qemu/tests/vhost-user-bridge.c
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   1/*
   2 * Vhost User Bridge
   3 *
   4 * Copyright (c) 2015 Red Hat, Inc.
   5 *
   6 * Authors:
   7 *  Victor Kaplansky <victork@redhat.com>
   8 *
   9 * This work is licensed under the terms of the GNU GPL, version 2 or
  10 * later.  See the COPYING file in the top-level directory.
  11 */
  12
  13/*
  14 * TODO:
  15 *     - main should get parameters from the command line.
  16 *     - implement all request handlers. Still not implemented:
  17 *          vubr_get_queue_num_exec()
  18 *          vubr_send_rarp_exec()
  19 *     - test for broken requests and virtqueue.
  20 *     - implement features defined by Virtio 1.0 spec.
  21 *     - support mergeable buffers and indirect descriptors.
  22 *     - implement clean shutdown.
  23 *     - implement non-blocking writes to UDP backend.
  24 *     - implement polling strategy.
  25 *     - implement clean starting/stopping of vq processing
  26 *     - implement clean starting/stopping of used and buffers
  27 *       dirty page logging.
  28 */
  29
  30#define _FILE_OFFSET_BITS 64
  31
  32#include "qemu/osdep.h"
  33#include <sys/socket.h>
  34#include <sys/un.h>
  35#include <sys/unistd.h>
  36#include <sys/eventfd.h>
  37#include <arpa/inet.h>
  38#include <netdb.h>
  39#include <linux/vhost.h>
  40
  41#include "qemu/atomic.h"
  42#include "standard-headers/linux/virtio_net.h"
  43#include "standard-headers/linux/virtio_ring.h"
  44
  45#define VHOST_USER_BRIDGE_DEBUG 1
  46
  47#define DPRINT(...) \
  48    do { \
  49        if (VHOST_USER_BRIDGE_DEBUG) { \
  50            printf(__VA_ARGS__); \
  51        } \
  52    } while (0)
  53
  54typedef void (*CallbackFunc)(int sock, void *ctx);
  55
  56typedef struct Event {
  57    void *ctx;
  58    CallbackFunc callback;
  59} Event;
  60
  61typedef struct Dispatcher {
  62    int max_sock;
  63    fd_set fdset;
  64    Event events[FD_SETSIZE];
  65} Dispatcher;
  66
  67static void
  68vubr_die(const char *s)
  69{
  70    perror(s);
  71    exit(1);
  72}
  73
  74static int
  75dispatcher_init(Dispatcher *dispr)
  76{
  77    FD_ZERO(&dispr->fdset);
  78    dispr->max_sock = -1;
  79    return 0;
  80}
  81
  82static int
  83dispatcher_add(Dispatcher *dispr, int sock, void *ctx, CallbackFunc cb)
  84{
  85    if (sock >= FD_SETSIZE) {
  86        fprintf(stderr,
  87                "Error: Failed to add new event. sock %d should be less than %d\n",
  88                sock, FD_SETSIZE);
  89        return -1;
  90    }
  91
  92    dispr->events[sock].ctx = ctx;
  93    dispr->events[sock].callback = cb;
  94
  95    FD_SET(sock, &dispr->fdset);
  96    if (sock > dispr->max_sock) {
  97        dispr->max_sock = sock;
  98    }
  99    DPRINT("Added sock %d for watching. max_sock: %d\n",
 100           sock, dispr->max_sock);
 101    return 0;
 102}
 103
 104/* dispatcher_remove() is not currently in use but may be useful
 105 * in the future. */
 106static int
 107dispatcher_remove(Dispatcher *dispr, int sock)
 108{
 109    if (sock >= FD_SETSIZE) {
 110        fprintf(stderr,
 111                "Error: Failed to remove event. sock %d should be less than %d\n",
 112                sock, FD_SETSIZE);
 113        return -1;
 114    }
 115
 116    FD_CLR(sock, &dispr->fdset);
 117    DPRINT("Sock %d removed from dispatcher watch.\n", sock);
 118    return 0;
 119}
 120
 121/* timeout in us */
 122static int
 123dispatcher_wait(Dispatcher *dispr, uint32_t timeout)
 124{
 125    struct timeval tv;
 126    tv.tv_sec = timeout / 1000000;
 127    tv.tv_usec = timeout % 1000000;
 128
 129    fd_set fdset = dispr->fdset;
 130
 131    /* wait until some of sockets become readable. */
 132    int rc = select(dispr->max_sock + 1, &fdset, 0, 0, &tv);
 133
 134    if (rc == -1) {
 135        vubr_die("select");
 136    }
 137
 138    /* Timeout */
 139    if (rc == 0) {
 140        return 0;
 141    }
 142
 143    /* Now call callback for every ready socket. */
 144
 145    int sock;
 146    for (sock = 0; sock < dispr->max_sock + 1; sock++) {
 147        /* The callback on a socket can remove other sockets from the
 148         * dispatcher, thus we have to check that the socket is
 149         * still not removed from dispatcher's list
 150         */
 151        if (FD_ISSET(sock, &fdset) && FD_ISSET(sock, &dispr->fdset)) {
 152            Event *e = &dispr->events[sock];
 153            e->callback(sock, e->ctx);
 154        }
 155    }
 156
 157    return 0;
 158}
 159
 160typedef struct VubrVirtq {
 161    int call_fd;
 162    int kick_fd;
 163    uint32_t size;
 164    uint16_t last_avail_index;
 165    uint16_t last_used_index;
 166    struct vring_desc *desc;
 167    struct vring_avail *avail;
 168    struct vring_used *used;
 169    uint64_t log_guest_addr;
 170    int enable;
 171} VubrVirtq;
 172
 173/* Based on qemu/hw/virtio/vhost-user.c */
 174
 175#define VHOST_MEMORY_MAX_NREGIONS    8
 176#define VHOST_USER_F_PROTOCOL_FEATURES 30
 177/* v1.0 compliant. */
 178#define VIRTIO_F_VERSION_1              32
 179
 180#define VHOST_LOG_PAGE 4096
 181
 182enum VhostUserProtocolFeature {
 183    VHOST_USER_PROTOCOL_F_MQ = 0,
 184    VHOST_USER_PROTOCOL_F_LOG_SHMFD = 1,
 185    VHOST_USER_PROTOCOL_F_RARP = 2,
 186
 187    VHOST_USER_PROTOCOL_F_MAX
 188};
 189
 190#define VHOST_USER_PROTOCOL_FEATURE_MASK ((1 << VHOST_USER_PROTOCOL_F_MAX) - 1)
 191
 192typedef enum VhostUserRequest {
 193    VHOST_USER_NONE = 0,
 194    VHOST_USER_GET_FEATURES = 1,
 195    VHOST_USER_SET_FEATURES = 2,
 196    VHOST_USER_SET_OWNER = 3,
 197    VHOST_USER_RESET_OWNER = 4,
 198    VHOST_USER_SET_MEM_TABLE = 5,
