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
#include <stdlib.h> /* free(), EXIT_SUCCESS, EXIT_FAILURE,
47
srand(), strtof(), abort() */
46
#include <stdlib.h> /* free(), EXIT_SUCCESS, srand(),
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() */
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 */
66
#include <time.h> /* nanosleep(), time() */
65
#include <errno.h> /* perror(), errno,
66
program_invocation_short_name */
67
#include <time.h> /* nanosleep(), time(), sleep() */
67
68
#include <net/if.h> /* ioctl, ifreq, SIOCGIFFLAGS, IFF_UP,
68
69
SIOCSIFFLAGS, if_indextoname(),
69
70
if_nametoindex(), IF_NAMESIZE */
120
133
#define PATHDIR "/conf/conf.d/mandos"
121
134
#define SECKEY "seckey.txt"
122
135
#define PUBKEY "pubkey.txt"
136
#define HOOKDIR "/lib/mandos/network-hooks.d"
124
138
bool debug = false;
125
139
static const char mandos_protocol_version[] = "1";
126
140
const char *argp_program_version = "mandos-client " VERSION;
127
const char *argp_program_bug_address = "<mandos@fukt.bsnet.se>";
141
const char *argp_program_bug_address = "<mandos@recompile.se>";
128
142
static const char sys_class_net[] = "/sys/class/net";
129
143
char *connect_to = NULL;
144
const char *hookdir = HOOKDIR;
149
/* Doubly linked list that need to be circularly linked when used */
150
typedef struct server{
153
AvahiIfIndex if_index;
155
struct timespec last_seen;
131
160
/* Used for passing in values through the Avahi callback functions */
133
AvahiSimplePoll *simple_poll;
134
162
AvahiServer *server;
135
163
gnutls_certificate_credentials_t cred;
136
164
unsigned int dh_bits;
137
165
gnutls_dh_params_t dh_params;
138
166
const char *priority;
168
server *current_server;
170
size_t interfaces_size;
140
171
} mandos_context;
142
/* global context so signal handler can reach it*/
143
mandos_context mc = { .simple_poll = NULL, .server = NULL,
144
.dh_bits = 1024, .priority = "SECURE256"
145
":!CTYPE-X.509:+CTYPE-OPENPGP" };
173
/* global so signal handler can reach it*/
174
AvahiSimplePoll *simple_poll;
147
176
sig_atomic_t quit_now = 0;
148
177
int signal_received = 0;
179
/* Function to use when printing errors */
180
void perror_plus(const char *print_text){
182
fprintf(stderr, "Mandos plugin %s: ",
183
program_invocation_short_name);
188
__attribute__((format (gnu_printf, 2, 3), nonnull))
189
int fprintf_plus(FILE *stream, const char *format, ...){
191
va_start (ap, format);
193
TEMP_FAILURE_RETRY(fprintf(stream, "Mandos plugin %s: ",
194
program_invocation_short_name));
195
return (int)TEMP_FAILURE_RETRY(vfprintf(stream, format, ap));
151
199
* Make additional room in "buffer" for at least BUFFER_SIZE more
152
200
* bytes. "buffer_capacity" is how much is currently allocated,
153
201
* "buffer_length" is how much is already used.
203
__attribute__((nonnull, warn_unused_result))
155
204
size_t incbuffer(char **buffer, size_t buffer_length,
156
size_t buffer_capacity){
205
size_t buffer_capacity){
157
206
if(buffer_length + BUFFER_SIZE > buffer_capacity){
158
*buffer = realloc(*buffer, buffer_capacity + BUFFER_SIZE);
207
char *new_buf = realloc(*buffer, buffer_capacity + BUFFER_SIZE);
209
int old_errno = errno;
162
216
buffer_capacity += BUFFER_SIZE;
164
218
return buffer_capacity;
221
/* Add server to set of servers to retry periodically */
222
__attribute__((nonnull, warn_unused_result))
223
bool add_server(const char *ip, in_port_t port, AvahiIfIndex if_index,
224
int af, server **current_server){
226
server *new_server = malloc(sizeof(server));
227
if(new_server == NULL){
228
perror_plus("malloc");
231
*new_server = (server){ .ip = strdup(ip),
233
.if_index = if_index,
235
if(new_server->ip == NULL){
236
perror_plus("strdup");
240
ret = clock_gettime(CLOCK_MONOTONIC, &(new_server->last_seen));
242
perror_plus("clock_gettime");
244
#pragma GCC diagnostic push
245
#pragma GCC diagnostic ignored "-Wcast-qual"
247
free((char *)(new_server->ip));
249
#pragma GCC diagnostic pop
254
/* Special case of first server */
255
if(*current_server == NULL){
256
new_server->next = new_server;
257
new_server->prev = new_server;
258
*current_server = new_server;
260
/* Place the new server last in the list */
261
new_server->next = *current_server;
262
new_server->prev = (*current_server)->prev;
263
new_server->prev->next = new_server;
264
(*current_server)->prev = new_server;
168
270
* Initialize GPGME.
170
static bool init_gpgme(const char *seckey,
171
const char *pubkey, const char *tempdir){
272
__attribute__((nonnull, warn_unused_result))
273
static bool init_gpgme(const char * const seckey,
274
const char * const pubkey,
275
const char * const tempdir,
172
277
gpgme_error_t rc;
173
278
gpgme_engine_info_t engine_info;
177
281
* Helper function to insert pub and seckey to the engine keyring.
179
bool import_key(const char *filename){
283
bool import_key(const char * const filename){
182
286
gpgme_data_t pgp_data;
184
288
fd = (int)TEMP_FAILURE_RETRY(open(filename, O_RDONLY));
190
294
rc = gpgme_data_new_from_fd(&pgp_data, fd);
191
295
if(rc != GPG_ERR_NO_ERROR){
192
fprintf(stderr, "bad gpgme_data_new_from_fd: %s: %s\n",
193
gpgme_strsource(rc), gpgme_strerror(rc));
296
fprintf_plus(stderr, "bad gpgme_data_new_from_fd: %s: %s\n",
297
gpgme_strsource(rc), gpgme_strerror(rc));
197
rc = gpgme_op_import(mc.ctx, pgp_data);
301
rc = gpgme_op_import(mc->ctx, pgp_data);
198
302
if(rc != GPG_ERR_NO_ERROR){
199
fprintf(stderr, "bad gpgme_op_import: %s: %s\n",
200
gpgme_strsource(rc), gpgme_strerror(rc));
303
fprintf_plus(stderr, "bad gpgme_op_import: %s: %s\n",
304
gpgme_strsource(rc), gpgme_strerror(rc));
204
ret = (int)TEMP_FAILURE_RETRY(close(fd));
310
perror_plus("close");
208
312
gpgme_data_release(pgp_data);
213
fprintf(stderr, "Initializing GPGME\n");
317
fprintf_plus(stderr, "Initializing GPGME\n");
217
321
gpgme_check_version(NULL);
218
322
rc = gpgme_engine_check_version(GPGME_PROTOCOL_OpenPGP);
219
323
if(rc != GPG_ERR_NO_ERROR){
220
fprintf(stderr, "bad gpgme_engine_check_version: %s: %s\n",
221
gpgme_strsource(rc), gpgme_strerror(rc));
324
fprintf_plus(stderr, "bad gpgme_engine_check_version: %s: %s\n",
325
gpgme_strsource(rc), gpgme_strerror(rc));
225
/* Set GPGME home directory for the OpenPGP engine only */
329
/* Set GPGME home directory for the OpenPGP engine only */
226
330
rc = gpgme_get_engine_info(&engine_info);
227
331
if(rc != GPG_ERR_NO_ERROR){
228
fprintf(stderr, "bad gpgme_get_engine_info: %s: %s\n",
229
gpgme_strsource(rc), gpgme_strerror(rc));
332
fprintf_plus(stderr, "bad gpgme_get_engine_info: %s: %s\n",
333
gpgme_strsource(rc), gpgme_strerror(rc));
232
336
while(engine_info != NULL){
271
379
ssize_t plaintext_length = 0;
274
fprintf(stderr, "Trying to decrypt OpenPGP data\n");
382
fprintf_plus(stderr, "Trying to decrypt OpenPGP data\n");
277
385
/* Create new GPGME data buffer from memory cryptotext */
278
386
rc = gpgme_data_new_from_mem(&dh_crypto, cryptotext, crypto_size,
280
388
if(rc != GPG_ERR_NO_ERROR){
