Add len constants to certs.c
diff --git a/ChangeLog b/ChangeLog
index 82c9a88..b0354d5 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -6,6 +6,8 @@
   * Support for DTLS 1.0 and 1.2 (RFC 6347).
 
 API Changes
+   * Test certificates in cert.s are no longer guaranteed to be nul-terminated
+     strings; use the new *_len variables instead of strlen().
    * md_init_ctx() is deprecated in favour of md_setup(), that adds a third
      argument (allowing memory savings if HMAC is not used)
    * Removed individual mdX_hmac and shaX_hmac functions (use generic