linux/samples/bpf/xdp_router_ipv4_user.c
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   1// SPDX-License-Identifier: GPL-2.0-only
   2/* Copyright (C) 2017 Cavium, Inc.
   3 */
   4#include <linux/bpf.h>
   5#include <linux/netlink.h>
   6#include <linux/rtnetlink.h>
   7#include <assert.h>
   8#include <errno.h>
   9#include <signal.h>
  10#include <stdio.h>
  11#include <stdlib.h>
  12#include <string.h>
  13#include <sys/socket.h>
  14#include <unistd.h>
  15#include <bpf/bpf.h>
  16#include <arpa/inet.h>
  17#include <fcntl.h>
  18#include <poll.h>
  19#include <net/if.h>
  20#include <netdb.h>
  21#include <sys/ioctl.h>
  22#include <sys/syscall.h>
  23#include "bpf_util.h"
  24#include "libbpf.h"
  25#include <sys/resource.h>
  26#include <libgen.h>
  27
  28int sock, sock_arp, flags = XDP_FLAGS_UPDATE_IF_NOEXIST;
  29static int total_ifindex;
  30static int *ifindex_list;
  31static __u32 *prog_id_list;
  32char buf[8192];
  33static int lpm_map_fd;
  34static int rxcnt_map_fd;
  35static int arp_table_map_fd;
  36static int exact_match_map_fd;
  37static int tx_port_map_fd;
  38
  39static int get_route_table(int rtm_family);
  40static void int_exit(int sig)
  41{
  42        __u32 prog_id = 0;
  43        int i = 0;
  44
  45        for (i = 0; i < total_ifindex; i++) {
  46                if (bpf_get_link_xdp_id(ifindex_list[i], &prog_id, flags)) {
  47                        printf("bpf_get_link_xdp_id on iface %d failed\n",
  48                               ifindex_list[i]);
  49                        exit(1);
  50                }
  51                if (prog_id_list[i] == prog_id)
  52                        bpf_set_link_xdp_fd(ifindex_list[i], -1, flags);
  53                else if (!prog_id)
  54                        printf("couldn't find a prog id on iface %d\n",
  55                               ifindex_list[i]);
  56                else
  57                        printf("program on iface %d changed, not removing\n",
  58                               ifindex_list[i]);
  59                prog_id = 0;
  60        }
  61        exit(0);
  62}
  63
  64static void close_and_exit(int sig)
  65{
  66        close(sock);
  67        close(sock_arp);
  68
  69        int_exit(0);
  70}
  71
  72/* Get the mac address of the interface given interface name */
  73static __be64 getmac(char *iface)
  74{
  75        struct ifreq ifr;
  76        __be64 mac = 0;
  77        int fd, i;
  78
  79        fd = socket(AF_INET, SOCK_DGRAM, 0);
  80        ifr.ifr_addr.sa_family = AF_INET;
  81        strncpy(ifr.ifr_name, iface, IFNAMSIZ - 1);
  82        if (ioctl(fd, SIOCGIFHWADDR, &ifr) < 0) {
  83                printf("ioctl failed leaving....\n");
  84                return -1;
  85        }
  86        for (i = 0; i < 6 ; i++)
  87                *((__u8 *)&mac + i) = (__u8)ifr.ifr_hwaddr.sa_data[i];
  88        close(fd);
  89        return mac;
  90}
  91
  92static int recv_msg(struct sockaddr_nl sock_addr, int sock)
  93{
  94        struct nlmsghdr *nh;
  95        int len, nll = 0;
  96        char *buf_ptr;
  97
  98        buf_ptr = buf;
  99        while (1) {
 100                len = recv(sock, buf_ptr, sizeof(buf) - nll, 0);
 101                if (len < 0)
 102                        return len;
 103
 104                nh = (struct nlmsghdr *)buf_ptr;
 105
 106                if (nh->nlmsg_type == NLMSG_DONE)
 107                        break;
 108                buf_ptr += len;
 109                nll += len;
 110                if ((sock_addr.nl_groups & RTMGRP_NEIGH) == RTMGRP_NEIGH)
 111                        break;
 112
 113                if ((sock_addr.nl_groups & RTMGRP_IPV4_ROUTE) == RTMGRP_IPV4_ROUTE)
 114                        break;
 115        }
 116        return nll;
 117}
 118
 119/* Function to parse the route entry returned by netlink
 120 * Updates the route entry related map entries
 121 */
 122static void read_route(struct nlmsghdr *nh, int nll)
 123{
 124        char dsts[24], gws[24], ifs[16], dsts_len[24], metrics[24];
 125        struct bpf_lpm_trie_key *prefix_key;
 126        struct rtattr *rt_attr;
 127        struct rtmsg *rt_msg;
 128        int rtm_family;
 129        int rtl;
 130        int i;
 131        struct route_table {
 132                int  dst_len, iface, metric;
 133                char *iface_name;
 134                __be32 dst, gw;
 135                __be64 mac;
 136        } route;
 137        struct arp_table {
 138                __be64 mac;
 139                __be32 dst;
 140        };
