/* $OpenBSD: gcm128.c,v 1.13 2015/09/10 15:56:25 jsing Exp $ */

/* ====================================================================

 * Copyright (c) 2010 The OpenSSL Project.  All rights reserved.

 *

 * Redistribution and use in source and binary forms, with or without

 * modification, are permitted provided that the following conditions

 * are met:

 *

 * 1. Redistributions of source code must retain the above copyright

 *    notice, this list of conditions and the following disclaimer.

 *

 * 2. Redistributions in binary form must reproduce the above copyright

 *    notice, this list of conditions and the following disclaimer in

 *    the documentation and/or other materials provided with the

 *    distribution.

 *

 * 3. All advertising materials mentioning features or use of this

 *    software must display the following acknowledgment:

 *    "This product includes software developed by the OpenSSL Project

 *    for use in the OpenSSL Toolkit. (http://www.openssl.org/)"

 *

 * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to

 *    endorse or promote products derived from this software without

 *    prior written permission. For written permission, please contact

 *    openssl-core@openssl.org.

 *

 * 5. Products derived from this software may not be called "OpenSSL"

 *    nor may "OpenSSL" appear in their names without prior written

 *    permission of the OpenSSL Project.

 *

 * 6. Redistributions of any form whatsoever must retain the following

 *    acknowledgment:

 *    "This product includes software developed by the OpenSSL Project

 *    for use in the OpenSSL Toolkit (http://www.openssl.org/)"

 *

 * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY

 * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE

 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR

 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OpenSSL PROJECT OR

 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,

 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT

 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;

 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)

 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,

 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)

 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED

 * OF THE POSSIBILITY OF SUCH DAMAGE.

 * ====================================================================

 */

#define OPENSSL_FIPSAPI

#include <openssl/crypto.h>

#include "modes_lcl.h"

#include <string.h>

#ifndef MODES_DEBUG

# ifndef NDEBUG

#  define NDEBUG

# endif

#endif

#if defined(BSWAP4) && defined(__STRICT_ALIGNMENT)

/* redefine, because alignment is ensured */

#undef	GETU32

#define	GETU32(p)	BSWAP4(*(const u32 *)(p))

#undef	PUTU32

#define	PUTU32(p,v)	*(u32 *)(p) = BSWAP4(v)

#endif

#define	PACK(s)		((size_t)(s)<<(sizeof(size_t)*8-16))

#define REDUCE1BIT(V)	\

	do { \

		if (sizeof(size_t)==8) { \

			u64 T = U64(0xe100000000000000) & (0-(V.lo&1)); \

			V.lo  = (V.hi<<63)|(V.lo>>1); \

			V.hi  = (V.hi>>1 )^T; \

		} else { \

			u32 T = 0xe1000000U & (0-(u32)(V.lo&1)); \

			V.lo  = (V.hi<<63)|(V.lo>>1); \

			V.hi  = (V.hi>>1 )^((u64)T<<32); \

		} \

	} while(0)

/*

 * Even though permitted values for TABLE_BITS are 8, 4 and 1, it should

 * never be set to 8. 8 is effectively reserved for testing purposes.

 * TABLE_BITS>1 are lookup-table-driven implementations referred to as

 * "Shoup's" in GCM specification. In other words OpenSSL does not cover

 * whole spectrum of possible table driven implementations. Why? In

 * non-"Shoup's" case memory access pattern is segmented in such manner,

 * that it's trivial to see that cache timing information can reveal

 * fair portion of intermediate hash value. Given that ciphertext is

 * always available to attacker, it's possible for him to attempt to

 * deduce secret parameter H and if successful, tamper with messages

 * [which is nothing but trivial in CTR mode]. In "Shoup's" case it's

 * not as trivial, but there is no reason to believe that it's resistant

 * to cache-timing attack. And the thing about "8-bit" implementation is

 * that it consumes 16 (sixteen) times more memory, 4KB per individual

 * key + 1KB shared. Well, on pros side it should be twice as fast as

 * "4-bit" version. And for gcc-generated x86[_64] code, "8-bit" version

 * was observed to run ~75% faster, closer to 100% for commercial

 * compilers... Yet "4-bit" procedure is preferred, because it's

 * believed to provide better security-performance balance and adequate

 * all-round performance. "All-round" refers to things like:

 *

 * - shorter setup time effectively improves overall timing for

 *   handling short messages;

 * - larger table allocation can become unbearable because of VM

 *   subsystem penalties (for example on Windows large enough free

 *   results in VM working set trimming, meaning that consequent

 *   malloc would immediately incur working set expansion);

 * - larger table has larger cache footprint, which can affect

 *   performance of other code paths (not necessarily even from same

 *   thread in Hyper-Threading world);

 *

 * Value of 1 is not appropriate for performance reasons.

