49
47
#include <sys/types.h> /* socket(), inet_pton(), sockaddr,
50
48
sockaddr_in6, PF_INET6,
51
49
SOCK_STREAM, INET6_ADDRSTRLEN,
52
uid_t, gid_t, open(), opendir(),
54
#include <sys/stat.h> /* open() */
51
#include <inttypes.h> /* PRIu16 */
55
52
#include <sys/socket.h> /* socket(), struct sockaddr_in6,
56
53
struct in6_addr, inet_pton(),
58
#include <fcntl.h> /* open() */
59
#include <dirent.h> /* opendir(), struct dirent, readdir()
61
#include <inttypes.h> /* PRIu16, intmax_t, SCNdMAX */
62
55
#include <assert.h> /* assert() */
63
56
#include <errno.h> /* perror(), errno */
64
57
#include <time.h> /* time() */
65
58
#include <net/if.h> /* ioctl, ifreq, SIOCGIFFLAGS, IFF_UP,
66
59
SIOCSIFFLAGS, if_indextoname(),
67
60
if_nametoindex(), IF_NAMESIZE */
68
#include <netinet/in.h>
69
61
#include <unistd.h> /* close(), SEEK_SET, off_t, write(),
70
62
getuid(), getgid(), setuid(),
64
#include <netinet/in.h>
72
65
#include <arpa/inet.h> /* inet_pton(), htons */
73
#include <iso646.h> /* not, and, or */
66
#include <iso646.h> /* not, and */
74
67
#include <argp.h> /* struct argp_option, error_t, struct
75
68
argp_state, struct argp,
76
69
argp_parse(), ARGP_KEY_ARG,
135
* Decrypt OpenPGP data using keyrings in HOMEDIR.
136
* Returns -1 on error
149
static bool init_gpgme(mandos_context *mc, const char *seckey,
150
const char *pubkey, const char *tempdir){
138
static ssize_t pgp_packet_decrypt (const char *cryptotext,
141
const char *homedir){
142
gpgme_data_t dh_crypto, dh_plain;
152
144
gpgme_error_t rc;
146
size_t plaintext_capacity = 0;
147
ssize_t plaintext_length = 0;
153
148
gpgme_engine_info_t engine_info;
157
* Helper function to insert pub and seckey to the engine keyring.
159
bool import_key(const char *filename){
161
gpgme_data_t pgp_data;
163
fd = (int)TEMP_FAILURE_RETRY(open(filename, O_RDONLY));
169
rc = gpgme_data_new_from_fd(&pgp_data, fd);
170
if(rc != GPG_ERR_NO_ERROR){
171
fprintf(stderr, "bad gpgme_data_new_from_fd: %s: %s\n",
172
gpgme_strsource(rc), gpgme_strerror(rc));
176
rc = gpgme_op_import(mc->ctx, pgp_data);
177
if(rc != GPG_ERR_NO_ERROR){
178
fprintf(stderr, "bad gpgme_op_import: %s: %s\n",
179
gpgme_strsource(rc), gpgme_strerror(rc));
183
ret = (int)TEMP_FAILURE_RETRY(close(fd));
187
gpgme_data_release(pgp_data);
192
fprintf(stderr, "Initialize gpgme\n");
151
fprintf(stderr, "Trying to decrypt OpenPGP data\n");
196
155
gpgme_check_version(NULL);
197
156
rc = gpgme_engine_check_version(GPGME_PROTOCOL_OpenPGP);
198
if(rc != GPG_ERR_NO_ERROR){
157
if (rc != GPG_ERR_NO_ERROR){
199
158
fprintf(stderr, "bad gpgme_engine_check_version: %s: %s\n",
200
159
gpgme_strsource(rc), gpgme_strerror(rc));
204
/* Set GPGME home directory for the OpenPGP engine only */
205
rc = gpgme_get_engine_info(&engine_info);
206
if(rc != GPG_ERR_NO_ERROR){
163
/* Set GPGME home directory for the OpenPGP engine only */
164
rc = gpgme_get_engine_info (&engine_info);
165
if (rc != GPG_ERR_NO_ERROR){
207
166
fprintf(stderr, "bad gpgme_get_engine_info: %s: %s\n",
208
167
gpgme_strsource(rc), gpgme_strerror(rc));
211
170
while(engine_info != NULL){
212
171
if(engine_info->protocol == GPGME_PROTOCOL_OpenPGP){
213
172
gpgme_set_engine_info(GPGME_PROTOCOL_OpenPGP,
214
engine_info->file_name, tempdir);
173
engine_info->file_name, homedir);
217
176
engine_info = engine_info->next;
219
178
if(engine_info == NULL){
220
fprintf(stderr, "Could not set GPGME home dir to %s\n", tempdir);
224
/* Create new GPGME "context" */
225
rc = gpgme_new(&(mc->ctx));
226
if(rc != GPG_ERR_NO_ERROR){
227
fprintf(stderr, "bad gpgme_new: %s: %s\n",
228
gpgme_strsource(rc), gpgme_strerror(rc));
232
if(not import_key(pubkey) or not import_key(seckey)){
240
* Decrypt OpenPGP data.
