108
46
#include <avahi-common/malloc.h>
109
47
#include <avahi-common/error.h>
112
#include <gnutls/gnutls.h> /* All GnuTLS types, constants and
115
init_gnutls_session(),
117
#include <gnutls/openpgp.h>
118
/* gnutls_certificate_set_openpgp_key_file(),
119
GNUTLS_OPENPGP_FMT_BASE64 */
122
#include <gpgme.h> /* All GPGME types, constants and
125
GPGME_PROTOCOL_OpenPGP,
50
#include <sys/types.h> /* socket(), setsockopt(), inet_pton() */
51
#include <sys/socket.h> /* socket(), setsockopt(), struct sockaddr_in6, struct in6_addr, inet_pton() */
52
#include <gnutls/gnutls.h> /* ALL GNUTLS STUFF */
53
#include <gnutls/openpgp.h> /* gnutls with openpgp stuff */
55
#include <unistd.h> /* close() */
56
#include <netinet/in.h>
57
#include <stdbool.h> /* true */
58
#include <string.h> /* memset */
59
#include <arpa/inet.h> /* inet_pton() */
60
#include <iso646.h> /* not */
63
#include <errno.h> /* perror() */
68
#define CERT_ROOT "/conf/conf.d/cryptkeyreq/"
70
#define CERTFILE CERT_ROOT "openpgp-client.txt"
71
#define KEYFILE CERT_ROOT "openpgp-client-key.txt"
128
72
#define BUFFER_SIZE 256
130
#define PATHDIR "/conf/conf.d/mandos"
131
#define SECKEY "seckey.txt"
132
#define PUBKEY "pubkey.txt"
133
#define HOOKDIR "/lib/mandos/network-hooks.d"
136
static const char mandos_protocol_version[] = "1";
137
const char *argp_program_version = "mandos-client " VERSION;
138
const char *argp_program_bug_address = "<mandos@recompile.se>";
139
static const char sys_class_net[] = "/sys/class/net";
140
char *connect_to = NULL;
141
const char *hookdir = HOOKDIR;
145
/* Doubly linked list that need to be circularly linked when used */
146
typedef struct server{
149
AvahiIfIndex if_index;
151
struct timespec last_seen;
156
/* Used for passing in values through the Avahi callback functions */
158
AvahiSimplePoll *simple_poll;
76
gnutls_session_t session;
160
77
gnutls_certificate_credentials_t cred;
161
unsigned int dh_bits;
162
78
gnutls_dh_params_t dh_params;
163
const char *priority;
82
ssize_t gpg_packet_decrypt (char *packet, size_t packet_size, char **new_packet, char *homedir){
83
gpgme_data_t dh_crypto, dh_plain;
165
server *current_server;
168
/* global context so signal handler can reach it*/
169
mandos_context mc = { .simple_poll = NULL, .server = NULL,
170
.dh_bits = 1024, .priority = "SECURE256"
171
":!CTYPE-X.509:+CTYPE-OPENPGP",
172
.current_server = NULL };
174
sig_atomic_t quit_now = 0;
175
int signal_received = 0;
177
/* Function to use when printing errors */
178
void perror_plus(const char *print_text){
180
fprintf(stderr, "Mandos plugin %s: ",
181
program_invocation_short_name);
186
__attribute__((format (gnu_printf, 2, 3)))
187
int fprintf_plus(FILE *stream, const char *format, ...){
189
va_start (ap, format);
191
TEMP_FAILURE_RETRY(fprintf(stream, "Mandos plugin %s: ",
192
program_invocation_short_name));
193
return TEMP_FAILURE_RETRY(vfprintf(stream, format, ap));
197
* Make additional room in "buffer" for at least BUFFER_SIZE more
198
* bytes. "buffer_capacity" is how much is currently allocated,
199
* "buffer_length" is how much is already used.
201
size_t incbuffer(char **buffer, size_t buffer_length,
202
size_t buffer_capacity){
203
if(buffer_length + BUFFER_SIZE > buffer_capacity){
204
*buffer = realloc(*buffer, buffer_capacity + BUFFER_SIZE);
208
buffer_capacity += BUFFER_SIZE;
210
return buffer_capacity;
213
/* Add server to set of servers to retry periodically */
214
bool add_server(const char *ip, uint16_t port, AvahiIfIndex if_index,
217
server *new_server = malloc(sizeof(server));
218
if(new_server == NULL){
219
perror_plus("malloc");
222
*new_server = (server){ .ip = strdup(ip),
224
.if_index = if_index,
226
if(new_server->ip == NULL){
227
perror_plus("strdup");
230
/* Special case of first server */
231
if (mc.current_server == NULL){
232
new_server->next = new_server;
233
new_server->prev = new_server;
234
mc.current_server = new_server;
235
/* Place the new server last in the list */
237
new_server->next = mc.current_server;
238
new_server->prev = mc.current_server->prev;
239
new_server->prev->next = new_server;
240
mc.current_server->prev = new_server;
242
ret = clock_gettime(CLOCK_MONOTONIC, &mc.current_server->last_seen);
244
perror_plus("clock_gettime");
253
static bool init_gpgme(const char *seckey, const char *pubkey,
254
const char *tempdir){
87
size_t new_packet_capacity = 0;
88
size_t new_packet_length = 0;
256
89
gpgme_engine_info_t engine_info;
260
* Helper function to insert pub and seckey to the engine keyring.
262
bool import_key(const char *filename){
265
gpgme_data_t pgp_data;
267
fd = (int)TEMP_FAILURE_RETRY(open(filename, O_RDONLY));
273
rc = gpgme_data_new_from_fd(&pgp_data, fd);
274
if(rc != GPG_ERR_NO_ERROR){
275
fprintf_plus(stderr, "bad gpgme_data_new_from_fd: %s: %s\n",
276
gpgme_strsource(rc), gpgme_strerror(rc));
280
rc = gpgme_op_import(mc.ctx, pgp_data);
281
if(rc != GPG_ERR_NO_ERROR){
282
fprintf_plus(stderr, "bad gpgme_op_import: %s: %s\n",
283
gpgme_strsource(rc), gpgme_strerror(rc));
287
ret = (int)TEMP_FAILURE_RETRY(close(fd));
289
perror_plus("close");
291
gpgme_data_release(pgp_data);
296
fprintf_plus(stderr, "Initializing GPGME\n");
300
92
gpgme_check_version(NULL);
301
rc = gpgme_engine_check_version(GPGME_PROTOCOL_OpenPGP);
302
if(rc != GPG_ERR_NO_ERROR){
303
fprintf_plus(stderr, "bad gpgme_engine_check_version: %s: %s\n",
304
gpgme_strsource(rc), gpgme_strerror(rc));
93
gpgme_engine_check_version(GPGME_PROTOCOL_OpenPGP);
308
/* Set GPGME home directory for the OpenPGP engine only */
309
rc = gpgme_get_engine_info(&engine_info);
310
if(rc != GPG_ERR_NO_ERROR){
311
fprintf_plus(stderr, "bad gpgme_get_engine_info: %s: %s\n",
312
gpgme_strsource(rc), gpgme_strerror(rc));
95
/* Set GPGME home directory */
96
rc = gpgme_get_engine_info (&engine_info);
97
if (rc != GPG_ERR_NO_ERROR){
98
fprintf(stderr, "bad gpgme_get_engine_info: %s: %s\n",
99
gpgme_strsource(rc), gpgme_strerror(rc));
315
102
while(engine_info != NULL){
316
103
if(engine_info->protocol == GPGME_PROTOCOL_OpenPGP){
317
104
gpgme_set_engine_info(GPGME_PROTOCOL_OpenPGP,
318
engine_info->file_name, tempdir);
105
engine_info->file_name, homedir);
321
108
engine_info = engine_info->next;
323
110
if(engine_info == NULL){
324
fprintf_plus(stderr, "Could not set GPGME home dir to %s\n",
329
/* Create new GPGME "context" */
330
rc = gpgme_new(&(mc.ctx));
331
if(rc != GPG_ERR_NO_ERROR){
332
fprintf_plus(stderr, "Mandos plugin mandos-client: "
333
"bad gpgme_new: %s: %s\n", gpgme_strsource(rc),
338
if(not import_key(pubkey) or not import_key(seckey)){
346
* Decrypt OpenPGP data.
