respect response length when looking for error message (#324)

src/rapi/rc_api_common.c

@@ -37,6 +37,24 @@ static void rc_json_skip_whitespace(rc_json_iterator_t* iterator)
     ++iterator->json;
 }
 
+static int rc_json_find_substring(rc_json_iterator_t* iterator, const char* substring)
+{
+  const char first = *substring;
+  const size_t substring_len = strlen(substring);
+  const char* end = iterator->end - substring_len;
+
+  while (iterator->json <= end) {
+    if (*iterator->json == first) {
+      if (memcmp(iterator->json, substring, substring_len) == 0)
+        return 1;
+    }
+
+    ++iterator->json;
+  }
+
+  return 0;
+}
+
 static int rc_json_find_closing_quote(rc_json_iterator_t* iterator)
 {
   while (iterator->json < iterator->end) {
@@ -237,43 +255,48 @@ int rc_json_get_next_object_field(rc_json_iterator_t* iterator, rc_json_field_t*
 }
 
 int rc_json_get_object_string_length(const char* json) {
-  const char* json_start = json;
-
   rc_json_iterator_t iterator;
   memset(&iterator, 0, sizeof(iterator));
   iterator.json = json;
   iterator.end = json + (1024 * 1024 * 1024); /* arbitrary 1GB limit on JSON response */
 
   rc_json_parse_object(&iterator, NULL, 0, NULL);
 
-  return (int)(iterator.json - json_start);
+  if (iterator.json == json) /* not JSON */
+    return (int)strlen(json);
+
+  return (int)(iterator.json - json);
 }
 
 static int rc_json_extract_html_error(rc_api_response_t* response, const rc_api_server_response_t* server_response) {
-  const char* json = server_response->body;
-  const char* end = json;
-
-  const char* title_start = strstr(json, "<title>");
-  if (title_start) {
-    title_start += 7;
-    if (isdigit((int)*title_start)) {
-      const char* title_end = strstr(title_start + 7, "</title>");
-      if (title_end) {
-        response->error_message = rc_buffer_strncpy(&response->buffer, title_start, title_end - title_start);
-        response->succeeded = 0;
-        return RC_INVALID_JSON;
-      }
+  rc_json_iterator_t iterator;
+  memset(&iterator, 0, sizeof(iterator));
+  iterator.json = server_response->body;
+  iterator.end = server_response->body + server_response->body_length;
+
+  /* if the title contains an HTTP status code(i.e "404 Not Found"), return the title */
+  if (rc_json_find_substring(&iterator, "<title>")) {
+    const char* title_start = iterator.json + 7;
+    if (isdigit((int)*title_start) && rc_json_find_substring(&iterator, "</title>")) {
+      response->error_message = rc_buffer_strncpy(&response->buffer, title_start, iterator.json - title_start);
+      response->succeeded = 0;
+      return RC_INVALID_JSON;
     }
   }
 
-  while (*end && *end != '\n' && end - json < 200)
-    ++end;
+  /* title not found, or did not start with an error code, return the first line of the response */
+  iterator.json = server_response->body;
+
+  while (iterator.json < iterator.end && *iterator.json != '\n' &&
+         iterator.json - server_response->body < 200) {
+    ++iterator.json;
+  }
 
-  if (end > json && end[-1] == '\r')
-    --end;
+  if (iterator.json > server_response->body && iterator.json[-1] == '\r')
+    --iterator.json;
 
-  if (end > json)
-    response->error_message = rc_buffer_strncpy(&response->buffer, json, end - json);
+  if (iterator.json > server_response->body)
+    response->error_message = rc_buffer_strncpy(&response->buffer, server_response->body, iterator.json - server_response->body);
 
   response->succeeded = 0;
   return RC_INVALID_JSON;

test/rapi/test_rc_api_common.c

@@ -90,6 +90,30 @@ static void test_json_parse_response_non_json() {
   ASSERT_NUM_EQUALS(response.succeeded, 0);
 }
 
+static void test_json_parse_response_non_json_bounded() {
+  int result;
+  rc_api_server_response_t server_response;
+  rc_api_response_t response;
+  const char* error_message = "This is an error.\r\n<title>Should not be seen</title>";
+  rc_json_field_t fields[] = {
+    RC_JSON_NEW_FIELD("Success"),
+    RC_JSON_NEW_FIELD("Error"),
+    RC_JSON_NEW_FIELD("Test")
+  };
+  rc_buffer_init(&response.buffer);
+
+  memset(&server_response, 0, sizeof(server_response));
+  server_response.body = error_message;
+  server_response.body_length = 16; /* "This is an error" (no period, newline, etc) */
+
+  result = rc_json_parse_server_response(&response, &server_response, fields, sizeof(fields) / sizeof(fields[0]));
+  ASSERT_NUM_EQUALS(result, RC_INVALID_JSON);
+
+  ASSERT_PTR_NOT_NULL(response.error_message);
+  ASSERT_STR_EQUALS(response.error_message, "This is an error");
+  ASSERT_NUM_EQUALS(response.succeeded, 0);
+}
+
 static void test_json_parse_response_error_from_server() {
   int result;
   rc_api_server_response_t server_response;
@@ -766,6 +790,7 @@ void test_rapi_common(void) {
   TEST_PARAMS2(test_json_parse_response_field, "{ \"Other\" : 1, \"Test\" : 2 }", "2"); /* preceding field */
   TEST_PARAMS2(test_json_parse_response_field, "{ \"Test\" : 1, \"Other\" : 2 }", "1"); /* trailing field */
   TEST(test_json_parse_response_non_json);
+  TEST(test_json_parse_response_non_json_bounded);
   TEST(test_json_parse_response_error_from_server);
   TEST(test_json_parse_response_incorrect_size);
 

test/rapi/test_rc_api_runtime.c

@@ -951,6 +951,23 @@ static void test_process_award_achievement_response_503_fancy() {
   rc_api_destroy_award_achievement_response(&award_achievement_response);
 }
 
+static void test_process_award_achievement_response_522_simple() {
+  rc_api_award_achievement_response_t award_achievement_response;
+  const char* server_response = "error code: 522";
+
+  memset(&award_achievement_response, 0, sizeof(award_achievement_response));
+
+  ASSERT_NUM_EQUALS(rc_api_process_award_achievement_response(&award_achievement_response, server_response), RC_INVALID_JSON);
+  ASSERT_NUM_EQUALS(award_achievement_response.response.succeeded, 0);
+  ASSERT_STR_EQUALS(award_achievement_response.response.error_message, "error code: 522");
+  ASSERT_UNUM_EQUALS(award_achievement_response.new_player_score, 0);
+  ASSERT_UNUM_EQUALS(award_achievement_response.new_player_score_softcore, 0);
+  ASSERT_UNUM_EQUALS(award_achievement_response.awarded_achievement_id, 0);
+  ASSERT_UNUM_EQUALS(award_achievement_response.achievements_remaining, 0);
+
+  rc_api_destroy_award_achievement_response(&award_achievement_response);
+}
+
 static void test_init_submit_lboard_entry_request() {
   rc_api_submit_lboard_entry_request_t submit_lboard_entry_request;
   rc_api_request_t request;
@@ -1164,6 +1181,7 @@ void test_rapi_runtime(void) {
   TEST(test_process_award_achievement_response_429);
   TEST(test_process_award_achievement_response_429_json);
   TEST(test_process_award_achievement_response_503_fancy);
+  TEST(test_process_award_achievement_response_522_simple);
 
   /* submitlbentry */
   TEST(test_init_submit_lboard_entry_request);