 */

#if	TABLE_BITS==8

static void gcm_init_8bit(u128 Htable[256], u64 H[2])

{

	int  i, j;

	u128 V;

	Htable[0].hi = 0;

	Htable[0].lo = 0;

	V.hi = H[0];

	V.lo = H[1];

	for (Htable[128]=V, i=64; i>0; i>>=1) {

		REDUCE1BIT(V);

		Htable[i] = V;

	}

	for (i=2; i<256; i<<=1) {

		u128 *Hi = Htable+i, H0 = *Hi;

		for (j=1; j<i; ++j) {

			Hi[j].hi = H0.hi^Htable[j].hi;

			Hi[j].lo = H0.lo^Htable[j].lo;

		}

	}

}

static void gcm_gmult_8bit(u64 Xi[2], const u128 Htable[256])

{

	u128 Z = { 0, 0};

	const u8 *xi = (const u8 *)Xi+15;

	size_t rem, n = *xi;

	static const size_t rem_8bit[256] = {

		PACK(0x0000), PACK(0x01C2), PACK(0x0384), PACK(0x0246),

		PACK(0x0708), PACK(0x06CA), PACK(0x048C), PACK(0x054E),

		PACK(0x0E10), PACK(0x0FD2), PACK(0x0D94), PACK(0x0C56),

		PACK(0x0918), PACK(0x08DA), PACK(0x0A9C), PACK(0x0B5E),

		PACK(0x1C20), PACK(0x1DE2), PACK(0x1FA4), PACK(0x1E66),

		PACK(0x1B28), PACK(0x1AEA), PACK(0x18AC), PACK(0x196E),

		PACK(0x1230), PACK(0x13F2), PACK(0x11B4), PACK(0x1076),

		PACK(0x1538), PACK(0x14FA), PACK(0x16BC), PACK(0x177E),

		PACK(0x3840), PACK(0x3982), PACK(0x3BC4), PACK(0x3A06),

		PACK(0x3F48), PACK(0x3E8A), PACK(0x3CCC), PACK(0x3D0E),

		PACK(0x3650), PACK(0x3792), PACK(0x35D4), PACK(0x3416),

		PACK(0x3158), PACK(0x309A), PACK(0x32DC), PACK(0x331E),

		PACK(0x2460), PACK(0x25A2), PACK(0x27E4), PACK(0x2626),

		PACK(0x2368), PACK(0x22AA), PACK(0x20EC), PACK(0x212E),

		PACK(0x2A70), PACK(0x2BB2), PACK(0x29F4), PACK(0x2836),

		PACK(0x2D78), PACK(0x2CBA), PACK(0x2EFC), PACK(0x2F3E),

		PACK(0x7080), PACK(0x7142), PACK(0x7304), PACK(0x72C6),

		PACK(0x7788), PACK(0x764A), PACK(0x740C), PACK(0x75CE),

		PACK(0x7E90), PACK(0x7F52), PACK(0x7D14), PACK(0x7CD6),

		PACK(0x7998), PACK(0x785A), PACK(0x7A1C), PACK(0x7BDE),

		PACK(0x6CA0), PACK(0x6D62), PACK(0x6F24), PACK(0x6EE6),

		PACK(0x6BA8), PACK(0x6A6A), PACK(0x682C), PACK(0x69EE),

		PACK(0x62B0), PACK(0x6372), PACK(0x6134), PACK(0x60F6),

		PACK(0x65B8), PACK(0x647A), PACK(0x663C), PACK(0x67FE),

		PACK(0x48C0), PACK(0x4902), PACK(0x4B44), PACK(0x4A86),

		PACK(0x4FC8), PACK(0x4E0A), PACK(0x4C4C), PACK(0x4D8E),

		PACK(0x46D0), PACK(0x4712), PACK(0x4554), PACK(0x4496),

		PACK(0x41D8), PACK(0x401A), PACK(0x425C), PACK(0x439E),

		PACK(0x54E0), PACK(0x5522), PACK(0x5764), PACK(0x56A6),

		PACK(0x53E8), PACK(0x522A), PACK(0x506C), PACK(0x51AE),

		PACK(0x5AF0), PACK(0x5B32), PACK(0x5974), PACK(0x58B6),

		PACK(0x5DF8), PACK(0x5C3A), PACK(0x5E7C), PACK(0x5FBE),

		PACK(0xE100), PACK(0xE0C2), PACK(0xE284), PACK(0xE346),

		PACK(0xE608), PACK(0xE7CA), PACK(0xE58C), PACK(0xE44E),

		PACK(0xEF10), PACK(0xEED2), PACK(0xEC94), PACK(0xED56),

		PACK(0xE818), PACK(0xE9DA), PACK(0xEB9C), PACK(0xEA5E),

		PACK(0xFD20), PACK(0xFCE2), PACK(0xFEA4), PACK(0xFF66),

		PACK(0xFA28), PACK(0xFBEA), PACK(0xF9AC), PACK(0xF86E),

