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/*
* 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
* <paulus@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.
*/
#define RCSID "$Id: ccp.c,v 1.50 2005/06/26 19:34:41 carlsonj Exp $"
#include <stdlib.h>
#include <string.h>
#include "pppd.h"
#include "fsm.h"
#include "ccp.h"
#include <net/ppp-comp.h>
#ifdef MPPE
#include "chap_ms.h" /* mppe_xxxx_key, mppe_keys_set */
#include "lcp.h" /* lcp_close(), lcp_fsm */
#endif
/*
* 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.
*/
static int setbsdcomp (char **);
static int setdeflate (char **);
static char bsd_value[8];
static char deflate_value[8];
/*
* Option variables.
*/
#ifdef MPPE
bool refuse_mppe_stateful = 1; /* Allow stateful mode? */
#endif
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 },
#ifdef MPPE
/* 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 */
{ NULL }
};
/*
* Protocol entry points from main code.
*/
static void ccp_init (int unit);
static void ccp_open (int unit);
static void ccp_close (int unit, char *);
static void ccp_lowerup (int unit);
static void ccp_lowerdown (int);
static void ccp_input (int unit, u_char *pkt, int len);
static void ccp_protrej (int unit);
static int ccp_printpkt (u_char *pkt, int len,
void (*printer)(void *, char *, ...),
void *arg);
static void ccp_datainput (int unit, u_char *pkt, int len);
struct protent ccp_protent = {
PPP_CCP,
ccp_init,
ccp_input,
ccp_protrej,
ccp_lowerup,
ccp_lowerdown,
ccp_open,
ccp_close,
ccp_printpkt,
ccp_datainput,
1,
"CCP",
"Compressed",
ccp_option_list,
NULL,
NULL,
NULL
};
fsm ccp_fsm[NUM_PPP];
ccp_options ccp_wantoptions[NUM_PPP]; /* what to request the peer to use */
ccp_options ccp_gotoptions[NUM_PPP]; /* what the peer agreed to do */
ccp_options ccp_allowoptions[NUM_PPP]; /* what we'll agree to do */
ccp_options ccp_hisoptions[NUM_PPP]; /* what we agreed to do */
/*
* 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 char *method_name (ccp_options *, ccp_options *);
static 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?
*/
#define ANY_COMPRESS(opt) ((opt).deflate || (opt).bsd_compress \
|| (opt).predictor_1 || (opt).predictor_2 \
|| (opt).mppe)
/*
* Local state (mainly for handling reset-reqs and reset-acks).
*/
static int ccp_localstate[NUM_PPP];
#define RACK_PENDING 1 /* waiting for reset-ack */
#define RREQ_REPEAT 2 /* send another reset-req if no reset-ack */
#define RACKTIMEOUT 1 /* second */
static int all_rejected[NUM_PPP]; /* we rejected all peer's options */
/*
* Option parsing.
*/
static int
setbsdcomp(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;
slprintf(bsd_value, sizeof(bsd_value),
rbits == abits? "%d": "%d,%d", rbits, abits);
return 1;
}
static int
setdeflate(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;
slprintf(deflate_value, sizeof(deflate_value),
rbits == abits? "%d": "%d,%d", rbits, abits);
return 1;
}
/*
* ccp_init - initialize CCP.
*/
static void
ccp_init(int unit)
{
fsm *f = &ccp_fsm[unit];
f->unit = unit;
f->protocol = PPP_CCP;
f->callbacks = &ccp_callbacks;
fsm_init(f);
memset(&ccp_wantoptions[unit], 0, sizeof(ccp_options));
memset(&ccp_gotoptions[unit], 0, sizeof(ccp_options));
memset(&ccp_allowoptions[unit], 0, sizeof(ccp_options));
memset(&ccp_hisoptions[unit], 0, sizeof(ccp_options));
ccp_wantoptions[0].deflate = 1;
ccp_wantoptions[0].deflate_size = DEFLATE_MAX_SIZE;
ccp_wantoptions[0].deflate_correct = 1;
ccp_wantoptions[0].deflate_draft = 1;
ccp_allowoptions[0].deflate = 1;
ccp_allowoptions[0].deflate_size = DEFLATE_MAX_SIZE;
ccp_allowoptions[0].deflate_correct = 1;
ccp_allowoptions[0].deflate_draft = 1;
ccp_wantoptions[0].bsd_compress = 1;
ccp_wantoptions[0].bsd_bits = BSD_MAX_BITS;
ccp_allowoptions[0].bsd_compress = 1;
ccp_allowoptions[0].bsd_bits = BSD_MAX_BITS;
ccp_allowoptions[0].predictor_1 = 1;
}
/*
* ccp_open - CCP is allowed to come up.
