2000-11-25 Antti P Miettinen <antti.p.miettinen@nokia.com>

	* wrapup/Makefile.am: Added modem subdir.
	* configure.in, Makefile.am: Added modem subdir.
	* net/Makefile.am: Added if_pppvar.h, pppcompress.h.
	* pppd/Makefile.am: Added pppmain.c (which needs work).
	* pppd/chat.c, pppd/fsm.c, pppd/fsm.h, pppd/ipxcp.c, pppd/main.c,
	pppd/ppp_tty.c, pppd/upap.c: Changes from Thomas Doerfler
	<Thomas.Doerfler@imd-systems.de> and cosmetic changes by me.
	Actually main.c and ppp_tty.c should be scratched. The modem
	subdir has the real ppp_tty.c and the real pppd main is in pppmain.c.

11 files changed, 5108 insertions, 0 deletions

diff --git a/c/src/exec/libnetworking/net/if_pppvar.h b/c/src/exec/libnetworking/net/if_pppvar.h
new file mode 100644
index 0000000000..6eb45a6afb
--- /dev/null
+++ b/c/src/exec/libnetworking/net/if_pppvar.h
@@ -0,0 +1,111 @@
+/*	$Id$	*/
+/*
+ * if_pppvar.h - private structures and declarations for PPP.
+ *
+ * Copyright (c) 1994 The Australian National University.
+ * All rights reserved.
+ *
+ * Permission to use, copy, modify, and distribute this software and its
+ * documentation is hereby granted, provided that the above copyright
+ * notice appears in all copies.  This software is provided without any
+ * warranty, express or implied. The Australian National University
+ * makes no representations about the suitability of this software for
+ * any purpose.
+ *
+ * IN NO EVENT SHALL THE AUSTRALIAN NATIONAL UNIVERSITY BE LIABLE TO ANY
+ * PARTY FOR DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
+ * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN IF
+ * THE AUSTRALIAN NATIONAL UNIVERSITY HAVE BEEN ADVISED OF THE POSSIBILITY
+ * OF SUCH DAMAGE.
+ *
+ * THE AUSTRALIAN NATIONAL UNIVERSITY SPECIFICALLY DISCLAIMS ANY WARRANTIES,
+ * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
+ * AND FITNESS FOR A PARTICULAR PURPOSE.  THE SOFTWARE PROVIDED HEREUNDER IS
+ * ON AN "AS IS" BASIS, AND THE AUSTRALIAN NATIONAL UNIVERSITY HAS NO
+ * OBLIGATION TO PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS,
+ * OR MODIFICATIONS.
+ *
+ * Copyright (c) 1989 Carnegie Mellon University.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms are permitted
+ * provided that the above copyright notice and this paragraph are
+ * duplicated in all such forms and that any documentation,
+ * advertising materials, and other materials related to such
+ * distribution and use acknowledge that the software was developed
+ * by Carnegie Mellon University.  The name of the
+ * University may not be used to endorse or promote products derived
+ * from this software without specific prior written permission.
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
+ * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
+ */
+
+/*
+ * Supported network protocols.  These values are used for
+ * indexing sc_npmode.
+ */
+#define NP_IP	0		/* Internet Protocol */
+#define NUM_NP	1		/* Number of NPs. */
+
+/*
+ * Structure describing each ppp unit.
+ */
+struct ppp_softc {
+	struct	ifnet sc_if;		/* network-visible interface */
+	u_int	sc_flags;		/* control/status bits; see if_ppp.h */
+	void	*sc_devp;		/* pointer to device-dep structure */
+	void	(*sc_start) __P((struct ppp_softc *));	/* start output proc */
+	void	(*sc_ctlp) __P((struct ppp_softc *)); /* rcvd control pkt */
+	void	(*sc_relinq) __P((struct ppp_softc *)); /* relinquish ifunit */
+	short	sc_mru;			/* max receive unit */
+	pid_t	sc_xfer;		/* used in transferring unit */
+	struct	ifqueue sc_rawq;	/* received packets */
+	struct	ifqueue sc_inq;		/* queue of input packets for daemon */
+	struct	ifqueue sc_fastq;	/* interactive output packet q */
+	struct	mbuf *sc_togo;		/* output packet ready to go */
+	struct	mbuf *sc_npqueue;	/* output packets not to be sent yet */
+	struct	mbuf **sc_npqtail;	/* ptr to last next ptr in npqueue */
+	struct	pppstat sc_stats;	/* count of bytes/pkts sent/rcvd */
+	caddr_t	sc_bpf;			/* hook for BPF */
+	enum	NPmode sc_npmode[NUM_NP]; /* what to do with each NP */
+	struct	compressor *sc_xcomp;	/* transmit compressor */
+	void	*sc_xc_state;		/* transmit compressor state */
+	struct	compressor *sc_rcomp;	/* receive decompressor */
+	void	*sc_rc_state;		/* receive decompressor state */
+	time_t	sc_last_sent;		/* time (secs) last NP pkt sent */
+	time_t	sc_last_recv;		/* time (secs) last NP pkt rcvd */
+#ifdef PPP_FILTER
+	struct	bpf_program sc_pass_filt;   /* filter for packets to pass */
+	struct	bpf_program sc_active_filt; /* filter for "non-idle" packets */
+#endif /* PPP_FILTER */
+#ifdef	VJC
+	struct	vjcompress *sc_comp; 	/* vjc control buffer */
+#endif
+
+	/* Device-dependent part for async lines. */
+	ext_accm sc_asyncmap;		/* async control character map */
+	u_long	sc_rasyncmap;		/* receive async control char map */
+	struct	mbuf *sc_outm;		/* mbuf chain currently being output */
+	struct	mbuf *sc_m;		/* pointer to input mbuf chain */
+	struct	mbuf *sc_mc;		/* pointer to current input mbuf */
+	char	*sc_mp;			/* ptr to next char in input mbuf */
+	short	sc_ilen;		/* length of input packet so far */
+	u_short	sc_fcs;			/* FCS so far (input) */
+	u_short	sc_outfcs;		/* FCS so far for output packet */
+	u_char	sc_rawin[16];		/* chars as received */
+	int	sc_rawin_count;		/* # in sc_rawin */
+        rtems_id sem_id;                /* ID of comm semaphore         */
+};
+
+struct	ppp_softc ppp_softc[NPPP];
+
+struct	ppp_softc *pppalloc __P((pid_t pid));
+void	pppdealloc __P((struct ppp_softc *sc));
+int	pppoutput __P((struct ifnet *, struct mbuf *,
+		       struct sockaddr *, struct rtentry *));
+int	pppioctl __P((struct ppp_softc *sc, int cmd, caddr_t data,
+		      int flag, struct proc *p));
+void	ppp_restart __P((struct ppp_softc *sc));
+void	ppppktin __P((struct ppp_softc *sc, struct mbuf *m, int lost));
+struct	mbuf *ppp_dequeue __P((struct ppp_softc *sc));
diff --git a/c/src/exec/libnetworking/net/pppcompress.h b/c/src/exec/libnetworking/net/pppcompress.h
new file mode 100644
index 0000000000..3f7687e6bb
--- /dev/null
+++ b/c/src/exec/libnetworking/net/pppcompress.h
@@ -0,0 +1,164 @@
+/*
+ * Definitions for tcp compression routines.
+ *
+ * Copyright (c) 1989 Regents of the University of California.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. All advertising materials mentioning features or use of this software
+ *    must display the following acknowledgement:
+ *	This product includes software developed by the University of
+ *	California, Berkeley and its contributors.
+ * 4. Neither the name of the University nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ *	Van Jacobson (van@helios.ee.lbl.gov), Dec 31, 1989:
+ *	- Initial distribution.
+ *
+ *	From: 	slcompress.h	7.4	90/06/28
+ *	$Id$
+ */
+
+#ifndef _NET_PPPCOMPRESS_H_
+#define _NET_PPPCOMPRESS_H_
+
+#define MAX_STATES 16		/* must be > 2 and < 256 */
+#define MAX_HDR MLEN		/* XXX 4bsd-ism: should really be 128 */
+
+/*
+ * Compressed packet format:
+ *
+ * The first octet contains the packet type (top 3 bits), TCP
+ * 'push' bit, and flags that indicate which of the 4 TCP sequence
+ * numbers have changed (bottom 5 bits).  The next octet is a
+ * conversation number that associates a saved IP/TCP header with
+ * the compressed packet.  The next two octets are the TCP checksum
+ * from the original datagram.  The next 0 to 15 octets are
+ * sequence number changes, one change per bit set in the header
+ * (there may be no changes and there are two special cases where
+ * the receiver implicitly knows what changed -- see below).
+ * 
+ * There are 5 numbers which can change (they are always inserted
+ * in the following order): TCP urgent pointer, window,
+ * acknowlegement, sequence number and IP ID.  (The urgent pointer
+ * is different from the others in that its value is sent, not the
+ * change in value.)  Since typical use of SLIP links is biased
+ * toward small packets (see comments on MTU/MSS below), changes
+ * use a variable length coding with one octet for numbers in the
+ * range 1 - 255 and 3 octets (0, MSB, LSB) for numbers in the
+ * range 256 - 65535 or 0.  (If the change in sequence number or
+ * ack is more than 65535, an uncompressed packet is sent.)
+ */
+
+/*
+ * Packet types (must not conflict with IP protocol version)
+ *
+ * The top nibble of the first octet is the packet type.  There are
+ * three possible types: IP (not proto TCP or tcp with one of the
+ * control flags set); uncompressed TCP (a normal IP/TCP packet but
+ * with the 8-bit protocol field replaced by an 8-bit connection id --
+ * this type of packet syncs the sender & receiver); and compressed
+ * TCP (described above).
+ *
+ * LSB of 4-bit field is TCP "PUSH" bit (a worthless anachronism) and
+ * is logically part of the 4-bit "changes" field that follows.  Top
+ * three bits are actual packet type.  For backward compatibility
+ * and in the interest of conserving bits, numbers are chosen so the
+ * IP protocol version number (4) which normally appears in this nibble
+ * means "IP packet".
+ */
+
+/* packet types */
+#define TYPE_IP 0x40
+#define TYPE_UNCOMPRESSED_TCP 0x70
+#define TYPE_COMPRESSED_TCP 0x80
+#define TYPE_ERROR 0x00
+
+/* Bits in first octet of compressed packet */
+#define NEW_C	0x40	/* flag bits for what changed in a packet */
+#define NEW_I	0x20
+#define NEW_S	0x08
+#define NEW_A	0x04
+#define NEW_W	0x02
+#define NEW_U	0x01
+
+/* reserved, special-case values of above */
+#define SPECIAL_I (NEW_S|NEW_W|NEW_U)		/* echoed interactive traffic */
+#define SPECIAL_D (NEW_S|NEW_A|NEW_W|NEW_U)	/* unidirectional data */
+#define SPECIALS_MASK (NEW_S|NEW_A|NEW_W|NEW_U)
+
+#define TCP_PUSH_BIT 0x10
+
+
+/*
+ * "state" data for each active tcp conversation on the wire.  This is
+ * basically a copy of the entire IP/TCP header from the last packet
+ * we saw from the conversation together with a small identifier
+ * the transmit & receive ends of the line use to locate saved header.
+ */
+struct cstate {
+	struct cstate *cs_next;	/* next most recently used cstate (xmit only) */
+	u_short cs_hlen;	/* size of hdr (receive only) */
+	u_char cs_id;		/* connection # associated with this state */
+	u_char cs_filler;
+	union {
+		char csu_hdr[MAX_HDR];
+		struct ip csu_ip;	/* ip/tcp hdr from most recent packet */
+	} slcs_u;
+};
+#define cs_ip slcs_u.csu_ip
+#define cs_hdr slcs_u.csu_hdr
+
+/*
+ * all the state data for one serial line (we need one of these
+ * per line).
+ */
+struct vjcompress {
+	struct cstate *last_cs;	/* most recently used tstate */
+	u_char last_recv;	/* last rcvd conn. id */
+	u_char last_xmit;	/* last sent conn. id */
+	u_short flags;
+#ifndef SL_NO_STATS
+	int sls_packets;	/* outbound packets */
+	int sls_compressed;	/* outbound compressed packets */
+	int sls_searches;	/* searches for connection state */
+	int sls_misses;		/* times couldn't find conn. state */
+	int sls_uncompressedin;	/* inbound uncompressed packets */
+	int sls_compressedin;	/* inbound compressed packets */
+	int sls_errorin;	/* inbound unknown type packets */
+	int sls_tossed;		/* inbound packets tossed because of error */
+#endif
+	struct cstate tstate[MAX_STATES];	/* xmit connection states */
+	struct cstate rstate[MAX_STATES];	/* receive connection states */
+};
+/* flag values */
+#define SLF_TOSS 1		/* tossing rcvd frames because of input err */
+
+void	 vj_compress_init __P((struct vjcompress *, int));
+u_int	 vj_compress_tcp __P((struct mbuf *,
+	    struct ip *, struct vjcompress *, int));
+int	 vj_uncompress_tcp __P((u_char **, int, u_int, struct vjcompress *));
+int	 vj_uncompress_tcp_core __P((u_char *, int, int, u_int,
+	    struct vjcompress *, u_char **, u_int *));
+
+#endif /* _NET_PPPCOMPRESS_H_ */
diff --git a/c/src/libnetworking/modem/.cvsignore b/c/src/libnetworking/modem/.cvsignore
new file mode 100644
index 0000000000..282522db03
--- /dev/null
+++ b/c/src/libnetworking/modem/.cvsignore
@@ -0,0 +1,2 @@
+Makefile
+Makefile.in
diff --git a/c/src/libnetworking/modem/Makefile.am b/c/src/libnetworking/modem/Makefile.am
new file mode 100644
index 0000000000..86560501b4
--- /dev/null
+++ b/c/src/libnetworking/modem/Makefile.am
@@ -0,0 +1,39 @@
+##
+## $Id $
+##
+
+AUTOMAKE_OPTIONS = foreign 1.4
+
+LIBNAME = lib.a
+LIB = $(ARCH)/$(LIBNAME)
+
+C_FILES = ppp_tty.c ppp.c pppcompress.c
+C_O_FILES = $(C_FILES:%.c=$(ARCH)/%.o)
+
+OBJS = $(C_O_FILES)
+
+include $(RTEMS_ROOT)/make/custom/@RTEMS_BSP@.cfg
+include $(top_srcdir)/../../../automake/compile.am
+include $(top_srcdir)/../../../automake/lib.am
+
+#
+# Add local stuff here using +=
+#
+
+# DEFINES += -D_COMPILING_BSD_KERNEL_ -DKERNEL -DINET -DNFS -DDIAGNOSTIC \
+#     -DBOOTP_COMPAT
+
+AM_CPPFLAGS += -D__INSIDE_RTEMS_BSD_TCPIP_STACK__ \
+-D_COMPILING_BSD_KERNEL_ -DKERNEL -DINET -DNFS -DDIAGNOSTIC \
+-DBOOTP_COMPAT
+
+$(LIB): $(OBJS)
+	$(make-library)
+
+all-local: $(ARCH) $(OBJS) $(LIB)
+
+.PRECIOUS: $(LIB)
+
+EXTRA_DIST = ppp_tty.c ppp.c ppp.h pppcompress.c
+
+include $(top_srcdir)/../../../automake/local.am
diff --git a/c/src/libnetworking/modem/ppp.c b/c/src/libnetworking/modem/ppp.c
new file mode 100644
index 0000000000..9b31b678fb
--- /dev/null
+++ b/c/src/libnetworking/modem/ppp.c
@@ -0,0 +1,1507 @@
+/*
+ * if_ppp.c - Point-to-Point Protocol (PPP) Asynchronous driver.
+ *
+ * Copyright (c) 1989 Carnegie Mellon University.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms are permitted
+ * provided that the above copyright notice and this paragraph are
+ * duplicated in all such forms and that any documentation,
+ * advertising materials, and other materials related to such
+ * distribution and use acknowledge that the software was developed
+ * by Carnegie Mellon University.  The name of the
+ * University may not be used to endorse or promote products derived
+ * from this software without specific prior written permission.
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
+ * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
+ *
+ * Drew D. Perkins
+ * Carnegie Mellon University
+ * 4910 Forbes Ave.
+ * Pittsburgh, PA 15213
+ * (412) 268-8576
+ * ddp@andrew.cmu.edu
+ *
+ * Based on:
+ *	@(#)if_sl.c	7.6.1.2 (Berkeley) 2/15/89
+ *
+ * Copyright (c) 1987 Regents of the University of California.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms are permitted
+ * provided that the above copyright notice and this paragraph are
+ * duplicated in all such forms and that any documentation,
+ * advertising materials, and other materials related to such
+ * distribution and use acknowledge that the software was developed
+ * by the University of California, Berkeley.  The name of the
+ * University may not be used to endorse or promote products derived
+ * from this software without specific prior written permission.
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
+ * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
+ *
+ * Serial Line interface
+ *
+ * Rick Adams
+ * Center for Seismic Studies
+ * 1300 N 17th Street, Suite 1450
+ * Arlington, Virginia 22209
+ * (703)276-7900
+ * rick@seismo.ARPA
+ * seismo!rick
+ *
+ * Pounded on heavily by Chris Torek (chris@mimsy.umd.edu, umcp-cs!chris).
+ * Converted to 4.3BSD Beta by Chris Torek.
+ * Other changes made at Berkeley, based in part on code by Kirk Smith.
+ *
+ * Converted to 4.3BSD+ 386BSD by Brad Parker (brad@cayman.com)
+ * Added VJ tcp header compression; more unified ioctls
+ *
+ * Extensively modified by Paul Mackerras (paulus@cs.anu.edu.au).
+ * Cleaned up a lot of the mbuf-related code to fix bugs that
+ * caused system crashes and packet corruption.  Changed pppstart
+ * so that it doesn't just give up with a collision if the whole
+ * packet doesn't fit in the output ring buffer.
+ *
+ * Added priority queueing for interactive IP packets, following
+ * the model of if_sl.c, plus hooks for bpf.
+ * Paul Mackerras (paulus@cs.anu.edu.au).
+ */
+
+/* $Id$ */
+/* from if_sl.c,v 1.11 84/10/04 12:54:47 rick Exp */
+/* from NetBSD: if_ppp.c,v 1.15.2.2 1994/07/28 05:17:58 cgd Exp */
+
+#include "ppp.h"
+#if NPPP > 0
+/* na razie wylaczmy kompresje*/
+
+#include <rtems/rtems_bsdnet.h> /* to get right defines */
+
+#include <sys/param.h>
+#include <sys/systm.h>
+#include <sys/proc.h>
+#include <sys/mbuf.h>
+#include <sys/socket.h>
+#include <sys/ioctl.h>
+#include <sys/kernel.h>
+#include <sys/time.h>
+#include <sys/malloc.h>
+
+#include <rtems/rtems_bsdnet.h>
+#include <net/if.h>
+#include <sys/errno.h>
+#include <net/if_types.h>
+#include <net/netisr.h>
+#include <net/route.h>
+#ifdef PPP_FILTER
+#include <net/bpf.h>
+#endif
+
+#ifdef INET
+#include <netinet/in.h>
+#include <netinet/in_systm.h>
+#include <netinet/in_var.h>
+#include <netinet/ip.h>
+#endif
+
+#include <bpfilter.h>
+#if NBPFILTER > 0
+#include <net/bpf.h>
+#endif
+
+#ifdef VJC
+#include <net/pppcompress.h>
+#endif
+
+#include <net/ppp_defs.h>
+#include <net/if_ppp.h>
+#include <net/if_pppvar.h>
+#include <machine/cpu.h>
+
+#define splsoftnet	splnet
+
+#ifndef NETISR_PPP
+/* This definition should be moved to net/netisr.h */
+#define NETISR_PPP	26	/* PPP software interrupt */
+#endif
+
+#ifdef PPP_COMPRESS
+#define PACKETPTR	struct mbuf *
+#include <net/ppp-comp.h>
+#endif
+extern struct	ifqueue ipintrq;
+static int	pppsioctl __P((struct ifnet *, int, caddr_t));
+static void	ppp_requeue __P((struct ppp_softc *));
+static void	ppp_ccp __P((struct ppp_softc *, struct mbuf *m, int rcvd));
+static void	ppp_ccp_closed __P((struct ppp_softc *));
+static void	ppp_inproc __P((struct ppp_softc *, struct mbuf *));
+static void	pppdumpm __P((struct mbuf *m0));
+
+/*
+ * Some useful mbuf macros not in mbuf.h.
+ */
+#define M_IS_CLUSTER(m)	((m)->m_flags & M_EXT)
+
+#define M_DATASTART(m)	\
+	(M_IS_CLUSTER(m) ? (m)->m_ext.ext_buf : \
+	    (m)->m_flags & M_PKTHDR ? (m)->m_pktdat : (m)->m_dat)
+
+#define M_DATASIZE(m)	\
+	(M_IS_CLUSTER(m) ? (m)->m_ext.ext_size : \
+	    (m)->m_flags & M_PKTHDR ? MHLEN: MLEN)
+
+/*
+ * We steal two bits in the mbuf m_flags, to mark high-priority packets
+ * for output, and received packets following lost/corrupted packets.
+ */
+#define M_HIGHPRI	0x2000	/* output packet for sc_fastq */
+#define M_ERRMARK	0x4000	/* steal a bit in mbuf m_flags */
+
+
+#ifdef PPP_COMPRESS
+/*
+ * List of compressors we know about.
+ * We leave some space so maybe we can modload compressors.
+ */
+
+extern struct compressor ppp_bsd_compress;
+extern struct compressor ppp_deflate, ppp_deflate_draft;
+
+
+struct compressor *ppp_compressors[8] = {
+#if DO_BSD_COMPRESS
+    &ppp_bsd_compress,
+#endif
+#if DO_DEFLATE
+    &ppp_deflate,
+    &ppp_deflate_draft,
+#endif
+    NULL
+};
+#endif /* PPP_COMPRESS */
+static struct timeval ppp_time;
+
+TEXT_SET(pseudo_set, pppattach);
+
+/*
+ * Called from boot code to establish ppp interfaces.
