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
static const char mandos_protocol_version[] = "1";
80
const char *argp_program_version = "mandosclient 0.9";
81
const char *argp_program_bug_address = "<mandos@fukt.bsnet.se>";
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){
94
* Make room in "buffer" for at least BUFFER_SIZE additional bytes.
95
* "buffer_capacity" is how much is currently allocated,
96
* "buffer_length" is how much is already used.
98
size_t adjustbuffer(char **buffer, size_t buffer_length,
99
size_t buffer_capacity){
100
if (buffer_length + BUFFER_SIZE > buffer_capacity){
101
*buffer = realloc(*buffer, buffer_capacity + BUFFER_SIZE);
105
buffer_capacity += BUFFER_SIZE;
107
return buffer_capacity;
111
* Decrypt OpenPGP data using keyrings in HOMEDIR.
112
* Returns -1 on error
114
static ssize_t pgp_packet_decrypt (const char *cryptotext,
117
const char *homedir){
90
118
gpgme_data_t dh_crypto, dh_plain;
94
ssize_t new_packet_capacity = 0;
95
ssize_t new_packet_length = 0;
122
size_t plaintext_capacity = 0;
123
ssize_t plaintext_length = 0;
96
124
gpgme_engine_info_t engine_info;
99
fprintf(stderr, "Trying to decrypt OpenPGP packet\n");
127
fprintf(stderr, "Trying to decrypt OpenPGP data\n");
103
131
gpgme_check_version(NULL);
104
gpgme_engine_check_version(GPGME_PROTOCOL_OpenPGP);
132
rc = gpgme_engine_check_version(GPGME_PROTOCOL_OpenPGP);
133
if (rc != GPG_ERR_NO_ERROR){
134
fprintf(stderr, "bad gpgme_engine_check_version: %s: %s\n",
135
gpgme_strsource(rc), gpgme_strerror(rc));
106
/* Set GPGME home directory */
139
/* Set GPGME home directory for the OpenPGP engine only */
107
140
rc = gpgme_get_engine_info (&engine_info);
108
141
if (rc != GPG_ERR_NO_ERROR){
109
142
fprintf(stderr, "bad gpgme_get_engine_info: %s: %s\n",
244
void debuggnutls(__attribute__((unused)) int level,
246
fprintf(stderr, "%s", string);
287
/* GnuTLS log function callback */
288
static void debuggnutls(__attribute__((unused)) int level,
290
fprintf(stderr, "GnuTLS: %s", string);
249
int initgnutls(encrypted_session *es){
293
static int init_gnutls_global(mandos_context *mc,
294
const char *pubkeyfile,
295
const char *seckeyfile){
254
299
fprintf(stderr, "Initializing GnuTLS\n");
257
302
if ((ret = gnutls_global_init ())
258
303
!= GNUTLS_E_SUCCESS) {
259
fprintf (stderr, "global_init: %s\n", safer_gnutls_strerror(ret));
304
fprintf (stderr, "GnuTLS global_init: %s\n",
305
safer_gnutls_strerror(ret));
310
/* "Use a log level over 10 to enable all debugging options."