 199    VHOST_USER_SET_LOG_BASE = 6,
 200    VHOST_USER_SET_LOG_FD = 7,
 201    VHOST_USER_SET_VRING_NUM = 8,
 202    VHOST_USER_SET_VRING_ADDR = 9,
 203    VHOST_USER_SET_VRING_BASE = 10,
 204    VHOST_USER_GET_VRING_BASE = 11,
 205    VHOST_USER_SET_VRING_KICK = 12,
 206    VHOST_USER_SET_VRING_CALL = 13,
 207    VHOST_USER_SET_VRING_ERR = 14,
 208    VHOST_USER_GET_PROTOCOL_FEATURES = 15,
 209    VHOST_USER_SET_PROTOCOL_FEATURES = 16,
 210    VHOST_USER_GET_QUEUE_NUM = 17,
 211    VHOST_USER_SET_VRING_ENABLE = 18,
 212    VHOST_USER_SEND_RARP = 19,
 213    VHOST_USER_MAX
 214} VhostUserRequest;
 215
 216typedef struct VhostUserMemoryRegion {
 217    uint64_t guest_phys_addr;
 218    uint64_t memory_size;
 219    uint64_t userspace_addr;
 220    uint64_t mmap_offset;
 221} VhostUserMemoryRegion;
 222
 223typedef struct VhostUserMemory {
 224    uint32_t nregions;
 225    uint32_t padding;
 226    VhostUserMemoryRegion regions[VHOST_MEMORY_MAX_NREGIONS];
 227} VhostUserMemory;
 228
 229typedef struct VhostUserLog {
 230    uint64_t mmap_size;
 231    uint64_t mmap_offset;
 232} VhostUserLog;
 233
 234typedef struct VhostUserMsg {
 235    VhostUserRequest request;
 236
 237#define VHOST_USER_VERSION_MASK     (0x3)
 238#define VHOST_USER_REPLY_MASK       (0x1<<2)
 239    uint32_t flags;
 240    uint32_t size; /* the following payload size */
 241    union {
 242#define VHOST_USER_VRING_IDX_MASK   (0xff)
 243#define VHOST_USER_VRING_NOFD_MASK  (0x1<<8)
 244        uint64_t u64;
 245        struct vhost_vring_state state;
 246        struct vhost_vring_addr addr;
 247        VhostUserMemory memory;
 248        VhostUserLog log;
 249    } payload;
 250    int fds[VHOST_MEMORY_MAX_NREGIONS];
 251    int fd_num;
 252} QEMU_PACKED VhostUserMsg;
 253
 254#define VHOST_USER_HDR_SIZE offsetof(VhostUserMsg, payload.u64)
 255
 256/* The version of the protocol we support */
 257#define VHOST_USER_VERSION    (0x1)
 258
 259#define MAX_NR_VIRTQUEUE (8)
 260
 261typedef struct VubrDevRegion {
 262    /* Guest Physical address. */
 263    uint64_t gpa;
 264    /* Memory region size. */
 265    uint64_t size;
 266    /* QEMU virtual address (userspace). */
 267    uint64_t qva;
 268    /* Starting offset in our mmaped space. */
 269    uint64_t mmap_offset;
 270    /* Start address of mmaped space. */
 271    uint64_t mmap_addr;
 272} VubrDevRegion;
 273
 274typedef struct VubrDev {
 275    int sock;
 276    Dispatcher dispatcher;
 277    uint32_t nregions;
 278    VubrDevRegion regions[VHOST_MEMORY_MAX_NREGIONS];
 279    VubrVirtq vq[MAX_NR_VIRTQUEUE];
 280    int log_call_fd;
 281    uint64_t log_size;
 282    uint8_t *log_table;
 283    int backend_udp_sock;
 284    struct sockaddr_in backend_udp_dest;
 285    int ready;
 286    uint64_t features;
 287    int hdrlen;
 288} VubrDev;
 289
 290static const char *vubr_request_str[] = {
 291    [VHOST_USER_NONE]                   =  "VHOST_USER_NONE",
 292    [VHOST_USER_GET_FEATURES]           =  "VHOST_USER_GET_FEATURES",
 293    [VHOST_USER_SET_FEATURES]           =  "VHOST_USER_SET_FEATURES",
 294    [VHOST_USER_SET_OWNER]              =  "VHOST_USER_SET_OWNER",
 295    [VHOST_USER_RESET_OWNER]           =  "VHOST_USER_RESET_OWNER",
 296    [VHOST_USER_SET_MEM_TABLE]          =  "VHOST_USER_SET_MEM_TABLE",
 297    [VHOST_USER_SET_LOG_BASE]           =  "VHOST_USER_SET_LOG_BASE",
 298    [VHOST_USER_SET_LOG_FD]             =  "VHOST_USER_SET_LOG_FD",
 299    [VHOST_USER_SET_VRING_NUM]          =  "VHOST_USER_SET_VRING_NUM",
 300    [VHOST_USER_SET_VRING_ADDR]         =  "VHOST_USER_SET_VRING_ADDR",
 301    [VHOST_USER_SET_VRING_BASE]         =  "VHOST_USER_SET_VRING_BASE",
 302    [VHOST_USER_GET_VRING_BASE]         =  "VHOST_USER_GET_VRING_BASE",
 303    [VHOST_USER_SET_VRING_KICK]         =  "VHOST_USER_SET_VRING_KICK",
 304    [VHOST_USER_SET_VRING_CALL]         =  "VHOST_USER_SET_VRING_CALL",
 305    [VHOST_USER_SET_VRING_ERR]          =  "VHOST_USER_SET_VRING_ERR",
 306    [VHOST_USER_GET_PROTOCOL_FEATURES]  =  "VHOST_USER_GET_PROTOCOL_FEATURES",
 307    [VHOST_USER_SET_PROTOCOL_FEATURES]  =  "VHOST_USER_SET_PROTOCOL_FEATURES",
 308    [VHOST_USER_GET_QUEUE_NUM]          =  "VHOST_USER_GET_QUEUE_NUM",
 309    [VHOST_USER_SET_VRING_ENABLE]       =  "VHOST_USER_SET_VRING_ENABLE",
 310    [VHOST_USER_SEND_RARP]              =  "VHOST_USER_SEND_RARP",
 311    [VHOST_USER_MAX]                    =  "VHOST_USER_MAX",
 312};
 313
 314static void
 315print_buffer(uint8_t *buf, size_t len)
 316{
 317    int i;
 318    printf("Raw buffer:\n");
 319    for (i = 0; i < len; i++) {
 320        if (i % 16 == 0) {
 321            printf("\n");
 322        }
 323        if (i % 4 == 0) {
 324            printf("   ");
 325        }
 326        printf("%02x ", buf[i]);
 327    }
 328    printf("\n............................................................\n");
 329}
 330
 331/* Translate guest physical address to our virtual address.  */
 332static uint64_t
 333gpa_to_va(VubrDev *dev, uint64_t guest_addr)
 334{
 335    int i;
 336
 337    /* Find matching memory region.  */
 338    for (i = 0; i < dev->nregions; i++) {
 339        VubrDevRegion *r = &dev->regions[i];
 340
 341        if ((guest_addr >= r->gpa) && (guest_addr < (r->gpa + r->size))) {
 342            return guest_addr - r->gpa + r->mmap_addr + r->mmap_offset;
 343        }
 344    }
 345
 346    assert(!"address not found in regions");
 347    return 0;
 348}
 349
 350/* Translate qemu virtual address to our virtual address.  */
 351static uint64_t
 352qva_to_va(VubrDev *dev, uint64_t qemu_addr)
 353{
 354    int i;
 355
 356    /* Find matching memory region.  */
 357    for (i = 0; i < dev->nregions; i++) {
