9
9
* "browse_callback", and parts of "main".
11
11
* Everything else is
12
* Copyright © 2008-2020 Teddy Hogeborn
13
* Copyright © 2008-2020 Björn Påhlsson
15
* This file is part of Mandos.
17
* Mandos is free software: you can redistribute it and/or modify it
18
* under the terms of the GNU General Public License as published by
19
* the Free Software Foundation, either version 3 of the License, or
20
* (at your option) any later version.
22
* Mandos is distributed in the hope that it will be useful, but
12
* Copyright © 2008-2015 Teddy Hogeborn
13
* Copyright © 2008-2015 Björn Påhlsson
15
* This program is free software: you can redistribute it and/or
16
* modify it under the terms of the GNU General Public License as
17
* published by the Free Software Foundation, either version 3 of the
18
* License, or (at your option) any later version.
20
* This program is distributed in the hope that it will be useful, but
23
21
* WITHOUT ANY WARRANTY; without even the implied warranty of
24
22
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
25
23
* General Public License for more details.
27
25
* You should have received a copy of the GNU General Public License
28
* along with Mandos. If not, see <http://www.gnu.org/licenses/>.
26
* along with this program. If not, see
27
* <http://www.gnu.org/licenses/>.
30
29
* Contact the authors at <mandos@recompile.se>.
59
57
#include <sys/socket.h> /* socket(), struct sockaddr_in6,
60
58
inet_pton(), connect(),
62
#include <fcntl.h> /* open(), unlinkat(), AT_REMOVEDIR */
60
#include <fcntl.h> /* open(), unlinkat() */
63
61
#include <dirent.h> /* opendir(), struct dirent, readdir()
65
63
#include <inttypes.h> /* PRIu16, PRIdMAX, intmax_t,
67
#include <errno.h> /* perror(), errno, EINTR, EINVAL,
68
EAI_SYSTEM, ENETUNREACH,
69
EHOSTUNREACH, ECONNREFUSED, EPROTO,
70
EIO, ENOENT, ENXIO, ENOMEM, EISDIR,
65
#include <errno.h> /* perror(), errno,
72
66
program_invocation_short_name */
73
67
#include <time.h> /* nanosleep(), time(), sleep() */
74
68
#include <net/if.h> /* ioctl, ifreq, SIOCGIFFLAGS, IFF_UP,
360
/* Workaround for systems without a real-time clock; see also
361
Debian bug #894495: <https://bugs.debian.org/894495> */
364
time_t currtime = time(NULL);
365
if(currtime != (time_t)-1){
367
if(gmtime_r(&currtime, &tm) == NULL) {
368
perror_plus("gmtime_r");
371
if(tm.tm_year != 70 or tm.tm_mon != 0){
375
fprintf_plus(stderr, "System clock is January 1970");
379
fprintf_plus(stderr, "System clock is invalid");
384
ret = fstat(fd, &keystat);
386
perror_plus("fstat");
389
ret = raise_privileges();
392
perror_plus("Failed to raise privileges");
397
"Setting system clock to key file mtime");
399
if(clock_settime(CLOCK_REALTIME, &keystat.st_mtim) != 0){
400
perror_plus("clock_settime");
402
ret = lower_privileges();
405
perror_plus("Failed to lower privileges");
409
294
rc = gpgme_data_new_from_fd(&pgp_data, fd);
410
295
if(rc != GPG_ERR_NO_ERROR){
411
296
fprintf_plus(stderr, "bad gpgme_data_new_from_fd: %s: %s\n",
419
304
gpgme_strsource(rc), gpgme_strerror(rc));
423
gpgme_import_result_t import_result
424
= gpgme_op_import_result(mc->ctx);
425
if((import_result->imported < 1
426
or import_result->not_imported > 0)
427
and import_result->unchanged == 0){
428
