101
49
#include <avahi-common/malloc.h>
102
50
#include <avahi-common/error.h>
105
#include <gnutls/gnutls.h> /* All GnuTLS types, constants and
108
init_gnutls_session(),
110
#include <gnutls/openpgp.h>
111
/* gnutls_certificate_set_openpgp_key_file(),
112
GNUTLS_OPENPGP_FMT_BASE64 */
115
#include <gpgme.h> /* All GPGME types, constants and
118
GPGME_PROTOCOL_OpenPGP,
53
#include <sys/types.h> /* socket(), inet_pton() */
54
#include <sys/socket.h> /* socket(), struct sockaddr_in6,
55
struct in6_addr, inet_pton() */
56
#include <gnutls/gnutls.h> /* All GnuTLS stuff */
57
#include <gnutls/openpgp.h> /* GnuTLS with openpgp stuff */
59
#include <unistd.h> /* close() */
60
#include <netinet/in.h>
61
#include <stdbool.h> /* true */
62
#include <string.h> /* memset */
63
#include <arpa/inet.h> /* inet_pton() */
64
#include <iso646.h> /* not */
67
#include <errno.h> /* perror() */
121
73
#define BUFFER_SIZE 256
123
#define PATHDIR "/conf/conf.d/mandos"
124
#define SECKEY "seckey.txt"
125
#define PUBKEY "pubkey.txt"
75
static const char *keydir = "/conf/conf.d/mandos";
76
static const char *pubkeyfile = "pubkey.txt";
77
static const char *seckeyfile = "seckey.txt";
127
79
bool debug = false;
128
static const char mandos_protocol_version[] = "1";
129
const char *argp_program_version = "mandos-client " VERSION;
130
const char *argp_program_bug_address = "<mandos@recompile.se>";
131
static const char sys_class_net[] = "/sys/class/net";
132
char *connect_to = NULL;
134
/* Doubly linked list that need to be circularly linked when used */
135
typedef struct server{
138
AvahiIfIndex if_index;
140
struct timespec last_seen;
145
/* Used for passing in values through the Avahi callback functions */
81
/* Used for passing in values through all the callback functions */
147
83
AvahiSimplePoll *simple_poll;
148
84
AvahiServer *server;
149
85
gnutls_certificate_credentials_t cred;
150
86
unsigned int dh_bits;
151
gnutls_dh_params_t dh_params;
152
87
const char *priority;
91
* Decrypt OpenPGP data using keyrings in HOMEDIR.
94
static ssize_t pgp_packet_decrypt (const char *cryptotext,
98
gpgme_data_t dh_crypto, dh_plain;
154
server *current_server;
157
/* global context so signal handler can reach it*/
158
mandos_context mc = { .simple_poll = NULL, .server = NULL,
159
.dh_bits = 1024, .priority = "SECURE256"
160
":!CTYPE-X.509:+CTYPE-OPENPGP",
161
.current_server = NULL };
163
sig_atomic_t quit_now = 0;
164
int signal_received = 0;
166
/* Function to use when printing errors */
167
void perror_plus(const char *print_text){
168
fprintf(stderr, "Mandos plugin %s: ",
169
program_invocation_short_name);
174
* Make additional room in "buffer" for at least BUFFER_SIZE more
175
* bytes. "buffer_capacity" is how much is currently allocated,
176
* "buffer_length" is how much is already used.
178
size_t incbuffer(char **buffer, size_t buffer_length,
179
size_t buffer_capacity){
180
if(buffer_length + BUFFER_SIZE > buffer_capacity){
181
*buffer = realloc(*buffer, buffer_capacity + BUFFER_SIZE);
185
buffer_capacity += BUFFER_SIZE;
187
return buffer_capacity;
190
/* Add server to set of servers to retry periodically */
191
int add_server(const char *ip, uint16_t port,
192
AvahiIfIndex if_index,
195
server *new_server = malloc(sizeof(server));
196
if(new_server == NULL){
197
perror_plus("malloc");
200
*new_server = (server){ .ip = strdup(ip),
202
.if_index = if_index,
204
if(new_server->ip == NULL){
205
perror_plus("strdup");
208
/* Special case of first server */
209
if (mc.current_server == NULL){
210
new_server->next = new_server;
211
new_server->prev = new_server;
212
mc.current_server = new_server;
213
/* Place the new server last in the list */
215
new_server->next = mc.current_server;
216
new_server->prev = mc.current_server->prev;
217
new_server->prev->next = new_server;
218
mc.current_server->prev = new_server;
220
ret = clock_gettime(CLOCK_MONOTONIC, &mc.current_server->last_seen);
222
perror_plus("clock_gettime");
231
static bool init_gpgme(const char *seckey,
232
const char *pubkey, const char *tempdir){
233
100
gpgme_error_t rc;
102
ssize_t plaintext_capacity = 0;
103
ssize_t plaintext_length = 0;
234
104
gpgme_engine_info_t engine_info;
238
* Helper function to insert pub and seckey to the engine keyring.
