137
99
#define BUFFER_SIZE 256
139
#define PATHDIR "/conf/conf.d/mandos"
140
#define SECKEY "seckey.txt"
141
#define PUBKEY "pubkey.txt"
142
#define HOOKDIR "/lib/mandos/network-hooks.d"
144
101
bool debug = false;
102
static const char *keydir = "/conf/conf.d/mandos";
145
103
static const char mandos_protocol_version[] = "1";
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;
104
const char *argp_program_version = "password-request 1.0";
105
const char *argp_program_bug_address = "<mandos@fukt.bsnet.se>";
166
107
/* Used for passing in values through the Avahi callback functions */
109
AvahiSimplePoll *simple_poll;
168
110
AvahiServer *server;
169
111
gnutls_certificate_credentials_t cred;
170
112
unsigned int dh_bits;
171
113
gnutls_dh_params_t dh_params;
172
114
const char *priority;
174
server *current_server;
176
size_t interfaces_size;
177
115
} 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));
205
* Make additional room in "buffer" for at least BUFFER_SIZE more
206
* 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,
207
120
* "buffer_length" is how much is already used.
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;
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);
222
129
buffer_capacity += BUFFER_SIZE;
224
131
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;
135
* Decrypt OpenPGP data using keyrings in HOMEDIR.
136
* Returns -1 on error
278
__attribute__((nonnull, warn_unused_result))
279
static bool init_gpgme(const char * const seckey,
280
const char * const pubkey,
281
const char * const tempdir,
138
static ssize_t pgp_packet_decrypt (const char *cryptotext,
141
const char *homedir){
142
gpgme_data_t dh_crypto, dh_plain;
283
144
gpgme_error_t rc;
146
size_t plaintext_capacity = 0;
147
ssize_t plaintext_length = 0;
284
148
gpgme_engine_info_t engine_info;
287
* Helper function to insert pub and seckey to the engine keyring.
289
bool import_key(const char * const filename){
292
gpgme_data_t pgp_data;
294
fd = (int)TEMP_FAILURE_RETRY(open(filename, O_RDONLY));
300
rc = gpgme_data_new_from_fd(&pgp_data, fd);
301
if(rc != GPG_ERR_NO_ERROR){
302
fprintf_plus(stderr, "bad gpgme_data_new_from_fd: %s: %s\n",
303
gpgme_strsource(rc), gpgme_strerror(rc));
307
rc = gpgme_op_import(mc->ctx, pgp_data);
308
if(rc != GPG_ERR_NO_ERROR){
309
fprintf_plus(stderr, "bad gpgme_op_import: %s: %s\n",
310
gpgme_strsource(rc), gpgme_strerror(rc));
316
perror_plus("close");
318
gpgme_data_release(pgp_data);
323
fprintf_plus(stderr, "Initializing GPGME\n");
151
fprintf(stderr, "Trying to decrypt OpenPGP data\n");
327
155
gpgme_check_version(NULL);
328
156
rc = gpgme_engine_check_version(GPGME_PROTOCOL_OpenPGP);
329
if(rc != GPG_ERR_NO_ERROR){
330
fprintf_plus(stderr, "bad gpgme_engine_check_version: %s: %s\n",
331
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));
335
163
/* Set GPGME home directory for the OpenPGP engine only */
336
rc = gpgme_get_engine_info(&engine_info);
337
if(rc != GPG_ERR_NO_ERROR){
338
fprintf_plus(stderr, "bad gpgme_get_engine_info: %s: %s\n",
339
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));
342
170
while(engine_info != NULL){
343
171
if(engine_info->protocol == GPGME_PROTOCOL_OpenPGP){
344
172
gpgme_set_engine_info(GPGME_PROTOCOL_OpenPGP,
345
engine_info->file_name, tempdir);
173
engine_info->file_name, homedir);
348
176
engine_info = engine_info->next;
350
178
if(engine_info == NULL){
351
fprintf_plus(stderr, "Could not set GPGME home dir to %s\n",
356
/* Create new GPGME "context" */
357
rc = gpgme_new(&(mc->ctx));
358
if(rc != GPG_ERR_NO_ERROR){
359
fprintf_plus(stderr, "Mandos plugin mandos-client: "
360
"bad gpgme_new: %s: %s\n", gpgme_strsource(rc),
365
if(not import_key(pubkey) or not import_key(seckey)){
373
* Decrypt OpenPGP data.
374
* Returns -1 on error
376
__attribute__((nonnull, warn_unused_result))
377
static ssize_t pgp_packet_decrypt(const char *cryptotext,
381
gpgme_data_t dh_crypto, dh_plain;
384
size_t plaintext_capacity = 0;
385
ssize_t plaintext_length = 0;
388
fprintf_plus(stderr, "Trying to decrypt OpenPGP data\n");
179
fprintf(stderr, "Could not set GPGME home dir to %s\n", homedir);
391
183
/* Create new GPGME data buffer from memory cryptotext */
392
184
rc = gpgme_data_new_from_mem(&dh_crypto, cryptotext, crypto_size,
394
if(rc != GPG_ERR_NO_ERROR){
395
fprintf_plus(stderr, "bad gpgme_data_new_from_mem: %s: %s\n",
396
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));
400
192
/* Create new empty GPGME data buffer for the plaintext */
401
193
rc = gpgme_data_new(&dh_plain);
402
if(rc != GPG_ERR_NO_ERROR){
403
fprintf_plus(stderr, "Mandos plugin mandos-client: "
404
"bad gpgme_data_new: %s: %s\n",
405
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));
406
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;
410
210
/* Decrypt data from the cryptotext data buffer to the plaintext
412
rc = gpgme_op_decrypt(mc->ctx, dh_crypto, dh_plain);
413
if(rc != GPG_ERR_NO_ERROR){
