107
49
#include <avahi-common/malloc.h>
108
50
#include <avahi-common/error.h>
111
#include <gnutls/gnutls.h> /* All GnuTLS types, constants and
114
init_gnutls_session(),
116
#include <gnutls/openpgp.h>
117
/* gnutls_certificate_set_openpgp_key_file(),
118
GNUTLS_OPENPGP_FMT_BASE64 */
121
#include <gpgme.h> /* All GPGME types, constants and
124
GPGME_PROTOCOL_OpenPGP,
53
#include <sys/types.h> /* socket(), inet_pton() */
54
#include <sys/socket.h> /* socket(), struct sockaddr_in6,
55
struct in6_addr, inet_pton() */
56
#include <gnutls/gnutls.h> /* All GnuTLS stuff */
57
#include <gnutls/openpgp.h> /* GnuTLS with openpgp stuff */
59
#include <unistd.h> /* close() */
60
#include <netinet/in.h>
61
#include <stdbool.h> /* true */
62
#include <string.h> /* memset */
63
#include <arpa/inet.h> /* inet_pton() */
64
#include <iso646.h> /* not */
67
#include <errno.h> /* perror() */
127
73
#define BUFFER_SIZE 256
129
#define PATHDIR "/conf/conf.d/mandos"
130
#define SECKEY "seckey.txt"
131
#define PUBKEY "pubkey.txt"
132
#define HOOKDIR "/lib/mandos/network-hooks.d"
75
static const char *keydir = "/conf/conf.d/mandos";
76
static const char *pubkeyfile = "pubkey.txt";
77
static const char *seckeyfile = "seckey.txt";
134
79
bool debug = false;
135
static const char mandos_protocol_version[] = "1";
136
const char *argp_program_version = "mandos-client " VERSION;
137
const char *argp_program_bug_address = "<mandos@recompile.se>";
138
static const char sys_class_net[] = "/sys/class/net";
139
char *connect_to = NULL;
140
const char *hookdir = HOOKDIR;
144
/* Doubly linked list that need to be circularly linked when used */
145
typedef struct server{
148
AvahiIfIndex if_index;
150
struct timespec last_seen;
155
/* Used for passing in values through the Avahi callback functions */
81
/* Used for passing in values through all the callback functions */
83
AvahiSimplePoll *simple_poll;
157
84
AvahiServer *server;
158
85
gnutls_certificate_credentials_t cred;
159
86
unsigned int dh_bits;
160
gnutls_dh_params_t dh_params;
161
87
const char *priority;
91
* Decrypt OpenPGP data using keyrings in HOMEDIR.
94
static ssize_t pgp_packet_decrypt (const char *cryptotext,
98
gpgme_data_t dh_crypto, dh_plain;
163
server *current_server;
165
size_t interfaces_size;
168
/* global so signal handler can reach it*/
169
AvahiSimplePoll *simple_poll;
171
sig_atomic_t quit_now = 0;
172
int signal_received = 0;
174
/* Function to use when printing errors */
175
void perror_plus(const char *print_text){
177
fprintf(stderr, "Mandos plugin %s: ",
178
program_invocation_short_name);
183
__attribute__((format (gnu_printf, 2, 3)))
184
int fprintf_plus(FILE *stream, const char *format, ...){
186
va_start (ap, format);
188
TEMP_FAILURE_RETRY(fprintf(stream, "Mandos plugin %s: ",
189
program_invocation_short_name));
190
return (int)TEMP_FAILURE_RETRY(vfprintf(stream, format, ap));
194
* Make additional room in "buffer" for at least BUFFER_SIZE more
195
* bytes. "buffer_capacity" is how much is currently allocated,
196
* "buffer_length" is how much is already used.
198
size_t incbuffer(char **buffer, size_t buffer_length,
199
size_t buffer_capacity){
200
if(buffer_length + BUFFER_SIZE > buffer_capacity){
201
*buffer = realloc(*buffer, buffer_capacity + BUFFER_SIZE);
205
buffer_capacity += BUFFER_SIZE;
207
return buffer_capacity;
210
/* Add server to set of servers to retry periodically */
211
bool add_server(const char *ip, in_port_t port, AvahiIfIndex if_index,
212
int af, server **current_server){
214
server *new_server = malloc(sizeof(server));
215
if(new_server == NULL){
216
perror_plus("malloc");
219
*new_server = (server){ .ip = strdup(ip),
221
.if_index = if_index,
223
if(new_server->ip == NULL){
224
perror_plus("strdup");
227
/* Special case of first server */
228
if(*current_server == NULL){
229
new_server->next = new_server;
230
new_server->prev = new_server;
231
*current_server = new_server;
232
/* Place the new server last in the list */
234
new_server->next = *current_server;
235
new_server->prev = (*current_server)->prev;
236
new_server->prev->next = new_server;
237
(*current_server)->prev = new_server;
239
ret = clock_gettime(CLOCK_MONOTONIC, &(*current_server)->last_seen);
241
perror_plus("clock_gettime");
250
static bool init_gpgme(const char *seckey, const char *pubkey,
251
const char *tempdir, mandos_context *mc){
252
100
gpgme_error_t rc;
102
ssize_t plaintext_capacity = 0;
103
ssize_t plaintext_length = 0;
253
104
gpgme_engine_info_t engine_info;
256
* Helper function to insert pub and seckey to the engine keyring.
258
bool import_key(const char *filename){
261
gpgme_data_t pgp_data;
263
fd = (int)TEMP_FAILURE_RETRY(open(filename, O_RDONLY));
269
rc = gpgme_data_new_from_fd(&pgp_data, fd);
270
if(rc != GPG_ERR_NO_ERROR){
271
fprintf_plus(stderr, "bad gpgme_data_new_from_fd: %s: %s\n",
272
gpgme_strsource(rc), gpgme_strerror(rc));
276
rc = gpgme_op_import(mc->ctx, pgp_data);
277
if(rc != GPG_ERR_NO_ERROR){
278
fprintf_plus(stderr, "bad gpgme_op_import: %s: %s\n",
279
gpgme_strsource(rc), gpgme_strerror(rc));
283
ret = (int)TEMP_FAILURE_RETRY(close(fd));
285
perror_plus("close");
287
gpgme_data_release(pgp_data);
292
fprintf_plus(stderr, "Initializing GPGME\n");
107
fprintf(stderr, "Trying to decrypt OpenPGP data\n");
296
111
gpgme_check_version(NULL);
297
112
rc = gpgme_engine_check_version(GPGME_PROTOCOL_OpenPGP);
298
if(rc != GPG_ERR_NO_ERROR){
299
fprintf_plus(stderr, "bad gpgme_engine_check_version: %s: %s\n",
300
gpgme_strsource(rc), gpgme_strerror(rc));
113
if (rc != GPG_ERR_NO_ERROR){
114
fprintf(stderr, "bad gpgme_engine_check_version: %s: %s\n",
115
gpgme_strsource(rc), gpgme_strerror(rc));
304
119
/* Set GPGME home directory for the OpenPGP engine only */
305
rc = gpgme_get_engine_info(&engine_info);
306
if(rc != GPG_ERR_NO_ERROR){
307
fprintf_plus(stderr, "bad gpgme_get_engine_info: %s: %s\n",
308
gpgme_strsource(rc), gpgme_strerror(rc));
120
rc = gpgme_get_engine_info (&engine_info);
121
if (rc != GPG_ERR_NO_ERROR){
122
fprintf(stderr, "bad gpgme_get_engine_info: %s: %s\n",
123
gpgme_strsource(rc), gpgme_strerror(rc));
311
126
while(engine_info != NULL){
312
127
if(engine_info->protocol == GPGME_PROTOCOL_OpenPGP){
313
128
gpgme_set_engine_info(GPGME_PROTOCOL_OpenPGP,
314
engine_info->file_name, tempdir);
129
engine_info->file_name, homedir);
317
132
engine_info = engine_info->next;
319
134
if(engine_info == NULL){
320
fprintf_plus(stderr, "Could not set GPGME home dir to %s\n",
325
/* Create new GPGME "context" */
326
rc = gpgme_new(&(mc->ctx));
327
if(rc != GPG_ERR_NO_ERROR){
328
fprintf_plus(stderr, "Mandos plugin mandos-client: "
329
"bad gpgme_new: %s: %s\n", gpgme_strsource(rc),
334
if(not import_key(pubkey) or not import_key(seckey)){
342
* Decrypt OpenPGP data.