+ */
+int rtems_ppp_driver_attach (struct rtems_bsdnet_ifconfig *config,
+			     int attaching)
+{
+    register struct ppp_softc *sc;
+    register int i = 0;
+    extern void (*netisrs[])__P((void));
+
+    for (sc = ppp_softc; i < NPPP; sc++) {
+	sc->sc_if.if_name = "ppp";
+	sc->sc_if.if_unit = i++;
+	sc->sc_if.if_mtu = PPP_MTU;
+	sc->sc_if.if_flags = IFF_POINTOPOINT | IFF_MULTICAST;
+	sc->sc_if.if_type = IFT_PPP;
+	sc->sc_if.if_hdrlen = PPP_HDRLEN;
+	sc->sc_if.if_ioctl = pppsioctl;
+	sc->sc_if.if_output = pppoutput;
+	sc->sc_if.if_snd.ifq_maxlen = IFQ_MAXLEN;
+	sc->sc_inq.ifq_maxlen = IFQ_MAXLEN;
+	sc->sc_fastq.ifq_maxlen = IFQ_MAXLEN;
+	sc->sc_rawq.ifq_maxlen = IFQ_MAXLEN;
+	if_attach(&sc->sc_if);
+#if NBPFILTER > 0
+	bpfattach(&sc->sc_bpf, &sc->sc_if, DLT_PPP, PPP_HDRLEN);
+#endif
+    }
+/* wpisane na twardo do rtems_glue.c
+    netisrs[NETISR_PPP] = pppintr; */
+	return 1;
+}
+
+/*
+ * Allocate a ppp interface unit and initialize it.
+ */
+struct ppp_softc *
+pppalloc(pid)
+    pid_t pid;
+{
+    int nppp, i;
+    struct ppp_softc *sc;
+    for (nppp = 0, sc = ppp_softc; nppp < NPPP; nppp++, sc++)
+	if (sc->sc_xfer == pid) {
+	    sc->sc_xfer = 0;
+	    return sc;
+	}
+    for (nppp = 0, sc = ppp_softc; nppp < NPPP; nppp++, sc++)
+	if (sc->sc_devp == NULL)
+	    break;
+    if (nppp >= NPPP)
+	return NULL;
+
+    sc->sc_flags = 0;
+    sc->sc_mru = PPP_MRU;
+    sc->sc_relinq = NULL;
+    bzero((char *)&sc->sc_stats, sizeof(sc->sc_stats));
+#ifdef VJC
+    sc->sc_comp=malloc(sizeof(struct vjcompress),M_DEVBUF, M_NOWAIT);
+    if (sc->sc_comp)
+	vj_compress_init(sc->sc_comp, -1);
+#endif
+#ifdef PPP_COMPRESS
+    sc->sc_xc_state = NULL;
+    sc->sc_rc_state = NULL;
+#endif /* PPP_COMPRESS */
+    for (i = 0; i < NUM_NP; ++i)
+	sc->sc_npmode[i] = NPMODE_ERROR;
+    sc->sc_npqueue = NULL;
+    sc->sc_npqtail = &sc->sc_npqueue;
+	 microtime(&ppp_time);
+    sc->sc_last_sent = sc->sc_last_recv = ppp_time.tv_sec;
+
+    return sc;
+}
+
+/*
+ * Deallocate a ppp unit.  Must be called at splsoftnet or higher.
+ */
+void
+pppdealloc(sc)
+    struct ppp_softc *sc;
+{
+    struct mbuf *m;
+
+    if_down(&sc->sc_if);
+    sc->sc_if.if_flags &= ~(IFF_UP|IFF_RUNNING);
+    sc->sc_devp = NULL;
+    sc->sc_xfer = 0;
+    for (;;) {
+	IF_DEQUEUE(&sc->sc_rawq, m);
+	if (m == NULL)
+	    break;
+	m_freem(m);
+    }
+    for (;;) {
+	IF_DEQUEUE(&sc->sc_inq, m);
+	if (m == NULL)
+	    break;
+	m_freem(m);
+    }
+    for (;;) {
+	IF_DEQUEUE(&sc->sc_fastq, m);
+	if (m == NULL)
+	    break;
+	m_freem(m);
+    }
+    while ((m = sc->sc_npqueue) != NULL) {
+	sc->sc_npqueue = m->m_nextpkt;
+	m_freem(m);
+    }
+    if (sc->sc_togo != NULL) {
+	m_freem(sc->sc_togo);
+	sc->sc_togo = NULL;
+    }
+#ifdef PPP_COMPRESS
+    ppp_ccp_closed(sc);
+    sc->sc_xc_state = NULL;
+    sc->sc_rc_state = NULL;
+#endif /* PPP_COMPRESS */
+#ifdef PPP_FILTER
+    if (sc->sc_pass_filt.bf_insns != 0) {
+	free(sc->sc_pass_filt.bf_insns, M_DEVBUF);
+	sc->sc_pass_filt.bf_insns = 0;
+	sc->sc_pass_filt.bf_len = 0;
+    }
+    if (sc->sc_active_filt.bf_insns != 0) {
+	free(sc->sc_active_filt.bf_insns, M_DEVBUF);
+	sc->sc_active_filt.bf_insns = 0;
+	sc->sc_active_filt.bf_len = 0;
+    }
+#endif /* PPP_FILTER */
+#ifdef VJC
+    if (sc->sc_comp != 0) {
+	free(sc->sc_comp, M_DEVBUF);
+	sc->sc_comp = 0;
+    }
+#endif
+}
+
+/*
+ * Ioctl routine for generic ppp devices.
+ */
+int
+pppioctl(sc, cmd, data, flag, p)
+    struct ppp_softc *sc;
+    int cmd;
+    caddr_t data;
+    int flag;
+    struct proc *p;
+{
+    int s, error, flags, mru, nb, npx;
+    struct ppp_option_data *odp;
+    struct compressor **cp;
+    struct npioctl *npi;
+    time_t t;
+#ifdef PPP_FILTER
+    struct bpf_program *bp, *nbp;
+    struct bpf_insn *newcode, *oldcode;
+    int newcodelen;
+#endif /* PPP_FILTER */
+#ifdef	PPP_COMPRESS
+    u_char ccp_option[CCP_MAX_OPTION_LENGTH];
+#endif
+
+    switch (cmd) {
+    case FIONREAD:
+	*(int *)data = sc->sc_inq.ifq_len;
+	break;
+
+    case PPPIOCGUNIT:
+	*(int *)data = sc->sc_if.if_unit;
+	break;
+
+    case PPPIOCGFLAGS:
+	*(u_int *)data = sc->sc_flags;
+	break;
+
+    case PPPIOCSFLAGS:
+	flags = *(int *)data & SC_MASK;
+	s = splsoftnet();
+#ifdef PPP_COMPRESS
+	if (sc->sc_flags & SC_CCP_OPEN && !(flags & SC_CCP_OPEN))
+	    ppp_ccp_closed(sc);
+#endif
+	splimp();
+	sc->sc_flags = (sc->sc_flags & ~SC_MASK) | flags;
+	splx(s);
+	break;
+
+    case PPPIOCSMRU:
+	mru = *(int *)data;
+	if (mru >= PPP_MRU && mru <= PPP_MAXMRU)
+	    sc->sc_mru = mru;
+	break;
+
+    case PPPIOCGMRU:
+	*(int *)data = sc->sc_mru;
+	break;
+
+#ifdef VJC
+    case PPPIOCSMAXCID:
+	if (sc->sc_comp) {
+	    s = splsoftnet();
+	    vj_compress_init(sc->sc_comp, *(int *)data);
+	    splx(s);
+	}
+	break;
+#endif
+
+    case PPPIOCXFERUNIT:
+	sc->sc_xfer = 0; /* Always root p->p_pid;*/
+	break;
+
+#ifdef PPP_COMPRESS
+    case PPPIOCSCOMPRESS:
+	odp = (struct ppp_option_data *) data;
+	nb = odp->length;
+	if (nb > sizeof(ccp_option))
+	    nb = sizeof(ccp_option);
+	if ((error = copyin(odp->ptr, ccp_option, nb)) != 0)
+	    return (error);
+	if (ccp_option[1] < 2)	/* preliminary check on the length byte */
+	    return (EINVAL);
+	for (cp = ppp_compressors; *cp != NULL; ++cp)
+	    if ((*cp)->compress_proto == ccp_option[0]) {
+		/*
+		 * Found a handler for the protocol - try to allocate
+		 * a compressor or decompressor.
+		 */
+		error = 0;
+		if (odp->transmit) {
+		    s = splsoftnet();
+		    if (sc->sc_xc_state != NULL)
+			(*sc->sc_xcomp->comp_free)(sc->sc_xc_state);
+		    sc->sc_xcomp = *cp;
+		    sc->sc_xc_state = (*cp)->comp_alloc(ccp_option, nb);
+		    if (sc->sc_xc_state == NULL) {
+			if (sc->sc_flags & SC_DEBUG)
+			    printf("ppp%d: comp_alloc failed\n",
+			       sc->sc_if.if_unit);
+			error = ENOBUFS;
+		    }
+		    splimp();
+		    sc->sc_flags &= ~SC_COMP_RUN;
+		    splx(s);
+		} else {
+		    s = splsoftnet();
+		    if (sc->sc_rc_state != NULL)
+			(*sc->sc_rcomp->decomp_free)(sc->sc_rc_state);
+		    sc->sc_rcomp = *cp;
+		    sc->sc_rc_state = (*cp)->decomp_alloc(ccp_option, nb);
+		    if (sc->sc_rc_state == NULL) {
+			if (sc->sc_flags & SC_DEBUG)
+			    printf("ppp%d: decomp_alloc failed\n",
+			       sc->sc_if.if_unit);
+			error = ENOBUFS;
+		    }
+		    splimp();
+		    sc->sc_flags &= ~SC_DECOMP_RUN;
+		    splx(s);
+		}
+		return (error);
+	    }
+	if (sc->sc_flags & SC_DEBUG)
+	    printf("ppp%d: no compressor for [%x %x %x], %x\n",
+		   sc->sc_if.if_unit, ccp_option[0], ccp_option[1],
+		   ccp_option[2], nb);
+	return (EINVAL);	/* no handler found */
+#endif /* PPP_COMPRESS */
+
+    case PPPIOCGNPMODE:
+    case PPPIOCSNPMODE:
+	npi = (struct npioctl *) data;
+	switch (npi->protocol) {
+	case PPP_IP:
+	    npx = NP_IP;
+	    break;
+	default:
+	    return EINVAL;
+	}
+	if (cmd == PPPIOCGNPMODE) {
+	    npi->mode = sc->sc_npmode[npx];
+	} else {
+	    if (npi->mode != sc->sc_npmode[npx]) {
+		s = splsoftnet();
+		sc->sc_npmode[npx] = npi->mode;
+		if (npi->mode != NPMODE_QUEUE) {
+		    ppp_requeue(sc);
+		    (*sc->sc_start)(sc);
+		}
+		splx(s);
+	    }
+	}
+	break;
+
+    case PPPIOCGIDLE:
+	s = splsoftnet();
+	microtime(&ppp_time);
+	t = ppp_time.tv_sec;
+	((struct ppp_idle *)data)->xmit_idle = t - sc->sc_last_sent;
+	((struct ppp_idle *)data)->recv_idle = t - sc->sc_last_recv;
+	splx(s);
+	break;
+
+#ifdef PPP_FILTER
+    case PPPIOCSPASS:
+    case PPPIOCSACTIVE:
+	nbp = (struct bpf_program *) data;
+	if ((unsigned) nbp->bf_len > BPF_MAXINSNS)
+	    return EINVAL;
+	newcodelen = nbp->bf_len * sizeof(struct bpf_insn);
+	if (newcodelen != 0) {
+	    newcode=(struct bpf_insn *) malloc (newcodelen, M_DEVBUF, M_WAITOK);
+	    if (newcode == 0) {
+		return EINVAL;		/* or sumpin */
+	    }
+	    if ((error = copyin((caddr_t)nbp->bf_insns, (caddr_t)newcode,
+			       newcodelen)) != 0) {
+		free(newcode, M_DEVBUF);
+		return error;
+	    }
+	    if (!bpf_validate(newcode, nbp->bf_len)) {
+		free(newcode, M_DEVBUF);
+		return EINVAL;
+	    }
+	} else
+	    newcode = 0;
+	bp = (cmd == PPPIOCSPASS)? &sc->sc_pass_filt: &sc->sc_active_filt;
+	oldcode = bp->bf_insns;
+	s = splimp();
+	bp->bf_len = nbp->bf_len;
+	bp->bf_insns = newcode;
+	splx(s);
+	if (oldcode != 0)
+	    free(oldcode, M_DEVBUF);
+	break;
+#endif
+
+    default:
+	return (-1);
+    }
+    return (0);
+}
+
+/*
+ * Process an ioctl request to the ppp network interface.
+ */
+static int
+pppsioctl(ifp, cmd, data)
+    register struct ifnet *ifp;
+    int cmd;
+    caddr_t data;
+{
+/*    struct proc *p = curproc;	*//* XXX */
+    register struct ppp_softc *sc = &ppp_softc[ifp->if_unit];
+    register struct ifaddr *ifa = (struct ifaddr *)data;
+    register struct ifreq *ifr = (struct ifreq *)data;
+    struct ppp_stats *psp;
+#ifdef	PPP_COMPRESS
+    struct ppp_comp_stats *pcp;
+#endif
+    int s = splimp(), error = 0;
+
+    switch (cmd) {
+    case SIOCSIFFLAGS:
+	if ((ifp->if_flags & IFF_RUNNING) == 0)
+	    ifp->if_flags &= ~IFF_UP;
+	break;
+
+    case SIOCSIFADDR:
+	if (ifa->ifa_addr->sa_family != AF_INET)
+	    error = EAFNOSUPPORT;
+	break;
+
+    case SIOCSIFDSTADDR:
+	if (ifa->ifa_addr->sa_family != AF_INET)
+	    error = EAFNOSUPPORT;
+	break;
+
+    case SIOCSIFMTU:
+	sc->sc_if.if_mtu = ifr->ifr_mtu;
+	break;
+
+    case SIOCGIFMTU:
+	ifr->ifr_mtu = sc->sc_if.if_mtu;
+	break;
+
+    case SIOCADDMULTI:
+    case SIOCDELMULTI:
+	if (ifr == 0) {
+	    error = EAFNOSUPPORT;
+	    break;
+	}
+	switch(ifr->ifr_addr.sa_family) {
+#ifdef INET
+	case AF_INET:
+	    break;
+#endif
+	default:
+	    error = EAFNOSUPPORT;
+	    break;
+	}
+	break;
+	case SIO_RTEMS_SHOW_STATS:
+  printf ("              MRU:%-8lu", sc->sc_mru);
+  printf ("   Bytes received:%-8lu", sc->sc_stats.ppp_ibytes);
+  printf (" Packets received:%-8lu", sc->sc_stats.ppp_ipackets);
+  printf ("   Receive errors:%-8lu\n", sc->sc_stats.ppp_ierrors);
+  printf ("       Bytes sent:%-8lu", sc->sc_stats.ppp_obytes);
+  printf ("     Packets sent:%-8lu", sc->sc_stats.ppp_opackets);
+  printf ("  Transmit errors:%-8lu\n", sc->sc_stats.ppp_oerrors);
+	
+	break;
+	
+
+    case SIOCGPPPSTATS:
+	psp = &((struct ifpppstatsreq *) data)->stats;
+	bzero(psp, sizeof(*psp));
+	psp->p = sc->sc_stats;
+#if defined(VJC) && !defined(SL_NO_STATS)
+	if (sc->sc_comp) {
+	    psp->vj.vjs_packets = sc->sc_comp->sls_packets;
+	    psp->vj.vjs_compressed = sc->sc_comp->sls_compressed;
+	    psp->vj.vjs_searches = sc->sc_comp->sls_searches;
+	    psp->vj.vjs_misses = sc->sc_comp->sls_misses;
+	    psp->vj.vjs_uncompressedin = sc->sc_comp->sls_uncompressedin;
+	    psp->vj.vjs_compressedin = sc->sc_comp->sls_compressedin;
+	    psp->vj.vjs_errorin = sc->sc_comp->sls_errorin;
+	    psp->vj.vjs_tossed = sc->sc_comp->sls_tossed;
+	}
+#endif /* VJC */
+	break;
+
+#ifdef PPP_COMPRESS
+    case SIOCGPPPCSTATS:
+	pcp = &((struct ifpppcstatsreq *) data)->stats;
+	bzero(pcp, sizeof(*pcp));
+	if (sc->sc_xc_state != NULL)
+	    (*sc->sc_xcomp->comp_stat)(sc->sc_xc_state, &pcp->c);
+	if (sc->sc_rc_state != NULL)
+	    (*sc->sc_rcomp->decomp_stat)(sc->sc_rc_state, &pcp->d);
+	break;
+#endif /* PPP_COMPRESS */
+
+    default:
+	error = EINVAL;
+    }
+    splx(s);
+    return (error);
+}
+
+/*
+ * Queue a packet.  Start transmission if not active.
+ * Packet is placed in Information field of PPP frame.
+ */
+int
+pppoutput(ifp, m0, dst, rtp)
+    struct ifnet *ifp;
+    struct mbuf *m0;
+    struct sockaddr *dst;
+    struct rtentry *rtp;
+{
+    register struct ppp_softc *sc = &ppp_softc[ifp->if_unit];
+    int protocol, address, control;
+    u_char *cp;
+    int s, error;
+    struct ip *ip;
+    struct ifqueue *ifq;
+    enum NPmode mode;
+    int len;
+    struct mbuf *m;
+    if (sc->sc_devp == NULL || (ifp->if_flags & IFF_RUNNING) == 0
+	|| ((ifp->if_flags & IFF_UP) == 0 && dst->sa_family != AF_UNSPEC)) {
+	error = ENETDOWN;	/* sort of */
+	goto bad;
+    }
+
+    /*
+     * Compute PPP header.
+     */
+    m0->m_flags &= ~M_HIGHPRI;
+    switch (dst->sa_family) {
+#ifdef INET
+    case AF_INET:
+	address = PPP_ALLSTATIONS;
+	control = PPP_UI;
+	protocol = PPP_IP;
+	mode = sc->sc_npmode[NP_IP];
+
+	/*
+	 * If this packet has the "low delay" bit set in the IP header,
+	 * put it on the fastq instead.
+	 */
+	ip = mtod(m0, struct ip *);
+	if (ip->ip_tos & IPTOS_LOWDELAY)
+	    m0->m_flags |= M_HIGHPRI;
+	break;
+#endif
+    case AF_UNSPEC:
+	address = PPP_ADDRESS(dst->sa_data);
+	control = PPP_CONTROL(dst->sa_data);
+	protocol = PPP_PROTOCOL(dst->sa_data);
+	mode = NPMODE_PASS;
+	break;
+    default:
+	printf("ppp%d: af%d not supported\n", ifp->if_unit, dst->sa_family);
+	error = EAFNOSUPPORT;
+	goto bad;
+    }
+
+    /*
+     * Drop this packet, or return an error, if necessary.
+     */
+    if (mode == NPMODE_ERROR) {
+	error = ENETDOWN;
+	goto bad;
+    }
+    if (mode == NPMODE_DROP) {
+	error = 0;
+	goto bad;
+    }
+
+    /*
+     * Add PPP header.  If no space in first mbuf, allocate another.
+     * (This assumes M_LEADINGSPACE is always 0 for a cluster mbuf.)
+     */
+    if (M_LEADINGSPACE(m0) < PPP_HDRLEN) {
+	m0 = m_prepend(m0, PPP_HDRLEN, M_DONTWAIT);
+	if (m0 == 0) {
+	    error = ENOBUFS;
+	    goto bad;
+	}
+	m0->m_len = 0;
+    } else
+	m0->m_data -= PPP_HDRLEN;
+
+    cp = mtod(m0, u_char *);
+    *cp++ = address;
+    *cp++ = control;
+    *cp++ = protocol >> 8;
+    *cp++ = protocol & 0xff;
+    m0->m_len += PPP_HDRLEN;
+
+    len = 0;
+    for (m = m0; m != 0; m = m->m_next)
+	len += m->m_len;
+
+    if (sc->sc_flags & SC_LOG_OUTPKT) {
+	printf("ppp%d output: ", ifp->if_unit);
+	pppdumpm(m0);
+    }
+
+    if ((protocol & 0x8000) == 0) {
+#ifdef PPP_FILTER
+	/*
+	 * Apply the pass and active filters to the packet,
+	 * but only if it is a data packet.
+	 */
+	*mtod(m0, u_char *) = 1;	/* indicates outbound */
+	if (sc->sc_pass_filt.bf_insns != 0
+	    && bpf_filter(sc->sc_pass_filt.bf_insns, (u_char *) m0,
+			  len, 0) == 0) {
+	    error = 0;		/* drop this packet */
+	    goto bad;
+	}
+
+	/*
+	 * Update the time we sent the most recent packet.
+	 */
+	if (sc->sc_active_filt.bf_insns == 0
+	    || bpf_filter(sc->sc_active_filt.bf_insns, (u_char *) m0, len, 0))
+	    {
+	    	microtime(&ppp_time);
+	    	sc->sc_last_sent = ppp_time.tv_sec;
+	    }
+
+	*mtod(m0, u_char *) = address;
+#else
+	/*
+	 * Update the time we sent the most recent data packet.
+	 */
+  	microtime(&ppp_time);
+	sc->sc_last_sent = ppp_time.tv_sec;
+#endif /* PPP_FILTER */
+    }
+
+#if NBPFILTER > 0
+    /*
+     * See if bpf wants to look at the packet.
+     */
+    if (sc->sc_bpf)
+	bpf_mtap(sc->sc_bpf, m0);
+#endif
+
+    /*
+     * Put the packet on the appropriate queue.
+     */
+    if (mode == NPMODE_QUEUE) {
+	/* XXX we should limit the number of packets on this queue */
+	*sc->sc_npqtail = m0;
+	m0->m_nextpkt = NULL;
+	sc->sc_npqtail = &m0->m_nextpkt;
+    } else {
+	ifq = (m0->m_flags & M_HIGHPRI)? &sc->sc_fastq: &ifp->if_snd;
+	if (IF_QFULL(ifq) && dst->sa_family != AF_UNSPEC) {
+	    IF_DROP(ifq);
+	    splx(s);
+	    sc->sc_if.if_oerrors++;
+	    sc->sc_stats.ppp_oerrors++;
+	    error = ENOBUFS;
+	    goto bad;
+	}
+	IF_ENQUEUE(ifq, m0);
+	(*sc->sc_start)(sc);
+    }
+   	microtime(&ppp_time);
+    ifp->if_lastchange = ppp_time;
+    ifp->if_opackets++;
+    ifp->if_obytes += len;
+
+    return (0);
+
+bad:
+    m_freem(m0);
+    return (error);
+}
+
+/*
+ * After a change in the NPmode for some NP, move packets from the
+ * npqueue to the send queue or the fast queue as appropriate.
+ * Should be called at splsoftnet.
