src/initscripts/init.d/firewall

   1 #!/bin/sh
   2
   3 . /etc/sysconfig/rc
   4 . ${rc_functions}
   5
   6 eval $(/usr/local/bin/readhash /var/ipfire/ppp/settings)
   7 eval $(/usr/local/bin/readhash /var/ipfire/ethernet/settings)
   8 eval $(/usr/local/bin/readhash /var/ipfire/optionsfw/settings)
   9 IFACE=`/bin/cat /var/ipfire/red/iface 2> /dev/null | /usr/bin/tr -d '\012'`
  10
  11 if [ -f /var/ipfire/red/device ]; then
  12         DEVICE=`/bin/cat /var/ipfire/red/device 2> /dev/null | /usr/bin/tr -d '\012'`
  13 fi
  14
  15 function iptables() {
  16         /sbin/iptables --wait "$@"
  17 }
  18
  19 iptables_init() {
  20         # Flush all rules and delete all custom chains
  21         iptables -F
  22         iptables -t nat -F
  23         iptables -t mangle -F
  24         iptables -X
  25         iptables -t nat -X
  26         iptables -t mangle -X
  27
  28         # Set up policies
  29         iptables -P INPUT DROP
  30         iptables -P FORWARD DROP
  31         iptables -P OUTPUT ACCEPT
  32
  33         # Empty LOG_DROP and LOG_REJECT chains
  34         iptables -N LOG_DROP
  35         iptables -A LOG_DROP   -m limit --limit 10/minute -j LOG
  36         iptables -A LOG_DROP   -j DROP
  37         iptables -N LOG_REJECT
  38         iptables -A LOG_REJECT -m limit --limit 10/minute -j LOG
  39         iptables -A LOG_REJECT -j REJECT
  40
  41         # This chain will log, then DROPs packets with certain bad combinations
  42         # of flags might indicate a port-scan attempt (xmas, null, etc)
  43         iptables -N PSCAN
  44         if [ "$DROPPORTSCAN" == "on" ]; then
  45                 iptables -A PSCAN -p tcp  -m limit --limit 10/minute -j LOG --log-prefix "DROP_TCP Scan " -m comment --comment "DROP_TCP PScan"
  46                 iptables -A PSCAN -p udp  -m limit --limit 10/minute -j LOG --log-prefix "DROP_UDP Scan " -m comment --comment "DROP_UDP PScan"
  47                 iptables -A PSCAN -p icmp -m limit --limit 10/minute -j LOG --log-prefix "DROP_ICMP Scan " -m comment --comment "DROP_ICMP PScan"
  48                 iptables -A PSCAN -f      -m limit --limit 10/minute -j LOG --log-prefix "DROP_FRAG Scan " -m comment --comment "DROP_FRAG PScan"
  49         fi
  50         iptables -A PSCAN -j DROP -m comment --comment "DROP_PScan"
  51
  52         # New tcp packets without SYN set - could well be an obscure type of port scan
  53         # that's not covered above, may just be a broken windows machine
  54         iptables -N NEWNOTSYN
  55         if [ "$DROPNEWNOTSYN" == "on" ]; then
  56                 iptables -A NEWNOTSYN  -m limit --limit 10/minute -j LOG  --log-prefix "DROP_NEWNOTSYN "
  57         fi
  58         iptables -A NEWNOTSYN  -j DROP -m comment --comment "DROP_NEWNOTSYN"
  59
  60         # Chain to contain all the rules relating to bad TCP flags
  61         iptables -N BADTCP
  62
  63         # Don't check loopback
  64         iptables -A BADTCP -i lo -j RETURN
  65
  66         # Disallow packets frequently used by port-scanners
  67         # nmap xmas
  68         iptables -A BADTCP -p tcp --tcp-flags ALL FIN,URG,PSH  -j PSCAN
  69         # Null
  70         iptables -A BADTCP -p tcp --tcp-flags ALL NONE -j PSCAN
  71         # FIN
  72         iptables -A BADTCP -p tcp --tcp-flags ALL FIN -j PSCAN
  73         # SYN/RST (also catches xmas variants that set SYN+RST+...)
