[thirdparty/glibc.git] / crypt / md5.c

/* Functions to compute MD5 message digest of files or memory blocks.
   according to the definition of MD5 in RFC 1321 from April 1992.
   Copyright (C) 1995, 1996, 1997, 1999, 2000 Free Software Foundation, Inc.
   This file is part of the GNU C Library.

   The GNU C 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.

   The GNU C 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 the GNU C Library; if not, write to the Free
   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
   02111-1307 USA.  */

/* Written by Ulrich Drepper <drepper@gnu.ai.mit.edu>, 1995.  */

#ifdef HAVE_CONFIG_H
# include <config.h>
#endif

#include <sys/types.h>

#if STDC_HEADERS || defined _LIBC
# include <stdlib.h>
# include <string.h>
#else
# ifndef HAVE_MEMCPY
#  define memcpy(d, s, n) bcopy ((s), (d), (n))
# endif
#endif

#include "md5.h"

#ifdef _LIBC
# include <endian.h>
# if __BYTE_ORDER == __BIG_ENDIAN
#  define WORDS_BIGENDIAN 1
# endif
/* We need to keep the namespace clean so define the MD5 function
   protected using leading __ .  */
# define md5_init_ctx __md5_init_ctx
# define md5_process_block __md5_process_block
# define md5_process_bytes __md5_process_bytes
# define md5_finish_ctx __md5_finish_ctx
# define md5_read_ctx __md5_read_ctx
# define md5_stream __md5_stream
# define md5_buffer __md5_buffer
#endif

#ifdef WORDS_BIGENDIAN
# define SWAP(n)							\
    (((n) << 24) | (((n) & 0xff00) << 8) | (((n) >> 8) & 0xff00) | ((n) >> 24))
#else
# define SWAP(n) (n)
#endif


/* This array contains the bytes used to pad the buffer to the next
   64-byte boundary.  (RFC 1321, 3.1: Step 1)  */
static const unsigned char fillbuf[64] = { 0x80, 0 /* , 0, 0, ...  */ };


/* Initialize structure containing state of computation.
   (RFC 1321, 3.3: Step 3)  */
void
md5_init_ctx (ctx)
     struct md5_ctx *ctx;
{
  ctx->A = 0x67452301;
  ctx->B = 0xefcdab89;
  ctx->C = 0x98badcfe;
  ctx->D = 0x10325476;

  ctx->total[0] = ctx->total[1] = 0;
  ctx->buflen = 0;
}

/* Put result from CTX in first 16 bytes following RESBUF.  The result
   must be in little endian byte order.

   IMPORTANT: On some systems it is required that RESBUF is correctly
   aligned for a 32 bits value.  */
void *
md5_read_ctx (ctx, resbuf)
     const struct md5_ctx *ctx;
     void *resbuf;
{
  ((md5_uint32 *) resbuf)[0] = SWAP (ctx->A);
  ((md5_uint32 *) resbuf)[1] = SWAP (ctx->B);
  ((md5_uint32 *) resbuf)[2] = SWAP (ctx->C);
  ((md5_uint32 *) resbuf)[3] = SWAP (ctx->D);

  return resbuf;
}

/* Process the remaining bytes in the internal buffer and the usual
   prolog according to the standard and write the result to RESBUF.

   IMPORTANT: On some systems it is required that RESBUF is correctly
   aligned for a 32 bits value.  */
void *
md5_finish_ctx (ctx, resbuf)
     struct md5_ctx *ctx;
     void *resbuf;
{
  /* Take yet unprocessed bytes into account.  */
  md5_uint32 bytes = ctx->buflen;
  size_t pad;

  /* Now count remaining bytes.  */
  ctx->total[0] += bytes;
  if (ctx->total[0] < bytes)
    ++ctx->total[1];

  pad = bytes >= 56 ? 64 + 56 - bytes : 56 - bytes;
  memcpy (&ctx->buffer[bytes], fillbuf, pad);

  /* Put the 64-bit file length in *bits* at the end of the buffer.  */
  *(md5_uint32 *) &ctx->buffer[bytes + pad] = SWAP (ctx->total[0] << 3);
  *(md5_uint32 *) &ctx->buffer[bytes + pad + 4] = SWAP ((ctx->total[1] << 3) |
							(ctx->total[0] >> 29));

