26
25
* along with this program. If not, see
27
26
* <http://www.gnu.org/licenses/>.
29
* Contact the authors at <mandos@fukt.bsnet.se>.
28
* Contact the authors at <https://www.fukt.bsnet.se/~belorn/> and
29
* <https://www.fukt.bsnet.se/~teddy/>.
32
/* Needed by GPGME, specifically gpgme_data_seek() */
33
#ifndef _LARGEFILE_SOURCE
32
#define _FORTIFY_SOURCE 2
34
34
#define _LARGEFILE_SOURCE
36
#ifndef _FILE_OFFSET_BITS
37
35
#define _FILE_OFFSET_BITS 64
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,
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
41
#include <net/if.h> /* if_nametoindex */
94
43
#include <avahi-core/core.h>
95
44
#include <avahi-core/lookup.h>
96
45
#include <avahi-core/log.h>
98
47
#include <avahi-common/malloc.h>
99
48
#include <avahi-common/error.h>
102
#include <gnutls/gnutls.h> /* All GnuTLS types, constants and
105
init_gnutls_session(),
107
#include <gnutls/openpgp.h>
108
/* gnutls_certificate_set_openpgp_key_file(),
109
GNUTLS_OPENPGP_FMT_BASE64 */
112
#include <gpgme.h> /* All GPGME types, constants and
115
GPGME_PROTOCOL_OpenPGP,
51
#include <sys/types.h> /* socket(), setsockopt(),
53
#include <sys/socket.h> /* socket(), setsockopt(),
55
struct in6_addr, inet_pton() */
56
#include <gnutls/gnutls.h> /* All GnuTLS stuff */
57
#include <gnutls/openpgp.h> /* GnuTLS with openpgp stuff */
59
#include <unistd.h> /* close() */
60
#include <netinet/in.h>
61
#include <stdbool.h> /* true */
62
#include <string.h> /* memset */
63
#include <arpa/inet.h> /* inet_pton() */
64
#include <iso646.h> /* not */
67
#include <errno.h> /* perror() */
74
#define CERT_ROOT "/conf/conf.d/cryptkeyreq/"
76
#define CERTFILE CERT_ROOT "openpgp-client.txt"
77
#define KEYFILE CERT_ROOT "openpgp-client-key.txt"
118
78
#define BUFFER_SIZE 256
120
#define PATHDIR "/conf/conf.d/mandos"
121
#define SECKEY "seckey.txt"
122
#define PUBKEY "pubkey.txt"
124
81
bool debug = false;
125
static const char mandos_protocol_version[] = "1";
126
const char *argp_program_version = "mandos-client " VERSION;
127
const char *argp_program_bug_address = "<mandos@fukt.bsnet.se>";
129
/* Used for passing in values through the Avahi callback functions */
131
AvahiSimplePoll *simple_poll;
84
gnutls_session_t session;
133
85
gnutls_certificate_credentials_t cred;
134
unsigned int dh_bits;
135
86
gnutls_dh_params_t dh_params;
136
const char *priority;
90
ssize_t pgp_packet_decrypt (char *packet, size_t packet_size,
91
char **new_packet, const char *homedir){
92
gpgme_data_t dh_crypto, dh_plain;
140
/* global context so signal handler can reach it*/
141
mandos_context mc = { .simple_poll = NULL, .server = NULL,
142
.dh_bits = 1024, .priority = "SECURE256"
143
":!CTYPE-X.509:+CTYPE-OPENPGP" };
146
* Make additional room in "buffer" for at least BUFFER_SIZE more
147
* bytes. "buffer_capacity" is how much is currently allocated,
148
* "buffer_length" is how much is already used.
150
size_t incbuffer(char **buffer, size_t buffer_length,
151
size_t buffer_capacity){
152
if(buffer_length + BUFFER_SIZE > buffer_capacity){
153
*buffer = realloc(*buffer, buffer_capacity + BUFFER_SIZE);
157
buffer_capacity += BUFFER_SIZE;
159
return buffer_capacity;
165
static bool init_gpgme(const char *seckey,
166
const char *pubkey, const char *tempdir){
96
ssize_t new_packet_capacity = 0;
97
ssize_t new_packet_length = 0;
168
98
gpgme_engine_info_t engine_info;
172
* Helper function to insert pub and seckey to the engine keyring.
174
bool import_key(const char *filename){
177
gpgme_data_t pgp_data;
179
fd = (int)TEMP_FAILURE_RETRY(open(filename, O_RDONLY));
185
rc = gpgme_data_new_from_fd(&pgp_data, fd);
186
if(rc != GPG_ERR_NO_ERROR){
187
fprintf(stderr, "bad gpgme_data_new_from_fd: %s: %s\n",
188
gpgme_strsource(rc), gpgme_strerror(rc));
192
rc = gpgme_op_import(mc.ctx, pgp_data);
193
if(rc != GPG_ERR_NO_ERROR){
194
fprintf(stderr, "bad gpgme_op_import: %s: %s\n",
195
gpgme_strsource(rc), gpgme_strerror(rc));
199
ret = (int)TEMP_FAILURE_RETRY(close(fd));
203
gpgme_data_release(pgp_data);
208
fprintf(stderr, "Initializing GPGME\n");
101
fprintf(stderr, "Trying to decrypt OpenPGP packet\n");
212
105
gpgme_check_version(NULL);
213
rc = gpgme_engine_check_version(GPGME_PROTOCOL_OpenPGP);
214
if(rc != GPG_ERR_NO_ERROR){
215
fprintf(stderr, "bad gpgme_engine_check_version: %s: %s\n",
216
gpgme_strsource(rc), gpgme_strerror(rc));
106
gpgme_engine_check_version(GPGME_PROTOCOL_OpenPGP);
220
/* Set GPGME home directory for the OpenPGP engine only */
221
rc = gpgme_get_engine_info(&engine_info);
222
if(rc != GPG_ERR_NO_ERROR){
108
/* Set GPGME home directory */
109
rc = gpgme_get_engine_info (&engine_info);
110
if (rc != GPG_ERR_NO_ERROR){
223
111
fprintf(stderr, "bad gpgme_get_engine_info: %s: %s\n",
224
112
gpgme_strsource(rc), gpgme_strerror(rc));
227
115
while(engine_info != NULL){
228
116
if(engine_info->protocol == GPGME_PROTOCOL_OpenPGP){
229
117
gpgme_set_engine_info(GPGME_PROTOCOL_OpenPGP,
230
engine_info->file_name, tempdir);
118
engine_info->file_name, homedir);
233
121
engine_info = engine_info->next;
235
123
if(engine_info == NULL){
236
fprintf(stderr, "Could not set GPGME home dir to %s\n", tempdir);
240
/* Create new GPGME "context" */
241
rc = gpgme_new(&(mc.ctx));
242
if(rc != GPG_ERR_NO_ERROR){
243
fprintf(stderr, "bad gpgme_new: %s: %s\n",
244
gpgme_strsource(rc), gpgme_strerror(rc));
248
if(not import_key(pubkey) or not import_key(seckey)){
256
* Decrypt OpenPGP data.
