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/ethernet.h>
  54 #include <netinet/ip.h>
  55 #include <netinet/udp.h>
  56 #include <poll.h>
  57 #include <sched.h>
  58 #include <stdint.h>
  59 #include <stdio.h>
  60 #include <stdlib.h>
  61 #include <string.h>
  62 #include <sys/mman.h>
  63 #include <sys/socket.h>
  64 #include <sys/stat.h>
  65 #include <sys/types.h>
  66 #include <unistd.h>
  67
  68 #include "psock_lib.h"
  69
  70 #define RING_NUM_FRAMES                 20
  71
  72 /* Open a socket in a given fanout mode.
  73  * @return -1 if mode is bad, a valid socket otherwise */
  74 static int sock_fanout_open(uint16_t typeflags, uint16_t group_id)
  75 {
  76         int fd, val;
  77
  78         fd = socket(PF_PACKET, SOCK_RAW, htons(ETH_P_IP));
  79         if (fd < 0) {
  80                 perror("socket packet");
  81                 exit(1);
  82         }
  83
  84         val = (((int) typeflags) << 16) | group_id;
  85         if (setsockopt(fd, SOL_PACKET, PACKET_FANOUT, &val, sizeof(val))) {
  86                 if (close(fd)) {
  87                         perror("close packet");
  88                         exit(1);
  89                 }
  90                 return -1;
  91         }
  92
  93         pair_udp_setfilter(fd);
  94         return fd;
  95 }
  96
  97 static void sock_fanout_set_cbpf(int fd)
  98 {
  99         struct sock_filter bpf_filter[] = {
 100                 BPF_STMT(BPF_LD+BPF_B+BPF_ABS, 80),           /* ldb [80] */
 101                 BPF_STMT(BPF_RET+BPF_A, 0),                   /* ret A */
 102         };
 103         struct sock_fprog bpf_prog;
 104
 105         bpf_prog.filter = bpf_filter;
 106         bpf_prog.len = sizeof(bpf_filter) / sizeof(struct sock_filter);
 107
 108         if (setsockopt(fd, SOL_PACKET, PACKET_FANOUT_DATA, &bpf_prog,
 109                        sizeof(bpf_prog))) {
 110                 perror("fanout data cbpf");
 111                 exit(1);
 112         }
 113 }
 114
 115 static void sock_fanout_getopts(int fd, uint16_t *typeflags, uint16_t *group_id)
 116 {
 117         int sockopt;
 118         socklen_t sockopt_len = sizeof(sockopt);
 119
 120         if (getsockopt(fd, SOL_PACKET, PACKET_FANOUT,
 121                        &sockopt, &sockopt_len)) {
 122                 perror("failed to getsockopt");
 123                 exit(1);
 124         }
 125         *typeflags = sockopt >> 16;
 126         *group_id = sockopt & 0xfffff;
 127 }
 128
 129 static void sock_fanout_set_ebpf(int fd)
 130 {
 131         const int len_off = __builtin_offsetof(struct __sk_buff, len);
 132         struct bpf_insn prog[] = {
 133                 { BPF_ALU64 | BPF_MOV | BPF_X,   6, 1, 0, 0 },
 134                 { BPF_LDX   | BPF_W   | BPF_MEM, 0, 6, len_off, 0 },
 135                 { BPF_JMP   | BPF_JGE | BPF_K,   0, 0, 1, DATA_LEN },
 136                 { BPF_JMP   | BPF_JA  | BPF_K,   0, 0, 4, 0 },
 137                 { BPF_LD    | BPF_B   | BPF_ABS, 0, 0, 0, 0x50 },
 138                 { BPF_JMP   | BPF_JEQ | BPF_K,   0, 0, 2, DATA_CHAR },
 139                 { BPF_JMP   | BPF_JEQ | BPF_K,   0, 0, 1, DATA_CHAR_1 },
 140                 { BPF_ALU   | BPF_MOV | BPF_K,   0, 0, 0, 0 },
 141                 { BPF_JMP   | BPF_EXIT,          0, 0, 0, 0 }
 142         };
 143         char log_buf[512];
 144         union bpf_attr attr;
 145         int pfd;
 146
 147         memset(&attr, 0, sizeof(attr));
 148         attr.prog_type = BPF_PROG_TYPE_SOCKET_FILTER;
 149         attr.insns = (unsigned long) prog;
 150         attr.insn_cnt = sizeof(prog) / sizeof(prog[0]);
 151         attr.license = (unsigned long) "GPL";
 152         attr.log_buf = (unsigned long) log_buf,
 153         attr.log_size = sizeof(log_buf),
 154         attr.log_level = 1,
 155
 156         pfd = syscall(__NR_bpf, BPF_PROG_LOAD, &attr, sizeof(attr));
 157         if (pfd < 0) {
 158                 perror("bpf");
 159                 fprintf(stderr, "bpf verifier:\n%s\n", log_buf);
 160                 exit(1);
