107
33
#include <avahi-common/malloc.h>
108
34
#include <avahi-common/error.h>
111
#include <gnutls/gnutls.h> /* All GnuTLS types, constants and
114
init_gnutls_session(),
116
#include <gnutls/openpgp.h>
117
/* gnutls_certificate_set_openpgp_key_file(),
118
GNUTLS_OPENPGP_FMT_BASE64 */
121
#include <gpgme.h> /* All GPGME types, constants and
124
GPGME_PROTOCOL_OpenPGP,
37
#include <sys/types.h> /* socket(), setsockopt(), inet_pton() */
38
#include <sys/socket.h> /* socket(), setsockopt(), struct sockaddr_in6, struct in6_addr, inet_pton() */
39
#include <gnutls/gnutls.h> /* ALL GNUTLS STUFF */
40
#include <gnutls/openpgp.h> /* gnutls with openpgp stuff */
42
#include <unistd.h> /* close() */
43
#include <netinet/in.h>
44
#include <stdbool.h> /* true */
45
#include <string.h> /* memset */
46
#include <arpa/inet.h> /* inet_pton() */
47
#include <iso646.h> /* not */
50
#include <errno.h> /* perror() */
55
#define CERT_ROOT "/conf/conf.d/cryptkeyreq/"
57
#define CERTFILE CERT_ROOT "openpgp-client.txt"
58
#define KEYFILE CERT_ROOT "openpgp-client-key.txt"
127
59
#define BUFFER_SIZE 256
129
#define PATHDIR "/conf/conf.d/mandos"
130
#define SECKEY "seckey.txt"
131
#define PUBKEY "pubkey.txt"
132
#define HOOKDIR "/lib/mandos/network-hooks.d"
134
62
bool debug = false;
135
static const char mandos_protocol_version[] = "1";
136
const char *argp_program_version = "mandos-client " VERSION;
137
const char *argp_program_bug_address = "<mandos@recompile.se>";
138
static const char sys_class_net[] = "/sys/class/net";
139
char *connect_to = NULL;
140
const char *hookdir = HOOKDIR;
144
/* Doubly linked list that need to be circularly linked when used */
145
typedef struct server{
148
AvahiIfIndex if_index;
150
struct timespec last_seen;
155
/* Used for passing in values through the Avahi callback functions */
65
gnutls_session_t session;
158
66
gnutls_certificate_credentials_t cred;
159
unsigned int dh_bits;
160
67
gnutls_dh_params_t dh_params;
161
const char *priority;
71
ssize_t gpg_packet_decrypt (char *packet, size_t packet_size, char **new_packet, char *homedir){
72
gpgme_data_t dh_crypto, dh_plain;
163
server *current_server;
166
/* global so signal handler can reach it*/
167
AvahiSimplePoll *simple_poll;
169
sig_atomic_t quit_now = 0;
170
int signal_received = 0;
172
/* Function to use when printing errors */
173
void perror_plus(const char *print_text){
175
fprintf(stderr, "Mandos plugin %s: ",
176
program_invocation_short_name);
181
__attribute__((format (gnu_printf, 2, 3)))
182
int fprintf_plus(FILE *stream, const char *format, ...){
184
va_start (ap, format);
186
TEMP_FAILURE_RETRY(fprintf(stream, "Mandos plugin %s: ",
187
program_invocation_short_name));
188
return TEMP_FAILURE_RETRY(vfprintf(stream, format, ap));
192
* Make additional room in "buffer" for at least BUFFER_SIZE more
193
* bytes. "buffer_capacity" is how much is currently allocated,
194
* "buffer_length" is how much is already used.
196
size_t incbuffer(char **buffer, size_t buffer_length,
197
size_t buffer_capacity){
198
if(buffer_length + BUFFER_SIZE > buffer_capacity){
199
*buffer = realloc(*buffer, buffer_capacity + BUFFER_SIZE);
203
buffer_capacity += BUFFER_SIZE;
205
return buffer_capacity;
208
/* Add server to set of servers to retry periodically */
209
bool add_server(const char *ip, in_port_t port, AvahiIfIndex if_index,
210
int af, server **current_server){
212
server *new_server = malloc(sizeof(server));
213
if(new_server == NULL){
214
perror_plus("malloc");
217
*new_server = (server){ .ip = strdup(ip),
219
.if_index = if_index,
221
if(new_server->ip == NULL){
222
perror_plus("strdup");
225
/* Special case of first server */
226
if(*current_server == NULL){
227
new_server->next = new_server;
228
new_server->prev = new_server;
229
*current_server = new_server;
230
/* Place the new server last in the list */
232
new_server->next = *current_server;
233
new_server->prev = (*current_server)->prev;
234
new_server->prev->next = new_server;
235
(*current_server)->prev = new_server;
237
ret = clock_gettime(CLOCK_MONOTONIC, &(*current_server)->last_seen);
239
perror_plus("clock_gettime");
248
static bool init_gpgme(const char *seckey, const char *pubkey,
249
const char *tempdir, mandos_context *mc){
76
size_t new_packet_capacity = 0;
77
size_t new_packet_length = 0;
251
78
gpgme_engine_info_t engine_info;
254
* Helper function to insert pub and seckey to the engine keyring.
256
bool import_key(const char *filename){
259
gpgme_data_t pgp_data;
261
fd = (int)TEMP_FAILURE_RETRY(open(filename, O_RDONLY));
267
rc = gpgme_data_new_from_fd(&pgp_data, fd);
268
if(rc != GPG_ERR_NO_ERROR){
269
fprintf_plus(stderr, "bad gpgme_data_new_from_fd: %s: %s\n",
270
gpgme_strsource(rc), gpgme_strerror(rc));
274
rc = gpgme_op_import(mc->ctx, pgp_data);
275
if(rc != GPG_ERR_NO_ERROR){
276
fprintf_plus(stderr, "bad gpgme_op_import: %s: %s\n",
277
gpgme_strsource(rc), gpgme_strerror(rc));
281
ret = (int)TEMP_FAILURE_RETRY(close(fd));
283
perror_plus("close");
285
gpgme_data_release(pgp_data);
290
fprintf_plus(stderr, "Initializing GPGME\n");
81
fprintf(stderr, "Attempting to decrypt password from gpg packet\n");
294
85
gpgme_check_version(NULL);
295
rc = gpgme_engine_check_version(GPGME_PROTOCOL_OpenPGP);
296
if(rc != GPG_ERR_NO_ERROR){
297
fprintf_plus(stderr, "bad gpgme_engine_check_version: %s: %s\n",
298
gpgme_strsource(rc), gpgme_strerror(rc));
86
gpgme_engine_check_version(GPGME_PROTOCOL_OpenPGP);
302
/* Set GPGME home directory for the OpenPGP engine only */
303
rc = gpgme_get_engine_info(&engine_info);
304
if(rc != GPG_ERR_NO_ERROR){
305
fprintf_plus(stderr, "bad gpgme_get_engine_info: %s: %s\n",
306
gpgme_strsource(rc), gpgme_strerror(rc));
88
/* Set GPGME home directory */
89
rc = gpgme_get_engine_info (&engine_info);
90
if (rc != GPG_ERR_NO_ERROR){
91
fprintf(stderr, "bad gpgme_get_engine_info: %s: %s\n",
92
gpgme_strsource(rc), gpgme_strerror(rc));
309
95
while(engine_info != NULL){
310
96
if(engine_info->protocol == GPGME_PROTOCOL_OpenPGP){
311
97
gpgme_set_engine_info(GPGME_PROTOCOL_OpenPGP,
312
engine_info->file_name, tempdir);
98
engine_info->file_name, homedir);
315
101
engine_info = engine_info->next;
317
103
if(engine_info == NULL){
318
fprintf_plus(stderr, "Could not set GPGME home dir to %s\n",
323
/* Create new GPGME "context" */
324
rc = gpgme_new(&(mc->ctx));
325
if(rc != GPG_ERR_NO_ERROR){
326
fprintf_plus(stderr, "Mandos plugin mandos-client: "
327
"bad gpgme_new: %s: %s\n", gpgme_strsource(rc),
332
if(not import_key(pubkey) or not import_key(seckey)){
340
* Decrypt OpenPGP data.
