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@fukt.bsnet.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
int add_server(const char *ip, uint16_t port,
191
AvahiIfIndex if_index,
194
server *new_server = malloc(sizeof(server));
195
if(new_server == NULL){
196
perror_plus("malloc");
199
*new_server = (server){ .ip = strdup(ip),
201
.if_index = if_index,
203
if(new_server->ip == NULL){
204
perror_plus("strdup");
207
/* unique case of first server */
208
if (mc.current_server == NULL){
209
new_server->next = new_server;
210
new_server->prev = new_server;
211
mc.current_server = new_server;
212
/* Placing the new server last in the list */
214
new_server->next = mc.current_server;
215
new_server->prev = mc.current_server->prev;
216
new_server->prev->next = new_server;
217
mc.current_server->prev = new_server;
219
ret = clock_gettime(CLOCK_MONOTONIC, &mc.current_server->last_seen);
221
perror_plus("clock_gettime");
230
static bool init_gpgme(const char *seckey,
231
const char *pubkey, const char *tempdir){
232
100
gpgme_error_t rc;
102
ssize_t plaintext_capacity = 0;
103
ssize_t plaintext_length = 0;
233
104
gpgme_engine_info_t engine_info;
237
* Helper function to insert pub and seckey to the engine keyring.
239
bool import_key(const char *filename){
242
gpgme_data_t pgp_data;
244
fd = (int)TEMP_FAILURE_RETRY(open(filename, O_RDONLY));
250
rc = gpgme_data_new_from_fd(&pgp_data, fd);
251
if(rc != GPG_ERR_NO_ERROR){
252
fprintf(stderr, "bad gpgme_data_new_from_fd: %s: %s\n",
253
gpgme_strsource(rc), gpgme_strerror(rc));
257
rc = gpgme_op_import(mc.ctx, pgp_data);
258
if(rc != GPG_ERR_NO_ERROR){
259
fprintf(stderr, "bad gpgme_op_import: %s: %s\n",
260
gpgme_strsource(rc), gpgme_strerror(rc));
264
ret = (int)TEMP_FAILURE_RETRY(close(fd));
266
perror_plus("close");
268
gpgme_data_release(pgp_data);
273
fprintf(stderr, "Initializing GPGME\n");
107
fprintf(stderr, "Trying to decrypt OpenPGP data\n");
277
111
gpgme_check_version(NULL);
278
112
rc = gpgme_engine_check_version(GPGME_PROTOCOL_OpenPGP);
279
if(rc != GPG_ERR_NO_ERROR){
113
if (rc != GPG_ERR_NO_ERROR){
280
114
fprintf(stderr, "bad gpgme_engine_check_version: %s: %s\n",
281
115
gpgme_strsource(rc), gpgme_strerror(rc));
285
/* Set GPGME home directory for the OpenPGP engine only */
286
rc = gpgme_get_engine_info(&engine_info);
287
if(rc != GPG_ERR_NO_ERROR){
119
/* Set GPGME home directory for the OpenPGP engine only */
120
rc = gpgme_get_engine_info (&engine_info);
121
if (rc != GPG_ERR_NO_ERROR){
288
122
fprintf(stderr, "bad gpgme_get_engine_info: %s: %s\n",
289
123
gpgme_strsource(rc), gpgme_strerror(rc));
292
126
while(engine_info != NULL){
293
127
if(engine_info->protocol == GPGME_PROTOCOL_OpenPGP){
294
128
gpgme_set_engine_info(GPGME_PROTOCOL_OpenPGP,
295
engine_info->file_name, tempdir);
129
engine_info->file_name, homedir);
298
132
engine_info = engine_info->next;
300
134
if(engine_info == NULL){
301
fprintf(stderr, "Could not set GPGME home dir to %s\n", tempdir);
305
/* Create new GPGME "context" */
306
rc = gpgme_new(&(mc.ctx));
307
if(rc != GPG_ERR_NO_ERROR){
308
fprintf(stderr, "bad gpgme_new: %s: %s\n",
309
gpgme_strsource(rc), gpgme_strerror(rc));
313
if(not import_key(pubkey) or not import_key(seckey)){
321
* Decrypt OpenPGP data.