414
fprintf_plus(stderr, "bad gpgme_op_decrypt: %s: %s\n",
415
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));
416
216
plaintext_length = -1;
418
218
gpgme_decrypt_result_t result;
419
result = gpgme_op_decrypt_result(mc->ctx);
421
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");
423
fprintf_plus(stderr, "Unsupported algorithm: %s\n",
424
result->unsupported_algorithm);
425
fprintf_plus(stderr, "Wrong key usage: %u\n",
426
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);
427
227
if(result->file_name != NULL){
428
fprintf_plus(stderr, "File name: %s\n", result->file_name);
228
fprintf(stderr, "File name: %s\n", result->file_name);
430
230
gpgme_recipient_t recipient;
431
231
recipient = result->recipients;
432
while(recipient != NULL){
433
fprintf_plus(stderr, "Public key algorithm: %s\n",
434
gpgme_pubkey_algo_name
435
(recipient->pubkey_algo));
436
fprintf_plus(stderr, "Key ID: %s\n", recipient->keyid);
437
fprintf_plus(stderr, "Secret key available: %s\n",
438
recipient->status == GPG_ERR_NO_SECKEY
440
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;
818
434
static void empty_log(__attribute__((unused)) AvahiLogLevel level,
819
435
__attribute__((unused)) const char *txt){}
821
/* Set effective uid to 0, return errno */
822
__attribute__((warn_unused_result))
823
int raise_privileges(void){
824
int old_errno = errno;
826
if(seteuid(0) == -1){
833
/* Set effective and real user ID to 0. Return errno. */
834
__attribute__((warn_unused_result))
835
int raise_privileges_permanently(void){
836
int old_errno = errno;
837
int ret = raise_privileges();
849
/* Set effective user ID to unprivileged saved user ID */
850
__attribute__((warn_unused_result))
851
int lower_privileges(void){
852
int old_errno = errno;
854
if(seteuid(uid) == -1){
861
/* Lower privileges permanently */
862
__attribute__((warn_unused_result))
863
int lower_privileges_permanently(void){
864
int old_errno = errno;
866
if(setuid(uid) == -1){
873
/* Helper function to add_local_route() and delete_local_route() */
874
__attribute__((nonnull, warn_unused_result))
875
static bool add_delete_local_route(const bool add,
877
AvahiIfIndex if_index){
879
char helper[] = "mandos-client-iprouteadddel";
880
char add_arg[] = "add";
881
char delete_arg[] = "delete";
882
char debug_flag[] = "--debug";
883
char *pluginhelperdir = getenv("MANDOSPLUGINHELPERDIR");
884
if(pluginhelperdir == NULL){
886
fprintf_plus(stderr, "MANDOSPLUGINHELPERDIR environment"
887
" variable not set; cannot run helper\n");
892
char interface[IF_NAMESIZE];
893
if(if_indextoname((unsigned int)if_index, interface) == NULL){
894
perror_plus("if_indextoname");
898
int devnull = (int)TEMP_FAILURE_RETRY(open("/dev/null", O_RDONLY));
900
perror_plus("open(\"/dev/null\", O_RDONLY)");
906
/* Raise privileges */
907
errno = raise_privileges_permanently();
909
perror_plus("Failed to raise privileges");
910
/* _exit(EX_NOPERM); */
916
perror_plus("setgid");
919
/* Reset supplementary groups */
921
ret = setgroups(0, NULL);
923
perror_plus("setgroups");
927
ret = dup2(devnull, STDIN_FILENO);
929
perror_plus("dup2(devnull, STDIN_FILENO)");
932
ret = close(devnull);
934
perror_plus("close");
937
ret = dup2(STDERR_FILENO, STDOUT_FILENO);
939
perror_plus("dup2(STDERR_FILENO, STDOUT_FILENO)");
942
int helperdir_fd = (int)TEMP_FAILURE_RETRY(open(pluginhelperdir,
947
if(helperdir_fd == -1){
949
_exit(EX_UNAVAILABLE);
951
int helper_fd = (int)TEMP_FAILURE_RETRY(openat(helperdir_fd,
954
perror_plus("openat");
956
_exit(EX_UNAVAILABLE);
960
#pragma GCC diagnostic push
961
#pragma GCC diagnostic ignored "-Wcast-qual"
963
if(fexecve(helper_fd, (char *const [])
964
{ helper, add ? add_arg : delete_arg, (char *)address,
965
interface, debug ? debug_flag : NULL, NULL },
968
#pragma GCC diagnostic pop
970
perror_plus("fexecve");
982
pret = waitpid(pid, &status, 0);
983
if(pret == -1 and errno == EINTR and quit_now){
984
int errno_raising = 0;
985
if((errno = raise_privileges()) != 0){
986
errno_raising = errno;
987
perror_plus("Failed to raise privileges in order to"
988
" kill helper program");
990
if(kill(pid, SIGTERM) == -1){
993
if((errno_raising == 0) and (errno = lower_privileges()) != 0){
994
perror_plus("Failed to lower privileges after killing"
999
} while(pret == -1 and errno == EINTR);
1001
perror_plus("waitpid");
1004
if(WIFEXITED(status)){
1005
if(WEXITSTATUS(status) != 0){
1006
fprintf_plus(stderr, "Error: iprouteadddel exited"
1007
" with status %d\n", WEXITSTATUS(status));
1012
if(WIFSIGNALED(status)){
1013
fprintf_plus(stderr, "Error: iprouteadddel died by"
1014
" signal %d\n", WTERMSIG(status));
1017
fprintf_plus(stderr, "Error: iprouteadddel crashed\n");
1021
__attribute__((nonnull, warn_unused_result))
1022
static bool add_local_route(const char *address,
1023
AvahiIfIndex if_index){
1025
fprintf_plus(stderr, "Adding route to %s\n", address);
1027
return add_delete_local_route(true, address, if_index);
1030
