107
45
#include <avahi-common/malloc.h>
108
46
#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,
49
#include <sys/types.h> /* socket(), inet_pton() */
50
#include <sys/socket.h> /* socket(), struct sockaddr_in6,
51
struct in6_addr, inet_pton() */
52
#include <gnutls/gnutls.h> /* All GnuTLS stuff */
53
#include <gnutls/openpgp.h> /* GnuTLS with openpgp stuff */
55
#include <unistd.h> /* close() */
56
#include <netinet/in.h>
57
#include <stdbool.h> /* true */
58
#include <string.h> /* memset */
59
#include <arpa/inet.h> /* inet_pton() */
60
#include <iso646.h> /* not */
63
#include <errno.h> /* perror() */
127
69
#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"
72
static const char *certdir = "/conf/conf.d/mandos";
73
static const char *certfile = "openpgp-client.txt";
74
static const char *certkey = "openpgp-client-key.txt";
134
76
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 */
79
gnutls_session_t session;
158
80
gnutls_certificate_credentials_t cred;
159
unsigned int dh_bits;
160
81
gnutls_dh_params_t dh_params;
161
const char *priority;
85
static ssize_t pgp_packet_decrypt (char *packet, size_t packet_size,
88
gpgme_data_t dh_crypto, dh_plain;
163
server *current_server;
166
/* global so signal handler can reach it*/
167
AvahiSimplePoll *simple_poll;
168
mandos_context mc = { .server = NULL, .dh_bits = 1024,
169
.priority = "SECURE256:!CTYPE-X.509:"
170
"+CTYPE-OPENPGP", .current_server = NULL };
172
sig_atomic_t quit_now = 0;
173
int signal_received = 0;
175
/* Function to use when printing errors */
176
void perror_plus(const char *print_text){
178
fprintf(stderr, "Mandos plugin %s: ",
179
program_invocation_short_name);
184
__attribute__((format (gnu_printf, 2, 3)))
185
int fprintf_plus(FILE *stream, const char *format, ...){
187
va_start (ap, format);
189
TEMP_FAILURE_RETRY(fprintf(stream, "Mandos plugin %s: ",
190
program_invocation_short_name));
191
return TEMP_FAILURE_RETRY(vfprintf(stream, format, ap));
195
* Make additional room in "buffer" for at least BUFFER_SIZE more
196
* bytes. "buffer_capacity" is how much is currently allocated,
197
* "buffer_length" is how much is already used.
199
size_t incbuffer(char **buffer, size_t buffer_length,
200
size_t buffer_capacity){
201
if(buffer_length + BUFFER_SIZE > buffer_capacity){
202
*buffer = realloc(*buffer, buffer_capacity + BUFFER_SIZE);
206
buffer_capacity += BUFFER_SIZE;
208
return buffer_capacity;
211
/* Add server to set of servers to retry periodically */
212
bool add_server(const char *ip, in_port_t port, AvahiIfIndex if_index,
215
server *new_server = malloc(sizeof(server));
216
if(new_server == NULL){
217
perror_plus("malloc");
220
*new_server = (server){ .ip = strdup(ip),
222
.if_index = if_index,
224
if(new_server->ip == NULL){
225
perror_plus("strdup");
228
/* Special case of first server */
229
if (mc.current_server == NULL){
230
new_server->next = new_server;
231
new_server->prev = new_server;
232
mc.current_server = new_server;
233
/* Place the new server last in the list */
235
new_server->next = mc.current_server;
236
new_server->prev = mc.current_server->prev;
237
new_server->prev->next = new_server;
238
mc.current_server->prev = new_server;
240
ret = clock_gettime(CLOCK_MONOTONIC, &mc.current_server->last_seen);
242
perror_plus("clock_gettime");
251
static bool init_gpgme(const char *seckey, const char *pubkey,
252
const char *tempdir){
92
ssize_t new_packet_capacity = 0;
93
ssize_t new_packet_length = 0;
254
94
gpgme_engine_info_t engine_info;
257
* Helper function to insert pub and seckey to the engine keyring.
259
bool import_key(const char *filename){
262
gpgme_data_t pgp_data;
264
fd = (int)TEMP_FAILURE_RETRY(open(filename, O_RDONLY));
270
rc = gpgme_data_new_from_fd(&pgp_data, fd);
271
if(rc != GPG_ERR_NO_ERROR){
272
fprintf_plus(stderr, "bad gpgme_data_new_from_fd: %s: %s\n",
273
gpgme_strsource(rc), gpgme_strerror(rc));
277
rc = gpgme_op_import(mc.ctx, pgp_data);
278
if(rc != GPG_ERR_NO_ERROR){
279
fprintf_plus(stderr, "bad gpgme_op_import: %s: %s\n",
280
gpgme_strsource(rc), gpgme_strerror(rc));
284
ret = (int)TEMP_FAILURE_RETRY(close(fd));
286
perror_plus("close");
288
gpgme_data_release(pgp_data);
293
fprintf_plus(stderr, "Initializing GPGME\n");
97
fprintf(stderr, "Trying to decrypt OpenPGP packet\n");
297
101
gpgme_check_version(NULL);
298
102
rc = gpgme_engine_check_version(GPGME_PROTOCOL_OpenPGP);
299
if(rc != GPG_ERR_NO_ERROR){
300
fprintf_plus(stderr, "bad gpgme_engine_check_version: %s: %s\n",
301
gpgme_strsource(rc), gpgme_strerror(rc));
103
if (rc != GPG_ERR_NO_ERROR){
104
fprintf(stderr, "bad gpgme_engine_check_version: %s: %s\n",
105
gpgme_strsource(rc), gpgme_strerror(rc));
305
/* Set GPGME home directory for the OpenPGP engine only */
306
rc = gpgme_get_engine_info(&engine_info);
307
if(rc != GPG_ERR_NO_ERROR){
308
fprintf_plus(stderr, "bad gpgme_get_engine_info: %s: %s\n",
309
gpgme_strsource(rc), gpgme_strerror(rc));
109
/* Set GPGME home directory */
110
rc = gpgme_get_engine_info (&engine_info);
111
if (rc != GPG_ERR_NO_ERROR){
112
fprintf(stderr, "bad gpgme_get_engine_info: %s: %s\n",
113
gpgme_strsource(rc), gpgme_strerror(rc));
312
116
while(engine_info != NULL){
313
117
if(engine_info->protocol == GPGME_PROTOCOL_OpenPGP){
314
118
gpgme_set_engine_info(GPGME_PROTOCOL_OpenPGP,
315
engine_info->file_name, tempdir);
119
engine_info->file_name, homedir);
318
122
engine_info = engine_info->next;
320
124
if(engine_info == NULL){
321
fprintf_plus(stderr, "Could not set GPGME home dir to %s\n",
326
/* Create new GPGME "context" */
327
rc = gpgme_new(&(mc.ctx));
328
if(rc != GPG_ERR_NO_ERROR){
329
fprintf_plus(stderr, "Mandos plugin mandos-client: "
330
"bad gpgme_new: %s: %s\n", gpgme_strsource(rc),
335
if(not import_key(pubkey) or not import_key(seckey)){
343
* Decrypt OpenPGP data.
