From 1f47f54b74c6838a93b43b485a290c7463f2531b Mon Sep 17 00:00:00 2001
From: Christian Heimes <christian@python.org>
Date: Wed, 7 Sep 2016 11:58:24 +0200
Subject: Issue #16113: Add SHA-3 and SHAKE support to hashlib module.

---
 Modules/_sha3/kcp/KeccakHash.c | 82 ++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 82 insertions(+)
 create mode 100644 Modules/_sha3/kcp/KeccakHash.c

(limited to 'Modules/_sha3/kcp/KeccakHash.c')

diff --git a/Modules/_sha3/kcp/KeccakHash.c b/Modules/_sha3/kcp/KeccakHash.c
new file mode 100644
index 0000000000..e09fb43cac
--- /dev/null
+++ b/Modules/_sha3/kcp/KeccakHash.c
@@ -0,0 +1,82 @@
+/*
+Implementation by the Keccak, Keyak and Ketje Teams, namely, Guido Bertoni,
+Joan Daemen, Michaël Peeters, Gilles Van Assche and Ronny Van Keer, hereby
+denoted as "the implementer".
+
+For more information, feedback or questions, please refer to our websites:
+http://keccak.noekeon.org/
+http://keyak.noekeon.org/
+http://ketje.noekeon.org/
+
+To the extent possible under law, the implementer has waived all copyright
+and related or neighboring rights to the source code in this file.
+http://creativecommons.org/publicdomain/zero/1.0/
+*/
+
+#include <string.h>
+#include "KeccakHash.h"
+
+/* ---------------------------------------------------------------- */
+
+HashReturn Keccak_HashInitialize(Keccak_HashInstance *instance, unsigned int rate, unsigned int capacity, unsigned int hashbitlen, unsigned char delimitedSuffix)
+{
+    HashReturn result;
+
+    if (delimitedSuffix == 0)
+        return FAIL;
+    result = (HashReturn)KeccakWidth1600_SpongeInitialize(&instance->sponge, rate, capacity);
+    if (result != SUCCESS)
+        return result;
+    instance->fixedOutputLength = hashbitlen;
+    instance->delimitedSuffix = delimitedSuffix;
+    return SUCCESS;
+}
+
+/* ---------------------------------------------------------------- */
+
+HashReturn Keccak_HashUpdate(Keccak_HashInstance *instance, const BitSequence *data, DataLength databitlen)
+{
+    if ((databitlen % 8) == 0)
+        return (HashReturn)KeccakWidth1600_SpongeAbsorb(&instance->sponge, data, databitlen/8);
+    else {
+        HashReturn ret = (HashReturn)KeccakWidth1600_SpongeAbsorb(&instance->sponge, data, databitlen/8);
+        if (ret == SUCCESS) {
+            /* The last partial byte is assumed to be aligned on the least significant bits */
+
+            unsigned char lastByte = data[databitlen/8];
+            /* Concatenate the last few bits provided here with those of the suffix */
+
+            unsigned short delimitedLastBytes = (unsigned short)((unsigned short)lastByte | ((unsigned short)instance->delimitedSuffix << (databitlen % 8)));
+            if ((delimitedLastBytes & 0xFF00) == 0x0000) {
+                instance->delimitedSuffix = delimitedLastBytes & 0xFF;
+            }
+            else {
+                unsigned char oneByte[1];
+                oneByte[0] = delimitedLastBytes & 0xFF;
+                ret = (HashReturn)KeccakWidth1600_SpongeAbsorb(&instance->sponge, oneByte, 1);
+                instance->delimitedSuffix = (delimitedLastBytes >> 8) & 0xFF;
+            }
+        }
+        return ret;
+    }
+}
+
+/* ---------------------------------------------------------------- */
+
+HashReturn Keccak_HashFinal(Keccak_HashInstance *instance, BitSequence *hashval)
+{
+    HashReturn ret = (HashReturn)KeccakWidth1600_SpongeAbsorbLastFewBits(&instance->sponge, instance->delimitedSuffix);
+    if (ret == SUCCESS)
+        return (HashReturn)KeccakWidth1600_SpongeSqueeze(&instance->sponge, hashval, instance->fixedOutputLength/8);
+    else
+        return ret;
+}
+
+/* ---------------------------------------------------------------- */
+
+HashReturn Keccak_HashSqueeze(Keccak_HashInstance *instance, BitSequence *data, DataLength databitlen)
+{
+    if ((databitlen % 8) != 0)
+        return FAIL;
+    return (HashReturn)KeccakWidth1600_SpongeSqueeze(&instance->sponge, data, databitlen/8);
+}
-- 
cgit v1.2.1