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/* MD5C.C - RSA Data Security, Inc., MD5 message-digest algorithm |
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*/ |
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|
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/* Copyright (C) 1991-2, RSA Data Security, Inc. Created 1991. All |
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rights reserved. |
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|
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License to copy and use this software is granted provided that it |
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is identified as the "RSA Data Security, Inc. MD5 Message-Digest |
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Algorithm" in all material mentioning or referencing this software |
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or this function. |
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|
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License is also granted to make and use derivative works provided |
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that such works are identified as "derived from the RSA Data |
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Security, Inc. MD5 Message-Digest Algorithm" in all material |
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mentioning or referencing the derived work. |
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|
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RSA Data Security, Inc. makes no representations concerning either |
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the merchantability of this software or the suitability of this |
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software for any particular purpose. It is provided "as is" |
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without express or implied warranty of any kind. |
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|
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These notices must be retained in any copies of any part of this |
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documentation and/or software. |
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*/ |
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|
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#include "md5.h" |
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|
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/* Constants for MD5Transform routine. |
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*/ |
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|
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#define S11 7 |
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#define S12 12 |
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#define S13 17 |
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#define S14 22 |
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#define S21 5 |
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#define S22 9 |
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#define S23 14 |
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#define S24 20 |
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#define S31 4 |
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#define S32 11 |
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#define S33 16 |
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#define S34 23 |
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#define S41 6 |
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#define S42 10 |
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#define S43 15 |
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#define S44 21 |
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|
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static void MD5Transform PROTO_LIST ((UINT4 [4], unsigned char [64])); |
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static void Encode PROTO_LIST |
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((unsigned char *, UINT4 *, unsigned int)); |
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static void Decode PROTO_LIST |
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((UINT4 *, unsigned char *, unsigned int)); |
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static void MD5_memcpy PROTO_LIST ((POINTER, POINTER, unsigned int)); |
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static void MD5_memset PROTO_LIST ((POINTER, int, unsigned int)); |
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|
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static unsigned char PADDING[64] = { |
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0x80, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, |
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0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, |
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0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 |
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}; |
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|
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/* F, G, H and I are basic MD5 functions. |
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*/ |
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#define F(x, y, z) (((x) & (y)) | ((~x) & (z))) |
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#define G(x, y, z) (((x) & (z)) | ((y) & (~z))) |
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#define H(x, y, z) ((x) ^ (y) ^ (z)) |
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#define I(x, y, z) ((y) ^ ((x) | (~z))) |
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|
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/* ROTATE_LEFT rotates x left n bits. |
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*/ |
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#define ROTATE_LEFT(x, n) (((x) << (n)) | ((x) >> (32-(n)))) |
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|
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/* FF, GG, HH, and II transformations for rounds 1, 2, 3, and 4. |
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Rotation is separate from addition to prevent recomputation. |
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*/ |
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#define FF(a, b, c, d, x, s, ac) { \ |
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(a) += F ((b), (c), (d)) + (x) + (UINT4)(ac); \ |
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(a) = ROTATE_LEFT ((a), (s)); \ |
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(a) += (b); \ |
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} |