 161         }
 162
 163         if (setsockopt(fd, SOL_PACKET, PACKET_FANOUT_DATA, &pfd, sizeof(pfd))) {
 164                 perror("fanout data ebpf");
 165                 exit(1);
 166         }
 167
 168         if (close(pfd)) {
 169                 perror("close ebpf");
 170                 exit(1);
 171         }
 172 }
 173
 174 static char *sock_fanout_open_ring(int fd)
 175 {
 176         struct tpacket_req req = {
 177                 .tp_block_size = getpagesize(),
 178                 .tp_frame_size = getpagesize(),
 179                 .tp_block_nr   = RING_NUM_FRAMES,
 180                 .tp_frame_nr   = RING_NUM_FRAMES,
 181         };
 182         char *ring;
 183         int val = TPACKET_V2;
 184
 185         if (setsockopt(fd, SOL_PACKET, PACKET_VERSION, (void *) &val,
 186                        sizeof(val))) {
 187                 perror("packetsock ring setsockopt version");
 188                 exit(1);
 189         }
 190         if (setsockopt(fd, SOL_PACKET, PACKET_RX_RING, (void *) &req,
 191                        sizeof(req))) {
 192                 perror("packetsock ring setsockopt");
 193                 exit(1);
 194         }
 195
 196         ring = mmap(0, req.tp_block_size * req.tp_block_nr,
 197                     PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0);
 198         if (ring == MAP_FAILED) {
 199                 perror("packetsock ring mmap");
 200                 exit(1);
 201         }
 202
 203         return ring;
 204 }
 205
 206 static int sock_fanout_read_ring(int fd, void *ring)
 207 {
 208         struct tpacket2_hdr *header = ring;
 209         int count = 0;
 210
 211         while (count < RING_NUM_FRAMES && header->tp_status & TP_STATUS_USER) {
 212                 count++;
 213                 header = ring + (count * getpagesize());
 214         }
 215
 216         return count;
 217 }
 218
 219 static int sock_fanout_read(int fds[], char *rings[], const int expect[])
 220 {
 221         int ret[2];
 222
 223         ret[0] = sock_fanout_read_ring(fds[0], rings[0]);
 224         ret[1] = sock_fanout_read_ring(fds[1], rings[1]);
 225
 226         fprintf(stderr, "info: count=%d,%d, expect=%d,%d\n",
 227                         ret[0], ret[1], expect[0], expect[1]);
 228
 229         if ((!(ret[0] == expect[0] && ret[1] == expect[1])) &&
 230             (!(ret[0] == expect[1] && ret[1] == expect[0]))) {
 231                 fprintf(stderr, "ERROR: incorrect queue lengths\n");
 232                 return 1;
 233         }
 234
 235         return 0;
 236 }
 237
 238 /* Test illegal mode + flag combination */
 239 static void test_control_single(void)
 240 {
 241         fprintf(stderr, "test: control single socket\n");
 242
 243         if (sock_fanout_open(PACKET_FANOUT_ROLLOVER |
 244                                PACKET_FANOUT_FLAG_ROLLOVER, 0) != -1) {
 245                 fprintf(stderr, "ERROR: opened socket with dual rollover\n");
 246                 exit(1);
 247         }
 248 }
 249
 250 /* Test illegal group with different modes or flags */
 251 static void test_control_group(void)
 252 {
 253         int fds[2];
 254
 255         fprintf(stderr, "test: control multiple sockets\n");
 256
 257         fds[0] = sock_fanout_open(PACKET_FANOUT_HASH, 0);
 258         if (fds[0] == -1) {
 259                 fprintf(stderr, "ERROR: failed to open HASH socket\n");
 260                 exit(1);
 261         }
 262         if (sock_fanout_open(PACKET_FANOUT_HASH |
 263                                PACKET_FANOUT_FLAG_DEFRAG, 0) != -1) {
 264                 fprintf(stderr, "ERROR: joined group with wrong flag defrag\n");
 265                 exit(1);
 266         }
 267         if (sock_fanout_open(PACKET_FANOUT_HASH |
 268                                PACKET_FANOUT_FLAG_ROLLOVER, 0) != -1) {
 269                 fprintf(stderr, "ERROR: joined group with wrong flag ro\n");
 270                 exit(1);
 271         }
 272         if (sock_fanout_open(PACKET_FANOUT_CPU, 0) != -1) {
