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, int num_packets)
  75 {
  76         int fd, val;
  77
  78         fd = socket(PF_PACKET, SOCK_DGRAM, htons(ETH_P_IP));
  79         if (fd < 0) {
  80                 perror("socket packet");
  81                 exit(1);
  82         }
  83
  84         /* fanout group ID is always 0: tests whether old groups are deleted */
  85         val = ((int) typeflags) << 16;
  86         if (setsockopt(fd, SOL_PACKET, PACKET_FANOUT, &val, sizeof(val))) {
  87                 if (close(fd)) {
  88                         perror("close packet");
  89                         exit(1);
  90                 }
  91                 return -1;
  92         }
  93
  94         pair_udp_setfilter(fd);
  95         return fd;
  96 }
  97
  98 static void sock_fanout_set_ebpf(int fd)
  99 {
 100         const int len_off = __builtin_offsetof(struct __sk_buff, len);
 101         struct bpf_insn prog[] = {
 102                 { BPF_ALU64 | BPF_MOV | BPF_X,   6, 1, 0, 0 },
 103                 { BPF_LDX   | BPF_W   | BPF_MEM, 0, 6, len_off, 0 },
 104                 { BPF_JMP   | BPF_JGE | BPF_K,   0, 0, 1, DATA_LEN },
 105                 { BPF_JMP   | BPF_JA  | BPF_K,   0, 0, 4, 0 },
 106                 { BPF_LD    | BPF_B   | BPF_ABS, 0, 0, 0, 0x50 },
 107                 { BPF_JMP   | BPF_JEQ | BPF_K,   0, 0, 2, DATA_CHAR },
 108                 { BPF_JMP   | BPF_JEQ | BPF_K,   0, 0, 1, DATA_CHAR_1 },
 109                 { BPF_ALU   | BPF_MOV | BPF_K,   0, 0, 0, 0 },
 110                 { BPF_JMP   | BPF_EXIT,          0, 0, 0, 0 }
 111         };
 112         char log_buf[512];
 113         union bpf_attr attr;
 114         int pfd;
 115
 116         memset(&attr, 0, sizeof(attr));
 117         attr.prog_type = BPF_PROG_TYPE_SOCKET_FILTER;
 118         attr.insns = (unsigned long) prog;
 119         attr.insn_cnt = sizeof(prog) / sizeof(prog[0]);
 120         attr.license = (unsigned long) "GPL";
 121         attr.log_buf = (unsigned long) log_buf,
 122         attr.log_size = sizeof(log_buf),
 123         attr.log_level = 1,
 124
 125         pfd = syscall(__NR_bpf, BPF_PROG_LOAD, &attr, sizeof(attr));
 126         if (pfd < 0) {
 127                 perror("bpf");
 128                 fprintf(stderr, "bpf verifier:\n%s\n", log_buf);
 129                 exit(1);
 130         }
 131
 132         if (setsockopt(fd, SOL_PACKET, PACKET_FANOUT_DATA, &pfd, sizeof(pfd))) {
 133                 perror("fanout data ebpf");
 134                 exit(1);
 135         }
 136
 137         if (close(pfd)) {
 138                 perror("close ebpf");
 139                 exit(1);
 140         }
 141 }
 142
 143 static char *sock_fanout_open_ring(int fd)
 144 {
 145         struct tpacket_req req = {
 146                 .tp_block_size = getpagesize(),
 147                 .tp_frame_size = getpagesize(),
 148                 .tp_block_nr   = RING_NUM_FRAMES,
 149                 .tp_frame_nr   = RING_NUM_FRAMES,
 150         };
 151         char *ring;
 152         int val = TPACKET_V2;
 153
 154         if (setsockopt(fd, SOL_PACKET, PACKET_VERSION, (void *) &val,
 155                        sizeof(val))) {
 156                 perror("packetsock ring setsockopt version");
 157                 exit(1);
 158         }
 159         if (setsockopt(fd, SOL_PACKET, PACKET_RX_RING, (void *) &req,
 160                        sizeof(req))) {
 161                 perror("packetsock ring setsockopt");
 162                 exit(1);
 163         }
 164
 165         ring = mmap(0, req.tp_block_size * req.tp_block_nr,
 166                     PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0);
 167         if (ring == MAP_FAILED) {
 168                 perror("packetsock ring mmap");
 169                 exit(1);
 170         }
 171
 172         return ring;
 173 }
 174
 175 static int sock_fanout_read_ring(int fd, void *ring)
 176 {
 177         struct tpacket2_hdr *header = ring;
 178         int count = 0;
 179
