Diff: src/netif/ppp/ppp.c

Revision:

0:8e01dca41002

diff -r 000000000000 -r 8e01dca41002 src/netif/ppp/ppp.c
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/netif/ppp/ppp.c	Thu May 24 15:53:48 2012 +0000
@@ -0,0 +1,2044 @@
+/*****************************************************************************
+* ppp.c - Network Point to Point Protocol program file.
+*
+* Copyright (c) 2003 by Marc Boucher, Services Informatiques (MBSI) inc.
+* portions Copyright (c) 1997 by Global Election Systems Inc.
+*
+* The authors hereby grant permission to use, copy, modify, distribute,
+* and license this software and its documentation for any purpose, provided
+* that existing copyright notices are retained in all copies and that this
+* notice and the following disclaimer are included verbatim in any 
+* distributions. No written agreement, license, or royalty fee is required
+* for any of the authorized uses.
+*
+* THIS SOFTWARE IS PROVIDED BY THE 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 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.
+*
+******************************************************************************
+* REVISION HISTORY
+*
+* 03-01-01 Marc Boucher <marc@mbsi.ca>
+*   Ported to lwIP.
+* 97-11-05 Guy Lancaster <lancasterg@acm.org>, Global Election Systems Inc.
+*   Original.
+*****************************************************************************/
+
+/*
+ * ppp_defs.h - PPP definitions.
+ *
+ * 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.
+ */
+
+/*
+ * if_ppp.h - Point-to-Point Protocol definitions.
+ *
+ * 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 MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
+ */
+
+#define __LWIP_ORIG 0
+
+#include "lwip/opt.h"
+
+#if PPP_SUPPORT /* don't build if not configured for use in lwipopts.h */
+
+#include "lwip/ip.h" /* for ip_input() */
+
+#include "ppp.h"
+#include "pppdebug.h"
+
+#include "randm.h"
+#include "fsm.h"
+#if PAP_SUPPORT
+#include "pap.h"
+#endif /* PAP_SUPPORT */
+#if CHAP_SUPPORT
+#include "chap.h"
+#endif /* CHAP_SUPPORT */
+#include "ipcp.h"
+#include "lcp.h"
+#include "magic.h"
+#include "auth.h"
+#if VJ_SUPPORT
+#include "vj.h"
+#endif /* VJ_SUPPORT */
+#if PPPOE_SUPPORT
+#include "netif/ppp_oe.h"
+#endif /* PPPOE_SUPPORT */
+
+#include "lwip/tcpip.h"
+#include "lwip/api.h"
+#include "lwip/snmp.h"
+
+#include <string.h>
+
+/*************************/
+/*** LOCAL DEFINITIONS ***/
+/*************************/
+
+/** PPP_INPROC_MULTITHREADED==1 call pppInput using tcpip_callback().
+ * Set this to 0 if pppInProc is called inside tcpip_thread or with NO_SYS==1.
+ * Default is 1 for NO_SYS==0 (multithreaded) and 0 for NO_SYS==1 (single-threaded).
+ */
+#ifndef PPP_INPROC_MULTITHREADED
+#define PPP_INPROC_MULTITHREADED (NO_SYS==0)
+#endif
+
+/** PPP_INPROC_OWNTHREAD==1: start a dedicated RX thread per PPP session.
+ * Default is 0: call pppos_input() for received raw characters, charcater
+ * reception is up to the port */
+#ifndef PPP_INPROC_OWNTHREAD
+#define PPP_INPROC_OWNTHREAD      PPP_INPROC_MULTITHREADED
+#endif
+
+#if PPP_INPROC_OWNTHREAD && !PPP_INPROC_MULTITHREADED
+  #error "PPP_INPROC_OWNTHREAD needs PPP_INPROC_MULTITHREADED==1"
+#endif
+
+/*
+ * The basic PPP frame.
+ */
+#define PPP_ADDRESS(p)  (((u_char *)(p))[0])
+#define PPP_CONTROL(p)  (((u_char *)(p))[1])
+#define PPP_PROTOCOL(p) ((((u_char *)(p))[2] << 8) + ((u_char *)(p))[3])
+
+/* PPP packet parser states.  Current state indicates operation yet to be
+ * completed. */
+typedef enum {
+  PDIDLE = 0,  /* Idle state - waiting. */
+  PDSTART,     /* Process start flag. */
+  PDADDRESS,   /* Process address field. */
+  PDCONTROL,   /* Process control field. */
+  PDPROTOCOL1, /* Process protocol field 1. */
+  PDPROTOCOL2, /* Process protocol field 2. */
+  PDDATA       /* Process data byte. */
+} PPPDevStates;
+
+#define ESCAPE_P(accm, c) ((accm)[(c) >> 3] & pppACCMMask[c & 0x07])
+
+/************************/
+/*** LOCAL DATA TYPES ***/
+/************************/
+
+/** RX buffer size: this may be configured smaller! */
+#ifndef PPPOS_RX_BUFSIZE
+#define PPPOS_RX_BUFSIZE    (PPP_MRU + PPP_HDRLEN)
+#endif
+
+typedef struct PPPControlRx_s {
+  /** unit number / ppp descriptor */
+  int pd;
+  /** the rx file descriptor */
+  sio_fd_t fd;
+  /** receive buffer - encoded data is stored here */
+  u_char rxbuf[PPPOS_RX_BUFSIZE];
+
+  /* The input packet. */
+  struct pbuf *inHead, *inTail;
+
+#if PPPOS_SUPPORT
+  u16_t inProtocol;             /* The input protocol code. */
+  u16_t inFCS;                  /* Input Frame Check Sequence value. */
+#endif /* PPPOS_SUPPORT */
+  PPPDevStates inState;         /* The input process state. */
+  char inEscaped;               /* Escape next character. */
+  ext_accm inACCM;              /* Async-Ctl-Char-Map for input. */
+} PPPControlRx;
+
+/*
+ * PPP interface control block.
+ */
+typedef struct PPPControl_s {
+  PPPControlRx rx;
+  char openFlag;                /* True when in use. */
+#if PPPOE_SUPPORT
+  struct netif *ethif;
+  struct pppoe_softc *pppoe_sc;
+#endif /* PPPOE_SUPPORT */
+  int  if_up;                   /* True when the interface is up. */
+  int  errCode;                 /* Code indicating why interface is down. */
+#if PPPOS_SUPPORT
+  sio_fd_t fd;                  /* File device ID of port. */
+#endif /* PPPOS_SUPPORT */
+  u16_t mtu;                    /* Peer's mru */
+  int  pcomp;                   /* Does peer accept protocol compression? */
+  int  accomp;                  /* Does peer accept addr/ctl compression? */
+  u_long lastXMit;              /* Time of last transmission. */
+  ext_accm outACCM;             /* Async-Ctl-Char-Map for output. */
+#if PPPOS_SUPPORT && VJ_SUPPORT
+  int  vjEnabled;               /* Flag indicating VJ compression enabled. */
+  struct vjcompress vjComp;     /* Van Jacobson compression header. */
+#endif /* PPPOS_SUPPORT && VJ_SUPPORT */
+
+  struct netif netif;
+
+  struct ppp_addrs addrs;
+
+  void (*linkStatusCB)(void *ctx, int errCode, void *arg);
+  void *linkStatusCtx;
+
+} PPPControl;
+
+
+/*
+ * Ioctl definitions.
+ */
+
+struct npioctl {
+  int         protocol; /* PPP procotol, e.g. PPP_IP */
+  enum NPmode mode;
+};
+
+
+
+/***********************************/
+/*** LOCAL FUNCTION DECLARATIONS ***/
+/***********************************/
+#if PPPOS_SUPPORT
+#if PPP_INPROC_OWNTHREAD
+static void pppInputThread(void *arg);
+#endif /* PPP_INPROC_OWNTHREAD */
+static void pppDrop(PPPControlRx *pcrx);
+static void pppInProc(PPPControlRx *pcrx, u_char *s, int l);
+#endif /* PPPOS_SUPPORT */
+
+
+/******************************/
+/*** PUBLIC DATA STRUCTURES ***/
+/******************************/
+u_long subnetMask;
+
+static PPPControl pppControl[NUM_PPP] __attribute((section("AHBSRAM1"))); //Add DG; /* The PPP interface control blocks. */
+
+#if !__LWIP_ORIG
+    sys_mbox_t pppMbox; //Used to signal PPP thread that a PPP session begins
+#endif
+
+/*
+ * PPP Data Link Layer "protocol" table.
+ * One entry per supported protocol.
+ * The last entry must be NULL.
+ */
+struct protent *ppp_protocols[] = {
+  &lcp_protent,
+#if PAP_SUPPORT
+  &pap_protent,
+#endif /* PAP_SUPPORT */
+#if CHAP_SUPPORT
+  &chap_protent,
+#endif /* CHAP_SUPPORT */
+#if CBCP_SUPPORT
+  &cbcp_protent,
+#endif /* CBCP_SUPPORT */
+  &ipcp_protent,
+#if CCP_SUPPORT
+  &ccp_protent,
+#endif /* CCP_SUPPORT */
+  NULL
+};
+
+
+/*
+ * Buffers for outgoing packets.  This must be accessed only from the appropriate
+ * PPP task so that it doesn't need to be protected to avoid collisions.
