/* This MD5 code is based on code from Dynamics -- HUT Mobile IP
 * Copyright (C) 1998-2001, Dynamics group
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation. See README and COPYING for
 * more details.

    Module Name:
    md5.c

    Abstract:
        contain MD5 and AES cipher algorithm
        
    Revision History:
    Who         When            What
    --------    ----------      ----------------------------------------------
    jan         10-28-03        Initial
 */
#include "rt_config.h"

/**
 * md5_mac:
 * @key: pointer to the key used for MAC generation
 * @key_len: length of the key in bytes
 * @data: pointer to the data area for which the MAC is generated
 * @data_len: length of the data in bytes
 * @mac: pointer to the buffer holding space for the MAC; the buffer should
 * have space for 128-bit (16 bytes) MD5 hash value
 *
 * md5_mac() determines the message authentication code by using secure hash
 * MD5(key | data | key).
 */
void md5_mac(u8 *key, size_t key_len, u8 *data, size_t data_len, u8 *mac)
{
    MD5_CTX context;

    MD5Init(&context);
    MD5Update(&context, key, key_len);
    MD5Update(&context, data, data_len);
    MD5Update(&context, key, key_len);
    MD5Final(mac, &context);
}

/**
 * hmac_md5:
 * @key: pointer to the key used for MAC generation
 * @key_len: length of the key in bytes
 * @data: pointer to the data area for which the MAC is generated
 * @data_len: length of the data in bytes
 * @mac: pointer to the buffer holding space for the MAC; the buffer should
 * have space for 128-bit (16 bytes) MD5 hash value
 *
 * hmac_md5() determines the message authentication code using HMAC-MD5.
 * This implementation is based on the sample code presented in RFC 2104.
 */
void hmac_md5(u8 *key, size_t key_len, u8 *data, size_t data_len, u8 *mac)
{
    MD5_CTX context;
    u8 k_ipad[65]; /* inner padding - key XORd with ipad */
    u8 k_opad[65]; /* outer padding - key XORd with opad */
    u8 tk[16];
    int i;

    //assert(key != NULL && data != NULL && mac != NULL);

    /* if key is longer than 64 bytes reset it to key = MD5(key) */
    if (key_len > 64) {
        MD5_CTX ttcontext;

        MD5Init(&ttcontext);
        MD5Update(&ttcontext, key, key_len);
        MD5Final(tk, &ttcontext);
        //key=(PUCHAR)ttcontext.buf;
        key = tk;
        key_len = 16;
    }

    /* the HMAC_MD5 transform looks like:
     *
     * MD5(K XOR opad, MD5(K XOR ipad, text))
     *
     * where K is an n byte key
     * ipad is the byte 0x36 repeated 64 times
     * opad is the byte 0x5c repeated 64 times
     * and text is the data being protected */

    /* start out by storing key in pads */
    NdisZeroMemory(k_ipad, sizeof(k_ipad));
    NdisZeroMemory(k_opad,  sizeof(k_opad));
    //assert(key_len < sizeof(k_ipad));
    NdisMoveMemory(k_ipad, key, key_len);
    NdisMoveMemory(k_opad, key, key_len);

    /* XOR key with ipad and opad values */
    for (i = 0; i < 64; i++) {
        k_ipad[i] ^= 0x36;
        k_opad[i] ^= 0x5c;
    }

    /* perform inner MD5 */
    MD5Init(&context);                   /* init context for 1st pass */
    MD5Update(&context, k_ipad, 64);     /* start with inner pad */
    MD5Update(&context, data, data_len); /* then text of datagram */
    MD5Final(mac, &context);             /* finish up 1st pass */

    /* perform outer MD5 */
    MD5Init(&context);                   /* init context for 2nd pass */
    MD5Update(&context, k_opad, 64);     /* start with outer pad */
    MD5Update(&context, mac, 16);        /* then results of 1st hash */
    MD5Final(mac, &context);             /* finish up 2nd pass */
}


/* ===== start - public domain MD5 implementation ===== */
/*
 * This code implements the MD5 message-digest algorithm.
 * The algorithm is due to Ron Rivest.  This code was
 * written by Colin Plumb in 1993, no copyright is claimed.
 * This code is in the public domain; do with it what you wish.
 *
 * Equivalent code is available from RSA Data Security, Inc.
 * This code has been tested against that, and is equivalent,
 * except that you don't need to include two pages of legalese
 * with every copy.
 *
 * To compute the message digest of a chunk of bytes, declare an
 * MD5Context structure, pass it to MD5Init, call MD5Update as
 * needed on buffers full of bytes, and then call MD5Final, which
 * will fill a supplied 16-byte array with the digest.
 */

