33
104
#include <avahi-common/malloc.h>
34
105
#include <avahi-common/error.h>
37
#include <sys/types.h> /* socket(), setsockopt(), inet_pton() */
38
#include <sys/socket.h> /* socket(), setsockopt(), struct sockaddr_in6, struct in6_addr, inet_pton() */
39
#include <gnutls/gnutls.h> /* ALL GNUTLS STUFF */
40
#include <gnutls/openpgp.h> /* gnutls with openpgp stuff */
42
#include <unistd.h> /* close() */
43
#include <netinet/in.h>
44
#include <stdbool.h> /* true */
45
#include <string.h> /* memset */
46
#include <arpa/inet.h> /* inet_pton() */
47
#include <iso646.h> /* not */
50
#include <errno.h> /* perror() */
55
#define CERT_ROOT "/conf/conf.d/cryptkeyreq/"
57
#define CERTFILE CERT_ROOT "openpgp-client.txt"
58
#define KEYFILE CERT_ROOT "openpgp-client-key.txt"
108
#include <gnutls/gnutls.h> /* All GnuTLS types, constants and
111
init_gnutls_session(),
113
#include <gnutls/openpgp.h>
114
/* gnutls_certificate_set_openpgp_key_file(),
115
GNUTLS_OPENPGP_FMT_BASE64 */
118
#include <gpgme.h> /* All GPGME types, constants and
121
GPGME_PROTOCOL_OpenPGP,
59
124
#define BUFFER_SIZE 256
126
#define PATHDIR "/conf/conf.d/mandos"
127
#define SECKEY "seckey.txt"
128
#define PUBKEY "pubkey.txt"
129
#define HOOKDIR "/lib/mandos/network-hooks.d"
132
static const char mandos_protocol_version[] = "1";
133
const char *argp_program_version = "mandos-client " VERSION;
134
const char *argp_program_bug_address = "<mandos@recompile.se>";
135
static const char sys_class_net[] = "/sys/class/net";
136
char *connect_to = NULL;
137
const char *hookdir = HOOKDIR;
141
/* Doubly linked list that need to be circularly linked when used */
142
typedef struct server{
145
AvahiIfIndex if_index;
147
struct timespec last_seen;
152
/* Used for passing in values through the Avahi callback functions */
65
gnutls_session_t session;
154
AvahiSimplePoll *simple_poll;
66
156
gnutls_certificate_credentials_t cred;
157
unsigned int dh_bits;
67
158
gnutls_dh_params_t dh_params;
71
ssize_t gpg_packet_decrypt (char *packet, size_t packet_size, char **new_packet, char *homedir){
72
gpgme_data_t dh_crypto, dh_plain;
159
const char *priority;
161
server *current_server;
164
/* global context so signal handler can reach it*/
165
mandos_context mc = { .simple_poll = NULL, .server = NULL,
166
.dh_bits = 1024, .priority = "SECURE256"
167
":!CTYPE-X.509:+CTYPE-OPENPGP",
168
.current_server = NULL };
170
sig_atomic_t quit_now = 0;
171
int signal_received = 0;
173
/* Function to use when printing errors */
174
void perror_plus(const char *print_text){
176
fprintf(stderr, "Mandos plugin %s: ",
177
program_invocation_short_name);
182
__attribute__((format (gnu_printf, 2, 3)))
183
int fprintf_plus(FILE *stream, const char *format, ...){
185
va_start (ap, format);
187
TEMP_FAILURE_RETRY(fprintf(stream, "Mandos plugin %s: ",
188
program_invocation_short_name));
189
return TEMP_FAILURE_RETRY(vfprintf(stream, format, ap));
193
* Make additional room in "buffer" for at least BUFFER_SIZE more
194
* bytes. "buffer_capacity" is how much is currently allocated,
195
* "buffer_length" is how much is already used.
197
size_t incbuffer(char **buffer, size_t buffer_length,
198
size_t buffer_capacity){
199
if(buffer_length + BUFFER_SIZE > buffer_capacity){
200
*buffer = realloc(*buffer, buffer_capacity + BUFFER_SIZE);
204
buffer_capacity += BUFFER_SIZE;
206
return buffer_capacity;
209
/* Add server to set of servers to retry periodically */
210
bool add_server(const char *ip, uint16_t port, AvahiIfIndex if_index,
213
server *new_server = malloc(sizeof(server));
214
if(new_server == NULL){
215
perror_plus("malloc");
218
*new_server = (server){ .ip = strdup(ip),
220
.if_index = if_index,
222
if(new_server->ip == NULL){
223
perror_plus("strdup");
226
/* Special case of first server */
227
if (mc.current_server == NULL){
228
new_server->next = new_server;
229
new_server->prev = new_server;
230
mc.current_server = new_server;
231
/* Place the new server last in the list */
233
new_server->next = mc.current_server;
234
new_server->prev = mc.current_server->prev;
235
new_server->prev->next = new_server;
236
mc.current_server->prev = new_server;
238
ret = clock_gettime(CLOCK_MONOTONIC, &mc.current_server->last_seen);
240
perror_plus("clock_gettime");
249
static bool init_gpgme(const char *seckey, const char *pubkey,
250
const char *tempdir){
76
size_t new_packet_capacity = 0;
77
size_t new_packet_length = 0;
78
252
gpgme_engine_info_t engine_info;
81
fprintf(stderr, "Attempting to decrypt password from gpg packet\n");
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");
85
296
gpgme_check_version(NULL);
86
gpgme_engine_check_version(GPGME_PROTOCOL_OpenPGP);
297
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));
88
/* Set GPGME home directory */
89
rc = gpgme_get_engine_info (&engine_info);
90
if (rc != GPG_ERR_NO_ERROR){
91
fprintf(stderr, "bad gpgme_get_engine_info: %s: %s\n",
92
gpgme_strsource(rc), gpgme_strerror(rc));
304
/* 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));
95
311
while(engine_info != NULL){
96
312
if(engine_info->protocol == GPGME_PROTOCOL_OpenPGP){
97
313
gpgme_set_engine_info(GPGME_PROTOCOL_OpenPGP,
98
engine_info->file_name, homedir);
314
engine_info->file_name, tempdir);
101
317
engine_info = engine_info->next;
103
319
if(engine_info == NULL){
104
fprintf(stderr, "Could not set home dir to %s\n", homedir);
108
/* Create new GPGME data buffer from packet buffer */
109
rc = gpgme_data_new_from_mem(&dh_crypto, packet, packet_size, 0);
110
if (rc != GPG_ERR_NO_ERROR){
111
fprintf(stderr, "bad gpgme_data_new_from_mem: %s: %s\n",
112
gpgme_strsource(rc), gpgme_strerror(rc));
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,
348
gpgme_data_t dh_crypto, dh_plain;
351
size_t plaintext_capacity = 0;
352
ssize_t plaintext_length = 0;
355
fprintf_plus(stderr, "Trying to decrypt OpenPGP data\n");
358
