120
133
#define PATHDIR "/conf/conf.d/mandos"
121
134
#define SECKEY "seckey.txt"
122
135
#define PUBKEY "pubkey.txt"
136
#define HOOKDIR "/lib/mandos/network-hooks.d"
124
138
bool debug = false;
125
139
static const char mandos_protocol_version[] = "1";
126
140
const char *argp_program_version = "mandos-client " VERSION;
127
const char *argp_program_bug_address = "<mandos@fukt.bsnet.se>";
141
const char *argp_program_bug_address = "<mandos@recompile.se>";
142
static const char sys_class_net[] = "/sys/class/net";
143
char *connect_to = NULL;
144
const char *hookdir = HOOKDIR;
149
/* Doubly linked list that need to be circularly linked when used */
150
typedef struct server{
153
AvahiIfIndex if_index;
155
struct timespec last_seen;
129
160
/* Used for passing in values through the Avahi callback functions */
131
AvahiSimplePoll *simple_poll;
132
162
AvahiServer *server;
133
163
gnutls_certificate_credentials_t cred;
134
164
unsigned int dh_bits;
135
165
gnutls_dh_params_t dh_params;
136
166
const char *priority;
168
server *current_server;
170
size_t interfaces_size;
138
171
} mandos_context;
140
/* global context so signal handler can reach it*/
141
mandos_context mc = { .simple_poll = NULL, .server = NULL,
142
.dh_bits = 1024, .priority = "SECURE256"
143
":!CTYPE-X.509:+CTYPE-OPENPGP" };
173
/* global so signal handler can reach it*/
174
AvahiSimplePoll *simple_poll;
176
sig_atomic_t quit_now = 0;
177
int signal_received = 0;
179
/* Function to use when printing errors */
180
void perror_plus(const char *print_text){
182
fprintf(stderr, "Mandos plugin %s: ",
183
program_invocation_short_name);
188
__attribute__((format (gnu_printf, 2, 3), nonnull))
189
int fprintf_plus(FILE *stream, const char *format, ...){
191
va_start (ap, format);
193
TEMP_FAILURE_RETRY(fprintf(stream, "Mandos plugin %s: ",
194
program_invocation_short_name));
195
return (int)TEMP_FAILURE_RETRY(vfprintf(stream, format, ap));
146
199
* Make additional room in "buffer" for at least BUFFER_SIZE more
147
200
* bytes. "buffer_capacity" is how much is currently allocated,
148
201
* "buffer_length" is how much is already used.
203
__attribute__((nonnull, warn_unused_result))
150
204
size_t incbuffer(char **buffer, size_t buffer_length,
151
size_t buffer_capacity){
205
size_t buffer_capacity){
152
206
if(buffer_length + BUFFER_SIZE > buffer_capacity){
153
*buffer = realloc(*buffer, buffer_capacity + BUFFER_SIZE);
207
char *new_buf = realloc(*buffer, buffer_capacity + BUFFER_SIZE);
209
int old_errno = errno;
157
216
buffer_capacity += BUFFER_SIZE;
159
218
return buffer_capacity;
221
/* Add server to set of servers to retry periodically */
222
__attribute__((nonnull, warn_unused_result))
223
bool add_server(const char *ip, in_port_t port, AvahiIfIndex if_index,
224
int af, server **current_server){
226
server *new_server = malloc(sizeof(server));
227
if(new_server == NULL){
228
perror_plus("malloc");
231
*new_server = (server){ .ip = strdup(ip),
233
.if_index = if_index,
235
if(new_server->ip == NULL){
236
perror_plus("strdup");
240
ret = clock_gettime(CLOCK_MONOTONIC, &(new_server->last_seen));
242
perror_plus("clock_gettime");
244
#pragma GCC diagnostic push
245
#pragma GCC diagnostic ignored "-Wcast-qual"
247
free((char *)(new_server->ip));
249
#pragma GCC diagnostic pop
254
/* Special case of first server */
255
if(*current_server == NULL){
256
new_server->next = new_server;
257
new_server->prev = new_server;
258
*current_server = new_server;
260
/* Place the new server last in the list */
261
new_server->next = *current_server;
262
new_server->prev = (*current_server)->prev;
263
new_server->prev->next = new_server;
264
(*current_server)->prev = new_server;
163
270
* Initialize GPGME.
165
static bool init_gpgme(const char *seckey,
166
const char *pubkey, const char *tempdir){
272
__attribute__((nonnull, warn_unused_result))
273
static bool init_gpgme(const char * const seckey,
274
const char * const pubkey,
275
const char * const tempdir,
168
277
gpgme_error_t rc;
169
278
gpgme_engine_info_t engine_info;
173
281
* Helper function to insert pub and seckey to the engine keyring.
175
bool import_key(const char *filename){
283
bool import_key(const char * const filename){
177
286
gpgme_data_t pgp_data;
179
288
fd = (int)TEMP_FAILURE_RETRY(open(filename, O_RDONLY));
185
294
rc = gpgme_data_new_from_fd(&pgp_data, fd);
186
295
if(rc != GPG_ERR_NO_ERROR){
187
fprintf(stderr, "bad gpgme_data_new_from_fd: %s: %s\n",
188
gpgme_strsource(rc), gpgme_strerror(rc));
296
fprintf_plus(stderr, "bad gpgme_data_new_from_fd: %s: %s\n",
297
gpgme_strsource(rc), gpgme_strerror(rc));
192
rc = gpgme_op_import(mc.ctx, pgp_data);
301
rc = gpgme_op_import(mc->ctx, pgp_data);
193
302
if(rc != GPG_ERR_NO_ERROR){
194
fprintf(stderr, "bad gpgme_op_import: %s: %s\n",
195
gpgme_strsource(rc), gpgme_strerror(rc));
303
fprintf_plus(stderr, "bad gpgme_op_import: %s: %s\n",
304
gpgme_strsource(rc), gpgme_strerror(rc));
199
308
ret = (int)TEMP_FAILURE_RETRY(close(fd));
310
perror_plus("close");
203
312
gpgme_data_release(pgp_data);
208
fprintf(stderr, "Initializing GPGME\n");
317
fprintf_plus(stderr, "Initializing GPGME\n");
212
321
gpgme_check_version(NULL);
213
322
rc = gpgme_engine_check_version(GPGME_PROTOCOL_OpenPGP);
214
323
if(rc != GPG_ERR_NO_ERROR){
215
fprintf(stderr, "bad gpgme_engine_check_version: %s: %s\n",
216
gpgme_strsource(rc), gpgme_strerror(rc));
324
fprintf_plus(stderr, "bad gpgme_engine_check_version: %s: %s\n",
325
gpgme_strsource(rc), gpgme_strerror(rc));
220
/* Set GPGME home directory for the OpenPGP engine only */
329
/* Set GPGME home directory for the OpenPGP engine only */
221
330
rc = gpgme_get_engine_info(&engine_info);
222
331
if(rc != GPG_ERR_NO_ERROR){
223
fprintf(stderr, "bad gpgme_get_engine_info: %s: %s\n",
224
gpgme_strsource(rc), gpgme_strerror(rc));
332
fprintf_plus(stderr, "bad gpgme_get_engine_info: %s: %s\n",
333
gpgme_strsource(rc), gpgme_strerror(rc));
227
336
while(engine_info != NULL){
266
379
ssize_t plaintext_length = 0;
269
fprintf(stderr, "Trying to decrypt OpenPGP data\n");
382
fprintf_plus(stderr, "Trying to decrypt OpenPGP data\n");
272
385
/* Create new GPGME data buffer from memory cryptotext */
273
386
rc = gpgme_data_new_from_mem(&dh_crypto, cryptotext, crypto_size,
275
388
if(rc != GPG_ERR_NO_ERROR){
276
fprintf(stderr, "bad gpgme_data_new_from_mem: %s: %s\n",
277
gpgme_strsource(rc), gpgme_strerror(rc));
389
fprintf_plus(stderr, "bad gpgme_data_new_from_mem: %s: %s\n",
390
gpgme_strsource(rc), gpgme_strerror(rc));
281
394
/* Create new empty GPGME data buffer for the plaintext */
282
395
rc = gpgme_data_new(&dh_plain);
283
396
if(rc != GPG_ERR_NO_ERROR){
284
fprintf(stderr, "bad gpgme_data_new: %s: %s\n",
285
gpgme_strsource(rc), gpgme_strerror(rc));
397
fprintf_plus(stderr, "Mandos plugin mandos-client: "
398
"bad gpgme_data_new: %s: %s\n",
399
gpgme_strsource(rc), gpgme_strerror(rc));
286
400
gpgme_data_release(dh_crypto);
290
404
/* Decrypt data from the cryptotext data buffer to the plaintext
292
rc = gpgme_op_decrypt(mc.ctx, dh_crypto, dh_plain);
406
rc = gpgme_op_decrypt(mc->ctx, dh_crypto, dh_plain);
293
407
if(rc != GPG_ERR_NO_ERROR){
294
fprintf(stderr, "bad gpgme_op_decrypt: %s: %s\n",
295
gpgme_strsource(rc), gpgme_strerror(rc));
408
