// *****************************************************************************
// kernel/src/md5.c
// author: Tony Fombaron aka Bob Le Gob - http://www.i-maginer.com
// version: 1.0
// date: April 17, 2008
//
// ref: http://www.ietf.org/rfc/rfc1321.txt
// *****************************************************************************



// This file isn't integrated in the project.
// It's an extract from above reference.
// It is here as a template, showing original source code.
// It's here too for the licenses.



//A.1 global.h *****************************************************************

/* GLOBAL.H - RSAREF types and constants
 */

/* PROTOTYPES should be set to one if and only if the compiler supports
  function argument prototyping.
	The following makes PROTOTYPES default to 0 if it has not already
  been defined with C compiler flags.
 */
#ifndef PROTOTYPES
#define PROTOTYPES 0
#endif

/* POINTER defines a generic pointer type */
typedef unsigned char *POINTER;

/* UINT2 defines a two byte word */
typedef unsigned short int UINT2;

/* UINT4 defines a four byte word */
typedef unsigned long int UINT4;

/* PROTO_LIST is defined depending on how PROTOTYPES is defined above.
If using PROTOTYPES, then PROTO_LIST returns the list, otherwise it
  returns an empty list.
 */
#if PROTOTYPES
#define PROTO_LIST(list) list
#else
#define PROTO_LIST(list) ()
#endif



//A.2 md5.h ********************************************************************

/* MD5.H - header file for MD5C.C
 */

/* Copyright (C) 1991-2, RSA Data Security, Inc. Created 1991. All
rights reserved.

License to copy and use this software is granted provided that it
is identified as the "RSA Data Security, Inc. MD5 Message-Digest
Algorithm" in all material mentioning or referencing this software
or this function.

License is also granted to make and use derivative works provided
that such works are identified as "derived from the RSA Data
Security, Inc. MD5 Message-Digest Algorithm" in all material
mentioning or referencing the derived work.

RSA Data Security, Inc. makes no representations concerning either
the merchantability of this software or the suitability of this
software for any particular purpose. It is provided "as is"
without express or implied warranty of any kind.

These notices must be retained in any copies of any part of this
documentation and/or software.
*/

// MD5 context.
typedef struct {
  UINT4 state[4];                                   /* state (ABCD) */
  UINT4 count[2];        /* number of bits, modulo 2^64 (lsb first) */
  unsigned char buffer[64];                         /* input buffer */
} MD5_CTX;

void MD5Init PROTO_LIST ((MD5_CTX *));
void MD5Update PROTO_LIST
  ((MD5_CTX *, unsigned char *, unsigned int));
void MD5Final PROTO_LIST ((unsigned char [16], MD5_CTX *));




//A.3 md5c.c *******************************************************************

/* MD5C.C - RSA Data Security, Inc., MD5 message-digest algorithm
 */

/* Copyright (C) 1991-2, RSA Data Security, Inc. Created 1991. All
rights reserved.

License to copy and use this software is granted provided that it
is identified as the "RSA Data Security, Inc. MD5 Message-Digest
Algorithm" in all material mentioning or referencing this software
or this function.

License is also granted to make and use derivative works provided
that such works are identified as "derived from the RSA Data
Security, Inc. MD5 Message-Digest Algorithm" in all material
mentioning or referencing the derived work.

RSA Data Security, Inc. makes no representations concerning either
the merchantability of this software or the suitability of this
software for any particular purpose. It is provided "as is"
without express or implied warranty of any kind.