347
* Returns -1 on error
349
static ssize_t pgp_packet_decrypt(const char *cryptotext,
352
gpgme_data_t dh_crypto, dh_plain;
355
size_t plaintext_capacity = 0;
356
ssize_t plaintext_length = 0;
359
fprintf_plus(stderr, "Trying to decrypt OpenPGP data\n");
362
/* Create new GPGME data buffer from memory cryptotext */
363
rc = gpgme_data_new_from_mem(&dh_crypto, cryptotext, crypto_size,
365
if(rc != GPG_ERR_NO_ERROR){
366
fprintf_plus(stderr, "bad gpgme_data_new_from_mem: %s: %s\n",
367
gpgme_strsource(rc), gpgme_strerror(rc));
111
fprintf(stderr, "Could not set home dir to %s\n", homedir);
115
/* Create new GPGME data buffer from packet buffer */
116
rc = gpgme_data_new_from_mem(&dh_crypto, packet, packet_size, 0);
117
if (rc != GPG_ERR_NO_ERROR){
118
fprintf(stderr, "bad gpgme_data_new_from_mem: %s: %s\n",
119
gpgme_strsource(rc), gpgme_strerror(rc));
371
123
/* Create new empty GPGME data buffer for the plaintext */
372
124
rc = gpgme_data_new(&dh_plain);
373
if(rc != GPG_ERR_NO_ERROR){
374
fprintf_plus(stderr, "Mandos plugin mandos-client: "
375
"bad gpgme_data_new: %s: %s\n",
376
gpgme_strsource(rc), gpgme_strerror(rc));
377
gpgme_data_release(dh_crypto);
381
/* Decrypt data from the cryptotext data buffer to the plaintext
383
rc = gpgme_op_decrypt(mc.ctx, dh_crypto, dh_plain);
384
if(rc != GPG_ERR_NO_ERROR){
385
fprintf_plus(stderr, "bad gpgme_op_decrypt: %s: %s\n",
386
gpgme_strsource(rc), gpgme_strerror(rc));
387
plaintext_length = -1;
389
gpgme_decrypt_result_t result;
390
result = gpgme_op_decrypt_result(mc.ctx);
392
fprintf_plus(stderr, "gpgme_op_decrypt_result failed\n");
394
fprintf_plus(stderr, "Unsupported algorithm: %s\n",
395
result->unsupported_algorithm);
396
fprintf_plus(stderr, "Wrong key usage: %u\n",
397
result->wrong_key_usage);
398
if(result->file_name != NULL){
399
fprintf_plus(stderr, "File name: %s\n", result->file_name);
401
gpgme_recipient_t recipient;
402
recipient = result->recipients;
403
while(recipient != NULL){
404
fprintf_plus(stderr, "Public key algorithm: %s\n",
405
gpgme_pubkey_algo_name
406
(recipient->pubkey_algo));
407
fprintf_plus(stderr, "Key ID: %s\n", recipient->keyid);
408
fprintf_plus(stderr, "Secret key available: %s\n",
409
recipient->status == GPG_ERR_NO_SECKEY
411
recipient = recipient->next;
419
fprintf_plus(stderr, "Decryption of OpenPGP data succeeded\n");
125
if (rc != GPG_ERR_NO_ERROR){
126
fprintf(stderr, "bad gpgme_data_new: %s: %s\n",
127
gpgme_strsource(rc), gpgme_strerror(rc));
131
/* Create new GPGME "context" */
132
rc = gpgme_new(&ctx);
133
if (rc != GPG_ERR_NO_ERROR){
134
fprintf(stderr, "bad gpgme_new: %s: %s\n",
135
gpgme_strsource(rc), gpgme_strerror(rc));
139
/* Decrypt data from the FILE pointer to the plaintext data buffer */
140
rc = gpgme_op_decrypt(ctx, dh_crypto, dh_plain);
141
if (rc != GPG_ERR_NO_ERROR){
142
fprintf(stderr, "bad gpgme_op_decrypt: %s: %s\n",
143
gpgme_strsource(rc), gpgme_strerror(rc));
147
/* gpgme_decrypt_result_t result; */
148
/* result = gpgme_op_decrypt_result(ctx); */
149
/* fprintf(stderr, "Unsupported algorithm: %s\n", result->unsupported_algorithm); */
150
/* fprintf(stderr, "Wrong key usage: %d\n", result->wrong_key_usage); */
151
/* if(result->file_name != NULL){ */
152
/* fprintf(stderr, "File name: %s\n", result->file_name); */
154
/* gpgme_recipient_t recipient; */
155
/* recipient = result->recipients; */
157
/* while(recipient != NULL){ */
158
/* fprintf(stderr, "Public key algorithm: %s\n", */
159
/* gpgme_pubkey_algo_name(recipient->pubkey_algo)); */
160
/* fprintf(stderr, "Key ID: %s\n", recipient->keyid); */
161
/* fprintf(stderr, "Secret key available: %s\n", */
162
/* recipient->status == GPG_ERR_NO_SECKEY ? "No" : "Yes"); */
163
/* recipient = recipient->next; */
167
/* Delete the GPGME FILE pointer cryptotext data buffer */
168
gpgme_data_release(dh_crypto);
422
170
/* Seek back to the beginning of the GPGME plaintext data buffer */
423
if(gpgme_data_seek(dh_plain, (off_t)0, SEEK_SET) == -1){
424
perror_plus("gpgme_data_seek");
425
plaintext_length = -1;
171
gpgme_data_seek(dh_plain, 0, SEEK_SET);
431
plaintext_capacity = incbuffer(plaintext,
432
(size_t)plaintext_length,
434
if(plaintext_capacity == 0){
435
perror_plus("incbuffer");
436
plaintext_length = -1;
175
if (new_packet_length + BUFFER_SIZE > new_packet_capacity){
176
*new_packet = realloc(*new_packet, new_packet_capacity + BUFFER_SIZE);
177
if (*new_packet == NULL){
181
new_packet_capacity += BUFFER_SIZE;
440
ret = gpgme_data_read(dh_plain, *plaintext + plaintext_length,
184
ret = gpgme_data_read(dh_plain, *new_packet + new_packet_length, BUFFER_SIZE);
442
185
/* Print the data, if any */
187
/* If password is empty, then a incorrect error will be printed */
448
perror_plus("gpgme_data_read");
449
plaintext_length = -1;
452
plaintext_length += ret;
456
fprintf_plus(stderr, "Decrypted password is: ");
457
for(ssize_t i = 0; i < plaintext_length; i++){
458
fprintf(stderr, "%02hhX ", (*plaintext)[i]);
460
fprintf(stderr, "\n");
465
/* Delete the GPGME cryptotext data buffer */
466
gpgme_data_release(dh_crypto);
468
/* Delete the GPGME plaintext data buffer */
191
perror("gpgme_data_read");
194
new_packet_length += ret;
197
/* Delete the GPGME plaintext data buffer */
469
198
gpgme_data_release(dh_plain);
470
return plaintext_length;
199
return new_packet_length;
473
static const char * safer_gnutls_strerror(int value){
474
const char *ret = gnutls_strerror(value); /* Spurious warning from
475
-Wunreachable-code */
202
static const char * safer_gnutls_strerror (int value) {
203
const char *ret = gnutls_strerror (value);
477
205
ret = "(unknown)";
481
/* GnuTLS log function callback */
482
static void debuggnutls(__attribute__((unused)) int level,
484
fprintf_plus(stderr, "GnuTLS: %s", string);
209
void debuggnutls(int level, const char* string){
210
fprintf(stderr, "%s", string);
487
static int init_gnutls_global(const char *pubkeyfilename,
488
const char *seckeyfilename){
213
int initgnutls(encrypted_session *es){
492
fprintf_plus(stderr, "Initializing GnuTLS\n");
495
ret = gnutls_global_init();
496
if(ret != GNUTLS_E_SUCCESS){
497
fprintf_plus(stderr, "GnuTLS global_init: %s\n",
498
safer_gnutls_strerror(ret));
503
/* "Use a log level over 10 to enable all debugging options."
