bsd/netinet6/ipcomp_core.c

   1 /*      $KAME: ipcomp_core.c,v 1.10 2000/02/22 14:04:23 itojun Exp $    */
   2
   3 /*
   4  * Copyright (C) 1999 WIDE Project.
   5  * All rights reserved.
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer.
  12  * 2. Redistributions in binary form must reproduce the above copyright
  13  *    notice, this list of conditions and the following disclaimer in the
  14  *    documentation and/or other materials provided with the distribution.
  15  * 3. Neither the name of the project nor the names of its contributors
  16  *    may be used to endorse or promote products derived from this software
  17  *    without specific prior written permission.
  18  *
  19  * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
  20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
  23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  29  * SUCH DAMAGE.
  30  */
  31
  32 /*
  33  * RFC2393 IP payload compression protocol (IPComp).
  34  */
  35
  36 #define _IP_VHL
  37 #if (defined(__FreeBSD__) && __FreeBSD__ >= 3) || defined(__NetBSD__)
  38 #include "opt_inet.h"
  39 #endif
  40
  41 #include <sys/param.h>
  42 #include <sys/systm.h>
  43 #include <sys/malloc.h>
  44 #include <sys/mbuf.h>
  45 #include <sys/domain.h>
  46 #include <sys/protosw.h>
  47 #include <sys/socket.h>
  48 #include <sys/errno.h>
  49 #include <sys/time.h>
  50 #include <sys/kernel.h>
  51 #include <sys/syslog.h>
  52 #include <sys/queue.h>
  53
  54 #include <net/if.h>
  55 #include <net/route.h>
  56 #include <net/netisr.h>
  57 #include <net/zlib.h>
  58 #include <kern/cpu_number.h>
  59
  60 #include <netinet/in.h>
  61 #include <netinet/in_systm.h>
  62 #include <netinet/ip.h>
  63 #include <netinet6/ipcomp.h>
  64 #include <netinet6/ipsec.h>
  65
  66 #include <net/net_osdep.h>
  67
  68 static void *deflate_alloc __P((void *, u_int, u_int));
  69 static void deflate_free __P((void *, void *));
  70 static int deflate_common __P((struct mbuf *, struct mbuf *, size_t *, int));
  71 static int deflate_compress __P((struct mbuf *, struct mbuf *, size_t *));
  72 static int deflate_decompress __P((struct mbuf *, struct mbuf *, size_t *));
  73
  74 /*
  75  * We need to use default window size (2^15 = 32Kbytes as of writing) for
  76  * inbound case.  Otherwise we get interop problem.
  77  * Use negative value to avoid Adler32 checksum.  This is an undocumented
  78  * feature in zlib (see ipsec wg mailing list archive in January 2000).
  79  */
  80 static int deflate_policy = Z_DEFAULT_COMPRESSION;
  81 static int deflate_window_out = -12;
  82 static const int deflate_window_in = -1 * MAX_WBITS;    /* don't change it */
  83 static int deflate_memlevel = MAX_MEM_LEVEL;
  84
  85 struct ipcomp_algorithm ipcomp_algorithms[] = {
  86         { NULL, NULL, -1 },
  87         { NULL, NULL, -1 },
  88         { deflate_compress, deflate_decompress, 90 },
  89         { NULL, NULL, 90 },
  90 };
  91
  92 static void *
  93 deflate_alloc(aux, items, siz)
  94         void *aux;
  95         u_int items;
  96         u_int siz;
  97 {
  98         void *ptr;
  99         MALLOC(ptr, void *, items * siz, M_TEMP, M_NOWAIT);
 100         return ptr;
 101 }
 102
 103 static void
 104 deflate_free(aux, ptr)
 105         void *aux;
 106         void *ptr;
 107 {
 108         FREE(ptr, M_TEMP);
 109 }
 110
 111 static int
 112 deflate_common(m, md, lenp, mode)
 113         struct mbuf *m;
 114         struct mbuf *md;
 115         size_t *lenp;
 116         int mode;       /* 0: compress 1: decompress */
 117 {
 118         struct mbuf *mprev;
 119         struct mbuf *p;
 120         struct mbuf *n, *n0 = NULL, **np;
 121         z_stream zs;
 122         int error = 0;
 123         int zerror;
 124         size_t offset;
 125         int firsttime, final, flush;
 126
 127         for (mprev = m; mprev && mprev->m_next != md; mprev = mprev->m_next)
 128                 ;
 129         if (!mprev)
 130                 panic("md is not in m in deflate_common");
 131
 132         bzero(&zs, sizeof(zs));
 133         zs.zalloc = deflate_alloc;
 134         zs.zfree = deflate_free;
 135
 136         zerror = mode ? inflateInit2(&zs, deflate_window_in)
 137                       : deflateInit2(&zs, deflate_policy, Z_DEFLATED,
 138                                 deflate_window_out, deflate_memlevel,
 139                                 Z_DEFAULT_STRATEGY);
 140         if (zerror != Z_OK) {
 141                 error = ENOBUFS;
 142                 goto fail;
 143         }
 144
 145         n0 = n = NULL;
 146         np = &n0;
 147         offset = 0;
 148         firsttime = 1;
 149         final = 0;
 150         flush = Z_NO_FLUSH;
 151         zerror = 0;
 152         p = md;
 153         while (1) {
 154                 /*
 155                  * first time, we need to setup the buffer before calling
 156                  * compression function.