fprintf_plus(stderr, "bad gpgme_op_decrypt: %s: %s\n",
409
gpgme_strsource(rc), gpgme_strerror(rc));
296
410
plaintext_length = -1;
298
412
gpgme_decrypt_result_t result;
299
result = gpgme_op_decrypt_result(mc.ctx);
413
result = gpgme_op_decrypt_result(mc->ctx);
300
414
if(result == NULL){
301
fprintf(stderr, "gpgme_op_decrypt_result failed\n");
415
fprintf_plus(stderr, "gpgme_op_decrypt_result failed\n");
303
fprintf(stderr, "Unsupported algorithm: %s\n",
304
result->unsupported_algorithm);
305
fprintf(stderr, "Wrong key usage: %u\n",
306
result->wrong_key_usage);
417
fprintf_plus(stderr, "Unsupported algorithm: %s\n",
418
result->unsupported_algorithm);
419
fprintf_plus(stderr, "Wrong key usage: %u\n",
420
result->wrong_key_usage);
307
421
if(result->file_name != NULL){
308
fprintf(stderr, "File name: %s\n", result->file_name);
422
fprintf_plus(stderr, "File name: %s\n", result->file_name);
310
424
gpgme_recipient_t recipient;
311
425
recipient = result->recipients;
312
426
while(recipient != NULL){
313
fprintf(stderr, "Public key algorithm: %s\n",
314
gpgme_pubkey_algo_name(recipient->pubkey_algo));
315
fprintf(stderr, "Key ID: %s\n", recipient->keyid);
316
fprintf(stderr, "Secret key available: %s\n",
317
recipient->status == GPG_ERR_NO_SECKEY
427
fprintf_plus(stderr, "Public key algorithm: %s\n",
428
gpgme_pubkey_algo_name
429
(recipient->pubkey_algo));
430
fprintf_plus(stderr, "Key ID: %s\n", recipient->keyid);
431
fprintf_plus(stderr, "Secret key available: %s\n",
432
recipient->status == GPG_ERR_NO_SECKEY
319
434
recipient = recipient->next;
418
543
/* OpenPGP credentials */
419
gnutls_certificate_allocate_credentials(&mc.cred);
544
ret = gnutls_certificate_allocate_credentials(&mc->cred);
420
545
if(ret != GNUTLS_E_SUCCESS){
421
fprintf(stderr, "GnuTLS memory error: %s\n", /* Spurious warning
425
safer_gnutls_strerror(ret));
546
fprintf_plus(stderr, "GnuTLS memory error: %s\n",
547
safer_gnutls_strerror(ret));
426
548
gnutls_global_deinit();
431
fprintf(stderr, "Attempting to use OpenPGP public key %s and"
432
" secret key %s as GnuTLS credentials\n", pubkeyfilename,
553
fprintf_plus(stderr, "Attempting to use OpenPGP public key %s and"
554
" secret key %s as GnuTLS credentials\n",
436
559
ret = gnutls_certificate_set_openpgp_key_file
437
(mc.cred, pubkeyfilename, seckeyfilename,
560
(mc->cred, pubkeyfilename, seckeyfilename,
438
561
GNUTLS_OPENPGP_FMT_BASE64);
439
562
if(ret != GNUTLS_E_SUCCESS){
441
"Error[%d] while reading the OpenPGP key pair ('%s',"
442
" '%s')\n", ret, pubkeyfilename, seckeyfilename);
443
fprintf(stderr, "The GnuTLS error is: %s\n",
444
safer_gnutls_strerror(ret));
564
"Error[%d] while reading the OpenPGP key pair ('%s',"
565
" '%s')\n", ret, pubkeyfilename, seckeyfilename);
566
fprintf_plus(stderr, "The GnuTLS error is: %s\n",
567
safer_gnutls_strerror(ret));
448
571
/* GnuTLS server initialization */
449
ret = gnutls_dh_params_init(&mc.dh_params);
450
if(ret != GNUTLS_E_SUCCESS){
451
fprintf(stderr, "Error in GnuTLS DH parameter initialization:"
452
" %s\n", safer_gnutls_strerror(ret));
455
ret = gnutls_dh_params_generate2(mc.dh_params, mc.dh_bits);
456
if(ret != GNUTLS_E_SUCCESS){
457
fprintf(stderr, "Error in GnuTLS prime generation: %s\n",
458
safer_gnutls_strerror(ret));
462
gnutls_certificate_set_dh_params(mc.cred, mc.dh_params);
572
ret = gnutls_dh_params_init(&mc->dh_params);
573
if(ret != GNUTLS_E_SUCCESS){
574
fprintf_plus(stderr, "Error in GnuTLS DH parameter"
575
" initialization: %s\n",
576
safer_gnutls_strerror(ret));
579
/* If a Diffie-Hellman parameters file was given, try to use it */
580
if(dhparamsfilename != NULL){
581
gnutls_datum_t params = { .data = NULL, .size = 0 };
583
int dhpfile = open(dhparamsfilename, O_RDONLY);
586
dhparamsfilename = NULL;
589
size_t params_capacity = 0;
591
params_capacity = incbuffer((char **)¶ms.data,
593
(size_t)params_capacity);
594
if(params_capacity == 0){
595
perror_plus("incbuffer");
598
dhparamsfilename = NULL;
601
ssize_t bytes_read = read(dhpfile,
602
params.data + params.size,
608
/* check bytes_read for failure */
613
dhparamsfilename = NULL;
616
params.size += (unsigned int)bytes_read;
618
if(params.data == NULL){
619
dhparamsfilename = NULL;
621
if(dhparamsfilename == NULL){
624
ret = gnutls_dh_params_import_pkcs3(mc->dh_params, ¶ms,
625
GNUTLS_X509_FMT_PEM);
626
if(ret != GNUTLS_E_SUCCESS){
627
fprintf_plus(stderr, "Failed to parse DH parameters in file"
628
" \"%s\": %s\n", dhparamsfilename,
629
safer_gnutls_strerror(ret));
630
dhparamsfilename = NULL;
634
if(dhparamsfilename == NULL){
635
if(mc->dh_bits == 0){
636
/* Find out the optimal number of DH bits */
637
/* Try to read the private key file */
638
gnutls_datum_t buffer = { .data = NULL, .size = 0 };
640
int secfile = open(seckeyfilename, O_RDONLY);
645
size_t buffer_capacity = 0;
647
buffer_capacity = incbuffer((char **)&buffer.data,
649
(size_t)buffer_capacity);
650
if(buffer_capacity == 0){
651
perror_plus("incbuffer");
656
ssize_t bytes_read = read(secfile,
657
buffer.data + buffer.size,
663
/* check bytes_read for failure */
670
buffer.size += (unsigned int)bytes_read;
674
/* If successful, use buffer to parse private key */
675
gnutls_sec_param_t sec_param = GNUTLS_SEC_PARAM_ULTRA;
676
if(buffer.data != NULL){
678
gnutls_openpgp_privkey_t privkey = NULL;
679
ret = gnutls_openpgp_privkey_init(&privkey);
680
if(ret != GNUTLS_E_SUCCESS){
681
fprintf_plus(stderr, "Error initializing OpenPGP key"
683
safer_gnutls_strerror(ret));
687
ret = gnutls_openpgp_privkey_import
688
(privkey, &buffer, GNUTLS_OPENPGP_FMT_BASE64, "", 0);
689
if(ret != GNUTLS_E_SUCCESS){
690
fprintf_plus(stderr, "Error importing OpenPGP key : %s",
691
safer_gnutls_strerror(ret));
697
/* Use private key to suggest an appropriate
699
sec_param = gnutls_openpgp_privkey_sec_param(privkey);
700
gnutls_openpgp_privkey_deinit(privkey);
702
fprintf_plus(stderr, "This OpenPGP key implies using"
703
" a GnuTLS security parameter \"%s\".\n",
704
safe_string(gnutls_sec_param_get_name
710
if(sec_param == GNUTLS_SEC_PARAM_UNKNOWN){
711
/* Err on the side of caution */
712
sec_param = GNUTLS_SEC_PARAM_ULTRA;
714
fprintf_plus(stderr, "Falling back to security parameter"
716
safe_string(gnutls_sec_param_get_name
721
uret = gnutls_sec_param_to_pk_bits(GNUTLS_PK_DH, sec_param);
725
fprintf_plus(stderr, "A \"%s\" GnuTLS security parameter"
726
" implies %u DH bits; using that.\n",
727
safe_string(gnutls_sec_param_get_name
732
fprintf_plus(stderr, "Failed to get implied number of DH"
733
" bits for security parameter \"%s\"): %s\n",
734
safe_string(gnutls_sec_param_get_name
736
safer_gnutls_strerror(ret));
740
fprintf_plus(stderr, "DH bits explicitly set to %u\n",
743
ret = gnutls_dh_params_generate2(mc->dh_params, mc->dh_bits);
744
if(ret != GNUTLS_E_SUCCESS){
745
fprintf_plus(stderr, "Error in GnuTLS prime generation (%u"
746
" bits): %s\n", mc->dh_bits,
747
safer_gnutls_strerror(ret));
751
gnutls_certificate_set_dh_params(mc->cred, mc->dh_params);
468
gnutls_certificate_free_credentials(mc.cred);
757
gnutls_certificate_free_credentials(mc->cred);
469
758
gnutls_global_deinit();
470
gnutls_dh_params_deinit(mc.dh_params);
759
gnutls_dh_params_deinit(mc->dh_params);
474
static int init_gnutls_session(gnutls_session_t *session){
763
__attribute__((nonnull, warn_unused_result))
764
