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
stdout, ferror(), sscanf(),
39
41
#include <stdint.h> /* uint16_t, uint32_t */
40
42
#include <stddef.h> /* NULL, size_t, ssize_t */
41
43
#include <stdlib.h> /* free(), EXIT_SUCCESS, EXIT_FAILURE,
43
45
#include <stdbool.h> /* bool, true */
44
46
#include <string.h> /* memset(), strcmp(), strlen(),
45
strerror(), memcpy(), strcpy() */
47
strerror(), asprintf(), strcpy() */
46
48
#include <sys/ioctl.h> /* ioctl */
47
49
#include <sys/types.h> /* socket(), inet_pton(), sockaddr,
48
50
sockaddr_in6, PF_INET6,
49
51
SOCK_STREAM, INET6_ADDRSTRLEN,
51
#include <inttypes.h> /* PRIu16 */
52
uid_t, gid_t, open(), opendir(),
54
#include <sys/stat.h> /* open() */
52
55
#include <sys/socket.h> /* socket(), struct sockaddr_in6,
53
56
struct in6_addr, inet_pton(),
58
#include <fcntl.h> /* open() */
59
#include <dirent.h> /* opendir(), struct dirent, readdir()
61
#include <inttypes.h> /* PRIu16, intmax_t, SCNdMAX */
55
62
#include <assert.h> /* assert() */
56
63
#include <errno.h> /* perror(), errno */
57
#include <time.h> /* time() */
64
#include <time.h> /* nanosleep(), time() */
58
65
#include <net/if.h> /* ioctl, ifreq, SIOCGIFFLAGS, IFF_UP,
59
66
SIOCSIFFLAGS, if_indextoname(),
60
67
if_nametoindex(), IF_NAMESIZE */
68
#include <netinet/in.h>
61
69
#include <unistd.h> /* close(), SEEK_SET, off_t, write(),
62
70
getuid(), getgid(), setuid(),
64
#include <netinet/in.h>
65
72
#include <arpa/inet.h> /* inet_pton(), htons */
66
#include <iso646.h> /* not, and */
73
#include <iso646.h> /* not, and, or */
67
74
#include <argp.h> /* struct argp_option, error_t, struct
68
75
argp_state, struct argp,
69
76
argp_parse(), ARGP_KEY_ARG,
70
77
ARGP_KEY_END, ARGP_ERR_UNKNOWN */
79
#include <sys/klog.h> /* klogctl() */
73
83
/* All Avahi types, constants and functions
133
* Decrypt OpenPGP data using keyrings in HOMEDIR.
134
* Returns -1 on error
136
static ssize_t pgp_packet_decrypt (const char *cryptotext,
139
const char *homedir){
140
gpgme_data_t dh_crypto, dh_plain;
152
static bool init_gpgme(mandos_context *mc, const char *seckey,
153
const char *pubkey, const char *tempdir){
142
155
gpgme_error_t rc;
144
size_t plaintext_capacity = 0;
145
ssize_t plaintext_length = 0;
146
156
gpgme_engine_info_t engine_info;
149
fprintf(stderr, "Trying to decrypt OpenPGP data\n");
160
* Helper function to insert pub and seckey to the engine keyring.
162
bool import_key(const char *filename){
164
gpgme_data_t pgp_data;
166
fd = (int)TEMP_FAILURE_RETRY(open(filename, O_RDONLY));
172
rc = gpgme_data_new_from_fd(&pgp_data, fd);
173
if(rc != GPG_ERR_NO_ERROR){
174
fprintf(stderr, "bad gpgme_data_new_from_fd: %s: %s\n",
175
gpgme_strsource(rc), gpgme_strerror(rc));
179
rc = gpgme_op_import(mc->ctx, pgp_data);
180
if(rc != GPG_ERR_NO_ERROR){
181
fprintf(stderr, "bad gpgme_op_import: %s: %s\n",
182
gpgme_strsource(rc), gpgme_strerror(rc));
186
ret = (int)TEMP_FAILURE_RETRY(close(fd));
190
gpgme_data_release(pgp_data);
195
fprintf(stderr, "Initialize gpgme\n");
153
199
gpgme_check_version(NULL);
154
200
rc = gpgme_engine_check_version(GPGME_PROTOCOL_OpenPGP);
155
if (rc != GPG_ERR_NO_ERROR){
201
if(rc != GPG_ERR_NO_ERROR){
156
202
fprintf(stderr, "bad gpgme_engine_check_version: %s: %s\n",
157
203
gpgme_strsource(rc), gpgme_strerror(rc));
161
/* Set GPGME home directory for the OpenPGP engine only */
162
rc = gpgme_get_engine_info (&engine_info);
163
if (rc != GPG_ERR_NO_ERROR){
207
/* Set GPGME home directory for the OpenPGP engine only */
208
rc = gpgme_get_engine_info(&engine_info);
209
