26
26
* along with this program. If not, see
27
27
* <http://www.gnu.org/licenses/>.
29
* Contact the authors at <mandos@fukt.bsnet.se>.
29
* Contact the authors at <mandos@recompile.se>.
32
32
/* Needed by GPGME, specifically gpgme_data_seek() */
33
#ifndef _LARGEFILE_SOURCE
33
34
#define _LARGEFILE_SOURCE
36
#ifndef _FILE_OFFSET_BITS
34
37
#define _FILE_OFFSET_BITS 64
36
40
#define _GNU_SOURCE /* TEMP_FAILURE_RETRY(), asprintf() */
38
42
#include <stdio.h> /* fprintf(), stderr, fwrite(),
39
stdout, ferror(), sscanf(),
41
#include <stdint.h> /* uint16_t, uint32_t */
43
stdout, ferror(), remove() */
44
#include <stdint.h> /* uint16_t, uint32_t, intptr_t */
42
45
#include <stddef.h> /* NULL, size_t, ssize_t */
43
#include <stdlib.h> /* free(), EXIT_SUCCESS, EXIT_FAILURE,
45
#include <stdbool.h> /* bool, true */
46
#include <stdlib.h> /* free(), EXIT_SUCCESS, srand(),
48
#include <stdbool.h> /* bool, false, true */
46
49
#include <string.h> /* memset(), strcmp(), strlen(),
47
50
strerror(), asprintf(), strcpy() */
48
#include <sys/ioctl.h> /* ioctl */
51
#include <sys/ioctl.h> /* ioctl */
49
52
#include <sys/types.h> /* socket(), inet_pton(), sockaddr,
50
53
sockaddr_in6, PF_INET6,
51
SOCK_STREAM, INET6_ADDRSTRLEN,
52
uid_t, gid_t, open(), opendir(),
54
#include <sys/stat.h> /* open() */
54
SOCK_STREAM, uid_t, gid_t, open(),
56
#include <sys/stat.h> /* open(), S_ISREG */
55
57
#include <sys/socket.h> /* socket(), struct sockaddr_in6,
56
struct in6_addr, inet_pton(),
58
inet_pton(), connect() */
58
59
#include <fcntl.h> /* open() */
59
60
#include <dirent.h> /* opendir(), struct dirent, readdir()
61
#include <inttypes.h> /* PRIu16, intmax_t, SCNdMAX */
62
#include <assert.h> /* assert() */
63
#include <errno.h> /* perror(), errno */
64
#include <time.h> /* nanosleep(), time() */
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() */
65
67
#include <net/if.h> /* ioctl, ifreq, SIOCGIFFLAGS, IFF_UP,
66
68
SIOCSIFFLAGS, if_indextoname(),
67
69
if_nametoindex(), IF_NAMESIZE */
68
#include <netinet/in.h>
70
#include <netinet/in.h> /* IN6_IS_ADDR_LINKLOCAL,
71
INET_ADDRSTRLEN, INET6_ADDRSTRLEN
69
73
#include <unistd.h> /* close(), SEEK_SET, off_t, write(),
70
getuid(), getgid(), setuid(),
72
#include <arpa/inet.h> /* inet_pton(), htons */
73
#include <iso646.h> /* not, and, or */
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 */
74
78
#include <argp.h> /* struct argp_option, error_t, struct
75
79
argp_state, struct argp,
76
80
argp_parse(), ARGP_KEY_ARG,
77
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(),
79
96
#include <sys/klog.h> /* klogctl() */
97
#endif /* __linux__ */
83
100
/* All Avahi types, constants and functions
146
207
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");
150
248
* Initialize GPGME.
152
static bool init_gpgme(mandos_context *mc, const char *seckey,
153
const char *pubkey, const char *tempdir){
250
static bool init_gpgme(const char *seckey, const char *pubkey,
251
const char *tempdir, mandos_context *mc){
155
252
gpgme_error_t rc;
156
253
gpgme_engine_info_t engine_info;
160
256
* Helper function to insert pub and seckey to the engine keyring.
