32
31
/* Needed by GPGME, specifically gpgme_data_seek() */
33
#ifndef _LARGEFILE_SOURCE
34
32
#define _LARGEFILE_SOURCE
36
#ifndef _FILE_OFFSET_BITS
37
33
#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, srand(),
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(), sleep() */
39
#include <net/if.h> /* if_nametoindex */
40
#include <sys/ioctl.h> /* ioctl, ifreq, SIOCGIFFLAGS, IFF_UP,
67
42
#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, inet_ntop() */
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,
85
#include <sysexits.h> /* EX_OSERR, EX_USAGE, EX_UNAVAILABLE,
86
EX_NOHOST, EX_IOERR, EX_PROTOCOL */
89
#include <sys/klog.h> /* klogctl() */
90
#endif /* __linux__ */
93
/* All Avahi types, constants and functions
96
45
#include <avahi-core/core.h>
97
46
#include <avahi-core/lookup.h>
98
47
#include <avahi-core/log.h>
100
49
#include <avahi-common/malloc.h>
101
50
#include <avahi-common/error.h>
104
#include <gnutls/gnutls.h> /* All GnuTLS types, constants and
107
init_gnutls_session(),
109
#include <gnutls/openpgp.h>
110
/* gnutls_certificate_set_openpgp_key_file(),
111
GNUTLS_OPENPGP_FMT_BASE64 */
114
#include <gpgme.h> /* All GPGME types, constants and
117
GPGME_PROTOCOL_OpenPGP,
53
#include <sys/types.h> /* socket(), inet_pton() */
54
#include <sys/socket.h> /* socket(), struct sockaddr_in6,
55
struct in6_addr, inet_pton() */
56
#include <gnutls/gnutls.h> /* All GnuTLS stuff */
57
#include <gnutls/openpgp.h> /* GnuTLS with openpgp stuff */
59
#include <unistd.h> /* close() */
60
#include <netinet/in.h>
61
#include <stdbool.h> /* true */
62
#include <string.h> /* memset */
63
#include <arpa/inet.h> /* inet_pton() */
64
#include <iso646.h> /* not */
67
#include <errno.h> /* perror() */
120
73
#define BUFFER_SIZE 256
122
#define PATHDIR "/conf/conf.d/mandos"
123
#define SECKEY "seckey.txt"
124
#define PUBKEY "pubkey.txt"
75
static const char *keydir = "/conf/conf.d/mandos";
76
static const char *pubkeyfile = "pubkey.txt";
77
static const char *seckeyfile = "seckey.txt";
126
79
bool debug = false;
127
static const char mandos_protocol_version[] = "1";
128
const char *argp_program_version = "mandos-client " VERSION;
129
const char *argp_program_bug_address = "<mandos@fukt.bsnet.se>";
130
static const char sys_class_net[] = "/sys/class/net";
131
char *connect_to = NULL;
133
/* Used for passing in values through the Avahi callback functions */
81
/* Used for passing in values through all the callback functions */
135
83
AvahiSimplePoll *simple_poll;
136
84
AvahiServer *server;
137
85
gnutls_certificate_credentials_t cred;
138
86
unsigned int dh_bits;
139
gnutls_dh_params_t dh_params;
140
87
const char *priority;
91
* Decrypt OpenPGP data using keyrings in HOMEDIR.
94
static ssize_t pgp_packet_decrypt (const char *cryptotext,
98
gpgme_data_t dh_crypto, dh_plain;
144
/* global context so signal handler can reach it*/
145
mandos_context mc = { .simple_poll = NULL, .server = NULL,
146
.dh_bits = 1024, .priority = "SECURE256"
147
":!CTYPE-X.509:+CTYPE-OPENPGP" };
149
sig_atomic_t quit_now = 0;
150
int signal_received = 0;
153
* Make additional room in "buffer" for at least BUFFER_SIZE more
154
* bytes. "buffer_capacity" is how much is currently allocated,
155
* "buffer_length" is how much is already used.
157
size_t incbuffer(char **buffer, size_t buffer_length,
158
size_t buffer_capacity){
159
if(buffer_length + BUFFER_SIZE > buffer_capacity){
160
*buffer = realloc(*buffer, buffer_capacity + BUFFER_SIZE);
164
buffer_capacity += BUFFER_SIZE;
166
return buffer_capacity;
172
static bool init_gpgme(const char *seckey,
173
const char *pubkey, const char *tempdir){
174
100
gpgme_error_t rc;
102
ssize_t plaintext_capacity = 0;
103
ssize_t plaintext_length = 0;
175
104
gpgme_engine_info_t engine_info;
179
* Helper function to insert pub and seckey to the engine keyring.