241
* Returns -1 on error
243
static ssize_t pgp_packet_decrypt(const mandos_context *mc,
244
const char *cryptotext,
247
gpgme_data_t dh_crypto, dh_plain;
250
size_t plaintext_capacity = 0;
251
ssize_t plaintext_length = 0;
254
fprintf(stderr, "Trying to decrypt OpenPGP data\n");
179
fprintf(stderr, "Could not set GPGME home dir to %s\n", homedir);
257
183
/* Create new GPGME data buffer from memory cryptotext */
258
184
rc = gpgme_data_new_from_mem(&dh_crypto, cryptotext, crypto_size,
260
if(rc != GPG_ERR_NO_ERROR){
186
if (rc != GPG_ERR_NO_ERROR){
261
187
fprintf(stderr, "bad gpgme_data_new_from_mem: %s: %s\n",
262
188
gpgme_strsource(rc), gpgme_strerror(rc));
266
192
/* Create new empty GPGME data buffer for the plaintext */
267
193
rc = gpgme_data_new(&dh_plain);
268
if(rc != GPG_ERR_NO_ERROR){
194
if (rc != GPG_ERR_NO_ERROR){
269
195
fprintf(stderr, "bad gpgme_data_new: %s: %s\n",
270
196
gpgme_strsource(rc), gpgme_strerror(rc));
271
197
gpgme_data_release(dh_crypto);
201
/* Create new GPGME "context" */
202
rc = gpgme_new(&ctx);
203
if (rc != GPG_ERR_NO_ERROR){
204
fprintf(stderr, "bad gpgme_new: %s: %s\n",
205
gpgme_strsource(rc), gpgme_strerror(rc));
206
plaintext_length = -1;
275
210
/* Decrypt data from the cryptotext data buffer to the plaintext
277
rc = gpgme_op_decrypt(mc->ctx, dh_crypto, dh_plain);
278
if(rc != GPG_ERR_NO_ERROR){
212
rc = gpgme_op_decrypt(ctx, dh_crypto, dh_plain);
213
if (rc != GPG_ERR_NO_ERROR){
279
214
fprintf(stderr, "bad gpgme_op_decrypt: %s: %s\n",
280
215
gpgme_strsource(rc), gpgme_strerror(rc));
281
216
plaintext_length = -1;
283
gpgme_decrypt_result_t result;
284
result = gpgme_op_decrypt_result(mc->ctx);
286
fprintf(stderr, "gpgme_op_decrypt_result failed\n");
288
fprintf(stderr, "Unsupported algorithm: %s\n",
289
result->unsupported_algorithm);
290
fprintf(stderr, "Wrong key usage: %u\n",
291
result->wrong_key_usage);
292
if(result->file_name != NULL){
293
fprintf(stderr, "File name: %s\n", result->file_name);
295
gpgme_recipient_t recipient;
296
recipient = result->recipients;
298
while(recipient != NULL){
299
fprintf(stderr, "Public key algorithm: %s\n",
300
gpgme_pubkey_algo_name(recipient->pubkey_algo));
301
fprintf(stderr, "Key ID: %s\n", recipient->keyid);
302
fprintf(stderr, "Secret key available: %s\n",
303
recipient->status == GPG_ERR_NO_SECKEY
305
recipient = recipient->next;
310
217
goto decrypt_end;
314
221
fprintf(stderr, "Decryption of OpenPGP data succeeded\n");
225
gpgme_decrypt_result_t result;
226
result = gpgme_op_decrypt_result(ctx);
228
fprintf(stderr, "gpgme_op_decrypt_result failed\n");
230
fprintf(stderr, "Unsupported algorithm: %s\n",
231
result->unsupported_algorithm);
232
fprintf(stderr, "Wrong key usage: %u\n",
233
result->wrong_key_usage);
234
if(result->file_name != NULL){
235
fprintf(stderr, "File name: %s\n", result->file_name);