These notices must be retained in any copies of any part of this
documentation and/or software.
 */

#include "global.h"
#include "md5.h"

// Constants for MD5Transform routine.
#define S11 7
#define S12 12
#define S13 17
#define S14 22
#define S21 5
#define S22 9
#define S23 14
#define S24 20
#define S31 4
#define S32 11
#define S33 16
#define S34 23
#define S41 6
#define S42 10
#define S43 15
#define S44 21


static void MD5Transform PROTO_LIST ((UINT4 [4], unsigned char [64]));
static void Encode PROTO_LIST ((unsigned char *, UINT4 *, unsigned int));
static void Decode PROTO_LIST ((UINT4 *, unsigned char *, unsigned int));
static void MD5_memcpy PROTO_LIST ((POINTER, POINTER, unsigned int));
static void MD5_memset PROTO_LIST ((POINTER, int, unsigned int));

static unsigned char PADDING[64] = {
  0x80, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
  0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
  0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
};


// F, G, H and I are basic MD5 functions.
#define F(x, y, z) (((x) & (y)) | ((~x) & (z)))
#define G(x, y, z) (((x) & (z)) | ((y) & (~z)))
#define H(x, y, z) ((x) ^ (y) ^ (z))
#define I(x, y, z) ((y) ^ ((x) | (~z)))


// ROTATE_LEFT rotates x left n bits.
#define ROTATE_LEFT(x, n) (((x) << (n)) | ((x) >> (32-(n))))


// FF, GG, HH, and II transformations for rounds 1, 2, 3, and 4.
// Rotation is separate from addition to prevent recomputation.
#define FF(a, b, c, d, x, s, ac) { \
 (a) += F ((b), (c), (d)) + (x) + (UINT4)(ac); \
 (a) = ROTATE_LEFT ((a), (s)); \
 (a) += (b); \
  }
#define GG(a, b, c, d, x, s, ac) { \
 (a) += G ((b), (c), (d)) + (x) + (UINT4)(ac); \
 (a) = ROTATE_LEFT ((a), (s)); \
 (a) += (b); \
  }
#define HH(a, b, c, d, x, s, ac) { \
 (a) += H ((b), (c), (d)) + (x) + (UINT4)(ac); \
 (a) = ROTATE_LEFT ((a), (s)); \
 (a) += (b); \
  }
#define II(a, b, c, d, x, s, ac) { \
 (a) += I ((b), (c), (d)) + (x) + (UINT4)(ac); \
 (a) = ROTATE_LEFT ((a), (s)); \
 (a) += (b); \
  }


// MD5 initialization. Begins an MD5 operation, writing a new context.
void MD5Init(context)
MD5_CTX *context;                                        /* context */
{
	context->count[0] = context->count[1] = 0;
	/* Load magic initialization constants */
	context->state[0] = 0x67452301;
	context->state[1] = 0xefcdab89;
	context->state[2] = 0x98badcfe;
	context->state[3] = 0x10325476;
}


// MD5 block update operation. Continues an MD5 message-digest
// operation, processing another message block, and updating the
// context.
void MD5Update(context, input, inputLen)
MD5_CTX *context;                                        /* context */
unsigned char *input;                                /* input block */
unsigned int inputLen;                     /* length of input block */
{
	unsigned int i, index, partLen;
	
	/* Compute number of bytes mod 64 */
	index = (unsigned int)((context->count[0] >> 3) & 0x3F);
	
	/* Update number of bits */
	if ((context->count[0] += ((UINT4)inputLen << 3)) < ((UINT4)inputLen << 3))
		context->count[1]++;
	context->count[1] += ((UINT4)inputLen >> 29);
	
	partLen = 64 - index;
	
	/* Transform as many times as possible */
	if (inputLen >= partLen) 
	{
		MD5_memcpy((POINTER)&context->buffer[index], (POINTER)input, partLen);
		MD5Transform(context->state, context->buffer);
		
		for (i = partLen; i + 63 < inputLen; i += 64)
			MD5Transform(context->state, &input[i]);
		
		index = 0;
	}
	else
		i = 0;
	
	/* Buffer remaining input */
	MD5_memcpy((POINTER)&context->buffer[index], (POINTER)&input[i], inputLen-i);
}


