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 /* Open a socket in a given fanout mode.
  60  * @return -1 if mode is bad, a valid socket otherwise */
  61 static int sock_fanout_open(uint16_t typeflags, uint16_t group_id)
  62 {
  63         struct sockaddr_ll addr = {0};
  64         int fd, val;
  65
  66         fd = socket(PF_PACKET, SOCK_RAW, 0);
  67         if (fd < 0) {
  68                 perror("socket packet");
  69                 exit(1);
  70         }
  71
  72         pair_udp_setfilter(fd);
  73
  74         addr.sll_family = AF_PACKET;
  75         addr.sll_protocol = htons(ETH_P_IP);
  76         addr.sll_ifindex = if_nametoindex("lo");
  77         if (addr.sll_ifindex == 0) {
  78                 perror("if_nametoindex");
  79                 exit(1);
  80         }
  81         if (bind(fd, (void *) &addr, sizeof(addr))) {
  82                 perror("bind packet");
  83                 exit(1);
  84         }
  85
  86         val = (((int) typeflags) << 16) | group_id;
  87         if (setsockopt(fd, SOL_PACKET, PACKET_FANOUT, &val, sizeof(val))) {
  88                 if (close(fd)) {
  89                         perror("close packet");
  90                         exit(1);
  91                 }
  92                 return -1;
  93         }
  94
  95         return fd;
  96 }
  97
  98 static void sock_fanout_set_cbpf(int fd)
  99 {
 100         struct sock_filter bpf_filter[] = {
 101                 BPF_STMT(BPF_LD+BPF_B+BPF_ABS, 80),           /* ldb [80] */
 102                 BPF_STMT(BPF_RET+BPF_A, 0),                   /* ret A */
 103         };
 104         struct sock_fprog bpf_prog;
 105
 106         bpf_prog.filter = bpf_filter;
 107         bpf_prog.len = sizeof(bpf_filter) / sizeof(struct sock_filter);
 108
 109         if (setsockopt(fd, SOL_PACKET, PACKET_FANOUT_DATA, &bpf_prog,
 110                        sizeof(bpf_prog))) {
 111                 perror("fanout data cbpf");
 112                 exit(1);
 113         }
 114 }
 115
 116 static void sock_fanout_getopts(int fd, uint16_t *typeflags, uint16_t *group_id)
 117 {
 118         int sockopt;
 119         socklen_t sockopt_len = sizeof(sockopt);
 120
 121         if (getsockopt(fd, SOL_PACKET, PACKET_FANOUT,
 122                        &sockopt, &sockopt_len)) {
 123                 perror("failed to getsockopt");
 124                 exit(1);
 125         }
 126         *typeflags = sockopt >> 16;
 127         *group_id = sockopt & 0xfffff;
 128 }
 129
 130 static void sock_fanout_set_ebpf(int fd)
 131 {
 132         static char log_buf[65536];
 133
 134         const int len_off = __builtin_offsetof(struct __sk_buff, len);
 135         struct bpf_insn prog[] = {
 136                 { BPF_ALU64 | BPF_MOV | BPF_X,   6, 1, 0, 0 },
 137                 { BPF_LDX   | BPF_W   | BPF_MEM, 0, 6, len_off, 0 },
 138                 { BPF_JMP   | BPF_JGE | BPF_K,   0, 0, 1, DATA_LEN },
 139                 { BPF_JMP   | BPF_JA  | BPF_K,   0, 0, 4, 0 },
 140                 { BPF_LD    | BPF_B   | BPF_ABS, 0, 0, 0, 0x50 },
 141                 { BPF_JMP   | BPF_JEQ | BPF_K,   0, 0, 2, DATA_CHAR },
 142                 { BPF_JMP   | BPF_JEQ | BPF_K,   0, 0, 1, DATA_CHAR_1 },
 143                 { BPF_ALU   | BPF_MOV | BPF_K,   0, 0, 0, 0 },
 144                 { BPF_JMP   | BPF_EXIT,          0, 0, 0, 0 }
 145         };
 146         union bpf_attr attr;
 147         int pfd;
 148
 149         memset(&attr, 0, sizeof(attr));
 150         attr.prog_type = BPF_PROG_TYPE_SOCKET_FILTER;
 151         attr.insns = (unsigned long) prog;
 152         attr.insn_cnt = sizeof(prog) / sizeof(prog[0]);
 153         attr.license = (unsigned long) "GPL";
 154         attr.log_buf = (unsigned long) log_buf,
 155         attr.log_size = sizeof(log_buf),
 156         attr.log_level = 1,
 157
 158         pfd = syscall(__NR_bpf, BPF_PROG_LOAD, &attr, sizeof(attr));
 159         if (pfd < 0) {
 160                 perror("bpf");
 161                 fprintf(stderr, "bpf verifier:\n%s\n", log_buf);
 162                 exit(1);
 163         }
 164
