* libmisc/obscure.c, libmisc/salt.c, src/passwd.c: Match DES, MD5,

SHA256, and SHA512 exactly (not only the first 3/6 chars).
* libmisc/salt.c (SHA_salt_rounds): Set rounds to the specified
  prefered_rounds value, if specified.
* src/gpasswd.c, libmisc/salt.c: Fix compilation warnings (use
  size_t for lengths).
* src/chpasswd.c, src/chgpasswd.c: Add missing parenthesis.

libmisc/obscure.c

@@ -245,9 +245,9 @@ static const char *password_check (const char *old, const char *new,
 #ifdef ENCRYPTMETHOD_SELECT
 	} else {
 
-		if (!strncmp (result, "MD5"   , 3) ||
-		    !strncmp (result, "SHA256", 6) ||
-		    !strncmp (result, "SHA512", 6))
+		if (!strcmp (result, "MD5") ||
+		    !strcmp (result, "SHA256") ||
+		    !strcmp (result, "SHA512"))
 			return NULL;
 
 	}