281
fprintf(stderr, "bad gpgme_data_new_from_mem: %s: %s\n",
282
gpgme_strsource(rc), gpgme_strerror(rc));
389
fprintf_plus(stderr, "bad gpgme_data_new_from_mem: %s: %s\n",
390
gpgme_strsource(rc), gpgme_strerror(rc));
286
394
/* Create new empty GPGME data buffer for the plaintext */
287
395
rc = gpgme_data_new(&dh_plain);
288
396
if(rc != GPG_ERR_NO_ERROR){
289
fprintf(stderr, "bad gpgme_data_new: %s: %s\n",
290
gpgme_strsource(rc), gpgme_strerror(rc));
397
fprintf_plus(stderr, "Mandos plugin mandos-client: "
398
"bad gpgme_data_new: %s: %s\n",
399
gpgme_strsource(rc), gpgme_strerror(rc));
291
400
gpgme_data_release(dh_crypto);
295
404
/* Decrypt data from the cryptotext data buffer to the plaintext
297
rc = gpgme_op_decrypt(mc.ctx, dh_crypto, dh_plain);
406
rc = gpgme_op_decrypt(mc->ctx, dh_crypto, dh_plain);
298
407
if(rc != GPG_ERR_NO_ERROR){
299
fprintf(stderr, "bad gpgme_op_decrypt: %s: %s\n",
300
gpgme_strsource(rc), gpgme_strerror(rc));
408
fprintf_plus(stderr, "bad gpgme_op_decrypt: %s: %s\n",
409
gpgme_strsource(rc), gpgme_strerror(rc));
301
410
plaintext_length = -1;
303
412
gpgme_decrypt_result_t result;
304
result = gpgme_op_decrypt_result(mc.ctx);
413
result = gpgme_op_decrypt_result(mc->ctx);
305
414
if(result == NULL){
306
fprintf(stderr, "gpgme_op_decrypt_result failed\n");
415
fprintf_plus(stderr, "gpgme_op_decrypt_result failed\n");
308
fprintf(stderr, "Unsupported algorithm: %s\n",
309
result->unsupported_algorithm);
310
fprintf(stderr, "Wrong key usage: %u\n",
311
result->wrong_key_usage);
417
fprintf_plus(stderr, "Unsupported algorithm: %s\n",
418
result->unsupported_algorithm);
419
fprintf_plus(stderr, "Wrong key usage: %u\n",
420
result->wrong_key_usage);
312
421
if(result->file_name != NULL){
313
fprintf(stderr, "File name: %s\n", result->file_name);
422
fprintf_plus(stderr, "File name: %s\n", result->file_name);
315
424
gpgme_recipient_t recipient;
316
425
recipient = result->recipients;
317
426
while(recipient != NULL){
318
fprintf(stderr, "Public key algorithm: %s\n",
319
gpgme_pubkey_algo_name(recipient->pubkey_algo));
320
fprintf(stderr, "Key ID: %s\n", recipient->keyid);
321
fprintf(stderr, "Secret key available: %s\n",
322
recipient->status == GPG_ERR_NO_SECKEY
427
fprintf_plus(stderr, "Public key algorithm: %s\n",
428
gpgme_pubkey_algo_name
429
(recipient->pubkey_algo));
430
fprintf_plus(stderr, "Key ID: %s\n", recipient->keyid);
431
fprintf_plus(stderr, "Secret key available: %s\n",
432
recipient->status == GPG_ERR_NO_SECKEY
324
434
recipient = recipient->next;
423
543
/* OpenPGP credentials */
424
gnutls_certificate_allocate_credentials(&mc.cred);
544
ret = gnutls_certificate_allocate_credentials(&mc->cred);
425
545
if(ret != GNUTLS_E_SUCCESS){
426
fprintf(stderr, "GnuTLS memory error: %s\n", /* Spurious warning
430
safer_gnutls_strerror(ret));
546
fprintf_plus(stderr, "GnuTLS memory error: %s\n",
547
safer_gnutls_strerror(ret));
431
548
gnutls_global_deinit();
436
fprintf(stderr, "Attempting to use OpenPGP public key %s and"
437
" secret key %s as GnuTLS credentials\n", pubkeyfilename,
553
fprintf_plus(stderr, "Attempting to use OpenPGP public key %s and"
554
" secret key %s as GnuTLS credentials\n",
441
559
ret = gnutls_certificate_set_openpgp_key_file
442
(mc.cred, pubkeyfilename, seckeyfilename,
560
(mc->cred, pubkeyfilename, seckeyfilename,
443
561
GNUTLS_OPENPGP_FMT_BASE64);
444
562
if(ret != GNUTLS_E_SUCCESS){
446
"Error[%d] while reading the OpenPGP key pair ('%s',"
447
" '%s')\n", ret, pubkeyfilename, seckeyfilename);
448
fprintf(stderr, "The GnuTLS error is: %s\n",
449
safer_gnutls_strerror(ret));
564
"Error[%d] while reading the OpenPGP key pair ('%s',"
565
" '%s')\n", ret, pubkeyfilename, seckeyfilename);
566
fprintf_plus(stderr, "The GnuTLS error is: %s\n",
567
safer_gnutls_strerror(ret));
453
571
/* GnuTLS server initialization */
454
ret = gnutls_dh_params_init(&mc.dh_params);
455
if(ret != GNUTLS_E_SUCCESS){
456
fprintf(stderr, "Error in GnuTLS DH parameter initialization:"
457
" %s\n", safer_gnutls_strerror(ret));
460
ret = gnutls_dh_params_generate2(mc.dh_params, mc.dh_bits);
461
if(ret != GNUTLS_E_SUCCESS){
462
fprintf(stderr, "Error in GnuTLS prime generation: %s\n",
463
safer_gnutls_strerror(ret));
467
gnutls_certificate_set_dh_params(mc.cred, mc.dh_params);
572
ret = gnutls_dh_params_init(&mc->dh_params);
573
if(ret != GNUTLS_E_SUCCESS){
574
fprintf_plus(stderr, "Error in GnuTLS DH parameter"
575
" initialization: %s\n",
576
safer_gnutls_strerror(ret));
579
/* If a Diffie-Hellman parameters file was given, try to use it */
580
if(dhparamsfilename != NULL){
581
gnutls_datum_t params = { .data = NULL, .size = 0 };
583
int dhpfile = open(dhparamsfilename, O_RDONLY);
586
dhparamsfilename = NULL;
589
size_t params_capacity = 0;
591
params_capacity = incbuffer((char **)¶ms.data,
593
(size_t)params_capacity);
594
if(params_capacity == 0){
595
perror_plus("incbuffer");
598
dhparamsfilename = NULL;
601
ssize_t bytes_read = read(dhpfile,
602
params.data + params.size,
608
/* check bytes_read for failure */
613
dhparamsfilename = NULL;
616
params.size += (unsigned int)bytes_read;
618
if(params.data == NULL){
619
dhparamsfilename = NULL;
621
if(dhparamsfilename == NULL){
624
ret = gnutls_dh_params_import_pkcs3(mc->dh_params, ¶ms,
625
GNUTLS_X509_FMT_PEM);
626
if(ret != GNUTLS_E_SUCCESS){
627
fprintf_plus(stderr, "Failed to parse DH parameters in file"
628
" \"%s\": %s\n", dhparamsfilename,
629
safer_gnutls_strerror(ret));
630
dhparamsfilename = NULL;
634
if(dhparamsfilename == NULL){
635
if(mc->dh_bits == 0){
636
/* Find out the optimal number of DH bits */
637
/* Try to read the private key file */
638
gnutls_datum_t buffer = { .data = NULL, .size = 0 };
640
int secfile = open(seckeyfilename, O_RDONLY);
645
size_t buffer_capacity = 0;
647
buffer_capacity = incbuffer((char **)&buffer.data,
649
(size_t)buffer_capacity);
650
if(buffer_capacity == 0){
651
perror_plus("incbuffer");
656
ssize_t bytes_read = read(secfile,
657
buffer.data + buffer.size,
663
/* check bytes_read for failure */
670
buffer.size += (unsigned int)bytes_read;
674
/* If successful, use buffer to parse private key */
675
gnutls_sec_param_t sec_param = GNUTLS_SEC_PARAM_ULTRA;
676
if(buffer.data != NULL){
678
gnutls_openpgp_privkey_t privkey = NULL;
679
ret = gnutls_openpgp_privkey_init(&privkey);
680
if(ret != GNUTLS_E_SUCCESS){
681
fprintf_plus(stderr, "Error initializing OpenPGP key"
683
safer_gnutls_strerror(ret));
687
ret = gnutls_openpgp_privkey_import
688
(privkey, &buffer, GNUTLS_OPENPGP_FMT_BASE64, "", 0);
689
if(ret != GNUTLS_E_SUCCESS){
690
fprintf_plus(stderr, "Error importing OpenPGP key : %s",
691
safer_gnutls_strerror(ret));
697
/* Use private key to suggest an appropriate
699
sec_param = gnutls_openpgp_privkey_sec_param(privkey);
700
gnutls_openpgp_privkey_deinit(privkey);
702
fprintf_plus(stderr, "This OpenPGP key implies using"
703
" a GnuTLS security parameter \"%s\".\n",
704
