Add webauthn

Gemfile

@@ -31,6 +31,9 @@ gem "rqrcode", "~> 3.1"
 # JWT for OIDC ID tokens
 gem "jwt", "~> 3.1"
 
+# WebAuthn for passkey support
+gem "webauthn", "~> 3.0"
+
 # Public Suffix List for domain parsing
 gem "public_suffix", "~> 6.0"
 

Gemfile.lock

@@ -77,11 +77,13 @@ GEM
       uri (>= 0.13.1)
     addressable (2.8.7)
       public_suffix (>= 2.0.2, < 7.0)
+    android_key_attestation (0.3.0)
     ast (2.4.3)
     base64 (0.3.0)
     bcrypt (3.1.20)
     bcrypt_pbkdf (1.1.1)
     bigdecimal (3.3.1)
+    bindata (2.5.1)
     bindex (0.8.1)
     bootsnap (1.18.6)
       msgpack (~> 1.2)
@@ -100,11 +102,15 @@ GEM
       rack-test (>= 0.6.3)
       regexp_parser (>= 1.5, < 3.0)
       xpath (~> 3.2)
+    cbor (0.5.10.1)
     childprocess (5.1.0)
       logger (~> 1.5)
     chunky_png (1.4.0)
     concurrent-ruby (1.3.5)
     connection_pool (2.5.4)
+    cose (1.3.1)
+      cbor (~> 0.5.9)
+      openssl-signature_algorithm (~> 1.0)
     crass (1.0.6)
     date (3.4.1)
     debug (1.11.0)
@@ -209,6 +215,9 @@ GEM
       racc (~> 1.4)
     nokogiri (1.18.10-x86_64-linux-musl)
       racc (~> 1.4)
+    openssl (3.3.2)
+    openssl-signature_algorithm (1.3.0)
+      openssl (> 2.0)
     ostruct (0.6.3)
     parallel (1.27.0)
     parser (3.3.9.0)
@@ -315,6 +324,8 @@ GEM
       ffi (~> 1.12)
       logger
     rubyzip (3.2.1)
+    safety_net_attestation (0.5.0)
+      jwt (>= 2.0, < 4.0)
     securerandom (0.4.1)
     selenium-webdriver (4.38.0)
       base64 (~> 0.2)
@@ -363,6 +374,10 @@ GEM
     thruster (0.1.16-arm64-darwin)
     thruster (0.1.16-x86_64-linux)
     timeout (0.4.3)
+    tpm-key_attestation (0.14.1)
+      bindata (~> 2.4)
+      openssl (> 2.0)
+      openssl-signature_algorithm (~> 1.0)
     tsort (0.2.0)
     turbo-rails (2.0.17)
       actionpack (>= 7.1.0)
@@ -379,6 +394,14 @@ GEM
       activemodel (>= 6.0.0)
       bindex (>= 0.4.0)
       railties (>= 6.0.0)
+    webauthn (3.4.3)
+      android_key_attestation (~> 0.3.0)
+      bindata (~> 2.4)
+      cbor (~> 0.5.9)
+      cose (~> 1.1)
+      openssl (>= 2.2)
+      safety_net_attestation (~> 0.5.0)
+      tpm-key_attestation (~> 0.14.0)
     websocket (1.2.11)
     websocket-driver (0.8.0)
       base64
@@ -429,6 +452,7 @@ DEPENDENCIES
   turbo-rails
   tzinfo-data
   web-console
+  webauthn (~> 3.0)
 
 BUNDLED WITH
    2.7.2

app/controllers/sessions_controller.rb

@@ -1,7 +1,8 @@
 class SessionsController < ApplicationController
-  allow_unauthenticated_access only: %i[ new create verify_totp ]
+  allow_unauthenticated_access only: %i[ new create verify_totp webauthn_challenge webauthn_verify ]
   rate_limit to: 20, within: 3.minutes, only: :create, with: -> { redirect_to signin_path, alert: "Too many attempts. Try again later." }
   rate_limit to: 10, within: 3.minutes, only: :verify_totp, with: -> { redirect_to totp_verification_path, alert: "Too many attempts. Try again later." }
+  rate_limit to: 10, within: 3.minutes, only: [:webauthn_challenge, :webauthn_verify], with: -> { render json: { error: "Too many attempts. Try again later." }, status: :too_many_requests }
 
   def new
     # Redirect to signup if this is first run
@@ -118,6 +119,141 @@ class SessionsController < ApplicationController
     redirect_to active_sessions_path, notice: "Session revoked successfully."
   end
 
+  # WebAuthn authentication methods
+  def webauthn_challenge
+    email = params[:email]&.strip&.downcase
+
+    if email.blank?
+      render json: { error: "Email is required" }, status: :unprocessable_entity
+      return
+    end
+
+    user = User.find_by(email_address: email)
+
+    if user.nil? || !user.can_authenticate_with_webauthn?
+      render json: { error: "User not found or WebAuthn not available" }, status: :unprocessable_entity
+      return
+    end
+
+    # Store user ID in session for verification
+    session[:pending_webauthn_user_id] = user.id
+
+    # Store redirect URL if present
+    if params[:rd].present?
+      validated_url = validate_redirect_url(params[:rd])
+      session[:webauthn_redirect_url] = validated_url if validated_url
+    end
+
+    begin
+      # Generate authentication options
+      # The WebAuthn gem will handle base64url encoding automatically
+      options = WebAuthn::Credential.options_for_get(
+        allow: user.webauthn_credentials.pluck(:external_id),
+        user_verification: "preferred"
+      )
+
+      # Store challenge in session
+      session[:webauthn_challenge] = options.challenge
+
+      render json: options
+
+    rescue => e
+      Rails.logger.error "WebAuthn challenge generation error: #{e.message}"
+      render json: { error: "Failed to generate WebAuthn challenge" }, status: :internal_server_error
+    end
+  end
+
+  def webauthn_verify
+    # Get pending user from session
+    user_id = session[:pending_webauthn_user_id]
+    unless user_id
+      render json: { error: "Session expired. Please try again." }, status: :unprocessable_entity
+      return
+    end
+
+    user = User.find_by(id: user_id)
+    unless user
+      session.delete(:pending_webauthn_user_id)
+      render json: { error: "Session expired. Please try again." }, status: :unprocessable_entity
+      return
+    end
+
+    # Get the credential and assertion from params
+    credential_data = params[:credential]
+    if credential_data.blank?
+      render json: { error: "Credential data is required" }, status: :unprocessable_entity
+      return
+    end
+
+    # Get the challenge from session
+    challenge = session.delete(:webauthn_challenge)
+
+    if challenge.blank?
+      render json: { error: "Invalid or expired session" }, status: :unprocessable_entity
+      return
+    end
+
+    begin
+      # Decode the credential response
+      webauthn_credential = WebAuthn::Credential.from_get(credential_data)
+
+      # Find the stored credential
+      external_id = Base64.urlsafe_encode64(webauthn_credential.id)
+      stored_credential = user.webauthn_credential_for(external_id)
+
+      if stored_credential.nil?
+        render json: { error: "Credential not found" }, status: :unprocessable_entity
+        return
+      end
+
+      # Verify the assertion
+      stored_public_key = Base64.urlsafe_decode64(stored_credential.public_key)
+      webauthn_credential.verify(
+        challenge,
+        public_key: stored_public_key,
+        sign_count: stored_credential.sign_count
+      )
+
+      # Check for suspicious sign count (possible clone)
+      if stored_credential.suspicious_sign_count?(webauthn_credential.sign_count)
+        Rails.logger.warn "Suspicious WebAuthn sign count for user #{user.id}, credential #{stored_credential.id}"
+        # You might want to notify admins or temporarily disable the credential
+      end
+
+      # Update credential usage
+      stored_credential.update_usage!(
+        sign_count: webauthn_credential.sign_count,
+        ip_address: request.remote_ip,
+        user_agent: request.user_agent
+      )
+
+      # Clean up session
+      session.delete(:pending_webauthn_user_id)
+      if session[:webauthn_redirect_url].present?
+        session[:return_to_after_authenticating] = session.delete(:webauthn_redirect_url)
+      end
+
+      # Create session
+      start_new_session_for user
+
+      render json: {
+        success: true,
+        redirect_to: after_authentication_url,
+        message: "Signed in successfully with passkey"
+      }
+
+    rescue WebAuthn::Error => e
+      Rails.logger.error "WebAuthn verification error: #{e.message}"
+      render json: { error: "Authentication failed: #{e.message}" }, status: :unprocessable_entity
+    rescue JSON::ParserError => e
+      Rails.logger.error "WebAuthn JSON parsing error: #{e.message}"
+      render json: { error: "Invalid credential format" }, status: :unprocessable_entity
+    rescue => e
+      Rails.logger.error "Unexpected WebAuthn verification error: #{e.class} - #{e.message}"
+      render json: { error: "An unexpected error occurred" }, status: :internal_server_error
+    end
+  end
+
   private
 
