71
71
INET_ADDRSTRLEN, INET6_ADDRSTRLEN
73
73
#include <unistd.h> /* close(), SEEK_SET, off_t, write(),
74
getuid(), getgid(), setuid(),
74
getuid(), getgid(), seteuid(),
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, sigaction,
83
sigaction(), SIGTERM, sig_atomic_t,
87
87
#include <sys/klog.h> /* klogctl() */
142
142
.dh_bits = 1024, .priority = "SECURE256"
143
143
":!CTYPE-X.509:+CTYPE-OPENPGP" };
145
sig_atomic_t quit_now = 0;
146
int signal_received = 0;
146
149
* Make additional room in "buffer" for at least BUFFER_SIZE more
147
150
* bytes. "buffer_capacity" is how much is currently allocated,
310
313
gpgme_recipient_t recipient;
311
314
recipient = result->recipients;
313
while(recipient != NULL){
314
fprintf(stderr, "Public key algorithm: %s\n",
315
gpgme_pubkey_algo_name(recipient->pubkey_algo));
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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;
315
while(recipient != NULL){
316
fprintf(stderr, "Public key algorithm: %s\n",
317
gpgme_pubkey_algo_name(recipient->pubkey_algo));
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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;
476
477
static int init_gnutls_session(gnutls_session_t *session){
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479
/* GnuTLS session creation */
479
ret = gnutls_init(session, GNUTLS_SERVER);
481
ret = gnutls_init(session, GNUTLS_SERVER);
485
} while(ret == GNUTLS_E_INTERRUPTED or ret == GNUTLS_E_AGAIN);
480
486
if(ret != GNUTLS_E_SUCCESS){
481
487
fprintf(stderr, "Error in GnuTLS session initialization: %s\n",
482
488
safer_gnutls_strerror(ret));
487
ret = gnutls_priority_set_direct(*session, mc.priority, &err);
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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);
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500
if(ret != GNUTLS_E_SUCCESS){
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501
fprintf(stderr, "Syntax error at: %s\n", err);
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502
fprintf(stderr, "GnuTLS error: %s\n",
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ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,
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);
499
517
if(ret != GNUTLS_E_SUCCESS){
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518
fprintf(stderr, "Error setting GnuTLS credentials: %s\n",
501
519
safer_gnutls_strerror(ret));
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524
/* ignore client certificate if any. */
507
gnutls_certificate_server_set_request(*session,
525
gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);
510
527
gnutls_dh_set_prime_bits(*session, mc.dh_bits);
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537
static int start_mandos_communication(const char *ip, uint16_t port,
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538
AvahiIfIndex if_index,
540
int ret, tcp_sd = -1;
526
543
struct sockaddr_in in;
527
544
struct sockaddr_in6 in6;
529
546
char *buffer = NULL;
530
char *decrypted_buffer;
547
char *decrypted_buffer = NULL;
531
548
size_t buffer_length = 0;
532
549
size_t buffer_capacity = 0;
533
ssize_t decrypted_buffer_size;
536
552
gnutls_session_t session;
537
553
int pf; /* Protocol family */
561
581
tcp_sd = socket(pf, SOCK_STREAM, 0);
563
583
perror("socket");
567
591
memset(&to, 0, sizeof(to));
568
592
if(af == AF_INET6){
569
to.in6.sin6_family = (uint16_t)af;
593
to.in6.sin6_family = (sa_family_t)af;
570
594
ret = inet_pton(af, ip, &to.in6.sin6_addr);
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595
} else { /* IPv4 */
572
596
to.in.sin_family = (sa_family_t)af;
591
615
if(if_index == AVAHI_IF_UNSPEC){