__attribute__((nonnull, warn_unused_result))
1031
static bool delete_local_route(const char *address,
1032
AvahiIfIndex if_index){
1034
fprintf_plus(stderr, "Removing route to %s\n", address);
1036
return add_delete_local_route(false, address, if_index);
1039
437
/* Called when a Mandos server is found */
1040
__attribute__((nonnull, warn_unused_result))
1041
static int start_mandos_communication(const char *ip, in_port_t port,
438
static int start_mandos_communication(const char *ip, uint16_t port,
1042
439
AvahiIfIndex if_index,
1043
int af, mandos_context *mc){
1044
int ret, tcp_sd = -1;
1046
struct sockaddr_storage to;
442
union { struct sockaddr in; struct sockaddr_in6 in6; } to;
1047
443
char *buffer = NULL;
1048
char *decrypted_buffer = NULL;
444
char *decrypted_buffer;
1049
445
size_t buffer_length = 0;
1050
446
size_t buffer_capacity = 0;
447
ssize_t decrypted_buffer_size;
450
char interface[IF_NAMESIZE];
1053
451
gnutls_session_t session;
1054
int pf; /* Protocol family */
1055
bool route_added = false;
1072
fprintf_plus(stderr, "Bad address family: %d\n", af);
1077
/* If the interface is specified and we have a list of interfaces */
1078
if(if_index != AVAHI_IF_UNSPEC and mc->interfaces != NULL){
1079
/* Check if the interface is one of the interfaces we are using */
1082
char *interface = NULL;
1083
while((interface = argz_next(mc->interfaces,
1084
mc->interfaces_size,
1086
if(if_nametoindex(interface) == (unsigned int)if_index){
1093
/* This interface does not match any in the list, so we don't
1094
connect to the server */
1096
char interface[IF_NAMESIZE];
1097
if(if_indextoname((unsigned int)if_index, interface) == NULL){
1098
perror_plus("if_indextoname");
1100
fprintf_plus(stderr, "Skipping server on non-used interface"
1102
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);
1110
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);
1116
fprintf_plus(stderr, "Setting up a TCP connection to %s, port %"
1117
PRIuMAX "\n", ip, (uintmax_t)port);
1120
tcp_sd = socket(pf, SOCK_STREAM | SOCK_CLOEXEC, 0);
1123
perror_plus("socket");
1134
struct sockaddr_in6 *to6 = (struct sockaddr_in6 *)&to;
1135
*to6 = (struct sockaddr_in6){ .sin6_family = (sa_family_t)af };
1136
ret = inet_pton(af, ip, &to6->sin6_addr);
1138
struct sockaddr_in *to4 = (struct sockaddr_in *)&to;
1139
*to4 = (struct sockaddr_in){ .sin_family = (sa_family_t)af };
1140
ret = inet_pton(af, ip, &to4->sin_addr);
1144
perror_plus("inet_pton");
1150
fprintf_plus(stderr, "Bad address: %s\n", ip);
1155
((struct sockaddr_in6 *)&to)->sin6_port = htons(port);
1156
if(IN6_IS_ADDR_LINKLOCAL
1157
(&((struct sockaddr_in6 *)&to)->sin6_addr)){
1158
if(if_index == AVAHI_IF_UNSPEC){
1159
fprintf_plus(stderr, "An IPv6 link-local address is"
1160
" incomplete without a network interface\n");
1164
/* Set the network interface number as scope */
1165
((struct sockaddr_in6 *)&to)->sin6_scope_id = (uint32_t)if_index;
1168
((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;
1177
if(af == AF_INET6 and if_index != AVAHI_IF_UNSPEC){
1178
char interface[IF_NAMESIZE];
1179
if(if_indextoname((unsigned int)if_index, interface) == NULL){
1180
perror_plus("if_indextoname");
1182
fprintf_plus(stderr, "Connection to: %s%%%s, port %" PRIuMAX
1183
"\n", ip, interface, (uintmax_t)port);
1186
fprintf_plus(stderr, "Connection to: %s, port %" PRIuMAX "\n",
1187
ip, (uintmax_t)port);
1189
char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?
1190
INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";
1192
ret = getnameinfo((struct sockaddr *)&to,
1193
sizeof(struct sockaddr_in6),
1194
addrstr, sizeof(addrstr), NULL, 0,
1197
ret = getnameinfo((struct sockaddr *)&to,
1198
sizeof(struct sockaddr_in),
1199
addrstr, sizeof(addrstr), NULL, 0,
1202
if(ret == EAI_SYSTEM){
1203
perror_plus("getnameinfo");
1204
} else if(ret != 0) {
1205
fprintf_plus(stderr, "getnameinfo: %s", gai_strerror(ret));
1206
} else if(strcmp(addrstr, ip) != 0){
1207
fprintf_plus(stderr, "Canonical address form: %s\n", addrstr);
1218
ret = connect(tcp_sd, (struct sockaddr *)&to,
1219
sizeof(struct sockaddr_in6));
1221
ret = connect(tcp_sd, (struct sockaddr *)&to, /* IPv4 */
1222
sizeof(struct sockaddr_in));
1225
if(((errno == ENETUNREACH) or (errno == EHOSTUNREACH))
1226
and if_index != AVAHI_IF_UNSPEC
1227
and connect_to == NULL
1228
and not route_added and
1229
((af == AF_INET6 and not
1230
IN6_IS_ADDR_LINKLOCAL(&(((struct sockaddr_in6 *)
1232
or (af == AF_INET and
1233
/* Not a a IPv4LL address */
1234
(ntohl(((struct sockaddr_in *)&to)->sin_addr.s_addr)
1235
& 0xFFFF0000L) != 0xA9FE0000L))){
1236
/* Work around Avahi bug - Avahi does not announce link-local
1237
addresses if it has a global address, so local hosts with
1238
*only* a link-local address (e.g. Mandos clients) cannot
1239
connect to a Mandos server announced by Avahi on a server
1240
host with a global address. Work around this by retrying
1241
with an explicit route added with the server's address.
