diff options
Diffstat (limited to 'lib/NVault.Crypto.Noscrypt/src/Nip44Util.cs')
| -rw-r--r-- | lib/NVault.Crypto.Noscrypt/src/Nip44Util.cs | 93 |
1 files changed, 76 insertions, 17 deletions
diff --git a/lib/NVault.Crypto.Noscrypt/src/Nip44Util.cs b/lib/NVault.Crypto.Noscrypt/src/Nip44Util.cs index 18762c0..4eb4236 100644 --- a/lib/NVault.Crypto.Noscrypt/src/Nip44Util.cs +++ b/lib/NVault.Crypto.Noscrypt/src/Nip44Util.cs @@ -21,6 +21,7 @@ using VNLib.Utils.Memory; namespace NVault.Crypto.Noscrypt { + /// <summary> /// Provides a set of utility methods for working with the Noscrypt library /// </summary> @@ -32,22 +33,24 @@ namespace NVault.Crypto.Noscrypt /// </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 uint CalcBufferSize(uint dataSize) + public static int CalcBufferSize(int dataSize) { - //always add leading 2 bytes for the encoded data size - dataSize += sizeof(ushort); + /* + * 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 - uint minSize = Math.Max(dataSize, 32); + int minSize = Math.Max(dataSize, 32); - //calculate the next power of 2 - uint nextPow2 = 1; - while (nextPow2 < minSize) - { - nextPow2 <<= 1; - } + //find the next power of 2 that will fit the min size + int nexPower = 1 << ((int)Math.Log2(minSize - 1)) + 1; - return nextPow2; + int chunk = nexPower <= 256 ? 32 : nexPower / 8; + + return chunk * ((int)Math.Floor((double)((minSize - 1) / chunk)) + 1); } /// <summary> @@ -77,9 +80,9 @@ namespace NVault.Crypto.Noscrypt //Copy the plaintext data to the output buffer after the data size MemoryUtil.Memmove( ref MemoryMarshal.GetReference(plaintextData), - sizeof(ushort), + 0, ref MemoryMarshal.GetReference(output), - 0, + sizeof(ushort), (uint)plaintextData.Length ); @@ -92,6 +95,7 @@ namespace NVault.Crypto.Noscrypt ref readonly NCPublicKey publicKey, ReadOnlySpan<byte> nonce32, ReadOnlySpan<byte> plainText, + Span<byte> hmackKeyOut32, Span<byte> cipherText ) { @@ -101,7 +105,9 @@ namespace NVault.Crypto.Noscrypt ArgumentOutOfRangeException.ThrowIfGreaterThan(plainText.Length, cipherText.Length, nameof(plainText)); //Nonce must be exactly 32 bytes - ArgumentOutOfRangeException.ThrowIfNotEqual(nonce32.Length, 32, nameof(nonce32)); + ArgumentOutOfRangeException.ThrowIfNotEqual(nonce32.Length, LibNoscrypt.NC_ENCRYPTION_NONCE_SIZE, nameof(nonce32)); + + ArgumentOutOfRangeException.ThrowIfNotEqual(hmackKeyOut32.Length, LibNoscrypt.NC_HMAC_KEY_SIZE, nameof(hmackKeyOut32)); //Encrypt data, use the plaintext buffer size as the data size lib.Encrypt( @@ -110,7 +116,8 @@ namespace NVault.Crypto.Noscrypt in MemoryMarshal.GetReference(nonce32), in MemoryMarshal.GetReference(plainText), ref MemoryMarshal.GetReference(cipherText), - (uint)plainText.Length + (uint)plainText.Length, + ref MemoryMarshal.GetReference(hmackKeyOut32) ); } @@ -119,6 +126,7 @@ namespace NVault.Crypto.Noscrypt ref NCSecretKey secretKey, ref NCPublicKey publicKey, void* nonce32, + void* hmacKeyOut32, void* plainText, void* cipherText, uint size @@ -133,8 +141,9 @@ namespace NVault.Crypto.Noscrypt lib, in secretKey, in publicKey, - new Span<byte>(nonce32, 32), - new Span<byte>(plainText, (int)size), + new ReadOnlySpan<byte>(nonce32, 32), + new ReadOnlySpan<byte>(plainText, (int)size), + new Span<byte>(hmacKeyOut32, 32), new Span<byte>(cipherText, (int)size) ); } @@ -192,5 +201,55 @@ namespace NVault.Crypto.Noscrypt new Span<byte>(plainText, (int)size) ); } + + public static bool VerifyMac( + this INostrCrypto lib, + ref readonly NCSecretKey secretKey, + ref readonly NCPublicKey publicKey, + ReadOnlySpan<byte> nonce32, + ReadOnlySpan<byte> mac32, + ReadOnlySpan<byte> payload + ) + { + ArgumentNullException.ThrowIfNull(lib); + ArgumentOutOfRangeException.ThrowIfZero(payload.Length, nameof(payload)); + ArgumentOutOfRangeException.ThrowIfNotEqual(nonce32.Length, LibNoscrypt.NC_ENCRYPTION_NONCE_SIZE, nameof(nonce32)); + ArgumentOutOfRangeException.ThrowIfNotEqual(mac32.Length, LibNoscrypt.NC_ENCRYPTION_MAC_SIZE, nameof(mac32)); + + //Verify the HMAC + return lib.VerifyMac( + in secretKey, + in publicKey, + in MemoryMarshal.GetReference(nonce32), + in MemoryMarshal.GetReference(mac32), + in MemoryMarshal.GetReference(payload), + payload.Length + ); + } + + public static unsafe bool VerifyMac( + this INostrCrypto lib, + ref readonly NCSecretKey secretKey, + ref readonly NCPublicKey publicKey, + void* nonce32, + void* mac32, + void* payload, + uint payloadSize + ) + { + ArgumentNullException.ThrowIfNull(nonce32); + ArgumentNullException.ThrowIfNull(mac32); + ArgumentNullException.ThrowIfNull(payload); + + //Spans are easer to forward references from pointers without screwing up arguments + return VerifyMac( + lib, + in secretKey, + in publicKey, + new Span<byte>(nonce32, LibNoscrypt.NC_ENCRYPTION_NONCE_SIZE), + new Span<byte>(mac32, LibNoscrypt.NC_ENCRYPTION_MAC_SIZE), + new Span<byte>(payload, (int)payloadSize) + ); + } } } |