136
99
#define BUFFER_SIZE 256
138
#define PATHDIR "/conf/conf.d/mandos"
139
#define SECKEY "seckey.txt"
140
#define PUBKEY "pubkey.txt"
141
#define HOOKDIR "/lib/mandos/network-hooks.d"
143
101
bool debug = false;
102
static const char *keydir = "/conf/conf.d/mandos";
144
103
static const char mandos_protocol_version[] = "1";
145
const char *argp_program_version = "mandos-client " VERSION;
146
const char *argp_program_bug_address = "<mandos@recompile.se>";
147
static const char sys_class_net[] = "/sys/class/net";
148
char *connect_to = NULL;
149
const char *hookdir = HOOKDIR;
154
/* Doubly linked list that need to be circularly linked when used */
155
typedef struct server{
158
AvahiIfIndex if_index;
160
struct timespec last_seen;
104
const char *argp_program_version = "password-request 1.0";
105
const char *argp_program_bug_address = "<mandos@fukt.bsnet.se>";
165
107
/* Used for passing in values through the Avahi callback functions */
109
AvahiSimplePoll *simple_poll;
167
110
AvahiServer *server;
168
111
gnutls_certificate_credentials_t cred;
169
112
unsigned int dh_bits;
170
113
gnutls_dh_params_t dh_params;
171
114
const char *priority;
173
server *current_server;
175
size_t interfaces_size;
176
115
} mandos_context;
178
/* global so signal handler can reach it*/
179
AvahiSimplePoll *simple_poll;
181
sig_atomic_t quit_now = 0;
182
int signal_received = 0;
184
/* Function to use when printing errors */
185
void perror_plus(const char *print_text){
187
fprintf(stderr, "Mandos plugin %s: ",
188
program_invocation_short_name);
193
__attribute__((format (gnu_printf, 2, 3), nonnull))
194
int fprintf_plus(FILE *stream, const char *format, ...){
196
va_start (ap, format);
198
TEMP_FAILURE_RETRY(fprintf(stream, "Mandos plugin %s: ",
199
program_invocation_short_name));
200
return (int)TEMP_FAILURE_RETRY(vfprintf(stream, format, ap));
204
* Make additional room in "buffer" for at least BUFFER_SIZE more
205
* bytes. "buffer_capacity" is how much is currently allocated,
118
* Make room in "buffer" for at least BUFFER_SIZE additional bytes.
119
* "buffer_capacity" is how much is currently allocated,
206
120
* "buffer_length" is how much is already used.
208
__attribute__((nonnull, warn_unused_result))
209
size_t incbuffer(char **buffer, size_t buffer_length,
210
size_t buffer_capacity){
211
if(buffer_length + BUFFER_SIZE > buffer_capacity){
212
char *new_buf = realloc(*buffer, buffer_capacity + BUFFER_SIZE);
214
int old_errno = errno;
122
size_t adjustbuffer(char **buffer, size_t buffer_length,
123
size_t buffer_capacity){
124
if (buffer_length + BUFFER_SIZE > buffer_capacity){
125
*buffer = realloc(*buffer, buffer_capacity + BUFFER_SIZE);
221
129
buffer_capacity += BUFFER_SIZE;
223
131
return buffer_capacity;
226
/* Add server to set of servers to retry periodically */
227
__attribute__((nonnull, warn_unused_result))
228
bool add_server(const char *ip, in_port_t port, AvahiIfIndex if_index,
229
int af, server **current_server){
231
server *new_server = malloc(sizeof(server));
232
if(new_server == NULL){
233
perror_plus("malloc");
236
*new_server = (server){ .ip = strdup(ip),
238
.if_index = if_index,
240
if(new_server->ip == NULL){
241
perror_plus("strdup");
245
ret = clock_gettime(CLOCK_MONOTONIC, &(new_server->last_seen));
247
perror_plus("clock_gettime");
249
#pragma GCC diagnostic push
250
#pragma GCC diagnostic ignored "-Wcast-qual"
252
free((char *)(new_server->ip));
254
#pragma GCC diagnostic pop
259
/* Special case of first server */
260
if(*current_server == NULL){
261
new_server->next = new_server;
262
new_server->prev = new_server;
263
*current_server = new_server;
265
/* Place the new server last in the list */
266
new_server->next = *current_server;
267
new_server->prev = (*current_server)->prev;
268
new_server->prev->next = new_server;
269
(*current_server)->prev = new_server;
135
* Decrypt OpenPGP data using keyrings in HOMEDIR.
136
* Returns -1 on error
277
__attribute__((nonnull, warn_unused_result))
278
static bool init_gpgme(const char * const seckey,
279
const char * const pubkey,
280
const char * const tempdir,
138
static ssize_t pgp_packet_decrypt (const char *cryptotext,
141
const char *homedir){
142
gpgme_data_t dh_crypto, dh_plain;
282
144
gpgme_error_t rc;
146
size_t plaintext_capacity = 0;
147
ssize_t plaintext_length = 0;
283
148
gpgme_engine_info_t engine_info;
286
* Helper function to insert pub and seckey to the engine keyring.
288
bool import_key(const char * const filename){
291
gpgme_data_t pgp_data;
293
fd = (int)TEMP_FAILURE_RETRY(open(filename, O_RDONLY));
299
rc = gpgme_data_new_from_fd(&pgp_data, fd);
300
if(rc != GPG_ERR_NO_ERROR){
301
fprintf_plus(stderr, "bad gpgme_data_new_from_fd: %s: %s\n",
302
gpgme_strsource(rc), gpgme_strerror(rc));
306
rc = gpgme_op_import(mc->ctx, pgp_data);
307
if(rc != GPG_ERR_NO_ERROR){
308
fprintf_plus(stderr, "bad gpgme_op_import: %s: %s\n",
309
gpgme_strsource(rc), gpgme_strerror(rc));
315
perror_plus("close");
317
gpgme_data_release(pgp_data);
322
fprintf_plus(stderr, "Initializing GPGME\n");
151
fprintf(stderr, "Trying to decrypt OpenPGP data\n");
326
155
gpgme_check_version(NULL);
327
156
rc = gpgme_engine_check_version(GPGME_PROTOCOL_OpenPGP);
328
if(rc != GPG_ERR_NO_ERROR){
329
fprintf_plus(stderr, "bad gpgme_engine_check_version: %s: %s\n",
330
gpgme_strsource(rc), gpgme_strerror(rc));
157
if (rc != GPG_ERR_NO_ERROR){
158
fprintf(stderr, "bad gpgme_engine_check_version: %s: %s\n",
159
gpgme_strsource(rc), gpgme_strerror(rc));
334
163
/* Set GPGME home directory for the OpenPGP engine only */
335
rc = gpgme_get_engine_info(&engine_info);
336
if(rc != GPG_ERR_NO_ERROR){
337
fprintf_plus(stderr, "bad gpgme_get_engine_info: %s: %s\n",
338
gpgme_strsource(rc), gpgme_strerror(rc));
164
rc = gpgme_get_engine_info (&engine_info);
165
if (rc != GPG_ERR_NO_ERROR){
166
fprintf(stderr, "bad gpgme_get_engine_info: %s: %s\n",
167
gpgme_strsource(rc), gpgme_strerror(rc));
341
170
while(engine_info != NULL){
342
171
if(engine_info->protocol == GPGME_PROTOCOL_OpenPGP){
343
172
gpgme_set_engine_info(GPGME_PROTOCOL_OpenPGP,
344
engine_info->file_name, tempdir);
173
engine_info->file_name, homedir);
347
176
engine_info = engine_info->next;
349
178
if(engine_info == NULL){
350
fprintf_plus(stderr, "Could not set GPGME home dir to %s\n",
355
/* Create new GPGME "context" */
356
rc = gpgme_new(&(mc->ctx));
357
if(rc != GPG_ERR_NO_ERROR){
358
fprintf_plus(stderr, "Mandos plugin mandos-client: "
359
"bad gpgme_new: %s: %s\n", gpgme_strsource(rc),
364
if(not import_key(pubkey) or not import_key(seckey)){
372
* Decrypt OpenPGP data.
