/* 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 Software Foundation, Inc.
+ Copyright (C) 1995, 1996 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
- This program is free software; you can redistribute it and/or modify
- it under the terms of the GNU General Public License as published by
- the Free Software Foundation; either version 2, or (at your option)
- any later version.
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Library General Public License as
+ published by the Free Software Foundation; either version 2 of the
+ License, or (at your option) any later version.
- This program is distributed in the hope that it will be useful,
+ 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 General Public License for more details.
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Library General Public License for more details.
- You should have received a copy of the GNU General Public License
- along with this program; if not, write to the Free Software
- Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */
+ You should have received a copy of the GNU Library General Public
+ License along with the GNU C Library; see the file COPYING.LIB. 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>. */
+/* Written by Ulrich Drepper <drepper@gnu.ai.mit.edu>, 1995. */
#ifdef HAVE_CONFIG_H
# include <config.h>
#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
+#endif
+
#ifdef WORDS_BIGENDIAN
# define SWAP(n) \
(((n) << 24) | (((n) & 0xff00) << 8) | (((n) >> 8) & 0xff00) | ((n) >> 24))
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. */
+/* 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;
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. */
-void *
+int
md5_stream (stream, resblock)
FILE *stream;
void *resblock;
/* Important: BLOCKSIZE must be a multiple of 64. */
#define BLOCKSIZE 4096
struct md5_ctx ctx;
- md5_uint32 len[2];
char buffer[BLOCKSIZE + 72];
- size_t pad, sum;
+ size_t sum;
/* Initialize the computation context. */
md5_init_ctx (&ctx);
- len[0] = 0;
- len[1] = 0;
-
/* Iterate over full file contents. */
while (1)
{
/* Read block. Take care for partial reads. */
do
{
- n = fread (buffer, 1, BLOCKSIZE - sum, stream);
+ n = fread (buffer + sum, 1, BLOCKSIZE - sum, stream);
sum += n;
}
while (sum < BLOCKSIZE && n != 0);
-
- /* 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. */
- len[0] += sum;
- if (len[0] < sum)
- ++len[1];
+ if (n == 0 && ferror (stream))
+ return 1;
/* If end of file is reached, end the loop. */
if (n == 0)
md5_process_block (buffer, BLOCKSIZE, &ctx);
}
- /* We can copy 64 byte because the buffer is always big enough. FILLBUF
- contains the needed bits. */
- memcpy (&buffer[sum], fillbuf, 64);
-
- /* Compute amount of padding bytes needed. Alignment is done to
- (N + PAD) % 64 == 56
- There is always at least one byte padded. I.e. even the alignment
- is correctly aligned 64 padding bytes are added. */
- pad = sum & 63;
- pad = pad >= 56 ? 64 + 56 - pad : 56 - pad;
-
- /* Put the 64-bit file length in *bits* at the end of the buffer. */
- *(md5_uint32 *) &buffer[sum + pad] = SWAP (len[0] << 3);
- *(md5_uint32 *) &buffer[sum + pad + 4] = SWAP ((len[1] << 3) | (len[0] >> 29));
-
- /* Process last bytes. */
- md5_process_block (buffer, sum + pad + 8, &ctx);
+ /* Add the last bytes if necessary. */
+ if (sum > 0)
+ md5_process_bytes (buffer, sum, &ctx);
/* Construct result in desired memory. */
- return md5_read_ctx (&ctx, resblock);
+ md5_finish_ctx (&ctx, resblock);
+ return 0;
}
/* Compute MD5 message digest for LEN bytes beginning at BUFFER. The
void *resblock;
{
struct md5_ctx ctx;
- char restbuf[64 + 72];
- size_t blocks = len & ~63;
- size_t pad, rest;
/* Initialize the computation context. */
md5_init_ctx (&ctx);
/* Process whole buffer but last len % 64 bytes. */
- md5_process_block (buffer, blocks, &ctx);
+ md5_process_bytes (buffer, len, &ctx);
- /* REST bytes are not processed yet. */
- rest = len - blocks;
- /* Copy to own buffer. */
- memcpy (restbuf, &buffer[blocks], rest);
- /* Append needed fill bytes at end of buffer. We can copy 64 byte
- because the buffer is always big enough. */
- memcpy (&restbuf[rest], fillbuf, 64);
+ /* Put result in desired memory area. */
+ return md5_finish_ctx (&ctx, resblock);
+}
- /* PAD bytes are used for padding to correct alignment. Note that
- always at least one byte is padded. */
- pad = rest >= 56 ? 64 + 56 - rest : 56 - rest;
- /* Put length of buffer in *bits* in last eight bytes. */
- *(md5_uint32 *) &restbuf[rest + pad] = SWAP (len << 3);
- *(md5_uint32 *) &restbuf[rest + pad + 4] = SWAP (len >> 29);
+void
+md5_process_bytes (buffer, len, ctx)
+ const void *buffer;
+ size_t len;
+ struct md5_ctx *ctx;
+{
+ /* 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;
- /* Process last bytes. */
- md5_process_block (restbuf, rest + pad + 8, &ctx);
+ memcpy (&ctx->buffer[left_over], buffer, add);
+ ctx->buflen += add;
- /* Put result in desired memory area. */
- return md5_read_ctx (&ctx, resblock);
+ if (left_over + add > 64)
+ {
+ md5_process_block (ctx->buffer, (left_over + add) & ~63, ctx);
+ /* The regions in the following copy operation cannot overlap. */
+ memcpy (ctx->buffer, &ctx->buffer[(left_over + add) & ~63],
+ (left_over + add) & 63);
+ ctx->buflen = (left_over + add) & 63;
+ }
+
+ 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)
+ {
+ memcpy (ctx->buffer, buffer, len);
+ ctx->buflen = len;
+ }
}
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)
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