1 // SPDX-License-Identifier: GPL-2.0 2 /* Copyright (c) 2017-18 David Ahern <dsahern@gmail.com> 3 * 4 * This program is free software; you can redistribute it and/or 5 * modify it under the terms of version 2 of the GNU General Public 6 * License as published by the Free Software Foundation. 7 * 8 * This program is distributed in the hope that it will be useful, but 9 * WITHOUT ANY WARRANTY; without even the implied warranty of 10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 11 * General Public License for more details. 12 */ 13 14 #include <linux/bpf.h> 15 #include <linux/if_link.h> 16 #include <linux/limits.h> 17 #include <net/if.h> 18 #include <errno.h> 19 #include <stdio.h> 20 #include <stdlib.h> 21 #include <stdbool.h> 22 #include <string.h> 23 #include <unistd.h> 24 #include <fcntl.h> 25 #include <libgen.h> 26 27 #include "bpf_load.h" 28 #include "bpf_util.h" 29 #include <bpf/bpf.h> 30 31 32 static int do_attach(int idx, int fd, const char *name) 33 { 34 int err; 35 36 err = bpf_set_link_xdp_fd(idx, fd, 0); 37 if (err < 0) 38 printf("ERROR: failed to attach program to %s\n", name); 39 40 return err; 41 } 42 43 static int do_detach(int idx, const char *name) 44 { 45 int err; 46 47 err = bpf_set_link_xdp_fd(idx, -1, 0); 48 if (err < 0) 49 printf("ERROR: failed to detach program from %s\n", name); 50 51 return err; 52 } 53 54 static void usage(const char *prog) 55 { 56 fprintf(stderr, 57 "usage: %s [OPTS] interface-list\n" 58 "\nOPTS:\n" 59 " -d detach program\n" 60 " -D direct table lookups (skip fib rules)\n", 61 prog); 62 } 63 64 int main(int argc, char **argv) 65 { 66 char filename[PATH_MAX]; 67 int opt, i, idx, err; 68 int prog_id = 0; 69 int attach = 1; 70 int ret = 0; 71 72 while ((opt = getopt(argc, argv, ":dD")) != -1) { 73 switch (opt) { 74 case 'd': 75 attach = 0; 76 break; 77 case 'D': 78 prog_id = 1; 79 break; 80 default: 81 usage(basename(argv[0])); 82 return 1; 83 } 84 } 85 86 if (optind == argc) { 87 usage(basename(argv[0])); 88 return 1; 89 } 90 91 if (attach) { 92 snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]); 93 94 if (access(filename, O_RDONLY) < 0) { 95 printf("error accessing file %s: %s\n", 96 filename, strerror(errno)); 97 return 1; 98 } 99 100 if (load_bpf_file(filename)) { 101 printf("%s", bpf_log_buf); 102 return 1; 103 } 104 105 if (!prog_fd[prog_id]) { 106 printf("load_bpf_file: %s\n", strerror(errno)); 107 return 1; 108 } 109 } 110 if (attach) { 111 for (i = 1; i < 64; ++i) 112 bpf_map_update_elem(map_fd[0], &i, &i, 0); 113 } 114 115 for (i = optind; i < argc; ++i) { 116 idx = if_nametoindex(argv[i]); 117 if (!idx) 118 idx = strtoul(argv[i], NULL, 0); 119 120 if (!idx) { 121 fprintf(stderr, "Invalid arg\n"); 122 return 1; 123 } 124 if (!attach) { 125 err = do_detach(idx, argv[i]); 126 if (err) 127 ret = err; 128 } else { 129 err = do_attach(idx, prog_fd[prog_id], argv[i]); 130 if (err) 131 ret = err; 132 } 133 } 134 135 return ret; 136 } 137