1 /*- 2 * Copyright (c) 2014 The FreeBSD Foundation 3 * 4 * This software was developed by John-Mark Gurney under 5 * the sponsorship of the FreeBSD Foundation and 6 * Rubicon Communications, LLC (Netgate). 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 * 16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 19 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26 * SUCH DAMAGE. 27 * 28 * $FreeBSD$ 29 * 30 */ 31 32 #include <sys/types.h> 33 #include <sys/systm.h> 34 #include <opencrypto/gfmult.h> 35 #include <opencrypto/gmac.h> 36 37 void 38 AES_GMAC_Init(void *ctx) 39 { 40 struct aes_gmac_ctx *agc; 41 42 agc = ctx; 43 bzero(agc, sizeof *agc); 44 } 45 46 void 47 AES_GMAC_Setkey(void *ctx, const uint8_t *key, u_int klen) 48 { 49 struct aes_gmac_ctx *agc; 50 const uint8_t zeros[GMAC_BLOCK_LEN] = {}; 51 struct gf128 h; 52 uint8_t hbuf[GMAC_BLOCK_LEN]; 53 54 agc = ctx; 55 agc->rounds = rijndaelKeySetupEnc(agc->keysched, key, klen * 8); 56 57 rijndaelEncrypt(agc->keysched, agc->rounds, zeros, hbuf); 58 59 h = gf128_read(hbuf); 60 gf128_genmultable4(h, &agc->ghashtbl); 61 62 explicit_bzero(&h, sizeof h); 63 explicit_bzero(hbuf, sizeof hbuf); 64 } 65 66 void 67 AES_GMAC_Reinit(void *ctx, const uint8_t *iv, u_int ivlen) 68 { 69 struct aes_gmac_ctx *agc; 70 71 agc = ctx; 72 KASSERT(ivlen <= sizeof agc->counter, ("passed ivlen too large!")); 73 memset(agc->counter, 0, sizeof(agc->counter)); 74 bcopy(iv, agc->counter, ivlen); 75 agc->counter[GMAC_BLOCK_LEN - 1] = 1; 76 77 memset(&agc->hash, 0, sizeof(agc->hash)); 78 } 79 80 int 81 AES_GMAC_Update(void *ctx, const void *vdata, u_int len) 82 { 83 struct aes_gmac_ctx *agc; 84 const uint8_t *data; 85 struct gf128 v; 86 uint8_t buf[GMAC_BLOCK_LEN] = {}; 87 int i; 88 89 agc = ctx; 90 data = vdata; 91 v = agc->hash; 92 93 while (len > 0) { 94 if (len >= 4*GMAC_BLOCK_LEN) { 95 i = 4*GMAC_BLOCK_LEN; 96 v = gf128_mul4b(v, data, &agc->ghashtbl); 97 } else if (len >= GMAC_BLOCK_LEN) { 98 i = GMAC_BLOCK_LEN; 99 v = gf128_add(v, gf128_read(data)); 100 v = gf128_mul(v, &agc->ghashtbl.tbls[0]); 101 } else { 102 i = len; 103 bcopy(data, buf, i); 104 v = gf128_add(v, gf128_read(&buf[0])); 105 v = gf128_mul(v, &agc->ghashtbl.tbls[0]); 106 explicit_bzero(buf, sizeof buf); 107 } 108 len -= i; 109 data += i; 110 } 111 112 agc->hash = v; 113 explicit_bzero(&v, sizeof v); 114 115 return (0); 116 } 117 118 void 119 AES_GMAC_Final(uint8_t *digest, void *ctx) 120 { 121 struct aes_gmac_ctx *agc; 122 uint8_t enccntr[GMAC_BLOCK_LEN]; 123 struct gf128 a; 124 125 agc = ctx; 126 127 rijndaelEncrypt(agc->keysched, agc->rounds, agc->counter, enccntr); 128 a = gf128_add(agc->hash, gf128_read(enccntr)); 129 gf128_write(a, digest); 130 131 explicit_bzero(enccntr, sizeof enccntr); 132 } 133