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() */
57
#define CERT_ROOT "/conf/conf.d/cryptkeyreq/"
59
#define CERTFILE CERT_ROOT "openpgp-client.txt"
60
#define KEYFILE CERT_ROOT "openpgp-client-key.txt"
127
61
#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
64
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
char *interface = "eth0";
68
gnutls_session_t session;
158
69
gnutls_certificate_credentials_t cred;
159
unsigned int dh_bits;
160
70
gnutls_dh_params_t dh_params;
161
const char *priority;
74
ssize_t gpg_packet_decrypt (char *packet, size_t packet_size, char **new_packet, char *homedir){
75
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){
79
size_t new_packet_capacity = 0;
80
size_t new_packet_length = 0;
253
81
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");
84
fprintf(stderr, "Attempting to decrypt password from gpg packet\n");
296
88
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));
89
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));
91
/* Set GPGME home directory */
92
rc = gpgme_get_engine_info (&engine_info);
93
if (rc != GPG_ERR_NO_ERROR){
94
fprintf(stderr, "bad gpgme_get_engine_info: %s: %s\n",
95
gpgme_strsource(rc), gpgme_strerror(rc));
311
98
while(engine_info != NULL){
312
99
if(engine_info->protocol == GPGME_PROTOCOL_OpenPGP){
313
100
gpgme_set_engine_info(GPGME_PROTOCOL_OpenPGP,
314
engine_info->file_name, tempdir);
101
engine_info->file_name, homedir);
317
104
engine_info = engine_info->next;
319
106
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));
107
fprintf(stderr, "Could not set home dir to %s\n", homedir);
111
/* Create new GPGME data buffer from packet buffer */
112
rc = gpgme_data_new_from_mem(&dh_crypto, packet, packet_size, 0);
113
if (rc != GPG_ERR_NO_ERROR){
114
fprintf(stderr, "bad gpgme_data_new_from_mem: %s: %s\n",
115
gpgme_strsource(rc), gpgme_strerror(rc));
368
119
/* Create new empty GPGME data buffer for the plaintext */
369
120
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;
121
if (rc != GPG_ERR_NO_ERROR){
122
fprintf(stderr, "bad gpgme_data_new: %s: %s\n",
123
gpgme_strsource(rc), gpgme_strerror(rc));
127
/* Create new GPGME "context" */
128
rc = gpgme_new(&ctx);
129
if (rc != GPG_ERR_NO_ERROR){
130
fprintf(stderr, "bad gpgme_new: %s: %s\n",
131
gpgme_strsource(rc), gpgme_strerror(rc));
135
/* Decrypt data from the FILE pointer to the plaintext data buffer */
136
rc = gpgme_op_decrypt(ctx, dh_crypto, dh_plain);
137
if (rc != GPG_ERR_NO_ERROR){
138
fprintf(stderr, "bad gpgme_op_decrypt: %s: %s\n",
139
gpgme_strsource(rc), gpgme_strerror(rc));
144
fprintf(stderr, "decryption of gpg packet succeeded\n");
148
gpgme_decrypt_result_t result;
149
result = gpgme_op_decrypt_result(ctx);
151
fprintf(stderr, "gpgme_op_decrypt_result failed\n");
153
fprintf(stderr, "Unsupported algorithm: %s\n", result->unsupported_algorithm);
154
fprintf(stderr, "Wrong key usage: %d\n", result->wrong_key_usage);
155
if(result->file_name != NULL){
156
fprintf(stderr, "File name: %s\n", result->file_name);
158
gpgme_recipient_t recipient;
159
recipient = result->recipients;
400
161
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
162
fprintf(stderr, "Public key algorithm: %s\n",
163
gpgme_pubkey_algo_name(recipient->pubkey_algo));
164
fprintf(stderr, "Key ID: %s\n", recipient->keyid);
165
fprintf(stderr, "Secret key available: %s\n",
166
recipient->status == GPG_ERR_NO_SECKEY ? "No" : "Yes");
408
167
recipient = recipient->next;
416
fprintf_plus(stderr, "Decryption of OpenPGP data succeeded\n");
173
/* Delete the GPGME FILE pointer cryptotext data buffer */
174
gpgme_data_release(dh_crypto);
419
176
/* 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;
177
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;
181
if (new_packet_length + BUFFER_SIZE > new_packet_capacity){
182
*new_packet = realloc(*new_packet, new_packet_capacity + BUFFER_SIZE);
183
if (*new_packet == NULL){
187
new_packet_capacity += BUFFER_SIZE;
437
ret = gpgme_data_read(dh_plain, *plaintext + plaintext_length,
190
ret = gpgme_data_read(dh_plain, *new_packet + new_packet_length, BUFFER_SIZE);
439
191
/* Print the data, if any */
193
/* 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);
197
perror("gpgme_data_read");
200
new_packet_length += ret;
203
/* FIXME: check characters before printing to screen so to not print
204
terminal control characters */
206
/* fprintf(stderr, "decrypted password is: "); */
207
/* fwrite(*new_packet, 1, new_packet_length, stderr); */
208
/* fprintf(stderr, "\n"); */
465
211
/* Delete the GPGME plaintext data buffer */
466
212
gpgme_data_release(dh_plain);
467
return plaintext_length;
213
return new_packet_length;
470
static const char * safer_gnutls_strerror(int value){
471
const char *ret = gnutls_strerror(value);
216
static const char * safer_gnutls_strerror (int value) {
217
const char *ret = gnutls_strerror (value);
473
219
ret = "(unknown)";
477
/* GnuTLS log function callback */
478
static void debuggnutls(__attribute__((unused)) int level,
480
fprintf_plus(stderr, "GnuTLS: %s", string);
223
void debuggnutls(int level, const char* string){
224
fprintf(stderr, "%s", string);
483
static int init_gnutls_global(const char *pubkeyfilename,
484
const char *seckeyfilename,
227
int initgnutls(encrypted_session *es){
489
fprintf_plus(stderr, "Initializing GnuTLS\n");
232
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));
236
if ((ret = gnutls_global_init ())
237
!= GNUTLS_E_SUCCESS) {
238
fprintf (stderr, "global_init: %s\n", safer_gnutls_strerror(ret));
500
/* "Use a log level over 10 to enable all debugging options."