162
258
bool import_key(const char *filename){
164
261
gpgme_data_t pgp_data;
166
263
fd = (int)TEMP_FAILURE_RETRY(open(filename, O_RDONLY));
172
269
rc = gpgme_data_new_from_fd(&pgp_data, fd);
173
270
if(rc != GPG_ERR_NO_ERROR){
174
fprintf(stderr, "bad gpgme_data_new_from_fd: %s: %s\n",
175
gpgme_strsource(rc), gpgme_strerror(rc));
271
fprintf_plus(stderr, "bad gpgme_data_new_from_fd: %s: %s\n",
272
gpgme_strsource(rc), gpgme_strerror(rc));
179
276
rc = gpgme_op_import(mc->ctx, pgp_data);
180
277
if(rc != GPG_ERR_NO_ERROR){
181
fprintf(stderr, "bad gpgme_op_import: %s: %s\n",
182
gpgme_strsource(rc), gpgme_strerror(rc));
278
fprintf_plus(stderr, "bad gpgme_op_import: %s: %s\n",
279
gpgme_strsource(rc), gpgme_strerror(rc));
186
283
ret = (int)TEMP_FAILURE_RETRY(close(fd));
285
perror_plus("close");
190
287
gpgme_data_release(pgp_data);
195
fprintf(stderr, "Initialize gpgme\n");
292
fprintf_plus(stderr, "Initializing GPGME\n");
199
296
gpgme_check_version(NULL);
200
297
rc = gpgme_engine_check_version(GPGME_PROTOCOL_OpenPGP);
201
298
if(rc != GPG_ERR_NO_ERROR){
202
fprintf(stderr, "bad gpgme_engine_check_version: %s: %s\n",
203
gpgme_strsource(rc), gpgme_strerror(rc));
299
fprintf_plus(stderr, "bad gpgme_engine_check_version: %s: %s\n",
300
gpgme_strsource(rc), gpgme_strerror(rc));
207
/* Set GPGME home directory for the OpenPGP engine only */
304
/* Set GPGME home directory for the OpenPGP engine only */
208
305
rc = gpgme_get_engine_info(&engine_info);
209
306
if(rc != GPG_ERR_NO_ERROR){
210
fprintf(stderr, "bad gpgme_get_engine_info: %s: %s\n",
211
gpgme_strsource(rc), gpgme_strerror(rc));
307
fprintf_plus(stderr, "bad gpgme_get_engine_info: %s: %s\n",
308
gpgme_strsource(rc), gpgme_strerror(rc));
214
311
while(engine_info != NULL){
507
621
__attribute__((unused)) const char *txt){}
509
623
/* Called when a Mandos server is found */
510
static int start_mandos_communication(const char *ip, uint16_t port,
624
static int start_mandos_communication(const char *ip, in_port_t port,
511
625
AvahiIfIndex if_index,
626
int af, mandos_context *mc){
627
int ret, tcp_sd = -1;
515
union { struct sockaddr in; struct sockaddr_in6 in6; } to;
630
struct sockaddr_in in;
631
struct sockaddr_in6 in6;
516
633
char *buffer = NULL;
517
char *decrypted_buffer;
634
char *decrypted_buffer = NULL;
518
635
size_t buffer_length = 0;
519
636
size_t buffer_capacity = 0;
520
ssize_t decrypted_buffer_size;
523
char interface[IF_NAMESIZE];
524
639
gnutls_session_t session;
526
ret = init_gnutls_session(mc, &session);
640
int pf; /* Protocol family */
657
fprintf_plus(stderr, "Bad address family: %d\n", af);
662
ret = init_gnutls_session(&session, mc);
532
fprintf(stderr, "Setting up a tcp connection to %s, port %" PRIu16
668
fprintf_plus(stderr, "Setting up a TCP connection to %s, port %"
669
PRIuMAX "\n", ip, (uintmax_t)port);
536
tcp_sd = socket(PF_INET6, SOCK_STREAM, 0);
672
tcp_sd = socket(pf, SOCK_STREAM, 0);
675
perror_plus("socket");
543
if(if_indextoname((unsigned int)if_index, interface) == NULL){
544
perror("if_indextoname");
547
fprintf(stderr, "Binding to interface %s\n", interface);
550
685
memset(&to, 0, sizeof(to));
551
to.in6.sin6_family = AF_INET6;
552
/* It would be nice to have a way to detect if we were passed an
553
IPv4 address here. Now we assume an IPv6 address. */
554
ret = inet_pton(AF_INET6, ip, &to.in6.sin6_addr);
687
to.in6.sin6_family = (sa_family_t)af;
688
ret = inet_pton(af, ip, &to.in6.sin6_addr);
690
to.in.sin_family = (sa_family_t)af;
691
ret = inet_pton(af, ip, &to.in.sin_addr);
695
perror_plus("inet_pton");
560
fprintf(stderr, "Bad address: %s\n", ip);
701
fprintf_plus(stderr, "Bad address: %s\n", ip);
563
to.in6.sin6_port = htons(port); /* Spurious warnings from
706
to.in6.sin6_port = htons(port);
707
if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */
708
(&to.in6.sin6_addr)){ /* -Wstrict-aliasing=2 or lower and
710
if(if_index == AVAHI_IF_UNSPEC){
711
fprintf_plus(stderr, "An IPv6 link-local address is"
712
" incomplete without a network interface\n");
716
/* Set the network interface number as scope */
717
to.in6.sin6_scope_id = (uint32_t)if_index;
720
to.in.sin_port = htons(port); /* Spurious warnings from
565
722
-Wunreachable-code */
567
to.in6.sin6_scope_id = (uint32_t)if_index;
570
fprintf(stderr, "Connection to: %s, port %" PRIu16 "\n", ip,
572
char addrstr[INET6_ADDRSTRLEN] = "";
573
if(inet_ntop(to.in6.sin6_family, &(to.in6.sin6_addr), addrstr,
574
sizeof(addrstr)) == NULL){
731
if(af == AF_INET6 and if_index != AVAHI_IF_UNSPEC){
732
char interface[IF_NAMESIZE];
733
if(if_indextoname((unsigned int)if_index, interface) == NULL){
734
perror_plus("if_indextoname");
736
fprintf_plus(stderr, "Connection to: %s%%%s, port %" PRIuMAX
737
"\n", ip, interface, (uintmax_t)port);
740
fprintf_plus(stderr, "Connection to: %s, port %" PRIuMAX "\n",
741
ip, (uintmax_t)port);
743
char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?
