33
32
#define _LARGEFILE_SOURCE
34
33
#define _FILE_OFFSET_BITS 64
36
#define _GNU_SOURCE /* TEMP_FAILURE_RETRY(), asprintf() */
35
#define _GNU_SOURCE /* TEMP_FAILURE_RETRY() */
38
#include <stdio.h> /* fprintf(), stderr, fwrite(),
40
#include <stdint.h> /* uint16_t, uint32_t */
41
#include <stddef.h> /* NULL, size_t, ssize_t */
42
#include <stdlib.h> /* free(), EXIT_SUCCESS, EXIT_FAILURE,
44
#include <stdbool.h> /* bool, true */
45
#include <string.h> /* memset(), strcmp(), strlen(),
46
strerror(), asprintf(), strcpy() */
47
#include <sys/ioctl.h> /* ioctl */
48
#include <sys/types.h> /* socket(), inet_pton(), sockaddr,
49
sockaddr_in6, PF_INET6,
50
SOCK_STREAM, INET6_ADDRSTRLEN,
51
uid_t, gid_t, open(), opendir(), DIR */
52
#include <sys/stat.h> /* open() */
53
#include <sys/socket.h> /* socket(), struct sockaddr_in6,
54
struct in6_addr, inet_pton(),
56
#include <fcntl.h> /* open() */
57
#include <dirent.h> /* opendir(), struct dirent, readdir() */
58
#include <inttypes.h> /* PRIu16 */
59
#include <assert.h> /* assert() */
60
#include <errno.h> /* perror(), errno */
61
#include <time.h> /* time() */
41
#include <net/if.h> /* if_nametoindex */
42
#include <sys/ioctl.h> /* ioctl, ifreq, SIOCGIFFLAGS, IFF_UP,
62
44
#include <net/if.h> /* ioctl, ifreq, SIOCGIFFLAGS, IFF_UP,
63
SIOCSIFFLAGS, if_indextoname(),
64
if_nametoindex(), IF_NAMESIZE */
65
#include <netinet/in.h>
66
#include <unistd.h> /* close(), SEEK_SET, off_t, write(),
67
getuid(), getgid(), setuid(),
69
#include <arpa/inet.h> /* inet_pton(), htons */
70
#include <iso646.h> /* not, and */
71
#include <argp.h> /* struct argp_option, error_t, struct
72
argp_state, struct argp,
73
argp_parse(), ARGP_KEY_ARG,
74
ARGP_KEY_END, ARGP_ERR_UNKNOWN */
77
/* All Avahi types, constants and functions
80
47
#include <avahi-core/core.h>
81
48
#include <avahi-core/lookup.h>
82
49
#include <avahi-core/log.h>
84
51
#include <avahi-common/malloc.h>
85
52
#include <avahi-common/error.h>
88
#include <gnutls/gnutls.h> /* All GnuTLS types, constants and
91
init_gnutls_session(),
93
#include <gnutls/openpgp.h> /* gnutls_certificate_set_openpgp_key_file(),
94
GNUTLS_OPENPGP_FMT_BASE64 */
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 */
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 */
97
#include <gpgme.h> /* All GPGME types, constants and
100
GPGME_PROTOCOL_OpenPGP,
70
#include <errno.h> /* perror() */
103
76
#define BUFFER_SIZE 256
105
#define PATHDIR "/conf/conf.d/mandos"
106
#define SECKEY "seckey.txt"
107
#define PUBKEY "pubkey.txt"
78
static const char *keydir = "/conf/conf.d/mandos";
79
static const char *pubkeyfile = "pubkey.txt";
80
static const char *seckeyfile = "seckey.txt";
109
82
bool debug = false;
110
static const char mandos_protocol_version[] = "1";
111
const char *argp_program_version = "mandos-client " VERSION;
112
const char *argp_program_bug_address = "<mandos@fukt.bsnet.se>";
114
/* Used for passing in values through the Avahi callback functions */
84
const char mandos_protocol_version[] = "1";
86
/* Used for passing in values through all the callback functions */
116
88
AvahiSimplePoll *simple_poll;
117
89
AvahiServer *server;
118
90
gnutls_certificate_credentials_t cred;
119
91
unsigned int dh_bits;
120
gnutls_dh_params_t dh_params;
121
92
const char *priority;
126
* Make room in "buffer" for at least BUFFER_SIZE additional bytes.
127
* "buffer_capacity" is how much is currently allocated,
128
* "buffer_length" is how much is already used.
130
95
size_t adjustbuffer(char **buffer, size_t buffer_length,
131
96
size_t buffer_capacity){
132
97
if (buffer_length + BUFFER_SIZE > buffer_capacity){
108
* Decrypt OpenPGP data using keyrings in HOMEDIR.
