107
33
#include <avahi-common/malloc.h>
108
34
#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,
37
#include <sys/types.h> /* socket(), setsockopt(), inet_pton() */
38
#include <sys/socket.h> /* socket(), setsockopt(), struct sockaddr_in6, struct in6_addr, inet_pton() */
39
#include <gnutls/gnutls.h> /* ALL GNUTLS STUFF */
40
#include <gnutls/openpgp.h> /* gnutls with openpgp stuff */
42
#include <unistd.h> /* close() */
43
#include <netinet/in.h>
44
#include <stdbool.h> /* true */
45
#include <string.h> /* memset */
46
#include <arpa/inet.h> /* inet_pton() */
47
#include <iso646.h> /* not */
50
#include <errno.h> /* perror() */
55
#define CERT_ROOT "/conf/conf.d/cryptkeyreq/"
57
#define CERTFILE CERT_ROOT "openpgp-client.txt"
58
#define KEYFILE CERT_ROOT "openpgp-client-key.txt"
127
59
#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"
134
62
bool debug = false;
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 */
65
gnutls_session_t session;
158
66
gnutls_certificate_credentials_t cred;
159
unsigned int dh_bits;
160
67
gnutls_dh_params_t dh_params;
161
const char *priority;
71
ssize_t gpg_packet_decrypt (char *packet, size_t packet_size, char **new_packet, char *homedir){
72
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 (int)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){
76
size_t new_packet_capacity = 0;
77
size_t new_packet_length = 0;
253
78
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");
81
fprintf(stderr, "Attempting to decrypt password from gpg packet\n");
296
85
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));
86
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));
88
/* Set GPGME home directory */
89
rc = gpgme_get_engine_info (&engine_info);
90
if (rc != GPG_ERR_NO_ERROR){
91
fprintf(stderr, "bad gpgme_get_engine_info: %s: %s\n",
92
gpgme_strsource(rc), gpgme_strerror(rc));
311
95
while(engine_info != NULL){
312
96
if(engine_info->protocol == GPGME_PROTOCOL_OpenPGP){
313
97
gpgme_set_engine_info(GPGME_PROTOCOL_OpenPGP,
314
engine_info->file_name, tempdir);
98
engine_info->file_name, homedir);
317
101
engine_info = engine_info->next;
319
103
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));
104
fprintf(stderr, "Could not set home dir to %s\n", homedir);
108
/* Create new GPGME data buffer from packet buffer */
109
rc = gpgme_data_new_from_mem(&dh_crypto, packet, packet_size, 0);
110
if (rc != GPG_ERR_NO_ERROR){
111
fprintf(stderr, "bad gpgme_data_new_from_mem: %s: %s\n",
112
gpgme_strsource(rc), gpgme_strerror(rc));
368
116
/* Create new empty GPGME data buffer for the plaintext */
369
117
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;
118
if (rc != GPG_ERR_NO_ERROR){
119
fprintf(stderr, "bad gpgme_data_new: %s: %s\n",
120
gpgme_strsource(rc), gpgme_strerror(rc));
124
/* Create new GPGME "context" */
125
rc = gpgme_new(&ctx);
126
if (rc != GPG_ERR_NO_ERROR){
127
fprintf(stderr, "bad gpgme_new: %s: %s\n",
128
gpgme_strsource(rc), gpgme_strerror(rc));
132
/* Decrypt data from the FILE pointer to the plaintext data buffer */
133
rc = gpgme_op_decrypt(ctx, dh_crypto, dh_plain);
134
if (rc != GPG_ERR_NO_ERROR){
135
fprintf(stderr, "bad gpgme_op_decrypt: %s: %s\n",
136
gpgme_strsource(rc), gpgme_strerror(rc));
141
fprintf(stderr, "decryption of gpg packet succeeded\n");
145
gpgme_decrypt_result_t result;
146
result = gpgme_op_decrypt_result(ctx);
148
fprintf(stderr, "gpgme_op_decrypt_result failed\n");
150
fprintf(stderr, "Unsupported algorithm: %s\n", result->unsupported_algorithm);
151
fprintf(stderr, "Wrong key usage: %d\n", result->wrong_key_usage);
152
if(result->file_name != NULL){
153
fprintf(stderr, "File name: %s\n", result->file_name);
155
gpgme_recipient_t recipient;
156
recipient = result->recipients;
400
158
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
159
fprintf(stderr, "Public key algorithm: %s\n",
160
gpgme_pubkey_algo_name(recipient->pubkey_algo));
161
fprintf(stderr, "Key ID: %s\n", recipient->keyid);
162
fprintf(stderr, "Secret key available: %s\n",
163
recipient->status == GPG_ERR_NO_SECKEY ? "No" : "Yes");
408
164
recipient = recipient->next;
416
fprintf_plus(stderr, "Decryption of OpenPGP data succeeded\n");
170
/* Delete the GPGME FILE pointer cryptotext data buffer */
171
gpgme_data_release(dh_crypto);
419
173
/* 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;
174
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;
178
if (new_packet_length + BUFFER_SIZE > new_packet_capacity){
179
*new_packet = realloc(*new_packet, new_packet_capacity + BUFFER_SIZE);
180
if (*new_packet == NULL){
184
new_packet_capacity += BUFFER_SIZE;
437
ret = gpgme_data_read(dh_plain, *plaintext + plaintext_length,
187
ret = gpgme_data_read(dh_plain, *new_packet + new_packet_length, BUFFER_SIZE);
439
188
/* Print the data, if any */
190
/* If password is empty, then a incorrect error will be printed */
445
perror_plus("gpgme_data_read");
446
plaintext_length = -1;
194
perror("gpgme_data_read");
449
plaintext_length += ret;
197
new_packet_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");
201
fprintf(stderr, "decrypted password is: %s\n", *new_packet);
462
/* Delete the GPGME cryptotext data buffer */
463
gpgme_data_release(dh_crypto);
465
/* Delete the GPGME plaintext data buffer */
204
/* Delete the GPGME plaintext data buffer */
466
205
gpgme_data_release(dh_plain);
467
return plaintext_length;
206
return new_packet_length;
470
static const char * safer_gnutls_strerror(int value){
471
const char *ret = gnutls_strerror(value);
209
static const char * safer_gnutls_strerror (int value) {
210
const char *ret = gnutls_strerror (value);
473
212
ret = "(unknown)";
477
/* GnuTLS log function callback */
478
static void debuggnutls(__attribute__((unused)) int level,
480
fprintf_plus(stderr, "GnuTLS: %s", string);
216
void debuggnutls(int level, const char* string){
217
fprintf(stderr, "%s", string);
483
static int init_gnutls_global(const char *pubkeyfilename,
484
const char *seckeyfilename,
220
int initgnutls(encrypted_session *es){
489
fprintf_plus(stderr, "Initializing GnuTLS\n");
225
fprintf(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));
229
if ((ret = gnutls_global_init ())
230
!= GNUTLS_E_SUCCESS) {
231
fprintf (stderr, "global_init: %s\n", safer_gnutls_strerror(ret));
500
/* "Use a log level over 10 to enable all debugging options."
