2 * Copyright (c) 2008, 2009, 2010, 2011, 2012, 2013, 2014 Nicira, Inc.
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at:
8 * http://www.apache.org/licenses/LICENSE-2.0
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
18 #include "socket-util.h"
19 #include <arpa/inet.h>
29 #include <sys/ioctl.h>
30 #include <sys/resource.h>
31 #include <sys/socket.h>
36 #include "dynamic-string.h"
37 #include "fatal-signal.h"
38 #include "ovs-thread.h"
40 #include "poll-loop.h"
43 #if AF_PACKET && LINUX_DATAPATH
44 #include <linux/if_packet.h>
47 #include "netlink-protocol.h"
48 #include "netlink-socket.h"
51 VLOG_DEFINE_THIS_MODULE(socket_util);
53 /* #ifdefs make it a pain to maintain code: you have to try to build both ways.
54 * Thus, this file compiles all of the code regardless of the target, by
55 * writing "if (LINUX_DATAPATH)" instead of "#ifdef __linux__". */
56 #ifndef LINUX_DATAPATH
57 #define LINUX_DATAPATH 0
64 /* Maximum length of the sun_path member in a struct sockaddr_un, excluding
65 * space for a null terminator. */
66 #define MAX_UN_LEN (sizeof(((struct sockaddr_un *) 0)->sun_path) - 1)
68 static int getsockopt_int(int fd, int level, int option, const char *optname,
71 /* Sets 'fd' to non-blocking mode. Returns 0 if successful, otherwise a
72 * positive errno value. */
74 set_nonblocking(int fd)
77 int flags = fcntl(fd, F_GETFL, 0);
79 if (fcntl(fd, F_SETFL, flags | O_NONBLOCK) != -1) {
82 VLOG_ERR("fcntl(F_SETFL) failed: %s", ovs_strerror(errno));
86 VLOG_ERR("fcntl(F_GETFL) failed: %s", ovs_strerror(errno));
90 unsigned long arg = 1;
91 if (ioctlsocket(fd, FIONBIO, &arg)) {
92 int error = sock_errno();
93 VLOG_ERR("set_nonblocking failed: %s", sock_strerror(error));
101 xset_nonblocking(int fd)
103 if (set_nonblocking(fd)) {
109 set_dscp(int fd, uint8_t dscp)
118 if (setsockopt(fd, IPPROTO_IP, IP_TOS, &val, sizeof val)) {
125 /* Translates 'host_name', which must be a string representation of an IP
126 * address, into a numeric IP address in '*addr'. Returns 0 if successful,
127 * otherwise a positive errno value. */
129 lookup_ip(const char *host_name, struct in_addr *addr)
131 if (!inet_pton(AF_INET, host_name, addr)) {
132 static struct vlog_rate_limit rl = VLOG_RATE_LIMIT_INIT(1, 5);
133 VLOG_ERR_RL(&rl, "\"%s\" is not a valid IP address", host_name);
139 /* Translates 'host_name', which must be a string representation of an IPv6
140 * address, into a numeric IPv6 address in '*addr'. Returns 0 if successful,
141 * otherwise a positive errno value. */
143 lookup_ipv6(const char *host_name, struct in6_addr *addr)
145 if (inet_pton(AF_INET6, host_name, addr) != 1) {
146 static struct vlog_rate_limit rl = VLOG_RATE_LIMIT_INIT(1, 5);
147 VLOG_ERR_RL(&rl, "\"%s\" is not a valid IPv6 address", host_name);
153 /* Translates 'host_name', which must be a host name or a string representation
154 * of an IP address, into a numeric IP address in '*addr'. Returns 0 if
155 * successful, otherwise a positive errno value.
157 * Most Open vSwitch code should not use this because it causes deadlocks:
158 * getaddrinfo() sends out a DNS request but that starts a new flow for which
159 * OVS must set up a flow, but it can't because it's waiting for a DNS reply.
