Add the Arc4 PRNG draft implementation

Chaos/Cipher/Arc4.hpp

@@ -1,9 +1,112 @@
 #ifndef CHAOS_CIPHER_ARC4_HPP
 #define CHAOS_CIPHER_ARC4_HPP
 
+#include <array>
+#include <cstdint>
+#include <vector>
+
+#include "Service/ChaosException.hpp"
+
 namespace Chaos::Cipher::Arc4
 {
 
+class Arc4Gen
+{
+public:
+    Arc4Gen()
+        : IsInitialized_(false)
+    { }
+
+    template<typename InputIt>
+    Arc4Gen(InputIt keyBegin, InputIt keyEnd)
+    {
+        RekeyImpl(keyBegin, keyEnd);
+    }
+
+    template<typename InputIt>
+    void Rekey(InputIt keyBegin, InputIt keyEnd)
+    {
+        RekeyImpl(keyBegin, keyEnd);
+    }
+
+    template<typename OutputIt>
+    void Generate(OutputIt out, uint64_t bytesCount)
+    {
+        EnsureInitialized();
+
+        for (uint64_t cnt = 0; cnt < bytesCount; ++cnt)
+        {
+            Step();
+            *out++ = Lookup_[static_cast<uint8_t>(Lookup_[I_] + Lookup_[J_])];
+        }
+    }
+
+    void Drop(uint64_t bytesCount)
+    {
+        EnsureInitialized();
+
+        for (uint64_t cnt = 0; cnt < bytesCount; ++cnt)
+        {
+            Step();
+        }
+    }
+
+private:
+    bool IsInitialized_;
+
+    uint8_t I_;
+    uint8_t J_;
+    std::array<uint8_t, 256> Lookup_;
+
+    void EnsureInitialized() const
+    {
+        if (!IsInitialized_)
+        {
+            throw Service::ChaosException("Arc4Gen: not initialized");
+        }
+    }
+
+    template<typename InputIt>
+    void RekeyImpl(InputIt keyBegin, InputIt keyEnd)
+    {
+        I_ = 0;
+        J_ = 0;
+
+        for (uint64_t idx = 0; idx < Lookup_.size(); ++idx)
+        {
+            Lookup_[idx] = static_cast<uint8_t>(idx);
+        }
+
+        std::vector<uint8_t> key(keyBegin, keyEnd);
+
+        if (key.size() < 5)
+        {
+            throw Service::ChaosException("Arc4Gen: key is too small");
+        }
+
+        uint8_t a = 0;
+        uint8_t b = 0;
+
+        for (uint64_t idx = 0; idx < Lookup_.size(); ++idx)
+        {
+            a = static_cast<uint8_t>(idx);
+            b = b + Lookup_[a] + key[a % key.size()];
+
+            std::swap(Lookup_[a], Lookup_[b]);
+        }
+
+        IsInitialized_ = true;
+    }
+
+    void Step()
+    {
+        I_ = I_ + 1;
+        J_ = J_ + Lookup_[I_];
+
+        std::swap(Lookup_[I_], Lookup_[J_]);
+    }
+};
+
 } // namespace Chaos::Cipher::Arc4
 
 #endif

Chaos/Service/ChaosException.hpp

@@ -0,0 +1,31 @@
+#ifndef CHAOS_SERVICE_CHAOSEXCEPTION_HPP
+#define CHAOS_SERVICE_CHAOSEXCEPTION_HPP
+
+#include <string>
+
+namespace Chaos::Service
+{
+
+class ChaosException
+{
+public:
+    ChaosException(std::string && message)
+        : Message_(std::move(message))
+    { }
+
+    ChaosException(const std::string & message)
+        : Message_(message)
+    { }
+
+    const std::string & GetMessage() const
+    {
+        return Message_;
+    }
+
+private:
+    std::string Message_;
+};
+
+} // namespace Chaos::Service
+
+#endif

ChaosTests/CMakeLists.txt

@@ -13,7 +13,8 @@ FetchContent_MakeAvailable(googletest)
 
 set(ChaosTests_SOURCE Hash/Md4HasherTests.cpp
                       Hash/Md5HasherTests.cpp
-                      Mac/HmacTests.cpp)
+                      Mac/HmacTests.cpp
+                      Cipher/Arc4Tests.cpp)
 
 add_executable(ChaosTests ${ChaosTests_SOURCE})
 target_link_libraries(ChaosTests gtest gtest_main)

