9
9
* "browse_callback", and parts of "main".
11
11
* Everything else is
12
* Copyright © 2008,2009 Teddy Hogeborn
13
* Copyright © 2008,2009 Björn Påhlsson
15
* This program is free software: you can redistribute it and/or
16
* modify it under the terms of the GNU General Public License as
17
* published by the Free Software Foundation, either version 3 of the
18
* License, or (at your option) any later version.
20
* This program is distributed in the hope that it will be useful, but
12
* Copyright © 2008-2018 Teddy Hogeborn
13
* Copyright © 2008-2018 Björn Påhlsson
15
* This file is part of Mandos.
17
* Mandos is free software: you can redistribute it and/or modify it
18
* under the terms of the GNU General Public License as published by
19
* the Free Software Foundation, either version 3 of the License, or
20
* (at your option) any later version.
22
* Mandos is distributed in the hope that it will be useful, but
21
23
* WITHOUT ANY WARRANTY; without even the implied warranty of
22
24
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
23
25
* General Public License for more details.
25
27
* You should have received a copy of the GNU General Public License
26
* along with this program. If not, see
27
* <http://www.gnu.org/licenses/>.
28
* along with Mandos. If not, see <http://www.gnu.org/licenses/>.
29
* Contact the authors at <mandos@fukt.bsnet.se>.
30
* Contact the authors at <mandos@recompile.se>.
32
33
/* Needed by GPGME, specifically gpgme_data_seek() */
34
#ifndef _LARGEFILE_SOURCE
33
35
#define _LARGEFILE_SOURCE
36
#endif /* not _LARGEFILE_SOURCE */
37
#ifndef _FILE_OFFSET_BITS
34
38
#define _FILE_OFFSET_BITS 64
39
#endif /* not _FILE_OFFSET_BITS */
36
41
#define _GNU_SOURCE /* TEMP_FAILURE_RETRY(), asprintf() */
38
43
#include <stdio.h> /* fprintf(), stderr, fwrite(),
39
stdout, ferror(), sscanf(),
41
#include <stdint.h> /* uint16_t, uint32_t */
45
#include <stdint.h> /* uint16_t, uint32_t, intptr_t */
42
46
#include <stddef.h> /* NULL, size_t, ssize_t */
43
#include <stdlib.h> /* free(), EXIT_SUCCESS, EXIT_FAILURE,
45
#include <stdbool.h> /* bool, true */
46
#include <string.h> /* memset(), strcmp(), strlen(),
47
strerror(), asprintf(), strcpy() */
48
#include <sys/ioctl.h> /* ioctl */
47
#include <stdlib.h> /* free(), EXIT_SUCCESS, srand(),
49
#include <stdbool.h> /* bool, false, true */
50
#include <string.h> /* strcmp(), strlen(), strerror(),
51
asprintf(), strncpy(), strsignal()
53
#include <sys/ioctl.h> /* ioctl */
49
54
#include <sys/types.h> /* socket(), inet_pton(), sockaddr,
50
55
sockaddr_in6, PF_INET6,
51
SOCK_STREAM, INET6_ADDRSTRLEN,
52
uid_t, gid_t, open(), opendir(),
54
#include <sys/stat.h> /* open() */
56
SOCK_STREAM, uid_t, gid_t, open(),
58
#include <sys/stat.h> /* open(), S_ISREG */
55
59
#include <sys/socket.h> /* socket(), struct sockaddr_in6,
56
struct in6_addr, inet_pton(),
58
#include <fcntl.h> /* open() */
60
inet_pton(), connect(),
62
#include <fcntl.h> /* open(), unlinkat(), AT_REMOVEDIR */
59
63
#include <dirent.h> /* opendir(), struct dirent, readdir()
61
#include <inttypes.h> /* PRIu16, intmax_t, SCNdMAX */
62
#include <assert.h> /* assert() */
63
#include <errno.h> /* perror(), errno */
64
#include <time.h> /* nanosleep(), time() */
65
#include <inttypes.h> /* PRIu16, PRIdMAX, intmax_t,
67
#include <errno.h> /* perror(), errno, EINTR, EINVAL,
68
EAI_SYSTEM, ENETUNREACH,
69
EHOSTUNREACH, ECONNREFUSED, EPROTO,
70
EIO, ENOENT, ENXIO, ENOMEM, EISDIR,
72
program_invocation_short_name */
73
#include <time.h> /* nanosleep(), time(), sleep() */
65
74
#include <net/if.h> /* ioctl, ifreq, SIOCGIFFLAGS, IFF_UP,
66
75
SIOCSIFFLAGS, if_indextoname(),
67
76
if_nametoindex(), IF_NAMESIZE */
68
#include <netinet/in.h>
77
#include <netinet/in.h> /* IN6_IS_ADDR_LINKLOCAL,
78
INET_ADDRSTRLEN, INET6_ADDRSTRLEN
69
80
#include <unistd.h> /* close(), SEEK_SET, off_t, write(),
70
getuid(), getgid(), setuid(),
72
#include <arpa/inet.h> /* inet_pton(), htons */
73
#include <iso646.h> /* not, and, or */
81
getuid(), getgid(), seteuid(),
82
setgid(), pause(), _exit(),
84
#include <arpa/inet.h> /* inet_pton(), htons() */
85
#include <iso646.h> /* not, or, and */
74
86
#include <argp.h> /* struct argp_option, error_t, struct
75
87
argp_state, struct argp,
76
88
argp_parse(), ARGP_KEY_ARG,
77
89
ARGP_KEY_END, ARGP_ERR_UNKNOWN */
90
#include <signal.h> /* sigemptyset(), sigaddset(),
91
sigaction(), SIGTERM, sig_atomic_t,
93
#include <sysexits.h> /* EX_OSERR, EX_USAGE, EX_UNAVAILABLE,
94
EX_NOHOST, EX_IOERR, EX_PROTOCOL */
95
#include <sys/wait.h> /* waitpid(), WIFEXITED(),
96
WEXITSTATUS(), WTERMSIG() */
97
#include <grp.h> /* setgroups() */
98
#include <argz.h> /* argz_add_sep(), argz_next(),
99
argz_delete(), argz_append(),
100
argz_stringify(), argz_add(),
102
#include <netdb.h> /* getnameinfo(), NI_NUMERICHOST,
103
EAI_SYSTEM, gai_strerror() */
79
106
#include <sys/klog.h> /* klogctl() */
107
#endif /* __linux__ */
83
110
/* All Avahi types, constants and functions
112
139
#define PATHDIR "/conf/conf.d/mandos"
113
140
#define SECKEY "seckey.txt"
114
141
#define PUBKEY "pubkey.txt"
142
#define HOOKDIR "/lib/mandos/network-hooks.d"
116
144
bool debug = false;
117
145
static const char mandos_protocol_version[] = "1";
118
146
const char *argp_program_version = "mandos-client " VERSION;
119
const char *argp_program_bug_address = "<mandos@fukt.bsnet.se>";
147
const char *argp_program_bug_address = "<mandos@recompile.se>";
148
static const char sys_class_net[] = "/sys/class/net";
149
char *connect_to = NULL;
150
const char *hookdir = HOOKDIR;
155
/* Doubly linked list that need to be circularly linked when used */
156
typedef struct server{
159
AvahiIfIndex if_index;
161
struct timespec last_seen;
121
166
/* Used for passing in values through the Avahi callback functions */
123
AvahiSimplePoll *simple_poll;
124
168
AvahiServer *server;
125
169
gnutls_certificate_credentials_t cred;
126
170
unsigned int dh_bits;
127
171
gnutls_dh_params_t dh_params;
128
172
const char *priority;
174
server *current_server;
176
size_t interfaces_size;
130
177
} mandos_context;
179
/* global so signal handler can reach it*/
180
AvahiSimplePoll *simple_poll;
182
sig_atomic_t quit_now = 0;
183
int signal_received = 0;
185
/* Function to use when printing errors */
186
void perror_plus(const char *print_text){
188
fprintf(stderr, "Mandos plugin %s: ",
189
program_invocation_short_name);
194
__attribute__((format (gnu_printf, 2, 3), nonnull))
195
int fprintf_plus(FILE *stream, const char *format, ...){
197
va_start (ap, format);
199
TEMP_FAILURE_RETRY(fprintf(stream, "Mandos plugin %s: ",
200
program_invocation_short_name));
201
return (int)TEMP_FAILURE_RETRY(vfprintf(stream, format, ap));
133
* Make room in "buffer" for at least BUFFER_SIZE additional bytes.
134
* "buffer_capacity" is how much is currently allocated,
205
* Make additional room in "buffer" for at least BUFFER_SIZE more
206
* bytes. "buffer_capacity" is how much is currently allocated,
135
207
* "buffer_length" is how much is already used.