264
313
gnutls_global_set_log_level(11);
265
314
gnutls_global_set_log_function(debuggnutls);
268
/* openpgp credentials */
269
if ((ret = gnutls_certificate_allocate_credentials (&es->cred))
317
/* OpenPGP credentials */
318
if ((ret = gnutls_certificate_allocate_credentials (&mc->cred))
270
319
!= GNUTLS_E_SUCCESS) {
271
fprintf (stderr, "memory error: %s\n",
320
fprintf (stderr, "GnuTLS memory error: %s\n",
272
321
safer_gnutls_strerror(ret));
322
gnutls_global_deinit ();
277
327
fprintf(stderr, "Attempting to use OpenPGP certificate %s"
278
" and keyfile %s as GnuTLS credentials\n", CERTFILE,
328
" and keyfile %s as GnuTLS credentials\n", pubkeyfile,
282
332
ret = gnutls_certificate_set_openpgp_key_file
283
(es->cred, CERTFILE, KEYFILE, GNUTLS_OPENPGP_FMT_BASE64);
333
(mc->cred, pubkeyfile, seckeyfile, GNUTLS_OPENPGP_FMT_BASE64);
284
334
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",
336
"Error[%d] while reading the OpenPGP key pair ('%s',"
337
" '%s')\n", ret, pubkeyfile, seckeyfile);
338
fprintf(stdout, "The GnuTLS error is: %s\n",
290
339
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){
343
/* GnuTLS server initialization */
344
ret = gnutls_dh_params_init(&mc->dh_params);
345
if (ret != GNUTLS_E_SUCCESS) {
346
fprintf (stderr, "Error in GnuTLS DH parameter initialization:"
347
" %s\n", safer_gnutls_strerror(ret));
350
ret = gnutls_dh_params_generate2(mc->dh_params, mc->dh_bits);
351
if (ret != GNUTLS_E_SUCCESS) {
352
fprintf (stderr, "Error in GnuTLS prime generation: %s\n",
353
safer_gnutls_strerror(ret));
357
gnutls_certificate_set_dh_params(mc->cred, mc->dh_params);
363
gnutls_certificate_free_credentials (mc->cred);
364
gnutls_global_deinit ();
369
static int init_gnutls_session(mandos_context *mc,
370
gnutls_session_t *session){
372
/* GnuTLS session creation */
373
ret = gnutls_init(session, GNUTLS_SERVER);
374
if (ret != GNUTLS_E_SUCCESS){
314
375
fprintf(stderr, "Error in GnuTLS session initialization: %s\n",
315
376
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));
381
ret = gnutls_priority_set_direct(*session, mc->priority, &err);
382
if (ret != GNUTLS_E_SUCCESS) {
383
fprintf(stderr, "Syntax error at: %s\n", err);
384
fprintf(stderr, "GnuTLS error: %s\n",
385
safer_gnutls_strerror(ret));
386
gnutls_deinit (*session);
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",
391
ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,
393
if (ret != GNUTLS_E_SUCCESS) {
394
fprintf(stderr, "Error setting GnuTLS credentials: %s\n",
330
395
safer_gnutls_strerror(ret));
396
gnutls_deinit (*session);
334
400
/* ignore client certificate if any. */
335
gnutls_certificate_server_set_request (es->session,
401
gnutls_certificate_server_set_request (*session,
336
402
GNUTLS_CERT_IGNORE);
338
gnutls_dh_set_prime_bits (es->session, DH_BITS);
404
gnutls_dh_set_prime_bits (*session, mc->dh_bits);
343
void empty_log(__attribute__((unused)) AvahiLogLevel level,
344
__attribute__((unused)) const char *txt){}
409
/* Avahi log function callback */
410
static void empty_log(__attribute__((unused)) AvahiLogLevel level,
411
__attribute__((unused)) const char *txt){}
346
int start_mandos_communication(const char *ip, uint16_t port,
347
unsigned int if_index){
413
/* Called when a Mandos server is found */
414
static int start_mandos_communication(const char *ip, uint16_t port,
415
AvahiIfIndex if_index,
349
struct sockaddr_in6 to;