#ifndef BIG_ENDIAN
#define byteReverse(buf, len)   /* Nothing */
#else
void byteReverse(unsigned char *buf, unsigned longs);
void byteReverse(unsigned char *buf, unsigned longs)
{
    do {
        *(ULONG *)buf = SWAP32(*(ULONG *)buf);
        buf += 4;
    } while (--longs);
}
#endif

/*
 * Start MD5 accumulation.  Set bit count to 0 and buffer to mysterious
 * initialization constants.
 */
void MD5Init(struct MD5Context *ctx)
{
    ctx->buf[0] = 0x67452301;
    ctx->buf[1] = 0xefcdab89;
    ctx->buf[2] = 0x98badcfe;
    ctx->buf[3] = 0x10325476;

    ctx->bits[0] = 0;
    ctx->bits[1] = 0;
}

/*
 * Update context to reflect the concatenation of another buffer full
 * of bytes.
 */
void MD5Update(struct MD5Context *ctx, unsigned char *buf, unsigned len)
{
    u32 t;

    /* Update bitcount */

    t = ctx->bits[0];
    if ((ctx->bits[0] = t + ((u32) len << 3)) < t)
        ctx->bits[1]++;     /* Carry from low to high */
    ctx->bits[1] += len >> 29;

    t = (t >> 3) & 0x3f;    /* Bytes already in shsInfo->data */

    /* Handle any leading odd-sized chunks */

    if (t) {
        unsigned char *p = (unsigned char *) ctx->in + t;

        t = 64 - t;
        if (len < t) {
            NdisMoveMemory(p, buf, len);
            return;
        }
        NdisMoveMemory(p, buf, t);
        byteReverse(ctx->in, 16);
        MD5Transform(ctx->buf, (u32 *) ctx->in);
        buf += t;
        len -= t;
    }
    /* Process data in 64-byte chunks */

    while (len >= 64) {
        NdisMoveMemory(ctx->in, buf, 64);
        byteReverse(ctx->in, 16);
        MD5Transform(ctx->buf, (u32 *) ctx->in);
        buf += 64;
        len -= 64;
    }

    /* Handle any remaining bytes of data. */

    NdisMoveMemory(ctx->in, buf, len);
}

/*
 * Final wrapup - pad to 64-byte boundary with the bit pattern
 * 1 0* (64-bit count of bits processed, MSB-first)
 */
void MD5Final(unsigned char digest[16], struct MD5Context *ctx)
{
    unsigned count;
    unsigned char *p;

    /* Compute number of bytes mod 64 */
    count = (ctx->bits[0] >> 3) & 0x3F;

    /* Set the first char of padding to 0x80.  This is safe since there is
       always at least one byte free */
    p = ctx->in + count;
    *p++ = 0x80;

    /* Bytes of padding needed to make 64 bytes */
    count = 64 - 1 - count;

    /* Pad out to 56 mod 64 */
    if (count < 8) {
        /* Two lots of padding:  Pad the first block to 64 bytes */
        NdisZeroMemory(p, count);
        byteReverse(ctx->in, 16);
        MD5Transform(ctx->buf, (u32 *) ctx->in);

        /* Now fill the next block with 56 bytes */
        NdisZeroMemory(ctx->in, 56);
    } else {
        /* Pad block to 56 bytes */
        NdisZeroMemory(p,  count - 8);
    }
    byteReverse(ctx->in, 14);

    /* Append length in bits and transform */
    ((u32 *) ctx->in)[14] = ctx->bits[0];
    ((u32 *) ctx->in)[15] = ctx->bits[1];

    MD5Transform(ctx->buf, (u32 *) ctx->in);
    byteReverse((unsigned char *) ctx->buf, 4);
    NdisMoveMemory(digest, ctx->buf, 16);
    NdisZeroMemory(ctx,  sizeof(ctx));  /* In case it's sensitive */
}

