1// SPDX-License-Identifier: GPL-2.0
  2#include <test_progs.h>
  3#include "cgroup_helpers.h"
  4
  5#include "sockopt_multi.skel.h"
  6
  7static int run_getsockopt_test(struct sockopt_multi *obj, int cg_parent,
  8			       int cg_child, int sock_fd)
  9{
 10	struct bpf_link *link_parent = NULL;
 11	struct bpf_link *link_child = NULL;
 12	socklen_t optlen;
 13	__u8 buf;
 14	int err;
 15
 16	/* Set IP_TOS to the expected value (0x80). */
 17
 18	buf = 0x80;
 19	err = setsockopt(sock_fd, SOL_IP, IP_TOS, &buf, 1);
 20	if (err < 0) {
 21		log_err("Failed to call setsockopt(IP_TOS)");
 22		goto detach;
 23	}
 24
 25	buf = 0x00;
 26	optlen = 1;
 27	err = getsockopt(sock_fd, SOL_IP, IP_TOS, &buf, &optlen);
 28	if (err) {
 29		log_err("Failed to call getsockopt(IP_TOS)");
 30		goto detach;
 31	}
 32
 33	if (buf != 0x80) {
 34		log_err("Unexpected getsockopt 0x%x != 0x80 without BPF", buf);
 35		err = -1;
 36		goto detach;
 37	}
 38
 39	/* Attach child program and make sure it returns new value:
 40	 * - kernel:      -> 0x80
 41	 * - child:  0x80 -> 0x90
 42	 */
 43
 44	link_child = bpf_program__attach_cgroup(obj->progs._getsockopt_child,
 45						cg_child);
 46	if (!ASSERT_OK_PTR(link_child, "cg-attach-getsockopt_child"))
 47		goto detach;
 48
 49	buf = 0x00;
 50	optlen = 1;
 51	err = getsockopt(sock_fd, SOL_IP, IP_TOS, &buf, &optlen);
 52	if (err) {
 53		log_err("Failed to call getsockopt(IP_TOS)");
 54		goto detach;
 55	}
 56
 57	if (buf != 0x90) {
 58		log_err("Unexpected getsockopt 0x%x != 0x90", buf);
 59		err = -1;
 60		goto detach;
 61	}
 62
 63	/* Attach parent program and make sure it returns new value:
 64	 * - kernel:      -> 0x80
 65	 * - child:  0x80 -> 0x90
 66	 * - parent: 0x90 -> 0xA0
 67	 */
 68
 69	link_parent = bpf_program__attach_cgroup(obj->progs._getsockopt_parent,
 70						 cg_parent);
 71	if (!ASSERT_OK_PTR(link_parent, "cg-attach-getsockopt_parent"))
 72		goto detach;
 73
 74	buf = 0x00;
 75	optlen = 1;
 76	err = getsockopt(sock_fd, SOL_IP, IP_TOS, &buf, &optlen);
 77	if (err) {
 78		log_err("Failed to call getsockopt(IP_TOS)");
 79		goto detach;
 80	}
 81
 82	if (buf != 0xA0) {
 83		log_err("Unexpected getsockopt 0x%x != 0xA0", buf);
 84		err = -1;
 85		goto detach;
 86	}
 87
 88	/* Setting unexpected initial sockopt should return EPERM:
 89	 * - kernel: -> 0x40
 90	 * - child:  unexpected 0x40, EPERM
 91	 * - parent: unexpected 0x40, EPERM
 92	 */
 93
 94	buf = 0x40;
 95	err = setsockopt(sock_fd, SOL_IP, IP_TOS, &buf, 1);
 96	if (err < 0) {
 97		log_err("Failed to call setsockopt(IP_TOS)");
 98		goto detach;
 99	}
100
101	buf = 0x00;
102	optlen = 1;
103	err = getsockopt(sock_fd, SOL_IP, IP_TOS, &buf, &optlen);
104	if (!err) {
105		log_err("Unexpected success from getsockopt(IP_TOS)");
106		goto detach;
107	}
108
109	/* Detach child program and make sure we still get EPERM:
110	 * - kernel: -> 0x40
111	 * - parent: unexpected 0x40, EPERM
112	 */
113
114	bpf_link__destroy(link_child);
115	link_child = NULL;
116
117	buf = 0x00;
118	optlen = 1;
119	err = getsockopt(sock_fd, SOL_IP, IP_TOS, &buf, &optlen);
120	if (!err) {
121		log_err("Unexpected success from getsockopt(IP_TOS)");
122		goto detach;
123	}
124
125	/* Set initial value to the one the parent program expects:
126	 * - kernel:      -> 0x90
127	 * - parent: 0x90 -> 0xA0
128	 */
129
130	buf = 0x90;
131	err = setsockopt(sock_fd, SOL_IP, IP_TOS, &buf, 1);
132	if (err < 0) {
133		log_err("Failed to call setsockopt(IP_TOS)");
134		goto detach;
135	}
136
137	buf = 0x00;
138	optlen = 1;
139	err = getsockopt(sock_fd, SOL_IP, IP_TOS, &buf, &optlen);
140	if (err) {
141		log_err("Failed to call getsockopt(IP_TOS)");
