From 6aab1c81b98a90a9289a4d5256b6f7374872cc3f Mon Sep 17 00:00:00 2001 From: Jussi Maki Date: Sat, 31 Jul 2021 05:57:38 +0000 Subject: [PATCH] selftests/bpf: Add tests for XDP bonding Add a test suite to test XDP bonding implementation over a pair of veth devices. Signed-off-by: Jussi Maki Signed-off-by: Daniel Borkmann Acked-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/20210731055738.16820-8-joamaki@gmail.com --- .../testing/selftests/bpf/prog_tests/xdp_bonding.c | 520 +++++++++++++++++++++ 1 file changed, 520 insertions(+) create mode 100644 tools/testing/selftests/bpf/prog_tests/xdp_bonding.c diff --git a/tools/testing/selftests/bpf/prog_tests/xdp_bonding.c b/tools/testing/selftests/bpf/prog_tests/xdp_bonding.c new file mode 100644 index 000000000000..6b186b4238d0 --- /dev/null +++ b/tools/testing/selftests/bpf/prog_tests/xdp_bonding.c @@ -0,0 +1,520 @@ +// SPDX-License-Identifier: GPL-2.0 + +/** + * Test XDP bonding support + * + * Sets up two bonded veth pairs between two fresh namespaces + * and verifies that XDP_TX program loaded on a bond device + * are correctly loaded onto the slave devices and XDP_TX'd + * packets are balanced using bonding. + */ + +#define _GNU_SOURCE +#include +#include +#include +#include "test_progs.h" +#include "network_helpers.h" +#include +#include +#include + +#include "xdp_dummy.skel.h" +#include "xdp_redirect_multi_kern.skel.h" +#include "xdp_tx.skel.h" + +#define BOND1_MAC {0x00, 0x11, 0x22, 0x33, 0x44, 0x55} +#define BOND1_MAC_STR "00:11:22:33:44:55" +#define BOND2_MAC {0x00, 0x22, 0x33, 0x44, 0x55, 0x66} +#define BOND2_MAC_STR "00:22:33:44:55:66" +#define NPACKETS 100 + +static int root_netns_fd = -1; + +static void restore_root_netns(void) +{ + ASSERT_OK(setns(root_netns_fd, CLONE_NEWNET), "restore_root_netns"); +} + +static int setns_by_name(char *name) +{ + int nsfd, err; + char nspath[PATH_MAX]; + + snprintf(nspath, sizeof(nspath), "%s/%s", "/var/run/netns", name); + nsfd = open(nspath, O_RDONLY | O_CLOEXEC); + if (nsfd < 0) + return -1; + + err = setns(nsfd, CLONE_NEWNET); + close(nsfd); + return err; +} + +static int get_rx_packets(const char *iface) +{ + FILE *f; + char line[512]; + int iface_len = strlen(iface); + + f = fopen("/proc/net/dev", "r"); + if (!f) + return -1; + + while (fgets(line, sizeof(line), f)) { + char *p = line; + + while (*p == ' ') + p++; /* skip whitespace */ + if (!strncmp(p, iface, iface_len)) { + p += iface_len; + if (*p++ != ':') + continue; + while (*p == ' ') + p++; /* skip whitespace */ + while (*p && *p != ' ') + p++; /* skip rx bytes */ + while (*p == ' ') + p++; /* skip whitespace */ + fclose(f); + return atoi(p); + } + } + fclose(f); + return -1; +} + +#define MAX_BPF_LINKS 8 + +struct skeletons { + struct xdp_dummy *xdp_dummy; + struct xdp_tx *xdp_tx; + struct xdp_redirect_multi_kern *xdp_redirect_multi_kern; + + int nlinks; + struct bpf_link *links[MAX_BPF_LINKS]; +}; + +static int xdp_attach(struct skeletons *skeletons, struct bpf_program *prog, char *iface) +{ + struct bpf_link *link; + int ifindex; + + ifindex = if_nametoindex(iface); + if (!ASSERT_GT(ifindex, 0, "get ifindex")) + return -1; + + if (!ASSERT_LE(skeletons->nlinks+1, MAX_BPF_LINKS, "too many XDP programs attached")) + return -1; + + link = bpf_program__attach_xdp(prog, ifindex); + if (!ASSERT_OK_PTR(link, "attach xdp program")) + return -1; + + skeletons->links[skeletons->nlinks++] = link; + return 0; +} + +enum { + BOND_ONE_NO_ATTACH = 0, + BOND_BOTH_AND_ATTACH, +}; + +static const char * const mode_names[] = { + [BOND_MODE_ROUNDROBIN] = "balance-rr", + [BOND_MODE_ACTIVEBACKUP] = "active-backup", + [BOND_MODE_XOR] = "balance-xor", + [BOND_MODE_BROADCAST] = "broadcast", + [BOND_MODE_8023AD] = "802.3ad", + [BOND_MODE_TLB] = "balance-tlb", + [BOND_MODE_ALB] = "balance-alb", +}; + +static const char * const xmit_policy_names[] = { + [BOND_XMIT_POLICY_LAYER2] = "layer2", + [BOND_XMIT_POLICY_LAYER34] = "layer3+4", + [BOND_XMIT_POLICY_LAYER23] = "layer2+3", + [BOND_XMIT_POLICY_ENCAP23] = "encap2+3", + [BOND_XMIT_POLICY_ENCAP34] = "encap3+4", +}; + +static int bonding_setup(struct skeletons *skeletons, int mode, int xmit_policy, + int bond_both_attach) +{ +#define SYS(fmt, ...) \ + ({ \ + char cmd[1024]; \ + snprintf(cmd, sizeof(cmd), fmt, ##__VA_ARGS__); \ + if (!ASSERT_OK(system(cmd), cmd)) \ + return -1; \ + }) + + SYS("ip netns add ns_dst"); + SYS("ip link add veth1_1 type veth peer name veth2_1 netns ns_dst"); + SYS("ip link add veth1_2 type veth peer name veth2_2 netns ns_dst"); + + SYS("ip link add bond1 type bond mode %s xmit_hash_policy %s", + mode_names[mode], xmit_policy_names[xmit_policy]); + SYS("ip link set bond1 up address " BOND1_MAC_STR " addrgenmode none"); + SYS("ip -netns ns_dst link add bond2 type bond mode %s xmit_hash_policy %s", + mode_names[mode], xmit_policy_names[xmit_policy]); + SYS("ip -netns ns_dst link set bond2 up address " BOND2_MAC_STR " addrgenmode none"); + + SYS("ip link set veth1_1 master bond1"); + if (bond_both_attach == BOND_BOTH_AND_ATTACH) { + SYS("ip link set veth1_2 master bond1"); + } else { + SYS("ip link set veth1_2 up addrgenmode none"); + + if (xdp_attach(skeletons, skeletons->xdp_dummy->progs.xdp_dummy_prog, "veth1_2")) + return -1; + } + + SYS("ip -netns ns_dst link set veth2_1 master bond2"); + + if (bond_both_attach == BOND_BOTH_AND_ATTACH) + SYS("ip -netns ns_dst link set veth2_2 master bond2"); + else + SYS("ip -netns ns_dst link set veth2_2 up addrgenmode none"); + + /* Load a dummy program on sending side as with veth peer needs to have a + * XDP program loaded as well. + */ + if (xdp_attach(skeletons, skeletons->xdp_dummy->progs.xdp_dummy_prog, "bond1")) + return -1; + + if (bond_both_attach == BOND_BOTH_AND_ATTACH) { + if (!ASSERT_OK(setns_by_name("ns_dst"), "set netns to ns_dst")) + return -1; + + if (xdp_attach(skeletons, skeletons->xdp_tx->progs.xdp_tx, "bond2")) + return -1; + + restore_root_netns(); + } + + return 0; + +#undef SYS +} + +static void bonding_cleanup(struct skeletons *skeletons) +{ + restore_root_netns(); + while (skeletons->nlinks) { + skeletons->nlinks--; + bpf_link__destroy(skeletons->links[skeletons->nlinks]); + } + ASSERT_OK(system("ip link delete bond1"), "delete bond1"); + ASSERT_OK(system("ip link delete veth1_1"), "delete veth1_1"); + ASSERT_OK(system("ip link delete veth1_2"), "delete veth1_2"); + ASSERT_OK(system("ip netns delete ns_dst"), "delete ns_dst"); +} + +static int send_udp_packets(int vary_dst_ip) +{ + struct ethhdr eh = { + .h_source = BOND1_MAC, + .h_dest = BOND2_MAC, + .h_proto = htons(ETH_P_IP), + }; + uint8_t buf[128] = {}; + struct iphdr *iph = (struct iphdr *)(buf + sizeof(eh)); + struct udphdr *uh = (struct udphdr *)(buf + sizeof(eh) + sizeof(*iph)); + int i, s = -1; + int ifindex; + + s = socket(AF_PACKET, SOCK_RAW, IPPROTO_RAW); + if (!ASSERT_GE(s, 0, "socket")) + goto err; + + ifindex = if_nametoindex("bond1"); + if (!ASSERT_GT(ifindex, 0, "get bond1 ifindex")) + goto err; + + memcpy(buf, &eh, sizeof(eh)); + iph->ihl = 5; + iph->version = 4; + iph->tos = 16; + iph->id = 1; + iph->ttl = 64; + iph->protocol = IPPROTO_UDP; + iph->saddr = 1; + iph->daddr = 2; + iph->tot_len = htons(sizeof(buf) - ETH_HLEN); + iph->check = 0; + + for (i = 1; i <= NPACKETS; i++) { + int n; + struct sockaddr_ll saddr_ll = { + .sll_ifindex = ifindex, + .sll_halen = ETH_ALEN, + .sll_addr = BOND2_MAC, + }; + + /* vary the UDP destination port for even distribution with roundrobin/xor modes */ + uh->dest++; + + if (vary_dst_ip) + iph->daddr++; + + n = sendto(s, buf, sizeof(buf), 0, (struct sockaddr *)&saddr_ll, sizeof(saddr_ll)); + if (!ASSERT_EQ(n, sizeof(buf), "sendto")) + goto err; + } + + return 0; + +err: + if (s >= 0) + close(s); + return -1; +} + +static void test_xdp_bonding_with_mode(struct skeletons *skeletons, int mode, int xmit_policy) +{ + int bond1_rx; + + if (bonding_setup(skeletons, mode, xmit_policy, BOND_BOTH_AND_ATTACH)) + goto out; + + if (send_udp_packets(xmit_policy != BOND_XMIT_POLICY_LAYER34)) + goto out; + + bond1_rx = get_rx_packets("bond1"); + ASSERT_EQ(bond1_rx, NPACKETS, "expected more received packets"); + + switch (mode) { + case BOND_MODE_ROUNDROBIN: + case BOND_MODE_XOR: { + int veth1_rx = get_rx_packets("veth1_1"); + int veth2_rx = get_rx_packets("veth1_2"); + int diff = abs(veth1_rx - veth2_rx); + + ASSERT_GE(veth1_rx + veth2_rx, NPACKETS, "expected more packets"); + + switch (xmit_policy) { + case BOND_XMIT_POLICY_LAYER2: + ASSERT_GE(diff, NPACKETS, + "expected packets on only one of the interfaces"); + break; + case BOND_XMIT_POLICY_LAYER23: + case BOND_XMIT_POLICY_LAYER34: + ASSERT_LT(diff, NPACKETS/2, + "expected even distribution of packets"); + break; + default: + PRINT_FAIL("Unimplemented xmit_policy=%d\n", xmit_policy); + break; + } + break; + } + case BOND_MODE_ACTIVEBACKUP: { + int veth1_rx = get_rx_packets("veth1_1"); + int veth2_rx = get_rx_packets("veth1_2"); + int diff = abs(veth1_rx - veth2_rx); + + ASSERT_GE(diff, NPACKETS, + "expected packets on only one of the interfaces"); + break; + } + default: + PRINT_FAIL("Unimplemented