344
* Returns -1 on error
346
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));
125
fprintf(stderr, "Could not set home dir to %s\n", homedir);
129
/* Create new GPGME data buffer from packet buffer */
130
rc = gpgme_data_new_from_mem(&dh_crypto, packet, packet_size, 0);
131
if (rc != GPG_ERR_NO_ERROR){
132
fprintf(stderr, "bad gpgme_data_new_from_mem: %s: %s\n",
133
gpgme_strsource(rc), gpgme_strerror(rc));
368
137
/* Create new empty GPGME data buffer for the plaintext */
369
138
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;
139
if (rc != GPG_ERR_NO_ERROR){
140
fprintf(stderr, "bad gpgme_data_new: %s: %s\n",
141
gpgme_strsource(rc), gpgme_strerror(rc));
145
/* Create new GPGME "context" */
146
rc = gpgme_new(&ctx);
147
if (rc != GPG_ERR_NO_ERROR){
148
fprintf(stderr, "bad gpgme_new: %s: %s\n",
149
gpgme_strsource(rc), gpgme_strerror(rc));
153
/* Decrypt data from the FILE pointer to the plaintext data
155
rc = gpgme_op_decrypt(ctx, dh_crypto, dh_plain);
156
if (rc != GPG_ERR_NO_ERROR){
157
fprintf(stderr, "bad gpgme_op_decrypt: %s: %s\n",
158
gpgme_strsource(rc), gpgme_strerror(rc));
163
fprintf(stderr, "Decryption of OpenPGP packet succeeded\n");
167
gpgme_decrypt_result_t result;
168
result = gpgme_op_decrypt_result(ctx);
170
fprintf(stderr, "gpgme_op_decrypt_result failed\n");
172
fprintf(stderr, "Unsupported algorithm: %s\n",
173
result->unsupported_algorithm);
174
fprintf(stderr, "Wrong key usage: %d\n",
175
result->wrong_key_usage);
176
if(result->file_name != NULL){
177
fprintf(stderr, "File name: %s\n", result->file_name);
179
gpgme_recipient_t recipient;
180
recipient = result->recipients;
400
182
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
183
fprintf(stderr, "Public key algorithm: %s\n",
184
gpgme_pubkey_algo_name(recipient->pubkey_algo));
185
fprintf(stderr, "Key ID: %s\n", recipient->keyid);
186
fprintf(stderr, "Secret key available: %s\n",
187
recipient->status == GPG_ERR_NO_SECKEY
408
189
recipient = recipient->next;
416
fprintf_plus(stderr, "Decryption of OpenPGP data succeeded\n");
195
/* Delete the GPGME FILE pointer cryptotext data buffer */
196
gpgme_data_release(dh_crypto);
419
198
/* 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;
199
if (gpgme_data_seek(dh_plain, (off_t) 0, SEEK_SET) == -1){
200
perror("pgpme_data_seek");
428
plaintext_capacity = incbuffer(plaintext,
429
(size_t)plaintext_length,
431
if(plaintext_capacity == 0){
432
perror_plus("incbuffer");
433
plaintext_length = -1;
205
if (new_packet_length + BUFFER_SIZE > new_packet_capacity){
206
*new_packet = realloc(*new_packet,
207
(unsigned int)new_packet_capacity
209
if (*new_packet == NULL){
213
new_packet_capacity += BUFFER_SIZE;
437
ret = gpgme_data_read(dh_plain, *plaintext + plaintext_length,
216
ret = gpgme_data_read(dh_plain, *new_packet + new_packet_length,
439
218
/* Print the data, if any */
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);
223
perror("gpgme_data_read");
226
new_packet_length += ret;
229
/* FIXME: check characters before printing to screen so to not print
230
terminal control characters */
232
/* fprintf(stderr, "decrypted password is: "); */
233
/* fwrite(*new_packet, 1, new_packet_length, stderr); */
234
/* fprintf(stderr, "\n"); */
465
237
/* Delete the GPGME plaintext data buffer */
466
238
gpgme_data_release(dh_plain);
467
return plaintext_length;
239
return new_packet_length;
470
static const char * safer_gnutls_strerror(int value){
471
const char *ret = gnutls_strerror(value);
242
static const char * safer_gnutls_strerror (int value) {
243
const char *ret = gnutls_strerror (value);
473
245
ret = "(unknown)";
477
/* GnuTLS log function callback */
478
249
static void debuggnutls(__attribute__((unused)) int level,
479
250
const char* string){
480
fprintf_plus(stderr, "GnuTLS: %s", string);
251
fprintf(stderr, "%s", string);
483
static int init_gnutls_global(const char *pubkeyfilename,
484
const char *seckeyfilename){
254
static int initgnutls(encrypted_session *es){
488
fprintf_plus(stderr, "Initializing GnuTLS\n");
259
fprintf(stderr, "Initializing GnuTLS\n");
491
ret = gnutls_global_init();
492
if(ret != GNUTLS_E_SUCCESS){
493
fprintf_plus(stderr, "GnuTLS global_init: %s\n",
494
safer_gnutls_strerror(ret));
262
if ((ret = gnutls_global_init ())
263
!= GNUTLS_E_SUCCESS) {
264
fprintf (stderr, "global_init: %s\n", safer_gnutls_strerror(ret));
499
/* "Use a log level over 10 to enable all debugging options."
502
269
gnutls_global_set_log_level(11);
503
270
gnutls_global_set_log_function(debuggnutls);
506
/* OpenPGP credentials */
507
ret = gnutls_certificate_allocate_credentials(&mc.cred);
508
if(ret != GNUTLS_E_SUCCESS){
509
fprintf_plus(stderr, "GnuTLS memory error: %s\n",
510
safer_gnutls_strerror(ret));
511
gnutls_global_deinit();
273
/* openpgp credentials */
274
if ((ret = gnutls_certificate_allocate_credentials (&es->cred))
275
!= GNUTLS_E_SUCCESS) {
276
fprintf (stderr, "memory error: %s\n",
277
safer_gnutls_strerror(ret));
516
fprintf_plus(stderr, "Attempting to use OpenPGP public key %s and"
517
" secret key %s as GnuTLS credentials\n",
282
fprintf(stderr, "Attempting to use OpenPGP certificate %s"
283
" and keyfile %s as GnuTLS credentials\n", certfile,
522
287
ret = gnutls_certificate_set_openpgp_key_file
523
(mc.cred, pubkeyfilename, seckeyfilename,
524
GNUTLS_OPENPGP_FMT_BASE64);
525
if(ret != GNUTLS_E_SUCCESS){
527
"Error[%d] while reading the OpenPGP key pair ('%s',"
528
" '%s')\n", ret, pubkeyfilename, seckeyfilename);
529
fprintf_plus(stderr, "The GnuTLS error is: %s\n",
530
safer_gnutls_strerror(ret));
534
/* GnuTLS server initialization */
535
ret = gnutls_dh_params_init(&mc.dh_params);
536
if(ret != GNUTLS_E_SUCCESS){
537
fprintf_plus(stderr, "Error in GnuTLS DH parameter"
538
" initialization: %s\n",
539
safer_gnutls_strerror(ret));
542
ret = gnutls_dh_params_generate2(mc.dh_params, mc.dh_bits);
543
if(ret != GNUTLS_E_SUCCESS){
544
fprintf_plus(stderr, "Error in GnuTLS prime generation: %s\n",
545
safer_gnutls_strerror(ret));
549
gnutls_certificate_set_dh_params(mc.cred, mc.dh_params);
555
gnutls_certificate_free_credentials(mc.cred);
556
gnutls_global_deinit();
557
gnutls_dh_params_deinit(mc.dh_params);
561
static int init_gnutls_session(gnutls_session_t *session){
563
/* GnuTLS session creation */
565
ret = gnutls_init(session, GNUTLS_SERVER);
569
} while(ret == GNUTLS_E_INTERRUPTED or ret == GNUTLS_E_AGAIN);
570
if(ret != GNUTLS_E_SUCCESS){
572
"Error in GnuTLS session initialization: %s\n",
573
safer_gnutls_strerror(ret));
579
ret = gnutls_priority_set_direct(*session, mc.priority, &err);
581
gnutls_deinit(*session);
584
} while(ret == GNUTLS_E_INTERRUPTED or ret == GNUTLS_E_AGAIN);
585
if(ret != GNUTLS_E_SUCCESS){
586
fprintf_plus(stderr, "Syntax error at: %s\n", err);
587
fprintf_plus(stderr, "GnuTLS error: %s\n",
588
safer_gnutls_strerror(ret));
589
gnutls_deinit(*session);
595
ret = gnutls_credentials_set(*session, GNUTLS_CRD_CERTIFICATE,
598
gnutls_deinit(*session);
601
} while(ret == GNUTLS_E_INTERRUPTED or ret == GNUTLS_E_AGAIN);
602
if(ret != GNUTLS_E_SUCCESS){
603
fprintf_plus(stderr, "Error setting GnuTLS credentials: %s\n",
604
safer_gnutls_strerror(ret));
605
gnutls_deinit(*session);
288
