Initial Digest support. At least partly working. (334d78cd) · Commits · CYBER - Cyber Security / TS 103 523 MSP / TLMSP / TLMSP curl

lib/Makefile.am

+2 −1

Original line number	Diff line number	Diff line
		@@ -67,7 +67,8 @@ getpass.c netrc.c telnet.h getinfo.c getinfo.h transfer.c strequal.c \
		strequal.h easy.c security.h security.c krb4.c krb4.h memdebug.c \
		memdebug.h inet_ntoa_r.h http_chunks.c http_chunks.h strtok.c strtok.h \
		connect.c connect.h llist.c llist.h hash.c hash.h multi.c \
		content_encoding.c content_encoding.h share.c share.h
		content_encoding.c content_encoding.h share.c share.h http_digest.c \
		md5.c md5.h http_digest.h

		noinst_HEADERS = setup.h transfer.h

lib/http.c

+19 −10

Original line number	Diff line number	Diff line
		@@ -89,6 +89,7 @@
		#include "cookie.h"
		#include "strequal.h"
		#include "ssluse.h"
		#include "http_digest.h"

		#define _MPRINTF_REPLACE /* use our functions only */
		#include <curl/mprintf.h>
		@@ -627,6 +628,7 @@ CURLcode Curl_http(struct connectdata *conn)
		char *host = conn->name;
		const char te = ""; / tranfer-encoding */
		char *ptr;
		unsigned char *request;

		if(!conn->proto.http) {
		/* Only allocate this struct if we don't already have it! */
		@@ -648,6 +650,12 @@ CURLcode Curl_http(struct connectdata *conn)
		data->set.httpreq = HTTPREQ_PUT;
		}

		request = data->set.customrequest?data->set.customrequest:
		(data->set.no_body?"HEAD":
		((HTTPREQ_POST == data->set.httpreq) \|\|
		(HTTPREQ_POST_FORM == data->set.httpreq))?"POST":
		(HTTPREQ_PUT == data->set.httpreq)?"PUT":"GET");

		/* The User-Agent string has been built in url.c already, because it might
		have been used in the proxy connect, but if we have got a header with
		the user-agent string specified, we erase the previously made string
		@@ -657,7 +665,12 @@ CURLcode Curl_http(struct connectdata *conn)
		conn->allocptr.uagent=NULL;
		}

		if((conn->bits.user_passwd) && !checkheaders(data, "Authorization:")) {
		if(data->state.digest.nonce) {
		result = Curl_output_digest(conn, request, (unsigned char *)ppath);
		if(result)
		return result;
		}
		else if((conn->bits.user_passwd) && !checkheaders(data, "Authorization:")) {
		char *authorization;

		/* To prevent the user+password to get sent to other than the original
		@@ -902,7 +915,7 @@ CURLcode Curl_http(struct connectdata *conn)
		/* add the main request stuff */
		add_bufferf(req_buffer,
		"%s " /* GET/HEAD/POST/PUT */
		"%s HTTP/%s\r\n" /* path */
		"%s HTTP/%s\r\n" /* path + HTTP version */
		"%s" /* proxyuserpwd */
		"%s" /* userpwd */
		"%s" /* range */
		@@ -915,16 +928,12 @@ CURLcode Curl_http(struct connectdata *conn)
		"%s" /* referer */
		"%s",/* transfer-encoding */

		data->set.customrequest?data->set.customrequest:
		(data->set.no_body?"HEAD":
		((HTTPREQ_POST == data->set.httpreq) \|\|
		(HTTPREQ_POST_FORM == data->set.httpreq))?"POST":
		(HTTPREQ_PUT == data->set.httpreq)?"PUT":"GET"),
		ppath, httpstring,
		request,
		ppath,
		httpstring,
		(conn->bits.proxy_user_passwd &&
		conn->allocptr.proxyuserpwd)?conn->allocptr.proxyuserpwd:"",
		(conn->bits.user_passwd && conn->allocptr.userpwd)?
		conn->allocptr.userpwd:"",
		conn->allocptr.userpwd?conn->allocptr.userpwd:"",
		(conn->bits.use_range && conn->allocptr.rangeline)?
		conn->allocptr.rangeline:"",
		(data->set.useragent && *data->set.useragent && conn->allocptr.uagent)?

lib/http_digest.c

0 → 100644

+210 −0

Original line number	Diff line number	Diff line
		/***************************************************************************
		* _ _ ____ _
		* Project ___\| \| \| \| _ \\| \|
		* / __\| \| \| \| \|_) \| \|
		* \| (__\| \|_\| \| _ <\| \|___
		* \___\|\___/\|_\| \_\_____\|
		*
		* Copyright (C) 1998 - 2003, Daniel Stenberg, <daniel@haxx.se>, et al.
		*
		* This software is licensed as described in the file COPYING, which
		* you should have received as part of this distribution. The terms
		* are also available at http://curl.haxx.se/docs/copyright.html.
		*
		* You may opt to use, copy, modify, merge, publish, distribute and/or sell
		* copies of the Software, and permit persons to whom the Software is
		* furnished to do so, under the terms of the COPYING file.
		*
		* This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
		* KIND, either express or implied.
		*
		* $Id$
		***************************************************************************/
		#include "setup.h"

