samples/bpf/xdp_redirect_map_user.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /* Copyright (c) 2017 Covalent IO, Inc. http://covalent.io
   3  */
   4 static const char *__doc__ =
   5 "XDP redirect tool, using BPF_MAP_TYPE_DEVMAP\n"
   6 "Usage: xdp_redirect_map <IFINDEX|IFNAME>_IN <IFINDEX|IFNAME>_OUT\n";
   7
   8 #include <linux/bpf.h>
   9 #include <linux/if_link.h>
  10 #include <assert.h>
  11 #include <errno.h>
  12 #include <signal.h>
  13 #include <stdio.h>
  14 #include <stdlib.h>
  15 #include <stdbool.h>
  16 #include <string.h>
  17 #include <net/if.h>
  18 #include <unistd.h>
  19 #include <libgen.h>
  20 #include <getopt.h>
  21 #include <bpf/bpf.h>
  22 #include <bpf/libbpf.h>
  23 #include "bpf_util.h"
  24 #include "xdp_sample_user.h"
  25 #include "xdp_redirect_map.skel.h"
  26
  27 static int mask = SAMPLE_RX_CNT | SAMPLE_REDIRECT_ERR_MAP_CNT |
  28                   SAMPLE_EXCEPTION_CNT | SAMPLE_DEVMAP_XMIT_CNT_MULTI;
  29
  30 DEFINE_SAMPLE_INIT(xdp_redirect_map);
  31
  32 static const struct option long_options[] = {
  33         { "help", no_argument, NULL, 'h' },
  34         { "skb-mode", no_argument, NULL, 'S' },
  35         { "force", no_argument, NULL, 'F' },
  36         { "load-egress", no_argument, NULL, 'X' },
  37         { "stats", no_argument, NULL, 's' },
  38         { "interval", required_argument, NULL, 'i' },
  39         { "verbose", no_argument, NULL, 'v' },
  40         {}
  41 };
  42
  43 int main(int argc, char **argv)
  44 {
  45         struct bpf_devmap_val devmap_val = {};
  46         bool xdp_devmap_attached = false;
  47         struct xdp_redirect_map *skel;
  48         char str[2 * IF_NAMESIZE + 1];
  49         char ifname_out[IF_NAMESIZE];
  50         struct bpf_map *tx_port_map;
  51         char ifname_in[IF_NAMESIZE];
  52         int ifindex_in, ifindex_out;
  53         unsigned long interval = 2;
  54         int ret = EXIT_FAIL_OPTION;
  55         struct bpf_program *prog;
  56         bool generic = false;
  57         bool force = false;
  58         bool tried = false;
  59         bool error = true;
  60         int opt, key = 0;
  61
  62         while ((opt = getopt_long(argc, argv, "hSFXi:vs",
  63                                   long_options, NULL)) != -1) {
  64                 switch (opt) {
  65                 case 'S':
  66                         generic = true;
  67                         /* devmap_xmit tracepoint not available */
  68                         mask &= ~(SAMPLE_DEVMAP_XMIT_CNT |
  69                                   SAMPLE_DEVMAP_XMIT_CNT_MULTI);
  70                         break;
  71                 case 'F':
  72                         force = true;
  73                         break;
  74                 case 'X':
  75                         xdp_devmap_attached = true;
  76                         break;
  77                 case 'i':
  78                         interval = strtoul(optarg, NULL, 0);
  79                         break;
  80                 case 'v':
  81                         sample_switch_mode();
  82                         break;
  83                 case 's':
  84                         mask |= SAMPLE_REDIRECT_MAP_CNT;
  85                         break;
  86                 case 'h':
  87                         error = false;
  88                 default:
  89                         sample_usage(argv, long_options, __doc__, mask, error);
  90                         return ret;
  91                 }
  92         }
  93
  94         if (argc <= optind + 1) {
  95                 sample_usage(argv, long_options, __doc__, mask, true);
  96                 goto end;
  97         }
  98
  99         ifindex_in = if_nametoindex(argv[optind]);
 100         if (!ifindex_in)
 101                 ifindex_in = strtoul(argv[optind], NULL, 0);
 102
 103         ifindex_out = if_nametoindex(argv[optind + 1]);
 104         if (!ifindex_out)
 105                 ifindex_out = strtoul(argv[optind + 1], NULL, 0);
 106
 107         if (!ifindex_in || !ifindex_out) {
 108                 fprintf(stderr, "Bad interface index or name\n");
 109                 sample_usage(argv, long_options, __doc__, mask, true);
 110                 goto end;
 111         }
 112
 113         skel = xdp_redirect_map__open();
 114         if (!skel) {
 115                 fprintf(stderr, "Failed to xdp_redirect_map__open: %s\n",
 116                         strerror(errno));
