PM-20532 - Add KM SendPasswordHasher

src/Core/KeyManagement/Sends/ISendPasswordHasher.cs

@@ -0,0 +1,7 @@
+namespace Bit.Core.KeyManagement.Sends;
+
+public interface ISendPasswordHasher
+{
+    bool VerifyPasswordHash(string sendPasswordHash, string userSubmittedPasswordHash);
+    string HashPasswordHash(string clientHashedPassword);
+}

src/Core/KeyManagement/Sends/SendPasswordHasher.cs

@@ -0,0 +1,29 @@
+using Bit.Core.Entities;
+using Microsoft.AspNetCore.Identity;
+
+namespace Bit.Core.KeyManagement.Sends;
+
+public class SendPasswordHasher(IPasswordHasher<User> passwordHasher) : ISendPasswordHasher
+{
+    /// <summary>
+    /// Verifies an existing send password hash against a new user submitted password hash.
+    /// </summary>
+    public bool VerifyPasswordHash(string sendPasswordHash, string userSubmittedPasswordHash)
+    {
+        if (string.IsNullOrWhiteSpace(sendPasswordHash) || string.IsNullOrWhiteSpace(userSubmittedPasswordHash))
+        {
+            return false;
+        }
+        var passwordResult = passwordHasher.VerifyHashedPassword(new User(), sendPasswordHash, userSubmittedPasswordHash);
+
+        return passwordResult is PasswordVerificationResult.Success or PasswordVerificationResult.SuccessRehashNeeded;
+    }
+
+    /// <summary>
+    /// Accepts a client hashed send password and returns a server hashed password.
+    /// </summary>
+    public string HashPasswordHash(string clientHashedPassword)
+    {
+        return passwordHasher.HashPassword(new User(), clientHashedPassword);
+    }
+}

src/Core/KeyManagement/Sends/SendPasswordServiceCollectionExtensions.cs

@@ -0,0 +1,17 @@
+using Bit.Core.Auth.PasswordValidation;
+using Bit.Core.Entities;
+using Bit.Core.KeyManagement.Sends;
+using Microsoft.AspNetCore.Identity;
+using Microsoft.Extensions.DependencyInjection.Extensions;
+
+namespace Microsoft.Extensions.DependencyInjection;
+
+public static class SendPasswordServiceCollectionExtensions
+{
+    public static void AddSendPasswordServices(this IServiceCollection services)
+    {
+        services.TryAddScoped<IPasswordHasher<User>, PasswordHasher<User>>();
+        services.Configure<PasswordHasherOptions>(options => options.IterationCount = PasswordValidationConstants.PasswordHasherKdfIterations);
+        services.TryAddScoped<ISendPasswordHasher, SendPasswordHasher>();
+    }
+}