1// SPDX-License-Identifier: GPL-2.0
2/*
3 * This testsuite provides conformance testing for GRO coalescing.
4 *
5 * Test cases:
6 * 1.data
7 *  Data packets of the same size and same header setup with correct
8 *  sequence numbers coalesce. The one exception being the last data
9 *  packet coalesced: it can be smaller than the rest and coalesced
10 *  as long as it is in the same flow.
11 * 2.ack
12 *  Pure ACK does not coalesce.
13 * 3.flags
14 *  Specific test cases: no packets with PSH, SYN, URG, RST set will
15 *  be coalesced.
16 * 4.tcp
17 *  Packets with incorrect checksum, non-consecutive seqno and
18 *  different TCP header options shouldn't coalesce. Nit: given that
19 *  some extension headers have paddings, such as timestamp, headers
20 *  that are padding differently would not be coalesced.
21 * 5.ip:
22 *  Packets with different (ECN, TTL, TOS) header, ip options or
23 *  ip fragments (ipv6) shouldn't coalesce.
24 * 6.large:
25 *  Packets larger than GRO_MAX_SIZE packets shouldn't coalesce.
26 *
27 * MSS is defined as 4096 - header because if it is too small
28 * (i.e. 1500 MTU - header), it will result in many packets,
29 * increasing the "large" test case's flakiness. This is because
30 * due to time sensitivity in the coalescing window, the receiver
31 * may not coalesce all of the packets.
32 *
33 * Note the timing issue applies to all of the test cases, so some
34 * flakiness is to be expected.
35 *
36 */
37
38#define _GNU_SOURCE
39
40#include <arpa/inet.h>
41#include <errno.h>
42#include <error.h>
43#include <getopt.h>
44#include <linux/filter.h>
45#include <linux/if_packet.h>
46#include <linux/ipv6.h>
47#include <net/ethernet.h>
48#include <net/if.h>
49#include <netinet/in.h>
50#include <netinet/ip.h>
51#include <netinet/ip6.h>
52#include <netinet/tcp.h>
53#include <stdbool.h>
54#include <stddef.h>
55#include <stdio.h>
56#include <stdarg.h>
57#include <string.h>
58#include <unistd.h>
59
60#include "../kselftest.h"
61
62#define DPORT 8000
63#define SPORT 1500
64#define PAYLOAD_LEN 100
65#define NUM_PACKETS 4
66#define START_SEQ 100
67#define START_ACK 100
68#define ETH_P_NONE 0
69#define TOTAL_HDR_LEN (ETH_HLEN + sizeof(struct ipv6hdr) + sizeof(struct tcphdr))
70#define MSS (4096 - sizeof(struct tcphdr) - sizeof(struct ipv6hdr))
71#define MAX_PAYLOAD (IP_MAXPACKET - sizeof(struct tcphdr) - sizeof(struct ipv6hdr))
72#define NUM_LARGE_PKT (MAX_PAYLOAD / MSS)
73#define MAX_HDR_LEN (ETH_HLEN + sizeof(struct ipv6hdr) + sizeof(struct tcphdr))
74
75static const char *addr6_src = "fdaa::2";
76static const char *addr6_dst = "fdaa::1";
77static const char *addr4_src = "192.168.1.200";
78static const char *addr4_dst = "192.168.1.100";
79static int proto = -1;
80static uint8_t src_mac[ETH_ALEN], dst_mac[ETH_ALEN];
81static char *testname = "data";
82static char *ifname = "eth0";
83static char *smac = "aa:00:00:00:00:02";
84static char *dmac = "aa:00:00:00:00:01";
85static bool verbose;
86static bool tx_socket = true;
87static int tcp_offset = -1;
88static int total_hdr_len = -1;
89static int ethhdr_proto = -1;
90
91static void vlog(const char *fmt, ...)
92{
93	va_list args;
94
95	if (verbose) {
96		va_start(args, fmt);
97		vfprintf(stderr, fmt, args);
98		va_end(args);
99	}
100}
101
102static void setup_sock_filter(int fd)
103{
104	const int dport_off = tcp_offset + offsetof(struct tcphdr, dest);
105	const int ethproto_off = offsetof(struct ethhdr, h_proto);
106	int optlen = 0;
107	int ipproto_off;
108	int next_off;
109
110	if (proto == PF_INET)
111		next_off = offsetof(struct iphdr, protocol);
112	else
113		next_off = offsetof(struct ipv6hdr, nexthdr);
114	ipproto_off = ETH_HLEN + next_off;
115
116	if (strcmp(testname, "ip") == 0) {
117		if (proto == PF_INET)
118			optlen = sizeof(struct ip_timestamp);
119		else
120			optlen = sizeof(struct ip6_frag);
121	}
122
123	struct sock_filter filter[] = {
124			BPF_STMT(BPF_LD  + BPF_H   + BPF_ABS, ethproto_off),
125			BPF_JUMP(BPF_JMP + BPF_JEQ + BPF_K, ntohs(ethhdr_proto), 0, 7),
126			BPF_STMT(BPF_LD  + BPF_B   + BPF_ABS, ipproto_off),
127			BPF_JUMP(BPF_JMP + BPF_JEQ + BPF_K, IPPROTO_TCP, 0, 5),
128			BPF_STMT(BPF_LD  + BPF_H   + BPF_ABS, dport_off),
129			BPF_JUMP(BPF_JMP + BPF_JEQ + BPF_K, DPORT, 2, 0),
130			BPF_STMT(BPF_LD  + BPF_H   + BPF_ABS, dport_off + optlen),
131			BPF_JUMP(BPF_JMP + BPF_JEQ + BPF_K, DPORT, 0, 1),
132			BPF_STMT(BPF_RET + BPF_K, 0xFFFFFFFF),
133			BPF_STMT(BPF_RET + BPF_K, 0),
134	};
135
136	struct sock_fprog bpf = {
137		.len = ARRAY_SIZE(filter),
138		.filter = filter,
139	};
140
141	if (setsockopt(fd, SOL_SOCKET, SO_ATTACH_FILTER, &bpf, sizeof(bpf)) < 0)
