NET::HTTP behind a firewall?

[Joe Regular]

I recently deployed an app to my production server that accesses other
websites via NET::HTTP. Due to my firewall (iptables), the app is unable
to access the other sites.

What ports should I open/changes should I make to my firewall config
script (KISS) to enable ruby to make the appropriate outgoing requests?

Thanks,
Kris

 

[Jeremy Tregunna]

Outgoing connections are almost always made on high ports. It doesn't
matter what you're using to connect out, the fact that you're making
a client request to some remote server on some port, will cause your
client iport to be <ip you're going out over>:<some high port,
probably over 10000>.

So be sure you open up say 10000 - 65535 outgoing tcp

If this still doesn't work, there's probably some sort of transparent
firewall between your router and your destination blocking this.

 

[Joe Regular]

Outgoing connections are almost always made on high ports. It doesn't
matter what you're using to connect out, the fact that you're making
a client request to some remote server on some port, will cause your
client iport to be <ip you're going out over>:<some high port,
probably over 10000>.

So be sure you open up say 10000 - 65535 outgoing tcp

If this still doesn't work, there's probably some sort of transparent
firewall between your router and your destination blocking this.

Jeremy, thanks for the help. I knew the outgoing connections were made
on higher ports but I was not sure which range of ports they would be
made on and I wanted to keep my config as tight as possible. I also
wanted to know if there was a way to allow a specific process (such as
the one running ruby) to access all outgoing ports.

Francis, thanks for your support.

 

[Jeremy Tregunna]

Jeremy, thanks for the help. I knew the outgoing connections were made
on higher ports but I was not sure which range of ports they would be
made on and I wanted to keep my config as tight as possible. I also
wanted to know if there was a way to allow a specific process (such as
the one running ruby) to access all outgoing ports.

I'm not familiar with iptables, so I cannot tell you. But considering
that for instance, OpenBSD's pf allows you to specify user, I would
be shocked if iptables hasn't copied that idea.

 

[Joe Regular]

Jeremy, thanks for the help. I knew the outgoing connections were made
on higher ports but I was not sure which range of ports they would be
made on and I wanted to keep my config as tight as possible. I also
wanted to know if there was a way to allow a specific process (such as
the one running ruby) to access all outgoing ports.

Francis, thanks for your support.

Francis, I do not know much about iptables so I am using the KISS script
to manage iptables. I am not that stupid and have obviously tried to
open 80 and 443. I suppose I could read more about configuring iptables
manually but KISS has worked fine for all the other applications I am
running for a year and I would rather stick with it. If you don't mind,
I would appreciate it if you could tell me if their is a problem with
KISS config that is causing iptables to constrain outbound traffic based
on the local port. Here is my kiss config...

#!/bin/bash
#
# http://www.geocities.com/steve93138/
#
#

##############################################################################
#
# Optional KISS Configurtion Variables:
#
BLOCK_LIST=""
TCP_IN="20 21 25 53 80 110 143 443 995 3306 8443 10000 19638"
TCP_OUT="21 22 25 37 43 53 80 443 55000"
UDP_IN="53"
UDP_OUT="53"
TCP_IN_TRUSTED="22"
TRUSTED_IPS="0.0.0.0/0"
SERVER_IPS="0.0.0.0/0"

##############################################################################
#
PUB_IFACE="eth1"
PRIV_IFACE="eth0"

#####
# Please note that only the PRIVATE_IP needs to be found as PUB_IFACE
# IP is detected in the MAIN_IP variable below.
#####
if [ ! "$PRIV_IFACE" == "" ]; then
PRIVATE_IP=`ifconfig $PRIV_IFACE | grep "inet addr" | cut -d: -f2 | awk
'{print $1}'`
fi


##############################################################################
#
# ALL DONE WITH CONFIGURATIONS!
#
# No real need to modify anything for the remainder of this file except
to
# maybe remove the comments from certains lines at the end of this file.
#

# Some variables here. Modify if needed for your system.
IPTABLES="/sbin/iptables"
MODPROBE="/sbin/modprobe"
LOOPBACK="127.0.0.0/8"
CLASS_A="10.0.0.0/8"
CLASS_B="172.16.0.0/12"
CLASS_C="192.168.0.0/16"
CLASS_D_MULTICAST="224.0.0.0/4"
CLASS_E_RESERVED_NET="240.0.0.0/4"
BROADCAST_SRC="0.0.0.0"
BROADCAST_DEST="255.255.255.255"
PRIVPORTS="0:1023"
UNPRIVPORTS="1024:65535"


##############################################################################
# Determine if iptables and modprobe exist
#
if [ ! -e "$IPTABLES" ]; then
echo "$IPTABLES does not exist. Firewall script aborted!"
exit 1
fi
if [ ! -e "$MODPROBE" ]; then
echo "$MODPROBE does not exist. Firewall script aborted!"
exit 1
fi