373
* Returns -1 on error
375
__attribute__((nonnull, warn_unused_result))
376
static ssize_t pgp_packet_decrypt(const char *cryptotext,
380
gpgme_data_t dh_crypto, dh_plain;
383
size_t plaintext_capacity = 0;
384
ssize_t plaintext_length = 0;
387
fprintf_plus(stderr, "Trying to decrypt OpenPGP data\n");
179
fprintf(stderr, "Could not set GPGME home dir to %s\n", homedir);
390
183
/* Create new GPGME data buffer from memory cryptotext */
391
184
rc = gpgme_data_new_from_mem(&dh_crypto, cryptotext, crypto_size,
393
if(rc != GPG_ERR_NO_ERROR){
394
fprintf_plus(stderr, "bad gpgme_data_new_from_mem: %s: %s\n",
395
gpgme_strsource(rc), gpgme_strerror(rc));
186
if (rc != GPG_ERR_NO_ERROR){
187
fprintf(stderr, "bad gpgme_data_new_from_mem: %s: %s\n",
188
gpgme_strsource(rc), gpgme_strerror(rc));
399
192
/* Create new empty GPGME data buffer for the plaintext */
400
193
rc = gpgme_data_new(&dh_plain);
401
if(rc != GPG_ERR_NO_ERROR){
402
fprintf_plus(stderr, "Mandos plugin mandos-client: "
403
"bad gpgme_data_new: %s: %s\n",
404
gpgme_strsource(rc), gpgme_strerror(rc));
194
if (rc != GPG_ERR_NO_ERROR){
195
fprintf(stderr, "bad gpgme_data_new: %s: %s\n",
196
gpgme_strsource(rc), gpgme_strerror(rc));
405
197
gpgme_data_release(dh_crypto);
201
/* Create new GPGME "context" */
202
rc = gpgme_new(&ctx);
203
if (rc != GPG_ERR_NO_ERROR){
204
fprintf(stderr, "bad gpgme_new: %s: %s\n",
205
gpgme_strsource(rc), gpgme_strerror(rc));
206
plaintext_length = -1;
409
210
/* Decrypt data from the cryptotext data buffer to the plaintext
411
rc = gpgme_op_decrypt(mc->ctx, dh_crypto, dh_plain);
412
if(rc != GPG_ERR_NO_ERROR){
413
fprintf_plus(stderr, "bad gpgme_op_decrypt: %s: %s\n",
414
gpgme_strsource(rc), gpgme_strerror(rc));
212
rc = gpgme_op_decrypt(ctx, dh_crypto, dh_plain);
213
if (rc != GPG_ERR_NO_ERROR){
214
fprintf(stderr, "bad gpgme_op_decrypt: %s: %s\n",
215
gpgme_strsource(rc), gpgme_strerror(rc));
415
216
plaintext_length = -1;
417
218
gpgme_decrypt_result_t result;
418
result = gpgme_op_decrypt_result(mc->ctx);
420
fprintf_plus(stderr, "gpgme_op_decrypt_result failed\n");
219
result = gpgme_op_decrypt_result(ctx);
221
fprintf(stderr, "gpgme_op_decrypt_result failed\n");
422
fprintf_plus(stderr, "Unsupported algorithm: %s\n",
423
result->unsupported_algorithm);
424
fprintf_plus(stderr, "Wrong key usage: %u\n",
425
result->wrong_key_usage);
223
fprintf(stderr, "Unsupported algorithm: %s\n",
224
result->unsupported_algorithm);
225
fprintf(stderr, "Wrong key usage: %u\n",
226
result->wrong_key_usage);
426
227
if(result->file_name != NULL){
427
fprintf_plus(stderr, "File name: %s\n", result->file_name);
228
fprintf(stderr, "File name: %s\n", result->file_name);
429
230
gpgme_recipient_t recipient;
430
231
recipient = result->recipients;
431
while(recipient != NULL){
432
fprintf_plus(stderr, "Public key algorithm: %s\n",
433
gpgme_pubkey_algo_name
434
(recipient->pubkey_algo));
435
fprintf_plus(stderr, "Key ID: %s\n", recipient->keyid);
436
fprintf_plus(stderr, "Secret key available: %s\n",
437
recipient->status == GPG_ERR_NO_SECKEY
439
recipient = recipient->next;
233
while(recipient != NULL){
234
fprintf(stderr, "Public key algorithm: %s\n",
235
gpgme_pubkey_algo_name(recipient->pubkey_algo));
236
fprintf(stderr, "Key ID: %s\n", recipient->keyid);
237
fprintf(stderr, "Secret key available: %s\n",
238
recipient->status == GPG_ERR_NO_SECKEY
240
recipient = recipient->next;
817
434
static void empty_log(__attribute__((unused)) AvahiLogLevel level,
818
435
__attribute__((unused)) const char *txt){}
820
/* Set effective uid to 0, return errno */
821
__attribute__((warn_unused_result))
822
int raise_privileges(void){
823
int old_errno = errno;
825
if(seteuid(0) == -1){
832
/* Set effective and real user ID to 0. Return errno. */
833
__attribute__((warn_unused_result))
834
int raise_privileges_permanently(void){
835
int old_errno = errno;
836
int ret = raise_privileges();
848
/* Set effective user ID to unprivileged saved user ID */
849
__attribute__((warn_unused_result))
850
int lower_privileges(void){
851
int old_errno = errno;
853
if(seteuid(uid) == -1){
860
/* Lower privileges permanently */
861
__attribute__((warn_unused_result))
862
int lower_privileges_permanently(void){
863
int old_errno = errno;
865
if(setuid(uid) == -1){
872
/* Helper function to add_local_route() and delete_local_route() */
873
__attribute__((nonnull, warn_unused_result))
874
static bool add_delete_local_route(const bool add,
876
AvahiIfIndex if_index){
878
char helper[] = "mandos-client-iprouteadddel";
879
char add_arg[] = "add";
880
char delete_arg[] = "delete";
881
char debug_flag[] = "--debug";
882
char *pluginhelperdir = getenv("MANDOSPLUGINHELPERDIR");
883
if(pluginhelperdir == NULL){
885
fprintf_plus(stderr, "MANDOSPLUGINHELPERDIR environment"
886
" variable not set; cannot run helper\n");
891
char interface[IF_NAMESIZE];
892
if(if_indextoname((unsigned int)if_index, interface) == NULL){
893
perror_plus("if_indextoname");
897
int devnull = (int)TEMP_FAILURE_RETRY(open("/dev/null", O_RDONLY));
899
perror_plus("open(\"/dev/null\", O_RDONLY)");
905
/* Raise privileges */
906
errno = raise_privileges_permanently();
908
perror_plus("Failed to raise privileges");
909
/* _exit(EX_NOPERM); */
915
perror_plus("setgid");
918
/* Reset supplementary groups */
920
ret = setgroups(0, NULL);
922
perror_plus("setgroups");
926
ret = dup2(devnull, STDIN_FILENO);
928
perror_plus("dup2(devnull, STDIN_FILENO)");
931
ret = close(devnull);
933
perror_plus("close");
936
ret = dup2(STDERR_FILENO, STDOUT_FILENO);
938
perror_plus("dup2(STDERR_FILENO, STDOUT_FILENO)");
941
int helperdir_fd = (int)TEMP_FAILURE_RETRY(open(pluginhelperdir,
946
if(helperdir_fd == -1){
948
_exit(EX_UNAVAILABLE);
950
int helper_fd = (int)TEMP_FAILURE_RETRY(openat(helperdir_fd,
953
perror_plus("openat");
955
_exit(EX_UNAVAILABLE);
959
#pragma GCC diagnostic push
960
#pragma GCC diagnostic ignored "-Wcast-qual"
962
if(fexecve(helper_fd, (char *const [])
963
{ helper, add ? add_arg : delete_arg, (char *)address,
964
interface, debug ? debug_flag : NULL, NULL },
967
#pragma GCC diagnostic pop
969
perror_plus("fexecve");
981
pret = waitpid(pid, &status, 0);
982
if(pret == -1 and errno == EINTR and quit_now){
983
int errno_raising = 0;
984
if((errno = raise_privileges()) != 0){
985
errno_raising = errno;
986
perror_plus("Failed to raise privileges in order to"
987
" kill helper program");
989
if(kill(pid, SIGTERM) == -1){
992
if((errno_raising == 0) and (errno = lower_privileges()) != 0){
993
perror_plus("Failed to lower privileges after killing"
998
} while(pret == -1 and errno == EINTR);
1000
perror_plus("waitpid");
1003
if(WIFEXITED(status)){
1004
if(WEXITSTATUS(status) != 0){
1005
fprintf_plus(stderr, "Error: iprouteadddel exited"
1006
" with status %d\n", WEXITSTATUS(status));
1011
if(WIFSIGNALED(status)){
1012
fprintf_plus(stderr, "Error: iprouteadddel died by"
1013
" signal %d\n", WTERMSIG(status));
1016
fprintf_plus(stderr, "Error: iprouteadddel crashed\n");
1020
__attribute__((nonnull, warn_unused_result))
1021
static bool add_local_route(const char *address,
1022
AvahiIfIndex if_index){
1024
fprintf_plus(stderr, "Adding route to %s\n", address);
1026
return add_delete_local_route(true, address, if_index);
1029
__attribute__((nonnull, warn_unused_result))
1030
static bool delete_local_route(const char *address,
1031
AvahiIfIndex if_index){
1033
fprintf_plus(stderr, "Removing route to %s\n", address);
1035
return add_delete_local_route(false, address, if_index);
1038
437
/* Called when a Mandos server is found */
1039
__attribute__((nonnull, warn_unused_result))
1040
static int start_mandos_communication(const char *ip, in_port_t port,
438
