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
#ifndef _LARGEFILE_SOURCE
33
34
#define _LARGEFILE_SOURCE
36
#ifndef _FILE_OFFSET_BITS
34
37
#define _FILE_OFFSET_BITS 64
36
40
#define _GNU_SOURCE /* TEMP_FAILURE_RETRY(), asprintf() */
38
42
#include <stdio.h> /* fprintf(), stderr, fwrite(),
39
stdout, ferror(), sscanf(),
43
stdout, ferror(), remove() */
41
44
#include <stdint.h> /* uint16_t, uint32_t */
42
45
#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 <stdlib.h> /* free(), EXIT_SUCCESS, srand(),
48
#include <stdbool.h> /* bool, false, true */
46
49
#include <string.h> /* memset(), strcmp(), strlen(),
47
50
strerror(), asprintf(), strcpy() */
48
#include <sys/ioctl.h> /* ioctl */
51
#include <sys/ioctl.h> /* ioctl */
49
52
#include <sys/types.h> /* socket(), inet_pton(), sockaddr,
50
53
sockaddr_in6, PF_INET6,
51
SOCK_STREAM, INET6_ADDRSTRLEN,
52
uid_t, gid_t, open(), opendir(),
54
#include <sys/stat.h> /* open() */
54
SOCK_STREAM, uid_t, gid_t, open(),
56
#include <sys/stat.h> /* open(), S_ISREG */
55
57
#include <sys/socket.h> /* socket(), struct sockaddr_in6,
56
struct in6_addr, inet_pton(),
58
inet_pton(), connect() */
58
59
#include <fcntl.h> /* open() */
59
60
#include <dirent.h> /* opendir(), struct dirent, readdir()
61
#include <inttypes.h> /* PRIu16, intmax_t, SCNdMAX */
62
#include <inttypes.h> /* PRIu16, PRIdMAX, intmax_t,
62
64
#include <assert.h> /* assert() */
63
#include <errno.h> /* perror(), errno */
64
#include <time.h> /* nanosleep(), time() */
65
#include <errno.h> /* perror(), errno,
66
program_invocation_short_name */
67
#include <time.h> /* nanosleep(), time(), sleep() */
65
68
#include <net/if.h> /* ioctl, ifreq, SIOCGIFFLAGS, IFF_UP,
66
69
SIOCSIFFLAGS, if_indextoname(),
67
70
if_nametoindex(), IF_NAMESIZE */
68
#include <netinet/in.h>
71
#include <netinet/in.h> /* IN6_IS_ADDR_LINKLOCAL,
72
INET_ADDRSTRLEN, INET6_ADDRSTRLEN
69
74
#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 */
75
getuid(), getgid(), seteuid(),
77
#include <arpa/inet.h> /* inet_pton(), htons, inet_ntop() */
78
#include <iso646.h> /* not, or, and */
74
79
#include <argp.h> /* struct argp_option, error_t, struct
75
80
argp_state, struct argp,
76
81
argp_parse(), ARGP_KEY_ARG,
77
82
ARGP_KEY_END, ARGP_ERR_UNKNOWN */
83
#include <signal.h> /* sigemptyset(), sigaddset(),
84
sigaction(), SIGTERM, sig_atomic_t,
86
#include <sysexits.h> /* EX_OSERR, EX_USAGE, EX_UNAVAILABLE,
87
EX_NOHOST, EX_IOERR, EX_PROTOCOL */
88
#include <sys/wait.h> /* waitpid(), WIFEXITED(),
89
WEXITSTATUS(), WTERMSIG() */
79
92
#include <sys/klog.h> /* klogctl() */
93
#endif /* __linux__ */
83
96
/* All Avahi types, constants and functions
160
250
* Helper function to insert pub and seckey to the engine keyring.
162
252
bool import_key(const char *filename){
164
255
gpgme_data_t pgp_data;
166
257
fd = (int)TEMP_FAILURE_RETRY(open(filename, O_RDONLY));
172
263
rc = gpgme_data_new_from_fd(&pgp_data, fd);
173
264
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));
265
fprintf_plus(stderr, "bad gpgme_data_new_from_fd: %s: %s\n",
266
gpgme_strsource(rc), gpgme_strerror(rc));
179
rc = gpgme_op_import(mc->ctx, pgp_data);
270
rc = gpgme_op_import(mc.ctx, pgp_data);
180
271
if(rc != GPG_ERR_NO_ERROR){
181
fprintf(stderr, "bad gpgme_op_import: %s: %s\n",
182
gpgme_strsource(rc), gpgme_strerror(rc));
272
fprintf_plus(stderr, "bad gpgme_op_import: %s: %s\n",
273
gpgme_strsource(rc), gpgme_strerror(rc));
186
277
ret = (int)TEMP_FAILURE_RETRY(close(fd));
279
perror_plus("close");
190
281
gpgme_data_release(pgp_data);
195
fprintf(stderr, "Initialize gpgme\n");
286
fprintf_plus(stderr, "Initializing GPGME\n");
199
290
gpgme_check_version(NULL);
200
291
rc = gpgme_engine_check_version(GPGME_PROTOCOL_OpenPGP);
201
292
if(rc != GPG_ERR_NO_ERROR){
202
fprintf(stderr, "bad gpgme_engine_check_version: %s: %s\n",
203
gpgme_strsource(rc), gpgme_strerror(rc));
293
fprintf_plus(stderr, "bad gpgme_engine_check_version: %s: %s\n",
294
gpgme_strsource(rc), gpgme_strerror(rc));
207
/* Set GPGME home directory for the OpenPGP engine only */
298
/* Set GPGME home directory for the OpenPGP engine only */
208
299
rc = gpgme_get_engine_info(&engine_info);
209
300
if(rc != GPG_ERR_NO_ERROR){
210
fprintf(stderr, "bad gpgme_get_engine_info: %s: %s\n",
211
gpgme_strsource(rc), gpgme_strerror(rc));
301
fprintf_plus(stderr, "bad gpgme_get_engine_info: %s: %s\n",
302
gpgme_strsource(rc), gpgme_strerror(rc));
214
305
while(engine_info != NULL){
254
346
ssize_t plaintext_length = 0;
257
fprintf(stderr, "Trying to decrypt OpenPGP data\n");
349
fprintf_plus(stderr, "Trying to decrypt OpenPGP data\n");
260
352
/* Create new GPGME data buffer from memory cryptotext */
261
353