// MD5 finalization. Ends an MD5 message-digest operation, writing the message digest and zeroizing the context.
void MD5Final(digest, context)
unsigned char digest[16];                         /* message digest */
MD5_CTX *context;                                       /* context */
{
	unsigned char bits[8];
	unsigned int index, padLen;
	
	/* Save number of bits */
	Encode(bits, context->count, 8);
	
	/* Pad out to 56 mod 64 */
	index = (unsigned int)((context->count[0] >> 3) & 0x3f);
	padLen = (index < 56) ? (56 - index) : (120 - index);
	MD5Update (context, PADDING, padLen);
	
	/* Append length (before padding) */
	MD5Update(context, bits, 8);
	
	/* Store state in digest */
	Encode(digest, context->state, 16);
	
	/* Zeroize sensitive information */
	MD5_memset((POINTER)context, 0, sizeof (*context));
}


// MD5 basic transformation. Transforms state based on block.
static void MD5Transform(state, block)
UINT4 state[4];
unsigned char block[64];
{
	UINT4 a = state[0], b = state[1], c = state[2], d = state[3], x[16];
	
	Decode(x, block, 64);
	
	/* Round 1 */
	FF(a, b, c, d, x[ 0], S11, 0xd76aa478); /* 1 */
	FF(d, a, b, c, x[ 1], S12, 0xe8c7b756); /* 2 */
	FF(c, d, a, b, x[ 2], S13, 0x242070db); /* 3 */
	FF(b, c, d, a, x[ 3], S14, 0xc1bdceee); /* 4 */
	FF(a, b, c, d, x[ 4], S11, 0xf57c0faf); /* 5 */
	FF(d, a, b, c, x[ 5], S12, 0x4787c62a); /* 6 */
	FF(c, d, a, b, x[ 6], S13, 0xa8304613); /* 7 */
	FF(b, c, d, a, x[ 7], S14, 0xfd469501); /* 8 */
	FF(a, b, c, d, x[ 8], S11, 0x698098d8); /* 9 */
	FF(d, a, b, c, x[ 9], S12, 0x8b44f7af); /* 10 */
	FF(c, d, a, b, x[10], S13, 0xffff5bb1); /* 11 */
	FF(b, c, d, a, x[11], S14, 0x895cd7be); /* 12 */
	FF(a, b, c, d, x[12], S11, 0x6b901122); /* 13 */
	FF(d, a, b, c, x[13], S12, 0xfd987193); /* 14 */
	FF(c, d, a, b, x[14], S13, 0xa679438e); /* 15 */
	FF(b, c, d, a, x[15], S14, 0x49b40821); /* 16 */

	/* Round 2 */
	GG(a, b, c, d, x[ 1], S21, 0xf61e2562); /* 17 */
	GG(d, a, b, c, x[ 6], S22, 0xc040b340); /* 18 */
	GG(c, d, a, b, x[11], S23, 0x265e5a51); /* 19 */
	GG(b, c, d, a, x[ 0], S24, 0xe9b6c7aa); /* 20 */
	GG(a, b, c, d, x[ 5], S21, 0xd62f105d); /* 21 */
	GG(d, a, b, c, x[10], S22,  0x2441453); /* 22 */
	GG(c, d, a, b, x[15], S23, 0xd8a1e681); /* 23 */
	GG(b, c, d, a, x[ 4], S24, 0xe7d3fbc8); /* 24 */
	GG(a, b, c, d, x[ 9], S21, 0x21e1cde6); /* 25 */
	GG(d, a, b, c, x[14], S22, 0xc33707d6); /* 26 */
	GG(c, d, a, b, x[ 3], S23, 0xf4d50d87); /* 27 */
	GG(b, c, d, a, x[ 8], S24, 0x455a14ed); /* 28 */
	GG(a, b, c, d, x[13], S21, 0xa9e3e905); /* 29 */
	GG(d, a, b, c, x[ 2], S22, 0xfcefa3f8); /* 30 */
	GG(c, d, a, b, x[ 7], S23, 0x676f02d9); /* 31 */
	GG(b, c, d, a, x[12], S24, 0x8d2a4c8a); /* 32 */

