[or-cvs] bugfix: our integrity-checking digest was checking only the...

[Roger Dingledine]

Update of /home/or/cvsroot/src/common
In directory moria.mit.edu:/home2/arma/work/onion/cvs/src/common

Modified Files:
	crypto.c 
Log Message:
bugfix: our integrity-checking digest was checking only the most
recent cell, not the previous cells like we'd thought.

this change is backward incompatible.


Index: crypto.c
===================================================================
RCS file: /home/or/cvsroot/src/common/crypto.c,v
retrieving revision 1.92
retrieving revision 1.93
diff -u -d -r1.92 -r1.93
--- crypto.c	12 May 2004 19:30:28 -0000	1.92
+++ crypto.c	15 May 2004 23:49:41 -0000	1.93
@@ -1029,9 +1029,12 @@
                               char *out, size_t out_len)
 {
   static char r[DIGEST_LEN];
+  SHA_CTX tmpctx;
   tor_assert(digest && out);
   tor_assert(out_len <= DIGEST_LEN);
-  SHA1_Final(r, &digest->d);
+  /* memcpy into a temporary ctx, since SHA1_Final clears the context */
+  memcpy(&tmpctx, &digest->d, sizeof(SHA_CTX));
+  SHA1_Final(r, &tmpctx);
   memcpy(out, r, out_len);
 }