rc = gpgme_data_new_from_mem(&dh_crypto, cryptotext, crypto_size,
263
355
if(rc != GPG_ERR_NO_ERROR){
264
fprintf(stderr, "bad gpgme_data_new_from_mem: %s: %s\n",
265
gpgme_strsource(rc), gpgme_strerror(rc));
356
fprintf_plus(stderr, "bad gpgme_data_new_from_mem: %s: %s\n",
357
gpgme_strsource(rc), gpgme_strerror(rc));
269
361
/* Create new empty GPGME data buffer for the plaintext */
270
362
rc = gpgme_data_new(&dh_plain);
271
363
if(rc != GPG_ERR_NO_ERROR){
272
fprintf(stderr, "bad gpgme_data_new: %s: %s\n",
273
gpgme_strsource(rc), gpgme_strerror(rc));
364
fprintf_plus(stderr, "Mandos plugin mandos-client: "
365
"bad gpgme_data_new: %s: %s\n",
366
gpgme_strsource(rc), gpgme_strerror(rc));
274
367
gpgme_data_release(dh_crypto);
278
371
/* Decrypt data from the cryptotext data buffer to the plaintext
280
rc = gpgme_op_decrypt(mc->ctx, dh_crypto, dh_plain);
373
rc = gpgme_op_decrypt(mc.ctx, dh_crypto, dh_plain);
281
374
if(rc != GPG_ERR_NO_ERROR){
282
fprintf(stderr, "bad gpgme_op_decrypt: %s: %s\n",
283
gpgme_strsource(rc), gpgme_strerror(rc));
375
fprintf_plus(stderr, "bad gpgme_op_decrypt: %s: %s\n",
376
gpgme_strsource(rc), gpgme_strerror(rc));
284
377
plaintext_length = -1;
286
379
gpgme_decrypt_result_t result;
287
result = gpgme_op_decrypt_result(mc->ctx);
380
result = gpgme_op_decrypt_result(mc.ctx);
288
381
if(result == NULL){
289
fprintf(stderr, "gpgme_op_decrypt_result failed\n");
382
fprintf_plus(stderr, "gpgme_op_decrypt_result failed\n");
291
fprintf(stderr, "Unsupported algorithm: %s\n",
292
result->unsupported_algorithm);
293
fprintf(stderr, "Wrong key usage: %u\n",
294
result->wrong_key_usage);
384
fprintf_plus(stderr, "Unsupported algorithm: %s\n",
385
result->unsupported_algorithm);
386
fprintf_plus(stderr, "Wrong key usage: %u\n",
387
result->wrong_key_usage);
295
388
if(result->file_name != NULL){
296
fprintf(stderr, "File name: %s\n", result->file_name);
389
fprintf_plus(stderr, "File name: %s\n", result->file_name);
298
391
gpgme_recipient_t recipient;
299
392
recipient = result->recipients;
301
while(recipient != NULL){
302
fprintf(stderr, "Public key algorithm: %s\n",
303
gpgme_pubkey_algo_name(recipient->pubkey_algo));
304
fprintf(stderr, "Key ID: %s\n", recipient->keyid);
305
fprintf(stderr, "Secret key available: %s\n",
306
recipient->status == GPG_ERR_NO_SECKEY
308
recipient = recipient->next;
393
while(recipient != NULL){
394
fprintf_plus(stderr, "Public key algorithm: %s\n",
395
gpgme_pubkey_algo_name
396
(recipient->pubkey_algo));
397
fprintf_plus(stderr, "Key ID: %s\n", recipient->keyid);
398
fprintf_plus(stderr, "Secret key available: %s\n",
399
recipient->status == GPG_ERR_NO_SECKEY
401
recipient = recipient->next;
409
500
/* OpenPGP credentials */
410
gnutls_certificate_allocate_credentials(&mc->cred);
501
ret = gnutls_certificate_allocate_credentials(&mc.cred);
411
502
if(ret != GNUTLS_E_SUCCESS){
412
fprintf(stderr, "GnuTLS memory error: %s\n", /* Spurious warning
416
safer_gnutls_strerror(ret));
503
fprintf_plus(stderr, "GnuTLS memory error: %s\n",
504
safer_gnutls_strerror(ret));
417
505
gnutls_global_deinit();
422
fprintf(stderr, "Attempting to use OpenPGP public key %s and"
423
" secret key %s as GnuTLS credentials\n", pubkeyfilename,
510
fprintf_plus(stderr, "Attempting to use OpenPGP public key %s and"
511
" secret key %s as GnuTLS credentials\n",
427
516
ret = gnutls_certificate_set_openpgp_key_file
428
(mc->cred, pubkeyfilename, seckeyfilename,
517
(mc.cred, pubkeyfilename, seckeyfilename,
429
518
GNUTLS_OPENPGP_FMT_BASE64);
430
519
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));
521
"Error[%d] while reading the OpenPGP key pair ('%s',"
522
" '%s')\n", ret, pubkeyfilename, seckeyfilename);
523
fprintf_plus(stderr, "The GnuTLS error is: %s\n",
524
safer_gnutls_strerror(ret));
439
528
/* GnuTLS server initialization */
440
ret = gnutls_dh_params_init(&mc->dh_params);
529
ret = gnutls_dh_params_init(&mc.dh_params);
441
530
if(ret != GNUTLS_E_SUCCESS){
442
fprintf(stderr, "Error in GnuTLS DH parameter initialization:"
443
" %s\n", safer_gnutls_strerror(ret));
531
fprintf_plus(stderr, "Error in GnuTLS DH parameter"
532
" initialization: %s\n",
533
safer_gnutls_strerror(ret));
446
ret = gnutls_dh_params_generate2(mc->dh_params, mc->dh_bits);
536
ret = gnutls_dh_params_generate2(mc.dh_params, mc.dh_bits);
447
537
if(ret != GNUTLS_E_SUCCESS){
448
fprintf(stderr, "Error in GnuTLS prime generation: %s\n",
449
safer_gnutls_strerror(ret));
538
fprintf_plus(stderr, "Error in GnuTLS prime generation: %s\n",
539
safer_gnutls_strerror(ret));
453
gnutls_certificate_set_dh_params(mc->cred, mc->dh_params);
543
gnutls_certificate_set_dh_params(mc.cred, mc.dh_params);
459