  74         iptables -A BADTCP -p tcp --tcp-flags SYN,RST SYN,RST -j PSCAN
  75         # SYN/FIN (QueSO or nmap OS probe)
  76         iptables -A BADTCP -p tcp --tcp-flags SYN,FIN SYN,FIN -j PSCAN
  77         # NEW TCP without SYN
  78         iptables -A BADTCP -p tcp ! --syn -m conntrack --ctstate NEW -j NEWNOTSYN
  79
  80         iptables -A INPUT   -p tcp -j BADTCP
  81         iptables -A FORWARD -p tcp -j BADTCP
  82
  83         # Connection tracking chain
  84         iptables -N CONNTRACK
  85         iptables -A CONNTRACK -m conntrack --ctstate ESTABLISHED,RELATED -j ACCEPT
  86
  87         # Fix for braindead ISP's
  88         iptables -A FORWARD -p tcp --tcp-flags SYN,RST SYN -j TCPMSS --clamp-mss-to-pmtu
  89
  90         # CUSTOM chains, can be used by the users themselves
  91         iptables -N CUSTOMINPUT
  92         iptables -A INPUT -j CUSTOMINPUT
  93         iptables -N CUSTOMFORWARD
  94         iptables -A FORWARD -j CUSTOMFORWARD
  95         iptables -N CUSTOMOUTPUT
  96         iptables -A OUTPUT -j CUSTOMOUTPUT
  97         iptables -t nat -N CUSTOMPREROUTING
  98         iptables -t nat -A PREROUTING -j CUSTOMPREROUTING
  99         iptables -t nat -N CUSTOMPOSTROUTING
 100         iptables -t nat -A POSTROUTING -j CUSTOMPOSTROUTING
 101
 102         # Guardian (IPS) chains
 103         iptables -N GUARDIAN
 104         iptables -A INPUT -j GUARDIAN
 105         iptables -A FORWARD -j GUARDIAN
 106
 107         # Block OpenVPN transfer networks
 108         iptables -N OVPNBLOCK
 109         for i in INPUT FORWARD; do
 110                 iptables -A ${i} -j OVPNBLOCK
 111         done
 112
 113         # OpenVPN transfer network translation
 114         iptables -t nat -N OVPNNAT
 115         iptables -t nat -A POSTROUTING -j OVPNNAT
 116
 117         # IPTV chains for IGMPPROXY
 118         iptables -N IPTVINPUT
 119         iptables -A INPUT -j IPTVINPUT
 120         iptables -N IPTVFORWARD
 121         iptables -A FORWARD -j IPTVFORWARD
 122
 123         # filtering from GUI
 124         iptables -N GUIINPUT
 125         iptables -A INPUT -j GUIINPUT
 126         iptables -A GUIINPUT -p icmp --icmp-type 8 -j ACCEPT
 127
 128         # Accept everything on loopback
 129         iptables -N LOOPBACK
 130         iptables -A LOOPBACK -i lo -j ACCEPT
 131         iptables -A LOOPBACK -o lo -j ACCEPT
 132
 133         # Filter all packets with loopback addresses on non-loopback interfaces.
 134         iptables -A LOOPBACK -s 127.0.0.0/8 -j DROP
 135         iptables -A LOOPBACK -d 127.0.0.0/8 -j DROP
 136
 137         for i in INPUT FORWARD OUTPUT; do
 138                 iptables -A ${i} -j LOOPBACK
 139         done
 140
 141         # Accept everything connected
 142         for i in INPUT FORWARD OUTPUT; do
 143                 iptables -A ${i} -j CONNTRACK
 144         done
 145
 146         # trafic from ipsecX/TUN/TAP interfaces, before "-i GREEN_DEV" accept everything
 147         iptables -N IPSECINPUT
 148         iptables -N IPSECFORWARD
 149         iptables -N IPSECOUTPUT
 150         iptables -A INPUT -j IPSECINPUT
 151         iptables -A FORWARD -j IPSECFORWARD
 152         iptables -A OUTPUT -j IPSECOUTPUT
 153         iptables -t nat -N IPSECNAT
 154         iptables -t nat -A POSTROUTING -j IPSECNAT
 155
 156         # localhost and ethernet.