safe_string(gnutls_sec_param_get_name
710
if(sec_param == GNUTLS_SEC_PARAM_UNKNOWN){
711
/* Err on the side of caution */
712
sec_param = GNUTLS_SEC_PARAM_ULTRA;
714
fprintf_plus(stderr, "Falling back to security parameter"
716
safe_string(gnutls_sec_param_get_name
721
uret = gnutls_sec_param_to_pk_bits(GNUTLS_PK_DH, sec_param);
725
fprintf_plus(stderr, "A \"%s\" GnuTLS security parameter"
726
" implies %u DH bits; using that.\n",
727
safe_string(gnutls_sec_param_get_name
732
fprintf_plus(stderr, "Failed to get implied number of DH"
733
" bits for security parameter \"%s\"): %s\n",
734
safe_string(gnutls_sec_param_get_name
736
safer_gnutls_strerror(ret));
740
fprintf_plus(stderr, "DH bits explicitly set to %u\n",
743
ret = gnutls_dh_params_generate2(mc->dh_params, mc->dh_bits);
744
if(ret != GNUTLS_E_SUCCESS){
745
fprintf_plus(stderr, "Error in GnuTLS prime generation (%u"
746
" bits): %s\n", mc->dh_bits,
747
safer_gnutls_strerror(ret));
751
gnutls_certificate_set_dh_params(mc->cred, mc->dh_params);
473
gnutls_certificate_free_credentials(mc.cred);
757
gnutls_certificate_free_credentials(mc->cred);
474
758
gnutls_global_deinit();
475
gnutls_dh_params_deinit(mc.dh_params);
759
gnutls_dh_params_deinit(mc->dh_params);
479
static int init_gnutls_session(gnutls_session_t *session){
763
__attribute__((nonnull, warn_unused_result))
764
static int init_gnutls_session(gnutls_session_t *session,
481
767
/* GnuTLS session creation */
535
820
static void empty_log(__attribute__((unused)) AvahiLogLevel level,
536
821
__attribute__((unused)) const char *txt){}
823
/* Set effective uid to 0, return errno */
824
__attribute__((warn_unused_result))
825
error_t raise_privileges(void){
826
error_t old_errno = errno;
827
error_t ret_errno = 0;
828
if(seteuid(0) == -1){
835
/* Set effective and real user ID to 0. Return errno. */
836
__attribute__((warn_unused_result))
837
error_t raise_privileges_permanently(void){
838
error_t old_errno = errno;
839
error_t ret_errno = raise_privileges();
851
/* Set effective user ID to unprivileged saved user ID */
852
__attribute__((warn_unused_result))
853
error_t lower_privileges(void){
854
error_t old_errno = errno;
855
error_t ret_errno = 0;
856
if(seteuid(uid) == -1){
863
/* Lower privileges permanently */
864
__attribute__((warn_unused_result))
865
error_t lower_privileges_permanently(void){
866
error_t old_errno = errno;
867
error_t ret_errno = 0;
868
if(setuid(uid) == -1){
875
/* Helper function to add_local_route() and delete_local_route() */
876
__attribute__((nonnull, warn_unused_result))
877
static bool add_delete_local_route(const bool add,
879
AvahiIfIndex if_index){
881
char helper[] = "mandos-client-iprouteadddel";
882
char add_arg[] = "add";
883
char delete_arg[] = "delete";
884
char debug_flag[] = "--debug";
885
char *pluginhelperdir = getenv("MANDOSPLUGINHELPERDIR");
886
if(pluginhelperdir == NULL){
888
fprintf_plus(stderr, "MANDOSPLUGINHELPERDIR environment"
889
" variable not set; cannot run helper\n");
894
char interface[IF_NAMESIZE];
895
if(if_indextoname((unsigned int)if_index, interface) == NULL){
896
perror_plus("if_indextoname");
900
int devnull = (int)TEMP_FAILURE_RETRY(open("/dev/null", O_RDONLY));
902
perror_plus("open(\"/dev/null\", O_RDONLY)");
908
/* Raise privileges */
909
errno = raise_privileges_permanently();
911
perror_plus("Failed to raise privileges");
912
/* _exit(EX_NOPERM); */
918
perror_plus("setgid");
921
/* Reset supplementary groups */
923
ret = setgroups(0, NULL);
925
perror_plus("setgroups");
929
ret = dup2(devnull, STDIN_FILENO);
931
perror_plus("dup2(devnull, STDIN_FILENO)");
934
ret = close(devnull);
936
perror_plus("close");
939
ret = dup2(STDERR_FILENO, STDOUT_FILENO);
941
perror_plus("dup2(STDERR_FILENO, STDOUT_FILENO)");
944
int helperdir_fd = (int)TEMP_FAILURE_RETRY(open(pluginhelperdir,
949
if(helperdir_fd == -1){
951
_exit(EX_UNAVAILABLE);
953
int helper_fd = (int)TEMP_FAILURE_RETRY(openat(helperdir_fd,
956
perror_plus("openat");
958
_exit(EX_UNAVAILABLE);
962
#pragma GCC diagnostic push
963
#pragma GCC diagnostic ignored "-Wcast-qual"
965
if(fexecve(helper_fd, (char *const [])
966
{ helper, add ? add_arg : delete_arg, (char *)address,
967
interface, debug ? debug_flag : NULL, NULL },
970
#pragma GCC diagnostic pop
972
perror_plus("fexecve");
984
pret = waitpid(pid, &status, 0);
985
if(pret == -1 and errno == EINTR and quit_now){
986
int errno_raising = 0;
987
if((errno = raise_privileges()) != 0){
988
errno_raising = errno;
989
perror_plus("Failed to raise privileges in order to"
990
" kill helper program");
992
if(kill(pid, SIGTERM) == -1){
995
if((errno_raising == 0) and (errno = lower_privileges()) != 0){
996
perror_plus("Failed to lower privileges after killing"
1001
} while(pret == -1 and errno == EINTR);
1003
perror_plus("waitpid");
1006
if(WIFEXITED(status)){
1007
if(WEXITSTATUS(status) != 0){
1008
fprintf_plus(stderr, "Error: iprouteadddel exited"
1009
" with status %d\n", WEXITSTATUS(status));
1014
if(WIFSIGNALED(status)){
1015
fprintf_plus(stderr, "Error: iprouteadddel died by"
1016
" signal %d\n", WTERMSIG(status));
1019
fprintf_plus(stderr, "Error: iprouteadddel crashed\n");
1023
__attribute__((nonnull, warn_unused_result))
1024
static bool add_local_route(const char *address,
1025
AvahiIfIndex if_index){
1027
fprintf_plus(stderr, "Adding route to %s\n", address);
1029
return add_delete_local_route(true, address, if_index);
1032
__attribute__((nonnull, warn_unused_result))
1033
static bool delete_local_route(const char *address,
1034
AvahiIfIndex if_index){
1036
fprintf_plus(stderr, "Removing route to %s\n", address);
1038
return add_delete_local_route(false, address, if_index);
538
1041
/* Called when a Mandos server is found */
539
static int start_mandos_communication(const char *ip, uint16_t port,
1042
__attribute__((nonnull, warn_unused_result))
1043
static int start_mandos_communication(const char *ip, in_port_t port,
540
1044
AvahiIfIndex if_index,
1045
int af, mandos_context *mc){
542
1046
int ret, tcp_sd = -1;
545
struct sockaddr_in in;
546
struct sockaddr_in6 in6;
1048
struct sockaddr_storage to;
548
1049
char *buffer = NULL;
549
1050
char *decrypted_buffer = NULL;
550
1051
size_t buffer_length = 0;
569
fprintf(stderr, "Bad address family: %d\n", af);
1074
fprintf_plus(stderr, "Bad address family: %d\n", af);
573
ret = init_gnutls_session(&session);
1079
/* If the interface is specified and we have a list of interfaces */
1080
if(if_index != AVAHI_IF_UNSPEC and mc->interfaces != NULL){
1081
/* Check if the interface is one of the interfaces we are using */
1084
char *interface = NULL;
1085
while((interface=argz_next(mc->interfaces, mc->interfaces_size,
1087
if(if_nametoindex(interface) == (unsigned int)if_index){
1094
/* This interface does not match any in the list, so we don't
1095
connect to the server */
1097
char interface[IF_NAMESIZE];
1098
if(if_indextoname((unsigned int)if_index, interface) == NULL){
1099
perror_plus("if_indextoname");