+ */
+u_char outpacket_buf[NUM_PPP][PPP_MRU+PPP_HDRLEN] __attribute((section("AHBSRAM1")));
+
+
+/*****************************/
+/*** LOCAL DATA STRUCTURES ***/
+/*****************************/
+
+#if PPPOS_SUPPORT
+/*
+ * FCS lookup table as calculated by genfcstab.
+ * @todo: smaller, slower implementation for lower memory footprint?
+ */
+static const 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
+};
+
+/* PPP's Asynchronous-Control-Character-Map.  The mask array is used
+ * to select the specific bit for a character. */
+static u_char pppACCMMask[] = {
+  0x01,
+  0x02,
+  0x04,
+  0x08,
+  0x10,
+  0x20,
+  0x40,
+  0x80
+};
+
+/** Wake up the task blocked in reading from serial line (if any) */
+static void
+pppRecvWakeup(int pd)
+{
+  PPPDEBUG(LOG_DEBUG, ("pppRecvWakeup: unit %d\n", pd));
+  if (pppControl[pd].openFlag != 0) {
+    sio_read_abort(pppControl[pd].fd);
+  }
+}
+#endif /* PPPOS_SUPPORT */
+
+void
+pppLinkTerminated(int pd)
+{
+  PPPDEBUG(LOG_DEBUG, ("pppLinkTerminated: unit %d\n", pd));
+
+#if PPPOE_SUPPORT
+  if (pppControl[pd].ethif) {
+    pppoe_disconnect(pppControl[pd].pppoe_sc);
+  } else
+#endif /* PPPOE_SUPPORT */
+  {
+#if PPPOS_SUPPORT
+    PPPControl* pc;
+    pppRecvWakeup(pd);
+    pc = &pppControl[pd];
+
+    PPPDEBUG(LOG_DEBUG, ("pppLinkTerminated: unit %d: linkStatusCB=%p errCode=%d\n", pd, pc->linkStatusCB, pc->errCode));
+    if (pc->linkStatusCB) {
+      pc->linkStatusCB(pc->linkStatusCtx, pc->errCode ? pc->errCode : PPPERR_PROTOCOL, NULL);
+    }
+
+    pc->openFlag = 0;/**/
+#endif /* PPPOS_SUPPORT */
+  }
+  PPPDEBUG(LOG_DEBUG, ("pppLinkTerminated: finished.\n"));
+}
+
+void
+pppLinkDown(int pd)
+{
+  PPPDEBUG(LOG_DEBUG, ("pppLinkDown: unit %d\n", pd));
+
+#if PPPOE_SUPPORT
+  if (pppControl[pd].ethif) {
+    pppoe_disconnect(pppControl[pd].pppoe_sc);
+  } else
+#endif /* PPPOE_SUPPORT */
+  {
+#if PPPOS_SUPPORT
+    pppRecvWakeup(pd);
+#endif /* PPPOS_SUPPORT */
+  }
+}
+
+/** Initiate LCP open request */
+static void
+pppStart(int pd)
+{
+  PPPDEBUG(LOG_DEBUG, ("pppStart: unit %d\n", pd));
+  lcp_lowerup(pd);
+  lcp_open(pd); /* Start protocol */
+  PPPDEBUG(LOG_DEBUG, ("pppStart: finished\n"));
+}
+
+/** LCP close request */
+static void
+pppStop(int pd)
+{
+  PPPDEBUG(LOG_DEBUG, ("pppStop: unit %d\n", pd));
+  lcp_close(pd, "User request");
+}
+
+/** Called when carrier/link is lost */
+static void
+pppHup(int pd)
+{
+  PPPDEBUG(LOG_DEBUG, ("pppHupCB: unit %d\n", pd));
+  lcp_lowerdown(pd);
+  link_terminated(pd);
+}
+
+/***********************************/
+/*** PUBLIC FUNCTION DEFINITIONS ***/
+/***********************************/
+/* Initialize the PPP subsystem. */
+
+struct ppp_settings ppp_settings;
+
+void
+pppInit(void)
+{
+  struct protent *protp;
+  int i, j;
+
+  memset(&ppp_settings, 0, sizeof(ppp_settings));
+  ppp_settings.usepeerdns = 1;
+  pppSetAuth(PPPAUTHTYPE_NONE, NULL, NULL);
+
+  magicInit();
+
+  subnetMask = PP_HTONL(0xffffff00UL);
+
+  for (i = 0; i < NUM_PPP; i++) {
+    /* Initialize each protocol to the standard option set. */
+    for (j = 0; (protp = ppp_protocols[j]) != NULL; ++j) {
+      (*protp->init)(i);
+    }
+  }
+
+  #if !__LWIP_ORIG
+  sys_mbox_new(&pppMbox, 1);
+  sys_thread_new(PPP_THREAD_NAME, pppInputThread, (void*)NULL, PPP_THREAD_STACKSIZE, PPP_THREAD_PRIO); //Create PPP thread here
+  #endif
+}
+
+void
+pppSetAuth(enum pppAuthType authType, const char *user, const char *passwd)
+{
+  switch(authType) {
+    case PPPAUTHTYPE_NONE:
+    default:
+#ifdef LWIP_PPP_STRICT_PAP_REJECT
+      ppp_settings.refuse_pap = 1;
+#else  /* LWIP_PPP_STRICT_PAP_REJECT */
+      /* some providers request pap and accept an empty login/pw */
+      ppp_settings.refuse_pap = 0;
+#endif /* LWIP_PPP_STRICT_PAP_REJECT */
+      ppp_settings.refuse_chap = 1;
+      break;
+
+    case PPPAUTHTYPE_ANY:
+      /* Warning: Using PPPAUTHTYPE_ANY might have security consequences.
+       * RFC 1994 says:
+       *
+       * In practice, within or associated with each PPP server, there is a
+       * database which associates "user" names with authentication
+       * information ("secrets").  It is not anticipated that a particular
+       * named user would be authenticated by multiple methods.  This would
+       * make the user vulnerable to attacks which negotiate the least secure
+       * method from among a set (such as PAP rather than CHAP).  If the same
+       * secret was used, PAP would reveal the secret to be used later with
+       * CHAP.
+       *
+       * Instead, for each user name there should be an indication of exactly
+       * one method used to authenticate that user name.  If a user needs to
+       * make use of different authentication methods under different
+       * circumstances, then distinct user names SHOULD be employed, each of
+       * which identifies exactly one authentication method.
+       *
+       */
+      ppp_settings.refuse_pap = 0;
+      ppp_settings.refuse_chap = 0;
+      break;
+
+    case PPPAUTHTYPE_PAP:
+      ppp_settings.refuse_pap = 0;
+      ppp_settings.refuse_chap = 1;
+      break;
+
+    case PPPAUTHTYPE_CHAP:
+      ppp_settings.refuse_pap = 1;
+      ppp_settings.refuse_chap = 0;
+      break;
+  }
+
+  if(user) {
+    strncpy(ppp_settings.user, user, sizeof(ppp_settings.user)-1);
+    ppp_settings.user[sizeof(ppp_settings.user)-1] = '\0';
+  } else {
+    ppp_settings.user[0] = '\0';
+  }
+
+  if(passwd) {
+    strncpy(ppp_settings.passwd, passwd, sizeof(ppp_settings.passwd)-1);
+    ppp_settings.passwd[sizeof(ppp_settings.passwd)-1] = '\0';
+  } else {
+    ppp_settings.passwd[0] = '\0';
+  }
+}
+
+#if PPPOS_SUPPORT
+/** Open a new PPP connection using the given I/O device.
+ * This initializes the PPP control block but does not
+ * attempt to negotiate the LCP session.  If this port
+ * connects to a modem, the modem connection must be
+ * established before calling this.
+ * Return a new PPP connection descriptor on success or
+ * an error code (negative) on failure.
+ *
+ * pppOpen() is directly defined to this function.
+ */
+int
+pppOverSerialOpen(sio_fd_t fd, void (*linkStatusCB)(void *ctx, int errCode, void *arg), void *linkStatusCtx)
+{
+  PPPControl *pc;
+  int pd;
+
+  if (linkStatusCB == NULL) {
+    /* PPP is single-threaded: without a callback,
+     * there is no way to know when the link is up. */
+    return PPPERR_PARAM;
+  }
+
+  /* Find a free PPP session descriptor. */
+  for (pd = 0; pd < NUM_PPP && pppControl[pd].openFlag != 0; pd++);
+
+  if (pd >= NUM_PPP) {
+    pd = PPPERR_OPEN;
+  } else {
+    pc = &pppControl[pd];
+    /* @todo: is this correct or do I overwrite something? */
+    memset(pc, 0, sizeof(PPPControl));
+    pc->rx.pd = pd;
+    pc->rx.fd = fd;
+
+    pc->openFlag = 1;
+    pc->fd = fd;
+
+#if VJ_SUPPORT
+    vj_compress_init(&pc->vjComp);
+#endif /* VJ_SUPPORT */
+
+    /* 
+     * Default the in and out accm so that escape and flag characters
+     * are always escaped. 
+     */
+    pc->rx.inACCM[15] = 0x60; /* no need to protect since RX is not running */
+    pc->outACCM[15] = 0x60;
+
+    pc->linkStatusCB = linkStatusCB;
+    pc->linkStatusCtx = linkStatusCtx;
+
+    /*
+     * Start the connection and handle incoming events (packet or timeout).