257
* Returns -1 on error
259
static ssize_t pgp_packet_decrypt(const char *cryptotext,
262
gpgme_data_t dh_crypto, dh_plain;
265
size_t plaintext_capacity = 0;
266
ssize_t plaintext_length = 0;
269
fprintf(stderr, "Trying to decrypt OpenPGP data\n");
272
/* Create new GPGME data buffer from memory cryptotext */
273
rc = gpgme_data_new_from_mem(&dh_crypto, cryptotext, crypto_size,
275
if(rc != GPG_ERR_NO_ERROR){
124
fprintf(stderr, "Could not set home dir to %s\n", homedir);
128
/* Create new GPGME data buffer from packet buffer */
129
rc = gpgme_data_new_from_mem(&dh_crypto, packet, packet_size, 0);
130
if (rc != GPG_ERR_NO_ERROR){
276
131
fprintf(stderr, "bad gpgme_data_new_from_mem: %s: %s\n",
277
132
gpgme_strsource(rc), gpgme_strerror(rc));
327
fprintf(stderr, "Decryption of OpenPGP data succeeded\n");
194
/* Delete the GPGME FILE pointer cryptotext data buffer */
195
gpgme_data_release(dh_crypto);
330
197
/* Seek back to the beginning of the GPGME plaintext data buffer */
331
if(gpgme_data_seek(dh_plain, (off_t)0, SEEK_SET) == -1){
332
perror("gpgme_data_seek");
333
plaintext_length = -1;
198
gpgme_data_seek(dh_plain, 0, SEEK_SET);
339
plaintext_capacity = incbuffer(plaintext,
340
(size_t)plaintext_length,
342
if(plaintext_capacity == 0){
344
plaintext_length = -1;
202
if (new_packet_length + BUFFER_SIZE > new_packet_capacity){
203
*new_packet = realloc(*new_packet,
204
(unsigned int)new_packet_capacity
206
if (*new_packet == NULL){
210
new_packet_capacity += BUFFER_SIZE;
348
ret = gpgme_data_read(dh_plain, *plaintext + plaintext_length,
213
ret = gpgme_data_read(dh_plain, *new_packet + new_packet_length,
350
215
/* Print the data, if any */
356
220
perror("gpgme_data_read");
357
plaintext_length = -1;
360
plaintext_length += ret;
364
fprintf(stderr, "Decrypted password is: ");
365
for(ssize_t i = 0; i < plaintext_length; i++){
366
fprintf(stderr, "%02hhX ", (*plaintext)[i]);
368
fprintf(stderr, "\n");
373
/* Delete the GPGME cryptotext data buffer */
374
gpgme_data_release(dh_crypto);
223
new_packet_length += ret;
226
/* FIXME: check characters before printing to screen so to not print
227
terminal control characters */
229
/* fprintf(stderr, "decrypted password is: "); */
230
/* fwrite(*new_packet, 1, new_packet_length, stderr); */
231
/* fprintf(stderr, "\n"); */
376
234
/* Delete the GPGME plaintext data buffer */
377
235
gpgme_data_release(dh_plain);
378
return plaintext_length;
236
return new_packet_length;
381
static const char * safer_gnutls_strerror(int value){
382
const char *ret = gnutls_strerror(value); /* Spurious warning from
383
-Wunreachable-code */
239
static const char * safer_gnutls_strerror (int value) {
240
const char *ret = gnutls_strerror (value);
385
242
ret = "(unknown)";
389
/* GnuTLS log function callback */
390
static void debuggnutls(__attribute__((unused)) int level,
392
fprintf(stderr, "GnuTLS: %s", string);
246
void debuggnutls(__attribute__((unused)) int level,
248
fprintf(stderr, "%s", string);
395
static int init_gnutls_global(const char *pubkeyfilename,
396
const char *seckeyfilename){
251
int initgnutls(encrypted_session *es){
400
256
fprintf(stderr, "Initializing GnuTLS\n");
403
ret = gnutls_global_init();
404
if(ret != GNUTLS_E_SUCCESS){
405
fprintf(stderr, "GnuTLS global_init: %s\n",
406
safer_gnutls_strerror(ret));
259
if ((ret = gnutls_global_init ())
260
!= GNUTLS_E_SUCCESS) {
261
fprintf (stderr, "global_init: %s\n", safer_gnutls_strerror(ret));
411
/* "Use a log level over 10 to enable all debugging options."