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#define GG(a, b, c, d, x, s, ac) { \ |
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(a) += G ((b), (c), (d)) + (x) + (UINT4)(ac); \ |
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(a) = ROTATE_LEFT ((a), (s)); \ |
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(a) += (b); \ |
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} |
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#define HH(a, b, c, d, x, s, ac) { \ |
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(a) += H ((b), (c), (d)) + (x) + (UINT4)(ac); \ |
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(a) = ROTATE_LEFT ((a), (s)); \ |
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(a) += (b); \ |
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} |
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#define II(a, b, c, d, x, s, ac) { \ |
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(a) += I ((b), (c), (d)) + (x) + (UINT4)(ac); \ |
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(a) = ROTATE_LEFT ((a), (s)); \ |
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(a) += (b); \ |
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} |
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|
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/* MD5 initialization. Begins an MD5 operation, writing a new context. |
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*/ |
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void MD5Init (MD5_CTX *context) |
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/* context */ |
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{ |
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context->count[0] = context->count[1] = 0; |
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/* Load magic initialization constants. |
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*/ |
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context->state[0] = 0x67452301; |
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context->state[1] = 0xefcdab89; |
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context->state[2] = 0x98badcfe; |
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context->state[3] = 0x10325476; |
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} |
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|
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/* MD5 block update operation. Continues an MD5 message-digest |
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operation, processing another message block, and updating the |
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context. |
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*/ |
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void MD5Update (MD5_CTX *context, unsigned char *input, unsigned int inputLen) |
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/* context */ |
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/* input block */ |
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/* length of input block */ |
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{ |
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unsigned int i, index, partLen; |
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|
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/* Compute number of bytes mod 64 */ |
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index = (unsigned int)((context->count[0] >> 3) & 0x3F); |
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|
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/* Update number of bits */ |
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if ((context->count[0] += ((UINT4)inputLen << 3)) |
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< ((UINT4)inputLen << 3)) |
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context->count[1]++; |
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context->count[1] += ((UINT4)inputLen >> 29); |
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|
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partLen = 64 - index; |
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|
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/* Transform as many times as possible. |
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*/ |
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if (inputLen >= partLen) { |
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MD5_memcpy |
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((POINTER)&context->buffer[index], (POINTER)input, partLen); |
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MD5Transform (context->state, context->buffer); |
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|
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for (i = partLen; i + 63 < inputLen; i += 64) |
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MD5Transform (context->state, &input[i]); |
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|
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index = 0; |
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} |
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else |
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i = 0; |
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|
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/* Buffer remaining input */ |
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MD5_memcpy |
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((POINTER)&context->buffer[index], (POINTER)&input[i], |
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inputLen-i); |
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} |
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|
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/* MD5 finalization. Ends an MD5 message-digest operation, writing the |
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the message digest and zeroizing the context. |
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*/ |
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void MD5Final (unsigned char *digest, MD5_CTX *context) |
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/* message digest */ |
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/* context */ |
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{ |
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unsigned char bits[8]; |
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unsigned int index, padLen; |
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|
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/* Save number of bits */ |
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Encode (bits, context->count, 8); |
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|
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/* Pad out to 56 mod 64. |