/* Create new GPGME data buffer from memory cryptotext */
359
rc = gpgme_data_new_from_mem(&dh_crypto, cryptotext, crypto_size,
361
if(rc != GPG_ERR_NO_ERROR){
362
fprintf_plus(stderr, "bad gpgme_data_new_from_mem: %s: %s\n",
363
gpgme_strsource(rc), gpgme_strerror(rc));
116
367
/* Create new empty GPGME data buffer for the plaintext */
117
368
rc = gpgme_data_new(&dh_plain);
118
if (rc != GPG_ERR_NO_ERROR){
119
fprintf(stderr, "bad gpgme_data_new: %s: %s\n",
120
gpgme_strsource(rc), gpgme_strerror(rc));
124
/* Create new GPGME "context" */
125
rc = gpgme_new(&ctx);
126
if (rc != GPG_ERR_NO_ERROR){
127
fprintf(stderr, "bad gpgme_new: %s: %s\n",
128
gpgme_strsource(rc), gpgme_strerror(rc));
132
/* Decrypt data from the FILE pointer to the plaintext data buffer */
133
rc = gpgme_op_decrypt(ctx, dh_crypto, dh_plain);
134
if (rc != GPG_ERR_NO_ERROR){
135
fprintf(stderr, "bad gpgme_op_decrypt: %s: %s\n",
136
gpgme_strsource(rc), gpgme_strerror(rc));
141
fprintf(stderr, "decryption of gpg packet succeeded\n");
145
gpgme_decrypt_result_t result;
146
result = gpgme_op_decrypt_result(ctx);
148
fprintf(stderr, "gpgme_op_decrypt_result failed\n");
150
fprintf(stderr, "Unsupported algorithm: %s\n", result->unsupported_algorithm);
151
fprintf(stderr, "Wrong key usage: %d\n", result->wrong_key_usage);
152
if(result->file_name != NULL){
153
fprintf(stderr, "File name: %s\n", result->file_name);
155
gpgme_recipient_t recipient;
156
recipient = result->recipients;
369
if(rc != GPG_ERR_NO_ERROR){
370
fprintf_plus(stderr, "Mandos plugin mandos-client: "
371
"bad gpgme_data_new: %s: %s\n",
372
gpgme_strsource(rc), gpgme_strerror(rc));
373
gpgme_data_release(dh_crypto);
377
/* Decrypt data from the cryptotext data buffer to the plaintext
379
rc = gpgme_op_decrypt(mc.ctx, dh_crypto, dh_plain);
380
if(rc != GPG_ERR_NO_ERROR){
381
fprintf_plus(stderr, "bad gpgme_op_decrypt: %s: %s\n",
382
gpgme_strsource(rc), gpgme_strerror(rc));
383
plaintext_length = -1;
385
gpgme_decrypt_result_t result;
386
result = gpgme_op_decrypt_result(mc.ctx);
388
fprintf_plus(stderr, "gpgme_op_decrypt_result failed\n");
390
fprintf_plus(stderr, "Unsupported algorithm: %s\n",
391
result->unsupported_algorithm);
392
fprintf_plus(stderr, "Wrong key usage: %u\n",
393
result->wrong_key_usage);
394
if(result->file_name != NULL){
395
fprintf_plus(stderr, "File name: %s\n", result->file_name);
397
gpgme_recipient_t recipient;
398
recipient = result->recipients;
158
399
while(recipient != NULL){
159
fprintf(stderr, "Public key algorithm: %s\n",
160
gpgme_pubkey_algo_name(recipient->pubkey_algo));
161
fprintf(stderr, "Key ID: %s\n", recipient->keyid);
162
fprintf(stderr, "Secret key available: %s\n",
163
recipient->status == GPG_ERR_NO_SECKEY ? "No" : "Yes");
400
fprintf_plus(stderr, "Public key algorithm: %s\n",
401
gpgme_pubkey_algo_name
402
(recipient->pubkey_algo));
403
fprintf_plus(stderr, "Key ID: %s\n", recipient->keyid);
404
fprintf_plus(stderr, "Secret key available: %s\n",
405
recipient->status == GPG_ERR_NO_SECKEY
164
407
recipient = recipient->next;
170
/* Delete the GPGME FILE pointer cryptotext data buffer */
171
gpgme_data_release(dh_crypto);
415
fprintf_plus(stderr, "Decryption of OpenPGP data succeeded\n");
173
418
/* Seek back to the beginning of the GPGME plaintext data buffer */
174
gpgme_data_seek(dh_plain, 0, SEEK_SET);
419
if(gpgme_data_seek(dh_plain, (off_t)0, SEEK_SET) == -1){
420
perror_plus("gpgme_data_seek");
421
plaintext_length = -1;
178
if (new_packet_length + BUFFER_SIZE > new_packet_capacity){
179
*new_packet = realloc(*new_packet, new_packet_capacity + BUFFER_SIZE);
180
if (*new_packet == NULL){
184
new_packet_capacity += BUFFER_SIZE;
427
plaintext_capacity = incbuffer(plaintext,
428
(size_t)plaintext_length,
430
if(plaintext_capacity == 0){
431
perror_plus("incbuffer");
432
plaintext_length = -1;
187
ret = gpgme_data_read(dh_plain, *new_packet + new_packet_length, BUFFER_SIZE);
436
ret = gpgme_data_read(dh_plain, *plaintext + plaintext_length,
188
438
/* Print the data, if any */
190
/* If password is empty, then a incorrect error will be printed */
194
perror("gpgme_data_read");
444
perror_plus("gpgme_data_read");
445
plaintext_length = -1;
197
new_packet_length += ret;
448
plaintext_length += ret;
201
fprintf(stderr, "decrypted password is: %s\n", *new_packet);
452
fprintf_plus(stderr, "Decrypted password is: ");
453
for(ssize_t i = 0; i < plaintext_length; i++){
454
fprintf(stderr, "%02hhX ", (*plaintext)[i]);
456
fprintf(stderr, "\n");
204
/* Delete the GPGME plaintext data buffer */
461
/* Delete the GPGME cryptotext data buffer */
462
gpgme_data_release(dh_crypto);
464
/* Delete the GPGME plaintext data buffer */
205
465
gpgme_data_release(dh_plain);
206
return new_packet_length;
466
return plaintext_length;
209
static const char * safer_gnutls_strerror (int value) {
210
const char *ret = gnutls_strerror (value);
469
static const char * safer_gnutls_strerror(int value){
470
const char *ret = gnutls_strerror(value); /* Spurious warning from
471
-Wunreachable-code */
212
473
ret = "(unknown)";
216
void debuggnutls(int level, const char* string){
217
fprintf(stderr, "%s", string);
477
/* GnuTLS log function callback */
478
static void debuggnutls(__attribute__((unused)) int level,
480
fprintf_plus(stderr, "GnuTLS: %s", string);
220
int initgnutls(encrypted_session *es){
483
static int init_gnutls_global(const char *pubkeyfilename,
484
const char *seckeyfilename){
225
fprintf(stderr, "Initializing gnutls\n");
488
fprintf_plus(stderr, "Initializing GnuTLS\n");
229
if ((ret = gnutls_global_init ())
230
!= GNUTLS_E_SUCCESS) {
231
fprintf (stderr, "global_init: %s\n", safer_gnutls_strerror(ret));
491
ret = gnutls_global_init();
492
if(ret != GNUTLS_E_SUCCESS){
493
fprintf_plus(stderr, "GnuTLS global_init: %s\n",
494
safer_gnutls_strerror(ret));
499
/* "Use a log level over 10 to enable all debugging options."
