36
35
#define _GNU_SOURCE /* TEMP_FAILURE_RETRY(), asprintf() */
38
37
#include <stdio.h> /* fprintf(), stderr, fwrite(),
39
stdout, ferror(), sscanf */
40
39
#include <stdint.h> /* uint16_t, uint32_t */
41
40
#include <stddef.h> /* NULL, size_t, ssize_t */
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41
#include <stdlib.h> /* free(), EXIT_SUCCESS, EXIT_FAILURE,
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#include <sys/types.h> /* socket(), inet_pton(), sockaddr,
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sockaddr_in6, PF_INET6,
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SOCK_STREAM, INET6_ADDRSTRLEN,
51
uid_t, gid_t, open(), opendir(), DIR */
52
#include <sys/stat.h> /* open() */
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#include <inttypes.h> /* PRIu16 */
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#include <sys/socket.h> /* socket(), struct sockaddr_in6,
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struct in6_addr, inet_pton(),
56
#include <fcntl.h> /* open() */
57
#include <dirent.h> /* opendir(), struct dirent, readdir() */
58
#include <inttypes.h> /* PRIu16, SCNu16 */
59
55
#include <assert.h> /* assert() */
60
56
#include <errno.h> /* perror(), errno */
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#include <time.h> /* time() */
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#include <net/if.h> /* ioctl, ifreq, SIOCGIFFLAGS, IFF_UP,
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SIOCSIFFLAGS, if_indextoname(),
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if_nametoindex(), IF_NAMESIZE */
65
#include <netinet/in.h>
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#include <unistd.h> /* close(), SEEK_SET, off_t, write(),
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62
getuid(), getgid(), setuid(),
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#include <netinet/in.h>
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65
#include <arpa/inet.h> /* inet_pton(), htons */
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#include <iso646.h> /* not, and, or */
66
#include <iso646.h> /* not, and */
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67
#include <argp.h> /* struct argp_option, error_t, struct
72
68
argp_state, struct argp,
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69
argp_parse(), ARGP_KEY_ARG,
135
* Decrypt OpenPGP data using keyrings in HOMEDIR.
136
* Returns -1 on error
145
static bool init_gpgme(mandos_context *mc, const char *seckey,
146
const char *pubkey, const char *tempdir){
138
static ssize_t pgp_packet_decrypt (const char *cryptotext,
141
const char *homedir){
142
gpgme_data_t dh_crypto, dh_plain;
148
144
gpgme_error_t rc;
146
size_t plaintext_capacity = 0;
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ssize_t plaintext_length = 0;
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148
gpgme_engine_info_t engine_info;
153
* Helper function to insert pub and seckey to the enigne keyring.
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bool import_key(const char *filename){
157
gpgme_data_t pgp_data;
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fd = (int)TEMP_FAILURE_RETRY(open(filename, O_RDONLY));
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rc = gpgme_data_new_from_fd(&pgp_data, fd);
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if (rc != GPG_ERR_NO_ERROR){
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fprintf(stderr, "bad gpgme_data_new_from_fd: %s: %s\n",
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gpgme_strsource(rc), gpgme_strerror(rc));
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rc = gpgme_op_import(mc->ctx, pgp_data);
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if (rc != GPG_ERR_NO_ERROR){
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fprintf(stderr, "bad gpgme_op_import: %s: %s\n",
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gpgme_strsource(rc), gpgme_strerror(rc));
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ret = (int)TEMP_FAILURE_RETRY(close(fd));
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gpgme_data_release(pgp_data);
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fprintf(stderr, "Initialize gpgme\n");
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fprintf(stderr, "Trying to decrypt OpenPGP data\n");
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157
if (rc != GPG_ERR_NO_ERROR){
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158
fprintf(stderr, "bad gpgme_engine_check_version: %s: %s\n",
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159
gpgme_strsource(rc), gpgme_strerror(rc));
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/* Set GPGME home directory for the OpenPGP engine only */
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/* Set GPGME home directory for the OpenPGP engine only */
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rc = gpgme_get_engine_info (&engine_info);
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if (rc != GPG_ERR_NO_ERROR){
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166
fprintf(stderr, "bad gpgme_get_engine_info: %s: %s\n",
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167
gpgme_strsource(rc), gpgme_strerror(rc));
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170
while(engine_info != NULL){
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171
if(engine_info->protocol == GPGME_PROTOCOL_OpenPGP){
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172
gpgme_set_engine_info(GPGME_PROTOCOL_OpenPGP,
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engine_info->file_name, tempdir);
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engine_info->file_name, homedir);
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engine_info = engine_info->next;
215
178
if(engine_info == NULL){
216
fprintf(stderr, "Could not set GPGME home dir to %s\n", tempdir);
220
/* Create new GPGME "context" */
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rc = gpgme_new(&(mc->ctx));
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if (rc != GPG_ERR_NO_ERROR){
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fprintf(stderr, "bad gpgme_new: %s: %s\n",
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gpgme_strsource(rc), gpgme_strerror(rc));
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if (not import_key(pubkey) or not import_key(seckey)){
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* Decrypt OpenPGP data.