240
bool import_key(const char *filename){
243
gpgme_data_t pgp_data;
245
fd = (int)TEMP_FAILURE_RETRY(open(filename, O_RDONLY));
251
rc = gpgme_data_new_from_fd(&pgp_data, fd);
252
if(rc != GPG_ERR_NO_ERROR){
253
fprintf(stderr, "bad gpgme_data_new_from_fd: %s: %s\n",
254
gpgme_strsource(rc), gpgme_strerror(rc));
258
rc = gpgme_op_import(mc.ctx, pgp_data);
259
if(rc != GPG_ERR_NO_ERROR){
260
fprintf(stderr, "bad gpgme_op_import: %s: %s\n",
261
gpgme_strsource(rc), gpgme_strerror(rc));
265
ret = (int)TEMP_FAILURE_RETRY(close(fd));
267
perror_plus("close");
269
gpgme_data_release(pgp_data);
274
fprintf(stderr, "Initializing GPGME\n");
107
fprintf(stderr, "Trying to decrypt OpenPGP data\n");
278
111
gpgme_check_version(NULL);
279
112
rc = gpgme_engine_check_version(GPGME_PROTOCOL_OpenPGP);
280
if(rc != GPG_ERR_NO_ERROR){
113
if (rc != GPG_ERR_NO_ERROR){
281
114
fprintf(stderr, "bad gpgme_engine_check_version: %s: %s\n",
282
115
gpgme_strsource(rc), gpgme_strerror(rc));
286
119
/* Set GPGME home directory for the OpenPGP engine only */
287
rc = gpgme_get_engine_info(&engine_info);
288
if(rc != GPG_ERR_NO_ERROR){
120
rc = gpgme_get_engine_info (&engine_info);
121
if (rc != GPG_ERR_NO_ERROR){
289
122
fprintf(stderr, "bad gpgme_get_engine_info: %s: %s\n",
290
123
gpgme_strsource(rc), gpgme_strerror(rc));
293
126
while(engine_info != NULL){
294
127
if(engine_info->protocol == GPGME_PROTOCOL_OpenPGP){
295
128
gpgme_set_engine_info(GPGME_PROTOCOL_OpenPGP,
296
engine_info->file_name, tempdir);
129
engine_info->file_name, homedir);
299
132
engine_info = engine_info->next;
301
134
if(engine_info == NULL){
302
fprintf(stderr, "Could not set GPGME home dir to %s\n", tempdir);
306
/* Create new GPGME "context" */
307
rc = gpgme_new(&(mc.ctx));
308
if(rc != GPG_ERR_NO_ERROR){
309
fprintf(stderr, "bad gpgme_new: %s: %s\n",
310
gpgme_strsource(rc), gpgme_strerror(rc));
314
if(not import_key(pubkey) or not import_key(seckey)){
322
* Decrypt OpenPGP data.
323
* Returns -1 on error
325
static ssize_t pgp_packet_decrypt(const char *cryptotext,
328
gpgme_data_t dh_crypto, dh_plain;
331
size_t plaintext_capacity = 0;
332
ssize_t plaintext_length = 0;
335
fprintf(stderr, "Trying to decrypt OpenPGP data\n");
135
fprintf(stderr, "Could not set GPGME home dir to %s\n", homedir);
338
139
/* Create new GPGME data buffer from memory cryptotext */
339
140
rc = gpgme_data_new_from_mem(&dh_crypto, cryptotext, crypto_size,
341
if(rc != GPG_ERR_NO_ERROR){
142
if (rc != GPG_ERR_NO_ERROR){
342
143
fprintf(stderr, "bad gpgme_data_new_from_mem: %s: %s\n",
343
144
gpgme_strsource(rc), gpgme_strerror(rc));
444
260
return plaintext_length;
447
static const char * safer_gnutls_strerror(int value){
448
const char *ret = gnutls_strerror(value); /* Spurious warning from
449
-Wunreachable-code */
263
static const char * safer_gnutls_strerror (int value) {
264
const char *ret = gnutls_strerror (value);
451
266
ret = "(unknown)";
455
/* GnuTLS log function callback */
456
270
static void debuggnutls(__attribute__((unused)) int level,
457
271
const char* string){
458
fprintf(stderr, "GnuTLS: %s", string);
272
fprintf(stderr, "%s", string);
461
static int init_gnutls_global(const char *pubkeyfilename,
462
const char *seckeyfilename){
275
static int initgnutls(mandos_context *mc, gnutls_session_t *session,
276
gnutls_dh_params_t *dh_params){
466
281
fprintf(stderr, "Initializing GnuTLS\n");
469
ret = gnutls_global_init();
470
if(ret != GNUTLS_E_SUCCESS){
471
fprintf(stderr, "GnuTLS global_init: %s\n",
472
safer_gnutls_strerror(ret));
284
if ((ret = gnutls_global_init ())
285
!= GNUTLS_E_SUCCESS) {
286
fprintf (stderr, "global_init: %s\n", safer_gnutls_strerror(ret));
477
/* "Use a log level over 10 to enable all debugging options."
480
291
gnutls_global_set_log_level(11);
481
292
gnutls_global_set_log_function(debuggnutls);
484
/* OpenPGP credentials */
485
ret = gnutls_certificate_allocate_credentials(&mc.cred);
486
if(ret != GNUTLS_E_SUCCESS){
487
fprintf(stderr, "GnuTLS memory error: %s\n",
488
safer_gnutls_strerror(ret));
489
gnutls_global_deinit();
295
/* openpgp credentials */
296
if ((ret = gnutls_certificate_allocate_credentials (&mc->cred))
297
!= GNUTLS_E_SUCCESS) {
298
fprintf (stderr, "memory error: %s\n",
299
safer_gnutls_strerror(ret));
494
fprintf(stderr, "Attempting to use OpenPGP public key %s and"
495
" secret key %s as GnuTLS credentials\n", pubkeyfilename,
304
fprintf(stderr, "Attempting to use OpenPGP certificate %s"
305
" and keyfile %s as GnuTLS credentials\n", pubkeyfile,
499
309
ret = gnutls_certificate_set_openpgp_key_file
500
(mc.cred, pubkeyfilename, seckeyfilename,
501
GNUTLS_OPENPGP_FMT_BASE64);
502
if(ret != GNUTLS_E_SUCCESS){
504
"Error[%d] while reading the OpenPGP key pair ('%s',"
505
" '%s')\n", ret, pubkeyfilename, seckeyfilename);
506
fprintf(stderr, "The GnuTLS error is: %s\n",
507
safer_gnutls_strerror(ret));
511
/* GnuTLS server initialization */
512
ret = gnutls_dh_params_init(&mc.dh_params);
513
if(ret != GNUTLS_E_SUCCESS){
514
fprintf(stderr, "Error in GnuTLS DH parameter initialization:"
515
" %s\n", safer_gnutls_strerror(ret));
518
ret = gnutls_dh_params_generate2(mc.dh_params, mc.dh_bits);
519
if(ret != GNUTLS_E_SUCCESS){
520
fprintf(stderr, "Error in GnuTLS prime generation: %s\n",
521
safer_gnutls_strerror(ret));
525
gnutls_certificate_set_dh_params(mc.cred, mc.dh_params);
