56
56
#include <sys/stat.h> /* open(), S_ISREG */
57
57
#include <sys/socket.h> /* socket(), struct sockaddr_in6,
58
inet_pton(), connect(),
58
inet_pton(), connect() */
60
59
#include <fcntl.h> /* open() */
61
60
#include <dirent.h> /* opendir(), struct dirent, readdir()
74
73
#include <unistd.h> /* close(), SEEK_SET, off_t, write(),
75
74
getuid(), getgid(), seteuid(),
76
75
setgid(), pause(), _exit() */
77
#include <arpa/inet.h> /* inet_pton(), htons() */
76
#include <arpa/inet.h> /* inet_pton(), htons, inet_ntop() */
78
77
#include <iso646.h> /* not, or, and */
79
78
#include <argp.h> /* struct argp_option, error_t, struct
80
79
argp_state, struct argp,
92
91
argz_delete(), argz_append(),
93
92
argz_stringify(), argz_add(),
95
#include <netdb.h> /* getnameinfo(), NI_NUMERICHOST,
96
EAI_SYSTEM, gai_strerror() */
99
96
#include <sys/klog.h> /* klogctl() */
137
134
bool debug = false;
138
135
static const char mandos_protocol_version[] = "1";
139
const char * argp_program_version = "mandos-client " VERSION;
140
const char * argp_program_bug_address = "<mandos@recompile.se>";
136
const char *argp_program_version = "mandos-client " VERSION;
137
const char *argp_program_bug_address = "<mandos@recompile.se>";
141
138
static const char sys_class_net[] = "/sys/class/net";
142
139
char *connect_to = NULL;
143
140
const char *hookdir = HOOKDIR;
183
180
perror(print_text);
186
__attribute__((format (gnu_printf, 2, 3), nonnull))
183
__attribute__((format (gnu_printf, 2, 3)))
187
184
int fprintf_plus(FILE *stream, const char *format, ...){
189
186
va_start (ap, format);
198
195
* bytes. "buffer_capacity" is how much is currently allocated,
199
196
* "buffer_length" is how much is already used.
201
__attribute__((nonnull, warn_unused_result))
202
198
size_t incbuffer(char **buffer, size_t buffer_length,
203
199
size_t buffer_capacity){
204
200
if(buffer_length + BUFFER_SIZE > buffer_capacity){
205
char *new_buf = realloc(*buffer, buffer_capacity + BUFFER_SIZE);
207
int old_errno = errno;
201
*buffer = realloc(*buffer, buffer_capacity + BUFFER_SIZE);
214
205
buffer_capacity += BUFFER_SIZE;
216
207
return buffer_capacity;
219
210
/* Add server to set of servers to retry periodically */
220
__attribute__((nonnull, warn_unused_result))
221
211
bool add_server(const char *ip, in_port_t port, AvahiIfIndex if_index,
222
212
int af, server **current_server){
234
224
perror_plus("strdup");
237
ret = clock_gettime(CLOCK_MONOTONIC, &(new_server->last_seen));
239
perror_plus("clock_gettime");
242
227
/* Special case of first server */
243
228
if(*current_server == NULL){
244
229
new_server->next = new_server;
245
230
new_server->prev = new_server;
246
231
*current_server = new_server;
232
/* Place the new server last in the list */
248
/* Place the new server last in the list */
249
234
new_server->next = *current_server;
250
235
new_server->prev = (*current_server)->prev;
251
236
new_server->prev->next = new_server;
252
237
(*current_server)->prev = new_server;
239
ret = clock_gettime(CLOCK_MONOTONIC, &(*current_server)->last_seen);
241
perror_plus("clock_gettime");
258
248
* Initialize GPGME.
260
__attribute__((nonnull, warn_unused_result))
261
static bool init_gpgme(const char * const seckey,
262
const char * const pubkey,
263
const char * const tempdir,
250
static bool init_gpgme(const char *seckey, const char *pubkey,
251
const char *tempdir, mandos_context *mc){
265
252
gpgme_error_t rc;
266
253
gpgme_engine_info_t engine_info;
269
256
* Helper function to insert pub and seckey to the engine keyring.
