fprintf(stderr, "Syntax error at: %s\n", err);
480
fprintf(stderr, "GnuTLS error: %s\n",
481
safer_gnutls_strerror(ret));
590
fprintf_plus(stderr, "Syntax error at: %s\n", err);
591
fprintf_plus(stderr, "GnuTLS error: %s\n",
592
safer_gnutls_strerror(ret));
482
593
gnutls_deinit(*session);
487
ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,
599
ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,
602
gnutls_deinit(*session);
605
} while(ret == GNUTLS_E_INTERRUPTED or ret == GNUTLS_E_AGAIN);
489
606
if(ret != GNUTLS_E_SUCCESS){
490
fprintf(stderr, "Error setting GnuTLS credentials: %s\n",
491
safer_gnutls_strerror(ret));
607
fprintf_plus(stderr, "Error setting GnuTLS credentials: %s\n",
608
safer_gnutls_strerror(ret));
492
609
gnutls_deinit(*session);
496
613
/* ignore client certificate if any. */
497
gnutls_certificate_server_set_request(*session,
614
gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);
500
gnutls_dh_set_prime_bits(*session, mc->dh_bits);
616
gnutls_dh_set_prime_bits(*session, mc.dh_bits);
509
625
/* Called when a Mandos server is found */
510
626
static int start_mandos_communication(const char *ip, uint16_t port,
511
627
AvahiIfIndex if_index,
629
int ret, tcp_sd = -1;
515
union { struct sockaddr in; struct sockaddr_in6 in6; } to;
632
struct sockaddr_in in;
633
struct sockaddr_in6 in6;
516
635
char *buffer = NULL;
517
char *decrypted_buffer;
636
char *decrypted_buffer = NULL;
518
637
size_t buffer_length = 0;
519
638
size_t buffer_capacity = 0;
520
ssize_t decrypted_buffer_size;
523
char interface[IF_NAMESIZE];
524
641
gnutls_session_t session;
526
ret = init_gnutls_session(mc, &session);
642
int pf; /* Protocol family */
659
fprintf_plus(stderr, "Bad address family: %d\n", af);
664
ret = init_gnutls_session(&session);
532
fprintf(stderr, "Setting up a tcp connection to %s, port %" PRIu16
670
fprintf_plus(stderr, "Setting up a TCP connection to %s, port %"
671
PRIu16 "\n", ip, port);
536
tcp_sd = socket(PF_INET6, SOCK_STREAM, 0);
674
tcp_sd = socket(pf, SOCK_STREAM, 0);
677
perror_plus("socket");
543
if(if_indextoname((unsigned int)if_index, interface) == NULL){
544
perror("if_indextoname");
547
fprintf(stderr, "Binding to interface %s\n", interface);
550
687
memset(&to, 0, sizeof(to));
551
to.in6.sin6_family = AF_INET6;
552
/* It would be nice to have a way to detect if we were passed an
553
IPv4 address here. Now we assume an IPv6 address. */
554
ret = inet_pton(AF_INET6, ip, &to.in6.sin6_addr);
689
to.in6.sin6_family = (sa_family_t)af;
690
ret = inet_pton(af, ip, &to.in6.sin6_addr);
692
to.in.sin_family = (sa_family_t)af;
693
ret = inet_pton(af, ip, &to.in.sin_addr);
697
perror_plus("inet_pton");
560
fprintf(stderr, "Bad address: %s\n", ip);
703
fprintf_plus(stderr, "Bad address: %s\n", ip);
563
to.in6.sin6_port = htons(port); /* Spurious warnings from
708
to.in6.sin6_port = htons(port); /* Spurious warnings from
710
-Wunreachable-code */
712
if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */
713
(&to.in6.sin6_addr)){ /* -Wstrict-aliasing=2 or lower and
715
if(if_index == AVAHI_IF_UNSPEC){
716
fprintf_plus(stderr, "An IPv6 link-local address is"
717
" incomplete without a network interface\n");
721
/* Set the network interface number as scope */
722
to.in6.sin6_scope_id = (uint32_t)if_index;
725
to.in.sin_port = htons(port); /* Spurious warnings from
565
727
-Wunreachable-code */
567
to.in6.sin6_scope_id = (uint32_t)if_index;
570
fprintf(stderr, "Connection to: %s, port %" PRIu16 "\n", ip,
572
char addrstr[INET6_ADDRSTRLEN] = "";
573
if(inet_ntop(to.in6.sin6_family, &(to.in6.sin6_addr), addrstr,
574
sizeof(addrstr)) == NULL){
736
if(af == AF_INET6 and if_index != AVAHI_IF_UNSPEC){
737
char interface[IF_NAMESIZE];
738
if(if_indextoname((unsigned int)if_index, interface) == NULL){
739
perror_plus("if_indextoname");
741
fprintf_plus(stderr, "Connection to: %s%%%s, port %" PRIu16
742
"\n", ip, interface, port);
745
fprintf_plus(stderr, "Connection to: %s, port %" PRIu16 "\n",
748
char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?