		PACK(0xF330), PACK(0xF2F2), PACK(0xF0B4), PACK(0xF176),

		PACK(0xF438), PACK(0xF5FA), PACK(0xF7BC), PACK(0xF67E),

		PACK(0xD940), PACK(0xD882), PACK(0xDAC4), PACK(0xDB06),

		PACK(0xDE48), PACK(0xDF8A), PACK(0xDDCC), PACK(0xDC0E),

		PACK(0xD750), PACK(0xD692), PACK(0xD4D4), PACK(0xD516),

		PACK(0xD058), PACK(0xD19A), PACK(0xD3DC), PACK(0xD21E),

		PACK(0xC560), PACK(0xC4A2), PACK(0xC6E4), PACK(0xC726),

		PACK(0xC268), PACK(0xC3AA), PACK(0xC1EC), PACK(0xC02E),

		PACK(0xCB70), PACK(0xCAB2), PACK(0xC8F4), PACK(0xC936),

		PACK(0xCC78), PACK(0xCDBA), PACK(0xCFFC), PACK(0xCE3E),

		PACK(0x9180), PACK(0x9042), PACK(0x9204), PACK(0x93C6),

		PACK(0x9688), PACK(0x974A), PACK(0x950C), PACK(0x94CE),

		PACK(0x9F90), PACK(0x9E52), PACK(0x9C14), PACK(0x9DD6),

		PACK(0x9898), PACK(0x995A), PACK(0x9B1C), PACK(0x9ADE),

		PACK(0x8DA0), PACK(0x8C62), PACK(0x8E24), PACK(0x8FE6),

		PACK(0x8AA8), PACK(0x8B6A), PACK(0x892C), PACK(0x88EE),

		PACK(0x83B0), PACK(0x8272), PACK(0x8034), PACK(0x81F6),

		PACK(0x84B8), PACK(0x857A), PACK(0x873C), PACK(0x86FE),

		PACK(0xA9C0), PACK(0xA802), PACK(0xAA44), PACK(0xAB86),

		PACK(0xAEC8), PACK(0xAF0A), PACK(0xAD4C), PACK(0xAC8E),

		PACK(0xA7D0), PACK(0xA612), PACK(0xA454), PACK(0xA596),

		PACK(0xA0D8), PACK(0xA11A), PACK(0xA35C), PACK(0xA29E),

		PACK(0xB5E0), PACK(0xB422), PACK(0xB664), PACK(0xB7A6),

		PACK(0xB2E8), PACK(0xB32A), PACK(0xB16C), PACK(0xB0AE),

		PACK(0xBBF0), PACK(0xBA32), PACK(0xB874), PACK(0xB9B6),

		PACK(0xBCF8), PACK(0xBD3A), PACK(0xBF7C), PACK(0xBEBE) };

	while (1) {

		Z.hi ^= Htable[n].hi;

		Z.lo ^= Htable[n].lo;

		if ((u8 *)Xi==xi)	break;

		n = *(--xi);

		rem  = (size_t)Z.lo&0xff;

		Z.lo = (Z.hi<<56)|(Z.lo>>8);

		Z.hi = (Z.hi>>8);

		if (sizeof(size_t)==8)

			Z.hi ^= rem_8bit[rem];

		else

			Z.hi ^= (u64)rem_8bit[rem]<<32;

	}

	if (BYTE_ORDER == LITTLE_ENDIAN) {

#ifdef BSWAP8

		Xi[0] = BSWAP8(Z.hi);

		Xi[1] = BSWAP8(Z.lo);

#else

		u8 *p = (u8 *)Xi;

		u32 v;

		v = (u32)(Z.hi>>32);	PUTU32(p,v);

		v = (u32)(Z.hi);	PUTU32(p+4,v);

		v = (u32)(Z.lo>>32);	PUTU32(p+8,v);

		v = (u32)(Z.lo);	PUTU32(p+12,v);

#endif

	}

	else {

		Xi[0] = Z.hi;

		Xi[1] = Z.lo;

	}

}

#define GCM_MUL(ctx,Xi)   gcm_gmult_8bit(ctx->Xi.u,ctx->Htable)

#elif	TABLE_BITS==4

static void gcm_init_4bit(u128 Htable[16], u64 H[2])

{

	u128 V;

#if defined(OPENSSL_SMALL_FOOTPRINT)

	int  i;

#endif

#if defined(OPENSSL_SMALL_FOOTPRINT)

	for (Htable[8]=V, i=4; i>0; i>>=1) {

		REDUCE1BIT(V);

		Htable[i] = V;

	}

	for (i=2; i<16; i<<=1) {

		u128 *Hi = Htable+i;

		int   j;

		for (V=*Hi, j=1; j<i; ++j) {

			Hi[j].hi = V.hi^Htable[j].hi;

			Hi[j].lo = V.lo^Htable[j].lo;

		}

	}

#else

#endif

#if defined(GHASH_ASM) && (defined(__arm__) || defined(__arm))

	/*

	 * ARM assembler expects specific dword order in Htable.

