blobmsg: drop old comment about json formatting functions

[oweals/libubox.git] / blob.c

diff --git a/blob.c b/blob.c
index 10c1f49e4aa1330df04a326d7033a70493ea22e9..433becb904f54d4e0b3fb186756f62c71beb0ba5 100644 (file)
--- a/blob.c
+++ b/blob.c
@@ -21,12 +21,15 @@
 static bool
 blob_buffer_grow(struct blob_buf *buf, int minlen)
 {
+       struct blob_buf *new;
        int delta = ((minlen / 256) + 1) * 256;
-       buf->buflen += delta;
-       buf->buf = realloc(buf->buf, buf->buflen);
-       if (buf->buf)
-               memset(buf->buf + buf->buflen - delta, 0, delta);
-       return !!buf->buf;
+       new = realloc(buf->buf, buf->buflen + delta);
+       if (new) {
+               buf->buf = new;
+               memset(buf->buf + buf->buflen, 0, delta);
+               buf->buflen += delta;
+       }
+       return !!new;
 }
 
 static void
@@ -50,15 +53,16 @@ attr_to_offset(struct blob_buf *buf, struct blob_attr *attr)
        return (char *)attr - (char *) buf->buf + BLOB_COOKIE;
 }
 
-void
+bool
 blob_buf_grow(struct blob_buf *buf, int required)
 {
        int offset_head = attr_to_offset(buf, buf->head);
 
        if (!buf->grow || !buf->grow(buf, required))
-               return;
+               return false;
 
        buf->head = offset_to_attr(buf, offset_head);
+       return true;
 }
 
 static struct blob_attr *
@@ -69,7 +73,8 @@ blob_add(struct blob_buf *buf, struct blob_attr *pos, int id, int payload)
        struct blob_attr *attr;
 
        if (required > 0) {
-               blob_buf_grow(buf, required);
+               if (!blob_buf_grow(buf, required))
+                       return NULL;
                attr = offset_to_attr(buf, offset);
        } else {
                attr = pos;
@@ -142,6 +147,8 @@ blob_put_raw(struct blob_buf *buf, const void *ptr, unsigned int len)
                return NULL;
 
        attr = blob_add(buf, blob_next(buf->head), 0, len - sizeof(struct blob_attr));
+       if (!attr)
+               return NULL;
        blob_set_raw_len(buf->head, blob_pad_len(buf->head) + len);
        memcpy(attr, ptr, len);
        return attr;
@@ -166,6 +173,8 @@ blob_nest_start(struct blob_buf *buf, int id)
 {
        unsigned long offset = attr_to_offset(buf, buf->head);
        buf->head = blob_new(buf, id, 0);
+       if (!buf->head)
+               return NULL;
        return (void *) offset;
 }
 
@@ -177,12 +186,13 @@ 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),
        [BLOB_ATTR_INT32] = sizeof(uint32_t),
        [BLOB_ATTR_INT64] = sizeof(uint64_t),
+       [BLOB_ATTR_DOUBLE] = sizeof(double),
 };
 
 bool
@@ -207,44 +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 (id >= max)
-                       continue;
+       if (!attr || attr_len < sizeof(struct blob_attr))
+               return 0;
 
-               if (info) {
-                       int type = info[id].type;
+       id = blob_id(attr);
+       if (id >= max)
+               return 0;
 
-                       if (type < BLOB_ATTR_LAST) {
-                               if (!blob_check_type(blob_data(pos), len, type))
-                                       continue;
-                       }
+       len = blob_raw_len(attr);
+       if (len > attr_len || len < sizeof(struct blob_attr))
+               return 0;
 
-                       if (info[id].minlen && len < info[id].minlen)
-                               continue;
+       data_len = blob_len(attr);
+       if (data_len > len)
+               return 0;
 
-                       if (info[id].maxlen && len > info[id].maxlen)
-                               continue;
+       if (info) {
+               int type = info[id].type;
 
-                       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;
 
-               data[id] = pos;
+               if (info[id].maxlen && len > info[id].maxlen)
+                       return 0;
+
+               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;
 }