131
99
#define BUFFER_SIZE 256
133
#define PATHDIR "/conf/conf.d/mandos"
134
#define SECKEY "seckey.txt"
135
#define PUBKEY "pubkey.txt"
136
#define HOOKDIR "/lib/mandos/network-hooks.d"
138
101
bool debug = false;
102
static const char *keydir = "/conf/conf.d/mandos";
139
103
static const char mandos_protocol_version[] = "1";
140
const char *argp_program_version = "mandos-client " VERSION;
141
const char *argp_program_bug_address = "<mandos@recompile.se>";
142
static const char sys_class_net[] = "/sys/class/net";
143
char *connect_to = NULL;
144
const char *hookdir = HOOKDIR;
149
/* Doubly linked list that need to be circularly linked when used */
150
typedef struct server{
153
AvahiIfIndex if_index;
155
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>";
160
107
/* Used for passing in values through the Avahi callback functions */
109
AvahiSimplePoll *simple_poll;
162
110
AvahiServer *server;
163
111
gnutls_certificate_credentials_t cred;
164
112
unsigned int dh_bits;
165
113
gnutls_dh_params_t dh_params;
166
114
const char *priority;
168
server *current_server;
170
size_t interfaces_size;
171
115
} mandos_context;
173
/* global so signal handler can reach it*/
174
AvahiSimplePoll *simple_poll;
176
sig_atomic_t quit_now = 0;
177
int signal_received = 0;
179
/* Function to use when printing errors */
180
void perror_plus(const char *print_text){
182
fprintf(stderr, "Mandos plugin %s: ",
183
program_invocation_short_name);
188
__attribute__((format (gnu_printf, 2, 3), nonnull))
189
int fprintf_plus(FILE *stream, const char *format, ...){
191
va_start (ap, format);
193
TEMP_FAILURE_RETRY(fprintf(stream, "Mandos plugin %s: ",
194
program_invocation_short_name));
195
return (int)TEMP_FAILURE_RETRY(vfprintf(stream, format, ap));
199
* Make additional room in "buffer" for at least BUFFER_SIZE more
200
* 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,
201
120
* "buffer_length" is how much is already used.
203
__attribute__((nonnull, warn_unused_result))
204
size_t incbuffer(char **buffer, size_t buffer_length,
205
size_t buffer_capacity){
206
if(buffer_length + BUFFER_SIZE > buffer_capacity){
207
char *new_buf = realloc(*buffer, buffer_capacity + BUFFER_SIZE);
209
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);
216
129
buffer_capacity += BUFFER_SIZE;
218
131
return buffer_capacity;
221
/* Add server to set of servers to retry periodically */
222
__attribute__((nonnull, warn_unused_result))
223
bool add_server(const char *ip, in_port_t port, AvahiIfIndex if_index,
224
int af, server **current_server){
226
server *new_server = malloc(sizeof(server));
227
if(new_server == NULL){
228
perror_plus("malloc");
231
*new_server = (server){ .ip = strdup(ip),
233
.if_index = if_index,
235
if(new_server->ip == NULL){
236
perror_plus("strdup");
240
ret = clock_gettime(CLOCK_MONOTONIC, &(new_server->last_seen));
242
perror_plus("clock_gettime");
244
#pragma GCC diagnostic push
245
#pragma GCC diagnostic ignored "-Wcast-qual"
247
free((char *)(new_server->ip));
249
#pragma GCC diagnostic pop
254
/* Special case of first server */
255
if(*current_server == NULL){
256
new_server->next = new_server;
257
new_server->prev = new_server;
258
*current_server = new_server;
260
/* Place the new server last in the list */
261
new_server->next = *current_server;
262
new_server->prev = (*current_server)->prev;
263
new_server->prev->next = new_server;
264
(*current_server)->prev = new_server;
135
* Decrypt OpenPGP data using keyrings in HOMEDIR.
136
* Returns -1 on error
272
__attribute__((nonnull, warn_unused_result))
273
static bool init_gpgme(const char * const seckey,
274
const char * const pubkey,
275
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;
277
144
gpgme_error_t rc;
146
size_t plaintext_capacity = 0;
147
ssize_t plaintext_length = 0;
278
148
gpgme_engine_info_t engine_info;
281
* Helper function to insert pub and seckey to the engine keyring.
283
bool import_key(const char * const filename){
286
gpgme_data_t pgp_data;
288
fd = (int)TEMP_FAILURE_RETRY(open(filename, O_RDONLY));
294
rc = gpgme_data_new_from_fd(&pgp_data, fd);
295
if(rc != GPG_ERR_NO_ERROR){
296
fprintf_plus(stderr, "bad gpgme_data_new_from_fd: %s: %s\n",
297
gpgme_strsource(rc), gpgme_strerror(rc));
301
rc = gpgme_op_import(mc->ctx, pgp_data);
302
if(rc != GPG_ERR_NO_ERROR){
303
fprintf_plus(stderr, "bad gpgme_op_import: %s: %s\n",
304
gpgme_strsource(rc), gpgme_strerror(rc));
310
perror_plus("close");
312
gpgme_data_release(pgp_data);
317
fprintf_plus(stderr, "Initializing GPGME\n");
151
fprintf(stderr, "Trying to decrypt OpenPGP data\n");
321
155
gpgme_check_version(NULL);
322
156
rc = gpgme_engine_check_version(GPGME_PROTOCOL_OpenPGP);
323
if(rc != GPG_ERR_NO_ERROR){
324
fprintf_plus(stderr, "bad gpgme_engine_check_version: %s: %s\n",
325
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));
329
163
/* Set GPGME home directory for the OpenPGP engine only */
330
rc = gpgme_get_engine_info(&engine_info);
331
if(rc != GPG_ERR_NO_ERROR){
332
fprintf_plus(stderr, "bad gpgme_get_engine_info: %s: %s\n",
333
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));
336
170
while(engine_info != NULL){
337
171
if(engine_info->protocol == GPGME_PROTOCOL_OpenPGP){
338
172
gpgme_set_engine_info(GPGME_PROTOCOL_OpenPGP,
339
engine_info->file_name, tempdir);
173
engine_info->file_name, homedir);
342
176
engine_info = engine_info->next;
344
178
if(engine_info == NULL){
345
fprintf_plus(stderr, "Could not set GPGME home dir to %s\n",
350
/* Create new GPGME "context" */
351
rc = gpgme_new(&(mc->ctx));
352
if(rc != GPG_ERR_NO_ERROR){
353
fprintf_plus(stderr, "Mandos plugin mandos-client: "
354
"bad gpgme_new: %s: %s\n", gpgme_strsource(rc),
359
if(not import_key(pubkey) or not import_key(seckey)){
367
* Decrypt OpenPGP data.
