tools/testing/selftests/net/psock_fanout.c

   1 /*
   2  * Copyright 2013 Google Inc.
   3  * Author: Willem de Bruijn (willemb@google.com)
   4  *
   5  * A basic test of packet socket fanout behavior.
   6  *
   7  * Control:
   8  * - create fanout fails as expected with illegal flag combinations
   9  * - join   fanout fails as expected with diverging types or flags
  10  *
  11  * Datapath:
  12  *   Open a pair of packet sockets and a pair of INET sockets, send a known
  13  *   number of packets across the two INET sockets and count the number of
  14  *   packets enqueued onto the two packet sockets.
  15  *
  16  *   The test currently runs for
  17  *   - PACKET_FANOUT_HASH
  18  *   - PACKET_FANOUT_HASH with PACKET_FANOUT_FLAG_ROLLOVER
  19  *   - PACKET_FANOUT_LB
  20  *   - PACKET_FANOUT_CPU
  21  *   - PACKET_FANOUT_ROLLOVER
  22  *   - PACKET_FANOUT_CBPF
  23  *   - PACKET_FANOUT_EBPF
  24  *
  25  * Todo:
  26  * - functionality: PACKET_FANOUT_FLAG_DEFRAG
  27  *
  28  * License (GPLv2):
  29  *
  30  * This program is free software; you can redistribute it and/or modify it
  31  * under the terms and conditions of the GNU General Public License,
  32  * version 2, as published by the Free Software Foundation.
  33  *
  34  * This program is distributed in the hope it will be useful, but WITHOUT
  35  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  36  * FITNESS FOR A PARTICULAR PURPOSE. * See the GNU General Public License for
  37  * more details.
  38  *
  39  * You should have received a copy of the GNU General Public License along with
  40  * this program; if not, write to the Free Software Foundation, Inc.,
  41  * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
  42  */
  43
  44 #define _GNU_SOURCE             /* for sched_setaffinity */
  45
  46 #include <arpa/inet.h>
  47 #include <errno.h>
  48 #include <fcntl.h>
  49 #include <linux/unistd.h>       /* for __NR_bpf */
  50 #include <linux/filter.h>
  51 #include <linux/bpf.h>
  52 #include <linux/if_packet.h>
  53 #include <net/if.h>
  54 #include <net/ethernet.h>
  55 #include <netinet/ip.h>
  56 #include <netinet/udp.h>
  57 #include <poll.h>
  58 #include <sched.h>
  59 #include <stdint.h>
  60 #include <stdio.h>
  61 #include <stdlib.h>
  62 #include <string.h>
  63 #include <sys/mman.h>
  64 #include <sys/socket.h>
  65 #include <sys/stat.h>
  66 #include <sys/types.h>
  67 #include <unistd.h>
  68
  69 #include "psock_lib.h"
  70
  71 #define RING_NUM_FRAMES                 20
  72
  73 /* Open a socket in a given fanout mode.
  74  * @return -1 if mode is bad, a valid socket otherwise */
  75 static int sock_fanout_open(uint16_t typeflags, uint16_t group_id)
  76 {
  77         struct sockaddr_ll addr = {0};
  78         int fd, val;
  79
  80         fd = socket(PF_PACKET, SOCK_RAW, 0);
  81         if (fd < 0) {
  82                 perror("socket packet");
  83                 exit(1);
  84         }
  85
  86         pair_udp_setfilter(fd);
  87
  88         addr.sll_family = AF_PACKET;
  89         addr.sll_protocol = htons(ETH_P_IP);
  90         addr.sll_ifindex = if_nametoindex("lo");
  91         if (addr.sll_ifindex == 0) {
  92                 perror("if_nametoindex");
  93                 exit(1);
  94         }
  95         if (bind(fd, (void *) &addr, sizeof(addr))) {
  96                 perror("bind packet");
  97                 exit(1);
  98         }
  99
 100         val = (((int) typeflags) << 16) | group_id;
 101         if (setsockopt(fd, SOL_PACKET, PACKET_FANOUT, &val, sizeof(val))) {
 102                 if (close(fd)) {
 103                         perror("close packet");
 104                         exit(1);
 105                 }
 106                 return -1;
 107         }
 108
