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00031 #define _GNU_SOURCE
00032
00033 #include <stdio.h>
00034 #include <stdlib.h>
00035 #include <syslog.h>
00036 #include <errno.h>
00037 #include <pthread.h>
00038 #include <sys/wait.h>
00039 #include <sys/types.h>
00040 #include <sys/unistd.h>
00041
00042 #include <string.h>
00043
00044 #include <sys/socket.h>
00045 #include <netinet/in.h>
00046 #include <arpa/inet.h>
00047 #include <unistd.h>
00048 #include <sys/uio.h>
00049 #include <fcntl.h>
00050 #include <netdb.h>
00051 #include <sys/time.h>
00052
00053 #ifdef __linux__
00054 #include <net/ethernet.h>
00055 #include <netinet/ip.h>
00056 #include <netinet/ip_icmp.h>
00057 #include <netpacket/packet.h>
00058 #endif
00059
00060 #include "httpd.h"
00061 #include "safe.h"
00062 #include "debug.h"
00063 #include "conf.h"
00064 #include "firewall.h"
00065 #include "fw_iptables.h"
00066 #include "auth.h"
00067 #include "centralserver.h"
00068 #include "client_list.h"
00069
00070 extern pthread_mutex_t client_list_mutex;
00071
00072
00073 extern pid_t restart_orig_pid;
00074
00075
00076
00085 int
00086 fw_allow(char *ip, char *mac, int fw_connection_state)
00087 {
00088 debug(LOG_DEBUG, "Allowing %s %s with fw_connection_state %d", ip, mac, fw_connection_state);
00089
00090 return iptables_fw_access(FW_ACCESS_ALLOW, ip, mac, fw_connection_state);
00091 }
00092
00100 int
00101 fw_deny(char *ip, char *mac, int fw_connection_state)
00102 {
00103 debug(LOG_DEBUG, "Denying %s %s with fw_connection_state %d", ip, mac, fw_connection_state);
00104
00105 return iptables_fw_access(FW_ACCESS_DENY, ip, mac, fw_connection_state);
00106 }
00107
00114 char *
00115 arp_get(char *req_ip)
00116 {
00117 FILE *proc;
00118 char ip[16];
00119 char mac[18];
00120 char * reply = NULL;
00121
00122 if (!(proc = fopen("/proc/net/arp", "r"))) {
00123 return NULL;
00124 }
00125
00126
00127 while (!feof(proc) && fgetc(proc) != '\n');
00128
00129
00130 reply = NULL;
00131 while (!feof(proc) && (fscanf(proc, " %15[0-9.] %*s %*s %17[A-F0-9:] %*s %*s", ip, mac) == 2)) {
00132 if (strcmp(ip, req_ip) == 0) {
00133 reply = safe_strdup(mac);
00134 break;
00135 }
00136 }
00137
00138 fclose(proc);
00139
00140 return reply;
00141 }
00142
00145 int
00146 fw_init(void)
00147 {
00148 int flags, oneopt = 1, zeroopt = 0;
00149 int result = 0;
00150 t_client * client = NULL;
00151
00152 debug(LOG_INFO, "Creating ICMP socket");
00153 if ((icmp_fd = socket (AF_INET, SOCK_RAW, IPPROTO_ICMP)) == -1 ||
00154 (flags = fcntl(icmp_fd, F_GETFL, 0)) == -1 ||
00155 fcntl(icmp_fd, F_SETFL, flags | O_NONBLOCK) == -1 ||
00156 setsockopt(icmp_fd, SOL_SOCKET, SO_RCVBUF, &oneopt, sizeof(oneopt)) ||
00157 setsockopt(icmp_fd, SOL_SOCKET, SO_DONTROUTE, &zeroopt, sizeof(zeroopt)) == -1) {
00158 debug(LOG_ERR, "Cannot create ICMP raw socket.");
00159 return;
00160 }
00161
00162 debug(LOG_INFO, "Initializing Firewall");
00163 result = iptables_fw_init();
00164
00165 if (restart_orig_pid) {
00166 debug(LOG_INFO, "Restoring firewall rules for clients inherited from parent");
00167 LOCK_CLIENT_LIST();
