64
60
#include <string.h> /* memset */
65
61
#include <arpa/inet.h> /* inet_pton() */
66
62
#include <iso646.h> /* not */
67
#include <net/if.h> /* IF_NAMESIZE */
68
#include <argp.h> /* struct argp_option,
69
struct argp_state, struct argp,
72
65
#include <errno.h> /* perror() */
72
#define CERT_ROOT "/conf/conf.d/cryptkeyreq/"
74
#define CERTFILE CERT_ROOT "openpgp-client.txt"
75
#define KEYFILE CERT_ROOT "openpgp-client-key.txt"
75
76
#define BUFFER_SIZE 256
77
79
bool debug = false;
78
static const char *keydir = "/conf/conf.d/mandos";
79
const char *argp_program_version = "mandosclient 0.9";
80
const char *argp_program_bug_address = "<mandos@fukt.bsnet.se>";
81
static const char mandos_protocol_version[] = "1";
83
/* Used for passing in values through the Avahi callback functions */
85
AvahiSimplePoll *simple_poll;
82
gnutls_session_t session;
87
83
gnutls_certificate_credentials_t cred;
89
84
gnutls_dh_params_t dh_params;
93
/* Make room in "buffer" for at least BUFFER_SIZE additional bytes.
94
* "buffer_capacity" is how much is currently allocated,
95
* "buffer_length" is how much is already used. */
96
size_t adjustbuffer(char **buffer, size_t buffer_length,
97
size_t buffer_capacity){
98
if (buffer_length + BUFFER_SIZE > buffer_capacity){
99
*buffer = realloc(*buffer, buffer_capacity + BUFFER_SIZE);
103
buffer_capacity += BUFFER_SIZE;
105
return buffer_capacity;
109
* Decrypt OpenPGP data using keyrings in HOMEDIR.
110
* Returns -1 on error
112
static ssize_t pgp_packet_decrypt (const char *cryptotext,
115
const char *homedir){
88
ssize_t pgp_packet_decrypt (char *packet, size_t packet_size,
89
char **new_packet, const char *homedir){
116
90
gpgme_data_t dh_crypto, dh_plain;
120
size_t plaintext_capacity = 0;
121
ssize_t plaintext_length = 0;
94
ssize_t new_packet_capacity = 0;
95
ssize_t new_packet_length = 0;
122
96
gpgme_engine_info_t engine_info;
125
fprintf(stderr, "Trying to decrypt OpenPGP data\n");
99
fprintf(stderr, "Trying to decrypt OpenPGP packet\n");
129
103
gpgme_check_version(NULL);
130
rc = gpgme_engine_check_version(GPGME_PROTOCOL_OpenPGP);
131
if (rc != GPG_ERR_NO_ERROR){
132
fprintf(stderr, "bad gpgme_engine_check_version: %s: %s\n",
133
gpgme_strsource(rc), gpgme_strerror(rc));
104
gpgme_engine_check_version(GPGME_PROTOCOL_OpenPGP);
137
/* Set GPGME home directory for the OpenPGP engine only */
106
/* Set GPGME home directory */
138
107
rc = gpgme_get_engine_info (&engine_info);
139
108
if (rc != GPG_ERR_NO_ERROR){
140
109
fprintf(stderr, "bad gpgme_get_engine_info: %s: %s\n",
285
/* GnuTLS log function callback */
286
static void debuggnutls(__attribute__((unused)) int level,
288
fprintf(stderr, "GnuTLS: %s", string);
244
void debuggnutls(__attribute__((unused)) int level,
246
fprintf(stderr, "%s", string);
291
static int init_gnutls_global(mandos_context *mc,
292
const char *pubkeyfile,
293
const char *seckeyfile){
249
int initgnutls(encrypted_session *es){
297
254
fprintf(stderr, "Initializing GnuTLS\n");
300
257
if ((ret = gnutls_global_init ())
301
258
!= GNUTLS_E_SUCCESS) {
302
fprintf (stderr, "GnuTLS global_init: %s\n",
303
safer_gnutls_strerror(ret));
259
fprintf (stderr, "global_init: %s\n", safer_gnutls_strerror(ret));
308
/* "Use a log level over 10 to enable all debugging options."
