tools/testing/selftests/bpf/prog_tests/xdp_bonding.c

   1 // SPDX-License-Identifier: GPL-2.0
   2
   3 /**
   4  * Test XDP bonding support
   5  *
   6  * Sets up two bonded veth pairs between two fresh namespaces
   7  * and verifies that XDP_TX program loaded on a bond device
   8  * are correctly loaded onto the slave devices and XDP_TX'd
   9  * packets are balanced using bonding.
  10  */
  11
  12 #define _GNU_SOURCE
  13 #include <sched.h>
  14 #include <net/if.h>
  15 #include <linux/if_link.h>
  16 #include "test_progs.h"
  17 #include "network_helpers.h"
  18 #include <linux/if_bonding.h>
  19 #include <linux/limits.h>
  20 #include <linux/udp.h>
  21
  22 #include "xdp_dummy.skel.h"
  23 #include "xdp_redirect_multi_kern.skel.h"
  24 #include "xdp_tx.skel.h"
  25
  26 #define BOND1_MAC {0x00, 0x11, 0x22, 0x33, 0x44, 0x55}
  27 #define BOND1_MAC_STR "00:11:22:33:44:55"
  28 #define BOND2_MAC {0x00, 0x22, 0x33, 0x44, 0x55, 0x66}
  29 #define BOND2_MAC_STR "00:22:33:44:55:66"
  30 #define NPACKETS 100
  31
  32 static int root_netns_fd = -1;
  33
  34 static void restore_root_netns(void)
  35 {
  36         ASSERT_OK(setns(root_netns_fd, CLONE_NEWNET), "restore_root_netns");
  37 }
  38
  39 static int setns_by_name(char *name)
  40 {
  41         int nsfd, err;
  42         char nspath[PATH_MAX];
  43
  44         snprintf(nspath, sizeof(nspath), "%s/%s", "/var/run/netns", name);
  45         nsfd = open(nspath, O_RDONLY | O_CLOEXEC);
  46         if (nsfd < 0)
  47                 return -1;
  48
  49         err = setns(nsfd, CLONE_NEWNET);
  50         close(nsfd);
  51         return err;
  52 }
  53
  54 static int get_rx_packets(const char *iface)
  55 {
  56         FILE *f;
  57         char line[512];
  58         int iface_len = strlen(iface);
  59
  60         f = fopen("/proc/net/dev", "r");
  61         if (!f)
  62                 return -1;
  63
  64         while (fgets(line, sizeof(line), f)) {
  65                 char *p = line;
  66
  67                 while (*p == ' ')
  68                         p++; /* skip whitespace */
  69                 if (!strncmp(p, iface, iface_len)) {
  70                         p += iface_len;
  71                         if (*p++ != ':')
  72                                 continue;
  73                         while (*p == ' ')
  74                                 p++; /* skip whitespace */
  75                         while (*p && *p != ' ')
  76                                 p++; /* skip rx bytes */
  77                         while (*p == ' ')
  78                                 p++; /* skip whitespace */
  79                         fclose(f);
  80                         return atoi(p);
  81                 }
  82         }
  83         fclose(f);
  84         return -1;
  85 }
  86
  87 #define MAX_BPF_LINKS 8
  88
  89 struct skeletons {
  90         struct xdp_dummy *xdp_dummy;
  91         struct xdp_tx *xdp_tx;
  92         struct xdp_redirect_multi_kern *xdp_redirect_multi_kern;
  93
  94         int nlinks;
  95         struct bpf_link *links[MAX_BPF_LINKS];
  96 };
  97
  98 static int xdp_attach(struct skeletons *skeletons, struct bpf_program *prog, char *iface)
  99 {
 100         struct bpf_link *link;
 101         int ifindex;
 102
 103         ifindex = if_nametoindex(iface);
 104         if (!ASSERT_GT(ifindex, 0, "get ifindex"))
 105                 return -1;
 106