1101
fprintf_plus(stderr, "Skipping server on non-used interface"
1103
if_indextoname((unsigned int)if_index,
1111
ret = init_gnutls_session(&session, mc);
579
fprintf(stderr, "Setting up a TCP connection to %s, port %" PRIu16
1117
fprintf_plus(stderr, "Setting up a TCP connection to %s, port %"
1118
PRIuMAX "\n", ip, (uintmax_t)port);
583
tcp_sd = socket(pf, SOCK_STREAM, 0);
1121
tcp_sd = socket(pf, SOCK_STREAM | SOCK_CLOEXEC, 0);
1124
perror_plus("socket");
586
1126
goto mandos_end;
590
1131
goto mandos_end;
593
memset(&to, 0, sizeof(to));
594
1134
if(af == AF_INET6){
595
to.in6.sin6_family = (sa_family_t)af;
596
ret = inet_pton(af, ip, &to.in6.sin6_addr);
1135
struct sockaddr_in6 *to6 = (struct sockaddr_in6 *)&to;
1136
*to6 = (struct sockaddr_in6){ .sin6_family = (sa_family_t)af };
1137
ret = inet_pton(af, ip, &to6->sin6_addr);
597
1138
} else { /* IPv4 */
598
to.in.sin_family = (sa_family_t)af;
599
ret = inet_pton(af, ip, &to.in.sin_addr);
1139
struct sockaddr_in *to4 = (struct sockaddr_in *)&to;
1140
*to4 = (struct sockaddr_in){ .sin_family = (sa_family_t)af };
1141
ret = inet_pton(af, ip, &to4->sin_addr);
1145
perror_plus("inet_pton");
603
1147
goto mandos_end;
606
fprintf(stderr, "Bad address: %s\n", ip);
1151
fprintf_plus(stderr, "Bad address: %s\n", ip);
607
1153
goto mandos_end;
609
1155
if(af == AF_INET6){
610
to.in6.sin6_port = htons(port); /* Spurious warnings from
612
-Wunreachable-code */
614
if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */
615
(&to.in6.sin6_addr)){ /* -Wstrict-aliasing=2 or lower and
1156
((struct sockaddr_in6 *)&to)->sin6_port = htons(port);
1157
if(IN6_IS_ADDR_LINKLOCAL
1158
(&((struct sockaddr_in6 *)&to)->sin6_addr)){
617
1159
if(if_index == AVAHI_IF_UNSPEC){
618
fprintf(stderr, "An IPv6 link-local address is incomplete"
619
" without a network interface\n");
1160
fprintf_plus(stderr, "An IPv6 link-local address is"
1161
" incomplete without a network interface\n");
620
1163
goto mandos_end;
622
1165
/* Set the network interface number as scope */
623
to.in6.sin6_scope_id = (uint32_t)if_index;
1166
((struct sockaddr_in6 *)&to)->sin6_scope_id = (uint32_t)if_index;
626
to.in.sin_port = htons(port); /* Spurious warnings from
628
-Wunreachable-code */
1169
((struct sockaddr_in *)&to)->sin_port = htons(port);
632
1174
goto mandos_end;
636
1178
if(af == AF_INET6 and if_index != AVAHI_IF_UNSPEC){
637
1179
char interface[IF_NAMESIZE];
638
1180
if(if_indextoname((unsigned int)if_index, interface) == NULL){
639
perror("if_indextoname");
1181
perror_plus("if_indextoname");
641
fprintf(stderr, "Connection to: %s%%%s, port %" PRIu16 "\n",
642
ip, interface, port);
1183
fprintf_plus(stderr, "Connection to: %s%%%s, port %" PRIuMAX
1184
"\n", ip, interface, (uintmax_t)port);
645
fprintf(stderr, "Connection to: %s, port %" PRIu16 "\n", ip,
1187
fprintf_plus(stderr, "Connection to: %s, port %" PRIuMAX "\n",
1188
ip, (uintmax_t)port);
648
1190
char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?
649
1191
INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";
652
pcret = inet_ntop(af, &(to.in6.sin6_addr), addrstr,
655
pcret = inet_ntop(af, &(to.in.sin_addr), addrstr,
661
if(strcmp(addrstr, ip) != 0){
662
fprintf(stderr, "Canonical address form: %s\n", addrstr);
672
ret = connect(tcp_sd, &to.in6, sizeof(to));
674
ret = connect(tcp_sd, &to.in, sizeof(to)); /* IPv4 */
1193
ret = getnameinfo((struct sockaddr *)&to,
1194
sizeof(struct sockaddr_in6),
1195
addrstr, sizeof(addrstr), NULL, 0,
1198
ret = getnameinfo((struct sockaddr *)&to,
1199
sizeof(struct sockaddr_in),
1200
addrstr, sizeof(addrstr), NULL, 0,
1203
if(ret == EAI_SYSTEM){
1204
perror_plus("getnameinfo");
1205
} else if(ret != 0) {
1206
fprintf_plus(stderr, "getnameinfo: %s", gai_strerror(ret));
1207
} else if(strcmp(addrstr, ip) != 0){
1208
fprintf_plus(stderr, "Canonical address form: %s\n", addrstr);
1219
ret = connect(tcp_sd, (struct sockaddr *)&to,
1220
sizeof(struct sockaddr_in6));
1222
ret = connect(tcp_sd, (struct sockaddr *)&to, /* IPv4 */
1223
sizeof(struct sockaddr_in));
1226
if(((errno == ENETUNREACH) or (errno == EHOSTUNREACH))
1227
and if_index != AVAHI_IF_UNSPEC
1228
and connect_to == NULL
1229
and not route_added and
1230
((af == AF_INET6 and not
1231
IN6_IS_ADDR_LINKLOCAL(&(((struct sockaddr_in6 *)
1233
or (af == AF_INET and
1234
/* Not a a IPv4LL address */
1235
(ntohl(((struct sockaddr_in *)&to)->sin_addr.s_addr)
1236
& 0xFFFF0000L) != 0xA9FE0000L))){
1237
/* Work around Avahi bug - Avahi does not announce link-local
1238
addresses if it has a global address, so local hosts with
1239
*only* a link-local address (e.g. Mandos clients) cannot
1240
connect to a Mandos server announced by Avahi on a server
1241
host with a global address. Work around this by retrying
1242
with an explicit route added with the server's address.
1244
Avahi bug reference:
1245
http://lists.freedesktop.org/archives/avahi/2010-February/001833.html
1246
https://bugs.debian.org/587961
1249
fprintf_plus(stderr, "Mandos server unreachable, trying"
1253
route_added = add_local_route(ip, if_index);
1259
if(errno != ECONNREFUSED or debug){
1261
perror_plus("connect");
685
1274
const char *out = mandos_protocol_version;
971
1619
signal_received = sig;
972
1620
int old_errno = errno;
973
if(mc.simple_poll != NULL){
974
avahi_simple_poll_quit(mc.simple_poll);
1621
/* set main loop to exit */
1622
if(simple_poll != NULL){
1623
avahi_simple_poll_quit(simple_poll);
976
1625
errno = old_errno;
1628
__attribute__((nonnull, warn_unused_result))
1629
bool get_flags(const char *ifname, struct ifreq *ifr){
1633
int s = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1636
perror_plus("socket");
1640
strncpy(ifr->ifr_name, ifname, IF_NAMESIZE);
1641
ifr->ifr_name[IF_NAMESIZE-1] = '\0'; /* NUL terminate */
1642
ret = ioctl(s, SIOCGIFFLAGS, ifr);
1646
perror_plus("ioctl SIOCGIFFLAGS");
1654
__attribute__((nonnull, warn_unused_result))
1655
bool good_flags(const char *ifname, const struct ifreq *ifr){
1657
/* Reject the loopback device */
1658
if(ifr->ifr_flags & IFF_LOOPBACK){
1660
fprintf_plus(stderr, "Rejecting loopback interface \"%s\"\n",
1665
/* Accept point-to-point devices only if connect_to is specified */
1666
if(connect_to != NULL and (ifr->ifr_flags & IFF_POINTOPOINT)){
1668
fprintf_plus(stderr, "Accepting point-to-point interface"
1669
" \"%s\"\n", ifname);
1673
/* Otherwise, reject non-broadcast-capable devices */
1674
if(not (ifr->ifr_flags & IFF_BROADCAST)){
1676
fprintf_plus(stderr, "Rejecting non-broadcast interface"
1677
" \"%s\"\n", ifname);
1681
/* Reject non-ARP interfaces (including dummy interfaces) */
1682
if(ifr->ifr_flags & IFF_NOARP){
1684
fprintf_plus(stderr, "Rejecting non-ARP interface \"%s\"\n",
1690
/* Accept this device */
1692
fprintf_plus(stderr, "Interface \"%s\" is good\n", ifname);
980
1698
* This function determines if a directory entry in /sys/class/net
981
1699
* corresponds to an acceptable network device.
