26
25
* along with this program. If not, see
27
26
* <http://www.gnu.org/licenses/>.
29
* Contact the authors at <mandos@recompile.se>.
28
* Contact the authors at <mandos@fukt.bsnet.se>.
32
31
/* Needed by GPGME, specifically gpgme_data_seek() */
33
#ifndef _LARGEFILE_SOURCE
34
32
#define _LARGEFILE_SOURCE
36
#ifndef _FILE_OFFSET_BITS
37
33
#define _FILE_OFFSET_BITS 64
40
#define _GNU_SOURCE /* TEMP_FAILURE_RETRY(), asprintf() */
42
#include <stdio.h> /* fprintf(), stderr, fwrite(),
43
stdout, ferror(), remove() */
44
#include <stdint.h> /* uint16_t, uint32_t, intptr_t */
35
#define _GNU_SOURCE /* TEMP_FAILURE_RETRY() */
37
#include <stdio.h> /* fprintf(), stderr, fwrite(), stdout, ferror() */
38
#include <stdint.h> /* uint16_t, uint32_t */
45
39
#include <stddef.h> /* NULL, size_t, ssize_t */
46
#include <stdlib.h> /* free(), EXIT_SUCCESS, srand(),
48
#include <stdbool.h> /* bool, false, true */
49
#include <string.h> /* memset(), strcmp(), strlen(),
50
strerror(), asprintf(), strcpy() */
51
#include <sys/ioctl.h> /* ioctl */
40
#include <stdlib.h> /* free() */
41
#include <stdbool.h> /* bool, true */
42
#include <string.h> /* memset(), strcmp(), strlen, strerror() */
43
#include <sys/ioctl.h> /* ioctl, ifreq, SIOCGIFFLAGS, IFF_UP,
52
45
#include <sys/types.h> /* socket(), inet_pton(), sockaddr,
53
sockaddr_in6, PF_INET6,
54
SOCK_STREAM, uid_t, gid_t, open(),
56
#include <sys/stat.h> /* open(), S_ISREG */
46
sockaddr_in6, PF_INET6, SOCK_STREAM, INET6_ADDRSTRLEN */
57
47
#include <sys/socket.h> /* socket(), struct sockaddr_in6,
58
inet_pton(), connect() */
59
#include <fcntl.h> /* open() */
60
#include <dirent.h> /* opendir(), struct dirent, readdir()
62
#include <inttypes.h> /* PRIu16, PRIdMAX, intmax_t,
64
#include <errno.h> /* perror(), errno,
65
program_invocation_short_name */
66
#include <time.h> /* nanosleep(), time(), sleep() */
48
struct in6_addr, inet_pton(),
51
#include <errno.h> /* perror() */
67
53
#include <net/if.h> /* ioctl, ifreq, SIOCGIFFLAGS, IFF_UP,
68
54
SIOCSIFFLAGS, if_indextoname(),
69
55
if_nametoindex(), IF_NAMESIZE */
70
#include <netinet/in.h> /* IN6_IS_ADDR_LINKLOCAL,
71
INET_ADDRSTRLEN, INET6_ADDRSTRLEN
73
#include <unistd.h> /* close(), SEEK_SET, off_t, write(),
74
getuid(), getgid(), seteuid(),
75
setgid(), pause(), _exit() */
76
#include <arpa/inet.h> /* inet_pton(), htons, inet_ntop() */
77
#include <iso646.h> /* not, or, and */
78
#include <argp.h> /* struct argp_option, error_t, struct
79
argp_state, struct argp,
80
argp_parse(), ARGP_KEY_ARG,
81
ARGP_KEY_END, ARGP_ERR_UNKNOWN */
82
#include <signal.h> /* sigemptyset(), sigaddset(),
83
sigaction(), SIGTERM, sig_atomic_t,
85
#include <sysexits.h> /* EX_OSERR, EX_USAGE, EX_UNAVAILABLE,
86
EX_NOHOST, EX_IOERR, EX_PROTOCOL */
87
#include <sys/wait.h> /* waitpid(), WIFEXITED(),
88
WEXITSTATUS(), WTERMSIG() */
89
#include <grp.h> /* setgroups() */
90
#include <argz.h> /* argz_add_sep(), argz_next(),
91
argz_delete(), argz_append(),
92
argz_stringify(), argz_add(),
96
#include <sys/klog.h> /* klogctl() */
97
#endif /* __linux__ */
56
#include <unistd.h> /* close(), SEEK_SET, off_t, write()*/
57
#include <netinet/in.h>
58
#include <arpa/inet.h> /* inet_pton(), htons */
59
#include <iso646.h> /* not */
60
#include <argp.h> /* struct argp_option,
61
struct argp_state, struct argp,
100
/* All Avahi types, constants and functions
103
#include <avahi-core/core.h>
65
#include <avahi-core/core.h> /* AvahiSimplePoll, AvahiServer,
104
67
#include <avahi-core/lookup.h>
105
#include <avahi-core/log.h>
68
#include <avahi-core/log.h> /* AvahiLogLevel */
106
69
#include <avahi-common/simple-watch.h>
107
70
#include <avahi-common/malloc.h>
108
71
#include <avahi-common/error.h>
111
#include <gnutls/gnutls.h> /* All GnuTLS types, constants and
74
#include <gnutls/gnutls.h> /* gnutls_certificate_credentials_t,
78
gnutls_global_set_log_level(),
79
gnutls_global_set_log_function(),
80
gnutls_certificate_allocate_credentials(),
81
gnutls_global_deinit(),
82
gnutls_dh_params_init(),
83
gnutls_dh_params_generate(),
84
gnutls_certificate_set_dh_params(),
85
gnutls_certificate_free_credentials(),
86
gnutls_session_t, gnutls_init(),
87
gnutls_priority_set_direct(),
89
gnutls_credentials_set(),
90
gnutls_certificate_server_set_request(),
91
gnutls_dh_set_prime_bits(),
92
gnutls_transport_set_ptr(),
93
gnutls_transport_ptr_t,
96
gnutls_perror(), gnutls_bye(),
114
97
init_gnutls_session(),
116
#include <gnutls/openpgp.h>
117
/* gnutls_certificate_set_openpgp_key_file(),
118
GNUTLS_OPENPGP_FMT_BASE64 */
99
GNUTLS_CRD_CERTIFICATE,
101
GNUTLS_E_INTERRUPTED,
103
GNUTLS_E_REHANDSHAKE,
105
#include <gnutls/openpgp.h> /* gnutls_certificate_set_openpgp_key_file(),
106
GNUTLS_OPENPGP_FMT_BASE64 */
121
#include <gpgme.h> /* All GPGME types, constants and
109
#include <gpgme.h> /* gpgme_data_t, gpgme_ctx_t,
110
gpgme_error_t, gpgme_engine_info_t,
111
gpgme_check_version(),
112
gpgme_engine_check_version(),
115
gpgme_get_engine_info(),
116
gpgme_set_engine_info(),
117
gpgme_data_new_from_mem(),
118
gpgme_data_new(), gpgme_new(),
120
gpgme_decrypt_result_t,
121
gpgme_op_decrypt_result(),
123
gpgme_pubkey_algo_name(),
124
127
GPGME_PROTOCOL_OpenPGP,
129
GPG_ERR_NO_SECKEY, */
127
131
#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
133
bool debug = false;
134
static const char *keydir = "/conf/conf.d/mandos";
135
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;
136
const char *argp_program_version = "mandosclient 0.9";
137
const char *argp_program_bug_address = "<mandos@fukt.bsnet.se>";
155
139
/* Used for passing in values through the Avahi callback functions */
141
AvahiSimplePoll *simple_poll;
157
142
AvahiServer *server;
158
143
gnutls_certificate_credentials_t cred;
159
144
unsigned int dh_bits;
160
145
gnutls_dh_params_t dh_params;
161
146
const char *priority;
163
server *current_server;
165
size_t interfaces_size;
166
147
} mandos_context;
168
/* global so signal handler can reach it*/
169
AvahiSimplePoll *simple_poll;
171
sig_atomic_t quit_now = 0;
172
int signal_received = 0;
174
/* Function to use when printing errors */
175
void perror_plus(const char *print_text){
177
fprintf(stderr, "Mandos plugin %s: ",
178
program_invocation_short_name);
183
__attribute__((format (gnu_printf, 2, 3)))
184
int fprintf_plus(FILE *stream, const char *format, ...){
186
va_start (ap, format);
188
TEMP_FAILURE_RETRY(fprintf(stream, "Mandos plugin %s: ",
189
program_invocation_short_name));
190
return (int)TEMP_FAILURE_RETRY(vfprintf(stream, format, ap));
194
* Make additional room in "buffer" for at least BUFFER_SIZE more
195
* bytes. "buffer_capacity" is how much is currently allocated,
150
* Make room in "buffer" for at least BUFFER_SIZE additional bytes.