+ */
+static void
+ppp_requeue(sc)
+    struct ppp_softc *sc;
+{
+    struct mbuf *m, **mpp;
+    struct ifqueue *ifq;
+    enum NPmode mode;
+
+    for (mpp = &sc->sc_npqueue; (m = *mpp) != NULL; ) {
+	switch (PPP_PROTOCOL(mtod(m, u_char *))) {
+	case PPP_IP:
+	    mode = sc->sc_npmode[NP_IP];
+	    break;
+	default:
+	    mode = NPMODE_PASS;
+	}
+
+	switch (mode) {
+	case NPMODE_PASS:
+	    /*
+	     * This packet can now go on one of the queues to be sent.
+	     */
+	    *mpp = m->m_nextpkt;
+	    m->m_nextpkt = NULL;
+	    ifq = (m->m_flags & M_HIGHPRI)? &sc->sc_fastq: &sc->sc_if.if_snd;
+	    if (IF_QFULL(ifq)) {
+		IF_DROP(ifq);
+		sc->sc_if.if_oerrors++;
+		sc->sc_stats.ppp_oerrors++;
+	    } else
+		IF_ENQUEUE(ifq, m);
+	    break;
+
+	case NPMODE_DROP:
+	case NPMODE_ERROR:
+	    *mpp = m->m_nextpkt;
+	    m_freem(m);
+	    break;
+
+	case NPMODE_QUEUE:
+	    mpp = &m->m_nextpkt;
+	    break;
+	}
+    }
+    sc->sc_npqtail = mpp;
+}
+
+/*
+ * Transmitter has finished outputting some stuff;
+ * remember to call sc->sc_start later at splsoftnet.
+ */
+void
+ppp_restart(sc)
+    struct ppp_softc *sc;
+{
+
+    sc->sc_flags &= ~SC_TBUSY;
+/*    schednetisr(NETISR_PPP);
+*/}
+
+/*
+ * Get a packet to send.  This procedure is intended to be called at
+ * splsoftnet, since it may involve time-consuming operations such as
+ * applying VJ compression, packet compression, address/control and/or
+ * protocol field compression to the packet.
+ */
+struct mbuf *
+ppp_dequeue(sc)
+    struct ppp_softc *sc;
+{
+    struct mbuf *m, *mp;
+    u_char *cp;
+    int address, control, protocol;
+
+    /*
+     * Grab a packet to send: first try the fast queue, then the
+     * normal queue.
+     */
+    IF_DEQUEUE(&sc->sc_fastq, m);
+    if (m == NULL)
+	IF_DEQUEUE(&sc->sc_if.if_snd, m);
+    if (m == NULL)
+	return NULL;
+
+    ++sc->sc_stats.ppp_opackets;
+
+    /*
+     * Extract the ppp header of the new packet.
+     * The ppp header will be in one mbuf.
+     */
+    cp = mtod(m, u_char *);
+    address = PPP_ADDRESS(cp);
+    control = PPP_CONTROL(cp);
+    protocol = PPP_PROTOCOL(cp);
+
+    switch (protocol) {
+    case PPP_IP:
+#ifdef VJC
+	/*
+	 * If the packet is a TCP/IP packet, see if we can compress it.
+	 */
+	if ((sc->sc_flags & SC_COMP_TCP) && sc->sc_comp != NULL) {
+	    struct ip *ip;
+	    int type;
+
+	    mp = m;
+	    ip = (struct ip *) (cp + PPP_HDRLEN);
+	    if (mp->m_len <= PPP_HDRLEN) {
+		mp = mp->m_next;
+		if (mp == NULL)
+		    break;
+		ip = mtod(mp, struct ip *);
+	    }
+	    /* this code assumes the IP/TCP header is in one non-shared mbuf */
+	    if (ip->ip_p == IPPROTO_TCP) {
+		type = vj_compress_tcp(mp, ip, sc->sc_comp,
+				       !(sc->sc_flags & SC_NO_TCP_CCID));
+		switch (type) {
+		case TYPE_UNCOMPRESSED_TCP:
+		    protocol = PPP_VJC_UNCOMP;
+		    break;
+		case TYPE_COMPRESSED_TCP:
+		    protocol = PPP_VJC_COMP;
+		    cp = mtod(m, u_char *);
+		    cp[0] = address;	/* header has moved */
+		    cp[1] = control;
+		    cp[2] = 0;
+		    break;
+		}
+		cp[3] = protocol;	/* update protocol in PPP header */
+	    }
+	}
+#endif	/* VJC */
+	break;
+
+#ifdef PPP_COMPRESS
+    case PPP_CCP:
+	ppp_ccp(sc, m, 0);
+	break;
+#endif	/* PPP_COMPRESS */
+    }
+
+#ifdef PPP_COMPRESS
+    if (protocol != PPP_LCP && protocol != PPP_CCP
+	&& sc->sc_xc_state && (sc->sc_flags & SC_COMP_RUN)) {
+	struct mbuf *mcomp = NULL;
+	int slen, clen;
+
+	slen = 0;
+	for (mp = m; mp != NULL; mp = mp->m_next)
+	    slen += mp->m_len;
+	clen = (*sc->sc_xcomp->compress)
+	    (sc->sc_xc_state, &mcomp, m, slen, sc->sc_if.if_mtu + PPP_HDRLEN);
+	if (mcomp != NULL) {
+	    if (sc->sc_flags & SC_CCP_UP) {
+		/* Send the compressed packet instead of the original. */
+		m_freem(m);
+		m = mcomp;
+		cp = mtod(m, u_char *);
+		protocol = cp[3];
+	    } else {
+		/* Can't transmit compressed packets until CCP is up. */
+		m_freem(mcomp);
+	    }
+	}
+    }
+#endif	/* PPP_COMPRESS */
+
+    /*
+     * Compress the address/control and protocol, if possible.
+     */
+    if (sc->sc_flags & SC_COMP_AC && address == PPP_ALLSTATIONS &&
+	control == PPP_UI && protocol != PPP_ALLSTATIONS &&
+	protocol != PPP_LCP) {
+	/* can compress address/control */
+	m->m_data += 2;
+	m->m_len -= 2;
+    }
+    if (sc->sc_flags & SC_COMP_PROT && protocol < 0xFF) {
+	/* can compress protocol */
+	if (mtod(m, u_char *) == cp) {
+	    cp[2] = cp[1];	/* move address/control up */
+	    cp[1] = cp[0];
+	}
+	++m->m_data;
+	--m->m_len;
+    }
+
+    return m;
+}
+
+/*
+ * Software interrupt routine, called at splsoftnet.
+ */
+void
+pppintr()
+{
+    struct ppp_softc *sc;
+    int i, s, s2;
+    struct mbuf *m;
+
+    sc = ppp_softc;
+    for (i = 0; i < NPPP; ++i, ++sc) {
+	if (!(sc->sc_flags & SC_TBUSY)
+	    && (sc->sc_if.if_snd.ifq_head || sc->sc_fastq.ifq_head)) {
+	    s2 = splimp();
+	    sc->sc_flags |= SC_TBUSY;
+	    splx(s2);
+	    (*sc->sc_start)(sc);
+	}
+	for (;;) {
+	    IF_DEQUEUE(&sc->sc_rawq, m);
+	    if (m == NULL)
+		break;
+	    ppp_inproc(sc, m);
+	}
+    }
+}
+
+#ifdef PPP_COMPRESS
+/*
+ * Handle a CCP packet.  `rcvd' is 1 if the packet was received,
+ * 0 if it is about to be transmitted.
+ */
+static void
+ppp_ccp(sc, m, rcvd)
+    struct ppp_softc *sc;
+    struct mbuf *m;
+    int rcvd;
+{
+    u_char *dp, *ep;
+    struct mbuf *mp;
+    int slen, s;
+
+    /*
+     * Get a pointer to the data after the PPP header.
+     */
+    if (m->m_len <= PPP_HDRLEN) {
+	mp = m->m_next;
+	if (mp == NULL)
+	    return;
+	dp = (mp != NULL)? mtod(mp, u_char *): NULL;
+    } else {
+	mp = m;
+	dp = mtod(mp, u_char *) + PPP_HDRLEN;
+    }
+
+    ep = mtod(mp, u_char *) + mp->m_len;
+    if (dp + CCP_HDRLEN > ep)
+	return;
+    slen = CCP_LENGTH(dp);
+    if (dp + slen > ep) {
+	if (sc->sc_flags & SC_DEBUG)
+	    printf("if_ppp/ccp: not enough data in mbuf (%p+%x > %p+%x)\n",
+		   dp, slen, mtod(mp, u_char *), mp->m_len);
+	return;
+    }
+
+    switch (CCP_CODE(dp)) {
+    case CCP_CONFREQ:
+    case CCP_TERMREQ:
+    case CCP_TERMACK:
+	/* CCP must be going down - disable compression */
+	if (sc->sc_flags & SC_CCP_UP) {
+	    s = splimp();
+	    sc->sc_flags &= ~(SC_CCP_UP | SC_COMP_RUN | SC_DECOMP_RUN);
+	    splx(s);
+	}
+	break;
+
+    case CCP_CONFACK:
+	if (sc->sc_flags & SC_CCP_OPEN && !(sc->sc_flags & SC_CCP_UP)
+	    && slen >= CCP_HDRLEN + CCP_OPT_MINLEN
+	    && slen >= CCP_OPT_LENGTH(dp + CCP_HDRLEN) + CCP_HDRLEN) {
+	    if (!rcvd) {
+		/* we're agreeing to send compressed packets. */
+		if (sc->sc_xc_state != NULL
+		    && (*sc->sc_xcomp->comp_init)
+			(sc->sc_xc_state, dp + CCP_HDRLEN, slen - CCP_HDRLEN,
+			 sc->sc_if.if_unit, 0, sc->sc_flags & SC_DEBUG)) {
+		    s = splimp();
+		    sc->sc_flags |= SC_COMP_RUN;
+		    splx(s);
+		}
+	    } else {
+		/* peer is agreeing to send compressed packets. */
+		if (sc->sc_rc_state != NULL
+		    && (*sc->sc_rcomp->decomp_init)
+			(sc->sc_rc_state, dp + CCP_HDRLEN, slen - CCP_HDRLEN,
+			 sc->sc_if.if_unit, 0, sc->sc_mru,
+			 sc->sc_flags & SC_DEBUG)) {
+		    s = splimp();
+		    sc->sc_flags |= SC_DECOMP_RUN;
+		    sc->sc_flags &= ~(SC_DC_ERROR | SC_DC_FERROR);
+		    splx(s);
+		}
+	    }
+	}
+	break;
+
+    case CCP_RESETACK:
+	if (sc->sc_flags & SC_CCP_UP) {
+	    if (!rcvd) {
+		if (sc->sc_xc_state && (sc->sc_flags & SC_COMP_RUN))
+		    (*sc->sc_xcomp->comp_reset)(sc->sc_xc_state);
+	    } else {
+		if (sc->sc_rc_state && (sc->sc_flags & SC_DECOMP_RUN)) {
+		    (*sc->sc_rcomp->decomp_reset)(sc->sc_rc_state);
+		    s = splimp();
+		    sc->sc_flags &= ~SC_DC_ERROR;
+		    splx(s);
+		}
+	    }
+	}
+	break;
+    }
+}
+
+/*
+ * CCP is down; free (de)compressor state if necessary.
+ */
+static void
+ppp_ccp_closed(sc)
+    struct ppp_softc *sc;
+{
+    if (sc->sc_xc_state) {
+	(*sc->sc_xcomp->comp_free)(sc->sc_xc_state);
+	sc->sc_xc_state = NULL;
+    }
+    if (sc->sc_rc_state) {
+	(*sc->sc_rcomp->decomp_free)(sc->sc_rc_state);
+	sc->sc_rc_state = NULL;
+    }
+}
+#endif /* PPP_COMPRESS */
+
+/*
+ * PPP packet input routine.
+ * The caller has checked and removed the FCS and has inserted
+ * the address/control bytes and the protocol high byte if they
+ * were omitted.
+ */
+void
+ppppktin(sc, m, lost)
+    struct ppp_softc *sc;
+    struct mbuf *m;
+    int lost;
+{
+
+    if (lost)
+   	m->m_flags |= M_ERRMARK;
+    IF_ENQUEUE(&sc->sc_rawq, m);
+    pppintr();
+}
+
+/*
+ * Process a received PPP packet, doing decompression as necessary.
+ * Should be called at splsoftnet.
+ */
+#define COMPTYPE(proto)	((proto) == PPP_VJC_COMP? TYPE_COMPRESSED_TCP: \
+			 TYPE_UNCOMPRESSED_TCP)
+
+static void
+ppp_inproc(sc, m)
+    struct ppp_softc *sc;
+    struct mbuf *m;
+{
+    struct ifnet *ifp = &sc->sc_if;
+    struct ifqueue *inq;
+    int s, ilen, xlen, proto, rv;
+    u_char *cp, adrs, ctrl;
+    struct mbuf *mp, *dmp = NULL;
+    u_char *iphdr;
+    u_int hlen;
+
+    sc->sc_stats.ppp_ipackets++;
+
+    if (sc->sc_flags & SC_LOG_INPKT) {
+	ilen = 0;
+	for (mp = m; mp != NULL; mp = mp->m_next)
+	    ilen += mp->m_len;
+	printf("ppp%d: got %d bytes\n", ifp->if_unit, ilen);
+	pppdumpm(m);
+    }
+
+    cp = mtod(m, u_char *);
+    adrs = PPP_ADDRESS(cp);
+    ctrl = PPP_CONTROL(cp);
+    proto = PPP_PROTOCOL(cp);
+
+    if (m->m_flags & M_ERRMARK) {
+	m->m_flags &= ~M_ERRMARK;
+	s = splimp();
+	sc->sc_flags |= SC_VJ_RESET;
+	splx(s);
+    }
+
+#ifdef PPP_COMPRESS
+    /*
+     * Decompress this packet if necessary, update the receiver's
+     * dictionary, or take appropriate action on a CCP packet.
+     */
+    if (proto == PPP_COMP && sc->sc_rc_state && (sc->sc_flags & SC_DECOMP_RUN)
+	&& !(sc->sc_flags & SC_DC_ERROR) && !(sc->sc_flags & SC_DC_FERROR)) {
+	/* decompress this packet */
+	rv = (*sc->sc_rcomp->decompress)(sc->sc_rc_state, m, &dmp);
+	if (rv == DECOMP_OK) {
+	    m_freem(m);
+	    if (dmp == NULL) {
+		/* no error, but no decompressed packet produced */
+		return;
+	    }
+	    m = dmp;
+	    cp = mtod(m, u_char *);
+	    proto = PPP_PROTOCOL(cp);
+
+	} else {
+	    /*
+	     * An error has occurred in decompression.
+	     * Pass the compressed packet up to pppd, which may take
+	     * CCP down or issue a Reset-Req.
+	     */
+	    if (sc->sc_flags & SC_DEBUG)
+		printf("ppp%d: decompress failed %d\n", ifp->if_unit, rv);
+	    s = splimp();
+	    sc->sc_flags |= SC_VJ_RESET;
+	    if (rv == DECOMP_ERROR)
+		sc->sc_flags |= SC_DC_ERROR;
+	    else
+		sc->sc_flags |= SC_DC_FERROR;
+	    splx(s);
+	}
+
+    } else {
+	if (sc->sc_rc_state && (sc->sc_flags & SC_DECOMP_RUN)) {
+	    (*sc->sc_rcomp->incomp)(sc->sc_rc_state, m);
+	}
+	if (proto == PPP_CCP) {
+	    ppp_ccp(sc, m, 1);
+	}
+    }
+#endif
+
+    ilen = 0;
+    for (mp = m; mp != NULL; mp = mp->m_next)
+	ilen += mp->m_len;
+
+#ifdef VJC
+    if (sc->sc_flags & SC_VJ_RESET) {
+	/*
+	 * If we've missed a packet, we must toss subsequent compressed
+	 * packets which don't have an explicit connection ID.
+	 */
+	if (sc->sc_comp)
+	    vj_uncompress_tcp(NULL, 0, TYPE_ERROR, sc->sc_comp);
+	s = splimp();
+	sc->sc_flags &= ~SC_VJ_RESET;
+	splx(s);
+    }
+
+    /*
+     * See if we have a VJ-compressed packet to uncompress.
+     */
+    if (proto == PPP_VJC_COMP) {
+	if ((sc->sc_flags & SC_REJ_COMP_TCP) || sc->sc_comp == 0)
+	    goto bad;
+
+	xlen = vj_uncompress_tcp_core(cp + PPP_HDRLEN, m->m_len - PPP_HDRLEN,
+				      ilen - PPP_HDRLEN, TYPE_COMPRESSED_TCP,
+				      sc->sc_comp, &iphdr, &hlen);
+
+	if (xlen <= 0) {
+	    if (sc->sc_flags & SC_DEBUG)
+		printf("ppp%d: VJ uncompress failed on type comp\n",
+			ifp->if_unit);
+	    goto bad;
+	}
+
+	/* Copy the PPP and IP headers into a new mbuf. */
+	MGETHDR(mp, M_DONTWAIT, MT_DATA);
+	if (mp == NULL)
+	    goto bad;
+	mp->m_len = 0;
+	mp->m_next = NULL;
+	if (hlen + PPP_HDRLEN > MHLEN) {
+	    MCLGET(mp, M_DONTWAIT);
+	    if (M_TRAILINGSPACE(mp) < hlen + PPP_HDRLEN) {
+		m_freem(mp);
+		goto bad;	/* lose if big headers and no clusters */
+	    }
+	}
+	cp = mtod(mp, u_char *);
+	cp[0] = adrs;
+	cp[1] = ctrl;
+	cp[2] = 0;
+	cp[3] = PPP_IP;
+	proto = PPP_IP;
+	bcopy(iphdr, cp + PPP_HDRLEN, hlen);
+	mp->m_len = hlen + PPP_HDRLEN;
+
+	/*
+	 * Trim the PPP and VJ headers off the old mbuf
+	 * and stick the new and old mbufs together.
+	 */
+	m->m_data += PPP_HDRLEN + xlen;
+	m->m_len -= PPP_HDRLEN + xlen;
+	if (m->m_len <= M_TRAILINGSPACE(mp)) {
+	    bcopy(mtod(m, u_char *), mtod(mp, u_char *) + mp->m_len, m->m_len);
+	    mp->m_len += m->m_len;
+	    MFREE(m, mp->m_next);
+	} else
+	    mp->m_next = m;
+	m = mp;
+	ilen += hlen - xlen;
+
+    } else if (proto == PPP_VJC_UNCOMP) {
+	if ((sc->sc_flags & SC_REJ_COMP_TCP) || sc->sc_comp == 0)
+	    goto bad;
+
+	xlen = vj_uncompress_tcp_core(cp + PPP_HDRLEN, m->m_len - PPP_HDRLEN,
+				      ilen - PPP_HDRLEN, TYPE_UNCOMPRESSED_TCP,
+				      sc->sc_comp, &iphdr, &hlen);
+
+	if (xlen < 0) {
+	    if (sc->sc_flags & SC_DEBUG)
+		printf("ppp%d: VJ uncompress failed on type uncomp\n",
+			ifp->if_unit);
+	    goto bad;
+	}
+
+	proto = PPP_IP;
+	cp[3] = PPP_IP;
+    }
+#endif /* VJC */
+
+    /*
+     * If the packet will fit in a header mbuf, don't waste a
+     * whole cluster on it.
+     */
+    if (ilen <= MHLEN && M_IS_CLUSTER(m)) {
+	MGETHDR(mp, M_DONTWAIT, MT_DATA);
+	if (mp != NULL) {
+	    m_copydata(m, 0, ilen, mtod(mp, caddr_t));
+	    m_freem(m);
+	    m = mp;
+	    m->m_len = ilen;
+	}
+    }
+    m->m_pkthdr.len = ilen;
+    m->m_pkthdr.rcvif = ifp;
+
+    if ((proto & 0x8000) == 0) {
+#ifdef PPP_FILTER
+	/*
+	 * See whether we want to pass this packet, and
+	 * if it counts as link activity.
+	 */
+	adrs = *mtod(m, u_char *);	/* save address field */
+	*mtod(m, u_char *) = 0;		/* indicate inbound */
+	if (sc->sc_pass_filt.bf_insns != 0
+	    && bpf_filter(sc->sc_pass_filt.bf_insns, (u_char *) m,
+			  ilen, 0) == 0) {
+	    /* drop this packet */
+	    m_freem(m);
+	    return;
+	}
+	if (sc->sc_active_filt.bf_insns == 0
+	    || bpf_filter(sc->sc_active_filt.bf_insns, (u_char *) m, ilen, 0))
+	    {
+	    	microtime(&ppp_time);
+
+	    	sc->sc_last_recv = ppp_time.tv_sec;
+	    }
+
+	*mtod(m, u_char *) = adrs;
+#else
+	/*
+	 * Record the time that we received this packet.
+	 */
+	microtime(&ppp_time);
+	sc->sc_last_recv = ppp_time.tv_sec;
+#endif /* PPP_FILTER */
+    }
+
+#if NBPFILTER > 0
+    /* See if bpf wants to look at the packet. */
+    if (sc->sc_bpf)
+	bpf_mtap(sc->sc_bpf, m);
+#endif
+
+    rv = 0;
+    switch (proto) {
+#ifdef INET
+    case PPP_IP:
+	/*
+	 * IP packet - take off the ppp header and pass it up to IP.
+	 */
+	if ((ifp->if_flags & IFF_UP) == 0
+	    || sc->sc_npmode[NP_IP] != NPMODE_PASS) {
+	    /* interface is down - drop the packet. */
+	    m_freem(m);
+	    return;
+	}
+	m->m_pkthdr.len -= PPP_HDRLEN;
+	m->m_data += PPP_HDRLEN;
+	m->m_len -= PPP_HDRLEN;
+	schednetisr(NETISR_IP);
+	inq = &ipintrq;
+	break;
+#endif
+
+    default:
+	/*
+	 * Some other protocol - place on input queue for read().
+	 */
+	inq = &sc->sc_inq;
+	rv = 1;
+	break;
+    }
+
+    /*
+     * Put the packet on the appropriate input queue.