1243
Avahi bug reference:
1244
https://lists.freedesktop.org/archives/avahi/2010-February/001833.html
1245
https://bugs.debian.org/587961
1248
fprintf_plus(stderr, "Mandos server unreachable, trying"
1252
route_added = add_local_route(ip, if_index);
1258
if(errno != ECONNREFUSED or debug){
1260
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));
1273
514
const char *out = mandos_protocol_version;
1276
517
size_t out_size = strlen(out);
1277
ret = (int)TEMP_FAILURE_RETRY(write(tcp_sd, out + written,
1278
out_size - written));
1281
perror_plus("write");
518
ret = TEMP_FAILURE_RETRY(write(tcp_sd, out + written,
519
out_size - written));
1283
523
goto mandos_end;
1285
525
written += (size_t)ret;
1286
526
if(written < out_size){
1289
if(out == mandos_protocol_version){
529
if (out == mandos_protocol_version){
1304
fprintf_plus(stderr, "Establishing TLS session with %s\n", ip);
1312
/* This casting via intptr_t is to eliminate warning about casting
1313
an int to a pointer type. This is exactly how the GnuTLS Guile
1314
function "set-session-transport-fd!" does it. */
1315
gnutls_transport_set_ptr(session,
1316
(gnutls_transport_ptr_t)(intptr_t)tcp_sd);
1324
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);
1329
546
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
1331
if(ret != GNUTLS_E_SUCCESS){
548
if (ret != GNUTLS_E_SUCCESS){
1333
fprintf_plus(stderr, "*** GnuTLS Handshake failed ***\n");
550
fprintf(stderr, "*** GnuTLS Handshake failed ***\n");
1337
554
goto mandos_end;
1340
557
/* Read OpenPGP packet that contains the wanted password */
1343
fprintf_plus(stderr, "Retrieving OpenPGP encrypted password from"
560
fprintf(stderr, "Retrieving pgp encrypted password from %s\n",
1354
buffer_capacity = incbuffer(&buffer, buffer_length,
1356
if(buffer_capacity == 0){
1358
perror_plus("incbuffer");
1368
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,
1375
580
case GNUTLS_E_INTERRUPTED:
1376
581
case GNUTLS_E_AGAIN:
1378
583
case GNUTLS_E_REHANDSHAKE:
1380
ret = gnutls_handshake(session);
585
ret = gnutls_handshake (session);
1386
586
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
1388
fprintf_plus(stderr, "*** GnuTLS Re-handshake failed "
588
fprintf(stderr, "*** GnuTLS Re-handshake failed ***\n");
1392
591
goto mandos_end;
1396
fprintf_plus(stderr, "Unknown error while reading data from"
1397
" encrypted session with Mandos server\n");
1398
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);
1400
599
goto mandos_end;
1403
buffer_length += (size_t) sret;
602
buffer_length += (size_t) ret;
1408
fprintf_plus(stderr, "Closing TLS session\n");
1417
ret = gnutls_bye(session, GNUTLS_SHUT_RDWR);
1422
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
1424
if(buffer_length > 0){
1425
ssize_t decrypted_buffer_size;
1426
decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,
1427
&decrypted_buffer, mc);
1428
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){
1432
619
while(written < (size_t) decrypted_buffer_size){
1438
ret = (int)fwrite(decrypted_buffer + written, 1,
1439
(size_t)decrypted_buffer_size - written,
620
ret = (int)fwrite (decrypted_buffer + written, 1,
621
(size_t)decrypted_buffer_size - written,
1441
623
if(ret == 0 and ferror(stdout)){
1444
fprintf_plus(stderr, "Error writing encrypted data: %s\n",
625
fprintf(stderr, "Error writing encrypted data: %s\n",
1450
631
written += (size_t)ret;
1452
ret = fflush(stdout);
1456
fprintf_plus(stderr, "Error writing encrypted data: %s\n",
633
free(decrypted_buffer);
1466
641
/* Shutdown procedure */
1471
if(not delete_local_route(ip, if_index)){
1472
fprintf_plus(stderr, "Failed to delete local route to %s on"
1473
" interface %d", ip, if_index);
1477
free(decrypted_buffer);
1480
ret = close(tcp_sd);
1486
perror_plus("close");
1488
gnutls_deinit(session);
646
gnutls_deinit (session);
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 devnull = (int)TEMP_FAILURE_RETRY(open("/dev/null", O_RDONLY));
1928
perror_plus("open(\"/dev/null\", O_RDONLY)");
1931
int numhooks = scandirat(hookdir_fd, ".", &direntries,
1932
runnable_hook, alphasort);
1934
perror_plus("scandir");
1938
struct dirent *direntry;
1940
for(int i = 0; i < numhooks; i++){
1941
direntry = direntries[i];
1943
fprintf_plus(stderr, "Running network hook \"%s\"\n",
1946
pid_t hook_pid = fork();
1949
/* Raise privileges */
1950
errno = raise_privileges_permanently();
1952
perror_plus("Failed to raise privileges");
1959
perror_plus("setgid");
1962
/* Reset supplementary groups */
1964
ret = setgroups(0, NULL);
1966
perror_plus("setgroups");
1969
ret = setenv("MANDOSNETHOOKDIR", hookdir, 1);
1971
perror_plus("setenv");
1974
ret = setenv("DEVICE", interface, 1);
1976
perror_plus("setenv");
1979
ret = setenv("VERBOSITY", debug ? "1" : "0", 1);
1981
perror_plus("setenv");
1984
ret = setenv("MODE", mode, 1);
1986
perror_plus("setenv");
1990
ret = asprintf(&delaystring, "%f", (double)delay);
1992
perror_plus("asprintf");
1995
ret = setenv("DELAY", delaystring, 1);
1998
perror_plus("setenv");
2002
if(connect_to != NULL){
2003
ret = setenv("CONNECT", connect_to, 1);
2005
perror_plus("setenv");
2009
int hook_fd = (int)TEMP_FAILURE_RETRY(openat(hookdir_fd,
2013
perror_plus("openat");
2014
_exit(EXIT_FAILURE);
2016
if(close(hookdir_fd) == -1){
2017
perror_plus("close");
2018
_exit(EXIT_FAILURE);
2020
ret = dup2(devnull, STDIN_FILENO);
2022
perror_plus("dup2(devnull, STDIN_FILENO)");
2025
ret = close(devnull);
2027
perror_plus("close");
2030
ret = dup2(STDERR_FILENO, STDOUT_FILENO);
2032
perror_plus("dup2(STDERR_FILENO, STDOUT_FILENO)");
2035
if(fexecve(hook_fd, (char *const []){ direntry->d_name, NULL },
2037
perror_plus("fexecve");
2038
_exit(EXIT_FAILURE);
2042
perror_plus("fork");
2047
if(TEMP_FAILURE_RETRY(waitpid(hook_pid, &status, 0)) == -1){
2048
perror_plus("waitpid");
2052
if(WIFEXITED(status)){
2053
if(WEXITSTATUS(status) != 0){
2054
fprintf_plus(stderr, "Warning: network hook \"%s\" exited"
2055
" with status %d\n", direntry->d_name,
2056
WEXITSTATUS(status));
2060
} else if(WIFSIGNALED(status)){
2061
fprintf_plus(stderr, "Warning: network hook \"%s\" died by"
2062
" signal %d\n", direntry->d_name,
2067
fprintf_plus(stderr, "Warning: network hook \"%s\""
2068
" crashed\n", direntry->d_name);
2074
fprintf_plus(stderr, "Network hook \"%s\" ran successfully\n",
2080
if(close(hookdir_fd) == -1){
2081
perror_plus("close");
2088
__attribute__((nonnull, warn_unused_result))
2089
int bring_up_interface(const char *const interface,
2091
int old_errno = errno;
2093
struct ifreq network;
2094
unsigned int if_index = if_nametoindex(interface);
2096
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
2106
if(not interface_is_up(interface)){
2108
int ioctl_errno = 0;
2109
if(not get_flags(interface, &network)){
2111
fprintf_plus(stderr, "Failed to get flags for interface "
2112
"\"%s\"\n", interface);
2116
network.ifr_flags |= IFF_UP; /* set flag */
2118
int sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
2121
perror_plus("socket");
2129
perror_plus("close");
2136
fprintf_plus(stderr, "Bringing up interface \"%s\"\n",
2140
/* Raise privileges */
2141
ret_errno = raise_privileges();
2144
perror_plus("Failed to raise privileges");
2149
bool restore_loglevel = false;
2151
/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO
2152
messages about the network interface to mess up the prompt */
2153
ret_linux = klogctl(8, NULL, 5);
2154
if(ret_linux == -1){
2155
perror_plus("klogctl");
2157
restore_loglevel = true;
2160
#endif /* __linux__ */
2161
int ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
2162
ioctl_errno = errno;
2164
if(restore_loglevel){
2165
ret_linux = klogctl(7, NULL, 0);
2166
if(ret_linux == -1){
2167
perror_plus("klogctl");
2170
#endif /* __linux__ */
2172
/* If raise_privileges() succeeded above */
2174
/* Lower privileges */
2175
ret_errno = lower_privileges();
2178
perror_plus("Failed to lower privileges");
2182
/* Close the socket */
2185
perror_plus("close");
2188
if(ret_setflags == -1){
2189
errno = ioctl_errno;
2190
perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");
2195
fprintf_plus(stderr, "Interface \"%s\" is already up; good\n",
2199
/* Sleep checking until interface is running.
