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         uint8_t buf[128] = {};
 222         struct iphdr *iph = (struct iphdr *)(buf + sizeof(eh));
 223         struct udphdr *uh = (struct udphdr *)(buf + sizeof(eh) + sizeof(*iph));
 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         memcpy(buf, &eh, sizeof(eh));
 236         iph->ihl = 5;
 237         iph->version = 4;
 238         iph->tos = 16;
 239         iph->id = 1;
 240         iph->ttl = 64;
 241         iph->protocol = IPPROTO_UDP;
 242         iph->saddr = 1;
 243         iph->daddr = 2;
 244         iph->tot_len = htons(sizeof(buf) - ETH_HLEN);
 245         iph->check = 0;
 246
 247         for (i = 1; i <= NPACKETS; i++) {
 248                 int n;
 249                 struct sockaddr_ll saddr_ll = {
 250                         .sll_ifindex = ifindex,
 251                         .sll_halen = ETH_ALEN,
 252                         .sll_addr = BOND2_MAC,
 253                 };
 254
 255                 /* vary the UDP destination port for even distribution with roundrobin/xor modes */
 256                 uh->dest++;
 257
 258                 if (vary_dst_ip)
 259                         iph->daddr++;
 260
 261                 n = sendto(s, buf, sizeof(buf), 0, (struct sockaddr *)&saddr_ll, sizeof(saddr_ll));
 262                 if (!ASSERT_EQ(n, sizeof(buf), "sendto"))
 263                         goto err;
 264         }
 265
 266         return 0;
 267
 268 err:
 269         if (s >= 0)
 270                 close(s);
 271         return -1;
 272 }
 273
 274 static void test_xdp_bonding_with_mode(struct skeletons *skeletons, int mode, int xmit_policy)
 275 {
 276         int bond1_rx;
 277
 278         if (bonding_setup(skeletons, mode, xmit_policy, BOND_BOTH_AND_ATTACH))
 279                 goto out;
 280
 281         if (send_udp_packets(xmit_policy != BOND_XMIT_POLICY_LAYER34))
 282                 goto out;
 283
 284         bond1_rx = get_rx_packets("bond1");
 285         ASSERT_EQ(bond1_rx, NPACKETS, "expected more received packets");
 286
 287         switch (mode) {
 288         case BOND_MODE_ROUNDROBIN:
 289         case BOND_MODE_XOR: {
 290                 int veth1_rx = get_rx_packets("veth1_1");
 291                 int veth2_rx = get_rx_packets("veth1_2");
 292                 int diff = abs(veth1_rx - veth2_rx);
 293
 294                 ASSERT_GE(veth1_rx + veth2_rx, NPACKETS, "expected more packets");
 295
 296                 switch (xmit_policy) {
 297                 case BOND_XMIT_POLICY_LAYER2:
 298                         ASSERT_GE(diff, NPACKETS,
 299                                   "expected packets on only one of the interfaces");
 300                         break;
 301                 case BOND_XMIT_POLICY_LAYER23:
 302                 case BOND_XMIT_POLICY_LAYER34:
 303                         ASSERT_LT(diff, NPACKETS/2,
 304                                   "expected even distribution of packets");
 305                         break;
 306                 default:
 307                         PRINT_FAIL("Unimplemented xmit_policy=%d\n", xmit_policy);
 308                         break;
 309                 }
 310                 break;
 311         }
 312         case BOND_MODE_ACTIVEBACKUP: {
 313                 int veth1_rx = get_rx_packets("veth1_1");
 314                 int veth2_rx = get_rx_packets("veth1_2");
 315                 int diff = abs(veth1_rx - veth2_rx);
 316
 317                 ASSERT_GE(diff, NPACKETS,
 318                           "expected packets on only one of the interfaces");
 319                 break;
 320         }
 321         default:
 322                 PRINT_FAIL("Unimplemented xmit_policy=%d\n", xmit_policy);
 323                 break;
 324         }
 325
 326 out:
 327         bonding_cleanup(skeletons);
 328 }
 329
 330 /* Test the broadcast redirection using xdp_redirect_map_multi_prog and adding
 331  * all the interfaces to it and checking that broadcasting won't send the packet
 332  * to neither the ingress bond device (bond2) or its slave (veth2_1).