 273                 fprintf(stderr, "ERROR: joined group with wrong mode\n");
 274                 exit(1);
 275         }
 276         fds[1] = sock_fanout_open(PACKET_FANOUT_HASH, 0);
 277         if (fds[1] == -1) {
 278                 fprintf(stderr, "ERROR: failed to join group\n");
 279                 exit(1);
 280         }
 281         if (close(fds[1]) || close(fds[0])) {
 282                 fprintf(stderr, "ERROR: closing sockets\n");
 283                 exit(1);
 284         }
 285 }
 286
 287 /* Test creating a unique fanout group ids */
 288 static void test_unique_fanout_group_ids(void)
 289 {
 290         int fds[3];
 291         uint16_t typeflags, first_group_id, second_group_id;
 292
 293         fprintf(stderr, "test: unique ids\n");
 294
 295         fds[0] = sock_fanout_open(PACKET_FANOUT_HASH |
 296                                   PACKET_FANOUT_FLAG_UNIQUEID, 0);
 297         if (fds[0] == -1) {
 298                 fprintf(stderr, "ERROR: failed to create a unique id group.\n");
 299                 exit(1);
 300         }
 301
 302         sock_fanout_getopts(fds[0], &typeflags, &first_group_id);
 303         if (typeflags != PACKET_FANOUT_HASH) {
 304                 fprintf(stderr, "ERROR: unexpected typeflags %x\n", typeflags);
 305                 exit(1);
 306         }
 307
 308         if (sock_fanout_open(PACKET_FANOUT_CPU, first_group_id) != -1) {
 309                 fprintf(stderr, "ERROR: joined group with wrong type.\n");
 310                 exit(1);
 311         }
 312
 313         fds[1] = sock_fanout_open(PACKET_FANOUT_HASH, first_group_id);
 314         if (fds[1] == -1) {
 315                 fprintf(stderr,
 316                         "ERROR: failed to join previously created group.\n");
 317                 exit(1);
 318         }
 319
 320         fds[2] = sock_fanout_open(PACKET_FANOUT_HASH |
 321                                   PACKET_FANOUT_FLAG_UNIQUEID, 0);
 322         if (fds[2] == -1) {
 323                 fprintf(stderr,
 324                         "ERROR: failed to create a second unique id group.\n");
 325                 exit(1);
 326         }
 327
 328         sock_fanout_getopts(fds[2], &typeflags, &second_group_id);
 329         if (sock_fanout_open(PACKET_FANOUT_HASH | PACKET_FANOUT_FLAG_UNIQUEID,
 330                              second_group_id) != -1) {
 331                 fprintf(stderr,
 332                         "ERROR: specified a group id when requesting unique id\n");
 333                 exit(1);
 334         }
 335
 336         if (close(fds[0]) || close(fds[1]) || close(fds[2])) {
 337                 fprintf(stderr, "ERROR: closing sockets\n");
 338                 exit(1);
 339         }
 340 }
 341
 342 static int test_datapath(uint16_t typeflags, int port_off,
 343                          const int expect1[], const int expect2[])
 344 {
 345         const int expect0[] = { 0, 0 };
 346         char *rings[2];
 347         uint8_t type = typeflags & 0xFF;
 348         int fds[2], fds_udp[2][2], ret;
 349
 350         fprintf(stderr, "test: datapath 0x%hx\n", typeflags);
 351
 352         fds[0] = sock_fanout_open(typeflags, 0);
 353         fds[1] = sock_fanout_open(typeflags, 0);
 354         if (fds[0] == -1 || fds[1] == -1) {
 355                 fprintf(stderr, "ERROR: failed open\n");
 356                 exit(1);
 357         }
 358         if (type == PACKET_FANOUT_CBPF)
 359                 sock_fanout_set_cbpf(fds[0]);
 360         else if (type == PACKET_FANOUT_EBPF)
 361                 sock_fanout_set_ebpf(fds[0]);
 362
 363         rings[0] = sock_fanout_open_ring(fds[0]);
 364         rings[1] = sock_fanout_open_ring(fds[1]);
 365         pair_udp_open(fds_udp[0], PORT_BASE);
 366         pair_udp_open(fds_udp[1], PORT_BASE + port_off);
 367         sock_fanout_read(fds, rings, expect0);
 368
 369         /* Send data, but not enough to overflow a queue */
 370         pair_udp_send(fds_udp[0], 15);
 371         pair_udp_send_char(fds_udp[1], 5, DATA_CHAR_1);
