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Posted to commits@mynewt.apache.org by ma...@apache.org on 2016/09/30 00:30:50 UTC

[07/51] [abbrv] [partial] incubator-mynewt-core git commit: net/ip/lwip_base; LwIP.

http://git-wip-us.apache.org/repos/asf/incubator-mynewt-core/blob/f5a0f2a0/net/ip/lwip_base/src/netif/ppp/ccp.c
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diff --git a/net/ip/lwip_base/src/netif/ppp/ccp.c b/net/ip/lwip_base/src/netif/ppp/ccp.c
new file mode 100644
index 0000000..f8519eb
--- /dev/null
+++ b/net/ip/lwip_base/src/netif/ppp/ccp.c
@@ -0,0 +1,1740 @@
+/*
+ * ccp.c - PPP Compression Control Protocol.
+ *
+ * Copyright (c) 1994-2002 Paul Mackerras. 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. The name(s) of the authors of this software must not be used to
+ *    endorse or promote products derived from this software without
+ *    prior written permission.
+ *
+ * 3. Redistributions of any form whatsoever must retain the following
+ *    acknowledgment:
+ *    "This product includes software developed by Paul Mackerras
+ *     <pa...@samba.org>".
+ *
+ * THE AUTHORS OF THIS SOFTWARE DISCLAIM ALL WARRANTIES WITH REGARD TO
+ * THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
+ * AND FITNESS, IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY
+ * SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN
+ * AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING
+ * OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#include "netif/ppp/ppp_opts.h"
+#if PPP_SUPPORT && CCP_SUPPORT  /* don't build if not configured for use in lwipopts.h */
+
+#include <stdlib.h>
+#include <string.h>
+
+#include "netif/ppp/ppp_impl.h"
+
+#include "netif/ppp/fsm.h"
+#include "netif/ppp/ccp.h"
+
+#if MPPE_SUPPORT
+#include "netif/ppp/lcp.h"	/* lcp_close(), lcp_fsm */
+#include "netif/ppp/mppe.h"	/* mppe_init() */
+#endif /* MPPE_SUPPORT */
+
+/*
+ * Unfortunately there is a bug in zlib which means that using a
+ * size of 8 (window size = 256) for Deflate compression will cause
+ * buffer overruns and kernel crashes in the deflate module.
+ * Until this is fixed we only accept sizes in the range 9 .. 15.
+ * Thanks to James Carlson for pointing this out.
+ */
+#define DEFLATE_MIN_WORKS	9
+
+/*
+ * Command-line options.
+ */
+#if PPP_OPTIONS
+static int setbsdcomp (char **);
+static int setdeflate (char **);
+static char bsd_value[8];
+static char deflate_value[8];
+
+/*
+ * Option variables.
+ */
+#if MPPE_SUPPORT
+bool refuse_mppe_stateful = 1;		/* Allow stateful mode? */
+#endif /* MPPE_SUPPORT */
+
+static option_t ccp_option_list[] = {
+    { "noccp", o_bool, &ccp_protent.enabled_flag,
+      "Disable CCP negotiation" },
+    { "-ccp", o_bool, &ccp_protent.enabled_flag,
+      "Disable CCP negotiation", OPT_ALIAS },
+
+    { "bsdcomp", o_special, (void *)setbsdcomp,
+      "Request BSD-Compress packet compression",
+      OPT_PRIO | OPT_A2STRVAL | OPT_STATIC, bsd_value },
+    { "nobsdcomp", o_bool, &ccp_wantoptions[0].bsd_compress,
+      "don't allow BSD-Compress", OPT_PRIOSUB | OPT_A2CLR,
+      &ccp_allowoptions[0].bsd_compress },
+    { "-bsdcomp", o_bool, &ccp_wantoptions[0].bsd_compress,
+      "don't allow BSD-Compress", OPT_ALIAS | OPT_PRIOSUB | OPT_A2CLR,
+      &ccp_allowoptions[0].bsd_compress },
+
+    { "deflate", o_special, (void *)setdeflate,
+      "request Deflate compression",
+      OPT_PRIO | OPT_A2STRVAL | OPT_STATIC, deflate_value },
+    { "nodeflate", o_bool, &ccp_wantoptions[0].deflate,
+      "don't allow Deflate compression", OPT_PRIOSUB | OPT_A2CLR,
+      &ccp_allowoptions[0].deflate },
+    { "-deflate", o_bool, &ccp_wantoptions[0].deflate,
+      "don't allow Deflate compression", OPT_ALIAS | OPT_PRIOSUB | OPT_A2CLR,
+      &ccp_allowoptions[0].deflate },
+
+    { "nodeflatedraft", o_bool, &ccp_wantoptions[0].deflate_draft,
+      "don't use draft deflate #", OPT_A2COPY,
+      &ccp_allowoptions[0].deflate_draft },
+
+    { "predictor1", o_bool, &ccp_wantoptions[0].predictor_1,
+      "request Predictor-1", OPT_PRIO | 1 },
+    { "nopredictor1", o_bool, &ccp_wantoptions[0].predictor_1,
+      "don't allow Predictor-1", OPT_PRIOSUB | OPT_A2CLR,
+      &ccp_allowoptions[0].predictor_1 },
+    { "-predictor1", o_bool, &ccp_wantoptions[0].predictor_1,
+      "don't allow Predictor-1", OPT_ALIAS | OPT_PRIOSUB | OPT_A2CLR,
+      &ccp_allowoptions[0].predictor_1 },
+
+#if MPPE_SUPPORT
+    /* MPPE options are symmetrical ... we only set wantoptions here */
+    { "require-mppe", o_bool, &ccp_wantoptions[0].mppe,
+      "require MPPE encryption",
+      OPT_PRIO | MPPE_OPT_40 | MPPE_OPT_128 },
+    { "+mppe", o_bool, &ccp_wantoptions[0].mppe,
+      "require MPPE encryption",
+      OPT_ALIAS | OPT_PRIO | MPPE_OPT_40 | MPPE_OPT_128 },
+    { "nomppe", o_bool, &ccp_wantoptions[0].mppe,
+      "don't allow MPPE encryption", OPT_PRIO },
+    { "-mppe", o_bool, &ccp_wantoptions[0].mppe,
+      "don't allow MPPE encryption", OPT_ALIAS | OPT_PRIO },
+
+    /* We use ccp_allowoptions[0].mppe as a junk var ... it is reset later */
+    { "require-mppe-40", o_bool, &ccp_allowoptions[0].mppe,
+      "require MPPE 40-bit encryption", OPT_PRIO | OPT_A2OR | MPPE_OPT_40,
+      &ccp_wantoptions[0].mppe },
+    { "+mppe-40", o_bool, &ccp_allowoptions[0].mppe,
+      "require MPPE 40-bit encryption", OPT_PRIO | OPT_A2OR | MPPE_OPT_40,
+      &ccp_wantoptions[0].mppe },
+    { "nomppe-40", o_bool, &ccp_allowoptions[0].mppe,
+      "don't allow MPPE 40-bit encryption",
+      OPT_PRIOSUB | OPT_A2CLRB | MPPE_OPT_40, &ccp_wantoptions[0].mppe },
+    { "-mppe-40", o_bool, &ccp_allowoptions[0].mppe,
+      "don't allow MPPE 40-bit encryption",
+      OPT_ALIAS | OPT_PRIOSUB | OPT_A2CLRB | MPPE_OPT_40,
+      &ccp_wantoptions[0].mppe },
+
+    { "require-mppe-128", o_bool, &ccp_allowoptions[0].mppe,
+      "require MPPE 128-bit encryption", OPT_PRIO | OPT_A2OR | MPPE_OPT_128,
+      &ccp_wantoptions[0].mppe },
+    { "+mppe-128", o_bool, &ccp_allowoptions[0].mppe,
+      "require MPPE 128-bit encryption",
+      OPT_ALIAS | OPT_PRIO | OPT_A2OR | MPPE_OPT_128,
+      &ccp_wantoptions[0].mppe },
+    { "nomppe-128", o_bool, &ccp_allowoptions[0].mppe,
+      "don't allow MPPE 128-bit encryption",
+      OPT_PRIOSUB | OPT_A2CLRB | MPPE_OPT_128, &ccp_wantoptions[0].mppe },
+    { "-mppe-128", o_bool, &ccp_allowoptions[0].mppe,
+      "don't allow MPPE 128-bit encryption",
+      OPT_ALIAS | OPT_PRIOSUB | OPT_A2CLRB | MPPE_OPT_128,
+      &ccp_wantoptions[0].mppe },
+
+    /* strange one; we always request stateless, but will we allow stateful? */
+    { "mppe-stateful", o_bool, &refuse_mppe_stateful,
+      "allow MPPE stateful mode", OPT_PRIO },
+    { "nomppe-stateful", o_bool, &refuse_mppe_stateful,
+      "disallow MPPE stateful mode", OPT_PRIO | 1 },
+#endif /* MPPE_SUPPORT */
+
+    { NULL }
+};
+#endif /* PPP_OPTIONS */
+
+/*
+ * Protocol entry points from main code.
+ */
+static void ccp_init(ppp_pcb *pcb);
+static void ccp_open(ppp_pcb *pcb);
+static void ccp_close(ppp_pcb *pcb, const char *reason);
+static void ccp_lowerup(ppp_pcb *pcb);
+static void ccp_lowerdown(ppp_pcb *pcb);
+static void ccp_input(ppp_pcb *pcb, u_char *pkt, int len);
+static void ccp_protrej(ppp_pcb *pcb);
+#if PRINTPKT_SUPPORT
+static int ccp_printpkt(const u_char *p, int plen, void (*printer) (void *, const char *, ...), void *arg);
+#endif /* PRINTPKT_SUPPORT */
+#if PPP_DATAINPUT
+static void ccp_datainput(ppp_pcb *pcb, u_char *pkt, int len);
+#endif /* PPP_DATAINPUT */
+
+const struct protent ccp_protent = {
+    PPP_CCP,
+    ccp_init,
+    ccp_input,
+    ccp_protrej,
+    ccp_lowerup,
+    ccp_lowerdown,
+    ccp_open,
+    ccp_close,
+#if PRINTPKT_SUPPORT
+    ccp_printpkt,
+#endif /* PRINTPKT_SUPPORT */
+#if PPP_DATAINPUT
+    ccp_datainput,
+#endif /* PPP_DATAINPUT */
+#if PRINTPKT_SUPPORT
+    "CCP",
+    "Compressed",
+#endif /* PRINTPKT_SUPPORT */
+#if PPP_OPTIONS
+    ccp_option_list,
+    NULL,
+#endif /* PPP_OPTIONS */
+#if DEMAND_SUPPORT
+    NULL,
+    NULL
+#endif /* DEMAND_SUPPORT */
+};
+
+/*
+ * Callbacks for fsm code.
+ */
+static void ccp_resetci (fsm *);
+static int  ccp_cilen (fsm *);
+static void ccp_addci (fsm *, u_char *, int *);
+static int  ccp_ackci (fsm *, u_char *, int);
+static int  ccp_nakci (fsm *, u_char *, int, int);
+static int  ccp_rejci (fsm *, u_char *, int);
+static int  ccp_reqci (fsm *, u_char *, int *, int);
+static void ccp_up (fsm *);
+static void ccp_down (fsm *);
+static int  ccp_extcode (fsm *, int, int, u_char *, int);
+static void ccp_rack_timeout (void *);
+static const char *method_name (ccp_options *, ccp_options *);
+
+static const fsm_callbacks ccp_callbacks = {
+    ccp_resetci,
+    ccp_cilen,
+    ccp_addci,
+    ccp_ackci,
+    ccp_nakci,
+    ccp_rejci,
+    ccp_reqci,
+    ccp_up,
+    ccp_down,
+    NULL,
+    NULL,
+    NULL,
+    NULL,
+    ccp_extcode,
+    "CCP"
+};
+
+/*
+ * Do we want / did we get any compression?
+ */
+static int ccp_anycompress(ccp_options *opt) {
+    return (0
+#if DEFLATE_SUPPORT
+	|| (opt)->deflate
+#endif /* DEFLATE_SUPPORT */
+#if BSDCOMPRESS_SUPPORT
+	|| (opt)->bsd_compress
+#endif /* BSDCOMPRESS_SUPPORT */
+#if PREDICTOR_SUPPORT
+	|| (opt)->predictor_1 || (opt)->predictor_2
+#endif /* PREDICTOR_SUPPORT */
+#if MPPE_SUPPORT
+	|| (opt)->mppe
+#endif /* MPPE_SUPPORT */
+	);
+}
+
+/*
+ * Local state (mainly for handling reset-reqs and reset-acks).