 109         return fd;
 110 }
 111
 112 static void sock_fanout_set_cbpf(int fd)
 113 {
 114         struct sock_filter bpf_filter[] = {
 115                 BPF_STMT(BPF_LD+BPF_B+BPF_ABS, 80),           /* ldb [80] */
 116                 BPF_STMT(BPF_RET+BPF_A, 0),                   /* ret A */
 117         };
 118         struct sock_fprog bpf_prog;
 119
 120         bpf_prog.filter = bpf_filter;
 121         bpf_prog.len = sizeof(bpf_filter) / sizeof(struct sock_filter);
 122
 123         if (setsockopt(fd, SOL_PACKET, PACKET_FANOUT_DATA, &bpf_prog,
 124                        sizeof(bpf_prog))) {
 125                 perror("fanout data cbpf");
 126                 exit(1);
 127         }
 128 }
 129
 130 static void sock_fanout_getopts(int fd, uint16_t *typeflags, uint16_t *group_id)
 131 {
 132         int sockopt;
 133         socklen_t sockopt_len = sizeof(sockopt);
 134
 135         if (getsockopt(fd, SOL_PACKET, PACKET_FANOUT,
 136                        &sockopt, &sockopt_len)) {
 137                 perror("failed to getsockopt");
 138                 exit(1);
 139         }
 140         *typeflags = sockopt >> 16;
 141         *group_id = sockopt & 0xfffff;
 142 }
 143
 144 static void sock_fanout_set_ebpf(int fd)
 145 {
 146         static char log_buf[65536];
 147
 148         const int len_off = __builtin_offsetof(struct __sk_buff, len);
 149         struct bpf_insn prog[] = {
 150                 { BPF_ALU64 | BPF_MOV | BPF_X,   6, 1, 0, 0 },
 151                 { BPF_LDX   | BPF_W   | BPF_MEM, 0, 6, len_off, 0 },
 152                 { BPF_JMP   | BPF_JGE | BPF_K,   0, 0, 1, DATA_LEN },
 153                 { BPF_JMP   | BPF_JA  | BPF_K,   0, 0, 4, 0 },
 154                 { BPF_LD    | BPF_B   | BPF_ABS, 0, 0, 0, 0x50 },
 155                 { BPF_JMP   | BPF_JEQ | BPF_K,   0, 0, 2, DATA_CHAR },
 156                 { BPF_JMP   | BPF_JEQ | BPF_K,   0, 0, 1, DATA_CHAR_1 },
 157                 { BPF_ALU   | BPF_MOV | BPF_K,   0, 0, 0, 0 },
 158                 { BPF_JMP   | BPF_EXIT,          0, 0, 0, 0 }
 159         };
 160         union bpf_attr attr;
 161         int pfd;
 162
 163         memset(&attr, 0, sizeof(attr));
 164         attr.prog_type = BPF_PROG_TYPE_SOCKET_FILTER;
 165         attr.insns = (unsigned long) prog;
 166         attr.insn_cnt = sizeof(prog) / sizeof(prog[0]);
 167         attr.license = (unsigned long) "GPL";
 168         attr.log_buf = (unsigned long) log_buf,
 169         attr.log_size = sizeof(log_buf),
 170         attr.log_level = 1,
 171
 172         pfd = syscall(__NR_bpf, BPF_PROG_LOAD, &attr, sizeof(attr));
 173         if (pfd < 0) {
 174                 perror("bpf");
 175                 fprintf(stderr, "bpf verifier:\n%s\n", log_buf);
 176                 exit(1);
 177         }
 178
 179         if (setsockopt(fd, SOL_PACKET, PACKET_FANOUT_DATA, &pfd, sizeof(pfd))) {
 180                 perror("fanout data ebpf");
 181                 exit(1);
 182         }
 183
 184         if (close(pfd)) {
 185                 perror("close ebpf");
 186                 exit(1);
 187         }
 188 }
 189
 190 static char *sock_fanout_open_ring(int fd)
 191 {
 192         struct tpacket_req req = {
 193                 .tp_block_size = getpagesize(),
 194                 .tp_frame_size = getpagesize(),
 195                 .tp_block_nr   = RING_NUM_FRAMES,
 196                 .tp_frame_nr   = RING_NUM_FRAMES,
 197         };
 198         char *ring;
 199         int val = TPACKET_V2;
 200
 201         if (setsockopt(fd, SOL_PACKET, PACKET_VERSION, (void *) &val,
 202                        sizeof(val))) {
 203                 perror("packetsock ring setsockopt version");
 204                 exit(1);
 205         }
 206         if (setsockopt(fd, SOL_PACKET, PACKET_RX_RING, (void *) &req,