531
gnutls_certificate_free_credentials(mc.cred);
532
gnutls_global_deinit();
533
gnutls_dh_params_deinit(mc.dh_params);
537
static int init_gnutls_session(gnutls_session_t *session){
539
/* GnuTLS session creation */
541
ret = gnutls_init(session, GNUTLS_SERVER);
545
} while(ret == GNUTLS_E_INTERRUPTED or ret == GNUTLS_E_AGAIN);
546
if(ret != GNUTLS_E_SUCCESS){
310
(mc->cred, pubkeyfile, seckeyfile, GNUTLS_OPENPGP_FMT_BASE64);
311
if (ret != GNUTLS_E_SUCCESS) {
313
(stderr, "Error[%d] while reading the OpenPGP key pair ('%s',"
315
ret, pubkeyfile, seckeyfile);
316
fprintf(stdout, "The Error is: %s\n",
317
safer_gnutls_strerror(ret));
321
//GnuTLS server initialization
322
if ((ret = gnutls_dh_params_init(dh_params))
323
!= GNUTLS_E_SUCCESS) {
324
fprintf (stderr, "Error in dh parameter initialization: %s\n",
325
safer_gnutls_strerror(ret));
329
if ((ret = gnutls_dh_params_generate2(*dh_params, mc->dh_bits))
330
!= GNUTLS_E_SUCCESS) {
331
fprintf (stderr, "Error in prime generation: %s\n",
332
safer_gnutls_strerror(ret));
336
gnutls_certificate_set_dh_params(mc->cred, *dh_params);
338
// GnuTLS session creation
339
if ((ret = gnutls_init(session, GNUTLS_SERVER))
340
!= GNUTLS_E_SUCCESS){
547
341
fprintf(stderr, "Error in GnuTLS session initialization: %s\n",
548
342
safer_gnutls_strerror(ret));
554
ret = gnutls_priority_set_direct(*session, mc.priority, &err);
556
gnutls_deinit(*session);
559
} while(ret == GNUTLS_E_INTERRUPTED or ret == GNUTLS_E_AGAIN);
560
if(ret != GNUTLS_E_SUCCESS){
561
fprintf(stderr, "Syntax error at: %s\n", err);
562
fprintf(stderr, "GnuTLS error: %s\n",
563
safer_gnutls_strerror(ret));
564
gnutls_deinit(*session);
345
if ((ret = gnutls_priority_set_direct(*session, mc->priority, &err))
346
!= GNUTLS_E_SUCCESS) {
347
fprintf(stderr, "Syntax error at: %s\n", err);
348
fprintf(stderr, "GnuTLS error: %s\n",
349
safer_gnutls_strerror(ret));
570
ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,
573
gnutls_deinit(*session);
576
} while(ret == GNUTLS_E_INTERRUPTED or ret == GNUTLS_E_AGAIN);
577
if(ret != GNUTLS_E_SUCCESS){
578
fprintf(stderr, "Error setting GnuTLS credentials: %s\n",
353
if ((ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,
355
!= GNUTLS_E_SUCCESS) {
356
fprintf(stderr, "Error setting a credentials set: %s\n",
579
357
safer_gnutls_strerror(ret));
580
gnutls_deinit(*session);
584
361
/* ignore client certificate if any. */
585
gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);
362
gnutls_certificate_server_set_request (*session,
587
gnutls_dh_set_prime_bits(*session, mc.dh_bits);
365
gnutls_dh_set_prime_bits (*session, mc->dh_bits);
592
/* Avahi log function callback */
593
370
static void empty_log(__attribute__((unused)) AvahiLogLevel level,
594
371
__attribute__((unused)) const char *txt){}
596
/* Called when a Mandos server is found */
597
373
static int start_mandos_communication(const char *ip, uint16_t port,
598
374
AvahiIfIndex if_index,
600
int ret, tcp_sd = -1;
603
struct sockaddr_in in;
604
struct sockaddr_in6 in6;
377
struct sockaddr_in6 to;
606
378
char *buffer = NULL;
607
char *decrypted_buffer = NULL;
379
char *decrypted_buffer;
608
380
size_t buffer_length = 0;
609
381
size_t buffer_capacity = 0;
382
ssize_t decrypted_buffer_size;
385
char interface[IF_NAMESIZE];
612
386
gnutls_session_t session;
613
int pf; /* Protocol family */
630
fprintf(stderr, "Bad address family: %d\n", af);
635
ret = init_gnutls_session(&session);
641
fprintf(stderr, "Setting up a TCP connection to %s, port %" PRIu16
645
tcp_sd = socket(pf, SOCK_STREAM, 0);
648
perror_plus("socket");
658
memset(&to, 0, sizeof(to));
660
to.in6.sin6_family = (sa_family_t)af;
661
ret = inet_pton(af, ip, &to.in6.sin6_addr);
663
to.in.sin_family = (sa_family_t)af;
664
ret = inet_pton(af, ip, &to.in.sin_addr);
668
perror_plus("inet_pton");
387
gnutls_dh_params_t dh_params;
390
fprintf(stderr, "Setting up a tcp connection to %s, port %d\n",
394
tcp_sd = socket(PF_INET6, SOCK_STREAM, 0);
401
if(if_indextoname((unsigned int)if_index, interface) == NULL){
402
perror("if_indextoname");
405
fprintf(stderr, "Binding to interface %s\n", interface);
408
memset(&to,0,sizeof(to)); /* Spurious warning */
409
to.sin6_family = AF_INET6;
410
ret = inet_pton(AF_INET6, ip, &to.sin6_addr);
674
416
fprintf(stderr, "Bad address: %s\n", ip);
679
to.in6.sin6_port = htons(port); /* Spurious warnings from
681
-Wunreachable-code */
683
if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */
684
(&to.in6.sin6_addr)){ /* -Wstrict-aliasing=2 or lower and
686
if(if_index == AVAHI_IF_UNSPEC){
687
fprintf(stderr, "An IPv6 link-local address is incomplete"
688
" without a network interface\n");
692
/* Set the network interface number as scope */
693
to.in6.sin6_scope_id = (uint32_t)if_index;
696
to.in.sin_port = htons(port); /* Spurious warnings from
698
-Wunreachable-code */
419
to.sin6_port = htons(port); /* Spurious warning */
421
to.sin6_scope_id = (uint32_t)if_index;
707
if(af == AF_INET6 and if_index != AVAHI_IF_UNSPEC){
708
char interface[IF_NAMESIZE];
709
if(if_indextoname((unsigned int)if_index, interface) == NULL){
710
perror_plus("if_indextoname");
712
fprintf(stderr, "Connection to: %s%%%s, port %" PRIu16 "\n",
713
ip, interface, port);
716
fprintf(stderr, "Connection to: %s, port %" PRIu16 "\n", ip,
719
char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?
