| 1 | /********************************************************************\ |
|---|
| 2 | * This program is free software; you can redistribute it and/or * |
|---|
| 3 | * modify it under the terms of the GNU General Public License as * |
|---|
| 4 | * published by the Free Software Foundation; either version 2 of * |
|---|
| 5 | * the License, or (at your option) any later version. * |
|---|
| 6 | * * |
|---|
| 7 | * This program is distributed in the hope that it will be useful, * |
|---|
| 8 | * but WITHOUT ANY WARRANTY; without even the implied warranty of * |
|---|
| 9 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * |
|---|
| 10 | * GNU General Public License for more details. * |
|---|
| 11 | * * |
|---|
| 12 | * You should have received a copy of the GNU General Public License* |
|---|
| 13 | * along with this program; if not, contact: * |
|---|
| 14 | * * |
|---|
| 15 | * Free Software Foundation Voice: +1-617-542-5942 * |
|---|
| 16 | * 59 Temple Place - Suite 330 Fax: +1-617-542-2652 * |
|---|
| 17 | * Boston, MA 02111-1307, USA gnu@gnu.org * |
|---|
| 18 | * * |
|---|
| 19 | \********************************************************************/ |
|---|
| 20 | |
|---|
| 21 | /* $Header$ */ |
|---|
| 22 | /** @internal |
|---|
| 23 | @file fw_iptables.c |
|---|
| 24 | @brief Firewall iptables functions |
|---|
| 25 | @author Copyright (C) 2004 Philippe April <papril777@yahoo.com> |
|---|
| 26 | */ |
|---|
| 27 | |
|---|
| 28 | #define _GNU_SOURCE |
|---|
| 29 | |
|---|
| 30 | #include <stdio.h> |
|---|
| 31 | #include <stdlib.h> |
|---|
| 32 | #include <stdarg.h> |
|---|
| 33 | #include <syslog.h> |
|---|
| 34 | #include <errno.h> |
|---|
| 35 | #include <string.h> |
|---|
| 36 | #include <pthread.h> |
|---|
| 37 | |
|---|
| 38 | #include "conf.h" |
|---|
| 39 | #include "fw_iptables.h" |
|---|
| 40 | #include "firewall.h" |
|---|
| 41 | #include "debug.h" |
|---|
| 42 | #include "util.h" |
|---|
| 43 | #include "client_list.h" |
|---|
| 44 | |
|---|
| 45 | static int iptables_do_command(char *format, ...); |
|---|
| 46 | |
|---|
| 47 | extern pthread_mutex_t client_list_mutex; |
|---|
| 48 | |
|---|
| 49 | /** |
|---|
| 50 | Used to supress the error output of the firewall during destruction */ |
|---|
| 51 | static int fw_quiet = 0; |
|---|
| 52 | |
|---|
| 53 | /** @internal */ |
|---|
| 54 | static int |
|---|
| 55 | iptables_do_command(char *format, ...) |
|---|
| 56 | { |
|---|
| 57 | va_list vlist; |
|---|
| 58 | char *fmt_cmd, |
|---|
| 59 | *cmd; |
|---|
| 60 | int rc; |
|---|
| 61 | |
|---|
| 62 | va_start(vlist, format); |
|---|
| 63 | vasprintf(&fmt_cmd, format, vlist); |
|---|
| 64 | asprintf(&cmd, "iptables %s", fmt_cmd); |
|---|
| 65 | |
|---|
| 66 | rc = execute(cmd, fw_quiet); |
|---|
| 67 | |
|---|
| 68 | free(fmt_cmd); |
