#if !BESTHTTP_DISABLE_ALTERNATE_SSL && (!UNITY_WEBGL || UNITY_EDITOR) #pragma warning disable using System; using System.Runtime.CompilerServices; #if NETCOREAPP2_1_OR_GREATER || NETSTANDARD2_1_OR_GREATER || UNITY_2021_2_OR_NEWER using System.Buffers.Binary; using System.Runtime.InteropServices; #endif #if NETCOREAPP3_0_OR_GREATER using System.Runtime.InteropServices; using System.Runtime.Intrinsics; using System.Runtime.Intrinsics.X86; #endif using Best.HTTP.Shared.PlatformSupport.Memory; using Best.HTTP.SecureProtocol.Org.BouncyCastle.Crypto; using Best.HTTP.SecureProtocol.Org.BouncyCastle.Crypto.Macs; using Best.HTTP.SecureProtocol.Org.BouncyCastle.Crypto.Modes; using Best.HTTP.SecureProtocol.Org.BouncyCastle.Crypto.Modes.Gcm; using Best.HTTP.SecureProtocol.Org.BouncyCastle.Crypto.Parameters; using Best.HTTP.SecureProtocol.Org.BouncyCastle.Crypto.Utilities; using Best.HTTP.SecureProtocol.Org.BouncyCastle.Utilities; namespace Best.HTTP.Shared.TLS.Crypto.Impl { /// /// Implements the Galois/Counter mode (GCM) detailed in NIST Special Publication 800-38D. /// [Best.HTTP.Shared.PlatformSupport.IL2CPP.Il2CppEagerStaticClassConstructionAttribute] #if BESTHTTP_WITH_BURST [Unity.Burst.BurstCompile] #endif public sealed class FastGcmBlockCipher : IAeadBlockCipher { private static IGcmMultiplier CreateGcmMultiplier() { #if NETCOREAPP3_0_OR_GREATER // TODO Prefer more tightly coupled test if (Pclmulqdq.IsSupported) { return new BasicGcmMultiplier(); } #endif return new Tables8kGcmMultiplier(); } public const int BlockSize = 16; byte[] ctrBlock = new byte[BlockSize]; private readonly IBlockCipher cipher; private readonly BurstTables8kGcmMultiplier multiplier; private IGcmExponentiator exp; // These fields are set by Init and not modified by processing private bool forEncryption; private bool initialised; private int macSize; private byte[] lastKey; private byte[] nonce; private byte[] initialAssociatedText; private byte[] H; private byte[] J0; // These fields are modified during processing private byte[] bufBlock; private byte[] macBlock; private byte[] S, S_at, S_atPre; private byte[] counter; private uint counter32; private uint blocksRemaining; private int bufOff; private ulong totalLength; private byte[] atBlock; private int atBlockPos; private ulong atLength; private ulong atLengthPre; public FastGcmBlockCipher( IBlockCipher c) : this(c, null) { } public FastGcmBlockCipher( IBlockCipher c, IGcmMultiplier m) { if (c.GetBlockSize() != BlockSize) throw new ArgumentException("cipher required with a block size of " + BlockSize + "."); //if (m == null) //{ // m = CreateGcmMultiplier(); //} this.cipher = c; this.multiplier = new BurstTables8kGcmMultiplier(); } public string AlgorithmName => cipher.AlgorithmName + "/GCM"; public IBlockCipher UnderlyingCipher => cipher; public int GetBlockSize() { return BlockSize; } /// /// MAC sizes from 32 bits to 128 bits (must be a multiple of 8) are supported. The default is 128 bits. /// Sizes less than 96 are not recommended, but are supported for specialized applications. /// public void Init(bool forEncryption, ICipherParameters parameters) { this.forEncryption = forEncryption; //this.macBlock = null; if (this.macBlock != null) Array.Clear(this.macBlock, 0, this.macBlock.Length); this.initialised = true; KeyParameter keyParam; byte[] newNonce = null; if (parameters is AeadParameters) { AeadParameters param = (AeadParameters)parameters; newNonce = param.GetNonce(); initialAssociatedText = param.GetAssociatedText(); int macSizeBits = param.MacSize; if (macSizeBits < 32 || macSizeBits > 128 || macSizeBits % 8 != 0) { throw new ArgumentException("Invalid value for MAC size: " + macSizeBits); } macSize = macSizeBits / 8; keyParam = param.Key; } else if (parameters is ParametersWithIV) { ParametersWithIV param = (ParametersWithIV)parameters; newNonce = param.GetIV(); initialAssociatedText = null; macSize = 16; keyParam = (KeyParameter)param.Parameters; } else { throw new ArgumentException("invalid parameters passed to GCM"); } int bufLength = forEncryption ? BlockSize : (BlockSize + macSize); this.bufBlock = new byte[bufLength]; if (newNonce == null || newNonce.Length < 1) { throw new ArgumentException("IV must be at least 1 byte"); } if (forEncryption) { if (nonce != null && Arrays.AreEqual(nonce, newNonce)) { if (keyParam == null) { throw new ArgumentException("cannot reuse nonce for GCM encryption"); } if (lastKey != null && Arrays.AreEqual(lastKey, keyParam.GetKey())) { throw new ArgumentException("cannot reuse nonce for GCM encryption"); } } } nonce = newNonce; if (keyParam != null) { lastKey = keyParam.GetKey(); } // TODO Restrict macSize to 16 if nonce length not 12? // Cipher always used in forward mode // if keyParam is null we're reusing the last key. if (keyParam != null) { cipher.Init(true, keyParam); this.H = new byte[BlockSize]; cipher.ProcessBlock(H, 0, H, 0); // if keyParam is null we're reusing the last key and the multiplier doesn't need re-init multiplier.Init(H); exp = null; } else if (this.H == null) { throw new ArgumentException("Key must be specified in initial init"); } this.J0 = new byte[BlockSize]; if (nonce.Length == 12) { Array.Copy(nonce, 0, J0, 0, nonce.Length); this.J0[BlockSize - 1] = 0x01; } else { gHASH(J0, nonce, nonce.Length); byte[] X = new byte[BlockSize]; Pack.UInt64_To_BE((ulong)nonce.Length * 8UL, X, 8); gHASHBlock(J0, X); } this.S = new byte[BlockSize]; this.S_at = new byte[BlockSize]; this.S_atPre = new byte[BlockSize]; this.atBlock = new byte[BlockSize]; this.atBlockPos = 0; this.atLength = 0; this.atLengthPre = 0; this.counter = Arrays.Clone(J0); this.counter32 = Pack.BE_To_UInt32(counter, 12); this.blocksRemaining = uint.MaxValue - 1; // page 8, len(P) <= 2^39 - 256, 1 block used by tag this.bufOff = 0; this.totalLength = 0; if (initialAssociatedText != null) { ProcessAadBytes(initialAssociatedText, 0, initialAssociatedText.Length); } } public byte[] GetMac() { return macBlock == null ? new byte[macSize] : Arrays.Clone(macBlock); } public int GetOutputSize(int len) { int totalData = len + bufOff; if (forEncryption) { return totalData + macSize; } return totalData < macSize ? 0 : totalData - macSize; } public int GetUpdateOutputSize(int len) { int totalData = len + bufOff; if (!forEncryption) { if (totalData < macSize) { return 0; } totalData -= macSize; } return totalData - totalData % BlockSize; } public void ProcessAadByte(byte input) { CheckStatus(); atBlock[atBlockPos] = input; if (++atBlockPos == BlockSize) { // Hash each block as it fills gHASHBlock(S_at, atBlock); atBlockPos = 0; atLength += BlockSize; } } public void ProcessAadBytes(byte[] inBytes, int inOff, int len) { #if NETCOREAPP2_1_OR_GREATER || NETSTANDARD2_1_OR_GREATER || UNITY_2021_2_OR_NEWER ProcessAadBytes(inBytes.AsSpan(inOff, len)); #else CheckStatus(); if (atBlockPos > 0) { int available = BlockSize - atBlockPos; if (len < available) { Array.Copy(inBytes, inOff, atBlock, atBlockPos, len); atBlockPos += len; return; } Array.Copy(inBytes, inOff, atBlock, atBlockPos, available); gHASHBlock(S_at, atBlock); atLength += BlockSize; inOff += available; len -= available; //atBlockPos = 0; } int inLimit = inOff + len - BlockSize; while (inOff <= inLimit) { gHASHBlock(S_at, inBytes, inOff); atLength += BlockSize; inOff += BlockSize; } atBlockPos = BlockSize + inLimit - inOff; Array.Copy(inBytes, inOff, atBlock, 0, atBlockPos); #endif } #if NETCOREAPP2_1_OR_GREATER || NETSTANDARD2_1_OR_GREATER || UNITY_2021_2_OR_NEWER public void ProcessAadBytes(ReadOnlySpan input) { CheckStatus(); if (atBlockPos > 0) { int available = BlockSize - atBlockPos; if (input.Length < available) { input.CopyTo(atBlock.AsSpan(atBlockPos)); atBlockPos += input.Length; return; } input[..available].CopyTo(atBlock.AsSpan(atBlockPos)); gHASHBlock(S_at, atBlock); atLength += BlockSize; input = input[available..]; //atBlockPos = 0; } while (input.Length >= BlockSize) { gHASHBlock(S_at, input); atLength += BlockSize; input = input[BlockSize..]; } input.CopyTo(atBlock); atBlockPos = input.Length; } #endif private void InitCipher() { if (atLength > 0) { Array.Copy(S_at, 0, S_atPre, 0, BlockSize); atLengthPre = atLength; } // Finish hash for partial AAD block if (atBlockPos > 0) { gHASHPartial(S_atPre, atBlock, 0, atBlockPos); atLengthPre += (uint)atBlockPos; } if (atLengthPre > 