 207                        sizeof(req))) {
 208                 perror("packetsock ring setsockopt");
 209                 exit(1);
 210         }
 211
 212         ring = mmap(0, req.tp_block_size * req.tp_block_nr,
 213                     PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0);
 214         if (ring == MAP_FAILED) {
 215                 perror("packetsock ring mmap");
 216                 exit(1);
 217         }
 218
 219         return ring;
 220 }
 221
 222 static int sock_fanout_read_ring(int fd, void *ring)
 223 {
 224         struct tpacket2_hdr *header = ring;
 225         int count = 0;
 226
 227         while (count < RING_NUM_FRAMES && header->tp_status & TP_STATUS_USER) {
 228                 count++;
 229                 header = ring + (count * getpagesize());
 230         }
 231
 232         return count;
 233 }
 234
 235 static int sock_fanout_read(int fds[], char *rings[], const int expect[])
 236 {
 237         int ret[2];
 238
 239         ret[0] = sock_fanout_read_ring(fds[0], rings[0]);
 240         ret[1] = sock_fanout_read_ring(fds[1], rings[1]);
 241
 242         fprintf(stderr, "info: count=%d,%d, expect=%d,%d\n",
 243                         ret[0], ret[1], expect[0], expect[1]);
 244
 245         if ((!(ret[0] == expect[0] && ret[1] == expect[1])) &&
 246             (!(ret[0] == expect[1] && ret[1] == expect[0]))) {
 247                 fprintf(stderr, "warning: incorrect queue lengths\n");
 248                 return 1;
 249         }
 250
 251         return 0;
 252 }
 253
 254 /* Test illegal mode + flag combination */
 255 static void test_control_single(void)
 256 {
 257         fprintf(stderr, "test: control single socket\n");
 258
 259         if (sock_fanout_open(PACKET_FANOUT_ROLLOVER |
 260                                PACKET_FANOUT_FLAG_ROLLOVER, 0) != -1) {
 261                 fprintf(stderr, "ERROR: opened socket with dual rollover\n");
 262                 exit(1);
 263         }
 264 }
 265
 266 /* Test illegal group with different modes or flags */
 267 static void test_control_group(void)
 268 {
 269         int fds[2];
 270
 271         fprintf(stderr, "test: control multiple sockets\n");
 272
 273         fds[0] = sock_fanout_open(PACKET_FANOUT_HASH, 0);
 274         if (fds[0] == -1) {
 275                 fprintf(stderr, "ERROR: failed to open HASH socket\n");
 276                 exit(1);
 277         }
 278         if (sock_fanout_open(PACKET_FANOUT_HASH |
 279                                PACKET_FANOUT_FLAG_DEFRAG, 0) != -1) {
 280                 fprintf(stderr, "ERROR: joined group with wrong flag defrag\n");
 281                 exit(1);
 282         }
 283         if (sock_fanout_open(PACKET_FANOUT_HASH |
 284                                PACKET_FANOUT_FLAG_ROLLOVER, 0) != -1) {
 285                 fprintf(stderr, "ERROR: joined group with wrong flag ro\n");
 286                 exit(1);
 287         }
 288         if (sock_fanout_open(PACKET_FANOUT_CPU, 0) != -1) {
 289                 fprintf(stderr, "ERROR: joined group with wrong mode\n");
 290                 exit(1);
 291         }
 292         fds[1] = sock_fanout_open(PACKET_FANOUT_HASH, 0);
 293         if (fds[1] == -1) {
 294                 fprintf(stderr, "ERROR: failed to join group\n");
 295                 exit(1);
 296         }
 297         if (close(fds[1]) || close(fds[0])) {
 298                 fprintf(stderr, "ERROR: closing sockets\n");
 299                 exit(1);
 300         }
 301 }
 302
 303 /* Test creating a unique fanout group ids */
 304 static void test_unique_fanout_group_ids(void)
 305 {
 306         int fds[3];
 307         uint16_t typeflags, first_group_id, second_group_id;
 308
 309         fprintf(stderr, "test: unique ids\n");
 310