720
INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";
723
pcret = inet_ntop(af, &(to.in6.sin6_addr), addrstr,
726
pcret = inet_ntop(af, &(to.in.sin_addr), addrstr,
730
perror_plus("inet_ntop");
424
fprintf(stderr, "Connection to: %s, port %d\n", ip, port);
425
char addrstr[INET6_ADDRSTRLEN] = "";
426
if(inet_ntop(to.sin6_family, &(to.sin6_addr), addrstr,
427
sizeof(addrstr)) == NULL){
732
430
if(strcmp(addrstr, ip) != 0){
733
431
fprintf(stderr, "Canonical address form: %s\n", addrstr);
1064
642
case AVAHI_BROWSER_ALL_FOR_NOW:
1065
643
case AVAHI_BROWSER_CACHE_EXHAUSTED:
1067
fprintf(stderr, "No Mandos server found, still searching...\n");
1073
/* Signal handler that stops main loop after SIGTERM */
1074
static void handle_sigterm(int sig){
1079
signal_received = sig;
1080
int old_errno = errno;
1081
/* set main loop to exit */
1082
if(mc.simple_poll != NULL){
1083
avahi_simple_poll_quit(mc.simple_poll);
1089
* This function determines if a directory entry in /sys/class/net
1090
* corresponds to an acceptable network device.
1091
* (This function is passed to scandir(3) as a filter function.)
1093
int good_interface(const struct dirent *if_entry){
1095
char *flagname = NULL;
1096
if(if_entry->d_name[0] == '.'){
1099
int ret = asprintf(&flagname, "%s/%s/flags", sys_class_net,
1102
perror_plus("asprintf");
1105
int flags_fd = (int)TEMP_FAILURE_RETRY(open(flagname, O_RDONLY));
1107
perror_plus("open");
1112
typedef short ifreq_flags; /* ifreq.ifr_flags in netdevice(7) */
1113
/* read line from flags_fd */
1114
ssize_t to_read = 2+(sizeof(ifreq_flags)*2)+1; /* "0x1003\n" */
1115
char *flagstring = malloc((size_t)to_read+1); /* +1 for final \0 */
1116
flagstring[(size_t)to_read] = '\0';
1117
if(flagstring == NULL){
1118
perror_plus("malloc");
1123
ssret = (ssize_t)TEMP_FAILURE_RETRY(read(flags_fd, flagstring,
1126
perror_plus("read");
1140
tmpmax = strtoimax(flagstring, &tmp, 0);
1141
if(errno != 0 or tmp == flagstring or (*tmp != '\0'
1142
and not (isspace(*tmp)))
1143
or tmpmax != (ifreq_flags)tmpmax){
1145
fprintf(stderr, "Invalid flags \"%s\" for interface \"%s\"\n",
1146
flagstring, if_entry->d_name);
1152
ifreq_flags flags = (ifreq_flags)tmpmax;
1153
/* Reject the loopback device */
1154
if(flags & IFF_LOOPBACK){
1156
fprintf(stderr, "Rejecting loopback interface \"%s\"\n",
1161
/* Accept point-to-point devices only if connect_to is specified */
1162
if(connect_to != NULL and (flags & IFF_POINTOPOINT)){
1164
fprintf(stderr, "Accepting point-to-point interface \"%s\"\n",
1169
/* Otherwise, reject non-broadcast-capable devices */
1170
if(not (flags & IFF_BROADCAST)){
1172
fprintf(stderr, "Rejecting non-broadcast interface \"%s\"\n",
1177
/* Reject non-ARP interfaces (including dummy interfaces) */
1178
if(flags & IFF_NOARP){
1180
fprintf(stderr, "Rejecting non-ARP interface \"%s\"\n",
1185
/* Accept this device */
1187
fprintf(stderr, "Interface \"%s\" is acceptable\n",
1193
int notdotentries(const struct dirent *direntry){
1194
/* Skip "." and ".." */
1195
if(direntry->d_name[0] == '.'
1196
and (direntry->d_name[1] == '\0'
1197
or (direntry->d_name[1] == '.'
1198
and direntry->d_name[2] == '\0'))){
1204
int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval){
1206
struct timespec now;
1207
struct timespec waited_time;
1208
intmax_t block_time;
1211
if(mc.current_server == NULL){
1214
"Wait until first server is found. No timeout!\n");
1216
ret = avahi_simple_poll_iterate(s, -1);
1219
fprintf(stderr, "Check current_server if we should run it,"
1222
/* the current time */
1223
ret = clock_gettime(CLOCK_MONOTONIC, &now);
1225
perror_plus("clock_gettime");
1228
/* Calculating in ms how long time between now and server
1229
who we visted longest time ago. Now - last seen. */
1230
waited_time.tv_sec = (now.tv_sec
1231
- mc.current_server->last_seen.tv_sec);
1232
waited_time.tv_nsec = (now.tv_nsec
1233
- mc.current_server->last_seen.tv_nsec);
1234
/* total time is 10s/10,000ms.