+     */
+    s = splimp();
+    if (IF_QFULL(inq)) {
+	IF_DROP(inq);
+	splx(s);
+	if (sc->sc_flags & SC_DEBUG)
+	    printf("ppp%d: input queue full\n", ifp->if_unit);
+	ifp->if_iqdrops++;
+	goto bad;
+    }
+    IF_ENQUEUE(inq, m);
+    splx(s);
+    ifp->if_ipackets++;
+    ifp->if_ibytes += ilen;
+	microtime(&ppp_time);
+    ifp->if_lastchange = ppp_time;
+
+    if (rv)
+	(*sc->sc_ctlp)(sc);
+
+    return;
+
+ bad:
+    m_freem(m);
+    sc->sc_if.if_ierrors++;
+    sc->sc_stats.ppp_ierrors++;
+}
+
+#define MAX_DUMP_BYTES	128
+
+static void
+pppdumpm(m0)
+    struct mbuf *m0;
+{
+    char buf[3*MAX_DUMP_BYTES+4];
+    char *bp = buf;
+    struct mbuf *m;
+    static char digits[] = "0123456789abcdef";
+
+    for (m = m0; m; m = m->m_next) {
+	int l = m->m_len;
+	u_char *rptr = (u_char *)m->m_data;
+
+	while (l--) {
+	    if (bp > buf + sizeof(buf) - 4)
+		goto done;
+	    *bp++ = digits[*rptr >> 4]; /* convert byte to ascii hex */
+	    *bp++ = digits[*rptr++ & 0xf];
+	}
+
+	if (m->m_next) {
+	    if (bp > buf + sizeof(buf) - 3)
+		goto done;
+	    *bp++ = '|';
+	} else
+	    *bp++ = ' ';
+    }
+done:
+    if (m)
+	*bp++ = '>';
+    *bp = 0;
+    printf("%s\n", buf);
+}
+
+#endif	/* NPPP > 0 */
diff --git a/c/src/libnetworking/modem/ppp.h b/c/src/libnetworking/modem/ppp.h
new file mode 100644
index 0000000000..981ca19041
--- /dev/null
+++ b/c/src/libnetworking/modem/ppp.h
@@ -0,0 +1,7 @@
+#ifndef __PPP_H__
+#define __PPP_H__
+#define NPPP 1
+#define NBPFILER 0
+#define VJC
+/*#define PPP_COMPRESS*/
+#endif
diff --git a/c/src/libnetworking/modem/ppp_tty.c b/c/src/libnetworking/modem/ppp_tty.c
new file mode 100644
index 0000000000..fc235d2686
--- /dev/null
+++ b/c/src/libnetworking/modem/ppp_tty.c
@@ -0,0 +1,1106 @@
+/*
+ * ppp_tty.c - Point-to-Point Protocol (PPP) driver for asynchronous
+ * 	       tty devices.
+ *
+ * Copyright (c) 1989 Carnegie Mellon University.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms are permitted
+ * provided that the above copyright notice and this paragraph are
+ * duplicated in all such forms and that any documentation,
+ * advertising materials, and other materials related to such
+ * distribution and use acknowledge that the software was developed
+ * by Carnegie Mellon University.  The name of the
+ * University may not be used to endorse or promote products derived
+ * from this software without specific prior written permission.
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
+ * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
+ *
+ * Drew D. Perkins
+ * Carnegie Mellon University
+ * 4910 Forbes Ave.
+ * Pittsburgh, PA 15213
+ * (412) 268-8576
+ * ddp@andrew.cmu.edu
+ *
+ * Based on:
+ *	@(#)if_sl.c	7.6.1.2 (Berkeley) 2/15/89
+ *
+ * Copyright (c) 1987 Regents of the University of California.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms are permitted
+ * provided that the above copyright notice and this paragraph are
+ * duplicated in all such forms and that any documentation,
+ * advertising materials, and other materials related to such
+ * distribution and use acknowledge that the software was developed
+ * by the University of California, Berkeley.  The name of the
+ * University may not be used to endorse or promote products derived
+ * from this software without specific prior written permission.
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
+ * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
+ *
+ * Serial Line interface
+ *
+ * Rick Adams
+ * Center for Seismic Studies
+ * 1300 N 17th Street, Suite 1450
+ * Arlington, Virginia 22209
+ * (703)276-7900
+ * rick@seismo.ARPA
+ * seismo!rick
+ *
+ * Pounded on heavily by Chris Torek (chris@mimsy.umd.edu, umcp-cs!chris).
+ * Converted to 4.3BSD Beta by Chris Torek.
+ * Other changes made at Berkeley, based in part on code by Kirk Smith.
+ *
+ * Converted to 4.3BSD+ 386BSD by Brad Parker (brad@cayman.com)
+ * Added VJ tcp header compression; more unified ioctls
+ *
+ * Extensively modified by Paul Mackerras (paulus@cs.anu.edu.au).
+ * Cleaned up a lot of the mbuf-related code to fix bugs that
+ * caused system crashes and packet corruption.  Changed pppstart
+ * so that it doesn't just give up with a "collision" if the whole
+ * packet doesn't fit in the output ring buffer.
+ *
+ * Added priority queueing for interactive IP packets, following
+ * the model of if_sl.c, plus hooks for bpf.
+ * Paul Mackerras (paulus@cs.anu.edu.au).
+ * 
+ * Adapted to RTEMS by Thomas Doerfler
+ * based on the package of Tomasz Domin delivered
+ * in RTEMS snapshot rtems-19991203:
+ *    Splitted hardware-independent driver parts from the hardware-dependent
+ *    parts, integrated into termios with newly defined line-discipline support
+ */
+
+/* Thomas: ppp_tty.c,v 1.3 2000/09/12 19:26:17 thomas Exp */
+/* $Id$ */
+/* from if_sl.c,v 1.11 84/10/04 12:54:47 rick Exp */
+/* from NetBSD: if_ppp.c,v 1.15.2.2 1994/07/28 05:17:58 cgd Exp */
+
+#include "ppp.h"
+#if NPPP > 0
+
+#define VJC
+#define PPP_COMPRESS
+
+#include <rtems/rtems_bsdnet.h> /* to get right defines */
+
+#include <sys/param.h>
+#include <sys/systm.h>
+#include <sys/proc.h>
+#include <sys/mbuf.h>
+#if 0
+#include <sys/dkstat.h>
+#endif
+#include <sys/socket.h>
+#include <sys/ioctl.h>
+#include <sys/file.h>
+#if 0
+#include <sys/tty.h>
+#endif
+#include <sys/kernel.h>
+#if 0
+#include <sys/conf.h>
+#include <sys/vnode.h>
+#endif
+
+#include <net/if.h>
+#include <net/if_types.h>
+
+#ifdef VJC
+#include <netinet/in.h>
+#include <netinet/in_systm.h>
+#include <netinet/ip.h>
+#include <net/pppcompress.h>
+#endif
+
+#include <rtems.h>
+#include <rtems/libio.h>
+#include <sys/ttycom.h>
+#include <termios.h>
+#include <termiostypes.h>
+
+#ifdef PPP_FILTER
+#include <net/bpf.h>
+#endif
+#include <net/ppp_defs.h>
+#include <net/if_ppp.h>
+#include <net/if_pppvar.h>
+
+void	pppasyncattach __P((void));
+int	pppopen   __P((struct rtems_termios_tty *tty));
+int     pppclose  __P((struct rtems_termios_tty *tty));
+int     pppread   __P((struct rtems_termios_tty *tty,
+		       rtems_libio_rw_args_t *rw_args));
+int     pppwrite  __P((struct rtems_termios_tty *tty,
+		       rtems_libio_rw_args_t *rw_args));
+int     ppptioctl __P((struct rtems_termios_tty *tty,
+		       rtems_libio_ioctl_args_t *args));
+int     pppinput  __P((int c,struct rtems_termios_tty *tty));
+int     pppstart  __P((struct rtems_termios_tty *tp));
+
+static u_short	pppfcs __P((u_short fcs, u_char *cp, int len));
+static void	pppasyncstart __P((struct ppp_softc *));
+static void	pppasyncctlp __P((struct ppp_softc *));
+static void	pppasyncrelinq __P((struct ppp_softc *));
+static void	ppp_timeout __P((void *));
+static void	pppgetm __P((struct ppp_softc *sc));
+static void	pppdumpb __P((u_char *b, int l));
+static void	ppplogchar __P((struct ppp_softc *, int));
+
+/*
+ * Some useful mbuf macros not in mbuf.h.
+ */
+#define M_IS_CLUSTER(m)	((m)->m_flags & M_EXT)
+
+#define M_DATASTART(m)	\
+	(M_IS_CLUSTER(m) ? (m)->m_ext.ext_buf : \
+	    (m)->m_flags & M_PKTHDR ? (m)->m_pktdat : (m)->m_dat)
+
+#define M_DATASIZE(m)	\
+	(M_IS_CLUSTER(m) ? (m)->m_ext.ext_size : \
+	    (m)->m_flags & M_PKTHDR ? MHLEN: MLEN)
+
+/*
+ * Does c need to be escaped?
+ */
+#define ESCAPE_P(c)	(sc->sc_asyncmap[(c) >> 5] & (1 << ((c) & 0x1F)))
+
+/*
+ * Procedures for using an async tty interface for PPP.
+ */
+
+/*
+ * compute used space in raw buffer
+ */
+#define CCOUNT(rb) (((rb).Size+(rb).Head-(rb).Tail) \
+		       % (rb).Size)
+/*
+ * compute free space in raw buffer
+ */
+#define FCOUNT(rb) ((rb).Size-CCOUNT(rb)-1)
+#define PPP_LOWAT	100	/* Process more output when < LOWAT on queue */
+#define	PPP_HIWAT	400	/* Don't start a new packet if HIWAT on que */
+/* FIXME: make dependent on raw buffer size */
+
+/*
+ * Define the PPP line discipline.
+ */
+
+static struct linesw pppdisc = {
+	pppopen, pppclose, pppread, pppwrite, 
+	pppinput, pppstart, ppptioctl, NULL
+};
+
+void
+pppasyncattach()
+{
+    linesw[PPPDISC] = pppdisc;
+}
+
+TEXT_SET(pseudo_set, pppasyncattach);
+
+/*
+ * Line specific open routine for async tty devices.
+ * Attach the given tty to the first available ppp unit.
+ * Called from device open routine or ttioctl.
+ */
+/* ARGSUSED */
+/*
+ * Open the PPP device
+ */
+int 
+pppopen(struct rtems_termios_tty *tty)
+{
+  register struct ppp_softc *sc;
+  rtems_status_code status;
+
+  if ((tty->t_line == PPPDISC)) {
+    sc = tty->t_sc;
+    if (sc != NULL && sc->sc_devp == (void *) tty) {
+      return (0);
+    }
+  }
+    
+  if ((sc = pppalloc(1)) == NULL) {
+    return 2;
+  }
+
+  if (sc->sc_relinq) {
+    (*sc->sc_relinq)(sc);	/* get previous owner to relinquish the unit */
+  }
+  /*
+   * create communication semaphore
+   */
+  status = rtems_semaphore_create (rtems_build_name ('P', 'P', 'P', 
+						     '0'+sc->sc_if.if_unit),
+				   0,
+				   RTEMS_COUNTING_SEMAPHORE,
+				   RTEMS_NO_PRIORITY_CEILING,
+				   &sc->sem_id);  
+  if (status != RTEMS_SUCCESSFUL)
+    rtems_fatal_error_occurred (status);
+
+  sc->sc_ilen = 0;
+  sc->sc_m = NULL;
+  bzero(sc->sc_asyncmap, sizeof(sc->sc_asyncmap));
+  sc->sc_asyncmap[0] = 0xffffffff;
+  sc->sc_asyncmap[3] = 0x60000000;
+  sc->sc_rasyncmap = 0;
+  sc->sc_devp = tty;
+  sc->sc_start = pppasyncstart;
+  sc->sc_ctlp = pppasyncctlp;
+  sc->sc_relinq = pppasyncrelinq;
+  sc->sc_outm = NULL;
+  pppgetm(sc);
+  sc->sc_if.if_flags |= IFF_RUNNING;
+  sc->sc_if.if_baudrate = 9600; /* FIXME: get line speed from termios */
+
+  tty->t_sc= (void *)sc;
+
+  return RTEMS_SUCCESSFUL;
+}
+ 
+/*
+ * Line specific close routine, called from device close routine
+ * and from ttioctl.
+ * Detach the tty from the ppp unit.
+ * Mimics part of ttyclose().
+ */
+int 
+pppclose(struct rtems_termios_tty *tty)
+{
+  register struct ppp_softc *sc;
+  rtems_status_code status;
+
+
+  tty->t_line = 0;
+  sc = tty->t_sc;
+  if (sc != NULL) {
+    tty->t_sc = NULL;
+    if (tty == (struct rtems_termios_tty *) sc->sc_devp) {
+      rtems_bsdnet_semaphore_obtain();
+      pppasyncrelinq(sc);
+      /*
+       * delete communication semaphore
+       */
+      status = rtems_semaphore_delete (sc->sem_id);  
+      pppdealloc(sc);
+      rtems_bsdnet_semaphore_release();
+    }
+  }
+  return RTEMS_SUCCESSFUL;
+}
+
+/*
+ * Relinquish the interface unit to another device.
+ */
+static void
+pppasyncrelinq(sc)
+    struct ppp_softc *sc;
+{
+    int s;
+
+    if (sc->sc_outm) {
+	m_freem(sc->sc_outm);
+	sc->sc_outm = NULL;
+    }
+    if (sc->sc_m) {
+	m_freem(sc->sc_m);
+	sc->sc_m = NULL;
+    }
+    if (sc->sc_flags & SC_TIMEOUT) {
+	untimeout(ppp_timeout, (void *) sc);
+	sc->sc_flags &= ~SC_TIMEOUT;
+    }
+}
+
+/*
+ * Line specific (tty) read routine.
+ */
+pppread(struct rtems_termios_tty *tty,
+	    rtems_libio_rw_args_t *rw_args)
+{
+  char *buffer;
+  int count=0,maximum;
+  rtems_status_code status;
+
+  struct mbuf *m, *m0;
+  register int s;
+  int error = 0;
+  rtems_interval    ticks;
+  register struct ppp_softc *sc = (struct ppp_softc *)tty->t_sc;
+  buffer = rw_args->buffer;
+  maximum = rw_args->count;
+
+  ticks=1000000/rtems_bsdnet_microseconds_per_tick;
+
+  if (sc == NULL) {
+    return 0;
+  }
+  /*
+   * Loop waiting for input, checking that nothing disasterous
+   * happens in the meantime.
+   */
+  for (;;) {
+    if (sc->sc_inq.ifq_head != NULL) {
+      break;
+    }
+    status=rtems_semaphore_obtain(sc->sem_id,RTEMS_WAIT,ticks);
+    if (status==RTEMS_TIMEOUT) {
+      return status;
+    }
+  }
+  rtems_bsdnet_semaphore_obtain();
+  IF_DEQUEUE(&sc->sc_inq, m0);
+  rtems_bsdnet_semaphore_release();
+
+  for (m = m0; 
+       ((m != NULL) && 
+	(count+m->m_len<maximum)); 
+       m = m->m_next) {/* check if packet will fit in buffer */
+    memcpy(buffer,mtod(m, u_char *),m->m_len);
+    count+=m->m_len;
+    buffer+=m->m_len;
+  }
+  m_freem(m0);
+  rw_args->bytes_moved = count;
+
+  return (count >= 0) ? RTEMS_SUCCESSFUL : RTEMS_UNSATISFIED;
+}
+
+/*
+ * Line specific (tty) write routine.
+ */
+int 
+pppwrite(struct rtems_termios_tty *tty,
+	  rtems_libio_rw_args_t *rw_args)
+{
+  int count,len;
+  char *out_buffer;
+  int n,maximum;
+  
+  register struct ppp_softc *sc = (struct ppp_softc *)tty->t_sc;
+  struct sockaddr dst;
+  struct mbuf *m, *m0, **mp;	
+
+  out_buffer = rw_args->buffer;
+  maximum = rw_args->count;  
+
+  rtems_bsdnet_semaphore_obtain();
+  for (mp = &m0; maximum; mp = &m->m_next) {
+    MGET(m, M_WAIT, MT_DATA);
+    if ((*mp = m) == NULL) {
+      rtems_bsdnet_semaphore_release();
+      m_freem(m0);
+      return (ENOBUFS);
+    }
+    m->m_len = 0;
+    if (maximum>= MCLBYTES / 2) {
+      MCLGET(m, M_DONTWAIT);
+    }
+    len = M_TRAILINGSPACE(m);
+    if (len > maximum) {
+      memcpy(mtod(m, u_char *),out_buffer,maximum);
+      m->m_len=maximum;
+      maximum=0;
+    }
+    else {
+      memcpy(mtod(m, u_char *),out_buffer,len);
+      maximum-=len;
+      m->m_len=len;
+      out_buffer+=len;
+    }
+  }
+  
+  dst.sa_family = AF_UNSPEC;
+  bcopy(mtod(m0, u_char *), dst.sa_data, PPP_HDRLEN);
+  m0->m_data += PPP_HDRLEN;
+  m0->m_len -= PPP_HDRLEN;
+  
+  n=pppoutput(&sc->sc_if, m0, &dst, (struct rtentry *)0);
+  rtems_bsdnet_semaphore_release();
+  return n;
+}
+
+/*
+ * Line specific (tty) ioctl routine.
+ * This discipline requires that tty device drivers call
+ * the line specific l_ioctl routine from their ioctl routines.
+ */
+/* ARGSUSED */
+int 
+ppptioctl(struct rtems_termios_tty *tty,
+	  rtems_libio_ioctl_args_t *args)
+{
+  struct ppp_softc *sc=tty->t_sc;
+  int cmd;
+  caddr_t data;
+  int error=RTEMS_SUCCESSFUL;
+
+  data=args->buffer;
+  cmd=args->command;
+
+  switch (cmd) {
+  case RTEMS_IO_GET_ATTRIBUTES:
+  case RTEMS_IO_SET_ATTRIBUTES:
+  case RTEMS_IO_TCDRAIN:
+  case TIOCGETD:	
+  case TIOCSETD:	
+    return RTEMS_UNSATISFIED;
+    break;	
+  case PPPIOCSASYNCMAP:
+    sc->sc_asyncmap[0] = *(u_int *)data;
+    break;
+
+  case PPPIOCGASYNCMAP:
+    *(u_int *)data = sc->sc_asyncmap[0];
+    break;
+    
+  case PPPIOCSRASYNCMAP:
+    sc->sc_rasyncmap = *(u_int *)data;
+    break;
+    
+  case TIOCMBIS:
+    break;
+  case TIOCMBIC:
+    break;	
+  case PPPIOCGRASYNCMAP:
+    *(u_int *)data = sc->sc_rasyncmap;
+    break;
+    
+  case PPPIOCSXASYNCMAP:
+    bcopy(data, sc->sc_asyncmap, sizeof(sc->sc_asyncmap));
+    sc->sc_asyncmap[1] = 0;		    /* mustn't escape 0x20 - 0x3f */
+    sc->sc_asyncmap[2] &= ~0x40000000;  /* mustn't escape 0x5e */
+    sc->sc_asyncmap[3] |= 0x60000000;   /* must escape 0x7d, 0x7e */
+    break;
+
+  case PPPIOCGXASYNCMAP:
+    bcopy(sc->sc_asyncmap, data, sizeof(sc->sc_asyncmap));
+    break;
+    
+  default:
+    rtems_bsdnet_semaphore_obtain();
+    error = pppioctl(sc, cmd, data, 0, NULL);
+    if (error == 0 && cmd == PPPIOCSMRU)
+      pppgetm(sc);
+    rtems_bsdnet_semaphore_release();
+	
+  }
+  return error;
+}
+
+/*
+ * FCS lookup table as calculated by genfcstab.
+ */
+static u_short fcstab[256] = {
+	0x0000,	0x1189,	0x2312,	0x329b,	0x4624,	0x57ad,	0x6536,	0x74bf,
+	0x8c48,	0x9dc1,	0xaf5a,	0xbed3,	0xca6c,	0xdbe5,	0xe97e,	0xf8f7,
+	0x1081,	0x0108,	0x3393,	0x221a,	0x56a5,	0x472c,	0x75b7,	0x643e,
+	0x9cc9,	0x8d40,	0xbfdb,	0xae52,	0xdaed,	0xcb64,	0xf9ff,	0xe876,
+	0x2102,	0x308b,	0x0210,	0x1399,	0x6726,	0x76af,	0x4434,	0x55bd,
+	0xad4a,	0xbcc3,	0x8e58,	0x9fd1,	0xeb6e,	0xfae7,	0xc87c,	0xd9f5,
+	0x3183,	0x200a,	0x1291,	0x0318,	0x77a7,	0x662e,	0x54b5,	0x453c,
+	0xbdcb,	0xac42,	0x9ed9,	0x8f50,	0xfbef,	0xea66,	0xd8fd,	0xc974,
+	0x4204,	0x538d,	0x6116,	0x709f,	0x0420,	0x15a9,	0x2732,	0x36bb,
+	0xce4c,	0xdfc5,	0xed5e,	0xfcd7,	0x8868,	0x99e1,	0xab7a,	0xbaf3,
+	0x5285,	0x430c,	0x7197,	0x601e,	0x14a1,	0x0528,	0x37b3,	0x263a,
+	0xdecd,	0xcf44,	0xfddf,	0xec56,	0x98e9,	0x8960,	0xbbfb,	0xaa72,
+	0x6306,	0x728f,	0x4014,	0x519d,	0x2522,	0x34ab,	0x0630,	0x17b9,
+	0xef4e,	0xfec7,	0xcc5c,	0xddd5,	0xa96a,	0xb8e3,	0x8a78,	0x9bf1,
+	0x7387,	0x620e,	0x5095,	0x411c,	0x35a3,	0x242a,	0x16b1,	0x0738,
+	0xffcf,	0xee46,	0xdcdd,	0xcd54,	0xb9eb,	0xa862,	0x9af9,	0x8b70,
+	0x8408,	0x9581,	0xa71a,	0xb693,	0xc22c,	0xd3a5,	0xe13e,	0xf0b7,
+	0x0840,	0x19c9,	0x2b52,	0x3adb,	0x4e64,	0x5fed,	0x6d76,	0x7cff,
+	0x9489,	0x8500,	0xb79b,	0xa612,	0xd2ad,	0xc324,	0xf1bf,	0xe036,
+	0x18c1,	0x0948,	0x3bd3,	0x2a5a,	0x5ee5,	0x4f6c,	0x7df7,	0x6c7e,
+	0xa50a,	0xb483,	0x8618,	0x9791,	0xe32e,	0xf2a7,	0xc03c,	0xd1b5,
+	0x2942,	0x38cb,	0x0a50,	0x1bd9,	0x6f66,	0x7eef,	0x4c74,	0x5dfd,
+	0xb58b,	0xa402,	0x9699,	0x8710,	0xf3af,	0xe226,	0xd0bd,	0xc134,
+	0x39c3,	0x284a,	0x1ad1,	0x0b58,	0x7fe7,	0x6e6e,	0x5cf5,	0x4d7c,
+	0xc60c,	0xd785,	0xe51e,	0xf497,	0x8028,	0x91a1,	0xa33a,	0xb2b3,
+	0x4a44,	0x5bcd,	0x6956,	0x78df,	0x0c60,	0x1de9,	0x2f72,	0x3efb,
+	0xd68d,	0xc704,	0xf59f,	0xe416,	0x90a9,	0x8120,	0xb3bb,	0xa232,
+	0x5ac5,	0x4b4c,	0x79d7,	0x685e,	0x1ce1,	0x0d68,	0x3ff3,	0x2e7a,
+	0xe70e,	0xf687,	0xc41c,	0xd595,	0xa12a,	0xb0a3,	0x8238,	0x93b1,
+	0x6b46,	0x7acf,	0x4854,	0x59dd,	0x2d62,	0x3ceb,	0x0e70,	0x1ff9,
+	0xf78f,	0xe606,	0xd49d,	0xc514,	0xb1ab,	0xa022,	0x92b9,	0x8330,
+	0x7bc7,	0x6a4e,	0x58d5,	0x495c,	0x3de3,	0x2c6a,	0x1ef1,	0x0f78
+};
+
+/*
+ * Calculate a new FCS given the current FCS and the new data.
