Add a simple but functioning implementation of Keccak. Only the

proposed SHA-3 parameter sets are supported.

4 files changed, 239 insertions, 0 deletions

diff --git a/src/engine/core_engine/lookup_hash.cpp b/src/engine/core_engine/lookup_hash.cpp
index e80c1db64..f94a97864 100644
--- a/src/engine/core_engine/lookup_hash.cpp
+++ b/src/engine/core_engine/lookup_hash.cpp
@@ -34,6 +34,10 @@
   #include <botan/has160.h>
 #endif
 
+#if defined(BOTAN_HAS_KECCAK)
+  #include <botan/keccak.h>
+#endif
+
 #if defined(BOTAN_HAS_MD2)
   #include <botan/md2.h>
 #endif
@@ -124,6 +128,11 @@ HashFunction* Core_Engine::find_hash(const SCAN_Name& request,
       return new HAS_160;
 #endif
 
+#if defined(BOTAN_HAS_KECCAK)
+   if(request.algo_name() == "Keccak-1600")
+      return new Keccak_1600(request.arg_as_integer(0, 512));
+#endif
+
 #if defined(BOTAN_HAS_MD2)
    if(request.algo_name() == "MD2")
       return new MD2;
diff --git a/src/hash/keccak/info.txt b/src/hash/keccak/info.txt
new file mode 100644
index 000000000..a2ed48200
--- /dev/null
+++ b/src/hash/keccak/info.txt
@@ -0,0 +1,5 @@
+define KECCAK
+
+<requires>
+alloc
+</requires>
diff --git a/src/hash/keccak/keccak.cpp b/src/hash/keccak/keccak.cpp
new file mode 100644
index 000000000..c1980193e
--- /dev/null
+++ b/src/hash/keccak/keccak.cpp
@@ -0,0 +1,181 @@
+/*
+* Keccak
+* (C) 2010 Jack Lloyd
+*
+* Distributed under the terms of the Botan license
+*/
+
+#include <botan/keccak.h>
+#include <botan/loadstor.h>
+#include <botan/parsing.h>
+#include <botan/exceptn.h>
+#include <botan/rotate.h>
+
+namespace Botan {
+
+namespace {
+
+void keccak_f_1600(u64bit A[25])
+   {
+   static const u64bit RC[24] = {
+      0x0000000000000001, 0x0000000000008082, 0x800000000000808A,
+      0x8000000080008000, 0x000000000000808B, 0x0000000080000001,
+      0x8000000080008081, 0x8000000000008009, 0x000000000000008A,
+      0x0000000000000088, 0x0000000080008009, 0x000000008000000A,
+      0x000000008000808B, 0x800000000000008B, 0x8000000000008089,
+      0x8000000000008003, 0x8000000000008002, 0x8000000000000080,
+      0x000000000000800A, 0x800000008000000A, 0x8000000080008081,
+      0x8000000000008080, 0x0000000080000001, 0x8000000080008008
+   };
+
+   for(size_t i = 0; i != 24; ++i)
+      {
+      const u64bit C0 = A[0] ^ A[5] ^ A[10] ^ A[15] ^ A[20];
+      const u64bit C1 = A[1] ^ A[6] ^ A[11] ^ A[16] ^ A[21];
+      const u64bit C2 = A[2] ^ A[7] ^ A[12] ^ A[17] ^ A[22];
+      const u64bit C3 = A[3] ^ A[8] ^ A[13] ^ A[18] ^ A[23];
+      const u64bit C4 = A[4] ^ A[9] ^ A[14] ^ A[19] ^ A[24];
+
+      const u64bit D0 = rotate_left(C0, 1) ^ C3;
+      const u64bit D1 = rotate_left(C1, 1) ^ C4;
+      const u64bit D2 = rotate_left(C2, 1) ^ C0;
+      const u64bit D3 = rotate_left(C3, 1) ^ C1;
+      const u64bit D4 = rotate_left(C4, 1) ^ C2;
+
+      const u64bit B00 = A[ 0] ^ D1;
+      const u64bit B01 = rotate_left(A[ 6] ^ D2, 44);
+      const u64bit B02 = rotate_left(A[12] ^ D3, 43);
+      const u64bit B03 = rotate_left(A[18] ^ D4, 21);
+      const u64bit B04 = rotate_left(A[24] ^ D0, 14);
+      const u64bit B05 = rotate_left(A[ 3] ^ D4, 28);
+      const u64bit B06 = rotate_left(A[ 9] ^ D0, 20);
+      const u64bit B07 = rotate_left(A[10] ^ D1, 3);
+      const u64bit B08 = rotate_left(A[16] ^ D2, 45);
+      const u64bit B09 = rotate_left(A[22] ^ D3, 61);
+      const u64bit B10 = rotate_left(A[ 1] ^ D2, 1);
+      const u64bit B11 = rotate_left(A[ 7] ^ D3, 6);
+      const u64bit B12 = rotate_left(A[13] ^ D4, 25);
+      const u64bit B13 = rotate_left(A[19] ^ D0, 8);
+      const u64bit B14 = rotate_left(A[20] ^ D1, 18);
+      const u64bit B15 = rotate_left(A[ 4] ^ D0, 27);
+      const u64bit B16 = rotate_left(A[ 5] ^ D1, 36);
+      const u64bit B17 = rotate_left(A[11] ^ D2, 10);
+      const u64bit B18 = rotate_left(A[17] ^ D3, 15);
+      const u64bit B19 = rotate_left(A[23] ^ D4, 56);
+      const u64bit B20 = rotate_left(A[ 2] ^ D3, 62);
+      const u64bit B21 = rotate_left(A[ 8] ^ D4, 55);