237
gpgme_recipient_t recipient;
238
recipient = result->recipients;
240
while(recipient != NULL){
241
fprintf(stderr, "Public key algorithm: %s\n",
242
gpgme_pubkey_algo_name(recipient->pubkey_algo));
243
fprintf(stderr, "Key ID: %s\n", recipient->keyid);
244
fprintf(stderr, "Secret key available: %s\n",
245
recipient->status == GPG_ERR_NO_SECKEY
247
recipient = recipient->next;
317
253
/* Seek back to the beginning of the GPGME plaintext data buffer */
318
if(gpgme_data_seek(dh_plain, (off_t)0, SEEK_SET) == -1){
319
perror("gpgme_data_seek");
254
if (gpgme_data_seek(dh_plain, (off_t) 0, SEEK_SET) == -1){
255
perror("pgpme_data_seek");
320
256
plaintext_length = -1;
321
257
goto decrypt_end;
406
341
/* OpenPGP credentials */
407
342
gnutls_certificate_allocate_credentials(&mc->cred);
408
if(ret != GNUTLS_E_SUCCESS){
409
fprintf(stderr, "GnuTLS memory error: %s\n", /* Spurious warning
413
safer_gnutls_strerror(ret));
414
gnutls_global_deinit();
343
if (ret != GNUTLS_E_SUCCESS){
344
fprintf (stderr, "GnuTLS memory error: %s\n",
345
safer_gnutls_strerror(ret));
346
gnutls_global_deinit ();
419
fprintf(stderr, "Attempting to use OpenPGP public key %s and"
420
" secret key %s as GnuTLS credentials\n", pubkeyfilename,
351
fprintf(stderr, "Attempting to use OpenPGP certificate %s"
352
" and keyfile %s as GnuTLS credentials\n", pubkeyfilename,
424
356
ret = gnutls_certificate_set_openpgp_key_file
425
357
(mc->cred, pubkeyfilename, seckeyfilename,
426
358
GNUTLS_OPENPGP_FMT_BASE64);
427
if(ret != GNUTLS_E_SUCCESS) {
359
if (ret != GNUTLS_E_SUCCESS) {
429
361
"Error[%d] while reading the OpenPGP key pair ('%s',"
430
362
" '%s')\n", ret, pubkeyfilename, seckeyfilename);
431
fprintf(stderr, "The GnuTLS error is: %s\n",
363
fprintf(stdout, "The GnuTLS error is: %s\n",
432
364
safer_gnutls_strerror(ret));
436
368
/* GnuTLS server initialization */
437
369
ret = gnutls_dh_params_init(&mc->dh_params);
438
if(ret != GNUTLS_E_SUCCESS) {
439
fprintf(stderr, "Error in GnuTLS DH parameter initialization:"
440
" %s\n", safer_gnutls_strerror(ret));
370
if (ret != GNUTLS_E_SUCCESS) {
371
fprintf (stderr, "Error in GnuTLS DH parameter initialization:"
372
" %s\n", safer_gnutls_strerror(ret));
443
375
ret = gnutls_dh_params_generate2(mc->dh_params, mc->dh_bits);
444
if(ret != GNUTLS_E_SUCCESS) {
445
fprintf(stderr, "Error in GnuTLS prime generation: %s\n",
446
safer_gnutls_strerror(ret));
376
if (ret != GNUTLS_E_SUCCESS) {
377
fprintf (stderr, "Error in GnuTLS prime generation: %s\n",
378
safer_gnutls_strerror(ret));
450
382
gnutls_certificate_set_dh_params(mc->cred, mc->dh_params);
456
388
gnutls_certificate_free_credentials(mc->cred);
457
389
gnutls_global_deinit();
458
gnutls_dh_params_deinit(mc->dh_params);
462
394
static int init_gnutls_session(mandos_context *mc,
474
406
ret = gnutls_priority_set_direct(*session, mc->priority, &err);