181
bool import_key(const char *filename){
184
gpgme_data_t pgp_data;
186
fd = (int)TEMP_FAILURE_RETRY(open(filename, O_RDONLY));
192
rc = gpgme_data_new_from_fd(&pgp_data, fd);
193
if(rc != GPG_ERR_NO_ERROR){
194
fprintf(stderr, "bad gpgme_data_new_from_fd: %s: %s\n",
195
gpgme_strsource(rc), gpgme_strerror(rc));
199
rc = gpgme_op_import(mc.ctx, pgp_data);
200
if(rc != GPG_ERR_NO_ERROR){
201
fprintf(stderr, "bad gpgme_op_import: %s: %s\n",
202
gpgme_strsource(rc), gpgme_strerror(rc));
206
ret = (int)TEMP_FAILURE_RETRY(close(fd));
210
gpgme_data_release(pgp_data);
215
fprintf(stderr, "Initializing GPGME\n");
107
fprintf(stderr, "Trying to decrypt OpenPGP data\n");
219
111
gpgme_check_version(NULL);
220
112
rc = gpgme_engine_check_version(GPGME_PROTOCOL_OpenPGP);
221
if(rc != GPG_ERR_NO_ERROR){
113
if (rc != GPG_ERR_NO_ERROR){
222
114
fprintf(stderr, "bad gpgme_engine_check_version: %s: %s\n",
223
115
gpgme_strsource(rc), gpgme_strerror(rc));
227
/* Set GPGME home directory for the OpenPGP engine only */
228
rc = gpgme_get_engine_info(&engine_info);
229
if(rc != GPG_ERR_NO_ERROR){
119
/* Set GPGME home directory for the OpenPGP engine only */
120
rc = gpgme_get_engine_info (&engine_info);
121
if (rc != GPG_ERR_NO_ERROR){
230
122
fprintf(stderr, "bad gpgme_get_engine_info: %s: %s\n",
231
123
gpgme_strsource(rc), gpgme_strerror(rc));
234
126
while(engine_info != NULL){
235
127
if(engine_info->protocol == GPGME_PROTOCOL_OpenPGP){
236
128
gpgme_set_engine_info(GPGME_PROTOCOL_OpenPGP,
237
engine_info->file_name, tempdir);
129
engine_info->file_name, homedir);
240
132
engine_info = engine_info->next;
242
134
if(engine_info == NULL){
243
fprintf(stderr, "Could not set GPGME home dir to %s\n", tempdir);
247
/* Create new GPGME "context" */
248
rc = gpgme_new(&(mc.ctx));
249
if(rc != GPG_ERR_NO_ERROR){
250
fprintf(stderr, "bad gpgme_new: %s: %s\n",
251
gpgme_strsource(rc), gpgme_strerror(rc));
255
if(not import_key(pubkey) or not import_key(seckey)){
263
* Decrypt OpenPGP data.
264
* Returns -1 on error
266
static ssize_t pgp_packet_decrypt(const char *cryptotext,
269
gpgme_data_t dh_crypto, dh_plain;
272
size_t plaintext_capacity = 0;
273
ssize_t plaintext_length = 0;
276
fprintf(stderr, "Trying to decrypt OpenPGP data\n");
135
fprintf(stderr, "Could not set GPGME home dir to %s\n", homedir);
279
139
/* Create new GPGME data buffer from memory cryptotext */
280
140
rc = gpgme_data_new_from_mem(&dh_crypto, cryptotext, crypto_size,
282
if(rc != GPG_ERR_NO_ERROR){
142
if (rc != GPG_ERR_NO_ERROR){
283
143
fprintf(stderr, "bad gpgme_data_new_from_mem: %s: %s\n",
284
144
gpgme_strsource(rc), gpgme_strerror(rc));
385
260
return plaintext_length;
388
static const char * safer_gnutls_strerror(int value){
389
const char *ret = gnutls_strerror(value); /* Spurious warning from
390
-Wunreachable-code */
263
static const char * safer_gnutls_strerror (int value) {
264
const char *ret = gnutls_strerror (value);
392
266
ret = "(unknown)";
396
/* GnuTLS log function callback */
397
270
static void debuggnutls(__attribute__((unused)) int level,
398
271
const char* string){
399
fprintf(stderr, "GnuTLS: %s", string);
272
fprintf(stderr, "%s", string);
402
static int init_gnutls_global(const char *pubkeyfilename,
403
const char *seckeyfilename){
275
static int initgnutls(mandos_context *mc, gnutls_session_t *session,
276
gnutls_dh_params_t *dh_params){
407
281
fprintf(stderr, "Initializing GnuTLS\n");
410
ret = gnutls_global_init();
411
if(ret != GNUTLS_E_SUCCESS){
412
fprintf(stderr, "GnuTLS global_init: %s\n",
413
safer_gnutls_strerror(ret));
284
if ((ret = gnutls_global_init ())
285
!= GNUTLS_E_SUCCESS) {
286
fprintf (stderr, "global_init: %s\n", safer_gnutls_strerror(ret));
418
/* "Use a log level over 10 to enable all debugging options."
421
291
gnutls_global_set_log_level(11);
422
292
gnutls_global_set_log_function(debuggnutls);
425
/* OpenPGP credentials */
426
ret = gnutls_certificate_allocate_credentials(&mc.cred);
427
if(ret != GNUTLS_E_SUCCESS){
428
fprintf(stderr, "GnuTLS memory error: %s\n",
429
safer_gnutls_strerror(ret));
430
gnutls_global_deinit();
295
/* openpgp credentials */
296
if ((ret = gnutls_certificate_allocate_credentials (&mc->cred))
297
!= GNUTLS_E_SUCCESS) {
298
fprintf (stderr, "memory error: %s\n",
299
safer_gnutls_strerror(ret));
435
fprintf(stderr, "Attempting to use OpenPGP public key %s and"
436
" secret key %s as GnuTLS credentials\n", pubkeyfilename,
304
fprintf(stderr, "Attempting to use OpenPGP certificate %s"
305
" and keyfile %s as GnuTLS credentials\n", pubkeyfile,
440
309
ret = gnutls_certificate_set_openpgp_key_file
441
(mc.cred, pubkeyfilename, seckeyfilename,
442
GNUTLS_OPENPGP_FMT_BASE64);
443
if(ret != GNUTLS_E_SUCCESS){
445
"Error[%d] while reading the OpenPGP key pair ('%s',"
446
" '%s')\n", ret, pubkeyfilename, seckeyfilename);
447
fprintf(stderr, "The GnuTLS error is: %s\n",
448
safer_gnutls_strerror(ret));
452
/* GnuTLS server initialization */
453
ret = gnutls_dh_params_init(&mc.dh_params);
454
if(ret != GNUTLS_E_SUCCESS){
455
fprintf(stderr, "Error in GnuTLS DH parameter initialization:"
456
" %s\n", safer_gnutls_strerror(ret));
459
ret = gnutls_dh_params_generate2(mc.dh_params, mc.dh_bits);
460
if(ret != GNUTLS_E_SUCCESS){
461
fprintf(stderr, "Error in GnuTLS prime generation: %s\n",
462
safer_gnutls_strerror(ret));
466
gnutls_certificate_set_dh_params(mc.cred, mc.dh_params);