503
236
gnutls_global_set_log_level(11);
504
237
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();
241
/* openpgp credentials */
242
if ((ret = gnutls_certificate_allocate_credentials (&es->cred))
243
!= GNUTLS_E_SUCCESS) {
244
fprintf (stderr, "memory error: %s\n", safer_gnutls_strerror(ret));
517
fprintf_plus(stderr, "Attempting to use OpenPGP public key %s and"
518
" secret key %s as GnuTLS credentials\n",
249
fprintf(stderr, "Attempting to use openpgp certificate %s"
250
" and keyfile %s as gnutls credentials\n", CERTFILE, KEYFILE);
523
253
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);
254
(es->cred, CERTFILE, KEYFILE, GNUTLS_OPENPGP_FMT_BASE64);
255
if (ret != GNUTLS_E_SUCCESS) {
257
(stderr, "Error[%d] while reading the OpenPGP key pair ('%s', '%s')\n",
258
ret, CERTFILE, KEYFILE);
259
fprintf(stdout, "The Error is: %s\n",
260
safer_gnutls_strerror(ret));
264
//Gnutls server initialization
265
if ((ret = gnutls_dh_params_init (&es->dh_params))
266
!= GNUTLS_E_SUCCESS) {
267
fprintf (stderr, "Error in dh parameter initialization: %s\n",
268
safer_gnutls_strerror(ret));
272
if ((ret = gnutls_dh_params_generate2 (es->dh_params, DH_BITS))
273
!= GNUTLS_E_SUCCESS) {
274
fprintf (stderr, "Error in prime generation: %s\n",
275
safer_gnutls_strerror(ret));
279
gnutls_certificate_set_dh_params (es->cred, es->dh_params);
281
// Gnutls session creation
282
if ((ret = gnutls_init (&es->session, GNUTLS_SERVER))
283
!= GNUTLS_E_SUCCESS){
284
fprintf(stderr, "Error in gnutls session initialization: %s\n",
285
safer_gnutls_strerror(ret));
288
if ((ret = gnutls_priority_set_direct (es->session, "NORMAL", &err))
289
!= GNUTLS_E_SUCCESS) {
290
fprintf(stderr, "Syntax error at: %s\n", err);
291
fprintf(stderr, "Gnutls error: %s\n",
292
safer_gnutls_strerror(ret));
296
if ((ret = gnutls_credentials_set
297
(es->session, GNUTLS_CRD_CERTIFICATE, es->cred))
298
!= GNUTLS_E_SUCCESS) {
299
fprintf(stderr, "Error setting a credentials set: %s\n",
300
safer_gnutls_strerror(ret));
611
304
/* ignore client certificate if any. */
612
gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);
305
gnutls_certificate_server_set_request (es->session, GNUTLS_CERT_IGNORE);
614
gnutls_dh_set_prime_bits(*session, mc->dh_bits);
307
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){}
312
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;
314
int start_mandos_communication(char *ip, uint16_t port){
316
struct sockaddr_in6 to;
317
encrypted_session es;
633
318
char *buffer = NULL;
634
char *decrypted_buffer = NULL;
319
char *decrypted_buffer;
635
320
size_t buffer_length = 0;
636
321
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 the interface is specified and we have a list of interfaces */
663
if(if_index != AVAHI_IF_UNSPEC and mc->interfaces != NULL){
664
/* Check if the interface is one of the interfaces we are using */
667
char *interface = NULL;
668
while((interface=argz_next(mc->interfaces, mc->interfaces_size,
670
if(if_nametoindex(interface) == (unsigned int)if_index){
677
/* This interface does not match any in the list, so we don't
678
connect to the server */
680
char interface[IF_NAMESIZE];
681
if(if_indextoname((unsigned int)if_index, interface) == NULL){
682
perror_plus("if_indextoname");
684
fprintf_plus(stderr, "Skipping server on non-used interface"
686
if_indextoname((unsigned int)if_index,
694
ret = init_gnutls_session(&session, mc);
700
fprintf_plus(stderr, "Setting up a TCP connection to %s, port %"
701
PRIuMAX "\n", ip, (uintmax_t)port);
704
tcp_sd = socket(pf, SOCK_STREAM, 0);
707
perror_plus("socket");
717
memset(&to, 0, sizeof(to));
719
to.in6.sin6_family = (sa_family_t)af;
720
ret = inet_pton(af, ip, &to.in6.sin6_addr);
722
to.in.sin_family = (sa_family_t)af;
723
ret = inet_pton(af, ip, &to.in.sin_addr);
727
perror_plus("inet_pton");
322
ssize_t decrypted_buffer_size;
324
const char interface[] = "eth0";
327
fprintf(stderr, "Setting up a tcp connection to %s\n", ip);
330
tcp_sd = socket(PF_INET6, SOCK_STREAM, 0);
337
fprintf(stderr, "Binding to interface %s\n", interface);
340
ret = setsockopt(tcp_sd, SOL_SOCKET, SO_BINDTODEVICE, interface, 5);
342
perror("setsockopt bindtodevice");
346
memset(&to,0,sizeof(to));
347
to.sin6_family = AF_INET6;
348
ret = inet_pton(AF_INET6, ip, &to.sin6_addr);
733
fprintf_plus(stderr, "Bad address: %s\n", ip);
738
to.in6.sin6_port = htons(port);
739
if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */
740
(&to.in6.sin6_addr)){ /* -Wstrict-aliasing=2 or lower and
742
if(if_index == AVAHI_IF_UNSPEC){
743
fprintf_plus(stderr, "An IPv6 link-local address is"
744
" incomplete without a network interface\n");
748
/* Set the network interface number as scope */
749
to.in6.sin6_scope_id = (uint32_t)if_index;
752
to.in.sin_port = htons(port); /* Spurious warnings from
754
-Wunreachable-code */
763
if(af == AF_INET6 and if_index != AVAHI_IF_UNSPEC){
764
char interface[IF_NAMESIZE];
765
if(if_indextoname((unsigned int)if_index, interface) == NULL){
766
perror_plus("if_indextoname");
768
fprintf_plus(stderr, "Connection to: %s%%%s, port %" PRIuMAX
769
"\n", ip, interface, (uintmax_t)port);
772
fprintf_plus(stderr, "Connection to: %s, port %" PRIuMAX "\n",
773
ip, (uintmax_t)port);
775
char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?
