31
32
/* Needed by GPGME, specifically gpgme_data_seek() */
33
#ifndef _LARGEFILE_SOURCE
32
34
#define _LARGEFILE_SOURCE
36
#ifndef _FILE_OFFSET_BITS
33
37
#define _FILE_OFFSET_BITS 64
35
#define _GNU_SOURCE /* TEMP_FAILURE_RETRY() */
41
#include <net/if.h> /* if_nametoindex */
42
#include <sys/ioctl.h> // ioctl, ifreq, SIOCGIFFLAGS, IFF_UP, SIOCSIFFLAGS
43
#include <net/if.h> // ioctl, ifreq, SIOCGIFFLAGS, IFF_UP, SIOCSIFFLAGS
40
#define _GNU_SOURCE /* TEMP_FAILURE_RETRY(), asprintf() */
42
#include <stdio.h> /* fprintf(), stderr, fwrite(),
43
stdout, ferror(), remove() */
44
#include <stdint.h> /* uint16_t, uint32_t */
45
#include <stddef.h> /* NULL, size_t, ssize_t */
46
#include <stdlib.h> /* free(), EXIT_SUCCESS, EXIT_FAILURE,
47
srand(), strtof(), abort() */
48
#include <stdbool.h> /* bool, false, true */
49
#include <string.h> /* memset(), strcmp(), strlen(),
50
strerror(), asprintf(), strcpy() */
51
#include <sys/ioctl.h> /* ioctl */
52
#include <sys/types.h> /* socket(), inet_pton(), sockaddr,
53
sockaddr_in6, PF_INET6,
54
SOCK_STREAM, uid_t, gid_t, open(),
56
#include <sys/stat.h> /* open() */
57
#include <sys/socket.h> /* socket(), struct sockaddr_in6,
58
inet_pton(), connect() */
59
#include <fcntl.h> /* open() */
60
#include <dirent.h> /* opendir(), struct dirent, readdir()
62
#include <inttypes.h> /* PRIu16, PRIdMAX, intmax_t,
64
#include <assert.h> /* assert() */
65
#include <errno.h> /* perror(), errno */
66
#include <time.h> /* nanosleep(), time() */
67
#include <net/if.h> /* ioctl, ifreq, SIOCGIFFLAGS, IFF_UP,
68
SIOCSIFFLAGS, if_indextoname(),
69
if_nametoindex(), IF_NAMESIZE */
70
#include <netinet/in.h> /* IN6_IS_ADDR_LINKLOCAL,
71
INET_ADDRSTRLEN, INET6_ADDRSTRLEN
73
#include <unistd.h> /* close(), SEEK_SET, off_t, write(),
74
getuid(), getgid(), seteuid(),
76
#include <arpa/inet.h> /* inet_pton(), htons */
77
#include <iso646.h> /* not, or, and */
78
#include <argp.h> /* struct argp_option, error_t, struct
79
argp_state, struct argp,
80
argp_parse(), ARGP_KEY_ARG,
81
ARGP_KEY_END, ARGP_ERR_UNKNOWN */
82
#include <signal.h> /* sigemptyset(), sigaddset(),
83
sigaction(), SIGTERM, sig_atomic_t,
87
#include <sys/klog.h> /* klogctl() */
88
#endif /* __linux__ */
91
/* All Avahi types, constants and functions
45
94
#include <avahi-core/core.h>
46
95
#include <avahi-core/lookup.h>
47
96
#include <avahi-core/log.h>
101
162
return buffer_capacity;
104
static ssize_t pgp_packet_decrypt (char *packet, size_t packet_size,
106
const char *homedir){
107
gpgme_data_t dh_crypto, dh_plain;
168
static bool init_gpgme(const char *seckey,
169
const char *pubkey, const char *tempdir){
109
170
gpgme_error_t rc;
111
size_t new_packet_capacity = 0;
112
ssize_t new_packet_length = 0;
113
171
gpgme_engine_info_t engine_info;
116
fprintf(stderr, "Trying to decrypt OpenPGP packet\n");
175
* Helper function to insert pub and seckey to the engine keyring.
177
bool import_key(const char *filename){
180
gpgme_data_t pgp_data;
182
fd = (int)TEMP_FAILURE_RETRY(open(filename, O_RDONLY));
188
rc = gpgme_data_new_from_fd(&pgp_data, fd);
189
if(rc != GPG_ERR_NO_ERROR){
190
fprintf(stderr, "bad gpgme_data_new_from_fd: %s: %s\n",
191
gpgme_strsource(rc), gpgme_strerror(rc));
195
rc = gpgme_op_import(mc.ctx, pgp_data);
196
if(rc != GPG_ERR_NO_ERROR){
197
fprintf(stderr, "bad gpgme_op_import: %s: %s\n",
198
gpgme_strsource(rc), gpgme_strerror(rc));
202
ret = (int)TEMP_FAILURE_RETRY(close(fd));
206
gpgme_data_release(pgp_data);
211
fprintf(stderr, "Initializing GPGME\n");
120
215
gpgme_check_version(NULL);
121
216
rc = gpgme_engine_check_version(GPGME_PROTOCOL_OpenPGP);
122
if (rc != GPG_ERR_NO_ERROR){
217
if(rc != GPG_ERR_NO_ERROR){
123
218
fprintf(stderr, "bad gpgme_engine_check_version: %s: %s\n",
124
219
gpgme_strsource(rc), gpgme_strerror(rc));
128
/* Set GPGME home directory */
129
rc = gpgme_get_engine_info (&engine_info);
130
if (rc != GPG_ERR_NO_ERROR){
223
/* Set GPGME home directory for the OpenPGP engine only */
224
rc = gpgme_get_engine_info(&engine_info);
225
if(rc != GPG_ERR_NO_ERROR){
131
226
fprintf(stderr, "bad gpgme_get_engine_info: %s: %s\n",
132
227
gpgme_strsource(rc), gpgme_strerror(rc));
135
230
while(engine_info != NULL){
136
231
if(engine_info->protocol == GPGME_PROTOCOL_OpenPGP){
137
232
gpgme_set_engine_info(GPGME_PROTOCOL_OpenPGP,
138
engine_info->file_name, homedir);
233
engine_info->file_name, tempdir);
141
236
engine_info = engine_info->next;
143
238
if(engine_info == NULL){
144
fprintf(stderr, "Could not set home dir to %s\n", homedir);
148
/* Create new GPGME data buffer from packet buffer */
149
rc = gpgme_data_new_from_mem(&dh_crypto, packet, packet_size, 0);
150
if (rc != GPG_ERR_NO_ERROR){
239
fprintf(stderr, "Could not set GPGME home dir to %s\n", tempdir);
243
/* Create new GPGME "context" */
244
rc = gpgme_new(&(mc.ctx));
245
if(rc != GPG_ERR_NO_ERROR){
246
fprintf(stderr, "bad gpgme_new: %s: %s\n",
247
gpgme_strsource(rc), gpgme_strerror(rc));
251
if(not import_key(pubkey) or not import_key(seckey)){
259
* Decrypt OpenPGP data.
