1 // SPDX-License-Identifier: GPL-2.0-only 2 /* Copyright (c) 2017 Facebook 3 */ 4 #include <uapi/linux/bpf.h> 5 #include "bpf_helpers.h" 6 7 struct syscalls_enter_open_args { 8 unsigned long long unused; 9 long syscall_nr; 10 long filename_ptr; 11 long flags; 12 long mode; 13 }; 14 15 struct syscalls_exit_open_args { 16 unsigned long long unused; 17 long syscall_nr; 18 long ret; 19 }; 20 21 struct bpf_map_def SEC("maps") enter_open_map = { 22 .type = BPF_MAP_TYPE_ARRAY, 23 .key_size = sizeof(u32), 24 .value_size = sizeof(u32), 25 .max_entries = 1, 26 }; 27 28 struct bpf_map_def SEC("maps") exit_open_map = { 29 .type = BPF_MAP_TYPE_ARRAY, 30 .key_size = sizeof(u32), 31 .value_size = sizeof(u32), 32 .max_entries = 1, 33 }; 34 35 static __always_inline void count(void *map) 36 { 37 u32 key = 0; 38 u32 *value, init_val = 1; 39 40 value = bpf_map_lookup_elem(map, &key); 41 if (value) 42 *value += 1; 43 else 44 bpf_map_update_elem(map, &key, &init_val, BPF_NOEXIST); 45 } 46 47 SEC("tracepoint/syscalls/sys_enter_open") 48 int trace_enter_open(struct syscalls_enter_open_args *ctx) 49 { 50 count((void *)&enter_open_map); 51 return 0; 52 } 53 54 SEC("tracepoint/syscalls/sys_exit_open") 55 int trace_enter_exit(struct syscalls_exit_open_args *ctx) 56 { 57 count((void *)&exit_open_map); 58 return 0; 59 } 60