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Diffstat (limited to 'umac.c')
| -rw-r--r-- | umac.c | 1283 |
1 files changed, 1283 insertions, 0 deletions
@@ -0,0 +1,1283 @@ +/* $OpenBSD: umac.c,v 1.23 2023/03/07 01:30:52 djm Exp $ */ +/* ----------------------------------------------------------------------- + * + * umac.c -- C Implementation UMAC Message Authentication + * + * Version 0.93b of rfc4418.txt -- 2006 July 18 + * + * For a full description of UMAC message authentication see the UMAC + * world-wide-web page at http://www.cs.ucdavis.edu/~rogaway/umac + * Please report bugs and suggestions to the UMAC webpage. + * + * Copyright (c) 1999-2006 Ted Krovetz + * + * Permission to use, copy, modify, and distribute this software and + * its documentation for any purpose and with or without fee, is hereby + * granted provided that the above copyright notice appears in all copies + * and in supporting documentation, and that the name of the copyright + * holder not be used in advertising or publicity pertaining to + * distribution of the software without specific, written prior permission. + * + * Comments should be directed to Ted Krovetz (tdk@acm.org) + * + * ---------------------------------------------------------------------- */ + + /* ////////////////////// IMPORTANT NOTES ///////////////////////////////// + * + * 1) This version does not work properly on messages larger than 16MB + * + * 2) If you set the switch to use SSE2, then all data must be 16-byte + * aligned + * + * 3) When calling the function umac(), it is assumed that msg is in + * a writable buffer of length divisible by 32 bytes. The message itself + * does not have to fill the entire buffer, but bytes beyond msg may be + * zeroed. + * + * 4) Three free AES implementations are supported by this implementation of + * UMAC. Paulo Barreto's version is in the public domain and can be found + * at http://www.esat.kuleuven.ac.be/~rijmen/rijndael/ (search for + * "Barreto"). The only two files needed are rijndael-alg-fst.c and + * rijndael-alg-fst.h. Brian Gladman's version is distributed with the GNU + * Public license at http://fp.gladman.plus.com/AES/index.htm. It + * includes a fast IA-32 assembly version. The OpenSSL crypo library is + * the third. + * + * 5) With FORCE_C_ONLY flags set to 0, incorrect results are sometimes + * produced under gcc with optimizations set -O3 or higher. Dunno why. + * + /////////////////////////////////////////////////////////////////////// */ + +/* ---------------------------------------------------------------------- */ +/* --- User Switches ---------------------------------------------------- */ +/* ---------------------------------------------------------------------- */ + +#ifndef UMAC_OUTPUT_LEN +#define UMAC_OUTPUT_LEN 8 /* Alowable: 4, 8, 12, 16 */ +#endif + +#if UMAC_OUTPUT_LEN != 4 && UMAC_OUTPUT_LEN != 8 && \ + UMAC_OUTPUT_LEN != 12 && UMAC_OUTPUT_LEN != 16 +# error UMAC_OUTPUT_LEN must be defined to 4, 8, 12 or 16 +#endif + +/* #define FORCE_C_ONLY 1 ANSI C and 64-bit integers req'd */ +/* #define AES_IMPLEMENTAION 1 1 = OpenSSL, 2 = Barreto, 3 = Gladman */ +/* #define SSE2 0 Is SSE2 is available? */ +/* #define RUN_TESTS 0 Run basic correctness/speed tests */ +/* #define UMAC_AE_SUPPORT 0 Enable authenticated encryption */ + +/* ---------------------------------------------------------------------- */ +/* -- Global Includes --------------------------------------------------- */ +/* ---------------------------------------------------------------------- */ + +#include "includes.h" +#include <sys/types.h> +#include <string.h> +#include <stdarg.h> +#include <stdio.h> +#include <stdlib.h> +#include <stddef.h> + +#include "xmalloc.h" +#include "umac.h" +#include "misc.h" + +/* ---------------------------------------------------------------------- */ +/* --- Primitive Data Types --- */ +/* ---------------------------------------------------------------------- */ + +/* The following assumptions may need change on your system */ +typedef u_int8_t UINT8; /* 1 byte */ +typedef u_int16_t UINT16; /* 2 byte */ +typedef u_int32_t UINT32; /* 4 byte */ +typedef u_int64_t UINT64; /* 8 bytes */ +typedef unsigned int UWORD; /* Register */ + +/* ---------------------------------------------------------------------- */ +/* --- Constants -------------------------------------------------------- */ +/* ---------------------------------------------------------------------- */ + +#define UMAC_KEY_LEN 16 /* UMAC takes 16 bytes of external key */ + +/* Message "words" are read from memory in an endian-specific manner. */ +/* For this implementation to behave correctly, __LITTLE_ENDIAN__ must */ +/* be set true if the host computer is little-endian. */ + +#if BYTE_ORDER == LITTLE_ENDIAN +#define __LITTLE_ENDIAN__ 1 +#else +#define __LITTLE_ENDIAN__ 0 +#endif + +/* ---------------------------------------------------------------------- */ +/* ---------------------------------------------------------------------- */ +/* ----- Architecture Specific ------------------------------------------ */ +/* ---------------------------------------------------------------------- */ +/* ---------------------------------------------------------------------- */ + + +/* ---------------------------------------------------------------------- */ +/* ---------------------------------------------------------------------- */ +/* ----- Primitive Routines --------------------------------------------- */ +/* ---------------------------------------------------------------------- */ +/* ---------------------------------------------------------------------- */ + + +/* ---------------------------------------------------------------------- */ +/* --- 32-bit by 32-bit to 64-bit Multiplication ------------------------ */ +/* ---------------------------------------------------------------------- */ + +#define MUL64(a,b) ((UINT64)((UINT64)(UINT32)(a) * (UINT64)(UINT32)(b))) + +/* ---------------------------------------------------------------------- */ +/* --- Endian Conversion --- Forcing assembly on some platforms */ +/* ---------------------------------------------------------------------- */ + +#if (__LITTLE_ENDIAN__) +#define LOAD_UINT32_REVERSED(p) get_u32(p) +#define STORE_UINT32_REVERSED(p,v) put_u32(p,v) +#else +#define LOAD_UINT32_REVERSED(p) get_u32_le(p) +#define STORE_UINT32_REVERSED(p,v) put_u32_le(p,v) +#endif + +#define LOAD_UINT32_LITTLE(p) (get_u32_le(p)) +#define STORE_UINT32_BIG(p,v) put_u32(p, v) + +/* ---------------------------------------------------------------------- */ +/* ---------------------------------------------------------------------- */ +/* ----- Begin KDF & PDF Section ---------------------------------------- */ +/* ---------------------------------------------------------------------- */ +/* ---------------------------------------------------------------------- */ + +/* UMAC uses AES with 16 byte block and key lengths */ +#define AES_BLOCK_LEN 16 + +/* OpenSSL's AES */ +#ifdef WITH_OPENSSL +#include "openbsd-compat/openssl-compat.h" +#ifndef USE_BUILTIN_RIJNDAEL +# include <openssl/aes.h> +#endif +typedef AES_KEY aes_int_key[1]; +#define aes_encryption(in,out,int_key) \ + AES_encrypt((u_char *)(in),(u_char *)(out),(AES_KEY *)int_key) +#define aes_key_setup(key,int_key) \ + AES_set_encrypt_key((const u_char *)(key),UMAC_KEY_LEN*8,int_key) +#else +#include "rijndael.h" +#define AES_ROUNDS ((UMAC_KEY_LEN / 4) + 6) +typedef UINT8 aes_int_key[AES_ROUNDS+1][4][4]; /* AES internal */ +#define aes_encryption(in,out,int_key) \ + rijndaelEncrypt((u32 *)(int_key), AES_ROUNDS, (u8 *)(in), (u8 *)(out)) +#define aes_key_setup(key,int_key) \ + rijndaelKeySetupEnc((u32 *)(int_key), (const unsigned char *)(key), \ + UMAC_KEY_LEN*8) +#endif + +/* The user-supplied UMAC key is stretched using AES in a counter + * mode to supply all random bits needed by UMAC. The kdf function takes + * an AES internal key representation 'key' and writes a stream of + * 'nbytes' bytes to the memory pointed at by 'bufp'. Each distinct + * 'ndx' causes a distinct byte stream. + */ +static void kdf(void *bufp, aes_int_key key, UINT8 ndx, int nbytes) +{ + UINT8 in_buf[AES_BLOCK_LEN] = {0}; + UINT8 out_buf[AES_BLOCK_LEN]; + UINT8 *dst_buf = (UINT8 *)bufp; + int i; + + /* Setup the initial value */ + in_buf[AES_BLOCK_LEN-9] = ndx; + in_buf[AES_BLOCK_LEN-1] = i = 1; + + while (nbytes >= AES_BLOCK_LEN) { + aes_encryption(in_buf, out_buf, key); + memcpy(dst_buf,out_buf,AES_BLOCK_LEN); + in_buf[AES_BLOCK_LEN-1] = ++i; + nbytes -= AES_BLOCK_LEN; + dst_buf += AES_BLOCK_LEN; + } + if (nbytes) { + aes_encryption(in_buf, out_buf, key); + memcpy(dst_buf,out_buf,nbytes); + } + explicit_bzero(in_buf, sizeof(in_buf)); + explicit_bzero(out_buf, sizeof(out_buf)); +} + +/* The final UHASH result is XOR'd with the output of a pseudorandom + * function. Here, we use AES to generate random output and + * xor the appropriate bytes depending on the last bits of nonce. + * This scheme is optimized for sequential, increasing big-endian nonces. + */ + +typedef struct { + UINT8 cache[AES_BLOCK_LEN]; /* Previous AES output is saved */ + UINT8 nonce[AES_BLOCK_LEN]; /* The AES input making above cache */ + aes_int_key prf_key; /* Expanded AES key for PDF */ +} pdf_ctx; + +static void pdf_init(pdf_ctx *pc, aes_int_key prf_key) +{ + UINT8 buf[UMAC_KEY_LEN]; + + kdf(buf, prf_key, 0, UMAC_KEY_LEN); + aes_key_setup(buf, pc->prf_key); + + /* Initialize pdf and cache */ + memset(pc->nonce, 0, sizeof(pc->nonce)); + aes_encryption(pc->nonce, pc->cache, pc->prf_key); + explicit_bzero(buf, sizeof(buf)); +} + +static void pdf_gen_xor(pdf_ctx *pc, const UINT8 nonce[8], + UINT8 buf[UMAC_OUTPUT_LEN]) +{ + /* 'ndx' indicates that we'll be using the 0th or 1st eight bytes + * of the AES output. If last time around we returned the ndx-1st + * element, then we may have the result in the cache already. + */ + +#if (UMAC_OUTPUT_LEN == 4) +#define LOW_BIT_MASK 3 +#elif (UMAC_OUTPUT_LEN == 8) +#define LOW_BIT_MASK 1 +#elif (UMAC_OUTPUT_LEN > 8) +#define LOW_BIT_MASK 0 +#endif + union { + UINT8 tmp_nonce_lo[4]; + UINT32 align; + } t; +#if LOW_BIT_MASK != 0 + int ndx = nonce[7] & LOW_BIT_MASK; +#endif + *(UINT32 *)t.tmp_nonce_lo = ((const UINT32 *)nonce)[1]; + t.tmp_nonce_lo[3] &= ~LOW_BIT_MASK; /* zero last bit */ + + if ( (((UINT32 *)t.tmp_nonce_lo)[0] != ((UINT32 *)pc->nonce)[1]) || + (((const UINT32 *)nonce)[0] != ((UINT32 *)pc->nonce)[0]) ) + { + ((UINT32 *)pc->nonce)[0] = ((const UINT32 *)nonce)[0]; + ((UINT32 *)pc->nonce)[1] = ((UINT32 *)t.tmp_nonce_lo)[0]; + aes_encryption(pc->nonce, pc->cache, pc->prf_key); + } + +#if (UMAC_OUTPUT_LEN == 4) + *((UINT32 *)buf) ^= ((UINT32 *)pc->cache)[ndx]; +#elif (UMAC_OUTPUT_LEN == 8) + *((UINT64 *)buf) ^= ((UINT64 *)pc->cache)[ndx]; +#elif (UMAC_OUTPUT_LEN == 12) + ((UINT64 *)buf)[0] ^= ((UINT64 *)pc->cache)[0]; + ((UINT32 *)buf)[2] ^= ((UINT32 *)pc->cache)[2]; +#elif (UMAC_OUTPUT_LEN == 16) + ((UINT64 *)buf)[0] ^= ((UINT64 *)pc->cache)[0]; + ((UINT64 *)buf)[1] ^= ((UINT64 *)pc->cache)[1]; +#endif +} + +/* ---------------------------------------------------------------------- */ +/* ---------------------------------------------------------------------- */ +/* ----- Begin NH Hash Section ------------------------------------------ */ +/* ---------------------------------------------------------------------- */ +/* ---------------------------------------------------------------------- */ + +/* The NH-based hash functions used in UMAC are described in the UMAC paper + * and specification, both of which can be found at the UMAC website. + * The interface to this implementation has two + * versions, one expects the entire message being hashed to be passed + * in a single buffer and returns the hash result immediately. The second + * allows the message to be passed in a sequence of buffers. In the + * multiple-buffer interface, the client calls the routine nh_update() as + * many times as necessary. When there is no more data to be fed to the + * hash, the client calls nh_final() which calculates the hash output. + * Before beginning another hash calculation the nh_reset() routine + * must be called. The single-buffer routine, nh(), is equivalent to + * the sequence of calls nh_update() and nh_final(); however it is + * optimized and should be preferred whenever the multiple-buffer interface + * is not necessary. When using either interface, it is the client's + * responsibility to pass no more than L1_KEY_LEN bytes per hash result. + * + * The routine nh_init() initializes the nh_ctx data structure and + * must be called once, before any other PDF routine. + */ + + /* The "nh_aux" routines do the actual NH hashing work. They + * expect buffers to be multiples of L1_PAD_BOUNDARY. These routines + * produce output for all STREAMS NH iterations in one call, + * allowing the parallel implementation of the streams. + */ + +#define STREAMS (UMAC_OUTPUT_LEN / 4) /* Number of times hash is applied */ +#define L1_KEY_LEN 1024 /* Internal key bytes */ +#define L1_KEY_SHIFT 16 /* Toeplitz key shift between streams */ +#define L1_PAD_BOUNDARY 32 /* pad message to boundary multiple */ +#define ALLOC_BOUNDARY 16 /* Keep buffers aligned to this */ +#define HASH_BUF_BYTES 64 /* nh_aux_hb buffer multiple */ + +typedef struct { + UINT8 nh_key [L1_KEY_LEN + L1_KEY_SHIFT * (STREAMS - 1)]; /* NH Key */ + UINT8 data [HASH_BUF_BYTES]; /* Incoming data buffer */ + int next_data_empty; /* Bookkeeping variable for data buffer. */ + int bytes_hashed; /* Bytes (out of L1_KEY_LEN) incorporated. */ + UINT64 state[STREAMS]; /* on-line state */ +} nh_ctx; + + +#if (UMAC_OUTPUT_LEN == 4) + +static void nh_aux(void *kp, const void *dp, void *hp, UINT32 dlen) +/* NH hashing primitive. Previous (partial) hash result is loaded and +* then stored via hp pointer. The length of the data pointed at by "dp", +* "dlen", is guaranteed to be divisible by L1_PAD_BOUNDARY (32). Key +* is expected to be endian compensated in memory at key setup. +*/ +{ + UINT64 h; + UWORD c = dlen / 32; + UINT32 *k = (UINT32 *)kp; + const UINT32 *d = (const UINT32 *)dp; + UINT32 d0,d1,d2,d3,d4,d5,d6,d7; + UINT32 k0,k1,k2,k3,k4,k5,k6,k7; + + h = *((UINT64 *)hp); + do { + d0 = LOAD_UINT32_LITTLE(d+0); d1 = LOAD_UINT32_LITTLE(d+1); + d2 = LOAD_UINT32_LITTLE(d+2); d3 = LOAD_UINT32_LITTLE(d+3); + d4 = LOAD_UINT32_LITTLE(d+4); d5 = LOAD_UINT32_LITTLE(d+5); + d6 = LOAD_UINT32_LITTLE(d+6); d7 = LOAD_UINT32_LITTLE(d+7); + k0 = *(k+0); k1 = *(k+1); k2 = *(k+2); k3 = *(k+3); + k4 = *(k+4); k5 = *(k+5); k6 = *(k+6); k7 = *(k+7); + h += MUL64((k0 + d0), (k4 + d4)); + h += MUL64((k1 + d1), (k5 + d5)); + h += MUL64((k2 + d2), (k6 + d6)); + h += MUL64((k3 + d3), (k7 + d7)); + + d += 8; + k += 8; + } while (--c); + *((UINT64 *)hp) = h; +} + +#elif (UMAC_OUTPUT_LEN == 8) + +static void nh_aux(void *kp, const void *dp, void *hp, UINT32 dlen) +/* Same as previous nh_aux, but two streams are handled in one pass, + * reading and writing 16 bytes of hash-state per call. + */ +{ + UINT64 h1,h2; + UWORD c = dlen / 32; + UINT32 *k = (UINT32 *)kp; + const UINT32 *d = (const UINT32 *)dp; + UINT32 d0,d1,d2,d3,d4,d5,d6,d7; + UINT32 k0,k1,k2,k3,k4,k5,k6,k7, + k8,k9,k10,k11; + + h1 = *((UINT64 *)hp); + h2 = *((UINT64 *)hp + 1); + k0 = *(k+0); k1 = *(k+1); k2 = *(k+2); k3 = *(k+3); + do { + d0 = LOAD_UINT32_LITTLE(d+0); d1 = LOAD_UINT32_LITTLE(d+1); + d2 = LOAD_UINT32_LITTLE(d+2); d3 = LOAD_UINT32_LITTLE(d+3); + d4 = LOAD_UINT32_LITTLE(d+4); d5 = LOAD_UINT32_LITTLE(d+5); + d6 = LOAD_UINT32_LITTLE(d+6); d7 = LOAD_UINT32_LITTLE(d+7); + k4 = *(k+4); k5 = *(k+5); k6 = *(k+6); k7 = *(k+7); + k8 = *(k+8); k9 = *(k+9); k10 = *(k+10); k11 = *(k+11); + + h1 += MUL64((k0 + d0), (k4 + d4)); + h2 += MUL64((k4 + d0), (k8 + d4)); + + h1 += MUL64((k1 + d1), (k5 + d5)); + h2 += MUL64((k5 + d1), (k9 + d5)); + + h1 += MUL64((k2 + d2), (k6 + d6)); + h2 += MUL64((k6 + d2), (k10 + d6)); + + h1 += MUL64((k3 + d3), (k7 + d7)); + h2 += MUL64((k7 + d3), (k11 + d7)); + + k0 = k8; k1 = k9; k2 = k10; k3 = k11; + + d += 8; + k += 8; + } while (--c); + ((UINT64 *)hp)[0] = h1; + ((UINT64 *)hp)[1] = h2; +} + +#elif (UMAC_OUTPUT_LEN == 12) + +static void nh_aux(void *kp, const void *dp, void *hp, UINT32 dlen) +/* Same as previous nh_aux, but two streams are handled in one pass, + * reading and writing 24 bytes of hash-state per call. +*/ +{ + UINT64 h1,h2,h3; + UWORD c = dlen / 32; + UINT32 *k = (UINT32 *)kp; + const UINT32 *d = (const UINT32 *)dp; + UINT32 d0,d1,d2,d3,d4,d5,d6,d7; + UINT32 k0,k1,k2,k3,k4,k5,k6,k7, + k8,k9,k10,k11,k12,k13,k14,k15; + + h1 = *((UINT64 *)hp); + h2 = *((UINT64 *)hp + 1); + h3 = *((UINT64 *)hp + 2); + k0 = *(k+0); k1 = *(k+1); k2 = *(k+2); k3 = *(k+3); + k4 = *(k+4); k5 = *(k+5); k6 = *(k+6); k7 = *(k+7); + do { + d0 = LOAD_UINT32_LITTLE(d+0); d1 = LOAD_UINT32_LITTLE(d+1); + d2 = LOAD_UINT32_LITTLE(d+2); d3 = LOAD_UINT32_LITTLE(d+3); + d4 = LOAD_UINT32_LITTLE(d+4); d5 = LOAD_UINT32_LITTLE(d+5); + d6 = LOAD_UINT32_LITTLE(d+6); d7 = LOAD_UINT32_LITTLE(d+7); + k8 = *(k+8); k9 = *(k+9); k10 = *(k+10); k11 = *(k+11); + k12 = *(k+12); k13 = *(k+13); k14 = *(k+14); k15 = *(k+15); + + h1 += MUL64((k0 + d0), (k4 + d4)); + h2 += MUL64((k4 + d0), (k8 + d4)); + h3 += MUL64((k8 + d0), (k12 + d4)); + + h1 += MUL64((k1 + d1), (k5 + d5)); + h2 += MUL64((k5 + d1), (k9 + d5)); + h3 += MUL64((k9 + d1), (k13 + d5)); + + h1 += MUL64((k2 + d2), (k6 + d6)); + h2 += MUL64((k6 + d2), (k10 + d6)); + h3 += MUL64((k10 + d2), (k14 + d6)); + + h1 += MUL64((k3 + d3), (k7 + d7)); + h2 += MUL64((k7 + d3), (k11 + d7)); + h3 += MUL64((k11 + d3), (k15 + d7)); + + k0 = k8; k1 = k9; k2 = k10; k3 = k11; + k4 = k12; k5 = k13; k6 = k14; k7 = k15; + + d += 8; + k += 8; + } while (--c); + ((UINT64 *)hp)[0] = h1; + ((UINT64 *)hp)[1] = h2; + ((UINT64 *)hp)[2] = h3; +} + +#elif (UMAC_OUTPUT_LEN == 16) + +static void nh_aux(void *kp, const void *dp, void *hp, UINT32 dlen) +/* Same as previous nh_aux, but two streams are handled in one pass, + * reading and writing 24 bytes of hash-state per call. +*/ +{ + UINT64 h1,h2,h3,h4; + UWORD c = dlen / 32; + UINT32 *k = (UINT32 *)kp; + const UINT32 *d = (const UINT32 *)dp; + UINT32 d0,d1,d2,d3,d4,d5,d6,d7; + UINT32 k0,k1,k2,k3,k4,k5,k6,k7, + k8,k9,k10,k11,k12,k13,k14,k15, + k16,k17,k18,k19; + + h1 = *((UINT64 *)hp); + h2 = *((UINT64 *)hp + 1); + h3 = *((UINT64 *)hp + 2); + h4 = *((UINT64 *)hp + 3); + k0 = *(k+0); k1 = *(k+1); k2 = *(k+2); k3 = *(k+3); + k4 = *(k+4); k5 = *(k+5); k6 = *(k+6); k7 = *(k+7); + do { + d0 = LOAD_UINT32_LITTLE(d+0); d1 = LOAD_UINT32_LITTLE(d+1); + d2 = LOAD_UINT32_LITTLE(d+2); d3 = LOAD_UINT32_LITTLE(d+3); + d4 = LOAD_UINT32_LITTLE(d+4); d5 = LOAD_UINT32_LITTLE(d+5); + d6 = LOAD_UINT32_LITTLE(d+6); d7 = LOAD_UINT32_LITTLE(d+7); + k8 = *(k+8); k9 = *(k+9); k10 = *(k+10); k11 = *(k+11); + k12 = *(k+12); k13 = *(k+13); k14 = *(k+14); k15 = *(k+15); + k16 = *(k+16); k17 = *(k+17); k18 = *(k+18); k19 = *(k+19); + + h1 += MUL64((k0 + d0), (k4 + d4)); + h2 += MUL64((k4 + d0), (k8 + d4)); + h3 += MUL64((k8 + d0), (k12 + d4)); + h4 += MUL64((k12 + d0), (k16 + d4)); + + h1 += MUL64((k1 + d1), (k5 + d5)); + h2 += MUL64((k5 + d1), (k9 + d5)); + h3 += MUL64((k9 + d1), (k13 + d5)); + h4 += MUL64((k13 + d1), (k17 + d5)); + + h1 += MUL64((k2 + d2), (k6 + d6)); + h2 += MUL64((k6 + d2), (k10 + d6)); + h3 += MUL64((k10 + d2), (k14 + d6)); + h4 += MUL64((k14 + d2), (k18 + d6)); + + h1 += MUL64((k3 + d3), (k7 + d7)); + h2 += MUL64((k7 + d3), (k11 + d7)); + h3 += MUL64((k11 + d3), (k15 + d7)); + h4 += MUL64((k15 + d3), (k19 + d7)); + + k0 = k8; k1 = k9; k2 = k10; k3 = k11; + k4 = k12; k5 = k13; k6 = k14; k7 = k15; + k8 = k16; k9 = k17; k10 = k18; k11 = k19; + + d += 8; + k += 8; + } while (--c); + ((UINT64 *)hp)[0] = h1; + ((UINT64 *)hp)[1] = h2; + ((UINT64 *)hp)[2] = h3; + ((UINT64 *)hp)[3] = h4; +} + +/* ---------------------------------------------------------------------- */ +#endif /* UMAC_OUTPUT_LENGTH */ +/* ---------------------------------------------------------------------- */ + + +/* ---------------------------------------------------------------------- */ + +static void nh_transform(nh_ctx *hc, const UINT8 *buf, UINT32 nbytes) +/* This function is a wrapper for the primitive NH hash functions. It takes + * as argument "hc" the current hash context and a buffer which must be a + * multiple of L1_PAD_BOUNDARY. The key passed to nh_aux is offset + * appropriately according to how much message has been hashed already. + */ +{ + UINT8 *key; + + key = hc->nh_key + hc->bytes_hashed; + nh_aux(key, buf, hc->state, nbytes); +} + +/* ---------------------------------------------------------------------- */ + +#if (__LITTLE_ENDIAN__) +static void endian_convert(void *buf, UWORD bpw, UINT32 num_bytes) +/* We endian convert the keys on little-endian computers to */ +/* compensate for the lack of big-endian memory reads during hashing. */ +{ + UWORD iters = num_bytes / bpw; + if (bpw == 4) { + UINT32 *p = (UINT32 *)buf; + do { + *p = LOAD_UINT32_REVERSED(p); + p++; + } while (--iters); + } else if (bpw == 8) { + UINT32 *p = (UINT32 *)buf; + UINT32 t; + do { + t = LOAD_UINT32_REVERSED(p+1); + p[1] = LOAD_UINT32_REVERSED(p); + p[0] = t; + p += 2; + } while (--iters); + } +} +#define endian_convert_if_le(x,y,z) endian_convert((x),(y),(z)) +#else +#define endian_convert_if_le(x,y,z) do{}while(0) /* Do nothing */ +#endif + +/* ---------------------------------------------------------------------- */ + +static void nh_reset(nh_ctx *hc) +/* Reset nh_ctx to ready for hashing of new data */ +{ + hc->bytes_hashed = 0; + hc->next_data_empty = 0; + hc->state[0] = 0; +#if (UMAC_OUTPUT_LEN >= 8) + hc->state[1] = 0; +#endif +#if (UMAC_OUTPUT_LEN >= 12) + hc->state[2] = 0; +#endif +#if (UMAC_OUTPUT_LEN == 16) + hc->state[3] = 0; +#endif + +} + +/* ---------------------------------------------------------------------- */ + +static void nh_init(nh_ctx *hc, aes_int_key prf_key) +/* Generate nh_key, endian convert and reset to be ready for hashing. */ +{ + kdf(hc->nh_key, prf_key, 1, sizeof(hc->nh_key)); + endian_convert_if_le(hc->nh_key, 4, sizeof(hc->nh_key)); + nh_reset(hc); +} + +/* ---------------------------------------------------------------------- */ + +static void nh_update(nh_ctx *hc, const UINT8 *buf, UINT32 nbytes) +/* Incorporate nbytes of data into a nh_ctx, buffer whatever is not an */ +/* even multiple of HASH_BUF_BYTES. */ +{ + UINT32 i,j; + + j = hc->next_data_empty; + if ((j + nbytes) >= HASH_BUF_BYTES) { + if (j) { + i = HASH_BUF_BYTES - j; + memcpy(hc->data+j, buf, i); + nh_transform(hc,hc->data,HASH_BUF_BYTES); + nbytes -= i; + buf += i; + hc->bytes_hashed += HASH_BUF_BYTES; + } + if (nbytes >= HASH_BUF_BYTES) { + i = nbytes & ~(HASH_BUF_BYTES - 1); + nh_transform(hc, buf, i); + nbytes -= i; + buf += i; + hc->bytes_hashed += i; + } + j = 0; + } + memcpy(hc->data + j, buf, nbytes); + hc->next_data_empty = j + nbytes; +} + +/* ---------------------------------------------------------------------- */ + +static void zero_pad(UINT8 *p, int nbytes) +{ +/* Write "nbytes" of zeroes, beginning at "p" */ + if (nbytes >= (int)sizeof(UWORD)) { + while ((ptrdiff_t)p % sizeof(UWORD)) { + *p = 0; + nbytes--; + p++; + } + while (nbytes >= (int)sizeof(UWORD)) { + *(UWORD *)p = 0; + nbytes -= sizeof(UWORD); + p += sizeof(UWORD); + } + } + while (nbytes) { + *p = 0; + nbytes--; + p++; + } +} + +/* ---------------------------------------------------------------------- */ + +static void nh_final(nh_ctx *hc, UINT8 *result) +/* After passing some number of data buffers to nh_update() for integration + * into an NH context, nh_final is called to produce a hash result. If any + * bytes are in the buffer hc->data, incorporate them into the + * NH context. Finally, add into the NH accumulation "state" the total number + * of bits hashed. The resulting numbers are written to the buffer "result". + * If nh_update was never called, L1_PAD_BOUNDARY zeroes are incorporated. + */ +{ + int nh_len, nbits; + + if (hc->next_data_empty != 0) { + nh_len = ((hc->next_data_empty + (L1_PAD_BOUNDARY - 1)) & + ~(L1_PAD_BOUNDARY - 1)); + zero_pad(hc->data + hc->next_data_empty, + nh_len - hc->next_data_empty); + nh_transform(hc, hc->data, nh_len); + hc->bytes_hashed += hc->next_data_empty; + } else if (hc->bytes_hashed == 0) { + nh_len = L1_PAD_BOUNDARY; + zero_pad(hc->data, L1_PAD_BOUNDARY); + nh_transform(hc, hc->data, nh_len); + } + + nbits = (hc->bytes_hashed << 3); + ((UINT64 *)result)[0] = ((UINT64 *)hc->state)[0] + nbits; +#if (UMAC_OUTPUT_LEN >= 8) + ((UINT64 *)result)[1] = ((UINT64 *)hc->state)[1] + nbits; +#endif +#if (UMAC_OUTPUT_LEN >= 12) + ((UINT64 *)result)[2] = ((UINT64 *)hc->state)[2] + nbits; +#endif +#if (UMAC_OUTPUT_LEN == 16) + ((UINT64 *)result)[3] = ((UINT64 *)hc->state)[3] + nbits; +#endif + nh_reset(hc); +} + +/* ---------------------------------------------------------------------- */ + +static void nh(nh_ctx *hc, const UINT8 *buf, UINT32 padded_len, + UINT32 unpadded_len, UINT8 *result) +/* All-in-one nh_update() and nh_final() equivalent. + * Assumes that padded_len is divisible by L1_PAD_BOUNDARY and result is + * well aligned + */ +{ + UINT32 nbits; + + /* Initialize the hash state */ + nbits = (unpadded_len << 3); + + ((UINT64 *)result)[0] = nbits; +#if (UMAC_OUTPUT_LEN >= 8) + ((UINT64 *)result)[1] = nbits; +#endif +#if (UMAC_OUTPUT_LEN >= 12) + ((UINT64 *)result)[2] = nbits; +#endif +#if (UMAC_OUTPUT_LEN == 16) + ((UINT64 *)result)[3] = nbits; +#endif + + nh_aux(hc->nh_key, buf, result, padded_len); +} + +/* ---------------------------------------------------------------------- */ +/* ---------------------------------------------------------------------- */ +/* ----- Begin UHASH Section -------------------------------------------- */ +/* ---------------------------------------------------------------------- */ +/* ---------------------------------------------------------------------- */ + +/* UHASH is a multi-layered algorithm. Data presented to UHASH is first + * hashed by NH. The NH output is then hashed by a polynomial-hash layer + * unless the initial data to be hashed is short. After the polynomial- + * layer, an inner-product hash is used to produce the final UHASH output. + * + * UHASH provides two interfaces, one all-at-once and another where data + * buffers are presented sequentially. In the sequential interface, the + * UHASH client calls the routine uhash_update() as many times as necessary. + * When there is no more data to be fed to UHASH, the client calls + * uhash_final() which + * calculates the UHASH output. Before beginning another UHASH calculation + * the uhash_reset() routine must be called. The all-at-once UHASH routine, + * uhash(), is equivalent to the sequence of calls uhash_update() and + * uhash_final(); however it is optimized and should be + * used whenever the sequential interface is not necessary. + * + * The routine uhash_init() initializes the uhash_ctx data structure and + * must be