Add interface name to address translation to pfctl, document it and add

a regress test. Translation is done on rule set load-time only, so the
rule sets must be reloaded when an interface address changes.
parse.y patch from Cedric Berger. Similar patch from Jonathon Fletcher.
Thanks to both.

2 files changed, 29 insertions, 6 deletions

diff --git a/share/man/man5/nat.conf.5 b/share/man/man5/nat.conf.5
index e9c7fbb7ba6..bee513c1519 100644
--- a/share/man/man5/nat.conf.5
+++ b/share/man/man5/nat.conf.5
@@ -1,4 +1,4 @@
-.\"	$OpenBSD: nat.conf.5,v 1.15 2001/10/05 14:45:54 mpech Exp $
+.\"	$OpenBSD: nat.conf.5,v 1.16 2001/10/07 11:56:57 dhartmei Exp $
 .\"
 .\" Copyright (c) 2001 Ian Darwin.  All rights reserved.
 .\"
@@ -88,9 +88,19 @@ Comments begin with the character `#'; empty lines are ignored.
 An
 .Em ifname
 is a network interface such as fxp4, ne0, or ep1.
-An
 .Em address
-is an IP address.
+can be specified in CIDR notation (matching netblocks), as
+symbolic host names or interface names.
+Host name resolution and interface to address translation are done at rule
+set load-time.
+When the address of an interface (or host name) changes (by DHCP or PPP,
+for instance), the rule set must be reloaded for the change to be reflected
+in the kernel.
+See
+.Xr dhclient-script 8
+or
+.Xr ppp 8
+for information on how to automate this task.
 If specified,
 .Em mask-bits
 refers to the number of bits in the netmask.
diff --git a/share/man/man5/pf.conf.5 b/share/man/man5/pf.conf.5
index 497e49179fa..3c93aadc269 100644
--- a/share/man/man5/pf.conf.5
+++ b/share/man/man5/pf.conf.5
@@ -1,4 +1,4 @@
-.\"	$OpenBSD: pf.conf.5,v 1.20 2001/10/05 14:45:54 mpech Exp $
+.\"	$OpenBSD: pf.conf.5,v 1.21 2001/10/07 11:56:57 dhartmei Exp $
 .\"
 .\" Copyright (c) 2001, Daniel Hartmeier
 .\" All rights reserved.
@@ -186,8 +186,21 @@ Common protocols used here are tcp, udp, icmp and ipv6-icmp.
 .Ss from <source> port <source> to <dest> port <dest>
 The rule applies only to packets with the specified source and destination
 addresses/ports.
-Addresses can be specified in CIDR notation (matching netblocks) and ports
-can be specified using these operators
+.Pp
+Addresses can be specified in CIDR notation (matching netblocks), as
+symbolic host names or interface names.
+Host name resolution and interface to address translation are done at
+rule set load-time.
+When the address of an interface (or host name) changes (by DHCP or PPP,
+for instance), the rule set must be reloaded for the change to be reflected
+in the kernel.
+See
+.Xr dhclient-script 8
+or
+.Xr ppp 8
+for information on how to automate this task.
+.Pp
+Ports can be specified using these operators
 .Bd -literal
     = (equal), != (unequal), < (lesser), <= (lesser or equal), > (greater),
     >= (greater or equal), >< (range) and <> (except range).