600 lines · c
1// SPDX-License-Identifier: GPL-2.02 3#define _GNU_SOURCE4 5#include <stddef.h>6#include <arpa/inet.h>7#include <error.h>8#include <errno.h>9#include <net/if.h>10#include <linux/in.h>11#include <linux/netlink.h>12#include <linux/rtnetlink.h>13#include <netinet/if_ether.h>14#include <netinet/ip.h>15#include <netinet/ip6.h>16#include <netinet/udp.h>17#include <stdbool.h>18#include <stdlib.h>19#include <stdio.h>20#include <string.h>21#include <sys/ioctl.h>22#include <sys/socket.h>23#include <sys/stat.h>24#include <sys/time.h>25#include <sys/types.h>26#include <unistd.h>27 28#ifndef ETH_MAX_MTU29#define ETH_MAX_MTU 0xFFFFU30#endif31 32#ifndef UDP_SEGMENT33#define UDP_SEGMENT 10334#endif35 36#ifndef UDP_MAX_SEGMENTS37#define UDP_MAX_SEGMENTS (1 << 7UL)38#endif39 40#define CONST_MTU_TEST 150041 42#define CONST_HDRLEN_V4 (sizeof(struct iphdr) + sizeof(struct udphdr))43#define CONST_HDRLEN_V6 (sizeof(struct ip6_hdr) + sizeof(struct udphdr))44 45#define CONST_MSS_V4 (CONST_MTU_TEST - CONST_HDRLEN_V4)46#define CONST_MSS_V6 (CONST_MTU_TEST - CONST_HDRLEN_V6)47 48#define CONST_MAX_SEGS_V4 (ETH_MAX_MTU / CONST_MSS_V4)49#define CONST_MAX_SEGS_V6 (ETH_MAX_MTU / CONST_MSS_V6)50 51static bool cfg_do_ipv4;52static bool cfg_do_ipv6;53static bool cfg_do_connected;54static bool cfg_do_connectionless;55static bool cfg_do_msgmore;56static bool cfg_do_recv = true;57static bool cfg_do_setsockopt;58static int cfg_specific_test_id = -1;59 60static unsigned short cfg_port = 9000;61 62static char buf[ETH_MAX_MTU];63 64struct testcase {65 int tlen; /* send() buffer size, may exceed mss */66 bool tfail; /* send() call is expected to fail */67 int gso_len; /* mss after applying gso */68 int r_num_mss; /* recv(): number of calls of full mss */69 int r_len_last; /* recv(): size of last non-mss dgram, if any */70 bool v6_ext_hdr; /* send() dgrams with IPv6 extension headers */71};72 73const struct in6_addr addr6 = {74 { { 0xfd, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1 } }, /* fd00::1 */75};76 77const struct in_addr addr4 = {78 __constant_htonl(0x0a000001), /* 10.0.0.1 */79};80 81static const char ipv6_hopopts_pad1[8] = { 0 };82 83struct testcase testcases_v4[] = {84 {85 /* no GSO: send a single byte */86 .tlen = 1,87 .r_len_last = 1,88 },89 {90 /* no GSO: send a single MSS */91 .tlen = CONST_MSS_V4,92 .r_num_mss = 1,93 },94 {95 /* no GSO: send a single MSS + 1B: fail */96 .tlen = CONST_MSS_V4 + 1,97 .tfail = true,98 },99 {100 /* send a single MSS: will fall back to no GSO */101 .tlen = CONST_MSS_V4,102 .gso_len = CONST_MSS_V4,103 .r_num_mss = 1,104 },105 {106 /* send a single MSS + 1B */107 .tlen = CONST_MSS_V4 + 1,108 .gso_len = CONST_MSS_V4,109 .r_num_mss = 1,110 .r_len_last = 1,111 },112 {113 /* send exactly 2 MSS */114 .tlen = CONST_MSS_V4 * 2,115 .gso_len = CONST_MSS_V4,116 .r_num_mss = 2,117 },118 {119 /* send 2 MSS + 1B */120 .tlen = (CONST_MSS_V4 * 2) + 1,121 .gso_len = CONST_MSS_V4,122 .r_num_mss = 2,123 .r_len_last = 1,124 },125 {126 /* send MAX segs */127 .tlen = (ETH_MAX_MTU / CONST_MSS_V4) * CONST_MSS_V4,128 .gso_len = CONST_MSS_V4,129 .r_num_mss = (ETH_MAX_MTU / CONST_MSS_V4),130 },131 132 {133 /* send MAX bytes */134 .tlen = ETH_MAX_MTU - CONST_HDRLEN_V4,135 .gso_len = CONST_MSS_V4,136 .r_num_mss = CONST_MAX_SEGS_V4,137 .r_len_last = ETH_MAX_MTU - CONST_HDRLEN_V4 -138 (CONST_MAX_SEGS_V4 * CONST_MSS_V4),139 },140 {141 /* send MAX + 1: fail */142 .tlen = ETH_MAX_MTU - CONST_HDRLEN_V4 + 1,143 .gso_len = CONST_MSS_V4,144 .tfail = true,145 },146 {147 /* send a single 1B MSS: will fall back to no GSO */148 .tlen = 1,149 .gso_len = 1,150 .r_num_mss = 1,151 },152 {153 /* send 2 1B segments */154 .tlen = 2,155 .gso_len = 1,156 .r_num_mss = 2,157 },158 {159 /* send 2B + 2B + 1B segments */160 .tlen = 5,161 .gso_len = 2,162 .r_num_mss = 2,163 .r_len_last = 1,164 },165 {166 /* send max number of min sized segments */167 .tlen = UDP_MAX_SEGMENTS,168 .gso_len = 1,169 .r_num_mss = UDP_MAX_SEGMENTS,170 },171 {172 /* send max number + 1 of min sized segments: fail */173 .tlen = UDP_MAX_SEGMENTS + 1,174 .gso_len = 1,175 .tfail = true,176 },177 {178 /* EOL */179 }180};181 182#ifndef IP6_MAX_MTU183#define IP6_MAX_MTU (ETH_MAX_MTU + sizeof(struct ip6_hdr))184#endif185 186struct testcase testcases_v6[] = {187 {188 /* no GSO: send a single byte */189 .tlen = 1,190 .r_len_last = 1,191 },192 {193 /* no GSO: send a single MSS */194 .tlen = CONST_MSS_V6,195 .r_num_mss = 1,196 },197 {198 /* no GSO: send a single MSS + 1B: fail */199 .tlen = CONST_MSS_V6 + 1,200 .tfail = true,201 },202 {203 /* send a single MSS: will fall back to no GSO */204 .tlen = CONST_MSS_V6,205 .gso_len = CONST_MSS_V6,206 .r_num_mss = 1,207 },208 {209 /* send a single MSS + 1B */210 .tlen = CONST_MSS_V6 + 1,211 .gso_len = CONST_MSS_V6,212 .r_num_mss = 1,213 .r_len_last = 1,214 },215 {216 /* send exactly 2 MSS */217 .tlen = CONST_MSS_V6 * 2,218 .gso_len = CONST_MSS_V6,219 .r_num_mss = 2,220 },221 {222 /* send 2 MSS + 1B */223 .tlen = (CONST_MSS_V6 * 2) + 1,224 .gso_len = CONST_MSS_V6,225 .r_num_mss = 2,226 .r_len_last = 1,227 },228 {229 /* send MAX segs */230 .tlen = (IP6_MAX_MTU / CONST_MSS_V6) * CONST_MSS_V6,231 .gso_len = CONST_MSS_V6,232 .r_num_mss = (IP6_MAX_MTU / CONST_MSS_V6),233 },234 235 {236 /* send MAX bytes */237 .tlen = IP6_MAX_MTU - CONST_HDRLEN_V6,238 .gso_len = CONST_MSS_V6,239 .r_num_mss = CONST_MAX_SEGS_V6,240 .r_len_last = IP6_MAX_MTU - CONST_HDRLEN_V6 -241 (CONST_MAX_SEGS_V6 * CONST_MSS_V6),242 },243 {244 /* send MAX + 1: fail */245 .tlen = IP6_MAX_MTU - CONST_HDRLEN_V6 + 1,246 .gso_len = CONST_MSS_V6,247 .tfail = true,248 },249 {250 /* send a single 1B MSS: will fall back to no GSO */251 .tlen = 1,252 .gso_len = 1,253 .r_num_mss = 1,254 },255 {256 /* send 2 1B segments */257 .tlen = 2,258 .gso_len = 1,259 .r_num_mss = 2,260 },261 {262 /* send 2 1B segments with extension headers */263 .tlen = 2,264 .gso_len = 1,265 .r_num_mss = 2,266 .v6_ext_hdr = true,267 },268 {269 /* send 2B + 2B + 1B segments */270 .tlen = 5,271 .gso_len = 2,272 .r_num_mss = 2,273 .r_len_last = 1,274 },275 {276 /* send max number of min sized segments */277 .tlen = UDP_MAX_SEGMENTS,278 .gso_len = 1,279 .r_num_mss = UDP_MAX_SEGMENTS,280 },281 {282 /* send max number + 1 of min sized segments: fail */283 .tlen = UDP_MAX_SEGMENTS + 1,284 .gso_len = 1,285 .tfail = true,286 },287 {288 /* EOL */289 }290};291 292static void set_pmtu_discover(int fd, bool is_ipv4)293{294 int level, name, val;295 296 if (is_ipv4) {297 level = SOL_IP;298 name = IP_MTU_DISCOVER;299 val = IP_PMTUDISC_DO;300 } else {301 level = SOL_IPV6;302 name = IPV6_MTU_DISCOVER;303 val = IPV6_PMTUDISC_DO;304 }305 306 if (setsockopt(fd, level, name, &val, sizeof(val)))307 error(1, errno, "setsockopt path mtu");308}309 310static unsigned int get_path_mtu(int fd, bool is_ipv4)311{312 socklen_t vallen;313 