151
* "buffer_capacity" is how much is currently allocated,
196
152
* "buffer_length" is how much is already used.
198
size_t incbuffer(char **buffer, size_t buffer_length,
199
size_t buffer_capacity){
200
if(buffer_length + BUFFER_SIZE > buffer_capacity){
154
size_t adjustbuffer(char **buffer, size_t buffer_length,
155
size_t buffer_capacity){
156
if (buffer_length + BUFFER_SIZE > buffer_capacity){
201
157
*buffer = realloc(*buffer, buffer_capacity + BUFFER_SIZE);
205
161
buffer_capacity += BUFFER_SIZE;
207
163
return buffer_capacity;
210
/* Add server to set of servers to retry periodically */
211
bool add_server(const char *ip, in_port_t port, AvahiIfIndex if_index,
212
int af, server **current_server){
214
server *new_server = malloc(sizeof(server));
215
if(new_server == NULL){
216
perror_plus("malloc");
219
*new_server = (server){ .ip = strdup(ip),
221
.if_index = if_index,
223
if(new_server->ip == NULL){
224
perror_plus("strdup");
227
/* Special case of first server */
228
if(*current_server == NULL){
229
new_server->next = new_server;
230
new_server->prev = new_server;
231
*current_server = new_server;
232
/* Place the new server last in the list */
234
new_server->next = *current_server;
235
new_server->prev = (*current_server)->prev;
236
new_server->prev->next = new_server;
237
(*current_server)->prev = new_server;
239
ret = clock_gettime(CLOCK_MONOTONIC, &(*current_server)->last_seen);
241
perror_plus("clock_gettime");
167
* Decrypt OpenPGP data using keyrings in HOMEDIR.
168
* Returns -1 on error
250
static bool init_gpgme(const char *seckey, const char *pubkey,
251
const char *tempdir, mandos_context *mc){
170
static ssize_t pgp_packet_decrypt (const char *cryptotext,
173
const char *homedir){
174
gpgme_data_t dh_crypto, dh_plain;
252
176
gpgme_error_t rc;
178
size_t plaintext_capacity = 0;
179
ssize_t plaintext_length = 0;
253
180
gpgme_engine_info_t engine_info;
256
* Helper function to insert pub and seckey to the engine keyring.
258
bool import_key(const char *filename){
261
gpgme_data_t pgp_data;
263
fd = (int)TEMP_FAILURE_RETRY(open(filename, O_RDONLY));
269
rc = gpgme_data_new_from_fd(&pgp_data, fd);
270
if(rc != GPG_ERR_NO_ERROR){
271
fprintf_plus(stderr, "bad gpgme_data_new_from_fd: %s: %s\n",
272
gpgme_strsource(rc), gpgme_strerror(rc));
276
rc = gpgme_op_import(mc->ctx, pgp_data);
277
if(rc != GPG_ERR_NO_ERROR){
278
fprintf_plus(stderr, "bad gpgme_op_import: %s: %s\n",
279
gpgme_strsource(rc), gpgme_strerror(rc));
283
ret = (int)TEMP_FAILURE_RETRY(close(fd));
285
perror_plus("close");
287
gpgme_data_release(pgp_data);
292
fprintf_plus(stderr, "Initializing GPGME\n");
183
fprintf(stderr, "Trying to decrypt OpenPGP data\n");
296
187
gpgme_check_version(NULL);
297
188
rc = gpgme_engine_check_version(GPGME_PROTOCOL_OpenPGP);
298
if(rc != GPG_ERR_NO_ERROR){
299
fprintf_plus(stderr, "bad gpgme_engine_check_version: %s: %s\n",
300
gpgme_strsource(rc), gpgme_strerror(rc));
189
if (rc != GPG_ERR_NO_ERROR){
190
fprintf(stderr, "bad gpgme_engine_check_version: %s: %s\n",
191
gpgme_strsource(rc), gpgme_strerror(rc));
304
195
/* Set GPGME home directory for the OpenPGP engine only */
305
rc = gpgme_get_engine_info(&engine_info);
306
if(rc != GPG_ERR_NO_ERROR){
307
fprintf_plus(stderr, "bad gpgme_get_engine_info: %s: %s\n",
308
gpgme_strsource(rc), gpgme_strerror(rc));
196
rc = gpgme_get_engine_info (&engine_info);
197
if (rc != GPG_ERR_NO_ERROR){
198
fprintf(stderr, "bad gpgme_get_engine_info: %s: %s\n",
199
gpgme_strsource(rc), gpgme_strerror(rc));
311
202
while(engine_info != NULL){
312
203
if(engine_info->protocol == GPGME_PROTOCOL_OpenPGP){
313
204
gpgme_set_engine_info(GPGME_PROTOCOL_OpenPGP,
314
engine_info->file_name, tempdir);
205
engine_info->file_name, homedir);
317
208
engine_info = engine_info->next;
319
210
if(engine_info == NULL){
320
fprintf_plus(stderr, "Could not set GPGME home dir to %s\n",
325
/* Create new GPGME "context" */
326
rc = gpgme_new(&(mc->ctx));
327
if(rc != GPG_ERR_NO_ERROR){
328
fprintf_plus(stderr, "Mandos plugin mandos-client: "
329
"bad gpgme_new: %s: %s\n", gpgme_strsource(rc),
334
if(not import_key(pubkey) or not import_key(seckey)){
342
* Decrypt OpenPGP data.
343
* Returns -1 on error
345
static ssize_t pgp_packet_decrypt(const char *cryptotext,
349
gpgme_data_t dh_crypto, dh_plain;
352
size_t plaintext_capacity = 0;
353
ssize_t plaintext_length = 0;
356
fprintf_plus(stderr, "Trying to decrypt OpenPGP data\n");
211
fprintf(stderr, "Could not set GPGME home dir to %s\n", homedir);
359
215
/* Create new GPGME data buffer from memory cryptotext */
360
216
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));
218
if (rc != GPG_ERR_NO_ERROR){
219
fprintf(stderr, "bad gpgme_data_new_from_mem: %s: %s\n",
220
gpgme_strsource(rc), gpgme_strerror(rc));
368
224
/* Create new empty GPGME data buffer for the plaintext */
369
225
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));
226
if (rc != GPG_ERR_NO_ERROR){
227
fprintf(stderr, "bad gpgme_data_new: %s: %s\n",
228
gpgme_strsource(rc), gpgme_strerror(rc));
374
229
gpgme_data_release(dh_crypto);
233
/* Create new GPGME "context" */
234
rc = gpgme_new(&ctx);
235
if (rc != GPG_ERR_NO_ERROR){
236
fprintf(stderr, "bad gpgme_new: %s: %s\n",
237
gpgme_strsource(rc), gpgme_strerror(rc));
238
plaintext_length = -1;
378
242
/* 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));
244
rc = gpgme_op_decrypt(ctx, dh_crypto, dh_plain);
245
if (rc != GPG_ERR_NO_ERROR){
246
fprintf(stderr, "bad gpgme_op_decrypt: %s: %s\n",
247
gpgme_strsource(rc), gpgme_strerror(rc));
384
248
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;
253
fprintf(stderr, "Decryption of OpenPGP data succeeded\n");
257
gpgme_decrypt_result_t result;
258
result = gpgme_op_decrypt_result(ctx);
260
fprintf(stderr, "gpgme_op_decrypt_result failed\n");
262
fprintf(stderr, "Unsupported algorithm: %s\n",
263
result->unsupported_algorithm);
264
fprintf(stderr, "Wrong key usage: %d\n",
265
result->wrong_key_usage);
266
if(result->file_name != NULL){
267
fprintf(stderr, "File name: %s\n", result->file_name);
269
gpgme_recipient_t recipient;
270
recipient = result->recipients;
400
272
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
273
fprintf(stderr, "Public key algorithm: %s\n",
274
gpgme_pubkey_algo_name(recipient->pubkey_algo));
275
fprintf(stderr, "Key ID: %s\n", recipient->keyid);
276
fprintf(stderr, "Secret key available: %s\n",
277
recipient->status == GPG_ERR_NO_SECKEY
408
279
recipient = recipient->next;
416
fprintf_plus(stderr, "Decryption of OpenPGP data succeeded\n");
419
285
/* 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");
286
if (gpgme_data_seek(dh_plain, (off_t) 0, SEEK_SET) == -1){
287
perror("pgpme_data_seek");
422
288
plaintext_length = -1;
423
289
goto decrypt_end;
426
292