475
if(ret != GNUTLS_E_SUCCESS) {
407
if (ret != GNUTLS_E_SUCCESS) {
476
408
fprintf(stderr, "Syntax error at: %s\n", err);
477
409
fprintf(stderr, "GnuTLS error: %s\n",
478
410
safer_gnutls_strerror(ret));
479
gnutls_deinit(*session);
411
gnutls_deinit (*session);
484
416
ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,
486
if(ret != GNUTLS_E_SUCCESS) {
418
if (ret != GNUTLS_E_SUCCESS) {
487
419
fprintf(stderr, "Error setting GnuTLS credentials: %s\n",
488
420
safer_gnutls_strerror(ret));
489
gnutls_deinit(*session);
421
gnutls_deinit (*session);
493
425
/* ignore client certificate if any. */
494
gnutls_certificate_server_set_request(*session,
426
gnutls_certificate_server_set_request (*session,
497
gnutls_dh_set_prime_bits(*session, mc->dh_bits);
429
gnutls_dh_set_prime_bits (*session, mc->dh_bits);
632
561
fprintf(stderr, "Retrieving pgp encrypted password from %s\n",
637
566
buffer_capacity = adjustbuffer(&buffer, buffer_length,
638
567
buffer_capacity);
639
if(buffer_capacity == 0){
568
if (buffer_capacity == 0){
640
569
perror("adjustbuffer");
645
sret = gnutls_record_recv(session, buffer+buffer_length,
574
ret = gnutls_record_recv(session, buffer+buffer_length,
652
581
case GNUTLS_E_INTERRUPTED:
653
582
case GNUTLS_E_AGAIN:
655
584
case GNUTLS_E_REHANDSHAKE:
657
ret = gnutls_handshake(session);
586
ret = gnutls_handshake (session);
658
587
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
660
589
fprintf(stderr, "*** GnuTLS Re-handshake failed ***\n");
679
608
fprintf(stderr, "Closing TLS session\n");
682
gnutls_bye(session, GNUTLS_SHUT_RDWR);
611
gnutls_bye (session, GNUTLS_SHUT_RDWR);
684
if(buffer_length > 0){
685
decrypted_buffer_size = pgp_packet_decrypt(mc, buffer,
613
if (buffer_length > 0){
614
decrypted_buffer_size = pgp_packet_decrypt(buffer,
688
if(decrypted_buffer_size >= 0){
618
if (decrypted_buffer_size >= 0){
690
620
while(written < (size_t) decrypted_buffer_size){
691
ret = (int)fwrite(decrypted_buffer + written, 1,
692
(size_t)decrypted_buffer_size - written,
621
ret = (int)fwrite (decrypted_buffer + written, 1,
622
(size_t)decrypted_buffer_size - written,
694
624
if(ret == 0 and ferror(stdout)){
696
626
fprintf(stderr, "Error writing encrypted data: %s\n",
755
680
avahi_address_snprint(ip, sizeof(ip), address);
757
682
fprintf(stderr, "Mandos server \"%s\" found on %s (%s, %"
758
PRIdMAX ") on port %" PRIu16 "\n", name, host_name,
759
ip, (intmax_t)interface, port);
683
PRIu16 ") on port %d\n", name, host_name, ip,
761
686
int ret = start_mandos_communication(ip, port, interface, mc);
763
688
avahi_simple_poll_quit(mc->simple_poll);
833
768
char *connect_to = NULL;
834
char tempdir[] = "/tmp/mandosXXXXXX";
835
bool tempdir_created = false;
836
769
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
837
const char *seckey = PATHDIR "/" SECKEY;
838