260
* Returns -1 on error
262
static ssize_t pgp_packet_decrypt(const char *cryptotext,
265
gpgme_data_t dh_crypto, dh_plain;
268
size_t plaintext_capacity = 0;
269
ssize_t plaintext_length = 0;
272
fprintf(stderr, "Trying to decrypt OpenPGP data\n");
275
/* Create new GPGME data buffer from memory cryptotext */
276
rc = gpgme_data_new_from_mem(&dh_crypto, cryptotext, crypto_size,
278
if(rc != GPG_ERR_NO_ERROR){
151
279
fprintf(stderr, "bad gpgme_data_new_from_mem: %s: %s\n",
152
280
gpgme_strsource(rc), gpgme_strerror(rc));
214
/* Delete the GPGME FILE pointer cryptotext data buffer */
215
gpgme_data_release(dh_crypto);
330
fprintf(stderr, "Decryption of OpenPGP data succeeded\n");
217
333
/* Seek back to the beginning of the GPGME plaintext data buffer */
218
if (gpgme_data_seek(dh_plain, (off_t) 0, SEEK_SET) == -1){
219
perror("pgpme_data_seek");
334
if(gpgme_data_seek(dh_plain, (off_t)0, SEEK_SET) == -1){
335
perror("gpgme_data_seek");
336
plaintext_length = -1;
224
new_packet_capacity = adjustbuffer(*new_packet, new_packet_length,
225
new_packet_capacity);
226
if (new_packet_capacity == 0){
227
perror("adjustbuffer");
230
new_packet_capacity += BUFFER_SIZE;
342
plaintext_capacity = incbuffer(plaintext,
343
(size_t)plaintext_length,
345
if(plaintext_capacity == 0){
347
plaintext_length = -1;
233
ret = gpgme_data_read(dh_plain, *new_packet + new_packet_length,
351
ret = gpgme_data_read(dh_plain, *plaintext + plaintext_length,
235
353
/* Print the data, if any */
240
359
perror("gpgme_data_read");
243
new_packet_length += ret;
246
/* FIXME: check characters before printing to screen so to not print
247
terminal control characters */
249
/* fprintf(stderr, "decrypted password is: "); */
250
/* fwrite(*new_packet, 1, new_packet_length, stderr); */
251
/* fprintf(stderr, "\n"); */
360
plaintext_length = -1;
363
plaintext_length += ret;
367
fprintf(stderr, "Decrypted password is: ");
368
for(ssize_t i = 0; i < plaintext_length; i++){
369
fprintf(stderr, "%02hhX ", (*plaintext)[i]);
371
fprintf(stderr, "\n");
376
/* Delete the GPGME cryptotext data buffer */
377
gpgme_data_release(dh_crypto);
254
379
/* Delete the GPGME plaintext data buffer */
255
380
gpgme_data_release(dh_plain);
256
return new_packet_length;
381
return plaintext_length;
259
static const char * safer_gnutls_strerror (int value) {
260
const char *ret = gnutls_strerror (value);
384
static const char * safer_gnutls_strerror(int value){
385
const char *ret = gnutls_strerror(value); /* Spurious warning from
386
-Wunreachable-code */
262
388
ret = "(unknown)";
392
/* GnuTLS log function callback */
266
393
static void debuggnutls(__attribute__((unused)) int level,
267
394
const char* string){
268
fprintf(stderr, "%s", string);
395
fprintf(stderr, "GnuTLS: %s", string);
271
static int initgnutls(mandos_context *mc){
398
static int init_gnutls_global(const char *pubkeyfilename,
399
const char *seckeyfilename){
276
403
fprintf(stderr, "Initializing GnuTLS\n");
279
if ((ret = gnutls_global_init ())
280
!= GNUTLS_E_SUCCESS) {
281
fprintf (stderr, "global_init: %s\n", safer_gnutls_strerror(ret));
406
ret = gnutls_global_init();
407
if(ret != GNUTLS_E_SUCCESS){
408
fprintf(stderr, "GnuTLS global_init: %s\n",
409
safer_gnutls_strerror(ret));
414
/* "Use a log level over 10 to enable all debugging options."
