Remove libalias entirely.

13 files changed, 2 insertions, 5294 deletions

diff --git a/usr.sbin/ppp/Makefile b/usr.sbin/ppp/Makefile
index 23a7673fc90..ec68cff4fac 100644
--- a/usr.sbin/ppp/Makefile
+++ b/usr.sbin/ppp/Makefile
@@ -1,4 +1,4 @@
-#	$Id: Makefile,v 1.6 1998/04/26 16:16:59 brian Exp $
+#	$Id: Makefile,v 1.7 1998/04/26 16:20:06 brian Exp $
 
 PROG=	ppp
 SRCS=	arp.c async.c auth.c ccp.c chap.c chap_ms.c chat.c \
@@ -6,7 +6,7 @@ SRCS=	arp.c async.c auth.c ccp.c chap.c chap_ms.c chat.c \
 	iplist.c lcp.c log.c lqr.c main.c mbuf.c modem.c os.c \
 	pap.c phase.c pred.c route.c server.c sig.c slcompress.c systems.c \
 	throughput.c timer.c tun.c vars.c vjcomp.c
-CFLAGS+=-Wall -Wmissing-prototypes -DHAVE_DES
+CFLAGS+=-Wall -Wmissing-prototypes -DHAVE_DES -DNOALIAS
 LDADD+= -lutil -ldes -lz
 DPADD+= ${LIBUTIL} ${LIBDES} ${LIBZ}
 MAN=	ppp.8
@@ -14,11 +14,4 @@ BINMODE=4550
 BINOWN=	root
 BINGRP=	network
 
-.if !defined(LIBALIAS)
-CFLAGS+=-DNOALIAS
-.else
-CFLAGS+=-I${.CURDIR}/libalias
-SRCS+=	alias_cmd.c loadalias.c
-.endif
-
 .include <bsd.prog.mk>
diff --git a/usr.sbin/ppp/libalias/HISTORY b/usr.sbin/ppp/libalias/HISTORY
deleted file mode 100644
index 5d29e342802..00000000000
--- a/usr.sbin/ppp/libalias/HISTORY
+++ /dev/null
@@ -1,126 +0,0 @@
-Version 1.0: August 11, 1996 (cjm)
-
-Version 1.1:  August 20, 1996  (cjm)
-    - Host accepts incoming connections for ports 0 to 1023.
-
-Version 1.2:  September 7, 1996 (cjm)
-    - Fragment handling error in alias_db.c corrected.
-
-Version 1.3:  September 15, 1996 (cjm)
-    - Generalized mechanism for handling incoming
-      connections (no more 0 to 1023 restriction).
-
-    - Increased ICMP support (will handle traceroute now).
-
-    - Improved TCP close connection logic.
-
-Version 1.4: September 16, 1996 (cjm)
-
-Version 1.5: September 17, 1996 (cjm)
-    - Corrected error in handling incoming UDP packets
-      with zero checksum.
-
-Version 1.6: September 18, 1996
-    - Simplified ICMP data storage.  Will now handle
-      tracert from Win95 and NT as well as FreeBSD
-      traceroute, which uses UDP packets to non-existent
-      ports.
-
-Verstion 1.7: January 9, 1997 (cjm)
-    - Reduced malloc() activity for ICMP echo and
-      timestamp requests.
-
-    - Added handling for out-of-order IP fragments.
-
-    - Switched to differential checksum computation
-      for IP headers (TCP, UDP and ICMP checksums
-      were already differential).
-
-    - Accepts FTP data connections from other than
-      port 20.  This allows one ftp connections
-      from two hosts which are both running packet
-      aliasing.
-
-    - Checksum error on FTP transfers.  Problem
-      in code located by Martin Renters and
-      Brian Somers.
-
-Version 1.8: January 14, 1997 (cjm)
-    - Fixed data type error in function StartPoint()
-      in alias_db.c (this bug did not exist before v1.7)
-      Problem in code located by Ari Suutari.
-
-Version 1.9: February 1, 1997 (Eivind Eklund <perhaps@yes.no>)
-    - Added support for IRC DCC (ee)
-
-    - Changed the aliasing routines to use ANSI style
-      throughout (ee)
-
-    - Minor API changes for integration with other
-      programs than PPP (ee)
-
-    - Fixed minor security hole in alias_ftp.c for
-      other applications of the aliasing software.
-      Hole could _not_ manifest in ppp+pktAlias, but
-      could potentially manifest in other applications
-      of the aliasing. (ee)
-
-    - Connections initiated from packet aliasing
-      host machine will not have their port number
-      aliased unless it conflicts with an aliasing
-      port already being used. (There is an option
-      to disable this for debugging) (cjm)
-
-    - Sockets will be allocated in cases where
-      there might be port interference with the
-      host machine.  This can be disabled in cases
-      where the ppp host will be acting purely as a
-      masquerading router and not generate any
-      traffic of its own.
-      (cjm)
-
-Version 2.0: March, 1997 (cjm)
-    - Aliasing links are cleared only when a host interface address
-      changes.
-
-    - PacketAliasPermanentLink() API added.
-
-    - Option for only aliasing private, unregistered
-      IP addresses added.
-
-    - Substantial rework to the aliasing lookup engine.
-
-Version 2.1: May, 1997 (cjm)
-    - Continuing rework to the aliasing lookup engine
-      to support multiple incoming addresses and static
-      NAT.  PacketAliasRedirectPort() and
-      PacketAliasRedirectAddr() added to API.
-
-    - Now supports outgoing as well as incoming ICMP
-      error messges.
-
-Version 2.2: July, 1997 (cjm)
-    - Rationalized API function names to all begin with
-      "PacketAlias..."  Old function names are retained
-      for backwards compatitibility.
-
-    - Packet aliasing engine will now free memory of
-      fragments which are never resolved after a timeout
-      period.  Once a fragment is resolved, it becomes
-      the users responsibility to free the memory.
-
-Version 2.3: August 11, 1997 (cjm)
-    - Problem associated with socket file descriptor
-      accumulation in alias_db.c corrected.  The sockets
-      had to be closed when a binding failed.  Problem 
-      in code located by Gordon Burditt.
-
-Version 2.4: September 1, 1997 (cjm)
-    - PKT_ALIAS_UNREGISTERED_ONLY option repaired.
-      This part of the code was incorrectly re-implemented
-      in version 2.1.
-
-Version 2.5: December, 1997 (ee)
-    - Added PKT_ALIAS_PUNCH_FW mode for firewall
-      bypass of FTP/IRC DCC data connections.  Also added
-      improved TCP connection monitoring.
diff --git a/usr.sbin/ppp/libalias/Makefile b/usr.sbin/ppp/libalias/Makefile
deleted file mode 100644
index bede41780b9..00000000000
--- a/usr.sbin/ppp/libalias/Makefile
+++ /dev/null
@@ -1,11 +0,0 @@
-LIB=	alias
-CFLAGS+=-Wall -I${.CURDIR} -DNO_FW_PUNCH
-SRCS=	alias.c alias_db.c alias_ftp.c alias_irc.c alias_util.c alias_old.c
-MAN=libalias.3 
-BINDIR=/usr/lib
-
-beforeinstall:
-	${INSTALL} -C -o ${BINOWN} -g ${BINGRP} -m 444 ${.CURDIR}/alias.h \
-		${DESTDIR}/usr/include
-
-.include <bsd.lib.mk>
diff --git a/usr.sbin/ppp/libalias/alias.c b/usr.sbin/ppp/libalias/alias.c
deleted file mode 100644
index 8ae038b3549..00000000000
--- a/usr.sbin/ppp/libalias/alias.c
+++ /dev/null
@@ -1,1114 +0,0 @@
-/* -*- mode: c; tab-width: 8; c-basic-indent: 4; -*- */
-/*
-    Alias.c provides supervisory control for the functions of the
-    packet aliasing software.  It consists of routines to monitor
-    TCP connection state, protocol-specific aliasing routines,
-    fragment handling and the following outside world functional
-    interfaces: SaveFragmentPtr, GetFragmentPtr, FragmentAliasIn,
-    PacketAliasIn and PacketAliasOut.
-
-    The other C program files are briefly described. The data
-    structure framework which holds information needed to translate
-    packets is encapsulated in alias_db.c.  Data is accessed by
-    function calls, so other segments of the program need not know
-    about the underlying data structures.  Alias_ftp.c contains
-    special code for modifying the ftp PORT command used to establish
-    data connections, while alias_irc.c do the same for IRC
-    DCC. Alias_util.c contains a few utility routines.
-
-    This software is placed into the public domain with no restrictions
-    on its distribution.
-
-    Version 1.0 August, 1996  (cjm)
-
-    Version 1.1 August 20, 1996  (cjm)
-        PPP host accepts incoming connections for ports 0 to 1023.
-        (Gary Roberts pointed out the need to handle incoming
-         connections.)
-
-    Version 1.2 September 7, 1996 (cjm)
-        Fragment handling error in alias_db.c corrected.
-        (Tom Torrance helped fix this problem.)
-
-    Version 1.4 September 16, 1996 (cjm)
-        - A more generalized method for handling incoming
-          connections, without the 0-1023 restriction, is
-          implemented in alias_db.c
-        - Improved ICMP support in alias.c.  Traceroute
-          packet streams can now be correctly aliased.
-        - TCP connection closing logic simplified in
-          alias.c and now allows for additional 1 minute
-          "grace period" after FIN or RST is observed.
-
-    Version 1.5 September 17, 1996 (cjm)
-        Corrected error in handling incoming UDP packets with 0 checksum.
-        (Tom Torrance helped fix this problem.)
-
-    Version 1.6 September 18, 1996 (cjm)
-        Simplified ICMP aliasing scheme.  Should now support
-        traceroute from Win95 as well as FreeBSD.
-
-    Version 1.7 January 9, 1997 (cjm)
-        - Out-of-order fragment handling.
-        - IP checksum error fixed for ftp transfers
-          from aliasing host.
-        - Integer return codes added to all
-          aliasing/de-aliasing functions.
-        - Some obsolete comments cleaned up.
-        - Differential checksum computations for
-          IP header (TCP, UDP and ICMP were already
-          differential).
-
-    Version 2.1 May 1997 (cjm)
-        - Added support for outgoing ICMP error
-          messages.
-        - Added two functions PacketAliasIn2()
-          and PacketAliasOut2() for dynamic address
-          control (e.g. round-robin allocation of
-          incoming packets).
-
-    Version 2.2 July 1997 (cjm)
-        - Rationalized API function names to begin
-          with "PacketAlias..."
-        - Eliminated PacketAliasIn2() and
-          PacketAliasOut2() as poorly conceived.
-
-    See HISTORY file for additional revisions.
-
-*/
-
-#include <stdio.h>
-#include <unistd.h>
-
-#include <sys/param.h>
-#include <sys/types.h>
-
-#include <netinet/in_systm.h>
-#include <netinet/in.h>
-#include <netinet/ip.h>
-#include <netinet/ip_icmp.h>
-#include <netinet/tcp.h>
-#include <netinet/udp.h>
-
-#include "alias_local.h"
-#include "alias.h"
-
-#define FTP_CONTROL_PORT_NUMBER 21
-#define IRC_CONTROL_PORT_NUMBER_1 6667
-#define IRC_CONTROL_PORT_NUMBER_2 6668
-
-/*
-   The following macro is used to update an
-   internet checksum.  "delta" is a 32-bit
-   accumulation of all the changes to the
-   checksum (adding in new 16-bit words and
-   subtracting out old words), and "cksum"
-   is the checksum value to be updated.
-*/
-#define ADJUST_CHECKSUM(acc, cksum) { \
-    acc += cksum; \
-    if (acc < 0) \
-    { \
-        acc = -acc; \
-        acc = (acc >> 16) + (acc & 0xffff); \
-        acc += acc >> 16; \
-        cksum = (u_short) ~acc; \
-    } \
-    else \
-    { \
-        acc = (acc >> 16) + (acc & 0xffff); \
-        acc += acc >> 16; \
-        cksum = (u_short) acc; \
-    } \
-}
-
-
-
-
-/* TCP Handling Routines
-
-    TcpMonitorIn()  -- These routines monitor TCP connections, and
-    TcpMonitorOut() -- delete a link node when a connection is closed.
-
-These routines look for SYN, ACK and RST flags to determine when TCP
-connections open and close.  When a TCP connection closes, the data
-structure containing packet aliasing information is deleted after
-a timeout period.
-*/
-
-/* Local prototypes */
-static void TcpMonitorIn(struct ip *, struct alias_link *);
-
-static void TcpMonitorOut(struct ip *, struct alias_link *);
-
-
-static void
-TcpMonitorIn(struct ip *pip, struct alias_link *link)
-{
-    struct tcphdr *tc;
-
-    tc = (struct tcphdr *) ((char *) pip + (pip->ip_hl << 2));
-
-    switch (GetStateIn(link))
-    {
-        case ALIAS_TCP_STATE_NOT_CONNECTED:
-            if (tc->th_flags & TH_SYN)
-                SetStateIn(link, ALIAS_TCP_STATE_CONNECTED);
-            break;
-        case ALIAS_TCP_STATE_CONNECTED:
-            if (tc->th_flags & TH_FIN
-                || tc->th_flags & TH_RST)
-                SetStateIn(link, ALIAS_TCP_STATE_DISCONNECTED);
-            break;
-    }
-}
-
-static void
-TcpMonitorOut(struct ip *pip, struct alias_link *link)
-{
-    struct tcphdr *tc;
-
-    tc = (struct tcphdr *) ((char *) pip + (pip->ip_hl << 2));
-     
-    switch (GetStateOut(link))
-    {
-        case ALIAS_TCP_STATE_NOT_CONNECTED:
-            if (tc->th_flags & TH_SYN)
-                SetStateOut(link, ALIAS_TCP_STATE_CONNECTED);
-            break;
-        case ALIAS_TCP_STATE_CONNECTED:
-            if (tc->th_flags & TH_FIN
-                || tc->th_flags & TH_RST)
-                SetStateOut(link, ALIAS_TCP_STATE_DISCONNECTED);
-            break;
-    }
-}
-
-
-
-
-
-/* Protocol Specific Packet Aliasing Routines 
-
-    IcmpAliasIn(), IcmpAliasIn1(), IcmpAliasIn2(), IcmpAliasIn3()
-    IcmpAliasOut(), IcmpAliasOut1(), IcmpAliasOut2(), IcmpAliasOut3()
-    UdpAliasIn(), UdpAliasOut()
-    TcpAliasIn(), TcpAliasOut()
-
-These routines handle protocol specific details of packet aliasing.
-One may observe a certain amount of repetitive arithmetic in these
-functions, the purpose of which is to compute a revised checksum
-without actually summing over the entire data packet, which could be
-unnecessarily time consuming.
-
-The purpose of the packet aliasing routines is to replace the source
-address of the outgoing packet and then correctly put it back for
-any incoming packets.  For TCP and UDP, ports are also re-mapped.
-
-For ICMP echo/timestamp requests and replies, the following scheme
-is used: the id number is replaced by an alias for the outgoing
-packet.
-
-ICMP error messages are handled by looking at the IP fragment
-in the data section of the message.
-
-For TCP and UDP protocols, a port number is chosen for an outgoing
-packet, and then incoming packets are identified by IP address and
-port numbers.  For TCP packets, there is additional logic in the event
-that sequence and ack numbers have been altered (as is the case for
-FTP data port commands).
-
-The port numbers used by the packet aliasing module are not true
-ports in the Unix sense.  No sockets are actually bound to ports.
-They are more correctly thought of as placeholders.
-
-All packets go through the aliasing mechanism, whether they come from
-the gateway machine or other machines on a local area network.
-*/
-
-
-/* Local prototypes */
-static int IcmpAliasIn1(struct ip *);
-static int IcmpAliasIn2(struct ip *);
-static int IcmpAliasIn3(struct ip *);
-static int IcmpAliasIn (struct ip *);
-
-static int IcmpAliasOut1(struct ip *);
-static int IcmpAliasOut2(struct ip *);
-static int IcmpAliasOut3(struct ip *);
-static int IcmpAliasOut (struct ip *);
-
-static int UdpAliasOut(struct ip *);
-static int UdpAliasIn (struct ip *);
-
-static int TcpAliasOut(struct ip *, int);
-static int TcpAliasIn (struct ip *);
-
-
-static int
-IcmpAliasIn1(struct ip *pip)
-{
-/*
-    De-alias incoming echo and timestamp replies
-*/
-    struct alias_link *link;
-    struct icmp *ic;
-
-    ic = (struct icmp *) ((char *) pip + (pip->ip_hl << 2));
-
-/* Get source address from ICMP data field and restore original data */
-    link = FindIcmpIn(pip->ip_src, pip->ip_dst, ic->icmp_id);
-    if (link != NULL)
-    {
-        u_short original_id;
-        int accumulate;
-
-        original_id = GetOriginalPort(link);
-
-/* Adjust ICMP checksum */
-        accumulate  = ic->icmp_id;
-        accumulate -= original_id;
-        ADJUST_CHECKSUM(accumulate, ic->icmp_cksum)
-
-/* Put original sequence number back in */
-        ic->icmp_id = original_id;
-
-/* Put original address back into IP header */
-        {
-            struct in_addr original_address;
-
-            original_address = GetOriginalAddress(link);
-            DifferentialChecksum(&pip->ip_sum,
-                                 (u_short *) &original_address,
-                                 (u_short *) &pip->ip_dst,
-                                 2);
-            pip->ip_dst = original_address;
-        }
-
-        return(PKT_ALIAS_OK);
-    }
-    return(PKT_ALIAS_IGNORED);
-}
-
-static int
-IcmpAliasIn2(struct ip *pip)
-{
-/*
-    Alias incoming ICMP error messages containing
-    IP header and first 64 bits of datagram.
-*/
-    struct ip *ip;
-    struct icmp *ic, *ic2;
-    struct udphdr *ud;
-    struct tcphdr *tc;
-    struct alias_link *link;
-
-    ic = (struct icmp *) ((char *) pip + (pip->ip_hl << 2));
-    ip = (struct ip *) ic->icmp_data;
-
-    ud = (struct udphdr *) ((char *) ip + (ip->ip_hl <<2));
-    tc = (struct tcphdr *) ud;
-    ic2 = (struct icmp *) ud;
-
-    if (ip->ip_p == IPPROTO_UDP)
-        link = FindUdpTcpIn(ip->ip_dst, ip->ip_src,
-                            ud->uh_dport, ud->uh_sport,
-                            IPPROTO_UDP);
-    else if (ip->ip_p == IPPROTO_TCP)
-        link = FindUdpTcpIn(ip->ip_dst, ip->ip_src,
-                            tc->th_dport, tc->th_sport,
-                            IPPROTO_TCP);
-    else if (ip->ip_p == IPPROTO_ICMP) {
-        if (ic2->icmp_type == ICMP_ECHO || ic2->icmp_type == ICMP_TSTAMP)
-            link = FindIcmpIn(ip->ip_dst, ip->ip_src, ic2->icmp_id);
-         else
-            link = NULL;
-    } else
-        link = NULL;
-
-    if (link != NULL)
-    {
-        if (ip->ip_p == IPPROTO_UDP || ip->ip_p == IPPROTO_TCP)
-        {
-            u_short *sptr;
-            int accumulate;
-            struct in_addr original_address;
-            u_short original_port;
-
-            original_address = GetOriginalAddress(link);
-            original_port = GetOriginalPort(link);
-    
-/* Adjust ICMP checksum */
-            sptr = (u_short *) &(ip->ip_src);
-            accumulate  = *sptr++;
-            accumulate += *sptr;
-            sptr = (u_short *) &original_address;
-            accumulate -= *sptr++;
-            accumulate -= *sptr;
-            accumulate += ud->uh_sport;
-            accumulate -= original_port;
-            ADJUST_CHECKSUM(accumulate, ic->icmp_cksum)
-
-/* Un-alias address in IP header */
-            DifferentialChecksum(&pip->ip_sum,
-                                 (u_short *) &original_address,
-                                 (u_short *) &pip->ip_dst,
-                                 2);
-            pip->ip_dst = original_address;
-
-/* Un-alias address and port number of original IP packet
-fragment contained in ICMP data section */
-            ip->ip_src = original_address;
-            ud->uh_sport = original_port; 
-        }
-        else if (pip->ip_p == IPPROTO_ICMP)
-        {
-            u_short *sptr;
-            int accumulate;
-            struct in_addr original_address;
-            u_short original_id;
-
-            original_address = GetOriginalAddress(link);
-            original_id = GetOriginalPort(link);
-
-/* Adjust ICMP checksum */
-            sptr = (u_short *) &(ip->ip_src);
-            accumulate  = *sptr++;
-            accumulate += *sptr;
-            sptr = (u_short *) &original_address;
-            accumulate -= *sptr++;
-            accumulate -= *sptr;
-            accumulate += ic2->icmp_id;
-            accumulate -= original_id;
-            ADJUST_CHECKSUM(accumulate, ic->icmp_cksum)
-
-/* Un-alias address in IP header */
-            DifferentialChecksum(&pip->ip_sum,
-                                 (u_short *) &original_address,
-                                 (u_short *) &pip->ip_dst,
-                                 2);
-            pip->ip_dst = original_address;
-
-/* Un-alias address of original IP packet and seqence number of 
-   embedded icmp datagram */
-            ip->ip_src = original_address;
-            ic2->icmp_id = original_id;
-        }
-        return(PKT_ALIAS_OK);
-    }
-    return(PKT_ALIAS_IGNORED);
-}
-
-
-static int
-IcmpAliasIn3(struct ip *pip)
-{
-    struct in_addr original_address;
-
-    original_address = FindOriginalAddress(pip->ip_dst);
-    DifferentialChecksum(&pip->ip_sum,
-                         (u_short *) &original_address,
-                         (u_short *) &pip->ip_dst,
-                         2);
-    pip->ip_dst = original_address;
-
-    return PKT_ALIAS_OK;
-}
-
-
-static int
-IcmpAliasIn(struct ip *pip)
-{
-    int iresult;
-    struct icmp *ic;
-
-    ic = (struct icmp *) ((char *) pip + (pip->ip_hl << 2));
-
-    iresult = PKT_ALIAS_IGNORED;
-    switch (ic->icmp_type)
-    {
-        case ICMP_ECHOREPLY:
-        case ICMP_TSTAMPREPLY:
-            if (ic->icmp_code == 0)
-            {
-                iresult = IcmpAliasIn1(pip);
-            }
-            break;
-        case ICMP_UNREACH:
-        case ICMP_SOURCEQUENCH:
-        case ICMP_TIMXCEED:
-        case ICMP_PARAMPROB:
-            iresult = IcmpAliasIn2(pip);
-            break;
-        case ICMP_ECHO:
-        case ICMP_TSTAMP:
-            iresult = IcmpAliasIn3(pip);
-            break;
-    }
-    return(iresult);
-}
-
-
-static int
-IcmpAliasOut1(struct ip *pip)
-{
-/*
-    Alias ICMP echo and timestamp packets
-*/
-    struct alias_link *link;
-    struct icmp *ic;
-
-    ic = (struct icmp *) ((char *) pip + (pip->ip_hl << 2));
-
-/* Save overwritten data for when echo packet returns */
-    link = FindIcmpOut(pip->ip_src, pip->ip_dst, ic->icmp_id);
-    if (link != NULL)
-    {
-        u_short alias_id;
-        int accumulate;
-
-        alias_id = GetAliasPort(link);
-
-/* Since data field is being modified, adjust ICMP checksum */
-        accumulate  = ic->icmp_id;
-        accumulate -= alias_id;
-        ADJUST_CHECKSUM(accumulate, ic->icmp_cksum)
-
-/* Alias sequence number */
-        ic->icmp_id = alias_id;
-
-/* Change source address */
-        {
-            struct in_addr alias_address;
-
-            alias_address = GetAliasAddress(link);
-            DifferentialChecksum(&pip->ip_sum,
-                                 (u_short *) &alias_address,
-                                 (u_short *) &pip->ip_src,
-                                 2);
-            pip->ip_src = alias_address;
-        }
-
-        return(PKT_ALIAS_OK);
-    }
-    return(PKT_ALIAS_IGNORED);
-}
-
-
-static int
-IcmpAliasOut2(struct ip *pip)
-{
-/*
-    Alias outgoing ICMP error messages containing
-    IP header and first 64 bits of datagram.
