sys/netinet6/ah_aesxcbcmac.c

   1 /*      $NetBSD: ah_aesxcbcmac.c,v 1.6 2009/03/18 17:06:52 cegger Exp $ */
   2 /*      $KAME: ah_aesxcbcmac.c,v 1.7 2004/06/02 05:53:14 itojun Exp $   */
   3
   4 /*
   5  * Copyright (C) 1995, 1996, 1997, 1998 and 2003 WIDE Project.
   6  * All rights reserved.
   7  *
   8  * Redistribution and use in source and binary forms, with or without
   9  * modification, are permitted provided that the following conditions
  10  * are met:
  11  * 1. Redistributions of source code must retain the above copyright
  12  *    notice, this list of conditions and the following disclaimer.
  13  * 2. Redistributions in binary form must reproduce the above copyright
  14  *    notice, this list of conditions and the following disclaimer in the
  15  *    documentation and/or other materials provided with the distribution.
  16  * 3. Neither the name of the project nor the names of its contributors
  17  *    may be used to endorse or promote products derived from this software
  18  *    without specific prior written permission.
  19  *
  20  * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
  21  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  23  * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
  24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  30  * SUCH DAMAGE.
  31  */
  32
  33 #include <sys/cdefs.h>
  34 __KERNEL_RCSID(0, "$NetBSD: ah_aesxcbcmac.c,v 1.6 2009/03/18 17:06:52 cegger Exp $");
  35
  36 #include <sys/param.h>
  37 #include <sys/systm.h>
  38 #include <sys/socket.h>
  39 #include <sys/queue.h>
  40 #include <sys/syslog.h>
  41 #include <sys/mbuf.h>
  42
  43 #include <net/if.h>
  44 #include <net/route.h>
  45
  46 #include <netinet/in.h>
  47
  48 #include <netinet6/ipsec.h>
  49 #include <netinet6/ah.h>
  50 #include <netinet6/ah_aesxcbcmac.h>
  51
  52 #include <netkey/key.h>
  53
  54 #include <crypto/rijndael/rijndael.h>
  55
  56 #include <net/net_osdep.h>
  57
  58 #define AES_BLOCKSIZE   16
  59
  60 typedef struct {
  61         u_int8_t        e[AES_BLOCKSIZE];
  62         u_int8_t        buf[AES_BLOCKSIZE];
  63         size_t          buflen;
  64         u_int32_t       r_k1s[(RIJNDAEL_MAXNR+1)*4];
  65         u_int32_t       r_k2s[(RIJNDAEL_MAXNR+1)*4];
  66         u_int32_t       r_k3s[(RIJNDAEL_MAXNR+1)*4];
  67         int             r_nr; /* key-length-dependent number of rounds */
  68         u_int8_t        k2[AES_BLOCKSIZE];
  69         u_int8_t        k3[AES_BLOCKSIZE];
  70 } aesxcbc_ctx;
  71
  72 int
  73 ah_aes_xcbc_mac_init(struct ah_algorithm_state *state, struct secasvar * sav)
  74 {
  75         u_int8_t k1seed[AES_BLOCKSIZE] = { 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1 };
  76         u_int8_t k2seed[AES_BLOCKSIZE] = { 2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2 };
  77         u_int8_t k3seed[AES_BLOCKSIZE] = { 3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3 };
  78         u_int32_t r_ks[(RIJNDAEL_MAXNR+1)*4];
  79         aesxcbc_ctx *ctx;
  80         u_int8_t k1[AES_BLOCKSIZE];
  81
  82         if (!state)
  83                 panic("ah_aes_xcbc_mac_init: what?");
  84
  85         state->sav = sav;
  86         state->foo = malloc(sizeof(aesxcbc_ctx), M_TEMP, M_NOWAIT|M_ZERO);
  87         if (!state->foo)
  88                 return ENOBUFS;
  89
  90         ctx = (aesxcbc_ctx *)state->foo;
  91
  92         if ((ctx->r_nr = rijndaelKeySetupEnc(r_ks,
  93             (char *)_KEYBUF(sav->key_auth), AES_BLOCKSIZE * 8)) == 0)
  94                 return -1;
  95         rijndaelEncrypt(r_ks, ctx->r_nr, k1seed, k1);
  96         rijndaelEncrypt(r_ks, ctx->r_nr, k2seed, ctx->k2);