109
* Returns -1 on error
145
static bool init_gpgme(mandos_context *mc, const char *seckey,
146
const char *pubkey, const char *tempdir){
111
static ssize_t pgp_packet_decrypt (const char *cryptotext,
114
const char *homedir){
115
gpgme_data_t dh_crypto, dh_plain;
148
117
gpgme_error_t rc;
119
size_t plaintext_capacity = 0;
120
ssize_t plaintext_length = 0;
149
121
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 = (int)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 = (int)TEMP_FAILURE_RETRY(close(fd));
183
gpgme_data_release(pgp_data);
188
fprintf(stderr, "Initialize gpgme\n");
124
fprintf(stderr, "Trying to decrypt OpenPGP data\n");
194
130
if (rc != GPG_ERR_NO_ERROR){
195
131
fprintf(stderr, "bad gpgme_engine_check_version: %s: %s\n",
196
132
gpgme_strsource(rc), gpgme_strerror(rc));
200
/* Set GPGME home directory for the OpenPGP engine only */
136
/* Set GPGME home directory for the OpenPGP engine only */
201
137
rc = gpgme_get_engine_info (&engine_info);
202
138
if (rc != GPG_ERR_NO_ERROR){
203
139
fprintf(stderr, "bad gpgme_get_engine_info: %s: %s\n",
204
140
gpgme_strsource(rc), gpgme_strerror(rc));
207
143
while(engine_info != NULL){
208
144
if(engine_info->protocol == GPGME_PROTOCOL_OpenPGP){
209
145
gpgme_set_engine_info(GPGME_PROTOCOL_OpenPGP,
210
engine_info->file_name, tempdir);
146
engine_info->file_name, homedir);
213
149
engine_info = engine_info->next;
215
151
if(engine_info == NULL){
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");
152
fprintf(stderr, "Could not set GPGME home dir to %s\n", homedir);
253
156
/* Create new GPGME data buffer from memory cryptotext */
174
/* Create new GPGME "context" */
175
rc = gpgme_new(&ctx);
176
if (rc != GPG_ERR_NO_ERROR){
177
fprintf(stderr, "bad gpgme_new: %s: %s\n",
178
gpgme_strsource(rc), gpgme_strerror(rc));
179
plaintext_length = -1;
271
183
/* Decrypt data from the cryptotext data buffer to the plaintext
273
rc = gpgme_op_decrypt(mc->ctx, dh_crypto, dh_plain);
185
rc = gpgme_op_decrypt(ctx, dh_crypto, dh_plain);
274
186
if (rc != GPG_ERR_NO_ERROR){
275
187
fprintf(stderr, "bad gpgme_op_decrypt: %s: %s\n",
276
188
gpgme_strsource(rc), gpgme_strerror(rc));
277
189
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;
306
190
goto decrypt_end;
310
194
fprintf(stderr, "Decryption of OpenPGP data succeeded\n");
198
gpgme_decrypt_result_t result;
199
result = gpgme_op_decrypt_result(ctx);
201
fprintf(stderr, "gpgme_op_decrypt_result failed\n");
203
fprintf(stderr, "Unsupported algorithm: %s\n",
204
result->unsupported_algorithm);
205
fprintf(stderr, "Wrong key usage: %d\n",
206
result->wrong_key_usage);
207
if(result->file_name != NULL){
208
fprintf(stderr, "File name: %s\n", result->file_name);
210
gpgme_recipient_t recipient;
211
recipient = result->recipients;
213
while(recipient != NULL){
214
fprintf(stderr, "Public key algorithm: %s\n",
215
gpgme_pubkey_algo_name(recipient->pubkey_algo));
216
fprintf(stderr, "Key ID: %s\n", recipient->keyid);
217
fprintf(stderr, "Secret key available: %s\n",
218
recipient->status == GPG_ERR_NO_SECKEY
220
recipient = recipient->next;
313
226
/* Seek back to the beginning of the GPGME plaintext data buffer */
314
227
if (gpgme_data_seek(dh_plain, (off_t) 0, SEEK_SET) == -1){
315
perror("gpgme_data_seek");
228
perror("pgpme_data_seek");
316
229
plaintext_length = -1;
317
230
goto decrypt_end;
320
233
*plaintext = NULL;
322
plaintext_capacity = adjustbuffer(plaintext,
323
(size_t)plaintext_length,
235
plaintext_capacity = adjustbuffer(plaintext, (size_t)plaintext_length,
324
236
plaintext_capacity);
325
237
if (plaintext_capacity == 0){
326
238
perror("adjustbuffer");
401
312
/* OpenPGP credentials */
