60
64
#include <string.h> /* memset */
61
65
#include <arpa/inet.h> /* inet_pton() */
62
66
#include <iso646.h> /* not */
67
#include <net/if.h> /* IF_NAMESIZE */
68
#include <argp.h> /* struct argp_option,
69
struct argp_state, struct argp,
65
72
#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"
76
75
#define BUFFER_SIZE 256
79
77
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 */
82
gnutls_session_t session;
85
AvahiSimplePoll *simple_poll;
83
87
gnutls_certificate_credentials_t cred;
84
89
gnutls_dh_params_t dh_params;
88
ssize_t pgp_packet_decrypt (char *packet, size_t packet_size,
89
char **new_packet, const char *homedir){
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){
90
116
gpgme_data_t dh_crypto, dh_plain;
94
ssize_t new_packet_capacity = 0;
95
ssize_t new_packet_length = 0;
120
size_t plaintext_capacity = 0;
121
ssize_t plaintext_length = 0;
96
122
gpgme_engine_info_t engine_info;
99
fprintf(stderr, "Trying to decrypt OpenPGP packet\n");
125
fprintf(stderr, "Trying to decrypt OpenPGP data\n");
103
129
gpgme_check_version(NULL);
104
gpgme_engine_check_version(GPGME_PROTOCOL_OpenPGP);
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));
106
/* Set GPGME home directory */
137
/* Set GPGME home directory for the OpenPGP engine only */
107
138
rc = gpgme_get_engine_info (&engine_info);
108
139
if (rc != GPG_ERR_NO_ERROR){
109
140
fprintf(stderr, "bad gpgme_get_engine_info: %s: %s\n",
244
void debuggnutls(__attribute__((unused)) int level,
246
fprintf(stderr, "%s", string);
285
/* GnuTLS log function callback */
286
static void debuggnutls(__attribute__((unused)) int level,
288
fprintf(stderr, "GnuTLS: %s", string);
249
int initgnutls(encrypted_session *es){
291
static int init_gnutls_global(mandos_context *mc,
292
const char *pubkeyfile,
293
const char *seckeyfile){
254
297
fprintf(stderr, "Initializing GnuTLS\n");
257
300
if ((ret = gnutls_global_init ())
258
301
!= GNUTLS_E_SUCCESS) {
259
fprintf (stderr, "global_init: %s\n", safer_gnutls_strerror(ret));
302
fprintf (stderr, "GnuTLS global_init: %s\n",
303
safer_gnutls_strerror(ret));
308
/* "Use a log level over 10 to enable all debugging options."
264
311
gnutls_global_set_log_level(11);
265
312
gnutls_global_set_log_function(debuggnutls);
268
/* openpgp credentials */
269
if ((ret = gnutls_certificate_allocate_credentials (&es->cred))
315
/* OpenPGP credentials */
316
if ((ret = gnutls_certificate_allocate_credentials (&mc->cred))
270
317
!= GNUTLS_E_SUCCESS) {
271
fprintf (stderr, "memory error: %s\n",
318
fprintf (stderr, "GnuTLS memory error: %s\n",
272
319
safer_gnutls_strerror(ret));
277
324
fprintf(stderr, "Attempting to use OpenPGP certificate %s"
278
" and keyfile %s as GnuTLS credentials\n", CERTFILE,
325
" and keyfile %s as GnuTLS credentials\n", pubkeyfile,
282
329
ret = gnutls_certificate_set_openpgp_key_file
283
(es->cred, CERTFILE, KEYFILE, GNUTLS_OPENPGP_FMT_BASE64);
330
(mc->cred, pubkeyfile, seckeyfile, GNUTLS_OPENPGP_FMT_BASE64);
284
331
if (ret != GNUTLS_E_SUCCESS) {
286
(stderr, "Error[%d] while reading the OpenPGP key pair ('%s',"
288
ret, CERTFILE, KEYFILE);
289
fprintf(stdout, "The Error is: %s\n",
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",
290
336
safer_gnutls_strerror(ret));
294
//GnuTLS server initialization
295
if ((ret = gnutls_dh_params_init (&es->dh_params))
296
!= GNUTLS_E_SUCCESS) {
297
fprintf (stderr, "Error in dh parameter initialization: %s\n",