   def validate_redirect_url(url)

app/controllers/webauthn_controller.rb

@@ -0,0 +1,198 @@
+class WebauthnController < ApplicationController
+  before_action :set_webauthn_credential, only: [:destroy]
+  skip_before_action :require_authentication, only: [:check]
+
+  # GET /webauthn/new
+  def new
+    @webauthn_credential = WebauthnCredential.new
+  end
+
+  # POST /webauthn/challenge
+  # Generate registration challenge for creating a new passkey
+  def challenge
+    user = Current.session&.user
+    return render json: { error: "Not authenticated" }, status: :unauthorized unless user
+
+    registration_options = WebAuthn::Credential.options_for_create(
+      user: {
+        id: user.webauthn_user_handle,
+        name: user.email_address,
+        display_name: user.name || user.email_address
+      },
+      exclude: user.webauthn_credentials.pluck(:external_id),
+      authenticator_selection: {
+        userVerification: "preferred",
+        residentKey: "preferred",
+        authenticatorAttachment: "platform" # Prefer platform authenticators first
+      }
+    )
+
+    # Store challenge in session for verification
+    session[:webauthn_challenge] = registration_options.challenge
+
+    render json: registration_options
+  end
+
+  # POST /webauthn/create
+  # Verify and store the new credential
+  def create
+    credential_data, nickname = extract_credential_params
+
+    if credential_data.blank? || nickname.blank?
+      render json: { error: "Credential and nickname are required" }, status: :unprocessable_entity
+      return
+    end
+
+    # Retrieve the challenge from session
+    challenge = session.delete(:webauthn_challenge)
+
+    if challenge.blank?
+      render json: { error: "Invalid or expired session" }, status: :unprocessable_entity
+      return
+    end
+
+    begin
+      # Pass the credential hash directly to WebAuthn gem
+      webauthn_credential = WebAuthn::Credential.from_create(credential_data.to_h)
+
+      # Verify the credential against the challenge
+      webauthn_credential.verify(challenge)
+
+      # Extract credential metadata from the hash
+      response = credential_data.to_h
+      client_extension_results = response["clientExtensionResults"] || {}
+
+      authenticator_type = if response["response"]["authenticatorAttachment"] == "cross-platform"
+                            "cross-platform"
+                          else
+                            "platform"
+                          end
+
+      # Determine if this is a backup/synced credential
+      backup_eligible = client_extension_results["credProps"]&.dig("rk") || false
+      backup_state = client_extension_results["credProps"]&.dig("backup") || false
+
+      # Store the credential
+      user = Current.session&.user
+      return render json: { error: "Not authenticated" }, status: :unauthorized unless user
+
+      @webauthn_credential = user.webauthn_credentials.create!(
+        external_id: Base64.urlsafe_encode64(webauthn_credential.id),
+        public_key: Base64.urlsafe_encode64(webauthn_credential.public_key),
+        sign_count: webauthn_credential.sign_count,
+        nickname: nickname,
+        authenticator_type: authenticator_type,
+        backup_eligible: backup_eligible,
+        backup_state: backup_state
+      )
+
+      render json: {
+        success: true,
+        message: "Passkey '#{nickname}' registered successfully",
+        credential_id: @webauthn_credential.id
+      }
+
+    rescue WebAuthn::Error => e
+      Rails.logger.error "WebAuthn registration error: #{e.message}"
+      render json: { error: "Failed to register passkey: #{e.message}" }, status: :unprocessable_entity
+    rescue => e
+      Rails.logger.error "Unexpected WebAuthn registration error: #{e.class} - #{e.message}"
+      render json: { error: "An unexpected error occurred" }, status: :internal_server_error
+    end
+  end
+
+  # DELETE /webauthn/:id
+  # Remove a passkey
+  def destroy
+    user = Current.session&.user
+    return render json: { error: "Not authenticated" }, status: :unauthorized unless user
+
+    if @webauthn_credential.user != user
+      render json: { error: "Unauthorized" }, status: :forbidden
+      return
+    end
+
+    nickname = @webauthn_credential.nickname
+    @webauthn_credential.destroy
+
+    respond_to do |format|
+      format.html {
+        redirect_to profile_path,
+        notice: "Passkey '#{nickname}' has been removed"
+      }
+      format.json {
+        render json: {
+          success: true,
+          message: "Passkey '#{nickname}' has been removed"
+        }
+      }
+    end
+  end
+
+  # GET /webauthn/check
+  # Check if user has WebAuthn credentials (for login page detection)
+  def check
+    email = params[:email]&.strip&.downcase
+
+    if email.blank?
+      render json: { has_webauthn: false, error: "Email is required" }
+      return
+    end
+
+    user = User.find_by(email_address: email)
+
+    if user.nil?
+      render json: { has_webauthn: false, message: "User not found" }
+      return
+    end
+
+    render json: {
+      has_webauthn: user.can_authenticate_with_webauthn?,
+      user_id: user.id,
+      preferred_method: user.preferred_authentication_method,
+      requires_webauthn: user.require_webauthn?
+    }
+  end
+
+  private
+
+  def extract_credential_params
+    # Use require.permit which is working and reliable
+    # The JavaScript sends params both directly and wrapped in webauthn key
+    begin
+      # Try direct parameters first
+      credential_params = params.require(:credential).permit(:id, :rawId, :type, response: {}, clientExtensionResults: {})
+      nickname = params.require(:nickname)
+      [credential_params, nickname]
+    rescue ActionController::ParameterMissing
+      Rails.logger.error("Using the fallback parameters")
+      # Fallback to webauthn-wrapped parameters
+      webauthn_params = params.require(:webauthn).permit(:nickname, credential: [:id, :rawId, :type, response: {}, clientExtensionResults: {}])
+      [webauthn_params[:credential], webauthn_params[:nickname]]
+    end
+  end
+
+  def set_webauthn_credential
+    @webauthn_credential = WebauthnCredential.find(params[:id])
+  rescue ActiveRecord::RecordNotFound
+    respond_to do |format|
+      format.html {
+        redirect_to profile_path,
+        alert: "Passkey not found"
+      }
+      format.json {
+        render json: { error: "Passkey not found" }, status: :not_found
+      }
+    end
+  end
+
+  # Helper method to convert Base64 to Base64URL if needed
+  def base64_to_base64url(str)
+    str.gsub('+', '-').gsub('/', '_').gsub(/=+$/, '')
+  end
+
+  # Helper method to convert Base64URL to Base64 if needed
+  def base64url_to_base64(str)
+    str.gsub('-', '+').gsub('_', '/') + '=' * (4 - str.length % 4) % 4
+  end
+end

