26
26
* along with this program. If not, see
27
27
* <http://www.gnu.org/licenses/>.
29
* Contact the authors at <mandos@recompile.se>.
29
* Contact the authors at <mandos@fukt.bsnet.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(),
44
#include <stdint.h> /* uint16_t, uint32_t, intptr_t */
43
stdout, ferror(), remove() */
44
#include <stdint.h> /* uint16_t, uint32_t */
45
45
#include <stddef.h> /* NULL, size_t, ssize_t */
46
#include <stdlib.h> /* free(), EXIT_SUCCESS, srand(),
46
#include <stdlib.h> /* free(), EXIT_SUCCESS, EXIT_FAILURE,
48
48
#include <stdbool.h> /* bool, false, true */
49
#include <string.h> /* strcmp(), strlen(), strerror(),
50
asprintf(), strncpy() */
49
#include <string.h> /* memset(), strcmp(), strlen(),
50
strerror(), asprintf(), strcpy() */
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(), S_ISREG */
56
#include <sys/stat.h> /* open() */
57
57
#include <sys/socket.h> /* socket(), struct sockaddr_in6,
58
inet_pton(), connect(),
60
#include <fcntl.h> /* open(), unlinkat(), AT_REMOVEDIR */
58
inet_pton(), connect() */
59
#include <fcntl.h> /* open() */
61
60
#include <dirent.h> /* opendir(), struct dirent, readdir()
63
62
#include <inttypes.h> /* PRIu16, PRIdMAX, intmax_t,
65
#include <errno.h> /* perror(), errno, EINTR, EINVAL,
66
EAI_SYSTEM, ENETUNREACH,
67
EHOSTUNREACH, ECONNREFUSED, EPROTO,
68
EIO, ENOENT, ENXIO, ENOMEM, EISDIR,
70
program_invocation_short_name */
71
#include <time.h> /* nanosleep(), time(), sleep() */
64
#include <assert.h> /* assert() */
65
#include <errno.h> /* perror(), errno */
66
#include <time.h> /* nanosleep(), time() */
72
67
#include <net/if.h> /* ioctl, ifreq, SIOCGIFFLAGS, IFF_UP,
73
68
SIOCSIFFLAGS, if_indextoname(),
74
69
if_nametoindex(), IF_NAMESIZE */
137
120
#define PATHDIR "/conf/conf.d/mandos"
138
121
#define SECKEY "seckey.txt"
139
122
#define PUBKEY "pubkey.txt"
140
#define HOOKDIR "/lib/mandos/network-hooks.d"
142
124
bool debug = false;
143
125
static const char mandos_protocol_version[] = "1";
144
126
const char *argp_program_version = "mandos-client " VERSION;
145
const char *argp_program_bug_address = "<mandos@recompile.se>";
146
static const char sys_class_net[] = "/sys/class/net";
147
char *connect_to = NULL;
148
const char *hookdir = HOOKDIR;
153
/* Doubly linked list that need to be circularly linked when used */
154
typedef struct server{
157
AvahiIfIndex if_index;
159
struct timespec last_seen;
127
const char *argp_program_bug_address = "<mandos@fukt.bsnet.se>";
164
129
/* Used for passing in values through the Avahi callback functions */
131
AvahiSimplePoll *simple_poll;
166
132
AvahiServer *server;
167
133
gnutls_certificate_credentials_t cred;
168
134
unsigned int dh_bits;
169
135
gnutls_dh_params_t dh_params;
170
136
const char *priority;
172
server *current_server;
174
size_t interfaces_size;
175
138
} mandos_context;
177
/* global so signal handler can reach it*/
178
AvahiSimplePoll *simple_poll;
180
sig_atomic_t quit_now = 0;
181
int signal_received = 0;
183
/* Function to use when printing errors */
184
void perror_plus(const char *print_text){
186
fprintf(stderr, "Mandos plugin %s: ",
187
program_invocation_short_name);
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));
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" };
203
146
* Make additional room in "buffer" for at least BUFFER_SIZE more
204
147
* bytes. "buffer_capacity" is how much is currently allocated,
205
148
* "buffer_length" is how much is already used.
207
__attribute__((nonnull, warn_unused_result))
208
150
size_t incbuffer(char **buffer, size_t buffer_length,
209
size_t buffer_capacity){
151
size_t buffer_capacity){
210
152
if(buffer_length + BUFFER_SIZE > buffer_capacity){
211
char *new_buf = realloc(*buffer, buffer_capacity + BUFFER_SIZE);
213
int old_errno = errno;
153
*buffer = realloc(*buffer, buffer_capacity + BUFFER_SIZE);
220
157
buffer_capacity += BUFFER_SIZE;
222
159
return buffer_capacity;
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){
230
server *new_server = malloc(sizeof(server));
231
if(new_server == NULL){
232
perror_plus("malloc");
235
*new_server = (server){ .ip = strdup(ip),
237
.if_index = if_index,
239
if(new_server->ip == NULL){
240
perror_plus("strdup");
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){
260
new_server->next = new_server;
261
new_server->prev = new_server;
262
*current_server = new_server;
264
/* Place the new server last in the list */
265
new_server->next = *current_server;
266
new_server->prev = (*current_server)->prev;
267
new_server->prev->next = new_server;
268
(*current_server)->prev = new_server;
274
163
* Initialize GPGME.
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,
165
static bool init_gpgme(const char *seckey,
166
const char *pubkey, const char *tempdir){
281
167
gpgme_error_t rc;
282
168
gpgme_engine_info_t engine_info;
285
172
* Helper function to insert pub and seckey to the engine keyring.