 358        VubrDevRegion *r = &dev->regions[i];
 359
 360        if ((qemu_addr >= r->qva) && (qemu_addr < (r->qva + r->size))) {
 361            return qemu_addr - r->qva + r->mmap_addr + r->mmap_offset;
 362        }
 363    }
 364
 365    assert(!"address not found in regions");
 366    return 0;
 367}
 368
 369static void
 370vubr_message_read(int conn_fd, VhostUserMsg *vmsg)
 371{
 372    char control[CMSG_SPACE(VHOST_MEMORY_MAX_NREGIONS * sizeof(int))] = { };
 373    struct iovec iov = {
 374        .iov_base = (char *)vmsg,
 375        .iov_len = VHOST_USER_HDR_SIZE,
 376    };
 377    struct msghdr msg = {
 378        .msg_iov = &iov,
 379        .msg_iovlen = 1,
 380        .msg_control = control,
 381        .msg_controllen = sizeof(control),
 382    };
 383    size_t fd_size;
 384    struct cmsghdr *cmsg;
 385    int rc;
 386
 387    rc = recvmsg(conn_fd, &msg, 0);
 388
 389    if (rc == 0) {
 390        vubr_die("recvmsg");
 391        fprintf(stderr, "Peer disconnected.\n");
 392        exit(1);
 393    }
 394    if (rc < 0) {
 395        vubr_die("recvmsg");
 396    }
 397
 398    vmsg->fd_num = 0;
 399    for (cmsg = CMSG_FIRSTHDR(&msg);
 400         cmsg != NULL;
 401         cmsg = CMSG_NXTHDR(&msg, cmsg))
 402    {
 403        if (cmsg->cmsg_level == SOL_SOCKET && cmsg->cmsg_type == SCM_RIGHTS) {
 404            fd_size = cmsg->cmsg_len - CMSG_LEN(0);
 405            vmsg->fd_num = fd_size / sizeof(int);
 406            memcpy(vmsg->fds, CMSG_DATA(cmsg), fd_size);
 407            break;
 408        }
 409    }
 410
 411    if (vmsg->size > sizeof(vmsg->payload)) {
 412        fprintf(stderr,
 413                "Error: too big message request: %d, size: vmsg->size: %u, "
 414                "while sizeof(vmsg->payload) = %zu\n",
 415                vmsg->request, vmsg->size, sizeof(vmsg->payload));
 416        exit(1);
 417    }
 418
 419    if (vmsg->size) {
 420        rc = read(conn_fd, &vmsg->payload, vmsg->size);
 421        if (rc == 0) {
 422            vubr_die("recvmsg");
 423            fprintf(stderr, "Peer disconnected.\n");
 424            exit(1);
 425        }
 426        if (rc < 0) {
 427            vubr_die("recvmsg");
 428        }
 429
 430        assert(rc == vmsg->size);
 431    }
 432}
 433
 434static void
 435vubr_message_write(int conn_fd, VhostUserMsg *vmsg)
 436{
 437    int rc;
 438
 439    do {
 440        rc = write(conn_fd, vmsg, VHOST_USER_HDR_SIZE + vmsg->size);
 441    } while (rc < 0 && errno == EINTR);
 442
 443    if (rc < 0) {
 444        vubr_die("write");
 445    }
 446}
 447
 448static void
 449vubr_backend_udp_sendbuf(VubrDev *dev, uint8_t *buf, size_t len)
 450{
 451    int slen = sizeof(struct sockaddr_in);
 452
 453    if (sendto(dev->backend_udp_sock, buf, len, 0,
 454               (struct sockaddr *) &dev->backend_udp_dest, slen) == -1) {
 455        vubr_die("sendto()");
 456    }
 457}
 458
 459static int
 460vubr_backend_udp_recvbuf(VubrDev *dev, uint8_t *buf, size_t buflen)
 461{
 462    int slen = sizeof(struct sockaddr_in);
 463    int rc;
 464
 465    rc = recvfrom(dev->backend_udp_sock, buf, buflen, 0,
 466                  (struct sockaddr *) &dev->backend_udp_dest,
 467                  (socklen_t *)&slen);
 468    if (rc == -1) {
 469        vubr_die("recvfrom()");
 470    }
 471
 472    return rc;
 473}
 474
 475static void
 476vubr_consume_raw_packet(VubrDev *dev, uint8_t *buf, uint32_t len)
 477{
 478    int hdrlen = dev->hdrlen;
 479    DPRINT("    hdrlen = %d\n", dev->hdrlen);
 480
 481    if (VHOST_USER_BRIDGE_DEBUG) {
 482        print_buffer(buf, len);
 483    }
 484    vubr_backend_udp_sendbuf(dev, buf + hdrlen, len - hdrlen);
 485}
 486
 487/* Kick the log_call_fd if required. */
 488static void
 489vubr_log_kick(VubrDev *dev)
 490{
 491    if (dev->log_call_fd != -1) {
 492        DPRINT("Kicking the QEMU's log...\n");
 493        eventfd_write(dev->log_call_fd, 1);
 494    }
 495}
 496
 497/* Kick the guest if necessary. */
 498static void
 499vubr_virtqueue_kick(VubrVirtq *vq)
 500{
 501    if (!(vq->avail->flags & VRING_AVAIL_F_NO_INTERRUPT)) {
 502        DPRINT("Kicking the guest...\n");
 503        eventfd_write(vq->call_fd, 1);
 504    }
 505}
 506
 507static void
 508vubr_log_page(uint8_t *log_table, uint64_t page)
 509{
 510    DPRINT("Logged dirty guest page: %"PRId64"\n", page);
 511    atomic_or(&log_table[page / 8], 1 << (page % 8));
 512}
 513
 514static void
 515vubr_log_write(VubrDev *dev, uint64_t address, uint64_t length)
 516{
 517    uint64_t page;
 518
 519    if (!(dev->features & (1ULL << VHOST_F_LOG_ALL)) ||
 520        !dev->log_table || !length) {
 521        return;
 522    }
 523
 524    assert(dev->log_size > ((address + length - 1) / VHOST_LOG_PAGE / 8));
 525
 526    page = address / VHOST_LOG_PAGE;
 527    while (page * VHOST_LOG_PAGE < address + length) {
 528        vubr_log_page(dev->log_table, page);
 529        page += VHOST_LOG_PAGE;
 530    }
 531    vubr_log_kick(dev);
 532}
 533
 534static void
 535vubr_post_buffer(VubrDev *dev, VubrVirtq *vq, uint8_t *buf, int32_t len)
 536{
 537    struct vring_desc *desc = vq->desc;
 538    struct vring_avail *avail = vq->avail;
 539    struct vring_used *used = vq->used;
 540    uint64_t log_guest_addr = vq->log_guest_addr;
 541    int32_t remaining_len = len;
 542
 543    unsigned int size = vq->size;
 544
 545    uint16_t avail_index = atomic_mb_read(&avail->idx);
 546
 547    /* We check the available descriptors before posting the
 548     * buffer, so here we assume that enough available
 549     * descriptors. */
 550    assert(vq->last_avail_index != avail_index);
 551    uint16_t a_index = vq->last_avail_index % size;