137
size_t adjustbuffer(char **buffer, size_t buffer_length,
138
size_t buffer_capacity){
209
__attribute__((nonnull, warn_unused_result))
210
size_t incbuffer(char **buffer, size_t buffer_length,
211
size_t buffer_capacity){
139
212
if(buffer_length + BUFFER_SIZE > buffer_capacity){
140
*buffer = realloc(*buffer, buffer_capacity + BUFFER_SIZE);
213
char *new_buf = realloc(*buffer, buffer_capacity + BUFFER_SIZE);
215
int old_errno = errno;
144
222
buffer_capacity += BUFFER_SIZE;
146
224
return buffer_capacity;
227
/* Add server to set of servers to retry periodically */
228
__attribute__((nonnull, warn_unused_result))
229
bool add_server(const char *ip, in_port_t port, AvahiIfIndex if_index,
230
int af, server **current_server){
232
server *new_server = malloc(sizeof(server));
233
if(new_server == NULL){
234
perror_plus("malloc");
237
*new_server = (server){ .ip = strdup(ip),
239
.if_index = if_index,
241
if(new_server->ip == NULL){
242
perror_plus("strdup");
246
ret = clock_gettime(CLOCK_MONOTONIC, &(new_server->last_seen));
248
perror_plus("clock_gettime");
250
#pragma GCC diagnostic push
251
#pragma GCC diagnostic ignored "-Wcast-qual"
253
free((char *)(new_server->ip));
255
#pragma GCC diagnostic pop
260
/* Special case of first server */
261
if(*current_server == NULL){
262
new_server->next = new_server;
263
new_server->prev = new_server;
264
*current_server = new_server;
266
/* Place the new server last in the list */
267
new_server->next = *current_server;
268
new_server->prev = (*current_server)->prev;
269
new_server->prev->next = new_server;
270
(*current_server)->prev = new_server;
150
276
* Initialize GPGME.
152
static bool init_gpgme(mandos_context *mc, const char *seckey,
153
const char *pubkey, const char *tempdir){
278
__attribute__((nonnull, warn_unused_result))
279
static bool init_gpgme(const char * const seckey,
280
const char * const pubkey,
281
const char * const tempdir,
155
283
gpgme_error_t rc;
156
284
gpgme_engine_info_t engine_info;
160
287
* Helper function to insert pub and seckey to the engine keyring.
162
bool import_key(const char *filename){
289
bool import_key(const char * const filename){
164
292
gpgme_data_t pgp_data;
166
294
fd = (int)TEMP_FAILURE_RETRY(open(filename, O_RDONLY));
172
300
rc = gpgme_data_new_from_fd(&pgp_data, fd);
173
301
if(rc != GPG_ERR_NO_ERROR){
174
fprintf(stderr, "bad gpgme_data_new_from_fd: %s: %s\n",
175
gpgme_strsource(rc), gpgme_strerror(rc));
302
fprintf_plus(stderr, "bad gpgme_data_new_from_fd: %s: %s\n",
303
gpgme_strsource(rc), gpgme_strerror(rc));
179
307
rc = gpgme_op_import(mc->ctx, pgp_data);
180
308
if(rc != GPG_ERR_NO_ERROR){
181
fprintf(stderr, "bad gpgme_op_import: %s: %s\n",
182
gpgme_strsource(rc), gpgme_strerror(rc));
309
fprintf_plus(stderr, "bad gpgme_op_import: %s: %s\n",
310
gpgme_strsource(rc), gpgme_strerror(rc));
314
gpgme_import_result_t import_result
315
= gpgme_op_import_result(mc->ctx);
316
if((import_result->imported < 1
317
or import_result->not_imported > 0)
318
and import_result->unchanged == 0){
319
fprintf_plus(stderr, "bad gpgme_op_import_results:\n");
321
"The total number of considered keys: %d\n",
322
import_result->considered);
324
"The number of keys without user ID: %d\n",
325
import_result->no_user_id);
327
"The total number of imported keys: %d\n",
328
import_result->imported);
329
fprintf_plus(stderr, "The number of imported RSA keys: %d\n",
330
import_result->imported_rsa);
331
fprintf_plus(stderr, "The number of unchanged keys: %d\n",
332
import_result->unchanged);
333
fprintf_plus(stderr, "The number of new user IDs: %d\n",
334
import_result->new_user_ids);
335
fprintf_plus(stderr, "The number of new sub keys: %d\n",
336
import_result->new_sub_keys);
337
fprintf_plus(stderr, "The number of new signatures: %d\n",
338
import_result->new_signatures);
339
fprintf_plus(stderr, "The number of new revocations: %d\n",
340
import_result->new_revocations);
342
"The total number of secret keys read: %d\n",
343
import_result->secret_read);
345
"The number of imported secret keys: %d\n",
346
import_result->secret_imported);
348
"The number of unchanged secret keys: %d\n",
349
import_result->secret_unchanged);
350
fprintf_plus(stderr, "The number of keys not imported: %d\n",
351
import_result->not_imported);
352
for(gpgme_import_status_t import_status
353
= import_result->imports;
354
import_status != NULL;
355
import_status = import_status->next){
356
fprintf_plus(stderr, "Import status for key: %s\n",
358
if(import_status->result != GPG_ERR_NO_ERROR){
359
fprintf_plus(stderr, "Import result: %s: %s\n",
360
gpgme_strsource(import_status->result),
361
gpgme_strerror(import_status->result));
363
fprintf_plus(stderr, "Key status:\n");
365
import_status->status & GPGME_IMPORT_NEW
366
? "The key was new.\n"
367
: "The key was not new.\n");
369
import_status->status & GPGME_IMPORT_UID
370
? "The key contained new user IDs.\n"
371
: "The key did not contain new user IDs.\n");
373
import_status->status & GPGME_IMPORT_SIG
374
? "The key contained new signatures.\n"
375
: "The key did not contain new signatures.\n");
377
import_status->status & GPGME_IMPORT_SUBKEY
378
? "The key contained new sub keys.\n"
379
: "The key did not contain new sub keys.\n");
381
import_status->status & GPGME_IMPORT_SECRET
382
? "The key contained a secret key.\n"
383
: "The key did not contain a secret key.\n");
186
ret = (int)TEMP_FAILURE_RETRY(close(fd));
391
perror_plus("close");
190
393
gpgme_data_release(pgp_data);
195
fprintf(stderr, "Initialize gpgme\n");
398
fprintf_plus(stderr, "Initializing GPGME\n");
199
402
gpgme_check_version(NULL);
200
403
rc = gpgme_engine_check_version(GPGME_PROTOCOL_OpenPGP);
201
404
if(rc != GPG_ERR_NO_ERROR){
202
fprintf(stderr, "bad gpgme_engine_check_version: %s: %s\n",
203
gpgme_strsource(rc), gpgme_strerror(rc));
405
fprintf_plus(stderr, "bad gpgme_engine_check_version: %s: %s\n",
406
gpgme_strsource(rc), gpgme_strerror(rc));
207
/* Set GPGME home directory for the OpenPGP engine only */
410
/* Set GPGME home directory for the OpenPGP engine only */
208
411
rc = gpgme_get_engine_info(&engine_info);
209
412
if(rc != GPG_ERR_NO_ERROR){
210
fprintf(stderr, "bad gpgme_get_engine_info: %s: %s\n",
211
gpgme_strsource(rc), gpgme_strerror(rc));
413
fprintf_plus(stderr, "bad gpgme_get_engine_info: %s: %s\n",
414
gpgme_strsource(rc), gpgme_strerror(rc));
214
417
while(engine_info != NULL){
409
614
/* OpenPGP credentials */
410
gnutls_certificate_allocate_credentials(&mc->cred);
615
ret = gnutls_certificate_allocate_credentials(&mc->cred);
411
616
if(ret != GNUTLS_E_SUCCESS){
412
fprintf(stderr, "GnuTLS memory error: %s\n", /* Spurious warning
416
safer_gnutls_strerror(ret));
417
gnutls_global_deinit();
617
fprintf_plus(stderr, "GnuTLS memory error: %s\n",
618
safer_gnutls_strerror(ret));
422
fprintf(stderr, "Attempting to use OpenPGP public key %s and"
423
" secret key %s as GnuTLS credentials\n", pubkeyfilename,
623
fprintf_plus(stderr, "Attempting to use OpenPGP public key %s and"
624
" secret key %s as GnuTLS credentials\n",
427
629
ret = gnutls_certificate_set_openpgp_key_file
428
630
(mc->cred, pubkeyfilename, seckeyfilename,
429
631
GNUTLS_OPENPGP_FMT_BASE64);
430
632
if(ret != GNUTLS_E_SUCCESS){
432