 333  */
 334 static void test_xdp_bonding_redirect_multi(struct skeletons *skeletons)
 335 {
 336         static const char * const ifaces[] = {"bond2", "veth2_1", "veth2_2"};
 337         int veth1_1_rx, veth1_2_rx;
 338         int err;
 339
 340         if (bonding_setup(skeletons, BOND_MODE_ROUNDROBIN, BOND_XMIT_POLICY_LAYER23,
 341                           BOND_ONE_NO_ATTACH))
 342                 goto out;
 343
 344
 345         if (!ASSERT_OK(setns_by_name("ns_dst"), "could not set netns to ns_dst"))
 346                 goto out;
 347
 348         /* populate the devmap with the relevant interfaces */
 349         for (int i = 0; i < ARRAY_SIZE(ifaces); i++) {
 350                 int ifindex = if_nametoindex(ifaces[i]);
 351                 int map_fd = bpf_map__fd(skeletons->xdp_redirect_multi_kern->maps.map_all);
 352
 353                 if (!ASSERT_GT(ifindex, 0, "could not get interface index"))
 354                         goto out;
 355
 356                 err = bpf_map_update_elem(map_fd, &ifindex, &ifindex, 0);
 357                 if (!ASSERT_OK(err, "add interface to map_all"))
 358                         goto out;
 359         }
 360
 361         if (xdp_attach(skeletons,
 362                        skeletons->xdp_redirect_multi_kern->progs.xdp_redirect_map_multi_prog,
 363                        "bond2"))
 364                 goto out;
 365
 366         restore_root_netns();
 367
 368         if (send_udp_packets(BOND_MODE_ROUNDROBIN))
 369                 goto out;
 370
 371         veth1_1_rx = get_rx_packets("veth1_1");
 372         veth1_2_rx = get_rx_packets("veth1_2");
 373
 374         ASSERT_EQ(veth1_1_rx, 0, "expected no packets on veth1_1");
 375         ASSERT_GE(veth1_2_rx, NPACKETS, "expected packets on veth1_2");
 376
 377 out:
 378         restore_root_netns();
 379         bonding_cleanup(skeletons);
 380 }
 381
 382 /* Test that XDP programs cannot be attached to both the bond master and slaves simultaneously */
 383 static void test_xdp_bonding_attach(struct skeletons *skeletons)
 384 {
 385         struct bpf_link *link = NULL;
 386         struct bpf_link *link2 = NULL;
 387         int veth, bond;
 388         int err;
 389
 390         if (!ASSERT_OK(system("ip link add veth type veth"), "add veth"))
 391                 goto out;
 392         if (!ASSERT_OK(system("ip link add bond type bond"), "add bond"))
 393                 goto out;
 394
 395         veth = if_nametoindex("veth");
 396         if (!ASSERT_GE(veth, 0, "if_nametoindex veth"))
 397                 goto out;
 398         bond = if_nametoindex("bond");
 399         if (!ASSERT_GE(bond, 0, "if_nametoindex bond"))
 400                 goto out;
 401
 402         /* enslaving with a XDP program loaded fails */
 403         link = bpf_program__attach_xdp(skeletons->xdp_dummy->progs.xdp_dummy_prog, veth);
 404         if (!ASSERT_OK_PTR(link, "attach program to veth"))
 405                 goto out;
 406
 407         err = system("ip link set veth master bond");
 408         if (!ASSERT_NEQ(err, 0, "attaching slave with xdp program expected to fail"))
 409                 goto out;
 410
 411         bpf_link__destroy(link);
 412         link = NULL;
 413
 414         err = system("ip link set veth master bond");
 415         if (!ASSERT_OK(err, "set veth master"))
 416                 goto out;
 417
 418         /* attaching to slave when master has no program is allowed */
 419         link = bpf_program__attach_xdp(skeletons->xdp_dummy->progs.xdp_dummy_prog, veth);
 420         if (!ASSERT_OK_PTR(link, "attach program to slave when enslaved"))
 421                 goto out;
 422
 423         /* attaching to master not allowed when slave has program loaded */
 424         link2 = bpf_program__attach_xdp(skeletons->xdp_dummy->progs.xdp_dummy_prog, bond);