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* Returns -1 on error
239
static ssize_t pgp_packet_decrypt (const mandos_context *mc,
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const char *cryptotext,
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gpgme_data_t dh_crypto, dh_plain;
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size_t plaintext_capacity = 0;
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ssize_t plaintext_length = 0;
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fprintf(stderr, "Trying to decrypt OpenPGP data\n");
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fprintf(stderr, "Could not set GPGME home dir to %s\n", homedir);
253
183
/* Create new GPGME data buffer from memory cryptotext */
201
/* Create new GPGME "context" */
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rc = gpgme_new(&ctx);
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if (rc != GPG_ERR_NO_ERROR){
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fprintf(stderr, "bad gpgme_new: %s: %s\n",
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gpgme_strsource(rc), gpgme_strerror(rc));
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plaintext_length = -1;
271
210
/* Decrypt data from the cryptotext data buffer to the plaintext
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rc = gpgme_op_decrypt(mc->ctx, dh_crypto, dh_plain);
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rc = gpgme_op_decrypt(ctx, dh_crypto, dh_plain);
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213
if (rc != GPG_ERR_NO_ERROR){
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214
fprintf(stderr, "bad gpgme_op_decrypt: %s: %s\n",
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215
gpgme_strsource(rc), gpgme_strerror(rc));
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216
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");
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fprintf(stderr, "Unsupported algorithm: %s\n",
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result->unsupported_algorithm);
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fprintf(stderr, "Wrong key usage: %u\n",
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result->wrong_key_usage);
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if(result->file_name != NULL){
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fprintf(stderr, "File name: %s\n", result->file_name);
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gpgme_recipient_t recipient;
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recipient = result->recipients;
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while(recipient != NULL){
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fprintf(stderr, "Public key algorithm: %s\n",
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gpgme_pubkey_algo_name(recipient->pubkey_algo));
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fprintf(stderr, "Key ID: %s\n", recipient->keyid);
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fprintf(stderr, "Secret key available: %s\n",
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recipient->status == GPG_ERR_NO_SECKEY
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recipient = recipient->next;
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217
goto decrypt_end;
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221
fprintf(stderr, "Decryption of OpenPGP data succeeded\n");
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gpgme_decrypt_result_t result;
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result = gpgme_op_decrypt_result(ctx);
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fprintf(stderr, "gpgme_op_decrypt_result failed\n");
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fprintf(stderr, "Unsupported algorithm: %s\n",
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result->unsupported_algorithm);
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fprintf(stderr, "Wrong key usage: %u\n",
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result->wrong_key_usage);
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if(result->file_name != NULL){
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fprintf(stderr, "File name: %s\n", result->file_name);
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gpgme_recipient_t recipient;
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recipient = result->recipients;
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while(recipient != NULL){
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fprintf(stderr, "Public key algorithm: %s\n",
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gpgme_pubkey_algo_name(recipient->pubkey_algo));
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fprintf(stderr, "Key ID: %s\n", recipient->keyid);
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fprintf(stderr, "Secret key available: %s\n",
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recipient->status == GPG_ERR_NO_SECKEY
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recipient = recipient->next;
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/* Seek back to the beginning of the GPGME plaintext data buffer */
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if (gpgme_data_seek(dh_plain, (off_t) 0, SEEK_SET) == -1){
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perror("gpgme_data_seek");
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perror("pgpme_data_seek");
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plaintext_length = -1;
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goto decrypt_end;
822
769
char *connect_to = NULL;
823
