PacketCtor.cpp

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#include <rte_ethdev.h>
 
#include "dpdklibs/ipv4_addr.hpp"
#include "dpdklibs/udp/PacketCtor.hpp"
#include "dpdklibs/udp/Utils.hpp"
 
#include "detdataformats/DAQEthHeader.hpp"
 
#define IPV4_VERSION 4
 
// DEFAULT_TTL             = 8 -> TTL on wireshark 5
// DEFAULT_TTL             = 5 -> TTL on wireshark 2
// DEFAULT_TTL             = 4 -> TTL on wireshark 1
 
namespace dunedaq {
namespace dpdklibs {
namespace udp {
 
enum
{
  MIN_TOS = 0,
  DEFAULT_TOS = MIN_TOS,
  DEFAULT_TTL = 8
};
static int8_t
get_xdigit(char ch)
{
  if (ch >= '0' && ch <= '9')
    return ch - '0';
  if (ch >= 'a' && ch <= 'f')
    return ch - 'a' + 10;
  if (ch >= 'A' && ch <= 'F')
    return ch - 'A' + 10;
  return -1;
}
 
bool
get_ether_addr6(const char* s0, struct rte_ether_addr* ea)
{
  const char* s = s0;
  int i;
 
  for (i = 0; i < RTE_ETHER_ADDR_LEN; i++) {
    int8_t x;
 
    x = get_xdigit(*s++);
    if (x < 0)
      return false;
 
    ea->addr_bytes[i] = x << 4;
    x = get_xdigit(*s++);
    if (x < 0)
      return false;
    ea->addr_bytes[i] |= x;
 
    if (i < RTE_ETHER_ADDR_LEN - 1 && *s++ != ':')
      return false;
  }
 
  /* return true if at end of string */
  return *s == '\0';
}
 
rte_le16_t
packet_fill(struct ipv4_udp_packet_hdr* packet_hdr)
{
  // rte_le16_t total_length = 64;
  // char message[] = "AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA";
 
  rte_le16_t total_length = 2000;
  char message[] =
    "EEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEE"
    "EEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEE"
    "EEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEE"
    "EEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEE"
    "EEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEE"
    "EEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEE"
    "EEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEE"
    "EEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEE"
    "EEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEE"
    "EEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEE"
    "EEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEE"
    "EEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEE"
    "EEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEE"
    "EEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEE"
    "EEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEE"
    "EEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEE"
    "EEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEE"
    "EEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEE";
 
  char* payload = (char*)(packet_hdr + 1);
  memcpy(payload, message, total_length);
  return total_length;
}
 
/**************************************************************************/ 
void
pktgen_udp_hdr_ctor(struct ipv4_udp_packet_hdr* packet_hdr, rte_le16_t packet_len, int sport, int dport)
{
  packet_hdr->udp_hdr.dgram_len = rte_cpu_to_be_16(packet_len);
 
  packet_hdr->udp_hdr.src_port = rte_cpu_to_be_16(sport);
  packet_hdr->udp_hdr.dst_port = rte_cpu_to_be_16(dport);
 
  packet_hdr->udp_hdr.dgram_cksum = 0; // checksum must be set to 0 in the L4 header by the caller.
  // TODO  I think that the payload must be already there and continuous in memory..
  return;
}
 
/**************************************************************************/ 
void
pktgen_ipv4_ctor(struct ipv4_udp_packet_hdr* packet_hdr,
                 rte_le16_t packet_len,
                 const std::string& src_ip_addr,
                 const std::string& dst_ip_addr)
{
  /* IPv4 Header constructor */
 
  /* Zero out the header space */
  memset((char*)&packet_hdr->ipv4_hdr, 0, sizeof(struct rte_ipv4_hdr));
 
  IpAddr src(src_ip_addr);
  IpAddr dst(dst_ip_addr);
 
  struct ipaddr src_reversed_order;
  src_reversed_order.addr_bytes[3] = src.addr_bytes[0];
  src_reversed_order.addr_bytes[2] = src.addr_bytes[1];
  src_reversed_order.addr_bytes[1] = src.addr_bytes[2];
  src_reversed_order.addr_bytes[0] = src.addr_bytes[3];
 
  struct ipaddr dst_reversed_order;
  dst_reversed_order.addr_bytes[3] = dst.addr_bytes[0];
  dst_reversed_order.addr_bytes[2] = dst.addr_bytes[1];
  dst_reversed_order.addr_bytes[1] = dst.addr_bytes[2];
  dst_reversed_order.addr_bytes[0] = dst.addr_bytes[3];
 
  rte_le32_t src_addr_ser = *((rte_le32_t*)&src_reversed_order);
  rte_le32_t dst_addr_ser = *((rte_le32_t*)&dst_reversed_order);
 
  packet_hdr->ipv4_hdr.src_addr = rte_cpu_to_be_32(src_addr_ser);
  packet_hdr->ipv4_hdr.dst_addr = rte_cpu_to_be_32(dst_addr_ser);
 
  packet_hdr->ipv4_hdr.version_ihl = (IPV4_VERSION << 4) | (sizeof(struct rte_ipv4_hdr) / 4);
 
  packet_hdr->ipv4_hdr.total_length = rte_cpu_to_be_16(packet_len); // Payload + udp_hdr + iphdr
  packet_hdr->ipv4_hdr.time_to_live = DEFAULT_TTL;
  packet_hdr->ipv4_hdr.type_of_service = DEFAULT_TOS;
 