0) { Array.Copy(S_atPre, 0, S, 0, BlockSize); } } public int ProcessByte(byte input, byte[] output, int outOff) { CheckStatus(); bufBlock[bufOff] = input; if (++bufOff == bufBlock.Length) { if (forEncryption) { #if NETCOREAPP2_1_OR_GREATER || NETSTANDARD2_1_OR_GREATER || UNITY_2021_2_OR_NEWER EncryptBlock(bufBlock, output.AsSpan(outOff)); #else EncryptBlock(bufBlock, 0, output, outOff); #endif bufOff = 0; } else { #if NETCOREAPP2_1_OR_GREATER || NETSTANDARD2_1_OR_GREATER || UNITY_2021_2_OR_NEWER DecryptBlock(bufBlock, output.AsSpan(outOff)); #else DecryptBlock(bufBlock, 0, output, outOff); #endif Array.Copy(bufBlock, BlockSize, bufBlock, 0, macSize); bufOff = macSize; } return BlockSize; } return 0; } #if NETCOREAPP2_1_OR_GREATER || NETSTANDARD2_1_OR_GREATER || UNITY_2021_2_OR_NEWER public int ProcessByte(byte input, Span output) { CheckStatus(); bufBlock[bufOff] = input; if (++bufOff == bufBlock.Length) { if (forEncryption) { EncryptBlock(bufBlock, output); bufOff = 0; } else { DecryptBlock(bufBlock, output); Array.Copy(bufBlock, BlockSize, bufBlock, 0, macSize); bufOff = macSize; } return BlockSize; } return 0; } #endif public int ProcessBytes(byte[] input, int inOff, int len, byte[] output, int outOff) { CheckStatus(); Check.DataLength(input, inOff, len, "input buffer too short"); #if NETCOREAPP2_1_OR_GREATER || NETSTANDARD2_1_OR_GREATER || UNITY_2021_2_OR_NEWER return ProcessBytes(input.AsSpan(inOff, len), Spans.FromNullable(output, outOff)); #else int resultLen = 0; if (forEncryption) { if (bufOff > 0) { int available = BlockSize - bufOff; if (len < available) { Array.Copy(input, inOff, bufBlock, bufOff, len); bufOff += len; return 0; } Array.Copy(input, inOff, bufBlock, bufOff, available); EncryptBlock(bufBlock, 0, output, outOff); inOff += available; len -= available; resultLen = BlockSize; //bufOff = 0; } int inLimit1 = inOff + len - BlockSize; int inLimit2 = inLimit1 - BlockSize; while (inOff <= inLimit2) { EncryptBlocks2(input, inOff, output, outOff + resultLen); inOff += BlockSize * 2; resultLen += BlockSize * 2; } if (inOff <= inLimit1) { EncryptBlock(input, inOff, output, outOff + resultLen); inOff += BlockSize; resultLen += BlockSize; } bufOff = BlockSize + inLimit1 - inOff; Array.Copy(input, inOff, bufBlock, 0, bufOff); } else { int available = bufBlock.Length - bufOff; if (len < available) { Array.Copy(input, inOff, bufBlock, bufOff, len); bufOff += len; return 0; } if (bufOff >= BlockSize) { DecryptBlock(bufBlock, 0, output, outOff); Array.Copy(bufBlock, BlockSize, bufBlock, 0, bufOff -= BlockSize); resultLen = BlockSize; available += BlockSize; if (len < available) { Array.Copy(input, inOff, bufBlock, bufOff, len); bufOff += len; return resultLen; } } int inLimit1 = inOff + len - bufBlock.Length; int inLimit2 = inLimit1 - BlockSize; available = BlockSize - bufOff; Array.Copy(input, inOff, bufBlock, bufOff, available); DecryptBlock(bufBlock, 0, output, outOff + resultLen); inOff += available; resultLen += BlockSize; //bufOff = 0; while (inOff <= inLimit2) { DecryptBlocks2(input, inOff, output, outOff + resultLen); inOff += BlockSize * 2; resultLen += BlockSize * 2; } if (inOff <= inLimit1) { DecryptBlock(input, inOff, output, outOff + resultLen); inOff += BlockSize; resultLen += BlockSize; } bufOff = bufBlock.Length + inLimit1 - inOff; Array.Copy(input, inOff, bufBlock, 0, bufOff); } return resultLen; #endif } #if NETCOREAPP2_1_OR_GREATER || NETSTANDARD2_1_OR_GREATER || UNITY_2021_2_OR_NEWER public unsafe int ProcessBytes(ReadOnlySpan input, Span output) { CheckStatus(); int resultLen = 0; if (forEncryption) { if (bufOff > 0) { int available = BlockSize - bufOff; if (input.Length < available) { input.CopyTo(bufBlock.AsSpan(bufOff)); bufOff += input.Length; return 0; } input[..available].CopyTo(bufBlock.AsSpan(bufOff)); EncryptBlock(bufBlock, output); input = input[available..]; resultLen = BlockSize; //bufOff = 0; } while (input.Length >= BlockSize * 2) { EncryptBlocks2(input, output[resultLen..]); input = input[(BlockSize * 2)..]; resultLen += BlockSize * 2; } if (input.Length >= BlockSize) { EncryptBlock(input, output[resultLen..]); input = input[BlockSize..]; resultLen += BlockSize; } bufOff = input.Length; input.CopyTo(bufBlock); } else { int available = bufBlock.Length - bufOff; if (input.Length < available) { input.CopyTo(bufBlock.AsSpan(bufOff)); bufOff += input.Length; return 0; } if (bufOff >= BlockSize) { DecryptBlock(bufBlock, output); Array.Copy(bufBlock, BlockSize, bufBlock, 0, bufOff -= BlockSize); resultLen = BlockSize; available += BlockSize; if (input.Length < available) { input.CopyTo(bufBlock.AsSpan(bufOff)); bufOff += input.Length; return resultLen; } } int inLimit1 = bufBlock.Length; int inLimit2 = inLimit1 + BlockSize; available = BlockSize - bufOff; input[..available].CopyTo(bufBlock.AsSpan(bufOff)); DecryptBlock(bufBlock, output[resultLen..]); input = input[available..]; resultLen += BlockSize; //bufOff = 0; while (input.Length >= inLimit2) { //DecryptBlocks2(input, output[resultLen..]); var outputSample = output[resultLen..]; if (totalLength == 0) { InitCipher(); } Span ctrBlock = stackalloc byte[BlockSize]; //GetNextCtrBlock(ctrBlock); if (blocksRemaining == 0) throw new InvalidOperationException("Attempt to process too many blocks"); blocksRemaining--; #if NETCOREAPP2_1_OR_GREATER || NETSTANDARD2_1_OR_GREATER || UNITY_2021_2_OR_NEWER BinaryPrimitives.WriteUInt32BigEndian(counter.AsSpan(12), ++counter32); #else Pack.UInt32_To_BE(++counter32, counter, 12); #endif cipher.ProcessBlock(counter, ctrBlock); ReadOnlySpan uInput = MemoryMarshal.Cast(input); Span uS = MemoryMarshal.Cast(S); ReadOnlySpan uCtrBlock = MemoryMarshal.Cast(ctrBlock); Span uOutput = MemoryMarshal.Cast(outputSample); uS[0] ^= uInput[0]; uOutput[0] = uInput[0] ^ uCtrBlock[0]; uS[1] ^= uInput[1]; uOutput[1] = uInput[1] ^ uCtrBlock[1]; uS[2] ^= uInput[2]; uOutput[2] = uInput[2] ^ uCtrBlock[2]; uS[3] ^= uInput[3]; uOutput[3] = uInput[3] ^ uCtrBlock[3]; multiplier.MultiplyH(S); input = input[BlockSize..]; outputSample = outputSample[BlockSize..]; //GetNextCtrBlock(ctrBlock); if (blocksRemaining == 0) throw new InvalidOperationException("Attempt to process too many blocks"); blocksRemaining--; #if NETCOREAPP2_1_OR_GREATER || NETSTANDARD2_1_OR_GREATER || UNITY_2021_2_OR_NEWER BinaryPrimitives.WriteUInt32BigEndian(counter.AsSpan(12), ++counter32); #else Pack.UInt32_To_BE(++counter32, counter, 12); #endif cipher.ProcessBlock(counter, ctrBlock); uInput = MemoryMarshal.Cast(input); uS = MemoryMarshal.Cast(S); uCtrBlock = MemoryMarshal.Cast(ctrBlock); uOutput = MemoryMarshal.Cast(outputSample); uS[0] ^= uInput[0]; uOutput[0] = uInput[0] ^ uCtrBlock[0]; uS[1] ^= uInput[1]; uOutput[1] = uInput[1] ^ uCtrBlock[1]; uS[2] ^= uInput[2]; uOutput[2] = uInput[2] ^ uCtrBlock[2]; uS[3] ^= uInput[3]; uOutput[3] = uInput[3] ^ uCtrBlock[3]; multiplier.MultiplyH(S); totalLength += BlockSize * 2; //input = input[(BlockSize * 2)..]; input = input[BlockSize..]; resultLen += BlockSize * 2; } if (input.Length >= inLimit1) { DecryptBlock(input, output[resultLen..]); input = input[BlockSize..]; resultLen += BlockSize; } bufOff = input.Length; input.CopyTo(bufBlock); } return resultLen; } #endif public int DoFinal(byte[] output, int outOff) { #if NETCOREAPP2_1_OR_GREATER || NETSTANDARD2_1_OR_GREATER || UNITY_2021_2_OR_NEWER return DoFinal(output.AsSpan(outOff)); #else CheckStatus(); if (totalLength == 0) { InitCipher(); } int extra = bufOff; if (forEncryption) { Check.OutputLength(output, outOff, extra + macSize, "output buffer too short"); } else { if (extra < macSize) throw new InvalidCipherTextException("data too short"); extra -= macSize; Check.OutputLength(output, outOff, extra, "output buffer too short"); } if (extra > 0) { ProcessPartial(bufBlock, 0, extra, output, outOff); } atLength += (uint)atBlockPos; if (atLength > atLengthPre) { /* * Some AAD was sent after the cipher started. We determine the difference b/w the hash value * we actually used when the cipher started (S_atPre) and the final hash value calculated (S_at). * Then we carry this difference forward by multiplying by H^c, where c is the number of (full or * partial) cipher-text blocks produced, and adjust the current hash. */ // Finish hash for partial AAD block if (atBlockPos > 0) { gHASHPartial(S_at, atBlock, 0, atBlockPos); } // Find