287
bool import_key(const char * const filename){
174
bool import_key(const char *filename){
290
177
gpgme_data_t pgp_data;
292
179
fd = (int)TEMP_FAILURE_RETRY(open(filename, O_RDONLY));
298
185
rc = gpgme_data_new_from_fd(&pgp_data, fd);
299
186
if(rc != GPG_ERR_NO_ERROR){
300
fprintf_plus(stderr, "bad gpgme_data_new_from_fd: %s: %s\n",
301
gpgme_strsource(rc), gpgme_strerror(rc));
187
fprintf(stderr, "bad gpgme_data_new_from_fd: %s: %s\n",
188
gpgme_strsource(rc), gpgme_strerror(rc));
305
rc = gpgme_op_import(mc->ctx, pgp_data);
192
rc = gpgme_op_import(mc.ctx, pgp_data);
306
193
if(rc != GPG_ERR_NO_ERROR){
307
fprintf_plus(stderr, "bad gpgme_op_import: %s: %s\n",
308
gpgme_strsource(rc), gpgme_strerror(rc));
194
fprintf(stderr, "bad gpgme_op_import: %s: %s\n",
195
gpgme_strsource(rc), gpgme_strerror(rc));
199
ret = (int)TEMP_FAILURE_RETRY(close(fd));
314
perror_plus("close");
316
203
gpgme_data_release(pgp_data);
321
fprintf_plus(stderr, "Initializing GPGME\n");
208
fprintf(stderr, "Initializing GPGME\n");
325
212
gpgme_check_version(NULL);
326
213
rc = gpgme_engine_check_version(GPGME_PROTOCOL_OpenPGP);
327
214
if(rc != GPG_ERR_NO_ERROR){
328
fprintf_plus(stderr, "bad gpgme_engine_check_version: %s: %s\n",
329
gpgme_strsource(rc), gpgme_strerror(rc));
215
fprintf(stderr, "bad gpgme_engine_check_version: %s: %s\n",
216
gpgme_strsource(rc), gpgme_strerror(rc));
333
/* Set GPGME home directory for the OpenPGP engine only */
220
/* Set GPGME home directory for the OpenPGP engine only */
334
221
rc = gpgme_get_engine_info(&engine_info);
335
222
if(rc != GPG_ERR_NO_ERROR){
336
fprintf_plus(stderr, "bad gpgme_get_engine_info: %s: %s\n",
337
gpgme_strsource(rc), gpgme_strerror(rc));
223
fprintf(stderr, "bad gpgme_get_engine_info: %s: %s\n",
224
gpgme_strsource(rc), gpgme_strerror(rc));
340
227
while(engine_info != NULL){
383
266
ssize_t plaintext_length = 0;
386
fprintf_plus(stderr, "Trying to decrypt OpenPGP data\n");
269
fprintf(stderr, "Trying to decrypt OpenPGP data\n");
389
272
/* Create new GPGME data buffer from memory cryptotext */
390
273
rc = gpgme_data_new_from_mem(&dh_crypto, cryptotext, crypto_size,
392
275
if(rc != GPG_ERR_NO_ERROR){
393
fprintf_plus(stderr, "bad gpgme_data_new_from_mem: %s: %s\n",
394
gpgme_strsource(rc), gpgme_strerror(rc));
276
fprintf(stderr, "bad gpgme_data_new_from_mem: %s: %s\n",
277
gpgme_strsource(rc), gpgme_strerror(rc));
398
281
/* Create new empty GPGME data buffer for the plaintext */
399
282
rc = gpgme_data_new(&dh_plain);
400
283
if(rc != GPG_ERR_NO_ERROR){
401
fprintf_plus(stderr, "Mandos plugin mandos-client: "
402
"bad gpgme_data_new: %s: %s\n",
403
gpgme_strsource(rc), gpgme_strerror(rc));
284
fprintf(stderr, "bad gpgme_data_new: %s: %s\n",
285
gpgme_strsource(rc), gpgme_strerror(rc));
404
286
gpgme_data_release(dh_crypto);
408
290
/* Decrypt data from the cryptotext data buffer to the plaintext
410
rc = gpgme_op_decrypt(mc->ctx, dh_crypto, dh_plain);
292
rc = gpgme_op_decrypt(mc.ctx, dh_crypto, dh_plain);
411
293
if(rc != GPG_ERR_NO_ERROR){
412
fprintf_plus(stderr, "bad gpgme_op_decrypt: %s: %s\n",
413
gpgme_strsource(rc), gpgme_strerror(rc));
294
fprintf(stderr, "bad gpgme_op_decrypt: %s: %s\n",
295
gpgme_strsource(rc), gpgme_strerror(rc));
414
296
plaintext_length = -1;
416
298
gpgme_decrypt_result_t result;
417
result = gpgme_op_decrypt_result(mc->ctx);
299
result = gpgme_op_decrypt_result(mc.ctx);
418
300
if(result == NULL){
419
fprintf_plus(stderr, "gpgme_op_decrypt_result failed\n");
301
fprintf(stderr, "gpgme_op_decrypt_result failed\n");
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);
303
fprintf(stderr, "Unsupported algorithm: %s\n",
304
result->unsupported_algorithm);
305
fprintf(stderr, "Wrong key usage: %u\n",
306
result->wrong_key_usage);
425
307
if(result->file_name != NULL){
426
fprintf_plus(stderr, "File name: %s\n", result->file_name);
308
fprintf(stderr, "File name: %s\n", result->file_name);
428
310
gpgme_recipient_t recipient;
429
311
recipient = result->recipients;
430
312
while(recipient != NULL){
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
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
438
319
recipient = recipient->next;
540
418
/* OpenPGP credentials */
541
ret = gnutls_certificate_allocate_credentials(&mc->cred);
419
gnutls_certificate_allocate_credentials(&mc.cred);
542
420
if(ret != GNUTLS_E_SUCCESS){
543
fprintf_plus(stderr, "GnuTLS memory error: %s\n",
544
safer_gnutls_strerror(ret));
421
fprintf(stderr, "GnuTLS memory error: %s\n", /* Spurious warning
425
safer_gnutls_strerror(ret));
426
gnutls_global_deinit();
549
fprintf_plus(stderr, "Attempting to use OpenPGP public key %s and"
550
" secret key %s as GnuTLS credentials\n",
431
fprintf(stderr, "Attempting to use OpenPGP public key %s and"
432
" secret key %s as GnuTLS credentials\n", pubkeyfilename,
555
436
ret = gnutls_certificate_set_openpgp_key_file
556
(mc->cred, pubkeyfilename, seckeyfilename,
437
(mc.cred, pubkeyfilename, seckeyfilename,
557
438
GNUTLS_OPENPGP_FMT_BASE64);
558
439
if(ret != GNUTLS_E_SUCCESS){
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));
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));
567
448
/* GnuTLS server initialization */
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);
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);
753
gnutls_certificate_free_credentials(mc->cred);
754
gnutls_dh_params_deinit(mc->dh_params);
468
gnutls_certificate_free_credentials(mc.cred);
469
gnutls_global_deinit();
470
gnutls_dh_params_deinit(mc.dh_params);
758
__attribute__((nonnull, warn_unused_result))
759
static int init_gnutls_session(gnutls_session_t *session,
474
static int init_gnutls_session(gnutls_session_t *session){
762
476
/* GnuTLS session creation */
764
ret = gnutls_init(session, GNUTLS_SERVER);
768
} while(ret == GNUTLS_E_INTERRUPTED or ret == GNUTLS_E_AGAIN);
477
ret = gnutls_init(session, GNUTLS_SERVER);
769
478
if(ret != GNUTLS_E_SUCCESS){
771
"Error in GnuTLS session initialization: %s\n",
772
safer_gnutls_strerror(ret));
479