*plaintext = NULL;
428
plaintext_capacity = incbuffer(plaintext,
429
(size_t)plaintext_length,
431
if(plaintext_capacity == 0){
432
perror_plus("incbuffer");
433
plaintext_length = -1;
294
plaintext_capacity = adjustbuffer(plaintext,
295
(size_t)plaintext_length,
297
if (plaintext_capacity == 0){
298
perror("adjustbuffer");
299
plaintext_length = -1;
437
303
ret = gpgme_data_read(dh_plain, *plaintext + plaintext_length,
439
305
/* Print the data, if any */
445
perror_plus("gpgme_data_read");
311
perror("gpgme_data_read");
446
312
plaintext_length = -1;
447
313
goto decrypt_end;
449
315
plaintext_length += ret;
453
fprintf_plus(stderr, "Decrypted password is: ");
319
fprintf(stderr, "Decrypted password is: ");
454
320
for(ssize_t i = 0; i < plaintext_length; i++){
455
321
fprintf(stderr, "%02hhX ", (*plaintext)[i]);
621
467
__attribute__((unused)) const char *txt){}
623
469
/* Called when a Mandos server is found */
624
static int start_mandos_communication(const char *ip, in_port_t port,
470
static int start_mandos_communication(const char *ip, uint16_t port,
625
471
AvahiIfIndex if_index,
626
int af, mandos_context *mc){
627
int ret, tcp_sd = -1;
630
struct sockaddr_in in;
631
struct sockaddr_in6 in6;
474
union { struct sockaddr in; struct sockaddr_in6 in6; } to;
633
475
char *buffer = NULL;
634
char *decrypted_buffer = NULL;
476
char *decrypted_buffer;
635
477
size_t buffer_length = 0;
636
478
size_t buffer_capacity = 0;
479
ssize_t decrypted_buffer_size;
482
char interface[IF_NAMESIZE];
639
483
gnutls_session_t session;
640
int pf; /* Protocol family */
657
fprintf_plus(stderr, "Bad address family: %d\n", af);
662
/* If the interface is specified and we have a list of interfaces */
663
if(if_index != AVAHI_IF_UNSPEC and mc->interfaces != NULL){
664
/* Check if the interface is one of the interfaces we are using */
667
char *interface = NULL;
668
while((interface=argz_next(mc->interfaces, mc->interfaces_size,
670
if(if_nametoindex(interface) == (unsigned int)if_index){
677
/* This interface does not match any in the list, so we don't
678
connect to the server */
680
char interface[IF_NAMESIZE];
681
if(if_indextoname((unsigned int)if_index, interface) == NULL){
682
perror_plus("if_indextoname");
684
fprintf_plus(stderr, "Skipping server on non-used interface"
686
if_indextoname((unsigned int)if_index,
485
ret = init_gnutls_session (mc, &session);
491
fprintf(stderr, "Setting up a tcp connection to %s, port %d\n",
495
tcp_sd = socket(PF_INET6, SOCK_STREAM, 0);
502
if(if_indextoname((unsigned int)if_index, interface) == NULL){
503
perror("if_indextoname");
506
fprintf(stderr, "Binding to interface %s\n", interface);
694
ret = init_gnutls_session(&session, mc);
509
memset(&to,0,sizeof(to)); /* Spurious warning */
510
to.in6.sin6_family = AF_INET6;
511
/* It would be nice to have a way to detect if we were passed an
512
IPv4 address here. Now we assume an IPv6 address. */
513
ret = inet_pton(AF_INET6, ip, &to.in6.sin6_addr);
700
fprintf_plus(stderr, "Setting up a TCP connection to %s, port %"
701
PRIuMAX "\n", ip, (uintmax_t)port);
704
tcp_sd = socket(pf, SOCK_STREAM, 0);
707
perror_plus("socket");
717
memset(&to, 0, sizeof(to));
719
to.in6.sin6_family = (sa_family_t)af;
720
ret = inet_pton(af, ip, &to.in6.sin6_addr);
722
to.in.sin_family = (sa_family_t)af;
723
ret = inet_pton(af, ip, &to.in.sin_addr);
727
perror_plus("inet_pton");
733
fprintf_plus(stderr, "Bad address: %s\n", ip);
738
to.in6.sin6_port = htons(port);
739
if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */
740
(&to.in6.sin6_addr)){ /* -Wstrict-aliasing=2 or lower and
742
if(if_index == AVAHI_IF_UNSPEC){
743
fprintf_plus(stderr, "An IPv6 link-local address is"
744
" incomplete without a network interface\n");
748
/* Set the network interface number as scope */
749
to.in6.sin6_scope_id = (uint32_t)if_index;
752
to.in.sin_port = htons(port); /* Spurious warnings from
754
-Wunreachable-code */
519
fprintf(stderr, "Bad address: %s\n", ip);
522
to.in6.sin6_port = htons(port); /* Spurious warning */
524
to.in6.sin6_scope_id = (uint32_t)if_index;
763
if(af == AF_INET6 and if_index != AVAHI_IF_UNSPEC){
764
char interface[IF_NAMESIZE];
765
if(if_indextoname((unsigned int)if_index, interface) == NULL){
766
perror_plus("if_indextoname");
768
fprintf_plus(stderr, "Connection to: %s%%%s, port %" PRIuMAX
769
"\n", ip, interface, (uintmax_t)port);
772
fprintf_plus(stderr, "Connection to: %s, port %" PRIuMAX "\n",
773
ip, (uintmax_t)port);
775
char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?
776
INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";
779
pcret = inet_ntop(af, &(to.in6.sin6_addr), addrstr,
782
pcret = inet_ntop(af, &(to.in.sin_addr), addrstr,
786
perror_plus("inet_ntop");
527
fprintf(stderr, "Connection to: %s, port %d\n", ip, port);
528
char addrstr[INET6_ADDRSTRLEN] = "";
529
if(inet_ntop(to.in6.sin6_family, &(to.in6.sin6_addr), addrstr,
530
sizeof(addrstr)) == NULL){
788
533
if(strcmp(addrstr, ip) != 0){
789
fprintf_plus(stderr, "Canonical address form: %s\n", addrstr);
534
fprintf(stderr, "Canonical address form: %s\n", addrstr);
800
ret = connect(tcp_sd, &to.in6, sizeof(to));
802
ret = connect(tcp_sd, &to.in, sizeof(to)); /* IPv4 */
805
if ((errno != ECONNREFUSED and errno != ENETUNREACH) or debug){
807
perror_plus("connect");
539
ret = connect(tcp_sd, &to.in, sizeof(to));
818
545
const char *out = mandos_protocol_version;
821
548
size_t out_size = strlen(out);
822
ret = (int)TEMP_FAILURE_RETRY(write(tcp_sd, out + written,
823
out_size - written));
826
perror_plus("write");
549
ret = TEMP_FAILURE_RETRY(write(tcp_sd, out + written,
550
out_size - written));
830
556
written += (size_t)ret;
831
557
if(written < out_size){
834
if(out == mandos_protocol_version){
560
if (out == mandos_protocol_version){
849
fprintf_plus(stderr, "Establishing TLS session with %s\n", ip);
857
/* This casting via intptr_t is to eliminate warning about casting
858
an int to a pointer type. This is exactly how the GnuTLS Guile
859
function "set-session-transport-fd!" does it. */
860
gnutls_transport_set_ptr(session,
861
(gnutls_transport_ptr_t)(intptr_t)tcp_sd);
869
ret = gnutls_handshake(session);
874
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
876
if(ret != GNUTLS_E_SUCCESS){
570
fprintf(stderr, "Establishing TLS session with %s\n", ip);
573
gnutls_transport_set_ptr (session, (gnutls_transport_ptr_t) tcp_sd);
575
ret = gnutls_handshake (session);
577
if (ret != GNUTLS_E_SUCCESS){
878
fprintf_plus(stderr, "*** GnuTLS Handshake failed ***\n");
579
fprintf(stderr, "*** GnuTLS Handshake failed ***\n");
885
586
/* Read OpenPGP packet that contains the wanted password */
888
fprintf_plus(stderr, "Retrieving OpenPGP encrypted password from"
589
fprintf(stderr, "Retrieving pgp encrypted password from %s\n",
