-/*
- Copyright (C) Andrew Tridgell 1996
- Copyright (C) Paul Mackerras 1996
-
- 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 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 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.
-*/
+/*
+ * Routines to support checksumming of bytes.
+ *
+ * Copyright (C) 1996 Andrew Tridgell
+ * Copyright (C) 1996 Paul Mackerras
+ * Copyright (C) 2004, 2005 Wayne Davison
+ *
+ * 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 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 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
#include "rsync.h"
#define CSUM_CHUNK 64
-int checksum_seed = 0;
-extern int remote_version;
+extern int checksum_seed;
+extern int protocol_version;
/*
a simple 32 bit checksum that can be upadted from either end
(inspired by Mark Adler's Adler-32 checksum)
*/
-uint32 get_checksum1(char *buf1,int len)
+uint32 get_checksum1(char *buf1, int32 len)
{
- int i;
+ int32 i;
uint32 s1, s2;
schar *buf = (schar *)buf1;
s1 = s2 = 0;
for (i = 0; i < (len-4); i+=4) {
- s2 += 4*(s1 + buf[i]) + 3*buf[i+1] + 2*buf[i+2] + buf[i+3] +
+ s2 += 4*(s1 + buf[i]) + 3*buf[i+1] + 2*buf[i+2] + buf[i+3] +
10*CHAR_OFFSET;
- s1 += (buf[i+0] + buf[i+1] + buf[i+2] + buf[i+3] + 4*CHAR_OFFSET);
+ s1 += (buf[i+0] + buf[i+1] + buf[i+2] + buf[i+3] + 4*CHAR_OFFSET);
}
for (; i < len; i++) {
s1 += (buf[i]+CHAR_OFFSET); s2 += s1;
}
-void get_checksum2(char *buf,int len,char *sum)
+void get_checksum2(char *buf, int32 len, char *sum)
{
- int i;
+ int32 i;
static char *buf1;
- static int len1;
+ static int32 len1;
struct mdfour m;
if (len > len1) {
- if (buf1) free(buf1);
- buf1 = (char *)malloc(len+4);
+ if (buf1)
+ free(buf1);
+ buf1 = new_array(char, len+4);
len1 = len;
- if (!buf1) out_of_memory("get_checksum2");
+ if (!buf1)
+ out_of_memory("get_checksum2");
}
-
+
mdfour_begin(&m);
-
+
memcpy(buf1,buf,len);
if (checksum_seed) {
SIVAL(buf1,len,checksum_seed);
len += 4;
}
-
+
for(i = 0; i + CSUM_CHUNK <= len; i += CSUM_CHUNK) {
mdfour_update(&m, (uchar *)(buf1+i), CSUM_CHUNK);
}
- if (len - i > 0) {
+ /*
+ * Prior to version 27 an incorrect MD4 checksum was computed
+ * by failing to call mdfour_tail() for block sizes that
+ * are multiples of 64. This is fixed by calling mdfour_update()
+ * even when there are no more bytes.
+ */
+ if (len - i > 0 || protocol_version >= 27) {
mdfour_update(&m, (uchar *)(buf1+i), (len-i));
}
-
+
mdfour_result(&m, (uchar *)sum);
}
struct map_struct *buf;
int fd;
OFF_T len = size;
- char tmpchunk[CSUM_CHUNK];
struct mdfour m;
-
+
memset(sum,0,MD4_SUM_LENGTH);
-
+
fd = do_open(fname, O_RDONLY, 0);
- if (fd == -1) return;
-
- buf = map_file(fd,size);
-
+ if (fd == -1)
+ return;
+
+ buf = map_file(fd, size, MAX_MAP_SIZE, CSUM_CHUNK);
+
mdfour_begin(&m);
for(i = 0; i + CSUM_CHUNK <= len; i += CSUM_CHUNK) {
- memcpy(tmpchunk, map_ptr(buf,i,CSUM_CHUNK), CSUM_CHUNK);
- mdfour_update(&m, (uchar *)tmpchunk, CSUM_CHUNK);
+ mdfour_update(&m, (uchar *)map_ptr(buf, i, CSUM_CHUNK),
+ CSUM_CHUNK);
}
- if (len - i > 0) {
- memcpy(tmpchunk, map_ptr(buf,i,len-i), len-i);
- mdfour_update(&m, (uchar *)tmpchunk, (len-i));
- }
+ /* Prior to version 27 an incorrect MD4 checksum was computed
+ * by failing to call mdfour_tail() for block sizes that
+ * are multiples of 64. This is fixed by calling mdfour_update()
+ * even when there are no more bytes. */
+ if (len - i > 0 || protocol_version >= 27)
+ mdfour_update(&m, (uchar *)map_ptr(buf, i, len-i), len-i);
mdfour_result(&m, (uchar *)sum);
}
-void checksum_init(void)
-{
- if (remote_version >= 14)
- csum_length = 2; /* adaptive */
- else
- csum_length = SUM_LENGTH;
-}
-
-
-
-static int sumresidue;
+static int32 sumresidue;
static char sumrbuf[CSUM_CHUNK];
static struct mdfour md;
-void sum_init(void)
+void sum_init(int seed)
{
char s[4];
mdfour_begin(&md);
- sumresidue=0;
- SIVAL(s,0,checksum_seed);
- sum_update(s,4);
+ sumresidue = 0;
+ SIVAL(s, 0, seed);
+ sum_update(s, 4);
}
-void sum_update(char *p,int len)
+/**
+ * Feed data into an MD4 accumulator, md. The results may be
+ * retrieved using sum_end(). md is used for different purposes at
+ * different points during execution.
+ *
+ * @todo Perhaps get rid of md and just pass in the address each time.
+ * Very slightly clearer and slower.
+ **/
+void sum_update(char *p, int32 len)
{
- int i;
if (len + sumresidue < CSUM_CHUNK) {
- memcpy(sumrbuf+sumresidue, p, len);
+ memcpy(sumrbuf + sumresidue, p, len);
sumresidue += len;
return;
}
if (sumresidue) {
- i = MIN(CSUM_CHUNK-sumresidue,len);
- memcpy(sumrbuf+sumresidue,p,i);
- mdfour_update(&md, (uchar *)sumrbuf, (i+sumresidue));
+ int32 i = CSUM_CHUNK - sumresidue;
+ memcpy(sumrbuf + sumresidue, p, i);
+ mdfour_update(&md, (uchar *)sumrbuf, CSUM_CHUNK);
len -= i;
p += i;
}
- for(i = 0; i + CSUM_CHUNK <= len; i += CSUM_CHUNK) {
- memcpy(sumrbuf,p+i,CSUM_CHUNK);
- mdfour_update(&md, (uchar *)sumrbuf, CSUM_CHUNK);
+ while (len >= CSUM_CHUNK) {
+ mdfour_update(&md, (uchar *)p, CSUM_CHUNK);
+ len -= CSUM_CHUNK;
+ p += CSUM_CHUNK;
}
- if (len - i > 0) {
- sumresidue = len-i;
- memcpy(sumrbuf,p+i,sumresidue);
- } else {
- sumresidue = 0;
- }
+ sumresidue = len;
+ if (sumresidue)
+ memcpy(sumrbuf, p, sumresidue);
}
void sum_end(char *sum)
{
- if (sumresidue) {
+ if (sumresidue || protocol_version >= 27)
mdfour_update(&md, (uchar *)sumrbuf, sumresidue);
- }
mdfour_result(&md, (uchar *)sum);
}
Matt McCutchen's Web Site / rsync / rsync.git / blobdiff