9
9
* "browse_callback", and parts of "main".
11
11
* Everything else is
12
* Copyright © 2008-2019 Teddy Hogeborn
13
* Copyright © 2008-2019 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
time_t keytime = keystat.st_mtim.tv_sec;
400
if(stime(&keytime) != 0){
401
perror_plus("stime");
403
ret = lower_privileges();
406
perror_plus("Failed to lower privileges");
410
294
rc = gpgme_data_new_from_fd(&pgp_data, fd);
411
295
if(rc != GPG_ERR_NO_ERROR){
412
296
fprintf_plus(stderr, "bad gpgme_data_new_from_fd: %s: %s\n",
420
304
gpgme_strsource(rc), gpgme_strerror(rc));
424
gpgme_import_result_t import_result
425
= gpgme_op_import_result(mc->ctx);
426
if((import_result->imported < 1
427
or import_result->not_imported > 0)
428
and import_result->unchanged == 0){
429
fprintf_plus(stderr, "bad gpgme_op_import_results:\n");
431
"The total number of considered keys: %d\n",
432
import_result->considered);
434
"The number of keys without user ID: %d\n",
435
import_result->no_user_id);
437
"The total number of imported keys: %d\n",
438
import_result->imported);
439
fprintf_plus(stderr, "The number of imported RSA keys: %d\n",
440
import_result->imported_rsa);
441
fprintf_plus(stderr, "The number of unchanged keys: %d\n",
442
import_result->unchanged);
443
fprintf_plus(stderr, "The number of new user IDs: %d\n",
444
import_result->new_user_ids);
445
fprintf_plus(stderr, "The number of new sub keys: %d\n",
446
import_result->new_sub_keys);
447
fprintf_plus(stderr, "The number of new signatures: %d\n",
448
import_result->new_signatures);
449
fprintf_plus(stderr, "The number of new revocations: %d\n",
450
import_result->new_revocations);
452
"The total number of secret keys read: %d\n",
453
import_result->secret_read);
455
"The number of imported secret keys: %d\n",
456
import_result->secret_imported);
458
"The number of unchanged secret keys: %d\n",
459
import_result->secret_unchanged);
460
fprintf_plus(stderr, "The number of keys not imported: %d\n",
461
import_result->not_imported);
462
for(gpgme_import_status_t import_status
463
= import_result->imports;
464
import_status != NULL;
465
import_status = import_status->next){
466
fprintf_plus(stderr, "Import status for key: %s\n",
468
if(import_status->result != GPG_ERR_NO_ERROR){
469
fprintf_plus(stderr, "Import result: %s: %s\n",
470
gpgme_strsource(import_status->result),
471
gpgme_strerror(import_status->result));
473
fprintf_plus(stderr, "Key status:\n");
475
import_status->status & GPGME_IMPORT_NEW
476
? "The key was new.\n"
477
: "The key was not new.\n");
479
import_status->status & GPGME_IMPORT_UID
480
? "The key contained new user IDs.\n"
481
: "The key did not contain new user IDs.\n");
483
import_status->status & GPGME_IMPORT_SIG
484
? "The key contained new signatures.\n"
485
: "The key did not contain new signatures.\n");
487
import_status->status & GPGME_IMPORT_SUBKEY
488
? "The key contained new sub keys.\n"
489
: "The key did not contain new sub keys.\n");
491
import_status->status & GPGME_IMPORT_SECRET
492
? "The key contained a secret key.\n"
493
: "The key did not contain a secret key.\n");
308
ret = (int)TEMP_FAILURE_RETRY(close(fd));
501
310
perror_plus("close");
603
414
if(result == NULL){
604
415
fprintf_plus(stderr, "gpgme_op_decrypt_result failed\n");
606
if(result->unsupported_algorithm != NULL) {
607
fprintf_plus(stderr, "Unsupported algorithm: %s\n",
608
result->unsupported_algorithm);
610
fprintf_plus(stderr, "Wrong key usage: %s\n",
611
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);