|---|
| 69 | free(cmd); |
|---|
| 70 | |
|---|
| 71 | return rc; |
|---|
| 72 | } |
|---|
| 73 | |
|---|
| 74 | /** Initialize the firewall rules |
|---|
| 75 | */ |
|---|
| 76 | int |
|---|
| 77 | iptables_fw_init(void) |
|---|
| 78 | { |
|---|
| 79 | s_config *config = config_get_config(); |
|---|
| 80 | fw_quiet = 0; |
|---|
| 81 | iptables_do_command("-t nat -N " TABLE_WIFIDOG_VALIDATE); |
|---|
| 82 | iptables_do_command("-t nat -A " TABLE_WIFIDOG_VALIDATE " -d %s -j ACCEPT", config->gw_address); |
|---|
| 83 | iptables_do_command("-t nat -A " TABLE_WIFIDOG_VALIDATE " -d %s -j ACCEPT", config->auth_servers->authserv_hostname); |
|---|
| 84 | iptables_do_command("-t nat -A " TABLE_WIFIDOG_VALIDATE " -p udp --dport 67 -j ACCEPT"); |
|---|
| 85 | iptables_do_command("-t nat -A " TABLE_WIFIDOG_VALIDATE " -p tcp --dport 67 -j ACCEPT"); |
|---|
| 86 | iptables_do_command("-t nat -A " TABLE_WIFIDOG_VALIDATE " -p udp --dport 53 -j ACCEPT"); |
|---|
| 87 | iptables_do_command("-t nat -A " TABLE_WIFIDOG_VALIDATE " -p tcp --dport 80 -j ACCEPT"); |
|---|
| 88 | iptables_do_command("-t nat -A " TABLE_WIFIDOG_VALIDATE " -p tcp --dport 110 -j ACCEPT"); |
|---|
| 89 | iptables_do_command("-t nat -A " TABLE_WIFIDOG_VALIDATE " -p tcp --dport 995 -j ACCEPT"); |
|---|
| 90 | iptables_do_command("-t nat -A " TABLE_WIFIDOG_VALIDATE " -p tcp --dport 143 -j ACCEPT"); |
|---|
| 91 | iptables_do_command("-t nat -A " TABLE_WIFIDOG_VALIDATE " -p tcp --dport 993 -j ACCEPT"); |
|---|
| 92 | iptables_do_command("-t nat -A " TABLE_WIFIDOG_VALIDATE " -p tcp --dport 220 -j ACCEPT"); |
|---|
| 93 | iptables_do_command("-t nat -A " TABLE_WIFIDOG_VALIDATE " -p tcp --dport 993 -j ACCEPT"); |
|---|
| 94 | iptables_do_command("-t nat -A " TABLE_WIFIDOG_VALIDATE " -p tcp --dport 443 -j ACCEPT"); |
|---|
| 95 | iptables_do_command("-t nat -A " TABLE_WIFIDOG_VALIDATE " -j DROP"); |
|---|
| 96 | |
|---|
| 97 | iptables_do_command("-t nat -N " TABLE_WIFIDOG_UNKNOWN); |
|---|
| 98 | iptables_do_command("-t nat -A " TABLE_WIFIDOG_UNKNOWN " -d %s -j ACCEPT", config->gw_address); |
|---|
| 99 | iptables_do_command("-t nat -A " TABLE_WIFIDOG_UNKNOWN " -d %s -j ACCEPT", config->auth_servers->authserv_hostname); |
|---|
| 100 | iptables_do_command("-t nat -A " TABLE_WIFIDOG_UNKNOWN " -p udp --dport 67 -j ACCEPT"); |
|---|
| 101 | iptables_do_command("-t nat -A " TABLE_WIFIDOG_UNKNOWN " -p tcp --dport 67 -j ACCEPT"); |
|---|
| 102 | iptables_do_command("-t nat -A " TABLE_WIFIDOG_UNKNOWN " -p udp --dport 53 -j ACCEPT"); |
|---|
| 103 | iptables_do_command("-t nat -A " TABLE_WIFIDOG_UNKNOWN " -p tcp --dport 80 -j REDIRECT --to-ports %d", config->gw_port); |
|---|
| 104 | iptables_do_command("-t nat -A " TABLE_WIFIDOG_UNKNOWN " -j DROP"); |
|---|
| 105 | |
|---|
| 106 | iptables_do_command("-t nat -N " TABLE_WIFIDOG_KNOWN); |