341
* Returns -1 on error
343
static ssize_t pgp_packet_decrypt(const char *cryptotext,
347
gpgme_data_t dh_crypto, dh_plain;
350
size_t plaintext_capacity = 0;
351
ssize_t plaintext_length = 0;
354
fprintf_plus(stderr, "Trying to decrypt OpenPGP data\n");
357
/* Create new GPGME data buffer from memory cryptotext */
358
rc = gpgme_data_new_from_mem(&dh_crypto, cryptotext, crypto_size,
360
if(rc != GPG_ERR_NO_ERROR){
361
fprintf_plus(stderr, "bad gpgme_data_new_from_mem: %s: %s\n",
362
gpgme_strsource(rc), gpgme_strerror(rc));
104
fprintf(stderr, "Could not set home dir to %s\n", homedir);
108
/* Create new GPGME data buffer from packet buffer */
109
rc = gpgme_data_new_from_mem(&dh_crypto, packet, packet_size, 0);
110
if (rc != GPG_ERR_NO_ERROR){
111
fprintf(stderr, "bad gpgme_data_new_from_mem: %s: %s\n",
112
gpgme_strsource(rc), gpgme_strerror(rc));
366
116
/* Create new empty GPGME data buffer for the plaintext */
367
117
rc = gpgme_data_new(&dh_plain);
368
if(rc != GPG_ERR_NO_ERROR){
369
fprintf_plus(stderr, "Mandos plugin mandos-client: "
370
"bad gpgme_data_new: %s: %s\n",
371
gpgme_strsource(rc), gpgme_strerror(rc));
372
gpgme_data_release(dh_crypto);
376
/* Decrypt data from the cryptotext data buffer to the plaintext
378
rc = gpgme_op_decrypt(mc->ctx, dh_crypto, dh_plain);
379
if(rc != GPG_ERR_NO_ERROR){
380
fprintf_plus(stderr, "bad gpgme_op_decrypt: %s: %s\n",
381
gpgme_strsource(rc), gpgme_strerror(rc));
382
plaintext_length = -1;
384
gpgme_decrypt_result_t result;
385
result = gpgme_op_decrypt_result(mc->ctx);
387
fprintf_plus(stderr, "gpgme_op_decrypt_result failed\n");
389
fprintf_plus(stderr, "Unsupported algorithm: %s\n",
390
result->unsupported_algorithm);
391
fprintf_plus(stderr, "Wrong key usage: %u\n",
392
result->wrong_key_usage);
393
if(result->file_name != NULL){
394
fprintf_plus(stderr, "File name: %s\n", result->file_name);
396
gpgme_recipient_t recipient;
397
recipient = result->recipients;
118
if (rc != GPG_ERR_NO_ERROR){
119
fprintf(stderr, "bad gpgme_data_new: %s: %s\n",
120
gpgme_strsource(rc), gpgme_strerror(rc));
124
/* Create new GPGME "context" */
125
rc = gpgme_new(&ctx);
126
if (rc != GPG_ERR_NO_ERROR){
127
fprintf(stderr, "bad gpgme_new: %s: %s\n",
128
gpgme_strsource(rc), gpgme_strerror(rc));
132
/* Decrypt data from the FILE pointer to the plaintext data buffer */
133
rc = gpgme_op_decrypt(ctx, dh_crypto, dh_plain);
134
if (rc != GPG_ERR_NO_ERROR){
135
fprintf(stderr, "bad gpgme_op_decrypt: %s: %s\n",
136
gpgme_strsource(rc), gpgme_strerror(rc));
141
fprintf(stderr, "decryption of gpg packet succeeded\n");
145
gpgme_decrypt_result_t result;
146
result = gpgme_op_decrypt_result(ctx);
148
fprintf(stderr, "gpgme_op_decrypt_result failed\n");
150
fprintf(stderr, "Unsupported algorithm: %s\n", result->unsupported_algorithm);
151
fprintf(stderr, "Wrong key usage: %d\n", result->wrong_key_usage);
152
if(result->file_name != NULL){
153
fprintf(stderr, "File name: %s\n", result->file_name);
155
gpgme_recipient_t recipient;
156
recipient = result->recipients;
398
158
while(recipient != NULL){
399
fprintf_plus(stderr, "Public key algorithm: %s\n",
400
gpgme_pubkey_algo_name
401
(recipient->pubkey_algo));
402
fprintf_plus(stderr, "Key ID: %s\n", recipient->keyid);
403
fprintf_plus(stderr, "Secret key available: %s\n",
404
recipient->status == GPG_ERR_NO_SECKEY
159
fprintf(stderr, "Public key algorithm: %s\n",
160
gpgme_pubkey_algo_name(recipient->pubkey_algo));
161
fprintf(stderr, "Key ID: %s\n", recipient->keyid);
162
fprintf(stderr, "Secret key available: %s\n",
163
recipient->status == GPG_ERR_NO_SECKEY ? "No" : "Yes");
406
164
recipient = recipient->next;
414
fprintf_plus(stderr, "Decryption of OpenPGP data succeeded\n");
170
/* Delete the GPGME FILE pointer cryptotext data buffer */
171
gpgme_data_release(dh_crypto);
417
173
/* Seek back to the beginning of the GPGME plaintext data buffer */
418
if(gpgme_data_seek(dh_plain, (off_t)0, SEEK_SET) == -1){
419
perror_plus("gpgme_data_seek");
420
plaintext_length = -1;
174
gpgme_data_seek(dh_plain, 0, SEEK_SET);
426
plaintext_capacity = incbuffer(plaintext,
427
(size_t)plaintext_length,
429
if(plaintext_capacity == 0){
430
perror_plus("incbuffer");
431
plaintext_length = -1;
178
if (new_packet_length + BUFFER_SIZE > new_packet_capacity){
179
*new_packet = realloc(*new_packet, new_packet_capacity + BUFFER_SIZE);
180
if (*new_packet == NULL){
184
new_packet_capacity += BUFFER_SIZE;
435
ret = gpgme_data_read(dh_plain, *plaintext + plaintext_length,
187
ret = gpgme_data_read(dh_plain, *new_packet + new_packet_length, BUFFER_SIZE);
437
188
/* Print the data, if any */
190
/* If password is empty, then a incorrect error will be printed */
443
perror_plus("gpgme_data_read");
444
plaintext_length = -1;
194
perror("gpgme_data_read");
447
plaintext_length += ret;
197
new_packet_length += ret;
451
fprintf_plus(stderr, "Decrypted password is: ");
452
for(ssize_t i = 0; i < plaintext_length; i++){
453
fprintf(stderr, "%02hhX ", (*plaintext)[i]);
455
fprintf(stderr, "\n");
201
fprintf(stderr, "decrypted password is: %s\n", *new_packet);
460
/* Delete the GPGME cryptotext data buffer */
461
gpgme_data_release(dh_crypto);
463
/* Delete the GPGME plaintext data buffer */
204
/* Delete the GPGME plaintext data buffer */
464
205
gpgme_data_release(dh_plain);
465
return plaintext_length;
206
return new_packet_length;
468
static const char * safer_gnutls_strerror(int value){
469
const char *ret = gnutls_strerror(value);
209
static const char * safer_gnutls_strerror (int value) {
210
const char *ret = gnutls_strerror (value);
471
212
ret = "(unknown)";
475
/* GnuTLS log function callback */
476
static void debuggnutls(__attribute__((unused)) int level,
478
fprintf_plus(stderr, "GnuTLS: %s", string);
216
void debuggnutls(int level, const char* string){
217
fprintf(stderr, "%s", string);
481
static int init_gnutls_global(const char *pubkeyfilename,
482
const char *seckeyfilename,
220
int initgnutls(encrypted_session *es){
487
fprintf_plus(stderr, "Initializing GnuTLS\n");
225
fprintf(stderr, "Initializing gnutls\n");
490
ret = gnutls_global_init();
491
if(ret != GNUTLS_E_SUCCESS){
492
fprintf_plus(stderr, "GnuTLS global_init: %s\n",
493
safer_gnutls_strerror(ret));
229
if ((ret = gnutls_global_init ())
230
!= GNUTLS_E_SUCCESS) {
231
fprintf (stderr, "global_init: %s\n", safer_gnutls_strerror(ret));
498
/* "Use a log level over 10 to enable all debugging options."