 311         fds[0] = sock_fanout_open(PACKET_FANOUT_HASH |
 312                                   PACKET_FANOUT_FLAG_UNIQUEID, 0);
 313         if (fds[0] == -1) {
 314                 fprintf(stderr, "ERROR: failed to create a unique id group.\n");
 315                 exit(1);
 316         }
 317
 318         sock_fanout_getopts(fds[0], &typeflags, &first_group_id);
 319         if (typeflags != PACKET_FANOUT_HASH) {
 320                 fprintf(stderr, "ERROR: unexpected typeflags %x\n", typeflags);
 321                 exit(1);
 322         }
 323
 324         if (sock_fanout_open(PACKET_FANOUT_CPU, first_group_id) != -1) {
 325                 fprintf(stderr, "ERROR: joined group with wrong type.\n");
 326                 exit(1);
 327         }
 328
 329         fds[1] = sock_fanout_open(PACKET_FANOUT_HASH, first_group_id);
 330         if (fds[1] == -1) {
 331                 fprintf(stderr,
 332                         "ERROR: failed to join previously created group.\n");
 333                 exit(1);
 334         }
 335
 336         fds[2] = sock_fanout_open(PACKET_FANOUT_HASH |
 337                                   PACKET_FANOUT_FLAG_UNIQUEID, 0);
 338         if (fds[2] == -1) {
 339                 fprintf(stderr,
 340                         "ERROR: failed to create a second unique id group.\n");
 341                 exit(1);
 342         }
 343
 344         sock_fanout_getopts(fds[2], &typeflags, &second_group_id);
 345         if (sock_fanout_open(PACKET_FANOUT_HASH | PACKET_FANOUT_FLAG_UNIQUEID,
 346                              second_group_id) != -1) {
 347                 fprintf(stderr,
 348                         "ERROR: specified a group id when requesting unique id\n");
 349                 exit(1);
 350         }
 351
 352         if (close(fds[0]) || close(fds[1]) || close(fds[2])) {
 353                 fprintf(stderr, "ERROR: closing sockets\n");
 354                 exit(1);
 355         }
 356 }
 357
 358 static int test_datapath(uint16_t typeflags, int port_off,
 359                          const int expect1[], const int expect2[])
 360 {
 361         const int expect0[] = { 0, 0 };
 362         char *rings[2];
 363         uint8_t type = typeflags & 0xFF;
 364         int fds[2], fds_udp[2][2], ret;
 365
 366         fprintf(stderr, "\ntest: datapath 0x%hx ports %hu,%hu\n",
 367                 typeflags, PORT_BASE, PORT_BASE + port_off);
 368
 369         fds[0] = sock_fanout_open(typeflags, 0);
 370         fds[1] = sock_fanout_open(typeflags, 0);
 371         if (fds[0] == -1 || fds[1] == -1) {
 372                 fprintf(stderr, "ERROR: failed open\n");
 373                 exit(1);
 374         }
 375         if (type == PACKET_FANOUT_CBPF)
 376                 sock_fanout_set_cbpf(fds[0]);
 377         else if (type == PACKET_FANOUT_EBPF)
 378                 sock_fanout_set_ebpf(fds[0]);
 379
 380         rings[0] = sock_fanout_open_ring(fds[0]);
 381         rings[1] = sock_fanout_open_ring(fds[1]);
 382         pair_udp_open(fds_udp[0], PORT_BASE);
 383         pair_udp_open(fds_udp[1], PORT_BASE + port_off);
 384         sock_fanout_read(fds, rings, expect0);
 385
 386         /* Send data, but not enough to overflow a queue */
 387         pair_udp_send(fds_udp[0], 15);
 388         pair_udp_send_char(fds_udp[1], 5, DATA_CHAR_1);
 389         ret = sock_fanout_read(fds, rings, expect1);
 390
 391         /* Send more data, overflow the queue */
 392         pair_udp_send_char(fds_udp[0], 15, DATA_CHAR_1);
 393         /* TODO: ensure consistent order between expect1 and expect2 */
 394         ret |= sock_fanout_read(fds, rings, expect2);
 395
 396         if (munmap(rings[1], RING_NUM_FRAMES * getpagesize()) ||
 397             munmap(rings[0], RING_NUM_FRAMES * getpagesize())) {
