102
137
#define BUFFER_SIZE 256
105
#define PATHDIR "/conf/conf.d/mandos"
108
139
#define PATHDIR "/conf/conf.d/mandos"
109
140
#define SECKEY "seckey.txt"
110
#define PUBKEY "pupkey.txt"
141
#define PUBKEY "pubkey.txt"
142
#define HOOKDIR "/lib/mandos/network-hooks.d"
112
144
bool debug = false;
113
145
static const char mandos_protocol_version[] = "1";
114
const char *argp_program_version = "password-request 1.0";
115
const char *argp_program_bug_address = "<mandos@fukt.bsnet.se>";
146
const char *argp_program_version = "mandos-client " VERSION;
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;
117
166
/* Used for passing in values through the Avahi callback functions */
119
AvahiSimplePoll *simple_poll;
120
168
AvahiServer *server;
121
169
gnutls_certificate_credentials_t cred;
122
170
unsigned int dh_bits;
123
171
gnutls_dh_params_t dh_params;
124
172
const char *priority;
174
server *current_server;
176
size_t interfaces_size;
126
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));
129
* Make room in "buffer" for at least BUFFER_SIZE additional bytes.
130
* "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,
131
207
* "buffer_length" is how much is already used.
133
size_t adjustbuffer(char **buffer, size_t buffer_length,
134
size_t buffer_capacity){
135
if (buffer_length + BUFFER_SIZE > buffer_capacity){
136
*buffer = realloc(*buffer, buffer_capacity + BUFFER_SIZE);
209
__attribute__((nonnull, warn_unused_result))
210
size_t incbuffer(char **buffer, size_t buffer_length,
211
size_t buffer_capacity){
212
if(buffer_length + BUFFER_SIZE > buffer_capacity){
213
char *new_buf = realloc(*buffer, buffer_capacity + BUFFER_SIZE);
215
int old_errno = errno;
140
222
buffer_capacity += BUFFER_SIZE;
142
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;
275
/* Set effective uid to 0, return errno */
276
__attribute__((warn_unused_result))
277
int raise_privileges(void){
278
int old_errno = errno;
280
if(seteuid(0) == -1){
287
/* Set effective and real user ID to 0. Return errno. */
288
__attribute__((warn_unused_result))
289
int raise_privileges_permanently(void){
290
int old_errno = errno;
291
int ret = raise_privileges();
303
/* Set effective user ID to unprivileged saved user ID */
304
__attribute__((warn_unused_result))
305
int lower_privileges(void){
306
int old_errno = errno;
308
if(seteuid(uid) == -1){
315
/* Lower privileges permanently */
316
__attribute__((warn_unused_result))
317
int lower_privileges_permanently(void){
318
int old_errno = errno;
320
if(setuid(uid) == -1){
146
328
* Initialize GPGME.
148
static bool init_gpgme(mandos_context *mc, const char *seckey,
149
const char *pubkey, const char *tempdir){
330
__attribute__((nonnull, warn_unused_result))
331
static bool init_gpgme(const char * const seckey,
332
const char * const pubkey,
333
const char * const tempdir,
151
335
gpgme_error_t rc;
152
336
gpgme_engine_info_t engine_info;
156
* Helper function to insert pub and seckey to the enigne keyring.
339
* Helper function to insert pub and seckey to the engine keyring.
158
bool import_key(const char *filename){
341
bool import_key(const char * const filename){
160
344
gpgme_data_t pgp_data;
162
fd = TEMP_FAILURE_RETRY(open(filename, O_RDONLY));
346
fd = (int)TEMP_FAILURE_RETRY(open(filename, O_RDONLY));
352
/* Workaround for systems without a real-time clock; see also
353
Debian bug #894495: <https://bugs.debian.org/894495> */
356
time_t currtime = time(NULL);
357
if(currtime != (time_t)-1){
359
if(gmtime_r(&currtime, &tm) == NULL) {
360
perror_plus("gmtime_r");
363
if(tm.tm_year != 70 or tm.tm_mon != 0){
367
fprintf_plus(stderr, "System clock is January 1970");
371
fprintf_plus(stderr, "System clock is invalid");
376
ret = fstat(fd, &keystat);
378
perror_plus("fstat");
381
ret = raise_privileges();
384
perror_plus("Failed to raise privileges");
389
"Setting system clock to key file mtime");
391
time_t keytime = keystat.st_mtim.tv_sec;
392
if(stime(&keytime) != 0){
393
perror_plus("stime");
395
ret = lower_privileges();
398
perror_plus("Failed to lower privileges");
168
402
rc = gpgme_data_new_from_fd(&pgp_data, fd);
169
if (rc != GPG_ERR_NO_ERROR){
170
fprintf(stderr, "bad gpgme_data_new_from_fd: %s: %s\n",
171
gpgme_strsource(rc), gpgme_strerror(rc));
403
if(rc != GPG_ERR_NO_ERROR){
404
fprintf_plus(stderr, "bad gpgme_data_new_from_fd: %s: %s\n",
405
gpgme_strsource(rc), gpgme_strerror(rc));
175
409
rc = gpgme_op_import(mc->ctx, pgp_data);
176
if (rc != GPG_ERR_NO_ERROR){
177
fprintf(stderr, "bad gpgme_op_import: %s: %s\n",
178
gpgme_strsource(rc), gpgme_strerror(rc));
410
if(rc != GPG_ERR_NO_ERROR){
411
fprintf_plus(stderr, "bad gpgme_op_import: %s: %s\n",
412
gpgme_strsource(rc), gpgme_strerror(rc));
182
ret = TEMP_FAILURE_RETRY(close(fd));
416
gpgme_import_result_t import_result
417
= gpgme_op_import_result(mc->ctx);
418
if((import_result->imported < 1
419
or import_result->not_imported > 0)
420
and import_result->unchanged == 0){
421
fprintf_plus(stderr, "bad gpgme_op_import_results:\n");
423
"The total number of considered keys: %d\n",
424
import_result->considered);
426
"The number of keys without user ID: %d\n",
427
import_result->no_user_id);
429
"The total number of imported keys: %d\n",
430
import_result->imported);
431
fprintf_plus(stderr, "The number of imported RSA keys: %d\n",
432
import_result->imported_rsa);
433
fprintf_plus(stderr, "The number of unchanged keys: %d\n",
434
import_result->unchanged);
435
fprintf_plus(stderr, "The number of new user IDs: %d\n",
436
import_result->new_user_ids);
437
fprintf_plus(stderr, "The number of new sub keys: %d\n",
438
import_result->new_sub_keys);
439
fprintf_plus(stderr, "The number of new signatures: %d\n",
440
import_result->new_signatures);
441
fprintf_plus(stderr, "The number of new revocations: %d\n",
442
import_result->new_revocations);
444
"The total number of secret keys read: %d\n",
445
import_result->secret_read);
447
"The number of imported secret keys: %d\n",
448
import_result->secret_imported);
450
"The number of unchanged secret keys: %d\n",
451
import_result->secret_unchanged);
452
fprintf_plus(stderr, "The number of keys not imported: %d\n",
453
import_result->not_imported);
454
for(gpgme_import_status_t import_status
455
= import_result->imports;
456
import_status != NULL;
457
import_status = import_status->next){
458
fprintf_plus(stderr, "Import status for key: %s\n",
460
if(import_status->result != GPG_ERR_NO_ERROR){
461
fprintf_plus(stderr, "Import result: %s: %s\n",
462
gpgme_strsource(import_status->result),
463
gpgme_strerror(import_status->result));
465
fprintf_plus(stderr, "Key status:\n");
467
import_status->status & GPGME_IMPORT_NEW
468
? "The key was new.\n"
469
: "The key was not new.\n");
471
import_status->status & GPGME_IMPORT_UID
472
? "The key contained new user IDs.\n"
473
: "The key did not contain new user IDs.\n");
475
import_status->status & GPGME_IMPORT_SIG
476
? "The key contained new signatures.\n"
477
: "The key did not contain new signatures.\n");
479
import_status->status & GPGME_IMPORT_SUBKEY
480
? "The key contained new sub keys.\n"
481
: "The key did not contain new sub keys.\n");
483
import_status->status & GPGME_IMPORT_SECRET
484
? "The key contained a secret key.\n"
485
: "The key did not contain a secret key.\n");
493
perror_plus("close");
186
495
gpgme_data_release(pgp_data);
191
fprintf(stderr, "Initialize gpgme\n");
500
fprintf_plus(stderr, "Initializing GPGME\n");
195
504
gpgme_check_version(NULL);
196
505
rc = gpgme_engine_check_version(GPGME_PROTOCOL_OpenPGP);
197
if (rc != GPG_ERR_NO_ERROR){
198
fprintf(stderr, "bad gpgme_engine_check_version: %s: %s\n",
199
gpgme_strsource(rc), gpgme_strerror(rc));
506
if(rc != GPG_ERR_NO_ERROR){
507
fprintf_plus(stderr, "bad gpgme_engine_check_version: %s: %s\n",
508
gpgme_strsource(rc), gpgme_strerror(rc));
203
/* Set GPGME home directory for the OpenPGP engine only */
204
rc = gpgme_get_engine_info (&engine_info);
205
if (rc != GPG_ERR_NO_ERROR){
206
fprintf(stderr, "bad gpgme_get_engine_info: %s: %s\n",
207
gpgme_strsource(rc), gpgme_strerror(rc));
512