2200
Check every 0.25s, up to total time of delay */
2201
for(int i = 0; i < delay * 4; i++){
2202
if(interface_is_running(interface)){
2205
struct timespec sleeptime = { .tv_nsec = 250000000 };
2206
ret = nanosleep(&sleeptime, NULL);
2207
if(ret == -1 and errno != EINTR){
2208
perror_plus("nanosleep");
2216
__attribute__((nonnull, warn_unused_result))
2217
int take_down_interface(const char *const interface){
2218
int old_errno = errno;
2219
struct ifreq network;
2220
unsigned int if_index = if_nametoindex(interface);
2222
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
2226
if(interface_is_up(interface)){
2228
int ioctl_errno = 0;
2229
if(not get_flags(interface, &network) and debug){
2231
fprintf_plus(stderr, "Failed to get flags for interface "
2232
"\"%s\"\n", interface);
2236
network.ifr_flags &= ~(short)IFF_UP; /* clear flag */
2238
int sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
2241
perror_plus("socket");
2247
fprintf_plus(stderr, "Taking down interface \"%s\"\n",
2251
/* Raise privileges */
2252
ret_errno = raise_privileges();
2255
perror_plus("Failed to raise privileges");
2258
int ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
2259
ioctl_errno = errno;
2261
/* If raise_privileges() succeeded above */
2263
/* Lower privileges */
2264
ret_errno = lower_privileges();
2267
perror_plus("Failed to lower privileges");
2271
/* Close the socket */
2272
int ret = close(sd);
2274
perror_plus("close");
2277
if(ret_setflags == -1){
2278
errno = ioctl_errno;
2279
perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");
2284
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);
2292
759
int main(int argc, char *argv[]){
2293
mandos_context mc = { .server = NULL, .dh_bits = 0,
2294
.priority = "SECURE256:!CTYPE-X.509"
2295
":+CTYPE-OPENPGP:!RSA:+SIGN-DSA-SHA256",
2296
.current_server = NULL, .interfaces = NULL,
2297
.interfaces_size = 0 };
2298
AvahiSServiceBrowser *sb = NULL;
2303
int exitcode = EXIT_SUCCESS;
2304
char *interfaces_to_take_down = NULL;
2305
size_t interfaces_to_take_down_size = 0;
2306
char run_tempdir[] = "/run/tmp/mandosXXXXXX";
2307
char old_tempdir[] = "/tmp/mandosXXXXXX";
2308
char *tempdir = NULL;
2309
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
2310
const char *seckey = PATHDIR "/" SECKEY;
2311
const char *pubkey = PATHDIR "/" PUBKEY;
2312
const char *dh_params_file = NULL;
2313
char *interfaces_hooks = NULL;
2315
bool gnutls_initialized = false;
2316
bool gpgme_initialized = false;
2318
double retry_interval = 10; /* 10s between trying a server and
2319
retrying the same server again */
2321
struct sigaction old_sigterm_action = { .sa_handler = SIG_DFL };
2322
struct sigaction sigterm_action = { .sa_handler = handle_sigterm };
2327
/* Lower any group privileges we might have, just to be safe */
2331
perror_plus("setgid");
2334
/* Lower user privileges (temporarily) */
2338
perror_plus("seteuid");
2346
struct argp_option options[] = {
2347
{ .name = "debug", .key = 128,
2348
.doc = "Debug mode", .group = 3 },
2349
{ .name = "connect", .key = 'c',
2350
.arg = "ADDRESS:PORT",
2351
.doc = "Connect directly to a specific Mandos server",
2353
{ .name = "interface", .key = 'i',
2355
.doc = "Network interface that will be used to search for"
2358
{ .name = "seckey", .key = 's',
2360
.doc = "OpenPGP secret key file base name",
2362
{ .name = "pubkey", .key = 'p',
2364
.doc = "OpenPGP public key file base name",
2366
{ .name = "dh-bits", .key = 129,
2368
.doc = "Bit length of the prime number used in the"
2369
" Diffie-Hellman key exchange",
2371
{ .name = "dh-params", .key = 134,
2373
.doc = "PEM-encoded PKCS#3 file with pre-generated parameters"
2374
" for the Diffie-Hellman key exchange",
2376
{ .name = "priority", .key = 130,
2378
.doc = "GnuTLS priority string for the TLS handshake",
2380
{ .name = "delay", .key = 131,
2382
.doc = "Maximum delay to wait for interface startup",
2384
{ .name = "retry", .key = 132,
2386
.doc = "Retry interval used when denied by the Mandos server",
2388
{ .name = "network-hook-dir", .key = 133,
2390
.doc = "Directory where network hooks are located",
2393
* These reproduce what we would get without ARGP_NO_HELP
2395
{ .name = "help", .key = '?',
2396
.doc = "Give this help list", .group = -1 },
2397
{ .name = "usage", .key = -3,
2398
.doc = "Give a short usage message", .group = -1 },
2399
{ .name = "version", .key = 'V',
2400
.doc = "Print program version", .group = -1 },