if(rc != GPG_ERR_NO_ERROR){
164
210
fprintf(stderr, "bad gpgme_get_engine_info: %s: %s\n",
165
211
gpgme_strsource(rc), gpgme_strerror(rc));
168
214
while(engine_info != NULL){
169
215
if(engine_info->protocol == GPGME_PROTOCOL_OpenPGP){
170
216
gpgme_set_engine_info(GPGME_PROTOCOL_OpenPGP,
171
engine_info->file_name, homedir);
217
engine_info->file_name, tempdir);
174
220
engine_info = engine_info->next;
176
222
if(engine_info == NULL){
177
fprintf(stderr, "Could not set GPGME home dir to %s\n", homedir);
223
fprintf(stderr, "Could not set GPGME home dir to %s\n", tempdir);
227
/* Create new GPGME "context" */
228
rc = gpgme_new(&(mc->ctx));
229
if(rc != GPG_ERR_NO_ERROR){
230
fprintf(stderr, "bad gpgme_new: %s: %s\n",
231
gpgme_strsource(rc), gpgme_strerror(rc));
235
if(not import_key(pubkey) or not import_key(seckey)){
243
* Decrypt OpenPGP data.
244
* Returns -1 on error
246
static ssize_t pgp_packet_decrypt(const mandos_context *mc,
247
const char *cryptotext,
250
gpgme_data_t dh_crypto, dh_plain;
253
size_t plaintext_capacity = 0;
254
ssize_t plaintext_length = 0;
257
fprintf(stderr, "Trying to decrypt OpenPGP data\n");
181
260
/* Create new GPGME data buffer from memory cryptotext */
182
261
rc = gpgme_data_new_from_mem(&dh_crypto, cryptotext, crypto_size,
184
if (rc != GPG_ERR_NO_ERROR){
263
if(rc != GPG_ERR_NO_ERROR){
185
264
fprintf(stderr, "bad gpgme_data_new_from_mem: %s: %s\n",
186
265
gpgme_strsource(rc), gpgme_strerror(rc));
743
/* Combines file name and path and returns the malloced new
744
string. some sane checks could/should be added */
745
static const char *combinepath(const char *first, const char *second){
746
size_t f_len = strlen(first);
747
size_t s_len = strlen(second);
748
char *tmp = malloc(f_len + s_len + 2);
753
memcpy(tmp, first, f_len); /* Spurious warning */
757
memcpy(tmp + f_len + 1, second, s_len); /* Spurious warning */
759
tmp[f_len + 1 + s_len] = '\0';
764
824
int main(int argc, char *argv[]){
765
AvahiSServiceBrowser *sb = NULL;
768
int exitcode = EXIT_SUCCESS;
769
const char *interface = "eth0";
770
struct ifreq network;
774
char *connect_to = NULL;
775
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
776
const char *pubkeyfile = "pubkey.txt";
777
const char *seckeyfile = "seckey.txt";
778
mandos_context mc = { .simple_poll = NULL, .server = NULL,
779
.dh_bits = 1024, .priority = "SECURE256"};
780
bool gnutls_initalized = false;
783
struct argp_option options[] = {
784
{ .name = "debug", .key = 128,
785
.doc = "Debug mode", .group = 3 },
786
{ .name = "connect", .key = 'c',
788
.doc = "Connect directly to a sepcified mandos server",
790
{ .name = "interface", .key = 'i',
792
.doc = "Interface that Avahi will conntect through",
794
{ .name = "keydir", .key = 'd',
796
.doc = "Directory where the openpgp keyring is",
798
{ .name = "seckey", .key = 's',
800
.doc = "Secret openpgp key for gnutls authentication",
802
{ .name = "pubkey", .key = 'p',
804
.doc = "Public openpgp key for gnutls authentication",
806
{ .name = "dh-bits", .key = 129,
808
.doc = "dh-bits to use in gnutls communication",
810
{ .name = "priority", .key = 130,
812
.doc = "GNUTLS priority", .group = 1 },
817
error_t parse_opt (int key, char *arg,
818
struct argp_state *state) {
819
/* Get the INPUT argument from `argp_parse', which we know is
820
a pointer to our plugin list pointer. */
842
mc.dh_bits = (unsigned int) strtol(arg, NULL, 10);
856
return ARGP_ERR_UNKNOWN;
861
struct argp argp = { .options = options, .parser = parse_opt,
863
.doc = "Mandos client -- Get and decrypt"
864