static int start_mandos_communication(const char *ip, uint16_t port,
1041
439
AvahiIfIndex if_index,
1042
int af, mandos_context *mc){
1043
int ret, tcp_sd = -1;
1045
struct sockaddr_storage to;
442
union { struct sockaddr in; struct sockaddr_in6 in6; } to;
1046
443
char *buffer = NULL;
1047
char *decrypted_buffer = NULL;
444
char *decrypted_buffer;
1048
445
size_t buffer_length = 0;
1049
446
size_t buffer_capacity = 0;
447
ssize_t decrypted_buffer_size;
450
char interface[IF_NAMESIZE];
1052
451
gnutls_session_t session;
1053
int pf; /* Protocol family */
1054
bool route_added = false;
1071
fprintf_plus(stderr, "Bad address family: %d\n", af);
1076
/* If the interface is specified and we have a list of interfaces */
1077
if(if_index != AVAHI_IF_UNSPEC and mc->interfaces != NULL){
1078
/* Check if the interface is one of the interfaces we are using */
1081
char *interface = NULL;
1082
while((interface = argz_next(mc->interfaces,
1083
mc->interfaces_size,
1085
if(if_nametoindex(interface) == (unsigned int)if_index){
1092
/* This interface does not match any in the list, so we don't
1093
connect to the server */
1095
char interface[IF_NAMESIZE];
1096
if(if_indextoname((unsigned int)if_index, interface) == NULL){
1097
perror_plus("if_indextoname");
1099
fprintf_plus(stderr, "Skipping server on non-used interface"
1101
if_indextoname((unsigned int)if_index,
453
ret = init_gnutls_session (mc, &session);
459
fprintf(stderr, "Setting up a tcp connection to %s, port %" PRIu16
463
tcp_sd = socket(PF_INET6, SOCK_STREAM, 0);
470
if(if_indextoname((unsigned int)if_index, interface) == NULL){
471
perror("if_indextoname");
474
fprintf(stderr, "Binding to interface %s\n", interface);
1109
ret = init_gnutls_session(&session, mc);
477
memset(&to, 0, sizeof(to));
478
to.in6.sin6_family = AF_INET6;
479
/* It would be nice to have a way to detect if we were passed an
480
IPv4 address here. Now we assume an IPv6 address. */
481
ret = inet_pton(AF_INET6, ip, &to.in6.sin6_addr);
1115
fprintf_plus(stderr, "Setting up a TCP connection to %s, port %"
1116
PRIuMAX "\n", ip, (uintmax_t)port);
1119
tcp_sd = socket(pf, SOCK_STREAM | SOCK_CLOEXEC, 0);
1122
perror_plus("socket");
1133
struct sockaddr_in6 *to6 = (struct sockaddr_in6 *)&to;
1134
*to6 = (struct sockaddr_in6){ .sin6_family = (sa_family_t)af };
1135
ret = inet_pton(af, ip, &to6->sin6_addr);
1137
struct sockaddr_in *to4 = (struct sockaddr_in *)&to;
1138
*to4 = (struct sockaddr_in){ .sin_family = (sa_family_t)af };
1139
ret = inet_pton(af, ip, &to4->sin_addr);
1143
perror_plus("inet_pton");
1149
fprintf_plus(stderr, "Bad address: %s\n", ip);
1154
((struct sockaddr_in6 *)&to)->sin6_port = htons(port);
1155
if(IN6_IS_ADDR_LINKLOCAL
1156
(&((struct sockaddr_in6 *)&to)->sin6_addr)){
1157
if(if_index == AVAHI_IF_UNSPEC){
1158
fprintf_plus(stderr, "An IPv6 link-local address is"
1159
" incomplete without a network interface\n");
1163
/* Set the network interface number as scope */
1164
((struct sockaddr_in6 *)&to)->sin6_scope_id = (uint32_t)if_index;
1167
((struct sockaddr_in *)&to)->sin_port = htons(port);
487
fprintf(stderr, "Bad address: %s\n", ip);
490
to.in6.sin6_port = htons(port); /* Spurious warning */
492
to.in6.sin6_scope_id = (uint32_t)if_index;
1176
if(af == AF_INET6 and if_index != AVAHI_IF_UNSPEC){
1177
char interface[IF_NAMESIZE];
1178
if(if_indextoname((unsigned int)if_index, interface) == NULL){
1179
perror_plus("if_indextoname");
1181
fprintf_plus(stderr, "Connection to: %s%%%s, port %" PRIuMAX
1182
"\n", ip, interface, (uintmax_t)port);
1185
fprintf_plus(stderr, "Connection to: %s, port %" PRIuMAX "\n",
1186
ip, (uintmax_t)port);
1188
char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?
1189
INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";
1191
ret = getnameinfo((struct sockaddr *)&to,
1192
sizeof(struct sockaddr_in6),
1193
addrstr, sizeof(addrstr), NULL, 0,
1196
ret = getnameinfo((struct sockaddr *)&to,
1197
sizeof(struct sockaddr_in),
1198
addrstr, sizeof(addrstr), NULL, 0,
1201
if(ret == EAI_SYSTEM){
1202
perror_plus("getnameinfo");
1203
} else if(ret != 0) {
1204
fprintf_plus(stderr, "getnameinfo: %s", gai_strerror(ret));
1205
} else if(strcmp(addrstr, ip) != 0){
1206
fprintf_plus(stderr, "Canonical address form: %s\n", addrstr);
1217
ret = connect(tcp_sd, (struct sockaddr *)&to,
1218
sizeof(struct sockaddr_in6));
1220
ret = connect(tcp_sd, (struct sockaddr *)&to, /* IPv4 */
1221
sizeof(struct sockaddr_in));
1224
if(((errno == ENETUNREACH) or (errno == EHOSTUNREACH))
1225
and if_index != AVAHI_IF_UNSPEC
1226
and connect_to == NULL
1227
and not route_added and
1228
((af == AF_INET6 and not
1229
IN6_IS_ADDR_LINKLOCAL(&(((struct sockaddr_in6 *)
1231
or (af == AF_INET and
1232
/* Not a a IPv4LL address */
1233
(ntohl(((struct sockaddr_in *)&to)->sin_addr.s_addr)
1234
& 0xFFFF0000L) != 0xA9FE0000L))){
1235
/* Work around Avahi bug - Avahi does not announce link-local
1236
addresses if it has a global address, so local hosts with
1237
*only* a link-local address (e.g. Mandos clients) cannot
1238
connect to a Mandos server announced by Avahi on a server
1239
host with a global address. Work around this by retrying
1240
with an explicit route added with the server's address.
1242
Avahi bug reference:
1243
https://lists.freedesktop.org/archives/avahi/2010-February/001833.html
1244
https://bugs.debian.org/587961
1247
fprintf_plus(stderr, "Mandos server unreachable, trying"
1251
route_added = add_local_route(ip, if_index);
1257
if(errno != ECONNREFUSED or debug){
1259
perror_plus("connect");
495
fprintf(stderr, "Connection to: %s, port %" PRIu16 "\n", ip,
497
char addrstr[INET6_ADDRSTRLEN] = "";
498
if(inet_ntop(to.in6.sin6_family, &(to.in6.sin6_addr), addrstr,
499
sizeof(addrstr)) == NULL){
502
if(strcmp(addrstr, ip) != 0){
503
fprintf(stderr, "Canonical address form: %s\n", addrstr);
508
ret = connect(tcp_sd, &to.in, sizeof(to));
1272
514
const char *out = mandos_protocol_version;
1275
517
size_t out_size = strlen(out);
1276
ret = (int)TEMP_FAILURE_RETRY(write(tcp_sd, out + written,
1277
out_size - written));
1280
perror_plus("write");
518
ret = TEMP_FAILURE_RETRY(write(tcp_sd, out + written,
519
out_size - written));
1282
523
goto mandos_end;
1284
525
written += (size_t)ret;
1285
526
if(written < out_size){
1288
if(out == mandos_protocol_version){
529
if (out == mandos_protocol_version){
1303
fprintf_plus(stderr, "Establishing TLS session with %s\n", ip);
1311
/* This casting via intptr_t is to eliminate warning about casting
1312
an int to a pointer type. This is exactly how the GnuTLS Guile
1313
function "set-session-transport-fd!" does it. */
1314
gnutls_transport_set_ptr(session,
1315
(gnutls_transport_ptr_t)(intptr_t)tcp_sd);
1323
ret = gnutls_handshake(session);
539
fprintf(stderr, "Establishing TLS session with %s\n", ip);
542
gnutls_transport_set_ptr (session, (gnutls_transport_ptr_t) tcp_sd);
545
ret = gnutls_handshake (session);
1328
546
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
1330
if(ret != GNUTLS_E_SUCCESS){
548
if (ret != GNUTLS_E_SUCCESS){
1332
fprintf_plus(stderr, "*** GnuTLS Handshake failed ***\n");
550
fprintf(stderr, "*** GnuTLS Handshake failed ***\n");
1336
554
goto mandos_end;
1339
557
/* Read OpenPGP packet that contains the wanted password */
1342
fprintf_plus(stderr, "Retrieving OpenPGP encrypted password from"
560
fprintf(stderr, "Retrieving pgp encrypted password from %s\n",
1353
buffer_capacity = incbuffer(&buffer, buffer_length,
1355
if(buffer_capacity == 0){
1357
perror_plus("incbuffer");
1367
sret = gnutls_record_recv(session, buffer+buffer_length,
565
buffer_capacity = adjustbuffer(&buffer, buffer_length,
567
if (buffer_capacity == 0){
568
perror("adjustbuffer");
573
