1 /* Copyright (c) 2008 The Board of Trustees of The Leland Stanford
4 * We are making the OpenFlow specification and associated documentation
5 * (Software) available for public use and benefit with the expectation
6 * that others will use, modify and enhance the Software and contribute
7 * those enhancements back to the community. However, since we would
8 * like to make the Software available for broadest use, with as few
9 * restrictions as possible permission is hereby granted, free of
10 * charge, to any person obtaining a copy of this Software to deal in
11 * the Software under the copyrights without restriction, including
12 * without limitation the rights to use, copy, modify, merge, publish,
13 * distribute, sublicense, and/or sell copies of the Software, and to
14 * permit persons to whom the Software is furnished to do so, subject to
15 * the following conditions:
17 * The above copyright notice and this permission notice shall be
18 * included in all copies or substantial portions of the Software.
20 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
21 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
22 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
23 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
24 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
25 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
26 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
29 * The name and trademarks of copyright holder(s) may NOT be used in
30 * advertising or publicity pertaining to the Software or any
31 * derivatives without specific, written prior permission.
38 #include <arpa/inet.h>
40 #include <linux/types.h>
41 #include <linux/ethtool.h>
42 #include <linux/sockios.h>
43 #include <sys/types.h>
44 #include <sys/ioctl.h>
45 #include <sys/socket.h>
46 #include <netpacket/packet.h>
47 #include <net/ethernet.h>
49 #include <net/if_arp.h>
50 #include <net/if_packet.h>
51 #include <netinet/in.h>
57 #include "fatal-signal.h"
61 #include "poll-loop.h"
62 #include "socket-util.h"
64 #define THIS_MODULE VLM_netdev
71 uint8_t etheraddr[ETH_ADDR_LEN];
80 static struct list netdev_list = LIST_INITIALIZER(&netdev_list);
82 /* An AF_INET socket (used for ioctl operations). */
83 static int af_inet_sock = -1;
85 static void init_netdev(void);
86 static int restore_flags(struct netdev *netdev);
87 static int get_flags(const struct netdev *, int *flagsp);
88 static int set_flags(struct netdev *, int flags);
90 /* Obtains the IPv4 address for 'name' into 'in4'. Returns true if
93 get_ipv4_address(const char *name, struct in_addr *in4)
97 strncpy(ifr.ifr_name, name, sizeof ifr.ifr_name);
98 ifr.ifr_addr.sa_family = AF_INET;
99 if (ioctl(af_inet_sock, SIOCGIFADDR, &ifr) == 0) {
100 struct sockaddr_in *sin = (struct sockaddr_in *) &ifr.ifr_addr;
101 *in4 = sin->sin_addr;
103 in4->s_addr = INADDR_ANY;
109 /* Obtains the IPv6 address for 'name' into 'in6'. */
111 get_ipv6_address(const char *name, struct in6_addr *in6)
116 file = fopen("/proc/net/if_inet6", "r");
118 /* This most likely indicates that the host doesn't have IPv6 support,
119 * so it's not really a failure condition.*/
124 while (fgets(line, sizeof line, file)) {
125 uint8_t *s6 = in6->s6_addr;
129 if (sscanf(line, " "X8 X8 X8 X8 X8 X8 X8 X8 X8 X8 X8 X8 X8 X8 X8 X8
130 "%*x %*x %*x %*x %16s\n",
131 &s6[0], &s6[1], &s6[2], &s6[3],
132 &s6[4], &s6[5], &s6[6], &s6[7],
133 &s6[8], &s6[9], &s6[10], &s6[11],
134 &s6[12], &s6[13], &s6[14], &s6[15],
