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
/* 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,
694
ret = init_gnutls_session(&session, mc);
532
fprintf(stderr, "Setting up a tcp connection to %s, port %" PRIu16
700
fprintf_plus(stderr, "Setting up a TCP connection to %s, port %"
701
PRIuMAX "\n", ip, (uintmax_t)port);
536
tcp_sd = socket(PF_INET6, SOCK_STREAM, 0);
704
tcp_sd = socket(pf, SOCK_STREAM, 0);
707
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
717
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);
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");
560
fprintf(stderr, "Bad address: %s\n", ip);
563
to.in6.sin6_port = htons(port); /* Spurious warnings from
565
-Wunreachable-code */
733
fprintf_plus(stderr, "Bad address: %s\n", ip);
738
to.in6.sin6_port = htons(port);
740
#pragma GCC diagnostic push
741
#pragma GCC diagnostic ignored "-Wstrict-aliasing"
743
if(IN6_IS_ADDR_LINKLOCAL /* Spurious warnings from */
744
(&to.in6.sin6_addr)){ /* -Wstrict-aliasing=2 or lower */
746
#pragma GCC diagnostic pop
748
if(if_index == AVAHI_IF_UNSPEC){
749
fprintf_plus(stderr, "An IPv6 link-local address is"
750
" incomplete without a network interface\n");
754
/* Set the network interface number as scope */
755
to.in6.sin6_scope_id = (uint32_t)if_index;
758
to.in.sin_port = htons(port);
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){
767
if(af == AF_INET6 and if_index != AVAHI_IF_UNSPEC){
768
char interface[IF_NAMESIZE];
769
if(if_indextoname((unsigned int)if_index, interface) == NULL){
770
perror_plus("if_indextoname");
772
fprintf_plus(stderr, "Connection to: %s%%%s, port %" PRIuMAX
773
"\n", ip, interface, (uintmax_t)port);
776
fprintf_plus(stderr, "Connection to: %s, port %" PRIuMAX "\n",
777
ip, (uintmax_t)port);
779
char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?
780
INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";
783
pcret = inet_ntop(af, &(to.in6.sin6_addr), addrstr,
786
pcret = inet_ntop(af, &(to.in.sin_addr), addrstr,
790
perror_plus("inet_ntop");
577
792
if(strcmp(addrstr, ip) != 0){
578
fprintf(stderr, "Canonical address form: %s\n", addrstr);
793
fprintf_plus(stderr, "Canonical address form: %s\n", addrstr);
583
ret = connect(tcp_sd, &to.in, sizeof(to));
804
ret = connect(tcp_sd, &to.in6, sizeof(to));
806
ret = connect(tcp_sd, &to.in, sizeof(to)); /* IPv4 */
809
if ((errno != ECONNREFUSED and errno != ENETUNREACH) or debug){
811
perror_plus("connect");
589
822
const char *out = mandos_protocol_version;
815
1143
case AVAHI_BROWSER_ALL_FOR_NOW:
816
1144
case AVAHI_BROWSER_CACHE_EXHAUSTED:
818
fprintf(stderr, "No Mandos server found, still searching...\n");
1146
fprintf_plus(stderr, "No Mandos server found, still"
1153
/* Signal handler that stops main loop after SIGTERM */
1154
static void handle_sigterm(int sig){
1159
signal_received = sig;
1160
int old_errno = errno;
1161
/* set main loop to exit */
1162
if(simple_poll != NULL){
1163
avahi_simple_poll_quit(simple_poll);
1168
bool get_flags(const char *ifname, struct ifreq *ifr){
1172
int s = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1175
perror_plus("socket");
1179
strcpy(ifr->ifr_name, ifname);
1180
ret = ioctl(s, SIOCGIFFLAGS, ifr);
1184
perror_plus("ioctl SIOCGIFFLAGS");
1192
bool good_flags(const char *ifname, const struct ifreq *ifr){
1194
/* Reject the loopback device */
1195
if(ifr->ifr_flags & IFF_LOOPBACK){
1197
fprintf_plus(stderr, "Rejecting loopback interface \"%s\"\n",
1202
/* Accept point-to-point devices only if connect_to is specified */
1203
if(connect_to != NULL and (ifr->ifr_flags & IFF_POINTOPOINT)){
1205
fprintf_plus(stderr, "Accepting point-to-point interface"
1206
" \"%s\"\n", ifname);
1210
/* Otherwise, reject non-broadcast-capable devices */
1211
if(not (ifr->ifr_flags & IFF_BROADCAST)){
1213
fprintf_plus(stderr, "Rejecting non-broadcast interface"
1214
" \"%s\"\n", ifname);
1218
/* Reject non-ARP interfaces (including dummy interfaces) */
1219
if(ifr->ifr_flags & IFF_NOARP){
1221
fprintf_plus(stderr, "Rejecting non-ARP interface \"%s\"\n",
1227
/* Accept this device */
1229
fprintf_plus(stderr, "Interface \"%s\" is good\n", ifname);
1235
* This function determines if a directory entry in /sys/class/net
1236
* corresponds to an acceptable network device.