+ */
+static u_short
+pppfcs(fcs, cp, len)
+    register u_short fcs;
+    register u_char *cp;
+    register int len;
+{
+    while (len--)
+	fcs = PPP_FCS(fcs, *cp++);
+    return (fcs);
+}
+
+/*
+ * This gets called at splsoftnet from if_ppp.c at various times
+ * when there is data ready to be sent.
+ */
+static void
+pppasyncstart(sc)
+    register struct ppp_softc *sc;
+{
+    /* Call pppstart to start output again if necessary. */
+    pppstart(sc->sc_devp);
+
+    /*
+     * This timeout is needed for operation on a pseudo-tty,
+     * because the pty code doesn't call pppstart after it has
+     * drained the t_outq.
+     */
+/*    if (!idle && (sc->sc_flags & SC_TIMEOUT) == 0) {
+	timeout(ppp_timeout, (void *) sc, 1);
+	sc->sc_flags |= SC_TIMEOUT;
+    }
+*/
+
+}
+
+
+void modem_sendpacket(struct rtems_termios_tty *tty)
+{
+  struct mbuf *l = NULL;
+  rtems_unsigned16 status;
+  int curr;
+  register struct mbuf *m;
+  register int len;
+  register u_char *start, *stop, *cp;
+  int n, ndone, done, idle;
+  struct mbuf *m2;
+  int s;
+  char c;
+   register struct ppp_softc *sc=tty->t_sc;
+  
+
+   while (CCOUNT(tty->rawOutBuf) < PPP_HIWAT) {
+	/*
+	 * See if we have an existing packet partly sent.
+	 * If not, get a new packet and start sending it.
+	 */
+	m = sc->sc_outm;
+	if (m == NULL) {
+	    /*
+	     * Get another packet to be sent.
+	     
+	     */
+	    m = ppp_dequeue(sc);
+	    if (m == NULL) 
+	    {
+	      break;
+	    }
+
+	    /*
+	     * The extra PPP_FLAG will start up a new packet, and thus
+	     * will flush any accumulated garbage.  We do this whenever
+	     * the line may have been idle for some time.
+	     */
+	    if (CCOUNT(tty->rawOutBuf) == 0) {
+	   	++sc->sc_stats.ppp_obytes;
+		c = PPP_FLAG;
+		rtems_termios_puts(&c,1,tty);
+	    }
+
+	    /* Calculate the FCS for the first mbuf's worth. */
+	    sc->sc_outfcs = pppfcs(PPP_INITFCS, mtod(m, u_char *), m->m_len);
+	    microtime(&sc->sc_if.if_lastchange);
+	}
+
+	for (;;) {
+	    start = mtod(m, u_char *);
+	    len = m->m_len;
+	    stop = start + len;
+	    while (len > 0) {
+		/*
+		 * Find out how many bytes in the string we can
+		 * handle without doing something special.
+		 */
+		for (cp = start; cp < stop; cp++)
+		    if (ESCAPE_P(*cp))
+				break;
+		n = cp - start;
+		if (n) {
+		  register int i;
+		  i = FCOUNT(tty->rawOutBuf);
+		  if (n < i) {
+		    i = n;
+		  }
+		  if (i > 0) {
+		    rtems_termios_puts(start,i,tty);
+		  }
+		  ndone = i;
+		  len -= ndone;
+		  start += ndone;
+		  sc->sc_stats.ppp_obytes += ndone;
+		  
+		  if (ndone < n)
+		    break;	/* packet doesn't fit */
+		}
+		/*
+		 * If there are characters left in the mbuf,
+		 * the first one must be special.
+		 * Put it out in a different form.
+		 */
+		if (len) {
+		    if (FCOUNT(tty->rawOutBuf) < 2) {
+			break;
+		    }
+		    else {
+		      char str[2];
+		      str[0] = PPP_ESCAPE;
+		      str[1] = *start ^ PPP_TRANS;
+		      rtems_termios_puts(str,2,tty);
+		    }
+		    sc->sc_stats.ppp_obytes += 2;
+		    start++;
+		    len--;
+		}
+	    }
+
+	    /*
+	     * If we didn't empty this mbuf, remember where we're up to.
+	     * If we emptied the last mbuf, try to add the FCS and closing
+	     * flag, and if we can't, leave sc_outm pointing to m, but with
+	     * m->m_len == 0, to remind us to output the FCS and flag later.
+	     */
+	    done = len == 0;
+	    if (done && m->m_next == NULL) {
+		u_char *p, *q;
+		int c;
+		u_char endseq[8];
+
+		/*
+		 * We may have to escape the bytes in the FCS.
+		 */
+		p = endseq;
+		c = ~sc->sc_outfcs & 0xFF;
+		if (ESCAPE_P(c)) {
+		    *p++ = PPP_ESCAPE;
+		    *p++ = c ^ PPP_TRANS;
+		} else
+		    *p++ = c;
+		c = (~sc->sc_outfcs >> 8) & 0xFF;
+		if (ESCAPE_P(c)) {
+		    *p++ = PPP_ESCAPE;
+		    *p++ = c ^ PPP_TRANS;
+		} else
+		    *p++ = c;
+		*p++ = PPP_FLAG;
+
+		/*
+		 * Try to output the FCS and flag.  If the bytes
+		 * don't all fit, back out.
+		 */
+		if (FCOUNT(tty->rawOutBuf) > (p-endseq)) {
+		  rtems_termios_puts(endseq,p-endseq,tty);
+		}
+		else {
+		  done = 0;
+		}
+		if (done)
+		    sc->sc_stats.ppp_obytes += p - endseq;
+	    }
+
+	    if (!done) {
+		/* remember where we got to */
+		m->m_data = start;
+		m->m_len = len;
+		break;
+	    }
+
+	    /* Finished with this mbuf; free it and move on. */
+	    MFREE(m, m2);
+	    m = m2;
+	    if (m == NULL) {
+		/* Finished a packet */
+		break;
+	    }
+	    sc->sc_outfcs = pppfcs(sc->sc_outfcs, mtod(m, u_char *), m->m_len);
+	}
+
+	/*
+	 * If m == NULL, we have finished a packet.
+	 * If m != NULL, we've either done as much work this time
+	 * as we need to, or else we've filled up the output queue.
+	 */
+	sc->sc_outm = m;
+	if (m)
+	    break;
+    }
+}
+
+/*
+ * This gets called when a received packet is placed on
+ * the inq, at splsoftnet.
+ */
+
+static void
+pppasyncctlp(sc)
+    struct ppp_softc *sc;
+{
+	rtems_semaphore_release(sc->sem_id);
+}
+
+/* Put data in input queue */
+int
+pppstart(struct rtems_termios_tty *tp)
+{
+  register struct ppp_softc *sc = tp->t_sc;
+
+  /*
+   * If there is stuff in the output queue, send it now.
+   * We are being called in lieu of ttstart and must do what it would.
+   */
+  sc->sc_if.if_flags  |= IFF_OACTIVE;
+  
+  /*
+   * If the transmit queue has drained and the tty has not hung up
+   * or been disconnected from the ppp unit, then tell if_ppp.c that
+   * we need more output.
+   */
+  if (CCOUNT(tp->rawOutBuf) < PPP_LOWAT
+      /*	&& !((tp->t_state & TS_CARR_ON) == 0 && (tp->t_cflag & CLOCAL) == 0)*/
+      && sc != NULL && tp == (struct rtems_termios_tty *) sc->sc_devp) {
+    modem_sendpacket(tp);
+  }
+  
+  return 0;
+}
+
+/*
+ * Timeout routine - try to start some more output.
+ */
+static void
+ppp_timeout(x)
+    void *x;
+{
+    struct rtems_termios_tty *tty = ((struct rtems_termios_tty *)x);
+    struct ppp_softc *sc = tty->t_sc;
+    struct rtems_termios_tty *tp = (struct rtems_termios_tty *) sc->sc_devp;
+    int s;
+
+    sc->sc_flags &= ~SC_TIMEOUT;
+    pppstart(tp);
+}
+
+
+/*
+ * Allocate enough mbuf to handle current MRU.
+ */
+static void
+pppgetm(sc)
+    register struct ppp_softc *sc;
+{
+    struct mbuf *m, **mp;
+    int len;
+
+    mp = &sc->sc_m;
+    for (len = sc->sc_mru + PPP_HDRLEN + PPP_FCSLEN; len > 0; ){
+	if ((m = *mp) == NULL) {
+	    MGETHDR(m, M_DONTWAIT, MT_DATA);
+	    if (m == NULL)
+		break;
+	    *mp = m;
+	    MCLGET(m, M_DONTWAIT);
+	}
+	len -= M_DATASIZE(m);
+	mp = &m->m_next;
+    }
+}
+
+/*
+ * tty interface receiver interrupt.
+ */
+static unsigned paritytab[8] = {
+    0x96696996, 0x69969669, 0x69969669, 0x96696996,
+    0x69969669, 0x96696996, 0x96696996, 0x69969669
+};
+
+
+int
+pppinput(int c,struct rtems_termios_tty *tty)
+  
+{
+    register struct ppp_softc *sc=tty->t_sc;
+    struct mbuf *m;
+    int ilen, s;
+
+    if (sc == NULL )
+	return 0;
+
+    ++sc->sc_stats.ppp_ibytes;
+
+#if 0
+    if (c & TTY_FE) {
+	/* framing error or overrun on this char - abort packet */
+	if (sc->sc_flags & SC_DEBUG)
+	    printf("ppp%d: bad char %x\n", sc->sc_if.if_unit, c);
+	goto flush;
+    }
+#endif 
+
+    c &= 0xff;
+
+    /*
+     * Handle software flow control of output.
+     */
+/*    if (tp->t_iflag & IXON) {
+	if (c == tp->t_cc[VSTOP] ) {
+	    if ((tp->t_state & TS_TTSTOP) == 0) {
+		tp->t_state |= TS_TTSTOP;
+		sccppp_stop_transmission(tp);
+	    }
+	    return 0;
+	}
+	if (c == tp->t_cc[VSTART]  ) {
+	    tp->t_state &= ~TS_TTSTOP;
+		sccppp_start_transmission(tp);
+	    return 0;
+	}
+    }
+*/
+
+    if (c & 0x80)
+	sc->sc_flags |= SC_RCV_B7_1;
+    else
+	sc->sc_flags |= SC_RCV_B7_0;
+    if (paritytab[c >> 5] & (1 << (c & 0x1F)))
+	sc->sc_flags |= SC_RCV_ODDP;
+    else
+	sc->sc_flags |= SC_RCV_EVNP;
+
+
+    if (sc->sc_flags & SC_LOG_RAWIN)
+	ppplogchar(sc, c);
+
+    if (c == PPP_FLAG) {
+	ilen = sc->sc_ilen;
+	sc->sc_ilen = 0;
+
+	if (sc->sc_rawin_count > 0) 
+	    ppplogchar(sc, -1);
+
+	/*
+	 * If SC_ESCAPED is set, then we've seen the packet
+	 * abort sequence 
+	 */
+	if (sc->sc_flags & (SC_FLUSH | SC_ESCAPED)
+	    || (ilen > 0 && sc->sc_fcs != PPP_GOODFCS)) {
+	    sc->sc_flags |= SC_PKTLOST;	/* note the dropped packet */
+	    if ((sc->sc_flags & (SC_FLUSH | SC_ESCAPED)) == 0){
+		if (sc->sc_flags & SC_DEBUG)
+		    printf("ppp%d: bad fcs %x, pkt len %d\n",
+			   sc->sc_if.if_unit, sc->sc_fcs, ilen);
+		sc->sc_if.if_ierrors++;
+		sc->sc_stats.ppp_ierrors++;
+	    } else
+		sc->sc_flags &= ~(SC_FLUSH | SC_ESCAPED);
+	    return 0;
+	}
+
+	if (ilen < PPP_HDRLEN + PPP_FCSLEN) {
+	    if (ilen) {
+		if (sc->sc_flags & SC_DEBUG)
+		    printf("ppp%d: too short (%d)\n", sc->sc_if.if_unit, ilen);
+		sc->sc_if.if_ierrors++;
+		sc->sc_stats.ppp_ierrors++;
+		sc->sc_flags |= SC_PKTLOST;
+		splx(s);
+	    }
+	    return 0;
+	}
+
+	/*
+	 * Remove FCS trailer.  Somewhat painful...
+	 */
+	ilen -= 2;
+	if (--sc->sc_mc->m_len == 0) {
+	    for (m = sc->sc_m; m->m_next != sc->sc_mc; m = m->m_next)
+		;
+	    sc->sc_mc = m;
+	}
+	sc->sc_mc->m_len--;
+
+	/* excise this mbuf chain */
+	m = sc->sc_m;
+	sc->sc_m = sc->sc_mc->m_next;
+	sc->sc_mc->m_next = NULL;
+	ppppktin(sc, m, sc->sc_flags & SC_PKTLOST);
+	if (sc->sc_flags & SC_PKTLOST) {
+	    sc->sc_flags &= ~SC_PKTLOST;
+	}
+
+	pppgetm(sc);
+	return 0;
+    }
+
+    if (sc->sc_flags & SC_FLUSH) {
+	if (sc->sc_flags & SC_LOG_FLUSH)
+	    ppplogchar(sc, c);
+	return 0;
+    }
+
+    if (c < 0x20 && (sc->sc_rasyncmap & (1 << c)))
+	return 0;
+
+    if (sc->sc_flags & SC_ESCAPED) {
+	sc->sc_flags &= ~SC_ESCAPED;
+	c ^= PPP_TRANS;
+    } else if (c == PPP_ESCAPE) {
+	sc->sc_flags |= SC_ESCAPED;
+	return 0;
+    }
+
+    /*
+     * Initialize buffer on first octet received.
+     * First octet could be address or protocol (when compressing
+     * address/control).
+     * Second octet is control.
+     * Third octet is first or second (when compressing protocol)
+     * octet of protocol.
+     * Fourth octet is second octet of protocol.
+     */
+    if (sc->sc_ilen == 0) {
+	/* reset the first input mbuf */
+	if (sc->sc_m == NULL) {
+	    pppgetm(sc);
+	    if (sc->sc_m == NULL) {
+		if (sc->sc_flags & SC_DEBUG)
+		    printf("ppp%d: no input mbufs!\n", sc->sc_if.if_unit);
+		goto flush;
+	    }
+	}
+	m = sc->sc_m;
+	m->m_len = 0;
+	m->m_data = M_DATASTART(sc->sc_m);
+	sc->sc_mc = m;
+	sc->sc_mp = mtod(m, char *);
+	sc->sc_fcs = PPP_INITFCS;
+	if (c != PPP_ALLSTATIONS) {
+	    if (sc->sc_flags & SC_REJ_COMP_AC) {
+		if (sc->sc_flags & SC_DEBUG)
+		    printf("ppp%d: garbage received: 0x%x (need 0xFF)\n",
+			   sc->sc_if.if_unit, c);
+		goto flush;
+	    }
+	    *sc->sc_mp++ = PPP_ALLSTATIONS;
+	    *sc->sc_mp++ = PPP_UI;
+	    sc->sc_ilen += 2;
+	    m->m_len += 2;
+	}
+    }
+    if (sc->sc_ilen == 1 && c != PPP_UI) {
+	if (sc->sc_flags & SC_DEBUG)
+	    printf("ppp%d: missing UI (0x3), got 0x%x\n",
+		   sc->sc_if.if_unit, c);
+	goto flush;
+    }
+    if (sc->sc_ilen == 2 && (c & 1) == 1) {
+	/* a compressed protocol */
+	*sc->sc_mp++ = 0;
+	sc->sc_ilen++;
+	sc->sc_mc->m_len++;
+    }
+    if (sc->sc_ilen == 3 && (c & 1) == 0) {
+	if (sc->sc_flags & SC_DEBUG)
+	    printf("ppp%d: bad protocol %x\n", sc->sc_if.if_unit,
+		   (sc->sc_mp[-1] << 8) + c);
+	goto flush;
+    }
+
+    /* packet beyond configured mru? */
+    if (++sc->sc_ilen > sc->sc_mru + PPP_HDRLEN + PPP_FCSLEN) {
+	if (sc->sc_flags & SC_DEBUG)
+	    printf("ppp%d: packet too big\n", sc->sc_if.if_unit);
+	goto flush;
+    }
+
+    /* is this mbuf full? */
+    m = sc->sc_mc;
+    if (M_TRAILINGSPACE(m) <= 0) {
+	if (m->m_next == NULL) {
+	    pppgetm(sc);
+	    if (m->m_next == NULL) {
+		if (sc->sc_flags & SC_DEBUG)
+		    printf("ppp%d: too few input mbufs!\n", sc->sc_if.if_unit);
+		goto flush;
+	    }
+	}
+	sc->sc_mc = m = m->m_next;
+	m->m_len = 0;
+	m->m_data = M_DATASTART(m);
+	sc->sc_mp = mtod(m, char *);
+    }
+
+    ++m->m_len;
+    *sc->sc_mp++ = c;
+    sc->sc_fcs = PPP_FCS(sc->sc_fcs, c);
+    return 0;
+
+ flush:
+    if (!(sc->sc_flags & SC_FLUSH)) {
+	sc->sc_if.if_ierrors++;
+	sc->sc_stats.ppp_ierrors++;
+	sc->sc_flags |= SC_FLUSH;
+	if (sc->sc_flags & SC_LOG_FLUSH)
+	    ppplogchar(sc, c);
+    }
+    return 0;
+}
+
+
+#define MAX_DUMP_BYTES	128
+
+static void
+ppplogchar(sc, c)
+    struct ppp_softc *sc;
+    int c;
+{
+    if (c >= 0)
+	sc->sc_rawin[sc->sc_rawin_count++] = c;
+    if (sc->sc_rawin_count >= sizeof(sc->sc_rawin)
+	|| (c < 0 && sc->sc_rawin_count > 0)) {
+	printf("ppp%d input: ", sc->sc_if.if_unit);
+	pppdumpb(sc->sc_rawin, sc->sc_rawin_count);
+	sc->sc_rawin_count = 0;
+    }
+}
+
+static void
+pppdumpb(b, l)
+    u_char *b;
+    int l;
+{
+    char buf[3*MAX_DUMP_BYTES+4];
+    char *bp = buf;
+    static char digits[] = "0123456789abcdef";
+
+    while (l--) {
+	if (bp >= buf + sizeof(buf) - 3) {
+	    *bp++ = '>';
+	    break;
+	}
+	*bp++ = digits[*b >> 4]; /* convert byte to ascii hex */
+	*bp++ = digits[*b++ & 0xf];
+	*bp++ = ' ';
+    }
+
+    *bp = 0;
+    printf("%s\n", buf);
+}
+
+#endif	/* NPPP > 0 */
diff --git a/c/src/libnetworking/modem/pppcompress.c b/c/src/libnetworking/modem/pppcompress.c
new file mode 100644
index 0000000000..a7d2734c8d
--- /dev/null
+++ b/c/src/libnetworking/modem/pppcompress.c
@@ -0,0 +1,593 @@
+/*-
+ * Copyright (c) 1989 The Regents of the University of California.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. All advertising materials mentioning features or use of this software
+ *    must display the following acknowledgement:
+ *	This product includes software developed by the University of
+ *	California, Berkeley and its contributors.
+ * 4. Neither the name of the University nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ *	@(#)slcompress.c	7.7 (Berkeley) 5/7/91
+ */
+
+/*
+ * Routines to compress and uncompess tcp packets (for transmission
+ * over low speed serial lines.
+ *
+ * Van Jacobson (van@helios.ee.lbl.gov), Dec 31, 1989:
+ *    - Initial distribution.
+ *
+ *	$Id$
+ */
+  
+#include <sys/types.h>
+#include <sys/param.h>
+#include <sys/systm.h>
+#include <sys/mbuf.h>
+#include <sys/socket.h>
+#include <sys/socketvar.h>
+
+#include <netinet/in.h>
+#include <netinet/in_systm.h>
+#include <netinet/ip.h>
+#include <netinet/tcp.h>
+
+#include <net/pppcompress.h>
+
+#ifndef SL_NO_STATS
+#define INCR(counter) ++comp->counter;
+#else
+#define INCR(counter)
+#endif
+
+#define BCMP(p1, p2, n) bcmp((char *)(p1), (char *)(p2), (int)(n))
+#define BCOPY(p1, p2, n) bcopy((char *)(p1), (char *)(p2), (int)(n))
+#ifndef KERNEL
+#define ovbcopy bcopy
+#endif
+
+void
+vj_compress_init(comp, max_state)
+	struct vjcompress *comp;
+	int max_state;
+{
+	register u_int i;
+	register struct cstate *tstate = comp->tstate;
+
+	if ((unsigned) max_state > MAX_STATES - 1)
+		max_state = MAX_STATES - 1;
+	bzero((char *)comp, sizeof(*comp));
+	for (i = max_state; i > 0; --i) {
+		tstate[i].cs_id = i;
+		tstate[i].cs_next = &tstate[i - 1];
+	}
+	tstate[0].cs_next = &tstate[max_state];
+	tstate[0].cs_id = 0;
+	comp->last_cs = &tstate[0];
+	comp->last_recv = 255;
+	comp->last_xmit = 255;
+	comp->flags = SLF_TOSS;
+}
+
+
+/* ENCODE encodes a number that is known to be non-zero.  ENCODEZ
+ * checks for zero (since zero has to be encoded in the long, 3 byte
+ * form).