##############################################################################
# Determine MAIN_IP & SERVER_IPS if needed
#
MAIN_IP=`ifconfig $PUB_IFACE | grep "inet addr" | cut -d: -f2 | awk
'{print $1}'`
if [ "$MAIN_IP" == "" ]; then
echo "Could not determine MAIN_IP. Firewall script aborted!"
exit 1
fi
if [ "$SERVER_IPS" == "" ]; then
SERVER_IPS=$MAIN_IP
fi
if [ "$SERVER_IPS" == "" ]; then
echo "Could not determine SERVER_IPS. Firewall script aborted!"
exit 1
fi


##############################################################################

# Arguments:
if [ "$1" == "stop" ] || [ "$1" == "-stop" ] || [ "$1" == "--stop" ];
then
$IPTABLES -P INPUT ACCEPT
$IPTABLES -P OUTPUT ACCEPT
$IPTABLES -F
$IPTABLES -L -n
echo ""
echo ""
echo -e "\033[31mKISS My Firewall - Stopped!"
echo -e -n "\033[0m "
echo ""
exit 0
fi
if [ "$1" == "status" ] || [ "$1" == "-status" ] || [ "$1" == "--status"
]; then
NUM_LINES=`$IPTABLES -L -n | wc -l | awk '{print $1}'`
$IPTABLES -L -n
echo ""
echo ""
if [ "$NUM_LINES" -le "15" ]; then
echo -e "\033[31mKISS My Firewall - Stopped!"
else
echo -e "\033[32mKISS My Firewall - Running!"
fi
echo -e -n "\033[0m "
echo ""
exit 0
fi


##############################################################################

# We don't want ipchains loaded:
IPCHAINS=`/sbin/lsmod | grep ipchains`
if [ ! "$IPCHAINS" == "" ]; then
/sbin/rmmod ipchains
fi



##############################################################################

# Note: KISS requires that ip_tables, ipt_state, and ipt_multiport
exist:
if [ ! -e "/lib/modules/$(uname
-r)/kernel/net/ipv4/netfilter/ip_tables.ko" ] || [ ! -e
"/lib/modules/$(uname -r)/kernel/net/ipv4/netfilter/ipt_state.ko" ] || [
! -e "/lib/modules/$(uname
-r)/kernel/net/ipv4/netfilter/ipt_multiport.ko" ]; then
echo "Since the ip_tables, ipt_state, and/or ipt_multiport modules
do not exist, KISS can not function. Firewall script aborted!"
exit 1
fi

# All is well, load modules:
if [ -e "/lib/modules/$(uname
-r)/kernel/net/ipv4/netfilter/ip_tables.ko" ]; then
$MODPROBE ip_tables
fi
if [ -e "/lib/modules/$(uname
-r)/kernel/net/ipv4/netfilter/ipt_state.ko" ]; then
$MODPROBE ipt_state
fi
if [ -e "/lib/modules/$(uname
-r)/kernel/net/ipv4/netfilter/ipt_multiport.ko" ]; then
$MODPROBE ipt_multiport
fi
if [ -e "/lib/modules/$(uname
-r)/kernel/net/ipv4/netfilter/ip_tables.ko" ]; then
$MODPROBE ip_tables
fi
if [ -e "/lib/modules/$(uname
-r)/kernel/net/ipv4/netfilter/ipt_state.ko" ]; then
$MODPROBE ipt_state
fi
if [ -e "/lib/modules/$(uname
-r)/kernel/net/ipv4/netfilter/ipt_multiport.ko" ]; then
$MODPROBE ipt_multiport
fi
if [ -e "/lib/modules/$(uname
-r)/kernel/net/ipv4/netfilter/iptable_filter.ko" ]; then
$MODPROBE iptable_filter
fi
if [ -e "/lib/modules/$(uname
-r)/kernel/net/ipv4/netfilter/ipt_unclean.ko" ]; then
$MODPROBE ipt_unclean
fi
if [ -e "/lib/modules/$(uname
-r)/kernel/net/ipv4/netfilter/ipt_limit.ko" ]; then
$MODPROBE ipt_limit
fi
if [ -e "/lib/modules/$(uname -r)/kernel/net/ipv4/netfilter/ipt_LOG.ko"
]; then
$MODPROBE ipt_LOG
fi
if [ -e "/lib/modules/$(uname
-r)/kernel/net/ipv4/netfilter/ipt_REJECT.ko" ]; then
$MODPROBE ipt_REJECT
fi
if [ -e "/lib/modules/$(uname
-r)/kernel/net/ipv4/netfilter/ip_conntrack.ko" ]; then
$MODPROBE ip_conntrack
fi
if [ -e "/lib/modules/$(uname
-r)/kernel/net/ipv4/netfilter/ip_conntrack_irc.ko" ]; then
$MODPROBE ip_conntrack_irc
fi
if [ -e "/lib/modules/$(uname
-r)/kernel/net/ipv4/netfilter/ip_conntrack_ftp.ko" ]; then
$MODPROBE ip_conntrack_ftp
fi
if [ -e "/lib/modules/$(uname
-r)/kernel/net/ipv4/netfilter/iptable_mangle.ko" ]; then
$MODPROBE iptable_mangle
fi


