simple_dns

Module header_buffer

source
Expand description

Helper functions to assert a buffer for the header flags of a DNS Packet. Useful for checking the header without parsing the whole packet.
WARNING: Flags and RCODE information may be incomplete if the packet contains EDNS (OPT) or DNSSEC Resource Records

use simple_dns::{header_buffer, PacketFlag};

let buffer = b"\xff\xff\x03\x00\x00\x02\x00\x02\x00\x02\x00\x02";
assert_eq!(u16::MAX, header_buffer::id(&buffer[..]).unwrap());
assert!(!header_buffer::has_flags(&buffer[..], PacketFlag::RESPONSE).unwrap());

Functionsยง

  • additional_records
    Returns the additional records from the header buffer
  • answers
    Returns the answers count from the header buffer
  • has_flags
    Verify if buffer has the flags set.
    WARNING: This information may be wrong if there is an OPT record in packet
  • id
    Returns the packet id from the header buffer
  • name_servers
    Returns the name servers count from the header buffer
  • opcode
    Get the OPCODE from the buffer
  • questions
    Returns the questions count from the header buffer
  • rcode
    Get the RCODE from the buffer.
    WARNING: This information may be wrong if there is an OPT record in packet