fprintf(stderr, "Error in GnuTLS session initialization: %s\n",
480
safer_gnutls_strerror(ret));
778
ret = gnutls_priority_set_direct(*session, mc->priority, &err);
780
gnutls_deinit(*session);
783
} while(ret == GNUTLS_E_INTERRUPTED or ret == GNUTLS_E_AGAIN);
485
ret = gnutls_priority_set_direct(*session, mc.priority, &err);
784
486
if(ret != GNUTLS_E_SUCCESS){
785
fprintf_plus(stderr, "Syntax error at: %s\n", err);
786
fprintf_plus(stderr, "GnuTLS error: %s\n",
787
safer_gnutls_strerror(ret));
487
fprintf(stderr, "Syntax error at: %s\n", err);
488
fprintf(stderr, "GnuTLS error: %s\n",
489
safer_gnutls_strerror(ret));
788
490
gnutls_deinit(*session);
794
ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,
797
gnutls_deinit(*session);
800
} while(ret == GNUTLS_E_INTERRUPTED or ret == GNUTLS_E_AGAIN);
495
ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,
801
497
if(ret != GNUTLS_E_SUCCESS){
802
fprintf_plus(stderr, "Error setting GnuTLS credentials: %s\n",
803
safer_gnutls_strerror(ret));
498
fprintf(stderr, "Error setting GnuTLS credentials: %s\n",
499
safer_gnutls_strerror(ret));
804
500
gnutls_deinit(*session);
808
504
/* ignore client certificate if any. */
809
gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);
505
gnutls_certificate_server_set_request(*session,
508
gnutls_dh_set_prime_bits(*session, mc.dh_bits);
815
514
static void empty_log(__attribute__((unused)) AvahiLogLevel level,
816
515
__attribute__((unused)) const char *txt){}
818
/* Set effective uid to 0, return errno */
819
__attribute__((warn_unused_result))
820
int raise_privileges(void){
821
int old_errno = errno;
823
if(seteuid(0) == -1){
830
/* Set effective and real user ID to 0. Return errno. */
831
__attribute__((warn_unused_result))
832
int raise_privileges_permanently(void){
833
int old_errno = errno;
834
int ret = raise_privileges();
846
/* Set effective user ID to unprivileged saved user ID */
847
__attribute__((warn_unused_result))
848
int lower_privileges(void){
849
int old_errno = errno;
851
if(seteuid(uid) == -1){
858
/* Lower privileges permanently */
859
__attribute__((warn_unused_result))
860
int lower_privileges_permanently(void){
861
int old_errno = errno;
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);
517
sig_atomic_t quit_now = 0;
518
int signal_received = 0;
1036
520
/* Called when a Mandos server is found */
1037
__attribute__((nonnull, warn_unused_result))
1038
static int start_mandos_communication(const char *ip, in_port_t port,
521
static int start_mandos_communication(const char *ip, uint16_t port,
1039
522
AvahiIfIndex if_index,
1040
int af, mandos_context *mc){
1041
524
int ret, tcp_sd = -1;
1043
struct sockaddr_storage to;
527
struct sockaddr_in in;
528
struct sockaddr_in6 in6;
1044
530
char *buffer = NULL;
1045
char *decrypted_buffer = NULL;
531
char *decrypted_buffer;
1046
532
size_t buffer_length = 0;
1047
533
size_t buffer_capacity = 0;
1050
536
gnutls_session_t session;
1051
537
int pf; /* Protocol family */
1052
bool route_added = false;
1069
fprintf_plus(stderr, "Bad address family: %d\n", af);
551
fprintf(stderr, "Bad address family: %d\n", af);
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);
555
ret = init_gnutls_session(&session);
1112
fprintf_plus(stderr, "Setting up a TCP connection to %s, port %"
1113
PRIuMAX "\n", ip, (uintmax_t)port);
561
fprintf(stderr, "Setting up a TCP connection to %s, port %" PRIu16
1116
tcp_sd = socket(pf, SOCK_STREAM | SOCK_CLOEXEC, 0);
565
tcp_sd = socket(pf, SOCK_STREAM, 0);
1119
perror_plus("socket");
1121
569
goto mandos_end;
1126
573
goto mandos_end;
576
memset(&to, 0, sizeof(to));
1129
577
if(af == AF_INET6){
1130
struct sockaddr_in6 *to6 = (struct sockaddr_in6 *)&to;
1131
*to6 = (struct sockaddr_in6){ .sin6_family = (sa_family_t)af };
1132
ret = inet_pton(af, ip, &to6->sin6_addr);
578
to.in6.sin6_family = (sa_family_t)af;
579
ret = inet_pton(af, ip, &to.in6.sin6_addr);
1133
580
} else { /* IPv4 */
1134
struct sockaddr_in *to4 = (struct sockaddr_in *)&to;
1135
*to4 = (struct sockaddr_in){ .sin_family = (sa_family_t)af };
1136
ret = inet_pton(af, ip, &to4->sin_addr);
581
to.in.sin_family = (sa_family_t)af;
582
ret = inet_pton(af, ip, &to.in.sin_addr);
1140
perror_plus("inet_pton");
1142
587
goto mandos_end;
1146
fprintf_plus(stderr, "Bad address: %s\n", ip);
590
fprintf(stderr, "Bad address: %s\n", ip);
1148
592
goto mandos_end;
1150
594
if(af == AF_INET6){
1151
((struct sockaddr_in6 *)&to)->sin6_port = htons(port);
1152
if(IN6_IS_ADDR_LINKLOCAL
1153
(&((struct sockaddr_in6 *)&to)->sin6_addr)){
595
to.in6.sin6_port = htons(port); /* Spurious warnings from
597
-Wunreachable-code */
599
if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */
600
(&to.in6.sin6_addr)){ /* -Wstrict-aliasing=2 or lower and
1154
602
if(if_index == AVAHI_IF_UNSPEC){
1155
fprintf_plus(stderr, "An IPv6 link-local address is"
1156
" incomplete without a network interface\n");
603
fprintf(stderr, "An IPv6 link-local address is incomplete"
604
" without a network interface\n");
1158
606
goto mandos_end;
1160
608
/* Set the network interface number as scope */
1161
((struct sockaddr_in6 *)&to)->sin6_scope_id = (uint32_t)if_index;
609
to.in6.sin6_scope_id = (uint32_t)if_index;
1164
((struct sockaddr_in *)&to)->sin_port = htons(port);
612
to.in.sin_port = htons(port); /* Spurious warnings from
614
-Wunreachable-code */
1169
618
goto mandos_end;
1173
622
if(af == AF_INET6 and if_index != AVAHI_IF_UNSPEC){
1174
623
char interface[IF_NAMESIZE];
1175
624
if(if_indextoname((unsigned int)if_index, interface) == NULL){
1176
perror_plus("if_indextoname");
625
perror("if_indextoname");
1178
fprintf_plus(stderr, "Connection to: %s%%%s, port %" PRIuMAX
1179
"\n", ip, interface, (uintmax_t)port);
627
fprintf(stderr, "Connection to: %s%%%s, port %" PRIu16 "\n",
628
ip, interface, port);
1182
fprintf_plus(stderr, "Connection to: %s, port %" PRIuMAX "\n",
1183
ip, (uintmax_t)port);
631
fprintf(stderr, "Connection to: %s, port %" PRIu16 "\n", ip,
1185
634
char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?
