tools/testing/selftests/net-afpacket/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_ROLLOVER
  20  *
  21  * Todo:
  22  * - datapath: PACKET_FANOUT_LB
  23  * - datapath: PACKET_FANOUT_CPU
  24  * - functionality: PACKET_FANOUT_FLAG_DEFRAG
  25  *
  26  * License (GPLv2):
  27  *
  28  * This program is free software; you can redistribute it and/or modify it
  29  * under the terms and conditions of the GNU General Public License,
  30  * version 2, as published by the Free Software Foundation.
  31  *
  32  * This program is distributed in the hope it will be useful, but WITHOUT
  33  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  34  * FITNESS FOR A PARTICULAR PURPOSE. * See the GNU General Public License for
  35  * more details.
  36  *
  37  * You should have received a copy of the GNU General Public License along with
  38  * this program; if not, write to the Free Software Foundation, Inc.,
  39  * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
  40  */
  41
  42 #include <arpa/inet.h>
  43 #include <errno.h>
  44 #include <linux/filter.h>
  45 #include <linux/if_packet.h>
  46 #include <net/ethernet.h>
  47 #include <netinet/ip.h>
  48 #include <netinet/udp.h>
  49 #include <fcntl.h>
  50 #include <stdint.h>
  51 #include <stdio.h>
  52 #include <stdlib.h>
  53 #include <string.h>
  54 #include <sys/socket.h>
  55 #include <sys/stat.h>
  56 #include <sys/types.h>
  57 #include <unistd.h>
  58
  59 /* Hack: build even if local includes are old */
  60 #ifndef PACKET_FANOUT
  61 #define PACKET_FANOUT                   18
  62 #define PACKET_FANOUT_HASH              0
  63 #define PACKET_FANOUT_LB                1
  64 #define PACKET_FANOUT_CPU               2
  65 #define PACKET_FANOUT_FLAG_DEFRAG       0x8000
  66
  67 #ifndef PACKET_FANOUT_ROLLOVER
  68 #define PACKET_FANOUT_ROLLOVER          3
  69 #endif
  70
  71 #ifndef PACKET_FANOUT_FLAG_ROLLOVER
  72 #define PACKET_FANOUT_FLAG_ROLLOVER     0x1000
  73 #endif
  74
  75 #endif
  76
  77 #define DATA_LEN                        100
  78 #define DATA_CHAR                       'a'
  79
  80 static void pair_udp_open(int fds[], uint16_t port)
  81 {
  82         struct sockaddr_in saddr, daddr;
  83
  84         fds[0] = socket(PF_INET, SOCK_DGRAM, 0);
  85         fds[1] = socket(PF_INET, SOCK_DGRAM, 0);
  86         if (fds[0] == -1 || fds[1] == -1) {
  87                 fprintf(stderr, "ERROR: socket dgram\n");
  88                 exit(1);
  89         }
  90
  91         memset(&saddr, 0, sizeof(saddr));
  92         saddr.sin_family = AF_INET;
  93         saddr.sin_port = htons(port);
  94         saddr.sin_addr.s_addr = htonl(INADDR_LOOPBACK);
  95
  96         memset(&daddr, 0, sizeof(daddr));
  97         daddr.sin_family = AF_INET;
  98         daddr.sin_port = htons(port + 1);
  99         daddr.sin_addr.s_addr = htonl(INADDR_LOOPBACK);
 100
 101         /* must bind both to get consistent hash result */
 102         if (bind(fds[1], (void *) &daddr, sizeof(daddr))) {
 103                 perror("bind");
 104                 exit(1);
 105         }
 106         if (bind(fds[0], (void *) &saddr, sizeof(saddr))) {
 107                 perror("bind");
 108                 exit(1);
 109         }
 110         if (connect(fds[0], (void *) &daddr, sizeof(daddr))) {
 111                 perror("bind");
 112                 exit(1);
 113         }
 114 }
 115
 116 static void pair_udp_send(int fds[], int num)
 117 {
 118         char buf[DATA_LEN], rbuf[DATA_LEN];
 119
 120         memset(buf, DATA_CHAR, sizeof(buf));
 121         while (num--) {
 122                 /* Should really handle EINTR and EAGAIN */
 123                 if (write(fds[0], buf, sizeof(buf)) != sizeof(buf)) {
 124                         fprintf(stderr, "ERROR: send failed left=%d\n", num);
 125                         exit(1);
 126                 }
 127                 if (read(fds[1], rbuf, sizeof(rbuf)) != sizeof(rbuf)) {
 128                         fprintf(stderr, "ERROR: recv failed left=%d\n", num);