*/
static void
ccp_open(int unit)
{
fsm *f = &ccp_fsm[unit];
if (f->state != OPENED)
ccp_flags_set(unit, 1, 0);
/*
* Find out which compressors the kernel supports before
* deciding whether to open in silent mode.
*/
ccp_resetci(f);
if (!ANY_COMPRESS(ccp_gotoptions[unit]))
f->flags |= OPT_SILENT;
fsm_open(f);
}
/*
* ccp_close - Terminate CCP.
*/
static void
ccp_close(int unit, char *reason)
{
ccp_flags_set(unit, 0, 0);
fsm_close(&ccp_fsm[unit], reason);
}
/*
* ccp_lowerup - we may now transmit CCP packets.
*/
static void
ccp_lowerup(int unit)
{
fsm_lowerup(&ccp_fsm[unit]);
}
/*
* ccp_lowerdown - we may not transmit CCP packets.
*/
static void
ccp_lowerdown(int unit)
{
fsm_lowerdown(&ccp_fsm[unit]);
}
/*
* ccp_input - process a received CCP packet.
*/
static void
ccp_input(int unit, u_char *p, int len)
{
fsm *f = &ccp_fsm[unit];
int oldstate;
/*
* Check for a terminate-request so we can print a message.
*/
oldstate = f->state;
fsm_input(f, p, len);
if (oldstate == OPENED && p[0] == TERMREQ && f->state != OPENED) {
notice("Compression disabled by peer.");
#ifdef MPPE
if (ccp_gotoptions[unit].mppe) {
error("MPPE disabled, closing LCP");
lcp_close(unit, "MPPE disabled by peer");
}
#endif
}
/*
* If we get a terminate-ack and we're not asking for compression,
* close CCP.
*/
if (oldstate == REQSENT && p[0] == TERMACK
&& !ANY_COMPRESS(ccp_gotoptions[unit]))
ccp_close(unit, "No compression negotiated");
}
/*
* Handle a CCP-specific code.
*/
static int
ccp_extcode(fsm *f, int code, int id, u_char *p, int len)
{
switch (code) {
case CCP_RESETREQ:
if (f->state != OPENED)
break;
/* 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 (ccp_localstate[f->unit] & RACK_PENDING && id == f->reqid) {
ccp_localstate[f->unit] &= ~(RACK_PENDING | RREQ_REPEAT);
UNTIMEOUT(ccp_rack_timeout, f);
}
break;
default:
return 0;
}
return 1;
}
/*
* ccp_protrej - peer doesn't talk CCP.
*/
static void
ccp_protrej(int unit)
{
ccp_flags_set(unit, 0, 0);
fsm_lowerdown(&ccp_fsm[unit]);
#ifdef MPPE
if (ccp_gotoptions[unit].mppe) {
error("MPPE required but peer negotiation failed");
lcp_close(unit, "MPPE required but peer negotiation failed");
}
#endif
}
/*
* ccp_resetci - initialize at start of negotiation.
*/
static void
ccp_resetci(fsm *f)
{
ccp_options *go = &ccp_gotoptions[f->unit];
u_char opt_buf[CCP_MAX_OPTION_LENGTH];
*go = ccp_wantoptions[f->unit];
all_rejected[f->unit] = 0;
#ifdef MPPE
if (go->mppe) {
ccp_options *ao = &ccp_allowoptions[f->unit];
int auth_mschap_bits = auth_done[f->unit];
#ifdef USE_EAPTLS
int auth_eap_bits = auth_done[f->unit];
#endif
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) {
error("MPPE required, but auth done in both directions.");
lcp_close(f->unit, "MPPE required but not available");
return;
}
#ifdef USE_EAPTLS
/*
* MPPE is also possible in combination with EAP-TLS.
* It is not possible to detect if we're doing EAP or EAP-TLS
* at this stage, hence we accept all forms of EAP. If TLS is
* not used then the MPPE keys will not be derived anyway.