-*/
-    struct in_addr alias_addr;
-    struct ip *ip;
-    struct icmp *ic;
-
-    ic = (struct icmp *) ((char *) pip + (pip->ip_hl << 2));
-    ip = (struct ip *) ic->icmp_data;
-
-    alias_addr = FindAliasAddress(ip->ip_src);
-
-/* Alias destination address in IP fragment */
-    DifferentialChecksum(&ic->icmp_cksum,
-                         (u_short *) &alias_addr,
-                         (u_short *) &ip->ip_dst,
-                         2);
-    ip->ip_dst = alias_addr;
-
-/* alias source address in IP header */
-    DifferentialChecksum(&pip->ip_sum,
-                         (u_short *) &alias_addr,
-                         (u_short *) &pip->ip_src,
-                         2);
-    pip->ip_src = alias_addr;
-
-    return PKT_ALIAS_OK;
-}
-
-
-static int
-IcmpAliasOut3(struct ip *pip)
-{
-/*
-  Handle outgoing echo and timestamp replies.  The
-  only thing which is done in this case is to alias
-  the source IP address of the packet.
-*/
-    struct in_addr alias_addr;
-
-    alias_addr = FindAliasAddress(pip->ip_src);
-    DifferentialChecksum(&pip->ip_sum,
-                         (u_short *) &alias_addr,
-                         (u_short *) &pip->ip_src,
-                         2);
-    pip->ip_src = alias_addr;
-
-    return PKT_ALIAS_OK;
-}
-
-
-static int
-IcmpAliasOut(struct ip *pip)
-{
-    int iresult;
-    struct icmp *ic;
-
-    ic = (struct icmp *) ((char *) pip + (pip->ip_hl << 2));
-
-    iresult = PKT_ALIAS_IGNORED;
-    switch (ic->icmp_type)
-    {
-        case ICMP_ECHO:
-        case ICMP_TSTAMP:
-            if (ic->icmp_code == 0)
-            {
-                iresult = IcmpAliasOut1(pip);
-            }
-            break;
-        case ICMP_UNREACH:
-        case ICMP_SOURCEQUENCH:
-        case ICMP_TIMXCEED:
-        case ICMP_PARAMPROB:
-            iresult = IcmpAliasOut2(pip);
-            break;
-        case ICMP_ECHOREPLY:
-        case ICMP_TSTAMPREPLY:
-            iresult = IcmpAliasOut3(pip);
-    }
-    return(iresult);
-}
-
-static int
-UdpAliasIn(struct ip *pip)
-{
-    struct udphdr *ud;
-    struct alias_link *link;
-
-    ud = (struct udphdr *) ((char *) pip + (pip->ip_hl << 2));
-
-    link = FindUdpTcpIn(pip->ip_src, pip->ip_dst,
-                        ud->uh_sport, ud->uh_dport,
-                        IPPROTO_UDP);
-    if (link != NULL)
-    {
-        struct in_addr alias_address;
-        struct in_addr original_address;
-        u_short alias_port;
-        int accumulate;
-        u_short *sptr;
-
-        alias_address = GetAliasAddress(link);
-        original_address = GetOriginalAddress(link);
-        alias_port = ud->uh_dport;
-        ud->uh_dport = GetOriginalPort(link);
-
-/* If UDP checksum is not zero, then adjust since destination port */
-/* is being unaliased and destination port is being altered.       */
-        if (ud->uh_sum != 0)
-        {
-            accumulate  = alias_port;
-            accumulate -= ud->uh_dport;
-            sptr = (u_short *) &alias_address;
-            accumulate += *sptr++;
-            accumulate += *sptr;
-            sptr = (u_short *) &original_address;
-            accumulate -= *sptr++;
-            accumulate -= *sptr;
-            ADJUST_CHECKSUM(accumulate, ud->uh_sum)
-        }
-
-/* Restore original IP address */
-        DifferentialChecksum(&pip->ip_sum,
-                             (u_short *) &original_address,
-                             (u_short *) &pip->ip_dst,
-                             2);
-        pip->ip_dst = original_address;
-        return(PKT_ALIAS_OK);
-    }
-    return(PKT_ALIAS_IGNORED);
-}
-
-static int
-UdpAliasOut(struct ip *pip)
-{
-    struct udphdr *ud;
-    struct alias_link *link;
-
-    ud = (struct udphdr *) ((char *) pip + (pip->ip_hl << 2));
-
-    link = FindUdpTcpOut(pip->ip_src, pip->ip_dst,
-                         ud->uh_sport, ud->uh_dport,
-                         IPPROTO_UDP);
-    if (link != NULL)
-    {
-        u_short alias_port;
-        struct in_addr alias_address;
-
-        alias_address = GetAliasAddress(link);
-        alias_port = GetAliasPort(link);
-
-/* If UDP checksum is not zero, adjust since source port is */
-/* being aliased and source address is being altered        */
-        if (ud->uh_sum != 0)
-        {
-            int accumulate;
-            u_short *sptr;
-
-            accumulate  = ud->uh_sport;
-            accumulate -= alias_port;
-            sptr = (u_short *) &(pip->ip_src);
-            accumulate += *sptr++;
-            accumulate += *sptr;
-            sptr = (u_short *) &alias_address;
-            accumulate -= *sptr++;
-            accumulate -= *sptr;
-            ADJUST_CHECKSUM(accumulate, ud->uh_sum)
-        }
-
-/* Put alias port in TCP header */
-        ud->uh_sport = alias_port;
-
-/* Change source address */
-        DifferentialChecksum(&pip->ip_sum,
-                             (u_short *) &alias_address,
-                             (u_short *) &pip->ip_src,
-                             2);
-        pip->ip_src = alias_address;
-
-        return(PKT_ALIAS_OK);
-    }
-    return(PKT_ALIAS_IGNORED);
-}
-
-
-
-static int
-TcpAliasIn(struct ip *pip)
-{
-    struct tcphdr *tc;
-    struct alias_link *link;
-
-    tc = (struct tcphdr *) ((char *) pip + (pip->ip_hl << 2));
-
-    link = FindUdpTcpIn(pip->ip_src, pip->ip_dst,
-                        tc->th_sport, tc->th_dport,
-                        IPPROTO_TCP);
-    if (link != NULL)
-    {
-        struct in_addr alias_address;
-        struct in_addr original_address;
-        u_short alias_port;
-        int accumulate;
-        u_short *sptr;
-
-        alias_address = GetAliasAddress(link);
-        original_address = GetOriginalAddress(link);
-        alias_port = tc->th_dport;
-        tc->th_dport = GetOriginalPort(link);
-
-/* Adjust TCP checksum since destination port is being unaliased */
-/* and destination port is being altered.                        */
-        accumulate  = alias_port;
-        accumulate -= tc->th_dport;
-        sptr = (u_short *) &alias_address;
-        accumulate += *sptr++;
-        accumulate += *sptr;
-        sptr = (u_short *) &original_address;
-        accumulate -= *sptr++;
-        accumulate -= *sptr;
-
-/* See if ack number needs to be modified */
-        if (GetAckModified(link) == 1)
-        {
-            int delta;
-
-            delta = GetDeltaAckIn(pip, link);
-            if (delta != 0)
-            {
-                sptr = (u_short *) &tc->th_ack;
-                accumulate += *sptr++;
-                accumulate += *sptr;
-                tc->th_ack = htonl(ntohl(tc->th_ack) - delta);
-                sptr = (u_short *) &tc->th_ack;
-                accumulate -= *sptr++;
-                accumulate -= *sptr;
-            }
-        }
-
-        ADJUST_CHECKSUM(accumulate, tc->th_sum);
-
-/* Restore original IP address */
-        DifferentialChecksum(&pip->ip_sum,
-                             (u_short *) &original_address,
-                             (u_short *) &pip->ip_dst,
-                             2);
-        pip->ip_dst = original_address;
-
-/* Monitor TCP connection state */
-        TcpMonitorIn(pip, link);
-
-        return(PKT_ALIAS_OK);
-    }
-    return(PKT_ALIAS_IGNORED);
-}
-
-static int
-TcpAliasOut(struct ip *pip, int maxpacketsize)
-{
-    struct tcphdr *tc;
-    struct alias_link *link;
-
-    tc = (struct tcphdr *) ((char *) pip + (pip->ip_hl << 2));
-
-    link = FindUdpTcpOut(pip->ip_src, pip->ip_dst,
-                         tc->th_sport, tc->th_dport,
-                         IPPROTO_TCP);
-    if (link !=NULL)
-    {
-        struct in_addr alias_address;
-        u_short alias_port;
-        int accumulate;
-        u_short *sptr;
-
-        alias_port = GetAliasPort(link);
-        alias_address = GetAliasAddress(link);
-
-/* Monitor tcp connection state */
-        TcpMonitorOut(pip, link);
-
-/* Special processing for ftp connection */
-        if (ntohs(tc->th_dport) == FTP_CONTROL_PORT_NUMBER
-         || ntohs(tc->th_sport) == FTP_CONTROL_PORT_NUMBER)
-            AliasHandleFtpOut(pip, link, maxpacketsize);
-        if (ntohs(tc->th_dport) == IRC_CONTROL_PORT_NUMBER_1
-                        || ntohs(tc->th_dport) == IRC_CONTROL_PORT_NUMBER_2)
-            AliasHandleIrcOut(pip, link, maxpacketsize);
-
-/* Adjust TCP checksum since source port is being aliased */
-/* and source address is being altered                    */
-        accumulate  = tc->th_sport;
-        accumulate -= alias_port;
-        sptr = (u_short *) &(pip->ip_src);
-        accumulate += *sptr++;
-        accumulate += *sptr;
-        sptr = (u_short *) &alias_address;
-        accumulate -= *sptr++;
-        accumulate -= *sptr;
-
-/* Modify sequence number if necessary */
-        if (GetAckModified(link) == 1)
-        {
-            int delta;
-
-            delta = GetDeltaSeqOut(pip, link);
-            if (delta != 0)
-            {
-                sptr = (u_short *) &tc->th_seq;
-                accumulate += *sptr++;
-                accumulate += *sptr;
-                tc->th_seq = htonl(ntohl(tc->th_seq) + delta);
-                sptr = (u_short *) &tc->th_seq;
-                accumulate -= *sptr++;
-                accumulate -= *sptr;
-            }
-        }
-
-        ADJUST_CHECKSUM(accumulate, tc->th_sum)
-
-/* Put alias address in TCP header */
-        tc->th_sport = alias_port;
-
-/* Change source address */
-        DifferentialChecksum(&pip->ip_sum,
-                             (u_short *) &alias_address,
-                             (u_short *) &pip->ip_src,
-                             2);
-        pip->ip_src = alias_address;
-
-        return(PKT_ALIAS_OK);
-    }
-    return(PKT_ALIAS_IGNORED);
-}
-
-
-
-
-/* Fragment Handling
-
-    FragmentIn()
-    FragmentOut()
-
-The packet aliasing module has a limited ability for handling IP
-fragments.  If the ICMP, TCP or UDP header is in the first fragment
-received, then the id number of the IP packet is saved, and other
-fragments are identified according to their ID number and IP address
-they were sent from.  Pointers to unresolved fragments can also be
-saved and recalled when a header fragment is seen.
-*/
-
-/* Local prototypes */
-static int FragmentIn(struct ip *);
-static int FragmentOut(struct ip *);
-
-
-static int
-FragmentIn(struct ip *pip)
-{
-    struct alias_link *link;
-
-    link = FindFragmentIn2(pip->ip_src, pip->ip_dst, pip->ip_id);
-    if (link != NULL)
-    {
-        struct in_addr original_address;
-
-        GetFragmentAddr(link, &original_address);
-        DifferentialChecksum(&pip->ip_sum,
-                             (u_short *) &original_address,
-                             (u_short *) &pip->ip_dst,
-                             2);
-        pip->ip_dst = original_address; 
-   
-        return(PKT_ALIAS_OK);
-    }
-    return(PKT_ALIAS_UNRESOLVED_FRAGMENT);
-}
-
-
-static int
-FragmentOut(struct ip *pip)
-{
-    struct in_addr alias_address;
-
-    alias_address = FindAliasAddress(pip->ip_src);
-    DifferentialChecksum(&pip->ip_sum,
-                         (u_short *) &alias_address,
-                         (u_short *) &pip->ip_src,
-                          2);
-    pip->ip_src = alias_address;
-
-    return(PKT_ALIAS_OK);
-}
-
-
-
-
-
-
-/* Outside World Access
-
-        PacketAliasSaveFragment()
-        PacketAliasGetFragment()
-        PacketAliasFragmentIn()
-        PacketAliasIn()
-        PacketAliasOut()
-
-(prototypes in alias.h)
-*/
-
-
-int
-PacketAliasSaveFragment(char *ptr)
-{
-    int iresult;
-    struct alias_link *link;
-    struct ip *pip;
-
-    pip = (struct ip *) ptr;
-    link = AddFragmentPtrLink(pip->ip_src, pip->ip_id);
-    iresult = PKT_ALIAS_ERROR;
-    if (link != NULL)
-    {
-        SetFragmentPtr(link, ptr);
-        iresult = PKT_ALIAS_OK;
-    }
-    return(iresult);
-}
-
-
-char *
-PacketAliasGetFragment(char *ptr)
-{
-    struct alias_link *link;
-    char *fptr;
-    struct ip *pip;
-
-    pip = (struct ip *) ptr;
-    link = FindFragmentPtr(pip->ip_src, pip->ip_id);
-    if (link != NULL)
-    {
-        GetFragmentPtr(link, &fptr);
-        SetFragmentPtr(link, NULL);
-        SetExpire(link, 0); /* Deletes link */
-
-        return(fptr);
-    }
-    else
-    {
-        return(NULL);
-    }
-}
-
-
-void
-PacketAliasFragmentIn(char *ptr,          /* Points to correctly de-aliased
-                                             header fragment */
-                      char *ptr_fragment  /* Points to fragment which must
-                                             be de-aliased   */
-                     )
-{
-    struct ip *pip;
-    struct ip *fpip;
-
-    pip = (struct ip *) ptr;
-    fpip = (struct ip *) ptr_fragment;
-
-    DifferentialChecksum(&fpip->ip_sum,
-                         (u_short *) &pip->ip_dst,
-                         (u_short *) &fpip->ip_dst,
-                         2);
-    fpip->ip_dst = pip->ip_dst;
-}
-
-
-int
-PacketAliasIn(char *ptr, int maxpacketsize)
-{
-    struct in_addr alias_addr;
-    struct ip *pip;
-    int iresult;
-
-    HouseKeeping();
-    ClearCheckNewLink();
-    pip = (struct ip *) ptr;
-    alias_addr = pip->ip_dst;
-        
-    /* Defense against mangled packets */
-    if (ntohs(pip->ip_len) > maxpacketsize
-     || (pip->ip_hl<<2) > maxpacketsize)
-        return PKT_ALIAS_IGNORED;
-        
-    iresult = PKT_ALIAS_IGNORED;
-    if ( (ntohs(pip->ip_off) & IP_OFFMASK) == 0 )
-    {
-        switch (pip->ip_p)
-        {
-            case IPPROTO_ICMP:
-                iresult = IcmpAliasIn(pip);
-                break;
-            case IPPROTO_UDP:
-                iresult = UdpAliasIn(pip);
-                break;
-            case IPPROTO_TCP:
-                iresult = TcpAliasIn(pip);
-                break;
-        }
-
-        if (ntohs(pip->ip_off) & IP_MF)
-        {
-            struct alias_link *link;
-
-            link = FindFragmentIn1(pip->ip_src, alias_addr, pip->ip_id);
-            if (link != NULL)
-            {
-                iresult = PKT_ALIAS_FOUND_HEADER_FRAGMENT;
-                SetFragmentAddr(link, pip->ip_dst);
-            }
-            else
-            {
-                iresult = PKT_ALIAS_ERROR;
-            }
-        }
-    }
-    else
-    {
-        iresult = FragmentIn(pip);
-    }
-
-    return(iresult);
-}
-
-
-
-/* Unregistered address ranges */
-
-/* 10.0.0.0   ->   10.255.255.255 */
-#define UNREG_ADDR_A_LOWER 0x0a000000
-#define UNREG_ADDR_A_UPPER 0x0affffff
-
-/* 172.16.0.0  ->  172.31.255.255 */
-#define UNREG_ADDR_B_LOWER 0xac100000
-#define UNREG_ADDR_B_UPPER 0xac1fffff
-
-/* 192.168.0.0 -> 192.168.255.255 */
-#define UNREG_ADDR_C_LOWER 0xc0a80000
-#define UNREG_ADDR_C_UPPER 0xc0a8ffff
-
-
-
-int
-PacketAliasOut(char *ptr,           /* valid IP packet */
-               int  maxpacketsize   /* How much the packet data may grow
-                                       (FTP and IRC inline changes) */
-              )
-{
-    int iresult;
-    struct in_addr addr_save;
-    struct ip *pip;
-
-    HouseKeeping();
-    ClearCheckNewLink();
-    pip = (struct ip *) ptr;
-
-    /* Defense against mangled packets */
-    if (ntohs(pip->ip_len) > maxpacketsize
-     || (pip->ip_hl<<2) > maxpacketsize)
-        return PKT_ALIAS_IGNORED;
-
-    addr_save = GetDefaultAliasAddress();
-    if (packetAliasMode & PKT_ALIAS_UNREGISTERED_ONLY)
-    {
-        unsigned int addr;
-        int iclass;
-
-        iclass = 0;
-        addr = ntohl(pip->ip_src.s_addr);
-        if      (addr >= UNREG_ADDR_C_LOWER && addr <= UNREG_ADDR_C_UPPER)
-            iclass = 3;
-        else if (addr >= UNREG_ADDR_B_LOWER && addr <= UNREG_ADDR_B_UPPER)
-            iclass = 2;
-        else if (addr >= UNREG_ADDR_A_LOWER && addr <= UNREG_ADDR_A_UPPER)
-            iclass = 1;
-
-        if (iclass == 0)
-        {
-            SetDefaultAliasAddress(pip->ip_src);
-        }
-    }
-
-    iresult = PKT_ALIAS_IGNORED;
-    if ((ntohs(pip->ip_off) & IP_OFFMASK) == 0)
-    {
-        switch (pip->ip_p)
-        {
-            case IPPROTO_ICMP:
-                iresult = IcmpAliasOut(pip);
-                break;
-            case IPPROTO_UDP:
-                iresult = UdpAliasOut(pip);
-                break;
-            case IPPROTO_TCP:
-                iresult = TcpAliasOut(pip, maxpacketsize);
-                break;
-        }
-    }
-    else
-    {
-        iresult = FragmentOut(pip);
-    }
-
-    SetDefaultAliasAddress(addr_save);
-    return(iresult);
-}
diff --git a/usr.sbin/ppp/libalias/alias.h b/usr.sbin/ppp/libalias/alias.h
deleted file mode 100644
index 35a966c5348..00000000000
--- a/usr.sbin/ppp/libalias/alias.h
+++ /dev/null
@@ -1,173 +0,0 @@
-/*lint -save -library Flexelint comment for external headers */
-
-/*
-    Alias.h defines the outside world interfaces for the packet
-    aliasing software.
-
-    This software is placed into the public domain with no restrictions
-    on its distribution.