(es->cred, certfile, certkey, GNUTLS_OPENPGP_FMT_BASE64);
289
if (ret != GNUTLS_E_SUCCESS) {
291
(stderr, "Error[%d] while reading the OpenPGP key pair ('%s',"
293
ret, certfile, certkey);
294
fprintf(stdout, "The Error is: %s\n",
295
safer_gnutls_strerror(ret));
299
//GnuTLS server initialization
300
if ((ret = gnutls_dh_params_init (&es->dh_params))
301
!= GNUTLS_E_SUCCESS) {
302
fprintf (stderr, "Error in dh parameter initialization: %s\n",
303
safer_gnutls_strerror(ret));
307
if ((ret = gnutls_dh_params_generate2 (es->dh_params, DH_BITS))
308
!= GNUTLS_E_SUCCESS) {
309
fprintf (stderr, "Error in prime generation: %s\n",
310
safer_gnutls_strerror(ret));
314
gnutls_certificate_set_dh_params (es->cred, es->dh_params);
316
// GnuTLS session creation
317
if ((ret = gnutls_init (&es->session, GNUTLS_SERVER))
318
!= GNUTLS_E_SUCCESS){
319
fprintf(stderr, "Error in GnuTLS session initialization: %s\n",
320
safer_gnutls_strerror(ret));
323
if ((ret = gnutls_priority_set_direct (es->session, "NORMAL", &err))
324
!= GNUTLS_E_SUCCESS) {
325
fprintf(stderr, "Syntax error at: %s\n", err);
326
fprintf(stderr, "GnuTLS error: %s\n",
327
safer_gnutls_strerror(ret));
331
if ((ret = gnutls_credentials_set
332
(es->session, GNUTLS_CRD_CERTIFICATE, es->cred))
333
!= GNUTLS_E_SUCCESS) {
334
fprintf(stderr, "Error setting a credentials set: %s\n",
335
safer_gnutls_strerror(ret));
609
339
/* ignore client certificate if any. */
610
gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);
340
gnutls_certificate_server_set_request (es->session,
612
gnutls_dh_set_prime_bits(*session, mc.dh_bits);
343
gnutls_dh_set_prime_bits (es->session, DH_BITS);
617
/* Avahi log function callback */
618
348
static void empty_log(__attribute__((unused)) AvahiLogLevel level,
619
349
__attribute__((unused)) const char *txt){}
621
/* Called when a Mandos server is found */
622
static int start_mandos_communication(const char *ip, in_port_t port,
623
AvahiIfIndex if_index,
625
int ret, tcp_sd = -1;
628
struct sockaddr_in in;
629
struct sockaddr_in6 in6;
351
static int start_mandos_communication(const char *ip, uint16_t port,
352
AvahiIfIndex if_index){
354
struct sockaddr_in6 to;
355
encrypted_session es;
631
356
char *buffer = NULL;
632
char *decrypted_buffer = NULL;
357
char *decrypted_buffer;
633
358
size_t buffer_length = 0;
634
359
size_t buffer_capacity = 0;
637
gnutls_session_t session;
638
int pf; /* Protocol family */
655
fprintf_plus(stderr, "Bad address family: %d\n", af);
660
ret = init_gnutls_session(&session);
666
fprintf_plus(stderr, "Setting up a TCP connection to %s, port %"
667
PRIuMAX "\n", ip, (uintmax_t)port);
670
tcp_sd = socket(pf, SOCK_STREAM, 0);
673
perror_plus("socket");
683
memset(&to, 0, sizeof(to));
685
to.in6.sin6_family = (sa_family_t)af;
686
ret = inet_pton(af, ip, &to.in6.sin6_addr);
688
to.in.sin_family = (sa_family_t)af;
689
ret = inet_pton(af, ip, &to.in.sin_addr);
693
perror_plus("inet_pton");
360
ssize_t decrypted_buffer_size;
363
char interface[IF_NAMESIZE];
366
fprintf(stderr, "Setting up a tcp connection to %s, port %d\n",
370
tcp_sd = socket(PF_INET6, SOCK_STREAM, 0);
376
if(if_indextoname((unsigned int)if_index, interface) == NULL){
378
perror("if_indextoname");
384
fprintf(stderr, "Binding to interface %s\n", interface);
387
memset(&to,0,sizeof(to)); /* Spurious warning */
388
to.sin6_family = AF_INET6;
389
ret = inet_pton(AF_INET6, ip, &to.sin6_addr);
699
fprintf_plus(stderr, "Bad address: %s\n", ip);
704
to.in6.sin6_port = htons(port);
705
if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */
706
(&to.in6.sin6_addr)){ /* -Wstrict-aliasing=2 or lower and
708
if(if_index == AVAHI_IF_UNSPEC){
709
fprintf_plus(stderr, "An IPv6 link-local address is"
710
" incomplete without a network interface\n");
714
/* Set the network interface number as scope */
715
to.in6.sin6_scope_id = (uint32_t)if_index;
718
to.in.sin_port = htons(port); /* Spurious warnings from
720
-Wunreachable-code */
729
if(af == AF_INET6 and if_index != AVAHI_IF_UNSPEC){
730
char interface[IF_NAMESIZE];
731
if(if_indextoname((unsigned int)if_index, interface) == NULL){
732
perror_plus("if_indextoname");
734
fprintf_plus(stderr, "Connection to: %s%%%s, port %" PRIuMAX
735
"\n", ip, interface, (uintmax_t)port);
738
fprintf_plus(stderr, "Connection to: %s, port %" PRIuMAX "\n",
739
ip, (uintmax_t)port);
741
char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?
742
INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";
745
pcret = inet_ntop(af, &(to.in6.sin6_addr), addrstr,
748
pcret = inet_ntop(af, &(to.in.sin_addr), addrstr,
752
perror_plus("inet_ntop");
754
if(strcmp(addrstr, ip) != 0){
755
fprintf_plus(stderr, "Canonical address form: %s\n", addrstr);
766
ret = connect(tcp_sd, &to.in6, sizeof(to));
768
ret = connect(tcp_sd, &to.in, sizeof(to)); /* IPv4 */
771
if ((errno != ECONNREFUSED and errno != ENETUNREACH) or debug){
773
perror_plus("connect");
784
const char *out = mandos_protocol_version;
787
size_t out_size = strlen(out);
788
ret = (int)TEMP_FAILURE_RETRY(write(tcp_sd, out + written,
789
out_size - written));
792
perror_plus("write");
796
written += (size_t)ret;
797
if(written < out_size){
800
if(out == mandos_protocol_version){
815
fprintf_plus(stderr, "Establishing TLS session with %s\n", ip);
823
/* This casting via intptr_t is to eliminate warning about casting
824
an int to a pointer type. This is exactly how the GnuTLS Guile
825
function "set-session-transport-fd!" does it. */
826
gnutls_transport_set_ptr(session,
827
(gnutls_transport_ptr_t)(intptr_t)tcp_sd);
835
ret = gnutls_handshake(session);
840
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
842
if(ret != GNUTLS_E_SUCCESS){
395
fprintf(stderr, "Bad address: %s\n", ip);
398
to.sin6_port = htons(port); /* Spurious warning */
400
to.sin6_scope_id = (uint32_t)if_index;
403
fprintf(stderr, "Connection to: %s, port %d\n", ip, port);
404
/* char addrstr[INET6_ADDRSTRLEN]; */
405
/* if(inet_ntop(to.sin6_family, &(to.sin6_addr), addrstr, */
406
/* sizeof(addrstr)) == NULL){ */
407
/* perror("inet_ntop"); */
409
/* fprintf(stderr, "Really connecting to: %s, port %d\n", */
410
/* addrstr, ntohs(to.sin6_port)); */
414
ret = connect(tcp_sd, (struct sockaddr *) &to, sizeof(to));
420
ret = initgnutls (&es);
426
gnutls_transport_set_ptr (es.session,
427
(gnutls_transport_ptr_t) tcp_sd);
430
fprintf(stderr, "Establishing TLS session with %s\n", ip);
433
ret = gnutls_handshake (es.session);
435
if (ret != GNUTLS_E_SUCCESS){
844
fprintf_plus(stderr, "*** GnuTLS Handshake failed ***\n");
437
fprintf(stderr, "\n*** Handshake failed ***\n");
851
/* Read OpenPGP packet that contains the wanted password */
444
//Retrieve OpenPGP packet that contains the wanted password
854
fprintf_plus(stderr, "Retrieving OpenPGP encrypted password from"
447
fprintf(stderr, "Retrieving pgp encrypted password from %s\n",
865
buffer_capacity = incbuffer(&buffer, buffer_length,
867
if(buffer_capacity == 0){
869
perror_plus("incbuffer");
879
sret = gnutls_record_recv(session, buffer+buffer_length,
452
if (buffer_length + BUFFER_SIZE > buffer_capacity){
453
buffer = realloc(buffer, buffer_capacity + BUFFER_SIZE);
458
buffer_capacity += BUFFER_SIZE;
461
ret = gnutls_record_recv
462
(es.session, buffer+buffer_length, BUFFER_SIZE);
