+++ /dev/null
-/*
- * ==FILEVERSION 980319==
- *
- * 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 Linux kernel 1.3.X and later.
- *
- * 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.
- *
- * From: deflate.c,v 1.1 1996/01/18 03:17:48 paulus Exp
- */
-
-#include <linux/module.h>
-#include <linux/version.h>
-#include <linux/kernel.h>
-#include <linux/sched.h>
-#include <linux/types.h>
-#include <linux/fcntl.h>
-#include <linux/interrupt.h>
-#include <linux/ptrace.h>
-#include <linux/ioport.h>
-#include <linux/in.h>
-#include <linux/malloc.h>
-
-#undef VERSION
-/* a nice define to generate linux version numbers */
-#define VERSION(major,minor,patch) (((((major)<<8)+(minor))<<8)+(patch))
-
-#if LINUX_VERSION_CODE >= VERSION(2,1,4)
-#include <linux/vmalloc.h>
-#endif
-
-#include <linux/errno.h>
-#include <linux/sched.h> /* to get the struct task_struct */
-#include <linux/string.h> /* used in new tty drivers */
-#include <linux/signal.h> /* used in new tty drivers */
-
-#include <asm/system.h>
-
-#include <linux/netdevice.h>
-#include <linux/skbuff.h>
-#include <linux/inet.h>
-#include <linux/ioctl.h>
-
-#include <linux/ppp_defs.h>
-#include <linux/ppp-comp.h>
-
-#include "zlib.c"
-
-/*
- * State for a Deflate (de)compressor.
- */
-struct ppp_deflate_state {
- int seqno;
- int w_size;
- int unit;
- int mru;
- int debug;
- z_stream strm;
- struct compstat stats;
-};
-
-#define DEFLATE_OVHD 2 /* Deflate overhead/packet */
-
-static void *zalloc __P((void *, unsigned int items, unsigned int size));
-static void *zalloc_init __P((void *, unsigned int items,
- unsigned int size));
-static void zfree __P((void *, void *ptr));
-static void *z_comp_alloc __P((unsigned char *options, int opt_len));
-static void *z_decomp_alloc __P((unsigned char *options, int opt_len));
-static void z_comp_free __P((void *state));
-static void z_decomp_free __P((void *state));
-static int z_comp_init __P((void *state, unsigned char *options,
- int opt_len,
- int unit, int hdrlen, int debug));
-static int z_decomp_init __P((void *state, unsigned char *options,
- int opt_len,
- int unit, int hdrlen, int mru, int debug));
-static int z_compress __P((void *state, unsigned char *rptr,
- unsigned char *obuf,
- int isize, int osize));
-static void z_incomp __P((void *state, unsigned char *ibuf, int icnt));
-static int z_decompress __P((void *state, unsigned char *ibuf,
- int isize, unsigned char *obuf, int osize));
-static void z_comp_reset __P((void *state));
-static void z_decomp_reset __P((void *state));
-static void z_comp_stats __P((void *state, struct compstat *stats));
-
-struct chunk_header {
- int valloced; /* allocated with valloc, not kmalloc */
- int guard; /* check for overwritten header */
-};
-
-#define GUARD_MAGIC 0x77a8011a
-#define MIN_VMALLOC 2048 /* use kmalloc for blocks < this */
-
-/*
- * Space allocation and freeing routines for use by zlib routines.
