$NetBSD: patch-ar,v 1.1.1.1 1999/10/08 04:34:43 dbj Exp $ --- /dev/null Sat Sep 18 04:00:15 1999 +++ netbsd-1.4/ppp-deflate.c Sat Sep 18 04:06:29 1999 @@ -0,0 +1,680 @@ +/* NetBSD: ppp-deflate.c,v 1.6 1998/05/02 14:34:25 christos Exp */ +/* Id: ppp-deflate.c,v 1.5 1997/03/04 03:33:28 paulus Exp */ + +/* + * 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 mbufs on BSD-derived systems. + * + * 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 HAS 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. + */ + +#include +#include +#include +#include +#include +#include + +#define PACKETPTR struct mbuf * +#include + +#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 *zalloc __P((void *, u_int items, u_int size)); +static void zfree __P((void *, void *ptr)); +static void *z_comp_alloc __P((u_char *options, int opt_len)); +static void *z_decomp_alloc __P((u_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, u_char *options, int opt_len, + int unit, int hdrlen, int debug)); +static int z_decomp_init __P((void *state, u_char *options, int opt_len, + int unit, int hdrlen, int mru, int debug)); +static int z_compress __P((void *state, struct mbuf **mret, + struct mbuf *mp, int slen, int maxolen)); +static void z_incomp __P((void *state, struct mbuf *dmsg)); +static int z_decompress __P((void *state, struct mbuf *cmp, + struct mbuf **dmpp)); +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)); + +/* + * 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 */ +}; +/* + * Space allocation and freeing routines for use by zlib routines. + */ +void * +zalloc(notused, items, size) + void *notused; + u_int items, size; +{ + void *ptr; + + MALLOC(ptr, void *, items * size, M_DEVBUF, M_NOWAIT); + return ptr; +} + +void +zfree(notused, ptr) + void *notused; + void *ptr; +{ + FREE(ptr, M_DEVBUF); +} + +/* + * 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]); + if (w_size < DEFLATE_MIN_SIZE || w_size > DEFLATE_MAX_SIZE) + return NULL; + + MALLOC(state, struct deflate_state *, sizeof(struct deflate_state), + M_DEVBUF, M_NOWAIT); + if (state == NULL) + return NULL; + + state->strm.next_in = NULL; + state->strm.zalloc = zalloc; + state->strm.zfree = zfree; + if (deflateInit2(&state->strm, Z_DEFAULT_COMPRESSION, DEFLATE_METHOD_VAL, + -w_size, 8, Z_DEFAULT_STRATEGY) != Z_OK) { + FREE(state, M_DEVBUF); + return NULL; + } + + 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, M_DEVBUF); +} + +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); +} + +int +z_compress(arg, mret, mp, orig_len, maxolen) + void *arg; + struct mbuf **mret; /* compressed packet (out) */ + struct mbuf *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; + struct mbuf *m; + + /* + * Check that the protocol is in the range we handle. + */ + rptr = mtod(mp, u_char *); + proto = PPP_PROTOCOL(rptr); + if (proto > 0x3fff || proto == 0xfd || proto == 0xfb) { + *mret = NULL; + return orig_len; + } + + /* Allocate one mbuf initially. */ + if (maxolen > orig_len) + maxolen = orig_len; + MGET(m, M_DONTWAIT, MT_DATA); + *mret = m; + if (m != NULL) { + m->m_len = 0; + if (maxolen + state->hdrlen > MLEN) + MCLGET(m, M_DONTWAIT); + wspace = M_TRAILINGSPACE(m); + if (state->hdrlen + PPP_HDRLEN + 2 < wspace) { + m->m_data += state->hdrlen; + wspace -= state->hdrlen; + } + wptr = mtod(m, u_char *); + + /* + * 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; + wptr = NULL; + wspace = 0; + } + ++state->seqno; + + rptr += (proto > 0xff)? 2: 3; /* skip 1st proto byte if 0 */ + state->strm.next_in = rptr; + state->strm.avail_in = mtod(mp, u_char *) + mp->m_len - rptr; + mp = mp->m_next; + 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 = mtod(mp, u_char *); + state->strm.avail_in = mp->m_len; + mp = mp->m_next; + if (mp == NULL) + flush = Z_PACKET_FLUSH; + } + if (state->strm.avail_out == 0) { + if (m != NULL) { + m->m_len = wspace; + olen += wspace; + MGET(m->m_next, M_DONTWAIT, MT_DATA); + m = m->m_next; + if (m != NULL) { + m->m_len = 0; + if (maxolen - olen > MLEN) + MCLGET(m, M_DONTWAIT); + state->strm.next_out = mtod(m, u_char *); + state->strm.avail_out = wspace = M_TRAILINGSPACE(m); + } + } + if (m == NULL) { + state->strm.next_out = NULL; + state->strm.avail_out = 1000000; + } + } + } + if (m != NULL) + olen += (m->m_len = wspace - state->strm.avail_out); + + /* + * See if we managed to reduce the size of the packet. + */ + if (m != NULL && olen < orig_len) { + state->stats.comp_bytes += olen; + state->stats.comp_packets++; + } else { + if (*mret != NULL) { + m_freem(*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->inc_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]); + if (w_size < DEFLATE_MIN_SIZE || w_size > DEFLATE_MAX_SIZE) + return NULL; + + MALLOC(state, struct deflate_state *, sizeof(struct deflate_state), + M_DEVBUF, M_NOWAIT); + if (state == NULL) + return NULL; + + state->strm.next_out = NULL; + state->strm.zalloc = zalloc; + state->strm.zfree = zfree; + if (inflateInit2(&state->strm, -w_size) != Z_OK) { + FREE(state, M_DEVBUF); + return NULL; + } + + 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, M_DEVBUF); +} + +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. + */ +int +z_decompress(arg, mi, mop) + void *arg; + struct mbuf *mi, **mop; +{ + struct deflate_state *state = (struct deflate_state *) arg; + struct mbuf *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 = mtod(mi, u_char *); + rlen = mi->m_len; + for (i = 0; i < PPP_HDRLEN + DEFLATE_OVHD; ++i) { + while (rlen <= 0) { + mi = mi->m_next; + if (mi == NULL) + return DECOMP_ERROR; + rptr = mtod(mi, u_char *); + rlen = mi->m_len; + } + hdr[i] = *rptr++; + --rlen; + } + + /* Check the sequence number. */ + seq = (hdr[PPP_HDRLEN] << 8) + hdr[PPP_HDRLEN+1]; + if (seq != state->seqno) { + if (state->debug) + printf("z_decompress%d: bad seq # %d, expected %d\n", + state->unit, seq, state->seqno); + return DECOMP_ERROR; + } + ++state->seqno; + + /* Allocate an output mbuf. */ + MGETHDR(mo, M_DONTWAIT, MT_DATA); + if (mo == NULL) + return DECOMP_ERROR; + mo_head = mo; + mo->m_len = 0; + mo->m_next = NULL; + MCLGET(mo, M_DONTWAIT); + ospace = M_TRAILINGSPACE(mo); + if (state->hdrlen + PPP_HDRLEN < ospace) { + mo->m_data += state->hdrlen; + ospace -= state->hdrlen; + } + + /* + * Fill in the first part of the PPP header. The protocol field + * comes from the decompressed data. + */ + wptr = mtod(mo, u_char *); + 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 = rlen; + mi = mi->m_next; + flush = (mi == NULL)? Z_PACKET_FLUSH: Z_NO_FLUSH; + rlen += PPP_HDRLEN + DEFLATE_OVHD; + state->strm.next_out = wptr + 3; + state->strm.avail_out = 1; + decode_proto = 1; + olen = PPP_HDRLEN; + + /* + * 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: "")); + m_freem(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 = mtod(mi, u_char *); + state->strm.avail_in = mi->m_len; + rlen += mi->m_len; + mi = mi->m_next; + 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; + --olen; + } + decode_proto = 0; + } else { + mo->m_len = ospace; + olen += ospace; + MGET(mo->m_next, M_DONTWAIT, MT_DATA); + mo = mo->m_next; + if (mo == NULL) { + m_freem(mo_head); + return DECOMP_ERROR; + } + MCLGET(mo, M_DONTWAIT); + state->strm.next_out = mtod(mo, u_char *); + state->strm.avail_out = ospace = M_TRAILINGSPACE(mo); + } + } + } + if (decode_proto) { + m_freem(mo_head); + return DECOMP_ERROR; + } + olen += (mo->m_len = 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; + struct mbuf *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 = mtod(mi, u_char *); + proto = PPP_PROTOCOL(rptr); + if (proto > 0x3fff || proto == 0xfd || proto == 0xfb) + return; + + ++state->seqno; + + /* + * Iterate through the mbufs, adding the characters in them + * to the decompressor's history. For the first mbuf, we start + * at the either the 1st or 2nd byte of the protocol field, + * depending on whether the protocol value is compressible. + */ + rlen = mi->m_len; + 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->m_next; + if (mi == NULL) + break; + state->strm.next_in = mtod(mi, u_char *); + state->strm.avail_in = mi->m_len; + rlen += mi->m_len; + } + + /* + * Update stats. + */ + state->stats.inc_bytes += rlen; + state->stats.inc_packets++; + state->stats.unc_bytes += rlen; + state->stats.unc_packets++; +} + +#endif /* DO_DEFLATE */