ret = gnutls_record_recv(session, buffer+buffer_length,
1374
580
case GNUTLS_E_INTERRUPTED:
1375
581
case GNUTLS_E_AGAIN:
1377
583
case GNUTLS_E_REHANDSHAKE:
1379
ret = gnutls_handshake(session);
585
ret = gnutls_handshake (session);
1385
586
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
1387
fprintf_plus(stderr, "*** GnuTLS Re-handshake failed "
588
fprintf(stderr, "*** GnuTLS Re-handshake failed ***\n");
1391
591
goto mandos_end;
1395
fprintf_plus(stderr, "Unknown error while reading data from"
1396
" encrypted session with Mandos server\n");
1397
gnutls_bye(session, GNUTLS_SHUT_RDWR);
595
fprintf(stderr, "Unknown error while reading data from"
596
" encrypted session with Mandos server\n");
598
gnutls_bye (session, GNUTLS_SHUT_RDWR);
1399
599
goto mandos_end;
1402
buffer_length += (size_t) sret;
602
buffer_length += (size_t) ret;
1407
fprintf_plus(stderr, "Closing TLS session\n");
1416
ret = gnutls_bye(session, GNUTLS_SHUT_RDWR);
1421
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
1423
if(buffer_length > 0){
1424
ssize_t decrypted_buffer_size;
1425
decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,
1426
&decrypted_buffer, mc);
1427
if(decrypted_buffer_size >= 0){
607
fprintf(stderr, "Closing TLS session\n");
610
gnutls_bye (session, GNUTLS_SHUT_RDWR);
612
if (buffer_length > 0){
613
decrypted_buffer_size = pgp_packet_decrypt(buffer,
617
if (decrypted_buffer_size >= 0){
1431
619
while(written < (size_t) decrypted_buffer_size){
1437
ret = (int)fwrite(decrypted_buffer + written, 1,
1438
(size_t)decrypted_buffer_size - written,
620
ret = (int)fwrite (decrypted_buffer + written, 1,
621
(size_t)decrypted_buffer_size - written,
1440
623
if(ret == 0 and ferror(stdout)){
1443
fprintf_plus(stderr, "Error writing encrypted data: %s\n",
625
fprintf(stderr, "Error writing encrypted data: %s\n",
1449
631
written += (size_t)ret;
1451
ret = fflush(stdout);
1455
fprintf_plus(stderr, "Error writing encrypted data: %s\n",
633
free(decrypted_buffer);
1465
641
/* Shutdown procedure */
1470
if(not delete_local_route(ip, if_index)){
1471
fprintf_plus(stderr, "Failed to delete local route to %s on"
1472
" interface %d", ip, if_index);
1476
free(decrypted_buffer);
1479
ret = close(tcp_sd);
1485
perror_plus("close");
1487
gnutls_deinit(session);
646
gnutls_deinit (session);
1497
__attribute__((nonnull))
1498
650
static void resolve_callback(AvahiSServiceResolver *r,
1499
651
AvahiIfIndex interface,
1500
AvahiProtocol proto,
652
AVAHI_GCC_UNUSED AvahiProtocol protocol,
1501
653
AvahiResolverEvent event,
1502
654
const char *name,
1503
655
const char *type,
1612
738
case AVAHI_BROWSER_ALL_FOR_NOW:
1613
739
case AVAHI_BROWSER_CACHE_EXHAUSTED:
1615
fprintf_plus(stderr, "No Mandos server found, still"
741
fprintf(stderr, "No Mandos server found, still searching...\n");
1622
/* Signal handler that stops main loop after SIGTERM */
1623
static void handle_sigterm(int sig){
1628
signal_received = sig;
1629
int old_errno = errno;
1630
/* set main loop to exit */
1631
if(simple_poll != NULL){
1632
avahi_simple_poll_quit(simple_poll);
1637
__attribute__((nonnull, warn_unused_result))
1638
bool get_flags(const char *ifname, struct ifreq *ifr){
1642
int s = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1645
perror_plus("socket");
1649
strncpy(ifr->ifr_name, ifname, IF_NAMESIZE);
1650
ifr->ifr_name[IF_NAMESIZE-1] = '\0'; /* NUL terminate */
1651
ret = ioctl(s, SIOCGIFFLAGS, ifr);
1655
perror_plus("ioctl SIOCGIFFLAGS");
1663
__attribute__((nonnull, warn_unused_result))
1664
bool good_flags(const char *ifname, const struct ifreq *ifr){
1666
/* Reject the loopback device */
1667
if(ifr->ifr_flags & IFF_LOOPBACK){
1669
fprintf_plus(stderr, "Rejecting loopback interface \"%s\"\n",
1674
/* Accept point-to-point devices only if connect_to is specified */
1675
if(connect_to != NULL and (ifr->ifr_flags & IFF_POINTOPOINT)){
1677
fprintf_plus(stderr, "Accepting point-to-point interface"
1678
" \"%s\"\n", ifname);
1682
/* Otherwise, reject non-broadcast-capable devices */
1683
if(not (ifr->ifr_flags & IFF_BROADCAST)){
1685
fprintf_plus(stderr, "Rejecting non-broadcast interface"
1686
" \"%s\"\n", ifname);
1690
/* Reject non-ARP interfaces (including dummy interfaces) */
1691
if(ifr->ifr_flags & IFF_NOARP){
1693
fprintf_plus(stderr, "Rejecting non-ARP interface \"%s\"\n",
1699
/* Accept this device */
1701
fprintf_plus(stderr, "Interface \"%s\" is good\n", ifname);
1707
* This function determines if a directory entry in /sys/class/net
1708
* corresponds to an acceptable network device.
1709
* (This function is passed to scandir(3) as a filter function.)
1711
__attribute__((nonnull, warn_unused_result))
1712
int good_interface(const struct dirent *if_entry){
1713
if(if_entry->d_name[0] == '.'){
1718
if(not get_flags(if_entry->d_name, &ifr)){
1720
fprintf_plus(stderr, "Failed to get flags for interface "
1721
"\"%s\"\n", if_entry->d_name);
1726
if(not good_flags(if_entry->d_name, &ifr)){
1733
* This function determines if a network interface is up.
1735
__attribute__((nonnull, warn_unused_result))
1736
bool interface_is_up(const char *interface){
1738
if(not get_flags(interface, &ifr)){
1740
fprintf_plus(stderr, "Failed to get flags for interface "
1741
"\"%s\"\n", interface);
1746
return (bool)(ifr.ifr_flags & IFF_UP);
1750
* This function determines if a network interface is running
1752
__attribute__((nonnull, warn_unused_result))
1753
bool interface_is_running(const char *interface){
1755
if(not get_flags(interface, &ifr)){
1757
fprintf_plus(stderr, "Failed to get flags for interface "
1758
"\"%s\"\n", interface);
1763
return (bool)(ifr.ifr_flags & IFF_RUNNING);
1766
__attribute__((nonnull, pure, warn_unused_result))
1767
int notdotentries(const struct dirent *direntry){
1768
/* Skip "." and ".." */
1769
if(direntry->d_name[0] == '.'
1770
and (direntry->d_name[1] == '\0'
1771
or (direntry->d_name[1] == '.'
1772
and direntry->d_name[2] == '\0'))){
1778
/* Is this directory entry a runnable program? */
1779
__attribute__((nonnull, warn_unused_result))
1780
int runnable_hook(const struct dirent *direntry){
1785
if((direntry->d_name)[0] == '\0'){
1790
sret = strspn(direntry->d_name, "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
1791
"abcdefghijklmnopqrstuvwxyz"
1794
if((direntry->d_name)[sret] != '\0'){
1795
/* Contains non-allowed characters */
1797
fprintf_plus(stderr, "Ignoring hook \"%s\" with bad name\n",
1803
ret = fstatat(hookdir_fd, direntry->d_name, &st, 0);
1806
perror_plus("Could not stat hook");
1810
if(not (S_ISREG(st.st_mode))){
1811
/* Not a regular file */
1813
fprintf_plus(stderr, "Ignoring hook \"%s\" - not a file\n",
1818
if(not (st.st_mode & (S_IXUSR | S_IXGRP | S_IXOTH))){
1819
/* Not executable */
1821
fprintf_plus(stderr, "Ignoring hook \"%s\" - not executable\n",
1827
fprintf_plus(stderr, "Hook \"%s\" is acceptable\n",
1833
__attribute__((nonnull, warn_unused_result))
1834
int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,
1835
mandos_context *mc){
1837
struct timespec now;
1838
struct timespec waited_time;
1839
intmax_t block_time;
1842
if(mc->current_server == NULL){
1844
fprintf_plus(stderr, "Wait until first server is found."
1847
ret = avahi_simple_poll_iterate(s, -1);
1850
fprintf_plus(stderr, "Check current_server if we should run"
1853
/* the current time */
1854
ret = clock_gettime(CLOCK_MONOTONIC, &now);
1856
perror_plus("clock_gettime");
1859
/* Calculating in ms how long time between now and server
1860
who we visted longest time ago. Now - last seen. */
1861
waited_time.tv_sec = (now.tv_sec
1862
- mc->current_server->last_seen.tv_sec);
1863
waited_time.tv_nsec = (now.tv_nsec
1864
- mc->current_server->last_seen.tv_nsec);
1865
/* total time is 10s/10,000ms.