+     */
+    PPPDEBUG(LOG_INFO, ("pppOverSerialOpen: unit %d: Connecting\n", pd));
+    pppStart(pd);
+#if PPP_INPROC_OWNTHREAD
+#if __LWIP_ORIG
+    sys_thread_new(PPP_THREAD_NAME, pppInputThread, (void*)&pc->rx, PPP_THREAD_STACKSIZE, PPP_THREAD_PRIO);
+#else
+    sys_mbox_post(&pppMbox, (void*)&pc->rx);
+#endif
+#endif
+  }
+
+  return pd;
+}
+#endif /* PPPOS_SUPPORT */
+
+#if PPPOE_SUPPORT
+static void pppOverEthernetLinkStatusCB(int pd, int up);
+
+void
+pppOverEthernetClose(int pd)
+{
+  PPPControl* pc = &pppControl[pd];
+
+  /* *TJL* There's no lcp_deinit */
+  lcp_close(pd, NULL);
+
+  pppoe_destroy(&pc->netif);
+}
+
+int pppOverEthernetOpen(struct netif *ethif, const char *service_name, const char *concentrator_name, void (*linkStatusCB)(void *ctx, int errCode, void *arg), void *linkStatusCtx)
+{
+  PPPControl *pc;
+  int pd;
+
+  LWIP_UNUSED_ARG(service_name);
+  LWIP_UNUSED_ARG(concentrator_name);
+
+  if (linkStatusCB == NULL) {
+    /* PPP is single-threaded: without a callback,
+     * there is no way to know when the link is up. */
+    return PPPERR_PARAM;
+  }
+
+  /* Find a free PPP session descriptor. Critical region? */
+  for (pd = 0; pd < NUM_PPP && pppControl[pd].openFlag != 0; pd++);
+  if (pd >= NUM_PPP) {
+    pd = PPPERR_OPEN;
+  } else {
+    pc = &pppControl[pd];
+    memset(pc, 0, sizeof(PPPControl));
+    pc->openFlag = 1;
+    pc->ethif = ethif;
+
+    pc->linkStatusCB  = linkStatusCB;
+    pc->linkStatusCtx = linkStatusCtx;
+
+    lcp_wantoptions[pd].mru = PPPOE_MAXMTU;
+    lcp_wantoptions[pd].neg_asyncmap = 0;
+    lcp_wantoptions[pd].neg_pcompression = 0;
+    lcp_wantoptions[pd].neg_accompression = 0;
+
+    lcp_allowoptions[pd].mru = PPPOE_MAXMTU;
+    lcp_allowoptions[pd].neg_asyncmap = 0;
+    lcp_allowoptions[pd].neg_pcompression = 0;
+    lcp_allowoptions[pd].neg_accompression = 0;
+
+    if(pppoe_create(ethif, pd, pppOverEthernetLinkStatusCB, &pc->pppoe_sc) != ERR_OK) {
+      pc->openFlag = 0;
+      return PPPERR_OPEN;
+    }
+
+    pppoe_connect(pc->pppoe_sc);
+  }
+
+  return pd;
+}
+#endif /* PPPOE_SUPPORT */
+
+
+/* Close a PPP connection and release the descriptor. 
+ * Any outstanding packets in the queues are dropped.
+ * Return 0 on success, an error code on failure. */
+int
+pppClose(int pd)
+{
+  PPPControl *pc = &pppControl[pd];
+  int st = 0;
+
+  PPPDEBUG(LOG_DEBUG, ("pppClose() called\n"));
+
+  /* Disconnect */
+#if PPPOE_SUPPORT
+  if(pc->ethif) {
+    PPPDEBUG(LOG_DEBUG, ("pppClose: unit %d kill_link -> pppStop\n", pd));
+    pc->errCode = PPPERR_USER;
+    /* This will leave us at PHASE_DEAD. */
+    pppStop(pd);
+  } else
+#endif /* PPPOE_SUPPORT */
+  {
+#if PPPOS_SUPPORT
+    PPPDEBUG(LOG_DEBUG, ("pppClose: unit %d kill_link -> pppStop\n", pd));
+    pc->errCode = PPPERR_USER;
+    /* This will leave us at PHASE_DEAD. */
+    pppStop(pd);
+    pppRecvWakeup(pd);
+#endif /* PPPOS_SUPPORT */
+  }
+
+  return st;
+}
+
+/* This function is called when carrier is lost on the PPP channel. */
+void
+pppSigHUP(int pd)
+{
+  PPPDEBUG(LOG_DEBUG, ("pppSigHUP: unit %d sig_hup -> pppHupCB\n", pd));
+  pppHup(pd);
+}
+
+#if PPPOS_SUPPORT
+static void
+nPut(PPPControl *pc, struct pbuf *nb)
+{
+  struct pbuf *b;
+  int c;
+
+  for(b = nb; b != NULL; b = b->next) {
+    if((c = sio_write(pc->fd, b->payload, b->len)) != b->len) {
+      PPPDEBUG(LOG_WARNING,
+               ("PPP nPut: incomplete sio_write(fd:%"SZT_F", len:%d, c: 0x%"X8_F") c = %d\n", (size_t)pc->fd, b->len, c, c));
+      LINK_STATS_INC(link.err);
+      pc->lastXMit = 0; /* prepend PPP_FLAG to next packet */
+      snmp_inc_ifoutdiscards(&pc->netif);
+      pbuf_free(nb);
+      return;
+    }
+  }
+
+  snmp_add_ifoutoctets(&pc->netif, nb->tot_len);
+  snmp_inc_ifoutucastpkts(&pc->netif);
+  pbuf_free(nb);
+  LINK_STATS_INC(link.xmit);
+}
+
+/* 
+ * pppAppend - append given character to end of given pbuf.  If outACCM
+ * is not NULL and the character needs to be escaped, do so.
+ * If pbuf is full, append another.
+ * Return the current pbuf.
+ */
+static struct pbuf *
+pppAppend(u_char c, struct pbuf *nb, ext_accm *outACCM)
+{
+  struct pbuf *tb = nb;
+  
+  /* Make sure there is room for the character and an escape code.
+   * Sure we don't quite fill the buffer if the character doesn't
+   * get escaped but is one character worth complicating this? */
+  /* Note: We assume no packet header. */
+  if (nb && (PBUF_POOL_BUFSIZE - nb->len) < 2) {
+    tb = pbuf_alloc(PBUF_RAW, 0, PBUF_POOL);
+    if (tb) {
+      nb->next = tb;
+    } else {
+      LINK_STATS_INC(link.memerr);
+    }
+    nb = tb;
+  }
+
+  if (nb) {
+    if (outACCM && ESCAPE_P(*outACCM, c)) {
+      *((u_char*)nb->payload + nb->len++) = PPP_ESCAPE;
+      *((u_char*)nb->payload + nb->len++) = c ^ PPP_TRANS;
+    } else {
+      *((u_char*)nb->payload + nb->len++) = c;
+    }
+  }
+
+  return tb;
+}
+#endif /* PPPOS_SUPPORT */
+
+#if PPPOE_SUPPORT
+static err_t
+pppifOutputOverEthernet(int pd, struct pbuf *p)
+{
+  PPPControl *pc = &pppControl[pd];
+  struct pbuf *pb;
+  u_short protocol = PPP_IP;
+  int i=0;
+  u16_t tot_len;
+
+  /* @todo: try to use pbuf_header() here! */
+  pb = pbuf_alloc(PBUF_LINK, PPPOE_HDRLEN + sizeof(protocol), PBUF_RAM);
+  if(!pb) {
+    LINK_STATS_INC(link.memerr);
+    LINK_STATS_INC(link.proterr);
+    snmp_inc_ifoutdiscards(&pc->netif);
+    return ERR_MEM;
+  }
+
+  pbuf_header(pb, -(s16_t)PPPOE_HDRLEN);
+
+  pc->lastXMit = sys_jiffies();
+
+  if (!pc->pcomp || protocol > 0xFF) {
+    *((u_char*)pb->payload + i++) = (protocol >> 8) & 0xFF;
+  }
+  *((u_char*)pb->payload + i) = protocol & 0xFF;
+
+  pbuf_chain(pb, p);
+  tot_len = pb->tot_len;
+
+  if(pppoe_xmit(pc->pppoe_sc, pb) != ERR_OK) {
+    LINK_STATS_INC(link.err);
+    snmp_inc_ifoutdiscards(&pc->netif);
+    return PPPERR_DEVICE;
+  }
+
+  snmp_add_ifoutoctets(&pc->netif, tot_len);
+  snmp_inc_ifoutucastpkts(&pc->netif);
+  LINK_STATS_INC(link.xmit);
+  return ERR_OK;
+}
+#endif /* PPPOE_SUPPORT */
+
+/* Send a packet on the given connection. */
+static err_t
+pppifOutput(struct netif *netif, struct pbuf *pb, ip_addr_t *ipaddr)
+{
+  int pd = (int)(size_t)netif->state;
+  PPPControl *pc = &pppControl[pd];
+#if PPPOS_SUPPORT
+  u_short protocol = PPP_IP;
+  u_int fcsOut = PPP_INITFCS;
+  struct pbuf *headMB = NULL, *tailMB = NULL, *p;
+  u_char c;
+#endif /* PPPOS_SUPPORT */
+
+  LWIP_UNUSED_ARG(ipaddr);
+
+  /* Validate parameters. */
+  /* We let any protocol value go through - it can't hurt us
+   * and the peer will just drop it if it's not accepting it. */
+  if (pd < 0 || pd >= NUM_PPP || !pc->openFlag || !pb) {
+    PPPDEBUG(LOG_WARNING, ("pppifOutput[%d]: bad parms prot=%d pb=%p\n",
+              pd, PPP_IP, pb));
+    LINK_STATS_INC(link.opterr);
+    LINK_STATS_INC(link.drop);
+    snmp_inc_ifoutdiscards(netif);
+    return ERR_ARG;
+  }
+
+  /* Check that the link is up. */
+  if (lcp_phase[pd] == PHASE_DEAD) {
+    PPPDEBUG(LOG_ERR, ("pppifOutput[%d]: link not up\n", pd));
+    LINK_STATS_INC(link.rterr);
+    LINK_STATS_INC(link.drop);
+    snmp_inc_ifoutdiscards(netif);
+    return ERR_RTE;
+  }
+
+#if PPPOE_SUPPORT
+  if(pc->ethif) {
+    return pppifOutputOverEthernet(pd, pb);
+  }
+#endif /* PPPOE_SUPPORT */
+
+#if PPPOS_SUPPORT
+  /* Grab an output buffer. */
+  headMB = pbuf_alloc(PBUF_RAW, 0, PBUF_POOL);
+  if (headMB == NULL) {
+    PPPDEBUG(LOG_WARNING, ("pppifOutput[%d]: first alloc fail\n", pd));
+    LINK_STATS_INC(link.memerr);
+    LINK_STATS_INC(link.drop);
+    snmp_inc_ifoutdiscards(netif);
+    return ERR_MEM;
+  }
+
+#if VJ_SUPPORT
+  /* 
+   * Attempt Van Jacobson header compression if VJ is configured and
+   * this is an IP packet. 
