blob: 27023261edbf7ca0130a33c7e3b50892b1b66d49 [file] [log] [blame]
/*
* ppp_deflate.c - interface the zlib procedures for Deflate compression
* and decompression (as used by gzip) to the PPP code.
* This version is for use with STREAMS under SunOS 4.x, Solaris 2,
* SVR4, OSF/1 and AIX 4.x.
*
* Copyright (c) 1994 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.
*
* $Id: deflate.c,v 1.12 2004/01/17 05:47:55 carlsonj Exp $
*/
#ifdef AIX4
#include <net/net_globals.h>
#endif
#include <sys/param.h>
#include <sys/types.h>
#include <sys/stream.h>
#include <net/ppp_defs.h>
#include "ppp_mod.h"
#define PACKETPTR mblk_t *
#include <net/ppp-comp.h>
#ifdef __osf__
#include "zlib.h"
#else
#include "../common/zlib.h"
#endif
#ifdef SOL2
#include <sys/sunddi.h>
#endif
#if DO_DEFLATE
#define DEFLATE_DEBUG 1
/*
* State for a Deflate (de)compressor.
*/
struct deflate_state {
int seqno;
int w_size;
int unit;
int hdrlen;
int mru;
int debug;
z_stream strm;
struct compstat stats;
};
#define DEFLATE_OVHD 2 /* Deflate overhead/packet */
static void *z_alloc(void *, u_int items, u_int size);
static void *z_alloc_init(void *, u_int items, u_int size);
static void z_free(void *, void *ptr);
static void *z_comp_alloc(u_char *options, int opt_len);
static void *z_decomp_alloc(u_char *options, int opt_len);
static void z_comp_free(void *state);
static void z_decomp_free(void *state);
static int z_comp_init(void *state, u_char *options, int opt_len,
int unit, int hdrlen, int debug);
static int z_decomp_init(void *state, u_char *options, int opt_len,
int unit, int hdrlen, int mru, int debug);
static int z_compress(void *state, mblk_t **mret,
mblk_t *mp, int slen, int maxolen);
static void z_incomp(void *state, mblk_t *dmsg);
static int z_decompress(void *state, mblk_t *cmp,
mblk_t **dmpp);
static void z_comp_reset(void *state);
static void z_decomp_reset(void *state);
static void z_comp_stats(void *state, struct compstat *stats);
/*
* Procedures exported to ppp_comp.c.
*/
struct compressor ppp_deflate = {
CI_DEFLATE, /* compress_proto */
z_comp_alloc, /* comp_alloc */
z_comp_free, /* comp_free */
z_comp_init, /* comp_init */
z_comp_reset, /* comp_reset */
z_compress, /* compress */
z_comp_stats, /* comp_stat */
z_decomp_alloc, /* decomp_alloc */
z_decomp_free, /* decomp_free */
z_decomp_init, /* decomp_init */
z_decomp_reset, /* decomp_reset */
z_decompress, /* decompress */
z_incomp, /* incomp */
z_comp_stats, /* decomp_stat */
};
struct compressor ppp_deflate_draft = {
CI_DEFLATE_DRAFT, /* compress_proto */
z_comp_alloc, /* comp_alloc */
z_comp_free, /* comp_free */
z_comp_init, /* comp_init */
z_comp_reset, /* comp_reset */
z_compress, /* compress */
z_comp_stats, /* comp_stat */
z_decomp_alloc, /* decomp_alloc */
z_decomp_free, /* decomp_free */
z_decomp_init, /* decomp_init */
z_decomp_reset, /* decomp_reset */
z_decompress, /* decompress */
z_incomp, /* incomp */
z_comp_stats, /* decomp_stat */
};
#define DECOMP_CHUNK 512
/*
* Space allocation and freeing routines for use by zlib routines.
*/
struct zchunk {
u_int size;
u_int guard;
};
#define GUARD_MAGIC 0x77a6011a
static void *
z_alloc_init(notused, items, size)
void *notused;
u_int items, size;
{
struct zchunk *z;
size = items * size + sizeof(struct zchunk);
#ifdef __osf__
z = (struct zchunk *) ALLOC_SLEEP(size);
#else
z = (struct zchunk *) ALLOC_NOSLEEP(size);
#endif
z->size = size;
z->guard = GUARD_MAGIC;
return (void *) (z + 1);
}
static void *
z_alloc(notused, items, size)
void *notused;
u_int items, size;
{
struct zchunk *z;
size = items * size + sizeof(struct zchunk);
z = (struct zchunk *) ALLOC_NOSLEEP(size);
z->size = size;
z->guard = GUARD_MAGIC;
return (void *) (z + 1);
}
static void
z_free(notused, ptr)
void *notused;
void *ptr;
{
struct zchunk *z = ((struct zchunk *) ptr) - 1;
if (z->guard != GUARD_MAGIC) {
printf("ppp: z_free of corrupted chunk at %x (%x, %x)\n",
z, z->size, z->guard);
return;
}
FREE(z, z->size);
}
/*
* Allocate space for a compressor.