506
gnutls_global_set_log_level(11);
507
gnutls_global_set_log_function(debuggnutls);
510
/* OpenPGP credentials */
511
ret = gnutls_certificate_allocate_credentials(&mc.cred);
512
if(ret != GNUTLS_E_SUCCESS){
513
fprintf_plus(stderr, "GnuTLS memory error: %s\n",
514
safer_gnutls_strerror(ret));
515
gnutls_global_deinit();
520
fprintf_plus(stderr, "Attempting to use OpenPGP public key %s and"
521
" secret key %s as GnuTLS credentials\n",
217
if ((ret = gnutls_global_init ())
218
!= GNUTLS_E_SUCCESS) {
219
fprintf (stderr, "global_init: %s\n", safer_gnutls_strerror(ret));
223
/* Uncomment to enable full debuggin on the gnutls library */
224
/* gnutls_global_set_log_level(11); */
225
/* gnutls_global_set_log_function(debuggnutls); */
228
/* openpgp credentials */
229
if ((ret = gnutls_certificate_allocate_credentials (&es->cred))
230
!= GNUTLS_E_SUCCESS) {
231
fprintf (stderr, "memory error: %s\n", safer_gnutls_strerror(ret));
526
235
ret = gnutls_certificate_set_openpgp_key_file
527
(mc.cred, pubkeyfilename, seckeyfilename,
528
GNUTLS_OPENPGP_FMT_BASE64);
529
if(ret != GNUTLS_E_SUCCESS){
531
"Error[%d] while reading the OpenPGP key pair ('%s',"
532
" '%s')\n", ret, pubkeyfilename, seckeyfilename);
533
fprintf_plus(stderr, "The GnuTLS error is: %s\n",
534
safer_gnutls_strerror(ret));
538
/* GnuTLS server initialization */
539
ret = gnutls_dh_params_init(&mc.dh_params);
540
if(ret != GNUTLS_E_SUCCESS){
541
fprintf_plus(stderr, "Error in GnuTLS DH parameter"
542
" initialization: %s\n",
543
safer_gnutls_strerror(ret));
546
ret = gnutls_dh_params_generate2(mc.dh_params, mc.dh_bits);
547
if(ret != GNUTLS_E_SUCCESS){
548
fprintf_plus(stderr, "Error in GnuTLS prime generation: %s\n",
549
safer_gnutls_strerror(ret));
553
gnutls_certificate_set_dh_params(mc.cred, mc.dh_params);
559
gnutls_certificate_free_credentials(mc.cred);
560
gnutls_global_deinit();
561
gnutls_dh_params_deinit(mc.dh_params);
565
static int init_gnutls_session(gnutls_session_t *session){
567
/* GnuTLS session creation */
569
ret = gnutls_init(session, GNUTLS_SERVER);
573
} while(ret == GNUTLS_E_INTERRUPTED or ret == GNUTLS_E_AGAIN);
574
if(ret != GNUTLS_E_SUCCESS){
576
"Error in GnuTLS session initialization: %s\n",
577
safer_gnutls_strerror(ret));
583
ret = gnutls_priority_set_direct(*session, mc.priority, &err);
585
gnutls_deinit(*session);
588
} while(ret == GNUTLS_E_INTERRUPTED or ret == GNUTLS_E_AGAIN);
589
if(ret != GNUTLS_E_SUCCESS){
590
fprintf_plus(stderr, "Syntax error at: %s\n", err);
591
fprintf_plus(stderr, "GnuTLS error: %s\n",
592
safer_gnutls_strerror(ret));
593
gnutls_deinit(*session);
599
ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,
602
gnutls_deinit(*session);
605
} while(ret == GNUTLS_E_INTERRUPTED or ret == GNUTLS_E_AGAIN);
606
if(ret != GNUTLS_E_SUCCESS){
607
fprintf_plus(stderr, "Error setting GnuTLS credentials: %s\n",
608
safer_gnutls_strerror(ret));
609
gnutls_deinit(*session);
236
(es->cred, CERTFILE, KEYFILE, GNUTLS_OPENPGP_FMT_BASE64);
237
if (ret != GNUTLS_E_SUCCESS) {
239
(stderr, "Error[%d] while reading the OpenPGP key pair ('%s', '%s')\n",
240
ret, CERTFILE, KEYFILE);
241
fprintf(stdout, "The Error is: %s\n",
242
safer_gnutls_strerror(ret));
246
//Gnutls server initialization
247
if ((ret = gnutls_dh_params_init (&es->dh_params))
248
!= GNUTLS_E_SUCCESS) {
249
fprintf (stderr, "Error in dh parameter initialization: %s\n",
250
safer_gnutls_strerror(ret));
254
if ((ret = gnutls_dh_params_generate2 (es->dh_params, DH_BITS))
255
!= GNUTLS_E_SUCCESS) {
256
fprintf (stderr, "Error in prime generation: %s\n",
257
safer_gnutls_strerror(ret));
261
gnutls_certificate_set_dh_params (es->cred, es->dh_params);
263
// Gnutls session creation
264
if ((ret = gnutls_init (&es->session, GNUTLS_SERVER))
265
!= GNUTLS_E_SUCCESS){
266
fprintf(stderr, "Error in gnutls session initialization: %s\n",
267
safer_gnutls_strerror(ret));
270
if ((ret = gnutls_priority_set_direct (es->session, "NORMAL", &err))
271
!= GNUTLS_E_SUCCESS) {
272
fprintf(stderr, "Syntax error at: %s\n", err);
273
fprintf(stderr, "Gnutls error: %s\n",
274
safer_gnutls_strerror(ret));
278
if ((ret = gnutls_credentials_set
279
(es->session, GNUTLS_CRD_CERTIFICATE, es->cred))
280
!= GNUTLS_E_SUCCESS) {
281
fprintf(stderr, "Error setting a credentials set: %s\n",
282
safer_gnutls_strerror(ret));
613
286
/* ignore client certificate if any. */
614
gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);
287
gnutls_certificate_server_set_request (es->session, GNUTLS_CERT_IGNORE);
616
gnutls_dh_set_prime_bits(*session, mc.dh_bits);
289
gnutls_dh_set_prime_bits (es->session, DH_BITS);
621
/* Avahi log function callback */
622
static void empty_log(__attribute__((unused)) AvahiLogLevel level,
623
__attribute__((unused)) const char *txt){}
294
void empty_log(AvahiLogLevel level, const char *txt){}
625
/* Called when a Mandos server is found */
626
static int start_mandos_communication(const char *ip, uint16_t port,
627
AvahiIfIndex if_index,
629
int ret, tcp_sd = -1;
632
struct sockaddr_in in;
633
struct sockaddr_in6 in6;
296
int start_mandos_communcation(char *ip, uint16_t port){
298
struct sockaddr_in6 to;
299
struct in6_addr ip_addr;
300
encrypted_session es;
635
301
char *buffer = NULL;
636
char *decrypted_buffer = NULL;
302
char *decrypted_buffer;
637
303
size_t buffer_length = 0;
638
304
size_t buffer_capacity = 0;
641
gnutls_session_t session;
642
int pf; /* Protocol family */
659
fprintf_plus(stderr, "Bad address family: %d\n", af);
664
ret = init_gnutls_session(&session);
670
fprintf_plus(stderr, "Setting up a TCP connection to %s, port %"
671
PRIu16 "\n", ip, port);
674
tcp_sd = socket(pf, SOCK_STREAM, 0);
677
perror_plus("socket");
687
memset(&to, 0, sizeof(to));
689
to.in6.sin6_family = (sa_family_t)af;
690
ret = inet_pton(af, ip, &to.in6.sin6_addr);
692
to.in.sin_family = (sa_family_t)af;
693
ret = inet_pton(af, ip, &to.in.sin_addr);
697
perror_plus("inet_pton");
305
ssize_t decrypted_buffer_size;
309
tcp_sd = socket(PF_INET6, SOCK_STREAM, 0);
315
ret = setsockopt(tcp_sd, SOL_SOCKET, SO_BINDTODEVICE, "eth0", 5);
317
perror("setsockopt bindtodevice");
321
memset(&to,0,sizeof(to));
322
to.sin6_family = AF_INET6;
323
ret = inet_pton(AF_INET6, ip, &ip_addr);
703
fprintf_plus(stderr, "Bad address: %s\n", ip);
708
to.in6.sin6_port = htons(port); /* Spurious warnings from
710
-Wunreachable-code */
712
if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */
713
(&to.in6.sin6_addr)){ /* -Wstrict-aliasing=2 or lower and
715
if(if_index == AVAHI_IF_UNSPEC){
716
fprintf_plus(stderr, "An IPv6 link-local address is"
717
" incomplete without a network interface\n");
721
/* Set the network interface number as scope */
722
to.in6.sin6_scope_id = (uint32_t)if_index;
725
to.in.sin_port = htons(port); /* Spurious warnings from
727
-Wunreachable-code */
736
if(af == AF_INET6 and if_index != AVAHI_IF_UNSPEC){
737
char interface[IF_NAMESIZE];
738
if(if_indextoname((unsigned int)if_index, interface) == NULL){
739
perror_plus("if_indextoname");
741
fprintf_plus(stderr, "Connection to: %s%%%s, port %" PRIu16
742
"\n", ip, interface, port);
745
fprintf_plus(stderr, "Connection to: %s, port %" PRIu16 "\n",
748
char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?
