32
32
#define _LARGEFILE_SOURCE
33
33
#define _FILE_OFFSET_BITS 64
35
#define _GNU_SOURCE /* TEMP_FAILURE_RETRY() */
35
#define _GNU_SOURCE /* TEMP_FAILURE_RETRY(), asprintf() */
41
#include <net/if.h> /* if_nametoindex */
42
#include <sys/ioctl.h> /* ioctl, ifreq, SIOCGIFFLAGS, IFF_UP,
37
#include <stdio.h> /* fprintf(), stderr, fwrite(),
39
#include <stdint.h> /* uint16_t, uint32_t */
40
#include <stddef.h> /* NULL, size_t, ssize_t */
41
#include <stdlib.h> /* free(), EXIT_SUCCESS, EXIT_FAILURE,
43
#include <stdbool.h> /* bool, true */
44
#include <string.h> /* memset(), strcmp(), strlen(),
45
strerror(), asprintf(), strcpy() */
46
#include <sys/ioctl.h> /* ioctl */
47
#include <sys/types.h> /* socket(), inet_pton(), sockaddr,
48
sockaddr_in6, PF_INET6,
49
SOCK_STREAM, INET6_ADDRSTRLEN,
50
uid_t, gid_t, open(), opendir(), DIR */
51
#include <sys/stat.h> /* open() */
52
#include <sys/socket.h> /* socket(), struct sockaddr_in6,
53
struct in6_addr, inet_pton(),
55
#include <fcntl.h> /* open() */
56
#include <dirent.h> /* opendir(), struct dirent, readdir() */
57
#include <inttypes.h> /* PRIu16 */
58
#include <assert.h> /* assert() */
59
#include <errno.h> /* perror(), errno */
60
#include <time.h> /* time() */
44
61
#include <net/if.h> /* ioctl, ifreq, SIOCGIFFLAGS, IFF_UP,
62
SIOCSIFFLAGS, if_indextoname(),
63
if_nametoindex(), IF_NAMESIZE */
64
#include <netinet/in.h>
65
#include <unistd.h> /* close(), SEEK_SET, off_t, write(),
66
getuid(), getgid(), setuid(),
68
#include <arpa/inet.h> /* inet_pton(), htons */
69
#include <iso646.h> /* not, and */
70
#include <argp.h> /* struct argp_option, error_t, struct
71
argp_state, struct argp,
72
argp_parse(), ARGP_KEY_ARG,
73
ARGP_KEY_END, ARGP_ERR_UNKNOWN */
76
/* All Avahi types, constants and functions
47
79
#include <avahi-core/core.h>
48
80
#include <avahi-core/lookup.h>
49
81
#include <avahi-core/log.h>
51
83
#include <avahi-common/malloc.h>
52
84
#include <avahi-common/error.h>
54
/* Mandos client part */
55
#include <sys/types.h> /* socket(), inet_pton() */
56
#include <sys/socket.h> /* socket(), struct sockaddr_in6,
57
struct in6_addr, inet_pton() */
58
#include <gnutls/gnutls.h> /* All GnuTLS stuff */
59
#include <gnutls/openpgp.h> /* GnuTLS with openpgp stuff */
87
#include <gnutls/gnutls.h> /* All GnuTLS types, constants and
90
init_gnutls_session(),
92
#include <gnutls/openpgp.h> /* gnutls_certificate_set_openpgp_key_file(),
93
GNUTLS_OPENPGP_FMT_BASE64 */
61
#include <unistd.h> /* close() */
62
#include <netinet/in.h>
63
#include <stdbool.h> /* true */
64
#include <string.h> /* memset */
65
#include <arpa/inet.h> /* inet_pton() */
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,
72
#include <errno.h> /* perror() */
96
#include <gpgme.h> /* All GPGME types, constants and
99
GPGME_PROTOCOL_OpenPGP,
75
102
#define BUFFER_SIZE 256
105
#define PATHDIR "/conf/conf.d/mandos"
108
#define PATHDIR "/conf/conf.d/mandos"
109
#define SECKEY "seckey.txt"
110
#define PUBKEY "pupkey.txt"
77
112
bool debug = false;
78
static const char *keydir = "/conf/conf.d/mandos";
79
113
static const char mandos_protocol_version[] = "1";
80
const char *argp_program_version = "mandosclient 0.9";
114
const char *argp_program_version = "password-request 1.0";
81
115
const char *argp_program_bug_address = "<mandos@fukt.bsnet.se>";
83
117
/* Used for passing in values through the Avahi callback functions */
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){
118
gpgme_data_t dh_crypto, dh_plain;
148
static bool init_gpgme(mandos_context *mc, const char *seckey,
149
const char *pubkey, const char *tempdir){
120
151
gpgme_error_t rc;
122
size_t plaintext_capacity = 0;
123
ssize_t plaintext_length = 0;
124
152
gpgme_engine_info_t engine_info;
156
* Helper function to insert pub and seckey to the enigne keyring.
