/*
* ccp.c - PPP Compression Control Protocol.
*
* Copyright (c) 2000 by Sun Microsystems, Inc.
* All rights reserved.
*
* Copyright (c) 1994 The Australian National University.
* All rights reserved.
*
* Permission to use, copy, modify, and distribute this software and its
* documentation is hereby granted, provided that the above copyright
* notice appears in all copies. This software is provided without any
* warranty, express or implied. The Australian National University
* makes no representations about the suitability of this software for
* any purpose.
*
* IN NO EVENT SHALL THE AUSTRALIAN NATIONAL UNIVERSITY BE LIABLE TO ANY
* PARTY FOR DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
* ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN IF
* THE AUSTRALIAN NATIONAL UNIVERSITY HAVE BEEN ADVISED OF THE POSSIBILITY
* OF SUCH DAMAGE.
*
* THE AUSTRALIAN NATIONAL UNIVERSITY SPECIFICALLY DISCLAIMS ANY WARRANTIES,
* INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
* AND FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS
* ON AN "AS IS" BASIS, AND THE AUSTRALIAN NATIONAL UNIVERSITY HAS NO
* OBLIGATION TO PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS,
* OR MODIFICATIONS.
*/
/*
* Copyright (c) 2016 by Delphix. All rights reserved.
*/
#include <stdlib.h>
#include <string.h>
#include "pppd.h"
#include "fsm.h"
#include "ccp.h"
#include <net/ppp-comp.h>
/*
* Command-line options.
*/
static int setbsdcomp __P((char **, option_t *));
static int setdeflate __P((char **, option_t *));
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" },
{ "bsdcomp", o_special, (void *)setbsdcomp,
"Request BSD-Compress packet compression" },
{ "nobsdcomp", o_bool, &ccp_wantoptions[0].bsd_compress,
"don't allow BSD-Compress", OPT_A2COPY,
&ccp_allowoptions[0].bsd_compress },
{ "-bsdcomp", o_bool, &ccp_wantoptions[0].bsd_compress,
"don't allow BSD-Compress", OPT_A2COPY,
&ccp_allowoptions[0].bsd_compress },
{ "deflate", o_special, (void *)setdeflate,
"request Deflate compression" },
{ "nodeflate", o_bool, &ccp_wantoptions[0].deflate,
"don't allow Deflate compression", OPT_A2COPY,
&ccp_allowoptions[0].deflate },
{ "-deflate", o_bool, &ccp_wantoptions[0].deflate,
"don't allow Deflate compression", OPT_A2COPY,
&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", 1, &ccp_allowoptions[0].predictor_1 },
{ "nopredictor1", o_bool, &ccp_wantoptions[0].predictor_1,
"don't allow Predictor-1", OPT_A2COPY,
&ccp_allowoptions[0].predictor_1 },
{ "-predictor1", o_bool, &ccp_wantoptions[0].predictor_1,
"don't allow Predictor-1", OPT_A2COPY,
&ccp_allowoptions[0].predictor_1 },
{ NULL }
};
/*
* Protocol entry points from main code.
*/
static void ccp_init __P((int unit));
static void ccp_open __P((int unit));
static void ccp_close __P((int unit, char *));
static void ccp_lowerup __P((int unit));
static void ccp_lowerdown __P((int));
static void ccp_input __P((int unit, u_char *pkt, int len));
static void ccp_protrej __P((int unit));
static int ccp_printpkt __P((u_char *pkt, int len,
void (*printer) __P((void *, const char *, ...)),
void *arg));
static void ccp_datainput __P((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 __P((fsm *));
static int ccp_cilen __P((fsm *));
static void ccp_addci __P((fsm *, u_char *, int *));
static int ccp_ackci __P((fsm *, u_char *, int));
static int ccp_nakci __P((fsm *, u_char *, int));
static int ccp_rejci __P((fsm *, u_char *, int));
static int ccp_reqci __P((fsm *, u_char *, int *, int));
static void ccp_up __P((fsm *));
static void ccp_down __P((fsm *));
static int ccp_extcode __P((fsm *, int, int, u_char *, int));
static int ccp_codereject __P((fsm *p, int code, int id, u_char *inp,
int len));
static fsm_callbacks ccp_callbacks = {
ccp_resetci, /* Reset our Configuration Information */
ccp_cilen, /* Length of our Configuration Information */
ccp_addci, /* Add our Configuration Information */
ccp_ackci, /* ACK our Configuration Information */
ccp_nakci, /* NAK our Configuration Information */
ccp_rejci, /* Reject our Configuration Information */
ccp_reqci, /* Request peer's Configuration Information */
ccp_up, /* Called when fsm reaches OPENED state */
ccp_down, /* Called when fsm leaves OPENED state */
NULL, /* Called when we want the lower layer up */
NULL, /* Called when we want the lower layer down */
NULL, /* Retransmission is necessary */
ccp_extcode, /* Called to handle LCP-specific codes */
"CCP", /* String name of protocol */
ccp_codereject, /* Peer rejected a code number */
};
/*
* Local statics.