+   */
+  if (protocol == PPP_IP && pc->vjEnabled) {
+    switch (vj_compress_tcp(&pc->vjComp, pb)) {
+      case TYPE_IP:
+        /* No change...
+           protocol = PPP_IP_PROTOCOL; */
+        break;
+      case TYPE_COMPRESSED_TCP:
+        protocol = PPP_VJC_COMP;
+        break;
+      case TYPE_UNCOMPRESSED_TCP:
+        protocol = PPP_VJC_UNCOMP;
+        break;
+      default:
+        PPPDEBUG(LOG_WARNING, ("pppifOutput[%d]: bad IP packet\n", pd));
+        LINK_STATS_INC(link.proterr);
+        LINK_STATS_INC(link.drop);
+        snmp_inc_ifoutdiscards(netif);
+        pbuf_free(headMB);
+        return ERR_VAL;
+    }
+  }
+#endif /* VJ_SUPPORT */
+
+  tailMB = headMB;
+
+  /* Build the PPP header. */
+  if ((sys_jiffies() - pc->lastXMit) >= PPP_MAXIDLEFLAG) {
+    tailMB = pppAppend(PPP_FLAG, tailMB, NULL);
+  }
+
+  pc->lastXMit = sys_jiffies();
+  if (!pc->accomp) {
+    fcsOut = PPP_FCS(fcsOut, PPP_ALLSTATIONS);
+    tailMB = pppAppend(PPP_ALLSTATIONS, tailMB, &pc->outACCM);
+    fcsOut = PPP_FCS(fcsOut, PPP_UI);
+    tailMB = pppAppend(PPP_UI, tailMB, &pc->outACCM);
+  }
+  if (!pc->pcomp || protocol > 0xFF) {
+    c = (protocol >> 8) & 0xFF;
+    fcsOut = PPP_FCS(fcsOut, c);
+    tailMB = pppAppend(c, tailMB, &pc->outACCM);
+  }
+  c = protocol & 0xFF;
+  fcsOut = PPP_FCS(fcsOut, c);
+  tailMB = pppAppend(c, tailMB, &pc->outACCM);
+
+  /* Load packet. */
+  for(p = pb; p; p = p->next) {
+    int n;
+    u_char *sPtr;
+
+    sPtr = (u_char*)p->payload;
+    n = p->len;
+    while (n-- > 0) {
+      c = *sPtr++;
+
+      /* Update FCS before checking for special characters. */
+      fcsOut = PPP_FCS(fcsOut, c);
+      
+      /* Copy to output buffer escaping special characters. */
+      tailMB = pppAppend(c, tailMB, &pc->outACCM);
+    }
+  }
+
+  /* Add FCS and trailing flag. */
+  c = ~fcsOut & 0xFF;
+  tailMB = pppAppend(c, tailMB, &pc->outACCM);
+  c = (~fcsOut >> 8) & 0xFF;
+  tailMB = pppAppend(c, tailMB, &pc->outACCM);
+  tailMB = pppAppend(PPP_FLAG, tailMB, NULL);
+
+  /* If we failed to complete the packet, throw it away. */
+  if (!tailMB) {
+    PPPDEBUG(LOG_WARNING,
+             ("pppifOutput[%d]: Alloc err - dropping proto=%d\n", 
+              pd, protocol));
+    pbuf_free(headMB);
+    LINK_STATS_INC(link.memerr);
+    LINK_STATS_INC(link.drop);
+    snmp_inc_ifoutdiscards(netif);
+    return ERR_MEM;
+  }
+
+  /* Send it. */
+  PPPDEBUG(LOG_INFO, ("pppifOutput[%d]: proto=0x%"X16_F"\n", pd, protocol));
+
+  nPut(pc, headMB);
+#endif /* PPPOS_SUPPORT */
+
+  return ERR_OK;
+}
+
+/* Get and set parameters for the given connection.
+ * Return 0 on success, an error code on failure. */
+int
+pppIOCtl(int pd, int cmd, void *arg)
+{
+  PPPControl *pc = &pppControl[pd];
+  int st = 0;
+
+  if (pd < 0 || pd >= NUM_PPP) {
+    st = PPPERR_PARAM;
+  } else {
+    switch(cmd) {
+    case PPPCTLG_UPSTATUS:      /* Get the PPP up status. */
+      if (arg) {
+        *(int *)arg = (int)(pc->if_up);
+      } else {
+        st = PPPERR_PARAM;
+      }
+      break;
+    case PPPCTLS_ERRCODE:       /* Set the PPP error code. */
+      if (arg) {
+        pc->errCode = *(int *)arg;
+      } else {
+        st = PPPERR_PARAM;
+      }
+      break;
+    case PPPCTLG_ERRCODE:       /* Get the PPP error code. */
+      if (arg) {
+        *(int *)arg = (int)(pc->errCode);
+      } else {
+        st = PPPERR_PARAM;
+      }
+      break;
+#if PPPOS_SUPPORT
+    case PPPCTLG_FD:            /* Get the fd associated with the ppp */
+      if (arg) {
+        *(sio_fd_t *)arg = pc->fd;
+      } else {
+        st = PPPERR_PARAM;
+      }
+      break;
+#endif /* PPPOS_SUPPORT */
+    default:
+      st = PPPERR_PARAM;
+      break;
+    }
+  }
+
+  return st;
+}
+
+/*
+ * Return the Maximum Transmission Unit for the given PPP connection.
+ */
+u_short
+pppMTU(int pd)
+{
+  PPPControl *pc = &pppControl[pd];
+  u_short st;
+
+  /* Validate parameters. */
+  if (pd < 0 || pd >= NUM_PPP || !pc->openFlag) {
+    st = 0;
+  } else {
+    st = pc->mtu;
+  }
+
+  return st;
+}
+
+#if PPPOE_SUPPORT
+int
+pppWriteOverEthernet(int pd, const u_char *s, int n)
+{
+  PPPControl *pc = &pppControl[pd];
+  struct pbuf *pb;
+
+  /* skip address & flags */
+  s += 2;
+  n -= 2;
+
+  LWIP_ASSERT("PPPOE_HDRLEN + n <= 0xffff", PPPOE_HDRLEN + n <= 0xffff);
+  pb = pbuf_alloc(PBUF_LINK, (u16_t)(PPPOE_HDRLEN + n), PBUF_RAM);
+  if(!pb) {
+    LINK_STATS_INC(link.memerr);
+    LINK_STATS_INC(link.proterr);
+    snmp_inc_ifoutdiscards(&pc->netif);
+    return PPPERR_ALLOC;
+  }
+
+  pbuf_header(pb, -(s16_t)PPPOE_HDRLEN);
+
+  pc->lastXMit = sys_jiffies();
+
+  MEMCPY(pb->payload, s, n);
+
+  if(pppoe_xmit(pc->pppoe_sc, pb) != ERR_OK) {
+    LINK_STATS_INC(link.err);
+    snmp_inc_ifoutdiscards(&pc->netif);
+    return PPPERR_DEVICE;
+  }
+
+  snmp_add_ifoutoctets(&pc->netif, (u16_t)n);
+  snmp_inc_ifoutucastpkts(&pc->netif);
+  LINK_STATS_INC(link.xmit);
+  return PPPERR_NONE;
+}
+#endif /* PPPOE_SUPPORT */
+
+/*
+ * Write n characters to a ppp link.