 165         if (setsockopt(fd, SOL_PACKET, PACKET_FANOUT_DATA, &pfd, sizeof(pfd))) {
 166                 perror("fanout data ebpf");
 167                 exit(1);
 168         }
 169
 170         if (close(pfd)) {
 171                 perror("close ebpf");
 172                 exit(1);
 173         }
 174 }
 175
 176 static char *sock_fanout_open_ring(int fd)
 177 {
 178         struct tpacket_req req = {
 179                 .tp_block_size = getpagesize(),
 180                 .tp_frame_size = getpagesize(),
 181                 .tp_block_nr   = RING_NUM_FRAMES,
 182                 .tp_frame_nr   = RING_NUM_FRAMES,
 183         };
 184         char *ring;
 185         int val = TPACKET_V2;
 186
 187         if (setsockopt(fd, SOL_PACKET, PACKET_VERSION, (void *) &val,
 188                        sizeof(val))) {
 189                 perror("packetsock ring setsockopt version");
 190                 exit(1);
 191         }
 192         if (setsockopt(fd, SOL_PACKET, PACKET_RX_RING, (void *) &req,
 193                        sizeof(req))) {
 194                 perror("packetsock ring setsockopt");
 195                 exit(1);
 196         }
 197
 198         ring = mmap(0, req.tp_block_size * req.tp_block_nr,
 199                     PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0);
 200         if (ring == MAP_FAILED) {
 201                 perror("packetsock ring mmap");
 202                 exit(1);
 203         }
 204
 205         return ring;
 206 }
 207
 208 static int sock_fanout_read_ring(int fd, void *ring)
 209 {
 210         struct tpacket2_hdr *header = ring;
 211         int count = 0;
 212
 213         while (count < RING_NUM_FRAMES && header->tp_status & TP_STATUS_USER) {
 214                 count++;
 215                 header = ring + (count * getpagesize());
 216         }
 217
 218         return count;
 219 }
 220
 221 static int sock_fanout_read(int fds[], char *rings[], const int expect[])
 222 {
 223         int ret[2];
 224
 225         ret[0] = sock_fanout_read_ring(fds[0], rings[0]);
 226         ret[1] = sock_fanout_read_ring(fds[1], rings[1]);
 227
 228         fprintf(stderr, "info: count=%d,%d, expect=%d,%d\n",
 229                         ret[0], ret[1], expect[0], expect[1]);
 230
 231         if ((!(ret[0] == expect[0] && ret[1] == expect[1])) &&
 232             (!(ret[0] == expect[1] && ret[1] == expect[0]))) {
 233                 fprintf(stderr, "warning: incorrect queue lengths\n");
 234                 return 1;
 235         }
 236
 237         return 0;
 238 }
 239
 240 /* Test illegal mode + flag combination */
 241 static void test_control_single(void)
 242 {
 243         fprintf(stderr, "test: control single socket\n");
 244
 245         if (sock_fanout_open(PACKET_FANOUT_ROLLOVER |
 246                                PACKET_FANOUT_FLAG_ROLLOVER, 0) != -1) {
 247                 fprintf(stderr, "ERROR: opened socket with dual rollover\n");
 248                 exit(1);
 249         }
 250 }
 251
 252 /* Test illegal group with different modes or flags */
 253 static void test_control_group(void)
 254 {
 255         int fds[2];
 256
 257         fprintf(stderr, "test: control multiple sockets\n");
 258
 259         fds[0] = sock_fanout_open(PACKET_FANOUT_HASH, 0);
 260         if (fds[0] == -1) {
 261                 fprintf(stderr, "ERROR: failed to open HASH socket\n");
 262                 exit(1);
 263         }
 264         if (sock_fanout_open(PACKET_FANOUT_HASH |
 265                                PACKET_FANOUT_FLAG_DEFRAG, 0) != -1) {
 266                 fprintf(stderr, "ERROR: joined group with wrong flag defrag\n");
 267                 exit(1);
 268         }
 269         if (sock_fanout_open(PACKET_FANOUT_HASH |
 270                                PACKET_FANOUT_FLAG_ROLLOVER, 0) != -1) {
 271                 fprintf(stderr, "ERROR: joined group with wrong flag ro\n");
 272                 exit(1);
 273         }
 274         if (sock_fanout_open(PACKET_FANOUT_CPU, 0) != -1) {
 275                 fprintf(stderr, "ERROR: joined group with wrong mode\n");
 276                 exit(1);
