Allow string/octet "arrays" with length=uint8 (#4415)

This is the DHCPv4 analog of 64ea2f5, the analogous DHCPv6 change.

diff --git a/src/protocols/dhcpv4/base.c b/src/protocols/dhcpv4/base.c
index 71dfc3b237da8b78f82d317784865769814e8c89..e9f0ac703d2551bb329f5510ef099222941424ba 100644 (file)
--- a/src/protocols/dhcpv4/base.c
+++ b/src/protocols/dhcpv4/base.c
@@ -659,7 +659,18 @@ static fr_table_num_ordered_t const subtype_table[] = {
 static bool attr_valid(UNUSED fr_dict_t *dict, UNUSED fr_dict_attr_t const *parent,
                       UNUSED char const *name, UNUSED int attr, fr_type_t type, fr_dict_attr_flags_t *flags)
 {
-       if (flags->array && !flags->length) {
+       /*
+        *      "arrays" of string/octets are encoded as a 8-bit
+        *      length, followed by the actual data.
+        */
+       if (flags->array && ((type == FR_TYPE_STRING) || (type == FR_TYPE_OCTETS))) {
+               flags->is_known_width = true;
+
+               if (flags->extra && (flags->subtype != FLAG_LENGTH_UINT8)) {
+                       fr_strerror_const("string/octets arrays require the 'length=uint8' flag");
+                       return false;
+               }
+       } else if (flags->array && !flags->length) {
                fr_strerror_const("Variable length attributes cannot be marked as 'array'");
                return false;
        }