*/
/* Leave only the eap auth bits set */
auth_eap_bits &= (EAP_WITHPEER | EAP_PEER );
if ((numbits == 0) && (auth_eap_bits == 0)) {
error("MPPE required, but MS-CHAP[v2] nor EAP-TLS auth are performed.");
#else
if (!numbits) {
error("MPPE required, but MS-CHAP[v2] auth not performed.");
#endif
lcp_close(f->unit, "MPPE required but not available");
return;
}
/* A plugin (eg radius) may not have obtained key material. */
if (!mppe_keys_set) {
error("MPPE required, but keys are not available. "
"Possible plugin problem?");
lcp_close(f->unit, "MPPE required but not available");
return;
}
/* LM auth not supported for MPPE */
if (auth_done[f->unit] & (CHAP_MS_WITHPEER | CHAP_MS_PEER)) {
/* This might be noise */
if (go->mppe & MPPE_OPT_40) {
notice("Disabling 40-bit MPPE; MS-CHAP LM not supported");
go->mppe &= ~MPPE_OPT_40;
ccp_wantoptions[f->unit].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. */
error("MPPE required, but both 40-bit and 128-bit disabled.");
lcp_close(f->unit, "MPPE required but not available");
return;
}
/* sync options */
ao->mppe = go->mppe;
/* MPPE is not compatible with other compression types */
ao->bsd_compress = go->bsd_compress = 0;
ao->predictor_1 = go->predictor_1 = 0;
ao->predictor_2 = go->predictor_2 = 0;
ao->deflate = go->deflate = 0;
}
#endif /* MPPE */
/*
* Check whether the kernel knows about the various
* compression methods we might request.
*/
#ifdef MPPE
if (go->mppe) {
opt_buf[0] = CI_MPPE;
opt_buf[1] = CILEN_MPPE;
MPPE_OPTS_TO_CI(go->mppe, &opt_buf[2]);
/* Key material unimportant here. */
if (ccp_test(f->unit, opt_buf, CILEN_MPPE + MPPE_MAX_KEY_LEN, 0) <= 0) {
error("MPPE required, but kernel has no support.");
lcp_close(f->unit, "MPPE required but not available");
}
}
#endif
if (go->bsd_compress) {
opt_buf[0] = CI_BSD_COMPRESS;
opt_buf[1] = CILEN_BSD_COMPRESS;
opt_buf[2] = BSD_MAKE_OPT(BSD_CURRENT_VERSION, BSD_MIN_BITS);
if (ccp_test(f->unit, opt_buf, CILEN_BSD_COMPRESS, 0) <= 0)
go->bsd_compress = 0;
}
if (go->deflate) {
if (go->deflate_correct) {
opt_buf[0] = CI_DEFLATE;
opt_buf[1] = CILEN_DEFLATE;
opt_buf[2] = DEFLATE_MAKE_OPT(DEFLATE_MIN_WORKS);
opt_buf[3] = DEFLATE_CHK_SEQUENCE;
if (ccp_test(f->unit, opt_buf, CILEN_DEFLATE, 0) <= 0)
go->deflate_correct = 0;
}
if (go->deflate_draft) {
opt_buf[0] = CI_DEFLATE_DRAFT;
opt_buf[1] = CILEN_DEFLATE;
opt_buf[2] = DEFLATE_MAKE_OPT(DEFLATE_MIN_WORKS);
opt_buf[3] = DEFLATE_CHK_SEQUENCE;
if (ccp_test(f->unit, opt_buf, CILEN_DEFLATE, 0) <= 0)
go->deflate_draft = 0;
}
if (!go->deflate_correct && !go->deflate_draft)
go->deflate = 0;
}
if (go->predictor_1) {
opt_buf[0] = CI_PREDICTOR_1;
opt_buf[1] = CILEN_PREDICTOR_1;
if (ccp_test(f->unit, 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(f->unit, opt_buf, CILEN_PREDICTOR_2, 0) <= 0)
go->predictor_2 = 0;
}
}
/*
* ccp_cilen - Return total length of our configuration info.
*/
static int
ccp_cilen(fsm *f)
{
ccp_options *go = &ccp_gotoptions[f->unit];
return (go->bsd_compress? CILEN_BSD_COMPRESS: 0)
+ (go->deflate && go->deflate_correct? CILEN_DEFLATE: 0)
+ (go->deflate && go->deflate_draft? CILEN_DEFLATE: 0)
+ (go->predictor_1? CILEN_PREDICTOR_1: 0)
+ (go->predictor_2? CILEN_PREDICTOR_2: 0)
+ (go->mppe? CILEN_MPPE: 0);
}
/*
* ccp_addci - put our requests in a packet.