236
502
gnutls_global_set_log_level(11);
237
503
gnutls_global_set_log_function(debuggnutls);
241
/* openpgp credentials */
242
if ((ret = gnutls_certificate_allocate_credentials (&es->cred))
243
!= GNUTLS_E_SUCCESS) {
244
fprintf (stderr, "memory error: %s\n", safer_gnutls_strerror(ret));
506
/* OpenPGP credentials */
507
ret = gnutls_certificate_allocate_credentials(&mc.cred);
508
if(ret != GNUTLS_E_SUCCESS){
509
fprintf_plus(stderr, "GnuTLS memory error: %s\n",
510
safer_gnutls_strerror(ret));
511
gnutls_global_deinit();
249
fprintf(stderr, "Attempting to use openpgp certificate %s"
250
" and keyfile %s as gnutls credentials\n", CERTFILE, KEYFILE);
516
fprintf_plus(stderr, "Attempting to use OpenPGP public key %s and"
517
" secret key %s as GnuTLS credentials\n",
253
522
ret = gnutls_certificate_set_openpgp_key_file
254
(es->cred, CERTFILE, KEYFILE, GNUTLS_OPENPGP_FMT_BASE64);
255
if (ret != GNUTLS_E_SUCCESS) {
257
(stderr, "Error[%d] while reading the OpenPGP key pair ('%s', '%s')\n",
258
ret, CERTFILE, KEYFILE);
259
fprintf(stdout, "The Error is: %s\n",
260
safer_gnutls_strerror(ret));
264
//Gnutls server initialization
265
if ((ret = gnutls_dh_params_init (&es->dh_params))
266
!= GNUTLS_E_SUCCESS) {
267
fprintf (stderr, "Error in dh parameter initialization: %s\n",
268
safer_gnutls_strerror(ret));
272
if ((ret = gnutls_dh_params_generate2 (es->dh_params, DH_BITS))
273
!= GNUTLS_E_SUCCESS) {
274
fprintf (stderr, "Error in prime generation: %s\n",
275
safer_gnutls_strerror(ret));
279
gnutls_certificate_set_dh_params (es->cred, es->dh_params);
281
// Gnutls session creation
282
if ((ret = gnutls_init (&es->session, GNUTLS_SERVER))
283
!= GNUTLS_E_SUCCESS){
284
fprintf(stderr, "Error in gnutls session initialization: %s\n",
285
safer_gnutls_strerror(ret));
288
if ((ret = gnutls_priority_set_direct (es->session, "NORMAL", &err))
289
!= GNUTLS_E_SUCCESS) {
290
fprintf(stderr, "Syntax error at: %s\n", err);
291
fprintf(stderr, "Gnutls error: %s\n",
292
safer_gnutls_strerror(ret));
296
if ((ret = gnutls_credentials_set
297
(es->session, GNUTLS_CRD_CERTIFICATE, es->cred))
298
!= GNUTLS_E_SUCCESS) {
299
fprintf(stderr, "Error setting a credentials set: %s\n",
300
safer_gnutls_strerror(ret));
523
(mc.cred, pubkeyfilename, seckeyfilename,
524
GNUTLS_OPENPGP_FMT_BASE64);
525
if(ret != GNUTLS_E_SUCCESS){
527
"Error[%d] while reading the OpenPGP key pair ('%s',"
528
" '%s')\n", ret, pubkeyfilename, seckeyfilename);
529
fprintf_plus(stderr, "The GnuTLS error is: %s\n",
530
safer_gnutls_strerror(ret));
534
/* GnuTLS server initialization */
535
ret = gnutls_dh_params_init(&mc.dh_params);
536
if(ret != GNUTLS_E_SUCCESS){
537
fprintf_plus(stderr, "Error in GnuTLS DH parameter"
538
" initialization: %s\n",
539
safer_gnutls_strerror(ret));
542
ret = gnutls_dh_params_generate2(mc.dh_params, mc.dh_bits);
543
if(ret != GNUTLS_E_SUCCESS){
544
fprintf_plus(stderr, "Error in GnuTLS prime generation: %s\n",
545
safer_gnutls_strerror(ret));
549
gnutls_certificate_set_dh_params(mc.cred, mc.dh_params);
555
gnutls_certificate_free_credentials(mc.cred);
556
gnutls_global_deinit();
557
gnutls_dh_params_deinit(mc.dh_params);
561
static int init_gnutls_session(gnutls_session_t *session){
563
/* GnuTLS session creation */
565
ret = gnutls_init(session, GNUTLS_SERVER);
569
} while(ret == GNUTLS_E_INTERRUPTED or ret == GNUTLS_E_AGAIN);
570
if(ret != GNUTLS_E_SUCCESS){
572
"Error in GnuTLS session initialization: %s\n",
573
safer_gnutls_strerror(ret));
579
ret = gnutls_priority_set_direct(*session, mc.priority, &err);
581
gnutls_deinit(*session);
584
} while(ret == GNUTLS_E_INTERRUPTED or ret == GNUTLS_E_AGAIN);
585
if(ret != GNUTLS_E_SUCCESS){
586
fprintf_plus(stderr, "Syntax error at: %s\n", err);
587
fprintf_plus(stderr, "GnuTLS error: %s\n",
588
safer_gnutls_strerror(ret));
589
gnutls_deinit(*session);
595
ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,
598
gnutls_deinit(*session);
601
} while(ret == GNUTLS_E_INTERRUPTED or ret == GNUTLS_E_AGAIN);
602
if(ret != GNUTLS_E_SUCCESS){
603
fprintf_plus(stderr, "Error setting GnuTLS credentials: %s\n",
604
safer_gnutls_strerror(ret));
605
gnutls_deinit(*session);
304
609
/* ignore client certificate if any. */
305
gnutls_certificate_server_set_request (es->session, GNUTLS_CERT_IGNORE);
610
gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);
307
gnutls_dh_set_prime_bits (es->session, DH_BITS);
612
gnutls_dh_set_prime_bits(*session, mc.dh_bits);
312
void empty_log(AvahiLogLevel level, const char *txt){}
617
/* Avahi log function callback */
618
static void empty_log(__attribute__((unused)) AvahiLogLevel level,
619
__attribute__((unused)) const char *txt){}
314
int start_mandos_communcation(char *ip, uint16_t port){
316
struct sockaddr_in6 to;
317
struct in6_addr ip_addr;
318
encrypted_session es;
621
/* Called when a Mandos server is found */
622
static int start_mandos_communication(const char *ip, uint16_t port,
623
AvahiIfIndex if_index,
625
int ret, tcp_sd = -1;
628
struct sockaddr_in in;
629
struct sockaddr_in6 in6;
319
631
char *buffer = NULL;
320
char *decrypted_buffer;
632
char *decrypted_buffer = NULL;
321
633
size_t buffer_length = 0;
322
634
size_t buffer_capacity = 0;
323
ssize_t decrypted_buffer_size;
325
const char interface[] = "eth0";
328
fprintf(stderr, "Setting up a tcp connection to %s\n", ip);
331
tcp_sd = socket(PF_INET6, SOCK_STREAM, 0);
338
fprintf(stderr, "Binding to interface %s\n", interface);
341
ret = setsockopt(tcp_sd, SOL_SOCKET, SO_BINDTODEVICE, interface, 5);
343
perror("setsockopt bindtodevice");
347
memset(&to,0,sizeof(to));
348
to.sin6_family = AF_INET6;
349
ret = inet_pton(AF_INET6, ip, &ip_addr);
637
gnutls_session_t session;
638
int pf; /* Protocol family */
655
fprintf_plus(stderr, "Bad address family: %d\n", af);
660
ret = init_gnutls_session(&session);
666
fprintf_plus(stderr, "Setting up a TCP connection to %s, port %"
667
PRIu16 "\n", ip, port);
670
tcp_sd = socket(pf, SOCK_STREAM, 0);
673
perror_plus("socket");
683
memset(&to, 0, sizeof(to));
685
to.in6.sin6_family = (sa_family_t)af;
686
ret = inet_pton(af, ip, &to.in6.sin6_addr);
688
to.in.sin_family = (sa_family_t)af;
689
ret = inet_pton(af, ip, &to.in.sin_addr);
693
perror_plus("inet_pton");
355
fprintf(stderr, "Bad address: %s\n", ip);
358
to.sin6_port = htons(port);
359
to.sin6_scope_id = if_nametoindex(interface);
362
fprintf(stderr, "Connection to: %s\n", ip);
365
ret = connect(tcp_sd, (struct sockaddr *) &to, sizeof(to));
371
ret = initgnutls (&es);
378
gnutls_transport_set_ptr (es.session, (gnutls_transport_ptr_t) tcp_sd);
381
fprintf(stderr, "Establishing tls session with %s\n", ip);
385
ret = gnutls_handshake (es.session);
387
if (ret != GNUTLS_E_SUCCESS){
388
fprintf(stderr, "\n*** Handshake failed ***\n");
394
//Retrieve gpg packet that contains the wanted password
397
fprintf(stderr, "Retrieving pgp encrypted password from %s\n", ip);
401
if (buffer_length + BUFFER_SIZE > buffer_capacity){
402
buffer = realloc(buffer, buffer_capacity + BUFFER_SIZE);
407
buffer_capacity += BUFFER_SIZE;
410
ret = gnutls_record_recv
411
(es.session, buffer+buffer_length, BUFFER_SIZE);
699
fprintf_plus(stderr, "Bad address: %s\n", ip);
704
to.in6.sin6_port = htons(port); /* Spurious warnings from
706
-Wunreachable-code */
708
if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */
709
(&to.in6.sin6_addr)){ /* -Wstrict-aliasing=2 or lower and
711
if(if_index == AVAHI_IF_UNSPEC){
712
fprintf_plus(stderr, "An IPv6 link-local address is"
713
" incomplete without a network interface\n");
717
/* Set the network interface number as scope */
718
to.in6.sin6_scope_id = (uint32_t)if_index;
721
to.in.sin_port = htons(port); /* Spurious warnings from
723
-Wunreachable-code */
732
if(af == AF_INET6 and if_index != AVAHI_IF_UNSPEC){
733
char interface[IF_NAMESIZE];
734
if(if_indextoname((unsigned int)if_index, interface) == NULL){
735
perror_plus("if_indextoname");
737
fprintf_plus(stderr, "Connection to: %s%%%s, port %" PRIu16
738
"\n", ip, interface, port);
741
fprintf_plus(stderr, "Connection to: %s, port %" PRIu16 "\n",
744
char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?