 141
 142        struct direct_map {
 143                struct arp_table arp;
 144                int ifindex;
 145                __be64 mac;
 146        } direct_entry;
 147
 148        if (nh->nlmsg_type == RTM_DELROUTE)
 149                printf("DELETING Route entry\n");
 150        else if (nh->nlmsg_type == RTM_GETROUTE)
 151                printf("READING Route entry\n");
 152        else if (nh->nlmsg_type == RTM_NEWROUTE)
 153                printf("NEW Route entry\n");
 154        else
 155                printf("%d\n", nh->nlmsg_type);
 156
 157        memset(&route, 0, sizeof(route));
 158        printf("Destination\t\tGateway\t\tGenmask\t\tMetric\t\tIface\n");
 159        for (; NLMSG_OK(nh, nll); nh = NLMSG_NEXT(nh, nll)) {
 160                rt_msg = (struct rtmsg *)NLMSG_DATA(nh);
 161                rtm_family = rt_msg->rtm_family;
 162                if (rtm_family == AF_INET)
 163                        if (rt_msg->rtm_table != RT_TABLE_MAIN)
 164                                continue;
 165                rt_attr = (struct rtattr *)RTM_RTA(rt_msg);
 166                rtl = RTM_PAYLOAD(nh);
 167
 168                for (; RTA_OK(rt_attr, rtl); rt_attr = RTA_NEXT(rt_attr, rtl)) {
 169                        switch (rt_attr->rta_type) {
 170                        case NDA_DST:
 171                                sprintf(dsts, "%u",
 172                                        (*((__be32 *)RTA_DATA(rt_attr))));
 173                                break;
 174                        case RTA_GATEWAY:
 175                                sprintf(gws, "%u",
 176                                        *((__be32 *)RTA_DATA(rt_attr)));
 177                                break;
 178                        case RTA_OIF:
 179                                sprintf(ifs, "%u",
 180                                        *((int *)RTA_DATA(rt_attr)));
 181                                break;
 182                        case RTA_METRICS:
 183                                sprintf(metrics, "%u",
 184                                        *((int *)RTA_DATA(rt_attr)));
 185                        default:
 186                                break;
 187                        }
 188                }
 189                sprintf(dsts_len, "%d", rt_msg->rtm_dst_len);
 190                route.dst = atoi(dsts);
 191                route.dst_len = atoi(dsts_len);
 192                route.gw = atoi(gws);
 193                route.iface = atoi(ifs);
 194                route.metric = atoi(metrics);
 195                route.iface_name = alloca(sizeof(char *) * IFNAMSIZ);
 196                route.iface_name = if_indextoname(route.iface, route.iface_name);
 197                route.mac = getmac(route.iface_name);
 198                if (route.mac == -1)
 199                        int_exit(0);
 200                assert(bpf_map_update_elem(tx_port_map_fd,
 201                                           &route.iface, &route.iface, 0) == 0);
 202                if (rtm_family == AF_INET) {
 203                        struct trie_value {
 204                                __u8 prefix[4];
 205                                __be64 value;
 206                                int ifindex;
 207                                int metric;
 208                                __be32 gw;
 209                        } *prefix_value;
 210
 211                        prefix_key = alloca(sizeof(*prefix_key) + 3);
 212                        prefix_value = alloca(sizeof(*prefix_value));
 213
 214                        prefix_key->prefixlen = 32;
 215                        prefix_key->prefixlen = route.dst_len;
 216                        direct_entry.mac = route.mac & 0xffffffffffff;
 217                        direct_entry.ifindex = route.iface;
 218                        direct_entry.arp.mac = 0;
 219                        direct_entry.arp.dst = 0;
 220                        if (route.dst_len == 32) {
 221                                if (nh->nlmsg_type == RTM_DELROUTE) {
 222                                        assert(bpf_map_delete_elem(exact_match_map_fd,
 223                                                                   &route.dst) == 0);
 224                                } else {
 225                                        if (bpf_map_lookup_elem(arp_table_map_fd,
 226                                                                &route.dst,
 227                                                                &direct_entry.arp.mac) == 0)