+ */
+#define ENCODE(n) { \
+	if ((u_short)(n) >= 256) { \
+		*cp++ = 0; \
+		cp[1] = (n); \
+		cp[0] = (n) >> 8; \
+		cp += 2; \
+	} else { \
+		*cp++ = (n); \
+	} \
+}
+#define ENCODEZ(n) { \
+	if ((u_short)(n) >= 256 || (u_short)(n) == 0) { \
+		*cp++ = 0; \
+		cp[1] = (n); \
+		cp[0] = (n) >> 8; \
+		cp += 2; \
+	} else { \
+		*cp++ = (n); \
+	} \
+}
+
+#define DECODEL(f) { \
+	if (*cp == 0) {\
+		(f) = htonl(ntohl(f) + ((cp[1] << 8) | cp[2])); \
+		cp += 3; \
+	} else { \
+		(f) = htonl(ntohl(f) + (u_long)*cp++); \
+	} \
+}
+
+#define DECODES(f) { \
+	if (*cp == 0) {\
+		(f) = htons(ntohs(f) + ((cp[1] << 8) | cp[2])); \
+		cp += 3; \
+	} else { \
+		(f) = htons(ntohs(f) + (u_long)*cp++); \
+	} \
+}
+
+#define DECODEU(f) { \
+	if (*cp == 0) {\
+		(f) = htons((cp[1] << 8) | cp[2]); \
+		cp += 3; \
+	} else { \
+		(f) = htons((u_long)*cp++); \
+	} \
+}
+
+u_int
+vj_compress_tcp(m, ip, comp, compress_cid)
+	struct mbuf *m;
+	register struct ip *ip;
+	struct vjcompress *comp;
+	int compress_cid;
+{
+	register struct cstate *cs = comp->last_cs->cs_next;
+	register u_int hlen = ip->ip_hl;
+	register struct tcphdr *oth;
+	register struct tcphdr *th;
+	register u_int deltaS, deltaA;
+	register u_int changes = 0;
+	u_char new_seq[16];
+	register u_char *cp = new_seq;
+
+	/*
+	 * Bail if this is an IP fragment or if the TCP packet isn't
+	 * `compressible' (i.e., ACK isn't set or some other control bit is
+	 * set).  (We assume that the caller has already made sure the
+	 * packet is IP proto TCP).
+	 */
+	if ((ip->ip_off & htons(0x3fff)) || m->m_len < 40)
+		return (TYPE_IP);
+
+	th = (struct tcphdr *)&((int *)ip)[hlen];
+	if ((th->th_flags & (TH_SYN|TH_FIN|TH_RST|TH_ACK)) != TH_ACK)
+		return (TYPE_IP);
+	/*
+	 * Packet is compressible -- we're going to send either a
+	 * COMPRESSED_TCP or UNCOMPRESSED_TCP packet.  Either way we need
+	 * to locate (or create) the connection state.  Special case the
+	 * most recently used connection since it's most likely to be used
+	 * again & we don't have to do any reordering if it's used.
+	 */
+	INCR(sls_packets)
+	if (ip->ip_src.s_addr != cs->cs_ip.ip_src.s_addr ||
+	    ip->ip_dst.s_addr != cs->cs_ip.ip_dst.s_addr ||
+	    *(int *)th != ((int *)&cs->cs_ip)[cs->cs_ip.ip_hl]) {
+		/*
+		 * Wasn't the first -- search for it.
+		 *
+		 * States are kept in a circularly linked list with
+		 * last_cs pointing to the end of the list.  The
+		 * list is kept in lru order by moving a state to the
+		 * head of the list whenever it is referenced.  Since
+		 * the list is short and, empirically, the connection
+		 * we want is almost always near the front, we locate
+		 * states via linear search.  If we don't find a state
+		 * for the datagram, the oldest state is (re-)used.
+		 */
+		register struct cstate *lcs;
+		register struct cstate *lastcs = comp->last_cs;
+
+		do {
+			lcs = cs; cs = cs->cs_next;
+			INCR(sls_searches)
+			if (ip->ip_src.s_addr == cs->cs_ip.ip_src.s_addr
+			    && ip->ip_dst.s_addr == cs->cs_ip.ip_dst.s_addr
+			    && *(int *)th == ((int *)&cs->cs_ip)[cs->cs_ip.ip_hl])
+				goto found;
+		} while (cs != lastcs);
+
+		/*
+		 * Didn't find it -- re-use oldest cstate.  Send an
+		 * uncompressed packet that tells the other side what
+		 * connection number we're using for this conversation.
+		 * Note that since the state list is circular, the oldest
+		 * state points to the newest and we only need to set
+		 * last_cs to update the lru linkage.
+		 */
+		INCR(sls_misses)
+		comp->last_cs = lcs;
+		hlen += th->th_off;
+		hlen <<= 2;
+		goto uncompressed;
+
+	found:
+		/*
+		 * Found it -- move to the front on the connection list.
+		 */
+		if (cs == lastcs)
+			comp->last_cs = lcs;
+		else {
+			lcs->cs_next = cs->cs_next;
+			cs->cs_next = lastcs->cs_next;
+			lastcs->cs_next = cs;
+		}
+	}
+
+	/*
+	 * Make sure that only what we expect to change changed. The first
+	 * line of the `if' checks the IP protocol version, header length &
+	 * type of service.  The 2nd line checks the "Don't fragment" bit.
+	 * The 3rd line checks the time-to-live and protocol (the protocol
+	 * check is unnecessary but costless).  The 4th line checks the TCP
+	 * header length.  The 5th line checks IP options, if any.  The 6th
+	 * line checks TCP options, if any.  If any of these things are
+	 * different between the previous & current datagram, we send the
+	 * current datagram `uncompressed'.
+	 */
+	oth = (struct tcphdr *)&((int *)&cs->cs_ip)[hlen];
+	deltaS = hlen;
+	hlen += th->th_off;
+	hlen <<= 2;
+
+	if (((u_short *)ip)[0] != ((u_short *)&cs->cs_ip)[0] ||
+	    ((u_short *)ip)[3] != ((u_short *)&cs->cs_ip)[3] ||
+	    ((u_short *)ip)[4] != ((u_short *)&cs->cs_ip)[4] ||
+	    th->th_off != oth->th_off ||
+	    (deltaS > 5 &&
+	     BCMP(ip + 1, &cs->cs_ip + 1, (deltaS - 5) << 2)) ||
+	    (th->th_off > 5 &&
+	     BCMP(th + 1, oth + 1, (th->th_off - 5) << 2)))
+		goto uncompressed;
+
+	/*
+	 * Figure out which of the changing fields changed.  The
+	 * receiver expects changes in the order: urgent, window,
+	 * ack, seq (the order minimizes the number of temporaries
+	 * needed in this section of code).
+	 */
+	if (th->th_flags & TH_URG) {
+		deltaS = ntohs(th->th_urp);
+		ENCODEZ(deltaS);
+		changes |= NEW_U;
+	} else if (th->th_urp != oth->th_urp)
+		/* argh! URG not set but urp changed -- a sensible
+		 * implementation should never do this but RFC793
+		 * doesn't prohibit the change so we have to deal
+		 * with it. */
+		 goto uncompressed;
+
+	if (deltaS = (u_short)(ntohs(th->th_win) - ntohs(oth->th_win))) {
+		ENCODE(deltaS);
+		changes |= NEW_W;
+	}
+
+	if (deltaA = ntohl(th->th_ack) - ntohl(oth->th_ack)) {
+		if (deltaA > 0xffff)
+			goto uncompressed;
+		ENCODE(deltaA);
+		changes |= NEW_A;
+	}
+
+	if (deltaS = ntohl(th->th_seq) - ntohl(oth->th_seq)) {
+		if (deltaS > 0xffff)
+			goto uncompressed;
+		ENCODE(deltaS);
+		changes |= NEW_S;
+	}
+
+	switch(changes) {
+
+	case 0:
+		/*
+		 * Nothing changed. If this packet contains data and the
+		 * last one didn't, this is probably a data packet following
+		 * an ack (normal on an interactive connection) and we send
+		 * it compressed.  Otherwise it's probably a retransmit,
+		 * retransmitted ack or window probe.  Send it uncompressed
+		 * in case the other side missed the compressed version.
+		 */
+		if (ip->ip_len != cs->cs_ip.ip_len &&
+		    ntohs(cs->cs_ip.ip_len) == hlen)
+			break;
+
+		/* (fall through) */
+
+	case SPECIAL_I:
+	case SPECIAL_D:
+		/*
+		 * actual changes match one of our special case encodings --
+		 * send packet uncompressed.
+		 */
+		goto uncompressed;
+
+	case NEW_S|NEW_A:
+		if (deltaS == deltaA &&
+		    deltaS == ntohs(cs->cs_ip.ip_len) - hlen) {
+			/* special case for echoed terminal traffic */
+			changes = SPECIAL_I;
+			cp = new_seq;
+		}
+		break;
+
+	case NEW_S:
+		if (deltaS == ntohs(cs->cs_ip.ip_len) - hlen) {
+			/* special case for data xfer */
+			changes = SPECIAL_D;
+			cp = new_seq;
+		}
+		break;
+	}
+
+	deltaS = ntohs(ip->ip_id) - ntohs(cs->cs_ip.ip_id);
+	if (deltaS != 1) {
+		ENCODEZ(deltaS);
+		changes |= NEW_I;
+	}
+	if (th->th_flags & TH_PUSH)
+		changes |= TCP_PUSH_BIT;
+	/*
+	 * Grab the cksum before we overwrite it below.  Then update our
+	 * state with this packet's header.
+	 */
+	deltaA = ntohs(th->th_sum);
+	BCOPY(ip, &cs->cs_ip, hlen);
+
+	/*
+	 * We want to use the original packet as our compressed packet.
+	 * (cp - new_seq) is the number of bytes we need for compressed
+	 * sequence numbers.  In addition we need one byte for the change
+	 * mask, one for the connection id and two for the tcp checksum.
+	 * So, (cp - new_seq) + 4 bytes of header are needed.  hlen is how
+	 * many bytes of the original packet to toss so subtract the two to
+	 * get the new packet size.
+	 */
+	deltaS = cp - new_seq;
+	cp = (u_char *)ip;
+	if (compress_cid == 0 || comp->last_xmit != cs->cs_id) {
+		comp->last_xmit = cs->cs_id;
+		hlen -= deltaS + 4;
+		cp += hlen;
+		*cp++ = changes | NEW_C;
+		*cp++ = cs->cs_id;
+	} else {
+		hlen -= deltaS + 3;
+		cp += hlen;
+		*cp++ = changes;
+	}
+	m->m_len -= hlen;
+	m->m_data += hlen;
+	*cp++ = deltaA >> 8;
+	*cp++ = deltaA;
+	BCOPY(new_seq, cp, deltaS);
+	INCR(sls_compressed)
+	return (TYPE_COMPRESSED_TCP);
+
+	/*
+	 * Update connection state cs & send uncompressed packet ('uncompressed'
+	 * means a regular ip/tcp packet but with the 'conversation id' we hope
+	 * to use on future compressed packets in the protocol field).
+	 */
+uncompressed:
+	BCOPY(ip, &cs->cs_ip, hlen);
+	ip->ip_p = cs->cs_id;
+	comp->last_xmit = cs->cs_id;
+	return (TYPE_UNCOMPRESSED_TCP);
+}
+
+
+int
+vj_uncompress_tcp(bufp, len, type, comp)
+	u_char **bufp;
+	int len;
+	u_int type;
+	struct vjcompress *comp;
+{
+	u_char *hdr, *cp;
+	int hlen, vjlen;
+
+	cp = bufp? *bufp: NULL;
+	vjlen = vj_uncompress_tcp_core(cp, len, len, type, comp, &hdr, &hlen);
+	if (vjlen < 0)
+		return (0);	/* error */
+	if (vjlen == 0)
+		return (len);	/* was uncompressed already */
+
+	cp += vjlen;
+	len -= vjlen;
+
+	/*
+	 * At this point, cp points to the first byte of data in the
+	 * packet.  If we're not aligned on a 4-byte boundary, copy the
+	 * data down so the ip & tcp headers will be aligned.  Then back up
+	 * cp by the tcp/ip header length to make room for the reconstructed
+	 * header (we assume the packet we were handed has enough space to
+	 * prepend 128 bytes of header).
+	 */
+	if ((int)cp & 3) {
+		if (len > 0)
+			(void) ovbcopy(cp, (caddr_t)((int)cp &~ 3), len);
+		cp = (u_char *)((int)cp &~ 3);
+	}
+	cp -= hlen;
+	len += hlen;
+	BCOPY(hdr, cp, hlen);
+
+	*bufp = cp;
+	return (len);
+}
+
+/*
+ * Uncompress a packet of total length total_len.  The first buflen
+ * bytes are at buf; this must include the entire (compressed or
+ * uncompressed) TCP/IP header.  This procedure returns the length
+ * of the VJ header, with a pointer to the uncompressed IP header
+ * in *hdrp and its length in *hlenp.
+ */
+int
+vj_uncompress_tcp_core(buf, buflen, total_len, type, comp, hdrp, hlenp)
+	u_char *buf;
+	int buflen, total_len;
+	u_int type;
+	struct vjcompress *comp;
+	u_char **hdrp;
+	u_int *hlenp;
+{
+	register u_char *cp;
+	register u_int hlen, changes;
+	register struct tcphdr *th;
+	register struct cstate *cs;
+	register struct ip *ip;
+	register u_short *bp;
+	register u_int vjlen;
+
+	switch (type) {
+
+	case TYPE_UNCOMPRESSED_TCP:
+		ip = (struct ip *) buf;
+		if (ip->ip_p >= MAX_STATES)
+			goto bad;
+		cs = &comp->rstate[comp->last_recv = ip->ip_p];
+		comp->flags &=~ SLF_TOSS;
+		ip->ip_p = IPPROTO_TCP;
+		/*
+		 * Calculate the size of the TCP/IP header and make sure that
+		 * we don't overflow the space we have available for it.
+		 */
+		hlen = ip->ip_hl << 2;
+		if (hlen + sizeof(struct tcphdr) > buflen)
+			goto bad;
+		hlen += ((struct tcphdr *)&((char *)ip)[hlen])->th_off << 2;
+		if (hlen > MAX_HDR || hlen > buflen)
+			goto bad;
+		BCOPY(ip, &cs->cs_ip, hlen);
+		cs->cs_hlen = hlen;
+		INCR(sls_uncompressedin)
+		*hdrp = (u_char *) &cs->cs_ip;
+		*hlenp = hlen;
+		return (0);
+
+	default:
+		goto bad;
+
+	case TYPE_COMPRESSED_TCP:
+		break;
+	}
+	/* We've got a compressed packet. */
+	INCR(sls_compressedin)
+	cp = buf;
+	changes = *cp++;
+	if (changes & NEW_C) {
+		/* Make sure the state index is in range, then grab the state.
+		 * If we have a good state index, clear the 'discard' flag. */
+		if (*cp >= MAX_STATES)
+			goto bad;
+
+		comp->flags &=~ SLF_TOSS;
+		comp->last_recv = *cp++;
+	} else {
+		/* this packet has an implicit state index.  If we've
+		 * had a line error since the last time we got an
+		 * explicit state index, we have to toss the packet. */
+		if (comp->flags & SLF_TOSS) {
+			INCR(sls_tossed)
+			return (-1);
+		}
+	}
+	cs = &comp->rstate[comp->last_recv];
+	hlen = cs->cs_ip.ip_hl << 2;
+	th = (struct tcphdr *)&((u_char *)&cs->cs_ip)[hlen];
+	th->th_sum = htons((*cp << 8) | cp[1]);
+	cp += 2;
+	if (changes & TCP_PUSH_BIT)
+		th->th_flags |= TH_PUSH;
+	else
+		th->th_flags &=~ TH_PUSH;
+
+	switch (changes & SPECIALS_MASK) {
+	case SPECIAL_I:
+		{
+		register u_int i = ntohs(cs->cs_ip.ip_len) - cs->cs_hlen;
+		th->th_ack = htonl(ntohl(th->th_ack) + i);
+		th->th_seq = htonl(ntohl(th->th_seq) + i);
+		}
+		break;
+
+	case SPECIAL_D:
+		th->th_seq = htonl(ntohl(th->th_seq) + ntohs(cs->cs_ip.ip_len)
+				   - cs->cs_hlen);
+		break;
+
+	default:
+		if (changes & NEW_U) {
+			th->th_flags |= TH_URG;
+			DECODEU(th->th_urp)
+		} else
+			th->th_flags &=~ TH_URG;
+		if (changes & NEW_W)
+			DECODES(th->th_win)
+		if (changes & NEW_A)
+			DECODEL(th->th_ack)
+		if (changes & NEW_S)
+			DECODEL(th->th_seq)
+		break;
+	}
+	if (changes & NEW_I) {
+		DECODES(cs->cs_ip.ip_id)
+	} else
+		cs->cs_ip.ip_id = htons(ntohs(cs->cs_ip.ip_id) + 1);
+
+	/*
+	 * At this point, cp points to the first byte of data in the
+	 * packet.  Fill in the IP total length and update the IP
+	 * header checksum.
+	 */
+	vjlen = cp - buf;
+	buflen -= vjlen;
+	if (buflen < 0)
+		/* we must have dropped some characters (crc should detect
+		 * this but the old slip framing won't) */
+		goto bad;
+
+	total_len += cs->cs_hlen - vjlen;
+	cs->cs_ip.ip_len = htons(total_len);
+
+	/* recompute the ip header checksum */
+	bp = (u_short *) &cs->cs_ip;
+	cs->cs_ip.ip_sum = 0;
+	for (changes = 0; hlen > 0; hlen -= 2)
+		changes += *bp++;
+	changes = (changes & 0xffff) + (changes >> 16);
+	changes = (changes & 0xffff) + (changes >> 16);
+	cs->cs_ip.ip_sum = ~ changes;
+
+	*hdrp = (u_char *) &cs->cs_ip;
+	*hlenp = cs->cs_hlen;
+	return vjlen;
+
+bad:
+	comp->flags |= SLF_TOSS;
+	INCR(sls_errorin)
+	return (-1);
+}
diff --git a/c/src/libnetworking/net/if_pppvar.h b/c/src/libnetworking/net/if_pppvar.h
new file mode 100644
index 0000000000..6eb45a6afb
--- /dev/null
+++ b/c/src/libnetworking/net/if_pppvar.h
@@ -0,0 +1,111 @@
+/*	$Id$	*/
+/*
+ * if_pppvar.h - private structures and declarations for PPP.
+ *
+ * Copyright (c) 1994 The Australian National University.
+ * All rights reserved.
+ *
+ * Permission to use, copy, modify, and distribute this software and its
+ * documentation is hereby granted, provided that the above copyright
+ * notice appears in all copies.  This software is provided without any
+ * warranty, express or implied. The Australian National University
+ * makes no representations about the suitability of this software for
+ * any purpose.
+ *
+ * IN NO EVENT SHALL THE AUSTRALIAN NATIONAL UNIVERSITY BE LIABLE TO ANY
+ * PARTY FOR DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
+ * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN IF
+ * THE AUSTRALIAN NATIONAL UNIVERSITY HAVE BEEN ADVISED OF THE POSSIBILITY
+ * OF SUCH DAMAGE.
+ *
+ * THE AUSTRALIAN NATIONAL UNIVERSITY SPECIFICALLY DISCLAIMS ANY WARRANTIES,
+ * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
+ * AND FITNESS FOR A PARTICULAR PURPOSE.  THE SOFTWARE PROVIDED HEREUNDER IS
+ * ON AN "AS IS" BASIS, AND THE AUSTRALIAN NATIONAL UNIVERSITY HAS NO
+ * OBLIGATION TO PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS,
+ * OR MODIFICATIONS.
+ *
+ * Copyright (c) 1989 Carnegie Mellon University.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms are permitted
+ * provided that the above copyright notice and this paragraph are
+ * duplicated in all such forms and that any documentation,
+ * advertising materials, and other materials related to such
+ * distribution and use acknowledge that the software was developed
+ * by Carnegie Mellon University.  The name of the
+ * University may not be used to endorse or promote products derived
+ * from this software without specific prior written permission.
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
+ * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
+ */
+
+/*
+ * Supported network protocols.  These values are used for
+ * indexing sc_npmode.
+ */
+#define NP_IP	0		/* Internet Protocol */
+#define NUM_NP	1		/* Number of NPs. */
+
+/*
+ * Structure describing each ppp unit.