368
* Returns -1 on error
370
__attribute__((nonnull, warn_unused_result))
371
static ssize_t pgp_packet_decrypt(const char *cryptotext,
375
gpgme_data_t dh_crypto, dh_plain;
378
size_t plaintext_capacity = 0;
379
ssize_t plaintext_length = 0;
382
fprintf_plus(stderr, "Trying to decrypt OpenPGP data\n");
179
fprintf(stderr, "Could not set GPGME home dir to %s\n", homedir);
385
183
/* Create new GPGME data buffer from memory cryptotext */
386
184
rc = gpgme_data_new_from_mem(&dh_crypto, cryptotext, crypto_size,
388
if(rc != GPG_ERR_NO_ERROR){
389
fprintf_plus(stderr, "bad gpgme_data_new_from_mem: %s: %s\n",
390
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));
394
192
/* Create new empty GPGME data buffer for the plaintext */
395
193
rc = gpgme_data_new(&dh_plain);
396
if(rc != GPG_ERR_NO_ERROR){
397
fprintf_plus(stderr, "Mandos plugin mandos-client: "
398
"bad gpgme_data_new: %s: %s\n",
399
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));
400
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;
404
210
/* Decrypt data from the cryptotext data buffer to the plaintext
406
rc = gpgme_op_decrypt(mc->ctx, dh_crypto, dh_plain);
407
if(rc != GPG_ERR_NO_ERROR){
408
fprintf_plus(stderr, "bad gpgme_op_decrypt: %s: %s\n",
409
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));
410
216
plaintext_length = -1;
412
218
gpgme_decrypt_result_t result;
413
result = gpgme_op_decrypt_result(mc->ctx);
415
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");
417
fprintf_plus(stderr, "Unsupported algorithm: %s\n",
418
result->unsupported_algorithm);
419
fprintf_plus(stderr, "Wrong key usage: %u\n",
420
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);
421
227
if(result->file_name != NULL){
422
fprintf_plus(stderr, "File name: %s\n", result->file_name);
228
fprintf(stderr, "File name: %s\n", result->file_name);
424
230
gpgme_recipient_t recipient;
425
231
recipient = result->recipients;
426
while(recipient != NULL){
427
fprintf_plus(stderr, "Public key algorithm: %s\n",
428
gpgme_pubkey_algo_name
429
(recipient->pubkey_algo));
430
fprintf_plus(stderr, "Key ID: %s\n", recipient->keyid);
431
fprintf_plus(stderr, "Secret key available: %s\n",
432
recipient->status == GPG_ERR_NO_SECKEY
434
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;
820
434
static void empty_log(__attribute__((unused)) AvahiLogLevel level,
821
435
__attribute__((unused)) const char *txt){}
823
/* Set effective uid to 0, return errno */
824
__attribute__((warn_unused_result))
825
error_t raise_privileges(void){
826
error_t old_errno = errno;
827
error_t ret_errno = 0;
828
if(seteuid(0) == -1){
835
/* Set effective and real user ID to 0. Return errno. */
836
__attribute__((warn_unused_result))
837
error_t raise_privileges_permanently(void){
838
error_t old_errno = errno;
839
error_t ret_errno = raise_privileges();
851
/* Set effective user ID to unprivileged saved user ID */
852
__attribute__((warn_unused_result))
853
error_t lower_privileges(void){
854
error_t old_errno = errno;
855
error_t ret_errno = 0;
856
if(seteuid(uid) == -1){
863
/* Lower privileges permanently */
864
__attribute__((warn_unused_result))
865
error_t lower_privileges_permanently(void){
866
error_t old_errno = errno;
867
error_t ret_errno = 0;
868
if(setuid(uid) == -1){
875
/* Helper function to add_local_route() and delete_local_route() */
876
__attribute__((nonnull, warn_unused_result))
877
static bool add_delete_local_route(const bool add,
879
AvahiIfIndex if_index){
881
char helper[] = "mandos-client-iprouteadddel";
882
char add_arg[] = "add";
883
char delete_arg[] = "delete";
884
char debug_flag[] = "--debug";
885
char *pluginhelperdir = getenv("MANDOSPLUGINHELPERDIR");
886
if(pluginhelperdir == NULL){
888
fprintf_plus(stderr, "MANDOSPLUGINHELPERDIR environment"
889
" variable not set; cannot run helper\n");
894
char interface[IF_NAMESIZE];
895
if(if_indextoname((unsigned int)if_index, interface) == NULL){
896
perror_plus("if_indextoname");
900
int devnull = (int)TEMP_FAILURE_RETRY(open("/dev/null", O_RDONLY));
902
perror_plus("open(\"/dev/null\", O_RDONLY)");
908
/* Raise privileges */
909
errno = raise_privileges_permanently();
911
perror_plus("Failed to raise privileges");
912
/* _exit(EX_NOPERM); */
918
perror_plus("setgid");
921
/* Reset supplementary groups */
923
ret = setgroups(0, NULL);
925
perror_plus("setgroups");
929
ret = dup2(devnull, STDIN_FILENO);
931
perror_plus("dup2(devnull, STDIN_FILENO)");
934
ret = close(devnull);
936
perror_plus("close");
939
ret = dup2(STDERR_FILENO, STDOUT_FILENO);
941
perror_plus("dup2(STDERR_FILENO, STDOUT_FILENO)");
944
int helperdir_fd = (int)TEMP_FAILURE_RETRY(open(pluginhelperdir,
949
if(helperdir_fd == -1){
951
_exit(EX_UNAVAILABLE);
953
int helper_fd = (int)TEMP_FAILURE_RETRY(openat(helperdir_fd,
956
perror_plus("openat");
958
_exit(EX_UNAVAILABLE);
962
#pragma GCC diagnostic push
963
#pragma GCC diagnostic ignored "-Wcast-qual"
965
if(fexecve(helper_fd, (char *const [])
966
{ helper, add ? add_arg : delete_arg, (char *)address,
967
interface, debug ? debug_flag : NULL, NULL },
970
#pragma GCC diagnostic pop
972
perror_plus("fexecve");
984
pret = waitpid(pid, &status, 0);
985
if(pret == -1 and errno == EINTR and quit_now){
986
int errno_raising = 0;
987
if((errno = raise_privileges()) != 0){
988
errno_raising = errno;
989
perror_plus("Failed to raise privileges in order to"
990
" kill helper program");
992
if(kill(pid, SIGTERM) == -1){
995
if((errno_raising == 0) and (errno = lower_privileges()) != 0){
996
perror_plus("Failed to lower privileges after killing"
1001
} while(pret == -1 and errno == EINTR);