+ *  RETURN: >= 0 Number of characters written
+ *           -1 Failed to write to device
+ */
+int
+pppWrite(int pd, const u_char *s, int n)
+{
+  PPPControl *pc = &pppControl[pd];
+#if PPPOS_SUPPORT
+  u_char c;
+  u_int fcsOut;
+  struct pbuf *headMB, *tailMB;
+#endif /* PPPOS_SUPPORT */
+
+#if PPPOE_SUPPORT
+  if(pc->ethif) {
+    return pppWriteOverEthernet(pd, s, n);
+  }
+#endif /* PPPOE_SUPPORT */
+
+#if PPPOS_SUPPORT
+  headMB = pbuf_alloc(PBUF_RAW, 0, PBUF_POOL);
+  if (headMB == NULL) {
+    LINK_STATS_INC(link.memerr);
+    LINK_STATS_INC(link.proterr);
+    snmp_inc_ifoutdiscards(&pc->netif);
+    return PPPERR_ALLOC;
+  }
+
+  tailMB = headMB;
+
+  /* If the link has been idle, we'll send a fresh flag character to
+   * flush any noise. */
+  if ((sys_jiffies() - pc->lastXMit) >= PPP_MAXIDLEFLAG) {
+    tailMB = pppAppend(PPP_FLAG, tailMB, NULL);
+  }
+  pc->lastXMit = sys_jiffies();
+
+  fcsOut = PPP_INITFCS;
+  /* Load output buffer. */
+  while (n-- > 0) {
+    c = *s++;
+
+    /* Update FCS before checking for special characters. */
+    fcsOut = PPP_FCS(fcsOut, c);
+
+    /* Copy to output buffer escaping special characters. */
+    tailMB = pppAppend(c, tailMB, &pc->outACCM);
+  }
+    
+  /* Add FCS and trailing flag. */
+  c = ~fcsOut & 0xFF;
+  tailMB = pppAppend(c, tailMB, &pc->outACCM);
+  c = (~fcsOut >> 8) & 0xFF;
+  tailMB = pppAppend(c, tailMB, &pc->outACCM);
+  tailMB = pppAppend(PPP_FLAG, tailMB, NULL);
+
+  /* If we failed to complete the packet, throw it away.
+   * Otherwise send it. */
+  if (!tailMB) {
+    PPPDEBUG(LOG_WARNING,
+             ("pppWrite[%d]: Alloc err - dropping pbuf len=%d\n", pd, headMB->len));
+           /*"pppWrite[%d]: Alloc err - dropping %d:%.*H", pd, headMB->len, LWIP_MIN(headMB->len * 2, 40), headMB->payload)); */
+    pbuf_free(headMB);
+    LINK_STATS_INC(link.memerr);
+    LINK_STATS_INC(link.proterr);
+    snmp_inc_ifoutdiscards(&pc->netif);
+    return PPPERR_ALLOC;
+  }
+
+  PPPDEBUG(LOG_INFO, ("pppWrite[%d]: len=%d\n", pd, headMB->len));
+                   /* "pppWrite[%d]: %d:%.*H", pd, headMB->len, LWIP_MIN(headMB->len * 2, 40), headMB->payload)); */
+  nPut(pc, headMB);
+#endif /* PPPOS_SUPPORT */
+
+  return PPPERR_NONE;
+}
+
+/*
+ * ppp_send_config - configure the transmit characteristics of
+ * the ppp interface.
+ */
+void
+ppp_send_config( int unit, u16_t mtu, u32_t asyncmap, int pcomp, int accomp)
+{
+  PPPControl *pc = &pppControl[unit];
+  int i;
+  
+  pc->mtu = mtu;
+  pc->pcomp = pcomp;
+  pc->accomp = accomp;
+  
+  /* Load the ACCM bits for the 32 control codes. */
+  for (i = 0; i < 32/8; i++) {
+    pc->outACCM[i] = (u_char)((asyncmap >> (8 * i)) & 0xFF);
+  }
+  PPPDEBUG(LOG_INFO, ("ppp_send_config[%d]: outACCM=%X %X %X %X\n",
+            unit,
+            pc->outACCM[0], pc->outACCM[1], pc->outACCM[2], pc->outACCM[3]));
+}
+
+
+/*
+ * ppp_set_xaccm - set the extended transmit ACCM for the interface.
+ */
+void
+ppp_set_xaccm(int unit, ext_accm *accm)
+{
+  SMEMCPY(pppControl[unit].outACCM, accm, sizeof(ext_accm));
+  PPPDEBUG(LOG_INFO, ("ppp_set_xaccm[%d]: outACCM=%X %X %X %X\n",
+            unit,
+            pppControl[unit].outACCM[0],
+            pppControl[unit].outACCM[1],
+            pppControl[unit].outACCM[2],
+            pppControl[unit].outACCM[3]));
+}
+
+
+/*
+ * ppp_recv_config - configure the receive-side characteristics of
+ * the ppp interface.
+ */
+void
+ppp_recv_config( int unit, int mru, u32_t asyncmap, int pcomp, int accomp)
+{
+  PPPControl *pc = &pppControl[unit];
+  int i;
+  SYS_ARCH_DECL_PROTECT(lev);
+
+  LWIP_UNUSED_ARG(accomp);
+  LWIP_UNUSED_ARG(pcomp);
+  LWIP_UNUSED_ARG(mru);
+
+  /* Load the ACCM bits for the 32 control codes. */
+  SYS_ARCH_PROTECT(lev);
+  for (i = 0; i < 32 / 8; i++) {
+    /* @todo: does this work? ext_accm has been modified from pppd! */
+    pc->rx.inACCM[i] = (u_char)(asyncmap >> (i * 8));
+  }
+  SYS_ARCH_UNPROTECT(lev);
+  PPPDEBUG(LOG_INFO, ("ppp_recv_config[%d]: inACCM=%X %X %X %X\n",
+            unit,
+            pc->rx.inACCM[0], pc->rx.inACCM[1], pc->rx.inACCM[2], pc->rx.inACCM[3]));
+}
+
+#if 0
+/*
+ * ccp_test - ask kernel whether a given compression method
+ * is acceptable for use.  Returns 1 if the method and parameters
+ * are OK, 0 if the method is known but the parameters are not OK
+ * (e.g. code size should be reduced), or -1 if the method is unknown.
+ */
+int
+ccp_test( int unit, int opt_len,  int for_transmit, u_char *opt_ptr)
+{
+  return 0; /* XXX Currently no compression. */
+}
+
+/*
+ * ccp_flags_set - inform kernel about the current state of CCP.
+ */
+void
+ccp_flags_set(int unit, int isopen, int isup)
+{
+  /* XXX */
+}
+
+/*
+ * ccp_fatal_error - returns 1 if decompression was disabled as a
+ * result of an error detected after decompression of a packet,
+ * 0 otherwise.  This is necessary because of patent nonsense.
+ */
+int
+ccp_fatal_error(int unit)
+{
+  /* XXX */
+  return 0;
+}
+#endif
+
+/*
+ * get_idle_time - return how long the link has been idle.
+ */
+int
+get_idle_time(int u, struct ppp_idle *ip)
+{
+  /* XXX */
+  LWIP_UNUSED_ARG(u);
+  LWIP_UNUSED_ARG(ip);
+
+  return 0;
+}
+
+
+/*
+ * Return user specified netmask, modified by any mask we might determine
+ * for address `addr' (in network byte order).
+ * Here we scan through the system's list of interfaces, looking for
+ * any non-point-to-point interfaces which might appear to be on the same
+ * network as `addr'.  If we find any, we OR in their netmask to the
+ * user-specified netmask.
+ */
+u32_t
+GetMask(u32_t addr)
+{
+  u32_t mask, nmask;
+
+  htonl(addr);
+  if (IP_CLASSA(addr)) { /* determine network mask for address class */
+    nmask = IP_CLASSA_NET;
+  } else if (IP_CLASSB(addr)) {
+    nmask = IP_CLASSB_NET;
+  } else { 
+    nmask = IP_CLASSC_NET;
+  }
+
+  /* class D nets are disallowed by bad_ip_adrs */
+  mask = subnetMask | htonl(nmask);
+  
+  /* XXX
+   * Scan through the system's network interfaces.
+   * Get each netmask and OR them into our mask.
+   */
+
+  return mask;
+}
+
+/*
+ * sifvjcomp - config tcp header compression
+ */
+int
+sifvjcomp(int pd, int vjcomp, u8_t cidcomp, u8_t maxcid)
+{
+#if PPPOS_SUPPORT && VJ_SUPPORT
+  PPPControl *pc = &pppControl[pd];
+  
+  pc->vjEnabled = vjcomp;
+  pc->vjComp.compressSlot = cidcomp;
+  pc->vjComp.maxSlotIndex = maxcid;
+  PPPDEBUG(LOG_INFO, ("sifvjcomp: VJ compress enable=%d slot=%d max slot=%d\n",
+            vjcomp, cidcomp, maxcid));
+#else /* PPPOS_SUPPORT && VJ_SUPPORT */
+  LWIP_UNUSED_ARG(pd);
+  LWIP_UNUSED_ARG(vjcomp);
+  LWIP_UNUSED_ARG(cidcomp);
+  LWIP_UNUSED_ARG(maxcid);
+#endif /* PPPOS_SUPPORT && VJ_SUPPORT */
+
+  return 0;
+}
+
+/*
+ * pppifNetifInit - netif init callback
+ */
+static err_t
+pppifNetifInit(struct netif *netif)
+{
+  netif->name[0] = 'p';
+  netif->name[1] = 'p';
+  netif->output = pppifOutput;
+  netif->mtu = pppMTU((int)(size_t)netif->state);
+  netif->flags = NETIF_FLAG_POINTTOPOINT | NETIF_FLAG_LINK_UP;
+#if LWIP_NETIF_HOSTNAME
+  /* @todo: Initialize interface hostname */
+  /* netif_set_hostname(netif, "lwip"); */
+#endif /* LWIP_NETIF_HOSTNAME */
+  return ERR_OK;
+}
+
+
+/*
+ * sifup - Config the interface up and enable IP packets to pass.