  /* Process last bytes.  */
  md5_process_block (ctx->buffer, bytes + pad + 8, ctx);

  return md5_read_ctx (ctx, resbuf);
}

/* Compute MD5 message digest for bytes read from STREAM.  The
   resulting message digest number will be written into the 16 bytes
   beginning at RESBLOCK.  */
int
md5_stream (stream, resblock)
     FILE *stream;
     void *resblock;
{
  /* Important: BLOCKSIZE must be a multiple of 64.  */
#define BLOCKSIZE 4096
  struct md5_ctx ctx;
  char buffer[BLOCKSIZE + 72];
  size_t sum;

  /* Initialize the computation context.  */
  md5_init_ctx (&ctx);

  /* Iterate over full file contents.  */
  while (1)
    {
      /* We read the file in blocks of BLOCKSIZE bytes.  One call of the
	 computation function processes the whole buffer so that with the
	 next round of the loop another block can be read.  */
      size_t n;
      sum = 0;

      /* Read block.  Take care for partial reads.  */
      do
	{
	  n = fread (buffer + sum, 1, BLOCKSIZE - sum, stream);

	  sum += n;
	}
      while (sum < BLOCKSIZE && n != 0);
      if (n == 0 && ferror (stream))
        return 1;

      /* If end of file is reached, end the loop.  */
      if (n == 0)
	break;

      /* Process buffer with BLOCKSIZE bytes.  Note that
			BLOCKSIZE % 64 == 0
       */
      md5_process_block (buffer, BLOCKSIZE, &ctx);
    }

  /* Add the last bytes if necessary.  */
  if (sum > 0)
    md5_process_bytes (buffer, sum, &ctx);

  /* Construct result in desired memory.  */
  md5_finish_ctx (&ctx, resblock);
  return 0;
}

/* Compute MD5 message digest for LEN bytes beginning at BUFFER.  The
   result is always in little endian byte order, so that a byte-wise
   output yields to the wanted ASCII representation of the message
   digest.  */
void *
md5_buffer (buffer, len, resblock)
     const char *buffer;
     size_t len;
     void *resblock;
{
  struct md5_ctx ctx;

  /* Initialize the computation context.  */
  md5_init_ctx (&ctx);

  /* Process whole buffer but last len % 64 bytes.  */
  md5_process_bytes (buffer, len, &ctx);

  /* Put result in desired memory area.  */
  return md5_finish_ctx (&ctx, resblock);
}


void
md5_process_bytes (buffer, len, ctx)
     const void *buffer;
     size_t len;
     struct md5_ctx *ctx;
{
  //const void aligned_buffer = buffer;

  /* When we already have some bits in our internal buffer concatenate
     both inputs first.  */
  if (ctx->buflen != 0)
    {
      size_t left_over = ctx->buflen;
      size_t add = 128 - left_over > len ? len : 128 - left_over;

      /* Only put full words in the buffer.  */
      add -= add % __alignof__ (md5_uint32);

      memcpy (&ctx->buffer[left_over], buffer, add);
      ctx->buflen += add;

      if (ctx->buflen > 64)
	{
	  md5_process_block (ctx->buffer, ctx->buflen & ~63, ctx);

	  ctx->buflen &= 63;
	  /* The regions in the following copy operation cannot overlap.  */
	  memcpy (ctx->buffer, &ctx->buffer[(left_over + add) & ~63],
		  ctx->buflen);
	}

      buffer = (const char *) buffer + add;
      len -= add;
    }

  /* Process available complete blocks.  */
  if (len > 64)
    {
      md5_process_block (buffer, len & ~63, ctx);
      buffer = (const char *) buffer + (len & ~63);
      len &= 63;
    }

  /* Move remaining bytes in internal buffer.  */
  if (len > 0)
    {
      size_t left_over = ctx->buflen;

      memcpy (&ctx->buffer[left_over], buffer, len);
      left_over += len;
      if (left_over >= 64)
	{
	  md5_process_block (ctx->buffer, 64, ctx);
	  left_over -= 64;
	  memcpy (ctx->buffer, &ctx->buffer[64], left_over);
	}
      ctx->buflen = left_over;
    }
}


/* These are the four functions used in the four steps of the MD5 algorithm
   and defined in the RFC 1321.  The first function is a little bit optimized
   (as found in Colin Plumbs public domain implementation).  */
/* #define FF(b, c, d) ((b & c) | (~b & d)) */
#define FF(b, c, d) (d ^ (b & (c ^ d)))
#define FG(b, c, d) FF (d, b, c)
#define FH(b, c, d) (b ^ c ^ d)
#define FI(b, c, d) (c ^ (b | ~d))