ChaosTests/Cipher/Arc4Tests.cpp

@@ -3,3 +3,353 @@
 #include "Cipher/Arc4.hpp"
 
 using namespace Chaos::Cipher::Arc4;
+
+TEST(Arc4GenTests, RFCTest)
+{
+    Arc4Gen gen;
+
+    // Key: 0x0102030405 (40 bits)
+
+    {
+        uint8_t key[] = { 0x01, 0x02, 0x03, 0x04, 0x05 };
+        gen.Rekey(key, key + std::size(key));
+
+        std::array<uint8_t, 32> expected =
+        {
+            0xb2, 0x39, 0x63, 0x05, 0xf0, 0x3d, 0xc0, 0x27,
+            0xcc, 0xc3, 0x52, 0x4a, 0x0a, 0x11, 0x18, 0xa8,
+            0x69, 0x82, 0x94, 0x4f, 0x18, 0xfc, 0x82, 0xd5,
+            0x89, 0xc4, 0x03, 0xa4, 0x7a, 0x0d, 0x09, 0x19
+        };
+
+        std::array<uint8_t, 32> fact;
+
+        gen.Generate(fact.begin(), fact.size());
+
+        ASSERT_EQ(expected, fact);
+    }
+
+    {
+        uint8_t key[] = { 0x01, 0x02, 0x03, 0x04, 0x05 };
+        gen.Rekey(key, key + std::size(key));
+
+        std::array<uint8_t, 32> expected =
+        {
+            0x28, 0xcb, 0x11, 0x32, 0xc9, 0x6c, 0xe2, 0x86,
+            0x42, 0x1d, 0xca, 0xad, 0xb8, 0xb6, 0x9e, 0xae,
+            0x1c, 0xfc, 0xf6, 0x2b, 0x03, 0xed, 0xdb, 0x64,
+            0x1d, 0x77, 0xdf, 0xcf, 0x7f, 0x8d, 0x8c, 0x93
+        };
+
+        std::array<uint8_t, 32> fact;
+
+        gen.Drop(240);
+        gen.Generate(fact.begin(), fact.size());
+
+        ASSERT_EQ(expected, fact);
+    }
+
+    {
+        uint8_t key[] = { 0x01, 0x02, 0x03, 0x04, 0x05 };
+        gen.Rekey(key, key + std::size(key));
+
+        std::array<uint8_t, 32> expected =
+        {
+            0x42, 0xb7, 0xd0, 0xcd, 0xd9, 0x18, 0xa8, 0xa3,
+            0x3d, 0xd5, 0x17, 0x81, 0xc8, 0x1f, 0x40, 0x41,
+            0x64, 0x59, 0x84, 0x44, 0x32, 0xa7, 0xda, 0x92,
+            0x3c, 0xfb, 0x3e, 0xb4, 0x98, 0x06, 0x61, 0xf6
+        };
+
+        std::array<uint8_t, 32> fact;
+
+        gen.Drop(496);
+        gen.Generate(fact.begin(), fact.size());
+
+        ASSERT_EQ(expected, fact);
+    }
+
+    {
+        uint8_t key[] = { 0x01, 0x02, 0x03, 0x04, 0x05 };
+        gen.Rekey(key, key + std::size(key));
+
+        std::array<uint8_t, 32> expected =
+        {
+            0x45, 0x12, 0x90, 0x48, 0xe6, 0xa0, 0xed, 0x0b,
+            0x56, 0xb4, 0x90, 0x33, 0x8f, 0x07, 0x8d, 0xa5,
+            0x30, 0xab, 0xbc, 0xc7, 0xc2, 0x0b, 0x01, 0x60,
+            0x9f, 0x23, 0xee, 0x2d, 0x5f, 0x6b, 0xb7, 0xdf
+        };
+
+        std::array<uint8_t, 32> fact;
+
+        gen.Drop(1008);
+        gen.Generate(fact.begin(), fact.size());
+
+        ASSERT_EQ(expected, fact);
+    }
+
+    {
+        uint8_t key[] = { 0x01, 0x02, 0x03, 0x04, 0x05 };
+        gen.Rekey(key, key + std::size(key));
+
+        std::array<uint8_t, 32> expected =
+        {
+            0x1e, 0xb1, 0x4a, 0x0c, 0x13, 0xb3, 0xbf, 0x47,
+            0xfa, 0x2a, 0x0b, 0xa9, 0x3a, 0xd4, 0x5b, 0x8b,
+            0xcc, 0x58, 0x2f, 0x8b, 0xa9, 0xf2, 0x65, 0xe2,
+            0xb1, 0xbe, 0x91, 0x12, 0xe9, 0x75, 0xd2, 0xd7
+        };
+
+        std::array<uint8_t, 32> fact;
+
+        gen.Drop(2032);
+        gen.Generate(fact.begin(), fact.size());
+
+        ASSERT_EQ(expected, fact);
+    }
+
+    {
+        uint8_t key[] = { 0x01, 0x02, 0x03, 0x04, 0x05 };
+        gen.Rekey(key, key + std::size(key));
+
+        std::array<uint8_t, 32> expected =
+        {
+            0x06, 0x83, 0x26, 0xa2, 0x11, 0x84, 0x16, 0xd2,
+            0x1f, 0x9d, 0x04, 0xb2, 0xcd, 0x1c, 0xa0, 0x50,