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*/ |
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index = (unsigned int)((context->count[0] >> 3) & 0x3f); |
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padLen = (index < 56) ? (56 - index) : (120 - index); |
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MD5Update (context, PADDING, padLen); |
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|
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/* Append length (before padding) */ |
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MD5Update (context, bits, 8); |
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|
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/* Store state in digest */ |
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Encode (digest, context->state, 16); |
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|
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/* Zeroize sensitive information. |
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*/ |
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MD5_memset ((POINTER)context, 0, sizeof (*context)); |
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} |
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|
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/* MD5 basic transformation. Transforms state based on block. |
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*/ |
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static void MD5Transform (UINT4 *state, unsigned char *block) |
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{ |
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UINT4 a = state[0], b = state[1], c = state[2], d = state[3], x[16]; |
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|
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Decode (x, block, 64); |
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|
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/* Round 1 */ |
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FF (a, b, c, d, x[ 0], S11, 0xd76aa478); /* 1 */ |
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FF (d, a, b, c, x[ 1], S12, 0xe8c7b756); /* 2 */ |
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FF (c, d, a, b, x[ 2], S13, 0x242070db); /* 3 */ |
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FF (b, c, d, a, x[ 3], S14, 0xc1bdceee); /* 4 */ |
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FF (a, b, c, d, x[ 4], S11, 0xf57c0faf); /* 5 */ |
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FF (d, a, b, c, x[ 5], S12, 0x4787c62a); /* 6 */ |
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FF (c, d, a, b, x[ 6], S13, 0xa8304613); /* 7 */ |
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FF (b, c, d, a, x[ 7], S14, 0xfd469501); /* 8 */ |
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FF (a, b, c, d, x[ 8], S11, 0x698098d8); /* 9 */ |
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FF (d, a, b, c, x[ 9], S12, 0x8b44f7af); /* 10 */ |
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FF (c, d, a, b, x[10], S13, 0xffff5bb1); /* 11 */ |
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FF (b, c, d, a, x[11], S14, 0x895cd7be); /* 12 */ |
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FF (a, b, c, d, x[12], S11, 0x6b901122); /* 13 */ |
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FF (d, a, b, c, x[13], S12, 0xfd987193); /* 14 */ |
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FF (c, d, a, b, x[14], S13, 0xa679438e); /* 15 */ |
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FF (b, c, d, a, x[15], S14, 0x49b40821); /* 16 */ |
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|
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/* Round 2 */ |
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GG (a, b, c, d, x[ 1], S21, 0xf61e2562); /* 17 */ |
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GG (d, a, b, c, x[ 6], S22, 0xc040b340); /* 18 */ |
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GG (c, d, a, b, x[11], S23, 0x265e5a51); /* 19 */ |
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GG (b, c, d, a, x[ 0], S24, 0xe9b6c7aa); /* 20 */ |
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GG (a, b, c, d, x[ 5], S21, 0xd62f105d); /* 21 */ |
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GG (d, a, b, c, x[10], S22, 0x2441453); /* 22 */ |
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GG (c, d, a, b, x[15], S23, 0xd8a1e681); /* 23 */ |
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GG (b, c, d, a, x[ 4], S24, 0xe7d3fbc8); /* 24 */ |
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GG (a, b, c, d, x[ 9], S21, 0x21e1cde6); /* 25 */ |
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GG (d, a, b, c, x[14], S22, 0xc33707d6); /* 26 */ |
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GG (c, d, a, b, x[ 3], S23, 0xf4d50d87); /* 27 */ |
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GG (b, c, d, a, x[ 8], S24, 0x455a14ed); /* 28 */ |
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GG (a, b, c, d, x[13], S21, 0xa9e3e905); /* 29 */ |
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GG (d, a, b, c, x[ 2], S22, 0xfcefa3f8); /* 30 */ |
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GG (c, d, a, b, x[ 7], S23, 0x676f02d9); /* 31 */ |
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GG (b, c, d, a, x[12], S24, 0x8d2a4c8a); /* 32 */ |
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|
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/* Round 3 */ |
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HH (a, b, c, d, x[ 5], S31, 0xfffa3942); /* 33 */ |
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HH (d, a, b, c, x[ 8], S32, 0x8771f681); /* 34 */ |
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HH (c, d, a, b, x[11], S33, 0x6d9d6122); /* 35 */ |
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HH (b, c, d, a, x[14], S34, 0xfde5380c); /* 36 */ |
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HH (a, b, c, d, x[ 1], S31, 0xa4beea44); /* 37 */ |
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HH (d, a, b, c, x[ 4], S32, 0x4bdecfa9); /* 38 */ |
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HH (c, d, a, b, x[ 7], S33, 0xf6bb4b60); /* 39 */ |
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HH (b, c, d, a, x[10], S34, 0xbebfbc70); /* 40 */ |
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HH (a, b, c, d, x[13], S31, 0x289b7ec6); /* 41 */ |
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HH (d, a, b, c, x[ 0], S32, 0xeaa127fa); /* 42 */ |
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HH (c, d, a, b, x[ 3], S33, 0xd4ef3085); /* 43 */ |
