1// SPDX-License-Identifier: GPL-2.0
2#include <test_progs.h>
3#include "cgroup_helpers.h"
4
5#include <linux/tcp.h>
6#include <linux/netlink.h>
7#include "sockopt_sk.skel.h"
8
9#ifndef SOL_TCP
10#define SOL_TCP IPPROTO_TCP
11#endif
12
13#define SOL_CUSTOM			0xdeadbeef
14
15static int getsetsockopt(void)
16{
17	int fd, err;
18	union {
19		char u8[4];
20		__u32 u32;
21		char cc[16]; /* TCP_CA_NAME_MAX */
22		struct tcp_zerocopy_receive zc;
23	} buf = {};
24	socklen_t optlen;
25	char *big_buf = NULL;
26
27	fd = socket(AF_INET, SOCK_STREAM, 0);
28	if (fd < 0) {
29		log_err("Failed to create socket");
30		return -1;
31	}
32
33	/* IP_TOS - BPF bypass */
34
35	optlen = getpagesize() * 2;
36	big_buf = calloc(1, optlen);
37	if (!big_buf) {
38		log_err("Couldn't allocate two pages");
39		goto err;
40	}
41
42	*(int *)big_buf = 0x08;
43	err = setsockopt(fd, SOL_IP, IP_TOS, big_buf, optlen);
44	if (err) {
45		log_err("Failed to call setsockopt(IP_TOS)");
46		goto err;
47	}
48
49	memset(big_buf, 0, optlen);
50	optlen = 1;
51	err = getsockopt(fd, SOL_IP, IP_TOS, big_buf, &optlen);
52	if (err) {
53		log_err("Failed to call getsockopt(IP_TOS)");
54		goto err;
55	}
56
57	if (*big_buf != 0x08) {
58		log_err("Unexpected getsockopt(IP_TOS) optval 0x%x != 0x08",
59			(int)*big_buf);
60		goto err;
61	}
62
63	/* IP_TTL - EPERM */
64
65	buf.u8[0] = 1;
66	err = setsockopt(fd, SOL_IP, IP_TTL, &buf, 1);
67	if (!err || errno != EPERM) {
68		log_err("Unexpected success from setsockopt(IP_TTL)");
69		goto err;
70	}
71
72	/* SOL_CUSTOM - handled by BPF */
73
74	buf.u8[0] = 0x01;
75	err = setsockopt(fd, SOL_CUSTOM, 0, &buf, 1);
76	if (err) {
77		log_err("Failed to call setsockopt");
78		goto err;
79	}
80
81	buf.u32 = 0x00;
82	optlen = 4;
83	err = getsockopt(fd, SOL_CUSTOM, 0, &buf, &optlen);
84	if (err) {
85		log_err("Failed to call getsockopt");
86		goto err;
87	}
88
89	if (optlen != 1) {
90		log_err("Unexpected optlen %d != 1", optlen);
91		goto err;
92	}
93	if (buf.u8[0] != 0x01) {
94		log_err("Unexpected buf[0] 0x%02x != 0x01", buf.u8[0]);
95		goto err;
96	}
97
98	/* IP_FREEBIND - BPF can't access optval past PAGE_SIZE */
99
100	optlen = getpagesize() * 2;
101	memset(big_buf, 0, optlen);
102
103	err = setsockopt(fd, SOL_IP, IP_FREEBIND, big_buf, optlen);
104	if (err != 0) {
105		log_err("Failed to call setsockopt, ret=%d", err);
106		goto err;
107	}
108
109	err = getsockopt(fd, SOL_IP, IP_FREEBIND, big_buf, &optlen);
110	if (err != 0) {
111		log_err("Failed to call getsockopt, ret=%d", err);
112		goto err;
113	}
114
115	if (optlen != 1 || *(__u8 *)big_buf != 0x55) {
116		log_err("Unexpected IP_FREEBIND getsockopt, optlen=%d, optval=0x%x",
117			optlen, *(__u8 *)big_buf);
118	}
119
120	/* SO_SNDBUF is overwritten */
121
122	buf.u32 = 0x01010101;
123	err = setsockopt(fd, SOL_SOCKET, SO_SNDBUF, &buf, 4);
124	if (err) {
125		log_err("Failed to call setsockopt(SO_SNDBUF)");
126		goto err;
127	}
128
129	buf.u32 = 0x00;
130	optlen = 4;
131	err = getsockopt(fd, SOL_SOCKET, SO_SNDBUF, &buf, &optlen);
132	if (err) {
133		log_err("Failed to call getsockopt(SO_SNDBUF)");
134		goto err;
135	}
136
137	if (buf.u32 != 0x55AA*2) {
138		log_err("Unexpected getsockopt(SO_SNDBUF) 0x%x != 0x55AA*2",