 180         while (count < RING_NUM_FRAMES && header->tp_status & TP_STATUS_USER) {
 181                 count++;
 182                 header = ring + (count * getpagesize());
 183         }
 184
 185         return count;
 186 }
 187
 188 static int sock_fanout_read(int fds[], char *rings[], const int expect[])
 189 {
 190         int ret[2];
 191
 192         ret[0] = sock_fanout_read_ring(fds[0], rings[0]);
 193         ret[1] = sock_fanout_read_ring(fds[1], rings[1]);
 194
 195         fprintf(stderr, "info: count=%d,%d, expect=%d,%d\n",
 196                         ret[0], ret[1], expect[0], expect[1]);
 197
 198         if ((!(ret[0] == expect[0] && ret[1] == expect[1])) &&
 199             (!(ret[0] == expect[1] && ret[1] == expect[0]))) {
 200                 fprintf(stderr, "ERROR: incorrect queue lengths\n");
 201                 return 1;
 202         }
 203
 204         return 0;
 205 }
 206
 207 /* Test illegal mode + flag combination */
 208 static void test_control_single(void)
 209 {
 210         fprintf(stderr, "test: control single socket\n");
 211
 212         if (sock_fanout_open(PACKET_FANOUT_ROLLOVER |
 213                                PACKET_FANOUT_FLAG_ROLLOVER, 0) != -1) {
 214                 fprintf(stderr, "ERROR: opened socket with dual rollover\n");
 215                 exit(1);
 216         }
 217 }
 218
 219 /* Test illegal group with different modes or flags */
 220 static void test_control_group(void)
 221 {
 222         int fds[2];
 223
 224         fprintf(stderr, "test: control multiple sockets\n");
 225
 226         fds[0] = sock_fanout_open(PACKET_FANOUT_HASH, 20);
 227         if (fds[0] == -1) {
 228                 fprintf(stderr, "ERROR: failed to open HASH socket\n");
 229                 exit(1);
 230         }
 231         if (sock_fanout_open(PACKET_FANOUT_HASH |
 232                                PACKET_FANOUT_FLAG_DEFRAG, 10) != -1) {
 233                 fprintf(stderr, "ERROR: joined group with wrong flag defrag\n");
 234                 exit(1);
 235         }
 236         if (sock_fanout_open(PACKET_FANOUT_HASH |
 237                                PACKET_FANOUT_FLAG_ROLLOVER, 10) != -1) {
 238                 fprintf(stderr, "ERROR: joined group with wrong flag ro\n");
 239                 exit(1);
 240         }
 241         if (sock_fanout_open(PACKET_FANOUT_CPU, 10) != -1) {
 242                 fprintf(stderr, "ERROR: joined group with wrong mode\n");
 243                 exit(1);
 244         }
 245         fds[1] = sock_fanout_open(PACKET_FANOUT_HASH, 20);
 246         if (fds[1] == -1) {
 247                 fprintf(stderr, "ERROR: failed to join group\n");
 248                 exit(1);
 249         }
 250         if (close(fds[1]) || close(fds[0])) {
 251                 fprintf(stderr, "ERROR: closing sockets\n");
 252                 exit(1);
 253         }
 254 }
 255
 256 static int test_datapath(uint16_t typeflags, int port_off,
 257                          const int expect1[], const int expect2[])
 258 {
 259         const int expect0[] = { 0, 0 };
 260         char *rings[2];
 261         uint8_t type = typeflags & 0xFF;
 262         int fds[2], fds_udp[2][2], ret;
 263
 264         fprintf(stderr, "test: datapath 0x%hx\n", typeflags);
 265
 266         fds[0] = sock_fanout_open(typeflags, 20);
 267         fds[1] = sock_fanout_open(typeflags, 20);
 268         if (fds[0] == -1 || fds[1] == -1) {
 269                 fprintf(stderr, "ERROR: failed open\n");
 270                 exit(1);
 271         }
 272         if (type == PACKET_FANOUT_CBPF)
 273                 sock_setfilter(fds[0], SOL_PACKET, PACKET_FANOUT_DATA);
 274         else if (type == PACKET_FANOUT_EBPF)
 275                 sock_fanout_set_ebpf(fds[0]);
 276
 277         rings[0] = sock_fanout_open_ring(fds[0]);
 278         rings[1] = sock_fanout_open_ring(fds[1]);
 279         pair_udp_open(fds_udp[0], PORT_BASE);
 280         pair_udp_open(fds_udp[1], PORT_BASE + port_off);