1186
635
INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";
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
https://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");
638
pcret = inet_ntop(af, &(to.in6.sin6_addr), addrstr,
641
pcret = inet_ntop(af, &(to.in.sin_addr), addrstr,
647
if(strcmp(addrstr, ip) != 0){
648
fprintf(stderr, "Canonical address form: %s\n", addrstr);
658
ret = connect(tcp_sd, &to.in6, sizeof(to));
660
ret = connect(tcp_sd, &to.in, sizeof(to)); /* IPv4 */
1269
672
const char *out = mandos_protocol_version;
1625
966
signal_received = sig;
1626
967
int old_errno = errno;
1627
/* set main loop to exit */
1628
if(simple_poll != NULL){
1629
avahi_simple_poll_quit(simple_poll);
1634
__attribute__((nonnull, warn_unused_result))
1635
bool get_flags(const char *ifname, struct ifreq *ifr){
1639
int s = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1642
perror_plus("socket");
1646
strncpy(ifr->ifr_name, ifname, IF_NAMESIZE);
1647
ifr->ifr_name[IF_NAMESIZE-1] = '\0'; /* NUL terminate */
1648
ret = ioctl(s, SIOCGIFFLAGS, ifr);
1652
perror_plus("ioctl SIOCGIFFLAGS");
1660
__attribute__((nonnull, warn_unused_result))
1661
bool good_flags(const char *ifname, const struct ifreq *ifr){
1663
/* Reject the loopback device */
1664
if(ifr->ifr_flags & IFF_LOOPBACK){
1666
fprintf_plus(stderr, "Rejecting loopback interface \"%s\"\n",
1671
/* Accept point-to-point devices only if connect_to is specified */
1672
if(connect_to != NULL and (ifr->ifr_flags & IFF_POINTOPOINT)){
1674
fprintf_plus(stderr, "Accepting point-to-point interface"
1675
" \"%s\"\n", ifname);
1679
/* Otherwise, reject non-broadcast-capable devices */
1680
if(not (ifr->ifr_flags & IFF_BROADCAST)){
1682
fprintf_plus(stderr, "Rejecting non-broadcast interface"
1683
" \"%s\"\n", ifname);
1687
/* Reject non-ARP interfaces (including dummy interfaces) */
1688
if(ifr->ifr_flags & IFF_NOARP){
1690
fprintf_plus(stderr, "Rejecting non-ARP interface \"%s\"\n",
1696
/* Accept this device */
1698
fprintf_plus(stderr, "Interface \"%s\" is good\n", ifname);
1704
* This function determines if a directory entry in /sys/class/net
1705
* corresponds to an acceptable network device.
1706
* (This function is passed to scandir(3) as a filter function.)
1708
__attribute__((nonnull, warn_unused_result))
1709
int good_interface(const struct dirent *if_entry){
1710
if(if_entry->d_name[0] == '.'){
1715
if(not get_flags(if_entry->d_name, &ifr)){
1717
fprintf_plus(stderr, "Failed to get flags for interface "
1718
"\"%s\"\n", if_entry->d_name);
1723
if(not good_flags(if_entry->d_name, &ifr)){
1730
* This function determines if a network interface is up.
1732
__attribute__((nonnull, warn_unused_result))
1733
bool interface_is_up(const char *interface){
1735
if(not get_flags(interface, &ifr)){
1737
fprintf_plus(stderr, "Failed to get flags for interface "
1738
"\"%s\"\n", interface);
1743
return (bool)(ifr.ifr_flags & IFF_UP);
1747
* This function determines if a network interface is running
1749
__attribute__((nonnull, warn_unused_result))
1750
bool interface_is_running(const char *interface){
1752
if(not get_flags(interface, &ifr)){
1754
fprintf_plus(stderr, "Failed to get flags for interface "
1755
"\"%s\"\n", interface);
1760
return (bool)(ifr.ifr_flags & IFF_RUNNING);
1763
__attribute__((nonnull, pure, warn_unused_result))
1764
int notdotentries(const struct dirent *direntry){
1765
/* Skip "." and ".." */
1766
if(direntry->d_name[0] == '.'
1767
and (direntry->d_name[1] == '\0'
1768
or (direntry->d_name[1] == '.'
1769
and direntry->d_name[2] == '\0'))){
1775
/* Is this directory entry a runnable program? */
1776
__attribute__((nonnull, warn_unused_result))
1777
int runnable_hook(const struct dirent *direntry){
1782
if((direntry->d_name)[0] == '\0'){
1787
sret = strspn(direntry->d_name, "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
1788
"abcdefghijklmnopqrstuvwxyz"
1791
if((direntry->d_name)[sret] != '\0'){
1792
/* Contains non-allowed characters */
1794
fprintf_plus(stderr, "Ignoring hook \"%s\" with bad name\n",
1800
ret = fstatat(hookdir_fd, direntry->d_name, &st, 0);
1803
perror_plus("Could not stat hook");
1807
if(not (S_ISREG(st.st_mode))){
1808
/* Not a regular file */
1810
fprintf_plus(stderr, "Ignoring hook \"%s\" - not a file\n",
1815
if(not (st.st_mode & (S_IXUSR | S_IXGRP | S_IXOTH))){
1816
/* Not executable */
1818
fprintf_plus(stderr, "Ignoring hook \"%s\" - not executable\n",
1824
fprintf_plus(stderr, "Hook \"%s\" is acceptable\n",
1830
__attribute__((nonnull, warn_unused_result))
1831
int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,
1832
mandos_context *mc){
1834
struct timespec now;
1835
struct timespec waited_time;
1836
intmax_t block_time;
1839
if(mc->current_server == NULL){
1841
fprintf_plus(stderr, "Wait until first server is found."
