104
47
#include <avahi-common/malloc.h>
105
48
#include <avahi-common/error.h>
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,
51
#include <sys/types.h> /* socket(), inet_pton() */
52
#include <sys/socket.h> /* socket(), struct sockaddr_in6,
53
struct in6_addr, inet_pton() */
54
#include <gnutls/gnutls.h> /* All GnuTLS stuff */
55
#include <gnutls/openpgp.h> /* GnuTLS with openpgp stuff */
57
#include <unistd.h> /* close() */
58
#include <netinet/in.h>
59
#include <stdbool.h> /* true */
60
#include <string.h> /* memset */
61
#include <arpa/inet.h> /* inet_pton() */
62
#include <iso646.h> /* not */
65
#include <errno.h> /* perror() */
72
#define CERT_ROOT "/conf/conf.d/cryptkeyreq/"
74
#define CERTFILE CERT_ROOT "openpgp-client.txt"
75
#define KEYFILE CERT_ROOT "openpgp-client-key.txt"
124
76
#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"
131
79
bool debug = false;
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 */
154
AvahiSimplePoll *simple_poll;
82
gnutls_session_t session;
156
83
gnutls_certificate_credentials_t cred;
157
unsigned int dh_bits;
158
84
gnutls_dh_params_t dh_params;
159
const char *priority;
88
ssize_t pgp_packet_decrypt (char *packet, size_t packet_size,
89
char **new_packet, const char *homedir){
90
gpgme_data_t dh_crypto, dh_plain;
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){
94
ssize_t new_packet_capacity = 0;
95
ssize_t new_packet_length = 0;
252
96
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");
99
fprintf(stderr, "Trying to decrypt OpenPGP packet\n");
296
103
gpgme_check_version(NULL);
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));
104
gpgme_engine_check_version(GPGME_PROTOCOL_OpenPGP);
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));
106
/* Set GPGME home directory */
107
rc = gpgme_get_engine_info (&engine_info);
108
if (rc != GPG_ERR_NO_ERROR){
109
fprintf(stderr, "bad gpgme_get_engine_info: %s: %s\n",
110
gpgme_strsource(rc), gpgme_strerror(rc));
311
113
while(engine_info != NULL){
312
114
if(engine_info->protocol == GPGME_PROTOCOL_OpenPGP){
313
115
gpgme_set_engine_info(GPGME_PROTOCOL_OpenPGP,
314
engine_info->file_name, tempdir);
116
engine_info->file_name, homedir);
317
119
engine_info = engine_info->next;
319
121
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,
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));
122
fprintf(stderr, "Could not set home dir to %s\n", homedir);
126
/* Create new GPGME data buffer from packet buffer */
127
rc = gpgme_data_new_from_mem(&dh_crypto, packet, packet_size, 0);
128
if (rc != GPG_ERR_NO_ERROR){
129
fprintf(stderr, "bad gpgme_data_new_from_mem: %s: %s\n",
130
gpgme_strsource(rc), gpgme_strerror(rc));
367
134
/* Create new empty GPGME data buffer for the plaintext */
368
135
rc = gpgme_data_new(&dh_plain);
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;
136
if (rc != GPG_ERR_NO_ERROR){
137
fprintf(stderr, "bad gpgme_data_new: %s: %s\n",
138
gpgme_strsource(rc), gpgme_strerror(rc));
142
/* Create new GPGME "context" */
143
rc = gpgme_new(&ctx);
144
if (rc != GPG_ERR_NO_ERROR){
145
fprintf(stderr, "bad gpgme_new: %s: %s\n",
146
gpgme_strsource(rc), gpgme_strerror(rc));
150
/* Decrypt data from the FILE pointer to the plaintext data
152
rc = gpgme_op_decrypt(ctx, dh_crypto, dh_plain);
153
if (rc != GPG_ERR_NO_ERROR){
154
fprintf(stderr, "bad gpgme_op_decrypt: %s: %s\n",
155
gpgme_strsource(rc), gpgme_strerror(rc));
160
fprintf(stderr, "Decryption of OpenPGP packet succeeded\n");
164
gpgme_decrypt_result_t result;
165
result = gpgme_op_decrypt_result(ctx);
167
fprintf(stderr, "gpgme_op_decrypt_result failed\n");
169
fprintf(stderr, "Unsupported algorithm: %s\n",
170
result->unsupported_algorithm);
171
fprintf(stderr, "Wrong key usage: %d\n",
172
result->wrong_key_usage);
173
if(result->file_name != NULL){
174
fprintf(stderr, "File name: %s\n", result->file_name);
176
gpgme_recipient_t recipient;
177
recipient = result->recipients;