 117                 ret = EXIT_FAIL_BPF;
 118                 goto end;
 119         }
 120
 121         ret = sample_init_pre_load(skel);
 122         if (ret < 0) {
 123                 fprintf(stderr, "Failed to sample_init_pre_load: %s\n", strerror(-ret));
 124                 ret = EXIT_FAIL_BPF;
 125                 goto end_destroy;
 126         }
 127
 128         /* Load 2nd xdp prog on egress. */
 129         if (xdp_devmap_attached) {
 130                 ret = get_mac_addr(ifindex_out, skel->rodata->tx_mac_addr);
 131                 if (ret < 0) {
 132                         fprintf(stderr, "Failed to get interface %d mac address: %s\n",
 133                                 ifindex_out, strerror(-ret));
 134                         ret = EXIT_FAIL;
 135                         goto end_destroy;
 136                 }
 137         }
 138
 139         skel->rodata->from_match[0] = ifindex_in;
 140         skel->rodata->to_match[0] = ifindex_out;
 141
 142         ret = xdp_redirect_map__load(skel);
 143         if (ret < 0) {
 144                 fprintf(stderr, "Failed to xdp_redirect_map__load: %s\n",
 145                         strerror(errno));
 146                 ret = EXIT_FAIL_BPF;
 147                 goto end_destroy;
 148         }
 149
 150         ret = sample_init(skel, mask);
 151         if (ret < 0) {
 152                 fprintf(stderr, "Failed to initialize sample: %s\n", strerror(-ret));
 153                 ret = EXIT_FAIL;
 154                 goto end_destroy;
 155         }
 156
 157         prog = skel->progs.xdp_redirect_map_native;
 158         tx_port_map = skel->maps.tx_port_native;
 159 restart:
 160         if (sample_install_xdp(prog, ifindex_in, generic, force) < 0) {
 161                 /* First try with struct bpf_devmap_val as value for generic
 162                  * mode, then fallback to sizeof(int) for older kernels.
 163                  */
 164                 fprintf(stderr,
 165                         "Trying fallback to sizeof(int) as value_size for devmap in generic mode\n");
 166                 if (generic && !tried) {
 167                         prog = skel->progs.xdp_redirect_map_general;
 168                         tx_port_map = skel->maps.tx_port_general;
 169                         tried = true;
 170                         goto restart;
 171                 }
 172                 ret = EXIT_FAIL_XDP;
 173                 goto end_destroy;
 174         }
 175
 176         /* Loading dummy XDP prog on out-device */
 177         sample_install_xdp(skel->progs.xdp_redirect_dummy_prog, ifindex_out, generic, force);
 178
 179         devmap_val.ifindex = ifindex_out;
 180         if (xdp_devmap_attached)
 181                 devmap_val.bpf_prog.fd = bpf_program__fd(skel->progs.xdp_redirect_map_egress);
 182         ret = bpf_map_update_elem(bpf_map__fd(tx_port_map), &key, &devmap_val, 0);
 183         if (ret < 0) {
 184                 fprintf(stderr, "Failed to update devmap value: %s\n",
 185                         strerror(errno));
 186                 ret = EXIT_FAIL_BPF;
 187                 goto end_destroy;
 188         }
 189
 190         ret = EXIT_FAIL;
 191         if (!if_indextoname(ifindex_in, ifname_in)) {
 192                 fprintf(stderr, "Failed to if_indextoname for %d: %s\n", ifindex_in,
 193                         strerror(errno));
 194                 goto end_destroy;
 195         }
 196
 197         if (!if_indextoname(ifindex_out, ifname_out)) {
 198                 fprintf(stderr, "Failed to if_indextoname for %d: %s\n", ifindex_out,
 199                         strerror(errno));
 200                 goto end_destroy;
 201         }
 202
 203         safe_strncpy(str, get_driver_name(ifindex_in), sizeof(str));
 204         printf("Redirecting from %s (ifindex %d; driver %s) to %s (ifindex %d; driver %s)\n",
 205                ifname_in, ifindex_in, str, ifname_out, ifindex_out, get_driver_name(ifindex_out));
 206         snprintf(str, sizeof(str), "%s->%s", ifname_in, ifname_out);
 207
 208         ret = sample_run(interval, NULL, NULL);
 209         if (ret < 0) {
 210                 fprintf(stderr, "Failed during sample run: %s\n", strerror(-ret));
 211                 ret = EXIT_FAIL;
 212                 goto end_destroy;
 213         }
 214         ret = EXIT_OK;
 215 end_destroy:
 216         xdp_redirect_map__destroy(skel);
 217 end:
 218         sample_exit(ret);
 219 }