samples/bpf/xdp_router_ipv4_user.c

   1 /* Copyright (C) 2017 Cavium, Inc.
   2  *
   3  * This program is free software; you can redistribute it and/or modify it
   4  * under the terms of version 2 of the GNU General Public License
   5  * as published by the Free Software Foundation.
   6  */
   7 #include <linux/bpf.h>
   8 #include <linux/netlink.h>
   9 #include <linux/rtnetlink.h>
  10 #include <assert.h>
  11 #include <errno.h>
  12 #include <signal.h>
  13 #include <stdio.h>
  14 #include <stdlib.h>
  15 #include <string.h>
  16 #include <sys/socket.h>
  17 #include <unistd.h>
  18 #include <bpf/bpf.h>
  19 #include <arpa/inet.h>
  20 #include <fcntl.h>
  21 #include <poll.h>
  22 #include <net/if.h>
  23 #include <netdb.h>
  24 #include <sys/ioctl.h>
  25 #include <sys/syscall.h>
  26 #include "bpf_util.h"
  27 #include "bpf/libbpf.h"
  28 #include <sys/resource.h>
  29 #include <libgen.h>
  30
  31 int sock, sock_arp, flags = XDP_FLAGS_UPDATE_IF_NOEXIST;
  32 static int total_ifindex;
  33 static int *ifindex_list;
  34 static __u32 *prog_id_list;
  35 char buf[8192];
  36 static int lpm_map_fd;
  37 static int rxcnt_map_fd;
  38 static int arp_table_map_fd;
  39 static int exact_match_map_fd;
  40 static int tx_port_map_fd;
  41
  42 static int get_route_table(int rtm_family);
  43 static void int_exit(int sig)
  44 {
  45         __u32 prog_id = 0;
  46         int i = 0;
  47
  48         for (i = 0; i < total_ifindex; i++) {
  49                 if (bpf_get_link_xdp_id(ifindex_list[i], &prog_id, flags)) {
  50                         printf("bpf_get_link_xdp_id on iface %d failed\n",
  51                                ifindex_list[i]);
  52                         exit(1);
  53                 }
  54                 if (prog_id_list[i] == prog_id)
  55                         bpf_set_link_xdp_fd(ifindex_list[i], -1, flags);
  56                 else if (!prog_id)
  57                         printf("couldn't find a prog id on iface %d\n",
  58                                ifindex_list[i]);
  59                 else
  60                         printf("program on iface %d changed, not removing\n",
  61                                ifindex_list[i]);
  62                 prog_id = 0;
  63         }
  64         exit(0);
  65 }
  66
  67 static void close_and_exit(int sig)
  68 {
  69         close(sock);
  70         close(sock_arp);
  71
  72         int_exit(0);
  73 }
  74
  75 /* Get the mac address of the interface given interface name */
  76 static __be64 getmac(char *iface)
  77 {
  78         struct ifreq ifr;
  79         __be64 mac = 0;
  80         int fd, i;
  81
  82         fd = socket(AF_INET, SOCK_DGRAM, 0);
  83         ifr.ifr_addr.sa_family = AF_INET;
  84         strncpy(ifr.ifr_name, iface, IFNAMSIZ - 1);
  85         if (ioctl(fd, SIOCGIFHWADDR, &ifr) < 0) {
  86                 printf("ioctl failed leaving....\n");
  87                 return -1;
  88         }
  89         for (i = 0; i < 6 ; i++)
  90                 *((__u8 *)&mac + i) = (__u8)ifr.ifr_hwaddr.sa_data[i];
  91         close(fd);
  92         return mac;
  93 }
  94
  95 static int recv_msg(struct sockaddr_nl sock_addr, int sock)
  96 {
  97         struct nlmsghdr *nh;
  98         int len, nll = 0;
  99         char *buf_ptr;
 100
 101         buf_ptr = buf;
 102         while (1) {
 103                 len = recv(sock, buf_ptr, sizeof(buf) - nll, 0);
 104                 if (len < 0)
 105                         return len;
 106
 107                 nh = (struct nlmsghdr *)buf_ptr;
 108
 109                 if (nh->nlmsg_type == NLMSG_DONE)
 110                         break;
 111                 buf_ptr += len;
 112                 nll += len;
 113                 if ((sock_addr.nl_groups & RTMGRP_NEIGH) == RTMGRP_NEIGH)
 114                         break;
 115
 116                 if ((sock_addr.nl_groups & RTMGRP_IPV4_ROUTE) == RTMGRP_IPV4_ROUTE)
 117                         break;
 118         }
 119         return nll;
 120 }
 121
 122 /* Function to parse the route entry returned by netlink
 123  * Updates the route entry related map entries
 124  */
 125 static void read_route(struct nlmsghdr *nh, int nll)
