app/test-pmd/icmpecho.c

   1 /*-
   2  *   BSD LICENSE
   3  *
   4  *   Copyright(c) 2013 6WIND
   5  *   All rights reserved.
   6  *
   7  *   Redistribution and use in source and binary forms, with or without
   8  *   modification, are permitted provided that the following conditions
   9  *   are met:
  10  *
  11  *     * Redistributions of source code must retain the above copyright
  12  *       notice, this list of conditions and the following disclaimer.
  13  *     * Redistributions in binary form must reproduce the above copyright
  14  *       notice, this list of conditions and the following disclaimer in
  15  *       the documentation and/or other materials provided with the
  16  *       distribution.
  17  *     * Neither the name of 6WIND S.A. nor the names of its
  18  *       contributors may be used to endorse or promote products derived
  19  *       from this software without specific prior written permission.
  20  *
  21  *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  22  *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  23  *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  24  *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  25  *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  26  *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  27  *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  28  *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  29  *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  30  *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  31  *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  32  *
  33  */
  34
  35 #include <stdarg.h>
  36 #include <string.h>
  37 #include <stdio.h>
  38 #include <errno.h>
  39 #include <stdint.h>
  40 #include <unistd.h>
  41 #include <inttypes.h>
  42
  43 #include <sys/queue.h>
  44 #include <sys/stat.h>
  45
  46 #include <rte_common.h>
  47 #include <rte_byteorder.h>
  48 #include <rte_log.h>
  49 #include <rte_debug.h>
  50 #include <rte_cycles.h>
  51 #include <rte_per_lcore.h>
  52 #include <rte_lcore.h>
  53 #include <rte_atomic.h>
  54 #include <rte_branch_prediction.h>
  55 #include <rte_ring.h>
  56 #include <rte_memory.h>
  57 #include <rte_mempool.h>
  58 #include <rte_mbuf.h>
  59 #include <rte_ether.h>
  60 #include <rte_ethdev.h>
  61 #include <rte_arp.h>
  62 #include <rte_ip.h>
  63 #include <rte_icmp.h>
  64 #include <rte_string_fns.h>
  65
  66 #include "testpmd.h"
  67
  68 static const char *
  69 arp_op_name(uint16_t arp_op)
  70 {
  71         switch (arp_op ) {
  72         case ARP_OP_REQUEST:
  73                 return "ARP Request";
  74         case ARP_OP_REPLY:
  75                 return "ARP Reply";
  76         case ARP_OP_REVREQUEST:
  77                 return "Reverse ARP Request";
  78         case ARP_OP_REVREPLY:
  79                 return "Reverse ARP Reply";
  80         case ARP_OP_INVREQUEST:
  81                 return "Peer Identify Request";
  82         case ARP_OP_INVREPLY:
  83                 return "Peer Identify Reply";
  84         default:
  85                 break;
  86         }
  87         return "Unkwown ARP op";
  88 }
  89
  90 static const char *
  91 ip_proto_name(uint16_t ip_proto)
  92 {
  93         static const char * ip_proto_names[] = {
  94                 "IP6HOPOPTS", /**< IP6 hop-by-hop options */
  95                 "ICMP",       /**< control message protocol */
  96                 "IGMP",       /**< group mgmt protocol */
  97                 "GGP",        /**< gateway^2 (deprecated) */
  98                 "IPv4",       /**< IPv4 encapsulation */
  99
 100                 "UNASSIGNED",
 101                 "TCP",        /**< transport control protocol */
 102                 "ST",         /**< Stream protocol II */
 103                 "EGP",        /**< exterior gateway protocol */
 104                 "PIGP",       /**< private interior gateway */
 105
 106                 "RCC_MON",    /**< BBN RCC Monitoring */
 107                 "NVPII",      /**< network voice protocol*/
 108                 "PUP",        /**< pup */
 109                 "ARGUS",      /**< Argus */