1003
perror_plus("waitpid");
1006
if(WIFEXITED(status)){
1007
if(WEXITSTATUS(status) != 0){
1008
fprintf_plus(stderr, "Error: iprouteadddel exited"
1009
" with status %d\n", WEXITSTATUS(status));
1014
if(WIFSIGNALED(status)){
1015
fprintf_plus(stderr, "Error: iprouteadddel died by"
1016
" signal %d\n", WTERMSIG(status));
1019
fprintf_plus(stderr, "Error: iprouteadddel crashed\n");
1023
__attribute__((nonnull, warn_unused_result))
1024
static bool add_local_route(const char *address,
1025
AvahiIfIndex if_index){
1027
fprintf_plus(stderr, "Adding route to %s\n", address);
1029
return add_delete_local_route(true, address, if_index);
1032
__attribute__((nonnull, warn_unused_result))
1033
static bool delete_local_route(const char *address,
1034
AvahiIfIndex if_index){
1036
fprintf_plus(stderr, "Removing route to %s\n", address);
1038
return add_delete_local_route(false, address, if_index);
1041
437
/* Called when a Mandos server is found */
1042
__attribute__((nonnull, warn_unused_result))
1043
static int start_mandos_communication(const char *ip, in_port_t port,
438
static int start_mandos_communication(const char *ip, uint16_t port,
1044
439
AvahiIfIndex if_index,
1045
int af, mandos_context *mc){
1046
int ret, tcp_sd = -1;
1048
struct sockaddr_storage to;
442
union { struct sockaddr in; struct sockaddr_in6 in6; } to;
1049
443
char *buffer = NULL;
1050
char *decrypted_buffer = NULL;
444
char *decrypted_buffer;
1051
445
size_t buffer_length = 0;
1052
446
size_t buffer_capacity = 0;
447
ssize_t decrypted_buffer_size;
450
char interface[IF_NAMESIZE];
1055
451
gnutls_session_t session;
1056
int pf; /* Protocol family */
1057
bool route_added = false;
1074
fprintf_plus(stderr, "Bad address family: %d\n", af);
1079
/* If the interface is specified and we have a list of interfaces */
1080
if(if_index != AVAHI_IF_UNSPEC and mc->interfaces != NULL){
1081
/* Check if the interface is one of the interfaces we are using */
1084
char *interface = NULL;
1085
while((interface=argz_next(mc->interfaces, mc->interfaces_size,
1087
if(if_nametoindex(interface) == (unsigned int)if_index){
1094
/* This interface does not match any in the list, so we don't
1095
connect to the server */
1097
char interface[IF_NAMESIZE];
1098
if(if_indextoname((unsigned int)if_index, interface) == NULL){
1099
perror_plus("if_indextoname");
1101
fprintf_plus(stderr, "Skipping server on non-used interface"
1103
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);
1111
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);
1117
fprintf_plus(stderr, "Setting up a TCP connection to %s, port %"
1118
PRIuMAX "\n", ip, (uintmax_t)port);
1121
tcp_sd = socket(pf, SOCK_STREAM | SOCK_CLOEXEC, 0);
1124
perror_plus("socket");
1135
struct sockaddr_in6 *to6 = (struct sockaddr_in6 *)&to;
1136
*to6 = (struct sockaddr_in6){ .sin6_family = (sa_family_t)af };
1137
ret = inet_pton(af, ip, &to6->sin6_addr);
1139
struct sockaddr_in *to4 = (struct sockaddr_in *)&to;
1140
*to4 = (struct sockaddr_in){ .sin_family = (sa_family_t)af };
1141
ret = inet_pton(af, ip, &to4->sin_addr);
1145
perror_plus("inet_pton");
1151
fprintf_plus(stderr, "Bad address: %s\n", ip);
1156
((struct sockaddr_in6 *)&to)->sin6_port = htons(port);
1157
if(IN6_IS_ADDR_LINKLOCAL
1158
(&((struct sockaddr_in6 *)&to)->sin6_addr)){
1159
if(if_index == AVAHI_IF_UNSPEC){
1160
fprintf_plus(stderr, "An IPv6 link-local address is"
1161
" incomplete without a network interface\n");
1165
/* Set the network interface number as scope */
1166
((struct sockaddr_in6 *)&to)->sin6_scope_id = (uint32_t)if_index;
1169
((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;
1178
if(af == AF_INET6 and if_index != AVAHI_IF_UNSPEC){
1179
char interface[IF_NAMESIZE];
1180
if(if_indextoname((unsigned int)if_index, interface) == NULL){
1181
perror_plus("if_indextoname");
1183
fprintf_plus(stderr, "Connection to: %s%%%s, port %" PRIuMAX
1184
"\n", ip, interface, (uintmax_t)port);
1187
fprintf_plus(stderr, "Connection to: %s, port %" PRIuMAX "\n",
1188
ip, (uintmax_t)port);
1190
char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?
1191
INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";
1193
ret = getnameinfo((struct sockaddr *)&to,
1194
sizeof(struct sockaddr_in6),
1195
addrstr, sizeof(addrstr), NULL, 0,
1198
ret = getnameinfo((struct sockaddr *)&to,
1199
sizeof(struct sockaddr_in),
1200
addrstr, sizeof(addrstr), NULL, 0,
1203
if(ret == EAI_SYSTEM){
1204
perror_plus("getnameinfo");
1205
} else if(ret != 0) {
1206
fprintf_plus(stderr, "getnameinfo: %s", gai_strerror(ret));
1207
} else if(strcmp(addrstr, ip) != 0){
1208
fprintf_plus(stderr, "Canonical address form: %s\n", addrstr);
1219
ret = connect(tcp_sd, (struct sockaddr *)&to,
1220
sizeof(struct sockaddr_in6));
1222
ret = connect(tcp_sd, (struct sockaddr *)&to, /* IPv4 */
1223
sizeof(struct sockaddr_in));
1226
if(errno == ENETUNREACH
1227
and if_index != AVAHI_IF_UNSPEC
1228
and connect_to == NULL
1229
and not route_added and
1230
((af == AF_INET6 and not
1231
IN6_IS_ADDR_LINKLOCAL(&(((struct sockaddr_in6 *)
1233
or (af == AF_INET and
1234
/* Not a a IPv4LL address */
1235
(ntohl(((struct sockaddr_in *)&to)->sin_addr.s_addr)
1236
& 0xFFFF0000L) != 0xA9FE0000L))){
1237
/* Work around Avahi bug - Avahi does not announce link-local
1238
addresses if it has a global address, so local hosts with
1239
*only* a link-local address (e.g. Mandos clients) cannot
1240
connect to a Mandos server announced by Avahi on a server
1241
host with a global address. Work around this by retrying
1242
with an explicit route added with the server's address.