called once, before any other UHASH routine. + */ + +/* ---------------------------------------------------------------------- */ +/* ----- Constants and uhash_ctx ---------------------------------------- */ +/* ---------------------------------------------------------------------- */ + +/* ---------------------------------------------------------------------- */ +/* ----- Poly hash and Inner-Product hash Constants --------------------- */ +/* ---------------------------------------------------------------------- */ + +/* Primes and masks */ +#define p36 ((UINT64)0x0000000FFFFFFFFBull) /* 2^36 - 5 */ +#define p64 ((UINT64)0xFFFFFFFFFFFFFFC5ull) /* 2^64 - 59 */ +#define m36 ((UINT64)0x0000000FFFFFFFFFull) /* The low 36 of 64 bits */ + + +/* ---------------------------------------------------------------------- */ + +typedef struct uhash_ctx { + nh_ctx hash; /* Hash context for L1 NH hash */ + UINT64 poly_key_8[STREAMS]; /* p64 poly keys */ + UINT64 poly_accum[STREAMS]; /* poly hash result */ + UINT64 ip_keys[STREAMS*4]; /* Inner-product keys */ + UINT32 ip_trans[STREAMS]; /* Inner-product translation */ + UINT32 msg_len; /* Total length of data passed */ + /* to uhash */ +} uhash_ctx; +typedef struct uhash_ctx *uhash_ctx_t; + +/* ---------------------------------------------------------------------- */ + + +/* The polynomial hashes use Horner's rule to evaluate a polynomial one + * word at a time. As described in the specification, poly32 and poly64 + * require keys from special domains. The following implementations exploit + * the special domains to avoid overflow. The results are not guaranteed to + * be within Z_p32 and Z_p64, but the Inner-Product hash implementation + * patches any errant values. + */ + +static UINT64 poly64(UINT64 cur, UINT64 key, UINT64 data) +{ + UINT32 key_hi = (UINT32)(key >> 32), + key_lo = (UINT32)key, + cur_hi = (UINT32)(cur >> 32), + cur_lo = (UINT32)cur, + x_lo, + x_hi; + UINT64 X,T,res; + + X = MUL64(key_hi, cur_lo) + MUL64(cur_hi, key_lo); + x_lo = (UINT32)X; + x_hi = (UINT32)(X >> 32); + + res = (MUL64(key_hi, cur_hi) + x_hi) * 59 + MUL64(key_lo, cur_lo); + + T = ((UINT64)x_lo << 32); + res += T; + if (res < T) + res += 59; + + res += data; + if (res < data) + res += 59; + + return res; +} + + +/* Although UMAC is specified to use a ramped polynomial hash scheme, this + * implementation does not handle all ramp levels. Because we don't handle + * the ramp up to p128 modulus in this implementation, we are limited to + * 2^14 poly_hash() invocations per stream (for a total capacity of 2^24 + * bytes input to UMAC per tag, ie. 16MB). + */ +static void poly_hash(uhash_ctx_t hc, UINT32 data_in[]) +{ + int i; + UINT64 *data=(UINT64*)data_in; + + for (i = 0; i < STREAMS; i++) { + if ((UINT32)(data[i] >> 32) == 0xfffffffful) { + hc->poly_accum[i] = poly64(hc->poly_accum[i], + hc->poly_key_8[i], p64 - 1); + hc->poly_accum[i] = poly64(hc->poly_accum[i], + hc->poly_key_8[i], (data[i] - 59)); + } else { + hc->poly_accum[i] = poly64(hc->poly_accum[i], + hc->poly_key_8[i], data[i]); + } + } +} + + +/* ---------------------------------------------------------------------- */ + + +/* The final step in UHASH is an inner-product hash. The poly hash + * produces a result not necessarily WORD_LEN bytes long. The inner- + * product hash breaks the polyhash output into 16-bit chunks and + * multiplies each with a 36 bit key. + */ + +static UINT64 ip_aux(UINT64 t, UINT64 *ipkp, UINT64 data) +{ + t = t + ipkp[0] * (UINT64)(UINT16)(data >> 48); + t = t + ipkp[1] * (UINT64)(UINT16)(data >> 32); + t = t + ipkp[2] * (UINT64)(UINT16)(data >> 16); + t = t + ipkp[3] * (UINT64)(UINT16)(data); + + return t; +} + +static UINT32 ip_reduce_p36(UINT64 t) +{ +/* Divisionless modular reduction */ + UINT64 ret; + + ret = (t & m36) + 5 * (t >> 36); + if (ret >= p36) + ret -= p36; + + /* return least significant 32 bits */ + return (UINT32)(ret); +} + + +/* If the data being hashed by UHASH is no longer than L1_KEY_LEN, then + * the polyhash stage is skipped and ip_short is applied directly to the + * NH output. + */ +static void ip_short(uhash_ctx_t ahc, UINT8 *nh_res, u_char *res) +{ + UINT64 t; + UINT64 *nhp = (UINT64 *)nh_res; + + t = ip_aux(0,ahc->ip_keys, nhp[0]); + STORE_UINT32_BIG((UINT32 *)res+0, ip_reduce_p36(t) ^ ahc->ip_trans[0]); +#if (UMAC_OUTPUT_LEN >= 8) + t = ip_aux(0,ahc->ip_keys+4, nhp[1]); + STORE_UINT32_BIG((UINT32 *)res+1, ip_reduce_p36(t) ^ ahc->ip_trans[1]); +#endif +#if (UMAC_OUTPUT_LEN >= 12) + t = ip_aux(0,ahc->ip_keys+8, nhp[2]); + STORE_UINT32_BIG((UINT32 *)res+2, ip_reduce_p36(t) ^ ahc->ip_trans[2]); +#endif +#if (UMAC_OUTPUT_LEN == 16) + t = ip_aux(0,ahc->ip_keys+12, nhp[3]); + STORE_UINT32_BIG((UINT32 *)res+3, ip_reduce_p36(t) ^ ahc->ip_trans[3]); +#endif +} + +/* If the data being hashed by UHASH is longer than L1_KEY_LEN, then + * the polyhash stage is not skipped and ip_long is applied to the + * polyhash output. + */ +static void ip_long(uhash_ctx_t ahc, u_char *res) +{ + int i; + UINT64 t; + + for (i = 0; i < STREAMS; i++) { + /* fix polyhash output not in Z_p64 */ + if (ahc->poly_accum[i] >= p64) + ahc->poly_accum[i] -= p64; + t = ip_aux(0,ahc->ip_keys+(i*4), ahc->poly_accum[i]); + STORE_UINT32_BIG((UINT32 *)res+i, + ip_reduce_p36(t) ^ ahc->ip_trans[i]); + } +} + + +/* ---------------------------------------------------------------------- */ + +/* ---------------------------------------------------------------------- */ + +/* Reset uhash context for next hash session */ +static int uhash_reset(uhash_ctx_t pc) +{ + nh_reset(&pc->hash); + pc->msg_len = 0; + pc->poly_accum[0] = 1; +#if (UMAC_OUTPUT_LEN >= 8) + pc->poly_accum[1] = 1; +#endif +#if (UMAC_OUTPUT_LEN >= 12) + pc->poly_accum[2] = 1; +#endif +#if (UMAC_OUTPUT_LEN == 16) + pc->poly_accum[3] = 1; +#endif + return 1; +} + +/* ---------------------------------------------------------------------- */ + +/* Given a pointer to the internal key needed by kdf() and a uhash context, + * initialize the NH context and generate keys needed for poly and inner- + * product hashing. All keys are endian adjusted in memory so that native + * loads cause correct keys to be in registers during calculation. + */ +static void uhash_init(uhash_ctx_t ahc, aes_int_key prf_key) +{ + int i; + UINT8 buf[(8*STREAMS+4)*sizeof(UINT64)]; + + /* Zero the entire uhash context */ + memset(ahc, 0, sizeof(uhash_ctx)); + + /* Initialize the L1 hash */ + nh_init(&ahc->hash, prf_key); + + /* Setup L2 hash variables */ + kdf(buf, prf_key, 2, sizeof(buf)); /* Fill buffer with index 1 key */ + for (i = 0; i < STREAMS; i++) { + /* Fill keys from the buffer, skipping bytes in the buffer not + * used by this implementation. Endian reverse the keys if on a + * little-endian computer. + */ + memcpy(ahc->poly_key_8+i, buf+24*i, 8); + endian_convert_if_le(ahc->poly_key_8+i, 8, 8); + /* Mask the 64-bit keys to their special domain */ + ahc->poly_key_8[i] &= ((UINT64)0x01ffffffu << 32) + 0x01ffffffu; + ahc->poly_accum[i] = 1; /* Our polyhash prepends a non-zero word */ + } + + /* Setup L3-1 hash variables */ + kdf(buf, prf_key, 3, sizeof(buf)); /* Fill buffer with index 2 key */ + for (i = 0; i < STREAMS; i++) + memcpy(ahc->ip_keys+4*i, buf+(8*i+4)*sizeof(UINT64), + 4*sizeof(UINT64)); + endian_convert_if_le(ahc->ip_keys, sizeof(UINT64), + sizeof(ahc->ip_keys)); + for (i = 0; i < STREAMS*4; i++) + ahc->ip_keys[i] %= p36; /* Bring into Z_p36 */ + + /* Setup L3-2 hash variables */ + /* Fill buffer with index 4 key */ + kdf(ahc->ip_trans, prf_key, 4, STREAMS * sizeof(UINT32)); + endian_convert_if_le(ahc->ip_trans, sizeof(UINT32), + STREAMS * sizeof(UINT32)); + explicit_bzero(buf, sizeof(buf)); +} + +/* ---------------------------------------------------------------------- */ + +#if 0 +static uhash_ctx_t uhash_alloc(u_char key[]) +{ +/* Allocate memory and force to a 16-byte boundary. */ + uhash_ctx_t ctx; + u_char bytes_to_add; + aes_int_key prf_key; + + ctx = (uhash_ctx_t)malloc(sizeof(uhash_ctx)+ALLOC_BOUNDARY); + if (ctx) { + if (ALLOC_BOUNDARY) { + bytes_to_add = ALLOC_BOUNDARY - + ((ptrdiff_t)ctx & (ALLOC_BOUNDARY -1)); + ctx = (uhash_ctx_t)((u_char *)ctx + bytes_to_add); + *((u_char *)ctx - 1) = bytes_to_add; + } + aes_key_setup(key,prf_key); + uhash_init(ctx, prf_key); + } + return (ctx); +} +#endif + +/* ---------------------------------------------------------------------- */ + +#if 0 +static int uhash_free(uhash_ctx_t ctx) +{ +/* Free memory allocated by uhash_alloc */ + u_char bytes_to_sub; + + if (ctx) { + if (ALLOC_BOUNDARY) { + bytes_to_sub = *((u_char *)ctx - 1); + ctx = (uhash_ctx_t)((u_char *)ctx - bytes_to_sub); + } + free(ctx); + } + return (1); +} +#endif +/* ---------------------------------------------------------------------- */ + +static int uhash_update(uhash_ctx_t ctx, const u_char *input, long len) +/* Given len bytes of data, we parse it into L1_KEY_LEN chunks and + * hash each one with NH, calling the polyhash on each NH output. + */ +{ + UWORD bytes_hashed, bytes_remaining; + UINT64 result_buf[STREAMS]; + UINT8 *nh_result = (UINT8 *)&result_buf; + + if (ctx->msg_len + len <= L1_KEY_LEN) { + nh_update(&ctx->hash, (const UINT8 *)input, len); + ctx->msg_len += len; + } else { + + bytes_hashed = ctx->msg_len % L1_KEY_LEN; + if (ctx->msg_len == L1_KEY_LEN) + bytes_hashed = L1_KEY_LEN; + + if (bytes_hashed + len >= L1_KEY_LEN) { + + /* If some bytes have been passed to the hash function */ + /* then we want to pass at most (L1_KEY_LEN - bytes_hashed) */ + /* bytes to complete the current nh_block. */ + if (bytes_hashed) { + bytes_remaining = (L1_KEY_LEN - bytes_hashed); + nh_update(&ctx->hash, (const UINT8 *)input, bytes_remaining); + nh_final(&ctx->hash, nh_result); + ctx->msg_len += bytes_remaining; + poly_hash(ctx,(UINT32 *)nh_result); + len -= bytes_remaining; + input += bytes_remaining; + } + + /* Hash directly from input stream if enough bytes */ + while (len >= L1_KEY_LEN) { + nh(&ctx->hash, (const UINT8 *)input, L1_KEY_LEN, + L1_KEY_LEN, nh_result); + ctx->msg_len += L1_KEY_LEN; + len -= L1_KEY_LEN; + input += L1_KEY_LEN; + poly_hash(ctx,(UINT32 *)nh_result); + } + } + + /* pass remaining < L1_KEY_LEN bytes of input data to NH */ + if (len) { + nh_update(&ctx->hash, (const UINT8 *)input, len); + ctx->msg_len += len; + } + } + + return (1); +} + +/* ---------------------------------------------------------------------- */ + +static int uhash_final(uhash_ctx_t ctx, u_char *res) +/* Incorporate any pending data, pad, and generate tag */ +{ + UINT64 result_buf[STREAMS]; + UINT8 *nh_result = (UINT8 *)&result_buf; + + if (ctx->msg_len > L1_KEY_LEN) { + if (ctx->msg_len % L1_KEY_LEN) { + nh_final(&ctx->hash, nh_result); + poly_hash(ctx,(UINT32 *)nh_result); + } + ip_long(ctx, res); + } else { + nh_final(&ctx->hash, nh_result); + ip_short(ctx,nh_result, res); + } + uhash_reset(ctx); + return (1); +} + +/* ---------------------------------------------------------------------- */ + +#if 0 +static int uhash(uhash_ctx_t ahc, u_char *msg, long len, u_char *res) +/* assumes that msg is in a writable buffer of length divisible by */ +/* L1_PAD_BOUNDARY. Bytes beyond msg[len] may be zeroed. */ +{ + UINT8 nh_result[STREAMS*sizeof(UINT64)]; + UINT32 nh_len; + int extra_zeroes_needed; + + /* If the message to be hashed is no longer than L1_HASH_LEN, we skip + * the polyhash. + */ + if (len <= L1_KEY_LEN) { + if (len == 0) /* If zero length messages will not */ + nh_len = L1_PAD_BOUNDARY; /* be seen, comment out this case */ + else + nh_len = ((len + (L1_PAD_BOUNDARY - 1)) & ~(L1_PAD_BOUNDARY - 1)); + extra_zeroes_needed = nh_len - len; + zero_pad((UINT8 *)msg + len, extra_zeroes_needed); + nh(&ahc->hash, (UINT8 *)msg, nh_len, len, nh_result); + ip_short(ahc,nh_result, res); + } else { + /* Otherwise, we hash each L1_KEY_LEN chunk with NH, passing the NH + * output to poly_hash(). + */ + do { + nh(&ahc->hash, (UINT8 *)msg, L1_KEY_LEN, L1_KEY_LEN, nh_result); + poly_hash(ahc,(UINT32 *)nh_result); + len -= L1_KEY_LEN; + msg += L1_KEY_LEN; + } while (len >= L1_KEY_LEN); + if (len) { + nh_len = ((len + (L1_PAD_BOUNDARY - 1)) & ~(L1_PAD_BOUNDARY - 1)); + extra_zeroes_needed = nh_len - len; + zero_pad((UINT8 *)msg + len, extra_zeroes_needed); + nh(&ahc->hash, (UINT8 *)msg, nh_len, len, nh_result); + poly_hash(ahc,(UINT32 *)nh_result); + } + + ip_long(ahc, res); + } + + uhash_reset(ahc); + return 1; +} +#endif + +/* ---------------------------------------------------------------------- */ +/* ---------------------------------------------------------------------- */ +/* ----- Begin UMAC Section --------------------------------------------- */ +/* ---------------------------------------------------------------------- */ +/* ---------------------------------------------------------------------- */ + +/* The UMAC interface has two interfaces, an all-at-once interface where + * the entire message to be authenticated is passed to UMAC in one buffer, + * and a sequential interface where the message is presented a little at a + * time. The all-at-once is more optimized than the sequential version and + * should be preferred when the sequential interface is not required. + */ +struct umac_ctx { + uhash_ctx hash; /* Hash function for message compression */ + pdf_ctx pdf; /* PDF for hashed output */ + void *free_ptr; /* Address to free this struct via */ +} umac_ctx; + +/* ---------------------------------------------------------------------- */ + +#if 0 +int umac_reset(struct umac_ctx *ctx) +/* Reset the hash function to begin a new authentication. */ +{ + uhash_reset(&ctx->hash); + return (1); +} +#endif + +/* ---------------------------------------------------------------------- */ + +int umac_delete(struct umac_ctx *ctx) +/* Deallocate the ctx structure */ +{ + if (ctx) { + if (ALLOC_BOUNDARY) + ctx = (struct umac_ctx *)ctx->free_ptr; + freezero(ctx, sizeof(*ctx) + ALLOC_BOUNDARY); + } + return (1); +} + +/* ---------------------------------------------------------------------- */ + +struct umac_ctx *umac_new(const u_char key[]) +/* Dynamically allocate a umac_ctx struct, initialize variables, + * generate subkeys from key. Align to 16-byte boundary. + */ +{ + struct umac_ctx *ctx, *octx; + size_t bytes_to_add; + aes_int_key prf_key; + + octx = ctx = xcalloc(1, sizeof(*ctx) + ALLOC_BOUNDARY); + if (ctx) { + if (ALLOC_BOUNDARY) { + bytes_to_add = ALLOC_BOUNDARY - + ((ptrdiff_t)ctx & (ALLOC_BOUNDARY - 1)); + ctx = (struct umac_ctx *)((u_char *)ctx + bytes_to_add); + } + ctx->free_ptr = octx; + aes_key_setup(key, prf_key); + pdf_init(&ctx->pdf, prf_key); + uhash_init(&ctx->hash, prf_key); + explicit_bzero(prf_key, sizeof(prf_key)); + } + + return (ctx); +} + +/* ---------------------------------------------------------------------- */ + +int umac_final(struct umac_ctx *ctx, u_char tag[], const u_char nonce[8]) +/* Incorporate any pending data, pad, and generate tag */ +{ + uhash_final(&ctx->hash, (u_char *)tag); + pdf_gen_xor(&ctx->pdf, (const UINT8 *)nonce, (UINT8 *)tag); + + return (1); +} + +/* ---------------------------------------------------------------------- */ + +int umac_update(struct umac_ctx *ctx, const u_char *input, long len) +/* Given len bytes of data, we parse it into L1_KEY_LEN chunks and */ +/* hash each one, calling the PDF on the hashed output whenever the hash- */ +/* output buffer is full. */ +{ + uhash_update(&ctx->hash, input, len); + return (1); +} + +/* ---------------------------------------------------------------------- */ + +#if 0 +int umac(struct umac_ctx *ctx, u_char *input, + long len, u_char tag[], + u_char nonce[8]) +/* All-in-one version simply calls umac_update() and umac_final(). */ +{ + uhash(&ctx->hash, input, len, (u_char *)tag); + pdf_gen_xor(&ctx->pdf, (UINT8 *)nonce, (UINT8 *)tag); + + return (1); +} +#endif + +/* ---------------------------------------------------------------------- */ +/* ---------------------------------------------------------------------- */ +/* ----- End UMAC Section ----------------------------------------------- */ +/* ---------------------------------------------------------------------- */ +/* ---------------------------------------------------------------------- */ |