26
26
* along with this program. If not, see
27
27
* <http://www.gnu.org/licenses/>.
29
* Contact the authors at <mandos@fukt.bsnet.se>.
29
* Contact the authors at <mandos@recompile.se>.
32
32
/* Needed by GPGME, specifically gpgme_data_seek() */
33
33
#ifndef _LARGEFILE_SOURCE
34
34
#define _LARGEFILE_SOURCE
35
#endif /* not _LARGEFILE_SOURCE */
36
36
#ifndef _FILE_OFFSET_BITS
37
37
#define _FILE_OFFSET_BITS 64
38
#endif /* not _FILE_OFFSET_BITS */
40
40
#define _GNU_SOURCE /* TEMP_FAILURE_RETRY(), asprintf() */
42
42
#include <stdio.h> /* fprintf(), stderr, fwrite(),
43
stdout, ferror(), remove() */
44
#include <stdint.h> /* uint16_t, uint32_t */
44
#include <stdint.h> /* uint16_t, uint32_t, intptr_t */
45
45
#include <stddef.h> /* NULL, size_t, ssize_t */
46
46
#include <stdlib.h> /* free(), EXIT_SUCCESS, srand(),
47
47
strtof(), abort() */
48
48
#include <stdbool.h> /* bool, false, true */
49
#include <string.h> /* memset(), strcmp(), strlen(),
50
strerror(), asprintf(), strcpy() */
49
#include <string.h> /* strcmp(), strlen(), strerror(),
50
asprintf(), strncpy() */
51
51
#include <sys/ioctl.h> /* ioctl */
52
52
#include <sys/types.h> /* socket(), inet_pton(), sockaddr,
53
53
sockaddr_in6, PF_INET6,
54
54
SOCK_STREAM, uid_t, gid_t, open(),
56
#include <sys/stat.h> /* open() */
56
#include <sys/stat.h> /* open(), S_ISREG */
57
57
#include <sys/socket.h> /* socket(), struct sockaddr_in6,
58
inet_pton(), connect() */
59
#include <fcntl.h> /* open() */
58
inet_pton(), connect(),
60
#include <fcntl.h> /* open(), unlinkat(), AT_REMOVEDIR */
60
61
#include <dirent.h> /* opendir(), struct dirent, readdir()
62
63
#include <inttypes.h> /* PRIu16, PRIdMAX, intmax_t,
64
#include <assert.h> /* assert() */
65
#include <errno.h> /* perror(), errno,
65
#include <errno.h> /* perror(), errno, EINTR, EINVAL,
66
EAI_SYSTEM, ENETUNREACH,
67
EHOSTUNREACH, ECONNREFUSED, EPROTO,
68
EIO, ENOENT, ENXIO, ENOMEM, EISDIR,
66
70
program_invocation_short_name */
67
71
#include <time.h> /* nanosleep(), time(), sleep() */
68
72
#include <net/if.h> /* ioctl, ifreq, SIOCGIFFLAGS, IFF_UP,
152
170
const char *priority;
154
172
server *current_server;
174
size_t interfaces_size;
155
175
} mandos_context;
157
/* global context so signal handler can reach it*/
158
mandos_context mc = { .simple_poll = NULL, .server = NULL,
159
.dh_bits = 1024, .priority = "SECURE256"
160
":!CTYPE-X.509:+CTYPE-OPENPGP",
161
.current_server = NULL };
177
/* global so signal handler can reach it*/
178
AvahiSimplePoll *simple_poll;
163
180
sig_atomic_t quit_now = 0;
164
181
int signal_received = 0;
166
183
/* Function to use when printing errors */
167
184
void perror_plus(const char *print_text){
168
186
fprintf(stderr, "Mandos plugin %s: ",
169
187
program_invocation_short_name);
170
189
perror(print_text);
192
__attribute__((format (gnu_printf, 2, 3), nonnull))
193
int fprintf_plus(FILE *stream, const char *format, ...){
195
va_start (ap, format);
197
TEMP_FAILURE_RETRY(fprintf(stream, "Mandos plugin %s: ",
198
program_invocation_short_name));
199
return (int)TEMP_FAILURE_RETRY(vfprintf(stream, format, ap));
174
203
* Make additional room in "buffer" for at least BUFFER_SIZE more
175
204
* bytes. "buffer_capacity" is how much is currently allocated,
176
205
* "buffer_length" is how much is already used.
207
__attribute__((nonnull, warn_unused_result))
178
208
size_t incbuffer(char **buffer, size_t buffer_length,
179
size_t buffer_capacity){
209
size_t buffer_capacity){
180
210
if(buffer_length + BUFFER_SIZE > buffer_capacity){
181
*buffer = realloc(*buffer, buffer_capacity + BUFFER_SIZE);
211
char *new_buf = realloc(*buffer, buffer_capacity + BUFFER_SIZE);
213
int old_errno = errno;
185
220
buffer_capacity += BUFFER_SIZE;
187
222
return buffer_capacity;
190
int add_server(const char *ip, uint16_t port,
191
AvahiIfIndex if_index,
225
/* Add server to set of servers to retry periodically */
226
__attribute__((nonnull, warn_unused_result))
227
bool add_server(const char *ip, in_port_t port, AvahiIfIndex if_index,
228
int af, server **current_server){
194
230
server *new_server = malloc(sizeof(server));
195
231
if(new_server == NULL){
196
232
perror_plus("malloc");
199
235
*new_server = (server){ .ip = strdup(ip),
201
.if_index = if_index,
237
.if_index = if_index,
203
239
if(new_server->ip == NULL){
204
240
perror_plus("strdup");
207
/* unique case of first server */
208
if (mc.current_server == NULL){
244
ret = clock_gettime(CLOCK_MONOTONIC, &(new_server->last_seen));
246
perror_plus("clock_gettime");
248
#pragma GCC diagnostic push
249
#pragma GCC diagnostic ignored "-Wcast-qual"
251
free((char *)(new_server->ip));
253
#pragma GCC diagnostic pop
258
/* Special case of first server */
259
if(*current_server == NULL){
209
260
new_server->next = new_server;
210
261
new_server->prev = new_server;
211
mc.current_server = new_server;
212
/* Placing the new server last in the list */
262
*current_server = new_server;
214
new_server->next = mc.current_server;
215
new_server->prev = mc.current_server->prev;
264
/* Place the new server last in the list */
265
new_server->next = *current_server;
266
new_server->prev = (*current_server)->prev;
216
267
new_server->prev->next = new_server;
217
mc.current_server->prev = new_server;
219
ret = clock_gettime(CLOCK_MONOTONIC, &mc.current_server->last_seen);
221
perror_plus("clock_gettime");
268
(*current_server)->prev = new_server;
228
274
* Initialize GPGME.
230
static bool init_gpgme(const char *seckey,
231
const char *pubkey, const char *tempdir){
276
__attribute__((nonnull, warn_unused_result))
277
static bool init_gpgme(const char * const seckey,
278
const char * const pubkey,
279
const char * const tempdir,
232
281
gpgme_error_t rc;
233
282
gpgme_engine_info_t engine_info;
237
285
* Helper function to insert pub and seckey to the engine keyring.
