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 */
sock_fanout_open(uint16_t typeflags,int num_packets)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
sock_fanout_set_ebpf(int fd)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
sock_fanout_open_ring(int fd)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
sock_fanout_read_ring(int fd,void * ring)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
sock_fanout_read(int fds[],char * rings[],const int expect[])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 */
test_control_single(void)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 */
test_control_group(void)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
test_datapath(uint16_t typeflags,int port_off,const int expect1[],const int expect2[])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
set_cpuaffinity(int cpuid)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
main(int argc,char ** argv)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 }
374