/* Process LEN bytes of BUFFER, accumulating context into CTX.
   It is assumed that LEN % 64 == 0.  */

void
md5_process_block (buffer, len, ctx)
     const void *buffer;
     size_t len;
     struct md5_ctx *ctx;
{
  md5_uint32 correct_words[16];
  const md5_uint32 *words = buffer;
  size_t nwords = len / sizeof (md5_uint32);
  const md5_uint32 *endp = words + nwords;
  md5_uint32 A = ctx->A;
  md5_uint32 B = ctx->B;
  md5_uint32 C = ctx->C;
  md5_uint32 D = ctx->D;

  /* First increment the byte count.  RFC 1321 specifies the possible
     length of the file up to 2^64 bits.  Here we only compute the
     number of bytes.  Do a double word increment.  */
  ctx->total[0] += len;
  if (ctx->total[0] < len)
    ++ctx->total[1];

  /* Process all bytes in the buffer with 64 bytes in each round of
     the loop.  */
  while (words < endp)
    {
      md5_uint32 *cwp = correct_words;
      md5_uint32 A_save = A;
      md5_uint32 B_save = B;
      md5_uint32 C_save = C;
      md5_uint32 D_save = D;

      /* First round: using the given function, the context and a constant
	 the next context is computed.  Because the algorithms processing
	 unit is a 32-bit word and it is determined to work on words in
	 little endian byte order we perhaps have to change the byte order
	 before the computation.  To reduce the work for the next steps
	 we store the swapped words in the array CORRECT_WORDS.  */

#define OP(a, b, c, d, s, T)						\
      do								\
        {								\
	  a += FF (b, c, d) + (*cwp++ = SWAP (*words)) + T;		\
	  ++words;							\
	  CYCLIC (a, s);						\
	  a += b;							\
        }								\
      while (0)

      /* It is unfortunate that C does not provide an operator for
	 cyclic rotation.  Hope the C compiler is smart enough.  */
#define CYCLIC(w, s) (w = (w << s) | (w >> (32 - s)))

      /* Before we start, one word to the strange constants.
	 They are defined in RFC 1321 as

	 T[i] = (int) (4294967296.0 * fabs (sin (i))), i=1..64
       */

      /* Round 1.  */
      OP (A, B, C, D,  7, 0xd76aa478);
      OP (D, A, B, C, 12, 0xe8c7b756);
      OP (C, D, A, B, 17, 0x242070db);
      OP (B, C, D, A, 22, 0xc1bdceee);
      OP (A, B, C, D,  7, 0xf57c0faf);
      OP (D, A, B, C, 12, 0x4787c62a);
      OP (C, D, A, B, 17, 0xa8304613);
      OP (B, C, D, A, 22, 0xfd469501);
      OP (A, B, C, D,  7, 0x698098d8);
      OP (D, A, B, C, 12, 0x8b44f7af);
      OP (C, D, A, B, 17, 0xffff5bb1);
      OP (B, C, D, A, 22, 0x895cd7be);
      OP (A, B, C, D,  7, 0x6b901122);
      OP (D, A, B, C, 12, 0xfd987193);
      OP (C, D, A, B, 17, 0xa679438e);
      OP (B, C, D, A, 22, 0x49b40821);

      /* For the second to fourth round we have the possibly swapped words
	 in CORRECT_WORDS.  Redefine the macro to take an additional first
	 argument specifying the function to use.  */
#undef OP
#define OP(f, a, b, c, d, k, s, T)					\
      do 								\
	{								\
	  a += f (b, c, d) + correct_words[k] + T;			\
	  CYCLIC (a, s);						\
	  a += b;							\
	}								\
      while (0)

      /* Round 2.  */
      OP (FG, A, B, C, D,  1,  5, 0xf61e2562);
      OP (FG, D, A, B, C,  6,  9, 0xc040b340);
      OP (FG, C, D, A, B, 11, 14, 0x265e5a51);
      OP (FG, B, C, D, A,  0, 20, 0xe9b6c7aa);
      OP (FG, A, B, C, D,  5,  5, 0xd62f105d);
      OP (FG, D, A, B, C, 10,  9, 0x02441453);
      OP (FG, C, D, A, B, 15, 14, 0xd8a1e681);
      OP (FG, B, C, D, A,  4, 20, 0xe7d3fbc8);
      OP (FG, A, B, C, D,  9,  5, 0x21e1cde6);
      OP (FG, D, A, B, C, 14,  9, 0xc33707d6);
      OP (FG, C, D, A, B,  3, 14, 0xf4d50d87);
      OP (FG, B, C, D, A,  8, 20, 0x455a14ed);
      OP (FG, A, B, C, D, 13,  5, 0xa9e3e905);
      OP (FG, D, A, B, C,  2,  9, 0xfcefa3f8);
      OP (FG, C, D, A, B,  7, 14, 0x676f02d9);
      OP (FG, B, C, D, A, 12, 20, 0x8d2a4c8a);