286
417
gnutls_global_set_log_level(11);
287
418
gnutls_global_set_log_function(debuggnutls);
290
/* openpgp credentials */
291
if ((ret = gnutls_certificate_allocate_credentials (&es->cred))
292
!= GNUTLS_E_SUCCESS) {
293
fprintf (stderr, "memory error: %s\n",
294
safer_gnutls_strerror(ret));
421
/* OpenPGP credentials */
422
gnutls_certificate_allocate_credentials(&mc.cred);
423
if(ret != GNUTLS_E_SUCCESS){
424
fprintf(stderr, "GnuTLS memory error: %s\n", /* Spurious warning
428
safer_gnutls_strerror(ret));
429
gnutls_global_deinit();
299
fprintf(stderr, "Attempting to use OpenPGP certificate %s"
300
" and keyfile %s as GnuTLS credentials\n", certfile,
434
fprintf(stderr, "Attempting to use OpenPGP public key %s and"
435
" secret key %s as GnuTLS credentials\n", pubkeyfilename,
304
439
ret = gnutls_certificate_set_openpgp_key_file
305
(es->cred, certfile, certkey, GNUTLS_OPENPGP_FMT_BASE64);
306
if (ret != GNUTLS_E_SUCCESS) {
308
(stderr, "Error[%d] while reading the OpenPGP key pair ('%s',"
310
ret, certfile, certkey);
311
fprintf(stdout, "The Error is: %s\n",
312
safer_gnutls_strerror(ret));
316
//GnuTLS server initialization
317
if ((ret = gnutls_dh_params_init (&es->dh_params))
318
!= GNUTLS_E_SUCCESS) {
319
fprintf (stderr, "Error in dh parameter initialization: %s\n",
320
safer_gnutls_strerror(ret));
324
if ((ret = gnutls_dh_params_generate2 (es->dh_params, DH_BITS))
325
!= GNUTLS_E_SUCCESS) {
326
fprintf (stderr, "Error in prime generation: %s\n",
327
safer_gnutls_strerror(ret));
331
gnutls_certificate_set_dh_params (es->cred, es->dh_params);
333
// GnuTLS session creation
334
if ((ret = gnutls_init (&es->session, GNUTLS_SERVER))
335
!= GNUTLS_E_SUCCESS){
440
(mc.cred, pubkeyfilename, seckeyfilename,
441
GNUTLS_OPENPGP_FMT_BASE64);
442
if(ret != GNUTLS_E_SUCCESS){
444
"Error[%d] while reading the OpenPGP key pair ('%s',"
445
" '%s')\n", ret, pubkeyfilename, seckeyfilename);
446
fprintf(stderr, "The GnuTLS error is: %s\n",
447
safer_gnutls_strerror(ret));
451
/* GnuTLS server initialization */
452
ret = gnutls_dh_params_init(&mc.dh_params);
453
if(ret != GNUTLS_E_SUCCESS){
454
fprintf(stderr, "Error in GnuTLS DH parameter initialization:"
455
" %s\n", safer_gnutls_strerror(ret));
458
ret = gnutls_dh_params_generate2(mc.dh_params, mc.dh_bits);
459
if(ret != GNUTLS_E_SUCCESS){
460
fprintf(stderr, "Error in GnuTLS prime generation: %s\n",
461
safer_gnutls_strerror(ret));
465
gnutls_certificate_set_dh_params(mc.cred, mc.dh_params);
471
gnutls_certificate_free_credentials(mc.cred);
472
gnutls_global_deinit();
473
gnutls_dh_params_deinit(mc.dh_params);
477
static int init_gnutls_session(gnutls_session_t *session){
479
/* GnuTLS session creation */
481
ret = gnutls_init(session, GNUTLS_SERVER);
485
} while(ret == GNUTLS_E_INTERRUPTED or ret == GNUTLS_E_AGAIN);
486
if(ret != GNUTLS_E_SUCCESS){
336
487
fprintf(stderr, "Error in GnuTLS session initialization: %s\n",
337
488
safer_gnutls_strerror(ret));
340
if ((ret = gnutls_priority_set_direct (es->session, mc->priority, &err))
341
!= GNUTLS_E_SUCCESS) {
342
fprintf(stderr, "Syntax error at: %s\n", err);
343
fprintf(stderr, "GnuTLS error: %s\n",
344
safer_gnutls_strerror(ret));
494
ret = gnutls_priority_set_direct(*session, mc.priority, &err);
496
gnutls_deinit(*session);
499
} while(ret == GNUTLS_E_INTERRUPTED or ret == GNUTLS_E_AGAIN);
500
if(ret != GNUTLS_E_SUCCESS){
501
fprintf(stderr, "Syntax error at: %s\n", err);
502
fprintf(stderr, "GnuTLS error: %s\n",
503
safer_gnutls_strerror(ret));
504
gnutls_deinit(*session);
348
if ((ret = gnutls_credentials_set
349
(es->session, GNUTLS_CRD_CERTIFICATE, es->cred))
350
!= GNUTLS_E_SUCCESS) {
351
fprintf(stderr, "Error setting a credentials set: %s\n",
510
ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,
513
gnutls_deinit(*session);
516
} while(ret == GNUTLS_E_INTERRUPTED or ret == GNUTLS_E_AGAIN);
517
if(ret != GNUTLS_E_SUCCESS){
518
fprintf(stderr, "Error setting GnuTLS credentials: %s\n",
352
519
safer_gnutls_strerror(ret));
520
gnutls_deinit(*session);
356
524
/* ignore client certificate if any. */
357
gnutls_certificate_server_set_request (es->session,
525
gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);
360
gnutls_dh_set_prime_bits (es->session, DH_BITS);
527
gnutls_dh_set_prime_bits(*session, mc.dh_bits);
532
/* Avahi log function callback */
365
533
static void empty_log(__attribute__((unused)) AvahiLogLevel level,
366
534
__attribute__((unused)) const char *txt){}
536
/* Called when a Mandos server is found */
368
537
static int start_mandos_communication(const char *ip, uint16_t port,
369
538
AvahiIfIndex if_index,
372
struct sockaddr_in6 to;
373
encrypted_session es;
540
int ret, tcp_sd = -1;
543
struct sockaddr_in in;
544
struct sockaddr_in6 in6;
374
546
char *buffer = NULL;
375
char *decrypted_buffer;
547
char *decrypted_buffer = NULL;
376
548
size_t buffer_length = 0;
377
549
size_t buffer_capacity = 0;
378