*/
static void ccp_rack_timeout __P((void *));
static char * method_name __P((ccp_options *, ccp_options *));
/*
* 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 0x0001 /* waiting for reset-ack */
#define RREQ_REPEAT 0x0002 /* send another reset-req if no reset-ack */
#define RREQ_REJECTED 0x0004 /* peer code-rejected reset-request */
#define RACK_REJECTED 0x0008 /* peer code-rejected reset-ack */
#define RREQ_IGNORED 0x0010 /* peer just ignored reset-request */
#define RACKTIMEOUT 1 /* time in seconds between Reset-Requests */
static int all_rejected[NUM_PPP]; /* we rejected all peer's options */
#ifdef COMP_TUNE
static int deflate_tune = -1; /* compression effort level for deflate */
#endif
static int deflate_rmax = DEFLATE_MAX_SIZE; /* max rbits */
static int deflate_amax = DEFLATE_MAX_SIZE; /* max abits */
/*
* Option parsing.
*/
/*ARGSUSED*/
static int
setbsdcomp(argv, opt)
char **argv;
option_t *opt;
{
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;
return 1;
}
/*ARGSUSED*/
static int
setdeflate(argv, opt)
char **argv;
option_t *opt;
{
int rbits, abits, def_rmax, def_amax;
char *str, *endp;
str = endp = *argv;
if (*str == ',')
abits = rbits = -1;
else
abits = rbits = strtol(str, &endp, 0);
if (*endp == ',') {
str = ++endp;
if (*str == ',')
abits = rbits;
else
abits = strtol(str, &endp, 0);
}
#ifdef COMP_TUNE
if (*endp == ',' && privileged_option) {
str = ++endp;
deflate_tune = strtol(str, &endp, 0);
}
#endif
if (*endp != '\0' || endp == str) {
option_error("invalid parameter '%s' for deflate option", *argv);
return 0;
}
if (privileged_option) {
def_rmax = def_amax = DEFLATE_MAX_SIZE;
} else {
def_rmax = deflate_rmax;
def_amax = deflate_amax;
}
if (rbits < 0)
rbits = def_rmax;
if (abits < 0)
abits = def_amax;
if ((rbits != 0 && (rbits <= DEFLATE_MIN_SIZE || rbits > def_rmax))
|| (abits != 0 && (abits <= DEFLATE_MIN_SIZE || abits > def_amax))) {
option_error("deflate option values must be 0 or {%d,%d} .. {%d,%d}",
DEFLATE_MIN_SIZE+1, DEFLATE_MIN_SIZE+1,
def_rmax, def_amax);
return 0;
}
if (privileged_option) {
deflate_rmax = rbits;
deflate_amax = abits;
}
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;
return 1;
}
/*
* 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);
f->flags |= OPT_RESTART;
BZERO(&ccp_wantoptions[unit], sizeof(ccp_options));
BZERO(&ccp_gotoptions[unit], sizeof(ccp_options));
BZERO(&ccp_allowoptions[unit], sizeof(ccp_options));
BZERO(&ccp_hisoptions[unit], 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 we haven't gone open yet (first time through), then go open
* but not up. Otherwise, skip this to allow reopen to reset the
* compressor.
*/
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] == CODE_TERMREQ && f->state != OPENED)
notice("Compression disabled by peer.");
/*
* If we get a terminate-ack and we're not asking for compression,
* close CCP. (Terminate-Request is handled by fsm_input() above.)