      /* Round 3.  */
      OP (FH, A, B, C, D,  5,  4, 0xfffa3942);
      OP (FH, D, A, B, C,  8, 11, 0x8771f681);
      OP (FH, C, D, A, B, 11, 16, 0x6d9d6122);
      OP (FH, B, C, D, A, 14, 23, 0xfde5380c);
      OP (FH, A, B, C, D,  1,  4, 0xa4beea44);
      OP (FH, D, A, B, C,  4, 11, 0x4bdecfa9);
      OP (FH, C, D, A, B,  7, 16, 0xf6bb4b60);
      OP (FH, B, C, D, A, 10, 23, 0xbebfbc70);
      OP (FH, A, B, C, D, 13,  4, 0x289b7ec6);
      OP (FH, D, A, B, C,  0, 11, 0xeaa127fa);
      OP (FH, C, D, A, B,  3, 16, 0xd4ef3085);
      OP (FH, B, C, D, A,  6, 23, 0x04881d05);
      OP (FH, A, B, C, D,  9,  4, 0xd9d4d039);
      OP (FH, D, A, B, C, 12, 11, 0xe6db99e5);
      OP (FH, C, D, A, B, 15, 16, 0x1fa27cf8);
      OP (FH, B, C, D, A,  2, 23, 0xc4ac5665);

      /* Round 4.  */
      OP (FI, A, B, C, D,  0,  6, 0xf4292244);
      OP (FI, D, A, B, C,  7, 10, 0x432aff97);
      OP (FI, C, D, A, B, 14, 15, 0xab9423a7);
      OP (FI, B, C, D, A,  5, 21, 0xfc93a039);
      OP (FI, A, B, C, D, 12,  6, 0x655b59c3);
      OP (FI, D, A, B, C,  3, 10, 0x8f0ccc92);
      OP (FI, C, D, A, B, 10, 15, 0xffeff47d);
      OP (FI, B, C, D, A,  1, 21, 0x85845dd1);
      OP (FI, A, B, C, D,  8,  6, 0x6fa87e4f);
      OP (FI, D, A, B, C, 15, 10, 0xfe2ce6e0);
      OP (FI, C, D, A, B,  6, 15, 0xa3014314);
      OP (FI, B, C, D, A, 13, 21, 0x4e0811a1);
      OP (FI, A, B, C, D,  4,  6, 0xf7537e82);
      OP (FI, D, A, B, C, 11, 10, 0xbd3af235);
      OP (FI, C, D, A, B,  2, 15, 0x2ad7d2bb);
      OP (FI, B, C, D, A,  9, 21, 0xeb86d391);

      /* Add the starting values of the context.  */
      A += A_save;
      B += B_save;
      C += C_save;
      D += D_save;
    }