1237
* (This function is passed to scandir(3) as a filter function.)
1239
int good_interface(const struct dirent *if_entry){
1240
if(if_entry->d_name[0] == '.'){
1245
if(not get_flags(if_entry->d_name, &ifr)){
1247
fprintf_plus(stderr, "Failed to get flags for interface "
1248
"\"%s\"\n", if_entry->d_name);
1253
if(not good_flags(if_entry->d_name, &ifr)){
1260
* This function determines if a network interface is up.
1262
bool interface_is_up(const char *interface){
1264
if(not get_flags(interface, &ifr)){
1266
fprintf_plus(stderr, "Failed to get flags for interface "
1267
"\"%s\"\n", interface);
1272
return (bool)(ifr.ifr_flags & IFF_UP);
1276
* This function determines if a network interface is running
1278
bool interface_is_running(const char *interface){
1280
if(not get_flags(interface, &ifr)){
1282
fprintf_plus(stderr, "Failed to get flags for interface "
1283
"\"%s\"\n", interface);
1288
return (bool)(ifr.ifr_flags & IFF_RUNNING);
1291
int notdotentries(const struct dirent *direntry){
1292
/* Skip "." and ".." */
1293
if(direntry->d_name[0] == '.'
1294
and (direntry->d_name[1] == '\0'
1295
or (direntry->d_name[1] == '.'
1296
and direntry->d_name[2] == '\0'))){
1302
/* Is this directory entry a runnable program? */
1303
int runnable_hook(const struct dirent *direntry){
1308
if((direntry->d_name)[0] == '\0'){
1313
sret = strspn(direntry->d_name, "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
1314
"abcdefghijklmnopqrstuvwxyz"
1317
if((direntry->d_name)[sret] != '\0'){
1318
/* Contains non-allowed characters */
1320
fprintf_plus(stderr, "Ignoring hook \"%s\" with bad name\n",
1326
char *fullname = NULL;
1327
ret = asprintf(&fullname, "%s/%s", hookdir, direntry->d_name);
1329
perror_plus("asprintf");
1333
ret = stat(fullname, &st);
1336
perror_plus("Could not stat hook");
1340
if(not (S_ISREG(st.st_mode))){
1341
/* Not a regular file */
1343
fprintf_plus(stderr, "Ignoring hook \"%s\" - not a file\n",
1348
if(not (st.st_mode & (S_IXUSR | S_IXGRP | S_IXOTH))){
1349
/* Not executable */
1351
fprintf_plus(stderr, "Ignoring hook \"%s\" - not executable\n",
1357
fprintf_plus(stderr, "Hook \"%s\" is acceptable\n",
1363
int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval,
1364
mandos_context *mc){
1366
struct timespec now;
1367
struct timespec waited_time;
1368
intmax_t block_time;
1371
if(mc->current_server == NULL){
1373
fprintf_plus(stderr, "Wait until first server is found."