-
-    $Id: alias.h,v 1.1 1998/04/25 09:23:37 brian Exp $
-*/
-
-
-#ifndef _ALIAS_H_
-#define _ALIAS_H_
-
-#ifndef NULL
-#define NULL 0
-#endif
-
-/* Alias link representative (incomplete struct) */
-struct alias_link;
-
-/* External interfaces (API) to packet aliasing engine */
-
-/* Initialization and Control */
-    extern void
-    PacketAliasInit(void);
-
-    extern void
-    PacketAliasUninit(void);
-
-    extern void
-    PacketAliasSetAddress(struct in_addr);
-
-    extern unsigned int
-    PacketAliasSetMode(unsigned int, unsigned int);
-
-#ifndef NO_FW_PUNCH
-    extern void
-    PacketAliasSetFWBase(unsigned int, unsigned int);
-#endif
-
-/* Packet Handling */
-    extern int
-    PacketAliasIn(char *, int maxpacketsize);
-
-    extern int
-    PacketAliasOut(char *, int maxpacketsize);
-
-/* Port and Address Redirection */
-    extern struct alias_link *
-    PacketAliasRedirectPort(struct in_addr, u_short, 
-                            struct in_addr, u_short,
-                            struct in_addr, u_short,
-                            u_char);
-
-    extern struct alias_link *
-    PacketAliasRedirectAddr(struct in_addr,
-                            struct in_addr);
-
-    extern void
-    PacketAliasRedirectDelete(struct alias_link *);
-
-/* Fragment Handling */
-    extern int
-    PacketAliasSaveFragment(char *);
-
-    extern char *
-    PacketAliasGetFragment(char *);
-
-    extern void 
-    PacketAliasFragmentIn(char *, char *);
-
-/* Miscellaneous Functions */
-    extern void
-    PacketAliasSetTarget(struct in_addr addr);
-
-    extern int
-    PacketAliasCheckNewLink(void);
-
-    extern u_short
-    PacketAliasInternetChecksum(u_short *, int);
-
-
-/*
-   In version 2.2, the function names were rationalized
-   to all be of the form PacketAlias...  These are the
-   old function names for backwards compatibility
-*/
-extern int SaveFragmentPtr(char *);
-extern char *GetNextFragmentPtr(char *);
-extern void FragmentAliasIn(char *, char *);
-extern void SetPacketAliasAddress(struct in_addr);
-extern void InitPacketAlias(void);
-extern unsigned int SetPacketAliasMode(unsigned int, unsigned int);
-extern int PacketAliasIn2(char *, struct in_addr, int maxpacketsize);
-extern int PacketAliasOut2(char *, struct in_addr, int maxpacketsize);
-extern int
-PacketAliasPermanentLink(struct in_addr, u_short, 
-                         struct in_addr, u_short,
-                         u_short, u_char);
-extern u_short InternetChecksum(u_short *, int);
-
-/* Obsolete constant */
-#define PKT_ALIAS_NEW_LINK 5
-
-/********************** Mode flags ********************/
-/* Set these flags using SetPacketAliasMode() */
-
-/* If PKT_ALIAS_LOG is set, a message will be printed to
-	/var/log/alias.log every time a link is created or deleted.  This
-	is useful for debugging */
-#define PKT_ALIAS_LOG 0x01
-
-/* If PKT_ALIAS_DENY_INCOMING is set, then incoming connections (e.g.
-	to ftp, telnet or web servers will be prevented by the aliasing
-	mechanism.  */
-#define PKT_ALIAS_DENY_INCOMING 0x02
-
-/* If PKT_ALIAS_SAME_PORTS is set, packets will be attempted sent from
-	the same port as they originated on.  This allows eg rsh to work
-	*99% of the time*, but _not_ 100%.  (It will be slightly flakey
-	instead of not working at all.)  This mode bit is set by
-        PacketAliasInit(), so it is a default mode of operation. */
-#define PKT_ALIAS_SAME_PORTS 0x04
-
-/* If PKT_ALIAS_USE_SOCKETS is set, then when partially specified
-	links (e.g. destination port and/or address is zero), the packet
-	aliasing engine will attempt to allocate a socket for the aliasing
-	port it chooses.  This will avoid interference with the host
-	machine.  Fully specified links do not require this.  This bit
-        is set after a call to PacketAliasInit(), so it is a default
-        mode of operation.*/
-#define PKT_ALIAS_USE_SOCKETS 0x08
-
-/* If PKT_ALIAS_UNREGISTERED_ONLY is set, then only packets with with
-	unregistered source addresses will be aliased (along with those
-	of the ppp host maching itself.  Private addresses are those
-        in the following ranges:
-
-		10.0.0.0     ->   10.255.255.255
-		172.16.0.0   ->   172.31.255.255
-		192.168.0.0  ->   192.168.255.255  */
-#define PKT_ALIAS_UNREGISTERED_ONLY 0x10
-
-/* If PKT_ALIAS_RESET_ON_ADDR_CHANGE is set, then the table of dynamic
-	aliasing links will be reset whenever PacketAliasSetAddress()
-        changes the default aliasing address.  If the default aliasing
-        address is left unchanged by this functions call, then the
-        table of dynamic aliasing links will be left intact.  This
-        bit is set after a call to PacketAliasInit(). */
-#define PKT_ALIAS_RESET_ON_ADDR_CHANGE 0x20
-
-#ifndef NO_FW_PUNCH
-/* If PKT_ALIAS_PUNCH_FW is set, active FTP and IRC DCC connections
-   will create a 'hole' in the firewall to allow the transfers to
-   work.  Where (IPFW "line-numbers") the hole is created is
-   controlled by PacketAliasSetFWBase(base, size). The hole will be
-   attached to that particular alias_link, so when the link goes away
-   so do the hole.  */
-#define PKT_ALIAS_PUNCH_FW 0x40
-#endif
-
-/* Return Codes */
-#define PKT_ALIAS_ERROR -1
-#define PKT_ALIAS_OK 1
-#define PKT_ALIAS_IGNORED 2
-#define PKT_ALIAS_UNRESOLVED_FRAGMENT 3
-#define PKT_ALIAS_FOUND_HEADER_FRAGMENT 4
-
-#endif
-/*lint -restore */
diff --git a/usr.sbin/ppp/libalias/alias_db.c b/usr.sbin/ppp/libalias/alias_db.c
deleted file mode 100644
index 7bbb19122be..00000000000
--- a/usr.sbin/ppp/libalias/alias_db.c
+++ /dev/null
@@ -1,2239 +0,0 @@
-/*  -*- mode: c; tab-width: 8; c-basic-indent: 4; -*-
-    Alias_db.c encapsulates all data structures used for storing
-    packet aliasing data.  Other parts of the aliasing software
-    access data through functions provided in this file.
-
-    Data storage is based on the notion of a "link", which is
-    established for ICMP echo/reply packets, UDP datagrams and
-    TCP stream connections.  A link stores the original source
-    and destination addresses.  For UDP and TCP, it also stores
-    source and destination port numbers, as well as an alias
-    port number.  Links are also used to store information about
-    fragments.
-
-    There is a facility for sweeping through and deleting old
-    links as new packets are sent through.  A simple timeout is
-    used for ICMP and UDP links.  TCP links are left alone unless
-    there is an incomplete connection, in which case the link
-    can be deleted after a certain amount of time.
-
-
-    This software is placed into the public domain with no restrictions
-    on its distribution.
-
-    Initial version: August, 1996  (cjm)
-
-    Version 1.4: September 16, 1996 (cjm)
-        Facility for handling incoming links added.
-
-    Version 1.6: September 18, 1996 (cjm)
-        ICMP data handling simplified.
-
-    Version 1.7: January 9, 1997 (cjm)
-        Fragment handling simplified.
-        Saves pointers for unresolved fragments.
-        Permits links for unspecied remote ports
-          or unspecified remote addresses.
-        Fixed bug which did not properly zero port
-          table entries after a link was deleted.
-        Cleaned up some obsolete comments.
-
-    Version 1.8: January 14, 1997 (cjm)
-        Fixed data type error in StartPoint().
-        (This error did not exist prior to v1.7
-        and was discovered and fixed by Ari Suutari)
-
-    Version 1.9: February 1, 1997
-        Optionally, connections initiated from packet aliasing host
-        machine will will not have their port number aliased unless it
-        conflicts with an aliasing port already being used. (cjm)
-
-        All options earlier being #ifdef'ed now are available through
-        a new interface, SetPacketAliasMode().  This allow run time
-        control (which is now available in PPP+pktAlias through the
-        'alias' keyword). (ee)
-
-        Added ability to create an alias port without
-        either destination address or port specified.
-        port type = ALIAS_PORT_UNKNOWN_DEST_ALL (ee)
- 
-        Removed K&R style function headers
-        and general cleanup. (ee)
-
-        Added packetAliasMode to replace compiler #defines's (ee)
- 
-        Allocates sockets for partially specified
-        ports if ALIAS_USE_SOCKETS defined. (cjm)
-
-    Version 2.0: March, 1997
-        SetAliasAddress() will now clean up alias links
-        if the aliasing address is changed. (cjm)
-
-        PacketAliasPermanentLink() function added to support permanent
-        links.  (J. Fortes suggested the need for this.)
-        Examples:
-
-        (192.168.0.1, port 23)  <-> alias port 6002, unknown dest addr/port 
-
-        (192.168.0.2, port 21)  <-> alias port 3604, known dest addr
-                                                     unknown dest port 
-
-        These permament links allow for incoming connections to
-        machines on the local network.  They can be given with a
-        user-chosen amount of specificity, with increasing specificity
-        meaning more security. (cjm)
-
-        Quite a bit of rework to the basic engine.  The portTable[]
-        array, which kept track of which ports were in use was replaced
-        by a table/linked list structure. (cjm)
-
-        SetExpire() function added. (cjm)
-
-        DeleteLink() no longer frees memory association with a pointer
-        to a fragment (this bug was first recognized by E. Eklund in
-        v1.9).
-
-    Version 2.1: May, 1997 (cjm)
-        Packet aliasing engine reworked so that it can handle
-        multiple external addresses rather than just a single
-        host address.
-
-        PacketAliasRedirectPort() and PacketAliasRedirectAddr()
-        added to the API.  The first function is a more generalized
-        version of PacketAliasPermanentLink().  The second function
-        implements static network address translation.
-
-    See HISTORY file for additional revisions.
-*/
-
-
-/* System include files */
-#include <stdlib.h>
-#include <stdio.h>
-#include <unistd.h>
- 
-#include <sys/errno.h>
-#include <sys/socket.h>
-#include <sys/time.h>
-#include <sys/types.h>
-
-/* BSD network include files */
-#include <netinet/in_systm.h>
-#include <netinet/in.h>
-#include <netinet/ip.h>
-#include <netinet/tcp.h>
-#include <arpa/inet.h>
-
-#include "alias.h"
-#include "alias_local.h"
-
-
-
-/*
-   Constants (note: constants are also defined
-              near relevant functions or structs)
-*/
-
-/* Sizes of input and output link tables */
-#define LINK_TABLE_OUT_SIZE         101
-#define LINK_TABLE_IN_SIZE         4001
-
-/* Parameters used for cleanup of expired links */
-#define ALIAS_CLEANUP_INTERVAL_SECS  60       
-#define ALIAS_CLEANUP_MAX_SPOKES     30
-
-/* Timouts (in seconds) for different link types) */
-#define ICMP_EXPIRE_TIME             60
-#define UDP_EXPIRE_TIME              60
-#define FRAGMENT_ID_EXPIRE_TIME      10
-#define FRAGMENT_PTR_EXPIRE_TIME     30
-
-/* TCP link expire time for different cases */
-/* When the link has been used and closed - minimal grace time to
-   allow ACKs and potential re-connect in FTP (XXX - is this allowed?)  */
-#ifndef TCP_EXPIRE_DEAD
-#   define TCP_EXPIRE_DEAD           10
-#endif
-
-/* When the link has been used and closed on one side - the other side
-   is allowed to still send data */
-#ifndef TCP_EXPIRE_SINGLEDEAD
-#   define TCP_EXPIRE_SINGLEDEAD     90
-#endif
-
-/* When the link isn't yet up */
-#ifndef TCP_EXPIRE_INITIAL
-#   define TCP_EXPIRE_INITIAL       300
-#endif
-
-/* When the link is up */
-#ifndef TCP_EXPIRE_CONNECTED
-#   define TCP_EXPIRE_CONNECTED   86400
-#endif
-
-
-/* Dummy port number codes used for FindLinkIn/Out() and AddLink().
-   These constants can be anything except zero, which indicates an
-   unknown port numbea. */
-
-#define NO_DEST_PORT     1
-#define NO_SRC_PORT      1
-
-
-
-/* Data Structures 
-
-    The fundamental data structure used in this program is
-    "struct alias_link".  Whenever a TCP connection is made,
-    a UDP datagram is sent out, or an ICMP echo request is made,
-    a link record is made (if it has not already been created).
-    The link record is identified by the source address/port
-    and the destination address/port. In the case of an ICMP
-    echo request, the source port is treated as being equivalent
-    with the 16-bit id number of the ICMP packet.
-
-    The link record also can store some auxiliary data.  For
-    TCP connections that have had sequence and acknowledgment
-    modifications, data space is available to track these changes.
-    A state field is used to keep track in changes to the tcp
-    connection state.  Id numbers of fragments can also be
-    stored in the auxiliary space.  Pointers to unresolved
-    framgents can also be stored.
-
-    The link records support two independent chainings.  Lookup
-    tables for input and out tables hold the initial pointers
-    the link chains.  On input, the lookup table indexes on alias
-    port and link type.  On output, the lookup table indexes on
-    source addreess, destination address, source port, destination
-    port and link type.
-*/
-
-struct ack_data_record     /* used to save changes to ack/seq numbers */
-{
-    u_long ack_old;
-    u_long ack_new;
-    int delta;
-    int active;
-};
-
-struct tcp_state           /* Information about tcp connection        */
-{
-    int in;                /* State for outside -> inside             */
-    int out;               /* State for inside  -> outside            */
-    int index;             /* Index to ack data array                 */
-    int ack_modified;      /* Indicates whether ack and seq numbers   */
-                           /* been modified                           */
-};
-
-#define N_LINK_TCP_DATA   3 /* Number of distinct ack number changes
-                               saved for a modified TCP stream */
-struct tcp_dat
-{
-    struct tcp_state state;
-    struct ack_data_record ack[N_LINK_TCP_DATA];
-    int fwhole;             /* Which firewall record is used for this hole? */
-};
-
-struct alias_link                /* Main data structure */
-{
-    struct in_addr src_addr;     /* Address and port information        */
-    struct in_addr dst_addr;     /*  .                                  */
-    struct in_addr alias_addr;   /*  .                                  */
-    u_short src_port;            /*  .                                  */
-    u_short dst_port;            /*  .                                  */
-    u_short alias_port;          /*  .                                  */
-
-    int link_type;               /* Type of link: tcp, udp, icmp, frag  */
-
-/* values for link_type */
-#define LINK_ICMP                     1
-#define LINK_UDP                      2
-#define LINK_TCP                      3
-#define LINK_FRAGMENT_ID              4
-#define LINK_FRAGMENT_PTR             5
-#define LINK_ADDR                     6
-
-    int flags;                   /* indicates special characteristics   */
-
-/* flag bits */
-#define LINK_UNKNOWN_DEST_PORT     0x01
-#define LINK_UNKNOWN_DEST_ADDR     0x02
-#define LINK_PERMANENT             0x04
-#define LINK_PARTIALLY_SPECIFIED   0x03 /* logical-or of first two bits */
-#define LINK_UNFIREWALLED          0x08
-
-    int timestamp;               /* Time link was last accessed         */
-    int expire_time;             /* Expire time for link                */
-
-    int sockfd;                  /* socket descriptor                   */
-
-    u_int start_point_out;       /* Index number in output lookup table */
-    u_int start_point_in;
-    struct alias_link *next_out; /* Linked list pointers for input and  */
-    struct alias_link *last_out; /* output tables                       */
-    struct alias_link *next_in;  /*  .                                  */
-    struct alias_link *last_in;  /*  .                                  */
-
-    union                        /* Auxiliary data                      */
-    {
-        char *frag_ptr;
-        struct in_addr frag_addr;
-        struct tcp_dat *tcp;
-    } data;
-};
-
-
-
-
-
-/* Global Variables 
-
-    The global variables listed here are only accessed from
-    within alias_db.c and so are prefixed with the static 
-    designation.
-*/
-
-int packetAliasMode;                 /* Mode flags                      */ 
-                                     /*        - documented in alias.h  */
-
-static struct in_addr aliasAddress;  /* Address written onto source     */
-                                     /*   field of IP packet.           */
-
-static struct in_addr targetAddress; /* IP address incoming packets     */
-                                     /*   are sent to if no aliasing    */
-                                     /*   link already exists           */
-
-static struct in_addr nullAddress;   /* Used as a dummy parameter for   */
-                                     /*   some function calls           */
-static struct alias_link *
-linkTableOut[LINK_TABLE_OUT_SIZE];   /* Lookup table of pointers to     */
-                                     /*   chains of link records. Each  */
-static struct alias_link *           /*   link record is doubly indexed */
-linkTableIn[LINK_TABLE_IN_SIZE];     /*   into input and output lookup  */
-                                     /*   tables.                       */
-
-static int icmpLinkCount;            /* Link statistics                 */
-static int udpLinkCount;
-static int tcpLinkCount;
-static int fragmentIdLinkCount;
-static int fragmentPtrLinkCount;
-static int sockCount;
-
-static int cleanupIndex;             /* Index to chain of link table    */
-                                     /* being inspected for old links   */
-
-static int timeStamp;                /* System time in seconds for      */
-                                     /* current packet                  */
-
-static int lastCleanupTime;          /* Last time IncrementalCleanup()  */
-                                     /* was called                      */
-
-static int houseKeepingResidual;     /* used by HouseKeeping()          */
-
-static int deleteAllLinks;           /* If equal to zero, DeleteLink()  */
-                                     /* will not remove permanent links */
-
-static FILE *monitorFile;            /* File descriptor for link        */
-                                     /* statistics monitoring file      */
-
-static int newDefaultLink;           /* Indicates if a new aliasing     */
-                                     /* link has been created after a   */
-                                     /* call to PacketAliasIn/Out().    */
-             
-#ifndef NO_FW_PUNCH
-static int fireWallFD = -1;          /* File descriptor to be able to   */
-                                     /* control firewall.  Opened by    */
-                                     /* PacketAliasSetMode on first     */
-                                     /* setting the PKT_ALIAS_PUNCH_FW  */
-                                     /* flag.                           */
-#endif
-
-
-
-
-
-
-/* Internal utility routines (used only in alias_db.c)
-
-Lookup table starting points:
-    StartPointIn()           -- link table initial search point for
-                                outgoing packets
-    StartPointOut()          -- port table initial search point for
-                                incoming packets
-    
-Miscellaneous:
-    SeqDiff()                -- difference between two TCP sequences
-    ShowAliasStats()         -- send alias statistics to a monitor file
-*/
-
-
-/* Local prototypes */
-static u_int StartPointIn(struct in_addr, u_short, int);
-
-static u_int StartPointOut(struct in_addr, struct in_addr,
-                           u_short, u_short, int);
-
-static int SeqDiff(u_long, u_long);
-
-static void ShowAliasStats(void);
-
-#ifndef NO_FW_PUNCH
-/* Firewall control */
-static void InitPunchFW(void);
-static void UninitPunchFW(void);
-static void ClearFWHole(struct alias_link *link);
-#endif
-
-/* Log file control */
-static void InitPacketAliasLog(void);
-static void UninitPacketAliasLog(void);
-
-static u_int
-StartPointIn(struct in_addr alias_addr,
-             u_short alias_port,
-             int link_type)
-{
-    u_int n;
-
-    n  = alias_addr.s_addr;
-    n += alias_port;
-    n += link_type;
-    return(n % LINK_TABLE_IN_SIZE);
-}
-
-
-static u_int
-StartPointOut(struct in_addr src_addr, struct in_addr dst_addr,
-              u_short src_port, u_short dst_port, int link_type)
-{
-    u_int n;
-
-    n  = src_addr.s_addr;
-    n += dst_addr.s_addr;
-    n += src_port; 
-    n += dst_port;
-    n += link_type;
-
-    return(n % LINK_TABLE_OUT_SIZE);
-}
-
-
-static int
-SeqDiff(u_long x, u_long y)
-{
-/* Return the difference between two TCP sequence numbers */
-
-/*
-    This function is encapsulated in case there are any unusual
-    arithmetic conditions that need to be considered.
