lockdown: Fix error parsing for older iOS versions

A logical bug did prevent parsing the 'Error' node since the code
path is never reached when a 'Result' node is found first. This
is mitigated by always checking for the 'Error' node first.

1 files changed, 19 insertions, 35 deletions

diff --git a/src/lockdown.c b/src/lockdown.c
index 505b13e..92af186 100644
--- a/src/lockdown.c
+++ b/src/lockdown.c
@@ -165,51 +165,38 @@ lockdownd_error_t lockdown_check_result(plist_t dict, const char *query_match)
                 return ret;
         }
 
-        char *query_value = NULL;
-
-        plist_get_string_val(query_node, &query_value);
+        const char *query_value = plist_get_string_ptr(query_node, NULL);
         if (!query_value) {
                 return ret;
         }
 
         if (query_match && (strcmp(query_value, query_match) != 0)) {
-                free(query_value);
                 return ret;
         }
 
-        free(query_value);
-
-        plist_t result_node = plist_dict_get_item(dict, "Result");
-        if (!result_node) {
-                /* iOS 5: the 'Result' key is not present anymore.
-                   But we need to check for the 'Error' key. */
-                plist_t err_node = plist_dict_get_item(dict, "Error");
-                if (err_node) {
-                        if (plist_get_node_type(err_node) == PLIST_STRING) {
-                                char *err_value = NULL;
-
-                                plist_get_string_val(err_node, &err_value);
-                                if (err_value) {
-                                        debug_info("ERROR: %s", err_value);
-                                        ret = lockdownd_strtoerr(err_value);
-                                        free(err_value);
-                                } else {
-                                        debug_info("ERROR: unknown error occurred");
-                                }
+        /* Check for 'Error' in reply */
+        plist_t err_node = plist_dict_get_item(dict, "Error");
+        if (err_node) {
+                if (plist_get_node_type(err_node) == PLIST_STRING) {
+                        const char *err_value = plist_get_string_ptr(err_node, NULL);
+                        if (err_value) {
+                                debug_info("ERROR: %s", err_value);
+                                ret = lockdownd_strtoerr(err_value);
+                        } else {
+                                debug_info("ERROR: unknown error occurred");
                         }
-                        return ret;
                 }
-
-                ret = LOCKDOWN_E_SUCCESS;
-
                 return ret;
         }
 
-        plist_type result_type = plist_get_node_type(result_node);
-        if (result_type == PLIST_STRING) {
-                char *result_value = NULL;
-
-                plist_get_string_val(result_node, &result_value);
+        plist_t result_node = plist_dict_get_item(dict, "Result");
+        if (!result_node) {
+                /* With iOS 5+ 'Result' is not present anymore.
+                   If there is no 'Error', we can just assume success. */
+                return LOCKDOWN_E_SUCCESS;
+        }
+        if (plist_get_node_type(result_node) == PLIST_STRING) {
+                const char *result_value = plist_get_string_ptr(result_node, NULL);
                 if (result_value) {
                         if (!strcmp(result_value, "Success")) {
                                 ret = LOCKDOWN_E_SUCCESS;
@@ -219,9 +206,6 @@ lockdownd_error_t lockdown_check_result(plist_t dict, const char *query_match)
                                 debug_info("ERROR: unknown result value '%s'", result_value);
                         }
                 }
-
-                if (result_value)
-                        free(result_value);
         }
 
         return ret;