503
243
gnutls_global_set_log_level(11);
504
244
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();
248
/* openpgp credentials */
249
if ((ret = gnutls_certificate_allocate_credentials (&es->cred))
250
!= GNUTLS_E_SUCCESS) {
251
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",
256
fprintf(stderr, "Attempting to use openpgp certificate %s"
257
" and keyfile %s as gnutls credentials\n", CERTFILE, KEYFILE);
523
260
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);
261
(es->cred, CERTFILE, KEYFILE, GNUTLS_OPENPGP_FMT_BASE64);
262
if (ret != GNUTLS_E_SUCCESS) {
264
(stderr, "Error[%d] while reading the OpenPGP key pair ('%s', '%s')\n",
265
ret, CERTFILE, KEYFILE);
266
fprintf(stdout, "The Error is: %s\n",
267
safer_gnutls_strerror(ret));
271
//Gnutls server initialization
272
if ((ret = gnutls_dh_params_init (&es->dh_params))
273
!= GNUTLS_E_SUCCESS) {
274
fprintf (stderr, "Error in dh parameter initialization: %s\n",
275
safer_gnutls_strerror(ret));
279
if ((ret = gnutls_dh_params_generate2 (es->dh_params, DH_BITS))
280
!= GNUTLS_E_SUCCESS) {
281
fprintf (stderr, "Error in prime generation: %s\n",
282
safer_gnutls_strerror(ret));
286
gnutls_certificate_set_dh_params (es->cred, es->dh_params);
288
// Gnutls session creation
289
if ((ret = gnutls_init (&es->session, GNUTLS_SERVER))
290
!= GNUTLS_E_SUCCESS){
291
fprintf(stderr, "Error in gnutls session initialization: %s\n",
292
safer_gnutls_strerror(ret));
295
if ((ret = gnutls_priority_set_direct (es->session, "NORMAL", &err))
296
!= GNUTLS_E_SUCCESS) {
297
fprintf(stderr, "Syntax error at: %s\n", err);
298
fprintf(stderr, "Gnutls error: %s\n",
299
safer_gnutls_strerror(ret));
303
if ((ret = gnutls_credentials_set
304
(es->session, GNUTLS_CRD_CERTIFICATE, es->cred))
305
!= GNUTLS_E_SUCCESS) {
306
fprintf(stderr, "Error setting a credentials set: %s\n",
307
safer_gnutls_strerror(ret));
611
311
/* ignore client certificate if any. */
612
gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);
312
gnutls_certificate_server_set_request (es->session, GNUTLS_CERT_IGNORE);
614
gnutls_dh_set_prime_bits(*session, mc->dh_bits);
314
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){}
319
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;
321
int start_mandos_communication(char *ip, uint16_t port){
323
struct sockaddr_in6 to;
324
encrypted_session es;
633
325
char *buffer = NULL;
634
char *decrypted_buffer = NULL;
326
char *decrypted_buffer;
635
327
size_t buffer_length = 0;
636
328
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");
329
ssize_t decrypted_buffer_size;
333
fprintf(stderr, "Setting up a tcp connection to %s\n", ip);
336
tcp_sd = socket(PF_INET6, SOCK_STREAM, 0);
343
fprintf(stderr, "Binding to interface %s\n", interface);
346
ret = setsockopt(tcp_sd, SOL_SOCKET, SO_BINDTODEVICE, interface, 5);
348
perror("setsockopt bindtodevice");
352
memset(&to,0,sizeof(to));
353
to.sin6_family = AF_INET6;
354
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);
740
#pragma GCC diagnostic push
741
#pragma GCC diagnostic ignored "-Wstrict-aliasing"
743
if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */
744
(&to.in6.sin6_addr)){ /* -Wstrict-aliasing=2 or lower */
746
#pragma GCC diagnostic pop
748
if(if_index == AVAHI_IF_UNSPEC){
749
fprintf_plus(stderr, "An IPv6 link-local address is"
750
" incomplete without a network interface\n");
754
/* Set the network interface number as scope */
755
to.in6.sin6_scope_id = (uint32_t)if_index;
758
to.in.sin_port = htons(port);
767
if(af == AF_INET6 and if_index != AVAHI_IF_UNSPEC){
768
char interface[IF_NAMESIZE];
769
if(if_indextoname((unsigned int)if_index, interface) == NULL){
770
perror_plus("if_indextoname");
772
fprintf_plus(stderr, "Connection to: %s%%%s, port %" PRIuMAX
773
"\n", ip, interface, (uintmax_t)port);
776
fprintf_plus(stderr, "Connection to: %s, port %" PRIuMAX "\n",
777
ip, (uintmax_t)port);
779
char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?
780
INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";
783
pcret = inet_ntop(af, &(to.in6.sin6_addr), addrstr,
786
pcret = inet_ntop(af, &(to.in.sin_addr), addrstr,
790
perror_plus("inet_ntop");
792
if(strcmp(addrstr, ip) != 0){
793
fprintf_plus(stderr, "Canonical address form: %s\n", addrstr);
804
ret = connect(tcp_sd, &to.in6, sizeof(to));
806
ret = connect(tcp_sd, &to.in, sizeof(to)); /* IPv4 */
809
if ((errno != ECONNREFUSED and errno != ENETUNREACH) or debug){
811
perror_plus("connect");
822
const char *out = mandos_protocol_version;
825
size_t out_size = strlen(out);
826
ret = (int)TEMP_FAILURE_RETRY(write(tcp_sd, out + written,
827
out_size - written));
830
perror_plus("write");
834
written += (size_t)ret;
835
if(written < out_size){
838
if(out == mandos_protocol_version){
853
fprintf_plus(stderr, "Establishing TLS session with %s\n", ip);
861
/* This casting via intptr_t is to eliminate warning about casting
862
an int to a pointer type. This is exactly how the GnuTLS Guile
863
function "set-session-transport-fd!" does it. */
864
gnutls_transport_set_ptr(session,
865
(gnutls_transport_ptr_t)(intptr_t)tcp_sd);
873
ret = gnutls_handshake(session);
878
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
880
if(ret != GNUTLS_E_SUCCESS){
882
fprintf_plus(stderr, "*** GnuTLS Handshake failed ***\n");
889
/* Read OpenPGP packet that contains the wanted password */
892
fprintf_plus(stderr, "Retrieving OpenPGP encrypted password from"
903
buffer_capacity = incbuffer(&buffer, buffer_length,
905
if(buffer_capacity == 0){
907
perror_plus("incbuffer");
917
sret = gnutls_record_recv(session, buffer+buffer_length,
360
fprintf(stderr, "Bad address: %s\n", ip);
363
to.sin6_port = htons(port);
364
to.sin6_scope_id = if_nametoindex(interface);
367
fprintf(stderr, "Connection to: %s\n", ip);
370
ret = connect(tcp_sd, (struct sockaddr *) &to, sizeof(to));
376
ret = initgnutls (&es);
383
gnutls_transport_set_ptr (es.session, (gnutls_transport_ptr_t) tcp_sd);
386
fprintf(stderr, "Establishing tls session with %s\n", ip);
390
ret = gnutls_handshake (es.session);
392
if (ret != GNUTLS_E_SUCCESS){
393
fprintf(stderr, "\n*** Handshake failed ***\n");
399
//Retrieve gpg packet that contains the wanted password
402
fprintf(stderr, "Retrieving pgp encrypted password from %s\n", ip);