gnutls_certificate_free_credentials(mc->cred);
549
gnutls_certificate_free_credentials(mc.cred);
460
550
gnutls_global_deinit();
461
gnutls_dh_params_deinit(mc->dh_params);
551
gnutls_dh_params_deinit(mc.dh_params);
465
static int init_gnutls_session(mandos_context *mc,
466
gnutls_session_t *session){
555
static int init_gnutls_session(gnutls_session_t *session){
468
557
/* GnuTLS session creation */
469
ret = gnutls_init(session, GNUTLS_SERVER);
559
ret = gnutls_init(session, GNUTLS_SERVER);
563
} while(ret == GNUTLS_E_INTERRUPTED or ret == GNUTLS_E_AGAIN);
470
564
if(ret != GNUTLS_E_SUCCESS){
471
fprintf(stderr, "Error in GnuTLS session initialization: %s\n",
472
safer_gnutls_strerror(ret));
566
"Error in GnuTLS session initialization: %s\n",
567
safer_gnutls_strerror(ret));
477
ret = gnutls_priority_set_direct(*session, mc->priority, &err);
573
ret = gnutls_priority_set_direct(*session, mc.priority, &err);
575
gnutls_deinit(*session);
578
} while(ret == GNUTLS_E_INTERRUPTED or ret == GNUTLS_E_AGAIN);
478
579
if(ret != GNUTLS_E_SUCCESS){
479
fprintf(stderr, "Syntax error at: %s\n", err);
480
fprintf(stderr, "GnuTLS error: %s\n",
481
safer_gnutls_strerror(ret));
580
fprintf_plus(stderr, "Syntax error at: %s\n", err);
581
fprintf_plus(stderr, "GnuTLS error: %s\n",
582
safer_gnutls_strerror(ret));
482
583
gnutls_deinit(*session);
487
ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,
589
ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,
592
gnutls_deinit(*session);
595
} while(ret == GNUTLS_E_INTERRUPTED or ret == GNUTLS_E_AGAIN);
489
596
if(ret != GNUTLS_E_SUCCESS){
490
fprintf(stderr, "Error setting GnuTLS credentials: %s\n",
491
safer_gnutls_strerror(ret));
597
fprintf_plus(stderr, "Error setting GnuTLS credentials: %s\n",
598
safer_gnutls_strerror(ret));
492
599
gnutls_deinit(*session);
496
603
/* ignore client certificate if any. */
497
gnutls_certificate_server_set_request(*session,
604
gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);
500
gnutls_dh_set_prime_bits(*session, mc->dh_bits);
606
gnutls_dh_set_prime_bits(*session, mc.dh_bits);
509
615
/* Called when a Mandos server is found */
510
616
static int start_mandos_communication(const char *ip, uint16_t port,
511
617
AvahiIfIndex if_index,
619
int ret, tcp_sd = -1;
515
union { struct sockaddr in; struct sockaddr_in6 in6; } to;
622
struct sockaddr_in in;
623
struct sockaddr_in6 in6;
516
625
char *buffer = NULL;
517
char *decrypted_buffer;
626
char *decrypted_buffer = NULL;
518
627
size_t buffer_length = 0;
519
628
size_t buffer_capacity = 0;
520
ssize_t decrypted_buffer_size;
523
char interface[IF_NAMESIZE];
524
631
gnutls_session_t session;
526
ret = init_gnutls_session(mc, &session);
632
int pf; /* Protocol family */
649
fprintf_plus(stderr, "Bad address family: %d\n", af);
654
ret = init_gnutls_session(&session);
532
fprintf(stderr, "Setting up a tcp connection to %s, port %" PRIu16
660
fprintf_plus(stderr, "Setting up a TCP connection to %s, port %"
661
PRIu16 "\n", ip, port);
536
tcp_sd = socket(PF_INET6, SOCK_STREAM, 0);
664
tcp_sd = socket(pf, SOCK_STREAM, 0);
667
perror_plus("socket");
543
if(if_indextoname((unsigned int)if_index, interface) == NULL){
544
perror("if_indextoname");
547
fprintf(stderr, "Binding to interface %s\n", interface);
550
677
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);
679
to.in6.sin6_family = (sa_family_t)af;
680
ret = inet_pton(af, ip, &to.in6.sin6_addr);
682
to.in.sin_family = (sa_family_t)af;
683
ret = inet_pton(af, ip, &to.in.sin_addr);
687
perror_plus("inet_pton");
560
fprintf(stderr, "Bad address: %s\n", ip);
693
fprintf_plus(stderr, "Bad address: %s\n", ip);
563
to.in6.sin6_port = htons(port); /* Spurious warnings from
698
to.in6.sin6_port = htons(port); /* Spurious warnings from
700
-Wunreachable-code */
702
if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */
703
(&to.in6.sin6_addr)){ /* -Wstrict-aliasing=2 or lower and
705
if(if_index == AVAHI_IF_UNSPEC){
706
fprintf_plus(stderr, "An IPv6 link-local address is"
707
" incomplete without a network interface\n");
711
/* Set the network interface number as scope */
712
to.in6.sin6_scope_id = (uint32_t)if_index;
715
to.in.sin_port = htons(port); /* Spurious warnings from
565
717
-Wunreachable-code */
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){
726
if(af == AF_INET6 and if_index != AVAHI_IF_UNSPEC){
727
char interface[IF_NAMESIZE];
728
if(if_indextoname((unsigned int)if_index, interface) == NULL){
729
perror_plus("if_indextoname");
731
fprintf_plus(stderr, "Connection to: %s%%%s, port %" PRIu16
732
"\n", ip, interface, port);
735
fprintf_plus(stderr, "Connection to: %s, port %" PRIu16 "\n",
738
char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?
