src/initscripts/init.d/firewall

   1 #!/bin/sh
   2
   3 eval $(/usr/local/bin/readhash /var/ipfire/ppp/settings)
   4 eval $(/usr/local/bin/readhash /var/ipfire/ethernet/settings)
   5 eval $(/usr/local/bin/readhash /var/ipfire/optionsfw/settings)
   6 IFACE=`/bin/cat /var/ipfire/red/iface 2> /dev/null | /usr/bin/tr -d '\012'`
   7
   8 if [ -f /var/ipfire/red/device ]; then
   9         DEVICE=`/bin/cat /var/ipfire/red/device 2> /dev/null | /usr/bin/tr -d '\012'`
  10 fi
  11
  12 iptables_init() {
  13         # Flush all rules and delete all custom chains
  14         /sbin/iptables -F
  15         /sbin/iptables -t nat -F
  16         /sbin/iptables -t mangle -F
  17         /sbin/iptables -X
  18         /sbin/iptables -t nat -X
  19         /sbin/iptables -t mangle -X
  20
  21         # Set up policies
  22         /sbin/iptables -P INPUT DROP
  23         /sbin/iptables -P FORWARD DROP
  24         /sbin/iptables -P OUTPUT ACCEPT
  25
  26         # Empty LOG_DROP and LOG_REJECT chains
  27         /sbin/iptables -N LOG_DROP
  28         /sbin/iptables -A LOG_DROP   -m limit --limit 10/minute -j LOG
  29         /sbin/iptables -A LOG_DROP   -j DROP
  30         /sbin/iptables -N LOG_REJECT
  31         /sbin/iptables -A LOG_REJECT -m limit --limit 10/minute -j LOG
  32         /sbin/iptables -A LOG_REJECT -j REJECT
  33
  34         # This chain will log, then DROPs packets with certain bad combinations
  35         # of flags might indicate a port-scan attempt (xmas, null, etc)
  36         /sbin/iptables -N PSCAN
  37         if [ "$DROPPORTSCAN" == "on" ]; then
  38                 /sbin/iptables -A PSCAN -p tcp  -m limit --limit 10/minute -j LOG --log-prefix "DROP_TCP Scan " -m comment --comment "DROP_TCP PScan"
  39                 /sbin/iptables -A PSCAN -p udp  -m limit --limit 10/minute -j LOG --log-prefix "DROP_UDP Scan " -m comment --comment "DROP_UDP PScan"
  40                 /sbin/iptables -A PSCAN -p icmp -m limit --limit 10/minute -j LOG --log-prefix "DROP_ICMP Scan " -m comment --comment "DROP_ICMP PScan"
  41                 /sbin/iptables -A PSCAN -f      -m limit --limit 10/minute -j LOG --log-prefix "DROP_FRAG Scan " -m comment --comment "DROP_FRAG PScan"
  42         fi
  43         /sbin/iptables -A PSCAN -j DROP -m comment --comment "DROP_PScan"
  44
  45         # New tcp packets without SYN set - could well be an obscure type of port scan
  46         # that's not covered above, may just be a broken windows machine
  47         /sbin/iptables -N NEWNOTSYN
  48         if [ "$DROPNEWNOTSYN" == "on" ]; then
  49                 /sbin/iptables -A NEWNOTSYN  -m limit --limit 10/minute -j LOG  --log-prefix "DROP_NEWNOTSYN "
  50         fi
  51         /sbin/iptables -A NEWNOTSYN  -j DROP -m comment --comment "DROP_NEWNOTSYN"
  52
  53         # Chain to contain all the rules relating to bad TCP flags
  54         /sbin/iptables -N BADTCP
  55
  56         # Disallow packets frequently used by port-scanners
  57         # nmap xmas
  58         /sbin/iptables -A BADTCP -p tcp --tcp-flags ALL FIN,URG,PSH  -j PSCAN
  59         # Null
  60         /sbin/iptables -A BADTCP -p tcp --tcp-flags ALL NONE -j PSCAN
  61         # FIN
  62         /sbin/iptables -A BADTCP -p tcp --tcp-flags ALL FIN -j PSCAN
  63         # SYN/RST (also catches xmas variants that set SYN+RST+...)