899
buffer_capacity = incbuffer(&buffer, buffer_length,
901
if(buffer_capacity == 0){
903
perror_plus("incbuffer");
913
sret = gnutls_record_recv(session, buffer+buffer_length,
594
buffer_capacity = adjustbuffer(&buffer, buffer_length,
596
if (buffer_capacity == 0){
597
perror("adjustbuffer");
602
ret = gnutls_record_recv(session, buffer+buffer_length,
920
609
case GNUTLS_E_INTERRUPTED:
921
610
case GNUTLS_E_AGAIN:
923
612
case GNUTLS_E_REHANDSHAKE:
925
ret = gnutls_handshake(session);
931
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
933
fprintf_plus(stderr, "*** GnuTLS Re-handshake failed "
613
ret = gnutls_handshake (session);
615
fprintf(stderr, "*** GnuTLS Re-handshake failed ***\n");
941
fprintf_plus(stderr, "Unknown error while reading data from"
942
" encrypted session with Mandos server\n");
943
gnutls_bye(session, GNUTLS_SHUT_RDWR);
622
fprintf(stderr, "Unknown error while reading data from"
623
" encrypted session with Mandos server\n");
625
gnutls_bye (session, GNUTLS_SHUT_RDWR);
948
buffer_length += (size_t) sret;
629
buffer_length += (size_t) ret;
953
fprintf_plus(stderr, "Closing TLS session\n");
962
ret = gnutls_bye(session, GNUTLS_SHUT_RDWR);
967
} while(ret == GNUTLS_E_AGAIN or ret == GNUTLS_E_INTERRUPTED);
969
if(buffer_length > 0){
970
ssize_t decrypted_buffer_size;
971
decrypted_buffer_size = pgp_packet_decrypt(buffer, buffer_length,
972
&decrypted_buffer, mc);
973
if(decrypted_buffer_size >= 0){
634
fprintf(stderr, "Closing TLS session\n");
637
gnutls_bye (session, GNUTLS_SHUT_RDWR);
639
if (buffer_length > 0){
640
decrypted_buffer_size = pgp_packet_decrypt(buffer,
644
if (decrypted_buffer_size >= 0){
976
646
while(written < (size_t) decrypted_buffer_size){
982
ret = (int)fwrite(decrypted_buffer + written, 1,
983
(size_t)decrypted_buffer_size - written,
647
ret = (int)fwrite (decrypted_buffer + written, 1,
648
(size_t)decrypted_buffer_size - written,
985
650
if(ret == 0 and ferror(stdout)){
988
fprintf_plus(stderr, "Error writing encrypted data: %s\n",
652
fprintf(stderr, "Error writing encrypted data: %s\n",
994
658
written += (size_t)ret;
660
free(decrypted_buffer);
1000
666
/* Shutdown procedure */
1005
free(decrypted_buffer);
1008
ret = (int)TEMP_FAILURE_RETRY(close(tcp_sd));
1014
perror_plus("close");
1016
gnutls_deinit(session);
671
gnutls_deinit (session);
1026
675
static void resolve_callback(AvahiSServiceResolver *r,
1027
676
AvahiIfIndex interface,
1028
AvahiProtocol proto,
677
AVAHI_GCC_UNUSED AvahiProtocol protocol,
1029
678
AvahiResolverEvent event,
1030
679
const char *name,
1031
680
const char *type,
1139
762
case AVAHI_BROWSER_ALL_FOR_NOW:
1140
763
case AVAHI_BROWSER_CACHE_EXHAUSTED:
1142
fprintf_plus(stderr, "No Mandos server found, still"
765
fprintf(stderr, "No Mandos server found, still searching...\n");
1149
/* Signal handler that stops main loop after SIGTERM */
1150
static void handle_sigterm(int sig){
1155
signal_received = sig;
1156
int old_errno = errno;
1157
/* set main loop to exit */
1158
if(simple_poll != NULL){
1159
avahi_simple_poll_quit(simple_poll);
1164
bool get_flags(const char *ifname, struct ifreq *ifr){
1168
int s = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1171
perror_plus("socket");
1175
strcpy(ifr->ifr_name, ifname);
1176
ret = ioctl(s, SIOCGIFFLAGS, ifr);
1180
perror_plus("ioctl SIOCGIFFLAGS");
1188
bool good_flags(const char *ifname, const struct ifreq *ifr){
1190
/* Reject the loopback device */
1191
if(ifr->ifr_flags & IFF_LOOPBACK){
1193
fprintf_plus(stderr, "Rejecting loopback interface \"%s\"\n",
1198
/* Accept point-to-point devices only if connect_to is specified */
1199
if(connect_to != NULL and (ifr->ifr_flags & IFF_POINTOPOINT)){
1201
fprintf_plus(stderr, "Accepting point-to-point interface"
1202
" \"%s\"\n", ifname);
1206
/* Otherwise, reject non-broadcast-capable devices */
1207
if(not (ifr->ifr_flags & IFF_BROADCAST)){
1209
fprintf_plus(stderr, "Rejecting non-broadcast interface"
1210
" \"%s\"\n", ifname);
1214
/* Reject non-ARP interfaces (including dummy interfaces) */
1215
if(ifr->ifr_flags & IFF_NOARP){
1217
fprintf_plus(stderr, "Rejecting non-ARP interface \"%s\"\n",
1223
/* Accept this device */
1225
fprintf_plus(stderr, "Interface \"%s\" is good\n", ifname);
1231
* This function determines if a directory entry in /sys/class/net
1232
* corresponds to an acceptable network device.
1233
* (This function is passed to scandir(3) as a filter function.)
1235
int good_interface(const struct dirent *if_entry){
1236
if(if_entry->d_name[0] == '.'){
1241
if(not get_flags(if_entry->d_name, &ifr)){
1243
fprintf_plus(stderr, "Failed to get flags for interface "
1244
"\"%s\"\n", if_entry->d_name);
1249
if(not good_flags(if_entry->d_name, &ifr)){
1256
* This function determines if a network interface is up.
1258
bool interface_is_up(const char *interface){
1260
if(not get_flags(interface, &ifr)){
1262
fprintf_plus(stderr, "Failed to get flags for interface "
1263
"\"%s\"\n", interface);
1268
return (bool)(ifr.ifr_flags & IFF_UP);
1272
* This function determines if a network interface is running
1274
bool interface_is_running(const char *interface){
1276
if(not get_flags(interface, &ifr)){
1278
fprintf_plus(stderr, "Failed to get flags for interface "
1279
"\"%s\"\n", interface);
1284
return (bool)(ifr.ifr_flags & IFF_RUNNING);
1287
int notdotentries(const struct dirent *direntry){
1288
/* Skip "." and ".." */
1289
if(direntry->d_name[0] == '.'
1290
and (direntry->d_name[1] == '\0'
1291
or (direntry->d_name[1] == '.'
1292
and direntry->d_name[2] == '\0'))){
1298
/* Is this directory entry a runnable program? */
1299
int runnable_hook(const struct dirent *direntry){
1304
if((direntry->d_name)[0] == '\0'){
1309
sret = strspn(direntry->d_name, "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
1310
"abcdefghijklmnopqrstuvwxyz"
1313
if((direntry->d_name)[sret] != '\0'){
1314
/* Contains non-allowed characters */
1316
fprintf_plus(stderr, "Ignoring hook \"%s\" with bad name\n",
1322
char *fullname = NULL;
1323
ret = asprintf(&fullname, "%s/%s", hookdir, direntry->d_name);
1325
perror_plus("asprintf");
1329
ret = stat(fullname, &st);
1332
perror_plus("Could not stat hook");
1336
if(not (S_ISREG(st.st_mode))){
1337
/* Not a regular file */
1339
fprintf_plus(stderr, "Ignoring hook \"%s\" - not a file\n",
1344
if(not (st.st_mode & (S_IXUSR | S_IXGRP | S_IXOTH))){
1345
/* Not executable */
1347
fprintf_plus(stderr, "Ignoring hook \"%s\" - not executable\n",
1353
fprintf_plus(stderr, "Hook \"%s\" is acceptable\n",
1359
int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,
1360
mandos_context *mc){
1362
struct timespec now;
1363
struct timespec waited_time;
1364
intmax_t block_time;
1367
if(mc->current_server == NULL){
1369
fprintf_plus(stderr, "Wait until first server is found."