322
* Returns -1 on error
324
static ssize_t pgp_packet_decrypt(const char *cryptotext,
327
gpgme_data_t dh_crypto, dh_plain;
330
size_t plaintext_capacity = 0;
331
ssize_t plaintext_length = 0;
334
fprintf(stderr, "Trying to decrypt OpenPGP data\n");
135
fprintf(stderr, "Could not set GPGME home dir to %s\n", homedir);
337
139
/* Create new GPGME data buffer from memory cryptotext */
338
140
rc = gpgme_data_new_from_mem(&dh_crypto, cryptotext, crypto_size,
340
if(rc != GPG_ERR_NO_ERROR){
142
if (rc != GPG_ERR_NO_ERROR){
341
143
fprintf(stderr, "bad gpgme_data_new_from_mem: %s: %s\n",
342
144
gpgme_strsource(rc), gpgme_strerror(rc));
443
260
return plaintext_length;
446
static const char * safer_gnutls_strerror(int value){
447
const char *ret = gnutls_strerror(value); /* Spurious warning from
448
-Wunreachable-code */
263
static const char * safer_gnutls_strerror (int value) {
264
const char *ret = gnutls_strerror (value);
450
266
ret = "(unknown)";
454
/* GnuTLS log function callback */
455
270
static void debuggnutls(__attribute__((unused)) int level,
456
271
const char* string){
457
fprintf(stderr, "GnuTLS: %s", string);
272
fprintf(stderr, "%s", string);
460
static int init_gnutls_global(const char *pubkeyfilename,
461
const char *seckeyfilename){
275
static int initgnutls(mandos_context *mc, gnutls_session_t *session,
276
gnutls_dh_params_t *dh_params){
465
281
fprintf(stderr, "Initializing GnuTLS\n");
468
ret = gnutls_global_init();
469
if(ret != GNUTLS_E_SUCCESS){
470
fprintf(stderr, "GnuTLS global_init: %s\n",
471
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));
476
/* "Use a log level over 10 to enable all debugging options."
479
291
gnutls_global_set_log_level(11);
480
292
gnutls_global_set_log_function(debuggnutls);
483
/* OpenPGP credentials */
484
ret = gnutls_certificate_allocate_credentials(&mc.cred);
485
if(ret != GNUTLS_E_SUCCESS){
486
fprintf(stderr, "GnuTLS memory error: %s\n",
487
safer_gnutls_strerror(ret));
488
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));
493
fprintf(stderr, "Attempting to use OpenPGP public key %s and"
494
" 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,
498
309
ret = gnutls_certificate_set_openpgp_key_file
499
(mc.cred, pubkeyfilename, seckeyfilename,
500
GNUTLS_OPENPGP_FMT_BASE64);
501
if(ret != GNUTLS_E_SUCCESS){
503
"Error[%d] while reading the OpenPGP key pair ('%s',"
504
" '%s')\n", ret, pubkeyfilename, seckeyfilename);
505
fprintf(stderr, "The GnuTLS error is: %s\n",
506
safer_gnutls_strerror(ret));
510
/* GnuTLS server initialization */
511
ret = gnutls_dh_params_init(&mc.dh_params);
512
if(ret != GNUTLS_E_SUCCESS){
513
fprintf(stderr, "Error in GnuTLS DH parameter initialization:"
514
" %s\n", safer_gnutls_strerror(ret));
517
ret = gnutls_dh_params_generate2(mc.dh_params, mc.dh_bits);
518
if(ret != GNUTLS_E_SUCCESS){
519
fprintf(stderr, "Error in GnuTLS prime generation: %s\n",
520
safer_gnutls_strerror(ret));
524
gnutls_certificate_set_dh_params(mc.cred, mc.dh_params);
530
gnutls_certificate_free_credentials(mc.cred);
531
gnutls_global_deinit();
532
gnutls_dh_params_deinit(mc.dh_params);
536
static int init_gnutls_session(gnutls_session_t *session){
538
/* GnuTLS session creation */
540
ret = gnutls_init(session, GNUTLS_SERVER);
544
} while(ret == GNUTLS_E_INTERRUPTED or ret == GNUTLS_E_AGAIN);
545
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){
546
341
fprintf(stderr, "Error in GnuTLS session initialization: %s\n",
547
342
safer_gnutls_strerror(ret));
553
ret = gnutls_priority_set_direct(*session, mc.priority, &err);
555
gnutls_deinit(*session);
558
} while(ret == GNUTLS_E_INTERRUPTED or ret == GNUTLS_E_AGAIN);
559
if(ret != GNUTLS_E_SUCCESS){
560
fprintf(stderr, "Syntax error at: %s\n", err);
561
fprintf(stderr, "GnuTLS error: %s\n",
562
safer_gnutls_strerror(ret));
563
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));