+            0xff, 0x25, 0xb5, 0x89, 0x95, 0x99, 0x67, 0x07,
+            0xe5, 0x1f, 0xbd, 0xf0, 0x8b, 0x34, 0xd8, 0x75
+        };
+
+        std::array<uint8_t, 32> fact;
+
+        gen.Drop(4080);
+        gen.Generate(fact.begin(), fact.size());
+
+        ASSERT_EQ(expected, fact);
+    }
+
+    {
+        uint8_t key[] = { 0x01, 0x02, 0x03, 0x04, 0x05 };
+        gen.Rekey(key, key + std::size(key));
+
+        std::array<uint8_t, 32> expected =
+        {
+            0x06, 0x83, 0x26, 0xa2, 0x11, 0x84, 0x16, 0xd2,
+            0x1f, 0x9d, 0x04, 0xb2, 0xcd, 0x1c, 0xa0, 0x50,
+            0xff, 0x25, 0xb5, 0x89, 0x95, 0x99, 0x67, 0x07,
+            0xe5, 0x1f, 0xbd, 0xf0, 0x8b, 0x34, 0xd8, 0x75
+        };
+
+        std::array<uint8_t, 32> fact;
+
+        gen.Drop(4080);
+        gen.Generate(fact.begin(), fact.size());
+
+        ASSERT_EQ(expected, fact);
+    }
+
+    // Key: 0x0102030405060708090a (80 bits)
+
+    {
+        uint8_t key[] =
+        {
+            0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07,
+            0x08, 0x09, 0x0a
+        };
+
+        gen.Rekey(key, key + std::size(key));
+
+        std::array<uint8_t, 32> expected =
+        {
+            0xed, 0xe3, 0xb0, 0x46, 0x43, 0xe5, 0x86, 0xcc,
+            0x90, 0x7d, 0xc2, 0x18, 0x51, 0x70, 0x99, 0x02,
+            0x03, 0x51, 0x6b, 0xa7, 0x8f, 0x41, 0x3b, 0xeb,
+            0x22, 0x3a, 0xa5, 0xd4, 0xd2, 0xdf, 0x67, 0x11
+        };
+
+        std::array<uint8_t, 32> fact;
+
+        gen.Generate(fact.begin(), fact.size());
+
+        ASSERT_EQ(expected, fact);
+    }
+
+    {
+        uint8_t key[] =
+        {
+            0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07,
+            0x08, 0x09, 0x0a
+        };
+
+        gen.Rekey(key, key + std::size(key));
+
+        std::array<uint8_t, 32> expected =
+        {
+            0xb5, 0x5a, 0x0a, 0x5b, 0x51, 0xa1, 0x2a, 0x8b,
+            0xe3, 0x48, 0x99, 0xc3, 0xe0, 0x47, 0x51, 0x1a,
+            0xd9, 0xa0, 0x9c, 0xea, 0x3c, 0xe7, 0x5f, 0xe3,
+            0x96, 0x98, 0x07, 0x03, 0x17, 0xa7, 0x13, 0x39
+        };
+
+        std::array<uint8_t, 32> fact;
+
+        gen.Drop(2032);
+        gen.Generate(fact.begin(), fact.size());
+
+        ASSERT_EQ(expected, fact);
+    }
+
+    // Key: 0x0102030405060708090a0b0c0d0e0f10 (128 bits)
+
+    {
+        uint8_t key[] =
+        {
+            0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07,
+            0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e,
+            0x0f, 0x10
+        };
+
+        gen.Rekey(key, key + std::size(key));
+
+        std::array<uint8_t, 32> expected =
+        {
+            0x9a, 0xc7, 0xcc, 0x9a, 0x60, 0x9d, 0x1e, 0xf7,
+            0xb2, 0x93, 0x28, 0x99, 0xcd, 0xe4, 0x1b, 0x97,
+            0x52, 0x48, 0xc4, 0x95, 0x90, 0x14, 0x12, 0x6a,
+            0x6e, 0x8a, 0x84, 0xf1, 0x1d, 0x1a, 0x9e, 0x1c
+        };
+
+        std::array<uint8_t, 32> fact;
+
+        gen.Generate(fact.begin(), fact.size());
+
+        ASSERT_EQ(expected, fact);
+    }
+
+    {
+        uint8_t key[] =
+        {
+            0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07,
+            0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e,
+            0x0f, 0x10
+        };
+
+        gen.Rekey(key, key + std::size(key));
+
+        std::array<uint8_t, 32> expected =
+        {
+            0xd0, 0x3d, 0x1b, 0xc0, 0x3c, 0xd3, 0x3d, 0x70,
+            0xdf, 0xf9, 0xfa, 0x5d, 0x71, 0x96, 0x3e, 0xbd,
