src/fuzz/fuzz-dns-packet.c

   1 /* SPDX-License-Identifier: LGPL-2.1-or-later */
   2
   3 #include "fuzz.h"
   4 #include "memory-util.h"
   5 #include "resolved-dns-packet.h"
   6
   7 int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
   8         _cleanup_(dns_packet_unrefp) DnsPacket *p = NULL;
   9
  10         if (size > DNS_PACKET_SIZE_MAX)
  11                 return 0;
  12
  13         assert_se(dns_packet_new(&p, DNS_PROTOCOL_DNS, 0, DNS_PACKET_SIZE_MAX) >= 0);
  14         p->size = 0; /* by default append starts after the header, undo that */
  15         assert_se(dns_packet_append_blob(p, data, size, NULL) >= 0);
  16         if (size < DNS_PACKET_HEADER_SIZE) {
  17                 /* make sure we pad the packet back up to the minimum header size */
  18                 assert_se(p->allocated >= DNS_PACKET_HEADER_SIZE);
  19                 memzero(DNS_PACKET_DATA(p) + size, DNS_PACKET_HEADER_SIZE - size);
  20                 p->size = DNS_PACKET_HEADER_SIZE;
  21         }
  22         (void) dns_packet_extract(p);
  23
  24         return 0;
  25 }