239
bool import_key(const char *filename){
287
bool import_key(const char * const filename){
242
290
gpgme_data_t pgp_data;
331
383
ssize_t plaintext_length = 0;
334
fprintf(stderr, "Trying to decrypt OpenPGP data\n");
386
fprintf_plus(stderr, "Trying to decrypt OpenPGP data\n");
337
389
/* Create new GPGME data buffer from memory cryptotext */
338
390
rc = gpgme_data_new_from_mem(&dh_crypto, cryptotext, crypto_size,
340
392
if(rc != GPG_ERR_NO_ERROR){
341
fprintf(stderr, "bad gpgme_data_new_from_mem: %s: %s\n",
342
gpgme_strsource(rc), gpgme_strerror(rc));
393
fprintf_plus(stderr, "bad gpgme_data_new_from_mem: %s: %s\n",
394
gpgme_strsource(rc), gpgme_strerror(rc));
346
398
/* Create new empty GPGME data buffer for the plaintext */
347
399
rc = gpgme_data_new(&dh_plain);
348
400
if(rc != GPG_ERR_NO_ERROR){
349
fprintf(stderr, "bad gpgme_data_new: %s: %s\n",
350
gpgme_strsource(rc), gpgme_strerror(rc));
401
fprintf_plus(stderr, "Mandos plugin mandos-client: "
402
"bad gpgme_data_new: %s: %s\n",
403
gpgme_strsource(rc), gpgme_strerror(rc));
351
404
gpgme_data_release(dh_crypto);
355
408
/* Decrypt data from the cryptotext data buffer to the plaintext
357
rc = gpgme_op_decrypt(mc.ctx, dh_crypto, dh_plain);
410
rc = gpgme_op_decrypt(mc->ctx, dh_crypto, dh_plain);
358
411
if(rc != GPG_ERR_NO_ERROR){
359
fprintf(stderr, "bad gpgme_op_decrypt: %s: %s\n",
360
gpgme_strsource(rc), gpgme_strerror(rc));
412
fprintf_plus(stderr, "bad gpgme_op_decrypt: %s: %s\n",
413
gpgme_strsource(rc), gpgme_strerror(rc));
361
414
plaintext_length = -1;
363
416
gpgme_decrypt_result_t result;
364
result = gpgme_op_decrypt_result(mc.ctx);
417
result = gpgme_op_decrypt_result(mc->ctx);
365
418
if(result == NULL){
366
fprintf(stderr, "gpgme_op_decrypt_result failed\n");
419
fprintf_plus(stderr, "gpgme_op_decrypt_result failed\n");
368
fprintf(stderr, "Unsupported algorithm: %s\n",
369
result->unsupported_algorithm);
370
fprintf(stderr, "Wrong key usage: %u\n",
371
result->wrong_key_usage);
421
fprintf_plus(stderr, "Unsupported algorithm: %s\n",
422
result->unsupported_algorithm);
423
fprintf_plus(stderr, "Wrong key usage: %u\n",
424
result->wrong_key_usage);
372
425
if(result->file_name != NULL){
373
fprintf(stderr, "File name: %s\n", result->file_name);
426
fprintf_plus(stderr, "File name: %s\n", result->file_name);
375
428
gpgme_recipient_t recipient;
376
429
recipient = result->recipients;
377
430
while(recipient != NULL){
378
fprintf(stderr, "Public key algorithm: %s\n",
379
gpgme_pubkey_algo_name(recipient->pubkey_algo));
380
fprintf(stderr, "Key ID: %s\n", recipient->keyid);
381
fprintf(stderr, "Secret key available: %s\n",
382
recipient->status == GPG_ERR_NO_SECKEY
431
fprintf_plus(stderr, "Public key algorithm: %s\n",
432
gpgme_pubkey_algo_name
433
(recipient->pubkey_algo));
434
fprintf_plus(stderr, "Key ID: %s\n", recipient->keyid);
435
fprintf_plus(stderr, "Secret key available: %s\n",
436
recipient->status == GPG_ERR_NO_SECKEY
384
438
recipient = recipient->next;
443
497
return plaintext_length;
446
static const char * safer_gnutls_strerror(int value){
447
const char *ret = gnutls_strerror(value); /* Spurious warning from
448
-Wunreachable-code */
500
__attribute__((warn_unused_result, const))
501
static const char *safe_string(const char *str){
507
__attribute__((warn_unused_result))
508
static const char *safer_gnutls_strerror(int value){
509
const char *ret = gnutls_strerror(value);
510
return safe_string(ret);
454
513
/* GnuTLS log function callback */
514
__attribute__((nonnull))
455
515
static void debuggnutls(__attribute__((unused)) int level,
456
516
const char* string){
457
fprintf(stderr, "GnuTLS: %s", string);
517
fprintf_plus(stderr, "GnuTLS: %s", string);
520
__attribute__((nonnull(1, 2, 4), warn_unused_result))
460
521
static int init_gnutls_global(const char *pubkeyfilename,
461
const char *seckeyfilename){
522
const char *seckeyfilename,
523
const char *dhparamsfilename,
465
fprintf(stderr, "Initializing GnuTLS\n");
468
ret = gnutls_global_init();
469
if(ret != GNUTLS_E_SUCCESS){
470
fprintf(stderr, "GnuTLS global_init: %s\n",
471
safer_gnutls_strerror(ret));
529
fprintf_plus(stderr, "Initializing GnuTLS\n");
483
540
/* OpenPGP credentials */
484
ret = gnutls_certificate_allocate_credentials(&mc.cred);
541
ret = gnutls_certificate_allocate_credentials(&mc->cred);
485
542
if(ret != GNUTLS_E_SUCCESS){
486
fprintf(stderr, "GnuTLS memory error: %s\n",
487
safer_gnutls_strerror(ret));
488
gnutls_global_deinit();
543
fprintf_plus(stderr, "GnuTLS memory error: %s\n",
544
safer_gnutls_strerror(ret));
493
fprintf(stderr, "Attempting to use OpenPGP public key %s and"
494
" secret key %s as GnuTLS credentials\n", pubkeyfilename,
549
fprintf_plus(stderr, "Attempting to use OpenPGP public key %s and"
550
" secret key %s as GnuTLS credentials\n",
498
555
ret = gnutls_certificate_set_openpgp_key_file
499
(mc.cred, pubkeyfilename, seckeyfilename,
556
(mc->cred, pubkeyfilename, seckeyfilename,
500
557
GNUTLS_OPENPGP_FMT_BASE64);
501
558
if(ret != GNUTLS_E_SUCCESS){
503
"Error[%d] while reading the OpenPGP key pair ('%s',"
504
" '%s')\n", ret, pubkeyfilename, seckeyfilename);
505
fprintf(stderr, "The GnuTLS error is: %s\n",
506
safer_gnutls_strerror(ret));
560
"Error[%d] while reading the OpenPGP key pair ('%s',"
561
" '%s')\n", ret, pubkeyfilename, seckeyfilename);
562
fprintf_plus(stderr, "The GnuTLS error is: %s\n",
563
safer_gnutls_strerror(ret));
510
567
/* GnuTLS server initialization */
511
ret = gnutls_dh_params_init(&mc.dh_params);
512
if(ret != GNUTLS_E_SUCCESS){
513
fprintf(stderr, "Error in GnuTLS DH parameter initialization:"
514
" %s\n", safer_gnutls_strerror(ret));
517
ret = gnutls_dh_params_generate2(mc.dh_params, mc.dh_bits);
518
if(ret != GNUTLS_E_SUCCESS){
519
fprintf(stderr, "Error in GnuTLS prime generation: %s\n",
520
safer_gnutls_strerror(ret));
524
gnutls_certificate_set_dh_params(mc.cred, mc.dh_params);
568
ret = gnutls_dh_params_init(&mc->dh_params);
569
if(ret != GNUTLS_E_SUCCESS){
570
fprintf_plus(stderr, "Error in GnuTLS DH parameter"
571
" initialization: %s\n",
572
safer_gnutls_strerror(ret));
575
/* If a Diffie-Hellman parameters file was given, try to use it */
576
if(dhparamsfilename != NULL){
577
gnutls_datum_t params = { .data = NULL, .size = 0 };
579
int dhpfile = open(dhparamsfilename, O_RDONLY);
582
dhparamsfilename = NULL;
585
size_t params_capacity = 0;
587
params_capacity = incbuffer((char **)¶ms.data,
589
(size_t)params_capacity);
590
if(params_capacity == 0){
591
perror_plus("incbuffer");
594
dhparamsfilename = NULL;
597
ssize_t bytes_read = read(dhpfile,
598
params.data + params.size,
604
/* check bytes_read for failure */
609
dhparamsfilename = NULL;
612
params.size += (unsigned int)bytes_read;
614
if(params.data == NULL){
615
dhparamsfilename = NULL;
617
if(dhparamsfilename == NULL){
620
ret = gnutls_dh_params_import_pkcs3(mc->dh_params, ¶ms,
621
GNUTLS_X509_FMT_PEM);
622
if(ret != GNUTLS_E_SUCCESS){
623
fprintf_plus(stderr, "Failed to parse DH parameters in file"
624
" \"%s\": %s\n", dhparamsfilename,
625
safer_gnutls_strerror(ret));
626
dhparamsfilename = NULL;
630
if(dhparamsfilename == NULL){
631
if(mc->dh_bits == 0){
632
/* Find out the optimal number of DH bits */
633
/* Try to read the private key file */
634
gnutls_datum_t buffer = { .data = NULL, .size = 0 };
636
int secfile = open(seckeyfilename, O_RDONLY);
641
size_t buffer_capacity = 0;
643
buffer_capacity = incbuffer((char **)&buffer.data,
645
(size_t)buffer_capacity);
646
if(buffer_capacity == 0){
647
perror_plus("incbuffer");
652
ssize_t bytes_read = read(secfile,
653
buffer.data + buffer.size,
659
/* check bytes_read for failure */
666
buffer.size += (unsigned int)bytes_read;
670
/* If successful, use buffer to parse private key */
671
gnutls_sec_param_t sec_param = GNUTLS_SEC_PARAM_ULTRA;
672
if(buffer.data != NULL){
674
gnutls_openpgp_privkey_t privkey = NULL;
675
ret = gnutls_openpgp_privkey_init(&privkey);
676
if(ret != GNUTLS_E_SUCCESS){
677
fprintf_plus(stderr, "Error initializing OpenPGP key"
679
safer_gnutls_strerror(ret));
683
ret = gnutls_openpgp_privkey_import
684
(privkey, &buffer, GNUTLS_OPENPGP_FMT_BASE64, "", 0);
685
if(ret != GNUTLS_E_SUCCESS){
686
fprintf_plus(stderr, "Error importing OpenPGP key : %s",