142		error(1, errno, "error setting filter");
143}
144
145static uint32_t checksum_nofold(void *data, size_t len, uint32_t sum)
146{
147	uint16_t *words = data;
148	int i;
149
150	for (i = 0; i < len / 2; i++)
151		sum += words[i];
152	if (len & 1)
153		sum += ((char *)data)[len - 1];
154	return sum;
155}
156
157static uint16_t checksum_fold(void *data, size_t len, uint32_t sum)
158{
159	sum = checksum_nofold(data, len, sum);
160	while (sum > 0xFFFF)
161		sum = (sum & 0xFFFF) + (sum >> 16);
162	return ~sum;
163}
164
165static uint16_t tcp_checksum(void *buf, int payload_len)
166{
167	struct pseudo_header6 {
168		struct in6_addr saddr;
169		struct in6_addr daddr;
170		uint16_t protocol;
171		uint16_t payload_len;
172	} ph6;
173	struct pseudo_header4 {
174		struct in_addr saddr;
175		struct in_addr daddr;
176		uint16_t protocol;
177		uint16_t payload_len;
178	} ph4;
179	uint32_t sum = 0;
180
181	if (proto == PF_INET6) {
182		if (inet_pton(AF_INET6, addr6_src, &ph6.saddr) != 1)
183			error(1, errno, "inet_pton6 source ip pseudo");
184		if (inet_pton(AF_INET6, addr6_dst, &ph6.daddr) != 1)
185			error(1, errno, "inet_pton6 dest ip pseudo");
186		ph6.protocol = htons(IPPROTO_TCP);
187		ph6.payload_len = htons(sizeof(struct tcphdr) + payload_len);
188
189		sum = checksum_nofold(&ph6, sizeof(ph6), 0);
190	} else if (proto == PF_INET) {
191		if (inet_pton(AF_INET, addr4_src, &ph4.saddr) != 1)
192			error(1, errno, "inet_pton source ip pseudo");
193		if (inet_pton(AF_INET, addr4_dst, &ph4.daddr) != 1)
194			error(1, errno, "inet_pton dest ip pseudo");
195		ph4.protocol = htons(IPPROTO_TCP);
196		ph4.payload_len = htons(sizeof(struct tcphdr) + payload_len);
197
198		sum = checksum_nofold(&ph4, sizeof(ph4), 0);
199	}
200
201	return checksum_fold(buf, sizeof(struct tcphdr) + payload_len, sum);
202}
203
204static void read_MAC(uint8_t *mac_addr, char *mac)
205{
206	if (sscanf(mac, "%hhx:%hhx:%hhx:%hhx:%hhx:%hhx",
207		   &mac_addr[0], &mac_addr[1], &mac_addr[2],
208		   &mac_addr[3], &mac_addr[4], &mac_addr[5]) != 6)
209		error(1, 0, "sscanf");
210}
211
212static void fill_datalinklayer(void *buf)
213{
214	struct ethhdr *eth = buf;
215
216	memcpy(eth->h_dest, dst_mac, ETH_ALEN);
217	memcpy(eth->h_source, src_mac, ETH_ALEN);
218	eth->h_proto = ethhdr_proto;
219}
220
221static void fill_networklayer(void *buf, int payload_len)
222{
223	struct ipv6hdr *ip6h = buf;
224	struct iphdr *iph = buf;
225
226	if (proto == PF_INET6) {
227		memset(ip6h, 0, sizeof(*ip6h));
228
229		ip6h->version = 6;
230		ip6h->payload_len = htons(sizeof(struct tcphdr) + payload_len);
231		ip6h->nexthdr = IPPROTO_TCP;
232		ip6h->hop_limit = 8;
233		if (inet_pton(AF_INET6, addr6_src, &ip6h->saddr) != 1)
234			error(1, errno, "inet_pton source ip6");
235		if (inet_pton(AF_INET6, addr6_dst, &ip6h->daddr) != 1)
236			error(1, errno, "inet_pton dest ip6");
237	} else if (proto == PF_INET) {
238		memset(iph, 0, sizeof(*iph));
239
240		iph->version = 4;
241		iph->ihl = 5;
242		iph->ttl = 8;
243		iph->protocol	= IPPROTO_TCP;
244		iph->tot_len = htons(sizeof(struct tcphdr) +
245				payload_len + sizeof(struct iphdr));
246		iph->frag_off = htons(0x4000); /* DF = 1, MF = 0 */
247		if (inet_pton(AF_INET, addr4_src, &iph->saddr) != 1)
248			error(1, errno, "inet_pton source ip");
249		if (inet_pton(AF_INET, addr4_dst, &iph->daddr) != 1)
250			error(1, errno, "inet_pton dest ip");
251		iph->check = checksum_fold(buf, sizeof(struct iphdr), 0);
252	}
253}
254
255static void fill_transportlayer(void *buf, int seq_offset, int ack_offset,
256				int payload_len, int fin)
257{
258	struct tcphdr *tcph = buf;
259
260	memset(tcph, 0, sizeof(*tcph));
261
262	tcph->source = htons(SPORT);
263	tcph->dest = htons(DPORT);
264	tcph->seq = ntohl(START_SEQ + seq_offset);
265	tcph->ack_seq = ntohl(START_ACK + ack_offset);
266	tcph->ack = 1;
267	tcph->fin = fin;
268	tcph->doff = 5;
269	tcph->window = htons(TCP_MAXWIN);
270	tcph->urg_ptr = 0;
271	tcph->check = tcp_checksum(tcph, payload_len);
272}
273
274static void write_packet(int fd, char *buf, int len, struct sockaddr_ll *daddr)
275{
276	int ret = -1;
277
278	ret = sendto(fd, buf, len, 0, (struct sockaddr *)daddr, sizeof(*daddr));
279	if (ret == -1)
280		error(1, errno, "sendto failure");
281	if (ret != len)
282		error(1, errno, "sendto wrong length");
283}
284
285static void create_packet(void *buf, int seq_offset, int ack_offset,
286			  int payload_len, int fin)
287{
288	memset(buf, 0, total_hdr_len);
289	memset(buf + total_hdr_len, 'a', payload_len);
290	fill_transportlayer(buf + tcp_offset, seq_offset, ack_offset,
291			    payload_len, fin);