 110                 "EMCON",      /**< EMCON */
 111
 112                 "XNET",       /**< Cross Net Debugger */
 113                 "CHAOS",      /**< Chaos*/
 114                 "UDP",        /**< user datagram protocol */
 115                 "MUX",        /**< Multiplexing */
 116                 "DCN_MEAS",   /**< DCN Measurement Subsystems */
 117
 118                 "HMP",        /**< Host Monitoring */
 119                 "PRM",        /**< Packet Radio Measurement */
 120                 "XNS_IDP",    /**< xns idp */
 121                 "TRUNK1",     /**< Trunk-1 */
 122                 "TRUNK2",     /**< Trunk-2 */
 123
 124                 "LEAF1",      /**< Leaf-1 */
 125                 "LEAF2",      /**< Leaf-2 */
 126                 "RDP",        /**< Reliable Data */
 127                 "IRTP",       /**< Reliable Transaction */
 128                 "TP4",        /**< tp-4 w/ class negotiation */
 129
 130                 "BLT",        /**< Bulk Data Transfer */
 131                 "NSP",        /**< Network Services */
 132                 "INP",        /**< Merit Internodal */
 133                 "SEP",        /**< Sequential Exchange */
 134                 "3PC",        /**< Third Party Connect */
 135
 136                 "IDPR",       /**< InterDomain Policy Routing */
 137                 "XTP",        /**< XTP */
 138                 "DDP",        /**< Datagram Delivery */
 139                 "CMTP",       /**< Control Message Transport */
 140                 "TPXX",       /**< TP++ Transport */
 141
 142                 "ILTP",       /**< IL transport protocol */
 143                 "IPv6_HDR",   /**< IP6 header */
 144                 "SDRP",       /**< Source Demand Routing */
 145                 "IPv6_RTG",   /**< IP6 routing header */
 146                 "IPv6_FRAG",  /**< IP6 fragmentation header */
 147
 148                 "IDRP",       /**< InterDomain Routing*/
 149                 "RSVP",       /**< resource reservation */
 150                 "GRE",        /**< General Routing Encap. */
 151                 "MHRP",       /**< Mobile Host Routing */
 152                 "BHA",        /**< BHA */
 153
 154                 "ESP",        /**< IP6 Encap Sec. Payload */
 155                 "AH",         /**< IP6 Auth Header */
 156                 "INLSP",      /**< Integ. Net Layer Security */
 157                 "SWIPE",      /**< IP with encryption */
 158                 "NHRP",       /**< Next Hop Resolution */
 159
 160                 "UNASSIGNED",
 161                 "UNASSIGNED",
 162                 "UNASSIGNED",
 163                 "ICMPv6",     /**< ICMP6 */
 164                 "IPv6NONEXT", /**< IP6 no next header */
 165
 166                 "Ipv6DSTOPTS",/**< IP6 destination option */
 167                 "AHIP",       /**< any host internal protocol */
 168                 "CFTP",       /**< CFTP */
 169                 "HELLO",      /**< "hello" routing protocol */
 170                 "SATEXPAK",   /**< SATNET/Backroom EXPAK */
 171
 172                 "KRYPTOLAN",  /**< Kryptolan */
 173                 "RVD",        /**< Remote Virtual Disk */
 174                 "IPPC",       /**< Pluribus Packet Core */
 175                 "ADFS",       /**< Any distributed FS */
 176                 "SATMON",     /**< Satnet Monitoring */
 177
 178                 "VISA",       /**< VISA Protocol */
 179                 "IPCV",       /**< Packet Core Utility */
 180                 "CPNX",       /**< Comp. Prot. Net. Executive */
 181                 "CPHB",       /**< Comp. Prot. HeartBeat */
 182                 "WSN",        /**< Wang Span Network */
 183
 184                 "PVP",        /**< Packet Video Protocol */
 185                 "BRSATMON",   /**< BackRoom SATNET Monitoring */
 186                 "ND",         /**< Sun net disk proto (temp.) */
 187                 "WBMON",      /**< WIDEBAND Monitoring */
 188                 "WBEXPAK",    /**< WIDEBAND EXPAK */
 189
 190                 "EON",        /**< ISO cnlp */
 191                 "VMTP",       /**< VMTP */