406
if (buffer_length + BUFFER_SIZE > buffer_capacity){
407
buffer = realloc(buffer, buffer_capacity + BUFFER_SIZE);
412
buffer_capacity += BUFFER_SIZE;
415
ret = gnutls_record_recv
416
(es.session, buffer+buffer_length, BUFFER_SIZE);
924
422
case GNUTLS_E_INTERRUPTED:
925
423
case GNUTLS_E_AGAIN:
927
425
case GNUTLS_E_REHANDSHAKE:
929
ret = gnutls_handshake(session);
935
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
937
fprintf_plus(stderr, "*** GnuTLS Re-handshake failed "
426
ret = gnutls_handshake (es.session);
428
fprintf(stderr, "\n*** Handshake failed ***\n");
945
fprintf_plus(stderr, "Unknown error while reading data from"
946
" encrypted session with Mandos server\n");
947
gnutls_bye(session, GNUTLS_SHUT_RDWR);
952
buffer_length += (size_t) sret;
957
fprintf_plus(stderr, "Closing TLS session\n");
966
ret = gnutls_bye(session, GNUTLS_SHUT_RDWR);
971
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
973
if(buffer_length > 0){
974
ssize_t decrypted_buffer_size;
975
decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,
976
&decrypted_buffer, mc);
977
if(decrypted_buffer_size >= 0){
980
while(written < (size_t) decrypted_buffer_size){
986
ret = (int)fwrite(decrypted_buffer + written, 1,
987
(size_t)decrypted_buffer_size - written,
989
if(ret == 0 and ferror(stdout)){
992
fprintf_plus(stderr, "Error writing encrypted data: %s\n",
998
written += (size_t)ret;
1004
/* Shutdown procedure */
1009
free(decrypted_buffer);
1012
ret = (int)TEMP_FAILURE_RETRY(close(tcp_sd));
1018
perror_plus("close");
1020
gnutls_deinit(session);
435
fprintf(stderr, "Unknown error while reading data from encrypted session with mandos server\n");
437
gnutls_bye (es.session, GNUTLS_SHUT_RDWR);
441
buffer_length += ret;
445
if (buffer_length > 0){
446
if ((decrypted_buffer_size = gpg_packet_decrypt(buffer, buffer_length, &decrypted_buffer, CERT_ROOT)) >= 0){
447
fwrite (decrypted_buffer, 1, decrypted_buffer_size, stdout);
448
free(decrypted_buffer);
457
fprintf(stderr, "Closing tls session\n");
461
gnutls_bye (es.session, GNUTLS_SHUT_RDWR);
464
gnutls_deinit (es.session);
465
gnutls_certificate_free_credentials (es.cred);
466
gnutls_global_deinit ();
1030
static void resolve_callback(AvahiSServiceResolver *r,
1031
AvahiIfIndex interface,
1032
AvahiProtocol proto,
1033
AvahiResolverEvent event,
1037
const char *host_name,
1038
const AvahiAddress *address,
1040
AVAHI_GCC_UNUSED AvahiStringList *txt,
1041
AVAHI_GCC_UNUSED AvahiLookupResultFlags
1048
/* Called whenever a service has been resolved successfully or
1057
case AVAHI_RESOLVER_FAILURE:
1058
fprintf_plus(stderr, "(Avahi Resolver) Failed to resolve service "
1059
"'%s' of type '%s' in domain '%s': %s\n", name, type,
1061
avahi_strerror(avahi_server_errno
1062
(((mandos_context*)mc)->server)));
1065
case AVAHI_RESOLVER_FOUND:
1067
char ip[AVAHI_ADDRESS_STR_MAX];
1068
avahi_address_snprint(ip, sizeof(ip), address);
1070
fprintf_plus(stderr, "Mandos server \"%s\" found on %s (%s, %"
1071
PRIdMAX ") on port %" PRIu16 "\n", name,
1072
host_name, ip, (intmax_t)interface, port);
1074
int ret = start_mandos_communication(ip, (in_port_t)port,
1076
avahi_proto_to_af(proto),
1079
avahi_simple_poll_quit(simple_poll);
1081
if(not add_server(ip, (in_port_t)port, interface,
1082
avahi_proto_to_af(proto),
1083
&((mandos_context*)mc)->current_server)){
1084
fprintf_plus(stderr, "Failed to add server \"%s\" to server"
1090
avahi_s_service_resolver_free(r);
1093
static void browse_callback(AvahiSServiceBrowser *b,
1094
AvahiIfIndex interface,
1095
AvahiProtocol protocol,
1096
AvahiBrowserEvent event,
1100
AVAHI_GCC_UNUSED AvahiLookupResultFlags
1107
/* Called whenever a new services becomes available on the LAN or
1108
is removed from the LAN */
1116
case AVAHI_BROWSER_FAILURE:
1118
fprintf_plus(stderr, "(Avahi browser) %s\n",
1119
avahi_strerror(avahi_server_errno
1120
(((mandos_context*)mc)->server)));
1121
avahi_simple_poll_quit(simple_poll);
1124
case AVAHI_BROWSER_NEW:
1125
/* We ignore the returned Avahi resolver object. In the callback
1126
function we free it. If the Avahi server is terminated before
1127
the callback function is called the Avahi server will free the
1130
if(avahi_s_service_resolver_new(((mandos_context*)mc)->server,
1131
interface, protocol, name, type,
1132
domain, protocol, 0,
1133
resolve_callback, mc) == NULL)
1134
fprintf_plus(stderr, "Avahi: Failed to resolve service '%s':"
1136
avahi_strerror(avahi_server_errno
1137
(((mandos_context*)mc)->server)));
1140
case AVAHI_BROWSER_REMOVE:
1143
case AVAHI_BROWSER_ALL_FOR_NOW:
1144
case AVAHI_BROWSER_CACHE_EXHAUSTED:
1146
fprintf_plus(stderr, "No Mandos server found, still"
1153
/* Signal handler that stops main loop after SIGTERM */
1154
static void handle_sigterm(int sig){
1159
signal_received = sig;
1160
int old_errno = errno;
1161
/* set main loop to exit */
1162
if(simple_poll != NULL){
1163
avahi_simple_poll_quit(simple_poll);
1168
bool get_flags(const char *ifname, struct ifreq *ifr){
1172
int s = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1175
perror_plus("socket");
1179
strcpy(ifr->ifr_name, ifname);
1180
ret = ioctl(s, SIOCGIFFLAGS, ifr);
1184
perror_plus("ioctl SIOCGIFFLAGS");
1192
bool good_flags(const char *ifname, const struct ifreq *ifr){
1194
/* Reject the loopback device */
1195
if(ifr->ifr_flags & IFF_LOOPBACK){
1197
fprintf_plus(stderr, "Rejecting loopback interface \"%s\"\n",
1202
/* Accept point-to-point devices only if connect_to is specified */
1203
if(connect_to != NULL and (ifr->ifr_flags & IFF_POINTOPOINT)){
1205
fprintf_plus(stderr, "Accepting point-to-point interface"
1206
" \"%s\"\n", ifname);
1210
/* Otherwise, reject non-broadcast-capable devices */
1211
if(not (ifr->ifr_flags & IFF_BROADCAST)){
1213
fprintf_plus(stderr, "Rejecting non-broadcast interface"
1214
" \"%s\"\n", ifname);
1218
/* Reject non-ARP interfaces (including dummy interfaces) */
1219
if(ifr->ifr_flags & IFF_NOARP){
1221
fprintf_plus(stderr, "Rejecting non-ARP interface \"%s\"\n",
1227
/* Accept this device */
1229
fprintf_plus(stderr, "Interface \"%s\" is good\n", ifname);
1235
* This function determines if a directory entry in /sys/class/net
1236
* corresponds to an acceptable network device.
