107
46
#include <avahi-common/malloc.h>
108
47
#include <avahi-common/error.h>
111
#include <gnutls/gnutls.h> /* All GnuTLS types, constants and
114
init_gnutls_session(),
116
#include <gnutls/openpgp.h>
117
/* gnutls_certificate_set_openpgp_key_file(),
118
GNUTLS_OPENPGP_FMT_BASE64 */
121
#include <gpgme.h> /* All GPGME types, constants and
124
GPGME_PROTOCOL_OpenPGP,
50
#include <sys/types.h> /* socket(), setsockopt(), inet_pton() */
51
#include <sys/socket.h> /* socket(), setsockopt(), struct sockaddr_in6, struct in6_addr, inet_pton() */
52
#include <gnutls/gnutls.h> /* ALL GNUTLS STUFF */
53
#include <gnutls/openpgp.h> /* gnutls with openpgp stuff */
55
#include <unistd.h> /* close() */
56
#include <netinet/in.h>
57
#include <stdbool.h> /* true */
58
#include <string.h> /* memset */
59
#include <arpa/inet.h> /* inet_pton() */
60
#include <iso646.h> /* not */
63
#include <errno.h> /* perror() */
68
#define CERT_ROOT "/conf/conf.d/cryptkeyreq/"
70
#define CERTFILE CERT_ROOT "openpgp-client.txt"
71
#define KEYFILE CERT_ROOT "openpgp-client-key.txt"
127
72
#define BUFFER_SIZE 256
129
#define PATHDIR "/conf/conf.d/mandos"
130
#define SECKEY "seckey.txt"
131
#define PUBKEY "pubkey.txt"
132
#define HOOKDIR "/lib/mandos/network-hooks.d"
135
static const char mandos_protocol_version[] = "1";
136
const char *argp_program_version = "mandos-client " VERSION;
137
const char *argp_program_bug_address = "<mandos@recompile.se>";
138
static const char sys_class_net[] = "/sys/class/net";
139
char *connect_to = NULL;
140
const char *hookdir = HOOKDIR;
144
/* Doubly linked list that need to be circularly linked when used */
145
typedef struct server{
148
AvahiIfIndex if_index;
150
struct timespec last_seen;
155
/* Used for passing in values through the Avahi callback functions */
76
gnutls_session_t session;
158
77
gnutls_certificate_credentials_t cred;
159
unsigned int dh_bits;
160
78
gnutls_dh_params_t dh_params;
161
const char *priority;
82
ssize_t gpg_packet_decrypt (char *packet, size_t packet_size, char **new_packet, char *homedir){
83
gpgme_data_t dh_crypto, dh_plain;
163
server *current_server;
165
size_t interfaces_size;
168
/* global so signal handler can reach it*/
169
AvahiSimplePoll *simple_poll;
171
sig_atomic_t quit_now = 0;
172
int signal_received = 0;
174
/* Function to use when printing errors */
175
void perror_plus(const char *print_text){
177
fprintf(stderr, "Mandos plugin %s: ",
178
program_invocation_short_name);
183
__attribute__((format (gnu_printf, 2, 3)))
184
int fprintf_plus(FILE *stream, const char *format, ...){
186
va_start (ap, format);
188
TEMP_FAILURE_RETRY(fprintf(stream, "Mandos plugin %s: ",
189
program_invocation_short_name));
190
return TEMP_FAILURE_RETRY(vfprintf(stream, format, ap));
194
* Make additional room in "buffer" for at least BUFFER_SIZE more
195
* bytes. "buffer_capacity" is how much is currently allocated,
196
* "buffer_length" is how much is already used.
198
size_t incbuffer(char **buffer, size_t buffer_length,
199
size_t buffer_capacity){
200
if(buffer_length + BUFFER_SIZE > buffer_capacity){
201
*buffer = realloc(*buffer, buffer_capacity + BUFFER_SIZE);
205
buffer_capacity += BUFFER_SIZE;
207
return buffer_capacity;
210
/* Add server to set of servers to retry periodically */
211
bool add_server(const char *ip, in_port_t port, AvahiIfIndex if_index,
212
int af, server **current_server){
214
server *new_server = malloc(sizeof(server));
215
if(new_server == NULL){
216
perror_plus("malloc");
219
*new_server = (server){ .ip = strdup(ip),
221
.if_index = if_index,
223
if(new_server->ip == NULL){
224
perror_plus("strdup");
227
/* Special case of first server */
228
if(*current_server == NULL){
229
new_server->next = new_server;
230
new_server->prev = new_server;
231
*current_server = new_server;
232
/* Place the new server last in the list */
234
new_server->next = *current_server;
235
new_server->prev = (*current_server)->prev;
236
new_server->prev->next = new_server;
237
(*current_server)->prev = new_server;
239
ret = clock_gettime(CLOCK_MONOTONIC, &(*current_server)->last_seen);
241
perror_plus("clock_gettime");
250
static bool init_gpgme(const char *seckey, const char *pubkey,
251
const char *tempdir, mandos_context *mc){
87
size_t new_packet_capacity = 0;
88
size_t new_packet_length = 0;
253
89
gpgme_engine_info_t engine_info;
256
* Helper function to insert pub and seckey to the engine keyring.
258
bool import_key(const char *filename){
261
gpgme_data_t pgp_data;
263
fd = (int)TEMP_FAILURE_RETRY(open(filename, O_RDONLY));
269
rc = gpgme_data_new_from_fd(&pgp_data, fd);
270
if(rc != GPG_ERR_NO_ERROR){
271
fprintf_plus(stderr, "bad gpgme_data_new_from_fd: %s: %s\n",
272
gpgme_strsource(rc), gpgme_strerror(rc));
276
rc = gpgme_op_import(mc->ctx, pgp_data);
277
if(rc != GPG_ERR_NO_ERROR){
278
fprintf_plus(stderr, "bad gpgme_op_import: %s: %s\n",
279
gpgme_strsource(rc), gpgme_strerror(rc));
283
ret = (int)TEMP_FAILURE_RETRY(close(fd));
285
perror_plus("close");
287
gpgme_data_release(pgp_data);
292
fprintf_plus(stderr, "Initializing GPGME\n");
296
92
gpgme_check_version(NULL);
297
rc = gpgme_engine_check_version(GPGME_PROTOCOL_OpenPGP);
298
if(rc != GPG_ERR_NO_ERROR){
299
fprintf_plus(stderr, "bad gpgme_engine_check_version: %s: %s\n",
300
gpgme_strsource(rc), gpgme_strerror(rc));
93
gpgme_engine_check_version(GPGME_PROTOCOL_OpenPGP);
304
/* Set GPGME home directory for the OpenPGP engine only */
305
rc = gpgme_get_engine_info(&engine_info);
306
if(rc != GPG_ERR_NO_ERROR){
307
fprintf_plus(stderr, "bad gpgme_get_engine_info: %s: %s\n",
308
gpgme_strsource(rc), gpgme_strerror(rc));
95
/* Set GPGME home directory */
96
rc = gpgme_get_engine_info (&engine_info);
97
if (rc != GPG_ERR_NO_ERROR){
98
fprintf(stderr, "bad gpgme_get_engine_info: %s: %s\n",
99
gpgme_strsource(rc), gpgme_strerror(rc));
311
102
while(engine_info != NULL){
312
103
if(engine_info->protocol == GPGME_PROTOCOL_OpenPGP){
313
104
gpgme_set_engine_info(GPGME_PROTOCOL_OpenPGP,
314
engine_info->file_name, tempdir);
105
engine_info->file_name, homedir);
317
108
engine_info = engine_info->next;
319
110
if(engine_info == NULL){
320
fprintf_plus(stderr, "Could not set GPGME home dir to %s\n",
325
/* Create new GPGME "context" */
326
rc = gpgme_new(&(mc->ctx));
327
if(rc != GPG_ERR_NO_ERROR){
328
fprintf_plus(stderr, "Mandos plugin mandos-client: "
329
"bad gpgme_new: %s: %s\n", gpgme_strsource(rc),
334
if(not import_key(pubkey) or not import_key(seckey)){
342
* Decrypt OpenPGP data.