1866
Converting to s from ms by dividing by 1,000,
1867
and ns to ms by dividing by 1,000,000. */
1868
block_time = ((retry_interval
1869
- ((intmax_t)waited_time.tv_sec * 1000))
1870
- ((intmax_t)waited_time.tv_nsec / 1000000));
1873
fprintf_plus(stderr, "Blocking for %" PRIdMAX " ms\n",
1877
if(block_time <= 0){
1878
ret = start_mandos_communication(mc->current_server->ip,
1879
mc->current_server->port,
1880
mc->current_server->if_index,
1881
mc->current_server->af, mc);
1883
avahi_simple_poll_quit(s);
1886
ret = clock_gettime(CLOCK_MONOTONIC,
1887
&mc->current_server->last_seen);
1889
perror_plus("clock_gettime");
1892
mc->current_server = mc->current_server->next;
1893
block_time = 0; /* Call avahi to find new Mandos
1894
servers, but don't block */
1897
ret = avahi_simple_poll_iterate(s, (int)block_time);
1900
if(ret > 0 or errno != EINTR){
1901
return (ret != 1) ? ret : 0;
1907
__attribute__((nonnull))
1908
void run_network_hooks(const char *mode, const char *interface,
1910
struct dirent **direntries = NULL;
1911
if(hookdir_fd == -1){
1912
hookdir_fd = open(hookdir, O_RDONLY | O_DIRECTORY | O_PATH
1914
if(hookdir_fd == -1){
1915
if(errno == ENOENT){
1917
fprintf_plus(stderr, "Network hook directory \"%s\" not"
1918
" found\n", hookdir);
1921
perror_plus("open");
1926
int numhooks = scandirat(hookdir_fd, ".", &direntries,
1927
runnable_hook, alphasort);
1929
perror_plus("scandir");
1932
struct dirent *direntry;
1934
int devnull = (int)TEMP_FAILURE_RETRY(open("/dev/null", O_RDONLY));
1936
perror_plus("open(\"/dev/null\", O_RDONLY)");
1939
for(int i = 0; i < numhooks; i++){
1940
direntry = direntries[i];
1942
fprintf_plus(stderr, "Running network hook \"%s\"\n",
1945
pid_t hook_pid = fork();
1948
/* Raise privileges */
1949
errno = raise_privileges_permanently();
1951
perror_plus("Failed to raise privileges");
1958
perror_plus("setgid");
1961
/* Reset supplementary groups */
1963
ret = setgroups(0, NULL);
1965
perror_plus("setgroups");
1968
ret = setenv("MANDOSNETHOOKDIR", hookdir, 1);
1970
perror_plus("setenv");
1973
ret = setenv("DEVICE", interface, 1);
1975
perror_plus("setenv");
1978
ret = setenv("VERBOSITY", debug ? "1" : "0", 1);
1980
perror_plus("setenv");
1983
ret = setenv("MODE", mode, 1);
1985
perror_plus("setenv");
1989
ret = asprintf(&delaystring, "%f", (double)delay);
1991
perror_plus("asprintf");
1994
ret = setenv("DELAY", delaystring, 1);
1997
perror_plus("setenv");
2001
if(connect_to != NULL){
2002
ret = setenv("CONNECT", connect_to, 1);
2004
perror_plus("setenv");
2008
int hook_fd = (int)TEMP_FAILURE_RETRY(openat(hookdir_fd,
2012
perror_plus("openat");
2013
_exit(EXIT_FAILURE);
2015
if(close(hookdir_fd) == -1){
2016
perror_plus("close");
2017
_exit(EXIT_FAILURE);
2019
ret = dup2(devnull, STDIN_FILENO);
2021
perror_plus("dup2(devnull, STDIN_FILENO)");
2024
ret = close(devnull);
2026
perror_plus("close");
2029
ret = dup2(STDERR_FILENO, STDOUT_FILENO);
2031
perror_plus("dup2(STDERR_FILENO, STDOUT_FILENO)");
2034
if(fexecve(hook_fd, (char *const []){ direntry->d_name, NULL },
2036
perror_plus("fexecve");
2037
_exit(EXIT_FAILURE);
2041
perror_plus("fork");
2046
if(TEMP_FAILURE_RETRY(waitpid(hook_pid, &status, 0)) == -1){
2047
perror_plus("waitpid");
2051
if(WIFEXITED(status)){
2052
if(WEXITSTATUS(status) != 0){
2053
fprintf_plus(stderr, "Warning: network hook \"%s\" exited"
2054
" with status %d\n", direntry->d_name,
2055
WEXITSTATUS(status));
2059
} else if(WIFSIGNALED(status)){
2060
fprintf_plus(stderr, "Warning: network hook \"%s\" died by"
2061
" signal %d\n", direntry->d_name,
2066
fprintf_plus(stderr, "Warning: network hook \"%s\""
2067
" crashed\n", direntry->d_name);
2073
fprintf_plus(stderr, "Network hook \"%s\" ran successfully\n",
2079
if(close(hookdir_fd) == -1){
2080
perror_plus("close");
2087
__attribute__((nonnull, warn_unused_result))
2088
int bring_up_interface(const char *const interface,
2090
int old_errno = errno;
2092
struct ifreq network;
2093
unsigned int if_index = if_nametoindex(interface);
2095
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
2105
if(not interface_is_up(interface)){
2107
int ioctl_errno = 0;
2108
if(not get_flags(interface, &network)){
2110
fprintf_plus(stderr, "Failed to get flags for interface "
2111
"\"%s\"\n", interface);
2115
network.ifr_flags |= IFF_UP; /* set flag */
2117
int sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
2120
perror_plus("socket");
2128
perror_plus("close");
2135
fprintf_plus(stderr, "Bringing up interface \"%s\"\n",
2139
/* Raise privileges */
2140
ret_errno = raise_privileges();
2143
perror_plus("Failed to raise privileges");
2148
bool restore_loglevel = false;
2150
/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO
2151
messages about the network interface to mess up the prompt */
2152
ret_linux = klogctl(8, NULL, 5);
2153
if(ret_linux == -1){
2154
perror_plus("klogctl");
2156
restore_loglevel = true;
2159
#endif /* __linux__ */
2160
int ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
2161
ioctl_errno = errno;
2163
if(restore_loglevel){
2164
ret_linux = klogctl(7, NULL, 0);
2165
if(ret_linux == -1){
2166
perror_plus("klogctl");
2169
#endif /* __linux__ */
2171
/* If raise_privileges() succeeded above */
2173
/* Lower privileges */
2174
ret_errno = lower_privileges();
2177
perror_plus("Failed to lower privileges");
2181
/* Close the socket */
2184
perror_plus("close");
2187
if(ret_setflags == -1){
2188
errno = ioctl_errno;
2189
perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");
2194
fprintf_plus(stderr, "Interface \"%s\" is already up; good\n",
2198
/* Sleep checking until interface is running.