+ */
+#define RACK_PENDING	1	/* waiting for reset-ack */
+#define RREQ_REPEAT	2	/* send another reset-req if no reset-ack */
+
+#define RACKTIMEOUT	1	/* second */
+
+#if PPP_OPTIONS
+/*
+ * Option parsing
+ */
+static int
+setbsdcomp(argv)
+    char **argv;
+{
+    int rbits, abits;
+    char *str, *endp;
+
+    str = *argv;
+    abits = rbits = strtol(str, &endp, 0);
+    if (endp != str && *endp == ',') {
+	str = endp + 1;
+	abits = strtol(str, &endp, 0);
+    }
+    if (*endp != 0 || endp == str) {
+	option_error("invalid parameter '%s' for bsdcomp option", *argv);
+	return 0;
+    }
+    if ((rbits != 0 && (rbits < BSD_MIN_BITS || rbits > BSD_MAX_BITS))
+	|| (abits != 0 && (abits < BSD_MIN_BITS || abits > BSD_MAX_BITS))) {
+	option_error("bsdcomp option values must be 0 or %d .. %d",
+		     BSD_MIN_BITS, BSD_MAX_BITS);
+	return 0;
+    }
+    if (rbits > 0) {
+	ccp_wantoptions[0].bsd_compress = 1;
+	ccp_wantoptions[0].bsd_bits = rbits;
+    } else
+	ccp_wantoptions[0].bsd_compress = 0;
+    if (abits > 0) {
+	ccp_allowoptions[0].bsd_compress = 1;
+	ccp_allowoptions[0].bsd_bits = abits;
+    } else
+	ccp_allowoptions[0].bsd_compress = 0;
+    ppp_slprintf(bsd_value, sizeof(bsd_value),
+	     rbits == abits? "%d": "%d,%d", rbits, abits);
+
+    return 1;
+}
+
+static int
+setdeflate(argv)
+    char **argv;
+{
+    int rbits, abits;
+    char *str, *endp;
+
+    str = *argv;
+    abits = rbits = strtol(str, &endp, 0);
+    if (endp != str && *endp == ',') {
+	str = endp + 1;
+	abits = strtol(str, &endp, 0);
+    }
+    if (*endp != 0 || endp == str) {
+	option_error("invalid parameter '%s' for deflate option", *argv);
+	return 0;
+    }
+    if ((rbits != 0 && (rbits < DEFLATE_MIN_SIZE || rbits > DEFLATE_MAX_SIZE))
+	|| (abits != 0 && (abits < DEFLATE_MIN_SIZE
+			  || abits > DEFLATE_MAX_SIZE))) {
+	option_error("deflate option values must be 0 or %d .. %d",
+		     DEFLATE_MIN_SIZE, DEFLATE_MAX_SIZE);
+	return 0;
+    }
+    if (rbits == DEFLATE_MIN_SIZE || abits == DEFLATE_MIN_SIZE) {
+	if (rbits == DEFLATE_MIN_SIZE)
+	    rbits = DEFLATE_MIN_WORKS;
+	if (abits == DEFLATE_MIN_SIZE)
+	    abits = DEFLATE_MIN_WORKS;
+	warn("deflate option value of %d changed to %d to avoid zlib bug",
+	     DEFLATE_MIN_SIZE, DEFLATE_MIN_WORKS);
+    }
+    if (rbits > 0) {
+	ccp_wantoptions[0].deflate = 1;
+	ccp_wantoptions[0].deflate_size = rbits;
+    } else
+	ccp_wantoptions[0].deflate = 0;
+    if (abits > 0) {
+	ccp_allowoptions[0].deflate = 1;
+	ccp_allowoptions[0].deflate_size = abits;
+    } else
+	ccp_allowoptions[0].deflate = 0;
+    ppp_slprintf(deflate_value, sizeof(deflate_value),
+	     rbits == abits? "%d": "%d,%d", rbits, abits);
+
+    return 1;
+}
+#endif /* PPP_OPTIONS */
+
+/*
+ * ccp_init - initialize CCP.
+ */
+static void ccp_init(ppp_pcb *pcb) {
+    fsm *f = &pcb->ccp_fsm;
+
+    f->pcb = pcb;
+    f->protocol = PPP_CCP;
+    f->callbacks = &ccp_callbacks;
+    fsm_init(f);
+
+#if 0 /* Not necessary, everything is cleared in ppp_new() */
+    memset(wo, 0, sizeof(*wo));
+    memset(go, 0, sizeof(*go));
+    memset(ao, 0, sizeof(*ao));
+    memset(ho, 0, sizeof(*ho));
+#endif /* 0 */
+
+#if DEFLATE_SUPPORT
+    wo->deflate = 1;
+    wo->deflate_size = DEFLATE_MAX_SIZE;
+    wo->deflate_correct = 1;
+    wo->deflate_draft = 1;
+    ao->deflate = 1;
+    ao->deflate_size = DEFLATE_MAX_SIZE;
+    ao->deflate_correct = 1;
+    ao->deflate_draft = 1;
+#endif /* DEFLATE_SUPPORT */
+
+#if BSDCOMPRESS_SUPPORT
+    wo->bsd_compress = 1;
+    wo->bsd_bits = BSD_MAX_BITS;
+    ao->bsd_compress = 1;
+    ao->bsd_bits = BSD_MAX_BITS;
+#endif /* BSDCOMPRESS_SUPPORT */
+
+#if PREDICTOR_SUPPORT
+    ao->predictor_1 = 1;
+#endif /* PREDICTOR_SUPPORT */
+}
+
+/*
+ * ccp_open - CCP is allowed to come up.
+ */
+static void ccp_open(ppp_pcb *pcb) {
+    fsm *f = &pcb->ccp_fsm;
+    ccp_options *go = &pcb->ccp_gotoptions;
+
+    if (f->state != PPP_FSM_OPENED)
+	ccp_set(pcb, 1, 0, 0, 0);
+
+    /*
+     * Find out which compressors the kernel supports before
+     * deciding whether to open in silent mode.
+     */
+    ccp_resetci(f);
+    if (!ccp_anycompress(go))
+	f->flags |= OPT_SILENT;
+
+    fsm_open(f);
+}
+
+/*
+ * ccp_close - Terminate CCP.
+ */
+static void ccp_close(ppp_pcb *pcb, const char *reason) {
+    fsm *f = &pcb->ccp_fsm;
+    ccp_set(pcb, 0, 0, 0, 0);
+    fsm_close(f, reason);
+}
+
+/*
+ * ccp_lowerup - we may now transmit CCP packets.
+ */
+static void ccp_lowerup(ppp_pcb *pcb) {
+    fsm *f = &pcb->ccp_fsm;
+    fsm_lowerup(f);
+}
+
+/*
+ * ccp_lowerdown - we may not transmit CCP packets.
+ */
+static void ccp_lowerdown(ppp_pcb *pcb) {
+    fsm *f = &pcb->ccp_fsm;
+    fsm_lowerdown(f);
+}
+
+/*
+ * ccp_input - process a received CCP packet.
+ */
+static void ccp_input(ppp_pcb *pcb, u_char *p, int len) {
+    fsm *f = &pcb->ccp_fsm;
+    ccp_options *go = &pcb->ccp_gotoptions;
+    int oldstate;
+
+    /*
+     * Check for a terminate-request so we can print a message.
+     */
+    oldstate = f->state;
+    fsm_input(f, p, len);
+    if (oldstate == PPP_FSM_OPENED && p[0] == TERMREQ && f->state != PPP_FSM_OPENED) {
+	ppp_notice("Compression disabled by peer.");
+#if MPPE_SUPPORT
+	if (go->mppe) {
+	    ppp_error("MPPE disabled, closing LCP");
+	    lcp_close(pcb, "MPPE disabled by peer");
+	}
+#endif /* MPPE_SUPPORT */
+    }
+
+    /*
+     * If we get a terminate-ack and we're not asking for compression,
+     * close CCP.
+     */
+    if (oldstate == PPP_FSM_REQSENT && p[0] == TERMACK
+	&& !ccp_anycompress(go))
+	ccp_close(pcb, "No compression negotiated");
+}
+
+/*
+ * Handle a CCP-specific code.
+ */
+static int ccp_extcode(fsm *f, int code, int id, u_char *p, int len) {
+    ppp_pcb *pcb = f->pcb;
+    LWIP_UNUSED_ARG(p);
+    LWIP_UNUSED_ARG(len);
+
+    switch (code) {
+    case CCP_RESETREQ:
+	if (f->state != PPP_FSM_OPENED)
+	    break;
+	ccp_reset_comp(pcb);
+	/* send a reset-ack, which the transmitter will see and
+	   reset its compression state. */
+	fsm_sdata(f, CCP_RESETACK, id, NULL, 0);
+	break;
+
+    case CCP_RESETACK:
+	if ((pcb->ccp_localstate & RACK_PENDING) && id == f->reqid) {
+	    pcb->ccp_localstate &= ~(RACK_PENDING | RREQ_REPEAT);
+	    UNTIMEOUT(ccp_rack_timeout, f);
+	    ccp_reset_decomp(pcb);
+	}
+	break;
+
+    default:
+	return 0;
+    }
+
+    return 1;
+}
+
+/*
+ * ccp_protrej - peer doesn't talk CCP.
+ */
+static void ccp_protrej(ppp_pcb *pcb) {
+    fsm *f = &pcb->ccp_fsm;
+#if MPPE_SUPPORT
+    ccp_options *go = &pcb->ccp_gotoptions;
+#endif /* MPPE_SUPPORT */
+
+    ccp_set(pcb, 0, 0, 0, 0);
+    fsm_lowerdown(f);
+
+#if MPPE_SUPPORT
+    if (go->mppe) {
+	ppp_error("MPPE required but peer negotiation failed");
+	lcp_close(pcb, "MPPE required but peer negotiation failed");
+    }
+#endif /* MPPE_SUPPORT */
+
+}
+
+/*
+ * ccp_resetci - initialize at start of negotiation.
+ */
+static void ccp_resetci(fsm *f) {
+    ppp_pcb *pcb = f->pcb;
+    ccp_options *go = &pcb->ccp_gotoptions;
+    ccp_options *wo = &pcb->ccp_wantoptions;
+#if MPPE_SUPPORT
+    ccp_options *ao = &pcb->ccp_allowoptions;
+#endif /* MPPE_SUPPORT */
+#if DEFLATE_SUPPORT || BSDCOMPRESS_SUPPORT || PREDICTOR_SUPPORT
+    u_char opt_buf[CCP_MAX_OPTION_LENGTH];
+#endif /* DEFLATE_SUPPORT || BSDCOMPRESS_SUPPORT || PREDICTOR_SUPPORT */
+#if DEFLATE_SUPPORT || BSDCOMPRESS_SUPPORT
+    int res;
+#endif /* DEFLATE_SUPPORT || BSDCOMPRESS_SUPPORT */
+
+#if MPPE_SUPPORT
+    if (pcb->settings.require_mppe) {
+	wo->mppe = ao->mppe =
+		    (pcb->settings.refuse_mppe_40 ? 0 : MPPE_OPT_40)
+		  | (pcb->settings.refuse_mppe_128 ? 0 : MPPE_OPT_128);
+    }
+#endif /* MPPE_SUPPORT */
+
+    *go = *wo;
+    pcb->ccp_all_rejected = 0;
+
+#if MPPE_SUPPORT
+    if (go->mppe) {
+	int auth_mschap_bits = pcb->auth_done;
+	int numbits;
+
+	/*
+	 * Start with a basic sanity check: mschap[v2] auth must be in
+	 * exactly one direction.  RFC 3079 says that the keys are
+	 * 'derived from the credentials of the peer that initiated the call',
+	 * however the PPP protocol doesn't have such a concept, and pppd
+	 * cannot get this info externally.  Instead we do the best we can.
+	 * NB: If MPPE is required, all other compression opts are invalid.
+	 *     So, we return right away if we can't do it.