	/* Round 3 */
	HH(a, b, c, d, x[ 5], S31, 0xfffa3942); /* 33 */
	HH(d, a, b, c, x[ 8], S32, 0x8771f681); /* 34 */
	HH(c, d, a, b, x[11], S33, 0x6d9d6122); /* 35 */
	HH(b, c, d, a, x[14], S34, 0xfde5380c); /* 36 */
	HH(a, b, c, d, x[ 1], S31, 0xa4beea44); /* 37 */
	HH(d, a, b, c, x[ 4], S32, 0x4bdecfa9); /* 38 */
	HH(c, d, a, b, x[ 7], S33, 0xf6bb4b60); /* 39 */
	HH(b, c, d, a, x[10], S34, 0xbebfbc70); /* 40 */
	HH(a, b, c, d, x[13], S31, 0x289b7ec6); /* 41 */
	HH(d, a, b, c, x[ 0], S32, 0xeaa127fa); /* 42 */
	HH(c, d, a, b, x[ 3], S33, 0xd4ef3085); /* 43 */
	HH(b, c, d, a, x[ 6], S34,  0x4881d05); /* 44 */
	HH(a, b, c, d, x[ 9], S31, 0xd9d4d039); /* 45 */
	HH(d, a, b, c, x[12], S32, 0xe6db99e5); /* 46 */
	HH(c, d, a, b, x[15], S33, 0x1fa27cf8); /* 47 */
	HH(b, c, d, a, x[ 2], S34, 0xc4ac5665); /* 48 */

	/* Round 4 */
	II(a, b, c, d, x[ 0], S41, 0xf4292244); /* 49 */
	II(d, a, b, c, x[ 7], S42, 0x432aff97); /* 50 */
	II(c, d, a, b, x[14], S43, 0xab9423a7); /* 51 */
	II(b, c, d, a, x[ 5], S44, 0xfc93a039); /* 52 */
	II(a, b, c, d, x[12], S41, 0x655b59c3); /* 53 */
	II(d, a, b, c, x[ 3], S42, 0x8f0ccc92); /* 54 */
	II(c, d, a, b, x[10], S43, 0xffeff47d); /* 55 */
	II(b, c, d, a, x[ 1], S44, 0x85845dd1); /* 56 */
	II(a, b, c, d, x[ 8], S41, 0x6fa87e4f); /* 57 */
	II(d, a, b, c, x[15], S42, 0xfe2ce6e0); /* 58 */
	II(c, d, a, b, x[ 6], S43, 0xa3014314); /* 59 */
	II(b, c, d, a, x[13], S44, 0x4e0811a1); /* 60 */
	II(a, b, c, d, x[ 4], S41, 0xf7537e82); /* 61 */
	II(d, a, b, c, x[11], S42, 0xbd3af235); /* 62 */
	II(c, d, a, b, x[ 2], S43, 0x2ad7d2bb); /* 63 */
	II(b, c, d, a, x[ 9], S44, 0xeb86d391); /* 64 */

	state[0] += a;
	state[1] += b;
	state[2] += c;
	state[3] += d;
	
	/* Zeroize sensitive information */
	MD5_memset((POINTER)x, 0, sizeof (x));
}


// Encodes input (UINT4) into output (unsigned char). Assumes len is a multiple of 4.
static void Encode(output, input, len)
unsigned char *output;
UINT4 *input;
unsigned int len;
{
	unsigned int i, j;
	
	for (i = 0, j = 0; j < len; i++, j += 4) 
	{
		output[j] = (unsigned char)(input[i] & 0xff);
		output[j+1] = (unsigned char)((input[i] >> 8) & 0xff);
		output[j+2] = (unsigned char)((input[i] >> 16) & 0xff);
		output[j+3] = (unsigned char)((input[i] >> 24) & 0xff);
	}
}


