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Diffstat (limited to 'wrappers/dotnet/VNLib.Utils.Cryptography.Noscrypt/src/Nip44Util.cs')
| -rw-r--r-- | wrappers/dotnet/VNLib.Utils.Cryptography.Noscrypt/src/Nip44Util.cs | 190 |
1 files changed, 0 insertions, 190 deletions
diff --git a/wrappers/dotnet/VNLib.Utils.Cryptography.Noscrypt/src/Nip44Util.cs b/wrappers/dotnet/VNLib.Utils.Cryptography.Noscrypt/src/Nip44Util.cs deleted file mode 100644 index 2aebee1..0000000 --- a/wrappers/dotnet/VNLib.Utils.Cryptography.Noscrypt/src/Nip44Util.cs +++ /dev/null @@ -1,190 +0,0 @@ -// Copyright (C) 2024 Vaughn Nugent -// -// This program is free software: you can redistribute it and/or modify -// it under the terms of the GNU Affero General Public License as -// published by the Free Software Foundation, either version 3 of the -// License, or (at your option) any later version. -// -// This program is distributed in the hope that it will be useful, -// but WITHOUT ANY WARRANTY; without even the implied warranty of -// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the -// GNU Affero General Public License for more details. -// -// You should have received a copy of the GNU Affero General Public License -// along with this program. If not, see <https://www.gnu.org/licenses/>. - -using System; -using System.Buffers.Binary; -using System.Runtime.InteropServices; - -using VNLib.Utils.Memory; - -using static VNLib.Utils.Cryptography.Noscrypt.NoscryptLibrary; - -namespace VNLib.Utils.Cryptography.Noscrypt -{ - - /// <summary> - /// Provides a set of utility methods for working with the Noscrypt library - /// </summary> - public static class Nip44Util - { - /// <summary> - /// Calculates the required NIP44 encryption buffer size for - /// the specified input data size - /// </summary> - /// <param name="dataSize">The size (in bytes) of the encoded data to encrypt</param> - /// <returns>The exact size of the padded buffer output</returns> - public static int CalcBufferSize(int dataSize) - { - /* - * Taken from https://github.com/nostr-protocol/nips/blob/master/44.md - * - * Not gonna lie, kinda dumb branches. I guess they want to save space - * with really tiny messages... Dunno, but whatever RTFM - */ - - //Min message size is 32 bytes - int minSize = Math.Max(dataSize, 32); - - //find the next power of 2 that will fit the min size - int nexPower = 1 << ((int)Math.Log2(minSize - 1)) + 1; - - int chunk = nexPower <= 256 ? 32 : nexPower / 8; - - return (chunk * ((int)Math.Floor((double)((minSize - 1) / chunk)) + 1)) + sizeof(ushort); - } - - /// <summary> - /// Calculates the final buffer size required to hold the encrypted data - /// </summary> - /// <param name="dataSize">The size (in bytes) of plaintext data to encrypt</param> - /// <returns>The number of bytes required to store the final nip44 message</returns> - public static int CalcFinalBufferSize(int dataSize) - { - /* version + nonce + payload + mac */ - return CalcBufferSize(dataSize) + NC_ENCRYPTION_NONCE_SIZE + NC_ENCRYPTION_MAC_SIZE + 1; - } - - /// <summary> - /// Formats the plaintext data into a buffer that can be properly encrypted. - /// The output buffer must be zeroed, or can be zeroed using the - /// <paramref name="zeroOutput"/> parameter. Use <see cref="CalcBufferSize(uint)"/> - /// to determine the required output buffer size. - /// </summary> - /// <param name="plaintextData">A buffer containing plaintext data to copy to the output</param> - /// <param name="output">The output data buffer to format</param> - /// <param name="zeroOutput">A value that indicates if the buffer should be zeroed before use</param> - public static void FormatBuffer(ReadOnlySpan<byte> plaintextData, Span<byte> output, bool zeroOutput) - { - //First