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, func_test 28from framework.testbed_model.capability import NicCapability, requires 29 30 31class TestPmdBufferScatter(TestSuite): 32 """DPDK PMD packet scattering test suite. 33 34 Configure the Rx queues to have mbuf data buffers 35 whose sizes are smaller than the maximum packet size. 36 Specifically, set mbuf data buffers to have a size of 2048 37 to fit a full 1512-byte (CRC included) ethernet frame in a mono-segment packet. 38 The testing of scattered packets is done by sending a packet 39 whose length is greater than the size of the configured size of mbuf data buffers. 40 There are a total of 5 packets sent within test cases 41 which have lengths less than, equal to, and greater than the mbuf size. 42 There are multiple packets sent with lengths greater than the mbuf size 43 in order to test cases such as: 44 45 1. A single byte of the CRC being in a second buffer 46 while the remaining 3 bytes are stored in the first buffer alongside packet data. 47 2. The entire CRC being stored in a second buffer 48 while all of the packet data is stored in the first. 49 3. Most of the packet data being stored in the first buffer 50 and a single byte of packet data stored in a second buffer alongside the CRC. 51 """ 52 53 def set_up_suite(self) -> None: 54 """Set up the test suite. 55 56 Setup: 57 Increase the MTU of both ports on the traffic generator to 9000 58 to support larger packet sizes. 59 """ 60 self.tg_node.main_session.configure_port_mtu(9000, self._tg_port_egress) 61 self.tg_node.main_session.configure_port_mtu(9000, self._tg_port_ingress) 62 63 def scatter_pktgen_send_packet(self, pktsize: int) -> str: 64 """Generate and send a packet to the SUT then capture what is forwarded back. 65 66 Generate an IP packet of a specific length and send it to the SUT, 67 then capture the resulting received packet and extract its payload. 68 The desired length of the packet is met by packing its payload 69 with the letter "X" in hexadecimal. 70 71 Args: 72 pktsize: Size of the packet to generate and send. 73 74 Returns: 75 The payload of the received packet as a string. 76 """ 77 packet = Ether() / IP() / Raw() 78 packet.getlayer(2).load = "" 79 payload_len = pktsize - len(packet) - 4 80 payload = ["58"] * payload_len 81 # pack the payload 82 for X_in_hex in payload: 83 packet.load += struct.pack("=B", int("%s%s" % (X_in_hex[0], X_in_hex[1]), 16)) 84 received_packets = self.send_packet_and_capture(packet) 85 self.verify(len(received_packets) > 0, "Did not receive any packets.") 86 load = hexstr(received_packets[0].getlayer(2), onlyhex=1) 87 88 return load 89 90 def pmd_scatter(self, mbsize: int) -> None: 91 """Testpmd support of receiving and sending scattered multi-segment packets. 92 93 Support for scattered packets is shown by sending 5 packets of differing length 94 where the length of the packet is calculated by taking mbuf-size + an offset. 95 The offsets used in the test are -1, 0, 1, 4, 5 respectively. 96 97 Test: 98 Start testpmd and run functional test with preset mbsize. 99 """ 100 with TestPmdShell( 101 self.sut_node, 102 forward_mode=SimpleForwardingModes.mac, 103 mbcache=200, 104 mbuf_size=[mbsize], 105 max_pkt_len=9000, 106 tx_offloads=0x00008000, 107 ) as testpmd: 108 testpmd.start() 109 110 for offset in [-1, 0, 1, 4, 5]: 111 recv_payload = self.scatter_pktgen_send_packet(mbsize + offset) 112 self._logger.debug( 113 f"Payload of scattered packet after forwarding: \n{recv_payload}" 114 ) 115 self.verify( 116 ("58 " * 8).strip() in recv_payload, 117 "Payload of scattered packet did not match expected payload with offset " 118 f"{offset}.", 119 ) 120 121 @requires(NicCapability.SCATTERED_RX_ENABLED) 122 @func_test 123 def test_scatter_mbuf_2048(self) -> None: 124 """Run the :meth:`pmd_scatter` test with `mbsize` set to 2048.""" 125 self.pmd_scatter(mbsize=2048) 126 127 def tear_down_suite(self) -> None: 128 """Tear down the test suite. 129 130 Teardown: 131 Set the MTU of the tg_node back to a more standard size of 1500. 132 """ 133 self.tg_node.main_session.configure_port_mtu(1500, self._tg_port_egress) 134 self.tg_node.main_session.configure_port_mtu(1500, self._tg_port_ingress) 135