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diff --git a/doc/policygroups.html b/doc/policygroups.html deleted file mode 100644 index 6a507b1f6..000000000 --- a/doc/policygroups.html +++ /dev/null @@ -1,341 +0,0 @@ -<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN" "http://www.w3.org/TR/REC-html40/loose.dtd"> -<HTML> -<HEAD> -<TITLE>Introduction to FreeS/WAN</TITLE> -<META HTTP-EQUIV="Content-Type" CONTENT="text/html; CHARSET=iso-8859-1"> -<STYLE TYPE="text/css"><!-- -BODY { font-family: serif } -H1 { font-family: sans-serif } -H2 { font-family: sans-serif } -H3 { font-family: sans-serif } -H4 { font-family: sans-serif } -H5 { font-family: sans-serif } -H6 { font-family: sans-serif } -SUB { font-size: smaller } -SUP { font-size: smaller } -PRE { font-family: monospace } ---></STYLE> -</HEAD> -<BODY> -<A HREF="toc.html">Contents</A> -<A HREF="quickstart.html">Previous</A> -<A HREF="faq.html">Next</A> -<HR> -<H1><A NAME="4">How to Configure Linux FreeS/WAN with Policy Groups</A></H1> -<A NAME="policygroups"></A> -<H2><A NAME="4_1">What are Policy Groups?</A></H2> -<P><STRONG>Policy Groups</STRONG> are an elegant general mechanism to - configure FreeS/WAN. They are useful for many FreeS/WAN users.</P> -<P>In previous FreeS/WAN versions, you needed to configure each IPsec - connection explicitly, on both local and remote hosts. This could - become complex.</P> -<P>By contrast, Policy Groups allow you to set local IPsec policy for - lists of remote hosts and networks, simply by listing the hosts and - networks which you wish to have special treatment in one of several - Policy Group files. FreeS/WAN then internally creates the connections - needed to implement each policy.</P> -<P>In the next section we describe our five Base Policy Groups, which - you can use to configure IPsec in many useful ways. Later, we will show - you how to create an IPsec VPN using one line of configuration for each - remote host or network.</P> -<A NAME="builtin_policygroups"></A> -<H3><A NAME="4_1_1">Built-In Security Options</A></H3> -<P>FreeS/WAN offers these Base Policy Groups:</P> -<DL> -<DT>private</DT> -<DD> FreeS/WAN only communicates privately with the listed<A HREF="glossary.html#CIDR"> - CIDR</A> blocks. If needed, FreeS/WAN attempts to create a connection - opportunistically. If this fails, FreeS/WAN blocks communication. - Inbound blocking is assumed to be done by the firewall. FreeS/WAN - offers firewall hooks but no modern firewall rules to help with inbound - blocking.</DD> -<DT>private-or-clear</DT> -<DD> FreeS/WAN prefers private communication with the listed CIDR - blocks. If needed, FreeS/WAN attempts to create a connection - opportunistically. If this fails, FreeS/WAN allows traffic in the - clear.</DD> -<DT>clear-or-private</DT> -<DD> FreeS/WAN communicates cleartext with the listed CIDR blocks, but - also accepts inbound OE connection requests from them. Also known as<A HREF="glossary.html#passive.OE"> - passive OE (pOE)</A>, this policy may be used to create an<A HREF="glossary.html#responder"> - opportunistic responder</A>.</DD> -<DT>clear</DT> -<DD> FreeS/WAN only communicates cleartext with the listed CIDR blocks.</DD> -<DT>block</DT> -<DD>FreeS/WAN blocks traffic to and from and the listed CIDR blocks. - Inbound blocking is assumed to be done by the firewall. FreeS/WAN - offers firewall hooks but no modern firewall rules to help with inbound - blocking. -<!-- also called "blockdrop".--> -</DD> -</DL> -<A NAME="policy.group.notes"></A> -<P>Notes:</P> -<UL> -<LI>Base Policy Groups apply to communication with this host only.</LI> -<LI>The most specific rule (whether policy or pre-configured connection) - applies. This has several practical applications: -<UL> -<LI>If CIDR blocks overlap, FreeS/WAN chooses the most specific - applicable block.