414
266
gnutls_global_set_log_level(11);
415
267
gnutls_global_set_log_function(debuggnutls);
418
/* OpenPGP credentials */
419
gnutls_certificate_allocate_credentials(&mc.cred);
420
if(ret != GNUTLS_E_SUCCESS){
421
fprintf(stderr, "GnuTLS memory error: %s\n", /* Spurious warning
425
safer_gnutls_strerror(ret));
426
gnutls_global_deinit();
270
/* openpgp credentials */
271
if ((ret = gnutls_certificate_allocate_credentials (&es->cred))
272
!= GNUTLS_E_SUCCESS) {
273
fprintf (stderr, "memory error: %s\n",
274
safer_gnutls_strerror(ret));
431
fprintf(stderr, "Attempting to use OpenPGP public key %s and"
432
" secret key %s as GnuTLS credentials\n", pubkeyfilename,
279
fprintf(stderr, "Attempting to use OpenPGP certificate %s"
280
" and keyfile %s as GnuTLS credentials\n", CERTFILE,
436
284
ret = gnutls_certificate_set_openpgp_key_file
437
(mc.cred, pubkeyfilename, seckeyfilename,
438
GNUTLS_OPENPGP_FMT_BASE64);
439
if(ret != GNUTLS_E_SUCCESS){
441
"Error[%d] while reading the OpenPGP key pair ('%s',"
442
" '%s')\n", ret, pubkeyfilename, seckeyfilename);
443
fprintf(stderr, "The GnuTLS error is: %s\n",
444
safer_gnutls_strerror(ret));
448
/* GnuTLS server initialization */
449
ret = gnutls_dh_params_init(&mc.dh_params);
450
if(ret != GNUTLS_E_SUCCESS){
451
fprintf(stderr, "Error in GnuTLS DH parameter initialization:"
452
" %s\n", safer_gnutls_strerror(ret));
455
ret = gnutls_dh_params_generate2(mc.dh_params, mc.dh_bits);
456
if(ret != GNUTLS_E_SUCCESS){
457
fprintf(stderr, "Error in GnuTLS prime generation: %s\n",
458
safer_gnutls_strerror(ret));
462
gnutls_certificate_set_dh_params(mc.cred, mc.dh_params);
468
gnutls_certificate_free_credentials(mc.cred);
469
gnutls_global_deinit();
470
gnutls_dh_params_deinit(mc.dh_params);
474
static int init_gnutls_session(gnutls_session_t *session){
476
/* GnuTLS session creation */
477
ret = gnutls_init(session, GNUTLS_SERVER);
478
if(ret != GNUTLS_E_SUCCESS){
285
(es->cred, CERTFILE, KEYFILE, GNUTLS_OPENPGP_FMT_BASE64);
286
if (ret != GNUTLS_E_SUCCESS) {
288
(stderr, "Error[%d] while reading the OpenPGP key pair ('%s',"
290
ret, CERTFILE, KEYFILE);
291
fprintf(stdout, "The Error is: %s\n",
292
safer_gnutls_strerror(ret));
296
//GnuTLS server initialization
297
if ((ret = gnutls_dh_params_init (&es->dh_params))
298
!= GNUTLS_E_SUCCESS) {
299
fprintf (stderr, "Error in dh parameter initialization: %s\n",
300
safer_gnutls_strerror(ret));
304
if ((ret = gnutls_dh_params_generate2 (es->dh_params, DH_BITS))
305
!= GNUTLS_E_SUCCESS) {
306
fprintf (stderr, "Error in prime generation: %s\n",
307
safer_gnutls_strerror(ret));
311
gnutls_certificate_set_dh_params (es->cred, es->dh_params);
313
// GnuTLS session creation
314
if ((ret = gnutls_init (&es->session, GNUTLS_SERVER))
315
!= GNUTLS_E_SUCCESS){
479
316
fprintf(stderr, "Error in GnuTLS session initialization: %s\n",
480
317
safer_gnutls_strerror(ret));
485
ret = gnutls_priority_set_direct(*session, mc.priority, &err);
486
if(ret != GNUTLS_E_SUCCESS){
487
fprintf(stderr, "Syntax error at: %s\n", err);
488
fprintf(stderr, "GnuTLS error: %s\n",
489
safer_gnutls_strerror(ret));
490
gnutls_deinit(*session);
320
if ((ret = gnutls_priority_set_direct (es->session, "NORMAL", &err))
321
!= GNUTLS_E_SUCCESS) {
322
fprintf(stderr, "Syntax error at: %s\n", err);
323
fprintf(stderr, "GnuTLS error: %s\n",
324
safer_gnutls_strerror(ret));
495
ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,
497
if(ret != GNUTLS_E_SUCCESS){
498
fprintf(stderr, "Error setting GnuTLS credentials: %s\n",
328
if ((ret = gnutls_credentials_set
329
(es->session, GNUTLS_CRD_CERTIFICATE, es->cred))
330
!= GNUTLS_E_SUCCESS) {
331
fprintf(stderr, "Error setting a credentials set: %s\n",
499
332
safer_gnutls_strerror(ret));
500
gnutls_deinit(*session);
504
336
/* ignore client certificate if any. */
505
gnutls_certificate_server_set_request(*session,
337
gnutls_certificate_server_set_request (es->session,
508
gnutls_dh_set_prime_bits(*session, mc.dh_bits);
340
gnutls_dh_set_prime_bits (es->session, DH_BITS);
513
/* Avahi log function callback */
514
static void empty_log(__attribute__((unused)) AvahiLogLevel level,
515
__attribute__((unused)) const char *txt){}
517
sig_atomic_t quit_now = 0;
518
int signal_received = 0;
520
/* Called when a Mandos server is found */
521
static int start_mandos_communication(const char *ip, uint16_t port,
522
AvahiIfIndex if_index,
524
int ret, tcp_sd = -1;
527
struct sockaddr_in in;
528
struct sockaddr_in6 in6;
345
void empty_log(__attribute__((unused)) AvahiLogLevel level,
346