"Error[%d] while reading the OpenPGP key pair ('%s',"
433
" '%s')\n", ret, pubkeyfilename, seckeyfilename);
434
fprintf(stderr, "The GnuTLS error is: %s\n",
435
safer_gnutls_strerror(ret));
634
"Error[%d] while reading the OpenPGP key pair ('%s',"
635
" '%s')\n", ret, pubkeyfilename, seckeyfilename);
636
fprintf_plus(stderr, "The GnuTLS error is: %s\n",
637
safer_gnutls_strerror(ret));
439
641
/* GnuTLS server initialization */
440
642
ret = gnutls_dh_params_init(&mc->dh_params);
441
643
if(ret != GNUTLS_E_SUCCESS){
442
fprintf(stderr, "Error in GnuTLS DH parameter initialization:"
443
" %s\n", safer_gnutls_strerror(ret));
446
ret = gnutls_dh_params_generate2(mc->dh_params, mc->dh_bits);
447
if(ret != GNUTLS_E_SUCCESS){
448
fprintf(stderr, "Error in GnuTLS prime generation: %s\n",
449
safer_gnutls_strerror(ret));
644
fprintf_plus(stderr, "Error in GnuTLS DH parameter"
645
" initialization: %s\n",
646
safer_gnutls_strerror(ret));
649
/* If a Diffie-Hellman parameters file was given, try to use it */
650
if(dhparamsfilename != NULL){
651
gnutls_datum_t params = { .data = NULL, .size = 0 };
653
int dhpfile = open(dhparamsfilename, O_RDONLY);
656
dhparamsfilename = NULL;
659
size_t params_capacity = 0;
661
params_capacity = incbuffer((char **)¶ms.data,
663
(size_t)params_capacity);
664
if(params_capacity == 0){
665
perror_plus("incbuffer");
668
dhparamsfilename = NULL;
671
ssize_t bytes_read = read(dhpfile,
672
params.data + params.size,
678
/* check bytes_read for failure */
683
dhparamsfilename = NULL;
686
params.size += (unsigned int)bytes_read;
688
ret = close(dhpfile);
690
perror_plus("close");
692
if(params.data == NULL){
693
dhparamsfilename = NULL;
695
if(dhparamsfilename == NULL){
698
ret = gnutls_dh_params_import_pkcs3(mc->dh_params, ¶ms,
699
GNUTLS_X509_FMT_PEM);
700
if(ret != GNUTLS_E_SUCCESS){
701
fprintf_plus(stderr, "Failed to parse DH parameters in file"
702
" \"%s\": %s\n", dhparamsfilename,
703
safer_gnutls_strerror(ret));
704
dhparamsfilename = NULL;
709
if(dhparamsfilename == NULL){
710
if(mc->dh_bits == 0){
711
/* Find out the optimal number of DH bits */
712
/* Try to read the private key file */
713
gnutls_datum_t buffer = { .data = NULL, .size = 0 };
715
int secfile = open(seckeyfilename, O_RDONLY);
720
size_t buffer_capacity = 0;
722
buffer_capacity = incbuffer((char **)&buffer.data,
724
(size_t)buffer_capacity);
725
if(buffer_capacity == 0){
726
perror_plus("incbuffer");
731
ssize_t bytes_read = read(secfile,
732
buffer.data + buffer.size,
738
/* check bytes_read for failure */
745
buffer.size += (unsigned int)bytes_read;
749
/* If successful, use buffer to parse private key */
750
gnutls_sec_param_t sec_param = GNUTLS_SEC_PARAM_ULTRA;
751
if(buffer.data != NULL){
753
gnutls_openpgp_privkey_t privkey = NULL;
754
ret = gnutls_openpgp_privkey_init(&privkey);
755
if(ret != GNUTLS_E_SUCCESS){
756
fprintf_plus(stderr, "Error initializing OpenPGP key"
758
safer_gnutls_strerror(ret));
762
ret = gnutls_openpgp_privkey_import
763
(privkey, &buffer, GNUTLS_OPENPGP_FMT_BASE64, "", 0);
764
if(ret != GNUTLS_E_SUCCESS){
765
fprintf_plus(stderr, "Error importing OpenPGP key : %s",
766
safer_gnutls_strerror(ret));
772
/* Use private key to suggest an appropriate
774
sec_param = gnutls_openpgp_privkey_sec_param(privkey);
775
gnutls_openpgp_privkey_deinit(privkey);
777
fprintf_plus(stderr, "This OpenPGP key implies using"
778
" a GnuTLS security parameter \"%s\".\n",
779
safe_string(gnutls_sec_param_get_name
785
if(sec_param == GNUTLS_SEC_PARAM_UNKNOWN){
786
/* Err on the side of caution */
787
sec_param = GNUTLS_SEC_PARAM_ULTRA;
789
fprintf_plus(stderr, "Falling back to security parameter"
791
safe_string(gnutls_sec_param_get_name
796
uret = gnutls_sec_param_to_pk_bits(GNUTLS_PK_DH, sec_param);
800
fprintf_plus(stderr, "A \"%s\" GnuTLS security parameter"
801
" implies %u DH bits; using that.\n",
802
safe_string(gnutls_sec_param_get_name
807
fprintf_plus(stderr, "Failed to get implied number of DH"
808
" bits for security parameter \"%s\"): %s\n",
809
safe_string(gnutls_sec_param_get_name
811
safer_gnutls_strerror(ret));
815
fprintf_plus(stderr, "DH bits explicitly set to %u\n",
818
ret = gnutls_dh_params_generate2(mc->dh_params, mc->dh_bits);
819
if(ret != GNUTLS_E_SUCCESS){
820
fprintf_plus(stderr, "Error in GnuTLS prime generation (%u"
821
" bits): %s\n", mc->dh_bits,
822
safer_gnutls_strerror(ret));
453
826
gnutls_certificate_set_dh_params(mc->cred, mc->dh_params);
506
894
static void empty_log(__attribute__((unused)) AvahiLogLevel level,
507
895
__attribute__((unused)) const char *txt){}
897
/* Set effective uid to 0, return errno */
898
__attribute__((warn_unused_result))
899
int raise_privileges(void){
900
int old_errno = errno;
902
if(seteuid(0) == -1){
909
/* Set effective and real user ID to 0. Return errno. */
910
__attribute__((warn_unused_result))
911
int raise_privileges_permanently(void){
912
int old_errno = errno;
913
int ret = raise_privileges();
925
/* Set effective user ID to unprivileged saved user ID */
926
__attribute__((warn_unused_result))
927
int lower_privileges(void){
928
int old_errno = errno;
930
if(seteuid(uid) == -1){
937
/* Lower privileges permanently */
938
__attribute__((warn_unused_result))
939
int lower_privileges_permanently(void){
940
int old_errno = errno;
942
if(setuid(uid) == -1){
949
/* Helper function to add_local_route() and delete_local_route() */
950
__attribute__((nonnull, warn_unused_result))
951
static bool add_delete_local_route(const bool add,
953
AvahiIfIndex if_index){
955
char helper[] = "mandos-client-iprouteadddel";
956
char add_arg[] = "add";
957
char delete_arg[] = "delete";
958
char debug_flag[] = "--debug";
959
char *pluginhelperdir = getenv("MANDOSPLUGINHELPERDIR");
960
if(pluginhelperdir == NULL){
962
fprintf_plus(stderr, "MANDOSPLUGINHELPERDIR environment"
963
" variable not set; cannot run helper\n");
968
char interface[IF_NAMESIZE];
969
if(if_indextoname((unsigned int)if_index, interface) == NULL){
970
perror_plus("if_indextoname");
974
int devnull = (int)TEMP_FAILURE_RETRY(open("/dev/null", O_RDONLY));
976
perror_plus("open(\"/dev/null\", O_RDONLY)");
982
/* Raise privileges */
983
errno = raise_privileges_permanently();
985
perror_plus("Failed to raise privileges");
986
/* _exit(EX_NOPERM); */
992
perror_plus("setgid");
995
/* Reset supplementary groups */
997
ret = setgroups(0, NULL);
999
perror_plus("setgroups");
1003
ret = dup2(devnull, STDIN_FILENO);
1005
perror_plus("dup2(devnull, STDIN_FILENO)");
1008
ret = close(devnull);
1010
perror_plus("close");
1013
ret = dup2(STDERR_FILENO, STDOUT_FILENO);
1015
perror_plus("dup2(STDERR_FILENO, STDOUT_FILENO)");
1018
int helperdir_fd = (int)TEMP_FAILURE_RETRY(open(pluginhelperdir,
1023
if(helperdir_fd == -1){
1024
perror_plus("open");
1025
_exit(EX_UNAVAILABLE);
1027
int helper_fd = (int)TEMP_FAILURE_RETRY(openat(helperdir_fd,
1029
if(helper_fd == -1){
1030
perror_plus("openat");
1031
close(helperdir_fd);
1032
_exit(EX_UNAVAILABLE);
1034
close(helperdir_fd);
1036
#pragma GCC diagnostic push
1037
#pragma GCC diagnostic ignored "-Wcast-qual"
1039
if(fexecve(helper_fd, (char *const [])
1040
{ helper, add ? add_arg : delete_arg, (char *)address,
1041
interface, debug ? debug_flag : NULL, NULL },
1044
#pragma GCC diagnostic pop
1046