//#ifndef ASM_MD5
#if 1

/* The four core functions - F1 is optimized somewhat */

/* #define F1(x, y, z) (x & y | ~x & z) */
#define F1(x, y, z) (z ^ (x & (y ^ z)))
#define F2(x, y, z) F1(z, x, y)
#define F3(x, y, z) (x ^ y ^ z)
#define F4(x, y, z) (y ^ (x | ~z))

/* This is the central step in the MD5 algorithm. */
#define MD5STEP(f, w, x, y, z, data, s) \
    ( w += f(x, y, z) + data,  w =( w<<s | w>>(32-s))&0xffffffff,  w += x )

/*
 * The core of the MD5 algorithm, this alters an existing MD5 hash to
 * reflect the addition of 16 longwords of new data.  MD5Update blocks
 * the data and converts bytes into longwords for this routine.
 */
void MD5Transform(u32 buf[4], u32 in[16])
{
    register u32 a, b, c, d;

    a = buf[0];
    b = buf[1];
    c = buf[2];
    d = buf[3];

    MD5STEP(F1, a, b, c, d, in[0] + 0xd76aa478, 7);
    MD5STEP(F1, d, a, b, c, in[1] + 0xe8c7b756, 12);
    MD5STEP(F1, c, d, a, b, in[2] + 0x242070db, 17);
    MD5STEP(F1, b, c, d, a, in[3] + 0xc1bdceee, 22);
    MD5STEP(F1, a, b, c, d, in[4] + 0xf57c0faf, 7);
    MD5STEP(F1, d, a, b, c, in[5] + 0x4787c62a, 12);
    MD5STEP(F1, c, d, a, b, in[6] + 0xa8304613, 17);
    MD5STEP(F1, b, c, d, a, in[7] + 0xfd469501, 22);
    MD5STEP(F1, a, b, c, d, in[8] + 0x698098d8, 7);
    MD5STEP(F1, d, a, b, c, in[9] + 0x8b44f7af, 12);
    MD5STEP(F1, c, d, a, b, in[10] + 0xffff5bb1, 17);
    MD5STEP(F1, b, c, d, a, in[11] + 0x895cd7be, 22);
    MD5STEP(F1, a, b, c, d, in[12] + 0x6b901122, 7);
    MD5STEP(F1, d, a, b, c, in[13] + 0xfd987193, 12);
    MD5STEP(F1, c, d, a, b, in[14] + 0xa679438e, 17);
    MD5STEP(F1, b, c, d, a, in[15] + 0x49b40821, 22);

    MD5STEP(F2, a, b, c, d, in[1] + 0xf61e2562, 5);
    MD5STEP(F2, d, a, b, c, in[6] + 0xc040b340, 9);
    MD5STEP(F2, c, d, a, b, in[11] + 0x265e5a51, 14);
    MD5STEP(F2, b, c, d, a, in[0] + 0xe9b6c7aa, 20);
    MD5STEP(F2, a, b, c, d, in[5] + 0xd62f105d, 5);
    MD5STEP(F2, d, a, b, c, in[10] + 0x02441453, 9);
    MD5STEP(F2, c, d, a, b, in[15] + 0xd8a1e681, 14);
    MD5STEP(F2, b, c, d, a, in[4] + 0xe7d3fbc8, 20);
    MD5STEP(F2, a, b, c, d, in[9] + 0x21e1cde6, 5);
    MD5STEP(F2, d, a, b, c, in[14] + 0xc33707d6, 9);
    MD5STEP(F2, c, d, a, b, in[3] + 0xf4d50d87, 14);
    MD5STEP(F2, b, c, d, a, in[8] + 0x455a14ed, 20);
    MD5STEP(F2, a, b, c, d, in[13] + 0xa9e3e905, 5);
    MD5STEP(F2, d, a, b, c, in[2] + 0xfcefa3f8, 9);
    MD5STEP(F2, c, d, a, b, in[7] + 0x676f02d9, 14);
    MD5STEP(F2, b, c, d, a, in[12] + 0x8d2a4c8a, 20);