fprintf_plus(stderr, "bad gpgme_op_import_results:\n");
430
"The total number of considered keys: %d\n",
431
import_result->considered);
433
"The number of keys without user ID: %d\n",
434
import_result->no_user_id);
436
"The total number of imported keys: %d\n",
437
import_result->imported);
438
fprintf_plus(stderr, "The number of imported RSA keys: %d\n",
439
import_result->imported_rsa);
440
fprintf_plus(stderr, "The number of unchanged keys: %d\n",
441
import_result->unchanged);
442
fprintf_plus(stderr, "The number of new user IDs: %d\n",
443
import_result->new_user_ids);
444
fprintf_plus(stderr, "The number of new sub keys: %d\n",
445
import_result->new_sub_keys);
446
fprintf_plus(stderr, "The number of new signatures: %d\n",
447
import_result->new_signatures);
448
fprintf_plus(stderr, "The number of new revocations: %d\n",
449
import_result->new_revocations);
451
"The total number of secret keys read: %d\n",
452
import_result->secret_read);
454
"The number of imported secret keys: %d\n",
455
import_result->secret_imported);
457
"The number of unchanged secret keys: %d\n",
458
import_result->secret_unchanged);
459
fprintf_plus(stderr, "The number of keys not imported: %d\n",
460
import_result->not_imported);
461
for(gpgme_import_status_t import_status
462
= import_result->imports;
463
import_status != NULL;
464
import_status = import_status->next){
465
fprintf_plus(stderr, "Import status for key: %s\n",
467
if(import_status->result != GPG_ERR_NO_ERROR){
468
fprintf_plus(stderr, "Import result: %s: %s\n",
469
gpgme_strsource(import_status->result),
470
gpgme_strerror(import_status->result));
472
fprintf_plus(stderr, "Key status:\n");
474
import_status->status & GPGME_IMPORT_NEW
475
? "The key was new.\n"
476
: "The key was not new.\n");
478
import_status->status & GPGME_IMPORT_UID
479
? "The key contained new user IDs.\n"
480
: "The key did not contain new user IDs.\n");
482
import_status->status & GPGME_IMPORT_SIG
483
? "The key contained new signatures.\n"
484
: "The key did not contain new signatures.\n");
486
import_status->status & GPGME_IMPORT_SUBKEY
487
? "The key contained new sub keys.\n"
488
: "The key did not contain new sub keys.\n");
490
import_status->status & GPGME_IMPORT_SECRET
491
? "The key contained a secret key.\n"
492
: "The key did not contain a secret key.\n");
308
ret = (int)TEMP_FAILURE_RETRY(close(fd));
500
310
perror_plus("close");
602
414
if(result == NULL){
603
415
fprintf_plus(stderr, "gpgme_op_decrypt_result failed\n");
605
if(result->unsupported_algorithm != NULL) {
606
fprintf_plus(stderr, "Unsupported algorithm: %s\n",
607
result->unsupported_algorithm);
609
fprintf_plus(stderr, "Wrong key usage: %s\n",
610
result->wrong_key_usage ? "Yes" : "No");
417
fprintf_plus(stderr, "Unsupported algorithm: %s\n",
418
result->unsupported_algorithm);
419
fprintf_plus(stderr, "Wrong key usage: %u\n",
420
result->wrong_key_usage);
611
421
if(result->file_name != NULL){
612
422
fprintf_plus(stderr, "File name: %s\n", result->file_name);
615
for(gpgme_recipient_t r = result->recipients; r != NULL;
424
gpgme_recipient_t recipient;
425
recipient = result->recipients;
426
while(recipient != NULL){
617
427
fprintf_plus(stderr, "Public key algorithm: %s\n",
618
gpgme_pubkey_algo_name(r->pubkey_algo));
619
fprintf_plus(stderr, "Key ID: %s\n", r->keyid);
