feat: message broker for user scripts

Package.swift

@@ -130,7 +130,10 @@ let package = Package(
  .define("TERMINATE_WITH_REASON_ENABLED", .when(platforms: [.macOS])),
  ]),
  .target(
- name: "UserScript"
+ name: "UserScript",
+ dependencies: [
+ "Common"
+ ]
  ),
  .target(
  name: "PrivacyDashboard",
@@ -160,7 +163,7 @@ let package = Package(
  dependencies: [
  "Networking"
  ]),
- 
+
  // MARK: - Test targets
  .testTarget(
  name: "BrowserServicesKitTests",

Sources/BrowserServicesKit/ContentScopeScript/ContentScopeUserScript.swift

@@ -21,6 +21,8 @@ import WebKit
 import Combine
 import ContentScopeScripts
 import UserScript
+import Common
+import os.log
 
 public final class ContentScopeProperties: Encodable {
  public let globalPrivacyControlValue: Bool
@@ -38,9 +40,9 @@ public final class ContentScopeProperties: Encodable {
  }
 }
 public struct ContentScopeFeature: Encodable {
- 
+
  public let settings: [String: ContentScopeFeatureToggles]
- 
+
  public init(featureToggles: ContentScopeFeatureToggles) {
  self.settings = ["featureToggles": featureToggles]
  }
@@ -49,18 +51,18 @@ public struct ContentScopeFeature: Encodable {
 public struct ContentScopeFeatureToggles: Encodable {
 
  public let emailProtection: Bool
- 
+
  public let credentialsAutofill: Bool
  public let identitiesAutofill: Bool
  public let creditCardsAutofill: Bool
- 
+
  public let credentialsSaving: Bool
- 
+
  public let passwordGeneration: Bool
- 
+
  public let inlineIconCredentials: Bool
  public let thirdPartyCredentialsProvider: Bool
- 
+
  // Explicitly defined memberwise init only so it can be public
  public init(emailProtection: Bool,
  credentialsAutofill: Bool,
@@ -70,7 +72,7 @@ public struct ContentScopeFeatureToggles: Encodable {
  passwordGeneration: Bool,
  inlineIconCredentials: Bool,
  thirdPartyCredentialsProvider: Bool) {
- 
+
  self.emailProtection = emailProtection
  self.credentialsAutofill = credentialsAutofill
  self.identitiesAutofill = identitiesAutofill
@@ -80,18 +82,18 @@ public struct ContentScopeFeatureToggles: Encodable {
  self.inlineIconCredentials = inlineIconCredentials
  self.thirdPartyCredentialsProvider = thirdPartyCredentialsProvider
  }
- 
+
  enum CodingKeys: String, CodingKey {
  case emailProtection = "emailProtection"
- 
+
  case credentialsAutofill = "inputType_credentials"
  case identitiesAutofill = "inputType_identities"
  case creditCardsAutofill = "inputType_creditCards"
- 
+
  case credentialsSaving = "credentials_saving"
- 
+
  case passwordGeneration = "password_generation"
- 
+
  case inlineIconCredentials = "inlineIcon_credentials"
  case thirdPartyCredentialsProvider = "third_party_credentials_provider"
  }
@@ -107,38 +109,114 @@ public struct ContentScopePlatform: Encodable {
  #endif
 }
 
-public final class ContentScopeUserScript: NSObject, UserScript {
- public let messageNames: [String] = []
+public final class ContentScopeUserScript: NSObject, UserScript, UserScriptMessaging {
+
+ public var broker: UserScriptMessageBroker;
+ public let isolated: Bool
+ public var messageNames: [String] = []
 
- public init(_ privacyConfigManager: PrivacyConfigurationManaging, properties: ContentScopeProperties) {
- source = ContentScopeUserScript.generateSource(privacyConfigManager, properties: properties)
+ public init(_ privacyConfigManager: PrivacyConfigurationManaging,
+ properties: ContentScopeProperties,
+ isolated: Bool = false
+ ) {
+ self.isolated = isolated
+ let contextName = self.isolated ? "contentScopeScriptsIsolated" : "contentScopeScripts";
+ self.broker = UserScriptMessageBroker(context: contextName)
+
+ source = ContentScopeUserScript.generateSource(
+ privacyConfigManager,
+ properties: properties,
+ isolated: self.isolated,
+ config: self.broker.messagingConfig()
+ )
+ self.messageNames = [contextName]
  }
 