*/
if (oldstate == REQSENT && p[0] == CODE_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 not open, then silently ignore. */
if (f->state != OPENED)
break;
/* send a reset-ack, which our transmitter module will see and
reset its compression state. */
fsm_sdata(f, CCP_RESETACK, id, p, len);
break;
case CCP_RESETACK:
/*
* Note that the compression module isn't picky about ID
* numbers and such.
*/
ccp_localstate[f->unit] &= ~RREQ_IGNORED & ~RREQ_REJECTED;
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:
/* Tell fsm to send code reject */
return (0);
}
return (1);
}
/*
* Handle Code-Reject for one of our extended codes by dropping back to
* reopen as mechanism to restart compression.
*/
/*ARGSUSED*/
static int
ccp_codereject(f, code, id, inp, len)
fsm *f;
int code, id;
u_char *inp;
int len;
{
switch (code) {
case CCP_RESETREQ:
if (!(ccp_localstate[f->unit] & RREQ_REJECTED)) {
info("peer has rejected CCP Reset-Request; falling back on Open");
if (f->state == OPENED)
ccp_open(f->unit);
}
ccp_localstate[f->unit] |= RREQ_REJECTED;
return (0);
case CCP_RESETACK:
/*
* Peer must have sent us CCP Reset-Request but then code-rejected when
* we sent CCP Reset-Ack. It seems to have changed its mind, and we
* have to obey its wishes.
*/
ccp_localstate[f->unit] |= RACK_REJECTED;
notice("peer has erroneously rejected CCP Reset-Ack");
f->term_reason = "peer sent Code-Reject for CCP Reset-Ack";
f->term_reason_len = strlen(f->term_reason);
break;
default:
f->term_reason = "peer sent invalid Code-Reject";
break;
}
f->term_reason_len = strlen(f->term_reason);
return (1);
}
/*
* ccp_protrej - peer doesn't talk CCP.
*/
static void
ccp_protrej(unit)
int unit;
{
/* Neither open nor up. */
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
* decompression 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+1);
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+1);
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 && 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);
}
/*
* 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+1) {
go->deflate = 0;
break;
}
--go->deflate_size;
p[2] = DEFLATE_MAKE_OPT(go->deflate_size);
}
/* If we're offering both, then this is second. */
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);
}
}
}
/*
* Prefer Predictor-1 over Predictor-2. (The latter requires the use
* of LAP-B and has no known implementations.)
*/
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 && go->deflate_correct) {
if (len < CILEN_DEFLATE
|| p[0] != CI_DEFLATE || p[1] != CILEN_DEFLATE
|| p[2] != DEFLATE_MAKE_OPT(go->deflate_size)
|| p[3] != DEFLATE_CHK_SEQUENCE)
return 0;
/* Cope with non-standard first/fast ack */
if (p == p0 && len == 0)
return 1;
p += CILEN_DEFLATE;
len -= CILEN_DEFLATE;
}
if (go->deflate && 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;
/* Cope with non-standard first/fast ack */
if (p == p0 && len == 0)
return 1;
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;
/* Cope with non-standard first/fast ack */
if (p == p0 && len == 0)
return 1;
p += CILEN_BSD_COMPRESS;
len -= CILEN_BSD_COMPRESS;
}
if (go->predictor_1) {
if (len < CILEN_PREDICTOR_1
|| p[0] != CI_PREDICTOR_1 || p[1] != CILEN_PREDICTOR_1)
return 0;
/* Cope with non-standard first/fast ack */
if (p == p0 && len == 0)
return 1;
p += CILEN_PREDICTOR_1;
len -= CILEN_PREDICTOR_1;
}
if (go->predictor_2) {
if (len < CILEN_PREDICTOR_2
|| p[0] != CI_PREDICTOR_2 || p[1] != CILEN_PREDICTOR_2)
return 0;
/* Cope with non-standard first/fast ack */
if (p == p0 && len == 0)
return 1;
p += CILEN_PREDICTOR_2;
len -= CILEN_PREDICTOR_2;
}
/* Peer cannot ack something that wasn't sent. */
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 */
BZERO(&no, sizeof(no));
try = *go;
if (go->deflate && go->deflate_correct && len >= CILEN_DEFLATE &&
p[0] == CI_DEFLATE) {
no.deflate = 1;
/*
* Peer wants us to use a different code size or something.
* Stop asking for Deflate if we don't understand its suggestion.