160 * The synchronous lookup also delays other activity. (Of course we can solve
161 * this but it doesn't seem worthwhile quite yet.) */
163 lookup_hostname(const char *host_name, struct in_addr *addr)
165 struct addrinfo *result;
166 struct addrinfo hints;
168 if (inet_pton(AF_INET, host_name, addr)) {
172 memset(&hints, 0, sizeof hints);
173 hints.ai_family = AF_INET;
175 switch (getaddrinfo(host_name, NULL, &hints, &result)) {
177 *addr = ALIGNED_CAST(struct sockaddr_in *,
178 result->ai_addr)->sin_addr;
179 freeaddrinfo(result);
182 #ifdef EAI_ADDRFAMILY
203 #if defined (EAI_NODATA) && EAI_NODATA != EAI_NONAME
219 check_connection_completion(int fd)
221 static struct vlog_rate_limit rl = VLOG_RATE_LIMIT_INIT(5, 10);
226 pfd.events = POLLOUT;
230 retval = poll(&pfd, 1, 0);
231 } while (retval < 0 && errno == EINTR);
233 retval = WSAPoll(&pfd, 1, 0);
236 if (pfd.revents & POLLERR) {
237 ssize_t n = send(fd, "", 1, 0);
241 VLOG_ERR_RL(&rl, "poll return POLLERR but send succeeded");
246 } else if (retval < 0) {
247 VLOG_ERR_RL(&rl, "poll: %s", sock_strerror(sock_errno()));
254 /* Drain all the data currently in the receive queue of a datagram socket (and
255 * possibly additional data). There is no way to know how many packets are in
256 * the receive queue, but we do know that the total number of bytes queued does
257 * not exceed the receive buffer size, so we pull packets until none are left
258 * or we've read that many bytes. */
264 rcvbuf = get_socket_rcvbuf(fd);
270 /* In Linux, specifying MSG_TRUNC in the flags argument causes the
271 * datagram length to be returned, even if that is longer than the
272 * buffer provided. Thus, we can use a 1-byte buffer to discard the
273 * incoming datagram and still be able to account how many bytes were
274 * removed from the receive buffer.
276 * On other Unix-like OSes, MSG_TRUNC has no effect in the flags
278 char buffer[LINUX_DATAPATH ? 1 : 2048];
279 ssize_t n_bytes = recv(fd, buffer, sizeof buffer, MSG_TRUNC);
280 if (n_bytes <= 0 || n_bytes >= rcvbuf) {
288 /* Returns the size of socket 'sock''s receive buffer (SO_RCVBUF), or a
289 * negative errno value if an error occurs. */
291 get_socket_rcvbuf(int sock)
296 error = getsockopt_int(sock, SOL_SOCKET, SO_RCVBUF, "SO_RCVBUF", &rcvbuf);
297 return error ? -error : rcvbuf;
300 /* Reads and discards up to 'n' datagrams from 'fd', stopping as soon as no
301 * more data can be immediately read. ('fd' should therefore be in
302 * non-blocking mode.)*/
304 drain_fd(int fd, size_t n_packets)
306 for (; n_packets > 0; n_packets--) {
307 /* 'buffer' only needs to be 1 byte long in most circumstances. This
308 * size is defensive against the possibility that we someday want to
309 * use a Linux tap device without TUN_NO_PI, in which case a buffer
310 * smaller than sizeof(struct tun_pi) will give EINVAL on read. */
312 if (read(fd, buffer, sizeof buffer) <= 0) {
319 /* Attempts to shorten 'name' by opening a file descriptor for the directory
320 * part of the name and indirecting through /proc/self/fd/<dirfd>/<basename>.
321 * On systems with Linux-like /proc, this works as long as <basename> isn't too
324 * On success, returns 0 and stores the short name in 'short_name' and a
325 * directory file descriptor to eventually be closed in '*dirfpd'. */
327 shorten_name_via_proc(const char *name, char short_name[MAX_UN_LEN + 1],
334 if (!LINUX_DATAPATH) {
338 dir = dir_name(name);
339 dirfd = open(dir, O_DIRECTORY | O_RDONLY);
341 static struct vlog_rate_limit rl = VLOG_RATE_LIMIT_INIT(1, 1);
344 VLOG_WARN_RL(&rl, "%s: open failed (%s)", dir, ovs_strerror(error));
351 base = base_name(name);
352 len = snprintf(short_name, MAX_UN_LEN + 1,
353 "/proc/self/fd/%d/%s", dirfd, base);
356 if (len >= 0 && len <= MAX_UN_LEN) {
365 /* Attempts to shorten 'name' by creating a symlink for the directory part of
366 * the name and indirecting through <symlink>/<basename>. This works on
367 * systems that support symlinks, as long as <basename> isn't too long.
