linux/tools/testing/selftests/net/psock_fanout.c
<<
>>
Prefs
   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 */
  75static 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
 112static 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
 130static 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
 144static 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
 190static 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
 222static 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
 235static 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 */
 255static 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 */
 267static 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 */
 304static 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
 358static 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
 411static 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
 428int 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}
 486