 372         ret = sock_fanout_read(fds, rings, expect1);
 373
 374         /* Send more data, overflow the queue */
 375         pair_udp_send_char(fds_udp[0], 15, DATA_CHAR_1);
 376         /* TODO: ensure consistent order between expect1 and expect2 */
 377         ret |= sock_fanout_read(fds, rings, expect2);
 378
 379         if (munmap(rings[1], RING_NUM_FRAMES * getpagesize()) ||
 380             munmap(rings[0], RING_NUM_FRAMES * getpagesize())) {
 381                 fprintf(stderr, "close rings\n");
 382                 exit(1);
 383         }
 384         if (close(fds_udp[1][1]) || close(fds_udp[1][0]) ||
 385             close(fds_udp[0][1]) || close(fds_udp[0][0]) ||
 386             close(fds[1]) || close(fds[0])) {
 387                 fprintf(stderr, "close datapath\n");
 388                 exit(1);
 389         }
 390
 391         return ret;
 392 }
 393
 394 static int set_cpuaffinity(int cpuid)
 395 {
 396         cpu_set_t mask;
 397
 398         CPU_ZERO(&mask);
 399         CPU_SET(cpuid, &mask);
 400         if (sched_setaffinity(0, sizeof(mask), &mask)) {
 401                 if (errno != EINVAL) {
 402                         fprintf(stderr, "setaffinity %d\n", cpuid);
 403                         exit(1);
 404                 }
 405                 return 1;
 406         }
 407
 408         return 0;
 409 }
 410
 411 int main(int argc, char **argv)
 412 {
 413         const int expect_hash[2][2]     = { { 15, 5 },  { 20, 5 } };
 414         const int expect_hash_rb[2][2]  = { { 15, 5 },  { 20, 15 } };
 415         const int expect_lb[2][2]       = { { 10, 10 }, { 18, 17 } };
 416         const int expect_rb[2][2]       = { { 15, 5 },  { 20, 15 } };
 417         const int expect_cpu0[2][2]     = { { 20, 0 },  { 20, 0 } };
 418         const int expect_cpu1[2][2]     = { { 0, 20 },  { 0, 20 } };
 419         const int expect_bpf[2][2]      = { { 15, 5 },  { 15, 20 } };
 420         const int expect_uniqueid[2][2] = { { 20, 20},  { 20, 20 } };
 421         int port_off = 2, tries = 5, ret;
 422
 423         test_control_single();
 424         test_control_group();
 425         test_unique_fanout_group_ids();
 426
 427         /* find a set of ports that do not collide onto the same socket */
 428         ret = test_datapath(PACKET_FANOUT_HASH, port_off,
 429                             expect_hash[0], expect_hash[1]);
 430         while (ret && tries--) {
 431                 fprintf(stderr, "info: trying alternate ports (%d)\n", tries);
 432                 ret = test_datapath(PACKET_FANOUT_HASH, ++port_off,
 433                                     expect_hash[0], expect_hash[1]);
 434         }
 435
 436         ret |= test_datapath(PACKET_FANOUT_HASH | PACKET_FANOUT_FLAG_ROLLOVER,
 437                              port_off, expect_hash_rb[0], expect_hash_rb[1]);
 438         ret |= test_datapath(PACKET_FANOUT_LB,
 439                              port_off, expect_lb[0], expect_lb[1]);
 440         ret |= test_datapath(PACKET_FANOUT_ROLLOVER,
 441                              port_off, expect_rb[0], expect_rb[1]);
 442
 443         ret |= test_datapath(PACKET_FANOUT_CBPF,
 444                              port_off, expect_bpf[0], expect_bpf[1]);
 445         ret |= test_datapath(PACKET_FANOUT_EBPF,
 446                              port_off, expect_bpf[0], expect_bpf[1]);
 447
 448         set_cpuaffinity(0);
 449         ret |= test_datapath(PACKET_FANOUT_CPU, port_off,
 450                              expect_cpu0[0], expect_cpu0[1]);
 451         if (!set_cpuaffinity(1))
 452                 /* TODO: test that choice alternates with previous */
 453                 ret |= test_datapath(PACKET_FANOUT_CPU, port_off,
 454                                      expect_cpu1[0], expect_cpu1[1]);
 455
 456         ret |= test_datapath(PACKET_FANOUT_FLAG_UNIQUEID, port_off,
 457                              expect_uniqueid[0], expect_uniqueid[1]);
 458
 459         if (ret)
 460                 return 1;
 461
 462         printf("OK. All tests passed\n");
 463         return 0;
 464 }