2 * Copyright (c) 2008, 2009, 2010, 2011, 2012, 2013 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/resource.h>
30 #include <sys/socket.h>
35 #include "dynamic-string.h"
36 #include "fatal-signal.h"
38 #include "poll-loop.h"
41 #if AF_PACKET && LINUX_DATAPATH
42 #include <linux/if_packet.h>
45 #include "netlink-protocol.h"
46 #include "netlink-socket.h"
49 VLOG_DEFINE_THIS_MODULE(socket_util);
51 /* #ifdefs make it a pain to maintain code: you have to try to build both ways.
52 * Thus, this file compiles all of the code regardless of the target, by
53 * writing "if (LINUX_DATAPATH)" instead of "#ifdef __linux__". */
54 #ifndef LINUX_DATAPATH
55 #define LINUX_DATAPATH 0
62 static int getsockopt_int(int fd, int level, int option, const char *optname,
65 /* Sets 'fd' to non-blocking mode. Returns 0 if successful, otherwise a
66 * positive errno value. */
68 set_nonblocking(int fd)
70 int flags = fcntl(fd, F_GETFL, 0);
72 if (fcntl(fd, F_SETFL, flags | O_NONBLOCK) != -1) {
75 VLOG_ERR("fcntl(F_SETFL) failed: %s", ovs_strerror(errno));
79 VLOG_ERR("fcntl(F_GETFL) failed: %s", ovs_strerror(errno));
85 xset_nonblocking(int fd)
87 if (set_nonblocking(fd)) {
93 set_dscp(int fd, uint8_t dscp)
102 if (setsockopt(fd, IPPROTO_IP, IP_TOS, &val, sizeof val)) {
110 rlim_is_finite(rlim_t limit)
112 if (limit == RLIM_INFINITY) {
116 #ifdef RLIM_SAVED_CUR /* FreeBSD 8.0 lacks RLIM_SAVED_CUR. */
117 if (limit == RLIM_SAVED_CUR) {
122 #ifdef RLIM_SAVED_MAX /* FreeBSD 8.0 lacks RLIM_SAVED_MAX. */
123 if (limit == RLIM_SAVED_MAX) {
131 /* Returns the maximum valid FD value, plus 1. */
135 static struct ovsthread_once once = OVSTHREAD_ONCE_INITIALIZER;
138 if (ovsthread_once_start(&once)) {
140 if (!getrlimit(RLIMIT_NOFILE, &r) && rlim_is_finite(r.rlim_cur)) {
141 max_fds = r.rlim_cur;
143 VLOG_WARN("failed to obtain fd limit, defaulting to 1024");
146 ovsthread_once_done(&once);
152 /* Translates 'host_name', which must be a string representation of an IP
153 * address, into a numeric IP address in '*addr'. Returns 0 if successful,
154 * otherwise a positive errno value. */
156 lookup_ip(const char *host_name, struct in_addr *addr)
158 if (!inet_aton(host_name, addr)) {
159 static struct vlog_rate_limit rl = VLOG_RATE_LIMIT_INIT(1, 5);
160 VLOG_ERR_RL(&rl, "\"%s\" is not a valid IP address", host_name);
166 /* Translates 'host_name', which must be a string representation of an IPv6
167 * address, into a numeric IPv6 address in '*addr'. Returns 0 if successful,
168 * otherwise a positive errno value. */
170 lookup_ipv6(const char *host_name, struct in6_addr *addr)
172 if (inet_pton(AF_INET6, host_name, addr) != 1) {
173 static struct vlog_rate_limit rl = VLOG_RATE_LIMIT_INIT(1, 5);
174 VLOG_ERR_RL(&rl, "\"%s\" is not a valid IPv6 address", host_name);
180 /* Translates 'host_name', which must be a host name or a string representation
181 * of an IP address, into a numeric IP address in '*addr'. Returns 0 if
182 * successful, otherwise a positive errno value.