static int init_gnutls_session(gnutls_session_t *session,
476
767
/* GnuTLS session creation */
477
ret = gnutls_init(session, GNUTLS_SERVER);
769
ret = gnutls_init(session, GNUTLS_SERVER);
773
} while(ret == GNUTLS_E_INTERRUPTED or ret == GNUTLS_E_AGAIN);
478
774
if(ret != GNUTLS_E_SUCCESS){
479
fprintf(stderr, "Error in GnuTLS session initialization: %s\n",
480
safer_gnutls_strerror(ret));
776
"Error in GnuTLS session initialization: %s\n",
777
safer_gnutls_strerror(ret));
485
ret = gnutls_priority_set_direct(*session, mc.priority, &err);
783
ret = gnutls_priority_set_direct(*session, mc->priority, &err);
785
gnutls_deinit(*session);
788
} while(ret == GNUTLS_E_INTERRUPTED or ret == GNUTLS_E_AGAIN);
486
789
if(ret != GNUTLS_E_SUCCESS){
487
fprintf(stderr, "Syntax error at: %s\n", err);
488
fprintf(stderr, "GnuTLS error: %s\n",
489
safer_gnutls_strerror(ret));
790
fprintf_plus(stderr, "Syntax error at: %s\n", err);
791
fprintf_plus(stderr, "GnuTLS error: %s\n",
792
safer_gnutls_strerror(ret));
490
793
gnutls_deinit(*session);
495
ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,
799
ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,
802
gnutls_deinit(*session);
805
} while(ret == GNUTLS_E_INTERRUPTED or ret == GNUTLS_E_AGAIN);
497
806
if(ret != GNUTLS_E_SUCCESS){
498
fprintf(stderr, "Error setting GnuTLS credentials: %s\n",
499
safer_gnutls_strerror(ret));
807
fprintf_plus(stderr, "Error setting GnuTLS credentials: %s\n",
808
safer_gnutls_strerror(ret));
500
809
gnutls_deinit(*session);
504
813
/* ignore client certificate if any. */
505
gnutls_certificate_server_set_request(*session,
508
gnutls_dh_set_prime_bits(*session, mc.dh_bits);
814
gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);
514
820
static void empty_log(__attribute__((unused)) AvahiLogLevel level,
515
821
__attribute__((unused)) const char *txt){}
823
/* Set effective uid to 0, return errno */
824
__attribute__((warn_unused_result))
825
error_t raise_privileges(void){
826
error_t old_errno = errno;
827
error_t ret_errno = 0;
828
if(seteuid(0) == -1){
835
/* Set effective and real user ID to 0. Return errno. */
836
__attribute__((warn_unused_result))
837
error_t raise_privileges_permanently(void){
838
error_t old_errno = errno;
839
error_t ret_errno = raise_privileges();
851
/* Set effective user ID to unprivileged saved user ID */
852
__attribute__((warn_unused_result))
853
error_t lower_privileges(void){
854
error_t old_errno = errno;
855
error_t ret_errno = 0;
856
if(seteuid(uid) == -1){
863
/* Lower privileges permanently */
864
__attribute__((warn_unused_result))
865
error_t lower_privileges_permanently(void){
866
error_t old_errno = errno;
867
error_t ret_errno = 0;
868
if(setuid(uid) == -1){
875
/* Helper function to add_local_route() and delete_local_route() */
876
__attribute__((nonnull, warn_unused_result))
877
static bool add_delete_local_route(const bool add,
879
AvahiIfIndex if_index){
881
char helper[] = "mandos-client-iprouteadddel";
882
char add_arg[] = "add";
883
char delete_arg[] = "delete";
884
char debug_flag[] = "--debug";
885
char *pluginhelperdir = getenv("MANDOSPLUGINHELPERDIR");
886
if(pluginhelperdir == NULL){
888
fprintf_plus(stderr, "MANDOSPLUGINHELPERDIR environment"
889
" variable not set; cannot run helper\n");
894
char interface[IF_NAMESIZE];
895
if(if_indextoname((unsigned int)if_index, interface) == NULL){
896
perror_plus("if_indextoname");
900
int devnull = (int)TEMP_FAILURE_RETRY(open("/dev/null", O_RDONLY));
902
perror_plus("open(\"/dev/null\", O_RDONLY)");
908
/* Raise privileges */
909
errno = raise_privileges_permanently();
911
perror_plus("Failed to raise privileges");
912
/* _exit(EX_NOPERM); */
918
perror_plus("setgid");
921
/* Reset supplementary groups */
923
ret = setgroups(0, NULL);
925
perror_plus("setgroups");
929
ret = dup2(devnull, STDIN_FILENO);
931
perror_plus("dup2(devnull, STDIN_FILENO)");
934
ret = (int)TEMP_FAILURE_RETRY(close(devnull));
936
perror_plus("close");
939
ret = dup2(STDERR_FILENO, STDOUT_FILENO);
941
perror_plus("dup2(STDERR_FILENO, STDOUT_FILENO)");
944
int helperdir_fd = (int)TEMP_FAILURE_RETRY(open(pluginhelperdir,
949
if(helperdir_fd == -1){
951
_exit(EX_UNAVAILABLE);
953
int helper_fd = (int)TEMP_FAILURE_RETRY(openat(helperdir_fd,
956
perror_plus("openat");
957
_exit(EX_UNAVAILABLE);
959
TEMP_FAILURE_RETRY(close(helperdir_fd));
961
#pragma GCC diagnostic push
962
#pragma GCC diagnostic ignored "-Wcast-qual"
964
if(fexecve(helper_fd, (char *const [])
965
{ helper, add ? add_arg : delete_arg, (char *)address,
966
interface, debug ? debug_flag : NULL, NULL },
969
#pragma GCC diagnostic pop
971
perror_plus("fexecve");
983
pret = waitpid(pid, &status, 0);
984
if(pret == -1 and errno == EINTR and quit_now){
985
int errno_raising = 0;
986
if((errno = raise_privileges()) != 0){
987
errno_raising = errno;
988
perror_plus("Failed to raise privileges in order to"
989
" kill helper program");
991
if(kill(pid, SIGTERM) == -1){
994
if((errno_raising == 0) and (errno = lower_privileges()) != 0){
995
perror_plus("Failed to lower privileges after killing"
1000
} while(pret == -1 and errno == EINTR);
1002
perror_plus("waitpid");
1005
if(WIFEXITED(status)){
1006
if(WEXITSTATUS(status) != 0){
1007
fprintf_plus(stderr, "Error: iprouteadddel exited"
1008
" with status %d\n", WEXITSTATUS(status));
1013
if(WIFSIGNALED(status)){
1014
fprintf_plus(stderr, "Error: iprouteadddel died by"
1015
" signal %d\n", WTERMSIG(status));
1018
fprintf_plus(stderr, "Error: iprouteadddel crashed\n");
1022
__attribute__((nonnull, warn_unused_result))
1023
static bool add_local_route(const char *address,
1024
AvahiIfIndex if_index){
1026
fprintf_plus(stderr, "Adding route to %s\n", address);
1028
return add_delete_local_route(true, address, if_index);
1031
__attribute__((nonnull, warn_unused_result))
1032
static bool delete_local_route(const char *address,
1033
AvahiIfIndex if_index){
1035
fprintf_plus(stderr, "Removing route to %s\n", address);
1037
return add_delete_local_route(false, address, if_index);
517
1040
/* Called when a Mandos server is found */
518
static int start_mandos_communication(const char *ip, uint16_t port,
1041
__attribute__((nonnull, warn_unused_result))
1042
static int start_mandos_communication(const char *ip, in_port_t port,
519
1043
AvahiIfIndex if_index,
1044
int af, mandos_context *mc){
1045
int ret, tcp_sd = -1;
524
struct sockaddr_in in;
525
struct sockaddr_in6 in6;
1047
struct sockaddr_storage to;
527
1048
char *buffer = NULL;
528
char *decrypted_buffer;
1049
char *decrypted_buffer = NULL;
529
1050
size_t buffer_length = 0;
530
1051
size_t buffer_capacity = 0;
531
ssize_t decrypted_buffer_size;
534
1054
gnutls_session_t session;
535
1055
int pf; /* Protocol family */
1056
bool route_added = false;
545
fprintf(stderr, "Bad address family: %d\n", af);
1073
fprintf_plus(stderr, "Bad address family: %d\n", af);
549
ret = init_gnutls_session(&session);
1078
/* If the interface is specified and we have a list of interfaces */
1079
if(if_index != AVAHI_IF_UNSPEC and mc->interfaces != NULL){
1080
/* Check if the interface is one of the interfaces we are using */
1083
char *interface = NULL;
1084
while((interface=argz_next(mc->interfaces, mc->interfaces_size,
1086
if(if_nametoindex(interface) == (unsigned int)if_index){