##############################################################################

# Remove any existing rules from all chains
$IPTABLES --flush
$IPTABLES -t nat --flush
$IPTABLES -t mangle --flush

# Allow unlimited traffic on the loopback interface
$IPTABLES -A INPUT -i lo -j ACCEPT
$IPTABLES -A OUTPUT -o lo -j ACCEPT

# Set the default policy to DROP
$IPTABLES --policy INPUT DROP
$IPTABLES --policy OUTPUT DROP
$IPTABLES --policy FORWARD DROP

# DO NOT MODIFY THESE!
#
# If you set these to DROP, you will be locked out of your server.
#
$IPTABLES -t nat --policy PREROUTING ACCEPT
$IPTABLES -t nat --policy OUTPUT ACCEPT
$IPTABLES -t nat --policy POSTROUTING ACCEPT
$IPTABLES -t mangle --policy PREROUTING ACCEPT
$IPTABLES -t mangle --policy OUTPUT ACCEPT

# Remove any pre-existing user-defined chains
$IPTABLES --delete-chain
$IPTABLES -t nat --delete-chain
$IPTABLES -t mangle --delete-chain


##############################################################################

# Enable broadcast echo Protection
if [ -e /proc/sys/net/ipv4/icmp_echo_ignore_broadcasts ]; then
echo "1" > /proc/sys/net/ipv4/icmp_echo_ignore_broadcasts
fi

# Disable Source Routed Packets
if [ -e /proc/sys/net/ipv4/conf/all/accept_source_route ]; then
echo "0" > /proc/sys/net/ipv4/conf/all/accept_source_route
fi

# Enable TCP SYN Cookie Protection
if [ -e /proc/sys/net/ipv4/tcp_syncookies ]; then
echo "1" > /proc/sys/net/ipv4/tcp_syncookies
fi

# Disable ICMP Redirect Acceptance
if [ -e /proc/sys/net/ipv4/conf/all/accept_redirects ]; then
echo "0" > /proc/sys/net/ipv4/conf/all/accept_redirects
fi

# Don't send Redirect Messages
if [ -e /proc/sys/net/ipv4/conf/all/send_redirects ]; then
echo "0" > /proc/sys/net/ipv4/conf/all/send_redirects
fi


# Drop Spoofed Packets coming in on an interface, which if replied to,
would
# result in the reply going out a different interface.
if [ -e /proc/sys/net/ipv4/conf/all/rp_filter ]; then
echo "1" > /proc/sys/net/ipv4/conf/all/rp_filter
fi

# Log packets with impossible addresses
if [ -e /proc/sys/net/ipv4/conf/all/log_martians ]; then
echo "1" > /proc/sys/net/ipv4/conf/all/log_martians
fi


# Reduce DoS'ing ability by reducing timeouts
if [ -e /proc/sys/net/ipv4/tcp_fin_timeout ]; then
echo "1800" > /proc/sys/net/ipv4/tcp_fin_timeout
fi
if [ -e /proc/sys/net/ipv4/tcp_keepalive_time ]; then
echo "1800" > /proc/sys/net/ipv4/tcp_keepalive_time
fi
if [ -e /proc/sys/net/ipv4/tcp_window_scaling ]; then
echo "0" > /proc/sys/net/ipv4/tcp_window_scaling
fi
if [ -e /proc/sys/net/ipv4/tcp_sack ]; then
echo "0" > /proc/sys/net/ipv4/tcp_sack
fi


##############################################################################
# Silently Drop Stealth Scans

# All of the bits are cleared
$IPTABLES -A INPUT -p tcp --tcp-flags ALL NONE -j DROP

# SYN and FIN are both set
$IPTABLES -A INPUT -p tcp --tcp-flags SYN,FIN SYN,FIN -j DROP

# SYN and RST are both set
$IPTABLES -A INPUT -p tcp --tcp-flags SYN,RST SYN,RST -j DROP

# FIN and RST are both set
$IPTABLES -A INPUT -p tcp --tcp-flags FIN,RST FIN,RST -j DROP

# FIN is the only bit set, without the expected accompanying ACK
$IPTABLES -A INPUT -p tcp --tcp-flags ACK,FIN FIN -j DROP

# PSH is the only bit set, without the expected accompanying ACK
$IPTABLES -A INPUT -p tcp --tcp-flags ACK,PSH PSH -j DROP

# URG is the only bit set, without the expected accompanying ACK
$IPTABLES -A INPUT -p tcp --tcp-flags ACK,URG URG -j DROP


##############################################################################
# Provide some syn-flood protection
#
# THIS CODE SLOWS DOWN WEB PAGE LOADS DRAMATICALLY!!!
#
# Only enable this code if you find that you are the victim of a
syn-flood
# attack!
#
#$IPTABLES -N syn-flood
#$IPTABLES -A INPUT -p tcp --syn -j syn-flood
#$IPTABLES -A syn-flood -m limit --limit 1/s --limit-burst 4 -j RETURN
#$IPTABLES -A syn-flood -j DROP
#