 552    uint16_t u_index = vq->last_used_index % size;
 553    uint16_t d_index = avail->ring[a_index];
 554
 555    int i = d_index;
 556    uint32_t written_len = 0;
 557
 558    do {
 559        DPRINT("Post packet to guest on vq:\n");
 560        DPRINT("    size             = %d\n", vq->size);
 561        DPRINT("    last_avail_index = %d\n", vq->last_avail_index);
 562        DPRINT("    last_used_index  = %d\n", vq->last_used_index);
 563        DPRINT("    a_index = %d\n", a_index);
 564        DPRINT("    u_index = %d\n", u_index);
 565        DPRINT("    d_index = %d\n", d_index);
 566        DPRINT("    desc[%d].addr    = 0x%016"PRIx64"\n", i, desc[i].addr);
 567        DPRINT("    desc[%d].len     = %d\n", i, desc[i].len);
 568        DPRINT("    desc[%d].flags   = %d\n", i, desc[i].flags);
 569        DPRINT("    avail->idx = %d\n", avail_index);
 570        DPRINT("    used->idx  = %d\n", used->idx);
 571
 572        if (!(desc[i].flags & VRING_DESC_F_WRITE)) {
 573            /* FIXME: we should find writable descriptor. */
 574            fprintf(stderr, "Error: descriptor is not writable. Exiting.\n");
 575            exit(1);
 576        }
 577
 578        void *chunk_start = (void *)(uintptr_t)gpa_to_va(dev, desc[i].addr);
 579        uint32_t chunk_len = desc[i].len;
 580        uint32_t chunk_write_len = MIN(remaining_len, chunk_len);
 581
 582        memcpy(chunk_start, buf + written_len, chunk_write_len);
 583        vubr_log_write(dev, desc[i].addr, chunk_write_len);
 584        remaining_len -= chunk_write_len;
 585        written_len += chunk_write_len;
 586
 587        if ((remaining_len == 0) || !(desc[i].flags & VRING_DESC_F_NEXT)) {
 588            break;
 589        }
 590
 591        i = desc[i].next;
 592    } while (1);
 593
 594    if (remaining_len > 0) {
 595            fprintf(stderr,
 596                    "Too long packet for RX, remaining_len = %d, Dropping...\n",
 597                    remaining_len);
 598            return;
 599    }
 600
 601    /* Add descriptor to the used ring. */
 602    used->ring[u_index].id = d_index;
 603    used->ring[u_index].len = len;
 604    vubr_log_write(dev,
 605                   log_guest_addr + offsetof(struct vring_used, ring[u_index]),
 606                   sizeof(used->ring[u_index]));
 607
 608    vq->last_avail_index++;
 609    vq->last_used_index++;
 610
 611    atomic_mb_set(&used->idx, vq->last_used_index);
 612    vubr_log_write(dev,
 613                   log_guest_addr + offsetof(struct vring_used, idx),
 614                   sizeof(used->idx));
 615
 616    /* Kick the guest if necessary. */
 617    vubr_virtqueue_kick(vq);
 618}
 619
 620static int
 621vubr_process_desc(VubrDev *dev, VubrVirtq *vq)
 622{
 623    struct vring_desc *desc = vq->desc;
 624    struct vring_avail *avail = vq->avail;
 625    struct vring_used *used = vq->used;
 626    uint64_t log_guest_addr = vq->log_guest_addr;
 627
 628    unsigned int size = vq->size;
 629
 630    uint16_t a_index = vq->last_avail_index % size;
 631    uint16_t u_index = vq->last_used_index % size;
 632    uint16_t d_index = avail->ring[a_index];
 633
 634    uint32_t i, len = 0;
 635    size_t buf_size = 4096;
 636    uint8_t buf[4096];
 637
 638    DPRINT("Chunks: ");
 639    i = d_index;
 640    do {
 641        void *chunk_start = (void *)(uintptr_t)gpa_to_va(dev, desc[i].addr);
 642        uint32_t chunk_len = desc[i].len;
 643
 644        assert(!(desc[i].flags & VRING_DESC_F_WRITE));
 645
 646        if (len + chunk_len < buf_size) {
 647            memcpy(buf + len, chunk_start, chunk_len);
 648            DPRINT("%d ", chunk_len);
 649        } else {
 650            fprintf(stderr, "Error: too long packet. Dropping...\n");
 651            break;
 652        }
 653
 654        len += chunk_len;
 655
 656        if (!(desc[i].flags & VRING_DESC_F_NEXT)) {
 657            break;
 658        }
 659
 660        i = desc[i].next;
 661    } while (1);
 662    DPRINT("\n");
 663
 664    if (!len) {
 665        return -1;
 666    }
 667
 668    /* Add descriptor to the used ring. */
 669    used->ring[u_index].id = d_index;
 670    used->ring[u_index].len = len;
 671    vubr_log_write(dev,
 672                   log_guest_addr + offsetof(struct vring_used, ring[u_index]),
 673                   sizeof(used->ring[u_index]));
 674
 675    vubr_consume_raw_packet(dev, buf, len);
 676
 677    return 0;
 678}
 679
 680static void
 681vubr_process_avail(VubrDev *dev, VubrVirtq *vq)
 682{
 683    struct vring_avail *avail = vq->avail;
 684    struct vring_used *used = vq->used;
 685    uint64_t log_guest_addr = vq->log_guest_addr;
 686
 687    while (vq->last_avail_index != atomic_mb_read(&avail->idx)) {
 688        vubr_process_desc(dev, vq);
 689        vq->last_avail_index++;
 690        vq->last_used_index++;
 691    }
 692
 693    atomic_mb_set(&used->idx, vq->last_used_index);
 694    vubr_log_write(dev,
 695                   log_guest_addr + offsetof(struct vring_used, idx),
 696                   sizeof(used->idx));
 697}
 698
 699static void
 700vubr_backend_recv_cb(int sock, void *ctx)
 701{
 702    VubrDev *dev = (VubrDev *) ctx;
 703    VubrVirtq *rx_vq = &dev->vq[0];
 704    uint8_t buf[4096];
 705    struct virtio_net_hdr_v1 *hdr = (struct virtio_net_hdr_v1 *)buf;
 706    int hdrlen = dev->hdrlen;
 707    int buflen = sizeof(buf);
 708    int len;
 709
 710    if (!dev->ready) {
 711        return;
 712    }
 713
 714    DPRINT("\n\n   ***   IN UDP RECEIVE CALLBACK    ***\n\n");
 715    DPRINT("    hdrlen = %d\n", hdrlen);
 716
 717    uint16_t avail_index = atomic_mb_read(&rx_vq->avail->idx);
 718
 719    /* If there is no available descriptors, just do nothing.