402
gnutls_certificate_allocate_credentials(&mc->cred);
403
if (ret != GNUTLS_E_SUCCESS){
404
fprintf (stderr, "GnuTLS memory error: %s\n", /* Spurious
313
if ((ret = gnutls_certificate_allocate_credentials (&mc->cred))
314
!= GNUTLS_E_SUCCESS) {
315
fprintf (stderr, "GnuTLS memory error: %s\n",
406
316
safer_gnutls_strerror(ret));
407
gnutls_global_deinit ();
412
fprintf(stderr, "Attempting to use OpenPGP public key %s and"
413
" secret key %s as GnuTLS credentials\n", pubkeyfilename,
321
fprintf(stderr, "Attempting to use OpenPGP certificate %s"
322
" and keyfile %s as GnuTLS credentials\n", pubkeyfile,
417
326
ret = gnutls_certificate_set_openpgp_key_file
418
(mc->cred, pubkeyfilename, seckeyfilename,
419
GNUTLS_OPENPGP_FMT_BASE64);
327
(mc->cred, pubkeyfile, seckeyfile, GNUTLS_OPENPGP_FMT_BASE64);
420
328
if (ret != GNUTLS_E_SUCCESS) {
422
330
"Error[%d] while reading the OpenPGP key pair ('%s',"
423
" '%s')\n", ret, pubkeyfilename, seckeyfilename);
424
fprintf(stderr, "The GnuTLS error is: %s\n",
331
" '%s')\n", ret, pubkeyfile, seckeyfile);
332
fprintf(stdout, "The GnuTLS error is: %s\n",
425
333
safer_gnutls_strerror(ret));
429
337
/* GnuTLS server initialization */
430
ret = gnutls_dh_params_init(&mc->dh_params);
338
ret = gnutls_dh_params_init(dh_params);
431
339
if (ret != GNUTLS_E_SUCCESS) {
432
340
fprintf (stderr, "Error in GnuTLS DH parameter initialization:"
433
341
" %s\n", safer_gnutls_strerror(ret));
436
ret = gnutls_dh_params_generate2(mc->dh_params, mc->dh_bits);
344
ret = gnutls_dh_params_generate2(*dh_params, mc->dh_bits);
437
345
if (ret != GNUTLS_E_SUCCESS) {
438
346
fprintf (stderr, "Error in GnuTLS prime generation: %s\n",
439
347
safer_gnutls_strerror(ret));
443
gnutls_certificate_set_dh_params(mc->cred, mc->dh_params);
449
gnutls_certificate_free_credentials(mc->cred);
450
gnutls_global_deinit();
451
gnutls_dh_params_deinit(mc->dh_params);
455
static int init_gnutls_session(mandos_context *mc,
456
gnutls_session_t *session){
351
gnutls_certificate_set_dh_params(mc->cred, *dh_params);
458
353
/* GnuTLS session creation */
459
354
ret = gnutls_init(session, GNUTLS_SERVER);
460
355
if (ret != GNUTLS_E_SUCCESS){
817
722
const char *interface = "eth0";
818
723
struct ifreq network;
822
725
char *connect_to = NULL;
823
char tempdir[] = "/tmp/mandosXXXXXX";
824
726
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
825
const char *seckey = PATHDIR "/" SECKEY;
826
const char *pubkey = PATHDIR "/" PUBKEY;
828
727
mandos_context mc = { .simple_poll = NULL, .server = NULL,
829
.dh_bits = 1024, .priority = "SECURE256"
830
":!CTYPE-X.509:+CTYPE-OPENPGP" };
831
bool gnutls_initalized = false;
832
bool gpgme_initalized = false;
728
.dh_bits = 1024, .priority = "SECURE256"};
835
struct argp_option options[] = {
836
{ .name = "debug", .key = 128,
837
.doc = "Debug mode", .group = 3 },
838
{ .name = "connect", .key = 'c',
839
.arg = "ADDRESS:PORT",
840
.doc = "Connect directly to a specific Mandos server",
842
{ .name = "interface", .key = 'i',
844
.doc = "Interface that will be used to search for Mandos"
847
{ .name = "seckey", .key = 's',
849
.doc = "OpenPGP secret key file base name",
851
{ .name = "pubkey", .key = 'p',
853
.doc = "OpenPGP public key file base name",
855
{ .name = "dh-bits", .key = 129,
857
.doc = "Bit length of the prime number used in the"
858
" Diffie-Hellman key exchange",
860
{ .name = "priority", .key = 130,
862
.doc = "GnuTLS priority string for the TLS handshake",
867
error_t parse_opt (int key, char *arg,
868
struct argp_state *state) {
869
/* Get the INPUT argument from `argp_parse', which we know is
870
a pointer to our plugin list pointer. */
872
case 128: /* --debug */