744
INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";
747
pcret = inet_ntop(af, &(to.in6.sin6_addr), addrstr,
750
pcret = inet_ntop(af, &(to.in.sin_addr), addrstr,
754
perror_plus("inet_ntop");
577
756
if(strcmp(addrstr, ip) != 0){
578
fprintf(stderr, "Canonical address form: %s\n", addrstr);
757
fprintf_plus(stderr, "Canonical address form: %s\n", addrstr);
583
ret = connect(tcp_sd, &to.in, sizeof(to));
768
ret = connect(tcp_sd, &to.in6, sizeof(to));
770
ret = connect(tcp_sd, &to.in, sizeof(to)); /* IPv4 */
773
if ((errno != ECONNREFUSED and errno != ENETUNREACH) or debug){
775
perror_plus("connect");
589
786
const char *out = mandos_protocol_version;
815
1107
case AVAHI_BROWSER_ALL_FOR_NOW:
816
1108
case AVAHI_BROWSER_CACHE_EXHAUSTED:
818
fprintf(stderr, "No Mandos server found, still searching...\n");
1110
fprintf_plus(stderr, "No Mandos server found, still"
1117
/* Signal handler that stops main loop after SIGTERM */
1118
static void handle_sigterm(int sig){
1123
signal_received = sig;
1124
int old_errno = errno;
1125
/* set main loop to exit */
1126
if(simple_poll != NULL){
1127
avahi_simple_poll_quit(simple_poll);
1132
bool get_flags(const char *ifname, struct ifreq *ifr){
1136
int s = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1139
perror_plus("socket");
1143
strcpy(ifr->ifr_name, ifname);
1144
ret = ioctl(s, SIOCGIFFLAGS, ifr);
1148
perror_plus("ioctl SIOCGIFFLAGS");
1156
bool good_flags(const char *ifname, const struct ifreq *ifr){
1158
/* Reject the loopback device */
1159
if(ifr->ifr_flags & IFF_LOOPBACK){
1161
fprintf_plus(stderr, "Rejecting loopback interface \"%s\"\n",
1166
/* Accept point-to-point devices only if connect_to is specified */
1167
if(connect_to != NULL and (ifr->ifr_flags & IFF_POINTOPOINT)){
1169
fprintf_plus(stderr, "Accepting point-to-point interface"
1170
" \"%s\"\n", ifname);
1174
/* Otherwise, reject non-broadcast-capable devices */
1175
if(not (ifr->ifr_flags & IFF_BROADCAST)){
1177
fprintf_plus(stderr, "Rejecting non-broadcast interface"
1178
" \"%s\"\n", ifname);
1182
/* Reject non-ARP interfaces (including dummy interfaces) */
1183
if(ifr->ifr_flags & IFF_NOARP){
1185
fprintf_plus(stderr, "Rejecting non-ARP interface \"%s\"\n",
1191
/* Accept this device */
1193
fprintf_plus(stderr, "Interface \"%s\" is good\n", ifname);
1199
* This function determines if a directory entry in /sys/class/net
1200
* corresponds to an acceptable network device.
1201
* (This function is passed to scandir(3) as a filter function.)
1203
int good_interface(const struct dirent *if_entry){
1204
if(if_entry->d_name[0] == '.'){
1209
if(not get_flags(if_entry->d_name, &ifr)){
1211
fprintf_plus(stderr, "Failed to get flags for interface "
1212
"\"%s\"\n", if_entry->d_name);
1217
if(not good_flags(if_entry->d_name, &ifr)){
1224
* This function determines if a network interface is up.
1226
bool interface_is_up(const char *interface){
1228
if(not get_flags(interface, &ifr)){
1230
fprintf_plus(stderr, "Failed to get flags for interface "
1231
"\"%s\"\n", interface);
1236
return (bool)(ifr.ifr_flags & IFF_UP);
1240
* This function determines if a network interface is running
1242
bool interface_is_running(const char *interface){
1244
if(not get_flags(interface, &ifr)){
1246
fprintf_plus(stderr, "Failed to get flags for interface "
1247
"\"%s\"\n", interface);
1252
return (bool)(ifr.ifr_flags & IFF_RUNNING);
1255
int notdotentries(const struct dirent *direntry){
1256
/* Skip "." and ".." */
1257
if(direntry->d_name[0] == '.'