+	 */
+
+	/* Leave only the mschap auth bits set */
+	auth_mschap_bits &= (CHAP_MS_WITHPEER  | CHAP_MS_PEER |
+			     CHAP_MS2_WITHPEER | CHAP_MS2_PEER);
+	/* Count the mschap auths */
+	auth_mschap_bits >>= CHAP_MS_SHIFT;
+	numbits = 0;
+	do {
+	    numbits += auth_mschap_bits & 1;
+	    auth_mschap_bits >>= 1;
+	} while (auth_mschap_bits);
+	if (numbits > 1) {
+	    ppp_error("MPPE required, but auth done in both directions.");
+	    lcp_close(pcb, "MPPE required but not available");
+	    return;
+	}
+	if (!numbits) {
+	    ppp_error("MPPE required, but MS-CHAP[v2] auth not performed.");
+	    lcp_close(pcb, "MPPE required but not available");
+	    return;
+	}
+
+	/* A plugin (eg radius) may not have obtained key material. */
+	if (!pcb->mppe_keys_set) {
+	    ppp_error("MPPE required, but keys are not available.  "
+		  "Possible plugin problem?");
+	    lcp_close(pcb, "MPPE required but not available");
+	    return;
+	}
+
+	/* LM auth not supported for MPPE */
+	if (pcb->auth_done & (CHAP_MS_WITHPEER | CHAP_MS_PEER)) {
+	    /* This might be noise */
+	    if (go->mppe & MPPE_OPT_40) {
+		ppp_notice("Disabling 40-bit MPPE; MS-CHAP LM not supported");
+		go->mppe &= ~MPPE_OPT_40;
+		wo->mppe &= ~MPPE_OPT_40;
+	    }
+	}
+
+	/* Last check: can we actually negotiate something? */
+	if (!(go->mppe & (MPPE_OPT_40 | MPPE_OPT_128))) {
+	    /* Could be misconfig, could be 40-bit disabled above. */
+	    ppp_error("MPPE required, but both 40-bit and 128-bit disabled.");
+	    lcp_close(pcb, "MPPE required but not available");
+	    return;
+	}
+
+	/* sync options */
+	ao->mppe = go->mppe;
+	/* MPPE is not compatible with other compression types */
+#if BSDCOMPRESS_SUPPORT
+	ao->bsd_compress = go->bsd_compress = 0;
+#endif /* BSDCOMPRESS_SUPPORT */
+#if PREDICTOR_SUPPORT
+	ao->predictor_1  = go->predictor_1  = 0;
+	ao->predictor_2  = go->predictor_2  = 0;
+#endif /* PREDICTOR_SUPPORT */
+#if DEFLATE_SUPPORT
+	ao->deflate      = go->deflate      = 0;
+#endif /* DEFLATE_SUPPORT */
+    }
+#endif /* MPPE_SUPPORT */
+
+    /*
+     * Check whether the kernel knows about the various
+     * compression methods we might request.
+     */
+#if BSDCOMPRESS_SUPPORT
+    /* FIXME: we don't need to test if BSD compress is available
+     * if BSDCOMPRESS_SUPPORT is set, it is.
+     */
+    if (go->bsd_compress) {
+	opt_buf[0] = CI_BSD_COMPRESS;
+	opt_buf[1] = CILEN_BSD_COMPRESS;
+	for (;;) {
+	    if (go->bsd_bits < BSD_MIN_BITS) {
+		go->bsd_compress = 0;
+		break;
+	    }
+	    opt_buf[2] = BSD_MAKE_OPT(BSD_CURRENT_VERSION, go->bsd_bits);
+	    res = ccp_test(pcb, opt_buf, CILEN_BSD_COMPRESS, 0);
+	    if (res > 0) {
+		break;
+	    } else if (res < 0) {
+		go->bsd_compress = 0;
+		break;
+	    }
+	    go->bsd_bits--;
+	}
+    }
+#endif /* BSDCOMPRESS_SUPPORT */
+#if DEFLATE_SUPPORT
+    /* FIXME: we don't need to test if deflate is available
+     * if DEFLATE_SUPPORT is set, it is.
+     */
+    if (go->deflate) {
+	if (go->deflate_correct) {
+	    opt_buf[0] = CI_DEFLATE;
+	    opt_buf[1] = CILEN_DEFLATE;
+	    opt_buf[3] = DEFLATE_CHK_SEQUENCE;
+	    for (;;) {
+		if (go->deflate_size < DEFLATE_MIN_WORKS) {
+		    go->deflate_correct = 0;
+		    break;
+		}
+		opt_buf[2] = DEFLATE_MAKE_OPT(go->deflate_size);
+		res = ccp_test(pcb, opt_buf, CILEN_DEFLATE, 0);
+		if (res > 0) {
+		    break;
+		} else if (res < 0) {
+		    go->deflate_correct = 0;
+		    break;
+		}
+		go->deflate_size--;
+	    }
+	}
+	if (go->deflate_draft) {
+	    opt_buf[0] = CI_DEFLATE_DRAFT;
+	    opt_buf[1] = CILEN_DEFLATE;
+	    opt_buf[3] = DEFLATE_CHK_SEQUENCE;
+	    for (;;) {
+		if (go->deflate_size < DEFLATE_MIN_WORKS) {
+		    go->deflate_draft = 0;
+		    break;
+		}
+		opt_buf[2] = DEFLATE_MAKE_OPT(go->deflate_size);
+		res = ccp_test(pcb, opt_buf, CILEN_DEFLATE, 0);
+		if (res > 0) {
+		    break;
+		} else if (res < 0) {
+		    go->deflate_draft = 0;
+		    break;
+		}
+		go->deflate_size--;
+	    }
+	}
+	if (!go->deflate_correct && !go->deflate_draft)
+	    go->deflate = 0;
+    }
+#endif /* DEFLATE_SUPPORT */
+#if PREDICTOR_SUPPORT
+    /* FIXME: we don't need to test if predictor is available,
+     * if PREDICTOR_SUPPORT is set, it is.
+     */
+    if (go->predictor_1) {
+	opt_buf[0] = CI_PREDICTOR_1;
+	opt_buf[1] = CILEN_PREDICTOR_1;
+	if (ccp_test(pcb, opt_buf, CILEN_PREDICTOR_1, 0) <= 0)
+	    go->predictor_1 = 0;
+    }
+    if (go->predictor_2) {
+	opt_buf[0] = CI_PREDICTOR_2;
+	opt_buf[1] = CILEN_PREDICTOR_2;
+	if (ccp_test(pcb, opt_buf, CILEN_PREDICTOR_2, 0) <= 0)
+	    go->predictor_2 = 0;
+    }
+#endif /* PREDICTOR_SUPPORT */
+}
+
+/*
+ * ccp_cilen - Return total length of our configuration info.
+ */
+static int ccp_cilen(fsm *f) {
+    ppp_pcb *pcb = f->pcb;
+    ccp_options *go = &pcb->ccp_gotoptions;
+
+    return 0
+#if BSDCOMPRESS_SUPPORT
+	+ (go->bsd_compress? CILEN_BSD_COMPRESS: 0)
+#endif /* BSDCOMPRESS_SUPPORT */
+#if DEFLATE_SUPPORT
+	+ (go->deflate && go->deflate_correct? CILEN_DEFLATE: 0)
+	+ (go->deflate && go->deflate_draft? CILEN_DEFLATE: 0)
+#endif /* DEFLATE_SUPPORT */
+#if PREDICTOR_SUPPORT
+	+ (go->predictor_1? CILEN_PREDICTOR_1: 0)
+	+ (go->predictor_2? CILEN_PREDICTOR_2: 0)
+#endif /* PREDICTOR_SUPPORT */
+#if MPPE_SUPPORT
+	+ (go->mppe? CILEN_MPPE: 0)
+#endif /* MPPE_SUPPORT */
+	;
+}
+
+/*
+ * ccp_addci - put our requests in a packet.
+ */
+static void ccp_addci(fsm *f, u_char *p, int *lenp) {
+    ppp_pcb *pcb = f->pcb;
+    ccp_options *go = &pcb->ccp_gotoptions;
+    u_char *p0 = p;
+
+    /*
+     * Add the compression types that we can receive, in decreasing
+     * preference order.
+     */
+#if MPPE_SUPPORT
+    if (go->mppe) {
+	p[0] = CI_MPPE;
+	p[1] = CILEN_MPPE;
+	MPPE_OPTS_TO_CI(go->mppe, &p[2]);
+	mppe_init(pcb, &pcb->mppe_decomp, go->mppe);
+	p += CILEN_MPPE;
+    }
+#endif /* MPPE_SUPPORT */
+#if DEFLATE_SUPPORT
+    if (go->deflate) {
+	if (go->deflate_correct) {
+	    p[0] = CI_DEFLATE;
+	    p[1] = CILEN_DEFLATE;
+	    p[2] = DEFLATE_MAKE_OPT(go->deflate_size);
+	    p[3] = DEFLATE_CHK_SEQUENCE;
+	    p += CILEN_DEFLATE;
+	}
+	if (go->deflate_draft) {
+	    p[0] = CI_DEFLATE_DRAFT;
+	    p[1] = CILEN_DEFLATE;
+	    p[2] = p[2 - CILEN_DEFLATE];
+	    p[3] = DEFLATE_CHK_SEQUENCE;
+	    p += CILEN_DEFLATE;
+	}
+    }
+#endif /* DEFLATE_SUPPORT */
+#if BSDCOMPRESS_SUPPORT
+    if (go->bsd_compress) {
+	p[0] = CI_BSD_COMPRESS;
+	p[1] = CILEN_BSD_COMPRESS;
+	p[2] = BSD_MAKE_OPT(BSD_CURRENT_VERSION, go->bsd_bits);
+	p += CILEN_BSD_COMPRESS;
+    }
+#endif /* BSDCOMPRESS_SUPPORT */
+#if PREDICTOR_SUPPORT
+    /* XXX Should Predictor 2 be preferable to Predictor 1? */
+    if (go->predictor_1) {
+	p[0] = CI_PREDICTOR_1;
+	p[1] = CILEN_PREDICTOR_1;
+	p += CILEN_PREDICTOR_1;
+    }
+    if (go->predictor_2) {
+	p[0] = CI_PREDICTOR_2;
+	p[1] = CILEN_PREDICTOR_2;
+	p += CILEN_PREDICTOR_2;
+    }
+#endif /* PREDICTOR_SUPPORT */
+
+    go->method = (p > p0)? p0[0]: 0;
+
+    *lenp = p - p0;
+}
+
+/*
+ * ccp_ackci - process a received configure-ack, and return
+ * 1 iff the packet was OK.
+ */
+static int ccp_ackci(fsm *f, u_char *p, int len) {
+    ppp_pcb *pcb = f->pcb;
+    ccp_options *go = &pcb->ccp_gotoptions;
+#if BSDCOMPRESS_SUPPORT || PREDICTOR_SUPPORT
+    u_char *p0 = p;
+#endif /* BSDCOMPRESS_SUPPORT || PREDICTOR_SUPPORT */
+
+#if MPPE_SUPPORT
+    if (go->mppe) {
+	u_char opt_buf[CILEN_MPPE];
+
+	opt_buf[0] = CI_MPPE;
+	opt_buf[1] = CILEN_MPPE;
+	MPPE_OPTS_TO_CI(go->mppe, &opt_buf[2]);
+	if (len < CILEN_MPPE || memcmp(opt_buf, p, CILEN_MPPE))
+	    return 0;
+	p += CILEN_MPPE;
+	len -= CILEN_MPPE;
+	/* XXX Cope with first/fast ack */
+	if (len == 0)
+	    return 1;
+    }
+#endif /* MPPE_SUPPORT */
+#if DEFLATE_SUPPORT
+    if (go->deflate) {
+	if (len < CILEN_DEFLATE
+	    || p[0] != (go->deflate_correct? CI_DEFLATE: CI_DEFLATE_DRAFT)
+	    || p[1] != CILEN_DEFLATE
+	    || p[2] != DEFLATE_MAKE_OPT(go->deflate_size)
+	    || p[3] != DEFLATE_CHK_SEQUENCE)
+	    return 0;
+	p += CILEN_DEFLATE;
+	len -= CILEN_DEFLATE;
+	/* XXX Cope with first/fast ack */
+	if (len == 0)
+	    return 1;
+	if (go->deflate_correct && go->deflate_draft) {
+	    if (len < CILEN_DEFLATE
+		|| p[0] != CI_DEFLATE_DRAFT
+		|| p[1] != CILEN_DEFLATE
+		|| p[2] != DEFLATE_MAKE_OPT(go->deflate_size)
+		|| p[3] != DEFLATE_CHK_SEQUENCE)
+		return 0;
+	    p += CILEN_DEFLATE;
+	    len -= CILEN_DEFLATE;
+	}
+    }
+#endif /* DEFLATE_SUPPORT */
+#if BSDCOMPRESS_SUPPORT
+    if (go->bsd_compress) {
+	if (len < CILEN_BSD_COMPRESS
+	    || p[0] != CI_BSD_COMPRESS || p[1] != CILEN_BSD_COMPRESS
+	    || p[2] != BSD_MAKE_OPT(BSD_CURRENT_VERSION, go->bsd_bits))
+	    return 0;
+	p += CILEN_BSD_COMPRESS;
+	len -= CILEN_BSD_COMPRESS;
+	/* XXX Cope with first/fast ack */
+	if (p == p0 && len == 0)
+	    return 1;
+    }
+#endif /* BSDCOMPRESS_SUPPORT */
+#if PREDICTOR_SUPPORT
+    if (go->predictor_1) {
+	if (len < CILEN_PREDICTOR_1
+	    || p[0] != CI_PREDICTOR_1 || p[1] != CILEN_PREDICTOR_1)
+	    return 0;
+	p += CILEN_PREDICTOR_1;
+	len -= CILEN_PREDICTOR_1;
+	/* XXX Cope with first/fast ack */
+	if (p == p0 && len == 0)
+	    return 1;
+    }
+    if (go->predictor_2) {
+	if (len < CILEN_PREDICTOR_2
+	    || p[0] != CI_PREDICTOR_2 || p[1] != CILEN_PREDICTOR_2)
+	    return 0;
+	p += CILEN_PREDICTOR_2;
+	len -= CILEN_PREDICTOR_2;
+	/* XXX Cope with first/fast ack */
+	if (p == p0 && len == 0)
+	    return 1;
+    }
+#endif /* PREDICTOR_SUPPORT */
+
+    if (len != 0)
+	return 0;
+    return 1;
+}
+
+/*
+ * ccp_nakci - process received configure-nak.