472
gnutls_certificate_free_credentials(mc.cred);
473
gnutls_global_deinit();
474
gnutls_dh_params_deinit(mc.dh_params);
478
static int init_gnutls_session(gnutls_session_t *session){
480
/* GnuTLS session creation */
482
ret = gnutls_init(session, GNUTLS_SERVER);
486
} while(ret == GNUTLS_E_INTERRUPTED or ret == GNUTLS_E_AGAIN);
487
if(ret != GNUTLS_E_SUCCESS){
310
(mc->cred, pubkeyfile, seckeyfile, GNUTLS_OPENPGP_FMT_BASE64);
311
if (ret != GNUTLS_E_SUCCESS) {
313
(stderr, "Error[%d] while reading the OpenPGP key pair ('%s',"
315
ret, pubkeyfile, seckeyfile);
316
fprintf(stdout, "The Error is: %s\n",
317
safer_gnutls_strerror(ret));
321
//GnuTLS server initialization
322
if ((ret = gnutls_dh_params_init(dh_params))
323
!= GNUTLS_E_SUCCESS) {
324
fprintf (stderr, "Error in dh parameter initialization: %s\n",
325
safer_gnutls_strerror(ret));
329
if ((ret = gnutls_dh_params_generate2(*dh_params, mc->dh_bits))
330
!= GNUTLS_E_SUCCESS) {
331
fprintf (stderr, "Error in prime generation: %s\n",
332
safer_gnutls_strerror(ret));
336
gnutls_certificate_set_dh_params(mc->cred, *dh_params);
338
// GnuTLS session creation
339
if ((ret = gnutls_init(session, GNUTLS_SERVER))
340
!= GNUTLS_E_SUCCESS){
488
341
fprintf(stderr, "Error in GnuTLS session initialization: %s\n",
489
342
safer_gnutls_strerror(ret));
495
ret = gnutls_priority_set_direct(*session, mc.priority, &err);
497
gnutls_deinit(*session);
500
} while(ret == GNUTLS_E_INTERRUPTED or ret == GNUTLS_E_AGAIN);
501
if(ret != GNUTLS_E_SUCCESS){
502
fprintf(stderr, "Syntax error at: %s\n", err);
503
fprintf(stderr, "GnuTLS error: %s\n",
504
safer_gnutls_strerror(ret));
505
gnutls_deinit(*session);
345
if ((ret = gnutls_priority_set_direct(*session, mc->priority, &err))
346
!= GNUTLS_E_SUCCESS) {
347
fprintf(stderr, "Syntax error at: %s\n", err);
348
fprintf(stderr, "GnuTLS error: %s\n",
349
safer_gnutls_strerror(ret));
511
ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,
514
gnutls_deinit(*session);
517
} while(ret == GNUTLS_E_INTERRUPTED or ret == GNUTLS_E_AGAIN);
518
if(ret != GNUTLS_E_SUCCESS){
519
fprintf(stderr, "Error setting GnuTLS credentials: %s\n",
353
if ((ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,
355
!= GNUTLS_E_SUCCESS) {
356
fprintf(stderr, "Error setting a credentials set: %s\n",
520
357
safer_gnutls_strerror(ret));
521
gnutls_deinit(*session);
525
361
/* ignore client certificate if any. */
526
gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);
362
gnutls_certificate_server_set_request (*session,
528
gnutls_dh_set_prime_bits(*session, mc.dh_bits);
365
gnutls_dh_set_prime_bits (*session, mc->dh_bits);
533
/* Avahi log function callback */
534
370
static void empty_log(__attribute__((unused)) AvahiLogLevel level,
535
371
__attribute__((unused)) const char *txt){}
537
/* Called when a Mandos server is found */
538
373
static int start_mandos_communication(const char *ip, uint16_t port,
539
374
AvahiIfIndex if_index,
541
int ret, tcp_sd = -1;
544
struct sockaddr_in in;
545
struct sockaddr_in6 in6;
377
struct sockaddr_in6 to;
547
378
char *buffer = NULL;
548
char *decrypted_buffer = NULL;
379
char *decrypted_buffer;
549
380
size_t buffer_length = 0;
550
381
size_t buffer_capacity = 0;
382
ssize_t decrypted_buffer_size;
385
char interface[IF_NAMESIZE];
553
386
gnutls_session_t session;
554
int pf; /* Protocol family */
571
fprintf(stderr, "Bad address family: %d\n", af);
576
ret = init_gnutls_session(&session);
387
gnutls_dh_params_t dh_params;
582
fprintf(stderr, "Setting up a TCP connection to %s, port %" PRIu16
390
fprintf(stderr, "Setting up a tcp connection to %s, port %d\n",
586
tcp_sd = socket(pf, SOCK_STREAM, 0);
394
tcp_sd = socket(PF_INET6, SOCK_STREAM, 0);
589
396
perror("socket");
599
memset(&to, 0, sizeof(to));
601
to.in6.sin6_family = (sa_family_t)af;
602
ret = inet_pton(af, ip, &to.in6.sin6_addr);
604
to.in.sin_family = (sa_family_t)af;
605
ret = inet_pton(af, ip, &to.in.sin_addr);
401
if(if_indextoname((unsigned int)if_index, interface) == NULL){
402
perror("if_indextoname");
405
fprintf(stderr, "Binding to interface %s\n", interface);
408
memset(&to,0,sizeof(to)); /* Spurious warning */
409
to.sin6_family = AF_INET6;
410
ret = inet_pton(AF_INET6, ip, &to.sin6_addr);
609
412
perror("inet_pton");
615
416
fprintf(stderr, "Bad address: %s\n", ip);
620
to.in6.sin6_port = htons(port); /* Spurious warnings from
622
-Wunreachable-code */
624
if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */
625
(&to.in6.sin6_addr)){ /* -Wstrict-aliasing=2 or lower and
627
if(if_index == AVAHI_IF_UNSPEC){
628
fprintf(stderr, "An IPv6 link-local address is incomplete"
629
" without a network interface\n");
633
/* Set the network interface number as scope */
634
to.in6.sin6_scope_id = (uint32_t)if_index;
637
to.in.sin_port = htons(port); /* Spurious warnings from
639
-Wunreachable-code */
419
to.sin6_port = htons(port); /* Spurious warning */
421
to.sin6_scope_id = (uint32_t)if_index;
648
if(af == AF_INET6 and if_index != AVAHI_IF_UNSPEC){
649
char interface[IF_NAMESIZE];
650
if(if_indextoname((unsigned int)if_index, interface) == NULL){
651
perror("if_indextoname");
653
fprintf(stderr, "Connection to: %s%%%s, port %" PRIu16 "\n",
654
ip, interface, port);
657
fprintf(stderr, "Connection to: %s, port %" PRIu16 "\n", ip,
660
char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?