const char *pubkey = PATHDIR "/" PUBKEY;
770
char *pubkeyfilename = NULL;
771
char *seckeyfilename = NULL;
772
const char *pubkeyname = "pubkey.txt";
773
const char *seckeyname = "seckey.txt";
840
774
mandos_context mc = { .simple_poll = NULL, .server = NULL,
841
.dh_bits = 1024, .priority = "SECURE256"
842
":!CTYPE-X.509:+CTYPE-OPENPGP" };
843
bool gnutls_initialized = false;
844
bool gpgme_initialized = false;
775
.dh_bits = 1024, .priority = "SECURE256"};
776
bool gnutls_initalized = false;
847
779
struct argp_option options[] = {
848
780
{ .name = "debug", .key = 128,
849
781
.doc = "Debug mode", .group = 3 },
850
782
{ .name = "connect", .key = 'c',
851
.arg = "ADDRESS:PORT",
852
.doc = "Connect directly to a specific Mandos server",
784
.doc = "Connect directly to a sepcified mandos server",
854
786
{ .name = "interface", .key = 'i',
856
.doc = "Interface that will be used to search for Mandos"
788
.doc = "Interface that Avahi will conntect through",
790
{ .name = "keydir", .key = 'd',
792
.doc = "Directory where the openpgp keyring is",
859
794
{ .name = "seckey", .key = 's',
861
.doc = "OpenPGP secret key file base name",
796
.doc = "Secret openpgp key for gnutls authentication",
863
798
{ .name = "pubkey", .key = 'p',
865
.doc = "OpenPGP public key file base name",
800
.doc = "Public openpgp key for gnutls authentication",
867
802
{ .name = "dh-bits", .key = 129,
869
.doc = "Bit length of the prime number used in the"
870
" Diffie-Hellman key exchange",
804
.doc = "dh-bits to use in gnutls communication",
872
806
{ .name = "priority", .key = 130,
874
.doc = "GnuTLS priority string for the TLS handshake",
808
.doc = "GNUTLS priority", .group = 1 },
879
error_t parse_opt(int key, char *arg,
880
struct argp_state *state) {
882
case 128: /* --debug */
813
error_t parse_opt (int key, char *arg,
814
struct argp_state *state) {
815
/* Get the INPUT argument from `argp_parse', which we know is
816
a pointer to our plugin list pointer. */
885
case 'c': /* --connect */
886
822
connect_to = arg;
888
case 'i': /* --interface */
891
case 's': /* --seckey */
894
case 'p': /* --pubkey */
897
case 129: /* --dh-bits */
898
ret = sscanf(arg, "%" SCNdMAX "%n", &tmpmax, &numchars);
899
if(ret < 1 or tmpmax != (typeof(mc.dh_bits))tmpmax
900
or arg[numchars] != '\0'){
901
fprintf(stderr, "Bad number of DH bits\n");
838
mc.dh_bits = (unsigned int) strtol(arg, NULL, 10);
902
841
exit(EXIT_FAILURE);
904
mc.dh_bits = (typeof(mc.dh_bits))tmpmax;
906
case 130: /* --priority */
907
845
mc.priority = arg;
909
847
case ARGP_KEY_ARG:
911
849
case ARGP_KEY_END:
919
857
struct argp argp = { .options = options, .parser = parse_opt,
921
859
.doc = "Mandos client -- Get and decrypt"
922
" passwords from a Mandos server" };
923
ret = argp_parse(&argp, argc, argv, 0, 0, NULL);
924
if(ret == ARGP_ERR_UNKNOWN){
860