311
264
gnutls_global_set_log_level(11);
312
265
gnutls_global_set_log_function(debuggnutls);
315
/* OpenPGP credentials */
316
if ((ret = gnutls_certificate_allocate_credentials (&mc->cred))
268
/* openpgp credentials */
269
if ((ret = gnutls_certificate_allocate_credentials (&es->cred))
317
270
!= GNUTLS_E_SUCCESS) {
318
fprintf (stderr, "GnuTLS memory error: %s\n",
271
fprintf (stderr, "memory error: %s\n",
319
272
safer_gnutls_strerror(ret));
324
277
fprintf(stderr, "Attempting to use OpenPGP certificate %s"
325
" and keyfile %s as GnuTLS credentials\n", pubkeyfile,
278
" and keyfile %s as GnuTLS credentials\n", CERTFILE,
329
282
ret = gnutls_certificate_set_openpgp_key_file
330
(mc->cred, pubkeyfile, seckeyfile, GNUTLS_OPENPGP_FMT_BASE64);
283
(es->cred, CERTFILE, KEYFILE, GNUTLS_OPENPGP_FMT_BASE64);
331
284
if (ret != GNUTLS_E_SUCCESS) {
333
"Error[%d] while reading the OpenPGP key pair ('%s',"
334
" '%s')\n", ret, pubkeyfile, seckeyfile);
335
fprintf(stdout, "The GnuTLS error is: %s\n",
286
(stderr, "Error[%d] while reading the OpenPGP key pair ('%s',"
288
ret, CERTFILE, KEYFILE);
289
fprintf(stdout, "The Error is: %s\n",
336
290
safer_gnutls_strerror(ret));
340
/* GnuTLS server initialization */
341
ret = gnutls_dh_params_init(&mc->dh_params);
342
if (ret != GNUTLS_E_SUCCESS) {
343
fprintf (stderr, "Error in GnuTLS DH parameter initialization:"
344
" %s\n", safer_gnutls_strerror(ret));
347
ret = gnutls_dh_params_generate2(mc->dh_params, mc->dh_bits);
348
if (ret != GNUTLS_E_SUCCESS) {
349
fprintf (stderr, "Error in GnuTLS prime generation: %s\n",
350
safer_gnutls_strerror(ret));
354
gnutls_certificate_set_dh_params(mc->cred, mc->dh_params);
359
static int init_gnutls_session(mandos_context *mc,
360
gnutls_session_t *session){
362
/* GnuTLS session creation */
363
ret = gnutls_init(session, GNUTLS_SERVER);
364
if (ret != GNUTLS_E_SUCCESS){
294
//GnuTLS server initialization
295
if ((ret = gnutls_dh_params_init (&es->dh_params))
296
!= GNUTLS_E_SUCCESS) {
297
fprintf (stderr, "Error in dh parameter initialization: %s\n",
298
safer_gnutls_strerror(ret));
302
if ((ret = gnutls_dh_params_generate2 (es->dh_params, DH_BITS))
303
!= GNUTLS_E_SUCCESS) {
304
fprintf (stderr, "Error in prime generation: %s\n",
305
safer_gnutls_strerror(ret));
309
gnutls_certificate_set_dh_params (es->cred, es->dh_params);
311
// GnuTLS session creation
312
if ((ret = gnutls_init (&es->session, GNUTLS_SERVER))
313
!= GNUTLS_E_SUCCESS){
365
314
fprintf(stderr, "Error in GnuTLS session initialization: %s\n",
366
315
safer_gnutls_strerror(ret));
371
ret = gnutls_priority_set_direct(*session, mc->priority, &err);
372
if (ret != GNUTLS_E_SUCCESS) {
373
fprintf(stderr, "Syntax error at: %s\n", err);
374
fprintf(stderr, "GnuTLS error: %s\n",
375
safer_gnutls_strerror(ret));
318
if ((ret = gnutls_priority_set_direct (es->session, "NORMAL", &err))
319
!= GNUTLS_E_SUCCESS) {
320
fprintf(stderr, "Syntax error at: %s\n", err);
321
fprintf(stderr, "GnuTLS error: %s\n",
322
safer_gnutls_strerror(ret));
380
ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,
382
if (ret != GNUTLS_E_SUCCESS) {
383
fprintf(stderr, "Error setting GnuTLS credentials: %s\n",
326
if ((ret = gnutls_credentials_set
327
(es->session, GNUTLS_CRD_CERTIFICATE, es->cred))
328
!= GNUTLS_E_SUCCESS) {
329
fprintf(stderr, "Error setting a credentials set: %s\n",
