[libdvdnav-devel] [PATCH] src/md5: Replace the MD5 implementation
Andrew Clayton
andrew at digital-domain.net
Wed Nov 5 22:36:37 CET 2014
With GCC 4.8.3 on x86_64 Fedora 20 we get the following warnings from
src/md5.c
src/md5.c: In function 'md5_finish_ctx':
src/md5.c:102:3: warning: dereferencing type-punned pointer will
break strict-aliasing rules [-Wstrict-aliasing]
*(md5_uint32 *) &ctx->buffer[bytes + pad] = SWAP (ctx->total[0] <<
3);
^
src/md5.c:103:3: warning: dereferencing type-punned pointer will
break strict-aliasing rules [-Wstrict-aliasing]
*(md5_uint32 *) &ctx->buffer[bytes + pad + 4] = SWAP
((ctx->total[1] << 3) |
^
Rather than trying to fix this, Jean-Baptiste Kempf suggested it would
be better to replace this old implementation with something newer such
as the one used in VLC. So, this is what this does.
We take src/misc/md5.c as src/md5.c and include/vlc_md5.h as src/md5.h
md5.c had little changed in it, just some #include changes, I also had
to remove the restrict keyword from the AddMD5() function definition as
this is a C99 thing. This shouldn't really make much difference in this
usage.
md5.h had the VLC_API macro usage removed and I removed the psz_md5_hash
function as it's not used.
Finally DVDDiscID() in src/dvd_reader.c was changed to make use of this
new implementation. I tested this with the following program
/*
* gcc -O2 -Wall -o dvddiscid dvddiscid.c -ldvdread
*/
#include <stdio.h>
#include <dvdread/dvd_reader.h>
int main(void)
{
int i;
dvd_reader_t *dvd;
unsigned char id[16];
dvd = DVDOpen("/dev/sr0");
DVDDiscID(dvd, id);
DVDClose(dvd);
for (i = 0; i < 16; i++)
printf("%.2x", id[i]);
printf("\n");
return 0;
}
and get the same MD5 before and after this change.
$ ./dvddiscid
a02f30eb3e76e624b766ec0248757901
$ LD_LIBRARY_PATH=/opt/libdvdread/lib ./dvddiscid
a02f30eb3e76e624b766ec0248757901
Signed-off-by: Andrew Clayton <andrew at digital-domain.net>
---
src/dvd_reader.c | 9 +-
src/md5.c | 748 +++++++++++++++++++++++++------------------------------
src/md5.h | 207 ++++-----------
3 files changed, 397 insertions(+), 567 deletions(-)
rewrite src/md5.c (93%)
rewrite src/md5.h (98%)
diff --git a/src/dvd_reader.c b/src/dvd_reader.c
index 3fd7363..3dff649 100644
--- a/src/dvd_reader.c
+++ b/src/dvd_reader.c
@@ -1361,7 +1361,7 @@ ssize_t DVDFileSize( dvd_file_t *dvd_file )
int DVDDiscID( dvd_reader_t *dvd, unsigned char *discid )
{
- struct md5_ctx ctx;
+ struct md5_s ctx;
int title;
int title_sets;
int nr_of_files = 0;
@@ -1386,7 +1386,7 @@ int DVDDiscID( dvd_reader_t *dvd, unsigned char *discid )
/* Go through the first IFO:s, in order, up until the tenth,
* and md5sum them, i.e VIDEO_TS.IFO and VTS_0?_0.IFO */
- md5_init_ctx( &ctx );
+ InitMD5( &ctx );
for( title = 0; title < title_sets; title++ ) {
dvd_file_t *dvd_file = DVDOpenFile( dvd, title, DVD_READ_INFO_FILE );
if( dvd_file != NULL ) {
@@ -1411,14 +1411,15 @@ int DVDDiscID( dvd_reader_t *dvd, unsigned char *discid )
return -1;
}
- md5_process_bytes( buffer, file_size, &ctx );
+ AddMD5( &ctx, buffer, file_size );
DVDCloseFile( dvd_file );
free( buffer_base );
nr_of_files++;
}
}
- md5_finish_ctx( &ctx, discid );
+ EndMD5( &ctx );
+ memcpy( discid, ctx.buf, 16 );
if(!nr_of_files)
return -1;
diff --git a/src/md5.c b/src/md5.c
dissimilarity index 93%
index 9c5f50d..54f4ed0 100644
--- a/src/md5.c
+++ b/src/md5.c
@@ -1,402 +1,346 @@
-/* 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, 2001 Free Software Foundation, Inc.
- NOTE: The canonical source of this file is maintained with the GNU C
- Library. Bugs can be reported to bug-glibc at prep.ai.mit.edu.
-
- 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.
-
- This program 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.