		#ifndef CURL_DISABLE_HTTP
		/* -- WIN32 approved -- */
		#include <stdio.h>
		#include <string.h>
		#include <stdarg.h>
		#include <stdlib.h>
		#include <ctype.h>

		#include "urldata.h"
		#include "sendf.h"
		#include "strequal.h"

		#include "md5.h"
		#include "http_digest.h"

		#define _MPRINTF_REPLACE /* use our functions only */
		#include <curl/mprintf.h>

		/* The last #include file should be: */
		#ifdef MALLOCDEBUG
		#include "memdebug.h"
		#endif

		/* Test example header:

		WWW-Authenticate: Digest realm="testrealm", nonce="1053604598"

		*/

		CURLdigest Curl_input_digest(struct connectdata *conn,
		char header) / rest of the www-authenticate:
		header */
		{
		bool more = TRUE;
		struct SessionHandle *data=conn->data;

		/* skip initial whitespaces */
		while(header && isspace((int)header))
		header++;

		if(checkprefix("Digest", header)) {
		header += strlen("Digest");

		data->state.digest.algo = CURLDIGESTALGO_MD5; /* default algorithm */

		while(more) {
		char value[32];
		char content[128];
		int totlen=0;

		while(header && isspace((int)header))
		header++;

		/* how big can these strings be? */
		if(2 == sscanf(header, "%31[^=]=\"%127[^\"]\"",
		value, content)) {
		if(strequal(value, "nonce")) {
		data->state.digest.nonce = strdup(content);
		}
		else if(strequal(value, "cnonce")) {
		data->state.digest.cnonce = strdup(content);
		}
		else if(strequal(value, "realm")) {
		data->state.digest.realm = strdup(content);
		}
		else if(strequal(value, "algorithm")) {
		if(strequal(content, "MD5-sess"))
		data->state.digest.algo = CURLDIGESTALGO_MD5SESS;
		/* else, remain using the default md5 */
		}
		else {
		/* unknown specifier, ignore it! */
		}
		totlen = strlen(value)+strlen(content)+3;
		}
		else
		break; /* we're done here */

		header += totlen;
		if(',' == *header)
		/* allow the list to be comma-separated */
		header++;
		}
		}
		else
		/* else not a digest, get out */
		return CURLDIGEST_NONE;

		return CURLDIGEST_FINE;
		}

		/* convert md5 chunk to RFC2617 (section 3.1.3) -suitable ascii string*/
		static void md5_to_ascii(unsigned char source, / 16 bytes */
		unsigned char dest) / 33 bytes */
		{
		int i;
		for(i=0; i<16; i++)
		sprintf((char )&dest[i2], "%02x", source[i]);
		}

		CURLcode Curl_output_digest(struct connectdata *conn,
		unsigned char *request,
		unsigned char *uripath)
		{
		/* We have a Digest setup for this, use it!
		Now, to get all the details for this sorted out, I must urge you dear friend
		to read up on the RFC2617 section 3.2.2, */
		unsigned char md5buf[16]; /* 16 bytes/128 bits */
		unsigned char ha1[33]; /* 32 digits and 1 zero byte */
		unsigned char ha2[33];
		unsigned char request_digest[33];
		char *md5this;

		struct SessionHandle *data = conn->data;

		/*
		if the algorithm is "MD5" or unspecified (which then defaults to MD5):

		A1 = unq(username-value) ":" unq(realm-value) ":" passwd

		if the algorithm is "MD5-sess" then:

		A1 = H( unq(username-value) ":" unq(realm-value) ":" passwd )
		":" unq(nonce-value) ":" unq(cnonce-value)
		*/
		if(data->state.digest.algo == CURLDIGESTALGO_MD5SESS) {
		md5this = aprintf("%s:%s:%s:%s:%s",
		data->state.user,
		data->state.digest.realm,
		data->state.passwd,
		data->state.digest.nonce,
		data->state.digest.cnonce);
		}
		else {
		md5this = aprintf("%s:%s:%s",
		data->state.user,
		data->state.digest.realm,
		data->state.passwd);
		}
		Curl_md5it(md5buf, md5this);
		free(md5this); /* free this again */
		md5_to_ascii(md5buf, ha1);