- public static func generateSource(_ privacyConfigurationManager: PrivacyConfigurationManaging, properties: ContentScopeProperties) -> String {
+ public static func generateSource(_ privacyConfigurationManager: PrivacyConfigurationManaging,
+ properties: ContentScopeProperties,
+ isolated: Bool,
+ config: WebkitMessagingConfig
+ ) -> String {
 
  guard let privacyConfigJson = String(data: privacyConfigurationManager.currentConfig, encoding: .utf8),
  let userUnprotectedDomains = try? JSONEncoder().encode(privacyConfigurationManager.privacyConfig.userUnprotectedDomains),
  let userUnprotectedDomainsString = String(data: userUnprotectedDomains, encoding: .utf8),
  let jsonProperties = try? JSONEncoder().encode(properties),
- let jsonPropertiesString = String(data: jsonProperties, encoding: .utf8)
+ let jsonPropertiesString = String(data: jsonProperties, encoding: .utf8),
+ let jsonConfig = try? JSONEncoder().encode(config),
+ let jsonConfigString = String(data: jsonConfig, encoding: .utf8)
  else {
  return ""
  }
-
- return loadJS("contentScope", from: ContentScopeScripts.Bundle, withReplacements: [
+
+ let jsInclude = isolated ? "contentScopeIsolated" : "contentScope"
+
+ return loadJS(jsInclude, from: ContentScopeScripts.Bundle, withReplacements: [
  "$CONTENT_SCOPE$": privacyConfigJson,
  "$USER_UNPROTECTED_DOMAINS$": userUnprotectedDomainsString,
- "$USER_PREFERENCES$": jsonPropertiesString
+ "$USER_PREFERENCES$": jsonPropertiesString,
+ "$WEBKIT_MESSAGING_CONFIG$": jsonConfigString
  ])
  }
 
- public func userContentController(_ userContentController: WKUserContentController, didReceive message: WKScriptMessage) {
- }
-
  public let source: String
-
  public let injectionTime: WKUserScriptInjectionTime = .atDocumentStart
  public let forMainFrameOnly: Bool = false
- public let requiresRunInPageContentWorld: Bool = true
+ public var requiresRunInPageContentWorld: Bool {
+ if #available(macOS 11.0, *) {
+ if self.isolated { return false }
+ }
+ return true
+ }
+}
+
+@available(macOS 11, *)
+extension ContentScopeUserScript: WKScriptMessageHandlerWithReply {
+ public func userContentController(_ userContentController: WKUserContentController,
+ didReceive message: WKScriptMessage,
+ replyHandler: @escaping (Any?, String?) -> Void) {
+ let action = broker.messageHandlerFor(message)
+ do {
+ try broker.execute(action: action, original: message) { json in
+ replyHandler(json, nil)
+ }
+ } catch let error {
+ // forward uncaught errors to the client
+ replyHandler(nil, error.localizedDescription)
+ }
+ }
+}
+
+// MARK: - Fallback for macOS 10.15
+extension ContentScopeUserScript: WKScriptMessageHandler {
+ public func userContentController(_ userContentController: WKUserContentController, didReceive message: WKScriptMessage) {
+ let action = broker.messageHandlerFor(message);
+
+ if case .notify = action {
+ do {
+ try broker.execute(action: action, original: message) { _ in
+ message.webView?.evaluateJavaScript("console.log('🍎 doing nothing with notification')")
+ }
+ } catch let error {
+ // there's no way of communicating this
+ message.webView?.evaluateJavaScript("console.log('error \(error.localizedDescription)')")
+ }
+ }
 
+ // Accept a message that requires an encrypted response
+ guard case .respondEncrypted(_, _, let params) = action else {
+ message.webView?.evaluateJavaScript("console.log('not something to response to \(String(describing: message.messageBody))')")
+ return
+ }
+
+ do {
+ try broker.execute(action: action, original: message) { [weak broker] json in
+ broker?.encryptMessageResponse(response: json, params: params, message: message)
+ message.webView?.evaluateJavaScript("console.log('all good')")
+ }
+ } catch let error {
+ // there's no way of communicating this
+ message.webView?.evaluateJavaScript("console.log('cannot communicate this error: \(error.localizedDescription)')")
+ }
+ }
 }