app/javascript/controllers/webauthn_controller.js

@@ -0,0 +1,317 @@
+import { Controller } from "@hotwired/stimulus";
+
+export default class extends Controller {
+  static targets = ["nickname", "submitButton", "status", "error"];
+  static values = {
+    challengeUrl: String,
+    createUrl: String,
+    checkUrl: String
+  };
+
+  connect() {
+    // Check if WebAuthn is supported
+    if (!this.isWebAuthnSupported()) {
+      console.warn("WebAuthn is not supported in this browser");
+      return;
+    }
+  }
+
+  // Check if browser supports WebAuthn
+  isWebAuthnSupported() {
+    return (
+      window.PublicKeyCredential !== undefined &&
+      typeof window.PublicKeyCredential === "function"
+    );
+  }
+
+  // Check if user has passkeys (for login page)
+  async checkWebAuthnSupport(event) {
+    const email = event.target.value.trim();
+
+    if (!email || !this.isValidEmail(email)) {
+      return;
+    }
+
+    try {
+      const response = await fetch(`${this.checkUrlValue}?email=${encodeURIComponent(email)}`);
+      const data = await response.json();
+
+      console.debug("WebAuthn check response:", data);
+
+      if (data.has_webauthn) {
+        console.debug("Dispatching webauthn-available event");
+        // Trigger custom event for login form to show passkey option
+        this.dispatch("webauthn-available", {
+          detail: {
+            hasWebauthn: data.has_webauthn,
+            requiresWebauthn: data.requires_webauthn,
+            preferredMethod: data.preferred_method
+          }
+        });
+
+        // Auto-trigger passkey authentication if required
+        if (data.requires_webauthn) {
+          setTimeout(() => this.authenticate(), 100);
+        }
+      } else {
+        console.debug("No WebAuthn credentials found for this email");
+      }
+    } catch (error) {
+      console.error("Error checking WebAuthn support:", error);
+    }
+  }
+
+  // Start registration ceremony
+  async register(event) {
+    event.preventDefault();
+
+    if (!this.isWebAuthnSupported()) {
+      this.showError("WebAuthn is not supported in your browser");
+      return;
+    }
+
+    const nickname = this.nicknameTarget.value.trim();
+    if (!nickname) {
+      this.showError("Please enter a nickname for this passkey");
+      return;
+    }
+
+    this.setLoading(true);
+    this.clearMessages();
+
+    try {
+      // Get registration challenge from server
+      const challengeResponse = await fetch(this.challengeUrlValue, {
+        method: "POST",
+        headers: {
+          "Content-Type": "application/json",
+          "X-CSRF-Token": this.getCSRFToken()
+        }
+      });
+
+      if (!challengeResponse.ok) {
+        throw new Error("Failed to get registration challenge");
+      }
+
+      const credentialCreationOptions = await challengeResponse.json();
+
+      // Use modern Web Authentication API Level 3 to parse options
+      // This automatically handles all base64url encoding/decoding
+      const publicKeyOptions = PublicKeyCredential.parseCreationOptionsFromJSON(
+        credentialCreationOptions
+      );
+
+      // Create credential via WebAuthn API
+      const credential = await navigator.credentials.create({
+        publicKey: publicKeyOptions
+      });
+
+      if (!credential) {
+        throw new Error("Failed to create credential");
+      }
+
+      // Send credential to server for verification
+      // Use toJSON() to properly serialize the credential
+      const credentialResponse = await fetch(this.createUrlValue, {
+        method: "POST",
+        headers: {
+          "Content-Type": "application/json",
+          "X-CSRF-Token": this.getCSRFToken()
+        },
+        body: JSON.stringify({
+          credential: credential.toJSON(),
+          nickname: nickname
+        })
+      });
+
+      const result = await credentialResponse.json();
+
+      if (result.success) {
+        this.showSuccess(result.message);
+
+        // Clear the form
+        this.nicknameTarget.value = "";
+
+        // Dispatch event to refresh the passkey list
+        this.dispatch("passkey-registered", {
+          detail: {
+            nickname: nickname,
+            credentialId: result.credential_id
+          }
+        });
+
+        // Optionally close modal or redirect
+        setTimeout(() => {
+          if (window.location.pathname === "/webauthn/new") {
+            window.location.href = "/profile";
+          }
+        }, 1500);
+      } else {
+        this.showError(result.error || "Failed to register passkey");
+      }
+
+    } catch (error) {
+      console.error("WebAuthn registration error:", error);
+      this.showError(this.getErrorMessage(error));
+    } finally {
+      this.setLoading(false);
+    }
+  }
+
+  // Start authentication ceremony
+  async authenticate(event) {
+    if (event) {
+      event.preventDefault();
+    }
+
+    if (!this.isWebAuthnSupported()) {
+      this.showError("WebAuthn is not supported in your browser");
+      return;
+    }
+
+    this.setLoading(true);
+    this.clearMessages();
+
+    try {
+      // Get authentication challenge from server
+      const response = await fetch("/sessions/webauthn/challenge", {
+        method: "POST",
+        headers: {
+          "Content-Type": "application/json",
+          "X-CSRF-Token": this.getCSRFToken()
+        },
+        body: JSON.stringify({
+          email: this.getUserEmail()
+        })
+      });
+
+      if (!response.ok) {
+        throw new Error("Failed to get authentication challenge");
+      }
+
+      const credentialRequestOptions = await response.json();
+
+      // Use modern Web Authentication API Level 3 to parse options
+      // This automatically handles all base64url encoding/decoding