/* Set GPGME home directory for the OpenPGP engine only */
513
rc = gpgme_get_engine_info(&engine_info);
514
if(rc != GPG_ERR_NO_ERROR){
515
fprintf_plus(stderr, "bad gpgme_get_engine_info: %s: %s\n",
516
gpgme_strsource(rc), gpgme_strerror(rc));
210
519
while(engine_info != NULL){
499
996
static void empty_log(__attribute__((unused)) AvahiLogLevel level,
500
997
__attribute__((unused)) const char *txt){}
999
/* Helper function to add_local_route() and delete_local_route() */
1000
__attribute__((nonnull, warn_unused_result))
1001
static bool add_delete_local_route(const bool add,
1002
const char *address,
1003
AvahiIfIndex if_index){
1005
char helper[] = "mandos-client-iprouteadddel";
1006
char add_arg[] = "add";
1007
char delete_arg[] = "delete";
1008
char debug_flag[] = "--debug";
1009
char *pluginhelperdir = getenv("MANDOSPLUGINHELPERDIR");
1010
if(pluginhelperdir == NULL){
1012
fprintf_plus(stderr, "MANDOSPLUGINHELPERDIR environment"
1013
" variable not set; cannot run helper\n");
1018
char interface[IF_NAMESIZE];
1019
if(if_indextoname((unsigned int)if_index, interface) == NULL){
1020
perror_plus("if_indextoname");
1024
int devnull = (int)TEMP_FAILURE_RETRY(open("/dev/null", O_RDONLY));
1026
perror_plus("open(\"/dev/null\", O_RDONLY)");
1032
/* Raise privileges */
1033
errno = raise_privileges_permanently();
1035
perror_plus("Failed to raise privileges");
1036
/* _exit(EX_NOPERM); */
1042
perror_plus("setgid");
1045
/* Reset supplementary groups */
1047
ret = setgroups(0, NULL);
1049
perror_plus("setgroups");
1053
ret = dup2(devnull, STDIN_FILENO);
1055
perror_plus("dup2(devnull, STDIN_FILENO)");
1058
ret = close(devnull);
1060
perror_plus("close");
1063
ret = dup2(STDERR_FILENO, STDOUT_FILENO);
1065
perror_plus("dup2(STDERR_FILENO, STDOUT_FILENO)");
1068
int helperdir_fd = (int)TEMP_FAILURE_RETRY(open(pluginhelperdir,
1073
if(helperdir_fd == -1){
1074
perror_plus("open");
1075
_exit(EX_UNAVAILABLE);
1077
int helper_fd = (int)TEMP_FAILURE_RETRY(openat(helperdir_fd,
1079
if(helper_fd == -1){
1080
perror_plus("openat");
1081
close(helperdir_fd);
1082
_exit(EX_UNAVAILABLE);
1084
close(helperdir_fd);
1086
#pragma GCC diagnostic push
1087
#pragma GCC diagnostic ignored "-Wcast-qual"
1089
if(fexecve(helper_fd, (char *const [])
1090
{ helper, add ? add_arg : delete_arg, (char *)address,
1091
interface, debug ? debug_flag : NULL, NULL },
1094
#pragma GCC diagnostic pop
1096
perror_plus("fexecve");
1097
_exit(EXIT_FAILURE);
1101
perror_plus("fork");
1108
pret = waitpid(pid, &status, 0);
1109
if(pret == -1 and errno == EINTR and quit_now){
1110
int errno_raising = 0;
1111
if((errno = raise_privileges()) != 0){
1112
errno_raising = errno;
1113
perror_plus("Failed to raise privileges in order to"
1114
" kill helper program");
1116
if(kill(pid, SIGTERM) == -1){
1117
perror_plus("kill");
1119
if((errno_raising == 0) and (errno = lower_privileges()) != 0){
1120
perror_plus("Failed to lower privileges after killing"
1125
} while(pret == -1 and errno == EINTR);
1127
perror_plus("waitpid");
1130
if(WIFEXITED(status)){
1131
if(WEXITSTATUS(status) != 0){
1132
fprintf_plus(stderr, "Error: iprouteadddel exited"
1133
" with status %d\n", WEXITSTATUS(status));
1138
if(WIFSIGNALED(status)){
1139
fprintf_plus(stderr, "Error: iprouteadddel died by"
1140
" signal %d\n", WTERMSIG(status));
1143
fprintf_plus(stderr, "Error: iprouteadddel crashed\n");
1147
__attribute__((nonnull, warn_unused_result))
1148
static bool add_local_route(const char *address,
1149
AvahiIfIndex if_index){
1151
fprintf_plus(stderr, "Adding route to %s\n", address);
1153
return add_delete_local_route(true, address, if_index);
1156
__attribute__((nonnull, warn_unused_result))
1157
static bool delete_local_route(const char *address,
1158
AvahiIfIndex if_index){
1160
fprintf_plus(stderr, "Removing route to %s\n", address);
1162
return add_delete_local_route(false, address, if_index);
502
1165
/* Called when a Mandos server is found */
503
static int start_mandos_communication(const char *ip, uint16_t port,
1166
__attribute__((nonnull, warn_unused_result))
1167
static int start_mandos_communication(const char *ip, in_port_t port,
504
1168
AvahiIfIndex if_index,
507
union { struct sockaddr in; struct sockaddr_in6 in6; } to;
1169
int af, mandos_context *mc){
1170
int ret, tcp_sd = -1;
1172
struct sockaddr_storage to;
508
1173
char *buffer = NULL;
509
char *decrypted_buffer;
1174
char *decrypted_buffer = NULL;
510
1175
size_t buffer_length = 0;
511
1176
size_t buffer_capacity = 0;
512
ssize_t decrypted_buffer_size;
515
char interface[IF_NAMESIZE];
516
1179
gnutls_session_t session;
518
ret = init_gnutls_session (mc, &session);
524
fprintf(stderr, "Setting up a tcp connection to %s, port %" PRIu16
528
tcp_sd = socket(PF_INET6, SOCK_STREAM, 0);
535
if(if_indextoname((unsigned int)if_index, interface) == NULL){
536
perror("if_indextoname");
1180
int pf; /* Protocol family */
1181
bool route_added = false;
1198
fprintf_plus(stderr, "Bad address family: %d\n", af);
1203
/* If the interface is specified and we have a list of interfaces */
1204
if(if_index != AVAHI_IF_UNSPEC and mc->interfaces != NULL){
1205
/* Check if the interface is one of the interfaces we are using */
1208
char *interface = NULL;
1209
while((interface = argz_next(mc->interfaces,
1210
mc->interfaces_size,
1212
if(if_nametoindex(interface) == (unsigned int)if_index){
1219
/* This interface does not match any in the list, so we don't
1220
connect to the server */
1222
char interface[IF_NAMESIZE];
1223
if(if_indextoname((unsigned int)if_index, interface) == NULL){
1224
perror_plus("if_indextoname");
1226
fprintf_plus(stderr, "Skipping server on non-used interface"
1228
if_indextoname((unsigned int)if_index,
539
fprintf(stderr, "Binding to interface %s\n", interface);
542
memset(&to, 0, sizeof(to));
543
to.in6.sin6_family = AF_INET6;
544
/* It would be nice to have a way to detect if we were passed an
545
IPv4 address here. Now we assume an IPv6 address. */
546
ret = inet_pton(AF_INET6, ip, &to.in6.sin6_addr);
1236
ret = init_gnutls_session(&session, mc);
1242
fprintf_plus(stderr, "Setting up a TCP connection to %s, port %"
1243
PRIuMAX "\n", ip, (uintmax_t)port);
1246
tcp_sd = socket(pf, SOCK_STREAM | SOCK_CLOEXEC, 0);
1249
perror_plus("socket");
1260
struct sockaddr_in6 *to6 = (struct sockaddr_in6 *)&to;
1261
*to6 = (struct sockaddr_in6){ .sin6_family = (sa_family_t)af };
1262
ret = inet_pton(af, ip, &to6->sin6_addr);
1264
struct sockaddr_in *to4 = (struct sockaddr_in *)&to;
1265
*to4 = (struct sockaddr_in){ .sin_family = (sa_family_t)af };
1266
ret = inet_pton(af, ip, &to4->sin_addr);
1270
perror_plus("inet_pton");
552
fprintf(stderr, "Bad address: %s\n", ip);
555
to.in6.sin6_port = htons(port); /* Spurious warning */
1276
fprintf_plus(stderr, "Bad address: %s\n", ip);
1281
((struct sockaddr_in6 *)&to)->sin6_port = htons(port);
1282
if(IN6_IS_ADDR_LINKLOCAL
1283
(&((struct sockaddr_in6 *)&to)->sin6_addr)){
1284
if(if_index == AVAHI_IF_UNSPEC){
1285
fprintf_plus(stderr, "An IPv6 link-local address is"
1286
" incomplete without a network interface\n");
1290
/* Set the network interface number as scope */
1291
((struct sockaddr_in6 *)&to)->sin6_scope_id = (uint32_t)if_index;
1294
((struct sockaddr_in *)&to)->sin_port = htons(port);
557
to.in6.sin6_scope_id = (uint32_t)if_index;
560
fprintf(stderr, "Connection to: %s, port %" PRIu16 "\n", ip,
562
char addrstr[INET6_ADDRSTRLEN] = "";
563
if(inet_ntop(to.in6.sin6_family, &(to.in6.sin6_addr), addrstr,
564
sizeof(addrstr)) == NULL){
567
if(strcmp(addrstr, ip) != 0){
568
fprintf(stderr, "Canonical address form: %s\n", addrstr);
573
ret = connect(tcp_sd, &to.in, sizeof(to));
1303
if(af == AF_INET6 and if_index != AVAHI_IF_UNSPEC){
1304
char interface[IF_NAMESIZE];
1305
if(if_indextoname((unsigned int)if_index, interface) == NULL){
1306
perror_plus("if_indextoname");
1308
fprintf_plus(stderr, "Connection to: %s%%%s, port %" PRIuMAX
1309
"\n", ip, interface, (uintmax_t)port);
1312
fprintf_plus(stderr, "Connection to: %s, port %" PRIuMAX "\n",
1313
ip, (uintmax_t)port);
1315
char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?