</LI> -<LI>This decision also takes into account any pre-configured connections - you may have.</LI> -<LI>If the most specific connection is a pre-configured connection, the - following procedure applies. If that connection is up, it will be used. - If it is routed, it will be brought up. If it is added, no action will - be taken.</LI> -</UL> -</LI> -<LI>Base Policy Groups are created using built-in connections. Details - in<A HREF="manpage.d/ipsec.conf.5.html"> man ipsec.conf</A>.</LI> -<LI>All Policy Groups are bidirectional.<A HREF="src/policy-groups-table.html"> - This chart</A> shows some technical details. FreeS/WAN does not support - one-way encryption, since it can give users a false sense of security.</LI> -</UL> -<H2><A NAME="4_2">Using Policy Groups</A></H2> -<P>The Base Policy Groups which build IPsec connections rely on - Opportunistic Encryption. To use the following examples, you must first - become OE-capable, as described in our<A HREF="quickstart.html#quickstart"> - quickstart guide</A>.<A NAME="example1"></A></P> -<H3><A NAME="4_2_1">Example 1: Using a Base Policy Group</A></H3> -<P>Simply place CIDR blocks (<A HREF="#dnswarning">names</A>, IPs or IP - ranges) in /etc/ipsec.d/policies/<VAR>[groupname]</VAR>, and reread the - policy group files.</P> -<P>For example, the<VAR> private-or-clear</VAR> policy tells FreeS/WAN - to prefer encrypted communication to the listed CIDR blocks. Failing - that, it allows talk in the clear.</P> -<P>To make this your default policy, place<A HREF="glossary.html#fullnet"> - fullnet</A> in the<VAR> private-or-clear</VAR> policy group file:</P> -<PRE> [root@xy root]# cat /etc/ipsec.d/policies/private-or-clear - # This file defines the set of CIDRs (network/mask-length) to which - # communication should be private, if possible, but in the clear otherwise. - .... - 0.0.0.0/0</PRE> -<P>and reload your policies with</P> -<PRE> ipsec auto --rereadgroups</PRE> -<P>Use<A HREF="quickstart.html#opp.test"> this test</A> to verify - opportunistic connections.</P> -<A NAME="example2"></A> -<H3><A NAME="4_2_2">Example 2: Defining IPsec Security Policy with - Groups</A></H3> -<P>Defining IPsec security policy with Base Policy Groups is like - creating a shopping list: just put CIDR blocks in the appropriate group - files. For example:</P> -<PRE> [root@xy root]# cd /etc/ipsec.d/policies - [root@xy policies]# cat private - 192.0.2.96/27 # The finance department - 192.0.2.192/29 # HR - 192.0.2.12 # HR gateway - irc.private.example.com # Private IRC server - - [root@xy policies]# cat private-or-clear - 0.0.0.0/0 # My default policy: try to encrypt. - - [root@xy policies]# cat clear - 192.0.2.18/32 # My POP3 server - 192.0.2.19/32 # My Web proxy - - [root@xy policies]# cat block - spamsource.example.com</PRE> -<P>To make these settings take effect, type:</P> -<PRE> ipsec auto --rereadgroups</PRE> -<P>Notes:</P> -<UL> -<LI>For opportunistic connection attempts to succeed, all participating - FreeS/WAN hosts and gateways must be configured for OE.</LI> -<LI>Examples 3 through 5 show how to implement a detailed<VAR> private</VAR> - policy.</LI> -<LI><A NAME="dnswarning"></A><FONT COLOR="RED"> Warning:</FONT> Using - DNS names in policy files and ipsec.conf can be tricky. If the name - does not resolve, the policy will not be implemented for that name. It - is therefore safer either to use IPs, or to put any critical names in - /etc/hosts. We plan to implement periodic DNS retry to help with this. -<BR> Names are resolved at FreeS/WAN startup, or when the policies are - reloaded. Unfortunately, name lookup can hold up the startup process. - If you have fast DNS servers, the problem may be less severe.