ssize_t decrypted_buffer_size;
381
char interface[IF_NAMESIZE];
552
gnutls_session_t session;
553
int pf; /* Protocol family */
567
fprintf(stderr, "Bad address family: %d\n", af);
571
ret = init_gnutls_session(&session);
384
fprintf(stderr, "Setting up a tcp connection to %s, port %d\n",
577
fprintf(stderr, "Setting up a TCP connection to %s, port %" PRIu16
388
tcp_sd = socket(PF_INET6, SOCK_STREAM, 0);
581
tcp_sd = socket(pf, SOCK_STREAM, 0);
390
583
perror("socket");
395
if(if_indextoname((unsigned int)if_index, interface) == NULL){
397
perror("if_indextoname");
402
fprintf(stderr, "Binding to interface %s\n", interface);
405
memset(&to,0,sizeof(to)); /* Spurious warning */
406
to.sin6_family = AF_INET6;
407
ret = inet_pton(AF_INET6, ip, &to.sin6_addr);
591
memset(&to, 0, sizeof(to));
593
to.in6.sin6_family = (sa_family_t)af;
594
ret = inet_pton(af, ip, &to.in6.sin6_addr);
596
to.in.sin_family = (sa_family_t)af;
597
ret = inet_pton(af, ip, &to.in.sin_addr);
409
600
perror("inet_pton");
413
604
fprintf(stderr, "Bad address: %s\n", ip);
416
to.sin6_port = htons(port); /* Spurious warning */
608
to.in6.sin6_port = htons(port); /* Spurious warnings from
610
-Wunreachable-code */
612
if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */
613
(&to.in6.sin6_addr)){ /* -Wstrict-aliasing=2 or lower and
615
if(if_index == AVAHI_IF_UNSPEC){
616
fprintf(stderr, "An IPv6 link-local address is incomplete"
617
" without a network interface\n");
620
/* Set the network interface number as scope */
621
to.in6.sin6_scope_id = (uint32_t)if_index;
624
to.in.sin_port = htons(port); /* Spurious warnings from
626
-Wunreachable-code */
418
to.sin6_scope_id = (uint32_t)if_index;
421
fprintf(stderr, "Connection to: %s, port %d\n", ip, port);
422
/* char addrstr[INET6_ADDRSTRLEN]; */
423
/* if(inet_ntop(to.sin6_family, &(to.sin6_addr), addrstr, */
424
/* sizeof(addrstr)) == NULL){ */
425
/* perror("inet_ntop"); */
427
/* fprintf(stderr, "Really connecting to: %s, port %d\n", */
428
/* addrstr, ntohs(to.sin6_port)); */
432
ret = connect(tcp_sd, (struct sockaddr *) &to, sizeof(to));
634
if(af == AF_INET6 and if_index != AVAHI_IF_UNSPEC){
635
char interface[IF_NAMESIZE];
636
if(if_indextoname((unsigned int)if_index, interface) == NULL){
637
perror("if_indextoname");
639
fprintf(stderr, "Connection to: %s%%%s, port %" PRIu16 "\n",
640
ip, interface, port);
643
fprintf(stderr, "Connection to: %s, port %" PRIu16 "\n", ip,
646
char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?
647
INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";
650
pcret = inet_ntop(af, &(to.in6.sin6_addr), addrstr,
653
pcret = inet_ntop(af, &(to.in.sin_addr), addrstr,
659
if(strcmp(addrstr, ip) != 0){
660
fprintf(stderr, "Canonical address form: %s\n", addrstr);
670
ret = connect(tcp_sd, &to.in6, sizeof(to));
672
ret = connect(tcp_sd, &to.in, sizeof(to)); /* IPv4 */
434
675
perror("connect");
438
char *out = mandos_protocol_version;
683
const char *out = mandos_protocol_version;
441
686
size_t out_size = strlen(out);
442
ret = TEMP_FAILURE_RETRY(write(tcp_sd, out + written,
687
ret = (int)TEMP_FAILURE_RETRY(write(tcp_sd, out + written,
443
688
out_size - written));
693
written += (size_t)ret;
450
694
if(written < out_size){
453
if (out == mandos_protocol_version){
697
if(out == mandos_protocol_version){
462
ret = initgnutls (&es);
468
gnutls_transport_set_ptr (es.session,
469
(gnutls_transport_ptr_t) tcp_sd);
472
711
fprintf(stderr, "Establishing TLS session with %s\n", ip);
475
ret = gnutls_handshake (es.session);
477
if (ret != GNUTLS_E_SUCCESS){
718
gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);
725
ret = gnutls_handshake(session);
729
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
731
if(ret != GNUTLS_E_SUCCESS){
479
fprintf(stderr, "\n*** Handshake failed ***\n");
733
fprintf(stderr, "*** GnuTLS Handshake failed ***\n");
486
//Retrieve OpenPGP packet that contains the wanted password
739
/* Read OpenPGP packet that contains the wanted password */
489
fprintf(stderr, "Retrieving pgp encrypted password from %s\n",
742
fprintf(stderr, "Retrieving OpenPGP encrypted password from %s\n",
494
buffer_capacity = adjustbuffer(buffer, buffer_length, buffer_capacity);
495
if (buffer_capacity == 0){
496
perror("adjustbuffer");
501
ret = gnutls_record_recv
502
(es.session, buffer+buffer_length, BUFFER_SIZE);
752
buffer_capacity = incbuffer(&buffer, buffer_length,
754
if(buffer_capacity == 0){
763
sret = gnutls_record_recv(session, buffer+buffer_length,
508
770
case GNUTLS_E_INTERRUPTED:
509
771
case GNUTLS_E_AGAIN:
511
773
case GNUTLS_E_REHANDSHAKE:
512
ret = gnutls_handshake (es.session);
514
fprintf(stderr, "\n*** Handshake failed ***\n");
775
ret = gnutls_handshake(session);
780
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
782
fprintf(stderr, "*** GnuTLS Re-handshake failed ***\n");
521
788
fprintf(stderr, "Unknown error while reading data from"
522
" encrypted session with mandos server\n");
