tools/testing/selftests/net/psock_fanout.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Copyright 2013 Google Inc.
   4  * Author: Willem de Bruijn (willemb@google.com)
   5  *
   6  * A basic test of packet socket fanout behavior.
   7  *
   8  * Control:
   9  * - create fanout fails as expected with illegal flag combinations
  10  * - join   fanout fails as expected with diverging types or flags
  11  *
  12  * Datapath:
  13  *   Open a pair of packet sockets and a pair of INET sockets, send a known
  14  *   number of packets across the two INET sockets and count the number of
  15  *   packets enqueued onto the two packet sockets.
  16  *
  17  *   The test currently runs for
  18  *   - PACKET_FANOUT_HASH
  19  *   - PACKET_FANOUT_HASH with PACKET_FANOUT_FLAG_ROLLOVER
  20  *   - PACKET_FANOUT_LB
  21  *   - PACKET_FANOUT_CPU
  22  *   - PACKET_FANOUT_ROLLOVER
  23  *   - PACKET_FANOUT_CBPF
  24  *   - PACKET_FANOUT_EBPF
  25  *
  26  * Todo:
  27  * - functionality: PACKET_FANOUT_FLAG_DEFRAG
  28  */
  29
  30 #define _GNU_SOURCE             /* for sched_setaffinity */
  31
  32 #include <arpa/inet.h>
  33 #include <errno.h>
  34 #include <fcntl.h>
  35 #include <linux/unistd.h>       /* for __NR_bpf */
  36 #include <linux/filter.h>
  37 #include <linux/bpf.h>
  38 #include <linux/if_packet.h>
  39 #include <net/if.h>
  40 #include <net/ethernet.h>
  41 #include <netinet/ip.h>
  42 #include <netinet/udp.h>
  43 #include <poll.h>
  44 #include <sched.h>
  45 #include <stdint.h>
  46 #include <stdio.h>
  47 #include <stdlib.h>
  48 #include <string.h>
  49 #include <sys/mman.h>
  50 #include <sys/socket.h>
  51 #include <sys/stat.h>
  52 #include <sys/types.h>
  53 #include <unistd.h>
  54
  55 #include "psock_lib.h"
  56
  57 #define RING_NUM_FRAMES                 20
  58
  59 static uint32_t cfg_max_num_members;
  60
  61 /* Open a socket in a given fanout mode.
  62  * @return -1 if mode is bad, a valid socket otherwise */
  63 static int sock_fanout_open(uint16_t typeflags, uint16_t group_id)
  64 {
  65         struct sockaddr_ll addr = {0};
  66         struct fanout_args args;
  67         int fd, val, err;
  68
  69         fd = socket(PF_PACKET, SOCK_RAW, 0);
  70         if (fd < 0) {
  71                 perror("socket packet");
  72                 exit(1);
  73         }
  74
  75         pair_udp_setfilter(fd);
  76
  77         addr.sll_family = AF_PACKET;
  78         addr.sll_protocol = htons(ETH_P_IP);
  79         addr.sll_ifindex = if_nametoindex("lo");
  80         if (addr.sll_ifindex == 0) {
  81                 perror("if_nametoindex");
  82                 exit(1);
  83         }
  84         if (bind(fd, (void *) &addr, sizeof(addr))) {
  85                 perror("bind packet");
  86                 exit(1);
  87         }
  88
  89         if (cfg_max_num_members) {
  90                 args.id = group_id;
  91                 args.type_flags = typeflags;
  92                 args.max_num_members = cfg_max_num_members;
  93                 err = setsockopt(fd, SOL_PACKET, PACKET_FANOUT, &args,
  94                                  sizeof(args));
  95         } else {
  96                 val = (((int) typeflags) << 16) | group_id;
  97                 err = setsockopt(fd, SOL_PACKET, PACKET_FANOUT, &val,
  98                                  sizeof(val));
  99         }
 100         if (err) {
 101                 if (close(fd)) {
 102                         perror("close packet");