569
ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,
572
gnutls_deinit(*session);
575
} while(ret == GNUTLS_E_INTERRUPTED or ret == GNUTLS_E_AGAIN);
576
if(ret != GNUTLS_E_SUCCESS){
577
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",
578
357
safer_gnutls_strerror(ret));
579
gnutls_deinit(*session);
583
361
/* ignore client certificate if any. */
584
gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);
362
gnutls_certificate_server_set_request (*session,
586
gnutls_dh_set_prime_bits(*session, mc.dh_bits);
365
gnutls_dh_set_prime_bits (*session, mc->dh_bits);
591
/* Avahi log function callback */
592
370
static void empty_log(__attribute__((unused)) AvahiLogLevel level,
593
371
__attribute__((unused)) const char *txt){}
595
/* Called when a Mandos server is found */
596
373
static int start_mandos_communication(const char *ip, uint16_t port,
597
374
AvahiIfIndex if_index,
599
int ret, tcp_sd = -1;
602
struct sockaddr_in in;
603
struct sockaddr_in6 in6;
377
struct sockaddr_in6 to;
605
378
char *buffer = NULL;
606
char *decrypted_buffer = NULL;
379
char *decrypted_buffer;
607
380
size_t buffer_length = 0;
608
381
size_t buffer_capacity = 0;
382
ssize_t decrypted_buffer_size;
385
char interface[IF_NAMESIZE];
611
386
gnutls_session_t session;
612
int pf; /* Protocol family */
629
fprintf(stderr, "Bad address family: %d\n", af);
634
ret = init_gnutls_session(&session);
640
fprintf(stderr, "Setting up a TCP connection to %s, port %" PRIu16
644
tcp_sd = socket(pf, SOCK_STREAM, 0);
647
perror_plus("socket");
657
memset(&to, 0, sizeof(to));
659
to.in6.sin6_family = (sa_family_t)af;
660
ret = inet_pton(af, ip, &to.in6.sin6_addr);
662
to.in.sin_family = (sa_family_t)af;
663
ret = inet_pton(af, ip, &to.in.sin_addr);
667
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);
673
416
fprintf(stderr, "Bad address: %s\n", ip);
678
to.in6.sin6_port = htons(port); /* Spurious warnings from
680
-Wunreachable-code */
682
if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */
683
(&to.in6.sin6_addr)){ /* -Wstrict-aliasing=2 or lower and
685
if(if_index == AVAHI_IF_UNSPEC){
686
fprintf(stderr, "An IPv6 link-local address is incomplete"
687
" without a network interface\n");
691
/* Set the network interface number as scope */
692
to.in6.sin6_scope_id = (uint32_t)if_index;
695
to.in.sin_port = htons(port); /* Spurious warnings from
697
-Wunreachable-code */
419
to.sin6_port = htons(port); /* Spurious warning */
421
to.sin6_scope_id = (uint32_t)if_index;
706
if(af == AF_INET6 and if_index != AVAHI_IF_UNSPEC){
707
char interface[IF_NAMESIZE];
708
if(if_indextoname((unsigned int)if_index, interface) == NULL){
709
perror_plus("if_indextoname");
711
fprintf(stderr, "Connection to: %s%%%s, port %" PRIu16 "\n",
712
ip, interface, port);
715
fprintf(stderr, "Connection to: %s, port %" PRIu16 "\n", ip,
718
char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?
719
INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";
722
pcret = inet_ntop(af, &(to.in6.sin6_addr), addrstr,
725
pcret = inet_ntop(af, &(to.in.sin_addr), addrstr,
729
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){
731
430
if(strcmp(addrstr, ip) != 0){
732
431
fprintf(stderr, "Canonical address form: %s\n", addrstr);
1063
642
case AVAHI_BROWSER_ALL_FOR_NOW:
1064
643
case AVAHI_BROWSER_CACHE_EXHAUSTED:
1066
fprintf(stderr, "No Mandos server found, still searching...\n");
1072
/* Signal handler that stops main loop after SIGTERM */
1073
static void handle_sigterm(int sig){
1078
signal_received = sig;
1079
int old_errno = errno;
1080
/* set main loop to exit */
1081
if(mc.simple_poll != NULL){
1082
avahi_simple_poll_quit(mc.simple_poll);
1088
* This function determines if a directory entry in /sys/class/net
1089
* corresponds to an acceptable network device.
1090
* (This function is passed to scandir(3) as a filter function.)