 126 {
 127         char dsts[24], gws[24], ifs[16], dsts_len[24], metrics[24];
 128         struct bpf_lpm_trie_key *prefix_key;
 129         struct rtattr *rt_attr;
 130         struct rtmsg *rt_msg;
 131         int rtm_family;
 132         int rtl;
 133         int i;
 134         struct route_table {
 135                 int  dst_len, iface, metric;
 136                 char *iface_name;
 137                 __be32 dst, gw;
 138                 __be64 mac;
 139         } route;
 140         struct arp_table {
 141                 __be64 mac;
 142                 __be32 dst;
 143         };
 144
 145         struct direct_map {
 146                 struct arp_table arp;
 147                 int ifindex;
 148                 __be64 mac;
 149         } direct_entry;
 150
 151         if (nh->nlmsg_type == RTM_DELROUTE)
 152                 printf("DELETING Route entry\n");
 153         else if (nh->nlmsg_type == RTM_GETROUTE)
 154                 printf("READING Route entry\n");
 155         else if (nh->nlmsg_type == RTM_NEWROUTE)
 156                 printf("NEW Route entry\n");
 157         else
 158                 printf("%d\n", nh->nlmsg_type);
 159
 160         memset(&route, 0, sizeof(route));
 161         printf("Destination\t\tGateway\t\tGenmask\t\tMetric\t\tIface\n");
 162         for (; NLMSG_OK(nh, nll); nh = NLMSG_NEXT(nh, nll)) {
 163                 rt_msg = (struct rtmsg *)NLMSG_DATA(nh);
 164                 rtm_family = rt_msg->rtm_family;
 165                 if (rtm_family == AF_INET)
 166                         if (rt_msg->rtm_table != RT_TABLE_MAIN)
 167                                 continue;
 168                 rt_attr = (struct rtattr *)RTM_RTA(rt_msg);
 169                 rtl = RTM_PAYLOAD(nh);
 170
 171                 for (; RTA_OK(rt_attr, rtl); rt_attr = RTA_NEXT(rt_attr, rtl)) {
 172                         switch (rt_attr->rta_type) {
 173                         case NDA_DST:
 174                                 sprintf(dsts, "%u",
 175                                         (*((__be32 *)RTA_DATA(rt_attr))));
 176                                 break;
 177                         case RTA_GATEWAY:
 178                                 sprintf(gws, "%u",
 179                                         *((__be32 *)RTA_DATA(rt_attr)));
 180                                 break;
 181                         case RTA_OIF:
 182                                 sprintf(ifs, "%u",
 183                                         *((int *)RTA_DATA(rt_attr)));
 184                                 break;
 185                         case RTA_METRICS:
 186                                 sprintf(metrics, "%u",
 187                                         *((int *)RTA_DATA(rt_attr)));
 188                         default:
 189                                 break;
 190                         }
 191                 }
 192                 sprintf(dsts_len, "%d", rt_msg->rtm_dst_len);
 193                 route.dst = atoi(dsts);
 194                 route.dst_len = atoi(dsts_len);
 195                 route.gw = atoi(gws);
 196                 route.iface = atoi(ifs);
 197                 route.metric = atoi(metrics);
 198                 route.iface_name = alloca(sizeof(char *) * IFNAMSIZ);
 199                 route.iface_name = if_indextoname(route.iface, route.iface_name);
 200                 route.mac = getmac(route.iface_name);
 201                 if (route.mac == -1)
 202                         int_exit(0);
 203                 assert(bpf_map_update_elem(tx_port_map_fd,
 204                                            &route.iface, &route.iface, 0) == 0);
 205                 if (rtm_family == AF_INET) {
 206                         struct trie_value {
 207                                 __u8 prefix[4];
 208                                 __be64 value;
 209                                 int ifindex;
 210                                 int metric;
 211                                 __be32 gw;
 212                         } *prefix_value;
 213
 214                         prefix_key = alloca(sizeof(*prefix_key) + 3);
 215                         prefix_value = alloca(sizeof(*prefix_value));