the difference between the AAD hashes if (atLengthPre > 0) { GcmUtilities.Xor(S_at, S_atPre); } // Number of cipher-text blocks produced long c = (long)(((totalLength * 8) + 127) >> 7); // Calculate the adjustment factor byte[] H_c = new byte[16]; if (exp == null) { exp = new BasicGcmExponentiator(); exp.Init(H); } exp.ExponentiateX(c, H_c); // Carry the difference forward GcmUtilities.Multiply(S_at, H_c); // Adjust the current hash GcmUtilities.Xor(S, S_at); } // Final gHASH byte[] X = new byte[BlockSize]; Pack.UInt64_To_BE(atLength * 8UL, X, 0); Pack.UInt64_To_BE(totalLength * 8UL, X, 8); gHASHBlock(S, X); // T = MSBt(GCTRk(J0,S)) byte[] tag = new byte[BlockSize]; cipher.ProcessBlock(J0, 0, tag, 0); GcmUtilities.Xor(tag, S); int resultLen = extra; // We place into macBlock our calculated value for T this.macBlock = new byte[macSize]; Array.Copy(tag, 0, macBlock, 0, macSize); if (forEncryption) { // Append T to the message Array.Copy(macBlock, 0, output, outOff + bufOff, macSize); resultLen += macSize; } else { // Retrieve the T value from the message and compare to calculated one byte[] msgMac = new byte[macSize]; Array.Copy(bufBlock, extra, msgMac, 0, macSize); if (!Arrays.ConstantTimeAreEqual(this.macBlock, msgMac)) throw new InvalidCipherTextException("mac check in GCM failed"); } Reset(false); return resultLen; #endif } #if NETCOREAPP2_1_OR_GREATER || NETSTANDARD2_1_OR_GREATER || UNITY_2021_2_OR_NEWER public int DoFinal(Span output) { CheckStatus(); if (totalLength == 0) { InitCipher(); } int extra = bufOff; if (forEncryption) { Check.OutputLength(output, extra + macSize, "output buffer too short"); } else { if (extra < macSize) throw new InvalidCipherTextException("data too short"); extra -= macSize; Check.OutputLength(output, extra, "output buffer too short"); } if (extra > 0) { ProcessPartial(bufBlock.AsSpan(0, extra), output); } atLength += (uint)atBlockPos; if (atLength > atLengthPre) { /* * Some AAD was sent after the cipher started. We determine the difference b/w the hash value * we actually used when the cipher started (S_atPre) and the final hash value calculated (S_at). * Then we carry this difference forward by multiplying by H^c, where c is the number of (full or * partial) cipher-text blocks produced, and adjust the current hash. */ // Finish hash for partial AAD block if (atBlockPos > 0) { gHASHPartial(S_at, atBlock, 0, atBlockPos); } // Find the difference between the AAD hashes if (atLengthPre > 0) { GcmUtilities.Xor(S_at, S_atPre); } // Number of cipher-text blocks produced long c = (long)(((totalLength * 8) + 127) >> 7); // Calculate the adjustment factor byte[] H_c = new byte[16]; if (exp == null) { exp = new BasicGcmExponentiator(); exp.Init(H); } exp.ExponentiateX(c, H_c); // Carry the difference forward GcmUtilities.Multiply(S_at, H_c); // Adjust the current hash GcmUtilities.Xor(S, S_at); } // Final gHASH Span X = stackalloc byte[BlockSize]; Pack.UInt64_To_BE(atLength * 8UL, X); Pack.UInt64_To_BE(totalLength * 8UL, X[8..]); gHASHBlock(S, X); // T = MSBt(GCTRk(J0,S)) Span tag = stackalloc byte[BlockSize]; cipher.ProcessBlock(J0, tag); GcmUtilities.Xor(tag, S); int resultLen = extra; // We place into macBlock our calculated value for T this.macBlock = new byte[macSize]; tag[..macSize].CopyTo(macBlock); if (forEncryption) { // Append T to the message macBlock.CopyTo(output[bufOff..]); resultLen += macSize; } else { // Retrieve the T value from the message and compare to calculated one Span msgMac = stackalloc byte[macSize]; bufBlock.AsSpan(extra, macSize).CopyTo(msgMac); if (!Arrays.ConstantTimeAreEqual(this.macBlock, msgMac)) throw new InvalidCipherTextException("mac check in GCM failed"); } Reset(false); return resultLen; } #endif public void Reset() { Reset(true); } private void Reset(bool clearMac) { // note: we do not reset the nonce. S = new byte[BlockSize]; S_at = new byte[BlockSize]; S_atPre = new byte[BlockSize]; atBlock = new byte[BlockSize]; atBlockPos = 0; atLength = 0; atLengthPre = 0; counter = Arrays.Clone(J0); counter32 = Pack.BE_To_UInt32(counter, 12); blocksRemaining = uint.MaxValue - 1; bufOff = 0; totalLength = 0; if (bufBlock != null) { Arrays.Fill(bufBlock, 0); } if (clearMac) { macBlock = null; } if (forEncryption) { initialised = false; } else { if (initialAssociatedText != null) { ProcessAadBytes(initialAssociatedText, 0, initialAssociatedText.Length); } } } #if NETCOREAPP2_1_OR_GREATER || NETSTANDARD2_1_OR_GREATER || UNITY_2021_2_OR_NEWER private void DecryptBlock(ReadOnlySpan input, Span output) { Check.OutputLength(output, BlockSize, "output buffer too short"); if (totalLength == 0) { InitCipher(); } Span ctrBlock = stackalloc byte[BlockSize]; GetNextCtrBlock(ctrBlock); #if BESTHTTP_WITH_BURST FastGcmBlockCipherHelper.DecryptBlock(input, output, ctrBlock, S.AsSpan(), BlockSize); #elif NETCOREAPP3_0_OR_GREATER if (Sse2.IsSupported && Unsafe.SizeOf>() == BlockSize) { var t0 = MemoryMarshal.Read>(input); var t1 = MemoryMarshal.Read>(ctrBlock); var t2 = MemoryMarshal.Read>(S.AsSpan()); t1 = Sse2.Xor(t1, t0); t2 = Sse2.Xor(t2, t0); MemoryMarshal.Write(output, ref t1); MemoryMarshal.Write(S.AsSpan(), ref t2); } else #else { for (int i = 0; i < BlockSize; i += 4) { byte c0 = input[i + 0]; byte c1 = input[i + 1]; byte c2 = input[i + 2]; byte c3 = input[i + 3]; S[i + 0] ^= c0; S[i + 1] ^= c1; S[i + 2] ^= c2; S[i + 3] ^= c3; output[i + 0] = (byte)(c0 ^ ctrBlock[i + 0]); output[i + 1] = (byte)(c1 ^ ctrBlock[i + 1]); output[i + 2] = (byte)(c2 ^ ctrBlock[i + 2]); output[i + 3] = (byte)(c3 ^ ctrBlock[i + 3]); } } #endif multiplier.MultiplyH(S); totalLength += BlockSize; } private void DecryptBlocks2(ReadOnlySpan input, Span outputSample) { Check.OutputLength(outputSample, BlockSize * 2, "output buffer too short"); if (totalLength == 0) { InitCipher(); } Span ctrBlock = stackalloc byte[BlockSize]; GetNextCtrBlock(ctrBlock); for (int i = 0; i < BlockSize; i += 4) { byte c0 = input[i + 0]; byte c1 = input[i + 1]; byte c2 = input[i + 2]; byte c3 = input[i + 3]; S[i + 0] ^= c0; S[i + 1] ^= c1; S[i + 2] ^= c2; S[i + 3] ^= c3; outputSample[i + 0] = (byte)(c0 ^ ctrBlock[i + 0]); outputSample[i + 1] = (byte)(c1 ^ ctrBlock[i + 1]); outputSample[i + 2] = (byte)(c2 ^ ctrBlock[i + 2]); outputSample[i + 3] = (byte)(c3 ^ ctrBlock[i + 3]); } multiplier.MultiplyH(S); input = input[BlockSize..]; outputSample = outputSample[BlockSize..]; GetNextCtrBlock(ctrBlock); for (int i = 0; i < BlockSize; i += 4) { byte c0 = input[i + 0]; byte c1 = input[i + 1]; byte c2 = input[i + 2]; byte c3 = input[i + 3]; S[i + 0] ^= c0; S[i + 1] ^= c1; S[i + 2] ^= c2; S[i + 3] ^= c3; outputSample[i + 0] = (byte)(c0 ^ ctrBlock[i + 0]); outputSample[i + 1] = (byte)(c1 ^ ctrBlock[i + 1]); outputSample[i + 2] = (byte)(c2 ^ ctrBlock[i + 2]); outputSample[i + 3] = (byte)(c3 ^ ctrBlock[i + 3]); } multiplier.MultiplyH(S); totalLength += BlockSize * 2; } private void EncryptBlock(ReadOnlySpan input, Span output) { Check.OutputLength(output, BlockSize, "output buffer too short"); if (totalLength == 0) { InitCipher(); } Span ctrBlock = stackalloc byte[BlockSize]; GetNextCtrBlock(ctrBlock); #if NETCOREAPP3_0_OR_GREATER if (Sse2.IsSupported && Unsafe.SizeOf>() == BlockSize) { var t0 = MemoryMarshal.Read>(input); var t1 = MemoryMarshal.Read>(ctrBlock); var t2 = MemoryMarshal.Read>(S.AsSpan()); t1 = Sse2.Xor(t1, t0); t2 = Sse2.Xor(t2, t1); MemoryMarshal.Write(output, ref t1); MemoryMarshal.Write(S.AsSpan(), ref t2); } else #endif { for (int i = 0; i < BlockSize; i += 4) { byte c0 = (byte)(ctrBlock[i + 0] ^ input[i + 0]); byte c1 = (byte)(ctrBlock[i + 1] ^ input[i + 1]); byte c2 = (byte)(ctrBlock[i + 2] ^ input[i + 2]); byte c3 = (byte)(ctrBlock[i + 3] ^ input[i + 3]); S[i + 0] ^= c0; S[i + 1] ^= c1; S[i + 2] ^= c2; S[i + 3] ^= c3; output[i + 0] = c0; output[i + 1] = c1; output[i + 2] = c2; output[i + 3] = c3; } } multiplier.MultiplyH(S); totalLength += BlockSize; } private void EncryptBlocks2(ReadOnlySpan input, Span output) { Check.OutputLength(output, BlockSize * 2, "Output buffer too short"); if (totalLength == 0) { InitCipher(); } Span ctrBlock = stackalloc byte[BlockSize]; GetNextCtrBlock(ctrBlock); #if NETCOREAPP3_0_OR_GREATER if (Sse2.IsSupported && Unsafe.SizeOf>() == BlockSize) { var t0 = MemoryMarshal.Read>(input); var t1 = MemoryMarshal.Read>(ctrBlock); var t2 = MemoryMarshal.Read>(S.AsSpan()); t1 = Sse2.Xor(t1, t0); t2 = Sse2.Xor(t2, t1); MemoryMarshal.Write(output, ref t1); MemoryMarshal.Write(S.AsSpan(), ref t2); } else #endif { for (int i = 0; i < BlockSize; i += 4) { byte c0 = (byte)(ctrBlock[i + 0] ^ input[i + 0]); byte c1 = (byte)(ctrBlock[i + 1] ^ input[i + 1]); byte c2 = (byte)(ctrBlock[i + 2] ^ input[i + 2]); byte c3 = (byte)(ctrBlock[i + 3] ^ input[i + 3]); S[i + 0] ^= c0; S[i + 1] ^= c1; S[i + 2] ^= c2; S[i + 3] ^= c3; output[i + 0] = c0; output[i + 1] = c1; output[i + 2] = c2; output[i + 3] = c3; } } multiplier.MultiplyH(S); input = input[BlockSize..]; output = output[BlockSize..]; GetNextCtrBlock(ctrBlock); #if NETCOREAPP3_0_OR_GREATER if (Sse2.IsSupported && Unsafe.SizeOf>() == BlockSize) { var t0 = MemoryMarshal.Read>(input); var t1 = MemoryMarshal.Read>(ctrBlock); var t2 = MemoryMarshal.Read>(S.AsSpan()); t1 = Sse2.Xor(t1, t0); t2 = Sse2.Xor(t2, t1); MemoryMarshal.Write(output, ref t1); MemoryMarshal.Write(S.AsSpan(), ref t2); } else #endif { for (int i = 0; i < BlockSize; i += 4) { byte c0 = (byte)(ctrBlock[i + 0] ^ input[i + 0]); byte c1 = (byte)(ctrBlock[i + 1] ^ input[i + 1]); byte c2 = (byte)(ctrBlock[i + 2] ^ input[i + 2]); byte c3 = (byte)(ctrBlock[i + 3] ^ input[i + 3]); S[i + 0] ^= c0; S[i + 1] ^= c1; S[i + 2] ^= c2; S[i + 3] ^= c3; output[i + 0] = c0; output[i + 1] = c1; output[i + 2] = c2; output[i + 3] = c3; } } multiplier.MultiplyH(S); totalLength += BlockSize * 2; } [MethodImpl(MethodImplOptions.AggressiveInlining)] private void GetNextCtrBlock(Span block) { if (blocksRemaining == 0) throw new InvalidOperationException("Attempt to process too many blocks"); blocksRemaining--; Pack.UInt32_To_BE(++counter32, counter, 12); cipher.ProcessBlock(counter, block); } private void ProcessPartial(Span partialBlock, Span output) { Span ctrBlock = stackalloc byte[BlockSize]; GetNextCtrBlock(ctrBlock); if (forEncryption) { GcmUtilities.Xor(partialBlock, ctrBlock, partialBlock.Length); gHASHPartial(S, partialBlock); } else { gHASHPartial(S, partialBlock); GcmUtilities.Xor(partialBlock, ctrBlock, partialBlock.Length); } partialBlock.CopyTo(output); totalLength += (uint)partialBlock.Length; } #else private void DecryptBlock(byte[] inBuf, int inOff, byte[] outBuf, int outOff) { Check.OutputLength(outBuf, outOff, BlockSize, "Output buffer too short"); if (totalLength == 0) { InitCipher(); } //byte[] ctrBlock = new byte[BlockSize]; GetNextCtrBlock(ctrBlock); { for (int i = 0; i < BlockSize; i += 4) { byte c0 = inBuf[inOff + i + 0]; byte c1 = inBuf[inOff + i + 1]; byte c2 = inBuf[inOff + i + 2]; byte c3 = inBuf[inOff + i + 3]; S[i + 0] ^= c0; S[i + 1] ^= c1; S[i + 2] ^= c2; S[i + 3] ^= c3; outBuf[outOff + i + 0] = (byte)(c0 ^ ctrBlock[i + 0]); outBuf[outOff + i + 1] = (byte)(c1 ^ ctrBlock[i + 1]); outBuf[outOff + i + 2] = (byte)(c2 ^ ctrBlock[i + 2]); outBuf[outOff + i + 3] = (byte)(c3 ^ ctrBlock[i + 3]); } } multiplier.MultiplyH(S); totalLength += BlockSize; } private void DecryptBlocks2(byte[] inBuf, int inOff, byte[] outBuf, int outOff) { Check.OutputLength(outBuf, outOff, BlockSize * 2, "Output buffer too short"); if (totalLength == 0) { InitCipher(); } //byte[] ctrBlock = new byte[BlockSize]; GetNextCtrBlock(ctrBlock); { for (int i = 0; i < BlockSize; i += 4) { byte c0 = inBuf[inOff + i + 0]; byte c1 = inBuf[inOff + i + 1]; byte c2 = inBuf[inOff + i + 2]; byte c3 = inBuf[inOff + i + 3]; S[i + 0] ^= c0; S[i + 1] ^= c1; S[i + 2] ^= c2; S[i + 3] ^= c3; outBuf[outOff + i + 0] = (byte)(c0 ^ ctrBlock[i + 0]); outBuf[outOff + i + 1] = (byte)(c1 ^ ctrBlock[i + 1]); outBuf[outOff + i + 2] = (byte)(c2 ^ ctrBlock[i + 2]); outBuf[outOff + i + 3] = (byte)(c3 ^ ctrBlock[i + 3]); } } multiplier.MultiplyH(S); inOff += BlockSize; outOff += BlockSize; GetNextCtrBlock(ctrBlock); { for (int i = 0; i < BlockSize; i += 4) { byte c0 = inBuf[inOff + i + 0]; byte c1 = inBuf[inOff + i + 1]; byte c2 = inBuf[inOff + i + 2]; byte c3 = inBuf[inOff + i + 3]; S[i + 0] ^= c0; S[i + 1] ^= c1; S[i + 2] ^= c2; S[i + 3] ^= c3; outBuf[outOff + i + 0] = (byte)(c0 ^ ctrBlock[i + 0]); outBuf[outOff + i + 1] = (byte)(c1 ^ ctrBlock[i + 1]); outBuf[outOff + i + 2] = (byte)(c2 ^ ctrBlock[i + 2]); outBuf[outOff + i + 3] = (byte)(c3 ^ ctrBlock[i + 3]); } } multiplier.MultiplyH(S); totalLength += BlockSize * 2; } private void EncryptBlock(byte[] inBuf, int inOff, byte[] outBuf, int outOff) { Check.OutputLength(outBuf, outOff, BlockSize, "Output buffer too short"); if (totalLength == 0) { InitCipher(); } //byte[] ctrBlock = new byte[BlockSize]; GetNextCtrBlock(ctrBlock); { for (int i = 0; i < BlockSize; i += 4) { byte c0 = (byte)(ctrBlock[i + 0] ^ inBuf[inOff + i + 0]); byte c1 = (byte)(ctrBlock[i + 1] ^ inBuf[inOff + i + 1]); byte c2 = (byte)(ctrBlock[i + 2] ^ inBuf[inOff + i + 2]); byte c3 = (byte)(ctrBlock[i + 3] ^ inBuf[inOff + i + 3]); S[i + 0] ^= c0; S[i + 1] ^= c1; S[i + 2] ^= c2; S[i + 3] ^= c3; outBuf[outOff + i + 0] = c0; outBuf[outOff + i + 1] = c1; outBuf[outOff + i + 2] = c2; outBuf[outOff + i + 3] = c3; } } multiplier.MultiplyH(S); totalLength += BlockSize; } private void EncryptBlocks2(byte[] inBuf, int inOff, byte[] outBuf, int outOff) { Check.OutputLength(outBuf, outOff, BlockSize * 2, "Output buffer too short"); if (totalLength == 0) { InitCipher(); } //byte[] ctrBlock = new byte[BlockSize]; GetNextCtrBlock(ctrBlock); { for (int i = 0; i < BlockSize; i += 4) { byte c0 = (byte)(ctrBlock[i + 0] ^ inBuf[inOff + i + 0]); byte c1 = (byte)(ctrBlock[i + 1] ^ inBuf[inOff + i + 1]); byte c2 = (byte)(ctrBlock[i + 2] ^ inBuf[inOff + i + 2]); byte c3 = (byte)(ctrBlock[i + 3] ^ inBuf[inOff + i + 3]); S[i + 0] ^= c0; S[i + 1] ^= c1; S[i + 2] ^= c2; S[i + 3] ^= c3; outBuf[outOff + i + 0] = c0; outBuf[outOff + i + 1] = c1; outBuf[outOff + i + 2] = c2; outBuf[outOff + i + 3] = c3; } } multiplier.MultiplyH(S); inOff += BlockSize; outOff += BlockSize; GetNextCtrBlock(ctrBlock); { for (int i = 0; i < BlockSize; i += 4) { byte c0 = (byte)(ctrBlock[i + 0] ^ inBuf[inOff + i + 0]); byte c1 = (byte)(ctrBlock[i + 1] ^ inBuf[inOff + i + 1]); byte c2 = (byte)(ctrBlock[i + 2] ^ inBuf[inOff + i + 2]); byte c3 = (byte)(ctrBlock[i + 3] ^ inBuf[inOff + i + 3]); S[i + 0] ^= c0; S[i + 1] ^= c1; S[i + 2] ^= c2; S[i + 3] ^= c3; outBuf[outOff + i + 0] = c0; outBuf[outOff + i + 1] = c1; outBuf[outOff + i + 2] = c2; outBuf[outOff + i + 3] = c3; } } multiplier.MultiplyH(S); totalLength += BlockSize * 2; } private void GetNextCtrBlock(byte[] block) { if (blocksRemaining == 0) throw new InvalidOperationException("Attempt to process too many blocks"); blocksRemaining--; Pack.UInt32_To_BE(++counter32, counter, 12); cipher.ProcessBlock(counter, 0, block, 0); } private void ProcessPartial(byte[] buf, int off, int len, byte[] output, int outOff) { //byte[] ctrBlock = new byte[BlockSize]; GetNextCtrBlock(ctrBlock); if (forEncryption) { GcmUtilities.Xor(buf, off, ctrBlock, 0, len); gHASHPartial(S, buf, off, len); } else { gHASHPartial(S, buf, off, len); GcmUtilities.Xor(buf, off, ctrBlock, 0, len); } Array.Copy(buf, off, output, outOff, len); totalLength += (uint)len; } #endif private void gHASH(byte[] Y, byte[] b, int len) { for (int pos = 0; pos < len; pos += BlockSize) { int num = System.Math.Min(len - pos, BlockSize); gHASHPartial(Y, b, pos, num); } } #if NETCOREAPP2_1_OR_GREATER || NETSTANDARD2_1_OR_GREATER || UNITY_2021_2_OR_NEWER [MethodImpl(MethodImplOptions.AggressiveInlining)] private void gHASHBlock(byte[] Y, ReadOnlySpan b) { GcmUtilities.Xor(Y, b); multiplier.MultiplyH(Y); } [MethodImpl(MethodImplOptions.AggressiveInlining)] private void gHASHPartial(byte[] Y, ReadOnlySpan b) { GcmUtilities.Xor(Y, b, b.Length); multiplier.MultiplyH(Y); } #else private void gHASHBlock(byte[] Y, byte[] b) { GcmUtilities.Xor(Y, b); multiplier.MultiplyH(Y); } private void gHASHBlock(byte[] Y, byte[] b, int off) { GcmUtilities.Xor(Y, b, off); multiplier.MultiplyH(Y); } #endif [MethodImpl(MethodImplOptions.AggressiveInlining)] private void gHASHPartial(byte[] Y, byte[] b, int off, int len) { GcmUtilities.Xor(Y, b, off, len); multiplier.MultiplyH(Y); } private void CheckStatus() { if (!initialised) { if (forEncryption) { throw new InvalidOperationException("GCM cipher cannot be reused for encryption"); } throw new InvalidOperationException("GCM cipher needs to be initialised"); } } } } #pragma warning restore #endif