*/
if (p[1] != CILEN_DEFLATE
|| DEFLATE_METHOD(p[2]) != DEFLATE_METHOD_VAL
|| DEFLATE_SIZE(p[2]) <= DEFLATE_MIN_SIZE
|| p[3] != DEFLATE_CHK_SEQUENCE)
try.deflate_correct = 0;
else if (DEFLATE_SIZE(p[2]) < go->deflate_size)
try.deflate_size = DEFLATE_SIZE(p[2]);
len -= p[1];
p += p[1];
}
if (go->deflate && go->deflate_draft && len >= CILEN_DEFLATE &&
p[0] == CI_DEFLATE_DRAFT) {
no.deflate = 1;
/*
* Peer wants us to use a different code size or something.
* Stop asking for Deflate using the old algorithm number if
* we don't understand its suggestion. (Note that this will
* happen if the peer is running Magnalink instead of
* old-style Deflate.)
*/
if (p[1] != CILEN_DEFLATE
|| DEFLATE_METHOD(p[2]) != DEFLATE_METHOD_VAL
|| DEFLATE_SIZE(p[2]) <= DEFLATE_MIN_SIZE
|| p[3] != DEFLATE_CHK_SEQUENCE)
try.deflate_draft = 0;
else if (DEFLATE_SIZE(p[2]) < go->deflate_size)
try.deflate_size = DEFLATE_SIZE(p[2]);
len -= p[1];
p += p[1];
}
if (!try.deflate_correct && !try.deflate_draft)
try.deflate = 0;
if (go->bsd_compress && len >= CILEN_BSD_COMPRESS &&
p[0] == CI_BSD_COMPRESS) {
no.bsd_compress = 1;
/*
* Peer wants us to use a different number of bits
* or a different version.
*/
if (p[1] != CILEN_BSD_COMPRESS ||
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]);
len -= p[1];
p += p[1];
}
/*
* 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 - peer rejects 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 && 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 && 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 - process a received configure-request.
*
* Returns CODE_CONFACK, CODE_CONFNAK or CODE_CONFREJ and the packet
* is 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, *nakp, *rejp, *pv;
int len, clen, type, nb;
ccp_options *ho = &ccp_hisoptions[f->unit];
ccp_options *ao = &ccp_allowoptions[f->unit];
ret = CODE_CONFACK;
rejp = p0 = p;
nakp = nak_buffer;
len = *lenp;
BZERO(ho, sizeof(ccp_options));
ho->method = (len > 0)? p[0]: -1;
for (; len > 0; len -= clen, p += clen) {
newret = CODE_CONFACK;
if (len < 2 || p[1] > len) {
/*
* RFC 1661 page 40 -- if the option extends beyond the
* packet, then discard the entire packet.
*/
return (0);
}
type = p[0];
clen = p[1];
pv = p;
switch (type) {
case CI_DEFLATE:
case CI_DEFLATE_DRAFT:
if (!ao->deflate ||
(!ao->deflate_correct && type == CI_DEFLATE) ||
(!ao->deflate_draft && type == CI_DEFLATE_DRAFT)) {
newret = CODE_CONFREJ;
break;
}
ho->deflate = 1;
nb = clen < CILEN_DEFLATE ? ao->deflate_size : DEFLATE_SIZE(p[2]);
ho->deflate_size = nb;
if (clen != CILEN_DEFLATE ||
DEFLATE_METHOD(p[2]) != DEFLATE_METHOD_VAL ||
p[3] != DEFLATE_CHK_SEQUENCE || nb > ao->deflate_size ||
nb <= DEFLATE_MIN_SIZE) {
newret = CODE_CONFNAK;
if (dont_nak)
break;
if (nb > ao->deflate_size)
nb = ao->deflate_size;
else if (nb <= DEFLATE_MIN_SIZE)
nb = DEFLATE_MIN_SIZE+1;
pv = nakp;
PUTCHAR(type, nakp);
PUTCHAR(CILEN_DEFLATE, nakp);
PUTCHAR(DEFLATE_MAKE_OPT(nb), nakp);
PUTCHAR(DEFLATE_CHK_SEQUENCE, nakp);
}
/*
* 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, pv, CILEN_DEFLATE, 1);
if (res > 0)
break; /* it's OK now */
if (res < 0 || nb <= DEFLATE_MIN_SIZE+1 || dont_nak) {
newret = CODE_CONFREJ;
break;
}
if (newret == CODE_CONFACK) {
BCOPY(pv, nakp, CILEN_DEFLATE);