  /* Put checksum in context given as argument.  */
  ctx->A = A;
  ctx->B = B;
  ctx->C = C;
  ctx->D = D;
}
Commit	Line	Data
3248e3a3	1	/* Functions to compute MD5 message digest of files or memory blocks.
68dbb3a6	2	according to the definition of MD5 in RFC 1321 from April 1992.
3248e3a3	3	Copyright (C) 1995, 1996, 1997, 1999, 2000 Free Software Foundation, Inc.
68dbb3a6 UD	4	This file is part of the GNU C Library.
	5
	6	The GNU C Library is free software; you can redistribute it and/or
41bdb6e2 AJ	7	modify it under the terms of the GNU Lesser General Public
	8	License as published by the Free Software Foundation; either
	9	version 2.1 of the License, or (at your option) any later version.
68dbb3a6 UD	10
	11	The GNU C Library is distributed in the hope that it will be useful,
	12	but WITHOUT ANY WARRANTY; without even the implied warranty of
	13	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
41bdb6e2	14	Lesser General Public License for more details.
68dbb3a6	15
41bdb6e2 AJ	16	You should have received a copy of the GNU Lesser General Public
	17	License along with the GNU C Library; if not, write to the Free
	18	Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
	19	02111-1307 USA. */
68dbb3a6 UD	20
	21	/* Written by Ulrich Drepper <drepper@gnu.ai.mit.edu>, 1995. */
	22
	23	#ifdef HAVE_CONFIG_H
	24	# include <config.h>
	25	#endif
	26
	27	#include <sys/types.h>
	28
	29	#if STDC_HEADERS \|\| defined _LIBC
	30	# include <stdlib.h>
	31	# include <string.h>
	32	#else
	33	# ifndef HAVE_MEMCPY
	34	# define memcpy(d, s, n) bcopy ((s), (d), (n))
	35	# endif
	36	#endif
	37
	38	#include "md5.h"
	39
	40	#ifdef _LIBC
	41	# include <endian.h>
	42	# if __BYTE_ORDER == __BIG_ENDIAN
	43	# define WORDS_BIGENDIAN 1
	44	# endif
b13927da	45	/* We need to keep the namespace clean so define the MD5 function
a9b5d2ee	46	protected using leading __ . */
b13927da UD	47	# define md5_init_ctx __md5_init_ctx
	48	# define md5_process_block __md5_process_block
	49	# define md5_process_bytes __md5_process_bytes
	50	# define md5_finish_ctx __md5_finish_ctx
	51	# define md5_read_ctx __md5_read_ctx
	52	# define md5_stream __md5_stream
	53	# define md5_buffer __md5_buffer
68dbb3a6 UD	54	#endif
	55
	56	#ifdef WORDS_BIGENDIAN
	57	# define SWAP(n) \
	58	(((n) << 24) \| (((n) & 0xff00) << 8) \| (((n) >> 8) & 0xff00) \| ((n) >> 24))
	59	#else
	60	# define SWAP(n) (n)
	61	#endif
	62
	63
	64	/* This array contains the bytes used to pad the buffer to the next
	65	64-byte boundary. (RFC 1321, 3.1: Step 1) */
	66	static const unsigned char fillbuf[64] = { 0x80, 0 /* , 0, 0, ... */ };
	67
	68
	69	/* Initialize structure containing state of computation.
	70	(RFC 1321, 3.3: Step 3) */
	71	void
	72	md5_init_ctx (ctx)
	73	struct md5_ctx *ctx;
	74	{
	75	ctx->A = 0x67452301;
	76	ctx->B = 0xefcdab89;
	77	ctx->C = 0x98badcfe;
	78	ctx->D = 0x10325476;
	79
	80	ctx->total[0] = ctx->total[1] = 0;
	81	ctx->buflen = 0;
	82	}
	83
	84	/* Put result from CTX in first 16 bytes following RESBUF. The result
	85	must be in little endian byte order.
	86
	87	IMPORTANT: On some systems it is required that RESBUF is correctly
	88	aligned for a 32 bits value. */
	89	void *
	90	md5_read_ctx (ctx, resbuf)
	91	const struct md5_ctx *ctx;
	92	void *resbuf;
	93	{
	94	((md5_uint32 *) resbuf)[0] = SWAP (ctx->A);
	95	((md5_uint32 *) resbuf)[1] = SWAP (ctx->B);
	96	((md5_uint32 *) resbuf)[2] = SWAP (ctx->C);
	97	((md5_uint32 *) resbuf)[3] = SWAP (ctx->D);
	98
	99	return resbuf;
	100	}
	101
	102	/* Process the remaining bytes in the internal buffer and the usual
