1 // SPDX-License-Identifier: GPL-2.0 2 // Copyright (c) 2019 Facebook 3 #include <linux/bpf.h> 4 #include <linux/version.h> 5 #include "bpf_helpers.h" 6 7 struct bpf_map_def SEC("maps") info_map = { 8 .type = BPF_MAP_TYPE_ARRAY, 9 .key_size = sizeof(__u32), 10 .value_size = sizeof(__u64), 11 .max_entries = 1, 12 }; 13 14 BPF_ANNOTATE_KV_PAIR(info_map, __u32, __u64); 15 16 struct bpf_map_def SEC("maps") status_map = { 17 .type = BPF_MAP_TYPE_ARRAY, 18 .key_size = sizeof(__u32), 19 .value_size = sizeof(__u64), 20 .max_entries = 1, 21 }; 22 23 BPF_ANNOTATE_KV_PAIR(status_map, __u32, __u64); 24 25 SEC("send_signal_demo") 26 int bpf_send_signal_test(void *ctx) 27 { 28 __u64 *info_val, *status_val; 29 __u32 key = 0, pid, sig; 30 int ret; 31 32 status_val = bpf_map_lookup_elem(&status_map, &key); 33 if (!status_val || *status_val != 0) 34 return 0; 35 36 info_val = bpf_map_lookup_elem(&info_map, &key); 37 if (!info_val || *info_val == 0) 38 return 0; 39 40 sig = *info_val >> 32; 41 pid = *info_val & 0xffffFFFF; 42 43 if ((bpf_get_current_pid_tgid() >> 32) == pid) { 44 ret = bpf_send_signal(sig); 45 if (ret == 0) 46 *status_val = 1; 47 } 48 49 return 0; 50 } 51 char __license[] SEC("license") = "GPL"; 52