*/
static void *
z_comp_alloc(options, opt_len)
u_char *options;
int opt_len;
{
struct deflate_state *state;
int w_size;
if (opt_len != CILEN_DEFLATE
|| (options[0] != CI_DEFLATE && options[0] != CI_DEFLATE_DRAFT)
|| options[1] != CILEN_DEFLATE
|| DEFLATE_METHOD(options[2]) != DEFLATE_METHOD_VAL
|| options[3] != DEFLATE_CHK_SEQUENCE)
return NULL;
w_size = DEFLATE_SIZE(options[2]);
/*
* N.B. the 9 below should be DEFLATE_MIN_SIZE (8), but using
* 8 will cause kernel crashes because of a bug in zlib.
*/
if (w_size < 9 || w_size > DEFLATE_MAX_SIZE)
return NULL;
#ifdef __osf__
state = (struct deflate_state *) ALLOC_SLEEP(sizeof(*state));
#else
state = (struct deflate_state *) ALLOC_NOSLEEP(sizeof(*state));
#endif
if (state == NULL)
return NULL;
state->strm.next_in = NULL;
state->strm.zalloc = (alloc_func) z_alloc_init;
state->strm.zfree = (free_func) z_free;
if (deflateInit2(&state->strm, Z_DEFAULT_COMPRESSION, DEFLATE_METHOD_VAL,
-w_size, 8, Z_DEFAULT_STRATEGY) != Z_OK) {
FREE(state, sizeof(*state));
return NULL;
}
state->strm.zalloc = (alloc_func) z_alloc;
state->w_size = w_size;
bzero(&state->stats, sizeof(state->stats));
return (void *) state;
}
static void
z_comp_free(arg)
void *arg;
{
struct deflate_state *state = (struct deflate_state *) arg;
deflateEnd(&state->strm);
FREE(state, sizeof(*state));
}
static int
z_comp_init(arg, options, opt_len, unit, hdrlen, debug)
void *arg;
u_char *options;
int opt_len, unit, hdrlen, debug;
{
struct deflate_state *state = (struct deflate_state *) arg;
if (opt_len < CILEN_DEFLATE
|| (options[0] != CI_DEFLATE && options[0] != CI_DEFLATE_DRAFT)
|| options[1] != CILEN_DEFLATE
|| DEFLATE_METHOD(options[2]) != DEFLATE_METHOD_VAL
|| DEFLATE_SIZE(options[2]) != state->w_size
|| options[3] != DEFLATE_CHK_SEQUENCE)
return 0;
state->seqno = 0;
state->unit = unit;
state->hdrlen = hdrlen;
state->debug = debug;
deflateReset(&state->strm);
return 1;
}
static void
z_comp_reset(arg)
void *arg;
{
struct deflate_state *state = (struct deflate_state *) arg;
state->seqno = 0;
deflateReset(&state->strm);
}
static int
z_compress(arg, mret, mp, orig_len, maxolen)
void *arg;
mblk_t **mret; /* compressed packet (out) */
mblk_t *mp; /* uncompressed packet (in) */
int orig_len, maxolen;
{
struct deflate_state *state = (struct deflate_state *) arg;
u_char *rptr, *wptr;
int proto, olen, wspace, r, flush;
mblk_t *m;
/*
* Check that the protocol is in the range we handle.
*/
*mret = NULL;
rptr = mp->b_rptr;
if (rptr + PPP_HDRLEN > mp->b_wptr) {
if (!pullupmsg(mp, PPP_HDRLEN))
return 0;
rptr = mp->b_rptr;
}
proto = PPP_PROTOCOL(rptr);
if (proto > 0x3fff || proto == 0xfd || proto == 0xfb)
return orig_len;
/* Allocate one mblk initially. */
if (maxolen > orig_len)
maxolen = orig_len;
if (maxolen <= PPP_HDRLEN + 2) {
wspace = 0;
m = NULL;
} else {
wspace = maxolen + state->hdrlen;
if (wspace > 4096)
wspace = 4096;
m = allocb(wspace, BPRI_MED);
}
if (m != NULL) {
*mret = m;
if (state->hdrlen + PPP_HDRLEN + 2 < wspace) {
m->b_rptr += state->hdrlen;
m->b_wptr = m->b_rptr;
wspace -= state->hdrlen;
}
wptr = m->b_wptr;
/*
* Copy over the PPP header and store the 2-byte sequence number.