- */
-void
-zfree(arg, ptr)
- void *arg;
- void *ptr;
-{
- struct chunk_header *hdr = ((struct chunk_header *)ptr) - 1;
-
- if (hdr->guard != GUARD_MAGIC) {
- printk(KERN_WARNING "zfree: header corrupted (%x %x) at %p\n",
- hdr->valloced, hdr->guard, hdr);
- return;
- }
- if (hdr->valloced)
- vfree(hdr);
- else
- kfree(hdr);
-}
-
-void *
-zalloc(arg, items, size)
- void *arg;
- unsigned int items, size;
-{
- struct chunk_header *hdr;
- unsigned nbytes;
-
- nbytes = items * size + sizeof(*hdr);
- hdr = kmalloc(nbytes, GFP_ATOMIC);
- if (hdr == 0)
- return 0;
- hdr->valloced = 0;
- hdr->guard = GUARD_MAGIC;
- return (void *) (hdr + 1);
-}
-
-void *
-zalloc_init(arg, items, size)
- void *arg;
- unsigned int items, size;
-{
- struct chunk_header *hdr;
- unsigned nbytes;
-
- nbytes = items * size + sizeof(*hdr);
- if (nbytes >= MIN_VMALLOC)
- hdr = vmalloc(nbytes);
- else
- hdr = kmalloc(nbytes, GFP_KERNEL);
- if (hdr == 0)
- return 0;
- hdr->valloced = nbytes >= MIN_VMALLOC;
- hdr->guard = GUARD_MAGIC;
- return (void *) (hdr + 1);
-}
-
-static void
-z_comp_free(arg)
- void *arg;
-{
- struct ppp_deflate_state *state = (struct ppp_deflate_state *) arg;
-
- if (state) {
- deflateEnd(&state->strm);
- kfree(state);
- MOD_DEC_USE_COUNT;
- }
-}
-
-/*
- * Allocate space for a compressor.
- */
-static void *
-z_comp_alloc(options, opt_len)
- unsigned char *options;
- int opt_len;
-{
- struct ppp_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]);
- if (w_size < DEFLATE_MIN_SIZE || w_size > DEFLATE_MAX_SIZE)
- return NULL;
-
- state = (struct ppp_deflate_state *) kmalloc(sizeof(*state), GFP_KERNEL);
- if (state == NULL)
- return NULL;
-
- MOD_INC_USE_COUNT;
- memset (state, 0, sizeof (struct ppp_deflate_state));
- state->strm.next_in = NULL;
- state->strm.zalloc = zalloc_init;
- state->strm.zfree = zfree;
- state->w_size = w_size;
-
- if (deflateInit2(&state->strm, Z_DEFAULT_COMPRESSION,
- DEFLATE_METHOD_VAL, -w_size, 8, Z_DEFAULT_STRATEGY)
- != Z_OK)
- goto out_free;
- state->strm.zalloc = zalloc;
- return (void *) state;
-
-out_free:
- z_comp_free(state);
- MOD_DEC_USE_COUNT;
- return NULL;
-}
-
-static int
-z_comp_init(arg, options, opt_len, unit, hdrlen, debug)
- void *arg;
- unsigned char *options;
- int opt_len, unit, hdrlen, debug;
-{
- struct ppp_deflate_state *state = (struct ppp_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->debug = debug;
-
- deflateReset(&state->strm);
-
- return 1;
-}
-
-static void
-z_comp_reset(arg)
- void *arg;
-{
- struct ppp_deflate_state *state = (struct ppp_deflate_state *) arg;
-
- state->seqno = 0;
- deflateReset(&state->strm);
-}
-
-int
-z_compress(arg, rptr, obuf, isize, osize)
- void *arg;
- unsigned char *rptr; /* uncompressed packet (in) */
- unsigned char *obuf; /* compressed packet (out) */
- int isize, osize;
-{
- struct ppp_deflate_state *state = (struct ppp_deflate_state *) arg;
- int r, proto, off, olen, oavail;
- unsigned char *wptr;
-
- /*
- * Check that the protocol is in the range we handle.
- */
- proto = PPP_PROTOCOL(rptr);
- if (proto > 0x3fff || proto == 0xfd || proto == 0xfb)
- return 0;
-
- /* Don't generate compressed packets which are larger than
- the uncompressed packet. */
- if (osize > isize)
- osize = isize;
-
- wptr = obuf;
-
- /*
- * 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 += DEFLATE_OVHD;
- olen = PPP_HDRLEN + DEFLATE_OVHD;
- state->strm.next_out = wptr;
- state->strm.avail_out = oavail = osize - olen;
- ++state->seqno;
-
- off = (proto > 0xff) ? 2 : 3; /* skip 1st proto byte if 0 */
- rptr += off;
- state->strm.next_in = rptr;
- state->strm.avail_in = (isize - off);
-
- for (;;) {
- r = deflate(&state->strm, Z_PACKET_FLUSH);
- if (r != Z_OK) {
- if (state->debug)
- printk(KERN_ERR
- "z_compress: deflate returned %d\n", r);
- break;
- }
- if (state->strm.avail_out == 0) {
- olen += oavail;
- state->strm.next_out = NULL;
- state->strm.avail_out = oavail = 1000000;
- } else {
- break; /* all done */
- }
- }
- olen += oavail - state->strm.avail_out;
-
- /*
- * See if we managed to reduce the size of the packet.