+ * Returns 1 iff the nak was OK.
+ */
+static int ccp_nakci(fsm *f, u_char *p, int len, int treat_as_reject) {
+    ppp_pcb *pcb = f->pcb;
+    ccp_options *go = &pcb->ccp_gotoptions;
+    ccp_options no;		/* options we've seen already */
+    ccp_options try_;		/* options to ask for next time */
+    LWIP_UNUSED_ARG(treat_as_reject);
+#if !MPPE_SUPPORT && !DEFLATE_SUPPORT && !BSDCOMPRESS_SUPPORT
+    LWIP_UNUSED_ARG(p);
+    LWIP_UNUSED_ARG(len);
+#endif /* !MPPE_SUPPORT && !DEFLATE_SUPPORT && !BSDCOMPRESS_SUPPORT */
+
+    memset(&no, 0, sizeof(no));
+    try_ = *go;
+
+#if MPPE_SUPPORT
+    if (go->mppe && len >= CILEN_MPPE
+	&& p[0] == CI_MPPE && p[1] == CILEN_MPPE) {
+	no.mppe = 1;
+	/*
+	 * Peer wants us to use a different strength or other setting.
+	 * Fail if we aren't willing to use his suggestion.
+	 */
+	MPPE_CI_TO_OPTS(&p[2], try_.mppe);
+	if ((try_.mppe & MPPE_OPT_STATEFUL) && pcb->settings.refuse_mppe_stateful) {
+	    ppp_error("Refusing MPPE stateful mode offered by peer");
+	    try_.mppe = 0;
+	} else if (((go->mppe | MPPE_OPT_STATEFUL) & try_.mppe) != try_.mppe) {
+	    /* Peer must have set options we didn't request (suggest) */
+	    try_.mppe = 0;
+	}
+
+	if (!try_.mppe) {
+	    ppp_error("MPPE required but peer negotiation failed");
+	    lcp_close(pcb, "MPPE required but peer negotiation failed");
+	}
+    }
+#endif /* MPPE_SUPPORT */
+#if DEFLATE_SUPPORT
+    if (go->deflate && len >= CILEN_DEFLATE
+	&& p[0] == (go->deflate_correct? CI_DEFLATE: CI_DEFLATE_DRAFT)
+	&& p[1] == CILEN_DEFLATE) {
+	no.deflate = 1;
+	/*
+	 * Peer wants us to use a different code size or something.
+	 * Stop asking for Deflate if we don't understand his suggestion.
+	 */
+	if (DEFLATE_METHOD(p[2]) != DEFLATE_METHOD_VAL
+	    || DEFLATE_SIZE(p[2]) < DEFLATE_MIN_WORKS
+	    || p[3] != DEFLATE_CHK_SEQUENCE)
+	    try_.deflate = 0;
+	else if (DEFLATE_SIZE(p[2]) < go->deflate_size)
+	    try_.deflate_size = DEFLATE_SIZE(p[2]);
+	p += CILEN_DEFLATE;
+	len -= CILEN_DEFLATE;
+	if (go->deflate_correct && go->deflate_draft
+	    && len >= CILEN_DEFLATE && p[0] == CI_DEFLATE_DRAFT
+	    && p[1] == CILEN_DEFLATE) {
+	    p += CILEN_DEFLATE;
+	    len -= CILEN_DEFLATE;
+	}
+    }
+#endif /* DEFLATE_SUPPORT */
+#if BSDCOMPRESS_SUPPORT
+    if (go->bsd_compress && len >= CILEN_BSD_COMPRESS
+	&& p[0] == CI_BSD_COMPRESS && p[1] == CILEN_BSD_COMPRESS) {
+	no.bsd_compress = 1;
+	/*
+	 * Peer wants us to use a different number of bits
+	 * or a different version.
+	 */
+	if (BSD_VERSION(p[2]) != BSD_CURRENT_VERSION)
+	    try_.bsd_compress = 0;
+	else if (BSD_NBITS(p[2]) < go->bsd_bits)
+	    try_.bsd_bits = BSD_NBITS(p[2]);
+	p += CILEN_BSD_COMPRESS;
+	len -= CILEN_BSD_COMPRESS;
+    }
+#endif /* BSDCOMPRESS_SUPPORT */
+
+    /*
+     * Predictor-1 and 2 have no options, so they can't be Naked.
+     *
+     * There may be remaining options but we ignore them.
+     */
+
+    if (f->state != PPP_FSM_OPENED)
+	*go = try_;
+    return 1;
+}
+
+/*
+ * ccp_rejci - reject some of our suggested compression methods.
+ */
+static int ccp_rejci(fsm *f, u_char *p, int len) {
+    ppp_pcb *pcb = f->pcb;
+    ccp_options *go = &pcb->ccp_gotoptions;
+    ccp_options try_;		/* options to request next time */
+
+    try_ = *go;
+
+    /*
+     * Cope with empty configure-rejects by ceasing to send
+     * configure-requests.
+     */
+    if (len == 0 && pcb->ccp_all_rejected)
+	return -1;
+
+#if MPPE_SUPPORT
+    if (go->mppe && len >= CILEN_MPPE
+	&& p[0] == CI_MPPE && p[1] == CILEN_MPPE) {
+	ppp_error("MPPE required but peer refused");
+	lcp_close(pcb, "MPPE required but peer refused");
+	p += CILEN_MPPE;
+	len -= CILEN_MPPE;
+    }
+#endif /* MPPE_SUPPORT */
+#if DEFLATE_SUPPORT
+    if (go->deflate_correct && len >= CILEN_DEFLATE
+	&& p[0] == CI_DEFLATE && p[1] == CILEN_DEFLATE) {
+	if (p[2] != DEFLATE_MAKE_OPT(go->deflate_size)
+	    || p[3] != DEFLATE_CHK_SEQUENCE)
+	    return 0;		/* Rej is bad */
+	try_.deflate_correct = 0;
+	p += CILEN_DEFLATE;
+	len -= CILEN_DEFLATE;
+    }
+    if (go->deflate_draft && len >= CILEN_DEFLATE
+	&& p[0] == CI_DEFLATE_DRAFT && p[1] == CILEN_DEFLATE) {
+	if (p[2] != DEFLATE_MAKE_OPT(go->deflate_size)
+	    || p[3] != DEFLATE_CHK_SEQUENCE)
+	    return 0;		/* Rej is bad */
+	try_.deflate_draft = 0;
+	p += CILEN_DEFLATE;
+	len -= CILEN_DEFLATE;
+    }
+    if (!try_.deflate_correct && !try_.deflate_draft)
+	try_.deflate = 0;
+#endif /* DEFLATE_SUPPORT */
+#if BSDCOMPRESS_SUPPORT
+    if (go->bsd_compress && len >= CILEN_BSD_COMPRESS
+	&& p[0] == CI_BSD_COMPRESS && p[1] == CILEN_BSD_COMPRESS) {
+	if (p[2] != BSD_MAKE_OPT(BSD_CURRENT_VERSION, go->bsd_bits))
+	    return 0;
+	try_.bsd_compress = 0;
+	p += CILEN_BSD_COMPRESS;
+	len -= CILEN_BSD_COMPRESS;
+    }
+#endif /* BSDCOMPRESS_SUPPORT */
+#if PREDICTOR_SUPPORT
+    if (go->predictor_1 && len >= CILEN_PREDICTOR_1
+	&& p[0] == CI_PREDICTOR_1 && p[1] == CILEN_PREDICTOR_1) {
+	try_.predictor_1 = 0;
+	p += CILEN_PREDICTOR_1;
+	len -= CILEN_PREDICTOR_1;
+    }
+    if (go->predictor_2 && len >= CILEN_PREDICTOR_2
+	&& p[0] == CI_PREDICTOR_2 && p[1] == CILEN_PREDICTOR_2) {
+	try_.predictor_2 = 0;
+	p += CILEN_PREDICTOR_2;
+	len -= CILEN_PREDICTOR_2;
+    }
+#endif /* PREDICTOR_SUPPORT */
+
+    if (len != 0)
+	return 0;
+
+    if (f->state != PPP_FSM_OPENED)
+	*go = try_;
+
+    return 1;
+}
+
+/*
+ * ccp_reqci - processed a received configure-request.
+ * Returns CONFACK, CONFNAK or CONFREJ and the packet modified
+ * appropriately.
+ */
+static int ccp_reqci(fsm *f, u_char *p, int *lenp, int dont_nak) {
+    ppp_pcb *pcb = f->pcb;
+    ccp_options *ho = &pcb->ccp_hisoptions;
+    ccp_options *ao = &pcb->ccp_allowoptions;
+    int ret, newret;
+#if DEFLATE_SUPPORT || BSDCOMPRESS_SUPPORT
+    int res;
+    int nb;
+#endif /* DEFLATE_SUPPORT || BSDCOMPRESS_SUPPORT */
+    u_char *p0, *retp;
+    int len, clen, type;
+#if MPPE_SUPPORT
+    u8_t rej_for_ci_mppe = 1;	/* Are we rejecting based on a bad/missing */
+				/* CI_MPPE, or due to other options?       */
+#endif /* MPPE_SUPPORT */
+
+    ret = CONFACK;
+    retp = p0 = p;
+    len = *lenp;
+
+    memset(ho, 0, sizeof(ccp_options));
+    ho->method = (len > 0)? p[0]: 0;
+
+    while (len > 0) {
+	newret = CONFACK;
+	if (len < 2 || p[1] < 2 || p[1] > len) {
+	    /* length is bad */
+	    clen = len;
+	    newret = CONFREJ;
+
+	} else {
+	    type = p[0];
+	    clen = p[1];
+
+	    switch (type) {
+#if MPPE_SUPPORT
+	    case CI_MPPE:
+		if (!ao->mppe || clen != CILEN_MPPE) {
+		    newret = CONFREJ;
+		    break;
+		}
+		MPPE_CI_TO_OPTS(&p[2], ho->mppe);
+
+		/* Nak if anything unsupported or unknown are set. */
+		if (ho->mppe & MPPE_OPT_UNSUPPORTED) {
+		    newret = CONFNAK;
+		    ho->mppe &= ~MPPE_OPT_UNSUPPORTED;
+		}
+		if (ho->mppe & MPPE_OPT_UNKNOWN) {
+		    newret = CONFNAK;
+		    ho->mppe &= ~MPPE_OPT_UNKNOWN;
+		}
+
+		/* Check state opt */
+		if (ho->mppe & MPPE_OPT_STATEFUL) {
+		    /*
+		     * We can Nak and request stateless, but it's a
+		     * lot easier to just assume the peer will request
+		     * it if he can do it; stateful mode is bad over
+		     * the Internet -- which is where we expect MPPE.
+		     */
+		   if (pcb->settings.refuse_mppe_stateful) {
+			ppp_error("Refusing MPPE stateful mode offered by peer");
+			newret = CONFREJ;
+			break;
+		    }
+		}
+
+		/* Find out which of {S,L} are set. */
+		if ((ho->mppe & MPPE_OPT_128)
+		     && (ho->mppe & MPPE_OPT_40)) {
+		    /* Both are set, negotiate the strongest. */
+		    newret = CONFNAK;
+		    if (ao->mppe & MPPE_OPT_128)
+			ho->mppe &= ~MPPE_OPT_40;
+		    else if (ao->mppe & MPPE_OPT_40)
+			ho->mppe &= ~MPPE_OPT_128;
+		    else {
+			newret = CONFREJ;
+			break;
+		    }
+		} else if (ho->mppe & MPPE_OPT_128) {
+		    if (!(ao->mppe & MPPE_OPT_128)) {
+			newret = CONFREJ;
+			break;
+		    }
+		} else if (ho->mppe & MPPE_OPT_40) {
+		    if (!(ao->mppe & MPPE_OPT_40)) {
+			newret = CONFREJ;
+			break;
+		    }
+		} else {
+		    /* Neither are set. */
+		    /* We cannot accept this.  */
+		    newret = CONFNAK;
+		    /* Give the peer our idea of what can be used,
+		       so it can choose and confirm */
+		    ho->mppe = ao->mppe;
+		}
+
+		/* rebuild the opts */
+		MPPE_OPTS_TO_CI(ho->mppe, &p[2]);
+		if (newret == CONFACK) {
+		    int mtu;
+
+		    mppe_init(pcb, &pcb->mppe_comp, ho->mppe);
+		    /*
+		     * We need to decrease the interface MTU by MPPE_PAD
+		     * because MPPE frames **grow**.  The kernel [must]
+		     * allocate MPPE_PAD extra bytes in xmit buffers.
+		     */
+		    mtu = netif_get_mtu(pcb);
+		    if (mtu)
+			netif_set_mtu(pcb, mtu - MPPE_PAD);
+		    else
+			newret = CONFREJ;
+		}
+
+		/*
+		 * We have accepted MPPE or are willing to negotiate
+		 * MPPE parameters.  A CONFREJ is due to subsequent
+		 * (non-MPPE) processing.