1237
* (This function is passed to scandir(3) as a filter function.)
1239
int good_interface(const struct dirent *if_entry){
1240
if(if_entry->d_name[0] == '.'){
1245
if(not get_flags(if_entry->d_name, &ifr)){
1247
fprintf_plus(stderr, "Failed to get flags for interface "
1248
"\"%s\"\n", if_entry->d_name);
1253
if(not good_flags(if_entry->d_name, &ifr)){
1260
* This function determines if a network interface is up.
1262
bool interface_is_up(const char *interface){
1264
if(not get_flags(interface, &ifr)){
1266
fprintf_plus(stderr, "Failed to get flags for interface "
1267
"\"%s\"\n", interface);
1272
return (bool)(ifr.ifr_flags & IFF_UP);
1276
* This function determines if a network interface is running
1278
bool interface_is_running(const char *interface){
1280
if(not get_flags(interface, &ifr)){
1282
fprintf_plus(stderr, "Failed to get flags for interface "
1283
"\"%s\"\n", interface);
1288
return (bool)(ifr.ifr_flags & IFF_RUNNING);
1291
int notdotentries(const struct dirent *direntry){
1292
/* Skip "." and ".." */
1293
if(direntry->d_name[0] == '.'
1294
and (direntry->d_name[1] == '\0'
1295
or (direntry->d_name[1] == '.'
1296
and direntry->d_name[2] == '\0'))){
1302
/* Is this directory entry a runnable program? */
1303
int runnable_hook(const struct dirent *direntry){
1308
if((direntry->d_name)[0] == '\0'){
1313
sret = strspn(direntry->d_name, "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
1314
"abcdefghijklmnopqrstuvwxyz"
1317
if((direntry->d_name)[sret] != '\0'){
1318
/* Contains non-allowed characters */
1320
fprintf_plus(stderr, "Ignoring hook \"%s\" with bad name\n",
1326
char *fullname = NULL;
1327
ret = asprintf(&fullname, "%s/%s", hookdir, direntry->d_name);
1329
perror_plus("asprintf");
1333
ret = stat(fullname, &st);
1336
perror_plus("Could not stat hook");
1340
if(not (S_ISREG(st.st_mode))){
1341
/* Not a regular file */
1343
fprintf_plus(stderr, "Ignoring hook \"%s\" - not a file\n",
1348
if(not (st.st_mode & (S_IXUSR | S_IXGRP | S_IXOTH))){
1349
/* Not executable */
1351
fprintf_plus(stderr, "Ignoring hook \"%s\" - not executable\n",
1357
fprintf_plus(stderr, "Hook \"%s\" is acceptable\n",
1363
int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,
1364
mandos_context *mc){
1366
struct timespec now;
1367
struct timespec waited_time;
1368
intmax_t block_time;
1371
if(mc->current_server == NULL){
1373
fprintf_plus(stderr, "Wait until first server is found."
1376
ret = avahi_simple_poll_iterate(s, -1);
1379
fprintf_plus(stderr, "Check current_server if we should run"
1382
/* the current time */
1383
ret = clock_gettime(CLOCK_MONOTONIC, &now);
1385
perror_plus("clock_gettime");
1388
/* Calculating in ms how long time between now and server
1389
who we visted longest time ago. Now - last seen. */
1390
waited_time.tv_sec = (now.tv_sec
1391
- mc->current_server->last_seen.tv_sec);
1392
waited_time.tv_nsec = (now.tv_nsec
1393
- mc->current_server->last_seen.tv_nsec);
1394
/* total time is 10s/10,000ms.
1395
Converting to s from ms by dividing by 1,000,
1396
and ns to ms by dividing by 1,000,000. */
1397
block_time = ((retry_interval
1398
- ((intmax_t)waited_time.tv_sec * 1000))
1399
- ((intmax_t)waited_time.tv_nsec / 1000000));
1402
fprintf_plus(stderr, "Blocking for %" PRIdMAX " ms\n",
1406
if(block_time <= 0){
1407
ret = start_mandos_communication(mc->current_server->ip,
1408
mc->current_server->port,
1409
mc->current_server->if_index,
1410
mc->current_server->af, mc);
1412
avahi_simple_poll_quit(s);
1415
ret = clock_gettime(CLOCK_MONOTONIC,
1416
&mc->current_server->last_seen);
1418
perror_plus("clock_gettime");
1421
mc->current_server = mc->current_server->next;
1422
block_time = 0; /* Call avahi to find new Mandos
1423
servers, but don't block */
1426
ret = avahi_simple_poll_iterate(s, (int)block_time);
1429
if (ret > 0 or errno != EINTR){
1430
return (ret != 1) ? ret : 0;
1436
/* Set effective uid to 0, return errno */
1437
error_t raise_privileges(void){
1438
error_t old_errno = errno;
1439
error_t ret_errno = 0;
1440
if(seteuid(0) == -1){
1442
perror_plus("seteuid");
1448
/* Set effective and real user ID to 0. Return errno. */
1449
error_t raise_privileges_permanently(void){
1450
error_t old_errno = errno;
1451
error_t ret_errno = raise_privileges();
1456
if(setuid(0) == -1){
1458
perror_plus("seteuid");
1464
/* Set effective user ID to unprivileged saved user ID */
1465
error_t lower_privileges(void){
1466
error_t old_errno = errno;
1467
error_t ret_errno = 0;
1468
if(seteuid(uid) == -1){
1470
perror_plus("seteuid");
1476
/* Lower privileges permanently */
1477
error_t lower_privileges_permanently(void){
1478
error_t old_errno = errno;
1479
error_t ret_errno = 0;
1480
if(setuid(uid) == -1){
1482
perror_plus("setuid");
1488
bool run_network_hooks(const char *mode, const char *interface,
1490
struct dirent **direntries;
1491
struct dirent *direntry;
1493
int numhooks = scandir(hookdir, &direntries, runnable_hook,
1496
if(errno == ENOENT){
1498
fprintf_plus(stderr, "Network hook directory \"%s\" not"
1499
" found\n", hookdir);
1502
perror_plus("scandir");
1505
int devnull = open("/dev/null", O_RDONLY);
1506
for(int i = 0; i < numhooks; i++){
1507
direntry = direntries[i];
1508
char *fullname = NULL;
1509
ret = asprintf(&fullname, "%s/%s", hookdir, direntry->d_name);
1511
perror_plus("asprintf");
1515
fprintf_plus(stderr, "Running network hook \"%s\"\n",
1518
pid_t hook_pid = fork();
1521