749
INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";
752
pcret = inet_ntop(af, &(to.in6.sin6_addr), addrstr,
755
pcret = inet_ntop(af, &(to.in.sin_addr), addrstr,
759
perror_plus("inet_ntop");
761
if(strcmp(addrstr, ip) != 0){
762
fprintf_plus(stderr, "Canonical address form: %s\n", addrstr);
773
ret = connect(tcp_sd, &to.in6, sizeof(to));
775
ret = connect(tcp_sd, &to.in, sizeof(to)); /* IPv4 */
778
if ((errno != ECONNREFUSED and errno != ENETUNREACH) or debug){
780
perror_plus("connect");
791
const char *out = mandos_protocol_version;
794
size_t out_size = strlen(out);
795
ret = (int)TEMP_FAILURE_RETRY(write(tcp_sd, out + written,
796
out_size - written));
799
perror_plus("write");
803
written += (size_t)ret;
804
if(written < out_size){
807
if(out == mandos_protocol_version){
822
fprintf_plus(stderr, "Establishing TLS session with %s\n", ip);
830
/* This casting via intptr_t is to eliminate warning about casting
831
an int to a pointer type. This is exactly how the GnuTLS Guile
832
function "set-session-transport-fd!" does it. */
833
gnutls_transport_set_ptr(session,
834
(gnutls_transport_ptr_t)(intptr_t)tcp_sd);
842
ret = gnutls_handshake(session);
847
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
849
if(ret != GNUTLS_E_SUCCESS){
851
fprintf_plus(stderr, "*** GnuTLS Handshake failed ***\n");
858
/* Read OpenPGP packet that contains the wanted password */
861
fprintf_plus(stderr, "Retrieving OpenPGP encrypted password from"
872
buffer_capacity = incbuffer(&buffer, buffer_length,
874
if(buffer_capacity == 0){
876
perror_plus("incbuffer");
886
sret = gnutls_record_recv(session, buffer+buffer_length,
329
fprintf(stderr, "Bad address: %s\n", ip);
332
to.sin6_port = htons(port);
333
to.sin6_scope_id = if_nametoindex("eth0");
335
ret = connect(tcp_sd, (struct sockaddr *) &to, sizeof(to));
341
ret = initgnutls (&es);
348
gnutls_transport_set_ptr (es.session, (gnutls_transport_ptr_t) tcp_sd);
350
ret = gnutls_handshake (es.session);
352
if (ret != GNUTLS_E_SUCCESS){
353
fprintf(stderr, "\n*** Handshake failed ***\n");
361
if (buffer_length + BUFFER_SIZE > buffer_capacity){
362
buffer = realloc(buffer, buffer_capacity + BUFFER_SIZE);
367
buffer_capacity += BUFFER_SIZE;
370
ret = gnutls_record_recv
371
(es.session, buffer+buffer_length, BUFFER_SIZE);
893
377
case GNUTLS_E_INTERRUPTED:
894
378
case GNUTLS_E_AGAIN:
896
380
case GNUTLS_E_REHANDSHAKE:
898
ret = gnutls_handshake(session);
904
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
906
fprintf_plus(stderr, "*** GnuTLS Re-handshake failed "
381
ret = gnutls_handshake (es.session);
383
fprintf(stderr, "\n*** Handshake failed ***\n");
914
fprintf_plus(stderr, "Unknown error while reading data from"
915
" encrypted session with Mandos server\n");
916
gnutls_bye(session, GNUTLS_SHUT_RDWR);
390
fprintf(stderr, "Unknown error while reading data from encrypted session with mandos server\n");
392
gnutls_bye (es.session, GNUTLS_SHUT_RDWR);
921
buffer_length += (size_t) sret;
926
fprintf_plus(stderr, "Closing TLS session\n");
935
ret = gnutls_bye(session, GNUTLS_SHUT_RDWR);
940
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
942
if(buffer_length > 0){
943
ssize_t decrypted_buffer_size;
944
decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,
946
if(decrypted_buffer_size >= 0){
949
while(written < (size_t) decrypted_buffer_size){
955
ret = (int)fwrite(decrypted_buffer + written, 1,
956
(size_t)decrypted_buffer_size - written,
958
if(ret == 0 and ferror(stdout)){
961
fprintf_plus(stderr, "Error writing encrypted data: %s\n",
967
written += (size_t)ret;
973
/* Shutdown procedure */
978
free(decrypted_buffer);
981
ret = (int)TEMP_FAILURE_RETRY(close(tcp_sd));
987
perror_plus("close");
989
gnutls_deinit(session);
396
buffer_length += ret;
400
if (buffer_length > 0){
401
if ((decrypted_buffer_size = gpg_packet_decrypt(buffer, buffer_length, &decrypted_buffer, CERT_ROOT)) == 0){
404
fwrite (decrypted_buffer, 1, decrypted_buffer_size, stdout);
405
free(decrypted_buffer);
412
gnutls_bye (es.session, GNUTLS_SHUT_RDWR);
415
gnutls_deinit (es.session);
416
gnutls_certificate_free_credentials (es.cred);
417
gnutls_global_deinit ();
999
static void resolve_callback(AvahiSServiceResolver *r,
1000
AvahiIfIndex interface,
1001
AvahiProtocol proto,
1002
AvahiResolverEvent event,
1006
const char *host_name,
1007
const AvahiAddress *address,
1009
AVAHI_GCC_UNUSED AvahiStringList *txt,
1010
AVAHI_GCC_UNUSED AvahiLookupResultFlags
1012
AVAHI_GCC_UNUSED void* userdata){
1015
/* Called whenever a service has been resolved successfully or
1024
case AVAHI_RESOLVER_FAILURE:
1025
fprintf_plus(stderr, "(Avahi Resolver) Failed to resolve service "
1026
"'%s' of type '%s' in domain '%s': %s\n", name, type,
1028
avahi_strerror(avahi_server_errno(mc.server)));
1031
case AVAHI_RESOLVER_FOUND:
1033
char ip[AVAHI_ADDRESS_STR_MAX];
1034
avahi_address_snprint(ip, sizeof(ip), address);
1036
fprintf_plus(stderr, "Mandos server \"%s\" found on %s (%s, %"
1037
PRIdMAX ") on port %" PRIu16 "\n", name,
1038
host_name, ip, (intmax_t)interface, port);
1040
int ret = start_mandos_communication(ip, port, interface,
1041
avahi_proto_to_af(proto));
1043
avahi_simple_poll_quit(mc.simple_poll);
1045
if(not add_server(ip, port, interface,
1046
avahi_proto_to_af(proto))){
1047
fprintf_plus(stderr, "Failed to add server \"%s\" to server"
1053
avahi_s_service_resolver_free(r);
1056
static void browse_callback(AvahiSServiceBrowser *b,
1057
AvahiIfIndex interface,
1058
AvahiProtocol protocol,
1059
AvahiBrowserEvent event,
1063
AVAHI_GCC_UNUSED AvahiLookupResultFlags
1065
AVAHI_GCC_UNUSED void* userdata){
1068
/* Called whenever a new services becomes available on the LAN or
1069
is removed from the LAN */
1077
case AVAHI_BROWSER_FAILURE:
1079
fprintf_plus(stderr, "(Avahi browser) %s\n",
1080
avahi_strerror(avahi_server_errno(mc.server)));
1081
avahi_simple_poll_quit(mc.simple_poll);
1084
case AVAHI_BROWSER_NEW:
1085
/* We ignore the returned Avahi resolver object. In the callback
1086
function we free it. If the Avahi server is terminated before
1087
the callback function is called the Avahi server will free the
1090
if(avahi_s_service_resolver_new(mc.server, interface, protocol,
1091
name, type, domain, protocol, 0,
1092
resolve_callback, NULL) == NULL)
1093
fprintf_plus(stderr, "Avahi: Failed to resolve service '%s':"
1095
avahi_strerror(avahi_server_errno(mc.server)));
1098
case AVAHI_BROWSER_REMOVE:
1101
case AVAHI_BROWSER_ALL_FOR_NOW:
1102
case AVAHI_BROWSER_CACHE_EXHAUSTED:
1104
fprintf_plus(stderr, "No Mandos server found, still"
1111
/* Signal handler that stops main loop after SIGTERM */
1112
static void handle_sigterm(int sig){
1117
signal_received = sig;
1118
int old_errno = errno;
1119
/* set main loop to exit */
1120
if(mc.simple_poll != NULL){
1121
avahi_simple_poll_quit(mc.simple_poll);
1126
bool get_flags(const char *ifname, struct ifreq *ifr){
1130
int s = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1133
perror_plus("socket");
1137
strcpy(ifr->ifr_name, ifname);
1138
ret = ioctl(s, SIOCGIFFLAGS, ifr);
1142
perror_plus("ioctl SIOCGIFFLAGS");
1150
bool good_flags(const char *ifname, const struct ifreq *ifr){
1152
/* Reject the loopback device */
1153
if(ifr->ifr_flags & IFF_LOOPBACK){
1155
fprintf_plus(stderr, "Rejecting loopback interface \"%s\"\n",
1160
/* Accept point-to-point devices only if connect_to is specified */
1161
if(connect_to != NULL and (ifr->ifr_flags & IFF_POINTOPOINT)){
1163
fprintf_plus(stderr, "Accepting point-to-point interface"
1164
" \"%s\"\n", ifname);
1168
/* Otherwise, reject non-broadcast-capable devices */
1169
if(not (ifr->ifr_flags & IFF_BROADCAST)){
1171
fprintf_plus(stderr, "Rejecting non-broadcast interface"
1172
" \"%s\"\n", ifname);
1176
/* Reject non-ARP interfaces (including dummy interfaces) */
1177
if(ifr->ifr_flags & IFF_NOARP){
1179
fprintf_plus(stderr, "Rejecting non-ARP interface \"%s\"\n",
1185
/* Accept this device */
1187
fprintf_plus(stderr, "Interface \"%s\" is good\n", ifname);
1193
* This function determines if a directory entry in /sys/class/net
1194
* corresponds to an acceptable network device.