 107         if (!ASSERT_LE(skeletons->nlinks+1, MAX_BPF_LINKS, "too many XDP programs attached"))
 108                 return -1;
 109
 110         link = bpf_program__attach_xdp(prog, ifindex);
 111         if (!ASSERT_OK_PTR(link, "attach xdp program"))
 112                 return -1;
 113
 114         skeletons->links[skeletons->nlinks++] = link;
 115         return 0;
 116 }
 117
 118 enum {
 119         BOND_ONE_NO_ATTACH = 0,
 120         BOND_BOTH_AND_ATTACH,
 121 };
 122
 123 static const char * const mode_names[] = {
 124         [BOND_MODE_ROUNDROBIN]   = "balance-rr",
 125         [BOND_MODE_ACTIVEBACKUP] = "active-backup",
 126         [BOND_MODE_XOR]          = "balance-xor",
 127         [BOND_MODE_BROADCAST]    = "broadcast",
 128         [BOND_MODE_8023AD]       = "802.3ad",
 129         [BOND_MODE_TLB]          = "balance-tlb",
 130         [BOND_MODE_ALB]          = "balance-alb",
 131 };
 132
 133 static const char * const xmit_policy_names[] = {
 134         [BOND_XMIT_POLICY_LAYER2]       = "layer2",
 135         [BOND_XMIT_POLICY_LAYER34]      = "layer3+4",
 136         [BOND_XMIT_POLICY_LAYER23]      = "layer2+3",
 137         [BOND_XMIT_POLICY_ENCAP23]      = "encap2+3",
 138         [BOND_XMIT_POLICY_ENCAP34]      = "encap3+4",
 139 };
 140
 141 static int bonding_setup(struct skeletons *skeletons, int mode, int xmit_policy,
 142                          int bond_both_attach)
 143 {
 144 #define SYS(fmt, ...)                                           \
 145         ({                                                      \
 146                 char cmd[1024];                                 \
 147                 snprintf(cmd, sizeof(cmd), fmt, ##__VA_ARGS__); \
 148                 if (!ASSERT_OK(system(cmd), cmd))               \
 149                         return -1;                              \
 150         })
 151
 152         SYS("ip netns add ns_dst");
 153         SYS("ip link add veth1_1 type veth peer name veth2_1 netns ns_dst");
 154         SYS("ip link add veth1_2 type veth peer name veth2_2 netns ns_dst");
 155
 156         SYS("ip link add bond1 type bond mode %s xmit_hash_policy %s",
 157             mode_names[mode], xmit_policy_names[xmit_policy]);
 158         SYS("ip link set bond1 up address " BOND1_MAC_STR " addrgenmode none");
 159         SYS("ip -netns ns_dst link add bond2 type bond mode %s xmit_hash_policy %s",
 160             mode_names[mode], xmit_policy_names[xmit_policy]);
 161         SYS("ip -netns ns_dst link set bond2 up address " BOND2_MAC_STR " addrgenmode none");
 162
 163         SYS("ip link set veth1_1 master bond1");
 164         if (bond_both_attach == BOND_BOTH_AND_ATTACH) {
 165                 SYS("ip link set veth1_2 master bond1");
 166         } else {
 167                 SYS("ip link set veth1_2 up addrgenmode none");
 168
 169                 if (xdp_attach(skeletons, skeletons->xdp_dummy->progs.xdp_dummy_prog, "veth1_2"))
 170                         return -1;
 171         }
 172
 173         SYS("ip -netns ns_dst link set veth2_1 master bond2");
 174
 175         if (bond_both_attach == BOND_BOTH_AND_ATTACH)
 176                 SYS("ip -netns ns_dst link set veth2_2 master bond2");
 177         else
 178                 SYS("ip -netns ns_dst link set veth2_2 up addrgenmode none");
 179
 180         /* Load a dummy program on sending side as with veth peer needs to have a
 181          * XDP program loaded as well.