 157                  */
 158                 if (firsttime)
 159                         firsttime = 0;
 160                 else {
 161                         zerror = mode ? inflate(&zs, flush)
 162                                       : deflate(&zs, flush);
 163                 }
 164
 165                 /* get input buffer */
 166                 if (p && zs.avail_in == 0) {
 167                         zs.next_in = mtod(p, u_int8_t *);
 168                         zs.avail_in = p->m_len;
 169                         p = p->m_next;
 170                         if (!p) {
 171                                 final = 1;
 172                                 flush = Z_PARTIAL_FLUSH;
 173                         }
 174                 }
 175
 176                 /* get output buffer */
 177                 if (zs.next_out == NULL || zs.avail_out == 0) {
 178                         /* keep the reply buffer into our chain */
 179                         if (n) {
 180                                 n->m_len = zs.total_out - offset;
 181                                 offset = zs.total_out;
 182                                 *np = n;
 183                                 np = &n->m_next;
 184                         }
 185
 186                         /* get a fresh reply buffer */
 187                         MGET(n, M_DONTWAIT, MT_DATA);
 188                         if (n) {
 189                                 MCLGET(n, M_DONTWAIT);
 190                         }
 191                         if (!n) {
 192                                 error = ENOBUFS;
 193                                 goto fail;
 194                         }
 195                         n->m_len = 0;
 196                         n->m_len = M_TRAILINGSPACE(n);
 197                         n->m_next = NULL;
 198                         /*
 199                          * if this is the first reply buffer, reserve
 200                          * region for ipcomp header.
 201                          */
 202                         if (*np == NULL) {
 203                                 n->m_len -= sizeof(struct ipcomp);
 204                                 n->m_data += sizeof(struct ipcomp);
 205                         }
 206
 207                         zs.next_out = mtod(n, u_int8_t *);
 208                         zs.avail_out = n->m_len;
 209                 }
 210
 211                 if (zerror == Z_OK) {
 212                         /*
 213                          * to terminate deflate/inflate process, we need to
 214                          * call {in,de}flate() with different flushing methods.
 215                          *
 216                          * deflate() needs at least one Z_PARTIAL_FLUSH,
 217                          * then use Z_FINISH until we get to the end.
 218                          * (if we use Z_FLUSH without Z_PARTIAL_FLUSH, deflate()
 219                          * will assume contiguous single output buffer, and that
 220                          * is not what we want)
 221                          * inflate() does not care about flushing method, but
 222                          * needs output buffer until it gets to the end.
 223                          *
 224                          * the most outer loop will be terminated with
 225                          * Z_STREAM_END.
 226                          */
 227                         if (final == 1) {
 228                                 /* reached end of mbuf chain */
 229                                 if (mode == 0)
 230                                         final = 2;
 231                                 else
 232                                         final = 3;
 233                         } else if (final == 2) {
 234                                 /* terminate deflate case */
 235                                 flush = Z_FINISH;
 236                         } else if (final == 3) {
 237                                 /* terminate inflate case */
 238                                 ;
 239                         }
 240                 } else if (zerror == Z_STREAM_END)
 241                         break;
 242                 else {
 243                         ipseclog((LOG_ERR, "ipcomp_%scompress: %sflate: %s\n",
 244                                 mode ? "de" : "", mode ? "in" : "de",
 245                                 zs.msg ? zs.msg : "unknown error"));
 246                         error = EINVAL;
 247                         goto fail;
 248                 }
 249         }
 250         zerror = mode ? inflateEnd(&zs) : deflateEnd(&zs);
 251         if (zerror != Z_OK) {
 252                 ipseclog((LOG_ERR, "ipcomp_%scompress: %sflate: %s\n",
 253                         mode ? "de" : "", mode ? "in" : "de",
 254                         zs.msg ? zs.msg : "unknown error"));
 255                 error = EINVAL;
 256                 goto fail;
 257         }
 258         /* keep the final reply buffer into our chain */
 259         if (n) {
 260                 n->m_len = zs.total_out - offset;
 261                 offset = zs.total_out;
 262                 *np = n;
 263                 np = &n->m_next;
 264         }
 265
 266         /* switch the mbuf to the new one */
 267         mprev->m_next = n0;
 268         m_freem(md);
 269         *lenp = zs.total_out;
 270
 271         return 0;
 272
 273 fail:
 274         if (m)
 275                 m_freem(m);
 276         if (n0)
 277                 m_freem(n0);
 278         return error;
 279 }
 280
 281 static int
 282 deflate_compress(m, md, lenp)
 283         struct mbuf *m;
 284         struct mbuf *md;
 285         size_t *lenp;
 286 {
 287         if (!m)
 288                 panic("m == NULL in deflate_compress");
 289         if (!md)
 290                 panic("md == NULL in deflate_compress");
 291         if (!lenp)
 292                 panic("lenp == NULL in deflate_compress");
 293
 294         return deflate_common(m, md, lenp, 0);
 295 }
 296
 297 static int
 298 deflate_decompress(m, md, lenp)
 299         struct mbuf *m;
 300         struct mbuf *md;
 301         size_t *lenp;
 302 {
 303         if (!m)
 304                 panic("m == NULL in deflate_decompress");
 305         if (!md)
 306                 panic("md == NULL in deflate_decompress");
 307         if (!lenp)
 308                 panic("lenp == NULL in deflate_decompress");
 309
 310         return deflate_common(m, md, lenp, 1);
 311 }