- */
- if (olen < isize) {
- state->stats.comp_bytes += olen;
- state->stats.comp_packets++;
- } else {
- state->stats.inc_bytes += isize;
- state->stats.inc_packets++;
- olen = 0;
- }
- state->stats.unc_bytes += isize;
- state->stats.unc_packets++;
-
- return olen;
-}
-
-static void
-z_comp_stats(arg, stats)
- void *arg;
- struct compstat *stats;
-{
- struct ppp_deflate_state *state = (struct ppp_deflate_state *) arg;
-
- *stats = state->stats;
-}
-
-static void
-z_decomp_free(arg)
- void *arg;
-{
- struct ppp_deflate_state *state = (struct ppp_deflate_state *) arg;
-
- if (state) {
- inflateEnd(&state->strm);
- kfree(state);
- MOD_DEC_USE_COUNT;
- }
-}
-
-/*
- * Allocate space for a decompressor.
- */
-static void *
-z_decomp_alloc(options, opt_len)
- unsigned char *options;
- int opt_len;
-{
- struct ppp_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]);
- if (w_size < DEFLATE_MIN_SIZE || w_size > DEFLATE_MAX_SIZE)
- return NULL;
-
- state = (struct ppp_deflate_state *) kmalloc(sizeof(*state), GFP_KERNEL);
- if (state == NULL)
- return NULL;
-
- MOD_INC_USE_COUNT;
- memset (state, 0, sizeof (struct ppp_deflate_state));
- state->w_size = w_size;
- state->strm.next_out = NULL;
- state->strm.zalloc = zalloc_init;
- state->strm.zfree = zfree;
-
- if (inflateInit2(&state->strm, -w_size) != Z_OK)
- goto out_free;
- state->strm.zalloc = zalloc;
- return (void *) state;
-
-out_free:
- z_decomp_free(state);
- MOD_DEC_USE_COUNT;
- return NULL;
-}
-
-static int
-z_decomp_init(arg, options, opt_len, unit, hdrlen, mru, debug)
- void *arg;
- unsigned char *options;
- int opt_len, unit, hdrlen, mru, debug;
-{
- struct ppp_deflate_state *state = (struct ppp_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->debug = debug;
- state->mru = mru;
-
- inflateReset(&state->strm);
-
- return 1;
-}
-
-static void
-z_decomp_reset(arg)
- void *arg;
-{
- struct ppp_deflate_state *state = (struct ppp_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.
- */
-int
-z_decompress(arg, ibuf, isize, obuf, osize)
- void *arg;
- unsigned char *ibuf;
- int isize;
- unsigned char *obuf;
- int osize;
-{
- struct ppp_deflate_state *state = (struct ppp_deflate_state *) arg;
- int olen, seq, r;
- int decode_proto, overflow;
- unsigned char overflow_buf[1];
-
- if (isize <= PPP_HDRLEN + DEFLATE_OVHD) {
- if (state->debug)
- printk(KERN_DEBUG "z_decompress%d: short pkt (%d)\n",
- state->unit, isize);
- return DECOMP_ERROR;
- }
-
- /* Check the sequence number. */
- seq = (ibuf[PPP_HDRLEN] << 8) + ibuf[PPP_HDRLEN+1];
- if (seq != state->seqno) {
- if (state->debug)
- printk(KERN_DEBUG "z_decompress%d: bad seq # %d, expected %d\n",
- state->unit, seq, state->seqno);
- return DECOMP_ERROR;
- }
- ++state->seqno;
-
- /*
- * Fill in the first part of the PPP header. The protocol field
- * comes from the decompressed data.
- */
- obuf[0] = PPP_ADDRESS(ibuf);
- obuf[1] = PPP_CONTROL(ibuf);
- obuf[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 = ibuf + PPP_HDRLEN + DEFLATE_OVHD;
- state->strm.avail_in = isize - (PPP_HDRLEN + DEFLATE_OVHD);
- state->strm.next_out = obuf + 3;
- state->strm.avail_out = 1;
- decode_proto = 1;
- overflow = 0;
-
- /*
- * Call inflate, supplying more input or output as needed.