886
468
case GNUTLS_E_INTERRUPTED:
887
469
case GNUTLS_E_AGAIN:
889
471
case GNUTLS_E_REHANDSHAKE:
891
ret = gnutls_handshake(session);
897
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
899
fprintf_plus(stderr, "*** GnuTLS Re-handshake failed "
472
ret = gnutls_handshake (es.session);
474
fprintf(stderr, "\n*** Handshake failed ***\n");
907
fprintf_plus(stderr, "Unknown error while reading data from"
908
" encrypted session with Mandos server\n");
909
gnutls_bye(session, GNUTLS_SHUT_RDWR);
481
fprintf(stderr, "Unknown error while reading data from"
482
" encrypted session with mandos server\n");
484
gnutls_bye (es.session, GNUTLS_SHUT_RDWR);
914
buffer_length += (size_t) sret;
919
fprintf_plus(stderr, "Closing TLS session\n");
928
ret = gnutls_bye(session, GNUTLS_SHUT_RDWR);
933
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
935
if(buffer_length > 0){
936
ssize_t decrypted_buffer_size;
937
decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,
939
if(decrypted_buffer_size >= 0){
488
buffer_length += (size_t) ret;
492
if (buffer_length > 0){
493
decrypted_buffer_size = pgp_packet_decrypt(buffer,
497
if (decrypted_buffer_size >= 0){
942
498
while(written < (size_t) decrypted_buffer_size){
948
ret = (int)fwrite(decrypted_buffer + written, 1,
949
(size_t)decrypted_buffer_size - written,
499
ret = (int)fwrite (decrypted_buffer + written, 1,
500
(size_t)decrypted_buffer_size - written,
951
502
if(ret == 0 and ferror(stdout)){
954
fprintf_plus(stderr, "Error writing encrypted data: %s\n",
504
fprintf(stderr, "Error writing encrypted data: %s\n",
960
510
written += (size_t)ret;
966
/* Shutdown procedure */
971
free(decrypted_buffer);
974
ret = (int)TEMP_FAILURE_RETRY(close(tcp_sd));
980
perror_plus("close");
982
gnutls_deinit(session);
512
free(decrypted_buffer);
521
fprintf(stderr, "Closing TLS session\n");
525
gnutls_bye (es.session, GNUTLS_SHUT_RDWR);
528
gnutls_deinit (es.session);
529
gnutls_certificate_free_credentials (es.cred);
530
gnutls_global_deinit ();
992
static void resolve_callback(AvahiSServiceResolver *r,
993
AvahiIfIndex interface,
995
AvahiResolverEvent event,
999
const char *host_name,
1000
const AvahiAddress *address,
1002
AVAHI_GCC_UNUSED AvahiStringList *txt,
1003
AVAHI_GCC_UNUSED AvahiLookupResultFlags
1005
AVAHI_GCC_UNUSED void* userdata){
534
static AvahiSimplePoll *simple_poll = NULL;
535
static AvahiServer *server = NULL;
537
static void resolve_callback(
538
AvahiSServiceResolver *r,
539
AvahiIfIndex interface,
540
AVAHI_GCC_UNUSED AvahiProtocol protocol,
541
AvahiResolverEvent event,
545
const char *host_name,
546
const AvahiAddress *address,
548
AVAHI_GCC_UNUSED AvahiStringList *txt,
549
AVAHI_GCC_UNUSED AvahiLookupResultFlags flags,
550
AVAHI_GCC_UNUSED void* userdata) {
552
assert(r); /* Spurious warning */
1010
554
/* Called whenever a service has been resolved successfully or
1019
559
case AVAHI_RESOLVER_FAILURE:
1020
fprintf_plus(stderr, "(Avahi Resolver) Failed to resolve service "
1021
"'%s' of type '%s' in domain '%s': %s\n", name, type,
1023
avahi_strerror(avahi_server_errno(mc.server)));
560
fprintf(stderr, "(Resolver) Failed to resolve service '%s' of"
561
" type '%s' in domain '%s': %s\n", name, type, domain,
562
avahi_strerror(avahi_server_errno(server)));
1026
565
case AVAHI_RESOLVER_FOUND:
1028
567
char ip[AVAHI_ADDRESS_STR_MAX];
1029
568
avahi_address_snprint(ip, sizeof(ip), address);
1031
fprintf_plus(stderr, "Mandos server \"%s\" found on %s (%s, %"
1032
PRIdMAX ") on port %" PRIu16 "\n", name,
1033
host_name, ip, (intmax_t)interface, port);
570
fprintf(stderr, "Mandos server \"%s\" found on %s (%s) on"
571
" port %d\n", name, host_name, ip, port);
1035
int ret = start_mandos_communication(ip, (in_port_t)port,
1037
avahi_proto_to_af(proto));
1039
avahi_simple_poll_quit(simple_poll);
1041
if(not add_server(ip, (in_port_t)port, interface,
1042
avahi_proto_to_af(proto))){
1043
fprintf_plus(stderr, "Failed to add server \"%s\" to server"
573
int ret = start_mandos_communication(ip, port, interface);
1049
579
avahi_s_service_resolver_free(r);
1052
static void browse_callback(AvahiSServiceBrowser *b,
1053
AvahiIfIndex interface,
1054
AvahiProtocol protocol,
1055
AvahiBrowserEvent event,
1059
AVAHI_GCC_UNUSED AvahiLookupResultFlags
1061
AVAHI_GCC_UNUSED void* userdata){
1066
/* Called whenever a new services becomes available on the LAN or
1067
is removed from the LAN */
1075
case AVAHI_BROWSER_FAILURE:
1077
fprintf_plus(stderr, "(Avahi browser) %s\n",
1078
avahi_strerror(avahi_server_errno(mc.server)));
1079
avahi_simple_poll_quit(simple_poll);
1082
case AVAHI_BROWSER_NEW:
1083
/* We ignore the returned Avahi resolver object. In the callback
1084
function we free it. If the Avahi server is terminated before
1085
the callback function is called the Avahi server will free the
1088
if(avahi_s_service_resolver_new(mc.server, interface, protocol,
1089
name, type, domain, protocol, 0,
1090
resolve_callback, NULL) == NULL)
1091
fprintf_plus(stderr, "Avahi: Failed to resolve service '%s':"
1093
avahi_strerror(avahi_server_errno(mc.server)));
1096
case AVAHI_BROWSER_REMOVE:
1099
case AVAHI_BROWSER_ALL_FOR_NOW:
1100
case AVAHI_BROWSER_CACHE_EXHAUSTED:
1102
fprintf_plus(stderr, "No Mandos server found, still"
1109
/* Signal handler that stops main loop after SIGTERM */
1110
static void handle_sigterm(int sig){
1115
signal_received = sig;
1116
int old_errno = errno;
1117
/* set main loop to exit */
1118
if(simple_poll != NULL){
1119
avahi_simple_poll_quit(simple_poll);
1124
bool get_flags(const char *ifname, struct ifreq *ifr){
1128
int s = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1131
perror_plus("socket");
1135
strcpy(ifr->ifr_name, ifname);
1136
ret = ioctl(s, SIOCGIFFLAGS, ifr);
1140
perror_plus("ioctl SIOCGIFFLAGS");
1148
bool good_flags(const char *ifname, const struct ifreq *ifr){
1150
/* Reject the loopback device */
1151
if(ifr->ifr_flags & IFF_LOOPBACK){
1153
fprintf_plus(stderr, "Rejecting loopback interface \"%s\"\n",
1158
/* Accept point-to-point devices only if connect_to is specified */
1159
if(connect_to != NULL and (ifr->ifr_flags & IFF_POINTOPOINT)){
1161
fprintf_plus(stderr, "Accepting point-to-point interface"
1162
" \"%s\"\n", ifname);
1166
/* Otherwise, reject non-broadcast-capable devices */
1167
if(not (ifr->ifr_flags & IFF_BROADCAST)){
1169
fprintf_plus(stderr, "Rejecting non-broadcast interface"
1170
" \"%s\"\n", ifname);
1174
/* Reject non-ARP interfaces (including dummy interfaces) */
1175
if(ifr->ifr_flags & IFF_NOARP){
1177
fprintf_plus(stderr, "Rejecting non-ARP interface \"%s\"\n",
1183
/* Accept this device */
1185
fprintf_plus(stderr, "Interface \"%s\" is good\n", ifname);
1191
* This function determines if a directory entry in /sys/class/net
1192
* corresponds to an acceptable network device.
1193
* (This function is passed to scandir(3) as a filter function.)
1195
int good_interface(const struct dirent *if_entry){
1196
if(if_entry->d_name[0] == '.'){
1201
if(not get_flags(if_entry->d_name, &ifr)){
1203
fprintf_plus(stderr, "Failed to get flags for interface "
1204
"\"%s\"\n", if_entry->d_name);
1209
if(not good_flags(if_entry->d_name, &ifr)){
1216
* This function determines if a network interface is up.
