diff --git a/ChangeLog b/ChangeLog
index fd005c765090f5b60f6cb95b6b107d111e96e57e..3fe0600b2f2fb4f237c25da8c18023574ce91cb5 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,14 @@
+2015-08-24  Niels Möller  <nisse@lysator.liu.se>
+
+	* testsuite/sha3.awk: Document origin of test vectors.
+
+	From Nikos Mavrogiannopoulos.
+	* sha3.c (_sha3_pad): Update for NIST version.
+	* testsuite/sha3-224-test.c: Updated test vectors.
+	* testsuite/sha3-256-test.c: Likewise.
+	* testsuite/sha3-384-test.c: Likewise.
+	* testsuite/sha3-512-test.c: Likewise.
+
 2015-06-03  Niels Möller  <nisse@lysator.liu.se>
 
 	* arm/neon/chacha-core-internal.asm: New file. 55% speedup over C
diff --git a/testsuite/sha3.awk b/testsuite/sha3.awk
index f7efa609a3c23ec3130085594b7e49d26f8fc9fd..9031c59dbdeb390c235ff7f81af7f5872d723d5a 100755
--- a/testsuite/sha3.awk
+++ b/testsuite/sha3.awk
@@ -1,5 +1,10 @@
 #! /usr/bin/awk -f
 
+# This script is used to process the Keccak testvectors, originally
+# we used http://keccak.noekeon.org/KeccakKAT-3.zip.
+# For the updated NIST version, test vectors can be found at
+# https://github.com/gvanas/KeccakCodePackage/tree/master/TestVectors
+
 /^Len/ { len = $3 }
 /^Msg/ { msg = $3 }
 /^MD/ { md = $3;