62
62
#include <inttypes.h> /* PRIu16, PRIdMAX, intmax_t,
64
64
#include <assert.h> /* assert() */
65
#include <errno.h> /* perror(), errno,
66
program_invocation_short_name */
65
#include <errno.h> /* perror(), errno */
67
66
#include <time.h> /* nanosleep(), time(), sleep() */
68
67
#include <net/if.h> /* ioctl, ifreq, SIOCGIFFLAGS, IFF_UP,
69
68
SIOCSIFFLAGS, if_indextoname(),
74
73
#include <unistd.h> /* close(), SEEK_SET, off_t, write(),
75
74
getuid(), getgid(), seteuid(),
76
75
setgid(), pause() */
77
#include <arpa/inet.h> /* inet_pton(), htons, inet_ntop() */
76
#include <arpa/inet.h> /* inet_pton(), htons */
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,
123
122
#define PATHDIR "/conf/conf.d/mandos"
124
123
#define SECKEY "seckey.txt"
125
124
#define PUBKEY "pubkey.txt"
126
#define HOOKDIR "/lib/mandos/network-hooks.d"
128
126
bool debug = false;
129
127
static const char mandos_protocol_version[] = "1";
130
128
const char *argp_program_version = "mandos-client " VERSION;
131
const char *argp_program_bug_address = "<mandos@recompile.se>";
129
const char *argp_program_bug_address = "<mandos@fukt.bsnet.se>";
132
130
static const char sys_class_net[] = "/sys/class/net";
133
131
char *connect_to = NULL;
135
/* Doubly linked list that need to be circularly linked when used */
136
typedef struct server{
139
AvahiIfIndex if_index;
141
struct timespec last_seen;
146
133
/* Used for passing in values through the Avahi callback functions */
148
135
AvahiSimplePoll *simple_poll;
152
139
gnutls_dh_params_t dh_params;
153
140
const char *priority;
155
server *current_server;
156
142
} mandos_context;
158
144
/* global context so signal handler can reach it*/
159
145
mandos_context mc = { .simple_poll = NULL, .server = NULL,
160
146
.dh_bits = 1024, .priority = "SECURE256"
161
":!CTYPE-X.509:+CTYPE-OPENPGP",
162
.current_server = NULL };
147
":!CTYPE-X.509:+CTYPE-OPENPGP" };
164
149
sig_atomic_t quit_now = 0;
165
150
int signal_received = 0;
167
/* Function to use when printing errors */
168
void perror_plus(const char *print_text){
169
fprintf(stderr, "Mandos plugin %s: ",
170
program_invocation_short_name);
174
int fprintf_plus(FILE *stream, const char *format, ...){
176
va_start (ap, format);
178
TEMP_FAILURE_RETRY(fprintf(stream, "Mandos plugin %s: ", program_invocation_short_name));
179
return TEMP_FAILURE_RETRY(vfprintf(stream, format, ap));
183
153
* Make additional room in "buffer" for at least BUFFER_SIZE more
184
154
* bytes. "buffer_capacity" is how much is currently allocated,
196
166
return buffer_capacity;
199
/* Add server to set of servers to retry periodically */
200
int add_server(const char *ip, uint16_t port,
201
AvahiIfIndex if_index,
204
server *new_server = malloc(sizeof(server));
205
if(new_server == NULL){
206
perror_plus("malloc");
209
*new_server = (server){ .ip = strdup(ip),
211
.if_index = if_index,
213
if(new_server->ip == NULL){
214
perror_plus("strdup");
217
/* Special case of first server */
218
if (mc.current_server == NULL){
219
new_server->next = new_server;
220
new_server->prev = new_server;
221
mc.current_server = new_server;
222
/* Place the new server last in the list */
224
new_server->next = mc.current_server;
225
new_server->prev = mc.current_server->prev;
226
new_server->prev->next = new_server;
227
mc.current_server->prev = new_server;
229
ret = clock_gettime(CLOCK_MONOTONIC, &mc.current_server->last_seen);
231
perror_plus("clock_gettime");
238
170
* Initialize GPGME.