	 */

	{

	int j;

	if (BYTE_ORDER == LITTLE_ENDIAN)

		for (j=0;j<16;++j) {

			V = Htable[j];

			Htable[j].hi = V.lo;

			Htable[j].lo = V.hi;

		}

	else

		for (j=0;j<16;++j) {

			V = Htable[j];

			Htable[j].hi = V.lo<<32|V.lo>>32;

			Htable[j].lo = V.hi<<32|V.hi>>32;

		}

	}

#endif

}

#ifndef GHASH_ASM

static const size_t rem_4bit[16] = {

	PACK(0x0000), PACK(0x1C20), PACK(0x3840), PACK(0x2460),

	PACK(0x7080), PACK(0x6CA0), PACK(0x48C0), PACK(0x54E0),

	PACK(0xE100), PACK(0xFD20), PACK(0xD940), PACK(0xC560),

	PACK(0x9180), PACK(0x8DA0), PACK(0xA9C0), PACK(0xB5E0) };

static void gcm_gmult_4bit(u64 Xi[2], const u128 Htable[16])

{

	u128 Z;

	int cnt = 15;

	size_t rem, nlo, nhi;

	nlo  = ((const u8 *)Xi)[15];

	nhi  = nlo>>4;

	nlo &= 0xf;

	Z.hi = Htable[nlo].hi;

	Z.lo = Htable[nlo].lo;

	while (1) {

		rem  = (size_t)Z.lo&0xf;

		Z.lo = (Z.hi<<60)|(Z.lo>>4);

		Z.hi = (Z.hi>>4);

		if (sizeof(size_t)==8)

			Z.hi ^= rem_4bit[rem];

		else

			Z.hi ^= (u64)rem_4bit[rem]<<32;

		Z.hi ^= Htable[nhi].hi;

		Z.lo ^= Htable[nhi].lo;

		if (--cnt<0)		break;

		nlo  = ((const u8 *)Xi)[cnt];

		nhi  = nlo>>4;

		nlo &= 0xf;

		rem  = (size_t)Z.lo&0xf;

		Z.lo = (Z.hi<<60)|(Z.lo>>4);

		Z.hi = (Z.hi>>4);

		if (sizeof(size_t)==8)

			Z.hi ^= rem_4bit[rem];

		else

			Z.hi ^= (u64)rem_4bit[rem]<<32;

		Z.hi ^= Htable[nlo].hi;

		Z.lo ^= Htable[nlo].lo;

	}

	if (BYTE_ORDER == LITTLE_ENDIAN) {

#ifdef BSWAP8

		Xi[0] = BSWAP8(Z.hi);

		Xi[1] = BSWAP8(Z.lo);

#else

		u8 *p = (u8 *)Xi;

		u32 v;

		v = (u32)(Z.hi>>32);	PUTU32(p,v);

		v = (u32)(Z.hi);	PUTU32(p+4,v);

		v = (u32)(Z.lo>>32);	PUTU32(p+8,v);

		v = (u32)(Z.lo);	PUTU32(p+12,v);

#endif

	}

	else {

		Xi[0] = Z.hi;

		Xi[1] = Z.lo;

	}

}

#if !defined(OPENSSL_SMALL_FOOTPRINT)

/*

 * Streamed gcm_mult_4bit, see CRYPTO_gcm128_[en|de]crypt for

 * details... Compiler-generated code doesn't seem to give any

 * performance improvement, at least not on x86[_64]. It's here

 * mostly as reference and a placeholder for possible future

 * non-trivial optimization[s]...

 */

static void gcm_ghash_4bit(u64 Xi[2],const u128 Htable[16],

				const u8 *inp,size_t len)

{

    u128 Z;

    int cnt;

    size_t rem, nlo, nhi;

#if 1

    do {

	cnt  = 15;

	nlo  = ((const u8 *)Xi)[15];

	nlo ^= inp[15];

	nhi  = nlo>>4;

	nlo &= 0xf;

	Z.hi = Htable[nlo].hi;

	Z.lo = Htable[nlo].lo;

	while (1) {

		rem  = (size_t)Z.lo&0xf;

		Z.lo = (Z.hi<<60)|(Z.lo>>4);

		Z.hi = (Z.hi>>4);

		if (sizeof(size_t)==8)

			Z.hi ^= rem_4bit[rem];

		else

			Z.hi ^= (u64)rem_4bit[rem]<<32;

		Z.hi ^= Htable[nhi].hi;