    MD5STEP(F3, a, b, c, d, in[5] + 0xfffa3942, 4);
    MD5STEP(F3, d, a, b, c, in[8] + 0x8771f681, 11);
    MD5STEP(F3, c, d, a, b, in[11] + 0x6d9d6122, 16);
    MD5STEP(F3, b, c, d, a, in[14] + 0xfde5380c, 23);
    MD5STEP(F3, a, b, c, d, in[1] + 0xa4beea44, 4);
    MD5STEP(F3, d, a, b, c, in[4] + 0x4bdecfa9, 11);
    MD5STEP(F3, c, d, a, b, in[7] + 0xf6bb4b60, 16);
    MD5STEP(F3, b, c, d, a, in[10] + 0xbebfbc70, 23);
    MD5STEP(F3, a, b, c, d, in[13] + 0x289b7ec6, 4);
    MD5STEP(F3, d, a, b, c, in[0] + 0xeaa127fa, 11);
    MD5STEP(F3, c, d, a, b, in[3] + 0xd4ef3085, 16);
    MD5STEP(F3, b, c, d, a, in[6] + 0x04881d05, 23);
    MD5STEP(F3, a, b, c, d, in[9] + 0xd9d4d039, 4);
    MD5STEP(F3, d, a, b, c, in[12] + 0xe6db99e5, 11);
    MD5STEP(F3, c, d, a, b, in[15] + 0x1fa27cf8, 16);
    MD5STEP(F3, b, c, d, a, in[2] + 0xc4ac5665, 23);

    MD5STEP(F4, a, b, c, d, in[0] + 0xf4292244, 6);
    MD5STEP(F4, d, a, b, c, in[7] + 0x432aff97, 10);
    MD5STEP(F4, c, d, a, b, in[14] + 0xab9423a7, 15);
    MD5STEP(F4, b, c, d, a, in[5] + 0xfc93a039, 21);
    MD5STEP(F4, a, b, c, d, in[12] + 0x655b59c3, 6);
    MD5STEP(F4, d, a, b, c, in[3] + 0x8f0ccc92, 10);
    MD5STEP(F4, c, d, a, b, in[10] + 0xffeff47d, 15);
    MD5STEP(F4, b, c, d, a, in[1] + 0x85845dd1, 21);
    MD5STEP(F4, a, b, c, d, in[8] + 0x6fa87e4f, 6);
    MD5STEP(F4, d, a, b, c, in[15] + 0xfe2ce6e0, 10);
    MD5STEP(F4, c, d, a, b, in[6] + 0xa3014314, 15);
    MD5STEP(F4, b, c, d, a, in[13] + 0x4e0811a1, 21);
    MD5STEP(F4, a, b, c, d, in[4] + 0xf7537e82, 6);
    MD5STEP(F4, d, a, b, c, in[11] + 0xbd3af235, 10);
    MD5STEP(F4, c, d, a, b, in[2] + 0x2ad7d2bb, 15);
    MD5STEP(F4, b, c, d, a, in[9] + 0xeb86d391, 21);

    buf[0] += a;
    buf[1] += b;
    buf[2] += c;
    buf[3] += d;
}
#endif

void SHAInit(SHA_CTX *ctx) {
    int i;
 
    ctx->lenW = 0;
    ctx->sizeHi = ctx->sizeLo = 0;
 
    /* Initialize H with the magic constants (see FIPS180 for constants)
     */
    ctx->H[0] = 0x67452301L;
    ctx->H[1] = 0xefcdab89L;
    ctx->H[2] = 0x98badcfeL;
    ctx->H[3] = 0x10325476L;
    ctx->H[4] = 0xc3d2e1f0L;
 
    for (i = 0; i < 80; i++)
        ctx->W[i] = 0;
 }

#define SHA_ROTL(X,n) ((((X) << (n)) | ((X) >> (32-(n)))) & 0xffffffffL)
 
void SHAHashBlock(SHA_CTX *ctx) {
    int t;
    unsigned long A,B,C,D,E,TEMP;
 
    for (t = 16; t <= 79; t++)
        ctx->W[t] = SHA_ROTL(ctx->W[t-3] ^ ctx->W[t-8] ^ ctx->W[t-14] ^ ctx->W[t-16], 1);
 
    A = ctx->H[0];
    B = ctx->H[1];
    C = ctx->H[2];
    D = ctx->H[3];
    E = ctx->H[4];
 
    for (t = 0; t <= 19; t++) {
        TEMP = (SHA_ROTL(A,5) + (((C^D)&B)^D)     + E + ctx->W[t] + 0x5a827999L) & 0xffffffffL;
        E = D; D = C; C = SHA_ROTL(B, 30); B = A; A = TEMP;
    }
    for (t = 20; t <= 39; t++) {