  64         /sbin/iptables -A BADTCP -p tcp --tcp-flags SYN,RST SYN,RST -j PSCAN
  65         # SYN/FIN (QueSO or nmap OS probe)
  66         /sbin/iptables -A BADTCP -p tcp --tcp-flags SYN,FIN SYN,FIN -j PSCAN
  67         # NEW TCP without SYN
  68         /sbin/iptables -A BADTCP -p tcp ! --syn -m state --state NEW -j NEWNOTSYN
  69
  70         /sbin/iptables -A INPUT   -j BADTCP
  71         /sbin/iptables -A FORWARD -j BADTCP
  72
  73 }
  74
  75 iptables_red() {
  76         /sbin/iptables -F REDINPUT
  77         /sbin/iptables -F REDFORWARD
  78         /sbin/iptables -t nat -F REDNAT
  79
  80         # PPPoE / PPTP Device
  81         if [ "$IFACE" != "" ]; then
  82                 # PPPoE / PPTP
  83                 if [ "$DEVICE" != "" ]; then
  84                         /sbin/iptables -A REDINPUT -i $DEVICE -j ACCEPT
  85                 fi
  86                 if [ "$RED_TYPE" == "PPTP" -o "$RED_TYPE" == "PPPOE" ]; then
  87                         if [ "$RED_DEV" != "" ]; then
  88                                 /sbin/iptables -A REDINPUT -i $RED_DEV -j ACCEPT
  89                         fi
  90                 fi
  91         fi
  92
  93         # PPTP over DHCP
  94         if [ "$DEVICE" != "" -a "$TYPE" == "PPTP" -a "$METHOD" == "DHCP" ]; then
  95                 /sbin/iptables -A REDINPUT -p tcp --source-port 67 --destination-port 68 -i $DEVICE -j ACCEPT
  96                 /sbin/iptables -A REDINPUT -p udp --source-port 67 --destination-port 68 -i $DEVICE -j ACCEPT
  97         fi
  98
  99         # Orange pinholes
 100         if [ "$ORANGE_DEV" != "" ]; then
 101                 # This rule enables a host on ORANGE network to connect to the outside
 102                 # (only if we have a red connection)
 103                 if [ "$IFACE" != "" ]; then
 104                         /sbin/iptables -A REDFORWARD -i $ORANGE_DEV -p tcp -o $IFACE -j ACCEPT
 105                         /sbin/iptables -A REDFORWARD -i $ORANGE_DEV -p udp -o $IFACE -j ACCEPT
 106                 fi
 107         fi
 108
 109         if [ "$IFACE" != "" -a -f /var/ipfire/red/active ]; then
 110                 # DHCP
 111                 if [ "$RED_DEV" != "" -a "$RED_TYPE" == "DHCP" ]; then
 112                         /sbin/iptables -A REDINPUT -p tcp --source-port 67 --destination-port 68 -i $IFACE -j ACCEPT
 113                         /sbin/iptables -A REDINPUT -p udp --source-port 67 --destination-port 68 -i $IFACE -j ACCEPT
 114                 fi
 115                 if [ "$METHOD" == "DHCP"  -a "$PROTOCOL" == "RFC1483" ]; then
 116                         /sbin/iptables -A REDINPUT -p tcp --source-port 67 --destination-port 68 -i $IFACE -j ACCEPT
 117                         /sbin/iptables -A REDINPUT -p udp --source-port 67 --destination-port 68 -i $IFACE -j ACCEPT
 118                 fi
 119
 120                 # Outgoing masquerading
 121                 /sbin/iptables -t nat -A REDNAT -o $IFACE -j MASQUERADE
 122
 123         fi
 124 }
 125
 126 # See how we were called.