</LI> -</UL> -<A HREF="example3"></A> -<H3><A NAME="4_2_3">Example 3: Creating a Simple IPsec VPN with the<VAR> - private</VAR> Group</A></H3> -<P>You can create an IPsec VPN between several hosts, with only one line - of configuration per host, using the<VAR> private</VAR> policy group.</P> -<P>First, use our<A HREF="quickstart.html"> quickstart guide</A> to set - up each participating host with a FreeS/WAN install and OE.</P> -<P>In one host's<VAR> /etc/ipsec.d/policies/private</VAR>, list the - peers to which you wish to protect traffic. For example:</P> -<PRE> [root@xy root]# cd /etc/ipsec.d/policies - [root@xy policies]# cat private - 192.0.2.9 # several hosts at example.com - 192.0.2.11 - 192.0.2.12 - irc.private.example.com -</PRE> -<P>Copy the<VAR> private</VAR> file to each host. Remove the local host, - and add the initial host.</P> -<PRE> scp2 /etc/ipsec.d/policies/private root@192.0.2.12:/etc/ipsec.d/policies/private</PRE> -<P>On each host, reread the policy groups with</P> -<PRE> ipsec auto --rereadgroups</PRE> -<P>That's it! You're configured.</P> -<P>Test by pinging between two hosts. After a second or two, traffic - should flow, and</P> -<PRE> ipsec eroute</PRE> -<P>should yield something like</P> -<PRE> 192.0.2.11/32 -> 192.0.2.8/32 => tun0x149f@192.0.2.8</PRE> -<P>where your host IPs are substituted for 192.0.2.11 and 192.0.2.8.</P> -<P>If traffic does not flow, there may be an error in your OE setup. - Revisit our<A HREF="quickstart.html"> quickstart guide</A>.</P> -<P>Our next two examples show you how to add subnets to this IPsec VPN.</P> -<A NAME="example4"></A> -<H3><A NAME="4_2_4">Example 4: New Policy Groups to Protect a Subnet</A></H3> -<P>To protect traffic to a subnet behind your FreeS/WAN gateway, you'll - need additional DNS records, and new policy groups. To set up the DNS, - see our<A HREF="quickstart.html#opp.gate"> quickstart guide</A>. To - create five new policy groups for your subnet, copy these connections - to<VAR> /etc/ipsec.conf</VAR>. Substitute your subnet's IPs for - 192.0.2.128/29.</P> -<PRE> -conn private-net - also=private # inherits settings (eg. auto=start) from built in conn - leftsubnet=192.0.2.128/29 # your subnet's IPs here - -conn private-or-clear-net - also=private-or-clear - leftsubnet=192.0.2.128/29 - -conn clear-or-private-net - also=clear-or-private - leftsubnet=192.0.2.128/29 - -conn clear-net - also=clear - leftsubnet=192.0.2.128/29 - -conn block-net - also=block - leftsubnet=192.0.2.128/29 -</PRE> -<P>Copy the gateway's files to serve as the initial policy group files - for the new groups:</P> -<PRE> - cp -p /etc/ipsec.d/policies/private /etc/ipsec.d/policies/private-net - cp -p /etc/ipsec.d/policies/private-or-clear /etc/ipsec.d/policies/private-or-clear-net - cp -p /etc/ipsec.d/policies/clear-or-private /etc/ipsec.d/policies/clear-or-private-net - cp -p /etc/ipsec.d/policies/clear /etc/ipsec.d/policies/clear-net - cp -p /etc/ipsec.d/policies/block /etc/ipsec.d/policies/block -</PRE> -<P><STRONG>Tip: Since a missing policy group file is equivalent to a - file with no entries, you need only create files for the connections - you'll use.</STRONG></P> -<P>To test one of your new groups, place the fullnet 0.0.0.0/0 in<VAR> - private-or-clear-net</VAR>. Perform the subnet test in<A HREF="quickstart.html#opp.test"> - our quickstart guide</A>. You should see a connection, and</P> -<PRE> ipsec eroute</PRE> -<P>should include an entry which mentions the subnet node's IP and the - OE test site IP, like this:</P> -<PRE> 192.0.2.131/32 -> 192.139.46.77/32 => tun0x149f@192.0.2.11</PRE> -<A HREF="example5"></A> -<H3><A NAME="4_2_5">Example 5: Adding a Subnet to the VPN</A></H3> -<P>Suppose you wish to secure traffic to a subnet 192.0.2.192/29 behind - a FreeS/WAN box 192.0.2.12.</P> -<P>First, add DNS entries to configure 192.0.2.12 as an opportunistic - gateway for that subnet. Instructions are in our<A HREF="quickstart.html#opp.gate"> - quickstart guide</A>. Next, create a<VAR> private-net</VAR> group on - 192.0.2.12 as described in<A HREF="#example4"> Example 4</A>.