399
179
while(recipient != NULL){
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
180
fprintf(stderr, "Public key algorithm: %s\n",
181
gpgme_pubkey_algo_name(recipient->pubkey_algo));
182
fprintf(stderr, "Key ID: %s\n", recipient->keyid);
183
fprintf(stderr, "Secret key available: %s\n",
184
recipient->status == GPG_ERR_NO_SECKEY
407
186
recipient = recipient->next;
415
fprintf_plus(stderr, "Decryption of OpenPGP data succeeded\n");
192
/* Delete the GPGME FILE pointer cryptotext data buffer */
193
gpgme_data_release(dh_crypto);
418
195
/* Seek back to the beginning of the GPGME plaintext data buffer */
419
if(gpgme_data_seek(dh_plain, (off_t)0, SEEK_SET) == -1){
420
perror_plus("gpgme_data_seek");
421
plaintext_length = -1;
196
gpgme_data_seek(dh_plain, (off_t) 0, SEEK_SET);
427
plaintext_capacity = incbuffer(plaintext,
428
(size_t)plaintext_length,
430
if(plaintext_capacity == 0){
431
perror_plus("incbuffer");
432
plaintext_length = -1;
200
if (new_packet_length + BUFFER_SIZE > new_packet_capacity){
201
*new_packet = realloc(*new_packet,
202
(unsigned int)new_packet_capacity
204
if (*new_packet == NULL){
208
new_packet_capacity += BUFFER_SIZE;
436
ret = gpgme_data_read(dh_plain, *plaintext + plaintext_length,
211
ret = gpgme_data_read(dh_plain, *new_packet + new_packet_length,
438
213
/* Print the data, if any */
444
perror_plus("gpgme_data_read");
445
plaintext_length = -1;
448
plaintext_length += ret;
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");
461
/* Delete the GPGME cryptotext data buffer */
462
gpgme_data_release(dh_crypto);
218
perror("gpgme_data_read");
221
new_packet_length += ret;
224
/* FIXME: check characters before printing to screen so to not print
225
terminal control characters */
227
/* fprintf(stderr, "decrypted password is: "); */
228
/* fwrite(*new_packet, 1, new_packet_length, stderr); */
229
/* fprintf(stderr, "\n"); */
464
232
/* Delete the GPGME plaintext data buffer */
465
233
gpgme_data_release(dh_plain);
466
return plaintext_length;
234
return new_packet_length;
469
static const char * safer_gnutls_strerror(int value){
470
const char *ret = gnutls_strerror(value); /* Spurious warning from
471
-Wunreachable-code */
237
static const char * safer_gnutls_strerror (int value) {
238
const char *ret = gnutls_strerror (value);
473
240
ret = "(unknown)";
477
/* GnuTLS log function callback */
478
static void debuggnutls(__attribute__((unused)) int level,
480
fprintf_plus(stderr, "GnuTLS: %s", string);
244
void debuggnutls(__attribute__((unused)) int level,
246
fprintf(stderr, "%s", string);
483
static int init_gnutls_global(const char *pubkeyfilename,
484
const char *seckeyfilename){
249
int initgnutls(encrypted_session *es){
488
fprintf_plus(stderr, "Initializing GnuTLS\n");
254
fprintf(stderr, "Initializing GnuTLS\n");
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));
257
if ((ret = gnutls_global_init ())
258
!= GNUTLS_E_SUCCESS) {
259
fprintf (stderr, "global_init: %s\n", safer_gnutls_strerror(ret));
499
/* "Use a log level over 10 to enable all debugging options."
502
264
gnutls_global_set_log_level(11);
503
265
gnutls_global_set_log_function(debuggnutls);
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();
268
/* openpgp credentials */
269
if ((ret = gnutls_certificate_allocate_credentials (&es->cred))
270
!= GNUTLS_E_SUCCESS) {
271
fprintf (stderr, "memory error: %s\n",
272
safer_gnutls_strerror(ret));
516
fprintf_plus(stderr, "Attempting to use OpenPGP public key %s and"
517
" secret key %s as GnuTLS credentials\n",
277
fprintf(stderr, "Attempting to use OpenPGP certificate %s"
278
" and keyfile %s as GnuTLS credentials\n", CERTFILE,
522
282
ret = gnutls_certificate_set_openpgp_key_file
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);
283
(es->cred, CERTFILE, KEYFILE, GNUTLS_OPENPGP_FMT_BASE64);
284
if (ret != GNUTLS_E_SUCCESS) {
286
(stderr, "Error[%d] while reading the OpenPGP key pair ('%s',"