__attribute__((unused)) const char *txt){}
348
int start_mandos_communication(char *ip, uint16_t port,
349
unsigned int if_index){
351
struct sockaddr_in6 to;
352
encrypted_session es;
530
353
char *buffer = NULL;
531
354
char *decrypted_buffer;
532
355
size_t buffer_length = 0;
533
356
size_t buffer_capacity = 0;
357
ssize_t decrypted_buffer_size;
536
gnutls_session_t session;
537
int pf; /* Protocol family */
551
fprintf(stderr, "Bad address family: %d\n", af);
555
ret = init_gnutls_session(&session);
359
char interface[IF_NAMESIZE];
561
fprintf(stderr, "Setting up a TCP connection to %s, port %" PRIu16
362
fprintf(stderr, "Setting up a tcp connection to %s\n", ip);
565
tcp_sd = socket(pf, SOCK_STREAM, 0);
365
tcp_sd = socket(PF_INET6, SOCK_STREAM, 0);
567
367
perror("socket");
576
memset(&to, 0, sizeof(to));
578
to.in6.sin6_family = (sa_family_t)af;
579
ret = inet_pton(af, ip, &to.in6.sin6_addr);
581
to.in.sin_family = (sa_family_t)af;
582
ret = inet_pton(af, ip, &to.in.sin_addr);
371
if(if_indextoname(if_index, interface) == NULL){
373
perror("if_indextoname");
379
fprintf(stderr, "Binding to interface %s\n", interface);
382
ret = setsockopt(tcp_sd, SOL_SOCKET, SO_BINDTODEVICE, interface, 5);
384
perror("setsockopt bindtodevice");
388
memset(&to,0,sizeof(to));
389
to.sin6_family = AF_INET6;
390
ret = inet_pton(AF_INET6, ip, &to.sin6_addr);
585
392
perror("inet_pton");
590
396
fprintf(stderr, "Bad address: %s\n", ip);
595
to.in6.sin6_port = htons(port); /* Spurious warnings from
597
-Wunreachable-code */
599
if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */
600
(&to.in6.sin6_addr)){ /* -Wstrict-aliasing=2 or lower and
602
if(if_index == AVAHI_IF_UNSPEC){
603
fprintf(stderr, "An IPv6 link-local address is incomplete"
604
" without a network interface\n");
608
/* Set the network interface number as scope */
609
to.in6.sin6_scope_id = (uint32_t)if_index;
612
to.in.sin_port = htons(port); /* Spurious warnings from
614
-Wunreachable-code */
399
/* Spurious warnings for the next line, see for instance
400
<http://bugs.debian.org/488884> */
401
to.sin6_port = htons(port);
403
to.sin6_scope_id = (uint32_t)if_index;
622
if(af == AF_INET6 and if_index != AVAHI_IF_UNSPEC){
623
char interface[IF_NAMESIZE];
624
if(if_indextoname((unsigned int)if_index, interface) == NULL){
625
perror("if_indextoname");
627
fprintf(stderr, "Connection to: %s%%%s, port %" PRIu16 "\n",
628
ip, interface, port);
631
fprintf(stderr, "Connection to: %s, port %" PRIu16 "\n", ip,
634
char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?
635
INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";
638
pcret = inet_ntop(af, &(to.in6.sin6_addr), addrstr,
641
pcret = inet_ntop(af, &(to.in.sin_addr), addrstr,
647
if(strcmp(addrstr, ip) != 0){
648
fprintf(stderr, "Canonical address form: %s\n", addrstr);
658
ret = connect(tcp_sd, &to.in6, sizeof(to));
660
ret = connect(tcp_sd, &to.in, sizeof(to)); /* IPv4 */
406
fprintf(stderr, "Connection to: %s\n", ip);
409
ret = connect(tcp_sd, (struct sockaddr *) &to, sizeof(to));
663
411
perror("connect");
415
ret = initgnutls (&es);
672
const char *out = mandos_protocol_version;
675
size_t out_size = strlen(out);
676
ret = (int)TEMP_FAILURE_RETRY(write(tcp_sd, out + written,
677
out_size - written));
683
written += (size_t)ret;
684
if(written < out_size){
687
if(out == mandos_protocol_version){
421
gnutls_transport_set_ptr (es.session,
422
(gnutls_transport_ptr_t) tcp_sd);
701
425
fprintf(stderr, "Establishing TLS session with %s\n", ip);
708
gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);
715
ret = gnutls_handshake(session);
719
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
721
if(ret != GNUTLS_E_SUCCESS){
723
fprintf(stderr, "*** GnuTLS Handshake failed ***\n");
428
ret = gnutls_handshake (es.session);
430
if (ret != GNUTLS_E_SUCCESS){
431
fprintf(stderr, "\n*** Handshake failed ***\n");
730
/* Read OpenPGP packet that contains the wanted password */
437
//Retrieve OpenPGP packet that contains the wanted password
733
fprintf(stderr, "Retrieving OpenPGP encrypted password from %s\n",
440
fprintf(stderr, "Retrieving pgp encrypted password from %s\n",
743
buffer_capacity = incbuffer(&buffer, buffer_length,
745
if(buffer_capacity == 0){
755
sret = gnutls_record_recv(session, buffer+buffer_length,
445
if (buffer_length + BUFFER_SIZE > buffer_capacity){
446
buffer = realloc(buffer, buffer_capacity + BUFFER_SIZE);
451
buffer_capacity += BUFFER_SIZE;
454
ret = gnutls_record_recv
455
(es.session, buffer+buffer_length, BUFFER_SIZE);
762
461
