1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
|
/*
* Copyright (c) 2017 Facebook
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of version 2 of the GNU General Public
* License as published by the Free Software Foundation.
*/
#define KBUILD_MODNAME "foo"
#include <linux/ptrace.h>
#include <linux/version.h>
#include <uapi/linux/bpf.h>
#include <uapi/linux/in6.h>
#include <bpf/bpf_helpers.h>
#include "bpf_legacy.h"
#include <bpf/bpf_tracing.h>
#define MAX_NR_PORTS 65536
/* map #0 */
struct bpf_map_def_legacy SEC("maps") port_a = {
.type = BPF_MAP_TYPE_ARRAY,
.key_size = sizeof(u32),
.value_size = sizeof(int),
.max_entries = MAX_NR_PORTS,
};
/* map #1 */
struct bpf_map_def_legacy SEC("maps") port_h = {
.type = BPF_MAP_TYPE_HASH,
.key_size = sizeof(u32),
.value_size = sizeof(int),
.max_entries = 1,
};
/* map #2 */
struct bpf_map_def_legacy SEC("maps") reg_result_h = {
.type = BPF_MAP_TYPE_HASH,
.key_size = sizeof(u32),
.value_size = sizeof(int),
.max_entries = 1,
};
/* map #3 */
struct bpf_map_def_legacy SEC("maps") inline_result_h = {
.type = BPF_MAP_TYPE_HASH,
.key_size = sizeof(u32),
.value_size = sizeof(int),
.max_entries = 1,
};
/* map #4 */ /* Test case #0 */
struct bpf_map_def_legacy SEC("maps") a_of_port_a = {
.type = BPF_MAP_TYPE_ARRAY_OF_MAPS,
.key_size = sizeof(u32),
.inner_map_idx = 0, /* map_fd[0] is port_a */
.max_entries = MAX_NR_PORTS,
};
/* map #5 */ /* Test case #1 */
struct bpf_map_def_legacy SEC("maps") h_of_port_a = {
.type = BPF_MAP_TYPE_HASH_OF_MAPS,
.key_size = sizeof(u32),
.inner_map_idx = 0, /* map_fd[0] is port_a */
.max_entries = 1,
};
/* map #6 */ /* Test case #2 */
struct bpf_map_def_legacy SEC("maps") h_of_port_h = {
.type = BPF_MAP_TYPE_HASH_OF_MAPS,
.key_size = sizeof(u32),
.inner_map_idx = 1, /* map_fd[1] is port_h */
.max_entries = 1,
};
static __always_inline int do_reg_lookup(void *inner_map, u32 port)
{
int *result;
result = bpf_map_lookup_elem(inner_map, &port);
return result ? *result : -ENOENT;
}
static __always_inline int do_inline_array_lookup(void *inner_map, u32 port)
{
int *result;
if (inner_map != &port_a)
return -EINVAL;
result = bpf_map_lookup_elem(&port_a, &port);
return result ? *result : -ENOENT;
}
static __always_inline int do_inline_hash_lookup(void *inner_map, u32 port)
{
int *result;
if (inner_map != &port_h)
return -EINVAL;
result = bpf_map_lookup_elem(&port_h, &port);
return result ? *result : -ENOENT;
}
SEC("kprobe/sys_connect")
int trace_sys_connect(struct pt_regs *ctx)
{
struct sockaddr_in6 *in6;
u16 test_case, port, dst6[8];
int addrlen, ret, inline_ret, ret_key = 0;
u32 port_key;
void *outer_map, *inner_map;
bool inline_hash = false;
in6 = (struct sockaddr_in6 *)PT_REGS_PARM2(ctx);
addrlen = (int)PT_REGS_PARM3(ctx);
if (addrlen != sizeof(*in6))
return 0;
ret = bpf_probe_read_user(dst6, sizeof(dst6), &in6->sin6_addr);
if (ret) {
inline_ret = ret;
goto done;
}
if (dst6[0] != 0xdead || dst6[1] != 0xbeef)
return 0;
test_case = dst6[7];
ret = bpf_probe_read_user(&port, sizeof(port), &in6->sin6_port);
if (ret) {
inline_ret = ret;
goto done;
}
port_key = port;
ret = -ENOENT;
if (test_case == 0) {
outer_map = &a_of_port_a;
} else if (test_case == 1) {
outer_map = &h_of_port_a;
} else if (test_case == 2) {
outer_map = &h_of_port_h;
} else {
ret = __LINE__;
inline_ret = ret;
goto done;
}
inner_map = bpf_map_lookup_elem(outer_map, &port_key);
if (!inner_map) {
ret = __LINE__;
inline_ret = ret;
goto done;
}
ret = do_reg_lookup(inner_map, port_key);
if (test_case == 0 || test_case == 1)
inline_ret = do_inline_array_lookup(inner_map, port_key);
else
inline_ret = do_inline_hash_lookup(inner_map, port_key);
done:
bpf_map_update_elem(®_result_h, &ret_key, &ret, BPF_ANY);
bpf_map_update_elem(&inline_result_h, &ret_key, &inline_ret, BPF_ANY);
return 0;
}
char _license[] SEC("license") = "GPL";
u32 _version SEC("version") = LINUX_VERSION_CODE;
|