493
425
/* OpenPGP credentials */
494
ret = gnutls_certificate_allocate_credentials(&mc.cred);
426
gnutls_certificate_allocate_credentials(&mc.cred);
495
427
if(ret != GNUTLS_E_SUCCESS){
496
fprintf(stderr, "GnuTLS memory error: %s\n",
428
fprintf(stderr, "GnuTLS memory error: %s\n", /* Spurious warning
497
432
safer_gnutls_strerror(ret));
498
433
gnutls_global_deinit();
1088
1019
signal_received = sig;
1089
1020
int old_errno = errno;
1090
/* set main loop to exit */
1091
1021
if(mc.simple_poll != NULL){
1092
1022
avahi_simple_poll_quit(mc.simple_poll);
1094
1024
errno = old_errno;
1097
bool get_flags(const char *ifname, struct ifreq *ifr){
1100
int s = socket(PF_INET6, SOCK_DGRAM, IPPROTO_IP);
1102
perror_plus("socket");
1105
strcpy(ifr->ifr_name, ifname);
1106
ret = ioctl(s, SIOCGIFFLAGS, ifr);
1109
perror_plus("ioctl SIOCGIFFLAGS");
1116
bool good_flags(const char *ifname, const struct ifreq *ifr){
1118
/* Reject the loopback device */
1119
if(ifr->ifr_flags & IFF_LOOPBACK){
1121
fprintf(stderr, "Rejecting loopback interface \"%s\"\n",
1126
/* Accept point-to-point devices only if connect_to is specified */
1127
if(connect_to != NULL and (ifr->ifr_flags & IFF_POINTOPOINT)){
1129
fprintf(stderr, "Accepting point-to-point interface \"%s\"\n",
1134
/* Otherwise, reject non-broadcast-capable devices */
1135
if(not (ifr->ifr_flags & IFF_BROADCAST)){
1137
fprintf(stderr, "Rejecting non-broadcast interface \"%s\"\n",
1142
/* Reject non-ARP interfaces (including dummy interfaces) */
1143
if(ifr->ifr_flags & IFF_NOARP){
1145
fprintf(stderr, "Rejecting non-ARP interface \"%s\"\n", ifname);
1150
/* Accept this device */
1152
fprintf(stderr, "Interface \"%s\" is good\n", ifname);
1158
1028
* This function determines if a directory entry in /sys/class/net
1159
1029
* corresponds to an acceptable network device.
1160
1030
* (This function is passed to scandir(3) as a filter function.)
1162
1032
int good_interface(const struct dirent *if_entry){
1164
if(if_entry->d_name[0] == '.'){
1169
if(not get_flags(if_entry->d_name, &ifr)){
1173
if(not good_flags(if_entry->d_name, &ifr)){
1180
* This function determines if a directory entry in /sys/class/net
1181
* corresponds to an acceptable network device which is up.
1182
* (This function is passed to scandir(3) as a filter function.)
1184
int up_interface(const struct dirent *if_entry){
1186
1034
char *flagname = NULL;
1187
if(if_entry->d_name[0] == '.'){
1190
1035
int ret = asprintf(&flagname, "%s/%s/flags", sys_class_net,
1191
1036
if_entry->d_name);
1193
perror_plus("asprintf");
1041
if(if_entry->d_name[0] == '.'){
1196
1044
int flags_fd = (int)TEMP_FAILURE_RETRY(open(flagname, O_RDONLY));
1197
1045
if(flags_fd == -1){
1198
perror_plus("open");
1203
1049
typedef short ifreq_flags; /* ifreq.ifr_flags in netdevice(7) */
1204
1050
/* read line from flags_fd */
1205
ssize_t to_read = 2+(sizeof(ifreq_flags)*2)+1; /* "0x1003\n" */
1051
ssize_t to_read = (sizeof(ifreq_flags)*2)+3; /* "0x1003\n" */
1206
1052
char *flagstring = malloc((size_t)to_read+1); /* +1 for final \0 */
1207
1053
flagstring[(size_t)to_read] = '\0';
1208
1054
if(flagstring == NULL){
1209
perror_plus("malloc");
1210
1056
close(flags_fd);
1290
int notdotentries(const struct dirent *direntry){
1291
/* Skip "." and ".." */
1292
if(direntry->d_name[0] == '.'