428
gpgme_pubkey_algo_name
429
(recipient->pubkey_algo));
430
fprintf_plus(stderr, "Key ID: %s\n", recipient->keyid);
620
431
fprintf_plus(stderr, "Secret key available: %s\n",
621
r->status == GPG_ERR_NO_SECKEY ? "No" : "Yes");
432
recipient->status == GPG_ERR_NO_SECKEY
434
recipient = recipient->next;
724
538
if(ret != GNUTLS_E_SUCCESS){
725
539
fprintf_plus(stderr, "GnuTLS memory error: %s\n",
726
540
safer_gnutls_strerror(ret));
541
gnutls_global_deinit();
731
fprintf_plus(stderr, "Attempting to use public key %s and"
732
" private key %s as GnuTLS credentials\n",
546
fprintf_plus(stderr, "Attempting to use OpenPGP public key %s and"
547
" secret key %s as GnuTLS credentials\n",
737
#if GNUTLS_VERSION_NUMBER >= 0x030606
738
ret = gnutls_certificate_set_rawpk_key_file
739
(mc->cred, pubkeyfilename, seckeyfilename,
740
GNUTLS_X509_FMT_PEM, /* format */
743
GNUTLS_KEY_DIGITAL_SIGNATURE | GNUTLS_KEY_KEY_ENCIPHERMENT,
745
0, /* names_length */
747
GNUTLS_PKCS_PLAIN | GNUTLS_PKCS_NULL_PASSWORD,
748
0); /* pkcs11_flags */
749
#elif GNUTLS_VERSION_NUMBER < 0x030600
750
552
ret = gnutls_certificate_set_openpgp_key_file
751
553
(mc->cred, pubkeyfilename, seckeyfilename,
752
554
GNUTLS_OPENPGP_FMT_BASE64);
754
#error "Needs GnuTLS 3.6.6 or later, or before 3.6.0"
756
555
if(ret != GNUTLS_E_SUCCESS){
757
556
fprintf_plus(stderr,
758
"Error[%d] while reading the key pair ('%s',"
557
"Error[%d] while reading the OpenPGP key pair ('%s',"
759
558
" '%s')\n", ret, pubkeyfilename, seckeyfilename);
760
559
fprintf_plus(stderr, "The GnuTLS error is: %s\n",
761
560
safer_gnutls_strerror(ret));
770
569
safer_gnutls_strerror(ret));
773
/* If a Diffie-Hellman parameters file was given, try to use it */
774
if(dhparamsfilename != NULL){
775
gnutls_datum_t params = { .data = NULL, .size = 0 };
777
int dhpfile = open(dhparamsfilename, O_RDONLY);
780
dhparamsfilename = NULL;
783
size_t params_capacity = 0;
785
params_capacity = incbuffer((char **)¶ms.data,
787
(size_t)params_capacity);
788
if(params_capacity == 0){
789
perror_plus("incbuffer");
792
dhparamsfilename = NULL;
795
ssize_t bytes_read = read(dhpfile,
796
params.data + params.size,
802
/* check bytes_read for failure */
807
dhparamsfilename = NULL;
810
params.size += (unsigned int)bytes_read;
812
ret = close(dhpfile);
814
perror_plus("close");
816
if(params.data == NULL){
817
dhparamsfilename = NULL;
819
if(dhparamsfilename == NULL){
822
ret = gnutls_dh_params_import_pkcs3(mc->dh_params, ¶ms,
823
GNUTLS_X509_FMT_PEM);
824
if(ret != GNUTLS_E_SUCCESS){
825
fprintf_plus(stderr, "Failed to parse DH parameters in file"
826
" \"%s\": %s\n", dhparamsfilename,
827
safer_gnutls_strerror(ret));
828
dhparamsfilename = NULL;
833
if(dhparamsfilename == NULL){
834
if(mc->dh_bits == 0){
835
#if GNUTLS_VERSION_NUMBER < 0x030600
836
/* Find out the optimal number of DH bits */
837
/* Try to read the private key file */
838
gnutls_datum_t buffer = { .data = NULL, .size = 0 };
840
int secfile = open(seckeyfilename, O_RDONLY);
845
size_t buffer_capacity = 0;
847
buffer_capacity = incbuffer((char **)&buffer.data,
849
(size_t)buffer_capacity);
850
if(buffer_capacity == 0){
851
perror_plus("incbuffer");
856
ssize_t bytes_read = read(secfile,
857
buffer.data + buffer.size,
863
