32
33
#define _LARGEFILE_SOURCE
33
34
#define _FILE_OFFSET_BITS 64
35
#define _GNU_SOURCE /* TEMP_FAILURE_RETRY() */
36
#define _GNU_SOURCE /* TEMP_FAILURE_RETRY(), asprintf() */
37
#include <stdio.h> /* fprintf(), stderr, fwrite(), stdout,
38
#include <stdio.h> /* fprintf(), stderr, fwrite(),
39
40
#include <stdint.h> /* uint16_t, uint32_t */
40
41
#include <stddef.h> /* NULL, size_t, ssize_t */
41
42
#include <stdlib.h> /* free(), EXIT_SUCCESS, EXIT_FAILURE,
43
44
#include <stdbool.h> /* bool, true */
44
45
#include <string.h> /* memset(), strcmp(), strlen(),
45
strerror(), memcpy(), strcpy() */
46
strerror(), asprintf(), strcpy() */
46
47
#include <sys/ioctl.h> /* ioctl */
47
#include <net/if.h> /* ifreq, SIOCGIFFLAGS, SIOCSIFFLAGS,
49
48
#include <sys/types.h> /* socket(), inet_pton(), sockaddr,
50
49
sockaddr_in6, PF_INET6,
51
50
SOCK_STREAM, INET6_ADDRSTRLEN,
51
uid_t, gid_t, open(), opendir(), DIR */
52
#include <sys/stat.h> /* open() */
53
53
#include <sys/socket.h> /* socket(), struct sockaddr_in6,
54
54
struct in6_addr, inet_pton(),
56
#include <fcntl.h> /* open() */
57
#include <dirent.h> /* opendir(), struct dirent, readdir() */
58
#include <inttypes.h> /* PRIu16 */
56
59
#include <assert.h> /* assert() */
57
60
#include <errno.h> /* perror(), errno */
58
61
#include <time.h> /* time() */
59
62
#include <net/if.h> /* ioctl, ifreq, SIOCGIFFLAGS, IFF_UP,
60
63
SIOCSIFFLAGS, if_indextoname(),
61
64
if_nametoindex(), IF_NAMESIZE */
65
#include <netinet/in.h>
62
66
#include <unistd.h> /* close(), SEEK_SET, off_t, write(),
63
67
getuid(), getgid(), setuid(),
65
#include <netinet/in.h>
66
69
#include <arpa/inet.h> /* inet_pton(), htons */
67
70
#include <iso646.h> /* not, and */
68
71
#include <argp.h> /* struct argp_option, error_t, struct
90
94
GNUTLS_OPENPGP_FMT_BASE64 */
93
#include <gpgme.h> /* All GPGME types, constants and functions
97
#include <gpgme.h> /* All GPGME types, constants and
95
100
GPGME_PROTOCOL_OpenPGP,
98
103
#define BUFFER_SIZE 256
105
#define PATHDIR "/conf/conf.d/mandos"
106
#define SECKEY "seckey.txt"
107
#define PUBKEY "pubkey.txt"
100
109
bool debug = false;
101
static const char *keydir = "/conf/conf.d/mandos";
102
110
static const char mandos_protocol_version[] = "1";
103
const char *argp_program_version = "mandosclient 1.0";
111
const char *argp_program_version = "mandos-client " VERSION;
104
112
const char *argp_program_bug_address = "<mandos@fukt.bsnet.se>";
106
114
/* Used for passing in values through the Avahi callback functions */
134
* Decrypt OpenPGP data using keyrings in HOMEDIR.
135
* Returns -1 on error
137
static ssize_t pgp_packet_decrypt (const char *cryptotext,
140
const char *homedir){
141
gpgme_data_t dh_crypto, dh_plain;
145
static bool init_gpgme(mandos_context *mc, const char *seckey,
146
const char *pubkey, const char *tempdir){
143
148
gpgme_error_t rc;
145
size_t plaintext_capacity = 0;
146
ssize_t plaintext_length = 0;
147
149
gpgme_engine_info_t engine_info;
153
* Helper function to insert pub and seckey to the enigne keyring.