501
236
gnutls_global_set_log_level(11);
502
237
gnutls_global_set_log_function(debuggnutls);
505
/* OpenPGP credentials */
506
ret = gnutls_certificate_allocate_credentials(&mc->cred);
507
if(ret != GNUTLS_E_SUCCESS){
508
fprintf_plus(stderr, "GnuTLS memory error: %s\n",
509
safer_gnutls_strerror(ret));
510
gnutls_global_deinit();
241
/* openpgp credentials */
242
if ((ret = gnutls_certificate_allocate_credentials (&es->cred))
243
!= GNUTLS_E_SUCCESS) {
244
fprintf (stderr, "memory error: %s\n", safer_gnutls_strerror(ret));
515
fprintf_plus(stderr, "Attempting to use OpenPGP public key %s and"
516
" secret key %s as GnuTLS credentials\n",
249
fprintf(stderr, "Attempting to use openpgp certificate %s"
250
" and keyfile %s as gnutls credentials\n", CERTFILE, KEYFILE);
521
253
ret = gnutls_certificate_set_openpgp_key_file
522
(mc->cred, pubkeyfilename, seckeyfilename,
523
GNUTLS_OPENPGP_FMT_BASE64);
524
if(ret != GNUTLS_E_SUCCESS){
526
"Error[%d] while reading the OpenPGP key pair ('%s',"
527
" '%s')\n", ret, pubkeyfilename, seckeyfilename);
528
fprintf_plus(stderr, "The GnuTLS error is: %s\n",
529
safer_gnutls_strerror(ret));
533
/* GnuTLS server initialization */
534
ret = gnutls_dh_params_init(&mc->dh_params);
535
if(ret != GNUTLS_E_SUCCESS){
536
fprintf_plus(stderr, "Error in GnuTLS DH parameter"
537
" initialization: %s\n",
538
safer_gnutls_strerror(ret));
541
ret = gnutls_dh_params_generate2(mc->dh_params, mc->dh_bits);
542
if(ret != GNUTLS_E_SUCCESS){
543
fprintf_plus(stderr, "Error in GnuTLS prime generation: %s\n",
544
safer_gnutls_strerror(ret));
548
gnutls_certificate_set_dh_params(mc->cred, mc->dh_params);
554
gnutls_certificate_free_credentials(mc->cred);
555
gnutls_global_deinit();
556
gnutls_dh_params_deinit(mc->dh_params);
560
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);
254
(es->cred, CERTFILE, KEYFILE, GNUTLS_OPENPGP_FMT_BASE64);
255
if (ret != GNUTLS_E_SUCCESS) {
257
(stderr, "Error[%d] while reading the OpenPGP key pair ('%s', '%s')\n",
258
ret, CERTFILE, KEYFILE);
259
fprintf(stdout, "The Error is: %s\n",
260
safer_gnutls_strerror(ret));
264
//Gnutls server initialization
265
if ((ret = gnutls_dh_params_init (&es->dh_params))
266
!= GNUTLS_E_SUCCESS) {
267
fprintf (stderr, "Error in dh parameter initialization: %s\n",
268
safer_gnutls_strerror(ret));
272
if ((ret = gnutls_dh_params_generate2 (es->dh_params, DH_BITS))
273
!= GNUTLS_E_SUCCESS) {
274
fprintf (stderr, "Error in prime generation: %s\n",
275
safer_gnutls_strerror(ret));
279
gnutls_certificate_set_dh_params (es->cred, es->dh_params);
281
// Gnutls session creation
282
if ((ret = gnutls_init (&es->session, GNUTLS_SERVER))
283
!= GNUTLS_E_SUCCESS){
284
fprintf(stderr, "Error in gnutls session initialization: %s\n",
285
safer_gnutls_strerror(ret));
288
if ((ret = gnutls_priority_set_direct (es->session, "NORMAL", &err))
289
!= GNUTLS_E_SUCCESS) {
290
fprintf(stderr, "Syntax error at: %s\n", err);
291
fprintf(stderr, "Gnutls error: %s\n",
292
safer_gnutls_strerror(ret));
296
if ((ret = gnutls_credentials_set
297
(es->session, GNUTLS_CRD_CERTIFICATE, es->cred))
298
!= GNUTLS_E_SUCCESS) {
299
fprintf(stderr, "Error setting a credentials set: %s\n",
300
safer_gnutls_strerror(ret));
609
304
/* ignore client certificate if any. */
610
gnutls_certificate_server_set_request(*session, GNUTLS_CERT_IGNORE);
305
gnutls_certificate_server_set_request (es->session, GNUTLS_CERT_IGNORE);
612
gnutls_dh_set_prime_bits(*session, mc->dh_bits);
307
gnutls_dh_set_prime_bits (es->session, DH_BITS);
617
/* Avahi log function callback */
618
static void empty_log(__attribute__((unused)) AvahiLogLevel level,
619
__attribute__((unused)) const char *txt){}
312
void empty_log(AvahiLogLevel level, 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,
624
int af, mandos_context *mc){
625
int ret, tcp_sd = -1;
628
struct sockaddr_in in;
629
struct sockaddr_in6 in6;
314
int start_mandos_communcation(char *ip, uint16_t port){
316
struct sockaddr_in6 to;
317
struct in6_addr ip_addr;
318
encrypted_session es;
631
319
char *buffer = NULL;
632
char *decrypted_buffer = NULL;
320
char *decrypted_buffer;
633
321
size_t buffer_length = 0;
634
322
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, mc);
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");
323
ssize_t decrypted_buffer_size;
325
const char interface[] = "eth0";
328
fprintf(stderr, "Setting up a tcp connection to %s\n", ip);
331
tcp_sd = socket(PF_INET6, SOCK_STREAM, 0);
338
fprintf(stderr, "Binding to interface %s\n", interface);
341
ret = setsockopt(tcp_sd, SOL_SOCKET, SO_BINDTODEVICE, interface, 5);
343
perror("setsockopt bindtodevice");
347
memset(&to,0,sizeof(to));
348
to.sin6_family = AF_INET6;
349
ret = inet_pton(AF_INET6, ip, &ip_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){
844
fprintf_plus(stderr, "*** GnuTLS Handshake failed ***\n");
851
/* Read OpenPGP packet that contains the wanted password */
854
fprintf_plus(stderr, "Retrieving OpenPGP encrypted password from"
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,
355
fprintf(stderr, "Bad address: %s\n", ip);
358
to.sin6_port = htons(port);
359
to.sin6_scope_id = if_nametoindex(interface);
362
fprintf(stderr, "Connection to: %s\n", ip);
365
ret = connect(tcp_sd, (struct sockaddr *) &to, sizeof(to));
371
ret = initgnutls (&es);
378
gnutls_transport_set_ptr (es.session, (gnutls_transport_ptr_t) tcp_sd);
381
fprintf(stderr, "Establishing tls session with %s\n", ip);
385
ret = gnutls_handshake (es.session);
387
if (ret != GNUTLS_E_SUCCESS){
388
fprintf(stderr, "\n*** Handshake failed ***\n");
394
//Retrieve gpg packet that contains the wanted password
397
fprintf(stderr, "Retrieving pgp encrypted password from %s\n", ip);
401
if (buffer_length + BUFFER_SIZE > buffer_capacity){
402
buffer = realloc(buffer, buffer_capacity + BUFFER_SIZE);
407
buffer_capacity += BUFFER_SIZE;
410
ret = gnutls_record_recv
411
(es.session, buffer+buffer_length, BUFFER_SIZE);
886
417
case GNUTLS_E_INTERRUPTED:
887
418
case GNUTLS_E_AGAIN:
889
420
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 "
421
ret = gnutls_handshake (es.session);
423
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);
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,
938
&decrypted_buffer, mc);
939
if(decrypted_buffer_size >= 0){
942
while(written < (size_t) decrypted_buffer_size){
948
ret = (int)fwrite(decrypted_buffer + written, 1,
949
(size_t)decrypted_buffer_size - written,
951
if(ret == 0 and ferror(stdout)){
954
fprintf_plus(stderr, "Error writing encrypted data: %s\n",
960
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);
430