-*/
-
-    return (ntohl(y) - ntohl(x));
-}
-
-
-static void
-ShowAliasStats(void)
-{
-/* Used for debugging */
-
-   if (packetAliasMode & PKT_ALIAS_LOG)
-   {
-      fprintf(monitorFile, "icmp=%d, udp=%d, tcp=%d, frag_id=%d frag_ptr=%d",
-              icmpLinkCount,
-              udpLinkCount,
-              tcpLinkCount,
-              fragmentIdLinkCount,
-              fragmentPtrLinkCount);
-
-      fprintf(monitorFile, " / tot=%d  (sock=%d)\n",
-              icmpLinkCount + udpLinkCount
-                            + tcpLinkCount
-                            + fragmentIdLinkCount
-                            + fragmentPtrLinkCount,
-              sockCount);
-
-      fflush(monitorFile);
-   }
-}
-
-
-
-
-
-/* Internal routines for finding, deleting and adding links
-
-Port Allocation:
-    GetNewPort()             -- find and reserve new alias port number
-    GetSocket()              -- try to allocate a socket for a given port
-
-Link creation and deletion:
-    CleanupAliasData()      - remove all link chains from lookup table
-    IncrementalCleanup()    - look for stale links in a single chain
-    DeleteLink()            - remove link
-    AddLink()               - add link 
-    ReLink()                - change link 
-
-Link search:
-    FindLinkOut()           - find link for outgoing packets
-    FindLinkIn()            - find link for incoming packets
-*/
-
-/* Local prototypes */
-static int GetNewPort(struct alias_link *, int);
-
-static u_short GetSocket(u_short, int *, int);
-
-static void CleanupAliasData(void);
-
-static void IncrementalCleanup(void);
-
-static void DeleteLink(struct alias_link *);
-
-static struct alias_link *
-AddLink(struct in_addr, struct in_addr, struct in_addr,
-        u_short, u_short, int, int);
-
-static struct alias_link *
-ReLink(struct alias_link *,
-       struct in_addr, struct in_addr, struct in_addr,
-        u_short, u_short, int, int);
-
-static struct alias_link *
-FindLinkOut(struct in_addr, struct in_addr, u_short, u_short, int);
-
-static struct alias_link *
-FindLinkIn(struct in_addr, struct in_addr, u_short, u_short, int, int);
-
-
-#define ALIAS_PORT_BASE            0x08000
-#define ALIAS_PORT_MASK            0x07fff
-#define GET_NEW_PORT_MAX_ATTEMPTS       20
-
-#define GET_ALIAS_PORT                  -1
-#define GET_ALIAS_ID        GET_ALIAS_PORT
-
-/* GetNewPort() allocates port numbers.  Note that if a port number
-   is already in use, that does not mean that it cannot be used by
-   another link concurrently.  This is because GetNewPort() looks for
-   unused triplets: (dest addr, dest port, alias port). */
-
-static int
-GetNewPort(struct alias_link *link, int alias_port_param)
-{
-    int i;
-    int max_trials;
-    u_short port_sys;
-    u_short port_net;
-
-/*
-   Description of alias_port_param for GetNewPort().  When
-   this parameter is zero or positive, it precisely specifies
-   the port number.  GetNewPort() will return this number
-   without check that it is in use.
-
-   Whis this parameter is -1, it indicates to get a randomly
-   selected port number.
-*/
- 
-    if (alias_port_param == GET_ALIAS_PORT)
-    {
-        /*
-         * The aliasing port is automatically selected
-         * by one of two methods below:
-         */
-        max_trials = GET_NEW_PORT_MAX_ATTEMPTS;
-
-        if (packetAliasMode & PKT_ALIAS_SAME_PORTS)
-        {
-            /*
-             * When the ALIAS_SAME_PORTS option is
-             * chosen, the first try will be the
-             * actual source port. If this is already
-             * in use, the remainder of the trials
-             * will be random.
-             */
-            port_net = link->src_port;
-            port_sys = ntohs(port_net);
-        }
-        else
-        {
-            /* First trial and all subsequent are random. */
-            port_sys = random() & ALIAS_PORT_MASK;
-            port_sys += ALIAS_PORT_BASE;
-            port_net = htons(port_sys);
-        }
-    }
-    else if (alias_port_param >= 0 && alias_port_param < 0x10000)
-    {
-        link->alias_port = (u_short) alias_port_param;
-        return(0);
-    }
-    else
-    {
-        fprintf(stderr, "PacketAlias/GetNewPort(): ");
-        fprintf(stderr, "input parameter error\n");
-        return(-1);
-    }
-
-
-/* Port number search */
-    for (i=0; i<max_trials; i++)
-    {
-        int go_ahead;
-        struct alias_link *search_result;
-
-        search_result = FindLinkIn(link->dst_addr, link->alias_addr,
-                                   link->dst_port, port_net,
-                                   link->link_type, 0);
-
-        if (search_result == NULL)
-            go_ahead = 1;
-        else if (!(link->flags          & LINK_PARTIALLY_SPECIFIED)
-               && (search_result->flags & LINK_PARTIALLY_SPECIFIED))
-            go_ahead = 1;
-        else
-            go_ahead = 0;
-
-        if (go_ahead)
-        {
-            if ((packetAliasMode && PKT_ALIAS_USE_SOCKETS)
-             && (link->flags & LINK_PARTIALLY_SPECIFIED))
-            {
-                if (GetSocket(port_net, &link->sockfd, link->link_type))
-                {
-                    link->alias_port = port_net;
-                    return(0);
-                }
-            }
-            else
-            {
-                link->alias_port = port_net;
-                return(0);
-            }
-        }
-
-        port_sys = random() & ALIAS_PORT_MASK;
-        port_sys += ALIAS_PORT_BASE;
-        port_net = htons(port_sys);
-    }
-
-    fprintf(stderr, "PacketAlias/GetnewPort(): ");
-    fprintf(stderr, "could not find free port\n");
-
-    return(-1);
-}
-
-
-static u_short 
-GetSocket(u_short port_net, int *sockfd, int link_type)
-{
-    int err;
-    int sock;
-    struct sockaddr_in sock_addr;
-
-    if (link_type == LINK_TCP)
-        sock = socket(AF_INET, SOCK_STREAM, 0);
-    else if (link_type == LINK_UDP)
-        sock = socket(AF_INET, SOCK_DGRAM, 0);
-    else
-    {
-        fprintf(stderr, "PacketAlias/GetSocket(): ");
-        fprintf(stderr, "incorrect link type\n");
-        return(0);
-    }
-
-    if (sock < 0)
-    {
-        fprintf(stderr, "PacketAlias/GetSocket(): ");
-        fprintf(stderr, "socket() error %d\n", *sockfd);
-        return(0);
-    }
-
-    sock_addr.sin_family = AF_INET;
-    sock_addr.sin_addr.s_addr = htonl(INADDR_ANY);
-    sock_addr.sin_port = port_net;
-
-    err = bind(sock,
-               (struct sockaddr *) &sock_addr,
-               sizeof(sock_addr));
-    if (err == 0)
-    {
-        sockCount++;
-        *sockfd = sock;
-        return(1);
-    }
-    else
-    {
-        close(sock);
-        return(0);
-    }
-}
-
-
-static void
-CleanupAliasData(void)
-{
-    struct alias_link *link;
-    int i, icount;
-
-    icount = 0;
-    for (i=0; i<LINK_TABLE_OUT_SIZE; i++)
-    {
-        link = linkTableOut[i];
-        while (link != NULL)
-        {
-            struct alias_link *link_next;
-            link_next = link->next_out;
-            icount++;
-            DeleteLink(link);
-            link = link_next;
-        }
-    }
-
-    cleanupIndex =0;
-}
-
-
-static void
-IncrementalCleanup(void)
-{
-    int icount;
-    struct alias_link *link;
-
-    icount = 0;
-    link = linkTableOut[cleanupIndex++];
-    while (link != NULL)
-    {
-        int idelta;
-        struct alias_link *link_next;
-
-        link_next = link->next_out; 
-        idelta = timeStamp - link->timestamp;
-        switch (link->link_type)
-        {
-            case LINK_ICMP:
-            case LINK_UDP:
-            case LINK_FRAGMENT_ID:
-            case LINK_FRAGMENT_PTR:
-                if (idelta > link->expire_time)
-                {
-                    DeleteLink(link);
-                    icount++;
-                }
-                break;
-            case LINK_TCP:
-                if (idelta > link->expire_time)
-                {
-                    struct tcp_dat *tcp_aux;
-
-                    tcp_aux = link->data.tcp; 
-                    if (tcp_aux->state.in  != ALIAS_TCP_STATE_CONNECTED
-                     || tcp_aux->state.out != ALIAS_TCP_STATE_CONNECTED)
-                    {
-                        DeleteLink(link);
-                        icount++;
-                    }
-                }
-                break;
-        }
-        link = link_next;
-    }
-
-    if (cleanupIndex == LINK_TABLE_OUT_SIZE)
-        cleanupIndex = 0;
-}
-
-void
-DeleteLink(struct alias_link *link)
-{
-    struct alias_link *link_last;
-    struct alias_link *link_next;
-
-/* Don't do anything if the link is marked permanent */
-    if (deleteAllLinks == 0 && link->flags & LINK_PERMANENT)
-        return;
-
-#ifndef NO_FW_PUNCH
-/* Delete associatied firewall hole, if any */
-    ClearFWHole(link);
-#endif
-
-/* Adjust output table pointers */
-    link_last = link->last_out;
-    link_next = link->next_out;
-
-    if (link_last != NULL)
-        link_last->next_out = link_next;
-    else
-        linkTableOut[link->start_point_out] = link_next;
-
-    if (link_next != NULL)
-        link_next->last_out = link_last;
-
-/* Adjust input table pointers */
-    link_last = link->last_in;
-    link_next = link->next_in;
-
-    if (link_last != NULL)
-        link_last->next_in = link_next;
-    else
-        linkTableIn[link->start_point_in] = link_next;
-
-    if (link_next != NULL)
-        link_next->last_in = link_last;
-
-/* Close socket, if one has been allocated */
-    if (link->sockfd != -1)
-    {
-        sockCount--;
-        close(link->sockfd);
-    }
-
-/* Link-type dependent cleanup */
-    switch(link->link_type)
-    {
-        case LINK_ICMP:
-            icmpLinkCount--;
-            break;
-        case LINK_UDP:
-            udpLinkCount--;
-            break;
-        case LINK_TCP:
-            tcpLinkCount--;
-            if (link->data.tcp != NULL)
-                free(link->data.tcp);
-            break;
-        case LINK_FRAGMENT_ID:
-            fragmentIdLinkCount--;
-            break;
-        case LINK_FRAGMENT_PTR:
-            fragmentPtrLinkCount--;
-            if (link->data.frag_ptr != NULL)
-                free(link->data.frag_ptr);
-            break;
-    }
-
-/* Free memory */
-    free(link);
-
-/* Write statistics, if logging enabled */
-    if (packetAliasMode & PKT_ALIAS_LOG)
-    {
-        ShowAliasStats();
-    }
-}
-
-
-static struct alias_link *
-AddLink(struct in_addr  src_addr,
-        struct in_addr  dst_addr,
-        struct in_addr  alias_addr,
-        u_short         src_port,
-        u_short         dst_port,
-        int             alias_port_param,  /* if less than zero, alias   */
-        int             link_type)         /* port will be automatically */
-{                                          /* chosen. If greater than    */
-    u_int start_point;                     /* zero, equal to alias port  */
-    struct alias_link *link;
-    struct alias_link *first_link;
-
-    link = malloc(sizeof(struct alias_link));
-    if (link != NULL)
-    {
-    /* If either the aliasing address or source address are
-       equal to the default device address (equal to the
-       global variable aliasAddress), then set the alias
-       address field of the link record to zero */
-
-        if (src_addr.s_addr == aliasAddress.s_addr)
-            src_addr.s_addr = 0;
-
-        if (alias_addr.s_addr == aliasAddress.s_addr)
-            alias_addr.s_addr = 0;
-
-    /* Basic initialization */
-        link->src_addr    = src_addr;
-        link->dst_addr    = dst_addr;
-        link->src_port    = src_port;
-        link->alias_addr  = alias_addr;
-        link->dst_port    = dst_port;
-        link->link_type   = link_type;
-        link->sockfd      = -1;
-        link->flags       = 0;
-        link->timestamp   = timeStamp;
-
-    /* Expiration time */
-        switch (link_type)
-        {
-        case LINK_ICMP:
-            link->expire_time = ICMP_EXPIRE_TIME;
-            break;
-        case LINK_UDP:
-            link->expire_time = UDP_EXPIRE_TIME;
-            break;
-        case LINK_TCP:
-            link->expire_time = TCP_EXPIRE_INITIAL;
-            break;
-        case LINK_FRAGMENT_ID:
-            link->expire_time = FRAGMENT_ID_EXPIRE_TIME;
-            break;
-        case LINK_FRAGMENT_PTR:
-            link->expire_time = FRAGMENT_PTR_EXPIRE_TIME;
-            break;
-        }
-
-    /* Determine alias flags */
-        if (dst_addr.s_addr == 0)
-            link->flags |= LINK_UNKNOWN_DEST_ADDR;
-        if (dst_port == 0)
-            link->flags |= LINK_UNKNOWN_DEST_PORT;
-
-    /* Determine alias port */
-        if (GetNewPort(link, alias_port_param) != 0)
-        {
-            free(link);
-            return(NULL);
-        }
-
-    /* Set up pointers for output lookup table */
-        start_point = StartPointOut(src_addr, dst_addr, 
-                                    src_port, dst_port, link_type);
-        first_link = linkTableOut[start_point];
-
-        link->last_out        = NULL;
-        link->next_out        = first_link;
-        link->start_point_out = start_point;
-
-        if (first_link != NULL)
-            first_link->last_out = link;
-
-        linkTableOut[start_point] = link;
-
-    /* Set up pointers for input lookup table */
-        start_point = StartPointIn(alias_addr, link->alias_port, link_type); 
-        first_link = linkTableIn[start_point];
-
-        link->last_in        = NULL;
-        link->next_in        = first_link;
-        link->start_point_in = start_point;
-
-        if (first_link != NULL)
-            first_link->last_in = link;
-
-        linkTableIn[start_point] = link;
-
-    /* Link-type dependent initialization */
-        switch(link_type)
-        {
-            struct tcp_dat  *aux_tcp;
-
-            case LINK_ICMP:
-                icmpLinkCount++;
-                break;
-            case LINK_UDP:
-                udpLinkCount++;
-                break;
-            case LINK_TCP:
-                aux_tcp = malloc(sizeof(struct tcp_dat));
-                link->data.tcp = aux_tcp;
-                if (aux_tcp != NULL)
-                {
-                    int i;
-
-                    tcpLinkCount++;
-                    aux_tcp->state.in = ALIAS_TCP_STATE_NOT_CONNECTED;
-                    aux_tcp->state.out = ALIAS_TCP_STATE_NOT_CONNECTED;
-                    aux_tcp->state.index = 0;
-                    aux_tcp->state.ack_modified = 0;
-                    for (i=0; i<N_LINK_TCP_DATA; i++)
-                        aux_tcp->ack[i].active = 0;
-                    aux_tcp->fwhole = -1;
-                }
-                else
-                {
-                    fprintf(stderr, "PacketAlias/AddLink: ");
-                    fprintf(stderr, " cannot allocate auxiliary TCP data\n");
-                }
-                break;
-            case LINK_FRAGMENT_ID:
-                fragmentIdLinkCount++;
-                break;
-            case LINK_FRAGMENT_PTR:
-                fragmentPtrLinkCount++;
-                break;
-        }
-    }
-    else
-    {
-        fprintf(stderr, "PacketAlias/AddLink(): ");
-        fprintf(stderr, "malloc() call failed.\n");
-    }
-
-    if (packetAliasMode & PKT_ALIAS_LOG)
-    {
-        ShowAliasStats();
-    }
-
-    return(link);
-}
-
-static struct alias_link *
-ReLink(struct alias_link *old_link,
-       struct in_addr  src_addr,
-       struct in_addr  dst_addr,
-       struct in_addr  alias_addr,
-       u_short         src_port,
-       u_short         dst_port,
-       int             alias_port_param,   /* if less than zero, alias   */
-       int             link_type)          /* port will be automatically */
-{                                          /* chosen. If greater than    */
-    struct alias_link *new_link;           /* zero, equal to alias port  */
-
-    new_link = AddLink(src_addr, dst_addr, alias_addr,
-                       src_port, dst_port, alias_port_param,
-                       link_type);
-#ifndef NO_FW_PUNCH
-    if (new_link != NULL &&
-        old_link->link_type == LINK_TCP &&
-        old_link->data.tcp &&
-        old_link->data.tcp->fwhole > 0) {
-      PunchFWHole(new_link);
-    }
-#endif
-    DeleteLink(old_link);
-    return new_link;
-}
-
-static struct alias_link *
-FindLinkOut(struct in_addr src_addr,
-            struct in_addr dst_addr,
-            u_short src_port,
-            u_short dst_port,
-            int link_type)
-{
-    u_int i;
-    struct alias_link *link;
-
-    if (src_addr.s_addr == aliasAddress.s_addr)
-        src_addr.s_addr = 0;
-
-    i = StartPointOut(src_addr, dst_addr, src_port, dst_port, link_type);
-    link = linkTableOut[i];
-    while (link != NULL)
-    {
-        if (link->src_addr.s_addr == src_addr.s_addr
-         && link->dst_addr.s_addr == dst_addr.s_addr
-         && link->dst_port        == dst_port
-         && link->src_port        == src_port
-         && link->link_type       == link_type)
-        {
-            link->timestamp = timeStamp;
-            break;
-        }
-        link = link->next_out;
-    }
-
-    return(link);
-}
-
-
-struct alias_link *
-FindLinkIn(struct in_addr  dst_addr,
-           struct in_addr  alias_addr,
-           u_short         dst_port,
-           u_short         alias_port,
-           int             link_type,
-           int             replace_partial_links)
-{
-    int flags_in;
-    u_int start_point;
-    struct alias_link *link;
-    struct alias_link *link_fully_specified;
-    struct alias_link *link_unknown_all;
-    struct alias_link *link_unknown_dst_addr;
-    struct alias_link *link_unknown_dst_port;
-
-/* Initialize pointers */
-    link_fully_specified  = NULL;
-    link_unknown_all      = NULL;
-    link_unknown_dst_addr = NULL;
-    link_unknown_dst_port = NULL;
-
-/* If either the dest addr or port is unknown, the search
-   loop will have to know about this. */
-
-    flags_in = 0;
-    if (dst_addr.s_addr == 0)
-        flags_in |= LINK_UNKNOWN_DEST_ADDR;
-    if (dst_port == 0)
-        flags_in |= LINK_UNKNOWN_DEST_PORT;
-
-/* The following allows permanent links to be
-   be specified as using the default aliasing address
-   (i.e. device interface address) without knowing
-   in advance what that address is. */
-
-    if (alias_addr.s_addr == aliasAddress.s_addr)
-        alias_addr.s_addr = 0;
-
-/* Search loop */
-    start_point = StartPointIn(alias_addr, alias_port, link_type);
-    link = linkTableIn[start_point];
-    while (link != NULL)
-    {
-        int flags;
-
-        flags = flags_in | link->flags;
-        if (!(flags & LINK_PARTIALLY_SPECIFIED))
-        {
-            if (link->alias_addr.s_addr == alias_addr.s_addr
-             && link->alias_port        == alias_port 
-             && link->dst_addr.s_addr   == dst_addr.s_addr
-             && link->dst_port          == dst_port
-             && link->link_type         == link_type)
-            {
-                link_fully_specified = link;
-                break;
-            }
-        }
-        else if ((flags & LINK_UNKNOWN_DEST_ADDR)
-              && (flags & LINK_UNKNOWN_DEST_PORT))
-        {
-            if (link->alias_addr.s_addr == alias_addr.s_addr
-             && link->alias_port        == alias_port
-             && link->link_type         == link_type)
-            {
-                if (link_unknown_all == NULL)
-                    link_unknown_all = link;
-            }
-        }
-        else if (flags & LINK_UNKNOWN_DEST_ADDR)
-        {
-            if (link->alias_addr.s_addr == alias_addr.s_addr
-             && link->alias_port        == alias_port
-             && link->link_type         == link_type
-             && link->dst_port          == dst_port)
-            {
-                if (link_unknown_dst_addr == NULL)
-                    link_unknown_dst_addr = link;
-            }
-        }
-        else if (flags & LINK_UNKNOWN_DEST_PORT)
-        {
-            if (link->alias_addr.s_addr == alias_addr.s_addr
-             && link->alias_port        == alias_port
-             && link->link_type         == link_type
-             && link->dst_addr.s_addr   == dst_addr.s_addr)
-            {
-                if (link_unknown_dst_port == NULL)
-                    link_unknown_dst_port = link;
-            }
-        }
-        link = link->next_in;
-    }
-
-
-
-    if (link_fully_specified != NULL)
-    {
-        return link_fully_specified;
-    }
-    else if (link_unknown_dst_port != NULL)
-    {
-        return replace_partial_links
-          ? ReLink(link_unknown_dst_port,
-                   link_unknown_dst_port->src_addr, dst_addr, alias_addr,
-                   link_unknown_dst_port->src_port, dst_port, alias_port,
-                   link_type)
-          : link_unknown_dst_port;
-    }