155
bool import_key(const char *filename){
157
gpgme_data_t pgp_data;
159
fd = TEMP_FAILURE_RETRY(open(filename, O_RDONLY));
165
rc = gpgme_data_new_from_fd(&pgp_data, fd);
166
if (rc != GPG_ERR_NO_ERROR){
167
fprintf(stderr, "bad gpgme_data_new_from_fd: %s: %s\n",
168
gpgme_strsource(rc), gpgme_strerror(rc));
172
rc = gpgme_op_import(mc->ctx, pgp_data);
173
if (rc != GPG_ERR_NO_ERROR){
174
fprintf(stderr, "bad gpgme_op_import: %s: %s\n",
175
gpgme_strsource(rc), gpgme_strerror(rc));
179
ret = TEMP_FAILURE_RETRY(close(fd));
183
gpgme_data_release(pgp_data);
150
fprintf(stderr, "Trying to decrypt OpenPGP data\n");
188
fprintf(stderr, "Initialize gpgme\n");
156
194
if (rc != GPG_ERR_NO_ERROR){
157
195
fprintf(stderr, "bad gpgme_engine_check_version: %s: %s\n",
158
196
gpgme_strsource(rc), gpgme_strerror(rc));
162
/* Set GPGME home directory for the OpenPGP engine only */
200
/* Set GPGME home directory for the OpenPGP engine only */
163
201
rc = gpgme_get_engine_info (&engine_info);
164
202
if (rc != GPG_ERR_NO_ERROR){
165
203
fprintf(stderr, "bad gpgme_get_engine_info: %s: %s\n",
166
204
gpgme_strsource(rc), gpgme_strerror(rc));
169
207
while(engine_info != NULL){
170
208
if(engine_info->protocol == GPGME_PROTOCOL_OpenPGP){
171
209
gpgme_set_engine_info(GPGME_PROTOCOL_OpenPGP,
172
engine_info->file_name, homedir);
210
engine_info->file_name, tempdir);
175
213
engine_info = engine_info->next;
177
215
if(engine_info == NULL){
178
fprintf(stderr, "Could not set GPGME home dir to %s\n", homedir);
216
fprintf(stderr, "Could not set GPGME home dir to %s\n", tempdir);
220
/* Create new GPGME "context" */
221
rc = gpgme_new(&(mc->ctx));
222
if (rc != GPG_ERR_NO_ERROR){
223
fprintf(stderr, "bad gpgme_new: %s: %s\n",
224
gpgme_strsource(rc), gpgme_strerror(rc));
228
if (not import_key(pubkey) or not import_key(seckey)){
236
* Decrypt OpenPGP data.
237
* Returns -1 on error
239
static ssize_t pgp_packet_decrypt (const mandos_context *mc,
240
const char *cryptotext,
243
gpgme_data_t dh_crypto, dh_plain;
246
size_t plaintext_capacity = 0;
247
ssize_t plaintext_length = 0;
250
fprintf(stderr, "Trying to decrypt OpenPGP data\n");
182
253
/* Create new GPGME data buffer from memory cryptotext */
200
/* Create new GPGME "context" */
201
rc = gpgme_new(&ctx);
202
if (rc != GPG_ERR_NO_ERROR){
203
fprintf(stderr, "bad gpgme_new: %s: %s\n",
204
gpgme_strsource(rc), gpgme_strerror(rc));
205
plaintext_length = -1;
209
271
/* Decrypt data from the cryptotext data buffer to the plaintext
211
rc = gpgme_op_decrypt(ctx, dh_crypto, dh_plain);
273
rc = gpgme_op_decrypt(mc->ctx, dh_crypto, dh_plain);
212
274
if (rc != GPG_ERR_NO_ERROR){
213
275
fprintf(stderr, "bad gpgme_op_decrypt: %s: %s\n",
214
276
gpgme_strsource(rc), gpgme_strerror(rc));
215
277
plaintext_length = -1;
279
gpgme_decrypt_result_t result;
280
result = gpgme_op_decrypt_result(mc->ctx);
282
fprintf(stderr, "gpgme_op_decrypt_result failed\n");
284
fprintf(stderr, "Unsupported algorithm: %s\n",
285
result->unsupported_algorithm);
286
fprintf(stderr, "Wrong key usage: %u\n",
287
result->wrong_key_usage);
288
if(result->file_name != NULL){
289
fprintf(stderr, "File name: %s\n", result->file_name);
291
gpgme_recipient_t recipient;
292
recipient = result->recipients;
294
while(recipient != NULL){
295
fprintf(stderr, "Public key algorithm: %s\n",
296