*/
wptr[0] = PPP_ADDRESS(rptr);
wptr[1] = PPP_CONTROL(rptr);
wptr[2] = PPP_COMP >> 8;
wptr[3] = PPP_COMP;
wptr += PPP_HDRLEN;
wptr[0] = state->seqno >> 8;
wptr[1] = state->seqno;
wptr += 2;
state->strm.next_out = wptr;
state->strm.avail_out = wspace - (PPP_HDRLEN + 2);
} else {
state->strm.next_out = NULL;
state->strm.avail_out = 1000000;
}
++state->seqno;
rptr += (proto > 0xff)? 2: 3; /* skip 1st proto byte if 0 */
state->strm.next_in = rptr;
state->strm.avail_in = mp->b_wptr - rptr;
mp = mp->b_cont;
flush = (mp == NULL)? Z_PACKET_FLUSH: Z_NO_FLUSH;
olen = 0;
for (;;) {
r = deflate(&state->strm, flush);
if (r != Z_OK) {
printf("z_compress: deflate returned %d (%s)\n",
r, (state->strm.msg? state->strm.msg: ""));
break;
}
if (flush != Z_NO_FLUSH && state->strm.avail_out != 0)
break; /* all done */
if (state->strm.avail_in == 0 && mp != NULL) {
state->strm.next_in = mp->b_rptr;
state->strm.avail_in = mp->b_wptr - mp->b_rptr;
mp = mp->b_cont;
if (mp == NULL)
flush = Z_PACKET_FLUSH;
}
if (state->strm.avail_out == 0) {
if (m != NULL) {
m->b_wptr += wspace;
olen += wspace;
wspace = maxolen - olen;
if (wspace <= 0) {
wspace = 0;
m->b_cont = NULL;
} else {
if (wspace < 32)
wspace = 32;
else if (wspace > 4096)
wspace = 4096;
m->b_cont = allocb(wspace, BPRI_MED);
}
m = m->b_cont;
if (m != NULL) {
state->strm.next_out = m->b_wptr;
state->strm.avail_out = wspace;
}
}
if (m == NULL) {
state->strm.next_out = NULL;
state->strm.avail_out = 1000000;
}
}
}
if (m != NULL) {
m->b_wptr += wspace - state->strm.avail_out;
olen += wspace - state->strm.avail_out;
}
/*
* See if we managed to reduce the size of the packet.
*/
if (olen < orig_len && m != NULL) {
state->stats.comp_bytes += olen;
state->stats.comp_packets++;
} else {
if (*mret != NULL) {
freemsg(*mret);
*mret = NULL;
}
state->stats.inc_bytes += orig_len;
state->stats.inc_packets++;
olen = orig_len;
}
state->stats.unc_bytes += orig_len;
state->stats.unc_packets++;
return olen;
}
static void
z_comp_stats(arg, stats)
void *arg;
struct compstat *stats;
{
struct deflate_state *state = (struct deflate_state *) arg;
u_int out;
*stats = state->stats;
stats->ratio = stats->unc_bytes;
out = stats->comp_bytes + stats->unc_bytes;
if (stats->ratio <= 0x7ffffff)
stats->ratio <<= 8;
else
out >>= 8;
if (out != 0)
stats->ratio /= out;
}
/*
* Allocate space for a decompressor.
*/
static void *
z_decomp_alloc(options, opt_len)
u_char *options;
int opt_len;
{
struct deflate_state *state;
int w_size;
if (opt_len != CILEN_DEFLATE
|| (options[0] != CI_DEFLATE && options[0] != CI_DEFLATE_DRAFT)
|| options[1] != CILEN_DEFLATE
|| DEFLATE_METHOD(options[2]) != DEFLATE_METHOD_VAL
|| options[3] != DEFLATE_CHK_SEQUENCE)
return NULL;
w_size = DEFLATE_SIZE(options[2]);
/*
* N.B. the 9 below should be DEFLATE_MIN_SIZE (8), but using
* 8 will cause kernel crashes because of a bug in zlib.