745
INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";
748
pcret = inet_ntop(af, &(to.in6.sin6_addr), addrstr,
751
pcret = inet_ntop(af, &(to.in.sin_addr), addrstr,
755
perror_plus("inet_ntop");
757
if(strcmp(addrstr, ip) != 0){
758
fprintf_plus(stderr, "Canonical address form: %s\n", addrstr);
769
ret = connect(tcp_sd, &to.in6, sizeof(to));
771
ret = connect(tcp_sd, &to.in, sizeof(to)); /* IPv4 */
774
if ((errno != ECONNREFUSED and errno != ENETUNREACH) or debug){
776
perror_plus("connect");
787
const char *out = mandos_protocol_version;
790
size_t out_size = strlen(out);
791
ret = (int)TEMP_FAILURE_RETRY(write(tcp_sd, out + written,
792
out_size - written));
795
perror_plus("write");
799
written += (size_t)ret;
800
if(written < out_size){
803
if(out == mandos_protocol_version){
818
fprintf_plus(stderr, "Establishing TLS session with %s\n", ip);
826
/* This casting via intptr_t is to eliminate warning about casting
827
an int to a pointer type. This is exactly how the GnuTLS Guile
828
function "set-session-transport-fd!" does it. */
829
gnutls_transport_set_ptr(session,
830
(gnutls_transport_ptr_t)(intptr_t)tcp_sd);
838
ret = gnutls_handshake(session);
843
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
845
if(ret != GNUTLS_E_SUCCESS){
847
fprintf_plus(stderr, "*** GnuTLS Handshake failed ***\n");
854
/* Read OpenPGP packet that contains the wanted password */
857
fprintf_plus(stderr, "Retrieving OpenPGP encrypted password from"
868
buffer_capacity = incbuffer(&buffer, buffer_length,
870
if(buffer_capacity == 0){
872
perror_plus("incbuffer");
882
sret = gnutls_record_recv(session, buffer+buffer_length,
417
889
case GNUTLS_E_INTERRUPTED:
418
890
case GNUTLS_E_AGAIN:
420
892
case GNUTLS_E_REHANDSHAKE:
421
ret = gnutls_handshake (es.session);
423
fprintf(stderr, "\n*** Handshake failed ***\n");
894
ret = gnutls_handshake(session);
900
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
902
fprintf_plus(stderr, "*** GnuTLS Re-handshake failed "
430
fprintf(stderr, "Unknown error while reading data from encrypted session with mandos server\n");
432
gnutls_bye (es.session, GNUTLS_SHUT_RDWR);
436
buffer_length += ret;
440
if (buffer_length > 0){
441
if ((decrypted_buffer_size = gpg_packet_decrypt(buffer, buffer_length, &decrypted_buffer, CERT_ROOT)) >= 0){
442
fwrite (decrypted_buffer, 1, decrypted_buffer_size, stdout);
443
free(decrypted_buffer);
910
fprintf_plus(stderr, "Unknown error while reading data from"
911
" encrypted session with Mandos server\n");
912
gnutls_bye(session, GNUTLS_SHUT_RDWR);
917
buffer_length += (size_t) sret;
922
fprintf_plus(stderr, "Closing TLS session\n");
931
ret = gnutls_bye(session, GNUTLS_SHUT_RDWR);
936
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
938
if(buffer_length > 0){
939
ssize_t decrypted_buffer_size;
940
decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,
942
if(decrypted_buffer_size >= 0){
945
while(written < (size_t) decrypted_buffer_size){
951
ret = (int)fwrite(decrypted_buffer + written, 1,
952
(size_t)decrypted_buffer_size - written,
954
if(ret == 0 and ferror(stdout)){
957
fprintf_plus(stderr, "Error writing encrypted data: %s\n",
963
written += (size_t)ret;
969
/* Shutdown procedure */
974
free(decrypted_buffer);
977
ret = (int)TEMP_FAILURE_RETRY(close(tcp_sd));
983
perror_plus("close");
985
gnutls_deinit(session);
452
fprintf(stderr, "Closing tls session\n");
456
gnutls_bye (es.session, GNUTLS_SHUT_RDWR);
459
gnutls_deinit (es.session);
460
gnutls_certificate_free_credentials (es.cred);
461
gnutls_global_deinit ();
465
static AvahiSimplePoll *simple_poll = NULL;
466
static AvahiServer *server = NULL;
468
static void resolve_callback(
469
AvahiSServiceResolver *r,
470
AVAHI_GCC_UNUSED AvahiIfIndex interface,
471
AVAHI_GCC_UNUSED AvahiProtocol protocol,
472
AvahiResolverEvent event,
476
const char *host_name,
477
const AvahiAddress *address,
479
AvahiStringList *txt,
480
AvahiLookupResultFlags flags,
481
AVAHI_GCC_UNUSED void* userdata) {
485
/* Called whenever a service has been resolved successfully or timed out */
488
case AVAHI_RESOLVER_FAILURE:
489
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)));
492
case AVAHI_RESOLVER_FOUND: {
493
char ip[AVAHI_ADDRESS_STR_MAX];
494
avahi_address_snprint(ip, sizeof(ip), address);
496
fprintf(stderr, "Mandos server found at %s on port %d\n", ip, port);
498
int ret = start_mandos_communcation(ip, port);
506
avahi_s_service_resolver_free(r);
509
static void browse_callback(
510
AvahiSServiceBrowser *b,
511
AvahiIfIndex interface,
512
AvahiProtocol protocol,
513
AvahiBrowserEvent event,
517
AVAHI_GCC_UNUSED AvahiLookupResultFlags flags,
520
AvahiServer *s = userdata;
523
/* Called whenever a new services becomes available on the LAN or is removed from the LAN */
527
case AVAHI_BROWSER_FAILURE:
529
fprintf(stderr, "(Browser) %s\n", avahi_strerror(avahi_server_errno(server)));
530
avahi_simple_poll_quit(simple_poll);
533
case AVAHI_BROWSER_NEW:
534
/* We ignore the returned resolver object. In the callback
535
function we free it. If the server is terminated before
536
the callback function is called the server will free
537
the resolver for us. */
539
if (!(avahi_s_service_resolver_new(s, interface, protocol, name, type, domain, AVAHI_PROTO_INET6, 0, resolve_callback, s)))
540
fprintf(stderr, "Failed to resolve service '%s': %s\n", name, avahi_strerror(avahi_server_errno(s)));
544
case AVAHI_BROWSER_REMOVE:
547
case AVAHI_BROWSER_ALL_FOR_NOW:
548
case AVAHI_BROWSER_CACHE_EXHAUSTED:
553
int main(AVAHI_GCC_UNUSED int argc, AVAHI_GCC_UNUSED char*argv[]) {
995
static void resolve_callback(AvahiSServiceResolver *r,
996
AvahiIfIndex interface,
998
AvahiResolverEvent event,
1002
const char *host_name,
1003
const AvahiAddress *address,
1005
AVAHI_GCC_UNUSED AvahiStringList *txt,
1006
AVAHI_GCC_UNUSED AvahiLookupResultFlags
1008
AVAHI_GCC_UNUSED void* userdata){
1011
/* Called whenever a service has been resolved successfully or
1020
case AVAHI_RESOLVER_FAILURE:
1021
fprintf_plus(stderr, "(Avahi Resolver) Failed to resolve service "
1022
"'%s' of type '%s' in domain '%s': %s\n", name, type,
1024
avahi_strerror(avahi_server_errno(mc.server)));
1027
case AVAHI_RESOLVER_FOUND:
1029
char ip[AVAHI_ADDRESS_STR_MAX];
1030
avahi_address_snprint(ip, sizeof(ip), address);
1032
fprintf_plus(stderr, "Mandos server \"%s\" found on %s (%s, %"