1244
Avahi bug reference:
1245
http://lists.freedesktop.org/archives/avahi/2010-February/001833.html
1246
https://bugs.debian.org/587961
1249
fprintf_plus(stderr, "Mandos server unreachable, trying"
1253
route_added = add_local_route(ip, if_index);
1259
if(errno != ECONNREFUSED or debug){
1261
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));
1274
514
const char *out = mandos_protocol_version;
1277
517
size_t out_size = strlen(out);
1278
ret = (int)TEMP_FAILURE_RETRY(write(tcp_sd, out + written,
1279
out_size - written));
1282
perror_plus("write");
518
ret = TEMP_FAILURE_RETRY(write(tcp_sd, out + written,
519
out_size - written));
1284
523
goto mandos_end;
1286
525
written += (size_t)ret;
1287
526
if(written < out_size){
1290
if(out == mandos_protocol_version){
529
if (out == mandos_protocol_version){
1305
fprintf_plus(stderr, "Establishing TLS session with %s\n", ip);
1313
/* This casting via intptr_t is to eliminate warning about casting
1314
an int to a pointer type. This is exactly how the GnuTLS Guile
1315
function "set-session-transport-fd!" does it. */
1316
gnutls_transport_set_ptr(session,
1317
(gnutls_transport_ptr_t)(intptr_t)tcp_sd);
1325
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);
1330
546
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
1332
if(ret != GNUTLS_E_SUCCESS){
548
if (ret != GNUTLS_E_SUCCESS){
1334
fprintf_plus(stderr, "*** GnuTLS Handshake failed ***\n");
550
fprintf(stderr, "*** GnuTLS Handshake failed ***\n");
1338
554
goto mandos_end;
1341
557
/* Read OpenPGP packet that contains the wanted password */
1344
fprintf_plus(stderr, "Retrieving OpenPGP encrypted password from"
560
fprintf(stderr, "Retrieving pgp encrypted password from %s\n",
1355
buffer_capacity = incbuffer(&buffer, buffer_length,
1357
if(buffer_capacity == 0){
1359
perror_plus("incbuffer");
1369
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,
1376
580
case GNUTLS_E_INTERRUPTED:
1377
581
case GNUTLS_E_AGAIN:
1379
583
case GNUTLS_E_REHANDSHAKE:
1381
ret = gnutls_handshake(session);
585
ret = gnutls_handshake (session);
1387
586
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
1389
fprintf_plus(stderr, "*** GnuTLS Re-handshake failed "
588
fprintf(stderr, "*** GnuTLS Re-handshake failed ***\n");
1393
591
goto mandos_end;
1397
fprintf_plus(stderr, "Unknown error while reading data from"
1398
" encrypted session with Mandos server\n");
1399
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);
1401
599
goto mandos_end;
1404
buffer_length += (size_t) sret;
602
buffer_length += (size_t) ret;
1409
fprintf_plus(stderr, "Closing TLS session\n");
1418
ret = gnutls_bye(session, GNUTLS_SHUT_RDWR);
1423
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
1425
if(buffer_length > 0){
1426
ssize_t decrypted_buffer_size;
1427
decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,
1428
&decrypted_buffer, mc);
1429
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;
633
free(decrypted_buffer);
1456
641
/* Shutdown procedure */
1461
if(not delete_local_route(ip, if_index)){
1462
fprintf_plus(stderr, "Failed to delete local route to %s on"
1463
" interface %d", ip, if_index);
1467
free(decrypted_buffer);
1470
ret = close(tcp_sd);
1476
perror_plus("close");
1478
gnutls_deinit(session);
646
gnutls_deinit (session);
1488
__attribute__((nonnull))
1489
650
static void resolve_callback(AvahiSServiceResolver *r,
1490
651
AvahiIfIndex interface,
1491
AvahiProtocol proto,
652
AVAHI_GCC_UNUSED AvahiProtocol protocol,
1492
653
AvahiResolverEvent event,
1493
654
const char *name,
1494
655
const char *type,
1603
738
case AVAHI_BROWSER_ALL_FOR_NOW:
1604
739
case AVAHI_BROWSER_CACHE_EXHAUSTED:
1606
fprintf_plus(stderr, "No Mandos server found, still"
741
fprintf(stderr, "No Mandos server found, still searching...\n");
1613
/* Signal handler that stops main loop after SIGTERM */
1614
static void handle_sigterm(int sig){
1619
signal_received = sig;
1620
int old_errno = errno;
1621
/* set main loop to exit */
1622
if(simple_poll != NULL){
1623
avahi_simple_poll_quit(simple_poll);
1628
__attribute__((nonnull, warn_unused_result))
1629
bool get_flags(const char *ifname, struct ifreq *ifr){
1633
int s = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1636
perror_plus("socket");
1640
strcpy(ifr->ifr_name, ifname);
1641
ret = ioctl(s, SIOCGIFFLAGS, ifr);
1645
perror_plus("ioctl SIOCGIFFLAGS");
1653
__attribute__((nonnull, warn_unused_result))
1654
bool good_flags(const char *ifname, const struct ifreq *ifr){
1656
/* Reject the loopback device */
1657
if(ifr->ifr_flags & IFF_LOOPBACK){
1659
fprintf_plus(stderr, "Rejecting loopback interface \"%s\"\n",
1664
/* Accept point-to-point devices only if connect_to is specified */
1665
if(connect_to != NULL and (ifr->ifr_flags & IFF_POINTOPOINT)){
1667
fprintf_plus(stderr, "Accepting point-to-point interface"
1668
" \"%s\"\n", ifname);
1672
/* Otherwise, reject non-broadcast-capable devices */
1673
if(not (ifr->ifr_flags & IFF_BROADCAST)){
1675
fprintf_plus(stderr, "Rejecting non-broadcast interface"
1676
" \"%s\"\n", ifname);
1680
/* Reject non-ARP interfaces (including dummy interfaces) */
1681
if(ifr->ifr_flags & IFF_NOARP){
1683
fprintf_plus(stderr, "Rejecting non-ARP interface \"%s\"\n",
1689
/* Accept this device */
1691
fprintf_plus(stderr, "Interface \"%s\" is good\n", ifname);
1697
* This function determines if a directory entry in /sys/class/net
1698
* corresponds to an acceptable network device.
1699
* (This function is passed to scandir(3) as a filter function.)
1701
__attribute__((nonnull, warn_unused_result))
1702
int good_interface(const struct dirent *if_entry){
1703
if(if_entry->d_name[0] == '.'){
1708
if(not get_flags(if_entry->d_name, &ifr)){
1710
fprintf_plus(stderr, "Failed to get flags for interface "
1711
"\"%s\"\n", if_entry->d_name);
1716
if(not good_flags(if_entry->d_name, &ifr)){
1723
* This function determines if a network interface is up.
1725
__attribute__((nonnull, warn_unused_result))
1726
bool interface_is_up(const char *interface){
1728
if(not get_flags(interface, &ifr)){
1730
fprintf_plus(stderr, "Failed to get flags for interface "
1731
"\"%s\"\n", interface);
1736
return (bool)(ifr.ifr_flags & IFF_UP);
1740
* This function determines if a network interface is running
1742
__attribute__((nonnull, warn_unused_result))
1743
bool interface_is_running(const char *interface){
1745
if(not get_flags(interface, &ifr)){
1747
fprintf_plus(stderr, "Failed to get flags for interface "
1748
"\"%s\"\n", interface);
1753
return (bool)(ifr.ifr_flags & IFF_RUNNING);
1756
__attribute__((nonnull, pure, warn_unused_result))
1757
int notdotentries(const struct dirent *direntry){
1758
/* Skip "." and ".." */
1759
if(direntry->d_name[0] == '.'
1760
and (direntry->d_name[1] == '\0'
1761
or (direntry->d_name[1] == '.'