1316
INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";
1318
ret = getnameinfo((struct sockaddr *)&to,
1319
sizeof(struct sockaddr_in6),
1320
addrstr, sizeof(addrstr), NULL, 0,
1323
ret = getnameinfo((struct sockaddr *)&to,
1324
sizeof(struct sockaddr_in),
1325
addrstr, sizeof(addrstr), NULL, 0,
1328
if(ret == EAI_SYSTEM){
1329
perror_plus("getnameinfo");
1330
} else if(ret != 0) {
1331
fprintf_plus(stderr, "getnameinfo: %s", gai_strerror(ret));
1332
} else if(strcmp(addrstr, ip) != 0){
1333
fprintf_plus(stderr, "Canonical address form: %s\n", addrstr);
1344
ret = connect(tcp_sd, (struct sockaddr *)&to,
1345
sizeof(struct sockaddr_in6));
1347
ret = connect(tcp_sd, (struct sockaddr *)&to, /* IPv4 */
1348
sizeof(struct sockaddr_in));
1351
if(((errno == ENETUNREACH) or (errno == EHOSTUNREACH))
1352
and if_index != AVAHI_IF_UNSPEC
1353
and connect_to == NULL
1354
and not route_added and
1355
((af == AF_INET6 and not
1356
IN6_IS_ADDR_LINKLOCAL(&(((struct sockaddr_in6 *)
1358
or (af == AF_INET and
1359
/* Not a a IPv4LL address */
1360
(ntohl(((struct sockaddr_in *)&to)->sin_addr.s_addr)
1361
& 0xFFFF0000L) != 0xA9FE0000L))){
1362
/* Work around Avahi bug - Avahi does not announce link-local
1363
addresses if it has a global address, so local hosts with
1364
*only* a link-local address (e.g. Mandos clients) cannot
1365
connect to a Mandos server announced by Avahi on a server
1366
host with a global address. Work around this by retrying
1367
with an explicit route added with the server's address.
1369
Avahi bug reference:
1370
https://lists.freedesktop.org/archives/avahi/2010-February/001833.html
1371
https://bugs.debian.org/587961
1374
fprintf_plus(stderr, "Mandos server unreachable, trying"
1378
route_added = add_local_route(ip, if_index);
1384
if(errno != ECONNREFUSED or debug){
1386
perror_plus("connect");
579
1399
const char *out = mandos_protocol_version;
582
1402
size_t out_size = strlen(out);
583
ret = TEMP_FAILURE_RETRY(write(tcp_sd, out + written,
584
out_size - written));
1403
ret = (int)TEMP_FAILURE_RETRY(write(tcp_sd, out + written,
1404
out_size - written));
1407
perror_plus("write");
588
1409
goto mandos_end;
590
1411
written += (size_t)ret;
591
1412
if(written < out_size){
594
if (out == mandos_protocol_version){
1415
if(out == mandos_protocol_version){
604
fprintf(stderr, "Establishing TLS session with %s\n", ip);
607
gnutls_transport_set_ptr (session, (gnutls_transport_ptr_t) tcp_sd);
610
ret = gnutls_handshake (session);
1430
fprintf_plus(stderr, "Establishing TLS session with %s\n", ip);
1438
/* This casting via intptr_t is to eliminate warning about casting
1439
an int to a pointer type. This is exactly how the GnuTLS Guile
1440
function "set-session-transport-fd!" does it. */
1441
gnutls_transport_set_ptr(session,
1442
(gnutls_transport_ptr_t)(intptr_t)tcp_sd);
1450
ret = gnutls_handshake(session);
611
1455
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
613
if (ret != GNUTLS_E_SUCCESS){
1457
if(ret != GNUTLS_E_SUCCESS){
615
fprintf(stderr, "*** GnuTLS Handshake failed ***\n");
1459
fprintf_plus(stderr, "*** GnuTLS Handshake failed ***\n");
619
1463
goto mandos_end;
622
1466
/* Read OpenPGP packet that contains the wanted password */
625
fprintf(stderr, "Retrieving pgp encrypted password from %s\n",
1469
fprintf_plus(stderr, "Retrieving OpenPGP encrypted password from"
630
buffer_capacity = adjustbuffer(&buffer, buffer_length,
632
if (buffer_capacity == 0){
633
perror("adjustbuffer");
638
ret = gnutls_record_recv(session, buffer+buffer_length,
1480
buffer_capacity = incbuffer(&buffer, buffer_length,
1482
if(buffer_capacity == 0){
1484
perror_plus("incbuffer");
1494
sret = gnutls_record_recv(session, buffer+buffer_length,
645
1501
case GNUTLS_E_INTERRUPTED:
646
1502
case GNUTLS_E_AGAIN:
648
1504
case GNUTLS_E_REHANDSHAKE:
650
ret = gnutls_handshake (session);
1506
ret = gnutls_handshake(session);
651
1512
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
653
fprintf(stderr, "*** GnuTLS Re-handshake failed ***\n");
1514
fprintf_plus(stderr, "*** GnuTLS Re-handshake failed "
656
1518
goto mandos_end;
660
fprintf(stderr, "Unknown error while reading data from"
661
" encrypted session with Mandos server\n");
663
gnutls_bye (session, GNUTLS_SHUT_RDWR);
1522
fprintf_plus(stderr, "Unknown error while reading data from"
1523
" encrypted session with Mandos server\n");
1524
gnutls_bye(session, GNUTLS_SHUT_RDWR);
664
1526
goto mandos_end;
667
buffer_length += (size_t) ret;
1529
buffer_length += (size_t) sret;
672
fprintf(stderr, "Closing TLS session\n");
675
gnutls_bye (session, GNUTLS_SHUT_RDWR);
677
if (buffer_length > 0){
678
decrypted_buffer_size = pgp_packet_decrypt(mc, buffer,
681
if (decrypted_buffer_size >= 0){
1534
fprintf_plus(stderr, "Closing TLS session\n");
1543
ret = gnutls_bye(session, GNUTLS_SHUT_RDWR);
1548
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
1550
if(buffer_length > 0){
1551
ssize_t decrypted_buffer_size;
1552
decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,
1553
&decrypted_buffer, mc);
1554
if(decrypted_buffer_size >= 0){
683
1558
while(written < (size_t) decrypted_buffer_size){
684
ret = (int)fwrite (decrypted_buffer + written, 1,
685
(size_t)decrypted_buffer_size - written,
1564
ret = (int)fwrite(decrypted_buffer + written, 1,
1565
(size_t)decrypted_buffer_size - written,
687
1567
if(ret == 0 and ferror(stdout)){
689
fprintf(stderr, "Error writing encrypted data: %s\n",
1570
fprintf_plus(stderr, "Error writing encrypted data: %s\n",
695
1576
written += (size_t)ret;
697
free(decrypted_buffer);
1578
ret = fflush(stdout);
1582
fprintf_plus(stderr, "Error writing encrypted data: %s\n",
705
1592
/* Shutdown procedure */
709
ret = TEMP_FAILURE_RETRY(close(tcp_sd));
1597
if(not delete_local_route(ip, if_index)){