771
/* Combines file name and path and returns the malloced new
772
string. some sane checks could/should be added */
773
static const char *combinepath(const char *first, const char *second){
774
size_t f_len = strlen(first);
775
size_t s_len = strlen(second);
776
char *tmp = malloc(f_len + s_len + 2);
781
memcpy(tmp, first, f_len); /* Spurious warning */
785
memcpy(tmp + f_len + 1, second, s_len); /* Spurious warning */
787
tmp[f_len + 1 + s_len] = '\0';
792
int main(int argc, char *argv[]){
793
AvahiSServiceBrowser *sb = NULL;
796
int exitcode = EXIT_SUCCESS;
797
const char *interface = "eth0";
798
struct ifreq network;
802
char *connect_to = NULL;
803
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
804
const char *pubkeyfile = "pubkey.txt";
805
const char *seckeyfile = "seckey.txt";
806
mandos_context mc = { .simple_poll = NULL, .server = NULL,
807
.dh_bits = 1024, .priority = "SECURE256"};
808
bool gnutls_initalized = false;
811
struct argp_option options[] = {
812
{ .name = "debug", .key = 128,
813
.doc = "Debug mode", .group = 3 },
814
{ .name = "connect", .key = 'c',
816
.doc = "Connect directly to a sepcified mandos server",
818
{ .name = "interface", .key = 'i',
820
.doc = "Interface that Avahi will conntect through",
822
{ .name = "keydir", .key = 'd',
824
.doc = "Directory where the openpgp keyring is",
826
{ .name = "seckey", .key = 's',
828
.doc = "Secret openpgp key for gnutls authentication",
830
{ .name = "pubkey", .key = 'p',
832
.doc = "Public openpgp key for gnutls authentication",
834
{ .name = "dh-bits", .key = 129,
836
.doc = "dh-bits to use in gnutls communication",
838
{ .name = "priority", .key = 130,
840
.doc = "GNUTLS priority", .group = 1 },
845
error_t parse_opt (int key, char *arg,
846
struct argp_state *state) {
847
/* Get the INPUT argument from `argp_parse', which we know is
848
a pointer to our plugin list pointer. */
870
mc.dh_bits = (unsigned int) strtol(arg, NULL, 10);
885
return ARGP_ERR_UNKNOWN;
1372
ret = avahi_simple_poll_iterate(s, -1);
890
struct argp argp = { .options = options, .parser = parse_opt,
892
.doc = "Mandos client -- Get and decrypt"
893
" passwords from mandos server" };
894
argp_parse (&argp, argc, argv, 0, 0, NULL);
897
pubkeyfile = combinepath(keydir, pubkeyfile);
898
if (pubkeyfile == NULL){
899
perror("combinepath");
900
exitcode = EXIT_FAILURE;
904
seckeyfile = combinepath(keydir, seckeyfile);
905
if (seckeyfile == NULL){
906
perror("combinepath");
910
ret = init_gnutls_global(&mc, pubkeyfile, seckeyfile);
912
fprintf(stderr, "init_gnutls_global\n");
1375
fprintf_plus(stderr, "Check current_server if we should run"
1378
/* the current time */
1379
ret = clock_gettime(CLOCK_MONOTONIC, &now);
915
gnutls_initalized = true;
931
if_index = (AvahiIfIndex) if_nametoindex(interface);
933
fprintf(stderr, "No such interface: \"%s\"\n", interface);
937
if(connect_to != NULL){
938
/* Connect directly, do not use Zeroconf */
939
/* (Mainly meant for debugging) */
940
char *address = strrchr(connect_to, ':');
942
fprintf(stderr, "No colon in address\n");
943
exitcode = EXIT_FAILURE;
947
uint16_t port = (uint16_t) strtol(address+1, NULL, 10);
949
perror("Bad port number");
950
exitcode = EXIT_FAILURE;
954
address = connect_to;
955
ret = start_mandos_communication(address, port, if_index, &mc);
957
exitcode = EXIT_FAILURE;
959
exitcode = EXIT_SUCCESS;
964
/* If the interface is down, bring it up */
966
sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
969
exitcode = EXIT_FAILURE;
972
strcpy(network.ifr_name, interface); /* Spurious warning */
973
ret = ioctl(sd, SIOCGIFFLAGS, &network);
1381
perror_plus("clock_gettime");
1384
/* Calculating in ms how long time between now and server
1385
who we visted longest time ago. Now - last seen. */
1386
waited_time.tv_sec = (now.tv_sec
1387
- mc->current_server->last_seen.tv_sec);
1388
waited_time.tv_nsec = (now.tv_nsec
1389
- mc->current_server->last_seen.tv_nsec);
1390
/* total time is 10s/10,000ms.
1391
Converting to s from ms by dividing by 1,000,
1392
and ns to ms by dividing by 1,000,000. */
1393
block_time = ((retry_interval
1394
- ((intmax_t)waited_time.tv_sec * 1000))
1395
- ((intmax_t)waited_time.tv_nsec / 1000000));
1398
fprintf_plus(stderr, "Blocking for %" PRIdMAX " ms\n",
1402
if(block_time <= 0){
1403
ret = start_mandos_communication(mc->current_server->ip,
1404
mc->current_server->port,
1405
mc->current_server->if_index,
1406
mc->current_server->af, mc);
1408
avahi_simple_poll_quit(s);
1411
ret = clock_gettime(CLOCK_MONOTONIC,
1412
&mc->current_server->last_seen);
1414
perror_plus("clock_gettime");
1417
mc->current_server = mc->current_server->next;
1418
block_time = 0; /* Call avahi to find new Mandos
1419
servers, but don't block */
1422
ret = avahi_simple_poll_iterate(s, (int)block_time);
1425
if (ret > 0 or errno != EINTR){
1426
return (ret != 1) ? ret : 0;
1432
/* Set effective uid to 0, return errno */
1433
error_t raise_privileges(void){
1434
error_t old_errno = errno;
1435
error_t ret_errno = 0;
1436
if(seteuid(0) == -1){
1438
perror_plus("seteuid");
1444
/* Set effective and real user ID to 0. Return errno. */
1445
error_t raise_privileges_permanently(void){
1446
error_t old_errno = errno;
1447
error_t ret_errno = raise_privileges();
1452
if(setuid(0) == -1){
1454
perror_plus("seteuid");
1460
/* Set effective user ID to unprivileged saved user ID */
1461
error_t lower_privileges(void){
1462
error_t old_errno = errno;
1463
error_t ret_errno = 0;
1464
if(seteuid(uid) == -1){
1466
perror_plus("seteuid");
1472
/* Lower privileges permanently */
1473
error_t lower_privileges_permanently(void){
1474
error_t old_errno = errno;
1475
error_t ret_errno = 0;
1476
if(setuid(uid) == -1){
1478
perror_plus("setuid");
1484
bool run_network_hooks(const char *mode, const char *interface,
1486
struct dirent **direntries;
1487
struct dirent *direntry;
1489
int numhooks = scandir(hookdir, &direntries, runnable_hook,
1492
if(errno == ENOENT){
1494
fprintf_plus(stderr, "Network hook directory \"%s\" not"
1495
" found\n", hookdir);
1498
perror_plus("scandir");
1501
int devnull = open("/dev/null", O_RDONLY);
1502
for(int i = 0; i < numhooks; i++){
1503
direntry = direntries[i];
1504
char *fullname = NULL;
1505
ret = asprintf(&fullname, "%s/%s", hookdir, direntry->d_name);
1507
perror_plus("asprintf");
1511
fprintf_plus(stderr, "Running network hook \"%s\"\n",
1514
pid_t hook_pid = fork();
1517
/* Raise privileges */
1518
raise_privileges_permanently();
1523
perror_plus("setgid");
1525
/* Reset supplementary groups */
1527
ret = setgroups(0, NULL);
1529
perror_plus("setgroups");
1531
dup2(devnull, STDIN_FILENO);
1533
dup2(STDERR_FILENO, STDOUT_FILENO);
1534