-    else if (link_unknown_dst_addr != NULL)
-    {
-        return replace_partial_links
-          ? ReLink(link_unknown_dst_addr,
-                   link_unknown_dst_addr->src_addr, dst_addr, alias_addr,
-                   link_unknown_dst_addr->src_port, dst_port, alias_port,
-                   link_type)
-          : link_unknown_dst_addr;
-    }
-    else if (link_unknown_all != NULL)
-    {
-        return replace_partial_links
-          ? ReLink(link_unknown_all,
-                   link_unknown_all->src_addr, dst_addr, alias_addr,
-                   link_unknown_all->src_port, dst_port, alias_port,
-                   link_type)
-          : link_unknown_all;
-    }
-    else
-    {
-        return(NULL);
-    }
-}
-
-
-
-
-/* External routines for finding/adding links
-
--- "external" means outside alias_db.c, but within alias*.c --
-
-    FindIcmpIn(), FindIcmpOut()
-    FindFragmentIn1(), FindFragmentIn2()
-    AddFragmentPtrLink(), FindFragmentPtr()
-    FindUdpTcpIn(), FindUdpTcpOut()
-    FindOriginalAddress(), FindAliasAddress()
-
-(prototypes in alias_local.h)
-*/
-
-
-struct alias_link *
-FindIcmpIn(struct in_addr dst_addr,
-           struct in_addr alias_addr,
-           u_short id_alias)
-{
-    return FindLinkIn(dst_addr, alias_addr,
-                      NO_DEST_PORT, id_alias,
-                      LINK_ICMP, 0);
-}
-
-
-struct alias_link *
-FindIcmpOut(struct in_addr src_addr,
-            struct in_addr dst_addr,
-            u_short id)
-{
-    struct alias_link * link;
-
-    link = FindLinkOut(src_addr, dst_addr,
-                       id, NO_DEST_PORT,
-                       LINK_ICMP);
-    if (link == NULL)
-    {
-        struct in_addr alias_addr;
-
-        alias_addr = FindAliasAddress(src_addr);
-        link = AddLink(src_addr, dst_addr, alias_addr,
-                       id, NO_DEST_PORT, GET_ALIAS_ID,
-                       LINK_ICMP);
-    }
-
-    return(link);
-}
-
-
-struct alias_link *
-FindFragmentIn1(struct in_addr dst_addr,
-                struct in_addr alias_addr,
-                u_short ip_id)
-{
-    struct alias_link *link;
-
-    link = FindLinkIn(dst_addr, alias_addr,
-                      NO_DEST_PORT, ip_id,
-                      LINK_FRAGMENT_ID, 0);
-
-    if (link == NULL)
-    {
-        link = AddLink(nullAddress, dst_addr, alias_addr,
-                       NO_SRC_PORT, NO_DEST_PORT, ip_id,
-                       LINK_FRAGMENT_ID);
-    }
-
-    return(link);
-}
-
-
-struct alias_link *
-FindFragmentIn2(struct in_addr dst_addr,   /* Doesn't add a link if one */
-                struct in_addr alias_addr, /*   is not found.           */
-                u_short ip_id)
-{
-    return FindLinkIn(dst_addr, alias_addr,
-                      NO_DEST_PORT, ip_id,
-                      LINK_FRAGMENT_ID, 0);
-}
-
-
-struct alias_link *
-AddFragmentPtrLink(struct in_addr dst_addr,
-                   u_short ip_id)
-{
-    return AddLink(nullAddress, dst_addr, nullAddress,
-                   NO_SRC_PORT, NO_DEST_PORT, ip_id,
-                   LINK_FRAGMENT_PTR);
-}
-
-
-struct alias_link *
-FindFragmentPtr(struct in_addr dst_addr,
-                u_short ip_id)
-{
-    return FindLinkIn(dst_addr, nullAddress,
-                      NO_DEST_PORT, ip_id,
-                      LINK_FRAGMENT_PTR, 0);
-}
-
-
-struct alias_link *
-FindUdpTcpIn(struct in_addr dst_addr,
-             struct in_addr alias_addr,
-             u_short        dst_port,
-             u_short        alias_port,
-             u_char         proto)
-{
-    int link_type;
-    struct alias_link *link;
-
-    switch (proto)
-    {
-    case IPPROTO_UDP:
-        link_type = LINK_UDP;
-        break;
-    case IPPROTO_TCP:
-        link_type = LINK_TCP;
-        break;
-    default:
-        return NULL;
-        break;
-    }
-
-    link = FindLinkIn(dst_addr, alias_addr,
-                      dst_port, alias_port,
-                      link_type, 1);
-
-    if ( !(packetAliasMode & PKT_ALIAS_DENY_INCOMING) && link == NULL)
-    {
-        struct in_addr target_addr;
-
-        target_addr = FindOriginalAddress(alias_addr);
-        link = AddLink(target_addr, dst_addr, alias_addr,
-                       alias_port, dst_port, alias_port,
-                       link_type);
-    }
-
-    return(link);
-}
-
-
-struct alias_link * 
-FindUdpTcpOut(struct in_addr  src_addr,
-              struct in_addr  dst_addr,
-              u_short         src_port,
-              u_short         dst_port,
-              u_char          proto)
-{
-    int link_type;
-    struct alias_link *link;
-
-    switch (proto)
-    {
-    case IPPROTO_UDP:
-        link_type = LINK_UDP;
-        break;
-    case IPPROTO_TCP:
-        link_type = LINK_TCP;
-        break;
-    default:
-        return NULL;
-        break;
-    }
-
-    link = FindLinkOut(src_addr, dst_addr, src_port, dst_port, link_type);
-
-    if (link == NULL)
-    {
-        struct in_addr alias_addr;
-
-        alias_addr = FindAliasAddress(src_addr);
-        link = AddLink(src_addr, dst_addr, alias_addr,
-                       src_port, dst_port, GET_ALIAS_PORT,
-                       link_type);
-    }
-
-    return(link);
-}
-
-
-struct in_addr
-FindOriginalAddress(struct in_addr alias_addr)
-{
-    struct alias_link *link;
-    
-    link = FindLinkIn(nullAddress, alias_addr,
-                      0, 0, LINK_ADDR, 0);
-    if (link == NULL)
-    {
-        newDefaultLink = 1;
-        if (targetAddress.s_addr != 0)
-            return targetAddress;
-        else
-            return alias_addr;
-    }
-    else
-    {
-        if (link->src_addr.s_addr == 0)
-            return aliasAddress;
-        else
-            return link->src_addr;
-    }
-}
-
-
-struct in_addr
-FindAliasAddress(struct in_addr original_addr)
-{
-    struct alias_link *link;
-    
-    link = FindLinkOut(original_addr, nullAddress,
-                       0, 0, LINK_ADDR);
-    if (link == NULL)
-    {
-        return aliasAddress;
-    }
-    else
-    {
-        if (link->alias_addr.s_addr == 0)
-            return aliasAddress;
-        else
-            return link->alias_addr;
-    }
-}
-
-
-/* External routines for getting or changing link data
-   (external to alias_db.c, but internal to alias*.c)
-
-    SetFragmentData(), GetFragmentData()
-    SetFragmentPtr(), GetFragmentPtr()
-    SetStateIn(), SetStateOut(), GetStateIn(), GetStateOut()
-    GetOriginalAddress(), GetDestAddress(), GetAliasAddress()
-    GetOriginalPort(), GetAliasPort()
-    SetAckModified(), GetAckModified()
-    GetDeltaAckIn(), GetDeltaSeqOut(), AddSeq()
-*/
-
-
-void
-SetFragmentAddr(struct alias_link *link, struct in_addr src_addr)
-{
-    link->data.frag_addr = src_addr;
-}
-
-
-void
-GetFragmentAddr(struct alias_link *link, struct in_addr *src_addr)
-{
-    *src_addr = link->data.frag_addr;
-}
-
-
-void
-SetFragmentPtr(struct alias_link *link, char *fptr)
-{
-    link->data.frag_ptr = fptr;
-}
-
-
-void
-GetFragmentPtr(struct alias_link *link, char **fptr)
-{
-   *fptr = link->data.frag_ptr;
-}
-
-
-void
-SetStateIn(struct alias_link *link, int state)
-{
-    /* TCP input state */
-    switch (state) {
-    case ALIAS_TCP_STATE_DISCONNECTED:
-        if (link->data.tcp->state.out != ALIAS_TCP_STATE_CONNECTED) {
-            link->expire_time = TCP_EXPIRE_DEAD;
-        } else {
-            link->expire_time = TCP_EXPIRE_SINGLEDEAD;
-        }
-        link->data.tcp->state.in = state;
-        break;
-    case ALIAS_TCP_STATE_CONNECTED:
-        link->expire_time = TCP_EXPIRE_CONNECTED;
-        /*FALLTHROUGH*/
-    case ALIAS_TCP_STATE_NOT_CONNECTED:
-        link->data.tcp->state.in = state;
-        break;
-    default:
-        abort();
-    }
-}
-
-
-void
-SetStateOut(struct alias_link *link, int state)
-{
-    /* TCP output state */
-    switch (state) {
-    case ALIAS_TCP_STATE_DISCONNECTED:
-        if (link->data.tcp->state.in != ALIAS_TCP_STATE_CONNECTED) {
-            link->expire_time = TCP_EXPIRE_DEAD;
-        } else {
-            link->expire_time = TCP_EXPIRE_SINGLEDEAD;
-        }
-        link->data.tcp->state.out = state;
-        break;
-    case ALIAS_TCP_STATE_CONNECTED:
-        link->expire_time = TCP_EXPIRE_CONNECTED;
-        /*FALLTHROUGH*/
-    case ALIAS_TCP_STATE_NOT_CONNECTED:
-        link->data.tcp->state.out = state;
-        break;
-    default:
-        abort();
-    }
-}
-
-
-int
-GetStateIn(struct alias_link *link)
-{
-    /* TCP input state */
-    return link->data.tcp->state.in;
-}
-
-
-int
-GetStateOut(struct alias_link *link)
-{
-    /* TCP output state */
-    return link->data.tcp->state.out;
-}
-
-
-struct in_addr
-GetOriginalAddress(struct alias_link *link)
-{
-    if (link->src_addr.s_addr == 0)
-        return aliasAddress;
-    else
-        return(link->src_addr);
-}
-
-
-struct in_addr
-GetDestAddress(struct alias_link *link)
-{
-    return(link->dst_addr);
-}
-
-
-struct in_addr
-GetAliasAddress(struct alias_link *link)
-{
-    if (link->alias_addr.s_addr == 0)
-        return aliasAddress;
-    else
-        return link->alias_addr;
-}
-
-
-struct in_addr
-GetDefaultAliasAddress()
-{
-    return aliasAddress;
-}
-
-
-void
-SetDefaultAliasAddress(struct in_addr alias_addr)
-{
-    aliasAddress = alias_addr;
-}
-
-
-u_short
-GetOriginalPort(struct alias_link *link)
-{
-    return(link->src_port);
-}
-
-
-u_short
-GetAliasPort(struct alias_link *link)
-{
-    return(link->alias_port);
-}
-
-u_short
-GetDestPort(struct alias_link *link)
-{
-    return(link->dst_port);
-}
-
-void
-SetAckModified(struct alias_link *link)
-{
-/* Indicate that ack numbers have been modified in a TCP connection */
-    link->data.tcp->state.ack_modified = 1;
-}
-
-
-int
-GetAckModified(struct alias_link *link)
-{
-/* See if ack numbers have been modified */
-    return link->data.tcp->state.ack_modified;
-}
-
-
-int
-GetDeltaAckIn(struct ip *pip, struct alias_link *link)
-{
-/*
-Find out how much the ack number has been altered for an incoming
-TCP packet.  To do this, a circular list is ack numbers where the TCP
-packet size was altered is searched. 
-*/
-
-    int i;
-    struct tcphdr *tc;
-    int delta, ack_diff_min;
-    u_long ack;
-
-    tc = (struct tcphdr *) ((char *) pip + (pip->ip_hl << 2));
-    ack      = tc->th_ack;
-
-    delta = 0;
-    ack_diff_min = -1;
-    for (i=0; i<N_LINK_TCP_DATA; i++)
-    {
-        struct ack_data_record x;
-
-        x = link->data.tcp->ack[i];
-        if (x.active == 1)
-        {
-            int ack_diff;
-
-            ack_diff = SeqDiff(x.ack_new, ack);
-            if (ack_diff >= 0)
-            {
-                if (ack_diff_min >= 0)
-                {
-                    if (ack_diff < ack_diff_min)
-                    {
-                        delta = x.delta;
-                        ack_diff_min = ack_diff;
-                    }
-                }
-                else
-                {
-                    delta = x.delta;
-                    ack_diff_min = ack_diff;
-                }
-            }
-        }
-    }
-    return (delta);
-}
-
-
-int
-GetDeltaSeqOut(struct ip *pip, struct alias_link *link)
-{
-/*
-Find out how much the seq number has been altered for an outgoing
-TCP packet.  To do this, a circular list is ack numbers where the TCP
-packet size was altered is searched. 
-*/
-
-    int i;
-    struct tcphdr *tc;
-    int delta, seq_diff_min;
-    u_long seq;
-
-    tc = (struct tcphdr *) ((char *) pip + (pip->ip_hl << 2));
-    seq = tc->th_seq;
-
-    delta = 0;
-    seq_diff_min = -1;
-    for (i=0; i<N_LINK_TCP_DATA; i++)
-    {
-        struct ack_data_record x;
-
-        x = link->data.tcp->ack[i];
-        if (x.active == 1)
-        {
-            int seq_diff;
-
-            seq_diff = SeqDiff(x.ack_old, seq);
-            if (seq_diff >= 0)
-            {
-                if (seq_diff_min >= 0)
-                {
-                    if (seq_diff < seq_diff_min)
-                    {
-                        delta = x.delta;
-                        seq_diff_min = seq_diff;
-                    }
-                }
-                else
-                {
-                    delta = x.delta;
-                    seq_diff_min = seq_diff;
-                }
-            }
-        }
-    }
-    return (delta);
-}
-
-
-void
-AddSeq(struct ip *pip, struct alias_link *link, int delta)
-{
-/*
-When a TCP packet has been altered in length, save this
-information in a circular list.  If enough packets have
-been altered, then this list will begin to overwrite itself.
-*/
-
-    struct tcphdr *tc;
-    struct ack_data_record x;
-    int hlen, tlen, dlen;
-    int i;
-
-    tc = (struct tcphdr *) ((char *) pip + (pip->ip_hl << 2));
-
-    hlen = (pip->ip_hl + tc->th_off) << 2;
-    tlen = ntohs(pip->ip_len);
-    dlen = tlen - hlen;
-
-    x.ack_old = htonl(ntohl(tc->th_seq) + dlen);
-    x.ack_new = htonl(ntohl(tc->th_seq) + dlen + delta);
-    x.delta = delta;
-    x.active = 1;
-
-    i = link->data.tcp->state.index;
-    link->data.tcp->ack[i] = x;
-
-    i++;
-    if (i == N_LINK_TCP_DATA)
-        link->data.tcp->state.index = 0;
-    else
-        link->data.tcp->state.index = i;
-}
-
-void
-SetExpire(struct alias_link *link, int expire)
-{
-    if (expire == 0)
-    {
-        link->flags &= ~LINK_PERMANENT;
-        DeleteLink(link);
-    }
-    else if (expire == -1)
-    {
-        link->flags |= LINK_PERMANENT;
-    }
-    else if (expire > 0)
-    {
-        link->expire_time = expire;
-    }
-    else
-    {
-        fprintf(stderr, "PacketAlias/SetExpire(): ");
-        fprintf(stderr, "error in expire parameter\n");
-    }
-}
-
-void
-ClearCheckNewLink(void)
-{
-    newDefaultLink = 0;
-}
-
-
-/* Miscellaneous Functions
-
-    HouseKeeping()
-    InitPacketAliasLog()
-    UninitPacketAliasLog()
-*/
-
-/*
-    Whenever an outgoing or incoming packet is handled, HouseKeeping()
-    is called to find and remove timed-out aliasing links.  Logic exists
-    to sweep through the entire table and linked list structure
-    every 60 seconds.
-
-    (prototype in alias_local.h)
-*/
-
-void
-HouseKeeping(void)
-{
-    int i, n, n100;
-    struct timeval tv;
-    struct timezone tz;
-
-    /*
-     * Save system time (seconds) in global variable timeStamp for
-     * use by other functions. This is done so as not to unnecessarily
-     * waste timeline by making system calls.
-     */
-    gettimeofday(&tv, &tz);
-    timeStamp = tv.tv_sec;
-
-    /* Compute number of spokes (output table link chains) to cover */
-    n100  = LINK_TABLE_OUT_SIZE * 100 + houseKeepingResidual;
-    n100 *= timeStamp - lastCleanupTime;
-    n100 /= ALIAS_CLEANUP_INTERVAL_SECS;
-
-    n = n100/100;
-
-    /* Handle different cases */
-    if (n > ALIAS_CLEANUP_MAX_SPOKES)
-    {
-        n = ALIAS_CLEANUP_MAX_SPOKES;
-        lastCleanupTime = timeStamp;
-        houseKeepingResidual = 0;
-
-        for (i=0; i<n; i++)
-            IncrementalCleanup();
-    }
-    else if (n > 0)
-    {
-        lastCleanupTime = timeStamp;
-        houseKeepingResidual = n100 - 100*n;
-
-        for (i=0; i<n; i++)
-            IncrementalCleanup();
-    }
-    else if (n < 0)
-    {
-        fprintf(stderr, "PacketAlias/HouseKeeping(): ");
-        fprintf(stderr, "something unexpected in time values\n");
-        lastCleanupTime = timeStamp;
-        houseKeepingResidual = 0;
-    }
-}
-
-
-/* Init the log file and enable logging */
-static void
-InitPacketAliasLog(void)
-{
-   if ((~packetAliasMode & PKT_ALIAS_LOG)
-    && (monitorFile = fopen("/var/log/alias.log", "w")))
-   {
-      packetAliasMode |= PKT_ALIAS_LOG;
-      fprintf(monitorFile,
-      "PacketAlias/InitPacketAliasLog: Packet alias logging enabled.\n");
-   }
-}
-
-
-/* Close the log-file and disable logging. */
-static void
-UninitPacketAliasLog(void)
-{
-    if( monitorFile )
-        fclose(monitorFile);
-    packetAliasMode &= ~PKT_ALIAS_LOG;
-}
-
-
-
-
-
-
-/* Outside world interfaces
-
--- "outside world" means other than alias*.c routines --
-
-    PacketAliasRedirectPort()
-    PacketAliasRedirectAddr()
-    PacketAliasRedirectDelete()
-    PacketAliasSetAddress()
-    PacketAliasInit()
-    PacketAliasUninit()
-    PacketAliasSetMode()
-
-(prototypes in alias.h)
-*/
-
-/* Redirection from a specific public addr:port to a
-   a private addr:port */
-struct alias_link *
-PacketAliasRedirectPort(struct in_addr src_addr,   u_short src_port,
-                        struct in_addr dst_addr,   u_short dst_port,
-                        struct in_addr alias_addr, u_short alias_port,
-                        u_char proto)
-{
-    int link_type;
-    struct alias_link *link;
-
-    switch(proto)
-    {
-    case IPPROTO_UDP:
-        link_type = LINK_UDP;
-        break;
-    case IPPROTO_TCP:
-        link_type = LINK_TCP;
-        break;
-    default:
-        fprintf(stderr, "PacketAliasRedirectPort(): ");
-        fprintf(stderr, "only TCP and UDP protocols allowed\n");
-        return NULL;
-    }
-
-    link = AddLink(src_addr, dst_addr, alias_addr,
-                   src_port, dst_port, alias_port,
-                   link_type);
-
-    if (link != NULL)
-    {
-        link->flags |= LINK_PERMANENT;
-    }
-    else
-    {
-        fprintf(stderr, "PacketAliasRedirectPort(): " 
-                        "call to AddLink() failed\n");
-    }
-
-    return link;
-}
-
-
-/* Static address translation */
-struct alias_link *
-PacketAliasRedirectAddr(struct in_addr src_addr,
-                        struct in_addr alias_addr)
-{
-    struct alias_link *link;
-
-    link = AddLink(src_addr, nullAddress, alias_addr,
-                   0, 0, 0,
-                   LINK_ADDR);
-
-    if (link != NULL)
-    {
-        link->flags |= LINK_PERMANENT;
-    }
-    else
-    {
-        fprintf(stderr, "PacketAliasRedirectAddr(): " 
-                        "call to AddLink() failed\n");
-    }
-
-    return link;
-}
-
-
-void
-PacketAliasRedirectDelete(struct alias_link *link)
-{
-/* This is a dangerous function to put in the API,
-   because an invalid pointer can crash the program. */
-
-    deleteAllLinks = 1;
-    DeleteLink(link);
-    deleteAllLinks = 0;
-}
-
-
-void
-PacketAliasSetAddress(struct in_addr addr)
-{
-    if (packetAliasMode & PKT_ALIAS_RESET_ON_ADDR_CHANGE
-     && aliasAddress.s_addr != addr.s_addr)
-        CleanupAliasData();
-
-    aliasAddress = addr;
-}
-
-
-void
-PacketAliasSetTarget(struct in_addr target_addr)
-{
-    targetAddress = target_addr;
-}
-
-
-void
-PacketAliasInit(void)
-{
-    int i;
-    struct timeval tv;
-    struct timezone tz;
-    static int firstCall = 1;
-
-    if (firstCall == 1)
-    {
-        gettimeofday(&tv, &tz);
-        timeStamp = tv.tv_sec;
-        lastCleanupTime = tv.tv_sec;
-        houseKeepingResidual = 0;
-
-        for (i=0; i<LINK_TABLE_OUT_SIZE; i++)
-            linkTableOut[i] = NULL;
-        for (i=0; i<LINK_TABLE_IN_SIZE; i++)
-            linkTableIn[i] = NULL;
-
-        atexit(PacketAliasUninit);
-        firstCall = 0;
-    }
-    else
-    {
-        deleteAllLinks = 1;
-        CleanupAliasData();
-        deleteAllLinks = 0;
-    }
-
-    aliasAddress.s_addr = 0;
-    targetAddress.s_addr = 0;
-
-    icmpLinkCount = 0;
-    udpLinkCount = 0;
-    tcpLinkCount = 0;
-    fragmentIdLinkCount = 0;
-    fragmentPtrLinkCount = 0;
-    sockCount = 0;
-
-    cleanupIndex =0;
-
-    packetAliasMode = PKT_ALIAS_SAME_PORTS
-                    | PKT_ALIAS_USE_SOCKETS
-                    | PKT_ALIAS_RESET_ON_ADDR_CHANGE;
-}
-
-void
-PacketAliasUninit(void) {
-    deleteAllLinks = 1;
-    CleanupAliasData();
-    deleteAllLinks = 0;
-    UninitPacketAliasLog();
-#ifndef NO_FW_PUNCH
-    UninitPunchFW();
-#endif
-}
-
-
-/* Change mode for some operations */
-unsigned int
-PacketAliasSetMode(
-    unsigned int flags, /* Which state to bring flags to */
-    unsigned int mask   /* Mask of which flags to affect (use 0 to do a
-                           probe for flag values) */
-)
-{
-/* Enable logging? */
-    if (flags & mask & PKT_ALIAS_LOG)
-    {
-        InitPacketAliasLog();     /* Do the enable */
-    } else
-/* _Disable_ logging? */
-    if (~flags & mask & PKT_ALIAS_LOG) {
-        UninitPacketAliasLog();
-    }
-
-#ifndef NO_FW_PUNCH
-/* Start punching holes in the firewall? */
-    if (flags & mask & PKT_ALIAS_PUNCH_FW) {
-        InitPunchFW();
-    } else
-/* Stop punching holes in the firewall? */
-    if (~flags & mask & PKT_ALIAS_PUNCH_FW) {
-        UninitPunchFW();
-    }
-#endif
-
-/* Other flags can be set/cleared without special action */
-    packetAliasMode = (flags & mask) | (packetAliasMode & ~mask);
-    return packetAliasMode;
-}
-
-
-int
-PacketAliasCheckNewLink(void)
-{
-    return newDefaultLink;
-}
-
-
-#ifndef NO_FW_PUNCH
-
-/*****************
-  Code to support firewall punching.  This shouldn't really be in this
-  file, but making variables global is evil too.
