Linux Audio

Check our new training course

Loading...
v6.13.7
  1// SPDX-License-Identifier: GPL-2.0
  2/* Copyright (c) 2023 Meta Platforms, Inc. and affiliates. */
  3
  4#include "vmlinux.h"
  5#include <bpf/bpf_helpers.h>
  6
  7char _license[] SEC("license") = "GPL";
  8
  9struct {
 10	__uint(type, BPF_MAP_TYPE_HASH);
 11	__uint(max_entries, 1);
 12	__type(key, int);
 13	__type(value, int);
 14} hash_map SEC(".maps");
 15
 16struct {
 17	__uint(type, BPF_MAP_TYPE_STACK);
 18	__uint(max_entries, 1);
 19	__type(value, int);
 20} stack_map SEC(".maps");
 21
 22struct {
 23	__uint(type, BPF_MAP_TYPE_ARRAY);
 24	__uint(max_entries, 1);
 25	__type(key, int);
 26	__type(value, int);
 27} array_map SEC(".maps");
 28
 29const volatile pid_t pid;
 30long err = 0;
 31
 32static u64 callback(u64 map, u64 key, u64 val, u64 ctx, u64 flags)
 33{
 34	return 0;
 35}
 36
 37SEC("tp/syscalls/sys_enter_getpid")
 38int map_update(void *ctx)
 39{
 40	const int key = 0;
 41	const int val = 1;
 42
 43	if (pid != (bpf_get_current_pid_tgid() >> 32))
 44		return 0;
 45
 46	err = bpf_map_update_elem(&hash_map, &key, &val, BPF_NOEXIST);
 47
 48	return 0;
 49}
 50
 51SEC("tp/syscalls/sys_enter_getppid")
 52int map_delete(void *ctx)
 53{
 54	const int key = 0;
 55
 56	if (pid != (bpf_get_current_pid_tgid() >> 32))
 57		return 0;
 58
 59	err = bpf_map_delete_elem(&hash_map, &key);
 60
 61	return 0;
 62}
 63
 64SEC("tp/syscalls/sys_enter_getuid")
 65int map_push(void *ctx)
 66{
 67	const int val = 1;
 68
 69	if (pid != (bpf_get_current_pid_tgid() >> 32))
 70		return 0;
 71
 72	err = bpf_map_push_elem(&stack_map, &val, 0);
 73
 74	return 0;
 75}
 76
 77SEC("tp/syscalls/sys_enter_geteuid")
 78int map_pop(void *ctx)
 79{
 80	int val;
 81
 82	if (pid != (bpf_get_current_pid_tgid() >> 32))
 83		return 0;
 84
 85	err = bpf_map_pop_elem(&stack_map, &val);
 86
 87	return 0;
 88}
 89
 90SEC("tp/syscalls/sys_enter_getgid")
 91int map_peek(void *ctx)
 92{
 93	int val;
 94
 95	if (pid != (bpf_get_current_pid_tgid() >> 32))
 96		return 0;
 97
 98	err = bpf_map_peek_elem(&stack_map, &val);
 99
100	return 0;
101}
102
103SEC("tp/syscalls/sys_enter_gettid")
104int map_for_each_pass(void *ctx)
105{
106	const int key = 0;
107	const int val = 1;
108	const u64 flags = 0;
109	int callback_ctx;
110
111	if (pid != (bpf_get_current_pid_tgid() >> 32))
112		return 0;
113
114	bpf_map_update_elem(&array_map, &key, &val, flags);
115
116	err = bpf_for_each_map_elem(&array_map, callback, &callback_ctx, flags);
117
118	return 0;
119}
120
121SEC("tp/syscalls/sys_enter_getpgid")
122int map_for_each_fail(void *ctx)
123{
124	const int key = 0;
125	const int val = 1;
126	const u64 flags = BPF_NOEXIST;
127	int callback_ctx;
128
129	if (pid != (bpf_get_current_pid_tgid() >> 32))
130		return 0;
131
132	bpf_map_update_elem(&array_map, &key, &val, flags);
133
134	/* calling for_each with non-zero flags will return error */
135	err = bpf_for_each_map_elem(&array_map, callback, &callback_ctx, flags);