1092
int good_interface(const struct dirent *if_entry){
1094
char *flagname = NULL;
1095
if(if_entry->d_name[0] == '.'){
1098
int ret = asprintf(&flagname, "%s/%s/flags", sys_class_net,
1101
perror_plus("asprintf");
1104
int flags_fd = (int)TEMP_FAILURE_RETRY(open(flagname, O_RDONLY));
1106
perror_plus("open");
1111
typedef short ifreq_flags; /* ifreq.ifr_flags in netdevice(7) */
1112
/* read line from flags_fd */
1113
ssize_t to_read = 2+(sizeof(ifreq_flags)*2)+1; /* "0x1003\n" */
1114
char *flagstring = malloc((size_t)to_read+1); /* +1 for final \0 */
1115
flagstring[(size_t)to_read] = '\0';
1116
if(flagstring == NULL){
1117
perror_plus("malloc");
1122
ssret = (ssize_t)TEMP_FAILURE_RETRY(read(flags_fd, flagstring,
1125
perror_plus("read");
1139
tmpmax = strtoimax(flagstring, &tmp, 0);
1140
if(errno != 0 or tmp == flagstring or (*tmp != '\0'
1141
and not (isspace(*tmp)))
1142
or tmpmax != (ifreq_flags)tmpmax){
1144
fprintf(stderr, "Invalid flags \"%s\" for interface \"%s\"\n",
1145
flagstring, if_entry->d_name);
1151
ifreq_flags flags = (ifreq_flags)tmpmax;
1152
/* Reject the loopback device */
1153
if(flags & IFF_LOOPBACK){
1155
fprintf(stderr, "Rejecting loopback interface \"%s\"\n",
1160
/* Accept point-to-point devices only if connect_to is specified */
1161
if(connect_to != NULL and (flags & IFF_POINTOPOINT)){
1163
fprintf(stderr, "Accepting point-to-point interface \"%s\"\n",
1168
/* Otherwise, reject non-broadcast-capable devices */
1169
if(not (flags & IFF_BROADCAST)){
1171
fprintf(stderr, "Rejecting non-broadcast interface \"%s\"\n",
1176
/* Reject non-ARP interfaces (including dummy interfaces) */
1177
if(flags & IFF_NOARP){
1179
fprintf(stderr, "Rejecting non-ARP interface \"%s\"\n",
1184
/* Accept this device */
1186
fprintf(stderr, "Interface \"%s\" is acceptable\n",
1192
int notdotentries(const struct dirent *direntry){
1193
/* Skip "." and ".." */
1194
if(direntry->d_name[0] == '.'
1195
and (direntry->d_name[1] == '\0'
1196
or (direntry->d_name[1] == '.'
1197
and direntry->d_name[2] == '\0'))){
1203
int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval){
1205
struct timespec now;
1206
struct timespec waited_time;
1207
intmax_t block_time;
1210
if(mc.current_server == NULL){
1213
"Wait until first server is found. No timeout!\n");
1215
ret = avahi_simple_poll_iterate(s, -1);
1218
fprintf(stderr, "Check current_server if we should run it,"
1221
/* the current time */
1222
ret = clock_gettime(CLOCK_MONOTONIC, &now);
1224
perror_plus("clock_gettime");
1227
/* Calculating in ms how long time between now and server
1228
who we visted longest time ago. Now - last seen. */
1229
waited_time.tv_sec = (now.tv_sec
1230
- mc.current_server->last_seen.tv_sec);
1231
waited_time.tv_nsec = (now.tv_nsec
1232
- mc.current_server->last_seen.tv_nsec);
1233
/* total time is 10s/10,000ms.