343
* Returns -1 on error
345
static ssize_t pgp_packet_decrypt(const char *cryptotext,
349
gpgme_data_t dh_crypto, dh_plain;
352
size_t plaintext_capacity = 0;
353
ssize_t plaintext_length = 0;
356
fprintf_plus(stderr, "Trying to decrypt OpenPGP data\n");
359
/* Create new GPGME data buffer from memory cryptotext */
360
rc = gpgme_data_new_from_mem(&dh_crypto, cryptotext, crypto_size,
362
if(rc != GPG_ERR_NO_ERROR){
363
fprintf_plus(stderr, "bad gpgme_data_new_from_mem: %s: %s\n",
364
gpgme_strsource(rc), gpgme_strerror(rc));
111
fprintf(stderr, "Could not set home dir to %s\n", homedir);
115
/* Create new GPGME data buffer from packet buffer */
116
rc = gpgme_data_new_from_mem(&dh_crypto, packet, packet_size, 0);
117
if (rc != GPG_ERR_NO_ERROR){
118
fprintf(stderr, "bad gpgme_data_new_from_mem: %s: %s\n",
119
gpgme_strsource(rc), gpgme_strerror(rc));
368
123
/* Create new empty GPGME data buffer for the plaintext */
369
124
rc = gpgme_data_new(&dh_plain);
370
if(rc != GPG_ERR_NO_ERROR){
371
fprintf_plus(stderr, "Mandos plugin mandos-client: "
372
"bad gpgme_data_new: %s: %s\n",
373
gpgme_strsource(rc), gpgme_strerror(rc));
374
gpgme_data_release(dh_crypto);
378
/* Decrypt data from the cryptotext data buffer to the plaintext
380
rc = gpgme_op_decrypt(mc->ctx, dh_crypto, dh_plain);
381
if(rc != GPG_ERR_NO_ERROR){
382
fprintf_plus(stderr, "bad gpgme_op_decrypt: %s: %s\n",
383
gpgme_strsource(rc), gpgme_strerror(rc));
384
plaintext_length = -1;
386
gpgme_decrypt_result_t result;
387
result = gpgme_op_decrypt_result(mc->ctx);
389
fprintf_plus(stderr, "gpgme_op_decrypt_result failed\n");
391
fprintf_plus(stderr, "Unsupported algorithm: %s\n",
392
result->unsupported_algorithm);
393
fprintf_plus(stderr, "Wrong key usage: %u\n",
394
result->wrong_key_usage);
395
if(result->file_name != NULL){
396
fprintf_plus(stderr, "File name: %s\n", result->file_name);
398
gpgme_recipient_t recipient;
399
recipient = result->recipients;
400
while(recipient != NULL){
401
fprintf_plus(stderr, "Public key algorithm: %s\n",
402
gpgme_pubkey_algo_name
403
(recipient->pubkey_algo));
404
fprintf_plus(stderr, "Key ID: %s\n", recipient->keyid);
405
fprintf_plus(stderr, "Secret key available: %s\n",
406
recipient->status == GPG_ERR_NO_SECKEY
408
recipient = recipient->next;
416
fprintf_plus(stderr, "Decryption of OpenPGP data succeeded\n");
125
if (rc != GPG_ERR_NO_ERROR){
126
fprintf(stderr, "bad gpgme_data_new: %s: %s\n",
127
gpgme_strsource(rc), gpgme_strerror(rc));
131
/* Create new GPGME "context" */
132
rc = gpgme_new(&ctx);
133
if (rc != GPG_ERR_NO_ERROR){
134
fprintf(stderr, "bad gpgme_new: %s: %s\n",
135
gpgme_strsource(rc), gpgme_strerror(rc));
139
/* Decrypt data from the FILE pointer to the plaintext data buffer */
140
rc = gpgme_op_decrypt(ctx, dh_crypto, dh_plain);
141
if (rc != GPG_ERR_NO_ERROR){
142
fprintf(stderr, "bad gpgme_op_decrypt: %s: %s\n",
143
gpgme_strsource(rc), gpgme_strerror(rc));
147
/* gpgme_decrypt_result_t result; */
148
/* result = gpgme_op_decrypt_result(ctx); */
149
/* fprintf(stderr, "Unsupported algorithm: %s\n", result->unsupported_algorithm); */
150
/* fprintf(stderr, "Wrong key usage: %d\n", result->wrong_key_usage); */
151
/* if(result->file_name != NULL){ */
152
/* fprintf(stderr, "File name: %s\n", result->file_name); */
154
/* gpgme_recipient_t recipient; */
155
/* recipient = result->recipients; */
157
/* while(recipient != NULL){ */
158
/* fprintf(stderr, "Public key algorithm: %s\n", */
159
/* gpgme_pubkey_algo_name(recipient->pubkey_algo)); */
160
/* fprintf(stderr, "Key ID: %s\n", recipient->keyid); */
161
/* fprintf(stderr, "Secret key available: %s\n", */
162
/* recipient->status == GPG_ERR_NO_SECKEY ? "No" : "Yes"); */
163
/* recipient = recipient->next; */
167
/* Delete the GPGME FILE pointer cryptotext data buffer */
168
gpgme_data_release(dh_crypto);
419
170
/* Seek back to the beginning of the GPGME plaintext data buffer */
420
if(gpgme_data_seek(dh_plain, (off_t)0, SEEK_SET) == -1){
421
perror_plus("gpgme_data_seek");
422
plaintext_length = -1;
171
gpgme_data_seek(dh_plain, 0, SEEK_SET);
428
plaintext_capacity = incbuffer(plaintext,
429
(size_t)plaintext_length,
431
if(plaintext_capacity == 0){
432
perror_plus("incbuffer");
433
plaintext_length = -1;
175
if (new_packet_length + BUFFER_SIZE > new_packet_capacity){
176
*new_packet = realloc(*new_packet, new_packet_capacity + BUFFER_SIZE);
177
if (*new_packet == NULL){
181
new_packet_capacity += BUFFER_SIZE;
437
ret = gpgme_data_read(dh_plain, *plaintext + plaintext_length,
184
ret = gpgme_data_read(dh_plain, *new_packet + new_packet_length, BUFFER_SIZE);
439
185
/* Print the data, if any */
187
/* If password is empty, then a incorrect error will be printed */
445
perror_plus("gpgme_data_read");
446
plaintext_length = -1;
449
plaintext_length += ret;
453
fprintf_plus(stderr, "Decrypted password is: ");
454
for(ssize_t i = 0; i < plaintext_length; i++){
455
fprintf(stderr, "%02hhX ", (*plaintext)[i]);
457
fprintf(stderr, "\n");
462
/* Delete the GPGME cryptotext data buffer */
463
gpgme_data_release(dh_crypto);
465
/* Delete the GPGME plaintext data buffer */
191
perror("gpgme_data_read");
194
new_packet_length += ret;
197
/* Delete the GPGME plaintext data buffer */
466
198
gpgme_data_release(dh_plain);
467
return plaintext_length;
199
return new_packet_length;
470
static const char * safer_gnutls_strerror(int value){
471
const char *ret = gnutls_strerror(value);
202
static const char * safer_gnutls_strerror (int value) {
203
const char *ret = gnutls_strerror (value);
473
205
ret = "(unknown)";
477
/* GnuTLS log function callback */
478
static void debuggnutls(__attribute__((unused)) int level,
480
fprintf_plus(stderr, "GnuTLS: %s", string);
209
void debuggnutls(int level, const char* string){
210
fprintf(stderr, "%s", string);
483
static int init_gnutls_global(const char *pubkeyfilename,
484
const char *seckeyfilename,
213
int initgnutls(encrypted_session *es){
489
fprintf_plus(stderr, "Initializing GnuTLS\n");
492
ret = gnutls_global_init();
493
if(ret != GNUTLS_E_SUCCESS){
494
fprintf_plus(stderr, "GnuTLS global_init: %s\n",
495
safer_gnutls_strerror(ret));
500
/* "Use a log level over 10 to enable all debugging options."
