1 | // SPDX-License-Identifier: GPL-2.0 |
2 | /* Copyright (c) 2021 Google LLC. */ |
3 | |
4 | #include <linux/bpf.h> |
5 | #include <bpf/bpf_helpers.h> |
6 | |
7 | __u32 pid = 0; |
8 | |
9 | char num_out[64] = {}; |
10 | long num_ret = 0; |
11 | |
12 | char ip_out[64] = {}; |
13 | long ip_ret = 0; |
14 | |
15 | char sym_out[64] = {}; |
16 | long sym_ret = 0; |
17 | |
18 | char addr_out[64] = {}; |
19 | long addr_ret = 0; |
20 | |
21 | char str_out[64] = {}; |
22 | long str_ret = 0; |
23 | |
24 | char over_out[6] = {}; |
25 | long over_ret = 0; |
26 | |
27 | char pad_out[10] = {}; |
28 | long pad_ret = 0; |
29 | |
30 | char noarg_out[64] = {}; |
31 | long noarg_ret = 0; |
32 | |
33 | long nobuf_ret = 0; |
34 | |
35 | extern const void schedule __ksym; |
36 | |
37 | SEC("raw_tp/sys_enter" ) |
38 | int handler(const void *ctx) |
39 | { |
40 | /* Convenient values to pretty-print */ |
41 | const __u8 ex_ipv4[] = {127, 0, 0, 1}; |
42 | const __u8 ex_ipv6[] = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1}; |
43 | static const char str1[] = "str1" ; |
44 | static const char longstr[] = "longstr" ; |
45 | |
46 | if ((int)bpf_get_current_pid_tgid() != pid) |
47 | return 0; |
48 | |
49 | /* Integer types */ |
50 | num_ret = BPF_SNPRINTF(num_out, sizeof(num_out), |
51 | "%d %u %x %li %llu %lX" , |
52 | -8, 9, 150, -424242, 1337, 0xDABBAD00); |
53 | /* IP addresses */ |
54 | ip_ret = BPF_SNPRINTF(ip_out, sizeof(ip_out), "%pi4 %pI6" , |
55 | &ex_ipv4, &ex_ipv6); |
56 | /* Symbol lookup formatting */ |
57 | sym_ret = BPF_SNPRINTF(sym_out, sizeof(sym_out), "%ps %pS %pB" , |
58 | &schedule, &schedule, &schedule); |
59 | /* Kernel pointers */ |
60 | addr_ret = BPF_SNPRINTF(addr_out, sizeof(addr_out), "%pK %px %p" , |
61 | 0, 0xFFFF00000ADD4E55, 0xFFFF00000ADD4E55); |
62 | /* Strings and single-byte character embedding */ |
63 | str_ret = BPF_SNPRINTF(str_out, sizeof(str_out), "%s % 9c %+2c %-3c %04c %0c %+05s" , |
64 | str1, 'a', 'b', 'c', 'd', 'e', longstr); |
65 | /* Overflow */ |
66 | over_ret = BPF_SNPRINTF(over_out, sizeof(over_out), "%%overflow" ); |
67 | /* Padding of fixed width numbers */ |
68 | pad_ret = BPF_SNPRINTF(pad_out, sizeof(pad_out), "%5d %0900000X" , 4, 4); |
69 | /* No args */ |
70 | noarg_ret = BPF_SNPRINTF(noarg_out, sizeof(noarg_out), "simple case" ); |
71 | /* No buffer */ |
72 | nobuf_ret = BPF_SNPRINTF(NULL, 0, "only interested in length %d" , 60); |
73 | |
74 | return 0; |
75 | } |
76 | |
77 | char _license[] SEC("license" ) = "GPL" ; |
78 | |