*/
if (w_size < 9 || w_size > DEFLATE_MAX_SIZE)
return NULL;
#ifdef __osf__
state = (struct deflate_state *) ALLOC_SLEEP(sizeof(*state));
#else
state = (struct deflate_state *) ALLOC_NOSLEEP(sizeof(*state));
#endif
if (state == NULL)
return NULL;
state->strm.next_out = NULL;
state->strm.zalloc = (alloc_func) z_alloc_init;
state->strm.zfree = (free_func) z_free;
if (inflateInit2(&state->strm, -w_size) != Z_OK) {
FREE(state, sizeof(*state));
return NULL;
}
state->strm.zalloc = (alloc_func) z_alloc;
state->w_size = w_size;
bzero(&state->stats, sizeof(state->stats));
return (void *) state;
}
static void
z_decomp_free(arg)
void *arg;
{
struct deflate_state *state = (struct deflate_state *) arg;
inflateEnd(&state->strm);
FREE(state, sizeof(*state));
}
static int
z_decomp_init(arg, options, opt_len, unit, hdrlen, mru, debug)
void *arg;
u_char *options;
int opt_len, unit, hdrlen, mru, debug;
{
struct deflate_state *state = (struct deflate_state *) arg;
if (opt_len < CILEN_DEFLATE
|| (options[0] != CI_DEFLATE && options[0] != CI_DEFLATE_DRAFT)
|| options[1] != CILEN_DEFLATE
|| DEFLATE_METHOD(options[2]) != DEFLATE_METHOD_VAL
|| DEFLATE_SIZE(options[2]) != state->w_size
|| options[3] != DEFLATE_CHK_SEQUENCE)
return 0;
state->seqno = 0;
state->unit = unit;
state->hdrlen = hdrlen;
state->debug = debug;
state->mru = mru;
inflateReset(&state->strm);
return 1;
}
static void
z_decomp_reset(arg)
void *arg;
{
struct deflate_state *state = (struct deflate_state *) arg;
state->seqno = 0;
inflateReset(&state->strm);
}
/*
* Decompress a Deflate-compressed packet.
*
* Because of patent problems, we return DECOMP_ERROR for errors
* found by inspecting the input data and for system problems, but
* DECOMP_FATALERROR for any errors which could possibly be said to
* be being detected "after" decompression. For DECOMP_ERROR,
* we can issue a CCP reset-request; for DECOMP_FATALERROR, we may be
* infringing a patent of Motorola's if we do, so we take CCP down
* instead.
*
* Given that the frame has the correct sequence number and a good FCS,
* errors such as invalid codes in the input most likely indicate a
* bug, so we return DECOMP_FATALERROR for them in order to turn off
* compression, even though they are detected by inspecting the input.
*/
static int
z_decompress(arg, mi, mop)
void *arg;
mblk_t *mi, **mop;
{
struct deflate_state *state = (struct deflate_state *) arg;
mblk_t *mo, *mo_head;
u_char *rptr, *wptr;
int rlen, olen, ospace;
int seq, i, flush, r, decode_proto;
u_char hdr[PPP_HDRLEN + DEFLATE_OVHD];
*mop = NULL;
rptr = mi->b_rptr;
for (i = 0; i < PPP_HDRLEN + DEFLATE_OVHD; ++i) {
while (rptr >= mi->b_wptr) {
mi = mi->b_cont;
if (mi == NULL)
return DECOMP_ERROR;
rptr = mi->b_rptr;
}
hdr[i] = *rptr++;
}
/* Check the sequence number. */
seq = (hdr[PPP_HDRLEN] << 8) + hdr[PPP_HDRLEN+1];
if (seq != state->seqno) {
#if !DEFLATE_DEBUG
if (state->debug)
#endif
printf("z_decompress%d: bad seq # %d, expected %d\n",
state->unit, seq, state->seqno);
return DECOMP_ERROR;
}
++state->seqno;
/* Allocate an output message block. */
mo = allocb(DECOMP_CHUNK + state->hdrlen, BPRI_MED);
if (mo == NULL)
return DECOMP_ERROR;
mo_head = mo;
mo->b_cont = NULL;
mo->b_rptr += state->hdrlen;
mo->b_wptr = wptr = mo->b_rptr;
ospace = DECOMP_CHUNK;
olen = 0;
/*
* Fill in the first part of the PPP header. The protocol field
* comes from the decompressed data.
*/
wptr[0] = PPP_ADDRESS(hdr);
wptr[1] = PPP_CONTROL(hdr);
wptr[2] = 0;
/*
* Set up to call inflate. We set avail_out to 1 initially so we can
* look at the first byte of the output and decide whether we have
* a 1-byte or 2-byte protocol field.