|---|
| 107 | iptables_do_command("-t nat -A " TABLE_WIFIDOG_KNOWN " -j ACCEPT"); |
|---|
| 108 | |
|---|
| 109 | iptables_do_command("-t nat -N " TABLE_WIFIDOG_LOCKED); |
|---|
| 110 | iptables_do_command("-t nat -A " TABLE_WIFIDOG_LOCKED " -j DROP"); |
|---|
| 111 | |
|---|
| 112 | iptables_do_command("-t nat -N " TABLE_WIFIDOG_CLASS); |
|---|
| 113 | iptables_do_command("-t nat -A " TABLE_WIFIDOG_CLASS " -i %s -m mark --mark 0x%u -j " TABLE_WIFIDOG_VALIDATE, config->gw_interface, FW_MARK_PROBATION); |
|---|
| 114 | iptables_do_command("-t nat -A " TABLE_WIFIDOG_CLASS " -i %s -m mark --mark 0x%u -j " TABLE_WIFIDOG_KNOWN, config->gw_interface, FW_MARK_KNOWN); |
|---|
| 115 | iptables_do_command("-t nat -A " TABLE_WIFIDOG_CLASS " -i %s -m mark --mark 0x%u -j " TABLE_WIFIDOG_LOCKED, config->gw_interface, FW_MARK_LOCKED); |
|---|
| 116 | iptables_do_command("-t nat -A " TABLE_WIFIDOG_CLASS " -i %s -j " TABLE_WIFIDOG_UNKNOWN, config->gw_interface); |
|---|
| 117 | iptables_do_command("-t nat -I PREROUTING 1 -i %s -j " TABLE_WIFIDOG_CLASS, config->gw_interface); |
|---|
| 118 | |
|---|
| 119 | iptables_do_command("-t mangle -N " TABLE_WIFIDOG_OUTGOING); |
|---|
| 120 | iptables_do_command("-t mangle -I PREROUTING 1 -i %s -j " TABLE_WIFIDOG_OUTGOING, config->gw_interface); |
|---|
| 121 | |
|---|
| 122 | iptables_do_command("-t mangle -N " TABLE_WIFIDOG_INCOMING); |
|---|
| 123 | iptables_do_command("-t mangle -I FORWARD 1 -i %s -j " TABLE_WIFIDOG_INCOMING, config->external_interface); |
|---|
| 124 | |
|---|
| 125 | return 1; |
|---|
| 126 | } |
|---|
| 127 | |
|---|
| 128 | /** Remove the firewall rules |
|---|
| 129 | * This is used when we do a clean shutdown of WiFiDog and when it starts to make |
|---|
| 130 | * sure there are no rules left over |
|---|
| 131 | */ |
|---|
| 132 | int |
|---|
| 133 | iptables_fw_destroy(void) |
|---|
| 134 | { |
|---|
| 135 | int rc; |
|---|
| 136 | s_config *config = config_get_config(); |
|---|
| 137 | |
|---|
| 138 | fw_quiet = 1; |
|---|
| 139 | iptables_do_command("-t nat -F " TABLE_WIFIDOG_CLASS); |
|---|
| 140 | iptables_do_command("-t mangle -F " TABLE_WIFIDOG_OUTGOING); |
|---|
| 141 | iptables_do_command("-t mangle -F " TABLE_WIFIDOG_INCOMING); |
|---|
| 142 | |
|---|
| 143 | iptables_do_command("-t nat -F " TABLE_WIFIDOG_VALIDATE); |
|---|
| 144 | iptables_do_command("-t nat -F " TABLE_WIFIDOG_UNKNOWN); |
|---|
| 145 | iptables_do_command("-t nat -F " TABLE_WIFIDOG_KNOWN); |
|---|
| 146 | iptables_do_command("-t nat -F " TABLE_WIFIDOG_LOCKED); |
|---|
| 147 | iptables_do_command("-t nat -X " TABLE_WIFIDOG_VALIDATE); |
|---|
| 148 | iptables_do_command("-t nat -X " TABLE_WIFIDOG_UNKNOWN); |
|---|
| 149 | iptables_do_command("-t nat -X " TABLE_WIFIDOG_KNOWN); |
|---|
| 150 | iptables_do_command("-t nat -X " TABLE_WIFIDOG_LOCKED); |