661
INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";
664
pcret = inet_ntop(af, &(to.in6.sin6_addr), addrstr,
667
pcret = inet_ntop(af, &(to.in.sin_addr), addrstr,
424
fprintf(stderr, "Connection to: %s, port %d\n", ip, port);
425
char addrstr[INET6_ADDRSTRLEN] = "";
426
if(inet_ntop(to.sin6_family, &(to.sin6_addr), addrstr,
427
sizeof(addrstr)) == NULL){
671
428
perror("inet_ntop");
673
430
if(strcmp(addrstr, ip) != 0){
685
ret = connect(tcp_sd, &to.in6, sizeof(to));
687
ret = connect(tcp_sd, &to.in, sizeof(to)); /* IPv4 */
690
if ((errno != ECONNREFUSED and errno != ENETUNREACH) or debug){
703
const char *out = mandos_protocol_version;
706
size_t out_size = strlen(out);
707
ret = (int)TEMP_FAILURE_RETRY(write(tcp_sd, out + written,
708
out_size - written));
715
written += (size_t)ret;
716
if(written < out_size){
719
if(out == mandos_protocol_version){
436
ret = connect(tcp_sd, (struct sockaddr *) &to, sizeof(to));
442
ret = initgnutls (mc, &session, &dh_params);
448
gnutls_transport_set_ptr (session, (gnutls_transport_ptr_t) tcp_sd);
734
451
fprintf(stderr, "Establishing TLS session with %s\n", ip);
742
gnutls_transport_set_ptr(session, (gnutls_transport_ptr_t) tcp_sd);
750
ret = gnutls_handshake(session);
755
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
757
if(ret != GNUTLS_E_SUCCESS){
454
ret = gnutls_handshake (session);
456
if (ret != GNUTLS_E_SUCCESS){
759
fprintf(stderr, "*** GnuTLS Handshake failed ***\n");
458
fprintf(stderr, "\n*** Handshake failed ***\n");
766
/* Read OpenPGP packet that contains the wanted password */
465
//Retrieve OpenPGP packet that contains the wanted password
769
fprintf(stderr, "Retrieving OpenPGP encrypted password from %s\n",
468
fprintf(stderr, "Retrieving pgp encrypted password from %s\n",
780
buffer_capacity = incbuffer(&buffer, buffer_length,
782
if(buffer_capacity == 0){
794
sret = gnutls_record_recv(session, buffer+buffer_length,
473
if (buffer_length + BUFFER_SIZE > buffer_capacity){
474
buffer = realloc(buffer, buffer_capacity + BUFFER_SIZE);
479
buffer_capacity += BUFFER_SIZE;
482
ret = gnutls_record_recv(session, buffer+buffer_length,
801
489
case GNUTLS_E_INTERRUPTED:
802
490
case GNUTLS_E_AGAIN:
804
492
case GNUTLS_E_REHANDSHAKE:
806
ret = gnutls_handshake(session);
812
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
814
fprintf(stderr, "*** GnuTLS Re-handshake failed ***\n");
493
ret = gnutls_handshake (session);
495
fprintf(stderr, "\n*** Handshake failed ***\n");
821
502
fprintf(stderr, "Unknown error while reading data from"
822
" encrypted session with Mandos server\n");
823
gnutls_bye(session, GNUTLS_SHUT_RDWR);
503
" encrypted session with mandos server\n");
505
gnutls_bye (session, GNUTLS_SHUT_RDWR);
828
buffer_length += (size_t) sret;
833
fprintf(stderr, "Closing TLS session\n");
842
ret = gnutls_bye(session, GNUTLS_SHUT_RDWR);
847
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
849
if(buffer_length > 0){
850
ssize_t decrypted_buffer_size;
509
buffer_length += (size_t) ret;
513
if (buffer_length > 0){
851
514
decrypted_buffer_size = pgp_packet_decrypt(buffer,
854
if(decrypted_buffer_size >= 0){
518
if (decrypted_buffer_size >= 0){
857
519
while(written < (size_t) decrypted_buffer_size){
863
ret = (int)fwrite(decrypted_buffer + written, 1,
864
(size_t)decrypted_buffer_size - written,
520
ret = (int)fwrite (decrypted_buffer + written, 1,
521
(size_t)decrypted_buffer_size - written,
866
523
if(ret == 0 and ferror(stdout)){
869
525
fprintf(stderr, "Error writing encrypted data: %s\n",
870
526
strerror(errno));
875
531
written += (size_t)ret;
881
/* Shutdown procedure */
886
free(decrypted_buffer);
889
ret = (int)TEMP_FAILURE_RETRY(close(tcp_sd));
897
gnutls_deinit(session);
533
free(decrypted_buffer);
542
fprintf(stderr, "Closing TLS session\n");
546
gnutls_bye (session, GNUTLS_SHUT_RDWR);
549
gnutls_deinit (session);
550
gnutls_certificate_free_credentials (mc->cred);
551
gnutls_global_deinit ();
907
555
static void resolve_callback(AvahiSServiceResolver *r,
908
556
AvahiIfIndex interface,
557
AVAHI_GCC_UNUSED AvahiProtocol protocol,
910
558
AvahiResolverEvent event,
911
559
const char *name,
912
560
const char *type,
1001
642
case AVAHI_BROWSER_ALL_FOR_NOW:
1002
643
case AVAHI_BROWSER_CACHE_EXHAUSTED:
1004
fprintf(stderr, "No Mandos server found, still searching...\n");
1010
/* stop main loop after sigterm has been called */
1011
static void handle_sigterm(int sig){
1016
signal_received = sig;
1017
int old_errno = errno;
1018
if(mc.simple_poll != NULL){
1019
avahi_simple_poll_quit(mc.simple_poll);
1025
* This function determines if a directory entry in /sys/class/net
1026
* corresponds to an acceptable network device.