00168 client = client_get_first_client();
00169 while (client) {
00170 fw_allow(client->ip, client->mac, client->fw_connection_state);
00171 client = client->next;
00172 }
00173 UNLOCK_CLIENT_LIST();
00174 }
00175
00176 return result;
00177 }
00178
00181 void
00182 fw_clear_authservers(void)
00183 {
00184 debug(LOG_INFO, "Clearing the authservers list");
00185 iptables_fw_clear_authservers();
00186 }
00187
00190 void
00191 fw_set_authservers(void)
00192 {
00193 debug(LOG_INFO, "Setting the authservers list");
00194 iptables_fw_set_authservers();
00195 }
00196
00201 int
00202 fw_destroy(void)
00203 {
00204 if (icmp_fd != 0) {
00205 debug(LOG_INFO, "Closing ICMP socket");
00206 close(icmp_fd);
00207 }
00208
00209 debug(LOG_INFO, "Removing Firewall rules");
00210 return iptables_fw_destroy();
00211 }
00212
00216 void
00217 fw_sync_with_authserver(void)
00218 {
00219 t_authresponse authresponse;
00220 char *token, *ip, *mac;
00221 t_client *p1, *p2;
00222 unsigned long long incoming, outgoing;
00223 s_config *config = config_get_config();
00224
00225 if (-1 == iptables_fw_counters_update()) {
00226 debug(LOG_ERR, "Could not get counters from firewall!");
00227 return;
00228 }
00229
00230 LOCK_CLIENT_LIST();
00231
00232 for (p1 = p2 = client_get_first_client(); NULL != p1; p1 = p2) {
00233 p2 = p1->next;
00234
00235 ip = safe_strdup(p1->ip);
00236 token = safe_strdup(p1->token);
00237 mac = safe_strdup(p1->mac);
00238 outgoing = p1->counters.outgoing;
00239 incoming = p1->counters.incoming;
00240
00241 UNLOCK_CLIENT_LIST();
00242
00243
00244
00245
00246 icmp_ping(ip);
00247
00248 if (config->auth_servers != NULL) {
00249 auth_server_request(&authresponse, REQUEST_TYPE_COUNTERS, ip, mac, token, incoming, outgoing);
00250 }
00251 LOCK_CLIENT_LIST();
00252
00253 if (!(p1 = client_list_find(ip, mac))) {
00254 debug(LOG_ERR, "Node %s was freed while being re-validated!", ip);
00255 } else {
00256 if (p1->counters.last_updated +
00257 (config->checkinterval * config->clienttimeout)
00258 <= time(NULL)) {
00259
00260 debug(LOG_INFO, "%s - Inactive for %ld seconds, removing client and denying in firewall",
00261 p1->ip, config->checkinterval * config->clienttimeout);
00262 fw_deny(p1->ip, p1->mac, p1->fw_connection_state);
00263 client_list_delete(p1);
00264
00265
00266 if (config->auth_servers != NULL) {
00267 UNLOCK_CLIENT_LIST();
00268 auth_server_request(&authresponse, REQUEST_TYPE_LOGOUT, ip, mac, token, 0, 0);
00269 LOCK_CLIENT_LIST();
00270 }
00271 } else {
00272
00273
00274
00275
00276
00277
00278
00279
00280
00281 if (config->auth_servers != NULL) {
00282 switch (authresponse.authcode) {
00283 case AUTH_DENIED:
00284 debug(LOG_NOTICE, "%s - Denied. Removing client and firewall rules", p1->ip);
00285 fw_deny(p1->ip, p1->mac, p1->fw_connection_state);
00286 client_list_delete(p1);
00287 break;
00288
00289 case AUTH_VALIDATION_FAILED:
00290 debug(LOG_NOTICE, "%s - Validation timeout, now denied. Removing client and firewall rules", p1->ip);
00291 fw_deny(p1->ip, p1->mac, p1->fw_connection_state);
00292 client_list_delete(p1);
00293 break;