char tempdir[] = "/tmp/mandosXXXXXX";
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770
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
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const char *seckey = PATHDIR "/" SECKEY;
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const char *pubkey = PATHDIR "/" PUBKEY;
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char *pubkeyfilename = NULL;
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char *seckeyfilename = NULL;
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const char *pubkeyname = "pubkey.txt";
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const char *seckeyname = "seckey.txt";
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mandos_context mc = { .simple_poll = NULL, .server = NULL,
829
.dh_bits = 1024, .priority = "SECURE256"
830
":!CTYPE-X.509:+CTYPE-OPENPGP" };
776
.dh_bits = 1024, .priority = "SECURE256"};
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bool gnutls_initalized = false;
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bool gpgme_initalized = false;
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780
struct argp_option options[] = {
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781
{ .name = "debug", .key = 128,
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.doc = "Debug mode", .group = 3 },
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783
{ .name = "connect", .key = 'c',
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.arg = "ADDRESS:PORT",
840
.doc = "Connect directly to a specific Mandos server",
785
.doc = "Connect directly to a sepcified mandos server",
842
787
{ .name = "interface", .key = 'i',
844
.doc = "Interface that will be used to search for Mandos"
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.doc = "Interface that Avahi will conntect through",
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{ .name = "keydir", .key = 'd',
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.doc = "Directory where the openpgp keyring is",
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795
{ .name = "seckey", .key = 's',
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.doc = "OpenPGP secret key file base name",
797
.doc = "Secret openpgp key for gnutls authentication",
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799
{ .name = "pubkey", .key = 'p',
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.doc = "OpenPGP public key file base name",
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.doc = "Public openpgp key for gnutls authentication",
855
803
{ .name = "dh-bits", .key = 129,
857
.doc = "Bit length of the prime number used in the"
858
" Diffie-Hellman key exchange",
805
.doc = "dh-bits to use in gnutls communication",
860
807
{ .name = "priority", .key = 130,
862
.doc = "GnuTLS priority string for the TLS handshake",
809
.doc = "GNUTLS priority", .group = 1 },
867
814
error_t parse_opt (int key, char *arg,
868
815
struct argp_state *state) {
816
/* Get the INPUT argument from `argp_parse', which we know is
817
a pointer to our plugin list pointer. */
870
case 128: /* --debug */
873
case 'c': /* --connect */
874
823
connect_to = arg;
876
case 'i': /* --interface */
879
case 's': /* --seckey */
882
case 'p': /* --pubkey */
885
case 129: /* --dh-bits */
886
ret = sscanf(arg, "%u", &mc.dh_bits);
888
fprintf(stderr, "Bad number of DH bits\n");
839
mc.dh_bits = (unsigned int) strtol(arg, NULL, 10);
889
842
exit(EXIT_FAILURE);
892
case 130: /* --priority */
893
846
mc.priority = arg;
895
848
case ARGP_KEY_ARG:
905
858
struct argp argp = { .options = options, .parser = parse_opt,
907
860
.doc = "Mandos client -- Get and decrypt"
908
" passwords from a Mandos server" };
861
" passwords from mandos server" };
909
862
ret = argp_parse (&argp, argc, argv, 0, 0, NULL);
910
863
if (ret == ARGP_ERR_UNKNOWN){
911
864
fprintf(stderr, "Unknown error while parsing arguments\n");
870
pubkeyfilename = combinepath(keydir, pubkeyname);
871
if (pubkeyfilename == NULL){
872
perror("combinepath");
873
exitcode = EXIT_FAILURE;
877
seckeyfilename = combinepath(keydir, seckeyname);
878
if (seckeyfilename == NULL){
879
perror("combinepath");
880
exitcode = EXIT_FAILURE;
884
ret = init_gnutls_global(&mc, pubkeyfilename, seckeyfilename);
886
fprintf(stderr, "init_gnutls_global failed\n");
887
exitcode = EXIT_FAILURE;
890
gnutls_initalized = true;
917
893
/* If the interface is down, bring it up */
957
930
perror("setgid");
960
ret = init_gnutls_global(&mc, pubkey, seckey);
962
fprintf(stderr, "init_gnutls_global failed\n");
963
exitcode = EXIT_FAILURE;
966
gnutls_initalized = true;
969
if(mkdtemp(tempdir) == NULL){
975
if(not init_gpgme(&mc, pubkey, seckey, tempdir)){
976
fprintf(stderr, "gpgme_initalized failed\n");
977
exitcode = EXIT_FAILURE;
980
gpgme_initalized = true;
983
933
if_index = (AvahiIfIndex) if_nametoindex(interface);
984
934
if(if_index == 0){
985
935
fprintf(stderr, "No such interface: \"%s\"\n", interface);
1088
1038
if (mc.server != NULL)
1089
1039
avahi_server_free(mc.server);
1091
1041
if (mc.simple_poll != NULL)
1092
1042
avahi_simple_poll_free(mc.simple_poll);
1043
free(pubkeyfilename);
1044
free(seckeyfilename);
1094
1046
if (gnutls_initalized){
1095
1047
gnutls_certificate_free_credentials(mc.cred);
1096
1048
gnutls_global_deinit ();
1097
gnutls_dh_params_deinit(mc.dh_params);
1100
if(gpgme_initalized){
1101
gpgme_release(mc.ctx);
1104
/* Removes the temp directory used by GPGME */
1105
if(tempdir[0] != '\0'){
1107
struct dirent *direntry;
1108
d = opendir(tempdir);
1110
if(errno != ENOENT){
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);
1138
if(ret == -1 and errno != ENOENT){
1143
1051
return exitcode;