Sources/BrowserServicesKit/ContentScopeScript/SpecialPagesUserScript.swift

@@ -0,0 +1,64 @@
+//
+// Created by shane osbourne on 22/04/2023.
+//
+
+import Foundation
+import WebKit
+import Combine
+import ContentScopeScripts
+import UserScript
+import Common
+import os.log
+
+public final class SpecialPagesUserScript: NSObject, UserScript, UserScriptMessaging {
+ public var source: String = "";
+
+ public static let context = "specialPages"
+
+ // special pages messaging cannot be isolated as we'll want regular page-scripts to be able to communicate
+ public let broker = UserScriptMessageBroker(context: SpecialPagesUserScript.context, requiresRunInPageContentWorld: true );
+
+ public let messageNames: [String] = [
+ SpecialPagesUserScript.context
+ ]
+
+ public let injectionTime: WKUserScriptInjectionTime = .atDocumentStart
+ public let forMainFrameOnly: Bool = true
+ public private(set) var requiresRunInPageContentWorld: Bool = true
+}
+
+@available(macOS 11, *)
+extension SpecialPagesUserScript: WKScriptMessageHandlerWithReply {
+ public func userContentController(_ userContentController: WKUserContentController,
+ didReceive message: WKScriptMessage,
+ replyHandler: @escaping (Any?, String?) -> Void) {
+ let action = broker.messageHandlerFor(message)
+ do {
+ try broker.execute(action: action, original: message) { json in
+ replyHandler(json, nil)
+ }
+ } catch let error {
+ // forward uncaught errors to the client
+ replyHandler(nil, error.localizedDescription)
+ }
+ }
+}
+
+// MARK: - Fallback for macOS 10.15
+extension SpecialPagesUserScript: WKScriptMessageHandler {
+ public func userContentController(_ userContentController: WKUserContentController, didReceive message: WKScriptMessage) {
+ let action = broker.messageHandlerFor(message);
+
+ // special pages only support notifications on Catalina
+ if case .notify = action {
+ do {
+ try broker.execute(action: action, original: message) { _ in
+ message.webView?.evaluateJavaScript("console.log('🍎 doing nothing with notification')")
+ }
+ } catch let error {
+ // there's no way of communicating this
+ message.webView?.evaluateJavaScript("console.log('error \(error.localizedDescription)')")
+ }
+ }
+ }
+}

Sources/UserScript/UserScriptMessageEncryption.swift

@@ -19,6 +19,14 @@
 
 import Foundation
 import WebKit
+import Common
+
+public struct SecureMessagingParams: Codable {
+ let iv: [UInt8]
+ let key: [UInt8]
+ let methodName: String
+ let secret: String
+}
 
 public protocol UserScriptMessageEncryption {
 
@@ -41,41 +49,54 @@ extension UserScriptMessageEncryption {
  return
  }
 
- guard let body = message.messageBody as? [String: Any],
- let messageHandling = body["messageHandling"] as? [String: Any],
- let secret = messageHandling["secret"] as? String,
- // If this does not match the page is playing shenanigans.
- secret == generatedSecret
- else { return }
+ guard let params = accept(encrypted: message) else { return }
 
  messageHandler(message) { reply in
- guard let reply = reply,
- let messageHandling = body["messageHandling"] as? [String: Any],
- let key = messageHandling["key"] as? [UInt8],
- let iv = messageHandling["iv"] as? [UInt8],
- let methodName = messageHandling["methodName"] as? String,
- let encryption = try? self.encrypter.encryptReply(reply, key: key, iv: iv) else { return }
-
- let ciphertext = encryption.ciphertext.withUnsafeBytes { bytes in
- return bytes.map { String($0) }
- }.joined(separator: ",")
-
- let tag = encryption.tag.withUnsafeBytes { bytes in
- return bytes.map { String($0) }
- }.joined(separator: ",")
-
- let script = """
- (() => {
- window.\(methodName) && window.\(methodName)({
- ciphertext: [\(ciphertext)],
- tag: [\(tag)]
- });
- })();
- """
-
- assert(message.messageWebView != nil)
- dispatchPrecondition(condition: .onQueue(DispatchQueue.main))
- message.messageWebView?.evaluateJavaScript(script)
+ guard let reply = reply else { return }
+ encrypt(reply: reply, with: params, into: message.messageWebView)
+ }
+ }
+
+ public func messageHandlerFor(_ messageName: String) -> MessageHandler? {
+ return nil
+ }
+
+ public func accept(encrypted message: UserScriptMessage) -> SecureMessagingParams? {
+ guard let body = message.messageBody as? [String: Any],
+ let messageHandling = body["messageHandling"],
+ let params: SecureMessagingParams = DecodableHelper.decode(from: messageHandling),
+ params.secret == generatedSecret
+ else {
+ print("doing nothing")
+ return nil
  }
+
+ return params
+ }
+
+ public func encrypt(reply: String, with params: SecureMessagingParams, into webView: WKWebView?) {
+
+ guard let encryption = try? encrypter.encryptReply(reply, key: params.key, iv: params.iv) else { return }
+
+ let ciphertext = encryption.ciphertext.withUnsafeBytes { bytes in
+ return bytes.map { String($0) }
+ }.joined(separator: ",")
+
+ let tag = encryption.tag.withUnsafeBytes { bytes in
+ return bytes.map { String($0) }
+ }.joined(separator: ",")
+
+ let script = """
+ (() => {
+ window.\(params.methodName) && window.\(params.methodName)({
+ ciphertext: [\(ciphertext)],
+ tag: [\(tag)]
+ });
+ })();
+ """
+
+ assert(webView != nil)
+ dispatchPrecondition(condition: .onQueue(DispatchQueue.main))
+ webView?.evaluateJavaScript(script)
  }
 }