136 && !strcmp(name, ifname))
147 do_ethtool(struct netdev *netdev)
150 struct ethtool_cmd ecmd;
153 netdev->features = 0;
155 memset(&ifr, 0, sizeof ifr);
156 strncpy(ifr.ifr_name, netdev->name, sizeof ifr.ifr_name);
157 ifr.ifr_data = (caddr_t) &ecmd;
159 memset(&ecmd, 0, sizeof ecmd);
160 ecmd.cmd = ETHTOOL_GSET;
161 if (ioctl(netdev->fd, SIOCETHTOOL, &ifr) == 0) {
162 if (ecmd.supported & SUPPORTED_10baseT_Half) {
163 netdev->features |= OFPPF_10MB_HD;
165 if (ecmd.supported & SUPPORTED_10baseT_Full) {
166 netdev->features |= OFPPF_10MB_FD;
168 if (ecmd.supported & SUPPORTED_100baseT_Half) {
169 netdev->features |= OFPPF_100MB_HD;
171 if (ecmd.supported & SUPPORTED_100baseT_Full) {
172 netdev->features |= OFPPF_100MB_FD;
174 if (ecmd.supported & SUPPORTED_1000baseT_Half) {
175 netdev->features |= OFPPF_1GB_HD;
177 if (ecmd.supported & SUPPORTED_1000baseT_Full) {
178 netdev->features |= OFPPF_1GB_FD;
180 /* 10Gbps half-duplex doesn't exist... */
181 if (ecmd.supported & SUPPORTED_10000baseT_Full) {
182 netdev->features |= OFPPF_10GB_FD;
185 switch (ecmd.speed) {
195 netdev->speed = 1000;
199 netdev->speed = 2500;
203 netdev->speed = 10000;
207 VLOG_DBG("ioctl(SIOCETHTOOL) failed: %s", strerror(errno));
211 /* Opens the network device named 'name' (e.g. "eth0") and returns zero if
212 * successful, otherwise a positive errno value. On success, sets '*netdev'
213 * to the new network device, otherwise to null.
215 * 'ethertype' may be a 16-bit Ethernet protocol value in host byte order to
216 * capture frames of that type received on the device. It may also be one of
217 * the 'enum netdev_pseudo_ethertype' values to receive frames in one of those
220 netdev_open(const char *name, int ethertype, struct netdev **netdev_)
225 unsigned int ifindex;
226 uint8_t etheraddr[ETH_ADDR_LEN];
231 struct netdev *netdev;
236 /* Create raw socket.
238 * We have to use SOCK_PACKET, despite its deprecation, because only
239 * SOCK_PACKET lets us set the hardware source address of outgoing
241 fd = socket(PF_PACKET, SOCK_PACKET,
242 htons(ethertype == NETDEV_ETH_TYPE_NONE ? 0
243 : ethertype == NETDEV_ETH_TYPE_ANY ? ETH_P_ALL
244 : ethertype == NETDEV_ETH_TYPE_802_2 ? ETH_P_802_2
250 /* Bind to specific ethernet device. */
251 memset(&sa, 0, sizeof sa);
252 sa.sa_family = AF_UNSPEC;
253 strncpy((char *) sa.sa_data, name, sizeof sa.sa_data);
254 if (bind(fd, &sa, sizeof sa) < 0) {
255 VLOG_ERR("bind to %s failed: %s", name, strerror(errno));
259 if (ethertype != NETDEV_ETH_TYPE_NONE) {
260 /* Between the socket() and bind() calls above, the socket receives all
261 * packets of the requested type on all system interfaces. We do not
262 * want to receive that data, but there is no way to avoid it. So we
263 * must now drain out the receive queue. */
264 error = drain_rcvbuf(fd);
270 /* Get ethernet device index. */
271 strncpy(ifr.ifr_name, name, sizeof ifr.ifr_name);
272 if (ioctl(fd, SIOCGIFINDEX, &ifr) < 0) {
273 VLOG_ERR("ioctl(SIOCGIFINDEX) on %s device failed: %s",
274 name, strerror(errno));
277 ifindex = ifr.ifr_ifindex;
279 /* Get MAC address. */
280 if (ioctl(fd, SIOCGIFHWADDR, &ifr) < 0) {
281 VLOG_ERR("ioctl(SIOCGIFHWADDR) on %s device failed: %s",
282 name, strerror(errno));
285 if (ifr.ifr_hwaddr.sa_family != AF_UNSPEC
286 && ifr.ifr_hwaddr.sa_family != ARPHRD_ETHER) {
287 VLOG_WARN("%s device has unknown hardware address family %d",
288 name, (int) ifr.ifr_hwaddr.sa_family);
290 memcpy(etheraddr, ifr.ifr_hwaddr.sa_data, sizeof etheraddr);