1234
Converting to s from ms by dividing by 1,000,
1235
and ns to ms by dividing by 1,000,000. */
1236
block_time = ((retry_interval
1237
- ((intmax_t)waited_time.tv_sec * 1000))
1238
- ((intmax_t)waited_time.tv_nsec / 1000000));
1241
fprintf(stderr, "Blocking for %ld ms\n", block_time);
1244
if(block_time <= 0){
1245
ret = start_mandos_communication(mc.current_server->ip,
1246
mc.current_server->port,
1247
mc.current_server->if_index,
1248
mc.current_server->af);
1250
avahi_simple_poll_quit(mc.simple_poll);
1253
ret = clock_gettime(CLOCK_MONOTONIC,
1254
&mc.current_server->last_seen);
1256
perror_plus("clock_gettime");
1259
mc.current_server = mc.current_server->next;
1260
block_time = 0; /* Call avahi to find new Mandos
1261
servers, but don't block */
1264
ret = avahi_simple_poll_iterate(s, (int)block_time);
1267
if (ret > 0 or errno != EINTR) {
1268
return (ret != 1) ? ret : 0;
1274
int main(int argc, char *argv[]){
1275
AvahiSServiceBrowser *sb = NULL;
1280
int exitcode = EXIT_SUCCESS;
1281
const char *interface = "";
1282
struct ifreq network;
1284
bool take_down_interface = false;
1287
char tempdir[] = "/tmp/mandosXXXXXX";
1288
bool tempdir_created = false;
1289
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
1290
const char *seckey = PATHDIR "/" SECKEY;
1291
const char *pubkey = PATHDIR "/" PUBKEY;
1293
bool gnutls_initialized = false;
1294
bool gpgme_initialized = false;
1296
double retry_interval = 10; /* 10s between trying a server and
1297
retrying the same server again */
1299
struct sigaction old_sigterm_action = { .sa_handler = SIG_DFL };
1300
struct sigaction sigterm_action = { .sa_handler = handle_sigterm };
1305
/* Lower any group privileges we might have, just to be safe */
1309
perror_plus("setgid");
1312
/* Lower user privileges (temporarily) */
1316
perror_plus("seteuid");
1324
struct argp_option options[] = {
1325
{ .name = "debug", .key = 128,
1326
.doc = "Debug mode", .group = 3 },
1327
{ .name = "connect", .key = 'c',
1328
.arg = "ADDRESS:PORT",
1329
.doc = "Connect directly to a specific Mandos server",
1331
{ .name = "interface", .key = 'i',
1333
.doc = "Network interface that will be used to search for"
1336
{ .name = "seckey", .key = 's',
1338
.doc = "OpenPGP secret key file base name",
1340
{ .name = "pubkey", .key = 'p',
1342
.doc = "OpenPGP public key file base name",
1344
{ .name = "dh-bits", .key = 129,
1346
.doc = "Bit length of the prime number used in the"
1347
" Diffie-Hellman key exchange",
1349
{ .name = "priority", .key = 130,
1351
.doc = "GnuTLS priority string for the TLS handshake",
1353
{ .name = "delay", .key = 131,
1355
.doc = "Maximum delay to wait for interface startup",
1357
{ .name = "retry", .key = 132,
1359
.doc = "Retry interval used when denied by the mandos server",
1362
* These reproduce what we would get without ARGP_NO_HELP
1364
{ .name = "help", .key = '?',
1365
.doc = "Give this help list", .group = -1 },
1366
{ .name = "usage", .key = -3,
1367
.doc = "Give a short usage message", .group = -1 },
1368
{ .name = "version", .key = 'V',
1369
.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"};
1373
error_t parse_opt(int key, char *arg,
1374
struct argp_state *state){
1377
case 128: /* --debug */
1380
case 'c': /* --connect */
1383
case 'i': /* --interface */
1386
case 's': /* --seckey */
1389
case 'p': /* --pubkey */
1392
case 129: /* --dh-bits */
1394
tmpmax = strtoimax(arg, &tmp, 10);
1395
if(errno != 0 or tmp == arg or *tmp != '\0'
1396
or tmpmax != (typeof(mc.dh_bits))tmpmax){
1397
argp_error(state, "Bad number of DH bits");
1399
mc.dh_bits = (typeof(mc.dh_bits))tmpmax;
1401
case 130: /* --priority */
1404
case 131: /* --delay */
1406
delay = strtof(arg, &tmp);
1407
if(errno != 0 or tmp == arg or *tmp != '\0'){
1408
argp_error(state, "Bad delay");
1410
case 132: /* --retry */
1412
retry_interval = strtod(arg, &tmp);
1413
if(errno != 0 or tmp == arg or *tmp != '\0'
1414
or (retry_interval * 1000) > INT_MAX){
1415
argp_error(state, "Bad retry interval");