##############################################################################
# BLOCK_LIST
#
# To add someone to this block list, use the BLOCK_LIST configuration
variable
# above.
#
# We block here, before our stateful packet inspection below, because if
the
# offender is already logged in, he won't be kicked out. Note also that
we
# include the offender's IP in the OUTPUT chain. This should help to
reduce
# the threat a little bit more.
#
for blocked_ip in $BLOCK_LIST; do
# Lock him out:
$IPTABLES -A INPUT -s $blocked_ip -j DROP
# Make sure that he never hears from us again:
$IPTABLES -A OUTPUT -d $blocked_ip -j DROP
done

##############################################################################
#
# To define your private network, use the PRIV_IFACE configuration
# variable above.
#
# We allow all traffic in and out of the private network
if [ ! "$PRIV_IFACE" == ""]; then
$IPTABLES -A INPUT -s 0/0 -e $PRIV_IFACE -d $PRIVATE_IP -p ALL -j
ACCEPT
fi

##############################################################################
# Use Connection State to Bypass Rule Checking
#
# By accepting established and related connections, we don't need to
# explicitly set various input and output rules. For example, by
accepting an
# established and related output connection, we don't need to specify
that
# the firewall needs to open a hole back out to client when the client
# requests SSH access.
#
$IPTABLES -A INPUT -m state --state ESTABLISHED,RELATED -j ACCEPT
$IPTABLES -A OUTPUT -m state --state ESTABLISHED,RELATED -j ACCEPT

$IPTABLES -A INPUT -m state --state INVALID -j DROP
$IPTABLES -A OUTPUT -m state --state INVALID -j DROP


##############################################################################
# Source Address Spoofing and Other Bad Addresses

# Refuse Spoofed packets pretending to be from the external interface's
IP
#for server_ips in $SERVER_IPS; do
# $IPTABLES -A INPUT -i $PUB_IFACE -s $server_ips -j DROP
#done
#for server_ips in $SERVER_IPS; do
# for subnet_broadcast in $SUBNET_BROADCAST; do
# $IPTABLES -A INPUT -i $PUB_IFACE -s $server_ips -d
!$subnet_broadcast -j DROP
# done
#done

# Refuse packets claiming to be from a Class A private network
$IPTABLES -A INPUT -i $PUB_IFACE -s $CLASS_A -j DROP

# Refuse packets claiming to be from a Class B private network
$IPTABLES -A INPUT -i $PUB_IFACE -s $CLASS_B -j DROP

# Refuse packets claiming to be from a Class C private network
#$IPTABLES -A INPUT -i $PUB_IFACE -s $CLASS_C -j DROP

# Refuse packets claiming to be from the loopback interface
$IPTABLES -A INPUT -i $PUB_IFACE -s $LOOPBACK -j DROP

# Refuse malformed broadcast packets
$IPTABLES -A INPUT -i $PUB_IFACE -s $BROADCAST_DEST -j DROP
$IPTABLES -A INPUT -i $PUB_IFACE -d $BROADCAST_SRC -j DROP

# Refuse directed broadcasts
# Used to map networks and in Denial of Service attacks
#for subnet_base in $SUBNET_BASE; do
# $IPTABLES -A INPUT -i $PUB_IFACE -d $subnet_base -j DROP
#done
#for subnet_broadcast in $SUBNET_BROADCAST; do
# $IPTABLES -A INPUT -i $PUB_IFACE -d $subnet_broadcast -j DROP
#done

# Refuse limited broadcasts
$IPTABLES -A INPUT -i $PUB_IFACE -d $BROADCAST_DEST -j DROP

# Refuse Class D multicast addresses - illegal as a source address
#$IPTABLES -A INPUT -i $PUB_IFACE -s $CLASS_D_MULTICAST -j DROP
#$IPTABLES -A INPUT -i $PUB_IFACE -p ! udp -d $CLASS_D_MULTICAST -j DROP
#$IPTABLES -A INPUT -i $PUB_IFACE -p udp -d $CLASS_D_MULTICAST -j ACCEPT
#
$IPTABLES -A INPUT -i $PUB_IFACE -s $CLASS_D_MULTICAST -j DROP
$IPTABLES -A INPUT -i $PUB_IFACE -p udp -d $CLASS_D_MULTICAST -j ACCEPT
$IPTABLES -A INPUT -i $PUB_IFACE -p 2 -d $CLASS_D_MULTICAST -j ACCEPT
$IPTABLES -A INPUT -i $PUB_IFACE -p all -d $CLASS_D_MULTICAST -j DROP


# Refuse Class E reserved IP addresses
$IPTABLES -A INPUT -i $PUB_IFACE -s $CLASS_E_RESERVED_NET -j DROP

# Refuse addresses defined as reserved by the IANA
# 0.*.*.* - Can't be blocked unilaterally with DHCP
# 169.254.0.0/16 - Link Local Networks
# 192.0.2.0/24 - TEST-NET
$IPTABLES -A INPUT -i $PUB_IFACE -s 0.0.0.0/8 -j DROP
$IPTABLES -A INPUT -i $PUB_IFACE -s 169.254.0.0/16 -j DROP
$IPTABLES -A INPUT -i $PUB_IFACE -s 192.0.2.0/24 -j DROP