503
gnutls_global_set_log_level(11);
504
gnutls_global_set_log_function(debuggnutls);
507
/* OpenPGP credentials */
508
ret = gnutls_certificate_allocate_credentials(&mc->cred);
509
if(ret != GNUTLS_E_SUCCESS){
510
fprintf_plus(stderr, "GnuTLS memory error: %s\n",
511
safer_gnutls_strerror(ret));
512
gnutls_global_deinit();
517
fprintf_plus(stderr, "Attempting to use OpenPGP public key %s and"
518
" secret key %s as GnuTLS credentials\n",
217
if ((ret = gnutls_global_init ())
218
!= GNUTLS_E_SUCCESS) {
219
fprintf (stderr, "global_init: %s\n", safer_gnutls_strerror(ret));
223
/* Uncomment to enable full debuggin on the gnutls library */
224
/* gnutls_global_set_log_level(11); */
225
/* gnutls_global_set_log_function(debuggnutls); */
228
/* openpgp credentials */
229
if ((ret = gnutls_certificate_allocate_credentials (&es->cred))
230
!= GNUTLS_E_SUCCESS) {
231
fprintf (stderr, "memory error: %s\n", safer_gnutls_strerror(ret));
523
235
ret = gnutls_certificate_set_openpgp_key_file
524
(mc->cred, pubkeyfilename, seckeyfilename,
525
GNUTLS_OPENPGP_FMT_BASE64);
526
if(ret != GNUTLS_E_SUCCESS){
528
"Error[%d] while reading the OpenPGP key pair ('%s',"
529
" '%s')\n", ret, pubkeyfilename, seckeyfilename);
530
fprintf_plus(stderr, "The GnuTLS error is: %s\n",
531
safer_gnutls_strerror(ret));
535
/* GnuTLS server initialization */
536
ret = gnutls_dh_params_init(&mc->dh_params);
537
if(ret != GNUTLS_E_SUCCESS){
538
fprintf_plus(stderr, "Error in GnuTLS DH parameter"
539
" initialization: %s\n",
540
safer_gnutls_strerror(ret));
543
ret = gnutls_dh_params_generate2(mc->dh_params, mc->dh_bits);
544
if(ret != GNUTLS_E_SUCCESS){
545
fprintf_plus(stderr, "Error in GnuTLS prime generation: %s\n",
546
safer_gnutls_strerror(ret));
550
gnutls_certificate_set_dh_params(mc->cred, mc->dh_params);
556
gnutls_certificate_free_credentials(mc->cred);
557
gnutls_global_deinit();
558
gnutls_dh_params_deinit(mc->dh_params);
562
static int init_gnutls_session(gnutls_session_t *session,
565
/* GnuTLS session creation */
567
ret = gnutls_init(session, GNUTLS_SERVER);
571
} while(ret == GNUTLS_E_INTERRUPTED or ret == GNUTLS_E_AGAIN);
572
if(ret != GNUTLS_E_SUCCESS){
574
"Error in GnuTLS session initialization: %s\n",
575
safer_gnutls_strerror(ret));
581
ret = gnutls_priority_set_direct(*session, mc->priority, &err);
583
gnutls_deinit(*session);
586
} while(ret == GNUTLS_E_INTERRUPTED or ret == GNUTLS_E_AGAIN);
587
if(ret != GNUTLS_E_SUCCESS){
588
fprintf_plus(stderr, "Syntax error at: %s\n", err);
589
fprintf_plus(stderr, "GnuTLS error: %s\n",
590
safer_gnutls_strerror(ret));
591
gnutls_deinit(*session);
597
ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,
600
gnutls_deinit(*session);
603
} while(ret == GNUTLS_E_INTERRUPTED or ret == GNUTLS_E_AGAIN);
604
if(ret != GNUTLS_E_SUCCESS){
605
fprintf_plus(stderr, "Error setting GnuTLS credentials: %s\n",
606
safer_gnutls_strerror(ret));
607
gnutls_deinit(*session);
236
(es->cred, CERTFILE, KEYFILE, GNUTLS_OPENPGP_FMT_BASE64);
237
if (ret != GNUTLS_E_SUCCESS) {
239
(stderr, "Error[%d] while reading the OpenPGP key pair ('%s', '%s')\n",
240
ret, CERTFILE, KEYFILE);
241
fprintf(stdout, "The Error is: %s\n",
242
safer_gnutls_strerror(ret));
246
//Gnutls server initialization
247
if ((ret = gnutls_dh_params_init (&es->dh_params))
248
!= GNUTLS_E_SUCCESS) {
249
fprintf (stderr, "Error in dh parameter initialization: %s\n",
250
safer_gnutls_strerror(ret));
254
if ((ret = gnutls_dh_params_generate2 (es->dh_params, DH_BITS))
255
!= GNUTLS_E_SUCCESS) {
256
fprintf (stderr, "Error in prime generation: %s\n",
257
safer_gnutls_strerror(ret));
261
gnutls_certificate_set_dh_params (es->cred, es->dh_params);
263
// Gnutls session creation
264
if ((ret = gnutls_init (&es->session, GNUTLS_SERVER))
265
!= GNUTLS_E_SUCCESS){
266
fprintf(stderr, "Error in gnutls session initialization: %s\n",
267
safer_gnutls_strerror(ret));
270
if ((ret = gnutls_priority_set_direct (es->session, "NORMAL", &err))
271
!= GNUTLS_E_SUCCESS) {
272
fprintf(stderr, "Syntax error at: %s\n", err);
273
fprintf(stderr, "Gnutls error: %s\n",
274
safer_gnutls_strerror(ret));
278
if ((ret = gnutls_credentials_set
279
(es->session, GNUTLS_CRD_CERTIFICATE, es->cred))
280
!= GNUTLS_E_SUCCESS) {
281
fprintf(stderr, "Error setting a credentials set: %s\n",
282
safer_gnutls_strerror(ret));
611
286
/* ignore client certificate if any. */
612
gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);
287
gnutls_certificate_server_set_request (es->session, GNUTLS_CERT_IGNORE);
614
gnutls_dh_set_prime_bits(*session, mc->dh_bits);
289
gnutls_dh_set_prime_bits (es->session, DH_BITS);
619
/* Avahi log function callback */
620
static void empty_log(__attribute__((unused)) AvahiLogLevel level,
621
__attribute__((unused)) const char *txt){}
294
void empty_log(AvahiLogLevel level, const char *txt){}
623
/* Called when a Mandos server is found */
624
static int start_mandos_communication(const char *ip, in_port_t port,
625
AvahiIfIndex if_index,
626
int af, mandos_context *mc){
627
int ret, tcp_sd = -1;
630
struct sockaddr_in in;
631
struct sockaddr_in6 in6;
296
int start_mandos_communcation(char *ip, uint16_t port){
298
struct sockaddr_in6 to;
299
struct in6_addr ip_addr;
300
encrypted_session es;
633
301
char *buffer = NULL;
634
char *decrypted_buffer = NULL;
302
char *decrypted_buffer;
635
303
size_t buffer_length = 0;
636
304
size_t buffer_capacity = 0;
639
gnutls_session_t session;
640
int pf; /* Protocol family */
657
fprintf_plus(stderr, "Bad address family: %d\n", af);
662
if(if_index != AVAHI_IF_UNSPEC and mc->interfaces != NULL){
663
/* Check if the interface is one of the interfaces we are using */
666
char *interface = NULL;
667
while((interface=argz_next(mc->interfaces, mc->interfaces_size,
669
if(if_nametoindex(interface) == (unsigned int)if_index){
677
char interface[IF_NAMESIZE];
678
if(if_indextoname((unsigned int)if_index, interface) == NULL){
679
perror_plus("if_indextoname");
681
fprintf_plus(stderr, "Skipping server on non-used interface"
683
if_indextoname((unsigned int)if_index,
691
ret = init_gnutls_session(&session, mc);
697
fprintf_plus(stderr, "Setting up a TCP connection to %s, port %"
698
PRIuMAX "\n", ip, (uintmax_t)port);
701
tcp_sd = socket(pf, SOCK_STREAM, 0);
704
perror_plus("socket");
714
memset(&to, 0, sizeof(to));
716
to.in6.sin6_family = (sa_family_t)af;
717
ret = inet_pton(af, ip, &to.in6.sin6_addr);
719
to.in.sin_family = (sa_family_t)af;
720
ret = inet_pton(af, ip, &to.in.sin_addr);
724
perror_plus("inet_pton");
305
ssize_t decrypted_buffer_size;
309
tcp_sd = socket(PF_INET6, SOCK_STREAM, 0);
315
ret = setsockopt(tcp_sd, SOL_SOCKET, SO_BINDTODEVICE, "eth0", 5);
317
perror("setsockopt bindtodevice");
321
memset(&to,0,sizeof(to));
322
to.sin6_family = AF_INET6;
323
ret = inet_pton(AF_INET6, ip, &ip_addr);
730
fprintf_plus(stderr, "Bad address: %s\n", ip);
735
to.in6.sin6_port = htons(port);
736
if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */
737
(&to.in6.sin6_addr)){ /* -Wstrict-aliasing=2 or lower and
739
if(if_index == AVAHI_IF_UNSPEC){
740
fprintf_plus(stderr, "An IPv6 link-local address is"
741
" incomplete without a network interface\n");
745
/* Set the network interface number as scope */
746
to.in6.sin6_scope_id = (uint32_t)if_index;
749
to.in.sin_port = htons(port); /* Spurious warnings from
751
-Wunreachable-code */
760
if(af == AF_INET6 and if_index != AVAHI_IF_UNSPEC){
761
char interface[IF_NAMESIZE];
762
if(if_indextoname((unsigned int)if_index, interface) == NULL){
763
perror_plus("if_indextoname");
765
fprintf_plus(stderr, "Connection to: %s%%%s, port %" PRIuMAX
766
"\n", ip, interface, (uintmax_t)port);
769
fprintf_plus(stderr, "Connection to: %s, port %" PRIuMAX "\n",
770
ip, (uintmax_t)port);
772
char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?