350
encrypted_session es;
418
union { struct sockaddr in; struct sockaddr_in6 in6; } to;
351
419
char *buffer = NULL;
352
420
char *decrypted_buffer;
353
421
size_t buffer_length = 0;
354
422
size_t buffer_capacity = 0;
355
423
ssize_t decrypted_buffer_size;
358
426
char interface[IF_NAMESIZE];
427
gnutls_session_t session;
429
ret = init_gnutls_session (mc, &session);
361
fprintf(stderr, "Setting up a tcp connection to %s\n", ip);
435
fprintf(stderr, "Setting up a tcp connection to %s, port %d\n",
364
439
tcp_sd = socket(PF_INET6, SOCK_STREAM, 0);
366
441
perror("socket");
370
if(if_indextoname(if_index, interface) == NULL){
446
if(if_indextoname((unsigned int)if_index, interface) == NULL){
372
447
perror("if_indextoname");
378
450
fprintf(stderr, "Binding to interface %s\n", interface);
381
453
memset(&to,0,sizeof(to)); /* Spurious warning */
382
to.sin6_family = AF_INET6;
383
ret = inet_pton(AF_INET6, ip, &to.sin6_addr);
454
to.in6.sin6_family = AF_INET6;
455
/* It would be nice to have a way to detect if we were passed an
456
IPv4 address here. Now we assume an IPv6 address. */
457
ret = inet_pton(AF_INET6, ip, &to.in6.sin6_addr);
385
459
perror("inet_pton");
389
463
fprintf(stderr, "Bad address: %s\n", ip);
392
to.sin6_port = htons(port); /* Spurious warning */
466
to.in6.sin6_port = htons(port); /* Spurious warning */
394
to.sin6_scope_id = (uint32_t)if_index;
468
to.in6.sin6_scope_id = (uint32_t)if_index;
397
fprintf(stderr, "Connection to: %s\n", ip);
471
fprintf(stderr, "Connection to: %s, port %d\n", ip, port);
472
char addrstr[INET6_ADDRSTRLEN] = "";
473
if(inet_ntop(to.in6.sin6_family, &(to.in6.sin6_addr), addrstr,
474
sizeof(addrstr)) == NULL){
477
if(strcmp(addrstr, ip) != 0){
478
fprintf(stderr, "Canonical address form: %s\n", addrstr);
400
ret = connect(tcp_sd, (struct sockaddr *) &to, sizeof(to));
483
ret = connect(tcp_sd, &to.in, sizeof(to));
402
485
perror("connect");
406
ret = initgnutls (&es);
489
const char *out = mandos_protocol_version;
492
size_t out_size = strlen(out);
493
ret = TEMP_FAILURE_RETRY(write(tcp_sd, out + written,
494
out_size - written));
500
written += (size_t)ret;
501
if(written < out_size){
504
if (out == mandos_protocol_version){
412
gnutls_transport_set_ptr (es.session,
413
(gnutls_transport_ptr_t) tcp_sd);
416
514
fprintf(stderr, "Establishing TLS session with %s\n", ip);
419
ret = gnutls_handshake (es.session);
517
gnutls_transport_set_ptr (session, (gnutls_transport_ptr_t) tcp_sd);
519
ret = gnutls_handshake (session);
421
521
if (ret != GNUTLS_E_SUCCESS){
423
fprintf(stderr, "\n*** Handshake failed ***\n");
523
fprintf(stderr, "*** GnuTLS Handshake failed ***\n");
424
524
gnutls_perror (ret);
430
//Retrieve OpenPGP packet that contains the wanted password
530
/* Read OpenPGP packet that contains the wanted password */
433
533
fprintf(stderr, "Retrieving pgp encrypted password from %s\n",
566
661
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:
664
static void browse_callback( AvahiSServiceBrowser *b,
665
AvahiIfIndex interface,
666
AvahiProtocol protocol,
667
AvahiBrowserEvent event,
671
AVAHI_GCC_UNUSED AvahiLookupResultFlags
674
mandos_context *mc = userdata;
675
assert(b); /* Spurious warning */
677
/* Called whenever a new services becomes available on the LAN or
678
is removed from the LAN */
682
case AVAHI_BROWSER_FAILURE:
684
fprintf(stderr, "(Avahi browser) %s\n",
685