 425         if (!ASSERT_ERR_PTR(link2, "attach program to master when slave has program"))
 426                 goto out;
 427
 428         bpf_link__destroy(link);
 429         link = NULL;
 430
 431         /* attaching XDP program to master allowed when slave has no program */
 432         link = bpf_program__attach_xdp(skeletons->xdp_dummy->progs.xdp_dummy_prog, bond);
 433         if (!ASSERT_OK_PTR(link, "attach program to master"))
 434                 goto out;
 435
 436         /* attaching to slave not allowed when master has program loaded */
 437         link2 = bpf_program__attach_xdp(skeletons->xdp_dummy->progs.xdp_dummy_prog, bond);
 438         ASSERT_ERR_PTR(link2, "attach program to slave when master has program");
 439
 440 out:
 441         bpf_link__destroy(link);
 442         bpf_link__destroy(link2);
 443
 444         system("ip link del veth");
 445         system("ip link del bond");
 446 }
 447
 448 static int libbpf_debug_print(enum libbpf_print_level level,
 449                               const char *format, va_list args)
 450 {
 451         if (level != LIBBPF_WARN)
 452                 vprintf(format, args);
 453         return 0;
 454 }
 455
 456 struct bond_test_case {
 457         char *name;
 458         int mode;
 459         int xmit_policy;
 460 };
 461
 462 static struct bond_test_case bond_test_cases[] = {
 463         { "xdp_bonding_roundrobin", BOND_MODE_ROUNDROBIN, BOND_XMIT_POLICY_LAYER23, },
 464         { "xdp_bonding_activebackup", BOND_MODE_ACTIVEBACKUP, BOND_XMIT_POLICY_LAYER23 },
 465
 466         { "xdp_bonding_xor_layer2", BOND_MODE_XOR, BOND_XMIT_POLICY_LAYER2, },
 467         { "xdp_bonding_xor_layer23", BOND_MODE_XOR, BOND_XMIT_POLICY_LAYER23, },
 468         { "xdp_bonding_xor_layer34", BOND_MODE_XOR, BOND_XMIT_POLICY_LAYER34, },
 469 };
 470
 471 void test_xdp_bonding(void)
 472 {
 473         libbpf_print_fn_t old_print_fn;
 474         struct skeletons skeletons = {};
 475         int i;
 476
 477         old_print_fn = libbpf_set_print(libbpf_debug_print);
 478
 479         root_netns_fd = open("/proc/self/ns/net", O_RDONLY);
 480         if (!ASSERT_GE(root_netns_fd, 0, "open /proc/self/ns/net"))
 481                 goto out;
 482
 483         skeletons.xdp_dummy = xdp_dummy__open_and_load();
 484         if (!ASSERT_OK_PTR(skeletons.xdp_dummy, "xdp_dummy__open_and_load"))
 485                 goto out;
 486
 487         skeletons.xdp_tx = xdp_tx__open_and_load();
 488         if (!ASSERT_OK_PTR(skeletons.xdp_tx, "xdp_tx__open_and_load"))
 489                 goto out;
 490
 491         skeletons.xdp_redirect_multi_kern = xdp_redirect_multi_kern__open_and_load();
 492         if (!ASSERT_OK_PTR(skeletons.xdp_redirect_multi_kern,
 493                            "xdp_redirect_multi_kern__open_and_load"))
 494                 goto out;
 495
 496         if (test__start_subtest("xdp_bonding_attach"))
 497                 test_xdp_bonding_attach(&skeletons);
 498
 499         for (i = 0; i < ARRAY_SIZE(bond_test_cases); i++) {
 500                 struct bond_test_case *test_case = &bond_test_cases[i];
 501
 502                 if (test__start_subtest(test_case->name))
 503                         test_xdp_bonding_with_mode(
 504                                 &skeletons,
 505                                 test_case->mode,
 506                                 test_case->xmit_policy);
 507         }
 508
 509         if (test__start_subtest("xdp_bonding_redirect_multi"))
 510                 test_xdp_bonding_redirect_multi(&skeletons);
 511
 512 out:
 513         xdp_dummy__destroy(skeletons.xdp_dummy);
 514         xdp_tx__destroy(skeletons.xdp_tx);
 515         xdp_redirect_multi_kern__destroy(skeletons.xdp_redirect_multi_kern);
 516
 517         libbpf_set_print(old_print_fn);
 518         if (root_netns_fd >= 0)
 519                 close(root_netns_fd);
 520 }