+		 */
+		rej_for_ci_mppe = 0;
+		break;
+#endif /* MPPE_SUPPORT */
+#if DEFLATE_SUPPORT
+	    case CI_DEFLATE:
+	    case CI_DEFLATE_DRAFT:
+		if (!ao->deflate || clen != CILEN_DEFLATE
+		    || (!ao->deflate_correct && type == CI_DEFLATE)
+		    || (!ao->deflate_draft && type == CI_DEFLATE_DRAFT)) {
+		    newret = CONFREJ;
+		    break;
+		}
+
+		ho->deflate = 1;
+		ho->deflate_size = nb = DEFLATE_SIZE(p[2]);
+		if (DEFLATE_METHOD(p[2]) != DEFLATE_METHOD_VAL
+		    || p[3] != DEFLATE_CHK_SEQUENCE
+		    || nb > ao->deflate_size || nb < DEFLATE_MIN_WORKS) {
+		    newret = CONFNAK;
+		    if (!dont_nak) {
+			p[2] = DEFLATE_MAKE_OPT(ao->deflate_size);
+			p[3] = DEFLATE_CHK_SEQUENCE;
+			/* fall through to test this #bits below */
+		    } else
+			break;
+		}
+
+		/*
+		 * Check whether we can do Deflate with the window
+		 * size they want.  If the window is too big, reduce
+		 * it until the kernel can cope and nak with that.
+		 * We only check this for the first option.
+		 */
+		if (p == p0) {
+		    for (;;) {
+			res = ccp_test(pcb, p, CILEN_DEFLATE, 1);
+			if (res > 0)
+			    break;		/* it's OK now */
+			if (res < 0 || nb == DEFLATE_MIN_WORKS || dont_nak) {
+			    newret = CONFREJ;
+			    p[2] = DEFLATE_MAKE_OPT(ho->deflate_size);
+			    break;
+			}
+			newret = CONFNAK;
+			--nb;
+			p[2] = DEFLATE_MAKE_OPT(nb);
+		    }
+		}
+		break;
+#endif /* DEFLATE_SUPPORT */
+#if BSDCOMPRESS_SUPPORT
+	    case CI_BSD_COMPRESS:
+		if (!ao->bsd_compress || clen != CILEN_BSD_COMPRESS) {
+		    newret = CONFREJ;
+		    break;
+		}
+
+		ho->bsd_compress = 1;
+		ho->bsd_bits = nb = BSD_NBITS(p[2]);
+		if (BSD_VERSION(p[2]) != BSD_CURRENT_VERSION
+		    || nb > ao->bsd_bits || nb < BSD_MIN_BITS) {
+		    newret = CONFNAK;
+		    if (!dont_nak) {
+			p[2] = BSD_MAKE_OPT(BSD_CURRENT_VERSION, ao->bsd_bits);
+			/* fall through to test this #bits below */
+		    } else
+			break;
+		}
+
+		/*
+		 * Check whether we can do BSD-Compress with the code
+		 * size they want.  If the code size is too big, reduce
+		 * it until the kernel can cope and nak with that.
+		 * We only check this for the first option.
+		 */
+		if (p == p0) {
+		    for (;;) {
+			res = ccp_test(pcb, p, CILEN_BSD_COMPRESS, 1);
+			if (res > 0)
+			    break;
+			if (res < 0 || nb == BSD_MIN_BITS || dont_nak) {
+			    newret = CONFREJ;
+			    p[2] = BSD_MAKE_OPT(BSD_CURRENT_VERSION,
+						ho->bsd_bits);
+			    break;
+			}
+			newret = CONFNAK;
+			--nb;
+			p[2] = BSD_MAKE_OPT(BSD_CURRENT_VERSION, nb);
+		    }
+		}
+		break;
+#endif /* BSDCOMPRESS_SUPPORT */
+#if PREDICTOR_SUPPORT
+	    case CI_PREDICTOR_1:
+		if (!ao->predictor_1 || clen != CILEN_PREDICTOR_1) {
+		    newret = CONFREJ;
+		    break;
+		}
+
+		ho->predictor_1 = 1;
+		if (p == p0
+		    && ccp_test(pcb, p, CILEN_PREDICTOR_1, 1) <= 0) {
+		    newret = CONFREJ;
+		}
+		break;
+
+	    case CI_PREDICTOR_2:
+		if (!ao->predictor_2 || clen != CILEN_PREDICTOR_2) {
+		    newret = CONFREJ;
+		    break;
+		}
+
+		ho->predictor_2 = 1;
+		if (p == p0
+		    && ccp_test(pcb, p, CILEN_PREDICTOR_2, 1) <= 0) {
+		    newret = CONFREJ;
+		}
+		break;
+#endif /* PREDICTOR_SUPPORT */
+
+	    default:
+		newret = CONFREJ;
+	    }
+	}
+
+	if (newret == CONFNAK && dont_nak)
+	    newret = CONFREJ;
+	if (!(newret == CONFACK || (newret == CONFNAK && ret == CONFREJ))) {
+	    /* we're returning this option */
+	    if (newret == CONFREJ && ret == CONFNAK)
+		retp = p0;
+	    ret = newret;
+	    if (p != retp)
+		MEMCPY(retp, p, clen);
+	    retp += clen;
+	}
+
+	p += clen;
+	len -= clen;
+    }
+
+    if (ret != CONFACK) {
+	if (ret == CONFREJ && *lenp == retp - p0)
+	    pcb->ccp_all_rejected = 1;
+	else
+	    *lenp = retp - p0;
+    }
+#if MPPE_SUPPORT
+    if (ret == CONFREJ && ao->mppe && rej_for_ci_mppe) {
+	ppp_error("MPPE required but peer negotiation failed");
+	lcp_close(pcb, "MPPE required but peer negotiation failed");
+    }
+#endif /* MPPE_SUPPORT */
+    return ret;
+}
+
+/*
+ * Make a string name for a compression method (or 2).
+ */
+static const char *method_name(ccp_options *opt, ccp_options *opt2) {
+    static char result[64];
+#if !DEFLATE_SUPPORT && !BSDCOMPRESS_SUPPORT
+    LWIP_UNUSED_ARG(opt2);
+#endif /* !DEFLATE_SUPPORT && !BSDCOMPRESS_SUPPORT */
+
+    if (!ccp_anycompress(opt))
+	return "(none)";
+    switch (opt->method) {
+#if MPPE_SUPPORT
+    case CI_MPPE:
+    {
+	char *p = result;
+	char *q = result + sizeof(result); /* 1 past result */
+
+	ppp_slprintf(p, q - p, "MPPE ");
+	p += 5;
+	if (opt->mppe & MPPE_OPT_128) {
+	    ppp_slprintf(p, q - p, "128-bit ");
+	    p += 8;
+	}
+	if (opt->mppe & MPPE_OPT_40) {
+	    ppp_slprintf(p, q - p, "40-bit ");
+	    p += 7;
+	}
+	if (opt->mppe & MPPE_OPT_STATEFUL)
+	    ppp_slprintf(p, q - p, "stateful");
+	else
+	    ppp_slprintf(p, q - p, "stateless");
+
+	break;
+    }
+#endif /* MPPE_SUPPORT */
+#if DEFLATE_SUPPORT
+    case CI_DEFLATE:
+    case CI_DEFLATE_DRAFT:
+	if (opt2 != NULL && opt2->deflate_size != opt->deflate_size)
+	    ppp_slprintf(result, sizeof(result), "Deflate%s (%d/%d)",
+		     (opt->method == CI_DEFLATE_DRAFT? "(old#)": ""),
+		     opt->deflate_size, opt2->deflate_size);
+	else
+	    ppp_slprintf(result, sizeof(result), "Deflate%s (%d)",
+		     (opt->method == CI_DEFLATE_DRAFT? "(old#)": ""),
+		     opt->deflate_size);
+	break;
+#endif /* DEFLATE_SUPPORT */
+#if BSDCOMPRESS_SUPPORT
+    case CI_BSD_COMPRESS:
+	if (opt2 != NULL && opt2->bsd_bits != opt->bsd_bits)
+	    ppp_slprintf(result, sizeof(result), "BSD-Compress (%d/%d)",
+		     opt->bsd_bits, opt2->bsd_bits);
+	else
+	    ppp_slprintf(result, sizeof(result), "BSD-Compress (%d)",
+		     opt->bsd_bits);
+	break;
+#endif /* BSDCOMPRESS_SUPPORT */
+#if PREDICTOR_SUPPORT
+    case CI_PREDICTOR_1:
+	return "Predictor 1";
+    case CI_PREDICTOR_2:
+	return "Predictor 2";
+#endif /* PREDICTOR_SUPPORT */
+    default:
+	ppp_slprintf(result, sizeof(result), "Method %d", opt->method);
+    }
+    return result;
+}
+
+/*
+ * CCP has come up - inform the kernel driver and log a message.
+ */
+static void ccp_up(fsm *f) {
+    ppp_pcb *pcb = f->pcb;
+    ccp_options *go = &pcb->ccp_gotoptions;
+    ccp_options *ho = &pcb->ccp_hisoptions;
+    char method1[64];
+
+    ccp_set(pcb, 1, 1, go->method, ho->method);
+    if (ccp_anycompress(go)) {
+	if (ccp_anycompress(ho)) {
+	    if (go->method == ho->method) {
+		ppp_notice("%s compression enabled", method_name(go, ho));
+	    } else {
+		ppp_strlcpy(method1, method_name(go, NULL), sizeof(method1));
+		ppp_notice("%s / %s compression enabled",
+		       method1, method_name(ho, NULL));
+	    }
+	} else
+	    ppp_notice("%s receive compression enabled", method_name(go, NULL));
+    } else if (ccp_anycompress(ho))
+	ppp_notice("%s transmit compression enabled", method_name(ho, NULL));
+#if MPPE_SUPPORT
+    if (go->mppe) {
+	continue_networks(pcb);		/* Bring up IP et al */
+    }
+#endif /* MPPE_SUPPORT */
+}
+
+/*
+ * CCP has gone down - inform the kernel driver.
+ */
+static void ccp_down(fsm *f) {
+    ppp_pcb *pcb = f->pcb;
+#if MPPE_SUPPORT
+    ccp_options *go = &pcb->ccp_gotoptions;
+#endif /* MPPE_SUPPORT */
+
+    if (pcb->ccp_localstate & RACK_PENDING)
+	UNTIMEOUT(ccp_rack_timeout, f);
+    pcb->ccp_localstate = 0;
+    ccp_set(pcb, 1, 0, 0, 0);
+#if MPPE_SUPPORT
+    if (go->mppe) {
+	go->mppe = 0;
+	if (pcb->lcp_fsm.state == PPP_FSM_OPENED) {
+	    /* If LCP is not already going down, make sure it does. */
+	    ppp_error("MPPE disabled");
+	    lcp_close(pcb, "MPPE disabled");
+	}
+    }
+#endif /* MPPE_SUPPORT */
+}
+
+#if PRINTPKT_SUPPORT
+/*
+ * Print the contents of a CCP packet.