1376
ret = avahi_simple_poll_iterate(s, -1);
1379
fprintf_plus(stderr, "Check current_server if we should run"
1382
/* the current time */
1383
ret = clock_gettime(CLOCK_MONOTONIC, &now);
1385
perror_plus("clock_gettime");
1388
/* Calculating in ms how long time between now and server
1389
who we visted longest time ago. Now - last seen. */
1390
waited_time.tv_sec = (now.tv_sec
1391
- mc->current_server->last_seen.tv_sec);
1392
waited_time.tv_nsec = (now.tv_nsec
1393
- mc->current_server->last_seen.tv_nsec);
1394
/* total time is 10s/10,000ms.
1395
Converting to s from ms by dividing by 1,000,
1396
and ns to ms by dividing by 1,000,000. */
1397
block_time = ((retry_interval
1398
- ((intmax_t)waited_time.tv_sec * 1000))
1399
- ((intmax_t)waited_time.tv_nsec / 1000000));
1402
fprintf_plus(stderr, "Blocking for %" PRIdMAX " ms\n",
1406
if(block_time <= 0){
1407
ret = start_mandos_communication(mc->current_server->ip,
1408
mc->current_server->port,
1409
mc->current_server->if_index,
1410
mc->current_server->af, mc);
1412
avahi_simple_poll_quit(s);
1415
ret = clock_gettime(CLOCK_MONOTONIC,
1416
&mc->current_server->last_seen);
1418
perror_plus("clock_gettime");
1421
mc->current_server = mc->current_server->next;
1422
block_time = 0; /* Call avahi to find new Mandos
1423
servers, but don't block */
1426
ret = avahi_simple_poll_iterate(s, (int)block_time);
1429
if (ret > 0 or errno != EINTR){
1430
return (ret != 1) ? ret : 0;
1436
/* Set effective uid to 0, return errno */
1437
error_t raise_privileges(void){
1438
error_t old_errno = errno;
1439
error_t ret_errno = 0;
1440
if(seteuid(0) == -1){
1442
perror_plus("seteuid");
1448
/* Set effective and real user ID to 0. Return errno. */
1449
error_t raise_privileges_permanently(void){
1450
error_t old_errno = errno;
1451
error_t ret_errno = raise_privileges();
1456
if(setuid(0) == -1){
1458
perror_plus("seteuid");
1464
/* Set effective user ID to unprivileged saved user ID */
1465
error_t lower_privileges(void){
1466
error_t old_errno = errno;
1467
error_t ret_errno = 0;
1468
if(seteuid(uid) == -1){
1470
perror_plus("seteuid");
1476
/* Lower privileges permanently */
1477
error_t lower_privileges_permanently(void){
1478
error_t old_errno = errno;
1479
error_t ret_errno = 0;
1480
if(setuid(uid) == -1){
1482
perror_plus("setuid");
1488
bool run_network_hooks(const char *mode, const char *interface,
1490
struct dirent **direntries;
1491
struct dirent *direntry;
1493
int numhooks = scandir(hookdir, &direntries, runnable_hook,
1496
if(errno == ENOENT){
1498
fprintf_plus(stderr, "Network hook directory \"%s\" not"
1499
" found\n", hookdir);
1502
perror_plus("scandir");
1505
int devnull = open("/dev/null", O_RDONLY);
1506
for(int i = 0; i < numhooks; i++){
1507
direntry = direntries[i];
1508
char *fullname = NULL;
1509
ret = asprintf(&fullname, "%s/%s", hookdir, direntry->d_name);
1511
perror_plus("asprintf");
1515
fprintf_plus(stderr, "Running network hook \"%s\"\n",
1518
pid_t hook_pid = fork();
1521
/* Raise privileges */
1522