292	fill_networklayer(buf + ETH_HLEN, payload_len);
293	fill_datalinklayer(buf);
294}
295
296/* send one extra flag, not first and not last pkt */
297static void send_flags(int fd, struct sockaddr_ll *daddr, int psh, int syn,
298		       int rst, int urg)
299{
300	static char flag_buf[MAX_HDR_LEN + PAYLOAD_LEN];
301	static char buf[MAX_HDR_LEN + PAYLOAD_LEN];
302	int payload_len, pkt_size, flag, i;
303	struct tcphdr *tcph;
304
305	payload_len = PAYLOAD_LEN * psh;
306	pkt_size = total_hdr_len + payload_len;
307	flag = NUM_PACKETS / 2;
308
309	create_packet(flag_buf, flag * payload_len, 0, payload_len, 0);
310
311	tcph = (struct tcphdr *)(flag_buf + tcp_offset);
312	tcph->psh = psh;
313	tcph->syn = syn;
314	tcph->rst = rst;
315	tcph->urg = urg;
316	tcph->check = 0;
317	tcph->check = tcp_checksum(tcph, payload_len);
318
319	for (i = 0; i < NUM_PACKETS + 1; i++) {
320		if (i == flag) {
321			write_packet(fd, flag_buf, pkt_size, daddr);
322			continue;
323		}
324		create_packet(buf, i * PAYLOAD_LEN, 0, PAYLOAD_LEN, 0);
325		write_packet(fd, buf, total_hdr_len + PAYLOAD_LEN, daddr);
326	}
327}
328
329/* Test for data of same length, smaller than previous
330 * and of different lengths
331 */
332static void send_data_pkts(int fd, struct sockaddr_ll *daddr,
333			   int payload_len1, int payload_len2)
334{
335	static char buf[ETH_HLEN + IP_MAXPACKET];
336
337	create_packet(buf, 0, 0, payload_len1, 0);
338	write_packet(fd, buf, total_hdr_len + payload_len1, daddr);
339	create_packet(buf, payload_len1, 0, payload_len2, 0);
340	write_packet(fd, buf, total_hdr_len + payload_len2, daddr);
341}
342
343/* If incoming segments make tracked segment length exceed
344 * legal IP datagram length, do not coalesce
345 */
346static void send_large(int fd, struct sockaddr_ll *daddr, int remainder)
347{
348	static char pkts[NUM_LARGE_PKT][TOTAL_HDR_LEN + MSS];
349	static char last[TOTAL_HDR_LEN + MSS];
350	static char new_seg[TOTAL_HDR_LEN + MSS];
351	int i;
352
353	for (i = 0; i < NUM_LARGE_PKT; i++)
354		create_packet(pkts[i], i * MSS, 0, MSS, 0);
355	create_packet(last, NUM_LARGE_PKT * MSS, 0, remainder, 0);
356	create_packet(new_seg, (NUM_LARGE_PKT + 1) * MSS, 0, remainder, 0);
357
358	for (i = 0; i < NUM_LARGE_PKT; i++)
359		write_packet(fd, pkts[i], total_hdr_len + MSS, daddr);
360	write_packet(fd, last, total_hdr_len + remainder, daddr);
361	write_packet(fd, new_seg, total_hdr_len + remainder, daddr);
362}
363
364/* Pure acks and dup acks don't coalesce */
365static void send_ack(int fd, struct sockaddr_ll *daddr)
366{
367	static char buf[MAX_HDR_LEN];
368
369	create_packet(buf, 0, 0, 0, 0);
370	write_packet(fd, buf, total_hdr_len, daddr);
371	write_packet(fd, buf, total_hdr_len, daddr);
372	create_packet(buf, 0, 1, 0, 0);
373	write_packet(fd, buf, total_hdr_len, daddr);
374}
375
376static void recompute_packet(char *buf, char *no_ext, int extlen)
377{
378	struct tcphdr *tcphdr = (struct tcphdr *)(buf + tcp_offset);
379	struct ipv6hdr *ip6h = (struct ipv6hdr *)(buf + ETH_HLEN);
380	struct iphdr *iph = (struct iphdr *)(buf + ETH_HLEN);
381
382	memmove(buf, no_ext, total_hdr_len);
383	memmove(buf + total_hdr_len + extlen,
384		no_ext + total_hdr_len, PAYLOAD_LEN);
385
386	tcphdr->doff = tcphdr->doff + (extlen / 4);
387	tcphdr->check = 0;
388	tcphdr->check = tcp_checksum(tcphdr, PAYLOAD_LEN + extlen);
389	if (proto == PF_INET) {
390		iph->tot_len = htons(ntohs(iph->tot_len) + extlen);
391		iph->check = 0;
392		iph->check = checksum_fold(iph, sizeof(struct iphdr), 0);
393	} else {
394		ip6h->payload_len = htons(ntohs(ip6h->payload_len) + extlen);
395	}
396}
397
398static void tcp_write_options(char *buf, int kind, int ts)
399{
400	struct tcp_option_ts {
401		uint8_t kind;
402		uint8_t len;
403		uint32_t tsval;
404		uint32_t tsecr;
405	} *opt_ts = (void *)buf;
406	struct tcp_option_window {
407		uint8_t kind;
408		uint8_t len;
409		uint8_t shift;
410	} *opt_window = (void *)buf;
411
412	switch (kind) {
413	case TCPOPT_NOP:
414		buf[0] = TCPOPT_NOP;
415		break;
416	case TCPOPT_WINDOW:
417		memset(opt_window, 0, sizeof(struct tcp_option_window));
418		opt_window->kind = TCPOPT_WINDOW;
419		opt_window->len = TCPOLEN_WINDOW;
420		opt_window->shift = 0;
421		break;
422	case TCPOPT_TIMESTAMP:
423		memset(opt_ts, 0, sizeof(struct tcp_option_ts));
424		opt_ts->kind = TCPOPT_TIMESTAMP;
425		opt_ts->len = TCPOLEN_TIMESTAMP;
426		opt_ts->tsval = ts;
427		opt_ts->tsecr = 0;
428		break;
429	default:
430		error(1, 0, "unimplemented TCP option");
431		break;
432	}
433}
434
435/* TCP with options is always a permutation of {TS, NOP, NOP}.
436 * Implement different orders to verify coalescing stops.