612
421
if(result->file_name != NULL){
613
422
fprintf_plus(stderr, "File name: %s\n", result->file_name);
616
for(gpgme_recipient_t r = result->recipients; r != NULL;
424
gpgme_recipient_t recipient;
425
recipient = result->recipients;
426
while(recipient != NULL){
618
427
fprintf_plus(stderr, "Public key algorithm: %s\n",
619
gpgme_pubkey_algo_name(r->pubkey_algo));
620
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);
621
431
fprintf_plus(stderr, "Secret key available: %s\n",
622
r->status == GPG_ERR_NO_SECKEY ? "No" : "Yes");
432
recipient->status == GPG_ERR_NO_SECKEY
434
recipient = recipient->next;
725
538
if(ret != GNUTLS_E_SUCCESS){
726
539
fprintf_plus(stderr, "GnuTLS memory error: %s\n",
727
540
safer_gnutls_strerror(ret));
541
gnutls_global_deinit();
732
fprintf_plus(stderr, "Attempting to use public key %s and"
733
" 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",
738
#if GNUTLS_VERSION_NUMBER >= 0x030606
739
ret = gnutls_certificate_set_rawpk_key_file
740
(mc->cred, pubkeyfilename, seckeyfilename,
741
GNUTLS_X509_FMT_PEM, /* format */
744
GNUTLS_KEY_DIGITAL_SIGNATURE | GNUTLS_KEY_KEY_ENCIPHERMENT,
746
0, /* names_length */
748
GNUTLS_PKCS_PLAIN | GNUTLS_PKCS_NULL_PASSWORD,
749
0); /* pkcs11_flags */
750
#elif GNUTLS_VERSION_NUMBER < 0x030600
751
552
ret = gnutls_certificate_set_openpgp_key_file
752
553
(mc->cred, pubkeyfilename, seckeyfilename,
753
554
GNUTLS_OPENPGP_FMT_BASE64);
755
#error "Needs GnuTLS 3.6.6 or later, or before 3.6.0"
757
555
if(ret != GNUTLS_E_SUCCESS){
758
556
fprintf_plus(stderr,
759
"Error[%d] while reading the key pair ('%s',"
557
"Error[%d] while reading the OpenPGP key pair ('%s',"
760
558
" '%s')\n", ret, pubkeyfilename, seckeyfilename);
761
559
fprintf_plus(stderr, "The GnuTLS error is: %s\n",
762
560
safer_gnutls_strerror(ret));
771
569
safer_gnutls_strerror(ret));
774
/* If a Diffie-Hellman parameters file was given, try to use it */
775
if(dhparamsfilename != NULL){
776
gnutls_datum_t params = { .data = NULL, .size = 0 };
778
int dhpfile = open(dhparamsfilename, O_RDONLY);
781
dhparamsfilename = NULL;
784
size_t params_capacity = 0;
786
params_capacity = incbuffer((char **)¶ms.data,
788
(size_t)params_capacity);
789
if(params_capacity == 0){
790
perror_plus("incbuffer");
793
dhparamsfilename = NULL;
796
ssize_t bytes_read = read(dhpfile,
797
params.data + params.size,
803
/* check bytes_read for failure */
808
dhparamsfilename = NULL;
811
params.size += (unsigned int)bytes_read;
813
ret = close(dhpfile);
815
perror_plus("close");
817
if(params.data == NULL){
818
dhparamsfilename = NULL;
820
if(dhparamsfilename == NULL){
823
ret = gnutls_dh_params_import_pkcs3(mc->dh_params, ¶ms,
824
GNUTLS_X509_FMT_PEM);
825
if(ret != GNUTLS_E_SUCCESS){
826
fprintf_plus(stderr, "Failed to parse DH parameters in file"
827
" \"%s\": %s\n", dhparamsfilename,
828
safer_gnutls_strerror(ret));
829
dhparamsfilename = NULL;
834
if(dhparamsfilename == NULL){
835
if(mc->dh_bits == 0){
836
#if GNUTLS_VERSION_NUMBER < 0x030600
837
/* Find out the optimal number of DH bits */
838
/* Try to read the private key file */
839
gnutls_datum_t buffer = { .data = NULL, .size = 0 };
841
int secfile = open(seckeyfilename, O_RDONLY);
846
size_t buffer_capacity = 0;
848
buffer_capacity = incbuffer((char **)&buffer.data,
850
(size_t)buffer_capacity);
851
if(buffer_capacity == 0){
852
perror_plus("incbuffer");
857
ssize_t bytes_read = read(secfile,
858
buffer.data + buffer.size,
864
/* check bytes_read for failure */
871
buffer.size += (unsigned int)bytes_read;