773
INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";
776
pcret = inet_ntop(af, &(to.in6.sin6_addr), addrstr,
779
pcret = inet_ntop(af, &(to.in.sin_addr), addrstr,
783
perror_plus("inet_ntop");
785
if(strcmp(addrstr, ip) != 0){
786
fprintf_plus(stderr, "Canonical address form: %s\n", addrstr);
797
ret = connect(tcp_sd, &to.in6, sizeof(to));
799
ret = connect(tcp_sd, &to.in, sizeof(to)); /* IPv4 */
802
if ((errno != ECONNREFUSED and errno != ENETUNREACH) or debug){
804
perror_plus("connect");
815
const char *out = mandos_protocol_version;
818
size_t out_size = strlen(out);
819
ret = (int)TEMP_FAILURE_RETRY(write(tcp_sd, out + written,
820
out_size - written));
823
perror_plus("write");
827
written += (size_t)ret;
828
if(written < out_size){
831
if(out == mandos_protocol_version){
846
fprintf_plus(stderr, "Establishing TLS session with %s\n", ip);
854
/* This casting via intptr_t is to eliminate warning about casting
855
an int to a pointer type. This is exactly how the GnuTLS Guile
856
function "set-session-transport-fd!" does it. */
857
gnutls_transport_set_ptr(session,
858
(gnutls_transport_ptr_t)(intptr_t)tcp_sd);
866
ret = gnutls_handshake(session);
871
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
873
if(ret != GNUTLS_E_SUCCESS){
875
fprintf_plus(stderr, "*** GnuTLS Handshake failed ***\n");
882
/* Read OpenPGP packet that contains the wanted password */
885
fprintf_plus(stderr, "Retrieving OpenPGP encrypted password from"
896
buffer_capacity = incbuffer(&buffer, buffer_length,
898
if(buffer_capacity == 0){
900
perror_plus("incbuffer");
910
sret = gnutls_record_recv(session, buffer+buffer_length,
329
fprintf(stderr, "Bad address: %s\n", ip);
332
to.sin6_port = htons(port);
333
to.sin6_scope_id = if_nametoindex("eth0");
335
ret = connect(tcp_sd, (struct sockaddr *) &to, sizeof(to));
341
ret = initgnutls (&es);
348
gnutls_transport_set_ptr (es.session, (gnutls_transport_ptr_t) tcp_sd);
350
ret = gnutls_handshake (es.session);
352
if (ret != GNUTLS_E_SUCCESS){
353
fprintf(stderr, "\n*** Handshake failed ***\n");
361
if (buffer_length + BUFFER_SIZE > buffer_capacity){
362
buffer = realloc(buffer, buffer_capacity + BUFFER_SIZE);
367
buffer_capacity += BUFFER_SIZE;
370
ret = gnutls_record_recv
371
(es.session, buffer+buffer_length, BUFFER_SIZE);
917
377
case GNUTLS_E_INTERRUPTED:
918
378
case GNUTLS_E_AGAIN:
920
380
case GNUTLS_E_REHANDSHAKE:
922
ret = gnutls_handshake(session);
928
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
930
fprintf_plus(stderr, "*** GnuTLS Re-handshake failed "
381
ret = gnutls_handshake (es.session);
383
fprintf(stderr, "\n*** Handshake failed ***\n");
938
fprintf_plus(stderr, "Unknown error while reading data from"
939
" encrypted session with Mandos server\n");
940
gnutls_bye(session, GNUTLS_SHUT_RDWR);
390
fprintf(stderr, "Unknown error while reading data from encrypted session with mandos server\n");
392
gnutls_bye (es.session, GNUTLS_SHUT_RDWR);
945
buffer_length += (size_t) sret;
950
fprintf_plus(stderr, "Closing TLS session\n");
959
ret = gnutls_bye(session, GNUTLS_SHUT_RDWR);
964
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
966
if(buffer_length > 0){
967
ssize_t decrypted_buffer_size;
968
decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,
969
&decrypted_buffer, mc);
970
if(decrypted_buffer_size >= 0){
973
while(written < (size_t) decrypted_buffer_size){
979
ret = (int)fwrite(decrypted_buffer + written, 1,
980
(size_t)decrypted_buffer_size - written,
982
if(ret == 0 and ferror(stdout)){
985
fprintf_plus(stderr, "Error writing encrypted data: %s\n",
991
written += (size_t)ret;
997
/* Shutdown procedure */
1002
free(decrypted_buffer);
1005
ret = (int)TEMP_FAILURE_RETRY(close(tcp_sd));
1011
perror_plus("close");
1013
gnutls_deinit(session);
396
buffer_length += ret;
400
if (buffer_length > 0){
401
if ((decrypted_buffer_size = gpg_packet_decrypt(buffer, buffer_length, &decrypted_buffer, CERT_ROOT)) == 0){
404
fwrite (decrypted_buffer, 1, decrypted_buffer_size, stdout);
405
free(decrypted_buffer);
412
gnutls_bye (es.session, GNUTLS_SHUT_RDWR);
415
gnutls_deinit (es.session);
416
gnutls_certificate_free_credentials (es.cred);
417
gnutls_global_deinit ();
1023
static void resolve_callback(AvahiSServiceResolver *r,
1024
AvahiIfIndex interface,
1025
AvahiProtocol proto,
1026
AvahiResolverEvent event,
1030
const char *host_name,
1031
const AvahiAddress *address,
1033
AVAHI_GCC_UNUSED AvahiStringList *txt,
1034
AVAHI_GCC_UNUSED AvahiLookupResultFlags
1041
/* Called whenever a service has been resolved successfully or
1050
case AVAHI_RESOLVER_FAILURE:
1051
fprintf_plus(stderr, "(Avahi Resolver) Failed to resolve service "
1052
"'%s' of type '%s' in domain '%s': %s\n", name, type,
1054
avahi_strerror(avahi_server_errno
1055
(((mandos_context*)mc)->server)));
1058
case AVAHI_RESOLVER_FOUND:
1060
char ip[AVAHI_ADDRESS_STR_MAX];
1061
avahi_address_snprint(ip, sizeof(ip), address);
1063
fprintf_plus(stderr, "Mandos server \"%s\" found on %s (%s, %"
1064
PRIdMAX ") on port %" PRIu16 "\n", name,
1065
host_name, ip, (intmax_t)interface, port);
1067
int ret = start_mandos_communication(ip, (in_port_t)port,
1069
avahi_proto_to_af(proto),
1072
avahi_simple_poll_quit(simple_poll);
1074
if(not add_server(ip, (in_port_t)port, interface,
1075
avahi_proto_to_af(proto),
1076
&((mandos_context*)mc)->current_server)){
1077
fprintf_plus(stderr, "Failed to add server \"%s\" to server"
1083
avahi_s_service_resolver_free(r);
1086
static void browse_callback(AvahiSServiceBrowser *b,
1087
AvahiIfIndex interface,
1088
AvahiProtocol protocol,
1089
AvahiBrowserEvent event,
1093
AVAHI_GCC_UNUSED AvahiLookupResultFlags
1100
/* Called whenever a new services becomes available on the LAN or
1101
is removed from the LAN */
1109
case AVAHI_BROWSER_FAILURE:
1111
fprintf_plus(stderr, "(Avahi browser) %s\n",
1112
avahi_strerror(avahi_server_errno
1113
(((mandos_context*)mc)->server)));
1114
avahi_simple_poll_quit(simple_poll);
1117
case AVAHI_BROWSER_NEW:
1118
/* We ignore the returned Avahi resolver object. In the callback
1119
function we free it. If the Avahi server is terminated before
1120
the callback function is called the Avahi server will free the
1123
if(avahi_s_service_resolver_new(((mandos_context*)mc)->server,
1124
interface, protocol, name, type,
1125
domain, protocol, 0,
1126
resolve_callback, mc) == NULL)
1127
fprintf_plus(stderr, "Avahi: Failed to resolve service '%s':"
1129
avahi_strerror(avahi_server_errno
1130
(((mandos_context*)mc)->server)));
1133
case AVAHI_BROWSER_REMOVE:
1136
case AVAHI_BROWSER_ALL_FOR_NOW:
1137
case AVAHI_BROWSER_CACHE_EXHAUSTED:
1139
fprintf_plus(stderr, "No Mandos server found, still"
1146
/* Signal handler that stops main loop after SIGTERM */
1147
static void handle_sigterm(int sig){
1152
signal_received = sig;
1153
int old_errno = errno;
1154
/* set main loop to exit */
1155
if(simple_poll != NULL){
1156
avahi_simple_poll_quit(simple_poll);
1161
bool get_flags(const char *ifname, struct ifreq *ifr){
1165
int s = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1168
perror_plus("socket");
1172
strcpy(ifr->ifr_name, ifname);
1173
ret = ioctl(s, SIOCGIFFLAGS, ifr);
1177
perror_plus("ioctl SIOCGIFFLAGS");
1185
bool good_flags(const char *ifname, const struct ifreq *ifr){
1187
/* Reject the loopback device */
1188
if(ifr->ifr_flags & IFF_LOOPBACK){
1190
fprintf_plus(stderr, "Rejecting loopback interface \"%s\"\n",
1195
/* Accept point-to-point devices only if connect_to is specified */
1196
if(connect_to != NULL and (ifr->ifr_flags & IFF_POINTOPOINT)){
1198
fprintf_plus(stderr, "Accepting point-to-point interface"
1199
" \"%s\"\n", ifname);
1203
/* Otherwise, reject non-broadcast-capable devices */
1204
if(not (ifr->ifr_flags & IFF_BROADCAST)){
1206
fprintf_plus(stderr, "Rejecting non-broadcast interface"
1207
" \"%s\"\n", ifname);
1211
/* Reject non-ARP interfaces (including dummy interfaces) */
1212
if(ifr->ifr_flags & IFF_NOARP){
1214
fprintf_plus(stderr, "Rejecting non-ARP interface \"%s\"\n",
1220
/* Accept this device */
1222
fprintf_plus(stderr, "Interface \"%s\" is good\n", ifname);
1228
* This function determines if a directory entry in /sys/class/net
1229
* corresponds to an acceptable network device.
