File: [local] / src / usr.sbin / pppd / ccp.c (download)
Revision 1.13, Tue Oct 27 23:59:53 2009 UTC (14 years, 7 months ago) by deraadt
Branch: MAIN
CVS Tags: OPENBSD_7_5_BASE, OPENBSD_7_5, OPENBSD_7_4_BASE, OPENBSD_7_4, OPENBSD_7_3_BASE, OPENBSD_7_3, OPENBSD_7_2_BASE, OPENBSD_7_2, OPENBSD_7_1_BASE, OPENBSD_7_1, OPENBSD_7_0_BASE, OPENBSD_7_0, OPENBSD_6_9_BASE, OPENBSD_6_9, OPENBSD_6_8_BASE, OPENBSD_6_8, OPENBSD_6_7_BASE, OPENBSD_6_7, OPENBSD_6_6_BASE, OPENBSD_6_6, OPENBSD_6_5_BASE, OPENBSD_6_5, OPENBSD_6_4_BASE, OPENBSD_6_4, OPENBSD_6_3_BASE, OPENBSD_6_3, OPENBSD_6_2_BASE, OPENBSD_6_2, OPENBSD_6_1_BASE, OPENBSD_6_1, OPENBSD_6_0_BASE, OPENBSD_6_0, OPENBSD_5_9_BASE, OPENBSD_5_9, OPENBSD_5_8_BASE, OPENBSD_5_8, OPENBSD_5_7_BASE, OPENBSD_5_7, OPENBSD_5_6_BASE, OPENBSD_5_6, OPENBSD_5_5_BASE, OPENBSD_5_5, OPENBSD_5_4_BASE, OPENBSD_5_4, OPENBSD_5_3_BASE, OPENBSD_5_3, OPENBSD_5_2_BASE, OPENBSD_5_2, OPENBSD_5_1_BASE, OPENBSD_5_1, OPENBSD_5_0_BASE, OPENBSD_5_0, OPENBSD_4_9_BASE, OPENBSD_4_9, OPENBSD_4_8_BASE, OPENBSD_4_8, OPENBSD_4_7_BASE, OPENBSD_4_7, HEAD
Changes since 1.12: +1 -9 lines
rcsid[] and sccsid[] and copyright[] are essentially unmaintained (and
unmaintainable). these days, people use source. these id's do not provide
any benefit, and do hurt the small install media
(the 33,000 line diff is essentially mechanical)
ok with the idea millert, ok dms
|
/* $OpenBSD: ccp.c,v 1.13 2009/10/27 23:59:53 deraadt Exp $ */
/*
* ccp.c - PPP Compression Control Protocol.
*
* Copyright (c) 1989-2002 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. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
*
* 3. 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.
*
* 4. 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.
*/
#include <string.h>
#include <syslog.h>
#include <sys/ioctl.h>
#include <sys/types.h>
#include "pppd.h"
#include "fsm.h"
#include "ccp.h"
#include <net/ppp-comp.h>
/*
* 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",
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);
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)
/*
* 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 */
/*
* ccp_init - initialize CCP.
*/
static void
ccp_init(unit)
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(unit)
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(unit, reason)
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(unit)
int unit;
{
fsm_lowerup(&ccp_fsm[unit]);
}
/*
* ccp_lowerdown - we may not transmit CCP packets.
*/
static void
ccp_lowerdown(unit)
int unit;
{
fsm_lowerdown(&ccp_fsm[unit]);
}
/*
* ccp_input - process a received CCP packet.
*/
static void
ccp_input(unit, p, len)
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)
syslog(LOG_NOTICE, "Compression disabled by peer.");
/*
* 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(f, code, id, p, len)
fsm *f;
int code, 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(unit)
int unit;
{
ccp_flags_set(unit, 0, 0);
fsm_lowerdown(&ccp_fsm[unit]);
}
/*
* ccp_resetci - initialize at start of negotiation.
