X-Git-Url: http://git.sameswireless.fr/l2tpns.git/blobdiff_plain/7aa420ce9f2c55049b061c7df836ccc990303ebf..e7c9a1993778e9ac375d7f956dda7c3c802a83a5:/md5.c diff --git a/md5.c b/md5.c index 1911dc5..184a876 100644 --- a/md5.c +++ b/md5.c @@ -1,351 +1,272 @@ -/* MD5C.C - RSA Data Security, Inc., MD5 message-digest algorithm - */ - -char const *cvs_id_md5 = "$Id: md5.c,v 1.2 2004-06-28 02:43:13 fred_nerk Exp $"; - -/* 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. +/* + * This is an OpenSSL-compatible implementation of the RSA Data Security, + * Inc. MD5 Message-Digest Algorithm. + * + * Written by Solar Designer in 2001, and placed + * in the public domain. There's absolutely no warranty. + * + * This differs from Colin Plumb's older public domain implementation in + * that no 32-bit integer data type is required, there's no compile-time + * endianness configuration, and the function prototypes match OpenSSL's. + * The primary goals are portability and ease of use. + * + * This implementation is meant to be fast, but not as fast as possible. + * Some known optimizations are not included to reduce source code size + * and avoid compile-time configuration. */ +#include #include "md5.h" -/* Constants for MD5Transform routine. +/* + * The basic MD5 functions. + * + * F is optimized compared to its RFC 1321 definition just like in Colin + * Plumb's implementation. */ +#define F(x, y, z) ((z) ^ ((x) & ((y) ^ (z)))) +#define G(x, y, z) ((y) ^ ((z) & ((x) ^ (y)))) +#define H(x, y, z) ((x) ^ (y) ^ (z)) +#define I(x, y, z) ((y) ^ ((x) | ~(z))) -#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. +/* + * The MD5 transformation for all four rounds. */ -#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 STEP(f, a, b, c, d, x, t, s) \ + (a) += f((b), (c), (d)) + (x) + (t); \ + (a) = (((a) << (s)) | (((a) & 0xffffffff) >> (32 - (s)))); \ + (a) += (b); + +/* + * SET reads 4 input bytes in little-endian byte order and stores them + * in a properly aligned word in host byte order. + * + * The check for little-endian architectures which tolerate unaligned + * memory accesses is just an optimization. Nothing will break if it + * doesn't work. */ -#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. +#if defined(__i386__) || defined(__vax__) +# define SET(n) (*(MD5_u32plus *)&ptr[(n) * 4]) +# define GET(n) SET(n) +#else +# define SET(n) \ + (ctx->block[(n)] = \ + (MD5_u32plus)ptr[(n) * 4] | \ + ((MD5_u32plus)ptr[(n) * 4 + 1] << 8) | \ + ((MD5_u32plus)ptr[(n) * 4 + 2] << 16) | \ + ((MD5_u32plus)ptr[(n) * 4 + 3] << 24)) +# define GET(n) \ + (ctx->block[(n)]) +#endif + +/* + * This processes one or more 64-byte data blocks, but does NOT update + * the bit counters. There're no alignment requirements. */ -void -MD5Init(context) - MD5_CTX *context; /* context */ +static void *body(MD5_CTX *ctx, void *data, unsigned long size) { - 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; + unsigned char *ptr; + MD5_u32plus a, b, c, d; + MD5_u32plus saved_a, saved_b, saved_c, saved_d; + + ptr = data; + + a = ctx->a; + b = ctx->b; + c = ctx->c; + d = ctx->d; + + do { + saved_a = a; + saved_b = b; + saved_c = c; + saved_d = d; + + /* Round 1 */ + STEP(F, a, b, c, d, SET(0), 