+ */
+struct ppp_softc {
+	struct	ifnet sc_if;		/* network-visible interface */
+	u_int	sc_flags;		/* control/status bits; see if_ppp.h */
+	void	*sc_devp;		/* pointer to device-dep structure */
+	void	(*sc_start) __P((struct ppp_softc *));	/* start output proc */
+	void	(*sc_ctlp) __P((struct ppp_softc *)); /* rcvd control pkt */
+	void	(*sc_relinq) __P((struct ppp_softc *)); /* relinquish ifunit */
+	short	sc_mru;			/* max receive unit */
+	pid_t	sc_xfer;		/* used in transferring unit */
+	struct	ifqueue sc_rawq;	/* received packets */
+	struct	ifqueue sc_inq;		/* queue of input packets for daemon */
+	struct	ifqueue sc_fastq;	/* interactive output packet q */
+	struct	mbuf *sc_togo;		/* output packet ready to go */
+	struct	mbuf *sc_npqueue;	/* output packets not to be sent yet */
+	struct	mbuf **sc_npqtail;	/* ptr to last next ptr in npqueue */
+	struct	pppstat sc_stats;	/* count of bytes/pkts sent/rcvd */
+	caddr_t	sc_bpf;			/* hook for BPF */
+	enum	NPmode sc_npmode[NUM_NP]; /* what to do with each NP */
+	struct	compressor *sc_xcomp;	/* transmit compressor */
+	void	*sc_xc_state;		/* transmit compressor state */
+	struct	compressor *sc_rcomp;	/* receive decompressor */
+	void	*sc_rc_state;		/* receive decompressor state */
+	time_t	sc_last_sent;		/* time (secs) last NP pkt sent */
+	time_t	sc_last_recv;		/* time (secs) last NP pkt rcvd */
+#ifdef PPP_FILTER
+	struct	bpf_program sc_pass_filt;   /* filter for packets to pass */
+	struct	bpf_program sc_active_filt; /* filter for "non-idle" packets */
+#endif /* PPP_FILTER */
+#ifdef	VJC
+	struct	vjcompress *sc_comp; 	/* vjc control buffer */
+#endif
+
+	/* Device-dependent part for async lines. */
+	ext_accm sc_asyncmap;		/* async control character map */
+	u_long	sc_rasyncmap;		/* receive async control char map */
+	struct	mbuf *sc_outm;		/* mbuf chain currently being output */
+	struct	mbuf *sc_m;		/* pointer to input mbuf chain */
+	struct	mbuf *sc_mc;		/* pointer to current input mbuf */
+	char	*sc_mp;			/* ptr to next char in input mbuf */
+	short	sc_ilen;		/* length of input packet so far */
+	u_short	sc_fcs;			/* FCS so far (input) */
+	u_short	sc_outfcs;		/* FCS so far for output packet */
+	u_char	sc_rawin[16];		/* chars as received */
+	int	sc_rawin_count;		/* # in sc_rawin */
+        rtems_id sem_id;                /* ID of comm semaphore         */
+};
+
+struct	ppp_softc ppp_softc[NPPP];
+
+struct	ppp_softc *pppalloc __P((pid_t pid));
+void	pppdealloc __P((struct ppp_softc *sc));
+int	pppoutput __P((struct ifnet *, struct mbuf *,
+		       struct sockaddr *, struct rtentry *));
+int	pppioctl __P((struct ppp_softc *sc, int cmd, caddr_t data,
+		      int flag, struct proc *p));
+void	ppp_restart __P((struct ppp_softc *sc));
+void	ppppktin __P((struct ppp_softc *sc, struct mbuf *m, int lost));
+struct	mbuf *ppp_dequeue __P((struct ppp_softc *sc));
diff --git a/c/src/libnetworking/net/pppcompress.h b/c/src/libnetworking/net/pppcompress.h
new file mode 100644
index 0000000000..3f7687e6bb
--- /dev/null
+++ b/c/src/libnetworking/net/pppcompress.h
@@ -0,0 +1,164 @@
+/*
+ * Definitions for tcp compression routines.
+ *
+ * Copyright (c) 1989 Regents of the University of California.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. All advertising materials mentioning features or use of this software
+ *    must display the following acknowledgement:
+ *	This product includes software developed by the University of
+ *	California, Berkeley and its contributors.
+ * 4. Neither the name of the University nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ *	Van Jacobson (van@helios.ee.lbl.gov), Dec 31, 1989:
+ *	- Initial distribution.
+ *
+ *	From: 	slcompress.h	7.4	90/06/28
+ *	$Id$
+ */
+
+#ifndef _NET_PPPCOMPRESS_H_
+#define _NET_PPPCOMPRESS_H_
+
+#define MAX_STATES 16		/* must be > 2 and < 256 */
+#define MAX_HDR MLEN		/* XXX 4bsd-ism: should really be 128 */
+
+/*
+ * Compressed packet format:
+ *
+ * The first octet contains the packet type (top 3 bits), TCP
+ * 'push' bit, and flags that indicate which of the 4 TCP sequence
+ * numbers have changed (bottom 5 bits).  The next octet is a
+ * conversation number that associates a saved IP/TCP header with
+ * the compressed packet.  The next two octets are the TCP checksum
+ * from the original datagram.  The next 0 to 15 octets are
+ * sequence number changes, one change per bit set in the header
+ * (there may be no changes and there are two special cases where
+ * the receiver implicitly knows what changed -- see below).
+ * 
+ * There are 5 numbers which can change (they are always inserted
+ * in the following order): TCP urgent pointer, window,
+ * acknowlegement, sequence number and IP ID.  (The urgent pointer
+ * is different from the others in that its value is sent, not the
+ * change in value.)  Since typical use of SLIP links is biased
+ * toward small packets (see comments on MTU/MSS below), changes
+ * use a variable length coding with one octet for numbers in the
+ * range 1 - 255 and 3 octets (0, MSB, LSB) for numbers in the
+ * range 256 - 65535 or 0.  (If the change in sequence number or
+ * ack is more than 65535, an uncompressed packet is sent.)
+ */
+
+/*
+ * Packet types (must not conflict with IP protocol version)
+ *
+ * The top nibble of the first octet is the packet type.  There are
+ * three possible types: IP (not proto TCP or tcp with one of the
+ * control flags set); uncompressed TCP (a normal IP/TCP packet but
+ * with the 8-bit protocol field replaced by an 8-bit connection id --
+ * this type of packet syncs the sender & receiver); and compressed
+ * TCP (described above).
+ *
+ * LSB of 4-bit field is TCP "PUSH" bit (a worthless anachronism) and
+ * is logically part of the 4-bit "changes" field that follows.  Top
+ * three bits are actual packet type.  For backward compatibility
+ * and in the interest of conserving bits, numbers are chosen so the
+ * IP protocol version number (4) which normally appears in this nibble
+ * means "IP packet".
+ */
+
+/* packet types */
+#define TYPE_IP 0x40
+#define TYPE_UNCOMPRESSED_TCP 0x70
+#define TYPE_COMPRESSED_TCP 0x80
+#define TYPE_ERROR 0x00
+
+/* Bits in first octet of compressed packet */
+#define NEW_C	0x40	/* flag bits for what changed in a packet */
+#define NEW_I	0x20
+#define NEW_S	0x08
+#define NEW_A	0x04
+#define NEW_W	0x02
+#define NEW_U	0x01
+
+/* reserved, special-case values of above */
+#define SPECIAL_I (NEW_S|NEW_W|NEW_U)		/* echoed interactive traffic */
+#define SPECIAL_D (NEW_S|NEW_A|NEW_W|NEW_U)	/* unidirectional data */
+#define SPECIALS_MASK (NEW_S|NEW_A|NEW_W|NEW_U)
+
+#define TCP_PUSH_BIT 0x10
+
+
+/*
+ * "state" data for each active tcp conversation on the wire.  This is
+ * basically a copy of the entire IP/TCP header from the last packet
+ * we saw from the conversation together with a small identifier
+ * the transmit & receive ends of the line use to locate saved header.
+ */
+struct cstate {
+	struct cstate *cs_next;	/* next most recently used cstate (xmit only) */
+	u_short cs_hlen;	/* size of hdr (receive only) */
+	u_char cs_id;		/* connection # associated with this state */
+	u_char cs_filler;
+	union {
+		char csu_hdr[MAX_HDR];
+		struct ip csu_ip;	/* ip/tcp hdr from most recent packet */
+	} slcs_u;
+};
+#define cs_ip slcs_u.csu_ip
+#define cs_hdr slcs_u.csu_hdr
+
+/*
+ * all the state data for one serial line (we need one of these
+ * per line).
+ */
+struct vjcompress {
+	struct cstate *last_cs;	/* most recently used tstate */
+	u_char last_recv;	/* last rcvd conn. id */
+	u_char last_xmit;	/* last sent conn. id */
+	u_short flags;
+#ifndef SL_NO_STATS
+	int sls_packets;	/* outbound packets */
+	int sls_compressed;	/* outbound compressed packets */
+	int sls_searches;	/* searches for connection state */
+	int sls_misses;		/* times couldn't find conn. state */
+	int sls_uncompressedin;	/* inbound uncompressed packets */
+	int sls_compressedin;	/* inbound compressed packets */
+	int sls_errorin;	/* inbound unknown type packets */
+	int sls_tossed;		/* inbound packets tossed because of error */
+#endif
+	struct cstate tstate[MAX_STATES];	/* xmit connection states */
+	struct cstate rstate[MAX_STATES];	/* receive connection states */
+};
+/* flag values */
+#define SLF_TOSS 1		/* tossing rcvd frames because of input err */
+
+void	 vj_compress_init __P((struct vjcompress *, int));
+u_int	 vj_compress_tcp __P((struct mbuf *,
+	    struct ip *, struct vjcompress *, int));
+int	 vj_uncompress_tcp __P((u_char **, int, u_int, struct vjcompress *));
+int	 vj_uncompress_tcp_core __P((u_char *, int, int, u_int,
+	    struct vjcompress *, u_char **, u_int *));
+
+#endif /* _NET_PPPCOMPRESS_H_ */
diff --git a/c/src/libnetworking/pppd/pppmain.c b/c/src/libnetworking/pppd/pppmain.c
new file mode 100644
index 0000000000..9036dfcb54
--- /dev/null
+++ b/c/src/libnetworking/pppd/pppmain.c
@@ -0,0 +1,1304 @@
+/*
+ * main.c - Point-to-Point Protocol main module
+ *
+ * Copyright (c) 1989 Carnegie Mellon University.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms are permitted
+ * provided that the above copyright notice and this paragraph are
+ * duplicated in all such forms and that any documentation,
+ * advertising materials, and other materials related to such
+ * distribution and use acknowledge that the software was developed
+ * by Carnegie Mellon University.  The name of the
+ * University may not be used to endorse or promote products derived
+ * from this software without specific prior written permission.
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
+ * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
+ */
+
+#ifndef lint
+/* static char rcsid[] = "$Id$"; */
+#endif
+
+#include <stdio.h>
+#include <ctype.h>
+/* #include <stdlib.h> */
+#include <string.h>
+#include <unistd.h>
+#include <signal.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <syslog.h>
+#include <netdb.h>
+#include <pwd.h>
+#include <sys/param.h>
+#include <sys/types.h>
+#include <sys/wait.h>
+#include <sys/time.h>
+#include <sys/resource.h>
+#include <sys/stat.h>
+#include <sys/socket.h>
+#include <rtems/rtems/tasks.h>
+#include <sys/types.h>
+#include <netinet/in.h>
+
+/* #include <stbconfig.h> */
+#include "pppd.h"
+#include "magic.h"
+#include "fsm.h"
+#include "lcp.h"
+#include "ipcp.h"
+#include "upap.h"
+#include "chap.h"
+#include "ccp.h"
+#include "pathnames.h"
+#include "patchlevel.h"
+
+#ifdef CBCP_SUPPORT
+#include "cbcp.h"
+#endif
+
+#if defined(SUNOS4)
+extern char *strerror();
+#endif
+
+#ifdef IPX_CHANGE
+#include "ipxcp.h"
+#endif							/* IPX_CHANGE */
+#ifdef AT_CHANGE
+#include "atcp.h"
+#endif
+
+void SetStatusInfo(int state, char * text, int res);
+
+/* interface vars */
+char ifname[32];				/* Interface name */
+int interfunit;					/* Interface unit number */
+
+char *progname;					/* Name of this program */
+char hostname[MAXNAMELEN] = "dcna";	/* Our hostname */
+static char default_devnam[MAXPATHLEN];		/* name of default device */
+/*static pid_t pid;	*/			/* Our pid */
+static uid_t uid;				/* Our real user-id */
+static int conn_running;		/* we have a [dis]connector running */
+
+int ttyfd = -1;					/* Serial port file descriptor */
+mode_t tty_mode = -1;			/* Original access permissions to tty */
+int baud_rate;					/* Actual bits/second for serial device */
+int hungup;						/* terminal has been hung up */
+int privileged;					/* we're running as real uid root */
+int need_holdoff;				/* need holdoff period before restarting */
+int detached;					/* have detached from terminal */
+
+int phase;						/* where the link is at */
+int kill_link;
+int open_ccp_flag;
+
+char **script_env;				/* Env. variable values for scripts */
+int s_env_nalloc;				/* # words avail at script_env */
+
+u_char outpacket_buf[PPP_MRU + PPP_HDRLEN];		/* buffer for outgoing packet */
+u_char inpacket_buf[PPP_MRU + PPP_HDRLEN];	/* buffer for incoming packet */
+
+
+
+char *no_ppp_msg = "lack of PPP\n";
+
+/* Prototypes for procedures local to this file. */
+static void cleanup(void);
+static void create_pidfile __P((void));
+static void close_tty __P((void));
+static void get_input __P((void));
+static void calltimeout __P((void));
+static struct timeval *timeleft __P((struct timeval *));
+static void holdoff_end __P((void *));
+static int device_script __P((char *[], int, int));
+static void reap_kids __P((void));
+static void pr_log __P((void *, char *,...));
+
+extern char *ttyname __P((int));
+extern char *getlogin __P((void));
+int main __P((int, char *[]));
+
+
+
+
+
+/*
+ * PPP Data Link Layer "protocol" table.
+ * One entry per supported protocol.
+ * The last entry must be NULL.
+ */
+struct protent *protocols[] =
+{
+	&lcp_protent,
+	&pap_protent,
+	&chap_protent,
+#ifdef CBCP_SUPPORT
+	&cbcp_protent,
+#endif
+	&ipcp_protent,
+	&ccp_protent,
+#ifdef IPX_CHANGE
+	&ipxcp_protent,
+#endif
+#ifdef AT_CHANGE
+	&atcp_protent,
+#endif
+	NULL
+};
+
+extern int connect_stb();
+
+
+extern int disconnect_stb();
+
+
+extern struct in_addr rtems_bsdnet_nameserver[];
+extern int rtems_bsdnet_nameserver_count;
+extern int __res_init(void);
+
+int pppdmain(argc, argv)
+int argc;
+char *argv[];
+{
+	int i;
+	struct timeval timo;
+	struct protent *protp;
+	struct stat statbuf;
+    	char t[100];
+
+
+	phase = PHASE_INITIALIZE;
+
+	strcpy(default_devnam, "/dev/modem");
+	strcpy(devnam, "/dev/modem");
+
+	script_env = NULL;
+
+/*    if (gethostname(hostname, MAXNAMELEN) < 0 ) {
+   die(1);
+   }
+ */
+	hostname[MAXNAMELEN - 1] = 0;
+
+	uid = 0;
+	privileged = uid == 0;
+
+	/*
+	 * Initialize to the standard option set, then parse, in order,
+	 * the system options file, the user's options file,
+	 * the tty's options file, and the command line arguments.
+	 */
+	for (i = 0; (protp = protocols[i]) != NULL; ++i)
+		(*protp->init) (0);
+
+
+
+#if 1
+	if (!ppp_available()) {
+		exit(1);
+	}
+#endif
+	/*
+	 * Check that the options given are valid and consistent.
+	 */
+	sys_check_options();
+	auth_check_options();
+	for (i = 0; (protp = protocols[i]) != NULL; ++i)
+		if (protp->check_options != NULL)
+			(*protp->check_options) ();
+
+	/*
+	 * If the user has specified the default device name explicitly,
+	 * pretend they hadn't.
+	 */
+	if (!default_device && strcmp(devnam, default_devnam) == 0)
+		default_device = 1;
+	if (default_device)
+		nodetach = 1;
+
+	/*
+	 * Initialize system-dependent stuff and magic number package.
+	 */
+	sys_init();
+	magic_init();
+
+	/*
+	 * Detach ourselves from the terminal, if required,
+	 * and identify who is running us.
+	 */
+
+/*
+	syslog(LOG_NOTICE, "pppd %s.%d%s started by %s, uid %d",
+	     VERSION, PATCHLEVEL, IMPLEMENTATION, p, uid);
+*/
+
+
+	for (;;) {
+#if 0 /* FIXME: how do we synchonize? */
+
+/* !!! here should be done some kind of synchronization - I did it following way ... */
+/* GlobalSystemStatus is set of different things shared between different tasks ... */
+#if 0
+/* XXX PPPConfiguration */
+	GlobalSystemStatus * volatile stat;
+	stat=LockSTBSystemParam();
+	stat->ConnectionStatus = NotConnected;
+	UnlockSTBSystemParam();
+#endif
+
+
+		while (1) {
+			rtems_event_set events;
+			int status;
+
+#if 0
+/* XXX PPPConfiguration */
+			stat=LockSTBSystemParam();
+			status=stat->WantConnection;
+			UnlockSTBSystemParam();
+			
+			if (status == Connect) break;
+#endif
+			rtems_event_receive(RTEMS_EVENT_1, RTEMS_WAIT | RTEMS_EVENT_ANY, RTEMS_NO_TIMEOUT, &events);
+		}
+#if 0
+/* XXX PPPConfiguration */
+	stat=LockSTBSystemParam();
+/* 	stat->WantConnection=DontConnect; */
+	stat->ConnectionStatus = Connecting;
+
+/* Here you can change default nameserver ... */
+	rtems_bsdnet_nameserver[0].s_addr=inet_addr(stat->DNS);
+	rtems_bsdnet_nameserver_count=1;
+	UnlockSTBSystemParam();
+#endif
+/* initialize DNS services here */
+	 SetStatusInfo(0, "Connecting...",0);
+
+	__res_init();
+#endif /* FIXME */
+		/*
+		 * Open the serial device and set it up to be the ppp interface.
+		 * First we open it in non-blocking mode so we can set the
+		 * various termios flags appropriately.  If we aren't dialling
+		 * out and we want to use the modem lines, we reopen it later
+		 * in order to wait for the carrier detect signal from the modem.
+		 */
+		while ((ttyfd = open(devnam, O_NONBLOCK | O_RDWR, 0)) < 0) {
+			if (errno != EINTR)
+				syslog(LOG_ERR, "Failed to open %s: %m", devnam);
+
+			if (!persist || errno != EINTR)
+				goto fail;
+		}
+
+		hungup = 0;
+		kill_link = 0;
+
+		/*
+		 * Do the equivalent of `mesg n' to stop broadcast messages.
+		 */
+		tty_mode = statbuf.st_mode;
+
+		/* run connection script */
+		/*
+		 * Set line speed, flow control, etc.
+		 * On most systems we set CLOCAL for now so that we can talk
+		 * to the modem before carrier comes up.  But this has the
+		 * side effect that we might miss it if CD drops before we
+		 * get to clear CLOCAL below.  On systems where we can talk
+		 * successfully to the modem with CLOCAL clear and CD down,
+		 * we can clear CLOCAL at this point.
+		 */
+		set_up_tty(ttyfd, 1);
+
+		/* drop dtr to hang up in case modem is off hook */
+		setdtr(ttyfd, FALSE);
+		sleep(1);
+		setdtr(ttyfd, TRUE);
+	    {
+/* Make a call ... */
+#if 0
+/* XXX PPPConfiguration */
+	    	char t[100];
+			stat=LockSTBSystemParam();
+			sprintf(t,"Dzwonię pod numer %s ...",stat->Phone_Number);
+			UnlockSTBSystemParam();	    	
+	    	SetStatusInfo(0, t,0);
+#endif
+	    }
+	    
+
+		if ((i=connect_script(ttyfd)) >0) {
+#if 0
+/* here go error messages ... */
+		static char *error_msgs[]={ "Bad script", "IO Error"
+		 	"Timeout", "Busy", "No dialtone", "No carrier",
+			"No answer", "No answer from server" };
+			setdtr(ttyfd, FALSE);
+	    	sprintf(t,"Communication error: %s",error_msgs[i-1]);
+		syslog(LOG_ERR, "Connect script failed");
+	    	SetStatusInfo(0, t,1);
+#endif
+			goto fail;
+		}
+	
+		else
+		if (i<0)
+		{
+#if 0
+	    	char t[100];
+			sprintf(t,"Łączenie z Internetem z prędkoscią %d baud...",-i);
+		    SetStatusInfo(0, t,0);
+#endif
+		}
+		else
+		{
+#if 0
+			    SetStatusInfo(0, "Łączenie z Internetem...",0);
+#endif
+		}
+		syslog(LOG_INFO, "Serial connection established.");
+
+		sleep(1);				/* give it time to set up its terminal */
+
+		/* set line speed, flow control, etc.; clear CLOCAL if modem option */
+		set_up_tty(ttyfd, 0);
+
+		/* reopen tty if necessary to wait for carrier */
+
+		/* run welcome script, if any */
+/*  if (welcomer && welcomer[0]) {
+   if (device_script(welcomer, 21, ttyfd) < 0)
+   syslog(LOG_WARNING, "Welcome script failed");
+   }
+ */
+		/* set up the serial device as a ppp interface */
+		establish_ppp(ttyfd);
+
+/*  syslog(LOG_INFO, "Using interface ppp%d", interfunit);  */
+		(void) sprintf(ifname, "ppp%d", interfunit);
+
+		/*
+		 * Start opening the connection and wait for
+		 * incoming events (reply, timeout, etc.).
+		 */
+/*   syslog(LOG_NOTICE, "Connect: %s <--> %s", ifname, devnam); */
+
+		rtems_bsdnet_semaphore_obtain();
+
+		lcp_lowerup(0);
+		lcp_open(0);			/* Start protocol */
+
+		rtems_bsdnet_semaphore_release();
+#if 0
+        SetStatusInfo(0, "Połączenie z Internetem nawiązane.",1);
+#endif
+		for (phase = PHASE_ESTABLISH; phase != PHASE_DEAD;) {
+#if 0
+			wait_input(timeleft(&timo));
+#endif
+			calltimeout();
+			get_input();
+#if 0
+/* XXX PPPConfiguration */
+			stat=LockSTBSystemParam();
+			if (stat->WantConnection==DontConnect) {
+				stat->ConnectionStatus = NotConnected;
+			    SetStatusInfo(0, "Rozłączam się ...",0);
+				lcp_close(0, "");
+				kill_link = 0;
+			}
+			UnlockSTBSystemParam();
+#endif
+			if (open_ccp_flag) {
+				if (phase == PHASE_NETWORK) {
+					ccp_fsm[0].flags = OPT_RESTART;		/* clears OPT_SILENT */
+					(*ccp_protent.open) (0);
+				}
+				open_ccp_flag = 0;
+			}
+		}
+		/*
+		 * If we may want to bring the link up again, transfer
+		 * the ppp unit back to the loopback.  Set the
+		 * real serial device back to its normal mode of operation.
+		 */
+		clean_check();
+		disestablish_ppp(ttyfd);
+#if 0
+	    SetStatusInfo(0, "Połączenie z Internetem zerwane.",1);
+#endif
+		/*
+		 * Run disconnector script, if requested.
+		 * XXX we may not be able to do this if the line has hung up!
+		 */
+/*  if (disconnector && !hungup) {
+   set_up_tty(ttyfd, 1);
+   if (device_script(disconnector, ttyfd, ttyfd) < 0) {
+   syslog(LOG_WARNING, "disconnect script failed");
+   } else {
+   syslog(LOG_INFO, "Serial link disconnected.");
+   }
+   }
+ */
+	  fail:
+#if 0
+/* XXX PPPConfiguration */
+		stat=LockSTBSystemParam();
+		stat->ConnectionStatus = NotConnected;
+		stat->WantConnection=DontConnect;
+		UnlockSTBSystemParam();
+#endif
+		if (ttyfd >= 0)
+			close_tty();
+
+
+
+	}
+
+	return 0;
+}
+
+/*
+ * detach - detach us from the controlling terminal.
