1 // SPDX-License-Identifier: GPL-2.0
2 #include <assert.h>
3 #include <bpf/bpf.h>
4 #include <linux/filter.h>
5 #include <stdio.h>
6 #include <stdlib.h>
7 #include <sys/sysinfo.h>
8
9 #include "bpf_util.h"
10 #include "cgroup_helpers.h"
11 #include "testing_helpers.h"
12
13 char bpf_log_buf[BPF_LOG_BUF_SIZE];
14
15 #define TEST_CGROUP "/test-bpf-cgroup-storage-buf/"
16
main(int argc,char ** argv)17 int main(int argc, char **argv)
18 {
19 struct bpf_insn prog[] = {
20 BPF_LD_MAP_FD(BPF_REG_1, 0), /* percpu map fd */
21 BPF_MOV64_IMM(BPF_REG_2, 0), /* flags, not used */
22 BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0,
23 BPF_FUNC_get_local_storage),
24 BPF_LDX_MEM(BPF_DW, BPF_REG_3, BPF_REG_0, 0),
25 BPF_ALU64_IMM(BPF_ADD, BPF_REG_3, 0x1),
26 BPF_STX_MEM(BPF_DW, BPF_REG_0, BPF_REG_3, 0),
27
28 BPF_LD_MAP_FD(BPF_REG_1, 0), /* map fd */
29 BPF_MOV64_IMM(BPF_REG_2, 0), /* flags, not used */
30 BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0,
31 BPF_FUNC_get_local_storage),
32 BPF_MOV64_IMM(BPF_REG_1, 1),
33 BPF_ATOMIC_OP(BPF_DW, BPF_ADD, BPF_REG_0, BPF_REG_1, 0),
34 BPF_LDX_MEM(BPF_DW, BPF_REG_1, BPF_REG_0, 0),
35 BPF_ALU64_IMM(BPF_AND, BPF_REG_1, 0x1),
36 BPF_MOV64_REG(BPF_REG_0, BPF_REG_1),
37 BPF_EXIT_INSN(),
38 };
39 size_t insns_cnt = ARRAY_SIZE(prog);
40 int error = EXIT_FAILURE;
41 int map_fd, percpu_map_fd, prog_fd, cgroup_fd;
42 struct bpf_cgroup_storage_key key;
43 unsigned long long value;
44 unsigned long long *percpu_value;
45 int cpu, nproc;
46
47 nproc = bpf_num_possible_cpus();
48 percpu_value = malloc(sizeof(*percpu_value) * nproc);
49 if (!percpu_value) {
50 printf("Not enough memory for per-cpu area (%d cpus)\n", nproc);
51 goto err;
52 }
53
54 /* Use libbpf 1.0 API mode */
55 libbpf_set_strict_mode(LIBBPF_STRICT_ALL);
56
57 map_fd = bpf_map_create(BPF_MAP_TYPE_CGROUP_STORAGE, NULL, sizeof(key),
58 sizeof(value), 0, NULL);
59 if (map_fd < 0) {
60 printf("Failed to create map: %s\n", strerror(errno));
61 goto out;
62 }
63
64 percpu_map_fd = bpf_map_create(BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE, NULL,
65 sizeof(key), sizeof(value), 0, NULL);
66 if (percpu_map_fd < 0) {
67 printf("Failed to create map: %s\n", strerror(errno));
68 goto out;
69 }
70
71 prog[0].imm = percpu_map_fd;
72 prog[7].imm = map_fd;
73 prog_fd = bpf_test_load_program(BPF_PROG_TYPE_CGROUP_SKB,
74 prog, insns_cnt, "GPL", 0,
75 bpf_log_buf, BPF_LOG_BUF_SIZE);
76 if (prog_fd < 0) {
77 printf("Failed to load bpf program: %s\n", bpf_log_buf);
78 goto out;
79 }
80
81 cgroup_fd = cgroup_setup_and_join(TEST_CGROUP);
82
83 /* Attach the bpf program */
84 if (bpf_prog_attach(prog_fd, cgroup_fd, BPF_CGROUP_INET_EGRESS, 0)) {
85 printf("Failed to attach bpf program\n");
86 goto err;
87 }
88
89 if (bpf_map_get_next_key(map_fd, NULL, &key)) {
90 printf("Failed to get the first key in cgroup storage\n");
91 goto err;
92 }
93
94 if (bpf_map_lookup_elem(map_fd, &key, &value)) {
95 printf("Failed to lookup cgroup storage 0\n");
96 goto err;
97 }
98
99 for (cpu = 0; cpu < nproc; cpu++)
100 percpu_value[cpu] = 1000;
101
102 if (bpf_map_update_elem(percpu_map_fd, &key, percpu_value, 0)) {
103 printf("Failed to update the data in the cgroup storage\n");
104 goto err;
105 }
106
107 /* Every second packet should be dropped */
108 assert(system("ping localhost -c 1 -W 1 -q > /dev/null") == 0);
109 assert(system("ping localhost -c 1 -W 1 -q > /dev/null"));
110 assert(system("ping localhost -c 1 -W 1 -q > /dev/null") == 0);
111
112 /* Check the counter in the cgroup local storage */
113 if (bpf_map_lookup_elem(map_fd, &key, &value)) {
114 printf("Failed to lookup cgroup storage\n");
115 goto err;
116 }
117
118 if (value != 3) {
119 printf("Unexpected data in the cgroup storage: %llu\n", value);
120 goto err;
121 }
122
123 /* Bump the counter in the cgroup local storage */
124 value++;
125 if (bpf_map_update_elem(map_fd, &key, &value, 0)) {
126 printf("Failed to update the data in the cgroup storage\n");
127 goto err;
128 }
129
130 /* Every second packet should be dropped */
131 assert(system("ping localhost -c 1 -W 1 -q > /dev/null") == 0);
132 assert(system("ping localhost -c 1 -W 1 -q > /dev/null"));
133 assert(system("ping localhost -c 1 -W 1 -q > /dev/null") == 0);
134
135 /* Check the final value of the counter in the cgroup local storage */
136 if (bpf_map_lookup_elem(map_fd, &key, &value)) {
137 printf("Failed to lookup the cgroup storage\n");
138 goto err;
139 }
140
141 if (value != 7) {
142 printf("Unexpected data in the cgroup storage: %llu\n", value);
143 goto err;
144 }
145
146 /* Check the final value of the counter in the percpu local storage */
147
148 for (cpu = 0; cpu < nproc; cpu++)
149 percpu_value[cpu] = 0;
150
151 if (bpf_map_lookup_elem(percpu_map_fd, &key, percpu_value)) {
152 printf("Failed to lookup the per-cpu cgroup storage\n");
153 goto err;
154 }
155
156 value = 0;
157 for (cpu = 0; cpu < nproc; cpu++)
158 value += percpu_value[cpu];
159
160 if (value != nproc * 1000 + 6) {
161 printf("Unexpected data in the per-cpu cgroup storage\n");
162 goto err;
163 }
164
165 error = 0;
166 printf("test_cgroup_storage:PASS\n");
167
168 err:
169 cleanup_cgroup_environment();
170 free(percpu_value);
171
172 out:
173 return error;
174 }
175