749
INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";
752
pcret = inet_ntop(af, &(to.in6.sin6_addr), addrstr,
755
pcret = inet_ntop(af, &(to.in.sin_addr), addrstr,
759
perror_plus("inet_ntop");
577
761
if(strcmp(addrstr, ip) != 0){
578
fprintf(stderr, "Canonical address form: %s\n", addrstr);
762
fprintf_plus(stderr, "Canonical address form: %s\n", addrstr);
583
ret = connect(tcp_sd, &to.in, sizeof(to));
773
ret = connect(tcp_sd, &to.in6, sizeof(to));
775
ret = connect(tcp_sd, &to.in, sizeof(to)); /* IPv4 */
778
if ((errno != ECONNREFUSED and errno != ENETUNREACH) or debug){
780
perror_plus("connect");
589
791
const char *out = mandos_protocol_version;
815
1101
case AVAHI_BROWSER_ALL_FOR_NOW:
816
1102
case AVAHI_BROWSER_CACHE_EXHAUSTED:
818
fprintf(stderr, "No Mandos server found, still searching...\n");
1104
fprintf_plus(stderr, "No Mandos server found, still"
1111
/* Signal handler that stops main loop after SIGTERM */
1112
static void handle_sigterm(int sig){
1117
signal_received = sig;
1118
int old_errno = errno;
1119
/* set main loop to exit */
1120
if(mc.simple_poll != NULL){
1121
avahi_simple_poll_quit(mc.simple_poll);
1126
bool get_flags(const char *ifname, struct ifreq *ifr){
1130
int s = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1133
perror_plus("socket");
1137
strcpy(ifr->ifr_name, ifname);
1138
ret = ioctl(s, SIOCGIFFLAGS, ifr);
1142
perror_plus("ioctl SIOCGIFFLAGS");
1150
bool good_flags(const char *ifname, const struct ifreq *ifr){
1152
/* Reject the loopback device */
1153
if(ifr->ifr_flags & IFF_LOOPBACK){
1155
fprintf_plus(stderr, "Rejecting loopback interface \"%s\"\n",
1160
/* Accept point-to-point devices only if connect_to is specified */
1161
if(connect_to != NULL and (ifr->ifr_flags & IFF_POINTOPOINT)){
1163
fprintf_plus(stderr, "Accepting point-to-point interface"
1164
" \"%s\"\n", ifname);
1168
/* Otherwise, reject non-broadcast-capable devices */
1169
if(not (ifr->ifr_flags & IFF_BROADCAST)){
1171
fprintf_plus(stderr, "Rejecting non-broadcast interface"
1172
" \"%s\"\n", ifname);
1176
/* Reject non-ARP interfaces (including dummy interfaces) */
1177
if(ifr->ifr_flags & IFF_NOARP){
1179
fprintf_plus(stderr, "Rejecting non-ARP interface \"%s\"\n",
1185
/* Accept this device */
1187
fprintf_plus(stderr, "Interface \"%s\" is good\n", ifname);
1193
* This function determines if a directory entry in /sys/class/net
1194
* corresponds to an acceptable network device.