perror_plus("fexecve");
1047
_exit(EXIT_FAILURE);
1051
perror_plus("fork");
1058
pret = waitpid(pid, &status, 0);
1059
if(pret == -1 and errno == EINTR and quit_now){
1060
int errno_raising = 0;
1061
if((errno = raise_privileges()) != 0){
1062
errno_raising = errno;
1063
perror_plus("Failed to raise privileges in order to"
1064
" kill helper program");
1066
if(kill(pid, SIGTERM) == -1){
1067
perror_plus("kill");
1069
if((errno_raising == 0) and (errno = lower_privileges()) != 0){
1070
perror_plus("Failed to lower privileges after killing"
1075
} while(pret == -1 and errno == EINTR);
1077
perror_plus("waitpid");
1080
if(WIFEXITED(status)){
1081
if(WEXITSTATUS(status) != 0){
1082
fprintf_plus(stderr, "Error: iprouteadddel exited"
1083
" with status %d\n", WEXITSTATUS(status));
1088
if(WIFSIGNALED(status)){
1089
fprintf_plus(stderr, "Error: iprouteadddel died by"
1090
" signal %d\n", WTERMSIG(status));
1093
fprintf_plus(stderr, "Error: iprouteadddel crashed\n");
1097
__attribute__((nonnull, warn_unused_result))
1098
static bool add_local_route(const char *address,
1099
AvahiIfIndex if_index){
1101
fprintf_plus(stderr, "Adding route to %s\n", address);
1103
return add_delete_local_route(true, address, if_index);
1106
__attribute__((nonnull, warn_unused_result))
1107
static bool delete_local_route(const char *address,
1108
AvahiIfIndex if_index){
1110
fprintf_plus(stderr, "Removing route to %s\n", address);
1112
return add_delete_local_route(false, address, if_index);
509
1115
/* Called when a Mandos server is found */
510
static int start_mandos_communication(const char *ip, uint16_t port,
1116
__attribute__((nonnull, warn_unused_result))
1117
static int start_mandos_communication(const char *ip, in_port_t port,
511
1118
AvahiIfIndex if_index,
1119
int af, mandos_context *mc){
1120
int ret, tcp_sd = -1;
515
union { struct sockaddr in; struct sockaddr_in6 in6; } to;
1122
struct sockaddr_storage to;
516
1123
char *buffer = NULL;
517
char *decrypted_buffer;
1124
char *decrypted_buffer = NULL;
518
1125
size_t buffer_length = 0;
519
1126
size_t buffer_capacity = 0;
520
ssize_t decrypted_buffer_size;
523
char interface[IF_NAMESIZE];
524
1129
gnutls_session_t session;
526
ret = init_gnutls_session(mc, &session);
1130
int pf; /* Protocol family */
1131
bool route_added = false;
1148
fprintf_plus(stderr, "Bad address family: %d\n", af);
1153
/* If the interface is specified and we have a list of interfaces */
1154
if(if_index != AVAHI_IF_UNSPEC and mc->interfaces != NULL){
1155
/* Check if the interface is one of the interfaces we are using */
1158
char *interface = NULL;
1159
while((interface = argz_next(mc->interfaces,
1160
mc->interfaces_size,
1162
if(if_nametoindex(interface) == (unsigned int)if_index){
1169
/* This interface does not match any in the list, so we don't
1170
connect to the server */
1172
char interface[IF_NAMESIZE];
1173
if(if_indextoname((unsigned int)if_index, interface) == NULL){
1174
perror_plus("if_indextoname");
1176
fprintf_plus(stderr, "Skipping server on non-used interface"
1178
if_indextoname((unsigned int)if_index,
1186
ret = init_gnutls_session(&session, mc);
532
fprintf(stderr, "Setting up a tcp connection to %s, port %" PRIu16
1192
fprintf_plus(stderr, "Setting up a TCP connection to %s, port %"
1193
PRIuMAX "\n", ip, (uintmax_t)port);
536
tcp_sd = socket(PF_INET6, SOCK_STREAM, 0);
1196
tcp_sd = socket(pf, SOCK_STREAM | SOCK_CLOEXEC, 0);
543
if(if_indextoname((unsigned int)if_index, interface) == NULL){
544
perror("if_indextoname");
547
fprintf(stderr, "Binding to interface %s\n", interface);
550
memset(&to, 0, sizeof(to));
551
to.in6.sin6_family = AF_INET6;
552
/* It would be nice to have a way to detect if we were passed an
553
IPv4 address here. Now we assume an IPv6 address. */
554
ret = inet_pton(AF_INET6, ip, &to.in6.sin6_addr);
1199
perror_plus("socket");
1210
struct sockaddr_in6 *to6 = (struct sockaddr_in6 *)&to;
1211
*to6 = (struct sockaddr_in6){ .sin6_family = (sa_family_t)af };
1212
ret = inet_pton(af, ip, &to6->sin6_addr);
1214
struct sockaddr_in *to4 = (struct sockaddr_in *)&to;
1215
*to4 = (struct sockaddr_in){ .sin_family = (sa_family_t)af };
1216
ret = inet_pton(af, ip, &to4->sin_addr);
1220
perror_plus("inet_pton");
560
fprintf(stderr, "Bad address: %s\n", ip);
563
to.in6.sin6_port = htons(port); /* Spurious warnings from
565
-Wunreachable-code */
1226
fprintf_plus(stderr, "Bad address: %s\n", ip);
1231
((struct sockaddr_in6 *)&to)->sin6_port = htons(port);
1232
if(IN6_IS_ADDR_LINKLOCAL
1233
(&((struct sockaddr_in6 *)&to)->sin6_addr)){
1234
if(if_index == AVAHI_IF_UNSPEC){
1235
fprintf_plus(stderr, "An IPv6 link-local address is"
1236
" incomplete without a network interface\n");
1240
/* Set the network interface number as scope */
1241
((struct sockaddr_in6 *)&to)->sin6_scope_id = (uint32_t)if_index;
1244
((struct sockaddr_in *)&to)->sin_port = htons(port);
567
to.in6.sin6_scope_id = (uint32_t)if_index;
570
fprintf(stderr, "Connection to: %s, port %" PRIu16 "\n", ip,
572
char addrstr[INET6_ADDRSTRLEN] = "";
573
if(inet_ntop(to.in6.sin6_family, &(to.in6.sin6_addr), addrstr,
574
sizeof(addrstr)) == NULL){
577
if(strcmp(addrstr, ip) != 0){
578
fprintf(stderr, "Canonical address form: %s\n", addrstr);
583
ret = connect(tcp_sd, &to.in, sizeof(to));
1253
if(af == AF_INET6 and if_index != AVAHI_IF_UNSPEC){
1254
char interface[IF_NAMESIZE];
1255
if(if_indextoname((unsigned int)if_index, interface) == NULL){
1256
perror_plus("if_indextoname");
1258
fprintf_plus(stderr, "Connection to: %s%%%s, port %" PRIuMAX
1259
"\n", ip, interface, (uintmax_t)port);
1262
fprintf_plus(stderr, "Connection to: %s, port %" PRIuMAX "\n",
1263
ip, (uintmax_t)port);
1265
char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?
1266
INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";
1268
ret = getnameinfo((struct sockaddr *)&to,
1269
sizeof(struct sockaddr_in6),
1270
addrstr, sizeof(addrstr), NULL, 0,
1273
ret = getnameinfo((struct sockaddr *)&to,
1274
sizeof(struct sockaddr_in),
1275
addrstr, sizeof(addrstr), NULL, 0,
1278
if(ret == EAI_SYSTEM){
1279
perror_plus("getnameinfo");
1280
} else if(ret != 0) {
1281
fprintf_plus(stderr, "getnameinfo: %s", gai_strerror(ret));
1282
} else if(strcmp(addrstr, ip) != 0){
1283
fprintf_plus(stderr, "Canonical address form: %s\n", addrstr);
1294
ret = connect(tcp_sd, (struct sockaddr *)&to,
1295
sizeof(struct sockaddr_in6));
1297
ret = connect(tcp_sd, (struct sockaddr *)&to, /* IPv4 */
1298
sizeof(struct sockaddr_in));
1301
if(((errno == ENETUNREACH) or (errno == EHOSTUNREACH))
1302
and if_index != AVAHI_IF_UNSPEC
1303
and connect_to == NULL
1304
and not route_added and
1305
((af == AF_INET6 and not
1306
IN6_IS_ADDR_LINKLOCAL(&(((struct sockaddr_in6 *)
1308
or (af == AF_INET and
1309
/* Not a a IPv4LL address */
1310
(ntohl(((struct sockaddr_in *)&to)->sin_addr.s_addr)
1311
& 0xFFFF0000L) != 0xA9FE0000L))){
1312
/* Work around Avahi bug - Avahi does not announce link-local
1313
addresses if it has a global address, so local hosts with
1314
*only* a link-local address (e.g. Mandos clients) cannot
1315
connect to a Mandos server announced by Avahi on a server
1316
host with a global address. Work around this by retrying
1317
with an explicit route added with the server's address.