288
ret, CERTFILE, KEYFILE);
289
fprintf(stdout, "The Error is: %s\n",
290
safer_gnutls_strerror(ret));
294
//GnuTLS server initialization
295
if ((ret = gnutls_dh_params_init (&es->dh_params))
296
!= GNUTLS_E_SUCCESS) {
297
fprintf (stderr, "Error in dh parameter initialization: %s\n",
298
safer_gnutls_strerror(ret));
302
if ((ret = gnutls_dh_params_generate2 (es->dh_params, DH_BITS))
303
!= GNUTLS_E_SUCCESS) {
304
fprintf (stderr, "Error in prime generation: %s\n",
305
safer_gnutls_strerror(ret));
309
gnutls_certificate_set_dh_params (es->cred, es->dh_params);
311
// GnuTLS session creation
312
if ((ret = gnutls_init (&es->session, GNUTLS_SERVER))
313
!= GNUTLS_E_SUCCESS){
314
fprintf(stderr, "Error in GnuTLS session initialization: %s\n",
315
safer_gnutls_strerror(ret));
318
if ((ret = gnutls_priority_set_direct (es->session, "NORMAL", &err))
319
!= GNUTLS_E_SUCCESS) {
320
fprintf(stderr, "Syntax error at: %s\n", err);
321
fprintf(stderr, "GnuTLS error: %s\n",
322
safer_gnutls_strerror(ret));
326
if ((ret = gnutls_credentials_set
327
(es->session, GNUTLS_CRD_CERTIFICATE, es->cred))
328
!= GNUTLS_E_SUCCESS) {
329
fprintf(stderr, "Error setting a credentials set: %s\n",
330
safer_gnutls_strerror(ret));
609
334
/* ignore client certificate if any. */
610
gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);
335
gnutls_certificate_server_set_request (es->session,
612
gnutls_dh_set_prime_bits(*session, mc.dh_bits);
338
gnutls_dh_set_prime_bits (es->session, DH_BITS);
617
/* Avahi log function callback */
618
static void empty_log(__attribute__((unused)) AvahiLogLevel level,
619
__attribute__((unused)) const char *txt){}
343
void empty_log(__attribute__((unused)) AvahiLogLevel level,
344
__attribute__((unused)) const char *txt){}
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;
346
int start_mandos_communication(const char *ip, uint16_t port,
347
unsigned int if_index){
349
struct sockaddr_in6 to;
350
encrypted_session es;
631
351
char *buffer = NULL;
632
char *decrypted_buffer = NULL;
352
char *decrypted_buffer;
633
353
size_t buffer_length = 0;
634
354
size_t buffer_capacity = 0;
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
ssize_t decrypted_buffer_size;
358
char interface[IF_NAMESIZE];
361
fprintf(stderr, "Setting up a tcp connection to %s\n", ip);
364
tcp_sd = socket(PF_INET6, SOCK_STREAM, 0);
370
if(if_indextoname(if_index, interface) == NULL){
372
perror("if_indextoname");
378
fprintf(stderr, "Binding to interface %s\n", interface);
381
memset(&to,0,sizeof(to)); /* Spurious warning */
382
to.sin6_family = AF_INET6;
383
ret = inet_pton(AF_INET6, ip, &to.sin6_addr);
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,
389
fprintf(stderr, "Bad address: %s\n", ip);
392
to.sin6_port = htons(port); /* Spurious warning */
394
to.sin6_scope_id = (uint32_t)if_index;
397
fprintf(stderr, "Connection to: %s\n", ip);
400
ret = connect(tcp_sd, (struct sockaddr *) &to, sizeof(to));
406
ret = initgnutls (&es);
412
gnutls_transport_set_ptr (es.session,
413
(gnutls_transport_ptr_t) tcp_sd);
416
fprintf(stderr, "Establishing TLS session with %s\n", ip);
419
ret = gnutls_handshake (es.session);
421
if (ret != GNUTLS_E_SUCCESS){
422
fprintf(stderr, "\n*** Handshake failed ***\n");
428
//Retrieve OpenPGP packet that contains the wanted password
431
fprintf(stderr, "Retrieving pgp encrypted password from %s\n",
436
if (buffer_length + BUFFER_SIZE > buffer_capacity){
437
buffer = realloc(buffer, buffer_capacity + BUFFER_SIZE);
442
buffer_capacity += BUFFER_SIZE;
445
ret = gnutls_record_recv
446
(es.session, buffer+buffer_length, BUFFER_SIZE);
889
452
case GNUTLS_E_INTERRUPTED:
890
453
case GNUTLS_E_AGAIN:
892
455
case GNUTLS_E_REHANDSHAKE:
894
ret = gnutls_handshake(session);
900
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
902
fprintf_plus(stderr, "*** GnuTLS Re-handshake failed "
456
ret = gnutls_handshake (es.session);
458