  97         rijndaelEncrypt(r_ks, ctx->r_nr, k3seed, ctx->k3);
  98         if (rijndaelKeySetupEnc(ctx->r_k1s, k1, AES_BLOCKSIZE * 8) == 0)
  99                 return -1;
 100         if (rijndaelKeySetupEnc(ctx->r_k2s, ctx->k2, AES_BLOCKSIZE * 8) == 0)
 101                 return -1;
 102         if (rijndaelKeySetupEnc(ctx->r_k3s, ctx->k3, AES_BLOCKSIZE * 8) == 0)
 103                 return -1;
 104
 105         return 0;
 106 }
 107
 108 void
 109 ah_aes_xcbc_mac_loop(struct ah_algorithm_state *state, u_int8_t *addr,
 110         size_t len)
 111 {
 112         u_int8_t buf[AES_BLOCKSIZE];
 113         aesxcbc_ctx *ctx;
 114         u_int8_t *ep;
 115         int i;
 116
 117         if (!state || !state->foo)
 118                 panic("ah_aes_xcbc_mac_loop: what?");
 119
 120         ctx = (aesxcbc_ctx *)state->foo;
 121         ep = addr + len;
 122
 123         if (ctx->buflen == sizeof(ctx->buf)) {
 124                 for (i = 0; i < sizeof(ctx->e); i++)
 125                         ctx->buf[i] ^= ctx->e[i];
 126                 rijndaelEncrypt(ctx->r_k1s, ctx->r_nr, ctx->buf, ctx->e);
 127                 ctx->buflen = 0;
 128         }
 129         if (ctx->buflen + len < sizeof(ctx->buf)) {
 130                 memcpy(ctx->buf + ctx->buflen, addr, len);
 131                 ctx->buflen += len;
 132                 return;
 133         }
 134         if (ctx->buflen && ctx->buflen + len > sizeof(ctx->buf)) {
 135                 memcpy(ctx->buf + ctx->buflen, addr,
 136                     sizeof(ctx->buf) - ctx->buflen);
 137                 for (i = 0; i < sizeof(ctx->e); i++)
 138                         ctx->buf[i] ^= ctx->e[i];
 139                 rijndaelEncrypt(ctx->r_k1s, ctx->r_nr, ctx->buf, ctx->e);
 140                 addr += sizeof(ctx->buf) - ctx->buflen;
 141                 ctx->buflen = 0;
 142         }
 143         /* due to the special processing for M[n], "=" case is not included */
 144         while (addr + AES_BLOCKSIZE < ep) {
 145                 memcpy(buf, addr, AES_BLOCKSIZE);
 146                 for (i = 0; i < sizeof(buf); i++)
 147                         buf[i] ^= ctx->e[i];
 148                 rijndaelEncrypt(ctx->r_k1s, ctx->r_nr, buf, ctx->e);
 149                 addr += AES_BLOCKSIZE;
 150         }
 151         if (addr < ep) {
 152                 memcpy(ctx->buf + ctx->buflen, addr, ep - addr);
 153                 ctx->buflen += ep - addr;
 154         }
 155 }
 156
 157 void
 158 ah_aes_xcbc_mac_result(struct ah_algorithm_state *state, u_int8_t *addr,
 159         size_t l)
 160 {
 161         u_char digest[AES_BLOCKSIZE];
 162         aesxcbc_ctx *ctx;
 163         int i;
 164
 165         ctx = (aesxcbc_ctx *)state->foo;
 166
 167         if (ctx->buflen == sizeof(ctx->buf)) {
 168                 for (i = 0; i < sizeof(ctx->buf); i++) {
 169                         ctx->buf[i] ^= ctx->e[i];
 170                         ctx->buf[i] ^= ctx->k2[i];
 171                 }
 172                 rijndaelEncrypt(ctx->r_k1s, ctx->r_nr, ctx->buf, digest);
 173         } else {
 174                 for (i = ctx->buflen; i < sizeof(ctx->buf); i++)
 175                         ctx->buf[i] = (i == ctx->buflen) ? 0x80 : 0x00;
 176                 for (i = 0; i < sizeof(ctx->buf); i++) {
 177                         ctx->buf[i] ^= ctx->e[i];
 178                         ctx->buf[i] ^= ctx->k3[i];
 179                 }
 180                 rijndaelEncrypt(ctx->r_k1s, ctx->r_nr, ctx->buf, digest);
 181         }
 182
 183         memcpy(addr, digest, sizeof(digest) > l ? l : sizeof(digest));
 184
 185         free(state->foo, M_TEMP);
 186 }