1093
/* This interface does not match any in the list, so we don't
1094
connect to the server */
1096
char interface[IF_NAMESIZE];
1097
if(if_indextoname((unsigned int)if_index, interface) == NULL){
1098
perror_plus("if_indextoname");
1100
fprintf_plus(stderr, "Skipping server on non-used interface"
1102
if_indextoname((unsigned int)if_index,
1110
ret = init_gnutls_session(&session, mc);
555
fprintf(stderr, "Setting up a TCP connection to %s, port %" PRIu16
1116
fprintf_plus(stderr, "Setting up a TCP connection to %s, port %"
1117
PRIuMAX "\n", ip, (uintmax_t)port);
559
tcp_sd = socket(pf, SOCK_STREAM, 0);
1120
tcp_sd = socket(pf, SOCK_STREAM | SOCK_CLOEXEC, 0);
1123
perror_plus("socket");
565
1133
memset(&to, 0, sizeof(to));
566
1134
if(af == AF_INET6){
567
to.in6.sin6_family = (sa_family_t)af;
568
ret = inet_pton(af, ip, &to.in6.sin6_addr);
1135
((struct sockaddr_in6 *)&to)->sin6_family = (sa_family_t)af;
1136
ret = inet_pton(af, ip, &((struct sockaddr_in6 *)&to)->sin6_addr);
569
1137
} else { /* IPv4 */
570
to.in.sin_family = (sa_family_t)af;
571
ret = inet_pton(af, ip, &to.in.sin_addr);
1138
((struct sockaddr_in *)&to)->sin_family = (sa_family_t)af;
1139
ret = inet_pton(af, ip, &((struct sockaddr_in *)&to)->sin_addr);
1143
perror_plus("inet_pton");
578
fprintf(stderr, "Bad address: %s\n", ip);
1149
fprintf_plus(stderr, "Bad address: %s\n", ip);
581
1153
if(af == AF_INET6){
582
to.in6.sin6_port = htons(port); /* Spurious warnings from
584
-Wunreachable-code */
586
if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */
587
(&to.in6.sin6_addr)){ /* -Wstrict-aliasing=2 or lower and
1154
((struct sockaddr_in6 *)&to)->sin6_port = htons(port);
1155
if(IN6_IS_ADDR_LINKLOCAL
1156
(&((struct sockaddr_in6 *)&to)->sin6_addr)){
589
1157
if(if_index == AVAHI_IF_UNSPEC){
590
fprintf(stderr, "An IPv6 link-local address is incomplete"
591
" without a network interface\n");
1158
fprintf_plus(stderr, "An IPv6 link-local address is"
1159
" incomplete without a network interface\n");
594
1163
/* Set the network interface number as scope */
595
to.in6.sin6_scope_id = (uint32_t)if_index;
1164
((struct sockaddr_in6 *)&to)->sin6_scope_id = (uint32_t)if_index;
598
to.in.sin_port = htons(port); /* Spurious warnings from
600
-Wunreachable-code */
1167
((struct sockaddr_in *)&to)->sin_port = htons(port);
604
1176
if(af == AF_INET6 and if_index != AVAHI_IF_UNSPEC){
605
1177
char interface[IF_NAMESIZE];
606
1178
if(if_indextoname((unsigned int)if_index, interface) == NULL){
607
perror("if_indextoname");
1179
perror_plus("if_indextoname");
609
fprintf(stderr, "Connection to: %s%%%s, port %" PRIu16 "\n",
610
ip, interface, port);
1181
fprintf_plus(stderr, "Connection to: %s%%%s, port %" PRIuMAX
1182
"\n", ip, interface, (uintmax_t)port);
613
fprintf(stderr, "Connection to: %s, port %" PRIu16 "\n", ip,
1185
fprintf_plus(stderr, "Connection to: %s, port %" PRIuMAX "\n",
1186
ip, (uintmax_t)port);
616
1188
char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?
617
1189
INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";
620
pcret = inet_ntop(af, &(to.in6.sin6_addr), addrstr,
623
pcret = inet_ntop(af, &(to.in.sin_addr), addrstr,
629
if(strcmp(addrstr, ip) != 0){
630
fprintf(stderr, "Canonical address form: %s\n", addrstr);
636
ret = connect(tcp_sd, &to.in6, sizeof(to));
638
ret = connect(tcp_sd, &to.in, sizeof(to)); /* IPv4 */
1191
ret = getnameinfo((struct sockaddr *)&to,
1192
sizeof(struct sockaddr_in6),
1193
addrstr, sizeof(addrstr), NULL, 0,
1196
ret = getnameinfo((struct sockaddr *)&to,
1197
sizeof(struct sockaddr_in),
1198
addrstr, sizeof(addrstr), NULL, 0,
1201
if(ret == EAI_SYSTEM){
1202
perror_plus("getnameinfo");
1203
} else if(ret != 0) {
1204
fprintf_plus(stderr, "getnameinfo: %s", gai_strerror(ret));
1205
} else if(strcmp(addrstr, ip) != 0){
1206
fprintf_plus(stderr, "Canonical address form: %s\n", addrstr);
1217
ret = connect(tcp_sd, (struct sockaddr *)&to,
1218
sizeof(struct sockaddr_in6));
1220
ret = connect(tcp_sd, (struct sockaddr *)&to, /* IPv4 */
1221
sizeof(struct sockaddr_in));
1224
if(errno == ENETUNREACH
1225
and if_index != AVAHI_IF_UNSPEC
1226
and connect_to == NULL
1227
and not route_added and
1228
((af == AF_INET6 and not
1229
IN6_IS_ADDR_LINKLOCAL(&(((struct sockaddr_in6 *)
1231
or (af == AF_INET and
1232
/* Not a a IPv4LL address */
1233
(ntohl(((struct sockaddr_in *)&to)->sin_addr.s_addr)
1234
& 0xFFFF0000L) != 0xA9FE0000L))){
1235
/* Work around Avahi bug - Avahi does not announce link-local
1236
addresses if it has a global address, so local hosts with
1237
*only* a link-local address (e.g. Mandos clients) cannot
1238
connect to a Mandos server announced by Avahi on a server
1239
host with a global address. Work around this by retrying
1240
with an explicit route added with the server's address.
1242
Avahi bug reference:
1243
http://lists.freedesktop.org/archives/avahi/2010-February/001833.html
1244
https://bugs.debian.org/587961
1247
fprintf_plus(stderr, "Mandos server unreachable, trying"
1251
route_added = add_local_route(ip, if_index);
1257
if(errno != ECONNREFUSED or debug){
1259
perror_plus("connect");
645
1272
const char *out = mandos_protocol_version;
869
1601
case AVAHI_BROWSER_ALL_FOR_NOW:
870
1602
case AVAHI_BROWSER_CACHE_EXHAUSTED:
872
fprintf(stderr, "No Mandos server found, still searching...\n");
1604
fprintf_plus(stderr, "No Mandos server found, still"
878
sig_atomic_t quit_now = 0;
880
/* stop main loop after sigterm has been called */
881
static void handle_sigterm(__attribute__((unused)) int sig){
1611
/* Signal handler that stops main loop after SIGTERM */
1612
static void handle_sigterm(int sig){
1617
signal_received = sig;
886
1618
int old_errno = errno;
887
if(mc.simple_poll != NULL){
888
avahi_simple_poll_quit(mc.simple_poll);
1619
/* set main loop to exit */
1620
if(simple_poll != NULL){
1621
avahi_simple_poll_quit(simple_poll);
1626
__attribute__((nonnull, warn_unused_result))
1627
bool get_flags(const char *ifname, struct ifreq *ifr){
1631
int s = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1634
perror_plus("socket");
1638
strcpy(ifr->ifr_name, ifname);
1639
ret = ioctl(s, SIOCGIFFLAGS, ifr);
1643
perror_plus("ioctl SIOCGIFFLAGS");
1651
__attribute__((nonnull, warn_unused_result))
1652
bool good_flags(const char *ifname, const struct ifreq *ifr){
1654
/* Reject the loopback device */
1655
if(ifr->ifr_flags & IFF_LOOPBACK){
1657
fprintf_plus(stderr, "Rejecting loopback interface \"%s\"\n",
1662
/* Accept point-to-point devices only if connect_to is specified */
1663
if(connect_to != NULL and (ifr->ifr_flags & IFF_POINTOPOINT)){
1665
fprintf_plus(stderr, "Accepting point-to-point interface"
1666
" \"%s\"\n", ifname);
1670
/* Otherwise, reject non-broadcast-capable devices */
1671
if(not (ifr->ifr_flags & IFF_BROADCAST)){
1673
fprintf_plus(stderr, "Rejecting non-broadcast interface"
1674
" \"%s\"\n", ifname);
1678
/* Reject non-ARP interfaces (including dummy interfaces) */
1679
if(ifr->ifr_flags & IFF_NOARP){
1681
fprintf_plus(stderr, "Rejecting non-ARP interface \"%s\"\n",
1687
/* Accept this device */
1689
fprintf_plus(stderr, "Interface \"%s\" is good\n", ifname);
1695
* This function determines if a directory entry in /sys/class/net
1696
* corresponds to an acceptable network device.