 216
 217                         prefix_key->prefixlen = 32;
 218                         prefix_key->prefixlen = route.dst_len;
 219                         direct_entry.mac = route.mac & 0xffffffffffff;
 220                         direct_entry.ifindex = route.iface;
 221                         direct_entry.arp.mac = 0;
 222                         direct_entry.arp.dst = 0;
 223                         if (route.dst_len == 32) {
 224                                 if (nh->nlmsg_type == RTM_DELROUTE) {
 225                                         assert(bpf_map_delete_elem(exact_match_map_fd,
 226                                                                    &route.dst) == 0);
 227                                 } else {
 228                                         if (bpf_map_lookup_elem(arp_table_map_fd,
 229                                                                 &route.dst,
 230                                                                 &direct_entry.arp.mac) == 0)
 231                                                 direct_entry.arp.dst = route.dst;
 232                                         assert(bpf_map_update_elem(exact_match_map_fd,
 233                                                                    &route.dst,
 234                                                                    &direct_entry, 0) == 0);
 235                                 }
 236                         }
 237                         for (i = 0; i < 4; i++)
 238                                 prefix_key->data[i] = (route.dst >> i * 8) & 0xff;
 239
 240                         printf("%3d.%d.%d.%d\t\t%3x\t\t%d\t\t%d\t\t%s\n",
 241                                (int)prefix_key->data[0],
 242                                (int)prefix_key->data[1],
 243                                (int)prefix_key->data[2],
 244                                (int)prefix_key->data[3],
 245                                route.gw, route.dst_len,
 246                                route.metric,
 247                                route.iface_name);
 248                         if (bpf_map_lookup_elem(lpm_map_fd, prefix_key,
 249                                                 prefix_value) < 0) {
 250                                 for (i = 0; i < 4; i++)
 251                                         prefix_value->prefix[i] = prefix_key->data[i];
 252                                 prefix_value->value = route.mac & 0xffffffffffff;
 253                                 prefix_value->ifindex = route.iface;
 254                                 prefix_value->gw = route.gw;
 255                                 prefix_value->metric = route.metric;
 256
 257                                 assert(bpf_map_update_elem(lpm_map_fd,
 258                                                            prefix_key,
 259                                                            prefix_value, 0
 260                                                            ) == 0);
 261                         } else {
 262                                 if (nh->nlmsg_type == RTM_DELROUTE) {
 263                                         printf("deleting entry\n");
 264                                         printf("prefix key=%d.%d.%d.%d/%d",
 265                                                prefix_key->data[0],
 266                                                prefix_key->data[1],
 267                                                prefix_key->data[2],
 268                                                prefix_key->data[3],
 269                                                prefix_key->prefixlen);
 270                                         assert(bpf_map_delete_elem(lpm_map_fd,
 271                                                                    prefix_key
 272                                                                    ) == 0);
 273                                         /* Rereading the route table to check if
 274                                          * there is an entry with the same
 275                                          * prefix but a different metric as the
 276                                          * deleted enty.
