blob: a9277b118c330b09f3c253785d20999d02c6410f [file] [log] [blame]
// SPDX-License-Identifier: GPL-2.0
/* eBPF example program:
*
* - Loads eBPF program
*
* The eBPF program loads a filter from file and attaches the
* program to a cgroup using BPF_PROG_ATTACH
*/
#define _GNU_SOURCE
#include <stdio.h>
#include <stdlib.h>
#include <stddef.h>
#include <string.h>
#include <unistd.h>
#include <assert.h>
#include <errno.h>
#include <fcntl.h>
#include <net/if.h>
#include <linux/bpf.h>
#include <bpf/bpf.h>
#include "bpf_insn.h"
#include "bpf_load.h"
static int usage(const char *argv0)
{
printf("Usage: %s cg-path filter-path [filter-id]\n", argv0);
return EXIT_FAILURE;
}
int main(int argc, char **argv)
{
int cg_fd, ret, filter_id = 0;
if (argc < 3)
return usage(argv[0]);
cg_fd = open(argv[1], O_DIRECTORY | O_RDONLY);
if (cg_fd < 0) {
printf("Failed to open cgroup path: '%s'\n", strerror(errno));
return EXIT_FAILURE;
}
if (load_bpf_file(argv[2]))
return EXIT_FAILURE;
printf("Output from kernel verifier:\n%s\n-------\n", bpf_log_buf);
if (argc > 3)
filter_id = atoi(argv[3]);
if (filter_id >= prog_cnt) {
printf("Invalid program id; program not found in file\n");
return EXIT_FAILURE;
}
ret = bpf_prog_attach(prog_fd[filter_id], cg_fd,
BPF_CGROUP_INET_SOCK_CREATE, 0);
if (ret < 0) {
printf("Failed to attach prog to cgroup: '%s'\n",
strerror(errno));
return EXIT_FAILURE;
}
return EXIT_SUCCESS;
}