case GNUTLS_E_INTERRUPTED:
763
462
case GNUTLS_E_AGAIN:
765
464
case GNUTLS_E_REHANDSHAKE:
767
ret = gnutls_handshake(session);
772
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
774
fprintf(stderr, "*** GnuTLS Re-handshake failed ***\n");
465
ret = gnutls_handshake (es.session);
467
fprintf(stderr, "\n*** Handshake failed ***\n");
781
474
fprintf(stderr, "Unknown error while reading data from"
782
" encrypted session with Mandos server\n");
475
" encrypted session with mandos server\n");
784
gnutls_bye(session, GNUTLS_SHUT_RDWR);
477
gnutls_bye (es.session, GNUTLS_SHUT_RDWR);
788
buffer_length += (size_t) sret;
481
buffer_length += (size_t) ret;
793
fprintf(stderr, "Closing TLS session\n");
800
gnutls_bye(session, GNUTLS_SHUT_RDWR);
806
if(buffer_length > 0){
807
ssize_t decrypted_buffer_size;
485
if (buffer_length > 0){
808
486
decrypted_buffer_size = pgp_packet_decrypt(buffer,
811
if(decrypted_buffer_size >= 0){
814
while(written < (size_t) decrypted_buffer_size){
819
ret = (int)fwrite(decrypted_buffer + written, 1,
820
(size_t)decrypted_buffer_size - written,
490
if (decrypted_buffer_size >= 0){
491
while(decrypted_buffer_size > 0){
492
ret = fwrite (decrypted_buffer, 1, (size_t)decrypted_buffer_size,
822
494
if(ret == 0 and ferror(stdout)){
824
496
fprintf(stderr, "Error writing encrypted data: %s\n",
830
written += (size_t)ret;
502
decrypted_buffer += ret;
503
decrypted_buffer_size -= ret;
832
505
free(decrypted_buffer);
840
/* Shutdown procedure */
514
fprintf(stderr, "Closing TLS session\n");
845
ret = (int)TEMP_FAILURE_RETRY(close(tcp_sd));
850
gnutls_deinit(session);
518
gnutls_bye (es.session, GNUTLS_SHUT_RDWR);
521
gnutls_deinit (es.session);
522
gnutls_certificate_free_credentials (es.cred);
523
gnutls_global_deinit ();
857
static void resolve_callback(AvahiSServiceResolver *r,
858
AvahiIfIndex interface,
860
AvahiResolverEvent event,
864
const char *host_name,
865
const AvahiAddress *address,
867
AVAHI_GCC_UNUSED AvahiStringList *txt,
868
AVAHI_GCC_UNUSED AvahiLookupResultFlags
870
AVAHI_GCC_UNUSED void* userdata){
527
static AvahiSimplePoll *simple_poll = NULL;
528
static AvahiServer *server = NULL;
530
static void resolve_callback(
531
AvahiSServiceResolver *r,
532
AVAHI_GCC_UNUSED AvahiIfIndex interface,
533
AVAHI_GCC_UNUSED AvahiProtocol protocol,
534
AvahiResolverEvent event,
538
const char *host_name,
539
const AvahiAddress *address,
541
AVAHI_GCC_UNUSED AvahiStringList *txt,
542
AVAHI_GCC_UNUSED AvahiLookupResultFlags flags,
543
AVAHI_GCC_UNUSED void* userdata) {
873
547
/* Called whenever a service has been resolved successfully or
882
552
case AVAHI_RESOLVER_FAILURE:
883
fprintf(stderr, "(Avahi Resolver) Failed to resolve service '%s'"
884
" of type '%s' in domain '%s': %s\n", name, type, domain,
885
avahi_strerror(avahi_server_errno(mc.server)));
553
fprintf(stderr, "(Resolver) Failed to resolve service '%s' of"
554
" type '%s' in domain '%s': %s\n", name, type, domain,
555
avahi_strerror(avahi_server_errno(server)));
888
558
case AVAHI_RESOLVER_FOUND:
890
560
char ip[AVAHI_ADDRESS_STR_MAX];
891
561
avahi_address_snprint(ip, sizeof(ip), address);
893
fprintf(stderr, "Mandos server \"%s\" found on %s (%s, %"
894
PRIdMAX ") on port %" PRIu16 "\n", name, host_name,
895
ip, (intmax_t)interface, port);
563
fprintf(stderr, "Mandos server found on %s (%s) on port %d\n",
564
host_name, ip, port);
897
int ret = start_mandos_communication(ip, port, interface,
898
avahi_proto_to_af(proto));
900
avahi_simple_poll_quit(mc.simple_poll);
566
int ret = start_mandos_communication(ip, port,
904
576
avahi_s_service_resolver_free(r);
907
static void browse_callback(AvahiSServiceBrowser *b,
908
AvahiIfIndex interface,
909
AvahiProtocol protocol,
910
AvahiBrowserEvent event,
914
AVAHI_GCC_UNUSED AvahiLookupResultFlags
916
AVAHI_GCC_UNUSED void* userdata){
919
/* Called whenever a new services becomes available on the LAN or
920
is removed from the LAN */
928
case AVAHI_BROWSER_FAILURE:
930
fprintf(stderr, "(Avahi browser) %s\n",
931
avahi_strerror(avahi_server_errno(mc.server)));
932
avahi_simple_poll_quit(mc.simple_poll);
935
case AVAHI_BROWSER_NEW:
936
/* We ignore the returned Avahi resolver object. In the callback
937
function we free it. If the Avahi server is terminated before
938
the callback function is called the Avahi server will free the
941
if(avahi_s_service_resolver_new(mc.server, interface, protocol,
942
name, type, domain, protocol, 0,
943
resolve_callback, NULL) == NULL)
944
fprintf(stderr, "Avahi: Failed to resolve service '%s': %s\n",