1218
bool interface_is_up(const char *interface){
1220
if(not get_flags(interface, &ifr)){
1222
fprintf_plus(stderr, "Failed to get flags for interface "
1223
"\"%s\"\n", interface);
1228
return (bool)(ifr.ifr_flags & IFF_UP);
1232
* This function determines if a network interface is running
1234
bool interface_is_running(const char *interface){
1236
if(not get_flags(interface, &ifr)){
1238
fprintf_plus(stderr, "Failed to get flags for interface "
1239
"\"%s\"\n", interface);
1244
return (bool)(ifr.ifr_flags & IFF_RUNNING);
1247
int notdotentries(const struct dirent *direntry){
1248
/* Skip "." and ".." */
1249
if(direntry->d_name[0] == '.'
1250
and (direntry->d_name[1] == '\0'
1251
or (direntry->d_name[1] == '.'
1252
and direntry->d_name[2] == '\0'))){
1258
/* Is this directory entry a runnable program? */
1259
int runnable_hook(const struct dirent *direntry){
1264
if((direntry->d_name)[0] == '\0'){
1269
sret = strspn(direntry->d_name, "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
1270
"abcdefghijklmnopqrstuvwxyz"
1273
if((direntry->d_name)[sret] != '\0'){
1274
/* Contains non-allowed characters */
1276
fprintf_plus(stderr, "Ignoring hook \"%s\" with bad name\n",
1282
char *fullname = NULL;
1283
ret = asprintf(&fullname, "%s/%s", hookdir, direntry->d_name);
1285
perror_plus("asprintf");
1289
ret = stat(fullname, &st);
1292
perror_plus("Could not stat hook");
1296
if(not (S_ISREG(st.st_mode))){
1297
/* Not a regular file */
1299
fprintf_plus(stderr, "Ignoring hook \"%s\" - not a file\n",
1304
if(not (st.st_mode & (S_IXUSR | S_IXGRP | S_IXOTH))){
1305
/* Not executable */
1307
fprintf_plus(stderr, "Ignoring hook \"%s\" - not executable\n",
1313
fprintf_plus(stderr, "Hook \"%s\" is acceptable\n",
1319
int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval){
1321
struct timespec now;
1322
struct timespec waited_time;
1323
intmax_t block_time;
1326
if(mc.current_server == NULL){
1328
fprintf_plus(stderr, "Wait until first server is found."
1331
ret = avahi_simple_poll_iterate(s, -1);
1334
fprintf_plus(stderr, "Check current_server if we should run"
1337
/* the current time */
1338
ret = clock_gettime(CLOCK_MONOTONIC, &now);
1340
perror_plus("clock_gettime");
1343
/* Calculating in ms how long time between now and server
1344
who we visted longest time ago. Now - last seen. */
1345
waited_time.tv_sec = (now.tv_sec
1346
- mc.current_server->last_seen.tv_sec);
1347
waited_time.tv_nsec = (now.tv_nsec
1348
- mc.current_server->last_seen.tv_nsec);
1349
/* total time is 10s/10,000ms.
1350
Converting to s from ms by dividing by 1,000,
1351
and ns to ms by dividing by 1,000,000. */
1352
block_time = ((retry_interval
1353
- ((intmax_t)waited_time.tv_sec * 1000))
1354
- ((intmax_t)waited_time.tv_nsec / 1000000));
1357
fprintf_plus(stderr, "Blocking for %" PRIdMAX " ms\n",
1361
if(block_time <= 0){
1362
ret = start_mandos_communication(mc.current_server->ip,
1363
mc.current_server->port,
1364
mc.current_server->if_index,
1365
mc.current_server->af);
1367
avahi_simple_poll_quit(simple_poll);
1370
ret = clock_gettime(CLOCK_MONOTONIC,
1371
&mc.current_server->last_seen);
1373
perror_plus("clock_gettime");
1376
mc.current_server = mc.current_server->next;
1377
block_time = 0; /* Call avahi to find new Mandos
1378
servers, but don't block */
1381
ret = avahi_simple_poll_iterate(s, (int)block_time);
1384
if (ret > 0 or errno != EINTR){
1385
return (ret != 1) ? ret : 0;
1391
/* Set effective uid to 0, return errno */
1392
error_t raise_privileges(void){
1393
error_t old_errno = errno;
1394
error_t ret_errno = 0;
1395
if(seteuid(0) == -1){
1397
perror_plus("seteuid");
1403
/* Set effective and real user ID to 0. Return errno. */
1404
error_t raise_privileges_permanently(void){
1405
error_t old_errno = errno;
1406
error_t ret_errno = raise_privileges();
1411
if(setuid(0) == -1){
1413
perror_plus("seteuid");
1419
/* Set effective user ID to unprivileged saved user ID */
1420
error_t lower_privileges(void){
1421
error_t old_errno = errno;
1422
error_t ret_errno = 0;
1423
if(seteuid(uid) == -1){
1425
perror_plus("seteuid");
1431
/* Lower privileges permanently */
1432
error_t lower_privileges_permanently(void){
1433
error_t old_errno = errno;
1434
error_t ret_errno = 0;
1435
if(setuid(uid) == -1){
1437
perror_plus("setuid");
1443
bool run_network_hooks(const char *mode, const char *interface,
1445
struct dirent **direntries;
1446
struct dirent *direntry;
1448
int numhooks = scandir(hookdir, &direntries, runnable_hook,
1451
if(errno == ENOENT){
1453
fprintf_plus(stderr, "Network hook directory \"%s\" not"
1454
" found\n", hookdir);
1457
perror_plus("scandir");
1460
int devnull = open("/dev/null", O_RDONLY);
1461
for(int i = 0; i < numhooks; i++){
1462
direntry = direntries[i];
1463
char *fullname = NULL;
1464
ret = asprintf(&fullname, "%s/%s", hookdir, direntry->d_name);
1466
perror_plus("asprintf");
1470
fprintf_plus(stderr, "Running network hook \"%s\"\n",
1473
pid_t hook_pid = fork();
1476
/* Raise privileges */
1477
raise_privileges_permanently();
1482
perror_plus("setgid");
1484
/* Reset supplementary groups */
1486
ret = setgroups(0, NULL);
1488
perror_plus("setgroups");
1490
dup2(devnull, STDIN_FILENO);
1492
dup2(STDERR_FILENO, STDOUT_FILENO);
1493
ret = setenv("MANDOSNETHOOKDIR", hookdir, 1);
1495
perror_plus("setenv");
1498
ret = setenv("DEVICE", interface, 1);
1500
perror_plus("setenv");
1503
ret = setenv("VERBOSITY", debug ? "1" : "0", 1);
1505
perror_plus("setenv");
1508
ret = setenv("MODE", mode, 1);
1510
perror_plus("setenv");
1514
ret = asprintf(&delaystring, "%f", delay);
1516
perror_plus("asprintf");
1519
ret = setenv("DELAY", delaystring, 1);
1522
perror_plus("setenv");
1526
if(connect_to != NULL){
1527
ret = setenv("CONNECT", connect_to, 1);
1529
perror_plus("setenv");
1533
if(execl(fullname, direntry->d_name, mode, NULL) == -1){
1534
perror_plus("execl");
1535
_exit(EXIT_FAILURE);
1539
if(TEMP_FAILURE_RETRY(waitpid(hook_pid, &status, 0)) == -1){
1540
perror_plus("waitpid");
1544
if(WIFEXITED(status)){
1545
if(WEXITSTATUS(status) != 0){
1546
fprintf_plus(stderr, "Warning: network hook \"%s\" exited"
1547
" with status %d\n", direntry->d_name,
1548
WEXITSTATUS(status));
1552
} else if(WIFSIGNALED(status)){
1553
fprintf_plus(stderr, "Warning: network hook \"%s\" died by"
1554
" signal %d\n", direntry->d_name,
1559
fprintf_plus(stderr, "Warning: network hook \"%s\""
1560
" crashed\n", direntry->d_name);
1567
fprintf_plus(stderr, "Network hook \"%s\" ran successfully\n",
1576
error_t bring_up_interface(const char *const interface,
1579
error_t old_errno = errno;
1580
error_t ret_errno = 0;
1581
int ret, ret_setflags;
1582
struct ifreq network;
1583
unsigned int if_index = if_nametoindex(interface);
1585
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
1595
if(not interface_is_up(interface)){
1596
if(not get_flags(interface, &network) and debug){
1598
fprintf_plus(stderr, "Failed to get flags for interface "
1599
"\"%s\"\n", interface);
1602
network.ifr_flags |= IFF_UP;
1604
sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1607
perror_plus("socket");
1619
fprintf_plus(stderr, "Bringing up interface \"%s\"\n",
1623
/* Raise priviliges */
1627
/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO
1628
messages about the network interface to mess up the prompt */
1629
int ret_linux = klogctl(8, NULL, 5);
1630
bool restore_loglevel = true;
1631
if(ret_linux == -1){
1632
restore_loglevel = false;
1633
perror_plus("klogctl");
1635
#endif /* __linux__ */
1636
ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
1639
if(restore_loglevel){
1640
ret_linux = klogctl(7, NULL, 0);
1641
if(ret_linux == -1){
1642
perror_plus("klogctl");
1645
#endif /* __linux__ */
1647
/* Lower privileges */
1650
/* Close the socket */
1651
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1653
perror_plus("close");
1656
if(ret_setflags == -1){
1658
perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");
1663
fprintf_plus(stderr, "Interface \"%s\" is already up; good\n",
1667
/* Sleep checking until interface is running.