##############################################################################
# Now we can open up some holes in our firewall...
#


##############################################################################
# If we are not accepting 113 (ident), then we explicitly reject it!
#
if [ "$(echo $IN_PORTS | tr ',' '\n' | grep -w 113)" == "" ]; then
$IPTABLES -A INPUT -p tcp -s 0/0 -d 0/0 --dport 113 -j REJECT
$IPTABLES -A INPUT -p udp -s 0/0 -d 0/0 --dport 113 -j REJECT
fi


##############################################################################
# TCP IN
#
for tcp_in in $TCP_IN; do
for server_ips in $SERVER_IPS; do
$IPTABLES -A INPUT -i $PUB_IFACE -s 0/0 -d $server_ips -p tcp -m
state --state NEW --sport $UNPRIVPORTS --dport $tcp_in -j ACCEPT
done
done

##############################################################################
# TCP OUT
#
for tcp_out in $TCP_OUT; do
$IPTABLES -A OUTPUT -o $PUB_IFACE -p tcp -m state --state NEW
--sport $UNPRIVPORTS --dport $tcp_out -j ACCEPT
done

##############################################################################
# UDP IN
#
for udp_in in $UDP_IN; do
for server_ips in $SERVER_IPS; do
$IPTABLES -A INPUT -i $PUB_IFACE -s 0/0 -d $server_ips -p udp -m
state --state NEW --sport $UNPRIVPORTS --dport $udp_in -j ACCEPT
done
done

##############################################################################
# UDP OUT
#
for udp_out in $UDP_OUT; do
$IPTABLES -A OUTPUT -o $PUB_IFACE -p udp -m state --state NEW
--sport $UNPRIVPORTS --dport $udp_out -j ACCEPT
done

##############################################################################
# TCP IN TRUSTED
#
#for tcp_in_trusted in $TCP_IN_TRUSTED; do
# for server_ips in $SERVER_IPS; do
# for trusted_ips in $TRUSTED_IPS; do
# $IPTABLES -A INPUT -i $PUB_IFACE -s $trusted_ips -d
$server_ips -p tcp -m state --state NEW --sport $UNPRIVPORTS --dport
$tcp_in_trusted -j ACCEPT
# done
# done
#done
for tcp_in_trusted in $TCP_IN_TRUSTED; do
for trusted_ips in $TRUSTED_IPS; do
$IPTABLES -A INPUT -i $PUB_IFACE -s $trusted_ips -d $MAIN_IP -p
tcp -m state --state NEW --sport $UNPRIVPORTS --dport $tcp_in_trusted -j
ACCEPT
done
done


##############################################################################
# Allow pinging of this server's MAIN_IP by trusted IPs only.
#
for trusted_ips in $TRUSTED_IPS; do
$IPTABLES -A INPUT -s $trusted_ips -d $MAIN_IP -i $PUB_IFACE -m
state --state NEW -p icmp --icmp-type ping -j ACCEPT
done


##############################################################################
# OUTPUT - PORT 113 - IDENTD
#
#for server_ips in $SERVER_IPS; do
# $IPTABLES -A OUTPUT -o $PUB_IFACE -s $server_ips -p tcp --syn --sport
$UNPRIVPORTS --dport 113 -m state --state NEW -j REJECT --reject-with
tcp-reset
#done


##############################################################################
# Uncomment to allow DNS zone transfers
#
$IPTABLES -A INPUT -i $PUB_IFACE -p udp --sport 53 --dport 53 -m state
--state NEW -j ACCEPT
$IPTABLES -A INPUT -i $PUB_IFACE -p tcp --sport 53 --dport 53 -m state
--state NEW -j ACCEPT
$IPTABLES -A OUTPUT -o $PUB_IFACE -p udp --sport 53 --dport 53 -m state
--state NEW -j ACCEPT
$IPTABLES -A OUTPUT -o $PUB_IFACE -p tcp --sport 53 --dport 53 -m state
--state NEW -j ACCEPT


##############################################################################
# Uncomment to allow for outgoing ping
#
#$IPTABLES -A OUTPUT -o $PUB_IFACE -s $MAIN_IP -m state --state NEW -p
icmp --icmp-type ping -j ACCEPT


##############################################################################
# Uncomment to allow outgoing traceroutes
#
#$IPTABLES -A OUTPUT -o $PUB_IFACE -p udp -s $MAIN_IP --sport
32769:65535 --dport 33434:33523 -m state --state NEW -j ACCEPT

$IPTABLES -L -n
echo ""
echo ""
echo -e "\033[32mKISS My Firewall - Running!"
echo -e -n "\033[0m "
echo ""

exit 0

 

[Joe Regular]

Yes, eth1 is the public nic. I can not ping anything with the firewall
enabled. I can access all the tcp_in ports from external machines.
tracert is not working on my workstation right now, it times out to any
host on the second hop.

