Class DNSPacketConstructor

Class Documentation

class DNSPacketConstructor

Class that contains methods to construct Ipv4/Ipv6 DNS packets Constructs the Ethernet, Ip, Udp, and DNS headers.

Public Static Functions

static inline size_t ConstructIpv4DNSPacket(RTEMbuf<DefaultPacket> &pkt, const rte_ether_addr &src_mac_addr, const rte_ether_addr &dst_mac_addr, const uint32_t src_ipv4_addr, const uint32_t dst_ipv4_addr, uint16_t src_port, uint16_t dns_id, const char *domain_name, const uint16_t len, DnsQType q_type)

Constructs a Ipv4 DNS packet in pkt.

Constructs the Ethernet, Ip, Udp, and DNS headers Checksums are not calculated

Parameters:

  • pkt – Pointer to the MBuf to fill

  • src_mac_addr – Source MAC address

  • dst_mac_addr – Destination MAC address

  • src_ipv4_addr – Source Ipv4 address

  • dst_ipv4_addr – Destination Ipv4 address

  • src_port – Source port must be highter than 49152, destination port is always 53

  • dns_id – 16 bits DNS ID

  • domain_name – Pointer to buffer with domain name, can have trailing dot

  • len – Length of domain_name

  • q_type – Question type to ask the resolver

Returns:

size_t

static inline size_t ConstructIpv6DNSPacket(RTEMbuf<DefaultPacket> &pkt, const rte_ether_addr &src_mac_addr, const rte_ether_addr &dst_mac_addr, const in6_addr &src_ipv6_addr, const in6_addr &dst_ipv6_addr, uint16_t src_port, uint16_t dns_id, const char *domain_name, const uint16_t len, DnsQType q_type)

Constructs a Ipv6 DNS packet in pkt.

Constructs the Ethernet, Ip, Udp, and DNS headers Checksums are not calculated

Parameters:

  • pkt –

  • src_mac_addr –

  • dst_mac_addr –

  • src_ipv6_addr –

  • dst_ipv6_addr –

  • src_port –

  • dns_id –

  • domain_name –

  • len –

  • q_type –

Returns:

size_t

static inline size_t GetMinIpv4PacketSize()

Get the minimum size of a Ipv4 DNS packet, size is counted from the ethernet header To get the total size of a DNS packet the domain name length with trailing dot should be added to this packet size.

Returns:

size_t length

static inline size_t GetMinIpv6PacketSize()

Get the minimum size of a Ipv6 DNS packet, size is counted from the ethernet header To get the total size of a DNS packet the domain name length with trailing dot should be added to this packet size.

Returns:

size_t length