#ifndef AUTH_MD5_H #define AUTH_MD5_H /* ========================================================================== ** * * MD5.h * * Copyright: * Copyright (C) 2003, 2004 by Christopher R. Hertel * * Email: crh@ubiqx.mn.org * * Modified for use with MPlayer, detailed CVS changelog at * http://www.mplayerhq.hu/cgi-bin/cvsweb.cgi/main/ * $Id$ * * -------------------------------------------------------------------------- ** * * Description: * Implements the MD5 hash algorithm, as described in RFC 1321. * * -------------------------------------------------------------------------- ** * * License: * * This library is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation; either * version 2.1 of the License, or (at your option) any later version. * * This library is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with this library; if not, write to the Free Software * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA * * -------------------------------------------------------------------------- ** * * Notes: * * None of this will make any sense unless you're studying RFC 1321 as you * read the code. * * MD5 is described in RFC 1321. * The MD*4* algorithm is described in RFC 1320 (that's 1321 - 1). * MD5 is very similar to MD4, but not quite similar enough to justify * putting the two into a single module. Besides, I wanted to add a few * extra functions to this one to expand its usability. * * There are three primary motivations for this particular implementation. * 1) Programmer's pride. I wanted to be able to say I'd done it, and I * wanted to learn from the experience. * 2) Portability. I wanted an implementation that I knew to be portable * to a reasonable number platforms. In particular, the algorithm is * designed with little-endian platforms in mind, but I wanted an * endian-agnostic implementation. * 3) Compactness. While not an overriding goal, I thought it worth-while * to see if I could reduce the overall size of the result. This is in * keeping with my hopes that this library will be suitable for use in * some embedded environments. * Beyond that, cleanliness and clarity are always worth pursuing. * * As mentioned above, the code really only makes sense if you are familiar * with the MD5 algorithm or are using RFC 1321 as a guide. This code is * quirky, however, so you'll want to be reading carefully. * * Yeah...most of the comments are cut-and-paste from my MD4 implementation. * * -------------------------------------------------------------------------- ** * * References: * IETF RFC 1321: The MD5 Message-Digest Algorithm * Ron Rivest. IETF, April, 1992 * * ========================================================================== ** */ /* #include "auth_common.h" This was in the original. */ #include /* This was not... */ /* -------------------------------------------------------------------------- ** * Typedefs: */ typedef unsigned char uchar; /* Added uchar typedef to keep as close to the original as possible. */ typedef struct { uint32_t len; uint32_t ABCD[4]; int b_used; uchar block[64]; } auth_md5Ctx; /* -------------------------------------------------------------------------- ** * Functions: */ auth_md5Ctx *auth_md5InitCtx( auth_md5Ctx *ctx ); /* ------------------------------------------------------------------------ ** * Initialize an MD5 context. * * Input: ctx - A pointer to the MD5 context structure to be initialized. * Contexts are typically created thusly: * ctx = (auth_md5Ctx *)malloc( sizeof(auth_md5Ctx) ); * * Output: A pointer to the initialized context (same as ). * * Notes: The purpose of the context is to make it possible to generate * an MD5 Message Digest in stages, rather than having to pass a * single large block to a single MD5 function. The context * structure keeps track of various bits of state information. * * Once the context is initialized, the blocks of message data * are passed to the function. Once the * final bit of data has been handed to the * context can be closed out by calling , * which also calculates the final MD5 result. * * Don't forget to free an allocated context structure when * you've finished using it. * * See Also: , * * ------------------------------------------------------------------------ ** */ auth_md5Ctx *auth_md5SumCtx( auth_md5Ctx *ctx, const uchar *src, const int len ); /* ------------------------------------------------------------------------ ** * Build an MD5 Message Digest within the given context. * * Input: ctx - Pointer to the context in which the MD5 sum is being * built. * src - A chunk of source data. This will be used to drive * the MD5 algorithm. * len - The number of bytes in . * * Output: A pointer to the updated context (same as ). * * See Also: , , * * ------------------------------------------------------------------------ ** */ auth_md5Ctx *auth_md5CloseCtx( auth_md5Ctx *ctx, uchar *dst ); /* ------------------------------------------------------------------------ ** * Close an MD5 Message Digest context and generate the final MD5 sum. * * Input: ctx - Pointer to the context in which the MD5 sum is being * built. * dst - A pointer to at least 16 bytes of memory, which will * receive the finished MD5 sum. * * Output: A pointer to the closed context (same as ). * You might use this to free a malloc'd context structure. :) * * Notes: The context () is returned in an undefined state. * It must be re-initialized before re-use. * * See Also: , * * ------------------------------------------------------------------------ ** */ uchar *auth_md5Sum( uchar *dst, const uchar *src, const int len ); /* ------------------------------------------------------------------------ ** * Compute an MD5 message digest. * * Input: dst - Destination buffer into which the result will be written. * Must be 16 bytes, minimum. * src - Source data block to be MD5'd. * len - The length, in bytes, of the source block. * (Note that the length is given in bytes, not bits.) * * Output: A pointer to , which will contain the calculated 16-byte * MD5 message digest. * * Notes: This function is a shortcut. It takes a single input block. * For more drawn-out operations, see . * * This function is interface-compatible with the * function in the MD4 module. * * The MD5 algorithm is designed to work on data with an * arbitrary *bit* length. Most implementations, this one * included, handle the input data in byte-sized chunks. * * The MD5 algorithm does much of its work using four-byte * words, and so can be tuned for speed based on the endian-ness * of the host. This implementation is intended to be * endian-neutral, which may make it a teeny bit slower than * others. ...maybe. * * See Also: * * ------------------------------------------------------------------------ ** */ /* ========================================================================== */ #endif /* AUTH_MD5_H */