1293
and (direntry->d_name[1] == '\0'
1294
or (direntry->d_name[1] == '.'
1295
and direntry->d_name[2] == '\0'))){
1301
/* Is this directory entry a runnable program? */
1302
int runnable_hook(const struct dirent *direntry){
1306
if((direntry->d_name)[0] == '\0'){
1311
/* Save pointer to last character */
1312
char *end = strchr(direntry->d_name, '\0')-1;
1319
if(((direntry->d_name)[0] == '#')
1321
/* Temporary #name# */
1325
/* XXX more rules here */
1327
ret = stat(direntry->d_name, &st);
1330
perror_plus("Could not stat plugin");
1334
if(not (st.st_mode & S_ISREG)){
1335
/* Not a regular file */
1338
if(not (st.st_mode & (S_IXUSR | S_IXGRP | S_IXOTH))){
1339
/* Not executable */
1345
int avahi_loop_with_timeout(AvahiSimplePoll *s, int retry_interval){
1347
struct timespec now;
1348
struct timespec waited_time;
1349
intmax_t block_time;
1352
if(mc.current_server == NULL){
1355
"Wait until first server is found. No timeout!\n");
1357
ret = avahi_simple_poll_iterate(s, -1);
1360
fprintf(stderr, "Check current_server if we should run it,"
1363
/* the current time */
1364
ret = clock_gettime(CLOCK_MONOTONIC, &now);
1366
perror_plus("clock_gettime");
1369
/* Calculating in ms how long time between now and server
1370
who we visted longest time ago. Now - last seen. */
1371
waited_time.tv_sec = (now.tv_sec
1372
- mc.current_server->last_seen.tv_sec);
1373
waited_time.tv_nsec = (now.tv_nsec
1374
- mc.current_server->last_seen.tv_nsec);
1375
/* total time is 10s/10,000ms.
1376
Converting to s from ms by dividing by 1,000,
1377
and ns to ms by dividing by 1,000,000. */
1378
block_time = ((retry_interval
1379
- ((intmax_t)waited_time.tv_sec * 1000))
1380
- ((intmax_t)waited_time.tv_nsec / 1000000));
1383
fprintf(stderr, "Blocking for %" PRIdMAX " ms\n", block_time);
1386
if(block_time <= 0){
1387
ret = start_mandos_communication(mc.current_server->ip,
1388
mc.current_server->port,
1389
mc.current_server->if_index,
1390
mc.current_server->af);
1392
avahi_simple_poll_quit(mc.simple_poll);
1395
ret = clock_gettime(CLOCK_MONOTONIC,
1396
&mc.current_server->last_seen);
1398
perror_plus("clock_gettime");
1401
mc.current_server = mc.current_server->next;
1402
block_time = 0; /* Call avahi to find new Mandos
1403
servers, but don't block */
1406
ret = avahi_simple_poll_iterate(s, (int)block_time);
1409
if (ret > 0 or errno != EINTR) {
1410
return (ret != 1) ? ret : 0;
1416
1122
int main(int argc, char *argv[]){
1417
1123
AvahiSServiceBrowser *sb = NULL;
1603
/* Work around Debian bug #633582:
1604
<http://bugs.debian.org/633582> */
1607
/* Re-raise priviliges */
1611
perror_plus("seteuid");
1614
if(strcmp(seckey, PATHDIR "/" SECKEY) == 0){
1615
int seckey_fd = open(seckey, O_RDONLY);
1616
if(seckey_fd == -1){
1617
perror_plus("open");
1619