1844
ret = avahi_simple_poll_iterate(s, -1);
1847
fprintf_plus(stderr, "Check current_server if we should run"
1850
/* the current time */
1851
ret = clock_gettime(CLOCK_MONOTONIC, &now);
1853
perror_plus("clock_gettime");
1856
/* Calculating in ms how long time between now and server
1857
who we visted longest time ago. Now - last seen. */
1858
waited_time.tv_sec = (now.tv_sec
1859
- mc->current_server->last_seen.tv_sec);
1860
waited_time.tv_nsec = (now.tv_nsec
1861
- mc->current_server->last_seen.tv_nsec);
1862
/* total time is 10s/10,000ms.
1863
Converting to s from ms by dividing by 1,000,
1864
and ns to ms by dividing by 1,000,000. */
1865
block_time = ((retry_interval
1866
- ((intmax_t)waited_time.tv_sec * 1000))
1867
- ((intmax_t)waited_time.tv_nsec / 1000000));
1870
fprintf_plus(stderr, "Blocking for %" PRIdMAX " ms\n",
1874
if(block_time <= 0){
1875
ret = start_mandos_communication(mc->current_server->ip,
1876
mc->current_server->port,
1877
mc->current_server->if_index,
1878
mc->current_server->af, mc);
1880
avahi_simple_poll_quit(s);
1883
ret = clock_gettime(CLOCK_MONOTONIC,
1884
&mc->current_server->last_seen);
1886
perror_plus("clock_gettime");
1889
mc->current_server = mc->current_server->next;
1890
block_time = 0; /* Call avahi to find new Mandos
1891
servers, but don't block */
1894
ret = avahi_simple_poll_iterate(s, (int)block_time);
1897
if(ret > 0 or errno != EINTR){
1898
return (ret != 1) ? ret : 0;
1904
__attribute__((nonnull))
1905
void run_network_hooks(const char *mode, const char *interface,
1907
struct dirent **direntries = NULL;
1908
if(hookdir_fd == -1){
1909
hookdir_fd = open(hookdir, O_RDONLY | O_DIRECTORY | O_PATH
1911
if(hookdir_fd == -1){
1912
if(errno == ENOENT){
1914
fprintf_plus(stderr, "Network hook directory \"%s\" not"
1915
" found\n", hookdir);
1918
perror_plus("open");
1923
int numhooks = scandirat(hookdir_fd, ".", &direntries,
1924
runnable_hook, alphasort);
1926
perror_plus("scandir");
1929
struct dirent *direntry;
1931
int devnull = (int)TEMP_FAILURE_RETRY(open("/dev/null", O_RDONLY));
1933
perror_plus("open(\"/dev/null\", O_RDONLY)");
1936
for(int i = 0; i < numhooks; i++){
1937
direntry = direntries[i];
1939
fprintf_plus(stderr, "Running network hook \"%s\"\n",
1942
pid_t hook_pid = fork();
1945
/* Raise privileges */
1946
errno = raise_privileges_permanently();
1948
perror_plus("Failed to raise privileges");
1955
perror_plus("setgid");
1958
/* Reset supplementary groups */
1960
ret = setgroups(0, NULL);
1962
perror_plus("setgroups");
1965
ret = setenv("MANDOSNETHOOKDIR", hookdir, 1);
1967
perror_plus("setenv");
1970
ret = setenv("DEVICE", interface, 1);
1972
perror_plus("setenv");
1975
ret = setenv("VERBOSITY", debug ? "1" : "0", 1);
1977
perror_plus("setenv");
1980
ret = setenv("MODE", mode, 1);
1982
perror_plus("setenv");
1986
ret = asprintf(&delaystring, "%f", (double)delay);
1988
perror_plus("asprintf");
1991
ret = setenv("DELAY", delaystring, 1);
1994
perror_plus("setenv");
1998
if(connect_to != NULL){
1999
ret = setenv("CONNECT", connect_to, 1);
2001
perror_plus("setenv");
2005
int hook_fd = (int)TEMP_FAILURE_RETRY(openat(hookdir_fd,
2009
perror_plus("openat");
2010
_exit(EXIT_FAILURE);
2012
if(close(hookdir_fd) == -1){
2013
perror_plus("close");
2014
_exit(EXIT_FAILURE);
2016
ret = dup2(devnull, STDIN_FILENO);
2018
perror_plus("dup2(devnull, STDIN_FILENO)");
2021
ret = close(devnull);
2023
perror_plus("close");
2026
ret = dup2(STDERR_FILENO, STDOUT_FILENO);
2028
perror_plus("dup2(STDERR_FILENO, STDOUT_FILENO)");
2031
if(fexecve(hook_fd, (char *const []){ direntry->d_name, NULL },
2033
perror_plus("fexecve");
2034
_exit(EXIT_FAILURE);
2038
perror_plus("fork");
2043
if(TEMP_FAILURE_RETRY(waitpid(hook_pid, &status, 0)) == -1){
2044
perror_plus("waitpid");
2048
if(WIFEXITED(status)){
2049
if(WEXITSTATUS(status) != 0){
2050
fprintf_plus(stderr, "Warning: network hook \"%s\" exited"
2051
" with status %d\n", direntry->d_name,
2052
WEXITSTATUS(status));
2056
} else if(WIFSIGNALED(status)){
2057
fprintf_plus(stderr, "Warning: network hook \"%s\" died by"
2058
" signal %d\n", direntry->d_name,
2063
fprintf_plus(stderr, "Warning: network hook \"%s\""
2064
" crashed\n", direntry->d_name);
2070
fprintf_plus(stderr, "Network hook \"%s\" ran successfully\n",
2076
if(close(hookdir_fd) == -1){
2077
perror_plus("close");
2084
__attribute__((nonnull, warn_unused_result))
2085
int bring_up_interface(const char *const interface,
2087
int old_errno = errno;
2089
struct ifreq network;
2090
unsigned int if_index = if_nametoindex(interface);
2092
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
2102
if(not interface_is_up(interface)){
2104
int 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");
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 */
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
int take_down_interface(const char *const interface){
2214
int 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)){
2224
int ioctl_errno = 0;
2225
if(not get_flags(interface, &network) and debug){
2227
fprintf_plus(stderr, "Failed to get flags for interface "
2228
"\"%s\"\n", interface);
2232
network.ifr_flags &= ~(short)IFF_UP; /* clear flag */
2234
int sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
2237
perror_plus("socket");
2243
fprintf_plus(stderr, "Taking down interface \"%s\"\n",
2247
/* Raise privileges */
2248
ret_errno = raise_privileges();
2251
perror_plus("Failed to raise privileges");
2254
int ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
2255
ioctl_errno = errno;
2257
/* If raise_privileges() succeeded above */
2259
/* Lower privileges */
2260
ret_errno = lower_privileges();
2263
perror_plus("Failed to lower privileges");