-
- 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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. */
-
-/* Written by Ulrich Drepper <drepper at gnu.ai.mit.edu>, 1995. */
-
-#include "config.h"
-#include <sys/types.h>
-
-#include <stdlib.h>
-#include <string.h>
-
-#include "md5.h"
-/* #include "unlocked-io.h" */
-
-
-#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;
-{
- /* 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;
-
- memcpy (&ctx->buffer[left_over], buffer, add);
- ctx->buflen += add;
-
- 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;
- }
-}
-
-
-/* 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; \
- a = rol (a, s); \
- a += b; \
- } \
- while (0)
-
- /* 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, or
- perl -e 'foreach(1..64){printf "0x%08x\n", int (4294967296 * abs (sin $_))}'
- */
-
- /* 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; \
- a = rol (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;
-}
+/*****************************************************************************
+ * md5.c: not so strong MD5 hashing
+ *****************************************************************************
+ * Copyright (C) 1995,1996,1998,1999,2001,2002,
+ * 2003 Free Software Foundation, Inc.
+ *
+ * This program 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 program 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 program; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
+ *****************************************************************************/
+
+/* md5.c - MD5 Message-Digest Algorithm
+ *
+ * According to the definition of MD5 in RFC 1321 from April 1992.
+ * NOTE: This is *not* the same file as the one from glibc.
+ * Written by Ulrich Drepper <drepper at gnu.ai.mit.edu>, 1995.
+ * heavily modified for GnuPG by Werner Koch <wk at gnupg.org>
+ */
+
+/* Test values:
+ * "" D4 1D 8C D9 8F 00 B2 04 E9 80 09 98 EC F8 42 7E
+ * "a" 0C C1 75 B9 C0 F1 B6 A8 31 C3 99 E2 69 77 26 61
+ * "abc 90 01 50 98 3C D2 4F B0 D6 96 3F 7D 28 E1 7F 72
+ * "message digest" F9 6B 69 7D 7C B7 93 8D 52 5A 2F 31 AA F1 61 D0
+ */
+
+#include "config.h"
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "md5.h"
+
+typedef uint32_t u32;
+typedef uint8_t byte;
+#define rol(x,n) ( ((x) << (n)) | ((x) >> (32-(n))) )
+
+typedef struct md5_s MD5_CONTEXT;
+
+
+static void
+md5_init( void *context )
+{
+ MD5_CONTEXT *ctx = context;
+
+ ctx->A = 0x67452301;
+ ctx->B = 0xefcdab89;
+ ctx->C = 0x98badcfe;
+ ctx->D = 0x10325476;
+
+ ctx->nblocks = 0;
+ ctx->count = 0;
+}
+
+
+/* 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))
+
+
+/****************
+ * transform n*64 bytes
+ */
+static void
+transform ( MD5_CONTEXT *ctx, const unsigned char *data )
+{
+ u32 correct_words[16];
+ register u32 A = ctx->A;
+ register u32 B = ctx->B;
+ register u32 C = ctx->C;
+ register u32 D = ctx->D;
+ u32 *cwp = correct_words;
+
+#ifdef WORDS_BIGENDIAN
+ {
+ int i;
+ byte *p2, *p1;
+ for(i=0, p1=data, p2=(byte*)correct_words; i < 16; i++, p2 += 4 )
+ {
+ p2[3] = *p1++;
+ p2[2] = *p1++;
+ p2[1] = *p1++;
+ p2[0] = *p1++;
+ }
+ }
+#else
+ memcpy( correct_words, data, 64 );
+#endif
+
+
+#define OP(a, b, c, d, s, T) \
+ do \
+ { \
+ a += FF (b, c, d) + (*cwp++) + T; \
+ a = rol(a, s); \
+ a += b; \
+ } \
+ while (0)
+
+ /* Before we start, one word about 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);
+
+#undef OP
+#define OP(f, a, b, c, d, k, s, T) \
+ do \
+ { \
+ a += f (b, c, d) + correct_words[k] + T; \
+ a = rol(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);
+
+ /* Put checksum in context given as argument. */
+ ctx->A += A;
+ ctx->B += B;
+ ctx->C += C;
+ ctx->D += D;
+}
+
+
+
+/* The routine updates the message-digest context to
+ * account for the presence of each of the characters inBuf[0..inLen-1]
+ * in the message whose digest is being computed.