369 * On success, returns 0 and stores the short name in 'short_name' and the
370 * symbolic link to eventually delete in 'linkname'. */
372 shorten_name_via_symlink(const char *name, char short_name[MAX_UN_LEN + 1],
373 char linkname[MAX_UN_LEN + 1])
375 char *abs, *dir, *base;
380 abs = abs_file_name(NULL, name);
382 base = base_name(abs);
385 tmpdir = getenv("TMPDIR");
386 if (tmpdir == NULL) {
390 for (i = 0; i < 1000; i++) {
393 len = snprintf(linkname, MAX_UN_LEN + 1,
394 "%s/ovs-un-c-%"PRIu32, tmpdir, random_uint32());
395 error = (len < 0 || len > MAX_UN_LEN ? ENAMETOOLONG
396 : symlink(dir, linkname) ? errno
398 if (error != EEXIST) {
406 fatal_signal_add_file_to_unlink(linkname);
408 len = snprintf(short_name, MAX_UN_LEN + 1, "%s/%s", linkname, base);
409 if (len < 0 || len > MAX_UN_LEN) {
410 fatal_signal_unlink_file_now(linkname);
411 error = ENAMETOOLONG;
424 /* Stores in '*un' a sockaddr_un that refers to file 'name'. Stores in
425 * '*un_len' the size of the sockaddr_un.
427 * Returns 0 on success, otherwise a positive errno value.
429 * Uses '*dirfdp' and 'linkname' to store references to data when the caller no
430 * longer needs to use 'un'. On success, freeing these references with
431 * free_sockaddr_un() is mandatory to avoid a leak; on failure, freeing them is
432 * unnecessary but harmless. */
434 make_sockaddr_un(const char *name, struct sockaddr_un *un, socklen_t *un_len,
435 int *dirfdp, char linkname[MAX_UN_LEN + 1])
437 char short_name[MAX_UN_LEN + 1];
441 if (strlen(name) > MAX_UN_LEN) {
442 /* 'name' is too long to fit in a sockaddr_un. Try a workaround. */
443 int error = shorten_name_via_proc(name, short_name, dirfdp);
444 if (error == ENAMETOOLONG) {
445 error = shorten_name_via_symlink(name, short_name, linkname);
448 static struct vlog_rate_limit rl = VLOG_RATE_LIMIT_INIT(1, 1);
450 VLOG_WARN_RL(&rl, "Unix socket name %s is longer than maximum "
451 "%"PRIuSIZE" bytes", name, MAX_UN_LEN);
458 un->sun_family = AF_UNIX;
459 ovs_strzcpy(un->sun_path, name, sizeof un->sun_path);
460 *un_len = (offsetof(struct sockaddr_un, sun_path)
461 + strlen (un->sun_path) + 1);
465 /* Clean up after make_sockaddr_un(). */
467 free_sockaddr_un(int dirfd, const char *linkname)
473 fatal_signal_unlink_file_now(linkname);
477 /* Binds Unix domain socket 'fd' to a file with permissions 0700. */
479 bind_unix_socket(int fd, struct sockaddr *sun, socklen_t sun_len)
481 /* According to _Unix Network Programming_, umask should affect bind(). */
482 mode_t old_umask = umask(0077);
483 int error = bind(fd, sun, sun_len) ? errno : 0;
488 /* Creates a Unix domain socket in the given 'style' (either SOCK_DGRAM or
489 * SOCK_STREAM) that is bound to '*bind_path' (if 'bind_path' is non-null) and
490 * connected to '*connect_path' (if 'connect_path' is non-null). If 'nonblock'
491 * is true, the socket is made non-blocking.