" passwords from mandos server" };
865
ret = argp_parse (&argp, argc, argv, 0, 0, NULL);
866
if (ret == ARGP_ERR_UNKNOWN){
867
fprintf(stderr, "Unknown 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");
883
exitcode = EXIT_FAILURE;
887
ret = init_gnutls_global(&mc, pubkeyfile, seckeyfile);
889
fprintf(stderr, "init_gnutls_global failed\n");
890
exitcode = EXIT_FAILURE;
893
gnutls_initalized = true;
896
/* If the interface is down, bring it up */
898
sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
901
exitcode = EXIT_FAILURE;
904
strcpy(network.ifr_name, interface); /* Spurious warning */
825
AvahiSServiceBrowser *sb = NULL;
830
int exitcode = EXIT_SUCCESS;
831
const char *interface = "eth0";
832
struct ifreq network;
836
char *connect_to = NULL;
837
char tempdir[] = "/tmp/mandosXXXXXX";
838
bool tempdir_created = false;
839
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
840
const char *seckey = PATHDIR "/" SECKEY;
841
const char *pubkey = PATHDIR "/" PUBKEY;
843
mandos_context mc = { .simple_poll = NULL, .server = NULL,
844
.dh_bits = 1024, .priority = "SECURE256"
845
":!CTYPE-X.509:+CTYPE-OPENPGP" };
846
bool gnutls_initialized = false;
847
bool gpgme_initialized = false;
851
struct argp_option options[] = {
852
{ .name = "debug", .key = 128,
853
.doc = "Debug mode", .group = 3 },
854
{ .name = "connect", .key = 'c',
855
.arg = "ADDRESS:PORT",
856
.doc = "Connect directly to a specific Mandos server",
858
{ .name = "interface", .key = 'i',
860
.doc = "Interface that will be used to search for Mandos"
863
{ .name = "seckey", .key = 's',
865
.doc = "OpenPGP secret key file base name",
867
{ .name = "pubkey", .key = 'p',
869
.doc = "OpenPGP public key file base name",
871
{ .name = "dh-bits", .key = 129,
873
.doc = "Bit length of the prime number used in the"
874
" Diffie-Hellman key exchange",
876
{ .name = "priority", .key = 130,
878
.doc = "GnuTLS priority string for the TLS handshake",
880
{ .name = "delay", .key = 131,
882
.doc = "Maximum delay to wait for interface startup",
887
error_t parse_opt(int key, char *arg,
888
struct argp_state *state){
890
case 128: /* --debug */
893
case 'c': /* --connect */
896
case 'i': /* --interface */
899
case 's': /* --seckey */
902
case 'p': /* --pubkey */
905
case 129: /* --dh-bits */
906
ret = sscanf(arg, "%" SCNdMAX "%n", &tmpmax, &numchars);
907
if(ret < 1 or tmpmax != (typeof(mc.dh_bits))tmpmax
908
or arg[numchars] != '\0'){
909
fprintf(stderr, "Bad number of DH bits\n");
912
mc.dh_bits = (typeof(mc.dh_bits))tmpmax;
914
case 130: /* --priority */
917
case 131: /* --delay */
918
ret = sscanf(arg, "%lf%n", &delay, &numchars);
919
if(ret < 1 or arg[numchars] != '\0'){
920
fprintf(stderr, "Bad delay\n");
929
return ARGP_ERR_UNKNOWN;
934
struct argp argp = { .options = options, .parser = parse_opt,
936
.doc = "Mandos client -- Get and decrypt"
937
" passwords from a Mandos server" };
938
ret = argp_parse(&argp, argc, argv, 0, 0, NULL);
939
if(ret == ARGP_ERR_UNKNOWN){
940
fprintf(stderr, "Unknown error while parsing arguments\n");
941
exitcode = EXIT_FAILURE;
946
/* If the interface is down, bring it up */
949
/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO
950
messages to mess up the prompt */
951
ret = klogctl(8, NULL, 5);
957
sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
960
exitcode = EXIT_FAILURE;
962
ret = klogctl(7, NULL, 0);
969
strcpy(network.ifr_name, interface);
970
ret = ioctl(sd, SIOCGIFFLAGS, &network);
972
perror("ioctl SIOCGIFFLAGS");
974
ret = klogctl(7, NULL, 0);
979
exitcode = EXIT_FAILURE;
982
if((network.ifr_flags & IFF_UP) == 0){
