fix for issue 1118: check if iv is zero in gcm.
1) found by roberto in mbedtls forum
2) if iv_len is zero, return an error
3) add tests for invalid parameters
diff --git a/ChangeLog b/ChangeLog
index 741d1f4..4f7a005 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,6 +1,10 @@
mbed TLS ChangeLog (Sorted per branch, date)
-= mbed TLS 2.x.x released xxxx-xx-xx
+= mbed TLS x.x.x branch released xxxx-xx-xx
+
+Bugfix
+ * Add a check if iv_len is zero, and return an error if it is zero. reported
+ by roberto. #716
Features
* Add the functions mbedtls_platform_setup() and mbedtls_platform_teardown()