- for protocol version >= 27, mdfour_tail() is called when the block size

[rsync/rsync.git] / lib / mdfour.c

diff --git a/lib/mdfour.c b/lib/mdfour.c
index c7bc7ab..d8e8632 100644 (file)
--- a/lib/mdfour.c
+++ b/lib/mdfour.c
@@ -109,29 +109,53 @@ void mdfour_begin(struct mdfour *md)
        md->C = 0x98badcfe;
        md->D = 0x10325476;
        md->totalN = 0;
+       md->totalN2 = 0;
 }
 
 
-static void mdfour_tail(unsigned char *in, int n)
+static void mdfour_tail(unsigned char *in, uint32 n)
 {
        unsigned char buf[128];
        uint32 M[16];
-       uint32 b;
-
-       m->totalN += n;
-
-       b = m->totalN * 8;
+       extern int remote_version;
+
+       /*
+        * Count total number of bits, modulo 2^64
+        */
+       m->totalN += n << 3;
+       if (m->totalN < (n << 3)) {
+               m->totalN2++;
+       }
+       m->totalN2 += n >> 29;
 
        memset(buf, 0, 128);
        if (n) memcpy(buf, in, n);
        buf[n] = 0x80;
 
        if (n <= 55) {
-               copy4(buf+56, b);
+               copy4(buf+56, m->totalN);
+               /*
+                * Prior to protocol version 27 only the number of bits
+                * modulo 2^32 was included.  MD4 requires the number
+                * of bits modulo 2^64, which was fixed starting with
+                * protocol version 27.
+                */
+               if (remote_version >= 27) {
+                       copy4(buf+60, m->totalN2);
+               }
                copy64(M, buf);
                mdfour64(M);
        } else {
-               copy4(buf+120, b); 
+               copy4(buf+120, m->totalN); 
+               /*
+                * Prior to protocol version 27 only the number of bits
+                * modulo 2^32 was included.  MD4 requires the number
+                * of bits modulo 2^64, which was fixed starting with
+                * protocol version 27.
+                */
+               if (remote_version >= 27) {
+                       copy4(buf+124, m->totalN2); 
+               }
                copy64(M, buf);
                mdfour64(M);
                copy64(M, buf+64);
@@ -139,20 +163,23 @@ static void mdfour_tail(unsigned char *in, int n)
        }
 }
 
-void mdfour_update(struct mdfour *md, unsigned char *in, int n)
+void mdfour_update(struct mdfour *md, unsigned char *in, uint32 n)
 {
        uint32 M[16];
 
-       if (n == 0) mdfour_tail(in, n);
-
        m = md;
 
+       if (n == 0) mdfour_tail(in, n);
+
        while (n >= 64) {
                copy64(M, in);
                mdfour64(M);
                in += 64;
                n -= 64;
-               m->totalN += 64;
+               m->totalN += 64 << 3;
+               if (m->totalN < 64 << 3) {
+                       m->totalN2++;
+               }
        }
 
        if (n) mdfour_tail(in, n);