Make pac parsing more robust (#27)

Ensure that the pac data is NULL-terminated and handle pac parser error.

6 files changed, 22 insertions, 14 deletions

diff --git a/src/backend/plugins/download-curl/download-curl.c b/src/backend/plugins/download-curl/download-curl.c
index 06a91b8..25228bf 100644
--- a/src/backend/plugins/download-curl/download-curl.c
+++ b/src/backend/plugins/download-curl/download-curl.c
@@ -52,10 +52,11 @@ store_data (void   *contents,
             size_t  nmemb,
             void   *user_pointer)
 {
-  GString *string = user_pointer;
+  GByteArray *byte_array = user_pointer;
   size_t real_size = size * nmemb;
 
-  g_string_append_len (string, contents, real_size);
+  g_byte_array_append (byte_array, contents, real_size);
+
   return real_size;
 }
 
@@ -64,9 +65,8 @@ px_download_curl_download (PxDownload *download,
                            const char *uri)
 {
   PxDownloadCurl *self = PX_DOWNLOAD_CURL (download);
-  g_autoptr (GBytes) bytes = NULL;
+  GByteArray *byte_array = g_byte_array_new ();
   CURLcode res;
-  g_autoptr (GString) data = g_string_new ("");
   const char *url = uri;
 
   if (g_str_has_prefix (url, "pac+"))
@@ -74,7 +74,7 @@ px_download_curl_download (PxDownload *download,
 
   curl_easy_setopt (self->curl, CURLOPT_URL, url);
   curl_easy_setopt (self->curl, CURLOPT_WRITEFUNCTION, store_data);
-  curl_easy_setopt (self->curl, CURLOPT_WRITEDATA, data);
+  curl_easy_setopt (self->curl, CURLOPT_WRITEDATA, byte_array);
 
   res = curl_easy_perform (self->curl);
   if (res != CURLE_OK) {
@@ -82,7 +82,7 @@ px_download_curl_download (PxDownload *download,
     return NULL;
   }
 
-  return g_steal_pointer (&bytes);
+  return g_byte_array_free_to_bytes (byte_array);
 }
 
 static void
diff --git a/src/backend/plugins/pacrunner-duktape/pacrunner-duktape.c b/src/backend/plugins/pacrunner-duktape/pacrunner-duktape.c
index 86221f3..72f4b2b 100644
--- a/src/backend/plugins/pacrunner-duktape/pacrunner-duktape.c
+++ b/src/backend/plugins/pacrunner-duktape/pacrunner-duktape.c
@@ -147,18 +147,22 @@ px_pacrunner_duktape_class_init (PxPacRunnerDuktapeClass *klass)
   object_class->dispose = px_pacrunner_duktape_dispose;
 }
 
-static void
+static gboolean
 px_pacrunner_duktape_set_pac (PxPacRunner *pacrunner,
                               GBytes      *pac_data)
 {
   PxPacRunnerDuktape *self = PX_PACRUNNER_DUKTAPE (pacrunner);
+  gsize len;
+  gconstpointer content = g_bytes_get_data (pac_data, &len);
+  g_autoptr (GString) pac = g_string_new_len (content, len);
 
-
-  duk_push_string (self->ctx, g_bytes_get_data (pac_data, NULL));
+  duk_push_string (self->ctx, pac->str);
 
   if (duk_peval_noresult (self->ctx)) {
-    return;
+    return FALSE;
   }
+
+  return TRUE;
 }
 
 static char *
diff --git a/src/backend/px-manager.c b/src/backend/px-manager.c
index be86830..ea4411e 100644
--- a/src/backend/px-manager.c
+++ b/src/backend/px-manager.c
@@ -339,7 +339,10 @@ px_manager_run_pac (PeasExtensionSet *set,
   struct PacData *pac_data = data;
   char *ret;
 
-  ifc->set_pac (PX_PAC_RUNNER (extension), pac_data->pac);
+  if (!ifc->set_pac (PX_PAC_RUNNER (extension), pac_data->pac)) {
+    return;
+  }
+
   ret = ifc->run (PX_PAC_RUNNER (extension), pac_data->uri);
   if (ret)
     g_strv_builder_add (pac_data->builder, ret);
diff --git a/src/backend/px-plugin-pacrunner.h b/src/backend/px-plugin-pacrunner.h
index 2b38c40..0226dc0 100644
--- a/src/backend/px-plugin-pacrunner.h
+++ b/src/backend/px-plugin-pacrunner.h
@@ -34,7 +34,7 @@ struct _PxPacRunnerInterface
 {
   GTypeInterface parent_iface;
 
-  void (*set_pac) (PxPacRunner *pacrunner, GBytes *pac_data);
+  gboolean (*set_pac) (PxPacRunner *pacrunner, GBytes *pac_data);
   char *(*run) (PxPacRunner *self, GUri *uri);
 };
 
diff --git a/src/tests/data/px-manager-sample.pac b/src/tests/data/px-manager-sample.pac
index 48d01f0..b86c555 100644
--- a/src/tests/data/px-manager-sample.pac
+++ b/src/tests/data/px-manager-sample.pac
@@ -3,4 +3,4 @@ function FindProxyForURL(url, host)
   var myIP = myIpAddress();
 
   return "PROXY 127.0.0.1:1983"
-}
\ No newline at end of file
+}
diff --git a/src/tests/px-manager-test.c b/src/tests/px-manager-test.c
index 428f5d2..afab118 100644
--- a/src/tests/px-manager-test.c
+++ b/src/tests/px-manager-test.c
@@ -38,6 +38,7 @@ server_callback (SoupServer        *server,
                  GHashTable        *query,
                  gpointer           data)
 {
+  g_print ("%s: path %s\n", __FUNCTION__, path);
   soup_server_message_set_status (SOUP_SERVER_MESSAGE (msg), SOUP_STATUS_OK, NULL);
 
   if (g_strcmp0 (path, "/test.pac") == 0) {
@@ -85,7 +86,7 @@ download_pac (gpointer data)
   Fixture *self = data;
   GBytes *pac;
 
-  pac = px_manager_pac_download (self->manager, "http://127.0.0.1:1983");
+  pac = px_manager_pac_download (self->manager, "http://127.0.0.1:1983/test.pac");
   g_assert_nonnull (pac);
 
   g_main_loop_quit (self->loop);