+            0x8a, 0x44, 0x12, 0x64, 0x11, 0xea, 0xa7, 0x8b,
+            0xd5, 0x1e, 0x8d, 0x87, 0xa8, 0x87, 0x9b, 0xf5
+        };
+
+        std::array<uint8_t, 32> fact;
+
+        gen.Drop(2032);
+        gen.Generate(fact.begin(), fact.size());
+
+        ASSERT_EQ(expected, fact);
+    }
+
+    // Key: 0x0102030405060708090a0b0c0d0e0f101112131415161718191a1b1c1d1e1f20 (256 bits)
+
+    {
+        uint8_t key[] =
+        {
+            0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07,
+            0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e,
+            0x0f, 0x10, 0x11, 0x12, 0x13, 0x14, 0x15,
+            0x16, 0x17, 0x18, 0x19, 0x1a, 0x1b, 0x1c,
+            0x1d, 0x1e, 0x1f, 0x20
+        };
+
+        gen.Rekey(key, key + std::size(key));
+
+        std::array<uint8_t, 32> expected =
+        {
+            0xea, 0xa6, 0xbd, 0x25, 0x88, 0x0b, 0xf9, 0x3d,
+            0x3f, 0x5d, 0x1e, 0x4c, 0xa2, 0x61, 0x1d, 0x91,
+            0xcf, 0xa4, 0x5c, 0x9f, 0x7e, 0x71, 0x4b, 0x54,
+            0xbd, 0xfa, 0x80, 0x02, 0x7c, 0xb1, 0x43, 0x80
+        };
+
+        std::array<uint8_t, 32> fact;
+
+        gen.Generate(fact.begin(), fact.size());
+
+        ASSERT_EQ(expected, fact);
+    }
+
+    {
+        uint8_t key[] =
+        {
+            0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07,
+            0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e,
+            0x0f, 0x10, 0x11, 0x12, 0x13, 0x14, 0x15,
+            0x16, 0x17, 0x18, 0x19, 0x1a, 0x1b, 0x1c,
+            0x1d, 0x1e, 0x1f, 0x20
+        };
+
+        gen.Rekey(key, key + std::size(key));
+
+        std::array<uint8_t, 32> expected =
+        {
+            0xf6, 0x56, 0xab, 0xcc, 0xf8, 0x8d, 0xd8, 0x27,
+            0x02, 0x7b, 0x2c, 0xe9, 0x17, 0xd4, 0x64, 0xec,
+            0x18, 0xb6, 0x25, 0x03, 0xbf, 0xbc, 0x07, 0x7f,
+            0xba, 0xbb, 0x98, 0xf2, 0x0d, 0x98, 0xab, 0x34
+        };
+
+        std::array<uint8_t, 32> fact;
+
+        gen.Drop(2032);
+        gen.Generate(fact.begin(), fact.size());
+
+        ASSERT_EQ(expected, fact);
+    }
+}
+
+TEST(Arc4GenTests, TooSmallKeyTest)
+{
+    {
+        const char * key = "smal";
+
+        Arc4Gen gen;
+        ASSERT_THROW(gen.Rekey(key, key + strlen(key)), Chaos::Service::ChaosException);
+
+        ASSERT_THROW(Arc4Gen(key, key + strlen(key)), Chaos::Service::ChaosException);
+    }
+}
+
+TEST(Arc4GenTests, UninitializedGenTest)
+{
+    std::array<uint8_t, 10> out;
+
+    {
+        Arc4Gen gen;
+
+        ASSERT_THROW(gen.Generate(out.begin(), out.size()), Chaos::Service::ChaosException);
+
+        ASSERT_THROW(gen.Drop(0), Chaos::Service::ChaosException);
+        ASSERT_THROW(gen.Drop(1), Chaos::Service::ChaosException);
+        ASSERT_THROW(gen.Drop(20), Chaos::Service::ChaosException);
+        ASSERT_THROW(gen.Drop(256), Chaos::Service::ChaosException);
+    }
+
+    {
+        const char * key = "smal";
+
+        Arc4Gen gen;
+
+        ASSERT_THROW(gen.Rekey(key, key + strlen(key)), Chaos::Service::ChaosException);
+
+        ASSERT_THROW(gen.Generate(out.begin(), out.size()), Chaos::Service::ChaosException);
+
+        ASSERT_THROW(gen.Drop(0), Chaos::Service::ChaosException);
+        ASSERT_THROW(gen.Drop(1), Chaos::Service::ChaosException);
+        ASSERT_THROW(gen.Drop(20), Chaos::Service::ChaosException);
+        ASSERT_THROW(gen.Drop(256), Chaos::Service::ChaosException);
+    }
+}