1195
* (This function is passed to scandir(3) as a filter function.)
1197
int good_interface(const struct dirent *if_entry){
1198
if(if_entry->d_name[0] == '.'){
1203
if(not get_flags(if_entry->d_name, &ifr)){
1205
fprintf_plus(stderr, "Failed to get flags for interface "
1206
"\"%s\"\n", if_entry->d_name);
1211
if(not good_flags(if_entry->d_name, &ifr)){
1218
* This function determines if a network interface is up.
1220
bool interface_is_up(const char *interface){
1222
if(not get_flags(interface, &ifr)){
1224
fprintf_plus(stderr, "Failed to get flags for interface "
1225
"\"%s\"\n", interface);
1230
return (bool)(ifr.ifr_flags & IFF_UP);
1234
* This function determines if a network interface is running
1236
bool interface_is_running(const char *interface){
1238
if(not get_flags(interface, &ifr)){
1240
fprintf_plus(stderr, "Failed to get flags for interface "
1241
"\"%s\"\n", interface);
1246
return (bool)(ifr.ifr_flags & IFF_RUNNING);
1249
int notdotentries(const struct dirent *direntry){
1250
/* Skip "." and ".." */
1251
if(direntry->d_name[0] == '.'
1252
and (direntry->d_name[1] == '\0'
1253
or (direntry->d_name[1] == '.'
1254
and direntry->d_name[2] == '\0'))){
1260
/* Is this directory entry a runnable program? */
1261
int runnable_hook(const struct dirent *direntry){
1266
if((direntry->d_name)[0] == '\0'){
1271
sret = strspn(direntry->d_name, "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
1272
"abcdefghijklmnopqrstuvwxyz"
1275
if((direntry->d_name)[sret] != '\0'){
1276
/* Contains non-allowed characters */
1278
fprintf_plus(stderr, "Ignoring hook \"%s\" with bad name\n",
1284
char *fullname = NULL;
1285
ret = asprintf(&fullname, "%s/%s", hookdir, direntry->d_name);
1287
perror_plus("asprintf");
1291
ret = stat(fullname, &st);
1294
perror_plus("Could not stat hook");
1298
if(not (S_ISREG(st.st_mode))){
1299
/* Not a regular file */
1301
fprintf_plus(stderr, "Ignoring hook \"%s\" - not a file\n",
1306
if(not (st.st_mode & (S_IXUSR | S_IXGRP | S_IXOTH))){
1307
/* Not executable */
1309
fprintf_plus(stderr, "Ignoring hook \"%s\" - not executable\n",
1315
fprintf_plus(stderr, "Hook \"%s\" is acceptable\n",
1321
int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval){
1323
struct timespec now;
1324
struct timespec waited_time;
1325
intmax_t block_time;
1328
if(mc.current_server == NULL){
1330
fprintf_plus(stderr, "Wait until first server is found."
1333
ret = avahi_simple_poll_iterate(s, -1);
1336
fprintf_plus(stderr, "Check current_server if we should run"
1339
/* the current time */
1340
ret = clock_gettime(CLOCK_MONOTONIC, &now);
1342
perror_plus("clock_gettime");
1345
/* Calculating in ms how long time between now and server
1346
who we visted longest time ago. Now - last seen. */
1347
waited_time.tv_sec = (now.tv_sec
1348
- mc.current_server->last_seen.tv_sec);
1349
waited_time.tv_nsec = (now.tv_nsec
1350
- mc.current_server->last_seen.tv_nsec);
1351
/* total time is 10s/10,000ms.