+ */
+static const char* const ccp_codenames[] = {
+    "ConfReq", "ConfAck", "ConfNak", "ConfRej",
+    "TermReq", "TermAck", "CodeRej",
+    NULL, NULL, NULL, NULL, NULL, NULL,
+    "ResetReq", "ResetAck",
+};
+
+static int ccp_printpkt(const u_char *p, int plen, void (*printer) (void *, const char *, ...), void *arg) {
+    const u_char *p0, *optend;
+    int code, id, len;
+    int optlen;
+
+    p0 = p;
+    if (plen < HEADERLEN)
+	return 0;
+    code = p[0];
+    id = p[1];
+    len = (p[2] << 8) + p[3];
+    if (len < HEADERLEN || len > plen)
+	return 0;
+
+    if (code >= 1 && code <= (int)LWIP_ARRAYSIZE(ccp_codenames) && ccp_codenames[code-1] != NULL)
+	printer(arg, " %s", ccp_codenames[code-1]);
+    else
+	printer(arg, " code=0x%x", code);
+    printer(arg, " id=0x%x", id);
+    len -= HEADERLEN;
+    p += HEADERLEN;
+
+    switch (code) {
+    case CONFREQ:
+    case CONFACK:
+    case CONFNAK:
+    case CONFREJ:
+	/* print list of possible compression methods */
+	while (len >= 2) {
+	    code = p[0];
+	    optlen = p[1];
+	    if (optlen < 2 || optlen > len)
+		break;
+	    printer(arg, " <");
+	    len -= optlen;
+	    optend = p + optlen;
+	    switch (code) {
+#if MPPE_SUPPORT
+	    case CI_MPPE:
+		if (optlen >= CILEN_MPPE) {
+		    u_char mppe_opts;
+
+		    MPPE_CI_TO_OPTS(&p[2], mppe_opts);
+		    printer(arg, "mppe %s %s %s %s %s %s%s",
+			    (p[2] & MPPE_H_BIT)? "+H": "-H",
+			    (p[5] & MPPE_M_BIT)? "+M": "-M",
+			    (p[5] & MPPE_S_BIT)? "+S": "-S",
+			    (p[5] & MPPE_L_BIT)? "+L": "-L",
+			    (p[5] & MPPE_D_BIT)? "+D": "-D",
+			    (p[5] & MPPE_C_BIT)? "+C": "-C",
+			    (mppe_opts & MPPE_OPT_UNKNOWN)? " +U": "");
+		    if (mppe_opts & MPPE_OPT_UNKNOWN)
+			printer(arg, " (%.2x %.2x %.2x %.2x)",
+				p[2], p[3], p[4], p[5]);
+		    p += CILEN_MPPE;
+		}
+		break;
+#endif /* MPPE_SUPPORT */
+#if DEFLATE_SUPPORT
+	    case CI_DEFLATE:
+	    case CI_DEFLATE_DRAFT:
+		if (optlen >= CILEN_DEFLATE) {
+		    printer(arg, "deflate%s %d",
+			    (code == CI_DEFLATE_DRAFT? "(old#)": ""),
+			    DEFLATE_SIZE(p[2]));
+		    if (DEFLATE_METHOD(p[2]) != DEFLATE_METHOD_VAL)
+			printer(arg, " method %d", DEFLATE_METHOD(p[2]));
+		    if (p[3] != DEFLATE_CHK_SEQUENCE)
+			printer(arg, " check %d", p[3]);
+		    p += CILEN_DEFLATE;
+		}
+		break;
+#endif /* DEFLATE_SUPPORT */
+#if BSDCOMPRESS_SUPPORT
+	    case CI_BSD_COMPRESS:
+		if (optlen >= CILEN_BSD_COMPRESS) {
+		    printer(arg, "bsd v%d %d", BSD_VERSION(p[2]),
+			    BSD_NBITS(p[2]));
+		    p += CILEN_BSD_COMPRESS;
+		}
+		break;
+#endif /* BSDCOMPRESS_SUPPORT */
+#if PREDICTOR_SUPPORT
+	    case CI_PREDICTOR_1:
+		if (optlen >= CILEN_PREDICTOR_1) {
+		    printer(arg, "predictor 1");
+		    p += CILEN_PREDICTOR_1;
+		}
+		break;
+	    case CI_PREDICTOR_2:
+		if (optlen >= CILEN_PREDICTOR_2) {
+		    printer(arg, "predictor 2");
+		    p += CILEN_PREDICTOR_2;
+		}
+		break;
+#endif /* PREDICTOR_SUPPORT */
+	    default:
+                break;
+	    }
+	    while (p < optend)
+		printer(arg, " %.2x", *p++);
+	    printer(arg, ">");
+	}
+	break;
+
+    case TERMACK:
+    case TERMREQ:
+	if (len > 0 && *p >= ' ' && *p < 0x7f) {
+	    ppp_print_string(p, len, printer, arg);
+	    p += len;
+	    len = 0;
+	}
+	break;
+    default:
+        break;
+    }
+
+    /* dump out the rest of the packet in hex */
+    while (--len >= 0)
+	printer(arg, " %.2x", *p++);
+
+    return p - p0;
+}
+#endif /* PRINTPKT_SUPPORT */
+
+#if PPP_DATAINPUT
+/*
+ * We have received a packet that the decompressor failed to
+ * decompress.  Here we would expect to issue a reset-request, but
+ * Motorola has a patent on resetting the compressor as a result of
+ * detecting an error in the decompressed data after decompression.
+ * (See US patent 5,130,993; international patent publication number
+ * WO 91/10289; Australian patent 73296/91.)
+ *
+ * So we ask the kernel whether the error was detected after
+ * decompression; if it was, we take CCP down, thus disabling
+ * compression :-(, otherwise we issue the reset-request.
+ */
+static void ccp_datainput(ppp_pcb *pcb, u_char *pkt, int len) {
+    fsm *f;
+#if MPPE_SUPPORT
+    ccp_options *go = &pcb->ccp_gotoptions;
+#endif /* MPPE_SUPPORT */
+    LWIP_UNUSED_ARG(pkt);
+    LWIP_UNUSED_ARG(len);
+
+    f = &pcb->ccp_fsm;
+    if (f->state == PPP_FSM_OPENED) {
+	if (ccp_fatal_error(pcb)) {
+	    /*
+	     * Disable compression by taking CCP down.
+	     */
+	    ppp_error("Lost compression sync: disabling compression");
+	    ccp_close(pcb, "Lost compression sync");
+#if MPPE_SUPPORT
+	    /*
+	     * If we were doing MPPE, we must also take the link down.
+	     */
+	    if (go->mppe) {
+		ppp_error("Too many MPPE errors, closing LCP");
+		lcp_close(pcb, "Too many MPPE errors");
+	    }
+#endif /* MPPE_SUPPORT */
+	} else {
+	    /*
+	     * Send a reset-request to reset the peer's compressor.
+	     * We don't do that if we are still waiting for an
+	     * acknowledgement to a previous reset-request.
+	     */
+	    if (!(pcb->ccp_localstate & RACK_PENDING)) {
+		fsm_sdata(f, CCP_RESETREQ, f->reqid = ++f->id, NULL, 0);
+		TIMEOUT(ccp_rack_timeout, f, RACKTIMEOUT);
+		pcb->ccp_localstate |= RACK_PENDING;
+	    } else
+		pcb->ccp_localstate |= RREQ_REPEAT;
+	}
+    }
+}
+#endif /* PPP_DATAINPUT */
+
+/*
+ * We have received a packet that the decompressor failed to
+ * decompress. Issue a reset-request.
+ */
+void ccp_resetrequest(ppp_pcb *pcb) {
+    fsm *f = &pcb->ccp_fsm;
+
+    if (f->state != PPP_FSM_OPENED)
+	return;
+
+    /*
+     * Send a reset-request to reset the peer's compressor.
+     * We don't do that if we are still waiting for an
+     * acknowledgement to a previous reset-request.
+     */
+    if (!(pcb->ccp_localstate & RACK_PENDING)) {
+	fsm_sdata(f, CCP_RESETREQ, f->reqid = ++f->id, NULL, 0);
+	TIMEOUT(ccp_rack_timeout, f, RACKTIMEOUT);
+	pcb->ccp_localstate |= RACK_PENDING;
+    } else
+	pcb->ccp_localstate |= RREQ_REPEAT;
+}
+
+/*
+ * Timeout waiting for reset-ack.
+ */
+static void ccp_rack_timeout(void *arg) {
+    fsm *f = (fsm*)arg;
+    ppp_pcb *pcb = f->pcb;
+
+    if (f->state == PPP_FSM_OPENED && (pcb->ccp_localstate & RREQ_REPEAT)) {
+	fsm_sdata(f, CCP_RESETREQ, f->reqid, NULL, 0);
+	TIMEOUT(ccp_rack_timeout, f, RACKTIMEOUT);
+	pcb->ccp_localstate &= ~RREQ_REPEAT;
+    } else
+	pcb->ccp_localstate &= ~RACK_PENDING;
+}
+
+#endif /* PPP_SUPPORT && CCP_SUPPORT */

http://git-wip-us.apache.org/repos/asf/incubator-mynewt-core/blob/f5a0f2a0/net/ip/lwip_base/src/netif/ppp/chap-md5.c
----------------------------------------------------------------------
diff --git a/net/ip/lwip_base/src/netif/ppp/chap-md5.c b/net/ip/lwip_base/src/netif/ppp/chap-md5.c
new file mode 100644
index 0000000..88f069f
--- /dev/null
+++ b/net/ip/lwip_base/src/netif/ppp/chap-md5.c
@@ -0,0 +1,126 @@
+/*
+ * chap-md5.c - New CHAP/MD5 implementation.
+ *
+ * Copyright (c) 2003 Paul Mackerras. 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. The name(s) of the authors of this software must not be used to
+ *    endorse or promote products derived from this software without
+ *    prior written permission.
+ *
+ * 3. Redistributions of any form whatsoever must retain the following
+ *    acknowledgment:
+ *    "This product includes software developed by Paul Mackerras
+ *     <pa...@samba.org>".
+ *
+ * THE AUTHORS OF THIS SOFTWARE DISCLAIM ALL WARRANTIES WITH REGARD TO
+ * THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
+ * AND FITNESS, IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY
+ * SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN
+ * AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING
+ * OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#include "netif/ppp/ppp_opts.h"
+#if PPP_SUPPORT && CHAP_SUPPORT  /* don't build if not configured for use in lwipopts.h */
+
+#if 0 /* UNUSED */
+#include <stdlib.h>
+#include <string.h>
+#endif /* UNUSED */
+
+#include "netif/ppp/ppp_impl.h"
+
+#include "netif/ppp/chap-new.h"
+#include "netif/ppp/chap-md5.h"
+#include "netif/ppp/magic.h"
+#include "netif/ppp/pppcrypt.h"
+
+#define MD5_HASH_SIZE		16
+#define MD5_MIN_CHALLENGE	17
+#define MD5_MAX_CHALLENGE	24
+#define MD5_MIN_MAX_POWER_OF_TWO_CHALLENGE     3   /* 2^3-1 = 7, 17+7 = 24 */
+
+#if PPP_SERVER
+static void chap_md5_generate_challenge(ppp_pcb *pcb, unsigned char *cp) {
+	int clen;
+	LWIP_UNUSED_ARG(pcb);
+
+	clen = MD5_MIN_CHALLENGE + magic_pow(MD5_MIN_MAX_POWER_OF_TWO_CHALLENGE);
+	*cp++ = clen;
+	magic_random_bytes(cp, clen);
+}
+
+static int chap_md5_verify_response(ppp_pcb *pcb, int id, const char *name,
+			 const unsigned char *secret, int secret_len,
+			 const unsigned char *challenge, const unsigned char *response,
+			 char *message, int message_space) {
+	lwip_md5_context ctx;
+	unsigned char idbyte = id;
+	unsigned char hash[MD5_HASH_SIZE];
+	int challenge_len, response_len;
+	LWIP_UNUSED_ARG(name);
+	LWIP_UNUSED_ARG(pcb);
+
+	challenge_len = *challenge++;
+	response_len = *response++;
+	if (response_len == MD5_HASH_SIZE) {
+		/* Generate hash of ID, secret, challenge */
+		lwip_md5_init(&ctx);
+		lwip_md5_starts(&ctx);
+		lwip_md5_update(&ctx, &idbyte, 1);
+		lwip_md5_update(&ctx, secret, secret_len);
+		lwip_md5_update(&ctx, challenge, challenge_len);
+		lwip_md5_finish(&ctx, hash);
+		lwip_md5_free(&ctx);
+
+		/* Test if our hash matches the peer's response */
+		if (memcmp(hash, response, MD5_HASH_SIZE) == 0) {
+			ppp_slprintf(message, message_space, "Access granted");
+			return 1;
+		}
+	}
+	ppp_slprintf(message, message_space, "Access denied");
+	return 0;
+}
+#endif /* PPP_SERVER */
+
+static void chap_md5_make_response(ppp_pcb *pcb, unsigned char *response, int id, const char *our_name,
+		       const unsigned char *challenge, const char *secret, int secret_len,
+		       unsigned char *private_) {
+	lwip_md5_context ctx;
+	unsigned char idbyte = id;
+	int challenge_len = *challenge++;
+	LWIP_UNUSED_ARG(our_name);
+	LWIP_UNUSED_ARG(private_);
+	LWIP_UNUSED_ARG(pcb);
+
+	lwip_md5_init(&ctx);
+	lwip_md5_starts(&ctx);
+	lwip_md5_update(&ctx, &idbyte, 1);
+	lwip_md5_update(&ctx, (const u_char *)secret, secret_len);
+	lwip_md5_update(&ctx, challenge, challenge_len);
+	lwip_md5_finish(&ctx, &response[1]);
+	lwip_md5_free(&ctx);
+	response[0] = MD5_HASH_SIZE;
+}
+
+const struct chap_digest_type md5_digest = {
+	CHAP_MD5,		/* code */
+#if PPP_SERVER
+	chap_md5_generate_challenge,
+	chap_md5_verify_response,
+#endif /* PPP_SERVER */
+	chap_md5_make_response,
+	NULL,			/* check_success */
+	NULL,			/* handle_failure */
+};
+
+#endif /* PPP_SUPPORT && CHAP_SUPPORT */

http://git-wip-us.apache.org/repos/asf/incubator-mynewt-core/blob/f5a0f2a0/net/ip/lwip_base/src/netif/ppp/chap-new.c
----------------------------------------------------------------------
diff --git a/net/ip/lwip_base/src/netif/ppp/chap-new.c b/net/ip/lwip_base/src/netif/ppp/chap-new.c
new file mode 100644
index 0000000..485122d
--- /dev/null
+++ b/net/ip/lwip_base/src/netif/ppp/chap-new.c
@@ -0,0 +1,677 @@
+/*
+ * chap-new.c - New CHAP implementation.