1195
* (This function is passed to scandir(3) as a filter function.)
1197
int good_interface(const struct dirent *if_entry){
1198
if(if_entry->d_name[0] == '.'){
1203
if(not get_flags(if_entry->d_name, &ifr)){
1205
fprintf_plus(stderr, "Failed to get flags for interface "
1206
"\"%s\"\n", if_entry->d_name);
1211
if(not good_flags(if_entry->d_name, &ifr)){
1218
* This function determines if a network interface is up.
1220
bool interface_is_up(const char *interface){
1222
if(not get_flags(interface, &ifr)){
1224
fprintf_plus(stderr, "Failed to get flags for interface "
1225
"\"%s\"\n", interface);
1230
return (bool)(ifr.ifr_flags & IFF_UP);
1234
* This function determines if a network interface is running
1236
bool interface_is_running(const char *interface){
1238
if(not get_flags(interface, &ifr)){
1240
fprintf_plus(stderr, "Failed to get flags for interface "
1241
"\"%s\"\n", interface);
1246
return (bool)(ifr.ifr_flags & IFF_RUNNING);
1249
int notdotentries(const struct dirent *direntry){
1250
/* Skip "." and ".." */
1251
if(direntry->d_name[0] == '.'
1252
and (direntry->d_name[1] == '\0'
1253
or (direntry->d_name[1] == '.'
1254
and direntry->d_name[2] == '\0'))){
1260
/* Is this directory entry a runnable program? */
1261
int runnable_hook(const struct dirent *direntry){
1266
if((direntry->d_name)[0] == '\0'){
1271
sret = strspn(direntry->d_name, "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
1272
"abcdefghijklmnopqrstuvwxyz"
1275
if((direntry->d_name)[sret] != '\0'){
1276
/* Contains non-allowed characters */
1278
fprintf_plus(stderr, "Ignoring hook \"%s\" with bad name\n",
1284
char *fullname = NULL;
1285
ret = asprintf(&fullname, "%s/%s", hookdir, direntry->d_name);
1287
perror_plus("asprintf");
1291
ret = stat(fullname, &st);
1294
perror_plus("Could not stat hook");
1298
if(not (S_ISREG(st.st_mode))){
1299
/* Not a regular file */
1301
fprintf_plus(stderr, "Ignoring hook \"%s\" - not a file\n",
1306
if(not (st.st_mode & (S_IXUSR | S_IXGRP | S_IXOTH))){
1307
/* Not executable */
1309
fprintf_plus(stderr, "Ignoring hook \"%s\" - not executable\n",
1315
fprintf_plus(stderr, "Hook \"%s\" is acceptable\n",
1321
int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval){
1323
struct timespec now;
1324
struct timespec waited_time;
1325
intmax_t block_time;
1328
if(mc.current_server == NULL){
1330
fprintf_plus(stderr, "Wait until first server is found."
1333
ret = avahi_simple_poll_iterate(s, -1);
1336
fprintf_plus(stderr, "Check current_server if we should run"
1339
/* the current time */
1340
ret = clock_gettime(CLOCK_MONOTONIC, &now);
1342
perror_plus("clock_gettime");
1345
/* Calculating in ms how long time between now and server
1346
who we visted longest time ago. Now - last seen. */
1347
waited_time.tv_sec = (now.tv_sec
1348
- mc.current_server->last_seen.tv_sec);
1349
waited_time.tv_nsec = (now.tv_nsec
1350
- mc.current_server->last_seen.tv_nsec);
1351
/* total time is 10s/10,000ms.
1352
Converting to s from ms by dividing by 1,000,
1353
and ns to ms by dividing by 1,000,000. */
1354
block_time = ((retry_interval
1355
- ((intmax_t)waited_time.tv_sec * 1000))
1356
- ((intmax_t)waited_time.tv_nsec / 1000000));
1359
fprintf_plus(stderr, "Blocking for %" PRIdMAX " ms\n",
1363
if(block_time <= 0){
1364
ret = start_mandos_communication(mc.current_server->ip,
1365
mc.current_server->port,
1366
mc.current_server->if_index,
1367
mc.current_server->af);
1369
avahi_simple_poll_quit(mc.simple_poll);
1372
ret = clock_gettime(CLOCK_MONOTONIC,
1373
&mc.current_server->last_seen);
1375
perror_plus("clock_gettime");
1378
mc.current_server = mc.current_server->next;
1379
block_time = 0; /* Call avahi to find new Mandos
1380
servers, but don't block */
1383
ret = avahi_simple_poll_iterate(s, (int)block_time);
1386
if (ret > 0 or errno != EINTR){
1387
return (ret != 1) ? ret : 0;
1393
/* Set effective uid to 0, return errno */
1394
error_t raise_privileges(void){
1395
error_t old_errno = errno;
1396
error_t ret_errno = 0;
1397
if(seteuid(0) == -1){
1399
perror_plus("seteuid");
1405
/* Set effective and real user ID to 0. Return errno. */
1406
error_t raise_privileges_permanently(void){
1407
error_t old_errno = errno;
1408
error_t ret_errno = raise_privileges();
1413
if(setuid(0) == -1){
1415
perror_plus("seteuid");
1421
/* Set effective user ID to unprivileged saved user ID */
1422
error_t lower_privileges(void){
1423
error_t old_errno = errno;
1424
error_t ret_errno = 0;
1425
if(seteuid(uid) == -1){
1427
perror_plus("seteuid");
1433
/* Lower privileges permanently */
1434
error_t lower_privileges_permanently(void){
1435
error_t old_errno = errno;
1436
error_t ret_errno = 0;
1437
if(setuid(uid) == -1){
1439
perror_plus("setuid");
1445
bool run_network_hooks(const char *mode, const char *interface,
1447
struct dirent **direntries;
1448
struct dirent *direntry;
1450
int numhooks = scandir(hookdir, &direntries, runnable_hook,
1453
perror_plus("scandir");
1455
int devnull = open("/dev/null", O_RDONLY);
1456
for(int i = 0; i < numhooks; i++){
1457
direntry = direntries[i];
1458
char *fullname = NULL;
1459
ret = asprintf(&fullname, "%s/%s", hookdir, direntry->d_name);
1461
perror_plus("asprintf");
1465
fprintf_plus(stderr, "Running network hook \"%s\"\n",
1468
pid_t hook_pid = fork();
1471
/* Raise privileges */
1472
raise_privileges_permanently();
1477
perror_plus("setgid");
1479
/* Reset supplementary groups */
1481
ret = setgroups(0, NULL);
1483
perror_plus("setgroups");
1485
dup2(devnull, STDIN_FILENO);
1487
dup2(STDERR_FILENO, STDOUT_FILENO);
1488
ret = setenv("MANDOSNETHOOKDIR", hookdir, 1);
1490
perror_plus("setenv");
1493
ret = setenv("DEVICE", interface, 1);
1495
perror_plus("setenv");
1498
ret = setenv("VERBOSITY", debug ? "1" : "0", 1);
1500
perror_plus("setenv");
1503
ret = setenv("MODE", mode, 1);
1505
perror_plus("setenv");
1509
ret = asprintf(&delaystring, "%f", delay);
1511
perror_plus("asprintf");
1514
ret = setenv("DELAY", delaystring, 1);
1517
perror_plus("setenv");
1521
if(connect_to != NULL){
1522
ret = setenv("CONNECT", connect_to, 1);
1524
perror_plus("setenv");
1528
if(execl(fullname, direntry->d_name, mode, NULL) == -1){
1529
perror_plus("execl");
1530
_exit(EXIT_FAILURE);
1534
if(TEMP_FAILURE_RETRY(waitpid(hook_pid, &status, 0)) == -1){
1535
perror_plus("waitpid");
1539
if(WIFEXITED(status)){
1540
if(WEXITSTATUS(status) != 0){
1541
fprintf_plus(stderr, "Warning: network hook \"%s\" exited"
1542
" with status %d\n", direntry->d_name,
1543
WEXITSTATUS(status));
1547
} else if(WIFSIGNALED(status)){
1548
fprintf_plus(stderr, "Warning: network hook \"%s\" died by"
1549
" signal %d\n", direntry->d_name,
1554
fprintf_plus(stderr, "Warning: network hook \"%s\""
1555
" crashed\n", direntry->d_name);
1562
fprintf_plus(stderr, "Network hook \"%s\" ran successfully\n",
1571
error_t bring_up_interface(const char *const interface,
1574
error_t old_errno = errno;
1575
error_t ret_errno = 0;
1576
int ret, ret_setflags;
1577
struct ifreq network;
1578
unsigned int if_index = if_nametoindex(interface);
1580
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
1590
if(not interface_is_up(interface)){
1591
if(not get_flags(interface, &network) and debug){
1593
fprintf_plus(stderr, "Failed to get flags for interface "
1594
"\"%s\"\n", interface);
1597
network.ifr_flags |= IFF_UP;
1599
sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1602
perror_plus("socket");
1614
fprintf_plus(stderr, "Bringing up interface \"%s\"\n",
1618
/* Raise priviliges */
1622
/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO
1623
messages about the network interface to mess up the prompt */
1624
int ret_linux = klogctl(8, NULL, 5);
1625
bool restore_loglevel = true;
1626
if(ret_linux == -1){
1627
restore_loglevel = false;
1628
perror_plus("klogctl");
1630
#endif /* __linux__ */
1631
ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
1634
if(restore_loglevel){
1635
ret_linux = klogctl(7, NULL, 0);
1636
if(ret_linux == -1){
1637
perror_plus("klogctl");
1640
#endif /* __linux__ */
1642
/* Lower privileges */
1645
/* Close the socket */
1646
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1648
perror_plus("close");
1651
if(ret_setflags == -1){
1653
perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");
1658
fprintf_plus(stderr, "Interface \"%s\" is already up; good\n",
1662
/* Sleep checking until interface is running.