/* check bytes_read for failure */
870
buffer.size += (unsigned int)bytes_read;
874
/* If successful, use buffer to parse private key */
875
gnutls_sec_param_t sec_param = GNUTLS_SEC_PARAM_ULTRA;
876
if(buffer.data != NULL){
878
gnutls_openpgp_privkey_t privkey = NULL;
879
ret = gnutls_openpgp_privkey_init(&privkey);
880
if(ret != GNUTLS_E_SUCCESS){
881
fprintf_plus(stderr, "Error initializing OpenPGP key"
883
safer_gnutls_strerror(ret));
887
ret = gnutls_openpgp_privkey_import
888
(privkey, &buffer, GNUTLS_OPENPGP_FMT_BASE64, "", 0);
889
if(ret != GNUTLS_E_SUCCESS){
890
fprintf_plus(stderr, "Error importing OpenPGP key : %s",
891
safer_gnutls_strerror(ret));
897
/* Use private key to suggest an appropriate
899
sec_param = gnutls_openpgp_privkey_sec_param(privkey);
900
gnutls_openpgp_privkey_deinit(privkey);
902
fprintf_plus(stderr, "This OpenPGP key implies using"
903
" a GnuTLS security parameter \"%s\".\n",
904
safe_string(gnutls_sec_param_get_name
910
if(sec_param == GNUTLS_SEC_PARAM_UNKNOWN){
911
/* Err on the side of caution */
912
sec_param = GNUTLS_SEC_PARAM_ULTRA;
914
fprintf_plus(stderr, "Falling back to security parameter"
916
safe_string(gnutls_sec_param_get_name
921
unsigned int uret = gnutls_sec_param_to_pk_bits(GNUTLS_PK_DH, sec_param);
925
fprintf_plus(stderr, "A \"%s\" GnuTLS security parameter"
926
" implies %u DH bits; using that.\n",
927
safe_string(gnutls_sec_param_get_name
932
fprintf_plus(stderr, "Failed to get implied number of DH"
933
" bits for security parameter \"%s\"): %s\n",
934
safe_string(gnutls_sec_param_get_name
936
safer_gnutls_strerror(ret));
940
} else { /* dh_bits != 0 */
942
fprintf_plus(stderr, "DH bits explicitly set to %u\n",
945
ret = gnutls_dh_params_generate2(mc->dh_params, mc->dh_bits);
946
if(ret != GNUTLS_E_SUCCESS){
947
fprintf_plus(stderr, "Error in GnuTLS prime generation (%u"
948
" bits): %s\n", mc->dh_bits,
949
safer_gnutls_strerror(ret));
952
gnutls_certificate_set_dh_params(mc->cred, mc->dh_params);
572
ret = gnutls_dh_params_generate2(mc->dh_params, mc->dh_bits);
573
if(ret != GNUTLS_E_SUCCESS){
574
fprintf_plus(stderr, "Error in GnuTLS prime generation: %s\n",
575
safer_gnutls_strerror(ret));
579
gnutls_certificate_set_dh_params(mc->cred, mc->dh_params);
960
585
gnutls_certificate_free_credentials(mc->cred);
586
gnutls_global_deinit();
961
587
gnutls_dh_params_deinit(mc->dh_params);
1029
650
static void empty_log(__attribute__((unused)) AvahiLogLevel level,
1030
651
__attribute__((unused)) const char *txt){}
1032
/* Helper function to add_local_route() and delete_local_route() */
653
/* Set effective uid to 0, return errno */
654
__attribute__((warn_unused_result))
655
error_t raise_privileges(void){
656
error_t old_errno = errno;
657
error_t ret_errno = 0;
658
if(seteuid(0) == -1){
665
/* Set effective and real user ID to 0. Return errno. */
666
__attribute__((warn_unused_result))
667
error_t raise_privileges_permanently(void){
668
error_t old_errno = errno;
669
error_t ret_errno = raise_privileges();
681
/* Set effective user ID to unprivileged saved user ID */
682
__attribute__((warn_unused_result))
683
error_t lower_privileges(void){
684
error_t old_errno = errno;
685
error_t ret_errno = 0;
686
if(seteuid(uid) == -1){
693
/* Lower privileges permanently */
694
