1# SPDX-License-Identifier: BSD-3-Clause 2# Copyright(c) 2023-2024 University of New Hampshire 3 4"""Multi-segment packet scattering testing suite. 5 6This testing suite tests the support of transmitting and receiving scattered packets. 7This is shown by the Poll Mode Driver being able to forward 8scattered multi-segment packets composed of multiple non-contiguous memory buffers. 9To ensure the receipt of scattered packets, 10the DMA rings of the port's Rx queues must be configured 11with mbuf data buffers whose size is less than the maximum length. 12 13If it is the case that the Poll Mode Driver can forward scattered packets which it receives, 14then this suffices to show the Poll Mode Driver is capable of both receiving and transmitting 15scattered packets. 16""" 17 18import struct 19 20from scapy.layers.inet import IP # type: ignore[import-untyped] 21from scapy.layers.l2 import Ether # type: ignore[import-untyped] 22from scapy.packet import Raw # type: ignore[import-untyped] 23from scapy.utils import hexstr # type: ignore[import-untyped] 24 25from framework.params.testpmd import SimpleForwardingModes 26from framework.remote_session.testpmd_shell import TestPmdShell 27from framework.test_suite import TestSuite 28 29 30class TestPmdBufferScatter(TestSuite): 31 """DPDK PMD packet scattering test suite. 32 33 Configure the Rx queues to have mbuf data buffers 34 whose sizes are smaller than the maximum packet size. 35 Specifically, set mbuf data buffers to have a size of 2048 36 to fit a full 1512-byte (CRC included) ethernet frame in a mono-segment packet. 37 The testing of scattered packets is done by sending a packet 38 whose length is greater than the size of the configured size of mbuf data buffers. 39 There are a total of 5 packets sent within test cases 40 which have lengths less than, equal to, and greater than the mbuf size. 41 There are multiple packets sent with lengths greater than the mbuf size 42 in order to test cases such as: 43 44 1. A single byte of the CRC being in a second buffer 45 while the remaining 3 bytes are stored in the first buffer alongside packet data. 46 2. The entire CRC being stored in a second buffer 47 while all of the packet data is stored in the first. 48 3. Most of the packet data being stored in the first buffer 49 and a single byte of packet data stored in a second buffer alongside the CRC. 50 """ 51 52 def set_up_suite(self) -> None: 53 """Set up the test suite. 54 55 Setup: 56 Verify that we have at least 2 port links in the current test run 57 and increase the MTU of both ports on the traffic generator to 9000 58 to support larger packet sizes. 59 """ 60 self.verify( 61 len(self._port_links) > 1, 62 "There must be at least two port links to run the scatter test suite", 63 ) 64 65 self.tg_node.main_session.configure_port_mtu(9000, self._tg_port_egress) 66 self.tg_node.main_session.configure_port_mtu(9000, self._tg_port_ingress) 67 68 def scatter_pktgen_send_packet(self, pktsize: int) -> str: 69 """Generate and send a packet to the SUT then capture what is forwarded back. 70 71 Generate an IP packet of a specific length and send it to the SUT, 72 then capture the resulting received packet and extract its payload. 73 The desired length of the packet is met by packing its payload 74 with the letter "X" in hexadecimal. 75 76 Args: 77 pktsize: Size of the packet to generate and send. 78 79 Returns: 80 The payload of the received packet as a string. 81 """ 82 packet = Ether() / IP() / Raw() 83 packet.getlayer(2).load = "" 84 payload_len = pktsize - len(packet) - 4 85 payload = ["58"] * payload_len 86 # pack the payload 87 for X_in_hex in payload: 88 packet.load += struct.pack("=B", int("%s%s" % (X_in_hex[0], X_in_hex[1]), 16)) 89 received_packets = self.send_packet_and_capture(packet) 90 self.verify(len(received_packets) > 0, "Did not receive any packets.") 91 load = hexstr(received_packets[0].getlayer(2), onlyhex=1) 92 93 return load 94 95 def pmd_scatter(self, mbsize: int) -> None: 96 """Testpmd support of receiving and sending scattered multi-segment packets. 97 98 Support for scattered packets is shown by sending 5 packets of differing length 99 where the length of the packet is calculated by taking mbuf-size + an offset. 100 The offsets used in the test are -1, 0, 1, 4, 5 respectively. 101 102 Test: 103 Start testpmd and run functional test with preset mbsize. 104 """ 105 with TestPmdShell( 106 self.sut_node, 107 forward_mode=SimpleForwardingModes.mac, 108 mbcache=200, 109 mbuf_size=[mbsize], 110 max_pkt_len=9000, 111 tx_offloads=0x00008000, 112 ) as testpmd: 113 testpmd.start() 114 115 for offset in [-1, 0, 1, 4, 5]: 116 recv_payload = self.scatter_pktgen_send_packet(mbsize + offset) 117 self._logger.debug( 118 f"Payload of scattered packet after forwarding: \n{recv_payload}" 119 ) 120 self.verify( 121 ("58 " * 8).strip() in recv_payload, 122 "Payload of scattered packet did not match expected payload with offset " 123 f"{offset}.", 124 ) 125 126 def test_scatter_mbuf_2048(self) -> None: 127 """Run the :meth:`pmd_scatter` test with `mbsize` set to 2048.""" 128 self.pmd_scatter(mbsize=2048) 129 130 def tear_down_suite(self) -> None: 131 """Tear down the test suite. 132 133 Teardown: 134 Set the MTU of the tg_node back to a more standard size of 1500. 135 """ 136 self.tg_node.main_session.configure_port_mtu(1500, self._tg_port_egress) 137 self.tg_node.main_session.configure_port_mtu(1500, self._tg_port_ingress) 138