- */
- for (;;) {
- r = inflate(&state->strm, Z_PACKET_FLUSH);
- if (r != Z_OK) {
- if (state->debug)
- printk(KERN_DEBUG "z_decompress%d: inflate returned %d (%s)\n",
- state->unit, r, (state->strm.msg? state->strm.msg: ""));
- return DECOMP_FATALERROR;
- }
- if (state->strm.avail_out != 0)
- break; /* all done */
- if (decode_proto) {
- state->strm.avail_out = osize - PPP_HDRLEN;
- if ((obuf[3] & 1) == 0) {
- /* 2-byte protocol field */
- obuf[2] = obuf[3];
- --state->strm.next_out;
- ++state->strm.avail_out;
- }
- decode_proto = 0;
- } else if (!overflow) {
- /*
- * We've filled up the output buffer; the only way to
- * find out whether inflate has any more characters
- * left is to give it another byte of output space.
- */
- state->strm.next_out = overflow_buf;
- state->strm.avail_out = 1;
- overflow = 1;
- } else {
- if (state->debug)
- printk(KERN_DEBUG "z_decompress%d: ran out of mru\n",
- state->unit);
- return DECOMP_FATALERROR;
- }
- }
-
- if (decode_proto) {
- if (state->debug)
- printk(KERN_DEBUG "z_decompress%d: didn't get proto\n",
- state->unit);
- return DECOMP_ERROR;
- }
-
- olen = osize + overflow - state->strm.avail_out;
- state->stats.unc_bytes += olen;
- state->stats.unc_packets++;
- state->stats.comp_bytes += isize;
- state->stats.comp_packets++;
-
- return olen;
-}
-
-/*
- * Incompressible data has arrived - add it to the history.
- */
-static void
-z_incomp(arg, ibuf, icnt)
- void *arg;
- unsigned char *ibuf;
- int icnt;
-{
- struct ppp_deflate_state *state = (struct ppp_deflate_state *) arg;
- int proto, r;
-
- /*
- * Check that the protocol is one we handle.
- */
- proto = PPP_PROTOCOL(ibuf);
- if (proto > 0x3fff || proto == 0xfd || proto == 0xfb)
- return;
-
- ++state->seqno;
-
- /*
- * We start at the either the 1st or 2nd byte of the protocol field,
- * depending on whether the protocol value is compressible.
- */
- state->strm.next_in = ibuf + 3;
- state->strm.avail_in = icnt - 3;
- if (proto > 0xff) {
- --state->strm.next_in;
- ++state->strm.avail_in;
- }
-
- r = inflateIncomp(&state->strm);
- if (r != Z_OK) {
- /* gak! */
- if (state->debug) {
- printk(KERN_DEBUG "z_incomp%d: inflateIncomp returned %d (%s)\n",
- state->unit, r, (state->strm.msg? state->strm.msg: ""));
- }
- return;
- }
-
- /*
- * Update stats.
- */
- state->stats.inc_bytes += icnt;
- state->stats.inc_packets++;
- state->stats.unc_bytes += icnt;
- state->stats.unc_packets++;
-}
-
-/*************************************************************
- * Module interface table
- *************************************************************/
-
-/* These are in ppp.c */
-extern int ppp_register_compressor (struct compressor *cp);
-extern void ppp_unregister_compressor (struct compressor *cp);
-
-/*
- * Procedures exported to if_ppp.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 */
-};
-
-#ifdef MODULE
-/*************************************************************
- * Module support routines
- *************************************************************/
-
-int
-init_module(void)
-{
- int answer = ppp_register_compressor (&ppp_deflate);
- if (answer == 0)
- printk (KERN_INFO
- "PPP Deflate Compression module registered\n");
- ppp_register_compressor(&ppp_deflate_draft);
- return answer;
-}
-
-void
-cleanup_module(void)
-{
- if (MOD_IN_USE)
- printk (KERN_INFO
- "Deflate Compression module busy, remove delayed\n");
- else {
- ppp_unregister_compressor (&ppp_deflate);
- ppp_unregister_compressor (&ppp_deflate_draft);
- }
-}
-#endif
projects / ppp.git / blobdiff