343
* Returns -1 on error
345
static ssize_t pgp_packet_decrypt(const char *cryptotext,
349
gpgme_data_t dh_crypto, dh_plain;
352
size_t plaintext_capacity = 0;
353
ssize_t plaintext_length = 0;
356
fprintf_plus(stderr, "Trying to decrypt OpenPGP data\n");
135
fprintf(stderr, "Could not set GPGME home dir to %s\n", homedir);
359
139
/* Create new GPGME data buffer from memory cryptotext */
360
140
rc = gpgme_data_new_from_mem(&dh_crypto, cryptotext, crypto_size,
362
if(rc != GPG_ERR_NO_ERROR){
363
fprintf_plus(stderr, "bad gpgme_data_new_from_mem: %s: %s\n",
364
gpgme_strsource(rc), gpgme_strerror(rc));
142
if (rc != GPG_ERR_NO_ERROR){
143
fprintf(stderr, "bad gpgme_data_new_from_mem: %s: %s\n",
144
gpgme_strsource(rc), gpgme_strerror(rc));
368
148
/* Create new empty GPGME data buffer for the plaintext */
369
149
rc = gpgme_data_new(&dh_plain);
370
if(rc != GPG_ERR_NO_ERROR){
371
fprintf_plus(stderr, "Mandos plugin mandos-client: "
372
"bad gpgme_data_new: %s: %s\n",
373
gpgme_strsource(rc), gpgme_strerror(rc));
150
if (rc != GPG_ERR_NO_ERROR){
151
fprintf(stderr, "bad gpgme_data_new: %s: %s\n",
152
gpgme_strsource(rc), gpgme_strerror(rc));
374
153
gpgme_data_release(dh_crypto);
157
/* Create new GPGME "context" */
158
rc = gpgme_new(&ctx);
159
if (rc != GPG_ERR_NO_ERROR){
160
fprintf(stderr, "bad gpgme_new: %s: %s\n",
161
gpgme_strsource(rc), gpgme_strerror(rc));
162
plaintext_length = -1;
378
166
/* Decrypt data from the cryptotext data buffer to the plaintext
380
rc = gpgme_op_decrypt(mc->ctx, dh_crypto, dh_plain);
381
if(rc != GPG_ERR_NO_ERROR){
382
fprintf_plus(stderr, "bad gpgme_op_decrypt: %s: %s\n",
383
gpgme_strsource(rc), gpgme_strerror(rc));
168
rc = gpgme_op_decrypt(ctx, dh_crypto, dh_plain);
169
if (rc != GPG_ERR_NO_ERROR){
170
fprintf(stderr, "bad gpgme_op_decrypt: %s: %s\n",
171
gpgme_strsource(rc), gpgme_strerror(rc));
384
172
plaintext_length = -1;
386
gpgme_decrypt_result_t result;
387
result = gpgme_op_decrypt_result(mc->ctx);
389
fprintf_plus(stderr, "gpgme_op_decrypt_result failed\n");
391
fprintf_plus(stderr, "Unsupported algorithm: %s\n",
392
result->unsupported_algorithm);
393
fprintf_plus(stderr, "Wrong key usage: %u\n",
394
result->wrong_key_usage);
395
if(result->file_name != NULL){
396
fprintf_plus(stderr, "File name: %s\n", result->file_name);
398
gpgme_recipient_t recipient;
399
recipient = result->recipients;
177
fprintf(stderr, "Decryption of OpenPGP data succeeded\n");
181
gpgme_decrypt_result_t result;
182
result = gpgme_op_decrypt_result(ctx);
184
fprintf(stderr, "gpgme_op_decrypt_result failed\n");
186
fprintf(stderr, "Unsupported algorithm: %s\n",
187
result->unsupported_algorithm);
188
fprintf(stderr, "Wrong key usage: %d\n",
189
result->wrong_key_usage);
190
if(result->file_name != NULL){
191
fprintf(stderr, "File name: %s\n", result->file_name);
193
gpgme_recipient_t recipient;
194
recipient = result->recipients;
400
196
while(recipient != NULL){
401
fprintf_plus(stderr, "Public key algorithm: %s\n",
402
gpgme_pubkey_algo_name
403
(recipient->pubkey_algo));
404
fprintf_plus(stderr, "Key ID: %s\n", recipient->keyid);
405
fprintf_plus(stderr, "Secret key available: %s\n",
406
recipient->status == GPG_ERR_NO_SECKEY
197
fprintf(stderr, "Public key algorithm: %s\n",
198
gpgme_pubkey_algo_name(recipient->pubkey_algo));
199
fprintf(stderr, "Key ID: %s\n", recipient->keyid);
200
fprintf(stderr, "Secret key available: %s\n",
201
recipient->status == GPG_ERR_NO_SECKEY
408
203
recipient = recipient->next;
416
fprintf_plus(stderr, "Decryption of OpenPGP data succeeded\n");
419
209
/* Seek back to the beginning of the GPGME plaintext data buffer */
420
if(gpgme_data_seek(dh_plain, (off_t)0, SEEK_SET) == -1){
421
perror_plus("gpgme_data_seek");
210
if (gpgme_data_seek(dh_plain, (off_t) 0, SEEK_SET) == -1){
211
perror("pgpme_data_seek");
422
212
plaintext_length = -1;
423
213
goto decrypt_end;
426
216
*plaintext = NULL;
428
plaintext_capacity = incbuffer(plaintext,
429
(size_t)plaintext_length,
431
if(plaintext_capacity == 0){
432
perror_plus("incbuffer");
433
plaintext_length = -1;
218
if (plaintext_length + BUFFER_SIZE > plaintext_capacity){
219
*plaintext = realloc(*plaintext,
220
(unsigned int)plaintext_capacity
222
if (*plaintext == NULL){
224
plaintext_length = -1;
227
plaintext_capacity += BUFFER_SIZE;
437
230
ret = gpgme_data_read(dh_plain, *plaintext + plaintext_length,
439
232
/* Print the data, if any */
445
perror_plus("gpgme_data_read");
238
perror("gpgme_data_read");
446
239
plaintext_length = -1;
447
240
goto decrypt_end;
449
242
plaintext_length += ret;
453
fprintf_plus(stderr, "Decrypted password is: ");
454
for(ssize_t i = 0; i < plaintext_length; i++){
246
fprintf(stderr, "Decrypted password is: ");
247
for(size_t i = 0; i < plaintext_length; i++){
455
248
fprintf(stderr, "%02hhX ", (*plaintext)[i]);
457
250
fprintf(stderr, "\n");
467
260
return plaintext_length;
470
static const char * safer_gnutls_strerror(int value){
471
const char *ret = gnutls_strerror(value);
263
static const char * safer_gnutls_strerror (int value) {
264
const char *ret = gnutls_strerror (value);
473
266
ret = "(unknown)";
477
/* GnuTLS log function callback */
478
270
static void debuggnutls(__attribute__((unused)) int level,
479
271
const char* string){
480
fprintf_plus(stderr, "GnuTLS: %s", string);
272
fprintf(stderr, "%s", string);
483
static int init_gnutls_global(const char *pubkeyfilename,
484
const char *seckeyfilename,
275
static int initgnutls(mandos_context *mc, gnutls_session_t *session,
276
gnutls_dh_params_t *dh_params){
489
fprintf_plus(stderr, "Initializing GnuTLS\n");
281
fprintf(stderr, "Initializing GnuTLS\n");
492
ret = gnutls_global_init();
493
if(ret != GNUTLS_E_SUCCESS){
494
fprintf_plus(stderr, "GnuTLS global_init: %s\n",
495
safer_gnutls_strerror(ret));
284
if ((ret = gnutls_global_init ())
285
!= GNUTLS_E_SUCCESS) {
286
fprintf (stderr, "global_init: %s\n", safer_gnutls_strerror(ret));
500
/* "Use a log level over 10 to enable all debugging options."