 228                                                direct_entry.arp.dst = route.dst;
 229                                        assert(bpf_map_update_elem(exact_match_map_fd,
 230                                                                   &route.dst,
 231                                                                   &direct_entry, 0) == 0);
 232                                }
 233                        }
 234                        for (i = 0; i < 4; i++)
 235                                prefix_key->data[i] = (route.dst >> i * 8) & 0xff;
 236
 237                        printf("%3d.%d.%d.%d\t\t%3x\t\t%d\t\t%d\t\t%s\n",
 238                               (int)prefix_key->data[0],
 239                               (int)prefix_key->data[1],
 240                               (int)prefix_key->data[2],
 241                               (int)prefix_key->data[3],
 242                               route.gw, route.dst_len,
 243                               route.metric,
 244                               route.iface_name);
 245                        if (bpf_map_lookup_elem(lpm_map_fd, prefix_key,
 246                                                prefix_value) < 0) {
 247                                for (i = 0; i < 4; i++)
 248                                        prefix_value->prefix[i] = prefix_key->data[i];
 249                                prefix_value->value = route.mac & 0xffffffffffff;
 250                                prefix_value->ifindex = route.iface;
 251                                prefix_value->gw = route.gw;
 252                                prefix_value->metric = route.metric;
 253
 254                                assert(bpf_map_update_elem(lpm_map_fd,
 255                                                           prefix_key,
 256                                                           prefix_value, 0
 257                                                           ) == 0);
 258                        } else {
 259                                if (nh->nlmsg_type == RTM_DELROUTE) {
 260                                        printf("deleting entry\n");
 261                                        printf("prefix key=%d.%d.%d.%d/%d",
 262                                               prefix_key->data[0],
 263                                               prefix_key->data[1],
 264                                               prefix_key->data[2],
 265                                               prefix_key->data[3],
 266                                               prefix_key->prefixlen);
 267                                        assert(bpf_map_delete_elem(lpm_map_fd,
 268                                                                   prefix_key
 269                                                                   ) == 0);
 270                                        /* Rereading the route table to check if
 271                                         * there is an entry with the same
 272                                         * prefix but a different metric as the
 273                                         * deleted enty.
 274                                         */
 275                                        get_route_table(AF_INET);
 276                                } else if (prefix_key->data[0] ==
 277                                           prefix_value->prefix[0] &&
 278                                           prefix_key->data[1] ==
 279                                           prefix_value->prefix[1] &&
 280                                           prefix_key->data[2] ==
 281                                           prefix_value->prefix[2] &&
 282                                           prefix_key->data[3] ==
 283                                           prefix_value->prefix[3] &&
 284                                           route.metric >= prefix_value->metric) {
 285                                        continue;
 286                                } else {
 287                                        for (i = 0; i < 4; i++)
 288                                                prefix_value->prefix[i] =
 289                                                        prefix_key->data[i];
 290                                        prefix_value->value =
 291                                                route.mac & 0xffffffffffff;
 292                                        prefix_value->ifindex = route.iface;
 293                                        prefix_value->gw = route.gw;
 294                                        prefix_value->metric = route.metric;