136
137	return 0;
138}
v6.8
  1// SPDX-License-Identifier: GPL-2.0
  2/* Copyright (c) 2023 Meta Platforms, Inc. and affiliates. */
  3
  4#include "vmlinux.h"
  5#include <bpf/bpf_helpers.h>
  6
  7char _license[] SEC("license") = "GPL";
  8
  9struct {
 10	__uint(type, BPF_MAP_TYPE_HASH);
 11	__uint(max_entries, 1);
 12	__type(key, int);
 13	__type(value, int);
 14} hash_map SEC(".maps");
 15
 16struct {
 17	__uint(type, BPF_MAP_TYPE_STACK);
 18	__uint(max_entries, 1);
 19	__type(value, int);
 20} stack_map SEC(".maps");
 21
 22struct {
 23	__uint(type, BPF_MAP_TYPE_ARRAY);
 24	__uint(max_entries, 1);
 25	__type(key, int);
 26	__type(value, int);
 27} array_map SEC(".maps");
 28
 29const volatile pid_t pid;
 30long err = 0;
 31
 32static u64 callback(u64 map, u64 key, u64 val, u64 ctx, u64 flags)
 33{
 34	return 0;
 35}
 36
 37SEC("tp/syscalls/sys_enter_getpid")
 38int map_update(void *ctx)
 39{
 40	const int key = 0;
 41	const int val = 1;
 42
 43	if (pid != (bpf_get_current_pid_tgid() >> 32))
 44		return 0;
 45
 46	err = bpf_map_update_elem(&hash_map, &key, &val, BPF_NOEXIST);
 47
 48	return 0;
 49}
 50
 51SEC("tp/syscalls/sys_enter_getppid")
 52int map_delete(void *ctx)
 53{
 54	const int key = 0;
 55
 56	if (pid != (bpf_get_current_pid_tgid() >> 32))
 57		return 0;
 58
 59	err = bpf_map_delete_elem(&hash_map, &key);
 60
 61	return 0;
 62}
 63
 64SEC("tp/syscalls/sys_enter_getuid")
 65int map_push(void *ctx)
 66{
 67	const int val = 1;
 68
 69	if (pid != (bpf_get_current_pid_tgid() >> 32))
 70		return 0;
 71
 72	err = bpf_map_push_elem(&stack_map, &val, 0);
 73
 74	return 0;
 75}
 76
 77SEC("tp/syscalls/sys_enter_geteuid")
 78int map_pop(void *ctx)
 79{
 80	int val;
 81
 82	if (pid != (bpf_get_current_pid_tgid() >> 32))
 83		return 0;
 84
 85	err = bpf_map_pop_elem(&stack_map, &val);
 86
 87	return 0;
 88}
 89
 90SEC("tp/syscalls/sys_enter_getgid")
 91int map_peek(void *ctx)
 92{
 93	int val;
 94
 95	if (pid != (bpf_get_current_pid_tgid() >> 32))
 96		return 0;
 97
 98	err = bpf_map_peek_elem(&stack_map, &val);
 99
100	return 0;
101}
102
103SEC("tp/syscalls/sys_enter_gettid")
104int map_for_each_pass(void *ctx)
105{
106	const int key = 0;
107	const int val = 1;
108	const u64 flags = 0;
109	int callback_ctx;
110
111	if (pid != (bpf_get_current_pid_tgid() >> 32))
112		return 0;
113
114	bpf_map_update_elem(&array_map, &key, &val, flags);
115
116	err = bpf_for_each_map_elem(&array_map, callback, &callback_ctx, flags);
117
118	return 0;
119}
120
121SEC("tp/syscalls/sys_enter_getpgid")
122int map_for_each_fail(void *ctx)
123{
124	const int key = 0;
125	const int val = 1;
126	const u64 flags = BPF_NOEXIST;
127	int callback_ctx;
128
129	if (pid != (bpf_get_current_pid_tgid() >> 32))
130		return 0;
131
132	bpf_map_update_elem(&array_map, &key, &val, flags);
133
134	/* calling for_each with non-zero flags will return error */
135	err = bpf_for_each_map_elem(&array_map, callback, &callback_ctx, flags);
136
137	return 0;
138}