1762
and direntry->d_name[2] == '\0'))){
1768
/* Is this directory entry a runnable program? */
1769
__attribute__((nonnull, warn_unused_result))
1770
int runnable_hook(const struct dirent *direntry){
1775
if((direntry->d_name)[0] == '\0'){
1780
sret = strspn(direntry->d_name, "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
1781
"abcdefghijklmnopqrstuvwxyz"
1784
if((direntry->d_name)[sret] != '\0'){
1785
/* Contains non-allowed characters */
1787
fprintf_plus(stderr, "Ignoring hook \"%s\" with bad name\n",
1793
ret = fstatat(hookdir_fd, direntry->d_name, &st, 0);
1796
perror_plus("Could not stat hook");
1800
if(not (S_ISREG(st.st_mode))){
1801
/* Not a regular file */
1803
fprintf_plus(stderr, "Ignoring hook \"%s\" - not a file\n",
1808
if(not (st.st_mode & (S_IXUSR | S_IXGRP | S_IXOTH))){
1809
/* Not executable */
1811
fprintf_plus(stderr, "Ignoring hook \"%s\" - not executable\n",
1817
fprintf_plus(stderr, "Hook \"%s\" is acceptable\n",
1823
__attribute__((nonnull, warn_unused_result))
1824
int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,
1825
mandos_context *mc){
1827
struct timespec now;
1828
struct timespec waited_time;
1829
intmax_t block_time;
1832
if(mc->current_server == NULL){
1834
fprintf_plus(stderr, "Wait until first server is found."
1837
ret = avahi_simple_poll_iterate(s, -1);
1840
fprintf_plus(stderr, "Check current_server if we should run"
1843
/* the current time */
1844
ret = clock_gettime(CLOCK_MONOTONIC, &now);
1846
perror_plus("clock_gettime");
1849
/* Calculating in ms how long time between now and server
1850
who we visted longest time ago. Now - last seen. */
1851
waited_time.tv_sec = (now.tv_sec
1852
- mc->current_server->last_seen.tv_sec);
1853
waited_time.tv_nsec = (now.tv_nsec
1854
- mc->current_server->last_seen.tv_nsec);
1855
/* total time is 10s/10,000ms.
1856
Converting to s from ms by dividing by 1,000,
1857
and ns to ms by dividing by 1,000,000. */
1858
block_time = ((retry_interval
1859
- ((intmax_t)waited_time.tv_sec * 1000))
1860
- ((intmax_t)waited_time.tv_nsec / 1000000));
1863
fprintf_plus(stderr, "Blocking for %" PRIdMAX " ms\n",
1867
if(block_time <= 0){
1868
ret = start_mandos_communication(mc->current_server->ip,
1869
mc->current_server->port,
1870
mc->current_server->if_index,
1871
mc->current_server->af, mc);
1873
avahi_simple_poll_quit(s);
1876
ret = clock_gettime(CLOCK_MONOTONIC,
1877
&mc->current_server->last_seen);
1879
perror_plus("clock_gettime");
1882
mc->current_server = mc->current_server->next;
1883
block_time = 0; /* Call avahi to find new Mandos
1884
servers, but don't block */
1887
ret = avahi_simple_poll_iterate(s, (int)block_time);
1890
if(ret > 0 or errno != EINTR){
1891
return (ret != 1) ? ret : 0;
1897
__attribute__((nonnull))
1898
void run_network_hooks(const char *mode, const char *interface,
1900
struct dirent **direntries = NULL;
1901
if(hookdir_fd == -1){
1902
hookdir_fd = open(hookdir, O_RDONLY | O_DIRECTORY | O_PATH
1904
if(hookdir_fd == -1){
1905
if(errno == ENOENT){
1907
fprintf_plus(stderr, "Network hook directory \"%s\" not"
1908
" found\n", hookdir);
1911
perror_plus("open");
1917
#if __GLIBC_PREREQ(2, 15)
1918
int numhooks = scandirat(hookdir_fd, ".", &direntries,
1919
runnable_hook, alphasort);
1920
#else /* not __GLIBC_PREREQ(2, 15) */
1921
int numhooks = scandir(hookdir, &direntries, runnable_hook,
1923
#endif /* not __GLIBC_PREREQ(2, 15) */
1924
#else /* not __GLIBC__ */
1925
int numhooks = scandir(hookdir, &direntries, runnable_hook,
1927
#endif /* not __GLIBC__ */
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
error_t bring_up_interface(const char *const interface,
2090
error_t 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)){
2106
error_t ret_errno = 0, ioctl_errno = 0;
2107
if(not get_flags(interface, &network)){
2109
fprintf_plus(stderr, "Failed to get flags for interface "
2110
"\"%s\"\n", interface);
2114
network.ifr_flags |= IFF_UP; /* set flag */
2116
int sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
2119
perror_plus("socket");
2127
perror_plus("close");
2134
fprintf_plus(stderr, "Bringing up interface \"%s\"\n",
2138
/* Raise privileges */
2139
ret_errno = raise_privileges();
2142
perror_plus("Failed to raise privileges");
2147
bool restore_loglevel = false;
2149
/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO
2150
messages about the network interface to mess up the prompt */
2151
ret_linux = klogctl(8, NULL, 5);
2152
if(ret_linux == -1){
2153
perror_plus("klogctl");
2155
restore_loglevel = true;
2158
#endif /* __linux__ */
2159
int ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
2160
ioctl_errno = errno;
2162
if(restore_loglevel){
2163
ret_linux = klogctl(7, NULL, 0);
2164
if(ret_linux == -1){
2165
perror_plus("klogctl");
2168
#endif /* __linux__ */
2170
/* If raise_privileges() succeeded above */
2172
/* Lower privileges */
2173
ret_errno = lower_privileges();
2176
perror_plus("Failed to lower privileges");
2180
/* Close the socket */
2183
perror_plus("close");
2186
if(ret_setflags == -1){
2187
errno = ioctl_errno;
2188
perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");
2193
fprintf_plus(stderr, "Interface \"%s\" is already up; good\n",
2197
/* Sleep checking until interface is running.