2199
Check every 0.25s, up to total time of delay */
2200
for(int i = 0; i < delay * 4; i++){
2201
if(interface_is_running(interface)){
2204
struct timespec sleeptime = { .tv_nsec = 250000000 };
2205
ret = nanosleep(&sleeptime, NULL);
2206
if(ret == -1 and errno != EINTR){
2207
perror_plus("nanosleep");
2215
__attribute__((nonnull, warn_unused_result))
2216
int take_down_interface(const char *const interface){
2217
int old_errno = errno;
2218
struct ifreq network;
2219
unsigned int if_index = if_nametoindex(interface);
2221
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
2225
if(interface_is_up(interface)){
2227
int ioctl_errno = 0;
2228
if(not get_flags(interface, &network) and debug){
2230
fprintf_plus(stderr, "Failed to get flags for interface "
2231
"\"%s\"\n", interface);
2235
network.ifr_flags &= ~(short)IFF_UP; /* clear flag */
2237
int sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
2240
perror_plus("socket");
2246
fprintf_plus(stderr, "Taking down interface \"%s\"\n",
2250
/* Raise privileges */
2251
ret_errno = raise_privileges();
2254
perror_plus("Failed to raise privileges");
2257
int ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
2258
ioctl_errno = errno;
2260
/* If raise_privileges() succeeded above */
2262
/* Lower privileges */
2263
ret_errno = lower_privileges();
2266
perror_plus("Failed to lower privileges");
2270
/* Close the socket */
2271
int ret = close(sd);
2273
perror_plus("close");
2276
if(ret_setflags == -1){
2277
errno = ioctl_errno;
2278
perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");
2283
fprintf_plus(stderr, "Interface \"%s\" is already down; odd\n",
747
/* Combines file name and path and returns the malloced new
748
string. some sane checks could/should be added */
749
static char *combinepath(const char *first, const char *second){
751
int ret = asprintf(&tmp, "%s/%s", first, second);
2291
759
int main(int argc, char *argv[]){
2292
mandos_context mc = { .server = NULL, .dh_bits = 0,
2293
.priority = "SECURE256:!CTYPE-X.509"
2294
":+CTYPE-OPENPGP:!RSA:+SIGN-DSA-SHA256",
2295
.current_server = NULL, .interfaces = NULL,
2296
.interfaces_size = 0 };
2297
AvahiSServiceBrowser *sb = NULL;
2302
int exitcode = EXIT_SUCCESS;
2303
char *interfaces_to_take_down = NULL;
2304
size_t interfaces_to_take_down_size = 0;
2305
char run_tempdir[] = "/run/tmp/mandosXXXXXX";
2306
char old_tempdir[] = "/tmp/mandosXXXXXX";
2307
char *tempdir = NULL;
2308
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
2309
const char *seckey = PATHDIR "/" SECKEY;
2310
const char *pubkey = PATHDIR "/" PUBKEY;
2311
const char *dh_params_file = NULL;
2312
char *interfaces_hooks = NULL;
2314
bool gnutls_initialized = false;
2315
bool gpgme_initialized = false;
2317
double retry_interval = 10; /* 10s between trying a server and
2318
retrying the same server again */
2320
struct sigaction old_sigterm_action = { .sa_handler = SIG_DFL };
2321
struct sigaction sigterm_action = { .sa_handler = handle_sigterm };
2326
/* Lower any group privileges we might have, just to be safe */
2330
perror_plus("setgid");
2333
/* Lower user privileges (temporarily) */
2337
perror_plus("seteuid");
2345
struct argp_option options[] = {
2346
{ .name = "debug", .key = 128,
2347
.doc = "Debug mode", .group = 3 },
2348
{ .name = "connect", .key = 'c',
2349
.arg = "ADDRESS:PORT",
2350
.doc = "Connect directly to a specific Mandos server",
2352
{ .name = "interface", .key = 'i',
2354
.doc = "Network interface that will be used to search for"
2357
{ .name = "seckey", .key = 's',
2359
.doc = "OpenPGP secret key file base name",
2361
{ .name = "pubkey", .key = 'p',
2363
.doc = "OpenPGP public key file base name",
2365
{ .name = "dh-bits", .key = 129,
2367
.doc = "Bit length of the prime number used in the"
2368
" Diffie-Hellman key exchange",
2370
{ .name = "dh-params", .key = 134,
2372
.doc = "PEM-encoded PKCS#3 file with pre-generated parameters"
2373
" for the Diffie-Hellman key exchange",
2375
{ .name = "priority", .key = 130,
2377
.doc = "GnuTLS priority string for the TLS handshake",
2379
{ .name = "delay", .key = 131,
2381
.doc = "Maximum delay to wait for interface startup",
2383
{ .name = "retry", .key = 132,
2385
.doc = "Retry interval used when denied by the Mandos server",
2387
{ .name = "network-hook-dir", .key = 133,
2389
.doc = "Directory where network hooks are located",
2392
* These reproduce what we would get without ARGP_NO_HELP
2394
{ .name = "help", .key = '?',
2395
.doc = "Give this help list", .group = -1 },
2396
{ .name = "usage", .key = -3,
2397
.doc = "Give a short usage message", .group = -1 },
2398
{ .name = "version", .key = 'V',
2399
.doc = "Print program version", .group = -1 },
2403
error_t parse_opt(int key, char *arg,
2404
struct argp_state *state){
760
AvahiSServiceBrowser *sb = NULL;
763
int exitcode = EXIT_SUCCESS;
764
const char *interface = "eth0";
765
struct ifreq network;
769
char *connect_to = NULL;
770
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
771
char *pubkeyfilename = NULL;
772
char *seckeyfilename = NULL;
773
const char *pubkeyname = "pubkey.txt";
774
const char *seckeyname = "seckey.txt";
775
mandos_context mc = { .simple_poll = NULL, .server = NULL,
776
.dh_bits = 1024, .priority = "SECURE256"
777
":!CTYPE-X.509:+CTYPE-OPENPGP" };
778
bool gnutls_initalized = false;
781
struct argp_option options[] = {
782
{ .name = "debug", .key = 128,
783
.doc = "Debug mode", .group = 3 },
784
{ .name = "connect", .key = 'c',
785
.arg = "ADDRESS:PORT",
786
.doc = "Connect directly to a specific Mandos server",
788
{ .name = "interface", .key = 'i',
790
.doc = "Interface that will be used to search for Mandos"
793
{ .name = "keydir", .key = 'd',
795
.doc = "Directory to read the OpenPGP key files from",
797
{ .name = "seckey", .key = 's',
799
.doc = "OpenPGP secret key file base name",
801
{ .name = "pubkey", .key = 'p',
803
.doc = "OpenPGP public key file base name",
805
{ .name = "dh-bits", .key = 129,
807
.doc = "Bit length of the prime number used in the"
808
" Diffie-Hellman key exchange",
810
{ .name = "priority", .key = 130,
812
.doc = "GnuTLS priority string for the TLS handshake",
817
error_t parse_opt (int key, char *arg,
818
struct argp_state *state) {
819
/* Get the INPUT argument from `argp_parse', which we know is
820
a pointer to our plugin list pointer. */
822
case 128: /* --debug */
825
case 'c': /* --connect */
828
case 'i': /* --interface */
831
case 'd': /* --keydir */
834
case 's': /* --seckey */
837
case 'p': /* --pubkey */
840
case 129: /* --dh-bits */
842
mc.dh_bits = (unsigned int) strtol(arg, NULL, 10);
848
case 130: /* --priority */
856
return ARGP_ERR_UNKNOWN;
861
struct argp argp = { .options = options, .parser = parse_opt,
863
.doc = "Mandos client -- Get and decrypt"
864
" passwords from a Mandos server" };
865
ret = argp_parse (&argp, argc, argv, 0, 0, NULL);
866
if (ret == ARGP_ERR_UNKNOWN){
867
fprintf(stderr, "Unknown error while parsing arguments\n");
868
exitcode = EXIT_FAILURE;
873
pubkeyfilename = combinepath(keydir, pubkeyname);
874
if (pubkeyfilename == NULL){
875
perror("combinepath");
876
exitcode = EXIT_FAILURE;
880
seckeyfilename = combinepath(keydir, seckeyname);
881
if (seckeyfilename == NULL){
882
perror("combinepath");
883
exitcode = EXIT_FAILURE;
887
ret = init_gnutls_global(&mc, pubkeyfilename, seckeyfilename);
889
fprintf(stderr, "init_gnutls_global failed\n");
890
exitcode = EXIT_FAILURE;
893
gnutls_initalized = true;
896
/* If the interface is down, bring it up */
898
sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
901
exitcode = EXIT_FAILURE;
904
strcpy(network.ifr_name, interface);