 277         }
 278         fds[1] = sock_fanout_open(PACKET_FANOUT_HASH, 0);
 279         if (fds[1] == -1) {
 280                 fprintf(stderr, "ERROR: failed to join group\n");
 281                 exit(1);
 282         }
 283         if (close(fds[1]) || close(fds[0])) {
 284                 fprintf(stderr, "ERROR: closing sockets\n");
 285                 exit(1);
 286         }
 287 }
 288
 289 /* Test creating a unique fanout group ids */
 290 static void test_unique_fanout_group_ids(void)
 291 {
 292         int fds[3];
 293         uint16_t typeflags, first_group_id, second_group_id;
 294
 295         fprintf(stderr, "test: unique ids\n");
 296
 297         fds[0] = sock_fanout_open(PACKET_FANOUT_HASH |
 298                                   PACKET_FANOUT_FLAG_UNIQUEID, 0);
 299         if (fds[0] == -1) {
 300                 fprintf(stderr, "ERROR: failed to create a unique id group.\n");
 301                 exit(1);
 302         }
 303
 304         sock_fanout_getopts(fds[0], &typeflags, &first_group_id);
 305         if (typeflags != PACKET_FANOUT_HASH) {
 306                 fprintf(stderr, "ERROR: unexpected typeflags %x\n", typeflags);
 307                 exit(1);
 308         }
 309
 310         if (sock_fanout_open(PACKET_FANOUT_CPU, first_group_id) != -1) {
 311                 fprintf(stderr, "ERROR: joined group with wrong type.\n");
 312                 exit(1);
 313         }
 314
 315         fds[1] = sock_fanout_open(PACKET_FANOUT_HASH, first_group_id);
 316         if (fds[1] == -1) {
 317                 fprintf(stderr,
 318                         "ERROR: failed to join previously created group.\n");
 319                 exit(1);
 320         }
 321
 322         fds[2] = sock_fanout_open(PACKET_FANOUT_HASH |
 323                                   PACKET_FANOUT_FLAG_UNIQUEID, 0);
 324         if (fds[2] == -1) {
 325                 fprintf(stderr,
 326                         "ERROR: failed to create a second unique id group.\n");
 327                 exit(1);
 328         }
 329
 330         sock_fanout_getopts(fds[2], &typeflags, &second_group_id);
 331         if (sock_fanout_open(PACKET_FANOUT_HASH | PACKET_FANOUT_FLAG_UNIQUEID,
 332                              second_group_id) != -1) {
 333                 fprintf(stderr,
 334                         "ERROR: specified a group id when requesting unique id\n");
 335                 exit(1);
 336         }
 337
 338         if (close(fds[0]) || close(fds[1]) || close(fds[2])) {
 339                 fprintf(stderr, "ERROR: closing sockets\n");
 340                 exit(1);
 341         }
 342 }
 343
 344 static int test_datapath(uint16_t typeflags, int port_off,
 345                          const int expect1[], const int expect2[])
 346 {
 347         const int expect0[] = { 0, 0 };
 348         char *rings[2];
 349         uint8_t type = typeflags & 0xFF;
 350         int fds[2], fds_udp[2][2], ret;
 351
 352         fprintf(stderr, "\ntest: datapath 0x%hx ports %hu,%hu\n",
 353                 typeflags, PORT_BASE, PORT_BASE + port_off);
 354
 355         fds[0] = sock_fanout_open(typeflags, 0);
 356         fds[1] = sock_fanout_open(typeflags, 0);
 357         if (fds[0] == -1 || fds[1] == -1) {
 358                 fprintf(stderr, "ERROR: failed open\n");
 359                 exit(1);
 360         }
 361         if (type == PACKET_FANOUT_CBPF)
 362                 sock_fanout_set_cbpf(fds[0]);
 363         else if (type == PACKET_FANOUT_EBPF)
 364                 sock_fanout_set_ebpf(fds[0]);
 365
 366         rings[0] = sock_fanout_open_ring(fds[0]);
 367         rings[1] = sock_fanout_open_ring(fds[1]);
 368         pair_udp_open(fds_udp[0], PORT_BASE);
 369         pair_udp_open(fds_udp[1], PORT_BASE + port_off);
 370         sock_fanout_read(fds, rings, expect0);
 371
 372         /* Send data, but not enough to overflow a queue */
 373         pair_udp_send(fds_udp[0], 15);
 374         pair_udp_send_char(fds_udp[1], 5, DATA_CHAR_1);
 375         ret = sock_fanout_read(fds, rings, expect1);
 376
 377         /* Send more data, overflow the queue */