fprintf(stderr, "\n*** Handshake failed ***\n");
910
fprintf_plus(stderr, "Unknown error while reading data from"
911
" encrypted session with Mandos server\n");
912
gnutls_bye(session, GNUTLS_SHUT_RDWR);
465
fprintf(stderr, "Unknown error while reading data from"
466
" encrypted session with mandos server\n");
468
gnutls_bye (es.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,
472
buffer_length += (size_t) ret;
476
if (buffer_length > 0){
477
decrypted_buffer_size = pgp_packet_decrypt(buffer,
481
if (decrypted_buffer_size >= 0){
482
while(written < decrypted_buffer_size){
483
ret = (int)fwrite (decrypted_buffer + written, 1,
484
(size_t)decrypted_buffer_size - written,
954
486
if(ret == 0 and ferror(stdout)){
957
fprintf_plus(stderr, "Error writing encrypted data: %s\n",
488
fprintf(stderr, "Error writing encrypted data: %s\n",
963
494
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);
496
free(decrypted_buffer);
505
fprintf(stderr, "Closing TLS session\n");
509
gnutls_bye (es.session, GNUTLS_SHUT_RDWR);
512
gnutls_deinit (es.session);
513
gnutls_certificate_free_credentials (es.cred);
514
gnutls_global_deinit ();
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){
518
static AvahiSimplePoll *simple_poll = NULL;
519
static AvahiServer *server = NULL;
521
static void resolve_callback(
522
AvahiSServiceResolver *r,
523
AvahiIfIndex interface,
524
AVAHI_GCC_UNUSED AvahiProtocol protocol,
525
AvahiResolverEvent event,
529
const char *host_name,
530
const AvahiAddress *address,
532
AVAHI_GCC_UNUSED AvahiStringList *txt,
533
AVAHI_GCC_UNUSED AvahiLookupResultFlags flags,
534
AVAHI_GCC_UNUSED void* userdata) {
536
assert(r); /* Spurious warning */
1011
538
/* Called whenever a service has been resolved successfully or
1020
543
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)));
544
fprintf(stderr, "(Resolver) Failed to resolve service '%s' of"
545
" type '%s' in domain '%s': %s\n", name, type, domain,
546
avahi_strerror(avahi_server_errno(server)));
1027
549
case AVAHI_RESOLVER_FOUND:
1029
551
char ip[AVAHI_ADDRESS_STR_MAX];
1030
552
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);
554
fprintf(stderr, "Mandos server found on %s (%s) on port %d\n",
555
host_name, ip, port);
1036
int ret = start_mandos_communication(ip, port, interface,
1037
avahi_proto_to_af(proto));
1039
avahi_simple_poll_quit(mc.simple_poll);
557
int ret = start_mandos_communication(ip, port,
558
(unsigned int) interface);
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
566
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){
1567
struct ifreq network;
1568
AvahiIfIndex if_index = (AvahiIfIndex)if_nametoindex(interface);
1570
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
1571
return EX_UNAVAILABLE;
1578
/* Re-raise priviliges */
1582
/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO
1583
messages about the network interface to mess up the prompt */
1584
ret = klogctl(8, NULL, 5);
1585
bool restore_loglevel = true;
1587
restore_loglevel = false;
1588
perror_plus("klogctl");
1590
#endif /* __linux__ */
1592
sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1594
perror_plus("socket");
1596
if(restore_loglevel){
1597
ret = klogctl(7, NULL, 0);
1599
perror_plus("klogctl");
1602
#endif /* __linux__ */
1603
/* Lower privileges */
1608
strcpy(network.ifr_name, interface);
1609
ret = ioctl(sd, SIOCGIFFLAGS, &network);
1611
perror_plus("ioctl SIOCGIFFLAGS");
1613
if(restore_loglevel){
1614
ret = klogctl(7, NULL, 0);
1616
perror_plus("klogctl");
1619
#endif /* __linux__ */
1620
/* Lower privileges */
1624
if((network.ifr_flags & IFF_UP) == 0){
1625
network.ifr_flags |= IFF_UP;
1626
ret = ioctl(sd, SIOCSIFFLAGS, &network);
1628
perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");
1630
if(restore_loglevel){
1631
ret = klogctl(7, NULL, 0);
1633
perror_plus("klogctl");
1636
#endif /* __linux__ */
1637
/* Lower privileges */
1642
/* Sleep checking until interface is running.
