engine: Don't follow redirects an infinite number of times

robinlinden · Nov 16, 2023 · 0fd4d8d · 0fd4d8d
1 parent 4123e2c
commit 0fd4d8d
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Showing 2 changed files with 19 additions and 0 deletions.
diff --git a/engine/engine.cpp b/engine/engine.cpp
@@ -133,12 +133,16 @@ void Engine::on_navigation_success() {
 }
 
 Engine::LoadResult Engine::load(uri::Uri uri) {
+    static constexpr int kMaxRedirects = 10;
+
     auto is_redirect = [](int status_code) {
         return status_code == 301 || status_code == 302 || status_code == 307 || status_code == 308;
     };
 
+    int redirect_count = 0;
     protocol::Response response = protocol_handler_->handle(uri);
     while (response.err == protocol::Error::Ok && is_redirect(response.status_line.status_code)) {
+        ++redirect_count;
         auto location = response.headers.get("Location");
         if (!location) {
             response.err = protocol::Error::InvalidResponse;
@@ -148,6 +152,10 @@ Engine::LoadResult Engine::load(uri::Uri uri) {
         spdlog::info("Following {} redirect from {} to {}", response.status_line.status_code, uri.uri, *location);
         uri = uri::Uri::parse(std::string(*location), uri);
         response = protocol_handler_->handle(uri);
+        if (redirect_count > kMaxRedirects) {
+            response.err = protocol::Error::RedirectLimit;
+            return {std::move(response), std::move(uri)};
+        }
     }
 
     return {std::move(response), std::move(uri)};

diff --git a/engine/engine_test.cpp b/engine/engine_test.cpp
@@ -418,5 +418,16 @@ int main() {
         expect(contains(e.stylesheet().rules, {.selectors{"p"}, .declarations{{css::PropertyId::Color, "green"}}}));
     });
 
+    etest::test("redirect loop", [] {
+        std::map<std::string, Response> responses;
+        responses["hax://example.com"s] = Response{
+                .err = Error::Ok,
+                .status_line = {.status_code = 301},
+                .headers = {{"Location", "hax://example.com"}},
+        };
+        engine::Engine e{std::make_unique<FakeProtocolHandler>(std::move(responses))};
+        expect_eq(e.navigate(uri::Uri::parse("hax://example.com")), protocol::Error::RedirectLimit);
+    });
+
     return etest::run_all_tests();
 }