raise_privileges_permanently();
1527
perror_plus("setgid");
1529
/* Reset supplementary groups */
1531
ret = setgroups(0, NULL);
1533
perror_plus("setgroups");
1535
dup2(devnull, STDIN_FILENO);
1537
dup2(STDERR_FILENO, STDOUT_FILENO);
1538
ret = setenv("MANDOSNETHOOKDIR", hookdir, 1);
1540
perror_plus("setenv");
1543
ret = setenv("DEVICE", interface, 1);
1545
perror_plus("setenv");
1548
ret = setenv("VERBOSITY", debug ? "1" : "0", 1);
1550
perror_plus("setenv");
1553
ret = setenv("MODE", mode, 1);
1555
perror_plus("setenv");
1559
ret = asprintf(&delaystring, "%f", delay);
1561
perror_plus("asprintf");
1564
ret = setenv("DELAY", delaystring, 1);
1567
perror_plus("setenv");
1571
if(connect_to != NULL){
1572
ret = setenv("CONNECT", connect_to, 1);
1574
perror_plus("setenv");
1578
if(execl(fullname, direntry->d_name, mode, NULL) == -1){
1579
perror_plus("execl");
1580
_exit(EXIT_FAILURE);
1584
if(TEMP_FAILURE_RETRY(waitpid(hook_pid, &status, 0)) == -1){
1585
perror_plus("waitpid");
1589
if(WIFEXITED(status)){
1590
if(WEXITSTATUS(status) != 0){
1591
fprintf_plus(stderr, "Warning: network hook \"%s\" exited"
1592
" with status %d\n", direntry->d_name,
1593
WEXITSTATUS(status));
1597
} else if(WIFSIGNALED(status)){
1598
fprintf_plus(stderr, "Warning: network hook \"%s\" died by"
1599
" signal %d\n", direntry->d_name,
1604
fprintf_plus(stderr, "Warning: network hook \"%s\""
1605
" crashed\n", direntry->d_name);
1612
fprintf_plus(stderr, "Network hook \"%s\" ran successfully\n",
1621
error_t bring_up_interface(const char *const interface,
1624
error_t old_errno = errno;
1625
error_t ret_errno = 0;
1626
int ret, ret_setflags;
1627
struct ifreq network;
1628
unsigned int if_index = if_nametoindex(interface);
1630
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
1640
if(not interface_is_up(interface)){
1641
if(not get_flags(interface, &network) and debug){
1643
fprintf_plus(stderr, "Failed to get flags for interface "
1644
"\"%s\"\n", interface);
1647
network.ifr_flags |= IFF_UP;
1649
sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1652
perror_plus("socket");
1664
fprintf_plus(stderr, "Bringing up interface \"%s\"\n",
1668
/* Raise priviliges */
1672
/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO
1673
messages about the network interface to mess up the prompt */
1674
int ret_linux = klogctl(8, NULL, 5);
1675
bool restore_loglevel = true;
1676
if(ret_linux == -1){
1677
restore_loglevel = false;
1678
perror_plus("klogctl");
1680
#endif /* __linux__ */
1681
ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
1684
if(restore_loglevel){
1685
ret_linux = klogctl(7, NULL, 0);
1686
if(ret_linux == -1){
1687
perror_plus("klogctl");
1690
#endif /* __linux__ */
1692
/* Lower privileges */
1695
/* Close the socket */
1696
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1698
perror_plus("close");
1701
if(ret_setflags == -1){
1703
perror_plus("ioctl SIOCSIFFLAGS +IFF_UP");
1708
fprintf_plus(stderr, "Interface \"%s\" is already up; good\n",
1712
/* Sleep checking until interface is running.