1235
Converting to s from ms by dividing by 1,000,
1236
and ns to ms by dividing by 1,000,000. */
1237
block_time = ((retry_interval
1238
- ((intmax_t)waited_time.tv_sec * 1000))
1239
- ((intmax_t)waited_time.tv_nsec / 1000000));
1242
fprintf(stderr, "Blocking for %" PRIdMAX " ms\n", block_time);
1245
if(block_time <= 0){
1246
ret = start_mandos_communication(mc.current_server->ip,
1247
mc.current_server->port,
1248
mc.current_server->if_index,
1249
mc.current_server->af);
1251
avahi_simple_poll_quit(mc.simple_poll);
1254
ret = clock_gettime(CLOCK_MONOTONIC,
1255
&mc.current_server->last_seen);
1257
perror_plus("clock_gettime");
1260
mc.current_server = mc.current_server->next;
1261
block_time = 0; /* Call avahi to find new Mandos
1262
servers, but don't block */
1265
ret = avahi_simple_poll_iterate(s, (int)block_time);
1268
if (ret > 0 or errno != EINTR) {
1269
return (ret != 1) ? ret : 0;
1275
int main(int argc, char *argv[]){
1276
AvahiSServiceBrowser *sb = NULL;
1281
int exitcode = EXIT_SUCCESS;
1282
const char *interface = "";
1283
struct ifreq network;
1285
bool take_down_interface = false;
1288
char tempdir[] = "/tmp/mandosXXXXXX";
1289
bool tempdir_created = false;
1290
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
1291
const char *seckey = PATHDIR "/" SECKEY;
1292
const char *pubkey = PATHDIR "/" PUBKEY;
1294
bool gnutls_initialized = false;
1295
bool gpgme_initialized = false;
1297
double retry_interval = 10; /* 10s between trying a server and
1298
retrying the same server again */
1300
struct sigaction old_sigterm_action = { .sa_handler = SIG_DFL };
1301
struct sigaction sigterm_action = { .sa_handler = handle_sigterm };
1306
/* Lower any group privileges we might have, just to be safe */
1310
perror_plus("setgid");
1313
/* Lower user privileges (temporarily) */
1317
perror_plus("seteuid");
1325
struct argp_option options[] = {
1326
{ .name = "debug", .key = 128,
1327
.doc = "Debug mode", .group = 3 },
1328
{ .name = "connect", .key = 'c',
1329
.arg = "ADDRESS:PORT",
1330
.doc = "Connect directly to a specific Mandos server",
1332
{ .name = "interface", .key = 'i',
1334
.doc = "Network interface that will be used to search for"
1337
{ .name = "seckey", .key = 's',
1339
.doc = "OpenPGP secret key file base name",
1341
{ .name = "pubkey", .key = 'p',
1343
.doc = "OpenPGP public key file base name",
1345
{ .name = "dh-bits", .key = 129,
1347
.doc = "Bit length of the prime number used in the"
1348
" Diffie-Hellman key exchange",
1350
{ .name = "priority", .key = 130,
1352
.doc = "GnuTLS priority string for the TLS handshake",
1354
{ .name = "delay", .key = 131,
1356
.doc = "Maximum delay to wait for interface startup",
1358
{ .name = "retry", .key = 132,
1360
.doc = "Retry interval used when denied by the mandos server",
1363
* These reproduce what we would get without ARGP_NO_HELP
1365
{ .name = "help", .key = '?',
1366
.doc = "Give this help list", .group = -1 },
1367
{ .name = "usage", .key = -3,
1368
.doc = "Give a short usage message", .group = -1 },
1369
{ .name = "version", .key = 'V',
1370
.doc = "Print program version", .group = -1 },
648
/* Combines file name and path and returns the malloced new
649
string. some sane checks could/should be added */
650
static const char *combinepath(const char *first, const char *second){
651
size_t f_len = strlen(first);
652
size_t s_len = strlen(second);
653
char *tmp = malloc(f_len + s_len + 2);
658
memcpy(tmp, first, f_len); /* Spurious warning */
662
memcpy(tmp + f_len + 1, second, s_len); /* Spurious warning */
664
tmp[f_len + 1 + s_len] = '\0';
669
int main(AVAHI_GCC_UNUSED int argc, AVAHI_GCC_UNUSED char*argv[]) {
670
AvahiServerConfig config;
671
AvahiSServiceBrowser *sb = NULL;
675
int returncode = EXIT_SUCCESS;
676
const char *interface = "eth0";
677
struct ifreq network;
679
char *connect_to = NULL;
680
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
681
mandos_context mc = { .simple_poll = NULL, .server = NULL,
682
.dh_bits = 1024, .priority = "SECURE256"};
1374
error_t parse_opt(int key, char *arg,
1375
struct argp_state *state){
1378
case 128: /* --debug */
1381
case 'c': /* --connect */
1384
case 'i': /* --interface */
1387
case 's': /* --seckey */
1390
case 'p': /* --pubkey */
1393
case 129: /* --dh-bits */
1395
tmpmax = strtoimax(arg, &tmp, 10);
1396
if(errno != 0 or tmp == arg or *tmp != '\0'
1397
or tmpmax != (typeof(mc.dh_bits))tmpmax){
1398
argp_error(state, "Bad number of DH bits");
1400
mc.dh_bits = (typeof(mc.dh_bits))tmpmax;
1402
case 130: /* --priority */
1405
case 131: /* --delay */
1407
delay = strtof(arg, &tmp);
1408
if(errno != 0 or tmp == arg or *tmp != '\0'){
1409
argp_error(state, "Bad delay");
1411
case 132: /* --retry */
1413
retry_interval = strtod(arg, &tmp);
1414
if(errno != 0 or tmp == arg or *tmp != '\0'
1415
or (retry_interval * 1000) > INT_MAX
1416
or retry_interval < 0){
1417