493 * Returns the socket's fd if successful, otherwise a negative errno value. */
495 make_unix_socket(int style, bool nonblock,
496 const char *bind_path, const char *connect_path)
501 fd = socket(PF_UNIX, style, 0);
506 /* Set nonblocking mode right away, if we want it. This prevents blocking
507 * in connect(), if connect_path != NULL. (In turn, that's a corner case:
508 * it will only happen if style is SOCK_STREAM or SOCK_SEQPACKET, and only
509 * if a backlog of un-accepted connections has built up in the kernel.) */
511 error = set_nonblocking(fd);
518 char linkname[MAX_UN_LEN + 1];
519 struct sockaddr_un un;
523 if (unlink(bind_path) && errno != ENOENT) {
524 VLOG_WARN("unlinking \"%s\": %s\n",
525 bind_path, ovs_strerror(errno));
527 fatal_signal_add_file_to_unlink(bind_path);
529 error = make_sockaddr_un(bind_path, &un, &un_len, &dirfd, linkname);
531 error = bind_unix_socket(fd, (struct sockaddr *) &un, un_len);
533 free_sockaddr_un(dirfd, linkname);
541 char linkname[MAX_UN_LEN + 1];
542 struct sockaddr_un un;
546 error = make_sockaddr_un(connect_path, &un, &un_len, &dirfd, linkname);
548 && connect(fd, (struct sockaddr*) &un, un_len)
549 && errno != EINPROGRESS) {
552 free_sockaddr_un(dirfd, linkname);
562 if (error == EAGAIN) {
566 fatal_signal_unlink_file_now(bind_path);
573 get_unix_name_len(socklen_t sun_len)
575 return (sun_len >= offsetof(struct sockaddr_un, sun_path)
576 ? sun_len - offsetof(struct sockaddr_un, sun_path)
582 guess_netmask(ovs_be32 ip_)
584 uint32_t ip = ntohl(ip_);
585 return ((ip >> 31) == 0 ? htonl(0xff000000) /* Class A */
586 : (ip >> 30) == 2 ? htonl(0xffff0000) /* Class B */
587 : (ip >> 29) == 6 ? htonl(0xffffff00) /* Class C */
588 : htonl(0)); /* ??? */
591 /* This is like strsep() except:
593 * - The separator string is ":".
595 * - Square brackets [] quote ":" separators and are removed from the
598 parse_bracketed_token(char **pp)
604 } else if (*p == '\0') {
607 } else if (*p == '[') {
609 char *end = start + strcspn(start, "]");
610 *pp = (*end == '\0' ? NULL
611 : end[1] == ':' ? end + 2
617 char *end = start + strcspn(start, ":");
618 *pp = *end == '\0' ? NULL : end + 1;
625 parse_sockaddr_components(struct sockaddr_storage *ss,
627 const char *port_s, uint16_t default_port,
630 struct sockaddr_in *sin = ALIGNED_CAST(struct sockaddr_in *, ss);
633 if (port_s && port_s[0]) {
634 if (!str_to_int(port_s, 10, &port) || port < 0 || port > 65535) {
635 VLOG_ERR("%s: bad port number \"%s\"", s, port_s);
641 memset(ss, 0, sizeof *ss);
642 if (strchr(host_s, ':')) {
643 struct sockaddr_in6 *sin6
644 = ALIGNED_CAST(struct sockaddr_in6 *, ss);
646 sin6->sin6_family = AF_INET6;
647 sin6->sin6_port = htons(port);
648 if (!inet_pton(AF_INET6, host_s, sin6->sin6_addr.s6_addr)) {
649 VLOG_ERR("%s: bad IPv6 address \"%s\"", s, host_s);
653 sin->sin_family = AF_INET;
654 sin->sin_port = htons(port);
655 if (!inet_pton(AF_INET, host_s, &sin->sin_addr.s_addr)) {
656 VLOG_ERR("%s: bad IPv4 address \"%s\"", s, host_s);
664 memset(ss, 0, sizeof *ss);
668 /* Parses 'target', which should be a string in the format "<host>[:<port>]".
669 * <host>, which is required, may be an IPv4 address or an IPv6 address
670 * enclosed in square brackets. If 'default_port' is nonzero then <port> is
671 * optional and defaults to 'default_port'.
673 * On success, returns true and stores the parsed remote address into '*ss'.
674 * On failure, logs an error, stores zeros into '*ss', and returns false. */
676 inet_parse_active(const char *target_, uint16_t default_port,
677 struct sockaddr_storage *ss)
679 char *target = xstrdup(target_);
686 host = parse_bracketed_token(&p);
687 port = parse_bracketed_token(&p);
689 VLOG_ERR("%s: host must be specified", target_);
691 } else if (!port && !default_port) {
692 VLOG_ERR("%s: port must be specified", target_);
695 ok = parse_sockaddr_components(ss, host, port, default_port, target_);
698 memset(ss, 0, sizeof *ss);
705 /* Opens a non-blocking IPv4 or IPv6 socket of the specified 'style' and
706 * connects to 'target', which should be a string in the format
707 * "<host>[:<port>]". <host>, which is required, may be an IPv4 address or an
708 * IPv6 address enclosed in square brackets. If 'default_port' is nonzero then
709 * <port> is optional and defaults to 'default_port'.