503
291
gnutls_global_set_log_level(11);
504
292
gnutls_global_set_log_function(debuggnutls);
507
/* OpenPGP credentials */
508
ret = gnutls_certificate_allocate_credentials(&mc->cred);
509
if(ret != GNUTLS_E_SUCCESS){
510
fprintf_plus(stderr, "GnuTLS memory error: %s\n",
511
safer_gnutls_strerror(ret));
512
gnutls_global_deinit();
295
/* openpgp credentials */
296
if ((ret = gnutls_certificate_allocate_credentials (&mc->cred))
297
!= GNUTLS_E_SUCCESS) {
298
fprintf (stderr, "memory error: %s\n",
299
safer_gnutls_strerror(ret));
517
fprintf_plus(stderr, "Attempting to use OpenPGP public key %s and"
518
" secret key %s as GnuTLS credentials\n",
304
fprintf(stderr, "Attempting to use OpenPGP certificate %s"
305
" and keyfile %s as GnuTLS credentials\n", pubkeyfile,
523
309
ret = gnutls_certificate_set_openpgp_key_file
524
(mc->cred, pubkeyfilename, seckeyfilename,
525
GNUTLS_OPENPGP_FMT_BASE64);
526
if(ret != GNUTLS_E_SUCCESS){
528
"Error[%d] while reading the OpenPGP key pair ('%s',"
529
" '%s')\n", ret, pubkeyfilename, seckeyfilename);
530
fprintf_plus(stderr, "The GnuTLS error is: %s\n",
531
safer_gnutls_strerror(ret));
535
/* GnuTLS server initialization */
536
ret = gnutls_dh_params_init(&mc->dh_params);
537
if(ret != GNUTLS_E_SUCCESS){
538
fprintf_plus(stderr, "Error in GnuTLS DH parameter"
539
" initialization: %s\n",
540
safer_gnutls_strerror(ret));
543
ret = gnutls_dh_params_generate2(mc->dh_params, mc->dh_bits);
544
if(ret != GNUTLS_E_SUCCESS){
545
fprintf_plus(stderr, "Error in GnuTLS prime generation: %s\n",
546
safer_gnutls_strerror(ret));
550
gnutls_certificate_set_dh_params(mc->cred, mc->dh_params);
556
gnutls_certificate_free_credentials(mc->cred);
557
gnutls_global_deinit();
558
gnutls_dh_params_deinit(mc->dh_params);
562
static int init_gnutls_session(gnutls_session_t *session,
565
/* GnuTLS session creation */
567
ret = gnutls_init(session, GNUTLS_SERVER);
571
} while(ret == GNUTLS_E_INTERRUPTED or ret == GNUTLS_E_AGAIN);
572
if(ret != GNUTLS_E_SUCCESS){
574
"Error in GnuTLS session initialization: %s\n",
575
safer_gnutls_strerror(ret));
581
ret = gnutls_priority_set_direct(*session, mc->priority, &err);
583
gnutls_deinit(*session);
586
} while(ret == GNUTLS_E_INTERRUPTED or ret == GNUTLS_E_AGAIN);
587
if(ret != GNUTLS_E_SUCCESS){
588
fprintf_plus(stderr, "Syntax error at: %s\n", err);
589
fprintf_plus(stderr, "GnuTLS error: %s\n",
590
safer_gnutls_strerror(ret));
591
gnutls_deinit(*session);
597
ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,
600
gnutls_deinit(*session);
603
} while(ret == GNUTLS_E_INTERRUPTED or ret == GNUTLS_E_AGAIN);
604
if(ret != GNUTLS_E_SUCCESS){
605
fprintf_plus(stderr, "Error setting GnuTLS credentials: %s\n",
606
safer_gnutls_strerror(ret));
607
gnutls_deinit(*session);
310
(mc->cred, pubkeyfile, seckeyfile, GNUTLS_OPENPGP_FMT_BASE64);
311
if (ret != GNUTLS_E_SUCCESS) {
313
(stderr, "Error[%d] while reading the OpenPGP key pair ('%s',"
315
ret, pubkeyfile, seckeyfile);
316
fprintf(stdout, "The Error is: %s\n",
317
safer_gnutls_strerror(ret));
321
//GnuTLS server initialization
322
if ((ret = gnutls_dh_params_init(dh_params))
323
!= GNUTLS_E_SUCCESS) {
324
fprintf (stderr, "Error in dh parameter initialization: %s\n",
325
safer_gnutls_strerror(ret));
329
if ((ret = gnutls_dh_params_generate2(*dh_params, mc->dh_bits))
330
!= GNUTLS_E_SUCCESS) {
331
fprintf (stderr, "Error in prime generation: %s\n",
332
safer_gnutls_strerror(ret));
336
gnutls_certificate_set_dh_params(mc->cred, *dh_params);
338
// GnuTLS session creation
339
if ((ret = gnutls_init(session, GNUTLS_SERVER))
340
!= GNUTLS_E_SUCCESS){
341
fprintf(stderr, "Error in GnuTLS session initialization: %s\n",
342
safer_gnutls_strerror(ret));
345
if ((ret = gnutls_priority_set_direct(*session, mc->priority, &err))
346
!= GNUTLS_E_SUCCESS) {
347
fprintf(stderr, "Syntax error at: %s\n", err);
348
fprintf(stderr, "GnuTLS error: %s\n",
349
safer_gnutls_strerror(ret));
353
if ((ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,
355
!= GNUTLS_E_SUCCESS) {
356
fprintf(stderr, "Error setting a credentials set: %s\n",
357
safer_gnutls_strerror(ret));
611
361
/* ignore client certificate if any. */
612
gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);
362
gnutls_certificate_server_set_request (*session,
614
gnutls_dh_set_prime_bits(*session, mc->dh_bits);
365
gnutls_dh_set_prime_bits (*session, mc->dh_bits);
619
/* Avahi log function callback */
620
370
static void empty_log(__attribute__((unused)) AvahiLogLevel level,
621
371
__attribute__((unused)) const char *txt){}
623
/* Called when a Mandos server is found */
624
static int start_mandos_communication(const char *ip, in_port_t port,
373
static int start_mandos_communication(const char *ip, uint16_t port,
625
374
AvahiIfIndex if_index,
626
int af, mandos_context *mc){
627
int ret, tcp_sd = -1;
630
struct sockaddr_in in;
631
struct sockaddr_in6 in6;
377
struct sockaddr_in6 to;
633
378
char *buffer = NULL;
634
char *decrypted_buffer = NULL;
379
char *decrypted_buffer;
635
380
size_t buffer_length = 0;
636
381
size_t buffer_capacity = 0;
382
ssize_t decrypted_buffer_size;
385
char interface[IF_NAMESIZE];
639
386
gnutls_session_t session;
640
int pf; /* Protocol family */
657
fprintf_plus(stderr, "Bad address family: %d\n", af);
662
/* If the interface is specified and we have a list of interfaces */
663
if(if_index != AVAHI_IF_UNSPEC and mc->interfaces != NULL){
664
/* Check if the interface is one of the interfaces we are using */
667
char *interface = NULL;
668
while((interface=argz_next(mc->interfaces, mc->interfaces_size,
670
if(if_nametoindex(interface) == (unsigned int)if_index){
677
/* This interface does not match any in the list, so we don't
678
connect to the server */
680
char interface[IF_NAMESIZE];
681
if(if_indextoname((unsigned int)if_index, interface) == NULL){
682
perror_plus("if_indextoname");
684
fprintf_plus(stderr, "Skipping server on non-used interface"
686
if_indextoname((unsigned int)if_index,
387
gnutls_dh_params_t dh_params;
390
fprintf(stderr, "Setting up a tcp connection to %s, port %d\n",
394
tcp_sd = socket(PF_INET6, SOCK_STREAM, 0);
401
if(if_indextoname((unsigned int)if_index, interface) == NULL){
402
perror("if_indextoname");
405
fprintf(stderr, "Binding to interface %s\n", interface);
694
ret = init_gnutls_session(&session, mc);
408
memset(&to,0,sizeof(to)); /* Spurious warning */
409
to.sin6_family = AF_INET6;
410
ret = inet_pton(AF_INET6, ip, &to.sin6_addr);
700
fprintf_plus(stderr, "Setting up a TCP connection to %s, port %"
701
PRIuMAX "\n", ip, (uintmax_t)port);
704
tcp_sd = socket(pf, SOCK_STREAM, 0);
707
perror_plus("socket");
717
memset(&to, 0, sizeof(to));
719
to.in6.sin6_family = (sa_family_t)af;
720
ret = inet_pton(af, ip, &to.in6.sin6_addr);
722
to.in.sin_family = (sa_family_t)af;
723
ret = inet_pton(af, ip, &to.in.sin_addr);
727
perror_plus("inet_pton");
733
fprintf_plus(stderr, "Bad address: %s\n", ip);
738
to.in6.sin6_port = htons(port);
740
#pragma GCC diagnostic push
741
#pragma GCC diagnostic ignored "-Wstrict-aliasing"
743
if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */
744
(&to.in6.sin6_addr)){ /* -Wstrict-aliasing=2 or lower */
746
#pragma GCC diagnostic pop
748
if(if_index == AVAHI_IF_UNSPEC){
749
fprintf_plus(stderr, "An IPv6 link-local address is"
750
" incomplete without a network interface\n");
754
/* Set the network interface number as scope */
755
to.in6.sin6_scope_id = (uint32_t)if_index;
758
to.in.sin_port = htons(port);
416
fprintf(stderr, "Bad address: %s\n", ip);
419
to.sin6_port = htons(port); /* Spurious warning */
421
to.sin6_scope_id = (uint32_t)if_index;
767
if(af == AF_INET6 and if_index != AVAHI_IF_UNSPEC){
768
char interface[IF_NAMESIZE];
769
if(if_indextoname((unsigned int)if_index, interface) == NULL){
770
perror_plus("if_indextoname");
772
fprintf_plus(stderr, "Connection to: %s%%%s, port %" PRIuMAX
773
"\n", ip, interface, (uintmax_t)port);
776
fprintf_plus(stderr, "Connection to: %s, port %" PRIuMAX "\n",
777
ip, (uintmax_t)port);
779
char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?
