feat(crypto): ✨ add PwHash struct and related APIs

Author: jasonboukheir

Runtime/Algorand.Unity.Crypto/PwHash/PwHash+Hash.cs

@@ -0,0 +1,65 @@
+using System;
+
+namespace Algorand.Unity.Crypto
+{
+    public partial struct PwHash
+    {
+        public enum HashAlgorithm
+        {
+            None,
+            Default = sodium.crypto_pwhash_ALG_DEFAULT,
+            Argon2I13 = sodium.crypto_pwhash_ALG_ARGON2I13,
+            Argon2ID13 = sodium.crypto_pwhash_ALG_ARGON2ID13
+        }
+
+        public enum HashError
+        {
+            None = 0,
+            OutOfMemory = -1
+        }
+
+        /// <summary>
+        /// Hash a password with the given salt. If there is an error, the out handle will not be allocated.
+        /// </summary>
+        /// <param name="passwd"></param>
+        /// <param name="salt"></param>
+        /// <param name="outlen"></param>
+        /// <param name="out"></param>
+        /// <param name="alg"></param>
+        /// <param name="opsLimit"></param>
+        /// <param name="memLimit"></param>
+        /// <returns></returns>
+        public static HashError Hash(
+            SodiumString passwd,
+            Salt salt,
+            uint outlen,
+            out SecureMemoryHandle @out,
+            HashAlgorithm alg = HashAlgorithm.Default,
+            OpsLimit opsLimit = OpsLimit.Interactive,
+            MemLimit memLimit = MemLimit.Interactive
+        )
+        {
+            HashError err;
+            @out = SecureMemoryHandle.Create((UIntPtr)outlen);
+            unsafe
+            {
+                err = (HashError)sodium.crypto_pwhash(
+                    (byte*)@out.Ptr,
+                    outlen,
+                    passwd.GetUnsafePtr(),
+                    (ulong)passwd.Length,
+                    salt.bytes,
+                    (ulong)opsLimit,
+                    (UIntPtr)memLimit,
+                    (int)alg
+                );
+            }
+            if (err != HashError.None)
+            {
+                @out.Dispose();
+                @out = default;
+            }
+            return err;
+        }
+    }
+}

Runtime/Algorand.Unity.Crypto/PwHash/PwHash+Hash.cs.meta

@@ -0,0 +1,17 @@
+using System;
+using System.Runtime.InteropServices;
+
+namespace Algorand.Unity.Crypto
+{
+    public partial struct PwHash
+    {
+        [Serializable]
+        [StructLayout(LayoutKind.Explicit, Size = SizeBytes)]
+        public struct Salt
+        {
+            public const int SizeBytes = sodium.crypto_pwhash_SALTBYTES;
+            [FieldOffset(0), NonSerialized] public unsafe fixed byte bytes[SizeBytes];
+            [FieldOffset(0)] public unsafe fixed ulong ulongs[SizeBytes / sizeof(ulong)];
+        }
+    }
+}

Runtime/Algorand.Unity.Crypto/PwHash/PwHash+Salt.cs

@@ -13,7 +13,7 @@ public enum PasswordStorageError
 
     public partial struct PwHash
     {
-        public PasswordStorageError HashStore(SecureString password)
+        public PasswordStorageError HashStore(SodiumString password)
         {
             unsafe
             {
@@ -28,7 +28,7 @@ public PasswordStorageError HashStore(SecureString password)
         }
 
         public static JobHandle HashStore(
-            SecureString password,
+            SodiumString password,
             NativeReference<PwHash> hash,
             JobHandle inputDeps = default
         )
@@ -44,7 +44,7 @@ public static JobHandle HashStore(
         [BurstCompile]
         public struct HashStoreJob : IJob
         {
-            public SecureString Password;
+            public SodiumString Password;
             public NativeReference<PwHash> Hash;
 
             public void Execute()

Runtime/Algorand.Unity.Crypto/PwHash/PwHash+Salt.cs.meta

@@ -8,7 +8,7 @@ public enum PasswordVerificationError
 
     public partial struct PwHash
     {
-        public PasswordVerificationError Verify(SecureString password)
+        public PasswordVerificationError Verify(SodiumString password)
         {
             unsafe
             {

Runtime/Algorand.Unity.Crypto/PwHash/PwHash+Store.cs

@@ -9,6 +9,9 @@ namespace Algorand.Unity.Crypto
     [StructLayout(LayoutKind.Sequential, Size = SizeBytes)]
     public partial struct PwHash
     {
+        public const uint MinLength = sodium.crypto_pwhash_PASSWD_MIN;
+        public const uint MaxLength = sodium.crypto_pwhash_PASSWD_MAX;
+
         public const int SizeBytes = sizeof(ulong)
             + sizeof(ulong)
             + sodium.crypto_pwhash_STRBYTES;
@@ -67,7 +70,7 @@ public byte this[int index]
         [MethodImpl(MethodImplOptions.AggressiveInlining)]
         public unsafe byte* GetUnsafePtr()
         {
-            return (byte*) UnsafeUtility.AddressOf(ref bytes[0]);
+            return (byte*)UnsafeUtility.AddressOf(ref bytes[0]);
         }
 
         [Conditional("ENABLE_UNITY_COLLECTIONS_CHECKS")]