1033
PRIdMAX ") on port %" PRIu16 "\n", name,
1034
host_name, ip, (intmax_t)interface, port);
1036
int ret = start_mandos_communication(ip, port, interface,
1037
avahi_proto_to_af(proto));
1039
avahi_simple_poll_quit(mc.simple_poll);
1041
if(not add_server(ip, port, interface,
1042
avahi_proto_to_af(proto))){
1043
fprintf_plus(stderr, "Failed to add server \"%s\" to server"
1049
avahi_s_service_resolver_free(r);
1052
static void browse_callback(AvahiSServiceBrowser *b,
1053
AvahiIfIndex interface,
1054
AvahiProtocol protocol,
1055
AvahiBrowserEvent event,
1059
AVAHI_GCC_UNUSED AvahiLookupResultFlags
1061
AVAHI_GCC_UNUSED void* userdata){
1064
/* Called whenever a new services becomes available on the LAN or
1065
is removed from the LAN */
1073
case AVAHI_BROWSER_FAILURE:
1075
fprintf_plus(stderr, "(Avahi browser) %s\n",
1076
avahi_strerror(avahi_server_errno(mc.server)));
1077
avahi_simple_poll_quit(mc.simple_poll);
1080
case AVAHI_BROWSER_NEW:
1081
/* We ignore the returned Avahi resolver object. In the callback
1082
function we free it. If the Avahi server is terminated before
1083
the callback function is called the Avahi server will free the
1086
if(avahi_s_service_resolver_new(mc.server, interface, protocol,
1087
name, type, domain, protocol, 0,
1088
resolve_callback, NULL) == NULL)
1089
fprintf_plus(stderr, "Avahi: Failed to resolve service '%s':"
1091
avahi_strerror(avahi_server_errno(mc.server)));
1094
case AVAHI_BROWSER_REMOVE:
1097
case AVAHI_BROWSER_ALL_FOR_NOW:
1098
case AVAHI_BROWSER_CACHE_EXHAUSTED:
1100
fprintf_plus(stderr, "No Mandos server found, still"
1107
/* Signal handler that stops main loop after SIGTERM */
1108
static void handle_sigterm(int sig){
1113
signal_received = sig;
1114
int old_errno = errno;
1115
/* set main loop to exit */
1116
if(mc.simple_poll != NULL){
1117
avahi_simple_poll_quit(mc.simple_poll);
1122
bool get_flags(const char *ifname, struct ifreq *ifr){
1125
int s = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1127
perror_plus("socket");
1130
strcpy(ifr->ifr_name, ifname);
1131
ret = ioctl(s, SIOCGIFFLAGS, ifr);
1134
perror_plus("ioctl SIOCGIFFLAGS");
1141
bool good_flags(const char *ifname, const struct ifreq *ifr){
1143
/* Reject the loopback device */
1144
if(ifr->ifr_flags & IFF_LOOPBACK){
1146
fprintf_plus(stderr, "Rejecting loopback interface \"%s\"\n",
1151
/* Accept point-to-point devices only if connect_to is specified */
1152
if(connect_to != NULL and (ifr->ifr_flags & IFF_POINTOPOINT)){
1154
fprintf_plus(stderr, "Accepting point-to-point interface"
1155
" \"%s\"\n", ifname);
1159
/* Otherwise, reject non-broadcast-capable devices */
1160
if(not (ifr->ifr_flags & IFF_BROADCAST)){
1162
fprintf_plus(stderr, "Rejecting non-broadcast interface"
1163
" \"%s\"\n", ifname);
1167
/* Reject non-ARP interfaces (including dummy interfaces) */
1168
if(ifr->ifr_flags & IFF_NOARP){
1170
fprintf_plus(stderr, "Rejecting non-ARP interface \"%s\"\n",
1176
/* Accept this device */
1178
fprintf_plus(stderr, "Interface \"%s\" is good\n", ifname);
1184
* This function determines if a directory entry in /sys/class/net
1185
* corresponds to an acceptable network device.
1186
* (This function is passed to scandir(3) as a filter function.)
1188
int good_interface(const struct dirent *if_entry){
1189
if(if_entry->d_name[0] == '.'){
1194
if(not get_flags(if_entry->d_name, &ifr)){
1196
fprintf_plus(stderr, "Failed to get flags for interface "
1197
"\"%s\"\n", if_entry->d_name);
1202
if(not good_flags(if_entry->d_name, &ifr)){
1209
* This function determines if a directory entry in /sys/class/net
1210
* corresponds to an acceptable network device which is up.
1211
* (This function is passed to scandir(3) as a filter function.)
1213
int up_interface(const struct dirent *if_entry){
1214
if(if_entry->d_name[0] == '.'){
1219
if(not get_flags(if_entry->d_name, &ifr)){
1221
fprintf_plus(stderr, "Failed to get flags for interface "
1222
"\"%s\"\n", if_entry->d_name);
1227
/* Reject down interfaces */
1228
if(not (ifr.ifr_flags & IFF_UP)){
1230
fprintf_plus(stderr, "Rejecting down interface \"%s\"\n",
1236
/* Reject non-running interfaces */
1237
if(not (ifr.ifr_flags & IFF_RUNNING)){
1239
fprintf_plus(stderr, "Rejecting non-running interface \"%s\"\n",
1245
if(not good_flags(if_entry->d_name, &ifr)){
1251
int notdotentries(const struct dirent *direntry){
1252
/* Skip "." and ".." */
1253
if(direntry->d_name[0] == '.'
1254
and (direntry->d_name[1] == '\0'
1255
or (direntry->d_name[1] == '.'
1256
and direntry->d_name[2] == '\0'))){
1262
/* Is this directory entry a runnable program? */
1263
int runnable_hook(const struct dirent *direntry){
1268
if((direntry->d_name)[0] == '\0'){
1273
sret = strspn(direntry->d_name, "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
1274
"abcdefghijklmnopqrstuvwxyz"
1277
if((direntry->d_name)[sret] != '\0'){
1278
/* Contains non-allowed characters */
1280
fprintf_plus(stderr, "Ignoring hook \"%s\" with bad name\n",
1286
char *fullname = NULL;
1287
ret = asprintf(&fullname, "%s/%s", hookdir, direntry->d_name);
1289
perror_plus("asprintf");
1293
ret = stat(fullname, &st);
1296
perror_plus("Could not stat hook");
1300
if(not (S_ISREG(st.st_mode))){
1301
/* Not a regular file */
1303
fprintf_plus(stderr, "Ignoring hook \"%s\" - not a file\n",
1308
if(not (st.st_mode & (S_IXUSR | S_IXGRP | S_IXOTH))){
1309
/* Not executable */
1311
fprintf_plus(stderr, "Ignoring hook \"%s\" - not executable\n",
1317
fprintf_plus(stderr, "Hook \"%s\" is acceptable\n",
1323
int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval){
1325
struct timespec now;
1326
struct timespec waited_time;
1327
intmax_t block_time;
1330
if(mc.current_server == NULL){
1332
fprintf_plus(stderr, "Wait until first server is found."
1335
ret = avahi_simple_poll_iterate(s, -1);
1338
fprintf_plus(stderr, "Check current_server if we should run"
1341
/* the current time */
1342
ret = clock_gettime(CLOCK_MONOTONIC, &now);
1344
perror_plus("clock_gettime");
1347
/* Calculating in ms how long time between now and server
1348
who we visted longest time ago. Now - last seen. */
1349
waited_time.tv_sec = (now.tv_sec
1350
- mc.current_server->last_seen.tv_sec);
1351
waited_time.tv_nsec = (now.tv_nsec
1352
- mc.current_server->last_seen.tv_nsec);
1353
/* total time is 10s/10,000ms.