ret = setenv("MANDOSNETHOOKDIR", hookdir, 1);
1536
perror_plus("setenv");
1539
ret = setenv("DEVICE", interface, 1);
1541
perror_plus("setenv");
1544
ret = setenv("VERBOSITY", debug ? "1" : "0", 1);
1546
perror_plus("setenv");
1549
ret = setenv("MODE", mode, 1);
1551
perror_plus("setenv");
1555
ret = asprintf(&delaystring, "%f", delay);
1557
perror_plus("asprintf");
1560
ret = setenv("DELAY", delaystring, 1);
1563
perror_plus("setenv");
1567
if(connect_to != NULL){
1568
ret = setenv("CONNECT", connect_to, 1);
1570
perror_plus("setenv");
1574
if(execl(fullname, direntry->d_name, mode, NULL) == -1){
1575
perror_plus("execl");
1576
_exit(EXIT_FAILURE);
1580
if(TEMP_FAILURE_RETRY(waitpid(hook_pid, &status, 0)) == -1){
1581
perror_plus("waitpid");
1585
if(WIFEXITED(status)){
1586
if(WEXITSTATUS(status) != 0){
1587
fprintf_plus(stderr, "Warning: network hook \"%s\" exited"
1588
" with status %d\n", direntry->d_name,
1589
WEXITSTATUS(status));
1593
} else if(WIFSIGNALED(status)){
1594
fprintf_plus(stderr, "Warning: network hook \"%s\" died by"
1595
" signal %d\n", direntry->d_name,
1600
fprintf_plus(stderr, "Warning: network hook \"%s\""
1601
" crashed\n", direntry->d_name);
1608
fprintf_plus(stderr, "Network hook \"%s\" ran successfully\n",
1617
error_t bring_up_interface(const char *const interface,
1620
error_t old_errno = errno;
1621
error_t ret_errno = 0;
1622
int ret, ret_setflags;
1623
struct ifreq network;
1624
unsigned int if_index = if_nametoindex(interface);
1626
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
1636
if(not interface_is_up(interface)){
1637
if(not get_flags(interface, &network) and debug){
1639
fprintf_plus(stderr, "Failed to get flags for interface "
1640
"\"%s\"\n", interface);
1643
network.ifr_flags |= IFF_UP;
1645
sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1648
perror_plus("socket");
975
perror("ioctl SIOCGIFFLAGS");
976
exitcode = EXIT_FAILURE;
979
if((network.ifr_flags & IFF_UP) == 0){
980
network.ifr_flags |= IFF_UP;
981
ret = ioctl(sd, SIOCSIFFLAGS, &network);
983
perror("ioctl SIOCSIFFLAGS");
984
exitcode = EXIT_FAILURE;
1660
fprintf_plus(stderr, "Bringing up interface \"%s\"\n",
1664
/* Raise priviliges */
1668
/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO
1669
messages about the network interface to mess up the prompt */
1670
int ret_linux = klogctl(8, NULL, 5);
1671
bool restore_loglevel = true;
1672
if(ret_linux == -1){
1673
restore_loglevel = false;
1674
perror_plus("klogctl");
1676
#endif /* __linux__ */
1677
ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
1680
if(restore_loglevel){
1681
ret_linux = klogctl(7, NULL, 0);
1682
if(ret_linux == -1){
1683
perror_plus("klogctl");
1686
#endif /* __linux__ */
1688
/* Lower privileges */
1691
/* Close the socket */
1692
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1694
perror_plus("close");
1697
if(ret_setflags == -1){
1699
perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");
1704
fprintf_plus(stderr, "Interface \"%s\" is already up; good\n",
1708
/* Sleep checking until interface is running.
1709
Check every 0.25s, up to total time of delay */
1710
for(int i=0; i < delay * 4; i++){
1711
if(interface_is_running(interface)){
1714
struct timespec sleeptime = { .tv_nsec = 250000000 };
1715
ret = nanosleep(&sleeptime, NULL);
1716
if(ret == -1 and errno != EINTR){
1717
perror_plus("nanosleep");
1725
error_t take_down_interface(const char *const interface){
1727
error_t old_errno = errno;
1728
error_t ret_errno = 0;
1729
int ret, ret_setflags;
1730
struct ifreq network;
1731
unsigned int if_index = if_nametoindex(interface);
1733
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
1737
if(interface_is_up(interface)){
1738
if(not get_flags(interface, &network) and debug){
1740
fprintf_plus(stderr, "Failed to get flags for interface "
1741
"\"%s\"\n", interface);
1744
network.ifr_flags &= ~(short)IFF_UP; /* clear flag */
1746
sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1749
perror_plus("socket");
1755
fprintf_plus(stderr, "Taking down interface \"%s\"\n",
1759
/* Raise priviliges */
1762
ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
1765
/* Lower privileges */
1768
/* Close the socket */
1769
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1771
perror_plus("close");
1774
if(ret_setflags == -1){
1776
perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");
1781
fprintf_plus(stderr, "Interface \"%s\" is already down; odd\n",
1789
int main(int argc, char *argv[]){
1790
mandos_context mc = { .server = NULL, .dh_bits = 1024,
1791
.priority = "SECURE256:!CTYPE-X.509:"
1792
"+CTYPE-OPENPGP", .current_server = NULL,
1793
.interfaces = NULL, .interfaces_size = 0 };
1794
AvahiSServiceBrowser *sb = NULL;
1799
int exitcode = EXIT_SUCCESS;
1800
char *interfaces_to_take_down = NULL;
1801
size_t interfaces_to_take_down_size = 0;
1802
char tempdir[] = "/tmp/mandosXXXXXX";
1803
bool tempdir_created = false;
1804
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
1805
const char *seckey = PATHDIR "/" SECKEY;
1806
const char *pubkey = PATHDIR "/" PUBKEY;
1807
char *interfaces_hooks = NULL;
1808
size_t interfaces_hooks_size = 0;
1810
bool gnutls_initialized = false;
1811
bool gpgme_initialized = false;
1813
double retry_interval = 10; /* 10s between trying a server and
1814
retrying the same server again */
1816
struct sigaction old_sigterm_action = { .sa_handler = SIG_DFL };
1817
struct sigaction sigterm_action = { .sa_handler = handle_sigterm };
1822
/* Lower any group privileges we might have, just to be safe */
1826
perror_plus("setgid");
1829
/* Lower user privileges (temporarily) */
1833
perror_plus("seteuid");
1841
struct argp_option options[] = {
1842
{ .name = "debug", .key = 128,
1843
.doc = "Debug mode", .group = 3 },
1844
{ .name = "connect", .key = 'c',
1845
.arg = "ADDRESS:PORT",
1846
.doc = "Connect directly to a specific Mandos server",
1848
{ .name = "interface", .key = 'i',
1850
.doc = "Network interface that will be used to search for"
1853
{ .name = "seckey", .key = 's',
1855
.doc = "OpenPGP secret key file base name",
1857
{ .name = "pubkey", .key = 'p',
1859
.doc = "OpenPGP public key file base name",
1861
{ .name = "dh-bits", .key = 129,
1863
.doc = "Bit length of the prime number used in the"
1864
" Diffie-Hellman key exchange",
1866
{ .name = "priority", .key = 130,
1868
.doc = "GnuTLS priority string for the TLS handshake",
1870
{ .name = "delay", .key = 131,
1872
.doc = "Maximum delay to wait for interface startup",
1874
{ .name = "retry", .key = 132,
1876
.doc = "Retry interval used when denied by the Mandos server",
1878
{ .name = "network-hook-dir", .key = 133,
1880
.doc = "Directory where network hooks are located",
1883