711 * 'style' should be SOCK_STREAM (for TCP) or SOCK_DGRAM (for UDP).
713 * On success, returns 0 (indicating connection complete) or EAGAIN (indicating
714 * connection in progress), in which case the new file descriptor is stored
715 * into '*fdp'. On failure, returns a positive errno value other than EAGAIN
716 * and stores -1 into '*fdp'.
718 * If 'ss' is non-null, then on success stores the target address into '*ss'.
720 * 'dscp' becomes the DSCP bits in the IP headers for the new connection. It
721 * should be in the range [0, 63] and will automatically be shifted to the
722 * appropriately place in the IP tos field. */
724 inet_open_active(int style, const char *target, uint16_t default_port,
725 struct sockaddr_storage *ssp, int *fdp, uint8_t dscp)
727 struct sockaddr_storage ss;
732 if (!inet_parse_active(target, default_port, &ss)) {
733 error = EAFNOSUPPORT;
737 /* Create non-blocking socket. */
738 fd = socket(ss.ss_family, style, 0);
740 error = sock_errno();
741 VLOG_ERR("%s: socket: %s", target, sock_strerror(error));
744 error = set_nonblocking(fd);
749 /* The dscp bits must be configured before connect() to ensure that the
750 * TOS field is set during the connection establishment. If set after
751 * connect(), the handshake SYN frames will be sent with a TOS of 0. */
752 error = set_dscp(fd, dscp);
754 VLOG_ERR("%s: socket: %s", target, sock_strerror(error));
759 error = connect(fd, (struct sockaddr *) &ss, ss_length(&ss)) == 0
762 if (error == EINPROGRESS
764 || error == WSAEALREADY || error == WSAEWOULDBLOCK
771 if (error && error != EAGAIN) {
773 memset(ssp, 0, sizeof *ssp);
788 /* Parses 'target', which should be a string in the format "[<port>][:<host>]":
790 * - If 'default_port' is -1, then <port> is required. Otherwise, if
791 * <port> is omitted, then 'default_port' is used instead.
793 * - If <port> (or 'default_port', if used) is 0, then no port is bound
794 * and the TCP/IP stack will select a port.
796 * - <host> is optional. If supplied, it may be an IPv4 address or an
797 * IPv6 address enclosed in square brackets. If omitted, the IP address
800 * If successful, stores the address into '*ss' and returns true; otherwise
801 * zeros '*ss' and returns false. */
803 inet_parse_passive(const char *target_, int default_port,
804 struct sockaddr_storage *ss)
806 char *target = xstrdup(target_);
813 port = parse_bracketed_token(&p);
814 host = parse_bracketed_token(&p);
815 if (!port && default_port < 0) {
816 VLOG_ERR("%s: port must be specified", target_);
819 ok = parse_sockaddr_components(ss, host ? host : "0.0.0.0",
820 port, default_port, target_);
823 memset(ss, 0, sizeof *ss);
830 /* Opens a non-blocking IPv4 or IPv6 socket of the specified 'style', binds to
831 * 'target', and listens for incoming connections. Parses 'target' in the same
832 * way was inet_parse_passive().
834 * 'style' should be SOCK_STREAM (for TCP) or SOCK_DGRAM (for UDP).
836 * For TCP, the socket will have SO_REUSEADDR turned on.
838 * On success, returns a non-negative file descriptor. On failure, returns a
839 * negative errno value.
841 * If 'ss' is non-null, then on success stores the bound address into '*ss'.