1352
Converting to s from ms by dividing by 1,000,
1353
and ns to ms by dividing by 1,000,000. */
1354
block_time = ((retry_interval
1355
- ((intmax_t)waited_time.tv_sec * 1000))
1356
- ((intmax_t)waited_time.tv_nsec / 1000000));
1359
fprintf_plus(stderr, "Blocking for %" PRIdMAX " ms\n",
1363
if(block_time <= 0){
1364
ret = start_mandos_communication(mc.current_server->ip,
1365
mc.current_server->port,
1366
mc.current_server->if_index,
1367
mc.current_server->af);
1369
avahi_simple_poll_quit(mc.simple_poll);
1372
ret = clock_gettime(CLOCK_MONOTONIC,
1373
&mc.current_server->last_seen);
1375
perror_plus("clock_gettime");
1378
mc.current_server = mc.current_server->next;
1379
block_time = 0; /* Call avahi to find new Mandos
1380
servers, but don't block */
1383
ret = avahi_simple_poll_iterate(s, (int)block_time);
1386
if (ret > 0 or errno != EINTR){
1387
return (ret != 1) ? ret : 0;
1393
/* Set effective uid to 0, return errno */
1394
error_t raise_privileges(void){
1395
error_t old_errno = errno;
1396
error_t ret_errno = 0;
1397
if(seteuid(0) == -1){
1399
perror_plus("seteuid");
1405
/* Set effective and real user ID to 0. Return errno. */
1406
error_t raise_privileges_permanently(void){
1407
error_t old_errno = errno;
1408
error_t ret_errno = raise_privileges();
1413
if(setuid(0) == -1){
1415
perror_plus("seteuid");
1421
/* Set effective user ID to unprivileged saved user ID */
1422
error_t lower_privileges(void){
1423
error_t old_errno = errno;
1424
error_t ret_errno = 0;
1425
if(seteuid(uid) == -1){
1427
perror_plus("seteuid");
1433
/* Lower privileges permanently */
1434
error_t lower_privileges_permanently(void){
1435
error_t old_errno = errno;
1436
error_t ret_errno = 0;
1437
if(setuid(uid) == -1){
1439
perror_plus("setuid");
1445
bool run_network_hooks(const char *mode, const char *interface,
1447
struct dirent **direntries;
1448
struct dirent *direntry;
1450
int numhooks = scandir(hookdir, &direntries, runnable_hook,
1453
perror_plus("scandir");
1455
int devnull = open("/dev/null", O_RDONLY);
1456
for(int i = 0; i < numhooks; i++){
1457
direntry = direntries[i];
1458
char *fullname = NULL;
1459
ret = asprintf(&fullname, "%s/%s", hookdir, direntry->d_name);
1461
perror_plus("asprintf");
1465
fprintf_plus(stderr, "Running network hook \"%s\"\n",
1468
pid_t hook_pid = fork();
1471
/* Raise privileges */
1472
raise_privileges_permanently();
1477
perror_plus("setgid");
1479
/* Reset supplementary groups */
1481
ret = setgroups(0, NULL);
1483
perror_plus("setgroups");
1485
dup2(devnull, STDIN_FILENO);
1487
dup2(STDERR_FILENO, STDOUT_FILENO);
1488
ret = setenv("MANDOSNETHOOKDIR", hookdir, 1);
1490
perror_plus("setenv");
1493
ret = setenv("DEVICE", interface, 1);
1495
perror_plus("setenv");
1498
ret = setenv("VERBOSITY", debug ? "1" : "0", 1);
1500
perror_plus("setenv");
1503
ret = setenv("MODE", mode, 1);
1505
perror_plus("setenv");
1509
ret = asprintf(&delaystring, "%f", delay);
1511
perror_plus("asprintf");
1514
ret = setenv("DELAY", delaystring, 1);
1517
perror_plus("setenv");
1521
if(connect_to != NULL){
1522
ret = setenv("CONNECT", connect_to, 1);
1524
perror_plus("setenv");
1528
if(execl(fullname, direntry->d_name, mode, NULL) == -1){
1529
perror_plus("execl");
1530
_exit(EXIT_FAILURE);
1534
if(TEMP_FAILURE_RETRY(waitpid(hook_pid, &status, 0)) == -1){
1535
perror_plus("waitpid");
1539
if(WIFEXITED(status)){