-  ****************/
-
-/* Firewall include files */
-#include <sys/queue.h>
-#include <net/if.h>
-#include <netinet/ip_fw.h>
-#include <string.h>
-#include <err.h>
-
-static void ClearAllFWHoles(void);
-
-static int fireWallBaseNum;     /* The first firewall entry free for our use */
-static int fireWallNumNums;     /* How many entries can we use? */
-static int fireWallActiveNum;   /* Which entry did we last use? */
-static char *fireWallField;     /* bool array for entries */
-
-#define fw_setfield(field, num)                         \
-do {                                                    \
-    (field)[num] = 1;                                   \
-} /*lint -save -e717 */ while(0) /*lint -restore */
-#define fw_clrfield(field, num)                         \
-do {                                                    \
-    (field)[num] = 0;                                   \
-} /*lint -save -e717 */ while(0) /*lint -restore */
-#define fw_tstfield(field, num) ((field)[num])
-
-void
-PacketAliasSetFWBase(unsigned int base, unsigned int num) {
-    fireWallBaseNum = base;
-    fireWallNumNums = num;
-}
-
-static void
-InitPunchFW(void) {
-    fireWallField = malloc(fireWallNumNums);
-    if (fireWallField) {
-        memset(fireWallField, 0, fireWallNumNums);
-        if (fireWallFD < 0) {
-            fireWallFD = socket(AF_INET, SOCK_RAW, IPPROTO_RAW);
-        }
-        ClearAllFWHoles();
-        fireWallActiveNum = fireWallBaseNum;
-    }
-}
-
-static void
-UninitPunchFW(void) {
-    ClearAllFWHoles();
-    if (fireWallFD >= 0)
-        close(fireWallFD);
-    fireWallFD = -1;
-    if (fireWallField)
-        free(fireWallField);
-    fireWallField = NULL;
-    packetAliasMode &= ~PKT_ALIAS_PUNCH_FW;
-}
-
-/* Make a certain link go through the firewall */
-void
-PunchFWHole(struct alias_link *link) {
-    int r;                      /* Result code */
-    struct ip_fw rule;          /* On-the-fly built rule */
-    int fwhole;                 /* Where to punch hole */
-
-/* Don't do anything unless we are asked to */
-    if ( !(packetAliasMode & PKT_ALIAS_PUNCH_FW) ||
-         fireWallFD < 0 ||
-         link->link_type != LINK_TCP ||
-         !link->data.tcp)
-        return;
-
-    memset(&rule, 0, sizeof rule);
-
-/** Build rule **/
-
-    /* Find empty slot */
-    for (fwhole = fireWallActiveNum;
-         fwhole < fireWallBaseNum + fireWallNumNums &&
-             fw_tstfield(fireWallField, fwhole);
-         fwhole++)
-        ;
-    if (fwhole >= fireWallBaseNum + fireWallNumNums ||
-        fw_tstfield(fireWallField, fwhole)) {
-        for (fwhole = fireWallBaseNum;
-             fwhole < fireWallActiveNum &&
-                 fw_tstfield(fireWallField, fwhole);
-             fwhole++)
-            ;
-        if (fwhole == fireWallActiveNum) {
-            /* No rule point empty - we can't punch more holes. */
-            fireWallActiveNum = fireWallBaseNum;
-            fprintf(stderr, "libalias: Unable to create firewall hole!\n");
-            return;
-        }
-    }
-    /* Start next search at next position */
-    fireWallActiveNum = fwhole+1;
-
-    /* Build generic part of the two rules */
-    rule.fw_number = fwhole;
-    rule.fw_nports = 1;         /* Number of source ports; dest ports follow */
-    rule.fw_flg = IP_FW_F_ACCEPT;
-    rule.fw_prot = IPPROTO_TCP;
-    rule.fw_smsk.s_addr = INADDR_BROADCAST;
-    rule.fw_dmsk.s_addr = INADDR_BROADCAST;
-
-    /* Build and apply specific part of the rules */
-    rule.fw_src = GetOriginalAddress(link);
-    rule.fw_dst = GetDestAddress(link);
-    rule.fw_uar.fw_pts[0] = ntohs(GetOriginalPort(link));
-    rule.fw_uar.fw_pts[1] = ntohs(GetDestPort(link));
-
-    /* Skip non-bound links - XXX should not be strictly necessary,
-       but seems to leave hole if not done.  Leak of non-bound links?
-       (Code should be left even if the problem is fixed - it is a
-       clear optimization) */
-    if (rule.fw_uar.fw_pts[0] != 0 && rule.fw_uar.fw_pts[1] != 0) {
-        r = setsockopt(fireWallFD, IPPROTO_IP, IP_FW_ADD, &rule, sizeof rule);
-        if (r)
-            err(1, "alias punch inbound(1) setsockopt(IP_FW_ADD)");
-        rule.fw_src = GetDestAddress(link);
-        rule.fw_dst = GetOriginalAddress(link);
-        rule.fw_uar.fw_pts[0] = ntohs(GetDestPort(link));
-        rule.fw_uar.fw_pts[1] = ntohs(GetOriginalPort(link));
-        r = setsockopt(fireWallFD, IPPROTO_IP, IP_FW_ADD, &rule, sizeof rule);
-        if (r)
-            err(1, "alias punch inbound(2) setsockopt(IP_FW_ADD)");
-    }
-/* Indicate hole applied */
-    link->data.tcp->fwhole = fwhole;
-    fw_setfield(fireWallField, fwhole);
-}
-
-/* Remove a hole in a firewall associated with a particular alias
-   link.  Calling this too often is harmless. */
-static void
-ClearFWHole(struct alias_link *link) {
-    if (link->link_type == LINK_TCP && link->data.tcp) {
-        int fwhole =  link->data.tcp->fwhole; /* Where is the firewall hole? */
-        struct ip_fw rule;
-
-        if (fwhole < 0)
-            return;
-
-        memset(&rule, 0, sizeof rule);
-        rule.fw_number = fwhole;
-        while (!setsockopt(fireWallFD, IPPROTO_IP, IP_FW_DEL, &rule, sizeof rule))
-            ;
-        fw_clrfield(fireWallField, fwhole);
-        link->data.tcp->fwhole = -1;
-    }
-}
-
-/* Clear out the entire range dedicated to firewall holes. */
-static void
-ClearAllFWHoles(void) {
-    struct ip_fw rule;          /* On-the-fly built rule */
-    int i;
-    
-    if (fireWallFD < 0)
-        return;
-
-    memset(&rule, 0, sizeof rule);
-    for (i = fireWallBaseNum; i < fireWallBaseNum + fireWallNumNums; i++) {
-        rule.fw_number = i;
-        while (!setsockopt(fireWallFD, IPPROTO_IP, IP_FW_DEL, &rule, sizeof rule))
-            ;
-    }
-    memset(fireWallField, 0, fireWallNumNums);
-}
-#endif
diff --git a/usr.sbin/ppp/libalias/alias_ftp.c b/usr.sbin/ppp/libalias/alias_ftp.c
deleted file mode 100644
index df6d02c1d3d..00000000000
--- a/usr.sbin/ppp/libalias/alias_ftp.c
+++ /dev/null
@@ -1,225 +0,0 @@
-/*
-    Alias_ftp.c performs special processing for FTP sessions under
-    TCP.  Specifically, when a PORT command from the client side
-    is sent, it is intercepted and modified.  The address is changed
-    to the gateway machine and an aliasing port is used.
-
-    For this routine to work, the PORT command must fit entirely
-    into a single TCP packet.  This is typically the case, but exceptions
-    can easily be envisioned under the actual specifications.
-
-    Probably the most troubling aspect of the approach taken here is
-    that the new PORT command will typically be a different length, and
-    this causes a certain amount of bookkeeping to keep track of the
-    changes of sequence and acknowledgment numbers, since the client
-    machine is totally unaware of the modification to the TCP stream.
-
-
-    This software is placed into the public domain with no restrictions
-    on its distribution.
-
-    Initial version:  August, 1996  (cjm)
-
-    Version 1.6
-         Brian Somers and Martin Renters identified an IP checksum
-         error for modified IP packets.
-
-    Version 1.7:  January 9, 1996 (cjm)
-         Differental checksum computation for change
-         in IP packet length.
-   
-    Version 2.1:  May, 1997 (cjm)
-         Very minor changes to conform with
-         local/global/function naming conventions
-         withing the packet alising module.
-
-    See HISTORY file for record of revisions.
-*/
-
-/* Includes */
-#include <ctype.h>
-#include <stdio.h> 
-#include <string.h>
-#include <sys/types.h>
-#include <netinet/in_systm.h>
-#include <netinet/in.h>
-#include <netinet/ip.h>
-#include <netinet/tcp.h>
-
-#include "alias_local.h"
-
-static void NewFtpPortCommand(struct ip *, struct alias_link *, struct in_addr, u_short, int);
-
-
-
-void
-AliasHandleFtpOut(
-struct ip *pip,	  /* IP packet to examine/patch */
-struct alias_link *link, /* The link to go through (aliased port) */
-int maxpacketsize  /* The maximum size this packet can grow to (including headers) */)
-{
-    int hlen, tlen, dlen;
-    struct in_addr true_addr;
-    u_short true_port;
-    char *sptr;
-    struct tcphdr *tc;
-        
-/* Calculate data length of TCP packet */
-    tc = (struct tcphdr *) ((char *) pip + (pip->ip_hl << 2));
-    hlen = (pip->ip_hl + tc->th_off) << 2;
-    tlen = ntohs(pip->ip_len);
-    dlen = tlen - hlen;
-
-/* Return is data length is too long or too short */
-    if (dlen<10 || dlen>80)
-        return;
-
-/* Place string pointer and beginning of data */
-    sptr = (char *) pip;  
-    sptr += hlen;
-
-/* Parse through string using state diagram method */
-    {
-        char ch, zero;
-        int i, state;
-        u_long a1, a2, a3, a4;
-        u_short p1, p2; 
-
-        a1=0; a2=0; a3=0; a4=0; p1=0; p2=0;
-        zero = '0';
-        state=-4;
-        for (i=0; i<dlen; i++)
-        {
-            ch = sptr[i];
-            switch (state)
-            {
-                case -4: if (ch == 'P') state=-3; else return; break;
-                case -3: if (ch == 'O') state=-2; else return; break;
-                case -2: if (ch == 'R') state=-1; else return; break;
-                case -1: if (ch == 'T') state= 0; else return; break;
-
-                case 0 :
-                    if (isdigit(ch)) {a1=ch-zero; state=1 ;} break;
-                case 1 :
-                    if (isdigit(ch)) a1=10*a1+ch-zero; else state=2 ; break;
-                case 2 :
-                    if (isdigit(ch)) {a2=ch-zero; state=3 ;} break;
-                case 3 :
-                    if (isdigit(ch)) a2=10*a2+ch-zero; else state=4 ; break;
-                case 4 :
-                    if (isdigit(ch)) {a3=ch-zero; state=5 ;} break;
-                case 5 :
-                    if (isdigit(ch)) a3=10*a3+ch-zero; else state=6 ; break;
-                case 6 :
-                    if (isdigit(ch)) {a4=ch-zero; state=7 ;} break;
-                case 7 :
-                    if (isdigit(ch)) a4=10*a4+ch-zero; else state=8 ; break;
-                case 8 :
-                    if (isdigit(ch)) {p1=ch-zero; state=9 ;} break;
-                case 9 :
-                    if (isdigit(ch)) p1=10*p1+ch-zero; else state=10; break;
-                case 10:
-                    if (isdigit(ch)) {p2=ch-zero; state=11;} break;
-                case 11:
-                    if (isdigit(ch)) p2=10*p2+ch-zero; break;
-            }
-        }
-
-        if (state == 11)
-        {
-            true_port = htons((p1<<8) + p2);
-            true_addr.s_addr = htonl((a1<<24) + (a2<<16) +(a3<<8) + a4);
-            NewFtpPortCommand(pip, link, true_addr, true_port, maxpacketsize);
-        }
-    }
-}
-
-static void
-NewFtpPortCommand(struct ip *pip,
-                  struct alias_link *link,
-                  struct in_addr true_addr,
-                  u_short true_port,
-                  int maxpacketsize)
-{ 
-    struct alias_link *ftp_link;
-
-/* Establish link to address and port found in PORT command */
-    ftp_link = FindUdpTcpOut(true_addr, GetDestAddress(link),
-                             true_port, 0, IPPROTO_TCP);
-
-    if (ftp_link != NULL)
-    {
-        int slen, hlen, tlen, dlen;
-        struct tcphdr *tc;
-
-/* Punch hole in firewall */
-        PunchFWHole(ftp_link);
-
-/* Calculate data length of TCP packet */
-        tc = (struct tcphdr *) ((char *) pip + (pip->ip_hl << 2));
-        hlen = (pip->ip_hl + tc->th_off) << 2;
-        tlen = ntohs(pip->ip_len);
-        dlen = tlen - hlen;
-
-/* Create new PORT command */
-        {
-            char stemp[80];
-            char *sptr;
-            u_short alias_port;
-            u_char *ptr;
-            int a1, a2, a3, a4, p1, p2; 
-            struct in_addr alias_address;
-        
-/* Decompose alias address into quad format */
-            alias_address = GetAliasAddress(link);
-            ptr = (u_char *) &alias_address.s_addr;
-            a1 = *ptr++; a2=*ptr++; a3=*ptr++; a4=*ptr;
-
-/* Decompose alias port into pair format */
-            alias_port = GetAliasPort(ftp_link);
-            ptr = (char *) &alias_port;
-            p1 = *ptr++; p2=*ptr;
-
-/* Generate command string */
-            sprintf(stemp, "PORT %d,%d,%d,%d,%d,%d\r\n",
-                     a1,a2,a3,a4,p1,p2);
-
-/* Save string length for IP header modification */
-            slen = strlen(stemp);
-
-/* Copy into IP packet */
-            sptr = (char *) pip; sptr += hlen;
-            strncpy(sptr, stemp, maxpacketsize-hlen);
-        }
-
-/* Save information regarding modified seq and ack numbers */
-        {
-            int delta;
-
-            SetAckModified(link);
-            delta = GetDeltaSeqOut(pip, link);
-            AddSeq(pip, link, delta+slen-dlen);
-        }
-
-/* Revise IP header */
-        {
-            u_short new_len;
-
-            new_len = htons(hlen + slen);
-            DifferentialChecksum(&pip->ip_sum,
-                                 &new_len,
-                                 &pip->ip_len,
-                                 1);
-            pip->ip_len = new_len;
-        }
-
-/* Compute TCP checksum for revised packet */
-        tc->th_sum = 0;
-        tc->th_sum = TcpChecksum(pip);
-    }
-    else
-    {
-        fprintf(stderr,
-        "PacketAlias/HandleFtpOut: Cannot allocate FTP data port\n");
-    }
-}
diff --git a/usr.sbin/ppp/libalias/alias_irc.c b/usr.sbin/ppp/libalias/alias_irc.c
deleted file mode 100644
index 73a02e5e584..00000000000
--- a/usr.sbin/ppp/libalias/alias_irc.c
+++ /dev/null
@@ -1,314 +0,0 @@
-/* Alias_irc.c intercepts packages contain IRC CTCP commands, and
-	changes DCC commands to export a port on the aliasing host instead
-	of an aliased host.
-
-    For this routine to work, the DCC command must fit entirely into a
-    single TCP packet.  This will usually happen, but is not
-    guaranteed.
-
-	 The interception is likely to change the length of the packet.
-	 The handling of this is copied more-or-less verbatim from
-	 ftp_alias.c
-
-    This software is placed into the public domain with no restrictions
-    on its distribution.
-
-	 Initial version: Eivind Eklund <perhaps@yes.no> (ee) 97-01-29
-
-         Version 2.1:  May, 1997 (cjm)
-             Very minor changes to conform with
-             local/global/function naming conventions
-             withing the packet alising module.