687
safer_gnutls_strerror(ret));
693
/* Use private key to suggest an appropriate
695
sec_param = gnutls_openpgp_privkey_sec_param(privkey);
696
gnutls_openpgp_privkey_deinit(privkey);
698
fprintf_plus(stderr, "This OpenPGP key implies using"
699
" a GnuTLS security parameter \"%s\".\n",
700
safe_string(gnutls_sec_param_get_name
706
if(sec_param == GNUTLS_SEC_PARAM_UNKNOWN){
707
/* Err on the side of caution */
708
sec_param = GNUTLS_SEC_PARAM_ULTRA;
710
fprintf_plus(stderr, "Falling back to security parameter"
712
safe_string(gnutls_sec_param_get_name
717
uret = gnutls_sec_param_to_pk_bits(GNUTLS_PK_DH, sec_param);
721
fprintf_plus(stderr, "A \"%s\" GnuTLS security parameter"
722
" implies %u DH bits; using that.\n",
723
safe_string(gnutls_sec_param_get_name
728
fprintf_plus(stderr, "Failed to get implied number of DH"
729
" bits for security parameter \"%s\"): %s\n",
730
safe_string(gnutls_sec_param_get_name
732
safer_gnutls_strerror(ret));
736
fprintf_plus(stderr, "DH bits explicitly set to %u\n",
739
ret = gnutls_dh_params_generate2(mc->dh_params, mc->dh_bits);
740
if(ret != GNUTLS_E_SUCCESS){
741
fprintf_plus(stderr, "Error in GnuTLS prime generation (%u"
742
" bits): %s\n", mc->dh_bits,
743
safer_gnutls_strerror(ret));
747
gnutls_certificate_set_dh_params(mc->cred, mc->dh_params);
530
gnutls_certificate_free_credentials(mc.cred);
531
gnutls_global_deinit();
532
gnutls_dh_params_deinit(mc.dh_params);
753
gnutls_certificate_free_credentials(mc->cred);
754
gnutls_dh_params_deinit(mc->dh_params);
536
static int init_gnutls_session(gnutls_session_t *session){
758
__attribute__((nonnull, warn_unused_result))
759
static int init_gnutls_session(gnutls_session_t *session,
538
762
/* GnuTLS session creation */
592
815
static void empty_log(__attribute__((unused)) AvahiLogLevel level,
593
816
__attribute__((unused)) const char *txt){}
818
/* Set effective uid to 0, return errno */
819
__attribute__((warn_unused_result))
820
error_t raise_privileges(void){
821
error_t old_errno = errno;
822
error_t ret_errno = 0;
823
if(seteuid(0) == -1){
830
/* Set effective and real user ID to 0. Return errno. */
831
__attribute__((warn_unused_result))
832
error_t raise_privileges_permanently(void){
833
error_t old_errno = errno;
834
error_t ret_errno = raise_privileges();
846
/* Set effective user ID to unprivileged saved user ID */
847
__attribute__((warn_unused_result))
848
error_t lower_privileges(void){
849
error_t old_errno = errno;
850
error_t ret_errno = 0;
851
if(seteuid(uid) == -1){
858
/* Lower privileges permanently */
859
__attribute__((warn_unused_result))
860
error_t lower_privileges_permanently(void){
861
error_t old_errno = errno;
862
error_t ret_errno = 0;
863
if(setuid(uid) == -1){
870
/* Helper function to add_local_route() and delete_local_route() */
871
__attribute__((nonnull, warn_unused_result))
872
static bool add_delete_local_route(const bool add,
874
AvahiIfIndex if_index){
876
char helper[] = "mandos-client-iprouteadddel";
877
char add_arg[] = "add";
878
char delete_arg[] = "delete";
879
char debug_flag[] = "--debug";
880
char *pluginhelperdir = getenv("MANDOSPLUGINHELPERDIR");
881
if(pluginhelperdir == NULL){
883
fprintf_plus(stderr, "MANDOSPLUGINHELPERDIR environment"
884
" variable not set; cannot run helper\n");
889
char interface[IF_NAMESIZE];
890
if(if_indextoname((unsigned int)if_index, interface) == NULL){
891
perror_plus("if_indextoname");
895
int devnull = (int)TEMP_FAILURE_RETRY(open("/dev/null", O_RDONLY));
897
perror_plus("open(\"/dev/null\", O_RDONLY)");
903
/* Raise privileges */
904
errno = raise_privileges_permanently();
906
perror_plus("Failed to raise privileges");
907
/* _exit(EX_NOPERM); */
913
perror_plus("setgid");
916
/* Reset supplementary groups */
918
ret = setgroups(0, NULL);
920
perror_plus("setgroups");
924
ret = dup2(devnull, STDIN_FILENO);
926
perror_plus("dup2(devnull, STDIN_FILENO)");
929
ret = close(devnull);
931
perror_plus("close");
934
ret = dup2(STDERR_FILENO, STDOUT_FILENO);
936
perror_plus("dup2(STDERR_FILENO, STDOUT_FILENO)");
939
int helperdir_fd = (int)TEMP_FAILURE_RETRY(open(pluginhelperdir,
944
if(helperdir_fd == -1){
946
_exit(EX_UNAVAILABLE);
948
int helper_fd = (int)TEMP_FAILURE_RETRY(openat(helperdir_fd,
951
perror_plus("openat");
953
_exit(EX_UNAVAILABLE);
957
#pragma GCC diagnostic push
958
#pragma GCC diagnostic ignored "-Wcast-qual"
960
if(fexecve(helper_fd, (char *const [])
961
{ helper, add ? add_arg : delete_arg, (char *)address,
962
interface, debug ? debug_flag : NULL, NULL },
965
#pragma GCC diagnostic pop
967
perror_plus("fexecve");
979
pret = waitpid(pid, &status, 0);
980
if(pret == -1 and errno == EINTR and quit_now){
981
int errno_raising = 0;
982
if((errno = raise_privileges()) != 0){
983
errno_raising = errno;
984
perror_plus("Failed to raise privileges in order to"
985
" kill helper program");
987
if(kill(pid, SIGTERM) == -1){
990
if((errno_raising == 0) and (errno = lower_privileges()) != 0){
991
perror_plus("Failed to lower privileges after killing"
996
} while(pret == -1 and errno == EINTR);
998
perror_plus("waitpid");
1001
if(WIFEXITED(status)){
1002
if(WEXITSTATUS(status) != 0){
1003
fprintf_plus(stderr, "Error: iprouteadddel exited"
1004
" with status %d\n", WEXITSTATUS(status));
1009
if(WIFSIGNALED(status)){
1010
fprintf_plus(stderr, "Error: iprouteadddel died by"
1011
" signal %d\n", WTERMSIG(status));
1014
fprintf_plus(stderr, "Error: iprouteadddel crashed\n");
1018
__attribute__((nonnull, warn_unused_result))
1019
static bool add_local_route(const char *address,
1020
AvahiIfIndex if_index){
1022
fprintf_plus(stderr, "Adding route to %s\n", address);
1024
return add_delete_local_route(true, address, if_index);
1027
__attribute__((nonnull, warn_unused_result))
1028
static bool delete_local_route(const char *address,
1029
AvahiIfIndex if_index){
1031
fprintf_plus(stderr, "Removing route to %s\n", address);
1033
return add_delete_local_route(false, address, if_index);
595
1036
/* Called when a Mandos server is found */
596
static int start_mandos_communication(const char *ip, uint16_t port,
1037
__attribute__((nonnull, warn_unused_result))
1038
static int start_mandos_communication(const char *ip, in_port_t port,
597
1039
AvahiIfIndex if_index,
1040
int af, mandos_context *mc){
599
1041
int ret, tcp_sd = -1;
602
struct sockaddr_in in;
603
struct sockaddr_in6 in6;
1043
struct sockaddr_storage to;
605
1044
char *buffer = NULL;
606
1045
char *decrypted_buffer = NULL;
607
1046
size_t buffer_length = 0;
629
fprintf(stderr, "Bad address family: %d\n", af);
1069
fprintf_plus(stderr, "Bad address family: %d\n", af);
634
ret = init_gnutls_session(&session);
1074
/* If the interface is specified and we have a list of interfaces */
1075
if(if_index != AVAHI_IF_UNSPEC and mc->interfaces != NULL){
1076
/* Check if the interface is one of the interfaces we are using */
1079
char *interface = NULL;
1080
while((interface=argz_next(mc->interfaces, mc->interfaces_size,
1082
if(if_nametoindex(interface) == (unsigned int)if_index){
1089
/* This interface does not match any in the list, so we don't
1090
connect to the server */
1092
char interface[IF_NAMESIZE];
1093
if(if_indextoname((unsigned int)if_index, interface) == NULL){
1094
perror_plus("if_indextoname");
1096
fprintf_plus(stderr, "Skipping server on non-used interface"
1098
if_indextoname((unsigned int)if_index,
1106
ret = init_gnutls_session(&session, mc);
640
fprintf(stderr, "Setting up a TCP connection to %s, port %" PRIu16
1112
fprintf_plus(stderr, "Setting up a TCP connection to %s, port %"
1113
PRIuMAX "\n", ip, (uintmax_t)port);
644
tcp_sd = socket(pf, SOCK_STREAM, 0);
1116
tcp_sd = socket(pf, SOCK_STREAM | SOCK_CLOEXEC, 0);
647
1119
perror_plus("socket");
708
1175
if(if_indextoname((unsigned int)if_index, interface) == NULL){
709
1176
perror_plus("if_indextoname");
711
fprintf(stderr, "Connection to: %s%%%s, port %" PRIu16 "\n",
712
ip, interface, port);
1178
fprintf_plus(stderr, "Connection to: %s%%%s, port %" PRIuMAX
1179
"\n", ip, interface, (uintmax_t)port);
715
fprintf(stderr, "Connection to: %s, port %" PRIu16 "\n", ip,
1182
fprintf_plus(stderr, "Connection to: %s, port %" PRIuMAX "\n",
1183
ip, (uintmax_t)port);
718
1185
char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?
