Authentication implementation

WebApp/Authentication/PasswordHashGenerator.cs

@@ -0,0 +1,32 @@
+namespace WebApp.Authentication;
+
+/// <summary>
+/// Utility class for generating BCrypt password hashes for use in User Secrets configuration.
+/// </summary>
+public static class PasswordHashGenerator
+{
+    /// <summary>
+    /// Generates a BCrypt hash for the given password with work factor 11.
+    /// </summary>
+    /// <param name="password">The password to hash</param>
+    /// <returns>BCrypt hash string suitable for storing in User Secrets</returns>
+    public static string GenerateHash(string password)
+    {
+        return BCrypt.Net.BCrypt.HashPassword(password, workFactor: 11);
+    }
+
+    /// <summary>
+    /// Generates hashes for multiple passwords at once.
+    /// </summary>
+    /// <param name="passwords">Dictionary of label/password pairs</param>
+    /// <returns>Dictionary of label/hash pairs</returns>
+    public static Dictionary<string, string> GenerateHashes(Dictionary<string, string> passwords)
+    {
+        var results = new Dictionary<string, string>();
+        foreach (var kvp in passwords)
+        {
+            results[kvp.Key] = GenerateHash(kvp.Value);
+        }
+        return results;
+    }
+}