	103	prolog according to the standard and write the result to RESBUF.
	104
	105	IMPORTANT: On some systems it is required that RESBUF is correctly
	106	aligned for a 32 bits value. */
	107	void *
	108	md5_finish_ctx (ctx, resbuf)
	109	struct md5_ctx *ctx;
	110	void *resbuf;
	111	{
	112	/* Take yet unprocessed bytes into account. */
	113	md5_uint32 bytes = ctx->buflen;
	114	size_t pad;
	115
	116	/* Now count remaining bytes. */
	117	ctx->total[0] += bytes;
118	if (ctx->total[0] < bytes)
119	++ctx->total[1];
120
121	pad = bytes >= 56 ? 64 + 56 - bytes : 56 - bytes;
122	memcpy (&ctx->buffer[bytes], fillbuf, pad);
123
124	/* Put the 64-bit file length in bits at the end of the buffer. */
125	(md5_uint32 ) &ctx->buffer[bytes + pad] = SWAP (ctx->total[0] << 3);
126	(md5_uint32 ) &ctx->buffer[bytes + pad + 4] = SWAP ((ctx->total[1] << 3) \|
127	(ctx->total[0] >> 29));
128
129	/* Process last bytes. */
130	md5_process_block (ctx->buffer, bytes + pad + 8, ctx);
131
132	return md5_read_ctx (ctx, resbuf);
133	}
134
135	/* Compute MD5 message digest for bytes read from STREAM. The
136	resulting message digest number will be written into the 16 bytes
137	beginning at RESBLOCK. */
138	int
139	md5_stream (stream, resblock)
140	FILE *stream;
141	void *resblock;
142	{
143	/* Important: BLOCKSIZE must be a multiple of 64. */
144	#define BLOCKSIZE 4096
145	struct md5_ctx ctx;
146	char buffer[BLOCKSIZE + 72];
147	size_t sum;
148
149	/* Initialize the computation context. */
150	md5_init_ctx (&ctx);
151
152	/* Iterate over full file contents. */
153	while (1)
154	{
155	/* We read the file in blocks of BLOCKSIZE bytes. One call of the
156	computation function processes the whole buffer so that with the
157	next round of the loop another block can be read. */
158	size_t n;
159	sum = 0;
160
161	/* Read block. Take care for partial reads. */
162	do
163	{
164	n = fread (buffer + sum, 1, BLOCKSIZE - sum, stream);
165
166	sum += n;
167	}
168	while (sum < BLOCKSIZE && n != 0);
169	if (n == 0 && ferror (stream))
170	return 1;
171
172	/* If end of file is reached, end the loop. */
173	if (n == 0)
174	break;
175
176	/* Process buffer with BLOCKSIZE bytes. Note that
177	BLOCKSIZE % 64 == 0
178	*/
179	md5_process_block (buffer, BLOCKSIZE, &ctx);
180	}
181
182	/* Add the last bytes if necessary. */
183	if (sum > 0)
184	md5_process_bytes (buffer, sum, &ctx);
185
186	/* Construct result in desired memory. */
187	md5_finish_ctx (&ctx, resblock);
188	return 0;
189	}
190
191	/* Compute MD5 message digest for LEN bytes beginning at BUFFER. The
192	result is always in little endian byte order, so that a byte-wise
193	output yields to the wanted ASCII representation of the message
194	digest. */
195	void *
196	md5_buffer (buffer, len, resblock)
197	const char *buffer;
198	size_t len;
199	void *resblock;
200	{
201	struct md5_ctx ctx;
202
203	/* Initialize the computation context. */
204	md5_init_ctx (&ctx);
205
206	/* Process whole buffer but last len % 64 bytes. */
207	md5_process_bytes (buffer, len, &ctx);
208
209	/* Put result in desired memory area. */
210	return md5_finish_ctx (&ctx, resblock);
211	}
212
213
214	void
215	md5_process_bytes (buffer, len, ctx)
216	const void *buffer;
217	size_t len;
218	struct md5_ctx *ctx;
219	{
3248e3a3 UD	220	//const void aligned_buffer = buffer;
3248e3a3 UD	221
68dbb3a6 UD	222	/* When we already have some bits in our internal buffer concatenate
	223	both inputs first. */
	224	if (ctx->buflen != 0)
	225	{
	226	size_t left_over = ctx->buflen;
	227	size_t add = 128 - left_over > len ? len : 128 - left_over;
	228