905
ret = ioctl(sd, SIOCGIFFLAGS, &network);
907
perror("ioctl SIOCGIFFLAGS");
908
exitcode = EXIT_FAILURE;
911
if((network.ifr_flags & IFF_UP) == 0){
912
network.ifr_flags |= IFF_UP;
913
ret = ioctl(sd, SIOCSIFFLAGS, &network);
915
perror("ioctl SIOCSIFFLAGS");
916
exitcode = EXIT_FAILURE;
936
if_index = (AvahiIfIndex) if_nametoindex(interface);
938
fprintf(stderr, "No such interface: \"%s\"\n", interface);
942
if(connect_to != NULL){
943
/* Connect directly, do not use Zeroconf */
944
/* (Mainly meant for debugging) */
945
char *address = strrchr(connect_to, ':');
947
fprintf(stderr, "No colon in address\n");
948
exitcode = EXIT_FAILURE;
2407
case 128: /* --debug */
2410
case 'c': /* --connect */
2413
case 'i': /* --interface */
2414
ret_errno = argz_add_sep(&mc.interfaces, &mc.interfaces_size,
2417
argp_error(state, "%s", strerror(ret_errno));
2420
case 's': /* --seckey */
2423
case 'p': /* --pubkey */
2426
case 129: /* --dh-bits */
2428
tmpmax = strtoimax(arg, &tmp, 10);
2429
if(errno != 0 or tmp == arg or *tmp != '\0'
2430
or tmpmax != (typeof(mc.dh_bits))tmpmax){
2431
argp_error(state, "Bad number of DH bits");
2433
mc.dh_bits = (typeof(mc.dh_bits))tmpmax;
2435
case 134: /* --dh-params */
2436
dh_params_file = arg;
2438
case 130: /* --priority */
2441
case 131: /* --delay */
2443
delay = strtof(arg, &tmp);
2444
if(errno != 0 or tmp == arg or *tmp != '\0'){
2445
argp_error(state, "Bad delay");
2447
case 132: /* --retry */
2449
retry_interval = strtod(arg, &tmp);
2450
if(errno != 0 or tmp == arg or *tmp != '\0'
2451
or (retry_interval * 1000) > INT_MAX
2452
or retry_interval < 0){
2453
argp_error(state, "Bad retry interval");
2456
case 133: /* --network-hook-dir */
2460
* These reproduce what we would get without ARGP_NO_HELP
2462
case '?': /* --help */
2463
argp_state_help(state, state->out_stream,
2464
(ARGP_HELP_STD_HELP | ARGP_HELP_EXIT_ERR)
2465
& ~(unsigned int)ARGP_HELP_EXIT_OK);
2466
case -3: /* --usage */
2467
argp_state_help(state, state->out_stream,
2468
ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);
2469
case 'V': /* --version */
2470
fprintf_plus(state->out_stream, "%s\n", argp_program_version);
2471
exit(argp_err_exit_status);
2474
return ARGP_ERR_UNKNOWN;
2479
struct argp argp = { .options = options, .parser = parse_opt,
2481
.doc = "Mandos client -- Get and decrypt"
2482
" passwords from a Mandos server" };
2483
ret_errno = argp_parse(&argp, argc, argv,
2484
ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);
2491
perror_plus("argp_parse");
2492
exitcode = EX_OSERR;
2495
exitcode = EX_USAGE;
2501
/* Work around Debian bug #633582:
2502
<https://bugs.debian.org/633582> */
2504
/* Re-raise privileges */
2505
ret = raise_privileges();
2508
perror_plus("Failed to raise privileges");
2512
if(strcmp(seckey, PATHDIR "/" SECKEY) == 0){
2513
int seckey_fd = open(seckey, O_RDONLY);
2514
if(seckey_fd == -1){
2515
perror_plus("open");
2517
ret = (int)TEMP_FAILURE_RETRY(fstat(seckey_fd, &st));
2519
perror_plus("fstat");
2521
if(S_ISREG(st.st_mode)
2522
and st.st_uid == 0 and st.st_gid == 0){
2523
ret = fchown(seckey_fd, uid, gid);
2525
perror_plus("fchown");
2533
if(strcmp(pubkey, PATHDIR "/" PUBKEY) == 0){
2534
int pubkey_fd = open(pubkey, O_RDONLY);
2535
if(pubkey_fd == -1){
2536
perror_plus("open");
2538
ret = (int)TEMP_FAILURE_RETRY(fstat(pubkey_fd, &st));
2540
perror_plus("fstat");
2542
if(S_ISREG(st.st_mode)
2543
and st.st_uid == 0 and st.st_gid == 0){
2544
ret = fchown(pubkey_fd, uid, gid);
2546
perror_plus("fchown");
2554
if(dh_params_file != NULL
2555
and strcmp(dh_params_file, PATHDIR "/dhparams.pem" ) == 0){
2556
int dhparams_fd = open(dh_params_file, O_RDONLY);
2557
if(dhparams_fd == -1){
2558
perror_plus("open");
2560
ret = (int)TEMP_FAILURE_RETRY(fstat(dhparams_fd, &st));
2562
perror_plus("fstat");
2564
if(S_ISREG(st.st_mode)
2565
and st.st_uid == 0 and st.st_gid == 0){
2566
ret = fchown(dhparams_fd, uid, gid);
2568
perror_plus("fchown");
2576
/* Lower privileges */
2577
ret = lower_privileges();
2580
perror_plus("Failed to lower privileges");
2585
/* Remove invalid interface names (except "none") */
2587
char *interface = NULL;
2588
while((interface = argz_next(mc.interfaces, mc.interfaces_size,
2590
if(strcmp(interface, "none") != 0
2591
and if_nametoindex(interface) == 0){
2592
if(interface[0] != '\0'){
2593
fprintf_plus(stderr, "Not using nonexisting interface"
2594
" \"%s\"\n", interface);
2596
argz_delete(&mc.interfaces, &mc.interfaces_size, interface);
2602
/* Run network hooks */
2604
if(mc.interfaces != NULL){
2605
interfaces_hooks = malloc(mc.interfaces_size);
2606
if(interfaces_hooks == NULL){
2607
perror_plus("malloc");
952
uint16_t port = (uint16_t) strtol(address+1, NULL, 10);
954
perror("Bad port number");
955
exitcode = EXIT_FAILURE;
2610
memcpy(interfaces_hooks, mc.interfaces, mc.interfaces_size);
2611
argz_stringify(interfaces_hooks, mc.interfaces_size, (int)',');
2613
run_network_hooks("start", interfaces_hooks != NULL ?
2614
interfaces_hooks : "", delay);
2618
avahi_set_log_function(empty_log);
2621
/* Initialize Avahi early so avahi_simple_poll_quit() can be called
2622
from the signal handler */
2623
/* Initialize the pseudo-RNG for Avahi */
2624
srand((unsigned int) time(NULL));
2625
simple_poll = avahi_simple_poll_new();
2626
if(simple_poll == NULL){
2627
fprintf_plus(stderr,
2628
"Avahi: Failed to create simple poll object.\n");
2629
exitcode = EX_UNAVAILABLE;
2633
sigemptyset(&sigterm_action.sa_mask);
2634
ret = sigaddset(&sigterm_action.sa_mask, SIGINT);
2636
perror_plus("sigaddset");
2637
exitcode = EX_OSERR;
2640
ret = sigaddset(&sigterm_action.sa_mask, SIGHUP);
2642
perror_plus("sigaddset");
2643
exitcode = EX_OSERR;
2646
ret = sigaddset(&sigterm_action.sa_mask, SIGTERM);
2648
perror_plus("sigaddset");
2649
exitcode = EX_OSERR;
2652
/* Need to check if the handler is SIG_IGN before handling:
2653
| [[info:libc:Initial Signal Actions]] |
2654
| [[info:libc:Basic Signal Handling]] |
2656
ret = sigaction(SIGINT, NULL, &old_sigterm_action);
2658
perror_plus("sigaction");
2661
if(old_sigterm_action.sa_handler != SIG_IGN){
2662
ret = sigaction(SIGINT, &sigterm_action, NULL);
2664
perror_plus("sigaction");
2665
exitcode = EX_OSERR;
2669
ret = sigaction(SIGHUP, NULL, &old_sigterm_action);
2671
perror_plus("sigaction");
2674
if(old_sigterm_action.sa_handler != SIG_IGN){
2675
ret = sigaction(SIGHUP, &sigterm_action, NULL);
2677
perror_plus("sigaction");
2678
exitcode = EX_OSERR;
2682
ret = sigaction(SIGTERM, NULL, &old_sigterm_action);
2684
perror_plus("sigaction");
2687
if(old_sigterm_action.sa_handler != SIG_IGN){
2688
ret = sigaction(SIGTERM, &sigterm_action, NULL);
2690
perror_plus("sigaction");
2691
exitcode = EX_OSERR;
2696
/* If no interfaces were specified, make a list */
2697
if(mc.interfaces == NULL){
2698
struct dirent **direntries = NULL;
2699
/* Look for any good interfaces */
2700
ret = scandir(sys_class_net, &direntries, good_interface,
2703
/* Add all found interfaces to interfaces list */
2704
for(int i = 0; i < ret; ++i){
2705
ret_errno = argz_add(&mc.interfaces, &mc.interfaces_size,
2706
direntries[i]->d_name);
2709
perror_plus("argz_add");
2710
free(direntries[i]);
2714
fprintf_plus(stderr, "Will use interface \"%s\"\n",
2715
direntries[i]->d_name);
2717
free(direntries[i]);
2724
fprintf_plus(stderr, "Could not find a network interface\n");
2725
exitcode = EXIT_FAILURE;
2730
/* Bring up interfaces which are down, and remove any "none"s */
2732
char *interface = NULL;
2733
while((interface = argz_next(mc.interfaces, mc.interfaces_size,
2735
/* If interface name is "none", stop bringing up interfaces.