ret = (int)TEMP_FAILURE_RETRY(fstat(seckey_fd, &st));
1621
perror_plus("fstat");
1623
if(S_ISREG(st.st_mode) and st.st_uid == 0 and st.st_gid == 0){
1624
ret = fchown(seckey_fd, uid, gid);
1626
perror_plus("fchown");
1630
TEMP_FAILURE_RETRY(close(seckey_fd));
1634
if(strcmp(pubkey, PATHDIR "/" PUBKEY) == 0){
1635
int pubkey_fd = open(pubkey, O_RDONLY);
1636
if(pubkey_fd == -1){
1637
perror_plus("open");
1639
ret = (int)TEMP_FAILURE_RETRY(fstat(pubkey_fd, &st));
1641
perror_plus("fstat");
1643
if(S_ISREG(st.st_mode) and st.st_uid == 0 and st.st_gid == 0){
1644
ret = fchown(pubkey_fd, uid, gid);
1646
perror_plus("fchown");
1650
TEMP_FAILURE_RETRY(close(pubkey_fd));
1654
/* Lower privileges */
1658
perror_plus("seteuid");
1662
/* Find network hooks and run them */
1664
struct dirent **direntries;
1665
struct dirent *direntry;
1666
int numhooks = scandir(HOOKDIR, &direntries, runnable_hook,
1668
int devnull = open("/dev/null", O_RDONLY);
1669
for(int i = 0; i < numhooks; i++){
1670
direntry = direntries[0];
1671
char *fullname = NULL;
1672
ret = asprintf(&fullname, "%s/%s", tempdir,
1675
perror_plus("asprintf");
1678
pid_t hook_pid = fork();
1681
dup2(devnull, STDIN_FILENO);
1683
dup2(STDERR_FILENO, STDOUT_FILENO);
1684
setenv("DEVICE", interface, 1);
1685
setenv("VERBOSE", debug ? "1" : "0", 1);
1686
setenv("MODE", "start", 1);
1687
/* setenv( XXX more here */
1688
ret = execl(fullname, direntry->d_name, "start");
1689
perror_plus("execl");
1700
1295
avahi_set_log_function(empty_log);
1703
1298
if(interface[0] == '\0'){
1704
1299
struct dirent **direntries;
1705
1300
ret = scandir(sys_class_net, &direntries, good_interface,
1762
1357
ret = sigaction(SIGINT, NULL, &old_sigterm_action);
1764
perror_plus("sigaction");
1359
perror("sigaction");
1765
1360
return EX_OSERR;
1767
1362
if(old_sigterm_action.sa_handler != SIG_IGN){
1768
1363
ret = sigaction(SIGINT, &sigterm_action, NULL);
1770
perror_plus("sigaction");
1365
perror("sigaction");
1771
1366
exitcode = EX_OSERR;
1775
1370
ret = sigaction(SIGHUP, NULL, &old_sigterm_action);
1777
perror_plus("sigaction");
1372
perror("sigaction");
1778
1373
return EX_OSERR;
1780
1375
if(old_sigterm_action.sa_handler != SIG_IGN){
1781
1376
ret = sigaction(SIGHUP, &sigterm_action, NULL);
1783
perror_plus("sigaction");
1378
perror("sigaction");
1784
1379
exitcode = EX_OSERR;
1788
1383
ret = sigaction(SIGTERM, NULL, &old_sigterm_action);
1790
perror_plus("sigaction");
1385
perror("sigaction");
1791
1386
return EX_OSERR;
1793
1388
if(old_sigterm_action.sa_handler != SIG_IGN){
1794
1389
ret = sigaction(SIGTERM, &sigterm_action, NULL);
1796
perror_plus("sigaction");
1391
perror("sigaction");
1797
1392
exitcode = EX_OSERR;
1892
1487
ret = seteuid(uid);
1894
perror_plus("seteuid");
1899
/* Sleep checking until interface is running.