+      const publicKeyOptions = PublicKeyCredential.parseRequestOptionsFromJSON(
+        credentialRequestOptions
+      );
+
+      // Get credential via WebAuthn API
+      const credential = await navigator.credentials.get({
+        publicKey: publicKeyOptions
+      });
+
+      if (!credential) {
+        throw new Error("Failed to get credential");
+      }
+
+      // Send assertion to server for verification
+      // Use toJSON() to properly serialize the credential
+      const authResponse = await fetch("/sessions/webauthn/verify", {
+        method: "POST",
+        headers: {
+          "Content-Type": "application/json",
+          "X-CSRF-Token": this.getCSRFToken()
+        },
+        body: JSON.stringify({
+          credential: credential.toJSON(),
+          email: this.getUserEmail()
+        })
+      });
+
+      const result = await authResponse.json();
+
+      if (result.success) {
+        // Redirect to dashboard or intended URL
+        window.location.href = result.redirect_to || "/";
+      } else {
+        this.showError(result.error || "Authentication failed");
+      }
+
+    } catch (error) {
+      console.error("WebAuthn authentication error:", error);
+      this.showError(this.getErrorMessage(error));
+    } finally {
+      this.setLoading(false);
+    }
+  }
+
+  // UI helper methods
+  setLoading(isLoading) {
+    if (this.hasSubmitButtonTarget) {
+      this.submitButtonTarget.disabled = isLoading;
+      this.submitButtonTarget.textContent = isLoading ? "Registering..." : "Register Passkey";
+    }
+  }
+
+  showSuccess(message) {
+    if (this.hasStatusTarget) {
+      this.statusTarget.textContent = message;
+      this.statusTarget.className = "mt-2 text-sm text-green-600";
+      this.statusTarget.style.display = "block";
+    }
+  }
+
+  showError(message) {
+    if (this.hasErrorTarget) {
+      this.errorTarget.textContent = message;
+      this.errorTarget.className = "mt-2 text-sm text-red-600";
+      this.errorTarget.style.display = "block";
+    }
+  }
+
+  clearMessages() {
+    if (this.hasStatusTarget) {
+      this.statusTarget.style.display = "none";
+      this.statusTarget.textContent = "";
+    }
+    if (this.hasErrorTarget) {
+      this.errorTarget.style.display = "none";
+      this.errorTarget.textContent = "";
+    }
+  }
+
+  getCSRFToken() {
+    const meta = document.querySelector('meta[name="csrf-token"]');
+    return meta ? meta.getAttribute("content") : "";
+  }
+
+  getUserEmail() {
+    // Try multiple ways to get the user email from login form
+    let emailInput = document.querySelector('input[type="email"]');
+    if (!emailInput) {
+      emailInput = document.querySelector('input[name="email"]');
+    }
+    if (!emailInput) {
+      emailInput = document.querySelector('input[name="session[email_address]"]');
+    }
+    if (!emailInput) {
+      emailInput = document.querySelector('input[name="user[email_address]"]');
+    }
+    return emailInput ? emailInput.value.trim() : "";
+  }
+
+  isValidEmail(email) {
+    return /^[^\s@]+@[^\s@]+\.[^\s@]+$/.test(email);
+  }
+
+  getErrorMessage(error) {
+    // Common WebAuthn errors
+    if (error.name === "NotAllowedError") {
+      return "Authentication was cancelled or timed out. Please try again.";
+    }
+    if (error.name === "SecurityError") {
+      return "Security requirements not met. Make sure you're using HTTPS.";
+    }
+    if (error.name === "NotSupportedError") {
+      return "This device doesn't support the requested authentication method.";
+    }
+    if (error.name === "InvalidStateError") {
+      return "This authenticator has already been registered.";
+    }
+
+    // Fallback to error message
+    return error.message || "An unexpected error occurred";
+  }
+}

app/models/user.rb

@@ -4,6 +4,7 @@ class User < ApplicationRecord
   has_many :user_groups, dependent: :destroy
   has_many :groups, through: :user_groups
   has_many :oidc_user_consents, dependent: :destroy
+  has_many :webauthn_credentials, dependent: :destroy
 
   # Token generation for passwordless flows
   generates_token_for :invitation_login, expires_in: 24.hours do
@@ -80,6 +81,54 @@ class User < ApplicationRecord
     JSON.parse(backup_codes)
   end
 
+  # WebAuthn methods
+  def webauthn_enabled?
+    webauthn_credentials.exists?
+  end
+
+  def can_authenticate_with_webauthn?
+    webauthn_enabled? && active?
+  end
+
+  def require_webauthn?
+    webauthn_required? || (webauthn_enabled? && !password_digest.present?)
+  end
+
+  # Generate stable WebAuthn user handle on first use
+  def webauthn_user_handle
+    return webauthn_id if webauthn_id.present?
+
+    # Generate random 64-byte opaque identifier (base64url encoded)
+    handle = SecureRandom.urlsafe_base64(64)
+    update_column(:webauthn_id, handle)
+    handle
+  end
+
+  def platform_authenticators
+    webauthn_credentials.platform_authenticators
+  end
+
+  def roaming_authenticators
+    webauthn_credentials.roaming_authenticators
+  end
+
+  def webauthn_credential_for(external_id)
+    webauthn_credentials.find_by(external_id: external_id)
+  end
+
+  # Check if user has any backed up (synced) passkeys
+  def has_synced_passkeys?
+    webauthn_credentials.exists?(backup_eligible: true, backup_state: true)
+  end
+
+  # Preferred authentication method for login flow
+  def preferred_authentication_method
+    return :webauthn if require_webauthn?
+    return :webauthn if can_authenticate_with_webauthn? && preferred_2fa_method == "webauthn"
+    return :password if password_digest.present?
+    :webauthn
+  end
+
   def has_oidc_consent?(application, requested_scopes)
     oidc_user_consents
       .where(application: application)