719
1186
INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";
722
pcret = inet_ntop(af, &(to.in6.sin6_addr), addrstr,
725
pcret = inet_ntop(af, &(to.in.sin_addr), addrstr,
729
perror_plus("inet_ntop");
731
if(strcmp(addrstr, ip) != 0){
732
fprintf(stderr, "Canonical address form: %s\n", addrstr);
743
ret = connect(tcp_sd, &to.in6, sizeof(to));
745
ret = connect(tcp_sd, &to.in, sizeof(to)); /* IPv4 */
748
if ((errno != ECONNREFUSED and errno != ENETUNREACH) or debug){
750
perror_plus("connect");
1188
ret = getnameinfo((struct sockaddr *)&to,
1189
sizeof(struct sockaddr_in6),
1190
addrstr, sizeof(addrstr), NULL, 0,
1193
ret = getnameinfo((struct sockaddr *)&to,
1194
sizeof(struct sockaddr_in),
1195
addrstr, sizeof(addrstr), NULL, 0,
1198
if(ret == EAI_SYSTEM){
1199
perror_plus("getnameinfo");
1200
} else if(ret != 0) {
1201
fprintf_plus(stderr, "getnameinfo: %s", gai_strerror(ret));
1202
} else if(strcmp(addrstr, ip) != 0){
1203
fprintf_plus(stderr, "Canonical address form: %s\n", addrstr);
1214
ret = connect(tcp_sd, (struct sockaddr *)&to,
1215
sizeof(struct sockaddr_in6));
1217
ret = connect(tcp_sd, (struct sockaddr *)&to, /* IPv4 */
1218
sizeof(struct sockaddr_in));
1221
if(((errno == ENETUNREACH) or (errno == EHOSTUNREACH))
1222
and if_index != AVAHI_IF_UNSPEC
1223
and connect_to == NULL
1224
and not route_added and
1225
((af == AF_INET6 and not
1226
IN6_IS_ADDR_LINKLOCAL(&(((struct sockaddr_in6 *)
1228
or (af == AF_INET and
1229
/* Not a a IPv4LL address */
1230
(ntohl(((struct sockaddr_in *)&to)->sin_addr.s_addr)
1231
& 0xFFFF0000L) != 0xA9FE0000L))){
1232
/* Work around Avahi bug - Avahi does not announce link-local
1233
addresses if it has a global address, so local hosts with
1234
*only* a link-local address (e.g. Mandos clients) cannot
1235
connect to a Mandos server announced by Avahi on a server
1236
host with a global address. Work around this by retrying
1237
with an explicit route added with the server's address.
1239
Avahi bug reference:
1240
http://lists.freedesktop.org/archives/avahi/2010-February/001833.html
1241
https://bugs.debian.org/587961
1244
fprintf_plus(stderr, "Mandos server unreachable, trying"
1248
route_added = add_local_route(ip, if_index);
1254
if(errno != ECONNREFUSED or debug){
1256
perror_plus("connect");
761
1269
const char *out = mandos_protocol_version;
999
1522
char ip[AVAHI_ADDRESS_STR_MAX];
1000
1523
avahi_address_snprint(ip, sizeof(ip), address);
1002
fprintf(stderr, "Mandos server \"%s\" found on %s (%s, %"
1003
PRIdMAX ") on port %" PRIu16 "\n", name, host_name,
1004
ip, (intmax_t)interface, port);
1525
fprintf_plus(stderr, "Mandos server \"%s\" found on %s (%s, %"
1526
PRIdMAX ") on port %" PRIu16 "\n", name,
1527
host_name, ip, (intmax_t)interface, port);
1006
int ret = start_mandos_communication(ip, port, interface,
1007
avahi_proto_to_af(proto));
1529
int ret = start_mandos_communication(ip, (in_port_t)port,
1531
avahi_proto_to_af(proto),
1009
avahi_simple_poll_quit(mc.simple_poll);
1534
avahi_simple_poll_quit(simple_poll);
1011
ret = add_server(ip, port, interface,
1012
avahi_proto_to_af(proto));
1536
if(not add_server(ip, (in_port_t)port, interface,
1537
avahi_proto_to_af(proto),
1538
&((mandos_context*)mc)->current_server)){
1539
fprintf_plus(stderr, "Failed to add server \"%s\" to server"
1078
1614
signal_received = sig;
1079
1615
int old_errno = errno;
1080
1616
/* set main loop to exit */
1081
if(mc.simple_poll != NULL){
1082
avahi_simple_poll_quit(mc.simple_poll);
1617
if(simple_poll != NULL){
1618
avahi_simple_poll_quit(simple_poll);
1084
1620
errno = old_errno;
1623
__attribute__((nonnull, warn_unused_result))
1624
bool get_flags(const char *ifname, struct ifreq *ifr){
1628
int s = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1631
perror_plus("socket");
1635
strncpy(ifr->ifr_name, ifname, IF_NAMESIZE);
1636
ifr->ifr_name[IF_NAMESIZE-1] = '\0'; /* NUL terminate */
1637
ret = ioctl(s, SIOCGIFFLAGS, ifr);
1641
perror_plus("ioctl SIOCGIFFLAGS");
1649
__attribute__((nonnull, warn_unused_result))
1650
bool good_flags(const char *ifname, const struct ifreq *ifr){
1652
/* Reject the loopback device */
1653
if(ifr->ifr_flags & IFF_LOOPBACK){
1655
fprintf_plus(stderr, "Rejecting loopback interface \"%s\"\n",
1660
/* Accept point-to-point devices only if connect_to is specified */
1661
if(connect_to != NULL and (ifr->ifr_flags & IFF_POINTOPOINT)){
1663
fprintf_plus(stderr, "Accepting point-to-point interface"
1664
" \"%s\"\n", ifname);
1668
/* Otherwise, reject non-broadcast-capable devices */
1669
if(not (ifr->ifr_flags & IFF_BROADCAST)){
1671
fprintf_plus(stderr, "Rejecting non-broadcast interface"
1672
" \"%s\"\n", ifname);
1676
/* Reject non-ARP interfaces (including dummy interfaces) */
1677
if(ifr->ifr_flags & IFF_NOARP){
1679
fprintf_plus(stderr, "Rejecting non-ARP interface \"%s\"\n",
1685
/* Accept this device */
1687
fprintf_plus(stderr, "Interface \"%s\" is good\n", ifname);
1088
1693
* This function determines if a directory entry in /sys/class/net
1089
1694
* corresponds to an acceptable network device.
1090
1695
* (This function is passed to scandir(3) as a filter function.)