 182          */
 183         if (xdp_attach(skeletons, skeletons->xdp_dummy->progs.xdp_dummy_prog, "bond1"))
 184                 return -1;
 185
 186         if (bond_both_attach == BOND_BOTH_AND_ATTACH) {
 187                 if (!ASSERT_OK(setns_by_name("ns_dst"), "set netns to ns_dst"))
 188                         return -1;
 189
 190                 if (xdp_attach(skeletons, skeletons->xdp_tx->progs.xdp_tx, "bond2"))
 191                         return -1;
 192
 193                 restore_root_netns();
 194         }
 195
 196         return 0;
 197
 198 #undef SYS
 199 }
 200
 201 static void bonding_cleanup(struct skeletons *skeletons)
 202 {
 203         restore_root_netns();
 204         while (skeletons->nlinks) {
 205                 skeletons->nlinks--;
 206                 bpf_link__destroy(skeletons->links[skeletons->nlinks]);
 207         }
 208         ASSERT_OK(system("ip link delete bond1"), "delete bond1");
 209         ASSERT_OK(system("ip link delete veth1_1"), "delete veth1_1");
 210         ASSERT_OK(system("ip link delete veth1_2"), "delete veth1_2");
 211         ASSERT_OK(system("ip netns delete ns_dst"), "delete ns_dst");
 212 }
 213
 214 static int send_udp_packets(int vary_dst_ip)
 215 {
 216         struct ethhdr eh = {
 217                 .h_source = BOND1_MAC,
 218                 .h_dest = BOND2_MAC,
 219                 .h_proto = htons(ETH_P_IP),
 220         };
 221         struct iphdr iph = {};
 222         struct udphdr uh = {};
 223         uint8_t buf[128];
 224         int i, s = -1;
 225         int ifindex;
 226
 227         s = socket(AF_PACKET, SOCK_RAW, IPPROTO_RAW);
 228         if (!ASSERT_GE(s, 0, "socket"))
 229                 goto err;
 230
 231         ifindex = if_nametoindex("bond1");
 232         if (!ASSERT_GT(ifindex, 0, "get bond1 ifindex"))
 233                 goto err;
 234
 235         iph.ihl = 5;
 236         iph.version = 4;
 237         iph.tos = 16;
 238         iph.id = 1;
 239         iph.ttl = 64;
 240         iph.protocol = IPPROTO_UDP;
 241         iph.saddr = 1;
 242         iph.daddr = 2;
 243         iph.tot_len = htons(sizeof(buf) - ETH_HLEN);
 244         iph.check = 0;
 245
 246         for (i = 1; i <= NPACKETS; i++) {
 247                 int n;
 248                 struct sockaddr_ll saddr_ll = {
 249                         .sll_ifindex = ifindex,
 250                         .sll_halen = ETH_ALEN,
 251                         .sll_addr = BOND2_MAC,
 252                 };
 253
 254                 /* vary the UDP destination port for even distribution with roundrobin/xor modes */
 255                 uh.dest++;
 256
 257                 if (vary_dst_ip)
 258                         iph.daddr++;
 259
 260                 /* construct a packet */
 261                 memcpy(buf, &eh, sizeof(eh));
 262                 memcpy(buf + sizeof(eh), &iph, sizeof(iph));
 263                 memcpy(buf + sizeof(eh) + sizeof(iph), &uh, sizeof(uh));
 264
 265                 n = sendto(s, buf, sizeof(buf), 0, (struct sockaddr *)&saddr_ll, sizeof(saddr_ll));
 266                 if (!ASSERT_EQ(n, sizeof(buf), "sendto"))
 267                         goto err;
 268         }
 269
 270         return 0;
 271
 272 err:
 273         if (s >= 0)
 274                 close(s);
 275         return -1;
 276 }
 277
 278 static void test_xdp_bonding_with_mode(struct skeletons *skeletons, int mode, int xmit_policy)
 279 {
 280         int bond1_rx;
 281
 282         if (bonding_setup(skeletons, mode, xmit_policy, BOND_BOTH_AND_ATTACH))
 283                 goto out;
 284
 285         if (send_udp_packets(xmit_policy != BOND_XMIT_POLICY_LAYER34))
 286                 goto out;
 287
 288         bond1_rx = get_rx_packets("bond1");
 289         ASSERT_EQ(bond1_rx, NPACKETS, "expected more received packets");
 290
 291         switch (mode) {
 292         case BOND_MODE_ROUNDROBIN:
 293         case BOND_MODE_XOR: {