780
INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";
783
pcret = inet_ntop(af, &(to.in6.sin6_addr), addrstr,
786
pcret = inet_ntop(af, &(to.in.sin_addr), addrstr,
790
perror_plus("inet_ntop");
424
fprintf(stderr, "Connection to: %s, port %d\n", ip, port);
425
char addrstr[INET6_ADDRSTRLEN] = "";
426
if(inet_ntop(to.sin6_family, &(to.sin6_addr), addrstr,
427
sizeof(addrstr)) == NULL){
792
430
if(strcmp(addrstr, ip) != 0){
793
fprintf_plus(stderr, "Canonical address form: %s\n", addrstr);
804
ret = connect(tcp_sd, &to.in6, sizeof(to));
806
ret = connect(tcp_sd, &to.in, sizeof(to)); /* IPv4 */
809
if ((errno != ECONNREFUSED and errno != ENETUNREACH) or debug){
811
perror_plus("connect");
822
const char *out = mandos_protocol_version;
825
size_t out_size = strlen(out);
826
ret = (int)TEMP_FAILURE_RETRY(write(tcp_sd, out + written,
827
out_size - written));
830
perror_plus("write");
834
written += (size_t)ret;
835
if(written < out_size){
838
if(out == mandos_protocol_version){
431
fprintf(stderr, "Canonical address form: %s\n", addrstr);
436
ret = connect(tcp_sd, (struct sockaddr *) &to, sizeof(to));
442
ret = initgnutls (mc, &session, &dh_params);
448
gnutls_transport_set_ptr (session, (gnutls_transport_ptr_t) tcp_sd);
853
fprintf_plus(stderr, "Establishing TLS session with %s\n", ip);
861
/* This casting via intptr_t is to eliminate warning about casting
862
an int to a pointer type. This is exactly how the GnuTLS Guile
863
function "set-session-transport-fd!" does it. */
864
gnutls_transport_set_ptr(session,
865
(gnutls_transport_ptr_t)(intptr_t)tcp_sd);
873
ret = gnutls_handshake(session);
878
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
880
if(ret != GNUTLS_E_SUCCESS){
451
fprintf(stderr, "Establishing TLS session with %s\n", ip);
454
ret = gnutls_handshake (session);
456
if (ret != GNUTLS_E_SUCCESS){
882
fprintf_plus(stderr, "*** GnuTLS Handshake failed ***\n");
458
fprintf(stderr, "\n*** Handshake failed ***\n");
889
/* Read OpenPGP packet that contains the wanted password */
465
//Retrieve OpenPGP packet that contains the wanted password
892
fprintf_plus(stderr, "Retrieving OpenPGP encrypted password from"
468
fprintf(stderr, "Retrieving pgp encrypted password from %s\n",
903
buffer_capacity = incbuffer(&buffer, buffer_length,
905
if(buffer_capacity == 0){
907
perror_plus("incbuffer");
917
sret = gnutls_record_recv(session, buffer+buffer_length,
473
if (buffer_length + BUFFER_SIZE > buffer_capacity){
474
buffer = realloc(buffer, buffer_capacity + BUFFER_SIZE);
479
buffer_capacity += BUFFER_SIZE;
482
ret = gnutls_record_recv(session, buffer+buffer_length,
924
489
case GNUTLS_E_INTERRUPTED:
925
490
case GNUTLS_E_AGAIN:
927
492
case GNUTLS_E_REHANDSHAKE:
929
ret = gnutls_handshake(session);
935
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
937
fprintf_plus(stderr, "*** GnuTLS Re-handshake failed "
493
ret = gnutls_handshake (session);
495
fprintf(stderr, "\n*** Handshake failed ***\n");
945
fprintf_plus(stderr, "Unknown error while reading data from"
946
" encrypted session with Mandos server\n");
947
gnutls_bye(session, GNUTLS_SHUT_RDWR);
502
fprintf(stderr, "Unknown error while reading data from"
503
" encrypted session with mandos server\n");
505
gnutls_bye (session, GNUTLS_SHUT_RDWR);
952
buffer_length += (size_t) sret;
957
fprintf_plus(stderr, "Closing TLS session\n");
966
ret = gnutls_bye(session, GNUTLS_SHUT_RDWR);
971
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
973
if(buffer_length > 0){
974
ssize_t decrypted_buffer_size;
975
decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,
976
&decrypted_buffer, mc);
977
if(decrypted_buffer_size >= 0){
509
buffer_length += (size_t) ret;
513
if (buffer_length > 0){
514
decrypted_buffer_size = pgp_packet_decrypt(buffer,
518
if (decrypted_buffer_size >= 0){
980
519
while(written < (size_t) decrypted_buffer_size){
986
ret = (int)fwrite(decrypted_buffer + written, 1,
987
(size_t)decrypted_buffer_size - written,
520
ret = (int)fwrite (decrypted_buffer + written, 1,
521
(size_t)decrypted_buffer_size - written,
989
523
if(ret == 0 and ferror(stdout)){
992
fprintf_plus(stderr, "Error writing encrypted data: %s\n",
525
fprintf(stderr, "Error writing encrypted data: %s\n",
998
531
written += (size_t)ret;
1004
/* Shutdown procedure */
1009
free(decrypted_buffer);
1012
ret = (int)TEMP_FAILURE_RETRY(close(tcp_sd));
1018
perror_plus("close");
1020
gnutls_deinit(session);
533
free(decrypted_buffer);
542
fprintf(stderr, "Closing TLS session\n");
546
gnutls_bye (session, GNUTLS_SHUT_RDWR);
549
gnutls_deinit (session);
550
gnutls_certificate_free_credentials (mc->cred);
551
gnutls_global_deinit ();
1030
555
static void resolve_callback(AvahiSServiceResolver *r,
1031
556
AvahiIfIndex interface,
1032
AvahiProtocol proto,
557
AVAHI_GCC_UNUSED AvahiProtocol protocol,
1033
558
AvahiResolverEvent event,
1034
559
const char *name,
1035
560
const char *type,
1143
642
case AVAHI_BROWSER_ALL_FOR_NOW:
1144
643
case AVAHI_BROWSER_CACHE_EXHAUSTED:
1146
fprintf_plus(stderr, "No Mandos server found, still"
1153
/* Signal handler that stops main loop after SIGTERM */
1154
static void handle_sigterm(int sig){
1159
signal_received = sig;
1160
int old_errno = errno;
1161
/* set main loop to exit */
1162
if(simple_poll != NULL){
1163
avahi_simple_poll_quit(simple_poll);
1168
bool get_flags(const char *ifname, struct ifreq *ifr){
1172
int s = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1175
perror_plus("socket");
1179
strcpy(ifr->ifr_name, ifname);
1180
ret = ioctl(s, SIOCGIFFLAGS, ifr);
1184
perror_plus("ioctl SIOCGIFFLAGS");
1192
bool good_flags(const char *ifname, const struct ifreq *ifr){
1194
/* Reject the loopback device */
1195
if(ifr->ifr_flags & IFF_LOOPBACK){
1197
fprintf_plus(stderr, "Rejecting loopback interface \"%s\"\n",
1202
/* Accept point-to-point devices only if connect_to is specified */
1203
if(connect_to != NULL and (ifr->ifr_flags & IFF_POINTOPOINT)){
1205
fprintf_plus(stderr, "Accepting point-to-point interface"
1206
" \"%s\"\n", ifname);
1210
/* Otherwise, reject non-broadcast-capable devices */
1211
if(not (ifr->ifr_flags & IFF_BROADCAST)){
1213
fprintf_plus(stderr, "Rejecting non-broadcast interface"
1214
" \"%s\"\n", ifname);
1218
/* Reject non-ARP interfaces (including dummy interfaces) */
1219
if(ifr->ifr_flags & IFF_NOARP){
1221
fprintf_plus(stderr, "Rejecting non-ARP interface \"%s\"\n",
1227
/* Accept this device */
1229
fprintf_plus(stderr, "Interface \"%s\" is good\n", ifname);
1235
* This function determines if a directory entry in /sys/class/net
1236
* corresponds to an acceptable network device.
1237
* (This function is passed to scandir(3) as a filter function.)