1697
__attribute__((nonnull, warn_unused_result))
1092
1698
int good_interface(const struct dirent *if_entry){
1094
char *flagname = NULL;
1095
1699
if(if_entry->d_name[0] == '.'){
1098
int ret = asprintf(&flagname, "%s/%s/flags", sys_class_net,
1101
perror_plus("asprintf");
1104
int flags_fd = (int)TEMP_FAILURE_RETRY(open(flagname, O_RDONLY));
1106
perror_plus("open");
1111
typedef short ifreq_flags; /* ifreq.ifr_flags in netdevice(7) */
1112
/* read line from flags_fd */
1113
ssize_t to_read = 2+(sizeof(ifreq_flags)*2)+1; /* "0x1003\n" */
1114
char *flagstring = malloc((size_t)to_read+1); /* +1 for final \0 */
1115
flagstring[(size_t)to_read] = '\0';
1116
if(flagstring == NULL){
1117
perror_plus("malloc");
1122
ssret = (ssize_t)TEMP_FAILURE_RETRY(read(flags_fd, flagstring,
1125
perror_plus("read");
1139
tmpmax = strtoimax(flagstring, &tmp, 0);
1140
if(errno != 0 or tmp == flagstring or (*tmp != '\0'
1141
and not (isspace(*tmp)))
1142
or tmpmax != (ifreq_flags)tmpmax){
1144
fprintf(stderr, "Invalid flags \"%s\" for interface \"%s\"\n",
1145
flagstring, if_entry->d_name);
1151
ifreq_flags flags = (ifreq_flags)tmpmax;
1152
/* Reject the loopback device */
1153
if(flags & IFF_LOOPBACK){
1155
fprintf(stderr, "Rejecting loopback interface \"%s\"\n",
1160
/* Accept point-to-point devices only if connect_to is specified */
1161
if(connect_to != NULL and (flags & IFF_POINTOPOINT)){
1163
fprintf(stderr, "Accepting point-to-point interface \"%s\"\n",
1168
/* Otherwise, reject non-broadcast-capable devices */
1169
if(not (flags & IFF_BROADCAST)){
1171
fprintf(stderr, "Rejecting non-broadcast interface \"%s\"\n",
1176
/* Reject non-ARP interfaces (including dummy interfaces) */
1177
if(flags & IFF_NOARP){
1179
fprintf(stderr, "Rejecting non-ARP interface \"%s\"\n",
1184
/* Accept this device */
1186
fprintf(stderr, "Interface \"%s\" is acceptable\n",
1704
if(not get_flags(if_entry->d_name, &ifr)){
1706
fprintf_plus(stderr, "Failed to get flags for interface "
1707
"\"%s\"\n", if_entry->d_name);
1712
if(not good_flags(if_entry->d_name, &ifr)){
1719
* This function determines if a network interface is up.
1721
__attribute__((nonnull, warn_unused_result))
1722
bool interface_is_up(const char *interface){
1724
if(not get_flags(interface, &ifr)){
1726
fprintf_plus(stderr, "Failed to get flags for interface "
1727
"\"%s\"\n", interface);
1732
return (bool)(ifr.ifr_flags & IFF_UP);
1736
* This function determines if a network interface is running
1738
__attribute__((nonnull, warn_unused_result))
1739
bool interface_is_running(const char *interface){
1741
if(not get_flags(interface, &ifr)){
1743
fprintf_plus(stderr, "Failed to get flags for interface "
1744
"\"%s\"\n", interface);
1749
return (bool)(ifr.ifr_flags & IFF_RUNNING);
1752
__attribute__((nonnull, pure, warn_unused_result))
1192
1753
int notdotentries(const struct dirent *direntry){
1193
1754
/* Skip "." and ".." */
1194
1755
if(direntry->d_name[0] == '.'
1203
int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval){
1764
/* Is this directory entry a runnable program? */
1765
__attribute__((nonnull, warn_unused_result))
1766
int runnable_hook(const struct dirent *direntry){
1771
if((direntry->d_name)[0] == '\0'){
1776
sret = strspn(direntry->d_name, "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
1777
"abcdefghijklmnopqrstuvwxyz"
1780
if((direntry->d_name)[sret] != '\0'){
1781
/* Contains non-allowed characters */
1783
fprintf_plus(stderr, "Ignoring hook \"%s\" with bad name\n",
1789
ret = fstatat(hookdir_fd, direntry->d_name, &st, 0);
1792
perror_plus("Could not stat hook");
1796
if(not (S_ISREG(st.st_mode))){
1797
/* Not a regular file */
1799
fprintf_plus(stderr, "Ignoring hook \"%s\" - not a file\n",
1804
if(not (st.st_mode & (S_IXUSR | S_IXGRP | S_IXOTH))){
1805
/* Not executable */
1807
fprintf_plus(stderr, "Ignoring hook \"%s\" - not executable\n",
1813
fprintf_plus(stderr, "Hook \"%s\" is acceptable\n",
1819
__attribute__((nonnull, warn_unused_result))
1820
int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,
1821
mandos_context *mc){
1205
1823
struct timespec now;
1206
1824
struct timespec waited_time;
1207
1825
intmax_t block_time;
1210
if(mc.current_server == NULL){
1213
"Wait until first server is found. No timeout!\n");
1828
if(mc->current_server == NULL){
1830
fprintf_plus(stderr, "Wait until first server is found."
1215
1833
ret = avahi_simple_poll_iterate(s, -1);
1218
fprintf(stderr, "Check current_server if we should run it,"
1836
fprintf_plus(stderr, "Check current_server if we should run"
1221
1839
/* the current time */
1222
1840
ret = clock_gettime(CLOCK_MONOTONIC, &now);
1227
1845
/* Calculating in ms how long time between now and server
1228
1846
who we visted longest time ago. Now - last seen. */
1229
1847
waited_time.tv_sec = (now.tv_sec
1230
- mc.current_server->last_seen.tv_sec);
1848
- mc->current_server->last_seen.tv_sec);
1231
1849
waited_time.tv_nsec = (now.tv_nsec
1232
- mc.current_server->last_seen.tv_nsec);
1850
- mc->current_server->last_seen.tv_nsec);
1233
1851
/* total time is 10s/10,000ms.