1643
Check every 0.25s, up to total time of delay */
1644
for(int i=0; i < delay * 4; i++){
1645
ret = ioctl(sd, SIOCGIFFLAGS, &network);
1647
perror_plus("ioctl SIOCGIFFLAGS");
1648
} else if(network.ifr_flags & IFF_RUNNING){
1651
struct timespec sleeptime = { .tv_nsec = 250000000 };
1652
ret = nanosleep(&sleeptime, NULL);
1653
if(ret == -1 and errno != EINTR){
1654
perror_plus("nanosleep");
1657
/* Close the socket */
1658
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1660
perror_plus("close");
1663
if(restore_loglevel){
1664
/* Restores kernel loglevel to default */
1665
ret = klogctl(7, NULL, 0);
1667
perror_plus("klogctl");
1670
#endif /* __linux__ */
1671
/* Lower privileges */
1676
int main(int argc, char *argv[]){
1677
AvahiSServiceBrowser *sb = NULL;
1682
int exitcode = EXIT_SUCCESS;
1683
const char *interface = "";
1684
struct ifreq network;
1686
bool take_down_interface = false;
1687
char tempdir[] = "/tmp/mandosXXXXXX";
1688
bool tempdir_created = false;
1689
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
1690
const char *seckey = PATHDIR "/" SECKEY;
1691
const char *pubkey = PATHDIR "/" PUBKEY;
1693
bool gnutls_initialized = false;
1694
bool gpgme_initialized = false;
1696
double retry_interval = 10; /* 10s between trying a server and
1697
retrying the same server again */
1699
struct sigaction old_sigterm_action = { .sa_handler = SIG_DFL };
1700
struct sigaction sigterm_action = { .sa_handler = handle_sigterm };
1705
/* Lower any group privileges we might have, just to be safe */
1709
perror_plus("setgid");
1712
/* Lower user privileges (temporarily) */
1716
perror_plus("seteuid");
1724
struct argp_option options[] = {
1725
{ .name = "debug", .key = 128,
1726
.doc = "Debug mode", .group = 3 },
1727
{ .name = "connect", .key = 'c',
1728
.arg = "ADDRESS:PORT",
1729
.doc = "Connect directly to a specific Mandos server",
1731
{ .name = "interface", .key = 'i',
1733
.doc = "Network interface that will be used to search for"
1736
{ .name = "seckey", .key = 's',
1738
.doc = "OpenPGP secret key file base name",
1740
{ .name = "pubkey", .key = 'p',
1742
.doc = "OpenPGP public key file base name",
1744
{ .name = "dh-bits", .key = 129,
1746
.doc = "Bit length of the prime number used in the"
1747
" Diffie-Hellman key exchange",
1749
{ .name = "priority", .key = 130,
1751
.doc = "GnuTLS priority string for the TLS handshake",
1753
{ .name = "delay", .key = 131,
1755
.doc = "Maximum delay to wait for interface startup",
1757
{ .name = "retry", .key = 132,
1759
.doc = "Retry interval used when denied by the Mandos server",
1761
{ .name = "network-hook-dir", .key = 133,
1763
.doc = "Directory where network hooks are located",
1766
* These reproduce what we would get without ARGP_NO_HELP
1768
{ .name = "help", .key = '?',
1769
.doc = "Give this help list", .group = -1 },
1770
{ .name = "usage", .key = -3,
1771
.doc = "Give a short usage message", .group = -1 },
1772
{ .name = "version", .key = 'V',
1773
.doc = "Print program version", .group = -1 },
1777
error_t parse_opt(int key, char *arg,
1778
struct argp_state *state){
1781
case 128: /* --debug */
1784
case 'c': /* --connect */
1787
case 'i': /* --interface */
1790
case 's': /* --seckey */
1793
case 'p': /* --pubkey */
1796
case 129: /* --dh-bits */
1798
tmpmax = strtoimax(arg, &tmp, 10);
1799
if(errno != 0 or tmp == arg or *tmp != '\0'
1800
or tmpmax != (typeof(mc.dh_bits))tmpmax){
1801
argp_error(state, "Bad number of DH bits");
1803
mc.dh_bits = (typeof(mc.dh_bits))tmpmax;
1805
case 130: /* --priority */
1808
case 131: /* --delay */
1810
delay = strtof(arg, &tmp);
1811
if(errno != 0 or tmp == arg or *tmp != '\0'){
1812
argp_error(state, "Bad delay");
1814
case 132: /* --retry */
1816
retry_interval = strtod(arg, &tmp);
1817
if(errno != 0 or tmp == arg or *tmp != '\0'
1818
or (retry_interval * 1000) > INT_MAX
1819
or retry_interval < 0){
1820
argp_error(state, "Bad retry interval");
1823
case 133: /* --network-hook-dir */
1827
* These reproduce what we would get without ARGP_NO_HELP
1829
case '?': /* --help */
1830
argp_state_help(state, state->out_stream,
1831
