71
71
INET_ADDRSTRLEN, INET6_ADDRSTRLEN
73
73
#include <unistd.h> /* close(), SEEK_SET, off_t, write(),
74
getuid(), getgid(), seteuid(),
74
getuid(), getgid(), setuid(),
76
76
#include <arpa/inet.h> /* inet_pton(), htons */
77
77
#include <iso646.h> /* not, or, and */
80
80
argp_parse(), ARGP_KEY_ARG,
81
81
ARGP_KEY_END, ARGP_ERR_UNKNOWN */
82
82
#include <signal.h> /* sigemptyset(), sigaddset(),
83
sigaction(), SIGTERM, sig_atomic_t,
83
sigaction(), SIGTERM, sigaction,
87
87
#include <sys/klog.h> /* klogctl() */
142
142
.dh_bits = 1024, .priority = "SECURE256"
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143
":!CTYPE-X.509:+CTYPE-OPENPGP" };
145
sig_atomic_t quit_now = 0;
146
int signal_received = 0;
149
146
* Make additional room in "buffer" for at least BUFFER_SIZE more
150
147
* bytes. "buffer_capacity" is how much is currently allocated,
313
310
gpgme_recipient_t recipient;
314
311
recipient = result->recipients;
315
while(recipient != NULL){
316
fprintf(stderr, "Public key algorithm: %s\n",
317
gpgme_pubkey_algo_name(recipient->pubkey_algo));
318
fprintf(stderr, "Key ID: %s\n", recipient->keyid);
319
fprintf(stderr, "Secret key available: %s\n",
320
recipient->status == GPG_ERR_NO_SECKEY
322
recipient = recipient->next;
313
while(recipient != NULL){
314
fprintf(stderr, "Public key algorithm: %s\n",
315
gpgme_pubkey_algo_name(recipient->pubkey_algo));
316
fprintf(stderr, "Key ID: %s\n", recipient->keyid);
317
fprintf(stderr, "Secret key available: %s\n",
318
recipient->status == GPG_ERR_NO_SECKEY
320
recipient = recipient->next;
477
476
static int init_gnutls_session(gnutls_session_t *session){
479
478
/* GnuTLS session creation */
481
ret = gnutls_init(session, GNUTLS_SERVER);
485
} while(ret == GNUTLS_E_INTERRUPTED or ret == GNUTLS_E_AGAIN);
479
ret = gnutls_init(session, GNUTLS_SERVER);
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480
if(ret != GNUTLS_E_SUCCESS){
487
481
fprintf(stderr, "Error in GnuTLS session initialization: %s\n",
488
482
safer_gnutls_strerror(ret));
494
ret = gnutls_priority_set_direct(*session, mc.priority, &err);
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gnutls_deinit(*session);
499
} while(ret == GNUTLS_E_INTERRUPTED or ret == GNUTLS_E_AGAIN);
487
ret = gnutls_priority_set_direct(*session, mc.priority, &err);
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488
if(ret != GNUTLS_E_SUCCESS){
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489
fprintf(stderr, "Syntax error at: %s\n", err);
502
490
fprintf(stderr, "GnuTLS error: %s\n",
510
ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,
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gnutls_deinit(*session);
516
} while(ret == GNUTLS_E_INTERRUPTED or ret == GNUTLS_E_AGAIN);
497
ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,
517
499
if(ret != GNUTLS_E_SUCCESS){
518
500
fprintf(stderr, "Error setting GnuTLS credentials: %s\n",
519
501
safer_gnutls_strerror(ret));
524
506
/* ignore client certificate if any. */
525
gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);
507
gnutls_certificate_server_set_request(*session,
527
510
gnutls_dh_set_prime_bits(*session, mc.dh_bits);