1319
Avahi bug reference:
1320
https://lists.freedesktop.org/archives/avahi/2010-February/001833.html
1321
https://bugs.debian.org/587961
1324
fprintf_plus(stderr, "Mandos server unreachable, trying"
1328
route_added = add_local_route(ip, if_index);
1334
if(errno != ECONNREFUSED or debug){
1336
perror_plus("connect");
589
1349
const char *out = mandos_protocol_version;
815
1688
case AVAHI_BROWSER_ALL_FOR_NOW:
816
1689
case AVAHI_BROWSER_CACHE_EXHAUSTED:
818
fprintf(stderr, "No Mandos server found, still searching...\n");
1691
fprintf_plus(stderr, "No Mandos server found, still"
1698
/* Signal handler that stops main loop after SIGTERM */
1699
static void handle_sigterm(int sig){
1704
signal_received = sig;
1705
int old_errno = errno;
1706
/* set main loop to exit */
1707
if(simple_poll != NULL){
1708
avahi_simple_poll_quit(simple_poll);
1713
__attribute__((nonnull, warn_unused_result))
1714
bool get_flags(const char *ifname, struct ifreq *ifr){
1718
int s = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1721
perror_plus("socket");
1725
strncpy(ifr->ifr_name, ifname, IF_NAMESIZE);
1726
ifr->ifr_name[IF_NAMESIZE-1] = '\0'; /* NUL terminate */
1727
ret = ioctl(s, SIOCGIFFLAGS, ifr);
1731
perror_plus("ioctl SIOCGIFFLAGS");
1734
if((close(s) == -1) and debug){
1736
perror_plus("close");
1741
if((close(s) == -1) and debug){
1743
perror_plus("close");
1749
__attribute__((nonnull, warn_unused_result))
1750
bool good_flags(const char *ifname, const struct ifreq *ifr){
1752
/* Reject the loopback device */
1753
if(ifr->ifr_flags & IFF_LOOPBACK){
1755
fprintf_plus(stderr, "Rejecting loopback interface \"%s\"\n",
1760
/* Accept point-to-point devices only if connect_to is specified */
1761
if(connect_to != NULL and (ifr->ifr_flags & IFF_POINTOPOINT)){
1763
fprintf_plus(stderr, "Accepting point-to-point interface"
1764
" \"%s\"\n", ifname);
1768
/* Otherwise, reject non-broadcast-capable devices */
1769
if(not (ifr->ifr_flags & IFF_BROADCAST)){
1771
fprintf_plus(stderr, "Rejecting non-broadcast interface"
1772
" \"%s\"\n", ifname);
1776
/* Reject non-ARP interfaces (including dummy interfaces) */
1777
if(ifr->ifr_flags & IFF_NOARP){
1779
fprintf_plus(stderr, "Rejecting non-ARP interface \"%s\"\n",
1785
/* Accept this device */
1787
fprintf_plus(stderr, "Interface \"%s\" is good\n", ifname);
1793
* This function determines if a directory entry in /sys/class/net
1794
* corresponds to an acceptable network device.
1795
* (This function is passed to scandir(3) as a filter function.)
1797
__attribute__((nonnull, warn_unused_result))
1798
int good_interface(const struct dirent *if_entry){
1799
if(if_entry->d_name[0] == '.'){
1804
if(not get_flags(if_entry->d_name, &ifr)){
1806
fprintf_plus(stderr, "Failed to get flags for interface "
1807
"\"%s\"\n", if_entry->d_name);
1812
if(not good_flags(if_entry->d_name, &ifr)){
1819
* This function determines if a network interface is up.
1821
__attribute__((nonnull, warn_unused_result))
1822
bool interface_is_up(const char *interface){
1824
if(not get_flags(interface, &ifr)){
1826
fprintf_plus(stderr, "Failed to get flags for interface "
1827
"\"%s\"\n", interface);
1832
return (bool)(ifr.ifr_flags & IFF_UP);
1836
* This function determines if a network interface is running
1838
__attribute__((nonnull, warn_unused_result))
1839
bool interface_is_running(const char *interface){
1841
if(not get_flags(interface, &ifr)){
1843
fprintf_plus(stderr, "Failed to get flags for interface "
1844
"\"%s\"\n", interface);
1849
return (bool)(ifr.ifr_flags & IFF_RUNNING);
1852
__attribute__((nonnull, pure, warn_unused_result))
1853
int notdotentries(const struct dirent *direntry){
1854
/* Skip "." and ".." */
1855
if(direntry->d_name[0] == '.'
1856
and (direntry->d_name[1] == '\0'
1857
or (direntry->d_name[1] == '.'
1858
and direntry->d_name[2] == '\0'))){
1864
/* Is this directory entry a runnable program? */
1865
__attribute__((nonnull, warn_unused_result))
1866
int runnable_hook(const struct dirent *direntry){
1871
if((direntry->d_name)[0] == '\0'){
1876
sret = strspn(direntry->d_name, "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
1877
"abcdefghijklmnopqrstuvwxyz"
1880
if((direntry->d_name)[sret] != '\0'){
1881
/* Contains non-allowed characters */
1883
fprintf_plus(stderr, "Ignoring hook \"%s\" with bad name\n",
1889
ret = fstatat(hookdir_fd, direntry->d_name, &st, 0);
1892
perror_plus("Could not stat hook");
1896
if(not (S_ISREG(st.st_mode))){
1897
/* Not a regular file */
1899
fprintf_plus(stderr, "Ignoring hook \"%s\" - not a file\n",
1904
if(not (st.st_mode & (S_IXUSR | S_IXGRP | S_IXOTH))){
1905
/* Not executable */
1907
fprintf_plus(stderr, "Ignoring hook \"%s\" - not executable\n",
1913
fprintf_plus(stderr, "Hook \"%s\" is acceptable\n",
1919
__attribute__((nonnull, warn_unused_result))
1920
int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,
1921
mandos_context *mc){
1923
struct timespec now;
1924
struct timespec waited_time;
1925
intmax_t block_time;
1928
if(mc->current_server == NULL){
1930
fprintf_plus(stderr, "Wait until first server is found."
1933
ret = avahi_simple_poll_iterate(s, -1);
1936
fprintf_plus(stderr, "Check current_server if we should run"
1939
/* the current time */
1940
ret = clock_gettime(CLOCK_MONOTONIC, &now);
1942
perror_plus("clock_gettime");
1945
/* Calculating in ms how long time between now and server
1946
who we visted longest time ago. Now - last seen. */
1947
waited_time.tv_sec = (now.tv_sec
1948
- mc->current_server->last_seen.tv_sec);
1949
waited_time.tv_nsec = (now.tv_nsec
1950
- mc->current_server->last_seen.tv_nsec);
1951
/* total time is 10s/10,000ms.