3248e3a3 UD	229	/* Only put full words in the buffer. */
	230	add -= add % __alignof__ (md5_uint32);
	231
68dbb3a6 UD	232	memcpy (&ctx->buffer[left_over], buffer, add);
	233	ctx->buflen += add;
	234
3248e3a3	235	if (ctx->buflen > 64)
68dbb3a6	236	{
3248e3a3 UD	237	md5_process_block (ctx->buffer, ctx->buflen & ~63, ctx);
	238
	239	ctx->buflen &= 63;
68dbb3a6 UD	240	/* The regions in the following copy operation cannot overlap. */
68dbb3a6 UD	241	memcpy (ctx->buffer, &ctx->buffer[(left_over + add) & ~63],
3248e3a3	242	ctx->buflen);
68dbb3a6 UD	243	}
	244
	245	buffer = (const char *) buffer + add;
	246	len -= add;
	247	}
	248
	249	/* Process available complete blocks. */
	250	if (len > 64)
	251	{
	252	md5_process_block (buffer, len & ~63, ctx);
	253	buffer = (const char *) buffer + (len & ~63);
	254	len &= 63;
	255	}
	256
	257	/* Move remaining bytes in internal buffer. */
	258	if (len > 0)
	259	{
3248e3a3 UD	260	size_t left_over = ctx->buflen;
	261
	262	memcpy (&ctx->buffer[left_over], buffer, len);
	263	left_over += len;
	264	if (left_over >= 64)
	265	{
	266	md5_process_block (ctx->buffer, 64, ctx);
	267	left_over -= 64;
	268	memcpy (ctx->buffer, &ctx->buffer[64], left_over);
	269	}
	270	ctx->buflen = left_over;
68dbb3a6 UD	271	}
	272	}
	273
	274
	275	/* These are the four functions used in the four steps of the MD5 algorithm
	276	and defined in the RFC 1321. The first function is a little bit optimized
	277	(as found in Colin Plumbs public domain implementation). */
	278	/* #define FF(b, c, d) ((b & c) \| (~b & d)) */
	279	#define FF(b, c, d) (d ^ (b & (c ^ d)))
	280	#define FG(b, c, d) FF (d, b, c)
	281	#define FH(b, c, d) (b ^ c ^ d)
	282	#define FI(b, c, d) (c ^ (b \| ~d))
	283
	284	/* Process LEN bytes of BUFFER, accumulating context into CTX.
	285	It is assumed that LEN % 64 == 0. */
	286
	287	void
	288	md5_process_block (buffer, len, ctx)
	289	const void *buffer;
	290	size_t len;
	291	struct md5_ctx *ctx;
	292	{
	293	md5_uint32 correct_words[16];
	294	const md5_uint32 *words = buffer;
	295	size_t nwords = len / sizeof (md5_uint32);
	296	const md5_uint32 *endp = words + nwords;
	297	md5_uint32 A = ctx->A;
	298	md5_uint32 B = ctx->B;
	299	md5_uint32 C = ctx->C;
	300	md5_uint32 D = ctx->D;
	301
	302	/* First increment the byte count. RFC 1321 specifies the possible
	303	length of the file up to 2^64 bits. Here we only compute the
	304	number of bytes. Do a double word increment. */
	305	ctx->total[0] += len;
	306	if (ctx->total[0] < len)
	307	++ctx->total[1];
	308
	309	/* Process all bytes in the buffer with 64 bytes in each round of
	310	the loop. */
	311	while (words < endp)
	312	{
	313	md5_uint32 *cwp = correct_words;
	314	md5_uint32 A_save = A;
	315	md5_uint32 B_save = B;
	316	md5_uint32 C_save = C;
	317	md5_uint32 D_save = D;
	318
	319	/* First round: using the given function, the context and a constant
	320	the next context is computed. Because the algorithms processing
	321	unit is a 32-bit word and it is determined to work on words in
	322	little endian byte order we perhaps have to change the byte order
	323	before the computation. To reduce the work for the next steps
	324	we store the swapped words in the array CORRECT_WORDS. */
	325
	326	#define OP(a, b, c, d, s, T) \
	327	do \
	328	{ \
	329	a += FF (b, c, d) + (cwp++ = SWAP (words)) + T; \
	330	++words; \
	331	CYCLIC (a, s); \
	332	a += b; \
	333	} \
	334	while (0)
335
336	/* It is unfortunate that C does not provide an operator for
337	cyclic rotation. Hope the C compiler is smart enough. */
338	#define CYCLIC(w, s) (w = (w << s) \| (w >> (32 - s)))
339