gpgme_pubkey_algo_name(recipient->pubkey_algo));
297
fprintf(stderr, "Key ID: %s\n", recipient->keyid);
298
fprintf(stderr, "Secret key available: %s\n",
299
recipient->status == GPG_ERR_NO_SECKEY
301
recipient = recipient->next;
216
306
goto decrypt_end;
220
310
fprintf(stderr, "Decryption of OpenPGP data succeeded\n");
224
gpgme_decrypt_result_t result;
225
result = gpgme_op_decrypt_result(ctx);
227
fprintf(stderr, "gpgme_op_decrypt_result failed\n");
229
fprintf(stderr, "Unsupported algorithm: %s\n",
230
result->unsupported_algorithm);
231
fprintf(stderr, "Wrong key usage: %d\n",
232
result->wrong_key_usage);
233
if(result->file_name != NULL){
234
fprintf(stderr, "File name: %s\n", result->file_name);
236
gpgme_recipient_t recipient;
237
recipient = result->recipients;
239
while(recipient != NULL){
240
fprintf(stderr, "Public key algorithm: %s\n",
241
gpgme_pubkey_algo_name(recipient->pubkey_algo));
242
fprintf(stderr, "Key ID: %s\n", recipient->keyid);
243
fprintf(stderr, "Secret key available: %s\n",
244
recipient->status == GPG_ERR_NO_SECKEY
246
recipient = recipient->next;
252
313
/* Seek back to the beginning of the GPGME plaintext data buffer */
253
314
if (gpgme_data_seek(dh_plain, (off_t) 0, SEEK_SET) == -1){
254
perror("pgpme_data_seek");
315
perror("gpgme_data_seek");
255
316
plaintext_length = -1;
256
317
goto decrypt_end;
340
401
/* OpenPGP credentials */
341
402
gnutls_certificate_allocate_credentials(&mc->cred);
342
403
if (ret != GNUTLS_E_SUCCESS){
343
fprintf (stderr, "GnuTLS memory error: %s\n",
404
fprintf (stderr, "GnuTLS memory error: %s\n", /* Spurious
344
406
safer_gnutls_strerror(ret));
345
407
gnutls_global_deinit ();
350
fprintf(stderr, "Attempting to use OpenPGP certificate %s"
351
" and keyfile %s as GnuTLS credentials\n", pubkeyfile,
412
fprintf(stderr, "Attempting to use OpenPGP public key %s and"
413
" secret key %s as GnuTLS credentials\n", pubkeyfilename,
355
417
ret = gnutls_certificate_set_openpgp_key_file
356
(mc->cred, pubkeyfile, seckeyfile, GNUTLS_OPENPGP_FMT_BASE64);
418
(mc->cred, pubkeyfilename, seckeyfilename,
419
GNUTLS_OPENPGP_FMT_BASE64);
357
420
if (ret != GNUTLS_E_SUCCESS) {
359
422
"Error[%d] while reading the OpenPGP key pair ('%s',"
360
" '%s')\n", ret, pubkeyfile, seckeyfile);
361
fprintf(stdout, "The GnuTLS error is: %s\n",
423
" '%s')\n", ret, pubkeyfilename, seckeyfilename);
424
fprintf(stderr, "The GnuTLS error is: %s\n",
362
425
safer_gnutls_strerror(ret));
486
549
fprintf(stderr, "Bad address: %s\n", ip);
489
to.in6.sin6_port = htons(port); /* Spurious warning */
552
to.in6.sin6_port = htons(port); /* Spurious warning */
491
554
to.in6.sin6_scope_id = (uint32_t)if_index;
494
fprintf(stderr, "Connection to: %s, port %d\n", ip, port);
557
fprintf(stderr, "Connection to: %s, port %" PRIu16 "\n", ip,
495
559
char addrstr[INET6_ADDRSTRLEN] = "";
496
560
if(inet_ntop(to.in6.sin6_family, &(to.in6.sin6_addr), addrstr,
497
561
sizeof(addrstr)) == NULL){
676
744
char ip[AVAHI_ADDRESS_STR_MAX];
677
745
avahi_address_snprint(ip, sizeof(ip), address);
679
fprintf(stderr, "Mandos server \"%s\" found on %s (%s, %d) on"
680
" port %d\n", name, host_name, ip, interface, port);
747
fprintf(stderr, "Mandos server \"%s\" found on %s (%s, %"
748
PRIu16 ") on port %d\n", name, host_name, ip,
682
751
int ret = start_mandos_communication(ip, port, interface, mc);