271
bool import_key(const char * const filename){
258
bool import_key(const char *filename){
274
261
gpgme_data_t pgp_data;
492
477
/* GnuTLS log function callback */
493
__attribute__((nonnull))
494
478
static void debuggnutls(__attribute__((unused)) int level,
495
479
const char* string){
496
480
fprintf_plus(stderr, "GnuTLS: %s", string);
499
__attribute__((nonnull, warn_unused_result))
500
483
static int init_gnutls_global(const char *pubkeyfilename,
501
484
const char *seckeyfilename,
502
485
mandos_context *mc){
639
621
__attribute__((unused)) const char *txt){}
641
623
/* Called when a Mandos server is found */
642
__attribute__((nonnull, warn_unused_result))
643
624
static int start_mandos_communication(const char *ip, in_port_t port,
644
625
AvahiIfIndex if_index,
645
626
int af, mandos_context *mc){
646
627
int ret, tcp_sd = -1;
648
struct sockaddr_storage to;
630
struct sockaddr_in in;
631
struct sockaddr_in6 in6;
649
633
char *buffer = NULL;
650
634
char *decrypted_buffer = NULL;
651
635
size_t buffer_length = 0;
733
717
memset(&to, 0, sizeof(to));
734
718
if(af == AF_INET6){
735
((struct sockaddr_in6 *)&to)->sin6_family = (sa_family_t)af;
736
ret = inet_pton(af, ip, &((struct sockaddr_in6 *)&to)->sin6_addr);
719
to.in6.sin6_family = (sa_family_t)af;
720
ret = inet_pton(af, ip, &to.in6.sin6_addr);
737
721
} else { /* IPv4 */
738
((struct sockaddr_in *)&to)->sin_family = (sa_family_t)af;
739
ret = inet_pton(af, ip, &((struct sockaddr_in *)&to)->sin_addr);
722
to.in.sin_family = (sa_family_t)af;
723
ret = inet_pton(af, ip, &to.in.sin_addr);
753
737
if(af == AF_INET6){
754
((struct sockaddr_in6 *)&to)->sin6_port = htons(port);
755
if(IN6_IS_ADDR_LINKLOCAL
756
(&((struct sockaddr_in6 *)&to)->sin6_addr)){
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
757
748
if(if_index == AVAHI_IF_UNSPEC){
758
749
fprintf_plus(stderr, "An IPv6 link-local address is"
759
750
" incomplete without a network interface\n");
763
754
/* Set the network interface number as scope */
764
((struct sockaddr_in6 *)&to)->sin6_scope_id = (uint32_t)if_index;
755
to.in6.sin6_scope_id = (uint32_t)if_index;
767
((struct sockaddr_in *)&to)->sin_port = htons(port);
758
to.in.sin_port = htons(port);
788
779
char addrstr[(INET_ADDRSTRLEN > INET6_ADDRSTRLEN) ?
789
780
INET_ADDRSTRLEN : INET6_ADDRSTRLEN] = "";
790
782
if(af == AF_INET6){
791
ret = getnameinfo((struct sockaddr *)&to,
792
sizeof(struct sockaddr_in6),
793
addrstr, sizeof(addrstr), NULL, 0,
783
pcret = inet_ntop(af, &(to.in6.sin6_addr), addrstr,
796
ret = getnameinfo((struct sockaddr *)&to,
797
sizeof(struct sockaddr_in),
798
addrstr, sizeof(addrstr), NULL, 0,
786
pcret = inet_ntop(af, &(to.in.sin_addr), addrstr,
801
if(ret == EAI_SYSTEM){
802
perror_plus("getnameinfo");
803
} else if(ret != 0) {
804
fprintf_plus(stderr, "getnameinfo: %s", gai_strerror(ret));
805
} else if(strcmp(addrstr, ip) != 0){
806
fprintf_plus(stderr, "Canonical address form: %s\n", addrstr);
790
perror_plus("inet_ntop");
792
if(strcmp(addrstr, ip) != 0){
793
fprintf_plus(stderr, "Canonical address form: %s\n", addrstr);
815
803
if(af == AF_INET6){
816
ret = connect(tcp_sd, (struct sockaddr *)&to,
817
sizeof(struct sockaddr_in6));
804
ret = connect(tcp_sd, &to.in6, sizeof(to));
819
ret = connect(tcp_sd, (struct sockaddr *)&to, /* IPv4 */
820
sizeof(struct sockaddr_in));
806
ret = connect(tcp_sd, &to.in, sizeof(to)); /* IPv4 */
823
if((errno != ECONNREFUSED and errno != ENETUNREACH) or debug){
809
if ((errno != ECONNREFUSED and errno != ENETUNREACH) or debug){
825
811
perror_plus("connect");
1253
1236
* corresponds to an acceptable network device.