avahi_strerror(avahi_server_errno(mc->server)));
686
avahi_simple_poll_quit(mc->simple_poll);
689
case AVAHI_BROWSER_NEW:
690
/* We ignore the returned Avahi resolver object. In the callback
691
function we free it. If the Avahi server is terminated before
692
the callback function is called the Avahi server will free the
695
if (!(avahi_s_service_resolver_new(mc->server, interface,
696
protocol, name, type, domain,
697
AVAHI_PROTO_INET6, 0,
698
resolve_callback, mc)))
699
fprintf(stderr, "Avahi: Failed to resolve service '%s': %s\n",
700
name, avahi_strerror(avahi_server_errno(mc->server)));
703
case AVAHI_BROWSER_REMOVE:
706
case AVAHI_BROWSER_ALL_FOR_NOW:
707
case AVAHI_BROWSER_CACHE_EXHAUSTED:
709
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;
715
/* Combines file name and path and returns the malloced new
716
string. some sane checks could/should be added */
717
static const char *combinepath(const char *first, const char *second){
718
size_t f_len = strlen(first);
719
size_t s_len = strlen(second);
720
char *tmp = malloc(f_len + s_len + 2);
725
memcpy(tmp, first, f_len); /* Spurious warning */
729
memcpy(tmp + f_len + 1, second, s_len); /* Spurious warning */
731
tmp[f_len + 1 + s_len] = '\0';
736
int main(int argc, char *argv[]){
620
737
AvahiSServiceBrowser *sb = NULL;
623
int returncode = EXIT_SUCCESS;
740
int exitcode = EXIT_SUCCESS;
624
741
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,
742
struct ifreq network;
746
char *connect_to = NULL;
747
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
748
const char *pubkeyfile = "pubkey.txt";
749
const char *seckeyfile = "seckey.txt";
750
mandos_context mc = { .simple_poll = NULL, .server = NULL,
751
.dh_bits = 1024, .priority = "SECURE256"};
752
bool gnutls_initalized = false;
755
struct argp_option options[] = {
756
{ .name = "debug", .key = 128,
757
.doc = "Debug mode", .group = 3 },
758
{ .name = "connect", .key = 'c',
760
.doc = "Connect directly to a sepcified mandos server",
762
{ .name = "interface", .key = 'i',
764
.doc = "Interface that Avahi will conntect through",
766
{ .name = "keydir", .key = 'd',
768
.doc = "Directory where the openpgp keyring is",
770
{ .name = "seckey", .key = 's',
772
.doc = "Secret openpgp key for gnutls authentication",
774
{ .name = "pubkey", .key = 'p',
776
.doc = "Public openpgp key for gnutls authentication",
778
{ .name = "dh-bits", .key = 129,
780
.doc = "dh-bits to use in gnutls communication",
782
{ .name = "priority", .key = 130,
784
.doc = "GNUTLS priority", .group = 1 },
789
error_t parse_opt (int key, char *arg,
790
struct argp_state *state) {
791
/* Get the INPUT argument from `argp_parse', which we know is
792
a pointer to our plugin list pointer. */
814
mc.dh_bits = (unsigned int) strtol(arg, NULL, 10);
829
return ARGP_ERR_UNKNOWN;
834
struct argp argp = { .options = options, .parser = parse_opt,
836
.doc = "Mandos client -- Get and decrypt"
837
" passwords from mandos server" };
838
argp_parse (&argp, argc, argv, 0, 0, NULL);
841
pubkeyfile = combinepath(keydir, pubkeyfile);
842
if (pubkeyfile == NULL){
843
perror("combinepath");
844
exitcode = EXIT_FAILURE;
848
seckeyfile = combinepath(keydir, seckeyfile);
849
if (seckeyfile == NULL){
850
perror("combinepath");
854
ret = init_gnutls_global(&mc, pubkeyfile, seckeyfile);
856
fprintf(stderr, "init_gnutls_global\n");
859
gnutls_initalized = true;
875
if_index = (AvahiIfIndex) if_nametoindex(interface);