 103                         exit(1);
 104                 }
 105                 return -1;
 106         }
 107
 108         return fd;
 109 }
 110
 111 static void sock_fanout_set_cbpf(int fd)
 112 {
 113         struct sock_filter bpf_filter[] = {
 114                 BPF_STMT(BPF_LD+BPF_B+BPF_ABS, 80),           /* ldb [80] */
 115                 BPF_STMT(BPF_RET+BPF_A, 0),                   /* ret A */
 116         };
 117         struct sock_fprog bpf_prog;
 118
 119         bpf_prog.filter = bpf_filter;
 120         bpf_prog.len = sizeof(bpf_filter) / sizeof(struct sock_filter);
 121
 122         if (setsockopt(fd, SOL_PACKET, PACKET_FANOUT_DATA, &bpf_prog,
 123                        sizeof(bpf_prog))) {
 124                 perror("fanout data cbpf");
 125                 exit(1);
 126         }
 127 }
 128
 129 static void sock_fanout_getopts(int fd, uint16_t *typeflags, uint16_t *group_id)
 130 {
 131         int sockopt;
 132         socklen_t sockopt_len = sizeof(sockopt);
 133
 134         if (getsockopt(fd, SOL_PACKET, PACKET_FANOUT,
 135                        &sockopt, &sockopt_len)) {
 136                 perror("failed to getsockopt");
 137                 exit(1);
 138         }
 139         *typeflags = sockopt >> 16;
 140         *group_id = sockopt & 0xfffff;
 141 }
 142
 143 static void sock_fanout_set_ebpf(int fd)
 144 {
 145         static char log_buf[65536];
 146
 147         const int len_off = __builtin_offsetof(struct __sk_buff, len);
 148         struct bpf_insn prog[] = {
 149                 { BPF_ALU64 | BPF_MOV | BPF_X,   6, 1, 0, 0 },
 150                 { BPF_LDX   | BPF_W   | BPF_MEM, 0, 6, len_off, 0 },
 151                 { BPF_JMP   | BPF_JGE | BPF_K,   0, 0, 1, DATA_LEN },
 152                 { BPF_JMP   | BPF_JA  | BPF_K,   0, 0, 4, 0 },
 153                 { BPF_LD    | BPF_B   | BPF_ABS, 0, 0, 0, 0x50 },
 154                 { BPF_JMP   | BPF_JEQ | BPF_K,   0, 0, 2, DATA_CHAR },
 155                 { BPF_JMP   | BPF_JEQ | BPF_K,   0, 0, 1, DATA_CHAR_1 },
 156                 { BPF_ALU   | BPF_MOV | BPF_K,   0, 0, 0, 0 },
 157                 { BPF_JMP   | BPF_EXIT,          0, 0, 0, 0 }
 158         };
 159         union bpf_attr attr;
 160         int pfd;
 161
 162         memset(&attr, 0, sizeof(attr));
 163         attr.prog_type = BPF_PROG_TYPE_SOCKET_FILTER;
 164         attr.insns = (unsigned long) prog;
 165         attr.insn_cnt = sizeof(prog) / sizeof(prog[0]);
 166         attr.license = (unsigned long) "GPL";
 167         attr.log_buf = (unsigned long) log_buf,
 168         attr.log_size = sizeof(log_buf),
 169         attr.log_level = 1,
 170
 171         pfd = syscall(__NR_bpf, BPF_PROG_LOAD, &attr, sizeof(attr));
 172         if (pfd < 0) {
 173                 perror("bpf");
 174                 fprintf(stderr, "bpf verifier:\n%s\n", log_buf);
 175                 exit(1);
 176         }
 177
 178         if (setsockopt(fd, SOL_PACKET, PACKET_FANOUT_DATA, &pfd, sizeof(pfd))) {
 179                 perror("fanout data ebpf");
 180                 exit(1);
 181         }
 182
 183         if (close(pfd)) {
 184                 perror("close ebpf");
 185                 exit(1);
 186         }
 187 }
 188
 189 static char *sock_fanout_open_ring(int fd)
 190 {
 191         struct tpacket_req req = {
 192                 .tp_block_size = getpagesize(),
 193                 .tp_frame_size = getpagesize(),
 194                 .tp_block_nr   = RING_NUM_FRAMES,