1952
Converting to s from ms by dividing by 1,000,
1953
and ns to ms by dividing by 1,000,000. */
1954
block_time = ((retry_interval
1955
- ((intmax_t)waited_time.tv_sec * 1000))
1956
- ((intmax_t)waited_time.tv_nsec / 1000000));
1959
fprintf_plus(stderr, "Blocking for %" PRIdMAX " ms\n",
1963
if(block_time <= 0){
1964
ret = start_mandos_communication(mc->current_server->ip,
1965
mc->current_server->port,
1966
mc->current_server->if_index,
1967
mc->current_server->af, mc);
1969
avahi_simple_poll_quit(s);
1972
ret = clock_gettime(CLOCK_MONOTONIC,
1973
&mc->current_server->last_seen);
1975
perror_plus("clock_gettime");
1978
mc->current_server = mc->current_server->next;
1979
block_time = 0; /* Call avahi to find new Mandos
1980
servers, but don't block */
1983
ret = avahi_simple_poll_iterate(s, (int)block_time);
1986
if(ret > 0 or errno != EINTR){
1987
return (ret != 1) ? ret : 0;
1993
__attribute__((nonnull))
1994
void run_network_hooks(const char *mode, const char *interface,
1996
struct dirent **direntries = NULL;
1997
if(hookdir_fd == -1){
1998
hookdir_fd = open(hookdir, O_RDONLY | O_DIRECTORY | O_PATH
2000
if(hookdir_fd == -1){
2001
if(errno == ENOENT){
2003
fprintf_plus(stderr, "Network hook directory \"%s\" not"
2004
" found\n", hookdir);
2007
perror_plus("open");
2012
int devnull = (int)TEMP_FAILURE_RETRY(open("/dev/null", O_RDONLY));
2014
perror_plus("open(\"/dev/null\", O_RDONLY)");
2017
int numhooks = scandirat(hookdir_fd, ".", &direntries,
2018
runnable_hook, alphasort);
2020
perror_plus("scandir");
2024
struct dirent *direntry;
2026
for(int i = 0; i < numhooks; i++){
2027
direntry = direntries[i];
2029
fprintf_plus(stderr, "Running network hook \"%s\"\n",
2032
pid_t hook_pid = fork();
2035
/* Raise privileges */
2036
errno = raise_privileges_permanently();
2038
perror_plus("Failed to raise privileges");
2045
perror_plus("setgid");
2048
/* Reset supplementary groups */
2050
ret = setgroups(0, NULL);
2052
perror_plus("setgroups");
2055
ret = setenv("MANDOSNETHOOKDIR", hookdir, 1);
2057
perror_plus("setenv");
2060
ret = setenv("DEVICE", interface, 1);
2062
perror_plus("setenv");
2065
ret = setenv("VERBOSITY", debug ? "1" : "0", 1);
2067
perror_plus("setenv");
2070
ret = setenv("MODE", mode, 1);
2072
perror_plus("setenv");
2076
ret = asprintf(&delaystring, "%f", (double)delay);
2078
perror_plus("asprintf");
2081
ret = setenv("DELAY", delaystring, 1);
2084
perror_plus("setenv");
2088
if(connect_to != NULL){
2089
ret = setenv("CONNECT", connect_to, 1);
2091
perror_plus("setenv");
2095
int hook_fd = (int)TEMP_FAILURE_RETRY(openat(hookdir_fd,
2099
perror_plus("openat");
2100
_exit(EXIT_FAILURE);
2102
if(close(hookdir_fd) == -1){
2103
perror_plus("close");
2104
_exit(EXIT_FAILURE);
2106
ret = dup2(devnull, STDIN_FILENO);
2108
perror_plus("dup2(devnull, STDIN_FILENO)");
2111
ret = close(devnull);
2113
perror_plus("close");
2116
ret = dup2(STDERR_FILENO, STDOUT_FILENO);
2118
perror_plus("dup2(STDERR_FILENO, STDOUT_FILENO)");
2121
if(fexecve(hook_fd, (char *const []){ direntry->d_name, NULL },
2123
perror_plus("fexecve");
2124
_exit(EXIT_FAILURE);
2128
perror_plus("fork");
2133
if(TEMP_FAILURE_RETRY(waitpid(hook_pid, &status, 0)) == -1){
2134
perror_plus("waitpid");
2138
if(WIFEXITED(status)){
2139
if(WEXITSTATUS(status) != 0){
2140
fprintf_plus(stderr, "Warning: network hook \"%s\" exited"
2141
" with status %d\n", direntry->d_name,
2142
WEXITSTATUS(status));
2146
} else if(WIFSIGNALED(status)){
2147
fprintf_plus(stderr, "Warning: network hook \"%s\" died by"
2148
" signal %d\n", direntry->d_name,
2153
fprintf_plus(stderr, "Warning: network hook \"%s\""
2154
" crashed\n", direntry->d_name);
2160
fprintf_plus(stderr, "Network hook \"%s\" ran successfully\n",
2166
if(close(hookdir_fd) == -1){
2167
perror_plus("close");
2174
__attribute__((nonnull, warn_unused_result))
2175
int bring_up_interface(const char *const interface,
2177
int old_errno = errno;
2179
struct ifreq network;
2180
unsigned int if_index = if_nametoindex(interface);
2182
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
2192
if(not interface_is_up(interface)){
2194
int ioctl_errno = 0;
2195
if(not get_flags(interface, &network)){
2197
fprintf_plus(stderr, "Failed to get flags for interface "
2198
"\"%s\"\n", interface);
2202
network.ifr_flags |= IFF_UP; /* set flag */
2204
int sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
2207
perror_plus("socket");
2215
perror_plus("close");
2222
fprintf_plus(stderr, "Bringing up interface \"%s\"\n",
2226
/* Raise privileges */
2227
ret_errno = raise_privileges();
2230
perror_plus("Failed to raise privileges");
2235
bool restore_loglevel = false;
2237
/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO
2238
messages about the network interface to mess up the prompt */
2239
ret_linux = klogctl(8, NULL, 5);
2240
if(ret_linux == -1){
2241
perror_plus("klogctl");
2243
restore_loglevel = true;
2246
#endif /* __linux__ */
2247
int ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
2248
ioctl_errno = errno;
2250
if(restore_loglevel){
2251
ret_linux = klogctl(7, NULL, 0);
2252
if(ret_linux == -1){
2253
perror_plus("klogctl");
2256
#endif /* __linux__ */
2258
/* If raise_privileges() succeeded above */
2260
/* Lower privileges */
2261
ret_errno = lower_privileges();
2264
perror_plus("Failed to lower privileges");
2268
/* Close the socket */
2271
perror_plus("close");
2274
if(ret_setflags == -1){
2275
errno = ioctl_errno;
2276
perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");
2281
fprintf_plus(stderr, "Interface \"%s\" is already up; good\n",
2285
/* Sleep checking until interface is running.
2286
Check every 0.25s, up to total time of delay */
2287
for(int i = 0; i < delay * 4; i++){
2288
if(interface_is_running(interface)){
2291
struct timespec sleeptime = { .tv_nsec = 250000000 };
2292
ret = nanosleep(&sleeptime, NULL);
2293
if(ret == -1 and errno != EINTR){
2294
perror_plus("nanosleep");
2302
__attribute__((nonnull, warn_unused_result))
2303
int take_down_interface(const char *const interface){
2304
int old_errno = errno;
2305
struct ifreq network;
2306
unsigned int if_index = if_nametoindex(interface);
2308
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
2312
if(interface_is_up(interface)){
2314
int ioctl_errno = 0;
2315
if(not get_flags(interface, &network) and debug){
2317
fprintf_plus(stderr, "Failed to get flags for interface "
2318
"\"%s\"\n", interface);
2322
network.ifr_flags &= ~(short)IFF_UP; /* clear flag */
2324
int sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
2327
perror_plus("socket");
2333
fprintf_plus(stderr, "Taking down interface \"%s\"\n",
2337
/* Raise privileges */
2338
ret_errno = raise_privileges();
2341
perror_plus("Failed to raise privileges");
2344
int ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
2345
ioctl_errno = errno;
2347
/* If raise_privileges() succeeded above */
2349
/* Lower privileges */
2350
ret_errno = lower_privileges();
2353
perror_plus("Failed to lower privileges");
2357
/* Close the socket */
2358
int ret = close(sd);
2360
perror_plus("close");
2363
if(ret_setflags == -1){
2364
errno = ioctl_errno;
2365
perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");
2370
fprintf_plus(stderr, "Interface \"%s\" is already down; odd\n",
824
2378
int main(int argc, char *argv[]){
2379
mandos_context mc = { .server = NULL, .dh_bits = 0,
2380
.priority = "SECURE256:!CTYPE-X.509"
2381
":+CTYPE-OPENPGP:!RSA:+SIGN-DSA-SHA256",
2382
.current_server = NULL, .interfaces = NULL,
2383
.interfaces_size = 0 };
825
2384
AvahiSServiceBrowser *sb = NULL;
828
2387
intmax_t tmpmax;
830
2389
int exitcode = EXIT_SUCCESS;
831
const char *interface = "eth0";
832
struct ifreq network;
836
char *connect_to = NULL;
837
char tempdir[] = "/tmp/mandosXXXXXX";
838
bool tempdir_created = false;
2390
char *interfaces_to_take_down = NULL;
2391
size_t interfaces_to_take_down_size = 0;
2392
char run_tempdir[] = "/run/tmp/mandosXXXXXX";
2393
char old_tempdir[] = "/tmp/mandosXXXXXX";
2394
char *tempdir = NULL;
839
2395
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
840
2396
const char *seckey = PATHDIR "/" SECKEY;
841
2397
const char *pubkey = PATHDIR "/" PUBKEY;
2398
const char *dh_params_file = NULL;
2399
char *interfaces_hooks = NULL;
843
mandos_context mc = { .simple_poll = NULL, .server = NULL,
844
.dh_bits = 1024, .priority = "SECURE256"
845
":!CTYPE-X.509:+CTYPE-OPENPGP" };
846
2401
bool gnutls_initialized = false;
847
2402
bool gpgme_initialized = false;
2404