/* Raise privileges */
1522
raise_privileges_permanently();
1527
perror_plus("setgid");
1529
/* Reset supplementary groups */
1531
ret = setgroups(0, NULL);
1533
perror_plus("setgroups");
1535
dup2(devnull, STDIN_FILENO);
1537
dup2(STDERR_FILENO, STDOUT_FILENO);
1538
ret = setenv("MANDOSNETHOOKDIR", hookdir, 1);
1540
perror_plus("setenv");
1543
ret = setenv("DEVICE", interface, 1);
1545
perror_plus("setenv");
1548
ret = setenv("VERBOSITY", debug ? "1" : "0", 1);
1550
perror_plus("setenv");
1553
ret = setenv("MODE", mode, 1);
1555
perror_plus("setenv");
1559
ret = asprintf(&delaystring, "%f", delay);
1561
perror_plus("asprintf");
1564
ret = setenv("DELAY", delaystring, 1);
1567
perror_plus("setenv");
1571
if(connect_to != NULL){
1572
ret = setenv("CONNECT", connect_to, 1);
1574
perror_plus("setenv");
1578
if(execl(fullname, direntry->d_name, mode, NULL) == -1){
1579
perror_plus("execl");
1580
_exit(EXIT_FAILURE);
1584
if(TEMP_FAILURE_RETRY(waitpid(hook_pid, &status, 0)) == -1){
1585
perror_plus("waitpid");
1589
if(WIFEXITED(status)){
1590
if(WEXITSTATUS(status) != 0){
1591
fprintf_plus(stderr, "Warning: network hook \"%s\" exited"
1592
" with status %d\n", direntry->d_name,
1593
WEXITSTATUS(status));
1597
} else if(WIFSIGNALED(status)){
1598
fprintf_plus(stderr, "Warning: network hook \"%s\" died by"
1599
" signal %d\n", direntry->d_name,
1604
fprintf_plus(stderr, "Warning: network hook \"%s\""
1605
" crashed\n", direntry->d_name);
1612
fprintf_plus(stderr, "Network hook \"%s\" ran successfully\n",
1621
error_t bring_up_interface(const char *const interface,
1624
error_t old_errno = errno;
1625
error_t ret_errno = 0;
1626
int ret, ret_setflags;
1627
struct ifreq network;
1628
unsigned int if_index = if_nametoindex(interface);
1630
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
1640
if(not interface_is_up(interface)){
1641
if(not get_flags(interface, &network) and debug){
1643
fprintf_plus(stderr, "Failed to get flags for interface "
1644
"\"%s\"\n", interface);
1647
network.ifr_flags |= IFF_UP;
1649
sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1652
perror_plus("socket");
1664
fprintf_plus(stderr, "Bringing up interface \"%s\"\n",
1668
/* Raise priviliges */
1672
/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO
1673
messages about the network interface to mess up the prompt */
1674
int ret_linux = klogctl(8, NULL, 5);
1675
bool restore_loglevel = true;
1676
if(ret_linux == -1){
1677
restore_loglevel = false;
1678
perror_plus("klogctl");
1680
#endif /* __linux__ */
1681
ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
1684
if(restore_loglevel){
1685
ret_linux = klogctl(7, NULL, 0);
1686
if(ret_linux == -1){
1687
perror_plus("klogctl");
1690
#endif /* __linux__ */
1692
/* Lower privileges */
1695
/* Close the socket */
1696
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1698
perror_plus("close");
1701
if(ret_setflags == -1){
1703
perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");
1708
fprintf_plus(stderr, "Interface \"%s\" is already up; good\n",
1712
/* Sleep checking until interface is running.
1713
Check every 0.25s, up to total time of delay */
1714
for(int i=0; i < delay * 4; i++){
1715
if(interface_is_running(interface)){
1718
struct timespec sleeptime = { .tv_nsec = 250000000 };
1719
ret = nanosleep(&sleeptime, NULL);
1720
if(ret == -1 and errno != EINTR){
1721
perror_plus("nanosleep");
1729
error_t take_down_interface(const char *const interface){
1731
error_t old_errno = errno;
1732
error_t ret_errno = 0;
1733
int ret, ret_setflags;
1734
struct ifreq network;
1735
unsigned int if_index = if_nametoindex(interface);
1737
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
1741
if(interface_is_up(interface)){
1742
if(not get_flags(interface, &network) and debug){
1744
fprintf_plus(stderr, "Failed to get flags for interface "
1745
"\"%s\"\n", interface);
1748
network.ifr_flags &= ~(short)IFF_UP; /* clear flag */
1750
sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1753
perror_plus("socket");
1759
fprintf_plus(stderr, "Taking down interface \"%s\"\n",
1763
/* Raise priviliges */
1766
ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
1769
/* Lower privileges */
1772
/* Close the socket */
1773
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1775
perror_plus("close");
1778
if(ret_setflags == -1){
1780
perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");
1785
fprintf_plus(stderr, "Interface \"%s\" is already down; odd\n",
1793
int main(int argc, char *argv[]){
1794
mandos_context mc = { .server = NULL, .dh_bits = 1024,
1795
.priority = "SECURE256:!CTYPE-X.509:"
1796
"+CTYPE-OPENPGP", .current_server = NULL,
1797
.interfaces = NULL, .interfaces_size = 0 };
1798
AvahiSServiceBrowser *sb = NULL;
1803
int exitcode = EXIT_SUCCESS;
1804
char *interfaces_to_take_down = NULL;
1805
size_t interfaces_to_take_down_size = 0;
1806
char tempdir[] = "/tmp/mandosXXXXXX";
1807
bool tempdir_created = false;
1808
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
1809
const char *seckey = PATHDIR "/" SECKEY;
1810
const char *pubkey = PATHDIR "/" PUBKEY;
1811
char *interfaces_hooks = NULL;
1812
size_t interfaces_hooks_size = 0;
1814
bool gnutls_initialized = false;
1815
bool gpgme_initialized = false;
1817
double retry_interval = 10; /* 10s between trying a server and
1818
retrying the same server again */
1820
struct sigaction old_sigterm_action = { .sa_handler = SIG_DFL };