fprintf(stderr, "Unknown error while reading data from encrypted session with mandos server\n");
432
gnutls_bye (es.session, GNUTLS_SHUT_RDWR);
436
buffer_length += ret;
440
if (buffer_length > 0){
441
if ((decrypted_buffer_size = gpg_packet_decrypt(buffer, buffer_length, &decrypted_buffer, CERT_ROOT)) >= 0){
442
fwrite (decrypted_buffer, 1, decrypted_buffer_size, stdout);
443
free(decrypted_buffer);
452
fprintf(stderr, "Closing tls session\n");
456
gnutls_bye (es.session, GNUTLS_SHUT_RDWR);
459
gnutls_deinit (es.session);
460
gnutls_certificate_free_credentials (es.cred);
461
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
1010
/* Called whenever a service has been resolved successfully or
1019
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
1024
(((mandos_context*)mc)->server)));
1027
case AVAHI_RESOLVER_FOUND:
1029
char ip[AVAHI_ADDRESS_STR_MAX];
1030
avahi_address_snprint(ip, sizeof(ip), address);
1032
fprintf_plus(stderr, "Mandos server \"%s\" found on %s (%s, %"
1033
PRIdMAX ") on port %" PRIu16 "\n", name,
1034
host_name, ip, (intmax_t)interface, port);
1036
int ret = start_mandos_communication(ip, (in_port_t)port,
1038
avahi_proto_to_af(proto),
1041
avahi_simple_poll_quit(simple_poll);
1043
if(not add_server(ip, (in_port_t)port, interface,
1044
avahi_proto_to_af(proto),
1045
&((mandos_context*)mc)->current_server)){
1046
fprintf_plus(stderr, "Failed to add server \"%s\" to server"
1052
avahi_s_service_resolver_free(r);
1055
static void browse_callback(AvahiSServiceBrowser *b,
1056
AvahiIfIndex interface,
1057
AvahiProtocol protocol,
1058
AvahiBrowserEvent event,
1062
AVAHI_GCC_UNUSED AvahiLookupResultFlags
1069
/* Called whenever a new services becomes available on the LAN or
1070
is removed from the LAN */
1078
case AVAHI_BROWSER_FAILURE:
1080
fprintf_plus(stderr, "(Avahi browser) %s\n",
1081
avahi_strerror(avahi_server_errno
1082
(((mandos_context*)mc)->server)));
1083
avahi_simple_poll_quit(simple_poll);
1086
case AVAHI_BROWSER_NEW:
1087
/* We ignore the returned Avahi resolver object. In the callback
1088
function we free it. If the Avahi server is terminated before
1089
the callback function is called the Avahi server will free the
1092
if(avahi_s_service_resolver_new(((mandos_context*)mc)->server,
1093
interface, protocol, name, type,
1094
domain, protocol, 0,
1095
resolve_callback, mc) == NULL)
1096
fprintf_plus(stderr, "Avahi: Failed to resolve service '%s':"
1098
avahi_strerror(avahi_server_errno
1099
(((mandos_context*)mc)->server)));
1102
case AVAHI_BROWSER_REMOVE:
1105
case AVAHI_BROWSER_ALL_FOR_NOW:
1106
case AVAHI_BROWSER_CACHE_EXHAUSTED:
1108
fprintf_plus(stderr, "No Mandos server found, still"
1115
/* Signal handler that stops main loop after SIGTERM */
1116
static void handle_sigterm(int sig){
1121
signal_received = sig;
1122
int old_errno = errno;
1123
/* set main loop to exit */
1124
if(simple_poll != NULL){
1125
avahi_simple_poll_quit(simple_poll);
1130
bool get_flags(const char *ifname, struct ifreq *ifr){
1134
int s = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1137
perror_plus("socket");
1141
strcpy(ifr->ifr_name, ifname);
1142
ret = ioctl(s, SIOCGIFFLAGS, ifr);
1146
perror_plus("ioctl SIOCGIFFLAGS");
1154
bool good_flags(const char *ifname, const struct ifreq *ifr){
1156
/* Reject the loopback device */
1157
if(ifr->ifr_flags & IFF_LOOPBACK){
1159
fprintf_plus(stderr, "Rejecting loopback interface \"%s\"\n",
1164
/* Accept point-to-point devices only if connect_to is specified */
1165
if(connect_to != NULL and (ifr->ifr_flags & IFF_POINTOPOINT)){
1167
fprintf_plus(stderr, "Accepting point-to-point interface"
1168
" \"%s\"\n", ifname);
1172
/* Otherwise, reject non-broadcast-capable devices */
1173
if(not (ifr->ifr_flags & IFF_BROADCAST)){
1175
fprintf_plus(stderr, "Rejecting non-broadcast interface"
1176
" \"%s\"\n", ifname);
1180
/* Reject non-ARP interfaces (including dummy interfaces) */
1181
if(ifr->ifr_flags & IFF_NOARP){
1183
fprintf_plus(stderr, "Rejecting non-ARP interface \"%s\"\n",
1189
/* Accept this device */
1191
fprintf_plus(stderr, "Interface \"%s\" is good\n", ifname);
1197
* This function determines if a directory entry in /sys/class/net
1198
* corresponds to an acceptable network device.
1199
* (This function is passed to scandir(3) as a filter function.)
1201
int good_interface(const struct dirent *if_entry){
1202
if(if_entry->d_name[0] == '.'){
1207
if(not get_flags(if_entry->d_name, &ifr)){
1209
fprintf_plus(stderr, "Failed to get flags for interface "
1210
"\"%s\"\n", if_entry->d_name);
1215
if(not good_flags(if_entry->d_name, &ifr)){
1222
* This function determines if a network interface is up.
1224
bool interface_is_up(const char *interface){
1226
if(not get_flags(interface, &ifr)){
1228
fprintf_plus(stderr, "Failed to get flags for interface "
1229
"\"%s\"\n", interface);
1234
return (bool)(ifr.ifr_flags & IFF_UP);
1238
* This function determines if a network interface is running
1240
bool interface_is_running(const char *interface){
1242
if(not get_flags(interface, &ifr)){
1244
fprintf_plus(stderr, "Failed to get flags for interface "
1245
"\"%s\"\n", interface);
1250
return (bool)(ifr.ifr_flags & IFF_RUNNING);
1253
int notdotentries(const struct dirent *direntry){
1254
/* Skip "." and ".." */
1255
if(direntry->d_name[0] == '.'
1256
and (direntry->d_name[1] == '\0'
1257
or (direntry->d_name[1] == '.'
1258
and direntry->d_name[2] == '\0'))){
1264
/* Is this directory entry a runnable program? */
1265
int runnable_hook(const struct dirent *direntry){
1270
if((direntry->d_name)[0] == '\0'){
1275
sret = strspn(direntry->d_name, "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
1276
"abcdefghijklmnopqrstuvwxyz"
1279
if((direntry->d_name)[sret] != '\0'){
1280
/* Contains non-allowed characters */
1282
fprintf_plus(stderr, "Ignoring hook \"%s\" with bad name\n",
1288
char *fullname = NULL;
1289
ret = asprintf(&fullname, "%s/%s", hookdir, direntry->d_name);
1291
perror_plus("asprintf");
1295
ret = stat(fullname, &st);
1298
perror_plus("Could not stat hook");
1302
if(not (S_ISREG(st.st_mode))){
1303
/* Not a regular file */
1305
fprintf_plus(stderr, "Ignoring hook \"%s\" - not a file\n",
1310
if(not (st.st_mode & (S_IXUSR | S_IXGRP | S_IXOTH))){
1311
/* Not executable */
1313
fprintf_plus(stderr, "Ignoring hook \"%s\" - not executable\n",
1319
fprintf_plus(stderr, "Hook \"%s\" is acceptable\n",
1325
int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,
1326
mandos_context *mc){
1328
struct timespec now;
1329
struct timespec waited_time;
1330
intmax_t block_time;
1333
if(mc->current_server == NULL){
1335
fprintf_plus(stderr, "Wait until first server is found."