  // https://perso.telecom-paristech.fr/drossi/paper/rossi17ipid.pdf
  packet_hdr->ipv4_hdr.packet_id = rte_cpu_to_be_16(0); // I put a constant here..
  packet_hdr->ipv4_hdr.fragment_offset = 0;
  packet_hdr->ipv4_hdr.next_proto_id = IPPROTO_UDP;
 
  packet_hdr->ipv4_hdr.hdr_checksum = 0;
  // packet_hdr->ipv4_hdr.hdr_checksum = rte_ipv4_cksum(&packet_hdr->ipv4_hdr);
 
  // UDP checksum
  packet_hdr->udp_hdr.dgram_cksum = 0;
  // packet_hdr->udp_hdr.dgram_cksum = rte_ipv4_udptcp_cksum(&packet_hdr->ipv4_hdr, (void *) &packet_hdr->udp_hdr);
  // if (packet_hdr->udp_hdr.dgram_cksum == 0) {
  //     packet_hdr->udp_hdr.dgram_cksum = 0xFFFF;
  // }
  return;
}
 
/**************************************************************************/ 
void
pktgen_ether_hdr_ctor(struct ipv4_udp_packet_hdr* packet_hdr, const std::string& router_mac_address, const int port_id)
{
  // pg_ether_addr_copy(&pkt->eth_src_addr, &eth->src_addr);
  // pg_ether_addr_copy(&pkt->eth_dst_addr, &eth->dst_addr);
 
  /* src and dest addr */
  // See definition dpdk-20.08/lib/librte_net/rte_ether.c is defined as static -> not exposed to the lib... redefining
  // here
 
  get_ether_addr6(router_mac_address.c_str(), &packet_hdr->eth_hdr.dst_addr);
 
  rte_eth_macaddr_get(port_id, &packet_hdr->eth_hdr.src_addr);
 
  /* normal ethernet header */
  packet_hdr->eth_hdr.ether_type = rte_cpu_to_be_16(RTE_ETHER_TYPE_IPV4);
  return;
}
 
void
construct_packets_for_burst(const int port_id,
                            const std::string& dst_mac_addr,
                            const int payload_bytes,
                            const int burst_size,
                            rte_mbuf** bufs)
{
  struct ipv4_udp_packet_hdr packet_hdr;
 
  constexpr int eth_header_bytes = 14;
  constexpr int udp_header_bytes = 8;
  constexpr int ipv4_header_bytes = 20;
 
  int eth_packet_bytes =
    eth_header_bytes + ipv4_header_bytes + udp_header_bytes + sizeof(detdataformats::DAQEthHeader) + payload_bytes;
  int ipv4_packet_bytes = eth_packet_bytes - eth_header_bytes;
  int udp_datagram_bytes = ipv4_packet_bytes - ipv4_header_bytes;
 
  // Get info for the ethernet header (protocol stack level 2)
  pktgen_ether_hdr_ctor(&packet_hdr, dst_mac_addr, port_id);
 
  // Get info for the internet header (protocol stack level 3)
  pktgen_ipv4_ctor(&packet_hdr, ipv4_packet_bytes);
 
  // Get info for the UDP header (protocol stack level 4)
  pktgen_udp_hdr_ctor(&packet_hdr, udp_datagram_bytes);
 
  detdataformats::DAQEthHeader daqethheader_obj;
  set_daqethheader_test_values(daqethheader_obj);
 
  void* dataloc = nullptr;
  for (int i_pkt = 0; i_pkt < burst_size; ++i_pkt) {
 
    dataloc = rte_pktmbuf_mtod(bufs[i_pkt], char*);
    rte_memcpy(dataloc, &packet_hdr, sizeof(packet_hdr));
 
    dataloc = rte_pktmbuf_mtod_offset(bufs[i_pkt], char*, sizeof(packet_hdr));
    rte_memcpy(dataloc, &daqethheader_obj, sizeof(daqethheader_obj));
 
    bufs[i_pkt]->pkt_len = eth_packet_bytes;
    bufs[i_pkt]->data_len = eth_packet_bytes;
  }
}
 
} // namespace udp
} // namespace dpdklibs
} // namespace dunedaq