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 */ 29 30 #include <sys/types.h> 31 #include <sys/systm.h> 32 #include <opencrypto/gfmult.h> 33 #include <opencrypto/gmac.h> 34 35 void 36 AES_GMAC_Init(void *ctx) 37 { 38 struct aes_gmac_ctx *agc; 39 40 agc = ctx; 41 bzero(agc, sizeof *agc); 42 } 43 44 void 45 AES_GMAC_Setkey(void *ctx, const uint8_t *key, u_int klen) 46 { 47 struct aes_gmac_ctx *agc; 48 const uint8_t zeros[GMAC_BLOCK_LEN] = {}; 49 struct gf128 h; 50 uint8_t hbuf[GMAC_BLOCK_LEN]; 51 52 agc = ctx; 53 agc->rounds = rijndaelKeySetupEnc(agc->keysched, key, klen * 8); 54 55 rijndaelEncrypt(agc->keysched, agc->rounds, zeros, hbuf); 56 57 h = gf128_read(hbuf); 58 gf128_genmultable4(h, &agc->ghashtbl); 59 60 explicit_bzero(&h, sizeof h); 61 explicit_bzero(hbuf, sizeof hbuf); 62 } 63 64 void 65 AES_GMAC_Reinit(void *ctx, const uint8_t *iv, u_int ivlen) 66 { 67 struct aes_gmac_ctx *agc; 68 69 agc = ctx; 70 KASSERT(ivlen <= sizeof agc->counter, ("passed ivlen too large!")); 71 memset(agc->counter, 0, sizeof(agc->counter)); 72 bcopy(iv, agc->counter, ivlen); 73 agc->counter[GMAC_BLOCK_LEN - 1] = 1; 74 75 memset(&agc->hash, 0, sizeof(agc->hash)); 76 } 77 78 int 79 AES_GMAC_Update(void *ctx, const void *vdata, u_int len) 80 { 81 struct aes_gmac_ctx *agc; 82 const uint8_t *data; 83 struct gf128 v; 84 uint8_t buf[GMAC_BLOCK_LEN] = {}; 85 int i; 86 87 agc = ctx; 88 data = vdata; 89 v = agc->hash; 90 91 while (len > 0) { 92 if (len >= 4*GMAC_BLOCK_LEN) { 93 i = 4*GMAC_BLOCK_LEN; 94 v = gf128_mul4b(v, data, &agc->ghashtbl); 95 } else if (len >= GMAC_BLOCK_LEN) { 96 i = GMAC_BLOCK_LEN; 97 v = gf128_add(v, gf128_read(data)); 98 v = gf128_mul(v, &agc->ghashtbl.tbls[0]); 99 } else { 100 i = len; 101 bcopy(data, buf, i); 102 v = gf128_add(v, gf128_read(&buf[0])); 103 v = gf128_mul(v, &agc->ghashtbl.tbls[0]); 104 explicit_bzero(buf, sizeof buf); 105 } 106 len -= i; 107 data += i; 108 } 109 110 agc->hash = v; 111 explicit_bzero(&v, sizeof v); 112 113 return (0); 114 } 115 116 void 117 AES_GMAC_Final(uint8_t *digest, void *ctx) 118 { 119 struct aes_gmac_ctx *agc; 120 uint8_t enccntr[GMAC_BLOCK_LEN]; 121 struct gf128 a; 122 123 agc = ctx; 124 125 rijndaelEncrypt(agc->keysched, agc->rounds, agc->counter, enccntr); 126 a = gf128_add(agc->hash, gf128_read(enccntr)); 127 gf128_write(a, digest); 128 129 explicit_bzero(enccntr, sizeof enccntr); 130 } 131