1668
Check every 0.25s, up to total time of delay */
1669
for(int i=0; i < delay * 4; i++){
1670
if(interface_is_running(interface)){
1673
struct timespec sleeptime = { .tv_nsec = 250000000 };
1674
ret = nanosleep(&sleeptime, NULL);
1675
if(ret == -1 and errno != EINTR){
1676
perror_plus("nanosleep");
1684
error_t take_down_interface(const char *const interface){
1686
error_t old_errno = errno;
1687
error_t ret_errno = 0;
1688
int ret, ret_setflags;
1689
struct ifreq network;
1690
unsigned int if_index = if_nametoindex(interface);
1692
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
1696
if(interface_is_up(interface)){
1697
if(not get_flags(interface, &network) and debug){
1699
fprintf_plus(stderr, "Failed to get flags for interface "
1700
"\"%s\"\n", interface);
1703
network.ifr_flags &= ~(short)IFF_UP; /* clear flag */
1705
sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1708
perror_plus("socket");
1714
fprintf_plus(stderr, "Taking down interface \"%s\"\n",
1718
/* Raise priviliges */
1721
ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
1724
/* Lower privileges */
1727
/* Close the socket */
1728
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1730
perror_plus("close");
1733
if(ret_setflags == -1){
1735
perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");
1740
fprintf_plus(stderr, "Interface \"%s\" is already down; odd\n",
1748
int main(int argc, char *argv[]){
1749
AvahiSServiceBrowser *sb = NULL;
1754
int exitcode = EXIT_SUCCESS;
1755
char *interfaces = NULL;
1756
size_t interfaces_size = 0;
1757
char *interfaces_to_take_down = NULL;
1758
size_t interfaces_to_take_down_size = 0;
1759
char tempdir[] = "/tmp/mandosXXXXXX";
1760
bool tempdir_created = false;
1761
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
1762
const char *seckey = PATHDIR "/" SECKEY;
1763
const char *pubkey = PATHDIR "/" PUBKEY;
1764
char *interfaces_hooks = NULL;
1765
size_t interfaces_hooks_size = 0;
1767
bool gnutls_initialized = false;
1768
bool gpgme_initialized = false;
1770
double retry_interval = 10; /* 10s between trying a server and
1771
retrying the same server again */
1773
struct sigaction old_sigterm_action = { .sa_handler = SIG_DFL };
1774
struct sigaction sigterm_action = { .sa_handler = handle_sigterm };
1779
/* Lower any group privileges we might have, just to be safe */
1783
perror_plus("setgid");
1786
/* Lower user privileges (temporarily) */
1790
perror_plus("seteuid");
1798
struct argp_option options[] = {
1799
{ .name = "debug", .key = 128,
1800
.doc = "Debug mode", .group = 3 },
1801
{ .name = "connect", .key = 'c',
1802
.arg = "ADDRESS:PORT",
1803
.doc = "Connect directly to a specific Mandos server",
1805
{ .name = "interface", .key = 'i',
1807
.doc = "Network interface that will be used to search for"
1810
{ .name = "seckey", .key = 's',
1812
.doc = "OpenPGP secret key file base name",
1814
{ .name = "pubkey", .key = 'p',
1816
.doc = "OpenPGP public key file base name",
1818
{ .name = "dh-bits", .key = 129,
1820
.doc = "Bit length of the prime number used in the"
1821
" Diffie-Hellman key exchange",
1823
{ .name = "priority", .key = 130,
1825
.doc = "GnuTLS priority string for the TLS handshake",
1827
{ .name = "delay", .key = 131,
1829
.doc = "Maximum delay to wait for interface startup",
1831
{ .name = "retry", .key = 132,
1833
.doc = "Retry interval used when denied by the Mandos server",
1835
{ .name = "network-hook-dir", .key = 133,
1837
.doc = "Directory where network hooks are located",
1840
* These reproduce what we would get without ARGP_NO_HELP
1842
{ .name = "help", .key = '?',
1843
.doc = "Give this help list", .group = -1 },
1844
{ .name = "usage", .key = -3,
1845
.doc = "Give a short usage message", .group = -1 },
1846
{ .name = "version", .key = 'V',
1847
.doc = "Print program version", .group = -1 },
1851
error_t parse_opt(int key, char *arg,
1852
struct argp_state *state){
1855
case 128: /* --debug */
1858
case 'c': /* --connect */
1861
case 'i': /* --interface */
1862
ret_errno = argz_add_sep(&interfaces, &interfaces_size, arg,
1865
argp_error(state, "%s", strerror(ret_errno));
1868
case 's': /* --seckey */
1871
case 'p': /* --pubkey */
1874
case 129: /* --dh-bits */
1876
tmpmax = strtoimax(arg, &tmp, 10);
1877
if(errno != 0 or tmp == arg or *tmp != '\0'
1878
or tmpmax != (typeof(mc.dh_bits))tmpmax){
1879
argp_error(state, "Bad number of DH bits");
1881
mc.dh_bits = (typeof(mc.dh_bits))tmpmax;
1883
case 130: /* --priority */
1886
case 131: /* --delay */
1888
delay = strtof(arg, &tmp);
1889
if(errno != 0 or tmp == arg or *tmp != '\0'){
1890
argp_error(state, "Bad delay");
1892
case 132: /* --retry */
1894
retry_interval = strtod(arg, &tmp);
1895
if(errno != 0 or tmp == arg or *tmp != '\0'
1896
or (retry_interval * 1000) > INT_MAX
1897
or retry_interval < 0){
1898
argp_error(state, "Bad retry interval");
1901
case 133: /* --network-hook-dir */
1905
* These reproduce what we would get without ARGP_NO_HELP
1907
case '?': /* --help */
1908
argp_state_help(state, state->out_stream,
1909
(ARGP_HELP_STD_HELP | ARGP_HELP_EXIT_ERR)
1910
& ~(unsigned int)ARGP_HELP_EXIT_OK);
1911
case -3: /* --usage */
1912
argp_state_help(state, state->out_stream,
1913
ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);
1914
case 'V': /* --version */
1915
fprintf_plus(state->out_stream, "%s\n", argp_program_version);
1916
exit(argp_err_exit_status);
1919
return ARGP_ERR_UNKNOWN;
1924
struct argp argp = { .options = options, .parser = parse_opt,
1926
.doc = "Mandos client -- Get and decrypt"
1927
" passwords from a Mandos server" };
1928
ret = argp_parse(&argp, argc, argv,
1929
ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);
582
static void browse_callback(
583
AvahiSServiceBrowser *b,
584
AvahiIfIndex interface,
585
AvahiProtocol protocol,
586
AvahiBrowserEvent event,
590
AVAHI_GCC_UNUSED AvahiLookupResultFlags flags,
593
AvahiServer *s = userdata;
594
assert(b); /* Spurious warning */
596
/* Called whenever a new services becomes available on the LAN or
597
is removed from the LAN */
1936
perror_plus("argp_parse");
1937
exitcode = EX_OSERR;
1940
exitcode = EX_USAGE;
1946
/* Work around Debian bug #633582:
1947
<http://bugs.debian.org/633582> */
1949
/* Re-raise priviliges */
1950
if(raise_privileges() == 0){
1953
if(strcmp(seckey, PATHDIR "/" SECKEY) == 0){
1954
int seckey_fd = open(seckey, O_RDONLY);
1955
if(seckey_fd == -1){
1956
perror_plus("open");
1958
ret = (int)TEMP_FAILURE_RETRY(fstat(seckey_fd, &st));
1960
perror_plus("fstat");
1962
if(S_ISREG(st.st_mode)
1963
and st.st_uid == 0 and st.st_gid == 0){
1964
ret = fchown(seckey_fd, uid, gid);
1966
perror_plus("fchown");
1970
TEMP_FAILURE_RETRY(close(seckey_fd));
1974
if(strcmp(pubkey, PATHDIR "/" PUBKEY) == 0){
1975
int pubkey_fd = open(pubkey, O_RDONLY);
1976
if(pubkey_fd == -1){
1977
perror_plus("open");
1979
ret = (int)TEMP_FAILURE_RETRY(fstat(pubkey_fd, &st));
1981
perror_plus("fstat");
1983
if(S_ISREG(st.st_mode)
1984
and st.st_uid == 0 and st.st_gid == 0){
1985
ret = fchown(pubkey_fd, uid, gid);
1987
perror_plus("fchown");
1991
TEMP_FAILURE_RETRY(close(pubkey_fd));
1995
/* Lower privileges */
1999
perror_plus("seteuid");
2004
/* Remove empty interface names */
2006
char *interface = NULL;
2007
while((interface = argz_next(interfaces, interfaces_size,
2009
if(if_nametoindex(interface) == 0){
2010
if(interface[0] != '\0' and strcmp(interface, "none") != 0){
2011
fprintf_plus(stderr, "Not using nonexisting interface"
2012
" \"%s\"\n", interface);
2014
argz_delete(&interfaces, &interfaces_size, interface);
2020
/* Run network hooks */
2023
if(interfaces != NULL){
2024
interfaces_hooks = malloc(interfaces_size);
2025
if(interfaces_hooks == NULL){
2026
perror_plus("malloc");
2029
memcpy(interfaces_hooks, interfaces, interfaces_size);
2030
interfaces_hooks_size = interfaces_size;
2031
argz_stringify(interfaces_hooks, interfaces_hooks_size,
2034
if(not run_network_hooks("start", interfaces_hooks != NULL ?