 720     * The buffer will be handled by next arrived UDP packet,
 721     * or next kick on receive virtq. */
 722    if (rx_vq->last_avail_index == avail_index) {
 723        DPRINT("Got UDP packet, but no available descriptors on RX virtq.\n");
 724        return;
 725    }
 726
 727    memset(buf, 0, hdrlen);
 728    /* TODO: support mergeable buffers. */
 729    if (hdrlen == 12)
 730        hdr->num_buffers = 1;
 731    len = vubr_backend_udp_recvbuf(dev, buf + hdrlen, buflen - hdrlen);
 732
 733    vubr_post_buffer(dev, rx_vq, buf, len + hdrlen);
 734}
 735
 736static void
 737vubr_kick_cb(int sock, void *ctx)
 738{
 739    VubrDev *dev = (VubrDev *) ctx;
 740    eventfd_t kick_data;
 741    ssize_t rc;
 742
 743    rc = eventfd_read(sock, &kick_data);
 744    if (rc == -1) {
 745        vubr_die("eventfd_read()");
 746    } else {
 747        DPRINT("Got kick_data: %016"PRIx64"\n", kick_data);
 748        vubr_process_avail(dev, &dev->vq[1]);
 749    }
 750}
 751
 752static int
 753vubr_none_exec(VubrDev *dev, VhostUserMsg *vmsg)
 754{
 755    DPRINT("Function %s() not implemented yet.\n", __func__);
 756    return 0;
 757}
 758
 759static int
 760vubr_get_features_exec(VubrDev *dev, VhostUserMsg *vmsg)
 761{
 762    vmsg->payload.u64 =
 763            ((1ULL << VIRTIO_NET_F_MRG_RXBUF) |
 764             (1ULL << VHOST_F_LOG_ALL) |
 765             (1ULL << VIRTIO_NET_F_GUEST_ANNOUNCE) |
 766             (1ULL << VHOST_USER_F_PROTOCOL_FEATURES));
 767
 768    vmsg->size = sizeof(vmsg->payload.u64);
 769
 770    DPRINT("Sending back to guest u64: 0x%016"PRIx64"\n", vmsg->payload.u64);
 771
 772    /* Reply */
 773    return 1;
 774}
 775
 776static int
 777vubr_set_features_exec(VubrDev *dev, VhostUserMsg *vmsg)
 778{
 779    DPRINT("u64: 0x%016"PRIx64"\n", vmsg->payload.u64);
 780
 781    dev->features = vmsg->payload.u64;
 782    if ((dev->features & (1ULL << VIRTIO_F_VERSION_1)) ||
 783        (dev->features & (1ULL << VIRTIO_NET_F_MRG_RXBUF))) {
 784        dev->hdrlen = 12;
 785    } else {
 786        dev->hdrlen = 10;
 787    }
 788
 789    return 0;
 790}
 791
 792static int
 793vubr_set_owner_exec(VubrDev *dev, VhostUserMsg *vmsg)
 794{
 795    return 0;
 796}
 797
 798static void
 799vubr_close_log(VubrDev *dev)
 800{
 801    if (dev->log_table) {
 802        if (munmap(dev->log_table, dev->log_size) != 0) {
 803            vubr_die("munmap()");
 804        }
 805
 806        dev->log_table = 0;
 807    }
 808    if (dev->log_call_fd != -1) {
 809        close(dev->log_call_fd);
 810        dev->log_call_fd = -1;
 811    }
 812}
 813
 814static int
 815vubr_reset_device_exec(VubrDev *dev, VhostUserMsg *vmsg)
 816{
 817    vubr_close_log(dev);
 818    dev->ready = 0;
 819    dev->features = 0;
 820    return 0;
 821}
 822
 823static int
 824vubr_set_mem_table_exec(VubrDev *dev, VhostUserMsg *vmsg)
 825{
 826    int i;
 827    VhostUserMemory *memory = &vmsg->payload.memory;
 828    dev->nregions = memory->nregions;
 829
 830    DPRINT("Nregions: %d\n", memory->nregions);
 831    for (i = 0; i < dev->nregions; i++) {
 832        void *mmap_addr;
 833        VhostUserMemoryRegion *msg_region = &memory->regions[i];
 834        VubrDevRegion *dev_region = &dev->regions[i];
 835
 836        DPRINT("Region %d\n", i);
 837        DPRINT("    guest_phys_addr: 0x%016"PRIx64"\n",
 838               msg_region->guest_phys_addr);
 839        DPRINT("    memory_size:     0x%016"PRIx64"\n",
 840               msg_region->memory_size);
 841        DPRINT("    userspace_addr   0x%016"PRIx64"\n",
 842               msg_region->userspace_addr);
 843        DPRINT("    mmap_offset      0x%016"PRIx64"\n",
 844               msg_region->mmap_offset);
 845
 846        dev_region->gpa = msg_region->guest_phys_addr;
 847        dev_region->size = msg_region->memory_size;
 848        dev_region->qva = msg_region->userspace_addr;
 849        dev_region->mmap_offset = msg_region->mmap_offset;
 850
 851        /* We don't use offset argument of mmap() since the
 852         * mapped address has to be page aligned, and we use huge
 853         * pages.  */
 854        mmap_addr = mmap(0, dev_region->size + dev_region->mmap_offset,
 855                         PROT_READ | PROT_WRITE, MAP_SHARED,
 856                         vmsg->fds[i], 0);
 857
 858        if (mmap_addr == MAP_FAILED) {
 859            vubr_die("mmap");
 860        }
 861        dev_region->mmap_addr = (uint64_t)(uintptr_t)mmap_addr;
 862        DPRINT("    mmap_addr:       0x%016"PRIx64"\n", dev_region->mmap_addr);
 863
 864        close(vmsg->fds[i]);
 865    }
 866
 867    return 0;
 868}
 869
 870static int
 871vubr_set_log_base_exec(VubrDev *dev, VhostUserMsg *vmsg)
 872{
 873    int fd;
 874    uint64_t log_mmap_size, log_mmap_offset;
 875    void *rc;
 876
 877    assert(vmsg->fd_num == 1);
 878    fd = vmsg->fds[0];
 879
 880    assert(vmsg->size == sizeof(vmsg->payload.log));
 881    log_mmap_offset = vmsg->payload.log.mmap_offset;
 882    log_mmap_size = vmsg->payload.log.mmap_size;