 277                                          */
 278                                         get_route_table(AF_INET);
 279                                 } else if (prefix_key->data[0] ==
 280                                            prefix_value->prefix[0] &&
 281                                            prefix_key->data[1] ==
 282                                            prefix_value->prefix[1] &&
 283                                            prefix_key->data[2] ==
 284                                            prefix_value->prefix[2] &&
 285                                            prefix_key->data[3] ==
 286                                            prefix_value->prefix[3] &&
 287                                            route.metric >= prefix_value->metric) {
 288                                         continue;
 289                                 } else {
 290                                         for (i = 0; i < 4; i++)
 291                                                 prefix_value->prefix[i] =
 292                                                         prefix_key->data[i];
 293                                         prefix_value->value =
 294                                                 route.mac & 0xffffffffffff;
 295                                         prefix_value->ifindex = route.iface;
 296                                         prefix_value->gw = route.gw;
 297                                         prefix_value->metric = route.metric;
 298                                         assert(bpf_map_update_elem(lpm_map_fd,
 299                                                                    prefix_key,
 300                                                                    prefix_value,
 301                                                                    0) == 0);
 302                                 }
 303                         }
 304                 }
 305                 memset(&route, 0, sizeof(route));
 306                 memset(dsts, 0, sizeof(dsts));
 307                 memset(dsts_len, 0, sizeof(dsts_len));
 308                 memset(gws, 0, sizeof(gws));
 309                 memset(ifs, 0, sizeof(ifs));
 310                 memset(&route, 0, sizeof(route));
 311         }
 312 }
 313
 314 /* Function to read the existing route table  when the process is launched*/
 315 static int get_route_table(int rtm_family)
 316 {
 317         struct sockaddr_nl sa;
 318         struct nlmsghdr *nh;
 319         int sock, seq = 0;
 320         struct msghdr msg;
 321         struct iovec iov;
 322         int ret = 0;
 323         int nll;
 324
 325         struct {
 326                 struct nlmsghdr nl;
 327                 struct rtmsg rt;
 328                 char buf[8192];
 329         } req;
 330
 331         sock = socket(AF_NETLINK, SOCK_RAW, NETLINK_ROUTE);
 332         if (sock < 0) {
 333                 printf("open netlink socket: %s\n", strerror(errno));
 334                 return -1;
 335         }
 336         memset(&sa, 0, sizeof(sa));
 337         sa.nl_family = AF_NETLINK;
 338         if (bind(sock, (struct sockaddr *)&sa, sizeof(sa)) < 0) {
 339                 printf("bind to netlink: %s\n", strerror(errno));
 340                 ret = -1;
 341                 goto cleanup;
 342         }
 343         memset(&req, 0, sizeof(req));
 344         req.nl.nlmsg_len = NLMSG_LENGTH(sizeof(struct rtmsg));
 345         req.nl.nlmsg_flags = NLM_F_REQUEST | NLM_F_DUMP;
 346         req.nl.nlmsg_type = RTM_GETROUTE;
 347
 348         req.rt.rtm_family = rtm_family;
 349         req.rt.rtm_table = RT_TABLE_MAIN;
 350         req.nl.nlmsg_pid = 0;
 351         req.nl.nlmsg_seq = ++seq;
 352         memset(&msg, 0, sizeof(msg));
 353         iov.iov_base = (void *)&req.nl;
 354         iov.iov_len = req.nl.nlmsg_len;
 355         msg.msg_iov = &iov;
 356         msg.msg_iovlen = 1;
 357         ret = sendmsg(sock, &msg, 0);
 358         if (ret < 0) {
 359                 printf("send to netlink: %s\n", strerror(errno));