00294
00295 case AUTH_ALLOWED:
00296 if (p1->fw_connection_state != FW_MARK_KNOWN) {
00297 debug(LOG_INFO, "%s - Access has changed to allowed, refreshing firewall and clearing counters", p1->ip);
00298
00299
00300
00301 if (p1->fw_connection_state != FW_MARK_PROBATION) {
00302 p1->counters.incoming = p1->counters.outgoing = 0;
00303 }
00304 else {
00305
00306 debug(LOG_INFO, "%s - Skipped clearing counters after all, the user was previously in validation", p1->ip);
00307 }
00308 p1->fw_connection_state = FW_MARK_KNOWN;
00309 fw_allow(p1->ip, p1->mac, p1->fw_connection_state);
00310 }
00311 break;
00312
00313 case AUTH_VALIDATION:
00314
00315
00316
00317
00318
00319 debug(LOG_INFO, "%s - User in validation period", p1->ip);
00320 break;
00321
00322 case AUTH_ERROR:
00323 debug(LOG_WARNING, "Error communicating with auth server - leaving %s as-is for now", p1->ip);
00324 break;
00325
00326 default:
00327 debug(LOG_ERR, "I do not know about authentication code %d", authresponse.authcode);
00328 break;
00329 }
00330 }
00331 }
00332 }
00333
00334 free(token);
00335 free(ip);
00336 free(mac);
00337 }
00338 UNLOCK_CLIENT_LIST();
00339 }
00340
00341 void icmp_ping(char *host) {
00342 struct sockaddr_in saddr;
00343 #ifdef __linux__
00344 struct {
00345 struct ip ip;
00346 struct icmp icmp;
00347 } packet;
00348 #endif
00349 unsigned int i, j;
00350 int opt = 2000;
00351 unsigned short id = rand16();
00352
00353 saddr.sin_family = AF_INET;
00354 saddr.sin_port = 0;
00355 inet_aton(host, &saddr.sin_addr);
00356 #ifdef HAVE_SOCKADDR_SA_LEN
00357 saddr.sin_len = sizeof(struct sockaddr_in);
00358 #endif
00359
00360 memset(&(saddr.sin_zero), '\0', sizeof(saddr.sin_zero));
00361
00362 #ifdef __linux__
00363 memset(&packet.icmp, 0, sizeof(packet.icmp));
00364 packet.icmp.icmp_type = ICMP_ECHO;
00365 packet.icmp.icmp_id = id;
00366 for (j = 0, i = 0; i < sizeof(struct icmp) / 2; i++)
00367 j += ((unsigned short *)&packet.icmp)[i];
00368 while (j>>16)
00369 j = (j & 0xffff) + (j >> 16);
00370 packet.icmp.icmp_cksum = (j == 0xffff) ? j : ~j;
00371
00372 if (setsockopt(icmp_fd, SOL_SOCKET, SO_RCVBUF, &opt, sizeof(opt)) == -1) {
00373 debug(LOG_ERR, "setsockopt(): %s", strerror(errno));
00374 }
00375 if (sendto(icmp_fd, (char *)&packet.icmp, sizeof(struct icmp), 0, (struct sockaddr *)&saddr, sizeof(saddr)) == -1) {
00376 debug(LOG_ERR, "sendto(): %s", strerror(errno));
00377 }
00378 opt = 1;
00379 if (setsockopt(icmp_fd, SOL_SOCKET, SO_RCVBUF, &opt, sizeof(opt)) == -1) {
00380 debug(LOG_ERR, "setsockopt(): %s", strerror(errno));
00381 }
00382 #endif
00383
00384 return;
00385 }
00386
00387 unsigned short rand16(void) {
00388 static int been_seeded = 0;
00389
00390 if (!been_seeded) {
00391 int fd, n = 0;
00392 unsigned int c = 0, seed = 0;
00393 char sbuf[sizeof(seed)];
00394 char *s;
00395 struct timeval now;
00396
00397
00398 gettimeofday(&now, NULL);
00399 seed = now.tv_sec ^ now.tv_usec ^ (getpid() << 16);
00400
00401 srand(seed);
00402 been_seeded = 1;
00403 }
00404
00405
00406
00407
00408
00409
00410 return( (unsigned short) (rand() >> 15) );
00411 }