argp_error(state, "Bad retry interval");
1421
* These reproduce what we would get without ARGP_NO_HELP
1423
case '?': /* --help */
1424
argp_state_help(state, state->out_stream,
1425
(ARGP_HELP_STD_HELP | ARGP_HELP_EXIT_ERR)
1426
& ~(unsigned int)ARGP_HELP_EXIT_OK);
1427
case -3: /* --usage */
1428
argp_state_help(state, state->out_stream,
1429
ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);
1430
case 'V': /* --version */
1431
fprintf(state->out_stream, "%s\n", argp_program_version);
1432
exit(argp_err_exit_status);
684
debug_int = debug ? 1 : 0;
686
struct option long_options[] = {
687
{"debug", no_argument, &debug_int, 1},
688
{"connect", required_argument, NULL, 'c'},
689
{"interface", required_argument, NULL, 'i'},
690
{"keydir", required_argument, NULL, 'd'},
691
{"seckey", required_argument, NULL, 's'},
692
{"pubkey", required_argument, NULL, 'p'},
693
{"dh-bits", required_argument, NULL, 'D'},
694
{"priority", required_argument, NULL, 'P'},
697
int option_index = 0;
698
ret = getopt_long (argc, argv, "i:", long_options,
725
mc.dh_bits = (unsigned int) strtol(optarg, NULL, 10);
732
mc.priority = optarg;
1435
return ARGP_ERR_UNKNOWN;
1440
struct argp argp = { .options = options, .parser = parse_opt,
1442
.doc = "Mandos client -- Get and decrypt"
1443
" passwords from a Mandos server" };
1444
ret = argp_parse(&argp, argc, argv,
1445
ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);
1452
perror_plus("argp_parse");
1453
exitcode = EX_OSERR;
1456
exitcode = EX_USAGE;
1462
/* Work around Debian bug #633582:
1463
<http://bugs.debian.org/633582> */
1466
/* Re-raise priviliges */
1470
perror_plus("seteuid");
1473
if(strcmp(seckey, PATHDIR "/" SECKEY) == 0){
1474
int seckey_fd = open(seckey, O_RDONLY);
1475
if(seckey_fd == -1){
1476
perror_plus("open");
1478
ret = (int)TEMP_FAILURE_RETRY(fstat(seckey_fd, &st));
1480
perror_plus("fstat");
1482
if(S_ISREG(st.st_mode) and st.st_uid == 0 and st.st_gid == 0){
1483
ret = fchown(seckey_fd, uid, gid);
1485
perror_plus("fchown");
1489
TEMP_FAILURE_RETRY(close(seckey_fd));
1493
if(strcmp(pubkey, PATHDIR "/" PUBKEY) == 0){
1494
int pubkey_fd = open(pubkey, O_RDONLY);
1495
if(pubkey_fd == -1){
1496
perror_plus("open");
1498
ret = (int)TEMP_FAILURE_RETRY(fstat(pubkey_fd, &st));
1500
perror_plus("fstat");
1502
if(S_ISREG(st.st_mode) and st.st_uid == 0 and st.st_gid == 0){
1503
ret = fchown(pubkey_fd, uid, gid);
1505
perror_plus("fchown");
1509
TEMP_FAILURE_RETRY(close(pubkey_fd));
1513
/* Lower privileges */
1517
perror_plus("seteuid");
1522
avahi_set_log_function(empty_log);
1525
if(interface[0] == '\0'){
1526
struct dirent **direntries;
1527
ret = scandir(sys_class_net, &direntries, good_interface,
1530
/* Pick the first good interface */
1531
interface = strdup(direntries[0]->d_name);
1533
fprintf(stderr, "Using interface \"%s\"\n", interface);
1535
if(interface == NULL){
1536
perror_plus("malloc");
1538
exitcode = EXIT_FAILURE;
1544
fprintf(stderr, "Could not find a network interface\n");
1545
exitcode = EXIT_FAILURE;
1550
/* Initialize Avahi early so avahi_simple_poll_quit() can be called
1551
from the signal handler */
1552
/* Initialize the pseudo-RNG for Avahi */
1553
srand((unsigned int) time(NULL));
1554
mc.simple_poll = avahi_simple_poll_new();
1555
if(mc.simple_poll == NULL){
1556
fprintf(stderr, "Avahi: Failed to create simple poll object.\n");
1557
exitcode = EX_UNAVAILABLE;
1561
sigemptyset(&sigterm_action.sa_mask);
1562
ret = sigaddset(&sigterm_action.sa_mask, SIGINT);
1564
perror_plus("sigaddset");
1565
exitcode = EX_OSERR;
1568
ret = sigaddset(&sigterm_action.sa_mask, SIGHUP);
1570
perror_plus("sigaddset");
1571
exitcode = EX_OSERR;
1574
ret = sigaddset(&sigterm_action.sa_mask, SIGTERM);
1576
perror_plus("sigaddset");
1577
exitcode = EX_OSERR;
1580
/* Need to check if the handler is SIG_IGN before handling:
1581
| [[info:libc:Initial Signal Actions]] |
1582
| [[info:libc:Basic Signal Handling]] |
1584
ret = sigaction(SIGINT, NULL, &old_sigterm_action);
1586
perror_plus("sigaction");
1589
if(old_sigterm_action.sa_handler != SIG_IGN){
1590
ret = sigaction(SIGINT, &sigterm_action, NULL);
1592
perror_plus("sigaction");
1593
exitcode = EX_OSERR;
1597
ret = sigaction(SIGHUP, NULL, &old_sigterm_action);
1599
perror_plus("sigaction");
1602
if(old_sigterm_action.sa_handler != SIG_IGN){
1603
ret = sigaction(SIGHUP, &sigterm_action, NULL);
1605
perror_plus("sigaction");
1606
exitcode = EX_OSERR;
1610
ret = sigaction(SIGTERM, NULL, &old_sigterm_action);
1612
perror_plus("sigaction");
1615
if(old_sigterm_action.sa_handler != SIG_IGN){
1616
ret = sigaction(SIGTERM, &sigterm_action, NULL);
1618
perror_plus("sigaction");
1619
exitcode = EX_OSERR;
1624
/* If the interface is down, bring it up */
1625
if(strcmp(interface, "none") != 0){
739
debug = debug_int ? true : false;
741
pubkeyfile = combinepath(keydir, pubkeyfile);
742
if (pubkeyfile == NULL){