1338
ret = avahi_simple_poll_iterate(s, -1);
1341
fprintf_plus(stderr, "Check current_server if we should run"
1344
/* the current time */
1345
ret = clock_gettime(CLOCK_MONOTONIC, &now);
1347
perror_plus("clock_gettime");
1350
/* Calculating in ms how long time between now and server
1351
who we visted longest time ago. Now - last seen. */
1352
waited_time.tv_sec = (now.tv_sec
1353
- mc->current_server->last_seen.tv_sec);
1354
waited_time.tv_nsec = (now.tv_nsec
1355
- mc->current_server->last_seen.tv_nsec);
1356
/* total time is 10s/10,000ms.
1357
Converting to s from ms by dividing by 1,000,
1358
and ns to ms by dividing by 1,000,000. */
1359
block_time = ((retry_interval
1360
- ((intmax_t)waited_time.tv_sec * 1000))
1361
- ((intmax_t)waited_time.tv_nsec / 1000000));
1364
fprintf_plus(stderr, "Blocking for %" PRIdMAX " ms\n",
1368
if(block_time <= 0){
1369
ret = start_mandos_communication(mc->current_server->ip,
1370
mc->current_server->port,
1371
mc->current_server->if_index,
1372
mc->current_server->af, mc);
1374
avahi_simple_poll_quit(s);
1377
ret = clock_gettime(CLOCK_MONOTONIC,
1378
&mc->current_server->last_seen);
1380
perror_plus("clock_gettime");
1383
mc->current_server = mc->current_server->next;
1384
block_time = 0; /* Call avahi to find new Mandos
1385
servers, but don't block */
1388
ret = avahi_simple_poll_iterate(s, (int)block_time);
1391
if (ret > 0 or errno != EINTR){
1392
return (ret != 1) ? ret : 0;
1398
/* Set effective uid to 0, return errno */
1399
error_t raise_privileges(void){
1400
error_t old_errno = errno;
1401
error_t ret_errno = 0;
1402
if(seteuid(0) == -1){
1404
perror_plus("seteuid");
1410
/* Set effective and real user ID to 0. Return errno. */
1411
error_t raise_privileges_permanently(void){
1412
error_t old_errno = errno;
1413
error_t ret_errno = raise_privileges();
1418
if(setuid(0) == -1){
1420
perror_plus("seteuid");
1426
/* Set effective user ID to unprivileged saved user ID */
1427
error_t lower_privileges(void){
1428
error_t old_errno = errno;
1429
error_t ret_errno = 0;
1430
if(seteuid(uid) == -1){
1432
perror_plus("seteuid");
1438
/* Lower privileges permanently */
1439
error_t lower_privileges_permanently(void){
1440
error_t old_errno = errno;
1441
error_t ret_errno = 0;
1442
if(setuid(uid) == -1){
1444
perror_plus("setuid");
1450
bool run_network_hooks(const char *mode, const char *interface,
1452
struct dirent **direntries;
1453
struct dirent *direntry;
1455
int numhooks = scandir(hookdir, &direntries, runnable_hook,
1458
if(errno == ENOENT){
1460
fprintf_plus(stderr, "Network hook directory \"%s\" not"
1461
" found\n", hookdir);
1464
perror_plus("scandir");
1467
int devnull = open("/dev/null", O_RDONLY);
1468
for(int i = 0; i < numhooks; i++){
1469
direntry = direntries[i];
1470
char *fullname = NULL;
1471
ret = asprintf(&fullname, "%s/%s", hookdir, direntry->d_name);
1473
perror_plus("asprintf");
1477
fprintf_plus(stderr, "Running network hook \"%s\"\n",
1480
pid_t hook_pid = fork();
1483
/* Raise privileges */
1484
raise_privileges_permanently();
1489
perror_plus("setgid");
1491
/* Reset supplementary groups */
1493
ret = setgroups(0, NULL);
1495
perror_plus("setgroups");
1497
dup2(devnull, STDIN_FILENO);
1499
dup2(STDERR_FILENO, STDOUT_FILENO);
1500
ret = setenv("MANDOSNETHOOKDIR", hookdir, 1);
1502
perror_plus("setenv");
1505
ret = setenv("DEVICE", interface, 1);
1507
perror_plus("setenv");
1510
ret = setenv("VERBOSITY", debug ? "1" : "0", 1);
1512
perror_plus("setenv");
1515
ret = setenv("MODE", mode, 1);
1517
perror_plus("setenv");
1521
ret = asprintf(&delaystring, "%f", delay);
1523
perror_plus("asprintf");
1526
ret = setenv("DELAY", delaystring, 1);
1529
perror_plus("setenv");
1533
if(connect_to != NULL){
1534
ret = setenv("CONNECT", connect_to, 1);
1536
perror_plus("setenv");
1540
if(execl(fullname, direntry->d_name, mode, NULL) == -1){
1541
perror_plus("execl");
1542
_exit(EXIT_FAILURE);
1546
if(TEMP_FAILURE_RETRY(waitpid(hook_pid, &status, 0)) == -1){
1547
perror_plus("waitpid");
1551
if(WIFEXITED(status)){
1552
if(WEXITSTATUS(status) != 0){
1553
fprintf_plus(stderr, "Warning: network hook \"%s\" exited"
1554
" with status %d\n", direntry->d_name,
1555
WEXITSTATUS(status));
1559
} else if(WIFSIGNALED(status)){
1560
fprintf_plus(stderr, "Warning: network hook \"%s\" died by"
1561
" signal %d\n", direntry->d_name,
1566
fprintf_plus(stderr, "Warning: network hook \"%s\""
1567
" crashed\n", direntry->d_name);
1574
fprintf_plus(stderr, "Network hook \"%s\" ran successfully\n",
1583
error_t bring_up_interface(const char *const interface,
1586
error_t old_errno = errno;
1587
error_t ret_errno = 0;
1588
int ret, ret_setflags;
1589
struct ifreq network;
1590
unsigned int if_index = if_nametoindex(interface);
1592
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
1602
if(not interface_is_up(interface)){
1603
if(not get_flags(interface, &network) and debug){
1605
fprintf_plus(stderr, "Failed to get flags for interface "
1606
"\"%s\"\n", interface);
1609
network.ifr_flags |= IFF_UP;
1611
sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1614
perror_plus("socket");
1626
fprintf_plus(stderr, "Bringing up interface \"%s\"\n",
1630
/* Raise priviliges */
1634
/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO
1635
messages about the network interface to mess up the prompt */
1636
int ret_linux = klogctl(8, NULL, 5);
1637
bool restore_loglevel = true;
1638
if(ret_linux == -1){
1639
restore_loglevel = false;
1640
perror_plus("klogctl");
1642
#endif /* __linux__ */
1643
ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
1646
if(restore_loglevel){
1647
ret_linux = klogctl(7, NULL, 0);
1648
if(ret_linux == -1){
1649
perror_plus("klogctl");
1652
#endif /* __linux__ */
1654
/* Lower privileges */
1657
/* Close the socket */
1658
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1660
perror_plus("close");
1663
if(ret_setflags == -1){
1665
perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");
1670
fprintf_plus(stderr, "Interface \"%s\" is already up; good\n",
1674
/* Sleep checking until interface is running.