* These reproduce what we would get without ARGP_NO_HELP
1885
{ .name = "help", .key = '?',
1886
.doc = "Give this help list", .group = -1 },
1887
{ .name = "usage", .key = -3,
1888
.doc = "Give a short usage message", .group = -1 },
1889
{ .name = "version", .key = 'V',
1890
.doc = "Print program version", .group = -1 },
1894
error_t parse_opt(int key, char *arg,
1895
struct argp_state *state){
1898
case 128: /* --debug */
1901
case 'c': /* --connect */
1904
case 'i': /* --interface */
1905
ret_errno = argz_add_sep(&mc.interfaces, &mc.interfaces_size,
1908
argp_error(state, "%s", strerror(ret_errno));
1911
case 's': /* --seckey */
1914
case 'p': /* --pubkey */
1917
case 129: /* --dh-bits */
1919
tmpmax = strtoimax(arg, &tmp, 10);
1920
if(errno != 0 or tmp == arg or *tmp != '\0'
1921
or tmpmax != (typeof(mc.dh_bits))tmpmax){
1922
argp_error(state, "Bad number of DH bits");
1924
mc.dh_bits = (typeof(mc.dh_bits))tmpmax;
1926
case 130: /* --priority */
1929
case 131: /* --delay */
1931
delay = strtof(arg, &tmp);
1932
if(errno != 0 or tmp == arg or *tmp != '\0'){
1933
argp_error(state, "Bad delay");
1935
case 132: /* --retry */
1937
retry_interval = strtod(arg, &tmp);
1938
if(errno != 0 or tmp == arg or *tmp != '\0'
1939
or (retry_interval * 1000) > INT_MAX
1940
or retry_interval < 0){
1941
argp_error(state, "Bad retry interval");
1944
case 133: /* --network-hook-dir */
1948
* These reproduce what we would get without ARGP_NO_HELP
1950
case '?': /* --help */
1951
argp_state_help(state, state->out_stream,
1952
(ARGP_HELP_STD_HELP | ARGP_HELP_EXIT_ERR)
1953
& ~(unsigned int)ARGP_HELP_EXIT_OK);
1954
case -3: /* --usage */
1955
argp_state_help(state, state->out_stream,
1956
ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);
1957
case 'V': /* --version */
1958
fprintf_plus(state->out_stream, "%s\n", argp_program_version);
1959
exit(argp_err_exit_status);
1962
return ARGP_ERR_UNKNOWN;
1967
struct argp argp = { .options = options, .parser = parse_opt,
1969
.doc = "Mandos client -- Get and decrypt"
1970
" passwords from a Mandos server" };
1971
ret = argp_parse(&argp, argc, argv,
1972
ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);
1979
perror_plus("argp_parse");
1980
exitcode = EX_OSERR;
1983
exitcode = EX_USAGE;
1989
/* Work around Debian bug #633582:
1990
<http://bugs.debian.org/633582> */
1992
/* Re-raise priviliges */
1993
if(raise_privileges() == 0){
1996
if(strcmp(seckey, PATHDIR "/" SECKEY) == 0){
1997
int seckey_fd = open(seckey, O_RDONLY);
1998
if(seckey_fd == -1){
1999
perror_plus("open");
2001
ret = (int)TEMP_FAILURE_RETRY(fstat(seckey_fd, &st));
2003
perror_plus("fstat");
2005
if(S_ISREG(st.st_mode)
2006
and st.st_uid == 0 and st.st_gid == 0){
2007
ret = fchown(seckey_fd, uid, gid);
2009
perror_plus("fchown");
2013
TEMP_FAILURE_RETRY(close(seckey_fd));
2017
if(strcmp(pubkey, PATHDIR "/" PUBKEY) == 0){
2018
int pubkey_fd = open(pubkey, O_RDONLY);
2019
if(pubkey_fd == -1){
2020
perror_plus("open");
2022
ret = (int)TEMP_FAILURE_RETRY(fstat(pubkey_fd, &st));
2024
perror_plus("fstat");
2026
if(S_ISREG(st.st_mode)
2027
and st.st_uid == 0 and st.st_gid == 0){
2028
ret = fchown(pubkey_fd, uid, gid);
2030
perror_plus("fchown");
2034
TEMP_FAILURE_RETRY(close(pubkey_fd));
2038
/* Lower privileges */
2043
/* Remove invalid interface names (except "none") */
2045
char *interface = NULL;
2046
while((interface = argz_next(mc.interfaces, mc.interfaces_size,
2048
if(strcmp(interface, "none") != 0
2049
and if_nametoindex(interface) == 0){
2050
if(interface[0] != '\0'){
2051
fprintf_plus(stderr, "Not using nonexisting interface"
2052
" \"%s\"\n", interface);
2054
argz_delete(&mc.interfaces, &mc.interfaces_size, interface);
2060
/* Run network hooks */
2062
if(mc.interfaces != NULL){
2063
interfaces_hooks = malloc(mc.interfaces_size);
2064
if(interfaces_hooks == NULL){
2065
perror_plus("malloc");
2068
memcpy(interfaces_hooks, mc.interfaces, mc.interfaces_size);
2069
interfaces_hooks_size = mc.interfaces_size;
2070
argz_stringify(interfaces_hooks, interfaces_hooks_size,
2073
if(not run_network_hooks("start", interfaces_hooks != NULL ?
2074
interfaces_hooks : "", delay)){
2080
avahi_set_log_function(empty_log);
2083
/* Initialize Avahi early so avahi_simple_poll_quit() can be called
2084
from the signal handler */
2085
/* Initialize the pseudo-RNG for Avahi */
2086
srand((unsigned int) time(NULL));
2087
simple_poll = avahi_simple_poll_new();
2088
if(simple_poll == NULL){
2089
fprintf_plus(stderr,
2090
"Avahi: Failed to create simple poll object.\n");
2091
exitcode = EX_UNAVAILABLE;
2095
sigemptyset(&sigterm_action.sa_mask);
2096
ret = sigaddset(&sigterm_action.sa_mask, SIGINT);
2098
perror_plus("sigaddset");
2099
exitcode = EX_OSERR;
2102
ret = sigaddset(&sigterm_action.sa_mask, SIGHUP);
2104
perror_plus("sigaddset");
2105
exitcode = EX_OSERR;
2108
ret = sigaddset(&sigterm_action.sa_mask, SIGTERM);
2110
perror_plus("sigaddset");
2111
exitcode = EX_OSERR;
2114
/* Need to check if the handler is SIG_IGN before handling:
2115
| [[info:libc:Initial Signal Actions]] |
2116
| [[info:libc:Basic Signal Handling]] |
2118
ret = sigaction(SIGINT, NULL, &old_sigterm_action);
2120
perror_plus("sigaction");
2123
if(old_sigterm_action.sa_handler != SIG_IGN){
2124
ret = sigaction(SIGINT, &sigterm_action, NULL);
2126
perror_plus("sigaction");
2127
exitcode = EX_OSERR;
2131
ret = sigaction(SIGHUP, NULL, &old_sigterm_action);
2133
perror_plus("sigaction");
2136
if(old_sigterm_action.sa_handler != SIG_IGN){
2137
ret = sigaction(SIGHUP, &sigterm_action, NULL);
2139
perror_plus("sigaction");
2140
exitcode = EX_OSERR;
2144
ret = sigaction(SIGTERM, NULL, &old_sigterm_action);
2146
perror_plus("sigaction");
2149
if(old_sigterm_action.sa_handler != SIG_IGN){
2150
ret = sigaction(SIGTERM, &sigterm_action, NULL);
2152
perror_plus("sigaction");
2153
exitcode = EX_OSERR;
2158
/* If no interfaces were specified, make a list */
2159
if(mc.interfaces == NULL){
2160
struct dirent **direntries;
2161
/* Look for any good interfaces */
2162
ret = scandir(sys_class_net, &direntries, good_interface,
2165
/* Add all found interfaces to interfaces list */
2166
for(int i = 0; i < ret; ++i){
2167
ret_errno = argz_add(&mc.interfaces, &mc.interfaces_size,
2168
direntries[i]->d_name);
2170
perror_plus("argz_add");
2174
fprintf_plus(stderr, "Will use interface \"%s\"\n",
2175
direntries[i]->d_name);
2181
fprintf_plus(stderr, "Could not find a network interface\n");
2182
exitcode = EXIT_FAILURE;
2187
/* Bring up interfaces which are down, and remove any "none"s */
2189
char *interface = NULL;
2190
while((interface = argz_next(mc.interfaces, mc.interfaces_size,
2192
/* If interface name is "none", stop bringing up interfaces.
