1 file changed, 4 insertions, 1 deletion
diff --git a/tests/extensions/harness.lua b/tests/extensions/harness.lua
index 1a669ff..ead3c97 100644
--- a/tests/extensions/harness.lua
+++ b/tests/extensions/harness.lua
@@ -311,11 +311,14 @@ function harness.stub_auth_modules()
 			return table.concat(out)
 		end,
 	})
+	-- An HMAC-SHA256 is 32 bytes, twice what one fake digest gives, so two
+	-- of different input are joined to make signatures the real length.
 	preload("openssl.hmac", {
 		new = function(key, algorithm)
 			return {
 				final = function(self, payload)
-					return fake_digest_bytes(key .. "\1" .. algorithm .. "\1" .. payload)
+					local text = key .. "\1" .. algorithm .. "\1" .. payload
+					return fake_digest_bytes(text) .. fake_digest_bytes("\2" .. text)
 				end,
 			}
 		end,