776
INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";
779
pcret = inet_ntop(af, &(to.in6.sin6_addr), addrstr,
782
pcret = inet_ntop(af, &(to.in.sin_addr), addrstr,
786
perror_plus("inet_ntop");
788
if(strcmp(addrstr, ip) != 0){
789
fprintf_plus(stderr, "Canonical address form: %s\n", addrstr);
800
ret = connect(tcp_sd, &to.in6, sizeof(to));
802
ret = connect(tcp_sd, &to.in, sizeof(to)); /* IPv4 */
805
if ((errno != ECONNREFUSED and errno != ENETUNREACH) or debug){
807
perror_plus("connect");
818
const char *out = mandos_protocol_version;
821
size_t out_size = strlen(out);
822
ret = (int)TEMP_FAILURE_RETRY(write(tcp_sd, out + written,
823
out_size - written));
826
perror_plus("write");
830
written += (size_t)ret;
831
if(written < out_size){
834
if(out == mandos_protocol_version){
849
fprintf_plus(stderr, "Establishing TLS session with %s\n", ip);
857
/* This casting via intptr_t is to eliminate warning about casting
858
an int to a pointer type. This is exactly how the GnuTLS Guile
859
function "set-session-transport-fd!" does it. */
860
gnutls_transport_set_ptr(session,
861
(gnutls_transport_ptr_t)(intptr_t)tcp_sd);
869
ret = gnutls_handshake(session);
874
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
876
if(ret != GNUTLS_E_SUCCESS){
878
fprintf_plus(stderr, "*** GnuTLS Handshake failed ***\n");
885
/* Read OpenPGP packet that contains the wanted password */
888
fprintf_plus(stderr, "Retrieving OpenPGP encrypted password from"
899
buffer_capacity = incbuffer(&buffer, buffer_length,
901
if(buffer_capacity == 0){
903
perror_plus("incbuffer");
913
sret = gnutls_record_recv(session, buffer+buffer_length,
354
fprintf(stderr, "Bad address: %s\n", ip);
357
to.sin6_port = htons(port);
358
to.sin6_scope_id = if_nametoindex(interface);
361
fprintf(stderr, "Connection to: %s\n", ip);
364
ret = connect(tcp_sd, (struct sockaddr *) &to, sizeof(to));
370
ret = initgnutls (&es);
377
gnutls_transport_set_ptr (es.session, (gnutls_transport_ptr_t) tcp_sd);
380
fprintf(stderr, "Establishing tls session with %s\n", ip);
384
ret = gnutls_handshake (es.session);
386
if (ret != GNUTLS_E_SUCCESS){
387
fprintf(stderr, "\n*** Handshake failed ***\n");
393
//Retrieve gpg packet that contains the wanted password
396
fprintf(stderr, "Retrieving pgp encrypted password from %s\n", ip);
400
if (buffer_length + BUFFER_SIZE > buffer_capacity){
401
buffer = realloc(buffer, buffer_capacity + BUFFER_SIZE);
406
buffer_capacity += BUFFER_SIZE;
409
ret = gnutls_record_recv
410
(es.session, buffer+buffer_length, BUFFER_SIZE);
920
416
case GNUTLS_E_INTERRUPTED:
921
417
case GNUTLS_E_AGAIN:
923
419
case GNUTLS_E_REHANDSHAKE:
925
ret = gnutls_handshake(session);
931
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
933
fprintf_plus(stderr, "*** GnuTLS Re-handshake failed "
420
ret = gnutls_handshake (es.session);
422
fprintf(stderr, "\n*** Handshake failed ***\n");
941
fprintf_plus(stderr, "Unknown error while reading data from"
942
" encrypted session with Mandos server\n");
943
gnutls_bye(session, GNUTLS_SHUT_RDWR);
948
buffer_length += (size_t) sret;
953
fprintf_plus(stderr, "Closing TLS session\n");
962
ret = gnutls_bye(session, GNUTLS_SHUT_RDWR);
967
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
969
if(buffer_length > 0){
970
ssize_t decrypted_buffer_size;
971
decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,
972
&decrypted_buffer, mc);
973
if(decrypted_buffer_size >= 0){
976
while(written < (size_t) decrypted_buffer_size){
982
ret = (int)fwrite(decrypted_buffer + written, 1,
983
(size_t)decrypted_buffer_size - written,
985
if(ret == 0 and ferror(stdout)){
988
fprintf_plus(stderr, "Error writing encrypted data: %s\n",
994
written += (size_t)ret;
1000
/* Shutdown procedure */
1005
free(decrypted_buffer);
1008
ret = (int)TEMP_FAILURE_RETRY(close(tcp_sd));
1014
perror_plus("close");
1016
gnutls_deinit(session);
429
fprintf(stderr, "Unknown error while reading data from encrypted session with mandos server\n");
431
gnutls_bye (es.session, GNUTLS_SHUT_RDWR);
435
buffer_length += ret;
439
if (buffer_length > 0){
440
if ((decrypted_buffer_size = gpg_packet_decrypt(buffer, buffer_length, &decrypted_buffer, CERT_ROOT)) >= 0){
441
fwrite (decrypted_buffer, 1, decrypted_buffer_size, stdout);
442
free(decrypted_buffer);
451
fprintf(stderr, "Closing tls session\n");
455
gnutls_bye (es.session, GNUTLS_SHUT_RDWR);
458
gnutls_deinit (es.session);
459
gnutls_certificate_free_credentials (es.cred);
460
gnutls_global_deinit ();
1026
static void resolve_callback(AvahiSServiceResolver *r,
1027
AvahiIfIndex interface,
1028
AvahiProtocol proto,
1029
AvahiResolverEvent event,
1033
const char *host_name,
1034
const AvahiAddress *address,
1036
AVAHI_GCC_UNUSED AvahiStringList *txt,
1037
AVAHI_GCC_UNUSED AvahiLookupResultFlags
1044
/* Called whenever a service has been resolved successfully or
1053
case AVAHI_RESOLVER_FAILURE:
1054
fprintf_plus(stderr, "(Avahi Resolver) Failed to resolve service "
1055
"'%s' of type '%s' in domain '%s': %s\n", name, type,
1057
avahi_strerror(avahi_server_errno
1058
(((mandos_context*)mc)->server)));
1061
case AVAHI_RESOLVER_FOUND:
1063
char ip[AVAHI_ADDRESS_STR_MAX];
1064
avahi_address_snprint(ip, sizeof(ip), address);
1066
fprintf_plus(stderr, "Mandos server \"%s\" found on %s (%s, %"
1067
PRIdMAX ") on port %" PRIu16 "\n", name,
1068
host_name, ip, (intmax_t)interface, port);
1070
int ret = start_mandos_communication(ip, (in_port_t)port,
1072
avahi_proto_to_af(proto),
1075
avahi_simple_poll_quit(simple_poll);
1077
if(not add_server(ip, (in_port_t)port, interface,
1078
avahi_proto_to_af(proto),
1079
&((mandos_context*)mc)->current_server)){
1080
fprintf_plus(stderr, "Failed to add server \"%s\" to server"
1086
avahi_s_service_resolver_free(r);
1089
static void browse_callback(AvahiSServiceBrowser *b,
1090
AvahiIfIndex interface,
1091
AvahiProtocol protocol,
1092
AvahiBrowserEvent event,
1096
AVAHI_GCC_UNUSED AvahiLookupResultFlags
1103
/* Called whenever a new services becomes available on the LAN or
1104
is removed from the LAN */
1112
case AVAHI_BROWSER_FAILURE:
1114
fprintf_plus(stderr, "(Avahi browser) %s\n",
1115
avahi_strerror(avahi_server_errno
1116
(((mandos_context*)mc)->server)));
1117
avahi_simple_poll_quit(simple_poll);
1120
case AVAHI_BROWSER_NEW:
1121
/* We ignore the returned Avahi resolver object. In the callback
1122
function we free it. If the Avahi server is terminated before
1123
the callback function is called the Avahi server will free the
1126
if(avahi_s_service_resolver_new(((mandos_context*)mc)->server,
1127
interface, protocol, name, type,
1128
domain, protocol, 0,
1129
resolve_callback, mc) == NULL)
1130
fprintf_plus(stderr, "Avahi: Failed to resolve service '%s':"
1132
avahi_strerror(avahi_server_errno
1133
(((mandos_context*)mc)->server)));
1136
case AVAHI_BROWSER_REMOVE:
1139
case AVAHI_BROWSER_ALL_FOR_NOW:
1140
case AVAHI_BROWSER_CACHE_EXHAUSTED:
1142
fprintf_plus(stderr, "No Mandos server found, still"
1149
/* Signal handler that stops main loop after SIGTERM */
1150
static void handle_sigterm(int sig){
1155
signal_received = sig;
1156
int old_errno = errno;
1157
/* set main loop to exit */
1158
if(simple_poll != NULL){
1159
avahi_simple_poll_quit(simple_poll);
1164
bool get_flags(const char *ifname, struct ifreq *ifr){
1168
int s = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1171
perror_plus("socket");
1175
strcpy(ifr->ifr_name, ifname);
1176
ret = ioctl(s, SIOCGIFFLAGS, ifr);
1180
perror_plus("ioctl SIOCGIFFLAGS");
1188
bool good_flags(const char *ifname, const struct ifreq *ifr){
1190
/* Reject the loopback device */
1191
if(ifr->ifr_flags & IFF_LOOPBACK){
1193
fprintf_plus(stderr, "Rejecting loopback interface \"%s\"\n",
1198
/* Accept point-to-point devices only if connect_to is specified */
1199
if(connect_to != NULL and (ifr->ifr_flags & IFF_POINTOPOINT)){
1201
fprintf_plus(stderr, "Accepting point-to-point interface"
1202
" \"%s\"\n", ifname);
1206
/* Otherwise, reject non-broadcast-capable devices */
1207
if(not (ifr->ifr_flags & IFF_BROADCAST)){
1209
fprintf_plus(stderr, "Rejecting non-broadcast interface"
1210
" \"%s\"\n", ifname);
1214
/* Reject non-ARP interfaces (including dummy interfaces) */
1215
if(ifr->ifr_flags & IFF_NOARP){
1217
fprintf_plus(stderr, "Rejecting non-ARP interface \"%s\"\n",
1223
/* Accept this device */
1225
fprintf_plus(stderr, "Interface \"%s\" is good\n", ifname);
1231
* This function determines if a directory entry in /sys/class/net
1232
* corresponds to an acceptable network device.