My code works properly on my workstations, development servers, and even
the production server without the firewall config enabled.

Is it possible that NET:HTTP is attempting to use a local port that is
lower than NPRIVPORTS allows?

Thanks for your help Francis.

Thanks,
Kris

 

[Joe Regular]

and here is the output of iptables -L...


Chain INPUT (policy DROP)
target prot opt source destination
ACCEPT all -- anywhere anywhere
DROP tcp -- anywhere anywhere tcp
flags:FIN,SYN,R
ST,PSH,ACK,URG/NONE
DROP tcp -- anywhere anywhere tcp
flags:FIN,SYN/F
IN,SYN
DROP tcp -- anywhere anywhere tcp
flags:SYN,RST/S
YN,RST
DROP tcp -- anywhere anywhere tcp
flags:FIN,RST/F
IN,RST
DROP tcp -- anywhere anywhere tcp
flags:FIN,ACK/F
IN
DROP tcp -- anywhere anywhere tcp
flagsSH,ACK/P
SH
DROP tcp -- anywhere anywhere tcp
flags:ACK,URG/U
RG
ACCEPT all -- anywhere anywhere state
RELATED,ESTAB
LISHED
DROP all -- anywhere anywhere state
INVALID
DROP all -- 10.0.0.0/8 anywhere
DROP all -- 172.16.0.0/12 anywhere
DROP all -- 127.0.0.0/8 anywhere
DROP all -- 255.255.255.255 anywhere
DROP all -- anywhere 0.0.0.0
DROP all -- anywhere 255.255.255.255
DROP all -- 224.0.0.0/4 anywhere
ACCEPT udp -- anywhere 224.0.0.0/4
ACCEPT igmp -- anywhere 224.0.0.0/4
DROP all -- anywhere 224.0.0.0/4
DROP all -- 240.0.0.0/4 anywhere
DROP all -- 0.0.0.0/8 anywhere
DROP all -- 169.254.0.0/16 anywhere
DROP all -- 192.0.2.0/24 anywhere
REJECT tcp -- anywhere anywhere tcp
dpt:auth reject
-with icmp-port-unreachable
REJECT udp -- anywhere anywhere udp
dpt:auth reject
-with icmp-port-unreachable
ACCEPT tcp -- anywhere anywhere state NEW
tcp spts:
1024:65535 dpt:ftp-data
ACCEPT tcp -- anywhere anywhere state NEW
tcp spts:
1024:65535 dpt:ftp
ACCEPT tcp -- anywhere anywhere state NEW
tcp spts:
1024:65535 dpt:smtp
ACCEPT tcp -- anywhere anywhere state NEW
tcp spts:
1024:65535 dpt:domain
ACCEPT tcp -- anywhere anywhere state NEW
tcp spts:
1024:65535 dpt:http
ACCEPT tcp -- anywhere anywhere state NEW
tcp spts:
1024:65535 dptop3
ACCEPT tcp -- anywhere anywhere state NEW
tcp spts:
1024:65535 dpt:imap
ACCEPT tcp -- anywhere anywhere state NEW
tcp spts:
1024:65535 dpt:https
ACCEPT tcp -- anywhere anywhere state NEW
tcp spts:
1024:65535 dptop3s
ACCEPT tcp -- anywhere anywhere state NEW
tcp spts:
1024:65535 dpt:mysql
ACCEPT tcp -- anywhere anywhere state NEW
tcp spts:
1024:65535 dpt:8443
ACCEPT tcp -- anywhere anywhere state NEW
tcp spts:
1024:65535 dpt:10000
ACCEPT tcp -- anywhere anywhere state NEW
tcp spts:
1024:65535 dpt:19638
ACCEPT udp -- anywhere anywhere state NEW
udp spts:
1024:65535 dpt:domain
ACCEPT tcp -- anywhere **mydomain*** state NEW tcp
spts:
1024:65535 dpt:ssh
ACCEPT icmp -- anywhere **mydomain*** state NEW icmp
echo
-request
ACCEPT udp -- anywhere anywhere udp
spt:domain dpt:
domain state NEW
ACCEPT tcp -- anywhere anywhere tcp
spt:domain dpt:
domain state NEW