1230
* (This function is passed to scandir(3) as a filter function.)
1232
int good_interface(const struct dirent *if_entry){
1233
if(if_entry->d_name[0] == '.'){
1238
if(not get_flags(if_entry->d_name, &ifr)){
1240
fprintf_plus(stderr, "Failed to get flags for interface "
1241
"\"%s\"\n", if_entry->d_name);
1246
if(not good_flags(if_entry->d_name, &ifr)){
1253
* This function determines if a network interface is up.
1255
bool interface_is_up(const char *interface){
1257
if(not get_flags(interface, &ifr)){
1259
fprintf_plus(stderr, "Failed to get flags for interface "
1260
"\"%s\"\n", interface);
1265
return (bool)(ifr.ifr_flags & IFF_UP);
1269
* This function determines if a network interface is running
1271
bool interface_is_running(const char *interface){
1273
if(not get_flags(interface, &ifr)){
1275
fprintf_plus(stderr, "Failed to get flags for interface "
1276
"\"%s\"\n", interface);
1281
return (bool)(ifr.ifr_flags & IFF_RUNNING);
1284
int notdotentries(const struct dirent *direntry){
1285
/* Skip "." and ".." */
1286
if(direntry->d_name[0] == '.'
1287
and (direntry->d_name[1] == '\0'
1288
or (direntry->d_name[1] == '.'
1289
and direntry->d_name[2] == '\0'))){
1295
/* Is this directory entry a runnable program? */
1296
int runnable_hook(const struct dirent *direntry){
1301
if((direntry->d_name)[0] == '\0'){
1306
sret = strspn(direntry->d_name, "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
1307
"abcdefghijklmnopqrstuvwxyz"
1310
if((direntry->d_name)[sret] != '\0'){
1311
/* Contains non-allowed characters */
1313
fprintf_plus(stderr, "Ignoring hook \"%s\" with bad name\n",
1319
char *fullname = NULL;
1320
ret = asprintf(&fullname, "%s/%s", hookdir, direntry->d_name);
1322
perror_plus("asprintf");
1326
ret = stat(fullname, &st);
1329
perror_plus("Could not stat hook");
1333
if(not (S_ISREG(st.st_mode))){
1334
/* Not a regular file */
1336
fprintf_plus(stderr, "Ignoring hook \"%s\" - not a file\n",
1341
if(not (st.st_mode & (S_IXUSR | S_IXGRP | S_IXOTH))){
1342
/* Not executable */
1344
fprintf_plus(stderr, "Ignoring hook \"%s\" - not executable\n",
1350
fprintf_plus(stderr, "Hook \"%s\" is acceptable\n",
1356
int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,
1357
mandos_context *mc){
1359
struct timespec now;
1360
struct timespec waited_time;
1361
intmax_t block_time;
1364
if(mc->current_server == NULL){
1366
fprintf_plus(stderr, "Wait until first server is found."
1369
ret = avahi_simple_poll_iterate(s, -1);
1372
fprintf_plus(stderr, "Check current_server if we should run"
1375
/* the current time */
1376
ret = clock_gettime(CLOCK_MONOTONIC, &now);
1378
perror_plus("clock_gettime");
1381
/* Calculating in ms how long time between now and server
1382
who we visted longest time ago. Now - last seen. */
1383
waited_time.tv_sec = (now.tv_sec
1384
- mc->current_server->last_seen.tv_sec);
1385
waited_time.tv_nsec = (now.tv_nsec
1386
- mc->current_server->last_seen.tv_nsec);
1387
/* total time is 10s/10,000ms.
1388
Converting to s from ms by dividing by 1,000,
1389
and ns to ms by dividing by 1,000,000. */
1390
block_time = ((retry_interval
1391
- ((intmax_t)waited_time.tv_sec * 1000))
1392
- ((intmax_t)waited_time.tv_nsec / 1000000));
1395
fprintf_plus(stderr, "Blocking for %" PRIdMAX " ms\n",
1399
if(block_time <= 0){
1400
ret = start_mandos_communication(mc->current_server->ip,
1401
mc->current_server->port,
1402
mc->current_server->if_index,
1403
mc->current_server->af, mc);
1405
avahi_simple_poll_quit(s);
1408
ret = clock_gettime(CLOCK_MONOTONIC,
1409
&mc->current_server->last_seen);
1411
perror_plus("clock_gettime");
1414
mc->current_server = mc->current_server->next;
1415
block_time = 0; /* Call avahi to find new Mandos
1416
servers, but don't block */
1419
ret = avahi_simple_poll_iterate(s, (int)block_time);
1422
if (ret > 0 or errno != EINTR){
1423
return (ret != 1) ? ret : 0;
1429
/* Set effective uid to 0, return errno */
1430
error_t raise_privileges(void){
1431
error_t old_errno = errno;
1432
error_t ret_errno = 0;
1433
if(seteuid(0) == -1){
1435
perror_plus("seteuid");
1441
/* Set effective and real user ID to 0. Return errno. */
1442
error_t raise_privileges_permanently(void){
1443
error_t old_errno = errno;
1444
error_t ret_errno = raise_privileges();
1449
if(setuid(0) == -1){
1451
perror_plus("seteuid");
1457
/* Set effective user ID to unprivileged saved user ID */
1458
error_t lower_privileges(void){
1459
error_t old_errno = errno;
1460
error_t ret_errno = 0;
1461
if(seteuid(uid) == -1){
1463
perror_plus("seteuid");
1469
/* Lower privileges permanently */
1470
error_t lower_privileges_permanently(void){
1471
error_t old_errno = errno;
1472
error_t ret_errno = 0;
1473
if(setuid(uid) == -1){
1475
perror_plus("setuid");
1481
bool run_network_hooks(const char *mode, const char *interface,
1483
struct dirent **direntries;
1484
struct dirent *direntry;
1486
int numhooks = scandir(hookdir, &direntries, runnable_hook,
1489
if(errno == ENOENT){
1491
fprintf_plus(stderr, "Network hook directory \"%s\" not"
1492
" found\n", hookdir);
1495
perror_plus("scandir");
1498
int devnull = open("/dev/null", O_RDONLY);
1499
for(int i = 0; i < numhooks; i++){
1500
direntry = direntries[i];
1501
char *fullname = NULL;
1502
ret = asprintf(&fullname, "%s/%s", hookdir, direntry->d_name);
1504
perror_plus("asprintf");
1508
fprintf_plus(stderr, "Running network hook \"%s\"\n",
1511
pid_t hook_pid = fork();
1514
/* Raise privileges */
1515
raise_privileges_permanently();
1520
perror_plus("setgid");
1522
/* Reset supplementary groups */
1524
ret = setgroups(0, NULL);
1526
perror_plus("setgroups");
1528
dup2(devnull, STDIN_FILENO);
1530
dup2(STDERR_FILENO, STDOUT_FILENO);
1531
ret = setenv("MANDOSNETHOOKDIR", hookdir, 1);
1533
perror_plus("setenv");
1536
ret = setenv("DEVICE", interface, 1);
1538
perror_plus("setenv");
1541
ret = setenv("VERBOSITY", debug ? "1" : "0", 1);
1543
perror_plus("setenv");
1546
ret = setenv("MODE", mode, 1);
1548
perror_plus("setenv");
1552
ret = asprintf(&delaystring, "%f", delay);
1554
perror_plus("asprintf");
1557
ret = setenv("DELAY", delaystring, 1);
1560
perror_plus("setenv");
1564
if(connect_to != NULL){
1565
ret = setenv("CONNECT", connect_to, 1);
1567
perror_plus("setenv");
1571
if(execl(fullname, direntry->d_name, mode, NULL) == -1){
1572
perror_plus("execl");
1573
_exit(EXIT_FAILURE);
1577
if(TEMP_FAILURE_RETRY(waitpid(hook_pid, &status, 0)) == -1){
1578
perror_plus("waitpid");
1582
if(WIFEXITED(status)){
1583
if(WEXITSTATUS(status) != 0){
1584
fprintf_plus(stderr, "Warning: network hook \"%s\" exited"
1585
" with status %d\n", direntry->d_name,
1586
WEXITSTATUS(status));
1590
} else if(WIFSIGNALED(status)){
1591
fprintf_plus(stderr, "Warning: network hook \"%s\" died by"
1592
" signal %d\n", direntry->d_name,
1597
fprintf_plus(stderr, "Warning: network hook \"%s\""
1598
" crashed\n", direntry->d_name);
1605
fprintf_plus(stderr, "Network hook \"%s\" ran successfully\n",
1614
error_t bring_up_interface(const char *const interface,
1617
error_t old_errno = errno;
1618
error_t ret_errno = 0;
1619
int ret, ret_setflags;
1620
struct ifreq network;
1621
unsigned int if_index = if_nametoindex(interface);
1623
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
1633
if(not interface_is_up(interface)){
1634
if(not get_flags(interface, &network) and debug){
1636
fprintf_plus(stderr, "Failed to get flags for interface "
1637
"\"%s\"\n", interface);
1640
network.ifr_flags |= IFF_UP;
1642
sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1645
perror_plus("socket");
1657
fprintf_plus(stderr, "Bringing up interface \"%s\"\n",
1661
/* Raise priviliges */
1665
/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO
1666
messages about the network interface to mess up the prompt */
1667
int ret_linux = klogctl(8, NULL, 5);
1668
bool restore_loglevel = true;
1669
if(ret_linux == -1){
1670
restore_loglevel = false;
1671
perror_plus("klogctl");
1673
#endif /* __linux__ */
1674
ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
1677
if(restore_loglevel){
1678
ret_linux = klogctl(7, NULL, 0);
1679
if(ret_linux == -1){
1680
perror_plus("klogctl");
1683
#endif /* __linux__ */
1685
/* Lower privileges */
1688
/* Close the socket */
1689
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1691
perror_plus("close");
1694
if(ret_setflags == -1){
1696
perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");
1701
fprintf_plus(stderr, "Interface \"%s\" is already up; good\n",
1705
/* Sleep checking until interface is running.