*/
static void
ccp_addci(fsm *f, u_char *p, int *lenp)
{
int res;
ccp_options *go = &ccp_gotoptions[f->unit];
u_char *p0 = p;
/*
* Add the compression types that we can receive, in decreasing
* preference order. Get the kernel to allocate the first one
* in case it gets Acked.
*/
#ifdef MPPE
if (go->mppe) {
u_char opt_buf[CILEN_MPPE + MPPE_MAX_KEY_LEN];
p[0] = opt_buf[0] = CI_MPPE;
p[1] = opt_buf[1] = CILEN_MPPE;
MPPE_OPTS_TO_CI(go->mppe, &p[2]);
MPPE_OPTS_TO_CI(go->mppe, &opt_buf[2]);
BCOPY(mppe_recv_key, &opt_buf[CILEN_MPPE], MPPE_MAX_KEY_LEN);
res = ccp_test(f->unit, opt_buf, CILEN_MPPE + MPPE_MAX_KEY_LEN, 0);
if (res > 0)
p += CILEN_MPPE;
else
/* This shouldn't happen, we've already tested it! */
lcp_close(f->unit, "MPPE required but not available in kernel");
}
#endif
if (go->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;
if (p != p0) {
p += CILEN_DEFLATE;
} else {
for (;;) {
if (go->deflate_size < DEFLATE_MIN_WORKS) {
go->deflate = 0;
break;
}
res = ccp_test(f->unit, p, CILEN_DEFLATE, 0);
if (res > 0) {
p += CILEN_DEFLATE;
break;
} else if (res < 0) {
go->deflate = 0;
break;
}
--go->deflate_size;
p[2] = DEFLATE_MAKE_OPT(go->deflate_size);
}
}
if (p != p0 && go->deflate_correct && 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;
}
}
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);
if (p != p0) {
p += CILEN_BSD_COMPRESS; /* not the first option */
} else {
for (;;) {
if (go->bsd_bits < BSD_MIN_BITS) {
go->bsd_compress = 0;
break;
}
res = ccp_test(f->unit, p, CILEN_BSD_COMPRESS, 0);
if (res > 0) {
p += CILEN_BSD_COMPRESS;
break;
} else if (res < 0) {
go->bsd_compress = 0;
break;
}
--go->bsd_bits;
p[2] = BSD_MAKE_OPT(BSD_CURRENT_VERSION, go->bsd_bits);
}
}
}
/* XXX Should Predictor 2 be preferable to Predictor 1? */
if (go->predictor_1) {
p[0] = CI_PREDICTOR_1;
p[1] = CILEN_PREDICTOR_1;
if (p == p0 && ccp_test(f->unit, p, CILEN_PREDICTOR_1, 0) <= 0) {
go->predictor_1 = 0;
} else {
p += CILEN_PREDICTOR_1;
}
}
if (go->predictor_2) {
p[0] = CI_PREDICTOR_2;
p[1] = CILEN_PREDICTOR_2;
if (p == p0 && ccp_test(f->unit, p, CILEN_PREDICTOR_2, 0) <= 0) {
go->predictor_2 = 0;
} else {
p += CILEN_PREDICTOR_2;
}
}
go->method = (p > p0)? p0[0]: -1;
*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)
{
ccp_options *go = &ccp_gotoptions[f->unit];
u_char *p0 = p;
#ifdef MPPE
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
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;
}
}
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;
}
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;
}
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)
{
ccp_options *go = &ccp_gotoptions[f->unit];
ccp_options no; /* options we've seen already */
ccp_options try; /* options to ask for next time */
memset(&no, 0, sizeof(no));
try = *go;
#ifdef MPPE
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) && refuse_mppe_stateful) {
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) {
error("MPPE required but peer negotiation failed");
lcp_close(f->unit, "MPPE required but peer negotiation failed");
}
}
#endif /* MPPE */
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;
}
}
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;
}
/*
* 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 != 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)
{
ccp_options *go = &ccp_gotoptions[f->unit];
ccp_options try; /* options to request next time */
try = *go;
/*
* Cope with empty configure-rejects by ceasing to send
* configure-requests.