982
1700
* (This function is passed to scandir(3) as a filter function.)
1702
__attribute__((nonnull, warn_unused_result))
984
1703
int good_interface(const struct dirent *if_entry){
986
char *flagname = NULL;
987
int ret = asprintf(&flagname, "%s/%s/flags", sys_class_net,
993
1704
if(if_entry->d_name[0] == '.'){
996
int flags_fd = (int)TEMP_FAILURE_RETRY(open(flagname, O_RDONLY));
1001
typedef short ifreq_flags; /* ifreq.ifr_flags in netdevice(7) */
1002
/* read line from flags_fd */
1003
ssize_t to_read = (sizeof(ifreq_flags)*2)+3; /* "0x1003\n" */
1004
char *flagstring = malloc((size_t)to_read);
1005
if(flagstring == NULL){
1011
ssret = (ssize_t)TEMP_FAILURE_RETRY(read(flags_fd, flagstring,
1709
if(not get_flags(if_entry->d_name, &ifr)){
1711
fprintf_plus(stderr, "Failed to get flags for interface "
1712
"\"%s\"\n", if_entry->d_name);
1717
if(not good_flags(if_entry->d_name, &ifr)){
1724
* This function determines if a network interface is up.
1726
__attribute__((nonnull, warn_unused_result))
1727
bool interface_is_up(const char *interface){
1729
if(not get_flags(interface, &ifr)){
1731
fprintf_plus(stderr, "Failed to get flags for interface "
1732
"\"%s\"\n", interface);
1737
return (bool)(ifr.ifr_flags & IFF_UP);
1741
* This function determines if a network interface is running
1743
__attribute__((nonnull, warn_unused_result))
1744
bool interface_is_running(const char *interface){
1746
if(not get_flags(interface, &ifr)){
1748
fprintf_plus(stderr, "Failed to get flags for interface "
1749
"\"%s\"\n", interface);
1754
return (bool)(ifr.ifr_flags & IFF_RUNNING);
1757
__attribute__((nonnull, pure, warn_unused_result))
1758
int notdotentries(const struct dirent *direntry){
1759
/* Skip "." and ".." */
1760
if(direntry->d_name[0] == '.'
1761
and (direntry->d_name[1] == '\0'
1762
or (direntry->d_name[1] == '.'
1763
and direntry->d_name[2] == '\0'))){
1769
/* Is this directory entry a runnable program? */
1770
__attribute__((nonnull, warn_unused_result))
1771
int runnable_hook(const struct dirent *direntry){
1776
if((direntry->d_name)[0] == '\0'){
1781
sret = strspn(direntry->d_name, "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
1782
"abcdefghijklmnopqrstuvwxyz"
1785
if((direntry->d_name)[sret] != '\0'){
1786
/* Contains non-allowed characters */
1788
fprintf_plus(stderr, "Ignoring hook \"%s\" with bad name\n",
1794
ret = fstatat(hookdir_fd, direntry->d_name, &st, 0);
1797
perror_plus("Could not stat hook");
1801
if(not (S_ISREG(st.st_mode))){
1802
/* Not a regular file */
1804
fprintf_plus(stderr, "Ignoring hook \"%s\" - not a file\n",
1809
if(not (st.st_mode & (S_IXUSR | S_IXGRP | S_IXOTH))){
1810
/* Not executable */
1812
fprintf_plus(stderr, "Ignoring hook \"%s\" - not executable\n",
1818
fprintf_plus(stderr, "Hook \"%s\" is acceptable\n",
1824
__attribute__((nonnull, warn_unused_result))
1825
int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,
1826
mandos_context *mc){
1828
struct timespec now;
1829
struct timespec waited_time;
1830
intmax_t block_time;
1833
if(mc->current_server == NULL){
1835
fprintf_plus(stderr, "Wait until first server is found."
1838
ret = avahi_simple_poll_iterate(s, -1);
1841
fprintf_plus(stderr, "Check current_server if we should run"
1844
/* the current time */
1845
ret = clock_gettime(CLOCK_MONOTONIC, &now);
1847
perror_plus("clock_gettime");
1850
/* Calculating in ms how long time between now and server
1851
who we visted longest time ago. Now - last seen. */
1852
waited_time.tv_sec = (now.tv_sec
1853
- mc->current_server->last_seen.tv_sec);
1854
waited_time.tv_nsec = (now.tv_nsec
1855
- mc->current_server->last_seen.tv_nsec);
1856
/* total time is 10s/10,000ms.
1857
Converting to s from ms by dividing by 1,000,
1858
and ns to ms by dividing by 1,000,000. */
1859
block_time = ((retry_interval
1860
- ((intmax_t)waited_time.tv_sec * 1000))
1861
- ((intmax_t)waited_time.tv_nsec / 1000000));
1864
fprintf_plus(stderr, "Blocking for %" PRIdMAX " ms\n",
1868
if(block_time <= 0){
1869
ret = start_mandos_communication(mc->current_server->ip,
1870
mc->current_server->port,
1871
mc->current_server->if_index,
1872
mc->current_server->af, mc);
1874
avahi_simple_poll_quit(s);
1877
ret = clock_gettime(CLOCK_MONOTONIC,
1878
&mc->current_server->last_seen);
1880
perror_plus("clock_gettime");
1883
mc->current_server = mc->current_server->next;
1884
block_time = 0; /* Call avahi to find new Mandos
1885
servers, but don't block */
1888
ret = avahi_simple_poll_iterate(s, (int)block_time);
1891
if(ret > 0 or errno != EINTR){
1892
return (ret != 1) ? ret : 0;
1898
__attribute__((nonnull))
1899
void run_network_hooks(const char *mode, const char *interface,
1901
struct dirent **direntries = NULL;
1902
if(hookdir_fd == -1){
1903
hookdir_fd = open(hookdir, O_RDONLY | O_DIRECTORY | O_PATH
1905
if(hookdir_fd == -1){
1906
if(errno == ENOENT){
1908
fprintf_plus(stderr, "Network hook directory \"%s\" not"
1909
" found\n", hookdir);
1912
perror_plus("open");
1918
#if __GLIBC_PREREQ(2, 15)
1919
int numhooks = scandirat(hookdir_fd, ".", &direntries,
1920
runnable_hook, alphasort);
1921
#else /* not __GLIBC_PREREQ(2, 15) */
1922
int numhooks = scandir(hookdir, &direntries, runnable_hook,
1924
#endif /* not __GLIBC_PREREQ(2, 15) */
1925
#else /* not __GLIBC__ */
1926
int numhooks = scandir(hookdir, &direntries, runnable_hook,
1928
#endif /* not __GLIBC__ */
1930
perror_plus("scandir");
1933
struct dirent *direntry;
1935
int devnull = (int)TEMP_FAILURE_RETRY(open("/dev/null", O_RDONLY));
1937
perror_plus("open(\"/dev/null\", O_RDONLY)");
1940
for(int i = 0; i < numhooks; i++){
1941
direntry = direntries[i];
1943
fprintf_plus(stderr, "Running network hook \"%s\"\n",
1946
pid_t hook_pid = fork();
1949
/* Raise privileges */
1950
errno = raise_privileges_permanently();
1952
perror_plus("Failed to raise privileges");
1959
perror_plus("setgid");
1962
/* Reset supplementary groups */
1964
ret = setgroups(0, NULL);
1966
perror_plus("setgroups");
1969
ret = setenv("MANDOSNETHOOKDIR", hookdir, 1);
1971
perror_plus("setenv");
1974
ret = setenv("DEVICE", interface, 1);
1976
perror_plus("setenv");
1979
ret = setenv("VERBOSITY", debug ? "1" : "0", 1);
1981
perror_plus("setenv");
1984
ret = setenv("MODE", mode, 1);
1986
perror_plus("setenv");
1990
ret = asprintf(&delaystring, "%f", (double)delay);
1992
perror_plus("asprintf");
1995
ret = setenv("DELAY", delaystring, 1);
1998
perror_plus("setenv");
2002
if(connect_to != NULL){
2003
ret = setenv("CONNECT", connect_to, 1);
2005
perror_plus("setenv");
2009
int hook_fd = (int)TEMP_FAILURE_RETRY(openat(hookdir_fd,
2013
perror_plus("openat");
2014
_exit(EXIT_FAILURE);
2016
if(close(hookdir_fd) == -1){
2017
perror_plus("close");
2018
_exit(EXIT_FAILURE);
2020
ret = dup2(devnull, STDIN_FILENO);
2022
perror_plus("dup2(devnull, STDIN_FILENO)");
2025
ret = close(devnull);
2027
perror_plus("close");
2030
ret = dup2(STDERR_FILENO, STDOUT_FILENO);
2032
perror_plus("dup2(STDERR_FILENO, STDOUT_FILENO)");
2035
if(fexecve(hook_fd, (char *const []){ direntry->d_name, NULL },
2037
perror_plus("fexecve");
2038
_exit(EXIT_FAILURE);
2042
perror_plus("fork");
2047
if(TEMP_FAILURE_RETRY(waitpid(hook_pid, &status, 0)) == -1){
2048
perror_plus("waitpid");
2052
if(WIFEXITED(status)){
2053
if(WEXITSTATUS(status) != 0){
2054
fprintf_plus(stderr, "Warning: network hook \"%s\" exited"
2055