1239
int good_interface(const struct dirent *if_entry){
1240
if(if_entry->d_name[0] == '.'){
1245
if(not get_flags(if_entry->d_name, &ifr)){
1247
fprintf_plus(stderr, "Failed to get flags for interface "
1248
"\"%s\"\n", if_entry->d_name);
1253
if(not good_flags(if_entry->d_name, &ifr)){
1260
* This function determines if a network interface is up.
1262
bool interface_is_up(const char *interface){
1264
if(not get_flags(interface, &ifr)){
1266
fprintf_plus(stderr, "Failed to get flags for interface "
1267
"\"%s\"\n", interface);
1272
return (bool)(ifr.ifr_flags & IFF_UP);
1276
* This function determines if a network interface is running
1278
bool interface_is_running(const char *interface){
1280
if(not get_flags(interface, &ifr)){
1282
fprintf_plus(stderr, "Failed to get flags for interface "
1283
"\"%s\"\n", interface);
1288
return (bool)(ifr.ifr_flags & IFF_RUNNING);
1291
int notdotentries(const struct dirent *direntry){
1292
/* Skip "." and ".." */
1293
if(direntry->d_name[0] == '.'
1294
and (direntry->d_name[1] == '\0'
1295
or (direntry->d_name[1] == '.'
1296
and direntry->d_name[2] == '\0'))){
1302
/* Is this directory entry a runnable program? */
1303
int runnable_hook(const struct dirent *direntry){
1308
if((direntry->d_name)[0] == '\0'){
1313
sret = strspn(direntry->d_name, "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
1314
"abcdefghijklmnopqrstuvwxyz"
1317
if((direntry->d_name)[sret] != '\0'){
1318
/* Contains non-allowed characters */
1320
fprintf_plus(stderr, "Ignoring hook \"%s\" with bad name\n",
1326
char *fullname = NULL;
1327
ret = asprintf(&fullname, "%s/%s", hookdir, direntry->d_name);
1329
perror_plus("asprintf");
1333
ret = stat(fullname, &st);
1336
perror_plus("Could not stat hook");
1340
if(not (S_ISREG(st.st_mode))){
1341
/* Not a regular file */
1343
fprintf_plus(stderr, "Ignoring hook \"%s\" - not a file\n",
1348
if(not (st.st_mode & (S_IXUSR | S_IXGRP | S_IXOTH))){
1349
/* Not executable */
1351
fprintf_plus(stderr, "Ignoring hook \"%s\" - not executable\n",
1357
fprintf_plus(stderr, "Hook \"%s\" is acceptable\n",
1363
int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,
1364
mandos_context *mc){
1366
struct timespec now;
1367
struct timespec waited_time;
1368
intmax_t block_time;
1371
if(mc->current_server == NULL){
1373
fprintf_plus(stderr, "Wait until first server is found."
1376
ret = avahi_simple_poll_iterate(s, -1);
1379
fprintf_plus(stderr, "Check current_server if we should run"
1382
/* the current time */
1383
ret = clock_gettime(CLOCK_MONOTONIC, &now);
648
/* Combines file name and path and returns the malloced new
649
string. some sane checks could/should be added */
650
static const char *combinepath(const char *first, const char *second){
651
size_t f_len = strlen(first);
652
size_t s_len = strlen(second);
653
char *tmp = malloc(f_len + s_len + 2);
658
memcpy(tmp, first, f_len); /* Spurious warning */
662
memcpy(tmp + f_len + 1, second, s_len); /* Spurious warning */
664
tmp[f_len + 1 + s_len] = '\0';
669
int main(AVAHI_GCC_UNUSED int argc, AVAHI_GCC_UNUSED char*argv[]) {
670
AvahiServerConfig config;
671
AvahiSServiceBrowser *sb = NULL;
675
int returncode = EXIT_SUCCESS;
676
const char *interface = "eth0";
677
struct ifreq network;
679
char *connect_to = NULL;
680
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
681
mandos_context mc = { .simple_poll = NULL, .server = NULL,
682
.dh_bits = 1024, .priority = "SECURE256"};
684
debug_int = debug ? 1 : 0;
686
struct option long_options[] = {
687
{"debug", no_argument, &debug_int, 1},
688
{"connect", required_argument, NULL, 'c'},
689
{"interface", required_argument, NULL, 'i'},
690
{"keydir", required_argument, NULL, 'd'},
691
{"seckey", required_argument, NULL, 's'},
692
{"pubkey", required_argument, NULL, 'p'},
693
{"dh-bits", required_argument, NULL, 'D'},
694
{"priority", required_argument, NULL, 'P'},
697
int option_index = 0;
698
ret = getopt_long (argc, argv, "i:", long_options,
725
mc.dh_bits = (unsigned int) strtol(optarg, NULL, 10);
732
mc.priority = optarg;
739
debug = debug_int ? true : false;
741
pubkeyfile = combinepath(keydir, pubkeyfile);
742
if (pubkeyfile == NULL){
743
perror("combinepath");
744
returncode = EXIT_FAILURE;
748
seckeyfile = combinepath(keydir, seckeyfile);
749
if (seckeyfile == NULL){
750
perror("combinepath");
754
if_index = (AvahiIfIndex) if_nametoindex(interface);
756
fprintf(stderr, "No such interface: \"%s\"\n", interface);
760
if(connect_to != NULL){
761
/* Connect directly, do not use Zeroconf */
762
/* (Mainly meant for debugging) */
763
char *address = strrchr(connect_to, ':');
765
fprintf(stderr, "No colon in address\n");
769
uint16_t port = (uint16_t) strtol(address+1, NULL, 10);
771
perror("Bad port number");
775
address = connect_to;
776
ret = start_mandos_communication(address, port, if_index, &mc);
784
sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
787
returncode = EXIT_FAILURE;
790
strcpy(network.ifr_name, interface); /* Spurious warning */
791
ret = ioctl(sd, SIOCGIFFLAGS, &network);
794
perror("ioctl SIOCGIFFLAGS");
795
returncode = EXIT_FAILURE;
798
if((network.ifr_flags & IFF_UP) == 0){
799
network.ifr_flags |= IFF_UP;
800
ret = ioctl(sd, SIOCSIFFLAGS, &network);
1385
perror_plus("clock_gettime");
1388
/* Calculating in ms how long time between now and server
1389
who we visted longest time ago. Now - last seen. */
1390
waited_time.tv_sec = (now.tv_sec
1391
- mc->current_server->last_seen.tv_sec);
1392
waited_time.tv_nsec = (now.tv_nsec
1393
- mc->current_server->last_seen.tv_nsec);
1394
/* total time is 10s/10,000ms.
