IPv6 qmail
==========

Copyright (c) 2005. 

   Eric Pancer <eric@catastrophe.net>. All Rights Reserved.

Original Release: 2005-04-30

Revision 1.1 - 2005-05-10 : Updated to use fefe's diff15 for ucspi-tcp.
                            Thanks to bh at izb.knu.ac.kr.

Other portions of this document are copyright their specific owners. Please
check with those copyright holders before reusing thier work. This document
is compiled in order to easily distribute the patches for qmail.

-------
summary
-------

Are you looking to enable qmail on your IPv6 enabled hosts? I was too, and
found it to be a bit of a problem. However, if you follow this document
you should get support in a matter of minutes. 

This document was compiled using OpenBSD 3.4 and OpenBSD 3.6 test platforms.
Other UNIX variants may differ, so please test and send any comments or

---------
ucspi-tcp
---------

ucspi-tcp is a generic TCP client/server application written by Dan
Berstein. More information on ucspi-tcp can be found at:

  <http://cr.yp.to/ucspi-tcp.html>

qmail uses ucspi-tcp to listen for incoming connections on the network.
Therefore it must be IPv6 enabled if you wish to accept mail.

1. Get ucspi-tcp-0.88.tar.gz from <ftp://cr.yp.to>.
2. Untar ucspi-tcp.
3. There is Fefe's patch for IPv6 support below [1]. However,
   this patch needs to be patched with [2] for OpenBSD 3.4 and higher.
4. Then, patch the ucspi-tcp sources with fefe's patch.
5. Run `make setup check.'
6. Now you're done; take note of the new "-4" and "-6" flags in
   tcpclient(1) and tcpserver(1).

--------
netqmail
--------

netqmail are the recommended patches compiled by various qmail authorities.
More information on netqmail can be found at <http://www.netqmail.org/>.

The following patches netqmail except for one file, ipme.c. As I am not a C
guru, the best I found to do was replace the original file from qmail-1.03.
If you have a better solution, please let me know.

1. Download netqmail-1.05
2. Untar netqmail and run `collate.sh'
3. Copy ipme.c from the original qmail-1.03 distribution
   into the netqmail-1.05 source directory.
4. Patch the netqmail-1.05 sources with the IPv6 patch
   found below [3].
5. Run `make setup check` after stopping your qmail daemons (if running).
6. Start the daemons, however you do so, and test.

-------
patches
-------

[1] Fefe's IPv6 support patch for ucspi-tcp. 
    Original location is <http://www.fefe.de/ucspi/>

### start ucspi-tcp-0.88-ipv6.diff15
diff -uNr ucspi-tcp-0.88/FILES ucspi-tcp-0.88-ipv6/FILES
--- ucspi-tcp-0.88/FILES	2000-03-18 16:18:42.000000000 +0100
+++ ucspi-tcp-0.88-ipv6/FILES	2005-04-23 12:54:56.878046928 +0200
@@ -216,3 +216,40 @@
 warn-auto.sh
 warn-shsgr
 x86cpuid.c
+dns_ip6.c
+dns_ipq6.c
+dns_nd6.c
+dns_sortip6.c
+fmt_xlong.c
+ip6_fmt.c
+ip6_scan.c
+scan_0x.c
+socket_accept6.c
+socket_bind6.c
+socket_conn6.c
+socket_local6.c
+socket_recv6.c
+socket_remote6.c
+socket_send6.c
+socket_tcp6.c
+timeoutconn6.c
+tryip6.c
+haveip6.h2
+haveip6.h1
+remoteinfo6.c
+addcr.1
+argv0.1
+date@.1
+delcr.1
+finger@.1
+fixcr.1
+http@.1
+mconnect.1
+recordio.1
+tcp-environ.5
+tcpcat.1
+tcpclient.1
+tcprules.1
+tcprulescheck.1
+tcpserver.1
+who@.1
diff -uNr ucspi-tcp-0.88/Makefile ucspi-tcp-0.88-ipv6/Makefile
--- ucspi-tcp-0.88/Makefile	2000-03-18 16:18:42.000000000 +0100
+++ ucspi-tcp-0.88-ipv6/Makefile	2005-04-23 12:54:56.880046624 +0200
@@ -76,12 +76,14 @@
 makelib byte_chr.o byte_copy.o byte_cr.o byte_diff.o byte_rchr.o \
 byte_zero.o case_diffb.o case_diffs.o fmt_ulong.o ip4_fmt.o \
 ip4_scan.o scan_ulong.o str_chr.o str_diff.o str_len.o str_start.o \
-uint16_pack.o uint16_unpack.o uint32_pack.o uint32_unpack.o
+uint16_pack.o uint16_unpack.o uint32_pack.o uint32_unpack.o \
+ip6_fmt.o scan_ip6.o scan_xlong.o fmt_xlong.o
 	./makelib byte.a byte_chr.o byte_copy.o byte_cr.o \
 	byte_diff.o byte_rchr.o byte_zero.o case_diffb.o \
 	case_diffs.o fmt_ulong.o ip4_fmt.o ip4_scan.o scan_ulong.o \
 	str_chr.o str_diff.o str_len.o str_start.o uint16_pack.o \
-	uint16_unpack.o uint32_pack.o uint32_unpack.o
+	uint16_unpack.o uint32_pack.o uint32_unpack.o ip6_fmt.o \
+	scan_ip6.o scan_xlong.o fmt_xlong.o
 
 byte_chr.o: \
 compile byte_chr.c byte.h
@@ -181,11 +183,13 @@
 dns.a: \
 makelib dns_dfd.o dns_domain.o dns_dtda.o dns_ip.o dns_ipq.o \
 dns_name.o dns_nd.o dns_packet.o dns_random.o dns_rcip.o dns_rcrw.o \
-dns_resolve.o dns_sortip.o dns_transmit.o dns_txt.o
+dns_resolve.o dns_sortip.o dns_transmit.o dns_txt.o dns_ip6.o \
+dns_sortip6.o dns_nd6.o dns_ipq6.o
 	./makelib dns.a dns_dfd.o dns_domain.o dns_dtda.o dns_ip.o \
 	dns_ipq.o dns_name.o dns_nd.o dns_packet.o dns_random.o \
 	dns_rcip.o dns_rcrw.o dns_resolve.o dns_sortip.o \
-	dns_transmit.o dns_txt.o
+	dns_transmit.o dns_txt.o dns_ip6.o dns_sortip6.o dns_nd6.o \
+	dns_ipq6.o
 
 dns_dfd.o: \
 compile dns_dfd.c error.h alloc.h byte.h dns.h stralloc.h gen_alloc.h \
@@ -257,7 +261,7 @@
 dns_transmit.o: \
 compile dns_transmit.c socket.h uint16.h alloc.h error.h byte.h \
 readwrite.h uint16.h dns.h stralloc.h gen_alloc.h iopause.h taia.h \
-tai.h uint64.h taia.h
+tai.h uint64.h taia.h uint32.h
 	./compile dns_transmit.c
 
 dns_txt.o: \
@@ -498,9 +502,15 @@
 remoteinfo.o: \
 compile remoteinfo.c fmt.h buffer.h socket.h uint16.h error.h \
 iopause.h taia.h tai.h uint64.h timeoutconn.h uint16.h remoteinfo.h \
-stralloc.h gen_alloc.h uint16.h
+stralloc.h gen_alloc.h uint16.h uint32.h
 	./compile remoteinfo.c
 
+remoteinfo6.o: \
+compile remoteinfo6.c fmt.h buffer.h socket.h uint16.h error.h \
+iopause.h taia.h tai.h uint64.h timeoutconn.h uint16.h remoteinfo.h \
+stralloc.h gen_alloc.h uint16.h uint32.h
+	./compile remoteinfo6.c
+
 rts: \
 warn-auto.sh rts.sh conf-home
 	cat warn-auto.sh rts.sh \
@@ -557,43 +567,43 @@
 	rm -f trylsock.o trylsock
 
 socket_accept.o: \
-compile socket_accept.c byte.h socket.h uint16.h
+compile socket_accept.c byte.h socket.h uint16.h uint32.h
 	./compile socket_accept.c
 
 socket_bind.o: \
-compile socket_bind.c byte.h socket.h uint16.h
+compile socket_bind.c byte.h socket.h uint16.h uint32.h
 	./compile socket_bind.c
 
 socket_conn.o: \
-compile socket_conn.c readwrite.h byte.h socket.h uint16.h
+compile socket_conn.c readwrite.h byte.h socket.h uint16.h uint32.h
 	./compile socket_conn.c
 
 socket_delay.o: \
-compile socket_delay.c socket.h uint16.h
+compile socket_delay.c socket.h uint16.h uint32.h
 	./compile socket_delay.c
 
 socket_listen.o: \
-compile socket_listen.c socket.h uint16.h
+compile socket_listen.c socket.h uint16.h uint32.h
 	./compile socket_listen.c
 
 socket_local.o: \
-compile socket_local.c byte.h socket.h uint16.h
+compile socket_local.c byte.h socket.h uint16.h uint32.h
 	./compile socket_local.c
 
 socket_opts.o: \
-compile socket_opts.c socket.h uint16.h
+compile socket_opts.c socket.h uint16.h uint32.h
 	./compile socket_opts.c
 
 socket_remote.o: \
-compile socket_remote.c byte.h socket.h uint16.h
+compile socket_remote.c byte.h socket.h uint16.h uint32.h
 	./compile socket_remote.c
 
 socket_tcp.o: \
-compile socket_tcp.c ndelay.h socket.h uint16.h
+compile socket_tcp.c ndelay.h socket.h uint16.h uint32.h
 	./compile socket_tcp.c
 
 socket_udp.o: \
-compile socket_udp.c ndelay.h socket.h uint16.h
+compile socket_udp.c ndelay.h socket.h uint16.h uint32.h
 	./compile socket_udp.c
 
 str_chr.o: \
@@ -710,9 +720,9 @@
 	chmod 755 tcpcat
 
 tcpclient: \
-load tcpclient.o remoteinfo.o timeoutconn.o dns.a time.a unix.a \
-byte.a socket.lib
-	./load tcpclient remoteinfo.o timeoutconn.o dns.a time.a \
+load tcpclient.o remoteinfo6.o dns.a time.a unix.a \
+byte.a socket.lib byte.h timeoutconn6.o
+	./load tcpclient remoteinfo6.o timeoutconn6.o dns.a time.a \
 	unix.a byte.a  `cat socket.lib`
 
 tcpclient.o: \
@@ -720,7 +730,7 @@
 scan.h str.h ip4.h uint16.h socket.h uint16.h fd.h stralloc.h \
 gen_alloc.h buffer.h error.h strerr.h pathexec.h timeoutconn.h \
 uint16.h remoteinfo.h stralloc.h uint16.h dns.h stralloc.h iopause.h \
-taia.h tai.h uint64.h taia.h
+taia.h tai.h uint64.h taia.h uint32.h
 	./compile tcpclient.c
 
 tcprules: \
@@ -742,9 +752,9 @@
 	./compile tcprulescheck.c
 
 tcpserver: \
-load tcpserver.o rules.o remoteinfo.o timeoutconn.o cdb.a dns.a \
+load tcpserver.o rules.o remoteinfo6.o timeoutconn6.o cdb.a dns.a \
 time.a unix.a byte.a socket.lib
-	./load tcpserver rules.o remoteinfo.o timeoutconn.o cdb.a \
+	./load tcpserver rules.o remoteinfo6.o timeoutconn6.o cdb.a \
 	dns.a time.a unix.a byte.a  `cat socket.lib`
 
 tcpserver.o: \
@@ -753,7 +763,7 @@
 alloc.h buffer.h error.h strerr.h sgetopt.h subgetopt.h pathexec.h \
 socket.h uint16.h ndelay.h remoteinfo.h stralloc.h uint16.h rules.h \
 stralloc.h sig.h dns.h stralloc.h iopause.h taia.h tai.h uint64.h \
-taia.h
+taia.h uint32.h
 	./compile tcpserver.c
 
 time.a: \
@@ -765,9 +775,14 @@
 
 timeoutconn.o: \
 compile timeoutconn.c ndelay.h socket.h uint16.h iopause.h taia.h \
-tai.h uint64.h error.h timeoutconn.h uint16.h
+tai.h uint64.h error.h timeoutconn.h uint16.h uint32.h
 	./compile timeoutconn.c
 
+timeoutconn6.o: \
+compile timeoutconn6.c ndelay.h socket.h uint16.h iopause.h taia.h \
+tai.h uint64.h error.h timeoutconn.h uint16.h uint32.h
+	./compile timeoutconn6.c
+
 uint16_pack.o: \
 compile uint16_pack.c uint16.h
 	./compile uint16_pack.c
@@ -806,7 +821,12 @@
 socket_opts.o socket_remote.o socket_tcp.o socket_udp.o \
 stralloc_cat.o stralloc_catb.o stralloc_cats.o stralloc_copy.o \
 stralloc_eady.o stralloc_opyb.o stralloc_opys.o stralloc_pend.o \
-strerr_die.o strerr_sys.o subgetopt.o wait_nohang.o wait_pid.o
+strerr_die.o strerr_sys.o subgetopt.o wait_nohang.o wait_pid.o \
+socket_conn6.o socket_bind6.o socket_accept6.o socket_recv6.o \
+socket_send6.o socket_local6.o socket_remote6.o socket_tcp6.o \
+socket_getifname.o socket_getifidx.o socket_v4mappedprefix.o \
+socket_ip4loopback.o socket_v6any.o socket_v6loopback.o \
+socket_udp6.o
 	./makelib unix.a alloc.o alloc_re.o buffer.o buffer_0.o \
 	buffer_1.o buffer_2.o buffer_copy.o buffer_get.o \
 	buffer_put.o env.o error.o error_str.o fd_copy.o fd_move.o \
@@ -819,7 +839,12 @@
 	socket_udp.o stralloc_cat.o stralloc_catb.o stralloc_cats.o \
 	stralloc_copy.o stralloc_eady.o stralloc_opyb.o \
 	stralloc_opys.o stralloc_pend.o strerr_die.o strerr_sys.o \
-	subgetopt.o wait_nohang.o wait_pid.o
+	subgetopt.o wait_nohang.o wait_pid.o socket_conn6.o \
+	socket_bind6.o socket_accept6.o socket_recv6.o socket_send6.o \
+	socket_local6.o socket_remote6.o socket_tcp6.o \
+	socket_getifname.o socket_getifidx.o socket_v4mappedprefix.o \
+	socket_ip4loopback.o socket_v6any.o socket_v6loopback.o \
+	socket_udp6.o
 
 wait_nohang.o: \
 compile wait_nohang.c haswaitp.h
@@ -835,3 +860,110 @@
 	| sed s}HOME}"`head -1 conf-home`"}g \
 	> who@
 	chmod 755 who@
+
+socket_conn6.o: \
+compile socket_conn6.c socket.h uint16.h haveip6.h error.h ip6.h \
+uint32.h
+	./compile socket_conn6.c
+
+socket_bind6.o: \
+compile socket_bind6.c socket.h uint16.h haveip6.h error.h ip6.h \
+uint32.h
+	./compile socket_bind6.c
+
+socket_accept6.o: \
+compile socket_accept6.c socket.h uint16.h haveip6.h error.h ip6.h \
+uint32.h
+	./compile socket_accept6.c
+
+socket_recv6.o: \
+compile socket_recv6.c socket.h uint16.h haveip6.h error.h ip6.h \
+uint32.h
+	./compile socket_recv6.c
+
+socket_send6.o: \
+compile socket_send6.c socket.h uint16.h haveip6.h error.h uint32.h
+	./compile socket_send6.c
+
+socket_local6.o: \
+compile socket_local6.c socket.h uint16.h haveip6.h error.h uint32.h
+	./compile socket_local6.c
+
+socket_remote6.o: \
+compile socket_remote6.c socket.h uint16.h haveip6.h error.h uint32.h
+	./compile socket_remote6.c
+
+dns_sortip6.o: \
+compile dns_sortip6.c byte.h dns.h stralloc.h gen_alloc.h iopause.h \
+taia.h tai.h uint64.h taia.h
+	./compile dns_sortip6.c
+
+dns_nd6.o: \
+compile dns_nd6.c byte.h fmt.h dns.h stralloc.h gen_alloc.h iopause.h \
+taia.h tai.h uint64.h taia.h
+	./compile dns_nd6.c
+
+dns_ipq6.o: \
+compile dns_ipq6.c stralloc.h gen_alloc.h case.h byte.h str.h dns.h \
+stralloc.h iopause.h taia.h tai.h uint64.h taia.h ip6.h
+	./compile dns_ipq6.c
+
+dns_ip6.o: \
+compile dns_ip6.c stralloc.h gen_alloc.h uint16.h byte.h dns.h \
+stralloc.h iopause.h taia.h tai.h uint64.h taia.h
+	./compile dns_ip6.c
+
+fmt_xlong.o: \
+compile fmt_xlong.c scan.h
+	./compile fmt_xlong.c
+
+scan_xlong.o: \
+compile scan_xlong.c scan.h
+	./compile scan_xlong.c
+
+ip6_fmt.o: \
+compile ip6_fmt.c fmt.h ip6.h
+	./compile ip6_fmt.c
+
+scan_ip6.o: \
+compile scan_ip6.c scan.h ip6.h
+	./compile scan_ip6.c
+
+socket_tcp6.o: \
+compile socket_tcp6.c ndelay.h socket.h uint16.h uint32.h
+	./compile socket_tcp6.c
+
+socket_udp6.o: \
+compile socket_udp6.c ndelay.h socket.h uint16.h uint32.h
+	./compile socket_udp6.c
+
+haveip6.h: \
+tryip6.c choose compile haveip6.h1 haveip6.h2
+	./choose c tryip6 haveip6.h1 haveip6.h2 > haveip6.h
+
+socket_getifname.o: \
+compile socket_getifname.c socket.h uint16.h uint32.h
+	./compile socket_getifname.c
+
+socket_getifidx.o: \
+compile socket_getifidx.c socket.h uint16.h uint32.h
+	./compile socket_getifidx.c
+
+socket_ip4loopback.o: \
+compile socket_ip4loopback.c
+	./compile socket_ip4loopback.c
+
+socket_v4mappedprefix.o: \
+compile socket_v4mappedprefix.c
+	./compile socket_v4mappedprefix.c
+
+socket_v6any.o: \
+compile socket_v6any.c
+	./compile socket_v6any.c
+
+socket_v6loopback.o: \
+compile socket_v6loopback.c
+	./compile socket_v6loopback.c
+
+clean:
+	rm -f `cat TARGETS`
diff -uNr ucspi-tcp-0.88/TARGETS ucspi-tcp-0.88-ipv6/TARGETS
--- ucspi-tcp-0.88/TARGETS	2000-03-18 16:18:42.000000000 +0100
+++ ucspi-tcp-0.88-ipv6/TARGETS	2005-04-23 12:54:56.881046472 +0200
@@ -169,3 +169,31 @@
 it
 setup
 check
+dns_ip6.o
+dns_ipq6.o
+dns_nd6.o
+dns_sortip6.o
+fmt_xlong.o
+ip6_fmt.o
+ip6_scan.o
+scan_0x.o
+socket_accept6.o
+socket_bind6.o
+socket_conn6.o
+socket_local6.o
+socket_recv6.o
+socket_remote6.o
+socket_send6.o
+socket_tcp6.o
+timeoutconn6.o
+haveip6.h
+remoteinfo6.o
+socket_getifidx.o
+socket_getifname.o
+scan_ip6.o
+scan_xlong.o
+socket_ip4loopback.o
+socket_udp6.o
+socket_v4mappedprefix.o
+socket_v6any.o
+socket_v6loopback.o
diff -uNr ucspi-tcp-0.88/addcr.1 ucspi-tcp-0.88-ipv6/addcr.1
--- ucspi-tcp-0.88/addcr.1	1970-01-01 01:00:00.000000000 +0100
+++ ucspi-tcp-0.88-ipv6/addcr.1	2005-04-23 12:54:56.882046320 +0200
@@ -0,0 +1,22 @@
+.TH addcr 1
+.SH NAME
+addcr \- add a CR before each LF
+.SH SYNOPSIS
+.B addcr
+.SH DESCRIPTION
+.B addcr
+inserts CR at the end of each line of input.
+It does not insert CR at the end of a partial final line.
+.SH COMPATIBILITY
+Some vendors ship
+.B unix2dos
+or
+.B bsd2dos
+tools similar to
+.BR addcr .
+Those tools often blow up on long lines and nulls.
+.B addcr
+has no trouble with long lines and nulls.
+.SH "SEE ALSO"
+delcr(1),
+fixcr(1)
diff -uNr ucspi-tcp-0.88/argv0.1 ucspi-tcp-0.88-ipv6/argv0.1
--- ucspi-tcp-0.88/argv0.1	1970-01-01 01:00:00.000000000 +0100
+++ ucspi-tcp-0.88-ipv6/argv0.1	2005-04-23 12:54:56.883046168 +0200
@@ -0,0 +1,47 @@
+.TH argv0 1
+.SH NAME
+argv0 \- run a program with a specified 0th argument
+.SH SYNOPSIS
+.B argv0
+.I realname
+.I zero
+[
+.I arg ...
+]
+.SH DESCRIPTION
+.B argv0
+runs
+the program stored as
+.I realname
+on disk,
+with the given
+arguments.
+It sets the 0th argument of
+the program to
+.IR zero .
+
+For example,
+
+.EX
+     argv0 /bin/csh -bin/csh
+.EE
+
+runs
+.B /bin/csh
+with a 0th argument of
+.BR -bin/csh .
+.B csh
+will think it is a login shell
+and behave accordingly.
+
+.B argv0
+can be used to run some
+.B inetd
+wrappers under
+.BR tcpserver .
+.SH "SEE ALSO"
+csh(1),
+tcpserver(1),
+execve(2),
+execvp(3),
+inetd(8)
diff -uNr ucspi-tcp-0.88/date@.1 ucspi-tcp-0.88-ipv6/date@.1
--- ucspi-tcp-0.88/date@.1	1970-01-01 01:00:00.000000000 +0100
+++ ucspi-tcp-0.88-ipv6/date@.1	2005-04-23 12:54:56.884046016 +0200
@@ -0,0 +1,32 @@
+.TH date@ 1
+.SH NAME
+date@ \- print the date on a host
+.SH SYNTAX
+.B date@
+[
+.I host
+]
+.SH DESCRIPTION
+.B date@
+connects to TCP port 13 (Daytime) on
+.I host
+and prints any data it receives.
+It removes CR and converts unprintable characters to a visible format.
+
+If
+.I host
+is not supplied,
+.B date@
+connects to the local host.
+
+Some computers respond to port 13 with a human-readable date.
+For example, they may be running
+
+.EX
+     tcpserver 0 13 date &
+.EE
+.SH "SEE ALSO"
+cat(1),
+delcr(1),
+tcpclient(1),
+tcpserver(1)
diff -uNr ucspi-tcp-0.88/delcr.1 ucspi-tcp-0.88-ipv6/delcr.1
--- ucspi-tcp-0.88/delcr.1	1970-01-01 01:00:00.000000000 +0100
+++ ucspi-tcp-0.88-ipv6/delcr.1	2005-04-23 12:54:56.885045864 +0200
@@ -0,0 +1,30 @@
+.TH delcr 1
+.SH NAME
+delcr \- remove a CR before each LF
+.SH SYNOPSIS
+.B delcr
+.SH DESCRIPTION
+.B delcr
+removes a CR at the end of each line of input,
+if a CR is present.
+It also removes a CR at the end of a partial final line.
+
+The pipeline
+
+.EX
+     addcr | delcr
+.EE
+
+prints an exact copy of its input.
+.SH COMPATIBILITY
+Some vendors ship
+.B dos2unix
+or
+.B dos2bsd
+tools similar to
+.BR delcr .
+Those tools often blow up on long lines and nulls.
+.B delcr
+has no trouble with long lines and nulls.
+.SH "SEE ALSO"
+addcr(1)
diff -uNr ucspi-tcp-0.88/dns.h ucspi-tcp-0.88-ipv6/dns.h
--- ucspi-tcp-0.88/dns.h	2000-03-18 16:18:42.000000000 +0100
+++ ucspi-tcp-0.88-ipv6/dns.h	2005-04-23 12:56:40.848241056 +0200
@@ -34,51 +34,60 @@
   unsigned int curserver;
   struct taia deadline;
   unsigned int pos;
-  char *servers;
-  char localip[4];
+  const char *servers;
+  char localip[16];
+  unsigned int scope_id;
   char qtype[2];
 } ;
 