 295                                        assert(bpf_map_update_elem(lpm_map_fd,
 296                                                                   prefix_key,
 297                                                                   prefix_value,
 298                                                                   0) == 0);
 299                                }
 300                        }
 301                }
 302                memset(&route, 0, sizeof(route));
 303                memset(dsts, 0, sizeof(dsts));
 304                memset(dsts_len, 0, sizeof(dsts_len));
 305                memset(gws, 0, sizeof(gws));
 306                memset(ifs, 0, sizeof(ifs));
 307                memset(&route, 0, sizeof(route));
 308        }
 309}
 310
 311/* Function to read the existing route table  when the process is launched*/
 312static int get_route_table(int rtm_family)
 313{
 314        struct sockaddr_nl sa;
 315        struct nlmsghdr *nh;
 316        int sock, seq = 0;
 317        struct msghdr msg;
 318        struct iovec iov;
 319        int ret = 0;
 320        int nll;
 321
 322        struct {
 323                struct nlmsghdr nl;
 324                struct rtmsg rt;
 325                char buf[8192];
 326        } req;
 327
 328        sock = socket(AF_NETLINK, SOCK_RAW, NETLINK_ROUTE);
 329        if (sock < 0) {
 330                printf("open netlink socket: %s\n", strerror(errno));
 331                return -1;
 332        }
 333        memset(&sa, 0, sizeof(sa));
 334        sa.nl_family = AF_NETLINK;
 335        if (bind(sock, (struct sockaddr *)&sa, sizeof(sa)) < 0) {
 336                printf("bind to netlink: %s\n", strerror(errno));
 337                ret = -1;
 338                goto cleanup;
 339        }
 340        memset(&req, 0, sizeof(req));
 341        req.nl.nlmsg_len = NLMSG_LENGTH(sizeof(struct rtmsg));
 342        req.nl.nlmsg_flags = NLM_F_REQUEST | NLM_F_DUMP;
 343        req.nl.nlmsg_type = RTM_GETROUTE;
 344
 345        req.rt.rtm_family = rtm_family;
 346        req.rt.rtm_table = RT_TABLE_MAIN;
 347        req.nl.nlmsg_pid = 0;
 348        req.nl.nlmsg_seq = ++seq;
 349        memset(&msg, 0, sizeof(msg));
 350        iov.iov_base = (void *)&req.nl;
 351        iov.iov_len = req.nl.nlmsg_len;
 352        msg.msg_iov = &iov;
 353        msg.msg_iovlen = 1;
 354        ret = sendmsg(sock, &msg, 0);
 355        if (ret < 0) {
 356                printf("send to netlink: %s\n", strerror(errno));
 357                ret = -1;
 358                goto cleanup;
 359        }
 360        memset(buf, 0, sizeof(buf));
 361        nll = recv_msg(sa, sock);
 362        if (nll < 0) {
 363                printf("recv from netlink: %s\n", strerror(nll));
 364                ret = -1;
 365                goto cleanup;
 366        }
 367        nh = (struct nlmsghdr *)buf;
 368        read_route(nh, nll);
 369cleanup:
 370        close(sock);
 371        return ret;
 372}
 373
 374/* Function to parse the arp entry returned by netlink
 375 * Updates the arp entry related map entries
 376 */
 377static void read_arp(struct nlmsghdr *nh, int nll)
 378{
 379        struct rtattr *rt_attr;
 380        char dsts[24], mac[24];
 381        struct ndmsg *rt_msg;
 382        int rtl, ndm_family;
 383
 384        struct arp_table {
 385                __be64 mac;
 386                __be32 dst;
 387        } arp_entry;
 388        struct direct_map {
 389                struct arp_table arp;
 390                int ifindex;
 391                __be64 mac;
 392        } direct_entry;
 393
 394        if (nh->nlmsg_type == RTM_GETNEIGH)
 395                printf("READING arp entry\n");
 396        printf("Address\tHwAddress\n");
 397        for (; NLMSG_OK(nh, nll); nh = NLMSG_NEXT(nh, nll)) {
 398                rt_msg = (struct ndmsg *)NLMSG_DATA(nh);
 399                rt_attr = (struct rtattr *)RTM_RTA(rt_msg);
 400                ndm_family = rt_msg->ndm_family;
 401                rtl = RTM_PAYLOAD(nh);
 402                for (; RTA_OK(rt_attr, rtl); rt_attr = RTA_NEXT(rt_attr, rtl)) {
 403                        switch (rt_attr->rta_type) {
 404                        case NDA_DST:
 405                                sprintf(dsts, "%u",
 406                                        *((__be32 *)RTA_DATA(rt_attr)));
 407                                break;
 408                        case NDA_LLADDR:
 409                                sprintf(mac, "%lld",
 410                                        *((__be64 *)RTA_DATA(rt_attr)));