158
bool import_key(const char *filename){
160
gpgme_data_t pgp_data;
162
fd = TEMP_FAILURE_RETRY(open(filename, O_RDONLY));
168
rc = gpgme_data_new_from_fd(&pgp_data, fd);
169
if (rc != GPG_ERR_NO_ERROR){
170
fprintf(stderr, "bad gpgme_data_new_from_fd: %s: %s\n",
171
gpgme_strsource(rc), gpgme_strerror(rc));
175
rc = gpgme_op_import(mc->ctx, pgp_data);
176
if (rc != GPG_ERR_NO_ERROR){
177
fprintf(stderr, "bad gpgme_op_import: %s: %s\n",
178
gpgme_strsource(rc), gpgme_strerror(rc));
182
ret = TEMP_FAILURE_RETRY(close(fd));
186
gpgme_data_release(pgp_data);
127
fprintf(stderr, "Trying to decrypt OpenPGP data\n");
191
fprintf(stderr, "Initialize gpgme\n");
131
195
gpgme_check_version(NULL);
132
196
rc = gpgme_engine_check_version(GPGME_PROTOCOL_OpenPGP);
133
197
if (rc != GPG_ERR_NO_ERROR){
134
198
fprintf(stderr, "bad gpgme_engine_check_version: %s: %s\n",
135
199
gpgme_strsource(rc), gpgme_strerror(rc));
139
/* Set GPGME home directory for the OpenPGP engine only */
203
/* Set GPGME home directory for the OpenPGP engine only */
140
204
rc = gpgme_get_engine_info (&engine_info);
141
205
if (rc != GPG_ERR_NO_ERROR){
142
206
fprintf(stderr, "bad gpgme_get_engine_info: %s: %s\n",
143
207
gpgme_strsource(rc), gpgme_strerror(rc));
146
210
while(engine_info != NULL){
147
211
if(engine_info->protocol == GPGME_PROTOCOL_OpenPGP){
148
212
gpgme_set_engine_info(GPGME_PROTOCOL_OpenPGP,
149
engine_info->file_name, homedir);
213
engine_info->file_name, tempdir);
152
216
engine_info = engine_info->next;
154
218
if(engine_info == NULL){
155
fprintf(stderr, "Could not set GPGME home dir to %s\n", homedir);
219
fprintf(stderr, "Could not set GPGME home dir to %s\n", tempdir);
223
/* Create new GPGME "context" */
224
rc = gpgme_new(&(mc->ctx));
225
if (rc != GPG_ERR_NO_ERROR){
226
fprintf(stderr, "bad gpgme_new: %s: %s\n",
227
gpgme_strsource(rc), gpgme_strerror(rc));
231
if (not import_key(pubkey) or not import_key(seckey)){
239
* Decrypt OpenPGP data.