// Decodes input (unsigned char) into output (UINT4). Assumes len is a multiple of 4.
static void Decode(output, input, len)
UINT4 *output;
unsigned char *input;
unsigned int len;
{
  unsigned int i, j;

	for (i = 0, j = 0; j < len; i++, j += 4)
		output[i] = ((UINT4)input[j]) | (((UINT4)input[j+1]) << 8) | (((UINT4)input[j+2]) << 16) | (((UINT4)input[j+3]) << 24);
}


// Note: Replace "for loop" with standard memcpy if possible.
static void MD5_memcpy(output, input, len)
POINTER output;
POINTER input;
unsigned int len;
{
	unsigned int i;
	
	for (i = 0; i < len; i++)
		output[i] = input[i];
}


// Note: Replace "for loop" with standard memset if possible.
static void MD5_memset(output, value, len)
POINTER output;
int value;
unsigned int len;
{
	unsigned int i;
	
	for (i = 0; i < len; i++)
		((char *)output)[i] = (char)value;
}




// A.4 mddriver.c **************************************************************

/* MDDRIVER.C - test driver for MD2, MD4 and MD5
 */

/* Copyright (C) 1990-2, RSA Data Security, Inc. Created 1990. All
rights reserved.

RSA Data Security, Inc. makes no representations concerning either
the merchantability of this software or the suitability of this
software for any particular purpose. It is provided "as is"
without express or implied warranty of any kind.

These notices must be retained in any copies of any part of this
documentation and/or software.
 */

/* The following makes MD default to MD5 if it has not already been
  defined with C compiler flags.
 */
#ifndef MD
#define MD MD5
#endif

#include <stdio.h>
#include <time.h>
#include <string.h>
#include "global.h"
#if MD == 2
#include "md2.h"
#endif
#if MD == 4
#include "md4.h"
#endif
#if MD == 5
#include "md5.h"
#endif

// Length of test block, number of test blocks.
#define TEST_BLOCK_LEN 1000
#define TEST_BLOCK_COUNT 1000

static void MDString PROTO_LIST ((char *));
static void MDTimeTrial PROTO_LIST ((void));
static void MDTestSuite PROTO_LIST ((void));
static void MDFile PROTO_LIST ((char *));
static void MDFilter PROTO_LIST ((void));
static void MDPrint PROTO_LIST ((unsigned char [16]));

#if MD == 2
#define MD_CTX MD2_CTX
#define MDInit MD2Init
#define MDUpdate MD2Update
#define MDFinal MD2Final
#endif
#if MD == 4
#define MD_CTX MD4_CTX
#define MDInit MD4Init
#define MDUpdate MD4Update
#define MDFinal MD4Final
#endif
#if MD == 5
#define MD_CTX MD5_CTX
#define MDInit MD5Init
#define MDUpdate MD5Update
#define MDFinal MD5Final
#endif

// Main driver.
// Arguments (may be any combination):
//  -sstring - digests string
//  -t       - runs time trial
//  -x       - runs test script
//  filename - digests file
//  (none)   - digests standard input
 int main (argc, argv)
int argc;
char *argv[];
{
	int i;
	
	if (argc > 1)
		for (i = 1; i < argc; i++)
		 if (argv[i][0] == '-' && argv[i][1] == 's')
		   MDString (argv[i] + 2);
		 else if (strcmp (argv[i], "-t") == 0)
		   MDTimeTrial ();
		 else if (strcmp (argv[i], "-x") == 0)
		   MDTestSuite ();
		 else
		   MDFile (argv[i]);
	else
		MDFilter ();
	
	return (0);
}


// Digests a string and prints the result.
static void MDString(string)
char *string;
{
	MD_CTX context;
	unsigned char digest[16];
	unsigned int len = strlen (string);
	
