1b2441318SGreg Kroah-Hartman // SPDX-License-Identifier: GPL-2.0 2554ae6e7SDavid Ahern /* eBPF example program: 3554ae6e7SDavid Ahern * 4554ae6e7SDavid Ahern * - Loads eBPF program 5554ae6e7SDavid Ahern * 6554ae6e7SDavid Ahern * The eBPF program loads a filter from file and attaches the 7554ae6e7SDavid Ahern * program to a cgroup using BPF_PROG_ATTACH 8554ae6e7SDavid Ahern */ 9554ae6e7SDavid Ahern 10554ae6e7SDavid Ahern #define _GNU_SOURCE 11554ae6e7SDavid Ahern 12554ae6e7SDavid Ahern #include <stdio.h> 13554ae6e7SDavid Ahern #include <stdlib.h> 14554ae6e7SDavid Ahern #include <stddef.h> 15554ae6e7SDavid Ahern #include <string.h> 16554ae6e7SDavid Ahern #include <unistd.h> 17554ae6e7SDavid Ahern #include <assert.h> 18554ae6e7SDavid Ahern #include <errno.h> 19554ae6e7SDavid Ahern #include <fcntl.h> 20554ae6e7SDavid Ahern #include <net/if.h> 21554ae6e7SDavid Ahern #include <linux/bpf.h> 228d930450SJakub Kicinski #include <bpf/bpf.h> 23554ae6e7SDavid Ahern 248d930450SJakub Kicinski #include "bpf_insn.h" 25554ae6e7SDavid Ahern #include "bpf_load.h" 26554ae6e7SDavid Ahern 27554ae6e7SDavid Ahern static int usage(const char *argv0) 28554ae6e7SDavid Ahern { 29554ae6e7SDavid Ahern printf("Usage: %s cg-path filter-path [filter-id]\n", argv0); 30554ae6e7SDavid Ahern return EXIT_FAILURE; 31554ae6e7SDavid Ahern } 32554ae6e7SDavid Ahern 33554ae6e7SDavid Ahern int main(int argc, char **argv) 34554ae6e7SDavid Ahern { 35554ae6e7SDavid Ahern int cg_fd, ret, filter_id = 0; 36554ae6e7SDavid Ahern 37554ae6e7SDavid Ahern if (argc < 3) 38554ae6e7SDavid Ahern return usage(argv[0]); 39554ae6e7SDavid Ahern 40554ae6e7SDavid Ahern cg_fd = open(argv[1], O_DIRECTORY | O_RDONLY); 41554ae6e7SDavid Ahern if (cg_fd < 0) { 42554ae6e7SDavid Ahern printf("Failed to open cgroup path: '%s'\n", strerror(errno)); 43554ae6e7SDavid Ahern return EXIT_FAILURE; 44554ae6e7SDavid Ahern } 45554ae6e7SDavid Ahern 46554ae6e7SDavid Ahern if (load_bpf_file(argv[2])) 47554ae6e7SDavid Ahern return EXIT_FAILURE; 48554ae6e7SDavid Ahern 49554ae6e7SDavid Ahern printf("Output from kernel verifier:\n%s\n-------\n", bpf_log_buf); 50554ae6e7SDavid Ahern 51554ae6e7SDavid Ahern if (argc > 3) 52554ae6e7SDavid Ahern filter_id = atoi(argv[3]); 53554ae6e7SDavid Ahern 54*ee583014SDan Carpenter if (filter_id >= prog_cnt) { 55554ae6e7SDavid Ahern printf("Invalid program id; program not found in file\n"); 56554ae6e7SDavid Ahern return EXIT_FAILURE; 57554ae6e7SDavid Ahern } 58554ae6e7SDavid Ahern 59554ae6e7SDavid Ahern ret = bpf_prog_attach(prog_fd[filter_id], cg_fd, 607f677633SAlexei Starovoitov BPF_CGROUP_INET_SOCK_CREATE, 0); 61554ae6e7SDavid Ahern if (ret < 0) { 62554ae6e7SDavid Ahern printf("Failed to attach prog to cgroup: '%s'\n", 63554ae6e7SDavid Ahern strerror(errno)); 64554ae6e7SDavid Ahern return EXIT_FAILURE; 65554ae6e7SDavid Ahern } 66554ae6e7SDavid Ahern 67554ae6e7SDavid Ahern return EXIT_SUCCESS; 68554ae6e7SDavid Ahern } 69