1234
1852
Converting to s from ms by dividing by 1,000,
1235
1853
and ns to ms by dividing by 1,000,000. */
1236
1854
block_time = ((retry_interval
1237
1855
- ((intmax_t)waited_time.tv_sec * 1000))
1238
1856
- ((intmax_t)waited_time.tv_nsec / 1000000));
1241
fprintf(stderr, "Blocking for %ld ms\n", block_time);
1859
fprintf_plus(stderr, "Blocking for %" PRIdMAX " ms\n",
1244
1863
if(block_time <= 0){
1245
ret = start_mandos_communication(mc.current_server->ip,
1246
mc.current_server->port,
1247
mc.current_server->if_index,
1248
mc.current_server->af);
1864
ret = start_mandos_communication(mc->current_server->ip,
1865
mc->current_server->port,
1866
mc->current_server->if_index,
1867
mc->current_server->af, mc);
1250
avahi_simple_poll_quit(mc.simple_poll);
1869
avahi_simple_poll_quit(s);
1253
1872
ret = clock_gettime(CLOCK_MONOTONIC,
1254
&mc.current_server->last_seen);
1873
&mc->current_server->last_seen);
1256
1875
perror_plus("clock_gettime");
1259
mc.current_server = mc.current_server->next;
1878
mc->current_server = mc->current_server->next;
1260
1879
block_time = 0; /* Call avahi to find new Mandos
1261
1880
servers, but don't block */
1264
1883
ret = avahi_simple_poll_iterate(s, (int)block_time);
1267
if (ret > 0 or errno != EINTR) {
1886
if(ret > 0 or errno != EINTR){
1268
1887
return (ret != 1) ? ret : 0;
1893
__attribute__((nonnull))
1894
void run_network_hooks(const char *mode, const char *interface,
1896
struct dirent **direntries = NULL;
1897
if(hookdir_fd == -1){
1898
hookdir_fd = open(hookdir, O_RDONLY | O_DIRECTORY | O_PATH
1900
if(hookdir_fd == -1){
1901
if(errno == ENOENT){
1903
fprintf_plus(stderr, "Network hook directory \"%s\" not"
1904
" found\n", hookdir);
1907
perror_plus("open");
1912
int numhooks = scandirat(hookdir_fd, ".", &direntries,
1913
runnable_hook, alphasort);
1915
perror_plus("scandir");
1918
struct dirent *direntry;
1920
int devnull = (int)TEMP_FAILURE_RETRY(open("/dev/null", O_RDONLY));
1922
perror_plus("open(\"/dev/null\", O_RDONLY)");
1925
for(int i = 0; i < numhooks; i++){
1926
direntry = direntries[i];
1928
fprintf_plus(stderr, "Running network hook \"%s\"\n",
1931
pid_t hook_pid = fork();
1934
/* Raise privileges */
1935
errno = raise_privileges_permanently();
1937
perror_plus("Failed to raise privileges");
1944
perror_plus("setgid");
1947
/* Reset supplementary groups */
1949
ret = setgroups(0, NULL);
1951
perror_plus("setgroups");
1954
ret = setenv("MANDOSNETHOOKDIR", hookdir, 1);
1956
perror_plus("setenv");
1959
ret = setenv("DEVICE", interface, 1);
1961
perror_plus("setenv");
1964
ret = setenv("VERBOSITY", debug ? "1" : "0", 1);
1966
perror_plus("setenv");
1969
ret = setenv("MODE", mode, 1);
1971
perror_plus("setenv");
1975
ret = asprintf(&delaystring, "%f", (double)delay);
1977
perror_plus("asprintf");
1980
ret = setenv("DELAY", delaystring, 1);
1983
perror_plus("setenv");
1987
if(connect_to != NULL){
1988
ret = setenv("CONNECT", connect_to, 1);
1990
perror_plus("setenv");
1994
int hook_fd = (int)TEMP_FAILURE_RETRY(openat(hookdir_fd,
1998
perror_plus("openat");
1999
_exit(EXIT_FAILURE);
2001
if(close(hookdir_fd) == -1){
2002
perror_plus("close");
2003
_exit(EXIT_FAILURE);
2005
ret = dup2(devnull, STDIN_FILENO);
2007
perror_plus("dup2(devnull, STDIN_FILENO)");
2010
ret = close(devnull);
2012
perror_plus("close");
2015
ret = dup2(STDERR_FILENO, STDOUT_FILENO);
2017
perror_plus("dup2(STDERR_FILENO, STDOUT_FILENO)");
2020
if(fexecve(hook_fd, (char *const []){ direntry->d_name, NULL },
2022
perror_plus("fexecve");
2023
_exit(EXIT_FAILURE);
2027
perror_plus("fork");
2032
if(TEMP_FAILURE_RETRY(waitpid(hook_pid, &status, 0)) == -1){
2033
perror_plus("waitpid");
2037
if(WIFEXITED(status)){
2038
if(WEXITSTATUS(status) != 0){
2039
fprintf_plus(stderr, "Warning: network hook \"%s\" exited"
2040
" with status %d\n", direntry->d_name,
2041
WEXITSTATUS(status));
2045
} else if(WIFSIGNALED(status)){
2046
fprintf_plus(stderr, "Warning: network hook \"%s\" died by"
2047
" signal %d\n", direntry->d_name,
2052
fprintf_plus(stderr, "Warning: network hook \"%s\""
2053
" crashed\n", direntry->d_name);
2059
fprintf_plus(stderr, "Network hook \"%s\" ran successfully\n",
2065
if(close(hookdir_fd) == -1){
2066
perror_plus("close");
2073
__attribute__((nonnull, warn_unused_result))
2074
error_t bring_up_interface(const char *const interface,
2076
error_t old_errno = errno;
2078
struct ifreq network;
2079
unsigned int if_index = if_nametoindex(interface);
2081
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
2091
if(not interface_is_up(interface)){
2092
error_t ret_errno = 0, ioctl_errno = 0;
2093
if(not get_flags(interface, &network)){
2095
fprintf_plus(stderr, "Failed to get flags for interface "
2096
"\"%s\"\n", interface);
2100
network.ifr_flags |= IFF_UP; /* set flag */
2102
int sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
2105
perror_plus("socket");
2113
perror_plus("close");
2120
fprintf_plus(stderr, "Bringing up interface \"%s\"\n",
2124
/* Raise privileges */
2125
ret_errno = raise_privileges();
2128
perror_plus("Failed to raise privileges");
2133
bool restore_loglevel = false;
2135
/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO
2136
messages about the network interface to mess up the prompt */
2137
ret_linux = klogctl(8, NULL, 5);
2138
if(ret_linux == -1){
2139
perror_plus("klogctl");
2141
restore_loglevel = true;
2144
#endif /* __linux__ */
2145
int ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
2146
ioctl_errno = errno;
2148
if(restore_loglevel){
2149
ret_linux = klogctl(7, NULL, 0);
2150
if(ret_linux == -1){
2151
perror_plus("klogctl");
2154
#endif /* __linux__ */
2156
/* If raise_privileges() succeeded above */
2158
/* Lower privileges */
2159
ret_errno = lower_privileges();
2162
perror_plus("Failed to lower privileges");
2166
/* Close the socket */
2169
perror_plus("close");
2172
if(ret_setflags == -1){
2173
errno = ioctl_errno;
2174
perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");
2179
fprintf_plus(stderr, "Interface \"%s\" is already up; good\n",
2183
/* Sleep checking until interface is running.
2184
Check every 0.25s, up to total time of delay */
2185
for(int i=0; i < delay * 4; i++){
2186
if(interface_is_running(interface)){
2189
struct timespec sleeptime = { .tv_nsec = 250000000 };
2190
ret = nanosleep(&sleeptime, NULL);
2191
if(ret == -1 and errno != EINTR){
2192
perror_plus("nanosleep");
2200
__attribute__((nonnull, warn_unused_result))
2201
error_t take_down_interface(const char *const interface){
2202
error_t old_errno = errno;
2203
struct ifreq network;
2204
unsigned int if_index = if_nametoindex(interface);
2206
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
2210
if(interface_is_up(interface)){
2211
error_t ret_errno = 0, ioctl_errno = 0;
2212
if(not get_flags(interface, &network) and debug){
2214
fprintf_plus(stderr, "Failed to get flags for interface "
2215
"\"%s\"\n", interface);
2219
network.ifr_flags &= ~(short)IFF_UP; /* clear flag */
2221
int sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
2224
perror_plus("socket");
2230
fprintf_plus(stderr, "Taking down interface \"%s\"\n",
2234
/* Raise privileges */
2235
ret_errno = raise_privileges();
2238
perror_plus("Failed to raise privileges");
2241
int ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
2242
ioctl_errno = errno;
2244
/* If raise_privileges() succeeded above */
2246
/* Lower privileges */
2247
ret_errno = lower_privileges();
2250
perror_plus("Failed to lower privileges");
2254
/* Close the socket */
2255
int ret = close(sd);
2257
perror_plus("close");
2260
if(ret_setflags == -1){
2261
errno = ioctl_errno;
2262
perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");
2267
fprintf_plus(stderr, "Interface \"%s\" is already down; odd\n",
1274
2275
int main(int argc, char *argv[]){
2276
mandos_context mc = { .server = NULL, .dh_bits = 0,
2277
.priority = "SECURE256:!CTYPE-X.509"
2278
":+CTYPE-OPENPGP:!RSA:+SIGN-DSA-SHA256",
2279
.current_server = NULL, .interfaces = NULL,
2280
.interfaces_size = 0 };
1275