1900
Check every 0.25s, up to total time of delay */
1494
/* sleep checking until interface is running */
1901
1495
for(int i=0; i < delay * 4; i++){
1902
1496
ret = ioctl(sd, SIOCGIFFLAGS, &network);
1904
perror_plus("ioctl SIOCGIFFLAGS");
1498
perror("ioctl SIOCGIFFLAGS");
1905
1499
} else if(network.ifr_flags & IFF_RUNNING){
1908
1502
struct timespec sleeptime = { .tv_nsec = 250000000 };
1909
1503
ret = nanosleep(&sleeptime, NULL);
1910
1504
if(ret == -1 and errno != EINTR){
1911
perror_plus("nanosleep");
1505
perror("nanosleep");
1914
1508
if(not take_down_interface){
1915
1509
/* We won't need the socket anymore */
1916
1510
ret = (int)TEMP_FAILURE_RETRY(close(sd));
1918
perror_plus("close");
1921
1515
#ifdef __linux__
2014
1609
port = (uint16_t)tmpmax;
2015
1610
*address = '\0';
1611
address = connect_to;
2016
1612
/* Colon in address indicates IPv6 */
2018
if(strchr(connect_to, ':') != NULL){
1614
if(strchr(address, ':') != NULL){
2020
/* Accept [] around IPv6 address - see RFC 5952 */
2021
if(connect_to[0] == '[' and address[-1] == ']')
2029
address = connect_to;
2035
1624
while(not quit_now){
2036
1625
ret = start_mandos_communication(address, port, if_index, af);
2037
1626
if(quit_now or ret == 0){
2041
fprintf(stderr, "Retrying in %d seconds\n",
2042
(int)retry_interval);
2044
sleep((int)retry_interval);
2047
1632
if (not quit_now){
2048
1633
exitcode = EXIT_SUCCESS;
2159
1726
ret = seteuid(0);
2161
perror_plus("seteuid");
2163
1730
if(geteuid() == 0){
2164
1731
ret = ioctl(sd, SIOCGIFFLAGS, &network);
2166
perror_plus("ioctl SIOCGIFFLAGS");
1733
perror("ioctl SIOCGIFFLAGS");
2167
1734
} else if(network.ifr_flags & IFF_UP) {
2168
1735
network.ifr_flags &= ~(short)IFF_UP; /* clear flag */
2169
1736
ret = ioctl(sd, SIOCSIFFLAGS, &network);
2171
perror_plus("ioctl SIOCSIFFLAGS -IFF_UP");
1738
perror("ioctl SIOCSIFFLAGS -IFF_UP");
2174
1741
ret = (int)TEMP_FAILURE_RETRY(close(sd));
2176
perror_plus("close");
2178
1745
/* Lower privileges permanently */
2180
1747
ret = setuid(uid);
2182
perror_plus("setuid");
2187
/* Removes the GPGME temp directory and all files inside */
1754
/* Removes the temp directory used by GPGME */
2188
1755
if(tempdir_created){
2189
struct dirent **direntries = NULL;
2190
struct dirent *direntry = NULL;
2191
int numentries = scandir(tempdir, &direntries, notdotentries,
2193
if (numentries > 0){
2194
for(int i = 0; i < numentries; i++){
2195
direntry = direntries[i];
1757
struct dirent *direntry;
1758
d = opendir(tempdir);
1760
if(errno != ENOENT){
1765
direntry = readdir(d);
1766
if(direntry == NULL){
1769
/* Skip "." and ".." */
1770
if(direntry->d_name[0] == '.'
1771
and (direntry->d_name[1] == '\0'
1772
or (direntry->d_name[1] == '.'
1773
and direntry->d_name[2] == '\0'))){
2196
1776
char *fullname = NULL;
2197
1777
ret = asprintf(&fullname, "%s/%s", tempdir,
2198
1778
direntry->d_name);
2200
perror_plus("asprintf");
2203
1783
ret = remove(fullname);