Chain FORWARD (policy DROP)
target prot opt source destination

Chain OUTPUT (policy DROP)
target prot opt source destination
ACCEPT all -- anywhere anywhere
ACCEPT all -- anywhere anywhere state
RELATED,ESTAB
LISHED
DROP all -- anywhere anywhere state
INVALID
ACCEPT tcp -- anywhere anywhere state NEW
tcp spts:
1024:65535 dpt:ftp
ACCEPT tcp -- anywhere anywhere state NEW
tcp spts:
1024:65535 dpt:ssh
ACCEPT tcp -- anywhere anywhere state NEW
tcp spts:
1024:65535 dpt:smtp
ACCEPT tcp -- anywhere anywhere state NEW
tcp spts:
1024:65535 dpt:time
ACCEPT tcp -- anywhere anywhere state NEW
tcp spts:
1024:65535 dpt:nicname
ACCEPT tcp -- anywhere anywhere state NEW
tcp spts:
1024:65535 dpt:domain
ACCEPT tcp -- anywhere anywhere state NEW
tcp spts:
1024:65535 dpt:http
ACCEPT tcp -- anywhere anywhere state NEW
tcp spts:
1024:65535 dpt:https
ACCEPT tcp -- anywhere anywhere state NEW
tcp spts:
1024:65535 dpt:55000
ACCEPT udp -- anywhere anywhere state NEW
udp spts:
1024:65535 dpt:domain
ACCEPT udp -- anywhere anywhere udp
spt:domain dpt:
domain state NEW
ACCEPT tcp -- anywhere anywhere tcp
spt:domain dpt:
domain state NEW
[root@ptp1 ~]# iptables -L
Chain INPUT (policy DROP)
target prot opt source destination
ACCEPT all -- anywhere anywhere
DROP tcp -- anywhere anywhere tcp
flags:FIN,SYN,RST,PSH,ACK,URG/NONE
DROP tcp -- anywhere anywhere tcp
flags:FIN,SYN/FIN,SYN
DROP tcp -- anywhere anywhere tcp
flags:SYN,RST/SYN,RST
DROP tcp -- anywhere anywhere tcp
flags:FIN,RST/FIN,RST
DROP tcp -- anywhere anywhere tcp
flags:FIN,ACK/FIN
DROP tcp -- anywhere anywhere tcp
flagsSH,ACK/PSH
DROP tcp -- anywhere anywhere tcp
flags:ACK,URG/URG
ACCEPT all -- anywhere anywhere state
RELATED,ESTABLISHED
DROP all -- anywhere anywhere state
INVALID
DROP all -- 10.0.0.0/8 anywhere
DROP all -- 172.16.0.0/12 anywhere
DROP all -- 127.0.0.0/8 anywhere
DROP all -- 255.255.255.255 anywhere
DROP all -- anywhere 0.0.0.0
DROP all -- anywhere 255.255.255.255
DROP all -- 224.0.0.0/4 anywhere
ACCEPT udp -- anywhere 224.0.0.0/4
ACCEPT igmp -- anywhere 224.0.0.0/4
DROP all -- anywhere 224.0.0.0/4
DROP all -- 240.0.0.0/4 anywhere
DROP all -- 0.0.0.0/8 anywhere
DROP all -- 169.254.0.0/16 anywhere
DROP all -- 192.0.2.0/24 anywhere
REJECT tcp -- anywhere anywhere tcp
dpt:auth reject-with icmp-port-unreachable
REJECT udp -- anywhere anywhere udp
dpt:auth reject-with icmp-port-unreachable
ACCEPT tcp -- anywhere anywhere state NEW
tcp spts:1024:65535 dpt:ftp-data
ACCEPT tcp -- anywhere anywhere state NEW
tcp spts:1024:65535 dpt:ftp
ACCEPT tcp -- anywhere anywhere state NEW
tcp spts:1024:65535 dpt:smtp
ACCEPT tcp -- anywhere anywhere state NEW
tcp spts:1024:65535 dpt:domain
ACCEPT tcp -- anywhere anywhere state NEW
tcp spts:1024:65535 dpt:http
ACCEPT tcp -- anywhere anywhere state NEW
tcp spts:1024:65535 dptop3
ACCEPT tcp -- anywhere anywhere state NEW
tcp spts:1024:65535 dpt:imap
ACCEPT tcp -- anywhere anywhere state NEW
tcp spts:1024:65535 dpt:https
ACCEPT tcp -- anywhere anywhere state NEW
tcp spts:1024:65535 dptop3s
ACCEPT tcp -- anywhere anywhere state NEW
tcp spts:1024:65535 dpt:mysql
ACCEPT tcp -- anywhere anywhere state NEW
tcp spts:1024:65535 dpt:8443
ACCEPT tcp -- anywhere anywhere state NEW
tcp spts:1024:65535 dpt:10000
ACCEPT tcp -- anywhere anywhere state NEW
tcp spts:1024:65535 dpt:19638
ACCEPT udp -- anywhere anywhere state NEW
udp spts:1024:65535 dpt:domain
ACCEPT tcp -- anywhere **mydomain** state NEW tcp
spts:1024:65535 dpt:ssh
ACCEPT icmp -- anywhere **mydomain** state NEW icmp
echo-request
ACCEPT udp -- anywhere anywhere udp
spt:domain dpt:domain state NEW
ACCEPT tcp -- anywhere anywhere tcp
spt:domain dpt:domain state NEW