142		goto detach;
143	}
144
145	if (buf != 0xA0) {
146		log_err("Unexpected getsockopt 0x%x != 0xA0", buf);
147		err = -1;
148		goto detach;
149	}
150
151detach:
152	bpf_link__destroy(link_child);
153	bpf_link__destroy(link_parent);
154
155	return err;
156}
157
158static int run_setsockopt_test(struct sockopt_multi *obj, int cg_parent,
159			       int cg_child, int sock_fd)
160{
161	struct bpf_link *link_parent = NULL;
162	struct bpf_link *link_child = NULL;
163	socklen_t optlen;
164	__u8 buf;
165	int err;
166
167	/* Set IP_TOS to the expected value (0x80). */
168
169	buf = 0x80;
170	err = setsockopt(sock_fd, SOL_IP, IP_TOS, &buf, 1);
171	if (err < 0) {
172		log_err("Failed to call setsockopt(IP_TOS)");
173		goto detach;
174	}
175
176	buf = 0x00;
177	optlen = 1;
178	err = getsockopt(sock_fd, SOL_IP, IP_TOS, &buf, &optlen);
179	if (err) {
180		log_err("Failed to call getsockopt(IP_TOS)");
181		goto detach;
182	}
183
184	if (buf != 0x80) {
185		log_err("Unexpected getsockopt 0x%x != 0x80 without BPF", buf);
186		err = -1;
187		goto detach;
188	}
189
190	/* Attach child program and make sure it adds 0x10. */
191
192	link_child = bpf_program__attach_cgroup(obj->progs._setsockopt,
193						cg_child);
194	if (!ASSERT_OK_PTR(link_child, "cg-attach-setsockopt_child"))
195		goto detach;
196
197	buf = 0x80;
198	err = setsockopt(sock_fd, SOL_IP, IP_TOS, &buf, 1);
199	if (err < 0) {
200		log_err("Failed to call setsockopt(IP_TOS)");
201		goto detach;
202	}
203
204	buf = 0x00;
205	optlen = 1;
206	err = getsockopt(sock_fd, SOL_IP, IP_TOS, &buf, &optlen);
207	if (err) {
208		log_err("Failed to call getsockopt(IP_TOS)");
209		goto detach;
210	}
211
212	if (buf != 0x80 + 0x10) {
213		log_err("Unexpected getsockopt 0x%x != 0x80 + 0x10", buf);
214		err = -1;
215		goto detach;
216	}
217
218	/* Attach parent program and make sure it adds another 0x10. */
219
220	link_parent = bpf_program__attach_cgroup(obj->progs._setsockopt,
221						 cg_parent);
222	if (!ASSERT_OK_PTR(link_parent, "cg-attach-setsockopt_parent"))
223		goto detach;
224
225	buf = 0x80;
226	err = setsockopt(sock_fd, SOL_IP, IP_TOS, &buf, 1);
227	if (err < 0) {
228		log_err("Failed to call setsockopt(IP_TOS)");
229		goto detach;
230	}
231
232	buf = 0x00;
233	optlen = 1;
234	err = getsockopt(sock_fd, SOL_IP, IP_TOS, &buf, &optlen);
235	if (err) {
236		log_err("Failed to call getsockopt(IP_TOS)");
237		goto detach;
238	}
239
240	if (buf != 0x80 + 2 * 0x10) {
241		log_err("Unexpected getsockopt 0x%x != 0x80 + 2 * 0x10", buf);
242		err = -1;
243		goto detach;
244	}
245
246detach:
247	bpf_link__destroy(link_child);
248	bpf_link__destroy(link_parent);
249
250	return err;
251}
252
253void test_sockopt_multi(void)
254{
255	int cg_parent = -1, cg_child = -1;
256	struct sockopt_multi *obj = NULL;
257	int sock_fd = -1;
258
259	cg_parent = test__join_cgroup("/parent");
260	if (!ASSERT_GE(cg_parent, 0, "join_cgroup /parent"))
261		goto out;
262
263	cg_child = test__join_cgroup("/parent/child");
264	if (!ASSERT_GE(cg_child, 0, "join_cgroup /parent/child"))
265		goto out;
266
267	obj = sockopt_multi__open_and_load();
268	if (!ASSERT_OK_PTR(obj, "skel-load"))
269		goto out;
270
271	obj->bss->page_size = sysconf(_SC_PAGESIZE);
272
273	sock_fd = socket(AF_INET, SOCK_STREAM, 0);
274	if (!ASSERT_GE(sock_fd, 0, "socket"))
275		goto out;
276
277	ASSERT_OK(run_getsockopt_test(obj, cg_parent, cg_child, sock_fd), "getsockopt_test");
278	ASSERT_OK(run_setsockopt_test(obj, cg_parent, cg_child, sock_fd), "setsockopt_test");
279
280out:
281	close(sock_fd);
282	sockopt_multi__destroy(obj);
283	close(cg_child);
284	close(cg_parent);
285}