		Z.lo ^= Htable[nhi].lo;

		if (--cnt<0)		break;

		nlo  = ((const u8 *)Xi)[cnt];

		nlo ^= inp[cnt];

		nhi  = nlo>>4;

		nlo &= 0xf;

		rem  = (size_t)Z.lo&0xf;

		Z.lo = (Z.hi<<60)|(Z.lo>>4);

		Z.hi = (Z.hi>>4);

		if (sizeof(size_t)==8)

			Z.hi ^= rem_4bit[rem];

		else

			Z.hi ^= (u64)rem_4bit[rem]<<32;

		Z.hi ^= Htable[nlo].hi;

		Z.lo ^= Htable[nlo].lo;

	}

#else

    /*

     * Extra 256+16 bytes per-key plus 512 bytes shared tables

     * [should] give ~50% improvement... One could have PACK()-ed

     * the rem_8bit even here, but the priority is to minimize

     * cache footprint...

     */

    u128 Hshr4[16];	/* Htable shifted right by 4 bits */

    u8   Hshl4[16];	/* Htable shifted left  by 4 bits */

    static const unsigned short rem_8bit[256] = {

	0x0000, 0x01C2, 0x0384, 0x0246, 0x0708, 0x06CA, 0x048C, 0x054E,

	0x0E10, 0x0FD2, 0x0D94, 0x0C56, 0x0918, 0x08DA, 0x0A9C, 0x0B5E,

	0x1C20, 0x1DE2, 0x1FA4, 0x1E66, 0x1B28, 0x1AEA, 0x18AC, 0x196E,

	0x1230, 0x13F2, 0x11B4, 0x1076, 0x1538, 0x14FA, 0x16BC, 0x177E,

	0x3840, 0x3982, 0x3BC4, 0x3A06, 0x3F48, 0x3E8A, 0x3CCC, 0x3D0E,

	0x3650, 0x3792, 0x35D4, 0x3416, 0x3158, 0x309A, 0x32DC, 0x331E,

	0x2460, 0x25A2, 0x27E4, 0x2626, 0x2368, 0x22AA, 0x20EC, 0x212E,

	0x2A70, 0x2BB2, 0x29F4, 0x2836, 0x2D78, 0x2CBA, 0x2EFC, 0x2F3E,

	0x7080, 0x7142, 0x7304, 0x72C6, 0x7788, 0x764A, 0x740C, 0x75CE,

	0x7E90, 0x7F52, 0x7D14, 0x7CD6, 0x7998, 0x785A, 0x7A1C, 0x7BDE,

	0x6CA0, 0x6D62, 0x6F24, 0x6EE6, 0x6BA8, 0x6A6A, 0x682C, 0x69EE,

	0x62B0, 0x6372, 0x6134, 0x60F6, 0x65B8, 0x647A, 0x663C, 0x67FE,

	0x48C0, 0x4902, 0x4B44, 0x4A86, 0x4FC8, 0x4E0A, 0x4C4C, 0x4D8E,

	0x46D0, 0x4712, 0x4554, 0x4496, 0x41D8, 0x401A, 0x425C, 0x439E,

	0x54E0, 0x5522, 0x5764, 0x56A6, 0x53E8, 0x522A, 0x506C, 0x51AE,

	0x5AF0, 0x5B32, 0x5974, 0x58B6, 0x5DF8, 0x5C3A, 0x5E7C, 0x5FBE,

	0xE100, 0xE0C2, 0xE284, 0xE346, 0xE608, 0xE7CA, 0xE58C, 0xE44E,

	0xEF10, 0xEED2, 0xEC94, 0xED56, 0xE818, 0xE9DA, 0xEB9C, 0xEA5E,

	0xFD20, 0xFCE2, 0xFEA4, 0xFF66, 0xFA28, 0xFBEA, 0xF9AC, 0xF86E,

	0xF330, 0xF2F2, 0xF0B4, 0xF176, 0xF438, 0xF5FA, 0xF7BC, 0xF67E,

	0xD940, 0xD882, 0xDAC4, 0xDB06, 0xDE48, 0xDF8A, 0xDDCC, 0xDC0E,

	0xD750, 0xD692, 0xD4D4, 0xD516, 0xD058, 0xD19A, 0xD3DC, 0xD21E,

	0xC560, 0xC4A2, 0xC6E4, 0xC726, 0xC268, 0xC3AA, 0xC1EC, 0xC02E,

	0xCB70, 0xCAB2, 0xC8F4, 0xC936, 0xCC78, 0xCDBA, 0xCFFC, 0xCE3E,

	0x9180, 0x9042, 0x9204, 0x93C6, 0x9688, 0x974A, 0x950C, 0x94CE,

	0x9F90, 0x9E52, 0x9C14, 0x9DD6, 0x9898, 0x995A, 0x9B1C, 0x9ADE,

	0x8DA0, 0x8C62, 0x8E24, 0x8FE6, 0x8AA8, 0x8B6A, 0x892C, 0x88EE,

	0x83B0, 0x8272, 0x8034, 0x81F6, 0x84B8, 0x857A, 0x873C, 0x86FE,

	0xA9C0, 0xA802, 0xAA44, 0xAB86, 0xAEC8, 0xAF0A, 0xAD4C, 0xAC8E,