739
INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";
742
pcret = inet_ntop(af, &(to.in6.sin6_addr), addrstr,
745
pcret = inet_ntop(af, &(to.in.sin_addr), addrstr,
749
perror_plus("inet_ntop");
577
751
if(strcmp(addrstr, ip) != 0){
578
fprintf(stderr, "Canonical address form: %s\n", addrstr);
752
fprintf_plus(stderr, "Canonical address form: %s\n", addrstr);
583
ret = connect(tcp_sd, &to.in, sizeof(to));
763
ret = connect(tcp_sd, &to.in6, sizeof(to));
765
ret = connect(tcp_sd, &to.in, sizeof(to)); /* IPv4 */
768
if ((errno != ECONNREFUSED and errno != ENETUNREACH) or debug){
770
perror_plus("connect");
589
781
const char *out = mandos_protocol_version;
815
1085
case AVAHI_BROWSER_ALL_FOR_NOW:
816
1086
case AVAHI_BROWSER_CACHE_EXHAUSTED:
818
fprintf(stderr, "No Mandos server found, still searching...\n");
1088
fprintf_plus(stderr, "No Mandos server found, still"
1095
/* Signal handler that stops main loop after SIGTERM */
1096
static void handle_sigterm(int sig){
1101
signal_received = sig;
1102
int old_errno = errno;
1103
/* set main loop to exit */
1104
if(mc.simple_poll != NULL){
1105
avahi_simple_poll_quit(mc.simple_poll);
1110
bool get_flags(const char *ifname, struct ifreq *ifr){
1113
int s = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1115
perror_plus("socket");
1118
strcpy(ifr->ifr_name, ifname);
1119
ret = ioctl(s, SIOCGIFFLAGS, ifr);
1122
perror_plus("ioctl SIOCGIFFLAGS");
1129
bool good_flags(const char *ifname, const struct ifreq *ifr){
1131
/* Reject the loopback device */
1132
if(ifr->ifr_flags & IFF_LOOPBACK){
1134
fprintf_plus(stderr, "Rejecting loopback interface \"%s\"\n",
1139
/* Accept point-to-point devices only if connect_to is specified */
1140
if(connect_to != NULL and (ifr->ifr_flags & IFF_POINTOPOINT)){
1142
fprintf_plus(stderr, "Accepting point-to-point interface"
1143
" \"%s\"\n", ifname);
1147
/* Otherwise, reject non-broadcast-capable devices */
1148
if(not (ifr->ifr_flags & IFF_BROADCAST)){
1150
fprintf_plus(stderr, "Rejecting non-broadcast interface"
1151
" \"%s\"\n", ifname);
1155
/* Reject non-ARP interfaces (including dummy interfaces) */
1156
if(ifr->ifr_flags & IFF_NOARP){
1158
fprintf_plus(stderr, "Rejecting non-ARP interface \"%s\"\n",
1164
/* Accept this device */
1166
fprintf_plus(stderr, "Interface \"%s\" is good\n", ifname);
1172
* This function determines if a directory entry in /sys/class/net
1173
* corresponds to an acceptable network device.
1174
* (This function is passed to scandir(3) as a filter function.)
1176
int good_interface(const struct dirent *if_entry){
1177
if(if_entry->d_name[0] == '.'){
1182
if(not get_flags(if_entry->d_name, &ifr)){
1184
fprintf_plus(stderr, "Failed to get flags for interface "
1185
"\"%s\"\n", if_entry->d_name);
1190
if(not good_flags(if_entry->d_name, &ifr)){
1197
* This function determines if a directory entry in /sys/class/net
1198
* corresponds to an acceptable network device which is up.
1199
* (This function is passed to scandir(3) as a filter function.)