 411                                break;
 412                        default:
 413                                break;
 414                        }
 415                }
 416                arp_entry.dst = atoi(dsts);
 417                arp_entry.mac = atol(mac);
 418                printf("%x\t\t%llx\n", arp_entry.dst, arp_entry.mac);
 419                if (ndm_family == AF_INET) {
 420                        if (bpf_map_lookup_elem(exact_match_map_fd,
 421                                                &arp_entry.dst,
 422                                                &direct_entry) == 0) {
 423                                if (nh->nlmsg_type == RTM_DELNEIGH) {
 424                                        direct_entry.arp.dst = 0;
 425                                        direct_entry.arp.mac = 0;
 426                                } else if (nh->nlmsg_type == RTM_NEWNEIGH) {
 427                                        direct_entry.arp.dst = arp_entry.dst;
 428                                        direct_entry.arp.mac = arp_entry.mac;
 429                                }
 430                                assert(bpf_map_update_elem(exact_match_map_fd,
 431                                                           &arp_entry.dst,
 432                                                           &direct_entry, 0
 433                                                           ) == 0);
 434                                memset(&direct_entry, 0, sizeof(direct_entry));
 435                        }
 436                        if (nh->nlmsg_type == RTM_DELNEIGH) {
 437                                assert(bpf_map_delete_elem(arp_table_map_fd,
 438                                                           &arp_entry.dst) == 0);
 439                        } else if (nh->nlmsg_type == RTM_NEWNEIGH) {
 440                                assert(bpf_map_update_elem(arp_table_map_fd,
 441                                                           &arp_entry.dst,
 442                                                           &arp_entry.mac, 0
 443                                                           ) == 0);
 444                        }
 445                }
 446                memset(&arp_entry, 0, sizeof(arp_entry));
 447                memset(dsts, 0, sizeof(dsts));
 448        }
 449}
 450
 451/* Function to read the existing arp table  when the process is launched*/
 452static int get_arp_table(int rtm_family)
 453{
 454        struct sockaddr_nl sa;
 455        struct nlmsghdr *nh;
 456        int sock, seq = 0;
 457        struct msghdr msg;
 458        struct iovec iov;
 459        int ret = 0;
 460        int nll;
 461        struct {
 462                struct nlmsghdr nl;
 463                struct ndmsg rt;
 464                char buf[8192];
 465        } req;
 466
 467        sock = socket(AF_NETLINK, SOCK_RAW, NETLINK_ROUTE);
 468        if (sock < 0) {
 469                printf("open netlink socket: %s\n", strerror(errno));
 470                return -1;
 471        }
 472        memset(&sa, 0, sizeof(sa));
 473        sa.nl_family = AF_NETLINK;
 474        if (bind(sock, (struct sockaddr *)&sa, sizeof(sa)) < 0) {
 475                printf("bind to netlink: %s\n", strerror(errno));
 476                ret = -1;
 477                goto cleanup;
 478        }
 479        memset(&req, 0, sizeof(req));
 480        req.nl.nlmsg_len = NLMSG_LENGTH(sizeof(struct rtmsg));
 481        req.nl.nlmsg_flags = NLM_F_REQUEST | NLM_F_DUMP;
 482        req.nl.nlmsg_type = RTM_GETNEIGH;
 483        req.rt.ndm_state = NUD_REACHABLE;
 484        req.rt.ndm_family = rtm_family;
 485        req.nl.nlmsg_pid = 0;
 486        req.nl.nlmsg_seq = ++seq;
 487        memset(&msg, 0, sizeof(msg));
 488        iov.iov_base = (void *)&req.nl;
 489        iov.iov_len = req.nl.nlmsg_len;
 490        msg.msg_iov = &iov;
 491        msg.msg_iovlen = 1;
 492        ret = sendmsg(sock, &msg, 0);
 493        if (ret < 0) {
 494                printf("send to netlink: %s\n", strerror(errno));
 495                ret = -1;
 496                goto cleanup;
 497        }
 498        memset(buf, 0, sizeof(buf));
 499        nll = recv_msg(sa, sock);
 500        if (nll < 0) {
 501                printf("recv from netlink: %s\n", strerror(nll));
 502                ret = -1;
 503                goto cleanup;
 504        }
 505        nh = (struct nlmsghdr *)buf;
 506        read_arp(nh, nll);
 507cleanup:
 508        close(sock);
 509        return ret;
 510}
 511