240
* Returns -1 on error
242
static ssize_t pgp_packet_decrypt (const mandos_context *mc,
243
const char *cryptotext,
246
gpgme_data_t dh_crypto, dh_plain;
249
size_t plaintext_capacity = 0;
250
ssize_t plaintext_length = 0;
253
fprintf(stderr, "Trying to decrypt OpenPGP data\n");
159
256
/* Create new GPGME data buffer from memory cryptotext */
177
/* Create new GPGME "context" */
178
rc = gpgme_new(&ctx);
179
if (rc != GPG_ERR_NO_ERROR){
180
fprintf(stderr, "bad gpgme_new: %s: %s\n",
181
gpgme_strsource(rc), gpgme_strerror(rc));
182
plaintext_length = -1;
186
274
/* Decrypt data from the cryptotext data buffer to the plaintext
188
rc = gpgme_op_decrypt(ctx, dh_crypto, dh_plain);
276
rc = gpgme_op_decrypt(mc->ctx, dh_crypto, dh_plain);
189
277
if (rc != GPG_ERR_NO_ERROR){
190
278
fprintf(stderr, "bad gpgme_op_decrypt: %s: %s\n",
191
279
gpgme_strsource(rc), gpgme_strerror(rc));
192
280
plaintext_length = -1;
282
gpgme_decrypt_result_t result;
283
result = gpgme_op_decrypt_result(mc->ctx);
285
fprintf(stderr, "gpgme_op_decrypt_result failed\n");
287
fprintf(stderr, "Unsupported algorithm: %s\n",
288
result->unsupported_algorithm);
289
fprintf(stderr, "Wrong key usage: %u\n",
290
result->wrong_key_usage);
291
if(result->file_name != NULL){
292
fprintf(stderr, "File name: %s\n", result->file_name);
294
gpgme_recipient_t recipient;
295
recipient = result->recipients;
297
while(recipient != NULL){
298
fprintf(stderr, "Public key algorithm: %s\n",
299
gpgme_pubkey_algo_name(recipient->pubkey_algo));
300
fprintf(stderr, "Key ID: %s\n", recipient->keyid);
301
fprintf(stderr, "Secret key available: %s\n",
302
recipient->status == GPG_ERR_NO_SECKEY
304
recipient = recipient->next;
193
309
goto decrypt_end;
197
313
fprintf(stderr, "Decryption of OpenPGP data succeeded\n");
201
gpgme_decrypt_result_t result;
202
result = gpgme_op_decrypt_result(ctx);
204
fprintf(stderr, "gpgme_op_decrypt_result failed\n");
206
fprintf(stderr, "Unsupported algorithm: %s\n",
207
result->unsupported_algorithm);
208
fprintf(stderr, "Wrong key usage: %d\n",
209
result->wrong_key_usage);
210
if(result->file_name != NULL){
211
fprintf(stderr, "File name: %s\n", result->file_name);
213
gpgme_recipient_t recipient;
214
recipient = result->recipients;
216
while(recipient != NULL){
217
fprintf(stderr, "Public key algorithm: %s\n",
218
gpgme_pubkey_algo_name(recipient->pubkey_algo));
219
fprintf(stderr, "Key ID: %s\n", recipient->keyid);
220
fprintf(stderr, "Secret key available: %s\n",
221
recipient->status == GPG_ERR_NO_SECKEY
223
recipient = recipient->next;
229
316
/* Seek back to the beginning of the GPGME plaintext data buffer */
230
317
if (gpgme_data_seek(dh_plain, (off_t) 0, SEEK_SET) == -1){
231
318
perror("pgpme_data_seek");
293
380
static int init_gnutls_global(mandos_context *mc,
294
const char *pubkeyfile,
295
const char *seckeyfile){
381
const char *pubkeyfilename,
382
const char *seckeyfilename){
299
386
fprintf(stderr, "Initializing GnuTLS\n");
302
if ((ret = gnutls_global_init ())
303
!= GNUTLS_E_SUCCESS) {
389
ret = gnutls_global_init();
390
if (ret != GNUTLS_E_SUCCESS) {
304
391
fprintf (stderr, "GnuTLS global_init: %s\n",
305
392
safer_gnutls_strerror(ret));
317
404
/* OpenPGP credentials */
318
if ((ret = gnutls_certificate_allocate_credentials (&mc->cred))
319
!= GNUTLS_E_SUCCESS) {
320
fprintf (stderr, "GnuTLS memory error: %s\n",
405