__attribute__((warn_unused_result))
695
error_t lower_privileges_permanently(void){
696
error_t old_errno = errno;
697
error_t ret_errno = 0;
698
if(setuid(uid) == -1){
705
/* Helper function to add_local_route() and remove_local_route() */
1033
706
__attribute__((nonnull, warn_unused_result))
1034
static bool add_delete_local_route(const bool add,
707
static bool add_remove_local_route(const bool add,
1035
708
const char *address,
1036
709
AvahiIfIndex if_index){
1038
711
char helper[] = "mandos-client-iprouteadddel";
1039
712
char add_arg[] = "add";
1040
713
char delete_arg[] = "delete";
1041
char debug_flag[] = "--debug";
1042
714
char *pluginhelperdir = getenv("MANDOSPLUGINHELPERDIR");
1043
715
if(pluginhelperdir == NULL){
1187
850
__attribute__((nonnull, warn_unused_result))
1188
851
static bool add_local_route(const char *address,
1189
852
AvahiIfIndex if_index){
1191
fprintf_plus(stderr, "Adding route to %s\n", address);
1193
return add_delete_local_route(true, address, if_index);
853
return add_remove_local_route(true, address, if_index);
1196
856
__attribute__((nonnull, warn_unused_result))
1197
static bool delete_local_route(const char *address,
857
static bool remove_local_route(const char *address,
1198
858
AvahiIfIndex if_index){
1200
fprintf_plus(stderr, "Removing route to %s\n", address);
1202
return add_delete_local_route(false, address, if_index);
859
return add_remove_local_route(false, address, if_index);
1205
862
/* Called when a Mandos server is found */
2102
int devnull = (int)TEMP_FAILURE_RETRY(open("/dev/null", O_RDONLY));
2104
perror_plus("open(\"/dev/null\", O_RDONLY)");
1733
#if __GLIBC_PREREQ(2, 15)
2107
1734
int numhooks = scandirat(hookdir_fd, ".", &direntries,
2108
1735
runnable_hook, alphasort);
1736
#else /* not __GLIBC_PREREQ(2, 15) */
1737
int numhooks = scandir(hookdir, &direntries, runnable_hook,
1739
#endif /* not __GLIBC_PREREQ(2, 15) */
1740
#else /* not __GLIBC__ */
1741
int numhooks = scandir(hookdir, &direntries, runnable_hook,
1743
#endif /* not __GLIBC__ */
2109
1744
if(numhooks == -1){
2110
1745
perror_plus("scandir");
2114
1748
struct dirent *direntry;
1750
int devnull = (int)TEMP_FAILURE_RETRY(open("/dev/null", O_RDONLY));
1752
perror_plus("open(\"/dev/null\", O_RDONLY)");
2116
1755
for(int i = 0; i < numhooks; i++){
2117
1756
direntry = direntries[i];
2468
2105
int main(int argc, char *argv[]){
2469
mandos_context mc = { .server = NULL, .dh_bits = 0,
2470
#if GNUTLS_VERSION_NUMBER >= 0x030606
2471
.priority = "SECURE128:!CTYPE-X.509"
2472
":+CTYPE-RAWPK:!RSA:!VERS-ALL:+VERS-TLS1.3"
2474
#elif GNUTLS_VERSION_NUMBER < 0x030600
2475
.priority = "SECURE256:!CTYPE-X.509"
2476
":+CTYPE-OPENPGP:!RSA:+SIGN-DSA-SHA256",
2478
#error "Needs GnuTLS 3.6.6 or later, or before 3.6.0"
2480
.current_server = NULL, .interfaces = NULL,
2481
.interfaces_size = 0 };
2106
mandos_context mc = { .server = NULL, .dh_bits = 1024,
2107
.priority = "SECURE256:!CTYPE-X.509:"
2108
"+CTYPE-OPENPGP", .current_server = NULL,
2109
.interfaces = NULL, .interfaces_size = 0 };
2482
2110
AvahiSServiceBrowser *sb = NULL;
2483
2111
error_t ret_errno;
2550
2173
{ .name = "pubkey", .key = 'p',
2552
2175
.doc = "OpenPGP public key file base name",
2554
{ .name = "tls-privkey", .key = 't',
2556
#if GNUTLS_VERSION_NUMBER >= 0x030606