pv = nakp;
nakp += CILEN_DEFLATE;
newret = CODE_CONFNAK;
}
--nb;
pv[2] = DEFLATE_MAKE_OPT(nb);
}
#ifdef COMP_TUNE
/* Tune Deflate compression effort. */
if (newret == CODE_CONFACK)
ccp_tune(f->unit, deflate_tune);
#endif
}
break;
case CI_BSD_COMPRESS:
if (!ao->bsd_compress) {
newret = CODE_CONFREJ;
break;
}
ho->bsd_compress = 1;
nb = clen < CILEN_BSD_COMPRESS ? ao->bsd_bits : BSD_NBITS(p[2]);
ho->bsd_bits = nb;
if (clen != CILEN_BSD_COMPRESS ||
BSD_VERSION(p[2]) != BSD_CURRENT_VERSION ||
nb > ao->bsd_bits || nb < BSD_MIN_BITS) {
newret = CODE_CONFNAK;
if (dont_nak)
break;
if (nb > ao->bsd_bits)
nb = ao->bsd_bits;
else if (nb < BSD_MIN_BITS)
nb = BSD_MIN_BITS;
pv = nakp;
PUTCHAR(type, nakp);
PUTCHAR(CILEN_BSD_COMPRESS, nakp);
PUTCHAR(BSD_MAKE_OPT(BSD_CURRENT_VERSION, nb), nakp);
}
/*
* 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, pv, CILEN_BSD_COMPRESS, 1);
if (res > 0)
break;
if (res < 0 || nb == BSD_MIN_BITS || dont_nak) {
newret = CODE_CONFREJ;
break;
}
if (newret == CODE_CONFACK) {
BCOPY(pv, nakp, CILEN_BSD_COMPRESS);
pv = nakp;
nakp += CILEN_BSD_COMPRESS;
newret = CODE_CONFNAK;
}
--nb;
pv[2] = BSD_MAKE_OPT(BSD_CURRENT_VERSION, nb);
}
}
break;
case CI_PREDICTOR_1:
if (!ao->predictor_1) {
newret = CODE_CONFREJ;
break;
}
ho->predictor_1 = 1;
if (clen != CILEN_PREDICTOR_1) {
newret = CODE_CONFNAK;
if (dont_nak)
break;
pv = nakp;
PUTCHAR(type, nakp);
PUTCHAR(CILEN_PREDICTOR_1, nakp);
}
if (p == p0 &&
ccp_test(f->unit, pv, CILEN_PREDICTOR_1, 1) <= 0) {
newret = CODE_CONFREJ;
}
break;
case CI_PREDICTOR_2:
if (!ao->predictor_2) {
newret = CODE_CONFREJ;
break;
}
ho->predictor_2 = 1;
if (clen != CILEN_PREDICTOR_2) {
newret = CODE_CONFNAK;
if (dont_nak)
break;
pv = nakp;
PUTCHAR(type, nakp);
PUTCHAR(CILEN_PREDICTOR_2, nakp);
}
if (p == p0 &&
ccp_test(f->unit, p, CILEN_PREDICTOR_2, 1) <= 0) {
newret = CODE_CONFREJ;
}
break;
default:
newret = CODE_CONFREJ;
break;
}
/* Cope with confused peers. */
if (clen < 2)
clen = 2;
if (newret == CODE_CONFACK && ret != CODE_CONFACK)
continue;
if (newret == CODE_CONFNAK) {
if (dont_nak) {
newret = CODE_CONFREJ;
} else {
/* Ignore subsequent nakable things if rejecting. */
if (ret == CODE_CONFREJ)
continue;
ret = CODE_CONFNAK;
}
}
if (newret == CODE_CONFREJ) {
ret = CODE_CONFREJ;
if (p != rejp)
BCOPY(p, rejp, clen);
rejp += clen;
}
}
switch (ret) {
case CODE_CONFACK:
*lenp = p - p0;
break;
case CODE_CONFNAK:
*lenp = nakp - nak_buffer;
BCOPY(nak_buffer, p0, *lenp);
break;
case CODE_CONFREJ:
*lenp = rejp - p0;
break;
}
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)
(void) slprintf(result, sizeof(result), "Deflate%s (%d/%d)",
(opt->method == CI_DEFLATE_DRAFT? "(old#)": ""),
opt->deflate_size, opt2->deflate_size);
else
(void) 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)
(void) slprintf(result, sizeof(result), "BSD-Compress (%d/%d)",
opt->bsd_bits, opt2->bsd_bits);
else
(void) 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";
#ifdef CI_STAC
case CI_STAC:
return "Stac";
#endif
#ifdef CI_MPPC
case CI_MPPC:
return "MS-PPC";
#endif
default:
(void) 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(f)
fsm *f;
{
ccp_options *go = &ccp_gotoptions[f->unit];
ccp_options *ho = &ccp_hisoptions[f->unit];
char method1[64];
/*
* We're now open and up (running).