1821
struct sigaction sigterm_action = { .sa_handler = handle_sigterm };
1826
/* Lower any group privileges we might have, just to be safe */
1830
perror_plus("setgid");
1833
/* Lower user privileges (temporarily) */
1837
perror_plus("seteuid");
1845
struct argp_option options[] = {
1846
{ .name = "debug", .key = 128,
1847
.doc = "Debug mode", .group = 3 },
1848
{ .name = "connect", .key = 'c',
1849
.arg = "ADDRESS:PORT",
1850
.doc = "Connect directly to a specific Mandos server",
1852
{ .name = "interface", .key = 'i',
1854
.doc = "Network interface that will be used to search for"
1857
{ .name = "seckey", .key = 's',
1859
.doc = "OpenPGP secret key file base name",
1861
{ .name = "pubkey", .key = 'p',
1863
.doc = "OpenPGP public key file base name",
1865
{ .name = "dh-bits", .key = 129,
1867
.doc = "Bit length of the prime number used in the"
1868
" Diffie-Hellman key exchange",
1870
{ .name = "priority", .key = 130,
1872
.doc = "GnuTLS priority string for the TLS handshake",
1874
{ .name = "delay", .key = 131,
1876
.doc = "Maximum delay to wait for interface startup",
1878
{ .name = "retry", .key = 132,
1880
.doc = "Retry interval used when denied by the Mandos server",
1882
{ .name = "network-hook-dir", .key = 133,
1884
.doc = "Directory where network hooks are located",
1887
* These reproduce what we would get without ARGP_NO_HELP
1889
{ .name = "help", .key = '?',
1890
.doc = "Give this help list", .group = -1 },
1891
{ .name = "usage", .key = -3,
1892
.doc = "Give a short usage message", .group = -1 },
1893
{ .name = "version", .key = 'V',
1894
.doc = "Print program version", .group = -1 },
1898
error_t parse_opt(int key, char *arg,
1899
struct argp_state *state){
1902
case 128: /* --debug */
1905
case 'c': /* --connect */
1908
case 'i': /* --interface */
1909
ret_errno = argz_add_sep(&mc.interfaces, &mc.interfaces_size,
1912
argp_error(state, "%s", strerror(ret_errno));
1915
case 's': /* --seckey */
1918
case 'p': /* --pubkey */
1921
case 129: /* --dh-bits */
1923
tmpmax = strtoimax(arg, &tmp, 10);
1924
if(errno != 0 or tmp == arg or *tmp != '\0'
1925
or tmpmax != (typeof(mc.dh_bits))tmpmax){
1926
argp_error(state, "Bad number of DH bits");
1928
mc.dh_bits = (typeof(mc.dh_bits))tmpmax;
1930
case 130: /* --priority */
1933
case 131: /* --delay */
1935
delay = strtof(arg, &tmp);
1936
if(errno != 0 or tmp == arg or *tmp != '\0'){
1937
argp_error(state, "Bad delay");
1939
case 132: /* --retry */
1941
retry_interval = strtod(arg, &tmp);
1942
if(errno != 0 or tmp == arg or *tmp != '\0'
1943
or (retry_interval * 1000) > INT_MAX
1944
or retry_interval < 0){
1945
argp_error(state, "Bad retry interval");
1948
case 133: /* --network-hook-dir */
1952
* These reproduce what we would get without ARGP_NO_HELP
1954
case '?': /* --help */
1955
argp_state_help(state, state->out_stream,
1956
(ARGP_HELP_STD_HELP | ARGP_HELP_EXIT_ERR)
1957
& ~(unsigned int)ARGP_HELP_EXIT_OK);
1958
case -3: /* --usage */
1959
argp_state_help(state, state->out_stream,
1960
ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);
1961
case 'V': /* --version */
1962
fprintf_plus(state->out_stream, "%s\n", argp_program_version);
1963
exit(argp_err_exit_status);
1966
return ARGP_ERR_UNKNOWN;
1971
struct argp argp = { .options = options, .parser = parse_opt,
1973
.doc = "Mandos client -- Get and decrypt"
1974
" passwords from a Mandos server" };
1975
ret = argp_parse(&argp, argc, argv,
1976
ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);
1983
perror_plus("argp_parse");
1984
exitcode = EX_OSERR;
1987
exitcode = EX_USAGE;
1993
/* Work around Debian bug #633582:
1994
<http://bugs.debian.org/633582> */
1996
/* Re-raise priviliges */
1997
if(raise_privileges() == 0){
2000
if(strcmp(seckey, PATHDIR "/" SECKEY) == 0){
2001
int seckey_fd = open(seckey, O_RDONLY);
2002
if(seckey_fd == -1){
2003
perror_plus("open");
2005
ret = (int)TEMP_FAILURE_RETRY(fstat(seckey_fd, &st));
2007
perror_plus("fstat");
2009
if(S_ISREG(st.st_mode)
2010
and st.st_uid == 0 and st.st_gid == 0){
2011
ret = fchown(seckey_fd, uid, gid);
2013
perror_plus("fchown");
2017
TEMP_FAILURE_RETRY(close(seckey_fd));
2021
if(strcmp(pubkey, PATHDIR "/" PUBKEY) == 0){
2022
int pubkey_fd = open(pubkey, O_RDONLY);
2023
if(pubkey_fd == -1){
2024
perror_plus("open");
2026
ret = (int)TEMP_FAILURE_RETRY(fstat(pubkey_fd, &st));
2028
perror_plus("fstat");
2030
if(S_ISREG(st.st_mode)
2031
and st.st_uid == 0 and st.st_gid == 0){
2032
ret = fchown(pubkey_fd, uid, gid);
2034
perror_plus("fchown");
2038
TEMP_FAILURE_RETRY(close(pubkey_fd));
2042
/* Lower privileges */
2047
/* Remove invalid interface names (except "none") */
2049
char *interface = NULL;
2050
while((interface = argz_next(mc.interfaces, mc.interfaces_size,
2052
if(strcmp(interface, "none") != 0
2053
and if_nametoindex(interface) == 0){
2054
if(interface[0] != '\0'){
2055
fprintf_plus(stderr, "Not using nonexisting interface"
2056
" \"%s\"\n", interface);
2058
argz_delete(&mc.interfaces, &mc.interfaces_size, interface);
2064
/* Run network hooks */
2066
if(mc.interfaces != NULL){
2067
interfaces_hooks = malloc(mc.interfaces_size);
2068
if(interfaces_hooks == NULL){
2069
perror_plus("malloc");
2072
memcpy(interfaces_hooks, mc.interfaces, mc.interfaces_size);
2073
interfaces_hooks_size = mc.interfaces_size;
2074
argz_stringify(interfaces_hooks, interfaces_hooks_size,
2077
if(not run_network_hooks("start", interfaces_hooks != NULL ?