1233
* (This function is passed to scandir(3) as a filter function.)
1235
int good_interface(const struct dirent *if_entry){
1236
if(if_entry->d_name[0] == '.'){
1241
if(not get_flags(if_entry->d_name, &ifr)){
1243
fprintf_plus(stderr, "Failed to get flags for interface "
1244
"\"%s\"\n", if_entry->d_name);
1249
if(not good_flags(if_entry->d_name, &ifr)){
1256
* This function determines if a network interface is up.
1258
bool interface_is_up(const char *interface){
1260
if(not get_flags(interface, &ifr)){
1262
fprintf_plus(stderr, "Failed to get flags for interface "
1263
"\"%s\"\n", interface);
1268
return (bool)(ifr.ifr_flags & IFF_UP);
1272
* This function determines if a network interface is running
1274
bool interface_is_running(const char *interface){
1276
if(not get_flags(interface, &ifr)){
1278
fprintf_plus(stderr, "Failed to get flags for interface "
1279
"\"%s\"\n", interface);
1284
return (bool)(ifr.ifr_flags & IFF_RUNNING);
1287
int notdotentries(const struct dirent *direntry){
1288
/* Skip "." and ".." */
1289
if(direntry->d_name[0] == '.'
1290
and (direntry->d_name[1] == '\0'
1291
or (direntry->d_name[1] == '.'
1292
and direntry->d_name[2] == '\0'))){
1298
/* Is this directory entry a runnable program? */
1299
int runnable_hook(const struct dirent *direntry){
1304
if((direntry->d_name)[0] == '\0'){
1309
sret = strspn(direntry->d_name, "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
1310
"abcdefghijklmnopqrstuvwxyz"
1313
if((direntry->d_name)[sret] != '\0'){
1314
/* Contains non-allowed characters */
1316
fprintf_plus(stderr, "Ignoring hook \"%s\" with bad name\n",
1322
char *fullname = NULL;
1323
ret = asprintf(&fullname, "%s/%s", hookdir, direntry->d_name);
1325
perror_plus("asprintf");
1329
ret = stat(fullname, &st);
1332
perror_plus("Could not stat hook");
1336
if(not (S_ISREG(st.st_mode))){
1337
/* Not a regular file */
1339
fprintf_plus(stderr, "Ignoring hook \"%s\" - not a file\n",
1344
if(not (st.st_mode & (S_IXUSR | S_IXGRP | S_IXOTH))){
1345
/* Not executable */
1347
fprintf_plus(stderr, "Ignoring hook \"%s\" - not executable\n",
1353
fprintf_plus(stderr, "Hook \"%s\" is acceptable\n",
1359
int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,
1360
mandos_context *mc){
1362
struct timespec now;
1363
struct timespec waited_time;
1364
intmax_t block_time;
1367
if(mc->current_server == NULL){
1369
fprintf_plus(stderr, "Wait until first server is found."
1372
ret = avahi_simple_poll_iterate(s, -1);
1375
fprintf_plus(stderr, "Check current_server if we should run"
1378
/* the current time */
1379
ret = clock_gettime(CLOCK_MONOTONIC, &now);
1381
perror_plus("clock_gettime");
1384
/* Calculating in ms how long time between now and server
1385
who we visted longest time ago. Now - last seen. */
1386
waited_time.tv_sec = (now.tv_sec
1387
- mc->current_server->last_seen.tv_sec);
1388
waited_time.tv_nsec = (now.tv_nsec
1389
- mc->current_server->last_seen.tv_nsec);
1390
/* total time is 10s/10,000ms.
