Refactor ChaCha and ChaChaTLS use a common core

1 files changed, 75 insertions, 112 deletions

diff --git a/chacha.cpp b/chacha.cpp
index 44100ad2..3df5bc6c 100644
--- a/chacha.cpp
+++ b/chacha.cpp
@@ -219,18 +219,7 @@ void ChaCha_OperateKeystream(KeystreamOperation operation,
     } while (iterationCount--);

 }

 

-ANONYMOUS_NAMESPACE_END

-

-NAMESPACE_BEGIN(CryptoPP)

-

-////////////////////////////// Bernstein ChaCha //////////////////////////////

-

-std::string ChaCha_Policy::AlgorithmName() const

-{

-    return std::string("ChaCha")+IntToString(m_rounds);

-}

-

-std::string ChaCha_Policy::AlgorithmProvider() const

+std::string ChaCha_AlgorithmProvider()

 {

 #if (CRYPTOPP_AVX2_AVAILABLE)

     if (HasAVX2())

@@ -259,6 +248,67 @@ std::string ChaCha_Policy::AlgorithmProvider() const
     return "C++";

 }

 

+unsigned int ChaCha_GetAlignment()

+{

+#if (CRYPTOPP_AVX2_AVAILABLE)

+    if (HasAVX2())

+        return 16;

+    else

+#endif

+#if (CRYPTOPP_SSE2_INTRIN_AVAILABLE)

+    if (HasSSE2())

+        return 16;

+    else

+#endif

+#if (CRYPTOPP_ALTIVEC_AVAILABLE)

+    if (HasAltivec())

+        return 16;

+    else

+#endif

+        return GetAlignmentOf<word32>();

+}

+

+unsigned int ChaCha_GetOptimalBlockSize()

+{

+#if (CRYPTOPP_AVX2_AVAILABLE)

+    if (HasAVX2())

+        return 8 * BYTES_PER_ITERATION;

+    else

+#endif

+#if (CRYPTOPP_SSE2_INTRIN_AVAILABLE)

+    if (HasSSE2())

+        return 4*BYTES_PER_ITERATION;

+    else

+#endif

+#if (CRYPTOPP_ARM_NEON_AVAILABLE)

+    if (HasNEON())

+        return 4*BYTES_PER_ITERATION;

+    else

+#endif

+#if (CRYPTOPP_ALTIVEC_AVAILABLE)

+    if (HasAltivec())

+        return 4*BYTES_PER_ITERATION;

+    else

+#endif

+        return BYTES_PER_ITERATION;

+}

+

+ANONYMOUS_NAMESPACE_END

+

+NAMESPACE_BEGIN(CryptoPP)

+

+////////////////////////////// Bernstein ChaCha //////////////////////////////

+

+std::string ChaCha_Policy::AlgorithmName() const

+{

+    return std::string("ChaCha")+IntToString(m_rounds);

+}

+

+std::string ChaCha_Policy::AlgorithmProvider() const

+{

+    return ChaCha_AlgorithmProvider();

+}

+

 void ChaCha_Policy::CipherSetKey(const NameValuePairs &params, const byte *key, size_t length)

 {

     CRYPTOPP_ASSERT(key); CRYPTOPP_ASSERT(length == 16 || length == 32);

@@ -298,47 +348,12 @@ void ChaCha_Policy::SeekToIteration(lword iterationCount)
 

 unsigned int ChaCha_Policy::GetAlignment() const

 {

-#if (CRYPTOPP_AVX2_AVAILABLE)

-    if (HasAVX2())

-        return 16;

-    else

-#endif

-#if (CRYPTOPP_SSE2_INTRIN_AVAILABLE)

-    if (HasSSE2())

-        return 16;

-    else

-#endif

-#if (CRYPTOPP_ALTIVEC_AVAILABLE)

-    if (HasAltivec())

-        return 16;

-    else

-#endif

-        return GetAlignmentOf<word32>();

+    return ChaCha_GetAlignment();

 }

 

 unsigned int ChaCha_Policy::GetOptimalBlockSize() const

 {

-#if (CRYPTOPP_AVX2_AVAILABLE)

-    if (HasAVX2())

-        return 8 * BYTES_PER_ITERATION;

-    else

-#endif

-#if (CRYPTOPP_SSE2_INTRIN_AVAILABLE)

