array index whitelist/blacklist

1 files changed, 39 insertions, 1 deletions

diff --git a/ifilter.c b/ifilter.c
index 48b62c7..4ea846f 100644
--- a/ifilter.c
+++ b/ifilter.c
@@ -41,6 +41,26 @@ static size_t strnlen(const char *s, size_t maxlen) {
 }
 #endif
 
+static size_t strnspn(const char *input, size_t n, const char *accept)
+{
+        size_t count = 0;
+        for (; *input != '\0' && count < n; input++, count++) {
+                if (strchr(accept, *input) == NULL)
+                        break;
+        }
+        return count;
+}
+
+static size_t strncspn(const char *input, size_t n, const char *reject)
+{
+        size_t count = 0;
+        for (; *input != '\0' && count < n; input++, count++) {
+                if (strchr(reject, *input) != NULL)
+                        break;
+        }
+        return count;
+}
+
 
 /* {{{ normalize_varname
  */
@@ -524,7 +544,8 @@ unsigned int suhosin_input_filter(int arg, char *var, char **val, unsigned int v
                 }
                 
                 index_length = index_end - index;
-                        
+                
+                /* max. array index length */
                 if (SUHOSIN_G(max_array_index_length) && SUHOSIN_G(max_array_index_length) < index_length) {
                         suhosin_log(S_VARS, "configured request variable array index length limit exceeded - dropped variable '%s'", var);
                         if (!SUHOSIN_G(simulation)) {
@@ -558,6 +579,23 @@ unsigned int suhosin_input_filter(int arg, char *var, char **val, unsigned int v
                                 break;
                 }
                 
+                /* index whitelist/blacklist */
+                if (SUHOSIN_G(array_index_whitelist) && *(SUHOSIN_G(array_index_whitelist))) {
+                        if (strnspn(index, index_length, SUHOSIN_G(array_index_whitelist)) != index_length) {
+                                suhosin_log(S_VARS, "array index contains not whitelisted characters - dropped variable '%s'", var);
+                                if (!SUHOSIN_G(simulation)) {
+                                        return 0;
+                                }
+                        }
+                } else if (SUHOSIN_G(array_index_blacklist) && *(SUHOSIN_G(array_index_blacklist))) {
+                        if (strncspn(index, index_length, SUHOSIN_G(array_index_blacklist)) != index_length) {
+                                suhosin_log(S_VARS, "array index contains blacklisted characters - dropped variable '%s'", var);
+                                if (!SUHOSIN_G(simulation)) {
+                                        return 0;
+                                }
+                        }
+                }
+                
                 index = strchr(index, '[');
         }