" passwords from mandos server" };
861
ret = argp_parse (&argp, argc, argv, 0, 0, NULL);
862
if (ret == ARGP_ERR_UNKNOWN){
925
863
fprintf(stderr, "Unknown error while parsing arguments\n");
926
864
exitcode = EXIT_FAILURE;
869
pubkeyfilename = combinepath(keydir, pubkeyname);
870
if (pubkeyfilename == NULL){
871
perror("combinepath");
872
exitcode = EXIT_FAILURE;
876
seckeyfilename = combinepath(keydir, seckeyname);
877
if (seckeyfilename == NULL){
878
perror("combinepath");
879
exitcode = EXIT_FAILURE;
883
ret = init_gnutls_global(&mc, pubkeyfilename, seckeyfilename);
885
fprintf(stderr, "init_gnutls_global failed\n");
886
exitcode = EXIT_FAILURE;
889
gnutls_initalized = true;
931
892
/* If the interface is down, bring it up */
955
ret = (int)TEMP_FAILURE_RETRY(close(sd));
966
929
perror("setgid");
974
ret = init_gnutls_global(&mc, pubkey, seckey);
976
fprintf(stderr, "init_gnutls_global failed\n");
977
exitcode = EXIT_FAILURE;
980
gnutls_initialized = true;
983
if(mkdtemp(tempdir) == NULL){
987
tempdir_created = true;
989
if(not init_gpgme(&mc, pubkey, seckey, tempdir)){
990
fprintf(stderr, "init_gpgme failed\n");
991
exitcode = EXIT_FAILURE;
994
gpgme_initialized = true;
997
932
if_index = (AvahiIfIndex) if_nametoindex(interface);
998
933
if(if_index == 0){
999
934
fprintf(stderr, "No such interface: \"%s\"\n", interface);
1000
exitcode = EXIT_FAILURE;
1004
938
if(connect_to != NULL){
1087
1019
/* Run the main loop */
1090
1022
fprintf(stderr, "Starting Avahi loop search\n");
1093
1025
avahi_simple_poll_loop(mc.simple_poll);
1098
1030
fprintf(stderr, "%s exiting\n", argv[0]);
1101
1033
/* Cleanup things */
1103
1035
avahi_s_service_browser_free(sb);
1105
if(mc.server != NULL)
1037
if (mc.server != NULL)
1106
1038
avahi_server_free(mc.server);
1108
if(mc.simple_poll != NULL)
1040
if (mc.simple_poll != NULL)
1109
1041
avahi_simple_poll_free(mc.simple_poll);
1111
if(gnutls_initialized){
1042
free(pubkeyfilename);
1043
free(seckeyfilename);
1045
if (gnutls_initalized){
1112
1046
gnutls_certificate_free_credentials(mc.cred);
1113
gnutls_global_deinit();
1114
gnutls_dh_params_deinit(mc.dh_params);
1117
if(gpgme_initialized){
1118
gpgme_release(mc.ctx);
1121
/* Removes the temp directory used by GPGME */
1122
if(tempdir_created){
1124
struct dirent *direntry;
1125
d = opendir(tempdir);
1127
if(errno != ENOENT){
1132
direntry = readdir(d);
1133
if(direntry == NULL){
1136
/* Skip "." and ".." */
1137
if(direntry->d_name[0] == '.'
1138
and (direntry->d_name[1] == '\0'
1139
or (direntry->d_name[1] == '.'
1140
and direntry->d_name[2] == '\0'))){
1143
char *fullname = NULL;
1144
ret = asprintf(&fullname, "%s/%s", tempdir,
1150
ret = remove(fullname);
1152
fprintf(stderr, "remove(\"%s\"): %s\n", fullname,
1159
ret = rmdir(tempdir);
1160
if(ret == -1 and errno != ENOENT){
1047
gnutls_global_deinit ();
1165
1050
return exitcode;