1697
* (This function is passed to scandir(3) as a filter function.)
1699
__attribute__((nonnull, warn_unused_result))
1700
int good_interface(const struct dirent *if_entry){
1701
if(if_entry->d_name[0] == '.'){
1706
if(not get_flags(if_entry->d_name, &ifr)){
1708
fprintf_plus(stderr, "Failed to get flags for interface "
1709
"\"%s\"\n", if_entry->d_name);
1714
if(not good_flags(if_entry->d_name, &ifr)){
1721
* This function determines if a network interface is up.
1723
__attribute__((nonnull, warn_unused_result))
1724
bool interface_is_up(const char *interface){
1726
if(not get_flags(interface, &ifr)){
1728
fprintf_plus(stderr, "Failed to get flags for interface "
1729
"\"%s\"\n", interface);
1734
return (bool)(ifr.ifr_flags & IFF_UP);
1738
* This function determines if a network interface is running
1740
__attribute__((nonnull, warn_unused_result))
1741
bool interface_is_running(const char *interface){
1743
if(not get_flags(interface, &ifr)){
1745
fprintf_plus(stderr, "Failed to get flags for interface "
1746
"\"%s\"\n", interface);
1751
return (bool)(ifr.ifr_flags & IFF_RUNNING);
1754
__attribute__((nonnull, pure, warn_unused_result))
1755
int notdotentries(const struct dirent *direntry){
1756
/* Skip "." and ".." */
1757
if(direntry->d_name[0] == '.'
1758
and (direntry->d_name[1] == '\0'
1759
or (direntry->d_name[1] == '.'
1760
and direntry->d_name[2] == '\0'))){
1766
/* Is this directory entry a runnable program? */
1767
__attribute__((nonnull, warn_unused_result))
1768
int runnable_hook(const struct dirent *direntry){
1773
if((direntry->d_name)[0] == '\0'){
1778
sret = strspn(direntry->d_name, "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
1779
"abcdefghijklmnopqrstuvwxyz"
1782
if((direntry->d_name)[sret] != '\0'){
1783
/* Contains non-allowed characters */
1785
fprintf_plus(stderr, "Ignoring hook \"%s\" with bad name\n",
1791
ret = fstatat(hookdir_fd, direntry->d_name, &st, 0);
1794
perror_plus("Could not stat hook");
1798
if(not (S_ISREG(st.st_mode))){
1799
/* Not a regular file */
1801
fprintf_plus(stderr, "Ignoring hook \"%s\" - not a file\n",
1806
if(not (st.st_mode & (S_IXUSR | S_IXGRP | S_IXOTH))){
1807
/* Not executable */
1809
fprintf_plus(stderr, "Ignoring hook \"%s\" - not executable\n",
1815
fprintf_plus(stderr, "Hook \"%s\" is acceptable\n",
1821
__attribute__((nonnull, warn_unused_result))
1822
int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,
1823
mandos_context *mc){
1825
struct timespec now;
1826
struct timespec waited_time;
1827
intmax_t block_time;
1830
if(mc->current_server == NULL){
1832
fprintf_plus(stderr, "Wait until first server is found."
1835
ret = avahi_simple_poll_iterate(s, -1);
1838
fprintf_plus(stderr, "Check current_server if we should run"
1841
/* the current time */
1842
ret = clock_gettime(CLOCK_MONOTONIC, &now);
1844
perror_plus("clock_gettime");
1847
/* Calculating in ms how long time between now and server
1848
who we visted longest time ago. Now - last seen. */
1849
waited_time.tv_sec = (now.tv_sec
1850
- mc->current_server->last_seen.tv_sec);
1851
waited_time.tv_nsec = (now.tv_nsec
1852
- mc->current_server->last_seen.tv_nsec);
1853
/* total time is 10s/10,000ms.
1854
Converting to s from ms by dividing by 1,000,
1855
and ns to ms by dividing by 1,000,000. */
1856
block_time = ((retry_interval
1857
- ((intmax_t)waited_time.tv_sec * 1000))
1858
- ((intmax_t)waited_time.tv_nsec / 1000000));
1861
fprintf_plus(stderr, "Blocking for %" PRIdMAX " ms\n",
1865
if(block_time <= 0){
1866
ret = start_mandos_communication(mc->current_server->ip,
1867
mc->current_server->port,
1868
mc->current_server->if_index,
1869
mc->current_server->af, mc);
1871
avahi_simple_poll_quit(s);
1874
ret = clock_gettime(CLOCK_MONOTONIC,
1875
&mc->current_server->last_seen);
1877
perror_plus("clock_gettime");
1880
mc->current_server = mc->current_server->next;
1881
block_time = 0; /* Call avahi to find new Mandos
1882
servers, but don't block */
1885
ret = avahi_simple_poll_iterate(s, (int)block_time);
1888
if(ret > 0 or errno != EINTR){
1889
return (ret != 1) ? ret : 0;
1895
__attribute__((nonnull))
1896
void run_network_hooks(const char *mode, const char *interface,
1898
struct dirent **direntries = NULL;
1899
if(hookdir_fd == -1){
1900
hookdir_fd = open(hookdir, O_RDONLY | O_DIRECTORY | O_PATH
1902
if(hookdir_fd == -1){
1903
if(errno == ENOENT){
1905
fprintf_plus(stderr, "Network hook directory \"%s\" not"
1906
" found\n", hookdir);
1909
perror_plus("open");
1915
#if __GLIBC_PREREQ(2, 15)
1916
int numhooks = scandirat(hookdir_fd, ".", &direntries,
1917
runnable_hook, alphasort);
1918
#else /* not __GLIBC_PREREQ(2, 15) */
1919
int numhooks = scandir(hookdir, &direntries, runnable_hook,
1921
#endif /* not __GLIBC_PREREQ(2, 15) */
1922
#else /* not __GLIBC__ */
1923
int numhooks = scandir(hookdir, &direntries, runnable_hook,
1925
#endif /* not __GLIBC__ */
1927
perror_plus("scandir");
1930
struct dirent *direntry;
1932
int devnull = (int)TEMP_FAILURE_RETRY(open("/dev/null", O_RDONLY));
1934
perror_plus("open(\"/dev/null\", O_RDONLY)");
1937
for(int i = 0; i < numhooks; i++){
1938
direntry = direntries[i];
1940
fprintf_plus(stderr, "Running network hook \"%s\"\n",
1943
pid_t hook_pid = fork();
1946
/* Raise privileges */
1947
errno = raise_privileges_permanently();
1949
perror_plus("Failed to raise privileges");
1956
perror_plus("setgid");
1959
/* Reset supplementary groups */
1961
ret = setgroups(0, NULL);
1963
perror_plus("setgroups");
1966
ret = setenv("MANDOSNETHOOKDIR", hookdir, 1);
1968
perror_plus("setenv");
1971
ret = setenv("DEVICE", interface, 1);
1973
perror_plus("setenv");
1976
ret = setenv("VERBOSITY", debug ? "1" : "0", 1);
1978
perror_plus("setenv");
1981
ret = setenv("MODE", mode, 1);
1983
perror_plus("setenv");
1987
ret = asprintf(&delaystring, "%f", (double)delay);
1989
perror_plus("asprintf");
1992
ret = setenv("DELAY", delaystring, 1);
1995
perror_plus("setenv");
1999
if(connect_to != NULL){
2000
ret = setenv("CONNECT", connect_to, 1);
2002
perror_plus("setenv");
2006
int hook_fd = (int)TEMP_FAILURE_RETRY(openat(hookdir_fd,
2010
perror_plus("openat");
2011
_exit(EXIT_FAILURE);
2013
if((int)TEMP_FAILURE_RETRY(close(hookdir_fd)) == -1){
2014
perror_plus("close");
2015
_exit(EXIT_FAILURE);
2017
ret = dup2(devnull, STDIN_FILENO);
2019
perror_plus("dup2(devnull, STDIN_FILENO)");
2022
ret = (int)TEMP_FAILURE_RETRY(close(devnull));
2024
perror_plus("close");
2027
ret = dup2(STDERR_FILENO, STDOUT_FILENO);
2029
perror_plus("dup2(STDERR_FILENO, STDOUT_FILENO)");
2032
if(fexecve(hook_fd, (char *const []){ direntry->d_name, NULL },
2034
perror_plus("fexecve");
2035
_exit(EXIT_FAILURE);
2039
perror_plus("fork");
2044
if(TEMP_FAILURE_RETRY(waitpid(hook_pid, &status, 0)) == -1){
2045
perror_plus("waitpid");
2049
if(WIFEXITED(status)){
2050
if(WEXITSTATUS(status) != 0){
2051
fprintf_plus(stderr, "Warning: network hook \"%s\" exited"
2052
" with status %d\n", direntry->d_name,
2053
WEXITSTATUS(status));
2057
} else if(WIFSIGNALED(status)){
2058
fprintf_plus(stderr, "Warning: network hook \"%s\" died by"
2059
" signal %d\n", direntry->d_name,
2064
fprintf_plus(stderr, "Warning: network hook \"%s\""
2065
" crashed\n", direntry->d_name);
2071
fprintf_plus(stderr, "Network hook \"%s\" ran successfully\n",
2077
if((int)TEMP_FAILURE_RETRY(close(hookdir_fd)) == -1){
2078
perror_plus("close");
2085
__attribute__((nonnull, warn_unused_result))
2086
error_t bring_up_interface(const char *const interface,
2088
error_t old_errno = errno;
2090
struct ifreq network;
2091
unsigned int if_index = if_nametoindex(interface);
2093
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
2103
if(not interface_is_up(interface)){
2104
error_t ret_errno = 0, ioctl_errno = 0;
2105
if(not get_flags(interface, &network)){
2107
fprintf_plus(stderr, "Failed to get flags for interface "
2108
"\"%s\"\n", interface);
2112
network.ifr_flags |= IFF_UP; /* set flag */
2114
int sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
2117
perror_plus("socket");
2123
ret = (int)TEMP_FAILURE_RETRY(close(sd));
2125
perror_plus("close");
2132
fprintf_plus(stderr, "Bringing up interface \"%s\"\n",
2136
/* Raise privileges */
2137
ret_errno = raise_privileges();
2140
perror_plus("Failed to raise privileges");
2145
bool restore_loglevel = false;
2147
/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO
2148
messages about the network interface to mess up the prompt */
2149
ret_linux = klogctl(8, NULL, 5);
2150
if(ret_linux == -1){
2151
perror_plus("klogctl");
2153
restore_loglevel = true;
2156
#endif /* __linux__ */
2157
int ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
2158
ioctl_errno = errno;
2160
if(restore_loglevel){
2161
ret_linux = klogctl(7, NULL, 0);
2162
if(ret_linux == -1){
2163
perror_plus("klogctl");
2166
#endif /* __linux__ */
2168
/* If raise_privileges() succeeded above */
2170
/* Lower privileges */
2171
ret_errno = lower_privileges();
2174
perror_plus("Failed to lower privileges");
2178
/* Close the socket */
2179
ret = (int)TEMP_FAILURE_RETRY(close(sd));
2181
perror_plus("close");
2184
if(ret_setflags == -1){
2185
errno = ioctl_errno;
2186
perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");
2191
fprintf_plus(stderr, "Interface \"%s\" is already up; good\n",
2195
/* Sleep checking until interface is running.