524
gnutls_bye (es.session, GNUTLS_SHUT_RDWR);
789
" encrypted session with Mandos server\n");
790
gnutls_bye(session, GNUTLS_SHUT_RDWR);
528
buffer_length += (size_t) ret;
532
if (buffer_length > 0){
794
buffer_length += (size_t) sret;
799
fprintf(stderr, "Closing TLS session\n");
807
ret = gnutls_bye(session, GNUTLS_SHUT_RDWR);
811
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
813
if(buffer_length > 0){
814
ssize_t decrypted_buffer_size;
533
815
decrypted_buffer_size = pgp_packet_decrypt(buffer,
537
if (decrypted_buffer_size >= 0){
818
if(decrypted_buffer_size >= 0){
539
821
while(written < (size_t) decrypted_buffer_size){
540
ret = (int)fwrite (decrypted_buffer + written, 1,
541
(size_t)decrypted_buffer_size - written,
826
ret = (int)fwrite(decrypted_buffer + written, 1,
827
(size_t)decrypted_buffer_size - written,
543
829
if(ret == 0 and ferror(stdout)){
545
831
fprintf(stderr, "Error writing encrypted data: %s\n",
546
832
strerror(errno));
551
836
written += (size_t)ret;
553
free(decrypted_buffer);
562
fprintf(stderr, "Closing TLS session\n");
842
/* Shutdown procedure */
845
free(decrypted_buffer);
566
gnutls_bye (es.session, GNUTLS_SHUT_RDWR);
569
gnutls_deinit (es.session);
570
gnutls_certificate_free_credentials (es.cred);
571
gnutls_global_deinit ();
848
ret = (int)TEMP_FAILURE_RETRY(close(tcp_sd));
853
gnutls_deinit(session);
575
static void resolve_callback( AvahiSServiceResolver *r,
576
AvahiIfIndex interface,
577
AVAHI_GCC_UNUSED AvahiProtocol protocol,
578
AvahiResolverEvent event,
582
const char *host_name,
583
const AvahiAddress *address,
585
AVAHI_GCC_UNUSED AvahiStringList *txt,
586
AVAHI_GCC_UNUSED AvahiLookupResultFlags flags,
587
AVAHI_GCC_UNUSED void* userdata) {
588
mandos_context *mc = userdata;
589
assert(r); /* Spurious warning */
860
static void resolve_callback(AvahiSServiceResolver *r,
861
AvahiIfIndex interface,
863
AvahiResolverEvent event,
867
const char *host_name,
868
const AvahiAddress *address,
870
AVAHI_GCC_UNUSED AvahiStringList *txt,
871
AVAHI_GCC_UNUSED AvahiLookupResultFlags
873
AVAHI_GCC_UNUSED void* userdata){
591
876
/* Called whenever a service has been resolved successfully or
596
885
case AVAHI_RESOLVER_FAILURE:
597
fprintf(stderr, "(Resolver) Failed to resolve service '%s' of"
598
" type '%s' in domain '%s': %s\n", name, type, domain,
599
avahi_strerror(avahi_server_errno(mc->server)));
886
fprintf(stderr, "(Avahi Resolver) Failed to resolve service '%s'"
887
" of type '%s' in domain '%s': %s\n", name, type, domain,
888
avahi_strerror(avahi_server_errno(mc.server)));
602
891
case AVAHI_RESOLVER_FOUND:
604
893
char ip[AVAHI_ADDRESS_STR_MAX];
605
894
avahi_address_snprint(ip, sizeof(ip), address);
607
fprintf(stderr, "Mandos server \"%s\" found on %s (%s) on"
608
" port %d\n", name, host_name, ip, port);
896
fprintf(stderr, "Mandos server \"%s\" found on %s (%s, %"
897
PRIdMAX ") on port %" PRIu16 "\n", name, host_name,
898
ip, (intmax_t)interface, port);
610
int ret = start_mandos_communication(ip, port, interface, mc);
900
int ret = start_mandos_communication(ip, port, interface,
901
avahi_proto_to_af(proto));
903
avahi_simple_poll_quit(mc.simple_poll);
616
907
avahi_s_service_resolver_free(r);
619
static void browse_callback( AvahiSServiceBrowser *b,
620
AvahiIfIndex interface,
621
AvahiProtocol protocol,
622
AvahiBrowserEvent event,
626
AVAHI_GCC_UNUSED AvahiLookupResultFlags flags,
628
mandos_context *mc = userdata;
629
assert(b); /* Spurious warning */
910
static void browse_callback(AvahiSServiceBrowser *b,
911
AvahiIfIndex interface,
912
AvahiProtocol protocol,
913
AvahiBrowserEvent event,
917
AVAHI_GCC_UNUSED AvahiLookupResultFlags
919
AVAHI_GCC_UNUSED void* userdata){
631
922
/* Called whenever a new services becomes available on the LAN or
632
923
is removed from the LAN */
636
931
case AVAHI_BROWSER_FAILURE:
638
fprintf(stderr, "(Browser) %s\n",
639
avahi_strerror(avahi_server_errno(mc->server)));
640
avahi_simple_poll_quit(mc->simple_poll);
933
fprintf(stderr, "(Avahi browser) %s\n",
934
avahi_strerror(avahi_server_errno(mc.server)));
935
avahi_simple_poll_quit(mc.simple_poll);
643
938
case AVAHI_BROWSER_NEW:
644
/* We ignore the returned resolver object. In the callback
645
function we free it. If the server is terminated before
646
the callback function is called the server will free
647
the resolver for us. */
649
if (!(avahi_s_service_resolver_new(mc->server, interface, protocol, name,
651
AVAHI_PROTO_INET6, 0,
652
resolve_callback, mc)))
653
fprintf(stderr, "Failed to resolve service '%s': %s\n", name,
654
avahi_strerror(avahi_server_errno(s)));
939
/* We ignore the returned Avahi resolver object. In the callback
940
function we free it. If the Avahi server is terminated before
941
the callback function is called the Avahi server will free the
944
if(avahi_s_service_resolver_new(mc.server, interface, protocol,
945
name, type, domain, protocol, 0,
946