 129                         exit(1);
 130                 }
 131                 if (memcmp(buf, rbuf, sizeof(buf))) {
 132                         fprintf(stderr, "ERROR: data failed left=%d\n", num);
 133                         exit(1);
 134                 }
 135         }
 136 }
 137
 138 static void sock_fanout_setfilter(int fd)
 139 {
 140         struct sock_filter bpf_filter[] = {
 141                 { 0x80, 0, 0, 0x00000000 },  /* LD  pktlen                    */
 142                 { 0x35, 0, 5, DATA_LEN   },  /* JGE DATA_LEN  [f goto nomatch]*/
 143                 { 0x30, 0, 0, 0x00000050 },  /* LD  ip[80]                    */
 144                 { 0x15, 0, 3, DATA_CHAR  },  /* JEQ DATA_CHAR [f goto nomatch]*/
 145                 { 0x30, 0, 0, 0x00000051 },  /* LD  ip[81]                    */
 146                 { 0x15, 0, 1, DATA_CHAR  },  /* JEQ DATA_CHAR [f goto nomatch]*/
 147                 { 0x6, 0, 0, 0x00000060  },  /* RET match                     */
 148 /* nomatch */   { 0x6, 0, 0, 0x00000000  },  /* RET no match                  */
 149         };
 150         struct sock_fprog bpf_prog;
 151
 152         bpf_prog.filter = bpf_filter;
 153         bpf_prog.len = sizeof(bpf_filter) / sizeof(struct sock_filter);
 154         if (setsockopt(fd, SOL_SOCKET, SO_ATTACH_FILTER, &bpf_prog,
 155                        sizeof(bpf_prog))) {
 156                 perror("setsockopt SO_ATTACH_FILTER");
 157                 exit(1);
 158         }
 159 }
 160
 161 /* Open a socket in a given fanout mode.
 162  * @return -1 if mode is bad, a valid socket otherwise */
 163 static int sock_fanout_open(uint16_t typeflags, int num_packets)
 164 {
 165         int fd, val;
 166
 167         fd = socket(PF_PACKET, SOCK_DGRAM, htons(ETH_P_IP));
 168         if (fd < 0) {
 169                 perror("socket packet");
 170                 exit(1);
 171         }
 172
 173         /* fanout group ID is always 0: tests whether old groups are deleted */
 174         val = ((int) typeflags) << 16;
 175         if (setsockopt(fd, SOL_PACKET, PACKET_FANOUT, &val, sizeof(val))) {
 176                 if (close(fd)) {
 177                         perror("close packet");
 178                         exit(1);
 179                 }
 180                 return -1;
 181         }
 182
 183         val = sizeof(struct iphdr) + sizeof(struct udphdr) + DATA_LEN;
 184         val *= num_packets;
 185         /* hack: apparently, the above calculation is too small (TODO: fix) */
 186         val *= 3;
 187         if (setsockopt(fd, SOL_SOCKET, SO_RCVBUF, &val, sizeof(val))) {
 188                 perror("setsockopt SO_RCVBUF");
 189                 exit(1);
 190         }
 191
 192         sock_fanout_setfilter(fd);
 193         return fd;
 194 }
 195
 196 static void sock_fanout_read(int fds[], const int expect[])
 197 {
 198         struct tpacket_stats stats;
 199         socklen_t ssize;
 200         int ret[2];
 201
 202         ssize = sizeof(stats);
 203         if (getsockopt(fds[0], SOL_PACKET, PACKET_STATISTICS, &stats, &ssize)) {
 204                 perror("getsockopt statistics 0");
 205                 exit(1);
 206         }
 207         ret[0] = stats.tp_packets - stats.tp_drops;
 208         ssize = sizeof(stats);
 209         if (getsockopt(fds[1], SOL_PACKET, PACKET_STATISTICS, &stats, &ssize)) {
 210                 perror("getsockopt statistics 1");
 211                 exit(1);
 212         }
 213         ret[1] = stats.tp_packets - stats.tp_drops;
 214
 215         fprintf(stderr, "info: count=%d,%d, expect=%d,%d\n",
 216                         ret[0], ret[1], expect[0], expect[1]);
 217
 218         if ((!(ret[0] == expect[0] && ret[1] == expect[1])) &&
 219             (!(ret[0] == expect[1] && ret[1] == expect[0]))) {
 220                 fprintf(stderr, "ERROR: incorrect queue lengths\n");
 221                 exit(1);
 222         }
 223 }
 224
 225 /* Test illegal mode + flag combination */
 226 static void test_control_single(void)