 157         iptables -A INPUT   -i $GREEN_DEV  -m conntrack --ctstate NEW -j ACCEPT ! -p icmp
 158
 159         # allow DHCP on BLUE to be turned on/off
 160         iptables -N DHCPBLUEINPUT
 161         iptables -A INPUT -j DHCPBLUEINPUT
 162
 163         # WIRELESS chains
 164         iptables -N WIRELESSINPUT
 165         iptables -A INPUT -m conntrack --ctstate NEW -j WIRELESSINPUT
 166         iptables -N WIRELESSFORWARD
 167         iptables -A FORWARD -m conntrack --ctstate NEW -j WIRELESSFORWARD
 168
 169         # OpenVPN
 170         iptables -N OVPNINPUT
 171         iptables -A INPUT -j OVPNINPUT
 172
 173         # TOR
 174         iptables -N TOR_INPUT
 175         iptables -A INPUT -j TOR_INPUT
 176
 177         # Jump into the actual firewall ruleset.
 178         iptables -N INPUTFW
 179         iptables -A INPUT -j INPUTFW
 180
 181         iptables -N OUTGOINGFW
 182         iptables -A OUTPUT -j OUTGOINGFW
 183
 184         iptables -N FORWARDFW
 185         iptables -A FORWARD -j FORWARDFW
 186
 187         # SNAT rules
 188         iptables -t nat -N NAT_SOURCE
 189         iptables -t nat -A POSTROUTING -j NAT_SOURCE
 190
 191         # RED chain, used for the red interface
 192         iptables -N REDINPUT
 193         iptables -A INPUT -j REDINPUT
 194         iptables -N REDFORWARD
 195         iptables -A FORWARD -j REDFORWARD
 196         iptables -t nat -N REDNAT
 197         iptables -t nat -A POSTROUTING -j REDNAT
 198
 199         iptables_red
 200
 201         # Custom prerouting chains (for transparent proxy)
 202         iptables -t nat -N SQUID
 203         iptables -t nat -A PREROUTING -j SQUID
 204
 205         # DNAT rules
 206         iptables -t nat -N NAT_DESTINATION
 207         iptables -t nat -A PREROUTING -j NAT_DESTINATION
 208
 209         # upnp chain for our upnp daemon
 210         iptables -t nat -N UPNPFW
 211         iptables -t nat -A PREROUTING -j UPNPFW
 212         iptables -N UPNPFW
 213         iptables -A FORWARD -m conntrack --ctstate NEW -j UPNPFW
 214
 215         # Apply OpenVPN firewall rules
 216         /usr/local/bin/openvpnctrl --firewall-rules
 217
 218         # run wirelessctrl
 219         /usr/local/bin/wirelessctrl
 220
 221         # POLICY CHAIN
 222         iptables -N POLICYIN
 223         iptables -A INPUT -j POLICYIN
 224         iptables -N POLICYFWD
 225         iptables -A FORWARD -j POLICYFWD
 226         iptables -N POLICYOUT
 227         iptables -A OUTPUT -j POLICYOUT
 228
 229         /usr/sbin/firewall-policy
 230
 231         # read new firewall
 232         /usr/local/bin/firewallctrl
 233
 234         if [ "$DROPINPUT" == "on" ]; then
 235                 iptables -A INPUT   -m limit --limit 10/minute -j LOG --log-prefix "DROP_INPUT"
 236         fi
 237         iptables -A INPUT -j DROP -m comment --comment "DROP_INPUT"
 238         if [ "$DROPFORWARD" == "on" ]; then
 239                 iptables -A FORWARD -m limit --limit 10/minute -j LOG --log-prefix "DROP_FORWARD"
 240         fi
 241 }
 242
 243 iptables_red() {
 244         iptables -F REDINPUT
 245         iptables -F REDFORWARD
 246         iptables -t nat -F REDNAT
 247
 248         # PPPoE / PPTP Device
 249         if [ "$IFACE" != "" ]; then
 250                 # PPPoE / PPTP
 251                 if [ "$DEVICE" != "" ]; then
 252                         iptables -A REDINPUT -i $DEVICE -j ACCEPT
 253                 fi
 254                 if [ "$RED_TYPE" == "PPTP" -o "$RED_TYPE" == "PPPOE" ]; then
 255                         if [ "$RED_DEV" != "" ]; then
 256                                 iptables -A REDINPUT -i $RED_DEV -j ACCEPT
 257                         fi