1598
fprintf_plus(stderr, "Failed to delete local route to %s on"
1599
" interface %d", ip, if_index);
1603
free(decrypted_buffer);
1606
ret = close(tcp_sd);
1612
perror_plus("close");
1614
gnutls_deinit(session);
713
gnutls_deinit (session);
717
1624
static void resolve_callback(AvahiSServiceResolver *r,
718
1625
AvahiIfIndex interface,
719
AVAHI_GCC_UNUSED AvahiProtocol protocol,
1626
AvahiProtocol proto,
720
1627
AvahiResolverEvent event,
721
1628
const char *name,
722
1629
const char *type,
805
1738
case AVAHI_BROWSER_ALL_FOR_NOW:
806
1739
case AVAHI_BROWSER_CACHE_EXHAUSTED:
808
fprintf(stderr, "No Mandos server found, still searching...\n");
1741
fprintf_plus(stderr, "No Mandos server found, still"
1748
/* Signal handler that stops main loop after SIGTERM */
1749
static void handle_sigterm(int sig){
1754
signal_received = sig;
1755
int old_errno = errno;
1756
/* set main loop to exit */
1757
if(simple_poll != NULL){
1758
avahi_simple_poll_quit(simple_poll);
1763
__attribute__((nonnull, warn_unused_result))
1764
bool get_flags(const char *ifname, struct ifreq *ifr){
1768
int s = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1771
perror_plus("socket");
1775
strncpy(ifr->ifr_name, ifname, IF_NAMESIZE);
1776
ifr->ifr_name[IF_NAMESIZE-1] = '\0'; /* NUL terminate */
1777
ret = ioctl(s, SIOCGIFFLAGS, ifr);
1781
perror_plus("ioctl SIOCGIFFLAGS");
1784
if((close(s) == -1) and debug){
1786
perror_plus("close");
1791
if((close(s) == -1) and debug){
1793
perror_plus("close");
1799
__attribute__((nonnull, warn_unused_result))
1800
bool good_flags(const char *ifname, const struct ifreq *ifr){
1802
/* Reject the loopback device */
1803
if(ifr->ifr_flags & IFF_LOOPBACK){
1805
fprintf_plus(stderr, "Rejecting loopback interface \"%s\"\n",
1810
/* Accept point-to-point devices only if connect_to is specified */
1811
if(connect_to != NULL and (ifr->ifr_flags & IFF_POINTOPOINT)){
1813
fprintf_plus(stderr, "Accepting point-to-point interface"
1814
" \"%s\"\n", ifname);
1818
/* Otherwise, reject non-broadcast-capable devices */
1819
if(not (ifr->ifr_flags & IFF_BROADCAST)){
1821
fprintf_plus(stderr, "Rejecting non-broadcast interface"
1822
" \"%s\"\n", ifname);
1826
/* Reject non-ARP interfaces (including dummy interfaces) */
1827
if(ifr->ifr_flags & IFF_NOARP){
1829
fprintf_plus(stderr, "Rejecting non-ARP interface \"%s\"\n",
1835
/* Accept this device */
1837
fprintf_plus(stderr, "Interface \"%s\" is good\n", ifname);
1843
* This function determines if a directory entry in /sys/class/net
1844
* corresponds to an acceptable network device.
1845
* (This function is passed to scandir(3) as a filter function.)
1847
__attribute__((nonnull, warn_unused_result))
1848
int good_interface(const struct dirent *if_entry){
1849
if(if_entry->d_name[0] == '.'){
1854
if(not get_flags(if_entry->d_name, &ifr)){
1856
fprintf_plus(stderr, "Failed to get flags for interface "
1857
"\"%s\"\n", if_entry->d_name);
1862
if(not good_flags(if_entry->d_name, &ifr)){
1869
* This function determines if a network interface is up.
1871
__attribute__((nonnull, warn_unused_result))
1872
bool interface_is_up(const char *interface){
1874
if(not get_flags(interface, &ifr)){
1876
fprintf_plus(stderr, "Failed to get flags for interface "
1877
"\"%s\"\n", interface);
1882
return (bool)(ifr.ifr_flags & IFF_UP);
1886
* This function determines if a network interface is running
1888
__attribute__((nonnull, warn_unused_result))
1889
bool interface_is_running(const char *interface){
1891
if(not get_flags(interface, &ifr)){
1893
fprintf_plus(stderr, "Failed to get flags for interface "
1894
"\"%s\"\n", interface);
1899
return (bool)(ifr.ifr_flags & IFF_RUNNING);
1902
__attribute__((nonnull, pure, warn_unused_result))
1903
int notdotentries(const struct dirent *direntry){
1904
/* Skip "." and ".." */
1905
if(direntry->d_name[0] == '.'
1906
and (direntry->d_name[1] == '\0'
1907
or (direntry->d_name[1] == '.'
1908
and direntry->d_name[2] == '\0'))){
1914
/* Is this directory entry a runnable program? */
1915
__attribute__((nonnull, warn_unused_result))
1916
int runnable_hook(const struct dirent *direntry){
1921
if((direntry->d_name)[0] == '\0'){
1926
sret = strspn(direntry->d_name, "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
1927
"abcdefghijklmnopqrstuvwxyz"
1930
if((direntry->d_name)[sret] != '\0'){
1931
/* Contains non-allowed characters */
1933
fprintf_plus(stderr, "Ignoring hook \"%s\" with bad name\n",
1939
ret = fstatat(hookdir_fd, direntry->d_name, &st, 0);
1942
perror_plus("Could not stat hook");
1946
if(not (S_ISREG(st.st_mode))){
1947
/* Not a regular file */
1949
fprintf_plus(stderr, "Ignoring hook \"%s\" - not a file\n",
1954
if(not (st.st_mode & (S_IXUSR | S_IXGRP | S_IXOTH))){
1955
/* Not executable */
1957
fprintf_plus(stderr, "Ignoring hook \"%s\" - not executable\n",
1963
fprintf_plus(stderr, "Hook \"%s\" is acceptable\n",
1969
__attribute__((nonnull, warn_unused_result))
1970
int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,
1971
mandos_context *mc){
1973
struct timespec now;
1974
struct timespec waited_time;
1975
intmax_t block_time;
1978
if(mc->current_server == NULL){
1980
fprintf_plus(stderr, "Wait until first server is found."
1983
ret = avahi_simple_poll_iterate(s, -1);
1986
fprintf_plus(stderr, "Check current_server if we should run"
1989
/* the current time */
1990
ret = clock_gettime(CLOCK_MONOTONIC, &now);
1992
perror_plus("clock_gettime");
1995
/* Calculating in ms how long time between now and server
1996
who we visted longest time ago. Now - last seen. */
1997
waited_time.tv_sec = (now.tv_sec
1998
- mc->current_server->last_seen.tv_sec);
1999
waited_time.tv_nsec = (now.tv_nsec
2000
- mc->current_server->last_seen.tv_nsec);
2001
/* total time is 10s/10,000ms.