1391
Converting to s from ms by dividing by 1,000,
1392
and ns to ms by dividing by 1,000,000. */
1393
block_time = ((retry_interval
1394
- ((intmax_t)waited_time.tv_sec * 1000))
1395
- ((intmax_t)waited_time.tv_nsec / 1000000));
1398
fprintf_plus(stderr, "Blocking for %" PRIdMAX " ms\n",
1402
if(block_time <= 0){
1403
ret = start_mandos_communication(mc->current_server->ip,
1404
mc->current_server->port,
1405
mc->current_server->if_index,
1406
mc->current_server->af, mc);
1408
avahi_simple_poll_quit(s);
1411
ret = clock_gettime(CLOCK_MONOTONIC,
1412
&mc->current_server->last_seen);
1414
perror_plus("clock_gettime");
1417
mc->current_server = mc->current_server->next;
1418
block_time = 0; /* Call avahi to find new Mandos
1419
servers, but don't block */
1422
ret = avahi_simple_poll_iterate(s, (int)block_time);
1425
if (ret > 0 or errno != EINTR){
1426
return (ret != 1) ? ret : 0;
1432
/* Set effective uid to 0, return errno */
1433
error_t raise_privileges(void){
1434
error_t old_errno = errno;
1435
error_t ret_errno = 0;
1436
if(seteuid(0) == -1){
1438
perror_plus("seteuid");
1444
/* Set effective and real user ID to 0. Return errno. */
1445
error_t raise_privileges_permanently(void){
1446
error_t old_errno = errno;
1447
error_t ret_errno = raise_privileges();
1452
if(setuid(0) == -1){
1454
perror_plus("seteuid");
1460
/* Set effective user ID to unprivileged saved user ID */
1461
error_t lower_privileges(void){
1462
error_t old_errno = errno;
1463
error_t ret_errno = 0;
1464
if(seteuid(uid) == -1){
1466
perror_plus("seteuid");
1472
/* Lower privileges permanently */
1473
error_t lower_privileges_permanently(void){
1474
error_t old_errno = errno;
1475
error_t ret_errno = 0;
1476
if(setuid(uid) == -1){
1478
perror_plus("setuid");
1484
bool run_network_hooks(const char *mode, const char *interface,
1486
struct dirent **direntries;
1487
struct dirent *direntry;
1489
int numhooks = scandir(hookdir, &direntries, runnable_hook,
1492
if(errno == ENOENT){
1494
fprintf_plus(stderr, "Network hook directory \"%s\" not"
1495
" found\n", hookdir);
1498
perror_plus("scandir");
1501
int devnull = open("/dev/null", O_RDONLY);
1502
for(int i = 0; i < numhooks; i++){
1503
direntry = direntries[i];
1504
char *fullname = NULL;
1505
ret = asprintf(&fullname, "%s/%s", hookdir, direntry->d_name);
1507
perror_plus("asprintf");
1511
fprintf_plus(stderr, "Running network hook \"%s\"\n",
1514
pid_t hook_pid = fork();
1517
/* Raise privileges */
1518
raise_privileges_permanently();
1523
perror_plus("setgid");
1525
/* Reset supplementary groups */
1527
ret = setgroups(0, NULL);
1529
perror_plus("setgroups");
1531
dup2(devnull, STDIN_FILENO);
1533
dup2(STDERR_FILENO, STDOUT_FILENO);
1534
ret = setenv("MANDOSNETHOOKDIR", hookdir, 1);
1536
perror_plus("setenv");
1539
ret = setenv("DEVICE", interface, 1);
1541
perror_plus("setenv");
1544
ret = setenv("VERBOSITY", debug ? "1" : "0", 1);
1546
perror_plus("setenv");
1549
ret = setenv("MODE", mode, 1);
1551
perror_plus("setenv");
1555
ret = asprintf(&delaystring, "%f", delay);
1557
perror_plus("asprintf");
1560
ret = setenv("DELAY", delaystring, 1);
1563
perror_plus("setenv");
1567
if(connect_to != NULL){
1568
ret = setenv("CONNECT", connect_to, 1);
1570
perror_plus("setenv");
1574
if(execl(fullname, direntry->d_name, mode, NULL) == -1){
1575
perror_plus("execl");
1576
_exit(EXIT_FAILURE);
1580
if(TEMP_FAILURE_RETRY(waitpid(hook_pid, &status, 0)) == -1){
1581
perror_plus("waitpid");
1585
if(WIFEXITED(status)){
1586
if(WEXITSTATUS(status) != 0){
1587
fprintf_plus(stderr, "Warning: network hook \"%s\" exited"
1588
" with status %d\n", direntry->d_name,
1589
WEXITSTATUS(status));
1593
} else if(WIFSIGNALED(status)){
1594
fprintf_plus(stderr, "Warning: network hook \"%s\" died by"
1595
" signal %d\n", direntry->d_name,
1600
fprintf_plus(stderr, "Warning: network hook \"%s\""
1601
" crashed\n", direntry->d_name);
1608
fprintf_plus(stderr, "Network hook \"%s\" ran successfully\n",
1617
error_t bring_up_interface(const char *const interface,
1620
error_t old_errno = errno;
1621
error_t ret_errno = 0;
1622
int ret, ret_setflags;
1623
struct ifreq network;
1624
unsigned int if_index = if_nametoindex(interface);
1626
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
1636
if(not interface_is_up(interface)){
1637
if(not get_flags(interface, &network) and debug){
1639
fprintf_plus(stderr, "Failed to get flags for interface "
1640
"\"%s\"\n", interface);
1643
network.ifr_flags |= IFF_UP;
1645
sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1648
perror_plus("socket");
1660
fprintf_plus(stderr, "Bringing up interface \"%s\"\n",
1664
/* Raise priviliges */
1668
/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO
1669
messages about the network interface to mess up the prompt */
1670
int ret_linux = klogctl(8, NULL, 5);
1671
bool restore_loglevel = true;
1672
if(ret_linux == -1){
1673
restore_loglevel = false;
1674
perror_plus("klogctl");
1676
#endif /* __linux__ */
1677
ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
1680
if(restore_loglevel){
1681
ret_linux = klogctl(7, NULL, 0);
1682
if(ret_linux == -1){
1683
perror_plus("klogctl");
1686
#endif /* __linux__ */
1688
/* Lower privileges */
1691
/* Close the socket */
1692
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1694
perror_plus("close");
1697
if(ret_setflags == -1){
1699
perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");
1704
fprintf_plus(stderr, "Interface \"%s\" is already up; good\n",
1708
/* Sleep checking until interface is running.
1709
Check every 0.25s, up to total time of delay */
1710
for(int i=0; i < delay * 4; i++){
1711
if(interface_is_running(interface)){
1714
struct timespec sleeptime = { .tv_nsec = 250000000 };
1715
ret = nanosleep(&sleeptime, NULL);
1716
if(ret == -1 and errno != EINTR){
1717
perror_plus("nanosleep");
1725
error_t take_down_interface(const char *const interface){
1727
error_t old_errno = errno;
1728
error_t ret_errno = 0;
1729
int ret, ret_setflags;
1730
struct ifreq network;
1731
unsigned int if_index = if_nametoindex(interface);
1733
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
1737
if(interface_is_up(interface)){
1738
if(not get_flags(interface, &network) and debug){
1740
fprintf_plus(stderr, "Failed to get flags for interface "
1741
"\"%s\"\n", interface);
1744
network.ifr_flags &= ~(short)IFF_UP; /* clear flag */
1746
sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1749
perror_plus("socket");
1755
fprintf_plus(stderr, "Taking down interface \"%s\"\n",
1759
/* Raise priviliges */
1762
ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
1765
/* Lower privileges */
