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 #include <linux/err.h>
21 
22 #include "bpf_rlimit.h"
23 #include "bpf_util.h"
24 #include "cgroup_helpers.h"
25 
26 #include "test_tcpnotify.h"
27 #include "trace_helpers.h"
28 
29 #define SOCKET_BUFFER_SIZE (getpagesize() < 8192L ? getpagesize() : 8192L)
30 
31 pthread_t tid;
32 int rx_callbacks;
33 
34 static void dummyfn(void *ctx, int cpu, void *data, __u32 size)
35 {
36 	struct tcp_notifier *t = data;
37 
38 	if (t->type != 0xde || t->subtype != 0xad ||
39 	    t->source != 0xbe || t->hash != 0xef)
40 		return;
41 	rx_callbacks++;
42 }
43 
44 void tcp_notifier_poller(struct perf_buffer *pb)
45 {
46 	int err;
47 
48 	while (1) {
49 		err = perf_buffer__poll(pb, 100);
50 		if (err < 0 && err != -EINTR) {
51 			printf("failed perf_buffer__poll: %d\n", err);
52 			return;
53 		}
54 	}
55 }
56 
57 static void *poller_thread(void *arg)
58 {
59 	struct perf_buffer *pb = arg;
60 
61 	tcp_notifier_poller(pb);
62 	return arg;
63 }
64 
65 int verify_result(const struct tcpnotify_globals *result)
66 {
67 	return (result->ncalls > 0 && result->ncalls == rx_callbacks ? 0 : 1);
68 }
69 
70 int main(int argc, char **argv)
71 {
72 	const char *file = "test_tcpnotify_kern.o";
73 	struct bpf_map *perf_map, *global_map;
74 	struct perf_buffer_opts pb_opts = {};
75 	struct tcpnotify_globals g = {0};
76 	struct perf_buffer *pb = NULL;
77 	const char *cg_path = "/foo";
78 	int prog_fd, rv, cg_fd = -1;
79 	int error = EXIT_FAILURE;
80 	struct bpf_object *obj;
81 	char test_script[80];
82 	cpu_set_t cpuset;
83 	__u32 key = 0;
84 
85 	CPU_ZERO(&cpuset);
86 	CPU_SET(0, &cpuset);
87 	pthread_setaffinity_np(pthread_self(), sizeof(cpu_set_t), &cpuset);
88 
89 	if (setup_cgroup_environment())
90 		goto err;
91 
92 	cg_fd = create_and_get_cgroup(cg_path);
93 	if (cg_fd < 0)
94 		goto err;
95 
96 	if (join_cgroup(cg_path))
97 		goto err;
98 
99 	if (bpf_prog_load(file, BPF_PROG_TYPE_SOCK_OPS, &obj, &prog_fd)) {
100 		printf("FAILED: load_bpf_file failed for: %s\n", file);
101 		goto err;
102 	}
103 
104 	rv = bpf_prog_attach(prog_fd, cg_fd, BPF_CGROUP_SOCK_OPS, 0);
105 	if (rv) {
106 		printf("FAILED: bpf_prog_attach: %d (%s)\n",
107 		       error, strerror(errno));
108 		goto err;
109 	}
110 
111 	perf_map = bpf_object__find_map_by_name(obj, "perf_event_map");
112 	if (!perf_map) {
113 		printf("FAIL:map '%s' not found\n", "perf_event_map");
114 		goto err;
115 	}
116 
117 	global_map = bpf_object__find_map_by_name(obj, "global_map");
118 	if (!global_map) {
119 		printf("FAIL:map '%s' not found\n", "global_map");
120 		return -1;
121 	}
122 
123 	pb_opts.sample_cb = dummyfn;
124 	pb = perf_buffer__new(bpf_map__fd(perf_map), 8, &pb_opts);
125 	if (IS_ERR(pb))
126 		goto err;
127 
128 	pthread_create(&tid, NULL, poller_thread, pb);
129 
130 	sprintf(test_script,
131 		"iptables -A INPUT -p tcp --dport %d -j DROP",
132 		TESTPORT);
133 	system(test_script);
134 
135 	sprintf(test_script,
136 		"nc 127.0.0.1 %d < /etc/passwd > /dev/null 2>&1 ",
137 		TESTPORT);
138 	system(test_script);
139 
140 	sprintf(test_script,
141 		"iptables -D INPUT -p tcp --dport %d -j DROP",
142 		TESTPORT);
143 	system(test_script);
144 
145 	rv = bpf_map_lookup_elem(bpf_map__fd(global_map), &key, &g);
146 	if (rv != 0) {
147 		printf("FAILED: bpf_map_lookup_elem returns %d\n", rv);
148 		goto err;
149 	}
150 
151 	sleep(10);
152 
153 	if (verify_result(&g)) {
154 		printf("FAILED: Wrong stats Expected %d calls, got %d\n",
155 			g.ncalls, rx_callbacks);
156 		goto err;
157 	}
158 
159 	printf("PASSED!\n");
160 	error = 0;
161 err:
162 	bpf_prog_detach(cg_fd, BPF_CGROUP_SOCK_OPS);
163 	close(cg_fd);
164 	cleanup_cgroup_environment();
165 	if (!IS_ERR_OR_NULL(pb))
166 		perf_buffer__free(pb);
167 	return error;
168 }
169