1258
and (direntry->d_name[1] == '\0'
1259
or (direntry->d_name[1] == '.'
1260
and direntry->d_name[2] == '\0'))){
1266
/* Is this directory entry a runnable program? */
1267
int runnable_hook(const struct dirent *direntry){
1272
if((direntry->d_name)[0] == '\0'){
1277
sret = strspn(direntry->d_name, "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
1278
"abcdefghijklmnopqrstuvwxyz"
1281
if((direntry->d_name)[sret] != '\0'){
1282
/* Contains non-allowed characters */
1284
fprintf_plus(stderr, "Ignoring hook \"%s\" with bad name\n",
1290
char *fullname = NULL;
1291
ret = asprintf(&fullname, "%s/%s", hookdir, direntry->d_name);
1293
perror_plus("asprintf");
1297
ret = stat(fullname, &st);
1300
perror_plus("Could not stat hook");
1304
if(not (S_ISREG(st.st_mode))){
1305
/* Not a regular file */
1307
fprintf_plus(stderr, "Ignoring hook \"%s\" - not a file\n",
1312
if(not (st.st_mode & (S_IXUSR | S_IXGRP | S_IXOTH))){
1313
/* Not executable */
1315
fprintf_plus(stderr, "Ignoring hook \"%s\" - not executable\n",
1321
fprintf_plus(stderr, "Hook \"%s\" is acceptable\n",
1327
int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,
1328
mandos_context *mc){
1330
struct timespec now;
1331
struct timespec waited_time;
1332
intmax_t block_time;
1335
if(mc->current_server == NULL){
1337
fprintf_plus(stderr, "Wait until first server is found."
1340
ret = avahi_simple_poll_iterate(s, -1);
1343
fprintf_plus(stderr, "Check current_server if we should run"
1346
/* the current time */
1347
ret = clock_gettime(CLOCK_MONOTONIC, &now);
1349
perror_plus("clock_gettime");
1352
/* Calculating in ms how long time between now and server
1353
who we visted longest time ago. Now - last seen. */
1354
waited_time.tv_sec = (now.tv_sec
1355
- mc->current_server->last_seen.tv_sec);
1356
waited_time.tv_nsec = (now.tv_nsec
1357
- mc->current_server->last_seen.tv_nsec);
1358
/* total time is 10s/10,000ms.
1359
Converting to s from ms by dividing by 1,000,
1360
and ns to ms by dividing by 1,000,000. */
1361
block_time = ((retry_interval
1362
- ((intmax_t)waited_time.tv_sec * 1000))
1363
- ((intmax_t)waited_time.tv_nsec / 1000000));
1366
fprintf_plus(stderr, "Blocking for %" PRIdMAX " ms\n",
1370
if(block_time <= 0){
1371
ret = start_mandos_communication(mc->current_server->ip,
1372
mc->current_server->port,
1373
mc->current_server->if_index,
1374
mc->current_server->af, mc);
1376
avahi_simple_poll_quit(s);
1379
ret = clock_gettime(CLOCK_MONOTONIC,
1380
&mc->current_server->last_seen);
1382
perror_plus("clock_gettime");
1385
mc->current_server = mc->current_server->next;
1386
block_time = 0; /* Call avahi to find new Mandos
1387
servers, but don't block */
1390
ret = avahi_simple_poll_iterate(s, (int)block_time);
1393
if (ret > 0 or errno != EINTR){
1394
return (ret != 1) ? ret : 0;
1400
/* Set effective uid to 0, return errno */
1401
error_t raise_privileges(void){
1402
error_t old_errno = errno;
1403
error_t ret_errno = 0;
1404
if(seteuid(0) == -1){
1406
perror_plus("seteuid");
1412
/* Set effective and real user ID to 0. Return errno. */
1413
error_t raise_privileges_permanently(void){
1414
error_t old_errno = errno;
1415
error_t ret_errno = raise_privileges();
1420
if(setuid(0) == -1){
1422
perror_plus("seteuid");
1428
/* Set effective user ID to unprivileged saved user ID */
1429
error_t lower_privileges(void){
1430
error_t old_errno = errno;
1431
error_t ret_errno = 0;
1432
if(seteuid(uid) == -1){
1434
perror_plus("seteuid");
1440
/* Lower privileges permanently */
1441
error_t lower_privileges_permanently(void){
1442
error_t old_errno = errno;
1443
error_t ret_errno = 0;
1444
if(setuid(uid) == -1){
1446
perror_plus("setuid");
1452
bool run_network_hooks(const char *mode, const char *interface,