293 if (ioctl(fd, SIOCGIFMTU, &ifr) < 0) {
294 VLOG_ERR("ioctl(SIOCGIFMTU) on %s device failed: %s",
295 name, strerror(errno));
300 if (!get_ipv4_address(name, &in4)) {
303 get_ipv6_address(name, &in6);
305 /* Allocate network device. */
306 netdev = xmalloc(sizeof *netdev);
307 netdev->name = xstrdup(name);
309 memcpy(netdev->etheraddr, etheraddr, sizeof etheraddr);
314 /* Get speed, features. */
317 /* Save flags to restore at close or exit. */
318 error = get_flags(netdev, &netdev->save_flags);
322 fatal_signal_block();
323 list_push_back(&netdev_list, &netdev->node);
324 fatal_signal_unblock();
337 /* Closes and destroys 'netdev'. */
339 netdev_close(struct netdev *netdev)
342 /* Bring down interface and drop promiscuous mode, if we brought up
343 * the interface or enabled promiscuous mode. */
345 fatal_signal_block();
346 error = restore_flags(netdev);
347 list_remove(&netdev->node);
348 fatal_signal_unblock();
350 VLOG_WARN("failed to restore network device flags on %s: %s",
351 netdev->name, strerror(error));
361 /* Pads 'buffer' out with zero-bytes to the minimum valid length of an
362 * Ethernet packet, if necessary. */
364 pad_to_minimum_length(struct buffer *buffer)
366 if (buffer->size < ETH_TOTAL_MIN) {
367 size_t shortage = ETH_TOTAL_MIN - buffer->size;
368 memset(buffer_put_uninit(buffer, shortage), 0, shortage);
372 /* Attempts to receive a packet from 'netdev' into 'buffer', which the caller
373 * must have initialized with sufficient room for the packet. The space
374 * required to receive any packet is ETH_HEADER_LEN bytes, plus VLAN_HEADER_LEN
375 * bytes, plus the device's MTU (which may be retrieved via netdev_get_mtu()).
376 * (Some devices do not allow for a VLAN header, in which case VLAN_HEADER_LEN
377 * need not be included.)
379 * If a packet is successfully retrieved, returns 0. In this case 'buffer' is
380 * guaranteed to contain at least ETH_TOTAL_MIN bytes. Otherwise, returns a
381 * positive errno value. Returns EAGAIN immediately if no packet is ready to
385 netdev_recv(struct netdev *netdev, struct buffer *buffer)
389 assert(buffer->size == 0);
390 assert(buffer_tailroom(buffer) >= ETH_TOTAL_MIN);
392 n_bytes = recv(netdev->fd,
393 buffer_tail(buffer), buffer_tailroom(buffer),
395 } while (n_bytes < 0 && errno == EINTR);
397 if (errno != EAGAIN) {
398 VLOG_WARN("error receiving Ethernet packet on %s: %s",
399 strerror(errno), netdev->name);
403 buffer->size += n_bytes;
405 /* When the kernel internally sends out an Ethernet frame on an
406 * interface, it gives us a copy *before* padding the frame to the
407 * minimum length. Thus, when it sends out something like an ARP
408 * request, we see a too-short frame. So pad it out to the minimum
410 pad_to_minimum_length(buffer);
415 /* Registers with the poll loop to wake up from the next call to poll_block()
416 * when a packet is ready to be received with netdev_recv() on 'netdev'. */
418 netdev_recv_wait(struct netdev *netdev)
420 poll_fd_wait(netdev->fd, POLLIN);
423 /* Discards all packets waiting to be received from 'netdev'. */
425 netdev_drain(struct netdev *netdev)
427 drain_rcvbuf(netdev->fd);
430 /* Sends 'buffer' on 'netdev'. Returns 0 if successful, otherwise a positive
431 * errno value. Returns EAGAIN without blocking if the packet cannot be queued
432 * immediately. Returns EMSGSIZE if a partial packet was transmitted or if
433 * the packet is too big or too small to transmit on the device.
435 * The caller retains ownership of 'buffer' in all cases.
