diff options
| author | Vadim Dashevskiy <watcherhd@gmail.com> | 2012-05-15 10:38:20 +0000 |
|---|---|---|
| committer | Vadim Dashevskiy <watcherhd@gmail.com> | 2012-05-15 10:38:20 +0000 |
| commit | 48540940b6c28bb4378abfeb500ec45a625b37b6 (patch) | |
| tree | 2ef294c0763e802f91d868bdef4229b6868527de /plugins/CryptoPP/crypto/gf256.cpp | |
| parent | 5c350913f011e119127baeb32a6aedeb4f0d33bc (diff) | |
initial commit
git-svn-id: http://svn.miranda-ng.org/main/trunk@2 1316c22d-e87f-b044-9b9b-93d7a3e3ba9c
Diffstat (limited to 'plugins/CryptoPP/crypto/gf256.cpp')
| -rw-r--r-- | plugins/CryptoPP/crypto/gf256.cpp | 34 |
1 files changed, 34 insertions, 0 deletions
diff --git a/plugins/CryptoPP/crypto/gf256.cpp b/plugins/CryptoPP/crypto/gf256.cpp new file mode 100644 index 0000000000..3649f75592 --- /dev/null +++ b/plugins/CryptoPP/crypto/gf256.cpp @@ -0,0 +1,34 @@ +// gf256.cpp - written and placed in the public domain by Wei Dai
+
+#include "pch.h"
+#include "gf256.h"
+
+NAMESPACE_BEGIN(CryptoPP)
+
+GF256::Element GF256::Multiply(Element a, Element b) const
+{
+ word result = 0, t = b;
+
+ for (unsigned int i=0; i<8; i++)
+ {
+ result <<= 1;
+ if (result & 0x100)
+ result ^= m_modulus;
+
+ t <<= 1;
+ if (t & 0x100)
+ result ^= a;
+ }
+
+ return (GF256::Element) result;
+}
+
+GF256::Element GF256::MultiplicativeInverse(Element a) const
+{
+ Element result = a;
+ for (int i=1; i<7; i++)
+ result = Multiply(Square(result), a);
+ return Square(result);
+}
+
+NAMESPACE_END
|