 360                 ret = -1;
 361                 goto cleanup;
 362         }
 363         memset(buf, 0, sizeof(buf));
 364         nll = recv_msg(sa, sock);
 365         if (nll < 0) {
 366                 printf("recv from netlink: %s\n", strerror(nll));
 367                 ret = -1;
 368                 goto cleanup;
 369         }
 370         nh = (struct nlmsghdr *)buf;
 371         read_route(nh, nll);
 372 cleanup:
 373         close(sock);
 374         return ret;
 375 }
 376
 377 /* Function to parse the arp entry returned by netlink
 378  * Updates the arp entry related map entries
 379  */
 380 static void read_arp(struct nlmsghdr *nh, int nll)
 381 {
 382         struct rtattr *rt_attr;
 383         char dsts[24], mac[24];
 384         struct ndmsg *rt_msg;
 385         int rtl, ndm_family;
 386
 387         struct arp_table {
 388                 __be64 mac;
 389                 __be32 dst;
 390         } arp_entry;
 391         struct direct_map {
 392                 struct arp_table arp;
 393                 int ifindex;
 394                 __be64 mac;
 395         } direct_entry;
 396
 397         if (nh->nlmsg_type == RTM_GETNEIGH)
 398                 printf("READING arp entry\n");
 399         printf("Address\tHwAddress\n");
 400         for (; NLMSG_OK(nh, nll); nh = NLMSG_NEXT(nh, nll)) {
 401                 rt_msg = (struct ndmsg *)NLMSG_DATA(nh);
 402                 rt_attr = (struct rtattr *)RTM_RTA(rt_msg);
 403                 ndm_family = rt_msg->ndm_family;
 404                 rtl = RTM_PAYLOAD(nh);
 405                 for (; RTA_OK(rt_attr, rtl); rt_attr = RTA_NEXT(rt_attr, rtl)) {
 406                         switch (rt_attr->rta_type) {
 407                         case NDA_DST:
 408                                 sprintf(dsts, "%u",
 409                                         *((__be32 *)RTA_DATA(rt_attr)));
 410                                 break;
 411                         case NDA_LLADDR:
 412                                 sprintf(mac, "%lld",
 413                                         *((__be64 *)RTA_DATA(rt_attr)));
 414                                 break;
 415                         default:
 416                                 break;
 417                         }
 418                 }
 419                 arp_entry.dst = atoi(dsts);
 420                 arp_entry.mac = atol(mac);
 421                 printf("%x\t\t%llx\n", arp_entry.dst, arp_entry.mac);
 422                 if (ndm_family == AF_INET) {
 423                         if (bpf_map_lookup_elem(exact_match_map_fd,
 424                                                 &arp_entry.dst,
 425                                                 &direct_entry) == 0) {
 426                                 if (nh->nlmsg_type == RTM_DELNEIGH) {
 427                                         direct_entry.arp.dst = 0;
 428                                         direct_entry.arp.mac = 0;
 429                                 } else if (nh->nlmsg_type == RTM_NEWNEIGH) {
 430                                         direct_entry.arp.dst = arp_entry.dst;
 431                                         direct_entry.arp.mac = arp_entry.mac;
 432                                 }
 433                                 assert(bpf_map_update_elem(exact_match_map_fd,
 434                                                            &arp_entry.dst,
 435                                                            &direct_entry, 0
 436                                                            ) == 0);
 437                                 memset(&direct_entry, 0, sizeof(direct_entry));
 438                         }
 439                         if (nh->nlmsg_type == RTM_DELNEIGH) {
 440                                 assert(bpf_map_delete_elem(arp_table_map_fd,
 441                                                            &arp_entry.dst) == 0);
 442                         } else if (nh->nlmsg_type == RTM_NEWNEIGH) {