*/
static void
ccp_resetci(f)
fsm *f;
{
ccp_options *go = &ccp_gotoptions[f->unit];
u_char opt_buf[16];
*go = ccp_wantoptions[f->unit];
all_rejected[f->unit] = 0;
/*
* Check whether the kernel knows about the various
* compression methods we might request.
*/
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_SIZE);
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_SIZE);
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(f)
fsm *f;
{
ccp_options *go = &ccp_gotoptions[f->unit];
return (go->bsd_compress? CILEN_BSD_COMPRESS: 0)
+ (go->deflate? CILEN_DEFLATE: 0)
+ (go->predictor_1? CILEN_PREDICTOR_1: 0)
+ (go->predictor_2? CILEN_PREDICTOR_2: 0);
}
/*
* ccp_addci - put our requests in a packet.
*/
static void
ccp_addci(f, p, lenp)
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.
*/
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;
for (;;) {
res = ccp_test(f->unit, p, CILEN_DEFLATE, 0);
if (res > 0) {
p += CILEN_DEFLATE;
break;
}
if (res < 0 || go->deflate_size <= DEFLATE_MIN_SIZE) {
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 (;;) {
res = ccp_test(f->unit, p, CILEN_BSD_COMPRESS, 0);
if (res > 0) {
p += CILEN_BSD_COMPRESS;
break;
}
if (res < 0 || go->bsd_bits <= BSD_MIN_BITS) {
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(f, p, len)
fsm *f;
u_char *p;
int len;
{
ccp_options *go = &ccp_gotoptions[f->unit];
u_char *p0 = p;
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(f, p, len)
fsm *f;
u_char *p;
int len;
{
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;
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_SIZE
|| 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.
*
* XXX What should we do with any remaining options?
*/
if (len != 0)
return 0;
if (f->state != OPENED)
*go = try;
return 1;
}
/*
* ccp_rejci - reject some of our suggested compression methods.
*/
static int
ccp_rejci(f, p, len)
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;
if (go->deflate && len >= CILEN_DEFLATE
&& p[0] == (go->deflate_correct? CI_DEFLATE: 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 */
if (go->deflate_correct)
try.deflate_correct = 0;
else
try.deflate_draft = 0;
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) {
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(f, p, lenp, dont_nak)
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];
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) {
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_SIZE) {
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_SIZE || 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;
}
return ret;
}
/*
* Make a string name for a compression method (or 2).
*/
static char *
method_name(opt, opt2)
ccp_options *opt, *opt2;
{
static char result[64];
if (!ANY_COMPRESS(*opt))
return "(none)";
switch (opt->method) {
case CI_DEFLATE:
case CI_DEFLATE_DRAFT:
if (opt2 != NULL && opt2->deflate_size != opt->deflate_size)
snprintf(result, sizeof result, "Deflate%s (%d/%d)",
(opt->method == CI_DEFLATE_DRAFT? "(old#)": ""),
opt->deflate_size, opt2->deflate_size);
else
snprintf(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)
snprintf(result, sizeof result,
"BSD-Compress (%d/%d)", opt->bsd_bits,
opt2->bsd_bits);
else
snprintf(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:
snprintf(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(f)
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) {
syslog(LOG_NOTICE, "%s compression enabled",
method_name(go, ho));
} else {
strncpy(method1, method_name(go, NULL), sizeof method1);
syslog(LOG_NOTICE, "%s / %s compression enabled",
method1, method_name(ho, NULL));
}
} else
syslog(LOG_NOTICE, "%s receive compression enabled",
method_name(go, NULL));
} else if (ANY_COMPRESS(*ho))
syslog(LOG_NOTICE, "%s transmit compression enabled",
method_name(ho, NULL));
}
/*
* CCP has gone down - inform the kernel driver.
*/
static void
ccp_down(f)
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);
}
/*
* 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(p, plen, printer, arg)
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) {
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(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(unit, pkt, len)
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.
*/
syslog(LOG_ERR, "Lost compression sync: disabling compression");
ccp_close(unit, "Lost compression sync");
} 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(arg)
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;
}
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