2404
error_t parse_opt(int key, char *arg,
2405
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;
2408
case 128: /* --debug */
2411
case 'c': /* --connect */
2414
case 'i': /* --interface */
2415
ret_errno = argz_add_sep(&mc.interfaces, &mc.interfaces_size,
2418
argp_error(state, "%s", strerror(ret_errno));
2421
case 's': /* --seckey */
2424
case 'p': /* --pubkey */
2427
case 129: /* --dh-bits */
2429
tmpmax = strtoimax(arg, &tmp, 10);
2430
if(errno != 0 or tmp == arg or *tmp != '\0'
2431
or tmpmax != (typeof(mc.dh_bits))tmpmax){
2432
argp_error(state, "Bad number of DH bits");
2434
mc.dh_bits = (typeof(mc.dh_bits))tmpmax;
2436
case 134: /* --dh-params */
2437
dh_params_file = arg;
2439
case 130: /* --priority */
2442
case 131: /* --delay */
2444
delay = strtof(arg, &tmp);
2445
if(errno != 0 or tmp == arg or *tmp != '\0'){
2446
argp_error(state, "Bad delay");
2448
case 132: /* --retry */
2450
retry_interval = strtod(arg, &tmp);
2451
if(errno != 0 or tmp == arg or *tmp != '\0'
2452
or (retry_interval * 1000) > INT_MAX
2453
or retry_interval < 0){
2454
argp_error(state, "Bad retry interval");
2457
case 133: /* --network-hook-dir */
2461
* These reproduce what we would get without ARGP_NO_HELP
2463
case '?': /* --help */
2464
argp_state_help(state, state->out_stream,
2465
(ARGP_HELP_STD_HELP | ARGP_HELP_EXIT_ERR)
2466
& ~(unsigned int)ARGP_HELP_EXIT_OK);
2467
case -3: /* --usage */
2468
argp_state_help(state, state->out_stream,
2469
ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);
2470
case 'V': /* --version */
2471
fprintf_plus(state->out_stream, "%s\n", argp_program_version);
2472
exit(argp_err_exit_status);
2475
return ARGP_ERR_UNKNOWN;
2480
struct argp argp = { .options = options, .parser = parse_opt,
2482
.doc = "Mandos client -- Get and decrypt"
2483
" passwords from a Mandos server" };
2484
ret_errno = argp_parse(&argp, argc, argv,
2485
ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);
2492
perror_plus("argp_parse");
2493
exitcode = EX_OSERR;
2496
exitcode = EX_USAGE;
2502
/* Work around Debian bug #633582:
2503
<https://bugs.debian.org/633582> */
2505
/* Re-raise privileges */
2506
ret = raise_privileges();
2509
perror_plus("Failed to raise privileges");
2513
if(strcmp(seckey, PATHDIR "/" SECKEY) == 0){
2514
int seckey_fd = open(seckey, O_RDONLY);
2515
if(seckey_fd == -1){
2516
perror_plus("open");
2518
ret = (int)TEMP_FAILURE_RETRY(fstat(seckey_fd, &st));
2520
perror_plus("fstat");
2522
if(S_ISREG(st.st_mode)
2523
and st.st_uid == 0 and st.st_gid == 0){
2524
ret = fchown(seckey_fd, uid, gid);
2526
perror_plus("fchown");
2534
if(strcmp(pubkey, PATHDIR "/" PUBKEY) == 0){
2535
int pubkey_fd = open(pubkey, O_RDONLY);
2536
if(pubkey_fd == -1){
2537
perror_plus("open");
2539
ret = (int)TEMP_FAILURE_RETRY(fstat(pubkey_fd, &st));
2541
perror_plus("fstat");
2543
if(S_ISREG(st.st_mode)
2544
and st.st_uid == 0 and st.st_gid == 0){
2545
ret = fchown(pubkey_fd, uid, gid);
2547
perror_plus("fchown");
2555
if(dh_params_file != NULL
2556
and strcmp(dh_params_file, PATHDIR "/dhparams.pem" ) == 0){
2557
int dhparams_fd = open(dh_params_file, O_RDONLY);
2558
if(dhparams_fd == -1){
2559
perror_plus("open");
2561
ret = (int)TEMP_FAILURE_RETRY(fstat(dhparams_fd, &st));
2563
perror_plus("fstat");
2565
if(S_ISREG(st.st_mode)
2566
and st.st_uid == 0 and st.st_gid == 0){
2567
ret = fchown(dhparams_fd, uid, gid);
2569
perror_plus("fchown");
2577
/* Lower privileges */
2578
ret = lower_privileges();
2581
perror_plus("Failed to lower privileges");
2586
/* Remove invalid interface names (except "none") */
2588
char *interface = NULL;
2589
while((interface = argz_next(mc.interfaces, mc.interfaces_size,
2591
if(strcmp(interface, "none") != 0
2592
and if_nametoindex(interface) == 0){
2593
if(interface[0] != '\0'){
2594
fprintf_plus(stderr, "Not using nonexisting interface"
2595
" \"%s\"\n", interface);
2597
argz_delete(&mc.interfaces, &mc.interfaces_size, interface);
2603
/* Run network hooks */
2605
if(mc.interfaces != NULL){
2606
interfaces_hooks = malloc(mc.interfaces_size);
2607
if(interfaces_hooks == NULL){
2608
perror_plus("malloc");
952
uint16_t port = (uint16_t) strtol(address+1, NULL, 10);
954
perror("Bad port number");
955
exitcode = EXIT_FAILURE;
2611
memcpy(interfaces_hooks, mc.interfaces, mc.interfaces_size);
2612
argz_stringify(interfaces_hooks, mc.interfaces_size, (int)',');
2614
run_network_hooks("start", interfaces_hooks != NULL ?