 281         sock_fanout_read(fds, rings, expect0);
 282
 283         /* Send data, but not enough to overflow a queue */
 284         pair_udp_send(fds_udp[0], 15);
 285         pair_udp_send_char(fds_udp[1], 5, DATA_CHAR_1);
 286         ret = sock_fanout_read(fds, rings, expect1);
 287
 288         /* Send more data, overflow the queue */
 289         pair_udp_send_char(fds_udp[0], 15, DATA_CHAR_1);
 290         /* TODO: ensure consistent order between expect1 and expect2 */
 291         ret |= sock_fanout_read(fds, rings, expect2);
 292
 293         if (munmap(rings[1], RING_NUM_FRAMES * getpagesize()) ||
 294             munmap(rings[0], RING_NUM_FRAMES * getpagesize())) {
 295                 fprintf(stderr, "close rings\n");
 296                 exit(1);
 297         }
 298         if (close(fds_udp[1][1]) || close(fds_udp[1][0]) ||
 299             close(fds_udp[0][1]) || close(fds_udp[0][0]) ||
 300             close(fds[1]) || close(fds[0])) {
 301                 fprintf(stderr, "close datapath\n");
 302                 exit(1);
 303         }
 304
 305         return ret;
 306 }
 307
 308 static int set_cpuaffinity(int cpuid)
 309 {
 310         cpu_set_t mask;
 311
 312         CPU_ZERO(&mask);
 313         CPU_SET(cpuid, &mask);
 314         if (sched_setaffinity(0, sizeof(mask), &mask)) {
 315                 if (errno != EINVAL) {
 316                         fprintf(stderr, "setaffinity %d\n", cpuid);
 317                         exit(1);
 318                 }
 319                 return 1;
 320         }
 321
 322         return 0;
 323 }
 324
 325 int main(int argc, char **argv)
 326 {
 327         const int expect_hash[2][2]     = { { 15, 5 },  { 20, 5 } };
 328         const int expect_hash_rb[2][2]  = { { 15, 5 },  { 20, 15 } };
 329         const int expect_lb[2][2]       = { { 10, 10 }, { 18, 17 } };
 330         const int expect_rb[2][2]       = { { 15, 5 },  { 20, 15 } };
 331         const int expect_cpu0[2][2]     = { { 20, 0 },  { 20, 0 } };
 332         const int expect_cpu1[2][2]     = { { 0, 20 },  { 0, 20 } };
 333         const int expect_bpf[2][2]      = { { 15, 5 },  { 15, 20 } };
 334         int port_off = 2, tries = 5, ret;
 335
 336         test_control_single();
 337         test_control_group();
 338
 339         /* find a set of ports that do not collide onto the same socket */
 340         ret = test_datapath(PACKET_FANOUT_HASH, port_off,
 341                             expect_hash[0], expect_hash[1]);
 342         while (ret && tries--) {
 343                 fprintf(stderr, "info: trying alternate ports (%d)\n", tries);
 344                 ret = test_datapath(PACKET_FANOUT_HASH, ++port_off,
 345                                     expect_hash[0], expect_hash[1]);
 346         }
 347
 348         ret |= test_datapath(PACKET_FANOUT_HASH | PACKET_FANOUT_FLAG_ROLLOVER,
 349                              port_off, expect_hash_rb[0], expect_hash_rb[1]);
 350         ret |= test_datapath(PACKET_FANOUT_LB,
 351                              port_off, expect_lb[0], expect_lb[1]);
 352         ret |= test_datapath(PACKET_FANOUT_ROLLOVER,
 353                              port_off, expect_rb[0], expect_rb[1]);
 354
 355         ret |= test_datapath(PACKET_FANOUT_CBPF,
 356                              port_off, expect_bpf[0], expect_bpf[1]);
 357         ret |= test_datapath(PACKET_FANOUT_EBPF,
 358                              port_off, expect_bpf[0], expect_bpf[1]);
 359
 360         set_cpuaffinity(0);
 361         ret |= test_datapath(PACKET_FANOUT_CPU, port_off,
 362                              expect_cpu0[0], expect_cpu0[1]);
 363         if (!set_cpuaffinity(1))
 364                 /* TODO: test that choice alternates with previous */
 365                 ret |= test_datapath(PACKET_FANOUT_CPU, port_off,
 366                                      expect_cpu1[0], expect_cpu1[1]);
 367
 368         if (ret)
 369                 return 1;
 370
 371         printf("OK. All tests passed\n");
 372         return 0;
 373 }