1395
Converting to s from ms by dividing by 1,000,
1396
and ns to ms by dividing by 1,000,000. */
1397
block_time = ((retry_interval
1398
- ((intmax_t)waited_time.tv_sec * 1000))
1399
- ((intmax_t)waited_time.tv_nsec / 1000000));
1402
fprintf_plus(stderr, "Blocking for %" PRIdMAX " ms\n",
1406
if(block_time <= 0){
1407
ret = start_mandos_communication(mc->current_server->ip,
1408
mc->current_server->port,
1409
mc->current_server->if_index,
1410
mc->current_server->af, mc);
1412
avahi_simple_poll_quit(s);
1415
ret = clock_gettime(CLOCK_MONOTONIC,
1416
&mc->current_server->last_seen);
1418
perror_plus("clock_gettime");
1421
mc->current_server = mc->current_server->next;
1422
block_time = 0; /* Call avahi to find new Mandos
1423
servers, but don't block */
1426
ret = avahi_simple_poll_iterate(s, (int)block_time);
1429
if (ret > 0 or errno != EINTR){
1430
return (ret != 1) ? ret : 0;
1436
/* Set effective uid to 0, return errno */
1437
error_t raise_privileges(void){
1438
error_t old_errno = errno;
1439
error_t ret_errno = 0;
1440
if(seteuid(0) == -1){
1442
perror_plus("seteuid");
1448
/* Set effective and real user ID to 0. Return errno. */
1449
error_t raise_privileges_permanently(void){
1450
error_t old_errno = errno;
1451
error_t ret_errno = raise_privileges();
1456
if(setuid(0) == -1){
1458
perror_plus("seteuid");
1464
/* Set effective user ID to unprivileged saved user ID */
1465
error_t lower_privileges(void){
1466
error_t old_errno = errno;
1467
error_t ret_errno = 0;
1468
if(seteuid(uid) == -1){
1470
perror_plus("seteuid");
1476
/* Lower privileges permanently */
1477
error_t lower_privileges_permanently(void){
1478
error_t old_errno = errno;
1479
error_t ret_errno = 0;
1480
if(setuid(uid) == -1){
1482
perror_plus("setuid");
1488
bool run_network_hooks(const char *mode, const char *interface,
1490
struct dirent **direntries;
1491
struct dirent *direntry;
1493
int numhooks = scandir(hookdir, &direntries, runnable_hook,
1496
if(errno == ENOENT){
1498
fprintf_plus(stderr, "Network hook directory \"%s\" not"
1499
" found\n", hookdir);
1502
perror_plus("scandir");
1505
int devnull = open("/dev/null", O_RDONLY);
1506
for(int i = 0; i < numhooks; i++){
1507
direntry = direntries[i];
1508
char *fullname = NULL;
1509
ret = asprintf(&fullname, "%s/%s", hookdir, direntry->d_name);
1511
perror_plus("asprintf");
1515
fprintf_plus(stderr, "Running network hook \"%s\"\n",
1518
pid_t hook_pid = fork();
1521
/* Raise privileges */
1522
raise_privileges_permanently();
1527
perror_plus("setgid");
1529
/* Reset supplementary groups */
1531
ret = setgroups(0, NULL);
1533
perror_plus("setgroups");
1535
dup2(devnull, STDIN_FILENO);
1537
dup2(STDERR_FILENO, STDOUT_FILENO);
1538
ret = setenv("MANDOSNETHOOKDIR", hookdir, 1);
1540
perror_plus("setenv");
1543
ret = setenv("DEVICE", interface, 1);
1545
perror_plus("setenv");
1548
ret = setenv("VERBOSITY", debug ? "1" : "0", 1);
1550
perror_plus("setenv");
1553
ret = setenv("MODE", mode, 1);
1555
perror_plus("setenv");
1559
ret = asprintf(&delaystring, "%f", delay);
1561
perror_plus("asprintf");
1564
ret = setenv("DELAY", delaystring, 1);
1567
perror_plus("setenv");
1571
if(connect_to != NULL){
1572
ret = setenv("CONNECT", connect_to, 1);
1574
perror_plus("setenv");
1578
if(execl(fullname, direntry->d_name, mode, NULL) == -1){
1579
perror_plus("execl");
1580
_exit(EXIT_FAILURE);
1584
if(TEMP_FAILURE_RETRY(waitpid(hook_pid, &status, 0)) == -1){
1585
perror_plus("waitpid");
1589
if(WIFEXITED(status)){
1590
if(WEXITSTATUS(status) != 0){
1591
fprintf_plus(stderr, "Warning: network hook \"%s\" exited"
1592
" with status %d\n", direntry->d_name,
1593
WEXITSTATUS(status));
1597
} else if(WIFSIGNALED(status)){
1598
fprintf_plus(stderr, "Warning: network hook \"%s\" died by"
1599
" signal %d\n", direntry->d_name,
1604
fprintf_plus(stderr, "Warning: network hook \"%s\""
1605
" crashed\n", direntry->d_name);
1612
fprintf_plus(stderr, "Network hook \"%s\" ran successfully\n",
1621
error_t bring_up_interface(const char *const interface,
1624
error_t old_errno = errno;
1625
error_t ret_errno = 0;
1626
int ret, ret_setflags;
1627
struct ifreq network;
1628
unsigned int if_index = if_nametoindex(interface);
1630
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
1640
if(not interface_is_up(interface)){
1641
if(not get_flags(interface, &network) and debug){
1643
fprintf_plus(stderr, "Failed to get flags for interface "
1644
"\"%s\"\n", interface);
1647
network.ifr_flags |= IFF_UP;
1649
sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1652
perror_plus("socket");
1664
fprintf_plus(stderr, "Bringing up interface \"%s\"\n",
1668
/* Raise priviliges */
1672
/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO
1673
messages about the network interface to mess up the prompt */
1674
int ret_linux = klogctl(8, NULL, 5);
1675
bool restore_loglevel = true;
1676
if(ret_linux == -1){
1677
restore_loglevel = false;
1678
perror_plus("klogctl");
1680
#endif /* __linux__ */
1681
ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
1684
if(restore_loglevel){
1685
ret_linux = klogctl(7, NULL, 0);
1686
if(ret_linux == -1){
1687
perror_plus("klogctl");
1690
#endif /* __linux__ */
1692
/* Lower privileges */
1695
/* Close the socket */
1696
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1698
perror_plus("close");
1701
if(ret_setflags == -1){
1703
perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");
1708
fprintf_plus(stderr, "Interface \"%s\" is already up; good\n",
1712
/* Sleep checking until interface is running.
1713
Check every 0.25s, up to total time of delay */
1714
for(int i=0; i < delay * 4; i++){
1715
if(interface_is_running(interface)){
1718
struct timespec sleeptime = { .tv_nsec = 250000000 };
1719
ret = nanosleep(&sleeptime, NULL);
1720
if(ret == -1 and errno != EINTR){
1721
perror_plus("nanosleep");
1729
error_t take_down_interface(const char *const interface){
1731
error_t old_errno = errno;
1732
error_t ret_errno = 0;
1733
int ret, ret_setflags;
1734
struct ifreq network;
1735
unsigned int if_index = if_nametoindex(interface);
1737
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
1741
if(interface_is_up(interface)){
1742
if(not get_flags(interface, &network) and debug){
1744
fprintf_plus(stderr, "Failed to get flags for interface "
1745
"\"%s\"\n", interface);
1748
network.ifr_flags &= ~(short)IFF_UP; /* clear flag */
1750
sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1753
perror_plus("socket");
1759
fprintf_plus(stderr, "Taking down interface \"%s\"\n",
1763
/* Raise priviliges */
1766
ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
1769
/* Lower privileges */
1772
/* Close the socket */
1773
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1775
perror_plus("close");
1778
if(ret_setflags == -1){
1780
perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");
1785
fprintf_plus(stderr, "Interface \"%s\" is already down; odd\n",
1793
int main(int argc, char *argv[]){
1794
mandos_context mc = { .server = NULL, .dh_bits = 1024,
1795
.priority = "SECURE256:!CTYPE-X.509:"
1796
"+CTYPE-OPENPGP", .current_server = NULL,
1797
.interfaces = NULL, .interfaces_size = 0 };
1798
AvahiSServiceBrowser *sb = NULL;
1803
int exitcode = EXIT_SUCCESS;
1804
char *interfaces_to_take_down = NULL;
1805
size_t interfaces_to_take_down_size = 0;
1806
char tempdir[] = "/tmp/mandosXXXXXX";
1807
bool tempdir_created = false;
1808
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
1809
const char *seckey = PATHDIR "/" SECKEY;
1810
const char *pubkey = PATHDIR "/" PUBKEY;
1811
char *interfaces_hooks = NULL;
1812
size_t interfaces_hooks_size = 0;
1814
bool gnutls_initialized = false;
1815
bool gpgme_initialized = false;
1817
double retry_interval = 10; /* 10s between trying a server and
1818
retrying the same server again */
1820
struct sigaction old_sigterm_action = { .sa_handler = SIG_DFL };
1821
struct sigaction sigterm_action = { .sa_handler = handle_sigterm };