|---|
| 151 | |
|---|
| 152 | /* We loop in case wifidog has crashed and left some unwanted rules, |
|---|
| 153 | * maybe we shouldn't loop forever, we'll try anyway |
|---|
| 154 | */ |
|---|
| 155 | rc = 0; |
|---|
| 156 | while (rc == 0) { |
|---|
| 157 | rc = iptables_do_command("-t nat -D PREROUTING -i %s -j " TABLE_WIFIDOG_CLASS, config->gw_interface); |
|---|
| 158 | } |
|---|
| 159 | iptables_do_command("-t nat -X " TABLE_WIFIDOG_CLASS); |
|---|
| 160 | |
|---|
| 161 | rc = 0; |
|---|
| 162 | while (rc == 0) { |
|---|
| 163 | rc = iptables_do_command("-t mangle -D PREROUTING -i %s -j " TABLE_WIFIDOG_OUTGOING, config->gw_interface); |
|---|
| 164 | } |
|---|
| 165 | iptables_do_command("-t mangle -X " TABLE_WIFIDOG_OUTGOING); |
|---|
| 166 | |
|---|
| 167 | rc = 0; |
|---|
| 168 | while (rc == 0) { |
|---|
| 169 | rc = iptables_do_command("-t mangle -D FORWARD -i %s -j " TABLE_WIFIDOG_INCOMING, config->external_interface); |
|---|
| 170 | } |
|---|
| 171 | iptables_do_command("-t mangle -X " TABLE_WIFIDOG_INCOMING); |
|---|
| 172 | |
|---|
| 173 | return 1; |
|---|
| 174 | } |
|---|
| 175 | |
|---|
| 176 | /** Set the firewall access for a specific client */ |
|---|
| 177 | int |
|---|
| 178 | iptables_fw_access(fw_access_t type, char *ip, char *mac, int tag) |
|---|
| 179 | { |
|---|
| 180 | int rc; |
|---|
| 181 | |
|---|
| 182 | fw_quiet = 0; |
|---|
| 183 | |
|---|
| 184 | switch(type) { |
|---|
| 185 | case FW_ACCESS_ALLOW: |
|---|
| 186 | iptables_do_command("-t mangle -A " TABLE_WIFIDOG_OUTGOING " -s %s -m mac --mac-source %s -j MARK --set-mark %d", ip, mac, tag); |
|---|
| 187 | rc = iptables_do_command("-t mangle -A " TABLE_WIFIDOG_INCOMING " -d %s -j ACCEPT", ip); |
|---|
| 188 | break; |
|---|
| 189 | case FW_ACCESS_DENY: |
|---|
| 190 | iptables_do_command("-t mangle -D " TABLE_WIFIDOG_OUTGOING " -s %s -m mac --mac-source %s -j MARK --set-mark %d", ip, mac, tag); |
|---|
| 191 | rc = iptables_do_command("-t mangle -D " TABLE_WIFIDOG_INCOMING " -d %s -j ACCEPT", ip); |
|---|
| 192 | break; |
|---|
| 193 | default: |
|---|
| 194 | rc = -1; |
|---|
| 195 | break; |
|---|
| 196 | } |
|---|
| 197 | |
|---|
| 198 | return rc; |
|---|
| 199 | } |
|---|
| 200 | |
|---|
| 201 | /** Update the counters of all the clients in the client list */ |
|---|
| 202 | int |
|---|
| 203 | iptables_fw_counters_update(void) |
|---|
| 204 | { |
|---|
| 205 | FILE *output; |
|---|
| 206 | char *script, |
|---|
| 207 | ip[16], |
|---|
| 208 | rc; |
|---|
| 209 | unsigned long int counter; |
|---|
| 210 | t_client *p1; |
|---|
| 211 | |
|---|
| 212 | /* Look for outgoing traffic */ |
|---|
| 213 | asprintf(&script, "%s %s", "iptables", "-v -x -t mangle -L " TABLE_WIFIDOG_OUTGOING); |
|---|
| 214 | if (!(output = popen(script, "r"))) { |