1254
1237
* (This function is passed to scandir(3) as a filter function.)
1256
__attribute__((nonnull, warn_unused_result))
1257
1239
int good_interface(const struct dirent *if_entry){
1258
1240
if(if_entry->d_name[0] == '.'){
1278
1260
* This function determines if a network interface is up.
1280
__attribute__((nonnull, warn_unused_result))
1281
1262
bool interface_is_up(const char *interface){
1282
1263
struct ifreq ifr;
1283
1264
if(not get_flags(interface, &ifr)){
1295
1276
* This function determines if a network interface is running
1297
__attribute__((nonnull, warn_unused_result))
1298
1278
bool interface_is_running(const char *interface){
1299
1279
struct ifreq ifr;
1300
1280
if(not get_flags(interface, &ifr)){
1308
1288
return (bool)(ifr.ifr_flags & IFF_RUNNING);
1311
__attribute__((nonnull, pure, warn_unused_result))
1312
1291
int notdotentries(const struct dirent *direntry){
1313
1292
/* Skip "." and ".." */
1314
1293
if(direntry->d_name[0] == '.'
1394
1371
if(mc->current_server == NULL){
1396
1373
fprintf_plus(stderr, "Wait until first server is found."
1397
1374
" No timeout!\n");
1399
1376
ret = avahi_simple_poll_iterate(s, -1);
1402
1379
fprintf_plus(stderr, "Check current_server if we should run"
1403
1380
" it, or wait\n");
1449
1426
ret = avahi_simple_poll_iterate(s, (int)block_time);
1452
if(ret > 0 or errno != EINTR){
1429
if (ret > 0 or errno != EINTR){
1453
1430
return (ret != 1) ? ret : 0;
1459
1436
/* Set effective uid to 0, return errno */
1460
__attribute__((warn_unused_result))
1461
1437
error_t raise_privileges(void){
1462
1438
error_t old_errno = errno;
1463
1439
error_t ret_errno = 0;
1472
1448
/* Set effective and real user ID to 0. Return errno. */
1473
__attribute__((warn_unused_result))
1474
1449
error_t raise_privileges_permanently(void){
1475
1450
error_t old_errno = errno;
1476
1451
error_t ret_errno = raise_privileges();
1512
1485
return ret_errno;
1515
__attribute__((nonnull))
1516
void run_network_hooks(const char *mode, const char *interface,
1488
bool run_network_hooks(const char *mode, const char *interface,
1517
1489
const float delay){
1518
1490
struct dirent **direntries;
1491
struct dirent *direntry;
1519
1493
int numhooks = scandir(hookdir, &direntries, runnable_hook,
1521
1495
if(numhooks == -1){
1547
1519
if(hook_pid == 0){
1549
1521
/* Raise privileges */
1550
if(raise_privileges_permanently() != 0){
1551
perror_plus("Failed to raise privileges");
1522
raise_privileges_permanently();
1554
1523
/* Set group */
1556
1525
ret = setgid(0);
1558
1527
perror_plus("setgid");
1561
1529
/* Reset supplementary groups */
1563
1531
ret = setgroups(0, NULL);
1565
1533
perror_plus("setgroups");
1568
ret = dup2(devnull, STDIN_FILENO);
1570
perror_plus("dup2(devnull, STDIN_FILENO)");
1573
ret = close(devnull);
1575
perror_plus("close");
1578
ret = dup2(STDERR_FILENO, STDOUT_FILENO);
1580
perror_plus("dup2(STDERR_FILENO, STDOUT_FILENO)");
1535
dup2(devnull, STDIN_FILENO);
1537
dup2(STDERR_FILENO, STDOUT_FILENO);
1583
1538
ret = setenv("MANDOSNETHOOKDIR", hookdir, 1);
1585
1540
perror_plus("setenv");
1661
1616
close(devnull);
1665
__attribute__((nonnull, warn_unused_result))
1666
1621
error_t bring_up_interface(const char *const interface,
1667
1622
const float delay){
1668
1624
error_t old_errno = errno;
1625
error_t ret_errno = 0;
1626
int ret, ret_setflags;
1670
1627
struct ifreq network;
1671
1628
unsigned int if_index = if_nametoindex(interface);
1672
1629
if(if_index == 0){
1683
1640
if(not interface_is_up(interface)){
1684
error_t ret_errno = 0, ioctl_errno = 0;
1685
if(not get_flags(interface, &network)){
1641
if(not get_flags(interface, &network) and debug){
1686
1642
ret_errno = errno;
1687
1643
fprintf_plus(stderr, "Failed to get flags for interface "
1688
1644
"\"%s\"\n", interface);
1690
1645
return ret_errno;
1692
network.ifr_flags |= IFF_UP; /* set flag */
1647
network.ifr_flags |= IFF_UP;
1694
int sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1649
sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1696
1651
ret_errno = errno;
1697
1652
perror_plus("socket");
1698
1653
errno = old_errno;
1699
1654
return ret_errno;
1703
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1705
perror_plus("close");
1707