875
case 'c': /* --connect */
878
case 'i': /* --interface */
881
case 's': /* --seckey */
884
case 'p': /* --pubkey */
887
case 129: /* --dh-bits */
731
/* Temporary int to get the address of for getopt_long */
732
int debug_int = debug ? 1 : 0;
734
struct option long_options[] = {
735
{"debug", no_argument, &debug_int, 1},
736
{"connect", required_argument, NULL, 'c'},
737
{"interface", required_argument, NULL, 'i'},
738
{"keydir", required_argument, NULL, 'd'},
739
{"seckey", required_argument, NULL, 's'},
740
{"pubkey", required_argument, NULL, 'p'},
741
{"dh-bits", required_argument, NULL, 'D'},
742
{"priority", required_argument, NULL, 'P'},
745
int option_index = 0;
746
ret = getopt_long (argc, argv, "i:", long_options,
889
mc.dh_bits = (unsigned int) strtol(arg, NULL, 10);
773
mc.dh_bits = (unsigned int) strtol(optarg, NULL, 10);
891
775
perror("strtol");
892
776
exit(EXIT_FAILURE);
895
case 130: /* --priority */
780
mc.priority = optarg;
903
return ARGP_ERR_UNKNOWN;
908
struct argp argp = { .options = options, .parser = parse_opt,
910
.doc = "Mandos client -- Get and decrypt"
911
" passwords from a Mandos server" };
912
ret = argp_parse (&argp, argc, argv, 0, 0, NULL);
913
if (ret == ARGP_ERR_UNKNOWN){
914
fprintf(stderr, "Unknown error while parsing arguments\n");
915
exitcode = EXIT_FAILURE;
920
/* If the interface is down, bring it up */
922
sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
925
exitcode = EXIT_FAILURE;
928
strcpy(network.ifr_name, interface);
929
ret = ioctl(sd, SIOCGIFFLAGS, &network);
931
perror("ioctl SIOCGIFFLAGS");
932
exitcode = EXIT_FAILURE;
935
if((network.ifr_flags & IFF_UP) == 0){
936
network.ifr_flags |= IFF_UP;
937
ret = ioctl(sd, SIOCSIFFLAGS, &network);
939
perror("ioctl SIOCSIFFLAGS");
940
exitcode = EXIT_FAILURE;
944
ret = (int)TEMP_FAILURE_RETRY(close(sd));
963
ret = init_gnutls_global(&mc, pubkey, seckey);
965
fprintf(stderr, "init_gnutls_global failed\n");
966
exitcode = EXIT_FAILURE;
969
gnutls_initalized = true;
972
if(mkdtemp(tempdir) == NULL){
978
if(not init_gpgme(&mc, pubkey, seckey, tempdir)){
979
fprintf(stderr, "gpgme_initalized failed\n");
980
exitcode = EXIT_FAILURE;
983
gpgme_initalized = true;
784
/* getopt_long() has already printed a message about the
785
unrcognized option, so just exit. */
789
/* Set the global debug flag from the temporary int */
790
debug = debug_int ? true : false;
793
pubkeyfile = combinepath(keydir, pubkeyfile);
794
if (pubkeyfile == NULL){
795
perror("combinepath");
796
exitcode = EXIT_FAILURE;
800
seckeyfile = combinepath(keydir, seckeyfile);
801
if (seckeyfile == NULL){
802
perror("combinepath");
986
806
if_index = (AvahiIfIndex) if_nametoindex(interface);
995
815
char *address = strrchr(connect_to, ':');
996
816
if(address == NULL){
997
817
fprintf(stderr, "No colon in address\n");
998
exitcode = EXIT_FAILURE;
1002
821
uint16_t port = (uint16_t) strtol(address+1, NULL, 10);
1004
823
perror("Bad port number");
1005
exitcode = EXIT_FAILURE;
1008
826
*address = '\0';
1009
827
address = connect_to;
1010
828
ret = start_mandos_communication(address, port, if_index, &mc);
1012
exitcode = EXIT_FAILURE;
1014
exitcode = EXIT_SUCCESS;
836
/* If the interface is down, bring it up */
838
sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
841
exitcode = EXIT_FAILURE;
844
strcpy(network.ifr_name, interface); /* Spurious warning */
845
ret = ioctl(sd, SIOCGIFFLAGS, &network);
847
perror("ioctl SIOCGIFFLAGS");
848
exitcode = EXIT_FAILURE;
851
if((network.ifr_flags & IFF_UP) == 0){
852
network.ifr_flags |= IFF_UP;
853
ret = ioctl(sd, SIOCSIFFLAGS, &network);
855
perror("ioctl SIOCSIFFLAGS");
856
exitcode = EXIT_FAILURE;