unsigned int mtu;314 int ret;315 316 vallen = sizeof(mtu);317 if (is_ipv4)318 ret = getsockopt(fd, SOL_IP, IP_MTU, &mtu, &vallen);319 else320 ret = getsockopt(fd, SOL_IPV6, IPV6_MTU, &mtu, &vallen);321 322 if (ret)323 error(1, errno, "getsockopt mtu");324 325 326 fprintf(stderr, "path mtu (read): %u\n", mtu);327 return mtu;328}329 330static bool __send_one(int fd, struct msghdr *msg, int flags)331{332 int ret;333 334 ret = sendmsg(fd, msg, flags);335 if (ret == -1 &&336 (errno == EMSGSIZE || errno == ENOMEM || errno == EINVAL))337 return false;338 if (ret == -1)339 error(1, errno, "sendmsg");340 if (ret != msg->msg_iov->iov_len)341 error(1, 0, "sendto: %d != %llu", ret,342 (unsigned long long)msg->msg_iov->iov_len);343 if (msg->msg_flags)344 error(1, 0, "sendmsg: return flags 0x%x\n", msg->msg_flags);345 346 return true;347}348 349static bool send_one(int fd, int len, int gso_len,350 struct sockaddr *addr, socklen_t alen)351{352 char control[CMSG_SPACE(sizeof(uint16_t))] = {0};353 struct msghdr msg = {0};354 struct iovec iov = {0};355 struct cmsghdr *cm;356 357 iov.iov_base = buf;358 iov.iov_len = len;359 360 msg.msg_iov = &iov;361 msg.msg_iovlen = 1;362 363 msg.msg_name = addr;364 msg.msg_namelen = alen;365 366 if (gso_len && !cfg_do_setsockopt) {367 msg.msg_control = control;368 msg.msg_controllen = sizeof(control);369 370 cm = CMSG_FIRSTHDR(&msg);371 cm->cmsg_level = SOL_UDP;372 cm->cmsg_type = UDP_SEGMENT;373 cm->cmsg_len = CMSG_LEN(sizeof(uint16_t));374 *((uint16_t *) CMSG_DATA(cm)) = gso_len;375 }376 377 /* If MSG_MORE, send 1 byte followed by remainder */378 if (cfg_do_msgmore && len > 1) {379 iov.iov_len = 1;380 if (!__send_one(fd, &msg, MSG_MORE))381 error(1, 0, "send 1B failed");382 383 iov.iov_base++;384 iov.iov_len = len - 1;385 }386 387 return __send_one(fd, &msg, 0);388}389 390static int recv_one(int fd, int flags)391{392 int ret;393 394 ret = recv(fd, buf, sizeof(buf), flags);395 if (ret == -1 && errno == EAGAIN && (flags & MSG_DONTWAIT))396 return 0;397 if (ret == -1)398 error(1, errno, "recv");399 400 return ret;401}402 403static void run_one(struct testcase *test, int fdt, int fdr,404 struct sockaddr *addr, socklen_t alen)405{406 int i, ret, val, mss;407 bool sent;408 409 fprintf(stderr, "ipv%d tx:%d gso:%d %s%s\n",410 addr->sa_family == AF_INET ? 4 : 6,411 test->tlen, test->gso_len,412 test->v6_ext_hdr ? "ext-hdr " : "",413 test->tfail ? "(fail)" : "");414 415 if (test->v6_ext_hdr) {416 if (setsockopt(fdt, IPPROTO_IPV6, IPV6_HOPOPTS,417 ipv6_hopopts_pad1, sizeof(ipv6_hopopts_pad1)))418 error(1, errno, "setsockopt ipv6 hopopts");419 }420 421 val = test->gso_len;422 if (cfg_do_setsockopt) {423 if (setsockopt(fdt, SOL_UDP, UDP_SEGMENT, &val, sizeof(val)))424 error(1, errno, "setsockopt udp segment");425 }426 427 sent = send_one(fdt, test->tlen, test->gso_len, addr, alen);428 if (sent && test->tfail)429 error(1, 0, "send succeeded while expecting failure");430 if (!sent && !test->tfail)431 error(1, 0, "send failed while expecting success");432 433 if (test->v6_ext_hdr) {434 if (setsockopt(fdt, IPPROTO_IPV6, IPV6_HOPOPTS, NULL, 0))435 error(1, errno, "setsockopt ipv6 hopopts clear");436 }437 438 if (!sent)439 return;440 441 if (!cfg_do_recv)442 return;443 444 if (test->gso_len)445 mss = test->gso_len;446 else447 mss = addr->sa_family == AF_INET ? CONST_MSS_V4 : CONST_MSS_V6;448 449 450 /* Recv all full MSS datagrams */451 for (i = 0; i < test->r_num_mss; i++) {452 ret = recv_one(fdr, 0);453 if (ret != mss)454 error(1, 0, "recv.