1419
* These reproduce what we would get without ARGP_NO_HELP
1421
case '?': /* --help */
1422
argp_state_help(state, state->out_stream,
1423
(ARGP_HELP_STD_HELP | ARGP_HELP_EXIT_ERR)
1424
& ~(unsigned int)ARGP_HELP_EXIT_OK);
1425
case -3: /* --usage */
1426
argp_state_help(state, state->out_stream,
1427
ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);
1428
case 'V': /* --version */
1429
fprintf(state->out_stream, "%s\n", argp_program_version);
1430
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;
1433
return ARGP_ERR_UNKNOWN;
1438
struct argp argp = { .options = options, .parser = parse_opt,
1440
.doc = "Mandos client -- Get and decrypt"
1441
" passwords from a Mandos server" };
1442
ret = argp_parse(&argp, argc, argv,
1443
ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);
1450
perror_plus("argp_parse");
1451
exitcode = EX_OSERR;
1454
exitcode = EX_USAGE;
1460
/* Work around Debian bug #633582:
1461
<http://bugs.debian.org/633582> */
1464
/* Re-raise priviliges */
1468
perror_plus("seteuid");
1471
int seckey_fd = open(PATHDIR "/" SECKEY, O_RDONLY);
1472
if(seckey_fd == -1){
1473
perror_plus("open");
1475
ret = (int)TEMP_FAILURE_RETRY(fstat(seckey_fd, &st));
1477
perror_plus("fstat");
1479
if(S_ISREG(st.st_mode) and st.st_uid == 0 and st.st_gid == 0){
1480
ret = fchown(seckey_fd, uid, gid);
1482
perror_plus("fchown");
1486
TEMP_FAILURE_RETRY(close(seckey_fd));
1489
int pubkey_fd = open(PATHDIR "/" PUBKEY, O_RDONLY);
1490
if(pubkey_fd == -1){
1491
perror_plus("open");
1493
ret = (int)TEMP_FAILURE_RETRY(fstat(pubkey_fd, &st));
1495
perror_plus("fstat");
1497
if(S_ISREG(st.st_mode) and st.st_uid == 0 and st.st_gid == 0){
1498
ret = fchown(pubkey_fd, uid, gid);
1500
perror_plus("fchown");
1504
TEMP_FAILURE_RETRY(close(pubkey_fd));
1507
/* Lower privileges */
1511
perror_plus("seteuid");
1516
avahi_set_log_function(empty_log);
1519
if(interface[0] == '\0'){
1520
struct dirent **direntries;
1521
ret = scandir(sys_class_net, &direntries, good_interface,
1524
/* Pick the first good interface */
1525
interface = strdup(direntries[0]->d_name);
1527
fprintf(stderr, "Using interface \"%s\"\n", interface);
1529
if(interface == NULL){
1530
perror_plus("malloc");
1532
exitcode = EXIT_FAILURE;
1538
fprintf(stderr, "Could not find a network interface\n");
1539
exitcode = EXIT_FAILURE;
1544
/* Initialize Avahi early so avahi_simple_poll_quit() can be called
1545
from the signal handler */
1546
/* Initialize the pseudo-RNG for Avahi */
1547
srand((unsigned int) time(NULL));
1548
mc.simple_poll = avahi_simple_poll_new();
1549
if(mc.simple_poll == NULL){
1550
fprintf(stderr, "Avahi: Failed to create simple poll object.\n");
1551
exitcode = EX_UNAVAILABLE;
1555
sigemptyset(&sigterm_action.sa_mask);
1556
ret = sigaddset(&sigterm_action.sa_mask, SIGINT);
1558
perror_plus("sigaddset");
1559
exitcode = EX_OSERR;
1562
ret = sigaddset(&sigterm_action.sa_mask, SIGHUP);
1564
perror_plus("sigaddset");
1565
exitcode = EX_OSERR;
1568
ret = sigaddset(&sigterm_action.sa_mask, SIGTERM);
1570
perror_plus("sigaddset");
1571
exitcode = EX_OSERR;
1574
/* Need to check if the handler is SIG_IGN before handling:
1575
| [[info:libc:Initial Signal Actions]] |
1576
| [[info:libc:Basic Signal Handling]] |
1578
ret = sigaction(SIGINT, NULL, &old_sigterm_action);
1580
perror_plus("sigaction");
1583
if(old_sigterm_action.sa_handler != SIG_IGN){
1584
ret = sigaction(SIGINT, &sigterm_action, NULL);
1586
perror_plus("sigaction");
1587
exitcode = EX_OSERR;
1591
ret = sigaction(SIGHUP, NULL, &old_sigterm_action);
1593
perror_plus("sigaction");
1596
if(old_sigterm_action.sa_handler != SIG_IGN){
1597
ret = sigaction(SIGHUP, &sigterm_action, NULL);
1599
perror_plus("sigaction");
1600
exitcode = EX_OSERR;
1604
ret = sigaction(SIGTERM, NULL, &old_sigterm_action);
1606
perror_plus("sigaction");
1609
if(old_sigterm_action.sa_handler != SIG_IGN){
1610
ret = sigaction(SIGTERM, &sigterm_action, NULL);
1612
perror_plus("sigaction");
1613
exitcode = EX_OSERR;