" with status %d\n", direntry->d_name,
2056
WEXITSTATUS(status));
2060
} else if(WIFSIGNALED(status)){
2061
fprintf_plus(stderr, "Warning: network hook \"%s\" died by"
2062
" signal %d\n", direntry->d_name,
2067
fprintf_plus(stderr, "Warning: network hook \"%s\""
2068
" crashed\n", direntry->d_name);
2074
fprintf_plus(stderr, "Network hook \"%s\" ran successfully\n",
2080
if(close(hookdir_fd) == -1){
2081
perror_plus("close");
2088
__attribute__((nonnull, warn_unused_result))
2089
error_t bring_up_interface(const char *const interface,
2091
error_t old_errno = errno;
2093
struct ifreq network;
2094
unsigned int if_index = if_nametoindex(interface);
2096
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
2106
if(not interface_is_up(interface)){
2107
error_t ret_errno = 0, ioctl_errno = 0;
2108
if(not get_flags(interface, &network)){
2110
fprintf_plus(stderr, "Failed to get flags for interface "
2111
"\"%s\"\n", interface);
2115
network.ifr_flags |= IFF_UP; /* set flag */
2117
int sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
2120
perror_plus("socket");
2128
perror_plus("close");
2135
fprintf_plus(stderr, "Bringing up interface \"%s\"\n",
2139
/* Raise privileges */
2140
ret_errno = raise_privileges();
2143
perror_plus("Failed to raise privileges");
2148
bool restore_loglevel = false;
2150
/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO
2151
messages about the network interface to mess up the prompt */
2152
ret_linux = klogctl(8, NULL, 5);
2153
if(ret_linux == -1){
2154
perror_plus("klogctl");
2156
restore_loglevel = true;
2159
#endif /* __linux__ */
2160
int ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
2161
ioctl_errno = errno;
2163
if(restore_loglevel){
2164
ret_linux = klogctl(7, NULL, 0);
2165
if(ret_linux == -1){
2166
perror_plus("klogctl");
2169
#endif /* __linux__ */
2171
/* If raise_privileges() succeeded above */
2173
/* Lower privileges */
2174
ret_errno = lower_privileges();
2177
perror_plus("Failed to lower privileges");
2181
/* Close the socket */
2184
perror_plus("close");
2187
if(ret_setflags == -1){
2188
errno = ioctl_errno;
2189
perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");
2194
fprintf_plus(stderr, "Interface \"%s\" is already up; good\n",
2198
/* Sleep checking until interface is running.
2199
Check every 0.25s, up to total time of delay */
2200
for(int i=0; i < delay * 4; i++){
2201
if(interface_is_running(interface)){
1028
tmpmax = strtoimax(flagstring, &tmp, 0);
1029
if(errno != 0 or tmp == flagstring or (*tmp != '\0'
1030
and not (isspace(*tmp)))
1031
or tmpmax != (ifreq_flags)tmpmax){
1036
ifreq_flags flags = (ifreq_flags)tmpmax;
1037
/* Reject the loopback device */
1038
if(flags & IFF_LOOPBACK){
1041
/* Accept point-to-point devices only if connect_to is specified */
1042
if(connect_to != NULL and (flags & IFF_POINTOPOINT)){
1045
/* Otherwise, reject non-broadcast-capable devices */
1046
if(not (flags & IFF_BROADCAST)){
1049
/* Accept this device */
2204
struct timespec sleeptime = { .tv_nsec = 250000000 };
2205
ret = nanosleep(&sleeptime, NULL);
2206
if(ret == -1 and errno != EINTR){
2207
perror_plus("nanosleep");
2215
__attribute__((nonnull, warn_unused_result))
2216
error_t take_down_interface(const char *const interface){
2217
error_t old_errno = errno;
2218
struct ifreq network;
2219
unsigned int if_index = if_nametoindex(interface);
2221
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
2225
if(interface_is_up(interface)){
2226
error_t ret_errno = 0, ioctl_errno = 0;
2227
if(not get_flags(interface, &network) and debug){
2229
fprintf_plus(stderr, "Failed to get flags for interface "
2230
"\"%s\"\n", interface);
2234
network.ifr_flags &= ~(short)IFF_UP; /* clear flag */
2236
int sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
2239
perror_plus("socket");
2245
fprintf_plus(stderr, "Taking down interface \"%s\"\n",
2249
/* Raise privileges */
2250
ret_errno = raise_privileges();
2253
perror_plus("Failed to raise privileges");
2256
int ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
2257
ioctl_errno = errno;
2259
/* If raise_privileges() succeeded above */
2261
/* Lower privileges */
2262
ret_errno = lower_privileges();
2265
perror_plus("Failed to lower privileges");
2269
/* Close the socket */
2270
int ret = close(sd);
2272
perror_plus("close");
2275
if(ret_setflags == -1){
2276
errno = ioctl_errno;
2277
perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");
2282
fprintf_plus(stderr, "Interface \"%s\" is already down; odd\n",
1053
2290
int main(int argc, char *argv[]){
2291
mandos_context mc = { .server = NULL, .dh_bits = 0,
2292
.priority = "SECURE256:!CTYPE-X.509"
2293
":+CTYPE-OPENPGP:!RSA:+SIGN-DSA-SHA256",
2294
.current_server = NULL, .interfaces = NULL,
2295
.interfaces_size = 0 };
1054
2296
AvahiSServiceBrowser *sb = NULL;
1057
2299
intmax_t tmpmax;
1059
2301
int exitcode = EXIT_SUCCESS;
1060
const char *interface = "";
1061
struct ifreq network;
1063
bool take_down_interface = false;
1066
char tempdir[] = "/tmp/mandosXXXXXX";
1067
bool tempdir_created = false;
2302
char *interfaces_to_take_down = NULL;
2303
size_t interfaces_to_take_down_size = 0;
2304
char run_tempdir[] = "/run/tmp/mandosXXXXXX";
2305
char old_tempdir[] = "/tmp/mandosXXXXXX";
2306
char *tempdir = NULL;
1068
2307
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
1069
2308
const char *seckey = PATHDIR "/" SECKEY;
1070
2309
const char *pubkey = PATHDIR "/" PUBKEY;
2310
const char *dh_params_file = NULL;
2311
char *interfaces_hooks = NULL;
1072
2313
bool gnutls_initialized = false;
1073
2314
bool gpgme_initialized = false;
1074
2315
float delay = 2.5f;
2316
double retry_interval = 10; /* 10s between trying a server and
2317
retrying the same server again */
1076
2319
struct sigaction old_sigterm_action = { .sa_handler = SIG_DFL };
1077
2320
struct sigaction sigterm_action = { .sa_handler = handle_sigterm };
1170
2442
delay = strtof(arg, &tmp);
1171
2443
if(errno != 0 or tmp == arg or *tmp != '\0'){
1172
fprintf(stderr, "Bad delay\n");
2444
argp_error(state, "Bad delay");
2446
case 132: /* --retry */
2448
retry_interval = strtod(arg, &tmp);
2449
if(errno != 0 or tmp == arg or *tmp != '\0'
2450
or (retry_interval * 1000) > INT_MAX
2451
or retry_interval < 0){
2452
argp_error(state, "Bad retry interval");
2455
case 133: /* --network-hook-dir */
2459
* These reproduce what we would get without ARGP_NO_HELP
2461
case '?': /* --help */
2462
argp_state_help(state, state->out_stream,
2463
(ARGP_HELP_STD_HELP | ARGP_HELP_EXIT_ERR)
2464
& ~(unsigned int)ARGP_HELP_EXIT_OK);
2465
case -3: /* --usage */
2466
argp_state_help(state, state->out_stream,
2467
ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);
2468
case 'V': /* --version */
2469
fprintf_plus(state->out_stream, "%s\n", argp_program_version);
2470
exit(argp_err_exit_status);
1181
2473
return ARGP_ERR_UNKNOWN;
1186
2478
struct argp argp = { .options = options, .parser = parse_opt,
1187
2479
.args_doc = "",
1188
2480
.doc = "Mandos client -- Get and decrypt"
1189
2481
" passwords from a Mandos server" };
1190
ret = argp_parse(&argp, argc, argv, 0, 0, NULL);
1191
if(ret == ARGP_ERR_UNKNOWN){
1192
fprintf(stderr, "Unknown error while parsing arguments\n");
1193
exitcode = EXIT_FAILURE;
2482
ret = argp_parse(&argp, argc, argv,
2483
ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);
2490