	0xA7D0, 0xA612, 0xA454, 0xA596, 0xA0D8, 0xA11A, 0xA35C, 0xA29E,

	0xB5E0, 0xB422, 0xB664, 0xB7A6, 0xB2E8, 0xB32A, 0xB16C, 0xB0AE,

	0xBBF0, 0xBA32, 0xB874, 0xB9B6, 0xBCF8, 0xBD3A, 0xBF7C, 0xBEBE };

    /*

     * This pre-processing phase slows down procedure by approximately

     * same time as it makes each loop spin faster. In other words

     * single block performance is approximately same as straightforward

     * "4-bit" implementation, and then it goes only faster...

     */

    for (cnt=0; cnt<16; ++cnt) {

	Z.hi = Htable[cnt].hi;

	Z.lo = Htable[cnt].lo;

	Hshr4[cnt].lo = (Z.hi<<60)|(Z.lo>>4);

	Hshr4[cnt].hi = (Z.hi>>4);

	Hshl4[cnt]    = (u8)(Z.lo<<4);

    }

    do {

	for (Z.lo=0, Z.hi=0, cnt=15; cnt; --cnt) {

		nlo  = ((const u8 *)Xi)[cnt];

		nlo ^= inp[cnt];

		nhi  = nlo>>4;

		nlo &= 0xf;

		Z.hi ^= Htable[nlo].hi;

		Z.lo ^= Htable[nlo].lo;

		rem = (size_t)Z.lo&0xff;

		Z.lo = (Z.hi<<56)|(Z.lo>>8);

		Z.hi = (Z.hi>>8);

		Z.hi ^= Hshr4[nhi].hi;

		Z.lo ^= Hshr4[nhi].lo;

		Z.hi ^= (u64)rem_8bit[rem^Hshl4[nhi]]<<48;

	}

	nlo  = ((const u8 *)Xi)[0];

	nlo ^= inp[0];

	nhi  = nlo>>4;

	nlo &= 0xf;

	Z.hi ^= Htable[nlo].hi;

	Z.lo ^= Htable[nlo].lo;

	rem = (size_t)Z.lo&0xf;

	Z.lo = (Z.hi<<60)|(Z.lo>>4);

	Z.hi = (Z.hi>>4);

	Z.hi ^= Htable[nhi].hi;

	Z.lo ^= Htable[nhi].lo;

	Z.hi ^= ((u64)rem_8bit[rem<<4])<<48;

#endif

	if (BYTE_ORDER == LITTLE_ENDIAN) {

#ifdef BSWAP8

		Xi[0] = BSWAP8(Z.hi);

		Xi[1] = BSWAP8(Z.lo);

#else

		u8 *p = (u8 *)Xi;

		u32 v;

		v = (u32)(Z.hi>>32);	PUTU32(p,v);

		v = (u32)(Z.hi);	PUTU32(p+4,v);

		v = (u32)(Z.lo>>32);	PUTU32(p+8,v);

		v = (u32)(Z.lo);	PUTU32(p+12,v);

#endif

	}

	else {

		Xi[0] = Z.hi;

		Xi[1] = Z.lo;

	}

    } while (inp+=16, len-=16);

}

#endif

#else

void gcm_gmult_4bit(u64 Xi[2],const u128 Htable[16]);

void gcm_ghash_4bit(u64 Xi[2],const u128 Htable[16],const u8 *inp,size_t len);

#endif

#define GCM_MUL(ctx,Xi)   gcm_gmult_4bit(ctx->Xi.u,ctx->Htable)

#if defined(GHASH_ASM) || !defined(OPENSSL_SMALL_FOOTPRINT)

#define GHASH(ctx,in,len) gcm_ghash_4bit((ctx)->Xi.u,(ctx)->Htable,in,len)

/* GHASH_CHUNK is "stride parameter" missioned to mitigate cache

 * trashing effect. In other words idea is to hash data while it's

 * still in L1 cache after encryption pass... */

#define GHASH_CHUNK       (3*1024)

#endif

#else	/* TABLE_BITS */

static void gcm_gmult_1bit(u64 Xi[2],const u64 H[2])

{

	u128 V,Z = { 0,0 };

	long X;

	int  i,j;

	const long *xi = (const long *)Xi;

	V.hi = H[0];	/* H is in host byte order, no byte swapping */

	V.lo = H[1];

	for (j=0; j<16/sizeof(long); ++j) {

		if (BYTE_ORDER == LITTLE_ENDIAN) {

			if (sizeof(long)==8) {

#ifdef BSWAP8

				X = (long)(BSWAP8(xi[j]));