384
330
safer_gnutls_strerror(ret));
388
334
/* ignore client certificate if any. */
389
gnutls_certificate_server_set_request (*session,
335
gnutls_certificate_server_set_request (es->session,
390
336
GNUTLS_CERT_IGNORE);
392
gnutls_dh_set_prime_bits (*session, mc->dh_bits);
338
gnutls_dh_set_prime_bits (es->session, DH_BITS);
397
/* Avahi log function callback */
398
static void empty_log(__attribute__((unused)) AvahiLogLevel level,
399
__attribute__((unused)) const char *txt){}
343
void empty_log(__attribute__((unused)) AvahiLogLevel level,
344
__attribute__((unused)) const char *txt){}
401
/* Called when a Mandos server is found */
402
static int start_mandos_communication(const char *ip, uint16_t port,
403
AvahiIfIndex if_index,
346
int start_mandos_communication(const char *ip, uint16_t port,
347
unsigned int if_index){
406
union { struct sockaddr in; struct sockaddr_in6 in6; } to;
349
struct sockaddr_in6 to;
350
encrypted_session es;
407
351
char *buffer = NULL;
408
352
char *decrypted_buffer;
409
353
size_t buffer_length = 0;
410
354
size_t buffer_capacity = 0;
411
355
ssize_t decrypted_buffer_size;
414
358
char interface[IF_NAMESIZE];
415
gnutls_session_t session;
417
ret = init_gnutls_session (mc, &session);
423
fprintf(stderr, "Setting up a tcp connection to %s, port %d\n",
361
fprintf(stderr, "Setting up a tcp connection to %s\n", ip);
427
364
tcp_sd = socket(PF_INET6, SOCK_STREAM, 0);
429
366
perror("socket");
434
if(if_indextoname((unsigned int)if_index, interface) == NULL){
370
if(if_indextoname(if_index, interface) == NULL){
435
372
perror("if_indextoname");
438
378
fprintf(stderr, "Binding to interface %s\n", interface);
441
381
memset(&to,0,sizeof(to)); /* Spurious warning */
442
to.in6.sin6_family = AF_INET6;
443
/* It would be nice to have a way to detect if we were passed an
444
IPv4 address here. Now we assume an IPv6 address. */
445
ret = inet_pton(AF_INET6, ip, &to.in6.sin6_addr);
382
to.sin6_family = AF_INET6;
383
ret = inet_pton(AF_INET6, ip, &to.sin6_addr);
447
385
perror("inet_pton");
451
389
fprintf(stderr, "Bad address: %s\n", ip);
454
to.in6.sin6_port = htons(port); /* Spurious warning */
392
to.sin6_port = htons(port); /* Spurious warning */
456
to.in6.sin6_scope_id = (uint32_t)if_index;
394
to.sin6_scope_id = (uint32_t)if_index;
459
fprintf(stderr, "Connection to: %s, port %d\n", ip, port);
460
char addrstr[INET6_ADDRSTRLEN] = "";
461
if(inet_ntop(to.in6.sin6_family, &(to.in6.sin6_addr), addrstr,
462
sizeof(addrstr)) == NULL){
465
if(strcmp(addrstr, ip) != 0){
466
fprintf(stderr, "Canonical address form: %s\n", addrstr);
397
fprintf(stderr, "Connection to: %s\n", ip);
471
ret = connect(tcp_sd, &to.in, sizeof(to));
400
ret = connect(tcp_sd, (struct sockaddr *) &to, sizeof(to));
473
402
perror("connect");
477
const char *out = mandos_protocol_version;
480
size_t out_size = strlen(out);
481
ret = TEMP_FAILURE_RETRY(write(tcp_sd, out + written,
482
out_size - written));
488
written += (size_t)ret;
489
if(written < out_size){
492
if (out == mandos_protocol_version){
406
ret = initgnutls (&es);
412
gnutls_transport_set_ptr (es.session,
413
(gnutls_transport_ptr_t) tcp_sd);
502
416
fprintf(stderr, "Establishing TLS session with %s\n", ip);
505
gnutls_transport_set_ptr (session, (gnutls_transport_ptr_t) tcp_sd);
507
ret = gnutls_handshake (session);
419