2196
Check every 0.25s, up to total time of delay */
2197
for(int i=0; i < delay * 4; i++){
2198
if(interface_is_running(interface)){
2201
struct timespec sleeptime = { .tv_nsec = 250000000 };
2202
ret = nanosleep(&sleeptime, NULL);
2203
if(ret == -1 and errno != EINTR){
2204
perror_plus("nanosleep");
2212
__attribute__((nonnull, warn_unused_result))
2213
error_t take_down_interface(const char *const interface){
2214
error_t old_errno = errno;
2215
struct ifreq network;
2216
unsigned int if_index = if_nametoindex(interface);
2218
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
2222
if(interface_is_up(interface)){
2223
error_t ret_errno = 0, ioctl_errno = 0;
2224
if(not get_flags(interface, &network) and debug){
2226
fprintf_plus(stderr, "Failed to get flags for interface "
2227
"\"%s\"\n", interface);
2231
network.ifr_flags &= ~(short)IFF_UP; /* clear flag */
2233
int sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
2236
perror_plus("socket");
2242
fprintf_plus(stderr, "Taking down interface \"%s\"\n",
2246
/* Raise privileges */
2247
ret_errno = raise_privileges();
2250
perror_plus("Failed to raise privileges");
2253
int ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
2254
ioctl_errno = errno;
2256
/* If raise_privileges() succeeded above */
2258
/* Lower privileges */
2259
ret_errno = lower_privileges();
2262
perror_plus("Failed to lower privileges");
2266
/* Close the socket */
2267
int ret = (int)TEMP_FAILURE_RETRY(close(sd));
2269
perror_plus("close");
2272
if(ret_setflags == -1){
2273
errno = ioctl_errno;
2274
perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");
2279
fprintf_plus(stderr, "Interface \"%s\" is already down; odd\n",
893
2287
int main(int argc, char *argv[]){
2288
mandos_context mc = { .server = NULL, .dh_bits = 0,
2289
.priority = "SECURE256:!CTYPE-X.509:"
2290
"+CTYPE-OPENPGP:!RSA", .current_server = NULL,
2291
.interfaces = NULL, .interfaces_size = 0 };
894
2292
AvahiSServiceBrowser *sb = NULL;
897
2295
intmax_t tmpmax;
899
2297
int exitcode = EXIT_SUCCESS;
900
const char *interface = "eth0";
901
struct ifreq network;
903
bool interface_taken_up = false;
906
char *connect_to = NULL;
907
char tempdir[] = "/tmp/mandosXXXXXX";
908
bool tempdir_created = false;
2298
char *interfaces_to_take_down = NULL;
2299
size_t interfaces_to_take_down_size = 0;
2300
char run_tempdir[] = "/run/tmp/mandosXXXXXX";
2301
char old_tempdir[] = "/tmp/mandosXXXXXX";
2302
char *tempdir = NULL;
909
2303
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
910
2304
const char *seckey = PATHDIR "/" SECKEY;
911
2305
const char *pubkey = PATHDIR "/" PUBKEY;
2306
const char *dh_params_file = NULL;
2307
char *interfaces_hooks = NULL;
913
2309
bool gnutls_initialized = false;
914
2310
bool gpgme_initialized = false;
915
2311
float delay = 2.5f;
2312
double retry_interval = 10; /* 10s between trying a server and
2313
retrying the same server again */
917
struct sigaction old_sigterm_action;
2315
struct sigaction old_sigterm_action = { .sa_handler = SIG_DFL };
918
2316
struct sigaction sigterm_action = { .sa_handler = handle_sigterm };
2321
/* Lower any group privileges we might have, just to be safe */
2325
perror_plus("setgid");
2328
/* Lower user privileges (temporarily) */
2332
perror_plus("seteuid");
921
2340
struct argp_option options[] = {
922
2341
{ .name = "debug", .key = 128,
990
2438
delay = strtof(arg, &tmp);
991
2439
if(errno != 0 or tmp == arg or *tmp != '\0'){
992
fprintf(stderr, "Bad delay\n");
2440
argp_error(state, "Bad delay");
2442
case 132: /* --retry */
2444
retry_interval = strtod(arg, &tmp);
2445
if(errno != 0 or tmp == arg or *tmp != '\0'
2446
or (retry_interval * 1000) > INT_MAX
2447
or retry_interval < 0){
2448
argp_error(state, "Bad retry interval");
2451
case 133: /* --network-hook-dir */
2455
* These reproduce what we would get without ARGP_NO_HELP
2457
case '?': /* --help */
2458
argp_state_help(state, state->out_stream,
2459
(ARGP_HELP_STD_HELP | ARGP_HELP_EXIT_ERR)
2460
& ~(unsigned int)ARGP_HELP_EXIT_OK);
2461
case -3: /* --usage */
2462
argp_state_help(state, state->out_stream,
2463
ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);
2464
case 'V': /* --version */
2465
fprintf_plus(state->out_stream, "%s\n", argp_program_version);
2466
exit(argp_err_exit_status);
1001
2469
return ARGP_ERR_UNKNOWN;
1006
2474
struct argp argp = { .options = options, .parser = parse_opt,
1007
2475
.args_doc = "",
1008
2476
.doc = "Mandos client -- Get and decrypt"
1009
2477
" passwords from a Mandos server" };
1010
ret = argp_parse(&argp, argc, argv, 0, 0, NULL);
1011
if(ret == ARGP_ERR_UNKNOWN){
1012
fprintf(stderr, "Unknown error while parsing arguments\n");
1013
exitcode = EXIT_FAILURE;
2478
ret = argp_parse(&argp, argc, argv,
2479
ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);
2486
perror_plus("argp_parse");
2487
exitcode = EX_OSERR;
2490
exitcode = EX_USAGE;
2496
/* Work around Debian bug #633582:
2497
<http://bugs.debian.org/633582> */
2499
/* Re-raise privileges */
2500
ret_errno = raise_privileges();
2503
perror_plus("Failed to raise privileges");
2507
if(strcmp(seckey, PATHDIR "/" SECKEY) == 0){
2508
int seckey_fd = open(seckey, O_RDONLY);
2509
if(seckey_fd == -1){
2510
perror_plus("open");
2512
ret = (int)TEMP_FAILURE_RETRY(fstat(seckey_fd, &st));
2514
perror_plus("fstat");
2516
if(S_ISREG(st.st_mode)
2517
and st.st_uid == 0 and st.st_gid == 0){
2518
ret = fchown(seckey_fd, uid, gid);
2520
perror_plus("fchown");
2524
TEMP_FAILURE_RETRY(close(seckey_fd));
2528
if(strcmp(pubkey, PATHDIR "/" PUBKEY) == 0){
2529
int pubkey_fd = open(pubkey, O_RDONLY);
2530
if(pubkey_fd == -1){
2531
perror_plus("open");
2533
ret = (int)TEMP_FAILURE_RETRY(fstat(pubkey_fd, &st));
2535
perror_plus("fstat");
2537
if(S_ISREG(st.st_mode)
2538
and st.st_uid == 0 and st.st_gid == 0){
2539
ret = fchown(pubkey_fd, uid, gid);
2541
perror_plus("fchown");
2545
TEMP_FAILURE_RETRY(close(pubkey_fd));
2549
if(strcmp(dh_params_file, PATHDIR "/dhparams.pem" ) == 0){
2550
int dhparams_fd = open(dh_params_file, O_RDONLY);
2551
if(dhparams_fd == -1){
2552
perror_plus("open");
2554
ret = (int)TEMP_FAILURE_RETRY(fstat(dhparams_fd, &st));
2556
perror_plus("fstat");
2558
if(S_ISREG(st.st_mode)
2559
and st.st_uid == 0 and st.st_gid == 0){
2560
ret = fchown(dhparams_fd, uid, gid);
2562
perror_plus("fchown");
2566
TEMP_FAILURE_RETRY(close(dhparams_fd));
2570
/* Lower privileges */
2571
ret_errno = lower_privileges();
2574
perror_plus("Failed to lower privileges");
2579
/* Remove invalid interface names (except "none") */
2581
char *interface = NULL;
2582
while((interface = argz_next(mc.interfaces, mc.interfaces_size,
2584
if(strcmp(interface, "none") != 0
2585
and if_nametoindex(interface) == 0){
2586
if(interface[0] != '\0'){
2587
fprintf_plus(stderr, "Not using nonexisting interface"
2588
" \"%s\"\n", interface);
2590
argz_delete(&mc.interfaces, &mc.interfaces_size, interface);
2596
/* Run network hooks */
2598
if(mc.interfaces != NULL){
2599
interfaces_hooks = malloc(mc.interfaces_size);
2600
if(interfaces_hooks == NULL){
2601
perror_plus("malloc");
2604
memcpy(interfaces_hooks, mc.interfaces, mc.interfaces_size);
2605
argz_stringify(interfaces_hooks, mc.interfaces_size, (int)',');
2607
run_network_hooks("start", interfaces_hooks != NULL ?