1201
int up_interface(const struct dirent *if_entry){
1202
if(if_entry->d_name[0] == '.'){
1207
if(not get_flags(if_entry->d_name, &ifr)){
1209
fprintf_plus(stderr, "Failed to get flags for interface "
1210
"\"%s\"\n", if_entry->d_name);
1215
/* Reject down interfaces */
1216
if(not (ifr.ifr_flags & IFF_UP)){
1218
fprintf_plus(stderr, "Rejecting down interface \"%s\"\n",
1224
/* Reject non-running interfaces */
1225
if(not (ifr.ifr_flags & IFF_RUNNING)){
1227
fprintf_plus(stderr, "Rejecting non-running interface \"%s\"\n",
1233
if(not good_flags(if_entry->d_name, &ifr)){
1239
int notdotentries(const struct dirent *direntry){
1240
/* Skip "." and ".." */
1241
if(direntry->d_name[0] == '.'
1242
and (direntry->d_name[1] == '\0'
1243
or (direntry->d_name[1] == '.'
1244
and direntry->d_name[2] == '\0'))){
1250
/* Is this directory entry a runnable program? */
1251
int runnable_hook(const struct dirent *direntry){
1256
if((direntry->d_name)[0] == '\0'){
1261
sret = strspn(direntry->d_name, "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
1262
"abcdefghijklmnopqrstuvwxyz"
1265
if((direntry->d_name)[sret] != '\0'){
1266
/* Contains non-allowed characters */
1268
fprintf_plus(stderr, "Ignoring hook \"%s\" with bad name\n",
1274
char *fullname = NULL;
1275
ret = asprintf(&fullname, "%s/%s", hookdir, direntry->d_name);
1277
perror_plus("asprintf");
1281
ret = stat(fullname, &st);
1284
perror_plus("Could not stat hook");
1288
if(not (S_ISREG(st.st_mode))){
1289
/* Not a regular file */
1291
fprintf_plus(stderr, "Ignoring hook \"%s\" - not a file\n",
1296
if(not (st.st_mode & (S_IXUSR | S_IXGRP | S_IXOTH))){
1297
/* Not executable */
1299
fprintf_plus(stderr, "Ignoring hook \"%s\" - not executable\n",
1305
fprintf_plus(stderr, "Hook \"%s\" is acceptable\n",
1311
int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval){
1313
struct timespec now;
1314
struct timespec waited_time;
1315
intmax_t block_time;
1318
if(mc.current_server == NULL){
1320
fprintf_plus(stderr, "Wait until first server is found."
1323
ret = avahi_simple_poll_iterate(s, -1);
1326
fprintf_plus(stderr, "Check current_server if we should run"
1329
/* the current time */
1330
ret = clock_gettime(CLOCK_MONOTONIC, &now);
1332
perror_plus("clock_gettime");
1335
/* Calculating in ms how long time between now and server
1336
who we visted longest time ago. Now - last seen. */
1337
waited_time.tv_sec = (now.tv_sec
1338
- mc.current_server->last_seen.tv_sec);
1339
waited_time.tv_nsec = (now.tv_nsec
1340
- mc.current_server->last_seen.tv_nsec);
1341
/* total time is 10s/10,000ms.
1342
Converting to s from ms by dividing by 1,000,
1343
and ns to ms by dividing by 1,000,000. */
1344
block_time = ((retry_interval
1345
- ((intmax_t)waited_time.tv_sec * 1000))
1346
- ((intmax_t)waited_time.tv_nsec / 1000000));
1349
fprintf_plus(stderr, "Blocking for %" PRIdMAX " ms\n",
1353
if(block_time <= 0){
1354
ret = start_mandos_communication(mc.current_server->ip,
1355
mc.current_server->port,
1356
mc.current_server->if_index,
1357
mc.current_server->af);
1359
avahi_simple_poll_quit(mc.simple_poll);
1362
ret = clock_gettime(CLOCK_MONOTONIC,
1363
&mc.current_server->last_seen);
1365
perror_plus("clock_gettime");
1368
mc.current_server = mc.current_server->next;
1369
block_time = 0; /* Call avahi to find new Mandos
1370
servers, but don't block */
1373
ret = avahi_simple_poll_iterate(s, (int)block_time);
1376
if (ret > 0 or errno != EINTR){
1377
return (ret != 1) ? ret : 0;
1383
bool run_network_hooks(const char *mode, const char *interface,
1385
struct dirent **direntries;
1386
struct dirent *direntry;
1388
int numhooks = scandir(hookdir, &direntries, runnable_hook,
1391
perror_plus("scandir");
1393
int devnull = open("/dev/null", O_RDONLY);
1394
for(int i = 0; i < numhooks; i++){
1395
direntry = direntries[i];
1396
char *fullname = NULL;
1397
ret = asprintf(&fullname, "%s/%s", hookdir, direntry->d_name);
1399
perror_plus("asprintf");
1403
fprintf_plus(stderr, "Running network hook \"%s\"\n",
1406
pid_t hook_pid = fork();
1409
dup2(devnull, STDIN_FILENO);
1411
dup2(STDERR_FILENO, STDOUT_FILENO);
1412
ret = setenv("MANDOSNETHOOKDIR", hookdir, 1);
1414
perror_plus("setenv");
1417
ret = setenv("DEVICE", interface, 1);
1419
perror_plus("setenv");
1422
ret = setenv("VERBOSE", debug ? "1" : "0", 1);
1424
perror_plus("setenv");
1427
ret = setenv("MODE", mode, 1);
1429
perror_plus("setenv");
1433
ret = asprintf(&delaystring, "%f", delay);
1435
perror_plus("asprintf");
1438
ret = setenv("DELAY", delaystring, 1);
1441
perror_plus("setenv");
1445