1675
Check every 0.25s, up to total time of delay */
1676
for(int i=0; i < delay * 4; i++){
1677
if(interface_is_running(interface)){
1680
struct timespec sleeptime = { .tv_nsec = 250000000 };
1681
ret = nanosleep(&sleeptime, NULL);
1682
if(ret == -1 and errno != EINTR){
1683
perror_plus("nanosleep");
1691
error_t take_down_interface(const char *const interface){
1693
error_t old_errno = errno;
1694
error_t ret_errno = 0;
1695
int ret, ret_setflags;
1696
struct ifreq network;
1697
unsigned int if_index = if_nametoindex(interface);
1699
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
1703
if(interface_is_up(interface)){
1704
if(not get_flags(interface, &network) and debug){
1706
fprintf_plus(stderr, "Failed to get flags for interface "
1707
"\"%s\"\n", interface);
1710
network.ifr_flags &= ~(short)IFF_UP; /* clear flag */
1712
sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1715
perror_plus("socket");
1721
fprintf_plus(stderr, "Taking down interface \"%s\"\n",
1725
/* Raise priviliges */
1728
ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
1731
/* Lower privileges */
1734
/* Close the socket */
1735
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1737
perror_plus("close");
1740
if(ret_setflags == -1){
1742
perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");
1747
fprintf_plus(stderr, "Interface \"%s\" is already down; odd\n",
1755
int main(int argc, char *argv[]){
1756
mandos_context mc = { .server = NULL, .dh_bits = 1024,
1757
.priority = "SECURE256:!CTYPE-X.509:"
1758
"+CTYPE-OPENPGP", .current_server = NULL };
1759
AvahiSServiceBrowser *sb = NULL;
1764
int exitcode = EXIT_SUCCESS;
1765
char *interfaces = NULL;
1766
size_t interfaces_size = 0;
1767
char *interfaces_to_take_down = NULL;
1768
size_t interfaces_to_take_down_size = 0;
1769
char tempdir[] = "/tmp/mandosXXXXXX";
1770
bool tempdir_created = false;
1771
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
1772
const char *seckey = PATHDIR "/" SECKEY;
1773
const char *pubkey = PATHDIR "/" PUBKEY;
1774
char *interfaces_hooks = NULL;
1775
size_t interfaces_hooks_size = 0;
1777
bool gnutls_initialized = false;
1778
bool gpgme_initialized = false;
1780
double retry_interval = 10; /* 10s between trying a server and
1781
retrying the same server again */
1783
struct sigaction old_sigterm_action = { .sa_handler = SIG_DFL };
1784
struct sigaction sigterm_action = { .sa_handler = handle_sigterm };
1789
/* Lower any group privileges we might have, just to be safe */
1793
perror_plus("setgid");
1796
/* Lower user privileges (temporarily) */
1800
perror_plus("seteuid");
1808
struct argp_option options[] = {
1809
{ .name = "debug", .key = 128,
1810
.doc = "Debug mode", .group = 3 },
1811
{ .name = "connect", .key = 'c',
1812
.arg = "ADDRESS:PORT",
1813
.doc = "Connect directly to a specific Mandos server",
1815
{ .name = "interface", .key = 'i',
1817
.doc = "Network interface that will be used to search for"
1820
{ .name = "seckey", .key = 's',
1822
.doc = "OpenPGP secret key file base name",
1824
{ .name = "pubkey", .key = 'p',
1826
.doc = "OpenPGP public key file base name",
1828
{ .name = "dh-bits", .key = 129,
1830
.doc = "Bit length of the prime number used in the"
1831
" Diffie-Hellman key exchange",
1833
{ .name = "priority", .key = 130,
1835
.doc = "GnuTLS priority string for the TLS handshake",
1837
{ .name = "delay", .key = 131,
1839
.doc = "Maximum delay to wait for interface startup",
1841
{ .name = "retry", .key = 132,
1843
.doc = "Retry interval used when denied by the Mandos server",
1845
{ .name = "network-hook-dir", .key = 133,
1847
.doc = "Directory where network hooks are located",
1850
* These reproduce what we would get without ARGP_NO_HELP
1852
{ .name = "help", .key = '?',
1853
.doc = "Give this help list", .group = -1 },
1854
{ .name = "usage", .key = -3,
1855
.doc = "Give a short usage message", .group = -1 },
1856
{ .name = "version", .key = 'V',
1857
.doc = "Print program version", .group = -1 },
1861
error_t parse_opt(int key, char *arg,
1862
struct argp_state *state){
1865
case 128: /* --debug */
1868
case 'c': /* --connect */
1871
case 'i': /* --interface */
1872
ret_errno = argz_add_sep(&interfaces, &interfaces_size, arg,
1875
argp_error(state, "%s", strerror(ret_errno));
1878
case 's': /* --seckey */
1881
case 'p': /* --pubkey */
1884
case 129: /* --dh-bits */
1886
tmpmax = strtoimax(arg, &tmp, 10);
1887
if(errno != 0 or tmp == arg or *tmp != '\0'
1888
or tmpmax != (typeof(mc.dh_bits))tmpmax){
1889
argp_error(state, "Bad number of DH bits");
1891
mc.dh_bits = (typeof(mc.dh_bits))tmpmax;
1893
case 130: /* --priority */
1896
case 131: /* --delay */
1898
delay = strtof(arg, &tmp);
1899
if(errno != 0 or tmp == arg or *tmp != '\0'){
1900
argp_error(state, "Bad delay");
1902
case 132: /* --retry */
1904
retry_interval = strtod(arg, &tmp);
1905
if(errno != 0 or tmp == arg or *tmp != '\0'
1906
or (retry_interval * 1000) > INT_MAX
1907
or retry_interval < 0){
1908
argp_error(state, "Bad retry interval");
1911
case 133: /* --network-hook-dir */
1915
* These reproduce what we would get without ARGP_NO_HELP
1917
case '?': /* --help */
1918
argp_state_help(state, state->out_stream,
1919
(ARGP_HELP_STD_HELP | ARGP_HELP_EXIT_ERR)
1920
& ~(unsigned int)ARGP_HELP_EXIT_OK);
1921
case -3: /* --usage */
1922
argp_state_help(state, state->out_stream,
1923
ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);
1924
case 'V': /* --version */
1925
fprintf_plus(state->out_stream, "%s\n", argp_program_version);
1926
exit(argp_err_exit_status);
1929
return ARGP_ERR_UNKNOWN;
1934
struct argp argp = { .options = options, .parser = parse_opt,
1936
.doc = "Mandos client -- Get and decrypt"
1937
" passwords from a Mandos server" };
1938
ret = argp_parse(&argp, argc, argv,
1939
ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);
1946
perror_plus("argp_parse");
1947
exitcode = EX_OSERR;
1950
exitcode = EX_USAGE;
1956
/* Work around Debian bug #633582:
1957
<http://bugs.debian.org/633582> */
1959
/* Re-raise priviliges */
1960
if(raise_privileges() == 0){
1963
if(strcmp(seckey, PATHDIR "/" SECKEY) == 0){
1964
int seckey_fd = open(seckey, O_RDONLY);
1965
if(seckey_fd == -1){
1966
perror_plus("open");
1968
ret = (int)TEMP_FAILURE_RETRY(fstat(seckey_fd, &st));
1970
perror_plus("fstat");
1972
if(S_ISREG(st.st_mode)
1973
and st.st_uid == 0 and st.st_gid == 0){
1974
ret = fchown(seckey_fd, uid, gid);
1976
perror_plus("fchown");
1980
TEMP_FAILURE_RETRY(close(seckey_fd));
1984
if(strcmp(pubkey, PATHDIR "/" PUBKEY) == 0){
1985
int pubkey_fd = open(pubkey, O_RDONLY);
1986
if(pubkey_fd == -1){
1987
perror_plus("open");
1989
ret = (int)TEMP_FAILURE_RETRY(fstat(pubkey_fd, &st));
1991
perror_plus("fstat");
1993
if(S_ISREG(st.st_mode)
1994
and st.st_uid == 0 and st.st_gid == 0){
1995
ret = fchown(pubkey_fd, uid, gid);
1997
perror_plus("fchown");
2001
TEMP_FAILURE_RETRY(close(pubkey_fd));
2005
/* Lower privileges */
2009
perror_plus("seteuid");
2014
/* Remove empty interface names */
2016
char *interface = NULL;
2017
while((interface = argz_next(interfaces, interfaces_size,
2019
if(if_nametoindex(interface) == 0){
2020
if(interface[0] != '\0' and strcmp(interface, "none") != 0){
2021
fprintf_plus(stderr, "Not using nonexisting interface"
2022
" \"%s\"\n", interface);
2024
argz_delete(&interfaces, &interfaces_size, interface);
2030
/* Run network hooks */
2033
if(interfaces != NULL){
2034
interfaces_hooks = malloc(interfaces_size);
2035
if(interfaces_hooks == NULL){
2036
perror_plus("malloc");
2039
memcpy(interfaces_hooks, interfaces, interfaces_size);
2040
interfaces_hooks_size = interfaces_size;
2041
argz_stringify(interfaces_hooks, interfaces_hooks_size,
2044
if(not run_network_hooks("start", interfaces_hooks != NULL ?
