From 67709e5361846f75d34630593a0d4be730531890 Mon Sep 17 00:00:00 2001 From: hashlag Date: Mon, 2 Feb 2026 00:52:08 +0300 Subject: [PATCH] Encryptor: Require end of the output span to be indicated explicitly. Usage becomes much less error-prone. --- Chaos/Cipher/Block/Des/DesCrypt.hpp | 15 +++++++- Chaos/Cipher/Block/Encryptor.hpp | 5 ++- ChaosTests/Cipher/DesCryptTests.cpp | 58 ++++++++--------------------- 3 files changed, 31 insertions(+), 47 deletions(-) diff --git a/Chaos/Cipher/Block/Des/DesCrypt.hpp b/Chaos/Cipher/Block/Des/DesCrypt.hpp index d25fd81..9026dcd 100644 --- a/Chaos/Cipher/Block/Des/DesCrypt.hpp +++ b/Chaos/Cipher/Block/Des/DesCrypt.hpp @@ -90,6 +90,16 @@ struct Bitwise *out++ = (value >> (56 - (i * 8))) & Mask<8>(); } } + + template + static void CrunchUInt64(OutputIt outBegin, OutputIt outEnd, uint64_t value) + { + int_fast8_t i = 0; + for (OutputIt out = outBegin; i < 8 && out != outEnd; ++i, ++out) + { + *out = (value >> (56 - (i * 8))) & Mask<8>(); + } + } }; using RawKey = Service::SeArray; @@ -237,7 +247,8 @@ public: { } template - void EncryptBlock(OutputIt out, InputIt inBegin, InputIt inEnd) const + void EncryptBlock(OutputIt outBegin, OutputIt outEnd, + InputIt inBegin, InputIt inEnd) const { RawBlockArray block; @@ -252,7 +263,7 @@ public: block.End()), Schedule_); - Inner_::Bitwise::CrunchUInt64(out, encrypted); + Inner_::Bitwise::CrunchUInt64(outBegin, outEnd, encrypted); } Block EncryptBlock(Block block) const diff --git a/Chaos/Cipher/Block/Encryptor.hpp b/Chaos/Cipher/Block/Encryptor.hpp index 18f9872..ba3f9f5 100644 --- a/Chaos/Cipher/Block/Encryptor.hpp +++ b/Chaos/Cipher/Block/Encryptor.hpp @@ -9,9 +9,10 @@ class Encryptor { public: template - void EncryptBlock(OutputIt out, InputIt inBegin, InputIt inEnd) const + void EncryptBlock(OutputIt outBegin, OutputIt outEnd, + InputIt inBegin, InputIt inEnd) const { - Impl().EncryptBlock(out, inBegin, inEnd); + Impl().EncryptBlock(outBegin, outEnd, inBegin, inEnd); } template diff --git a/ChaosTests/Cipher/DesCryptTests.cpp b/ChaosTests/Cipher/DesCryptTests.cpp index 1df1028..0338c32 100644 --- a/ChaosTests/Cipher/DesCryptTests.cpp +++ b/ChaosTests/Cipher/DesCryptTests.cpp @@ -51,7 +51,7 @@ TEST(DesCryptTests, EncryptTest) DesCrypt::Key desKey(key.begin(), key.end()); DesCrypt::DesEncryptor enc(desKey); - enc.EncryptBlock(result.begin(), data.begin(), data.end()); + enc.EncryptBlock(result.begin(), result.end(), data.begin(), data.end()); return result; } @@ -143,7 +143,7 @@ TEST(DesCryptTests, EncryptShortDataTest) DesCrypt::Key desKey(key.begin(), key.end()); DesCrypt::DesEncryptor enc(desKey); - enc.EncryptBlock(result.begin(), data.begin(), data.end()); + enc.EncryptBlock(result.begin(), result.end(), data.begin(), data.end()); return result; } @@ -177,7 +177,7 @@ TEST(DesCryptTests, EncryptLongDataTest) DesCrypt::Key desKey(key.begin(), key.end()); DesCrypt::DesEncryptor enc(desKey); - enc.EncryptBlock(result.begin(), data.begin(), data.end()); + enc.EncryptBlock(result.begin(), result.end(), data.begin(), data.end()); return result; } @@ -377,62 +377,34 @@ TEST(DesCryptTests, LongKeyTest) TEST(DesCryptTests, OutIteratorUsageEncryptTest) { - struct OutputItMock - { - OutputItMock(size_t & asteriskCalls, size_t & incrementCalls) - : AsteriskCalls_(asteriskCalls) - , IncrementCalls_(incrementCalls) - { } - - uint8_t & operator*() - { - ++AsteriskCalls_; - - static uint8_t dummy = 0; - return dummy; - } - - OutputItMock operator++(int) - { - ++IncrementCalls_; - - return *this; - } - - size_t & AsteriskCalls_; - size_t & IncrementCalls_; - }; - { std::array data = { 0xe5, 0x1a, 0x9f, 0xd4, 0x19, 0xa7, 0x93, 0x44 }; std::array key = { 0xda, 0xec, 0x68, 0xae, 0x83, 0xe0, 0x1e, 0xab }; - size_t asteriskCalls = 0; - size_t incrementCalls = 0; - OutputItMock it(asteriskCalls, incrementCalls); + std::array fact = {}; + // Last 3 bytes should be untouched. + std::array expected = { 0x42, 0x27, 0x88, 0xa6, 0x7b, 0x00, 0x00, 0x00 }; DesCrypt::Key desKey(key.begin(), key.end()); DesCrypt::DesEncryptor enc(desKey); - enc.EncryptBlock(it, data.begin(), data.end()); + enc.EncryptBlock(fact.begin(), fact.end() - 3, data.begin(), data.end()); - ASSERT_EQ(8, asteriskCalls); - ASSERT_EQ(8, incrementCalls); + ASSERT_EQ(fact, expected); } { - std::array data = { 0xe5, 0x1a, 0x9f, 0xd4, 0x19, 0x9f, 0x9f, 0x9f, 0x9f, 0x9f, 0x9f }; + std::array data = { 0xe5, 0x1a, 0x9f, 0xd4, 0x19, 0xa7, 0x93, 0x44, 0x44, 0x44 }; std::array key = { 0xda, 0xec, 0x68, 0xae, 0x83, 0xe0, 0x1e, 0xab }; - size_t asteriskCalls = 0; - size_t incrementCalls = 0; - OutputItMock it(asteriskCalls, incrementCalls); + std::array fact = {}; + // Last 4 bytes should be untouched. + std::array expected = { 0x42, 0x27, 0x88, 0xa6, 0x00, 0x00, 0x00, 0x00 }; DesCrypt::Key desKey(key.begin(), key.end()); DesCrypt::DesEncryptor enc(desKey); - enc.EncryptBlock(it, data.begin(), data.end()); + enc.EncryptBlock(fact.begin(), fact.end() - 4, data.begin(), data.end()); - ASSERT_EQ(8, asteriskCalls); - ASSERT_EQ(8, incrementCalls); + ASSERT_EQ(fact, expected); } } @@ -504,7 +476,7 @@ static std::vector EncryptThroughBase(const Encryptor & enc, std::vector result; result.resize(enc.GetBlockSize(), 0); - enc.EncryptBlock(result.begin(), begin, end); + enc.EncryptBlock(result.begin(), result.end(), begin, end); return result; }