945
name, avahi_strerror(avahi_server_errno(mc.server)));
948
case AVAHI_BROWSER_REMOVE:
951
case AVAHI_BROWSER_ALL_FOR_NOW:
952
case AVAHI_BROWSER_CACHE_EXHAUSTED:
954
fprintf(stderr, "No Mandos server found, still searching...\n");
960
/* stop main loop after sigterm has been called */
961
static void handle_sigterm(int sig){
966
signal_received = sig;
967
int old_errno = errno;
968
if(mc.simple_poll != NULL){
969
avahi_simple_poll_quit(mc.simple_poll);
974
int main(int argc, char *argv[]){
975
AvahiSServiceBrowser *sb = NULL;
980
int exitcode = EXIT_SUCCESS;
981
const char *interface = "eth0";
982
struct ifreq network;
984
bool take_down_interface = false;
987
char *connect_to = NULL;
988
char tempdir[] = "/tmp/mandosXXXXXX";
989
bool tempdir_created = false;
990
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
991
const char *seckey = PATHDIR "/" SECKEY;
992
const char *pubkey = PATHDIR "/" PUBKEY;
994
bool gnutls_initialized = false;
995
bool gpgme_initialized = false;
998
struct sigaction old_sigterm_action;
999
struct sigaction sigterm_action = { .sa_handler = handle_sigterm };
1002
struct argp_option options[] = {
1003
{ .name = "debug", .key = 128,
1004
.doc = "Debug mode", .group = 3 },
1005
{ .name = "connect", .key = 'c',
1006
.arg = "ADDRESS:PORT",
1007
.doc = "Connect directly to a specific Mandos server",
1009
{ .name = "interface", .key = 'i',
1011
.doc = "Network interface that will be used to search for"
1014
{ .name = "seckey", .key = 's',
1016
.doc = "OpenPGP secret key file base name",
1018
{ .name = "pubkey", .key = 'p',
1020
.doc = "OpenPGP public key file base name",
1022
{ .name = "dh-bits", .key = 129,
1024
.doc = "Bit length of the prime number used in the"
1025
" Diffie-Hellman key exchange",
1027
{ .name = "priority", .key = 130,
1029
.doc = "GnuTLS priority string for the TLS handshake",
1031
{ .name = "delay", .key = 131,
1033
.doc = "Maximum delay to wait for interface startup",
1038
error_t parse_opt(int key, char *arg,
1039
struct argp_state *state){
1041
case 128: /* --debug */
1044
case 'c': /* --connect */
1047
case 'i': /* --interface */
1050
case 's': /* --seckey */
1053
case 'p': /* --pubkey */
1056
case 129: /* --dh-bits */
1058
tmpmax = strtoimax(arg, &tmp, 10);
1059
if(errno != 0 or tmp == arg or *tmp != '\0'
1060
or tmpmax != (typeof(mc.dh_bits))tmpmax){
1061
fprintf(stderr, "Bad number of DH bits\n");
1064
mc.dh_bits = (typeof(mc.dh_bits))tmpmax;
1066
case 130: /* --priority */
1069
case 131: /* --delay */
1071
delay = strtof(arg, &tmp);
1072
if(errno != 0 or tmp == arg or *tmp != '\0'){
1073
fprintf(stderr, "Bad delay\n");
1082
return ARGP_ERR_UNKNOWN;
1087
struct argp argp = { .options = options, .parser = parse_opt,
1089
.doc = "Mandos client -- Get and decrypt"
1090
" passwords from a Mandos server" };
1091
ret = argp_parse(&argp, argc, argv, 0, 0, NULL);
1092
if(ret == ARGP_ERR_UNKNOWN){
1093
fprintf(stderr, "Unknown error while parsing arguments\n");
1094
exitcode = EXIT_FAILURE;
1100
avahi_set_log_function(empty_log);
1103
/* Initialize Avahi early so avahi_simple_poll_quit() can be called
1104
from the signal handler */
1105
/* Initialize the pseudo-RNG for Avahi */
1106
srand((unsigned int) time(NULL));
1107
mc.simple_poll = avahi_simple_poll_new();
1108
if(mc.simple_poll == NULL){
1109
fprintf(stderr, "Avahi: Failed to create simple poll object.\n");
1110
exitcode = EXIT_FAILURE;
1114
sigemptyset(&sigterm_action.sa_mask);
1115
ret = sigaddset(&sigterm_action.sa_mask, SIGINT);
1117
perror("sigaddset");
1118
exitcode = EXIT_FAILURE;
1121
ret = sigaddset(&sigterm_action.sa_mask, SIGHUP);
1123
perror("sigaddset");
1124
exitcode = EXIT_FAILURE;
1127
ret = sigaddset(&sigterm_action.sa_mask, SIGTERM);
1129
perror("sigaddset");
1130
exitcode = EXIT_FAILURE;
1133
/* Need to check if the handler is SIG_IGN before handling:
1134
| [[info:libc:Initial Signal Actions]] |
1135
| [[info:libc:Basic Signal Handling]] |
1137
ret = sigaction(SIGINT, NULL, &old_sigterm_action);
1139
perror("sigaction");
1140
return EXIT_FAILURE;
1142
if(old_sigterm_action.sa_handler != SIG_IGN){
1143
ret = sigaction(SIGINT, &sigterm_action, NULL);
1145
perror("sigaction");
1146
exitcode = EXIT_FAILURE;
1150
ret = sigaction(SIGHUP, NULL, &old_sigterm_action);
1152
perror("sigaction");
1153
return EXIT_FAILURE;
1155
if(old_sigterm_action.sa_handler != SIG_IGN){
1156
ret = sigaction(SIGHUP, &sigterm_action, NULL);
1158
perror("sigaction");
1159
exitcode = EXIT_FAILURE;
1163
ret = sigaction(SIGTERM, NULL, &old_sigterm_action);
1165
perror("sigaction");