 192                 "SVMTP",      /**< Secure VMTP */
 193                 "VINES",      /**< Banyon VINES */
 194                 "TTP",        /**< TTP */
 195
 196                 "IGP",        /**< NSFNET-IGP */
 197                 "DGP",        /**< dissimilar gateway prot. */
 198                 "TCF",        /**< TCF */
 199                 "IGRP",       /**< Cisco/GXS IGRP */
 200                 "OSPFIGP",    /**< OSPFIGP */
 201
 202                 "SRPC",       /**< Strite RPC protocol */
 203                 "LARP",       /**< Locus Address Resoloution */
 204                 "MTP",        /**< Multicast Transport */
 205                 "AX25",       /**< AX.25 Frames */
 206                 "4IN4",       /**< IP encapsulated in IP */
 207
 208                 "MICP",       /**< Mobile Int.ing control */
 209                 "SCCSP",      /**< Semaphore Comm. security */
 210                 "ETHERIP",    /**< Ethernet IP encapsulation */
 211                 "ENCAP",      /**< encapsulation header */
 212                 "AES",        /**< any private encr. scheme */
 213
 214                 "GMTP",       /**< GMTP */
 215                 "IPCOMP",     /**< payload compression (IPComp) */
 216                 "UNASSIGNED",
 217                 "UNASSIGNED",
 218                 "PIM",        /**< Protocol Independent Mcast */
 219         };
 220
 221         if (ip_proto < sizeof(ip_proto_names) / sizeof(ip_proto_names[0]))
 222                 return ip_proto_names[ip_proto];
 223         switch (ip_proto) {
 224 #ifdef IPPROTO_PGM
 225         case IPPROTO_PGM:  /**< PGM */
 226                 return "PGM";
 227 #endif
 228         case IPPROTO_SCTP:  /**< Stream Control Transport Protocol */
 229                 return "SCTP";
 230 #ifdef IPPROTO_DIVERT
 231         case IPPROTO_DIVERT: /**< divert pseudo-protocol */
 232                 return "DIVERT";
 233 #endif
 234         case IPPROTO_RAW: /**< raw IP packet */
 235                 return "RAW";
 236         default:
 237                 break;
 238         }
 239         return "UNASSIGNED";
 240 }
 241
 242 static void
 243 ipv4_addr_to_dot(uint32_t be_ipv4_addr, char *buf)
 244 {
 245         uint32_t ipv4_addr;
 246
 247         ipv4_addr = rte_be_to_cpu_32(be_ipv4_addr);
 248         sprintf(buf, "%d.%d.%d.%d", (ipv4_addr >> 24) & 0xFF,
 249                 (ipv4_addr >> 16) & 0xFF, (ipv4_addr >> 8) & 0xFF,
 250                 ipv4_addr & 0xFF);
 251 }
 252
 253 static void
 254 ether_addr_dump(const char *what, const struct ether_addr *ea)
 255 {
 256         char buf[ETHER_ADDR_FMT_SIZE];
 257
 258         ether_format_addr(buf, ETHER_ADDR_FMT_SIZE, ea);
 259         if (what)
 260                 printf("%s", what);
 261         printf("%s", buf);
 262 }
 263
 264 static void
 265 ipv4_addr_dump(const char *what, uint32_t be_ipv4_addr)
 266 {
 267         char buf[16];
 268
 269         ipv4_addr_to_dot(be_ipv4_addr, buf);
 270         if (what)
 271                 printf("%s", what);
 272         printf("%s", buf);
 273 }
 274
 275 static uint16_t
 276 ipv4_hdr_cksum(struct ipv4_hdr *ip_h)
 277 {
 278         uint16_t *v16_h;
 279         uint32_t ip_cksum;
 280
 281         /*
 282          * Compute the sum of successive 16-bit words of the IPv4 header,
 283          * skipping the checksum field of the header.
 284          */
 285         v16_h = (unaligned_uint16_t *) ip_h;
 286         ip_cksum = v16_h[0] + v16_h[1] + v16_h[2] + v16_h[3] +
 287                 v16_h[4] + v16_h[6] + v16_h[7] + v16_h[8] + v16_h[9];
 288
 289         /* reduce 32 bit checksum to 16 bits and complement it */
 290         ip_cksum = (ip_cksum & 0xffff) + (ip_cksum >> 16);
 291         ip_cksum = (ip_cksum & 0xffff) + (ip_cksum >> 16);
 292         ip_cksum = (~ip_cksum) & 0x0000FFFF;
 293         return (ip_cksum == 0) ? 0xFFFF : (uint16_t) ip_cksum;
 294 }
 295
 296 #define is_multicast_ipv4_addr(ipv4_addr) \
 297         (((rte_be_to_cpu_32((ipv4_addr)) >> 24) & 0x000000FF) == 0xE0)
 298
 299 /*
 300  * Receive a burst of packets, lookup for ICMP echo requets, and, if any,
 301  * send back ICMP echo replies.