#else

				const u8 *p = (const u8 *)(xi+j);

				X = (long)((u64)GETU32(p)<<32|GETU32(p+4));

#endif

			}

			else {

				const u8 *p = (const u8 *)(xi+j);

				X = (long)GETU32(p);

			}

		}

		else

			X = xi[j];

		for (i=0; i<8*sizeof(long); ++i, X<<=1) {

			u64 M = (u64)(X>>(8*sizeof(long)-1));

			Z.hi ^= V.hi&M;

			Z.lo ^= V.lo&M;

			REDUCE1BIT(V);

		}

	}

	if (BYTE_ORDER == LITTLE_ENDIAN) {

#ifdef BSWAP8

		Xi[0] = BSWAP8(Z.hi);

		Xi[1] = BSWAP8(Z.lo);

#else

		u8 *p = (u8 *)Xi;

		u32 v;

		v = (u32)(Z.hi>>32);	PUTU32(p,v);

		v = (u32)(Z.hi);	PUTU32(p+4,v);

		v = (u32)(Z.lo>>32);	PUTU32(p+8,v);

		v = (u32)(Z.lo);	PUTU32(p+12,v);

#endif

	}

	else {

		Xi[0] = Z.hi;

		Xi[1] = Z.lo;

	}

}

#define GCM_MUL(ctx,Xi)	  gcm_gmult_1bit(ctx->Xi.u,ctx->H.u)

#endif

#if	TABLE_BITS==4 && defined(GHASH_ASM)

# if	!defined(I386_ONLY) && \

	(defined(__i386)	|| defined(__i386__)	|| \

	 defined(__x86_64)	|| defined(__x86_64__)	|| \

	 defined(_M_IX86)	|| defined(_M_AMD64)	|| defined(_M_X64))

#  define GHASH_ASM_X86_OR_64

#  define GCM_FUNCREF_4BIT

extern unsigned int OPENSSL_ia32cap_P[2];

void gcm_init_clmul(u128 Htable[16],const u64 Xi[2]);

void gcm_gmult_clmul(u64 Xi[2],const u128 Htable[16]);

void gcm_ghash_clmul(u64 Xi[2],const u128 Htable[16],const u8 *inp,size_t len);

#  if	defined(__i386) || defined(__i386__) || defined(_M_IX86)

#   define GHASH_ASM_X86

void gcm_gmult_4bit_mmx(u64 Xi[2],const u128 Htable[16]);

void gcm_ghash_4bit_mmx(u64 Xi[2],const u128 Htable[16],const u8 *inp,size_t len);

void gcm_gmult_4bit_x86(u64 Xi[2],const u128 Htable[16]);

void gcm_ghash_4bit_x86(u64 Xi[2],const u128 Htable[16],const u8 *inp,size_t len);

#  endif

# elif defined(__arm__) || defined(__arm)

#  include "arm_arch.h"

#  if __ARM_ARCH__>=7

#   define GHASH_ASM_ARM

#   define GCM_FUNCREF_4BIT

void gcm_gmult_neon(u64 Xi[2],const u128 Htable[16]);

void gcm_ghash_neon(u64 Xi[2],const u128 Htable[16],const u8 *inp,size_t len);

#  endif

# endif

#endif

#ifdef GCM_FUNCREF_4BIT

# undef  GCM_MUL

# define GCM_MUL(ctx,Xi)	(*gcm_gmult_p)(ctx->Xi.u,ctx->Htable)

# ifdef GHASH

#  undef  GHASH

#  define GHASH(ctx,in,len)	(*gcm_ghash_p)(ctx->Xi.u,ctx->Htable,in,len)

# endif

#endif

void CRYPTO_gcm128_init(GCM128_CONTEXT *ctx,void *key,block128_f block)

	if (BYTE_ORDER == LITTLE_ENDIAN) {

		/* H is stored in host byte order */

#ifdef BSWAP8

#else

		u8 *p = ctx->H.c;

		u64 hi,lo;

		hi = (u64)GETU32(p)  <<32|GETU32(p+4);

		lo = (u64)GETU32(p+8)<<32|GETU32(p+12);

		ctx->H.u[0] = hi;

		ctx->H.u[1] = lo;

#endif

	}

#if	TABLE_BITS==8

	gcm_init_8bit(ctx->Htable,ctx->H.u);