 398                 fprintf(stderr, "close rings\n");
 399                 exit(1);
 400         }
 401         if (close(fds_udp[1][1]) || close(fds_udp[1][0]) ||
 402             close(fds_udp[0][1]) || close(fds_udp[0][0]) ||
 403             close(fds[1]) || close(fds[0])) {
 404                 fprintf(stderr, "close datapath\n");
 405                 exit(1);
 406         }
 407
 408         return ret;
 409 }
 410
 411 static int set_cpuaffinity(int cpuid)
 412 {
 413         cpu_set_t mask;
 414
 415         CPU_ZERO(&mask);
 416         CPU_SET(cpuid, &mask);
 417         if (sched_setaffinity(0, sizeof(mask), &mask)) {
 418                 if (errno != EINVAL) {
 419                         fprintf(stderr, "setaffinity %d\n", cpuid);
 420                         exit(1);
 421                 }
 422                 return 1;
 423         }
 424
 425         return 0;
 426 }
 427
 428 int main(int argc, char **argv)
 429 {
 430         const int expect_hash[2][2]     = { { 15, 5 },  { 20, 5 } };
 431         const int expect_hash_rb[2][2]  = { { 15, 5 },  { 20, 15 } };
 432         const int expect_lb[2][2]       = { { 10, 10 }, { 18, 17 } };
 433         const int expect_rb[2][2]       = { { 15, 5 },  { 20, 15 } };
 434         const int expect_cpu0[2][2]     = { { 20, 0 },  { 20, 0 } };
 435         const int expect_cpu1[2][2]     = { { 0, 20 },  { 0, 20 } };
 436         const int expect_bpf[2][2]      = { { 15, 5 },  { 15, 20 } };
 437         const int expect_uniqueid[2][2] = { { 20, 20},  { 20, 20 } };
 438         int port_off = 2, tries = 20, ret;
 439
 440         test_control_single();
 441         test_control_group();
 442         test_unique_fanout_group_ids();
 443
 444         /* find a set of ports that do not collide onto the same socket */
 445         ret = test_datapath(PACKET_FANOUT_HASH, port_off,
 446                             expect_hash[0], expect_hash[1]);
 447         while (ret) {
 448                 fprintf(stderr, "info: trying alternate ports (%d)\n", tries);
 449                 ret = test_datapath(PACKET_FANOUT_HASH, ++port_off,
 450                                     expect_hash[0], expect_hash[1]);
 451                 if (!--tries) {
 452                         fprintf(stderr, "too many collisions\n");
 453                         return 1;
 454                 }
 455         }
 456
 457         ret |= test_datapath(PACKET_FANOUT_HASH | PACKET_FANOUT_FLAG_ROLLOVER,
 458                              port_off, expect_hash_rb[0], expect_hash_rb[1]);
 459         ret |= test_datapath(PACKET_FANOUT_LB,
 460                              port_off, expect_lb[0], expect_lb[1]);
 461         ret |= test_datapath(PACKET_FANOUT_ROLLOVER,
 462                              port_off, expect_rb[0], expect_rb[1]);
 463
 464         ret |= test_datapath(PACKET_FANOUT_CBPF,
 465                              port_off, expect_bpf[0], expect_bpf[1]);
 466         ret |= test_datapath(PACKET_FANOUT_EBPF,
 467                              port_off, expect_bpf[0], expect_bpf[1]);
 468
 469         set_cpuaffinity(0);
 470         ret |= test_datapath(PACKET_FANOUT_CPU, port_off,
 471                              expect_cpu0[0], expect_cpu0[1]);
 472         if (!set_cpuaffinity(1))
 473                 /* TODO: test that choice alternates with previous */
 474                 ret |= test_datapath(PACKET_FANOUT_CPU, port_off,
 475                                      expect_cpu1[0], expect_cpu1[1]);
 476
 477         ret |= test_datapath(PACKET_FANOUT_FLAG_UNIQUEID, port_off,
 478                              expect_uniqueid[0], expect_uniqueid[1]);
 479
 480         if (ret)
 481                 return 1;
 482
 483         printf("OK. All tests passed\n");
 484         return 0;
 485 }