+ */
+static void
+md5_write( void *context, const void *inbuf_arg , size_t inlen)
+{
+ const unsigned char *inbuf = inbuf_arg;
+ MD5_CONTEXT *hd = context;
+
+ if( hd->count == 64 ) /* flush the buffer */
+ {
+ transform( hd, hd->buf );
+ hd->count = 0;
+ hd->nblocks++;
+ }
+ if( !inbuf )
+ return;
+
+ if( hd->count )
+ {
+ for( ; inlen && hd->count < 64; inlen-- )
+ hd->buf[hd->count++] = *inbuf++;
+ md5_write( hd, NULL, 0 );
+ if( !inlen )
+ return;
+ }
+
+ while( inlen >= 64 )
+ {
+ transform( hd, inbuf );
+ hd->count = 0;
+ hd->nblocks++;
+ inlen -= 64;
+ inbuf += 64;
+ }
+ for( ; inlen && hd->count < 64; inlen-- )
+ hd->buf[hd->count++] = *inbuf++;
+
+}
+
+
+
+/* The routine final terminates the message-digest computation and
+ * ends with the desired message digest in mdContext->digest[0...15].
+ * The handle is prepared for a new MD5 cycle.
+ * Returns 16 bytes representing the digest.
+ */
+
+static void
+md5_final( void *context)
+{
+ MD5_CONTEXT *hd = context;
+ u32 t, msb, lsb;
+ byte *p;
+
+ md5_write(hd, NULL, 0); /* flush */;
+
+ t = hd->nblocks;
+ /* multiply by 64 to make a byte count */
+ lsb = t << 6;
+ msb = t >> 26;
+ /* add the count */
+ t = lsb;
+ if( (lsb += hd->count) < t )
+ msb++;
+ /* multiply by 8 to make a bit count */
+ t = lsb;
+ lsb <<= 3;
+ msb <<= 3;
+ msb |= t >> 29;
+
+ if( hd->count < 56 ) /* enough room */
+ {
+ hd->buf[hd->count++] = 0x80; /* pad */
+ while( hd->count < 56 )
+ hd->buf[hd->count++] = 0; /* pad */
+ }
+ else /* need one extra block */
+ {
+ hd->buf[hd->count++] = 0x80; /* pad character */
+ while( hd->count < 64 )
+ hd->buf[hd->count++] = 0;
+ md5_write(hd, NULL, 0); /* flush */;
+ memset(hd->buf, 0, 56 ); /* fill next block with zeroes */
+ }
+ /* append the 64 bit count */
+ hd->buf[56] = lsb ;
+ hd->buf[57] = lsb >> 8;
+ hd->buf[58] = lsb >> 16;
+ hd->buf[59] = lsb >> 24;
+ hd->buf[60] = msb ;
+ hd->buf[61] = msb >> 8;
+ hd->buf[62] = msb >> 16;
+ hd->buf[63] = msb >> 24;
+ transform( hd, hd->buf );
+
+ p = hd->buf;
+#ifdef WORDS_BIGENDIAN
+#define X(a) do { *p++ = hd->a ; *p++ = hd->a >> 8; \
+ *p++ = hd->a >> 16; *p++ = hd->a >> 24; } while(0)
+#else /* little endian */
+#define X(a) do { *(u32*)p = (*hd).a ; p += 4; } while(0)
+#endif
+ X(A);
+ X(B);
+ X(C);
+ X(D);
+#undef X
+
+}
+
+#if 0
+static byte *
+md5_read( void *context )
+{
+ MD5_CONTEXT *hd = (MD5_CONTEXT *) context;
+ return hd->buf;
+}
+#endif
+
+void InitMD5( struct md5_s *h )
+{
+ md5_init( h );
+}
+
+void AddMD5( struct md5_s *h, const void *data, size_t len )
+{
+ md5_write( h, data, len );
+}
+
+void EndMD5( struct md5_s *h )
+{
+ md5_final( h );
+}
diff --git a/src/md5.h b/src/md5.h
dissimilarity index 98%
index 3daaf1a..50ce88c 100644
--- a/src/md5.h
+++ b/src/md5.h
@@ -1,161 +1,46 @@
-/* md5.h - Declaration of functions and data types used for MD5 sum
- computing library functions.
- Copyright (C) 1995, 1996, 1999 Free Software Foundation, Inc.
- NOTE: The canonical source of this file is maintained with the GNU C
- Library. Bugs can be reported to bug-glibc at prep.ai.mit.edu.
-
- 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.
-
- This program 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.
-
- 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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. */
-
-#ifndef LIBDVDREAD_MD5_H
-#define LIBDVDREAD_MD5_H
-
-#include <stdio.h>
-
-#if defined HAVE_LIMITS_H || defined _LIBC
-# include <limits.h>
-#endif
-
-/* The following contortions are an attempt to use the C preprocessor
- to determine an unsigned integral type that is 32 bits wide. An
- alternative approach is to use autoconf's AC_CHECK_SIZEOF macro, but
- doing that would require that the configure script compile and *run*
- the resulting executable. Locally running cross-compiled executables
- is usually not possible. */
-
-#ifdef _LIBC
-# include <sys/types.h>
-typedef u_int32_t md5_uint32;
-#else
-# if defined __STDC__ && __STDC__
-# define UINT_MAX_32_BITS 4294967295U
-# else
-# define UINT_MAX_32_BITS 0xFFFFFFFF
-# endif
-
-/* If UINT_MAX isn't defined, assume it's a 32-bit type.