1354
Converting to s from ms by dividing by 1,000,
1355
and ns to ms by dividing by 1,000,000. */
1356
block_time = ((retry_interval
1357
- ((intmax_t)waited_time.tv_sec * 1000))
1358
- ((intmax_t)waited_time.tv_nsec / 1000000));
1361
fprintf_plus(stderr, "Blocking for %" PRIdMAX " ms\n",
1365
if(block_time <= 0){
1366
ret = start_mandos_communication(mc.current_server->ip,
1367
mc.current_server->port,
1368
mc.current_server->if_index,
1369
mc.current_server->af);
1371
avahi_simple_poll_quit(mc.simple_poll);
1374
ret = clock_gettime(CLOCK_MONOTONIC,
1375
&mc.current_server->last_seen);
1377
perror_plus("clock_gettime");
1380
mc.current_server = mc.current_server->next;
1381
block_time = 0; /* Call avahi to find new Mandos
1382
servers, but don't block */
1385
ret = avahi_simple_poll_iterate(s, (int)block_time);
1388
if (ret > 0 or errno != EINTR){
1389
return (ret != 1) ? ret : 0;
1395
/* Set effective uid to 0, return errno */
1396
int raise_privileges(void){
1397
int old_errno = errno;
1400
if(seteuid(0) == -1){
1401
perror_plus("seteuid");
1408
/* Set effective and real user ID to 0. Return errno. */
1409
int raise_privileges_permanently(void){
1410
int old_errno = errno;
1411
int ret_errno = raise_privileges();
1417
if(setuid(0) == -1){
1418
perror_plus("seteuid");
1425
/* Set effective user ID to unprivileged saved user ID */
1426
int lower_privileges(void){
1427
int old_errno = errno;
1430
if(seteuid(uid) == -1){
1431
perror_plus("seteuid");
1438
bool run_network_hooks(const char *mode, const char *interface,
1440
struct dirent **direntries;
1441
struct dirent *direntry;
1443
int numhooks = scandir(hookdir, &direntries, runnable_hook,
1446
perror_plus("scandir");
1448
int devnull = open("/dev/null", O_RDONLY);
1449
for(int i = 0; i < numhooks; i++){
1450
direntry = direntries[i];
1451
char *fullname = NULL;
1452
ret = asprintf(&fullname, "%s/%s", hookdir, direntry->d_name);
1454
perror_plus("asprintf");
1458
fprintf_plus(stderr, "Running network hook \"%s\"\n",
1461
pid_t hook_pid = fork();
1464
/* Raise privileges */
1465
raise_privileges_permanently();
1470
perror_plus("setgid");
1472
/* Reset supplementary groups */
1474
ret = setgroups(0, NULL);
1476
perror_plus("setgroups");
1478
dup2(devnull, STDIN_FILENO);
1480
dup2(STDERR_FILENO, STDOUT_FILENO);
1481
ret = setenv("MANDOSNETHOOKDIR", hookdir, 1);
1483
perror_plus("setenv");
1486
ret = setenv("DEVICE", interface, 1);
1488
perror_plus("setenv");
1491
ret = setenv("VERBOSITY", debug ? "1" : "0", 1);
1493
perror_plus("setenv");
1496
ret = setenv("MODE", mode, 1);
1498
perror_plus("setenv");
1502
ret = asprintf(&delaystring, "%f", delay);
1504
perror_plus("asprintf");
1507
ret = setenv("DELAY", delaystring, 1);
1510
perror_plus("setenv");
1514
if(connect_to != NULL){
1515
ret = setenv("CONNECT", connect_to, 1);
1517
perror_plus("setenv");
1521
if(execl(fullname, direntry->d_name, mode, NULL) == -1){
1522
perror_plus("execl");
1523
_exit(EXIT_FAILURE);
1527
if(TEMP_FAILURE_RETRY(waitpid(hook_pid, &status, 0)) == -1){
1528
perror_plus("waitpid");
1532
if(WIFEXITED(status)){
1533
if(WEXITSTATUS(status) != 0){
1534
fprintf_plus(stderr, "Warning: network hook \"%s\" exited"
1535
" with status %d\n", direntry->d_name,
1536
WEXITSTATUS(status));
1540
} else if(WIFSIGNALED(status)){
1541
fprintf_plus(stderr, "Warning: network hook \"%s\" died by"
1542
" signal %d\n", direntry->d_name,
1547
fprintf_plus(stderr, "Warning: network hook \"%s\""
1548
" crashed\n", direntry->d_name);
1555
fprintf_plus(stderr, "Network hook \"%s\" ran successfully\n",
1564
int bring_up_interface(const char * const interface, const float delay){
1566
int old_errno = errno;
1569
struct ifreq network;
1570
AvahiIfIndex if_index = (AvahiIfIndex)if_nametoindex(interface);
1572
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
1582
/* Re-raise priviliges */
1586
/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO
1587
messages about the network interface to mess up the prompt */
1588
ret = klogctl(8, NULL, 5);
1589
bool restore_loglevel = true;
1591
restore_loglevel = false;
1592
perror_plus("klogctl");
1594
#endif /* __linux__ */
1596
sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1599
perror_plus("socket");
1601
if(restore_loglevel){
1602
ret = klogctl(7, NULL, 0);
1604
perror_plus("klogctl");
1607
#endif /* __linux__ */
1608
/* Lower privileges */
1613
strcpy(network.ifr_name, interface);
1614
ret = ioctl(sd, SIOCGIFFLAGS, &network);
1617
perror_plus("ioctl SIOCGIFFLAGS");
1619
if(restore_loglevel){
1620
ret = klogctl(7, NULL, 0);
1622
perror_plus("klogctl");
1625
#endif /* __linux__ */
1626
/* Lower privileges */
1631
if((network.ifr_flags & IFF_UP) == 0){
1632
network.ifr_flags |= IFF_UP;
1633
ret = ioctl(sd, SIOCSIFFLAGS, &network);
1636
perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");
1638
if(restore_loglevel){
1639
ret = klogctl(7, NULL, 0);
1641
perror_plus("klogctl");
1644
#endif /* __linux__ */
1645
/* Lower privileges */
1651
/* Sleep checking until interface is running.
1652
Check every 0.25s, up to total time of delay */
1653
for(int i=0; i < delay * 4; i++){
1654
ret = ioctl(sd, SIOCGIFFLAGS, &network);
1656
perror_plus("ioctl SIOCGIFFLAGS");
1657
} else if(network.ifr_flags & IFF_RUNNING){
1660
struct timespec sleeptime = { .tv_nsec = 250000000 };
1661
ret = nanosleep(&sleeptime, NULL);
1662
if(ret == -1 and errno != EINTR){
1663
perror_plus("nanosleep");
1666
/* Close the socket */
1667
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1669
perror_plus("close");
1672
if(restore_loglevel){
1673
/* Restores kernel loglevel to default */
1674
ret = klogctl(7, NULL, 0);
1676
perror_plus("klogctl");
1679
#endif /* __linux__ */
1680
/* Lower privileges */
1686
int main(int argc, char *argv[]){
1687
AvahiSServiceBrowser *sb = NULL;
1692
int exitcode = EXIT_SUCCESS;
1693
const char *interface = "";
1694
struct ifreq network;
1696
bool take_down_interface = false;
1697
char tempdir[] = "/tmp/mandosXXXXXX";
1698
bool tempdir_created = false;
1699
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
1700
const char *seckey = PATHDIR "/" SECKEY;
1701
const char *pubkey = PATHDIR "/" PUBKEY;
1703
bool gnutls_initialized = false;
1704
bool gpgme_initialized = false;
1706
double retry_interval = 10; /* 10s between trying a server and
1707
retrying the same server again */
1709
struct sigaction old_sigterm_action = { .sa_handler = SIG_DFL };
1710
struct sigaction sigterm_action = { .sa_handler = handle_sigterm };
1715
/* Lower any group privileges we might have, just to be safe */
1719
perror_plus("setgid");
1722
/* Lower user privileges (temporarily) */
1726
perror_plus("seteuid");
1734
struct argp_option options[] = {
1735
{ .name = "debug", .key = 128,
1736
.doc = "Debug mode", .group = 3 },
1737
{ .name = "connect", .key = 'c',
1738