+ */
+int
+sifup(int pd)
+{
+  PPPControl *pc = &pppControl[pd];
+  int st = 1;
+  
+  if (pd < 0 || pd >= NUM_PPP || !pc->openFlag) {
+    st = 0;
+    PPPDEBUG(LOG_WARNING, ("sifup[%d]: bad parms\n", pd));
+  } else {
+    netif_remove(&pc->netif);
+    if (netif_add(&pc->netif, &pc->addrs.our_ipaddr, &pc->addrs.netmask,
+                  &pc->addrs.his_ipaddr, (void *)(size_t)pd, pppifNetifInit, ip_input)) {
+      netif_set_up(&pc->netif);
+      pc->if_up = 1;
+      pc->errCode = PPPERR_NONE;
+
+      PPPDEBUG(LOG_DEBUG, ("sifup: unit %d: linkStatusCB=%p errCode=%d\n", pd, pc->linkStatusCB, pc->errCode));
+      if (pc->linkStatusCB) {
+        pc->linkStatusCB(pc->linkStatusCtx, pc->errCode, &pc->addrs);
+      }
+    } else {
+      st = 0;
+      PPPDEBUG(LOG_ERR, ("sifup[%d]: netif_add failed\n", pd));
+    }
+  }
+
+  return st;
+}
+
+/*
+ * sifnpmode - Set the mode for handling packets for a given NP.
+ */
+int
+sifnpmode(int u, int proto, enum NPmode mode)
+{
+  LWIP_UNUSED_ARG(u);
+  LWIP_UNUSED_ARG(proto);
+  LWIP_UNUSED_ARG(mode);
+  return 0;
+}
+
+/*
+ * sifdown - Config the interface down and disable IP.
+ */
+int
+sifdown(int pd)
+{
+  PPPControl *pc = &pppControl[pd];
+  int st = 1;
+  
+  if (pd < 0 || pd >= NUM_PPP || !pc->openFlag) {
+    st = 0;
+    PPPDEBUG(LOG_WARNING, ("sifdown[%d]: bad parms\n", pd));
+  } else {
+    pc->if_up = 0;
+    /* make sure the netif status callback is called */
+    netif_set_down(&pc->netif);
+    netif_remove(&pc->netif);
+    PPPDEBUG(LOG_DEBUG, ("sifdown: unit %d: linkStatusCB=%p errCode=%d\n", pd, pc->linkStatusCB, pc->errCode));
+    if (pc->linkStatusCB) {
+      pc->linkStatusCB(pc->linkStatusCtx, PPPERR_CONNECT, NULL);
+    }
+  }
+  return st;
+}
+
+/**
+ * sifaddr - Config the interface IP addresses and netmask.
+ * @param pd Interface unit ???
+ * @param o Our IP address ???
+ * @param h His IP address ???
+ * @param m IP subnet mask ???
+ * @param ns1 Primary DNS
+ * @param ns2 Secondary DNS
+ */
+int
+sifaddr( int pd, u32_t o, u32_t h, u32_t m, u32_t ns1, u32_t ns2)
+{
+  PPPControl *pc = &pppControl[pd];
+  int st = 1;
+  
+  if (pd < 0 || pd >= NUM_PPP || !pc->openFlag) {
+    st = 0;
+    PPPDEBUG(LOG_WARNING, ("sifup[%d]: bad parms\n", pd));
+  } else {
+    SMEMCPY(&pc->addrs.our_ipaddr, &o, sizeof(o));
+    SMEMCPY(&pc->addrs.his_ipaddr, &h, sizeof(h));
+    SMEMCPY(&pc->addrs.netmask, &m, sizeof(m));
+    SMEMCPY(&pc->addrs.dns1, &ns1, sizeof(ns1));
+    SMEMCPY(&pc->addrs.dns2, &ns2, sizeof(ns2));
+  }
+  return st;
+}
+
+/**
+ * cifaddr - Clear the interface IP addresses, and delete routes
+ * through the interface if possible.
+ * @param pd Interface unit ???
+ * @param o Our IP address ???
+ * @param h IP broadcast address ???
+ */
+int
+cifaddr( int pd, u32_t o, u32_t h)
+{
+  PPPControl *pc = &pppControl[pd];
+  int st = 1;
+  
+  LWIP_UNUSED_ARG(o);
+  LWIP_UNUSED_ARG(h);
+  if (pd < 0 || pd >= NUM_PPP || !pc->openFlag) {
+    st = 0;
+    PPPDEBUG(LOG_WARNING, ("sifup[%d]: bad parms\n", pd));
+  } else {
+    IP4_ADDR(&pc->addrs.our_ipaddr, 0,0,0,0);
+    IP4_ADDR(&pc->addrs.his_ipaddr, 0,0,0,0);
+    IP4_ADDR(&pc->addrs.netmask, 255,255,255,0);
+    IP4_ADDR(&pc->addrs.dns1, 0,0,0,0);
+    IP4_ADDR(&pc->addrs.dns2, 0,0,0,0);
+  }
+  return st;
+}
+
+/*
+ * sifdefaultroute - assign a default route through the address given.
+ */
+int
+sifdefaultroute(int pd, u32_t l, u32_t g)
+{
+  PPPControl *pc = &pppControl[pd];
+  int st = 1;
+
+  LWIP_UNUSED_ARG(l);
+  LWIP_UNUSED_ARG(g);
+
+  if (pd < 0 || pd >= NUM_PPP || !pc->openFlag) {
+    st = 0;
+    PPPDEBUG(LOG_WARNING, ("sifup[%d]: bad parms\n", pd));
+  } else {
+    netif_set_default(&pc->netif);
+  }
+
+  /* TODO: check how PPP handled the netMask, previously not set by ipSetDefault */
+
+  return st;
+}
+
+/*
+ * cifdefaultroute - delete a default route through the address given.
+ */
+int
+cifdefaultroute(int pd, u32_t l, u32_t g)
+{
+  PPPControl *pc = &pppControl[pd];
+  int st = 1;
+
+  LWIP_UNUSED_ARG(l);
+  LWIP_UNUSED_ARG(g);
+
+  if (pd < 0 || pd >= NUM_PPP || !pc->openFlag) {
+    st = 0;
+    PPPDEBUG(LOG_WARNING, ("sifup[%d]: bad parms\n", pd));
+  } else {
+    netif_set_default(NULL);
+  }
+
+  return st;
+}
+
+/**********************************/
+/*** LOCAL FUNCTION DEFINITIONS ***/
+/**********************************/
+
+#if PPPOS_SUPPORT && PPP_INPROC_OWNTHREAD
+/* The main PPP process function.  This implements the state machine according
+ * to section 4 of RFC 1661: The Point-To-Point Protocol. */
+static void
+pppInputThread(void *arg)
+{
+  int count;
+  PPPControlRx *pcrx = arg;
+
+#if !__LWIP_ORIG
+  do
+  {
+  sys_arch_mbox_fetch(&pppMbox, (void**)&pcrx, 0); //Wait indefinitely
+#endif
+
+  while (lcp_phase[pcrx->pd] != PHASE_DEAD) {
+    count = sio_read(pcrx->fd, pcrx->rxbuf, PPPOS_RX_BUFSIZE);
+    if(count > 0) {
+      pppInProc(pcrx, pcrx->rxbuf, count);
+    } else {
+      /* nothing received, give other tasks a chance to run */
+      sys_msleep(1);
+    }
+  }
+#if !__LWIP_ORIG
+  } while(1); //Never terminates
+#endif
+}
+#endif /* PPPOS_SUPPORT && PPP_INPROC_OWNTHREAD */
+
+#if PPPOE_SUPPORT
+
+void
+pppOverEthernetInitFailed(int pd)
+{
+  PPPControl* pc;
+
+  pppHup(pd);
+  pppStop(pd);
+
+  pc = &pppControl[pd];
+  pppoe_destroy(&pc->netif);
+  pc->openFlag = 0;
+
+  if(pc->linkStatusCB) {
+    pc->linkStatusCB(pc->linkStatusCtx, pc->errCode ? pc->errCode : PPPERR_PROTOCOL, NULL);
+  }
+}
+
+static void
+pppOverEthernetLinkStatusCB(int pd, int up)
+{
+  if(up) {
+    PPPDEBUG(LOG_INFO, ("pppOverEthernetLinkStatusCB: unit %d: Connecting\n", pd));
+    pppStart(pd);
+  } else {
+    pppOverEthernetInitFailed(pd);
+  }
+}
+#endif /* PPPOE_SUPPORT */
+
+struct pbuf *
+pppSingleBuf(struct pbuf *p)
+{
+  struct pbuf *q, *b;
+  u_char *pl;
+
+  if(p->tot_len == p->len) {
+    return p;
+  }
+
+  q = pbuf_alloc(PBUF_RAW, p->tot_len, PBUF_RAM);
+  if(!q) {
+    PPPDEBUG(LOG_ERR,
+             ("pppSingleBuf: unable to alloc new buf (%d)\n", p->tot_len));
+    return p; /* live dangerously */
+  }
+
+  for(b = p, pl = q->payload; b != NULL; b = b->next) {
+    MEMCPY(pl, b->payload, b->len);
+    pl += b->len;
+  }
+
+  pbuf_free(p);
+
+  return q;
+}
+
+struct pppInputHeader {
+  int unit;
+  u16_t proto;
+};
+
+/*
+ * Pass the processed input packet to the appropriate handler.