437 */
438static void add_standard_tcp_options(char *buf, char *no_ext, int ts, int order)
439{
440	switch (order) {
441	case 0:
442		tcp_write_options(buf + total_hdr_len, TCPOPT_NOP, 0);
443		tcp_write_options(buf + total_hdr_len + 1, TCPOPT_NOP, 0);
444		tcp_write_options(buf + total_hdr_len + 2 /* two NOP opts */,
445				  TCPOPT_TIMESTAMP, ts);
446		break;
447	case 1:
448		tcp_write_options(buf + total_hdr_len, TCPOPT_NOP, 0);
449		tcp_write_options(buf + total_hdr_len + 1,
450				  TCPOPT_TIMESTAMP, ts);
451		tcp_write_options(buf + total_hdr_len + 1 + TCPOLEN_TIMESTAMP,
452				  TCPOPT_NOP, 0);
453		break;
454	case 2:
455		tcp_write_options(buf + total_hdr_len, TCPOPT_TIMESTAMP, ts);
456		tcp_write_options(buf + total_hdr_len + TCPOLEN_TIMESTAMP + 1,
457				  TCPOPT_NOP, 0);
458		tcp_write_options(buf + total_hdr_len + TCPOLEN_TIMESTAMP + 2,
459				  TCPOPT_NOP, 0);
460		break;
461	default:
462		error(1, 0, "unknown order");
463		break;
464	}
465	recompute_packet(buf, no_ext, TCPOLEN_TSTAMP_APPA);
466}
467
468/* Packets with invalid checksum don't coalesce. */
469static void send_changed_checksum(int fd, struct sockaddr_ll *daddr)
470{
471	static char buf[MAX_HDR_LEN + PAYLOAD_LEN];
472	struct tcphdr *tcph = (struct tcphdr *)(buf + tcp_offset);
473	int pkt_size = total_hdr_len + PAYLOAD_LEN;
474
475	create_packet(buf, 0, 0, PAYLOAD_LEN, 0);
476	write_packet(fd, buf, pkt_size, daddr);
477
478	create_packet(buf, PAYLOAD_LEN, 0, PAYLOAD_LEN, 0);
479	tcph->check = tcph->check - 1;
480	write_packet(fd, buf, pkt_size, daddr);
481}
482
483 /* Packets with non-consecutive sequence number don't coalesce.*/
484static void send_changed_seq(int fd, struct sockaddr_ll *daddr)
485{
486	static char buf[MAX_HDR_LEN + PAYLOAD_LEN];
487	struct tcphdr *tcph = (struct tcphdr *)(buf + tcp_offset);
488	int pkt_size = total_hdr_len + PAYLOAD_LEN;
489
490	create_packet(buf, 0, 0, PAYLOAD_LEN, 0);
491	write_packet(fd, buf, pkt_size, daddr);
492
493	create_packet(buf, PAYLOAD_LEN, 0, PAYLOAD_LEN, 0);
494	tcph->seq = ntohl(htonl(tcph->seq) + 1);
495	tcph->check = 0;
496	tcph->check = tcp_checksum(tcph, PAYLOAD_LEN);
497	write_packet(fd, buf, pkt_size, daddr);
498}
499
500 /* Packet with different timestamp option or different timestamps
501  * don't coalesce.
502  */
503static void send_changed_ts(int fd, struct sockaddr_ll *daddr)
504{
505	static char buf[MAX_HDR_LEN + PAYLOAD_LEN];
506	static char extpkt[sizeof(buf) + TCPOLEN_TSTAMP_APPA];
507	int pkt_size = total_hdr_len + PAYLOAD_LEN + TCPOLEN_TSTAMP_APPA;
508
509	create_packet(buf, 0, 0, PAYLOAD_LEN, 0);
510	add_standard_tcp_options(extpkt, buf, 0, 0);
511	write_packet(fd, extpkt, pkt_size, daddr);
512
513	create_packet(buf, PAYLOAD_LEN, 0, PAYLOAD_LEN, 0);
514	add_standard_tcp_options(extpkt, buf, 0, 0);
515	write_packet(fd, extpkt, pkt_size, daddr);
516
517	create_packet(buf, PAYLOAD_LEN * 2, 0, PAYLOAD_LEN, 0);
518	add_standard_tcp_options(extpkt, buf, 100, 0);
519	write_packet(fd, extpkt, pkt_size, daddr);
520
521	create_packet(buf, PAYLOAD_LEN * 3, 0, PAYLOAD_LEN, 0);
522	add_standard_tcp_options(extpkt, buf, 100, 1);
523	write_packet(fd, extpkt, pkt_size, daddr);
524
525	create_packet(buf, PAYLOAD_LEN * 4, 0, PAYLOAD_LEN, 0);
526	add_standard_tcp_options(extpkt, buf, 100, 2);
527	write_packet(fd, extpkt, pkt_size, daddr);
528}
529
530/* Packet with different tcp options don't coalesce. */
531static void send_diff_opt(int fd, struct sockaddr_ll *daddr)
532{
533	static char buf[MAX_HDR_LEN + PAYLOAD_LEN];
534	static char extpkt1[sizeof(buf) + TCPOLEN_TSTAMP_APPA];
535	static char extpkt2[sizeof(buf) + TCPOLEN_MAXSEG];
536	int extpkt1_size = total_hdr_len + PAYLOAD_LEN + TCPOLEN_TSTAMP_APPA;
537	int extpkt2_size = total_hdr_len + PAYLOAD_LEN + TCPOLEN_MAXSEG;
538
539	create_packet(buf, 0, 0, PAYLOAD_LEN, 0);
540	add_standard_tcp_options(extpkt1, buf, 0, 0);
541	write_packet(fd, extpkt1, extpkt1_size, daddr);
542
543	create_packet(buf, PAYLOAD_LEN, 0, PAYLOAD_LEN, 0);
544	add_standard_tcp_options(extpkt1, buf, 0, 0);
545	write_packet(fd, extpkt1, extpkt1_size, daddr);
546
