xref: /linux/tools/testing/selftests/bpf/test_tcpnotify_user.c (revision 63307d015b91e626c97bb82e88054af3d0b74643)
1 // SPDX-License-Identifier: GPL-2.0
2 #define _GNU_SOURCE
3 #include <pthread.h>
4 #include <inttypes.h>
5 #include <stdio.h>
6 #include <stdlib.h>
7 #include <unistd.h>
8 #include <asm/types.h>
9 #include <sys/syscall.h>
10 #include <errno.h>
11 #include <string.h>
12 #include <linux/bpf.h>
13 #include <sys/socket.h>
14 #include <bpf/bpf.h>
15 #include <bpf/libbpf.h>
16 #include <sys/ioctl.h>
17 #include <linux/rtnetlink.h>
18 #include <signal.h>
19 #include <linux/perf_event.h>
20 
21 #include "bpf_rlimit.h"
22 #include "bpf_util.h"
23 #include "cgroup_helpers.h"
24 
25 #include "test_tcpnotify.h"
26 #include "trace_helpers.h"
27 
28 #define SOCKET_BUFFER_SIZE (getpagesize() < 8192L ? getpagesize() : 8192L)
29 
30 pthread_t tid;
31 int rx_callbacks;
32 
33 static int dummyfn(void *data, int size)
34 {
35 	struct tcp_notifier *t = data;
36 
37 	if (t->type != 0xde || t->subtype != 0xad ||
38 	    t->source != 0xbe || t->hash != 0xef)
39 		return 1;
40 	rx_callbacks++;
41 	return 0;
42 }
43 
44 void tcp_notifier_poller(int fd)
45 {
46 	while (1)
47 		perf_event_poller(fd, dummyfn);
48 }
49 
50 static void *poller_thread(void *arg)
51 {
52 	int fd = *(int *)arg;
53 
54 	tcp_notifier_poller(fd);
55 	return arg;
56 }
57 
58 int verify_result(const struct tcpnotify_globals *result)
59 {
60 	return (result->ncalls > 0 && result->ncalls == rx_callbacks ? 0 : 1);
61 }
62 
63 static int bpf_find_map(const char *test, struct bpf_object *obj,
64 			const char *name)
65 {
66 	struct bpf_map *map;
67 
68 	map = bpf_object__find_map_by_name(obj, name);
69 	if (!map) {
70 		printf("%s:FAIL:map '%s' not found\n", test, name);
71 		return -1;
72 	}
73 	return bpf_map__fd(map);
74 }
75 
76 static int setup_bpf_perf_event(int mapfd)
77 {
78 	struct perf_event_attr attr = {
79 		.sample_type = PERF_SAMPLE_RAW,
80 		.type = PERF_TYPE_SOFTWARE,
81 		.config = PERF_COUNT_SW_BPF_OUTPUT,
82 	};
83 	int key = 0;
84 	int pmu_fd;
85 
86 	pmu_fd = syscall(__NR_perf_event_open, &attr, -1, 0, -1, 0);
87 	if (pmu_fd < 0)
88 		return pmu_fd;
89 	bpf_map_update_elem(mapfd, &key, &pmu_fd, BPF_ANY);
90 
91 	ioctl(pmu_fd, PERF_EVENT_IOC_ENABLE, 0);
92 	return pmu_fd;
93 }
94 
95 int main(int argc, char **argv)
96 {
97 	const char *file = "test_tcpnotify_kern.o";
98 	int prog_fd, map_fd, perf_event_fd;
99 	struct tcpnotify_globals g = {0};
100 	const char *cg_path = "/foo";
101 	int error = EXIT_FAILURE;
102 	struct bpf_object *obj;
103 	int cg_fd = -1;
104 	__u32 key = 0;
105 	int rv;
106 	char test_script[80];
107 	int pmu_fd;
108 	cpu_set_t cpuset;
109 
110 	CPU_ZERO(&cpuset);
111 	CPU_SET(0, &cpuset);
112 	pthread_setaffinity_np(pthread_self(), sizeof(cpu_set_t), &cpuset);
113 
114 	if (setup_cgroup_environment())
115 		goto err;
116 
117 	cg_fd = create_and_get_cgroup(cg_path);
118 	if (cg_fd < 0)
119 		goto err;
120 
121 	if (join_cgroup(cg_path))
122 		goto err;
123 
124 	if (bpf_prog_load(file, BPF_PROG_TYPE_SOCK_OPS, &obj, &prog_fd)) {
125 		printf("FAILED: load_bpf_file failed for: %s\n", file);
126 		goto err;
127 	}
128 
129 	rv = bpf_prog_attach(prog_fd, cg_fd, BPF_CGROUP_SOCK_OPS, 0);
130 	if (rv) {
131 		printf("FAILED: bpf_prog_attach: %d (%s)\n",
132 		       error, strerror(errno));
133 		goto err;
134 	}
135 
136 	perf_event_fd = bpf_find_map(__func__, obj, "perf_event_map");
137 	if (perf_event_fd < 0)
138 		goto err;
139 
140 	map_fd = bpf_find_map(__func__, obj, "global_map");
141 	if (map_fd < 0)
142 		goto err;
143 
144 	pmu_fd = setup_bpf_perf_event(perf_event_fd);
145 	if (pmu_fd < 0 || perf_event_mmap(pmu_fd) < 0)
146 		goto err;
147 
148 	pthread_create(&tid, NULL, poller_thread, (void *)&pmu_fd);
149 
150 	sprintf(test_script,
151 		"iptables -A INPUT -p tcp --dport %d -j DROP",
152 		TESTPORT);
153 	system(test_script);
154 
155 	sprintf(test_script,
156 		"nc 127.0.0.1 %d < /etc/passwd > /dev/null 2>&1 ",
157 		TESTPORT);
158 	system(test_script);
159 
160 	sprintf(test_script,
161 		"iptables -D INPUT -p tcp --dport %d -j DROP",
162 		TESTPORT);
163 	system(test_script);
164 
165 	rv = bpf_map_lookup_elem(map_fd, &key, &g);
166 	if (rv != 0) {
167 		printf("FAILED: bpf_map_lookup_elem returns %d\n", rv);
168 		goto err;
169 	}
170 
171 	sleep(10);
172 
173 	if (verify_result(&g)) {
174 		printf("FAILED: Wrong stats Expected %d calls, got %d\n",
175 			g.ncalls, rx_callbacks);
176 		goto err;
177 	}
178 
179 	printf("PASSED!\n");
180 	error = 0;
181 err:
182 	bpf_prog_detach(cg_fd, BPF_CGROUP_SOCK_OPS);
183 	close(cg_fd);
184 	cleanup_cgroup_environment();
185 	return error;
186 }
187