1826
/* Lower any group privileges we might have, just to be safe */
1830
perror_plus("setgid");
1833
/* Lower user privileges (temporarily) */
1837
perror_plus("seteuid");
1845
struct argp_option options[] = {
1846
{ .name = "debug", .key = 128,
1847
.doc = "Debug mode", .group = 3 },
1848
{ .name = "connect", .key = 'c',
1849
.arg = "ADDRESS:PORT",
1850
.doc = "Connect directly to a specific Mandos server",
1852
{ .name = "interface", .key = 'i',
1854
.doc = "Network interface that will be used to search for"
1857
{ .name = "seckey", .key = 's',
1859
.doc = "OpenPGP secret key file base name",
1861
{ .name = "pubkey", .key = 'p',
1863
.doc = "OpenPGP public key file base name",
1865
{ .name = "dh-bits", .key = 129,
1867
.doc = "Bit length of the prime number used in the"
1868
" Diffie-Hellman key exchange",
1870
{ .name = "priority", .key = 130,
1872
.doc = "GnuTLS priority string for the TLS handshake",
1874
{ .name = "delay", .key = 131,
1876
.doc = "Maximum delay to wait for interface startup",
1878
{ .name = "retry", .key = 132,
1880
.doc = "Retry interval used when denied by the Mandos server",
1882
{ .name = "network-hook-dir", .key = 133,
1884
.doc = "Directory where network hooks are located",
1887
* These reproduce what we would get without ARGP_NO_HELP
1889
{ .name = "help", .key = '?',
1890
.doc = "Give this help list", .group = -1 },
1891
{ .name = "usage", .key = -3,
1892
.doc = "Give a short usage message", .group = -1 },
1893
{ .name = "version", .key = 'V',
1894
.doc = "Print program version", .group = -1 },
1898
error_t parse_opt(int key, char *arg,
1899
struct argp_state *state){
1902
case 128: /* --debug */
1905
case 'c': /* --connect */
1908
case 'i': /* --interface */
1909
ret_errno = argz_add_sep(&mc.interfaces, &mc.interfaces_size,
1912
argp_error(state, "%s", strerror(ret_errno));
1915
case 's': /* --seckey */
1918
case 'p': /* --pubkey */
1921
case 129: /* --dh-bits */
1923
tmpmax = strtoimax(arg, &tmp, 10);
1924
if(errno != 0 or tmp == arg or *tmp != '\0'
1925
or tmpmax != (typeof(mc.dh_bits))tmpmax){
1926
argp_error(state, "Bad number of DH bits");
1928
mc.dh_bits = (typeof(mc.dh_bits))tmpmax;
1930
case 130: /* --priority */
1933
case 131: /* --delay */
1935
delay = strtof(arg, &tmp);
1936
if(errno != 0 or tmp == arg or *tmp != '\0'){
1937
argp_error(state, "Bad delay");
1939
case 132: /* --retry */
1941
retry_interval = strtod(arg, &tmp);
1942
if(errno != 0 or tmp == arg or *tmp != '\0'
1943
or (retry_interval * 1000) > INT_MAX
1944
or retry_interval < 0){
1945
argp_error(state, "Bad retry interval");
1948
case 133: /* --network-hook-dir */
1952
* These reproduce what we would get without ARGP_NO_HELP
1954
case '?': /* --help */
1955
argp_state_help(state, state->out_stream,
1956
(ARGP_HELP_STD_HELP | ARGP_HELP_EXIT_ERR)
1957
& ~(unsigned int)ARGP_HELP_EXIT_OK);
1958
case -3: /* --usage */
1959
argp_state_help(state, state->out_stream,
1960
ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);
1961
case 'V': /* --version */
1962
fprintf_plus(state->out_stream, "%s\n", argp_program_version);
1963
exit(argp_err_exit_status);
1966
return ARGP_ERR_UNKNOWN;
1971
struct argp argp = { .options = options, .parser = parse_opt,
1973
.doc = "Mandos client -- Get and decrypt"
1974
" passwords from a Mandos server" };
1975
ret = argp_parse(&argp, argc, argv,
1976
ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);
1983
perror_plus("argp_parse");
1984
exitcode = EX_OSERR;
1987
exitcode = EX_USAGE;
1993
/* Work around Debian bug #633582:
1994
<http://bugs.debian.org/633582> */
1996
/* Re-raise priviliges */
1997
if(raise_privileges() == 0){
2000
if(strcmp(seckey, PATHDIR "/" SECKEY) == 0){
2001
int seckey_fd = open(seckey, O_RDONLY);
2002
if(seckey_fd == -1){
2003
perror_plus("open");
2005
ret = (int)TEMP_FAILURE_RETRY(fstat(seckey_fd, &st));
2007
perror_plus("fstat");
2009
if(S_ISREG(st.st_mode)
2010
and st.st_uid == 0 and st.st_gid == 0){
2011
ret = fchown(seckey_fd, uid, gid);
2013
perror_plus("fchown");
2017
TEMP_FAILURE_RETRY(close(seckey_fd));
2021
if(strcmp(pubkey, PATHDIR "/" PUBKEY) == 0){
2022
int pubkey_fd = open(pubkey, O_RDONLY);
2023
if(pubkey_fd == -1){
2024
perror_plus("open");
2026
ret = (int)TEMP_FAILURE_RETRY(fstat(pubkey_fd, &st));
2028
perror_plus("fstat");
2030
if(S_ISREG(st.st_mode)
2031
and st.st_uid == 0 and st.st_gid == 0){
2032
ret = fchown(pubkey_fd, uid, gid);
2034
perror_plus("fchown");
2038
TEMP_FAILURE_RETRY(close(pubkey_fd));
2042
/* Lower privileges */
2047
/* Remove invalid interface names (except "none") */
2049
char *interface = NULL;
2050
while((interface = argz_next(mc.interfaces, mc.interfaces_size,
2052
if(strcmp(interface, "none") != 0
2053
and if_nametoindex(interface) == 0){
2054
if(interface[0] != '\0'){
2055
fprintf_plus(stderr, "Not using nonexisting interface"
2056
" \"%s\"\n", interface);
2058
argz_delete(&mc.interfaces, &mc.interfaces_size, interface);
2064
/* Run network hooks */
2066
if(mc.interfaces != NULL){
2067
interfaces_hooks = malloc(mc.interfaces_size);
2068
if(interfaces_hooks == NULL){
2069
perror_plus("malloc");
2072
memcpy(interfaces_hooks, mc.interfaces, mc.interfaces_size);
2073
interfaces_hooks_size = mc.interfaces_size;
2074
argz_stringify(interfaces_hooks, interfaces_hooks_size,
2077
if(not run_network_hooks("start", interfaces_hooks != NULL ?
2078
interfaces_hooks : "", delay)){
2084
avahi_set_log_function(empty_log);
2087
/* Initialize Avahi early so avahi_simple_poll_quit() can be called
2088
from the signal handler */
2089
/* Initialize the pseudo-RNG for Avahi */
2090
srand((unsigned int) time(NULL));
2091
simple_poll = avahi_simple_poll_new();
2092
if(simple_poll == NULL){
2093
fprintf_plus(stderr,
2094
"Avahi: Failed to create simple poll object.\n");
2095
exitcode = EX_UNAVAILABLE;
2099
sigemptyset(&sigterm_action.sa_mask);
2100
ret = sigaddset(&sigterm_action.sa_mask, SIGINT);
2102
perror_plus("sigaddset");
2103
exitcode = EX_OSERR;
2106
ret = sigaddset(&sigterm_action.sa_mask, SIGHUP);
2108
perror_plus("sigaddset");
2109
exitcode = EX_OSERR;
2112
ret = sigaddset(&sigterm_action.sa_mask, SIGTERM);
2114
perror_plus("sigaddset");
2115
exitcode = EX_OSERR;
2118
/* Need to check if the handler is SIG_IGN before handling:
2119
| [[info:libc:Initial Signal Actions]] |
2120
| [[info:libc:Basic Signal Handling]] |
2122
ret = sigaction(SIGINT, NULL, &old_sigterm_action);
2124
perror_plus("sigaction");
2127
if(old_sigterm_action.sa_handler != SIG_IGN){
2128
ret = sigaction(SIGINT, &sigterm_action, NULL);
2130
perror_plus("sigaction");
2131
exitcode = EX_OSERR;
2135
ret = sigaction(SIGHUP, NULL, &old_sigterm_action);
2137
perror_plus("sigaction");
2140
if(old_sigterm_action.sa_handler != SIG_IGN){
2141
ret = sigaction(SIGHUP, &sigterm_action, NULL);
2143
perror_plus("sigaction");
2144
exitcode = EX_OSERR;
2148
ret = sigaction(SIGTERM, NULL, &old_sigterm_action);
2150
perror_plus("sigaction");
2153
if(old_sigterm_action.sa_handler != SIG_IGN){
2154
ret = sigaction(SIGTERM, &sigterm_action, NULL);
2156
perror_plus("sigaction");
2157
exitcode = EX_OSERR;
2162
/* If no interfaces were specified, make a list */
2163
if(mc.interfaces == NULL){
2164
struct dirent **direntries;
2165
/* Look for any good interfaces */
2166
ret = scandir(sys_class_net, &direntries, good_interface,
2169
/* Add all found interfaces to interfaces list */
2170
for(int i = 0; i < ret; ++i){
2171
ret_errno = argz_add(&mc.interfaces, &mc.interfaces_size,
2172
direntries[i]->d_name);
2174
perror_plus("argz_add");
2178
fprintf_plus(stderr, "Will use interface \"%s\"\n",
2179
direntries[i]->d_name);
2185
fprintf_plus(stderr, "Could not find a network interface\n");
2186
exitcode = EXIT_FAILURE;
2191
/* Bring up interfaces which are down, and remove any "none"s */
2193
char *interface = NULL;
2194
while((interface = argz_next(mc.interfaces, mc.interfaces_size,
2196
/* If interface name is "none", stop bringing up interfaces.