2608
interfaces_hooks : "", delay);
1023
2616
from the signal handler */
1024
2617
/* Initialize the pseudo-RNG for Avahi */
1025
2618
srand((unsigned int) time(NULL));
1026
mc.simple_poll = avahi_simple_poll_new();
1027
if(mc.simple_poll == NULL){
1028
fprintf(stderr, "Avahi: Failed to create simple poll object.\n");
1029
exitcode = EXIT_FAILURE;
2619
simple_poll = avahi_simple_poll_new();
2620
if(simple_poll == NULL){
2621
fprintf_plus(stderr,
2622
"Avahi: Failed to create simple poll object.\n");
2623
exitcode = EX_UNAVAILABLE;
1033
2627
sigemptyset(&sigterm_action.sa_mask);
1034
2628
ret = sigaddset(&sigterm_action.sa_mask, SIGINT);
1036
perror("sigaddset");
1037
exitcode = EXIT_FAILURE;
2630
perror_plus("sigaddset");
2631
exitcode = EX_OSERR;
1040
2634
ret = sigaddset(&sigterm_action.sa_mask, SIGHUP);
1042
perror("sigaddset");
1043
exitcode = EXIT_FAILURE;
2636
perror_plus("sigaddset");
2637
exitcode = EX_OSERR;
1046
2640
ret = sigaddset(&sigterm_action.sa_mask, SIGTERM);
1048
perror("sigaddset");
1049
exitcode = EXIT_FAILURE;
1052
ret = sigaction(SIGTERM, &sigterm_action, &old_sigterm_action);
1054
perror("sigaction");
1055
exitcode = EXIT_FAILURE;
1059
/* If the interface is down, bring it up */
1060
if(interface[0] != '\0'){
1062
/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO
1063
messages to mess up the prompt */
1064
ret = klogctl(8, NULL, 5);
1065
bool restore_loglevel = true;
1067
restore_loglevel = false;
1070
#endif /* __linux__ */
1072
sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1075
exitcode = EXIT_FAILURE;
1077
if(restore_loglevel){
1078
ret = klogctl(7, NULL, 0);
1083
#endif /* __linux__ */
1086
strcpy(network.ifr_name, interface);
1087
ret = ioctl(sd, SIOCGIFFLAGS, &network);
1089
perror("ioctl SIOCGIFFLAGS");
1091
if(restore_loglevel){
1092
ret = klogctl(7, NULL, 0);
1097
#endif /* __linux__ */
1098
exitcode = EXIT_FAILURE;
1101
if((network.ifr_flags & IFF_UP) == 0){
1102
network.ifr_flags |= IFF_UP;
1103
ret = ioctl(sd, SIOCSIFFLAGS, &network);
1105
perror("ioctl SIOCSIFFLAGS");
1106
exitcode = EXIT_FAILURE;
1108
if(restore_loglevel){
1109
ret = klogctl(7, NULL, 0);
2642
perror_plus("sigaddset");
2643
exitcode = EX_OSERR;
2646
/* Need to check if the handler is SIG_IGN before handling:
2647
| [[info:libc:Initial Signal Actions]] |
2648
| [[info:libc:Basic Signal Handling]] |
2650
ret = sigaction(SIGINT, NULL, &old_sigterm_action);
2652
perror_plus("sigaction");
2655
if(old_sigterm_action.sa_handler != SIG_IGN){
2656
ret = sigaction(SIGINT, &sigterm_action, NULL);
2658
perror_plus("sigaction");
2659
exitcode = EX_OSERR;
2663
ret = sigaction(SIGHUP, NULL, &old_sigterm_action);
2665
perror_plus("sigaction");
2668
if(old_sigterm_action.sa_handler != SIG_IGN){
2669
ret = sigaction(SIGHUP, &sigterm_action, NULL);
2671
perror_plus("sigaction");
2672
exitcode = EX_OSERR;
2676
ret = sigaction(SIGTERM, NULL, &old_sigterm_action);
2678
perror_plus("sigaction");
2681
if(old_sigterm_action.sa_handler != SIG_IGN){
2682
ret = sigaction(SIGTERM, &sigterm_action, NULL);
2684
perror_plus("sigaction");
2685
exitcode = EX_OSERR;
2690
/* If no interfaces were specified, make a list */
2691
if(mc.interfaces == NULL){
2692
struct dirent **direntries = NULL;
2693
/* Look for any good interfaces */
2694
ret = scandir(sys_class_net, &direntries, good_interface,
2697
/* Add all found interfaces to interfaces list */
2698
for(int i = 0; i < ret; ++i){
2699
ret_errno = argz_add(&mc.interfaces, &mc.interfaces_size,
2700
direntries[i]->d_name);
2703
perror_plus("argz_add");
2704
free(direntries[i]);
2708
fprintf_plus(stderr, "Will use interface \"%s\"\n",
2709
direntries[i]->d_name);
2711
free(direntries[i]);
2718
fprintf_plus(stderr, "Could not find a network interface\n");
2719
exitcode = EXIT_FAILURE;
2724
/* Bring up interfaces which are down, and remove any "none"s */
2726
char *interface = NULL;
2727
while((interface = argz_next(mc.interfaces, mc.interfaces_size,
2729
/* If interface name is "none", stop bringing up interfaces.