ret = execl(fullname, direntry->d_name, mode, NULL);
1446
perror_plus("execl");
1449
if(TEMP_FAILURE_RETRY(waitpid(hook_pid, &status, 0)) == -1){
1450
perror_plus("waitpid");
1454
if(WIFEXITED(status)){
1455
if(WEXITSTATUS(status) != 0){
1456
fprintf_plus(stderr, "Warning: network hook \"%s\" exited"
1457
" with status %d\n", direntry->d_name,
1458
WEXITSTATUS(status));
1462
} else if(WIFSIGNALED(status)){
1463
fprintf_plus(stderr, "Warning: network hook \"%s\" died by"
1464
" signal %d\n", direntry->d_name,
1469
fprintf_plus(stderr, "Warning: network hook \"%s\""
1470
" crashed\n", direntry->d_name);
1477
fprintf_plus(stderr, "Network hook \"%s\" ran successfully\n",
824
1486
int main(int argc, char *argv[]){
825
1487
AvahiSServiceBrowser *sb = NULL;
828
1490
intmax_t tmpmax;
830
1492
int exitcode = EXIT_SUCCESS;
831
const char *interface = "eth0";
1493
const char *interface = "";
832
1494
struct ifreq network;
1496
bool take_down_interface = false;
836
char *connect_to = NULL;
837
1499
char tempdir[] = "/tmp/mandosXXXXXX";
838
1500
bool tempdir_created = false;
839
1501
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
840
1502
const char *seckey = PATHDIR "/" SECKEY;
841
1503
const char *pubkey = PATHDIR "/" PUBKEY;
843
mandos_context mc = { .simple_poll = NULL, .server = NULL,
844
.dh_bits = 1024, .priority = "SECURE256"
845
":!CTYPE-X.509:+CTYPE-OPENPGP" };
846
1505
bool gnutls_initialized = false;
847
1506
bool gpgme_initialized = false;
1508
double retry_interval = 10; /* 10s between trying a server and
1509
retrying the same server again */
1511
struct sigaction old_sigterm_action = { .sa_handler = SIG_DFL };
1512
struct sigaction sigterm_action = { .sa_handler = handle_sigterm };
1517
/* Lower any group privileges we might have, just to be safe */
1521
perror_plus("setgid");
1524
/* Lower user privileges (temporarily) */
1528
perror_plus("seteuid");
851
1536
struct argp_option options[] = {
915
1618
mc.priority = arg;
917
1620
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");
1622
delay = strtof(arg, &tmp);
1623
if(errno != 0 or tmp == arg or *tmp != '\0'){
1624
argp_error(state, "Bad delay");
1626
case 132: /* --retry */
1628
retry_interval = strtod(arg, &tmp);
1629
if(errno != 0 or tmp == arg or *tmp != '\0'
1630
or (retry_interval * 1000) > INT_MAX
1631
or retry_interval < 0){
1632
argp_error(state, "Bad retry interval");
1635
case 133: /* --network-hook-dir */
1639
* These reproduce what we would get without ARGP_NO_HELP
1641
case '?': /* --help */
1642
argp_state_help(state, state->out_stream,
1643
(ARGP_HELP_STD_HELP | ARGP_HELP_EXIT_ERR)
1644
& ~(unsigned int)ARGP_HELP_EXIT_OK);
1645
case -3: /* --usage */
1646
argp_state_help(state, state->out_stream,
1647
ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);
1648
case 'V': /* --version */
1649
fprintf_plus(state->out_stream,
1650
"Mandos plugin mandos-client: ");
1651
fprintf_plus(state->out_stream, "%s\n", argp_program_version);
1652
exit(argp_err_exit_status);
929
1655
return ARGP_ERR_UNKNOWN;
934
1660
struct argp argp = { .options = options, .parser = parse_opt,
936
1662
.doc = "Mandos client -- Get and decrypt"
937
1663
" 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");
1664
ret = argp_parse(&argp, argc, argv,
1665
ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);
1672
perror_plus("argp_parse");
1673
exitcode = EX_OSERR;
1676
exitcode = EX_USAGE;
1682
/* Work around Debian bug #633582:
1683
<http://bugs.debian.org/633582> */
1686
/* Re-raise priviliges */
1690
perror_plus("seteuid");
1693
if(strcmp(seckey, PATHDIR "/" SECKEY) == 0){
1694
int seckey_fd = open(seckey, O_RDONLY);
1695
if(seckey_fd == -1){
1696
perror_plus("open");
1698
ret = (int)TEMP_FAILURE_RETRY(fstat(seckey_fd, &st));
1700
perror_plus("fstat");
1702
if(S_ISREG(st.st_mode)
1703
and st.st_uid == 0 and st.st_gid == 0){
1704
ret = fchown(seckey_fd, uid, gid);
1706
perror_plus("fchown");
1710
TEMP_FAILURE_RETRY(close(seckey_fd));
1714
if(strcmp(pubkey, PATHDIR "/" PUBKEY) == 0){
1715
int pubkey_fd = open(pubkey, O_RDONLY);
1716
if(pubkey_fd == -1){
1717
perror_plus("open");
1719
ret = (int)TEMP_FAILURE_RETRY(fstat(pubkey_fd, &st));
1721
perror_plus("fstat");
1723
if(S_ISREG(st.st_mode)
1724
and st.st_uid == 0 and st.st_gid == 0){
1725
ret = fchown(pubkey_fd, uid, gid);
1727
perror_plus("fchown");
1731
TEMP_FAILURE_RETRY(close(pubkey_fd));
1735
/* Lower privileges */
1739
perror_plus("seteuid");
1743
/* Run network hooks */
1746
/* Re-raise priviliges */
1750
perror_plus("seteuid");
1753
if(not run_network_hooks("start", interface, delay)){
1757