- This should be valid for all systems GNU cares about because
- that doesn't include 16-bit systems, and only modern systems
- (that certainly have <limits.h>) have 64+-bit integral types. */
-
-# ifndef UINT_MAX
-# define UINT_MAX UINT_MAX_32_BITS
-# endif
-
-# if UINT_MAX == UINT_MAX_32_BITS
-typedef unsigned int md5_uint32;
-# else
-# if USHRT_MAX == UINT_MAX_32_BITS
-typedef unsigned short md5_uint32;
-# else
-# if ULONG_MAX == UINT_MAX_32_BITS
-typedef unsigned long md5_uint32;
-# else
-/* The following line is intended to evoke an error.
- Using #error is not portable enough. */
-"Cannot determine unsigned 32-bit data type."
-# endif
-# endif
-# endif
-#endif
-
-#undef __P
-#if defined (__STDC__) && __STDC__
-#define __P(x) x
-#else
-#define __P(x) ()
-#endif
-
-/* Structure to save state of computation between the single steps. */
-struct md5_ctx
-{
- md5_uint32 A;
- md5_uint32 B;
- md5_uint32 C;
- md5_uint32 D;
-
- md5_uint32 total[2];
- md5_uint32 buflen;
- char buffer[128];
-};
-
-/*
- * The following three functions are build up the low level used in
- * the functions `md5_stream' and `md5_buffer'.
- */
-
-/* Initialize structure containing state of computation.
- (RFC 1321, 3.3: Step 3) */
-extern void md5_init_ctx __P ((struct md5_ctx *ctx));
-
-/* Starting with the result of former calls of this function (or the
- initialization function update the context for the next LEN bytes
- starting at BUFFER.
- It is necessary that LEN is a multiple of 64!!! */
-extern void md5_process_block __P ((const void *buffer, size_t len,
- struct md5_ctx *ctx));
-
-/* Starting with the result of former calls of this function (or the
- initialization function update the context for the next LEN bytes
- starting at BUFFER.
- It is NOT required that LEN is a multiple of 64. */
-extern void md5_process_bytes __P ((const void *buffer, size_t len,
- struct md5_ctx *ctx));
-
-/* Process the remaining bytes in the buffer and put result from CTX
- in first 16 bytes following RESBUF. 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.
-
- IMPORTANT: On some systems it is required that RESBUF be correctly
- aligned for a 32 bits value. */
-extern void *md5_finish_ctx __P ((struct md5_ctx *ctx, void *resbuf));
-
-
-/* Put result from CTX in first 16 bytes following RESBUF. 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.
-
- IMPORTANT: On some systems it is required that RESBUF is correctly
- aligned for a 32 bits value. */
-extern void *md5_read_ctx __P ((const struct md5_ctx *ctx, void *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. */
-extern int md5_stream __P ((FILE *stream, void *resblock));
-
-/* 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. */
-extern void *md5_buffer __P ((const char *buffer, size_t len, void *resblock));
-
-/* The following is from gnupg-1.0.2's cipher/bithelp.h. */
-/* Rotate a 32 bit integer by n bytes */
-#if defined __GNUC__ && defined __i386__
-static inline md5_uint32
-rol(md5_uint32 x, int n)
-{
- __asm__("roll %%cl,%0"
- :"=r" (x)
- :"0" (x),"c" (n));
- return x;
-}
-#else
-# define rol(x,n) ( ((x) << (n)) | ((x) >> (32-(n))) )
-#endif
-
-#endif /* LIBDVDREAD_MD5_H */
+/*****************************************************************************
+ * md5.h: MD5 hash
+ *****************************************************************************
+ * Copyright © 2004-2011 VLC authors and VideoLAN
+ *
+ * Authors: Rémi Denis-Courmont
+ * Rafaël Carré
+ *
+ * This program 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 program 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 program; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
+ *****************************************************************************/
+
+#ifndef LIBDVDREAD_MD5_H
+#define LIBDVDREAD_MD5_H
+
+#include <stdint.h>
+
+/**
+ * \file
+ * This file defines functions and structures to compute MD5 digests
+ */
+
+struct md5_s
+{
+ uint32_t A, B, C, D; /* chaining variables */
+ uint32_t nblocks;
+ uint8_t buf[64];
+ int count;
+};
+
+void InitMD5( struct md5_s * );
+void AddMD5( struct md5_s *, const void *, size_t );
+void EndMD5( struct md5_s * );
+
+#endif
--
1.9.3
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