139			buf.u32);
140		goto err;
141	}
142
143	/* TCP_CONGESTION can extend the string */
144
145	strcpy(buf.cc, "nv");
146	err = setsockopt(fd, SOL_TCP, TCP_CONGESTION, &buf, strlen("nv"));
147	if (err) {
148		log_err("Failed to call setsockopt(TCP_CONGESTION)");
149		goto err;
150	}
151
152
153	optlen = sizeof(buf.cc);
154	err = getsockopt(fd, SOL_TCP, TCP_CONGESTION, &buf, &optlen);
155	if (err) {
156		log_err("Failed to call getsockopt(TCP_CONGESTION)");
157		goto err;
158	}
159
160	if (strcmp(buf.cc, "cubic") != 0) {
161		log_err("Unexpected getsockopt(TCP_CONGESTION) %s != %s",
162			buf.cc, "cubic");
163		goto err;
164	}
165
166	/* TCP_ZEROCOPY_RECEIVE triggers */
167	memset(&buf, 0, sizeof(buf));
168	optlen = sizeof(buf.zc);
169	err = getsockopt(fd, SOL_TCP, TCP_ZEROCOPY_RECEIVE, &buf, &optlen);
170	if (err) {
171		log_err("Unexpected getsockopt(TCP_ZEROCOPY_RECEIVE) err=%d errno=%d",
172			err, errno);
173		goto err;
174	}
175
176	memset(&buf, 0, sizeof(buf));
177	buf.zc.address = 12345; /* Not page aligned. Rejected by tcp_zerocopy_receive() */
178	optlen = sizeof(buf.zc);
179	errno = 0;
180	err = getsockopt(fd, SOL_TCP, TCP_ZEROCOPY_RECEIVE, &buf, &optlen);
181	if (errno != EINVAL) {
182		log_err("Unexpected getsockopt(TCP_ZEROCOPY_RECEIVE) err=%d errno=%d",
183			err, errno);
184		goto err;
185	}
186
187	/* optval=NULL case is handled correctly */
188
189	close(fd);
190	fd = socket(AF_NETLINK, SOCK_RAW, 0);
191	if (fd < 0) {
192		log_err("Failed to create AF_NETLINK socket");
193		return -1;
194	}
195
196	buf.u32 = 1;
197	optlen = sizeof(__u32);
198	err = setsockopt(fd, SOL_NETLINK, NETLINK_ADD_MEMBERSHIP, &buf, optlen);
199	if (err) {
200		log_err("Unexpected getsockopt(NETLINK_ADD_MEMBERSHIP) err=%d errno=%d",
201			err, errno);
202		goto err;
203	}
204
205	optlen = 0;
206	err = getsockopt(fd, SOL_NETLINK, NETLINK_LIST_MEMBERSHIPS, NULL, &optlen);
207	if (err) {
208		log_err("Unexpected getsockopt(NETLINK_LIST_MEMBERSHIPS) err=%d errno=%d",
209			err, errno);
210		goto err;
211	}
212	ASSERT_EQ(optlen, 8, "Unexpected NETLINK_LIST_MEMBERSHIPS value");
213
214	free(big_buf);
215	close(fd);
216	return 0;
217err:
218	free(big_buf);
219	close(fd);
220	return -1;
221}
222
223static void run_test(int cgroup_fd)
224{
225	struct sockopt_sk *skel;
226
227	skel = sockopt_sk__open_and_load();
228	if (!ASSERT_OK_PTR(skel, "skel_load"))
229		goto cleanup;
230
231	skel->bss->page_size = getpagesize();
232
233	skel->links._setsockopt =
234		bpf_program__attach_cgroup(skel->progs._setsockopt, cgroup_fd);
235	if (!ASSERT_OK_PTR(skel->links._setsockopt, "setsockopt_link"))
236		goto cleanup;
237
238	skel->links._getsockopt =
239		bpf_program__attach_cgroup(skel->progs._getsockopt, cgroup_fd);
240	if (!ASSERT_OK_PTR(skel->links._getsockopt, "getsockopt_link"))
241		goto cleanup;
242
243	ASSERT_OK(getsetsockopt(), "getsetsockopt");
244
245cleanup:
246	sockopt_sk__destroy(skel);
247}
248
249void test_sockopt_sk(void)
250{
251	int cgroup_fd;
252
253	cgroup_fd = test__join_cgroup("/sockopt_sk");
254	if (!ASSERT_GE(cgroup_fd, 0, "join_cgroup /sockopt_sk"))
255		return;
256
257	run_test(cgroup_fd);
258	close(cgroup_fd);
259}
260