resolve_callback, NULL) == NULL)
947
fprintf(stderr, "Avahi: Failed to resolve service '%s': %s\n",
948
name, avahi_strerror(avahi_server_errno(mc.server)));
657
951
case AVAHI_BROWSER_REMOVE:
660
954
case AVAHI_BROWSER_ALL_FOR_NOW:
661
955
case AVAHI_BROWSER_CACHE_EXHAUSTED:
957
fprintf(stderr, "No Mandos server found, still searching...\n");
666
/* Combines file name and path and returns the malloced new
667
string. some sane checks could/should be added */
668
static const char *combinepath(const char *first, const char *second){
669
size_t f_len = strlen(first);
670
size_t s_len = strlen(second);
671
char *tmp = malloc(f_len + s_len + 2);
676
memcpy(tmp, first, f_len);
680
memcpy(tmp + f_len + 1, second, s_len);
682
tmp[f_len + 1 + s_len] = '\0';
963
/* stop main loop after sigterm has been called */
964
static void handle_sigterm(int sig){
969
signal_received = sig;
970
int old_errno = errno;
971
if(mc.simple_poll != NULL){
972
avahi_simple_poll_quit(mc.simple_poll);
687
int main(AVAHI_GCC_UNUSED int argc, AVAHI_GCC_UNUSED char*argv[]) {
688
AvahiServerConfig config;
689
AvahiSServiceBrowser *sb = NULL;
692
int returncode = EXIT_SUCCESS;
693
const char *interface = "eth0";
694
struct ifreq network;
696
char *connect_to = NULL;
697
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
698
mandos_context mc = { .simple_poll = NULL, .server = NULL,
699
.dh_bits = 2048, .priority = "SECURE256"};
977
int main(int argc, char *argv[]){
978
AvahiSServiceBrowser *sb = NULL;
983
int exitcode = EXIT_SUCCESS;
984
const char *interface = "eth0";
985
struct ifreq network;
987
bool take_down_interface = false;
990
char *connect_to = NULL;
991
char tempdir[] = "/tmp/mandosXXXXXX";
992
bool tempdir_created = false;
993
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
994
const char *seckey = PATHDIR "/" SECKEY;
995
const char *pubkey = PATHDIR "/" PUBKEY;
997
bool gnutls_initialized = false;
998
bool gpgme_initialized = false;
1001
struct sigaction old_sigterm_action = { .sa_handler = SIG_DFL };
1002
struct sigaction sigterm_action = { .sa_handler = handle_sigterm };
1007
/* Lower any group privileges we might have, just to be safe */
1014
/* Lower user privileges (temporarily) */
1026
struct argp_option options[] = {
1027
{ .name = "debug", .key = 128,
1028
.doc = "Debug mode", .group = 3 },
1029
{ .name = "connect", .key = 'c',
1030
.arg = "ADDRESS:PORT",
1031
.doc = "Connect directly to a specific Mandos server",
1033
{ .name = "interface", .key = 'i',
1035
.doc = "Network interface that will be used to search for"
1038
{ .name = "seckey", .key = 's',
1040
.doc = "OpenPGP secret key file base name",
1042
{ .name = "pubkey", .key = 'p',
1044
.doc = "OpenPGP public key file base name",
1046
{ .name = "dh-bits", .key = 129,
1048
.doc = "Bit length of the prime number used in the"
1049
" Diffie-Hellman key exchange",
1051
{ .name = "priority", .key = 130,
1053
.doc = "GnuTLS priority string for the TLS handshake",
1055
{ .name = "delay", .key = 131,
1057
.doc = "Maximum delay to wait for interface startup",
702
static struct option long_options[] = {
703
{"debug", no_argument, (int *)&debug, 1},
704
{"connect", required_argument, 0, 'C'},
705
{"interface", required_argument, 0, 'i'},
706
{"certdir", required_argument, 0, 'd'},
707
{"certkey", required_argument, 0, 'c'},
708
{"certfile", required_argument, 0, 'k'},
709
{"dh_bits", required_argument, 0, 'D'},
710
{"priority", required_argument, 0, 'p'},
713
int option_index = 0;
714
ret = getopt_long (argc, argv, "i:", long_options,
743
tmp = strtol(optarg, NULL, 10);
744
if (errno == ERANGE){
752
mc.priority = optarg;
1062
error_t parse_opt(int key, char *arg,
1063
struct argp_state *state){
1065
case 128: /* --debug */
1068
case 'c': /* --connect */
1071
case 'i': /* --interface */
1074
case 's': /* --seckey */
1077
case 'p': /* --pubkey */
1080
case 129: /* --dh-bits */
1082
tmpmax = strtoimax(arg, &tmp, 10);
1083
if(errno != 0 or tmp == arg or *tmp != '\0'
1084
or tmpmax != (typeof(mc.dh_bits))tmpmax){
1085
fprintf(stderr, "Bad number of DH bits\n");
1088
mc.dh_bits = (typeof(mc.dh_bits))tmpmax;
1090
case 130: /* --priority */
1093
case 131: /* --delay */
1095
delay = strtof(arg, &tmp);
1096
if(errno != 0 or tmp == arg or *tmp != '\0'){
1097
fprintf(stderr, "Bad delay\n");
1106
return ARGP_ERR_UNKNOWN;
759
certfile = combinepath(certdir, certfile);
760
if (certfile == NULL){
761
perror("combinepath");
762
returncode = EXIT_FAILURE;
766
certkey = combinepath(certdir, certkey);
767
if (certkey == NULL){
768
perror("combinepath");
769
returncode = EXIT_FAILURE;
1111
struct argp argp = { .options = options, .parser = parse_opt,
1113
.doc = "Mandos client -- Get and decrypt"
1114
" passwords from a Mandos server" };
1115
ret = argp_parse(&argp, argc, argv, 0, 0, NULL);
1116
if(ret == ARGP_ERR_UNKNOWN){
1117
fprintf(stderr, "Unknown error while parsing arguments\n");
1118
exitcode = EXIT_FAILURE;
1124