2198
Check every 0.25s, up to total time of delay */
2199
for(int i=0; i < delay * 4; i++){
2200
if(interface_is_running(interface)){
2203
struct timespec sleeptime = { .tv_nsec = 250000000 };
2204
ret = nanosleep(&sleeptime, NULL);
2205
if(ret == -1 and errno != EINTR){
2206
perror_plus("nanosleep");
2214
__attribute__((nonnull, warn_unused_result))
2215
error_t take_down_interface(const char *const interface){
2216
error_t old_errno = errno;
2217
struct ifreq network;
2218
unsigned int if_index = if_nametoindex(interface);
2220
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
2224
if(interface_is_up(interface)){
2225
error_t ret_errno = 0, ioctl_errno = 0;
2226
if(not get_flags(interface, &network) and debug){
2228
fprintf_plus(stderr, "Failed to get flags for interface "
2229
"\"%s\"\n", interface);
2233
network.ifr_flags &= ~(short)IFF_UP; /* clear flag */
2235
int sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
2238
perror_plus("socket");
2244
fprintf_plus(stderr, "Taking down interface \"%s\"\n",
2248
/* Raise privileges */
2249
ret_errno = raise_privileges();
2252
perror_plus("Failed to raise privileges");
2255
int ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
2256
ioctl_errno = errno;
2258
/* If raise_privileges() succeeded above */
2260
/* Lower privileges */
2261
ret_errno = lower_privileges();
2264
perror_plus("Failed to lower privileges");
2268
/* Close the socket */
2269
int ret = close(sd);
2271
perror_plus("close");
2274
if(ret_setflags == -1){
2275
errno = ioctl_errno;
2276
perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");
2281
fprintf_plus(stderr, "Interface \"%s\" is already 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);
2289
759
int main(int argc, char *argv[]){
2290
mandos_context mc = { .server = NULL, .dh_bits = 0,
2291
.priority = "SECURE256:!CTYPE-X.509"
2292
":+CTYPE-OPENPGP:!RSA:+SIGN-DSA-SHA256",
2293
.current_server = NULL, .interfaces = NULL,
2294
.interfaces_size = 0 };
2295
AvahiSServiceBrowser *sb = NULL;
2300
int exitcode = EXIT_SUCCESS;
2301
char *interfaces_to_take_down = NULL;
2302
size_t interfaces_to_take_down_size = 0;
2303
char run_tempdir[] = "/run/tmp/mandosXXXXXX";
2304
char old_tempdir[] = "/tmp/mandosXXXXXX";
2305
char *tempdir = NULL;
2306
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
2307
const char *seckey = PATHDIR "/" SECKEY;
2308
const char *pubkey = PATHDIR "/" PUBKEY;
2309
const char *dh_params_file = NULL;
2310
char *interfaces_hooks = NULL;
2312
bool gnutls_initialized = false;
2313
bool gpgme_initialized = false;
2315
double retry_interval = 10; /* 10s between trying a server and
2316
retrying the same server again */
2318
struct sigaction old_sigterm_action = { .sa_handler = SIG_DFL };
2319
struct sigaction sigterm_action = { .sa_handler = handle_sigterm };
2324
/* Lower any group privileges we might have, just to be safe */
2328
perror_plus("setgid");
2331
/* Lower user privileges (temporarily) */
2335
perror_plus("seteuid");
2343
struct argp_option options[] = {
2344
{ .name = "debug", .key = 128,
2345
.doc = "Debug mode", .group = 3 },
2346
{ .name = "connect", .key = 'c',
2347
.arg = "ADDRESS:PORT",
2348
.doc = "Connect directly to a specific Mandos server",
2350
{ .name = "interface", .key = 'i',
2352
.doc = "Network interface that will be used to search for"
2355
{ .name = "seckey", .key = 's',
2357
.doc = "OpenPGP secret key file base name",
2359
{ .name = "pubkey", .key = 'p',
2361
.doc = "OpenPGP public key file base name",
2363
{ .name = "dh-bits", .key = 129,
2365
.doc = "Bit length of the prime number used in the"
2366
" Diffie-Hellman key exchange",
2368
{ .name = "dh-params", .key = 134,
2370
.doc = "PEM-encoded PKCS#3 file with pre-generated parameters"
2371
" for the Diffie-Hellman key exchange",
2373
{ .name = "priority", .key = 130,
2375
.doc = "GnuTLS priority string for the TLS handshake",
2377
{ .name = "delay", .key = 131,
2379
.doc = "Maximum delay to wait for interface startup",
2381
{ .name = "retry", .key = 132,
2383
.doc = "Retry interval used when denied by the Mandos server",
2385
{ .name = "network-hook-dir", .key = 133,
2387
.doc = "Directory where network hooks are located",
2390
* These reproduce what we would get without ARGP_NO_HELP
2392
{ .name = "help", .key = '?',
2393
.doc = "Give this help list", .group = -1 },
2394
{ .name = "usage", .key = -3,
2395
.doc = "Give a short usage message", .group = -1 },
2396
{ .name = "version", .key = 'V',
2397
.doc = "Print program version", .group = -1 },
2401
error_t parse_opt(int key, char *arg,
2402
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;
2405
case 128: /* --debug */
2408
case 'c': /* --connect */
2411
case 'i': /* --interface */
2412
ret_errno = argz_add_sep(&mc.interfaces, &mc.interfaces_size,
2415
argp_error(state, "%s", strerror(ret_errno));
2418
case 's': /* --seckey */
2421
case 'p': /* --pubkey */
2424
case 129: /* --dh-bits */
2426
tmpmax = strtoimax(arg, &tmp, 10);
2427
if(errno != 0 or tmp == arg or *tmp != '\0'
2428
or tmpmax != (typeof(mc.dh_bits))tmpmax){
2429
argp_error(state, "Bad number of DH bits");
2431
mc.dh_bits = (typeof(mc.dh_bits))tmpmax;
2433
case 134: /* --dh-params */
2434
dh_params_file = arg;
2436
case 130: /* --priority */
2439
case 131: /* --delay */
2441
delay = strtof(arg, &tmp);
2442
if(errno != 0 or tmp == arg or *tmp != '\0'){
2443
argp_error(state, "Bad delay");
2445
case 132: /* --retry */
2447
retry_interval = strtod(arg, &tmp);
2448
if(errno != 0 or tmp == arg or *tmp != '\0'
2449
or (retry_interval * 1000) > INT_MAX
2450
or retry_interval < 0){
2451
argp_error(state, "Bad retry interval");
2454
case 133: /* --network-hook-dir */
2458
* These reproduce what we would get without ARGP_NO_HELP
2460
case '?': /* --help */
2461
argp_state_help(state, state->out_stream,
2462
(ARGP_HELP_STD_HELP | ARGP_HELP_EXIT_ERR)
2463
& ~(unsigned int)ARGP_HELP_EXIT_OK);
2464
case -3: /* --usage */
2465
argp_state_help(state, state->out_stream,
2466
ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);
2467
case 'V': /* --version */
2468
fprintf_plus(state->out_stream, "%s\n", argp_program_version);
2469
exit(argp_err_exit_status);
2472
return ARGP_ERR_UNKNOWN;
2477
struct argp argp = { .options = options, .parser = parse_opt,
2479
.doc = "Mandos client -- Get and decrypt"
2480
" passwords from a Mandos server" };
2481
ret = argp_parse(&argp, argc, argv,
2482
ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);
2489
perror_plus("argp_parse");
2490
exitcode = EX_OSERR;
2493
exitcode = EX_USAGE;
2499
/* Work around Debian bug #633582:
2500
<http://bugs.debian.org/633582> */
2502
/* Re-raise privileges */
2503
ret_errno = raise_privileges();
2506
perror_plus("Failed to raise privileges");
2510
if(strcmp(seckey, PATHDIR "/" SECKEY) == 0){
2511
int seckey_fd = open(seckey, O_RDONLY);
2512
if(seckey_fd == -1){
2513
perror_plus("open");
2515
ret = (int)TEMP_FAILURE_RETRY(fstat(seckey_fd, &st));
2517
perror_plus("fstat");
2519
if(S_ISREG(st.st_mode)
2520
and st.st_uid == 0 and st.st_gid == 0){
2521
ret = fchown(seckey_fd, uid, gid);
2523
perror_plus("fchown");
2531
if(strcmp(pubkey, PATHDIR "/" PUBKEY) == 0){
2532
int pubkey_fd = open(pubkey, O_RDONLY);
2533
if(pubkey_fd == -1){
2534
perror_plus("open");
2536
ret = (int)TEMP_FAILURE_RETRY(fstat(pubkey_fd, &st));
2538
perror_plus("fstat");
2540
if(S_ISREG(st.st_mode)
2541
and st.st_uid == 0 and st.st_gid == 0){
2542
ret = fchown(pubkey_fd, uid, gid);
2544
perror_plus("fchown");
2552
if(dh_params_file != NULL
2553
and strcmp(dh_params_file, PATHDIR "/dhparams.pem" ) == 0){
2554
int dhparams_fd = open(dh_params_file, O_RDONLY);
2555
if(dhparams_fd == -1){
2556
perror_plus("open");
2558
ret = (int)TEMP_FAILURE_RETRY(fstat(dhparams_fd, &st));
2560
perror_plus("fstat");
2562
if(S_ISREG(st.st_mode)
2563
and st.st_uid == 0 and st.st_gid == 0){
2564
ret = fchown(dhparams_fd, uid, gid);
2566
perror_plus("fchown");
2574
/* Lower privileges */
2575
ret_errno = lower_privileges();
2578
perror_plus("Failed to lower privileges");
2583
/* Remove invalid interface names (except "none") */
2585
char *interface = NULL;
2586
while((interface = argz_next(mc.interfaces, mc.interfaces_size,
2588
if(strcmp(interface, "none") != 0
2589
and if_nametoindex(interface) == 0){
2590
if(interface[0] != '\0'){
2591
fprintf_plus(stderr, "Not using nonexisting interface"
2592
" \"%s\"\n", interface);
2594
argz_delete(&mc.interfaces, &mc.interfaces_size, interface);
2600
/* Run network hooks */
2602
if(mc.interfaces != NULL){
2603
interfaces_hooks = malloc(mc.interfaces_size);
2604
if(interfaces_hooks == NULL){
2605
perror_plus("malloc");
952
uint16_t port = (uint16_t) strtol(address+1, NULL, 10);
954
perror("Bad port number");
955
exitcode = EXIT_FAILURE;
2608
memcpy(interfaces_hooks, mc.interfaces, mc.interfaces_size);
2609
argz_stringify(interfaces_hooks, mc.interfaces_size, (int)',');
2611
run_network_hooks("start", interfaces_hooks != NULL ?