1768
/* Close the socket */
1769
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1771
perror_plus("close");
1774
if(ret_setflags == -1){
1776
perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");
1781
fprintf_plus(stderr, "Interface \"%s\" is already down; odd\n",
1789
int main(int argc, char *argv[]){
1790
mandos_context mc = { .server = NULL, .dh_bits = 1024,
1791
.priority = "SECURE256:!CTYPE-X.509:"
1792
"+CTYPE-OPENPGP", .current_server = NULL,
1793
.interfaces = NULL, .interfaces_size = 0 };
1794
AvahiSServiceBrowser *sb = NULL;
1799
int exitcode = EXIT_SUCCESS;
1800
char *interfaces_to_take_down = NULL;
1801
size_t interfaces_to_take_down_size = 0;
1802
char tempdir[] = "/tmp/mandosXXXXXX";
1803
bool tempdir_created = false;
1804
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
1805
const char *seckey = PATHDIR "/" SECKEY;
1806
const char *pubkey = PATHDIR "/" PUBKEY;
1807
char *interfaces_hooks = NULL;
1808
size_t interfaces_hooks_size = 0;
1810
bool gnutls_initialized = false;
1811
bool gpgme_initialized = false;
1813
double retry_interval = 10; /* 10s between trying a server and
1814
retrying the same server again */
1816
struct sigaction old_sigterm_action = { .sa_handler = SIG_DFL };
1817
struct sigaction sigterm_action = { .sa_handler = handle_sigterm };
1822
/* Lower any group privileges we might have, just to be safe */
1826
perror_plus("setgid");
1829
/* Lower user privileges (temporarily) */
1833
perror_plus("seteuid");
1841
struct argp_option options[] = {
1842
{ .name = "debug", .key = 128,
1843
.doc = "Debug mode", .group = 3 },
1844
{ .name = "connect", .key = 'c',
1845
.arg = "ADDRESS:PORT",
1846
.doc = "Connect directly to a specific Mandos server",
1848
{ .name = "interface", .key = 'i',
1850
.doc = "Network interface that will be used to search for"
1853
{ .name = "seckey", .key = 's',
1855
.doc = "OpenPGP secret key file base name",
1857
{ .name = "pubkey", .key = 'p',
1859
.doc = "OpenPGP public key file base name",
1861
{ .name = "dh-bits", .key = 129,
1863
.doc = "Bit length of the prime number used in the"
1864
" Diffie-Hellman key exchange",
1866
{ .name = "priority", .key = 130,
1868
.doc = "GnuTLS priority string for the TLS handshake",
1870
{ .name = "delay", .key = 131,
1872
.doc = "Maximum delay to wait for interface startup",
1874
{ .name = "retry", .key = 132,
1876
.doc = "Retry interval used when denied by the Mandos server",
1878
{ .name = "network-hook-dir", .key = 133,
1880
.doc = "Directory where network hooks are located",
1883
* These reproduce what we would get without ARGP_NO_HELP
1885
{ .name = "help", .key = '?',
1886
.doc = "Give this help list", .group = -1 },
1887
{ .name = "usage", .key = -3,
1888
.doc = "Give a short usage message", .group = -1 },
1889
{ .name = "version", .key = 'V',
1890
.doc = "Print program version", .group = -1 },
1894
error_t parse_opt(int key, char *arg,
1895
struct argp_state *state){
1898
case 128: /* --debug */
1901
case 'c': /* --connect */
1904
case 'i': /* --interface */
1905
ret_errno = argz_add_sep(&mc.interfaces, &mc.interfaces_size,
1908
argp_error(state, "%s", strerror(ret_errno));
1911
case 's': /* --seckey */
1914
case 'p': /* --pubkey */
1917
case 129: /* --dh-bits */
1919
tmpmax = strtoimax(arg, &tmp, 10);
1920
if(errno != 0 or tmp == arg or *tmp != '\0'
1921
or tmpmax != (typeof(mc.dh_bits))tmpmax){
1922
argp_error(state, "Bad number of DH bits");
1924
mc.dh_bits = (typeof(mc.dh_bits))tmpmax;
1926
case 130: /* --priority */
1929
case 131: /* --delay */
1931
delay = strtof(arg, &tmp);
1932
if(errno != 0 or tmp == arg or *tmp != '\0'){
1933
argp_error(state, "Bad delay");
1935
case 132: /* --retry */
1937
retry_interval = strtod(arg, &tmp);
1938
if(errno != 0 or tmp == arg or *tmp != '\0'
1939
or (retry_interval * 1000) > INT_MAX
1940
or retry_interval < 0){
1941
argp_error(state, "Bad retry interval");
1944
case 133: /* --network-hook-dir */
1948
* These reproduce what we would get without ARGP_NO_HELP
1950
case '?': /* --help */
1951
argp_state_help(state, state->out_stream,
1952
(ARGP_HELP_STD_HELP | ARGP_HELP_EXIT_ERR)
1953
& ~(unsigned int)ARGP_HELP_EXIT_OK);
1954
case -3: /* --usage */
1955
argp_state_help(state, state->out_stream,
1956
ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);
1957
case 'V': /* --version */
1958
fprintf_plus(state->out_stream, "%s\n", argp_program_version);
1959
exit(argp_err_exit_status);
1962
return ARGP_ERR_UNKNOWN;
1967
struct argp argp = { .options = options, .parser = parse_opt,
1969
.doc = "Mandos client -- Get and decrypt"
1970
" passwords from a Mandos server" };
1971
ret = argp_parse(&argp, argc, argv,
1972
ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);
1979
perror_plus("argp_parse");
1980
exitcode = EX_OSERR;
1983
exitcode = EX_USAGE;
1989
/* Work around Debian bug #633582:
1990
<http://bugs.debian.org/633582> */
1992
/* Re-raise priviliges */
1993
if(raise_privileges() == 0){
1996
if(strcmp(seckey, PATHDIR "/" SECKEY) == 0){
1997
int seckey_fd = open(seckey, O_RDONLY);
1998
if(seckey_fd == -1){
1999
perror_plus("open");
2001
ret = (int)TEMP_FAILURE_RETRY(fstat(seckey_fd, &st));
2003
perror_plus("fstat");
2005
if(S_ISREG(st.st_mode)
2006
and st.st_uid == 0 and st.st_gid == 0){
2007
ret = fchown(seckey_fd, uid, gid);
2009
perror_plus("fchown");
2013
TEMP_FAILURE_RETRY(close(seckey_fd));
2017
if(strcmp(pubkey, PATHDIR "/" PUBKEY) == 0){
2018
int pubkey_fd = open(pubkey, O_RDONLY);
2019
if(pubkey_fd == -1){
2020
perror_plus("open");
2022
ret = (int)TEMP_FAILURE_RETRY(fstat(pubkey_fd, &st));
2024
perror_plus("fstat");
2026
if(S_ISREG(st.st_mode)
2027
and st.st_uid == 0 and st.st_gid == 0){
2028
ret = fchown(pubkey_fd, uid, gid);
2030
perror_plus("fchown");
2034
TEMP_FAILURE_RETRY(close(pubkey_fd));
2038
/* Lower privileges */
2043
/* Remove invalid interface names (except "none") */
2045
char *interface = NULL;
2046
while((interface = argz_next(mc.interfaces, mc.interfaces_size,
2048
if(strcmp(interface, "none") != 0
2049
and if_nametoindex(interface) == 0){
2050
if(interface[0] != '\0'){
2051
fprintf_plus(stderr, "Not using nonexisting interface"
2052
" \"%s\"\n", interface);
2054
argz_delete(&mc.interfaces, &mc.interfaces_size, interface);
2060
/* Run network hooks */
2062
if(mc.interfaces != NULL){
2063
interfaces_hooks = malloc(mc.interfaces_size);
2064
if(interfaces_hooks == NULL){
2065
perror_plus("malloc");
2068
memcpy(interfaces_hooks, mc.interfaces, mc.interfaces_size);
2069
interfaces_hooks_size = mc.interfaces_size;
2070
argz_stringify(interfaces_hooks, interfaces_hooks_size,
2073
if(not run_network_hooks("start", interfaces_hooks != NULL ?