 195                 .tp_frame_nr   = RING_NUM_FRAMES,
 196         };
 197         char *ring;
 198         int val = TPACKET_V2;
 199
 200         if (setsockopt(fd, SOL_PACKET, PACKET_VERSION, (void *) &val,
 201                        sizeof(val))) {
 202                 perror("packetsock ring setsockopt version");
 203                 exit(1);
 204         }
 205         if (setsockopt(fd, SOL_PACKET, PACKET_RX_RING, (void *) &req,
 206                        sizeof(req))) {
 207                 perror("packetsock ring setsockopt");
 208                 exit(1);
 209         }
 210
 211         ring = mmap(0, req.tp_block_size * req.tp_block_nr,
 212                     PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0);
 213         if (ring == MAP_FAILED) {
 214                 perror("packetsock ring mmap");
 215                 exit(1);
 216         }
 217
 218         return ring;
 219 }
 220
 221 static int sock_fanout_read_ring(int fd, void *ring)
 222 {
 223         struct tpacket2_hdr *header = ring;
 224         int count = 0;
 225
 226         while (count < RING_NUM_FRAMES && header->tp_status & TP_STATUS_USER) {
 227                 count++;
 228                 header = ring + (count * getpagesize());
 229         }
 230
 231         return count;
 232 }
 233
 234 static int sock_fanout_read(int fds[], char *rings[], const int expect[])
 235 {
 236         int ret[2];
 237
 238         ret[0] = sock_fanout_read_ring(fds[0], rings[0]);
 239         ret[1] = sock_fanout_read_ring(fds[1], rings[1]);
 240
 241         fprintf(stderr, "info: count=%d,%d, expect=%d,%d\n",
 242                         ret[0], ret[1], expect[0], expect[1]);
 243
 244         if ((!(ret[0] == expect[0] && ret[1] == expect[1])) &&
 245             (!(ret[0] == expect[1] && ret[1] == expect[0]))) {
 246                 fprintf(stderr, "warning: incorrect queue lengths\n");
 247                 return 1;
 248         }
 249
 250         return 0;
 251 }
 252
 253 /* Test illegal mode + flag combination */
 254 static void test_control_single(void)
 255 {
 256         fprintf(stderr, "test: control single socket\n");
 257
 258         if (sock_fanout_open(PACKET_FANOUT_ROLLOVER |
 259                                PACKET_FANOUT_FLAG_ROLLOVER, 0) != -1) {
 260                 fprintf(stderr, "ERROR: opened socket with dual rollover\n");
 261                 exit(1);
 262         }
 263 }
 264
 265 /* Test illegal group with different modes or flags */
 266 static void test_control_group(void)
 267 {
 268         int fds[2];
 269
 270         fprintf(stderr, "test: control multiple sockets\n");
 271
 272         fds[0] = sock_fanout_open(PACKET_FANOUT_HASH, 0);
 273         if (fds[0] == -1) {
 274                 fprintf(stderr, "ERROR: failed to open HASH socket\n");
 275                 exit(1);
 276         }
 277         if (sock_fanout_open(PACKET_FANOUT_HASH |
 278                                PACKET_FANOUT_FLAG_DEFRAG, 0) != -1) {
 279                 fprintf(stderr, "ERROR: joined group with wrong flag defrag\n");
 280                 exit(1);
 281         }
 282         if (sock_fanout_open(PACKET_FANOUT_HASH |
 283                                PACKET_FANOUT_FLAG_ROLLOVER, 0) != -1) {
 284                 fprintf(stderr, "ERROR: joined group with wrong flag ro\n");
 285                 exit(1);
 286         }
 287         if (sock_fanout_open(PACKET_FANOUT_CPU, 0) != -1) {