2002
Converting to s from ms by dividing by 1,000,
2003
and ns to ms by dividing by 1,000,000. */
2004
block_time = ((retry_interval
2005
- ((intmax_t)waited_time.tv_sec * 1000))
2006
- ((intmax_t)waited_time.tv_nsec / 1000000));
2009
fprintf_plus(stderr, "Blocking for %" PRIdMAX " ms\n",
2013
if(block_time <= 0){
2014
ret = start_mandos_communication(mc->current_server->ip,
2015
mc->current_server->port,
2016
mc->current_server->if_index,
2017
mc->current_server->af, mc);
2019
avahi_simple_poll_quit(s);
2022
ret = clock_gettime(CLOCK_MONOTONIC,
2023
&mc->current_server->last_seen);
2025
perror_plus("clock_gettime");
2028
mc->current_server = mc->current_server->next;
2029
block_time = 0; /* Call avahi to find new Mandos
2030
servers, but don't block */
2033
ret = avahi_simple_poll_iterate(s, (int)block_time);
2036
if(ret > 0 or errno != EINTR){
2037
return (ret != 1) ? ret : 0;
2043
__attribute__((nonnull))
2044
void run_network_hooks(const char *mode, const char *interface,
2046
struct dirent **direntries = NULL;
2047
if(hookdir_fd == -1){
2048
hookdir_fd = open(hookdir, O_RDONLY | O_DIRECTORY | O_PATH
2050
if(hookdir_fd == -1){
2051
if(errno == ENOENT){
2053
fprintf_plus(stderr, "Network hook directory \"%s\" not"
2054
" found\n", hookdir);
2057
perror_plus("open");
2062
int devnull = (int)TEMP_FAILURE_RETRY(open("/dev/null", O_RDONLY));
2064
perror_plus("open(\"/dev/null\", O_RDONLY)");
2067
int numhooks = scandirat(hookdir_fd, ".", &direntries,
2068
runnable_hook, alphasort);
2070
perror_plus("scandir");
2074
struct dirent *direntry;
2076
for(int i = 0; i < numhooks; i++){
2077
direntry = direntries[i];
2079
fprintf_plus(stderr, "Running network hook \"%s\"\n",
2082
pid_t hook_pid = fork();
2085
/* Raise privileges */
2086
errno = raise_privileges_permanently();
2088
perror_plus("Failed to raise privileges");
2095
perror_plus("setgid");
2098
/* Reset supplementary groups */
2100
ret = setgroups(0, NULL);
2102
perror_plus("setgroups");
2105
ret = setenv("MANDOSNETHOOKDIR", hookdir, 1);
2107
perror_plus("setenv");
2110
ret = setenv("DEVICE", interface, 1);
2112
perror_plus("setenv");
2115
ret = setenv("VERBOSITY", debug ? "1" : "0", 1);
2117
perror_plus("setenv");
2120
ret = setenv("MODE", mode, 1);
2122
perror_plus("setenv");
2126
ret = asprintf(&delaystring, "%f", (double)delay);
2128
perror_plus("asprintf");
2131
ret = setenv("DELAY", delaystring, 1);
2134
perror_plus("setenv");
2138
if(connect_to != NULL){
2139
ret = setenv("CONNECT", connect_to, 1);
2141
perror_plus("setenv");
2145
int hook_fd = (int)TEMP_FAILURE_RETRY(openat(hookdir_fd,
2149
perror_plus("openat");
2150
_exit(EXIT_FAILURE);
2152
if(close(hookdir_fd) == -1){
2153
perror_plus("close");
2154
_exit(EXIT_FAILURE);
2156
ret = dup2(devnull, STDIN_FILENO);
2158
perror_plus("dup2(devnull, STDIN_FILENO)");
2161
ret = close(devnull);
2163
perror_plus("close");
2166
ret = dup2(STDERR_FILENO, STDOUT_FILENO);
2168
perror_plus("dup2(STDERR_FILENO, STDOUT_FILENO)");
2171
if(fexecve(hook_fd, (char *const []){ direntry->d_name, NULL },
2173
perror_plus("fexecve");
2174
_exit(EXIT_FAILURE);
2178
perror_plus("fork");
2183
if(TEMP_FAILURE_RETRY(waitpid(hook_pid, &status, 0)) == -1){
2184
perror_plus("waitpid");
2188
if(WIFEXITED(status)){
2189
if(WEXITSTATUS(status) != 0){
2190
fprintf_plus(stderr, "Warning: network hook \"%s\" exited"
2191
" with status %d\n", direntry->d_name,
2192
WEXITSTATUS(status));
2196
} else if(WIFSIGNALED(status)){
2197
fprintf_plus(stderr, "Warning: network hook \"%s\" died by"
2198
" signal %d\n", direntry->d_name,
2203
fprintf_plus(stderr, "Warning: network hook \"%s\""
2204
" crashed\n", direntry->d_name);
2210
fprintf_plus(stderr, "Network hook \"%s\" ran successfully\n",
2216
if(close(hookdir_fd) == -1){
2217
perror_plus("close");
2224
__attribute__((nonnull, warn_unused_result))
2225
int bring_up_interface(const char *const interface,
2227
int old_errno = errno;
2229
struct ifreq network;
2230
unsigned int if_index = if_nametoindex(interface);
2232
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
2242
if(not interface_is_up(interface)){
2244
int ioctl_errno = 0;
2245
if(not get_flags(interface, &network)){
2247
fprintf_plus(stderr, "Failed to get flags for interface "
2248
"\"%s\"\n", interface);
2252
network.ifr_flags |= IFF_UP; /* set flag */
2254
int sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
2257
perror_plus("socket");
2265
perror_plus("close");
2272
fprintf_plus(stderr, "Bringing up interface \"%s\"\n",
2276
/* Raise privileges */
2277
ret_errno = raise_privileges();
2280
perror_plus("Failed to raise privileges");
2285
bool restore_loglevel = false;
2287
/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO
2288
messages about the network interface to mess up the prompt */
2289
ret_linux = klogctl(8, NULL, 5);
2290
if(ret_linux == -1){
2291
perror_plus("klogctl");
2293
restore_loglevel = true;
2296
#endif /* __linux__ */
2297
int ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
2298
ioctl_errno = errno;
2300
if(restore_loglevel){
2301
ret_linux = klogctl(7, NULL, 0);
2302
if(ret_linux == -1){
2303
perror_plus("klogctl");
2306
#endif /* __linux__ */
2308
/* If raise_privileges() succeeded above */
2310
/* Lower privileges */
2311
ret_errno = lower_privileges();
2314
perror_plus("Failed to lower privileges");
2318
/* Close the socket */
2321
perror_plus("close");
2324
if(ret_setflags == -1){
2325
errno = ioctl_errno;
2326
perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");
2331
fprintf_plus(stderr, "Interface \"%s\" is already up; good\n",
2335
/* Sleep checking until interface is running.
2336
Check every 0.25s, up to total time of delay */
2337
for(int i = 0; i < delay * 4; i++){
2338
if(interface_is_running(interface)){
2341
struct timespec sleeptime = { .tv_nsec = 250000000 };
2342
ret = nanosleep(&sleeptime, NULL);
2343
if(ret == -1 and errno != EINTR){
2344
perror_plus("nanosleep");
2352
__attribute__((nonnull, warn_unused_result))
2353
int take_down_interface(const char *const interface){
2354
int old_errno = errno;
2355
struct ifreq network;
2356
unsigned int if_index = if_nametoindex(interface);
2358
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
2362
if(interface_is_up(interface)){
2364
int ioctl_errno = 0;
2365
if(not get_flags(interface, &network) and debug){
2367
fprintf_plus(stderr, "Failed to get flags for interface "
2368
"\"%s\"\n", interface);
2372
network.ifr_flags &= ~(short)IFF_UP; /* clear flag */
2374
int sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
2377
perror_plus("socket");
2383
fprintf_plus(stderr, "Taking down interface \"%s\"\n",
2387
/* Raise privileges */
2388
ret_errno = raise_privileges();
2391
perror_plus("Failed to raise privileges");
2394
int ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
2395
ioctl_errno = errno;
2397
/* If raise_privileges() succeeded above */
2399
/* Lower privileges */
2400
ret_errno = lower_privileges();
2403
perror_plus("Failed to lower privileges");
2407
/* Close the socket */
2408
int ret = close(sd);
2410
perror_plus("close");
2413
if(ret_setflags == -1){
2414
errno = ioctl_errno;
2415
perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");
2420
fprintf_plus(stderr, "Interface \"%s\" is already down; odd\n",
814
2428
int main(int argc, char *argv[]){
815
AvahiSServiceBrowser *sb = NULL;
818