gnutls_certificate_allocate_credentials(&mc->cred);
406
if (ret != GNUTLS_E_SUCCESS){
407
fprintf (stderr, "GnuTLS memory error: %s\n", /* Spurious
321
409
safer_gnutls_strerror(ret));
322
410
gnutls_global_deinit ();
327
fprintf(stderr, "Attempting to use OpenPGP certificate %s"
328
" and keyfile %s as GnuTLS credentials\n", pubkeyfile,
415
fprintf(stderr, "Attempting to use OpenPGP public key %s and"
416
" secret key %s as GnuTLS credentials\n", pubkeyfilename,
332
420
ret = gnutls_certificate_set_openpgp_key_file
333
(mc->cred, pubkeyfile, seckeyfile, GNUTLS_OPENPGP_FMT_BASE64);
421
(mc->cred, pubkeyfilename, seckeyfilename,
422
GNUTLS_OPENPGP_FMT_BASE64);
334
423
if (ret != GNUTLS_E_SUCCESS) {
336
425
"Error[%d] while reading the OpenPGP key pair ('%s',"
337
" '%s')\n", ret, pubkeyfile, seckeyfile);
338
fprintf(stdout, "The GnuTLS error is: %s\n",
426
" '%s')\n", ret, pubkeyfilename, seckeyfilename);
427
fprintf(stderr, "The GnuTLS error is: %s\n",
339
428
safer_gnutls_strerror(ret));
463
551
fprintf(stderr, "Bad address: %s\n", ip);
466
to.in6.sin6_port = htons(port); /* Spurious warning */
554
to.in6.sin6_port = htons(port); /* Spurious warning */
468
556
to.in6.sin6_scope_id = (uint32_t)if_index;
471
fprintf(stderr, "Connection to: %s, port %d\n", ip, port);
559
fprintf(stderr, "Connection to: %s, port %" PRIu16 "\n", ip,
472
561
char addrstr[INET6_ADDRSTRLEN] = "";
473
562
if(inet_ntop(to.in6.sin6_family, &(to.in6.sin6_addr), addrstr,
474
563
sizeof(addrstr)) == NULL){
649
746
char ip[AVAHI_ADDRESS_STR_MAX];
650
747
avahi_address_snprint(ip, sizeof(ip), address);
652
fprintf(stderr, "Mandos server \"%s\" found on %s (%s, %d) on"
653
" port %d\n", name, host_name, ip, interface, port);
749
fprintf(stderr, "Mandos server \"%s\" found on %s (%s, %"
750
PRIu16 ") on port %d\n", name, host_name, ip,
655
753
int ret = start_mandos_communication(ip, port, interface, mc);
755
avahi_simple_poll_quit(mc->simple_poll);
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
813
int main(int argc, char *argv[]){
737
814
AvahiSServiceBrowser *sb = NULL;
746
823
char *connect_to = NULL;
824
char tempdir[] = "/tmp/mandosXXXXXX";
747
825
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
748
const char *pubkeyfile = "pubkey.txt";
749
const char *seckeyfile = "seckey.txt";
826
const char *seckey = PATHDIR "/" SECKEY;
827
const char *pubkey = PATHDIR "/" PUBKEY;
750
829
mandos_context mc = { .simple_poll = NULL, .server = NULL,
751
.dh_bits = 1024, .priority = "SECURE256"};
830
.dh_bits = 1024, .priority = "SECURE256"
831
":!CTYPE-X.509:+CTYPE-OPENPGP" };
752
832
bool gnutls_initalized = false;
833
bool pgpme_initalized = false;
755
836
struct argp_option options[] = {
756
837
{ .name = "debug", .key = 128,
757
838
.doc = "Debug mode", .group = 3 },
758
839
{ .name = "connect", .key = 'c',
760
.doc = "Connect directly to a sepcified mandos server",
840
.arg = "ADDRESS:PORT",
841
.doc = "Connect directly to a specific Mandos server",
762
843
{ .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",
845
.doc = "Interface that will be used to search for Mandos"
770
848
{ .name = "seckey", .key = 's',
772
.doc = "Secret openpgp key for gnutls authentication",
850
.doc = "OpenPGP secret key file base name",
774
852
{ .name = "pubkey", .key = 'p',
776
.doc = "Public openpgp key for gnutls authentication",
854
.doc = "OpenPGP public key file base name",