|---|
| 215 | debug(LOG_ERR, "popen(): %s", strerror(errno)); |
|---|
| 216 | return -1; |
|---|
| 217 | } |
|---|
| 218 | free(script); |
|---|
| 219 | |
|---|
| 220 | /* skip the first two lines */ |
|---|
| 221 | while (('\n' != fgetc(output)) && !feof(output)) |
|---|
| 222 | ; |
|---|
| 223 | while (('\n' != fgetc(output)) && !feof(output)) |
|---|
| 224 | ; |
|---|
| 225 | while (output && !(feof(output))) { |
|---|
| 226 | rc = fscanf(output, "%*s %lu %*s %*s %*s %*s %*s %s %*s %*s %*s %*s %*s 0x%*u", &counter, ip); |
|---|
| 227 | if (2 == rc && EOF != rc) { |
|---|
| 228 | debug(LOG_DEBUG, "Outgoing %s Bytes=%ld", ip, counter); |
|---|
| 229 | pthread_mutex_lock(&client_list_mutex); |
|---|
| 230 | if ((p1 = client_list_find_by_ip(ip))) { |
|---|
| 231 | if (p1->counters.outgoing < counter) { |
|---|
| 232 | p1->counters.outgoing = counter; |
|---|
| 233 | p1->counters.last_updated = time(NULL); |
|---|
| 234 | debug(LOG_DEBUG, "%s - Updated counter to %ld bytes", ip, counter); |
|---|
| 235 | } |
|---|
| 236 | } else { |
|---|
| 237 | debug(LOG_ERR, "Could not find %s in client list", ip); |
|---|
| 238 | } |
|---|
| 239 | pthread_mutex_unlock(&client_list_mutex); |
|---|
| 240 | } |
|---|
| 241 | } |
|---|
| 242 | pclose(output); |
|---|
| 243 | |
|---|
| 244 | /* Look for incoming traffic */ |
|---|
| 245 | asprintf(&script, "%s %s", "iptables", "-v -x -t mangle -L " TABLE_WIFIDOG_INCOMING); |
|---|
| 246 | if (!(output = popen(script, "r"))) { |
|---|
| 247 | debug(LOG_ERR, "popen(): %s", strerror(errno)); |
|---|
| 248 | return -1; |
|---|
| 249 | } |
|---|
| 250 | free(script); |
|---|
| 251 | |
|---|
| 252 | /* skip the first two lines */ |
|---|
| 253 | while (('\n' != fgetc(output)) && !feof(output)) |
|---|
| 254 | ; |
|---|
| 255 | while (('\n' != fgetc(output)) && !feof(output)) |
|---|
| 256 | ; |
|---|
| 257 | while (output && !(feof(output))) { |
|---|
| 258 | rc = fscanf(output, "%*s %lu %*s %*s %*s %*s %*s %*s %s", &counter, ip); |
|---|
| 259 | if (2 == rc && EOF != rc) { |
|---|
| 260 | debug(LOG_DEBUG, "Incoming %s Bytes=%ld", ip, counter); |
|---|
| 261 | pthread_mutex_lock(&client_list_mutex); |
|---|
| 262 | if ((p1 = client_list_find_by_ip(ip))) { |
|---|
| 263 | if (p1->counters.incoming < counter) { |
|---|
| 264 | p1->counters.incoming = counter; |
|---|
| 265 | p1->counters.last_updated = time(NULL); |
|---|
| 266 | debug(LOG_DEBUG, "%s - Updated counter to %ld bytes", ip, counter); |
|---|
| 267 | } |
|---|
| 268 | } else { |
|---|
| 269 | debug(LOG_ERR, "Could not find %s in client list", ip); |
|---|
| 270 | } |
|---|
| 271 | pthread_mutex_unlock(&client_list_mutex); |
|---|
| 272 | } |
|---|
| 273 | } |
|---|
| 274 | pclose(output); |
|---|
| 275 | |
|---|
| 276 | return 1; |
|---|
| 277 | } |
|---|
| 278 | |
|---|