 302  */
 303 static void
 304 reply_to_icmp_echo_rqsts(struct fwd_stream *fs)
 305 {
 306         struct rte_mbuf *pkts_burst[MAX_PKT_BURST];
 307         struct rte_mbuf *pkt;
 308         struct ether_hdr *eth_h;
 309         struct vlan_hdr *vlan_h;
 310         struct arp_hdr  *arp_h;
 311         struct ipv4_hdr *ip_h;
 312         struct icmp_hdr *icmp_h;
 313         struct ether_addr eth_addr;
 314         uint32_t ip_addr;
 315         uint16_t nb_rx;
 316         uint16_t nb_tx;
 317         uint16_t nb_replies;
 318         uint16_t eth_type;
 319         uint16_t vlan_id;
 320         uint16_t arp_op;
 321         uint16_t arp_pro;
 322         uint32_t cksum;
 323         uint8_t  i;
 324         int l2_len;
 325 #ifdef RTE_TEST_PMD_RECORD_CORE_CYCLES
 326         uint64_t start_tsc;
 327         uint64_t end_tsc;
 328         uint64_t core_cycles;
 329 #endif
 330
 331 #ifdef RTE_TEST_PMD_RECORD_CORE_CYCLES
 332         start_tsc = rte_rdtsc();
 333 #endif
 334
 335         /*
 336          * First, receive a burst of packets.
 337          */
 338         nb_rx = rte_eth_rx_burst(fs->rx_port, fs->rx_queue, pkts_burst,
 339                                  nb_pkt_per_burst);
 340         if (unlikely(nb_rx == 0))
 341                 return;
 342
 343 #ifdef RTE_TEST_PMD_RECORD_BURST_STATS
 344         fs->rx_burst_stats.pkt_burst_spread[nb_rx]++;
 345 #endif
 346         fs->rx_packets += nb_rx;
 347         nb_replies = 0;
 348         for (i = 0; i < nb_rx; i++) {
 349                 pkt = pkts_burst[i];
 350                 eth_h = rte_pktmbuf_mtod(pkt, struct ether_hdr *);
 351                 eth_type = RTE_BE_TO_CPU_16(eth_h->ether_type);
 352                 l2_len = sizeof(struct ether_hdr);
 353                 if (verbose_level > 0) {
 354                         printf("\nPort %d pkt-len=%u nb-segs=%u\n",
 355                                fs->rx_port, pkt->pkt_len, pkt->nb_segs);
 356                         ether_addr_dump("  ETH:  src=", &eth_h->s_addr);
 357                         ether_addr_dump(" dst=", &eth_h->d_addr);
 358                 }
 359                 if (eth_type == ETHER_TYPE_VLAN) {
 360                         vlan_h = (struct vlan_hdr *)
 361                                 ((char *)eth_h + sizeof(struct ether_hdr));
 362                         l2_len  += sizeof(struct vlan_hdr);
 363                         eth_type = rte_be_to_cpu_16(vlan_h->eth_proto);
 364                         if (verbose_level > 0) {
 365                                 vlan_id = rte_be_to_cpu_16(vlan_h->vlan_tci)
 366                                         & 0xFFF;
 367                                 printf(" [vlan id=%u]", vlan_id);
 368                         }
 369                 }
 370                 if (verbose_level > 0) {
 371                         printf(" type=0x%04x\n", eth_type);
 372                 }
 373
 374                 /* Reply to ARP requests */
 375                 if (eth_type == ETHER_TYPE_ARP) {
 376                         arp_h = (struct arp_hdr *) ((char *)eth_h + l2_len);
 377                         arp_op = RTE_BE_TO_CPU_16(arp_h->arp_op);
 378                         arp_pro = RTE_BE_TO_CPU_16(arp_h->arp_pro);
 379                         if (verbose_level > 0) {
 380                                 printf("  ARP:  hrd=%d proto=0x%04x hln=%d "
 381                                        "pln=%d op=%u (%s)\n",
 382                                        RTE_BE_TO_CPU_16(arp_h->arp_hrd),
 383                                        arp_pro, arp_h->arp_hln,
 384                                        arp_h->arp_pln, arp_op,
 385                                        arp_op_name(arp_op));
 386                         }
 387                         if ((RTE_BE_TO_CPU_16(arp_h->arp_hrd) !=
 388                              ARP_HRD_ETHER) ||
 389                             (arp_pro != ETHER_TYPE_IPv4) ||
 390                             (arp_h->arp_hln != 6) ||
 391                             (arp_h->arp_pln != 4)
 392                             ) {
