| 1 | /* $NetBSD: aesxcbcmac.c,v 1.2 2016/09/26 14:50:54 christos Exp $ */ |
| 2 | |
| 3 | /* |
| 4 | * Copyright (C) 1995, 1996, 1997, 1998 and 2003 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 | #include <sys/cdefs.h> |
| 33 | __KERNEL_RCSID(0, "$NetBSD: aesxcbcmac.c,v 1.2 2016/09/26 14:50:54 christos Exp $" ); |
| 34 | |
| 35 | #include <sys/param.h> |
| 36 | #include <sys/systm.h> |
| 37 | #include <crypto/rijndael/rijndael.h> |
| 38 | |
| 39 | #include <opencrypto/aesxcbcmac.h> |
| 40 | |
| 41 | int |
| 42 | aes_xcbc_mac_init(void *vctx, const uint8_t *key, u_int16_t keylen) |
| 43 | { |
| 44 | static const uint8_t k1seed[AES_BLOCKSIZE] = |
| 45 | { 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1 }; |
| 46 | static const uint8_t k2seed[AES_BLOCKSIZE] = |
| 47 | { 2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2 }; |
| 48 | static const uint8_t k3seed[AES_BLOCKSIZE] = |
| 49 | { 3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3 }; |
| 50 | u_int32_t r_ks[(RIJNDAEL_MAXNR+1)*4]; |
| 51 | aesxcbc_ctx *ctx; |
| 52 | uint8_t k1[AES_BLOCKSIZE]; |
| 53 | |
| 54 | ctx = vctx; |
| 55 | memset(ctx, 0, sizeof(*ctx)); |
| 56 | |
| 57 | if ((ctx->r_nr = rijndaelKeySetupEnc(r_ks, key, keylen * 8)) == 0) |
| 58 | return -1; |
| 59 | rijndaelEncrypt(r_ks, ctx->r_nr, k1seed, k1); |
| 60 | rijndaelEncrypt(r_ks, ctx->r_nr, k2seed, ctx->k2); |
| 61 | rijndaelEncrypt(r_ks, ctx->r_nr, k3seed, ctx->k3); |
| 62 | if (rijndaelKeySetupEnc(ctx->r_k1s, k1, AES_BLOCKSIZE * 8) == 0) |
| 63 | return -1; |
| 64 | if (rijndaelKeySetupEnc(ctx->r_k2s, ctx->k2, AES_BLOCKSIZE * 8) == 0) |
| 65 | return -1; |
| 66 | if (rijndaelKeySetupEnc(ctx->r_k3s, ctx->k3, AES_BLOCKSIZE * 8) == 0) |
| 67 | return -1; |
| 68 | |
| 69 | return 0; |
| 70 | } |
| 71 | |
| 72 | int |
| 73 | aes_xcbc_mac_loop(void *vctx, const uint8_t *addr, u_int16_t len) |
| 74 | { |
| 75 | uint8_t buf[AES_BLOCKSIZE]; |
| 76 | aesxcbc_ctx *ctx; |
| 77 | const uint8_t *ep; |
| 78 | int i; |
| 79 | |
| 80 | ctx = vctx; |
| 81 | ep = addr + len; |
| 82 | |
| 83 | if (ctx->buflen == sizeof(ctx->buf)) { |
| 84 | for (i = 0; i < sizeof(ctx->e); i++) |
| 85 | ctx->buf[i] ^= ctx->e[i]; |
| 86 | rijndaelEncrypt(ctx->r_k1s, ctx->r_nr, ctx->buf, ctx->e); |
| 87 | ctx->buflen = 0; |
| 88 | } |
| 89 | if (ctx->buflen + len < sizeof(ctx->buf)) { |
| 90 | memcpy(ctx->buf + ctx->buflen, addr, len); |
| 91 | ctx->buflen += len; |
| 92 | return 0; |
| 93 | } |
| 94 | if (ctx->buflen && ctx->buflen + len > sizeof(ctx->buf)) { |
| 95 | memcpy(ctx->buf + ctx->buflen, addr, |
| 96 | sizeof(ctx->buf) - ctx->buflen); |
| 97 | for (i = 0; i < sizeof(ctx->e); i++) |
| 98 | ctx->buf[i] ^= ctx->e[i]; |
| 99 | rijndaelEncrypt(ctx->r_k1s, ctx->r_nr, ctx->buf, ctx->e); |
| 100 | addr += sizeof(ctx->buf) - ctx->buflen; |
| 101 | ctx->buflen = 0; |
| 102 | } |
| 103 | /* due to the special processing for M[n], "=" case is not included */ |
| 104 | while (ep - addr > AES_BLOCKSIZE) { |
| 105 | memcpy(buf, addr, AES_BLOCKSIZE); |
| 106 | for (i = 0; i < sizeof(buf); i++) |
| 107 | buf[i] ^= ctx->e[i]; |
| 108 | rijndaelEncrypt(ctx->r_k1s, ctx->r_nr, buf, ctx->e); |
| 109 | addr += AES_BLOCKSIZE; |
| 110 | } |
| 111 | if (addr < ep) { |
| 112 | memcpy(ctx->buf + ctx->buflen, addr, ep - addr); |
| 113 | ctx->buflen += ep - addr; |
| 114 | } |
| 115 | return 0; |
| 116 | } |
| 117 | |
| 118 | void |
| 119 | aes_xcbc_mac_result(uint8_t *addr, void *vctx) |
| 120 | { |
| 121 | uint8_t digest[AES_BLOCKSIZE]; |
| 122 | aesxcbc_ctx *ctx; |
| 123 | int i; |
| 124 | |
| 125 | ctx = vctx; |
| 126 | |
| 127 | if (ctx->buflen == sizeof(ctx->buf)) { |
| 128 | for (i = 0; i < sizeof(ctx->buf); i++) { |
| 129 | ctx->buf[i] ^= ctx->e[i]; |
| 130 | ctx->buf[i] ^= ctx->k2[i]; |
| 131 | } |
| 132 | rijndaelEncrypt(ctx->r_k1s, ctx->r_nr, ctx->buf, digest); |
| 133 | } else { |
| 134 | for (i = ctx->buflen; i < sizeof(ctx->buf); i++) |
| 135 | ctx->buf[i] = (i == ctx->buflen) ? 0x80 : 0x00; |
| 136 | for (i = 0; i < sizeof(ctx->buf); i++) { |
| 137 | ctx->buf[i] ^= ctx->e[i]; |
| 138 | ctx->buf[i] ^= ctx->k3[i]; |
| 139 | } |
| 140 | rijndaelEncrypt(ctx->r_k1s, ctx->r_nr, ctx->buf, digest); |
| 141 | } |
| 142 | |
| 143 | memcpy(addr, digest, sizeof(digest)); |
| 144 | } |
| 145 | |