1027
* (This function is passed to scandir(3) as a filter function.)
1029
int good_interface(const struct dirent *if_entry){
1031
char *flagname = NULL;
1032
if(if_entry->d_name[0] == '.'){
1035
int ret = asprintf(&flagname, "%s/%s/flags", sys_class_net,
1041
int flags_fd = (int)TEMP_FAILURE_RETRY(open(flagname, O_RDONLY));
1048
typedef short ifreq_flags; /* ifreq.ifr_flags in netdevice(7) */
1049
/* read line from flags_fd */
1050
ssize_t to_read = 2+(sizeof(ifreq_flags)*2)+1; /* "0x1003\n" */
1051
char *flagstring = malloc((size_t)to_read+1); /* +1 for final \0 */
1052
flagstring[(size_t)to_read] = '\0';
1053
if(flagstring == NULL){
1059
ssret = (ssize_t)TEMP_FAILURE_RETRY(read(flags_fd, flagstring,
1076
tmpmax = strtoimax(flagstring, &tmp, 0);
1077
if(errno != 0 or tmp == flagstring or (*tmp != '\0'
1078
and not (isspace(*tmp)))
1079
or tmpmax != (ifreq_flags)tmpmax){
1081
fprintf(stderr, "Invalid flags \"%s\" for interface \"%s\"\n",
1082
flagstring, if_entry->d_name);
1088
ifreq_flags flags = (ifreq_flags)tmpmax;
1089
/* Reject the loopback device */
1090
if(flags & IFF_LOOPBACK){
1092
fprintf(stderr, "Rejecting loopback interface \"%s\"\n",
1097
/* Accept point-to-point devices only if connect_to is specified */
1098
if(connect_to != NULL and (flags & IFF_POINTOPOINT)){
1100
fprintf(stderr, "Accepting point-to-point interface \"%s\"\n",
1105
/* Otherwise, reject non-broadcast-capable devices */
1106
if(not (flags & IFF_BROADCAST)){
1108
fprintf(stderr, "Rejecting non-broadcast interface \"%s\"\n",
1113
/* Reject non-ARP interfaces (including dummy interfaces) */
1114
if(flags & IFF_NOARP){
1116
fprintf(stderr, "Rejecting non-ARP interface \"%s\"\n",
1121
/* Accept this device */
1123
fprintf(stderr, "Interface \"%s\" is acceptable\n",
1129
int main(int argc, char *argv[]){
1130
AvahiSServiceBrowser *sb = NULL;
1135
int exitcode = EXIT_SUCCESS;
1136
const char *interface = "";
1137
struct ifreq network;
1139
bool take_down_interface = false;
1142
char tempdir[] = "/tmp/mandosXXXXXX";
1143
bool tempdir_created = false;
1144
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
1145
const char *seckey = PATHDIR "/" SECKEY;
1146
const char *pubkey = PATHDIR "/" PUBKEY;
1148
bool gnutls_initialized = false;
1149
bool gpgme_initialized = false;
1152
struct sigaction old_sigterm_action = { .sa_handler = SIG_DFL };
1153
struct sigaction sigterm_action = { .sa_handler = handle_sigterm };
1158
/* Lower any group privileges we might have, just to be safe */
1165
/* Lower user privileges (temporarily) */
1177
struct argp_option options[] = {
1178
{ .name = "debug", .key = 128,
1179
.doc = "Debug mode", .group = 3 },
1180
{ .name = "connect", .key = 'c',
1181
.arg = "ADDRESS:PORT",
1182
.doc = "Connect directly to a specific Mandos server",
1184
{ .name = "interface", .key = 'i',
1186
.doc = "Network interface that will be used to search for"
1189
{ .name = "seckey", .key = 's',
1191
.doc = "OpenPGP secret key file base name",
1193
{ .name = "pubkey", .key = 'p',
1195
.doc = "OpenPGP public key file base name",
1197
{ .name = "dh-bits", .key = 129,
1199
.doc = "Bit length of the prime number used in the"
1200
" Diffie-Hellman key exchange",
1202
{ .name = "priority", .key = 130,
1204
.doc = "GnuTLS priority string for the TLS handshake",
1206
{ .name = "delay", .key = 131,
1208
.doc = "Maximum delay to wait for interface startup",
1211
* These reproduce what we would get without ARGP_NO_HELP
1213
{ .name = "help", .key = '?',
1214
.doc = "Give this help list", .group = -1 },
1215
{ .name = "usage", .key = -3,
1216
.doc = "Give a short usage message", .group = -1 },
1217
{ .name = "version", .key = 'V',
1218
.doc = "Print program version", .group = -1 },
648
/* Combines file name and path and returns the malloced new
649
string. some sane checks could/should be added */
650
static const char *combinepath(const char *first, const char *second){
651
size_t f_len = strlen(first);
652
size_t s_len = strlen(second);
653
char *tmp = malloc(f_len + s_len + 2);
658
memcpy(tmp, first, f_len); /* Spurious warning */
662
memcpy(tmp + f_len + 1, second, s_len); /* Spurious warning */
664
tmp[f_len + 1 + s_len] = '\0';
669
int main(AVAHI_GCC_UNUSED int argc, AVAHI_GCC_UNUSED char*argv[]) {
670
AvahiServerConfig config;
671
AvahiSServiceBrowser *sb = NULL;
675
int returncode = EXIT_SUCCESS;