1663
Check every 0.25s, up to total time of delay */
1664
for(int i=0; i < delay * 4; i++){
1665
if(interface_is_running(interface)){
1668
struct timespec sleeptime = { .tv_nsec = 250000000 };
1669
ret = nanosleep(&sleeptime, NULL);
1670
if(ret == -1 and errno != EINTR){
1671
perror_plus("nanosleep");
1679
error_t take_down_interface(const char *const interface){
1681
error_t old_errno = errno;
1682
error_t ret_errno = 0;
1683
int ret, ret_setflags;
1684
struct ifreq network;
1685
unsigned int if_index = if_nametoindex(interface);
1687
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
1691
if(interface_is_up(interface)){
1692
if(not get_flags(interface, &network) and debug){
1694
fprintf_plus(stderr, "Failed to get flags for interface "
1695
"\"%s\"\n", interface);
1698
network.ifr_flags &= ~(short)IFF_UP; /* clear flag */
1700
sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1703
perror_plus("socket");
1709
fprintf_plus(stderr, "Taking down interface \"%s\"\n",
1713
/* Raise priviliges */
1716
ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
1719
/* Lower privileges */
1722
/* Close the socket */
1723
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1725
perror_plus("close");
1728
if(ret_setflags == -1){
1730
perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");
1735
fprintf_plus(stderr, "Interface \"%s\" is already down; odd\n",
1743
int main(int argc, char *argv[]){
1744
AvahiSServiceBrowser *sb = NULL;
1749
int exitcode = EXIT_SUCCESS;
1750
char *interfaces = NULL;
1751
size_t interfaces_size = 0;
1752
char *interfaces_to_take_down = NULL;
1753
size_t interfaces_to_take_down_size = 0;
1754
char tempdir[] = "/tmp/mandosXXXXXX";
1755
bool tempdir_created = false;
1756
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
1757
const char *seckey = PATHDIR "/" SECKEY;
1758
const char *pubkey = PATHDIR "/" PUBKEY;
1759
char *interfaces_hooks = NULL;
1760
size_t interfaces_hooks_size = 0;
1762
bool gnutls_initialized = false;
1763
bool gpgme_initialized = false;
1765
double retry_interval = 10; /* 10s between trying a server and
1766
retrying the same server again */
1768
struct sigaction old_sigterm_action = { .sa_handler = SIG_DFL };
1769
struct sigaction sigterm_action = { .sa_handler = handle_sigterm };
1774
/* Lower any group privileges we might have, just to be safe */
1778
perror_plus("setgid");
1781
/* Lower user privileges (temporarily) */
1785
perror_plus("seteuid");
1793
struct argp_option options[] = {
1794
{ .name = "debug", .key = 128,
1795
.doc = "Debug mode", .group = 3 },
1796
{ .name = "connect", .key = 'c',
1797
.arg = "ADDRESS:PORT",
1798
.doc = "Connect directly to a specific Mandos server",
1800
{ .name = "interface", .key = 'i',
1802
.doc = "Network interface that will be used to search for"
1805
{ .name = "seckey", .key = 's',
1807
.doc = "OpenPGP secret key file base name",
1809
{ .name = "pubkey", .key = 'p',
1811
.doc = "OpenPGP public key file base name",
1813
{ .name = "dh-bits", .key = 129,
1815
.doc = "Bit length of the prime number used in the"
1816
" Diffie-Hellman key exchange",
1818
{ .name = "priority", .key = 130,
1820
.doc = "GnuTLS priority string for the TLS handshake",
1822
{ .name = "delay", .key = 131,
1824
.doc = "Maximum delay to wait for interface startup",
1826
{ .name = "retry", .key = 132,
1828
.doc = "Retry interval used when denied by the Mandos server",
1830
{ .name = "network-hook-dir", .key = 133,
1832
.doc = "Directory where network hooks are located",
1835
* These reproduce what we would get without ARGP_NO_HELP
1837
{ .name = "help", .key = '?',
1838
.doc = "Give this help list", .group = -1 },
1839
{ .name = "usage", .key = -3,
1840
.doc = "Give a short usage message", .group = -1 },
1841
{ .name = "version", .key = 'V',
1842
.doc = "Print program version", .group = -1 },
1846
error_t parse_opt(int key, char *arg,
1847
struct argp_state *state){
1850
case 128: /* --debug */
1853
case 'c': /* --connect */
1856
case 'i': /* --interface */
1857
ret_errno = argz_add_sep(&interfaces, &interfaces_size, arg,
1860
argp_error(state, "%s", strerror(ret_errno));
1863
case 's': /* --seckey */
1866
case 'p': /* --pubkey */
1869
case 129: /* --dh-bits */
1871
tmpmax = strtoimax(arg, &tmp, 10);
1872
if(errno != 0 or tmp == arg or *tmp != '\0'
1873
or tmpmax != (typeof(mc.dh_bits))tmpmax){
1874
argp_error(state, "Bad number of DH bits");
1876
mc.dh_bits = (typeof(mc.dh_bits))tmpmax;
1878
case 130: /* --priority */
1881
case 131: /* --delay */
1883
delay = strtof(arg, &tmp);
1884
if(errno != 0 or tmp == arg or *tmp != '\0'){
1885
argp_error(state, "Bad delay");
1887
case 132: /* --retry */
1889
retry_interval = strtod(arg, &tmp);
1890
if(errno != 0 or tmp == arg or *tmp != '\0'
1891
or (retry_interval * 1000) > INT_MAX
1892
or retry_interval < 0){
1893
argp_error(state, "Bad retry interval");
1896
case 133: /* --network-hook-dir */
1900
* These reproduce what we would get without ARGP_NO_HELP
1902
case '?': /* --help */
1903
argp_state_help(state, state->out_stream,
1904
(ARGP_HELP_STD_HELP | ARGP_HELP_EXIT_ERR)
1905
& ~(unsigned int)ARGP_HELP_EXIT_OK);
1906
case -3: /* --usage */
1907
argp_state_help(state, state->out_stream,
1908
ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);
1909
case 'V': /* --version */
1910
fprintf_plus(state->out_stream, "%s\n", argp_program_version);
1911
exit(argp_err_exit_status);
1914
return ARGP_ERR_UNKNOWN;
1919
struct argp argp = { .options = options, .parser = parse_opt,
1921
.doc = "Mandos client -- Get and decrypt"
1922
" passwords from a Mandos server" };
1923
ret = argp_parse(&argp, argc, argv,
1924
ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);
1931
perror_plus("argp_parse");
1932
exitcode = EX_OSERR;
1935
exitcode = EX_USAGE;
1941
/* Work around Debian bug #633582:
1942
<http://bugs.debian.org/633582> */
1944
/* Re-raise priviliges */
1945
if(raise_privileges() == 0){
1948
if(strcmp(seckey, PATHDIR "/" SECKEY) == 0){
1949
int seckey_fd = open(seckey, O_RDONLY);
1950
if(seckey_fd == -1){
1951
perror_plus("open");
1953
ret = (int)TEMP_FAILURE_RETRY(fstat(seckey_fd, &st));
1955
perror_plus("fstat");
1957
if(S_ISREG(st.st_mode)
1958
and st.st_uid == 0 and st.st_gid == 0){
1959
ret = fchown(seckey_fd, uid, gid);
1961
perror_plus("fchown");
1965
TEMP_FAILURE_RETRY(close(seckey_fd));
1969
if(strcmp(pubkey, PATHDIR "/" PUBKEY) == 0){
1970
int pubkey_fd = open(pubkey, O_RDONLY);
1971
if(pubkey_fd == -1){