1713
Check every 0.25s, up to total time of delay */
1714
for(int i=0; i < delay * 4; i++){
1715
if(interface_is_running(interface)){
1718
struct timespec sleeptime = { .tv_nsec = 250000000 };
1719
ret = nanosleep(&sleeptime, NULL);
1720
if(ret == -1 and errno != EINTR){
1721
perror_plus("nanosleep");
1729
error_t take_down_interface(const char *const interface){
1731
error_t old_errno = errno;
1732
error_t ret_errno = 0;
1733
int ret, ret_setflags;
1734
struct ifreq network;
1735
unsigned int if_index = if_nametoindex(interface);
1737
fprintf_plus(stderr, "No such interface: \"%s\"\n", interface);
1741
if(interface_is_up(interface)){
1742
if(not get_flags(interface, &network) and debug){
1744
fprintf_plus(stderr, "Failed to get flags for interface "
1745
"\"%s\"\n", interface);
1748
network.ifr_flags &= ~(short)IFF_UP; /* clear flag */
1750
sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1753
perror_plus("socket");
1759
fprintf_plus(stderr, "Taking down interface \"%s\"\n",
1763
/* Raise priviliges */
1766
ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
1769
/* Lower privileges */
1772
/* Close the socket */
1773
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1775
perror_plus("close");
1778
if(ret_setflags == -1){
1780
perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");
1785
fprintf_plus(stderr, "Interface \"%s\" is already down; odd\n",
824
1793
int main(int argc, char *argv[]){
1794
mandos_context mc = { .server = NULL, .dh_bits = 1024,
1795
.priority = "SECURE256:!CTYPE-X.509:"
1796
"+CTYPE-OPENPGP", .current_server = NULL,
1797
.interfaces = NULL, .interfaces_size = 0 };
825
1798
AvahiSServiceBrowser *sb = NULL;
828
1801
intmax_t tmpmax;
830
1803
int exitcode = EXIT_SUCCESS;
831
const char *interface = "eth0";
832
struct ifreq network;
836
char *connect_to = NULL;
1804
char *interfaces_to_take_down = NULL;
1805
size_t interfaces_to_take_down_size = 0;
837
1806
char tempdir[] = "/tmp/mandosXXXXXX";
838
1807
bool tempdir_created = false;
839
1808
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
840
1809
const char *seckey = PATHDIR "/" SECKEY;
841
1810
const char *pubkey = PATHDIR "/" PUBKEY;
1811
char *interfaces_hooks = NULL;
1812
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
1814
bool gnutls_initialized = false;
847
1815
bool gpgme_initialized = false;
1817
double retry_interval = 10; /* 10s between trying a server and
1818
retrying the same server again */
1820
struct sigaction old_sigterm_action = { .sa_handler = SIG_DFL };
1821
struct sigaction sigterm_action = { .sa_handler = handle_sigterm };
1826
/* Lower any group privileges we might have, just to be safe */
1830
perror_plus("setgid");
1833
/* Lower user privileges (temporarily) */
1837
perror_plus("seteuid");
851
1845
struct argp_option options[] = {
915
1931
mc.priority = arg;
917
1933
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");
1935
delay = strtof(arg, &tmp);
1936
if(errno != 0 or tmp == arg or *tmp != '\0'){
1937
argp_error(state, "Bad delay");
1939
case 132: /* --retry */
1941
retry_interval = strtod(arg, &tmp);
1942
if(errno != 0 or tmp == arg or *tmp != '\0'
1943
or (retry_interval * 1000) > INT_MAX
1944
or retry_interval < 0){
1945
argp_error(state, "Bad retry interval");
1948
case 133: /* --network-hook-dir */
1952
* These reproduce what we would get without ARGP_NO_HELP
1954
case '?': /* --help */
1955
argp_state_help(state, state->out_stream,
1956
(ARGP_HELP_STD_HELP | ARGP_HELP_EXIT_ERR)
1957
& ~(unsigned int)ARGP_HELP_EXIT_OK);
1958
