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_util.h"
23 #include "cgroup_helpers.h"
24 
25 #include "test_tcpnotify.h"
26 #include "trace_helpers.h"
27 #include "testing_helpers.h"
28 
29 #define SOCKET_BUFFER_SIZE (getpagesize() < 8192L ? getpagesize() : 8192L)
30 
31 pthread_t tid;
32 int rx_callbacks;
33 
dummyfn(void * ctx,int cpu,void * data,__u32 size)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 
tcp_notifier_poller(struct perf_buffer * pb)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 
poller_thread(void * arg)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 
verify_result(const struct tcpnotify_globals * result)65 int verify_result(const struct tcpnotify_globals *result)
66 {
67 	return (result->ncalls > 0 && result->ncalls == rx_callbacks ? 0 : 1);
68 }
69 
main(int argc,char ** argv)70 int main(int argc, char **argv)
71 {
72 	const char *file = "test_tcpnotify_kern.bpf.o";
73 	struct bpf_map *perf_map, *global_map;
74 	struct tcpnotify_globals g = {0};
75 	struct perf_buffer *pb = NULL;
76 	const char *cg_path = "/foo";
77 	int prog_fd, rv, cg_fd = -1;
78 	int error = EXIT_FAILURE;
79 	struct bpf_object *obj;
80 	char test_script[80];
81 	cpu_set_t cpuset;
82 	__u32 key = 0;
83 
84 	libbpf_set_strict_mode(LIBBPF_STRICT_ALL);
85 
86 	CPU_ZERO(&cpuset);
87 	CPU_SET(0, &cpuset);
88 	pthread_setaffinity_np(pthread_self(), sizeof(cpu_set_t), &cpuset);
89 
90 	cg_fd = cgroup_setup_and_join(cg_path);
91 	if (cg_fd < 0)
92 		goto err;
93 
94 	if (bpf_prog_test_load(file, BPF_PROG_TYPE_SOCK_OPS, &obj, &prog_fd)) {
95 		printf("FAILED: load_bpf_file failed for: %s\n", file);
96 		goto err;
97 	}
98 
99 	rv = bpf_prog_attach(prog_fd, cg_fd, BPF_CGROUP_SOCK_OPS, 0);
100 	if (rv) {
101 		printf("FAILED: bpf_prog_attach: %d (%s)\n",
102 		       error, strerror(errno));
103 		goto err;
104 	}
105 
106 	perf_map = bpf_object__find_map_by_name(obj, "perf_event_map");
107 	if (!perf_map) {
108 		printf("FAIL:map '%s' not found\n", "perf_event_map");
109 		goto err;
110 	}
111 
112 	global_map = bpf_object__find_map_by_name(obj, "global_map");
113 	if (!global_map) {
114 		printf("FAIL:map '%s' not found\n", "global_map");
115 		return -1;
116 	}
117 
118 	pb = perf_buffer__new(bpf_map__fd(perf_map), 8, dummyfn, NULL, NULL, NULL);
119 	if (!pb)
120 		goto err;
121 
122 	pthread_create(&tid, NULL, poller_thread, pb);
123 
124 	sprintf(test_script,
125 		"iptables -A INPUT -p tcp --dport %d -j DROP",
126 		TESTPORT);
127 	if (system(test_script)) {
128 		printf("FAILED: execute command: %s, err %d\n", test_script, -errno);
129 		goto err;
130 	}
131 
132 	sprintf(test_script,
133 		"nc 127.0.0.1 %d < /etc/passwd > /dev/null 2>&1 ",
134 		TESTPORT);
135 	if (system(test_script))
136 		printf("execute command: %s, err %d\n", test_script, -errno);
137 
138 	sprintf(test_script,
139 		"iptables -D INPUT -p tcp --dport %d -j DROP",
140 		TESTPORT);
141 	if (system(test_script)) {
142 		printf("FAILED: execute command: %s, err %d\n", test_script, -errno);
143 		goto err;
144 	}
145 
146 	rv = bpf_map_lookup_elem(bpf_map__fd(global_map), &key, &g);
147 	if (rv != 0) {
148 		printf("FAILED: bpf_map_lookup_elem returns %d\n", rv);
149 		goto err;
150 	}
151 
152 	sleep(10);
153 
154 	if (verify_result(&g)) {
155 		printf("FAILED: Wrong stats Expected %d calls, got %d\n",
156 			g.ncalls, rx_callbacks);
157 		goto err;
158 	}
159 
160 	printf("PASSED!\n");
161 	error = 0;
162 err:
163 	bpf_prog_detach(cg_fd, BPF_CGROUP_SOCK_OPS);
164 	close(cg_fd);
165 	cleanup_cgroup_environment();
166 	perf_buffer__free(pb);
167 	return error;
168 }
169