743
perror("combinepath");
744
returncode = EXIT_FAILURE;
748
seckeyfile = combinepath(keydir, seckeyfile);
749
if (seckeyfile == NULL){
750
perror("combinepath");
1626
754
if_index = (AvahiIfIndex) if_nametoindex(interface);
1627
755
if(if_index == 0){
1628
756
fprintf(stderr, "No such interface: \"%s\"\n", interface);
1629
exitcode = EX_UNAVAILABLE;
1637
/* Re-raise priviliges */
1641
perror_plus("seteuid");
1645
/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO
1646
messages about the network interface to mess up the prompt */
1647
ret = klogctl(8, NULL, 5);
1648
bool restore_loglevel = true;
1650
restore_loglevel = false;
1651
perror_plus("klogctl");
1653
#endif /* __linux__ */
760
if(connect_to != NULL){
761
/* Connect directly, do not use Zeroconf */
762
/* (Mainly meant for debugging) */
763
char *address = strrchr(connect_to, ':');
765
fprintf(stderr, "No colon in address\n");
769
uint16_t port = (uint16_t) strtol(address+1, NULL, 10);
771
perror("Bad port number");
775
address = connect_to;
776
ret = start_mandos_communication(address, port, if_index, &mc);
1655
784
sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1657
perror_plus("socket");
1658
exitcode = EX_OSERR;
1660
if(restore_loglevel){
1661
ret = klogctl(7, NULL, 0);
1663
perror_plus("klogctl");
1666
#endif /* __linux__ */
1667
/* Lower privileges */
1671
perror_plus("seteuid");
787
returncode = EXIT_FAILURE;
1675
strcpy(network.ifr_name, interface);
790
strcpy(network.ifr_name, interface); /* Spurious warning */
1676
791
ret = ioctl(sd, SIOCGIFFLAGS, &network);
1678
perror_plus("ioctl SIOCGIFFLAGS");
1680
if(restore_loglevel){
1681
ret = klogctl(7, NULL, 0);
1683
perror_plus("klogctl");
1686
#endif /* __linux__ */
1687
exitcode = EX_OSERR;
1688
/* Lower privileges */
1692
perror_plus("seteuid");
794
perror("ioctl SIOCGIFFLAGS");
795
returncode = EXIT_FAILURE;
1696
798
if((network.ifr_flags & IFF_UP) == 0){
1697
799
network.ifr_flags |= IFF_UP;
1698
take_down_interface = true;
1699
800
ret = ioctl(sd, SIOCSIFFLAGS, &network);
1701
take_down_interface = false;
1702
perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");
1703
exitcode = EX_OSERR;
1705
if(restore_loglevel){
1706
ret = klogctl(7, NULL, 0);
1708
perror_plus("klogctl");
1711
#endif /* __linux__ */
1712
/* Lower privileges */
1716
perror_plus("seteuid");
1721
/* Sleep checking until interface is running.
1722
Check every 0.25s, up to total time of delay */
1723
for(int i=0; i < delay * 4; i++){
1724
ret = ioctl(sd, SIOCGIFFLAGS, &network);
1726
perror_plus("ioctl SIOCGIFFLAGS");
1727
} else if(network.ifr_flags & IFF_RUNNING){
1730
struct timespec sleeptime = { .tv_nsec = 250000000 };
1731
ret = nanosleep(&sleeptime, NULL);
1732
if(ret == -1 and errno != EINTR){
1733
perror_plus("nanosleep");
1736
if(not take_down_interface){
1737
/* We won't need the socket anymore */
1738
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1740
perror_plus("close");
1744
if(restore_loglevel){
1745
/* Restores kernel loglevel to default */
1746
ret = klogctl(7, NULL, 0);
1748
perror_plus("klogctl");
1751
#endif /* __linux__ */
1752
/* Lower privileges */
1754
if(take_down_interface){
1755
/* Lower privileges */
1758
perror_plus("seteuid");
1761
/* Lower privileges permanently */
1764
perror_plus("setuid");
1773
ret = init_gnutls_global(pubkey, seckey);
1775
fprintf(stderr, "init_gnutls_global failed\n");
1776
exitcode = EX_UNAVAILABLE;
1779
gnutls_initialized = true;
1786
if(mkdtemp(tempdir) == NULL){
1787
perror_plus("mkdtemp");
1790
tempdir_created = true;
1796
if(not init_gpgme(pubkey, seckey, tempdir)){
1797
fprintf(stderr, "init_gpgme failed\n");
1798
exitcode = EX_UNAVAILABLE;
1801
gpgme_initialized = true;
1808
if(connect_to != NULL){
1809
/* Connect directly, do not use Zeroconf */
1810
/* (Mainly meant for debugging) */
1811
char *address = strrchr(connect_to, ':');
1812
if(address == NULL){
1813
fprintf(stderr, "No colon in address\n");
1814
exitcode = EX_USAGE;
1824
tmpmax = strtoimax(address+1, &tmp, 10);
1825
if(errno != 0 or tmp == address+1 or *tmp != '\0'
1826
or tmpmax != (uint16_t)tmpmax){
1827
fprintf(stderr, "Bad port number\n");
1828
exitcode = EX_USAGE;
1836
port = (uint16_t)tmpmax;
1838
/* Colon in address indicates IPv6 */
1840
if(strchr(connect_to, ':') != NULL){
1842
/* Accept [] around IPv6 address - see RFC 5952 */
1843
if(connect_to[0] == '[' and address[-1] == ']')
1851
address = connect_to;
1857
while(not quit_now){
1858
ret = start_mandos_communication(address, port, if_index, af);
1859
if(quit_now or ret == 0){
1863
fprintf(stderr, "Retrying in %d seconds\n",
1864
(int)retry_interval);
1866
sleep((int)retry_interval);
1870
exitcode = EXIT_SUCCESS;
1881
AvahiServerConfig config;
1882
/* Do not publish any local Zeroconf records */
802
perror("ioctl SIOCSIFFLAGS");
803
returncode = EXIT_FAILURE;
810
avahi_set_log_function(empty_log);