2612
interfaces_hooks : "", delay);
2616
avahi_set_log_function(empty_log);
2619
/* Initialize Avahi early so avahi_simple_poll_quit() can be called
2620
from the signal handler */
2621
/* Initialize the pseudo-RNG for Avahi */
2622
srand((unsigned int) time(NULL));
2623
simple_poll = avahi_simple_poll_new();
2624
if(simple_poll == NULL){
2625
fprintf_plus(stderr,
2626
"Avahi: Failed to create simple poll object.\n");
2627
exitcode = EX_UNAVAILABLE;
2631
sigemptyset(&sigterm_action.sa_mask);
2632
ret = sigaddset(&sigterm_action.sa_mask, SIGINT);
2634
perror_plus("sigaddset");
2635
exitcode = EX_OSERR;
2638
ret = sigaddset(&sigterm_action.sa_mask, SIGHUP);
2640
perror_plus("sigaddset");
2641
exitcode = EX_OSERR;
2644
ret = sigaddset(&sigterm_action.sa_mask, SIGTERM);
2646
perror_plus("sigaddset");
2647
exitcode = EX_OSERR;
2650
/* Need to check if the handler is SIG_IGN before handling:
2651
| [[info:libc:Initial Signal Actions]] |
2652
| [[info:libc:Basic Signal Handling]] |
2654
ret = sigaction(SIGINT, NULL, &old_sigterm_action);
2656
perror_plus("sigaction");
2659
if(old_sigterm_action.sa_handler != SIG_IGN){
2660
ret = sigaction(SIGINT, &sigterm_action, NULL);
2662
perror_plus("sigaction");
2663
exitcode = EX_OSERR;
2667
ret = sigaction(SIGHUP, NULL, &old_sigterm_action);
2669
perror_plus("sigaction");
2672
if(old_sigterm_action.sa_handler != SIG_IGN){
2673
ret = sigaction(SIGHUP, &sigterm_action, NULL);
2675
perror_plus("sigaction");
2676
exitcode = EX_OSERR;
2680
ret = sigaction(SIGTERM, NULL, &old_sigterm_action);
2682
perror_plus("sigaction");
2685
if(old_sigterm_action.sa_handler != SIG_IGN){
2686
ret = sigaction(SIGTERM, &sigterm_action, NULL);
2688
perror_plus("sigaction");
2689
exitcode = EX_OSERR;
2694
/* If no interfaces were specified, make a list */
2695
if(mc.interfaces == NULL){
2696
struct dirent **direntries = NULL;
2697
/* Look for any good interfaces */
2698
ret = scandir(sys_class_net, &direntries, good_interface,
2701
/* Add all found interfaces to interfaces list */
2702
for(int i = 0; i < ret; ++i){
2703
ret_errno = argz_add(&mc.interfaces, &mc.interfaces_size,
2704
direntries[i]->d_name);
2707
perror_plus("argz_add");
2708
free(direntries[i]);
2712
fprintf_plus(stderr, "Will use interface \"%s\"\n",
2713
direntries[i]->d_name);
2715
free(direntries[i]);
2722
fprintf_plus(stderr, "Could not find a network interface\n");
2723
exitcode = EXIT_FAILURE;
2728
/* Bring up interfaces which are down, and remove any "none"s */
2730
char *interface = NULL;
2731
while((interface = argz_next(mc.interfaces, mc.interfaces_size,
2733
/* If interface name is "none", stop bringing up interfaces.