 288                 fprintf(stderr, "ERROR: joined group with wrong mode\n");
 289                 exit(1);
 290         }
 291         fds[1] = sock_fanout_open(PACKET_FANOUT_HASH, 0);
 292         if (fds[1] == -1) {
 293                 fprintf(stderr, "ERROR: failed to join group\n");
 294                 exit(1);
 295         }
 296         if (close(fds[1]) || close(fds[0])) {
 297                 fprintf(stderr, "ERROR: closing sockets\n");
 298                 exit(1);
 299         }
 300 }
 301
 302 /* Test illegal max_num_members values */
 303 static void test_control_group_max_num_members(void)
 304 {
 305         int fds[3];
 306
 307         fprintf(stderr, "test: control multiple sockets, max_num_members\n");
 308
 309         /* expected failure on greater than PACKET_FANOUT_MAX */
 310         cfg_max_num_members = (1 << 16) + 1;
 311         if (sock_fanout_open(PACKET_FANOUT_HASH, 0) != -1) {
 312                 fprintf(stderr, "ERROR: max_num_members > PACKET_FANOUT_MAX\n");
 313                 exit(1);
 314         }
 315
 316         cfg_max_num_members = 256;
 317         fds[0] = sock_fanout_open(PACKET_FANOUT_HASH, 0);
 318         if (fds[0] == -1) {
 319                 fprintf(stderr, "ERROR: failed open\n");
 320                 exit(1);
 321         }
 322
 323         /* expected failure on joining group with different max_num_members */
 324         cfg_max_num_members = 257;
 325         if (sock_fanout_open(PACKET_FANOUT_HASH, 0) != -1) {
 326                 fprintf(stderr, "ERROR: set different max_num_members\n");
 327                 exit(1);
 328         }
 329
 330         /* success on joining group with same max_num_members */
 331         cfg_max_num_members = 256;
 332         fds[1] = sock_fanout_open(PACKET_FANOUT_HASH, 0);
 333         if (fds[1] == -1) {
 334                 fprintf(stderr, "ERROR: failed to join group\n");
 335                 exit(1);
 336         }
 337
 338         /* success on joining group with max_num_members unspecified */
 339         cfg_max_num_members = 0;
 340         fds[2] = sock_fanout_open(PACKET_FANOUT_HASH, 0);
 341         if (fds[2] == -1) {
 342                 fprintf(stderr, "ERROR: failed to join group\n");
 343                 exit(1);
 344         }
 345
 346         if (close(fds[2]) || close(fds[1]) || close(fds[0])) {
 347                 fprintf(stderr, "ERROR: closing sockets\n");
 348                 exit(1);
 349         }
 350 }
 351
 352 /* Test creating a unique fanout group ids */
 353 static void test_unique_fanout_group_ids(void)
 354 {
 355         int fds[3];
 356         uint16_t typeflags, first_group_id, second_group_id;
 357
 358         fprintf(stderr, "test: unique ids\n");
 359
 360         fds[0] = sock_fanout_open(PACKET_FANOUT_HASH |
 361                                   PACKET_FANOUT_FLAG_UNIQUEID, 0);
 362         if (fds[0] == -1) {
 363                 fprintf(stderr, "ERROR: failed to create a unique id group.\n");
 364                 exit(1);
 365         }
 366
 367         sock_fanout_getopts(fds[0], &typeflags, &first_group_id);
 368         if (typeflags != PACKET_FANOUT_HASH) {
 369                 fprintf(stderr, "ERROR: unexpected typeflags %x\n", typeflags);
 370                 exit(1);
 371         }
 372
 373         if (sock_fanout_open(PACKET_FANOUT_CPU, first_group_id) != -1) {
 374                 fprintf(stderr, "ERROR: joined group with wrong type.\n");
 375                 exit(1);
 376         }
 377