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HH (b, c, d, a, x[ 6], S34, 0x4881d05); /* 44 */ |
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HH (a, b, c, d, x[ 9], S31, 0xd9d4d039); /* 45 */ |
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HH (d, a, b, c, x[12], S32, 0xe6db99e5); /* 46 */ |
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HH (c, d, a, b, x[15], S33, 0x1fa27cf8); /* 47 */ |
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HH (b, c, d, a, x[ 2], S34, 0xc4ac5665); /* 48 */ |
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|
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/* Round 4 */ |
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II (a, b, c, d, x[ 0], S41, 0xf4292244); /* 49 */ |
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II (d, a, b, c, x[ 7], S42, 0x432aff97); /* 50 */ |
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II (c, d, a, b, x[14], S43, 0xab9423a7); /* 51 */ |
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II (b, c, d, a, x[ 5], S44, 0xfc93a039); /* 52 */ |
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II (a, b, c, d, x[12], S41, 0x655b59c3); /* 53 */ |
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II (d, a, b, c, x[ 3], S42, 0x8f0ccc92); /* 54 */ |
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II (c, d, a, b, x[10], S43, 0xffeff47d); /* 55 */ |
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II (b, c, d, a, x[ 1], S44, 0x85845dd1); /* 56 */ |
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II (a, b, c, d, x[ 8], S41, 0x6fa87e4f); /* 57 */ |
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II (d, a, b, c, x[15], S42, 0xfe2ce6e0); /* 58 */ |
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II (c, d, a, b, x[ 6], S43, 0xa3014314); /* 59 */ |
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II (b, c, d, a, x[13], S44, 0x4e0811a1); /* 60 */ |
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II (a, b, c, d, x[ 4], S41, 0xf7537e82); /* 61 */ |
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II (d, a, b, c, x[11], S42, 0xbd3af235); /* 62 */ |
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II (c, d, a, b, x[ 2], S43, 0x2ad7d2bb); /* 63 */ |
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II (b, c, d, a, x[ 9], S44, 0xeb86d391); /* 64 */ |
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|
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state[0] += a; |
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state[1] += b; |
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state[2] += c; |
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state[3] += d; |
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|
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/* Zeroize sensitive information. |
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*/ |
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MD5_memset ((POINTER)x, 0, sizeof (x)); |
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} |
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|
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/* Encodes input (UINT4) into output (unsigned char). Assumes len is |
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a multiple of 4. |
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*/ |
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static void Encode (unsigned char *output, UINT4 *input, unsigned int len) |
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{ |
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unsigned int i, j; |
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|
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for (i = 0, j = 0; j < len; i++, j += 4) { |
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output[j] = (unsigned char)(input[i] & 0xff); |
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output[j+1] = (unsigned char)((input[i] >> 8) & 0xff); |
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output[j+2] = (unsigned char)((input[i] >> 16) & 0xff); |
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output[j+3] = (unsigned char)((input[i] >> 24) & 0xff); |
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} |
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} |
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|
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/* Decodes input (unsigned char) into output (UINT4). Assumes len is |
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a multiple of 4. |
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*/ |
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static void Decode (UINT4 *output, unsigned char *input, unsigned int len) |
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{ |
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unsigned int i, j; |
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|
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for (i = 0, j = 0; j < len; i++, j += 4) |
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output[i] = ((UINT4)input[j]) | (((UINT4)input[j+1]) << 8) | |
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(((UINT4)input[j+2]) << 16) | (((UINT4)input[j+3]) << 24); |
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} |
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|
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/* Note: Replace "for loop" with standard memcpy if possible. |
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*/ |
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|
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static void MD5_memcpy (POINTER output, POINTER input, unsigned int len) |
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{ |
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unsigned int i; |
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|
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for (i = 0; i < len; i++) |
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output[i] = input[i]; |
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} |
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|
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/* Note: Replace "for loop" with standard memset if possible. |
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*/ |
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static void MD5_memset (POINTER output, int value, unsigned int len) |
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{ |
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unsigned int i; |
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|
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for (i = 0; i < len; i++) |
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((char *)output)[i] = (char)value; |
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} |