		/*
		A2 = Method ":" digest-uri-value

		(The "Method" value is the HTTP request method as specified in section
		5.1.1 of RFC 2616)
		*/

		md5this = aprintf("%s:%s", request, uripath);
		Curl_md5it(md5buf, md5this);
		free(md5this); /* free this again */
		md5_to_ascii(md5buf, ha2);

		md5this = aprintf("%s:%s:%s",
		ha1,
		data->state.digest.nonce,
		ha2);
		Curl_md5it(md5buf, md5this);
		free(md5this); /* free this again */
		md5_to_ascii(md5buf, request_digest);

		/* for test case 64 (snooped from a Mozilla 1.3a request)

		Authorization: Digest username="testuser", realm="testrealm", \
		nonce="1053604145", uri="/64", response="c55f7f30d83d774a3d2dcacf725abaca"
		*/

		conn->allocptr.userpwd =
		aprintf( "Authorization: Digest "
		"username=\"%s\", "
		"realm=\"%s\", "
		"nonce=\"%s\", "
		"uri=\"%s\", "
		"response=\"%s\"\r\n",
		data->state.user,
		data->state.digest.realm,
		data->state.digest.nonce,
		uripath, /* this is the PATH part of the URL */
		request_digest );

		return CURLE_OK;
		}

		#endif

lib/http_digest.h

0 → 100644

+43 −0

Original line number	Diff line number	Diff line
		/***************************************************************************
		* _ _ ____ _
		* Project ___\| \| \| \| _ \\| \|
		* / __\| \| \| \| \|_) \| \|
		* \| (__\| \|_\| \| _ <\| \|___
		* \___\|\___/\|_\| \_\_____\|
		*
		* Copyright (C) 1998 - 2003, Daniel Stenberg, <daniel@haxx.se>, et al.
		*
		* This software is licensed as described in the file COPYING, which
		* you should have received as part of this distribution. The terms
		* are also available at http://curl.haxx.se/docs/copyright.html.
		*
		* You may opt to use, copy, modify, merge, publish, distribute and/or sell
		* copies of the Software, and permit persons to whom the Software is
		* furnished to do so, under the terms of the COPYING file.
		*
		* This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
		* KIND, either express or implied.
		*
		* $Id$
		***************************************************************************/

		typedef enum {
		CURLDIGEST_NONE, /* not a digest */
		CURLDIGEST_BAD, /* a digest, but one we don't like */
		CURLDIGEST_FINE, /* a digest we act on */

		CURLDIGEST_LAST /* last entry in this enum, don't use */
		} CURLdigest;

		enum {
		CURLDIGESTALGO_MD5,
		CURLDIGESTALGO_MD5SESS
		};

		/* this is for digest header input */
		CURLdigest Curl_input_digest(struct connectdata conn, char header);

		/* this is for creating digest header output */
		CURLcode Curl_output_digest(struct connectdata *conn,
		unsigned char *request,
		unsigned char *uripath);

lib/md5.c

0 → 100644

+320 −0

Original line number	Diff line number	Diff line
		/* 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 <string.h>

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

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

		/* MD5 context. */
		struct md5_ctx {
		UINT4 state[4]; /* state (ABCD) */
		UINT4 count[2]; /* number of bits, modulo 2^64 (lsb first) */
		unsigned char buffer[64]; /* input buffer */
		};

		static void MD5Init(struct md5_ctx *);
		static void MD5Update(struct md5_ctx , unsigned char , unsigned int);
		static void MD5Final(unsigned char [16], struct md5_ctx *);

		/* 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(UINT4 [4], unsigned char [64]);
		static void Encode(unsigned char , UINT4 , unsigned int);
		static void Decode(UINT4 , unsigned char , unsigned int);

		#define MD5_memcpy(dst,src,len) memcpy(dst,src,len)
		#define MD5_memset(dst,val,len) memset(dst,val,len)

		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.
		*/
		static void MD5Init (context)
		struct 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.
		*/
		static void MD5Update (context, input, inputLen)
		struct 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((void )&context->buffer[index], (void )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((void )&context->buffer[index], (void )&input[i],
		inputLen-i);
		}

		/* MD5 finalization. Ends an MD5 message-digest operation, writing the
		the message digest and zeroizing the context.
		*/
		static void MD5Final (digest, context)
		unsigned char digest[16]; /* message digest */
		struct 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 ((void )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 ((void *)x, 0, sizeof (x));
		}

		/* Encodes input (UINT4) into output (unsigned char). Assumes len is
		a multiple of 4.
		*/
		static void Encode (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 (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);
		}

		void Curl_md5it(unsigned char outbuffer, / 16 bytes */
		unsigned char *input)
		{
		struct md5_ctx ctx;
		MD5Init(&ctx);
		MD5Update(&ctx, input, strlen((char *)input));
		MD5Final(outbuffer, &ctx);
		}