843 * 'dscp' becomes the DSCP bits in the IP headers for the new connection. It
844 * should be in the range [0, 63] and will automatically be shifted to the
845 * appropriately place in the IP tos field. */
847 inet_open_passive(int style, const char *target, int default_port,
848 struct sockaddr_storage *ssp, uint8_t dscp)
850 bool kernel_chooses_port;
851 struct sockaddr_storage ss;
853 unsigned int yes = 1;
855 if (!inet_parse_passive(target, default_port, &ss)) {
856 return -EAFNOSUPPORT;
858 kernel_chooses_port = ss_get_port(&ss) == 0;
860 /* Create non-blocking socket, set SO_REUSEADDR. */
861 fd = socket(ss.ss_family, style, 0);
863 error = sock_errno();
864 VLOG_ERR("%s: socket: %s", target, sock_strerror(error));
867 error = set_nonblocking(fd);
871 if (style == SOCK_STREAM
872 && setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &yes, sizeof yes) < 0) {
873 error = sock_errno();
874 VLOG_ERR("%s: setsockopt(SO_REUSEADDR): %s",
875 target, sock_strerror(error));
880 if (bind(fd, (struct sockaddr *) &ss, ss_length(&ss)) < 0) {
881 error = sock_errno();
882 VLOG_ERR("%s: bind: %s", target, sock_strerror(error));
886 /* The dscp bits must be configured before connect() to ensure that the TOS
887 * field is set during the connection establishment. If set after
888 * connect(), the handshake SYN frames will be sent with a TOS of 0. */
889 error = set_dscp(fd, dscp);
891 VLOG_ERR("%s: socket: %s", target, sock_strerror(error));
896 if (style == SOCK_STREAM && listen(fd, 10) < 0) {
897 error = sock_errno();
898 VLOG_ERR("%s: listen: %s", target, sock_strerror(error));
902 if (ssp || kernel_chooses_port) {
903 socklen_t ss_len = sizeof ss;
904 if (getsockname(fd, (struct sockaddr *) &ss, &ss_len) < 0) {
905 error = sock_errno();
906 VLOG_ERR("%s: getsockname: %s", target, sock_strerror(error));
909 if (kernel_chooses_port) {
910 VLOG_INFO("%s: listening on port %"PRIu16,
911 target, ss_get_port(&ss));
922 memset(ssp, 0, sizeof *ssp);
928 /* Returns a readable and writable fd for /dev/null, if successful, otherwise
929 * a negative errno value. The caller must not close the returned fd (because
930 * the same fd will be handed out to subsequent callers). */
934 static struct ovsthread_once once = OVSTHREAD_ONCE_INITIALIZER;
937 if (ovsthread_once_start(&once)) {
938 null_fd = open("/dev/null", O_RDWR);
941 VLOG_ERR("could not open /dev/null: %s", ovs_strerror(error));
944 ovsthread_once_done(&once);
951 read_fully(int fd, void *p_, size_t size, size_t *bytes_read)
957 ssize_t retval = read(fd, p, size);
959 *bytes_read += retval;
962 } else if (retval == 0) {
964 } else if (errno != EINTR) {
972 write_fully(int fd, const void *p_, size_t size, size_t *bytes_written)
974 const uint8_t *p = p_;
978 ssize_t retval = write(fd, p, size);
980 *bytes_written += retval;
983 } else if (retval == 0) {
984 VLOG_WARN("write returned 0");
986 } else if (errno != EINTR) {
993 /* Given file name 'file_name', fsyncs the directory in which it is contained.
994 * Returns 0 if successful, otherwise a positive errno value. */
996 fsync_parent_dir(const char *file_name)
1003 dir = dir_name(file_name);
1004 fd = open(dir, O_RDONLY);
1007 if (errno == EINVAL || errno == EROFS) {
1008 /* This directory does not support synchronization. Not
1009 * really an error. */
1012 VLOG_ERR("%s: fsync failed (%s)", dir, ovs_strerror(error));
1018 VLOG_ERR("%s: open failed (%s)", dir, ovs_strerror(error));