983
network.ifr_flags |= IFF_UP;
984
ret = ioctl(sd, SIOCSIFFLAGS, &network);
986
perror("ioctl SIOCSIFFLAGS");
987
exitcode = EXIT_FAILURE;
989
ret = klogctl(7, NULL, 0);
997
/* sleep checking until interface is running */
998
for(int i=0; i < delay * 4; i++){
905
999
ret = ioctl(sd, SIOCGIFFLAGS, &network);
907
1001
perror("ioctl SIOCGIFFLAGS");
908
exitcode = EXIT_FAILURE;
911
if((network.ifr_flags & IFF_UP) == 0){
912
network.ifr_flags |= IFF_UP;
913
ret = ioctl(sd, SIOCSIFFLAGS, &network);
915
perror("ioctl SIOCSIFFLAGS");
916
exitcode = EXIT_FAILURE;
936
if_index = (AvahiIfIndex) if_nametoindex(interface);
938
fprintf(stderr, "No such interface: \"%s\"\n", interface);
942
if(connect_to != NULL){
943
/* Connect directly, do not use Zeroconf */
944
/* (Mainly meant for debugging) */
945
char *address = strrchr(connect_to, ':');
947
fprintf(stderr, "No colon in address\n");
948
exitcode = EXIT_FAILURE;
952
uint16_t port = (uint16_t) strtol(address+1, NULL, 10);
954
perror("Bad port number");
955
exitcode = EXIT_FAILURE;
959
address = connect_to;
960
ret = start_mandos_communication(address, port, if_index, &mc);
962
exitcode = EXIT_FAILURE;
964
exitcode = EXIT_SUCCESS;
970
avahi_set_log_function(empty_log);
973
/* Initialize the pseudo-RNG for Avahi */
974
srand((unsigned int) time(NULL));
976
/* Allocate main Avahi loop object */
977
mc.simple_poll = avahi_simple_poll_new();
978
if (mc.simple_poll == NULL) {
979
fprintf(stderr, "Avahi: Failed to create simple poll"
981
exitcode = EXIT_FAILURE;
986
AvahiServerConfig config;
987
/* Do not publish any local Zeroconf records */
988
avahi_server_config_init(&config);
989
config.publish_hinfo = 0;
990
config.publish_addresses = 0;
991
config.publish_workstation = 0;
992
config.publish_domain = 0;
994
/* Allocate a new server */
995
mc.server = avahi_server_new(avahi_simple_poll_get
996
(mc.simple_poll), &config, NULL,
999
/* Free the Avahi configuration data */
1000
avahi_server_config_free(&config);
1003
/* Check if creating the Avahi server object succeeded */
1004
if (mc.server == NULL) {
1005
fprintf(stderr, "Failed to create Avahi server: %s\n",
1006
avahi_strerror(error));
1007
exitcode = EXIT_FAILURE;
1011
/* Create the Avahi service browser */
1012
sb = avahi_s_service_browser_new(mc.server, if_index,
1014
"_mandos._tcp", NULL, 0,
1015
browse_callback, &mc);
1017
fprintf(stderr, "Failed to create service browser: %s\n",
1018
avahi_strerror(avahi_server_errno(mc.server)));
1019
exitcode = EXIT_FAILURE;
1023
/* Run the main loop */
1026
fprintf(stderr, "Starting Avahi loop search\n");
1029
avahi_simple_poll_loop(mc.simple_poll);
1002
} else if(network.ifr_flags & IFF_RUNNING){
1005
struct timespec sleeptime = { .tv_nsec = 250000000 };
1006
ret = nanosleep(&sleeptime, NULL);
1007
if(ret == -1 and errno != EINTR){
1008
perror("nanosleep");
1011
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1016
/* Restores kernel loglevel to default */
1017
ret = klogctl(7, NULL, 0);
1037
ret = init_gnutls_global(&mc, pubkey, seckey);
1039
fprintf(stderr, "init_gnutls_global failed\n");
1040
exitcode = EXIT_FAILURE;
1043
gnutls_initialized = true;
1046
if(mkdtemp(tempdir) == NULL){
1050
tempdir_created = true;
1052
if(not init_gpgme(&mc, pubkey, seckey, tempdir)){
1053
fprintf(stderr, "init_gpgme failed\n");
1054
exitcode = EXIT_FAILURE;
1057
gpgme_initialized = true;
1060
if_index = (AvahiIfIndex) if_nametoindex(interface);
1062
fprintf(stderr, "No such interface: \"%s\"\n", interface);
1063
exitcode = EXIT_FAILURE;
1067
if(connect_to != NULL){
1068