2281
AvahiSServiceBrowser *sb = NULL;
1278
2284
intmax_t tmpmax;
1280
2286
int exitcode = EXIT_SUCCESS;
1281
const char *interface = "";
1282
struct ifreq network;
1284
bool take_down_interface = false;
1287
char tempdir[] = "/tmp/mandosXXXXXX";
1288
bool tempdir_created = false;
2287
char *interfaces_to_take_down = NULL;
2288
size_t interfaces_to_take_down_size = 0;
2289
char run_tempdir[] = "/run/tmp/mandosXXXXXX";
2290
char old_tempdir[] = "/tmp/mandosXXXXXX";
2291
char *tempdir = NULL;
1289
2292
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
1290
2293
const char *seckey = PATHDIR "/" SECKEY;
1291
2294
const char *pubkey = PATHDIR "/" PUBKEY;
2295
const char *dh_params_file = NULL;
2296
char *interfaces_hooks = NULL;
1293
2298
bool gnutls_initialized = false;
1294
2299
bool gpgme_initialized = false;
1460
2485
/* Work around Debian bug #633582:
1461
2486
<http://bugs.debian.org/633582> */
1464
/* Re-raise priviliges */
1468
perror_plus("seteuid");
1471
int seckey_fd = open(PATHDIR "/" SECKEY, O_RDONLY);
1472
if(seckey_fd == -1){
1473
perror_plus("open");
1475
ret = (int)TEMP_FAILURE_RETRY(fstat(seckey_fd, &st));
1477
perror_plus("fstat");
1479
if(S_ISREG(st.st_mode) and st.st_uid == 0 and st.st_gid == 0){
1480
ret = fchown(seckey_fd, uid, gid);
1482
perror_plus("fchown");
1486
TEMP_FAILURE_RETRY(close(seckey_fd));
1489
int pubkey_fd = open(PATHDIR "/" PUBKEY, O_RDONLY);
1490
if(pubkey_fd == -1){
1491
perror_plus("open");
1493
ret = (int)TEMP_FAILURE_RETRY(fstat(pubkey_fd, &st));
1495
perror_plus("fstat");
1497
if(S_ISREG(st.st_mode) and st.st_uid == 0 and st.st_gid == 0){
1498
ret = fchown(pubkey_fd, uid, gid);
1500
perror_plus("fchown");
1504
TEMP_FAILURE_RETRY(close(pubkey_fd));
1507
/* Lower privileges */
1511
perror_plus("seteuid");
2488
/* Re-raise privileges */
2489
ret_errno = raise_privileges();
2492
perror_plus("Failed to raise privileges");
2496
if(strcmp(seckey, PATHDIR "/" SECKEY) == 0){
2497
int seckey_fd = open(seckey, O_RDONLY);
2498
if(seckey_fd == -1){
2499
perror_plus("open");
2501
ret = (int)TEMP_FAILURE_RETRY(fstat(seckey_fd, &st));
2503
perror_plus("fstat");
2505
if(S_ISREG(st.st_mode)
2506
and st.st_uid == 0 and st.st_gid == 0){
2507
ret = fchown(seckey_fd, uid, gid);
2509
perror_plus("fchown");
2517
if(strcmp(pubkey, PATHDIR "/" PUBKEY) == 0){
2518
int pubkey_fd = open(pubkey, O_RDONLY);
2519
if(pubkey_fd == -1){
2520
perror_plus("open");
2522
ret = (int)TEMP_FAILURE_RETRY(fstat(pubkey_fd, &st));
2524
perror_plus("fstat");
2526
if(S_ISREG(st.st_mode)
2527
and st.st_uid == 0 and st.st_gid == 0){
2528
ret = fchown(pubkey_fd, uid, gid);
2530
perror_plus("fchown");
2538
if(dh_params_file != NULL
2539
and strcmp(dh_params_file, PATHDIR "/dhparams.pem" ) == 0){
2540
int dhparams_fd = open(dh_params_file, O_RDONLY);
2541
if(dhparams_fd == -1){
2542
perror_plus("open");
2544
ret = (int)TEMP_FAILURE_RETRY(fstat(dhparams_fd, &st));
2546
perror_plus("fstat");
2548
if(S_ISREG(st.st_mode)
2549
and st.st_uid == 0 and st.st_gid == 0){
2550
ret = fchown(dhparams_fd, uid, gid);
2552
perror_plus("fchown");
2560
/* Lower privileges */
2561
ret_errno = lower_privileges();
2564
perror_plus("Failed to lower privileges");
2569
/* Remove invalid interface names (except "none") */
2571
char *interface = NULL;
2572
while((interface = argz_next(mc.interfaces, mc.interfaces_size,
2574
if(strcmp(interface, "none") != 0
2575
and if_nametoindex(interface) == 0){
2576
if(interface[0] != '\0'){
2577
fprintf_plus(stderr, "Not using nonexisting interface"
2578
" \"%s\"\n", interface);
2580
argz_delete(&mc.interfaces, &mc.interfaces_size, interface);
2586
/* Run network hooks */
2588
if(mc.interfaces != NULL){
2589
interfaces_hooks = malloc(mc.interfaces_size);
2590
if(interfaces_hooks == NULL){
2591
perror_plus("malloc");
2594
memcpy(interfaces_hooks, mc.interfaces, mc.interfaces_size);
2595
argz_stringify(interfaces_hooks, mc.interfaces_size, (int)',');
2597
run_network_hooks("start", interfaces_hooks != NULL ?
2598
interfaces_hooks : "", delay);
1516
2602
avahi_set_log_function(empty_log);
1519
if(interface[0] == '\0'){
1520
struct dirent **direntries;
1521
ret = scandir(sys_class_net, &direntries, good_interface,
1524
/* Pick the first good interface */
1525
interface = strdup(direntries[0]->d_name);
1527
fprintf(stderr, "Using interface \"%s\"\n", interface);
1529
if(interface == NULL){
1530
perror_plus("malloc");
1532
exitcode = EXIT_FAILURE;
1538
fprintf(stderr, "Could not find a network interface\n");
1539
exitcode = EXIT_FAILURE;
1544
2605
/* Initialize Avahi early so avahi_simple_poll_quit() can be called
1545
2606
from the signal handler */
1546
2607
/* Initialize the pseudo-RNG for Avahi */
1547
2608
srand((unsigned int) time(NULL));
1548
mc.simple_poll = avahi_simple_poll_new();
1549
if(mc.simple_poll == NULL){
1550
fprintf(stderr, "Avahi: Failed to create simple poll object.\n");
2609
simple_poll = avahi_simple_poll_new();
2610
if(simple_poll == NULL){
2611
fprintf_plus(stderr,
2612
"Avahi: Failed to create simple poll object.\n");
1551
2613
exitcode = EX_UNAVAILABLE;
1618
/* If the interface is down, bring it up */
1619
if(strcmp(interface, "none") != 0){
1620
if_index = (AvahiIfIndex) if_nametoindex(interface);
1622
fprintf(stderr, "No such interface: \"%s\"\n", interface);
1623
exitcode = EX_UNAVAILABLE;
1631
/* Re-raise priviliges */
1635
perror_plus("seteuid");
1639
/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO
1640
messages about the network interface to mess up the prompt */
1641
ret = klogctl(8, NULL, 5);
1642
bool restore_loglevel = true;
1644
restore_loglevel = false;
1645
perror_plus("klogctl");
1647
#endif /* __linux__ */
1649
sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1651
perror_plus("socket");
1652
exitcode = EX_OSERR;
1654
if(restore_loglevel){
1655
ret = klogctl(7, NULL, 0);
1657
perror_plus("klogctl");
1660
#endif /* __linux__ */
1661
/* Lower privileges */
1665
perror_plus("seteuid");
1669
strcpy(network.ifr_name, interface);
1670
ret = ioctl(sd, SIOCGIFFLAGS, &network);
1672
perror_plus("ioctl SIOCGIFFLAGS");
1674
if(restore_loglevel){
1675
ret = klogctl(7, NULL, 0);
1677
perror_plus("klogctl");
1680
#endif /* __linux__ */
1681
exitcode = EX_OSERR;
1682
/* Lower privileges */
1686
perror_plus("seteuid");
1690
if((network.ifr_flags & IFF_UP) == 0){
1691
network.ifr_flags |= IFF_UP;
1692
take_down_interface = true;
1693
ret = ioctl(sd, SIOCSIFFLAGS, &network);
1695
take_down_interface = false;
1696
perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");
1697
exitcode = EX_OSERR;
1699
if(restore_loglevel){
1700
ret = klogctl(7, NULL, 0);
1702
perror_plus("klogctl");
2680
/* If no interfaces were specified, make a list */
2681
if(mc.interfaces == NULL){
2682
struct dirent **direntries = NULL;
2683
/* Look for any good interfaces */
2684
ret = scandir(sys_class_net, &direntries, good_interface,
2687
/* Add all found interfaces to interfaces list */
2688
for(int i = 0; i < ret; ++i){
2689
ret_errno = argz_add(&mc.interfaces, &mc.interfaces_size,
2690
direntries[i]->d_name);
2693
perror_plus("argz_add");
2694
free(direntries[i]);
2698
fprintf_plus(stderr, "Will use interface \"%s\"\n",
2699
direntries[i]->d_name);
2701
free(direntries[i]);
2708
fprintf_plus(stderr, "Could not find a network interface\n");
2709
exitcode = EXIT_FAILURE;
2714
/* Bring up interfaces which are down, and remove any "none"s */
2716
char *interface = NULL;
2717
while((interface = argz_next(mc.interfaces, mc.interfaces_size,
2719
/* If interface name is "none", stop bringing up interfaces.
2720
Also remove all instances of "none" from the list */
2721
if(strcmp(interface, "none") == 0){
2722
argz_delete(&mc.interfaces, &mc.interfaces_size,
2725
while((interface = argz_next(mc.interfaces,
2726
mc.interfaces_size, interface))){
2727
if(strcmp(interface, "none") == 0){
2728
argz_delete(&mc.interfaces, &mc.interfaces_size,
1705
#endif /* __linux__ */
1706
/* Lower privileges */
1710
perror_plus("seteuid");
1715
/* Sleep checking until interface is running.