ret = gnutls_handshake (es.session);
509
421
if (ret != GNUTLS_E_SUCCESS){
511
fprintf(stderr, "*** GnuTLS Handshake failed ***\n");
422
fprintf(stderr, "\n*** Handshake failed ***\n");
518
/* Read OpenPGP packet that contains the wanted password */
428
//Retrieve OpenPGP packet that contains the wanted password
521
431
fprintf(stderr, "Retrieving pgp encrypted password from %s\n",
639
551
char ip[AVAHI_ADDRESS_STR_MAX];
640
552
avahi_address_snprint(ip, sizeof(ip), address);
642
fprintf(stderr, "Mandos server \"%s\" found on %s (%s, %d) on"
643
" port %d\n", name, host_name, ip, interface, port);
554
fprintf(stderr, "Mandos server found on %s (%s) on port %d\n",
555
host_name, ip, port);
645
int ret = start_mandos_communication(ip, port, interface, mc);
557
int ret = start_mandos_communication(ip, port,
558
(unsigned int) interface);
647
560
exit(EXIT_SUCCESS);
651
566
avahi_s_service_resolver_free(r);
654
static void browse_callback( AvahiSServiceBrowser *b,
655
AvahiIfIndex interface,
656
AvahiProtocol protocol,
657
AvahiBrowserEvent event,
661
AVAHI_GCC_UNUSED AvahiLookupResultFlags
664
mandos_context *mc = userdata;
665
assert(b); /* Spurious warning */
667
/* Called whenever a new services becomes available on the LAN or
668
is removed from the LAN */
672
case AVAHI_BROWSER_FAILURE:
674
fprintf(stderr, "(Avahi browser) %s\n",
675
avahi_strerror(avahi_server_errno(mc->server)));
676
avahi_simple_poll_quit(mc->simple_poll);
679
case AVAHI_BROWSER_NEW:
680
/* We ignore the returned Avahi resolver object. In the callback
681
function we free it. If the Avahi server is terminated before
682
the callback function is called the Avahi server will free the
685
if (!(avahi_s_service_resolver_new(mc->server, interface,
686
protocol, name, type, domain,
687
AVAHI_PROTO_INET6, 0,
688
resolve_callback, mc)))
689
fprintf(stderr, "Avahi: Failed to resolve service '%s': %s\n",
690
name, avahi_strerror(avahi_server_errno(mc->server)));
693
case AVAHI_BROWSER_REMOVE:
696
case AVAHI_BROWSER_ALL_FOR_NOW:
697
case AVAHI_BROWSER_CACHE_EXHAUSTED:
699
fprintf(stderr, "No Mandos server found, still searching...\n");
569
static void browse_callback(
570
AvahiSServiceBrowser *b,
571
AvahiIfIndex interface,
572
AvahiProtocol protocol,
573
AvahiBrowserEvent event,
577
AVAHI_GCC_UNUSED AvahiLookupResultFlags flags,
580
AvahiServer *s = userdata;
581
assert(b); /* Spurious warning */
583
/* Called whenever a new services becomes available on the LAN or
584
is removed from the LAN */
588
case AVAHI_BROWSER_FAILURE:
590
fprintf(stderr, "(Browser) %s\n",
591
avahi_strerror(avahi_server_errno(server)));
592
avahi_simple_poll_quit(simple_poll);
595
case AVAHI_BROWSER_NEW:
596
/* We ignore the returned resolver object. In the callback
597
function we free it. If the server is terminated before
598
the callback function is called the server will free
599
the resolver for us. */
601
if (!(avahi_s_service_resolver_new(s, interface, protocol, name,
603
AVAHI_PROTO_INET6, 0,
604
resolve_callback, s)))
605
fprintf(stderr, "Failed to resolve service '%s': %s\n", name,
606
avahi_strerror(avahi_server_errno(s)));
609
case AVAHI_BROWSER_REMOVE:
612
case AVAHI_BROWSER_ALL_FOR_NOW:
613
case AVAHI_BROWSER_CACHE_EXHAUSTED:
705
/* Combines file name and path and returns the malloced new
706
string. some sane checks could/should be added */
707