2035
interfaces_hooks : "", delay)){
2041
avahi_set_log_function(empty_log);
2044
/* Initialize Avahi early so avahi_simple_poll_quit() can be called
2045
from the signal handler */
2046
/* Initialize the pseudo-RNG for Avahi */
2047
srand((unsigned int) time(NULL));
2048
simple_poll = avahi_simple_poll_new();
2049
if(simple_poll == NULL){
2050
fprintf_plus(stderr,
2051
"Avahi: Failed to create simple poll object.\n");
2052
exitcode = EX_UNAVAILABLE;
2056
sigemptyset(&sigterm_action.sa_mask);
2057
ret = sigaddset(&sigterm_action.sa_mask, SIGINT);
2059
perror_plus("sigaddset");
2060
exitcode = EX_OSERR;
2063
ret = sigaddset(&sigterm_action.sa_mask, SIGHUP);
2065
perror_plus("sigaddset");
2066
exitcode = EX_OSERR;
2069
ret = sigaddset(&sigterm_action.sa_mask, SIGTERM);
2071
perror_plus("sigaddset");
2072
exitcode = EX_OSERR;
2075
/* Need to check if the handler is SIG_IGN before handling:
2076
| [[info:libc:Initial Signal Actions]] |
2077
| [[info:libc:Basic Signal Handling]] |
2079
ret = sigaction(SIGINT, NULL, &old_sigterm_action);
2081
perror_plus("sigaction");
2084
if(old_sigterm_action.sa_handler != SIG_IGN){
2085
ret = sigaction(SIGINT, &sigterm_action, NULL);
2087
perror_plus("sigaction");
2088
exitcode = EX_OSERR;
2092
ret = sigaction(SIGHUP, NULL, &old_sigterm_action);
2094
perror_plus("sigaction");
2097
if(old_sigterm_action.sa_handler != SIG_IGN){
2098
ret = sigaction(SIGHUP, &sigterm_action, NULL);
2100
perror_plus("sigaction");
2101
exitcode = EX_OSERR;
2105
ret = sigaction(SIGTERM, NULL, &old_sigterm_action);
2107
perror_plus("sigaction");
2110
if(old_sigterm_action.sa_handler != SIG_IGN){
2111
ret = sigaction(SIGTERM, &sigterm_action, NULL);
2113
perror_plus("sigaction");
2114
exitcode = EX_OSERR;
2119
/* If no interfaces were specified, make a list */
2120
if(interfaces == NULL){
2121
struct dirent **direntries;
2122
/* Look for any good interfaces */
2123
ret = scandir(sys_class_net, &direntries, good_interface,
2126
/* Add all found interfaces to interfaces list */
2127
for(int i = 0; i < ret; ++i){
2128
ret_errno = argz_add(&interfaces, &interfaces_size,
2129
direntries[i]->d_name);
2131
perror_plus("argz_add");
2135
fprintf_plus(stderr, "Will use interface \"%s\"\n",
2136
direntries[i]->d_name);
2142
fprintf_plus(stderr, "Could not find a network interface\n");
2143
exitcode = EXIT_FAILURE;
2148
/* If we only got one interface, explicitly use only that one */
2149
if(argz_count(interfaces, interfaces_size) == 1){
2151
fprintf_plus(stderr, "Using only interface \"%s\"\n",
2154
if_index = (AvahiIfIndex)if_nametoindex(interfaces);
2157
/* Bring up interfaces which are down */
2158
if(not (argz_count(interfaces, interfaces_size) == 1
2159
and strcmp(interfaces, "none") == 0)){
2160
char *interface = NULL;
2161
while((interface = argz_next(interfaces, interfaces_size,
2163
bool interface_was_up = interface_is_up(interface);
2164
ret = bring_up_interface(interface, delay);
2165
if(not interface_was_up){
2168
perror_plus("Failed to bring up interface");
2170
ret_errno = argz_add(&interfaces_to_take_down,
2171
&interfaces_to_take_down_size,
2178
interfaces_size = 0;
2179
if(debug and (interfaces_to_take_down == NULL)){
2180
fprintf_plus(stderr, "No interfaces were brought up\n");
2188
ret = init_gnutls_global(pubkey, seckey);
2190
fprintf_plus(stderr, "init_gnutls_global failed\n");
2191
exitcode = EX_UNAVAILABLE;
2194
gnutls_initialized = true;
2201
if(mkdtemp(tempdir) == NULL){
2202
perror_plus("mkdtemp");
2205
tempdir_created = true;
2211
if(not init_gpgme(pubkey, seckey, tempdir)){
2212
fprintf_plus(stderr, "init_gpgme failed\n");
2213
exitcode = EX_UNAVAILABLE;
2216
gpgme_initialized = true;
2223
if(connect_to != NULL){
2224
/* Connect directly, do not use Zeroconf */
2225
/* (Mainly meant for debugging) */
2226
char *address = strrchr(connect_to, ':');
2228
if(address == NULL){
2229
fprintf_plus(stderr, "No colon in address\n");
2230
exitcode = EX_USAGE;
2240
tmpmax = strtoimax(address+1, &tmp, 10);
2241
if(errno != 0 or tmp == address+1 or *tmp != '\0'
2242
or tmpmax != (in_port_t)tmpmax){
2243
fprintf_plus(stderr, "Bad port number\n");
2244
exitcode = EX_USAGE;
2252
port = (in_port_t)tmpmax;
2254
/* Colon in address indicates IPv6 */
2256
if(strchr(connect_to, ':') != NULL){
2258
/* Accept [] around IPv6 address - see RFC 5952 */
2259
if(connect_to[0] == '[' and address[-1] == ']')
2267
address = connect_to;
2273
while(not quit_now){
2274
ret = start_mandos_communication(address, port, if_index, af);
2275
if(quit_now or ret == 0){
2279
fprintf_plus(stderr, "Retrying in %d seconds\n",
2280
(int)retry_interval);
2282
sleep((int)retry_interval);
2286
exitcode = EXIT_SUCCESS;
601
case AVAHI_BROWSER_FAILURE:
603
fprintf(stderr, "(Browser) %s\n",
604
avahi_strerror(avahi_server_errno(server)));
605
avahi_simple_poll_quit(simple_poll);
608
case AVAHI_BROWSER_NEW:
609
/* We ignore the returned resolver object. In the callback
610
function we free it. If the server is terminated before
611
the callback function is called the server will free
612
the resolver for us. */
614
if (!(avahi_s_service_resolver_new(s, interface, protocol, name,
616
AVAHI_PROTO_INET6, 0,
617
resolve_callback, s)))
618
fprintf(stderr, "Failed to resolve service '%s': %s\n", name,
619
avahi_strerror(avahi_server_errno(s)));
622
case AVAHI_BROWSER_REMOVE:
625
case AVAHI_BROWSER_ALL_FOR_NOW:
626
case AVAHI_BROWSER_CACHE_EXHAUSTED:
631
/* Combines file name and path and returns the malloced new
632
string. some sane checks could/should be added */
633
static const char *combinepath(const char *first, const char *second){
634
size_t f_len = strlen(first);
635
size_t s_len = strlen(second);
636
char *tmp = malloc(f_len + s_len + 2);
641
memcpy(tmp, first, f_len);
645
memcpy(tmp + f_len + 1, second, s_len);
647
tmp[f_len + 1 + s_len] = '\0';
652
int main(AVAHI_GCC_UNUSED int argc, AVAHI_GCC_UNUSED char*argv[]) {
2297
653
AvahiServerConfig config;
2298
/* Do not publish any local Zeroconf records */
654
AvahiSServiceBrowser *sb = NULL;
657
int returncode = EXIT_SUCCESS;
658
const char *interface = NULL;
659
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