	MDInit(&context);
	MDUpdate(&context, string, len);
	MDFinal(digest, &context);
	
	printf("MD%d (\"%s\") = ", MD, string);
	MDPrint(digest);
	printf("\n");
}


// Measures the time to digest TEST_BLOCK_COUNT TEST_BLOCK_LEN-byte blocks.
static void MDTimeTrial()
{
	MD_CTX context;
	time_t endTime, startTime;
	unsigned char block[TEST_BLOCK_LEN], digest[16];
	unsigned int i;
	
	printf("MD%d time trial. Digesting %d %d-byte blocks ...", MD, TEST_BLOCK_LEN, TEST_BLOCK_COUNT);
	
	/* Initialize block */
	for (i = 0; i < TEST_BLOCK_LEN; i++)
		block[i] = (unsigned char)(i & 0xff);
	
	/* Start timer */
	time(&startTime);

	/* Digest blocks */
	MDInit(&context);
	for (i = 0; i < TEST_BLOCK_COUNT; i++)
		MDUpdate(&context, block, TEST_BLOCK_LEN);
	MDFinal(digest, &context);
	
	/* Stop timer */
	time(&endTime);
	
	printf(" done\n");
	printf("Digest = ");
	MDPrint(digest);
	printf("\nTime = %ld seconds\n", (long)(endTime-startTime));
	printf("Speed = %ld bytes/second\n", (long)TEST_BLOCK_LEN * (long)TEST_BLOCK_COUNT/(endTime-startTime));
}


// Digests a reference suite of strings and prints the results.
static void MDTestSuite()
{
  printf("MD%d test suite:\n", MD);

  MDString("");
  MDString("a");
  MDString("abc");
  MDString("message digest");
  MDString("abcdefghijklmnopqrstuvwxyz");
  MDString("ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789");
  MDString("12345678901234567890123456789012345678901234567890123456789012345678901234567890");
}


// Digests a file and prints the result.
static void MDFile(filename)
char *filename;
{
	FILE *file;
	MD_CTX context;
	int len;
	unsigned char buffer[1024], digest[16];
	
	if ((file = fopen(filename, "rb")) == NULL)
		printf("%s can't be opened\n", filename);
	else 
	{
		MDInit(&context);
		while (len = fread (buffer, 1, 1024, file))
			MDUpdate(&context, buffer, len);
		MDFinal(digest, &context);
		
		fclose(file);
		
		printf("MD%d (%s) = ", MD, filename);
		MDPrint(digest);
		printf("\n");
	}
}


// Digests the standard input and prints the result.
static void MDFilter()
{
	MD_CTX context;
	int len;
	unsigned char buffer[16], digest[16];
	
	MDInit(&context);
	while (len = fread(buffer, 1, 16, stdin))
		MDUpdate(&context, buffer, len);
	MDFinal(digest, &context);
	
	MDPrint(digest);
	printf("\n");
}


// Prints a message digest in hexadecimal.
static void MDPrint(digest)
unsigned char digest[16];
{
	unsigned int i;
	
	for (i = 0; i < 16; i++)
		printf("%02x", digest[i]);
}



/*

MD5 test suite:
MD5 ("") = d41d8cd98f00b204e9800998ecf8427e
MD5 ("a") = 0cc175b9c0f1b6a831c399e269772661
MD5 ("abc") = 900150983cd24fb0d6963f7d28e17f72
MD5 ("message digest") = f96b697d7cb7938d525a2f31aaf161d0
MD5 ("abcdefghijklmnopqrstuvwxyz") = c3fcd3d76192e4007dfb496cca67e13b
MD5 ("ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789") =
d174ab98d277d9f5a5611c2c9f419d9f
MD5 ("123456789012345678901234567890123456789012345678901234567890123456
78901234567890") = 57edf4a22be3c955ac49da2e2107b67a

*/