1166
return EXIT_FAILURE;
1168
if(old_sigterm_action.sa_handler != SIG_IGN){
1169
ret = sigaction(SIGTERM, &sigterm_action, NULL);
1171
perror("sigaction");
1172
exitcode = EXIT_FAILURE;
1177
/* If the interface is down, bring it up */
1178
if(interface[0] != '\0'){
1179
if_index = (AvahiIfIndex) if_nametoindex(interface);
1181
fprintf(stderr, "No such interface: \"%s\"\n", interface);
1182
exitcode = EXIT_FAILURE;
1191
/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO
1192
messages to mess up the prompt */
1193
ret = klogctl(8, NULL, 5);
1194
bool restore_loglevel = true;
1196
restore_loglevel = false;
1199
#endif /* __linux__ */
1201
sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1204
exitcode = EXIT_FAILURE;
1206
if(restore_loglevel){
1207
ret = klogctl(7, NULL, 0);
1212
#endif /* __linux__ */
1215
strcpy(network.ifr_name, interface);
1216
ret = ioctl(sd, SIOCGIFFLAGS, &network);
1218
perror("ioctl SIOCGIFFLAGS");
1220
if(restore_loglevel){
1221
ret = klogctl(7, NULL, 0);
1226
#endif /* __linux__ */
1227
exitcode = EXIT_FAILURE;
1230
if((network.ifr_flags & IFF_UP) == 0){
1231
network.ifr_flags |= IFF_UP;
1232
take_down_interface = true;
1233
ret = ioctl(sd, SIOCSIFFLAGS, &network);
1235
take_down_interface = false;
1236
perror("ioctl SIOCSIFFLAGS");
1237
exitcode = EXIT_FAILURE;
1239
if(restore_loglevel){
1240
ret = klogctl(7, NULL, 0);
1245
#endif /* __linux__ */
1249
/* sleep checking until interface is running */
1250
for(int i=0; i < delay * 4; i++){
1251
ret = ioctl(sd, SIOCGIFFLAGS, &network);
1253
perror("ioctl SIOCGIFFLAGS");
1254
} else if(network.ifr_flags & IFF_RUNNING){
1257
struct timespec sleeptime = { .tv_nsec = 250000000 };
1258
ret = nanosleep(&sleeptime, NULL);
1259
if(ret == -1 and errno != EINTR){
1260
perror("nanosleep");
1263
if(not take_down_interface){
1264
/* We won't need the socket anymore */
1265
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1271
if(restore_loglevel){
1272
/* Restores kernel loglevel to default */
1273
ret = klogctl(7, NULL, 0);
1278
#endif /* __linux__ */
1288
/* Drop any group privileges we might have, just to be safe */
1295
/* Drop user privileges */
1297
/* Will we need privileges later? */
1298
if(take_down_interface){
1299
/* Drop user privileges temporarily */
1305
/* Drop user privileges permanently */
1316
ret = init_gnutls_global(pubkey, seckey);
1318
fprintf(stderr, "init_gnutls_global failed\n");
1319
exitcode = EXIT_FAILURE;
1322
gnutls_initialized = true;
1329
tempdir_created = true;
1330
if(mkdtemp(tempdir) == NULL){
1331
tempdir_created = false;
1340
if(not init_gpgme(pubkey, seckey, tempdir)){
1341
fprintf(stderr, "init_gpgme failed\n");
1342
exitcode = EXIT_FAILURE;
1345
gpgme_initialized = true;
1352
if(connect_to != NULL){
1353
/* Connect directly, do not use Zeroconf */
1354
/* (Mainly meant for debugging) */
1355
char *address = strrchr(connect_to, ':');
1356
if(address == NULL){
1357
fprintf(stderr, "No colon in address\n");
1358
exitcode = EXIT_FAILURE;
1368
tmpmax = strtoimax(address+1, &tmp, 10);
1369
if(errno != 0 or tmp == address+1 or *tmp != '\0'
1370
or tmpmax != (uint16_t)tmpmax){
1371
fprintf(stderr, "Bad port number\n");
1372
exitcode = EXIT_FAILURE;
1380
port = (uint16_t)tmpmax;
1382
address = connect_to;
1383
/* Colon in address indicates IPv6 */
1385
if(strchr(address, ':') != NULL){
1395
ret = start_mandos_communication(address, port, if_index, af);
1397
exitcode = EXIT_FAILURE;
1399
exitcode = EXIT_SUCCESS;
579
static void browse_callback(
580
AvahiSServiceBrowser *b,
581
AvahiIfIndex interface,
582
AvahiProtocol protocol,
583
AvahiBrowserEvent event,
587
AVAHI_GCC_UNUSED AvahiLookupResultFlags flags,
590
AvahiServer *s = userdata;
593
/* Called whenever a new services becomes available on the LAN or
594
is removed from the LAN */
598
case AVAHI_BROWSER_FAILURE:
600
fprintf(stderr, "(Browser) %s\n",
601
avahi_strerror(avahi_server_errno(server)));
602
avahi_simple_poll_quit(simple_poll);
605
case AVAHI_BROWSER_NEW:
606
/* We ignore the returned resolver object. In the callback
607
function we free it. If the server is terminated before
608
the callback function is called the server will free
609
the resolver for us. */
611
if (!(avahi_s_service_resolver_new(s, interface, protocol, name,
613
AVAHI_PROTO_INET6, 0,
614
resolve_callback, s)))
615
fprintf(stderr, "Failed to resolve service '%s': %s\n", name,
616
avahi_strerror(avahi_server_errno(s)));
619
case AVAHI_BROWSER_REMOVE:
622
case AVAHI_BROWSER_ALL_FOR_NOW:
623
case AVAHI_BROWSER_CACHE_EXHAUSTED:
628
int main(AVAHI_GCC_UNUSED int argc, AVAHI_GCC_UNUSED char*argv[]) {
1409
629
AvahiServerConfig config;
1410
/* Do not publish any local Zeroconf records */
630
AvahiSServiceBrowser *sb = NULL;
633
int returncode = EXIT_SUCCESS;
634
const char *interface = "eth0";
637
static struct option long_options[] = {
638
{"debug", no_argument, (int *)&debug, 1},
639
{"interface", required_argument, 0, 'i'},
642
int option_index = 0;
643
ret = getopt_long (argc, argv, "i:", long_options,
662
avahi_set_log_function(empty_log);
665
/* Initialize the psuedo-RNG */
666
srand((unsigned int) time(NULL));
668
/* Allocate main loop object */
669
if (!(simple_poll = avahi_simple_poll_new())) {
670
fprintf(stderr, "Failed to create simple poll object.\n");
675
/* Do not publish any local records */
1411
676
avahi_server_config_init(&config);
1412
677
config.publish_hinfo = 0;
1413
678
config.publish_addresses = 0;
1414
679
config.publish_workstation = 0;
1415
680
config.publish_domain = 0;
1417
682
/* Allocate a new server */
1418
mc.server = avahi_server_new(avahi_simple_poll_get
1419
(mc.simple_poll), &config, NULL,
1422
/* Free the Avahi configuration data */
683
server = avahi_server_new(avahi_simple_poll_get(simple_poll),
684
&config, NULL, NULL, &error);
686
/* Free the configuration data */
1423
687
avahi_server_config_free(&config);
1426
/* Check if creating the Avahi server object succeeded */
1427
if(mc.server == NULL){
1428
fprintf(stderr, "Failed to create Avahi server: %s\n",
1429
avahi_strerror(error));
1430
exitcode = EXIT_FAILURE;
1438
/* Create the Avahi service browser */
1439
sb = avahi_s_service_browser_new(mc.server, if_index,
1440
AVAHI_PROTO_UNSPEC, "_mandos._tcp",
1441
NULL, 0, browse_callback, NULL);
1443
fprintf(stderr, "Failed to create service browser: %s\n",
1444
avahi_strerror(avahi_server_errno(mc.server)));
1445
exitcode = EXIT_FAILURE;
1453
/* Run the main loop */
1456
fprintf(stderr, "Starting Avahi loop search\n");
1459
avahi_simple_poll_loop(mc.simple_poll);
1464
fprintf(stderr, "%s exiting\n", argv[0]);
1467
/* Cleanup things */
1469
avahi_s_service_browser_free(sb);
1471
if(mc.server != NULL)
1472
avahi_server_free(mc.server);
1474
if(mc.simple_poll != NULL)
1475
avahi_simple_poll_free(mc.simple_poll);
1477
if(gnutls_initialized){
1478
gnutls_certificate_free_credentials(mc.cred);
1479
gnutls_global_deinit();
1480
gnutls_dh_params_deinit(mc.dh_params);
1483
if(gpgme_initialized){
1484
gpgme_release(mc.ctx);
1487
/* Take down the network interface */
1488
if(take_down_interface){
1489
/* Re-raise priviliges */
1496
ret = ioctl(sd, SIOCGIFFLAGS, &network);
1498
perror("ioctl SIOCGIFFLAGS");
1499
} else if(network.ifr_flags & IFF_UP) {
1500
network.ifr_flags &= ~IFF_UP; /* clear flag */
1501
ret = ioctl(sd, SIOCSIFFLAGS, &network);
1503
perror("ioctl SIOCSIFFLAGS");
1506
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1510
/* Lower privileges, permanently this time */
1519
/* Removes the temp directory used by GPGME */
1520
if(tempdir_created){
1522
struct dirent *direntry;
1523
d = opendir(tempdir);
1525
if(errno != ENOENT){
1530
direntry = readdir(d);
1531
if(direntry == NULL){
1534
/* Skip "." and ".." */
1535
if(direntry->d_name[0] == '.'
1536
and (direntry->d_name[1] == '\0'
1537
or (direntry->d_name[1] == '.'
1538
and direntry->d_name[2] == '\0'))){
1541
char *fullname = NULL;
1542
ret = asprintf(&fullname, "%s/%s", tempdir,
1548
ret = remove(fullname);
1550
fprintf(stderr, "remove(\"%s\"): %s\n", fullname,
1557
ret = rmdir(tempdir);
1558
if(ret == -1 and errno != ENOENT){
1564
sigemptyset(&old_sigterm_action.sa_mask);
1565
old_sigterm_action.sa_handler = SIG_DFL;
1566
ret = sigaction(signal_received, &old_sigterm_action, NULL);
1568
perror("sigaction");
1570
raise(signal_received);
689
/* Check if creating the server object succeeded */
691
fprintf(stderr, "Failed to create server: %s\n",
692
avahi_strerror(error));
693
returncode = EXIT_FAILURE;
697
/* Create the service browser */
698
sb = avahi_s_service_browser_new(server,
700
if_nametoindex(interface),
702
"_mandos._tcp", NULL, 0,
703
browse_callback, server);
705
fprintf(stderr, "Failed to create service browser: %s\n",
706
avahi_strerror(avahi_server_errno(server)));
707
returncode = EXIT_FAILURE;
711
/* Run the main loop */
714
fprintf(stderr, "Starting avahi loop search\n");
717
avahi_simple_poll_loop(simple_poll);
722
fprintf(stderr, "%s exiting\n", argv[0]);
727
avahi_s_service_browser_free(sb);
730
avahi_server_free(server);
733
avahi_simple_poll_free(simple_poll);