1706
Check every 0.25s, up to total time of delay */
1707
for(int i=0; i < delay * 4; i++){
1708
if(interface_is_running(interface)){
1711
struct timespec sleeptime = { .tv_nsec = 250000000 };
1712
ret = nanosleep(&sleeptime, NULL);
1713
if(ret == -1 and errno != EINTR){
1714
perror_plus("nanosleep");
1722
error_t take_down_interface(const char *const interface){
1724
error_t old_errno = errno;
1725
error_t ret_errno = 0;
1726
int ret, ret_setflags;
1727
struct ifreq network;
1728
unsigned int if_index = if_nametoindex(interface);
1730
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
1734
if(interface_is_up(interface)){
1735
if(not get_flags(interface, &network) and debug){
1737
fprintf_plus(stderr, "Failed to get flags for interface "
1738
"\"%s\"\n", interface);
1741
network.ifr_flags &= ~(short)IFF_UP; /* clear flag */
1743
sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1746
perror_plus("socket");
1752
fprintf_plus(stderr, "Taking down interface \"%s\"\n",
1756
/* Raise priviliges */
1759
ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
1762
/* Lower privileges */
1765
/* Close the socket */
1766
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1768
perror_plus("close");
1771
if(ret_setflags == -1){
1773
perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");
1778
fprintf_plus(stderr, "Interface \"%s\" is already down; odd\n",
1786
int main(int argc, char *argv[]){
1787
mandos_context mc = { .server = NULL, .dh_bits = 1024,
1788
.priority = "SECURE256:!CTYPE-X.509:"
1789
"+CTYPE-OPENPGP", .current_server = NULL,
1790
.interfaces = NULL, .interfaces_size = 0 };
1791
AvahiSServiceBrowser *sb = NULL;
1796
int exitcode = EXIT_SUCCESS;
1797
char *interfaces_to_take_down = NULL;
1798
size_t interfaces_to_take_down_size = 0;
1799
char tempdir[] = "/tmp/mandosXXXXXX";
1800
bool tempdir_created = false;
1801
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
1802
const char *seckey = PATHDIR "/" SECKEY;
1803
const char *pubkey = PATHDIR "/" PUBKEY;
1804
char *interfaces_hooks = NULL;
1805
size_t interfaces_hooks_size = 0;
1807
bool gnutls_initialized = false;
1808
bool gpgme_initialized = false;
1810
double retry_interval = 10; /* 10s between trying a server and
1811
retrying the same server again */
1813
struct sigaction old_sigterm_action = { .sa_handler = SIG_DFL };
1814
struct sigaction sigterm_action = { .sa_handler = handle_sigterm };
1819
/* Lower any group privileges we might have, just to be safe */
1823
perror_plus("setgid");
1826
/* Lower user privileges (temporarily) */
1830
perror_plus("seteuid");
1838
struct argp_option options[] = {
1839
{ .name = "debug", .key = 128,
1840
.doc = "Debug mode", .group = 3 },
1841
{ .name = "connect", .key = 'c',
1842
.arg = "ADDRESS:PORT",
1843
.doc = "Connect directly to a specific Mandos server",
1845
{ .name = "interface", .key = 'i',
1847
.doc = "Network interface that will be used to search for"
1850
{ .name = "seckey", .key = 's',
1852
.doc = "OpenPGP secret key file base name",
1854
{ .name = "pubkey", .key = 'p',
1856
.doc = "OpenPGP public key file base name",
1858
{ .name = "dh-bits", .key = 129,
1860
.doc = "Bit length of the prime number used in the"
1861
" Diffie-Hellman key exchange",
1863
{ .name = "priority", .key = 130,
1865
.doc = "GnuTLS priority string for the TLS handshake",
1867
{ .name = "delay", .key = 131,
1869
.doc = "Maximum delay to wait for interface startup",
1871
{ .name = "retry", .key = 132,
1873
.doc = "Retry interval used when denied by the Mandos server",
1875
{ .name = "network-hook-dir", .key = 133,
1877
.doc = "Directory where network hooks are located",
1880
* These reproduce what we would get without ARGP_NO_HELP
1882
{ .name = "help", .key = '?',
1883
.doc = "Give this help list", .group = -1 },
1884
{ .name = "usage", .key = -3,
1885
.doc = "Give a short usage message", .group = -1 },
1886
{ .name = "version", .key = 'V',
1887
.doc = "Print program version", .group = -1 },
1891
error_t parse_opt(int key, char *arg,
1892
struct argp_state *state){
1895
case 128: /* --debug */
1898
case 'c': /* --connect */
1901
case 'i': /* --interface */
1902
ret_errno = argz_add_sep(&mc.interfaces, &mc.interfaces_size,
1905
argp_error(state, "%s", strerror(ret_errno));
1908
case 's': /* --seckey */
1911
case 'p': /* --pubkey */
1914
case 129: /* --dh-bits */
1916
tmpmax = strtoimax(arg, &tmp, 10);
1917
if(errno != 0 or tmp == arg or *tmp != '\0'
1918
or tmpmax != (typeof(mc.dh_bits))tmpmax){
1919
argp_error(state, "Bad number of DH bits");
1921
mc.dh_bits = (typeof(mc.dh_bits))tmpmax;
1923
case 130: /* --priority */
1926
case 131: /* --delay */
1928
delay = strtof(arg, &tmp);
1929
if(errno != 0 or tmp == arg or *tmp != '\0'){
1930
argp_error(state, "Bad delay");
1932
case 132: /* --retry */
1934
retry_interval = strtod(arg, &tmp);
1935
if(errno != 0 or tmp == arg or *tmp != '\0'
1936
or (retry_interval * 1000) > INT_MAX
1937
or retry_interval < 0){
1938
argp_error(state, "Bad retry interval");
1941
case 133: /* --network-hook-dir */
1945
* These reproduce what we would get without ARGP_NO_HELP
1947
case '?': /* --help */
1948
argp_state_help(state, state->out_stream,
1949
(ARGP_HELP_STD_HELP | ARGP_HELP_EXIT_ERR)
1950
& ~(unsigned int)ARGP_HELP_EXIT_OK);
1951
case -3: /* --usage */
1952
argp_state_help(state, state->out_stream,
1953
ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);
1954
case 'V': /* --version */
1955
fprintf_plus(state->out_stream, "%s\n", argp_program_version);
1956
exit(argp_err_exit_status);
1959
return ARGP_ERR_UNKNOWN;
1964
struct argp argp = { .options = options, .parser = parse_opt,
1966
.doc = "Mandos client -- Get and decrypt"
1967
" passwords from a Mandos server" };
1968
ret = argp_parse(&argp, argc, argv,
1969
ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);
1976
perror_plus("argp_parse");
1977
exitcode = EX_OSERR;
1980
exitcode = EX_USAGE;
1986
/* Work around Debian bug #633582:
1987
<http://bugs.debian.org/633582> */
1989
/* Re-raise priviliges */
1990
if(raise_privileges() == 0){
1993
if(strcmp(seckey, PATHDIR "/" SECKEY) == 0){
1994
int seckey_fd = open(seckey, O_RDONLY);
1995
if(seckey_fd == -1){
1996
perror_plus("open");
1998
ret = (int)TEMP_FAILURE_RETRY(fstat(seckey_fd, &st));
2000
perror_plus("fstat");
2002
if(S_ISREG(st.st_mode)
2003
and st.st_uid == 0 and st.st_gid == 0){
2004
ret = fchown(seckey_fd, uid, gid);
2006
perror_plus("fchown");
2010
TEMP_FAILURE_RETRY(close(seckey_fd));
2014
if(strcmp(pubkey, PATHDIR "/" PUBKEY) == 0){
2015
int pubkey_fd = open(pubkey, O_RDONLY);
2016
if(pubkey_fd == -1){
2017
perror_plus("open");
2019
ret = (int)TEMP_FAILURE_RETRY(fstat(pubkey_fd, &st));
2021
perror_plus("fstat");
2023
if(S_ISREG(st.st_mode)
2024
and st.st_uid == 0 and st.st_gid == 0){
2025
ret = fchown(pubkey_fd, uid, gid);
2027
perror_plus("fchown");
2031
TEMP_FAILURE_RETRY(close(pubkey_fd));
2035
/* Lower privileges */
2040
/* Remove invalid interface names (except "none") */
2042
char *interface = NULL;
2043
while((interface = argz_next(mc.interfaces, mc.interfaces_size,
2045
if(strcmp(interface, "none") != 0
2046
and if_nametoindex(interface) == 0){
2047
if(interface[0] != '\0'){
2048
fprintf_plus(stderr, "Not using nonexisting interface"
2049
" \"%s\"\n", interface);
2051
argz_delete(&mc.interfaces, &mc.interfaces_size, interface);
2057
/* Run network hooks */
2059
if(mc.interfaces != NULL){
2060
interfaces_hooks = malloc(mc.interfaces_size);
2061
if(interfaces_hooks == NULL){
2062
perror_plus("malloc");
2065
memcpy(interfaces_hooks, mc.interfaces, mc.interfaces_size);
2066
interfaces_hooks_size = mc.interfaces_size;
2067
argz_stringify(interfaces_hooks, interfaces_hooks_size,
2070
if(not run_network_hooks("start", interfaces_hooks != NULL ?