avahi_set_log_function(empty_log);
1127
/* Initialize Avahi early so avahi_simple_poll_quit() can be called
1128
from the signal handler */
1129
/* Initialize the pseudo-RNG for Avahi */
1130
srand((unsigned int) time(NULL));
1131
mc.simple_poll = avahi_simple_poll_new();
1132
if(mc.simple_poll == NULL){
1133
fprintf(stderr, "Avahi: Failed to create simple poll object.\n");
1134
exitcode = EXIT_FAILURE;
1138
sigemptyset(&sigterm_action.sa_mask);
1139
ret = sigaddset(&sigterm_action.sa_mask, SIGINT);
1141
perror("sigaddset");
1142
exitcode = EXIT_FAILURE;
1145
ret = sigaddset(&sigterm_action.sa_mask, SIGHUP);
1147
perror("sigaddset");
1148
exitcode = EXIT_FAILURE;
1151
ret = sigaddset(&sigterm_action.sa_mask, SIGTERM);
1153
perror("sigaddset");
1154
exitcode = EXIT_FAILURE;
1157
/* Need to check if the handler is SIG_IGN before handling:
1158
| [[info:libc:Initial Signal Actions]] |
1159
| [[info:libc:Basic Signal Handling]] |
1161
ret = sigaction(SIGINT, NULL, &old_sigterm_action);
1163
perror("sigaction");
1164
return EXIT_FAILURE;
1166
if(old_sigterm_action.sa_handler != SIG_IGN){
1167
ret = sigaction(SIGINT, &sigterm_action, NULL);
1169
perror("sigaction");
1170
exitcode = EXIT_FAILURE;
1174
ret = sigaction(SIGHUP, NULL, &old_sigterm_action);
1176
perror("sigaction");
1177
return EXIT_FAILURE;
1179
if(old_sigterm_action.sa_handler != SIG_IGN){
1180
ret = sigaction(SIGHUP, &sigterm_action, NULL);
1182
perror("sigaction");
1183
exitcode = EXIT_FAILURE;
1187
ret = sigaction(SIGTERM, NULL, &old_sigterm_action);
1189
perror("sigaction");
1190
return EXIT_FAILURE;
1192
if(old_sigterm_action.sa_handler != SIG_IGN){
1193
ret = sigaction(SIGTERM, &sigterm_action, NULL);
1195
perror("sigaction");
1196
exitcode = EXIT_FAILURE;
1201
/* If the interface is down, bring it up */
1202
if(interface[0] != '\0'){
773
1203
if_index = (AvahiIfIndex) if_nametoindex(interface);
774
1204
if(if_index == 0){
775
1205
fprintf(stderr, "No such interface: \"%s\"\n", interface);
779
if(connect_to != NULL){
780
/* Connect directly, do not use Zeroconf */
781
/* (Mainly meant for debugging) */
782
char *address = strrchr(connect_to, ':');
784
fprintf(stderr, "No colon in address\n");
788
uint16_t port = (uint16_t) strtol(address+1, NULL, 10);
790
perror("Bad port number");
794
address = connect_to;
795
ret = start_mandos_communication(address, port, if_index);
1206
exitcode = EXIT_FAILURE;
1214
/* Re-raise priviliges */
1222
/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO
1223
messages to mess up the prompt */
1224
ret = klogctl(8, NULL, 5);
1225
bool restore_loglevel = true;
1227
restore_loglevel = false;
1230
#endif /* __linux__ */
803
1232
sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
805
1234
perror("socket");
806
returncode = EXIT_FAILURE;
1235
exitcode = EXIT_FAILURE;
1237
if(restore_loglevel){
1238
ret = klogctl(7, NULL, 0);
1243
#endif /* __linux__ */
1244
/* Lower privileges */
809
strcpy(network.ifr_name, interface);
1252
strcpy(network.ifr_name, interface);
810
1253
ret = ioctl(sd, SIOCGIFFLAGS, &network);
813
1255
perror("ioctl SIOCGIFFLAGS");
814
returncode = EXIT_FAILURE;
1257
if(restore_loglevel){
1258
ret = klogctl(7, NULL, 0);
1263
#endif /* __linux__ */
1264
exitcode = EXIT_FAILURE;
1265
/* Lower privileges */
817
1273
if((network.ifr_flags & IFF_UP) == 0){
818
1274
network.ifr_flags |= IFF_UP;
1275
take_down_interface = true;
819
1276
ret = ioctl(sd, SIOCSIFFLAGS, &network);
1278
take_down_interface = false;
821
1279
perror("ioctl SIOCSIFFLAGS");
822
returncode = EXIT_FAILURE;
829
avahi_set_log_function(empty_log);
832
/* Initialize the psuedo-RNG */
833
srand((unsigned int) time(NULL));
835
/* Allocate main loop object */
836
if (!(mc.simple_poll = avahi_simple_poll_new())) {
837
fprintf(stderr, "Failed to create simple poll object.\n");
838
returncode = EXIT_FAILURE;
842
/* Do not publish any local records */
1280
exitcode = EXIT_FAILURE;
1282
if(restore_loglevel){
1283
ret = klogctl(7, NULL, 0);
1288
#endif /* __linux__ */
1289
/* Lower privileges */
1298
/* sleep checking until interface is running */
1299
for(int i=0; i < delay * 4; i++){
1300
ret = ioctl(sd, SIOCGIFFLAGS, &network);
1302
perror("ioctl SIOCGIFFLAGS");
1303
} else if(network.ifr_flags & IFF_RUNNING){
1306
struct timespec sleeptime = { .tv_nsec = 250000000 };
1307
ret = nanosleep(&sleeptime, NULL);
1308
if(ret == -1 and errno != EINTR){
1309
perror("nanosleep");
1312
if(not take_down_interface){
1313
/* We won't need the socket anymore */
1314
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1320
if(restore_loglevel){
1321
/* Restores kernel loglevel to default */
1322
ret = klogctl(7, NULL, 0);
1327
#endif /* __linux__ */
1328
/* Lower privileges */
1330
if(take_down_interface){
1331
/* Lower privileges */
1337
/* Lower privileges permanently */
1349
ret = init_gnutls_global(pubkey, seckey);
1351
fprintf(stderr, "init_gnutls_global failed\n");
1352
exitcode = EXIT_FAILURE;