813
/* Initialize the psuedo-RNG */
814
srand((unsigned int) time(NULL));
816
/* Allocate main loop object */
817
if (!(mc.simple_poll = avahi_simple_poll_new())) {
818
fprintf(stderr, "Failed to create simple poll object.\n");
819
returncode = EXIT_FAILURE;
823
/* Do not publish any local records */
1883
824
avahi_server_config_init(&config);
1884
825
config.publish_hinfo = 0;
1885
826
config.publish_addresses = 0;
1886
827
config.publish_workstation = 0;
1887
828
config.publish_domain = 0;
1889
830
/* Allocate a new server */
1890
mc.server = avahi_server_new(avahi_simple_poll_get
1891
(mc.simple_poll), &config, NULL,
831
mc.server=avahi_server_new(avahi_simple_poll_get(mc.simple_poll),
832
&config, NULL, NULL, &error);
1894
/* Free the Avahi configuration data */
834
/* Free the configuration data */
1895
835
avahi_server_config_free(&config);
1898
/* Check if creating the Avahi server object succeeded */
1899
if(mc.server == NULL){
1900
fprintf(stderr, "Failed to create Avahi server: %s\n",
1901
avahi_strerror(error));
1902
exitcode = EX_UNAVAILABLE;
1910
/* Create the Avahi service browser */
1911
sb = avahi_s_service_browser_new(mc.server, if_index,
1912
AVAHI_PROTO_UNSPEC, "_mandos._tcp",
1913
NULL, 0, browse_callback, NULL);
1915
fprintf(stderr, "Failed to create service browser: %s\n",
1916
avahi_strerror(avahi_server_errno(mc.server)));
1917
exitcode = EX_UNAVAILABLE;
1925
/* Run the main loop */
1928
fprintf(stderr, "Starting Avahi loop search\n");
1931
ret = avahi_loop_with_timeout(mc.simple_poll,
1932
(int)(retry_interval * 1000));
1934
fprintf(stderr, "avahi_loop_with_timeout exited %s\n",
1935
(ret == 0) ? "successfully" : "with error");
1941
fprintf(stderr, "%s exiting\n", argv[0]);
1944
/* Cleanup things */
1946
avahi_s_service_browser_free(sb);
1948
if(mc.server != NULL)
1949
avahi_server_free(mc.server);
1951
if(mc.simple_poll != NULL)
1952
avahi_simple_poll_free(mc.simple_poll);
1954
if(gnutls_initialized){
1955
gnutls_certificate_free_credentials(mc.cred);
1956
gnutls_global_deinit();
1957
gnutls_dh_params_deinit(mc.dh_params);
1960
if(gpgme_initialized){
1961
gpgme_release(mc.ctx);
1964
/* Cleans up the circular linked list of Mandos servers the client
1966
if(mc.current_server != NULL){
1967
mc.current_server->prev->next = NULL;
1968
while(mc.current_server != NULL){
1969
server *next = mc.current_server->next;
1970
free(mc.current_server);
1971
mc.current_server = next;
1975
/* Take down the network interface */
1976
if(take_down_interface){
1977
/* Re-raise priviliges */
1981
perror_plus("seteuid");
1984
ret = ioctl(sd, SIOCGIFFLAGS, &network);
1986
perror_plus("ioctl SIOCGIFFLAGS");
1987
} else if(network.ifr_flags & IFF_UP) {
1988
network.ifr_flags &= ~(short)IFF_UP; /* clear flag */
1989
ret = ioctl(sd, SIOCSIFFLAGS, &network);
1991
perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");
1994
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1996
perror_plus("close");
1998
/* Lower privileges permanently */
2002
perror_plus("setuid");
2007
/* Removes the GPGME temp directory and all files inside */
2008
if(tempdir_created){
2009
struct dirent **direntries = NULL;
2010
struct dirent *direntry = NULL;
2011
int numentries = scandir(tempdir, &direntries, notdotentries,
2013
if (numentries > 0){
2014
for(int i = 0; i < numentries; i++){
2015
direntry = direntries[i];
2016
char *fullname = NULL;
2017
ret = asprintf(&fullname, "%s/%s", tempdir,
2020
perror_plus("asprintf");
2023
ret = remove(fullname);
2025
fprintf(stderr, "remove(\"%s\"): %s\n", fullname,
2032
/* need to clean even if 0 because man page doesn't specify */
2034
if (numentries == -1){
2035
perror_plus("scandir");
2037
ret = rmdir(tempdir);
2038
if(ret == -1 and errno != ENOENT){
2039
perror_plus("rmdir");
2044
sigemptyset(&old_sigterm_action.sa_mask);
2045
old_sigterm_action.sa_handler = SIG_DFL;
2046
ret = (int)TEMP_FAILURE_RETRY(sigaction(signal_received,
2047
&old_sigterm_action,
2050
perror_plus("sigaction");
2053
ret = raise(signal_received);
2054
} while(ret != 0 and errno == EINTR);
2056
perror_plus("raise");
2059
TEMP_FAILURE_RETRY(pause());
837
/* Check if creating the server object succeeded */
839
fprintf(stderr, "Failed to create server: %s\n",
840
avahi_strerror(error));
841
returncode = EXIT_FAILURE;
845
/* Create the service browser */
846
sb = avahi_s_service_browser_new(mc.server, if_index,
848
"_mandos._tcp", NULL, 0,
849
browse_callback, &mc);
851
fprintf(stderr, "Failed to create service browser: %s\n",
852
avahi_strerror(avahi_server_errno(mc.server)));
853
returncode = EXIT_FAILURE;
857
/* Run the main loop */
860
fprintf(stderr, "Starting avahi loop search\n");
863
avahi_simple_poll_loop(mc.simple_poll);
868
fprintf(stderr, "%s exiting\n", argv[0]);
873
avahi_s_service_browser_free(sb);
876
avahi_server_free(mc.server);
879
avahi_simple_poll_free(mc.simple_poll);