static const char *combinepath(const char *first, const char *second){
708
size_t f_len = strlen(first);
709
size_t s_len = strlen(second);
710
char *tmp = malloc(f_len + s_len + 2);
715
memcpy(tmp, first, f_len); /* Spurious warning */
719
memcpy(tmp + f_len + 1, second, s_len); /* Spurious warning */
721
tmp[f_len + 1 + s_len] = '\0';
726
int main(int argc, char *argv[]){
618
int main(AVAHI_GCC_UNUSED int argc, AVAHI_GCC_UNUSED char*argv[]) {
619
AvahiServerConfig config;
727
620
AvahiSServiceBrowser *sb = NULL;
730
int exitcode = EXIT_SUCCESS;
623
int returncode = EXIT_SUCCESS;
731
624
const char *interface = "eth0";
732
struct ifreq network;
736
char *connect_to = NULL;
737
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
738
const char *pubkeyfile = "pubkey.txt";
739
const char *seckeyfile = "seckey.txt";
740
mandos_context mc = { .simple_poll = NULL, .server = NULL,
741
.dh_bits = 1024, .priority = "SECURE256"};
744
struct argp_option options[] = {
745
{ .name = "debug", .key = 128,
746
.doc = "Debug mode", .group = 3 },
747
{ .name = "connect", .key = 'c',
749
.doc = "Connect directly to a sepcified mandos server",
751
{ .name = "interface", .key = 'i',
753
.doc = "Interface that Avahi will conntect through",
755
{ .name = "keydir", .key = 'd',
757
.doc = "Directory where the openpgp keyring is",
759
{ .name = "seckey", .key = 's',
761
.doc = "Secret openpgp key for gnutls authentication",
763
{ .name = "pubkey", .key = 'p',
765
.doc = "Public openpgp key for gnutls authentication",
767
{ .name = "dh-bits", .key = 129,
769
.doc = "dh-bits to use in gnutls communication",
771
{ .name = "priority", .key = 130,
773
.doc = "GNUTLS priority", .group = 1 },
778
error_t parse_opt (int key, char *arg,
779
struct argp_state *state) {
780
/* Get the INPUT argument from `argp_parse', which we know is
781
a pointer to our plugin list pointer. */
803
mc.dh_bits = (unsigned int) strtol(arg, NULL, 10);
818
return ARGP_ERR_UNKNOWN;
823
struct argp argp = { .options = options, .parser = parse_opt,
825
.doc = "Mandos client -- Get and decrypt"
826
" passwords from mandos server" };
827
argp_parse (&argp, argc, argv, 0, 0, NULL);
830
pubkeyfile = combinepath(keydir, pubkeyfile);
831
if (pubkeyfile == NULL){
832
perror("combinepath");
833
exitcode = EXIT_FAILURE;
837
seckeyfile = combinepath(keydir, seckeyfile);
838
if (seckeyfile == NULL){
839
perror("combinepath");
843
ret = init_gnutls_global(&mc, pubkeyfile, seckeyfile);
845
fprintf(stderr, "init_gnutls_global\n");
862
if_index = (AvahiIfIndex) if_nametoindex(interface);
864
fprintf(stderr, "No such interface: \"%s\"\n", interface);
868
if(connect_to != NULL){
869
/* Connect directly, do not use Zeroconf */
870
/* (Mainly meant for debugging) */
871
char *address = strrchr(connect_to, ':');
873
fprintf(stderr, "No colon in address\n");
874
exitcode = EXIT_FAILURE;
878
uint16_t port = (uint16_t) strtol(address+1, NULL, 10);
880
perror("Bad port number");
881
exitcode = EXIT_FAILURE;
885
address = connect_to;
886
ret = start_mandos_communication(address, port, if_index, &mc);
888
exitcode = EXIT_FAILURE;
890
exitcode = EXIT_SUCCESS;
895
/* If the interface is down, bring it up */
897
sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
900
exitcode = EXIT_FAILURE;
903
strcpy(network.ifr_name, interface); /* Spurious warning */
904