-extern void dns_random_init(char *);
+extern void dns_random_init(const char *);
 extern unsigned int dns_random(unsigned int);
 
 extern void dns_sortip(char *,unsigned int);
+extern void dns_sortip6(char *,unsigned int);
 
 extern void dns_domain_free(char **);
-extern int dns_domain_copy(char **,char *);
-extern unsigned int dns_domain_length(char *);
-extern int dns_domain_equal(char *,char *);
-extern char *dns_domain_suffix(char *,char *);
-extern int dns_domain_fromdot(char **,char *,unsigned int);
-extern int dns_domain_todot_cat(stralloc *,char *);
-
-extern unsigned int dns_packet_copy(char *,unsigned int,unsigned int,char *,unsigned int);
-extern unsigned int dns_packet_getname(char *,unsigned int,unsigned int,char **);
-extern unsigned int dns_packet_skipname(char *,unsigned int,unsigned int);
-extern int dns_packet_nameequal(char *,unsigned int,unsigned int,char *,unsigned int,unsigned int);
+extern int dns_domain_copy(char **,const char *);
+extern unsigned int dns_domain_length(const char *);
+extern int dns_domain_equal(const char *,const char *);
+extern int dns_domain_suffix(const char *,const char *);
+extern unsigned int dns_domain_suffixpos(const char *,const char *);
+extern int dns_domain_fromdot(char **,const char *,unsigned int);
+extern int dns_domain_todot_cat(stralloc *,const char *);
+
+extern unsigned int dns_packet_copy(const char *,unsigned int,unsigned int,char *,unsigned int);
+extern unsigned int dns_packet_getname(const char *,unsigned int,unsigned int,char **);
+extern unsigned int dns_packet_skipname(const char *,unsigned int,unsigned int);
 
-extern int dns_transmit_start(struct dns_transmit *,char *,int,char *,char *,char *);
+extern int dns_transmit_start(struct dns_transmit *,const char *,int,const char *,const char *,const char *);
 extern void dns_transmit_free(struct dns_transmit *);
 extern void dns_transmit_io(struct dns_transmit *,iopause_fd *,struct taia *);
-extern int dns_transmit_get(struct dns_transmit *,iopause_fd *,struct taia *);
+extern int dns_transmit_get(struct dns_transmit *,const iopause_fd *,const struct taia *);
 
 extern int dns_resolvconfip(char *);
-extern int dns_resolve(char *,char *);
+extern int dns_resolve(const char *,const char *);
 extern struct dns_transmit dns_resolve_tx;
 
-extern int dns_ip4_packet(stralloc *,char *,unsigned int);
-extern int dns_ip4(stralloc *,stralloc *);
-extern int dns_name_packet(stralloc *,char *,unsigned int);
-extern void dns_name4_domain(char *,char *);
+extern int dns_ip4_packet(stralloc *,const char *,unsigned int);
+extern int dns_ip4(stralloc *,const stralloc *);
+extern int dns_ip6_packet(stralloc *,const char *,unsigned int);
+extern int dns_ip6(stralloc *,stralloc *);
+extern int dns_name_packet(stralloc *,const char *,unsigned int);
+extern void dns_name4_domain(char *,const char *);
 #define DNS_NAME4_DOMAIN 31
-extern int dns_name4(stralloc *,char *);
-extern int dns_txt_packet(stralloc *,char *,unsigned int);
-extern int dns_txt(stralloc *,stralloc *);
-extern int dns_mx_packet(stralloc *,char *,unsigned int);
-extern int dns_mx(stralloc *,stralloc *);
+extern int dns_name4(stralloc *,const char *);
+extern int dns_txt_packet(stralloc *,const char *,unsigned int);
+extern int dns_txt(stralloc *,const stralloc *);
+extern int dns_mx_packet(stralloc *,const char *,unsigned int);
+extern int dns_mx(stralloc *,const stralloc *);
 
 extern int dns_resolvconfrewrite(stralloc *);
-extern int dns_ip4_qualify_rules(stralloc *,stralloc *,stralloc *,stralloc *);
-extern int dns_ip4_qualify(stralloc *,stralloc *,stralloc *);
+extern int dns_ip4_qualify_rules(stralloc *,stralloc *,const stralloc *,const stralloc *);
+extern int dns_ip4_qualify(stralloc *,stralloc *,const stralloc *);
+extern int dns_ip6_qualify_rules(stralloc *,stralloc *,const stralloc *,const stralloc *);
+extern int dns_ip6_qualify(stralloc *,stralloc *,const stralloc *);
+
+extern int dns_name6_domain(char *,char *);
+#define DNS_NAME6_DOMAIN (4*16+11)
 
 #endif
diff -uNr ucspi-tcp-0.88/dns_dfd.c ucspi-tcp-0.88-ipv6/dns_dfd.c
--- ucspi-tcp-0.88/dns_dfd.c	2000-03-18 16:18:42.000000000 +0100
+++ ucspi-tcp-0.88-ipv6/dns_dfd.c	2005-04-23 12:54:56.887045560 +0200
@@ -1,9 +1,9 @@
-#include "error.h"
-#include "alloc.h"
+#include <stdlib.h>
+#include <errno.h>
 #include "byte.h"
 #include "dns.h"
 
-int dns_domain_fromdot(char **out,char *buf,unsigned int n)
+int dns_domain_fromdot(char **out,const char *buf,unsigned int n)
 {
   char label[63];
   unsigned int labellen = 0; /* <= sizeof label */
@@ -12,7 +12,7 @@
   char ch;
   char *x;
 
-  errno = error_proto;
+  errno = EPROTO;
 
   for (;;) {
     if (!n) break;
@@ -59,11 +59,11 @@
   if (namelen + 1 > sizeof name) return 0;
   name[namelen++] = 0;
 
-  x = alloc(namelen);
+  x = malloc(namelen);
   if (!x) return 0;
   byte_copy(x,namelen,name);
 
-  if (*out) alloc_free(*out);
+  if (*out) free(*out);
   *out = x;
   return 1;
 }
diff -uNr ucspi-tcp-0.88/dns_domain.c ucspi-tcp-0.88-ipv6/dns_domain.c
--- ucspi-tcp-0.88/dns_domain.c	2000-03-18 16:18:42.000000000 +0100
+++ ucspi-tcp-0.88-ipv6/dns_domain.c	2005-04-23 12:54:56.888045408 +0200
@@ -1,16 +1,15 @@
-#include "error.h"
-#include "alloc.h"
+#include <stdlib.h>
 #include "case.h"
 #include "byte.h"
 #include "dns.h"
 
-unsigned int dns_domain_length(char *dn)
+unsigned int dns_domain_length(const char *dn)
 {
-  char *x;
+  const char *x;
   unsigned char c;
 
   x = dn;
-  while (c = *x++)
+  while ((c = *x++))
     x += (unsigned int) c;
   return x - dn;
 }
@@ -18,26 +17,26 @@
 void dns_domain_free(char **out)
 {
   if (*out) {
-    alloc_free(*out);
+    free(*out);
     *out = 0;
   }
 }
 
-int dns_domain_copy(char **out,char *in)
+int dns_domain_copy(char **out,const char *in)
 {
   unsigned int len;
   char *x;
 
   len = dns_domain_length(in);
-  x = alloc(len);
+  x = malloc(len);
   if (!x) return 0;
   byte_copy(x,len,in);
-  if (*out) alloc_free(*out);
+  if (*out) free(*out);
   *out = x;
   return 1;
 }
 
-int dns_domain_equal(char *dn1,char *dn2)
+int dns_domain_equal(const char *dn1,const char *dn2)
 {
   unsigned int len;
 
@@ -48,12 +47,25 @@
   return 1;
 }
 
-char *dns_domain_suffix(char *big,char *little)
+int dns_domain_suffix(const char *big,const char *little)
+{
+  unsigned char c;
+
+  for (;;) {
+    if (dns_domain_equal(big,little)) return 1;
+    c = *big++;
+    if (!c) return 0;
+    big += c;
+  }
+}
+
+unsigned int dns_domain_suffixpos(const char *big,const char *little)
 {
+  const char *orig = big;
   unsigned char c;
 
   for (;;) {
-    if (dns_domain_equal(big,little)) return big;
+    if (dns_domain_equal(big,little)) return big - orig;
     c = *big++;
     if (!c) return 0;
     big += c;
diff -uNr ucspi-tcp-0.88/dns_dtda.c ucspi-tcp-0.88-ipv6/dns_dtda.c
--- ucspi-tcp-0.88/dns_dtda.c	2000-03-18 16:18:42.000000000 +0100
+++ ucspi-tcp-0.88-ipv6/dns_dtda.c	2005-04-23 12:54:56.889045256 +0200
@@ -1,7 +1,7 @@
 #include "stralloc.h"
 #include "dns.h"
 
-int dns_domain_todot_cat(stralloc *out,char *d)
+int dns_domain_todot_cat(stralloc *out,const char *d)
 {
   char ch;
   char ch2;
diff -uNr ucspi-tcp-0.88/dns_ip.c ucspi-tcp-0.88-ipv6/dns_ip.c
--- ucspi-tcp-0.88/dns_ip.c	2000-03-18 16:18:42.000000000 +0100
+++ ucspi-tcp-0.88-ipv6/dns_ip.c	2005-04-23 12:54:56.890045104 +0200
@@ -3,7 +3,7 @@
 #include "byte.h"
 #include "dns.h"
 
-int dns_ip4_packet(stralloc *out,char *buf,unsigned int len)
+int dns_ip4_packet(stralloc *out,const char *buf,unsigned int len)
 {
   unsigned int pos;
   char header[12];
@@ -36,7 +36,7 @@
 
 static char *q = 0;
 
-int dns_ip4(stralloc *out,stralloc *fqdn)
+int dns_ip4(stralloc *out,const stralloc *fqdn)
 {
   unsigned int i;
   char code;
diff -uNr ucspi-tcp-0.88/dns_ip6.c ucspi-tcp-0.88-ipv6/dns_ip6.c
--- ucspi-tcp-0.88/dns_ip6.c	1970-01-01 01:00:00.000000000 +0100
+++ ucspi-tcp-0.88-ipv6/dns_ip6.c	2005-04-23 12:54:56.891044952 +0200
@@ -0,0 +1,103 @@
+#include "stralloc.h"
+#include "uint16.h"
+#include "byte.h"
+#include "dns.h"
+#include "ip4.h"
+#include "ip6.h"
+
+static int dns_ip6_packet_add(stralloc *out,const char *buf,unsigned int len)
+{
+  unsigned int pos;
+  char header[16];
+  uint16 numanswers;
+  uint16 datalen;
+
+  pos = dns_packet_copy(buf,len,0,header,12); if (!pos) return -1;
+  uint16_unpack_big(header + 6,&numanswers);
+  pos = dns_packet_skipname(buf,len,pos); if (!pos) return -1;
+  pos += 4;
+
+  while (numanswers--) {
+    pos = dns_packet_skipname(buf,len,pos); if (!pos) return -1;
+    pos = dns_packet_copy(buf,len,pos,header,10); if (!pos) return -1;
+    uint16_unpack_big(header + 8,&datalen);
+    if (byte_equal(header,2,DNS_T_AAAA)) {
+      if (byte_equal(header + 2,2,DNS_C_IN))
+        if (datalen == 16) {
+	  if (!dns_packet_copy(buf,len,pos,header,16)) return -1;
+	  if (!stralloc_catb(out,header,16)) return -1;
+	}
+    } else if (byte_equal(header,2,DNS_T_A))
+      if (byte_equal(header + 2,2,DNS_C_IN))
+        if (datalen == 4) {
+	  byte_copy(header,12,V4mappedprefix);
+	  if (!dns_packet_copy(buf,len,pos,header+12,4)) return -1;
+	  if (!stralloc_catb(out,header,16)) return -1;
+	}
+    pos += datalen;
+  }
+
+  dns_sortip6(out->s,out->len);
+  return 0;
+}
+
+int dns_ip6_packet(stralloc *out,const char *buf,unsigned int len) {
+  if (!stralloc_copys(out,"")) return -1;
+  return dns_ip6_packet_add(out,buf,len);
+}
+
+static char *q = 0;
+
+int dns_ip6(stralloc *out,stralloc *fqdn)
+{
+  unsigned int i;
+  char code;
+  char ch;
+  char ip[16];
+
+  if (!stralloc_copys(out,"")) return -1;
+  if (!stralloc_readyplus(fqdn,1)) return -1;
+  fqdn->s[fqdn->len]=0;
+  if ((i=scan_ip6(fqdn->s,ip))) {
+    if (fqdn->s[i]) return -1;
+    stralloc_copyb(out,ip,16);
+    return 0;
+  }
+  code = 0;
+  for (i = 0;i <= fqdn->len;++i) {
+    if (i < fqdn->len)
+      ch = fqdn->s[i];
+    else
+      ch = '.';
+
+    if ((ch == '[') || (ch == ']')) continue;
+    if (ch == '.') {
+      if (!stralloc_append(out,&code)) return -1;
+      code = 0;
+      continue;
+    }
+    if ((ch >= '0') && (ch <= '9')) {
+      code *= 10;
+      code += ch - '0';
+      continue;
+    }
+
+    if (!dns_domain_fromdot(&q,fqdn->s,fqdn->len)) return -1;
+    if (!stralloc_copys(out,"")) return -1;
+    if (dns_resolve(q,DNS_T_AAAA) != -1)
+      if (dns_ip6_packet_add(out,dns_resolve_tx.packet,dns_resolve_tx.packetlen) != -1) {
+	dns_transmit_free(&dns_resolve_tx);
+	dns_domain_free(&q);
+      }
+    if (!dns_domain_fromdot(&q,fqdn->s,fqdn->len)) return -1;
+    if (dns_resolve(q,DNS_T_A) != -1)
+      if (dns_ip6_packet_add(out,dns_resolve_tx.packet,dns_resolve_tx.packetlen) != -1) {
+	dns_transmit_free(&dns_resolve_tx);
+	dns_domain_free(&q);
+      }
+    return out->a>0?0:-1;
+  }
+
+  out->len &= ~3;
+  return 0;
+}
diff -uNr ucspi-tcp-0.88/dns_ipq.c ucspi-tcp-0.88-ipv6/dns_ipq.c
--- ucspi-tcp-0.88/dns_ipq.c	2000-03-18 16:18:42.000000000 +0100
+++ ucspi-tcp-0.88-ipv6/dns_ipq.c	2005-04-23 12:54:56.892044800 +0200
@@ -4,7 +4,7 @@
 #include "str.h"
 #include "dns.h"
 
-static int doit(stralloc *work,char *rule)
+static int doit(stralloc *work,const char *rule)
 {
   char ch;
   unsigned int colon;
@@ -30,7 +30,7 @@
   return stralloc_cats(work,rule + colon + 1);
 }
 
-int dns_ip4_qualify_rules(stralloc *out,stralloc *fqdn,stralloc *in,stralloc *rules)
+int dns_ip4_qualify_rules(stralloc *out,stralloc *fqdn,const stralloc *in,const stralloc *rules)
 {
   unsigned int i;
   unsigned int j;
@@ -63,7 +63,7 @@
   }
 }
 
-int dns_ip4_qualify(stralloc *out,stralloc *fqdn,stralloc *in)
+int dns_ip4_qualify(stralloc *out,stralloc *fqdn,const stralloc *in)
 {
   static stralloc rules;
   if (dns_resolvconfrewrite(&rules) == -1) return -1;
diff -uNr ucspi-tcp-0.88/dns_ipq6.c ucspi-tcp-0.88-ipv6/dns_ipq6.c
--- ucspi-tcp-0.88/dns_ipq6.c	1970-01-01 01:00:00.000000000 +0100
+++ ucspi-tcp-0.88-ipv6/dns_ipq6.c	2005-04-23 12:54:56.893044648 +0200
@@ -0,0 +1,72 @@
+#include "stralloc.h"
+#include "case.h"
+#include "byte.h"
+#include "str.h"
+#include "dns.h"
+
+static int doit(stralloc *work,const char *rule)
+{
+  char ch;
+  unsigned int colon;
+  unsigned int prefixlen;
+
+  ch = *rule++;
+  if ((ch != '?') && (ch != '=') && (ch != '*') && (ch != '-')) return 1;
+  colon = str_chr(rule,':');
+  if (!rule[colon]) return 1;
+
+  if (work->len < colon) return 1;
+  prefixlen = work->len - colon;
+  if ((ch == '=') && prefixlen) return 1;
+  if (case_diffb(rule,colon,work->s + prefixlen)) return 1;
+  if (ch == '?') {
+    if (byte_chr(work->s,prefixlen,'.') < prefixlen) return 1;
+    if (byte_chr(work->s,prefixlen,':') < prefixlen) return 1;
+    if (byte_chr(work->s,prefixlen,'[') < prefixlen) return 1;
+    if (byte_chr(work->s,prefixlen,']') < prefixlen) return 1;
+  }
+
+  work->len = prefixlen;
+  if (ch == '-') work->len = 0;
+  return stralloc_cats(work,rule + colon + 1);
+}
+
+int dns_ip6_qualify_rules(stralloc *out,stralloc *fqdn,const stralloc *in,const stralloc *rules)
+{
+  unsigned int i;
+  unsigned int j;
+  unsigned int plus;
+  unsigned int fqdnlen;
+
+  if (!stralloc_copy(fqdn,in)) return -1;
+
+  for (j = i = 0;j < rules->len;++j)
+    if (!rules->s[j]) {
+      if (!doit(fqdn,rules->s + i)) return -1;
+      i = j + 1;
+    }
+
+  fqdnlen = fqdn->len;
+  plus = byte_chr(fqdn->s,fqdnlen,'+');
+  if (plus >= fqdnlen)
+    return dns_ip6(out,fqdn);
+
+  i = plus + 1;
+  for (;;) {
+    j = byte_chr(fqdn->s + i,fqdnlen - i,'+');
+    byte_copy(fqdn->s + plus,j,fqdn->s + i);
+    fqdn->len = plus + j;
+    if (dns_ip6(out,fqdn) == -1) return -1;
+    if (out->len) return 0;
+    i += j;
+    if (i >= fqdnlen) return 0;
+    ++i;
+  }
+}
+
+int dns_ip6_qualify(stralloc *out,stralloc *fqdn,const stralloc *in)
+{
+  static stralloc rules;
+  if (dns_resolvconfrewrite(&rules) == -1) return -1;
+  return dns_ip6_qualify_rules(out,fqdn,in,&rules);
+}
diff -uNr ucspi-tcp-0.88/dns_name.c ucspi-tcp-0.88-ipv6/dns_name.c
--- ucspi-tcp-0.88/dns_name.c	2000-03-18 16:18:42.000000000 +0100
+++ ucspi-tcp-0.88-ipv6/dns_name.c	2005-04-23 12:54:56.894044496 +0200
@@ -2,10 +2,11 @@
 #include "uint16.h"
 #include "byte.h"
 #include "dns.h"
+#include "ip6.h"
 
 static char *q = 0;
 
-int dns_name_packet(stralloc *out,char *buf,unsigned int len)
+int dns_name_packet(stralloc *out,const char *buf,unsigned int len)
 {
   unsigned int pos;
   char header[12];
@@ -35,7 +36,7 @@
   return 0;
 }
 
-int dns_name4(stralloc *out,char ip[4])
+int dns_name4(stralloc *out,const char ip[4])
 {
   char name[DNS_NAME4_DOMAIN];
 
@@ -46,3 +47,17 @@
   dns_domain_free(&q);
   return 0;
 }
+
+int dns_name6(stralloc *out,char ip[16])
+{
+  char name[DNS_NAME6_DOMAIN];
+
+  if (ip6_isv4mapped(ip))
+    return dns_name4(out,ip+12);
+  dns_name6_domain(name,ip);
+  if (dns_resolve(name,DNS_T_PTR) == -1) return -1;
+  if (dns_name_packet(out,dns_resolve_tx.packet,dns_resolve_tx.packetlen) == -1) return -1;
+  dns_transmit_free(&dns_resolve_tx);
+  dns_domain_free(&q);
+  return 0;
+}
diff -uNr ucspi-tcp-0.88/dns_nd.c ucspi-tcp-0.88-ipv6/dns_nd.c
--- ucspi-tcp-0.88/dns_nd.c	2000-03-18 16:18:42.000000000 +0100
+++ ucspi-tcp-0.88-ipv6/dns_nd.c	2005-04-23 12:54:56.895044344 +0200
@@ -2,7 +2,7 @@
 #include "fmt.h"
 #include "dns.h"
 
