/* Copyright (c) 2016 Facebook * * This program is free software; you can redistribute it and/or * modify it under the terms of version 2 of the GNU General Public * License as published by the Free Software Foundation. */ #include <linux/unistd.h> #include <linux/bpf.h> #include <stdlib.h> #include <stdio.h> #include <unistd.h> #include <string.h> #include <errno.h> #include <bpf/bpf.h> static void usage(void) { printf("Usage: tc_l2_ipip_redirect [...]\n"); printf(" -U <file> Update an already pinned BPF array\n"); printf(" -i <ifindex> Interface index\n"); printf(" -h Display this help\n"); } int main(int argc, char **argv) { const char *pinned_file = NULL; int ifindex = -1; int array_key = 0; int array_fd = -1; int ret = -1; int opt; while ((opt = getopt(argc, argv, "F:U:i:")) != -1) { switch (opt) { /* General args */ case 'U': pinned_file = optarg; break; case 'i': ifindex = atoi(optarg); break; default: usage(); goto out; } } if (ifindex < 0 || !pinned_file) { usage(); goto out; } array_fd = bpf_obj_get(pinned_file); if (array_fd < 0) { fprintf(stderr, "bpf_obj_get(%s): %s(%d)\n", pinned_file, strerror(errno), errno); goto out; } /* bpf_tunnel_key.remote_ipv4 expects host byte orders */ ret = bpf_map_update_elem(array_fd, &array_key, &ifindex, 0); if (ret) { perror("bpf_map_update_elem"); goto out; } out: if (array_fd != -1) close(array_fd); return ret; }