int exitcode = EXIT_SUCCESS;
819
const char *interface = "eth0";
820
struct ifreq network;
824
char *connect_to = NULL;
825
char tempdir[] = "/tmp/mandosXXXXXX";
826
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
827
const char *seckey = PATHDIR "/" SECKEY;
828
const char *pubkey = PATHDIR "/" PUBKEY;
830
mandos_context mc = { .simple_poll = NULL, .server = NULL,
831
.dh_bits = 1024, .priority = "SECURE256"
832
":!CTYPE-X.509:+CTYPE-OPENPGP" };
833
bool gnutls_initalized = false;
834
bool gpgme_initalized = false;
837
struct argp_option options[] = {
838
{ .name = "debug", .key = 128,
839
.doc = "Debug mode", .group = 3 },
840
{ .name = "connect", .key = 'c',
841
.arg = "ADDRESS:PORT",
842
.doc = "Connect directly to a specific Mandos server",
844
{ .name = "interface", .key = 'i',
846
.doc = "Interface that will be used to search for Mandos"
849
{ .name = "seckey", .key = 's',
851
.doc = "OpenPGP secret key file base name",
853
{ .name = "pubkey", .key = 'p',
855
.doc = "OpenPGP public key file base name",
857
{ .name = "dh-bits", .key = 129,
859
.doc = "Bit length of the prime number used in the"
860
" Diffie-Hellman key exchange",
862
{ .name = "priority", .key = 130,
864
.doc = "GnuTLS priority string for the TLS handshake",
869
error_t parse_opt (int key, char *arg,
870
struct argp_state *state) {
871
/* Get the INPUT argument from `argp_parse', which we know is
872
a pointer to our plugin list pointer. */
874
case 128: /* --debug */
877
case 'c': /* --connect */
880
case 'i': /* --interface */
883
case 's': /* --seckey */
886
case 'p': /* --pubkey */
889
case 129: /* --dh-bits */
891
mc.dh_bits = (unsigned int) strtol(arg, NULL, 10);
897
case 130: /* --priority */
905
return ARGP_ERR_UNKNOWN;
910
struct argp argp = { .options = options, .parser = parse_opt,
912
.doc = "Mandos client -- Get and decrypt"
913
" passwords from a Mandos server" };
914
ret = argp_parse (&argp, argc, argv, 0, 0, NULL);
915
if (ret == ARGP_ERR_UNKNOWN){
916
fprintf(stderr, "Unknown error while parsing arguments\n");
917
exitcode = EXIT_FAILURE;
922
ret = init_gnutls_global(&mc, pubkey, seckey);
924
fprintf(stderr, "init_gnutls_global failed\n");
925
exitcode = EXIT_FAILURE;
928
gnutls_initalized = true;
931
if(mkdtemp(tempdir) == NULL){
937
if(not init_gpgme(&mc, pubkey, seckey, tempdir)){
938
fprintf(stderr, "gpgme_initalized failed\n");
939
exitcode = EXIT_FAILURE;
942
gpgme_initalized = true;
945
/* If the interface is down, bring it up */
947
sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
950
exitcode = EXIT_FAILURE;
953
strcpy(network.ifr_name, interface);
954
ret = ioctl(sd, SIOCGIFFLAGS, &network);
956
perror("ioctl SIOCGIFFLAGS");
957
exitcode = EXIT_FAILURE;
960
if((network.ifr_flags & IFF_UP) == 0){
961
network.ifr_flags |= IFF_UP;
962
ret = ioctl(sd, SIOCSIFFLAGS, &network);
964
perror("ioctl SIOCSIFFLAGS");
965
exitcode = EXIT_FAILURE;
969
ret = TEMP_FAILURE_RETRY(close(sd));
988
if_index = (AvahiIfIndex) if_nametoindex(interface);
990
fprintf(stderr, "No such interface: \"%s\"\n", interface);
994
if(connect_to != NULL){
995
/* Connect directly, do not use Zeroconf */
996
/* (Mainly meant for debugging) */
997
char *address = strrchr(connect_to, ':');
999
fprintf(stderr, "No colon in address\n");
1000
exitcode = EXIT_FAILURE;
2429
mandos_context mc = { .server = NULL, .dh_bits = 0,
2430
.priority = "SECURE256:!CTYPE-X.509"
2431
":+CTYPE-OPENPGP:!RSA:+SIGN-DSA-SHA256",
2432
.current_server = NULL, .interfaces = NULL,
2433
.interfaces_size = 0 };
2434
AvahiSServiceBrowser *sb = NULL;
2439
int exitcode = EXIT_SUCCESS;
2440
char *interfaces_to_take_down = NULL;
2441
size_t interfaces_to_take_down_size = 0;
2442
char run_tempdir[] = "/run/tmp/mandosXXXXXX";
2443
char old_tempdir[] = "/tmp/mandosXXXXXX";
2444
char *tempdir = NULL;
2445
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
2446
const char *seckey = PATHDIR "/" SECKEY;
2447
const char *pubkey = PATHDIR "/" PUBKEY;
2448
const char *dh_params_file = NULL;
2449
char *interfaces_hooks = NULL;
2451
bool gnutls_initialized = false;
2452
bool gpgme_initialized = false;
2454
double retry_interval = 10; /* 10s between trying a server and
2455
retrying the same server again */
2457
struct sigaction old_sigterm_action = { .sa_handler = SIG_DFL };
2458
struct sigaction sigterm_action = { .sa_handler = handle_sigterm };
2463
/* Lower any group privileges we might have, just to be safe */
2467
perror_plus("setgid");
2470
/* Lower user privileges (temporarily) */
2474
perror_plus("seteuid");
2482
struct argp_option options[] = {
2483
{ .name = "debug", .key = 128,
2484
.doc = "Debug mode", .group = 3 },
2485
{ .name = "connect", .key = 'c',
2486
.arg = "ADDRESS:PORT",
2487
.doc = "Connect directly to a specific Mandos server",
2489
{ .name = "interface", .key = 'i',
2491
.doc = "Network interface that will be used to search for"
2494
{ .name = "seckey", .key = 's',
2496
.doc = "OpenPGP secret key file base name",
2498
{ .name = "pubkey", .key = 'p',
2500
.doc = "OpenPGP public key file base name",
2502
{ .name = "dh-bits", .key = 129,
2504
.doc = "Bit length of the prime number used in the"
2505
" Diffie-Hellman key exchange",
2507
{ .name = "dh-params", .key = 134,
2509
.doc = "PEM-encoded PKCS#3 file with pre-generated parameters"
2510
" for the Diffie-Hellman key exchange",
2512
{ .name = "priority", .key = 130,
2514
.doc = "GnuTLS priority string for the TLS handshake",
2516
{ .name = "delay", .key = 131,
2518
.doc = "Maximum delay to wait for interface startup",
2520
{ .name = "retry", .key = 132,
2522
.doc = "Retry interval used when denied by the Mandos server",
2524
{ .name = "network-hook-dir", .key = 133,
2526
.doc = "Directory where network hooks are located",
2529
* These reproduce what we would get without ARGP_NO_HELP
2531
{ .name = "help", .key = '?',
2532
.doc = "Give this help list", .group = -1 },
2533
{ .name = "usage", .key = -3,
2534
.doc = "Give a short usage message", .group = -1 },
2535
{ .name = "version", .key = 'V',
2536
.doc = "Print program version", .group = -1 },
2540
error_t parse_opt(int key, char *arg,
2541
struct argp_state *state){
1004
uint16_t port = (uint16_t) strtol(address+1, NULL, 10);
1006
perror("Bad port number");
1007
exitcode = EXIT_FAILURE;
2544
case 128: /* --debug */
2547
case 'c': /* --connect */
2550
case 'i': /* --interface */
2551
ret_errno = argz_add_sep(&mc.interfaces, &mc.interfaces_size,
2554
argp_error(state, "%s", strerror(ret_errno));
2557
case 's': /* --seckey */
2560
case 'p': /* --pubkey */
2563
case 129: /* --dh-bits */
2565
tmpmax = strtoimax(arg, &tmp, 10);
2566
if(errno != 0 or tmp == arg or *tmp != '\0'
2567
or tmpmax != (typeof(mc.dh_bits))tmpmax){
2568
argp_error(state, "Bad number of DH bits");
2570
mc.dh_bits = (typeof(mc.dh_bits))tmpmax;
2572
case 134: /* --dh-params */
2573
dh_params_file = arg;
2575
case 130: /* --priority */
2578
case 131: /* --delay */
2580
delay = strtof(arg, &tmp);
2581
if(errno != 0 or tmp == arg or *tmp != '\0'){
2582
argp_error(state, "Bad delay");
2584
case 132: /* --retry */
2586
retry_interval = strtod(arg, &tmp);
2587
if(errno != 0 or tmp == arg or *tmp != '\0'
2588
or (retry_interval * 1000) > INT_MAX
2589
or retry_interval < 0){
2590
argp_error(state, "Bad retry interval");
2593
case 133: /* --network-hook-dir */
2597
* These reproduce what we would get without ARGP_NO_HELP