/* Connect directly, do not use Zeroconf */
1069
/* (Mainly meant for debugging) */
1070
char *address = strrchr(connect_to, ':');
1071
if(address == NULL){
1072
fprintf(stderr, "No colon in address\n");
1073
exitcode = EXIT_FAILURE;
1077
ret = sscanf(address+1, "%" SCNdMAX "%n", &tmpmax, &numchars);
1078
if(ret < 1 or tmpmax != (uint16_t)tmpmax
1079
or address[numchars+1] != '\0'){
1080
fprintf(stderr, "Bad port number\n");
1081
exitcode = EXIT_FAILURE;
1084
port = (uint16_t)tmpmax;
1086
address = connect_to;
1087
ret = start_mandos_communication(address, port, if_index, &mc);
1089
exitcode = EXIT_FAILURE;
1091
exitcode = EXIT_SUCCESS;
1097
avahi_set_log_function(empty_log);
1100
/* Initialize the pseudo-RNG for Avahi */
1101
srand((unsigned int) time(NULL));
1103
/* Allocate main Avahi loop object */
1104
mc.simple_poll = avahi_simple_poll_new();
1105
if(mc.simple_poll == NULL){
1106
fprintf(stderr, "Avahi: Failed to create simple poll object.\n");
1107
exitcode = EXIT_FAILURE;
1112
AvahiServerConfig config;
1113
/* Do not publish any local Zeroconf records */
1114
avahi_server_config_init(&config);
1115
config.publish_hinfo = 0;
1116
config.publish_addresses = 0;
1117
config.publish_workstation = 0;
1118
config.publish_domain = 0;
1120
/* Allocate a new server */
1121
mc.server = avahi_server_new(avahi_simple_poll_get
1122
(mc.simple_poll), &config, NULL,
1125
/* Free the Avahi configuration data */
1126
avahi_server_config_free(&config);
1129
/* Check if creating the Avahi server object succeeded */
1130
if(mc.server == NULL){
1131
fprintf(stderr, "Failed to create Avahi server: %s\n",
1132
avahi_strerror(error));
1133
exitcode = EXIT_FAILURE;
1137
/* Create the Avahi service browser */
1138
sb = avahi_s_service_browser_new(mc.server, if_index,
1139
AVAHI_PROTO_INET6, "_mandos._tcp",
1140
NULL, 0, browse_callback, &mc);
1142
fprintf(stderr, "Failed to create service browser: %s\n",
1143
avahi_strerror(avahi_server_errno(mc.server)));
1144
exitcode = EXIT_FAILURE;
1148
/* Run the main loop */
1151
fprintf(stderr, "Starting Avahi loop search\n");
1154
avahi_simple_poll_loop(mc.simple_poll);
1034
fprintf(stderr, "%s exiting\n", argv[0]);
1037
/* Cleanup things */
1039
avahi_s_service_browser_free(sb);
1041
if (mc.server != NULL)
1042
avahi_server_free(mc.server);
1044
if (mc.simple_poll != NULL)
1045
avahi_simple_poll_free(mc.simple_poll);
1049
if (gnutls_initalized){
1050
gnutls_certificate_free_credentials(mc.cred);
1051
gnutls_global_deinit ();
1159
fprintf(stderr, "%s exiting\n", argv[0]);
1162
/* Cleanup things */
1164
avahi_s_service_browser_free(sb);
1166
if(mc.server != NULL)
1167
avahi_server_free(mc.server);
1169
if(mc.simple_poll != NULL)
1170
avahi_simple_poll_free(mc.simple_poll);
1172
if(gnutls_initialized){
1173
gnutls_certificate_free_credentials(mc.cred);
1174
gnutls_global_deinit();
1175
gnutls_dh_params_deinit(mc.dh_params);
1178
if(gpgme_initialized){
1179
gpgme_release(mc.ctx);
1182
/* Removes the temp directory used by GPGME */
1183
if(tempdir_created){
1185
struct dirent *direntry;
1186
d = opendir(tempdir);
1188
if(errno != ENOENT){
1193
direntry = readdir(d);
1194
if(direntry == NULL){
1197
/* Skip "." and ".." */
1198
if(direntry->d_name[0] == '.'
1199
and (direntry->d_name[1] == '\0'
1200
or (direntry->d_name[1] == '.'
1201
and direntry->d_name[2] == '\0'))){
1204
char *fullname = NULL;
1205
ret = asprintf(&fullname, "%s/%s", tempdir,
1211
ret = remove(fullname);
1213
fprintf(stderr, "remove(\"%s\"): %s\n", fullname,
1220
ret = rmdir(tempdir);
1221
if(ret == -1 and errno != ENOENT){