*/
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 {
(void) strlcpy(method1, method_name(go, NULL), sizeof(method1));
notice("%s / %s compression enabled",
method1, method_name(ho, NULL));
}
} else
notice("%s receive decompression enabled", method_name(go, NULL));
} else if (ANY_COMPRESS(*ho))
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);
/* Don't forget about peer's code rejects or ignoring of requests. */
ccp_localstate[f->unit] &= ~RACK_PENDING & ~RREQ_REPEAT;
/* We're still open, but no longer up. */
ccp_flags_set(f->unit, 1, 0);
}
static int
ccp_printpkt(p, plen, printer, arg)
u_char *p;
int plen;
void (*printer) __P((void *, const char *, ...));
void *arg;
{
u_char *p0, *optend, cichar;
int code, id, len;
int optlen, clen;
u_short cishort;
#ifdef CI_MPPC
u_int32_t cilong;
#endif
p0 = p;
if (plen < HEADERLEN) {
printer(arg, "too short (%d<%d)", plen, HEADERLEN);
return (0);
}
GETCHAR(code, p);
GETCHAR(id, p);
GETSHORT(len, p);
printer(arg, " %s id=0x%x", code_name(code, 1), id);
if (len < HEADERLEN) {
printer(arg, " header length %d<%d", len, HEADERLEN);
return (HEADERLEN);
}
if (len > plen) {
printer(arg, " truncated (%d>%d)", len, plen);
len = plen;
}
len -= HEADERLEN;
switch (code) {
case CODE_CONFREQ:
case CODE_CONFACK:
case CODE_CONFNAK:
case CODE_CONFREJ:
/* print list of possible compression methods */
while (len >= 2) {
GETCHAR(code, p);
GETCHAR(clen, p);
optlen = clen;
printer(arg, " <");
if (optlen > len)
optlen = len;
if (optlen < 2)
optlen = 2;
len -= optlen;
optend = p + optlen - 2;
switch (code) {
case CI_DEFLATE:
case CI_DEFLATE_DRAFT:
printer(arg, "deflate%s",
(code == CI_DEFLATE_DRAFT? "(old#)": ""));
if (clen != CILEN_DEFLATE)
printer(arg, " length %d", clen);
if (optlen >= CILEN_DEFLATE) {
GETCHAR(cichar, p);
printer(arg, " %d", DEFLATE_SIZE(cichar));
if (DEFLATE_METHOD(cichar) != DEFLATE_METHOD_VAL)
printer(arg, " method %d", DEFLATE_METHOD(cichar));
GETCHAR(cichar, p);
if (cichar != DEFLATE_CHK_SEQUENCE)
printer(arg, " check %d", cichar);
}
break;
case CI_BSD_COMPRESS:
printer(arg, "bsd");
if (clen != CILEN_BSD_COMPRESS)
printer(arg, " length %d", clen);
if (optlen >= CILEN_BSD_COMPRESS) {
GETCHAR(cichar, p);
printer(arg, " v%d %d", BSD_VERSION(cichar),
BSD_NBITS(cichar));
}
break;
case CI_PREDICTOR_1:
printer(arg, "predictor-1");
if (clen != CILEN_PREDICTOR_1)
printer(arg, " length %d", clen);
break;
case CI_PREDICTOR_2:
printer(arg, "predictor-2");
if (clen != CILEN_PREDICTOR_2)
printer(arg, " length %d", clen);
break;
#ifdef CI_STAC
case CI_STAC:
printer(arg, "Stac");
if (clen != CILEN_STAC)
printer(arg, " length %d", clen);
if (optlen >= CILEN_STAC) {
GETSHORT(cishort, p);
GETCHAR(cichar, p);
printer(arg, " h%d/m%d", cishort, cichar);
}
break;
#endif
#ifdef CI_MPPC
case CI_MPPC:
/* There appears to be no good generic name for this one. */
if (optlen >= CILEN_MPPC) {
GETLONG(cilong, p);
if (!(cilong & MPPC_COMP)) {
