204 lines
4.1 KiB
C
204 lines
4.1 KiB
C
// SPDX-License-Identifier: GPL-2.0
|
|
#include <stdio.h>
|
|
#include <stdlib.h>
|
|
#include <string.h>
|
|
#include <linux/perf_event.h>
|
|
#include <linux/bpf.h>
|
|
#include <net/if.h>
|
|
#include <errno.h>
|
|
#include <assert.h>
|
|
#include <sys/sysinfo.h>
|
|
#include <sys/ioctl.h>
|
|
#include <signal.h>
|
|
#include <libbpf.h>
|
|
#include <bpf/bpf.h>
|
|
#include <sys/resource.h>
|
|
#include <libgen.h>
|
|
#include <linux/if_link.h>
|
|
|
|
#include "perf-sys.h"
|
|
|
|
#define MAX_CPUS 128
|
|
static int if_idx;
|
|
static char *if_name;
|
|
static __u32 xdp_flags = XDP_FLAGS_UPDATE_IF_NOEXIST;
|
|
static __u32 prog_id;
|
|
static struct perf_buffer *pb = NULL;
|
|
|
|
static int do_attach(int idx, int fd, const char *name)
|
|
{
|
|
struct bpf_prog_info info = {};
|
|
__u32 info_len = sizeof(info);
|
|
int err;
|
|
|
|
err = bpf_set_link_xdp_fd(idx, fd, xdp_flags);
|
|
if (err < 0) {
|
|
printf("ERROR: failed to attach program to %s\n", name);
|
|
return err;
|
|
}
|
|
|
|
err = bpf_obj_get_info_by_fd(fd, &info, &info_len);
|
|
if (err) {
|
|
printf("can't get prog info - %s\n", strerror(errno));
|
|
return err;
|
|
}
|
|
prog_id = info.id;
|
|
|
|
return err;
|
|
}
|
|
|
|
static int do_detach(int idx, const char *name)
|
|
{
|
|
__u32 curr_prog_id = 0;
|
|
int err = 0;
|
|
|
|
err = bpf_get_link_xdp_id(idx, &curr_prog_id, xdp_flags);
|
|
if (err) {
|
|
printf("bpf_get_link_xdp_id failed\n");
|
|
return err;
|
|
}
|
|
if (prog_id == curr_prog_id) {
|
|
err = bpf_set_link_xdp_fd(idx, -1, xdp_flags);
|
|
if (err < 0)
|
|
printf("ERROR: failed to detach prog from %s\n", name);
|
|
} else if (!curr_prog_id) {
|
|
printf("couldn't find a prog id on a %s\n", name);
|
|
} else {
|
|
printf("program on interface changed, not removing\n");
|
|
}
|
|
|
|
return err;
|
|
}
|
|
|
|
#define SAMPLE_SIZE 64
|
|
|
|
static void print_bpf_output(void *ctx, int cpu, void *data, __u32 size)
|
|
{
|
|
struct {
|
|
__u16 cookie;
|
|
__u16 pkt_len;
|
|
__u8 pkt_data[SAMPLE_SIZE];
|
|
} __packed *e = data;
|
|
int i;
|
|
|
|
if (e->cookie != 0xdead) {
|
|
printf("BUG cookie %x sized %d\n", e->cookie, size);
|
|
return;
|
|
}
|
|
|
|
printf("Pkt len: %-5d bytes. Ethernet hdr: ", e->pkt_len);
|
|
for (i = 0; i < 14 && i < e->pkt_len; i++)
|
|
printf("%02x ", e->pkt_data[i]);
|
|
printf("\n");
|
|
}
|
|
|
|
static void sig_handler(int signo)
|
|
{
|
|
do_detach(if_idx, if_name);
|
|
perf_buffer__free(pb);
|
|
exit(0);
|
|
}
|
|
|
|
static void usage(const char *prog)
|
|
{
|
|
fprintf(stderr,
|
|
"%s: %s [OPTS] <ifname|ifindex>\n\n"
|
|
"OPTS:\n"
|
|
" -F force loading prog\n",
|
|
__func__, prog);
|
|
}
|
|
|
|
int main(int argc, char **argv)
|
|
{
|
|
struct rlimit r = {RLIM_INFINITY, RLIM_INFINITY};
|
|
struct bpf_prog_load_attr prog_load_attr = {
|
|
.prog_type = BPF_PROG_TYPE_XDP,
|
|
};
|
|
struct perf_buffer_opts pb_opts = {};
|
|
const char *optstr = "FS";
|
|
int prog_fd, map_fd, opt;
|
|
struct bpf_object *obj;
|
|
struct bpf_map *map;
|
|
char filename[256];
|
|
int ret, err;
|
|
|
|
while ((opt = getopt(argc, argv, optstr)) != -1) {
|
|
switch (opt) {
|
|
case 'F':
|
|
xdp_flags &= ~XDP_FLAGS_UPDATE_IF_NOEXIST;
|
|
break;
|
|
case 'S':
|
|
xdp_flags |= XDP_FLAGS_SKB_MODE;
|
|
break;
|
|
default:
|
|
usage(basename(argv[0]));
|
|
return 1;
|
|
}
|
|
}
|
|
|
|
if (!(xdp_flags & XDP_FLAGS_SKB_MODE))
|
|
xdp_flags |= XDP_FLAGS_DRV_MODE;
|
|
|
|
if (optind == argc) {
|
|
usage(basename(argv[0]));
|
|
return 1;
|
|
}
|
|
|
|
if (setrlimit(RLIMIT_MEMLOCK, &r)) {
|
|
perror("setrlimit(RLIMIT_MEMLOCK)");
|
|
return 1;
|
|
}
|
|
|
|
snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
|
|
prog_load_attr.file = filename;
|
|
|
|
if (bpf_prog_load_xattr(&prog_load_attr, &obj, &prog_fd))
|
|
return 1;
|
|
|
|
if (!prog_fd) {
|
|
printf("bpf_prog_load_xattr: %s\n", strerror(errno));
|
|
return 1;
|
|
}
|
|
|
|
map = bpf_map__next(NULL, obj);
|
|
if (!map) {
|
|
printf("finding a map in obj file failed\n");
|
|
return 1;
|
|
}
|
|
map_fd = bpf_map__fd(map);
|
|
|
|
if_idx = if_nametoindex(argv[optind]);
|
|
if (!if_idx)
|
|
if_idx = strtoul(argv[optind], NULL, 0);
|
|
|
|
if (!if_idx) {
|
|
fprintf(stderr, "Invalid ifname\n");
|
|
return 1;
|
|
}
|
|
if_name = argv[optind];
|
|
err = do_attach(if_idx, prog_fd, if_name);
|
|
if (err)
|
|
return err;
|
|
|
|
if (signal(SIGINT, sig_handler) ||
|
|
signal(SIGHUP, sig_handler) ||
|
|
signal(SIGTERM, sig_handler)) {
|
|
perror("signal");
|
|
return 1;
|
|
}
|
|
|
|
pb_opts.sample_cb = print_bpf_output;
|
|
pb = perf_buffer__new(map_fd, 8, &pb_opts);
|
|
err = libbpf_get_error(pb);
|
|
if (err) {
|
|
perror("perf_buffer setup failed");
|
|
return 1;
|
|
}
|
|
|
|
while ((ret = perf_buffer__poll(pb, 1000)) >= 0) {
|
|
}
|
|
|
|
kill(0, SIGINT);
|
|
return ret;
|
|
}
|