1 // SPDX-License-Identifier: GPL-2.0-only 2 /* Copyright (c) 2016 Facebook 3 */ 4 #include <linux/unistd.h> 5 #include <linux/bpf.h> 6 7 #include <stdlib.h> 8 #include <stdio.h> 9 #include <unistd.h> 10 #include <string.h> 11 #include <errno.h> 12 13 #include <bpf/bpf.h> 14 15 static void usage(void) 16 { 17 printf("Usage: tc_l2_ipip_redirect [...]\n"); 18 printf(" -U <file> Update an already pinned BPF array\n"); 19 printf(" -i <ifindex> Interface index\n"); 20 printf(" -h Display this help\n"); 21 } 22 23 int main(int argc, char **argv) 24 { 25 const char *pinned_file = NULL; 26 int ifindex = -1; 27 int array_key = 0; 28 int array_fd = -1; 29 int ret = -1; 30 int opt; 31 32 while ((opt = getopt(argc, argv, "F:U:i:")) != -1) { 33 switch (opt) { 34 /* General args */ 35 case 'U': 36 pinned_file = optarg; 37 break; 38 case 'i': 39 ifindex = atoi(optarg); 40 break; 41 default: 42 usage(); 43 goto out; 44 } 45 } 46 47 if (ifindex < 0 || !pinned_file) { 48 usage(); 49 goto out; 50 } 51 52 array_fd = bpf_obj_get(pinned_file); 53 if (array_fd < 0) { 54 fprintf(stderr, "bpf_obj_get(%s): %s(%d)\n", 55 pinned_file, strerror(errno), errno); 56 goto out; 57 } 58 59 /* bpf_tunnel_key.remote_ipv4 expects host byte orders */ 60 ret = bpf_map_update_elem(array_fd, &array_key, &ifindex, 0); 61 if (ret) { 62 perror("bpf_map_update_elem"); 63 goto out; 64 } 65 66 out: 67 if (array_fd != -1) 68 close(array_fd); 69 return ret; 70 } 71