double retry_interval = 10; /* 10s between trying a server and
2405
retrying the same server again */
2407
struct sigaction old_sigterm_action = { .sa_handler = SIG_DFL };
2408
struct sigaction sigterm_action = { .sa_handler = handle_sigterm };
2413
/* Lower any group privileges we might have, just to be safe */
2417
perror_plus("setgid");
2420
/* Lower user privileges (temporarily) */
2424
perror_plus("seteuid");
851
2432
struct argp_option options[] = {
905
2513
case 129: /* --dh-bits */
906
ret = sscanf(arg, "%" SCNdMAX "%n", &tmpmax, &numchars);
907
if(ret < 1 or tmpmax != (typeof(mc.dh_bits))tmpmax
908
or arg[numchars] != '\0'){
909
fprintf(stderr, "Bad number of DH bits\n");
2515
tmpmax = strtoimax(arg, &tmp, 10);
2516
if(errno != 0 or tmp == arg or *tmp != '\0'
2517
or tmpmax != (typeof(mc.dh_bits))tmpmax){
2518
argp_error(state, "Bad number of DH bits");
912
2520
mc.dh_bits = (typeof(mc.dh_bits))tmpmax;
2522
case 134: /* --dh-params */
2523
dh_params_file = arg;
914
2525
case 130: /* --priority */
915
2526
mc.priority = arg;
917
2528
case 131: /* --delay */
918
ret = sscanf(arg, "%lf%n", &delay, &numchars);
919
if(ret < 1 or arg[numchars] != '\0'){
920
fprintf(stderr, "Bad delay\n");
2530
delay = strtof(arg, &tmp);
2531
if(errno != 0 or tmp == arg or *tmp != '\0'){
2532
argp_error(state, "Bad delay");
2534
case 132: /* --retry */
2536
retry_interval = strtod(arg, &tmp);
2537
if(errno != 0 or tmp == arg or *tmp != '\0'
2538
or (retry_interval * 1000) > INT_MAX
2539
or retry_interval < 0){
2540
argp_error(state, "Bad retry interval");
2543
case 133: /* --network-hook-dir */
2547
* These reproduce what we would get without ARGP_NO_HELP
2549
case '?': /* --help */
2550
argp_state_help(state, state->out_stream,
2551
(ARGP_HELP_STD_HELP | ARGP_HELP_EXIT_ERR)
2552
& ~(unsigned int)ARGP_HELP_EXIT_OK);
2553
case -3: /* --usage */
2554
argp_state_help(state, state->out_stream,
2555
ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);
2556
case 'V': /* --version */
2557
fprintf_plus(state->out_stream, "%s\n", argp_program_version);
2558
exit(argp_err_exit_status);
929
2561
return ARGP_ERR_UNKNOWN;
934
2566
struct argp argp = { .options = options, .parser = parse_opt,
936
2568
.doc = "Mandos client -- Get and decrypt"
937
2569
" passwords from a Mandos server" };
938
ret = argp_parse(&argp, argc, argv, 0, 0, NULL);
939
if(ret == ARGP_ERR_UNKNOWN){
940
fprintf(stderr, "Unknown error while parsing arguments\n");
941
exitcode = EXIT_FAILURE;
2570
ret_errno = argp_parse(&argp, argc, argv,
2571
ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);
2578
perror_plus("argp_parse");
2579
exitcode = EX_OSERR;
2582
exitcode = EX_USAGE;
946
/* If the interface is down, bring it up */
949
/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO
950
messages to mess up the prompt */
951
ret = klogctl(8, NULL, 5);
2588
/* Work around Debian bug #633582:
2589
<https://bugs.debian.org/633582> */
957
sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
960
exitcode = EXIT_FAILURE;
962
ret = klogctl(7, NULL, 0);
969
strcpy(network.ifr_name, interface);
970
ret = ioctl(sd, SIOCGIFFLAGS, &network);
972
perror("ioctl SIOCGIFFLAGS");
974
ret = klogctl(7, NULL, 0);
979
exitcode = EXIT_FAILURE;
982
if((network.ifr_flags & IFF_UP) == 0){
983
network.ifr_flags |= IFF_UP;
984
ret = ioctl(sd, SIOCSIFFLAGS, &network);
986
perror("ioctl SIOCSIFFLAGS");
987
exitcode = EXIT_FAILURE;
989
ret = klogctl(7, NULL, 0);
2591
/* Re-raise privileges */
2592
ret = raise_privileges();
2595
perror_plus("Failed to raise privileges");
2599
if(strcmp(seckey, PATHDIR "/" SECKEY) == 0){
2600
int seckey_fd = open(seckey, O_RDONLY);
2601
if(seckey_fd == -1){
2602
perror_plus("open");
2604
ret = (int)TEMP_FAILURE_RETRY(fstat(seckey_fd, &st));
2606
perror_plus("fstat");
2608
if(S_ISREG(st.st_mode)
2609
and st.st_uid == 0 and st.st_gid == 0){
2610
ret = fchown(seckey_fd, uid, gid);
2612
perror_plus("fchown");
2620
if(strcmp(pubkey, PATHDIR "/" PUBKEY) == 0){
2621
int pubkey_fd = open(pubkey, O_RDONLY);
2622
if(pubkey_fd == -1){
2623
perror_plus("open");
2625
ret = (int)TEMP_FAILURE_RETRY(fstat(pubkey_fd, &st));
2627
perror_plus("fstat");
2629
if(S_ISREG(st.st_mode)
2630
and st.st_uid == 0 and st.st_gid == 0){
2631
ret = fchown(pubkey_fd, uid, gid);
2633
perror_plus("fchown");
2641
if(dh_params_file != NULL
2642
and strcmp(dh_params_file, PATHDIR "/dhparams.pem" ) == 0){
2643
int dhparams_fd = open(dh_params_file, O_RDONLY);
2644
if(dhparams_fd == -1){
2645
perror_plus("open");
2647
ret = (int)TEMP_FAILURE_RETRY(fstat(dhparams_fd, &st));
2649
perror_plus("fstat");
2651
if(S_ISREG(st.st_mode)
2652
and st.st_uid == 0 and st.st_gid == 0){
2653
ret = fchown(dhparams_fd, uid, gid);
2655
perror_plus("fchown");
2663
/* Lower privileges */
2664
ret = lower_privileges();
2667
perror_plus("Failed to lower privileges");
2672
/* Remove invalid interface names (except "none") */
2674
char *interface = NULL;
2675
while((interface = argz_next(mc.interfaces, mc.interfaces_size,
2677
if(strcmp(interface, "none") != 0
2678
and if_nametoindex(interface) == 0){
2679
if(interface[0] != '\0'){
2680
fprintf_plus(stderr, "Not using nonexisting interface"
2681
" \"%s\"\n", interface);
2683
argz_delete(&mc.interfaces, &mc.interfaces_size, interface);
2689
/* Run network hooks */
2691
if(mc.interfaces != NULL){
2692
interfaces_hooks = malloc(mc.interfaces_size);
2693
if(interfaces_hooks == NULL){
2694
perror_plus("malloc");
997
/* sleep checking until interface is running */
998
for(int i=0; i < delay * 4; i++){
999
ret = ioctl(sd, SIOCGIFFLAGS, &network);
1001
perror("ioctl SIOCGIFFLAGS");
1002
} else if(network.ifr_flags & IFF_RUNNING){
2697
memcpy(interfaces_hooks, mc.interfaces, mc.interfaces_size);
2698
argz_stringify(interfaces_hooks, mc.interfaces_size, (int)',');
2700
run_network_hooks("start", interfaces_hooks != NULL ?
2701
interfaces_hooks : "", delay);
2705
avahi_set_log_function(empty_log);
2708
/* Initialize Avahi early so avahi_simple_poll_quit() can be called
2709
from the signal handler */
2710
/* Initialize the pseudo-RNG for Avahi */
2711
srand((unsigned int) time(NULL));
2712
simple_poll = avahi_simple_poll_new();
2713
if(simple_poll == NULL){
2714
fprintf_plus(stderr,
2715
"Avahi: Failed to create simple poll object.\n");
2716
exitcode = EX_UNAVAILABLE;
2720
sigemptyset(&sigterm_action.sa_mask);
2721
ret = sigaddset(&sigterm_action.sa_mask, SIGINT);
2723
perror_plus("sigaddset");
2724
exitcode = EX_OSERR;
2727
ret = sigaddset(&sigterm_action.sa_mask, SIGHUP);
2729
perror_plus("sigaddset");
2730
exitcode = EX_OSERR;
2733
ret = sigaddset(&sigterm_action.sa_mask, SIGTERM);
2735
perror_plus("sigaddset");
2736
exitcode = EX_OSERR;
2739
/* Need to check if the handler is SIG_IGN before handling:
2740
| [[info:libc:Initial Signal Actions]] |
2741
| [[info:libc:Basic Signal Handling]] |
2743
ret = sigaction(SIGINT, NULL, &old_sigterm_action);
2745
perror_plus("sigaction");
2748
if(old_sigterm_action.sa_handler != SIG_IGN){
2749
ret = sigaction(SIGINT, &sigterm_action, NULL);
2751
perror_plus("sigaction");
2752
exitcode = EX_OSERR;
2756
ret = sigaction(SIGHUP, NULL, &old_sigterm_action);
2758
perror_plus("sigaction");
2761
if(old_sigterm_action.sa_handler != SIG_IGN){
2762
ret = sigaction(SIGHUP, &sigterm_action, NULL);
2764
perror_plus("sigaction");
2765
exitcode = EX_OSERR;
2769
ret = sigaction(SIGTERM, NULL, &old_sigterm_action);
2771
perror_plus("sigaction");
2774
if(old_sigterm_action.sa_handler != SIG_IGN){
2775
ret = sigaction(SIGTERM, &sigterm_action, NULL);
2777
perror_plus("sigaction");
2778
exitcode = EX_OSERR;
2783
/* If no interfaces were specified, make a list */
2784
if(mc.interfaces == NULL){
2785
struct dirent **direntries = NULL;
2786
/* Look for any good interfaces */
2787
ret = scandir(sys_class_net, &direntries, good_interface,
2790
/* Add all found interfaces to interfaces list */
2791
for(int i = 0; i < ret; ++i){
2792
ret_errno = argz_add(&mc.interfaces, &mc.interfaces_size,
2793
direntries[i]->d_name);
2796
perror_plus("argz_add");
2797
free(direntries[i]);
2801
fprintf_plus(stderr, "Will use interface \"%s\"\n",
2802
direntries[i]->d_name);
2804
free(direntries[i]);
2811
fprintf_plus(stderr, "Could not find a network interface\n");
2812
exitcode = EXIT_FAILURE;
2817
/* Bring up interfaces which are down, and remove any "none"s */
2819
char *interface = NULL;
2820
while((interface = argz_next(mc.interfaces, mc.interfaces_size,
2822
/* If interface name is "none", stop bringing up interfaces.