app/models/webauthn_credential.rb

@@ -0,0 +1,96 @@
+class WebauthnCredential < ApplicationRecord
+  belongs_to :user
+
+  # Validations
+  validates :external_id, presence: true, uniqueness: true
+  validates :public_key, presence: true
+  validates :sign_count, presence: true, numericality: { greater_than_or_equal_to: 0, only_integer: true }
+  validates :nickname, presence: true
+  validates :authenticator_type, inclusion: { in: %w[platform cross-platform] }
+
+  # Scopes for querying
+  scope :active, -> { where(nil) } # All credentials are active (we can add revoked_at later if needed)
+  scope :platform_authenticators, -> { where(authenticator_type: "platform") }
+  scope :roaming_authenticators, -> { where(authenticator_type: "cross-platform") }
+  scope :recently_used, -> { where.not(last_used_at: nil).order(last_used_at: :desc) }
+  scope :never_used, -> { where(last_used_at: nil) }
+
+  # Update last used timestamp and sign count after successful authentication
+  def update_usage!(sign_count:, ip_address: nil, user_agent: nil)
+    update!(
+      last_used_at: Time.current,
+      last_used_ip: ip_address,
+      sign_count: sign_count,
+      user_agent: user_agent
+    )
+  end
+
+  # Check if this is a platform authenticator (built-in device)
+  def platform_authenticator?
+    authenticator_type == "platform"
+  end
+
+  # Check if this is a roaming authenticator (USB/NFC/Bluetooth key)
+  def roaming_authenticator?
+    authenticator_type == "cross-platform"
+  end
+
+  # Check if this credential is backed up (synced passkeys)
+  def backed_up?
+    backup_eligible? && backup_state?
+  end
+
+  # Human readable description
+  def description
+    if nickname.present?
+      "#{nickname} (#{authenticator_type.humanize})"
+    else
+      "#{authenticator_type.humanize} Authenticator"
+    end
+  end
+
+  # Check if sign count is suspicious (clone detection)
+  def suspicious_sign_count?(new_sign_count)
+    return false if sign_count.zero? && new_sign_count > 0 # First use
+    return false if new_sign_count > sign_count # Normal increment
+
+    # Sign count didn't increase - possible clone
+    true
+  end
+
+  # Format for display in UI
+  def display_name
+    nickname || "#{authenticator_type&.humanize} Authenticator"
+  end
+
+  # When was this credential created?
+  def created_recently?
+    created_at > 1.week.ago
+  end
+
+  # How long ago was this last used?
+  def last_used_ago
+    return "Never" unless last_used_at
+
+    time_ago_in_words(last_used_at)
+  end
+
+  private
+
+  def time_ago_in_words(time)
+    seconds = Time.current - time
+    minutes = seconds / 60
+    hours = minutes / 60
+    days = hours / 24
+
+    if days > 0
+      "#{days.floor} day#{'s' if days > 1} ago"
+    elsif hours > 0
+      "#{hours.floor} hour#{'s' if hours > 1} ago"
+    elsif minutes > 0
+      "#{minutes.floor} minute#{'s' if minutes > 1} ago"
+    else
+      "Just now"
+    end
+  end
+end