 393                                 rte_pktmbuf_free(pkt);
 394                                 if (verbose_level > 0)
 395                                         printf("\n");
 396                                 continue;
 397                         }
 398                         if (verbose_level > 0) {
 399                                 ether_addr_copy(&arp_h->arp_data.arp_sha, &eth_addr);
 400                                 ether_addr_dump("        sha=", &eth_addr);
 401                                 ip_addr = arp_h->arp_data.arp_sip;
 402                                 ipv4_addr_dump(" sip=", ip_addr);
 403                                 printf("\n");
 404                                 ether_addr_copy(&arp_h->arp_data.arp_tha, &eth_addr);
 405                                 ether_addr_dump("        tha=", &eth_addr);
 406                                 ip_addr = arp_h->arp_data.arp_tip;
 407                                 ipv4_addr_dump(" tip=", ip_addr);
 408                                 printf("\n");
 409                         }
 410                         if (arp_op != ARP_OP_REQUEST) {
 411                                 rte_pktmbuf_free(pkt);
 412                                 continue;
 413                         }
 414
 415                         /*
 416                          * Build ARP reply.
 417                          */
 418
 419                         /* Use source MAC address as destination MAC address. */
 420                         ether_addr_copy(&eth_h->s_addr, &eth_h->d_addr);
 421                         /* Set source MAC address with MAC address of TX port */
 422                         ether_addr_copy(&ports[fs->tx_port].eth_addr,
 423                                         &eth_h->s_addr);
 424
 425                         arp_h->arp_op = rte_cpu_to_be_16(ARP_OP_REPLY);
 426                         ether_addr_copy(&arp_h->arp_data.arp_tha, &eth_addr);
 427                         ether_addr_copy(&arp_h->arp_data.arp_sha, &arp_h->arp_data.arp_tha);
 428                         ether_addr_copy(&eth_h->s_addr, &arp_h->arp_data.arp_sha);
 429
 430                         /* Swap IP addresses in ARP payload */
 431                         ip_addr = arp_h->arp_data.arp_sip;
 432                         arp_h->arp_data.arp_sip = arp_h->arp_data.arp_tip;
 433                         arp_h->arp_data.arp_tip = ip_addr;
 434                         pkts_burst[nb_replies++] = pkt;
 435                         continue;
 436                 }
 437
 438                 if (eth_type != ETHER_TYPE_IPv4) {
 439                         rte_pktmbuf_free(pkt);
 440                         continue;
 441                 }
 442                 ip_h = (struct ipv4_hdr *) ((char *)eth_h + l2_len);
 443                 if (verbose_level > 0) {
 444                         ipv4_addr_dump("  IPV4: src=", ip_h->src_addr);
 445                         ipv4_addr_dump(" dst=", ip_h->dst_addr);
 446                         printf(" proto=%d (%s)\n",
 447                                ip_h->next_proto_id,
 448                                ip_proto_name(ip_h->next_proto_id));
 449                 }
 450
 451                 /*
 452                  * Check if packet is a ICMP echo request.
 453                  */
 454                 icmp_h = (struct icmp_hdr *) ((char *)ip_h +
 455                                               sizeof(struct ipv4_hdr));
 456                 if (! ((ip_h->next_proto_id == IPPROTO_ICMP) &&
 457                        (icmp_h->icmp_type == IP_ICMP_ECHO_REQUEST) &&
 458                        (icmp_h->icmp_code == 0))) {
 459                         rte_pktmbuf_free(pkt);
 460                         continue;
 461                 }
 462
 463                 if (verbose_level > 0)
 464                         printf("  ICMP: echo request seq id=%d\n",
 465                                rte_be_to_cpu_16(icmp_h->icmp_seq_nb));
 466
 467                 /*
 468                  * Prepare ICMP echo reply to be sent back.