+ */
+void detach()
+{
+}
+
+/*
+ * holdoff_end - called via a timeout when the holdoff period ends.
+ */
+
+static void holdoff_end(arg)
+void *arg;
+{
+	phase = PHASE_DORMANT;
+}
+
+/*
+ * get_input - called when incoming data is available.
+ */
+static void get_input()
+{
+	int len, i;
+	u_char *p;
+	u_short protocol;
+	struct protent *protp;
+
+	p = inpacket_buf;			/* point to beginning of packet buffer */
+
+	len = read_packet(inpacket_buf);
+	if (len < 0)
+		return;
+
+	if (len == 0) {
+#if 0
+/* XXX PPPConfiguration */
+		GlobalSystemStatus * volatile stat;
+#endif
+/*   syslog(LOG_NOTICE, "Modem hangup"); */
+		hungup = 1;
+#if 0
+/* XXX PPPConfiguration */
+		stat=LockSTBSystemParam();
+		stat->ConnectionStatus = NotConnected;
+		UnlockSTBSystemParam();
+#endif
+
+		lcp_lowerdown(0);		/* serial link is no longer available */
+		link_terminated(0);
+		return;
+	}
+/*	if ((debug))
+		log_packet(p, len, "rcvd ", LOG_DEBUG);
+*/
+
+	if (len < PPP_HDRLEN) {
+/*
+		if (debug)
+			MAINDEBUG((LOG_INFO, "io(): Received short packet."));
+*/
+		return;
+	}
+/* We need to modify internal network structures here */
+	rtems_bsdnet_semaphore_obtain();
+
+	p += 2;						/* Skip address and control */
+	GETSHORT(protocol, p);
+	len -= PPP_HDRLEN;
+
+	/*
+	 * Toss all non-LCP packets unless LCP is OPEN.
+	 */
+	if (protocol != PPP_LCP && lcp_fsm[0].state != OPENED) {
+		MAINDEBUG((LOG_INFO,
+			   "get_input: Received non-LCP packet when LCP not open."));
+		rtems_bsdnet_semaphore_release();
+		return;
+	}
+	/*
+	 * Until we get past the authentication phase, toss all packets
+	 * except LCP, LQR and authentication packets.
+	 */
+	if (phase <= PHASE_AUTHENTICATE
+		&& !(protocol == PPP_LCP || protocol == PPP_LQR
+			 || protocol == PPP_PAP || protocol == PPP_CHAP)) {
+
+		rtems_bsdnet_semaphore_release();
+		return;
+	}
+	/*
+	 * Upcall the proper protocol input routine.
+	 */
+	for (i = 0; (protp = protocols[i]) != NULL; ++i) {
+		if (protp->protocol == protocol && protp->enabled_flag) {
+			(*protp->input) (0, p, len);
+			rtems_bsdnet_semaphore_release();
+			return;
+		}
+		if (protocol == (protp->protocol & ~0x8000) && protp->enabled_flag
+			&& protp->datainput != NULL) {
+			(*protp->datainput) (0, p, len);
+			rtems_bsdnet_semaphore_release();
+			return;
+		}
+	}
+
+	lcp_sprotrej(0, p - PPP_HDRLEN, len + PPP_HDRLEN);
+	rtems_bsdnet_semaphore_release();
+}
+
+
+/*
+ * quit - Clean up state and exit (with an error indication).
+ */
+void quit()
+{
+	die(1);
+}
+
+/*
+ * die - like quit, except we can specify an exit status.
+ */
+void die(status)
+int status;
+{
+	cleanup();
+}
+
+/*
+ * cleanup - restore anything which needs to be restored before we exit
+ */
+/* ARGSUSED */
+static void cleanup()
+{
+	sys_cleanup();
+
+	if (ttyfd >= 0)
+		close_tty();
+
+}
+
+/*
+ * close_tty - restore the terminal device and close it.
+ */
+static void close_tty()
+{
+	disestablish_ppp(ttyfd);
+
+	/* drop dtr to hang up */
+	setdtr(ttyfd, FALSE);
+	/*
+	 * This sleep is in case the serial port has CLOCAL set by default,
+	 * and consequently will reassert DTR when we close the device.
+	 */
+	sleep(1);
+
+	restore_tty(ttyfd);
+	close(ttyfd);
+	ttyfd = -1;
+}
+
+
+struct callout {
+	struct timeval c_time;
+	void *c_arg;
+	void (*c_func) __P((void *));
+	struct callout *c_next;
+};
+
+static struct callout *callout = NULL;
+static struct timeval timenow;
+
+/*
+ * timeout - Schedule a timeout.
+ *
+ * Note that this timeout takes the number of seconds, NOT hz (as in
+ * the kernel).
+ */
+void my_timeout(func, arg, time)
+void (*func) __P((void *));
+void *arg;
+int time;
+{
+	struct callout *newp, *p, **pp;
+
+	MAINDEBUG((LOG_DEBUG, "Timeout %lx:%lx in %d seconds.",
+			   (long) func, (long) arg, time));
+	/*
+	 * Allocate timeout.
+	 */
+	if ((newp = (struct callout *) malloc(sizeof(struct callout))) == NULL) {
+/*  syslog(LOG_ERR, "Out of memory in timeout()!"); */
+		die(1);
+	}
+	newp->c_arg = arg;
+	newp->c_func = func;
+	gettimeofday(&timenow, NULL);
+	newp->c_time.tv_sec = timenow.tv_sec + time;
+	newp->c_time.tv_usec = timenow.tv_usec;
+	/*
+	 * Find correct place and link it in.
+	 */
+	for (pp = &callout; (p = *pp); pp = &p->c_next)
+		if (newp->c_time.tv_sec < p->c_time.tv_sec
+			|| (newp->c_time.tv_sec == p->c_time.tv_sec
+				&& newp->c_time.tv_usec < p->c_time.tv_sec))
+			break;
+	newp->c_next = p;
+	*pp = newp;
+}
+
+/*
+ * untimeout - Unschedule a timeout.
+ */
+
+void untimeout(func, arg)
+void (*func) __P((void *));
+void *arg;
+{
+	struct callout **copp, *freep;
+
+	MAINDEBUG((LOG_DEBUG, "Untimeout %lx:%lx.", (long) func, (long) arg));
+
+	for (copp = &callout; (freep = *copp); copp = &freep->c_next)
+		if (freep->c_func == func && freep->c_arg == arg) {
+			*copp = freep->c_next;
+			(void) free((char *) freep);
+			break;
+		}
+}
+
+
+/*
+ * calltimeout - Call any timeout routines which are now due.
+ */
+static void calltimeout()
+{
+	struct callout *p;
+
+	while (callout != NULL) {
+		p = callout;
+
+		if (gettimeofday(&timenow, NULL) < 0) {
+			die(1);
+		}
+		if (!(p->c_time.tv_sec < timenow.tv_sec
+			  || (p->c_time.tv_sec == timenow.tv_sec
+				  && p->c_time.tv_usec <= timenow.tv_usec)))
+			break;				/* no, it's not time yet */
+
+		callout = p->c_next;
+		(*p->c_func) (p->c_arg);
+
+		free((char *) p);
+	}
+}
+
+
+/*
+ * timeleft - return the length of time until the next timeout is due.
+ */
+static struct timeval *
+ timeleft(tvp)
+struct timeval *tvp;
+{
+	if (callout == NULL)
+		return NULL;
+
+	gettimeofday(&timenow, NULL);
+	tvp->tv_sec = callout->c_time.tv_sec - timenow.tv_sec;
+	tvp->tv_usec = callout->c_time.tv_usec - timenow.tv_usec;
+	if (tvp->tv_usec < 0) {
+		tvp->tv_usec += 1000000;
+		tvp->tv_sec -= 1;
+	}
+	if (tvp->tv_sec < 0)
+		tvp->tv_sec = tvp->tv_usec = 0;
+
+	return tvp;
+}
+
+
+/*
+ * term - Catch SIGTERM signal and SIGINT signal (^C/del).
+ *
+ * Indicates that we should initiate a graceful disconnect and exit.
+ */
+static void term(sig)
+int sig;
+{
+	/*    persist = 0; *//* don't try to restart */
+	kill_link = 1;
+}
+
+static int input_fd, output_fd;
+#include <rtems/rtems/tasks.h>
+
+
+
+int modem_fd; /* FIXME: should not be global... */
+int connect_script(int fd)
+{
+	int status;
+#if 0 /* FIXME: This is WinNT special */
+	char program[256] = "TIMEOUT@10@@CLIENT@CLIENTSERVER";
+#else
+	char program[256] = { 0 };
+#endif
+#if 0
+/* XXX PPPConfiguration */
+	GlobalSystemStatus * volatile stat;
+#endif
+/* Connect scripts are almost the same as in Linux Chat ... */
+	static char *scripts[] =
+	{
+		"TIMEOUT@5@@\rAT@OK-+++\\c-OK@ATH0@TIMEOUT@90@OK@ATDT%s@CONNECT@",
+		"TIMEOUT@5@@\rAT@OK-+++\\c-OK@ATH0@TIMEOUT@90@OK@ATDT%s@CONNECT@@ppp@@Username:@%s@Password:@%s@"
+	};
+	modem_fd = fd;
+#if 0
+/* XXX PPPConfiguration */
+	stat=LockSTBSystemParam();	
+	if (strcmp("",stat->PPP_User))
+	{
+		stat->provider=Poland_TPSA;
+	}
+	else
+		stat->provider=DumbLogin;
+	switch (stat->provider) {
+	case Poland_TPSA:
+		sprintf(program, scripts[1], stat->Phone_Number, stat->PPP_User, stat->PPP_Password);
+		break;
+	default:
+		sprintf(program, scripts[0], stat->Phone_Number);
+
+	}
+	UnlockSTBSystemParam();
+#endif
+	conn_running = 0;
+
+	return chatmain(program);
+}
+
+
+/*
+ * run-program - execute a program with given arguments,
+ * but don't wait for it.
+ * If the program can't be executed, logs an error unless
+ * must_exist is 0 and the program file doesn't exist.
+ */
+int run_program(prog, args, must_exist)
+char *prog;
+char **args;
+int must_exist;
+{
+
+	return 0;
+}
+
+
+/*
+ * reap_kids - get status from any dead child processes,
+ * and log a message for abnormal terminations.
+ */
+static void reap_kids()
+{
+}
+
+
+/*
+ * log_packet - format a packet and log it.
+ */
+
+char line[256];
+char *linep;
+
+/*#define log_packet(p, len, prefix, level) */
+void log_packet(p, len, prefix, level)
+u_char *p;
+int len;
+char *prefix;
+int level;
+{
+	strcpy(line, prefix);
+	linep = line + strlen(line);
+/*	format_packet(p, len, pr_log, NULL); */
+/*    if (linep != line)
+   syslog(level, "%s", line);
+ */
+}
+
+/*
+ * format_packet - make a readable representation of a packet,
+ * calling `printer(arg, format, ...)' to output it.
+ */
+/*#define format_packet(p, len, printer, arg) */
+
+void format_packet(p, len, printer, arg)
+u_char *p;
+int len;
+void (*printer) __P((void *, char *,...));
+void *arg;
+{
+/*
+	int i, n;
+	u_short proto;
+	struct protent *protp;
+
+	if (len >= PPP_HDRLEN && p[0] == PPP_ALLSTATIONS && p[1] == PPP_UI) {
+		p += 2;
+		GETSHORT(proto, p);
+		len -= PPP_HDRLEN;
+		for (i = 0; (protp = protocols[i]) != NULL; ++i)
+			if (proto == protp->protocol)
+				break;
+		if (protp != NULL) {
+			printer(arg, "[%s", protp->name);
+			n = (*protp->printpkt) (p, len, printer, arg);
+			printer(arg, "]");
+			p += n;
+			len -= n;
+		} else {
+			printer(arg, "[proto=0x%x]", proto);
+		}
+	}
+*/
+/*    for (; len > 0; --len) {
+   GETCHAR(x, p);
+   printer(arg, " %.2x", x);
+   }
+ */
+}
+
+
+
+static void
+pr_log __V((void *arg, char *fmt,...))
+{
+	int n;
+	va_list pvar;
+	char buf[256];
+
+#if __STDC__
+	va_start(pvar, fmt);
+#else
+	void *arg;
+	char *fmt;
+	va_start(pvar);
+	arg = va_arg(pvar, void *);
+	fmt = va_arg(pvar, char *);
+#endif
+
+	n = vfmtmsg(buf, sizeof(buf), fmt, pvar);
+	va_end(pvar);
+
+	if (linep + n + 1 > line + sizeof(line)) {
+/*  syslog(LOG_DEBUG, "%s", line); */
+		linep = line;
+	}
+	strcpy(linep, buf);
+	linep += n;
+}
+
+/*
+ * print_string - print a readable representation of a string using
+ * printer.
+ */
+/*#define print_string(p, len, printer, arg) */
+
+void print_string(p, len, printer, arg)
+char *p;
+int len;
+void (*printer) __P((void *, char *,...));
+void *arg;
+{
+	int c;
+
+	printer(arg, "\"");
+	for (; len > 0; --len) {
+		c = *p++;
+		if (' ' <= c && c <= '~') {
+			if (c == '\\' || c == '"')
+				printer(arg, "\\");
+			printer(arg, "%c", c);
+		} else {
+			switch (c) {
+			case '\n':
+				printer(arg, "\\n");
+				break;
+			case '\r':
+				printer(arg, "\\r");
+				break;
+			case '\t':
+				printer(arg, "\\t");
+				break;
+			default:
+				printer(arg, "\\%.3o", c);
+			}
+		}
+	}
+	printer(arg, "\"");
+}
+
+
+/*
+ * novm - log an error message saying we ran out of memory, and die.
+ */
+void novm(msg)
+char *msg;
+{
+/*    syslog(LOG_ERR, "Virtual memory exhausted allocating %s\n", msg);
+ */ die(1);
+}
+
+/*
+ * fmtmsg - format a message into a buffer.  Like sprintf except we
+ * also specify the length of the output buffer, and we handle
+ * %r (recursive format), %m (error message) and %I (IP address) formats.
+ * Doesn't do floating-point formats.
+ * Returns the number of chars put into buf.
+ */
+int
+fmtmsg __V((char *buf, int buflen, char *fmt,...))
+{
+	va_list args;
+	int n;
+
+#if __STDC__
+	va_start(args, fmt);
+#else
+	char *buf;
+	int buflen;
+	char *fmt;
+	va_start(args);
+	buf = va_arg(args, char *);
+	buflen = va_arg(args, int);
+	fmt = va_arg(args, char *);
+#endif
+	n = vfmtmsg(buf, buflen, fmt, args);
+	va_end(args);
+	return n;
+}
+
+/*
+ * vfmtmsg - like fmtmsg, takes a va_list instead of a list of args.
+ */
+#define OUTCHAR(c)	(buflen > 0? (--buflen, *buf++ = (c)): 0)
+/*#define vfmtmsg(buf, buflen, fmt, args) */
+
+int vfmtmsg(buf, buflen, fmt, args)
+char *buf;
+int buflen;
+char *fmt;
+va_list args;
+{
+/*    int c, i, n;
+   int width, prec, fillch;
+   int base, len, neg, quoted;
+   unsigned long val = 0;
+   char *str, *f, *buf0;
+   unsigned char *p;
+   char num[32];
+   time_t t;
+   static char hexchars[] = "0123456789abcdef";
+
+   buf0 = buf;
+   --buflen;
+   while (buflen > 0) {
+   for (f = fmt; *f != '%' && *f != 0; ++f)
+   ;
+   if (f > fmt) {
+   len = f - fmt;
+   if (len > buflen)
+   len = buflen;
+   memcpy(buf, fmt, len);
+   buf += len;
+   buflen -= len;
+   fmt = f;
+   }
+   if (*fmt == 0)
+   break;
+   c = *++fmt;
+   width = prec = 0;
+   fillch = ' ';
+   if (c == '0') {
+   fillch = '0';
+   c = *++fmt;
+   }
+   if (c == '*') {
+   width = va_arg(args, int);
+   c = *++fmt;
+   } else {
+   while (isdigit(c)) {
+   width = width * 10 + c - '0';
+   c = *++fmt;
+   }
+   }
+   if (c == '.') {
+   c = *++fmt;
+   if (c == '*') {
+   prec = va_arg(args, int);
+   c = *++fmt;
+   } else {
+   while (isdigit(c)) {
+   prec = prec * 10 + c - '0';
+   c = *++fmt;
+   }
+   }
+   }
+   str = 0;
+   base = 0;
+   neg = 0;
+   ++fmt;
+   switch (c) {
+   case 'd':
+   i = va_arg(args, int);
+   if (i < 0) {
+   neg = 1;
+   val = -i;
+   } else
+   val = i;
+   base = 10;
+   break;
+   case 'o':
+   val = va_arg(args, unsigned int);
+   base = 8;
+   break;
+   case 'x':
+   val = va_arg(args, unsigned int);
+   base = 16;
+   break;
+   case 'p':
+   val = (unsigned long) va_arg(args, void *);
+   base = 16;
+   neg = 2;
+   break;
+   case 's':
+   str = va_arg(args, char *);
+   break;
+   case 'c':
+   num[0] = va_arg(args, int);
+   num[1] = 0;
+   str = num;
+   break;
+   case 'm':
+   str = strerror(errno);
+   break;
+   case 'I':
+   str = ip_ntoa(va_arg(args, u_int32_t));
+   break;
+   case 'r':
+   f = va_arg(args, char *);
+   #ifndef __powerpc__
+   n = vfmtmsg(buf, buflen + 1, f, va_arg(args, va_list));
+   #else
+
+   n = vfmtmsg(buf, buflen + 1, f, va_arg(args, void *));
+   #endif
+   buf += n;
+   buflen -= n;
+   continue;
+   case 't':
+   break;
+   case 'v':         
+   case 'q':     
+   quoted = c == 'q';
+   p = va_arg(args, unsigned char *);
+   if (fillch == '0' && prec > 0) {
+   n = prec;
+   } else {
+   n = strlen((char *)p);
+   if (prec > 0 && prec < n)
+   n = prec;
+   }
+   while (n > 0 && buflen > 0) {
+   c = *p++;
+   --n;
+   if (!quoted && c >= 0x80) {
+   OUTCHAR('M');
+   OUTCHAR('-');
+   c -= 0x80;
+   }
+   if (quoted && (c == '"' || c == '\\'))
+   OUTCHAR('\\');
+   if (c < 0x20 || (0x7f <= c && c < 0xa0)) {
+   if (quoted) {
+   OUTCHAR('\\');
+   switch (c) {
+   case '\t':   OUTCHAR('t');   break;
+   case '\n':   OUTCHAR('n');   break;
+   case '\b':   OUTCHAR('b');   break;
+   case '\f':   OUTCHAR('f');   break;
+   default:
+   OUTCHAR('x');
+   OUTCHAR(hexchars[c >> 4]);
+   OUTCHAR(hexchars[c & 0xf]);
+   }
+   } else {
+   if (c == '\t')
+   OUTCHAR(c);
+   else {
+   OUTCHAR('^');
+   OUTCHAR(c ^ 0x40);
+   }
+   }
+   } else
+   OUTCHAR(c);
+   }
+   continue;
+   default:
+   *buf++ = '%';
+   if (c != '%')
+   --fmt;       
+   --buflen;
+   continue;
+   }
+   if (base != 0) {
+   str = num + sizeof(num);
+   *--str = 0;
+   while (str > num + neg) {
+   *--str = hexchars[val % base];
+   val = val / base;
+   if (--prec <= 0 && val == 0)
+   break;
+   }
+   switch (neg) {
+   case 1:
+   *--str = '-';
+   break;
+   case 2:
+   *--str = 'x';
+   *--str = '0';
+   break;
+   }
+   len = num + sizeof(num) - 1 - str;
+   } else {
+   len = strlen(str);
+   if (prec > 0 && len > prec)
+   len = prec;
+   }
+   if (width > 0) {
+   if (width > buflen)
+   width = buflen;
+   if ((n = width - len) > 0) {
+   buflen -= n;
+   for (; n > 0; --n)
+   *buf++ = fillch;
+   }
+   }
+   if (len > buflen)
+   len = buflen;
+   memcpy(buf, str, len);
+   buf += len;
+   buflen -= len;
+   }
+   *buf = 0;
+   return buf - buf0;
+ */
+	return 0;
+}
+
+
+/*
+ * script_setenv - set an environment variable value to be used
+ * for scripts that we run (e.g. ip-up, auth-up, etc.)
+ */
+#define script_setenv(var, value)
+/*
+   void
+   script_setenv(var, value)
+   char *var, *value;
+   {
+   int vl = strlen(var);
+   int i;
+   char *p, *newstring;
+
+   newstring = (char *) malloc(vl + strlen(value) + 2);
+   if (newstring == 0)
+   return;
+   strcpy(newstring, var);
+   newstring[vl] = '=';
+   strcpy(newstring+vl+1, value);
+
+   if (script_env != 0) {
+   for (i = 0; (p = script_env[i]) != 0; ++i) {
+   if (strncmp(p, var, vl) == 0 && p[vl] == '=') {
+   free(p);
+   script_env[i] = newstring;
+   return;
+   }
+   }
+   } else {
+   i = 0;
+   script_env = (char **) malloc(16 * sizeof(char *));
+   if (script_env == 0)
+   return;
+   s_env_nalloc = 16;
+   }
+
+   if (i + 1 >= s_env_nalloc) {
+   int new_n = i + 17;
+   char **newenv = (char **) realloc((void *)script_env,
+   new_n * sizeof(char *));
+   if (newenv == 0)
+   return;
+   script_env = newenv;
+   s_env_nalloc = new_n;
+   }
+
+   script_env[i] = newstring;
+   script_env[i+1] = 0;
+   }
+
+		    *//*
+		      * script_unsetenv - remove a variable from the environment
+		      * for scripts.
+		    */
+#define script_unsetenv(var)
+/*
+   void
+   script_unsetenv(var)
+   char *var;
+   {
+   int vl = strlen(var);
+   int i;
+   char *p;
+
+   if (script_env == 0)
+   return;
+   for (i = 0; (p = script_env[i]) != 0; ++i) {
+   if (strncmp(p, var, vl) == 0 && p[vl] == '=') {
+   free(p);
+   while ((script_env[i] = script_env[i+1]) != 0)
+   ++i;
+   break;
+   }
+   }
+   }
+ */