340	/* Before we start, one word to the strange constants.
341	They are defined in RFC 1321 as
342
343	T[i] = (int) (4294967296.0 * fabs (sin (i))), i=1..64
344	*/
345
346	/* Round 1. */
347	OP (A, B, C, D, 7, 0xd76aa478);
348	OP (D, A, B, C, 12, 0xe8c7b756);
349	OP (C, D, A, B, 17, 0x242070db);
350	OP (B, C, D, A, 22, 0xc1bdceee);
351	OP (A, B, C, D, 7, 0xf57c0faf);
352	OP (D, A, B, C, 12, 0x4787c62a);
353	OP (C, D, A, B, 17, 0xa8304613);
354	OP (B, C, D, A, 22, 0xfd469501);
355	OP (A, B, C, D, 7, 0x698098d8);
356	OP (D, A, B, C, 12, 0x8b44f7af);
357	OP (C, D, A, B, 17, 0xffff5bb1);
358	OP (B, C, D, A, 22, 0x895cd7be);
359	OP (A, B, C, D, 7, 0x6b901122);
360	OP (D, A, B, C, 12, 0xfd987193);
361	OP (C, D, A, B, 17, 0xa679438e);
362	OP (B, C, D, A, 22, 0x49b40821);
363
364	/* For the second to fourth round we have the possibly swapped words
365	in CORRECT_WORDS. Redefine the macro to take an additional first
366	argument specifying the function to use. */
367	#undef OP
368	#define OP(f, a, b, c, d, k, s, T) \
369	do \
370	{ \
371	a += f (b, c, d) + correct_words[k] + T; \
372	CYCLIC (a, s); \
373	a += b; \
374	} \
375	while (0)
376
377	/* Round 2. */
378	OP (FG, A, B, C, D, 1, 5, 0xf61e2562);
379	OP (FG, D, A, B, C, 6, 9, 0xc040b340);
380	OP (FG, C, D, A, B, 11, 14, 0x265e5a51);
381	OP (FG, B, C, D, A, 0, 20, 0xe9b6c7aa);
382	OP (FG, A, B, C, D, 5, 5, 0xd62f105d);
383	OP (FG, D, A, B, C, 10, 9, 0x02441453);
384	OP (FG, C, D, A, B, 15, 14, 0xd8a1e681);
385	OP (FG, B, C, D, A, 4, 20, 0xe7d3fbc8);
386	OP (FG, A, B, C, D, 9, 5, 0x21e1cde6);
387	OP (FG, D, A, B, C, 14, 9, 0xc33707d6);
388	OP (FG, C, D, A, B, 3, 14, 0xf4d50d87);
389	OP (FG, B, C, D, A, 8, 20, 0x455a14ed);
390	OP (FG, A, B, C, D, 13, 5, 0xa9e3e905);
391	OP (FG, D, A, B, C, 2, 9, 0xfcefa3f8);
392	OP (FG, C, D, A, B, 7, 14, 0x676f02d9);
393	OP (FG, B, C, D, A, 12, 20, 0x8d2a4c8a);
394
395	/* Round 3. */
396	OP (FH, A, B, C, D, 5, 4, 0xfffa3942);
397	OP (FH, D, A, B, C, 8, 11, 0x8771f681);
398	OP (FH, C, D, A, B, 11, 16, 0x6d9d6122);
399	OP (FH, B, C, D, A, 14, 23, 0xfde5380c);
400	OP (FH, A, B, C, D, 1, 4, 0xa4beea44);
401	OP (FH, D, A, B, C, 4, 11, 0x4bdecfa9);
402	OP (FH, C, D, A, B, 7, 16, 0xf6bb4b60);
403	OP (FH, B, C, D, A, 10, 23, 0xbebfbc70);
404	OP (FH, A, B, C, D, 13, 4, 0x289b7ec6);
405	OP (FH, D, A, B, C, 0, 11, 0xeaa127fa);
406	OP (FH, C, D, A, B, 3, 16, 0xd4ef3085);
407	OP (FH, B, C, D, A, 6, 23, 0x04881d05);
408	OP (FH, A, B, C, D, 9, 4, 0xd9d4d039);
409	OP (FH, D, A, B, C, 12, 11, 0xe6db99e5);
410	OP (FH, C, D, A, B, 15, 16, 0x1fa27cf8);
411	OP (FH, B, C, D, A, 2, 23, 0xc4ac5665);
412
413	/* Round 4. */
414	OP (FI, A, B, C, D, 0, 6, 0xf4292244);
415	OP (FI, D, A, B, C, 7, 10, 0x432aff97);
416	OP (FI, C, D, A, B, 14, 15, 0xab9423a7);
417	OP (FI, B, C, D, A, 5, 21, 0xfc93a039);
418	OP (FI, A, B, C, D, 12, 6, 0x655b59c3);
419	OP (FI, D, A, B, C, 3, 10, 0x8f0ccc92);
420	OP (FI, C, D, A, B, 10, 15, 0xffeff47d);
421	OP (FI, B, C, D, A, 1, 21, 0x85845dd1);
422	OP (FI, A, B, C, D, 8, 6, 0x6fa87e4f);
423	OP (FI, D, A, B, C, 15, 10, 0xfe2ce6e0);
424	OP (FI, C, D, A, B, 6, 15, 0xa3014314);
425	OP (FI, B, C, D, A, 13, 21, 0x4e0811a1);
426	OP (FI, A, B, C, D, 4, 6, 0xf7537e82);
427	OP (FI, D, A, B, C, 11, 10, 0xbd3af235);
428	OP (FI, C, D, A, B, 2, 15, 0x2ad7d2bb);
429	OP (FI, B, C, D, A, 9, 21, 0xeb86d391);
430
431	/* Add the starting values of the context. */
432	A += A_save;
433	B += B_save;
434	C += C_save;
435	D += D_save;
436	}
437
438	/* Put checksum in context given as argument. */
439	ctx->A = A;
440	ctx->B = B;
441	ctx->C = C;
442	ctx->D = D;
443	}