+++ /dev/null
-// SPDX-License-Identifier: GPL-2.0
-#include <linux/ptrace.h>
-#include <linux/version.h>
-#include <uapi/linux/bpf.h>
-#include <bpf/bpf_helpers.h>
-
-#define SAMPLE_SIZE 64ul
-
-struct {
- __uint(type, BPF_MAP_TYPE_PERF_EVENT_ARRAY);
- __uint(key_size, sizeof(int));
- __uint(value_size, sizeof(u32));
-} my_map SEC(".maps");
-
-SEC("xdp_sample")
-int xdp_sample_prog(struct xdp_md *ctx)
-{
- void *data_end = (void *)(long)ctx->data_end;
- void *data = (void *)(long)ctx->data;
-
- /* Metadata will be in the perf event before the packet data. */
- struct S {
- u16 cookie;
- u16 pkt_len;
- } __packed metadata;
-
- if (data < data_end) {
- /* The XDP perf_event_output handler will use the upper 32 bits
- * of the flags argument as a number of bytes to include of the
- * packet payload in the event data. If the size is too big, the
- * call to bpf_perf_event_output will fail and return -EFAULT.
- *
- * See bpf_xdp_event_output in net/core/filter.c.
- *
- * The BPF_F_CURRENT_CPU flag means that the event output fd
- * will be indexed by the CPU number in the event map.
- */
- u64 flags = BPF_F_CURRENT_CPU;
- u16 sample_size;
- int ret;
-
- metadata.cookie = 0xdead;
- metadata.pkt_len = (u16)(data_end - data);
- sample_size = min(metadata.pkt_len, SAMPLE_SIZE);
- flags |= (u64)sample_size << 32;
-
- ret = bpf_perf_event_output(ctx, &my_map, flags,
- &metadata, sizeof(metadata));
- if (ret)
- bpf_printk("perf_event_output failed: %d\n", ret);
- }
-
- return XDP_PASS;
-}
-
-char _license[] SEC("license") = "GPL";
-u32 _version SEC("version") = LINUX_VERSION_CODE;
+++ /dev/null
-// 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 <bpf/libbpf.h>
-#include <bpf/bpf.h>
-#include <libgen.h>
-#include <linux/if_link.h>
-
-#include "perf-sys.h"
-
-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_xdp_attach(idx, fd, xdp_flags, NULL);
- if (err < 0) {
- printf("ERROR: failed to attach program to %s\n", name);
- return err;
- }
-
- err = bpf_prog_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_xdp_query_id(idx, xdp_flags, &curr_prog_id);
- if (err) {
- printf("bpf_xdp_query_id failed\n");
- return err;
- }
- if (prog_id == curr_prog_id) {
- err = bpf_xdp_detach(idx, xdp_flags, NULL);
- 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"
- " -S use skb-mode\n",
- __func__, prog);
-}
-
-int main(int argc, char **argv)
-{
- const char *optstr = "FS";
- int prog_fd, map_fd, opt;
- struct bpf_program *prog;
- 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;
- }
-
- snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
-
- obj = bpf_object__open_file(filename, NULL);
- if (libbpf_get_error(obj))
- return 1;
-
- prog = bpf_object__next_program(obj, NULL);
- bpf_program__set_type(prog, BPF_PROG_TYPE_XDP);
-
- err = bpf_object__load(obj);
- if (err)
- return 1;
-
- prog_fd = bpf_program__fd(prog);
-
- map = bpf_object__next_map(obj, NULL);
- 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 = perf_buffer__new(map_fd, 8, print_bpf_output, NULL, NULL, NULL);
- 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;
-}