(ARGP_HELP_STD_HELP | ARGP_HELP_EXIT_ERR)
1832
& ~(unsigned int)ARGP_HELP_EXIT_OK);
1833
case -3: /* --usage */
1834
argp_state_help(state, state->out_stream,
1835
ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);
1836
case 'V': /* --version */
1837
fprintf_plus(state->out_stream, "%s\n", argp_program_version);
1838
exit(argp_err_exit_status);
1841
return ARGP_ERR_UNKNOWN;
1846
struct argp argp = { .options = options, .parser = parse_opt,
1848
.doc = "Mandos client -- Get and decrypt"
1849
" passwords from a Mandos server" };
1850
ret = argp_parse(&argp, argc, argv,
1851
ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);
569
static void browse_callback(
570
AvahiSServiceBrowser *b,
571
AvahiIfIndex interface,
572
AvahiProtocol protocol,
573
AvahiBrowserEvent event,
577
AVAHI_GCC_UNUSED AvahiLookupResultFlags flags,
580
AvahiServer *s = userdata;
581
assert(b); /* Spurious warning */
583
/* Called whenever a new services becomes available on the LAN or
584
is removed from the LAN */
1858
perror_plus("argp_parse");
1859
exitcode = EX_OSERR;
1862
exitcode = EX_USAGE;
1868
/* Work around Debian bug #633582:
1869
<http://bugs.debian.org/633582> */
1871
/* Re-raise priviliges */
1872
if(raise_privileges() == 0){
1875
if(strcmp(seckey, PATHDIR "/" SECKEY) == 0){
1876
int seckey_fd = open(seckey, O_RDONLY);
1877
if(seckey_fd == -1){
1878
perror_plus("open");
1880
ret = (int)TEMP_FAILURE_RETRY(fstat(seckey_fd, &st));
1882
perror_plus("fstat");
1884
if(S_ISREG(st.st_mode)
1885
and st.st_uid == 0 and st.st_gid == 0){
1886
ret = fchown(seckey_fd, uid, gid);
1888
perror_plus("fchown");
1892
TEMP_FAILURE_RETRY(close(seckey_fd));
1896
if(strcmp(pubkey, PATHDIR "/" PUBKEY) == 0){
1897
int pubkey_fd = open(pubkey, O_RDONLY);
1898
if(pubkey_fd == -1){
1899
perror_plus("open");
1901
ret = (int)TEMP_FAILURE_RETRY(fstat(pubkey_fd, &st));
1903
perror_plus("fstat");
1905
if(S_ISREG(st.st_mode)
1906
and st.st_uid == 0 and st.st_gid == 0){
1907
ret = fchown(pubkey_fd, uid, gid);
1909
perror_plus("fchown");
1913
TEMP_FAILURE_RETRY(close(pubkey_fd));
1917
/* Lower privileges */
1921
perror_plus("seteuid");
1926
/* Run network hooks */
1927
if(not run_network_hooks("start", interface, delay)){
1932
avahi_set_log_function(empty_log);
1935
if(interface[0] == '\0'){
1936
struct dirent **direntries;
1937
/* First look for interfaces that are up */
1938
ret = scandir(sys_class_net, &direntries, up_interface,
1941
/* No up interfaces, look for any good interfaces */
1943
ret = scandir(sys_class_net, &direntries, good_interface,
1947
/* Pick the first interface returned */
1948
interface = strdup(direntries[0]->d_name);
1950
fprintf_plus(stderr, "Using interface \"%s\"\n", interface);
1952
if(interface == NULL){
1953
perror_plus("malloc");
1955
exitcode = EXIT_FAILURE;
1961
fprintf_plus(stderr, "Could not find a network interface\n");
1962
exitcode = EXIT_FAILURE;
1967
/* Initialize Avahi early so avahi_simple_poll_quit() can be called
1968
from the signal handler */
1969
/* Initialize the pseudo-RNG for Avahi */
1970
srand((unsigned int) time(NULL));
1971
mc.simple_poll = avahi_simple_poll_new();
1972
if(mc.simple_poll == NULL){
1973
fprintf_plus(stderr,
1974
"Avahi: Failed to create simple poll object.\n");
1975
exitcode = EX_UNAVAILABLE;
1979
sigemptyset(&sigterm_action.sa_mask);
1980
ret = sigaddset(&sigterm_action.sa_mask, SIGINT);
1982
perror_plus("sigaddset");
1983
exitcode = EX_OSERR;
1986
ret = sigaddset(&sigterm_action.sa_mask, SIGHUP);
1988
perror_plus("sigaddset");
1989
exitcode = EX_OSERR;
1992
ret = sigaddset(&sigterm_action.sa_mask, SIGTERM);
1994
perror_plus("sigaddset");
1995
exitcode = EX_OSERR;
1998
/* Need to check if the handler is SIG_IGN before handling:
1999
| [[info:libc:Initial Signal Actions]] |
2000
| [[info:libc:Basic Signal Handling]] |
2002
ret = sigaction(SIGINT, NULL, &old_sigterm_action);
2004
perror_plus("sigaction");
2007
if(old_sigterm_action.sa_handler != SIG_IGN){
2008
ret = sigaction(SIGINT, &sigterm_action, NULL);
2010
perror_plus("sigaction");
2011
exitcode = EX_OSERR;
2015
ret = sigaction(SIGHUP, NULL, &old_sigterm_action);
2017
perror_plus("sigaction");