case -3: /* --usage */
1959
argp_state_help(state, state->out_stream,
1960
ARGP_HELP_USAGE | ARGP_HELP_EXIT_ERR);
1961
case 'V': /* --version */
1962
fprintf_plus(state->out_stream, "%s\n", argp_program_version);
1963
exit(argp_err_exit_status);
929
1966
return ARGP_ERR_UNKNOWN;
934
1971
struct argp argp = { .options = options, .parser = parse_opt,
936
1973
.doc = "Mandos client -- Get and decrypt"
937
1974
" 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);
1975
ret = argp_parse(&argp, argc, argv,
1976
ARGP_IN_ORDER | ARGP_NO_HELP, 0, NULL);
1983
perror_plus("argp_parse");
1984
exitcode = EX_OSERR;
1987
exitcode = EX_USAGE;
1993
/* Work around Debian bug #633582:
1994
<http://bugs.debian.org/633582> */
1996
/* Re-raise priviliges */
1997
if(raise_privileges() == 0){
2000
if(strcmp(seckey, PATHDIR "/" SECKEY) == 0){
2001
int seckey_fd = open(seckey, O_RDONLY);
2002
if(seckey_fd == -1){
2003
perror_plus("open");
2005
ret = (int)TEMP_FAILURE_RETRY(fstat(seckey_fd, &st));
2007
perror_plus("fstat");
2009
if(S_ISREG(st.st_mode)
2010
and st.st_uid == 0 and st.st_gid == 0){
2011
ret = fchown(seckey_fd, uid, gid);
2013
perror_plus("fchown");
2017
TEMP_FAILURE_RETRY(close(seckey_fd));
2021
if(strcmp(pubkey, PATHDIR "/" PUBKEY) == 0){
2022
int pubkey_fd = open(pubkey, O_RDONLY);
2023
if(pubkey_fd == -1){
2024
perror_plus("open");
2026
ret = (int)TEMP_FAILURE_RETRY(fstat(pubkey_fd, &st));
2028
perror_plus("fstat");
2030
if(S_ISREG(st.st_mode)
2031
and st.st_uid == 0 and st.st_gid == 0){
2032
ret = fchown(pubkey_fd, uid, gid);
2034
perror_plus("fchown");
2038
TEMP_FAILURE_RETRY(close(pubkey_fd));
2042
/* Lower privileges */
2047
/* Remove invalid interface names (except "none") */
2049
char *interface = NULL;
2050
while((interface = argz_next(mc.interfaces, mc.interfaces_size,
2052
if(strcmp(interface, "none") != 0
2053
and if_nametoindex(interface) == 0){
2054
if(interface[0] != '\0'){
2055
fprintf_plus(stderr, "Not using nonexisting interface"
2056
" \"%s\"\n", interface);
2058
argz_delete(&mc.interfaces, &mc.interfaces_size, interface);
2064
/* Run network hooks */
2066
if(mc.interfaces != NULL){
2067
interfaces_hooks = malloc(mc.interfaces_size);
2068
if(interfaces_hooks == NULL){
2069
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){
2072
memcpy(interfaces_hooks, mc.interfaces, mc.interfaces_size);
2073
interfaces_hooks_size = mc.interfaces_size;
2074
argz_stringify(interfaces_hooks, interfaces_hooks_size,
2077
if(not run_network_hooks("start", interfaces_hooks != NULL ?
2078
interfaces_hooks : "", delay)){
2084
avahi_set_log_function(empty_log);
2087
/* Initialize Avahi early so avahi_simple_poll_quit() can be called
2088
from the signal handler */
2089
/* Initialize the pseudo-RNG for Avahi */
2090
srand((unsigned int) time(NULL));
2091
simple_poll = avahi_simple_poll_new();
2092
if(simple_poll == NULL){
2093
fprintf_plus(stderr,
2094
"Avahi: Failed to create simple poll object.\n");
2095
exitcode = EX_UNAVAILABLE;
2099
sigemptyset(&sigterm_action.sa_mask);
2100
ret = sigaddset(&sigterm_action.sa_mask, SIGINT);
2102
perror_plus("sigaddset");
2103
exitcode = EX_OSERR;
2106
ret = sigaddset(&sigterm_action.sa_mask, SIGHUP);
2108
perror_plus("sigaddset");
2109
exitcode = EX_OSERR;
2112
ret = sigaddset(&sigterm_action.sa_mask, SIGTERM);
2114
perror_plus("sigaddset");
2115
exitcode = EX_OSERR;
2118
/* Need to check if the handler is SIG_IGN before handling:
2119
| [[info:libc:Initial Signal Actions]] |
2120
| [[info:libc:Basic Signal Handling]] |
2122