676
const char *interface = "eth0";
677
struct ifreq network;
679
char *connect_to = NULL;
680
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
681
mandos_context mc = { .simple_poll = NULL, .server = NULL,
682
.dh_bits = 1024, .priority = "SECURE256"};
1222
error_t parse_opt(int key, char *arg,
1223
struct argp_state *state){
1226
case 128: /* --debug */
1229
case 'c': /* --connect */
1232
case 'i': /* --interface */
1235
case 's': /* --seckey */
1238
case 'p': /* --pubkey */
1241
case 129: /* --dh-bits */
1243
tmpmax = strtoimax(arg, &tmp, 10);
1244
if(errno != 0 or tmp == arg or *tmp != '\0'
1245
or tmpmax != (typeof(mc.dh_bits))tmpmax){
1246
argp_error(state, "Bad number of DH bits");
1248
mc.dh_bits = (typeof(mc.dh_bits))tmpmax;
1250
case 130: /* --priority */
1253
case 131: /* --delay */
1255
delay = strtof(arg, &tmp);
1256
if(errno != 0 or tmp == arg or *tmp != '\0'){
1257
argp_error(state, "Bad delay");
1261
* These reproduce what we would get without ARGP_NO_HELP
1263
case '?': /* --help */
1264
argp_state_help(state, state->out_stream,
1265
(ARGP_HELP_STD_HELP | ARGP_HELP_EXIT_ERR)
1266
& ~(unsigned int)ARGP_HELP_EXIT_OK);
1267
case -3: /* --usage */
1268
argp_state_help(state, state->out_stream,
1269
ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);
1270
case 'V': /* --version */
1271
fprintf(state->out_stream, "%s\n", argp_program_version);
1272
exit(argp_err_exit_status);
684
debug_int = debug ? 1 : 0;
686
struct option long_options[] = {
687
{"debug", no_argument, &debug_int, 1},
688
{"connect", required_argument, NULL, 'c'},
689
{"interface", required_argument, NULL, 'i'},
690
{"keydir", required_argument, NULL, 'd'},
691
{"seckey", required_argument, NULL, 's'},
692
{"pubkey", required_argument, NULL, 'p'},
693
{"dh-bits", required_argument, NULL, 'D'},
694
{"priority", required_argument, NULL, 'P'},
697
int option_index = 0;
698
ret = getopt_long (argc, argv, "i:", long_options,
725
mc.dh_bits = (unsigned int) strtol(optarg, NULL, 10);
732
mc.priority = optarg;
1275
return ARGP_ERR_UNKNOWN;
1280
struct argp argp = { .options = options, .parser = parse_opt,
1282
.doc = "Mandos client -- Get and decrypt"
1283
" passwords from a Mandos server" };
1284
ret = argp_parse(&argp, argc, argv,
1285
ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);
1292
perror("argp_parse");
1293
exitcode = EX_OSERR;
1296
exitcode = EX_USAGE;
1302
avahi_set_log_function(empty_log);
1305
if(interface[0] == '\0'){
1306
struct dirent **direntries;
1307
ret = scandir(sys_class_net, &direntries, good_interface,
1310
/* Pick the first good interface */
1311
interface = strdup(direntries[0]->d_name);
1313
fprintf(stderr, "Using interface \"%s\"\n", interface);
1315
if(interface == NULL){
1318
exitcode = EXIT_FAILURE;
1324
fprintf(stderr, "Could not find a network interface\n");
1325
exitcode = EXIT_FAILURE;
1330
/* Initialize Avahi early so avahi_simple_poll_quit() can be called
1331
from the signal handler */
1332
/* Initialize the pseudo-RNG for Avahi */
1333
srand((unsigned int) time(NULL));
1334
mc.simple_poll = avahi_simple_poll_new();
1335
if(mc.simple_poll == NULL){
1336
fprintf(stderr, "Avahi: Failed to create simple poll object.\n");
1337
exitcode = EX_UNAVAILABLE;
1341
sigemptyset(&sigterm_action.sa_mask);
1342
ret = sigaddset(&sigterm_action.sa_mask, SIGINT);
1344
perror("sigaddset");
1345
exitcode = EX_OSERR;
1348
ret = sigaddset(&sigterm_action.sa_mask, SIGHUP);
1350
perror("sigaddset");
1351
exitcode = EX_OSERR;
1354
ret = sigaddset(&sigterm_action.sa_mask, SIGTERM);
1356
perror("sigaddset");
1357
exitcode = EX_OSERR;
1360
/* Need to check if the handler is SIG_IGN before handling:
1361
| [[info:libc:Initial Signal Actions]] |
1362
| [[info:libc:Basic Signal Handling]] |
1364
ret = sigaction(SIGINT, NULL, &old_sigterm_action);
1366
perror("sigaction");
1369
if(old_sigterm_action.sa_handler != SIG_IGN){
1370
ret = sigaction(SIGINT, &sigterm_action, NULL);
1372
perror("sigaction");
1373
exitcode = EX_OSERR;
1377
ret = sigaction(SIGHUP, NULL, &old_sigterm_action);
1379
perror("sigaction");
1382
if(old_sigterm_action.sa_handler != SIG_IGN){
1383
ret = sigaction(SIGHUP, &sigterm_action, NULL);
1385
perror("sigaction");
1386
exitcode = EX_OSERR;
1390
ret = sigaction(SIGTERM, NULL, &old_sigterm_action);
1392
perror("sigaction");
1395