 512/* Function to keep track and update changes in route and arp table
 513 * Give regular statistics of packets forwarded
 514 */
 515static int monitor_route(void)
 516{
 517        unsigned int nr_cpus = bpf_num_possible_cpus();
 518        const unsigned int nr_keys = 256;
 519        struct pollfd fds_route, fds_arp;
 520        __u64 prev[nr_keys][nr_cpus];
 521        struct sockaddr_nl la, lr;
 522        __u64 values[nr_cpus];
 523        struct nlmsghdr *nh;
 524        int nll, ret = 0;
 525        int interval = 5;
 526        __u32 key;
 527        int i;
 528
 529        sock = socket(AF_NETLINK, SOCK_RAW, NETLINK_ROUTE);
 530        if (sock < 0) {
 531                printf("open netlink socket: %s\n", strerror(errno));
 532                return -1;
 533        }
 534
 535        fcntl(sock, F_SETFL, O_NONBLOCK);
 536        memset(&lr, 0, sizeof(lr));
 537        lr.nl_family = AF_NETLINK;
 538        lr.nl_groups = RTMGRP_IPV6_ROUTE | RTMGRP_IPV4_ROUTE | RTMGRP_NOTIFY;
 539        if (bind(sock, (struct sockaddr *)&lr, sizeof(lr)) < 0) {
 540                printf("bind to netlink: %s\n", strerror(errno));
 541                ret = -1;
 542                goto cleanup;
 543        }
 544        fds_route.fd = sock;
 545        fds_route.events = POLL_IN;
 546
 547        sock_arp = socket(AF_NETLINK, SOCK_RAW, NETLINK_ROUTE);
 548        if (sock_arp < 0) {
 549                printf("open netlink socket: %s\n", strerror(errno));
 550                return -1;
 551        }
 552
 553        fcntl(sock_arp, F_SETFL, O_NONBLOCK);
 554        memset(&la, 0, sizeof(la));
 555        la.nl_family = AF_NETLINK;
 556        la.nl_groups = RTMGRP_NEIGH | RTMGRP_NOTIFY;
 557        if (bind(sock_arp, (struct sockaddr *)&la, sizeof(la)) < 0) {
 558                printf("bind to netlink: %s\n", strerror(errno));
 559                ret = -1;
 560                goto cleanup;
 561        }
 562        fds_arp.fd = sock_arp;
 563        fds_arp.events = POLL_IN;
 564
 565        memset(prev, 0, sizeof(prev));
 566        do {
 567                signal(SIGINT, close_and_exit);
 568                signal(SIGTERM, close_and_exit);
 569
 570                sleep(interval);
 571                for (key = 0; key < nr_keys; key++) {
 572                        __u64 sum = 0;
 573
 574                        assert(bpf_map_lookup_elem(rxcnt_map_fd,
 575                                                   &key, values) == 0);
 576                        for (i = 0; i < nr_cpus; i++)
 577                                sum += (values[i] - prev[key][i]);
 578                        if (sum)
 579                                printf("proto %u: %10llu pkt/s\n",
 580                                       key, sum / interval);
 581                        memcpy(prev[key], values, sizeof(values));
 582                }
 583
 584                memset(buf, 0, sizeof(buf));
 585                if (poll(&fds_route, 1, 3) == POLL_IN) {
 586                        nll = recv_msg(lr, sock);
 587                        if (nll < 0) {
 588                                printf("recv from netlink: %s\n", strerror(nll));
 589                                ret = -1;
 590                                goto cleanup;
 591                        }
 592
 593                        nh = (struct nlmsghdr *)buf;
 594                        printf("Routing table updated.\n");
 595                        read_route(nh, nll);
 596                }
 597                memset(buf, 0, sizeof(buf));
 598                if (poll(&fds_arp, 1, 3) == POLL_IN) {
 599                        nll = recv_msg(la, sock_arp);
 600                        if (nll < 0) {
 601                                printf("recv from netlink: %s\n", strerror(nll));
 602                                ret = -1;
 603                                goto cleanup;
 604                        }
 605
 606                        nh = (struct nlmsghdr *)buf;
 607                        read_arp(nh, nll);
 608                }
 609
 610        } while (1);
 611cleanup:
 612        close(sock);
 613        return ret;
 614}
 615
 616static void usage(const char *prog)
 617{
 618        fprintf(stderr,
 619                "%s: %s [OPTS] interface name list\n\n"
 620                "OPTS:\n"
 621                "    -S    use skb-mode\n"
 622                "    -F    force loading prog\n",
 623                __func__, prog);
 624}
 625
 626int main(int ac, char **argv)
 627{
 628        struct rlimit r = {RLIM_INFINITY, RLIM_INFINITY};