1659
errno = old_errno;
1716
/* Raise privileges */
1717
ret_errno = raise_privileges();
1718
bool restore_loglevel = false;
1720
perror_plus("Failed to raise privileges");
1668
/* Raise priviliges */
1722
1671
#ifdef __linux__
1725
/* Lower kernel loglevel to KERN_NOTICE to avoid KERN_INFO
1726
messages about the network interface to mess up the prompt */
1727
ret_linux = klogctl(8, NULL, 5);
1728
if(ret_linux == -1){
1729
perror_plus("klogctl");
1731
restore_loglevel = true;
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");
1734
1680
#endif /* __linux__ */
1735
int ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
1736
ioctl_errno = errno;
1681
ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
1737
1683
#ifdef __linux__
1738
1684
if(restore_loglevel){
1739
1685
ret_linux = klogctl(7, NULL, 0);
1790
__attribute__((nonnull, warn_unused_result))
1791
1729
error_t take_down_interface(const char *const interface){
1792
1731
error_t old_errno = errno;
1732
error_t ret_errno = 0;
1733
int ret, ret_setflags;
1793
1734
struct ifreq network;
1794
1735
unsigned int if_index = if_nametoindex(interface);
1795
1736
if(if_index == 0){
1800
1741
if(interface_is_up(interface)){
1801
error_t ret_errno = 0, ioctl_errno = 0;
1802
1742
if(not get_flags(interface, &network) and debug){
1803
1743
ret_errno = errno;
1804
1744
fprintf_plus(stderr, "Failed to get flags for interface "
1805
1745
"\"%s\"\n", interface);
1807
1746
return ret_errno;
1809
1748
network.ifr_flags &= ~(short)IFF_UP; /* clear flag */
1811
int sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1750
sd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1813
1752
ret_errno = errno;
1814
1753
perror_plus("socket");
1815
1754
errno = old_errno;
1824
/* Raise privileges */
1825
ret_errno = raise_privileges();
1827
perror_plus("Failed to raise privileges");
1829
int ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
1830
ioctl_errno = errno;
1832
/* If raise_privileges() succeeded above */
1834
/* Lower privileges */
1835
ret_errno = lower_privileges();
1838
perror_plus("Failed to lower privileges");
1763
/* Raise priviliges */
1766
ret_setflags = ioctl(sd, SIOCSIFFLAGS, &network);
1769
/* Lower privileges */
1842
1772
/* Close the socket */
1843
int ret = (int)TEMP_FAILURE_RETRY(close(sd));
1773
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1845
1775
perror_plus("close");
1848
1778
if(ret_setflags == -1){
1849
errno = ioctl_errno;
1850
1780
perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");
1851
1781
errno = old_errno;
1854
1784
} else if(debug){
1855
1785
fprintf_plus(stderr, "Interface \"%s\" is already down; odd\n",
1863
1793
int main(int argc, char *argv[]){
1864
1794
mandos_context mc = { .server = NULL, .dh_bits = 1024,
1865
1795
.priority = "SECURE256:!CTYPE-X.509:"
1866
"+CTYPE-OPENPGP", .current_server = NULL,
1796
"+CTYPE-OPENPGP", .current_server = NULL,
1867
1797
.interfaces = NULL, .interfaces_size = 0 };
1868
1798
AvahiSServiceBrowser *sb = NULL;
1869
1799
error_t ret_errno;
1873
1803
int exitcode = EXIT_SUCCESS;
1874
1804
char *interfaces_to_take_down = NULL;
1875
1805
size_t interfaces_to_take_down_size = 0;
1876
char run_tempdir[] = "/run/tmp/mandosXXXXXX";
1877
char old_tempdir[] = "/tmp/mandosXXXXXX";
1878
char *tempdir = NULL;
1806
char tempdir[] = "/tmp/mandosXXXXXX";
1807
bool tempdir_created = false;
1879
1808
AvahiIfIndex if_index = AVAHI_IF_UNSPEC;
1880
1809
const char *seckey = PATHDIR "/" SECKEY;
1881
1810
const char *pubkey = PATHDIR "/" PUBKEY;
1882
1811
char *interfaces_hooks = NULL;
1812
size_t interfaces_hooks_size = 0;
1884
1814
bool gnutls_initialized = false;
1885
1815
bool gpgme_initialized = false;
2063
1993
/* Work around Debian bug #633582:
2064
1994
<http://bugs.debian.org/633582> */
2066
/* Re-raise privileges */
2067
ret_errno = raise_privileges();
2070
perror_plus("Failed to raise privileges");
1996
/* Re-raise priviliges */
1997
if(raise_privileges() == 0){
2072
1998
struct stat st;
2074
2000
if(strcmp(seckey, PATHDIR "/" SECKEY) == 0){
2150
2072
memcpy(interfaces_hooks, mc.interfaces, mc.interfaces_size);
2151
argz_stringify(interfaces_hooks, mc.interfaces_size, (int)',');
2153
run_network_hooks("start", interfaces_hooks != NULL ?