2615
interfaces_hooks : "", delay);
2619
avahi_set_log_function(empty_log);
2622
/* Initialize Avahi early so avahi_simple_poll_quit() can be called
2623
from the signal handler */
2624
/* Initialize the pseudo-RNG for Avahi */
2625
srand((unsigned int) time(NULL));
2626
simple_poll = avahi_simple_poll_new();
2627
if(simple_poll == NULL){
2628
fprintf_plus(stderr,
2629
"Avahi: Failed to create simple poll object.\n");
2630
exitcode = EX_UNAVAILABLE;
2634
sigemptyset(&sigterm_action.sa_mask);
2635
ret = sigaddset(&sigterm_action.sa_mask, SIGINT);
2637
perror_plus("sigaddset");
2638
exitcode = EX_OSERR;
2641
ret = sigaddset(&sigterm_action.sa_mask, SIGHUP);
2643
perror_plus("sigaddset");
2644
exitcode = EX_OSERR;
2647
ret = sigaddset(&sigterm_action.sa_mask, SIGTERM);
2649
perror_plus("sigaddset");
2650
exitcode = EX_OSERR;
2653
/* Need to check if the handler is SIG_IGN before handling:
2654
| [[info:libc:Initial Signal Actions]] |
2655
| [[info:libc:Basic Signal Handling]] |
2657
ret = sigaction(SIGINT, NULL, &old_sigterm_action);
2659
perror_plus("sigaction");
2662
if(old_sigterm_action.sa_handler != SIG_IGN){
2663
ret = sigaction(SIGINT, &sigterm_action, NULL);
2665
perror_plus("sigaction");
2666
exitcode = EX_OSERR;
2670
ret = sigaction(SIGHUP, NULL, &old_sigterm_action);
2672
perror_plus("sigaction");
2675
if(old_sigterm_action.sa_handler != SIG_IGN){
2676
ret = sigaction(SIGHUP, &sigterm_action, NULL);
2678
perror_plus("sigaction");
2679
exitcode = EX_OSERR;
2683
ret = sigaction(SIGTERM, NULL, &old_sigterm_action);
2685
perror_plus("sigaction");
2688
if(old_sigterm_action.sa_handler != SIG_IGN){
2689
ret = sigaction(SIGTERM, &sigterm_action, NULL);
2691
perror_plus("sigaction");
2692
exitcode = EX_OSERR;
2697
/* If no interfaces were specified, make a list */
2698
if(mc.interfaces == NULL){
2699
struct dirent **direntries = NULL;
2700
/* Look for any good interfaces */
2701
ret = scandir(sys_class_net, &direntries, good_interface,
2704
/* Add all found interfaces to interfaces list */
2705
for(int i = 0; i < ret; ++i){
2706
ret_errno = argz_add(&mc.interfaces, &mc.interfaces_size,
2707
direntries[i]->d_name);
2710
perror_plus("argz_add");
2711
free(direntries[i]);
2715
fprintf_plus(stderr, "Will use interface \"%s\"\n",
2716
direntries[i]->d_name);
2718
free(direntries[i]);
2725
fprintf_plus(stderr, "Could not find a network interface\n");
2726
exitcode = EXIT_FAILURE;
2731
/* Bring up interfaces which are down, and remove any "none"s */
2733
char *interface = NULL;
2734
while((interface = argz_next(mc.interfaces, mc.interfaces_size,
2736
/* If interface name is "none", stop bringing up interfaces.
2737
Also remove all instances of "none" from the list */
2738
if(strcmp(interface, "none") == 0){
2739
argz_delete(&mc.interfaces, &mc.interfaces_size,
2742
while((interface = argz_next(mc.interfaces,
2743
mc.interfaces_size, interface))){
2744
if(strcmp(interface, "none") == 0){
2745
argz_delete(&mc.interfaces, &mc.interfaces_size,
2752
bool interface_was_up = interface_is_up(interface);
2753
errno = bring_up_interface(interface, delay);
2754
if(not interface_was_up){
2756
fprintf_plus(stderr, "Failed to bring up interface \"%s\":"
2757
" %s\n", interface, strerror(errno));
2759
errno = argz_add(&interfaces_to_take_down,
2760
&interfaces_to_take_down_size,
2763
perror_plus("argz_add");
2768
if(debug and (interfaces_to_take_down == NULL)){
2769
fprintf_plus(stderr, "No interfaces were brought up\n");
2773
/* If we only got one interface, explicitly use only that one */
2774
if(argz_count(mc.interfaces, mc.interfaces_size) == 1){
2776
fprintf_plus(stderr, "Using only interface \"%s\"\n",
2779
if_index = (AvahiIfIndex)if_nametoindex(mc.interfaces);
2786
ret = init_gnutls_global(pubkey, seckey, dh_params_file, &mc);
2788
fprintf_plus(stderr, "init_gnutls_global failed\n");
2789
exitcode = EX_UNAVAILABLE;
2792
gnutls_initialized = true;
2799
/* Try /run/tmp before /tmp */
2800
tempdir = mkdtemp(run_tempdir);
2801
if(tempdir == NULL and errno == ENOENT){
2803
fprintf_plus(stderr, "Tempdir %s did not work, trying %s\n",
2804
run_tempdir, old_tempdir);
2806
tempdir = mkdtemp(old_tempdir);
2808
if(tempdir == NULL){
2809
perror_plus("mkdtemp");
2817
if(not init_gpgme(pubkey, seckey, tempdir, &mc)){
2818
fprintf_plus(stderr, "init_gpgme failed\n");
2819
exitcode = EX_UNAVAILABLE;
2822
gpgme_initialized = true;
2829
if(connect_to != NULL){
2830
/* Connect directly, do not use Zeroconf */
2831
/* (Mainly meant for debugging) */
2832
char *address = strrchr(connect_to, ':');
2834
if(address == NULL){
2835
fprintf_plus(stderr, "No colon in address\n");
2836
exitcode = EX_USAGE;
2846
tmpmax = strtoimax(address+1, &tmp, 10);
2847
if(errno != 0 or tmp == address+1 or *tmp != '\0'
2848
or tmpmax != (in_port_t)tmpmax){
2849
fprintf_plus(stderr, "Bad port number\n");
2850
exitcode = EX_USAGE;
2858
port = (in_port_t)tmpmax;
2860
/* Colon in address indicates IPv6 */
2862
if(strchr(connect_to, ':') != NULL){
2864
/* Accept [] around IPv6 address - see RFC 5952 */
2865
if(connect_to[0] == '[' and address[-1] == ']')
2873
address = connect_to;
2879
while(not quit_now){
2880