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520
static int start_mandos_communication(const char *ip, uint16_t port,
538
521
AvahiIfIndex if_index,
540
int ret, tcp_sd = -1;
543
526
struct sockaddr_in in;
544
527
struct sockaddr_in6 in6;
546
529
char *buffer = NULL;
547
char *decrypted_buffer = NULL;
530
char *decrypted_buffer;
548
531
size_t buffer_length = 0;
549
532
size_t buffer_capacity = 0;
533
ssize_t decrypted_buffer_size;
552
536
gnutls_session_t session;
553
537
int pf; /* Protocol family */
581
561
tcp_sd = socket(pf, SOCK_STREAM, 0);
583
563
perror("socket");
591
567
memset(&to, 0, sizeof(to));
592
568
if(af == AF_INET6){
593
to.in6.sin6_family = (sa_family_t)af;
569
to.in6.sin6_family = (uint16_t)af;
594
570
ret = inet_pton(af, ip, &to.in6.sin6_addr);
595
571
} else { /* IPv4 */
596
572
to.in.sin_family = (sa_family_t)af;
615
591
if(if_index == AVAHI_IF_UNSPEC){
616
592
fprintf(stderr, "An IPv6 link-local address is incomplete"
617
593
" without a network interface\n");
620
596
/* Set the network interface number as scope */
621
597
to.in6.sin6_scope_id = (uint32_t)if_index;
711
672
fprintf(stderr, "Establishing TLS session with %s\n", ip);
718
675
gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);
725
678
ret = gnutls_handshake(session);
729
679
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
731
681
if(ret != GNUTLS_E_SUCCESS){
771
714
case GNUTLS_E_AGAIN:
773
716
case GNUTLS_E_REHANDSHAKE:
775
718
ret = gnutls_handshake(session);
780
719
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
782
721
fprintf(stderr, "*** GnuTLS Re-handshake failed ***\n");
783
722
gnutls_perror(ret);
788
728
fprintf(stderr, "Unknown error while reading data from"
789
729
" encrypted session with Mandos server\n");
790
731
gnutls_bye(session, GNUTLS_SHUT_RDWR);
799
740
fprintf(stderr, "Closing TLS session\n");
807
ret = gnutls_bye(session, GNUTLS_SHUT_RDWR);
811
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
743
gnutls_bye(session, GNUTLS_SHUT_RDWR);
813
745
if(buffer_length > 0){
814
ssize_t decrypted_buffer_size;
815
746
decrypted_buffer_size = pgp_packet_decrypt(buffer,
817
748
&decrypted_buffer);
818
749
if(decrypted_buffer_size >= 0){
821
751
while(written < (size_t) decrypted_buffer_size){
826
752
ret = (int)fwrite(decrypted_buffer + written, 1,
827
753
(size_t)decrypted_buffer_size - written,
880
sig_atomic_t quit_now = 0;
963
882
/* stop main loop after sigterm has been called */
964
static void handle_sigterm(int sig){
883
static void handle_sigterm(__attribute__((unused)) int sig){
969
signal_received = sig;
970
888
int old_errno = errno;
971
889
if(mc.simple_poll != NULL){
972
890
avahi_simple_poll_quit(mc.simple_poll);
998
915
bool gpgme_initialized = false;
999
916
float delay = 2.5f;
1001
struct sigaction old_sigterm_action = { .sa_handler = SIG_DFL };
918
struct sigaction old_sigterm_action;
1002
919
struct sigaction sigterm_action = { .sa_handler = handle_sigterm };
1007
/* Lower any group privileges we might have, just to be safe */
1014
/* Lower user privileges (temporarily) */
1026
922
struct argp_option options[] = {
1027
923
{ .name = "debug", .key = 128,
1154
1050
exitcode = EXIT_FAILURE;
1157