.arg = "ADDRESS:PORT",
1739
.doc = "Connect directly to a specific Mandos server",
1741
{ .name = "interface", .key = 'i',
1743
.doc = "Network interface that will be used to search for"
1746
{ .name = "seckey", .key = 's',
1748
.doc = "OpenPGP secret key file base name",
1750
{ .name = "pubkey", .key = 'p',
1752
.doc = "OpenPGP public key file base name",
1754
{ .name = "dh-bits", .key = 129,
1756
.doc = "Bit length of the prime number used in the"
1757
" Diffie-Hellman key exchange",
1759
{ .name = "priority", .key = 130,
1761
.doc = "GnuTLS priority string for the TLS handshake",
1763
{ .name = "delay", .key = 131,
1765
.doc = "Maximum delay to wait for interface startup",
1767
{ .name = "retry", .key = 132,
1769
.doc = "Retry interval used when denied by the Mandos server",
1771
{ .name = "network-hook-dir", .key = 133,
1773
.doc = "Directory where network hooks are located",
1776
* These reproduce what we would get without ARGP_NO_HELP
1778
{ .name = "help", .key = '?',
1779
.doc = "Give this help list", .group = -1 },
1780
{ .name = "usage", .key = -3,
1781
.doc = "Give a short usage message", .group = -1 },
1782
{ .name = "version", .key = 'V',
1783
.doc = "Print program version", .group = -1 },
1787
error_t parse_opt(int key, char *arg,
1788
struct argp_state *state){
1791
case 128: /* --debug */
1794
case 'c': /* --connect */
1797
case 'i': /* --interface */
1800
case 's': /* --seckey */
1803
case 'p': /* --pubkey */
1806
case 129: /* --dh-bits */
1808
tmpmax = strtoimax(arg, &tmp, 10);
1809
if(errno != 0 or tmp == arg or *tmp != '\0'
1810
or tmpmax != (typeof(mc.dh_bits))tmpmax){
1811
argp_error(state, "Bad number of DH bits");
1813
mc.dh_bits = (typeof(mc.dh_bits))tmpmax;
1815
case 130: /* --priority */
1818
case 131: /* --delay */
1820
delay = strtof(arg, &tmp);
1821
if(errno != 0 or tmp == arg or *tmp != '\0'){
1822
argp_error(state, "Bad delay");
1824
case 132: /* --retry */
1826
retry_interval = strtod(arg, &tmp);
1827
if(errno != 0 or tmp == arg or *tmp != '\0'
1828
or (retry_interval * 1000) > INT_MAX
1829
or retry_interval < 0){
1830
argp_error(state, "Bad retry interval");
1833
case 133: /* --network-hook-dir */
1837
* These reproduce what we would get without ARGP_NO_HELP
1839
case '?': /* --help */
1840
argp_state_help(state, state->out_stream,
1841
(ARGP_HELP_STD_HELP | ARGP_HELP_EXIT_ERR)
1842
& ~(unsigned int)ARGP_HELP_EXIT_OK);
1843
case -3: /* --usage */
1844
argp_state_help(state, state->out_stream,
1845
ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);
1846
case 'V': /* --version */
1847
fprintf_plus(state->out_stream, "%s\n", argp_program_version);
1848
exit(argp_err_exit_status);
1851
return ARGP_ERR_UNKNOWN;
1856
struct argp argp = { .options = options, .parser = parse_opt,
1858
.doc = "Mandos client -- Get and decrypt"
1859
" passwords from a Mandos server" };
1860
ret = argp_parse(&argp, argc, argv,
1861
ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);
1868
perror_plus("argp_parse");
1869
exitcode = EX_OSERR;
1872
exitcode = EX_USAGE;
1878
/* Work around Debian bug #633582:
1879
<http://bugs.debian.org/633582> */
1881
/* Re-raise priviliges */
1882
if(raise_privileges() == 0){
1885
if(strcmp(seckey, PATHDIR "/" SECKEY) == 0){
1886
int seckey_fd = open(seckey, O_RDONLY);
1887
if(seckey_fd == -1){
1888
perror_plus("open");
1890
ret = (int)TEMP_FAILURE_RETRY(fstat(seckey_fd, &st));
1892
perror_plus("fstat");
1894
if(S_ISREG(st.st_mode)
1895
and st.st_uid == 0 and st.st_gid == 0){
1896
ret = fchown(seckey_fd, uid, gid);
1898
perror_plus("fchown");
1902
TEMP_FAILURE_RETRY(close(seckey_fd));
1906
if(strcmp(pubkey, PATHDIR "/" PUBKEY) == 0){
1907
int pubkey_fd = open(pubkey, O_RDONLY);
1908
if(pubkey_fd == -1){
1909
perror_plus("open");
1911
ret = (int)TEMP_FAILURE_RETRY(fstat(pubkey_fd, &st));
1913
perror_plus("fstat");
1915
if(S_ISREG(st.st_mode)
1916
and st.st_uid == 0 and st.st_gid == 0){
1917
ret = fchown(pubkey_fd, uid, gid);
1919
perror_plus("fchown");
1923
TEMP_FAILURE_RETRY(close(pubkey_fd));
1927
/* Lower privileges */
1931
perror_plus("seteuid");
1936
/* Run network hooks */
1937
if(not run_network_hooks("start", interface, delay)){
1942
avahi_set_log_function(empty_log);
1945
if(interface[0] == '\0'){
1946
struct dirent **direntries;
1947
/* First look for interfaces that are up */
1948
ret = scandir(sys_class_net, &direntries, up_interface,
1951
/* No up interfaces, look for any good interfaces */
1953
ret = scandir(sys_class_net, &direntries, good_interface,
1957
/* Pick the first interface returned */
1958
interface = strdup(direntries[0]->d_name);
1960
fprintf_plus(stderr, "Using interface \"%s\"\n", interface);
1962
if(interface == NULL){
1963
perror_plus("malloc");
1965
exitcode = EXIT_FAILURE;
1971
fprintf_plus(stderr, "Could not find a network interface\n");
1972
exitcode = EXIT_FAILURE;
1977
/* Initialize Avahi early so avahi_simple_poll_quit() can be called
1978
from the signal handler */
1979
/* Initialize the pseudo-RNG for Avahi */
1980
srand((unsigned int) time(NULL));
1981
mc.simple_poll = avahi_simple_poll_new();
1982
if(mc.simple_poll == NULL){
1983
fprintf_plus(stderr,
1984
"Avahi: Failed to create simple poll object.\n");
1985
exitcode = EX_UNAVAILABLE;
1989
sigemptyset(&sigterm_action.sa_mask);
1990
ret = sigaddset(&sigterm_action.sa_mask, SIGINT);
1992
perror_plus("sigaddset");
1993
exitcode = EX_OSERR;
1996
ret = sigaddset(&sigterm_action.sa_mask, SIGHUP);
1998
perror_plus("sigaddset");
1999
exitcode = EX_OSERR;
2002
ret = sigaddset(&sigterm_action.sa_mask, SIGTERM);
2004
perror_plus("sigaddset");
2005
exitcode = EX_OSERR;
2008
/* Need to check if the handler is SIG_IGN before handling:
2009
| [[info:libc:Initial Signal Actions]] |
2010
| [[info:libc:Basic Signal Handling]] |
2012
ret = sigaction(SIGINT, NULL, &old_sigterm_action);
2014
perror_plus("sigaction");
2017
if(old_sigterm_action.sa_handler != SIG_IGN){
2018
ret = sigaction(SIGINT, &sigterm_action, NULL);
2020
perror_plus("sigaction");
2021
exitcode = EX_OSERR;
2025
ret = sigaction(SIGHUP, NULL, &old_sigterm_action);
2027
perror_plus("sigaction");
2030
if(old_sigterm_action.sa_handler != SIG_IGN){
2031
ret = sigaction(SIGHUP, &sigterm_action, NULL);
2033
perror_plus("sigaction");
2034
exitcode = EX_OSERR;
2038
ret = sigaction(SIGTERM, NULL, &old_sigterm_action);
2040
perror_plus("sigaction");
2043
if(old_sigterm_action.sa_handler != SIG_IGN){
2044
ret = sigaction(SIGTERM, &sigterm_action, NULL);
2046
perror_plus("sigaction");
2047
exitcode = EX_OSERR;
2052
/* If the interface is down, bring it up */
2053
if((interface[0] != '\0') and (strcmp(interface, "none") != 0)){
2054
ret = bring_up_interface(interface, delay);
2057
perror_plus("Failed to bring up interface");
2065
ret = init_gnutls_global(pubkey, seckey);
2067
fprintf_plus(stderr, "init_gnutls_global failed\n");
2068