perror_plus("argp_parse");
2491
exitcode = EX_OSERR;
2494
exitcode = EX_USAGE;
2500
/* Work around Debian bug #633582:
2501
<http://bugs.debian.org/633582> */
2503
/* Re-raise privileges */
2504
ret_errno = raise_privileges();
2507
perror_plus("Failed to raise privileges");
2511
if(strcmp(seckey, PATHDIR "/" SECKEY) == 0){
2512
int seckey_fd = open(seckey, O_RDONLY);
2513
if(seckey_fd == -1){
2514
perror_plus("open");
2516
ret = (int)TEMP_FAILURE_RETRY(fstat(seckey_fd, &st));
2518
perror_plus("fstat");
2520
if(S_ISREG(st.st_mode)
2521
and st.st_uid == 0 and st.st_gid == 0){
2522
ret = fchown(seckey_fd, uid, gid);
2524
perror_plus("fchown");
2532
if(strcmp(pubkey, PATHDIR "/" PUBKEY) == 0){
2533
int pubkey_fd = open(pubkey, O_RDONLY);
2534
if(pubkey_fd == -1){
2535
perror_plus("open");
2537
ret = (int)TEMP_FAILURE_RETRY(fstat(pubkey_fd, &st));
2539
perror_plus("fstat");
2541
if(S_ISREG(st.st_mode)
2542
and st.st_uid == 0 and st.st_gid == 0){
2543
ret = fchown(pubkey_fd, uid, gid);
2545
perror_plus("fchown");
2553
if(dh_params_file != NULL
2554
and strcmp(dh_params_file, PATHDIR "/dhparams.pem" ) == 0){
2555
int dhparams_fd = open(dh_params_file, O_RDONLY);
2556
if(dhparams_fd == -1){
2557
perror_plus("open");
2559
ret = (int)TEMP_FAILURE_RETRY(fstat(dhparams_fd, &st));
2561
perror_plus("fstat");
2563
if(S_ISREG(st.st_mode)
2564
and st.st_uid == 0 and st.st_gid == 0){
2565
ret = fchown(dhparams_fd, uid, gid);
2567
perror_plus("fchown");
2575
/* Lower privileges */
2576
ret_errno = lower_privileges();
2579
perror_plus("Failed to lower privileges");
2584
/* Remove invalid interface names (except "none") */
2586
char *interface = NULL;
2587
while((interface = argz_next(mc.interfaces, mc.interfaces_size,
2589
if(strcmp(interface, "none") != 0
2590
and if_nametoindex(interface) == 0){
2591
if(interface[0] != '\0'){
2592
fprintf_plus(stderr, "Not using nonexisting interface"
2593
" \"%s\"\n", interface);
2595
argz_delete(&mc.interfaces, &mc.interfaces_size, interface);
2601
/* Run network hooks */
2603
if(mc.interfaces != NULL){
2604
interfaces_hooks = malloc(mc.interfaces_size);
2605
if(interfaces_hooks == NULL){
2606
perror_plus("malloc");
2609
memcpy(interfaces_hooks, mc.interfaces, mc.interfaces_size);
2610
argz_stringify(interfaces_hooks, mc.interfaces_size, (int)',');
2612
run_network_hooks("start", interfaces_hooks != NULL ?
2613
interfaces_hooks : "", delay);
1199
2617
avahi_set_log_function(empty_log);
1202
if(interface[0] == '\0'){
1203
struct dirent **direntries;
1204
ret = scandir(sys_class_net, &direntries, good_interface,
1207
/* Pick the first good interface */
1208
interface = strdup(direntries[0]->d_name);
1209
if(interface == NULL){
1212
exitcode = EXIT_FAILURE;
1218
fprintf(stderr, "Could not find a network interface\n");
1219
exitcode = EXIT_FAILURE;
1224
2620
/* Initialize Avahi early so avahi_simple_poll_quit() can be called
1225
2621
from the signal handler */
1226
2622
/* Initialize the pseudo-RNG for Avahi */
1227
2623
srand((unsigned int) time(NULL));
1228
mc.simple_poll = avahi_simple_poll_new();
1229
if(mc.simple_poll == NULL){
1230
fprintf(stderr, "Avahi: Failed to create simple poll object.\n");
1231
exitcode = EXIT_FAILURE;
2624
simple_poll = avahi_simple_poll_new();
2625
if(simple_poll == NULL){
2626
fprintf_plus(stderr,
2627
"Avahi: Failed to create simple poll object.\n");
2628
exitcode = EX_UNAVAILABLE;
1235
2632
sigemptyset(&sigterm_action.sa_mask);
1236
2633
ret = sigaddset(&sigterm_action.sa_mask, SIGINT);
1238
perror("sigaddset");
1239
exitcode = EXIT_FAILURE;
2635
perror_plus("sigaddset");
2636
exitcode = EX_OSERR;
1242
2639
ret = sigaddset(&sigterm_action.sa_mask, SIGHUP);
1244
perror("sigaddset");
1245
exitcode = EXIT_FAILURE;
2641
perror_plus("sigaddset");
2642
exitcode = EX_OSERR;
1248
2645
ret = sigaddset(&sigterm_action.sa_mask, SIGTERM);
1250
perror("sigaddset");
1251
exitcode = EXIT_FAILURE;
2647
perror_plus("sigaddset");
2648
exitcode = EX_OSERR;
1254
2651
/* Need to check if the handler is SIG_IGN before handling:
1258
2655
ret = sigaction(SIGINT, NULL, &old_sigterm_action);
1260
perror("sigaction");
1261
return EXIT_FAILURE;
2657
perror_plus("sigaction");
1263
2660
if(old_sigterm_action.sa_handler != SIG_IGN){
1264
2661
ret = sigaction(SIGINT, &sigterm_action, NULL);
1266
perror("sigaction");
1267
exitcode = EXIT_FAILURE;
2663
perror_plus("sigaction");
2664
exitcode = EX_OSERR;
1271
2668
ret = sigaction(SIGHUP, NULL, &old_sigterm_action);
1273
perror("sigaction");
1274
return EXIT_FAILURE;
2670
perror_plus("sigaction");
1276
2673
if(old_sigterm_action.sa_handler != SIG_IGN){
1277
2674
ret = sigaction(SIGHUP, &sigterm_action, NULL);
1279
perror("sigaction");
1280
exitcode = EXIT_FAILURE;
2676
perror_plus("sigaction");
2677
exitcode = EX_OSERR;
1284
2681
ret = sigaction(SIGTERM, NULL, &old_sigterm_action);
1286
perror("sigaction");
1287
return EXIT_FAILURE;
2683
perror_plus("sigaction");
1289
2686
if(old_sigterm_action.sa_handler != SIG_IGN){
1290
2687
ret = sigaction(SIGTERM, &sigterm_action, NULL);
1292
perror("sigaction");
1293
exitcode = EXIT_FAILURE;
1298
/* If the interface is down, bring it up */
1299
if(strcmp(interface, "none") != 0){
1300
if_index = (AvahiIfIndex) if_nametoindex(interface);
1302
fprintf(stderr, "No such interface: \"%s\"\n", interface);
1303
exitcode = EXIT_FAILURE;
1311
/* Re-raise priviliges */
1319
/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO
1320
messages to mess up the prompt */
1321
ret = klogctl(8, NULL, 5);
1322
bool restore_loglevel = true;
1324
restore_loglevel = false;
1327
#endif /* __linux__ */
1329
sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1332
exitcode = EXIT_FAILURE;
1334
if(restore_loglevel){
1335
ret = klogctl(7, NULL, 0);
1340
#endif /* __linux__ */
1341
/* Lower privileges */
1349
strcpy(network.ifr_name, interface);
1350
ret = ioctl(sd, SIOCGIFFLAGS, &network);
1352
perror("ioctl SIOCGIFFLAGS");
1354
if(restore_loglevel){
1355
ret = klogctl(7, NULL, 0);
1360
#endif /* __linux__ */
1361
exitcode = EXIT_FAILURE;
1362
/* Lower privileges */
1370
if((network.ifr_flags & IFF_UP) == 0){
1371
network.ifr_flags |= IFF_UP;
1372
take_down_interface = true;
1373
ret = ioctl(sd, SIOCSIFFLAGS, &network);
1375
take_down_interface = false;
1376
perror("ioctl SIOCSIFFLAGS");
1377
exitcode = EXIT_FAILURE;
1379
if(restore_loglevel){
1380
ret = klogctl(7, NULL, 0);
2689
perror_plus("sigaction");
2690
exitcode = EX_OSERR;
2695
/* If no interfaces were specified, make a list */
2696
if(mc.interfaces == NULL){
2697
struct dirent **direntries = NULL;
2698
/* Look for any good interfaces */
2699
ret = scandir(sys_class_net, &direntries, good_interface,
2702
/* Add all found interfaces to interfaces list */
2703
for(int i = 0; i < ret; ++i){
2704
ret_errno = argz_add(&mc.interfaces, &mc.interfaces_size,
2705
direntries[i]->d_name);
2708
perror_plus("argz_add");
2709
free(direntries[i]);
2713
fprintf_plus(stderr, "Will use interface \"%s\"\n",
2714
direntries[i]->d_name);
2716
free(direntries[i]);
2723
fprintf_plus(stderr, "Could not find a network interface\n");
2724
exitcode = EXIT_FAILURE;
2729
/* Bring up interfaces which are down, and remove any "none"s */
2731
char *interface = NULL;
2732
while((interface = argz_next(mc.interfaces, mc.interfaces_size,
2734
/* If interface name is "none", stop bringing up interfaces.