 258                 fi
 259         fi
 260
 261         # PPTP over DHCP
 262         if [ "$DEVICE" != "" -a "$TYPE" == "PPTP" -a "$METHOD" == "DHCP" ]; then
 263                 iptables -A REDINPUT -p tcp --source-port 67 --destination-port 68 -i $DEVICE -j ACCEPT
 264                 iptables -A REDINPUT -p udp --source-port 67 --destination-port 68 -i $DEVICE -j ACCEPT
 265         fi
 266
 267         # Orange pinholes
 268         if [ "$ORANGE_DEV" != "" ]; then
 269                 # This rule enables a host on ORANGE network to connect to the outside
 270                 # (only if we have a red connection)
 271                 if [ "$IFACE" != "" ]; then
 272                         iptables -A REDFORWARD -i $ORANGE_DEV -o $IFACE -j ACCEPT
 273                 fi
 274         fi
 275
 276         if [ "$IFACE" != "" -a -f /var/ipfire/red/active ]; then
 277                 # DHCP
 278                 if [ "$RED_DEV" != "" -a "$RED_TYPE" == "DHCP" ]; then
 279                         iptables -A REDINPUT -p tcp --source-port 67 --destination-port 68 -i $IFACE -j ACCEPT
 280                         iptables -A REDINPUT -p udp --source-port 67 --destination-port 68 -i $IFACE -j ACCEPT
 281                 fi
 282                 if [ "$METHOD" == "DHCP"  -a "$PROTOCOL" == "RFC1483" ]; then
 283                         iptables -A REDINPUT -p tcp --source-port 67 --destination-port 68 -i $IFACE -j ACCEPT
 284                         iptables -A REDINPUT -p udp --source-port 67 --destination-port 68 -i $IFACE -j ACCEPT
 285                 fi
 286
 287                 # Outgoing masquerading (don't masqerade IPSEC (mark 50))
 288                 iptables -t nat -A REDNAT -m mark --mark 50 -o $IFACE -j RETURN
 289                 iptables -t nat -A REDNAT -o $IFACE -j MASQUERADE
 290
 291         fi
 292 }
 293
 294 # See how we were called.
 295 case "$1" in
 296   start)
 297         boot_mesg "Loading firewall modules into the kernel"
 298         modprobe iptable_nat || failed=1
 299         for i in $(find /lib/modules/$(uname -r) -name nf_conntrack*); do
 300                 modprobe $(basename $i | cut -d. -f1) || failed=1
 301         done
 302         for i in $(find /lib/modules/$(uname -r) -name nf_nat*); do
 303                 modprobe $(basename $i | cut -d. -f1) || failed=1
 304         done
 305         (exit ${failed})
 306         evaluate_retval
 307
 308         if [ -e /var/ipfire/main/disable_nf_sip ]; then
 309                 rmmod nf_nat_sip
 310                 rmmod nf_conntrack_sip
 311                 rmmod nf_nat_h323
 312                 rmmod nf_conntrack_h323
 313         fi
 314
 315         boot_mesg "Setting up firewall"
 316         iptables_init
 317         evaluate_retval
 318
 319         # run local firewall configuration, if present
 320         if [ -x /etc/sysconfig/firewall.local ]; then
 321                 /etc/sysconfig/firewall.local start
 322         fi
 323         ;;
 324   reload)
 325         boot_mesg "Reloading firewall"
 326         iptables_red
 327         evaluate_retval
 328
 329         # run local firewall configuration, if present
 330         if [ -x /etc/sysconfig/firewall.local ]; then
 331                 /etc/sysconfig/firewall.local reload
 332         fi
 333         ;;
 334   restart)
 335         # run local firewall configuration, if present
 336         if [ -x /etc/sysconfig/firewall.local ]; then
 337                 /etc/sysconfig/firewall.local stop
 338         fi
 339         $0 start
 340         ;;
 341   *)
 342         echo "Usage: $0 {start|reload|restart}"
 343         exit 1
 344         ;;
 345 esac
 346
 347 exit 0