/* Lower privileges */
1761
perror_plus("seteuid");
1767
avahi_set_log_function(empty_log);
1770
if(interface[0] == '\0'){
1771
struct dirent **direntries;
1772
/* First look for interfaces that are up */
1773
ret = scandir(sys_class_net, &direntries, up_interface,
1776
/* No up interfaces, look for any good interfaces */
1778
ret = scandir(sys_class_net, &direntries, good_interface,
1782
/* Pick the first interface returned */
1783
interface = strdup(direntries[0]->d_name);
1785
fprintf_plus(stderr, "Using interface \"%s\"\n", interface);
1787
if(interface == NULL){
1788
perror_plus("malloc");
1790
exitcode = EXIT_FAILURE;
1796
fprintf_plus(stderr, "Could not find a network interface\n");
941
1797
exitcode = EXIT_FAILURE;
1802
/* Initialize Avahi early so avahi_simple_poll_quit() can be called
1803
from the signal handler */
1804
/* Initialize the pseudo-RNG for Avahi */
1805
srand((unsigned int) time(NULL));
1806
mc.simple_poll = avahi_simple_poll_new();
1807
if(mc.simple_poll == NULL){
1808
fprintf_plus(stderr,
1809
"Avahi: Failed to create simple poll object.\n");
1810
exitcode = EX_UNAVAILABLE;
1814
sigemptyset(&sigterm_action.sa_mask);
1815
ret = sigaddset(&sigterm_action.sa_mask, SIGINT);
1817
perror_plus("sigaddset");
1818
exitcode = EX_OSERR;
1821
ret = sigaddset(&sigterm_action.sa_mask, SIGHUP);
1823
perror_plus("sigaddset");
1824
exitcode = EX_OSERR;
1827
ret = sigaddset(&sigterm_action.sa_mask, SIGTERM);
1829
perror_plus("sigaddset");
1830
exitcode = EX_OSERR;
1833
/* Need to check if the handler is SIG_IGN before handling:
1834
| [[info:libc:Initial Signal Actions]] |
1835
| [[info:libc:Basic Signal Handling]] |
1837
ret = sigaction(SIGINT, NULL, &old_sigterm_action);
1839
perror_plus("sigaction");
1842
if(old_sigterm_action.sa_handler != SIG_IGN){
1843
ret = sigaction(SIGINT, &sigterm_action, NULL);
1845
perror_plus("sigaction");
1846
exitcode = EX_OSERR;
1850
ret = sigaction(SIGHUP, NULL, &old_sigterm_action);
1852
perror_plus("sigaction");
1855
if(old_sigterm_action.sa_handler != SIG_IGN){
1856
ret = sigaction(SIGHUP, &sigterm_action, NULL);
1858
perror_plus("sigaction");
1859
exitcode = EX_OSERR;
1863
ret = sigaction(SIGTERM, NULL, &old_sigterm_action);
1865
perror_plus("sigaction");
1868
if(old_sigterm_action.sa_handler != SIG_IGN){
1869
ret = sigaction(SIGTERM, &sigterm_action, NULL);
1871
perror_plus("sigaction");
1872
exitcode = EX_OSERR;
946
1877
/* If the interface is down, bring it up */
1878
if(strcmp(interface, "none") != 0){
1879
if_index = (AvahiIfIndex) if_nametoindex(interface);
1881
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
1882
exitcode = EX_UNAVAILABLE;
1890
/* Re-raise priviliges */
1894
perror_plus("seteuid");
948
1897
#ifdef __linux__
949
1898
/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO
950
messages to mess up the prompt */
1899
messages about the network interface to mess up the prompt */
951
1900
ret = klogctl(8, NULL, 5);
1901
bool restore_loglevel = true;
1903
restore_loglevel = false;
1904
perror_plus("klogctl");
1906
#endif /* __linux__ */
957
1908
sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
960
exitcode = EXIT_FAILURE;
1910
perror_plus("socket");
1911
exitcode = EX_OSERR;
961
1912
#ifdef __linux__
962
ret = klogctl(7, NULL, 0);
1913
if(restore_loglevel){
1914
ret = klogctl(7, NULL, 0);
1916
perror_plus("klogctl");
1919
#endif /* __linux__ */
1920
/* Lower privileges */
1924
perror_plus("seteuid");
969
1928
strcpy(network.ifr_name, interface);
970
1929
ret = ioctl(sd, SIOCGIFFLAGS, &network);
972
perror("ioctl SIOCGIFFLAGS");
1931
perror_plus("ioctl SIOCGIFFLAGS");
973
1932
#ifdef __linux__
974
ret = klogctl(7, NULL, 0);
1933
if(restore_loglevel){
1934
ret = klogctl(7, NULL, 0);
1936
perror_plus("klogctl");
1939
#endif /* __linux__ */
1940
exitcode = EX_OSERR;
1941
/* Lower privileges */
1945
perror_plus("seteuid");
979
exitcode = EXIT_FAILURE;
982
1949
if((network.ifr_flags & IFF_UP) == 0){
983
1950
network.ifr_flags |= IFF_UP;
1951
take_down_interface = true;
984
1952
ret = ioctl(sd, SIOCSIFFLAGS, &network);
986
perror("ioctl SIOCSIFFLAGS");
987
exitcode = EXIT_FAILURE;
1954
take_down_interface = false;
1955
perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");
1956
exitcode = EX_OSERR;
988
1957
#ifdef __linux__
989
ret = klogctl(7, NULL, 0);
1958
if(restore_loglevel){
1959
ret = klogctl(7, NULL, 0);
1961
perror_plus("klogctl");
1964
#endif /* __linux__ */
1965
/* Lower privileges */
1969
perror_plus("seteuid");
997
/* sleep checking until interface is running */
1974
/* Sleep checking until interface is running.