1540
if(WEXITSTATUS(status) != 0){
1541
fprintf_plus(stderr, "Warning: network hook \"%s\" exited"
1542
" with status %d\n", direntry->d_name,
1543
WEXITSTATUS(status));
1547
} else if(WIFSIGNALED(status)){
1548
fprintf_plus(stderr, "Warning: network hook \"%s\" died by"
1549
" signal %d\n", direntry->d_name,
1554
fprintf_plus(stderr, "Warning: network hook \"%s\""
1555
" crashed\n", direntry->d_name);
1562
fprintf_plus(stderr, "Network hook \"%s\" ran successfully\n",
1571
error_t bring_up_interface(const char *const interface,
1574
error_t old_errno = errno;
1575
error_t ret_errno = 0;
1576
int ret, ret_setflags;
1577
struct ifreq network;
1578
unsigned int if_index = if_nametoindex(interface);
1580
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
1590
if(not interface_is_up(interface)){
1591
if(not get_flags(interface, &network) and debug){
1593
fprintf_plus(stderr, "Failed to get flags for interface "
1594
"\"%s\"\n", interface);
1597
network.ifr_flags |= IFF_UP;
1599
sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1602
perror_plus("socket");
1614
fprintf_plus(stderr, "Bringing up interface \"%s\"\n",
1618
/* Raise priviliges */
1622
/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO
1623
messages about the network interface to mess up the prompt */
1624
int ret_linux = klogctl(8, NULL, 5);
1625
bool restore_loglevel = true;
1626
if(ret_linux == -1){
1627
restore_loglevel = false;
1628
perror_plus("klogctl");
1630
#endif /* __linux__ */
1631
ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
1634
if(restore_loglevel){
1635
ret_linux = klogctl(7, NULL, 0);
1636
if(ret_linux == -1){
1637
perror_plus("klogctl");
1640
#endif /* __linux__ */
1642
/* Lower privileges */
1645
/* Close the socket */
1646
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1648
perror_plus("close");
1651
if(ret_setflags == -1){
1653
perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");
1658
fprintf_plus(stderr, "Interface \"%s\" is already up; good\n",
1662
/* Sleep checking until interface is running.
1663
Check every 0.25s, up to total time of delay */
1664
for(int i=0; i < delay * 4; i++){
1665
if(interface_is_running(interface)){
1668
struct timespec sleeptime = { .tv_nsec = 250000000 };
1669
ret = nanosleep(&sleeptime, NULL);
1670
if(ret == -1 and errno != EINTR){
1671
perror_plus("nanosleep");
1679
error_t take_down_interface(const char *const interface){
1681
error_t old_errno = errno;
1682
error_t ret_errno = 0;
1683
int ret, ret_setflags;
1684
struct ifreq network;
1685
unsigned int if_index = if_nametoindex(interface);
1687
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
1691
if(interface_is_up(interface)){
1692
if(not get_flags(interface, &network) and debug){
1694
fprintf_plus(stderr, "Failed to get flags for interface "
1695
"\"%s\"\n", interface);
1698
network.ifr_flags &= ~(short)IFF_UP; /* clear flag */
1700
sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1703
perror_plus("socket");
1709
fprintf_plus(stderr, "Taking down interface \"%s\"\n",
1713
/* Raise priviliges */
1716
ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
1719
/* Lower privileges */
1722
/* Close the socket */
1723
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1725
perror_plus("close");
1728
if(ret_setflags == -1){
1730
perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");
1735