+ * This function and all handlers run in the context of the tcpip_thread
+ */
+static void
+pppInput(void *arg)
+{
+  struct pbuf *nb = (struct pbuf *)arg;
+  u16_t protocol;
+  int pd;
+
+  pd = ((struct pppInputHeader *)nb->payload)->unit;
+  protocol = ((struct pppInputHeader *)nb->payload)->proto;
+    
+  if(pbuf_header(nb, -(int)sizeof(struct pppInputHeader))) {
+    LWIP_ASSERT("pbuf_header failed\n", 0);
+    goto drop;
+  }
+
+  LINK_STATS_INC(link.recv);
+  snmp_inc_ifinucastpkts(&pppControl[pd].netif);
+  snmp_add_ifinoctets(&pppControl[pd].netif, nb->tot_len);
+
+  /*
+   * Toss all non-LCP packets unless LCP is OPEN.
+   * Until we get past the authentication phase, toss all packets
+   * except LCP, LQR and authentication packets.
+   */
+  if((lcp_phase[pd] <= PHASE_AUTHENTICATE) && (protocol != PPP_LCP)) {
+    if(!((protocol == PPP_LQR) || (protocol == PPP_PAP) || (protocol == PPP_CHAP)) ||
+        (lcp_phase[pd] != PHASE_AUTHENTICATE)) {
+      PPPDEBUG(LOG_INFO, ("pppInput: discarding proto 0x%"X16_F" in phase %d\n", protocol, lcp_phase[pd]));
+      goto drop;
+    }
+  }
+
+  switch(protocol) {
+    case PPP_VJC_COMP:      /* VJ compressed TCP */
+#if PPPOS_SUPPORT && VJ_SUPPORT
+      PPPDEBUG(LOG_INFO, ("pppInput[%d]: vj_comp in pbuf len=%d\n", pd, nb->len));
+      /*
+       * Clip off the VJ header and prepend the rebuilt TCP/IP header and
+       * pass the result to IP.
+       */
+      if ((vj_uncompress_tcp(&nb, &pppControl[pd].vjComp) >= 0) && (pppControl[pd].netif.input)) {
+        pppControl[pd].netif.input(nb, &pppControl[pd].netif);
+        return;
+      }
+      /* Something's wrong so drop it. */
+      PPPDEBUG(LOG_WARNING, ("pppInput[%d]: Dropping VJ compressed\n", pd));
+#else  /* PPPOS_SUPPORT && VJ_SUPPORT */
+      /* No handler for this protocol so drop the packet. */
+      PPPDEBUG(LOG_INFO, ("pppInput[%d]: drop VJ Comp in %d:%s\n", pd, nb->len, nb->payload));
+#endif /* PPPOS_SUPPORT && VJ_SUPPORT */
+      break;
+
+    case PPP_VJC_UNCOMP:    /* VJ uncompressed TCP */
+#if PPPOS_SUPPORT && VJ_SUPPORT
+      PPPDEBUG(LOG_INFO, ("pppInput[%d]: vj_un in pbuf len=%d\n", pd, nb->len));
+      /*
+       * Process the TCP/IP header for VJ header compression and then pass
+       * the packet to IP.
+       */
+      if ((vj_uncompress_uncomp(nb, &pppControl[pd].vjComp) >= 0) && pppControl[pd].netif.input) {
+        pppControl[pd].netif.input(nb, &pppControl[pd].netif);
+        return;
+      }
+      /* Something's wrong so drop it. */
+      PPPDEBUG(LOG_WARNING, ("pppInput[%d]: Dropping VJ uncompressed\n", pd));
+#else  /* PPPOS_SUPPORT && VJ_SUPPORT */
+      /* No handler for this protocol so drop the packet. */
+      PPPDEBUG(LOG_INFO,
+               ("pppInput[%d]: drop VJ UnComp in %d:.*H\n", 
+                pd, nb->len, LWIP_MIN(nb->len * 2, 40), nb->payload));
+#endif /* PPPOS_SUPPORT && VJ_SUPPORT */
+      break;
+
+    case PPP_IP:            /* Internet Protocol */
+      PPPDEBUG(LOG_INFO, ("pppInput[%d]: ip in pbuf len=%d\n", pd, nb->len));
+      if (pppControl[pd].netif.input) {
+        pppControl[pd].netif.input(nb, &pppControl[pd].netif);
+        return;
+      }
+      break;
+
+    default: {
+      struct protent *protp;
+      int i;
+
+      /*
+       * Upcall the proper protocol input routine.
+       */
+      for (i = 0; (protp = ppp_protocols[i]) != NULL; ++i) {
+        if (protp->protocol == protocol && protp->enabled_flag) {
+          PPPDEBUG(LOG_INFO, ("pppInput[%d]: %s len=%d\n", pd, protp->name, nb->len));
+          nb = pppSingleBuf(nb);
+          (*protp->input)(pd, nb->payload, nb->len);
+          PPPDEBUG(LOG_DETAIL, ("pppInput[%d]: packet processed\n", pd));
+          goto out;
+        }
+      }
+
+      /* No handler for this protocol so reject the packet. */
+      PPPDEBUG(LOG_INFO, ("pppInput[%d]: rejecting unsupported proto 0x%"X16_F" len=%d\n", pd, protocol, nb->len));
+      if (pbuf_header(nb, sizeof(protocol))) {
+        LWIP_ASSERT("pbuf_header failed\n", 0);
+        goto drop;
+      }
+#if BYTE_ORDER == LITTLE_ENDIAN
+      protocol = htons(protocol);
+#endif /* BYTE_ORDER == LITTLE_ENDIAN */
+      SMEMCPY(nb->payload, &protocol, sizeof(protocol));
+      lcp_sprotrej(pd, nb->payload, nb->len);
+    }
+    break;
+  }
+
+drop:
+  LINK_STATS_INC(link.drop);
+  snmp_inc_ifindiscards(&pppControl[pd].netif);
+
+out:
+  pbuf_free(nb);
+  return;
+}
+
+#if PPPOS_SUPPORT
+/*
+ * Drop the input packet.
+ */
+static void
+pppDrop(PPPControlRx *pcrx)
+{
+  if (pcrx->inHead != NULL) {
+#if 0
+    PPPDEBUG(LOG_INFO, ("pppDrop: %d:%.*H\n", pcrx->inHead->len, min(60, pcrx->inHead->len * 2), pcrx->inHead->payload));
+#endif
+    PPPDEBUG(LOG_INFO, ("pppDrop: pbuf len=%d, addr %p\n", pcrx->inHead->len, (void*)pcrx->inHead));
+    if (pcrx->inTail && (pcrx->inTail != pcrx->inHead)) {
+      pbuf_free(pcrx->inTail);
+    }
+    pbuf_free(pcrx->inHead);
+    pcrx->inHead = NULL;
+    pcrx->inTail = NULL;
+  }
+#if VJ_SUPPORT
+  vj_uncompress_err(&pppControl[pcrx->pd].vjComp);
+#endif /* VJ_SUPPORT */
+
+  LINK_STATS_INC(link.drop);
+  snmp_inc_ifindiscards(&pppControl[pcrx->pd].netif);
+}
+
+/** Pass received raw characters to PPPoS to be decoded. This function is
+ * thread-safe and can be called from a dedicated RX-thread or from a main-loop.
+ *
+ * @param pd PPP descriptor index, returned by pppOpen()
+ * @param data received data
+ * @param len length of received data
+ */
+void
+pppos_input(int pd, u_char* data, int len)
+{
+  pppInProc(&pppControl[pd].rx, data, len);
+}
+
+/**
+ * Process a received octet string.
