feat(ads/seo/release): v1.2.0 with live Google Ads, isolated ad profile, ads.txt, and SEO/AEO/GEO optimization

tests/Paca.Tests/Security/VirtualFido2AuthenticatorTests.cs

@@ -0,0 +1,64 @@
+using System;
+using System.Security.Cryptography;
+using System.Text;
+using Paca.Core.Security;
+using Xunit;
+
+namespace Paca.Tests.Security;
+
+public class VirtualFido2AuthenticatorTests
+{
+    [Fact]
+    public void MakeCredential_Generates_Valid_Key_And_CredentialId()
+    {
+        var auth = new VirtualFido2Authenticator();
+        var cred = auth.CreateCredential("paca.app", "user-123", "PacaTester");
+
+        Assert.NotNull(cred);
+        Assert.False(string.IsNullOrWhiteSpace(cred.CredentialId));
+        Assert.NotNull(cred.PublicKeyBytes);
+        Assert.True(cred.PublicKeyBytes.Length > 0);
+        Assert.Equal("paca.app", cred.RpId);
+    }
+
+    [Fact]
+    public void GetAssertion_Produces_Verifiable_Signature()
+    {
+        var auth = new VirtualFido2Authenticator();
+        var cred = auth.CreateCredential("login.chanpaca.net", "user-456", "Alice");
+
+        byte[] clientDataHash = SHA256.HashData(Encoding.UTF8.GetBytes("{\"challenge\":\"random-nonce-12345\"}"));
+        var assertion = auth.SignChallenge(cred.CredentialId, clientDataHash);
+
+        Assert.NotNull(assertion);
+        Assert.Equal(cred.CredentialId, assertion.CredentialId);
+        Assert.NotNull(assertion.Signature);
+        Assert.NotNull(assertion.AuthenticatorData);
+
+        // 검증 성공 확인
+        bool isValid = auth.VerifyAssertion(cred.CredentialId, clientDataHash, assertion.AuthenticatorData, assertion.Signature);
+        Assert.True(isValid, "유효한 FIDO2 어설션 서명은 검증에 통과해야 합니다.");
+    }
+
+    [Fact]
+    public void VerifyAssertion_Fails_When_Data_Tampered()
+    {
+        var auth = new VirtualFido2Authenticator();
+        var cred = auth.CreateCredential("login.chanpaca.net", "user-789", "Bob");
+
+        byte[] clientDataHash = SHA256.HashData(Encoding.UTF8.GetBytes("original challenge"));
+        var assertion = auth.SignChallenge(cred.CredentialId, clientDataHash);
+
+        byte[] tamperedHash = SHA256.HashData(Encoding.UTF8.GetBytes("tampered challenge"));
+        bool isValid = auth.VerifyAssertion(cred.CredentialId, tamperedHash, assertion.AuthenticatorData, assertion.Signature);
+        Assert.False(isValid, "변조된 clientDataHash에 대한 서명 검증은 반드시 실패해야 합니다.");
+    }
+
+    [Fact]
+    public void NonExistentCredential_Throws_Or_Returns_Null()
+    {
+        var auth = new VirtualFido2Authenticator();
+        byte[] dummyHash = new byte[32];
+        Assert.Throws<InvalidOperationException>(() => { auth.SignChallenge("non-existent-cred-id", dummyHash); });
+    }
+}