2193
Also remove all instances of "none" from the list */
2194
if(strcmp(interface, "none") == 0){
2195
argz_delete(&mc.interfaces, &mc.interfaces_size,
2198
while((interface = argz_next(mc.interfaces,
2199
mc.interfaces_size, interface))){
2200
if(strcmp(interface, "none") == 0){
2201
argz_delete(&mc.interfaces, &mc.interfaces_size,
2208
bool interface_was_up = interface_is_up(interface);
2209
ret = bring_up_interface(interface, delay);
2210
if(not interface_was_up){
2213
perror_plus("Failed to bring up interface");
2215
ret_errno = argz_add(&interfaces_to_take_down,
2216
&interfaces_to_take_down_size,
2221
if(debug and (interfaces_to_take_down == NULL)){
2222
fprintf_plus(stderr, "No interfaces were brought up\n");
2226
/* If we only got one interface, explicitly use only that one */
2227
if(argz_count(mc.interfaces, mc.interfaces_size) == 1){
2229
fprintf_plus(stderr, "Using only interface \"%s\"\n",
2232
if_index = (AvahiIfIndex)if_nametoindex(mc.interfaces);
2239
ret = init_gnutls_global(pubkey, seckey, &mc);
2241
fprintf_plus(stderr, "init_gnutls_global failed\n");
2242
exitcode = EX_UNAVAILABLE;
2245
gnutls_initialized = true;
2252
if(mkdtemp(tempdir) == NULL){
2253
perror_plus("mkdtemp");
2256
tempdir_created = true;
2262
if(not init_gpgme(pubkey, seckey, tempdir, &mc)){
2263
fprintf_plus(stderr, "init_gpgme failed\n");
2264
exitcode = EX_UNAVAILABLE;
2267
gpgme_initialized = true;
2274
if(connect_to != NULL){
2275
/* Connect directly, do not use Zeroconf */
2276
/* (Mainly meant for debugging) */
2277
char *address = strrchr(connect_to, ':');
2279
if(address == NULL){
2280
fprintf_plus(stderr, "No colon in address\n");
2281
exitcode = EX_USAGE;
2291
tmpmax = strtoimax(address+1, &tmp, 10);
2292
if(errno != 0 or tmp == address+1 or *tmp != '\0'
2293
or tmpmax != (in_port_t)tmpmax){
2294
fprintf_plus(stderr, "Bad port number\n");
2295
exitcode = EX_USAGE;
2303
port = (in_port_t)tmpmax;
2305
/* Colon in address indicates IPv6 */
2307
if(strchr(connect_to, ':') != NULL){
2309
/* Accept [] around IPv6 address - see RFC 5952 */
2310
if(connect_to[0] == '[' and address[-1] == ']')
2318
address = connect_to;
2324
while(not quit_now){
2325
ret = start_mandos_communication(address, port, if_index, af,
2327
if(quit_now or ret == 0){
2331
fprintf_plus(stderr, "Retrying in %d seconds\n",
2332
(int)retry_interval);
2334
sleep((unsigned int)retry_interval);
2338
exitcode = EXIT_SUCCESS;
2349
AvahiServerConfig config;
2350
/* Do not publish any local Zeroconf records */
2351
avahi_server_config_init(&config);
2352
config.publish_hinfo = 0;
2353
config.publish_addresses = 0;
2354
config.publish_workstation = 0;
2355
config.publish_domain = 0;
2357
/* Allocate a new server */
2358
mc.server = avahi_server_new(avahi_simple_poll_get(simple_poll),
2359
&config, NULL, NULL, &ret_errno);
2361
/* Free the Avahi configuration data */
2362
avahi_server_config_free(&config);
2365
/* Check if creating the Avahi server object succeeded */
2366
if(mc.server == NULL){
2367
fprintf_plus(stderr, "Failed to create Avahi server: %s\n",
2368
avahi_strerror(ret_errno));
2369
exitcode = EX_UNAVAILABLE;
2377
/* Create the Avahi service browser */
2378
sb = avahi_s_service_browser_new(mc.server, if_index,
2379
AVAHI_PROTO_UNSPEC, "_mandos._tcp",
2380
NULL, 0, browse_callback,
2383
fprintf_plus(stderr, "Failed to create service browser: %s\n",
2384
avahi_strerror(avahi_server_errno(mc.server)));
2385
exitcode = EX_UNAVAILABLE;
2393
/* Run the main loop */
2396
fprintf_plus(stderr, "Starting Avahi loop search\n");
2399
ret = avahi_loop_with_timeout(simple_poll,
2400
(int)(retry_interval * 1000), &mc);
2402
fprintf_plus(stderr, "avahi_loop_with_timeout exited %s\n",
2403
(ret == 0) ? "successfully" : "with error");
992
avahi_set_log_function(empty_log);
995
/* Initialize the pseudo-RNG for Avahi */
996
srand((unsigned int) time(NULL));
998
/* Allocate main Avahi loop object */
999
mc.simple_poll = avahi_simple_poll_new();
1000
if (mc.simple_poll == NULL) {
1001
fprintf(stderr, "Avahi: Failed to create simple poll"
1003
exitcode = EXIT_FAILURE;
1008
AvahiServerConfig config;
1009
/* Do not publish any local Zeroconf records */
1010
avahi_server_config_init(&config);
1011
config.publish_hinfo = 0;
1012
config.publish_addresses = 0;
1013
config.publish_workstation = 0;
1014
config.publish_domain = 0;
1016
/* Allocate a new server */
1017
mc.server = avahi_server_new(avahi_simple_poll_get
1018
(mc.simple_poll), &config, NULL,
1021
/* Free the Avahi configuration data */
1022
avahi_server_config_free(&config);
1025
/* Check if creating the Avahi server object succeeded */
1026
if (mc.server == NULL) {
1027
fprintf(stderr, "Failed to create Avahi server: %s\n",
1028
avahi_strerror(error));
1029
exitcode = EXIT_FAILURE;
1033
/* Create the Avahi service browser */
1034
sb = avahi_s_service_browser_new(mc.server, if_index,
1036
"_mandos._tcp", NULL, 0,
1037
browse_callback, &mc);
1039
fprintf(stderr, "Failed to create service browser: %s\n",
1040
avahi_strerror(avahi_server_errno(mc.server)));
1041
exitcode = EXIT_FAILURE;
1045
/* Run the main loop */
1048
fprintf(stderr, "Starting Avahi loop search\n");
1051
avahi_simple_poll_loop(mc.simple_poll);
2409
fprintf_plus(stderr, "%s exiting\n", argv[0]);
2412
/* Cleanup things */
2413
free(mc.interfaces);
2416
avahi_s_service_browser_free(sb);
2418
if(mc.server != NULL)
2419
avahi_server_free(mc.server);
2421
if(simple_poll != NULL)
2422
avahi_simple_poll_free(simple_poll);
2424
if(gnutls_initialized){
2425
gnutls_certificate_free_credentials(mc.cred);
2426
gnutls_global_deinit();
2427
gnutls_dh_params_deinit(mc.dh_params);
2430
if(gpgme_initialized){
2431
gpgme_release(mc.ctx);
2434
/* Cleans up the circular linked list of Mandos servers the client
2436
if(mc.current_server != NULL){
2437
mc.current_server->prev->next = NULL;
2438
while(mc.current_server != NULL){
2439
server *next = mc.current_server->next;
2440
free(mc.current_server);
2441
mc.current_server = next;
2445
/* Re-raise priviliges */
2449
/* Run network hooks */
2450
run_network_hooks("stop", interfaces_hooks != NULL ?
2451
interfaces_hooks : "", delay);
2453
/* Take down the network interfaces which were brought up */
2455
char *interface = NULL;
2456
while((interface=argz_next(interfaces_to_take_down,
2457
interfaces_to_take_down_size,
2459
ret_errno = take_down_interface(interface);
2462
perror_plus("Failed to take down interface");
2465
if(debug and (interfaces_to_take_down == NULL)){
2466
fprintf_plus(stderr, "No interfaces needed to be taken"
2471
lower_privileges_permanently();
2474
free(interfaces_to_take_down);
2475
free(interfaces_hooks);
2477
/* Removes the GPGME temp directory and all files inside */
2478
if(tempdir_created){
2479
struct dirent **direntries = NULL;
2480
struct dirent *direntry = NULL;
2481
int numentries = scandir(tempdir, &direntries, notdotentries,
2483
if (numentries > 0){
2484
for(int i = 0; i < numentries; i++){
2485
direntry = direntries[i];
2486
char *fullname = NULL;
2487
ret = asprintf(&fullname, "%s/%s", tempdir,
2490
perror_plus("asprintf");
2493
ret = remove(fullname);
2495
fprintf_plus(stderr, "remove(\"%s\"): %s\n", fullname,
2502
/* need to clean even if 0 because man page doesn't specify */
2504
if (numentries == -1){
2505
perror_plus("scandir");
2507
ret = rmdir(tempdir);
2508
if(ret == -1 and errno != ENOENT){
2509
perror_plus("rmdir");
2514
sigemptyset(&old_sigterm_action.sa_mask);
2515
old_sigterm_action.sa_handler = SIG_DFL;
2516
ret = (int)TEMP_FAILURE_RETRY(sigaction(signal_received,
2517
&old_sigterm_action,
2520
perror_plus("sigaction");
2523
ret = raise(signal_received);
2524
} while(ret != 0 and errno == EINTR);
2526
perror_plus("raise");
2529
TEMP_FAILURE_RETRY(pause());
1056
fprintf(stderr, "%s exiting\n", argv[0]);
1059
/* Cleanup things */
1061
avahi_s_service_browser_free(sb);
1063
if (mc.server != NULL)
1064
avahi_server_free(mc.server);
1066
if (mc.simple_poll != NULL)
1067
avahi_simple_poll_free(mc.simple_poll);
1071
if (gnutls_initalized){
1072
gnutls_certificate_free_credentials (mc.cred);
1073
gnutls_global_deinit ();