753
avahi_simple_poll_quit(mc->simple_poll);
742
/* Combines file name and path and returns the malloced new
743
string. some sane checks could/should be added */
744
static const char *combinepath(const char *first, const char *second){
745
size_t f_len = strlen(first);
746
size_t s_len = strlen(second);
747
char *tmp = malloc(f_len + s_len + 2);
752
memcpy(tmp, first, f_len); /* Spurious warning */
756
memcpy(tmp + f_len + 1, second, s_len); /* Spurious warning */
758
tmp[f_len + 1 + s_len] = '\0';
763
811
int main(int argc, char *argv[]){
764
812
AvahiSServiceBrowser *sb = NULL;
773
821
char *connect_to = NULL;
822
char tempdir[] = "/tmp/mandosXXXXXX";
774
823
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
775
const char *pubkeyfile = "pubkey.txt";
776
const char *seckeyfile = "seckey.txt";
824
const char *seckey = PATHDIR "/" SECKEY;
825
const char *pubkey = PATHDIR "/" PUBKEY;
777
827
mandos_context mc = { .simple_poll = NULL, .server = NULL,
778
.dh_bits = 1024, .priority = "SECURE256"};
828
.dh_bits = 1024, .priority = "SECURE256"
829
":!CTYPE-X.509:+CTYPE-OPENPGP" };
779
830
bool gnutls_initalized = false;
831
bool gpgme_initalized = false;
782
834
struct argp_option options[] = {
783
835
{ .name = "debug", .key = 128,
784
836
.doc = "Debug mode", .group = 3 },
785
837
{ .name = "connect", .key = 'c',
787
.doc = "Connect directly to a sepcified mandos server",
838
.arg = "ADDRESS:PORT",
839
.doc = "Connect directly to a specific Mandos server",
789
841
{ .name = "interface", .key = 'i',
791
.doc = "Interface that Avahi will conntect through",
793
{ .name = "keydir", .key = 'd',
795
.doc = "Directory where the openpgp keyring is",
843
.doc = "Interface that will be used to search for Mandos"
797
846
{ .name = "seckey", .key = 's',
799
.doc = "Secret openpgp key for gnutls authentication",
848
.doc = "OpenPGP secret key file base name",
801
850
{ .name = "pubkey", .key = 'p',
803
.doc = "Public openpgp key for gnutls authentication",
852
.doc = "OpenPGP public key file base name",
805
854
{ .name = "dh-bits", .key = 129,
807
.doc = "dh-bits to use in gnutls communication",
856
.doc = "Bit length of the prime number used in the"
857
" Diffie-Hellman key exchange",
809
859
{ .name = "priority", .key = 130,
811
.doc = "GNUTLS priority", .group = 1 },
861
.doc = "GnuTLS priority string for the TLS handshake",
816
866
error_t parse_opt (int key, char *arg,
817
867
struct argp_state *state) {
818
868
/* Get the INPUT argument from `argp_parse', which we know is
819
869
a pointer to our plugin list pointer. */
871
case 128: /* --debug */
874
case 'c': /* --connect */
825
875
connect_to = arg;
877
case 'i': /* --interface */
880
case 's': /* --seckey */
883
case 'p': /* --pubkey */
886
case 129: /* --dh-bits */
841
888
mc.dh_bits = (unsigned int) strtol(arg, NULL, 10);
844
891
exit(EXIT_FAILURE);
894
case 130: /* --priority */
848
895
mc.priority = arg;
850
897
case ARGP_KEY_ARG:
851
898
argp_usage (state);
856
902
return ARGP_ERR_UNKNOWN;
861
907
struct argp argp = { .options = options, .parser = parse_opt,
863
909
.doc = "Mandos client -- Get and decrypt"
864
" passwords from mandos server" };
910
" passwords from a Mandos server" };
865
911
ret = argp_parse (&argp, argc, argv, 0, 0, NULL);
866
912
if (ret == ARGP_ERR_UNKNOWN){
867
fprintf(stderr, "Unkown error while parsing arguments\n");