437 * The kernel maintains a packet transmission queue, so the caller is not
438 * expected to do additional queuing of packets. */
440 netdev_send(struct netdev *netdev, const struct buffer *buffer)
443 const struct eth_header *eh;
444 struct sockaddr_pkt spkt;
446 /* Pull out the Ethernet header. */
447 if (buffer->size < ETH_HEADER_LEN) {
448 VLOG_WARN("cannot send %zu-byte frame on %s",
449 buffer->size, netdev->name);
452 eh = buffer_at_assert(buffer, 0, sizeof *eh);
454 /* Construct packet sockaddr, which SOCK_PACKET requires. */
455 spkt.spkt_family = AF_PACKET;
456 strncpy((char *) spkt.spkt_device, netdev->name, sizeof spkt.spkt_device);
457 spkt.spkt_protocol = eh->eth_type;
460 n_bytes = sendto(netdev->fd, buffer->data, buffer->size, 0,
461 (const struct sockaddr *) &spkt, sizeof spkt);
462 } while (n_bytes < 0 && errno == EINTR);
465 /* The Linux AF_PACKET implementation never blocks waiting for room
466 * for packets, instead returning ENOBUFS. Translate this into EAGAIN
468 if (errno == ENOBUFS) {
470 } else if (errno != EAGAIN) {
471 VLOG_WARN("error sending Ethernet packet on %s: %s",
472 netdev->name, strerror(errno));
475 } else if (n_bytes != buffer->size) {
476 VLOG_WARN("send partial Ethernet packet (%d bytes of %zu) on %s",
477 (int) n_bytes, buffer->size, netdev->name);
484 /* Registers with the poll loop to wake up from the next call to poll_block()
485 * when the packet transmission queue has sufficient room to transmit a packet
486 * with netdev_send().
488 * The kernel maintains a packet transmission queue, so the client is not
489 * expected to do additional queuing of packets. Thus, this function is
490 * unlikely to ever be used. It is included for completeness. */
492 netdev_send_wait(struct netdev *netdev)
494 poll_fd_wait(netdev->fd, POLLOUT);
497 /* Returns a pointer to 'netdev''s MAC address. The caller must not modify or
498 * free the returned buffer. */
500 netdev_get_etheraddr(const struct netdev *netdev)
502 return netdev->etheraddr;
505 /* Returns the name of the network device that 'netdev' represents,
506 * e.g. "eth0". The caller must not modify or free the returned string. */
508 netdev_get_name(const struct netdev *netdev)
513 /* Returns the maximum size of transmitted (and received) packets on 'netdev',
514 * in bytes, not including the hardware header; thus, this is typically 1500
515 * bytes for Ethernet devices. */
517 netdev_get_mtu(const struct netdev *netdev)
522 /* Returns the current speed of the network device that 'netdev' represents, in
523 * megabits per second, or 0 if the speed is unknown. */
525 netdev_get_speed(const struct netdev *netdev)
527 return netdev->speed;
530 /* Returns the features supported by 'netdev', as a bitmap of bits from enum
531 * ofp_phy_port, in host byte order. */
533 netdev_get_features(const struct netdev *netdev)
535 return netdev->features;
538 /* If 'netdev' has an assigned IPv4 address, sets '*in4' to that address and
539 * returns true. Otherwise, returns false. */
541 netdev_get_in4(const struct netdev *netdev, struct in_addr *in4)
544 return in4->s_addr != INADDR_ANY;
547 /* If 'netdev' has an assigned IPv6 address, sets '*in6' to that address and
548 * returns true. Otherwise, returns false. */
550 netdev_get_in6(const struct netdev *netdev, struct in6_addr *in6)
553 return memcmp(in6, &in6addr_any, sizeof *in6) != 0;
556 /* Obtains the current flags for 'netdev' and stores them into '*flagsp'.
557 * Returns 0 if successful, otherwise a positive errno value. */
559 netdev_get_flags(const struct netdev *netdev, enum netdev_flags *flagsp)
563 error = get_flags(netdev, &flags);
569 if (flags & IFF_UP) {
570 *flagsp |= NETDEV_UP;
572 if (flags & IFF_PROMISC) {
573 *flagsp |= NETDEV_PROMISC;
578 /* Sets the flags for 'netdev' to 'nd_flags'.