app/views/profiles/show.html.erb

@@ -181,6 +181,128 @@
     </div>
   </div>
 
+  <!-- Passkeys (WebAuthn) -->
+  <div class="bg-white shadow sm:rounded-lg">
+    <div class="px-4 py-5 sm:p-6" data-controller="webauthn" data-webauthn-challenge-url-value="/webauthn/challenge" data-webauthn-create-url-value="/webauthn/create">
+      <h3 class="text-lg font-medium leading-6 text-gray-900">Passkeys</h3>
+      <div class="mt-2 max-w-xl text-sm text-gray-500">
+        <p>Use your fingerprint, face recognition, or security key to sign in without passwords.</p>
+      </div>
+
+      <!-- Add Passkey Form -->
+      <div class="mt-5">
+        <div id="add-passkey-form" class="space-y-4">
+          <div>
+            <label for="passkey-nickname" class="block text-sm font-medium text-gray-700">Passkey Name</label>
+            <input type="text"
+                   id="passkey-nickname"
+                   data-webauthn-target="nickname"
+                   placeholder="e.g., MacBook Touch ID, iPhone Face ID"
+                   class="mt-1 block w-full rounded-md border-gray-300 shadow-sm focus:border-blue-500 focus:ring-blue-500 sm:text-sm">
+            <p class="mt-1 text-sm text-gray-500">Give this passkey a memorable name so you can identify it later.</p>
+          </div>
+
+          <div>
+            <button type="button"
+                    data-action="click->webauthn#register"
+                    data-webauthn-target="submitButton"
+                    class="inline-flex items-center rounded-md border border-transparent bg-green-600 px-4 py-2 text-sm font-medium text-white shadow-sm hover:bg-green-700 focus:outline-none focus:ring-2 focus:ring-green-500 focus:ring-offset-2">
+              <svg class="w-4 h-4 mr-2" fill="none" stroke="currentColor" viewBox="0 0 24 24">
+                <path stroke-linecap="round" stroke-linejoin="round" stroke-width="2" d="M12 4v16m8-8H4"></path>
+              </svg>
+              Add New Passkey
+            </button>
+          </div>
+
+          <!-- Status Messages -->
+          <div data-webauthn-target="status" class="hidden mt-2 p-3 rounded-md text-sm"></div>
+          <div data-webauthn-target="error" class="hidden mt-2 p-3 rounded-md text-sm"></div>
+        </div>
+      </div>
+
+      <!-- Existing Passkeys List -->
+      <div class="mt-8">
+        <h4 class="text-md font-medium text-gray-900 mb-4">Your Passkeys</h4>
+        <% if @user.webauthn_credentials.exists? %>
+          <div class="space-y-3">
+            <% @user.webauthn_credentials.order(created_at: :desc).each do |credential| %>
+              <div class="flex items-center justify-between p-4 bg-gray-50 rounded-lg">
+                <div class="flex items-center space-x-3">
+                  <div class="flex-shrink-0">
+                    <% if credential.platform_authenticator? %>
+                      <!-- Platform authenticator icon -->
+                      <svg class="w-6 h-6 text-blue-500" fill="none" stroke="currentColor" viewBox="0 0 24 24">
+                        <path stroke-linecap="round" stroke-linejoin="round" stroke-width="2" d="M9.75 17L9 20l-1 1h8l-1-1-.75-3M3 13h18M5 17h14a2 2 0 002-2V5a2 2 0 00-2-2H5a2 2 0 00-2 2v10a2 2 0 002 2z"></path>
+                      </svg>
+                    <% else %>
+                      <!-- Roaming authenticator icon -->
+                      <svg class="w-6 h-6 text-green-500" fill="none" stroke="currentColor" viewBox="0 0 24 24">
+                        <path stroke-linecap="round" stroke-linejoin="round" stroke-width="2" d="M15 7a2 2 0 012 2m4 0a6 6 0 01-7.743 5.743L11 17H9v2H7v2H4a1 1 0 01-1-1v-2.586a1 1 0 01.293-.707l5.964-5.964A6 6 0 1121 9z"></path>
+                      </svg>
+                    <% end %>
+                  </div>
+                  <div>
+                    <div class="text-sm font-medium text-gray-900">
+                      <%= credential.nickname %>
+                    </div>
+                    <div class="text-sm text-gray-500">
+                      <%= credential.authenticator_type.humanize %> •
+                      Last used <%= credential.last_used_ago %>
+                      <% if credential.backed_up? %>
+                        • <span class="text-green-600">Synced</span>
+                      <% end %>
+                    </div>
+                  </div>
+                </div>
+                <div class="flex items-center space-x-2">
+                  <% if credential.created_recently? %>
+                    <span class="inline-flex items-center px-2.5 py-0.5 rounded-full text-xs font-medium bg-green-100 text-green-800">
+                      New
+                    </span>
+                  <% end %>
+                  <%= link_to webauthn_credential_path(credential),
+                              method: :delete,
+                              data: {
+                                confirm: "Are you sure you want to delete '#{credential.nickname}'? You'll need to set it up again to sign in with this device.",
+                                turbo_method: :delete
+                              },
+                              class: "text-red-600 hover:text-red-800 text-sm font-medium" do %>
+                    <svg class="w-4 h-4" fill="none" stroke="currentColor" viewBox="0 0 24 24">
+                      <path stroke-linecap="round" stroke-linejoin="round" stroke-width="2" d="M19 7l-.867 12.142A2 2 0 0116.138 21H7.862a2 2 0 01-1.995-1.858L5 7m5 4v6m4-6v6m1-10V4a1 1 0 00-1-1h-4a1 1 0 00-1 1v3M4 7h16"></path>
+                    </svg>
+                  <% end %>
+                </div>
+              </div>
+            <% end %>
+          </div>
+
+          <div class="mt-4 p-3 bg-blue-50 rounded-lg">
+            <div class="flex">
+              <div class="flex-shrink-0">
+                <svg class="h-5 w-5 text-blue-400" viewBox="0 0 20 20" fill="currentColor">
+                  <path fill-rule="evenodd" d="M18 10a8 8 0 11-16 0 8 8 0 0116 0zm-7-4a1 1 0 11-2 0 1 1 0 012 0zM9 9a1 1 0 000 2v3a1 1 0 001 1h1a1 1 0 100-2v-3a1 1 0 00-1-1H9z" clip-rule="evenodd" />
+                </svg>
+              </div>
+              <div class="ml-3">
+                <p class="text-sm text-blue-800">
+                  <strong>Tip:</strong> Add passkeys on multiple devices for easy access. Platform authenticators (like Touch ID) are synced across your devices if you use iCloud Keychain or Google Password Manager.
+                </p>
+              </div>
+            </div>
+          </div>
+        <% else %>
+          <div class="text-center py-8">
+            <svg class="mx-auto h-12 w-12 text-gray-400" fill="none" stroke="currentColor" viewBox="0 0 24 24">
+              <path stroke-linecap="round" stroke-linejoin="round" stroke-width="2" d="M15 7a2 2 0 012 2m4 0a6 6 0 01-7.743 5.743L11 17H9v2H7v2H4a1 1 0 01-1-1v-2.586a1 1 0 01.293-.707l5.964-5.964A6 6 0 1121 9z"></path>
+            </svg>
+            <h3 class="mt-2 text-sm font-medium text-gray-900">No passkeys</h3>
+            <p class="mt-1 text-sm text-gray-500">Get started by adding your first passkey for passwordless sign-in.</p>
+          </div>
+        <% end %>
+      </div>
+    </div>
+  </div>
+
   <script>
     function showDisable2FAModal() {
       document.getElementById('disable-2fa-modal').classList.remove('hidden');

app/views/sessions/new.html.erb

@@ -1,4 +1,4 @@
-<div class="mx-auto md:w-2/3 w-full">
+<div class="mx-auto md:w-2/3 w-full" data-controller="webauthn" data-webauthn-check-url-value="/webauthn/check">
   <div class="mb-8">
     <h1 class="font-bold text-4xl">Sign in to Clinch</h1>
   </div>
@@ -13,26 +13,138 @@
           autocomplete: "username",
           placeholder: "your@email.com",
           value: params[:email_address],
+          data: { action: "blur->webauthn#checkWebAuthnSupport change->webauthn#checkWebAuthnSupport" },
           class: "block shadow-sm rounded-md border border-gray-400 focus:outline-blue-600 px-3 py-2 mt-2 w-full" %>
     </div>
 
-    <div class="my-5">
+    <!-- WebAuthn section - initially hidden -->
-      <%= form.label :password, class: "block font-medium text-sm text-gray-700" %>
+    <div id="webauthn-section" class="my-5 hidden">
-      <%= form.password_field :password,
+      <div class="bg-green-50 border border-green-200 rounded-lg p-4 mb-4">
-          required: true,
+        <div class="flex items-center">
-          autocomplete: "current-password",
+          <svg class="w-5 h-5 text-green-600 mr-2" fill="none" stroke="currentColor" viewBox="0 0 24 24">
-          placeholder: "Enter your password",
+            <path stroke-linecap="round" stroke-linejoin="round" stroke-width="2" d="M9 12l2 2 4-4m6 2a9 9 0 11-18 0 9 9 0 0118 0z"></path>
-          maxlength: 72,
+          </svg>
-          class: "block shadow-sm rounded-md border border-gray-400 focus:outline-blue-600 px-3 py-2 mt-2 w-full" %>
+          <p class="text-sm text-green-800">
+            <strong>Passkey detected!</strong> You can sign in without a password.
+          </p>
+        </div>
+      </div>
+
+      <button type="button"
+              data-action="click->webauthn#authenticate"
+              class="w-full rounded-md px-3.5 py-2.5 bg-green-600 hover:bg-green-500 text-white font-medium cursor-pointer flex items-center justify-center">
+        <svg class="w-5 h-5 mr-2" fill="none" stroke="currentColor" viewBox="0 0 24 24">
+          <path stroke-linecap="round" stroke-linejoin="round" stroke-width="2" d="M15 7a2 2 0 012 2m4 0a6 6 0 01-7.743 5.743L11 17H9v2H7v2H4a1 1 0 01-1-1v-2.586a1 1 0 01.293-.707l5.964-5.964A6 6 0 1121 9z"></path>
+        </svg>
+        Continue with Passkey
+      </button>
     </div>
 
