blobmsg: drop old comment about json formatting functions

[oweals/libubox.git] / blob.c

diff --git a/blob.c b/blob.c
index 03d5e9c27ee73ec52bd30514a0cd6044cb7c6cf1..433becb904f54d4e0b3fb186756f62c71beb0ba5 100644 (file)
--- a/blob.c
+++ b/blob.c
@@ -186,7 +186,7 @@ blob_nest_end(struct blob_buf *buf, void *cookie)
        buf->head = attr;
 }
 
-static const int blob_type_minlen[BLOB_ATTR_LAST] = {
+static const size_t blob_type_minlen[BLOB_ATTR_LAST] = {
        [BLOB_ATTR_STRING] = 1,
        [BLOB_ATTR_INT8] = sizeof(uint8_t),
        [BLOB_ATTR_INT16] = sizeof(uint16_t),
@@ -217,44 +217,90 @@ blob_check_type(const void *ptr, unsigned int len, int type)
        return true;
 }
 
-int
-blob_parse(struct blob_attr *attr, struct blob_attr **data, const struct blob_attr_info *info, int max)
+static int
+blob_parse_attr(struct blob_attr *attr, size_t attr_len, struct blob_attr **data, const struct blob_attr_info *info, int max)
 {
-       struct blob_attr *pos;
+       int id;
+       size_t len;
        int found = 0;
-       int rem;
+       size_t data_len;
 
-       memset(data, 0, sizeof(struct blob_attr *) * max);
-       blob_for_each_attr(pos, attr, rem) {
-               int id = blob_id(pos);
-               int len = blob_len(pos);
+       if (!attr || attr_len < sizeof(struct blob_attr))
+               return 0;
 
-               if (id >= max)
-                       continue;
+       id = blob_id(attr);
+       if (id >= max)
+               return 0;
 
-               if (info) {
-                       int type = info[id].type;
+       len = blob_raw_len(attr);
+       if (len > attr_len || len < sizeof(struct blob_attr))
+               return 0;
 
-                       if (type < BLOB_ATTR_LAST) {
-                               if (!blob_check_type(blob_data(pos), len, type))
-                                       continue;
-                       }
+       data_len = blob_len(attr);
+       if (data_len > len)
+               return 0;
 
-                       if (info[id].minlen && len < info[id].minlen)
-                               continue;
+       if (info) {
+               int type = info[id].type;
 
-                       if (info[id].maxlen && len > info[id].maxlen)
-                               continue;
-
-                       if (info[id].validate && !info[id].validate(&info[id], pos))
-                               continue;
+               if (type < BLOB_ATTR_LAST) {
+                       if (!blob_check_type(blob_data(attr), data_len, type))
+                               return 0;
                }
 
-               if (!data[id])
-                       found++;
+               if (info[id].minlen && len < info[id].minlen)
+                       return 0;
+
+               if (info[id].maxlen && len > info[id].maxlen)
+                       return 0;
 
-               data[id] = pos;
+               if (info[id].validate && !info[id].validate(&info[id], attr))
+                       return 0;
        }
+
+       if (!data[id])
+               found++;
+
+       data[id] = attr;
+       return found;
+}
+
+int
+blob_parse_untrusted(struct blob_attr *attr, size_t attr_len, struct blob_attr **data, const struct blob_attr_info *info, int max)
+{
+       struct blob_attr *pos;
+       size_t len = 0;
+       int found = 0;
+       size_t rem;
+
+       if (!attr || attr_len < sizeof(struct blob_attr))
+               return 0;
+
+       len = blob_raw_len(attr);
+       if (attr_len < len)
+               return 0;
+
+       memset(data, 0, sizeof(struct blob_attr *) * max);
+       blob_for_each_attr_len(pos, attr, len, rem) {
+               found += blob_parse_attr(pos, rem, data, info, max);
+       }
+
+       return found;
+}
+
+/* use only on trusted input, otherwise consider blob_parse_untrusted */
+int
+blob_parse(struct blob_attr *attr, struct blob_attr **data, const struct blob_attr_info *info, int max)
+{
+       struct blob_attr *pos;
+       int found = 0;
+       size_t rem;
+
+       memset(data, 0, sizeof(struct blob_attr *) * max);
+       blob_for_each_attr(pos, attr, rem) {
+               found += blob_parse_attr(pos, rem, data, info, max);
+       }
+
        return found;
 }