 378         fds[1] = sock_fanout_open(PACKET_FANOUT_HASH, first_group_id);
 379         if (fds[1] == -1) {
 380                 fprintf(stderr,
 381                         "ERROR: failed to join previously created group.\n");
 382                 exit(1);
 383         }
 384
 385         fds[2] = sock_fanout_open(PACKET_FANOUT_HASH |
 386                                   PACKET_FANOUT_FLAG_UNIQUEID, 0);
 387         if (fds[2] == -1) {
 388                 fprintf(stderr,
 389                         "ERROR: failed to create a second unique id group.\n");
 390                 exit(1);
 391         }
 392
 393         sock_fanout_getopts(fds[2], &typeflags, &second_group_id);
 394         if (sock_fanout_open(PACKET_FANOUT_HASH | PACKET_FANOUT_FLAG_UNIQUEID,
 395                              second_group_id) != -1) {
 396                 fprintf(stderr,
 397                         "ERROR: specified a group id when requesting unique id\n");
 398                 exit(1);
 399         }
 400
 401         if (close(fds[0]) || close(fds[1]) || close(fds[2])) {
 402                 fprintf(stderr, "ERROR: closing sockets\n");
 403                 exit(1);
 404         }
 405 }
 406
 407 static int test_datapath(uint16_t typeflags, int port_off,
 408                          const int expect1[], const int expect2[])
 409 {
 410         const int expect0[] = { 0, 0 };
 411         char *rings[2];
 412         uint8_t type = typeflags & 0xFF;
 413         int fds[2], fds_udp[2][2], ret;
 414
 415         fprintf(stderr, "\ntest: datapath 0x%hx ports %hu,%hu\n",
 416                 typeflags, (uint16_t)PORT_BASE,
 417                 (uint16_t)(PORT_BASE + port_off));
 418
 419         fds[0] = sock_fanout_open(typeflags, 0);
 420         fds[1] = sock_fanout_open(typeflags, 0);
 421         if (fds[0] == -1 || fds[1] == -1) {
 422                 fprintf(stderr, "ERROR: failed open\n");
 423                 exit(1);
 424         }
 425         if (type == PACKET_FANOUT_CBPF)
 426                 sock_fanout_set_cbpf(fds[0]);
 427         else if (type == PACKET_FANOUT_EBPF)
 428                 sock_fanout_set_ebpf(fds[0]);
 429
 430         rings[0] = sock_fanout_open_ring(fds[0]);
 431         rings[1] = sock_fanout_open_ring(fds[1]);
 432         pair_udp_open(fds_udp[0], PORT_BASE);
 433         pair_udp_open(fds_udp[1], PORT_BASE + port_off);
 434         sock_fanout_read(fds, rings, expect0);
 435
 436         /* Send data, but not enough to overflow a queue */
 437         pair_udp_send(fds_udp[0], 15);
 438         pair_udp_send_char(fds_udp[1], 5, DATA_CHAR_1);
 439         ret = sock_fanout_read(fds, rings, expect1);
 440
 441         /* Send more data, overflow the queue */
 442         pair_udp_send_char(fds_udp[0], 15, DATA_CHAR_1);
 443         /* TODO: ensure consistent order between expect1 and expect2 */
 444         ret |= sock_fanout_read(fds, rings, expect2);
 445
 446         if (munmap(rings[1], RING_NUM_FRAMES * getpagesize()) ||
 447             munmap(rings[0], RING_NUM_FRAMES * getpagesize())) {
 448                 fprintf(stderr, "close rings\n");
 449                 exit(1);
 450         }
 451         if (close(fds_udp[1][1]) || close(fds_udp[1][0]) ||
 452             close(fds_udp[0][1]) || close(fds_udp[0][0]) ||
 453             close(fds[1]) || close(fds[0])) {
 454                 fprintf(stderr, "close datapath\n");
 455                 exit(1);
 456         }
 457
 458         return ret;
 459 }
 460