 227 {
 228         fprintf(stderr, "test: control single socket\n");
 229
 230         if (sock_fanout_open(PACKET_FANOUT_ROLLOVER |
 231                                PACKET_FANOUT_FLAG_ROLLOVER, 0) != -1) {
 232                 fprintf(stderr, "ERROR: opened socket with dual rollover\n");
 233                 exit(1);
 234         }
 235 }
 236
 237 /* Test illegal group with different modes or flags */
 238 static void test_control_group(void)
 239 {
 240         int fds[2];
 241
 242         fprintf(stderr, "test: control multiple sockets\n");
 243
 244         fds[0] = sock_fanout_open(PACKET_FANOUT_HASH, 20);
 245         if (fds[0] == -1) {
 246                 fprintf(stderr, "ERROR: failed to open HASH socket\n");
 247                 exit(1);
 248         }
 249         if (sock_fanout_open(PACKET_FANOUT_HASH |
 250                                PACKET_FANOUT_FLAG_DEFRAG, 10) != -1) {
 251                 fprintf(stderr, "ERROR: joined group with wrong flag defrag\n");
 252                 exit(1);
 253         }
 254         if (sock_fanout_open(PACKET_FANOUT_HASH |
 255                                PACKET_FANOUT_FLAG_ROLLOVER, 10) != -1) {
 256                 fprintf(stderr, "ERROR: joined group with wrong flag ro\n");
 257                 exit(1);
 258         }
 259         if (sock_fanout_open(PACKET_FANOUT_CPU, 10) != -1) {
 260                 fprintf(stderr, "ERROR: joined group with wrong mode\n");
 261                 exit(1);
 262         }
 263         fds[1] = sock_fanout_open(PACKET_FANOUT_HASH, 20);
 264         if (fds[1] == -1) {
 265                 fprintf(stderr, "ERROR: failed to join group\n");
 266                 exit(1);
 267         }
 268         if (close(fds[1]) || close(fds[0])) {
 269                 fprintf(stderr, "ERROR: closing sockets\n");
 270                 exit(1);
 271         }
 272 }
 273
 274 static void test_datapath(uint16_t typeflags,
 275                           const int expect1[], const int expect2[])
 276 {
 277         const int expect0[] = { 0, 0 };
 278         int fds[2], fds_udp[2][2];
 279
 280         fprintf(stderr, "test: datapath 0x%hx\n", typeflags);
 281
 282         fds[0] = sock_fanout_open(typeflags, 20);
 283         fds[1] = sock_fanout_open(typeflags, 20);
 284         if (fds[0] == -1 || fds[1] == -1) {
 285                 fprintf(stderr, "ERROR: failed open\n");
 286                 exit(1);
 287         }
 288         pair_udp_open(fds_udp[0], 8000);
 289         pair_udp_open(fds_udp[1], 8002);
 290         sock_fanout_read(fds, expect0);
 291
 292         /* Send data, but not enough to overflow a queue */
 293         pair_udp_send(fds_udp[0], 15);
 294         pair_udp_send(fds_udp[1], 5);
 295         sock_fanout_read(fds, expect1);
 296
 297         /* Send more data, overflow the queue */
 298         pair_udp_send(fds_udp[0], 15);
 299         /* TODO: ensure consistent order between expect1 and expect2 */
 300         sock_fanout_read(fds, expect2);
 301
 302         if (close(fds_udp[1][1]) || close(fds_udp[1][0]) ||
 303             close(fds_udp[0][1]) || close(fds_udp[0][0]) ||
 304             close(fds[1]) || close(fds[0])) {
 305                 fprintf(stderr, "close datapath\n");
 306                 exit(1);
 307         }
 308 }
 309
 310 int main(int argc, char **argv)
 311 {
 312         const int expect_hash[2][2]     = { { 15, 5 }, { 5, 0 } };
 313         const int expect_hash_rb[2][2]  = { { 15, 5 }, { 5, 10 } };
 314         const int expect_rb[2][2]       = { { 20, 0 }, { 0, 15 } };
 315
 316         test_control_single();
 317         test_control_group();
 318
 319         test_datapath(PACKET_FANOUT_HASH, expect_hash[0], expect_hash[1]);
 320         test_datapath(PACKET_FANOUT_HASH | PACKET_FANOUT_FLAG_ROLLOVER,
 321                       expect_hash_rb[0], expect_hash_rb[1]);
 322         test_datapath(PACKET_FANOUT_ROLLOVER, expect_rb[0], expect_rb[1]);
 323
 324         printf("OK. All tests passed\n");
 325         return 0;
 326 }