298
safer_gnutls_strerror(ret));
302
if ((ret = gnutls_dh_params_generate2 (es->dh_params, DH_BITS))
303
!= GNUTLS_E_SUCCESS) {
304
fprintf (stderr, "Error in prime generation: %s\n",
305
safer_gnutls_strerror(ret));
309
gnutls_certificate_set_dh_params (es->cred, es->dh_params);
311
// GnuTLS session creation
312
if ((ret = gnutls_init (&es->session, GNUTLS_SERVER))
313
!= GNUTLS_E_SUCCESS){
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){
314
365
fprintf(stderr, "Error in GnuTLS session initialization: %s\n",
315
366
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));
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));
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",
380
ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,
382
if (ret != GNUTLS_E_SUCCESS) {
383
fprintf(stderr, "Error setting GnuTLS credentials: %s\n",
330
384
safer_gnutls_strerror(ret));
334
388
/* ignore client certificate if any. */
335
gnutls_certificate_server_set_request (es->session,
389
gnutls_certificate_server_set_request (*session,
336
390
GNUTLS_CERT_IGNORE);
338
gnutls_dh_set_prime_bits (es->session, DH_BITS);
392
gnutls_dh_set_prime_bits (*session, mc->dh_bits);
343
void empty_log(__attribute__((unused)) AvahiLogLevel level,
344
__attribute__((unused)) const char *txt){}
397
/* Avahi log function callback */
398
static void empty_log(__attribute__((unused)) AvahiLogLevel level,
399
__attribute__((unused)) const char *txt){}
346
int start_mandos_communication(const char *ip, uint16_t port,
347
unsigned int if_index){
401
/* Called when a Mandos server is found */
402
static int start_mandos_communication(const char *ip, uint16_t port,
403
AvahiIfIndex if_index,
349
struct sockaddr_in6 to;
350
encrypted_session es;
406
union { struct sockaddr in; struct sockaddr_in6 in6; } to;
351
407
char *buffer = NULL;
352
408
char *decrypted_buffer;
353
409
size_t buffer_length = 0;
354
410
size_t buffer_capacity = 0;
355
411
ssize_t decrypted_buffer_size;
358
414
char interface[IF_NAMESIZE];
415
gnutls_session_t session;
417
ret = init_gnutls_session (mc, &session);
361
fprintf(stderr, "Setting up a tcp connection to %s\n", ip);
423
fprintf(stderr, "Setting up a tcp connection to %s, port %d\n",
364
427
tcp_sd = socket(PF_INET6, SOCK_STREAM, 0);
366
429
perror("socket");
370
if(if_indextoname(if_index, interface) == NULL){
434
if(if_indextoname((unsigned int)if_index, interface) == NULL){
372
435
perror("if_indextoname");
378
438
fprintf(stderr, "Binding to interface %s\n", interface);
381
441
memset(&to,0,sizeof(to)); /* Spurious warning */
382
to.sin6_family = AF_INET6;
383
ret = inet_pton(AF_INET6, ip, &to.sin6_addr);
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);
385
447
perror("inet_pton");
389
451
fprintf(stderr, "Bad address: %s\n", ip);
392
to.sin6_port = htons(port); /* Spurious warning */
454
to.in6.sin6_port = htons(port); /* Spurious warning */
394
to.sin6_scope_id = (uint32_t)if_index;
456
to.in6.sin6_scope_id = (uint32_t)if_index;
397
fprintf(stderr, "Connection to: %s\n", ip);
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);
400
ret = connect(tcp_sd, (struct sockaddr *) &to, sizeof(to));
471
ret = connect(tcp_sd, &to.in, sizeof(to));
402
473
perror("connect");
406
ret = initgnutls (&es);
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){
412
gnutls_transport_set_ptr (es.session,
413
