1 /*- 2 * Copyright (c) 2014 The FreeBSD Foundation 3 * All rights reserved. 4 * 5 * This software was developed by John-Mark Gurney under 6 * the sponsorship of the FreeBSD Foundation and 7 * Rubicon Communications, LLC (Netgate). 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 * 17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27 * SUCH DAMAGE. 28 * 29 * $FreeBSD$ 30 * 31 */ 32 33 #include <sys/types.h> 34 #include <sys/systm.h> 35 #include <opencrypto/gfmult.h> 36 #include <opencrypto/gmac.h> 37 38 void 39 AES_GMAC_Init(struct aes_gmac_ctx *agc) 40 { 41 42 bzero(agc, sizeof *agc); 43 } 44 45 void 46 AES_GMAC_Setkey(struct aes_gmac_ctx *agc, const uint8_t *key, uint16_t klen) 47 { 48 const uint8_t zeros[GMAC_BLOCK_LEN] = {}; 49 struct gf128 h; 50 uint8_t hbuf[GMAC_BLOCK_LEN]; 51 52 agc->rounds = rijndaelKeySetupEnc(agc->keysched, key, klen * 8); 53 54 rijndaelEncrypt(agc->keysched, agc->rounds, zeros, hbuf); 55 56 h = gf128_read(hbuf); 57 gf128_genmultable4(h, &agc->ghashtbl); 58 59 explicit_bzero(&h, sizeof h); 60 explicit_bzero(hbuf, sizeof hbuf); 61 } 62 63 void 64 AES_GMAC_Reinit(struct aes_gmac_ctx *agc, const uint8_t *iv, uint16_t ivlen) 65 { 66 67 KASSERT(ivlen <= sizeof agc->counter, ("passed ivlen too large!")); 68 bcopy(iv, agc->counter, ivlen); 69 } 70 71 int 72 AES_GMAC_Update(struct aes_gmac_ctx *agc, const uint8_t *data, uint16_t len) 73 { 74 struct gf128 v; 75 uint8_t buf[GMAC_BLOCK_LEN] = {}; 76 int i; 77 78 v = agc->hash; 79 80 while (len > 0) { 81 if (len >= 4*GMAC_BLOCK_LEN) { 82 i = 4*GMAC_BLOCK_LEN; 83 v = gf128_mul4b(v, data, &agc->ghashtbl); 84 } else if (len >= GMAC_BLOCK_LEN) { 85 i = GMAC_BLOCK_LEN; 86 v = gf128_add(v, gf128_read(data)); 87 v = gf128_mul(v, &agc->ghashtbl.tbls[0]); 88 } else { 89 i = len; 90 bcopy(data, buf, i); 91 v = gf128_add(v, gf128_read(&buf[0])); 92 v = gf128_mul(v, &agc->ghashtbl.tbls[0]); 93 explicit_bzero(buf, sizeof buf); 94 } 95 len -= i; 96 data += i; 97 } 98 99 agc->hash = v; 100 explicit_bzero(&v, sizeof v); 101 102 return (0); 103 } 104 105 void 106 AES_GMAC_Final(uint8_t digest[GMAC_DIGEST_LEN], struct aes_gmac_ctx *agc) 107 { 108 uint8_t enccntr[GMAC_BLOCK_LEN]; 109 struct gf128 a; 110 111 /* XXX - zero additional bytes? */ 112 agc->counter[GMAC_BLOCK_LEN - 1] = 1; 113 114 rijndaelEncrypt(agc->keysched, agc->rounds, agc->counter, enccntr); 115 a = gf128_add(agc->hash, gf128_read(enccntr)); 116 gf128_write(a, digest); 117 118 explicit_bzero(enccntr, sizeof enccntr); 119 } 120