877
fprintf(stderr, "No such interface: \"%s\"\n", interface);
881
if(connect_to != NULL){
882
/* Connect directly, do not use Zeroconf */
883
/* (Mainly meant for debugging) */
884
char *address = strrchr(connect_to, ':');
886
fprintf(stderr, "No colon in address\n");
887
exitcode = EXIT_FAILURE;
891
uint16_t port = (uint16_t) strtol(address+1, NULL, 10);
893
perror("Bad port number");
894
exitcode = EXIT_FAILURE;
898
address = connect_to;
899
ret = start_mandos_communication(address, port, if_index, &mc);
901
exitcode = EXIT_FAILURE;
903
exitcode = EXIT_SUCCESS;
908
/* If the interface is down, bring it up */
910
sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
913
exitcode = EXIT_FAILURE;
916
strcpy(network.ifr_name, interface); /* Spurious warning */
917
ret = ioctl(sd, SIOCGIFFLAGS, &network);
919
perror("ioctl SIOCGIFFLAGS");
920
exitcode = EXIT_FAILURE;
923
if((network.ifr_flags & IFF_UP) == 0){
924
network.ifr_flags |= IFF_UP;
925
ret = ioctl(sd, SIOCSIFFLAGS, &network);
927
perror("ioctl SIOCSIFFLAGS");
928
exitcode = EXIT_FAILURE;
652
936
avahi_set_log_function(empty_log);
655
/* Initialize the psuedo-RNG */
939
/* Initialize the pseudo-RNG for Avahi */
656
940
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",
942
/* Allocate main Avahi loop object */
943
mc.simple_poll = avahi_simple_poll_new();
944
if (mc.simple_poll == NULL) {
945
fprintf(stderr, "Avahi: Failed to create simple poll"
947
exitcode = EXIT_FAILURE;
952
AvahiServerConfig config;
953
/* Do not publish any local Zeroconf records */
954
avahi_server_config_init(&config);
955
config.publish_hinfo = 0;
956
config.publish_addresses = 0;
957
config.publish_workstation = 0;
958
config.publish_domain = 0;
960
/* Allocate a new server */
961
mc.server = avahi_server_new(avahi_simple_poll_get
962
(mc.simple_poll), &config, NULL,
965
/* Free the Avahi configuration data */
966
avahi_server_config_free(&config);
969
/* Check if creating the Avahi server object succeeded */
970
if (mc.server == NULL) {
971
fprintf(stderr, "Failed to create Avahi server: %s\n",
682
972
avahi_strerror(error));
683
returncode = EXIT_FAILURE;
973
exitcode = EXIT_FAILURE;
687
/* Create the service browser */
688
sb = avahi_s_service_browser_new(server,
690
if_nametoindex(interface),
977
/* Create the Avahi service browser */
978
sb = avahi_s_service_browser_new(mc.server, if_index,
691
979
AVAHI_PROTO_INET6,
692
980
"_mandos._tcp", NULL, 0,
693
browse_callback, server);
981
browse_callback, &mc);
695
983
fprintf(stderr, "Failed to create service browser: %s\n",
696
avahi_strerror(avahi_server_errno(server)));
697
returncode = EXIT_FAILURE;
984
avahi_strerror(avahi_server_errno(mc.server)));
985
exitcode = EXIT_FAILURE;
701
989
/* Run the main loop */
704
fprintf(stderr, "Starting avahi loop search\n");
992
fprintf(stderr, "Starting Avahi loop search\n");
707
avahi_simple_poll_loop(simple_poll);
995
avahi_simple_poll_loop(mc.simple_poll);
712
1000
fprintf(stderr, "%s exiting\n", argv[0]);
715
1003
/* Cleanup things */
717
1005
avahi_s_service_browser_free(sb);
720
avahi_server_free(server);
723
avahi_simple_poll_free(simple_poll);
1007
if (mc.server != NULL)
1008
avahi_server_free(mc.server);
1010
if (mc.simple_poll != NULL)
1011
avahi_simple_poll_free(mc.simple_poll);
1015
if (gnutls_initalized){
1016
gnutls_certificate_free_credentials (mc.cred);
1017
gnutls_global_deinit ();