 127 case "$1" in
 128   start)
 129         iptables_init
 130
 131         # Limit Packets- helps reduce dos/syn attacks
 132         # original do nothing line
 133         #/sbin/iptables -A INPUT -p tcp -m tcp --tcp-flags SYN,RST,ACK SYN -m limit --limit 10/sec
 134         # the correct one, but the negative '!' do nothing...
 135         #/sbin/iptables -A INPUT -p tcp -m tcp --tcp-flags SYN,RST,ACK SYN -m limit ! --limit 10/sec -j DROP
 136
 137         # Fix for braindead ISP's
 138         /sbin/iptables -A FORWARD -p tcp --tcp-flags SYN,RST SYN -j TCPMSS --clamp-mss-to-pmtu
 139
 140         # CUSTOM chains, can be used by the users themselves
 141         /sbin/iptables -N CUSTOMINPUT
 142         /sbin/iptables -A INPUT -j CUSTOMINPUT
 143         /sbin/iptables -N CUSTOMFORWARD
 144         /sbin/iptables -A FORWARD -j CUSTOMFORWARD
 145         /sbin/iptables -N CUSTOMOUTPUT
 146         /sbin/iptables -A OUTPUT -j CUSTOMOUTPUT
 147         /sbin/iptables -N OUTGOINGFW
 148         /sbin/iptables -A OUTPUT -j OUTGOINGFW
 149         /sbin/iptables -t nat -N CUSTOMPREROUTING
 150         /sbin/iptables -t nat -A PREROUTING -j CUSTOMPREROUTING
 151         /sbin/iptables -t nat -N CUSTOMPOSTROUTING
 152         /sbin/iptables -t nat -A POSTROUTING -j CUSTOMPOSTROUTING
 153
 154         # filtering from GUI
 155         /sbin/iptables -N GUIINPUT
 156         /sbin/iptables -A INPUT -j GUIINPUT
 157         /sbin/iptables -A GUIINPUT -p icmp --icmp-type 8 -j ACCEPT
 158
 159         # Accept everything connected
 160         /sbin/iptables -A INPUT   -m state --state ESTABLISHED,RELATED -j ACCEPT
 161         /sbin/iptables -A FORWARD -m state --state ESTABLISHED,RELATED -j ACCEPT
 162
 163         # trafic from ipsecX/TUN/TAP interfaces, before "-i GREEN_DEV" accept everything
 164         /sbin/iptables -N IPSECVIRTUAL
 165         /sbin/iptables -N OPENSSLVIRTUAL
 166         /sbin/iptables -A INPUT -j IPSECVIRTUAL -m comment --comment "IPSECVIRTUAL INPUT"
 167         /sbin/iptables -A INPUT -j OPENSSLVIRTUAL -m comment --comment "OPENSSLVIRTUAL INPUT"
 168         /sbin/iptables -A FORWARD -j IPSECVIRTUAL -m comment --comment "IPSECVIRTUAL FORWARD"
 169         /sbin/iptables -A FORWARD -j OPENSSLVIRTUAL -m comment --comment "OPENSSLVIRTUAL FORWARD"
 170         /sbin/iptables -t nat -N IPSECPOSTROUTING
 171         /sbin/iptables -t nat -A POSTROUTING -j IPSECPOSTROUTING
 172
 173         # Outgoing Firewall
 174         /sbin/iptables -A FORWARD -j OUTGOINGFW
 175
 176         # localhost and ethernet.