+ */
+static void
+pppInProc(PPPControlRx *pcrx, u_char *s, int l)
+{
+  struct pbuf *nextNBuf;
+  u_char curChar;
+  u_char escaped;
+  SYS_ARCH_DECL_PROTECT(lev);
+
+  PPPDEBUG(LOG_DEBUG, ("pppInProc[%d]: got %d bytes\n", pcrx->pd, l));
+  while (l-- > 0) {
+    curChar = *s++;
+
+    SYS_ARCH_PROTECT(lev);
+    escaped = ESCAPE_P(pcrx->inACCM, curChar);
+    SYS_ARCH_UNPROTECT(lev);
+    /* Handle special characters. */
+    if (escaped) {
+      /* Check for escape sequences. */
+      /* XXX Note that this does not handle an escaped 0x5d character which
+       * would appear as an escape character.  Since this is an ASCII ']'
+       * and there is no reason that I know of to escape it, I won't complicate
+       * the code to handle this case. GLL */
+      if (curChar == PPP_ESCAPE) {
+        pcrx->inEscaped = 1;
+      /* Check for the flag character. */
+      } else if (curChar == PPP_FLAG) {
+        /* If this is just an extra flag character, ignore it. */
+        if (pcrx->inState <= PDADDRESS) {
+          /* ignore it */;
+        /* If we haven't received the packet header, drop what has come in. */
+        } else if (pcrx->inState < PDDATA) {
+          PPPDEBUG(LOG_WARNING,
+                   ("pppInProc[%d]: Dropping incomplete packet %d\n", 
+                    pcrx->pd, pcrx->inState));
+          LINK_STATS_INC(link.lenerr);
+          pppDrop(pcrx);
+        /* If the fcs is invalid, drop the packet. */
+        } else if (pcrx->inFCS != PPP_GOODFCS) {
+          PPPDEBUG(LOG_INFO,
+                   ("pppInProc[%d]: Dropping bad fcs 0x%"X16_F" proto=0x%"X16_F"\n", 
+                    pcrx->pd, pcrx->inFCS, pcrx->inProtocol));
+          /* Note: If you get lots of these, check for UART frame errors or try different baud rate */
+          LINK_STATS_INC(link.chkerr);
+          pppDrop(pcrx);
+        /* Otherwise it's a good packet so pass it on. */
+        } else {
+          struct pbuf *inp;
+          /* Trim off the checksum. */
+          if(pcrx->inTail->len >= 2) {
+            pcrx->inTail->len -= 2;
+
+            pcrx->inTail->tot_len = pcrx->inTail->len;
+            if (pcrx->inTail != pcrx->inHead) {
+              pbuf_cat(pcrx->inHead, pcrx->inTail);
+            }
+          } else {
+            pcrx->inTail->tot_len = pcrx->inTail->len;
+            if (pcrx->inTail != pcrx->inHead) {
+              pbuf_cat(pcrx->inHead, pcrx->inTail);
+            }
+
+            pbuf_realloc(pcrx->inHead, pcrx->inHead->tot_len - 2);
+          }
+
+          /* Dispatch the packet thereby consuming it. */
+          inp = pcrx->inHead;
+          /* Packet consumed, release our references. */
+          pcrx->inHead = NULL;
+          pcrx->inTail = NULL;
+#if PPP_INPROC_MULTITHREADED
+          if(tcpip_callback_with_block(pppInput, inp, 0) != ERR_OK) {
+            PPPDEBUG(LOG_ERR, ("pppInProc[%d]: tcpip_callback() failed, dropping packet\n", pcrx->pd));
+            pbuf_free(inp);
+            LINK_STATS_INC(link.drop);
+            snmp_inc_ifindiscards(&pppControl[pcrx->pd].netif);
+          }
+#else /* PPP_INPROC_MULTITHREADED */
+          pppInput(inp);
+#endif /* PPP_INPROC_MULTITHREADED */
+        }
+
+        /* Prepare for a new packet. */
+        pcrx->inFCS = PPP_INITFCS;
+        pcrx->inState = PDADDRESS;
+        pcrx->inEscaped = 0;
+      /* Other characters are usually control characters that may have
+       * been inserted by the physical layer so here we just drop them. */
+      } else {
+        PPPDEBUG(LOG_WARNING,
+                 ("pppInProc[%d]: Dropping ACCM char <%d>\n", pcrx->pd, curChar));
+      }
+    /* Process other characters. */
+    } else {
+      /* Unencode escaped characters. */
+      if (pcrx->inEscaped) {
+        pcrx->inEscaped = 0;
+        curChar ^= PPP_TRANS;
+      }
+
+      /* Process character relative to current state. */
+      switch(pcrx->inState) {
+        case PDIDLE:                    /* Idle state - waiting. */
+          /* Drop the character if it's not 0xff
+           * we would have processed a flag character above. */
+          if (curChar != PPP_ALLSTATIONS) {
+            break;
+          }
+
+        /* Fall through */
+        case PDSTART:                   /* Process start flag. */
+          /* Prepare for a new packet. */
+          pcrx->inFCS = PPP_INITFCS;
+
+        /* Fall through */
+        case PDADDRESS:                 /* Process address field. */
+          if (curChar == PPP_ALLSTATIONS) {
+            pcrx->inState = PDCONTROL;
+            break;
+          }
+          /* Else assume compressed address and control fields so
+           * fall through to get the protocol... */
+        case PDCONTROL:                 /* Process control field. */
+          /* If we don't get a valid control code, restart. */
+          if (curChar == PPP_UI) {
+            pcrx->inState = PDPROTOCOL1;
+            break;
+          }
+#if 0
+          else {
+            PPPDEBUG(LOG_WARNING,
+                     ("pppInProc[%d]: Invalid control <%d>\n", pcrx->pd, curChar));
+            pcrx->inState = PDSTART;
+          }
+#endif
+        case PDPROTOCOL1:               /* Process protocol field 1. */
+          /* If the lower bit is set, this is the end of the protocol
+           * field. */
+          if (curChar & 1) {
+            pcrx->inProtocol = curChar;
+            pcrx->inState = PDDATA;
+          } else {
+            pcrx->inProtocol = (u_int)curChar << 8;
+            pcrx->inState = PDPROTOCOL2;
+          }
+          break;
+        case PDPROTOCOL2:               /* Process protocol field 2. */
+          pcrx->inProtocol |= curChar;
+          pcrx->inState = PDDATA;
+          break;
+        case PDDATA:                    /* Process data byte. */
+          /* Make space to receive processed data. */
+          if (pcrx->inTail == NULL || pcrx->inTail->len == PBUF_POOL_BUFSIZE) {
+            if (pcrx->inTail != NULL) {
+              pcrx->inTail->tot_len = pcrx->inTail->len;
+              if (pcrx->inTail != pcrx->inHead) {
+                pbuf_cat(pcrx->inHead, pcrx->inTail);
+                /* give up the inTail reference now */
+                pcrx->inTail = NULL;
+              }
+            }
+            /* If we haven't started a packet, we need a packet header. */
+            nextNBuf = pbuf_alloc(PBUF_RAW, 0, PBUF_POOL);
+            if (nextNBuf == NULL) {
+              /* No free buffers.  Drop the input packet and let the
+               * higher layers deal with it.  Continue processing
+               * the received pbuf chain in case a new packet starts. */
+              PPPDEBUG(LOG_ERR, ("pppInProc[%d]: NO FREE MBUFS!\n", pcrx->pd));
+              LINK_STATS_INC(link.memerr);
+              pppDrop(pcrx);
+              pcrx->inState = PDSTART;  /* Wait for flag sequence. */
+              break;
+            }
+            if (pcrx->inHead == NULL) {
+              struct pppInputHeader *pih = nextNBuf->payload;
+
+              pih->unit = pcrx->pd;
+              pih->proto = pcrx->inProtocol;
+
+              nextNBuf->len += sizeof(*pih);
+
+              pcrx->inHead = nextNBuf;
+            }
+            pcrx->inTail = nextNBuf;
+          }
+          /* Load character into buffer. */
+          ((u_char*)pcrx->inTail->payload)[pcrx->inTail->len++] = curChar;
+          break;
+      }
+
+      /* update the frame check sequence number. */
+      pcrx->inFCS = PPP_FCS(pcrx->inFCS, curChar);
+    }
+  } /* while (l-- > 0), all bytes processed */
+
+  avRandomize();
+}
+#endif /* PPPOS_SUPPORT */
+
+#if PPPOE_SUPPORT
+void
+pppInProcOverEthernet(int pd, struct pbuf *pb)
+{
+  struct pppInputHeader *pih;
+  u16_t inProtocol;
+
+  if(pb->len < sizeof(inProtocol)) {
+    PPPDEBUG(LOG_ERR, ("pppInProcOverEthernet: too small for protocol field\n"));
+    goto drop;
+  }
+
+  inProtocol = (((u8_t *)pb->payload)[0] << 8) | ((u8_t*)pb->payload)[1];
+
+  /* make room for pppInputHeader - should not fail */
+  if (pbuf_header(pb, sizeof(*pih) - sizeof(inProtocol)) != 0) {
+    PPPDEBUG(LOG_ERR, ("pppInProcOverEthernet: could not allocate room for header\n"));
+    goto drop;
+  }
+
+  pih = pb->payload;
+
+  pih->unit = pd;
+  pih->proto = inProtocol;
+
+  /* Dispatch the packet thereby consuming it. */
+  pppInput(pb);
+  return;
+
+drop:
+  LINK_STATS_INC(link.drop);
+  snmp_inc_ifindiscards(&pppControl[pd].netif);
+  pbuf_free(pb);
+  return;
+}
+#endif /* PPPOE_SUPPORT */
+
+#if LWIP_NETIF_STATUS_CALLBACK
+/** Set the status callback of a PPP's netif
+ *
+ * @param pd The PPP descriptor returned by pppOpen()
+ * @param status_callback pointer to the status callback function
+ *
+ * @see netif_set_status_callback
+ */
+void
+ppp_set_netif_statuscallback(int pd, netif_status_callback_fn status_callback)
+{
+  netif_set_status_callback(&pppControl[pd].netif, status_callback); 
+}
+#endif /* LWIP_NETIF_STATUS_CALLBACK */
+
+#if LWIP_NETIF_LINK_CALLBACK
+/** Set the link callback of a PPP's netif
+ *
+ * @param pd The PPP descriptor returned by pppOpen()
+ * @param link_callback pointer to the link callback function
+ *
+ * @see netif_set_link_callback
+ */
+void
+ppp_set_netif_linkcallback(int pd, netif_status_callback_fn link_callback)
+{
+  netif_set_link_callback(&pppControl[pd].netif, link_callback); 
+}
+#endif /* LWIP_NETIF_LINK_CALLBACK */
+
+#endif /* PPP_SUPPORT */