1355
gnutls_initialized = true;
1362
tempdir_created = true;
1363
if(mkdtemp(tempdir) == NULL){
1364
tempdir_created = false;
1373
if(not init_gpgme(pubkey, seckey, tempdir)){
1374
fprintf(stderr, "init_gpgme failed\n");
1375
exitcode = EXIT_FAILURE;
1378
gpgme_initialized = true;
1385
if(connect_to != NULL){
1386
/* Connect directly, do not use Zeroconf */
1387
/* (Mainly meant for debugging) */
1388
char *address = strrchr(connect_to, ':');
1389
if(address == NULL){
1390
fprintf(stderr, "No colon in address\n");
1391
exitcode = EXIT_FAILURE;
1401
tmpmax = strtoimax(address+1, &tmp, 10);
1402
if(errno != 0 or tmp == address+1 or *tmp != '\0'
1403
or tmpmax != (uint16_t)tmpmax){
1404
fprintf(stderr, "Bad port number\n");
1405
exitcode = EXIT_FAILURE;
1413
port = (uint16_t)tmpmax;
1415
address = connect_to;
1416
/* Colon in address indicates IPv6 */
1418
if(strchr(address, ':') != NULL){
1428
ret = start_mandos_communication(address, port, if_index, af);
1430
exitcode = EXIT_FAILURE;
1432
exitcode = EXIT_SUCCESS;
1442
AvahiServerConfig config;
1443
/* Do not publish any local Zeroconf records */
843
1444
avahi_server_config_init(&config);
844
1445
config.publish_hinfo = 0;
845
1446
config.publish_addresses = 0;
846
1447
config.publish_workstation = 0;
847
1448
config.publish_domain = 0;
849
1450
/* Allocate a new server */
850
mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),
851
&config, NULL, NULL, &error);
853
/* Free the configuration data */
1451
mc.server = avahi_server_new(avahi_simple_poll_get
1452
(mc.simple_poll), &config, NULL,
1455
/* Free the Avahi configuration data */
854
1456
avahi_server_config_free(&config);
856
/* Check if creating the server object succeeded */
858
fprintf(stderr, "Failed to create server: %s\n",
859
avahi_strerror(error));
860
returncode = EXIT_FAILURE;
864
/* Create the service browser */
865
sb = avahi_s_service_browser_new(mc.server, if_index,
867
"_mandos._tcp", NULL, 0,
868
browse_callback, &mc);
870
fprintf(stderr, "Failed to create service browser: %s\n",
871
avahi_strerror(avahi_server_errno(mc.server)));
872
returncode = EXIT_FAILURE;
876
/* Run the main loop */
879
fprintf(stderr, "Starting avahi loop search\n");
882
avahi_simple_poll_loop(simple_poll);
887
fprintf(stderr, "%s exiting\n", argv[0]);
892
avahi_s_service_browser_free(sb);
895
avahi_server_free(mc.server);
898
avahi_simple_poll_free(simple_poll);
1459
/* Check if creating the Avahi server object succeeded */
1460
if(mc.server == NULL){
1461
fprintf(stderr, "Failed to create Avahi server: %s\n",
1462
avahi_strerror(error));
1463
exitcode = EXIT_FAILURE;
1471
/* Create the Avahi service browser */
1472
sb = avahi_s_service_browser_new(mc.server, if_index,
1473
AVAHI_PROTO_UNSPEC, "_mandos._tcp",
1474
NULL, 0, browse_callback, NULL);
1476
fprintf(stderr, "Failed to create service browser: %s\n",
1477
avahi_strerror(avahi_server_errno(mc.server)));
1478
exitcode = EXIT_FAILURE;
1486
/* Run the main loop */
1489
fprintf(stderr, "Starting Avahi loop search\n");
1492
avahi_simple_poll_loop(mc.simple_poll);
1497
fprintf(stderr, "%s exiting\n", argv[0]);
1500
/* Cleanup things */
1502
avahi_s_service_browser_free(sb);
1504
if(mc.server != NULL)
1505
avahi_server_free(mc.server);
1507
if(mc.simple_poll != NULL)
1508
avahi_simple_poll_free(mc.simple_poll);
1510
if(gnutls_initialized){
1511
gnutls_certificate_free_credentials(mc.cred);
1512
gnutls_global_deinit();
1513
gnutls_dh_params_deinit(mc.dh_params);
1516
if(gpgme_initialized){
1517
gpgme_release(mc.ctx);
1520
/* Take down the network interface */
1521
if(take_down_interface){
1522
/* Re-raise priviliges */
1529
ret = ioctl(sd, SIOCGIFFLAGS, &network);
1531
perror("ioctl SIOCGIFFLAGS");
1532
} else if(network.ifr_flags & IFF_UP) {
1533
network.ifr_flags &= ~IFF_UP; /* clear flag */
1534
ret = ioctl(sd, SIOCSIFFLAGS, &network);
1536
perror("ioctl SIOCSIFFLAGS");
1539
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1543
/* Lower privileges permanently */
1552
/* Removes the temp directory used by GPGME */
1553
if(tempdir_created){
1555
struct dirent *direntry;
1556
d = opendir(tempdir);
1558
if(errno != ENOENT){
1563
direntry = readdir(d);
1564
if(direntry == NULL){
1567
/* Skip "." and ".." */
1568
if(direntry->d_name[0] == '.'
1569
and (direntry->d_name[1] == '\0'
1570
or (direntry->d_name[1] == '.'
1571
and direntry->d_name[2] == '\0'))){
1574
char *fullname = NULL;
1575
ret = asprintf(&fullname, "%s/%s", tempdir,
1581
ret = remove(fullname);
1583
fprintf(stderr, "remove(\"%s\"): %s\n", fullname,
1590
ret = rmdir(tempdir);
1591
if(ret == -1 and errno != ENOENT){
1597
sigemptyset(&old_sigterm_action.sa_mask);
1598
old_sigterm_action.sa_handler = SIG_DFL;
1599
ret = (int)TEMP_FAILURE_RETRY(sigaction(signal_received,
1600
&old_sigterm_action,
1603
perror("sigaction");
1606
ret = raise(signal_received);
1607
} while(ret != 0 and errno == EINTR);
1612
TEMP_FAILURE_RETRY(pause());