1454
struct dirent **direntries;
1455
struct dirent *direntry;
1457
int numhooks = scandir(hookdir, &direntries, runnable_hook,
1460
if(errno == ENOENT){
1462
fprintf_plus(stderr, "Network hook directory \"%s\" not"
1463
" found\n", hookdir);
1466
perror_plus("scandir");
1469
int devnull = open("/dev/null", O_RDONLY);
1470
for(int i = 0; i < numhooks; i++){
1471
direntry = direntries[i];
1472
char *fullname = NULL;
1473
ret = asprintf(&fullname, "%s/%s", hookdir, direntry->d_name);
1475
perror_plus("asprintf");
1479
fprintf_plus(stderr, "Running network hook \"%s\"\n",
1482
pid_t hook_pid = fork();
1485
/* Raise privileges */
1486
raise_privileges_permanently();
1491
perror_plus("setgid");
1493
/* Reset supplementary groups */
1495
ret = setgroups(0, NULL);
1497
perror_plus("setgroups");
1499
dup2(devnull, STDIN_FILENO);
1501
dup2(STDERR_FILENO, STDOUT_FILENO);
1502
ret = setenv("MANDOSNETHOOKDIR", hookdir, 1);
1504
perror_plus("setenv");
1507
ret = setenv("DEVICE", interface, 1);
1509
perror_plus("setenv");
1512
ret = setenv("VERBOSITY", debug ? "1" : "0", 1);
1514
perror_plus("setenv");
1517
ret = setenv("MODE", mode, 1);
1519
perror_plus("setenv");
1523
ret = asprintf(&delaystring, "%f", delay);
1525
perror_plus("asprintf");
1528
ret = setenv("DELAY", delaystring, 1);
1531
perror_plus("setenv");
1535
if(connect_to != NULL){
1536
ret = setenv("CONNECT", connect_to, 1);
1538
perror_plus("setenv");
1542
if(execl(fullname, direntry->d_name, mode, NULL) == -1){
1543
perror_plus("execl");
1544
_exit(EXIT_FAILURE);
1548
if(TEMP_FAILURE_RETRY(waitpid(hook_pid, &status, 0)) == -1){
1549
perror_plus("waitpid");
1553
if(WIFEXITED(status)){
1554
if(WEXITSTATUS(status) != 0){
1555
fprintf_plus(stderr, "Warning: network hook \"%s\" exited"
1556
" with status %d\n", direntry->d_name,
1557
WEXITSTATUS(status));
1561
} else if(WIFSIGNALED(status)){
1562
fprintf_plus(stderr, "Warning: network hook \"%s\" died by"
1563
" signal %d\n", direntry->d_name,
1568
fprintf_plus(stderr, "Warning: network hook \"%s\""
1569
" crashed\n", direntry->d_name);
1576
fprintf_plus(stderr, "Network hook \"%s\" ran successfully\n",
1585
error_t bring_up_interface(const char *const interface,
1588
error_t old_errno = errno;
1589
error_t ret_errno = 0;
1590
int ret, ret_setflags;
1591
struct ifreq network;
1592
unsigned int if_index = if_nametoindex(interface);
1594
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
1604
if(not interface_is_up(interface)){
1605
if(not get_flags(interface, &network) and debug){
1607
fprintf_plus(stderr, "Failed to get flags for interface "
1608
"\"%s\"\n", interface);
1611
network.ifr_flags |= IFF_UP;
1613
sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1616
perror_plus("socket");
1628
fprintf_plus(stderr, "Bringing up interface \"%s\"\n",
1632
/* Raise priviliges */
1636
/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO
1637
messages about the network interface to mess up the prompt */
1638
int ret_linux = klogctl(8, NULL, 5);
1639
bool restore_loglevel = true;
1640
if(ret_linux == -1){
1641
restore_loglevel = false;
1642
perror_plus("klogctl");
1644
#endif /* __linux__ */
1645
ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
1648
if(restore_loglevel){
1649
ret_linux = klogctl(7, NULL, 0);
1650
if(ret_linux == -1){
1651
perror_plus("klogctl");
1654
#endif /* __linux__ */
1656
/* Lower privileges */
1659
/* Close the socket */
1660
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1662
perror_plus("close");
1665
if(ret_setflags == -1){
1667
perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");
1672
fprintf_plus(stderr, "Interface \"%s\" is already up; good\n",
1676
/* Sleep checking until interface is running.