579 * Returns 0 if successful, otherwise a positive errno value. */
581 netdev_set_flags(struct netdev *netdev, enum netdev_flags nd_flags)
583 int old_flags, new_flags;
586 error = get_flags(netdev, &old_flags);
591 new_flags = old_flags & ~(IFF_UP | IFF_PROMISC);
592 if (nd_flags & NETDEV_UP) {
595 if (nd_flags & NETDEV_PROMISC) {
596 new_flags |= IFF_PROMISC;
598 if (new_flags != old_flags) {
599 error = set_flags(netdev, new_flags);
604 /* Looks up the ARP table entry for 'ip' on 'netdev'. If one exists and can be
605 * successfully retrieved, it stores the corresponding MAC address in 'mac' and
606 * returns 0. Otherwise, it returns a positive errno value; in particular,
607 * ENXIO indicates that there is not ARP table entry for 'ip' on 'netdev'. */
609 netdev_arp_lookup(const struct netdev *netdev,
610 uint32_t ip, uint8_t mac[ETH_ADDR_LEN])
613 struct sockaddr_in *pa;
616 memset(&r, 0, sizeof r);
617 pa = (struct sockaddr_in *) &r.arp_pa;
618 pa->sin_family = AF_INET;
619 pa->sin_addr.s_addr = ip;
621 r.arp_ha.sa_family = ARPHRD_ETHER;
623 strncpy(r.arp_dev, netdev->name, sizeof r.arp_dev);
624 retval = ioctl(af_inet_sock, SIOCGARP, &r) < 0 ? errno : 0;
626 memcpy(mac, r.arp_ha.sa_data, ETH_ADDR_LEN);
627 } else if (retval != ENXIO) {
628 VLOG_WARN("%s: could not look up ARP entry for "IP_FMT": %s",
629 netdev->name, IP_ARGS(&ip), strerror(retval));
634 static void restore_all_flags(void *aux);
636 /* Set up a signal hook to restore network device flags on program
644 fatal_signal_add_hook(restore_all_flags, NULL);
645 af_inet_sock = socket(AF_INET, SOCK_DGRAM, 0);
646 if (af_inet_sock < 0) {
647 fatal(errno, "socket(AF_INET)");
652 /* Restore the network device flags on 'netdev' to those that were active
653 * before we changed them. Returns 0 if successful, otherwise a positive
656 * To avoid reentry, the caller must ensure that fatal signals are blocked. */
658 restore_flags(struct netdev *netdev)
662 /* Get current flags. */
663 strncpy(ifr.ifr_name, netdev->name, sizeof ifr.ifr_name);
664 if (ioctl(netdev->fd, SIOCGIFFLAGS, &ifr) < 0) {
668 /* Restore flags that we might have changed, if necessary. */
669 if ((ifr.ifr_flags ^ netdev->save_flags) & (IFF_PROMISC | IFF_UP)) {
670 ifr.ifr_flags &= ~(IFF_PROMISC | IFF_UP);
671 ifr.ifr_flags |= netdev->save_flags & (IFF_PROMISC | IFF_UP);
672 if (ioctl(netdev->fd, SIOCSIFFLAGS, &ifr) < 0) {
680 /* Retores all the flags on all network devices that we modified. Called from
681 * a signal handler, so it does not attempt to report error conditions. */
683 restore_all_flags(void *aux UNUSED)
685 struct netdev *netdev;
686 LIST_FOR_EACH (netdev, struct netdev, node, &netdev_list) {
687 restore_flags(netdev);
692 get_flags(const struct netdev *netdev, int *flags)
695 strncpy(ifr.ifr_name, netdev->name, sizeof ifr.ifr_name);
696 if (ioctl(netdev->fd, SIOCGIFFLAGS, &ifr) < 0) {
697 VLOG_ERR("ioctl(SIOCGIFFLAGS) on %s device failed: %s",
698 netdev->name, strerror(errno));
701 *flags = ifr.ifr_flags;
706 set_flags(struct netdev *netdev, int flags)
709 strncpy(ifr.ifr_name, netdev->name, sizeof ifr.ifr_name);
710 ifr.ifr_flags = flags;
711 if (ioctl(netdev->fd, SIOCSIFFLAGS, &ifr) < 0) {
712 VLOG_ERR("ioctl(SIOCSIFFLAGS) on %s device failed: %s",
713 netdev->name, strerror(errno));