 443                                 assert(bpf_map_update_elem(arp_table_map_fd,
 444                                                            &arp_entry.dst,
 445                                                            &arp_entry.mac, 0
 446                                                            ) == 0);
 447                         }
 448                 }
 449                 memset(&arp_entry, 0, sizeof(arp_entry));
 450                 memset(dsts, 0, sizeof(dsts));
 451         }
 452 }
 453
 454 /* Function to read the existing arp table  when the process is launched*/
 455 static int get_arp_table(int rtm_family)
 456 {
 457         struct sockaddr_nl sa;
 458         struct nlmsghdr *nh;
 459         int sock, seq = 0;
 460         struct msghdr msg;
 461         struct iovec iov;
 462         int ret = 0;
 463         int nll;
 464         struct {
 465                 struct nlmsghdr nl;
 466                 struct ndmsg rt;
 467                 char buf[8192];
 468         } req;
 469
 470         sock = socket(AF_NETLINK, SOCK_RAW, NETLINK_ROUTE);
 471         if (sock < 0) {
 472                 printf("open netlink socket: %s\n", strerror(errno));
 473                 return -1;
 474         }
 475         memset(&sa, 0, sizeof(sa));
 476         sa.nl_family = AF_NETLINK;
 477         if (bind(sock, (struct sockaddr *)&sa, sizeof(sa)) < 0) {
 478                 printf("bind to netlink: %s\n", strerror(errno));
 479                 ret = -1;
 480                 goto cleanup;
 481         }
 482         memset(&req, 0, sizeof(req));
 483         req.nl.nlmsg_len = NLMSG_LENGTH(sizeof(struct rtmsg));
 484         req.nl.nlmsg_flags = NLM_F_REQUEST | NLM_F_DUMP;
 485         req.nl.nlmsg_type = RTM_GETNEIGH;
 486         req.rt.ndm_state = NUD_REACHABLE;
 487         req.rt.ndm_family = rtm_family;
 488         req.nl.nlmsg_pid = 0;
 489         req.nl.nlmsg_seq = ++seq;
 490         memset(&msg, 0, sizeof(msg));
 491         iov.iov_base = (void *)&req.nl;
 492         iov.iov_len = req.nl.nlmsg_len;
 493         msg.msg_iov = &iov;
 494         msg.msg_iovlen = 1;
 495         ret = sendmsg(sock, &msg, 0);
 496         if (ret < 0) {
 497                 printf("send to netlink: %s\n", strerror(errno));
 498                 ret = -1;
 499                 goto cleanup;
 500         }
 501         memset(buf, 0, sizeof(buf));
 502         nll = recv_msg(sa, sock);
 503         if (nll < 0) {
 504                 printf("recv from netlink: %s\n", strerror(nll));
 505                 ret = -1;
 506                 goto cleanup;
 507         }
 508         nh = (struct nlmsghdr *)buf;
 509         read_arp(nh, nll);
 510 cleanup:
 511         close(sock);
 512         return ret;
 513 }
 514
 515 /* Function to keep track and update changes in route and arp table
 516  * Give regular statistics of packets forwarded
 517  */
 518 static int monitor_route(void)
 519 {
 520         unsigned int nr_cpus = bpf_num_possible_cpus();
 521         const unsigned int nr_keys = 256;
 522         struct pollfd fds_route, fds_arp;
 523         __u64 prev[nr_keys][nr_cpus];
 524         struct sockaddr_nl la, lr;
 525         __u64 values[nr_cpus];
 526         struct nlmsghdr *nh;
 527         int nll, ret = 0;
 528         int interval = 5;
 529         __u32 key;
 530         int i;
 531
 532         sock = socket(AF_NETLINK, SOCK_RAW, NETLINK_ROUTE);
 533         if (sock < 0) {
 534                 printf("open netlink socket: %s\n", strerror(errno));
 535                 return -1;
 536         }
 537
 538         fcntl(sock, F_SETFL, O_NONBLOCK);
 539         memset(&lr, 0, sizeof(lr));
 540         lr.nl_family = AF_NETLINK;
 541         lr.nl_groups = RTMGRP_IPV6_ROUTE | RTMGRP_IPV4_ROUTE | RTMGRP_NOTIFY;
 542         if (bind(sock, (struct sockaddr *)&lr, sizeof(lr)) < 0) {
 543                 printf("bind to netlink: %s\n", strerror(errno));
 544                 ret = -1;
 545                 goto cleanup;
 546         }
 547         fds_route.fd = sock;