+      const u64bit B22 = rotate_left(A[14] ^ D0, 39);
+      const u64bit B23 = rotate_left(A[15] ^ D1, 41);
+      const u64bit B24 = rotate_left(A[21] ^ D2, 2);
+
+      A[ 0] = B00 ^ (~B01 & B02);
+      A[ 1] = B01 ^ (~B02 & B03);
+      A[ 2] = B02 ^ (~B03 & B04);
+      A[ 3] = B03 ^ (~B04 & B00);
+      A[ 4] = B04 ^ (~B00 & B01);
+      A[ 5] = B05 ^ (~B06 & B07);
+      A[ 6] = B06 ^ (~B07 & B08);
+      A[ 7] = B07 ^ (~B08 & B09);
+      A[ 8] = B08 ^ (~B09 & B05);
+      A[ 9] = B09 ^ (~B05 & B06);
+      A[10] = B10 ^ (~B11 & B12);
+      A[11] = B11 ^ (~B12 & B13);
+      A[12] = B12 ^ (~B13 & B14);
+      A[13] = B13 ^ (~B14 & B10);
+      A[14] = B14 ^ (~B10 & B11);
+      A[15] = B15 ^ (~B16 & B17);
+      A[16] = B16 ^ (~B17 & B18);
+      A[17] = B17 ^ (~B18 & B19);
+      A[18] = B18 ^ (~B19 & B15);
+      A[19] = B19 ^ (~B15 & B16);
+      A[20] = B20 ^ (~B21 & B22);
+      A[21] = B21 ^ (~B22 & B23);
+      A[22] = B22 ^ (~B23 & B24);
+      A[23] = B23 ^ (~B24 & B20);
+      A[24] = B24 ^ (~B20 & B21);
+
+      A[0] ^= RC[i];
+      }
+   }
+
+}
+
+Keccak_1600::Keccak_1600(size_t output_bits) :
+   output_bits(output_bits),
+   bitrate(1600 - 2*output_bits),
+   diversifier(output_bits / 8),
+   S(25),
+   buffer(bitrate / 8),
+   buf_pos(0)
+   {
+   // We only support the parameters for the SHA-3 proposal
+
+   if(output_bits != 224 && output_bits != 256 &&
+      output_bits != 384 && output_bits != 512)
+      throw Invalid_Argument("Keccak_1600: Invalid output length " +
+                             to_string(output_bits));
+   }
+
+std::string Keccak_1600::name() const
+   {
+   return "Keccak-1600(" + to_string(output_bits) + ")";
+   }
+
+HashFunction* Keccak_1600::clone() const
+   {
+   return new Keccak_1600(output_bits);
+   }
+
+void Keccak_1600::clear()
+   {
+   zeroise(S);
+   zeroise(buffer);
+   buf_pos = 0;
+   }
+
+void Keccak_1600::add_data(const byte input[], size_t length)
+   {
+   if(length == 0)
+      return;
+
+   while(length)
+      {
+      const size_t consumed = std::min(length, buffer.size() - buf_pos);
+      copy_mem(&buffer[buf_pos], input, consumed);
+
+      input += consumed;
+      length -= consumed;
+      buf_pos += consumed;
+
+      if(buf_pos == buffer.size())
+         {
+         for(size_t i = 0; i != buffer.size() / 8; ++i)
+            S[i] ^= load_le<u64bit>(&buffer[0], i);
+
+         keccak_f_1600(&S[0]);
+
+         buf_pos = 0;
+         }
+      }
+   }
+
+void Keccak_1600::final_result(byte output[])
+   {
+   update(0x01);
+   update(diversifier);
+   update(bitrate / 8);
+   update(0x01);
+
+   if(buf_pos)
+      for(size_t i = buf_pos; i != buffer.size(); ++i)
+         update(0x00);
+
+   /*
+   * We never have to run the permutation again because we only support
+   * limited output lengths
+   */
+   for(size_t i = 0; i != output_length(); ++i)
+      output[i] = get_byte(7 - (i % 8), S[i/8]);
+   }
+
+}
diff --git a/src/hash/keccak/keccak.h b/src/hash/keccak/keccak.h
new file mode 100644
index 000000000..62269c9a1
--- /dev/null
+++ b/src/hash/keccak/keccak.h
@@ -0,0 +1,44 @@
+/*
+* Keccak
+* (C) 2010 Jack Lloyd
+*
+* Distributed under the terms of the Botan license
+*/
+
+#ifndef BOTAN_KECCAK_H__
+#define BOTAN_KECCAK_H__
+
+#include <botan/hash.h>
+#include <botan/secmem.h>
+#include <string>
+
+namespace Botan {
+
+/**
+* Keccak[1600], a SHA-3 candidate
+*/
+class BOTAN_DLL Keccak_1600 : public HashFunction
+   {
+   public:
+      Keccak_1600(size_t output_bits = 512);
+
+      size_t hash_block_size() const { return bitrate / 8; }
+      size_t output_length() const { return output_bits / 8; }
+
+      HashFunction* clone() const;
+      std::string name() const;
+      void clear();
+   private:
+      void add_data(const byte input[], size_t length);
+      void final_result(byte out[]);
+
+      size_t output_bits, bitrate;
+      byte diversifier;
+      SecureVector<u64bit> S;
+      SecureVector<byte> buffer;
+      size_t buf_pos;
+   };
+
+}
+
+#endif