 294                 int veth1_rx = get_rx_packets("veth1_1");
 295                 int veth2_rx = get_rx_packets("veth1_2");
 296                 int diff = abs(veth1_rx - veth2_rx);
 297
 298                 ASSERT_GE(veth1_rx + veth2_rx, NPACKETS, "expected more packets");
 299
 300                 switch (xmit_policy) {
 301                 case BOND_XMIT_POLICY_LAYER2:
 302                         ASSERT_GE(diff, NPACKETS,
 303                                   "expected packets on only one of the interfaces");
 304                         break;
 305                 case BOND_XMIT_POLICY_LAYER23:
 306                 case BOND_XMIT_POLICY_LAYER34:
 307                         ASSERT_LT(diff, NPACKETS/2,
 308                                   "expected even distribution of packets");
 309                         break;
 310                 default:
 311                         PRINT_FAIL("Unimplemented xmit_policy=%d\n", xmit_policy);
 312                         break;
 313                 }
 314                 break;
 315         }
 316         case BOND_MODE_ACTIVEBACKUP: {
 317                 int veth1_rx = get_rx_packets("veth1_1");
 318                 int veth2_rx = get_rx_packets("veth1_2");
 319                 int diff = abs(veth1_rx - veth2_rx);
 320
 321                 ASSERT_GE(diff, NPACKETS,
 322                           "expected packets on only one of the interfaces");
 323                 break;
 324         }
 325         default:
 326                 PRINT_FAIL("Unimplemented xmit_policy=%d\n", xmit_policy);
 327                 break;
 328         }
 329
 330 out:
 331         bonding_cleanup(skeletons);
 332 }
 333
 334 /* Test the broadcast redirection using xdp_redirect_map_multi_prog and adding
 335  * all the interfaces to it and checking that broadcasting won't send the packet
 336  * to neither the ingress bond device (bond2) or its slave (veth2_1).
 337  */
 338 static void test_xdp_bonding_redirect_multi(struct skeletons *skeletons)
 339 {
 340         static const char * const ifaces[] = {"bond2", "veth2_1", "veth2_2"};
 341         int veth1_1_rx, veth1_2_rx;
 342         int err;
 343
 344         if (bonding_setup(skeletons, BOND_MODE_ROUNDROBIN, BOND_XMIT_POLICY_LAYER23,
 345                           BOND_ONE_NO_ATTACH))
 346                 goto out;
 347
 348
 349         if (!ASSERT_OK(setns_by_name("ns_dst"), "could not set netns to ns_dst"))
 350                 goto out;
 351
 352         /* populate the devmap with the relevant interfaces */
 353         for (int i = 0; i < ARRAY_SIZE(ifaces); i++) {
 354                 int ifindex = if_nametoindex(ifaces[i]);
 355                 int map_fd = bpf_map__fd(skeletons->xdp_redirect_multi_kern->maps.map_all);
 356
 357                 if (!ASSERT_GT(ifindex, 0, "could not get interface index"))
 358                         goto out;
 359
 360                 err = bpf_map_update_elem(map_fd, &ifindex, &ifindex, 0);
 361                 if (!ASSERT_OK(err, "add interface to map_all"))
 362                         goto out;
 363         }
 364
 365         if (xdp_attach(skeletons,
 366                        skeletons->xdp_redirect_multi_kern->progs.xdp_redirect_map_multi_prog,
 367                        "bond2"))
 368                 goto out;
 369
 370         restore_root_netns();
 371
 372         if (send_udp_packets(BOND_MODE_ROUNDROBIN))
 373                 goto out;
 374
 375         veth1_1_rx = get_rx_packets("veth1_1");
 376         veth1_2_rx = get_rx_packets("veth1_2");
 377
 378         ASSERT_EQ(veth1_1_rx, 0, "expected no packets on veth1_1");
 379         ASSERT_GE(veth1_2_rx, NPACKETS, "expected packets on veth1_2");
 380
 381 out:
 382         restore_root_netns();
 383         bonding_cleanup(skeletons);
 384 }
 385
 386 /* Test that XDP programs cannot be attached to both the bond master and slaves simultaneously */
 387 static void test_xdp_bonding_attach(struct skeletons *skeletons)