%d: %d != %d", i, ret, mss);455 }456 457 /* Recv the non-full last datagram, if tlen was not a multiple of mss */458 if (test->r_len_last) {459 ret = recv_one(fdr, 0);460 if (ret != test->r_len_last)461 error(1, 0, "recv.%d: %d != %d (last)",462 i, ret, test->r_len_last);463 }464 465 /* Verify received all data */466 ret = recv_one(fdr, MSG_DONTWAIT);467 if (ret)468 error(1, 0, "recv: unexpected datagram");469}470 471static void run_all(int fdt, int fdr, struct sockaddr *addr, socklen_t alen)472{473 struct testcase *tests, *test;474 475 tests = addr->sa_family == AF_INET ? testcases_v4 : testcases_v6;476 477 for (test = tests; test->tlen; test++) {478 /* if a specific test is given, then skip all others */479 if (cfg_specific_test_id == -1 ||480 cfg_specific_test_id == test - tests)481 run_one(test, fdt, fdr, addr, alen);482 }483}484 485static void run_test(struct sockaddr *addr, socklen_t alen)486{487 struct timeval tv = { .tv_usec = 100 * 1000 };488 int fdr, fdt, val;489 490 fdr = socket(addr->sa_family, SOCK_DGRAM, 0);491 if (fdr == -1)492 error(1, errno, "socket r");493 494 if (cfg_do_recv) {495 if (bind(fdr, addr, alen))496 error(1, errno, "bind");497 }498 499 /* Have tests fail quickly instead of hang */500 if (setsockopt(fdr, SOL_SOCKET, SO_RCVTIMEO, &tv, sizeof(tv)))501 error(1, errno, "setsockopt rcv timeout");502 503 fdt = socket(addr->sa_family, SOCK_DGRAM, 0);504 if (fdt == -1)505 error(1, errno, "socket t");506 507 /* Do not fragment these datagrams: only succeed if GSO works */508 set_pmtu_discover(fdt, addr->sa_family == AF_INET);509 510 if (cfg_do_connectionless)511 run_all(fdt, fdr, addr, alen);512 513 if (cfg_do_connected) {514 if (connect(fdt, addr, alen))515 error(1, errno, "connect");516 517 val = get_path_mtu(fdt, addr->sa_family == AF_INET);518 if (val != CONST_MTU_TEST)519 error(1, 0, "bad path mtu %u\n", val);520 521 run_all(fdt, fdr, addr, 0 /* use connected addr */);522 }523 524 if (close(fdt))525 error(1, errno, "close t");526 if (close(fdr))527 error(1, errno, "close r");528}529 530static void run_test_v4(void)531{532 struct sockaddr_in addr = {0};533 534 addr.sin_family = AF_INET;535 addr.sin_port = htons(cfg_port);536 addr.sin_addr = addr4;537 538 run_test((void *)&addr, sizeof(addr));539}540 541static void run_test_v6(void)542{543 struct sockaddr_in6 addr = {0};544 545 addr.sin6_family = AF_INET6;546 addr.sin6_port = htons(cfg_port);547 addr.sin6_addr = addr6;548 549 run_test((void *)&addr, sizeof(addr));550}551 552static void parse_opts(int argc, char **argv)553{554 int c;555 556 while ((c = getopt(argc, argv, "46cCmRst:")) != -1) {557 switch (c) {558 case '4':559 cfg_do_ipv4 = true;560 break;561 case '6':562 cfg_do_ipv6 = true;563 break;564 case 'c':565 cfg_do_connected = true;566 break;567 case 'C':568 cfg_do_connectionless = true;569 break;570 case 'm':571 cfg_do_msgmore = true;572 break;573 case 'R':574 cfg_do_recv = false;575 break;576 case 's':577 cfg_do_setsockopt = true;578 break;579 case 't':580 cfg_specific_test_id = strtoul(optarg, NULL, 0);581 break;582 default:583 error(1, 0, "%s: parse error", argv[0]);584 }585 }586}587 588int main(int argc, char **argv)589{590 parse_opts(argc, argv);591 592 if (cfg_do_ipv4)593 run_test_v4();594 if (cfg_do_ipv6)595 run_test_v6();596 597 fprintf(stderr, "OK\n");598 return 0;599}600