2267
/* Close the socket */
2268
int ret = close(sd);
2270
perror_plus("close");
2273
if(ret_setflags == -1){
2274
errno = ioctl_errno;
2275
perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");
2280
fprintf_plus(stderr, "Interface \"%s\" is already down; odd\n",
968
if(mc.simple_poll != NULL){
969
avahi_simple_poll_quit(mc.simple_poll);
2288
974
int main(int argc, char *argv[]){
2289
mandos_context mc = { .server = NULL, .dh_bits = 0,
2290
.priority = "SECURE256:!CTYPE-X.509"
2291
":+CTYPE-OPENPGP:!RSA:+SIGN-DSA-SHA256",
2292
.current_server = NULL, .interfaces = NULL,
2293
.interfaces_size = 0 };
2294
975
AvahiSServiceBrowser *sb = NULL;
2297
978
intmax_t tmpmax;
2299
980
int exitcode = EXIT_SUCCESS;
2300
char *interfaces_to_take_down = NULL;
2301
size_t interfaces_to_take_down_size = 0;
2302
char run_tempdir[] = "/run/tmp/mandosXXXXXX";
2303
char old_tempdir[] = "/tmp/mandosXXXXXX";
2304
char *tempdir = NULL;
981
const char *interface = "eth0";
982
struct ifreq network;
984
bool take_down_interface = false;
987
char *connect_to = NULL;
988
char tempdir[] = "/tmp/mandosXXXXXX";
989
bool tempdir_created = false;
2305
990
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
2306
991
const char *seckey = PATHDIR "/" SECKEY;
2307
992
const char *pubkey = PATHDIR "/" PUBKEY;
2308
const char *dh_params_file = NULL;
2309
char *interfaces_hooks = NULL;
2311
994
bool gnutls_initialized = false;
2312
995
bool gpgme_initialized = false;
2313
996
float delay = 2.5f;
2314
double retry_interval = 10; /* 10s between trying a server and
2315
retrying the same server again */
2317
struct sigaction old_sigterm_action = { .sa_handler = SIG_DFL };
998
struct sigaction old_sigterm_action;
2318
999
struct sigaction sigterm_action = { .sa_handler = handle_sigterm };
2323
/* Lower any group privileges we might have, just to be safe */
2327
perror_plus("setgid");
2330
/* Lower user privileges (temporarily) */
2334
perror_plus("seteuid");
2342
1002
struct argp_option options[] = {
2343
1003
{ .name = "debug", .key = 128,
2440
1071
delay = strtof(arg, &tmp);
2441
1072
if(errno != 0 or tmp == arg or *tmp != '\0'){
2442
argp_error(state, "Bad delay");
2444
case 132: /* --retry */
2446
retry_interval = strtod(arg, &tmp);
2447
if(errno != 0 or tmp == arg or *tmp != '\0'
2448
or (retry_interval * 1000) > INT_MAX
2449
or retry_interval < 0){
2450
argp_error(state, "Bad retry interval");
2453
case 133: /* --network-hook-dir */
2457
* These reproduce what we would get without ARGP_NO_HELP
2459
case '?': /* --help */
2460
argp_state_help(state, state->out_stream,
2461
(ARGP_HELP_STD_HELP | ARGP_HELP_EXIT_ERR)
2462
& ~(unsigned int)ARGP_HELP_EXIT_OK);
2463
case -3: /* --usage */
2464
argp_state_help(state, state->out_stream,
2465
ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);
2466
case 'V': /* --version */
2467
fprintf_plus(state->out_stream, "%s\n", argp_program_version);
2468
exit(argp_err_exit_status);
1073
fprintf(stderr, "Bad delay\n");
2471
1082
return ARGP_ERR_UNKNOWN;
2476
1087
struct argp argp = { .options = options, .parser = parse_opt,
2477
1088
.args_doc = "",
2478
1089
.doc = "Mandos client -- Get and decrypt"
2479
1090
" passwords from a Mandos server" };
2480
ret_errno = argp_parse(&argp, argc, argv,
2481
ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);
2488
perror_plus("argp_parse");
2489
exitcode = EX_OSERR;
2492
exitcode = EX_USAGE;
2498
/* Work around Debian bug #633582:
2499
<https://bugs.debian.org/633582> */
2501
/* Re-raise privileges */
2502
ret = raise_privileges();
2505
perror_plus("Failed to raise privileges");
2509
if(strcmp(seckey, PATHDIR "/" SECKEY) == 0){
2510
int seckey_fd = open(seckey, O_RDONLY);
2511
if(seckey_fd == -1){
2512
perror_plus("open");
2514
ret = (int)TEMP_FAILURE_RETRY(fstat(seckey_fd, &st));
2516
perror_plus("fstat");
2518
if(S_ISREG(st.st_mode)
2519
and st.st_uid == 0 and st.st_gid == 0){
2520
ret = fchown(seckey_fd, uid, gid);
2522
perror_plus("fchown");
2530
if(strcmp(pubkey, PATHDIR "/" PUBKEY) == 0){
2531
int pubkey_fd = open(pubkey, O_RDONLY);
2532
if(pubkey_fd == -1){
2533
perror_plus("open");
2535
ret = (int)TEMP_FAILURE_RETRY(fstat(pubkey_fd, &st));
2537
perror_plus("fstat");
2539
if(S_ISREG(st.st_mode)
2540
and st.st_uid == 0 and st.st_gid == 0){
2541
ret = fchown(pubkey_fd, uid, gid);
2543
perror_plus("fchown");
2551
if(dh_params_file != NULL
2552
and strcmp(dh_params_file, PATHDIR "/dhparams.pem" ) == 0){
2553
int dhparams_fd = open(dh_params_file, O_RDONLY);
2554
if(dhparams_fd == -1){
2555
perror_plus("open");
2557
ret = (int)TEMP_FAILURE_RETRY(fstat(dhparams_fd, &st));
2559
perror_plus("fstat");
2561
if(S_ISREG(st.st_mode)
2562
and st.st_uid == 0 and st.st_gid == 0){
2563
ret = fchown(dhparams_fd, uid, gid);
2565
perror_plus("fchown");
2573
/* Lower privileges */
2574
ret = lower_privileges();
2577
perror_plus("Failed to lower privileges");
2582
/* Remove invalid interface names (except "none") */
2584
char *interface = NULL;
2585
while((interface = argz_next(mc.interfaces, mc.interfaces_size,
2587
if(strcmp(interface, "none") != 0
2588
and if_nametoindex(interface) == 0){
2589
if(interface[0] != '\0'){
2590
fprintf_plus(stderr, "Not using nonexisting interface"
2591
" \"%s\"\n", interface);
2593
argz_delete(&mc.interfaces, &mc.interfaces_size, interface);
2599
/* Run network hooks */
2601
if(mc.interfaces != NULL){
2602
interfaces_hooks = malloc(mc.interfaces_size);
2603
if(interfaces_hooks == NULL){
2604
perror_plus("malloc");
2607
memcpy(interfaces_hooks, mc.interfaces, mc.interfaces_size);
2608
argz_stringify(interfaces_hooks, mc.interfaces_size, (int)',');
2610
run_network_hooks("start", interfaces_hooks != NULL ?