1975
Check every 0.25s, up to total time of delay */
998
1976
for(int i=0; i < delay * 4; i++){
999
1977
ret = ioctl(sd, SIOCGIFFLAGS, &network);
1001
perror("ioctl SIOCGIFFLAGS");
1979
perror_plus("ioctl SIOCGIFFLAGS");
1002
1980
} else if(network.ifr_flags & IFF_RUNNING){
1005
1983
struct timespec sleeptime = { .tv_nsec = 250000000 };
1006
1984
ret = nanosleep(&sleeptime, NULL);
1007
1985
if(ret == -1 and errno != EINTR){
1008
perror("nanosleep");
1986
perror_plus("nanosleep");
1011
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1989
if(not take_down_interface){
1990
/* We won't need the socket anymore */
1991
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1993
perror_plus("close");
1015
1996
#ifdef __linux__
1016
/* Restores kernel loglevel to default */
1017
ret = klogctl(7, NULL, 0);
1997
if(restore_loglevel){
1998
/* Restores kernel loglevel to default */
1999
ret = klogctl(7, NULL, 0);
2001
perror_plus("klogctl");
2004
#endif /* __linux__ */
2005
/* Lower privileges */
2007
/* Lower privileges */
2010
perror_plus("seteuid");
1037
ret = init_gnutls_global(&mc, pubkey, seckey);
1039
fprintf(stderr, "init_gnutls_global failed\n");
1040
exitcode = EXIT_FAILURE;
2018
ret = init_gnutls_global(pubkey, seckey);
2020
fprintf_plus(stderr, "init_gnutls_global failed\n");
2021
exitcode = EX_UNAVAILABLE;
1043
2024
gnutls_initialized = true;
1046
2031
if(mkdtemp(tempdir) == NULL){
2032
perror_plus("mkdtemp");
1050
2035
tempdir_created = true;
1052
if(not init_gpgme(&mc, pubkey, seckey, tempdir)){
1053
fprintf(stderr, "init_gpgme failed\n");
1054
exitcode = EXIT_FAILURE;
2041
if(not init_gpgme(pubkey, seckey, tempdir)){
2042
fprintf_plus(stderr, "init_gpgme failed\n");
2043
exitcode = EX_UNAVAILABLE;
1057
2046
gpgme_initialized = true;
1060
if_index = (AvahiIfIndex) if_nametoindex(interface);
1062
fprintf(stderr, "No such interface: \"%s\"\n", interface);
1063
exitcode = EXIT_FAILURE;
1179
2206
gpgme_release(mc.ctx);
1182
/* Removes the temp directory used by GPGME */
2209
/* Cleans up the circular linked list of Mandos servers the client
2211
if(mc.current_server != NULL){
2212
mc.current_server->prev->next = NULL;
2213
while(mc.current_server != NULL){
2214
server *next = mc.current_server->next;
2215
free(mc.current_server);
2216
mc.current_server = next;
2220
/* Re-raise priviliges */
2226
perror_plus("seteuid");
2230
/* Run network hooks */
2231
run_network_hooks("stop", interface, delay);
2233
/* Take down the network interface */
2234
if(take_down_interface and geteuid() == 0){
2235
ret = ioctl(sd, SIOCGIFFLAGS, &network);
2237
perror_plus("ioctl SIOCGIFFLAGS");
2238
} else if(network.ifr_flags & IFF_UP){
2239
network.ifr_flags &= ~(short)IFF_UP; /* clear flag */
2240
ret = ioctl(sd, SIOCSIFFLAGS, &network);
2242
perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");
2245
ret = (int)TEMP_FAILURE_RETRY(close(sd));
2247
perror_plus("close");
2252
/* Lower privileges permanently */
2256
perror_plus("setuid");
2260
/* Removes the GPGME temp directory and all files inside */
1183
2261
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'))){
2262
struct dirent **direntries = NULL;
2263
struct dirent *direntry = NULL;
2264
int numentries = scandir(tempdir, &direntries, notdotentries,
2266
if (numentries > 0){
2267
for(int i = 0; i < numentries; i++){
2268
direntry = direntries[i];
1204
2269
char *fullname = NULL;
1205
2270
ret = asprintf(&fullname, "%s/%s", tempdir,
1206
2271
direntry->d_name);
2273
perror_plus("asprintf");
1211
2276
ret = remove(fullname);
1213
fprintf(stderr, "remove(\"%s\"): %s\n", fullname,
2278
fprintf_plus(stderr, "remove(\"%s\"): %s\n", fullname,
1216
2281
free(fullname);
2285
/* need to clean even if 0 because man page doesn't specify */
2287
if (numentries == -1){
2288
perror_plus("scandir");
1220
2290
ret = rmdir(tempdir);
1221
2291
if(ret == -1 and errno != ENOENT){
2292
perror_plus("rmdir");
2297
sigemptyset(&old_sigterm_action.sa_mask);
2298
old_sigterm_action.sa_handler = SIG_DFL;
2299
ret = (int)TEMP_FAILURE_RETRY(sigaction(signal_received,
2300
&old_sigterm_action,
2303
perror_plus("sigaction");
2306
ret = raise(signal_received);
2307
} while(ret != 0 and errno == EINTR);
2309
perror_plus("raise");
2312
TEMP_FAILURE_RETRY(pause());
1226
2315
return exitcode;