1026 /* Obtains the modification time of the file named 'file_name' to the greatest
1027 * supported precision. If successful, stores the mtime in '*mtime' and
1028 * returns 0. On error, returns a positive errno value and stores zeros in
1031 get_mtime(const char *file_name, struct timespec *mtime)
1035 if (!stat(file_name, &s)) {
1036 mtime->tv_sec = s.st_mtime;
1038 #if HAVE_STRUCT_STAT_ST_MTIM_TV_NSEC
1039 mtime->tv_nsec = s.st_mtim.tv_nsec;
1040 #elif HAVE_STRUCT_STAT_ST_MTIMENSEC
1041 mtime->tv_nsec = s.st_mtimensec;
1048 mtime->tv_sec = mtime->tv_nsec = 0;
1057 VLOG_FATAL("failed to create pipe (%s)", ovs_strerror(errno));
1062 xpipe_nonblocking(int fds[2])
1065 xset_nonblocking(fds[0]);
1066 xset_nonblocking(fds[1]);
1070 getsockopt_int(int fd, int level, int option, const char *optname, int *valuep)
1072 static struct vlog_rate_limit rl = VLOG_RATE_LIMIT_INIT(5, 10);
1078 if (getsockopt(fd, level, option, &value, &len)) {
1079 error = sock_errno();
1080 VLOG_ERR_RL(&rl, "getsockopt(%s): %s", optname, sock_strerror(error));
1081 } else if (len != sizeof value) {
1083 VLOG_ERR_RL(&rl, "getsockopt(%s): value is %u bytes (expected %"PRIuSIZE")",
1084 optname, (unsigned int) len, sizeof value);
1089 *valuep = error ? 0 : value;
1094 describe_sockaddr(struct ds *string, int fd,
1095 int (*getaddr)(int, struct sockaddr *, socklen_t *))
1097 struct sockaddr_storage ss;
1098 socklen_t len = sizeof ss;
1100 if (!getaddr(fd, (struct sockaddr *) &ss, &len)) {
1101 if (ss.ss_family == AF_INET || ss.ss_family == AF_INET6) {
1102 char addrbuf[SS_NTOP_BUFSIZE];
1104 ds_put_format(string, "%s:%"PRIu16,
1105 ss_format_address(&ss, addrbuf, sizeof addrbuf),
1108 } else if (ss.ss_family == AF_UNIX) {
1109 struct sockaddr_un sun;
1113 memcpy(&sun, &ss, sizeof sun);
1114 maxlen = len - offsetof(struct sockaddr_un, sun_path);
1115 null = memchr(sun.sun_path, '\0', maxlen);
1116 ds_put_buffer(string, sun.sun_path,
1117 null ? null - sun.sun_path : maxlen);
1121 else if (ss.ss_family == AF_NETLINK) {
1124 /* SO_PROTOCOL was introduced in 2.6.32. Support it regardless of the version
1125 * of the Linux kernel headers in use at build time. */
1127 #define SO_PROTOCOL 38
1130 if (!getsockopt_int(fd, SOL_SOCKET, SO_PROTOCOL, "SO_PROTOCOL",
1134 ds_put_cstr(string, "NETLINK_ROUTE");
1137 case NETLINK_GENERIC:
1138 ds_put_cstr(string, "NETLINK_GENERIC");
1142 ds_put_format(string, "AF_NETLINK family %d", protocol);
1146 ds_put_cstr(string, "AF_NETLINK");
1150 #if AF_PACKET && LINUX_DATAPATH
1151 else if (ss.ss_family == AF_PACKET) {
1152 struct sockaddr_ll sll;
1154 memcpy(&sll, &ss, sizeof sll);
1155 ds_put_cstr(string, "AF_PACKET");
1156 if (sll.sll_ifindex) {
1157 char name[IFNAMSIZ];
1159 if (if_indextoname(sll.sll_ifindex, name)) {
1160 ds_put_format(string, "(%s)", name);
1162 ds_put_format(string, "(ifindex=%d)", sll.sll_ifindex);
1165 if (sll.sll_protocol) {
1166 ds_put_format(string, "(protocol=0x%"PRIu16")",
1167 ntohs(sll.sll_protocol));
1171 else if (ss.ss_family == AF_UNSPEC) {
1172 ds_put_cstr(string, "AF_UNSPEC");
1174 ds_put_format(string, "AF_%d", (int) ss.ss_family);
1180 #ifdef LINUX_DATAPATH
1182 put_fd_filename(struct ds *string, int fd)
1188 linkname = xasprintf("/proc/self/fd/%d", fd);
1189 n = readlink(linkname, buf, sizeof buf);
1191 ds_put_char(string, ' ');
1192 ds_put_buffer(string, buf, n);
1193 if (n > sizeof buf) {
1194 ds_put_cstr(string, "...");
1201 /* Returns a malloc()'d string describing 'fd', for use in logging. */
1210 if (fstat(fd, &s)) {