 469                  * - switch ethernet source and destinations addresses,
 470                  * - use the request IP source address as the reply IP
 471                  *    destination address,
 472                  * - if the request IP destination address is a multicast
 473                  *   address:
 474                  *     - choose a reply IP source address different from the
 475                  *       request IP source address,
 476                  *     - re-compute the IP header checksum.
 477                  *   Otherwise:
 478                  *     - switch the request IP source and destination
 479                  *       addresses in the reply IP header,
 480                  *     - keep the IP header checksum unchanged.
 481                  * - set IP_ICMP_ECHO_REPLY in ICMP header.
 482                  * ICMP checksum is computed by assuming it is valid in the
 483                  * echo request and not verified.
 484                  */
 485                 ether_addr_copy(&eth_h->s_addr, &eth_addr);
 486                 ether_addr_copy(&eth_h->d_addr, &eth_h->s_addr);
 487                 ether_addr_copy(&eth_addr, &eth_h->d_addr);
 488                 ip_addr = ip_h->src_addr;
 489                 if (is_multicast_ipv4_addr(ip_h->dst_addr)) {
 490                         uint32_t ip_src;
 491
 492                         ip_src = rte_be_to_cpu_32(ip_addr);
 493                         if ((ip_src & 0x00000003) == 1)
 494                                 ip_src = (ip_src & 0xFFFFFFFC) | 0x00000002;
 495                         else
 496                                 ip_src = (ip_src & 0xFFFFFFFC) | 0x00000001;
 497                         ip_h->src_addr = rte_cpu_to_be_32(ip_src);
 498                         ip_h->dst_addr = ip_addr;
 499                         ip_h->hdr_checksum = ipv4_hdr_cksum(ip_h);
 500                 } else {
 501                         ip_h->src_addr = ip_h->dst_addr;
 502                         ip_h->dst_addr = ip_addr;
 503                 }
 504                 icmp_h->icmp_type = IP_ICMP_ECHO_REPLY;
 505                 cksum = ~icmp_h->icmp_cksum & 0xffff;
 506                 cksum += ~htons(IP_ICMP_ECHO_REQUEST << 8) & 0xffff;
 507                 cksum += htons(IP_ICMP_ECHO_REPLY << 8);
 508                 cksum = (cksum & 0xffff) + (cksum >> 16);
 509                 cksum = (cksum & 0xffff) + (cksum >> 16);
 510                 icmp_h->icmp_cksum = ~cksum;
 511                 pkts_burst[nb_replies++] = pkt;
 512         }
 513
 514         /* Send back ICMP echo replies, if any. */
 515         if (nb_replies > 0) {
 516                 nb_tx = rte_eth_tx_burst(fs->tx_port, fs->tx_queue, pkts_burst,
 517                                          nb_replies);
 518                 fs->tx_packets += nb_tx;
 519 #ifdef RTE_TEST_PMD_RECORD_BURST_STATS
 520                 fs->tx_burst_stats.pkt_burst_spread[nb_tx]++;
 521 #endif
 522                 if (unlikely(nb_tx < nb_replies)) {
 523                         fs->fwd_dropped += (nb_replies - nb_tx);
 524                         do {
 525                                 rte_pktmbuf_free(pkts_burst[nb_tx]);
 526                         } while (++nb_tx < nb_replies);
 527                 }
 528         }
 529
 530 #ifdef RTE_TEST_PMD_RECORD_CORE_CYCLES
 531         end_tsc = rte_rdtsc();
 532         core_cycles = (end_tsc - start_tsc);
 533         fs->core_cycles = (uint64_t) (fs->core_cycles + core_cycles);
 534 #endif
 535 }
 536
 537 struct fwd_engine icmp_echo_engine = {
 538         .fwd_mode_name  = "icmpecho",
 539         .port_fwd_begin = NULL,
 540         .port_fwd_end   = NULL,
 541         .packet_fwd     = reply_to_icmp_echo_rqsts,
 542 };