X-Git-Url: https://mattmccutchen.net/rsync/rsync.git/blobdiff_plain/f855a7d01ab8401a307bb02cdcdee546df3e2423..afd8bdb9073aaf28180eacb90fe14a473a76d132:/checksum.c

diff --git a/checksum.c b/checksum.c
index 194d899a..ff9b1faa 100644
--- a/checksum.c
+++ b/checksum.c
@@ -23,8 +23,8 @@ int csum_length=2; /* initial value */
 
 #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
@@ -58,7 +58,7 @@ void get_checksum2(char *buf,int len,char *sum)
 
 	if (len > len1) {
 		if (buf1) free(buf1);
-		buf1 = (char *)malloc(len+4);
+		buf1 = new_array(char, len+4);
 		len1 = len;
 		if (!buf1) out_of_memory("get_checksum2");
 	}
@@ -74,7 +74,13 @@ void get_checksum2(char *buf,int len,char *sum)
 	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));
 	}
 	
@@ -88,12 +94,11 @@ void file_checksum(char *fname,char *sum,OFF_T size)
 	struct map_struct *buf;
 	int fd;
 	OFF_T len = size;
-	char tmpchunk[CSUM_CHUNK];
 	struct mdfour m;
 	
 	memset(sum,0,MD4_SUM_LENGTH);
 	
-	fd = open(fname,O_RDONLY);
+	fd = do_open(fname, O_RDONLY, 0);
 	if (fd == -1) return;
 	
 	buf = map_file(fd,size);
@@ -101,14 +106,16 @@ void file_checksum(char *fname,char *sum,OFF_T size)
 	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);
 
@@ -117,30 +124,28 @@ void file_checksum(char *fname,char *sum,OFF_T size)
 }
 
 
-void checksum_init(void)
-{
-  if (remote_version >= 14)
-    csum_length = 2; /* adaptive */
-  else
-    csum_length = SUM_LENGTH;
-}
-
-
-
 static int 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, int len)
 {
 	int i;
 	if (len + sumresidue < CSUM_CHUNK) {
@@ -172,7 +177,7 @@ void sum_update(char *p,int len)
 
 void sum_end(char *sum)
 {
-	if (sumresidue) {
+	if (sumresidue || protocol_version >= 27) {
 		mdfour_update(&md, (uchar *)sumrbuf, sumresidue);
 	}