*/
if (len == 0 && all_rejected[f->unit])
return -1;
#ifdef MPPE
if (go->mppe && len >= CILEN_MPPE
&& p[0] == CI_MPPE && p[1] == CILEN_MPPE) {
error("MPPE required but peer refused");
lcp_close(f->unit, "MPPE required but peer refused");
p += CILEN_MPPE;
len -= CILEN_MPPE;
}
#endif
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;
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;
}
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;
}
if (len != 0)
return 0;
if (f->state != 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)
{
int ret, newret, res;
u_char *p0, *retp;
int len, clen, type, nb;
ccp_options *ho = &ccp_hisoptions[f->unit];
ccp_options *ao = &ccp_allowoptions[f->unit];
#ifdef MPPE
bool rej_for_ci_mppe = 1; /* Are we rejecting based on a bad/missing */
/* CI_MPPE, or due to other options? */
#endif
ret = CONFACK;
retp = p0 = p;
len = *lenp;
memset(ho, 0, sizeof(ccp_options));
ho->method = (len > 0)? p[0]: -1;
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) {
#ifdef MPPE
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 (refuse_mppe_stateful) {
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) {
u_char opt_buf[CILEN_MPPE + MPPE_MAX_KEY_LEN];
int mtu;
BCOPY(p, opt_buf, CILEN_MPPE);
BCOPY(mppe_send_key, &opt_buf[CILEN_MPPE],
MPPE_MAX_KEY_LEN);
if (ccp_test(f->unit, opt_buf,
CILEN_MPPE + MPPE_MAX_KEY_LEN, 1) <= 0) {
/* This shouldn't happen, we've already tested it! */
error("MPPE required, but kernel has no support.");
lcp_close(f->unit, "MPPE required but not available");
newret = CONFREJ;
break;
}
/*
* 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(f->unit);
if (mtu)
netif_set_mtu(f->unit, 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 */
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(f->unit, 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;
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(f->unit, 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;
case CI_PREDICTOR_1:
if (!ao->predictor_1 || clen != CILEN_PREDICTOR_1) {
newret = CONFREJ;
break;
}
ho->predictor_1 = 1;
if (p == p0
&& ccp_test(f->unit, 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(f->unit, p, CILEN_PREDICTOR_2, 1) <= 0) {
newret = CONFREJ;
}
break;
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)
BCOPY(p, retp, clen);
retp += clen;
}
p += clen;
len -= clen;
}
if (ret != CONFACK) {
if (ret == CONFREJ && *lenp == retp - p0)
all_rejected[f->unit] = 1;
else
*lenp = retp - p0;
}
#ifdef MPPE
if (ret == CONFREJ && ao->mppe && rej_for_ci_mppe) {
error("MPPE required but peer negotiation failed");
lcp_close(f->unit, "MPPE required but peer negotiation failed");
}
#endif
return ret;
}
/*
* Make a string name for a compression method (or 2).
*/
static char *
method_name(ccp_options *opt, ccp_options *opt2)
{
static char result[64];
if (!ANY_COMPRESS(*opt))
return "(none)";
switch (opt->method) {
#ifdef MPPE
case CI_MPPE:
{
char *p = result;
char *q = result + sizeof(result); /* 1 past result */
slprintf(p, q - p, "MPPE ");
p += 5;
if (opt->mppe & MPPE_OPT_128) {
slprintf(p, q - p, "128-bit ");
p += 8;
}
if (opt->mppe & MPPE_OPT_40) {
slprintf(p, q - p, "40-bit ");
p += 7;
}
if (opt->mppe & MPPE_OPT_STATEFUL)
slprintf(p, q - p, "stateful");
else
slprintf(p, q - p, "stateless");
break;
}
#endif
case CI_DEFLATE:
case CI_DEFLATE_DRAFT:
if (opt2 != NULL && opt2->deflate_size != opt->deflate_size)
slprintf(result, sizeof(result), "Deflate%s (%d/%d)",
(opt->method == CI_DEFLATE_DRAFT? "(old#)": ""),
opt->deflate_size, opt2->deflate_size);
else
slprintf(result, sizeof(result), "Deflate%s (%d)",
(opt->method == CI_DEFLATE_DRAFT? "(old#)": ""),
opt->deflate_size);
break;
case CI_BSD_COMPRESS:
if (opt2 != NULL && opt2->bsd_bits != opt->bsd_bits)
slprintf(result, sizeof(result), "BSD-Compress (%d/%d)",
opt->bsd_bits, opt2->bsd_bits);
else
slprintf(result, sizeof(result), "BSD-Compress (%d)",
opt->bsd_bits);
break;
case CI_PREDICTOR_1:
return "Predictor 1";
case CI_PREDICTOR_2:
return "Predictor 2";
default:
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)
{
ccp_options *go = &ccp_gotoptions[f->unit];
ccp_options *ho = &ccp_hisoptions[f->unit];
char method1[64];
ccp_flags_set(f->unit, 1, 1);
if (ANY_COMPRESS(*go)) {
if (ANY_COMPRESS(*ho)) {
if (go->method == ho->method) {
notice("%s compression enabled", method_name(go, ho));
} else {
strlcpy(method1, method_name(go, NULL), sizeof(method1));
notice("%s / %s compression enabled",
method1, method_name(ho, NULL));
}
} else
notice("%s receive compression enabled", method_name(go, NULL));
} else if (ANY_COMPRESS(*ho))
notice("%s transmit compression enabled", method_name(ho, NULL));
#ifdef MPPE
if (go->mppe) {
BZERO(mppe_recv_key, MPPE_MAX_KEY_LEN);
BZERO(mppe_send_key, MPPE_MAX_KEY_LEN);
continue_networks(f->unit); /* Bring up IP et al */
}
#endif
}
/*
* CCP has gone down - inform the kernel driver.