fprintf_plus(stderr, "Interface \"%s\" is already down; odd\n",
824
1743
int main(int argc, char *argv[]){
825
1744
AvahiSServiceBrowser *sb = NULL;
828
1747
intmax_t tmpmax;
830
1749
int exitcode = EXIT_SUCCESS;
831
const char *interface = "eth0";
832
struct ifreq network;
836
char *connect_to = NULL;
1750
char *interfaces = NULL;
1751
size_t interfaces_size = 0;
1752
char *interfaces_to_take_down = NULL;
1753
size_t interfaces_to_take_down_size = 0;
837
1754
char tempdir[] = "/tmp/mandosXXXXXX";
838
1755
bool tempdir_created = false;
839
1756
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
840
1757
const char *seckey = PATHDIR "/" SECKEY;
841
1758
const char *pubkey = PATHDIR "/" PUBKEY;
1759
char *interfaces_hooks = NULL;
1760
size_t interfaces_hooks_size = 0;
843
mandos_context mc = { .simple_poll = NULL, .server = NULL,
844
.dh_bits = 1024, .priority = "SECURE256"
845
":!CTYPE-X.509:+CTYPE-OPENPGP" };
846
1762
bool gnutls_initialized = false;
847
1763
bool gpgme_initialized = false;
1765
double retry_interval = 10; /* 10s between trying a server and
1766
retrying the same server again */
1768
struct sigaction old_sigterm_action = { .sa_handler = SIG_DFL };
1769
struct sigaction sigterm_action = { .sa_handler = handle_sigterm };
1774
/* Lower any group privileges we might have, just to be safe */
1778
perror_plus("setgid");
1781
/* Lower user privileges (temporarily) */
1785
perror_plus("seteuid");
851
1793
struct argp_option options[] = {
915
1879
mc.priority = arg;
917
1881
case 131: /* --delay */
918
ret = sscanf(arg, "%lf%n", &delay, &numchars);
919
if(ret < 1 or arg[numchars] != '\0'){
920
fprintf(stderr, "Bad delay\n");
1883
delay = strtof(arg, &tmp);
1884
if(errno != 0 or tmp == arg or *tmp != '\0'){
1885
argp_error(state, "Bad delay");
1887
case 132: /* --retry */
1889
retry_interval = strtod(arg, &tmp);
1890
if(errno != 0 or tmp == arg or *tmp != '\0'
1891
or (retry_interval * 1000) > INT_MAX
1892
or retry_interval < 0){
1893
argp_error(state, "Bad retry interval");
1896
case 133: /* --network-hook-dir */
1900
* These reproduce what we would get without ARGP_NO_HELP
1902
case '?': /* --help */
1903
argp_state_help(state, state->out_stream,
1904
(ARGP_HELP_STD_HELP | ARGP_HELP_EXIT_ERR)
1905
& ~(unsigned int)ARGP_HELP_EXIT_OK);
1906
case -3: /* --usage */
1907
argp_state_help(state, state->out_stream,
1908
ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);
1909
case 'V': /* --version */
1910
fprintf_plus(state->out_stream, "%s\n", argp_program_version);
1911
exit(argp_err_exit_status);
929
1914
return ARGP_ERR_UNKNOWN;
934
1919
struct argp argp = { .options = options, .parser = parse_opt,
936
1921
.doc = "Mandos client -- Get and decrypt"
937
1922
" passwords from a Mandos server" };
938
ret = argp_parse(&argp, argc, argv, 0, 0, NULL);
939
if(ret == ARGP_ERR_UNKNOWN){
940
fprintf(stderr, "Unknown error while parsing arguments\n");
941
exitcode = EXIT_FAILURE;
946
/* If the interface is down, bring it up */
949
/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO
950
messages to mess up the prompt */
951
ret = klogctl(8, NULL, 5);
957
sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
960
exitcode = EXIT_FAILURE;
962
ret = klogctl(7, NULL, 0);
969
strcpy(network.ifr_name, interface);
970
ret = ioctl(sd, SIOCGIFFLAGS, &network);
972
perror("ioctl SIOCGIFFLAGS");
974
ret = klogctl(7, NULL, 0);
979