2823
Also remove all instances of "none" from the list */
2824
if(strcmp(interface, "none") == 0){
2825
argz_delete(&mc.interfaces, &mc.interfaces_size,
2828
while((interface = argz_next(mc.interfaces,
2829
mc.interfaces_size, interface))){
2830
if(strcmp(interface, "none") == 0){
2831
argz_delete(&mc.interfaces, &mc.interfaces_size,
1005
struct timespec sleeptime = { .tv_nsec = 250000000 };
1006
ret = nanosleep(&sleeptime, NULL);
1007
if(ret == -1 and errno != EINTR){
1008
perror("nanosleep");
2838
bool interface_was_up = interface_is_up(interface);
2839
errno = bring_up_interface(interface, delay);
2840
if(not interface_was_up){
2842
fprintf_plus(stderr, "Failed to bring up interface \"%s\":"
2843
" %s\n", interface, strerror(errno));
2845
errno = argz_add(&interfaces_to_take_down,
2846
&interfaces_to_take_down_size,
2849
perror_plus("argz_add");
1011
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1016
/* Restores kernel loglevel to default */
1017
ret = klogctl(7, NULL, 0);
1037
ret = init_gnutls_global(&mc, pubkey, seckey);
1039
fprintf(stderr, "init_gnutls_global failed\n");
1040
exitcode = EXIT_FAILURE;
2854
if(debug and (interfaces_to_take_down == NULL)){
2855
fprintf_plus(stderr, "No interfaces were brought up\n");
2859
/* If we only got one interface, explicitly use only that one */
2860
if(argz_count(mc.interfaces, mc.interfaces_size) == 1){
2862
fprintf_plus(stderr, "Using only interface \"%s\"\n",
2865
if_index = (AvahiIfIndex)if_nametoindex(mc.interfaces);
2872
ret = init_gnutls_global(pubkey, seckey, dh_params_file, &mc);
2874
fprintf_plus(stderr, "init_gnutls_global failed\n");
2875
exitcode = EX_UNAVAILABLE;
1043
2878
gnutls_initialized = true;
1046
if(mkdtemp(tempdir) == NULL){
1050
tempdir_created = true;
1052
if(not init_gpgme(&mc, pubkey, seckey, tempdir)){
1053
fprintf(stderr, "init_gpgme failed\n");
1054
exitcode = EXIT_FAILURE;
2885
/* Try /run/tmp before /tmp */
2886
tempdir = mkdtemp(run_tempdir);
2887
if(tempdir == NULL and errno == ENOENT){
2889
fprintf_plus(stderr, "Tempdir %s did not work, trying %s\n",
2890
run_tempdir, old_tempdir);
2892
tempdir = mkdtemp(old_tempdir);
2894
if(tempdir == NULL){
2895
perror_plus("mkdtemp");
2903
if(not init_gpgme(pubkey, seckey, tempdir, &mc)){
2904
fprintf_plus(stderr, "init_gpgme failed\n");
2905
exitcode = EX_UNAVAILABLE;
1057
2908
gpgme_initialized = true;
1060
if_index = (AvahiIfIndex) if_nametoindex(interface);
1062
fprintf(stderr, "No such interface: \"%s\"\n", interface);
1063
exitcode = EXIT_FAILURE;
1179
3077
gpgme_release(mc.ctx);
1182
/* Removes the temp directory used by GPGME */
1183
if(tempdir_created){
1185
struct dirent *direntry;
1186
d = opendir(tempdir);
1188
if(errno != ENOENT){
1193
direntry = readdir(d);
1194
if(direntry == NULL){
1197
/* Skip "." and ".." */
1198
if(direntry->d_name[0] == '.'
1199
and (direntry->d_name[1] == '\0'
1200
or (direntry->d_name[1] == '.'
1201
and direntry->d_name[2] == '\0'))){
1204
char *fullname = NULL;
1205
ret = asprintf(&fullname, "%s/%s", tempdir,
1211
ret = remove(fullname);
1213
fprintf(stderr, "remove(\"%s\"): %s\n", fullname,
1220
ret = rmdir(tempdir);
1221
if(ret == -1 and errno != ENOENT){
3080
/* Cleans up the circular linked list of Mandos servers the client
3082
if(mc.current_server != NULL){
3083
mc.current_server->prev->next = NULL;
3084
while(mc.current_server != NULL){
3085
server *next = mc.current_server->next;
3087
#pragma GCC diagnostic push
3088
#pragma GCC diagnostic ignored "-Wcast-qual"
3090
free((char *)(mc.current_server->ip));
3092
#pragma GCC diagnostic pop
3094
free(mc.current_server);
3095
mc.current_server = next;
3099
/* Re-raise privileges */
3101
ret = raise_privileges();
3104
perror_plus("Failed to raise privileges");
3107
/* Run network hooks */
3108
run_network_hooks("stop", interfaces_hooks != NULL ?
3109
interfaces_hooks : "", delay);
3111
/* Take down the network interfaces which were brought up */
3113
char *interface = NULL;
3114
while((interface = argz_next(interfaces_to_take_down,
3115
interfaces_to_take_down_size,
3117
ret = take_down_interface(interface);
3120
perror_plus("Failed to take down interface");
3123
if(debug and (interfaces_to_take_down == NULL)){
3124
fprintf_plus(stderr, "No interfaces needed to be taken"
3130
ret = lower_privileges_permanently();
3133
perror_plus("Failed to lower privileges permanently");
3137
free(interfaces_to_take_down);
3138
free(interfaces_hooks);
3140
void clean_dir_at(int base, const char * const dirname,
3142
struct dirent **direntries = NULL;
3144
int dir_fd = (int)TEMP_FAILURE_RETRY(openat(base, dirname,
3150
perror_plus("open");
3153
int numentries = scandirat(dir_fd, ".", &direntries,
3154
notdotentries, alphasort);
3155
if(numentries >= 0){
3156
for(int i = 0; i < numentries; i++){
3158
fprintf_plus(stderr, "Unlinking \"%s/%s\"\n",
3159
dirname, direntries[i]->d_name);
3161
dret = unlinkat(dir_fd, direntries[i]->d_name, 0);
3163
if(errno == EISDIR){
3164
dret = unlinkat(dir_fd, direntries[i]->d_name,
3167
if((dret == -1) and (errno == ENOTEMPTY)
3168
and (strcmp(direntries[i]->d_name, "private-keys-v1.d")
3169
== 0) and (level == 0)){
3170
/* Recurse only in this special case */
3171
clean_dir_at(dir_fd, direntries[i]->d_name, level+1);
3174
if((dret == -1) and (errno != ENOENT)){
3175
fprintf_plus(stderr, "unlink(\"%s/%s\"): %s\n", dirname,
3176
direntries[i]->d_name, strerror(errno));
3179
free(direntries[i]);
3182
/* need to clean even if 0 because man page doesn't specify */
3184
dret = unlinkat(base, dirname, AT_REMOVEDIR);
3185
if(dret == -1 and errno != ENOENT){
3186
perror_plus("rmdir");
3189
perror_plus("scandirat");
3194
/* Removes the GPGME temp directory and all files inside */
3195
if(tempdir != NULL){
3196
clean_dir_at(-1, tempdir, 0);
3200
sigemptyset(&old_sigterm_action.sa_mask);
3201
old_sigterm_action.sa_handler = SIG_DFL;
3202
ret = (int)TEMP_FAILURE_RETRY(sigaction(signal_received,
3203
&old_sigterm_action,
3206
perror_plus("sigaction");
3209
ret = raise(signal_received);
3210
} while(ret != 0 and errno == EINTR);
3212
perror_plus("raise");
3215
TEMP_FAILURE_RETRY(pause());
1226
3218
return exitcode;