 548         fds_route.events = POLL_IN;
 549
 550         sock_arp = socket(AF_NETLINK, SOCK_RAW, NETLINK_ROUTE);
 551         if (sock_arp < 0) {
 552                 printf("open netlink socket: %s\n", strerror(errno));
 553                 return -1;
 554         }
 555
 556         fcntl(sock_arp, F_SETFL, O_NONBLOCK);
 557         memset(&la, 0, sizeof(la));
 558         la.nl_family = AF_NETLINK;
 559         la.nl_groups = RTMGRP_NEIGH | RTMGRP_NOTIFY;
 560         if (bind(sock_arp, (struct sockaddr *)&la, sizeof(la)) < 0) {
 561                 printf("bind to netlink: %s\n", strerror(errno));
 562                 ret = -1;
 563                 goto cleanup;
 564         }
 565         fds_arp.fd = sock_arp;
 566         fds_arp.events = POLL_IN;
 567
 568         memset(prev, 0, sizeof(prev));
 569         do {
 570                 signal(SIGINT, close_and_exit);
 571                 signal(SIGTERM, close_and_exit);
 572
 573                 sleep(interval);
 574                 for (key = 0; key < nr_keys; key++) {
 575                         __u64 sum = 0;
 576
 577                         assert(bpf_map_lookup_elem(rxcnt_map_fd,
 578                                                    &key, values) == 0);
 579                         for (i = 0; i < nr_cpus; i++)
 580                                 sum += (values[i] - prev[key][i]);
 581                         if (sum)
 582                                 printf("proto %u: %10llu pkt/s\n",
 583                                        key, sum / interval);
 584                         memcpy(prev[key], values, sizeof(values));
 585                 }
 586
 587                 memset(buf, 0, sizeof(buf));
 588                 if (poll(&fds_route, 1, 3) == POLL_IN) {
 589                         nll = recv_msg(lr, sock);
 590                         if (nll < 0) {
 591                                 printf("recv from netlink: %s\n", strerror(nll));
 592                                 ret = -1;
 593                                 goto cleanup;
 594                         }
 595
 596                         nh = (struct nlmsghdr *)buf;
 597                         printf("Routing table updated.\n");
 598                         read_route(nh, nll);
 599                 }
 600                 memset(buf, 0, sizeof(buf));
 601                 if (poll(&fds_arp, 1, 3) == POLL_IN) {
 602                         nll = recv_msg(la, sock_arp);
 603                         if (nll < 0) {
 604                                 printf("recv from netlink: %s\n", strerror(nll));
 605                                 ret = -1;
 606                                 goto cleanup;
 607                         }
 608
 609                         nh = (struct nlmsghdr *)buf;
 610                         read_arp(nh, nll);
 611                 }
 612
 613         } while (1);
 614 cleanup:
 615         close(sock);
 616         return ret;
 617 }
 618
 619 static void usage(const char *prog)
 620 {
 621         fprintf(stderr,
 622                 "%s: %s [OPTS] interface name list\n\n"
 623                 "OPTS:\n"
 624                 "    -S    use skb-mode\n"
 625                 "    -F    force loading prog\n",
 626                 __func__, prog);
 627 }
 628
 629 int main(int ac, char **argv)
 630 {
 631         struct rlimit r = {RLIM_INFINITY, RLIM_INFINITY};
 632         struct bpf_prog_load_attr prog_load_attr = {
 633                 .prog_type      = BPF_PROG_TYPE_XDP,
 634         };
 635         struct bpf_prog_info info = {};
 636         __u32 info_len = sizeof(info);
 637         const char *optstr = "SF";
 638         struct bpf_object *obj;
 639         char filename[256];
 640         char **ifname_list;
 641         int prog_fd, opt;
 642         int err, i = 1;
 643
 644         snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
 645         prog_load_attr.file = filename;
 646
 647         total_ifindex = ac - 1;
 648         ifname_list = (argv + 1);
 649