 177         /sbin/iptables -A INPUT   -i lo          -m state --state NEW -j ACCEPT
 178         /sbin/iptables -A INPUT   -s 127.0.0.0/8 -m state --state NEW -j DROP   # Loopback not on lo
 179         /sbin/iptables -A INPUT   -d 127.0.0.0/8 -m state --state NEW -j DROP
 180         /sbin/iptables -A FORWARD -i lo          -m state --state NEW -j ACCEPT
 181         /sbin/iptables -A FORWARD -s 127.0.0.0/8 -m state --state NEW -j DROP
 182         /sbin/iptables -A FORWARD -d 127.0.0.0/8 -m state --state NEW -j DROP
 183         /sbin/iptables -A INPUT   -i $GREEN_DEV  -m state --state NEW -j ACCEPT -p ! icmp
 184         /sbin/iptables -A FORWARD -i $GREEN_DEV  -m state --state NEW -j ACCEPT
 185
 186         # If a host on orange tries to initiate a connection to IPFire's red IP and
 187         # the connection gets DNATed back through a port forward to a server on orange
 188         # we end up with orange -> orange traffic passing through IPFire
 189         [ "$ORANGE_DEV" != "" ] && /sbin/iptables -A FORWARD -i $ORANGE_DEV -o $ORANGE_DEV -m state --state NEW -j ACCEPT
 190
 191         # allow DHCP on BLUE to be turned on/off
 192         /sbin/iptables -N DHCPBLUEINPUT
 193         /sbin/iptables -A INPUT -j DHCPBLUEINPUT
 194
 195         # IPSec
 196         /sbin/iptables -N IPSECPHYSICAL
 197         /sbin/iptables -A INPUT -j IPSECPHYSICAL
 198
 199         # OPenSSL
 200         /sbin/iptables -N OPENSSLPHYSICAL
 201         /sbin/iptables -A INPUT -j OPENSSLPHYSICAL
 202
 203         # WIRELESS chains
 204         /sbin/iptables -N WIRELESSINPUT
 205         /sbin/iptables -A INPUT -m state --state NEW -j WIRELESSINPUT
 206         /sbin/iptables -N WIRELESSFORWARD
 207         /sbin/iptables -A FORWARD -m state --state NEW -j WIRELESSFORWARD
 208
 209         # RED chain, used for the red interface
 210         /sbin/iptables -N REDINPUT
 211         /sbin/iptables -A INPUT -j REDINPUT
 212         /sbin/iptables -N REDFORWARD
 213         /sbin/iptables -A FORWARD -j REDFORWARD
 214         /sbin/iptables -t nat -N REDNAT
 215         /sbin/iptables -t nat -A POSTROUTING -j REDNAT
 216
 217         iptables_red
 218
 219         # DMZ pinhole chain.  setdmzholes setuid prog adds rules here to allow
 220         # ORANGE to talk to GREEN / BLUE.
 221         /sbin/iptables -N DMZHOLES
 222         if [ "$ORANGE_DEV" != "" ]; then
 223                 /sbin/iptables -A FORWARD -i $ORANGE_DEV -m state --state NEW -j DMZHOLES
 224         fi
 225
 226         # XTACCESS chain, used for external access
 227         /sbin/iptables -N XTACCESS
 228         /sbin/iptables -A INPUT -m state --state NEW -j XTACCESS
 229
 230         # PORTFWACCESS chain, used for portforwarding
 231         /sbin/iptables -N PORTFWACCESS
 232         /sbin/iptables -A FORWARD -m state --state NEW -j PORTFWACCESS
 233
 234         # Custom prerouting chains (for transparent proxy and port forwarding)
 235         /sbin/iptables -t nat -N SQUID
 236         /sbin/iptables -t nat -A PREROUTING -j SQUID
 237         /sbin/iptables -t nat -N PORTFW
 238         /sbin/iptables -t nat -A PREROUTING -j PORTFW
 239
 240         # upnp chain for our upnp daemon
 241         /sbin/iptables -t nat -N UPNPFW
 242         /sbin/iptables -t nat -A PREROUTING -j UPNPFW
 243
 244
 245         # Custom mangle chain (for port fowarding)
 246         /sbin/iptables -t mangle -N PORTFWMANGLE
 247         /sbin/iptables -t mangle -A PREROUTING -j PORTFWMANGLE
 248
 249         # Postrouting rules (for port forwarding)
 250         /sbin/iptables -t nat -A POSTROUTING -m mark --mark 1 -j SNAT \
 251          --to-source $GREEN_ADDRESS
 252         if [ "$BLUE_DEV" != "" ]; then
 253                 /sbin/iptables -t nat -A POSTROUTING -m mark --mark 2 -j SNAT --to-source $BLUE_ADDRESS
 254         fi
 255         if [ "$ORANGE_DEV" != "" ]; then
 256                 /sbin/iptables -t nat -A POSTROUTING -m mark --mark 3 -j SNAT --to-source $ORANGE_ADDRESS
 257         fi
 258
 259         # run local firewall configuration, if present
 260         if [ -x /etc/sysconfig/firewall.local ]; then
 261                 /etc/sysconfig/firewall.local start
 262         fi
 263
 264         # last rule in input and forward chain is for logging.