if(old_sigterm_action.sa_handler != SIG_IGN){
1396
ret = sigaction(SIGTERM, &sigterm_action, NULL);
1398
perror("sigaction");
1399
exitcode = EX_OSERR;
1404
/* If the interface is down, bring it up */
1405
if(strcmp(interface, "none") != 0){
739
debug = debug_int ? true : false;
741
pubkeyfile = combinepath(keydir, pubkeyfile);
742
if (pubkeyfile == NULL){
743
perror("combinepath");
744
returncode = EXIT_FAILURE;
748
seckeyfile = combinepath(keydir, seckeyfile);
749
if (seckeyfile == NULL){
750
perror("combinepath");
1406
754
if_index = (AvahiIfIndex) if_nametoindex(interface);
1407
755
if(if_index == 0){
1408
756
fprintf(stderr, "No such interface: \"%s\"\n", interface);
1409
exitcode = EX_UNAVAILABLE;
1417
/* Re-raise priviliges */
1425
/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO
1426
messages about the network interface to mess up the prompt */
1427
ret = klogctl(8, NULL, 5);
1428
bool restore_loglevel = true;
1430
restore_loglevel = false;
1433
#endif /* __linux__ */
760
if(connect_to != NULL){
761
/* Connect directly, do not use Zeroconf */
762
/* (Mainly meant for debugging) */
763
char *address = strrchr(connect_to, ':');
765
fprintf(stderr, "No colon in address\n");
769
uint16_t port = (uint16_t) strtol(address+1, NULL, 10);
771
perror("Bad port number");
775
address = connect_to;
776
ret = start_mandos_communication(address, port, if_index, &mc);
1435
784
sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1437
786
perror("socket");
1438
exitcode = EX_OSERR;
1440
if(restore_loglevel){
1441
ret = klogctl(7, NULL, 0);
1446
#endif /* __linux__ */
1447
/* Lower privileges */
787
returncode = EXIT_FAILURE;
1455
strcpy(network.ifr_name, interface);
790
strcpy(network.ifr_name, interface); /* Spurious warning */
1456
791
ret = ioctl(sd, SIOCGIFFLAGS, &network);
1458
794
perror("ioctl SIOCGIFFLAGS");
1460
if(restore_loglevel){
1461
ret = klogctl(7, NULL, 0);
1466
#endif /* __linux__ */
1467
exitcode = EX_OSERR;
1468
/* Lower privileges */
795
returncode = EXIT_FAILURE;
1476
798
if((network.ifr_flags & IFF_UP) == 0){
1477
799
network.ifr_flags |= IFF_UP;
1478
take_down_interface = true;
1479
800
ret = ioctl(sd, SIOCSIFFLAGS, &network);
1481
take_down_interface = false;
1482
perror("ioctl SIOCSIFFLAGS +IFF_UP");
1483
exitcode = EX_OSERR;
1485
if(restore_loglevel){
1486
ret = klogctl(7, NULL, 0);
1491
#endif /* __linux__ */
1492
/* Lower privileges */
1501
/* sleep checking until interface is running */
1502
for(int i=0; i < delay * 4; i++){
1503
ret = ioctl(sd, SIOCGIFFLAGS, &network);
1505
perror("ioctl SIOCGIFFLAGS");
1506
} else if(network.ifr_flags & IFF_RUNNING){
1509
struct timespec sleeptime = { .tv_nsec = 250000000 };
1510
ret = nanosleep(&sleeptime, NULL);
1511
if(ret == -1 and errno != EINTR){
1512
perror("nanosleep");
1515
if(not take_down_interface){
1516
/* We won't need the socket anymore */
1517
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1523
if(restore_loglevel){
1524
/* Restores kernel loglevel to default */
1525
ret = klogctl(7, NULL, 0);
1530
#endif /* __linux__ */
1531
/* Lower privileges */
1533
if(take_down_interface){
1534
/* Lower privileges */
1540
/* Lower privileges permanently */
1552
ret = init_gnutls_global(pubkey, seckey);
1554
fprintf(stderr, "init_gnutls_global failed\n");
1555
exitcode = EX_UNAVAILABLE;
1558
gnutls_initialized = true;
1565
tempdir_created = true;
1566
if(mkdtemp(tempdir) == NULL){
1567
tempdir_created = false;
1576
if(not init_gpgme(pubkey, seckey, tempdir)){
1577
fprintf(stderr, "init_gpgme failed\n");
1578
exitcode = EX_UNAVAILABLE;
1581
gpgme_initialized = true;
1588
if(connect_to != NULL){
1589
/* Connect directly, do not use Zeroconf */
1590
/* (Mainly meant for debugging) */
1591
char *address = strrchr(connect_to, ':');
1592
if(address == NULL){
1593
fprintf(stderr, "No colon in address\n");
1594
exitcode = EX_USAGE;
1604
tmpmax = strtoimax(address+1, &tmp, 10);
1605
if(errno != 0 or tmp == address+1 or *tmp != '\0'
1606
or tmpmax != (uint16_t)tmpmax){
1607
fprintf(stderr, "Bad port number\n");
1608
exitcode = EX_USAGE;
1616
port = (uint16_t)tmpmax;
1618
address = connect_to;
1619
/* Colon in address indicates IPv6 */
1621
if(strchr(address, ':') != NULL){
1631
while(not quit_now){
1632
ret = start_mandos_communication(address, port, if_index, af);
1633
if(quit_now or ret == 0){
1640
exitcode = EXIT_SUCCESS;