 388 {
 389         struct bpf_link *link = NULL;
 390         struct bpf_link *link2 = NULL;
 391         int veth, bond, err;
 392
 393         if (!ASSERT_OK(system("ip link add veth type veth"), "add veth"))
 394                 goto out;
 395         if (!ASSERT_OK(system("ip link add bond type bond"), "add bond"))
 396                 goto out;
 397
 398         veth = if_nametoindex("veth");
 399         if (!ASSERT_GE(veth, 0, "if_nametoindex veth"))
 400                 goto out;
 401         bond = if_nametoindex("bond");
 402         if (!ASSERT_GE(bond, 0, "if_nametoindex bond"))
 403                 goto out;
 404
 405         /* enslaving with a XDP program loaded is allowed */
 406         link = bpf_program__attach_xdp(skeletons->xdp_dummy->progs.xdp_dummy_prog, veth);
 407         if (!ASSERT_OK_PTR(link, "attach program to veth"))
 408                 goto out;
 409
 410         err = system("ip link set veth master bond");
 411         if (!ASSERT_OK(err, "set veth master"))
 412                 goto out;
 413
 414         bpf_link__destroy(link);
 415         link = NULL;
 416
 417         /* attaching to slave when master has no program is allowed */
 418         link = bpf_program__attach_xdp(skeletons->xdp_dummy->progs.xdp_dummy_prog, veth);
 419         if (!ASSERT_OK_PTR(link, "attach program to slave when enslaved"))
 420                 goto out;
 421
 422         /* attaching to master not allowed when slave has program loaded */
 423         link2 = bpf_program__attach_xdp(skeletons->xdp_dummy->progs.xdp_dummy_prog, bond);
 424         if (!ASSERT_ERR_PTR(link2, "attach program to master when slave has program"))
 425                 goto out;
 426
 427         bpf_link__destroy(link);
 428         link = NULL;
 429
 430         /* attaching XDP program to master allowed when slave has no program */
 431         link = bpf_program__attach_xdp(skeletons->xdp_dummy->progs.xdp_dummy_prog, bond);
 432         if (!ASSERT_OK_PTR(link, "attach program to master"))
 433                 goto out;
 434
 435         /* attaching to slave not allowed when master has program loaded */
 436         link2 = bpf_program__attach_xdp(skeletons->xdp_dummy->progs.xdp_dummy_prog, veth);
 437         if (!ASSERT_ERR_PTR(link2, "attach program to slave when master has program"))
 438                 goto out;
 439
 440         bpf_link__destroy(link);
 441         link = NULL;
 442
 443         /* test program unwinding with a non-XDP slave */
 444         if (!ASSERT_OK(system("ip link add vxlan type vxlan id 1 remote 1.2.3.4 dstport 0 dev lo"),
 445                        "add vxlan"))
 446                 goto out;
 447
 448         err = system("ip link set vxlan master bond");
 449         if (!ASSERT_OK(err, "set vxlan master"))
 450                 goto out;
 451
 452         /* attaching not allowed when one slave does not support XDP */
 453         link = bpf_program__attach_xdp(skeletons->xdp_dummy->progs.xdp_dummy_prog, bond);
 454         if (!ASSERT_ERR_PTR(link, "attach program to master when slave does not support XDP"))
 455                 goto out;
 456
 457 out:
 458         bpf_link__destroy(link);
 459         bpf_link__destroy(link2);
 460
 461         system("ip link del veth");
 462         system("ip link del bond");
 463         system("ip link del vxlan");
 464 }
 465
 466 /* Test with nested bonding devices to catch issue with negative jump label count */
 467 static void test_xdp_bonding_nested(struct skeletons *skeletons)
 468 {
 469         struct bpf_link *link = NULL;
 470         int bond, err;
 471
 472         if (!ASSERT_OK(system("ip link add bond type bond"), "add bond"))
 473                 goto out;
 474
 475         bond = if_nametoindex("bond");
 476         if (!ASSERT_GE(bond, 0, "if_nametoindex bond"))
 477                 goto out;
 478
 479         if (!ASSERT_OK(system("ip link add bond_nest1 type bond"), "add bond_nest1"))