1972
perror_plus("open");
1974
ret = (int)TEMP_FAILURE_RETRY(fstat(pubkey_fd, &st));
1976
perror_plus("fstat");
1978
if(S_ISREG(st.st_mode)
1979
and st.st_uid == 0 and st.st_gid == 0){
1980
ret = fchown(pubkey_fd, uid, gid);
1982
perror_plus("fchown");
1986
TEMP_FAILURE_RETRY(close(pubkey_fd));
1990
/* Lower privileges */
1994
perror_plus("seteuid");
1999
/* Remove empty interface names */
2001
char *interface = NULL;
2002
while((interface = argz_next(interfaces, interfaces_size,
2004
if(if_nametoindex(interface) == 0){
2005
if(interface[0] != '\0' and strcmp(interface, "none") != 0){
2006
fprintf_plus(stderr, "Not using nonexisting interface"
2007
" \"%s\"\n", interface);
2009
argz_delete(&interfaces, &interfaces_size, interface);
2015
/* Run network hooks */
2017
ret_errno = argz_append(&interfaces_hooks, &interfaces_hooks_size,
2018
interfaces, interfaces_size);
2021
perror_plus("argz_append");
2024
argz_stringify(interfaces_hooks, interfaces_hooks_size, (int)',');
2025
if(not run_network_hooks("start", interfaces_hooks, delay)){
421
static AvahiSimplePoll *simple_poll = NULL;
422
static AvahiServer *server = NULL;
424
static void resolve_callback(
425
AvahiSServiceResolver *r,
426
AVAHI_GCC_UNUSED AvahiIfIndex interface,
427
AVAHI_GCC_UNUSED AvahiProtocol protocol,
428
AvahiResolverEvent event,
432
const char *host_name,
433
const AvahiAddress *address,
435
AvahiStringList *txt,
436
AvahiLookupResultFlags flags,
437
AVAHI_GCC_UNUSED void* userdata) {
441
/* Called whenever a service has been resolved successfully or timed out */
444
case AVAHI_RESOLVER_FAILURE:
445
fprintf(stderr, "(Resolver) Failed to resolve service '%s' of type '%s' in domain '%s': %s\n", name, type, domain, avahi_strerror(avahi_server_errno(server)));
448
case AVAHI_RESOLVER_FOUND: {
449
char ip[AVAHI_ADDRESS_STR_MAX];
450
avahi_address_snprint(ip, sizeof(ip), address);
451
int ret = start_mandos_communcation(ip, port);
459
avahi_s_service_resolver_free(r);
462
static void browse_callback(
463
AvahiSServiceBrowser *b,
464
AvahiIfIndex interface,
465
AvahiProtocol protocol,
466
AvahiBrowserEvent event,
470
AVAHI_GCC_UNUSED AvahiLookupResultFlags flags,
473
AvahiServer *s = userdata;
476
/* Called whenever a new services becomes available on the LAN or is removed from the LAN */
480
case AVAHI_BROWSER_FAILURE:
482
fprintf(stderr, "(Browser) %s\n", avahi_strerror(avahi_server_errno(server)));
483
avahi_simple_poll_quit(simple_poll);
486
case AVAHI_BROWSER_NEW:
487
/* We ignore the returned resolver object. In the callback
488
function we free it. If the server is terminated before
489
the callback function is called the server will free
490
the resolver for us. */
492
if (!(avahi_s_service_resolver_new(s, interface, protocol, name, type, domain, AVAHI_PROTO_INET6, 0, resolve_callback, s)))
493
fprintf(stderr, "Failed to resolve service '%s': %s\n", name, avahi_strerror(avahi_server_errno(s)));
497
case AVAHI_BROWSER_REMOVE:
500
case AVAHI_BROWSER_ALL_FOR_NOW:
501
case AVAHI_BROWSER_CACHE_EXHAUSTED:
506
int main(AVAHI_GCC_UNUSED int argc, AVAHI_GCC_UNUSED char*argv[]) {
507
AvahiServerConfig config;
508
AvahiSServiceBrowser *sb = NULL;
2031
512
avahi_set_log_function(empty_log);
2034
/* Initialize Avahi early so avahi_simple_poll_quit() can be called
2035
from the signal handler */
2036
/* Initialize the pseudo-RNG for Avahi */
2037
srand((unsigned int) time(NULL));
2038
mc.simple_poll = avahi_simple_poll_new();
2039
if(mc.simple_poll == NULL){
2040
fprintf_plus(stderr,
2041
"Avahi: Failed to create simple poll object.\n");
2042
exitcode = EX_UNAVAILABLE;
2046
sigemptyset(&sigterm_action.sa_mask);
2047
ret = sigaddset(&sigterm_action.sa_mask, SIGINT);
2049
perror_plus("sigaddset");
2050
exitcode = EX_OSERR;
2053
ret = sigaddset(&sigterm_action.sa_mask, SIGHUP);
2055
perror_plus("sigaddset");
2056
exitcode = EX_OSERR;
2059
ret = sigaddset(&sigterm_action.sa_mask, SIGTERM);
2061
perror_plus("sigaddset");
2062
exitcode = EX_OSERR;
2065
/* Need to check if the handler is SIG_IGN before handling:
2066
| [[info:libc:Initial Signal Actions]] |
2067
| [[info:libc:Basic Signal Handling]] |
2069
ret = sigaction(SIGINT, NULL, &old_sigterm_action);
2071
perror_plus("sigaction");
2074
if(old_sigterm_action.sa_handler != SIG_IGN){
2075
ret = sigaction(SIGINT, &sigterm_action, NULL);
2077
perror_plus("sigaction");
2078
exitcode = EX_OSERR;
2082
ret = sigaction(SIGHUP, NULL, &old_sigterm_action);
2084
perror_plus("sigaction");
2087
if(old_sigterm_action.sa_handler != SIG_IGN){
2088
ret = sigaction(SIGHUP, &sigterm_action, NULL);
2090
perror_plus("sigaction");
2091
exitcode = EX_OSERR;
2095
ret = sigaction(SIGTERM, NULL, &old_sigterm_action);
2097
perror_plus("sigaction");
2100
if(old_sigterm_action.sa_handler != SIG_IGN){
2101
ret = sigaction(SIGTERM, &sigterm_action, NULL);
2103
perror_plus("sigaction");
2104
exitcode = EX_OSERR;
2109
/* If no interfaces were specified, make a list */
2110
if(interfaces == NULL){
2111
struct dirent **direntries;
2112
/* Look for any good interfaces */
2113
ret = scandir(sys_class_net, &direntries, good_interface,
2116
/* Add all found interfaces to interfaces list */
2117
for(int i = 0; i < ret; ++i){
2118
ret_errno = argz_add(&interfaces, &interfaces_size,
2119
direntries[i]->d_name);
2121
perror_plus("argz_add");
2125
fprintf_plus(stderr, "Will use interface \"%s\"\n",
2126
direntries[i]->d_name);
2132
fprintf_plus(stderr, "Could not find a network interface\n");
2133
exitcode = EXIT_FAILURE;
2138
/* If we only got one interface, explicitly use only that one */
2139
if(argz_count(interfaces, interfaces_size) == 1){
2141
fprintf_plus(stderr, "Using only interface \"%s\"\n",
2144
if_index = (AvahiIfIndex)if_nametoindex(interfaces);
2147
/* Bring up interfaces which are down */
2148
if(not (argz_count(interfaces, interfaces_size) == 1
2149
and strcmp(interfaces, "none") == 0)){
2150
char *interface = NULL;
2151
while((interface = argz_next(interfaces, interfaces_size,
2153
bool interface_was_up = interface_is_up(interface);
2154
ret = bring_up_interface(interface, delay);
2155
if(not interface_was_up){
2158
perror_plus("Failed to bring up interface");
2160
ret_errno = argz_add(&interfaces_to_take_down,
2161
&interfaces_to_take_down_size,
2168
interfaces_size = 0;
2169
if(debug and (interfaces_to_take_down == NULL)){
2170
fprintf_plus(stderr, "No interfaces were brought up\n");
2178
ret = init_gnutls_global(pubkey, seckey);