zero out the buffer - if (zeroOutput) - { - MemoryUtil.InitializeBlock(output); - } - - //Make sure the output buffer is large enough so we dont overrun it - ArgumentOutOfRangeException.ThrowIfLessThan(output.Length, plaintextData.Length + sizeof(ushort), nameof(output)); - - //Write the data size to the first 2 bytes - ushort dataSize = (ushort)plaintextData.Length; - BinaryPrimitives.WriteUInt16BigEndian(output, dataSize); - - //Copy the plaintext data to the output buffer after the data size - MemoryUtil.Memmove( - src: in MemoryMarshal.GetReference(plaintextData), - srcOffset: 0, - dst: ref MemoryMarshal.GetReference(output), - dstOffset: sizeof(ushort), - elementCount: (uint)plaintextData.Length - ); - - //We assume the remaining buffer is zeroed out - } - - public static void WriteNip44Message( - ReadOnlySpan<byte> payloadBuffer, - byte version, - ReadOnlySpan<byte> mac, - Span<byte> outBuffer - ) - { - int requiredBufferSize = CalcFinalBufferSize(payloadBuffer.Length); - - //Make sure the output buffer is large enough so we dont overrun it - ArgumentOutOfRangeException.ThrowIfLessThan(outBuffer.Length, requiredBufferSize, nameof(outBuffer)); - ArgumentOutOfRangeException.ThrowIfLessThan(mac.Length, NC_ENCRYPTION_MAC_SIZE, nameof(mac)); - - //Write the version number to the first byte - outBuffer[0] = version; - - //Copy the payload buffer to the output buffer after the version number - MemoryUtil.Memmove( - src: in MemoryMarshal.GetReference(payloadBuffer), - srcOffset: 0, - dst: ref MemoryMarshal.GetReference(outBuffer), - dstOffset: 1, - elementCount: (uint)payloadBuffer.Length - ); - - //Copy the mac to the end of the output buffer - MemoryUtil.Memmove( - src: in MemoryMarshal.GetReference(mac), - srcOffset: 0, - dst: ref MemoryMarshal.GetReference(outBuffer), - dstOffset: (uint)(requiredBufferSize - NC_ENCRYPTION_MAC_SIZE), - elementCount: NC_ENCRYPTION_MAC_SIZE - ); - } - - public static ReadOnlySpan<byte> GetNonceFromPayload(ReadOnlySpan<byte> message) - { - //The nonce is 32 bytes following the 1st byte version number of the message - return message.Slice(1, NC_ENCRYPTION_NONCE_SIZE); - } - - public static ReadOnlySpan<byte> GetCiphertextFromPayload(ReadOnlySpan<byte> message) - { - //Message is between the nonce and the trailing mac - int payloadSize = message.Length - (1 + NC_ENCRYPTION_NONCE_SIZE + NC_ENCRYPTION_MAC_SIZE); - return message.Slice(1 + NC_ENCRYPTION_NONCE_SIZE, payloadSize); - } - - public static ReadOnlySpan<byte> GetMacFromPayload(ReadOnlySpan<byte> message) - { - //The mac is the last 32 bytes of the message - return message[^NC_ENCRYPTION_MAC_SIZE..]; - } - - public static ReadOnlySpan<byte> GetNonceAndCiphertext(ReadOnlySpan<byte> message) - { - //The nonce is 32 bytes following the 1st byte version number of the message - return message.Slice(1, NC_ENCRYPTION_NONCE_SIZE + GetCiphertextFromPayload(message).Length); - } - - public static byte GetMessageVersion(ReadOnlySpan<byte> message) - { - //The first byte is the message version - return message[0]; - } - - public static ReadOnlySpan<byte> GetPlaintextMessage(ReadOnlySpan<byte> plaintextPayload) - { - ushort ptLength = BinaryPrimitives.ReadUInt16BigEndian(plaintextPayload); - return plaintextPayload.Slice(sizeof(ushort), ptLength); - } - - public static bool IsValidPlaintextMessage(ReadOnlySpan<byte> plaintextPayload) - { - ushort ptLength = BinaryPrimitives.ReadUInt16BigEndian(plaintextPayload); - return ptLength == plaintextPayload.Length - sizeof(ushort); - } - - public static Range GetPlaintextRange(ReadOnlySpan<byte> plaintextPayload) - { - ushort ptLength = BinaryPrimitives.ReadUInt16BigEndian(plaintextPayload); - return new Range(sizeof(ushort), ptLength); - } - } - -} |