547	create_packet(buf, PAYLOAD_LEN * 2, 0, PAYLOAD_LEN, 0);
548	tcp_write_options(extpkt2 + MAX_HDR_LEN, TCPOPT_NOP, 0);
549	tcp_write_options(extpkt2 + MAX_HDR_LEN + 1, TCPOPT_WINDOW, 0);
550	recompute_packet(extpkt2, buf, TCPOLEN_WINDOW + 1);
551	write_packet(fd, extpkt2, extpkt2_size, daddr);
552}
553
554static void add_ipv4_ts_option(void *buf, void *optpkt)
555{
556	struct ip_timestamp *ts = (struct ip_timestamp *)(optpkt + tcp_offset);
557	int optlen = sizeof(struct ip_timestamp);
558	struct iphdr *iph;
559
560	if (optlen % 4)
561		error(1, 0, "ipv4 timestamp length is not a multiple of 4B");
562
563	ts->ipt_code = IPOPT_TS;
564	ts->ipt_len = optlen;
565	ts->ipt_ptr = 5;
566	ts->ipt_flg = IPOPT_TS_TSONLY;
567
568	memcpy(optpkt, buf, tcp_offset);
569	memcpy(optpkt + tcp_offset + optlen, buf + tcp_offset,
570	       sizeof(struct tcphdr) + PAYLOAD_LEN);
571
572	iph = (struct iphdr *)(optpkt + ETH_HLEN);
573	iph->ihl = 5 + (optlen / 4);
574	iph->tot_len = htons(ntohs(iph->tot_len) + optlen);
575	iph->check = 0;
576	iph->check = checksum_fold(iph, sizeof(struct iphdr) + optlen, 0);
577}
578
579/* IPv4 options shouldn't coalesce */
580static void send_ip_options(int fd, struct sockaddr_ll *daddr)
581{
582	static char buf[MAX_HDR_LEN + PAYLOAD_LEN];
583	static char optpkt[sizeof(buf) + sizeof(struct ip_timestamp)];
584	int optlen = sizeof(struct ip_timestamp);
585	int pkt_size = total_hdr_len + PAYLOAD_LEN + optlen;
586
587	create_packet(buf, 0, 0, PAYLOAD_LEN, 0);
588	write_packet(fd, buf, total_hdr_len + PAYLOAD_LEN, daddr);
589
590	create_packet(buf, PAYLOAD_LEN * 1, 0, PAYLOAD_LEN, 0);
591	add_ipv4_ts_option(buf, optpkt);
592	write_packet(fd, optpkt, pkt_size, daddr);
593
594	create_packet(buf, PAYLOAD_LEN * 2, 0, PAYLOAD_LEN, 0);
595	write_packet(fd, buf, total_hdr_len + PAYLOAD_LEN, daddr);
596}
597
598/*  IPv4 fragments shouldn't coalesce */
599static void send_fragment4(int fd, struct sockaddr_ll *daddr)
600{
601	static char buf[IP_MAXPACKET];
602	struct iphdr *iph = (struct iphdr *)(buf + ETH_HLEN);
603	int pkt_size = total_hdr_len + PAYLOAD_LEN;
604
605	create_packet(buf, 0, 0, PAYLOAD_LEN, 0);
606	write_packet(fd, buf, pkt_size, daddr);
607
608	/* Once fragmented, packet would retain the total_len.
609	 * Tcp header is prepared as if rest of data is in follow-up frags,
610	 * but follow up frags aren't actually sent.
611	 */
612	memset(buf + total_hdr_len, 'a', PAYLOAD_LEN * 2);
613	fill_transportlayer(buf + tcp_offset, PAYLOAD_LEN, 0, PAYLOAD_LEN * 2, 0);
614	fill_networklayer(buf + ETH_HLEN, PAYLOAD_LEN);
615	fill_datalinklayer(buf);
616
617	iph->frag_off = htons(0x6000); // DF = 1, MF = 1
618	iph->check = 0;
619	iph->check = checksum_fold(iph, sizeof(struct iphdr), 0);
620	write_packet(fd, buf, pkt_size, daddr);
621}
622
623/* IPv4 packets with different ttl don't coalesce.*/
624static void send_changed_ttl(int fd, struct sockaddr_ll *daddr)
625{
626	int pkt_size = total_hdr_len + PAYLOAD_LEN;
627	static char buf[MAX_HDR_LEN + PAYLOAD_LEN];
628	struct iphdr *iph = (struct iphdr *)(buf + ETH_HLEN);
629
630	create_packet(buf, 0, 0, PAYLOAD_LEN, 0);
631	write_packet(fd, buf, pkt_size, daddr);
632
633	create_packet(buf, PAYLOAD_LEN, 0, PAYLOAD_LEN, 0);
634	iph->ttl = 7;
635	iph->check = 0;
636	iph->check = checksum_fold(iph, sizeof(struct iphdr), 0);
637	write_packet(fd, buf, pkt_size, daddr);
638}
639
640/* Packets with different tos don't coalesce.*/
641static void send_changed_tos(int fd, struct sockaddr_ll *daddr)
642{
643	int pkt_size = total_hdr_len + PAYLOAD_LEN;
644	static char buf[MAX_HDR_LEN + PAYLOAD_LEN];
645	struct iphdr *iph = (struct iphdr *)(buf + ETH_HLEN);
646	struct ipv6hdr *ip6h = (struct ipv6hdr *)(buf + ETH_HLEN);
647
648	create_packet(buf, 0, 0, PAYLOAD_LEN, 0);
649	write_packet(fd, buf, pkt_size, daddr);
650
651	create_packet(buf, PAYLOAD_LEN, 0, PAYLOAD_LEN, 0);
652	if (proto == PF_INET) {
653		iph->tos = 1;
654		iph->check = 0;
655		iph->check = checksum_fold(iph, sizeof(struct iphdr), 0);
656	} else if (proto == PF_INET6) {
657		ip6h->priority = 0xf;
658	}