exitcode = EXIT_FAILURE;
982
if((network.ifr_flags & IFF_UP) == 0){
983
network.ifr_flags |= IFF_UP;
984
ret = ioctl(sd, SIOCSIFFLAGS, &network);
986
perror("ioctl SIOCSIFFLAGS");
987
exitcode = EXIT_FAILURE;
989
ret = klogctl(7, NULL, 0);
997
/* sleep checking until interface is running */
998
for(int i=0; i < delay * 4; i++){
999
ret = ioctl(sd, SIOCGIFFLAGS, &network);
1001
perror("ioctl SIOCGIFFLAGS");
1002
} else if(network.ifr_flags & IFF_RUNNING){
1005
struct timespec sleeptime = { .tv_nsec = 250000000 };
1006
ret = nanosleep(&sleeptime, NULL);
1007
if(ret == -1 and errno != EINTR){
1008
perror("nanosleep");
1011
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1016
/* Restores kernel loglevel to default */
1017
ret = klogctl(7, NULL, 0);
1037
ret = init_gnutls_global(&mc, pubkey, seckey);
1039
fprintf(stderr, "init_gnutls_global failed\n");
1040
exitcode = EXIT_FAILURE;
1923
ret = argp_parse(&argp, argc, argv,
1924
ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);
1931
perror_plus("argp_parse");
1932
exitcode = EX_OSERR;
1935
exitcode = EX_USAGE;
1941
/* Work around Debian bug #633582:
1942
<http://bugs.debian.org/633582> */
1944
/* Re-raise priviliges */
1945
if(raise_privileges() == 0){
1948
if(strcmp(seckey, PATHDIR "/" SECKEY) == 0){
1949
int seckey_fd = open(seckey, O_RDONLY);
1950
if(seckey_fd == -1){
1951
perror_plus("open");
1953
ret = (int)TEMP_FAILURE_RETRY(fstat(seckey_fd, &st));
1955
perror_plus("fstat");
1957
if(S_ISREG(st.st_mode)
1958
and st.st_uid == 0 and st.st_gid == 0){
1959
ret = fchown(seckey_fd, uid, gid);
1961
perror_plus("fchown");
1965
TEMP_FAILURE_RETRY(close(seckey_fd));
1969
if(strcmp(pubkey, PATHDIR "/" PUBKEY) == 0){
1970
int pubkey_fd = open(pubkey, O_RDONLY);
1971
if(pubkey_fd == -1){
1972
perror_plus("open");
1974
ret = (int)TEMP_FAILURE_RETRY(fstat(pubkey_fd, &st));
1976
perror_plus("fstat");
1978
if(S_ISREG(st.st_mode)
1979
and st.st_uid == 0 and st.st_gid == 0){
1980
ret = fchown(pubkey_fd, uid, gid);
1982
perror_plus("fchown");
1986
TEMP_FAILURE_RETRY(close(pubkey_fd));
1990
/* Lower privileges */
1994
perror_plus("seteuid");
1999
/* Remove empty interface names */
2001
char *interface = NULL;
2002
while((interface = argz_next(interfaces, interfaces_size,
2004
if(if_nametoindex(interface) == 0){
2005
if(interface[0] != '\0' and strcmp(interface, "none") != 0){
2006
fprintf_plus(stderr, "Not using nonexisting interface"
2007
" \"%s\"\n", interface);
2009
argz_delete(&interfaces, &interfaces_size, interface);
2015
/* Run network hooks */
2017
ret_errno = argz_append(&interfaces_hooks, &interfaces_hooks_size,
2018
interfaces, interfaces_size);
2021
perror_plus("argz_append");
2024
argz_stringify(interfaces_hooks, interfaces_hooks_size, (int)',');
2025
if(not run_network_hooks("start", interfaces_hooks, delay)){
2031
avahi_set_log_function(empty_log);
2034
/* Initialize Avahi early so avahi_simple_poll_quit() can be called
2035
from the signal handler */
2036
/* Initialize the pseudo-RNG for Avahi */
2037
srand((unsigned int) time(NULL));
2038
mc.simple_poll = avahi_simple_poll_new();
2039
if(mc.simple_poll == NULL){
2040
fprintf_plus(stderr,
2041
"Avahi: Failed to create simple poll object.\n");
2042
exitcode = EX_UNAVAILABLE;
2046
sigemptyset(&sigterm_action.sa_mask);
2047
ret = sigaddset(&sigterm_action.sa_mask, SIGINT);
2049
perror_plus("sigaddset");
2050
exitcode = EX_OSERR;