xmit_policy=%d\n", xmit_policy); + break; + } + +out: + bonding_cleanup(skeletons); +} + +/* Test the broadcast redirection using xdp_redirect_map_multi_prog and adding + * all the interfaces to it and checking that broadcasting won't send the packet + * to neither the ingress bond device (bond2) or its slave (veth2_1). + */ +static void test_xdp_bonding_redirect_multi(struct skeletons *skeletons) +{ + static const char * const ifaces[] = {"bond2", "veth2_1", "veth2_2"}; + int veth1_1_rx, veth1_2_rx; + int err; + + if (bonding_setup(skeletons, BOND_MODE_ROUNDROBIN, BOND_XMIT_POLICY_LAYER23, + BOND_ONE_NO_ATTACH)) + goto out; + + + if (!ASSERT_OK(setns_by_name("ns_dst"), "could not set netns to ns_dst")) + goto out; + + /* populate the devmap with the relevant interfaces */ + for (int i = 0; i < ARRAY_SIZE(ifaces); i++) { + int ifindex = if_nametoindex(ifaces[i]); + int map_fd = bpf_map__fd(skeletons->xdp_redirect_multi_kern->maps.map_all); + + if (!ASSERT_GT(ifindex, 0, "could not get interface index")) + goto out; + + err = bpf_map_update_elem(map_fd, &ifindex, &ifindex, 0); + if (!ASSERT_OK(err, "add interface to map_all")) + goto out; + } + + if (xdp_attach(skeletons, + skeletons->xdp_redirect_multi_kern->progs.xdp_redirect_map_multi_prog, + "bond2")) + goto out; + + restore_root_netns(); + + if (send_udp_packets(BOND_MODE_ROUNDROBIN)) + goto out; + + veth1_1_rx = get_rx_packets("veth1_1"); + veth1_2_rx = get_rx_packets("veth1_2"); + + ASSERT_EQ(veth1_1_rx, 0, "expected no packets on veth1_1"); + ASSERT_GE(veth1_2_rx, NPACKETS, "expected packets on veth1_2"); + +out: + restore_root_netns(); + bonding_cleanup(skeletons); +} + +/* Test that XDP programs cannot be attached to both the bond master and slaves simultaneously */ +static void test_xdp_bonding_attach(struct skeletons *skeletons) +{ + struct bpf_link *link = NULL; + struct bpf_link *link2 = NULL; + int veth, bond; + int err; + + if (!ASSERT_OK(system("ip link add veth type veth"), "add veth")) + goto out; + if (!ASSERT_OK(system("ip link add bond type bond"), "add bond")) + goto out; + + veth = if_nametoindex("veth"); + if (!ASSERT_GE(veth, 0, "if_nametoindex veth")) + goto out; + bond = if_nametoindex("bond"); + if (!ASSERT_GE(bond, 0, "if_nametoindex bond")) + goto out; + + /* enslaving with a XDP program loaded fails */ + link = bpf_program__attach_xdp(skeletons->xdp_dummy->progs.xdp_dummy_prog, veth); + if (!ASSERT_OK_PTR(link, "attach program to veth")) + goto out; + + err = system("ip link set veth master bond"); + if (!ASSERT_NEQ(err, 0, "attaching slave with xdp program expected to fail")) + goto out; + + bpf_link__destroy(link); + link = NULL; + + err = system("ip link set veth master bond"); + if (!ASSERT_OK(err, "set veth master")) + goto out; + + /* attaching to slave when master has no program is allowed */ + link = bpf_program__attach_xdp(skeletons->xdp_dummy->progs.xdp_dummy_prog, veth); + if (!ASSERT_OK_PTR(link, "attach program to slave when enslaved")) + goto out; + + /* attaching to