*/
state->strm.next_in = rptr;
state->strm.avail_in = mi->b_wptr - rptr;
mi = mi->b_cont;
flush = (mi == NULL)? Z_PACKET_FLUSH: Z_NO_FLUSH;
rlen = state->strm.avail_in + PPP_HDRLEN + DEFLATE_OVHD;
state->strm.next_out = wptr + 3;
state->strm.avail_out = 1;
decode_proto = 1;
/*
* Call inflate, supplying more input or output as needed.
*/
for (;;) {
r = inflate(&state->strm, flush);
if (r != Z_OK) {
#if !DEFLATE_DEBUG
if (state->debug)
#endif
printf("z_decompress%d: inflate returned %d (%s)\n",
state->unit, r, (state->strm.msg? state->strm.msg: ""));
freemsg(mo_head);
return DECOMP_FATALERROR;
}
if (flush != Z_NO_FLUSH && state->strm.avail_out != 0)
break; /* all done */
if (state->strm.avail_in == 0 && mi != NULL) {
state->strm.next_in = mi->b_rptr;
state->strm.avail_in = mi->b_wptr - mi->b_rptr;
rlen += state->strm.avail_in;
mi = mi->b_cont;
if (mi == NULL)
flush = Z_PACKET_FLUSH;
}
if (state->strm.avail_out == 0) {
if (decode_proto) {
state->strm.avail_out = ospace - PPP_HDRLEN;
if ((wptr[3] & 1) == 0) {
/* 2-byte protocol field */
wptr[2] = wptr[3];
--state->strm.next_out;
++state->strm.avail_out;
}
decode_proto = 0;
} else {
mo->b_wptr += ospace;
olen += ospace;
mo->b_cont = allocb(DECOMP_CHUNK, BPRI_MED);
mo = mo->b_cont;
if (mo == NULL) {
freemsg(mo_head);
return DECOMP_ERROR;
}
state->strm.next_out = mo->b_rptr;
state->strm.avail_out = ospace = DECOMP_CHUNK;
}
}
}
if (decode_proto) {
freemsg(mo_head);
return DECOMP_ERROR;
}
mo->b_wptr += ospace - state->strm.avail_out;
olen += ospace - state->strm.avail_out;
#if DEFLATE_DEBUG
if (olen > state->mru + PPP_HDRLEN)
printf("ppp_deflate%d: exceeded mru (%d > %d)\n",
state->unit, olen, state->mru + PPP_HDRLEN);
#endif
state->stats.unc_bytes += olen;
state->stats.unc_packets++;
state->stats.comp_bytes += rlen;
state->stats.comp_packets++;
*mop = mo_head;
return DECOMP_OK;
}
/*
* Incompressible data has arrived - add it to the history.
*/
static void
z_incomp(arg, mi)
void *arg;
mblk_t *mi;
{
struct deflate_state *state = (struct deflate_state *) arg;
u_char *rptr;
int rlen, proto, r;
/*
* Check that the protocol is one we handle.
*/
rptr = mi->b_rptr;
if (rptr + PPP_HDRLEN > mi->b_wptr) {
if (!pullupmsg(mi, PPP_HDRLEN))
return;
rptr = mi->b_rptr;
}
proto = PPP_PROTOCOL(rptr);
if (proto > 0x3fff || proto == 0xfd || proto == 0xfb)
return;
++state->seqno;
/*
* Iterate through the message blocks, adding the characters in them
* to the decompressor's history. For the first block, we start
* at the either the 1st or 2nd byte of the protocol field,
* depending on whether the protocol value is compressible.
*/
rlen = mi->b_wptr - mi->b_rptr;
state->strm.next_in = rptr + 3;
state->strm.avail_in = rlen - 3;
if (proto > 0xff) {
--state->strm.next_in;
++state->strm.avail_in;
}
for (;;) {
r = inflateIncomp(&state->strm);
if (r != Z_OK) {
/* gak! */
#if !DEFLATE_DEBUG
if (state->debug)
#endif
printf("z_incomp%d: inflateIncomp returned %d (%s)\n",
state->unit, r, (state->strm.msg? state->strm.msg: ""));
return;
}
mi = mi->b_cont;
if (mi == NULL)
break;
state->strm.next_in = mi->b_rptr;
state->strm.avail_in = mi->b_wptr - mi->b_rptr;
rlen += state->strm.avail_in;
}
/*
* Update stats.
*/
state->stats.inc_bytes += rlen;
state->stats.inc_packets++;
state->stats.unc_bytes += rlen;
state->stats.unc_packets++;
}
#endif /* DO_DEFLATE */