2180
fprintf_plus(stderr, "init_gnutls_global failed\n");
2181
exitcode = EX_UNAVAILABLE;
2184
gnutls_initialized = true;
2191
if(mkdtemp(tempdir) == NULL){
2192
perror_plus("mkdtemp");
2195
tempdir_created = true;
2201
if(not init_gpgme(pubkey, seckey, tempdir)){
2202
fprintf_plus(stderr, "init_gpgme failed\n");
2203
exitcode = EX_UNAVAILABLE;
2206
gpgme_initialized = true;
2213
if(connect_to != NULL){
2214
/* Connect directly, do not use Zeroconf */
2215
/* (Mainly meant for debugging) */
2216
char *address = strrchr(connect_to, ':');
2218
if(address == NULL){
2219
fprintf_plus(stderr, "No colon in address\n");
2220
exitcode = EX_USAGE;
2230
tmpmax = strtoimax(address+1, &tmp, 10);
2231
if(errno != 0 or tmp == address+1 or *tmp != '\0'
2232
or tmpmax != (uint16_t)tmpmax){
2233
fprintf_plus(stderr, "Bad port number\n");
2234
exitcode = EX_USAGE;
2242
port = (uint16_t)tmpmax;
2244
/* Colon in address indicates IPv6 */
2246
if(strchr(connect_to, ':') != NULL){
2248
/* Accept [] around IPv6 address - see RFC 5952 */
2249
if(connect_to[0] == '[' and address[-1] == ']')
2257
address = connect_to;
2263
while(not quit_now){
2264
ret = start_mandos_communication(address, port, if_index, af);
2265
if(quit_now or ret == 0){
2269
fprintf_plus(stderr, "Retrying in %d seconds\n",
2270
(int)retry_interval);
2272
sleep((int)retry_interval);
2276
exitcode = EXIT_SUCCESS;
2287
AvahiServerConfig config;
2288
/* Do not publish any local Zeroconf records */
514
/* Initialize the psuedo-RNG */
517
/* Allocate main loop object */
518
if (!(simple_poll = avahi_simple_poll_new())) {
519
fprintf(stderr, "Failed to create simple poll object.\n");
523
/* Do not publish any local records */
2289
524
avahi_server_config_init(&config);
2290
525
config.publish_hinfo = 0;
2291
526
config.publish_addresses = 0;
2292
527
config.publish_workstation = 0;
2293
528
config.publish_domain = 0;
530
/* /\* Set a unicast DNS server for wide area DNS-SD *\/ */
531
/* avahi_address_parse("193.11.177.11", AVAHI_PROTO_UNSPEC, &config.wide_area_servers[0]); */
532
/* config.n_wide_area_servers = 1; */
533
/* config.enable_wide_area = 1; */
2295
535
/* Allocate a new server */
2296
mc.server = avahi_server_new(avahi_simple_poll_get
2297
(mc.simple_poll), &config, NULL,
2300
/* Free the Avahi configuration data */
536
server = avahi_server_new(avahi_simple_poll_get(simple_poll), &config, NULL, NULL, &error);
538
/* Free the configuration data */
2301
539
avahi_server_config_free(&config);
2304
/* Check if creating the Avahi server object succeeded */
2305
if(mc.server == NULL){
2306
fprintf_plus(stderr, "Failed to create Avahi server: %s\n",
2307
avahi_strerror(ret_errno));
2308
exitcode = EX_UNAVAILABLE;
2316
/* Create the Avahi service browser */
2317
sb = avahi_s_service_browser_new(mc.server, if_index,
2318
AVAHI_PROTO_UNSPEC, "_mandos._tcp",
2319
NULL, 0, browse_callback, NULL);
2321
fprintf_plus(stderr, "Failed to create service browser: %s\n",
2322
avahi_strerror(avahi_server_errno(mc.server)));
2323
exitcode = EX_UNAVAILABLE;
2331
/* Run the main loop */
2334
fprintf_plus(stderr, "Starting Avahi loop search\n");
2337
ret = avahi_loop_with_timeout(mc.simple_poll,
2338
(int)(retry_interval * 1000));
2340
fprintf_plus(stderr, "avahi_loop_with_timeout exited %s\n",
2341
(ret == 0) ? "successfully" : "with error");
2347
fprintf_plus(stderr, "%s exiting\n", argv[0]);
2350
/* Cleanup things */
2352
avahi_s_service_browser_free(sb);
2354
if(mc.server != NULL)
2355
avahi_server_free(mc.server);
2357
if(mc.simple_poll != NULL)
2358
avahi_simple_poll_free(mc.simple_poll);
2360
if(gnutls_initialized){
2361
gnutls_certificate_free_credentials(mc.cred);
2362
gnutls_global_deinit();
2363
gnutls_dh_params_deinit(mc.dh_params);
2366
if(gpgme_initialized){
2367
gpgme_release(mc.ctx);
2370
/* Cleans up the circular linked list of Mandos servers the client
2372
if(mc.current_server != NULL){
2373
mc.current_server->prev->next = NULL;
2374
while(mc.current_server != NULL){
2375
server *next = mc.current_server->next;
2376
free(mc.current_server);
2377
mc.current_server = next;
2381
/* Re-raise priviliges */
2385
/* Run network hooks */
2386
run_network_hooks("stop", interfaces_hooks, delay);
2388
/* Take down the network interfaces which were brought up */
2390
char *interface = NULL;
2391
while((interface=argz_next(interfaces_to_take_down,
2392
interfaces_to_take_down_size,
2394
ret_errno = take_down_interface(interface);
2397
perror_plus("Failed to take down interface");
2400
if(debug and (interfaces_to_take_down == NULL)){
2401
fprintf_plus(stderr, "No interfaces needed to be taken"
2406
lower_privileges_permanently();
2409
free(interfaces_to_take_down);
2410
free(interfaces_hooks);
2412
/* Removes the GPGME temp directory and all files inside */
2413
if(tempdir_created){
2414
struct dirent **direntries = NULL;
2415
struct dirent *direntry = NULL;
2416
int numentries = scandir(tempdir, &direntries, notdotentries,
2418
if (numentries > 0){
2419
for(int i = 0; i < numentries; i++){
2420
direntry = direntries[i];
2421
char *fullname = NULL;
2422
ret = asprintf(&fullname, "%s/%s", tempdir,
2425
perror_plus("asprintf");
2428
ret = remove(fullname);
2430
fprintf_plus(stderr, "remove(\"%s\"): %s\n", fullname,
2437
/* need to clean even if 0 because man page doesn't specify */
2439
if (numentries == -1){
2440
perror_plus("scandir");
2442
ret = rmdir(tempdir);
2443
if(ret == -1 and errno != ENOENT){
2444
perror_plus("rmdir");
2449
sigemptyset(&old_sigterm_action.sa_mask);
2450
old_sigterm_action.sa_handler = SIG_DFL;
2451
ret = (int)TEMP_FAILURE_RETRY(sigaction(signal_received,
2452
&old_sigterm_action,
2455
perror_plus("sigaction");
2458
ret = raise(signal_received);
2459
} while(ret != 0 and errno == EINTR);
2461
perror_plus("raise");
2464
TEMP_FAILURE_RETRY(pause());
541
/* Check wether creating the server object succeeded */
543
fprintf(stderr, "Failed to create server: %s\n", avahi_strerror(error));
547
/* Create the service browser */
548
if (!(sb = avahi_s_service_browser_new(server, if_nametoindex("eth0"), AVAHI_PROTO_INET6, "_mandos._tcp", NULL, 0, browse_callback, server))) {
549
fprintf(stderr, "Failed to create service browser: %s\n", avahi_strerror(avahi_server_errno(server)));
553
/* Run the main loop */
554
avahi_simple_poll_loop(simple_poll);
562
avahi_s_service_browser_free(sb);
565
avahi_server_free(server);
568
avahi_simple_poll_free(simple_poll);