659	write_packet(fd, buf, pkt_size, daddr);
660}
661
662/* Packets with different ECN don't coalesce.*/
663static void send_changed_ECN(int fd, struct sockaddr_ll *daddr)
664{
665	int pkt_size = total_hdr_len + PAYLOAD_LEN;
666	static char buf[MAX_HDR_LEN + PAYLOAD_LEN];
667	struct iphdr *iph = (struct iphdr *)(buf + ETH_HLEN);
668
669	create_packet(buf, 0, 0, PAYLOAD_LEN, 0);
670	write_packet(fd, buf, pkt_size, daddr);
671
672	create_packet(buf, PAYLOAD_LEN, 0, PAYLOAD_LEN, 0);
673	if (proto == PF_INET) {
674		buf[ETH_HLEN + 1] ^= 0x2; // ECN set to 10
675		iph->check = 0;
676		iph->check = checksum_fold(iph, sizeof(struct iphdr), 0);
677	} else {
678		buf[ETH_HLEN + 1] ^= 0x20; // ECN set to 10
679	}
680	write_packet(fd, buf, pkt_size, daddr);
681}
682
683/* IPv6 fragments and packets with extensions don't coalesce.*/
684static void send_fragment6(int fd, struct sockaddr_ll *daddr)
685{
686	static char buf[MAX_HDR_LEN + PAYLOAD_LEN];
687	static char extpkt[MAX_HDR_LEN + PAYLOAD_LEN +
688			   sizeof(struct ip6_frag)];
689	struct ipv6hdr *ip6h = (struct ipv6hdr *)(buf + ETH_HLEN);
690	struct ip6_frag *frag = (void *)(extpkt + tcp_offset);
691	int extlen = sizeof(struct ip6_frag);
692	int bufpkt_len = total_hdr_len + PAYLOAD_LEN;
693	int extpkt_len = bufpkt_len + extlen;
694	int i;
695
696	for (i = 0; i < 2; i++) {
697		create_packet(buf, PAYLOAD_LEN * i, 0, PAYLOAD_LEN, 0);
698		write_packet(fd, buf, bufpkt_len, daddr);
699	}
700
701	create_packet(buf, PAYLOAD_LEN * 2, 0, PAYLOAD_LEN, 0);
702	memset(extpkt, 0, extpkt_len);
703
704	ip6h->nexthdr = IPPROTO_FRAGMENT;
705	ip6h->payload_len = htons(ntohs(ip6h->payload_len) + extlen);
706	frag->ip6f_nxt = IPPROTO_TCP;
707
708	memcpy(extpkt, buf, tcp_offset);
709	memcpy(extpkt + tcp_offset + extlen, buf + tcp_offset,
710	       sizeof(struct tcphdr) + PAYLOAD_LEN);
711	write_packet(fd, extpkt, extpkt_len, daddr);
712
713	create_packet(buf, PAYLOAD_LEN * 3, 0, PAYLOAD_LEN, 0);
714	write_packet(fd, buf, bufpkt_len, daddr);
715}
716
717static void bind_packetsocket(int fd)
718{
719	struct sockaddr_ll daddr = {};
720
721	daddr.sll_family = AF_PACKET;
722	daddr.sll_protocol = ethhdr_proto;
723	daddr.sll_ifindex = if_nametoindex(ifname);
724	if (daddr.sll_ifindex == 0)
725		error(1, errno, "if_nametoindex");
726
727	if (bind(fd, (void *)&daddr, sizeof(daddr)) < 0)
728		error(1, errno, "could not bind socket");
729}
730
731static void set_timeout(int fd)
732{
733	struct timeval timeout;
734
735	timeout.tv_sec = 3;
736	timeout.tv_usec = 0;
737	if (setsockopt(fd, SOL_SOCKET, SO_RCVTIMEO, (char *)&timeout,
738		       sizeof(timeout)) < 0)
739		error(1, errno, "cannot set timeout, setsockopt failed");
740}
741
742static void check_recv_pkts(int fd, int *correct_payload,
743			    int correct_num_pkts)
744{
745	static char buffer[IP_MAXPACKET + ETH_HLEN + 1];
746	struct iphdr *iph = (struct iphdr *)(buffer + ETH_HLEN);
747	struct ipv6hdr *ip6h = (struct ipv6hdr *)(buffer + ETH_HLEN);
748	struct tcphdr *tcph;
749	bool bad_packet = false;
750	int tcp_ext_len = 0;
751	int ip_ext_len = 0;
752	int pkt_size = -1;
753	int data_len = 0;
754	int num_pkt = 0;
755	int i;
756
757	vlog("Expected {");
758	for (i = 0; i < correct_num_pkts; i++)
759		vlog("%d ", correct_payload[i]);
760	vlog("}, Total %d packets\nReceived {", correct_num_pkts);
761
762	while (1) {
763		pkt_size = recv(fd, buffer, IP_MAXPACKET + ETH_HLEN + 1, 0);
764		if (pkt_size < 0)
765			error(1, errno, "could not receive");
766
767		if (iph->version == 4)
768			ip_ext_len = (iph->ihl - 5) * 4;
769		else if (ip6h->version == 6 && ip6h->nexthdr != IPPROTO_TCP)
770			ip_ext_len = sizeof(struct ip6_frag);
771
772		tcph = (struct tcphdr *)(buffer + tcp_offset + ip_ext_len);
773
774		if (tcph->fin)
775			break;
776
777		tcp_ext_len = (tcph->doff - 5) * 4;
778		data_len = pkt_size - total_hdr_len - tcp_ext_len - ip_ext_len;
779		/* Min ethernet frame payload is 46(ETH_ZLEN - ETH_HLEN) by RFC 802.3.
780		 * Ipv4/tcp packets without at least 6 bytes of data will be padded.
781		 * Packet sockets are protocol agnostic, and will not trim the padding.
