Initial commit: scadaproj umbrella — sister-project index, auth component normalization (design + GAPS), and the built ZB.MOM.WW.Auth shared library (0.1.0, flattened in).

2026-06-01 03:59:23 -04:00
commit 37e23cf9f2
73 changed files with 6836 additions and 0 deletions
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+using System.Security.Cryptography;
+using System.Text;
+
+namespace ZB.MOM.WW.Auth.ApiKeys;
+
+internal static class ApiKeySecretHasher
+{
+    /// <summary>
+    /// Computes HMAC-SHA256(key: UTF-8(pepper), data: UTF-8(secret)).
+    /// </summary>
+    public static byte[] Hash(string secret, string pepper)
+    {
+        byte[] pepperBytes = Encoding.UTF8.GetBytes(pepper);
+        byte[] secretBytes = Encoding.UTF8.GetBytes(secret);
+
+        using HMACSHA256 hmac = new(pepperBytes);
+        return hmac.ComputeHash(secretBytes);
+    }
+
+    /// <summary>
+    /// Returns true iff HMAC-SHA256(key: UTF-8(pepper), data: UTF-8(secret)) equals
+    /// <paramref name="expectedHash"/>, using a constant-time comparison.
+    /// Returns false (without throwing) if the lengths differ.
+    /// </summary>
+    public static bool Verify(string secret, string pepper, byte[] expectedHash)
+    {
+        byte[] actualHash = Hash(secret, pepper);
+        return CryptographicOperations.FixedTimeEquals(actualHash, expectedHash);
+    }
+}