2074
interfaces_hooks : "", delay)){
2080
avahi_set_log_function(empty_log);
2083
/* Initialize Avahi early so avahi_simple_poll_quit() can be called
2084
from the signal handler */
2085
/* Initialize the pseudo-RNG for Avahi */
2086
srand((unsigned int) time(NULL));
2087
simple_poll = avahi_simple_poll_new();
2088
if(simple_poll == NULL){
2089
fprintf_plus(stderr,
2090
"Avahi: Failed to create simple poll object.\n");
2091
exitcode = EX_UNAVAILABLE;
2095
sigemptyset(&sigterm_action.sa_mask);
2096
ret = sigaddset(&sigterm_action.sa_mask, SIGINT);
2098
perror_plus("sigaddset");
2099
exitcode = EX_OSERR;
2102
ret = sigaddset(&sigterm_action.sa_mask, SIGHUP);
2104
perror_plus("sigaddset");
2105
exitcode = EX_OSERR;
2108
ret = sigaddset(&sigterm_action.sa_mask, SIGTERM);
2110
perror_plus("sigaddset");
2111
exitcode = EX_OSERR;
2114
/* Need to check if the handler is SIG_IGN before handling:
2115
| [[info:libc:Initial Signal Actions]] |
2116
| [[info:libc:Basic Signal Handling]] |
2118
ret = sigaction(SIGINT, NULL, &old_sigterm_action);
2120
perror_plus("sigaction");
2123
if(old_sigterm_action.sa_handler != SIG_IGN){
2124
ret = sigaction(SIGINT, &sigterm_action, NULL);
2126
perror_plus("sigaction");
2127
exitcode = EX_OSERR;
2131
ret = sigaction(SIGHUP, NULL, &old_sigterm_action);
2133
perror_plus("sigaction");
2136
if(old_sigterm_action.sa_handler != SIG_IGN){
2137
ret = sigaction(SIGHUP, &sigterm_action, NULL);
2139
perror_plus("sigaction");
2140
exitcode = EX_OSERR;
2144
ret = sigaction(SIGTERM, NULL, &old_sigterm_action);
2146
perror_plus("sigaction");
2149
if(old_sigterm_action.sa_handler != SIG_IGN){
2150
ret = sigaction(SIGTERM, &sigterm_action, NULL);
2152
perror_plus("sigaction");
2153
exitcode = EX_OSERR;
2158
/* If no interfaces were specified, make a list */
2159
if(mc.interfaces == NULL){
2160
struct dirent **direntries;
2161
/* Look for any good interfaces */
2162
ret = scandir(sys_class_net, &direntries, good_interface,
2165
/* Add all found interfaces to interfaces list */
2166
for(int i = 0; i < ret; ++i){
2167
ret_errno = argz_add(&mc.interfaces, &mc.interfaces_size,
2168
direntries[i]->d_name);
2170
perror_plus("argz_add");
2174
fprintf_plus(stderr, "Will use interface \"%s\"\n",
2175
direntries[i]->d_name);
2181
fprintf_plus(stderr, "Could not find a network interface\n");
2182
exitcode = EXIT_FAILURE;
2187
/* Bring up interfaces which are down, and remove any "none"s */
2189
char *interface = NULL;
2190
while((interface = argz_next(mc.interfaces, mc.interfaces_size,
2192
/* If interface name is "none", stop bringing up interfaces.
2193
Also remove all instances of "none" from the list */
2194
if(strcmp(interface, "none") == 0){
2195
argz_delete(&mc.interfaces, &mc.interfaces_size,
2198
while((interface = argz_next(mc.interfaces,
2199
mc.interfaces_size, interface))){
2200
if(strcmp(interface, "none") == 0){
2201
argz_delete(&mc.interfaces, &mc.interfaces_size,
2208
bool interface_was_up = interface_is_up(interface);
2209
ret = bring_up_interface(interface, delay);
2210
if(not interface_was_up){
2213
perror_plus("Failed to bring up interface");
2215
ret_errno = argz_add(&interfaces_to_take_down,
2216
&interfaces_to_take_down_size,
2221
if(debug and (interfaces_to_take_down == NULL)){
2222
fprintf_plus(stderr, "No interfaces were brought up\n");
2226
/* If we only got one interface, explicitly use only that one */
2227
if(argz_count(mc.interfaces, mc.interfaces_size) == 1){
2229
fprintf_plus(stderr, "Using only interface \"%s\"\n",
2232
if_index = (AvahiIfIndex)if_nametoindex(mc.interfaces);
2239
ret = init_gnutls_global(pubkey, seckey, &mc);
2241
fprintf_plus(stderr, "init_gnutls_global failed\n");
2242
exitcode = EX_UNAVAILABLE;
2245
gnutls_initialized = true;
2252
if(mkdtemp(tempdir) == NULL){
2253
perror_plus("mkdtemp");
2256
tempdir_created = true;
2262
if(not init_gpgme(pubkey, seckey, tempdir, &mc)){
2263
fprintf_plus(stderr, "init_gpgme failed\n");
2264
exitcode = EX_UNAVAILABLE;
2267
gpgme_initialized = true;
2274
if(connect_to != NULL){
2275
/* Connect directly, do not use Zeroconf */
2276
/* (Mainly meant for debugging) */
2277
char *address = strrchr(connect_to, ':');
2279
if(address == NULL){
2280
fprintf_plus(stderr, "No colon in address\n");
2281
exitcode = EX_USAGE;
2291
tmpmax = strtoimax(address+1, &tmp, 10);
2292
if(errno != 0 or tmp == address+1 or *tmp != '\0'
2293
or tmpmax != (in_port_t)tmpmax){
2294
fprintf_plus(stderr, "Bad port number\n");
2295
exitcode = EX_USAGE;
2303
port = (in_port_t)tmpmax;
2305
/* Colon in address indicates IPv6 */
2307
if(strchr(connect_to, ':') != NULL){
2309
/* Accept [] around IPv6 address - see RFC 5952 */
2310
if(connect_to[0] == '[' and address[-1] == ']')
2318
address = connect_to;
2324
while(not quit_now){
2325
ret = start_mandos_communication(address, port, if_index, af,
2327
if(quit_now or ret == 0){
2331
fprintf_plus(stderr, "Retrying in %d seconds\n",
2332
(int)retry_interval);
2334
sleep((unsigned int)retry_interval);
2338
exitcode = EXIT_SUCCESS;
464
static AvahiSimplePoll *simple_poll = NULL;
465
static AvahiServer *server = NULL;
467
static void resolve_callback(
468
AvahiSServiceResolver *r,
469
AVAHI_GCC_UNUSED AvahiIfIndex interface,
470
AVAHI_GCC_UNUSED AvahiProtocol protocol,
471
AvahiResolverEvent event,
475
const char *host_name,
476
const AvahiAddress *address,
478
AvahiStringList *txt,
479
AvahiLookupResultFlags flags,
480
AVAHI_GCC_UNUSED void* userdata) {
484
/* Called whenever a service has been resolved successfully or timed out */
487
case AVAHI_RESOLVER_FAILURE:
488
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)));
491
case AVAHI_RESOLVER_FOUND: {
492
char ip[AVAHI_ADDRESS_STR_MAX];
493
avahi_address_snprint(ip, sizeof(ip), address);
495
fprintf(stderr, "Mandos server found at %s on port %d\n", ip, port);
497
int ret = start_mandos_communication(ip, port);
505
avahi_s_service_resolver_free(r);
508
static void browse_callback(
509
AvahiSServiceBrowser *b,
510
AvahiIfIndex interface,
511
AvahiProtocol protocol,
512
AvahiBrowserEvent event,
516
AVAHI_GCC_UNUSED AvahiLookupResultFlags flags,
519
AvahiServer *s = userdata;
522
/* Called whenever a new services becomes available on the LAN or is removed from the LAN */
526
case AVAHI_BROWSER_FAILURE:
528