 461 static int set_cpuaffinity(int cpuid)
 462 {
 463         cpu_set_t mask;
 464
 465         CPU_ZERO(&mask);
 466         CPU_SET(cpuid, &mask);
 467         if (sched_setaffinity(0, sizeof(mask), &mask)) {
 468                 if (errno != EINVAL) {
 469                         fprintf(stderr, "setaffinity %d\n", cpuid);
 470                         exit(1);
 471                 }
 472                 return 1;
 473         }
 474
 475         return 0;
 476 }
 477
 478 int main(int argc, char **argv)
 479 {
 480         const int expect_hash[2][2]     = { { 15, 5 },  { 20, 5 } };
 481         const int expect_hash_rb[2][2]  = { { 15, 5 },  { 20, 15 } };
 482         const int expect_lb[2][2]       = { { 10, 10 }, { 18, 17 } };
 483         const int expect_rb[2][2]       = { { 15, 5 },  { 20, 15 } };
 484         const int expect_cpu0[2][2]     = { { 20, 0 },  { 20, 0 } };
 485         const int expect_cpu1[2][2]     = { { 0, 20 },  { 0, 20 } };
 486         const int expect_bpf[2][2]      = { { 15, 5 },  { 15, 20 } };
 487         const int expect_uniqueid[2][2] = { { 20, 20},  { 20, 20 } };
 488         int port_off = 2, tries = 20, ret;
 489
 490         test_control_single();
 491         test_control_group();
 492         test_control_group_max_num_members();
 493         test_unique_fanout_group_ids();
 494
 495         /* PACKET_FANOUT_MAX */
 496         cfg_max_num_members = 1 << 16;
 497         /* find a set of ports that do not collide onto the same socket */
 498         ret = test_datapath(PACKET_FANOUT_HASH, port_off,
 499                             expect_hash[0], expect_hash[1]);
 500         while (ret) {
 501                 fprintf(stderr, "info: trying alternate ports (%d)\n", tries);
 502                 ret = test_datapath(PACKET_FANOUT_HASH, ++port_off,
 503                                     expect_hash[0], expect_hash[1]);
 504                 if (!--tries) {
 505                         fprintf(stderr, "too many collisions\n");
 506                         return 1;
 507                 }
 508         }
 509
 510         ret |= test_datapath(PACKET_FANOUT_HASH | PACKET_FANOUT_FLAG_ROLLOVER,
 511                              port_off, expect_hash_rb[0], expect_hash_rb[1]);
 512         ret |= test_datapath(PACKET_FANOUT_LB,
 513                              port_off, expect_lb[0], expect_lb[1]);
 514         ret |= test_datapath(PACKET_FANOUT_ROLLOVER,
 515                              port_off, expect_rb[0], expect_rb[1]);
 516
 517         ret |= test_datapath(PACKET_FANOUT_CBPF,
 518                              port_off, expect_bpf[0], expect_bpf[1]);
 519         ret |= test_datapath(PACKET_FANOUT_EBPF,
 520                              port_off, expect_bpf[0], expect_bpf[1]);
 521
 522         set_cpuaffinity(0);
 523         ret |= test_datapath(PACKET_FANOUT_CPU, port_off,
 524                              expect_cpu0[0], expect_cpu0[1]);
 525         if (!set_cpuaffinity(1))
 526                 /* TODO: test that choice alternates with previous */
 527                 ret |= test_datapath(PACKET_FANOUT_CPU, port_off,
 528                                      expect_cpu1[0], expect_cpu1[1]);
 529
 530         ret |= test_datapath(PACKET_FANOUT_FLAG_UNIQUEID, port_off,
 531                              expect_uniqueid[0], expect_uniqueid[1]);
 532
 533         if (ret)
 534                 return 1;
 535
 536         printf("OK. All tests passed\n");
 537         return 0;
 538 }