+ *
+ * Copyright (c) 2003 Paul Mackerras. 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. The name(s) of the authors of this software must not be used to
+ *    endorse or promote products derived from this software without
+ *    prior written permission.
+ *
+ * 3. Redistributions of any form whatsoever must retain the following
+ *    acknowledgment:
+ *    "This product includes software developed by Paul Mackerras
+ *     <pa...@samba.org>".
+ *
+ * THE AUTHORS OF THIS SOFTWARE DISCLAIM ALL WARRANTIES WITH REGARD TO
+ * THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
+ * AND FITNESS, IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY
+ * SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN
+ * AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING
+ * OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#include "netif/ppp/ppp_opts.h"
+#if PPP_SUPPORT && CHAP_SUPPORT  /* don't build if not configured for use in lwipopts.h */
+
+#if 0 /* UNUSED */
+#include <stdlib.h>
+#include <string.h>
+#endif /* UNUSED */
+
+#include "netif/ppp/ppp_impl.h"
+
+#if 0 /* UNUSED */
+#include "session.h"
+#endif /* UNUSED */
+
+#include "netif/ppp/chap-new.h"
+#include "netif/ppp/chap-md5.h"
+#if MSCHAP_SUPPORT
+#include "netif/ppp/chap_ms.h"
+#endif
+#include "netif/ppp/magic.h"
+
+#if 0 /* UNUSED */
+/* Hook for a plugin to validate CHAP challenge */
+int (*chap_verify_hook)(const char *name, const char *ourname, int id,
+			const struct chap_digest_type *digest,
+			const unsigned char *challenge, const unsigned char *response,
+			char *message, int message_space) = NULL;
+#endif /* UNUSED */
+
+#if PPP_OPTIONS
+/*
+ * Command-line options.
+ */
+static option_t chap_option_list[] = {
+	{ "chap-restart", o_int, &chap_timeout_time,
+	  "Set timeout for CHAP", OPT_PRIO },
+	{ "chap-max-challenge", o_int, &pcb->settings.chap_max_transmits,
+	  "Set max #xmits for challenge", OPT_PRIO },
+	{ "chap-interval", o_int, &pcb->settings.chap_rechallenge_time,
+	  "Set interval for rechallenge", OPT_PRIO },
+	{ NULL }
+};
+#endif /* PPP_OPTIONS */
+
+
+/* Values for flags in chap_client_state and chap_server_state */
+#define LOWERUP			1
+#define AUTH_STARTED		2
+#define AUTH_DONE		4
+#define AUTH_FAILED		8
+#define TIMEOUT_PENDING		0x10
+#define CHALLENGE_VALID		0x20
+
+/*
+ * Prototypes.
+ */
+static void chap_init(ppp_pcb *pcb);
+static void chap_lowerup(ppp_pcb *pcb);
+static void chap_lowerdown(ppp_pcb *pcb);
+#if PPP_SERVER
+static void chap_timeout(void *arg);
+static void chap_generate_challenge(ppp_pcb *pcb);
+static void chap_handle_response(ppp_pcb *pcb, int code,
+		unsigned char *pkt, int len);
+static int chap_verify_response(ppp_pcb *pcb, const char *name, const char *ourname, int id,
+		const struct chap_digest_type *digest,
+		const unsigned char *challenge, const unsigned char *response,
+		char *message, int message_space);
+#endif /* PPP_SERVER */
+static void chap_respond(ppp_pcb *pcb, int id,
+		unsigned char *pkt, int len);
+static void chap_handle_status(ppp_pcb *pcb, int code, int id,
+		unsigned char *pkt, int len);
+static void chap_protrej(ppp_pcb *pcb);
+static void chap_input(ppp_pcb *pcb, unsigned char *pkt, int pktlen);
+#if PRINTPKT_SUPPORT
+static int chap_print_pkt(const unsigned char *p, int plen,
+		void (*printer) (void *, const char *, ...), void *arg);
+#endif /* PRINTPKT_SUPPORT */
+
+/* List of digest types that we know about */
+static const struct chap_digest_type* const chap_digests[] = {
+    &md5_digest,
+#if MSCHAP_SUPPORT
+    &chapms_digest,
+    &chapms2_digest,
+#endif /* MSCHAP_SUPPORT */
+    NULL
+};
+
+/*
+ * chap_init - reset to initial state.
+ */
+static void chap_init(ppp_pcb *pcb) {
+	LWIP_UNUSED_ARG(pcb);
+
+#if 0 /* Not necessary, everything is cleared in ppp_new() */
+	memset(&pcb->chap_client, 0, sizeof(chap_client_state));
+#if PPP_SERVER
+	memset(&pcb->chap_server, 0, sizeof(chap_server_state));
+#endif /* PPP_SERVER */
+#endif /* 0 */
+}
+
+/*
+ * chap_lowerup - we can start doing stuff now.
+ */
+static void chap_lowerup(ppp_pcb *pcb) {
+
+	pcb->chap_client.flags |= LOWERUP;
+#if PPP_SERVER
+	pcb->chap_server.flags |= LOWERUP;
+	if (pcb->chap_server.flags & AUTH_STARTED)
+		chap_timeout(pcb);
+#endif /* PPP_SERVER */
+}
+
+static void chap_lowerdown(ppp_pcb *pcb) {
+
+	pcb->chap_client.flags = 0;
+#if PPP_SERVER
+	if (pcb->chap_server.flags & TIMEOUT_PENDING)
+		UNTIMEOUT(chap_timeout, pcb);
+	pcb->chap_server.flags = 0;
+#endif /* PPP_SERVER */
+}
+
+#if PPP_SERVER
+/*
+ * chap_auth_peer - Start authenticating the peer.
+ * If the lower layer is already up, we start sending challenges,
+ * otherwise we wait for the lower layer to come up.
+ */
+void chap_auth_peer(ppp_pcb *pcb, const char *our_name, int digest_code) {
+	const struct chap_digest_type *dp;
+	int i;
+
+	if (pcb->chap_server.flags & AUTH_STARTED) {
+		ppp_error("CHAP: peer authentication already started!");
+		return;
+	}
+	for (i = 0; (dp = chap_digests[i]) != NULL; ++i)
+		if (dp->code == digest_code)
+			break;
+	if (dp == NULL)
+		ppp_fatal("CHAP digest 0x%x requested but not available",
+		      digest_code);
+
+	pcb->chap_server.digest = dp;
+	pcb->chap_server.name = our_name;
+	/* Start with a random ID value */
+	pcb->chap_server.id = magic();
+	pcb->chap_server.flags |= AUTH_STARTED;
+	if (pcb->chap_server.flags & LOWERUP)
+		chap_timeout(pcb);
+}
+#endif /* PPP_SERVER */
+
+/*
+ * chap_auth_with_peer - Prepare to authenticate ourselves to the peer.
+ * There isn't much to do until we receive a challenge.
+ */
+void chap_auth_with_peer(ppp_pcb *pcb, const char *our_name, int digest_code) {
+	const struct chap_digest_type *dp;
+	int i;
+
+	if(NULL == our_name)
+		return;
+
+	if (pcb->chap_client.flags & AUTH_STARTED) {
+		ppp_error("CHAP: authentication with peer already started!");
+		return;
+	}
+	for (i = 0; (dp = chap_digests[i]) != NULL; ++i)
+		if (dp->code == digest_code)
+			break;
+
+	if (dp == NULL)
+		ppp_fatal("CHAP digest 0x%x requested but not available",
+		      digest_code);
+
+	pcb->chap_client.digest = dp;
+	pcb->chap_client.name = our_name;
+	pcb->chap_client.flags |= AUTH_STARTED;
+}
+
+#if PPP_SERVER
+/*
+ * chap_timeout - It's time to send another challenge to the peer.
+ * This could be either a retransmission of a previous challenge,
+ * or a new challenge to start re-authentication.
+ */
+static void chap_timeout(void *arg) {
+	ppp_pcb *pcb = (ppp_pcb*)arg;
+	struct pbuf *p;
+
+	pcb->chap_server.flags &= ~TIMEOUT_PENDING;
+	if ((pcb->chap_server.flags & CHALLENGE_VALID) == 0) {
+		pcb->chap_server.challenge_xmits = 0;
+		chap_generate_challenge(pcb);
+		pcb->chap_server.flags |= CHALLENGE_VALID;
+	} else if (pcb->chap_server.challenge_xmits >= pcb->settings.chap_max_transmits) {
+		pcb->chap_server.flags &= ~CHALLENGE_VALID;
+		pcb->chap_server.flags |= AUTH_DONE | AUTH_FAILED;
+		auth_peer_fail(pcb, PPP_CHAP);
+		return;
+	}
+
+	p = pbuf_alloc(PBUF_RAW, (u16_t)(pcb->chap_server.challenge_pktlen), PPP_CTRL_PBUF_TYPE);
+	if(NULL == p)
+		return;
+	if(p->tot_len != p->len) {
+		pbuf_free(p);
+		return;
+	}
+	MEMCPY(p->payload, pcb->chap_server.challenge, pcb->chap_server.challenge_pktlen);
+	ppp_write(pcb, p);
+	++pcb->chap_server.challenge_xmits;
+	pcb->chap_server.flags |= TIMEOUT_PENDING;
+	TIMEOUT(chap_timeout, arg, pcb->settings.chap_timeout_time);
+}
+
+/*
+ * chap_generate_challenge - generate a challenge string and format
+ * the challenge packet in pcb->chap_server.challenge_pkt.
+ */
+static void chap_generate_challenge(ppp_pcb *pcb) {
+	int clen = 1, nlen, len;
+	unsigned char *p;
+
+	p = pcb->chap_server.challenge;
+	MAKEHEADER(p, PPP_CHAP);
+	p += CHAP_HDRLEN;
+	pcb->chap_server.digest->generate_challenge(pcb, p);
+	clen = *p;
+	nlen = strlen(pcb->chap_server.name);
+	memcpy(p + 1 + clen, pcb->chap_server.name, nlen);
+
+	len = CHAP_HDRLEN + 1 + clen + nlen;
+	pcb->chap_server.challenge_pktlen = PPP_HDRLEN + len;
+
+	p = pcb->chap_server.challenge + PPP_HDRLEN;
+	p[0] = CHAP_CHALLENGE;
+	p[1] = ++pcb->chap_server.id;
+	p[2] = len >> 8;
+	p[3] = len;
+}
+
+/*
+ * chap_handle_response - check the response to our challenge.
+ */
+static void  chap_handle_response(ppp_pcb *pcb, int id,
+		     unsigned char *pkt, int len) {
+	int response_len, ok, mlen;
+	const unsigned char *response;
+	unsigned char *outp;
+	struct pbuf *p;
+	const char *name = NULL;	/* initialized to shut gcc up */
+#if 0 /* UNUSED */
+	int (*verifier)(const char *, const char *, int, const struct chap_digest_type *,
+		const unsigned char *, const unsigned char *, char *, int);
+#endif /* UNUSED */
+	char rname[MAXNAMELEN+1];
+	char message[256];
+
+	if ((pcb->chap_server.flags & LOWERUP) == 0)
+		return;
+	if (id != pcb->chap_server.challenge[PPP_HDRLEN+1] || len < 2)
+		return;
+	if (pcb->chap_server.flags & CHALLENGE_VALID) {
+		response = pkt;
+		GETCHAR(response_len, pkt);
+		len -= response_len + 1;	/* length of name */
+		name = (char *)pkt + response_len;
+		if (len < 0)
+			return;
+
+		if (pcb->chap_server.flags & TIMEOUT_PENDING) {
+			pcb->chap_server.flags &= ~TIMEOUT_PENDING;
+			UNTIMEOUT(chap_timeout, pcb);
+		}
+#if PPP_REMOTENAME
+		if (pcb->settings.explicit_remote) {
+			name = pcb->remote_name;
+		} else
+#endif /* PPP_REMOTENAME */
+		{
+			/* Null terminate and clean remote name. */
+			ppp_slprintf(rname, sizeof(rname), "%.*v", len, name);
+			name = rname;
+		}
+
+#if 0 /* UNUSED */
+		if (chap_verify_hook)
+			verifier = chap_verify_hook;
+		else
+			verifier = chap_verify_response;
+		ok = (*verifier)(name, pcb->chap_server.name, id, pcb->chap_server.digest,
+				 pcb->chap_server.challenge + PPP_HDRLEN + CHAP_HDRLEN,
+				 response, pcb->chap_server.message, sizeof(pcb->chap_server.message));
+#endif /* UNUSED */
+		ok = chap_verify_response(pcb, name, pcb->chap_server.name, id, pcb->chap_server.digest,
+                    pcb->chap_server.challenge + PPP_HDRLEN + CHAP_HDRLEN,
+                    response, message, sizeof(message));
+#if 0 /* UNUSED */
+		if (!ok || !auth_number()) {
+#endif /* UNUSED */
+		if (!ok) {
+			pcb->chap_server.flags |= AUTH_FAILED;
+			ppp_warn("Peer %q failed CHAP authentication", name);
+		}
+	} else if ((pcb->chap_server.flags & AUTH_DONE) == 0)
+		return;
+
+	/* send the response */
+	mlen = strlen(message);
+	len = CHAP_HDRLEN + mlen;
+	p = pbuf_alloc(PBUF_RAW, (u16_t)(PPP_HDRLEN +len), PPP_CTRL_PBUF_TYPE);
+	if(NULL == p)
+		return;
+	if(p->tot_len != p->len) {
+		pbuf_free(p);
+		return;
+	}
+
+	outp = (unsigned char *)p->payload;
+	MAKEHEADER(outp, PPP_CHAP);
+
+	outp[0] = (pcb->chap_server.flags & AUTH_FAILED)? CHAP_FAILURE: CHAP_SUCCESS;
+	outp[1] = id;
+	outp[2] = len >> 8;
+	outp[3] = len;
+	if (mlen > 0)
+		memcpy(outp + CHAP_HDRLEN, message, mlen);
+	ppp_write(pcb, p);
+
+	if (pcb->chap_server.flags & CHALLENGE_VALID) {
+		pcb->chap_server.flags &= ~CHALLENGE_VALID;
+		if (!(pcb->chap_server.flags & AUTH_DONE) && !(pcb->chap_server.flags & AUTH_FAILED)) {
+
+#if 0 /* UNUSED */
+		    /*
+		     * Auth is OK, so now we need to check session restrictions
+		     * to ensure everything is OK, but only if we used a
+		     * plugin, and only if we're configured to check.  This
+		     * allows us to do PAM checks on PPP servers that
+		     * authenticate against ActiveDirectory, and use AD for
+		     * account info (like when using Winbind integrated with
+		     * PAM).