 480                 goto out;
 481
 482         err = system("ip link set bond_nest1 master bond");
 483         if (!ASSERT_OK(err, "set bond_nest1 master"))
 484                 goto out;
 485
 486         if (!ASSERT_OK(system("ip link add bond_nest2 type bond"), "add bond_nest1"))
 487                 goto out;
 488
 489         err = system("ip link set bond_nest2 master bond_nest1");
 490         if (!ASSERT_OK(err, "set bond_nest2 master"))
 491                 goto out;
 492
 493         link = bpf_program__attach_xdp(skeletons->xdp_dummy->progs.xdp_dummy_prog, bond);
 494         ASSERT_OK_PTR(link, "attach program to master");
 495
 496 out:
 497         bpf_link__destroy(link);
 498         system("ip link del bond");
 499         system("ip link del bond_nest1");
 500         system("ip link del bond_nest2");
 501 }
 502
 503 static int libbpf_debug_print(enum libbpf_print_level level,
 504                               const char *format, va_list args)
 505 {
 506         if (level != LIBBPF_WARN)
 507                 vprintf(format, args);
 508         return 0;
 509 }
 510
 511 struct bond_test_case {
 512         char *name;
 513         int mode;
 514         int xmit_policy;
 515 };
 516
 517 static struct bond_test_case bond_test_cases[] = {
 518         { "xdp_bonding_roundrobin", BOND_MODE_ROUNDROBIN, BOND_XMIT_POLICY_LAYER23, },
 519         { "xdp_bonding_activebackup", BOND_MODE_ACTIVEBACKUP, BOND_XMIT_POLICY_LAYER23 },
 520
 521         { "xdp_bonding_xor_layer2", BOND_MODE_XOR, BOND_XMIT_POLICY_LAYER2, },
 522         { "xdp_bonding_xor_layer23", BOND_MODE_XOR, BOND_XMIT_POLICY_LAYER23, },
 523         { "xdp_bonding_xor_layer34", BOND_MODE_XOR, BOND_XMIT_POLICY_LAYER34, },
 524 };
 525
 526 void serial_test_xdp_bonding(void)
 527 {
 528         libbpf_print_fn_t old_print_fn;
 529         struct skeletons skeletons = {};
 530         int i;
 531
 532         old_print_fn = libbpf_set_print(libbpf_debug_print);
 533
 534         root_netns_fd = open("/proc/self/ns/net", O_RDONLY);
 535         if (!ASSERT_GE(root_netns_fd, 0, "open /proc/self/ns/net"))
 536                 goto out;
 537
 538         skeletons.xdp_dummy = xdp_dummy__open_and_load();
 539         if (!ASSERT_OK_PTR(skeletons.xdp_dummy, "xdp_dummy__open_and_load"))
 540                 goto out;
 541
 542         skeletons.xdp_tx = xdp_tx__open_and_load();
 543         if (!ASSERT_OK_PTR(skeletons.xdp_tx, "xdp_tx__open_and_load"))
 544                 goto out;
 545
 546         skeletons.xdp_redirect_multi_kern = xdp_redirect_multi_kern__open_and_load();
 547         if (!ASSERT_OK_PTR(skeletons.xdp_redirect_multi_kern,
 548                            "xdp_redirect_multi_kern__open_and_load"))
 549                 goto out;
 550
 551         if (test__start_subtest("xdp_bonding_attach"))
 552                 test_xdp_bonding_attach(&skeletons);
 553
 554         if (test__start_subtest("xdp_bonding_nested"))
 555                 test_xdp_bonding_nested(&skeletons);
 556
 557         for (i = 0; i < ARRAY_SIZE(bond_test_cases); i++) {
 558                 struct bond_test_case *test_case = &bond_test_cases[i];
 559
 560                 if (test__start_subtest(test_case->name))
 561                         test_xdp_bonding_with_mode(
 562                                 &skeletons,
 563                                 test_case->mode,
 564                                 test_case->xmit_policy);
 565         }
 566
 567         if (test__start_subtest("xdp_bonding_redirect_multi"))
 568                 test_xdp_bonding_redirect_multi(&skeletons);
 569
 570 out:
 571         xdp_dummy__destroy(skeletons.xdp_dummy);
 572         xdp_tx__destroy(skeletons.xdp_tx);
 573         xdp_redirect_multi_kern__destroy(skeletons.xdp_redirect_multi_kern);
 574
 575         libbpf_set_print(old_print_fn);
 576         if (root_netns_fd >= 0)
 577                 close(root_netns_fd);
 578 }