2611
interfaces_hooks : "", delay);
1091
ret = argp_parse(&argp, argc, argv, 0, 0, NULL);
1092
if(ret == ARGP_ERR_UNKNOWN){
1093
fprintf(stderr, "Unknown error while parsing arguments\n");
1094
exitcode = EXIT_FAILURE;
2653
1137
ret = sigaction(SIGINT, NULL, &old_sigterm_action);
2655
perror_plus("sigaction");
1139
perror("sigaction");
1140
return EXIT_FAILURE;
2658
1142
if(old_sigterm_action.sa_handler != SIG_IGN){
2659
1143
ret = sigaction(SIGINT, &sigterm_action, NULL);
2661
perror_plus("sigaction");
2662
exitcode = EX_OSERR;
1145
perror("sigaction");
1146
exitcode = EXIT_FAILURE;
2666
1150
ret = sigaction(SIGHUP, NULL, &old_sigterm_action);
2668
perror_plus("sigaction");
1152
perror("sigaction");
1153
return EXIT_FAILURE;
2671
1155
if(old_sigterm_action.sa_handler != SIG_IGN){
2672
1156
ret = sigaction(SIGHUP, &sigterm_action, NULL);
2674
perror_plus("sigaction");
2675
exitcode = EX_OSERR;
1158
perror("sigaction");
1159
exitcode = EXIT_FAILURE;
2679
1163
ret = sigaction(SIGTERM, NULL, &old_sigterm_action);
2681
perror_plus("sigaction");
1165
perror("sigaction");
1166
return EXIT_FAILURE;
2684
1168
if(old_sigterm_action.sa_handler != SIG_IGN){
2685
1169
ret = sigaction(SIGTERM, &sigterm_action, NULL);
2687
perror_plus("sigaction");
2688
exitcode = EX_OSERR;
2693
/* If no interfaces were specified, make a list */
2694
if(mc.interfaces == NULL){
2695
struct dirent **direntries = NULL;
2696
/* Look for any good interfaces */
2697
ret = scandir(sys_class_net, &direntries, good_interface,
2700
/* Add all found interfaces to interfaces list */
2701
for(int i = 0; i < ret; ++i){
2702
ret_errno = argz_add(&mc.interfaces, &mc.interfaces_size,
2703
direntries[i]->d_name);
2706
perror_plus("argz_add");
2707
free(direntries[i]);
2711
fprintf_plus(stderr, "Will use interface \"%s\"\n",
2712
direntries[i]->d_name);
2714
free(direntries[i]);
2721
fprintf_plus(stderr, "Could not find a network interface\n");
2722
exitcode = EXIT_FAILURE;
2727
/* Bring up interfaces which are down, and remove any "none"s */
2729
char *interface = NULL;
2730
while((interface = argz_next(mc.interfaces, mc.interfaces_size,
2732
/* If interface name is "none", stop bringing up interfaces.
2733
Also remove all instances of "none" from the list */
2734
if(strcmp(interface, "none") == 0){
2735
argz_delete(&mc.interfaces, &mc.interfaces_size,
2738
while((interface = argz_next(mc.interfaces,
2739
mc.interfaces_size, interface))){
2740
if(strcmp(interface, "none") == 0){
2741
argz_delete(&mc.interfaces, &mc.interfaces_size,
1171
perror("sigaction");
1172
exitcode = EXIT_FAILURE;
1177
/* If the interface is down, bring it up */
1178
if(interface[0] != '\0'){
1179
if_index = (AvahiIfIndex) if_nametoindex(interface);
1181
fprintf(stderr, "No such interface: \"%s\"\n", interface);
1182
exitcode = EXIT_FAILURE;
1191
/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO
1192
messages to mess up the prompt */
1193
ret = klogctl(8, NULL, 5);
1194
bool restore_loglevel = true;
1196
restore_loglevel = false;
1199
#endif /* __linux__ */
1201
sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1204
exitcode = EXIT_FAILURE;
1206
if(restore_loglevel){
1207
ret = klogctl(7, NULL, 0);
1212
#endif /* __linux__ */
1215
strcpy(network.ifr_name, interface);
1216
ret = ioctl(sd, SIOCGIFFLAGS, &network);
1218
perror("ioctl SIOCGIFFLAGS");
1220
if(restore_loglevel){
1221
ret = klogctl(7, NULL, 0);
1226
#endif /* __linux__ */
1227
exitcode = EXIT_FAILURE;
1230
if((network.ifr_flags & IFF_UP) == 0){
1231
network.ifr_flags |= IFF_UP;
1232
take_down_interface = true;
1233
ret = ioctl(sd, SIOCSIFFLAGS, &network);
1235
take_down_interface = false;
1236
perror("ioctl SIOCSIFFLAGS");
1237
exitcode = EXIT_FAILURE;
1239
if(restore_loglevel){
1240
ret = klogctl(7, NULL, 0);
1245
#endif /* __linux__ */
1249
/* sleep checking until interface is running */
1250
for(int i=0; i < delay * 4; i++){
1251
ret = ioctl(sd, SIOCGIFFLAGS, &network);
1253
perror("ioctl SIOCGIFFLAGS");
1254
} else if(network.ifr_flags & IFF_RUNNING){
2748
bool interface_was_up = interface_is_up(interface);
2749
errno = bring_up_interface(interface, delay);
2750
if(not interface_was_up){
2752
fprintf_plus(stderr, "Failed to bring up interface \"%s\":"
2753
" %s\n", interface, strerror(errno));
2755
errno = argz_add(&interfaces_to_take_down,
2756
&interfaces_to_take_down_size,
2759
perror_plus("argz_add");
2764
if(debug and (interfaces_to_take_down == NULL)){
2765
fprintf_plus(stderr, "No interfaces were brought up\n");
2769
/* If we only got one interface, explicitly use only that one */
2770
if(argz_count(mc.interfaces, mc.interfaces_size) == 1){
2772
fprintf_plus(stderr, "Using only interface \"%s\"\n",
2775
if_index = (AvahiIfIndex)if_nametoindex(mc.interfaces);
2782
ret = init_gnutls_global(pubkey, seckey, dh_params_file, &mc);
2784
fprintf_plus(stderr, "init_gnutls_global failed\n");
2785
exitcode = EX_UNAVAILABLE;
1257
struct timespec sleeptime = { .tv_nsec = 250000000 };
1258
ret = nanosleep(&sleeptime, NULL);