0xd76aa478, 7) + STEP(F, d, a, b, c, SET(1), 0xe8c7b756, 12) + STEP(F, c, d, a, b, SET(2), 0x242070db, 17) + STEP(F, b, c, d, a, SET(3), 0xc1bdceee, 22) + STEP(F, a, b, c, d, SET(4), 0xf57c0faf, 7) + STEP(F, d, a, b, c, SET(5), 0x4787c62a, 12) + STEP(F, c, d, a, b, SET(6), 0xa8304613, 17) + STEP(F, b, c, d, a, SET(7), 0xfd469501, 22) + STEP(F, a, b, c, d, SET(8), 0x698098d8, 7) + STEP(F, d, a, b, c, SET(9), 0x8b44f7af, 12) + STEP(F, c, d, a, b, SET(10), 0xffff5bb1, 17) + STEP(F, b, c, d, a, SET(11), 0x895cd7be, 22) + STEP(F, a, b, c, d, SET(12), 0x6b901122, 7) + STEP(F, d, a, b, c, SET(13), 0xfd987193, 12) + STEP(F, c, d, a, b, SET(14), 0xa679438e, 17) + STEP(F, b, c, d, a, SET(15), 0x49b40821, 22) + + /* Round 2 */ + STEP(G, a, b, c, d, GET(1), 0xf61e2562, 5) + STEP(G, d, a, b, c, GET(6), 0xc040b340, 9) + STEP(G, c, d, a, b, GET(11), 0x265e5a51, 14) + STEP(G, b, c, d, a, GET(0), 0xe9b6c7aa, 20) + STEP(G, a, b, c, d, GET(5), 0xd62f105d, 5) + STEP(G, d, a, b, c, GET(10), 0x02441453, 9) + STEP(G, c, d, a, b, GET(15), 0xd8a1e681, 14) + STEP(G, b, c, d, a, GET(4), 0xe7d3fbc8, 20) + STEP(G, a, b, c, d, GET(9), 0x21e1cde6, 5) + STEP(G, d, a, b, c, GET(14), 0xc33707d6, 9) + STEP(G, c, d, a, b, GET(3), 0xf4d50d87, 14) + STEP(G, b, c, d, a, GET(8), 0x455a14ed, 20) + STEP(G, a, b, c, d, GET(13), 0xa9e3e905, 5) + STEP(G, d, a, b, c, GET(2), 0xfcefa3f8, 9) + STEP(G, c, d, a, b, GET(7), 0x676f02d9, 14) + STEP(G, b, c, d, a, GET(12), 0x8d2a4c8a, 20) + + /* Round 3 */ + STEP(H, a, b, c, d, GET(5), 0xfffa3942, 4) + STEP(H, d, a, b, c, GET(8), 0x8771f681, 11) + STEP(H, c, d, a, b, GET(11), 0x6d9d6122, 16) + STEP(H, b, c, d, a, GET(14), 0xfde5380c, 23) + STEP(H, a, b, c, d, GET(1), 0xa4beea44, 4) + STEP(H, d, a, b, c, GET(4), 0x4bdecfa9, 11) + STEP(H, c, d, a, b, GET(7), 0xf6bb4b60, 16) + STEP(H, b, c, d, a, GET(10), 0xbebfbc70, 23) + STEP(H, a, b, c, d, GET(13), 0x289b7ec6, 4) + STEP(H, d, a, b, c, GET(0), 0xeaa127fa, 11) + STEP(H, c, d, a, b, GET(3), 0xd4ef3085, 16) + STEP(H, b, c, d, a, GET(6), 0x04881d05, 23) + STEP(H, a, b, c, d, GET(9), 0xd9d4d039, 4) + STEP(H, d, a, b, c, GET(12), 0xe6db99e5, 11) + STEP(H, c, d, a, b, GET(15), 0x1fa27cf8, 16) + STEP(H, b, c, d, a, GET(2), 0xc4ac5665, 23) + + /* Round 4 */ + STEP(I, a, b, c, d, GET(0), 0xf4292244, 6) + STEP(I, d, a, b, c, GET(7), 0x432aff97, 10) + STEP(I, c, d, a, b, GET(14), 0xab9423a7, 15) + STEP(I, b, c, d, a, GET(5), 0xfc93a039, 21) + STEP(I, a, b, c, d, GET(12), 0x655b59c3, 6) + STEP(I, d, a, b, c, GET(3), 0x8f0ccc92, 10) + STEP(I, c, d, a, b, GET(10), 0xffeff47d, 15) + STEP(I, b, c, d, a, GET(1), 0x85845dd1, 21) + STEP(I, a, b, c, d, GET(8), 0x6fa87e4f, 6) + STEP(I, d, a, b, c, GET(15), 0xfe2ce6e0, 10) + STEP(I, c, d, a, b, GET(6), 0xa3014314, 15) + STEP(I, b, c, d, a, GET(13), 0x4e0811a1, 21) + STEP(I, a, b, c, d, GET(4), 0xf7537e82, 6) + STEP(I, d, a, b, c, GET(11), 0xbd3af235, 10) + STEP(I, c, d, a, b, GET(2), 0x2ad7d2bb, 15) + STEP(I, b, c, d, a, GET(9), 0xeb86d391, 21) + + a += saved_a; + b += saved_b; + c += saved_c; + d += saved_d; + + ptr += MD5_BLOCK_SZ; + } while (size -= MD5_BLOCK_SZ); + + ctx->a = a; + ctx->b = b; + ctx->c = c; + ctx->d = d; + + return ptr; } -/* 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 */ +void MD5_Init(MD5_CTX *ctx) { - 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); + ctx->a = 0x67452301; + ctx->b = 0xefcdab89; + ctx->c = 0x98badcfe; + ctx->d = 0x10325476; - 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); + ctx->lo = 0; + ctx->hi = 0; } -/* MD5 finalization. Ends an MD5 message-digest operation, writing the - the message digest and zeroizing the context. - */ -void -MD5Final(digest, context) - unsigned char digest[16]; /* message digest */ - MD5_CTX *context; /* context */ +void MD5_Update(MD5_CTX *ctx, void *data, unsigned long size) { - unsigned char bits[8]; - unsigned int index, - padLen; + MD5_u32plus saved_lo; + unsigned long used, free; - /* Save number of bits */ - Encode(bits, context->count, 8); + saved_lo = ctx->lo; + if ((ctx->lo = (saved_lo + size) & 0x1fffffff) < saved_lo) + ctx->hi++; - /* 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); + ctx->hi += size >> 29; - /* Append length (before padding) */ - MD5Update(context, bits, 8); + used = saved_lo & 0x3f; - /* Store state in digest */ - Encode(digest, context->state, 16); + if (used) + { + free = MD5_BLOCK_SZ - used; - /* Zeroize sensitive information. - */ - MD5_memset((POINTER) context, 0, sizeof(*context)); -} + if (size < free) + { + memcpy(&ctx->buffer[used], data, size); + return; + } -/* 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; + memcpy(&ctx->buffer[used], data, free); + data = (unsigned char *)data + free; + size -= free; + body(ctx, ctx->buffer, MD5_BLOCK_SZ); + } - 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); -} + if (size >= MD5_BLOCK_SZ) + { + data = body(ctx, data, size & ~(unsigned long)0x3f); + size &= 0x3f; + } -/* 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]; + memcpy(ctx->buffer, data, size); } -/* Note: Replace "for loop" with standard memset if possible. - */ -static void -MD5_memset(output, value, len) - POINTER output; - int value; - unsigned int len; +void MD5_Final(unsigned char *result, MD5_CTX *ctx) { - unsigned int i; - - for (i = 0; i < len; i++) - ((char *) output)[i] = (char) value; + unsigned long used, free; + + used = ctx->lo & 0x3f; + + ctx->buffer[used++] = 0x80; + + free = MD5_BLOCK_SZ - used; + + if (free < 8) + { + memset(&ctx->buffer[used], 0, free); + body(ctx, ctx->buffer, MD5_BLOCK_SZ); + used = 0; + free = MD5_BLOCK_SZ; + } + + memset(&ctx->buffer[used], 0, free - 8); + + ctx->lo <<= 3; + ctx->buffer[56] = ctx->lo; + ctx->buffer[57] = ctx->lo >> 8; + ctx->buffer[58] = ctx->lo >> 16; + ctx->buffer[59] = ctx->lo >> 24; + ctx->buffer[60] = ctx->hi; + ctx->buffer[61] = ctx->hi >> 8; + ctx->buffer[62] = ctx->hi >> 16; + ctx->buffer[63] = ctx->hi >> 24; + + body(ctx, ctx->buffer, MD5_BLOCK_SZ); + + result[0] = ctx->a; + result[1] = ctx->a >> 8; + result[2] = ctx->a >> 16; + result[3] = ctx->a >> 24; + result[4] = ctx->b; + result[5] = ctx->b >> 8; + result[6] = ctx->b >> 16; + result[7] = ctx->b >> 24; + result[8] = ctx->c; + result[9] = ctx->c >> 8; + result[10] = ctx->c >> 16; + result[11] = ctx->c >> 24; + result[12] = ctx->d; + result[13] = ctx->d >> 8; + result[14] = ctx->d >> 16; + result[15] = ctx->d >> 24; + + memset(ctx, 0, sizeof(*ctx)); }