2053
ret = sigaddset(&sigterm_action.sa_mask, SIGHUP);
2055
perror_plus("sigaddset");
2056
exitcode = EX_OSERR;
2059
ret = sigaddset(&sigterm_action.sa_mask, SIGTERM);
2061
perror_plus("sigaddset");
2062
exitcode = EX_OSERR;
2065
/* Need to check if the handler is SIG_IGN before handling:
2066
| [[info:libc:Initial Signal Actions]] |
2067
| [[info:libc:Basic Signal Handling]] |
2069
ret = sigaction(SIGINT, NULL, &old_sigterm_action);
2071
perror_plus("sigaction");
2074
if(old_sigterm_action.sa_handler != SIG_IGN){
2075
ret = sigaction(SIGINT, &sigterm_action, NULL);
2077
perror_plus("sigaction");
2078
exitcode = EX_OSERR;
2082
ret = sigaction(SIGHUP, NULL, &old_sigterm_action);
2084
perror_plus("sigaction");
2087
if(old_sigterm_action.sa_handler != SIG_IGN){
2088
ret = sigaction(SIGHUP, &sigterm_action, NULL);
2090
perror_plus("sigaction");
2091
exitcode = EX_OSERR;
2095
ret = sigaction(SIGTERM, NULL, &old_sigterm_action);
2097
perror_plus("sigaction");
2100
if(old_sigterm_action.sa_handler != SIG_IGN){
2101
ret = sigaction(SIGTERM, &sigterm_action, NULL);
2103
perror_plus("sigaction");
2104
exitcode = EX_OSERR;
2109
/* If no interfaces were specified, make a list */
2110
if(interfaces == NULL){
2111
struct dirent **direntries;
2112
/* Look for any good interfaces */
2113
ret = scandir(sys_class_net, &direntries, good_interface,
2116
/* Add all found interfaces to interfaces list */
2117
for(int i = 0; i < ret; ++i){
2118
ret_errno = argz_add(&interfaces, &interfaces_size,
2119
direntries[i]->d_name);
2121
perror_plus("argz_add");
2125
fprintf_plus(stderr, "Will use interface \"%s\"\n",
2126
direntries[i]->d_name);
2132
fprintf_plus(stderr, "Could not find a network interface\n");
2133
exitcode = EXIT_FAILURE;
2138
/* If we only got one interface, explicitly use only that one */
2139
if(argz_count(interfaces, interfaces_size) == 1){
2141
fprintf_plus(stderr, "Using only interface \"%s\"\n",
2144
if_index = (AvahiIfIndex)if_nametoindex(interfaces);
2147
/* Bring up interfaces which are down */
2148
if(not (argz_count(interfaces, interfaces_size) == 1
2149
and strcmp(interfaces, "none") == 0)){
2150
char *interface = NULL;
2151
while((interface = argz_next(interfaces, interfaces_size,
2153
bool interface_was_up = interface_is_up(interface);
2154
ret = bring_up_interface(interface, delay);
2155
if(not interface_was_up){
2158
perror_plus("Failed to bring up interface");
2160
ret_errno = argz_add(&interfaces_to_take_down,
2161
&interfaces_to_take_down_size,
2168
interfaces_size = 0;
2169
if(debug and (interfaces_to_take_down == NULL)){
2170
fprintf_plus(stderr, "No interfaces were brought up\n");
2178
ret = init_gnutls_global(pubkey, seckey);
2180
fprintf_plus(stderr, "init_gnutls_global failed\n");
2181
exitcode = EX_UNAVAILABLE;
1043
2184
gnutls_initialized = true;
1046
2191
if(mkdtemp(tempdir) == NULL){
2192
perror_plus("mkdtemp");
1050
2195
tempdir_created = true;
1052
if(not init_gpgme(&mc, pubkey, seckey, tempdir)){
1053
fprintf(stderr, "init_gpgme failed\n");
1054
exitcode = EXIT_FAILURE;
2201
if(not init_gpgme(pubkey, seckey, tempdir)){
2202
fprintf_plus(stderr, "init_gpgme failed\n");
2203
exitcode = EX_UNAVAILABLE;
1057
2206
gpgme_initialized = true;
1060
if_index = (AvahiIfIndex) if_nametoindex(interface);
1062
fprintf(stderr, "No such interface: \"%s\"\n", interface);
1063
exitcode = EXIT_FAILURE;