 883    DPRINT("Log mmap_offset: %"PRId64"\n", log_mmap_offset);
 884    DPRINT("Log mmap_size:   %"PRId64"\n", log_mmap_size);
 885
 886    rc = mmap(0, log_mmap_size, PROT_READ | PROT_WRITE, MAP_SHARED, fd,
 887              log_mmap_offset);
 888    if (rc == MAP_FAILED) {
 889        vubr_die("mmap");
 890    }
 891    dev->log_table = rc;
 892    dev->log_size = log_mmap_size;
 893
 894    vmsg->size = sizeof(vmsg->payload.u64);
 895    /* Reply */
 896    return 1;
 897}
 898
 899static int
 900vubr_set_log_fd_exec(VubrDev *dev, VhostUserMsg *vmsg)
 901{
 902    assert(vmsg->fd_num == 1);
 903    dev->log_call_fd = vmsg->fds[0];
 904    DPRINT("Got log_call_fd: %d\n", vmsg->fds[0]);
 905    return 0;
 906}
 907
 908static int
 909vubr_set_vring_num_exec(VubrDev *dev, VhostUserMsg *vmsg)
 910{
 911    unsigned int index = vmsg->payload.state.index;
 912    unsigned int num = vmsg->payload.state.num;
 913
 914    DPRINT("State.index: %d\n", index);
 915    DPRINT("State.num:   %d\n", num);
 916    dev->vq[index].size = num;
 917    return 0;
 918}
 919
 920static int
 921vubr_set_vring_addr_exec(VubrDev *dev, VhostUserMsg *vmsg)
 922{
 923    struct vhost_vring_addr *vra = &vmsg->payload.addr;
 924    unsigned int index = vra->index;
 925    VubrVirtq *vq = &dev->vq[index];
 926
 927    DPRINT("vhost_vring_addr:\n");
 928    DPRINT("    index:  %d\n", vra->index);
 929    DPRINT("    flags:  %d\n", vra->flags);
 930    DPRINT("    desc_user_addr:   0x%016llx\n", vra->desc_user_addr);
 931    DPRINT("    used_user_addr:   0x%016llx\n", vra->used_user_addr);
 932    DPRINT("    avail_user_addr:  0x%016llx\n", vra->avail_user_addr);
 933    DPRINT("    log_guest_addr:   0x%016llx\n", vra->log_guest_addr);
 934
 935    vq->desc = (struct vring_desc *)(uintptr_t)qva_to_va(dev, vra->desc_user_addr);
 936    vq->used = (struct vring_used *)(uintptr_t)qva_to_va(dev, vra->used_user_addr);
 937    vq->avail = (struct vring_avail *)(uintptr_t)qva_to_va(dev, vra->avail_user_addr);
 938    vq->log_guest_addr = vra->log_guest_addr;
 939
 940    DPRINT("Setting virtq addresses:\n");
 941    DPRINT("    vring_desc  at %p\n", vq->desc);
 942    DPRINT("    vring_used  at %p\n", vq->used);
 943    DPRINT("    vring_avail at %p\n", vq->avail);
 944
 945    vq->last_used_index = vq->used->idx;
 946
 947    if (vq->last_avail_index != vq->used->idx) {
 948        DPRINT("Last avail index != used index: %d != %d, resuming",
 949               vq->last_avail_index, vq->used->idx);
 950        vq->last_avail_index = vq->used->idx;
 951    }
 952
 953    return 0;
 954}
 955
 956static int
 957vubr_set_vring_base_exec(VubrDev *dev, VhostUserMsg *vmsg)
 958{
 959    unsigned int index = vmsg->payload.state.index;
 960    unsigned int num = vmsg->payload.state.num;
 961
 962    DPRINT("State.index: %d\n", index);
 963    DPRINT("State.num:   %d\n", num);
 964    dev->vq[index].last_avail_index = num;
 965
 966    return 0;
 967}
 968
 969static int
 970vubr_get_vring_base_exec(VubrDev *dev, VhostUserMsg *vmsg)
 971{
 972    unsigned int index = vmsg->payload.state.index;
 973
 974    DPRINT("State.index: %d\n", index);
 975    vmsg->payload.state.num = dev->vq[index].last_avail_index;
 976    vmsg->size = sizeof(vmsg->payload.state);
 977    /* FIXME: this is a work-around for a bug in QEMU enabling
 978     * too early vrings. When protocol features are enabled,
 979     * we have to respect * VHOST_USER_SET_VRING_ENABLE request. */
 980    dev->ready = 0;
 981
 982    if (dev->vq[index].call_fd != -1) {
 983        close(dev->vq[index].call_fd);
 984        dispatcher_remove(&dev->dispatcher, dev->vq[index].call_fd);
 985        dev->vq[index].call_fd = -1;
 986    }
 987    if (dev->vq[index].kick_fd != -1) {
 988        close(dev->vq[index].kick_fd);
 989        dispatcher_remove(&dev->dispatcher, dev->vq[index].kick_fd);
 990        dev->vq[index].kick_fd = -1;
 991    }
 992
 993    /* Reply */
 994    return 1;
 995}
 996
 997static int
 998vubr_set_vring_kick_exec(VubrDev *dev, VhostUserMsg *vmsg)
 999{
1000    uint64_t u64_arg = vmsg->payload.u64;
1001    int index = u64_arg & VHOST_USER_VRING_IDX_MASK;
1002
1003    DPRINT("u64: 0x%016"PRIx64"\n", vmsg->payload.u64);
1004
1005    assert((u64_arg & VHOST_USER_VRING_NOFD_MASK) == 0);
1006    assert(vmsg->fd_num == 1);
1007
1008    if (dev->vq[index].kick_fd != -1) {
1009        close(dev->vq[index].kick_fd);
1010        dispatcher_remove(&dev->dispatcher, dev->vq[index].kick_fd);
1011    }
1012    dev->vq[index].kick_fd = vmsg->fds[0];
1013    DPRINT("Got kick_fd: %d for vq: %d\n", vmsg->fds[0], index);
1014
1015    if (index % 2 == 1) {
1016        /* TX queue. */
1017        dispatcher_add(&dev->dispatcher, dev->vq[index].kick_fd,
1018                       dev, vubr_kick_cb);
1019
1020        DPRINT("Waiting for kicks on fd: %d for vq: %d\n",
1021               dev->vq[index].kick_fd, index);
1022    }
1023    /* We temporarily use this hack to determine that both TX and RX
1024     * queues are set up and ready for processing.