2154
interfaces_hooks : "", delay);
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)){
2287
2212
bool interface_was_up = interface_is_up(interface);
2288
errno = bring_up_interface(interface, delay);
2213
ret = bring_up_interface(interface, delay);
2289
2214
if(not interface_was_up){
2291
2217
perror_plus("Failed to bring up interface");
2293
errno = argz_add(&interfaces_to_take_down,
2294
&interfaces_to_take_down_size,
2297
perror_plus("argz_add");
2219
ret_errno = argz_add(&interfaces_to_take_down,
2220
&interfaces_to_take_down_size,
2333
/* Try /run/tmp before /tmp */
2334
tempdir = mkdtemp(run_tempdir);
2335
if(tempdir == NULL and errno == ENOENT){
2337
fprintf_plus(stderr, "Tempdir %s did not work, trying %s\n",
2338
run_tempdir, old_tempdir);
2340
tempdir = mkdtemp(old_tempdir);
2342
if(tempdir == NULL){
2256
if(mkdtemp(tempdir) == NULL){
2343
2257
perror_plus("mkdtemp");
2260
tempdir_created = true;
2534
/* Re-raise privileges */
2449
/* Re-raise priviliges */
2536
ret_errno = raise_privileges();
2538
perror_plus("Failed to raise privileges");
2541
/* Run network hooks */
2542
run_network_hooks("stop", interfaces_hooks != NULL ?
2543
interfaces_hooks : "", delay);
2545
/* Take down the network interfaces which were brought up */
2547
char *interface = NULL;
2548
while((interface=argz_next(interfaces_to_take_down,
2549
interfaces_to_take_down_size,
2551
ret_errno = take_down_interface(interface);
2554
perror_plus("Failed to take down interface");
2557
if(debug and (interfaces_to_take_down == NULL)){
2558
fprintf_plus(stderr, "No interfaces needed to be taken"
2563
ret_errno = lower_privileges_permanently();
2565
perror_plus("Failed to lower privileges permanently");
2453
/* Run network hooks */
2454
run_network_hooks("stop", interfaces_hooks != NULL ?
2455
interfaces_hooks : "", delay);
2457
/* Take down the network interfaces which were brought up */
2459
char *interface = NULL;
2460
while((interface=argz_next(interfaces_to_take_down,
2461
interfaces_to_take_down_size,
2463
ret_errno = take_down_interface(interface);
2466
perror_plus("Failed to take down interface");
2469
if(debug and (interfaces_to_take_down == NULL)){
2470
fprintf_plus(stderr, "No interfaces needed to be taken"
2475
lower_privileges_permanently();
2569
2478
free(interfaces_to_take_down);
2570
2479
free(interfaces_hooks);
2572
2481
/* Removes the GPGME temp directory and all files inside */
2573
if(tempdir != NULL){
2482
if(tempdir_created){
2574
2483
struct dirent **direntries = NULL;
2575
2484
struct dirent *direntry = NULL;
2576
2485
int numentries = scandir(tempdir, &direntries, notdotentries,
2487
if (numentries > 0){
2579
2488
for(int i = 0; i < numentries; i++){
2580
2489
direntry = direntries[i];
2581
2490
char *fullname = NULL;