/* md4.c

 *

 * Copyright (C) 2006-2023 wolfSSL Inc.

 *

 * This file is part of wolfSSL.

 *

 * wolfSSL is free software; you can redistribute it and/or modify

 * it under the terms of the GNU General Public License as published by

 * the Free Software Foundation; either version 2 of the License, or

 * (at your option) any later version.

 *

 * wolfSSL is distributed in the hope that it will be useful,

 * but WITHOUT ANY WARRANTY; without even the implied warranty of

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

 * GNU General Public License for more details.

 *

 * You should have received a copy of the GNU General Public License

 * along with this program; if not, write to the Free Software

 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1335, USA

 */

#ifdef HAVE_CONFIG_H

    #include <config.h>

#endif

#include <wolfssl/wolfcrypt/settings.h>

#ifndef NO_MD4

#include <wolfssl/wolfcrypt/md4.h>

#ifdef NO_INLINE

    #include <wolfssl/wolfcrypt/misc.h>

#else

    #define WOLFSSL_MISC_INCLUDED

    #include <wolfcrypt/src/misc.c>

#endif

void wc_InitMd4(Md4* md4)

{

    md4->digest[0] = 0x67452301L;

    md4->digest[1] = 0xefcdab89L;

    md4->digest[2] = 0x98badcfeL;

    md4->digest[3] = 0x10325476L;

    md4->buffLen = 0;

    md4->loLen   = 0;

    md4->hiLen   = 0;

}

static void Transform(Md4* md4)

{

#define F(x, y, z) ((z) ^ ((x) & ((y) ^ (z))))

#define G(x, y, z) (((x) & (y)) | ((x) & (z)) | ((y) & (z)))

#define H(x, y, z) ((x) ^ (y) ^ (z))

    /* Copy context->state[] to working vars  */

    word32 A = md4->digest[0];

    word32 B = md4->digest[1];

    word32 C = md4->digest[2];

    word32 D = md4->digest[3];

#define function(a,b,c,d,k,s) (a)=rotlFixed((a)+F(b,c,d)+md4->buffer[k],s);

    function(A,B,C,D, 0, 3);

    function(D,A,B,C, 1, 7);

    function(C,D,A,B, 2,11);

    function(B,C,D,A, 3,19);

    function(A,B,C,D, 4, 3);

    function(D,A,B,C, 5, 7);

    function(C,D,A,B, 6,11);

    function(B,C,D,A, 7,19);

    function(A,B,C,D, 8, 3);

    function(D,A,B,C, 9, 7);

    function(C,D,A,B,10,11);

    function(B,C,D,A,11,19);

    function(A,B,C,D,12, 3);

    function(D,A,B,C,13, 7);

    function(C,D,A,B,14,11);

    function(B,C,D,A,15,19);

#undef function

#define function(a,b,c,d,k,s) \

    (a)=rotlFixed((a)+G(b,c,d)+md4->buffer[k]+0x5a827999,s);

    function(A,B,C,D, 0, 3);

    function(D,A,B,C, 4, 5);

    function(C,D,A,B, 8, 9);

    function(B,C,D,A,12,13);

    function(A,B,C,D, 1, 3);

    function(D,A,B,C, 5, 5);

    function(C,D,A,B, 9, 9);

    function(B,C,D,A,13,13);

    function(A,B,C,D, 2, 3);

    function(D,A,B,C, 6, 5);

    function(C,D,A,B,10, 9);

    function(B,C,D,A,14,13);

    function(A,B,C,D, 3, 3);

    function(D,A,B,C, 7, 5);

    function(C,D,A,B,11, 9);

    function(B,C,D,A,15,13);

#undef function

#define function(a,b,c,d,k,s) \

    (a)=rotlFixed((a)+H(b,c,d)+md4->buffer[k]+0x6ed9eba1,s);

    function(A,B,C,D, 0, 3);

    function(D,A,B,C, 8, 9);

    function(C,D,A,B, 4,11);

    function(B,C,D,A,12,15);

    function(A,B,C,D, 2, 3);

    function(D,A,B,C,10, 9);

    function(C,D,A,B, 6,11);

    function(B,C,D,A,14,15);

    function(A,B,C,D, 1, 3);

    function(D,A,B,C, 9, 9);

    function(C,D,A,B, 5,11);

    function(B,C,D,A,13,15);

    function(A,B,C,D, 3, 3);

    function(D,A,B,C,11, 9);

    function(C,D,A,B, 7,11);

    function(B,C,D,A,15,15);

    /* Add the working vars back into digest state[]  */

    md4->digest[0] += A;

    md4->digest[1] += B;

    md4->digest[2] += C;

    md4->digest[3] += D;

}

static WC_INLINE void AddLength(Md4* md4, word32 len)

{

    word32 tmp = md4->loLen;

    if ( (md4->loLen += len) < tmp)

        md4->hiLen++;                       /* carry low to high */

}

void wc_Md4Update(Md4* md4, const byte* data, word32 len)

{

    /* do block size increments */

    byte* local = (byte*)md4->buffer;

    while (len) {

        word32 add = min(len, MD4_BLOCK_SIZE - md4->buffLen);

        XMEMCPY(&local[md4->buffLen], data, add);

        md4->buffLen += add;

        data         += add;

        len          -= add;

        if (md4->buffLen == MD4_BLOCK_SIZE) {

            #ifdef BIG_ENDIAN_ORDER

                ByteReverseWords(md4->buffer, md4->buffer, MD4_BLOCK_SIZE);

            #endif

            Transform(md4);

            AddLength(md4, MD4_BLOCK_SIZE);

            md4->buffLen = 0;

        }

    }

}

void wc_Md4Final(Md4* md4, byte* hash)

{

    byte* local = (byte*)md4->buffer;

    AddLength(md4, md4->buffLen);               /* before adding pads */

    local[md4->buffLen++] = 0x80;  /* add 1 */

    /* pad with zeros */

    if (md4->buffLen > MD4_PAD_SIZE) {

        XMEMSET(&local[md4->buffLen], 0, MD4_BLOCK_SIZE - md4->buffLen);

        md4->buffLen += MD4_BLOCK_SIZE - md4->buffLen;

        #ifdef BIG_ENDIAN_ORDER

            ByteReverseWords(md4->buffer, md4->buffer, MD4_BLOCK_SIZE);

        #endif

        Transform(md4);

        md4->buffLen = 0;

    }

    XMEMSET(&local[md4->buffLen], 0, MD4_PAD_SIZE - md4->buffLen);

    /* put lengths in bits */

    md4->hiLen = (md4->loLen >> (8*sizeof(md4->loLen) - 3)) +

                 (md4->hiLen << 3);

    md4->loLen = md4->loLen << 3;

    /* store lengths */

    #ifdef BIG_ENDIAN_ORDER

        ByteReverseWords(md4->buffer, md4->buffer, MD4_BLOCK_SIZE);

    #endif

    /* ! length ordering dependent on digest endian type ! */

    XMEMCPY(&local[MD4_PAD_SIZE], &md4->loLen, sizeof(word32));

    XMEMCPY(&local[MD4_PAD_SIZE + sizeof(word32)], &md4->hiLen, sizeof(word32));

    Transform(md4);

    #ifdef BIG_ENDIAN_ORDER

        ByteReverseWords(md4->digest, md4->digest, MD4_DIGEST_SIZE);

    #endif

    XMEMCPY(hash, md4->digest, MD4_DIGEST_SIZE);

    wc_InitMd4(md4);  /* reset state */

}

#endif /* NO_MD4 */