 378         pair_udp_send_char(fds_udp[0], 15, DATA_CHAR_1);
 379         /* TODO: ensure consistent order between expect1 and expect2 */
 380         ret |= sock_fanout_read(fds, rings, expect2);
 381
 382         if (munmap(rings[1], RING_NUM_FRAMES * getpagesize()) ||
 383             munmap(rings[0], RING_NUM_FRAMES * getpagesize())) {
 384                 fprintf(stderr, "close rings\n");
 385                 exit(1);
 386         }
 387         if (close(fds_udp[1][1]) || close(fds_udp[1][0]) ||
 388             close(fds_udp[0][1]) || close(fds_udp[0][0]) ||
 389             close(fds[1]) || close(fds[0])) {
 390                 fprintf(stderr, "close datapath\n");
 391                 exit(1);
 392         }
 393
 394         return ret;
 395 }
 396
 397 static int set_cpuaffinity(int cpuid)
 398 {
 399         cpu_set_t mask;
 400
 401         CPU_ZERO(&mask);
 402         CPU_SET(cpuid, &mask);
 403         if (sched_setaffinity(0, sizeof(mask), &mask)) {
 404                 if (errno != EINVAL) {
 405                         fprintf(stderr, "setaffinity %d\n", cpuid);
 406                         exit(1);
 407                 }
 408                 return 1;
 409         }
 410
 411         return 0;
 412 }
 413
 414 int main(int argc, char **argv)
 415 {
 416         const int expect_hash[2][2]     = { { 15, 5 },  { 20, 5 } };
 417         const int expect_hash_rb[2][2]  = { { 15, 5 },  { 20, 15 } };
 418         const int expect_lb[2][2]       = { { 10, 10 }, { 18, 17 } };
 419         const int expect_rb[2][2]       = { { 15, 5 },  { 20, 15 } };
 420         const int expect_cpu0[2][2]     = { { 20, 0 },  { 20, 0 } };
 421         const int expect_cpu1[2][2]     = { { 0, 20 },  { 0, 20 } };
 422         const int expect_bpf[2][2]      = { { 15, 5 },  { 15, 20 } };
 423         const int expect_uniqueid[2][2] = { { 20, 20},  { 20, 20 } };
 424         int port_off = 2, tries = 20, ret;
 425
 426         test_control_single();
 427         test_control_group();
 428         test_unique_fanout_group_ids();
 429
 430         /* find a set of ports that do not collide onto the same socket */
 431         ret = test_datapath(PACKET_FANOUT_HASH, port_off,
 432                             expect_hash[0], expect_hash[1]);
 433         while (ret) {
 434                 fprintf(stderr, "info: trying alternate ports (%d)\n", tries);
 435                 ret = test_datapath(PACKET_FANOUT_HASH, ++port_off,
 436                                     expect_hash[0], expect_hash[1]);
 437                 if (!--tries) {
 438                         fprintf(stderr, "too many collisions\n");
 439                         return 1;
 440                 }
 441         }
 442
 443         ret |= test_datapath(PACKET_FANOUT_HASH | PACKET_FANOUT_FLAG_ROLLOVER,
 444                              port_off, expect_hash_rb[0], expect_hash_rb[1]);
 445         ret |= test_datapath(PACKET_FANOUT_LB,
 446                              port_off, expect_lb[0], expect_lb[1]);
 447         ret |= test_datapath(PACKET_FANOUT_ROLLOVER,
 448                              port_off, expect_rb[0], expect_rb[1]);
 449
 450         ret |= test_datapath(PACKET_FANOUT_CBPF,
 451                              port_off, expect_bpf[0], expect_bpf[1]);
 452         ret |= test_datapath(PACKET_FANOUT_EBPF,
 453                              port_off, expect_bpf[0], expect_bpf[1]);
 454
 455         set_cpuaffinity(0);
 456         ret |= test_datapath(PACKET_FANOUT_CPU, port_off,
 457                              expect_cpu0[0], expect_cpu0[1]);
 458         if (!set_cpuaffinity(1))
 459                 /* TODO: test that choice alternates with previous */
 460                 ret |= test_datapath(PACKET_FANOUT_CPU, port_off,
 461                                      expect_cpu1[0], expect_cpu1[1]);
 462
 463         ret |= test_datapath(PACKET_FANOUT_FLAG_UNIQUEID, port_off,
 464                              expect_uniqueid[0], expect_uniqueid[1]);
 465
 466         if (ret)
 467                 return 1;
 468
 469         printf("OK. All tests passed\n");
 470         return 0;
 471 }