+		     */
+		    if (session_mgmt &&
+			session_check(name, NULL, devnam, NULL) == 0) {
+			pcb->chap_server.flags |= AUTH_FAILED;
+			ppp_warn("Peer %q failed CHAP Session verification", name);
+		    }
+#endif /* UNUSED */
+
+		}
+		if (pcb->chap_server.flags & AUTH_FAILED) {
+			auth_peer_fail(pcb, PPP_CHAP);
+		} else {
+			if ((pcb->chap_server.flags & AUTH_DONE) == 0)
+				auth_peer_success(pcb, PPP_CHAP,
+						  pcb->chap_server.digest->code,
+						  name, strlen(name));
+			if (pcb->settings.chap_rechallenge_time) {
+				pcb->chap_server.flags |= TIMEOUT_PENDING;
+				TIMEOUT(chap_timeout, pcb,
+					pcb->settings.chap_rechallenge_time);
+			}
+		}
+		pcb->chap_server.flags |= AUTH_DONE;
+	}
+}
+
+/*
+ * chap_verify_response - check whether the peer's response matches
+ * what we think it should be.  Returns 1 if it does (authentication
+ * succeeded), or 0 if it doesn't.
+ */
+static int chap_verify_response(ppp_pcb *pcb, const char *name, const char *ourname, int id,
+		     const struct chap_digest_type *digest,
+		     const unsigned char *challenge, const unsigned char *response,
+		     char *message, int message_space) {
+	int ok;
+	unsigned char secret[MAXSECRETLEN];
+	int secret_len;
+
+	/* Get the secret that the peer is supposed to know */
+	if (!get_secret(pcb, name, ourname, (char *)secret, &secret_len, 1)) {
+		ppp_error("No CHAP secret found for authenticating %q", name);
+		return 0;
+	}
+	ok = digest->verify_response(pcb, id, name, secret, secret_len, challenge,
+				     response, message, message_space);
+	memset(secret, 0, sizeof(secret));
+
+	return ok;
+}
+#endif /* PPP_SERVER */
+
+/*
+ * chap_respond - Generate and send a response to a challenge.
+ */
+static void chap_respond(ppp_pcb *pcb, int id,
+	     unsigned char *pkt, int len) {
+	int clen, nlen;
+	int secret_len;
+	struct pbuf *p;
+	u_char *outp;
+	char rname[MAXNAMELEN+1];
+	char secret[MAXSECRETLEN+1];
+
+	p = pbuf_alloc(PBUF_RAW, (u16_t)(RESP_MAX_PKTLEN), PPP_CTRL_PBUF_TYPE);
+	if(NULL == p)
+		return;
+	if(p->tot_len != p->len) {
+		pbuf_free(p);
+		return;
+	}
+
+	if ((pcb->chap_client.flags & (LOWERUP | AUTH_STARTED)) != (LOWERUP | AUTH_STARTED))
+		return;		/* not ready */
+	if (len < 2 || len < pkt[0] + 1)
+		return;		/* too short */
+	clen = pkt[0];
+	nlen = len - (clen + 1);
+
+	/* Null terminate and clean remote name. */
+	ppp_slprintf(rname, sizeof(rname), "%.*v", nlen, pkt + clen + 1);
+
+#if PPP_REMOTENAME
+	/* Microsoft doesn't send their name back in the PPP packet */
+	if (pcb->settings.explicit_remote || (pcb->settings.remote_name[0] != 0 && rname[0] == 0))
+		strlcpy(rname, pcb->settings.remote_name, sizeof(rname));
+#endif /* PPP_REMOTENAME */
+
+	/* get secret for authenticating ourselves with the specified host */
+	if (!get_secret(pcb, pcb->chap_client.name, rname, secret, &secret_len, 0)) {
+		secret_len = 0;	/* assume null secret if can't find one */
+		ppp_warn("No CHAP secret found for authenticating us to %q", rname);
+	}
+
+	outp = (u_char*)p->payload;
+	MAKEHEADER(outp, PPP_CHAP);
+	outp += CHAP_HDRLEN;
+
+	pcb->chap_client.digest->make_response(pcb, outp, id, pcb->chap_client.name, pkt,
+				  secret, secret_len, pcb->chap_client.priv);
+	memset(secret, 0, secret_len);
+
+	clen = *outp;
+	nlen = strlen(pcb->chap_client.name);
+	memcpy(outp + clen + 1, pcb->chap_client.name, nlen);
+
+	outp = (u_char*)p->payload + PPP_HDRLEN;
+	len = CHAP_HDRLEN + clen + 1 + nlen;
+	outp[0] = CHAP_RESPONSE;
+	outp[1] = id;
+	outp[2] = len >> 8;
+	outp[3] = len;
+
+	pbuf_realloc(p, PPP_HDRLEN + len);
+	ppp_write(pcb, p);
+}
+
+static void chap_handle_status(ppp_pcb *pcb, int code, int id,
+		   unsigned char *pkt, int len) {
+	const char *msg = NULL;
+	LWIP_UNUSED_ARG(id);
+
+	if ((pcb->chap_client.flags & (AUTH_DONE|AUTH_STARTED|LOWERUP))
+	    != (AUTH_STARTED|LOWERUP))
+		return;
+	pcb->chap_client.flags |= AUTH_DONE;
+
+	if (code == CHAP_SUCCESS) {
+		/* used for MS-CHAP v2 mutual auth, yuck */
+		if (pcb->chap_client.digest->check_success != NULL) {
+			if (!(*pcb->chap_client.digest->check_success)(pcb, pkt, len, pcb->chap_client.priv))
+				code = CHAP_FAILURE;
+		} else
+			msg = "CHAP authentication succeeded";
+	} else {
+		if (pcb->chap_client.digest->handle_failure != NULL)
+			(*pcb->chap_client.digest->handle_failure)(pcb, pkt, len);
+		else
+			msg = "CHAP authentication failed";
+	}
+	if (msg) {
+		if (len > 0)
+			ppp_info("%s: %.*v", msg, len, pkt);
+		else
+			ppp_info("%s", msg);
+	}
+	if (code == CHAP_SUCCESS)
+		auth_withpeer_success(pcb, PPP_CHAP, pcb->chap_client.digest->code);
+	else {
+		pcb->chap_client.flags |= AUTH_FAILED;
+		ppp_error("CHAP authentication failed");
+		auth_withpeer_fail(pcb, PPP_CHAP);
+	}
+}
+
+static void chap_input(ppp_pcb *pcb, unsigned char *pkt, int pktlen) {
+	unsigned char code, id;
+	int len;
+
+	if (pktlen < CHAP_HDRLEN)
+		return;
+	GETCHAR(code, pkt);
+	GETCHAR(id, pkt);
+	GETSHORT(len, pkt);
+	if (len < CHAP_HDRLEN || len > pktlen)
+		return;
+	len -= CHAP_HDRLEN;
+
+	switch (code) {
+	case CHAP_CHALLENGE:
+		chap_respond(pcb, id, pkt, len);
+		break;
+#if PPP_SERVER
+	case CHAP_RESPONSE:
+		chap_handle_response(pcb, id, pkt, len);
+		break;
+#endif /* PPP_SERVER */
+	case CHAP_FAILURE:
+	case CHAP_SUCCESS:
+		chap_handle_status(pcb, code, id, pkt, len);
+		break;
+	default:
+		break;
+	}
+}
+
+static void chap_protrej(ppp_pcb *pcb) {
+
+#if PPP_SERVER
+	if (pcb->chap_server.flags & TIMEOUT_PENDING) {
+		pcb->chap_server.flags &= ~TIMEOUT_PENDING;
+		UNTIMEOUT(chap_timeout, pcb);
+	}
+	if (pcb->chap_server.flags & AUTH_STARTED) {
+		pcb->chap_server.flags = 0;
+		auth_peer_fail(pcb, PPP_CHAP);
+	}
+#endif /* PPP_SERVER */
+	if ((pcb->chap_client.flags & (AUTH_STARTED|AUTH_DONE)) == AUTH_STARTED) {
+		pcb->chap_client.flags &= ~AUTH_STARTED;
+		ppp_error("CHAP authentication failed due to protocol-reject");
+		auth_withpeer_fail(pcb, PPP_CHAP);
+	}
+}
+
+#if PRINTPKT_SUPPORT
+/*
+ * chap_print_pkt - print the contents of a CHAP packet.
+ */
+static const char* const chap_code_names[] = {
+	"Challenge", "Response", "Success", "Failure"
+};
+
+static int chap_print_pkt(const unsigned char *p, int plen,
+	       void (*printer) (void *, const char *, ...), void *arg) {
+	int code, id, len;
+	int clen, nlen;
+	unsigned char x;
+
+	if (plen < CHAP_HDRLEN)
+		return 0;
+	GETCHAR(code, p);
+	GETCHAR(id, p);
+	GETSHORT(len, p);
+	if (len < CHAP_HDRLEN || len > plen)
+		return 0;
+
+	if (code >= 1 && code <= (int)LWIP_ARRAYSIZE(chap_code_names))
+		printer(arg, " %s", chap_code_names[code-1]);
+	else
+		printer(arg, " code=0x%x", code);
+	printer(arg, " id=0x%x", id);
+	len -= CHAP_HDRLEN;
+	switch (code) {
+	case CHAP_CHALLENGE:
+	case CHAP_RESPONSE:
+		if (len < 1)
+			break;
+		clen = p[0];
+		if (len < clen + 1)
+			break;
+		++p;
+		nlen = len - clen - 1;
+		printer(arg, " <");
+		for (; clen > 0; --clen) {
+			GETCHAR(x, p);
+			printer(arg, "%.2x", x);
+		}
+		printer(arg, ">, name = ");
+		ppp_print_string(p, nlen, printer, arg);
+		break;
+	case CHAP_FAILURE:
+	case CHAP_SUCCESS:
+		printer(arg, " ");
+		ppp_print_string(p, len, printer, arg);
+		break;
+	default:
+		for (clen = len; clen > 0; --clen) {
+			GETCHAR(x, p);
+			printer(arg, " %.2x", x);
+		}
+		/* no break */
+	}
+
+	return len + CHAP_HDRLEN;
+}
+#endif /* PRINTPKT_SUPPORT */
+
+const struct protent chap_protent = {
+	PPP_CHAP,
+	chap_init,
+	chap_input,
+	chap_protrej,
+	chap_lowerup,
+	chap_lowerdown,
+	NULL,		/* open */
+	NULL,		/* close */
+#if PRINTPKT_SUPPORT
+	chap_print_pkt,
+#endif /* PRINTPKT_SUPPORT */
+#if PPP_DATAINPUT
+	NULL,		/* datainput */
+#endif /* PPP_DATAINPUT */
+#if PRINTPKT_SUPPORT
+	"CHAP",		/* name */
+	NULL,		/* data_name */
+#endif /* PRINTPKT_SUPPORT */
+#if PPP_OPTIONS
+	chap_option_list,
+	NULL,		/* check_options */
+#endif /* PPP_OPTIONS */
+#if DEMAND_SUPPORT
+	NULL,
+	NULL
+#endif /* DEMAND_SUPPORT */
+};
+
+#endif /* PPP_SUPPORT && CHAP_SUPPORT */