782		 */
783		if (pkt_size == ETH_ZLEN && iph->version == 4) {
784			data_len = ntohs(iph->tot_len)
785				- sizeof(struct tcphdr) - sizeof(struct iphdr);
786		}
787		vlog("%d ", data_len);
788		if (data_len != correct_payload[num_pkt]) {
789			vlog("[!=%d]", correct_payload[num_pkt]);
790			bad_packet = true;
791		}
792		num_pkt++;
793	}
794	vlog("}, Total %d packets.\n", num_pkt);
795	if (num_pkt != correct_num_pkts)
796		error(1, 0, "incorrect number of packets");
797	if (bad_packet)
798		error(1, 0, "incorrect packet geometry");
799
800	printf("Test succeeded\n\n");
801}
802
803static void gro_sender(void)
804{
805	static char fin_pkt[MAX_HDR_LEN];
806	struct sockaddr_ll daddr = {};
807	int txfd = -1;
808
809	txfd = socket(PF_PACKET, SOCK_RAW, IPPROTO_RAW);
810	if (txfd < 0)
811		error(1, errno, "socket creation");
812
813	memset(&daddr, 0, sizeof(daddr));
814	daddr.sll_ifindex = if_nametoindex(ifname);
815	if (daddr.sll_ifindex == 0)
816		error(1, errno, "if_nametoindex");
817	daddr.sll_family = AF_PACKET;
818	memcpy(daddr.sll_addr, dst_mac, ETH_ALEN);
819	daddr.sll_halen = ETH_ALEN;
820	create_packet(fin_pkt, PAYLOAD_LEN * 2, 0, 0, 1);
821
822	if (strcmp(testname, "data") == 0) {
823		send_data_pkts(txfd, &daddr, PAYLOAD_LEN, PAYLOAD_LEN);
824		write_packet(txfd, fin_pkt, total_hdr_len, &daddr);
825
826		send_data_pkts(txfd, &daddr, PAYLOAD_LEN, PAYLOAD_LEN / 2);
827		write_packet(txfd, fin_pkt, total_hdr_len, &daddr);
828
829		send_data_pkts(txfd, &daddr, PAYLOAD_LEN / 2, PAYLOAD_LEN);
830		write_packet(txfd, fin_pkt, total_hdr_len, &daddr);
831	} else if (strcmp(testname, "ack") == 0) {
832		send_ack(txfd, &daddr);
833		write_packet(txfd, fin_pkt, total_hdr_len, &daddr);
834	} else if (strcmp(testname, "flags") == 0) {
835		send_flags(txfd, &daddr, 1, 0, 0, 0);
836		write_packet(txfd, fin_pkt, total_hdr_len, &daddr);
837
838		send_flags(txfd, &daddr, 0, 1, 0, 0);
839		write_packet(txfd, fin_pkt, total_hdr_len, &daddr);
840
841		send_flags(txfd, &daddr, 0, 0, 1, 0);
842		write_packet(txfd, fin_pkt, total_hdr_len, &daddr);
843
844		send_flags(txfd, &daddr, 0, 0, 0, 1);
845		write_packet(txfd, fin_pkt, total_hdr_len, &daddr);
846	} else if (strcmp(testname, "tcp") == 0) {
847		send_changed_checksum(txfd, &daddr);
848		write_packet(txfd, fin_pkt, total_hdr_len, &daddr);
849
850		send_changed_seq(txfd, &daddr);
851		write_packet(txfd, fin_pkt, total_hdr_len, &daddr);
852
853		send_changed_ts(txfd, &daddr);
854		write_packet(txfd, fin_pkt, total_hdr_len, &daddr);
855
856		send_diff_opt(txfd, &daddr);
857		write_packet(txfd, fin_pkt, total_hdr_len, &daddr);
858	} else if (strcmp(testname, "ip") == 0) {
859		send_changed_ECN(txfd, &daddr);
860		write_packet(txfd, fin_pkt, total_hdr_len, &daddr);
861
862		send_changed_tos(txfd, &daddr);
863		write_packet(txfd, fin_pkt, total_hdr_len, &daddr);
864		if (proto == PF_INET) {
865			/* Modified packets may be received out of order.
866			 * Sleep function added to enforce test boundaries
867			 * so that fin pkts are not received prior to other pkts.
868			 */
869			sleep(1);
870			send_changed_ttl(txfd, &daddr);
871			write_packet(txfd, fin_pkt, total_hdr_len, &daddr);
872
873			sleep(1);
874			send_ip_options(txfd, &daddr);
875			sleep(1);
876			write_packet(txfd, fin_pkt, total_hdr_len, &daddr);
877
878			sleep(1);
879			send_fragment4(txfd, &daddr);
880			sleep(1);
881			write_packet(txfd, fin_pkt, total_hdr_len, &daddr);
882		} else if (proto == PF_INET6) {
883			send_fragment6(txfd, &daddr);
884			write_packet(txfd, fin_pkt, total_hdr_len, &daddr);
885		}
886	} else if (strcmp(testname, "large") == 0) {
887		/* 20 is the difference between min iphdr size
888		 * and min ipv6hdr size. Like MAX_HDR_SIZE,
889		 * MAX_PAYLOAD is defined with the larger header of the two.
890		 */
891		int offset = proto == PF_INET ? 20 : 0;
892		int remainder = (MAX_PAYLOAD + offset) % MSS;
893
894		send_large(txfd, &daddr, remainder);
895		write_packet(txfd, fin_pkt, total_hdr_len, &daddr);
896
897		send_large(txfd, &daddr, remainder + 1);
898		write_packet(txfd, fin_pkt, total_hdr_len, &daddr);
899	} else {
900		error(1, 0, "Unknown testcase");
901	}
902
903	if (close(txfd))
904		error(1, errno, "socket close");
905}
906
907static void gro_receiver(void)
908{
909	static int correct_payload[NUM_PACKETS];
910	int rxfd = -1;
911
912	rxfd = socket(PF_PACKET, SOCK_RAW, htons(ETH_P_NONE));
913	if (rxfd < 0)
914		error(1, 0, "socket creation");
915	setup_sock_filter(rxfd);
916	set_timeout(rxfd);
917	bind_packetsocket(rxfd);
918
919	memset(correct_payload, 0, sizeof(correct_payload));
920
921	if (strcmp(testname, "data") == 0) {
922		printf("pure data packet of same size: ");
923		correct_payload[0] = PAYLOAD_LEN * 2;
924		check_recv_pkts(rxfd, correct_payload, 1);
925
926		printf("large data packets followed by a smaller one: ");
927		correct_payload[0] = PAYLOAD_LEN * 1.5;
928		check_recv_pkts(rxfd, correct_payload, 1);
929
930		printf("small data packets followed by a larger one: ");
931		correct_payload[0] = PAYLOAD_LEN / 2;
932		correct_payload[1] = PAYLOAD_LEN;
933		check_recv_pkts(rxfd, correct_payload, 2);
934	} else if (strcmp(testname, "ack") == 0) {
935		printf("duplicate ack and pure ack: ");
936		check_recv_pkts(rxfd, correct_payload, 3);