master not allowed when slave has program loaded */ + link2 = bpf_program__attach_xdp(skeletons->xdp_dummy->progs.xdp_dummy_prog, bond); + if (!ASSERT_ERR_PTR(link2, "attach program to master when slave has program")) + goto out; + + bpf_link__destroy(link); + link = NULL; + + /* attaching XDP program to master allowed when slave has no program */ + link = bpf_program__attach_xdp(skeletons->xdp_dummy->progs.xdp_dummy_prog, bond); + if (!ASSERT_OK_PTR(link, "attach program to master")) + goto out; + + /* attaching to slave not allowed when master has program loaded */ + link2 = bpf_program__attach_xdp(skeletons->xdp_dummy->progs.xdp_dummy_prog, bond); + ASSERT_ERR_PTR(link2, "attach program to slave when master has program"); + +out: + bpf_link__destroy(link); + bpf_link__destroy(link2); + + system("ip link del veth"); + system("ip link del bond"); +} + +static int libbpf_debug_print(enum libbpf_print_level level, + const char *format, va_list args) +{ + if (level != LIBBPF_WARN) + vprintf(format, args); + return 0; +} + +struct bond_test_case { + char *name; + int mode; + int xmit_policy; +}; + +static struct bond_test_case bond_test_cases[] = { + { "xdp_bonding_roundrobin", BOND_MODE_ROUNDROBIN, BOND_XMIT_POLICY_LAYER23, }, + { "xdp_bonding_activebackup", BOND_MODE_ACTIVEBACKUP, BOND_XMIT_POLICY_LAYER23 }, + + { "xdp_bonding_xor_layer2", BOND_MODE_XOR, BOND_XMIT_POLICY_LAYER2, }, + { "xdp_bonding_xor_layer23", BOND_MODE_XOR, BOND_XMIT_POLICY_LAYER23, }, + { "xdp_bonding_xor_layer34", BOND_MODE_XOR, BOND_XMIT_POLICY_LAYER34, }, +}; + +void test_xdp_bonding(void) +{ + libbpf_print_fn_t old_print_fn; + struct skeletons skeletons = {}; + int i; + + old_print_fn = libbpf_set_print(libbpf_debug_print); + + root_netns_fd = open("/proc/self/ns/net", O_RDONLY); + if (!ASSERT_GE(root_netns_fd, 0, "open /proc/self/ns/net")) + goto out; + + skeletons.xdp_dummy = xdp_dummy__open_and_load(); + if (!ASSERT_OK_PTR(skeletons.xdp_dummy, "xdp_dummy__open_and_load")) + goto out; + + skeletons.xdp_tx = xdp_tx__open_and_load(); + if (!ASSERT_OK_PTR(skeletons.xdp_tx, "xdp_tx__open_and_load")) + goto out; + + skeletons.xdp_redirect_multi_kern = xdp_redirect_multi_kern__open_and_load(); + if (!ASSERT_OK_PTR(skeletons.xdp_redirect_multi_kern, + "xdp_redirect_multi_kern__open_and_load")) + goto out; + + if (!test__start_subtest("xdp_bonding_attach")) + test_xdp_bonding_attach(&skeletons); + + for (i = 0; i < ARRAY_SIZE(bond_test_cases); i++) { + struct bond_test_case *test_case = &bond_test_cases[i]; + + if (!test__start_subtest(test_case->name)) + test_xdp_bonding_with_mode( + &skeletons, + test_case->mode, + test_case->xmit_policy); + } + + if (!test__start_subtest("xdp_bonding_redirect_multi")) + test_xdp_bonding_redirect_multi(&skeletons); + +out: + xdp_dummy__destroy(skeletons.xdp_dummy); + xdp_tx__destroy(skeletons.xdp_tx); + xdp_redirect_multi_kern__destroy(skeletons.xdp_redirect_multi_kern); + + libbpf_set_print(old_print_fn); + if (root_netns_fd >= 0) + close(root_netns_fd); +} -- 2.11.0