-void dns_name4_domain(char name[DNS_NAME4_DOMAIN],char ip[4])
+void dns_name4_domain(char name[DNS_NAME4_DOMAIN],const char ip[4])
 {
   unsigned int namelen;
   unsigned int i;
diff -uNr ucspi-tcp-0.88/dns_nd6.c ucspi-tcp-0.88-ipv6/dns_nd6.c
--- ucspi-tcp-0.88/dns_nd6.c	1970-01-01 01:00:00.000000000 +0100
+++ ucspi-tcp-0.88-ipv6/dns_nd6.c	2005-04-23 16:56:43.173782872 +0200
@@ -0,0 +1,28 @@
+#include "byte.h"
+#include "fmt.h"
+#include "dns.h"
+
+/* RFC1886:
+ *   4321:0:1:2:3:4:567:89ab
+ * ->
+ *   b.a.9.8.7.6.5.0.4.0.0.0.3.0.0.0.2.0.0.0.1.0.0.0.0.0.0.0.1.2.3.4.IP6.INT.
+ */
+
+static inline char tohex(char c) {
+  return c>=10?c-10+'a':c+'0';
+}
+
+int dns_name6_domain(char name[DNS_NAME6_DOMAIN],char ip[16])
+{
+  unsigned int j;
+
+  for (j=0; j<16; j++) {
+    name[j*4]=1;
+    name[j*4+1]=tohex(ip[15-j] & 15);
+    name[j*4+2]=1;
+    name[j*4+3]=tohex((unsigned char)ip[15-j] >> 4);
+  }
+  byte_copy(name + 4*16,10,"\3ip6\4arpa\0");
+  return 4*16+10;
+}
+
diff -uNr ucspi-tcp-0.88/dns_packet.c ucspi-tcp-0.88-ipv6/dns_packet.c
--- ucspi-tcp-0.88/dns_packet.c	2000-03-18 16:18:42.000000000 +0100
+++ ucspi-tcp-0.88-ipv6/dns_packet.c	2005-04-23 12:54:56.896044192 +0200
@@ -2,20 +2,20 @@
 DNS should have used LZ77 instead of its own sophomoric compression algorithm.
 */
 
-#include "error.h"
+#include <errno.h>
 #include "dns.h"
 
-unsigned int dns_packet_copy(char *buf,unsigned int len,unsigned int pos,char *out,unsigned int outlen)
+unsigned int dns_packet_copy(const char *buf,unsigned int len,unsigned int pos,char *out,unsigned int outlen)
 {
   while (outlen) {
-    if (pos >= len) { errno = error_proto; return 0; }
+    if (pos >= len) { errno = EPROTO; return 0; }
     *out = buf[pos++];
     ++out; --outlen;
   }
   return pos;
 }
 
-unsigned int dns_packet_skipname(char *buf,unsigned int len,unsigned int pos)
+unsigned int dns_packet_skipname(const char *buf,unsigned int len,unsigned int pos)
 {
   unsigned char ch;
 
@@ -28,11 +28,11 @@
     pos += ch;
   }
 
-  errno = error_proto;
+  errno = EPROTO;
   return 0;
 }
 
-unsigned int dns_packet_getname(char *buf,unsigned int len,unsigned int pos,char **d)
+unsigned int dns_packet_getname(const char *buf,unsigned int len,unsigned int pos,char **d)
 {
   unsigned int loop = 0;
   unsigned int state = 0;
@@ -72,6 +72,6 @@
   return pos;
 
   PROTO:
-  errno = error_proto;
+  errno = EPROTO;
   return 0;
 }
diff -uNr ucspi-tcp-0.88/dns_random.c ucspi-tcp-0.88-ipv6/dns_random.c
--- ucspi-tcp-0.88/dns_random.c	2000-03-18 16:18:42.000000000 +0100
+++ ucspi-tcp-0.88-ipv6/dns_random.c	2005-04-23 12:54:56.897044040 +0200
@@ -1,3 +1,4 @@
+#include <unistd.h>
 #include "dns.h"
 #include "taia.h"
 #include "uint32.h"
@@ -29,7 +30,7 @@
   }
 }
 
-void dns_random_init(char data[128])
+void dns_random_init(const char data[128])
 {
   int i;
   struct taia t;
diff -uNr ucspi-tcp-0.88/dns_rcip.c ucspi-tcp-0.88-ipv6/dns_rcip.c
--- ucspi-tcp-0.88/dns_rcip.c	2000-03-18 16:18:42.000000000 +0100
+++ ucspi-tcp-0.88-ipv6/dns_rcip.c	2005-04-23 12:54:56.898043888 +0200
@@ -2,12 +2,13 @@
 #include "openreadclose.h"
 #include "byte.h"
 #include "ip4.h"
-#include "env.h"
+#include "ip6.h"
 #include "dns.h"
+#include "env.h"
 
 static stralloc data = {0};
 
-static int init(char ip[64])
+static int init(char ip[256])
 {
   int i;
   int j;
@@ -16,15 +17,16 @@
 
   x = env_get("DNSCACHEIP");
   if (x)
-    while (iplen <= 60)
+    while (iplen <= 60) {
       if (*x == '.')
 	++x;
       else {
-        i = ip4_scan(x,ip + iplen);
+        i = scan_ip6(x,ip + iplen);
 	if (!i) break;
 	x += i;
-	iplen += 4;
+	iplen += 16;
       }
+    }
 
   if (!iplen) {
     i = openreadclose("/etc/resolv.conf",&data,64);
@@ -39,8 +41,9 @@
             while ((data.s[i] == ' ') || (data.s[i] == '\t'))
               ++i;
             if (iplen <= 60)
-              if (ip4_scan(data.s + i,ip + iplen))
-                iplen += 4;
+              if (scan_ip6(data.s + i,ip + iplen)) {
+                iplen += 16;
+	      }
           }
           i = j + 1;
         }
@@ -48,19 +51,19 @@
   }
 
   if (!iplen) {
-    byte_copy(ip,4,"\177\0\0\1");
-    iplen = 4;
+    byte_copy(ip,16,"\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\1");
+    iplen = 16;
   }
-  byte_zero(ip + iplen,64 - iplen);
+  byte_zero(ip + iplen,256 - iplen);
   return 0;
 }
 
 static int ok = 0;
 static unsigned int uses;
 static struct taia deadline;
-static char ip[64]; /* defined if ok */
+static char ip[256]; /* defined if ok */
 
-int dns_resolvconfip(char s[64])
+int dns_resolvconfip(char s[256])
 {
   struct taia now;
 
@@ -77,6 +80,6 @@
   }
 
   --uses;
-  byte_copy(s,64,ip);
+  byte_copy(s,256,ip);
   return 0;
 }
diff -uNr ucspi-tcp-0.88/dns_rcrw.c ucspi-tcp-0.88-ipv6/dns_rcrw.c
--- ucspi-tcp-0.88/dns_rcrw.c	2000-03-18 16:18:42.000000000 +0100
+++ ucspi-tcp-0.88-ipv6/dns_rcrw.c	2005-04-23 12:54:56.899043736 +0200
@@ -1,16 +1,17 @@
+#include <unistd.h>
 #include "taia.h"
-#include "env.h"
 #include "byte.h"
 #include "str.h"
 #include "openreadclose.h"
 #include "dns.h"
+#include "env.h"
 
 static stralloc data = {0};
 
 static int init(stralloc *rules)
 {
   char host[256];
-  char *x;
+  const char *x;
   int i;
   int j;
   int k;
diff -uNr ucspi-tcp-0.88/dns_resolve.c ucspi-tcp-0.88-ipv6/dns_resolve.c
--- ucspi-tcp-0.88/dns_resolve.c	2000-03-18 16:18:42.000000000 +0100
+++ ucspi-tcp-0.88-ipv6/dns_resolve.c	2005-04-23 12:54:56.900043584 +0200
@@ -2,19 +2,20 @@
 #include "taia.h"
 #include "byte.h"
 #include "dns.h"
+#include "ip6.h"
 
 struct dns_transmit dns_resolve_tx = {0};
 
-int dns_resolve(char *q,char qtype[2])
+int dns_resolve(const char *q,const char qtype[2])
 {
   struct taia stamp;
   struct taia deadline;
-  char servers[64];
+  char servers[256];
   iopause_fd x[1];
   int r;
 
   if (dns_resolvconfip(servers) == -1) return -1;
-  if (dns_transmit_start(&dns_resolve_tx,servers,1,q,qtype,"\0\0\0\0") == -1) return -1;
+  if (dns_transmit_start(&dns_resolve_tx,servers,1,q,qtype,V6any) == -1) return -1;
 
   for (;;) {
     taia_now(&stamp);
diff -uNr ucspi-tcp-0.88/dns_sortip6.c ucspi-tcp-0.88-ipv6/dns_sortip6.c
--- ucspi-tcp-0.88/dns_sortip6.c	1970-01-01 01:00:00.000000000 +0100
+++ ucspi-tcp-0.88-ipv6/dns_sortip6.c	2005-04-23 12:54:56.901043432 +0200
@@ -0,0 +1,20 @@
+#include "byte.h"
+#include "dns.h"
+
+/* XXX: sort servers by configurable notion of closeness? */
+/* XXX: pay attention to competence of each server? */
+
+void dns_sortip6(char *s,unsigned int n)
+{
+  unsigned int i;
+  char tmp[16];
+
+  n >>= 4;
+  while (n > 1) {
+    i = dns_random(n);
+    --n;
+    byte_copy(tmp,16,s + (i << 4));
+    byte_copy(s + (i << 4),16,s + (n << 4));
+    byte_copy(s + (n << 4),16,tmp);
+  }
+}
diff -uNr ucspi-tcp-0.88/dns_transmit.c ucspi-tcp-0.88-ipv6/dns_transmit.c
--- ucspi-tcp-0.88/dns_transmit.c	2000-03-18 16:18:42.000000000 +0100
+++ ucspi-tcp-0.88-ipv6/dns_transmit.c	2005-04-23 12:54:56.902043280 +0200
@@ -1,12 +1,15 @@
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <unistd.h>
+#include <stdlib.h>
 #include "socket.h"
-#include "alloc.h"
-#include "error.h"
+#include <errno.h>
 #include "byte.h"
-#include "readwrite.h"
 #include "uint16.h"
 #include "dns.h"
+#include "ip6.h"
 
-static int serverwantstcp(char *buf,unsigned int len)
+static int serverwantstcp(const char *buf,unsigned int len)
 {
   char out[12];
 
@@ -15,7 +18,7 @@
   return 0;
 }
 
-static int serverfailed(char *buf,unsigned int len)
+static int serverfailed(const char *buf,unsigned int len)
 {
   char out[12];
   unsigned int rcode;
@@ -23,11 +26,11 @@
   if (!dns_packet_copy(buf,len,0,out,12)) return 1;
   rcode = out[3];
   rcode &= 15;
-  if (rcode && (rcode != 3)) { errno = error_again; return 1; }
+  if (rcode && (rcode != 3)) { errno = EAGAIN; return 1; }
   return 0;
 }
 
-static int irrelevant(struct dns_transmit *d,char *buf,unsigned int len)
+static int irrelevant(const struct dns_transmit *d,const char *buf,unsigned int len)
 {
   char out[12];
   char *dn;
@@ -40,8 +43,8 @@
 
   dn = 0;
   pos = dns_packet_getname(buf,len,pos,&dn); if (!pos) return 1;
-  if (!dns_domain_equal(dn,d->query + 14)) { alloc_free(dn); return 1; }
-  alloc_free(dn);
+  if (!dns_domain_equal(dn,d->query + 14)) { free(dn); return 1; }
+  free(dn);
 
   pos = dns_packet_copy(buf,len,pos,out,4); if (!pos) return 1;
   if (byte_diff(out,2,d->qtype)) return 1;
@@ -53,14 +56,14 @@
 static void packetfree(struct dns_transmit *d)
 {
   if (!d->packet) return;
-  alloc_free(d->packet);
+  free(d->packet);
   d->packet = 0;
 }
 
 static void queryfree(struct dns_transmit *d)
 {
   if (!d->query) return;
-  alloc_free(d->query);
+  free(d->query);
   d->query = 0;
 }
 
@@ -83,9 +86,9 @@
   int j;
 
   for (j = 0;j < 10;++j)
-    if (socket_bind4(d->s1 - 1,d->localip,1025 + dns_random(64510)) == 0)
+    if (socket_bind6(d->s1 - 1,d->localip,1025 + dns_random(64510),d->scope_id) == 0)
       return 0;
-  if (socket_bind4(d->s1 - 1,d->localip,0) == 0)
+  if (socket_bind6(d->s1 - 1,d->localip,0,d->scope_id) == 0)
     return 0;
   return -1;
 }
@@ -94,22 +97,22 @@
 
 static int thisudp(struct dns_transmit *d)
 {
-  char *ip;
+  const char *ip;
 
   socketfree(d);
 
   while (d->udploop < 4) {
     for (;d->curserver < 16;++d->curserver) {
-      ip = d->servers + 4 * d->curserver;
-      if (byte_diff(ip,4,"\0\0\0\0")) {
+      ip = d->servers + 16 * d->curserver;
+      if (byte_diff(ip,16,V6any)) {
 	d->query[2] = dns_random(256);
 	d->query[3] = dns_random(256);
   
-        d->s1 = 1 + socket_udp();
+        d->s1 = 1 + socket_udp6();
         if (!d->s1) { dns_transmit_free(d); return -1; }
 	if (randombind(d) == -1) { dns_transmit_free(d); return -1; }
 
-        if (socket_connect4(d->s1 - 1,ip,53) == 0)
+        if (socket_connect6(d->s1 - 1,ip,53,d->scope_id) == 0)
           if (send(d->s1 - 1,d->query + 2,d->querylen - 2,0) == d->querylen - 2) {
             struct taia now;
             taia_now(&now);
@@ -145,29 +148,29 @@
 static int thistcp(struct dns_transmit *d)
 {
   struct taia now;
-  char *ip;
+  const char *ip;
 
   socketfree(d);
   packetfree(d);
 
   for (;d->curserver < 16;++d->curserver) {
-    ip = d->servers + 4 * d->curserver;
-    if (byte_diff(ip,4,"\0\0\0\0")) {
+    ip = d->servers + 16 * d->curserver;
+    if (byte_diff(ip,16,V6any)) {
       d->query[2] = dns_random(256);
       d->query[3] = dns_random(256);
 
-      d->s1 = 1 + socket_tcp();
+      d->s1 = 1 + socket_tcp6();
       if (!d->s1) { dns_transmit_free(d); return -1; }
       if (randombind(d) == -1) { dns_transmit_free(d); return -1; }
   
       taia_now(&now);
       taia_uint(&d->deadline,10);
       taia_add(&d->deadline,&d->deadline,&now);
-      if (socket_connect4(d->s1 - 1,ip,53) == 0) {
+      if (socket_connect6(d->s1 - 1,ip,53,d->scope_id) == 0) {
         d->tcpstate = 2;
         return 0;
       }
-      if ((errno == error_inprogress) || (errno == error_wouldblock)) {
+      if ((errno == EINPROGRESS) || (errno == EWOULDBLOCK)) {
         d->tcpstate = 1;
         return 0;
       }
@@ -191,16 +194,16 @@
   return thistcp(d);
 }
 
-int dns_transmit_start(struct dns_transmit *d,char servers[64],int flagrecursive,char *q,char qtype[2],char localip[4])
+int dns_transmit_start(struct dns_transmit *d,const char servers[256],int flagrecursive,const char *q,const char qtype[2],const char localip[16])
 {
   unsigned int len;
 
   dns_transmit_free(d);
-  errno = error_io;
+  errno = EIO;
 
   len = dns_domain_length(q);
   d->querylen = len + 18;
-  d->query = alloc(d->querylen);
+  d->query = malloc(d->querylen);
   if (!d->query) return -1;
 
   uint16_pack_big(d->query,len + 16);
@@ -211,7 +214,7 @@
 
   byte_copy(d->qtype,2,qtype);
   d->servers = servers;
-  byte_copy(d->localip,4,localip);
+  byte_copy(d->localip,16,localip);
 
   d->udploop = flagrecursive ? 1 : 0;
 
@@ -236,19 +239,19 @@
     *deadline = d->deadline;
 }
 
-int dns_transmit_get(struct dns_transmit *d,iopause_fd *x,struct taia *when)
+int dns_transmit_get(struct dns_transmit *d,const iopause_fd *x,const struct taia *when)
 {
   char udpbuf[513];
   unsigned char ch;
   int r;
   int fd;
 
-  errno = error_io;
+  errno = EIO;
   fd = d->s1 - 1;
 
   if (!x->revents) {
     if (taia_less(when,&d->deadline)) return 0;
-    errno = error_timeout;
+    errno = ETIMEDOUT;
     if (d->tcpstate == 0) return nextudp(d);
     return nexttcp(d);
   }
@@ -260,7 +263,7 @@
 */
     r = recv(fd,udpbuf,sizeof udpbuf,0);
     if (r <= 0) {
-      if (d->udploop == 2) return 0;
+      if (errno == ECONNREFUSED) if (d->udploop == 2) return 0;
       return nextudp(d);
     }
     if (r + 1 > sizeof udpbuf) return 0;
@@ -274,7 +277,7 @@
     socketfree(d);
 
     d->packetlen = r;
-    d->packet = alloc(d->packetlen);
+    d->packet = malloc(d->packetlen);
     if (!d->packet) { dns_transmit_free(d); return -1; }
     byte_copy(d->packet,d->packetlen,udpbuf);
     queryfree(d);
@@ -334,7 +337,7 @@
     d->packetlen += ch;
     d->tcpstate = 5;
     d->pos = 0;
-    d->packet = alloc(d->packetlen);
+    d->packet = malloc(d->packetlen);
     if (!d->packet) { dns_transmit_free(d); return -1; }
     return 0;
   }
diff -uNr ucspi-tcp-0.88/dns_txt.c ucspi-tcp-0.88-ipv6/dns_txt.c
--- ucspi-tcp-0.88/dns_txt.c	2000-03-18 16:18:42.000000000 +0100
+++ ucspi-tcp-0.88-ipv6/dns_txt.c	2005-04-23 12:54:56.903043128 +0200
@@ -3,7 +3,7 @@
 #include "byte.h"
 #include "dns.h"
 
-int dns_txt_packet(stralloc *out,char *buf,unsigned int len)
+int dns_txt_packet(stralloc *out,const char *buf,unsigned int len)
 {
   unsigned int pos;
   char header[12];
@@ -48,7 +48,7 @@
 
 static char *q = 0;
 
-int dns_txt(stralloc *out,stralloc *fqdn)
+int dns_txt(stralloc *out,const stralloc *fqdn)
 {
   if (!dns_domain_fromdot(&q,fqdn->s,fqdn->len)) return -1;
   if (dns_resolve(q,DNS_T_TXT) == -1) return -1;
diff -uNr ucspi-tcp-0.88/finger@.1 ucspi-tcp-0.88-ipv6/finger@.1
--- ucspi-tcp-0.88/finger@.1	1970-01-01 01:00:00.000000000 +0100
+++ ucspi-tcp-0.88-ipv6/finger@.1	2005-04-23 12:54:56.903043128 +0200
@@ -0,0 +1,45 @@
+.TH finger@ 1
+.SH NAME
+finger@ \- get user information from a host
+.SH SYNTAX
+.B finger@
+[
+.I host
+[
+.I user
+]
+]
+.SH DESCRIPTION
+.B finger@
+connects to TCP port 79 (Finger) on
+.IR host ,
+sends
+.I user
+(with an extra CR)
+to
+.IR host ,
+and prints any data it receives.
+It removes CR and converts unprintable characters to a visible format.
+Some computers respond to port 79 with information about
+.IR user .
+
+If
+.I user
+is not supplied,
+.B finger@
+sends a blank line to
+.IR host .
+Some computers respond with information about
+all the users who are logged in.
+
+If
+.I host
+is not supplied,
+.B finger@
+connects to the local host.
+.SH "SEE ALSO"
+addcr(1),
+cat(1),
+delcr(1),
+finger(1),
+tcpclient(1)
diff -uNr ucspi-tcp-0.88/fixcr.1 ucspi-tcp-0.88-ipv6/fixcr.1
--- ucspi-tcp-0.88/fixcr.1	1970-01-01 01:00:00.000000000 +0100
+++ ucspi-tcp-0.88-ipv6/fixcr.1	2005-04-23 12:54:56.904042976 +0200
@@ -0,0 +1,11 @@
+.TH fixcr 1
+.SH NAME
+fixcr \- make sure that there is a CR before each LF
+.SH SYNOPSIS
+.B fixcr
+.SH DESCRIPTION
+.B fixcr
+inserts CR at the end of each line of input where a CR is not already present.
+It does not insert CR at the end of a partial final line.
+.SH "SEE ALSO"
+addcr(1)
diff -uNr ucspi-tcp-0.88/fmt_xlong.c ucspi-tcp-0.88-ipv6/fmt_xlong.c
--- ucspi-tcp-0.88/fmt_xlong.c	1970-01-01 01:00:00.000000000 +0100
+++ ucspi-tcp-0.88-ipv6/fmt_xlong.c	2005-04-23 12:54:56.905042824 +0200
@@ -0,0 +1,22 @@
+#include "fmt.h"
+
+char tohex(char num) {
+  if (num<10)
+    return num+'0';
+  else if (num<16)
+    return num-10+'a';
+  else
+    return -1;
+}
+
+unsigned int fmt_xlong(register char *s,register unsigned long u)
+{
+  register unsigned int len; register unsigned long q;
+  len = 1; q = u;
+  while (q > 15) { ++len; q /= 16; }
+  if (s) {
+    s += len;
+    do { *--s = tohex(u % 16); u /= 16; } while(u); /* handles u == 0 */
+  }
+  return len;
+}
diff -uNr ucspi-tcp-0.88/fnord ucspi-tcp-0.88-ipv6/fnord
--- ucspi-tcp-0.88/fnord	1970-01-01 01:00:00.000000000 +0100
+++ ucspi-tcp-0.88-ipv6/fnord	2005-04-23 12:54:56.906042672 +0200
@@ -0,0 +1,2 @@
+127.0.0.1:allow
+:deny
diff -uNr ucspi-tcp-0.88/haveip6.h1 ucspi-tcp-0.88-ipv6/haveip6.h1
--- ucspi-tcp-0.88/haveip6.h1	1970-01-01 01:00:00.000000000 +0100
+++ ucspi-tcp-0.88-ipv6/haveip6.h1	2005-04-23 12:54:56.906042672 +0200
@@ -0,0 +1 @@
+
diff -uNr ucspi-tcp-0.88/haveip6.h2 ucspi-tcp-0.88-ipv6/haveip6.h2
--- ucspi-tcp-0.88/haveip6.h2	1970-01-01 01:00:00.000000000 +0100
+++ ucspi-tcp-0.88-ipv6/haveip6.h2	2005-04-23 12:54:56.907042520 +0200
@@ -0,0 +1 @@
+#define LIBC_HAS_IP6 1
diff -uNr ucspi-tcp-0.88/hier.c ucspi-tcp-0.88-ipv6/hier.c
--- ucspi-tcp-0.88/hier.c	2000-03-18 16:18:42.000000000 +0100
+++ ucspi-tcp-0.88-ipv6/hier.c	2005-04-23 12:54:56.908042368 +0200
@@ -4,6 +4,9 @@
 {
   h(auto_home,-1,-1,02755);
   d(auto_home,"bin",-1,-1,02755);
+  d(auto_home,"man",-1,-1,02755);
+  d(auto_home,"man/man1",-1,-1,02755);
+  d(auto_home,"man/man5",-1,-1,02755);
 