1025     * FIXME: we need to rely in VHOST_USER_SET_VRING_ENABLE and
1026     * actual kicks. */
1027    if (dev->vq[0].kick_fd != -1 &&
1028        dev->vq[1].kick_fd != -1) {
1029        dev->ready = 1;
1030        DPRINT("vhost-user-bridge is ready for processing queues.\n");
1031    }
1032    return 0;
1033
1034}
1035
1036static int
1037vubr_set_vring_call_exec(VubrDev *dev, VhostUserMsg *vmsg)
1038{
1039    uint64_t u64_arg = vmsg->payload.u64;
1040    int index = u64_arg & VHOST_USER_VRING_IDX_MASK;
1041
1042    DPRINT("u64: 0x%016"PRIx64"\n", vmsg->payload.u64);
1043    assert((u64_arg & VHOST_USER_VRING_NOFD_MASK) == 0);
1044    assert(vmsg->fd_num == 1);
1045
1046    if (dev->vq[index].call_fd != -1) {
1047        close(dev->vq[index].call_fd);
1048        dispatcher_remove(&dev->dispatcher, dev->vq[index].call_fd);
1049    }
1050    dev->vq[index].call_fd = vmsg->fds[0];
1051    DPRINT("Got call_fd: %d for vq: %d\n", vmsg->fds[0], index);
1052
1053    return 0;
1054}
1055
1056static int
1057vubr_set_vring_err_exec(VubrDev *dev, VhostUserMsg *vmsg)
1058{
1059    DPRINT("u64: 0x%016"PRIx64"\n", vmsg->payload.u64);
1060    return 0;
1061}
1062
1063static int
1064vubr_get_protocol_features_exec(VubrDev *dev, VhostUserMsg *vmsg)
1065{
1066    vmsg->payload.u64 = 1ULL << VHOST_USER_PROTOCOL_F_LOG_SHMFD;
1067    DPRINT("u64: 0x%016"PRIx64"\n", vmsg->payload.u64);
1068    vmsg->size = sizeof(vmsg->payload.u64);
1069
1070    /* Reply */
1071    return 1;
1072}
1073
1074static int
1075vubr_set_protocol_features_exec(VubrDev *dev, VhostUserMsg *vmsg)
1076{
1077    /* FIXME: unimplented */
1078    DPRINT("u64: 0x%016"PRIx64"\n", vmsg->payload.u64);
1079    return 0;
1080}
1081
1082static int
1083vubr_get_queue_num_exec(VubrDev *dev, VhostUserMsg *vmsg)
1084{
1085    DPRINT("Function %s() not implemented yet.\n", __func__);
1086    return 0;
1087}
1088
1089static int
1090vubr_set_vring_enable_exec(VubrDev *dev, VhostUserMsg *vmsg)
1091{
1092    unsigned int index = vmsg->payload.state.index;
1093    unsigned int enable = vmsg->payload.state.num;
1094
1095    DPRINT("State.index: %d\n", index);
1096    DPRINT("State.enable:   %d\n", enable);
1097    dev->vq[index].enable = enable;
1098    return 0;
1099}
1100
1101static int
1102vubr_send_rarp_exec(VubrDev *dev, VhostUserMsg *vmsg)
1103{
1104    DPRINT("Function %s() not implemented yet.\n", __func__);
1105    return 0;
1106}
1107
1108static int
1109vubr_execute_request(VubrDev *dev, VhostUserMsg *vmsg)
1110{
1111    /* Print out generic part of the request. */
1112    DPRINT(
1113           "==================   Vhost user message from QEMU   ==================\n");
1114    DPRINT("Request: %s (%d)\n", vubr_request_str[vmsg->request],
1115           vmsg->request);
1116    DPRINT("Flags:   0x%x\n", vmsg->flags);
1117    DPRINT("Size:    %d\n", vmsg->size);
1118
1119    if (vmsg->fd_num) {
1120        int i;
1121        DPRINT("Fds:");
1122        for (i = 0; i < vmsg->fd_num; i++) {
1123            DPRINT(" %d", vmsg->fds[i]);
1124        }
1125        DPRINT("\n");
1126    }
1127
1128    switch (vmsg->request) {
1129    case VHOST_USER_NONE:
1130        return vubr_none_exec(dev, vmsg);
1131    case VHOST_USER_GET_FEATURES:
1132        return vubr_get_features_exec(dev, vmsg);
1133    case VHOST_USER_SET_FEATURES:
1134        return vubr_set_features_exec(dev, vmsg);
1135    case VHOST_USER_SET_OWNER:
1136        return vubr_set_owner_exec(dev, vmsg);
1137    case VHOST_USER_RESET_OWNER:
1138        return vubr_reset_device_exec(dev, vmsg);
1139    case VHOST_USER_SET_MEM_TABLE:
1140        return vubr_set_mem_table_exec(dev, vmsg);
1141    case VHOST_USER_SET_LOG_BASE:
1142        return vubr_set_log_base_exec(dev, vmsg);
1143    case VHOST_USER_SET_LOG_FD:
1144        return vubr_set_log_fd_exec(dev, vmsg);
1145    case VHOST_USER_SET_VRING_NUM:
1146        return vubr_set_vring_num_exec(dev, vmsg);
1147    case VHOST_USER_SET_VRING_ADDR:
1148        return vubr_set_vring_addr_exec(dev, vmsg);
1149    case VHOST_USER_SET_VRING_BASE:
1150        return vubr_set_vring_base_exec(dev, vmsg);
1151    case VHOST_USER_GET_VRING_BASE:
1152        return vubr_get_vring_base_exec(dev, vmsg);
1153    case VHOST_USER_SET_VRING_KICK:
1154        return vubr_set_vring_kick_exec(dev, vmsg);
1155    case VHOST_USER_SET_VRING_CALL:
1156        return vubr_set_vring_call_exec(dev, vmsg);
1157    case VHOST_USER_SET_VRING_ERR:
1158        return vubr_set_vring_err_exec(dev, vmsg);
1159    case VHOST_USER_GET_PROTOCOL_FEATURES:
1160        return vubr_get_protocol_features_exec(dev, vmsg);
1161    case VHOST_USER_SET_PROTOCOL_FEATURES:
1162        return vubr_set_protocol_features_exec(dev, vmsg);
1163    case VHOST_USER_GET_QUEUE_NUM:
1164        return vubr_get_queue_num_exec(dev, vmsg);
1165    case VHOST_USER_SET_VRING_ENABLE:
1166        return vubr_set_vring_enable_exec(dev, vmsg);
1167    case VHOST_USER_SEND_RARP:
1168        return vubr_send_rarp_exec(dev, vmsg);
1169
1170    case VHOST_USER_MAX:
1171        assert(vmsg->request != VHOST_USER_MAX);
1172    }
1173    return 0;
1174}
1175
1176static void
1177vubr_receive_cb(int sock, void *ctx)
1178{
1179    VubrDev *dev = (VubrDev *) ctx;
1180    VhostUserMsg vmsg;
1181    int reply_requested;
1182
1183    vubr_message_read(sock, &vmsg);
1184    reply_requested = vubr_execute_request(dev, &vmsg);
1185    if (reply_requested) {
1186        /* Set the version in the flags when sending the reply */
1187        vmsg.flags &= ~VHOST_USER_VERSION_MASK;
1188        vmsg.flags |= VHOST_USER_VERSION;
1189        vmsg.flags |= VHOST_USER_REPLY_MASK;
1190        vubr_message_write(sock, &vmsg);
1191    }
1192}
1193
1194static void
1195vubr_accept_cb(int sock, void *ctx)
1196{
1197    VubrDev *dev = (VubrDev *)ctx;
1198    int conn_fd;
1199    struct sockaddr_un un;
1200    socklen_t len = sizeof(un);
1201
1202    conn_fd = accept(sock, (struct sockaddr *) &un, &len);
1203    if (conn_fd == -1) {
1204        vubr_die("accept()");
1205    }
1206    DPRINT("Got connection from remote peer on sock %d\n", conn_fd);
1207    dispatcher_add(&dev->dispatcher, conn_fd, ctx, vubr_receive_cb);
1208}
1209
1210static VubrDev *
1211vubr_new(const char *path, bool client)
1212{
1213    VubrDev *dev = (VubrDev *) calloc(1, sizeof(VubrDev));
1214    dev->nregions = 0;
1215    int i;
1216    struct sockaddr_un un;
1217    CallbackFunc cb;
1218    size_t len;