2730
Also remove all instances of "none" from the list */
2731
if(strcmp(interface, "none") == 0){
2732
argz_delete(&mc.interfaces, &mc.interfaces_size,
2735
while((interface = argz_next(mc.interfaces,
2736
mc.interfaces_size, interface))){
2737
if(strcmp(interface, "none") == 0){
2738
argz_delete(&mc.interfaces, &mc.interfaces_size,
1114
#endif /* __linux__ */
1117
interface_taken_up = true;
1119
/* sleep checking until interface is running */
1120
for(int i=0; i < delay * 4; i++){
1121
ret = ioctl(sd, SIOCGIFFLAGS, &network);
1123
perror("ioctl SIOCGIFFLAGS");
1124
} else if(network.ifr_flags & IFF_RUNNING){
1127
struct timespec sleeptime = { .tv_nsec = 250000000 };
1128
ret = nanosleep(&sleeptime, NULL);
1129
if(ret == -1 and errno != EINTR){
1130
perror("nanosleep");
1133
if(not interface_taken_up){
1134
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1140
if(restore_loglevel){
1141
/* Restores kernel loglevel to default */
1142
ret = klogctl(7, NULL, 0);
1147
#endif /* __linux__ */
1164
ret = init_gnutls_global(pubkey, seckey);
1166
fprintf(stderr, "init_gnutls_global failed\n");
1167
exitcode = EXIT_FAILURE;
2745
bool interface_was_up = interface_is_up(interface);
2746
errno = bring_up_interface(interface, delay);
2747
if(not interface_was_up){
2749
fprintf_plus(stderr, "Failed to bring up interface \"%s\":"
2750
" %s\n", interface, strerror(errno));
2752
errno = argz_add(&interfaces_to_take_down,
2753
&interfaces_to_take_down_size,
2756
perror_plus("argz_add");
2761
if(debug and (interfaces_to_take_down == NULL)){
2762
fprintf_plus(stderr, "No interfaces were brought up\n");
2766
/* If we only got one interface, explicitly use only that one */
2767
if(argz_count(mc.interfaces, mc.interfaces_size) == 1){
2769
fprintf_plus(stderr, "Using only interface \"%s\"\n",
2772
if_index = (AvahiIfIndex)if_nametoindex(mc.interfaces);
2779
ret = init_gnutls_global(pubkey, seckey, dh_params_file, &mc);
2781
fprintf_plus(stderr, "init_gnutls_global failed\n");
2782
exitcode = EX_UNAVAILABLE;
1170
2785
gnutls_initialized = true;
1173
if(mkdtemp(tempdir) == NULL){
1177
tempdir_created = true;
1179
if(not init_gpgme(pubkey, seckey, tempdir)){
1180
fprintf(stderr, "init_gpgme failed\n");
1181
exitcode = EXIT_FAILURE;
2792
/* Try /run/tmp before /tmp */
2793
tempdir = mkdtemp(run_tempdir);
2794
if(tempdir == NULL and errno == ENOENT){
2796
fprintf_plus(stderr, "Tempdir %s did not work, trying %s\n",
2797
run_tempdir, old_tempdir);
2799
tempdir = mkdtemp(old_tempdir);
2801
if(tempdir == NULL){
2802
perror_plus("mkdtemp");
2810
if(not init_gpgme(pubkey, seckey, tempdir, &mc)){
2811
fprintf_plus(stderr, "init_gpgme failed\n");
2812
exitcode = EX_UNAVAILABLE;
1184
2815
gpgme_initialized = true;
1187
if(interface[0] != '\0'){
1188
if_index = (AvahiIfIndex) if_nametoindex(interface);
1190
fprintf(stderr, "No such interface: \"%s\"\n", interface);
1191
exitcode = EXIT_FAILURE;
1196
2822
if(connect_to != NULL){
1197
2823
/* Connect directly, do not use Zeroconf */
1198
2824
/* (Mainly meant for debugging) */
1199
2825
char *address = strrchr(connect_to, ':');
1200
2827
if(address == NULL){
1201
fprintf(stderr, "No colon in address\n");
1202
exitcode = EXIT_FAILURE;
2828
fprintf_plus(stderr, "No colon in address\n");
2829
exitcode = EX_USAGE;
1207
2839
tmpmax = strtoimax(address+1, &tmp, 10);
1208
2840
if(errno != 0 or tmp == address+1 or *tmp != '\0'
1209
or tmpmax != (uint16_t)tmpmax){
1210
fprintf(stderr, "Bad port number\n");
1211
exitcode = EXIT_FAILURE;
1214
port = (uint16_t)tmpmax;
2841
or tmpmax != (in_port_t)tmpmax){
2842
fprintf_plus(stderr, "Bad port number\n");
2843
exitcode = EX_USAGE;
2851
port = (in_port_t)tmpmax;
1215
2852
*address = '\0';
1216
address = connect_to;
1217
2853
/* Colon in address indicates IPv6 */
1219
if(strchr(address, ':') != NULL){
2855
if(strchr(connect_to, ':') != NULL){
2857
/* Accept [] around IPv6 address - see RFC 5952 */
2858
if(connect_to[0] == '[' and address[-1] == ']')
1224
ret = start_mandos_communication(address, port, if_index, af);
1226
exitcode = EXIT_FAILURE;
2866
address = connect_to;
2872
while(not quit_now){
2873
ret = start_mandos_communication(address, port, if_index, af,
2875
if(quit_now or ret == 0){
2879
fprintf_plus(stderr, "Retrying in %d seconds\n",
2880
(int)retry_interval);
2882
sleep((unsigned int)retry_interval);
1228
2886
exitcode = EXIT_SUCCESS;
1234
2897
AvahiServerConfig config;
1235
2898
/* Do not publish any local Zeroconf records */
1301
2979
gpgme_release(mc.ctx);
1304
/* Take down the network interface */
1305
if(interface_taken_up){
1306
ret = ioctl(sd, SIOCGIFFLAGS, &network);
1308
perror("ioctl SIOCGIFFLAGS");
1309
} else if(network.ifr_flags & IFF_UP) {
1310
network.ifr_flags &= ~IFF_UP; /* clear flag */
1311
ret = ioctl(sd, SIOCSIFFLAGS, &network);
1313
perror("ioctl SIOCSIFFLAGS");
1316
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1322
/* Removes the temp directory used by GPGME */
1323
if(tempdir_created){
1325
struct dirent *direntry;
1326
d = opendir(tempdir);
1328
if(errno != ENOENT){
1333
direntry = readdir(d);
1334
if(direntry == NULL){
1337
/* Skip "." and ".." */
1338
if(direntry->d_name[0] == '.'
1339
and (direntry->d_name[1] == '\0'
1340
or (direntry->d_name[1] == '.'
1341
and direntry->d_name[2] == '\0'))){
1344
char *fullname = NULL;
1345
ret = asprintf(&fullname, "%s/%s", tempdir,
1351
ret = remove(fullname);
1353
fprintf(stderr, "remove(\"%s\"): %s\n", fullname,
1360
ret = rmdir(tempdir);
1361
if(ret == -1 and errno != ENOENT){
2982
/* Cleans up the circular linked list of Mandos servers the client
2984
if(mc.current_server != NULL){
2985
mc.current_server->prev->next = NULL;
2986
while(mc.current_server != NULL){
2987
server *next = mc.current_server->next;
2989
#pragma GCC diagnostic push
2990
#pragma GCC diagnostic ignored "-Wcast-qual"
2992
free((char *)(mc.current_server->ip));
2994
#pragma GCC diagnostic pop
2996
free(mc.current_server);
2997
mc.current_server = next;
3001
/* Re-raise privileges */
3003
ret_errno = raise_privileges();
3006
perror_plus("Failed to raise privileges");
3009
/* Run network hooks */
3010
run_network_hooks("stop", interfaces_hooks != NULL ?
3011
interfaces_hooks : "", delay);
3013
/* Take down the network interfaces which were brought up */
3015
char *interface = NULL;
3016
while((interface=argz_next(interfaces_to_take_down,
3017
interfaces_to_take_down_size,
3019
ret_errno = take_down_interface(interface);
3022
perror_plus("Failed to take down interface");
3025
if(debug and (interfaces_to_take_down == NULL)){
3026
fprintf_plus(stderr, "No interfaces needed to be taken"
3032
ret_errno = lower_privileges_permanently();
3035
perror_plus("Failed to lower privileges permanently");
3039
free(interfaces_to_take_down);
3040
free(interfaces_hooks);
3042
/* Removes the GPGME temp directory and all files inside */
3043
if(tempdir != NULL){
3044
struct dirent **direntries = NULL;
3045
int tempdir_fd = (int)TEMP_FAILURE_RETRY(open(tempdir, O_RDONLY
3049
if(tempdir_fd == -1){
3050
perror_plus("open");
3053
#if __GLIBC_PREREQ(2, 15)
3054
int numentries = scandirat(tempdir_fd, ".", &direntries,
3055
notdotentries, alphasort);
3056
#else /* not __GLIBC_PREREQ(2, 15) */
3057
int numentries = scandir(tempdir, &direntries, notdotentries,
3059
#endif /* not __GLIBC_PREREQ(2, 15) */
3060
#else /* not __GLIBC__ */
3061
int numentries = scandir(tempdir, &direntries, notdotentries,
3063
#endif /* not __GLIBC__ */
3064
if(numentries >= 0){
3065
for(int i = 0; i < numentries; i++){
3066
ret = unlinkat(tempdir_fd, direntries[i]->d_name, 0);
3068
fprintf_plus(stderr, "unlinkat(open(\"%s\", O_RDONLY),"
3069
" \"%s\", 0): %s\n", tempdir,
3070
direntries[i]->d_name, strerror(errno));
3072
free(direntries[i]);
3075
/* need to clean even if 0 because man page doesn't specify */
3077
if(numentries == -1){
3078
perror_plus("scandir");
3080
ret = rmdir(tempdir);
3081
if(ret == -1 and errno != ENOENT){
3082
perror_plus("rmdir");
3085
TEMP_FAILURE_RETRY(close(tempdir_fd));
3090
sigemptyset(&old_sigterm_action.sa_mask);
3091
old_sigterm_action.sa_handler = SIG_DFL;
3092
ret = (int)TEMP_FAILURE_RETRY(sigaction(signal_received,
3093
&old_sigterm_action,
3096
perror_plus("sigaction");
3099
ret = raise(signal_received);
3100
} while(ret != 0 and errno == EINTR);
3102
perror_plus("raise");
3105
TEMP_FAILURE_RETRY(pause());
1366
3108
return exitcode;