   c(auto_home,"bin","tcpserver",-1,-1,0755);
   c(auto_home,"bin","tcprules",-1,-1,0755);
@@ -22,4 +25,20 @@
   c(auto_home,"bin","delcr",-1,-1,0755);
   c(auto_home,"bin","fixcrio",-1,-1,0755);
   c(auto_home,"bin","rblsmtpd",-1,-1,0755);
+
+  c(auto_home,"man/man1","tcpclient.1",-1,-1,0644);
+  c(auto_home,"man/man1","tcpserver.1",-1,-1,0644);
+  c(auto_home,"man/man1","tcprules.1",-1,-1,0644);
+  c(auto_home,"man/man1","tcprulescheck.1",-1,-1,0644);
+  c(auto_home,"man/man1","fixcr.1",-1,-1,0644);
+  c(auto_home,"man/man1","addcr.1",-1,-1,0644);
+  c(auto_home,"man/man1","delcr.1",-1,-1,0644);
+  c(auto_home,"man/man1","who@.1",-1,-1,0644);
+  c(auto_home,"man/man1","date@.1",-1,-1,0644);
+  c(auto_home,"man/man1","finger@.1",-1,-1,0644);
+  c(auto_home,"man/man1","http@.1",-1,-1,0644);
+  c(auto_home,"man/man1","mconnect.1",-1,-1,0644);
+  c(auto_home,"man/man1","argv0.1",-1,-1,0644);
+  c(auto_home,"man/man1","recordio.1",-1,-1,0644);
+  c(auto_home,"man/man5","tcp-environ.5",-1,-1,0644);
 }
diff -uNr ucspi-tcp-0.88/http@.1 ucspi-tcp-0.88-ipv6/http@.1
--- ucspi-tcp-0.88/http@.1	1970-01-01 01:00:00.000000000 +0100
+++ ucspi-tcp-0.88-ipv6/http@.1	2005-04-23 12:54:56.909042216 +0200
@@ -0,0 +1,52 @@
+.TH http@ 1
+.SH NAME
+http@ \- get a web page from a host through HTTP
+.SH SYNTAX
+.B http@
+[
+.I host
+[
+.I page
+[
+.I port
+]
+]
+]
+.SH DESCRIPTION
+.B http@
+connects to
+.I port
+on
+.IR host ,
+sends
+.B GET /\fIpage
+(with an extra CR)
+to
+.IR host ,
+and prints any data it receives,
+removing CR from the end of each line.
+
+If
+.I port
+is not supplied,
+.B http@
+uses port 80 (HTTP).
+
+If
+.I page
+is not supplied,
+.B http@
+sends
+.B GET /
+to
+.IR host .
+
+If
+.I host
+is not supplied,
+.B http@
+connects to the local host.
+.SH "SEE ALSO"
+addcr(1),
+delcr(1),
+tcpclient(1)
diff -uNr ucspi-tcp-0.88/ip4.h ucspi-tcp-0.88-ipv6/ip4.h
--- ucspi-tcp-0.88/ip4.h	2000-03-18 16:18:42.000000000 +0100
+++ ucspi-tcp-0.88-ipv6/ip4.h	2005-04-23 12:54:56.909042216 +0200
@@ -6,4 +6,6 @@
 
 #define IP4_FMT 20
 
+extern const char ip4loopback[4]; /* = {127,0,0,1}; */
+
 #endif
diff -uNr ucspi-tcp-0.88/ip6.h ucspi-tcp-0.88-ipv6/ip6.h
--- ucspi-tcp-0.88/ip6.h	1970-01-01 01:00:00.000000000 +0100
+++ ucspi-tcp-0.88-ipv6/ip6.h	2005-04-23 12:54:56.910042064 +0200
@@ -0,0 +1,28 @@
+#ifndef IP6_H
+#define IP6_H
+
+#include "byte.h"
+
+extern unsigned int scan_ip6(const char *src,char *ip);
+extern unsigned int fmt_ip6(char *dest,const char *ip);
+
+extern unsigned int scan_ip6_flat(const char *src,char *);
+extern unsigned int fmt_ip6_flat(char *dest,const char *);
+
+/*
+ ip6 address syntax: (h = hex digit), no leading '0' required
+   1. hhhh:hhhh:hhhh:hhhh:hhhh:hhhh:hhhh:hhhh
+   2. any number of 0000 may be abbreviated as "::", but only once
+ flat ip6 address syntax:
+   hhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhh
+ */
+
+#define IP6_FMT 40
+
+extern const unsigned char V4mappedprefix[12]; /*={0,0,0,0,0,0,0,0,0,0,0xff,0xff}; */
+extern const unsigned char V6loopback[16]; /*={0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1}; */
+extern const unsigned char V6any[16]; /*={0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0}; */
+
+#define ip6_isv4mapped(ip) (byte_equal(ip,12,V4mappedprefix))
+
+#endif
diff -uNr ucspi-tcp-0.88/ip6_fmt.c ucspi-tcp-0.88-ipv6/ip6_fmt.c
--- ucspi-tcp-0.88/ip6_fmt.c	1970-01-01 01:00:00.000000000 +0100
+++ ucspi-tcp-0.88-ipv6/ip6_fmt.c	2005-04-23 12:54:56.911041912 +0200
@@ -0,0 +1,62 @@
+#include "fmt.h"
+#include "byte.h"
+#include "ip4.h"
+#include "ip6.h"
+
+unsigned int ip6_fmt(char *s,char ip[16])
+{
+  unsigned int len;
+  unsigned int i;
+  unsigned int temp;
+  unsigned int compressing;
+  int j;
+
+  len = 0; compressing = 0;
+  for (j=0; j<16; j+=2) {
+    if (j==12 && ip6_isv4mapped(ip)) {
+      temp=ip4_fmt(s,ip+12);
+      len+=temp;
+      s+=temp;
+      break;
+    }
+    temp = ((unsigned long) (unsigned char) ip[j] << 8) +
+            (unsigned long) (unsigned char) ip[j+1];
+    if (temp == 0) {
+      if (!compressing) {
+	compressing=1;
+	if (j==0) {
+	  *s=':'; s+=1; ++len;
+	}
+      }
+    } else {
+      if (compressing) {
+	compressing=0;
+	*s=':'; s+=1; ++len;
+      }
+      i = fmt_xlong(s,temp); len += i; if (s) s += i;
+      if (s && j<14) *s++ = ':'; ++len;
+    }
+  }
+
+  if (s) *s=0;
+  return len;
+}
+
+static char tohex(char num) {
+  if (num<10)
+    return num+'0';
+  else if (num<16)
+    return num-10+'a';
+  else
+    return -1;
+}
+
+unsigned int ip6_fmt_flat(char *s,char ip[16])
+{
+  int i;
+  for (i=0; i<16; i++) {
+    *s++=tohex((unsigned char)ip[i] >> 4);
+    *s++=tohex((unsigned char)ip[i] & 15);
+  }
+  return 32;
+}
diff -uNr ucspi-tcp-0.88/mconnect.1 ucspi-tcp-0.88-ipv6/mconnect.1
--- ucspi-tcp-0.88/mconnect.1	1970-01-01 01:00:00.000000000 +0100
+++ ucspi-tcp-0.88-ipv6/mconnect.1	2005-04-23 12:54:56.911041912 +0200
@@ -0,0 +1,36 @@
+.TH mconnect 1
+.SH NAME
+mconnect \- connect to the SMTP server on a host
+.SH SYNTAX
+.B mconnect
+[
+.I host
+[
+.I port
+]
+]
+.SH DESCRIPTION
+.B mconnect
+connects to
+.I port
+on
+.IR host .
+It sends its input to
+.IR host ,
+adding a CR to each line.
+Meanwhile it prints anything it receives from
+.IR host .
+
+If
+.I port
+is not supplied,
+.B mconnect
+uses port 25 (SMTP).
+
+If
+.I host
+is not supplied,
+.B mconnect
+connects to the local host.
+.SH "SEE ALSO"
+tcpclient(1)
diff -uNr ucspi-tcp-0.88/old-rules.c ucspi-tcp-0.88-ipv6/old-rules.c
--- ucspi-tcp-0.88/old-rules.c	1970-01-01 01:00:00.000000000 +0100
+++ ucspi-tcp-0.88-ipv6/old-rules.c	2005-04-23 12:54:56.912041760 +0200
@@ -0,0 +1,101 @@
+#include "alloc.h"
+#include "stralloc.h"
+#include "open.h"
+#include "cdb.h"
+#include "rules.h"
+
+stralloc rules_name = {0};
+
+static struct cdb c;
+
+static int dorule(void (*callback)(char *,unsigned int))
+{
+  char *data;
+  unsigned int datalen;
+
+  switch(cdb_find(&c,rules_name.s,rules_name.len)) {
+    case -1: return -1;
+    case 0: return 0;
+  }
+
+  datalen = cdb_datalen(&c);
+  data = alloc(datalen);
+  if (!data) return -1;
+  if (cdb_read(&c,data,datalen,cdb_datapos(&c)) == -1) {
+    alloc_free(data);
+    return -1;
+  }
+
+  callback(data,datalen);
+  alloc_free(data);
+  return 1;
+}
+
+static int doit(void (*callback)(char *,unsigned int),char *ip,char *host,char *info)
+{
+  int r;
+
+  if (info) {
+    if (!stralloc_copys(&rules_name,info)) return -1;
+    if (!stralloc_cats(&rules_name,"@")) return -1;
+    if (!stralloc_cats(&rules_name,ip)) return -1;
+    r = dorule(callback);
+    if (r) return r;
+
+    if (host) {
+      if (!stralloc_copys(&rules_name,info)) return -1;
+      if (!stralloc_cats(&rules_name,"@=")) return -1;
+      if (!stralloc_cats(&rules_name,host)) return -1;
+      r = dorule(callback);
+      if (r) return r;
+    }
+  }
+
+  if (!stralloc_copys(&rules_name,ip)) return -1;
+  r = dorule(callback);
+  if (r) return r;
+
+  if (host) {
+    if (!stralloc_copys(&rules_name,"=")) return -1;
+    if (!stralloc_cats(&rules_name,host)) return -1;
+    r = dorule(callback);
+    if (r) return r;
+  }
+
+  if (!stralloc_copys(&rules_name,ip)) return -1;
+  while (rules_name.len > 0) {
+    if (ip[rules_name.len - 1] == '.' ||
+	(ip[rules_name.len-1]==':' && rules_name.len>1)) {
+      r = dorule(callback);
+      if (r) return r;
+    }
+    --rules_name.len;
+  }
+
+  if (host) {
+    while (*host) {
+      if (*host == '.') {
+        if (!stralloc_copys(&rules_name,"=")) return -1;
+        if (!stralloc_cats(&rules_name,host)) return -1;
+	r = dorule(callback);
+	if (r) return r;
+      }
+      ++host;
+    }
+    if (!stralloc_copys(&rules_name,"=")) return -1;
+    r = dorule(callback);
+    if (r) return r;
+  }
+
+  rules_name.len = 0;
+  return dorule(callback);
+}
+
+int rules(void (*callback)(char *,unsigned int),int fd,char *ip,char *host,char *info)
+{
+  int r;
+  cdb_init(&c,fd);
+  r = doit(callback,ip,host,info);
+  cdb_free(&c);
+  return r;
+}
diff -uNr ucspi-tcp-0.88/pathexec.h ucspi-tcp-0.88-ipv6/pathexec.h
--- ucspi-tcp-0.88/pathexec.h	2000-03-18 16:18:42.000000000 +0100
+++ ucspi-tcp-0.88-ipv6/pathexec.h	2005-04-23 12:54:56.913041608 +0200
@@ -2,7 +2,7 @@
 #define PATHEXEC_H
 
 extern void pathexec_run(char *,char **,char **);
-extern int pathexec_env(char *,char *);
+extern int pathexec_env(const char *,const char *);
 extern void pathexec(char **);
 
 #endif
diff -uNr ucspi-tcp-0.88/pathexec_env.c ucspi-tcp-0.88-ipv6/pathexec_env.c
--- ucspi-tcp-0.88/pathexec_env.c	2000-03-18 16:18:42.000000000 +0100
+++ ucspi-tcp-0.88-ipv6/pathexec_env.c	2005-04-23 12:54:56.914041456 +0200
@@ -8,7 +8,7 @@
 static stralloc plus;
 static stralloc tmp;
 
-int pathexec_env(char *s,char *t)
+int pathexec_env(const char *s,const char *t)
 {
   if (!s) return 1;
   if (!stralloc_copys(&tmp,s)) return 0;
@@ -22,7 +22,6 @@
 
 void pathexec(char **argv)
 {
-  char *path;
   char **e;
   unsigned int elen;
   unsigned int i;
diff -uNr ucspi-tcp-0.88/recordio.1 ucspi-tcp-0.88-ipv6/recordio.1
--- ucspi-tcp-0.88/recordio.1	1970-01-01 01:00:00.000000000 +0100
+++ ucspi-tcp-0.88-ipv6/recordio.1	2005-04-23 12:54:56.914041456 +0200
@@ -0,0 +1,75 @@
+.TH recordio 1
+.SH NAME
+recordio \- record the input and output of a program
+.SH SYNTAX
+.B recordio
+.I program
+[
+.I arg ...
+]
+.SH DESCRIPTION
+.B recordio
+runs
+.I program
+with the given arguments.
+It prints lines to stderr
+showing the input and output of
+.IR program .
+
+At the beginning of each line on stderr,
+.B recordio
+inserts the
+.I program
+process ID,
+along with
+.B <
+for input or
+.B >
+for output.
+At the end of each line it inserts a space, a plus sign, or [EOF];
+a space indicates that there was a newline in the input or output,
+and [EOF] indicates the end of input or output.
+
+.B recordio
+prints every packet of input and output immediately.
+It does not attempt to combine packets into coherent stderr lines.
+For example,
+
+.EX
+     recordio sh -c 'cat /dev/fd/8 2>&1' > /dev/null
+.EE
+
+could produce
+
+.EX
+     5135 > cat: /dev/fd/8: Bad file descriptor 
+.br
+     5135 > [EOF]
+.EE
+
+or
+
+.EX
+     5135 > cat: +
+.br
+     5135 > /dev/fd/8+
+.br
+     5135 > : +
+.br
+     5135 > Bad file descriptor 
+.br
+     5135 > [EOF]
+.EE
+
+.B recordio
+uses several lines for long packets
+to guarantee that each line is printed atomically to stderr.
+
+.B recordio
+runs as a child of
+.IR program .
+It exits when it sees the end of
+.IR program 's
+output.
+.SH "SEE ALSO"
+tcpserver(1)
diff -uNr ucspi-tcp-0.88/remoteinfo.h ucspi-tcp-0.88-ipv6/remoteinfo.h
--- ucspi-tcp-0.88/remoteinfo.h	2000-03-18 16:18:42.000000000 +0100
+++ ucspi-tcp-0.88-ipv6/remoteinfo.h	2005-04-23 12:54:56.915041304 +0200
@@ -5,5 +5,6 @@
 #include "uint16.h"
 
 extern int remoteinfo(stralloc *,char *,uint16,char *,uint16,unsigned int);
+extern int remoteinfo6(stralloc *,char *,uint16,char *,uint16,unsigned int,uint32);
 
 #endif
diff -uNr ucspi-tcp-0.88/remoteinfo6.c ucspi-tcp-0.88-ipv6/remoteinfo6.c
--- ucspi-tcp-0.88/remoteinfo6.c	1970-01-01 01:00:00.000000000 +0100
+++ ucspi-tcp-0.88-ipv6/remoteinfo6.c	2005-04-23 12:54:56.916041152 +0200
@@ -0,0 +1,98 @@
+#include "fmt.h"
+#include "buffer.h"
+#include "socket.h"
+#include "error.h"
+#include "iopause.h"
+#include "timeoutconn.h"
+#include "remoteinfo.h"
+
+static struct taia now;
+static struct taia deadline;
+
+static int mywrite(int fd,char *buf,int len)
+{
+  iopause_fd x;
+
+  x.fd = fd;
+  x.events = IOPAUSE_WRITE;
+  for (;;) {
+    taia_now(&now);
+    iopause(&x,1,&deadline,&now);
+    if (x.revents) break;
+    if (taia_less(&deadline,&now)) {
+      errno = error_timeout;
+      return -1;
+    }
+  }
+  return write(fd,buf,len);
+}
+
+static int myread(int fd,char *buf,int len)
+{
+  iopause_fd x;
+
+  x.fd = fd;
+  x.events = IOPAUSE_READ;
+  for (;;) {
+    taia_now(&now);
+    iopause(&x,1,&deadline,&now);
+    if (x.revents) break;
+    if (taia_less(&deadline,&now)) {
+      errno = error_timeout;
+      return -1;
+    }
+  }
+  return read(fd,buf,len);
+}
+
+static int doit(stralloc *out,int s,char ipremote[16],uint16 portremote,char iplocal[16],uint16 portlocal,unsigned int timeout,uint32 netif)
+{
+  buffer b;
+  char bspace[128];
+  char strnum[FMT_ULONG];
+  int numcolons;
+  char ch;
+
+  if (socket_bind6(s,iplocal,0,netif) == -1) return -1;
+  if (timeoutconn6(s,ipremote,113,timeout,netif) == -1) return -1;
+
+  buffer_init(&b,mywrite,s,bspace,sizeof bspace);
+  buffer_put(&b,strnum,fmt_ulong(strnum,portremote));
+  buffer_put(&b," , ",3);
+  buffer_put(&b,strnum,fmt_ulong(strnum,portlocal));
+  buffer_put(&b,"\r\n",2);
+  if (buffer_flush(&b) == -1) return -1;
+
+  buffer_init(&b,myread,s,bspace,sizeof bspace);
+  numcolons = 0;
+  for (;;) {
+    if (buffer_get(&b,&ch,1) != 1) return -1;
+    if ((ch == ' ') || (ch == '\t') || (ch == '\r')) continue;
+    if (ch == '\n') return 0;
+    if (numcolons < 3) {
+      if (ch == ':') ++numcolons;
+    }
+    else {
+      if (!stralloc_append(out,&ch)) return -1;
+      if (out->len > 256) return 0;
+    }
+  }
+}
+
+int remoteinfo6(stralloc *out,char ipremote[16],uint16 portremote,char iplocal[16],uint16 portlocal,unsigned int timeout,uint32 netif)
+{
+  int s;
+  int r;
+
+  if (!stralloc_copys(out,"")) return -1;
+
+  taia_now(&now);
+  taia_uint(&deadline,timeout);
+  taia_add(&deadline,&now,&deadline);
+
+  s = socket_tcp6();
+  if (s == -1) return -1;
+  r = doit(out,s,ipremote,portremote,iplocal,portlocal,timeout,netif);
+  close(s);
+  return r;
+}
diff -uNr ucspi-tcp-0.88/rules.c ucspi-tcp-0.88-ipv6/rules.c
--- ucspi-tcp-0.88/rules.c	2000-03-18 16:18:42.000000000 +0100
+++ ucspi-tcp-0.88-ipv6/rules.c	2005-04-23 12:54:56.916041152 +0200
@@ -64,7 +64,7 @@
 
   if (!stralloc_copys(&rules_name,ip)) return -1;
   while (rules_name.len > 0) {
-    if (ip[rules_name.len - 1] == '.') {
+    if (ip[rules_name.len - 1] == '.' || ip[rules_name.len - 1] == ':') {
       r = dorule(callback);
       if (r) return r;
     }
diff -uNr ucspi-tcp-0.88/scan_ip6.c ucspi-tcp-0.88-ipv6/scan_ip6.c
--- ucspi-tcp-0.88/scan_ip6.c	1970-01-01 01:00:00.000000000 +0100
+++ ucspi-tcp-0.88-ipv6/scan_ip6.c	2005-04-23 12:54:56.917041000 +0200
@@ -0,0 +1,87 @@
+#include "scan.h"
+#include "ip4.h"
+#include "ip6.h"
+
+/*
+ * IPv6 addresses are really ugly to parse.
+ * Syntax: (h = hex digit)
+ *   1. hhhh:hhhh:hhhh:hhhh:hhhh:hhhh:hhhh:hhhh
+ *   2. any number of 0000 may be abbreviated as "::", but only once
+ *   3. The last two words may be written as IPv4 address
+ */
+
+unsigned int scan_ip6(const char *s,char ip[16])
+{
+  unsigned int i;
+  unsigned int len=0;
+  unsigned long u;
+
+  char suffix[16];
+  int prefixlen=0;
+  int suffixlen=0;
+
+  if ((i=ip4_scan((char*)s,ip+12))) {
+    for (len=0; len<12; ++len) ip[len]=V4mappedprefix[len];
+    return i;
+  }
+  for (i=0; i<16; i++) ip[i]=0;
+  for (;;) {
+    if (*s == ':') {
+      len++;
+      if (s[1] == ':') {	/* Found "::", skip to part 2 */
+	s+=2;
+	len++;
+	break;
+      }
+      s++;
+    }
+    i = scan_xlong((char*)s,&u);
+    if (!i) return 0;
+    if (prefixlen==12 && s[i]=='.') {
+      /* the last 4 bytes may be written as IPv4 address */
+      i=ip4_scan((char*)s,ip+12);
+      if (i)
+	return i+len;
+      else
+	return 0;
+    }
+    ip[prefixlen++] = (u >> 8);
+    ip[prefixlen++] = (u & 255);
+    s += i; len += i;
+    if (prefixlen==16)
+      return len;
+  }
+
+/* part 2, after "::" */
+  for (;;) {
+    if (*s == ':') {
+      if (suffixlen==0)
+	break;
+      s++;
+      len++;
+    } else if (suffixlen!=0)
+      break;
+    i = scan_xlong((char*)s,&u);
+    if (!i) {
+      len--;
+      break;
+    }
+    if (suffixlen+prefixlen<=12 && s[i]=='.') {
+      int j=ip4_scan((char*)s,suffix+suffixlen);
+      if (j) {
+	suffixlen+=4;
+	len+=j;
+	break;
+      } else
+	prefixlen=12-suffixlen;	/* make end-of-loop test true */
+    }
+    suffix[suffixlen++] = (u >> 8);
+    suffix[suffixlen++] = (u & 255);
+    s += i; len += i;
+    if (prefixlen+suffixlen==16)
+      break;
+  }
+  for (i=0; i<suffixlen; i++)
+    ip[16-suffixlen+i] = suffix[i];
+  return len;
+}
diff -uNr ucspi-tcp-0.88/scan_xlong.c ucspi-tcp-0.88-ipv6/scan_xlong.c
--- ucspi-tcp-0.88/scan_xlong.c	1970-01-01 01:00:00.000000000 +0100
+++ ucspi-tcp-0.88-ipv6/scan_xlong.c	2005-04-23 12:54:56.917041000 +0200
@@ -0,0 +1,23 @@
+#include "scan.h"
+
+static int fromhex(unsigned char c) {
+  if (c>='0' && c<='9')
+    return c-'0';
+  else if (c>='A' && c<='F')
+    return c-'A'+10;
+  else if (c>='a' && c<='f')
+    return c-'a'+10;
+  return -1;
+}
+
+unsigned int scan_xlong(char *src,unsigned long *dest) {
+  register const char *tmp=src;
+  register int l=0;
+  register unsigned char c;
+  while ((c=fromhex(*tmp))<16) {
+    l=(l<<4)+c;
+    ++tmp;
+  }
+  *dest=l;
+  return tmp-src;
+}
diff -uNr ucspi-tcp-0.88/socket.h ucspi-tcp-0.88-ipv6/socket.h
--- ucspi-tcp-0.88/socket.h	2000-03-18 16:18:42.000000000 +0100
+++ ucspi-tcp-0.88-ipv6/socket.h	2005-04-23 12:54:56.918040848 +0200
@@ -2,21 +2,52 @@
 #define SOCKET_H
 