2735
Also remove all instances of "none" from the list */
2736
if(strcmp(interface, "none") == 0){
2737
argz_delete(&mc.interfaces, &mc.interfaces_size,
2740
while((interface = argz_next(mc.interfaces,
2741
mc.interfaces_size, interface))){
2742
if(strcmp(interface, "none") == 0){
2743
argz_delete(&mc.interfaces, &mc.interfaces_size,
1385
#endif /* __linux__ */
1386
/* Lower privileges */
1395
/* sleep checking until interface is running */
1396
for(int i=0; i < delay * 4; i++){
1397
ret = ioctl(sd, SIOCGIFFLAGS, &network);
1399
perror("ioctl SIOCGIFFLAGS");
1400
} else if(network.ifr_flags & IFF_RUNNING){
1403
struct timespec sleeptime = { .tv_nsec = 250000000 };
1404
ret = nanosleep(&sleeptime, NULL);
1405
if(ret == -1 and errno != EINTR){
1406
perror("nanosleep");
1409
if(not take_down_interface){
1410
/* We won't need the socket anymore */
1411
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1417
if(restore_loglevel){
1418
/* Restores kernel loglevel to default */
1419
ret = klogctl(7, NULL, 0);
1424
#endif /* __linux__ */
1425
/* Lower privileges */
1427
if(take_down_interface){
1428
/* Lower privileges */
1434
/* Lower privileges permanently */
2750
bool interface_was_up = interface_is_up(interface);
2751
errno = bring_up_interface(interface, delay);
2752
if(not interface_was_up){
2754
fprintf_plus(stderr, "Failed to bring up interface \"%s\":"
2755
" %s\n", interface, strerror(errno));
2757
errno = argz_add(&interfaces_to_take_down,
2758
&interfaces_to_take_down_size,
2761
perror_plus("argz_add");
2766
if(debug and (interfaces_to_take_down == NULL)){
2767
fprintf_plus(stderr, "No interfaces were brought up\n");
2771
/* If we only got one interface, explicitly use only that one */
2772
if(argz_count(mc.interfaces, mc.interfaces_size) == 1){
2774
fprintf_plus(stderr, "Using only interface \"%s\"\n",
2777
if_index = (AvahiIfIndex)if_nametoindex(mc.interfaces);
1446
ret = init_gnutls_global(pubkey, seckey);
2784
ret = init_gnutls_global(pubkey, seckey, dh_params_file, &mc);
1448
fprintf(stderr, "init_gnutls_global failed\n");
1449
exitcode = EXIT_FAILURE;
2786
fprintf_plus(stderr, "init_gnutls_global failed\n");
2787
exitcode = EX_UNAVAILABLE;
1452
2790
gnutls_initialized = true;
1614
2984
gpgme_release(mc.ctx);
1617
/* Take down the network interface */
1618
if(take_down_interface){
1619
/* Re-raise priviliges */
1626
ret = ioctl(sd, SIOCGIFFLAGS, &network);
1628
perror("ioctl SIOCGIFFLAGS");
1629
} else if(network.ifr_flags & IFF_UP) {
1630
network.ifr_flags &= ~IFF_UP; /* clear flag */
1631
ret = ioctl(sd, SIOCSIFFLAGS, &network);
1633
perror("ioctl SIOCSIFFLAGS");
1636
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1640
/* Lower privileges permanently */
1649
/* Removes the temp directory used by GPGME */
1650
if(tempdir_created){
1652
struct dirent *direntry;
1653
d = opendir(tempdir);
1655
if(errno != ENOENT){
1660
direntry = readdir(d);
1661
if(direntry == NULL){
1664
/* Skip "." and ".." */
1665
if(direntry->d_name[0] == '.'
1666
and (direntry->d_name[1] == '\0'
1667
or (direntry->d_name[1] == '.'
1668
and direntry->d_name[2] == '\0'))){
1671
char *fullname = NULL;
1672
ret = asprintf(&fullname, "%s/%s", tempdir,
1678
ret = remove(fullname);
1680
fprintf(stderr, "remove(\"%s\"): %s\n", fullname,
1687
ret = rmdir(tempdir);
1688
if(ret == -1 and errno != ENOENT){
2987
/* Cleans up the circular linked list of Mandos servers the client
2989
if(mc.current_server != NULL){
2990
mc.current_server->prev->next = NULL;
2991
while(mc.current_server != NULL){
2992
server *next = mc.current_server->next;
2994
#pragma GCC diagnostic push
2995
#pragma GCC diagnostic ignored "-Wcast-qual"
2997
free((char *)(mc.current_server->ip));
2999
#pragma GCC diagnostic pop
3001
free(mc.current_server);
3002
mc.current_server = next;
3006
/* Re-raise privileges */
3008
ret_errno = raise_privileges();
3011
perror_plus("Failed to raise privileges");
3014
/* Run network hooks */
3015
run_network_hooks("stop", interfaces_hooks != NULL ?
3016
interfaces_hooks : "", delay);
3018
/* Take down the network interfaces which were brought up */
3020
char *interface = NULL;
3021
while((interface=argz_next(interfaces_to_take_down,
3022
interfaces_to_take_down_size,
3024
ret_errno = take_down_interface(interface);
3027
perror_plus("Failed to take down interface");
3030
if(debug and (interfaces_to_take_down == NULL)){
3031
fprintf_plus(stderr, "No interfaces needed to be taken"
3037
ret_errno = lower_privileges_permanently();
3040
perror_plus("Failed to lower privileges permanently");
3044
free(interfaces_to_take_down);
3045
free(interfaces_hooks);
3047
/* Removes the GPGME temp directory and all files inside */
3048
if(tempdir != NULL){
3049
struct dirent **direntries = NULL;
3050
int tempdir_fd = (int)TEMP_FAILURE_RETRY(open(tempdir, O_RDONLY
3054
if(tempdir_fd == -1){
3055
perror_plus("open");
3058
#if __GLIBC_PREREQ(2, 15)
3059
int numentries = scandirat(tempdir_fd, ".", &direntries,
3060
notdotentries, alphasort);
3061
#else /* not __GLIBC_PREREQ(2, 15) */
3062
int numentries = scandir(tempdir, &direntries, notdotentries,
3064
#endif /* not __GLIBC_PREREQ(2, 15) */
3065
#else /* not __GLIBC__ */
3066
int numentries = scandir(tempdir, &direntries, notdotentries,
3068
#endif /* not __GLIBC__ */
3069
if(numentries >= 0){
3070
for(int i = 0; i < numentries; i++){
3071
ret = unlinkat(tempdir_fd, direntries[i]->d_name, 0);
3073
fprintf_plus(stderr, "unlinkat(open(\"%s\", O_RDONLY),"
3074
" \"%s\", 0): %s\n", tempdir,
3075
direntries[i]->d_name, strerror(errno));
3077
free(direntries[i]);
3080
/* need to clean even if 0 because man page doesn't specify */
3082
if(numentries == -1){
3083
perror_plus("scandir");
3085
ret = rmdir(tempdir);
3086
if(ret == -1 and errno != ENOENT){
3087
perror_plus("rmdir");