868
exitcode = EXIT_FAILURE;
873
pubkeyfile = combinepath(keydir, pubkeyfile);
874
if (pubkeyfile == NULL){
875
perror("combinepath");
876
exitcode = EXIT_FAILURE;
880
seckeyfile = combinepath(keydir, seckeyfile);
881
if (seckeyfile == NULL){
882
perror("combinepath");
886
ret = init_gnutls_global(&mc, pubkeyfile, seckeyfile);
888
fprintf(stderr, "init_gnutls_global\n");
891
gnutls_initalized = true;
913
fprintf(stderr, "Unknown error while parsing arguments\n");
914
exitcode = EXIT_FAILURE;
919
/* If the interface is down, bring it up */
921
sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
924
exitcode = EXIT_FAILURE;
927
strcpy(network.ifr_name, interface);
928
ret = ioctl(sd, SIOCGIFFLAGS, &network);
930
perror("ioctl SIOCGIFFLAGS");
931
exitcode = EXIT_FAILURE;
934
if((network.ifr_flags & IFF_UP) == 0){
935
network.ifr_flags |= IFF_UP;
936
ret = ioctl(sd, SIOCSIFFLAGS, &network);
938
perror("ioctl SIOCSIFFLAGS");
939
exitcode = EXIT_FAILURE;
943
ret = TEMP_FAILURE_RETRY(close(sd));
897
952
ret = setuid(uid);
899
954
perror("setuid");
904
959
perror("setgid");
962
ret = init_gnutls_global(&mc, pubkey, seckey);
964
fprintf(stderr, "init_gnutls_global failed\n");
965
exitcode = EXIT_FAILURE;
968
gnutls_initalized = true;
971
if(mkdtemp(tempdir) == NULL){
977
if(not init_gpgme(&mc, pubkey, seckey, tempdir)){
978
fprintf(stderr, "gpgme_initalized failed\n");
979
exitcode = EXIT_FAILURE;
982
gpgme_initalized = true;
907
985
if_index = (AvahiIfIndex) if_nametoindex(interface);
908
986
if(if_index == 0){
909
987
fprintf(stderr, "No such interface: \"%s\"\n", interface);
940
/* If the interface is down, bring it up */
942
sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
945
exitcode = EXIT_FAILURE;
948
strcpy(network.ifr_name, interface); /* Spurious warning */
949
ret = ioctl(sd, SIOCGIFFLAGS, &network);
951
perror("ioctl SIOCGIFFLAGS");
952
exitcode = EXIT_FAILURE;
955
if((network.ifr_flags & IFF_UP) == 0){
956
network.ifr_flags |= IFF_UP;
957
ret = ioctl(sd, SIOCSIFFLAGS, &network);
959
perror("ioctl SIOCSIFFLAGS");
960
exitcode = EXIT_FAILURE;
968
1019
avahi_set_log_function(empty_log);
988
1039
config.publish_addresses = 0;
989
1040
config.publish_workstation = 0;
990
1041
config.publish_domain = 0;
992
1043
/* Allocate a new server */
993
1044
mc.server = avahi_server_new(avahi_simple_poll_get
994
1045
(mc.simple_poll), &config, NULL,
997
1048
/* Free the Avahi configuration data */
998
1049
avahi_server_config_free(&config);
1039
1090
if (mc.server != NULL)
1040
1091
avahi_server_free(mc.server);
1042
1093
if (mc.simple_poll != NULL)
1043
1094
avahi_simple_poll_free(mc.simple_poll);
1047
1096
if (gnutls_initalized){
1048
1097
gnutls_certificate_free_credentials(mc.cred);
1049
1098
gnutls_global_deinit ();
1099
gnutls_dh_params_deinit(mc.dh_params);
1102
if(gpgme_initalized){
1103
gpgme_release(mc.ctx);
1106
/* Removes the temp directory used by GPGME */
1107
if(tempdir[0] != '\0'){
1109
struct dirent *direntry;
1110
d = opendir(tempdir);
1115
direntry = readdir(d);
1116
if(direntry == NULL){
1119
if (direntry->d_type == DT_REG){
1120
char *fullname = NULL;
1121
ret = asprintf(&fullname, "%s/%s", tempdir,
1127
ret = unlink(fullname);
1129
fprintf(stderr, "unlink(\"%s\"): %s",
1130
fullname, strerror(errno));
1137
ret = rmdir(tempdir);
1052
1143
return exitcode;