2045
interfaces_hooks : "", delay)){
2051
avahi_set_log_function(empty_log);
2054
/* Initialize Avahi early so avahi_simple_poll_quit() can be called
2055
from the signal handler */
2056
/* Initialize the pseudo-RNG for Avahi */
2057
srand((unsigned int) time(NULL));
2058
simple_poll = avahi_simple_poll_new();
2059
if(simple_poll == NULL){
2060
fprintf_plus(stderr,
2061
"Avahi: Failed to create simple poll object.\n");
2062
exitcode = EX_UNAVAILABLE;
2066
sigemptyset(&sigterm_action.sa_mask);
2067
ret = sigaddset(&sigterm_action.sa_mask, SIGINT);
2069
perror_plus("sigaddset");
2070
exitcode = EX_OSERR;
2073
ret = sigaddset(&sigterm_action.sa_mask, SIGHUP);
2075
perror_plus("sigaddset");
2076
exitcode = EX_OSERR;
2079
ret = sigaddset(&sigterm_action.sa_mask, SIGTERM);
2081
perror_plus("sigaddset");
2082
exitcode = EX_OSERR;
2085
/* Need to check if the handler is SIG_IGN before handling:
2086
| [[info:libc:Initial Signal Actions]] |
2087
| [[info:libc:Basic Signal Handling]] |
2089
ret = sigaction(SIGINT, NULL, &old_sigterm_action);
2091
perror_plus("sigaction");
2094
if(old_sigterm_action.sa_handler != SIG_IGN){
2095
ret = sigaction(SIGINT, &sigterm_action, NULL);
2097
perror_plus("sigaction");
2098
exitcode = EX_OSERR;
2102
ret = sigaction(SIGHUP, NULL, &old_sigterm_action);
2104
perror_plus("sigaction");
2107
if(old_sigterm_action.sa_handler != SIG_IGN){
2108
ret = sigaction(SIGHUP, &sigterm_action, NULL);
2110
perror_plus("sigaction");
2111
exitcode = EX_OSERR;
2115
ret = sigaction(SIGTERM, NULL, &old_sigterm_action);
2117
perror_plus("sigaction");
2120
if(old_sigterm_action.sa_handler != SIG_IGN){
2121
ret = sigaction(SIGTERM, &sigterm_action, NULL);
2123
perror_plus("sigaction");
2124
exitcode = EX_OSERR;
2129
/* If no interfaces were specified, make a list */
2130
if(interfaces == NULL){
2131
struct dirent **direntries;
2132
/* Look for any good interfaces */
2133
ret = scandir(sys_class_net, &direntries, good_interface,
2136
/* Add all found interfaces to interfaces list */
2137
for(int i = 0; i < ret; ++i){
2138
ret_errno = argz_add(&interfaces, &interfaces_size,
2139
direntries[i]->d_name);
2141
perror_plus("argz_add");
2145
fprintf_plus(stderr, "Will use interface \"%s\"\n",
2146
direntries[i]->d_name);
2152
fprintf_plus(stderr, "Could not find a network interface\n");
2153
exitcode = EXIT_FAILURE;
2158
/* If we only got one interface, explicitly use only that one */
2159
if(argz_count(interfaces, interfaces_size) == 1){
2161
fprintf_plus(stderr, "Using only interface \"%s\"\n",
2164
if_index = (AvahiIfIndex)if_nametoindex(interfaces);
2167
/* Bring up interfaces which are down */
2168
if(not (argz_count(interfaces, interfaces_size) == 1
2169
and strcmp(interfaces, "none") == 0)){
2170
char *interface = NULL;
2171
while((interface = argz_next(interfaces, interfaces_size,
2173
bool interface_was_up = interface_is_up(interface);
2174
ret = bring_up_interface(interface, delay);
2175
if(not interface_was_up){
2178
perror_plus("Failed to bring up interface");
2180
ret_errno = argz_add(&interfaces_to_take_down,
2181
&interfaces_to_take_down_size,
2188
interfaces_size = 0;
2189
if(debug and (interfaces_to_take_down == NULL)){
2190
fprintf_plus(stderr, "No interfaces were brought up\n");
2198
ret = init_gnutls_global(pubkey, seckey, &mc);
2200
fprintf_plus(stderr, "init_gnutls_global failed\n");
2201
exitcode = EX_UNAVAILABLE;
2204
gnutls_initialized = true;
2211
if(mkdtemp(tempdir) == NULL){
2212
perror_plus("mkdtemp");
2215
tempdir_created = true;
2221
if(not init_gpgme(pubkey, seckey, tempdir, &mc)){
2222
fprintf_plus(stderr, "init_gpgme failed\n");
2223
exitcode = EX_UNAVAILABLE;
2226
gpgme_initialized = true;
2233
if(connect_to != NULL){
2234
/* Connect directly, do not use Zeroconf */
2235
/* (Mainly meant for debugging) */
2236
char *address = strrchr(connect_to, ':');
2238
if(address == NULL){
2239
fprintf_plus(stderr, "No colon in address\n");
2240
exitcode = EX_USAGE;
2250
tmpmax = strtoimax(address+1, &tmp, 10);
2251
if(errno != 0 or tmp == address+1 or *tmp != '\0'
2252
or tmpmax != (in_port_t)tmpmax){
2253
fprintf_plus(stderr, "Bad port number\n");
2254
exitcode = EX_USAGE;
2262
port = (in_port_t)tmpmax;
2264
/* Colon in address indicates IPv6 */
2266
if(strchr(connect_to, ':') != NULL){
2268
/* Accept [] around IPv6 address - see RFC 5952 */
2269
if(connect_to[0] == '[' and address[-1] == ']')
2277
address = connect_to;
2283
while(not quit_now){
2284
ret = start_mandos_communication(address, port, if_index, af,
2286
if(quit_now or ret == 0){
2290
fprintf_plus(stderr, "Retrying in %d seconds\n",
2291
(int)retry_interval);
2293
sleep((int)retry_interval);
2297
exitcode = EXIT_SUCCESS;
465
static AvahiSimplePoll *simple_poll = NULL;
466
static AvahiServer *server = NULL;
468
static void resolve_callback(
469
AvahiSServiceResolver *r,
470
AVAHI_GCC_UNUSED AvahiIfIndex interface,
471
AVAHI_GCC_UNUSED AvahiProtocol protocol,
472
AvahiResolverEvent event,
476
const char *host_name,
477
const AvahiAddress *address,
479
AvahiStringList *txt,
480
AvahiLookupResultFlags flags,
481
AVAHI_GCC_UNUSED void* userdata) {
485
/* Called whenever a service has been resolved successfully or timed out */
488
case AVAHI_RESOLVER_FAILURE:
489
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)));
492
case AVAHI_RESOLVER_FOUND: {
493
char ip[AVAHI_ADDRESS_STR_MAX];
494
avahi_address_snprint(ip, sizeof(ip), address);
496
fprintf(stderr, "Mandos server found at %s on port %d\n", ip, port);
498
int ret = start_mandos_communcation(ip, port);
506
avahi_s_service_resolver_free(r);
509
static void browse_callback(
510
AvahiSServiceBrowser *b,
511
AvahiIfIndex interface,
512
AvahiProtocol protocol,
513
AvahiBrowserEvent event,
517
AVAHI_GCC_UNUSED AvahiLookupResultFlags flags,
520
AvahiServer *s = userdata;
523
/* Called whenever a new services becomes available on the LAN or is removed from the LAN */
527
case AVAHI_BROWSER_FAILURE:
529
fprintf(stderr, "(Browser) %s\n", avahi_strerror(avahi_server_errno(server)));
530
avahi_simple_poll_quit(simple_poll);
533
case AVAHI_BROWSER_NEW:
534
/* We ignore the returned resolver object. In the callback