2071
interfaces_hooks : "", delay)){
421
static AvahiSimplePoll *simple_poll = NULL;
422
static AvahiServer *server = NULL;
424
static void resolve_callback(
425
AvahiSServiceResolver *r,
426
AVAHI_GCC_UNUSED AvahiIfIndex interface,
427
AVAHI_GCC_UNUSED AvahiProtocol protocol,
428
AvahiResolverEvent event,
432
const char *host_name,
433
const AvahiAddress *address,
435
AvahiStringList *txt,
436
AvahiLookupResultFlags flags,
437
AVAHI_GCC_UNUSED void* userdata) {
441
/* Called whenever a service has been resolved successfully or timed out */
444
case AVAHI_RESOLVER_FAILURE:
445
fprintf(stderr, "(Resolver) Failed to resolve service '%s' of type '%s' in domain '%s': %s\n", name, type, domain, avahi_strerror(avahi_server_errno(server)));
448
case AVAHI_RESOLVER_FOUND: {
449
char ip[AVAHI_ADDRESS_STR_MAX];
450
avahi_address_snprint(ip, sizeof(ip), address);
451
int ret = start_mandos_communcation(ip, port);
459
avahi_s_service_resolver_free(r);
462
static void browse_callback(
463
AvahiSServiceBrowser *b,
464
AvahiIfIndex interface,
465
AvahiProtocol protocol,
466
AvahiBrowserEvent event,
470
AVAHI_GCC_UNUSED AvahiLookupResultFlags flags,
473
AvahiServer *s = userdata;
476
/* Called whenever a new services becomes available on the LAN or is removed from the LAN */
480
case AVAHI_BROWSER_FAILURE:
482
fprintf(stderr, "(Browser) %s\n", avahi_strerror(avahi_server_errno(server)));
483
avahi_simple_poll_quit(simple_poll);
486
case AVAHI_BROWSER_NEW:
487
/* We ignore the returned resolver object. In the callback
488
function we free it. If the server is terminated before
489
the callback function is called the server will free
490
the resolver for us. */
492
if (!(avahi_s_service_resolver_new(s, interface, protocol, name, type, domain, AVAHI_PROTO_INET6, 0, resolve_callback, s)))
493
fprintf(stderr, "Failed to resolve service '%s': %s\n", name, avahi_strerror(avahi_server_errno(s)));
497
case AVAHI_BROWSER_REMOVE:
500
case AVAHI_BROWSER_ALL_FOR_NOW:
501
case AVAHI_BROWSER_CACHE_EXHAUSTED:
506
int main(AVAHI_GCC_UNUSED int argc, AVAHI_GCC_UNUSED char*argv[]) {
507
AvahiServerConfig config;
508
AvahiSServiceBrowser *sb = NULL;
2077
512
avahi_set_log_function(empty_log);
2080
/* Initialize Avahi early so avahi_simple_poll_quit() can be called
2081
from the signal handler */
2082
/* Initialize the pseudo-RNG for Avahi */
2083
srand((unsigned int) time(NULL));
2084
simple_poll = avahi_simple_poll_new();
2085
if(simple_poll == NULL){
2086
fprintf_plus(stderr,
2087
"Avahi: Failed to create simple poll object.\n");
2088
exitcode = EX_UNAVAILABLE;
2092
sigemptyset(&sigterm_action.sa_mask);
2093
ret = sigaddset(&sigterm_action.sa_mask, SIGINT);
2095
perror_plus("sigaddset");
2096
exitcode = EX_OSERR;
2099
ret = sigaddset(&sigterm_action.sa_mask, SIGHUP);
2101
perror_plus("sigaddset");
2102
exitcode = EX_OSERR;
2105
ret = sigaddset(&sigterm_action.sa_mask, SIGTERM);
2107
perror_plus("sigaddset");
2108
exitcode = EX_OSERR;
2111
/* Need to check if the handler is SIG_IGN before handling:
2112
| [[info:libc:Initial Signal Actions]] |
2113
| [[info:libc:Basic Signal Handling]] |
2115
ret = sigaction(SIGINT, NULL, &old_sigterm_action);
2117
perror_plus("sigaction");
2120
if(old_sigterm_action.sa_handler != SIG_IGN){
2121
ret = sigaction(SIGINT, &sigterm_action, NULL);
2123
perror_plus("sigaction");
2124
exitcode = EX_OSERR;
2128
ret = sigaction(SIGHUP, NULL, &old_sigterm_action);
2130
perror_plus("sigaction");
2133
if(old_sigterm_action.sa_handler != SIG_IGN){
2134
ret = sigaction(SIGHUP, &sigterm_action, NULL);
2136
perror_plus("sigaction");
2137
exitcode = EX_OSERR;
2141
ret = sigaction(SIGTERM, NULL, &old_sigterm_action);
2143
perror_plus("sigaction");
2146
if(old_sigterm_action.sa_handler != SIG_IGN){
2147
ret = sigaction(SIGTERM, &sigterm_action, NULL);
2149
perror_plus("sigaction");
2150
exitcode = EX_OSERR;
2155
/* If no interfaces were specified, make a list */
2156
if(mc.interfaces == NULL){
2157
struct dirent **direntries;
2158
/* Look for any good interfaces */
2159
ret = scandir(sys_class_net, &direntries, good_interface,
2162
/* Add all found interfaces to interfaces list */
2163
for(int i = 0; i < ret; ++i){
2164
ret_errno = argz_add(&mc.interfaces, &mc.interfaces_size,
2165
direntries[i]->d_name);
2167
perror_plus("argz_add");
2171
fprintf_plus(stderr, "Will use interface \"%s\"\n",
2172
direntries[i]->d_name);
2178
fprintf_plus(stderr, "Could not find a network interface\n");
2179
exitcode = EXIT_FAILURE;
2184
/* Bring up interfaces which are down */
2186
char *interface = NULL;
2187
while((interface = argz_next(mc.interfaces, mc.interfaces_size,
2189
/* If interface name is "none", stop bringing up interfaces.
