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/* $OpenBSD: umac.c,v 1.17 2018/04/10 00:10:49 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 lisence 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 <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[8])
{
/* '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
* muliple-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 optimaized 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;
explicit_bzero(ctx, sizeof(*ctx) + ALLOC_BOUNDARY);
free(ctx);
}
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 ----------------------------------------------- */
/* ---------------------------------------------------------------------- */
/* ---------------------------------------------------------------------- */