/* Need to check if the handler is SIG_IGN before handling:
1158
| [[info:libc:Initial Signal Actions]] |
1159
| [[info:libc:Basic Signal Handling]] |
1161
ret = sigaction(SIGINT, NULL, &old_sigterm_action);
1163
perror("sigaction");
1164
return EXIT_FAILURE;
1166
if(old_sigterm_action.sa_handler != SIG_IGN){
1167
ret = sigaction(SIGINT, &sigterm_action, NULL);
1169
perror("sigaction");
1170
exitcode = EXIT_FAILURE;
1174
ret = sigaction(SIGHUP, NULL, &old_sigterm_action);
1176
perror("sigaction");
1177
return EXIT_FAILURE;
1179
if(old_sigterm_action.sa_handler != SIG_IGN){
1180
ret = sigaction(SIGHUP, &sigterm_action, NULL);
1182
perror("sigaction");
1183
exitcode = EXIT_FAILURE;
1187
ret = sigaction(SIGTERM, NULL, &old_sigterm_action);
1189
perror("sigaction");
1190
return EXIT_FAILURE;
1192
if(old_sigterm_action.sa_handler != SIG_IGN){
1193
ret = sigaction(SIGTERM, &sigterm_action, NULL);
1195
perror("sigaction");
1196
exitcode = EXIT_FAILURE;
1053
ret = sigaction(SIGTERM, &sigterm_action, &old_sigterm_action);
1055
perror("sigaction");
1056
exitcode = EXIT_FAILURE;
1201
1060
/* If the interface is down, bring it up */
1202
1061
if(interface[0] != '\0'){
1203
if_index = (AvahiIfIndex) if_nametoindex(interface);
1205
fprintf(stderr, "No such interface: \"%s\"\n", interface);
1206
exitcode = EXIT_FAILURE;
1214
/* Re-raise priviliges */
1221
1062
#ifdef __linux__
1222
1063
/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO
1223
1064
messages to mess up the prompt */
1263
1098
#endif /* __linux__ */
1264
1099
exitcode = EXIT_FAILURE;
1265
/* Lower privileges */
1273
1102
if((network.ifr_flags & IFF_UP) == 0){
1274
1103
network.ifr_flags |= IFF_UP;
1275
take_down_interface = true;
1276
1104
ret = ioctl(sd, SIOCSIFFLAGS, &network);
1278
take_down_interface = false;
1279
1106
perror("ioctl SIOCSIFFLAGS");
1280
1107
exitcode = EXIT_FAILURE;
1281
1108
#ifdef __linux__
1355
1168
gnutls_initialized = true;
1362
tempdir_created = true;
1363
1171
if(mkdtemp(tempdir) == NULL){
1364
tempdir_created = false;
1365
1172
perror("mkdtemp");
1175
tempdir_created = true;
1373
1177
if(not init_gpgme(pubkey, seckey, tempdir)){
1374
1178
fprintf(stderr, "init_gpgme failed\n");
1378
1182
gpgme_initialized = true;
1185
if(interface[0] != '\0'){
1186
if_index = (AvahiIfIndex) if_nametoindex(interface);
1188
fprintf(stderr, "No such interface: \"%s\"\n", interface);
1189
exitcode = EXIT_FAILURE;
1385
1194
if(connect_to != NULL){
1471
1257
/* Create the Avahi service browser */
1472
1258
sb = avahi_s_service_browser_new(mc.server, if_index,
1473
1259
AVAHI_PROTO_UNSPEC, "_mandos._tcp",
1517
1299
gpgme_release(mc.ctx);
1520
/* Take down the network interface */
1521
if(take_down_interface){
1522
/* Re-raise priviliges */
1529
ret = ioctl(sd, SIOCGIFFLAGS, &network);
1531
perror("ioctl SIOCGIFFLAGS");
1532
} else if(network.ifr_flags & IFF_UP) {
1533
network.ifr_flags &= ~IFF_UP; /* clear flag */
1534
ret = ioctl(sd, SIOCSIFFLAGS, &network);
1536
perror("ioctl SIOCSIFFLAGS");
1539
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1543
/* Lower privileges permanently */
1552
1302
/* Removes the temp directory used by GPGME */
1553
1303
if(tempdir_created){