 #include "uint16.h"
+#include "uint32.h"
 
 extern int socket_tcp(void);
 extern int socket_udp(void);
+extern int socket_tcp6(void);
+extern int socket_udp6(void);
 
-extern int socket_connect4(int,char *,uint16);
+extern int socket_connect4(int,const char *,uint16);
+extern int socket_connect6(int s,const char *ip,uint16 port,uint32 scope_id);
 extern int socket_connected(int);
-extern int socket_bind4(int,char *,uint16);
-extern int socket_bind4_reuse(int,char *,uint16);
+extern int socket_bind4(int,const char *,uint16);
+extern int socket_bind4_reuse(int,const char *,uint16);
+extern int socket_bind6(int s,const char *ip,uint16 port,uint32 scope_id);
+extern int socket_bind6_reuse(int s,const char *ip,uint16 port,uint32 scope_id);
 extern int socket_listen(int,int);
 extern int socket_accept4(int,char *,uint16 *);
+extern int socket_accept6(int s,char *ip,uint16 *port,uint32 *scope_id);
 extern int socket_recv4(int,char *,int,char *,uint16 *);
-extern int socket_send4(int,char *,int,char *,uint16);
+extern int socket_send4(int,const char *,int,const char *,uint16);
+extern int socket_recv6(int s,char *buf,unsigned int len,char *ip,uint16 *port,uint32 *scope_id);
+extern int socket_send6(int s,const char *buf,unsigned int len,const char *ip,uint16 port,uint32 scope_id);
 extern int socket_local4(int,char *,uint16 *);
 extern int socket_remote4(int,char *,uint16 *);
+extern int socket_local6(int s,char *ip,uint16 *port,uint32 *scope_id);
+extern int socket_remote6(int s,char *ip,uint16 *port,uint32 *scope_id);
+
+/* enable sending udp packets to the broadcast address */
+extern int socket_broadcast(int);
+/* join a multicast group on the given interface */
+extern int socket_mcjoin4(int,char *,char *);
+extern int socket_mcjoin6(int,char *,int);
+/* leave a multicast group on the given interface */
+extern int socket_mcleave4(int,char *);
+extern int socket_mcleave6(int,char *);
+/* set multicast TTL/hop count for outgoing packets */
+extern int socket_mcttl4(int,char);
+extern int socket_mcttl6(int,char);
+/* enable multicast loopback */
+extern int socket_mcloop4(int,char);
+extern int socket_mcloop6(int,char);
+
+extern const char* socket_getifname(uint32 interface);
+extern uint32 socket_getifidx(const char *ifname);
 
 extern void socket_tryreservein(int,int);
 
+extern int noipv6;
+
 #endif
diff -uNr ucspi-tcp-0.88/socket_accept6.c ucspi-tcp-0.88-ipv6/socket_accept6.c
--- ucspi-tcp-0.88/socket_accept6.c	1970-01-01 01:00:00.000000000 +0100
+++ ucspi-tcp-0.88-ipv6/socket_accept6.c	2005-04-23 12:54:56.919040696 +0200
@@ -0,0 +1,44 @@
+#include <sys/types.h>
+#include <sys/param.h>
+#include <sys/socket.h>
+#include <netinet/in.h>
+#include "byte.h"
+#include "socket.h"
+#include "ip6.h"
+#include "haveip6.h"
+#include "error.h"
+
+int socket_accept6(int s,char ip[16],uint16 *port,uint32 *scope_id)
+{
+#ifdef LIBC_HAS_IP6
+  struct sockaddr_in6 sa;
+#else
+  struct sockaddr_in sa;
+#endif
+  unsigned int dummy = sizeof sa;
+  int fd;
+
+  fd = accept(s,(struct sockaddr *) &sa,&dummy);
+  if (fd == -1) return -1;
+
+#ifdef LIBC_HAS_IP6
+  if (sa.sin6_family==AF_INET) {
+    struct sockaddr_in *sa4=(struct sockaddr_in*)&sa;
+    byte_copy(ip,12,V4mappedprefix);
+    byte_copy(ip+12,4,(char *) &sa4->sin_addr);
+    uint16_unpack_big((char *) &sa4->sin_port,port);
+    return fd;
+  }
+  byte_copy(ip,16,(char *) &sa.sin6_addr);
+  uint16_unpack_big((char *) &sa.sin6_port,port);
+  if (scope_id) *scope_id=sa.sin6_scope_id;
+
+  return fd;
+#else
+  byte_copy(ip,12,V4mappedprefix);
+  byte_copy(ip+12,4,(char *) &sa.sin_addr);
+  uint16_unpack_big((char *) &sa.sin_port,port);
+  if (scope_id) *scope_id=0;
+  return fd;
+#endif
+}
diff -uNr ucspi-tcp-0.88/socket_bind.c ucspi-tcp-0.88-ipv6/socket_bind.c
--- ucspi-tcp-0.88/socket_bind.c	2000-03-18 16:18:42.000000000 +0100
+++ ucspi-tcp-0.88-ipv6/socket_bind.c	2005-04-23 12:54:56.919040696 +0200
@@ -5,7 +5,7 @@
 #include "byte.h"
 #include "socket.h"
 
-int socket_bind4(int s,char ip[4],uint16 port)
+int socket_bind4(int s,const char ip[4],uint16 port)
 {
   struct sockaddr_in sa;
 
@@ -17,7 +17,7 @@
   return bind(s,(struct sockaddr *) &sa,sizeof sa);
 }
 
-int socket_bind4_reuse(int s,char ip[4],uint16 port)
+int socket_bind4_reuse(int s,const char ip[4],uint16 port)
 {
   int opt = 1;
   setsockopt(s,SOL_SOCKET,SO_REUSEADDR,&opt,sizeof opt);
diff -uNr ucspi-tcp-0.88/socket_bind6.c ucspi-tcp-0.88-ipv6/socket_bind6.c
--- ucspi-tcp-0.88/socket_bind6.c	1970-01-01 01:00:00.000000000 +0100
+++ ucspi-tcp-0.88-ipv6/socket_bind6.c	2005-04-23 12:54:56.920040544 +0200
@@ -0,0 +1,45 @@
+#include <sys/types.h>
+#include <sys/param.h>
+#include <sys/socket.h>
+#include <netinet/in.h>
+#include "byte.h"
+#include "socket.h"
+#include "ip6.h"
+#include "haveip6.h"
+#include "error.h"
+
+int socket_bind6(int s,const char ip[16],uint16 port,uint32 scope_id)
+{
+#ifdef LIBC_HAS_IP6
+  struct sockaddr_in6 sa;
+
+  if (noipv6) {
+#endif
+    int i;
+    for (i=0; i<16; i++)
+      if (ip[i]!=0) break;
+    if (i==16 || ip6_isv4mapped(ip))
+      return socket_bind4(s,ip+12,port);
+#ifdef LIBC_HAS_IP6
+  }
+  byte_zero(&sa,sizeof sa);
+  sa.sin6_family = AF_INET6;
+  uint16_pack_big((char *) &sa.sin6_port,port);
+/*  implicit: sa.sin6_flowinfo = 0; */
+  byte_copy((char *) &sa.sin6_addr,16,ip);
+  sa.sin6_scope_id=scope_id;
+
+  return bind(s,(struct sockaddr *) &sa,sizeof sa);
+#else
+  errno=error_proto;
+  return -1;
+#endif
+}
+
+int socket_bind6_reuse(int s,const char ip[16],uint16 port,uint32 scope_id)
+{
+  int opt = 1;
+  setsockopt(s,SOL_SOCKET,SO_REUSEADDR,&opt,sizeof opt);
+  return socket_bind6(s,ip,port,scope_id);
+}
+
diff -uNr ucspi-tcp-0.88/socket_conn.c ucspi-tcp-0.88-ipv6/socket_conn.c
--- ucspi-tcp-0.88/socket_conn.c	2000-03-18 16:18:42.000000000 +0100
+++ ucspi-tcp-0.88-ipv6/socket_conn.c	2005-04-23 12:54:56.921040392 +0200
@@ -6,7 +6,7 @@
 #include "byte.h"
 #include "socket.h"
 
-int socket_connect4(int s,char ip[4],uint16 port)
+int socket_connect4(int s,const char ip[4],uint16 port)
 {
   struct sockaddr_in sa;
 
diff -uNr ucspi-tcp-0.88/socket_conn6.c ucspi-tcp-0.88-ipv6/socket_conn6.c
--- ucspi-tcp-0.88/socket_conn6.c	1970-01-01 01:00:00.000000000 +0100
+++ ucspi-tcp-0.88-ipv6/socket_conn6.c	2005-04-23 12:54:56.921040392 +0200
@@ -0,0 +1,38 @@
+#include <sys/param.h>
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <netinet/in.h>
+#include <errno.h>
+#include "byte.h"
+#include "socket.h"
+#include "ip6.h"
+#include "haveip6.h"
+#include "uint32.h"
+#include "ip4.h"
+
+int socket_connect6(int s,const char ip[16],uint16 port,uint32 scope_id)
+{
+#ifdef LIBC_HAS_IP6
+  struct sockaddr_in6 sa;
+
+  if (noipv6) {
+#endif
+    if (ip6_isv4mapped(ip))
+      return socket_connect4(s,ip+12,port);
+    if (byte_equal(ip,16,V6loopback))
+      return socket_connect4(s,ip4loopback,port);
+#ifdef LIBC_HAS_IP6
+  }
+  byte_zero(&sa,sizeof sa);
+  sa.sin6_family = PF_INET6;
+  uint16_pack_big((char *) &sa.sin6_port,port);
+  sa.sin6_flowinfo = 0;
+  sa.sin6_scope_id = scope_id;
+  byte_copy((char *) &sa.sin6_addr,16,ip);
+
+  return connect(s,(struct sockaddr *) &sa,sizeof sa);
+#else
+  errno=EPROTONOSUPPORT;
+  return -1;
+#endif
+}
diff -uNr ucspi-tcp-0.88/socket_getifidx.c ucspi-tcp-0.88-ipv6/socket_getifidx.c
--- ucspi-tcp-0.88/socket_getifidx.c	1970-01-01 01:00:00.000000000 +0100
+++ ucspi-tcp-0.88-ipv6/socket_getifidx.c	2005-04-23 12:54:56.922040240 +0200
@@ -0,0 +1,8 @@
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <net/if.h>
+#include "socket.h"
+
+uint32 socket_getifidx(const char* ifname) {
+  return if_nametoindex(ifname);
+}
diff -uNr ucspi-tcp-0.88/socket_getifname.c ucspi-tcp-0.88-ipv6/socket_getifname.c
--- ucspi-tcp-0.88/socket_getifname.c	1970-01-01 01:00:00.000000000 +0100
+++ ucspi-tcp-0.88-ipv6/socket_getifname.c	2005-04-23 12:54:56.922040240 +0200
@@ -0,0 +1,14 @@
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <net/if.h>
+#include "socket.h"
+
+static char ifname[IFNAMSIZ];
+
+const char* socket_getifname(uint32 interface) {
+  char *tmp=if_indextoname(interface,ifname);
+  if (tmp)
+    return tmp;
+  else
+    return "[unknown]";
+}
diff -uNr ucspi-tcp-0.88/socket_ip4loopback.c ucspi-tcp-0.88-ipv6/socket_ip4loopback.c
--- ucspi-tcp-0.88/socket_ip4loopback.c	1970-01-01 01:00:00.000000000 +0100
+++ ucspi-tcp-0.88-ipv6/socket_ip4loopback.c	2005-04-23 12:54:56.923040088 +0200
@@ -0,0 +1,2 @@
+
+const char ip4loopback[4] = {127,0,0,1};
diff -uNr ucspi-tcp-0.88/socket_local6.c ucspi-tcp-0.88-ipv6/socket_local6.c
--- ucspi-tcp-0.88/socket_local6.c	1970-01-01 01:00:00.000000000 +0100
+++ ucspi-tcp-0.88-ipv6/socket_local6.c	2005-04-23 12:54:56.923040088 +0200
@@ -0,0 +1,39 @@
+#include <sys/types.h>
+#include <sys/param.h>
+#include <sys/socket.h>
+#include <netinet/in.h>
+#include "byte.h"
+#include "socket.h"
+#include "ip6.h"
+#include "haveip6.h"
+#include "error.h"
+
+int socket_local6(int s,char ip[16],uint16 *port,uint32 *scope_id)
+{
+#ifdef LIBC_HAS_IP6
+  struct sockaddr_in6 sa;
+#else
+  struct sockaddr_in sa;
+#endif
+  unsigned int dummy = sizeof sa;
+
+  if (getsockname(s,(struct sockaddr *) &sa,&dummy) == -1) return -1;
+#ifdef LIBC_HAS_IP6
+  if (sa.sin6_family==AF_INET) {
+    struct sockaddr_in *sa4=(struct sockaddr_in*)&sa;
+    byte_copy(ip,12,V4mappedprefix);
+    byte_copy(ip+12,4,(char *) &sa4->sin_addr);
+    uint16_unpack_big((char *) &sa4->sin_port,port);
+    return 0;
+  }
+  byte_copy(ip,16,(char *) &sa.sin6_addr);
+  uint16_unpack_big((char *) &sa.sin6_port,port);
+  if (scope_id) *scope_id=sa.sin6_scope_id;
+#else
+  byte_copy(ip,12,V4mappedprefix);
+  byte_copy(ip+12,4,(char *) &sa.sin_addr);
+  uint16_unpack_big((char *) &sa.sin_port,port);
+  if (scope_id) *scope_id=0;
+#endif
+  return 0;
+}
diff -uNr ucspi-tcp-0.88/socket_recv6.c ucspi-tcp-0.88-ipv6/socket_recv6.c
--- ucspi-tcp-0.88/socket_recv6.c	1970-01-01 01:00:00.000000000 +0100
+++ ucspi-tcp-0.88-ipv6/socket_recv6.c	2005-04-23 12:54:56.924039936 +0200
@@ -0,0 +1,44 @@
+#include <sys/types.h>
+#include <sys/param.h>
+#include <sys/socket.h>
+#include <netinet/in.h>
+#include "byte.h"
+#include "socket.h"
+#include "ip6.h"
+#include "haveip6.h"
+#include "error.h"
+
+int socket_recv6(int s,char *buf,unsigned int len,char ip[16],uint16 *port,uint32 *scope_id)
+{
+#ifdef LIBC_HAS_IP6
+  struct sockaddr_in6 sa;
+#else
+  struct sockaddr_in sa;
+#endif
+  unsigned int dummy = sizeof sa;
+  int r;
+
+  byte_zero(&sa,dummy);
+  r = recvfrom(s,buf,len,0,(struct sockaddr *) &sa,&dummy);
+  if (r == -1) return -1;
+
+#ifdef LIBC_HAS_IP6
+  if (noipv6) {
+    struct sockaddr_in *sa4=(struct sockaddr_in *)&sa;
+    byte_copy(ip,12,V4mappedprefix);
+    byte_copy(ip+12,4,(char *) &sa4->sin_addr);
+    uint16_unpack_big((char *) &sa4->sin_port,port);
+    return r;
+  }
+  byte_copy(ip,16,(char *) &sa.sin6_addr);
+  uint16_unpack_big((char *) &sa.sin6_port,port);
+  if (scope_id) *scope_id=sa.sin6_scope_id;
+#else
+  byte_copy(ip,12,(char *)V4mappedprefix);
+  byte_copy(ip+12,4,(char *) &sa.sin_addr);
+  uint16_unpack_big((char *) &sa.sin_port,port);
+  if (scope_id) *scope_id=0;
+#endif
+
+  return r;
+}
diff -uNr ucspi-tcp-0.88/socket_remote6.c ucspi-tcp-0.88-ipv6/socket_remote6.c
--- ucspi-tcp-0.88/socket_remote6.c	1970-01-01 01:00:00.000000000 +0100
+++ ucspi-tcp-0.88-ipv6/socket_remote6.c	2005-04-23 12:54:56.925039784 +0200
@@ -0,0 +1,39 @@
+#include <sys/types.h>
+#include <sys/param.h>
+#include <sys/socket.h>
+#include <netinet/in.h>
+#include "byte.h"
+#include "socket.h"
+#include "ip6.h"
+#include "haveip6.h"
+#include "error.h"
+
+int socket_remote6(int s,char ip[16],uint16 *port,uint32 *scope_id)
+{
+#ifdef LIBC_HAS_IP6
+  struct sockaddr_in6 sa;
+#else
+  struct sockaddr_in sa;
+#endif
+  unsigned int dummy = sizeof sa;
+
+  if (getpeername(s,(struct sockaddr *) &sa,&dummy) == -1) return -1;
+#ifdef LIBC_HAS_IP6
+  if (sa.sin6_family==AF_INET) {
+    struct sockaddr_in *sa4=(struct sockaddr_in*)&sa;
+    byte_copy(ip,12,V4mappedprefix);
+    byte_copy(ip+12,4,(char *) &sa4->sin_addr);
+    uint16_unpack_big((char *) &sa4->sin_port,port);
+    return 0;
+  }
+  byte_copy(ip,16,(char *) &sa.sin6_addr);
+  uint16_unpack_big((char *) &sa.sin6_port,port);
+  if (scope_id) *scope_id=sa.sin6_scope_id;
+#else
+  byte_copy(ip,12,V4mappedprefix);
+  byte_copy(ip+12,4,(char *) &sa.sin_addr);
+  uint16_unpack_big((char *) &sa.sin_port,port);
+  if (scope_id) *scope_id=0;
+#endif
+  return 0;
+}
diff -uNr ucspi-tcp-0.88/socket_send6.c ucspi-tcp-0.88-ipv6/socket_send6.c
--- ucspi-tcp-0.88/socket_send6.c	1970-01-01 01:00:00.000000000 +0100
+++ ucspi-tcp-0.88-ipv6/socket_send6.c	2005-04-23 12:54:56.925039784 +0200
@@ -0,0 +1,40 @@
+#include <sys/types.h>
+#include <sys/param.h>
+#include <sys/socket.h>
+#include <netinet/in.h>
+#include "byte.h"
+#include "socket.h"
+#include "ip4.h"
+#include "ip6.h"
+#include "haveip6.h"
+#include "error.h"
+
+int socket_send6(int s,const char *buf,unsigned int len,const char ip[16],uint16 port,uint32 scope_id)
+{
+#ifdef LIBC_HAS_IP6
+  struct sockaddr_in6 sa;
+#else
+  struct sockaddr_in sa;
+#endif
+
+  byte_zero(&sa,sizeof sa);
+#ifdef LIBC_HAS_IP6
+  if (noipv6) {
+#endif
+    if (ip6_isv4mapped(ip))
+      return socket_send4(s,buf,len,ip+12,port);
+    if (byte_equal(ip,16,V6loopback))
+      return socket_send4(s,buf,len,ip4loopback,port);
+#ifdef LIBC_HAS_IP6
+    errno=error_proto;
+    return -1;
+  }
+  sa.sin6_family = AF_INET6;
+  uint16_pack_big((char *) &sa.sin6_port,port);
+  byte_copy((char *) &sa.sin6_addr,16,ip);
+  return sendto(s,buf,len,0,(struct sockaddr *) &sa,sizeof sa);
+#else
+  errno=error_proto;
+  return -1;
+#endif
+}
diff -uNr ucspi-tcp-0.88/socket_tcp6.c ucspi-tcp-0.88-ipv6/socket_tcp6.c
--- ucspi-tcp-0.88/socket_tcp6.c	1970-01-01 01:00:00.000000000 +0100
+++ ucspi-tcp-0.88-ipv6/socket_tcp6.c	2005-04-23 12:54:56.926039632 +0200
@@ -0,0 +1,38 @@
+#include <sys/types.h>
+#include <sys/param.h>
+#include <sys/socket.h>
+#include <netinet/in.h>
+#include <errno.h>
+#include "ndelay.h"
+#include "socket.h"
+#include "haveip6.h"
+#include "error.h"
+
+#ifdef LIBC_HAS_IP6
+int noipv6=0;
+#else
+int noipv6=1;
+#endif
+
+int socket_tcp6(void)
+{
+#ifdef LIBC_HAS_IP6
+  int s;
+
+  if (noipv6) goto compat;
+  s = socket(PF_INET6,SOCK_STREAM,0);
+  if (s == -1) {
+    if (errno == EINVAL || errno == EAFNOSUPPORT) {
+compat:
+      s=socket(AF_INET,SOCK_STREAM,0);
+      noipv6=1;
+      if (s==-1) return -1;
+    } else
+    return -1;
+  }
+  if (ndelay_on(s) == -1) { close(s); return -1; }
+  return s;
+#else
+  return socket_tcp();
+#endif
+}
diff -uNr ucspi-tcp-0.88/socket_udp6.c ucspi-tcp-0.88-ipv6/socket_udp6.c
--- ucspi-tcp-0.88/socket_udp6.c	1970-01-01 01:00:00.000000000 +0100
+++ ucspi-tcp-0.88-ipv6/socket_udp6.c	2005-04-23 12:54:56.926039632 +0200
@@ -0,0 +1,32 @@
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <netinet/in.h>
+#include <errno.h>
+#include "haveip6.h"
+#include "socket.h"
+
+#ifndef EAFNOSUPPORT
+#define EAFNOSUPPORT EINVAL
+#endif
+
+int socket_udp6(void)
+{
+#ifdef LIBC_HAS_IP6
+  int s;
+
+  if (noipv6) goto compat;
+  s = socket(PF_INET6,SOCK_DGRAM,0);
+  if (s == -1) {
+    if (errno == EINVAL || errno == EAFNOSUPPORT) {
+compat:
+      s=socket(AF_INET,SOCK_DGRAM,0);
+      noipv6=1;
+      if (s==-1) return -1;
+    } else
+    return -1;
+  }
+  return s;
+#else
+  return socket_udp();
+#endif
+}
diff -uNr ucspi-tcp-0.88/socket_v4mappedprefix.c ucspi-tcp-0.88-ipv6/socket_v4mappedprefix.c
--- ucspi-tcp-0.88/socket_v4mappedprefix.c	1970-01-01 01:00:00.000000000 +0100
+++ ucspi-tcp-0.88-ipv6/socket_v4mappedprefix.c	2005-04-23 12:54:56.927039480 +0200
@@ -0,0 +1,2 @@
+
+const unsigned char V4mappedprefix[12]={0,0,0,0,0,0,0,0,0,0,0xff,0xff};
diff -uNr ucspi-tcp-0.88/socket_v6any.c ucspi-tcp-0.88-ipv6/socket_v6any.c
--- ucspi-tcp-0.88/socket_v6any.c	1970-01-01 01:00:00.000000000 +0100
+++ ucspi-tcp-0.88-ipv6/socket_v6any.c	2005-04-23 12:54:56.927039480 +0200
@@ -0,0 +1,2 @@
+
+const unsigned char V6any[16]={0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0};
diff -uNr ucspi-tcp-0.88/socket_v6loopback.c ucspi-tcp-0.88-ipv6/socket_v6loopback.c
--- ucspi-tcp-0.88/socket_v6loopback.c	1970-01-01 01:00:00.000000000 +0100
+++ ucspi-tcp-0.88-ipv6/socket_v6loopback.c	2005-04-23 12:54:56.928039328 +0200
@@ -0,0 +1,2 @@
+
+const unsigned char V6loopback[16]={0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1};
diff -uNr ucspi-tcp-0.88/str.h ucspi-tcp-0.88-ipv6/str.h
--- ucspi-tcp-0.88/str.h	2000-03-18 16:18:42.000000000 +0100
+++ ucspi-tcp-0.88-ipv6/str.h	2005-04-23 12:54:56.928039328 +0200
@@ -1,13 +1,13 @@
 #ifndef STR_H
 #define STR_H
 