2020
if(old_sigterm_action.sa_handler != SIG_IGN){
2021
ret = sigaction(SIGHUP, &sigterm_action, NULL);
2023
perror_plus("sigaction");
2024
exitcode = EX_OSERR;
2028
ret = sigaction(SIGTERM, NULL, &old_sigterm_action);
2030
perror_plus("sigaction");
2033
if(old_sigterm_action.sa_handler != SIG_IGN){
2034
ret = sigaction(SIGTERM, &sigterm_action, NULL);
2036
perror_plus("sigaction");
2037
exitcode = EX_OSERR;
2042
/* If the interface is down, bring it up */
2043
if((interface[0] != '\0') and (strcmp(interface, "none") != 0)){
2044
ret = bring_up_interface(interface, delay);
2047
perror_plus("Failed to bring up interface");
2055
ret = init_gnutls_global(pubkey, seckey);
2057
fprintf_plus(stderr, "init_gnutls_global failed\n");
2058
exitcode = EX_UNAVAILABLE;
2061
gnutls_initialized = true;
2068
if(mkdtemp(tempdir) == NULL){
2069
perror_plus("mkdtemp");
2072
tempdir_created = true;
2078
if(not init_gpgme(pubkey, seckey, tempdir)){
2079
fprintf_plus(stderr, "init_gpgme failed\n");
2080
exitcode = EX_UNAVAILABLE;
2083
gpgme_initialized = true;
2090
if(connect_to != NULL){
2091
/* Connect directly, do not use Zeroconf */
2092
/* (Mainly meant for debugging) */
2093
char *address = strrchr(connect_to, ':');
2095
if(address == NULL){
2096
fprintf_plus(stderr, "No colon in address\n");
2097
exitcode = EX_USAGE;
2107
tmpmax = strtoimax(address+1, &tmp, 10);
2108
if(errno != 0 or tmp == address+1 or *tmp != '\0'
2109
or tmpmax != (uint16_t)tmpmax){
2110
fprintf_plus(stderr, "Bad port number\n");
2111
exitcode = EX_USAGE;
2119
port = (uint16_t)tmpmax;
2121
/* Colon in address indicates IPv6 */
2123
if(strchr(connect_to, ':') != NULL){
2125
/* Accept [] around IPv6 address - see RFC 5952 */
2126
if(connect_to[0] == '[' and address[-1] == ']')
2134
address = connect_to;
2140
while(not quit_now){
2141
ret = start_mandos_communication(address, port, if_index, af);
2142
if(quit_now or ret == 0){
2146
fprintf_plus(stderr, "Retrying in %d seconds\n",
2147
(int)retry_interval);
2149
sleep((int)retry_interval);
2153
exitcode = EXIT_SUCCESS;
588
case AVAHI_BROWSER_FAILURE:
590
fprintf(stderr, "(Browser) %s\n",
591
avahi_strerror(avahi_server_errno(server)));
592
avahi_simple_poll_quit(simple_poll);
595
case AVAHI_BROWSER_NEW:
596
/* We ignore the returned resolver object. In the callback
597
function we free it. If the server is terminated before
598
the callback function is called the server will free
599
the resolver for us. */
601
if (!(avahi_s_service_resolver_new(s, interface, protocol, name,
603
AVAHI_PROTO_INET6, 0,
604
resolve_callback, s)))
605
fprintf(stderr, "Failed to resolve service '%s': %s\n", name,
606
avahi_strerror(avahi_server_errno(s)));
609
case AVAHI_BROWSER_REMOVE:
612
case AVAHI_BROWSER_ALL_FOR_NOW:
613
case AVAHI_BROWSER_CACHE_EXHAUSTED:
618
int main(AVAHI_GCC_UNUSED int argc, AVAHI_GCC_UNUSED char*argv[]) {
2164
619
AvahiServerConfig config;
2165
/* Do not publish any local Zeroconf records */
620
AvahiSServiceBrowser *sb = NULL;
623
int returncode = EXIT_SUCCESS;
624
const char *interface = "eth0";
627
static struct option long_options[] = {
628
{"debug", no_argument, (int *)&debug, 1},
629
{"interface", required_argument, 0, 'i'},
632
int option_index = 0;
633
ret = getopt_long (argc, argv, "i:", long_options,
652
avahi_set_log_function(empty_log);
655
/* Initialize the psuedo-RNG */
656
srand((unsigned int) time(NULL));
658
/* Allocate main loop object */
659
if (!(simple_poll = avahi_simple_poll_new())) {
660
fprintf(stderr, "Failed to create simple poll object.\n");
665
/* Do not publish any local records */
2166
666
avahi_server_config_init(&config);
2167
667
config.publish_hinfo = 0;
2168
668
config.publish_addresses = 0;
2169
669
config.publish_workstation = 0;
2170
670
config.publish_domain = 0;
2172
672
/* Allocate a new server */
2173
mc.server = avahi_server_new(avahi_simple_poll_get
2174
(mc.simple_poll), &config, NULL,
2177
/* Free the Avahi configuration data */
673
server = avahi_server_new(avahi_simple_poll_get(simple_poll),
674
&config, NULL, NULL, &error);
676
/* Free the configuration data */
2178
677