-    if (HasSSE2())

-        return 4*BYTES_PER_ITERATION;

-    else

-#endif

-#if (CRYPTOPP_ARM_NEON_AVAILABLE)

-    if (HasNEON())

-        return 4*BYTES_PER_ITERATION;

-    else

-#endif

-#if (CRYPTOPP_ALTIVEC_AVAILABLE)

-    if (HasAltivec())

-        return 4*BYTES_PER_ITERATION;

-    else

-#endif

-        return BYTES_PER_ITERATION;

+    return ChaCha_GetOptimalBlockSize();

 }

 

 // OperateKeystream always produces a key stream. The key stream is written

@@ -360,31 +375,7 @@ std::string ChaChaTLS_Policy::AlgorithmName() const
 

 std::string ChaChaTLS_Policy::AlgorithmProvider() const

 {

-#if (CRYPTOPP_AVX2_AVAILABLE)

-    if (HasAVX2())

-        return "AVX2";

-    else

-#endif

-#if (CRYPTOPP_SSE2_INTRIN_AVAILABLE)

-    if (HasSSE2())

-        return "SSE2";

-    else

-#endif

-#if (CRYPTOPP_ARM_NEON_AVAILABLE)

-    if (HasNEON())

-        return "NEON";

-    else

-#endif

-#if (CRYPTOPP_POWER7_AVAILABLE)

-    if (HasPower7())

-        return "Power7";

-    else

-#elif (CRYPTOPP_ALTIVEC_AVAILABLE)

-    if (HasAltivec())

-        return "Altivec";

-    else

-#endif

-    return "C++";

+    return ChaCha_AlgorithmProvider();

 }

 

 void ChaChaTLS_Policy::CipherSetKey(const NameValuePairs &params, const byte *key, size_t length)

@@ -437,47 +428,12 @@ void ChaChaTLS_Policy::SeekToIteration(lword iterationCount)
 

 unsigned int ChaChaTLS_Policy::GetAlignment() const

 {

-#if (CRYPTOPP_AVX2_AVAILABLE)

-    if (HasAVX2())

-        return 16;

-    else

-#endif

-#if (CRYPTOPP_SSE2_INTRIN_AVAILABLE)

-    if (HasSSE2())

-        return 16;

-    else

-#endif

-#if (CRYPTOPP_ALTIVEC_AVAILABLE)

-    if (HasAltivec())

-        return 16;

-    else

-#endif

-        return GetAlignmentOf<word32>();

+    return ChaCha_GetAlignment();

 }

 

 unsigned int ChaChaTLS_Policy::GetOptimalBlockSize() const

 {

-#if (CRYPTOPP_AVX2_AVAILABLE)

-    if (HasAVX2())

-        return 8 * BYTES_PER_ITERATION;

-    else

-#endif

-#if (CRYPTOPP_SSE2_INTRIN_AVAILABLE)

-    if (HasSSE2())

-        return 4*BYTES_PER_ITERATION;

-    else

-#endif

-#if (CRYPTOPP_ARM_NEON_AVAILABLE)

-    if (HasNEON())

-        return 4*BYTES_PER_ITERATION;

-    else

-#endif

-#if (CRYPTOPP_ALTIVEC_AVAILABLE)

-    if (HasAltivec())

-        return 4*BYTES_PER_ITERATION;

-    else

-#endif

-        return BYTES_PER_ITERATION;

+    return ChaCha_GetOptimalBlockSize();

 }

 

 // OperateKeystream always produces a key stream. The key stream is written

@@ -486,9 +442,16 @@ unsigned int ChaChaTLS_Policy::GetOptimalBlockSize() const
 void ChaChaTLS_Policy::OperateKeystream(KeystreamOperation operation,

         byte *output, const byte *input, size_t iterationCount)

 {

-    word32 discard;

+    word32 discard=0;

     ChaCha_OperateKeystream(operation, m_state, m_state[12], discard,

             m_rounds, output, input, iterationCount);

+

+    // If this fires it means ChaCha_OperateKeystream generated a carry

+    // that was discarded. The problem is, the RFC does not specify what

+    // should happen when the counter block wraps. All we can do is

+    // inform the user that something bad may happen because we don't

+    // know what we should do.

+    CRYPTOPP_ASSERT(discard==0);

 }

 

 NAMESPACE_END