exitcode = EX_UNAVAILABLE;
2071
gnutls_initialized = true;
2078
if(mkdtemp(tempdir) == NULL){
2079
perror_plus("mkdtemp");
2082
tempdir_created = true;
2088
if(not init_gpgme(pubkey, seckey, tempdir)){
2089
fprintf_plus(stderr, "init_gpgme failed\n");
2090
exitcode = EX_UNAVAILABLE;
2093
gpgme_initialized = true;
2100
if(connect_to != NULL){
2101
/* Connect directly, do not use Zeroconf */
2102
/* (Mainly meant for debugging) */
2103
char *address = strrchr(connect_to, ':');
2105
if(address == NULL){
2106
fprintf_plus(stderr, "No colon in address\n");
2107
exitcode = EX_USAGE;
2117
tmpmax = strtoimax(address+1, &tmp, 10);
2118
if(errno != 0 or tmp == address+1 or *tmp != '\0'
2119
or tmpmax != (uint16_t)tmpmax){
2120
fprintf_plus(stderr, "Bad port number\n");
2121
exitcode = EX_USAGE;
2129
port = (uint16_t)tmpmax;
2131
/* Colon in address indicates IPv6 */
2133
if(strchr(connect_to, ':') != NULL){
2135
/* Accept [] around IPv6 address - see RFC 5952 */
2136
if(connect_to[0] == '[' and address[-1] == ']')
2144
address = connect_to;
2150
while(not quit_now){
2151
ret = start_mandos_communication(address, port, if_index, af);
2152
if(quit_now or ret == 0){
2156
fprintf_plus(stderr, "Retrying in %d seconds\n",
2157
(int)retry_interval);
2159
sleep((int)retry_interval);
2163
exitcode = EXIT_SUCCESS;
554
2174
AvahiServerConfig config;
555
AvahiSServiceBrowser *sb = NULL;
556
const char db[] = "--debug";
559
int returncode = EXIT_SUCCESS;
560
char *basename = rindex(argv[0], '/');
561
if(basename == NULL){
567
char *program_name = malloc(strlen(basename) + sizeof(db));
569
if (program_name == NULL){
574
program_name[0] = '\0';
576
for (int i = 1; i < argc; i++){
577
if (not strncmp(argv[i], db, 5)){
578
strcat(strcat(strcat(program_name, db ), "="), basename);
579
if(not strcmp(argv[i], db) or not strcmp(argv[i], program_name)){
587
avahi_set_log_function(empty_log);
590
/* Initialize the psuedo-RNG */
593
/* Allocate main loop object */
594
if (!(simple_poll = avahi_simple_poll_new())) {
595
fprintf(stderr, "Failed to create simple poll object.\n");
600
/* Do not publish any local records */
2175
/* Do not publish any local Zeroconf records */
601
2176
avahi_server_config_init(&config);
602
2177
config.publish_hinfo = 0;
603
2178
config.publish_addresses = 0;
604
2179
config.publish_workstation = 0;
605
2180
config.publish_domain = 0;
607
2182
/* Allocate a new server */
608
server = avahi_server_new(avahi_simple_poll_get(simple_poll), &config, NULL, NULL, &error);
610
/* Free the configuration data */
2183
mc.server = avahi_server_new(avahi_simple_poll_get
2184
(mc.simple_poll), &config, NULL,
2187
/* Free the Avahi configuration data */
611
2188
avahi_server_config_free(&config);
613
/* Check if creating the server object succeeded */
615
fprintf(stderr, "Failed to create server: %s\n", avahi_strerror(error));
616
returncode = EXIT_FAILURE;
620
/* Create the service browser */
621
if (!(sb = avahi_s_service_browser_new(server, if_nametoindex("eth0"), AVAHI_PROTO_INET6, "_mandos._tcp", NULL, 0, browse_callback, server))) {
622
fprintf(stderr, "Failed to create service browser: %s\n", avahi_strerror(avahi_server_errno(server)));
623
returncode = EXIT_FAILURE;
627
/* Run the main loop */
630
fprintf(stderr, "Starting avahi loop search\n");
633
avahi_simple_poll_loop(simple_poll);
638
fprintf(stderr, "%s exiting\n", argv[0]);
643
avahi_s_service_browser_free(sb);
646
avahi_server_free(server);
649
avahi_simple_poll_free(simple_poll);
2191
/* Check if creating the Avahi server object succeeded */
2192
if(mc.server == NULL){
2193
fprintf_plus(stderr, "Failed to create Avahi server: %s\n",
2194
avahi_strerror(error));
2195
exitcode = EX_UNAVAILABLE;
2203
/* Create the Avahi service browser */
2204
sb = avahi_s_service_browser_new(mc.server, if_index,
2205
AVAHI_PROTO_UNSPEC, "_mandos._tcp",
2206
NULL, 0, browse_callback, NULL);
2208
fprintf_plus(stderr, "Failed to create service browser: %s\n",
2209
avahi_strerror(avahi_server_errno(mc.server)));
2210
exitcode = EX_UNAVAILABLE;
2218
/* Run the main loop */
2221
fprintf_plus(stderr, "Starting Avahi loop search\n");
2224
ret = avahi_loop_with_timeout(mc.simple_poll,
2225
(int)(retry_interval * 1000));
2227
fprintf_plus(stderr, "avahi_loop_with_timeout exited %s\n",
2228
(ret == 0) ? "successfully" : "with error");
2234
fprintf_plus(stderr, "%s exiting\n", argv[0]);
2237
/* Cleanup things */
2239
avahi_s_service_browser_free(sb);
2241
if(mc.server != NULL)
2242
avahi_server_free(mc.server);
2244
if(mc.simple_poll != NULL)
2245
avahi_simple_poll_free(mc.simple_poll);
2247
if(gnutls_initialized){
2248
gnutls_certificate_free_credentials(mc.cred);
2249
gnutls_global_deinit();
2250
gnutls_dh_params_deinit(mc.dh_params);
2253
if(gpgme_initialized){
2254
gpgme_release(mc.ctx);
2257
/* Cleans up the circular linked list of Mandos servers the client
2259
if(mc.current_server != NULL){
2260
mc.current_server->prev->next = NULL;
2261
while(mc.current_server != NULL){
2262
server *next = mc.current_server->next;
2263
free(mc.current_server);
2264
mc.current_server = next;
2268
/* Run network hooks */
2269
run_network_hooks("stop", interface, delay);
2271
/* Re-raise priviliges */
2275
/* Take down the network interface */
2276
if(take_down_interface and geteuid() == 0){
2277
ret = ioctl(sd, SIOCGIFFLAGS, &network);
2279
perror_plus("ioctl SIOCGIFFLAGS");
2280
} else if(network.ifr_flags & IFF_UP){
2281
network.ifr_flags &= ~(short)IFF_UP; /* clear flag */
2282
ret = ioctl(sd, SIOCSIFFLAGS, &network);
2284
perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");
2287
ret = (int)TEMP_FAILURE_RETRY(close(sd));
2289
perror_plus("close");
2293
/* Lower privileges permanently */
2297
perror_plus("setuid");
2300
/* Removes the GPGME temp directory and all files inside */
2301
if(tempdir_created){
2302
struct dirent **direntries = NULL;
2303
struct dirent *direntry = NULL;
2304
int numentries = scandir(tempdir, &direntries, notdotentries,
2306
if (numentries > 0){
2307
for(int i = 0; i < numentries; i++){
2308
direntry = direntries[i];
2309
char *fullname = NULL;
2310
ret = asprintf(&fullname, "%s/%s", tempdir,
2313
perror_plus("asprintf");
2316
ret = remove(fullname);
2318
fprintf_plus(stderr, "remove(\"%s\"): %s\n", fullname,
2325
/* need to clean even if 0 because man page doesn't specify */
2327
if (numentries == -1){
2328
perror_plus("scandir");
2330
ret = rmdir(tempdir);
2331
if(ret == -1 and errno != ENOENT){
2332
perror_plus("rmdir");
2337
sigemptyset(&old_sigterm_action.sa_mask);
2338
old_sigterm_action.sa_handler = SIG_DFL;
2339
ret = (int)TEMP_FAILURE_RETRY(sigaction(signal_received,
2340
&old_sigterm_action,
2343
perror_plus("sigaction");
2346
ret = raise(signal_received);
2347
} while(ret != 0 and errno == EINTR);
2349
perror_plus("raise");
2352
TEMP_FAILURE_RETRY(pause());