(gnutls_transport_ptr_t) tcp_sd);
416
502
fprintf(stderr, "Establishing TLS session with %s\n", ip);
419
ret = gnutls_handshake (es.session);
505
gnutls_transport_set_ptr (session, (gnutls_transport_ptr_t) tcp_sd);
507
ret = gnutls_handshake (session);
421
509
if (ret != GNUTLS_E_SUCCESS){
422
fprintf(stderr, "\n*** Handshake failed ***\n");
511
fprintf(stderr, "*** GnuTLS Handshake failed ***\n");
428
//Retrieve OpenPGP packet that contains the wanted password
518
/* Read OpenPGP packet that contains the wanted password */
431
521
fprintf(stderr, "Retrieving pgp encrypted password from %s\n",
551
639
char ip[AVAHI_ADDRESS_STR_MAX];
552
640
avahi_address_snprint(ip, sizeof(ip), address);
554
fprintf(stderr, "Mandos server found on %s (%s) on port %d\n",
555
host_name, ip, port);
642
fprintf(stderr, "Mandos server \"%s\" found on %s (%s, %d) on"
643
" port %d\n", name, host_name, ip, interface, port);
557
int ret = start_mandos_communication(ip, port,
558
(unsigned int) interface);
645
int ret = start_mandos_communication(ip, port, interface, mc);
560
647
exit(EXIT_SUCCESS);
566
651
avahi_s_service_resolver_free(r);
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:
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");
618
int main(AVAHI_GCC_UNUSED int argc, AVAHI_GCC_UNUSED char*argv[]) {
619
AvahiServerConfig config;
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[]){
620
727
AvahiSServiceBrowser *sb = NULL;
623
int returncode = EXIT_SUCCESS;
730
int exitcode = EXIT_SUCCESS;
624
731
const char *interface = "eth0";
627
static struct option long_options[] = {
628
{"debug", no_argument, (int *)&debug, 1},
629
{"interface", required_argument, 0, 'i'},
632
int option_index = 0;
633
ret = getopt_long (argc, argv, "i:", long_options,
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;
652
923
avahi_set_log_function(empty_log);
655
/* Initialize the psuedo-RNG */
926
/* Initialize the pseudo-RNG for Avahi */
656
927
srand((unsigned int) time(NULL));
658
/* Allocate main loop object */
659
if (!(simple_poll = avahi_simple_poll_new())) {
660
fprintf(stderr, "Failed to create simple poll object.\n");
665
/* Do not publish any local records */
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",
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",
682
959
avahi_strerror(error));
683
returncode = EXIT_FAILURE;
960
exitcode = EXIT_FAILURE;
687
/* Create the service browser */
688
sb = avahi_s_service_browser_new(server,
690
if_nametoindex(interface),
964
/* Create the Avahi service browser */
965
sb = avahi_s_service_browser_new(mc.server, if_index,
691
966
AVAHI_PROTO_INET6,
692
967
"_mandos._tcp", NULL, 0,
693
browse_callback, server);
968
browse_callback, &mc);
695
970
fprintf(stderr, "Failed to create service browser: %s\n",
696
avahi_strerror(avahi_server_errno(server)));
697
returncode = EXIT_FAILURE;
971
avahi_strerror(avahi_server_errno(mc.server)));
972
exitcode = EXIT_FAILURE;
701
976
/* Run the main loop */
704
fprintf(stderr, "Starting avahi loop search\n");
979
fprintf(stderr, "Starting Avahi loop search\n");
707
avahi_simple_poll_loop(simple_poll);
982
avahi_simple_poll_loop(mc.simple_poll);
712
987
fprintf(stderr, "%s exiting\n", argv[0]);
715
990
/* Cleanup things */
717
992
avahi_s_service_browser_free(sb);
720
avahi_server_free(server);
723
avahi_simple_poll_free(simple_poll);
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);