592
616
fprintf(stderr, "An IPv6 link-local address is incomplete"
593
617
" without a network interface\n");
596
620
/* Set the network interface number as scope */
597
621
to.in6.sin6_scope_id = (uint32_t)if_index;
672
711
fprintf(stderr, "Establishing TLS session with %s\n", ip);
675
718
gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);
678
725
ret = gnutls_handshake(session);
679
729
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
681
731
if(ret != GNUTLS_E_SUCCESS){
714
771
case GNUTLS_E_AGAIN:
716
773
case GNUTLS_E_REHANDSHAKE:
718
775
ret = gnutls_handshake(session);
719
780
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
721
782
fprintf(stderr, "*** GnuTLS Re-handshake failed ***\n");
722
783
gnutls_perror(ret);
728
788
fprintf(stderr, "Unknown error while reading data from"
729
789
" encrypted session with Mandos server\n");
731
790
gnutls_bye(session, GNUTLS_SHUT_RDWR);
740
799
fprintf(stderr, "Closing TLS session\n");
743
gnutls_bye(session, GNUTLS_SHUT_RDWR);
807
ret = gnutls_bye(session, GNUTLS_SHUT_RDWR);
811
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
745
813
if(buffer_length > 0){
814
ssize_t decrypted_buffer_size;
746
815
decrypted_buffer_size = pgp_packet_decrypt(buffer,
748
817
&decrypted_buffer);
749
818
if(decrypted_buffer_size >= 0){
751
821
while(written < (size_t) decrypted_buffer_size){
752
826
ret = (int)fwrite(decrypted_buffer + written, 1,
753
827
(size_t)decrypted_buffer_size - written,
880
sig_atomic_t quit_now = 0;
882
963
/* stop main loop after sigterm has been called */
883
static void handle_sigterm(__attribute__((unused)) int sig){
964
static void handle_sigterm(int sig){
969
signal_received = sig;
888
970
int old_errno = errno;
889
971
if(mc.simple_poll != NULL){
890
972
avahi_simple_poll_quit(mc.simple_poll);
915
998
bool gpgme_initialized = false;
916
999
float delay = 2.5f;
918
struct sigaction old_sigterm_action;
1001
struct sigaction old_sigterm_action = { .sa_handler = SIG_DFL };
919
1002
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) */
922
1026
struct argp_option options[] = {
923
1027
{ .name = "debug", .key = 128,
1050
1154
exitcode = EXIT_FAILURE;
1053
ret = sigaction(SIGTERM, &sigterm_action, &old_sigterm_action);
1055
perror("sigaction");
1056
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;
1060
1201
/* If the interface is down, bring it up */
1061
1202
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 */
1062
1221
#ifdef __linux__
1063
1222
/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO
1064
1223
messages to mess up the prompt */
1098
1263
#endif /* __linux__ */
1099
1264
exitcode = EXIT_FAILURE;
1265
/* Lower privileges */
1102
1273
if((network.ifr_flags & IFF_UP) == 0){
1103
1274
network.ifr_flags |= IFF_UP;
1275
take_down_interface = true;
1104
1276
ret = ioctl(sd, SIOCSIFFLAGS, &network);
1278
take_down_interface = false;
1106
1279
perror("ioctl SIOCSIFFLAGS");
1107
1280
exitcode = EXIT_FAILURE;
1108
1281
#ifdef __linux__
1168
1355
gnutls_initialized = true;
1362
tempdir_created = true;
1171
1363
if(mkdtemp(tempdir) == NULL){
1364
tempdir_created = false;
1172
1365
perror("mkdtemp");
1175
tempdir_created = true;
1177
1373
if(not init_gpgme(pubkey, seckey, tempdir)){
1178
1374
fprintf(stderr, "init_gpgme failed\n");
1182
1378
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;
1194
1385
if(connect_to != NULL){
1257
1471
/* Create the Avahi service browser */
1258
1472
sb = avahi_s_service_browser_new(mc.server, if_index,
1259
1473
AVAHI_PROTO_UNSPEC, "_mandos._tcp",
1299
1517
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 */
1302
1552
/* Removes the temp directory used by GPGME */
1303
1553
if(tempdir_created){