Chain FORWARD (policy DROP)
target prot opt source destination

Chain OUTPUT (policy DROP)
target prot opt source destination
ACCEPT all -- anywhere anywhere
ACCEPT all -- anywhere anywhere state
RELATED,ESTABLISHED
DROP all -- anywhere anywhere state
INVALID
ACCEPT tcp -- anywhere anywhere state NEW
tcp spts:1024:65535 dpt:ftp
ACCEPT tcp -- anywhere anywhere state NEW
tcp spts:1024:65535 dpt:ssh
ACCEPT tcp -- anywhere anywhere state NEW
tcp spts:1024:65535 dpt:smtp
ACCEPT tcp -- anywhere anywhere state NEW
tcp spts:1024:65535 dpt:time
ACCEPT tcp -- anywhere anywhere state NEW
tcp spts:1024:65535 dpt:nicname
ACCEPT tcp -- anywhere anywhere state NEW
tcp spts:1024:65535 dpt:domain
ACCEPT tcp -- anywhere anywhere state NEW
tcp spts:1024:65535 dpt:http
ACCEPT tcp -- anywhere anywhere state NEW
tcp spts:1024:65535 dpt:https
ACCEPT tcp -- anywhere anywhere state NEW
tcp spts:1024:65535 dpt:55000
ACCEPT udp -- anywhere anywhere state NEW
udp spts:1024:65535 dpt:domain
ACCEPT udp -- anywhere anywhere udp
spt:domain dpt:domain state NEW
ACCEPT tcp -- anywhere anywhere tcp
spt:domain dpt:domain state NEW

 

[ruby grl]

I was hosting with site5 but their support was terrible I finally had to
cancel service, they never responded to support questions. I finally spent
some money a dedicated host running rails on suse linux with redplaid
hosting and it has been so much more reliable.

 

[Joe Regular]

Not sure what is going on with this thread but hopefully this post makes
it to the correct location...

I checked the logs and all it says is basically that NET::HTTP cannot
resolve the host, so there isn't enough information to figure out
exactly why the connection is failing. I will give the SYN flag a try
and also look into understanding iptables on my own without the KISS
script. Thanks again for your help.

 

[Joe Regular]

I tried removing the SYN rules and various other ones with no luck. I
also tried allowing all outgoing ports above 10000 with no luck. However
when I allowed outgoing ports below 10000 it worked. Not sure why yet
but I will attempt to figure out the exact port it needs a little later.

 

[Amos King]

This site has a one free year deal that I used. It works great and
after your ap is running if you need more space or bandwidth you can
always upgrade. Every time I've sent their support an e-mail I get a
response that day. They truly are a good hosting company.


http://www.hostingrails.com/home/112330218

 

[James Cribbs]

I highly recommend Rails Playground. Joe Clarke has responded to every
email request I have sent in a timely, courteous manner. Once, on a
Sunday afternoon, I sent a request to install a gem. Within a couple of
hours, Joe responded saying it was it done. On a Sunday!

That's just one example of the outstanding customer service I have
received from Rails Playground.

Jamey Cribbs

 

[Joe Regular]

Hi Francis,

Thanks, it turns out that my previous fix was only temporary which made
me realize that this actually is a problem with DNS since it was
probably caching the host lookups and that is why it works for a little
while.

I can not do a dig when the firewall is active(just hangs). However, my
external DNS servers appear to be ips on my private network and it looks
like there is a rule in my config to allow all traffic/protocals across
eth0(private nic) so I am not sure what is going on. I also have port 53
open to tcp/udp on both devices.

Thanks again for all your help.

Thanks,
Kris

 

[Joe Regular]

I beleive this rule should enable me to reach the DNS servers from eth0
since PRIV_IFACE is set to eth0. Do you see anything wrong with it?

##############################################################################
#
# To define your private network, use the PRIV_IFACE configuration
# variable above.
#
# We allow all traffic in and out of the private network
if [ ! "$PRIV_IFACE" == ""]; then
$IPTABLES -A INPUT -s 0/0 -e $PRIV_IFACE -d $PRIVATE_IP -p ALL -j
ACCEPT
fi

 

[Joe Regular]

In the output of kiss when it starts I noticed there appears to be an
error.

"/usr/sbin/kiss: line 341: [: eth0: unary operator expected"

Line 341:

if [ ! "$PRIV_IFACE" == ""]; then
$IPTABLES -A INPUT -s 0/0 -e $PRIV_IFACE -d $PRIVATE_IP -p ALL -j
ACCEPT
fi

I will have to brush up on my shell scripting sytax to see what is wrong
with comparison but hopefully that does the trick!

Thanks

I beleive this rule should enable me to reach the DNS servers from eth0
since PRIV_IFACE is set to eth0. Do you see anything wrong with it?

##############################################################################
#
# To define your private network, use the PRIV_IFACE configuration
# variable above.
#
# We allow all traffic in and out of the private network
if [ ! "$PRIV_IFACE" == ""]; then
$IPTABLES -A INPUT -s 0/0 -e $PRIV_IFACE -d $PRIVATE_IP -p ALL -j
ACCEPT
fi

I think I remember seeing a rule that inhibited outbound connections of
any
kind except from the public interface (eth1). If your DNS servers are on
a
different network, then you won't be able to reach them. If dig just
hangs,
then you know it's a connectivity problem. Do you have any DNS servers
you
can access (like from your ISP) from your public interface?