1716
Check every 0.25s, up to total time of delay */
1717
for(int i=0; i < delay * 4; i++){
1718
ret = ioctl(sd, SIOCGIFFLAGS, &network);
1720
perror_plus("ioctl SIOCGIFFLAGS");
1721
} else if(network.ifr_flags & IFF_RUNNING){
1724
struct timespec sleeptime = { .tv_nsec = 250000000 };
1725
ret = nanosleep(&sleeptime, NULL);
1726
if(ret == -1 and errno != EINTR){
1727
perror_plus("nanosleep");
1730
if(not take_down_interface){
1731
/* We won't need the socket anymore */
1732
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1734
perror_plus("close");
1738
if(restore_loglevel){
1739
/* Restores kernel loglevel to default */
1740
ret = klogctl(7, NULL, 0);
1742
perror_plus("klogctl");
1745
#endif /* __linux__ */
1746
/* Lower privileges */
1748
if(take_down_interface){
1749
/* Lower privileges */
1752
perror_plus("seteuid");
1755
/* Lower privileges permanently */
1758
perror_plus("setuid");
2735
bool interface_was_up = interface_is_up(interface);
2736
errno = bring_up_interface(interface, delay);
2737
if(not interface_was_up){
2739
fprintf_plus(stderr, "Failed to bring up interface \"%s\":"
2740
" %s\n", interface, strerror(errno));
2742
errno = argz_add(&interfaces_to_take_down,
2743
&interfaces_to_take_down_size,
2746
perror_plus("argz_add");
2751
if(debug and (interfaces_to_take_down == NULL)){
2752
fprintf_plus(stderr, "No interfaces were brought up\n");
2756
/* If we only got one interface, explicitly use only that one */
2757
if(argz_count(mc.interfaces, mc.interfaces_size) == 1){
2759
fprintf_plus(stderr, "Using only interface \"%s\"\n",
2762
if_index = (AvahiIfIndex)if_nametoindex(mc.interfaces);
1767
ret = init_gnutls_global(pubkey, seckey);
2769
ret = init_gnutls_global(pubkey, seckey, dh_params_file, &mc);
1769
fprintf(stderr, "init_gnutls_global failed\n");
2771
fprintf_plus(stderr, "init_gnutls_global failed\n");
1770
2772
exitcode = EX_UNAVAILABLE;
1909
2931
/* Run the main loop */
1912
fprintf(stderr, "Starting Avahi loop search\n");
2934
fprintf_plus(stderr, "Starting Avahi loop search\n");
1915
ret = avahi_loop_with_timeout(mc.simple_poll,
1916
(int)(retry_interval * 1000));
2937
ret = avahi_loop_with_timeout(simple_poll,
2938
(int)(retry_interval * 1000), &mc);
1918
fprintf(stderr, "avahi_loop_with_timeout exited %s\n",
1919
(ret == 0) ? "successfully" : "with error");
2940
fprintf_plus(stderr, "avahi_loop_with_timeout exited %s\n",
2941
(ret == 0) ? "successfully" : "with error");
1925
fprintf(stderr, "%s exiting\n", argv[0]);
2947
fprintf_plus(stderr, "%s exiting\n", argv[0]);
1928
2950
/* Cleanup things */
2951
free(mc.interfaces);
1930
2954
avahi_s_service_browser_free(sb);
1932
2956
if(mc.server != NULL)
1933
2957
avahi_server_free(mc.server);
1935
if(mc.simple_poll != NULL)
1936
avahi_simple_poll_free(mc.simple_poll);
2959
if(simple_poll != NULL)
2960
avahi_simple_poll_free(simple_poll);
1938
2962
if(gnutls_initialized){
1939
2963
gnutls_certificate_free_credentials(mc.cred);
1940
gnutls_global_deinit();
1941
2964
gnutls_dh_params_deinit(mc.dh_params);
1944
2967
if(gpgme_initialized){
1945
2968
gpgme_release(mc.ctx);
1948
2971
/* Cleans up the circular linked list of Mandos servers the client
1950
2973
if(mc.current_server != NULL){
1951
2974
mc.current_server->prev->next = NULL;
1952
2975
while(mc.current_server != NULL){
1953
2976
server *next = mc.current_server->next;
2978
#pragma GCC diagnostic push
2979
#pragma GCC diagnostic ignored "-Wcast-qual"
2981
free((char *)(mc.current_server->ip));
2983
#pragma GCC diagnostic pop
1954
2985
free(mc.current_server);
1955
2986
mc.current_server = next;
1959
/* Take down the network interface */
1960
if(take_down_interface){
1961
/* Re-raise priviliges */
1965
perror_plus("seteuid");
1968
ret = ioctl(sd, SIOCGIFFLAGS, &network);
1970
perror_plus("ioctl SIOCGIFFLAGS");
1971
} else if(network.ifr_flags & IFF_UP) {
1972
network.ifr_flags &= ~(short)IFF_UP; /* clear flag */
1973
ret = ioctl(sd, SIOCSIFFLAGS, &network);
1975
perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");
1978
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1980
perror_plus("close");
1982
/* Lower privileges permanently */
1986
perror_plus("setuid");
2990
/* Re-raise privileges */
2992
ret_errno = raise_privileges();
2995
perror_plus("Failed to raise privileges");
2998
/* Run network hooks */
2999
run_network_hooks("stop", interfaces_hooks != NULL ?
3000
interfaces_hooks : "", delay);
3002
/* Take down the network interfaces which were brought up */
3004
char *interface = NULL;
3005
while((interface=argz_next(interfaces_to_take_down,
3006
interfaces_to_take_down_size,
3008
ret_errno = take_down_interface(interface);
3011
perror_plus("Failed to take down interface");
3014
if(debug and (interfaces_to_take_down == NULL)){
3015
fprintf_plus(stderr, "No interfaces needed to be taken"
3021
ret_errno = lower_privileges_permanently();
3024
perror_plus("Failed to lower privileges permanently");
3028
free(interfaces_to_take_down);
3029
free(interfaces_hooks);
3031
void clean_dir_at(int base, const char * const dirname,
3033
struct dirent **direntries = NULL;
3035
int dir_fd = (int)TEMP_FAILURE_RETRY(openat(base, dirname,
3041
perror_plus("open");
3043
int numentries = scandirat(dir_fd, ".", &direntries,
3044
notdotentries, alphasort);
3045
if(numentries >= 0){
3046
for(int i = 0; i < numentries; i++){
3048
fprintf_plus(stderr, "Unlinking \"%s/%s\"\n",
3049
dirname, direntries[i]->d_name);
3051
dret = unlinkat(dir_fd, direntries[i]->d_name, 0);
3053
if(errno == EISDIR){
3054
dret = unlinkat(dir_fd, direntries[i]->d_name,
3057
if((dret == -1) and (errno == ENOTEMPTY)
3058
and (strcmp(direntries[i]->d_name, "private-keys-v1.d")
3059
== 0) and (level == 0)){
3060
/* Recurse only in this special case */
3061
clean_dir_at(dir_fd, direntries[i]->d_name, level+1);
3065
fprintf_plus(stderr, "unlink(\"%s/%s\"): %s\n", dirname,
3066
direntries[i]->d_name, strerror(errno));
3069
free(direntries[i]);
3072
/* need to clean even if 0 because man page doesn't specify */
3074
if(numentries == -1){
3075
perror_plus("scandirat");
3077
dret = unlinkat(base, dirname, AT_REMOVEDIR);
3078
if(dret == -1 and errno != ENOENT){
3079
perror_plus("rmdir");
3082
perror_plus("scandirat");
1991
3087
/* Removes the GPGME temp directory and all files inside */
1992
if(tempdir_created){
1993
struct dirent **direntries = NULL;
1994
struct dirent *direntry = NULL;
1995
ret = scandir(tempdir, &direntries, notdotentries, alphasort);
1997
for(int i = 0; i < ret; i++){
1998
direntry = direntries[i];
1999
char *fullname = NULL;
2000
ret = asprintf(&fullname, "%s/%s", tempdir,
2003
perror_plus("asprintf");
2006
ret = remove(fullname);
2008
fprintf(stderr, "remove(\"%s\"): %s\n", fullname,
2015
/* need to be cleaned even if ret == 0 because man page doesn't
2019
perror_plus("scandir");
2021
ret = rmdir(tempdir);
2022
if(ret == -1 and errno != ENOENT){
2023
perror_plus("rmdir");
3088
if(tempdir != NULL){
3089
clean_dir_at(-1, tempdir, 0);