2736
Also remove all instances of "none" from the list */
2737
if(strcmp(interface, "none") == 0){
2738
argz_delete(&mc.interfaces, &mc.interfaces_size,
2741
while((interface = argz_next(mc.interfaces,
2742
mc.interfaces_size, interface))){
2743
if(strcmp(interface, "none") == 0){
2744
argz_delete(&mc.interfaces, &mc.interfaces_size,
2751
bool interface_was_up = interface_is_up(interface);
2752
errno = bring_up_interface(interface, delay);
2753
if(not interface_was_up){
2755
fprintf_plus(stderr, "Failed to bring up interface \"%s\":"
2756
" %s\n", interface, strerror(errno));
2758
errno = argz_add(&interfaces_to_take_down,
2759
&interfaces_to_take_down_size,
2762
perror_plus("argz_add");
2767
if(debug and (interfaces_to_take_down == NULL)){
2768
fprintf_plus(stderr, "No interfaces were brought up\n");
2772
/* If we only got one interface, explicitly use only that one */
2773
if(argz_count(mc.interfaces, mc.interfaces_size) == 1){
2775
fprintf_plus(stderr, "Using only interface \"%s\"\n",
2778
if_index = (AvahiIfIndex)if_nametoindex(mc.interfaces);
2785
ret = init_gnutls_global(pubkey, seckey, dh_params_file, &mc);
2787
fprintf_plus(stderr, "init_gnutls_global failed\n");
2788
exitcode = EX_UNAVAILABLE;
2791
gnutls_initialized = true;
2798
/* Try /run/tmp before /tmp */
2799
tempdir = mkdtemp(run_tempdir);
2800
if(tempdir == NULL and errno == ENOENT){
2802
fprintf_plus(stderr, "Tempdir %s did not work, trying %s\n",
2803
run_tempdir, old_tempdir);
2805
tempdir = mkdtemp(old_tempdir);
2807
if(tempdir == NULL){
2808
perror_plus("mkdtemp");
2816
if(not init_gpgme(pubkey, seckey, tempdir, &mc)){
2817
fprintf_plus(stderr, "init_gpgme failed\n");
2818
exitcode = EX_UNAVAILABLE;
2821
gpgme_initialized = true;
2828
if(connect_to != NULL){
2829
/* Connect directly, do not use Zeroconf */
2830
/* (Mainly meant for debugging) */
2831
char *address = strrchr(connect_to, ':');
2833
if(address == NULL){
2834
fprintf_plus(stderr, "No colon in address\n");
2835
exitcode = EX_USAGE;
2845
tmpmax = strtoimax(address+1, &tmp, 10);
2846
if(errno != 0 or tmp == address+1 or *tmp != '\0'
2847
or tmpmax != (in_port_t)tmpmax){
2848
fprintf_plus(stderr, "Bad port number\n");
2849
exitcode = EX_USAGE;
2857
port = (in_port_t)tmpmax;
2859
/* Colon in address indicates IPv6 */
2861
if(strchr(connect_to, ':') != NULL){
2863
/* Accept [] around IPv6 address - see RFC 5952 */
2864
if(connect_to[0] == '[' and address[-1] == ']')
2872
address = connect_to;
2878
while(not quit_now){
2879
ret = start_mandos_communication(address, port, if_index, af,
2881
if(quit_now or ret == 0){
2885
fprintf_plus(stderr, "Retrying in %d seconds\n",
2886
(int)retry_interval);
2888
sleep((unsigned int)retry_interval);
2892
exitcode = EXIT_SUCCESS;
2903
AvahiServerConfig config;
2904
/* Do not publish any local Zeroconf records */
2905
avahi_server_config_init(&config);
2906
config.publish_hinfo = 0;
2907
config.publish_addresses = 0;
2908
config.publish_workstation = 0;
2909
config.publish_domain = 0;
2911
/* Allocate a new server */
2912
mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),
2913
&config, NULL, NULL, &ret);
2915
/* Free the Avahi configuration data */
2916
avahi_server_config_free(&config);
2919
/* Check if creating the Avahi server object succeeded */
2920
if(mc.server == NULL){
2921
fprintf_plus(stderr, "Failed to create Avahi server: %s\n",
2922
avahi_strerror(ret));
2923
exitcode = EX_UNAVAILABLE;
2931
/* Create the Avahi service browser */
2932
sb = avahi_s_service_browser_new(mc.server, if_index,
2933
AVAHI_PROTO_UNSPEC, "_mandos._tcp",
2934
NULL, 0, browse_callback,
2937
fprintf_plus(stderr, "Failed to create service browser: %s\n",
2938
avahi_strerror(avahi_server_errno(mc.server)));
2939
exitcode = EX_UNAVAILABLE;
2947
/* Run the main loop */
2950
fprintf_plus(stderr, "Starting Avahi loop search\n");
2953
ret = avahi_loop_with_timeout(simple_poll,
2954
(int)(retry_interval * 1000), &mc);
2956
fprintf_plus(stderr, "avahi_loop_with_timeout exited %s\n",
2957
(ret == 0) ? "successfully" : "with error");
959
address = connect_to;
960
ret = start_mandos_communication(address, port, if_index, &mc);
962
exitcode = EXIT_FAILURE;
964
exitcode = EXIT_SUCCESS;
970
avahi_set_log_function(empty_log);
973
/* Initialize the pseudo-RNG for Avahi */
974
srand((unsigned int) time(NULL));
976
/* Allocate main Avahi loop object */
977
mc.simple_poll = avahi_simple_poll_new();
978
if (mc.simple_poll == NULL) {
979
fprintf(stderr, "Avahi: Failed to create simple poll"
981
exitcode = EXIT_FAILURE;
986
AvahiServerConfig config;
987
/* Do not publish any local Zeroconf records */
988
avahi_server_config_init(&config);
989
config.publish_hinfo = 0;
990
config.publish_addresses = 0;
991
config.publish_workstation = 0;
992
config.publish_domain = 0;
994
/* Allocate a new server */
995
mc.server = avahi_server_new(avahi_simple_poll_get
996
(mc.simple_poll), &config, NULL,
999
/* Free the Avahi configuration data */
1000
avahi_server_config_free(&config);
1003
/* Check if creating the Avahi server object succeeded */
1004
if (mc.server == NULL) {
1005
fprintf(stderr, "Failed to create Avahi server: %s\n",
1006
avahi_strerror(error));
1007
exitcode = EXIT_FAILURE;
1011
/* Create the Avahi service browser */
1012
sb = avahi_s_service_browser_new(mc.server, if_index,
1014
"_mandos._tcp", NULL, 0,
1015
browse_callback, &mc);
1017
fprintf(stderr, "Failed to create service browser: %s\n",
1018
avahi_strerror(avahi_server_errno(mc.server)));
1019
exitcode = EXIT_FAILURE;
1023
/* Run the main loop */
1026
fprintf(stderr, "Starting Avahi loop search\n");
1029
avahi_simple_poll_loop(mc.simple_poll);
2963
if(signal_received){
2964
fprintf_plus(stderr, "%s exiting due to signal %d: %s\n",
2965
argv[0], signal_received,
2966
strsignal(signal_received));
2968
fprintf_plus(stderr, "%s exiting\n", argv[0]);
2972
/* Cleanup things */
2973
free(mc.interfaces);
2976
avahi_s_service_browser_free(sb);
2978
if(mc.server != NULL)
2979
avahi_server_free(mc.server);
2981
if(simple_poll != NULL)
2982
avahi_simple_poll_free(simple_poll);
2984
if(gnutls_initialized){
2985
gnutls_certificate_free_credentials(mc.cred);
2986
gnutls_dh_params_deinit(mc.dh_params);
2989
if(gpgme_initialized){
2990
gpgme_release(mc.ctx);
2993
/* Cleans up the circular linked list of Mandos servers the client
2995
if(mc.current_server != NULL){
2996
mc.current_server->prev->next = NULL;
2997
while(mc.current_server != NULL){
2998
server *next = mc.current_server->next;
3000
#pragma GCC diagnostic push
3001
#pragma GCC diagnostic ignored "-Wcast-qual"
3003
free((char *)(mc.current_server->ip));
3005
#pragma GCC diagnostic pop
3007
free(mc.current_server);
3008
mc.current_server = next;
3012
/* Re-raise privileges */
3014
ret = raise_privileges();
3017
perror_plus("Failed to raise privileges");
3020
/* Run network hooks */
3021
run_network_hooks("stop", interfaces_hooks != NULL ?
3022
interfaces_hooks : "", delay);
3024
/* Take down the network interfaces which were brought up */
3026
char *interface = NULL;
3027
while((interface = argz_next(interfaces_to_take_down,
3028
interfaces_to_take_down_size,
3030
ret = take_down_interface(interface);
3033
perror_plus("Failed to take down interface");
3036
if(debug and (interfaces_to_take_down == NULL)){
3037
fprintf_plus(stderr, "No interfaces needed to be taken"
3043
ret = lower_privileges_permanently();
3046
perror_plus("Failed to lower privileges permanently");
3050
free(interfaces_to_take_down);
3051
free(interfaces_hooks);
3053
void clean_dir_at(int base, const char * const dirname,
3055
struct dirent **direntries = NULL;
3057
int dir_fd = (int)TEMP_FAILURE_RETRY(openat(base, dirname,
3063
perror_plus("open");
3065
int numentries = scandirat(dir_fd, ".", &direntries,
3066
notdotentries, alphasort);
3067
if(numentries >= 0){
3068
for(int i = 0; i < numentries; i++){
3070
fprintf_plus(stderr, "Unlinking \"%s/%s\"\n",
3071
dirname, direntries[i]->d_name);
3073
dret = unlinkat(dir_fd, direntries[i]->d_name, 0);
3075
if(errno == EISDIR){
3076
dret = unlinkat(dir_fd, direntries[i]->d_name,
3079
if((dret == -1) and (errno == ENOTEMPTY)
3080
and (strcmp(direntries[i]->d_name, "private-keys-v1.d")
3081
== 0) and (level == 0)){
3082
/* Recurse only in this special case */
3083
clean_dir_at(dir_fd, direntries[i]->d_name, level+1);
3087
fprintf_plus(stderr, "unlink(\"%s/%s\"): %s\n", dirname,
3088
direntries[i]->d_name, strerror(errno));
3091
free(direntries[i]);
3094
/* need to clean even if 0 because man page doesn't specify */
3096
if(numentries == -1){
3097
perror_plus("scandirat");
3099
dret = unlinkat(base, dirname, AT_REMOVEDIR);
3100
if(dret == -1 and errno != ENOENT){
3101
perror_plus("rmdir");
3104
perror_plus("scandirat");
3109
/* Removes the GPGME temp directory and all files inside */
3110
if(tempdir != NULL){
3111
clean_dir_at(-1, tempdir, 0);
3115
sigemptyset(&old_sigterm_action.sa_mask);
3116
old_sigterm_action.sa_handler = SIG_DFL;
3117
ret = (int)TEMP_FAILURE_RETRY(sigaction(signal_received,
3118
&old_sigterm_action,
3121
perror_plus("sigaction");
3124
ret = raise(signal_received);
3125
} while(ret != 0 and errno == EINTR);
3127
perror_plus("raise");
3130
TEMP_FAILURE_RETRY(pause());
1034
fprintf(stderr, "%s exiting\n", argv[0]);
1037
/* Cleanup things */
1039
avahi_s_service_browser_free(sb);
1041
if (mc.server != NULL)
1042
avahi_server_free(mc.server);
1044
if (mc.simple_poll != NULL)
1045
avahi_simple_poll_free(mc.simple_poll);
1046
free(pubkeyfilename);
1047
free(seckeyfilename);
1049
if (gnutls_initalized){
1050
gnutls_certificate_free_credentials(mc.cred);
1051
gnutls_global_deinit ();