ret = ioctl(sd, SIOCGIFFLAGS, &network);
906
perror("ioctl SIOCGIFFLAGS");
907
exitcode = EXIT_FAILURE;
910
if((network.ifr_flags & IFF_UP) == 0){
911
network.ifr_flags |= IFF_UP;
912
ret = ioctl(sd, SIOCSIFFLAGS, &network);
914
perror("ioctl SIOCSIFFLAGS");
915
exitcode = EXIT_FAILURE;
627
static struct option long_options[] = {
628
{"debug", no_argument, (int *)&debug, 1},
629
{"interface", required_argument, 0, 'i'},
632
int option_index = 0;
633
ret = getopt_long (argc, argv, "i:", long_options,
923
652
avahi_set_log_function(empty_log);
926
/* Initialize the pseudo-RNG for Avahi */
655
/* Initialize the psuedo-RNG */
927
656
srand((unsigned int) time(NULL));
929
/* Allocate main Avahi loop object */
930
mc.simple_poll = avahi_simple_poll_new();
931
if (mc.simple_poll == NULL) {
932
fprintf(stderr, "Avahi: Failed to create simple poll"
934
exitcode = EXIT_FAILURE;
939
AvahiServerConfig config;
940
/* Do not publish any local Zeroconf records */
941
avahi_server_config_init(&config);
942
config.publish_hinfo = 0;
943
config.publish_addresses = 0;
944
config.publish_workstation = 0;
945
config.publish_domain = 0;
947
/* Allocate a new server */
948
mc.server = avahi_server_new(avahi_simple_poll_get
949
(mc.simple_poll), &config, NULL,
952
/* Free the Avahi configuration data */
953
avahi_server_config_free(&config);
956
/* Check if creating the Avahi server object succeeded */
957
if (mc.server == NULL) {
958
fprintf(stderr, "Failed to create Avahi server: %s\n",
658
/* Allocate main loop object */
659
if (!(simple_poll = avahi_simple_poll_new())) {
660
fprintf(stderr, "Failed to create simple poll object.\n");
665
/* Do not publish any local records */
666
avahi_server_config_init(&config);
667
config.publish_hinfo = 0;
668
config.publish_addresses = 0;
669
config.publish_workstation = 0;
670
config.publish_domain = 0;
672
/* Allocate a new server */
673
server = avahi_server_new(avahi_simple_poll_get(simple_poll),
674
&config, NULL, NULL, &error);
676
/* Free the configuration data */
677
avahi_server_config_free(&config);
679
/* Check if creating the server object succeeded */
681
fprintf(stderr, "Failed to create server: %s\n",
959
682
avahi_strerror(error));
960
exitcode = EXIT_FAILURE;
683
returncode = EXIT_FAILURE;
964
/* Create the Avahi service browser */
965
sb = avahi_s_service_browser_new(mc.server, if_index,
687
/* Create the service browser */
688
sb = avahi_s_service_browser_new(server,
690
if_nametoindex(interface),
966
691
AVAHI_PROTO_INET6,
967
692
"_mandos._tcp", NULL, 0,
968
browse_callback, &mc);
693
browse_callback, server);
970
695
fprintf(stderr, "Failed to create service browser: %s\n",
971
avahi_strerror(avahi_server_errno(mc.server)));
972
exitcode = EXIT_FAILURE;
696
avahi_strerror(avahi_server_errno(server)));
697
returncode = EXIT_FAILURE;
976
701
/* Run the main loop */
979
fprintf(stderr, "Starting Avahi loop search\n");
704
fprintf(stderr, "Starting avahi loop search\n");
982
avahi_simple_poll_loop(mc.simple_poll);
707
avahi_simple_poll_loop(simple_poll);
987
712
fprintf(stderr, "%s exiting\n", argv[0]);
990
715
/* Cleanup things */
992
717
avahi_s_service_browser_free(sb);
994
if (mc.server != NULL)
995
avahi_server_free(mc.server);
997
if (mc.simple_poll != NULL)
998
avahi_simple_poll_free(mc.simple_poll);
720
avahi_server_free(server);
723
avahi_simple_poll_free(simple_poll);