778
856
{ .name = "dh-bits", .key = 129,
780
.doc = "dh-bits to use in gnutls communication",
858
.doc = "Bit length of the prime number used in the"
859
" Diffie-Hellman key exchange",
782
861
{ .name = "priority", .key = 130,
784
.doc = "GNUTLS priority", .group = 1 },
863
.doc = "GnuTLS priority string for the TLS handshake",
789
868
error_t parse_opt (int key, char *arg,
790
869
struct argp_state *state) {
791
870
/* Get the INPUT argument from `argp_parse', which we know is
792
871
a pointer to our plugin list pointer. */
873
case 128: /* --debug */
876
case 'c': /* --connect */
798
877
connect_to = arg;
879
case 'i': /* --interface */
882
case 's': /* --seckey */
885
case 'p': /* --pubkey */
888
case 129: /* --dh-bits */
814
890
mc.dh_bits = (unsigned int) strtol(arg, NULL, 10);
817
893
exit(EXIT_FAILURE);
896
case 130: /* --priority */
821
897
mc.priority = arg;
823
899
case ARGP_KEY_ARG:
824
900
argp_usage (state);
829
904
return ARGP_ERR_UNKNOWN;
834
909
struct argp argp = { .options = options, .parser = parse_opt,
836
911
.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;
912
" passwords from a Mandos server" };
913
ret = argp_parse (&argp, argc, argv, 0, 0, NULL);
914
if (ret == ARGP_ERR_UNKNOWN){
915
fprintf(stderr, "Unknown error while parsing arguments\n");
916
exitcode = EXIT_FAILURE;
921
/* If the interface is down, bring it up */
923
sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
926
exitcode = EXIT_FAILURE;
929
strcpy(network.ifr_name, interface);
930
ret = ioctl(sd, SIOCGIFFLAGS, &network);
932
perror("ioctl SIOCGIFFLAGS");
933
exitcode = EXIT_FAILURE;
936
if((network.ifr_flags & IFF_UP) == 0){
937
network.ifr_flags |= IFF_UP;
938
ret = ioctl(sd, SIOCSIFFLAGS, &network);
940
perror("ioctl SIOCSIFFLAGS");
941
exitcode = EXIT_FAILURE;
945
ret = TEMP_FAILURE_RETRY(close(sd));
865
954
ret = setuid(uid);
867
956
perror("setuid");
872
961
perror("setgid");
964
ret = init_gnutls_global(&mc, pubkey, seckey);
966
fprintf(stderr, "init_gnutls_global failed\n");
967
exitcode = EXIT_FAILURE;
970
gnutls_initalized = true;
973
if(mkdtemp(tempdir) == NULL){
979
if(not init_gpgme(&mc, pubkey, seckey, tempdir)){
980
fprintf(stderr, "pgpme_initalized failed\n");
981
exitcode = EXIT_FAILURE;
984
pgpme_initalized = true;
875
987
if_index = (AvahiIfIndex) if_nametoindex(interface);
876
988
if(if_index == 0){
877
989
fprintf(stderr, "No such interface: \"%s\"\n", interface);
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;
936
1021
avahi_set_log_function(empty_log);
1007
1092
if (mc.server != NULL)
1008
1093
avahi_server_free(mc.server);
1010
1095
if (mc.simple_poll != NULL)
1011
1096
avahi_simple_poll_free(mc.simple_poll);
1015
1098
if (gnutls_initalized){
1016
gnutls_certificate_free_credentials (mc.cred);
1099
gnutls_certificate_free_credentials(mc.cred);
1017
1100
gnutls_global_deinit ();
1103
if(pgpme_initalized){
1104
gpgme_release(mc.ctx);
1107
/* Removes the temp directory used by GPGME */
1108
if(tempdir[0] != '\0'){
1110
struct dirent *direntry;
1111
d = opendir(tempdir);
1116
direntry = readdir(d);
1117
if(direntry == NULL){
1120
if (direntry->d_type == DT_REG){
1121
char *fullname = NULL;
1122
ret = asprintf(&fullname, "%s/%s", tempdir,
1128
ret = unlink(fullname);
1130
fprintf(stderr, "unlink(\"%s\"): %s",
1131
fullname, strerror(errno));
1137
ret = rmdir(tempdir);
1020
1143
return exitcode;