1677
Check every 0.25s, up to total time of delay */
1678
for(int i=0; i < delay * 4; i++){
1679
if(interface_is_running(interface)){
1682
struct timespec sleeptime = { .tv_nsec = 250000000 };
1683
ret = nanosleep(&sleeptime, NULL);
1684
if(ret == -1 and errno != EINTR){
1685
perror_plus("nanosleep");
1693
error_t take_down_interface(const char *const interface){
1695
error_t old_errno = errno;
1696
error_t ret_errno = 0;
1697
int ret, ret_setflags;
1698
struct ifreq network;
1699
unsigned int if_index = if_nametoindex(interface);
1701
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
1705
if(interface_is_up(interface)){
1706
if(not get_flags(interface, &network) and debug){
1708
fprintf_plus(stderr, "Failed to get flags for interface "
1709
"\"%s\"\n", interface);
1712
network.ifr_flags &= ~(short)IFF_UP; /* clear flag */
1714
sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1717
perror_plus("socket");
1723
fprintf_plus(stderr, "Taking down interface \"%s\"\n",
1727
/* Raise priviliges */
1730
ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
1733
/* Lower privileges */
1736
/* Close the socket */
1737
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1739
perror_plus("close");
1742
if(ret_setflags == -1){
1744
perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");
1749
fprintf_plus(stderr, "Interface \"%s\" is already down; odd\n",
824
1757
int main(int argc, char *argv[]){
1758
mandos_context mc = { .server = NULL, .dh_bits = 1024,
1759
.priority = "SECURE256:!CTYPE-X.509:"
1760
"+CTYPE-OPENPGP", .current_server = NULL,
1761
.interfaces = NULL, .interfaces_size = 0 };
825
1762
AvahiSServiceBrowser *sb = NULL;
828
1765
intmax_t tmpmax;
830
1767
int exitcode = EXIT_SUCCESS;
831
const char *interface = "eth0";
832
struct ifreq network;
836
char *connect_to = NULL;
1768
char *interfaces_to_take_down = NULL;
1769
size_t interfaces_to_take_down_size = 0;
837
1770
char tempdir[] = "/tmp/mandosXXXXXX";
838
1771
bool tempdir_created = false;
839
1772
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
840
1773
const char *seckey = PATHDIR "/" SECKEY;
841
1774
const char *pubkey = PATHDIR "/" PUBKEY;
1775
char *interfaces_hooks = NULL;
1776
size_t interfaces_hooks_size = 0;
843
mandos_context mc = { .simple_poll = NULL, .server = NULL,
844
.dh_bits = 1024, .priority = "SECURE256"
845
":!CTYPE-X.509:+CTYPE-OPENPGP" };
846
1778
bool gnutls_initialized = false;
847
1779
bool gpgme_initialized = false;
1781
double retry_interval = 10; /* 10s between trying a server and
1782
retrying the same server again */
1784
struct sigaction old_sigterm_action = { .sa_handler = SIG_DFL };
1785
struct sigaction sigterm_action = { .sa_handler = handle_sigterm };
1790
/* Lower any group privileges we might have, just to be safe */
1794
perror_plus("setgid");
1797
/* Lower user privileges (temporarily) */
1801
perror_plus("seteuid");
851
1809
struct argp_option options[] = {
915
1895
mc.priority = arg;
917
1897
case 131: /* --delay */
918
ret = sscanf(arg, "%lf%n", &delay, &numchars);
919
if(ret < 1 or arg[numchars] != '\0'){
920
fprintf(stderr, "Bad delay\n");
1899
delay = strtof(arg, &tmp);
1900
if(errno != 0 or tmp == arg or *tmp != '\0'){
1901
argp_error(state, "Bad delay");
1903
case 132: /* --retry */
1905
retry_interval = strtod(arg, &tmp);
1906
if(errno != 0 or tmp == arg or *tmp != '\0'
1907
or (retry_interval * 1000) > INT_MAX
1908
or retry_interval < 0){
1909
argp_error(state, "Bad retry interval");
1912
case 133: /* --network-hook-dir */
1916
* These reproduce what we would get without ARGP_NO_HELP
1918
case '?': /* --help */
1919
argp_state_help(state, state->out_stream,
1920
(ARGP_HELP_STD_HELP | ARGP_HELP_EXIT_ERR)
1921
& ~(unsigned int)ARGP_HELP_EXIT_OK);
1922
case -3: /* --usage */
1923
argp_state_help(state, state->out_stream,
1924
ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);
1925