-    <div class="my-5">
+    <!-- Password section - shown by default, hidden if WebAuthn is required -->
-      <%= form.submit "Sign in",
+    <div id="password-section">
-          class: "w-full rounded-md px-3.5 py-2.5 bg-blue-600 hover:bg-blue-500 text-white font-medium cursor-pointer" %>
+      <div class="my-5">
+        <%= form.label :password, class: "block font-medium text-sm text-gray-700" %>
+        <%= form.password_field :password,
+            required: true,
+            autocomplete: "current-password",
+            placeholder: "Enter your password",
+            maxlength: 72,
+            class: "block shadow-sm rounded-md border border-gray-400 focus:outline-blue-600 px-3 py-2 mt-2 w-full" %>
+      </div>
+
+      <div class="my-5">
+        <%= form.submit "Sign in",
+            class: "w-full rounded-md px-3.5 py-2.5 bg-blue-600 hover:bg-blue-500 text-white font-medium cursor-pointer" %>
+      </div>
     </div>
 
     <div class="mt-4 text-sm text-gray-600 text-center">
       <%= link_to "Forgot your password?", new_password_path, class: "text-blue-600 hover:text-blue-500 underline" %>
     </div>
   <% end %>
+
+  <!-- Loading overlay -->
+  <div id="loading-overlay" class="hidden fixed inset-0 bg-gray-600 bg-opacity-50 flex items-center justify-center z-50">
+    <div class="bg-white rounded-lg p-6 flex items-center">
+      <svg class="animate-spin -ml-1 mr-3 h-5 w-5 text-blue-600" fill="none" viewBox="0 0 24 24">
+        <circle class="opacity-25" cx="12" cy="12" r="10" stroke="currentColor" stroke-width="4"></circle>
+        <path class="opacity-75" fill="currentColor" d="M4 12a8 8 0 018-8V0C5.373 0 0 5.373 0 12h4zm2 5.291A7.962 7.962 0 014 12H0c0 3.042 1.135 5.824 3 7.938l3-2.647z"></path>
+      </svg>
+      <span>Authenticating...</span>
+    </div>
+  </div>
+
+  <!-- Status messages -->
+  <div id="status-message" class="hidden mt-4 p-3 rounded-md"></div>
 </div>
+
+<script>
+document.addEventListener('DOMContentLoaded', function() {
+  const webauthnController = document.querySelector('[data-controller="webauthn"]');
+
+  if (webauthnController) {
+    // Listen for WebAuthn availability events
+    webauthnController.addEventListener('webauthn:webauthn-available', function(event) {
+      console.debug("Received webauthn-available event:", event.detail);
+      const detail = event.detail;
+      const webauthnSection = document.getElementById('webauthn-section');
+      const passwordSection = document.getElementById('password-section');
+
+      if (detail.hasWebauthn) {
+        console.debug("Showing WebAuthn section");
+        webauthnSection.classList.remove('hidden');
+
+        // If WebAuthn is required, hide password section
+        if (detail.requiresWebauthn) {
+          passwordSection.classList.add('hidden');
+        } else {
+          // Show both options
+          passwordSection.classList.add('border-t pt-4 mt-4');
+
+          // Add an "or" divider
+          const orDiv = document.createElement('div');
+          orDiv.className = 'relative my-4';
+          orDiv.innerHTML = `
+            <div class="absolute inset-0 flex items-center">
+              <div class="w-full border-t border-gray-300"></div>
+            </div>
+            <div class="relative flex justify-center text-sm">
+              <span class="px-2 bg-white text-gray-500">Or</span>
+            </div>
+          `;
+          webauthnSection.parentNode.insertBefore(orDiv, webauthnSection);
+        }
+      } else {
+        console.debug("WebAuthn not available, keeping section hidden");
+      }
+    });
+
+    // Listen for WebAuthn registration events (from profile page)
+    webauthnController.addEventListener('webauthn:passkey-registered', function(event) {
+      // Show success message
+      const statusMessage = document.getElementById('status-message');
+      statusMessage.className = 'mt-4 p-3 rounded-md bg-green-50 text-green-800 border border-green-200';
+      statusMessage.textContent = 'Passkey registered successfully!';
+      statusMessage.classList.remove('hidden');
+
+      // Hide after 3 seconds
+      setTimeout(() => {
+        statusMessage.classList.add('hidden');
+      }, 3000);
+    });
+  }
+
+  // Loading overlay management
+  function showLoading() {
+    document.getElementById('loading-overlay').classList.remove('hidden');
+  }
+
+  function hideLoading() {
+    document.getElementById('loading-overlay').classList.add('hidden');
+  }
+
+  // Show loading when WebAuthn authentication starts
+  document.addEventListener('webauthn:authenticate-start', showLoading);
+  document.addEventListener('webauthn:authenticate-end', hideLoading);
+});
+</script>

config/initializers/webauthn.rb

@@ -0,0 +1,54 @@
+# WebAuthn configuration for Clinch Identity Provider
+WebAuthn.configure do |config|
+  # Relying Party name (displayed in authenticator prompts)
+  # For development, use http://localhost to match passkey in Passwords app
+  origin_host = ENV.fetch("CLINCH_HOST", "http://localhost")
+  config.allowed_origins = [origin_host]
+
+  # Relying Party ID (must match origin domain)
+  # Extract domain from origin for RP ID
+  origin_uri = URI.parse(origin_host)
+  config.rp_id = ENV.fetch("CLINCH_RP_ID", "localhost")
+
+  # For development, we also allow localhost with common ports and without port
+  if Rails.env.development?
+    config.allowed_origins += [
+      "http://localhost",
+      "http://localhost:3000",
+      "http://localhost:3035",
+      "http://127.0.0.1",
+      "http://127.0.0.1:3000",
+      "http://127.0.0.1:3035"
+    ]
+  end
+
+  # Relying Party name shown in authenticator prompts
+  config.rp_name = ENV.fetch("CLINCH_RP_NAME", "Clinch Identity Provider")
+
+  # Credential timeout in milliseconds (60 seconds)
+  # Users have 60 seconds to complete the authentication ceremony
+  config.credential_options_timeout = 60_000
+
+  # Supported algorithms for credential creation
+  # ES256: ECDSA with P-256 and SHA-256 (most common, secure)
+  # RS256: RSASSA-PKCS1-v1_5 with SHA-256 (hardware keys often use this)
+  config.algorithms = ["ES256", "RS256"]
+
+  # Encoding for credential IDs and other data
+  config.encoding = :base64url
+
+  # Custom verifier for additional security checks if needed
+  # config.verifier = MyCustomVerifier.new
+end
+
+# Security note: WebAuthn requires HTTPS in production
+# The WebAuthn API will not work on non-secure origins in production browsers
+# Ensure CLINCH_HOST uses https:// in production environments
+
+# Example environment variables:
+# CLINCH_HOST=https://auth.example.com
+# CLINCH_RP_ID=example.com
+# CLINCH_RP_NAME="Example Company Identity Provider"
+# CLINCH_WEBAUTHN_ATTESTATION=none
+# CLINCH_WEBAUTHN_USER_VERIFICATION=preferred
+# CLINCH_WEBAUTHN_RESIDENT_KEY=preferred

config/routes.rb

@@ -19,6 +19,10 @@ Rails.application.routes.draw do
   get "/totp-verification", to: "sessions#verify_totp", as: :totp_verification
   post "/totp-verification", to: "sessions#verify_totp"
 