 629        struct bpf_prog_load_attr prog_load_attr = {
 630                .prog_type      = BPF_PROG_TYPE_XDP,
 631        };
 632        struct bpf_prog_info info = {};
 633        __u32 info_len = sizeof(info);
 634        const char *optstr = "SF";
 635        struct bpf_object *obj;
 636        char filename[256];
 637        char **ifname_list;
 638        int prog_fd, opt;
 639        int err, i = 1;
 640
 641        snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
 642        prog_load_attr.file = filename;
 643
 644        total_ifindex = ac - 1;
 645        ifname_list = (argv + 1);
 646
 647        while ((opt = getopt(ac, argv, optstr)) != -1) {
 648                switch (opt) {
 649                case 'S':
 650                        flags |= XDP_FLAGS_SKB_MODE;
 651                        total_ifindex--;
 652                        ifname_list++;
 653                        break;
 654                case 'F':
 655                        flags &= ~XDP_FLAGS_UPDATE_IF_NOEXIST;
 656                        total_ifindex--;
 657                        ifname_list++;
 658                        break;
 659                default:
 660                        usage(basename(argv[0]));
 661                        return 1;
 662                }
 663        }
 664
 665        if (optind == ac) {
 666                usage(basename(argv[0]));
 667                return 1;
 668        }
 669
 670        if (setrlimit(RLIMIT_MEMLOCK, &r)) {
 671                perror("setrlimit(RLIMIT_MEMLOCK)");
 672                return 1;
 673        }
 674
 675        if (bpf_prog_load_xattr(&prog_load_attr, &obj, &prog_fd))
 676                return 1;
 677
 678        printf("\n**************loading bpf file*********************\n\n\n");
 679        if (!prog_fd) {
 680                printf("bpf_prog_load_xattr: %s\n", strerror(errno));
 681                return 1;
 682        }
 683
 684        lpm_map_fd = bpf_object__find_map_fd_by_name(obj, "lpm_map");
 685        rxcnt_map_fd = bpf_object__find_map_fd_by_name(obj, "rxcnt");
 686        arp_table_map_fd = bpf_object__find_map_fd_by_name(obj, "arp_table");
 687        exact_match_map_fd = bpf_object__find_map_fd_by_name(obj,
 688                                                             "exact_match");
 689        tx_port_map_fd = bpf_object__find_map_fd_by_name(obj, "tx_port");
 690        if (lpm_map_fd < 0 || rxcnt_map_fd < 0 || arp_table_map_fd < 0 ||
 691            exact_match_map_fd < 0 || tx_port_map_fd < 0) {
 692                printf("bpf_object__find_map_fd_by_name failed\n");
 693                return 1;
 694        }
 695
 696        ifindex_list = (int *)calloc(total_ifindex, sizeof(int *));
 697        for (i = 0; i < total_ifindex; i++) {
 698                ifindex_list[i] = if_nametoindex(ifname_list[i]);
 699                if (!ifindex_list[i]) {
 700                        printf("Couldn't translate interface name: %s",
 701                               strerror(errno));
 702                        return 1;
 703                }
 704        }
 705        prog_id_list = (__u32 *)calloc(total_ifindex, sizeof(__u32 *));
 706        for (i = 0; i < total_ifindex; i++) {
 707                if (bpf_set_link_xdp_fd(ifindex_list[i], prog_fd, flags) < 0) {
 708                        printf("link set xdp fd failed\n");
 709                        int recovery_index = i;
 710
 711                        for (i = 0; i < recovery_index; i++)
 712                                bpf_set_link_xdp_fd(ifindex_list[i], -1, flags);
 713
 714                        return 1;
 715                }
 716                err = bpf_obj_get_info_by_fd(prog_fd, &info, &info_len);
 717                if (err) {
 718                        printf("can't get prog info - %s\n", strerror(errno));
 719                        return err;
 720                }
 721                prog_id_list[i] = info.id;
 722                memset(&info, 0, sizeof(info));
 723                printf("Attached to %d\n", ifindex_list[i]);
 724        }
 725        signal(SIGINT, int_exit);
 726        signal(SIGTERM, int_exit);
 727
 728        printf("*******************ROUTE TABLE*************************\n\n\n");
 729        get_route_table(AF_INET);
 730        printf("*******************ARP TABLE***************************\n\n\n");
 731        get_arp_table(AF_INET);
 732        if (monitor_route() < 0) {
 733                printf("Error in receiving route update");
 734                return 1;
 735        }
 736
 737        return 0;
 738}
 739