-extern unsigned int str_copy(char *,char *);
-extern int str_diff(char *,char *);
-extern int str_diffn(char *,char *,unsigned int);
-extern unsigned int str_len(char *);
-extern unsigned int str_chr(char *,int);
-extern unsigned int str_rchr(char *,int);
-extern int str_start(char *,char *);
+extern unsigned int str_copy(char *,const char *);
+extern int str_diff(const char *,const char *);
+extern int str_diffn(const char *,const char *,unsigned int);
+extern unsigned int str_len(const char *);
+extern unsigned int str_chr(const char *,int);
+extern unsigned int str_rchr(const char *,int);
+extern int str_start(const char *,const char *);
 
 #define str_equal(s,t) (!str_diff((s),(t)))
 
diff -uNr ucspi-tcp-0.88/str_chr.c ucspi-tcp-0.88-ipv6/str_chr.c
--- ucspi-tcp-0.88/str_chr.c	2000-03-18 16:18:42.000000000 +0100
+++ ucspi-tcp-0.88-ipv6/str_chr.c	2005-04-23 12:54:56.928039328 +0200
@@ -1,9 +1,9 @@
 #include "str.h"
 
-unsigned int str_chr(register char *s,int c)
+unsigned int str_chr(register const char *s,int c)
 {
   register char ch;
-  register char *t;
+  register const char *t;
 
   ch = c;
   t = s;
diff -uNr ucspi-tcp-0.88/str_diff.c ucspi-tcp-0.88-ipv6/str_diff.c
--- ucspi-tcp-0.88/str_diff.c	2000-03-18 16:18:42.000000000 +0100
+++ ucspi-tcp-0.88-ipv6/str_diff.c	2005-04-23 12:54:56.929039176 +0200
@@ -1,6 +1,6 @@
 #include "str.h"
 
-int str_diff(register char *s,register char *t)
+int str_diff(register const char *s,register const char *t)
 {
   register char x;
 
diff -uNr ucspi-tcp-0.88/str_len.c ucspi-tcp-0.88-ipv6/str_len.c
--- ucspi-tcp-0.88/str_len.c	2000-03-18 16:18:42.000000000 +0100
+++ ucspi-tcp-0.88-ipv6/str_len.c	2005-04-23 12:54:56.929039176 +0200
@@ -1,8 +1,8 @@
 #include "str.h"
 
-unsigned int str_len(char *s)
+unsigned int str_len(const char *s)
 {
-  register char *t;
+  register const char *t;
 
   t = s;
   for (;;) {
diff -uNr ucspi-tcp-0.88/str_start.c ucspi-tcp-0.88-ipv6/str_start.c
--- ucspi-tcp-0.88/str_start.c	2000-03-18 16:18:42.000000000 +0100
+++ ucspi-tcp-0.88-ipv6/str_start.c	2005-04-23 12:54:56.930039024 +0200
@@ -1,6 +1,6 @@
 #include "str.h"
 
-int str_start(register char *s,register char *t)
+int str_start(register const char *s,register const char *t)
 {
   register char x;
 
diff -uNr ucspi-tcp-0.88/stralloc.h ucspi-tcp-0.88-ipv6/stralloc.h
--- ucspi-tcp-0.88/stralloc.h	2000-03-18 16:18:42.000000000 +0100
+++ ucspi-tcp-0.88-ipv6/stralloc.h	2005-04-23 12:54:56.930039024 +0200
@@ -9,18 +9,20 @@
 extern int stralloc_readyplus(stralloc *,unsigned int);
 extern int stralloc_copy(stralloc *,stralloc *);
 extern int stralloc_cat(stralloc *,stralloc *);
-extern int stralloc_copys(stralloc *,char *);
-extern int stralloc_cats(stralloc *,char *);
-extern int stralloc_copyb(stralloc *,char *,unsigned int);
-extern int stralloc_catb(stralloc *,char *,unsigned int);
+extern int stralloc_copys(stralloc *,const char *);
+extern int stralloc_cats(stralloc *,const char *);
+extern int stralloc_copyb(stralloc *,const char *,unsigned int);
+extern int stralloc_catb(stralloc *,const char *,unsigned int);
 extern int stralloc_append(stralloc *,char *); /* beware: this takes a pointer to 1 char */
-extern int stralloc_starts(stralloc *,char *);
+extern int stralloc_starts(stralloc *,const char *);
 
 #define stralloc_0(sa) stralloc_append(sa,"")
 
 extern int stralloc_catulong0(stralloc *,unsigned long,unsigned int);
 extern int stralloc_catlong0(stralloc *,long,unsigned int);
 
+extern void stralloc_free(stralloc *);
+
 #define stralloc_catlong(sa,l) (stralloc_catlong0((sa),(l),0))
 #define stralloc_catuint0(sa,i,n) (stralloc_catulong0((sa),(i),(n)))
 #define stralloc_catint0(sa,i,n) (stralloc_catlong0((sa),(i),(n)))
diff -uNr ucspi-tcp-0.88/stralloc_catb.c ucspi-tcp-0.88-ipv6/stralloc_catb.c
--- ucspi-tcp-0.88/stralloc_catb.c	2000-03-18 16:18:42.000000000 +0100
+++ ucspi-tcp-0.88-ipv6/stralloc_catb.c	2005-04-23 12:54:56.931038872 +0200
@@ -1,7 +1,7 @@
 #include "stralloc.h"
 #include "byte.h"
 
-int stralloc_catb(stralloc *sa,char *s,unsigned int n)
+int stralloc_catb(stralloc *sa,const char *s,unsigned int n)
 {
   if (!sa->s) return stralloc_copyb(sa,s,n);
   if (!stralloc_readyplus(sa,n + 1)) return 0;
diff -uNr ucspi-tcp-0.88/stralloc_cats.c ucspi-tcp-0.88-ipv6/stralloc_cats.c
--- ucspi-tcp-0.88/stralloc_cats.c	2000-03-18 16:18:42.000000000 +0100
+++ ucspi-tcp-0.88-ipv6/stralloc_cats.c	2005-04-23 12:54:56.931038872 +0200
@@ -2,7 +2,7 @@
 #include "str.h"
 #include "stralloc.h"
 
-int stralloc_cats(stralloc *sa,char *s)
+int stralloc_cats(stralloc *sa,const char *s)
 {
   return stralloc_catb(sa,s,str_len(s));
 }
diff -uNr ucspi-tcp-0.88/stralloc_opyb.c ucspi-tcp-0.88-ipv6/stralloc_opyb.c
--- ucspi-tcp-0.88/stralloc_opyb.c	2000-03-18 16:18:42.000000000 +0100
+++ ucspi-tcp-0.88-ipv6/stralloc_opyb.c	2005-04-23 12:54:56.932038720 +0200
@@ -1,7 +1,7 @@
 #include "stralloc.h"
 #include "byte.h"
 
-int stralloc_copyb(stralloc *sa,char *s,unsigned int n)
+int stralloc_copyb(stralloc *sa,const char *s,unsigned int n)
 {
   if (!stralloc_ready(sa,n + 1)) return 0;
   byte_copy(sa->s,n,s);
diff -uNr ucspi-tcp-0.88/stralloc_opys.c ucspi-tcp-0.88-ipv6/stralloc_opys.c
--- ucspi-tcp-0.88/stralloc_opys.c	2000-03-18 16:18:42.000000000 +0100
+++ ucspi-tcp-0.88-ipv6/stralloc_opys.c	2005-04-23 12:54:56.932038720 +0200
@@ -2,7 +2,7 @@
 #include "str.h"
 #include "stralloc.h"
 
-int stralloc_copys(stralloc *sa,char *s)
+int stralloc_copys(stralloc *sa,const char *s)
 {
   return stralloc_copyb(sa,s,str_len(s));
 }
diff -uNr ucspi-tcp-0.88/tcp-environ.5 ucspi-tcp-0.88-ipv6/tcp-environ.5
--- ucspi-tcp-0.88/tcp-environ.5	1970-01-01 01:00:00.000000000 +0100
+++ ucspi-tcp-0.88-ipv6/tcp-environ.5	2005-04-23 12:54:56.933038568 +0200
@@ -0,0 +1,66 @@
+.TH tcp-environ 5
+.SH NAME
+tcp-environ \- TCP-related environment variables
+.SH DESCRIPTION
+The following environment variables
+describe a TCP connection.
+They are set up by
+.BR tcp-env ,
+.BR tcpclient ,
+and
+.BR tcpserver .
+Note that
+.BR TCPLOCALHOST ,
+.BR TCPREMOTEHOST ,
+and
+.B TCPREMOTEINFO
+can contain arbitrary characters.
+.TP 5
+PROTO
+The string
+.BR TCP .
+.TP 5
+TCPLOCALHOST
+The domain name of the local host,
+with uppercase letters converted to lowercase.
+If there is no currently available domain name
+for the local IP address,
+.B TCPLOCALHOST
+is not set.
+.TP 5
+TCPLOCALIP
+The IP address of the local host, in dotted-decimal form.
+.TP 5
+TCPLOCALPORT
+The local TCP port number, in decimal.
+.TP 5
+TCPREMOTEHOST
+The domain name of the remote host,
+with uppercase letters converted to lowercase.
+If there is no currently available domain name
+for the remote IP address,
+.B TCPREMOTEHOST
+is not set.
+.TP 5
+TCPREMOTEINFO
+A connection-specific string, perhaps a username,
+supplied by the remote host
+via 931/1413/IDENT/TAP.
+If the remote host did not supply connection information,
+.B TCPREMOTEINFO
+is not set.
+.TP 5
+TCPREMOTEIP
+The IP address of the remote host.
+.TP 5
+TCPREMOTEPORT
+The remote TCP port number.
+.TP 5
+TCPINTERFACE
+The interface name ("eth0") for IPv6 connections using link-local
+addresses.
+.SH "SEE ALSO"
+tcpclient(1),
+tcpserver(1),
+tcp-env(1),
+tcp(4)
diff -uNr ucspi-tcp-0.88/tcpcat.1 ucspi-tcp-0.88-ipv6/tcpcat.1
--- ucspi-tcp-0.88/tcpcat.1	1970-01-01 01:00:00.000000000 +0100
+++ ucspi-tcp-0.88-ipv6/tcpcat.1	2005-04-23 12:54:56.933038568 +0200
@@ -0,0 +1,20 @@
+.TH tcpcat 1
+.SH NAME
+tcpcat \- print data from a TCP port
+.SH SYNTAX
+.B tcpcat
+.I host
+.I port
+.SH DESCRIPTION
+.B tcpcat
+connects to
+.I port
+on
+.I host
+and prints any data it receives.
+
+.B tcpcat
+can be used to transfer binary data.
+It does no conversions.
+.SH "SEE ALSO"
+tcpclient(1)
diff -uNr ucspi-tcp-0.88/tcpclient.1 ucspi-tcp-0.88-ipv6/tcpclient.1
--- ucspi-tcp-0.88/tcpclient.1	1970-01-01 01:00:00.000000000 +0100
+++ ucspi-tcp-0.88-ipv6/tcpclient.1	2005-04-23 12:54:56.934038416 +0200
@@ -0,0 +1,173 @@
+.TH tcpclient 1
+.SH NAME
+tcpclient \- create an outgoing TCP connection
+.SH SYNOPSIS
+.B tcpclient
+[
+.B \-46hHrRdDqQv
+]
+[
+.B \-i\fIlocalip
+]
+[
+.B \-p\fIlocalport
+]
+[
+.B \-T\fItimeoutconn
+]
+[
+.B \-l\fIlocalname
+]
+[
+.B \-t\fItimeoutinfo
+]
+[
+.B \-I\fIinterface
+]
+.I host
+.I port
+.I program
+[
+.I arg ...
+]
+.SH DESCRIPTION
+.B tcpclient
+attempts to connect to a TCP server.
+If it is successful, it runs
+.I program
+with the given arguments,
+with descriptor 6 reading from the network
+and descriptor 7 writing to the network.
+
+The server's address is given by
+.I host
+and
+.IR port .
+.I host
+may be 0, referring to the local machine,
+or a dotted-decimal IP address,
+or a host name;
+if a host has several IP addresses,
+.B tcpclient
+tries each in turn.
+.I port
+may be a numeric port number
+or a port name.
+
+.B tcpclient
+sets up several environment variables,
+as described in
+.B tcp-environ(5).
+.SH OPTIONS
+.TP
+.B \-i\fIlocalip
+Use
+.I localip
+as the IP address for the local side of the connection;
+quit if
+.I localip
+is not available.
+.TP
+.B \-p\fIlocalport
+Use
+.I localport
+as the port number for the local side of the connection;
+quit if
+.I localport
+is not available.
+.TP
+.B \-I\fIinterface
+Use
+.I interface
+as the local network interface.  This is only defined for IPv6 sockets
+and needed if you use link-local IPv6 addresses.
+.TP
+.B \-T\fItimeoutconn
+Give up on the
+connection attempt
+after
+.I timeoutconn
+seconds. Default: 60.
+This timeout applies to each IP address tried.
+.TP
+.B \-d
+(Default.)
+Delay sending data for a fraction of a second whenever the
+remote host is responding slowly,
+to make better use of the network.
+.TP
+.B \-D
+Never delay sending data;
+enable TCP_NODELAY.
+This is appropriate for interactive connections.
+.TP
+.B \-q
+Quiet.
+Do not print any messages.
+.TP
+.B \-Q
+(Default.)
+Print error messages.
+.TP
+.B \-v
+Verbose.
+Print all available messages.
+.SH "DATA-GATHERING OPTIONS"
+.TP
+.B \-h
+(Default.)
+Look up the remote host name for
+.BR TCPREMOTEHOST .
+.TP
+.B \-H
+Do not look up the remote host name;
+unset
+.BR TCPREMOTEHOST .
+.TP
+.B \-l\fIlocalname
+Do not look up the local host name;
+use
+.I localname
+for
+.BR TCPLOCALHOST .
+.TP
+.B \-r
+(Default.)
+Attempt to obtain
+.B TCPREMOTEINFO
+from the remote host.
+.TP
+.B \-R
+Do not attempt to obtain
+.B TCPREMOTEINFO
+from the remote host.
+.TP
+.B \-t\fItimeoutinfo
+Give up on the 
+.B TCPREMOTEINFO
+connection attempt
+after
+.I timeoutinfo
+seconds. Default: 26.
+.TP
+.B \-4
+Fall back to IPv4 sockets.  This is necessary for terminally broken
+systems like OpenBSD which will not let IPv6 sockets connect to
+V4-mapped IPv6 addresses.  Please note that this also applies to DNS
+lookups, so you will have to use an DNS resolver with an IPv6 address to
+connect to IPv6 systems.  Use \fBDNSCACHEIP\fR to set the DNS resolver
+IP dynamically.
+.TP
+.B \-6
+Force IPv6 mode in UCSPI environment variables, even for
+IPv4 connections.  This will set \fB$PROTO\fR to \fBTCP6\fR and put
+IPv4-mapped IPv6 addresses in \fBTCPLOCALIP\fR and \fBTCPREMOTEIP\fR.
+.SH "SEE ALSO"
+date@(1),
+finger@(1),
+http@(1),
+mconnect(1),
+tcpcat(1),
+tcpserver(1),
+who@(1),
+tcp-environ(5)
diff -uNr ucspi-tcp-0.88/tcpclient.c ucspi-tcp-0.88-ipv6/tcpclient.c
--- ucspi-tcp-0.88/tcpclient.c	2000-03-18 16:18:42.000000000 +0100
+++ ucspi-tcp-0.88-ipv6/tcpclient.c	2005-04-23 12:54:56.934038416 +0200
@@ -9,6 +9,7 @@
 #include "scan.h"
 #include "str.h"
 #include "ip4.h"
+#include "ip6.h"
 #include "uint16.h"
 #include "socket.h"
 #include "fd.h"
@@ -20,6 +21,7 @@
 #include "timeoutconn.h"
 #include "remoteinfo.h"
 #include "dns.h"
+#include "byte.h"
 
 #define FATAL "tcpclient: fatal: "
 #define CONNECT "tcpclient: unable to connect to "
@@ -31,27 +33,30 @@
 void usage(void)
 {
   strerr_die1x(100,"tcpclient: usage: tcpclient \
-[ -hHrRdDqQv ] \
+[ -46hHrRdDqQv ] \
 [ -i localip ] \
 [ -p localport ] \
 [ -T timeoutconn ] \
 [ -l localname ] \
 [ -t timeoutinfo ] \
+[ -I interface ] \
 host port program");
 }
 
+int forcev6 = 0;
 int verbosity = 1;
 int flagdelay = 1;
 int flagremoteinfo = 1;
 int flagremotehost = 1;
 unsigned long itimeout = 26;
 unsigned long ctimeout[2] = { 2, 58 };
+uint32 netif = 0;
 
-char iplocal[4] = { 0,0,0,0 };
+char iplocal[16] = { 0,0,0,0, 0,0,0,0, 0,0,0,0, 0,0,0,0 };
 uint16 portlocal = 0;
 char *forcelocal = 0;
 
-char ipremote[4];
+char ipremote[16];
 uint16 portremote;
 
 char *hostname;
@@ -61,12 +66,13 @@
 static stralloc tmp;
 static stralloc fqdn;
 char strnum[FMT_ULONG];
-char ipstr[IP4_FMT];
+char ipstr[IP6_FMT];
 
 char seed[128];
 
 main(int argc,char **argv)
 {
+  int fakev4=0;
   unsigned long u;
   int opt;
   char *x;
@@ -80,8 +86,10 @@
   close(7);
   sig_ignore(sig_pipe);
  