2190
Also remove all instances of "none" from the list */
2191
if(strcmp(interface, "none") == 0){
2192
argz_delete(&mc.interfaces, &mc.interfaces_size,
2195
while((interface = argz_next(mc.interfaces,
2196
mc.interfaces_size, interface))){
2197
if(strcmp(interface, "none") == 0){
2198
argz_delete(&mc.interfaces, &mc.interfaces_size,
2205
bool interface_was_up = interface_is_up(interface);
2206
ret = bring_up_interface(interface, delay);
2207
if(not interface_was_up){
2210
perror_plus("Failed to bring up interface");
2212
ret_errno = argz_add(&interfaces_to_take_down,
2213
&interfaces_to_take_down_size,
2218
if(debug and (interfaces_to_take_down == NULL)){
2219
fprintf_plus(stderr, "No interfaces were brought up\n");
2223
/* If we only got one interface, explicitly use only that one */
2224
if(argz_count(mc.interfaces, mc.interfaces_size) == 1){
2226
fprintf_plus(stderr, "Using only interface \"%s\"\n",
2229
if_index = (AvahiIfIndex)if_nametoindex(mc.interfaces);
2236
ret = init_gnutls_global(pubkey, seckey, &mc);
2238
fprintf_plus(stderr, "init_gnutls_global failed\n");
2239
exitcode = EX_UNAVAILABLE;
2242
gnutls_initialized = true;
2249
if(mkdtemp(tempdir) == NULL){
2250
perror_plus("mkdtemp");
2253
tempdir_created = true;
2259
if(not init_gpgme(pubkey, seckey, tempdir, &mc)){
2260
fprintf_plus(stderr, "init_gpgme failed\n");
2261
exitcode = EX_UNAVAILABLE;
2264
gpgme_initialized = true;
2271
if(connect_to != NULL){
2272
/* Connect directly, do not use Zeroconf */
2273
/* (Mainly meant for debugging) */
2274
char *address = strrchr(connect_to, ':');
2276
if(address == NULL){
2277
fprintf_plus(stderr, "No colon in address\n");
2278
exitcode = EX_USAGE;
2288
tmpmax = strtoimax(address+1, &tmp, 10);
2289
if(errno != 0 or tmp == address+1 or *tmp != '\0'
2290
or tmpmax != (in_port_t)tmpmax){
2291
fprintf_plus(stderr, "Bad port number\n");
2292
exitcode = EX_USAGE;
2300
port = (in_port_t)tmpmax;
2302
/* Colon in address indicates IPv6 */
2304
if(strchr(connect_to, ':') != NULL){
2306
/* Accept [] around IPv6 address - see RFC 5952 */
2307
if(connect_to[0] == '[' and address[-1] == ']')
2315
address = connect_to;
2321
while(not quit_now){
2322
ret = start_mandos_communication(address, port, if_index, af,
2324
if(quit_now or ret == 0){
2328
fprintf_plus(stderr, "Retrying in %d seconds\n",
2329
(int)retry_interval);
2331
sleep((int)retry_interval);
2335
exitcode = EXIT_SUCCESS;
2346
AvahiServerConfig config;
2347
/* Do not publish any local Zeroconf records */
514
/* Initialize the psuedo-RNG */
517
/* Allocate main loop object */
518
if (!(simple_poll = avahi_simple_poll_new())) {
519
fprintf(stderr, "Failed to create simple poll object.\n");
523
/* Do not publish any local records */
2348
524
avahi_server_config_init(&config);
2349
525
config.publish_hinfo = 0;
2350
526
config.publish_addresses = 0;
2351
527
config.publish_workstation = 0;
2352
528
config.publish_domain = 0;
530
/* /\* Set a unicast DNS server for wide area DNS-SD *\/ */
531
/* avahi_address_parse("193.11.177.11", AVAHI_PROTO_UNSPEC, &config.wide_area_servers[0]); */
532
/* config.n_wide_area_servers = 1; */
533
/* config.enable_wide_area = 1; */
2354
535
/* Allocate a new server */
2355
mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),
2356
&config, NULL, NULL, &ret_errno);
2358
/* Free the Avahi configuration data */
536
server = avahi_server_new(avahi_simple_poll_get(simple_poll), &config, NULL, NULL, &error);
538
/* Free the configuration data */
2359
539
avahi_server_config_free(&config);
2362
/* Check if creating the Avahi server object succeeded */
2363
if(mc.server == NULL){
2364
fprintf_plus(stderr, "Failed to create Avahi server: %s\n",
2365
avahi_strerror(ret_errno));
2366
exitcode = EX_UNAVAILABLE;
2374
/* Create the Avahi service browser */
2375
sb = avahi_s_service_browser_new(mc.server, if_index,
2376
AVAHI_PROTO_UNSPEC, "_mandos._tcp",
2377
NULL, 0, browse_callback,
2380
fprintf_plus(stderr, "Failed to create service browser: %s\n",
2381
avahi_strerror(avahi_server_errno(mc.server)));
2382
exitcode = EX_UNAVAILABLE;
2390
/* Run the main loop */
2393
fprintf_plus(stderr, "Starting Avahi loop search\n");
2396
ret = avahi_loop_with_timeout(simple_poll,
2397
(int)(retry_interval * 1000), &mc);
2399
fprintf_plus(stderr, "avahi_loop_with_timeout exited %s\n",
2400
(ret == 0) ? "successfully" : "with error");
2406
fprintf_plus(stderr, "%s exiting\n", argv[0]);
2409
/* Cleanup things */
2410
free(mc.interfaces);
2413
avahi_s_service_browser_free(sb);
2415
if(mc.server != NULL)
2416
avahi_server_free(mc.server);
2418
if(simple_poll != NULL)
2419
avahi_simple_poll_free(simple_poll);
2421
if(gnutls_initialized){
2422
gnutls_certificate_free_credentials(mc.cred);
2423
gnutls_global_deinit();
2424
gnutls_dh_params_deinit(mc.dh_params);
2427
if(gpgme_initialized){
2428
gpgme_release(mc.ctx);
2431
/* Cleans up the circular linked list of Mandos servers the client
2433
if(mc.current_server != NULL){
2434
mc.current_server->prev->next = NULL;
2435
while(mc.current_server != NULL){
2436
server *next = mc.current_server->next;
2437
free(mc.current_server);
2438
mc.current_server = next;
2442
/* Re-raise priviliges */
2446
/* Run network hooks */
2447
run_network_hooks("stop", interfaces_hooks != NULL ?
2448
interfaces_hooks : "", delay);
2450
/* Take down the network interfaces which were brought up */
2452
char *interface = NULL;
2453
while((interface=argz_next(interfaces_to_take_down,
2454
interfaces_to_take_down_size,
2456
ret_errno = take_down_interface(interface);
2459
perror_plus("Failed to take down interface");
2462
if(debug and (interfaces_to_take_down == NULL)){
2463
fprintf_plus(stderr, "No interfaces needed to be taken"
2468
lower_privileges_permanently();
2471
free(interfaces_to_take_down);
2472
free(interfaces_hooks);
2474
/* Removes the GPGME temp directory and all files inside */
2475
if(tempdir_created){
2476
struct dirent **direntries = NULL;
2477
struct dirent *direntry = NULL;
2478
int numentries = scandir(tempdir, &direntries, notdotentries,
2480
if (numentries > 0){
2481
for(int i = 0; i < numentries; i++){
2482
direntry = direntries[i];
2483
char *fullname = NULL;
2484
ret = asprintf(&fullname, "%s/%s", tempdir,
2487
perror_plus("asprintf");
2490
ret = remove(fullname);
2492
fprintf_plus(stderr, "remove(\"%s\"): %s\n", fullname,
2499
/* need to clean even if 0 because man page doesn't specify */
2501
if (numentries == -1){
2502
perror_plus("scandir");
2504
ret = rmdir(tempdir);
2505
if(ret == -1 and errno != ENOENT){
2506
perror_plus("rmdir");
2511
sigemptyset(&old_sigterm_action.sa_mask);
2512
old_sigterm_action.sa_handler = SIG_DFL;
2513
ret = (int)TEMP_FAILURE_RETRY(sigaction(signal_received,
2514
&old_sigterm_action,
2517
perror_plus("sigaction");
2520
ret = raise(signal_received);
2521
} while(ret != 0 and errno == EINTR);
2523
perror_plus("raise");
2526
TEMP_FAILURE_RETRY(pause());
541
/* Check wether creating the server object succeeded */
543
fprintf(stderr, "Failed to create server: %s\n", avahi_strerror(error));
547
/* Create the service browser */
548
if (!(sb = avahi_s_service_browser_new(server, if_nametoindex("eth0"), AVAHI_PROTO_INET6, "_mandos._tcp", NULL, 0, browse_callback, server))) {
549
fprintf(stderr, "Failed to create service browser: %s\n", avahi_strerror(avahi_server_errno(server)));
553
/* Run the main loop */
554
avahi_simple_poll_loop(simple_poll);
562
avahi_s_service_browser_free(sb);
565
avahi_server_free(server);
568
avahi_simple_poll_free(simple_poll);