-*/
-
-/* Includes */
-#include <ctype.h>
-#include <stdio.h> 
-#include <string.h>
-#include <sys/types.h>
-#include <netinet/in_systm.h>
-#include <netinet/in.h>
-#include <netinet/ip.h>
-#include <netinet/tcp.h>
-#include <limits.h>
-
-#include "alias_local.h"
-
-/* Local defines */
-#define DBprintf(a)
-
-
-void
-AliasHandleIrcOut(struct ip *pip, /* IP packet to examine */
-				 struct alias_link *link,		  /* Which link are we on? */
-				 int maxsize		  /* Maximum size of IP packet including headers */
-				 )
-{       
-    int hlen, tlen, dlen;
-    struct in_addr true_addr;
-    u_short true_port;
-    char *sptr;
-    struct tcphdr *tc;
-	 int i;							  /* Iterator through the source */
-        
-/* Calculate data length of TCP packet */
-    tc = (struct tcphdr *) ((char *) pip + (pip->ip_hl << 2));
-    hlen = (pip->ip_hl + tc->th_off) << 2;
-    tlen = ntohs(pip->ip_len);
-    dlen = tlen - hlen;
-
-	 /* Return if data length is too short - assume an entire PRIVMSG in each packet. */
-    if (dlen<sizeof(":A!a@n.n PRIVMSG A :aDCC 1 1a")-1)
-        return;
-
-/* Place string pointer at beginning of data */
-    sptr = (char *) pip;  
-    sptr += hlen;
-	 maxsize -= hlen;				  /* We're interested in maximum size of data, not packet */
-
-	 /* Search for a CTCP command [Note 1] */
-	 for(	i=0; i<dlen; i++ ) {
-		 if(sptr[i]=='\001')
-			 goto lFOUND_CTCP;
-	 }
-	 return;					  /* No CTCP commands in  */
-	 /* Handle CTCP commands - the buffer may have to be copied */
-lFOUND_CTCP:
-	 {
-		 char newpacket[65536];	  /* Estimate of maximum packet size :) */
-		 int  copyat = i;			  /* Same */
-		 int  iCopy = 0;			  /* How much data have we written to copy-back string? */
-		 unsigned long org_addr;  /* Original IP address */
-		 unsigned short org_port; /* Original source port address */
-	 lCTCP_START:
-		 if( i >= dlen || iCopy >= sizeof(newpacket) )
-			 goto lPACKET_DONE;
-		 newpacket[iCopy++] = sptr[i++];	/* Copy the CTCP start character */
-		 /* Start of a CTCP */
-		 if( i+4 >= dlen )		  /* Too short for DCC */
-			 goto lBAD_CTCP;
-		 if( sptr[i+0] != 'D' )
-			 goto lBAD_CTCP;
-		 if( sptr[i+1] != 'C' )
-			 goto lBAD_CTCP;
-		 if( sptr[i+2] != 'C' )
-			 goto lBAD_CTCP;
-		 if( sptr[i+3] != ' ' )
-			 goto lBAD_CTCP;
-		 /* We have a DCC command - handle it! */
-		 i+= 4;						  /* Skip "DCC " */
-		 if( iCopy+4 > sizeof(newpacket) )
-			 goto lPACKET_DONE;
-		 newpacket[iCopy++] = 'D';
-		 newpacket[iCopy++] = 'C';
-		 newpacket[iCopy++] = 'C';
-		 newpacket[iCopy++] = ' ';
-
-		 DBprintf(("Found DCC\n"));
-		 /* Skip any extra spaces (should not occur according to
-          protocol, but DCC breaks CTCP protocol anyway */
-		 while(sptr[i] == ' ') {
-			 if( ++i >= dlen) {
-				 DBprintf(("DCC packet terminated in just spaces\n"));
-				 goto lPACKET_DONE;
-			 }
-		 }
-
-		 DBprintf(("Transferring command...\n"));
-		 while(sptr[i] != ' ') {
-			 newpacket[iCopy++] = sptr[i];
-			 if( ++i >= dlen || iCopy >= sizeof(newpacket) ) {
-				 DBprintf(("DCC packet terminated during command\n"));
-				 goto lPACKET_DONE;
-			 }
-		 }
-		 /* Copy _one_ space */
-		 if( i+1 < dlen && iCopy < sizeof(newpacket) )
-			 newpacket[iCopy++] = sptr[i++];
-
-		 DBprintf(("Done command - removing spaces\n"));
-		 /* Skip any extra spaces (should not occur according to
-          protocol, but DCC breaks CTCP protocol anyway */
-		 while(sptr[i] == ' ') {
-			 if( ++i >= dlen ) {
-				 DBprintf(("DCC packet terminated in just spaces (post-command)\n"));
-				 goto lPACKET_DONE;
-			 }
-		 }
-
-		 DBprintf(("Transferring filename...\n"));
-		 while(sptr[i] != ' ') {
-			 newpacket[iCopy++] = sptr[i];
-			 if( ++i >= dlen || iCopy >= sizeof(newpacket) ) {
-				 DBprintf(("DCC packet terminated during filename\n"));
-				 goto lPACKET_DONE;
-			 }
-		 }
-		 /* Copy _one_ space */
-		 if( i+1 < dlen && iCopy < sizeof(newpacket) )
-			 newpacket[iCopy++] = sptr[i++];
-
-		 DBprintf(("Done filename - removing spaces\n"));
-		 /* Skip any extra spaces (should not occur according to
-          protocol, but DCC breaks CTCP protocol anyway */
-		 while(sptr[i] == ' ') {
-			 if( ++i >= dlen ) {
-				 DBprintf(("DCC packet terminated in just spaces (post-filename)\n"));
-				 goto lPACKET_DONE;
-			 }
-		 }
-
-		 DBprintf(("Fetching IP address\n"));
-		 /* Fetch IP address */
-		 org_addr = 0;
-		 while(i<dlen && isdigit(sptr[i])) {
-			 if( org_addr > ULONG_MAX/10UL )	{ /* Terminate on overflow */
-				 DBprintf(("DCC Address overflow (org_addr == 0x%08lx, next char %c\n", org_addr, sptr[i]));
-				 goto lBAD_CTCP;
-			 }
-			 org_addr *= 10;
-			 org_addr += sptr[i++]-'0';
-		 }
-		 DBprintf(("Skipping space\n"));
-		 if( i+1 >= dlen || sptr[i] != ' ' ) {
-			 DBprintf(("Overflow (%d >= %d) or bad character (%02x) terminating IP address\n", i+1, dlen, sptr[i]));
-			 goto lBAD_CTCP;
-		 }
-		 /* Skip any extra spaces (should not occur according to
-          protocol, but DCC breaks CTCP protocol anyway, so we might
-          as well play it safe */
-		 while(sptr[i] == ' ') {
-			 if( ++i >= dlen ) {
-				 DBprintf(("Packet failure - space overflow.\n"));
-				 goto lPACKET_DONE;
-			 }
-		 }
-		 DBprintf(("Fetching port number\n"));
-		 /* Fetch source port */
-		 org_port = 0;
-		 while(i<dlen && isdigit(sptr[i])) {
-			 if( org_port > 6554 )	{ /* Terminate on overflow (65536/10 rounded up*/
-				 DBprintf(("DCC: port number overflow\n"));
-				 goto lBAD_CTCP;
-			 }
-			 org_port *= 10;
-			 org_port += sptr[i++]-'0';
-		 }
-		 /* Skip illegal addresses (or early termination) */
-		 if( i >= dlen || (sptr[i] != '\001' && sptr[i] != ' ') ) {
-			 DBprintf(("Bad port termination\n"));
-			 goto lBAD_CTCP;
-		 }
-		 DBprintf(("Got IP %lu and port %u\n", org_addr, (unsigned)org_port));
-
-		 /* We've got the address and port - now alias it */
-		 {
-			 struct alias_link *dcc_link;
-			 struct in_addr destaddr;
-			 
-
-			 true_port = htons(org_port);
-			 true_addr.s_addr = htonl(org_addr);
-			 destaddr.s_addr = 0;
-
-			 /* Steal the FTP_DATA_PORT - it doesn't really matter, and this
-				 would probably allow it through at least _some_
-				 firewalls. */
-			 dcc_link = FindUdpTcpOut (true_addr,
-											destaddr,
-										   true_port,
-											0, IPPROTO_TCP);
-			 DBprintf(("Got a DCC link\n"));
-			 if ( dcc_link ) {
-				 struct in_addr alias_address;	/* Address from aliasing */
-				 u_short alias_port;	/* Port given by aliasing */
-
-				 /* Generate firewall hole as appropriate */
-				 PunchFWHole(dcc_link);
-
-				 alias_address = GetAliasAddress(link);
-				 iCopy += snprintf(&newpacket[iCopy],
-										 sizeof(newpacket)-iCopy, 
-										 "%lu ", (u_long)htonl(alias_address.s_addr));
-				 if( iCopy >= sizeof(newpacket) ) { /* Truncated/fit exactly - bad news */
-					 DBprintf(("DCC constructed packet overflow.\n"));
-					 goto lBAD_CTCP;
-				 }
-				 alias_port = GetAliasPort(dcc_link);
-				 iCopy += snprintf(&newpacket[iCopy],
-										 sizeof(newpacket)-iCopy, 
-										 "%u", htons(alias_port) );
-				 /* Done - truncated cases will be taken care of by lBAD_CTCP */
-				 DBprintf(("Aliased IP %lu and port %u\n", alias_address.s_addr, (unsigned)alias_port));
-			 }
-		 }
-		 /* An uninteresting CTCP - state entered right after '\001' has
-          been pushed.  Also used to copy the rest of a DCC, after IP
-          address and port has been handled */
-	 lBAD_CTCP:
-		 for(; i<dlen && iCopy<sizeof(newpacket); i++,iCopy++) {
-			 newpacket[iCopy] = sptr[i]; /* Copy CTCP unchanged */
-			 if(sptr[i] == '\001') {
-				 goto lNORMAL_TEXT;
-			 }
-		 }
-		 goto lPACKET_DONE;
-		 /* Normal text */
-	 lNORMAL_TEXT:
-		 for(; i<dlen && iCopy<sizeof(newpacket); i++,iCopy++) {
-			 newpacket[iCopy] = sptr[i]; /* Copy CTCP unchanged */
-			 if(sptr[i] == '\001') {
-				 goto lCTCP_START;
-			 }
-		 }
-		 /* Handle the end of a packet */
-	 lPACKET_DONE:
-		 iCopy = iCopy > maxsize-copyat ? maxsize-copyat : iCopy;
-		 memcpy(sptr+copyat, newpacket, iCopy);
-
-/* Save information regarding modified seq and ack numbers */
-        {
-            int delta;
-
-            SetAckModified(link);
-            delta = GetDeltaSeqOut(pip, link);
-            AddSeq(pip, link, delta+copyat+iCopy-dlen);
-        }
-
-		  /* Revise IP header */
-        {
-			  u_short new_len;
-			  
-			  new_len = htons(hlen + iCopy + copyat);
-			  DifferentialChecksum(&pip->ip_sum,
-										  &new_len,
-										  &pip->ip_len,
-										  1);
-			  pip->ip_len = new_len;
-        }
-
-		  /* Compute TCP checksum for revised packet */
-        tc->th_sum = 0;
-        tc->th_sum = TcpChecksum(pip);
-		  return;
-	 }
-}
-
-/* Notes:
-	[Note 1]
-	The initial search will most often fail; it could be replaced with a 32-bit specific search.
-	Such a search would be done for 32-bit unsigned value V:
-	V ^= 0x01010101;				  (Search is for null bytes)
-	if( ((V-0x01010101)^V) & 0x80808080 ) {
-     (found a null bytes which was a 01 byte)
-	}
-   To assert that the processor is 32-bits, do
-   extern int ircdccar[32];        (32 bits)
-   extern int ircdccar[CHAR_BIT*sizeof(unsigned int)];
-   which will generate a type-error on all but 32-bit machines.
-
-	[Note 2] This routine really ought to be replaced with one that
-	creates a transparent proxy on the aliasing host, to allow arbitary
-	changes in the TCP stream.  This should not be too difficult given
-	this base;  I (ee) will try to do this some time later.
-	*/
diff --git a/usr.sbin/ppp/libalias/alias_local.h b/usr.sbin/ppp/libalias/alias_local.h
deleted file mode 100644
index ba5f31fa94e..00000000000
--- a/usr.sbin/ppp/libalias/alias_local.h
+++ /dev/null
@@ -1,99 +0,0 @@
-/* -*- mode: c; tab-width: 3; c-basic-offset: 3; -*-
-    Alias_local.h contains the function prototypes for alias.c,
-    alias_db.c, alias_util.c and alias_ftp.c, alias_irc.c (as well
-    as any future add-ons).  It is intended to be used only within
-    the aliasing software.  Outside world interfaces are defined
-    in alias.h
-
-    This software is placed into the public domain with no restrictions
-    on its distribution.
-
-    Initial version:  August, 1996  (cjm)    
-    
-     <updated several times by original author and Eivind Eiklund>
-*/
-#ifndef ALIAS_LOCAL_H
-#define ALIAS_LOCAL_H
-
-extern int packetAliasMode;
-
-struct alias_link;
-
-/* General utilities */
-u_short IpChecksum(struct ip *);
-u_short TcpChecksum(struct ip *);
-void DifferentialChecksum(u_short *, u_short *, u_short *, int);
-
-/* Internal data access */
-struct alias_link *
-FindIcmpIn(struct in_addr, struct in_addr, u_short);
-
-struct alias_link *
-FindIcmpOut(struct in_addr, struct in_addr, u_short);
-
-struct alias_link *
-FindFragmentIn1(struct in_addr, struct in_addr, u_short);
-
-struct alias_link *
-FindFragmentIn2(struct in_addr, struct in_addr, u_short);
-
-struct alias_link *
-AddFragmentPtrLink(struct in_addr, u_short);
-
-struct alias_link *
-FindFragmentPtr(struct in_addr, u_short);
-
-struct alias_link *
-FindUdpTcpIn (struct in_addr, struct in_addr, u_short, u_short, u_char);
-
-struct alias_link *
-FindUdpTcpOut(struct in_addr, struct in_addr, u_short, u_short, u_char);
-
-struct in_addr
-FindOriginalAddress(struct in_addr);
-
-struct in_addr
-FindAliasAddress(struct in_addr);
-
-/* External data access/modification */
-void GetFragmentAddr(struct alias_link *, struct in_addr *);
-void SetFragmentAddr(struct alias_link *, struct in_addr);
-void GetFragmentPtr(struct alias_link *, char **);
-void SetFragmentPtr(struct alias_link *, char *);
-void SetStateIn(struct alias_link *, int);
-void SetStateOut(struct alias_link *, int);
-int GetStateIn(struct alias_link *);
-int GetStateOut(struct alias_link *);
-struct in_addr GetOriginalAddress(struct alias_link *);
-struct in_addr GetDestAddress(struct alias_link *);
-struct in_addr GetAliasAddress(struct alias_link *);
-struct in_addr GetDefaultAliasAddress(void);
-void SetDefaultAliasAddress(struct in_addr);
-u_short GetOriginalPort(struct alias_link *);
-u_short GetAliasPort(struct alias_link *);
-void SetAckModified(struct alias_link *);
-int GetAckModified(struct alias_link *);
-int GetDeltaAckIn(struct ip *, struct alias_link *);
-int GetDeltaSeqOut(struct ip *, struct alias_link *);
-void AddSeq(struct ip *, struct alias_link *, int);
-void SetExpire(struct alias_link *, int);
-void ClearCheckNewLink(void);
-void PunchFWHole(struct alias_link *);
-
-
-/* Housekeeping function */
-void HouseKeeping(void);
-
-/* Tcp specfic routines */
-/*lint -save -library Suppress flexelint warnings */
-void AliasHandleFtpOut(struct ip *, struct alias_link *, int);
-void AliasHandleIrcOut(struct ip *pip, struct alias_link *link, int maxsize );
-
-enum alias_tcp_state {
-    ALIAS_TCP_STATE_NOT_CONNECTED,
-    ALIAS_TCP_STATE_CONNECTED,
-    ALIAS_TCP_STATE_DISCONNECTED
-};
-
-/*lint -restore */
-#endif /* defined(ALIAS_LOCAL_H) */
diff --git a/usr.sbin/ppp/libalias/alias_old.c b/usr.sbin/ppp/libalias/alias_old.c
deleted file mode 100644
index 3f634d44841..00000000000
--- a/usr.sbin/ppp/libalias/alias_old.c
+++ /dev/null
@@ -1,77 +0,0 @@
-/*
-    This file can be considered a junk pile of old functions that
-    are either obsolete or have had their names changed.  In the
-    transition from alias2.1 to alias2.2, all the function names
-    were rationalized so that they began with "PacketAlias..."
-
-    These functions are included for backwards compatibility.  
-*/
-
-#include <sys/types.h>
-#include <netinet/in_systm.h>
-#include <netinet/in.h>
-#include <netinet/ip.h>
-#include "alias.h"
-#include "alias_local.h"
-
-void
-InitPacketAlias(void)
-{
-    PacketAliasInit();
-}
-
-void
-SetPacketAliasAddress(struct in_addr addr)
-{
-    PacketAliasSetAddress(addr);
-}
-
-unsigned int
-SetPacketAliasMode(unsigned int flags, unsigned int mask)
-{
-    return PacketAliasSetMode(flags, mask);
-}
-
-int
-PacketAliasPermanentLink(struct in_addr src_addr,   u_short src_port,
-                         struct in_addr dst_addr,   u_short dst_port,
-                         u_short alias_port, u_char proto)
-{
-    struct alias_link *link;
-    struct in_addr null_address;
-
-    null_address.s_addr = 0;
-    link = PacketAliasRedirectPort(src_addr, src_port,
-                                       dst_addr, dst_port,
-                                       null_address, alias_port,
-                                       proto);
-
-    if (link == NULL)
-        return -1;
-    else
-        return 0;
-}
-
-int
-SaveFragmentPtr(char *ptr)
-{
-    return PacketAliasSaveFragment(ptr);
-}
-
-char *
-GetNextFragmentPtr(char *ptr)
-{
-    return PacketAliasGetFragment(ptr);
-}
-
-void
-FragmentAliasIn(char *header, char *fragment)
-{
-    PacketAliasFragmentIn(header, fragment);
-}
-
-u_short
-InternetChecksum(u_short *ptr, int len)
-{
-    return PacketAliasInternetChecksum(ptr, len);
-}
diff --git a/usr.sbin/ppp/libalias/alias_util.c b/usr.sbin/ppp/libalias/alias_util.c
deleted file mode 100644
index fe076531201..00000000000
--- a/usr.sbin/ppp/libalias/alias_util.c
+++ /dev/null
@@ -1,137 +0,0 @@
-/*
-    Alias_util.h contains general utilities used by other functions
-    in the packet aliasing module.  At the moment, there are functions
-    for computing IP header and TCP packet checksums.
-
-    The checksum routines are based upon example code in a Unix networking
-    text written by Stevens (sorry, I can't remember the title -- but
-    at least this is a good author).
-
-    Initial Version:  August, 1996  (cjm)
-
-    Version 1.7:  January 9, 1997
-         Added differential checksum update function.
-*/
-
-/*
-Note: the checksum routines assume that the actual checksum word has
-been zeroed out.  If the checksum workd is filled with the proper value,
-then these routines will give a result of zero (useful for testing
-purposes);
-*/
-    
-#include <sys/types.h>
-#include <netinet/in_systm.h>
-#include <netinet/in.h>
-#include <netinet/ip.h>
-#include <netinet/tcp.h>
-
-#include "alias.h"
-#include "alias_local.h"
-
-u_short
-PacketAliasInternetChecksum(u_short *ptr, int nbytes)
-{
-    int sum, oddbyte;
-
-    sum = 0;
-    while (nbytes > 1)
-    {
-        sum += *ptr++;
-        nbytes -= 2;
-    }
-    if (nbytes == 1)
-    {
-        oddbyte = 0;
-        *((u_char *) &oddbyte) = *(u_char *) ptr;
-        sum += oddbyte;
-    }
-    sum = (sum >> 16) + (sum & 0xffff);
-    sum += (sum >> 16);
-    return(~sum);
-}
-
-u_short
-IpChecksum(struct ip *pip)
-{
-    return( PacketAliasInternetChecksum((u_short *) pip,
-            (pip->ip_hl << 2)) );
-
-}
-
-u_short 
-TcpChecksum(struct ip *pip)
-{
-    u_short *ptr;
-    struct tcphdr *tc;
-    int nhdr, ntcp, nbytes;
-    int sum, oddbyte;
-
-    nhdr = pip->ip_hl << 2;
-    ntcp = ntohs(pip->ip_len) - nhdr;
-
-    tc = (struct tcphdr *) ((char *) pip + nhdr);
-    ptr = (u_short *) tc;
-    
-/* Add up TCP header and data */
-    nbytes = ntcp;
-    sum = 0;
-    while (nbytes > 1)
-    {
-        sum += *ptr++;
-        nbytes -= 2;
-    }
-    if (nbytes == 1)
-    {
-        oddbyte = 0;
-        *((u_char *) &oddbyte) = *(u_char *) ptr;
-        sum += oddbyte;
-    }
-
-/* "Pseudo-header" data */
-    ptr = (u_short *) &(pip->ip_dst);
-    sum += *ptr++;
-    sum += *ptr;
-    ptr = (u_short *) &(pip->ip_src);
-    sum += *ptr++;
-    sum += *ptr;
-    sum += htons((u_short) ntcp);
-    sum += htons((u_short) pip->ip_p);
-
-/* Roll over carry bits */
-    sum = (sum >> 16) + (sum & 0xffff);
-    sum += (sum >> 16);
-
-/* Return checksum */
-    return((u_short) ~sum);
-}
-
-
-void
-DifferentialChecksum(u_short *cksum, u_short *new, u_short *old, int n)
-{
-    int i;
-    int accumulate;
-
-    accumulate = *cksum;
-    for (i=0; i<n; i++)
-    {
-        accumulate -= *new++;
-        accumulate += *old++;
-    }
-
-    if (accumulate < 0)
-    {
-        accumulate = -accumulate;
-        accumulate = (accumulate >> 16) + (accumulate & 0xffff);
-        accumulate += accumulate >> 16;
-        *cksum = (u_short) ~accumulate;
-    }
-    else
-    {
-        accumulate = (accumulate >> 16) + (accumulate & 0xffff);
-        accumulate += accumulate >> 16;
-        *cksum = (u_short) accumulate;
-    }
-}
-
diff --git a/usr.sbin/ppp/libalias/libalias.3 b/usr.sbin/ppp/libalias/libalias.3
deleted file mode 100644
index 37e17860632..00000000000
--- a/usr.sbin/ppp/libalias/libalias.3
+++ /dev/null
@@ -1,768 +0,0 @@
-.Dd July, 1997
-.Dt "libalias" 3 
-.Os 
-.Sh NAME
-.Nm "libalias"
-Packet Aliasing Library.  A collection of
-functions for aliasing and de-aliasing
-of IP packets, intended for masquerading and
-network address translation (NAT).  
-
-.Sh SYNOPSIS
-.Fd #include <sys/types.h>
-.Fd #include <netinet/in.h>
-.Fd #include <alias.h>
-
-Function prototypes are given in the main body
-of the text.
-
-.Sh CONTENTS
-.Bd -literal -offset left
-1. Introduction
-2. Initialization and Control
-    2.1 PacketAliasInit()
-    2.2 PacketAliasUninit()
-    2.3 PacketAliasSetAddress()
-    2.4 PacketAliasSetMode()
-    2.5 PacketAliasSetFWBase()
-3. Packet Handling
-    3.1 PacketAliasOut()
-    3.2 PacketAliasIn()
-4. Port and Address Redirection
-    4.1 PacketAliasRedirectPort()
-    4.2 PacketAliasRedirectAddr()
-    4.3 PacketAliasRedirectDelete()
-5. Fragment Handling
-    5.1 PacketAliasSaveFragment()
-    5.2 PacketAliasGetFragment()
-    5.3 PacketAliasFragmentIn()
-6. Miscellaneous Functions
-    6.1 PacketAliasSetTarget()
-    6.2 PacketAliasCheckNewLink()
-    6.3 PacketAliasInternetChecksum()
-7. Authors
-8. Acknowledgments
-
-Appendix A: Conceptual Background
-    A.1 Aliasing Links
-    A.2 Static and Dynamic Links
-    A.3 Partially Specified Links
-    A.4 Dynamic Link Creation
-.Ed
-
-.Sh 1. Introduction
-This library is a moderately portable
-set of functions designed to assist
-in the process of IP masquerading and
-network address translation.  Outgoing
-packets from a local network with
-unregistered IP addresses can be aliased
-to appear as if they came from an
-accessible IP address.  Incoming packets
-are then de-aliased so that they are sent
-to the correct machine on the local network.
-
-A certain amount of flexibility is built
-into the packet aliasing engine.  In
-the simplest mode of operation, a
-many-to-one address mapping takes place
-between local network and the packet
-aliasing host.  This is known as IP
-masquerading.  In addition, one-to-one
-mappings between local and public addresses
-can also be implemented, which is known as
-static NAT.  In between these extremes,
-different groups of private addresses
-can be linked to different public addresses,
-comprising several distinct many-to-one
-mappings.  Also, a given public address
-and port can be staticly redirected to
-a private address/port.
-
-The packet aliasing engine was designed
-to operate in user space outside of the
-kernel, without any access to private
-kernel data structure, but the source code
-can also be ported to a kernel environment.
-
-.Sh 2. Initialization and Control
-Two specific functions, PacketAliasInit()
-and PacketAliasSetAddress(), must always be
-called before any packet handling may be
-performed.  In addition, the operating mode
-of the packet aliasing engine can be customized
-by calling PacketAliasSetMode().
-.Ss 2.1 PacketAliasInit()
-
-.Ft void
-.Fn PacketAliasInit "void"
-
-This function has no argument or return
-value and is used to initialize internal
-data structures. The following mode bits
-are always set after calling
-PacketAliasInit().  See section 2.3 for
-the meaning of these mode bits. 
-.Bd -literal -offset indent
-    PKT_ALIAS_USE_SAME_PORTS
-    PKT_ALIAS_USE_SOCKETS
-    PKT_ALIAS_RESET_ON_ADDR_CHANGE
-
-.Ed
-This function will always return the packet
-aliasing engine to the same initial state.
-PacketAliasSetAddress() must be called afterwards,
-and any desired changes from the default mode
-bits listed above require a call to
-PacketAliasSetMode().
-
-It is mandatory that this function be called
-at the beginning of a program prior to any
-packet handling.
-.Ss 2.2 PacketAliasUninit()
-
-.Ft void
-.Fn PacketAliasUninit "void"
-
-This function has no argument or return
-value and is used to clear any resources
-attached to internal data structures.