case 'V': /* --version */
1926
fprintf_plus(state->out_stream, "%s\n", argp_program_version);
1927
exit(argp_err_exit_status);
929
1930
return ARGP_ERR_UNKNOWN;
934
1935
struct argp argp = { .options = options, .parser = parse_opt,
936
1937
.doc = "Mandos client -- Get and decrypt"
937
1938
" passwords from a Mandos server" };
938
ret = argp_parse(&argp, argc, argv, 0, 0, NULL);
939
if(ret == ARGP_ERR_UNKNOWN){
940
fprintf(stderr, "Unknown error while parsing arguments\n");
941
exitcode = EXIT_FAILURE;
946
/* If the interface is down, bring it up */
949
/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO
950
messages to mess up the prompt */
951
ret = klogctl(8, NULL, 5);
957
sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
960
exitcode = EXIT_FAILURE;
962
ret = klogctl(7, NULL, 0);
969
strcpy(network.ifr_name, interface);
970
ret = ioctl(sd, SIOCGIFFLAGS, &network);
972
perror("ioctl SIOCGIFFLAGS");
974
ret = klogctl(7, NULL, 0);
979
exitcode = EXIT_FAILURE;
982
if((network.ifr_flags & IFF_UP) == 0){
983
network.ifr_flags |= IFF_UP;
984
ret = ioctl(sd, SIOCSIFFLAGS, &network);
986
perror("ioctl SIOCSIFFLAGS");
987
exitcode = EXIT_FAILURE;
989
ret = klogctl(7, NULL, 0);
1939
ret = argp_parse(&argp, argc, argv,
1940
ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);
1947
perror_plus("argp_parse");
1948
exitcode = EX_OSERR;
1951
exitcode = EX_USAGE;
1957
/* Work around Debian bug #633582:
1958
<http://bugs.debian.org/633582> */
1960
/* Re-raise priviliges */
1961
if(raise_privileges() == 0){
1964
if(strcmp(seckey, PATHDIR "/" SECKEY) == 0){
1965
int seckey_fd = open(seckey, O_RDONLY);
1966
if(seckey_fd == -1){
1967
perror_plus("open");
1969
ret = (int)TEMP_FAILURE_RETRY(fstat(seckey_fd, &st));
1971
perror_plus("fstat");
1973
if(S_ISREG(st.st_mode)
1974
and st.st_uid == 0 and st.st_gid == 0){
1975
ret = fchown(seckey_fd, uid, gid);
1977
perror_plus("fchown");
1981
TEMP_FAILURE_RETRY(close(seckey_fd));
1985
if(strcmp(pubkey, PATHDIR "/" PUBKEY) == 0){
1986
int pubkey_fd = open(pubkey, O_RDONLY);
1987
if(pubkey_fd == -1){
1988
perror_plus("open");
1990
ret = (int)TEMP_FAILURE_RETRY(fstat(pubkey_fd, &st));
1992
perror_plus("fstat");
1994
if(S_ISREG(st.st_mode)
1995
and st.st_uid == 0 and st.st_gid == 0){
1996
ret = fchown(pubkey_fd, uid, gid);
1998
perror_plus("fchown");
2002
TEMP_FAILURE_RETRY(close(pubkey_fd));
2006
/* Lower privileges */
2010
perror_plus("seteuid");
2015
/* Remove empty interface names */
2017
char *interface = NULL;
2018
while((interface = argz_next(mc.interfaces, mc.interfaces_size,
2020
if(if_nametoindex(interface) == 0){
2021
if(interface[0] != '\0' and strcmp(interface, "none") != 0){
2022
fprintf_plus(stderr, "Not using nonexisting interface"
2023
" \"%s\"\n", interface);
2025
argz_delete(&mc.interfaces, &mc.interfaces_size, interface);
2031
/* Run network hooks */
2034
if(mc.interfaces != NULL){
2035
interfaces_hooks = malloc(mc.interfaces_size);
2036
if(interfaces_hooks == NULL){
2037
perror_plus("malloc");
997
/* sleep checking until interface is running */
998
for(int i=0; i < delay * 4; i++){
999
ret = ioctl(sd, SIOCGIFFLAGS, &network);
1001
perror("ioctl SIOCGIFFLAGS");
1002
} else if(network.ifr_flags & IFF_RUNNING){
1005
struct timespec sleeptime = { .tv_nsec = 250000000 };
1006
ret = nanosleep(&sleeptime, NULL);
1007
if(ret == -1 and errno != EINTR){
1008
perror("nanosleep");
1011
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1016
/* Restores kernel loglevel to default */
1017
ret = klogctl(7, NULL, 0);
1037
ret = init_gnutls_global(&mc, pubkey, seckey);
1039
fprintf(stderr, "init_gnutls_global failed\n");
1040
exitcode = EXIT_FAILURE;
2040
memcpy(interfaces_hooks, mc.interfaces, mc.interfaces_size);
2041
interfaces_hooks_size = mc.interfaces_size;
2042
argz_stringify(interfaces_hooks, interfaces_hooks_size,
2045
if(not run_network_hooks("start", interfaces_hooks != NULL ?