1651
AvahiServerConfig config;
1652
/* Do not publish any local Zeroconf records */
802
perror("ioctl SIOCSIFFLAGS");
803
returncode = EXIT_FAILURE;
810
avahi_set_log_function(empty_log);
813
/* Initialize the psuedo-RNG */
814
srand((unsigned int) time(NULL));
816
/* Allocate main loop object */
817
if (!(mc.simple_poll = avahi_simple_poll_new())) {
818
fprintf(stderr, "Failed to create simple poll object.\n");
819
returncode = EXIT_FAILURE;
823
/* Do not publish any local records */
1653
824
avahi_server_config_init(&config);
1654
825
config.publish_hinfo = 0;
1655
826
config.publish_addresses = 0;
1656
827
config.publish_workstation = 0;
1657
828
config.publish_domain = 0;
1659
830
/* Allocate a new server */
1660
mc.server = avahi_server_new(avahi_simple_poll_get
1661
(mc.simple_poll), &config, NULL,
831
mc.server=avahi_server_new(avahi_simple_poll_get(mc.simple_poll),
832
&config, NULL, NULL, &error);
1664
/* Free the Avahi configuration data */
834
/* Free the configuration data */
1665
835
avahi_server_config_free(&config);
1668
/* Check if creating the Avahi server object succeeded */
1669
if(mc.server == NULL){
1670
fprintf(stderr, "Failed to create Avahi server: %s\n",
1671
avahi_strerror(error));
1672
exitcode = EX_UNAVAILABLE;
1680
/* Create the Avahi service browser */
1681
sb = avahi_s_service_browser_new(mc.server, if_index,
1682
AVAHI_PROTO_UNSPEC, "_mandos._tcp",
1683
NULL, 0, browse_callback, NULL);
1685
fprintf(stderr, "Failed to create service browser: %s\n",
1686
avahi_strerror(avahi_server_errno(mc.server)));
1687
exitcode = EX_UNAVAILABLE;
1695
/* Run the main loop */
1698
fprintf(stderr, "Starting Avahi loop search\n");
1701
avahi_simple_poll_loop(mc.simple_poll);
1706
fprintf(stderr, "%s exiting\n", argv[0]);
1709
/* Cleanup things */
1711
avahi_s_service_browser_free(sb);
1713
if(mc.server != NULL)
1714
avahi_server_free(mc.server);
1716
if(mc.simple_poll != NULL)
1717
avahi_simple_poll_free(mc.simple_poll);
1719
if(gnutls_initialized){
1720
gnutls_certificate_free_credentials(mc.cred);
1721
gnutls_global_deinit();
1722
gnutls_dh_params_deinit(mc.dh_params);
1725
if(gpgme_initialized){
1726
gpgme_release(mc.ctx);
1729
/* Take down the network interface */
1730
if(take_down_interface){
1731
/* Re-raise priviliges */
1738
ret = ioctl(sd, SIOCGIFFLAGS, &network);
1740
perror("ioctl SIOCGIFFLAGS");
1741
} else if(network.ifr_flags & IFF_UP) {
1742
network.ifr_flags &= ~(short)IFF_UP; /* clear flag */
1743
ret = ioctl(sd, SIOCSIFFLAGS, &network);
1745
perror("ioctl SIOCSIFFLAGS -IFF_UP");
1748
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1752
/* Lower privileges permanently */
1761
/* Removes the temp directory used by GPGME */
1762
if(tempdir_created){
1764
struct dirent *direntry;
1765
d = opendir(tempdir);
1767
if(errno != ENOENT){
1772
direntry = readdir(d);
1773
if(direntry == NULL){
1776
/* Skip "." and ".." */
1777
if(direntry->d_name[0] == '.'
1778
and (direntry->d_name[1] == '\0'
1779
or (direntry->d_name[1] == '.'
1780
and direntry->d_name[2] == '\0'))){
1783
char *fullname = NULL;
1784
ret = asprintf(&fullname, "%s/%s", tempdir,
1790
ret = remove(fullname);
1792
fprintf(stderr, "remove(\"%s\"): %s\n", fullname,
1799
ret = rmdir(tempdir);
1800
if(ret == -1 and errno != ENOENT){
1806
sigemptyset(&old_sigterm_action.sa_mask);
1807
old_sigterm_action.sa_handler = SIG_DFL;
1808
ret = (int)TEMP_FAILURE_RETRY(sigaction(signal_received,
1809
&old_sigterm_action,
1812
perror("sigaction");
1815
ret = raise(signal_received);
1816
} while(ret != 0 and errno == EINTR);
1821
TEMP_FAILURE_RETRY(pause());
837
/* Check if creating the server object succeeded */
839
fprintf(stderr, "Failed to create server: %s\n",
840
avahi_strerror(error));
841
returncode = EXIT_FAILURE;
845
/* Create the service browser */
846
sb = avahi_s_service_browser_new(mc.server, if_index,
848
"_mandos._tcp", NULL, 0,
849
browse_callback, &mc);
851
fprintf(stderr, "Failed to create service browser: %s\n",
852
avahi_strerror(avahi_server_errno(mc.server)));
853
returncode = EXIT_FAILURE;
857
/* Run the main loop */
860
fprintf(stderr, "Starting avahi loop search\n");
863
avahi_simple_poll_loop(mc.simple_poll);
868
fprintf(stderr, "%s exiting\n", argv[0]);
873
avahi_s_service_browser_free(sb);
876
avahi_server_free(mc.server);
879
avahi_simple_poll_free(mc.simple_poll);