 265
 266         if [ "$DROPINPUT" == "on" ]; then
 267                 /sbin/iptables -A INPUT -m limit --limit 10/minute -j LOG --log-prefix "DROP_INPUT "
 268         fi
 269         /sbin/iptables -A INPUT -j DROP -m comment --comment "DROP_INPUT"
 270         if [ "$DROPOUTPUT" == "on" ]; then
 271                 /sbin/iptables -A FORWARD -m limit --limit 10/minute -j LOG --log-prefix "DROP_OUTPUT "
 272         fi
 273         /sbin/iptables -A FORWARD -j DROP -m comment --comment "DROP_OUTPUT"
 274         ;;
 275   startovpn)
 276         # run openvpn
 277         /usr/local/bin/openvpnctrl --create-chains-and-rules
 278         ;;
 279   stop)
 280         iptables_init
 281         # Accept everyting connected
 282         /sbin/iptables -A INPUT   -m state --state ESTABLISHED,RELATED -j ACCEPT
 283
 284         # localhost and ethernet.
 285         /sbin/iptables -A INPUT -i lo -j ACCEPT
 286         /sbin/iptables -A INPUT -i $GREEN_DEV -m state --state NEW -j ACCEPT
 287
 288         if [ "$RED_DEV" != "" -a "$RED_TYPE" == "DHCP" ]; then
 289                 /sbin/iptables -A INPUT -p tcp --source-port 67 --destination-port 68 -i $IFACE -j ACCEPT
 290                 /sbin/iptables -A INPUT -p udp --source-port 67 --destination-port 68 -i $IFACE -j ACCEPT
 291         fi
 292         if [ "$PROTOCOL" == "RFC1483" -a "$METHOD" == "DHCP" ]; then
 293                 /sbin/iptables -A INPUT -p tcp --source-port 67 --destination-port 68 -i $IFACE -j ACCEPT
 294                 /sbin/iptables -A INPUT -p udp --source-port 67 --destination-port 68 -i $IFACE -j ACCEPT
 295         fi
 296
 297         # run local firewall configuration, if present
 298         if [ -x /etc/sysconfig/firewall.local ]; then
 299                 /etc/sysconfig/firewall.local stop
 300         fi
 301
 302         if [ "$DROPINPUT" == "on" ]; then
 303                 /sbin/iptables -A INPUT   -m limit --limit 10/minute -j LOG --log-prefix "DROP_INPUT "
 304         fi
 305         /sbin/iptables -A INPUT -j DROP -m comment --comment "DROP_INPUT"
 306         if [ "$DROPOUTPUT" == "on" ]; then
 307                 /sbin/iptables -A FORWARD -m limit --limit 10/minute -j LOG --log-prefix "DROP_OUTPUT "
 308         fi
 309         /sbin/iptables -A FORWARD -j DROP -m comment --comment "DROP_OUTPUT"
 310         ;;
 311   stopovpn)
 312         # stop openvpn
 313         /usr/local/bin/openvpnctrl --delete-chains-and-rules
 314         ;;
 315   reload)
 316         iptables_red
 317
 318         # run local firewall configuration, if present
 319         if [ -x /etc/sysconfig/firewall.local ]; then
 320                 /etc/sysconfig/firewall.local reload
 321         fi
 322         ;;
 323   restart)
 324         $0 stop
 325         $0 start
 326         ;;
 327   *)
 328         echo "Usage: $0 {start|stop|reload|restart}"
 329         exit 1
 330         ;;
 331 esac
 332
 333 exit 0