2557
.doc = "TLS private key file base name",
2559
.doc = "Dummy; ignored (requires GnuTLS 3.6.6)",
2562
{ .name = "tls-pubkey", .key = 'T',
2564
#if GNUTLS_VERSION_NUMBER >= 0x030606
2565
.doc = "TLS public key file base name",
2567
.doc = "Dummy; ignored (requires GnuTLS 3.6.6)",
2570
2177
{ .name = "dh-bits", .key = 129,
2572
2179
.doc = "Bit length of the prime number used in the"
2573
2180
" Diffie-Hellman key exchange",
2575
{ .name = "dh-params", .key = 134,
2577
.doc = "PEM-encoded PKCS#3 file with pre-generated parameters"
2578
" for the Diffie-Hellman key exchange",
2580
2182
{ .name = "priority", .key = 130,
2581
2183
.arg = "STRING",
2582
2184
.doc = "GnuTLS priority string for the TLS handshake",
3273
2826
free(interfaces_to_take_down);
3274
2827
free(interfaces_hooks);
3276
void clean_dir_at(int base, const char * const dirname,
3278
struct dirent **direntries = NULL;
3280
int dir_fd = (int)TEMP_FAILURE_RETRY(openat(base, dirname,
3286
perror_plus("open");
3289
int numentries = scandirat(dir_fd, ".", &direntries,
3290
notdotentries, alphasort);
3291
if(numentries >= 0){
3292
for(int i = 0; i < numentries; i++){
3294
fprintf_plus(stderr, "Unlinking \"%s/%s\"\n",
3295
dirname, direntries[i]->d_name);
3297
dret = unlinkat(dir_fd, direntries[i]->d_name, 0);
3299
if(errno == EISDIR){
3300
dret = unlinkat(dir_fd, direntries[i]->d_name,
3303
if((dret == -1) and (errno == ENOTEMPTY)
3304
and (strcmp(direntries[i]->d_name, "private-keys-v1.d")
3305
== 0) and (level == 0)){
3306
/* Recurse only in this special case */
3307
clean_dir_at(dir_fd, direntries[i]->d_name, level+1);
3310
if((dret == -1) and (errno != ENOENT)){
3311
fprintf_plus(stderr, "unlink(\"%s/%s\"): %s\n", dirname,
3312
direntries[i]->d_name, strerror(errno));
3315
free(direntries[i]);
3318
/* need to clean even if 0 because man page doesn't specify */
3320
dret = unlinkat(base, dirname, AT_REMOVEDIR);
3321
if(dret == -1 and errno != ENOENT){
3322
perror_plus("rmdir");
3325
perror_plus("scandirat");
3330
2829
/* Removes the GPGME temp directory and all files inside */
3331
2830
if(tempdir != NULL){
3332
clean_dir_at(-1, tempdir, 0);
2831
struct dirent **direntries = NULL;
2832
int tempdir_fd = (int)TEMP_FAILURE_RETRY(open(tempdir, O_RDONLY
2836
if(tempdir_fd == -1){
2837
perror_plus("open");
2840
#if __GLIBC_PREREQ(2, 15)
2841
int numentries = scandirat(tempdir_fd, ".", &direntries,
2842
notdotentries, alphasort);
2843
#else /* not __GLIBC_PREREQ(2, 15) */
2844
int numentries = scandir(tempdir, &direntries, notdotentries,
2846
#endif /* not __GLIBC_PREREQ(2, 15) */
2847
#else /* not __GLIBC__ */
2848
int numentries = scandir(tempdir, &direntries, notdotentries,
2850
#endif /* not __GLIBC__ */
2851
if(numentries >= 0){
2852
for(int i = 0; i < numentries; i++){
2853
ret = unlinkat(tempdir_fd, direntries[i]->d_name, 0);
2855
fprintf_plus(stderr, "unlinkat(open(\"%s\", O_RDONLY),"
2856
" \"%s\", 0): %s\n", tempdir,
2857
direntries[i]->d_name, strerror(errno));
2859
free(direntries[i]);
2862
/* need to clean even if 0 because man page doesn't specify */
2864
if(numentries == -1){
2865
perror_plus("scandir");
2867
ret = rmdir(tempdir);
2868
if(ret == -1 and errno != ENOENT){
2869
perror_plus("rmdir");
2872
TEMP_FAILURE_RETRY(close(tempdir_fd));