Begin implementing HKDF

Implement the `extract` phase of HKDF.

1 files changed, 45 insertions, 0 deletions

diff --git a/src/Internal/HKDF.chs b/src/Internal/HKDF.chs
new file mode 100644
index 0000000..a3a48ed
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+++ b/src/Internal/HKDF.chs
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+-- Copyright 2018 Google LLC
+--
+-- Licensed under the Apache License, Version 2.0 (the "License"); you may not
+-- use this file except in compliance with the License. You may obtain a copy of
+-- the License at
+--
+--     https://www.apache.org/licenses/LICENSE-2.0
+--
+-- Unless required by applicable law or agreed to in writing, software
+-- distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+-- WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+-- License for the specific language governing permissions and limitations under
+-- the License.
+
+module Internal.HKDF
+  ( hkdfExtract, hkdfExpand
+  ) where
+
+import Foreign (Ptr)
+import Foreign.C.Types
+
+{#import Internal.Base#}
+import Result
+
+#include <openssl/hkdf.h>
+
+hkdfExtract ::
+  Ptr CUChar -> Ptr CULong
+  -> Ptr EVPMD
+  -> Ptr CUChar -> CULong
+  -> Ptr CUChar -> CULong
+  -> IO ()
+hkdfExtract outKey outLen digest secret secretLen salt saltLen =
+  requireSuccess $
+    {#call HKDF_extract as ^#} outKey outLen digest secret secretLen salt saltLen
+
+hkdfExpand ::
+  Ptr CUChar -> CULong
+  -> Ptr EVPMD
+  -> Ptr CUChar -> CULong
+  -> Ptr CUChar -> CULong
+  -> IO ()
+hkdfExpand outKey outLen digest prk prkLen info infoLen =
+  requireSuccess $
+    {#call HKDF_expand as ^#} outKey outLen digest prk prkLen info infoLen