</P> -<P>On each other host, add the subnet 192.0.2.192/29 to<VAR> private</VAR> -, yielding for example</P> -<PRE> [root@xy root]# cd /etc/ipsec.d/policies - [root@xy policies]# cat private - 192.0.2.9 # several hosts at example.com - 192.0.2.11 - 192.0.2.12 # HR department gateway - 192.0.2.192/29 # HR subnet - irc.private.example.com -</PRE> -<P>and reread policy groups with</P> -<PRE> ipsec auto --rereadgroups</PRE> -<P>That's all the configuration you need.</P> -<P>Test your VPN by pinging from a machine on 192.0.2.192/29 to any - other host:</P> -<PRE> [root@192.0.2.194]# ping 192.0.2.11</PRE> -<P>After a second or two, traffic should flow, and</P> -<PRE> ipsec eroute</PRE> -<P>should yield something like</P> -<PRE> 192.0.2.11/32 -> 192.0.2.194/32 => tun0x149f@192.0.2.12 -</PRE> -<P>Key:</P> -<TABLE> -<TR><TD>1.</TD><TD>192.0.2.11/32</TD><TD>Local start point of the - protected traffic.</TD></TR> -<TR><TD>2.</TD><TD>192.0.2.194/32</TD><TD>Remote end point of the - protected traffic.</TD></TR> -<TR><TD>3.</TD><TD>192.0.2.12</TD><TD>Remote FreeS/WAN node (gateway or - host). May be the same as (2).</TD></TR> -<TR><TD>4.</TD><TD>[not shown]</TD><TD>Local FreeS/WAN node (gateway or - host), where you've produced the output. May be the same as (1).</TD></TR> -</TABLE> -<P>For additional assurance, you can verify with a packet sniffer that - the traffic is being encrypted.</P> -<P>Note</P> -<UL> -<LI>Because strangers may also connect via OE, this type of VPN may - require a stricter firewalling policy than a conventional VPN.</LI> -</UL> -<H2><A NAME="4_3">Appendix</A></H2> -<A NAME="hiddenconn"></A> -<H3><A NAME="4_3_1">Our Hidden Connections</A></H3> -<P>Our Base Policy Groups are created using hidden connections. These - are spelled out in<A HREF="manpage.d/ipsec.conf.5.html"> man ipsec.conf</A> - and defined in<VAR> /usr/local/lib/ipsec/_confread</VAR>.</P> -<A NAME="custom_policygroups"></A> -<H3><A NAME="4_3_2">Custom Policy Groups</A></H3> -<P>A policy group is built using a special connection description in<VAR> - ipsec.conf</VAR>, which:</P> -<UL> -<LI>is<STRONG> generic</STRONG>. It uses<VAR> - right=[%group|%opportunisticgroup]</VAR> rather than specific IPs. The - connection is cloned for every name or IP range listed in its Policy - Group file.</LI> -<LI>often has a<STRONG> failure rule</STRONG>. This rule, written<VAR> - failureshunt=[passthrough|drop|reject|none]</VAR>, tells FreeS/WAN what - to do with packets for these CIDRs if it fails to establish the - connection. Default is<VAR> none</VAR>.</LI> -</UL> -<P>To create a new group:</P> -<OL> -<LI>Create its connection definition in<VAR> ipsec.conf</VAR>.</LI> -<LI>Create a Policy Group file in<VAR> /etc/ipsec.d/policies</VAR> with - the same name as your connection.</LI> -<LI>Put a CIDR block in that file.</LI> -<LI>Reread groups with<VAR> ipsec auto --rereadgroups</VAR>.</LI> -<LI>Test:<VAR> ping</VAR> to activate any OE connection, and view - results with<VAR> ipsec eroute</VAR>.</LI> -</OL> -<A NAME="disable_oe"></A><A NAME="disable_policygroups"></A> -<H3><A NAME="4_3_3">Disabling Opportunistic Encryption</A></H3> -<P>To disable OE (eg. policy groups and packetdefault), cut and paste - the following lines to<VAR> /etc/ipsec.conf</VAR>:</P> -<PRE>conn block - auto=ignore - -conn private - auto=ignore - -conn private-or-clear - auto=ignore - -conn clear-or-private - auto=ignore - -conn clear - auto=ignore - -conn packetdefault - auto=ignore</PRE> -<P>Restart FreeS/WAN so that the changes take effect:</P> -<PRE> ipsec setup restart</PRE> -<HR> -<A HREF="toc.html">Contents</A> -<A HREF="quickstart.html">Previous</A> -<A HREF="faq.html">Next</A> -</BODY> -</HTML> |