ret = sigaction(SIGINT, NULL, &old_sigterm_action);
2124
perror_plus("sigaction");
2127
if(old_sigterm_action.sa_handler != SIG_IGN){
2128
ret = sigaction(SIGINT, &sigterm_action, NULL);
2130
perror_plus("sigaction");
2131
exitcode = EX_OSERR;
2135
ret = sigaction(SIGHUP, NULL, &old_sigterm_action);
2137
perror_plus("sigaction");
2140
if(old_sigterm_action.sa_handler != SIG_IGN){
2141
ret = sigaction(SIGHUP, &sigterm_action, NULL);
2143
perror_plus("sigaction");
2144
exitcode = EX_OSERR;
2148
ret = sigaction(SIGTERM, NULL, &old_sigterm_action);
2150
perror_plus("sigaction");
2153
if(old_sigterm_action.sa_handler != SIG_IGN){
2154
ret = sigaction(SIGTERM, &sigterm_action, NULL);
2156
perror_plus("sigaction");
2157
exitcode = EX_OSERR;
2162
/* If no interfaces were specified, make a list */
2163
if(mc.interfaces == NULL){
2164
struct dirent **direntries;
2165
/* Look for any good interfaces */
2166
ret = scandir(sys_class_net, &direntries, good_interface,
2169
/* Add all found interfaces to interfaces list */
2170
for(int i = 0; i < ret; ++i){
2171
ret_errno = argz_add(&mc.interfaces, &mc.interfaces_size,
2172
direntries[i]->d_name);
2174
perror_plus("argz_add");
2178
fprintf_plus(stderr, "Will use interface \"%s\"\n",
2179
direntries[i]->d_name);
2185
fprintf_plus(stderr, "Could not find a network interface\n");
2186
exitcode = EXIT_FAILURE;
2191
/* Bring up interfaces which are down, and remove any "none"s */
2193
char *interface = NULL;
2194
while((interface = argz_next(mc.interfaces, mc.interfaces_size,
2196
/* If interface name is "none", stop bringing up interfaces.
2197
Also remove all instances of "none" from the list */
2198
if(strcmp(interface, "none") == 0){
2199
argz_delete(&mc.interfaces, &mc.interfaces_size,
2202
while((interface = argz_next(mc.interfaces,
2203
mc.interfaces_size, interface))){
2204
if(strcmp(interface, "none") == 0){
2205
argz_delete(&mc.interfaces, &mc.interfaces_size,
1005
struct timespec sleeptime = { .tv_nsec = 250000000 };
1006
ret = nanosleep(&sleeptime, NULL);
1007
if(ret == -1 and errno != EINTR){
1008
perror("nanosleep");
2212
bool interface_was_up = interface_is_up(interface);
2213
ret = bring_up_interface(interface, delay);
2214
if(not interface_was_up){
2217
perror_plus("Failed to bring up interface");
2219
ret_errno = argz_add(&interfaces_to_take_down,
2220
&interfaces_to_take_down_size,
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;
2225
if(debug and (interfaces_to_take_down == NULL)){
2226
fprintf_plus(stderr, "No interfaces were brought up\n");
2230
/* If we only got one interface, explicitly use only that one */
2231
if(argz_count(mc.interfaces, mc.interfaces_size) == 1){
2233
fprintf_plus(stderr, "Using only interface \"%s\"\n",
2236
if_index = (AvahiIfIndex)if_nametoindex(mc.interfaces);
2243
ret = init_gnutls_global(pubkey, seckey, &mc);
2245
fprintf_plus(stderr, "init_gnutls_global failed\n");
2246
exitcode = EX_UNAVAILABLE;
1043
2249
gnutls_initialized = true;
1046
2256
if(mkdtemp(tempdir) == NULL){
2257
perror_plus("mkdtemp");
1050
2260
tempdir_created = true;
1052
if(not init_gpgme(&mc, pubkey, seckey, tempdir)){
1053
fprintf(stderr, "init_gpgme failed\n");
1054
exitcode = EXIT_FAILURE;
2266
if(not init_gpgme(pubkey, seckey, tempdir, &mc)){
2267
fprintf_plus(stderr, "init_gpgme failed\n");
2268
exitcode = EX_UNAVAILABLE;
1057
2271
gpgme_initialized = true;
1060
if_index = (AvahiIfIndex) if_nametoindex(interface);
1062
fprintf(stderr, "No such interface: \"%s\"\n", interface);
1063
exitcode = EXIT_FAILURE;