1618
/* If the interface is down, bring it up */
1619
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");
1620
754
if_index = (AvahiIfIndex) if_nametoindex(interface);
1621
755
if(if_index == 0){
1622
756
fprintf(stderr, "No such interface: \"%s\"\n", interface);
1623
exitcode = EX_UNAVAILABLE;
1631
/* Re-raise priviliges */
1635
perror_plus("seteuid");
1639
/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO
1640
messages about the network interface to mess up the prompt */
1641
ret = klogctl(8, NULL, 5);
1642
bool restore_loglevel = true;
1644
restore_loglevel = false;
1645
perror_plus("klogctl");
1647
#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);
1649
784
sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1651
perror_plus("socket");
1652
exitcode = EX_OSERR;
1654
if(restore_loglevel){
1655
ret = klogctl(7, NULL, 0);
1657
perror_plus("klogctl");
1660
#endif /* __linux__ */
1661
/* Lower privileges */
1665
perror_plus("seteuid");
787
returncode = EXIT_FAILURE;
1669
strcpy(network.ifr_name, interface);
790
strcpy(network.ifr_name, interface); /* Spurious warning */
1670
791
ret = ioctl(sd, SIOCGIFFLAGS, &network);
1672
perror_plus("ioctl SIOCGIFFLAGS");
1674
if(restore_loglevel){
1675
ret = klogctl(7, NULL, 0);
1677
perror_plus("klogctl");
1680
#endif /* __linux__ */
1681
exitcode = EX_OSERR;
1682
/* Lower privileges */
1686
perror_plus("seteuid");
794
perror("ioctl SIOCGIFFLAGS");
795
returncode = EXIT_FAILURE;
1690
798
if((network.ifr_flags & IFF_UP) == 0){
1691
799
network.ifr_flags |= IFF_UP;
1692
take_down_interface = true;
1693
800
ret = ioctl(sd, SIOCSIFFLAGS, &network);
1695
take_down_interface = false;
1696
perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");
1697
exitcode = EX_OSERR;
1699
if(restore_loglevel){
1700
ret = klogctl(7, NULL, 0);
1702
perror_plus("klogctl");
1705
#endif /* __linux__ */
1706
/* Lower privileges */
1710
perror_plus("seteuid");
1715
/* Sleep checking until interface is running.
1716
Check every 0.25s, up to total time of delay */
1717
for(int i=0; i < delay * 4; i++){
1718
ret = ioctl(sd, SIOCGIFFLAGS, &network);
1720
perror_plus("ioctl SIOCGIFFLAGS");
1721
} else if(network.ifr_flags & IFF_RUNNING){
1724
struct timespec sleeptime = { .tv_nsec = 250000000 };
1725
ret = nanosleep(&sleeptime, NULL);
1726
if(ret == -1 and errno != EINTR){
1727
perror_plus("nanosleep");
1730
if(not take_down_interface){
1731
/* We won't need the socket anymore */
1732
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1734
perror_plus("close");
1738
if(restore_loglevel){
1739
/* Restores kernel loglevel to default */
1740
ret = klogctl(7, NULL, 0);
1742
perror_plus("klogctl");
1745
#endif /* __linux__ */
1746
/* Lower privileges */
1748
if(take_down_interface){
1749
/* Lower privileges */
1752
perror_plus("seteuid");
1755
/* Lower privileges permanently */
1758
perror_plus("setuid");
1767
ret = init_gnutls_global(pubkey, seckey);
1769
fprintf(stderr, "init_gnutls_global failed\n");
1770
exitcode = EX_UNAVAILABLE;
1773
gnutls_initialized = true;
1780
if(mkdtemp(tempdir) == NULL){
1781
perror_plus("mkdtemp");
1784
tempdir_created = true;
1790
if(not init_gpgme(pubkey, seckey, tempdir)){
1791
fprintf(stderr, "init_gpgme failed\n");
1792
exitcode = EX_UNAVAILABLE;
1795
gpgme_initialized = true;
1802
if(connect_to != NULL){
1803
/* Connect directly, do not use Zeroconf */
1804
/* (Mainly meant for debugging) */
1805
char *address = strrchr(connect_to, ':');
1806
if(address == NULL){
1807
fprintf(stderr, "No colon in address\n");
1808
exitcode = EX_USAGE;
1818
tmpmax = strtoimax(address+1, &tmp, 10);
1819
if(errno != 0 or tmp == address+1 or *tmp != '\0'
1820
or tmpmax != (uint16_t)tmpmax){
1821
fprintf(stderr, "Bad port number\n");
1822
exitcode = EX_USAGE;
1830
port = (uint16_t)tmpmax;
1832
address = connect_to;
1833
/* Colon in address indicates IPv6 */
1835
if(strchr(address, ':') != NULL){
1845
while(not quit_now){
1846
ret = start_mandos_communication(address, port, if_index, af);