#elif	TABLE_BITS==4

# if	defined(GHASH_ASM_X86_OR_64)

#  if	!defined(GHASH_ASM_X86) || defined(OPENSSL_IA32_SSE2)

	    OPENSSL_ia32cap_P[1]&(1<<1) ) {	/* check PCLMULQDQ bit */

	}

#  endif

#  if	defined(GHASH_ASM_X86)			/* x86 only */

#   if	defined(OPENSSL_IA32_SSE2)

	if (OPENSSL_ia32cap_P[0]&(1<<25)) {	/* check SSE bit */

#   else

	if (OPENSSL_ia32cap_P[0]&(1<<23)) {	/* check MMX bit */

#   endif

		ctx->gmult = gcm_gmult_4bit_mmx;

		ctx->ghash = gcm_ghash_4bit_mmx;

	} else {

		ctx->gmult = gcm_gmult_4bit_x86;

		ctx->ghash = gcm_ghash_4bit_x86;

	}

#  else

#  endif

# elif	defined(GHASH_ASM_ARM)

	if (OPENSSL_armcap_P & ARMV7_NEON) {

		ctx->gmult = gcm_gmult_neon;

		ctx->ghash = gcm_ghash_neon;

	} else {

		gcm_init_4bit(ctx->Htable,ctx->H.u);

		ctx->gmult = gcm_gmult_4bit;

		ctx->ghash = gcm_ghash_4bit;

	}

# else

	gcm_init_4bit(ctx->Htable,ctx->H.u);

# endif

#endif

}

void CRYPTO_gcm128_setiv(GCM128_CONTEXT *ctx,const unsigned char *iv,size_t len)

	unsigned int ctr;

#ifdef GCM_FUNCREF_4BIT

#endif

	}

	else {

		size_t i;

		}

		}

		if (BYTE_ORDER == LITTLE_ENDIAN) {

#ifdef BSWAP8

#else

			ctx->Yi.c[8]  ^= (u8)(len0>>56);

			ctx->Yi.c[9]  ^= (u8)(len0>>48);

			ctx->Yi.c[10] ^= (u8)(len0>>40);

			ctx->Yi.c[11] ^= (u8)(len0>>32);

			ctx->Yi.c[12] ^= (u8)(len0>>24);

			ctx->Yi.c[13] ^= (u8)(len0>>16);

			ctx->Yi.c[14] ^= (u8)(len0>>8);

			ctx->Yi.c[15] ^= (u8)(len0);

#endif

		}

		else

			ctx->Yi.u[1]  ^= len0;

		if (BYTE_ORDER == LITTLE_ENDIAN)

#ifdef BSWAP4

#else

			ctr = GETU32(ctx->Yi.c+12);

#endif

		else

			ctr = ctx->Yi.d[3];

	}

	if (BYTE_ORDER == LITTLE_ENDIAN)

#ifdef BSWAP4

#else

		PUTU32(ctx->Yi.c+12,ctr);

#endif

	else

		ctx->Yi.d[3] = ctr;

int CRYPTO_gcm128_aad(GCM128_CONTEXT *ctx,const unsigned char *aad,size_t len)

	size_t i;

	unsigned int n;

#ifdef GCM_FUNCREF_4BIT

# ifdef GHASH

	void (*gcm_ghash_p)(u64 Xi[2],const u128 Htable[16],

# endif

#endif

		}

		else {

		}

	}

#ifdef GHASH

	}

#else

	while (len>=16) {

		for (i=0; i<16; ++i) ctx->Xi.c[i] ^= aad[i];

		GCM_MUL(ctx,Xi);

		aad += 16;

		len -= 16;

	}

#endif

	}

}

int CRYPTO_gcm128_encrypt(GCM128_CONTEXT *ctx,

		const unsigned char *in, unsigned char *out,

		size_t len)

	unsigned int n, ctr;

	size_t i;

#ifdef GCM_FUNCREF_4BIT

# ifdef GHASH

	void (*gcm_ghash_p)(u64 Xi[2],const u128 Htable[16],

# endif

#endif

		/* First call to encrypt finalizes GHASH(AAD) */

	}

	if (BYTE_ORDER == LITTLE_ENDIAN)

#ifdef BSWAP4

#else

		ctr = GETU32(ctx->Yi.c+12);

#endif

	else

		ctr = ctx->Yi.d[3];

#if !defined(OPENSSL_SMALL_FOOTPRINT)

	if (16%sizeof(size_t) == 0) do {	/* always true actually */

			}

			else {

			}

		}

#ifdef __STRICT_ALIGNMENT

		if (((size_t)in|(size_t)out)%sizeof(size_t) != 0)

			break;

#endif

#if defined(GHASH) && defined(GHASH_CHUNK)

			if (BYTE_ORDER == LITTLE_ENDIAN)

#ifdef BSWAP4

#else

				PUTU32(ctx->Yi.c+12,ctr);

#endif

			else

				ctx->Yi.d[3] = ctr;

		    }

		}

			if (BYTE_ORDER == LITTLE_ENDIAN)

#ifdef BSWAP4

#else

				PUTU32(ctx->Yi.c+12,ctr);

#endif

			else

				ctx->Yi.d[3] = ctr;

		    }