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authorlloyd <[email protected]>2014-01-10 03:41:59 +0000
committerlloyd <[email protected]>2014-01-10 03:41:59 +0000
commit6894dca64c04936d07048c0e8cbf7e25858548c3 (patch)
tree5d572bfde9fe667dab14e3f04b5285a85d8acd95 /src/lib/utils/xor_buf.h
parent9efa3be92442afb3d0b69890a36c7f122df18eda (diff)
Move lib into src
Diffstat (limited to 'src/lib/utils/xor_buf.h')
-rw-r--r--src/lib/utils/xor_buf.h113
1 files changed, 113 insertions, 0 deletions
diff --git a/src/lib/utils/xor_buf.h b/src/lib/utils/xor_buf.h
new file mode 100644
index 000000000..5773a619c
--- /dev/null
+++ b/src/lib/utils/xor_buf.h
@@ -0,0 +1,113 @@
+/*
+* XOR operations
+* (C) 1999-2008 Jack Lloyd
+*
+* Distributed under the terms of the Botan license
+*/
+
+#ifndef BOTAN_XOR_BUF_H__
+#define BOTAN_XOR_BUF_H__
+
+#include <botan/types.h>
+#include <vector>
+
+namespace Botan {
+
+/**
+* XOR arrays. Postcondition out[i] = in[i] ^ out[i] forall i = 0...length
+* @param out the input/output buffer
+* @param in the read-only input buffer
+* @param length the length of the buffers
+*/
+inline void xor_buf(byte out[], const byte in[], size_t length)
+ {
+ while(length >= 8)
+ {
+#if BOTAN_TARGET_UNALIGNED_MEMORY_ACCESS_OK
+ *reinterpret_cast<u64bit*>(out) ^= *reinterpret_cast<const u64bit*>(in);
+#else
+ out[0] ^= in[0]; out[1] ^= in[1];
+ out[2] ^= in[2]; out[3] ^= in[3];
+ out[4] ^= in[4]; out[5] ^= in[5];
+ out[6] ^= in[6]; out[7] ^= in[7];
+#endif
+
+ out += 8; in += 8; length -= 8;
+ }
+
+ for(size_t i = 0; i != length; ++i)
+ out[i] ^= in[i];
+ }
+
+/**
+* XOR arrays. Postcondition out[i] = in[i] ^ in2[i] forall i = 0...length
+* @param out the output buffer
+* @param in the first input buffer
+* @param in2 the second output buffer
+* @param length the length of the three buffers
+*/
+inline void xor_buf(byte out[],
+ const byte in[],
+ const byte in2[],
+ size_t length)
+ {
+ while(length >= 8)
+ {
+#if BOTAN_TARGET_UNALIGNED_MEMORY_ACCESS_OK
+ *reinterpret_cast<u64bit*>(out) =
+ *reinterpret_cast<const u64bit*>(in) ^
+ *reinterpret_cast<const u64bit*>(in2);
+#else
+ out[0] = in[0] ^ in2[0]; out[1] = in[1] ^ in2[1];
+ out[2] = in[2] ^ in2[2]; out[3] = in[3] ^ in2[3];
+ out[4] = in[4] ^ in2[4]; out[5] = in[5] ^ in2[5];
+ out[6] = in[6] ^ in2[6]; out[7] = in[7] ^ in2[7];
+#endif
+
+ in += 8; in2 += 8; out += 8; length -= 8;
+ }
+
+ for(size_t i = 0; i != length; ++i)
+ out[i] = in[i] ^ in2[i];
+ }
+
+template<typename Alloc, typename Alloc2>
+void xor_buf(std::vector<byte, Alloc>& out,
+ const std::vector<byte, Alloc2>& in,
+ size_t n)
+ {
+ xor_buf(&out[0], &in[0], n);
+ }
+
+template<typename Alloc>
+void xor_buf(std::vector<byte, Alloc>& out,
+ const byte* in,
+ size_t n)
+ {
+ xor_buf(&out[0], in, n);
+ }
+
+template<typename Alloc, typename Alloc2>
+void xor_buf(std::vector<byte, Alloc>& out,
+ const byte* in,
+ const std::vector<byte, Alloc2>& in2,
+ size_t n)
+ {
+ xor_buf(&out[0], &in[0], &in2[0], n);
+ }
+
+template<typename T, typename Alloc, typename Alloc2>
+std::vector<T, Alloc>&
+operator^=(std::vector<T, Alloc>& out,
+ const std::vector<T, Alloc2>& in)
+ {
+ if(out.size() < in.size())
+ out.resize(in.size());
+
+ xor_buf(&out[0], &in[0], in.size());
+ return out;
+ }
+
+}
+
+#endif