*/
static void
ccp_down(fsm *f)
{
if (ccp_localstate[f->unit] & RACK_PENDING)
UNTIMEOUT(ccp_rack_timeout, f);
ccp_localstate[f->unit] = 0;
ccp_flags_set(f->unit, 1, 0);
#ifdef MPPE
if (ccp_gotoptions[f->unit].mppe) {
ccp_gotoptions[f->unit].mppe = 0;
if (lcp_fsm[f->unit].state == OPENED) {
/* If LCP is not already going down, make sure it does. */
error("MPPE disabled");
lcp_close(f->unit, "MPPE disabled");
}
}
#endif
}
/*
* Print the contents of a CCP packet.
*/
static char *ccp_codenames[] = {
"ConfReq", "ConfAck", "ConfNak", "ConfRej",
"TermReq", "TermAck", "CodeRej",
NULL, NULL, NULL, NULL, NULL, NULL,
"ResetReq", "ResetAck",
};
static int
ccp_printpkt(u_char *p, int plen,
void (*printer) (void *, char *, ...), void *arg)
{
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 <= sizeof(ccp_codenames) / sizeof(char *)
&& 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) {
#ifdef MPPE
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
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;
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;
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;
}
while (p < optend)
printer(arg, " %.2x", *p++);
printer(arg, ">");
}
break;
case TERMACK:
case TERMREQ:
if (len > 0 && *p >= ' ' && *p < 0x7f) {
print_string((char *)p, len, printer, arg);
p += len;
len = 0;
}
break;
}
/* dump out the rest of the packet in hex */
while (--len >= 0)
printer(arg, " %.2x", *p++);
return p - p0;
}
/*
* 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(int unit, u_char *pkt, int len)
{
fsm *f;
f = &ccp_fsm[unit];
if (f->state == OPENED) {
if (ccp_fatal_error(unit)) {
/*
* Disable compression by taking CCP down.
*/
error("Lost compression sync: disabling compression");
ccp_close(unit, "Lost compression sync");
#ifdef MPPE
/*
* If we were doing MPPE, we must also take the link down.
*/
if (ccp_gotoptions[unit].mppe) {
error("Too many MPPE errors, closing LCP");
lcp_close(unit, "Too many MPPE errors");
}
#endif
} 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 (!(ccp_localstate[f->unit] & RACK_PENDING)) {
fsm_sdata(f, CCP_RESETREQ, f->reqid = ++f->id, NULL, 0);
TIMEOUT(ccp_rack_timeout, f, RACKTIMEOUT);
ccp_localstate[f->unit] |= RACK_PENDING;
} else
ccp_localstate[f->unit] |= RREQ_REPEAT;
}
}
}
/*
* Timeout waiting for reset-ack.
*/
static void
ccp_rack_timeout(void *arg)
{
fsm *f = arg;
if (f->state == OPENED && ccp_localstate[f->unit] & RREQ_REPEAT) {
fsm_sdata(f, CCP_RESETREQ, f->reqid, NULL, 0);
TIMEOUT(ccp_rack_timeout, f, RACKTIMEOUT);
ccp_localstate[f->unit] &= ~RREQ_REPEAT;
} else
ccp_localstate[f->unit] &= ~RACK_PENDING;
}