2078
interfaces_hooks : "", delay)){
2084
avahi_set_log_function(empty_log);
2087
/* Initialize Avahi early so avahi_simple_poll_quit() can be called
2088
from the signal handler */
2089
/* Initialize the pseudo-RNG for Avahi */
2090
srand((unsigned int) time(NULL));
2091
simple_poll = avahi_simple_poll_new();
2092
if(simple_poll == NULL){
2093
fprintf_plus(stderr,
2094
"Avahi: Failed to create simple poll object.\n");
2095
exitcode = EX_UNAVAILABLE;
2099
sigemptyset(&sigterm_action.sa_mask);
2100
ret = sigaddset(&sigterm_action.sa_mask, SIGINT);
2102
perror_plus("sigaddset");
2103
exitcode = EX_OSERR;
2106
ret = sigaddset(&sigterm_action.sa_mask, SIGHUP);
2108
perror_plus("sigaddset");
2109
exitcode = EX_OSERR;
2112
ret = sigaddset(&sigterm_action.sa_mask, SIGTERM);
2114
perror_plus("sigaddset");
2115
exitcode = EX_OSERR;
2118
/* Need to check if the handler is SIG_IGN before handling:
2119
| [[info:libc:Initial Signal Actions]] |
2120
| [[info:libc:Basic Signal Handling]] |
2122
ret = sigaction(SIGINT, NULL, &old_sigterm_action);
2124
perror_plus("sigaction");
2127
if(old_sigterm_action.sa_handler != SIG_IGN){
2128
ret = sigaction(SIGINT, &sigterm_action, NULL);
2130
perror_plus("sigaction");
2131
exitcode = EX_OSERR;
2135
ret = sigaction(SIGHUP, NULL, &old_sigterm_action);
2137
perror_plus("sigaction");
2140
if(old_sigterm_action.sa_handler != SIG_IGN){
2141
ret = sigaction(SIGHUP, &sigterm_action, NULL);
2143
perror_plus("sigaction");
2144
exitcode = EX_OSERR;
2148
ret = sigaction(SIGTERM, NULL, &old_sigterm_action);
2150
perror_plus("sigaction");
2153
if(old_sigterm_action.sa_handler != SIG_IGN){
2154
ret = sigaction(SIGTERM, &sigterm_action, NULL);
2156
perror_plus("sigaction");
2157
exitcode = EX_OSERR;
2162
/* If no interfaces were specified, make a list */
2163
if(mc.interfaces == NULL){
2164
struct dirent **direntries;
2165
/* Look for any good interfaces */
2166
ret = scandir(sys_class_net, &direntries, good_interface,
2169
/* Add all found interfaces to interfaces list */
2170
for(int i = 0; i < ret; ++i){
2171
ret_errno = argz_add(&mc.interfaces, &mc.interfaces_size,
2172
direntries[i]->d_name);
2174
perror_plus("argz_add");
2178
fprintf_plus(stderr, "Will use interface \"%s\"\n",
2179
direntries[i]->d_name);
2185
fprintf_plus(stderr, "Could not find a network interface\n");
2186
exitcode = EXIT_FAILURE;
2191
/* Bring up interfaces which are down, and remove any "none"s */
2193
char *interface = NULL;
2194
while((interface = argz_next(mc.interfaces, mc.interfaces_size,
2196
/* If interface name is "none", stop bringing up interfaces.
2197
Also remove all instances of "none" from the list */
2198
if(strcmp(interface, "none") == 0){
2199
argz_delete(&mc.interfaces, &mc.interfaces_size,
2202
while((interface = argz_next(mc.interfaces,
2203
mc.interfaces_size, interface))){
2204
if(strcmp(interface, "none") == 0){
2205
argz_delete(&mc.interfaces, &mc.interfaces_size,
2212
bool interface_was_up = interface_is_up(interface);
2213
ret = bring_up_interface(interface, delay);
2214
if(not interface_was_up){
2217
perror_plus("Failed to bring up interface");
2219
ret_errno = argz_add(&interfaces_to_take_down,
2220
&interfaces_to_take_down_size,
2225
if(debug and (interfaces_to_take_down == NULL)){
2226
fprintf_plus(stderr, "No interfaces were brought up\n");
2230
/* If we only got one interface, explicitly use only that one */
2231
if(argz_count(mc.interfaces, mc.interfaces_size) == 1){
2233
fprintf_plus(stderr, "Using only interface \"%s\"\n",
2236
if_index = (AvahiIfIndex)if_nametoindex(mc.interfaces);
2243
ret = init_gnutls_global(pubkey, seckey, &mc);
2245
fprintf_plus(stderr, "init_gnutls_global failed\n");
2246
exitcode = EX_UNAVAILABLE;
2249
gnutls_initialized = true;
2256
if(mkdtemp(tempdir) == NULL){
2257
perror_plus("mkdtemp");
2260
tempdir_created = true;
2266
if(not init_gpgme(pubkey, seckey, tempdir, &mc)){
2267
fprintf_plus(stderr, "init_gpgme failed\n");
2268
exitcode = EX_UNAVAILABLE;
2271
gpgme_initialized = true;
2278
if(connect_to != NULL){
2279
/* Connect directly, do not use Zeroconf */
2280
/* (Mainly meant for debugging) */
2281
char *address = strrchr(connect_to, ':');
2283
if(address == NULL){
2284
fprintf_plus(stderr, "No colon in address\n");
2285
exitcode = EX_USAGE;
2295
tmpmax = strtoimax(address+1, &tmp, 10);
2296
if(errno != 0 or tmp == address+1 or *tmp != '\0'
2297
or tmpmax != (in_port_t)tmpmax){
2298
fprintf_plus(stderr, "Bad port number\n");
2299
exitcode = EX_USAGE;
2307
port = (in_port_t)tmpmax;
2309
/* Colon in address indicates IPv6 */
2311
if(strchr(connect_to, ':') != NULL){
2313
/* Accept [] around IPv6 address - see RFC 5952 */
2314
if(connect_to[0] == '[' and address[-1] == ']')
2322
address = connect_to;
2328
while(not quit_now){
2329
ret = start_mandos_communication(address, port, if_index, af,
2331
if(quit_now or ret == 0){
2335
fprintf_plus(stderr, "Retrying in %d seconds\n",
2336
(int)retry_interval);
2338
sleep((unsigned int)retry_interval);
2342
exitcode = EXIT_SUCCESS;
470
static AvahiSimplePoll *simple_poll = NULL;
471
static AvahiServer *server = NULL;
473
static void resolve_callback(
474
AvahiSServiceResolver *r,
475
AVAHI_GCC_UNUSED AvahiIfIndex interface,
476
AVAHI_GCC_UNUSED AvahiProtocol protocol,
477
AvahiResolverEvent event,
481
const char *host_name,
482
const AvahiAddress *address,
484
AvahiStringList *txt,
485
AvahiLookupResultFlags flags,
486
AVAHI_GCC_UNUSED void* userdata) {
490
/* Called whenever a service has been resolved successfully or timed out */
493
case AVAHI_RESOLVER_FAILURE:
494
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)));
497
case AVAHI_RESOLVER_FOUND: {
498
char ip[AVAHI_ADDRESS_STR_MAX];
499
avahi_address_snprint(ip, sizeof(ip), address);
501
fprintf(stderr, "Mandos server found at %s on port %d\n", ip, port);
503
int ret = start_mandos_communication(ip, port);
511
avahi_s_service_resolver_free(r);
514
static void browse_callback(
515
AvahiSServiceBrowser *b,
516
AvahiIfIndex interface,
517
AvahiProtocol protocol,
518
AvahiBrowserEvent event,
522
AVAHI_GCC_UNUSED AvahiLookupResultFlags flags,
525
AvahiServer *s = userdata;
528
/* Called whenever a new services becomes available on the LAN or is removed from the LAN */