1219
1220    for (i = 0; i < MAX_NR_VIRTQUEUE; i++) {
1221        dev->vq[i] = (VubrVirtq) {
1222            .call_fd = -1, .kick_fd = -1,
1223            .size = 0,
1224            .last_avail_index = 0, .last_used_index = 0,
1225            .desc = 0, .avail = 0, .used = 0,
1226            .enable = 0,
1227        };
1228    }
1229
1230    /* Init log */
1231    dev->log_call_fd = -1;
1232    dev->log_size = 0;
1233    dev->log_table = 0;
1234    dev->ready = 0;
1235    dev->features = 0;
1236
1237    /* Get a UNIX socket. */
1238    dev->sock = socket(AF_UNIX, SOCK_STREAM, 0);
1239    if (dev->sock == -1) {
1240        vubr_die("socket");
1241    }
1242
1243    un.sun_family = AF_UNIX;
1244    strcpy(un.sun_path, path);
1245    len = sizeof(un.sun_family) + strlen(path);
1246
1247    if (!client) {
1248        unlink(path);
1249
1250        if (bind(dev->sock, (struct sockaddr *) &un, len) == -1) {
1251            vubr_die("bind");
1252        }
1253
1254        if (listen(dev->sock, 1) == -1) {
1255            vubr_die("listen");
1256        }
1257        cb = vubr_accept_cb;
1258
1259        DPRINT("Waiting for connections on UNIX socket %s ...\n", path);
1260    } else {
1261        if (connect(dev->sock, (struct sockaddr *)&un, len) == -1) {
1262            vubr_die("connect");
1263        }
1264        cb = vubr_receive_cb;
1265    }
1266
1267    dispatcher_init(&dev->dispatcher);
1268    dispatcher_add(&dev->dispatcher, dev->sock, (void *)dev, cb);
1269
1270    return dev;
1271}
1272
1273static void
1274vubr_set_host(struct sockaddr_in *saddr, const char *host)
1275{
1276    if (isdigit(host[0])) {
1277        if (!inet_aton(host, &saddr->sin_addr)) {
1278            fprintf(stderr, "inet_aton() failed.\n");
1279            exit(1);
1280        }
1281    } else {
1282        struct hostent *he = gethostbyname(host);
1283
1284        if (!he) {
1285            fprintf(stderr, "gethostbyname() failed.\n");
1286            exit(1);
1287        }
1288        saddr->sin_addr = *(struct in_addr *)he->h_addr;
1289    }
1290}
1291
1292static void
1293vubr_backend_udp_setup(VubrDev *dev,
1294                       const char *local_host,
1295                       const char *local_port,
1296                       const char *remote_host,
1297                       const char *remote_port)
1298{
1299    int sock;
1300    const char *r;
1301
1302    int lport, rport;
1303
1304    lport = strtol(local_port, (char **)&r, 0);
1305    if (r == local_port) {
1306        fprintf(stderr, "lport parsing failed.\n");
1307        exit(1);
1308    }
1309
1310    rport = strtol(remote_port, (char **)&r, 0);
1311    if (r == remote_port) {
1312        fprintf(stderr, "rport parsing failed.\n");
1313        exit(1);
1314    }
1315
1316    struct sockaddr_in si_local = {
1317        .sin_family = AF_INET,
1318        .sin_port = htons(lport),
1319    };
1320
1321    vubr_set_host(&si_local, local_host);
1322
1323    /* setup destination for sends */
1324    dev->backend_udp_dest = (struct sockaddr_in) {
1325        .sin_family = AF_INET,
1326        .sin_port = htons(rport),
1327    };
1328    vubr_set_host(&dev->backend_udp_dest, remote_host);
1329
1330    sock = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
1331    if (sock == -1) {
1332        vubr_die("socket");
1333    }
1334
1335    if (bind(sock, (struct sockaddr *)&si_local, sizeof(si_local)) == -1) {
1336        vubr_die("bind");
1337    }
1338
1339    dev->backend_udp_sock = sock;
1340    dispatcher_add(&dev->dispatcher, sock, dev, vubr_backend_recv_cb);
1341    DPRINT("Waiting for data from udp backend on %s:%d...\n",
1342           local_host, lport);
1343}
1344
1345static void
1346vubr_run(VubrDev *dev)
1347{
1348    while (1) {
1349        /* timeout 200ms */
1350        dispatcher_wait(&dev->dispatcher, 200000);
1351        /* Here one can try polling strategy. */
1352    }
1353}
1354
1355static int
1356vubr_parse_host_port(const char **host, const char **port, const char *buf)
1357{
1358    char *p = strchr(buf, ':');
1359
1360    if (!p) {
1361        return -1;
1362    }
1363    *p = '\0';
1364    *host = strdup(buf);
1365    *port = strdup(p + 1);
1366    return 0;
1367}
1368
1369#define DEFAULT_UD_SOCKET "/tmp/vubr.sock"
1370#define DEFAULT_LHOST "127.0.0.1"
1371#define DEFAULT_LPORT "4444"
1372#define DEFAULT_RHOST "127.0.0.1"
1373#define DEFAULT_RPORT "5555"
1374
1375static const char *ud_socket_path = DEFAULT_UD_SOCKET;
1376static const char *lhost = DEFAULT_LHOST;
1377static const char *lport = DEFAULT_LPORT;
1378static const char *rhost = DEFAULT_RHOST;
1379static const char *rport = DEFAULT_RPORT;
1380
1381int
1382main(int argc, char *argv[])
1383{
1384    VubrDev *dev;
1385    int opt;
1386    bool client = false;
1387
1388    while ((opt = getopt(argc, argv, "l:r:u:c")) != -1) {
1389
1390        switch (opt) {
1391        case 'l':
1392            if (vubr_parse_host_port(&lhost, &lport, optarg) < 0) {
1393                goto out;
1394            }
1395            break;
1396        case 'r':
1397            if (vubr_parse_host_port(&rhost, &rport, optarg) < 0) {
1398                goto out;
1399            }
1400            break;
1401        case 'u':
1402            ud_socket_path = strdup(optarg);
1403            break;
1404        case 'c':
1405            client = true;
1406            break;
1407        default:
1408            goto out;
1409        }
1410    }
1411
1412    DPRINT("ud socket: %s (%s)\n", ud_socket_path,
1413           client ? "client" : "server");
1414    DPRINT("local:     %s:%s\n", lhost, lport);
1415    DPRINT("remote:    %s:%s\n", rhost, rport);
1416
1417    dev = vubr_new(ud_socket_path, client);
1418    if (!dev) {
1419        return 1;
1420    }
1421
1422    vubr_backend_udp_setup(dev, lhost, lport, rhost, rport);
1423    vubr_run(dev);
1424    return 0;
1425
1426out:
1427    fprintf(stderr, "Usage: %s ", argv[0]);
1428    fprintf(stderr, "[-c] [-u ud_socket_path] [-l lhost:lport] [-r rhost:rport]\n");
1429    fprintf(stderr, "\t-u path to unix doman socket. default: %s\n",
1430            DEFAULT_UD_SOCKET);
1431    fprintf(stderr, "\t-l local host and port. default: %s:%s\n",
1432            DEFAULT_LHOST, DEFAULT_LPORT);
1433    fprintf(stderr, "\t-r remote host and port. default: %s:%s\n",
1434            DEFAULT_RHOST, DEFAULT_RPORT);
1435    fprintf(stderr, "\t-c client mode\n");
1436
1437    return 1;
1438}
1439