1259
if(ret == -1 and errno != EINTR){
1260
perror("nanosleep");
1263
if(not take_down_interface){
1264
/* We won't need the socket anymore */
1265
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1271
if(restore_loglevel){
1272
/* Restores kernel loglevel to default */
1273
ret = klogctl(7, NULL, 0);
1278
#endif /* __linux__ */
1288
/* Drop any group privileges we might have, just to be safe */
1295
/* Drop user privileges */
1297
/* Will we need privileges later? */
1298
if(take_down_interface){
1299
/* Drop user privileges temporarily */
1305
/* Drop user privileges permanently */
1316
ret = init_gnutls_global(pubkey, seckey);
1318
fprintf(stderr, "init_gnutls_global failed\n");
1319
exitcode = EXIT_FAILURE;
2788
1322
gnutls_initialized = true;
2981
1484
gpgme_release(mc.ctx);
2984
/* Cleans up the circular linked list of Mandos servers the client
2986
if(mc.current_server != NULL){
2987
mc.current_server->prev->next = NULL;
2988
while(mc.current_server != NULL){
2989
server *next = mc.current_server->next;
2991
#pragma GCC diagnostic push
2992
#pragma GCC diagnostic ignored "-Wcast-qual"
2994
free((char *)(mc.current_server->ip));
2996
#pragma GCC diagnostic pop
2998
free(mc.current_server);
2999
mc.current_server = next;
3003
/* Re-raise privileges */
3005
ret = raise_privileges();
3008
perror_plus("Failed to raise privileges");
3011
/* Run network hooks */
3012
run_network_hooks("stop", interfaces_hooks != NULL ?
3013
interfaces_hooks : "", delay);
3015
/* Take down the network interfaces which were brought up */
3017
char *interface = NULL;
3018
while((interface=argz_next(interfaces_to_take_down,
3019
interfaces_to_take_down_size,
3021
ret = take_down_interface(interface);
3024
perror_plus("Failed to take down interface");
3027
if(debug and (interfaces_to_take_down == NULL)){
3028
fprintf_plus(stderr, "No interfaces needed to be taken"
3034
ret = lower_privileges_permanently();
3037
perror_plus("Failed to lower privileges permanently");
3041
free(interfaces_to_take_down);
3042
free(interfaces_hooks);
3044
void clean_dir_at(int base, const char * const dirname,
3046
struct dirent **direntries = NULL;
3048
int dir_fd = (int)TEMP_FAILURE_RETRY(openat(base, dirname,
3054
perror_plus("open");
3056
int numentries = scandirat(dir_fd, ".", &direntries,
3057
notdotentries, alphasort);
3058
if(numentries >= 0){
3059
for(int i = 0; i < numentries; i++){
3061
fprintf_plus(stderr, "Unlinking \"%s/%s\"\n",
3062
dirname, direntries[i]->d_name);
3064
dret = unlinkat(dir_fd, direntries[i]->d_name, 0);
3066
if(errno == EISDIR){
3067
dret = unlinkat(dir_fd, direntries[i]->d_name,
3070
if((dret == -1) and (errno == ENOTEMPTY)
3071
and (strcmp(direntries[i]->d_name, "private-keys-v1.d")
3072
== 0) and (level == 0)){
3073
/* Recurse only in this special case */
3074
clean_dir_at(dir_fd, direntries[i]->d_name, level+1);
3078
fprintf_plus(stderr, "unlink(\"%s/%s\"): %s\n", dirname,
3079
direntries[i]->d_name, strerror(errno));
3082
free(direntries[i]);
3085
/* need to clean even if 0 because man page doesn't specify */
3087
if(numentries == -1){
3088
perror_plus("scandirat");
3090
dret = unlinkat(base, dirname, AT_REMOVEDIR);
3091
if(dret == -1 and errno != ENOENT){
3092
perror_plus("rmdir");
3095
perror_plus("scandirat");
3100
/* Removes the GPGME temp directory and all files inside */
3101
if(tempdir != NULL){
3102
clean_dir_at(-1, tempdir, 0);
1487
/* Take down the network interface */
1488
if(take_down_interface){
1489
/* Re-raise priviliges */
1496
ret = ioctl(sd, SIOCGIFFLAGS, &network);
1498
perror("ioctl SIOCGIFFLAGS");
1499
} else if(network.ifr_flags & IFF_UP) {
1500
network.ifr_flags &= ~IFF_UP; /* clear flag */
1501
ret = ioctl(sd, SIOCSIFFLAGS, &network);
1503
perror("ioctl SIOCSIFFLAGS");
1506
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1510
/* Lower privileges, permanently this time */
1519
/* Removes the temp directory used by GPGME */
1520
if(tempdir_created){
1522
struct dirent *direntry;
1523
d = opendir(tempdir);
1525
if(errno != ENOENT){
1530
direntry = readdir(d);
1531
if(direntry == NULL){
1534
/* Skip "." and ".." */
1535
if(direntry->d_name[0] == '.'
1536
and (direntry->d_name[1] == '\0'
1537
or (direntry->d_name[1] == '.'
1538
and direntry->d_name[2] == '\0'))){
1541
char *fullname = NULL;
1542
ret = asprintf(&fullname, "%s/%s", tempdir,
1548
ret = remove(fullname);
1550
fprintf(stderr, "remove(\"%s\"): %s\n", fullname,
1557
ret = rmdir(tempdir);
1558
if(ret == -1 and errno != ENOENT){
3106
1564
sigemptyset(&old_sigterm_action.sa_mask);
3107
1565
old_sigterm_action.sa_handler = SIG_DFL;
3108
ret = (int)TEMP_FAILURE_RETRY(sigaction(signal_received,
3109
&old_sigterm_action,
1566
ret = sigaction(signal_received, &old_sigterm_action, NULL);
3112
perror_plus("sigaction");
3115
ret = raise(signal_received);
3116
} while(ret != 0 and errno == EINTR);
3118
perror_plus("raise");
3121
TEMP_FAILURE_RETRY(pause());
1568
perror("sigaction");
1570
raise(signal_received);
3124
1573
return exitcode;