fprintf(stderr, "(Browser) %s\n", avahi_strerror(avahi_server_errno(server)));
529
avahi_simple_poll_quit(simple_poll);
532
case AVAHI_BROWSER_NEW:
533
/* We ignore the returned resolver object. In the callback
534
function we free it. If the server is terminated before
535
the callback function is called the server will free
536
the resolver for us. */
538
if (!(avahi_s_service_resolver_new(s, interface, protocol, name, type, domain, AVAHI_PROTO_INET6, 0, resolve_callback, s)))
539
fprintf(stderr, "Failed to resolve service '%s': %s\n", name, avahi_strerror(avahi_server_errno(s)));
543
case AVAHI_BROWSER_REMOVE:
546
case AVAHI_BROWSER_ALL_FOR_NOW:
547
case AVAHI_BROWSER_CACHE_EXHAUSTED:
552
int main(AVAHI_GCC_UNUSED int argc, AVAHI_GCC_UNUSED char*argv[]) {
2349
553
AvahiServerConfig config;
2350
/* Do not publish any local Zeroconf records */
554
AvahiSServiceBrowser *sb = NULL;
555
const char db[] = "--debug";
558
int returncode = EXIT_SUCCESS;
559
char *basename = rindex(argv[0], '/');
560
if(basename == NULL){
566
char *program_name = malloc(strlen(basename) + sizeof(db));
568
if (program_name == NULL){
573
program_name[0] = '\0';
575
for (int i = 1; i < argc; i++){
576
if (not strncmp(argv[i], db, 5)){
577
strcat(strcat(strcat(program_name, db ), "="), basename);
578
if(not strcmp(argv[i], db) or not strcmp(argv[i], program_name)){
586
avahi_set_log_function(empty_log);
589
/* Initialize the psuedo-RNG */
592
/* Allocate main loop object */
593
if (!(simple_poll = avahi_simple_poll_new())) {
594
fprintf(stderr, "Failed to create simple poll object.\n");
599
/* Do not publish any local records */
2351
600
avahi_server_config_init(&config);
2352
601
config.publish_hinfo = 0;
2353
602
config.publish_addresses = 0;
2354
603
config.publish_workstation = 0;
2355
604
config.publish_domain = 0;
2357
606
/* Allocate a new server */
2358
mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),
2359
&config, NULL, NULL, &ret_errno);
2361
/* Free the Avahi configuration data */
607
server = avahi_server_new(avahi_simple_poll_get(simple_poll), &config, NULL, NULL, &error);
609
/* Free the configuration data */
2362
610
avahi_server_config_free(&config);
2365
/* Check if creating the Avahi server object succeeded */
2366
if(mc.server == NULL){
2367
fprintf_plus(stderr, "Failed to create Avahi server: %s\n",
2368
avahi_strerror(ret_errno));
2369
exitcode = EX_UNAVAILABLE;
2377
/* Create the Avahi service browser */
2378
sb = avahi_s_service_browser_new(mc.server, if_index,
2379
AVAHI_PROTO_UNSPEC, "_mandos._tcp",
2380
NULL, 0, browse_callback,
2383
fprintf_plus(stderr, "Failed to create service browser: %s\n",
2384
avahi_strerror(avahi_server_errno(mc.server)));
2385
exitcode = EX_UNAVAILABLE;
2393
/* Run the main loop */
2396
fprintf_plus(stderr, "Starting Avahi loop search\n");
2399
ret = avahi_loop_with_timeout(simple_poll,
2400
(int)(retry_interval * 1000), &mc);
2402
fprintf_plus(stderr, "avahi_loop_with_timeout exited %s\n",
2403
(ret == 0) ? "successfully" : "with error");
2409
fprintf_plus(stderr, "%s exiting\n", argv[0]);
2412
/* Cleanup things */
2413
free(mc.interfaces);
2416
avahi_s_service_browser_free(sb);
2418
if(mc.server != NULL)
2419
avahi_server_free(mc.server);
2421
if(simple_poll != NULL)
2422
avahi_simple_poll_free(simple_poll);
2424
if(gnutls_initialized){
2425
gnutls_certificate_free_credentials(mc.cred);
2426
gnutls_global_deinit();
2427
gnutls_dh_params_deinit(mc.dh_params);
2430
if(gpgme_initialized){
2431
gpgme_release(mc.ctx);
2434
/* Cleans up the circular linked list of Mandos servers the client
2436
if(mc.current_server != NULL){
2437
mc.current_server->prev->next = NULL;
2438
while(mc.current_server != NULL){
2439
server *next = mc.current_server->next;
2440
free(mc.current_server);
2441
mc.current_server = next;
2445
/* Re-raise priviliges */
2449
/* Run network hooks */
2450
run_network_hooks("stop", interfaces_hooks != NULL ?
2451
interfaces_hooks : "", delay);
2453
/* Take down the network interfaces which were brought up */
2455
char *interface = NULL;
2456
while((interface=argz_next(interfaces_to_take_down,
2457
interfaces_to_take_down_size,
2459
ret_errno = take_down_interface(interface);
2462
perror_plus("Failed to take down interface");
2465
if(debug and (interfaces_to_take_down == NULL)){
2466
fprintf_plus(stderr, "No interfaces needed to be taken"
2471
lower_privileges_permanently();
2474
free(interfaces_to_take_down);
2475
free(interfaces_hooks);
2477
/* Removes the GPGME temp directory and all files inside */
2478
if(tempdir_created){
2479
struct dirent **direntries = NULL;
2480
struct dirent *direntry = NULL;
2481
int numentries = scandir(tempdir, &direntries, notdotentries,
2483
if (numentries > 0){
2484
for(int i = 0; i < numentries; i++){
2485
direntry = direntries[i];
2486
char *fullname = NULL;
2487
ret = asprintf(&fullname, "%s/%s", tempdir,
2490
perror_plus("asprintf");
2493
ret = remove(fullname);
2495
fprintf_plus(stderr, "remove(\"%s\"): %s\n", fullname,
2502
/* need to clean even if 0 because man page doesn't specify */
2504
if (numentries == -1){
2505
perror_plus("scandir");
2507
ret = rmdir(tempdir);
2508
if(ret == -1 and errno != ENOENT){
2509
perror_plus("rmdir");
2514
sigemptyset(&old_sigterm_action.sa_mask);
2515
old_sigterm_action.sa_handler = SIG_DFL;
2516
ret = (int)TEMP_FAILURE_RETRY(sigaction(signal_received,
2517
&old_sigterm_action,
2520
perror_plus("sigaction");
2523
ret = raise(signal_received);
2524
} while(ret != 0 and errno == EINTR);
2526
perror_plus("raise");
2529
TEMP_FAILURE_RETRY(pause());
612
/* Check if creating the server object succeeded */
614
fprintf(stderr, "Failed to create server: %s\n", avahi_strerror(error));
615
returncode = EXIT_FAILURE;
619
/* Create the service browser */
620
if (!(sb = avahi_s_service_browser_new(server, if_nametoindex("eth0"), AVAHI_PROTO_INET6, "_mandos._tcp", NULL, 0, browse_callback, server))) {
621
fprintf(stderr, "Failed to create service browser: %s\n", avahi_strerror(avahi_server_errno(server)));
622
returncode = EXIT_FAILURE;
626
/* Run the main loop */
629
fprintf(stderr, "Starting avahi loop search\n");
632
avahi_simple_poll_loop(simple_poll);
637
fprintf(stderr, "%s exiting\n", argv[0]);
642
avahi_s_service_browser_free(sb);
645
avahi_server_free(server);
648
avahi_simple_poll_free(simple_poll);