2734
Also remove all instances of "none" from the list */
2735
if(strcmp(interface, "none") == 0){
2736
argz_delete(&mc.interfaces, &mc.interfaces_size,
2739
while((interface = argz_next(mc.interfaces,
2740
mc.interfaces_size, interface))){
2741
if(strcmp(interface, "none") == 0){
2742
argz_delete(&mc.interfaces, &mc.interfaces_size,
2749
bool interface_was_up = interface_is_up(interface);
2750
errno = bring_up_interface(interface, delay);
2751
if(not interface_was_up){
2753
fprintf_plus(stderr, "Failed to bring up interface \"%s\":"
2754
" %s\n", interface, strerror(errno));
2756
errno = argz_add(&interfaces_to_take_down,
2757
&interfaces_to_take_down_size,
2760
perror_plus("argz_add");
2765
if(debug and (interfaces_to_take_down == NULL)){
2766
fprintf_plus(stderr, "No interfaces were brought up\n");
2770
/* If we only got one interface, explicitly use only that one */
2771
if(argz_count(mc.interfaces, mc.interfaces_size) == 1){
2773
fprintf_plus(stderr, "Using only interface \"%s\"\n",
2776
if_index = (AvahiIfIndex)if_nametoindex(mc.interfaces);
2783
ret = init_gnutls_global(pubkey, seckey, dh_params_file, &mc);
2785
fprintf_plus(stderr, "init_gnutls_global failed\n");
2786
exitcode = EX_UNAVAILABLE;
2789
gnutls_initialized = true;
2796
/* Try /run/tmp before /tmp */
2797
tempdir = mkdtemp(run_tempdir);
2798
if(tempdir == NULL and errno == ENOENT){
2800
fprintf_plus(stderr, "Tempdir %s did not work, trying %s\n",
2801
run_tempdir, old_tempdir);
2803
tempdir = mkdtemp(old_tempdir);
2805
if(tempdir == NULL){
2806
perror_plus("mkdtemp");
2814
if(not init_gpgme(pubkey, seckey, tempdir, &mc)){
2815
fprintf_plus(stderr, "init_gpgme failed\n");
2816
exitcode = EX_UNAVAILABLE;
2819
gpgme_initialized = true;
2826
if(connect_to != NULL){
2827
/* Connect directly, do not use Zeroconf */
2828
/* (Mainly meant for debugging) */
2829
char *address = strrchr(connect_to, ':');
2831
if(address == NULL){
2832
fprintf_plus(stderr, "No colon in address\n");
2833
exitcode = EX_USAGE;
2843
tmpmax = strtoimax(address+1, &tmp, 10);
2844
if(errno != 0 or tmp == address+1 or *tmp != '\0'
2845
or tmpmax != (in_port_t)tmpmax){
2846
fprintf_plus(stderr, "Bad port number\n");
2847
exitcode = EX_USAGE;
2855
port = (in_port_t)tmpmax;
2857
/* Colon in address indicates IPv6 */
2859
if(strchr(connect_to, ':') != NULL){
2861
/* Accept [] around IPv6 address - see RFC 5952 */
2862
if(connect_to[0] == '[' and address[-1] == ']')
2870
address = connect_to;
2876
while(not quit_now){
2877
ret = start_mandos_communication(address, port, if_index, af,
2879
if(quit_now or ret == 0){
2883
fprintf_plus(stderr, "Retrying in %d seconds\n",
2884
(int)retry_interval);
2886
sleep((unsigned int)retry_interval);
2890
exitcode = EXIT_SUCCESS;
2901
AvahiServerConfig config;
2902
/* Do not publish any local Zeroconf records */
2903
avahi_server_config_init(&config);
2904
config.publish_hinfo = 0;
2905
config.publish_addresses = 0;
2906
config.publish_workstation = 0;
2907
config.publish_domain = 0;
2909
/* Allocate a new server */
2910
mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),
2911
&config, NULL, NULL, &ret_errno);
2913
/* Free the Avahi configuration data */
2914
avahi_server_config_free(&config);
2917
/* Check if creating the Avahi server object succeeded */
2918
if(mc.server == NULL){
2919
fprintf_plus(stderr, "Failed to create Avahi server: %s\n",
2920
avahi_strerror(ret_errno));
2921
exitcode = EX_UNAVAILABLE;
2929
/* Create the Avahi service browser */
2930
sb = avahi_s_service_browser_new(mc.server, if_index,
2931
AVAHI_PROTO_UNSPEC, "_mandos._tcp",
2932
NULL, 0, browse_callback,
2935
fprintf_plus(stderr, "Failed to create service browser: %s\n",
2936
avahi_strerror(avahi_server_errno(mc.server)));
2937
exitcode = EX_UNAVAILABLE;
2945
/* Run the main loop */
2948
fprintf_plus(stderr, "Starting Avahi loop search\n");
2951
ret = avahi_loop_with_timeout(simple_poll,
2952
(int)(retry_interval * 1000), &mc);
2954
fprintf_plus(stderr, "avahi_loop_with_timeout exited %s\n",
2955
(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);
2961
fprintf_plus(stderr, "%s exiting\n", argv[0]);
2964
/* Cleanup things */
2965
free(mc.interfaces);
2968
avahi_s_service_browser_free(sb);
2970
if(mc.server != NULL)
2971
avahi_server_free(mc.server);
2973
if(simple_poll != NULL)
2974
avahi_simple_poll_free(simple_poll);
2976
if(gnutls_initialized){
2977
gnutls_certificate_free_credentials(mc.cred);
2978
gnutls_global_deinit();
2979
gnutls_dh_params_deinit(mc.dh_params);
2982
if(gpgme_initialized){
2983
gpgme_release(mc.ctx);
2986
/* Cleans up the circular linked list of Mandos servers the client
2988
if(mc.current_server != NULL){
2989
mc.current_server->prev->next = NULL;
2990
while(mc.current_server != NULL){
2991
server *next = mc.current_server->next;
2993
#pragma GCC diagnostic push
2994
#pragma GCC diagnostic ignored "-Wcast-qual"
2996
free((char *)(mc.current_server->ip));
2998
#pragma GCC diagnostic pop
3000
free(mc.current_server);
3001
mc.current_server = next;
3005
/* Re-raise privileges */
3007
ret_errno = raise_privileges();
3010
perror_plus("Failed to raise privileges");
3013
/* Run network hooks */
3014
run_network_hooks("stop", interfaces_hooks != NULL ?
3015
interfaces_hooks : "", delay);
3017
/* Take down the network interfaces which were brought up */
3019
char *interface = NULL;
3020
while((interface=argz_next(interfaces_to_take_down,
3021
interfaces_to_take_down_size,
3023
ret_errno = take_down_interface(interface);
3026
perror_plus("Failed to take down interface");
3029
if(debug and (interfaces_to_take_down == NULL)){
3030
fprintf_plus(stderr, "No interfaces needed to be taken"
3036
ret_errno = lower_privileges_permanently();
3039
perror_plus("Failed to lower privileges permanently");
3043
free(interfaces_to_take_down);
3044
free(interfaces_hooks);
3046
/* Removes the GPGME temp directory and all files inside */
3047
if(tempdir != NULL){
3048
struct dirent **direntries = NULL;
3049
int tempdir_fd = (int)TEMP_FAILURE_RETRY(open(tempdir, O_RDONLY
3053
if(tempdir_fd == -1){
3054
perror_plus("open");
3057
#if __GLIBC_PREREQ(2, 15)
3058
int numentries = scandirat(tempdir_fd, ".", &direntries,
3059
notdotentries, alphasort);
3060
#else /* not __GLIBC_PREREQ(2, 15) */
3061
int numentries = scandir(tempdir, &direntries, notdotentries,
3063
#endif /* not __GLIBC_PREREQ(2, 15) */
3064
#else /* not __GLIBC__ */
3065
int numentries = scandir(tempdir, &direntries, notdotentries,
3067
#endif /* not __GLIBC__ */
3068
if(numentries >= 0){
3069
for(int i = 0; i < numentries; i++){
3070
ret = unlinkat(tempdir_fd, direntries[i]->d_name, 0);
3072
fprintf_plus(stderr, "unlinkat(open(\"%s\", O_RDONLY),"
3073
" \"%s\", 0): %s\n", tempdir,
3074
direntries[i]->d_name, strerror(errno));
3076
free(direntries[i]);
3079
/* need to clean even if 0 because man page doesn't specify */
3081
if(numentries == -1){
3082
perror_plus("scandir");
3084
ret = rmdir(tempdir);
3085
if(ret == -1 and errno != ENOENT){
3086
perror_plus("rmdir");
3094
sigemptyset(&old_sigterm_action.sa_mask);
3095
old_sigterm_action.sa_handler = SIG_DFL;
3096
ret = (int)TEMP_FAILURE_RETRY(sigaction(signal_received,
3097
&old_sigterm_action,
3100
perror_plus("sigaction");
3103
ret = raise(signal_received);
3104
} while(ret != 0 and errno == EINTR);
3106
perror_plus("raise");
3109
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 ();