Handle untrusted validation

brave · Jan 8, 2025 · 6f59fdb · 6f59fdb
1 parent d4aa01d
commit 6f59fdb
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Showing 5 changed files with 72 additions and 17 deletions.
diff --git a/chromium_src/ios/web/public/web_client.h b/chromium_src/ios/web/public/web_client.h
@@ -2,10 +2,11 @@
 #include <WebKit/WebKit.h>
 
 #include "ios/web/webui/mojo_facade.h"
+#include "ios/web/public/web_state.h"
 
 #define IsBrowserLockdownModeEnabled                                         \
   IsWebUIMessageAllowedForFrame(WKFrameInfo* frame, const GURL& origin,      \
-                                NSString** prompt, web::MojoFacade* facade); \
+                                NSString** prompt, web::MojoFacade* facade, web::WebState* webState); \
   virtual bool IsBrowserLockdownModeEnabled
 
 #include "src/ios/web/public/web_client.h"

diff --git a/chromium_src/ios/web/web_client.mm b/chromium_src/ios/web/web_client.mm
@@ -3,7 +3,7 @@
 
 #define IsBrowserLockdownModeEnabled                                          \
   IsWebUIMessageAllowedForFrame(WKFrameInfo* frame, const GURL& origin,       \
-                                NSString** prompt, web::MojoFacade* facade) { \
+                                NSString** prompt, web::MojoFacade* facade, web::WebState* webState) { \
     return false;                                                             \
   }                                                                           \
   bool WebClient::IsBrowserLockdownModeEnabled

diff --git a/chromium_src/ios/web/web_state/ui/crw_wk_ui_handler.mm b/chromium_src/ios/web/web_state/ui/crw_wk_ui_handler.mm
@@ -5,7 +5,7 @@
 
 #define IsAppSpecificURL(URL)                                                  \
   IsAppSpecificURL(URL) && web::GetWebClient()->IsWebUIMessageAllowedForFrame( \
-                               frame, origin, &prompt, self.mojoFacade)
+                               frame, origin, &prompt, self.mojoFacade, self.webStateImpl)
 
 #include "src/ios/web/web_state/ui/crw_wk_ui_handler.mm"
 

diff --git a/ios/browser/brave_web_client.h b/ios/browser/brave_web_client.h
@@ -9,6 +9,8 @@
 #include <memory>
 #include <string>
 #include <vector>
+#include <map>
+#include "base/functional/callback_forward.h"
 
 #include "ios/chrome/browser/web/model/chrome_web_client.h"
 
@@ -41,10 +43,26 @@ class BraveWebClient : public ChromeWebClient {
   bool IsWebUIMessageAllowedForFrame(WKFrameInfo* frame,
                                      const GURL& origin,
                                      NSString** prompt,
-                                     web::MojoFacade* facade) override;
+                                     web::MojoFacade* facade, web::WebState* webState) override;
+
+  template<typename Interface>
+  void RegisterUntrustedInterface(base::RepeatingCallback<void(mojo::PendingReceiver<Interface>)>
+                                  callback) {
+    untrusted_bindings_.emplace(std::string(Interface::Name_), base::BindRepeating(&WrapCallback<Interface>, std::move(callback)));
+  }
 
  private:
   std::string user_agent_;
+  std::map<std::string, base::RepeatingCallback<void(mojo::GenericPendingReceiver*)>> untrusted_bindings_;
+
+  template <typename Interface>
+  static void WrapCallback(
+      base::RepeatingCallback<void(mojo::PendingReceiver<Interface>)>
+          callback,
+      mojo::GenericPendingReceiver* receiver) {
+    if (auto typed_receiver = receiver->As<Interface>())
+      callback.Run(std::move(typed_receiver));
+  }
 };
 
 #endif  // BRAVE_IOS_BROWSER_BRAVE_WEB_CLIENT_H_
diff --git a/ios/browser/brave_web_client.mm b/ios/browser/brave_web_client.mm
@@ -14,6 +14,12 @@
 #import "ios/web/public/navigation/browser_url_rewriter.h"
 #include "url/gurl.h"
 
+#include "ios/web/public/thread/web_thread.h"
+#include "ios/web/webui/mojo_facade.h"
+#include "base/strings/sys_string_conversions.h"
+#include "base/json/json_reader.h"
+#include "net/base/apple/url_conversions.h"
+
 #if !defined(__has_feature) || !__has_feature(objc_arc)
 #error "This file requires ARC support."
 #endif
@@ -84,26 +90,56 @@ bool WillHandleBraveURLRedirect(GURL* url, web::BrowserState* browser_state) {
 bool BraveWebClient::IsWebUIMessageAllowedForFrame(WKFrameInfo* frame,
                                                    const GURL& origin,
                                                    NSString** prompt,
-                                                   web::MojoFacade* facade) {
-  /*DCHECK_CURRENTLY_ON(WebThread::UI);
+                                                   web::MojoFacade* facade,
+                                                   web::WebState* webState) {
+  DCHECK_CURRENTLY_ON(web::WebThread::UI);
   CHECK(prompt && *prompt);
 
-  MessageNameAndArguments name_and_args =
-      GetMessageNameAndArguments(base::SysNSStringToUTF8(*prompt));
+  auto GetMessageNameAndArguments = [](
+      const std::string& mojo_message_as_json) -> std::pair<std::string, base::Value::Dict> {
+    auto value_with_error = base::JSONReader::ReadAndReturnValueWithError(
+        mojo_message_as_json, base::JSON_PARSE_RFC);
+    CHECK(value_with_error.has_value());
+    CHECK(value_with_error->is_dict());
 
-  if (name_and_args.name == "Mojo.bindInterface") {
-    const base::Value::Dict& args name_and_args.args;
+    base::Value::Dict& dict = value_with_error->GetDict();
+    const std::string* name = dict.FindString("name");
+    CHECK(name);
 
-    const std::string* interface_name = args.FindString("interfaceName");
-    CHECK(interface_name);
+    base::Value::Dict* args = dict.FindDict("args");
+    CHECK(args);
 
-    // VALIDATE interface_name
+    return {*name, std::move(*args)};
+  };
 
-  }*/
+  auto name_and_args =
+      GetMessageNameAndArguments(base::SysNSStringToUTF8(*prompt));
 
-  // Must return an invalid message name
-  //  *prompt = @"{\"name\":\"Mojo.invalidInterface\", args:{}}";
+  // If the scheme is untrusted
+  if (name_and_args.first == "Mojo.bindInterface" &&
+      origin.scheme() == "chrome-untrusted") {
+    const base::Value::Dict& args = name_and_args.second;
+
+    const std::string* interface_name = args.FindString("interfaceName");
+    CHECK(interface_name);
+
+    // Get the request and validate that a chrome-untrusted:// can't access chrome://
+    GURL request_url = net::GURLWithNSURL(frame.request.URL);
+    if (request_url.scheme() == "chrome") {
+      *prompt = @"{\"name\":\"Mojo.invalidRequest\",\"args\":{}}";
+      return true;
+    }
+
+    // Check if the requested interface is registered
+    if (auto it = untrusted_bindings_.find(*interface_name); it != untrusted_bindings_.end()) {
+      webState->GetInterfaceBinderForMainFrame()->AddInterface(it->first, it->second);
+      return true;
+    }
+
+    NSLog(@"INTERFACE NOT FOUND!\n");
+    *prompt = @"{\"name\":\"Mojo.invalidInterface\",\"args\":{}}";
+    return true;
+  }
 
-  NSLog(@"PROMPT RECEIVED: %@", *prompt);
   return true;
 }