660
char *connect_to = NULL;
663
static struct option long_options[] = {
664
{"debug", no_argument, (int *)&debug, 1},
665
{"connect", required_argument, 0, 'C'},
666
{"interface", required_argument, 0, 'i'},
667
{"certdir", required_argument, 0, 'd'},
668
{"certkey", required_argument, 0, 'c'},
669
{"certfile", required_argument, 0, 'k'},
672
int option_index = 0;
673
ret = getopt_long (argc, argv, "i:", long_options,
703
certfile = combinepath(certdir, certfile);
704
if (certfile == NULL){
705
perror("combinepath");
709
if(interface != NULL){
710
if_index = (AvahiIfIndex) if_nametoindex(interface);
712
fprintf(stderr, "No such interface: \"%s\"\n", interface);
717
if(connect_to != NULL){
718
/* Connect directly, do not use Zeroconf */
719
/* (Mainly meant for debugging) */
720
char *address = strrchr(connect_to, ':');
722
fprintf(stderr, "No colon in address\n");
726
uint16_t port = (uint16_t) strtol(address+1, NULL, 10);
728
perror("Bad port number");
732
address = connect_to;
733
ret = start_mandos_communication(address, port, if_index);
741
certkey = combinepath(certdir, certkey);
742
if (certkey == NULL){
743
perror("combinepath");
748
avahi_set_log_function(empty_log);
751
/* Initialize the psuedo-RNG */
752
srand((unsigned int) time(NULL));
754
/* Allocate main loop object */
755
if (!(simple_poll = avahi_simple_poll_new())) {
756
fprintf(stderr, "Failed to create simple poll object.\n");
761
/* Do not publish any local records */
2299
762
avahi_server_config_init(&config);
2300
763
config.publish_hinfo = 0;
2301
764
config.publish_addresses = 0;
2302
765
config.publish_workstation = 0;
2303
766
config.publish_domain = 0;
2305
768
/* Allocate a new server */
2306
mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),
2307
&config, NULL, NULL, &ret_errno);
2309
/* Free the Avahi configuration data */
769
server = avahi_server_new(avahi_simple_poll_get(simple_poll),
770
&config, NULL, NULL, &error);
772
/* Free the configuration data */
2310
773
avahi_server_config_free(&config);
2313
/* Check if creating the Avahi server object succeeded */
2314
if(mc.server == NULL){
2315
fprintf_plus(stderr, "Failed to create Avahi server: %s\n",
2316
avahi_strerror(ret_errno));
2317
exitcode = EX_UNAVAILABLE;
2325
/* Create the Avahi service browser */
2326
sb = avahi_s_service_browser_new(mc.server, if_index,
2327
AVAHI_PROTO_UNSPEC, "_mandos._tcp",
2328
NULL, 0, browse_callback, NULL);
2330
fprintf_plus(stderr, "Failed to create service browser: %s\n",
2331
avahi_strerror(avahi_server_errno(mc.server)));
2332
exitcode = EX_UNAVAILABLE;
2340
/* Run the main loop */
2343
fprintf_plus(stderr, "Starting Avahi loop search\n");
2346
ret = avahi_loop_with_timeout(simple_poll,
2347
(int)(retry_interval * 1000));
2349
fprintf_plus(stderr, "avahi_loop_with_timeout exited %s\n",
2350
(ret == 0) ? "successfully" : "with error");
2356
fprintf_plus(stderr, "%s exiting\n", argv[0]);
2359
/* Cleanup things */
2361
avahi_s_service_browser_free(sb);
2363
if(mc.server != NULL)
2364
avahi_server_free(mc.server);
2366
if(simple_poll != NULL)
2367
avahi_simple_poll_free(simple_poll);
2369
if(gnutls_initialized){
2370
gnutls_certificate_free_credentials(mc.cred);
2371
gnutls_global_deinit();
2372
gnutls_dh_params_deinit(mc.dh_params);
2375
if(gpgme_initialized){
2376
gpgme_release(mc.ctx);
2379
/* Cleans up the circular linked list of Mandos servers the client
2381
if(mc.current_server != NULL){
2382
mc.current_server->prev->next = NULL;
2383
while(mc.current_server != NULL){
2384
server *next = mc.current_server->next;
2385
free(mc.current_server);
2386
mc.current_server = next;
2390
/* Re-raise priviliges */
2394
/* Run network hooks */
2395
run_network_hooks("stop", interfaces_hooks != NULL ?
2396
interfaces_hooks : "", delay);
2398
/* Take down the network interfaces which were brought up */
2400
char *interface = NULL;
2401
while((interface=argz_next(interfaces_to_take_down,
2402
interfaces_to_take_down_size,
2404
ret_errno = take_down_interface(interface);
2407
perror_plus("Failed to take down interface");
2410
if(debug and (interfaces_to_take_down == NULL)){
2411
fprintf_plus(stderr, "No interfaces needed to be taken"
2416
lower_privileges_permanently();
2419
free(interfaces_to_take_down);
2420
free(interfaces_hooks);
2422
/* Removes the GPGME temp directory and all files inside */
2423
if(tempdir_created){
2424
struct dirent **direntries = NULL;
2425
struct dirent *direntry = NULL;
2426
int numentries = scandir(tempdir, &direntries, notdotentries,
2428
if (numentries > 0){
2429
for(int i = 0; i < numentries; i++){
2430
direntry = direntries[i];
2431
char *fullname = NULL;
2432
ret = asprintf(&fullname, "%s/%s", tempdir,
2435
perror_plus("asprintf");
2438
ret = remove(fullname);
2440
fprintf_plus(stderr, "remove(\"%s\"): %s\n", fullname,
2447
/* need to clean even if 0 because man page doesn't specify */
2449
if (numentries == -1){
2450
perror_plus("scandir");
2452
ret = rmdir(tempdir);
2453
if(ret == -1 and errno != ENOENT){
2454
perror_plus("rmdir");
2459
sigemptyset(&old_sigterm_action.sa_mask);
2460
old_sigterm_action.sa_handler = SIG_DFL;
2461
ret = (int)TEMP_FAILURE_RETRY(sigaction(signal_received,
2462
&old_sigterm_action,
2465
perror_plus("sigaction");
2468
ret = raise(signal_received);
2469
} while(ret != 0 and errno == EINTR);
2471
perror_plus("raise");
2474
TEMP_FAILURE_RETRY(pause());
775
/* Check if creating the server object succeeded */
777
fprintf(stderr, "Failed to create server: %s\n",
778
avahi_strerror(error));
779
returncode = EXIT_FAILURE;
783
/* Create the service browser */
784
sb = avahi_s_service_browser_new(server, if_index,
786
"_mandos._tcp", NULL, 0,
787
browse_callback, server);
789
fprintf(stderr, "Failed to create service browser: %s\n",
790
avahi_strerror(avahi_server_errno(server)));
791
returncode = EXIT_FAILURE;
795
/* Run the main loop */
798
fprintf(stderr, "Starting avahi loop search\n");
801
avahi_simple_poll_loop(simple_poll);
806
fprintf(stderr, "%s exiting\n", argv[0]);
811
avahi_s_service_browser_free(sb);
814
avahi_server_free(server);
817
avahi_simple_poll_free(simple_poll);