1847
if(quit_now or ret == 0){
1850
sleep((int)retry_interval or 1);
1854
exitcode = EXIT_SUCCESS;
1865
AvahiServerConfig config;
1866
/* 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 */
1867
824
avahi_server_config_init(&config);
1868
825
config.publish_hinfo = 0;
1869
826
config.publish_addresses = 0;
1870
827
config.publish_workstation = 0;
1871
828
config.publish_domain = 0;
1873
830
/* Allocate a new server */
1874
mc.server = avahi_server_new(avahi_simple_poll_get
1875
(mc.simple_poll), &config, NULL,
831
mc.server=avahi_server_new(avahi_simple_poll_get(mc.simple_poll),
832
&config, NULL, NULL, &error);
1878
/* Free the Avahi configuration data */
834
/* Free the configuration data */
1879
835
avahi_server_config_free(&config);
1882
/* Check if creating the Avahi server object succeeded */
1883
if(mc.server == NULL){
1884
fprintf(stderr, "Failed to create Avahi server: %s\n",
1885
avahi_strerror(error));
1886
exitcode = EX_UNAVAILABLE;
1894
/* Create the Avahi service browser */
1895
sb = avahi_s_service_browser_new(mc.server, if_index,
1896
AVAHI_PROTO_UNSPEC, "_mandos._tcp",
1897
NULL, 0, browse_callback, NULL);
1899
fprintf(stderr, "Failed to create service browser: %s\n",
1900
avahi_strerror(avahi_server_errno(mc.server)));
1901
exitcode = EX_UNAVAILABLE;
1909
/* Run the main loop */
1912
fprintf(stderr, "Starting Avahi loop search\n");
1915
ret = avahi_loop_with_timeout(mc.simple_poll,
1916
(int)(retry_interval * 1000));
1918
fprintf(stderr, "avahi_loop_with_timeout exited %s\n",
1919
(ret == 0) ? "successfully" : "with error");
1925
fprintf(stderr, "%s exiting\n", argv[0]);
1928
/* Cleanup things */
1930
avahi_s_service_browser_free(sb);
1932
if(mc.server != NULL)
1933
avahi_server_free(mc.server);
1935
if(mc.simple_poll != NULL)
1936
avahi_simple_poll_free(mc.simple_poll);
1938
if(gnutls_initialized){
1939
gnutls_certificate_free_credentials(mc.cred);
1940
gnutls_global_deinit();
1941
gnutls_dh_params_deinit(mc.dh_params);
1944
if(gpgme_initialized){
1945
gpgme_release(mc.ctx);
1948
/* Cleans up the circular linked list of Mandos servers the client
1950
if(mc.current_server != NULL){
1951
mc.current_server->prev->next = NULL;
1952
while(mc.current_server != NULL){
1953
server *next = mc.current_server->next;
1954
free(mc.current_server);
1955
mc.current_server = next;
1959
/* Take down the network interface */
1960
if(take_down_interface){
1961
/* Re-raise priviliges */
1965
perror_plus("seteuid");
1968
ret = ioctl(sd, SIOCGIFFLAGS, &network);
1970
perror_plus("ioctl SIOCGIFFLAGS");
1971
} else if(network.ifr_flags & IFF_UP) {
1972
network.ifr_flags &= ~(short)IFF_UP; /* clear flag */
1973
ret = ioctl(sd, SIOCSIFFLAGS, &network);
1975
perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");
1978
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1980
perror_plus("close");
1982
/* Lower privileges permanently */
1986
perror_plus("setuid");
1991
/* Removes the GPGME temp directory and all files inside */
1992
if(tempdir_created){
1993
struct dirent **direntries = NULL;
1994
struct dirent *direntry = NULL;
1995
ret = scandir(tempdir, &direntries, notdotentries, alphasort);
1997
for(int i = 0; i < ret; i++){
1998
direntry = direntries[i];
1999
char *fullname = NULL;
2000
ret = asprintf(&fullname, "%s/%s", tempdir,
2003
perror_plus("asprintf");
2006
ret = remove(fullname);
2008
fprintf(stderr, "remove(\"%s\"): %s\n", fullname,
2015
/* need to be cleaned even if ret == 0 because man page doesn't
2019
perror_plus("scandir");
2021
ret = rmdir(tempdir);
2022
if(ret == -1 and errno != ENOENT){
2023
perror_plus("rmdir");
2028
sigemptyset(&old_sigterm_action.sa_mask);
2029
old_sigterm_action.sa_handler = SIG_DFL;
2030
ret = (int)TEMP_FAILURE_RETRY(sigaction(signal_received,
2031
&old_sigterm_action,
2034
perror_plus("sigaction");
2037
ret = raise(signal_received);
2038
} while(ret != 0 and errno == EINTR);
2040
perror_plus("raise");
2043
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);