937	} else if (strcmp(testname, "flags") == 0) {
938		correct_payload[0] = PAYLOAD_LEN * 3;
939		correct_payload[1] = PAYLOAD_LEN * 2;
940
941		printf("psh flag ends coalescing: ");
942		check_recv_pkts(rxfd, correct_payload, 2);
943
944		correct_payload[0] = PAYLOAD_LEN * 2;
945		correct_payload[1] = 0;
946		correct_payload[2] = PAYLOAD_LEN * 2;
947		printf("syn flag ends coalescing: ");
948		check_recv_pkts(rxfd, correct_payload, 3);
949
950		printf("rst flag ends coalescing: ");
951		check_recv_pkts(rxfd, correct_payload, 3);
952
953		printf("urg flag ends coalescing: ");
954		check_recv_pkts(rxfd, correct_payload, 3);
955	} else if (strcmp(testname, "tcp") == 0) {
956		correct_payload[0] = PAYLOAD_LEN;
957		correct_payload[1] = PAYLOAD_LEN;
958		correct_payload[2] = PAYLOAD_LEN;
959		correct_payload[3] = PAYLOAD_LEN;
960
961		printf("changed checksum does not coalesce: ");
962		check_recv_pkts(rxfd, correct_payload, 2);
963
964		printf("Wrong Seq number doesn't coalesce: ");
965		check_recv_pkts(rxfd, correct_payload, 2);
966
967		printf("Different timestamp doesn't coalesce: ");
968		correct_payload[0] = PAYLOAD_LEN * 2;
969		check_recv_pkts(rxfd, correct_payload, 4);
970
971		printf("Different options doesn't coalesce: ");
972		correct_payload[0] = PAYLOAD_LEN * 2;
973		check_recv_pkts(rxfd, correct_payload, 2);
974	} else if (strcmp(testname, "ip") == 0) {
975		correct_payload[0] = PAYLOAD_LEN;
976		correct_payload[1] = PAYLOAD_LEN;
977
978		printf("different ECN doesn't coalesce: ");
979		check_recv_pkts(rxfd, correct_payload, 2);
980
981		printf("different tos doesn't coalesce: ");
982		check_recv_pkts(rxfd, correct_payload, 2);
983
984		if (proto == PF_INET) {
985			printf("different ttl doesn't coalesce: ");
986			check_recv_pkts(rxfd, correct_payload, 2);
987
988			printf("ip options doesn't coalesce: ");
989			correct_payload[2] = PAYLOAD_LEN;
990			check_recv_pkts(rxfd, correct_payload, 3);
991
992			printf("fragmented ip4 doesn't coalesce: ");
993			check_recv_pkts(rxfd, correct_payload, 2);
994		} else if (proto == PF_INET6) {
995			/* GRO doesn't check for ipv6 hop limit when flushing.
996			 * Hence no corresponding test to the ipv4 case.
997			 */
998			printf("fragmented ip6 doesn't coalesce: ");
999			correct_payload[0] = PAYLOAD_LEN * 2;
1000			check_recv_pkts(rxfd, correct_payload, 2);
1001		}
1002	} else if (strcmp(testname, "large") == 0) {
1003		int offset = proto == PF_INET ? 20 : 0;
1004		int remainder = (MAX_PAYLOAD + offset) % MSS;
1005
1006		correct_payload[0] = (MAX_PAYLOAD + offset);
1007		correct_payload[1] = remainder;
1008		printf("Shouldn't coalesce if exceed IP max pkt size: ");
1009		check_recv_pkts(rxfd, correct_payload, 2);
1010
1011		/* last segment sent individually, doesn't start new segment */
1012		correct_payload[0] = correct_payload[0] - remainder;
1013		correct_payload[1] = remainder + 1;
1014		correct_payload[2] = remainder + 1;
1015		check_recv_pkts(rxfd, correct_payload, 3);
1016	} else {
1017		error(1, 0, "Test case error, should never trigger");
1018	}
1019
1020	if (close(rxfd))
1021		error(1, 0, "socket close");
1022}
1023
1024static void parse_args(int argc, char **argv)
1025{
1026	static const struct option opts[] = {
1027		{ "daddr", required_argument, NULL, 'd' },
1028		{ "dmac", required_argument, NULL, 'D' },
1029		{ "iface", required_argument, NULL, 'i' },
1030		{ "ipv4", no_argument, NULL, '4' },
1031		{ "ipv6", no_argument, NULL, '6' },
1032		{ "rx", no_argument, NULL, 'r' },
1033		{ "saddr", required_argument, NULL, 's' },
1034		{ "smac", required_argument, NULL, 'S' },
1035		{ "test", required_argument, NULL, 't' },
1036		{ "verbose", no_argument, NULL, 'v' },
1037		{ 0, 0, 0, 0 }
1038	};
1039	int c;
1040
1041	while ((c = getopt_long(argc, argv, "46d:D:i:rs:S:t:v", opts, NULL)) != -1) {
1042		switch (c) {
1043		case '4':
1044			proto = PF_INET;
1045			ethhdr_proto = htons(ETH_P_IP);
1046			break;
1047		case '6':
1048			proto = PF_INET6;
1049			ethhdr_proto = htons(ETH_P_IPV6);
1050			break;
1051		case 'd':
1052			addr4_dst = addr6_dst = optarg;
1053			break;
1054		case 'D':
1055			dmac = optarg;
1056			break;
1057		case 'i':
1058			ifname = optarg;
1059			break;
1060		case 'r':
1061			tx_socket = false;
1062			break;
1063		case 's':
1064			addr4_src = addr6_src = optarg;
1065			break;
1066		case 'S':
1067			smac = optarg;
1068			break;
1069		case 't':
1070			testname = optarg;
1071			break;
1072		case 'v':
1073			verbose = true;
1074			break;
1075		default:
1076			error(1, 0, "%s invalid option %c\n", __func__, c);
1077			break;
1078		}
1079	}
1080}
1081
1082int main(int argc, char **argv)
1083{
1084	parse_args(argc, argv);
1085
1086	if (proto == PF_INET) {
1087		tcp_offset = ETH_HLEN + sizeof(struct iphdr);
1088		total_hdr_len = tcp_offset + sizeof(struct tcphdr);
1089	} else if (proto == PF_INET6) {
1090		tcp_offset = ETH_HLEN + sizeof(struct ipv6hdr);
1091		total_hdr_len = MAX_HDR_LEN;
1092	} else {
1093		error(1, 0, "Protocol family is not ipv4 or ipv6");
1094	}
1095
1096	read_MAC(src_mac, smac);
1097	read_MAC(dst_mac, dmac);
1098
1099	if (tx_socket)
1100		gro_sender();
1101	else
1102		gro_receiver();
1103
1104	fprintf(stderr, "Gro::%s test passed.\n", testname);
1105	return 0;
1106}
1107