2599
case '?': /* --help */
2600
argp_state_help(state, state->out_stream,
2601
(ARGP_HELP_STD_HELP | ARGP_HELP_EXIT_ERR)
2602
& ~(unsigned int)ARGP_HELP_EXIT_OK);
2603
case -3: /* --usage */
2604
argp_state_help(state, state->out_stream,
2605
ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);
2606
case 'V': /* --version */
2607
fprintf_plus(state->out_stream, "%s\n", argp_program_version);
2608
exit(argp_err_exit_status);
2611
return ARGP_ERR_UNKNOWN;
2616
struct argp argp = { .options = options, .parser = parse_opt,
2618
.doc = "Mandos client -- Get and decrypt"
2619
" passwords from a Mandos server" };
2620
ret_errno = argp_parse(&argp, argc, argv,
2621
ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);
2628
perror_plus("argp_parse");
2629
exitcode = EX_OSERR;
2632
exitcode = EX_USAGE;
2638
/* Work around Debian bug #633582:
2639
<https://bugs.debian.org/633582> */
2641
/* Re-raise privileges */
2642
ret = raise_privileges();
2645
perror_plus("Failed to raise privileges");
2649
if(strcmp(seckey, PATHDIR "/" SECKEY) == 0){
2650
int seckey_fd = open(seckey, O_RDONLY);
2651
if(seckey_fd == -1){
2652
perror_plus("open");
2654
ret = (int)TEMP_FAILURE_RETRY(fstat(seckey_fd, &st));
2656
perror_plus("fstat");
2658
if(S_ISREG(st.st_mode)
2659
and st.st_uid == 0 and st.st_gid == 0){
2660
ret = fchown(seckey_fd, uid, gid);
2662
perror_plus("fchown");
2670
if(strcmp(pubkey, PATHDIR "/" PUBKEY) == 0){
2671
int pubkey_fd = open(pubkey, O_RDONLY);
2672
if(pubkey_fd == -1){
2673
perror_plus("open");
2675
ret = (int)TEMP_FAILURE_RETRY(fstat(pubkey_fd, &st));
2677
perror_plus("fstat");
2679
if(S_ISREG(st.st_mode)
2680
and st.st_uid == 0 and st.st_gid == 0){
2681
ret = fchown(pubkey_fd, uid, gid);
2683
perror_plus("fchown");
2691
if(dh_params_file != NULL
2692
and strcmp(dh_params_file, PATHDIR "/dhparams.pem" ) == 0){
2693
int dhparams_fd = open(dh_params_file, O_RDONLY);
2694
if(dhparams_fd == -1){
2695
perror_plus("open");
2697
ret = (int)TEMP_FAILURE_RETRY(fstat(dhparams_fd, &st));
2699
perror_plus("fstat");
2701
if(S_ISREG(st.st_mode)
2702
and st.st_uid == 0 and st.st_gid == 0){
2703
ret = fchown(dhparams_fd, uid, gid);
2705
perror_plus("fchown");
2713
/* Lower privileges */
2714
ret = lower_privileges();
2717
perror_plus("Failed to lower privileges");
2722
/* Remove invalid interface names (except "none") */
2724
char *interface = NULL;
2725
while((interface = argz_next(mc.interfaces, mc.interfaces_size,
2727
if(strcmp(interface, "none") != 0
2728
and if_nametoindex(interface) == 0){
2729
if(interface[0] != '\0'){
2730
fprintf_plus(stderr, "Not using nonexisting interface"
2731
" \"%s\"\n", interface);
2733
argz_delete(&mc.interfaces, &mc.interfaces_size, interface);
2739
/* Run network hooks */
2741
if(mc.interfaces != NULL){
2742
interfaces_hooks = malloc(mc.interfaces_size);
2743
if(interfaces_hooks == NULL){
2744
perror_plus("malloc");
1011
address = connect_to;
1012
ret = start_mandos_communication(address, port, if_index, &mc);
1014
exitcode = EXIT_FAILURE;
1016
exitcode = EXIT_SUCCESS;
1022
avahi_set_log_function(empty_log);
1025
/* Initialize the pseudo-RNG for Avahi */
1026
srand((unsigned int) time(NULL));
1028
/* Allocate main Avahi loop object */
1029
mc.simple_poll = avahi_simple_poll_new();
1030
if (mc.simple_poll == NULL) {
1031
fprintf(stderr, "Avahi: Failed to create simple poll"
1033
exitcode = EXIT_FAILURE;
1038
AvahiServerConfig config;
1039
/* Do not publish any local Zeroconf records */
1040
avahi_server_config_init(&config);
1041
config.publish_hinfo = 0;
1042
config.publish_addresses = 0;
1043
config.publish_workstation = 0;
1044
config.publish_domain = 0;
1046
/* Allocate a new server */
1047
mc.server = avahi_server_new(avahi_simple_poll_get
1048
(mc.simple_poll), &config, NULL,
1051
/* Free the Avahi configuration data */
1052
avahi_server_config_free(&config);
1055
/* Check if creating the Avahi server object succeeded */
1056
if (mc.server == NULL) {
1057
fprintf(stderr, "Failed to create Avahi server: %s\n",
1058
avahi_strerror(error));
1059
exitcode = EXIT_FAILURE;
1063
/* Create the Avahi service browser */
1064
sb = avahi_s_service_browser_new(mc.server, if_index,
1066
"_mandos._tcp", NULL, 0,
1067
browse_callback, &mc);
1069
fprintf(stderr, "Failed to create service browser: %s\n",
1070
avahi_strerror(avahi_server_errno(mc.server)));
1071
exitcode = EXIT_FAILURE;
1075
/* Run the main loop */
1078
fprintf(stderr, "Starting Avahi loop search\n");
1081
avahi_simple_poll_loop(mc.simple_poll);
2747
memcpy(interfaces_hooks, mc.interfaces, mc.interfaces_size);
2748
argz_stringify(interfaces_hooks, mc.interfaces_size, (int)',');
2750
run_network_hooks("start", interfaces_hooks != NULL ?
2751
interfaces_hooks : "", delay);
2755
avahi_set_log_function(empty_log);
2758
/* Initialize Avahi early so avahi_simple_poll_quit() can be called
2759
from the signal handler */
2760
/* Initialize the pseudo-RNG for Avahi */
2761
srand((unsigned int) time(NULL));
2762
simple_poll = avahi_simple_poll_new();
2763
if(simple_poll == NULL){
2764
fprintf_plus(stderr,
2765
"Avahi: Failed to create simple poll object.\n");
2766
exitcode = EX_UNAVAILABLE;
2770
sigemptyset(&sigterm_action.sa_mask);
2771
ret = sigaddset(&sigterm_action.sa_mask, SIGINT);
2773
perror_plus("sigaddset");
2774
exitcode = EX_OSERR;
2777
ret = sigaddset(&sigterm_action.sa_mask, SIGHUP);
2779
perror_plus("sigaddset");
2780
exitcode = EX_OSERR;
2783
ret = sigaddset(&sigterm_action.sa_mask, SIGTERM);
2785
perror_plus("sigaddset");
2786
exitcode = EX_OSERR;
2789
/* Need to check if the handler is SIG_IGN before handling:
2790
| [[info:libc:Initial Signal Actions]] |
2791
| [[info:libc:Basic Signal Handling]] |
2793
ret = sigaction(SIGINT, NULL, &old_sigterm_action);
2795
perror_plus("sigaction");
2798
if(old_sigterm_action.sa_handler != SIG_IGN){
2799
ret = sigaction(SIGINT, &sigterm_action, NULL);
2801
perror_plus("sigaction");
2802
exitcode = EX_OSERR;
2806
ret = sigaction(SIGHUP, NULL, &old_sigterm_action);
2808
perror_plus("sigaction");
2811
if(old_sigterm_action.sa_handler != SIG_IGN){
2812
ret = sigaction(SIGHUP, &sigterm_action, NULL);
2814
perror_plus("sigaction");
2815
exitcode = EX_OSERR;
2819
ret = sigaction(SIGTERM, NULL, &old_sigterm_action);
2821
perror_plus("sigaction");
2824
if(old_sigterm_action.sa_handler != SIG_IGN){
2825
ret = sigaction(SIGTERM, &sigterm_action, NULL);
2827
perror_plus("sigaction");
2828
exitcode = EX_OSERR;
2833
/* If no interfaces were specified, make a list */
2834
if(mc.interfaces == NULL){
2835
struct dirent **direntries = NULL;
2836
/* Look for any good interfaces */
2837
ret = scandir(sys_class_net, &direntries, good_interface,
2840
/* Add all found interfaces to interfaces list */
2841
for(int i = 0; i < ret; ++i){
2842
ret_errno = argz_add(&mc.interfaces, &mc.interfaces_size,
2843
direntries[i]->d_name);
2846
perror_plus("argz_add");
2847
free(direntries[i]);
2851
fprintf_plus(stderr, "Will use interface \"%s\"\n",
2852
direntries[i]->d_name);
2854
free(direntries[i]);
2861
fprintf_plus(stderr, "Could not find a network interface\n");
2862
exitcode = EXIT_FAILURE;
2867
/* Bring up interfaces which are down, and remove any "none"s */
2869
char *interface = NULL;
2870
while((interface = argz_next(mc.interfaces, mc.interfaces_size,
2872
/* If interface name is "none", stop bringing up interfaces.