ret = start_mandos_communication(address, port, if_index, af,
2882
if(quit_now or ret == 0){
2886
fprintf_plus(stderr, "Retrying in %d seconds\n",
2887
(int)retry_interval);
2889
sleep((unsigned int)retry_interval);
2893
exitcode = EXIT_SUCCESS;
2904
AvahiServerConfig config;
2905
/* Do not publish any local Zeroconf records */
2906
avahi_server_config_init(&config);
2907
config.publish_hinfo = 0;
2908
config.publish_addresses = 0;
2909
config.publish_workstation = 0;
2910
config.publish_domain = 0;
2912
/* Allocate a new server */
2913
mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),
2914
&config, NULL, NULL, &ret);
2916
/* Free the Avahi configuration data */
2917
avahi_server_config_free(&config);
2920
/* Check if creating the Avahi server object succeeded */
2921
if(mc.server == NULL){
2922
fprintf_plus(stderr, "Failed to create Avahi server: %s\n",
2923
avahi_strerror(ret));
2924
exitcode = EX_UNAVAILABLE;
2932
/* Create the Avahi service browser */
2933
sb = avahi_s_service_browser_new(mc.server, if_index,
2934
AVAHI_PROTO_UNSPEC, "_mandos._tcp",
2935
NULL, 0, browse_callback,
2938
fprintf_plus(stderr, "Failed to create service browser: %s\n",
2939
avahi_strerror(avahi_server_errno(mc.server)));
2940
exitcode = EX_UNAVAILABLE;
2948
/* Run the main loop */
2951
fprintf_plus(stderr, "Starting Avahi loop search\n");
2954
ret = avahi_loop_with_timeout(simple_poll,
2955
(int)(retry_interval * 1000), &mc);
2957
fprintf_plus(stderr, "avahi_loop_with_timeout exited %s\n",
2958
(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);
2964
if(signal_received){
2965
fprintf_plus(stderr, "%s exiting due to signal %d: %s\n",
2966
argv[0], signal_received,
2967
strsignal(signal_received));
2969
fprintf_plus(stderr, "%s exiting\n", argv[0]);
2973
/* Cleanup things */
2974
free(mc.interfaces);
2977
avahi_s_service_browser_free(sb);
2979
if(mc.server != NULL)
2980
avahi_server_free(mc.server);
2982
if(simple_poll != NULL)
2983
avahi_simple_poll_free(simple_poll);
2985
if(gnutls_initialized){
2986
gnutls_certificate_free_credentials(mc.cred);
2987
gnutls_dh_params_deinit(mc.dh_params);
2990
if(gpgme_initialized){
2991
gpgme_release(mc.ctx);
2994
/* Cleans up the circular linked list of Mandos servers the client
2996
if(mc.current_server != NULL){
2997
mc.current_server->prev->next = NULL;
2998
while(mc.current_server != NULL){
2999
server *next = mc.current_server->next;
3001
#pragma GCC diagnostic push
3002
#pragma GCC diagnostic ignored "-Wcast-qual"
3004
free((char *)(mc.current_server->ip));
3006
#pragma GCC diagnostic pop
3008
free(mc.current_server);
3009
mc.current_server = next;
3013
/* Re-raise privileges */
3015
ret = raise_privileges();
3018
perror_plus("Failed to raise privileges");
3021
/* Run network hooks */
3022
run_network_hooks("stop", interfaces_hooks != NULL ?
3023
interfaces_hooks : "", delay);
3025
/* Take down the network interfaces which were brought up */
3027
char *interface = NULL;
3028
while((interface = argz_next(interfaces_to_take_down,
3029
interfaces_to_take_down_size,
3031
ret = take_down_interface(interface);
3034
perror_plus("Failed to take down interface");
3037
if(debug and (interfaces_to_take_down == NULL)){
3038
fprintf_plus(stderr, "No interfaces needed to be taken"
3044
ret = lower_privileges_permanently();
3047
perror_plus("Failed to lower privileges permanently");
3051
free(interfaces_to_take_down);
3052
free(interfaces_hooks);
3054
void clean_dir_at(int base, const char * const dirname,
3056
struct dirent **direntries = NULL;
3058
int dir_fd = (int)TEMP_FAILURE_RETRY(openat(base, dirname,
3064
perror_plus("open");
3067
int numentries = scandirat(dir_fd, ".", &direntries,
3068
notdotentries, alphasort);
3069
if(numentries >= 0){
3070
for(int i = 0; i < numentries; i++){
3072
fprintf_plus(stderr, "Unlinking \"%s/%s\"\n",
3073
dirname, direntries[i]->d_name);
3075
dret = unlinkat(dir_fd, direntries[i]->d_name, 0);
3077
if(errno == EISDIR){
3078
dret = unlinkat(dir_fd, direntries[i]->d_name,
3081
if((dret == -1) and (errno == ENOTEMPTY)
3082
and (strcmp(direntries[i]->d_name, "private-keys-v1.d")
3083
== 0) and (level == 0)){
3084
/* Recurse only in this special case */
3085
clean_dir_at(dir_fd, direntries[i]->d_name, level+1);
3088
if((dret == -1) and (errno != ENOENT)){
3089
fprintf_plus(stderr, "unlink(\"%s/%s\"): %s\n", dirname,
3090
direntries[i]->d_name, strerror(errno));
3093
free(direntries[i]);
3096
/* need to clean even if 0 because man page doesn't specify */
3098
dret = unlinkat(base, dirname, AT_REMOVEDIR);
3099
if(dret == -1 and errno != ENOENT){
3100
perror_plus("rmdir");
3103
perror_plus("scandirat");
3108
/* Removes the GPGME temp directory and all files inside */
3109
if(tempdir != NULL){
3110
clean_dir_at(-1, tempdir, 0);
3114
sigemptyset(&old_sigterm_action.sa_mask);
3115
old_sigterm_action.sa_handler = SIG_DFL;
3116
ret = (int)TEMP_FAILURE_RETRY(sigaction(signal_received,
3117
&old_sigterm_action,
3120
perror_plus("sigaction");
3123
ret = raise(signal_received);
3124
} while(ret != 0 and errno == EINTR);
3126
perror_plus("raise");
3129
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 ();