875
/* If successful, use buffer to parse private key */
876
gnutls_sec_param_t sec_param = GNUTLS_SEC_PARAM_ULTRA;
877
if(buffer.data != NULL){
879
gnutls_openpgp_privkey_t privkey = NULL;
880
ret = gnutls_openpgp_privkey_init(&privkey);
881
if(ret != GNUTLS_E_SUCCESS){
882
fprintf_plus(stderr, "Error initializing OpenPGP key"
884
safer_gnutls_strerror(ret));
888
ret = gnutls_openpgp_privkey_import
889
(privkey, &buffer, GNUTLS_OPENPGP_FMT_BASE64, "", 0);
890
if(ret != GNUTLS_E_SUCCESS){
891
fprintf_plus(stderr, "Error importing OpenPGP key : %s",
892
safer_gnutls_strerror(ret));
898
/* Use private key to suggest an appropriate
900
sec_param = gnutls_openpgp_privkey_sec_param(privkey);
901
gnutls_openpgp_privkey_deinit(privkey);
903
fprintf_plus(stderr, "This OpenPGP key implies using"
904
" a GnuTLS security parameter \"%s\".\n",
905
safe_string(gnutls_sec_param_get_name
911
if(sec_param == GNUTLS_SEC_PARAM_UNKNOWN){
912
/* Err on the side of caution */
913
sec_param = GNUTLS_SEC_PARAM_ULTRA;
915
fprintf_plus(stderr, "Falling back to security parameter"
917
safe_string(gnutls_sec_param_get_name
922
unsigned int uret = gnutls_sec_param_to_pk_bits(GNUTLS_PK_DH, sec_param);
926
fprintf_plus(stderr, "A \"%s\" GnuTLS security parameter"
927
" implies %u DH bits; using that.\n",
928
safe_string(gnutls_sec_param_get_name
933
fprintf_plus(stderr, "Failed to get implied number of DH"
934
" bits for security parameter \"%s\"): %s\n",
935
safe_string(gnutls_sec_param_get_name
937
safer_gnutls_strerror(ret));
941
} else { /* dh_bits != 0 */
943
fprintf_plus(stderr, "DH bits explicitly set to %u\n",
946
ret = gnutls_dh_params_generate2(mc->dh_params, mc->dh_bits);
947
if(ret != GNUTLS_E_SUCCESS){
948
fprintf_plus(stderr, "Error in GnuTLS prime generation (%u"
949
" bits): %s\n", mc->dh_bits,
950
safer_gnutls_strerror(ret));
953
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);
961
585
gnutls_certificate_free_credentials(mc->cred);
586
gnutls_global_deinit();
962
587
gnutls_dh_params_deinit(mc->dh_params);
1030
650
static void empty_log(__attribute__((unused)) AvahiLogLevel level,
1031
651
__attribute__((unused)) const char *txt){}
1033
/* 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() */
1034
706
__attribute__((nonnull, warn_unused_result))
1035
static bool add_delete_local_route(const bool add,
707
static bool add_remove_local_route(const bool add,
1036
708
const char *address,
1037
709
AvahiIfIndex if_index){
1039
711
char helper[] = "mandos-client-iprouteadddel";
1040
712
char add_arg[] = "add";
1041
713
char delete_arg[] = "delete";
1042
char debug_flag[] = "--debug";
1043
714
char *pluginhelperdir = getenv("MANDOSPLUGINHELPERDIR");
1044
715
if(pluginhelperdir == NULL){
1181
850
__attribute__((nonnull, warn_unused_result))
1182
851
static bool add_local_route(const char *address,
1183
852
AvahiIfIndex if_index){
1185
fprintf_plus(stderr, "Adding route to %s\n", address);
1187
return add_delete_local_route(true, address, if_index);
853
return add_remove_local_route(true, address, if_index);
1190
856
__attribute__((nonnull, warn_unused_result))
1191
static bool delete_local_route(const char *address,
857
static bool remove_local_route(const char *address,
1192
858
AvahiIfIndex if_index){
1194
fprintf_plus(stderr, "Removing route to %s\n", address);
1196
return add_delete_local_route(false, address, if_index);
859
return add_remove_local_route(false, address, if_index);
1199
862
/* Called when a Mandos server is found */
2096