-
-This functions should be called when a
-program stop using the aliasing engine;
-it do, among other things, clear out any
-firewall holes.  To provide backwards
-compatibility and extra security, it is
-added to the atexit() chain by
-PacketAliasInit().  Calling it multiple
-times is harmless.
-.Ss 2.3 PacketAliasSetAddress()
-
-.Ft void
-.Fn PacketAliasSetAddress "struct in_addr addr"
-
-This function sets the source address to which
-outgoing packets from the local area network
-are aliased.  All outgoing packets are remapped
-to this address unless overridden by a static
-address mapping established by
-PacketAliasRedirectAddr().
-
-If the PKT_ALIAS_RESET_ON_ADDR_CHANGE mode bit
-is set (the default mode of operation), then
-the internal aliasing link tables will be reset
-any time the aliasing address changes, as if
-PacketAliasReset() were called.  This is useful
-for interfaces such as ppp where the IP
-address may or may not change on successive
-dial-up attempts.
-
-If the PKT_ALIAS_RESET_ON_ADDR_CHANGE mode bit
-is set to zero, this function can also be used to
-dynamically change the aliasing address on a
-packet to packet basis (it is a low overhead
-call).  
-
-It is mandatory that this function be called
-prior to any packet handling.
-.Ss 2.4 PacketAliasSetMode()
-
-.Ft unsigned int
-.Fn PacketAliasSetMode "unsigned int mode" "unsigned int mask"
-
-This function sets or clears mode bits
-according to the value of
-.Em mode .
-Only bits marked in
-.Em mask
-are affected.  The following mode bits are
-defined in alias.h:
-.Bl -hang -offset left
-.It PKT_ALIAS_LOG.
-Enables logging /var/log/alias.log.  The log file
-shows total numbers of links (icmp, tcp, udp) each
-time an aliasing link is created or deleted.  Mainly
-useful for debugging when the log file is viewed
-continuously with "tail -f".
-.It PKT_ALIAS_DENY_INCOMING.
-If this mode bit is set, all incoming packets
-associated with new TCP connections or new
-UDP transactions will be marked for being
-ignored (PacketAliasIn() return code
-PKT_ALIAS_IGNORED) by the calling program.
-Response packets to connections or transactions
-initiated from the packet aliasing host or
-local network will be unaffected.  This mode
-bit is useful for implementing a one-way firewall.
-.It PKT_ALIAS_SAME_PORTS.
-If this mode bit is set, the packet aliasing
-engine will attempt to leave the alias port
-numbers unchanged from the actual local port
-number.  This can be done as long as the
-quintuple (proto, alias addr, alias port,
-remote addr, remote port) is unique.  If a
-conflict exists, an new aliasing port number is
-chosen even if this mode bit is set.
-.It PKT_ALIAS_USE_SOCKETS.
-This bit should be set when the the packet
-aliasing host originates network traffic as
-well as forwards it.  When the packet aliasing
-host is waiting for a connection from an
-unknown host address or unknown port number
-(e.g. an FTP data connection), this mode bit
-specifies that a socket be allocated as a place
-holder to prevent port conflicts.  Once a
-connection is extablished, usually within a
-minute or so, the socket is closed.
-.It PKT_ALIAS_UNREGISTERED_ONLY.
-If this mode bit is set, traffic on the
-local network which does not originate from
-unregistered address spaces will be ignored.
-Standard Class A, B and C unregistered addresses
-are:
-.Bd -literal -offset indent
-    10.0.0.0     ->   10.255.255.255   (Class A subnet)
-    172.16.0.0   ->   172.31.255.255   (Class B subnets)
-    192.168.0.0  ->   192.168.255.255  (Class C subnets)
-
-.Ed
-This option is useful in the case that
-packet aliasing host has both registered and
-unregistered subnets on different interfaces.
-The registered subnet is fully accessible to
-the outside world, so traffic from it doesn't 
-need to be passed through the packet aliasing
-engine.
-.It PKT_ALIAS_RESET_ON_ADDR_CHANGE.
-When this mode bit is set and
-PacketAliasSetAddress() is called to change
-the aliasing address, the internal link table
-of the packet aliasing engine will be cleared.
-This operating mode is useful for ppp links
-where the interface address can sometimes
-change or remain the same between dial-ups.
-If this mode bit is not set, it the link table
-will never be reset in the event of an
-address change.
-.It PKT_ALIAS_PUNCH_FW.
-This option make libalias `punch holes' in an
-ipfw based firewall for FTP/IRC DCC connections.
-The holes punched are bound by from/to IP address
-and port; it will not be possible to use a hole
-for another connection.  A hole is removed when
-the connection that use it die.  To cater for
-unexpected death of a program using libalias (e.g
-kill -9), changing the state of the flag will
-clear the entire ipfw range allocated for holes.
-This will also happen on the initial call to
-PacketAliasSetFWBase().  This call must happen
-prior to setting this flag.
-
-.El
-
-.Ss 2.5 PacketAliasSetFWBase()
-
-.Ft void
-.Fn PacketAliasSetFWBase "unsigned int base" "unsigned int num"
-
-Set IPFW range allocated for punching firewall holes (with the
-PKT_ALIAS_PUNCH_FW flag).  The range will be cleared for all rules on
-initialization.
-
-.Sh 3. Packet Handling
-The packet handling functions are used to 
-modify incoming (remote->local) and outgoing
-(local->remote) packets.  The calling program
-is responsible for receiving and sending
-packets via network interfaces.
-
-Along with PacketAliasInit() and PacketAliasSetAddress(),
-the two packet handling functions, PacketAliasIn()
-and PacketAliasOut(), comprise minimal set of functions
-needed for a basic IP masquerading implementation.
-.Ss 3.1 PacketAliasIn()
-
-.Ft int
-.Fn PacketAliasIn "char *buffer" "int maxpacketsize"
-
-An incoming packet coming from a remote machine to
-the local network is de-aliased by this function.
-The IP packet is pointed to by
-.Em buffer ,
-and
-.Em maxpacketsize
-indicates the size of the data structure containing
-the packet and should be at least as large as the
-actual packet size.
-
-Return codes:
-.Bl -hang -offset left
-.It PKT_ALIAS_ERROR.
-An internal error within the packet aliasing
-engine occured.
-.It PKT_ALIAS_OK.
-The packet aliasing process was successful.
-.It PKT_ALIAS_IGNORED.
-The packet was ignored and not de-aliased.
-This can happen if the protocal is unrecognized,
-possibly an ICMP message type is not handled or
-if incoming packets for new connections are being
-ignored (see PKT_ALIAS_DENY_INCOMING in section
-2.2).
-.It PKT_ALIAS_UNRESOLVED_FRAGMENT.
-This is returned when a fragment cannot be
-resolved because the header fragment has not
-been sent yet.  In this situation, fragments
-must be saved with PacketAliasSaveFragment()
-until a header fragment is found.
-.It PKT_ALIAS_FOUND_HEADER_FRAGMENT.
-The packet aliasing process was successful,
-and a header fragment was found.  This is a
-signal to retrieve any unresolved fragments
-with PacketAliasGetFragment() and de-alias
-them with PacketAliasFragmentIn().
-.El
-.Ss 3.2 PacketAliasOut()
-
-.Ft int
-.Fn PacketAliasIn "char *buffer" "int maxpacketsize"
-
-An outgoing packet coming from the local network
-to a remote machine is aliased by this function.
-The IP packet is pointed to by
-.Em buffer r,
-and
-.Em maxpacketsize
-indicates the maximum packet size permissable
-should the packet length be changed.  IP encoding
-protocols place addresss and port information in
-the encapsulated data stream which have to be
-modified and can account for changes in packet
-length.  Well known examples of such protocols
-are FTP and IRC DCC.
-
-Return codes:
-.Bl -hang -offset left
-.It PKT_ALIAS_ERROR.
-An internal error within the packet aliasing
-engine occured.
-.It PKT_ALIAS_OK.
-The packet aliasing process was successful.
-.It PKT_ALIAS_IGNORED.
-The packet was ignored and not de-aliased.
-This can happen if the protocal is unrecognized,
-or possibly an ICMP message type is not handled.
-.El
-
-.Sh 4. Port and Address Redirection
-The functions described in this section allow machines
-on the local network to be accessible in some degree
-to new incoming connections from the external network.
-Individual ports can be re-mapped or static network
-address translations can be designated.
-.Ss 4.1 PacketAliasRedirectPort()
-
-.Ft struct alias_link *
-.Fo PacketAliasRedirectPort
-.Fa "struct in_addr local_addr"
-.Fa "u_short local_port"
-.Fa "struct in_addr remote_addr"
-.Fa "u_short remote_port"
-.Fa "struct in_addr alias_addr"
-.Fa "u_short alias_port"
-.Fa "u_char proto"
-.Fc
-
-This function specifies that traffic from a
-given remote address/port to an alias address/port
-be redirected to a specified local address/port.
-The paramater
-.Em proto
-can be either IPPROTO_TCP or IPPROTO_UDP, as
-defined in <netinet/in.h>.
-
-If
-.Em local_addr 
-or
-.Em alias_addr
-is zero, this indicates that the packet aliasing
-address as established by PacketAliasSetAddress()
-is to be used.  Even if PacketAliasAddress() is
-called to change the address after PacketAliasRedirectPort()
-is called, a zero reference will track this change.
-
-If 
-.Em remote_addr
-is zero, this indicates to redirect packets from
-any remote address.  Likewise, if
-.Em remote_port
-is zero, this indicates to redirect packets originating
-from any remote port number.  Almost always, the remote
-port specification will be zero, but non-zero remote
-addresses can be sometimes be useful for firewalling. 
-If two calls to PacketAliasRedirectPort() overlap in
-their address/port specifications, then the most recent
-call will have precedence.
-
-This function returns a pointer which can subsequently
-be used by PacketAliasRedirectDelete().  If NULL is
-returned, then the function call did not complete
-successfully.
-
-All port numbers are in network address byte order,
-so it is necessary to use htons() to convert these
-parameters from internally readable numbers to
-network byte order.  Addresses are also in network
-byte order, which is implicit in the use of the
-.Em struct in_addr 
-data type.
-.Ss 4.2 PacketAliasRedirectAddr()
-
-.Ft struct alias_link *
-.Fo PacketAliasRedirectAddr
-.Fa "struct in_addr local_addr"
-.Fa "struct in_addr alias_addr"
-.Fc
-
-This function desgnates that all incoming
-traffic to 
-.Em alias_addr
-be redirected to
-.Em local_addr.
-Similarly, all outgoing traffic from
-.Em local_addr
-is aliased to 
-.Em alias_addr .
-
-If
-.Em local_addr 
-or
-.Em alias_addr
-is zero, this indicates that the packet aliasing
-address as established by PacketAliasSetAddress()
-is to be used.  Even if PacketAliasAddress() is
-called to change the address after PacketAliasRedirectAddr()
-is called, a zero reference will track this change.
-
-If subsequent calls to PacketAliasRedirectAddr()
-use the same aliasing address, all new incoming
-traffic to this aliasing address will be redirected
-to the local address made in the last function call,
-but new traffic all of the local machines designated
-in the several function calls will be aliased to
-the same address.  Consider the following example:
-.Bd -literal -offset left
-    PacketAliasRedirectAddr(inet_aton("192.168.0.2"),
-                            inet_aton("141.221.254.101"));
-    PacketAliasRedirectAddr(inet_aton("192.168.0.3"),
-                            inet_aton("141.221.254.101"));
-    PacketAliasRedirectAddr(inet_aton("192.168.0.4"),
-                            inet_aton("141.221.254.101"));
-.Ed
-
-Any outgoing connections such as telnet or ftp
-from 192.168.0.2, 102.168.0.3, 192.168.0.4 will
-appear to come from 141.221.254.101.  Any incoming
-connections to 141.221.254.101 will be directed
-to 192.168.0.4.
-
-Any calls to PacketAliasRedirectPort() will
-have precedence over address mappings designated
-by PacketAliasRedirectAddr().
-
-This function returns a pointer which can subsequently
-be used by PacketAliasRedirectDelete().  If NULL is
-returned, then the function call did not complete
-successfully.
-.Ss 4.3 PacketAliasRedirectDelete()
-
-.Ft void
-.Fn PacketAliasRedirectDelete "struct alias_link *ptr"
-
-This function will delete a specific static redirect
-rule entered by PacketAliasRedirectPort() or
-PacketAliasRedirectAddr().  The parameter
-.Em ptr 
-is the pointer returned by either of the redirection
-functions.  If an invalid pointer is passed to
-PacketAliasRedirectDelete(), then a program crash
-or unpredictable operation could result, so it is
-necessary to be careful using this function.
-
-.Sh 5. Fragment Handling
-The functions in this section are used to deal with
-incoming fragments.
-
-Outgoing fragments are handled within PacketAliasOut()
-by changing the address according to any
-applicable mapping set by PacketAliasRedirectAddress(),
-or the default aliasing address set by
-PacketAliasSetAddress().
- 
-Incoming fragments are handled in one of two ways.
-If the header of a fragmented IP packet has already
-been seen, then all subsequent fragments will be
-re-mapped in the same manner the header fragment
-was.  Fragments which arrive before the header
-are saved and then retrieved once the header fragment
-has been resolved.
-.Ss 5.1 PacketAliasSaveFragment()
-
-.Ft int
-.Fn PacketAliasSaveFragment "char *ptr"
-
-When PacketAliasIn() returns
-PKT_ALIAS_UNRESOLVED_FRAGMENT, this
-function can be used to save the pointer to
-the unresolved fragment.
-
-It is implicitly assumed that
-.Em ptr
-points to a block of memory allocated by
-malloc().  If the fragment is never
-resolved, the packet aliasing engine will
-automatically free the memory after a
-timeout period. [Eventually this function
-should be modified so that a callback 
-function for freeing memory is passed as
-an argument.]
-
-This function returns PKT_ALIAS_OK if it
-was successful and PKT_ALIAS_ERROR if there
-was an error.
-.Ss 5.2 PacketAliasGetNextFragment()
-
-.Ft char *
-.Fn PacketAliasGetFragment "char *buffer"
-
-This function can be used to retrieve fragment
-pointers saved by PacketAliasSaveFragment().
-The IP header fragment pointed to by
-Em buffer
-is the header fragment indicated when
-PacketAliasIn() returns PKT_ALIAS_FOUND_HEADER_FRAGMENT.
-Once a a fragment pointer is retrieved, it
-becomes the calling program's responsibility
-to free the dynamically allocated memory for
-the fragment.
-
-PacketAliasGetFragment() can be called
-sequentially until there are no more fragments
-available, at which time it returns NULL.
-.Ss 5.3 PacketAliasFragmentIn()
-
-.Ft void
-.Fn PacketAliasFragmentIn "char *header" "char *fragment" 
-
-When a fragment is retrieved with
-PacketAliasGetFragment(), it can then be
-de-aliased with a call to PacketAliasFragmentIn().
-.Em header 
-is the pointer to a header fragment used as a
-template, and
-.Em fragment
-is the pointer to the packet to be de-aliased.
-
-.Sh 6. Miscellaneous Functions
-
-.Ss 6.1 PacketAliasSetTarget()
-
-.Ft void
-.Fn PacketAliasSetTarget "struct in_addr addr"
-
-When an incoming packet not associated with
-any pre-existing aliasing link arrives at the
-host machine, it will be sent to the address
-indicated by a call to PacketAliasSetTarget().
-
-If this function is not called, or is called
-with a zero address argument, then all new
-incoming packets go to the address set by
-PacketAliasSetAddress.
-.Ss 6.2 PacketAliasCheckNewLink()
-
-.Ft int
-.Fn PacketAliasCheckNewLink "void"
-
-This function returns a non-zero value when
-a new aliasing link is created.  In circumstances
-where incoming traffic is being sequentially
-sent to different local servers, this function
-can be used to trigger when PacketAliasSetTarget()
-is called to change the default target address.
-.Ss 6.3 PacketAliasInternetChecksum() 
-
-.Ft u_short
-.Fn PacketAliasInternetChecksum "u_short *buffer" "int nbytes"
-
-This is a utility function that does not seem
-to be available elswhere and is included as a
-convenience.  It computes the internet checksum,
-which is used in both IP and protocol-specific
-headers (TCP, UDP, ICMP).  
-
-.Em buffer 
-points to the data block to be checksummed, and
-.Em nbytes
-is the number of bytes.  The 16-bit checksum
-field should be zeroed before computing the checksum.
-
-Checksums can also be verified by operating on a block
-of data including its checksum.  If the checksum is
-valid, PacketAliasInternetChecksum() will return zero.
-
-.Sh 7. Authors
-Charles Mott (cmott@srv.net), versions 1.0 - 1.8, 2.0 - 2.4. 
-
-Eivind Eklund (eivind@freebsd.org), versions 1.8b, 1.9 and
-2.5.  Added IRC DCC support as well as contributing a number of
-architectural improvements; added the firewall bypass
-for FTP/IRC DCC.
-
-.Sh 8. Acknowledgments
-
-Listed below, in approximate chronological
-order, are individuals who have provided
-valuable comments and/or debugging assistance.
-
-.Bl -inset -compact -offset left
-.It Gary Roberts
-.It Tom Torrance
-.It Reto Burkhalter
-.It Martin Renters
-.It Brian Somers
-.It Paul Traina
-.It Ari Suutari
-.It Dave Remien
-.It J. Fortes
-.It Andrzej Bialeki
-.It Gordon Burditt
-.El
-
-.Sh Appendix: Conceptual Background
-This appendix is intended for those who
-are planning to modify the source code or want
-to create somewhat esoteric applications using
-the packet aliasing functions.
-
-The conceptual framework under which the
-packet aliasing engine operates is described here.
-Central to the discussion is the idea of an
-"aliasing link" which  describes the relationship
-for a given packet transaction between the local
-machine, aliased identity and remote machine.  It
-is discussed how such links come into existence
-and are destroyed.
-.Ss A.1 Aliasing Links
-There is a notion of an "aliasing link",
-which is 7-tuple describing a specific
-translation:
-.Bd -literal -offset indent
-(local addr, local port, alias addr, alias port,
- remote addr, remote port, protocol)
-.Ed
-
-Outgoing packets have the local address and
-port number replaced with the alias address
-and port number.  Incoming packets undergo the
-reverse process.  The packet aliasing engine
-attempts to match packets against an internal
-table of aliasing links to determine how to
-modify a given IP packet.  Both the IP
-header and protocol dependent headers are
-modified as necessary.  Aliasing links are
-created and deleted as necessary according
-to network traffic.
-
-Protocols can be TCP, UDP or even ICMP in
-certain circumstances.  (Some types of ICMP
-packets can be aliased according to sequence
-or id number which acts as an equivalent port
-number for identifying how individual packets
-should be handled.)
-
-Each aliasing link must have a unique
-combination of the following five quanties:
-alias address/port, remote address/port
-and protocol.  This ensures that several
-machines on a local network can share the
-same aliased IP address.  In cases where
-conflicts might arise, the aliasing port
-is chosen so that uniqueness is maintained.
-.Ss A.2 Static and Dynamic Links
-Aliasing links can either be static or dynamic.
-Static links persist indefinitely and represent
-fixed rules for translating IP packets.  Dynamic
-links come into existence for a specific TCP
-connection or UDP transaction or ICMP echo
-sequence.  For the case of TCP, the connection
-can be monitored to see when the associated
-aliasing link should be deleted.  Aliasing links
-for UDP transactions (and ICMP echo and timestamp
-equests) work on a simple timeout rule.  When
-no activity is observed on a dynamic link for
-a certain amount of time it is automatically
-deleted.  Timeout rules also apply to TCP
-connections which do not open or close
-properly.
-.Ss A.3 Partially Specified Aliasing Links
-Aliasing links can be partially specified,
-meaning that the remote address and/or remote
-ports are unkown.  In this case, when a packet
-matching the incomplete specification is found,
-a fully specified dynamic link is created.  If
-the original partially specified link is dynamic,
-it will be deleted after the fully specified link
-is created, otherwise it will persist.
-
-For instance, a partially specified link might
-be
-.Bd -literal -offset indent
-(192.168.0.4, 23, 204.228.203.215, 8066, 0, 0, tcp)
-.Ed
-
-The zeros denote unspecified components for
-the remote address and port.  If this link were
-static it would have the effect of redirecting
-all incoming traffic from port 8066 of
-204.228.203.215 to port 23 (telnet) of machine
-192.168.0.4 on the local network.  Each
-individual telnet connection would initiate
-the creation of a distinct dynamic link.
-.Ss A.4 Dynamic Link Creation
-In addition to aliasing links, there are
-also address mappings that can be stored
-within the internal data table of the packet
-aliasing mechanism.
-.Bd -literal -offset indent
-(local addr, alias addr)
-.Ed
-
-Address mappings are searched when creating
-new dynamic links.
-
-All outgoing packets from the local network
-automatically create a dynamic link if
-they do not match an already existing fully
-specified link.  If an address mapping exists
-for the the outgoing packet, this determines
-the alias address to be used.  If no mapping
-exists, then a default address, usually the
-address of the packet aliasing host, is used.
-If necessary, this default address can be
-changed as often as each indvidual packet
-arrives.
-
-The aliasing port number is determined
-such that the new dynamic link does not
-conflict with any existing links.  In the
-default operating mode, the packet aliasing
-engine attempts to set the aliasing port
-equal to the local port number.  If this
-results in a conflict, then port numbers
-are randomly chosen until a unique aliasing
-link can be established.  In an alternate
-operating mode, the first choice of an
-aliasing port is also random and unrelated
-to the local port number.
-
diff --git a/usr.sbin/ppp/libalias/shlib_version b/usr.sbin/ppp/libalias/shlib_version
deleted file mode 100644
index c29621c831e..00000000000
--- a/usr.sbin/ppp/libalias/shlib_version
+++ /dev/null
@@ -1,2 +0,0 @@
-major=2
-minor=5