2197
Also remove all instances of "none" from the list */
2198
if(strcmp(interface, "none") == 0){
2199
argz_delete(&mc.interfaces, &mc.interfaces_size,
2202
while((interface = argz_next(mc.interfaces,
2203
mc.interfaces_size, interface))){
2204
if(strcmp(interface, "none") == 0){
2205
argz_delete(&mc.interfaces, &mc.interfaces_size,
2212
bool interface_was_up = interface_is_up(interface);
2213
ret = bring_up_interface(interface, delay);
2214
if(not interface_was_up){
2217
perror_plus("Failed to bring up interface");
2219
ret_errno = argz_add(&interfaces_to_take_down,
2220
&interfaces_to_take_down_size,
2225
if(debug and (interfaces_to_take_down == NULL)){
2226
fprintf_plus(stderr, "No interfaces were brought up\n");
2230
/* If we only got one interface, explicitly use only that one */
2231
if(argz_count(mc.interfaces, mc.interfaces_size) == 1){
2233
fprintf_plus(stderr, "Using only interface \"%s\"\n",
2236
if_index = (AvahiIfIndex)if_nametoindex(mc.interfaces);
2243
ret = init_gnutls_global(pubkey, seckey, &mc);
2245
fprintf_plus(stderr, "init_gnutls_global failed\n");
2246
exitcode = EX_UNAVAILABLE;
2249
gnutls_initialized = true;
2256
if(mkdtemp(tempdir) == NULL){
2257
perror_plus("mkdtemp");
2260
tempdir_created = true;
2266
if(not init_gpgme(pubkey, seckey, tempdir, &mc)){
2267
fprintf_plus(stderr, "init_gpgme failed\n");
2268
exitcode = EX_UNAVAILABLE;
2271
gpgme_initialized = true;
2278
if(connect_to != NULL){
2279
/* Connect directly, do not use Zeroconf */
2280
/* (Mainly meant for debugging) */
2281
char *address = strrchr(connect_to, ':');
2283
if(address == NULL){
2284
fprintf_plus(stderr, "No colon in address\n");
2285
exitcode = EX_USAGE;
2295
tmpmax = strtoimax(address+1, &tmp, 10);
2296
if(errno != 0 or tmp == address+1 or *tmp != '\0'
2297
or tmpmax != (in_port_t)tmpmax){
2298
fprintf_plus(stderr, "Bad port number\n");
2299
exitcode = EX_USAGE;
2307
port = (in_port_t)tmpmax;
2309
/* Colon in address indicates IPv6 */
2311
if(strchr(connect_to, ':') != NULL){
2313
/* Accept [] around IPv6 address - see RFC 5952 */
2314
if(connect_to[0] == '[' and address[-1] == ']')
2322
address = connect_to;
2328
while(not quit_now){
2329
ret = start_mandos_communication(address, port, if_index, af,
2331
if(quit_now or ret == 0){
2335
fprintf_plus(stderr, "Retrying in %d seconds\n",
2336
(int)retry_interval);
2338
sleep((unsigned int)retry_interval);
2342
exitcode = EXIT_SUCCESS;
2353
AvahiServerConfig config;
2354
/* Do not publish any local Zeroconf records */
802
perror("ioctl SIOCSIFFLAGS");
803
returncode = EXIT_FAILURE;
810
avahi_set_log_function(empty_log);
813
/* Initialize the psuedo-RNG */
814
srand((unsigned int) time(NULL));
816
/* Allocate main loop object */
817
if (!(mc.simple_poll = avahi_simple_poll_new())) {
818
fprintf(stderr, "Failed to create simple poll object.\n");
819
returncode = EXIT_FAILURE;
823
/* Do not publish any local records */
2355
824
avahi_server_config_init(&config);
2356
825
config.publish_hinfo = 0;
2357
826
config.publish_addresses = 0;
2358
827
config.publish_workstation = 0;
2359
828
config.publish_domain = 0;
2361
830
/* Allocate a new server */
2362
mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),
2363
&config, NULL, NULL, &ret_errno);
831
mc.server=avahi_server_new(avahi_simple_poll_get(mc.simple_poll),
832
&config, NULL, NULL, &error);
2365
/* Free the Avahi configuration data */
834
/* Free the configuration data */
2366
835
avahi_server_config_free(&config);
2369
/* Check if creating the Avahi server object succeeded */
2370
if(mc.server == NULL){
2371
fprintf_plus(stderr, "Failed to create Avahi server: %s\n",
2372
avahi_strerror(ret_errno));
2373
exitcode = EX_UNAVAILABLE;
2381
/* Create the Avahi service browser */
2382
sb = avahi_s_service_browser_new(mc.server, if_index,
2383
AVAHI_PROTO_UNSPEC, "_mandos._tcp",
2384
NULL, 0, browse_callback,
2387
fprintf_plus(stderr, "Failed to create service browser: %s\n",
2388
avahi_strerror(avahi_server_errno(mc.server)));
2389
exitcode = EX_UNAVAILABLE;
2397
/* Run the main loop */
2400
fprintf_plus(stderr, "Starting Avahi loop search\n");
2403
ret = avahi_loop_with_timeout(simple_poll,
2404
(int)(retry_interval * 1000), &mc);
2406
fprintf_plus(stderr, "avahi_loop_with_timeout exited %s\n",
2407
(ret == 0) ? "successfully" : "with error");
2413
fprintf_plus(stderr, "%s exiting\n", argv[0]);
2416
/* Cleanup things */
2417
free(mc.interfaces);
2420
avahi_s_service_browser_free(sb);
2422
if(mc.server != NULL)
2423
avahi_server_free(mc.server);
2425
if(simple_poll != NULL)
2426
avahi_simple_poll_free(simple_poll);
2428
if(gnutls_initialized){
2429
gnutls_certificate_free_credentials(mc.cred);
2430
gnutls_global_deinit();
2431
gnutls_dh_params_deinit(mc.dh_params);
2434
if(gpgme_initialized){
2435
gpgme_release(mc.ctx);
2438
/* Cleans up the circular linked list of Mandos servers the client
2440
if(mc.current_server != NULL){
2441
mc.current_server->prev->next = NULL;
2442
while(mc.current_server != NULL){
2443
server *next = mc.current_server->next;
2444
free(mc.current_server);
2445
mc.current_server = next;
2449
/* Re-raise priviliges */
2453
/* Run network hooks */
2454
run_network_hooks("stop", interfaces_hooks != NULL ?
2455
interfaces_hooks : "", delay);
2457
/* Take down the network interfaces which were brought up */
2459
char *interface = NULL;
2460
while((interface=argz_next(interfaces_to_take_down,
2461
interfaces_to_take_down_size,
2463
ret_errno = take_down_interface(interface);
2466
perror_plus("Failed to take down interface");
2469
if(debug and (interfaces_to_take_down == NULL)){
2470
fprintf_plus(stderr, "No interfaces needed to be taken"
2475
lower_privileges_permanently();
2478
free(interfaces_to_take_down);
2479
free(interfaces_hooks);
2481
/* Removes the GPGME temp directory and all files inside */
2482
if(tempdir_created){
2483
struct dirent **direntries = NULL;
2484
struct dirent *direntry = NULL;
2485
int numentries = scandir(tempdir, &direntries, notdotentries,
2487
if (numentries > 0){
2488
for(int i = 0; i < numentries; i++){
2489
direntry = direntries[i];
2490
char *fullname = NULL;
2491
ret = asprintf(&fullname, "%s/%s", tempdir,
2494
perror_plus("asprintf");
2497
ret = remove(fullname);
2499
fprintf_plus(stderr, "remove(\"%s\"): %s\n", fullname,
2506
/* need to clean even if 0 because man page doesn't specify */
2508
if (numentries == -1){
2509
perror_plus("scandir");
2511
ret = rmdir(tempdir);
2512
if(ret == -1 and errno != ENOENT){
2513
perror_plus("rmdir");
2518
sigemptyset(&old_sigterm_action.sa_mask);
2519
old_sigterm_action.sa_handler = SIG_DFL;
2520
ret = (int)TEMP_FAILURE_RETRY(sigaction(signal_received,
2521
&old_sigterm_action,
2524
perror_plus("sigaction");
2527
ret = raise(signal_received);
2528
} while(ret != 0 and errno == EINTR);
2530
perror_plus("raise");
2533
TEMP_FAILURE_RETRY(pause());
837
/* Check if creating the server object succeeded */
839
fprintf(stderr, "Failed to create server: %s\n",
840
avahi_strerror(error));
841
returncode = EXIT_FAILURE;
845
/* Create the service browser */
846
sb = avahi_s_service_browser_new(mc.server, if_index,
848
"_mandos._tcp", NULL, 0,
849
browse_callback, &mc);
851
fprintf(stderr, "Failed to create service browser: %s\n",
852
avahi_strerror(avahi_server_errno(mc.server)));
853
returncode = EXIT_FAILURE;
857
/* Run the main loop */
860
fprintf(stderr, "Starting avahi loop search\n");
863
avahi_simple_poll_loop(mc.simple_poll);
868
fprintf(stderr, "%s exiting\n", argv[0]);
873
avahi_s_service_browser_free(sb);
876
avahi_server_free(mc.server);
879
avahi_simple_poll_free(mc.simple_poll);