1211 ds_put_format(&string, "fstat failed (%s)", ovs_strerror(errno));
1212 } else if (S_ISSOCK(s.st_mode)) {
1213 describe_sockaddr(&string, fd, getsockname);
1214 ds_put_cstr(&string, "<->");
1215 describe_sockaddr(&string, fd, getpeername);
1217 ds_put_cstr(&string, (isatty(fd) ? "tty"
1218 : S_ISDIR(s.st_mode) ? "directory"
1219 : S_ISCHR(s.st_mode) ? "character device"
1220 : S_ISBLK(s.st_mode) ? "block device"
1221 : S_ISREG(s.st_mode) ? "file"
1222 : S_ISFIFO(s.st_mode) ? "FIFO"
1223 : S_ISLNK(s.st_mode) ? "symbolic link"
1225 #ifdef LINUX_DATAPATH
1226 put_fd_filename(&string, fd);
1230 ds_put_format(&string,"file descriptor");
1232 return ds_steal_cstr(&string);
1236 /* Calls ioctl() on an AF_INET sock, passing the specified 'command' and
1237 * 'arg'. Returns 0 if successful, otherwise a positive errno value. */
1239 af_inet_ioctl(unsigned long int command, const void *arg)
1241 static struct ovsthread_once once = OVSTHREAD_ONCE_INITIALIZER;
1244 if (ovsthread_once_start(&once)) {
1245 sock = socket(AF_INET, SOCK_DGRAM, 0);
1247 int error = sock_errno();
1248 VLOG_ERR("failed to create inet socket: %s", sock_strerror(error));
1251 ovsthread_once_done(&once);
1254 return (sock < 0 ? -sock
1255 : ioctl(sock, command, arg) == -1 ? errno
1260 af_inet_ifreq_ioctl(const char *name, struct ifreq *ifr, unsigned long int cmd,
1261 const char *cmd_name)
1265 ovs_strzcpy(ifr->ifr_name, name, sizeof ifr->ifr_name);
1266 error = af_inet_ioctl(cmd, ifr);
1268 static struct vlog_rate_limit rl = VLOG_RATE_LIMIT_INIT(5, 20);
1269 VLOG_DBG_RL(&rl, "%s: ioctl(%s) failed: %s", name, cmd_name,
1270 ovs_strerror(error));
1276 /* sockaddr_storage helpers. */
1278 /* Returns the IPv4 or IPv6 port in 'ss'. */
1280 ss_get_port(const struct sockaddr_storage *ss)
1282 if (ss->ss_family == AF_INET) {
1283 const struct sockaddr_in *sin
1284 = ALIGNED_CAST(const struct sockaddr_in *, ss);
1285 return ntohs(sin->sin_port);
1286 } else if (ss->ss_family == AF_INET6) {
1287 const struct sockaddr_in6 *sin6
1288 = ALIGNED_CAST(const struct sockaddr_in6 *, ss);
1289 return ntohs(sin6->sin6_port);
1295 /* Formats the IPv4 or IPv6 address in 'ss' into the 'bufsize' bytes in 'buf'.
1296 * If 'ss' is an IPv6 address, puts square brackets around the address.
1297 * 'bufsize' should be at least SS_NTOP_BUFSIZE.
1301 ss_format_address(const struct sockaddr_storage *ss,
1302 char *buf, size_t bufsize)
1304 ovs_assert(bufsize >= SS_NTOP_BUFSIZE);
1305 if (ss->ss_family == AF_INET) {
1306 const struct sockaddr_in *sin
1307 = ALIGNED_CAST(const struct sockaddr_in *, ss);
1309 snprintf(buf, bufsize, IP_FMT, IP_ARGS(sin->sin_addr.s_addr));
1310 } else if (ss->ss_family == AF_INET6) {
1311 const struct sockaddr_in6 *sin6
1312 = ALIGNED_CAST(const struct sockaddr_in6 *, ss);
1315 inet_ntop(AF_INET6, sin6->sin6_addr.s6_addr, buf + 1, bufsize - 1);
1316 strcpy(strchr(buf, '\0'), "]");
1325 ss_length(const struct sockaddr_storage *ss)
1327 switch (ss->ss_family) {
1329 return sizeof(struct sockaddr_in);
1332 return sizeof(struct sockaddr_in6);
1339 /* For Windows socket calls, 'errno' is not set. One has to call
1340 * WSAGetLastError() to get the error number and then pass it to
1341 * this function to get the correct error string.
1343 * ovs_strerror() calls strerror_r() and would not get the correct error
1344 * string for Windows sockets, but is good for POSIX. */
1346 sock_strerror(int error)
1349 return ovs_format_message(error);
1351 return ovs_strerror(error);