-  while ((opt = getopt(argc,argv,"dDvqQhHrRi:p:t:T:l:")) != opteof)
+  while ((opt = getopt(argc,argv,"46dDvqQhHrRi:p:t:T:l:I:")) != opteof)
     switch(opt) {
+      case '4': noipv6 = 1; break;
+      case '6': forcev6 = 1; break;
       case 'd': flagdelay = 1; break;
       case 'D': flagdelay = 0; break;
       case 'v': verbosity = 2; break;
@@ -97,7 +105,8 @@
 		if (optarg[j] == '+') ++j;
 		scan_ulong(optarg + j,&ctimeout[1]);
 		break;
-      case 'i': if (!ip4_scan(optarg,iplocal)) usage(); break;
+      case 'i': if (!scan_ip6(optarg,iplocal)) usage(); break;
+      case 'I': netif=socket_getifidx(optarg); break;
       case 'p': scan_ulong(optarg,&u); portlocal = u; break;
       default: usage();
     }
@@ -108,8 +117,8 @@
 
   hostname = *argv;
   if (!hostname) usage();
-  if (str_equal(hostname,"")) hostname = "127.0.0.1";
-  if (str_equal(hostname,"0")) hostname = "127.0.0.1";
+  if (!hostname[0] || str_equal(hostname,"0"))
+    hostname = (noipv6?"127.0.0.1":"::1");
 
   x = *++argv;
   if (!x) usage();
@@ -127,33 +136,36 @@
   if (!*++argv) usage();
 
   if (!stralloc_copys(&tmp,hostname)) nomem();
-  if (dns_ip4_qualify(&addresses,&fqdn,&tmp) == -1)
+  if (dns_ip6_qualify(&addresses,&fqdn,&tmp) == -1)
     strerr_die4sys(111,FATAL,"temporarily unable to figure out IP address for ",hostname,": ");
-  if (addresses.len < 4)
+  if (addresses.len < 16)
     strerr_die3x(111,FATAL,"no IP address for ",hostname);
 
-  if (addresses.len == 4) {
+  if (addresses.len == 16) {
     ctimeout[0] += ctimeout[1];
     ctimeout[1] = 0;
   }
 
   for (cloop = 0;cloop < 2;++cloop) {
     if (!stralloc_copys(&moreaddresses,"")) nomem();
-    for (j = 0;j + 4 <= addresses.len;j += 4) {
-      s = socket_tcp();
+    for (j = 0;j + 16 <= addresses.len;j += 4) {
+      s = socket_tcp6();
       if (s == -1)
         strerr_die2sys(111,FATAL,"unable to create socket: ");
-      if (socket_bind4(s,iplocal,portlocal) == -1)
+      if (socket_bind6(s,iplocal,portlocal,netif) == -1)
         strerr_die2sys(111,FATAL,"unable to bind socket: ");
-      if (timeoutconn(s,addresses.s + j,portremote,ctimeout[cloop]) == 0)
+      if (timeoutconn6(s,addresses.s + j,portremote,ctimeout[cloop],netif) == 0)
         goto CONNECTED;
       close(s);
       if (!cloop && ctimeout[1] && (errno == error_timeout)) {
-	if (!stralloc_catb(&moreaddresses,addresses.s + j,4)) nomem();
+	if (!stralloc_catb(&moreaddresses,addresses.s + j,16)) nomem();
       }
       else {
         strnum[fmt_ulong(strnum,portremote)] = 0;
-        ipstr[ip4_fmt(ipstr,addresses.s + j)] = 0;
+	if (ip6_isv4mapped(addresses.s+j))
+	  ipstr[ip4_fmt(ipstr,addresses.s + j + 12)] = 0;
+	else
+	  ipstr[ip6_fmt(ipstr,addresses.s + j)] = 0;
         strerr_warn5(CONNECT,ipstr," port ",strnum,": ",&strerr_sys);
       }
     }
@@ -169,37 +181,46 @@
   if (!flagdelay)
     socket_tcpnodelay(s); /* if it fails, bummer */
 
-  if (!pathexec_env("PROTO","TCP")) nomem();
-
-  if (socket_local4(s,iplocal,&portlocal) == -1)
+  if (socket_local6(s,iplocal,&portlocal,&netif) == -1)
     strerr_die2sys(111,FATAL,"unable to get local address: ");
 
+  if (!forcev6 && (ip6_isv4mapped(iplocal) || byte_equal(iplocal,16,V6any)))
+    fakev4=1;
+
+  if (!pathexec_env("PROTO",fakev4?"TCP":"TCP6")) nomem();
+
   strnum[fmt_ulong(strnum,portlocal)] = 0;
   if (!pathexec_env("TCPLOCALPORT",strnum)) nomem();
-  ipstr[ip4_fmt(ipstr,iplocal)] = 0;
+  if (fakev4)
+    ipstr[ip4_fmt(ipstr,iplocal+12)] = 0;
+  else
+    ipstr[ip6_fmt(ipstr,iplocal)] = 0;
   if (!pathexec_env("TCPLOCALIP",ipstr)) nomem();
 
   x = forcelocal;
   if (!x)
-    if (dns_name4(&tmp,iplocal) == 0) {
+    if (dns_name6(&tmp,iplocal) == 0) {
       if (!stralloc_0(&tmp)) nomem();
       x = tmp.s;
     }
   if (!pathexec_env("TCPLOCALHOST",x)) nomem();
 
-  if (socket_remote4(s,ipremote,&portremote) == -1)
+  if (socket_remote6(s,ipremote,&portremote,&netif) == -1)
     strerr_die2sys(111,FATAL,"unable to get remote address: ");
 
   strnum[fmt_ulong(strnum,portremote)] = 0;
   if (!pathexec_env("TCPREMOTEPORT",strnum)) nomem();
-  ipstr[ip4_fmt(ipstr,ipremote)] = 0;
+  if (fakev4)
+    ipstr[ip4_fmt(ipstr,ipremote+12)] = 0;
+  else
+    ipstr[ip6_fmt(ipstr,ipremote)] = 0;
   if (!pathexec_env("TCPREMOTEIP",ipstr)) nomem();
   if (verbosity >= 2)
     strerr_warn4("tcpclient: connected to ",ipstr," port ",strnum,0);
 
   x = 0;
   if (flagremotehost)
-    if (dns_name4(&tmp,ipremote) == 0) {
+    if (dns_name6(&tmp,ipremote) == 0) {
       if (!stralloc_0(&tmp)) nomem();
       x = tmp.s;
     }
@@ -207,7 +228,7 @@
 
   x = 0;
   if (flagremoteinfo)
-    if (remoteinfo(&tmp,ipremote,portremote,iplocal,portlocal,itimeout) == 0) {
+    if (remoteinfo6(&tmp,ipremote,portremote,iplocal,portlocal,itimeout,netif) == 0) {
       if (!stralloc_0(&tmp)) nomem();
       x = tmp.s;
     }
diff -uNr ucspi-tcp-0.88/tcprules.1 ucspi-tcp-0.88-ipv6/tcprules.1
--- ucspi-tcp-0.88/tcprules.1	1970-01-01 01:00:00.000000000 +0100
+++ ucspi-tcp-0.88-ipv6/tcprules.1	2005-04-23 12:54:56.935038264 +0200
@@ -0,0 +1,221 @@
+.TH tcprules 1
+.SH NAME
+tcprules \- compile rules for tcpserver
+.SH SYNOPSIS
+.B tcprules
+.I rules.cdb
+.I rules.tmp
+.SH OVERVIEW
+.B tcpserver
+optionally follows rules to decide whether a TCP connection is acceptable.
+For example, a rule of
+
+.EX
+   18.23.0.32:deny
+.EE
+
+prohibits connections from IP address 18.23.0.32.
+
+.B tcprules
+reads rules from its standard input
+and writes them into
+.I rules.cdb
+in a binary format suited
+for quick access by
+.BR tcpserver .
+
+.B tcprules
+can be used while
+.B tcpserver
+is running:
+it ensures that
+.I rules.cdb
+is updated atomically.
+It does this by first writing the rules to
+.I rules.tmp
+and then moving
+.I rules.tmp
+on top of
+.IR rules.cdb .
+If
+.I rules.tmp
+already exists, it is destroyed.
+The directories containing
+.I rules.cdb
+and
+.I rules.tmp
+must be writable to
+.BR tcprules ;
+they must also be on the same filesystem.
+
+If there is a problem with the input,
+.B tcprules
+complains and leaves
+.I rules.cdb
+alone.
+
+The binary
+.I rules.cdb
+format is portable across machines.
+.SH "RULE FORMAT"
+A rule takes up one line.
+A file containing rules
+may also contain comments: lines beginning with # are ignored.
+
+Each rule contains an
+.BR address ,
+a colon,
+and a list of
+.BR instructions ,
+with no extra spaces.
+When
+.B tcpserver
+receives a connection from that address,
+it follows the instructions.
+.SH "ADDRESSES"
+.B tcpserver
+starts by looking for a rule with address
+.IR TCPREMOTEINFO\fB@\fITCPREMOTEIP .
+If it doesn't find one, or if
+.I TCPREMOTEINFO
+is not set, it tries the address
+.IR TCPREMOTEIP .
+If that doesn't work, it tries shorter and shorter prefixes of
+.I TCPREMOTEIP
+ending with a dot.
+If none of them work, it tries the empty string.
+
+For example, here are some rules:
+
+.EX
+   joe@127.0.0.1:first
+.br
+   18.23.0.32:second
+.br
+   127.:third
+.br
+   :fourth
+.br
+   ::1:fifth
+.EE
+
+If
+.I TCPREMOTEIP
+is
+.BR 10.119.75.38 ,
+.B tcpserver
+will follow the
+.B fourth
+instructions.
+
+If
+.I TCPREMOTEIP
+is
+.BR ::1 ,
+.B tcpserver
+will follow the
+.B fifth
+instructions.  Note that you cannot detect IPv4 mapped addresses by
+matching "::ffff", as those addresses will be converted to IPv4 before
+looking at the rules.
+
+If
+.I TCPREMOTEIP
+is
+.BR 18.23.0.32 ,
+.B tcpserver
+will follow the
+.B second
+instructions.
+
+If
+.I TCPREMOTEINFO
+is
+.B bill
+and
+.I TCPREMOTEIP
+is
+.BR 127.0.0.1 ,
+.B tcpserver
+will follow the
+.B third
+instructions.
+
+If
+.I TCPREMOTEINFO
+is
+.B joe
+and
+.I TCPREMOTEIP
+is
+.BR 127.0.0.1 ,
+.B tcpserver
+will follow the
+.B first
+instructions.
+.SH "ADDRESS RANGES"
+.B tcprules
+treats
+.B 1.2.3.37-53:ins
+as an abbreviation
+for the rules
+.BR 1.2.3.37:ins ,
+.BR 1.2.3.38:ins ,
+and so on up through
+.BR 1.2.3.53:ins .
+Similarly,
+.BR 10.2-3.:ins
+is an abbreviation for
+.B 10.2.:ins
+and
+.BR 10.3.:ins .
+.SH "INSTRUCTIONS"
+The instructions in a rule must begin with either
+.B allow
+or
+.BR deny .
+.B deny
+tells
+.B tcpserver
+to drop the connection without running anything.
+For example, the rule
+
+.EX
+   :deny
+.EE
+
+tells
+.B tcpserver
+to drop all connections that aren't handled by more specific rules.
+
+The instructions may continue with some environment variables,
+in the format
+.IR ,VAR="VALUE" .
+.B tcpserver
+adds
+.I VAR=VALUE
+to the current environment.
+For example,
+
+.EX
+   10.0.:allow,RELAYCLIENT="@fix.me"
+.EE
+
+adds
+.B RELAYCLIENT=@fix.me
+to the environment.
+The quotes here may be replaced by any repeated character:
+
+.EX
+   10.0.:allow,RELAYCLIENT=/@fix.me/
+.EE
+
+Any number of variables may be listed:
+
+.EX
+   127.0.0.1:allow,RELAYCLIENT="",TCPLOCALHOST="movie.edu"
+.EE
+.SH "SEE ALSO"
+tcprulescheck(1),
+tcpserver(1),
+tcp-environ(5)
diff -uNr ucspi-tcp-0.88/tcprules.c ucspi-tcp-0.88-ipv6/tcprules.c
--- ucspi-tcp-0.88/tcprules.c	2000-03-18 16:18:42.000000000 +0100
+++ ucspi-tcp-0.88-ipv6/tcprules.c	2005-04-23 12:54:56.935038264 +0200
@@ -123,8 +123,15 @@
     }
     line.len = len; /* for die_bad() */
 
-    colon = byte_chr(x,len,':');
-    if (colon == len) continue;
+    colon = 0;
+    for (;;) {
+      int tmp;
+      tmp = byte_chr(x + colon,len - colon,':');
+      colon += tmp;
+      if (colon == len) continue;
+      if (byte_equal(x+colon+1,4,"deny") || byte_equal(x+colon+1,5,"allow")) break;
+      ++colon;
+    }
 
     if (!stralloc_copyb(&address,x,colon)) nomem();
     if (!stralloc_copys(&data,"")) nomem();
diff -uNr ucspi-tcp-0.88/tcprulescheck.1 ucspi-tcp-0.88-ipv6/tcprulescheck.1
--- ucspi-tcp-0.88/tcprulescheck.1	1970-01-01 01:00:00.000000000 +0100
+++ ucspi-tcp-0.88-ipv6/tcprulescheck.1	2005-04-23 12:54:56.936038112 +0200
@@ -0,0 +1,25 @@
+.TH tcprulescheck 1
+.SH NAME
+tcprulescheck \- try out rules for tcpserver
+.SH SYNTAX
+.B tcprulescheck
+.I rules.cdb
+.I tcpremoteip
+[
+.I tcpremoteinfo
+]
+.SH DESCRIPTION
+.B tcprulescheck
+says what
+.B tcpserver
+will do with a connection from
+IP address
+.IR tcpremoteip ,
+following the rules compiled into
+.I rules.cdb
+by
+.BR tcprules .
+.SH "SEE ALSO"
+tcprules(1),
+tcpserver(1),
+tcp-environ(5)
diff -uNr ucspi-tcp-0.88/tcpserver.1 ucspi-tcp-0.88-ipv6/tcpserver.1
--- ucspi-tcp-0.88/tcpserver.1	1970-01-01 01:00:00.000000000 +0100
+++ ucspi-tcp-0.88-ipv6/tcpserver.1	2005-04-23 12:54:56.936038112 +0200
@@ -0,0 +1,266 @@
+.TH tcpserver 1
+.SH NAME
+tcpserver \- accept incoming TCP connections
+.SH SYNOPSIS
+.B tcpserver
+[
+.B \-146jpPhHrRoOdDqQv
+]
+[
+.B \-c\fIlimit
+]
+[
+.B \-x\fIrules.cdb
+]
+[
+.B \-B\fIbanner
+]
+[
+.B \-g\fIgid
+]
+[
+.B \-u\fIuid
+]
+[
+.B \-b\fIbacklog
+]
+[
+.B \-l\fIlocalname
+]
+[
+.B \-t\fItimeout
+]
+[
+.B \-I\fIinterface
+]
+.I host
+.I port
+.I program
+[
+.I arg ...
+]
+.SH DESCRIPTION
+.B tcpserver
+waits for connections from TCP clients.
+For each connection, it runs
+.I program
+with the given arguments,
+with descriptor 0 reading from the network
+and descriptor 1 writing to the network.
+
+The server's address is given by
+.I host
+and
+.IR port .
+.I host
+can be 0, allowing connections from any host;
+or a particular IP address,
+allowing connections only to that address;
+or a host name, allowing connections to the first IP address
+for that host.
+.I port
+may be a numeric port number
+or a port name.
+If
+.I port
+is 0,
+.B tcpserver
+will choose a free port.
+
+.B tcpserver
+sets up several environment variables,
+as described in
+.B tcp-environ(5).
+
+.B tcpserver
+exits when it receives SIGTERM.
+.SH "OPTIONS"
+.TP
+.B \-c\fIlimit
+Do not handle more than
+.I limit
+simultaneous connections.
+If there are
+.I limit
+simultaneous copies of
+.I program
+running, defer acceptance of a new connection
+until one copy finishes.
+.I limit
+must be a positive integer.
+Default: 40.
+.TP
+.B \-x\fIrules.cdb
+Follow the rules compiled into
+.I rules.cdb
+by
+.BR tcprules .
+These rules may specify setting environment variables
+or rejecting connections from bad sources.
+
+.B tcpserver
+does not read
+.I rules.cdb
+into memory;
+you can rerun
+.B tcprules
+to change
+.BR tcpserver 's
+behavior on the fly.
+.TP
+.B \-B\fIbanner
+Write
+.I banner
+to the network immediately after each connection is made.
+.B tcpserver
+writes
+.I banner
+before looking up
+.BR TCPREMOTEHOST ,
+before looking up
+.BR TCPREMOTEINFO ,
+and before checking
+.IR rules.cdb .
+
+This feature can be used to reduce latency in protocols
+where the client waits for a greeting from the server.
+.TP
+.B \-g\fIgid
+Switch group ID to
+.I gid
+after preparing to receive connections.
+.I gid
+must be a positive integer.
+.TP
+.B \-u\fIuid
+Switch user ID to 
+.I uid
+after preparing to receive connections.
+.I uid
+must be a positive integer.
+.TP
+.B \-1
+After preparing to receive connections,
+print the local port number to standard output.
+.TP
+.B \-4
+Fall back to IPv4 sockets.  This is necessary for terminally broken
+systems like OpenBSD which will not let IPv6 sockets connect to
+V4-mapped IPv6 addresses.  Please note that this also applies to DNS
+lookups, so you will have to use an DNS resolver with an IPv6 address to
+accept IPv6 connections.  Use \fBDNSCACHEIP\fR to set the DNS resolver
+IP dynamically.
+.TP
+.B \-6
+Force IPv6 mode in UCSPI environment variables, even for
+IPv4 connections.  This will set \fB$PROTO\fR to \fBTCP6\fR and put
+IPv4-mapped IPv6 addresses in \fBTCPLOCALIP\fR and \fBTCPREMOTEIP\fR.
+.TP
+.B \-I\fIinterface
+Bind to the network interface
+.I interface
+("eth0" on Linux, for example).  This is only defined and needed for
+IPv6 link-local addresses.
+.TP
+.B \-b\fIbacklog
+Allow up to
+.I backlog
+simultaneous SYN_RECEIVEDs.
+Default: 20.
+On some systems,
+.I backlog
+is silently limited to 5.
+See
+.BR listen (2)
+for more details.
+.TP
+.B \-o
+Leave IP options alone.
+If the client is sending packets along an IP source route,
+send packets back along the same route.
+.TP
+.B \-O
+(Default.)
+Kill IP options.
+A client can still use source routing to connect and to send data,
+but packets will be sent back along the default route.
+.TP
+.B \-d
+(Default.)
+Delay sending data for a fraction of a second whenever the
+remote host is responding slowly,
+to make better use of the network.
+.TP
+.B \-D
+Never delay sending data;
+enable TCP_NODELAY.
+This is appropriate for interactive connections.
+.TP
+.B \-q
+Quiet.
+Do not print any messages.
+.TP
+.B \-Q
+(Default.)
+Print error messages.
+.TP
+.B \-v
+Verbose.
+Print all available messages.
+.SH "DATA-GATHERING OPTIONS"
+.TP
+.B \-p
+Paranoid.
+After looking up the remote host name,
+look up the IP addresses for that name,
+and make sure one of them matches
+.BR TCPREMOTEIP .
+If none of them do,
+unset
+.BR TCPREMOTEHOST .
+.TP
+.B \-P
+(Default.)
+Not paranoid.
+.TP
+.B \-h
+(Default.)
+Look up the remote host name and set
+.BR TCPREMOTEHOST .
+.TP
+.B \-H
+Do not look up the remote host name.
+.TP
+.B \-l\fIlocalname
+Do not look up the local host name;
+use
+.I localname
+for
+.BR TCPLOCALHOST .
+.TP
+.B \-r
+(Default.)
+Attempt to obtain
+.B TCPREMOTEINFO
+from the remote host.
+.TP
+.B \-R
+Do not attempt to obtain
+.B TCPREMOTEINFO
+from the remote host.
+.TP
+.B \-t\fItimeout
+Give up on the 
+.B TCPREMOTEINFO
+connection attempt
+after
+.I timeout
+seconds. Default: 26.
+.SH "SEE ALSO"
+argv0(1),
+fixcr(1),
+recordio(1),
+tcpclient(1),
+tcprules(1),
+listen(2),
+tcp-environ(5)
diff -uNr ucspi-tcp-0.88/tcpserver.c ucspi-tcp-0.88-ipv6/tcpserver.c
--- ucspi-tcp-0.88/tcpserver.c	2000-03-18 16:18:42.000000000 +0100
+++ ucspi-tcp-0.88-ipv6/tcpserver.c	2005-04-23 12:54:56.937037960 +0200
@@ -7,6 +7,7 @@
 #include "fmt.h"
 #include "scan.h"
 #include "ip4.h"
+#include "ip6.h"
 #include "fd.h"
 #include "exit.h"
 #include "env.h"
@@ -28,6 +29,7 @@
 #include "sig.h"
 #include "dns.h"
 
+int forcev6 = 0;
 int verbosity = 1;
 int flagkillopts = 1;
 int flagdelay = 1;
@@ -36,20 +38,21 @@
 int flagremotehost = 1;
 int flagparanoid = 0;
 unsigned long timeout = 26;
+uint32 netif = 0;
 
 static stralloc tcpremoteinfo;
 
 uint16 localport;
 char localportstr[FMT_ULONG];
-char localip[4];
-char localipstr[IP4_FMT];
+char localip[16];
+char localipstr[IP6_FMT];
 static stralloc localhostsa;
 char *localhost = 0;
 
 uint16 remoteport;
 char remoteportstr[FMT_ULONG];
-char remoteip[4];
-char remoteipstr[IP4_FMT];
+char remoteip[16];
+char remoteipstr[IP6_FMT];
 static stralloc remotehostsa;
 char *remotehost = 0;
 
@@ -96,12 +99,12 @@
     if (ch < 33) ch = '?';
     if (ch > 126) ch = '?';
     if (ch == '%') ch = '?'; /* logger stupidity */
-    if (ch == ':') ch = '?';
+/*    if (ch == ':') ch = '?'; */
     append(&ch);
   }
   cats("...");
 }
-void env(char *s,char *t)
+void env(const char *s,const char *t)
 {
   if (!pathexec_env(s,t)) drop_nomem();
 }
@@ -135,9 +138,16 @@
 
 void doit(int t)
 {
+  int fakev4=0;
   int j;
+  uint32 scope_id;
 
-  remoteipstr[ip4_fmt(remoteipstr,remoteip)] = 0;
+  if (!forcev6 && ip6_isv4mapped(remoteip))
+    fakev4=1;
+  if (fakev4)
+    remoteipstr[ip4_fmt(remoteipstr,remoteip+12)] = 0;
+  else
+    remoteipstr[ip6_fmt(remoteipstr,remoteip)] = 0;
 
   if (verbosity >= 2) {
     strnum[fmt_ulong(strnum,getpid())] = 0;
@@ -155,30 +165,40 @@
       strerr_die2sys(111,DROP,"unable to print banner: ");
   }
 
