[or-cvs] Fix a bug in parsing HashedControlPassword.

[Nick Mathewson]

Update of /home/or/cvsroot/tor/src/or
In directory moria.mit.edu:/tmp/cvs-serv26623/src/or

Modified Files:
	config.c control.c or.h 
Log Message:
Fix a bug in parsing HashedControlPassword.

Index: config.c
===================================================================
RCS file: /home/or/cvsroot/tor/src/or/config.c,v
retrieving revision 1.284
retrieving revision 1.285
diff -u -d -r1.284 -r1.285
--- config.c	8 Dec 2004 00:40:32 -0000	1.284
+++ config.c	13 Dec 2004 18:32:29 -0000	1.285
@@ -1402,9 +1402,7 @@
   }
 
   if (options->HashedControlPassword) {
-    char buf[S2K_SPECIFIER_LEN+DIGEST_LEN];
-    if (base64_decode(buf,sizeof(buf),options->HashedControlPassword,
-                      strlen(options->HashedControlPassword)!=sizeof(buf))) {
+    if (decode_hashed_password(NULL, options->HashedControlPassword)<0) {
       log_fn(LOG_WARN,"Bad HashedControlPassword: wrong length or bad base64");
       result = -1;
     }

Index: control.c
===================================================================
RCS file: /home/or/cvsroot/tor/src/or/control.c,v
retrieving revision 1.35
retrieving revision 1.36
diff -u -d -r1.35 -r1.36
--- control.c	13 Dec 2004 00:44:38 -0000	1.35
+++ control.c	13 Dec 2004 18:32:29 -0000	1.36
@@ -324,6 +324,31 @@
   return 0;
 }
 
+/** Decode the hashed, base64'd password stored in <b>hashed</b>.  If
+ * <b>buf</b> is provided, store the hashed password in the first
+ * S2K_SPECIFIER_LEN+DIGEST_LEN bytes of <b>buf</b>.  Return 0 on
+ * success, -1 on failure.
+ */
+int
+decode_hashed_password(char *buf, const char *hashed)
+{
+  size_t len = strlen(hashed)+2;
+  char *base64 = tor_malloc(len);
+  char decoded[64];
+  int r;
+  if (tor_snprintf(base64, len, "%s\n", hashed)<0)
+    return -1;
+  if ((r =  base64_decode(decoded, sizeof(decoded),
+                          base64, strlen(base64))) !=
+      S2K_SPECIFIER_LEN+DIGEST_LEN) {
+    printf("BB %d\n",r);
+    return -1;
+  }
+  if (buf)
+    memcpy(buf, decoded, sizeof(decoded));
+  return 0;
+}
+
 /** Called when we get an AUTHENTICATE message.  Check whether the
  * authentication is valid, and if so, update the connection's state to
  * OPEN.  Reply with DONE or ERROR.
@@ -340,9 +365,7 @@
   } else if (options->HashedControlPassword) {
     char expected[S2K_SPECIFIER_LEN+DIGEST_LEN];
     char received[DIGEST_LEN];
-    if (base64_decode(expected,sizeof(expected),
-                      options->HashedControlPassword,
-                      strlen(options->HashedControlPassword))<0) {
+    if (decode_hashed_password(expected, options->HashedControlPassword)<0) {
       log_fn(LOG_WARN,"Couldn't decode HashedControlPassword: invalid base64");
       goto err;
     }

Index: or.h
===================================================================
RCS file: /home/or/cvsroot/tor/src/or/or.h,v
retrieving revision 1.507
retrieving revision 1.508
diff -u -d -r1.507 -r1.508
--- or.h	7 Dec 2004 15:29:54 -0000	1.507
+++ or.h	13 Dec 2004 18:32:29 -0000	1.508
@@ -1294,6 +1294,7 @@
 void control_event_logmsg(int severity, const char *msg);
 
 int init_cookie_authentication(int enabled);
+int decode_hashed_password(char *buf, const char *hashed);
 
 /********************************* cpuworker.c *****************************/