 650         while ((opt = getopt(ac, argv, optstr)) != -1) {
 651                 switch (opt) {
 652                 case 'S':
 653                         flags |= XDP_FLAGS_SKB_MODE;
 654                         total_ifindex--;
 655                         ifname_list++;
 656                         break;
 657                 case 'F':
 658                         flags &= ~XDP_FLAGS_UPDATE_IF_NOEXIST;
 659                         total_ifindex--;
 660                         ifname_list++;
 661                         break;
 662                 default:
 663                         usage(basename(argv[0]));
 664                         return 1;
 665                 }
 666         }
 667
 668         if (optind == ac) {
 669                 usage(basename(argv[0]));
 670                 return 1;
 671         }
 672
 673         if (setrlimit(RLIMIT_MEMLOCK, &r)) {
 674                 perror("setrlimit(RLIMIT_MEMLOCK)");
 675                 return 1;
 676         }
 677
 678         if (bpf_prog_load_xattr(&prog_load_attr, &obj, &prog_fd))
 679                 return 1;
 680
 681         printf("\n**************loading bpf file*********************\n\n\n");
 682         if (!prog_fd) {
 683                 printf("bpf_prog_load_xattr: %s\n", strerror(errno));
 684                 return 1;
 685         }
 686
 687         lpm_map_fd = bpf_object__find_map_fd_by_name(obj, "lpm_map");
 688         rxcnt_map_fd = bpf_object__find_map_fd_by_name(obj, "rxcnt");
 689         arp_table_map_fd = bpf_object__find_map_fd_by_name(obj, "arp_table");
 690         exact_match_map_fd = bpf_object__find_map_fd_by_name(obj,
 691                                                              "exact_match");
 692         tx_port_map_fd = bpf_object__find_map_fd_by_name(obj, "tx_port");
 693         if (lpm_map_fd < 0 || rxcnt_map_fd < 0 || arp_table_map_fd < 0 ||
 694             exact_match_map_fd < 0 || tx_port_map_fd < 0) {
 695                 printf("bpf_object__find_map_fd_by_name failed\n");
 696                 return 1;
 697         }
 698
 699         ifindex_list = (int *)calloc(total_ifindex, sizeof(int *));
 700         for (i = 0; i < total_ifindex; i++) {
 701                 ifindex_list[i] = if_nametoindex(ifname_list[i]);
 702                 if (!ifindex_list[i]) {
 703                         printf("Couldn't translate interface name: %s",
 704                                strerror(errno));
 705                         return 1;
 706                 }
 707         }
 708         prog_id_list = (__u32 *)calloc(total_ifindex, sizeof(__u32 *));
 709         for (i = 0; i < total_ifindex; i++) {
 710                 if (bpf_set_link_xdp_fd(ifindex_list[i], prog_fd, flags) < 0) {
 711                         printf("link set xdp fd failed\n");
 712                         int recovery_index = i;
 713
 714                         for (i = 0; i < recovery_index; i++)
 715                                 bpf_set_link_xdp_fd(ifindex_list[i], -1, flags);
 716
 717                         return 1;
 718                 }
 719                 err = bpf_obj_get_info_by_fd(prog_fd, &info, &info_len);
 720                 if (err) {
 721                         printf("can't get prog info - %s\n", strerror(errno));
 722                         return err;
 723                 }
 724                 prog_id_list[i] = info.id;
 725                 memset(&info, 0, sizeof(info));
 726                 printf("Attached to %d\n", ifindex_list[i]);
 727         }
 728         signal(SIGINT, int_exit);
 729         signal(SIGTERM, int_exit);
 730
 731         printf("*******************ROUTE TABLE*************************\n\n\n");
 732         get_route_table(AF_INET);
 733         printf("*******************ARP TABLE***************************\n\n\n");
 734         get_arp_table(AF_INET);
 735         if (monitor_route() < 0) {
 736                 printf("Error in receiving route update");
 737                 return 1;
 738         }
 739
 740         return 0;
 741 }