avahi_server_config_free(&config);
2181
/* Check if creating the Avahi server object succeeded */
2182
if(mc.server == NULL){
2183
fprintf_plus(stderr, "Failed to create Avahi server: %s\n",
2184
avahi_strerror(error));
2185
exitcode = EX_UNAVAILABLE;
2193
/* Create the Avahi service browser */
2194
sb = avahi_s_service_browser_new(mc.server, if_index,
2195
AVAHI_PROTO_UNSPEC, "_mandos._tcp",
2196
NULL, 0, browse_callback, NULL);
2198
fprintf_plus(stderr, "Failed to create service browser: %s\n",
2199
avahi_strerror(avahi_server_errno(mc.server)));
2200
exitcode = EX_UNAVAILABLE;
2208
/* Run the main loop */
2211
fprintf_plus(stderr, "Starting Avahi loop search\n");
2214
ret = avahi_loop_with_timeout(mc.simple_poll,
2215
(int)(retry_interval * 1000));
2217
fprintf_plus(stderr, "avahi_loop_with_timeout exited %s\n",
2218
(ret == 0) ? "successfully" : "with error");
2224
fprintf_plus(stderr, "%s exiting\n", argv[0]);
2227
/* Cleanup things */
2229
avahi_s_service_browser_free(sb);
2231
if(mc.server != NULL)
2232
avahi_server_free(mc.server);
2234
if(mc.simple_poll != NULL)
2235
avahi_simple_poll_free(mc.simple_poll);
2237
if(gnutls_initialized){
2238
gnutls_certificate_free_credentials(mc.cred);
2239
gnutls_global_deinit();
2240
gnutls_dh_params_deinit(mc.dh_params);
2243
if(gpgme_initialized){
2244
gpgme_release(mc.ctx);
2247
/* Cleans up the circular linked list of Mandos servers the client
2249
if(mc.current_server != NULL){
2250
mc.current_server->prev->next = NULL;
2251
while(mc.current_server != NULL){
2252
server *next = mc.current_server->next;
2253
free(mc.current_server);
2254
mc.current_server = next;
2258
/* Run network hooks */
2259
run_network_hooks("stop", interface, delay);
2261
/* Re-raise priviliges */
2265
/* Take down the network interface */
2266
if(take_down_interface and geteuid() == 0){
2267
ret = ioctl(sd, SIOCGIFFLAGS, &network);
2269
perror_plus("ioctl SIOCGIFFLAGS");
2270
} else if(network.ifr_flags & IFF_UP){
2271
network.ifr_flags &= ~(short)IFF_UP; /* clear flag */
2272
ret = ioctl(sd, SIOCSIFFLAGS, &network);
2274
perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");
2277
ret = (int)TEMP_FAILURE_RETRY(close(sd));
2279
perror_plus("close");
2283
/* Lower privileges permanently */
2287
perror_plus("setuid");
2290
/* Removes the GPGME temp directory and all files inside */
2291
if(tempdir_created){
2292
struct dirent **direntries = NULL;
2293
struct dirent *direntry = NULL;
2294
int numentries = scandir(tempdir, &direntries, notdotentries,
2296
if (numentries > 0){
2297
for(int i = 0; i < numentries; i++){
2298
direntry = direntries[i];
2299
char *fullname = NULL;
2300
ret = asprintf(&fullname, "%s/%s", tempdir,
2303
perror_plus("asprintf");
2306
ret = remove(fullname);
2308
fprintf_plus(stderr, "remove(\"%s\"): %s\n", fullname,
2315
/* need to clean even if 0 because man page doesn't specify */
2317
if (numentries == -1){
2318
perror_plus("scandir");
2320
ret = rmdir(tempdir);
2321
if(ret == -1 and errno != ENOENT){
2322
perror_plus("rmdir");
2327
sigemptyset(&old_sigterm_action.sa_mask);
2328
old_sigterm_action.sa_handler = SIG_DFL;
2329
ret = (int)TEMP_FAILURE_RETRY(sigaction(signal_received,
2330
&old_sigterm_action,
2333
perror_plus("sigaction");
2336
ret = raise(signal_received);
2337
} while(ret != 0 and errno == EINTR);
2339
perror_plus("raise");
2342
TEMP_FAILURE_RETRY(pause());
679
/* Check if creating the server object succeeded */
681
fprintf(stderr, "Failed to create server: %s\n",
682
avahi_strerror(error));
683
returncode = EXIT_FAILURE;
687
/* Create the service browser */
688
sb = avahi_s_service_browser_new(server,
690
if_nametoindex(interface),
692
"_mandos._tcp", NULL, 0,
693
browse_callback, server);
695
fprintf(stderr, "Failed to create service browser: %s\n",
696
avahi_strerror(avahi_server_errno(server)));
697
returncode = EXIT_FAILURE;
701
/* Run the main loop */
704
fprintf(stderr, "Starting avahi loop search\n");
707
avahi_simple_poll_loop(simple_poll);
712
fprintf(stderr, "%s exiting\n", argv[0]);
717
avahi_s_service_browser_free(sb);
720
avahi_server_free(server);
723
avahi_simple_poll_free(simple_poll);