if (cilong & MPPC_MPPE)
printer(arg, "MPPE");
else
printer(arg, "MS-PPC?");
} else {
if (cilong & MPPC_MPPE)
printer(arg, "MPPC+MPPE");
else
printer(arg, "MPPC");
}
} else {
printer(arg, "MS-?");
}
if (clen != CILEN_STAC)
printer(arg, " length %d", clen);
break;
#endif
default:
printer(arg, "typ%d len%d ", code, clen);
break;
}
if (p < optend) {
if (p+8 < optend)
printer(arg, " %.8B ...", p);
else
printer(arg, " %.*B", optend-p, p);
p = optend;
}
printer(arg, ">");
}
break;
case CODE_TERMACK:
case CODE_TERMREQ:
if (len > 0) {
if (len == 2) {
GETSHORT(cishort, p);
printer(arg, " history %d", cishort);
len = 0;
} else if (*p >= ' ' && *p < 0x7f) {
printer(arg, " ");
print_string((char *)p, len, printer, arg);
p += len;
len = 0;
}
}
break;
}
/* dump out the rest of the packet in hex */
if (len > 0) {
if (len > 8)
printer(arg, " %.8B ...", p);
else
printer(arg, " %.*B", len, p);
p += len;
}
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.
*/
/*ARGSUSED*/
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.
*/
error("Lost compression sync: disabling compression");
ccp_close(unit, "Lost compression sync");
} else {
/*
* Send a reset-request to reset the peer's compressor, if
* possible. We don't do anything if we are still waiting
* for an acknowledgement to a previous reset-request (to
* avoid flooding the peer). We reopen CCP if the peer
* doesn't like hearing about CCP Reset-Request (Cisco
* sends CCP Code-Reject for Reset-Request). (Reopen
* automatically clears the flags and cancels the
* timeout.)
*/
if (ccp_localstate[f->unit] & RREQ_REJECTED) {
dbglog("reopening CCP to reset peer's compressor");
ccp_open(f->unit);
} else if (ccp_localstate[f->unit] & RACK_PENDING) {
/* Send another reset request; we're out of sequence. */
ccp_localstate[f->unit] |= RREQ_REPEAT;
} else {
dbglog("sending CCP Reset-Request to reset peer's compressor");
fsm_sdata(f, CCP_RESETREQ, f->reqid = ++f->id, NULL, 0);
TIMEOUT(ccp_rack_timeout, f, RACKTIMEOUT);
ccp_localstate[f->unit] |= RACK_PENDING;
}
}
}
}
/*
* Timeout waiting for reset-ack.
*/
static void
ccp_rack_timeout(arg)
void *arg;
{
fsm *f = arg;
/* Timeout; no longer pending. */
ccp_localstate[f->unit] &= ~RACK_PENDING;
/* Frankly, it's a coding flaw if this occurs. */
if (f->state != OPENED)
return;
if (ccp_localstate[f->unit] & RREQ_IGNORED) {
info("peer ignored our CCP Reset-Request twice; reopen instead");
ccp_localstate[f->unit] =
(ccp_localstate[f->unit] & ~RREQ_IGNORED) | RREQ_REJECTED;
ccp_open(f->unit);
} else if (ccp_localstate[f->unit] & RREQ_REPEAT) {
dbglog("sending another CCP Reset-Request on timeout");
fsm_sdata(f, CCP_RESETREQ, f->reqid, NULL, 0);
TIMEOUT(ccp_rack_timeout, f, RACKTIMEOUT);
ccp_localstate[f->unit] =
(ccp_localstate[f->unit] & ~RREQ_REPEAT) | RREQ_IGNORED |
RACK_PENDING;
} else {
dbglog("timeout waiting for CCP Reset-Ack; hope for the best");
ccp_localstate[f->unit] |= RREQ_IGNORED;
}
}