+  # WebAuthn authentication routes
+  post "/sessions/webauthn/challenge", to: "sessions#webauthn_challenge"
+  post "/sessions/webauthn/verify", to: "sessions#webauthn_verify"
+
   # OIDC (OpenID Connect) routes
   get "/.well-known/openid-configuration", to: "oidc#discovery"
   get "/.well-known/jwks.json", to: "oidc#jwks"
@@ -61,6 +65,13 @@ Rails.application.routes.draw do
   get '/totp/backup_codes', to: 'totp#backup_codes', as: :backup_codes_totp
   post '/totp/verify_password', to: 'totp#verify_password', as: :verify_password_totp
 
+  # WebAuthn (Passkeys) routes
+  get '/webauthn/new', to: 'webauthn#new', as: :new_webauthn
+  post '/webauthn/challenge', to: 'webauthn#challenge'
+  post '/webauthn/create', to: 'webauthn#create'
+  delete '/webauthn/:id', to: 'webauthn#destroy', as: :webauthn_credential
+  get '/webauthn/check', to: 'webauthn#check'
+
   # Admin routes
   namespace :admin do
     root "dashboard#index"

db/migrate/20251104042155_create_webauthn_credentials.rb

@@ -0,0 +1,32 @@
+class CreateWebauthnCredentials < ActiveRecord::Migration[8.1]
+  def change
+    create_table :webauthn_credentials do |t|
+      # Reference to the user who owns this credential
+      t.references :user, null: false, foreign_key: true, index: true
+
+      # WebAuthn specification fields
+      t.string :external_id, null: false, index: { unique: true }  # credential ID (base64)
+      t.string :public_key, null: false                             # public key (base64)
+      t.integer :sign_count, null: false, default: 0                # signature counter (clone detection)
+
+      # Metadata
+      t.string :nickname                                            # User-friendly name ("MacBook Touch ID")
+      t.string :authenticator_type                                  # "platform" or "cross-platform"
+      t.boolean :backup_eligible, default: false                    # Can be backed up (passkey sync)
+      t.boolean :backup_state, default: false                       # Currently backed up
+
+      # Tracking
+      t.datetime :last_used_at
+      t.string :last_used_ip
+      t.string :user_agent                                          # Browser/OS info
+
+      t.timestamps
+    end
+
+    # Add composite index for user-specific queries
+    add_index :webauthn_credentials, [:user_id, :external_id], unique: true
+    add_index :webauthn_credentials, [:user_id, :last_used_at]
+    add_index :webauthn_credentials, :authenticator_type
+    add_index :webauthn_credentials, :last_used_at
+  end
+end

db/migrate/20251104042206_add_webauthn_to_users.rb

@@ -0,0 +1,16 @@
+class AddWebauthnToUsers < ActiveRecord::Migration[8.1]
+  def change
+    # WebAuthn user handle - stable, opaque identifier for the user
+    # Must be unique and never change once assigned
+    add_column :users, :webauthn_id, :string
+    add_index :users, :webauthn_id, unique: true
+
+    # Policy enforcement - whether this user MUST use WebAuthn
+    # Can be set by admins for high-security accounts
+    add_column :users, :webauthn_required, :boolean, default: false, null: false
+
+    # User preference for 2FA method (if both TOTP and WebAuthn are available)
+    # :totp, :webauthn, or nil for system default
+    add_column :users, :preferred_2fa_method, :string
+  end
+end

db/schema.rb

@@ -10,7 +10,7 @@
 #
 # It's strongly recommended that you check this file into your version control system.
 
-ActiveRecord::Schema[8.1].define(version: 2025_11_04_022439) do
+ActiveRecord::Schema[8.1].define(version: 2025_11_04_042206) do
   create_table "application_groups", force: :cascade do |t|
     t.integer "application_id", null: false
     t.datetime "created_at", null: false
@@ -130,12 +130,38 @@ ActiveRecord::Schema[8.1].define(version: 2025_11_04_022439) do
     t.datetime "last_sign_in_at"
     t.string "name"
     t.string "password_digest", null: false
+    t.string "preferred_2fa_method"
     t.integer "status", default: 0, null: false
     t.boolean "totp_required", default: false, null: false
     t.string "totp_secret"
     t.datetime "updated_at", null: false
+    t.string "webauthn_id"
+    t.boolean "webauthn_required", default: false, null: false
     t.index ["email_address"], name: "index_users_on_email_address", unique: true
     t.index ["status"], name: "index_users_on_status"
+    t.index ["webauthn_id"], name: "index_users_on_webauthn_id", unique: true
+  end
+
+  create_table "webauthn_credentials", force: :cascade do |t|
+    t.string "authenticator_type"
+    t.boolean "backup_eligible", default: false
+    t.boolean "backup_state", default: false
+    t.datetime "created_at", null: false
+    t.string "external_id", null: false
+    t.datetime "last_used_at"
+    t.string "last_used_ip"
+    t.string "nickname"
+    t.string "public_key", null: false
+    t.integer "sign_count", default: 0, null: false
+    t.datetime "updated_at", null: false
+    t.string "user_agent"
+    t.integer "user_id", null: false
+    t.index ["authenticator_type"], name: "index_webauthn_credentials_on_authenticator_type"
+    t.index ["external_id"], name: "index_webauthn_credentials_on_external_id", unique: true
+    t.index ["last_used_at"], name: "index_webauthn_credentials_on_last_used_at"
+    t.index ["user_id", "external_id"], name: "index_webauthn_credentials_on_user_id_and_external_id", unique: true
+    t.index ["user_id", "last_used_at"], name: "index_webauthn_credentials_on_user_id_and_last_used_at"
+    t.index ["user_id"], name: "index_webauthn_credentials_on_user_id"
   end
 
   add_foreign_key "application_groups", "applications"
@@ -149,4 +175,5 @@ ActiveRecord::Schema[8.1].define(version: 2025_11_04_022439) do
   add_foreign_key "sessions", "users"
   add_foreign_key "user_groups", "groups"
   add_foreign_key "user_groups", "users"
+  add_foreign_key "webauthn_credentials", "users"
 end