535
function we free it. If the server is terminated before
536
the callback function is called the server will free
537
the resolver for us. */
539
if (!(avahi_s_service_resolver_new(s, interface, protocol, name, type, domain, AVAHI_PROTO_INET6, 0, resolve_callback, s)))
540
fprintf(stderr, "Failed to resolve service '%s': %s\n", name, avahi_strerror(avahi_server_errno(s)));
544
case AVAHI_BROWSER_REMOVE:
547
case AVAHI_BROWSER_ALL_FOR_NOW:
548
case AVAHI_BROWSER_CACHE_EXHAUSTED:
553
int main(AVAHI_GCC_UNUSED int argc, AVAHI_GCC_UNUSED char*argv[]) {
2308
554
AvahiServerConfig config;
2309
/* Do not publish any local Zeroconf records */
555
AvahiSServiceBrowser *sb = NULL;
556
const char db[] = "--debug";
559
int returncode = EXIT_SUCCESS;
560
char *basename = rindex(argv[0], '/');
561
if(basename == NULL){
567
char *program_name = malloc(strlen(basename) + sizeof(db));
569
if (program_name == NULL){
574
program_name[0] = '\0';
576
for (int i = 1; i < argc; i++){
577
if (not strncmp(argv[i], db, 5)){
578
strcat(strcat(strcat(program_name, db ), "="), basename);
579
if(not strcmp(argv[i], db) or not strcmp(argv[i], program_name)){
587
avahi_set_log_function(empty_log);
590
/* Initialize the psuedo-RNG */
593
/* Allocate main loop object */
594
if (!(simple_poll = avahi_simple_poll_new())) {
595
fprintf(stderr, "Failed to create simple poll object.\n");
600
/* Do not publish any local records */
2310
601
avahi_server_config_init(&config);
2311
602
config.publish_hinfo = 0;
2312
603
config.publish_addresses = 0;
2313
604
config.publish_workstation = 0;
2314
605
config.publish_domain = 0;
2316
607
/* Allocate a new server */
2317
mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),
2318
&config, NULL, NULL, &ret_errno);
2320
/* Free the Avahi configuration data */
608
server = avahi_server_new(avahi_simple_poll_get(simple_poll), &config, NULL, NULL, &error);
610
/* Free the configuration data */
2321
611
avahi_server_config_free(&config);
2324
/* Check if creating the Avahi server object succeeded */
2325
if(mc.server == NULL){
2326
fprintf_plus(stderr, "Failed to create Avahi server: %s\n",
2327
avahi_strerror(ret_errno));
2328
exitcode = EX_UNAVAILABLE;
2336
/* Create the Avahi service browser */
2337
sb = avahi_s_service_browser_new(mc.server, if_index,
2338
AVAHI_PROTO_UNSPEC, "_mandos._tcp",
2339
NULL, 0, browse_callback,
2342
fprintf_plus(stderr, "Failed to create service browser: %s\n",
2343
avahi_strerror(avahi_server_errno(mc.server)));
2344
exitcode = EX_UNAVAILABLE;
2352
/* Run the main loop */
2355
fprintf_plus(stderr, "Starting Avahi loop search\n");
2358
ret = avahi_loop_with_timeout(simple_poll,
2359
(int)(retry_interval * 1000), &mc);
2361
fprintf_plus(stderr, "avahi_loop_with_timeout exited %s\n",
2362
(ret == 0) ? "successfully" : "with error");
2368
fprintf_plus(stderr, "%s exiting\n", argv[0]);
2371
/* Cleanup things */
2373
avahi_s_service_browser_free(sb);
2375
if(mc.server != NULL)
2376
avahi_server_free(mc.server);
2378
if(simple_poll != NULL)
2379
avahi_simple_poll_free(simple_poll);
2381
if(gnutls_initialized){
2382
gnutls_certificate_free_credentials(mc.cred);
2383
gnutls_global_deinit();
2384
gnutls_dh_params_deinit(mc.dh_params);
2387
if(gpgme_initialized){
2388
gpgme_release(mc.ctx);
2391
/* Cleans up the circular linked list of Mandos servers the client
2393
if(mc.current_server != NULL){
2394
mc.current_server->prev->next = NULL;
2395
while(mc.current_server != NULL){
2396
server *next = mc.current_server->next;
2397
free(mc.current_server);
2398
mc.current_server = next;
2402
/* Re-raise priviliges */
2406
/* Run network hooks */
2407
run_network_hooks("stop", interfaces_hooks != NULL ?
2408
interfaces_hooks : "", delay);
2410
/* Take down the network interfaces which were brought up */
2412
char *interface = NULL;
2413
while((interface=argz_next(interfaces_to_take_down,
2414
interfaces_to_take_down_size,
2416
ret_errno = take_down_interface(interface);
2419
perror_plus("Failed to take down interface");
2422
if(debug and (interfaces_to_take_down == NULL)){
2423
fprintf_plus(stderr, "No interfaces needed to be taken"
2428
lower_privileges_permanently();
2431
free(interfaces_to_take_down);
2432
free(interfaces_hooks);
2434
/* Removes the GPGME temp directory and all files inside */
2435
if(tempdir_created){
2436
struct dirent **direntries = NULL;
2437
struct dirent *direntry = NULL;
2438
int numentries = scandir(tempdir, &direntries, notdotentries,
2440
if (numentries > 0){
2441
for(int i = 0; i < numentries; i++){
2442
direntry = direntries[i];
2443
char *fullname = NULL;
2444
ret = asprintf(&fullname, "%s/%s", tempdir,
2447
perror_plus("asprintf");
2450
ret = remove(fullname);
2452
fprintf_plus(stderr, "remove(\"%s\"): %s\n", fullname,
2459
/* need to clean even if 0 because man page doesn't specify */
2461
if (numentries == -1){
2462
perror_plus("scandir");
2464
ret = rmdir(tempdir);
2465
if(ret == -1 and errno != ENOENT){
2466
perror_plus("rmdir");
2471
sigemptyset(&old_sigterm_action.sa_mask);
2472
old_sigterm_action.sa_handler = SIG_DFL;
2473
ret = (int)TEMP_FAILURE_RETRY(sigaction(signal_received,
2474
&old_sigterm_action,
2477
perror_plus("sigaction");
2480
ret = raise(signal_received);
2481
} while(ret != 0 and errno == EINTR);
2483
perror_plus("raise");
2486
TEMP_FAILURE_RETRY(pause());
613
/* Check if creating the server object succeeded */
615
fprintf(stderr, "Failed to create server: %s\n", avahi_strerror(error));
616
returncode = EXIT_FAILURE;
620
/* Create the service browser */
621
if (!(sb = avahi_s_service_browser_new(server, if_nametoindex("eth0"), AVAHI_PROTO_INET6, "_mandos._tcp", NULL, 0, browse_callback, server))) {
622
fprintf(stderr, "Failed to create service browser: %s\n", avahi_strerror(avahi_server_errno(server)));
623
returncode = EXIT_FAILURE;
627
/* Run the main loop */
630
fprintf(stderr, "Starting avahi loop search\n");
633
avahi_simple_poll_loop(simple_poll);
638
fprintf(stderr, "%s exiting\n", argv[0]);
643
avahi_s_service_browser_free(sb);
646
avahi_server_free(server);
649
avahi_simple_poll_free(simple_poll);