int devnull = (int)TEMP_FAILURE_RETRY(open("/dev/null", O_RDONLY));
2098
perror_plus("open(\"/dev/null\", O_RDONLY)");
1733
#if __GLIBC_PREREQ(2, 15)
2101
1734
int numhooks = scandirat(hookdir_fd, ".", &direntries,
2102
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__ */
2103
1744
if(numhooks == -1){
2104
1745
perror_plus("scandir");
2108
1748
struct dirent *direntry;
1750
int devnull = (int)TEMP_FAILURE_RETRY(open("/dev/null", O_RDONLY));
1752
perror_plus("open(\"/dev/null\", O_RDONLY)");
2110
1755
for(int i = 0; i < numhooks; i++){
2111
1756
direntry = direntries[i];
2462
2105
int main(int argc, char *argv[]){
2463
mandos_context mc = { .server = NULL, .dh_bits = 0,
2464
#if GNUTLS_VERSION_NUMBER >= 0x030606
2465
.priority = "SECURE128:!CTYPE-X.509"
2466
":+CTYPE-RAWPK:!RSA:!VERS-ALL:+VERS-TLS1.3"
2468
#elif GNUTLS_VERSION_NUMBER < 0x030600
2469
.priority = "SECURE256:!CTYPE-X.509"
2470
":+CTYPE-OPENPGP:!RSA:+SIGN-DSA-SHA256",
2472
#error "Needs GnuTLS 3.6.6 or later, or before 3.6.0"
2474
.current_server = NULL, .interfaces = NULL,
2475
.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 };
2476
2110
AvahiSServiceBrowser *sb = NULL;
2477
2111
error_t ret_errno;
2544
2173
{ .name = "pubkey", .key = 'p',
2546
2175
.doc = "OpenPGP public key file base name",
2548
{ .name = "tls-privkey", .key = 't',
2550
#if GNUTLS_VERSION_NUMBER >= 0x030606
2551
.doc = "TLS private key file base name",
2553
.doc = "Dummy; ignored (requires GnuTLS 3.6.6)",
2556
{ .name = "tls-pubkey", .key = 'T',
2558
#if GNUTLS_VERSION_NUMBER >= 0x030606
2559
.doc = "TLS public key file base name",
2561
.doc = "Dummy; ignored (requires GnuTLS 3.6.6)",
2564
2177
{ .name = "dh-bits", .key = 129,
2566
2179
.doc = "Bit length of the prime number used in the"
2567
2180
" Diffie-Hellman key exchange",
2569
{ .name = "dh-params", .key = 134,
2571
.doc = "PEM-encoded PKCS#3 file with pre-generated parameters"
2572
" for the Diffie-Hellman key exchange",
2574
2182
{ .name = "priority", .key = 130,
2575
2183
.arg = "STRING",
2576
2184
.doc = "GnuTLS priority string for the TLS handshake",
3267
2826
free(interfaces_to_take_down);
3268
2827
free(interfaces_hooks);
3270
void clean_dir_at(int base, const char * const dirname,
3272
struct dirent **direntries = NULL;
3274
int dir_fd = (int)TEMP_FAILURE_RETRY(openat(base, dirname,
3280
perror_plus("open");
3283
int numentries = scandirat(dir_fd, ".", &direntries,
3284
notdotentries, alphasort);
3285
if(numentries >= 0){
3286
for(int i = 0; i < numentries; i++){
3288
fprintf_plus(stderr, "Unlinking \"%s/%s\"\n",
3289
dirname, direntries[i]->d_name);
3291
dret = unlinkat(dir_fd, direntries[i]->d_name, 0);
3293
if(errno == EISDIR){
3294
dret = unlinkat(dir_fd, direntries[i]->d_name,
3297
if((dret == -1) and (errno == ENOTEMPTY)
3298
and (strcmp(direntries[i]->d_name, "private-keys-v1.d")
3299
== 0) and (level == 0)){
3300
/* Recurse only in this special case */
3301
clean_dir_at(dir_fd, direntries[i]->d_name, level+1);
3304
if((dret == -1) and (errno != ENOENT)){
3305
fprintf_plus(stderr, "unlink(\"%s/%s\"): %s\n", dirname,
3306
direntries[i]->d_name, strerror(errno));
3309
free(direntries[i]);
3312
/* need to clean even if 0 because man page doesn't specify */
3314
dret = unlinkat(base, dirname, AT_REMOVEDIR);
3315
if(dret == -1 and errno != ENOENT){
3316
perror_plus("rmdir");
3319
perror_plus("scandirat");
3324
2829
/* Removes the GPGME temp directory and all files inside */
3325
2830
if(tempdir != NULL){
3326
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));