532
case AVAHI_BROWSER_FAILURE:
534
fprintf(stderr, "(Browser) %s\n", avahi_strerror(avahi_server_errno(server)));
535
avahi_simple_poll_quit(simple_poll);
538
case AVAHI_BROWSER_NEW:
539
/* We ignore the returned resolver object. In the callback
540
function we free it. If the server is terminated before
541
the callback function is called the server will free
542
the resolver for us. */
544
if (!(avahi_s_service_resolver_new(s, interface, protocol, name, type, domain, AVAHI_PROTO_INET6, 0, resolve_callback, s)))
545
fprintf(stderr, "Failed to resolve service '%s': %s\n", name, avahi_strerror(avahi_server_errno(s)));
549
case AVAHI_BROWSER_REMOVE:
552
case AVAHI_BROWSER_ALL_FOR_NOW:
553
case AVAHI_BROWSER_CACHE_EXHAUSTED:
558
int main(AVAHI_GCC_UNUSED int argc, AVAHI_GCC_UNUSED char*argv[]) {
2353
559
AvahiServerConfig config;
2354
/* Do not publish any local Zeroconf records */
560
AvahiSServiceBrowser *sb = NULL;
563
int returncode = EXIT_SUCCESS;
566
static struct option long_options[] = {
567
{"debug", no_argument, (int *)&debug, 1},
568
{"interface", required_argument, 0, 'i'},
571
int option_index = 0;
572
ret = getopt_long (argc, argv, "i:", long_options, &option_index);
590
avahi_set_log_function(empty_log);
593
/* Initialize the psuedo-RNG */
596
/* Allocate main loop object */
597
if (!(simple_poll = avahi_simple_poll_new())) {
598
fprintf(stderr, "Failed to create simple poll object.\n");
603
/* Do not publish any local records */
2355
604
avahi_server_config_init(&config);
2356
605
config.publish_hinfo = 0;
2357
606
config.publish_addresses = 0;
2358
607
config.publish_workstation = 0;
2359
608
config.publish_domain = 0;
2361
610
/* Allocate a new server */
2362
mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),
2363
&config, NULL, NULL, &ret_errno);
2365
/* Free the Avahi configuration data */
611
server = avahi_server_new(avahi_simple_poll_get(simple_poll), &config, NULL, NULL, &error);
613
/* Free the configuration data */
2366
614
avahi_server_config_free(&config);
2369
/* Check if creating the Avahi server object succeeded */
2370
if(mc.server == NULL){
2371
fprintf_plus(stderr, "Failed to create Avahi server: %s\n",
2372
avahi_strerror(ret_errno));
2373
exitcode = EX_UNAVAILABLE;
2381
/* Create the Avahi service browser */
2382
sb = avahi_s_service_browser_new(mc.server, if_index,
2383
AVAHI_PROTO_UNSPEC, "_mandos._tcp",
2384
NULL, 0, browse_callback,
2387
fprintf_plus(stderr, "Failed to create service browser: %s\n",
2388
avahi_strerror(avahi_server_errno(mc.server)));
2389
exitcode = EX_UNAVAILABLE;
2397
/* Run the main loop */
2400
fprintf_plus(stderr, "Starting Avahi loop search\n");
2403
ret = avahi_loop_with_timeout(simple_poll,
2404
(int)(retry_interval * 1000), &mc);
2406
fprintf_plus(stderr, "avahi_loop_with_timeout exited %s\n",
2407
(ret == 0) ? "successfully" : "with error");
2413
fprintf_plus(stderr, "%s exiting\n", argv[0]);
2416
/* Cleanup things */
2417
free(mc.interfaces);
2420
avahi_s_service_browser_free(sb);
2422
if(mc.server != NULL)
2423
avahi_server_free(mc.server);
2425
if(simple_poll != NULL)
2426
avahi_simple_poll_free(simple_poll);
2428
if(gnutls_initialized){
2429
gnutls_certificate_free_credentials(mc.cred);
2430
gnutls_global_deinit();
2431
gnutls_dh_params_deinit(mc.dh_params);
2434
if(gpgme_initialized){
2435
gpgme_release(mc.ctx);
2438
/* Cleans up the circular linked list of Mandos servers the client
2440
if(mc.current_server != NULL){
2441
mc.current_server->prev->next = NULL;
2442
while(mc.current_server != NULL){
2443
server *next = mc.current_server->next;
2444
free(mc.current_server);
2445
mc.current_server = next;
2449
/* Re-raise priviliges */
2453
/* Run network hooks */
2454
run_network_hooks("stop", interfaces_hooks != NULL ?
2455
interfaces_hooks : "", delay);
2457
/* Take down the network interfaces which were brought up */
2459
char *interface = NULL;
2460
while((interface=argz_next(interfaces_to_take_down,
2461
interfaces_to_take_down_size,
2463
ret_errno = take_down_interface(interface);
2466
perror_plus("Failed to take down interface");
2469
if(debug and (interfaces_to_take_down == NULL)){
2470
fprintf_plus(stderr, "No interfaces needed to be taken"
2475
lower_privileges_permanently();
2478
free(interfaces_to_take_down);
2479
free(interfaces_hooks);
2481
/* Removes the GPGME temp directory and all files inside */
2482
if(tempdir_created){
2483
struct dirent **direntries = NULL;
2484
struct dirent *direntry = NULL;
2485
int numentries = scandir(tempdir, &direntries, notdotentries,
2487
if (numentries > 0){
2488
for(int i = 0; i < numentries; i++){
2489
direntry = direntries[i];
2490
char *fullname = NULL;
2491
ret = asprintf(&fullname, "%s/%s", tempdir,
2494
perror_plus("asprintf");
2497
ret = remove(fullname);
2499
fprintf_plus(stderr, "remove(\"%s\"): %s\n", fullname,
2506
/* need to clean even if 0 because man page doesn't specify */
2508
if (numentries == -1){
2509
perror_plus("scandir");
2511
ret = rmdir(tempdir);
2512
if(ret == -1 and errno != ENOENT){
2513
perror_plus("rmdir");
2518
sigemptyset(&old_sigterm_action.sa_mask);
2519
old_sigterm_action.sa_handler = SIG_DFL;
2520
ret = (int)TEMP_FAILURE_RETRY(sigaction(signal_received,
2521
&old_sigterm_action,
2524
perror_plus("sigaction");
2527
ret = raise(signal_received);
2528
} while(ret != 0 and errno == EINTR);
2530
perror_plus("raise");
2533
TEMP_FAILURE_RETRY(pause());
616
/* Check if creating the server object succeeded */
618
fprintf(stderr, "Failed to create server: %s\n", avahi_strerror(error));
619
returncode = EXIT_FAILURE;
623
/* Create the service browser */
624
if (!(sb = avahi_s_service_browser_new(server, if_nametoindex("eth0"), AVAHI_PROTO_INET6, "_mandos._tcp", NULL, 0, browse_callback, server))) {
625
fprintf(stderr, "Failed to create service browser: %s\n", avahi_strerror(avahi_server_errno(server)));
626
returncode = EXIT_FAILURE;
630
/* Run the main loop */
633
fprintf(stderr, "Starting avahi loop search\n");
636
avahi_simple_poll_loop(simple_poll);
641
fprintf(stderr, "%s exiting\n", argv[0]);
646
avahi_s_service_browser_free(sb);
649
avahi_server_free(server);
652
avahi_simple_poll_free(simple_poll);