2046
interfaces_hooks : "", delay)){
2052
avahi_set_log_function(empty_log);
2055
/* Initialize Avahi early so avahi_simple_poll_quit() can be called
2056
from the signal handler */
2057
/* Initialize the pseudo-RNG for Avahi */
2058
srand((unsigned int) time(NULL));
2059
simple_poll = avahi_simple_poll_new();
2060
if(simple_poll == NULL){
2061
fprintf_plus(stderr,
2062
"Avahi: Failed to create simple poll object.\n");
2063
exitcode = EX_UNAVAILABLE;
2067
sigemptyset(&sigterm_action.sa_mask);
2068
ret = sigaddset(&sigterm_action.sa_mask, SIGINT);
2070
perror_plus("sigaddset");
2071
exitcode = EX_OSERR;
2074
ret = sigaddset(&sigterm_action.sa_mask, SIGHUP);
2076
perror_plus("sigaddset");
2077
exitcode = EX_OSERR;
2080
ret = sigaddset(&sigterm_action.sa_mask, SIGTERM);
2082
perror_plus("sigaddset");
2083
exitcode = EX_OSERR;
2086
/* Need to check if the handler is SIG_IGN before handling:
2087
| [[info:libc:Initial Signal Actions]] |
2088
| [[info:libc:Basic Signal Handling]] |
2090
ret = sigaction(SIGINT, NULL, &old_sigterm_action);
2092
perror_plus("sigaction");
2095
if(old_sigterm_action.sa_handler != SIG_IGN){
2096
ret = sigaction(SIGINT, &sigterm_action, NULL);
2098
perror_plus("sigaction");
2099
exitcode = EX_OSERR;
2103
ret = sigaction(SIGHUP, NULL, &old_sigterm_action);
2105
perror_plus("sigaction");
2108
if(old_sigterm_action.sa_handler != SIG_IGN){
2109
ret = sigaction(SIGHUP, &sigterm_action, NULL);
2111
perror_plus("sigaction");
2112
exitcode = EX_OSERR;
2116
ret = sigaction(SIGTERM, NULL, &old_sigterm_action);
2118
perror_plus("sigaction");
2121
if(old_sigterm_action.sa_handler != SIG_IGN){
2122
ret = sigaction(SIGTERM, &sigterm_action, NULL);
2124
perror_plus("sigaction");
2125
exitcode = EX_OSERR;
2130
/* If no interfaces were specified, make a list */
2131
if(mc.interfaces == NULL){
2132
struct dirent **direntries;
2133
/* Look for any good interfaces */
2134
ret = scandir(sys_class_net, &direntries, good_interface,
2137
/* Add all found interfaces to interfaces list */
2138
for(int i = 0; i < ret; ++i){
2139
ret_errno = argz_add(&mc.interfaces, &mc.interfaces_size,
2140
direntries[i]->d_name);
2142
perror_plus("argz_add");
2146
fprintf_plus(stderr, "Will use interface \"%s\"\n",
2147
direntries[i]->d_name);
2153
fprintf_plus(stderr, "Could not find a network interface\n");
2154
exitcode = EXIT_FAILURE;
2159
/* If we only got one interface, explicitly use only that one */
2160
if(argz_count(mc.interfaces, mc.interfaces_size) == 1){
2162
fprintf_plus(stderr, "Using only interface \"%s\"\n",
2165
if_index = (AvahiIfIndex)if_nametoindex(mc.interfaces);
2168
/* Bring up interfaces which are down */
2169
if(not (argz_count(mc.interfaces, mc.interfaces_size) == 1
2170
and strcmp(mc.interfaces, "none") == 0)){
2171
char *interface = NULL;
2172
while((interface = argz_next(mc.interfaces, mc.interfaces_size,
2174
bool interface_was_up = interface_is_up(interface);
2175
ret = bring_up_interface(interface, delay);
2176
if(not interface_was_up){
2179
perror_plus("Failed to bring up interface");
2181
ret_errno = argz_add(&interfaces_to_take_down,
2182
&interfaces_to_take_down_size,
2187
free(mc.interfaces);
2188
mc.interfaces = NULL;
2189
mc.interfaces_size = 0;
2190
if(debug and (interfaces_to_take_down == NULL)){
2191
fprintf_plus(stderr, "No interfaces were brought up\n");
2199
ret = init_gnutls_global(pubkey, seckey, &mc);
2201
fprintf_plus(stderr, "init_gnutls_global failed\n");
2202
exitcode = EX_UNAVAILABLE;
1043
2205
gnutls_initialized = true;
1046
2212
if(mkdtemp(tempdir) == NULL){
2213
perror_plus("mkdtemp");
1050
2216
tempdir_created = true;
1052
if(not init_gpgme(&mc, pubkey, seckey, tempdir)){
1053
fprintf(stderr, "init_gpgme failed\n");
1054
exitcode = EXIT_FAILURE;
2222
if(not init_gpgme(pubkey, seckey, tempdir, &mc)){
2223
fprintf_plus(stderr, "init_gpgme failed\n");
2224
exitcode = EX_UNAVAILABLE;
1057
2227
gpgme_initialized = true;
1060
if_index = (AvahiIfIndex) if_nametoindex(interface);
1062
fprintf(stderr, "No such interface: \"%s\"\n", interface);
1063
exitcode = EXIT_FAILURE;