-  if (socket_local4(t,localip,&localport) == -1)
+  if (socket_local6(t,localip,&localport,&scope_id) == -1)
     strerr_die2sys(111,DROP,"unable to get local address: ");
 
-  localipstr[ip4_fmt(localipstr,localip)] = 0;
+  if (fakev4)
+    localipstr[ip4_fmt(localipstr,localip+12)] = 0;
+  else
+    localipstr[ip6_fmt(localipstr,localip)] = 0;
   remoteportstr[fmt_ulong(remoteportstr,remoteport)] = 0;
 
   if (!localhost)
-    if (dns_name4(&localhostsa,localip) == 0)
+    if (dns_name6(&localhostsa,localip) == 0)
       if (localhostsa.len) {
 	if (!stralloc_0(&localhostsa)) drop_nomem();
 	localhost = localhostsa.s;
       }
-  env("PROTO","TCP");
+  env("PROTO",fakev4?"TCP":"TCP6");
   env("TCPLOCALIP",localipstr);
+  localipstr[ip6_fmt(localipstr,localip)]=0;
+  env("TCP6LOCALIP",localipstr);
+
   env("TCPLOCALPORT",localportstr);
+  env("TCP6LOCALPORT",localportstr);
   env("TCPLOCALHOST",localhost);
+  env("TCP6LOCALHOST",localhost);
+  if (!fakev4 && scope_id)
+    env("TCP6INTERFACE",socket_getifname(scope_id));
 
   if (flagremotehost)
-    if (dns_name4(&remotehostsa,remoteip) == 0)
+    if (dns_name6(&remotehostsa,remoteip) == 0)
       if (remotehostsa.len) {
 	if (flagparanoid)
-	  if (dns_ip4(&tmp,&remotehostsa) == 0)
-	    for (j = 0;j + 4 <= tmp.len;j += 4)
-	      if (byte_equal(remoteip,4,tmp.s + j)) {
+	  if (dns_ip6(&tmp,&remotehostsa) == 0)
+	    for (j = 0;j + 16 <= tmp.len;j += 16)
+	      if (byte_equal(remoteip,16,tmp.s + j)) {
 		flagparanoid = 0;
 		break;
 	      }
@@ -188,15 +208,20 @@
 	}
       }
   env("TCPREMOTEIP",remoteipstr);
+  remoteipstr[ip6_fmt(remoteipstr,remoteip)]=0;
+  env("TCP6REMOTEIP",remoteipstr);
   env("TCPREMOTEPORT",remoteportstr);
+  env("TCP6REMOTEPORT",remoteportstr);
   env("TCPREMOTEHOST",remotehost);
+  env("TCP6REMOTEHOST",remotehost);
 
   if (flagremoteinfo) {
-    if (remoteinfo(&tcpremoteinfo,remoteip,remoteport,localip,localport,timeout) == -1)
+    if (remoteinfo6(&tcpremoteinfo,remoteip,remoteport,localip,localport,timeout,netif) == -1)
       flagremoteinfo = 0;
     if (!stralloc_0(&tcpremoteinfo)) drop_nomem();
   }
   env("TCPREMOTEINFO",flagremoteinfo ? tcpremoteinfo.s : 0);
+  env("TCP6REMOTEINFO",flagremoteinfo ? tcpremoteinfo.s : 0);
 
   if (fnrules) {
     int fdrules;
@@ -206,7 +231,15 @@
       if (!flagallownorules) drop_rules();
     }
     else {
-      if (rules(found,fdrules,remoteipstr,remotehost,flagremoteinfo ? tcpremoteinfo.s : 0) == -1) drop_rules();
+      int fakev4=0;
+      char* temp;
+      if (!forcev6 && ip6_isv4mapped(remoteip))
+	fakev4=1;
+      if (fakev4)
+	temp=remoteipstr+7;
+      else
+	temp=remoteipstr;
+      if (rules(found,fdrules,temp,remotehost,flagremoteinfo ? tcpremoteinfo.s : 0) == -1) drop_rules();
       close(fdrules);
     }
   }
@@ -240,7 +273,7 @@
 {
   strerr_warn1("\
 tcpserver: usage: tcpserver \
-[ -1UXpPhHrRoOdDqQv ] \
+[ -461UXpPhHrRoOdDqQv ] \
 [ -c limit ] \
 [ -x rules.cdb ] \
 [ -B banner ] \
@@ -249,6 +282,7 @@
 [ -b backlog ] \
 [ -l localname ] \
 [ -t timeout ] \
+[ -I interface ] \
 host port program",0);
   _exit(100);
 }
@@ -299,8 +333,8 @@
   unsigned long u;
   int s;
   int t;
- 
-  while ((opt = getopt(argc,argv,"dDvqQhHrR1UXx:t:u:g:l:b:B:c:pPoO")) != opteof)
+
+  while ((opt = getopt(argc,argv,"46dDvqQhHrR1UXx:t:u:g:l:b:B:c:I:pPoO")) != opteof)
     switch(opt) {
       case 'b': scan_ulong(optarg,&backlog); break;
       case 'c': scan_ulong(optarg,&limit); break;
@@ -325,7 +359,10 @@
 		x = env_get("GID"); if (x) scan_ulong(x,&gid); break;
       case 'u': scan_ulong(optarg,&uid); break;
       case 'g': scan_ulong(optarg,&gid); break;
+      case 'I': netif=socket_getifidx(optarg); break;
       case '1': flag1 = 1; break;
+      case '4': noipv6 = 1; break;
+      case '6': forcev6 = 1; break;
       case 'l': localhost = optarg; break;
       default: usage();
     }
@@ -337,8 +374,7 @@
  
   hostname = *argv++;
   if (!hostname) usage();
-  if (str_equal(hostname,"")) hostname = "0.0.0.0";
-  if (str_equal(hostname,"0")) hostname = "0.0.0.0";
+  if (str_equal(hostname,"")) hostname = "0";
 
   x = *argv++;
   if (!x) usage();
@@ -348,7 +384,7 @@
     se = getservbyname(x,"tcp");
     if (!se)
       strerr_die3x(111,FATAL,"unable to figure out port number for ",x);
-    localport = ntohs(se->s_port);
+    uint16_unpack_big((char*)&se->s_port,&localport);
   }
 
   if (!*argv) usage();
@@ -358,20 +394,26 @@
   sig_catch(sig_term,sigterm);
   sig_ignore(sig_pipe);
  
-  if (!stralloc_copys(&tmp,hostname))
-    strerr_die2x(111,FATAL,"out of memory");
-  if (dns_ip4_qualify(&addresses,&fqdn,&tmp) == -1)
-    strerr_die4sys(111,FATAL,"temporarily unable to figure out IP address for ",hostname,": ");
-  if (addresses.len < 4)
-    strerr_die3x(111,FATAL,"no IP address for ",hostname);
-  byte_copy(localip,4,addresses.s);
+  if (str_equal(hostname,"0")) {
+    byte_zero(localip,sizeof localip);
+  } else {
+    if (!stralloc_copys(&tmp,hostname))
+      strerr_die2x(111,FATAL,"out of memory");
+    if (dns_ip6_qualify(&addresses,&fqdn,&tmp) == -1)
+      strerr_die4sys(111,FATAL,"temporarily unable to figure out IP address for ",hostname,": ");
+    if (addresses.len < 16)
+      strerr_die3x(111,FATAL,"no IP address for ",hostname);
+    byte_copy(localip,16,addresses.s);
+    if (ip6_isv4mapped(localip))
+      noipv6=1;
+  }
 
-  s = socket_tcp();
+  s = socket_tcp6();
   if (s == -1)
     strerr_die2sys(111,FATAL,"unable to create socket: ");
-  if (socket_bind4_reuse(s,localip,localport) == -1)
+  if (socket_bind6_reuse(s,localip,localport,netif) == -1)
     strerr_die2sys(111,FATAL,"unable to bind: ");
-  if (socket_local4(s,localip,&localport) == -1)
+  if (socket_local6(s,localip,&localport,&netif) == -1)
     strerr_die2sys(111,FATAL,"unable to get local address: ");
   if (socket_listen(s,backlog) == -1)
     strerr_die2sys(111,FATAL,"unable to listen: ");
@@ -399,7 +441,7 @@
     while (numchildren >= limit) sig_pause();
 
     sig_unblock(sig_child);
-    t = socket_accept4(s,remoteip,&remoteport);
+    t = socket_accept6(s,remoteip,&remoteport,&netif);
     sig_block(sig_child);
 
     if (t == -1) continue;
diff -uNr ucspi-tcp-0.88/timeoutconn.h ucspi-tcp-0.88-ipv6/timeoutconn.h
--- ucspi-tcp-0.88/timeoutconn.h	2000-03-18 16:18:42.000000000 +0100
+++ ucspi-tcp-0.88-ipv6/timeoutconn.h	2005-04-23 12:54:56.938037808 +0200
@@ -2,7 +2,9 @@
 #define TIMEOUTCONN_H
 
 #include "uint16.h"
+#include "uint32.h"
 
 extern int timeoutconn(int,char *,uint16,unsigned int);
+extern int timeoutconn6(int,char *,uint16,unsigned int,uint32);
 
 #endif
diff -uNr ucspi-tcp-0.88/timeoutconn6.c ucspi-tcp-0.88-ipv6/timeoutconn6.c
--- ucspi-tcp-0.88/timeoutconn6.c	1970-01-01 01:00:00.000000000 +0100
+++ ucspi-tcp-0.88-ipv6/timeoutconn6.c	2005-04-23 12:54:56.938037808 +0200
@@ -0,0 +1,34 @@
+#include "ndelay.h"
+#include "socket.h"
+#include "iopause.h"
+#include "error.h"
+#include "timeoutconn.h"
+
+int timeoutconn6(int s,char ip[16],uint16 port,unsigned int timeout,uint32 netif)
+{
+  struct taia now;
+  struct taia deadline;
+  iopause_fd x;
+
+  if (socket_connect6(s,ip,port,netif) == -1) {
+    if ((errno != error_wouldblock) && (errno != error_inprogress)) return -1;
+    x.fd = s;
+    x.events = IOPAUSE_WRITE;
+    taia_now(&now);
+    taia_uint(&deadline,timeout);
+    taia_add(&deadline,&now,&deadline);
+    for (;;) {
+      taia_now(&now);
+      iopause(&x,1,&deadline,&now);
+      if (x.revents) break;
+      if (taia_less(&deadline,&now)) {
+	errno = error_timeout; /* note that connect attempt is continuing */
+	return -1;
+      }
+    }
+    if (!socket_connected(s)) return -1;
+  }
+
+  if (ndelay_off(s) == -1) return -1;
+  return 0;
+}
diff -uNr ucspi-tcp-0.88/tryip6.c ucspi-tcp-0.88-ipv6/tryip6.c
--- ucspi-tcp-0.88/tryip6.c	1970-01-01 01:00:00.000000000 +0100
+++ ucspi-tcp-0.88-ipv6/tryip6.c	2005-04-23 12:54:56.939037656 +0200
@@ -0,0 +1,8 @@
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <netinet/in.h>
+
+main() {
+  struct sockaddr_in6 sa;
+  sa.sin6_family = PF_INET6;
+}
Files ucspi-tcp-0.88/usr/local/bin/tcpclient and ucspi-tcp-0.88-ipv6/usr/local/bin/tcpclient differ
Files ucspi-tcp-0.88/usr/local/bin/tcpserver and ucspi-tcp-0.88-ipv6/usr/local/bin/tcpserver differ
diff -uNr ucspi-tcp-0.88/usr/local/man/man1/tcpclient.1 ucspi-tcp-0.88-ipv6/usr/local/man/man1/tcpclient.1
--- ucspi-tcp-0.88/usr/local/man/man1/tcpclient.1	1970-01-01 01:00:00.000000000 +0100
+++ ucspi-tcp-0.88-ipv6/usr/local/man/man1/tcpclient.1	2005-04-23 16:57:56.441644464 +0200
@@ -0,0 +1,173 @@
+.TH tcpclient 1
+.SH NAME
+tcpclient \- create an outgoing TCP connection
+.SH SYNOPSIS
+.B tcpclient
+[
+.B \-46hHrRdDqQv
+]
+[
+.B \-i\fIlocalip
+]
+[
+.B \-p\fIlocalport
+]
+[
+.B \-T\fItimeoutconn
+]
+[
+.B \-l\fIlocalname
+]
+[
+.B \-t\fItimeoutinfo
+]
+[
+.B \-I\fIinterface
+]
+.I host
+.I port
+.I program
+[
+.I arg ...
+]
+.SH DESCRIPTION
+.B tcpclient
+attempts to connect to a TCP server.
+If it is successful, it runs
+.I program
+with the given arguments,
+with descriptor 6 reading from the network
+and descriptor 7 writing to the network.
+
+The server's address is given by
+.I host
+and
+.IR port .
+.I host
+may be 0, referring to the local machine,
+or a dotted-decimal IP address,
+or a host name;
+if a host has several IP addresses,
+.B tcpclient
+tries each in turn.
+.I port
+may be a numeric port number
+or a port name.
+
+.B tcpclient
+sets up several environment variables,
+as described in
+.B tcp-environ(5).
+.SH OPTIONS
+.TP
+.B \-i\fIlocalip
+Use
+.I localip
+as the IP address for the local side of the connection;
+quit if
+.I localip
+is not available.
+.TP
+.B \-p\fIlocalport
+Use
+.I localport
+as the port number for the local side of the connection;
+quit if
+.I localport
+is not available.
+.TP
+.B \-I\fIinterface
+Use
+.I interface
+as the local network interface.  This is only defined for IPv6 sockets
+and needed if you use link-local IPv6 addresses.
+.TP
+.B \-T\fItimeoutconn
+Give up on the
+connection attempt
+after
+.I timeoutconn
+seconds. Default: 60.
+This timeout applies to each IP address tried.
+.TP
+.B \-d
+(Default.)
+Delay sending data for a fraction of a second whenever the
+remote host is responding slowly,
+to make better use of the network.
+.TP
+.B \-D
+Never delay sending data;
+enable TCP_NODELAY.
+This is appropriate for interactive connections.
+.TP
+.B \-q
+Quiet.
+Do not print any messages.
+.TP
+.B \-Q
+(Default.)
+Print error messages.
+.TP
+.B \-v
+Verbose.
+Print all available messages.
+.SH "DATA-GATHERING OPTIONS"
+.TP
+.B \-h
+(Default.)
+Look up the remote host name for
+.BR TCPREMOTEHOST .
+.TP
+.B \-H
+Do not look up the remote host name;
+unset
+.BR TCPREMOTEHOST .
+.TP
+.B \-l\fIlocalname
+Do not look up the local host name;
+use
+.I localname
+for
+.BR TCPLOCALHOST .
+.TP
+.B \-r
+(Default.)
+Attempt to obtain
+.B TCPREMOTEINFO
+from the remote host.
+.TP
+.B \-R
+Do not attempt to obtain
+.B TCPREMOTEINFO
+from the remote host.
+.TP
+.B \-t\fItimeoutinfo
+Give up on the 
+.B TCPREMOTEINFO
+connection attempt
+after
+.I timeoutinfo
+seconds. Default: 26.
+.TP
+.B \-4
+Fall back to IPv4 sockets.  This is necessary for terminally broken
+systems like OpenBSD which will not let IPv6 sockets connect to
+V4-mapped IPv6 addresses.  Please note that this also applies to DNS
+lookups, so you will have to use an DNS resolver with an IPv6 address to
+connect to IPv6 systems.  Use \fBDNSCACHEIP\fR to set the DNS resolver
+IP dynamically.
+.TP
+.B \-6
+Force IPv6 mode in UCSPI environment variables, even for
+IPv4 connections.  This will set \fB$PROTO\fR to \fBTCP6\fR and put
+IPv4-mapped IPv6 addresses in \fBTCPLOCALIP\fR and \fBTCPREMOTEIP\fR.
+.SH "SEE ALSO"
+date@(1),
+finger@(1),
+http@(1),
+mconnect(1),
+tcpcat(1),
+tcpserver(1),
+who@(1),
+tcp-environ(5)
diff -uNr ucspi-tcp-0.88/usr/local/man/man1/tcpserver.1 ucspi-tcp-0.88-ipv6/usr/local/man/man1/tcpserver.1
--- ucspi-tcp-0.88/usr/local/man/man1/tcpserver.1	1970-01-01 01:00:00.000000000 +0100
+++ ucspi-tcp-0.88-ipv6/usr/local/man/man1/tcpserver.1	2005-04-23 16:57:56.441644464 +0200
@@ -0,0 +1,266 @@
+.TH tcpserver 1
+.SH NAME
+tcpserver \- accept incoming TCP connections
+.SH SYNOPSIS
+.B tcpserver
+[
+.B \-146jpPhHrRoOdDqQv
+]
+[
+.B \-c\fIlimit
+]
+[
+.B \-x\fIrules.cdb
+]
+[
+.B \-B\fIbanner
+]
+[
+.B \-g\fIgid
+]
+[
+.B \-u\fIuid
+]
+[
+.B \-b\fIbacklog
+]
+[
+.B \-l\fIlocalname
+]
+[
+.B \-t\fItimeout
+]
+[
+.B \-I\fIinterface
+]
+.I host
+.I port
+.I program
+[
+.I arg ...
+]
+.SH DESCRIPTION
+.B tcpserver
+waits for connections from TCP clients.
+For each connection, it runs
+.I program
+with the given arguments,
+with descriptor 0 reading from the network
+and descriptor 1 writing to the network.
+
+The server's address is given by
+.I host
+and
+.IR port .
+.I host
+can be 0, allowing connections from any host;
+or a particular IP address,
+allowing connections only to that address;
+or a host name, allowing connections to the first IP address
+for that host.
+.I port
+may be a numeric port number
+or a port name.
+If
+.I port
+is 0,
+.B tcpserver
+will choose a free port.
+
+.B tcpserver
+sets up several environment variables,
+as described in
+.B tcp-environ(5).
+
+.B tcpserver
+exits when it receives SIGTERM.
+.SH "OPTIONS"
+.TP
+.B \-c\fIlimit
+Do not handle more than
+.I limit
+simultaneous connections.
+If there are
+.I limit
+simultaneous copies of
+.I program
+running, defer acceptance of a new connection
+until one copy finishes.
+.I limit
+must be a positive integer.
+Default: 40.
+.TP
+.B \-x\fIrules.cdb
+Follow the rules compiled into
+.I rules.cdb
+by
+.BR tcprules .
+These rules may specify setting environment variables
+or rejecting connections from bad sources.
+
+.B tcpserver
+does not read
+.I rules.cdb
+into memory;
+you can rerun
+.B tcprules
+to change
+.BR tcpserver 's
+behavior on the fly.
+.TP
+.B \-B\fIbanner
+Write
+.I banner
+to the network immediately after each connection is made.
+.B tcpserver
+writes
+.I banner
+before looking up
+.BR TCPREMOTEHOST ,
+before looking up
+.BR TCPREMOTEINFO ,
+and before checking
+.IR rules.cdb .
+
+This feature can be used to reduce latency in protocols
+where the client waits for a greeting from the server.
+.TP
+.B \-g\fIgid
+Switch group ID to
+.I gid
+after preparing to receive connections.
+.I gid
+must be a positive integer.
+.TP
+.B \-u\fIuid
+Switch user ID to 
+.I uid
+after preparing to receive connections.
+.I uid
+must be a positive integer.
+.TP
+.B \-1
+After preparing to receive connections,
+print the local port number to standard output.
+.TP
+.B \-4
+Fall back to IPv4 sockets.  This is necessary for terminally broken
+systems like OpenBSD which will not let IPv6 sockets connect to
+V4-mapped IPv6 addresses.  Please note that this also applies to DNS
+lookups, so you will have to use an DNS resolver with an IPv6 address to
+accept IPv6 connections.  Use \fBDNSCACHEIP\fR to set the DNS resolver
+IP dynamically.
+.TP
+.B \-6
+Force IPv6 mode in UCSPI environment variables, even for
+IPv4 connections.  This will set \fB$PROTO\fR to \fBTCP6\fR and put
+IPv4-mapped IPv6 addresses in \fBTCPLOCALIP\fR and \fBTCPREMOTEIP\fR.
+.TP
+.B \-I\fIinterface
+Bind to the network interface
+.I interface
+("eth0" on Linux, for example).  This is only defined and needed for
+IPv6 link-local addresses.
+.TP
+.B \-b\fIbacklog
+Allow up to
+.I backlog
+simultaneous SYN_RECEIVEDs.
+Default: 20.
+On some systems,
+.I backlog
+is silently limited to 5.
+See
+.BR listen (2)
+for more details.
+.TP
+.B \-o
+Leave IP options alone.
+If the client is sending packets along an IP source route,
+send packets back along the same route.
+.TP
+.B \-O
+(Default.)
+Kill IP options.
+A client can still use source routing to connect and to send data,
+but packets will be sent back along the default route.
+.TP
+.B \-d
+(Default.)
+Delay sending data for a fraction of a second whenever the
+remote host is responding slowly,
+to make better use of the network.
+.TP
+.B \-D
+Never delay sending data;
+enable TCP_NODELAY.
+This is appropriate for interactive connections.
+.TP
+.B \-q
+Quiet.
+Do not print any messages.
+.TP
+.B \-Q
+(Default.)
+Print error messages.
+.TP
+.B \-v
+Verbose.
+Print all available messages.
+.SH "DATA-GATHERING OPTIONS"
+.TP
+.B \-p
+Paranoid.
+After looking up the remote host name,
+look up the IP addresses for that name,
+and make sure one of them matches
+.BR TCPREMOTEIP .
+If none of them do,
+unset
+.BR TCPREMOTEHOST .
+.TP
+.B \-P
+(Default.)
+Not paranoid.
+.TP
+.B \-h
+(Default.)
+Look up the remote host name and set
+.BR TCPREMOTEHOST .
+.TP
+.B \-H
+Do not look up the remote host name.
+.TP
+.B \-l\fIlocalname
+Do not look up the local host name;
+use
+.I localname
+for
+.BR TCPLOCALHOST .
+.TP
+.B \-r
+(Default.)
+Attempt to obtain
+.B TCPREMOTEINFO
+from the remote host.
+.TP
+.B \-R
+Do not attempt to obtain
+.B TCPREMOTEINFO
+from the remote host.
+.TP
+.B