2873
Also remove all instances of "none" from the list */
2874
if(strcmp(interface, "none") == 0){
2875
argz_delete(&mc.interfaces, &mc.interfaces_size,
2878
while((interface = argz_next(mc.interfaces,
2879
mc.interfaces_size, interface))){
2880
if(strcmp(interface, "none") == 0){
2881
argz_delete(&mc.interfaces, &mc.interfaces_size,
2888
bool interface_was_up = interface_is_up(interface);
2889
errno = bring_up_interface(interface, delay);
2890
if(not interface_was_up){
2892
fprintf_plus(stderr, "Failed to bring up interface \"%s\":"
2893
" %s\n", interface, strerror(errno));
2895
errno = argz_add(&interfaces_to_take_down,
2896
&interfaces_to_take_down_size,
2899
perror_plus("argz_add");
2904
if(debug and (interfaces_to_take_down == NULL)){
2905
fprintf_plus(stderr, "No interfaces were brought up\n");
2909
/* If we only got one interface, explicitly use only that one */
2910
if(argz_count(mc.interfaces, mc.interfaces_size) == 1){
2912
fprintf_plus(stderr, "Using only interface \"%s\"\n",
2915
if_index = (AvahiIfIndex)if_nametoindex(mc.interfaces);
2922
ret = init_gnutls_global(pubkey, seckey, dh_params_file, &mc);
2924
fprintf_plus(stderr, "init_gnutls_global failed\n");
2925
exitcode = EX_UNAVAILABLE;
2928
gnutls_initialized = true;
2935
/* Try /run/tmp before /tmp */
2936
tempdir = mkdtemp(run_tempdir);
2937
if(tempdir == NULL and errno == ENOENT){
2939
fprintf_plus(stderr, "Tempdir %s did not work, trying %s\n",
2940
run_tempdir, old_tempdir);
2942
tempdir = mkdtemp(old_tempdir);
2944
if(tempdir == NULL){
2945
perror_plus("mkdtemp");
2953
if(not init_gpgme(pubkey, seckey, tempdir, &mc)){
2954
fprintf_plus(stderr, "init_gpgme failed\n");
2955
exitcode = EX_UNAVAILABLE;
2958
gpgme_initialized = true;
2965
if(connect_to != NULL){
2966
/* Connect directly, do not use Zeroconf */
2967
/* (Mainly meant for debugging) */
2968
char *address = strrchr(connect_to, ':');
2970
if(address == NULL){
2971
fprintf_plus(stderr, "No colon in address\n");
2972
exitcode = EX_USAGE;
2982
tmpmax = strtoimax(address+1, &tmp, 10);
2983
if(errno != 0 or tmp == address+1 or *tmp != '\0'
2984
or tmpmax != (in_port_t)tmpmax){
2985
fprintf_plus(stderr, "Bad port number\n");
2986
exitcode = EX_USAGE;
2994
port = (in_port_t)tmpmax;
2996
/* Colon in address indicates IPv6 */
2998
if(strchr(connect_to, ':') != NULL){
3000
/* Accept [] around IPv6 address - see RFC 5952 */
3001
if(connect_to[0] == '[' and address[-1] == ']')
3009
address = connect_to;
3015
while(not quit_now){
3016
ret = start_mandos_communication(address, port, if_index, af,
3018
if(quit_now or ret == 0){
3022
fprintf_plus(stderr, "Retrying in %d seconds\n",
3023
(int)retry_interval);
3025
sleep((unsigned int)retry_interval);
3029
exitcode = EXIT_SUCCESS;
3040
AvahiServerConfig config;
3041
/* Do not publish any local Zeroconf records */
3042
avahi_server_config_init(&config);
3043
config.publish_hinfo = 0;
3044
config.publish_addresses = 0;
3045
config.publish_workstation = 0;
3046
config.publish_domain = 0;
3048
/* Allocate a new server */
3049
mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),
3050
&config, NULL, NULL, &ret);
3052
/* Free the Avahi configuration data */
3053
avahi_server_config_free(&config);
3056
/* Check if creating the Avahi server object succeeded */
3057
if(mc.server == NULL){
3058
fprintf_plus(stderr, "Failed to create Avahi server: %s\n",
3059
avahi_strerror(ret));
3060
exitcode = EX_UNAVAILABLE;
3068
/* Create the Avahi service browser */
3069
sb = avahi_s_service_browser_new(mc.server, if_index,
3070
AVAHI_PROTO_UNSPEC, "_mandos._tcp",
3071
NULL, 0, browse_callback,
3074
fprintf_plus(stderr, "Failed to create service browser: %s\n",
3075
avahi_strerror(avahi_server_errno(mc.server)));
3076
exitcode = EX_UNAVAILABLE;
3084
/* Run the main loop */
3087
fprintf_plus(stderr, "Starting Avahi loop search\n");
3090
ret = avahi_loop_with_timeout(simple_poll,
3091
(int)(retry_interval * 1000), &mc);
3093
fprintf_plus(stderr, "avahi_loop_with_timeout exited %s\n",
3094
(ret == 0) ? "successfully" : "with error");
1086
fprintf(stderr, "%s exiting\n", argv[0]);
1089
/* Cleanup things */
1091
avahi_s_service_browser_free(sb);
1093
if (mc.server != NULL)
1094
avahi_server_free(mc.server);
1096
if (mc.simple_poll != NULL)
1097
avahi_simple_poll_free(mc.simple_poll);
1099
if (gnutls_initalized){
1100
gnutls_certificate_free_credentials(mc.cred);
1101
gnutls_global_deinit ();
1102
gnutls_dh_params_deinit(mc.dh_params);
1105
if(gpgme_initalized){
1106
gpgme_release(mc.ctx);
1109
/* Removes the temp directory used by GPGME */
1110
if(tempdir[0] != '\0'){
1112
struct dirent *direntry;
1113
d = opendir(tempdir);
1118
direntry = readdir(d);
1119
if(direntry == NULL){
1122
if (direntry->d_type == DT_REG){
1123
char *fullname = NULL;
1124
ret = asprintf(&fullname, "%s/%s", tempdir,
1130
ret = unlink(fullname);
1132
fprintf(stderr, "unlink(\"%s\"): %s",
1133
fullname, strerror(errno));
1140
ret = rmdir(tempdir);
3100
if(signal_received){
3101
fprintf_plus(stderr, "%s exiting due to signal %d: %s\n",
3102
argv[0], signal_received,
3103
strsignal(signal_received));
3105
fprintf_plus(stderr, "%s exiting\n", argv[0]);
3109
/* Cleanup things */
3110
free(mc.interfaces);
3113
avahi_s_service_browser_free(sb);
3115
if(mc.server != NULL)
3116
avahi_server_free(mc.server);
3118
if(simple_poll != NULL)
3119
avahi_simple_poll_free(simple_poll);
3121
if(gnutls_initialized){
3122
gnutls_certificate_free_credentials(mc.cred);
3123
gnutls_dh_params_deinit(mc.dh_params);
3126
if(gpgme_initialized){
3127
gpgme_release(mc.ctx);
3130
/* Cleans up the circular linked list of Mandos servers the client
3132
if(mc.current_server != NULL){
3133
mc.current_server->prev->next = NULL;
3134
while(mc.current_server != NULL){
3135
server *next = mc.current_server->next;
3137
#pragma GCC diagnostic push
3138
#pragma GCC diagnostic ignored "-Wcast-qual"
3140
free((char *)(mc.current_server->ip));
3142
#pragma GCC diagnostic pop
3144
free(mc.current_server);
3145
mc.current_server = next;
3149
/* Re-raise privileges */
3151
ret = raise_privileges();
3154
perror_plus("Failed to raise privileges");
3157
/* Run network hooks */
3158
run_network_hooks("stop", interfaces_hooks != NULL ?
3159
interfaces_hooks : "", delay);
3161
/* Take down the network interfaces which were brought up */
3163
char *interface = NULL;
3164
while((interface = argz_next(interfaces_to_take_down,
3165
interfaces_to_take_down_size,
3167
ret = take_down_interface(interface);
3170
perror_plus("Failed to take down interface");
3173
if(debug and (interfaces_to_take_down == NULL)){
3174
fprintf_plus(stderr, "No interfaces needed to be taken"
3180
ret = lower_privileges_permanently();
3183
perror_plus("Failed to lower privileges permanently");
3187
free(interfaces_to_take_down);
3188
free(interfaces_hooks);
3190
void clean_dir_at(int base, const char * const dirname,
3192
struct dirent **direntries = NULL;
3194
int dir_fd = (int)TEMP_FAILURE_RETRY(openat(base, dirname,
3200
perror_plus("open");
3203
int numentries = scandirat(dir_fd, ".", &direntries,
3204
notdotentries, alphasort);
3205
if(numentries >= 0){
3206
for(int i = 0; i < numentries; i++){
3208
fprintf_plus(stderr, "Unlinking \"%s/%s\"\n",
3209
dirname, direntries[i]->d_name);
3211
dret = unlinkat(dir_fd, direntries[i]->d_name, 0);
3213
if(errno == EISDIR){
3214
dret = unlinkat(dir_fd, direntries[i]->d_name,
3217
if((dret == -1) and (errno == ENOTEMPTY)
3218
and (strcmp(direntries[i]->d_name, "private-keys-v1.d")
3219
== 0) and (level == 0)){
3220
/* Recurse only in this special case */
3221
clean_dir_at(dir_fd, direntries[i]->d_name, level+1);
3224
if((dret == -1) and (errno != ENOENT)){
3225
fprintf_plus(stderr, "unlink(\"%s/%s\"): %s\n", dirname,
3226
direntries[i]->d_name, strerror(errno));
3229
free(direntries[i]);
3232
/* need to clean even if 0 because man page doesn't specify */
3234
dret = unlinkat(base, dirname, AT_REMOVEDIR);
3235
if(dret == -1 and errno != ENOENT){
3236
perror_plus("rmdir");
3239
perror_plus("scandirat");
3244
/* Removes the GPGME temp directory and all files inside */
3245
if(tempdir != NULL){
3246
clean_dir_at(-1, tempdir, 0);
3250
sigemptyset(&old_sigterm_action.sa_mask);
3251
old_sigterm_action.sa_handler = SIG_DFL;
3252
ret = (int)TEMP_FAILURE_RETRY(sigaction(signal_received,
3253
&old_sigterm_action,
3256
perror_plus("sigaction");
3259
ret = raise(signal_received);
3260
} while(ret != 0 and errno == EINTR);
3262
perror_plus("raise");
3265
TEMP_FAILURE_RETRY(pause());