184 * Most Open vSwitch code should not use this because it causes deadlocks:
185 * getaddrinfo() sends out a DNS request but that starts a new flow for which
186 * OVS must set up a flow, but it can't because it's waiting for a DNS reply.
187 * The synchronous lookup also delays other activity. (Of course we can solve
188 * this but it doesn't seem worthwhile quite yet.) */
190 lookup_hostname(const char *host_name, struct in_addr *addr)
192 struct addrinfo *result;
193 struct addrinfo hints;
195 if (inet_aton(host_name, addr)) {
199 memset(&hints, 0, sizeof hints);
200 hints.ai_family = AF_INET;
202 switch (getaddrinfo(host_name, NULL, &hints, &result)) {
204 *addr = ALIGNED_CAST(struct sockaddr_in *,
205 result->ai_addr)->sin_addr;
206 freeaddrinfo(result);
209 #ifdef EAI_ADDRFAMILY
244 check_connection_completion(int fd)
246 static struct vlog_rate_limit rl = VLOG_RATE_LIMIT_INIT(5, 10);
251 pfd.events = POLLOUT;
253 retval = poll(&pfd, 1, 0);
254 } while (retval < 0 && errno == EINTR);
256 if (pfd.revents & POLLERR) {
257 ssize_t n = send(fd, "", 1, MSG_DONTWAIT);
261 VLOG_ERR_RL(&rl, "poll return POLLERR but send succeeded");
266 } else if (retval < 0) {
267 VLOG_ERR_RL(&rl, "poll: %s", ovs_strerror(errno));
274 /* Drain all the data currently in the receive queue of a datagram socket (and
275 * possibly additional data). There is no way to know how many packets are in
276 * the receive queue, but we do know that the total number of bytes queued does
277 * not exceed the receive buffer size, so we pull packets until none are left
278 * or we've read that many bytes. */
284 rcvbuf = get_socket_rcvbuf(fd);
290 /* In Linux, specifying MSG_TRUNC in the flags argument causes the
291 * datagram length to be returned, even if that is longer than the
292 * buffer provided. Thus, we can use a 1-byte buffer to discard the
293 * incoming datagram and still be able to account how many bytes were
294 * removed from the receive buffer.
296 * On other Unix-like OSes, MSG_TRUNC has no effect in the flags
298 char buffer[LINUX_DATAPATH ? 1 : 2048];
299 ssize_t n_bytes = recv(fd, buffer, sizeof buffer,
300 MSG_TRUNC | MSG_DONTWAIT);
301 if (n_bytes <= 0 || n_bytes >= rcvbuf) {
309 /* Returns the size of socket 'sock''s receive buffer (SO_RCVBUF), or a
310 * negative errno value if an error occurs. */
312 get_socket_rcvbuf(int sock)
317 error = getsockopt_int(sock, SOL_SOCKET, SO_RCVBUF, "SO_RCVBUF", &rcvbuf);
318 return error ? -error : rcvbuf;
321 /* Reads and discards up to 'n' datagrams from 'fd', stopping as soon as no
322 * more data can be immediately read. ('fd' should therefore be in
323 * non-blocking mode.)*/
325 drain_fd(int fd, size_t n_packets)
327 for (; n_packets > 0; n_packets--) {
328 /* 'buffer' only needs to be 1 byte long in most circumstances. This
329 * size is defensive against the possibility that we someday want to
330 * use a Linux tap device without TUN_NO_PI, in which case a buffer
331 * smaller than sizeof(struct tun_pi) will give EINVAL on read. */
333 if (read(fd, buffer, sizeof buffer) <= 0) {
339 /* Stores in '*un' a sockaddr_un that refers to file 'name'. Stores in
340 * '*un_len' the size of the sockaddr_un. */
342 make_sockaddr_un__(const char *name, struct sockaddr_un *un, socklen_t *un_len)
344 un->sun_family = AF_UNIX;
345 ovs_strzcpy(un->sun_path, name, sizeof un->sun_path);
346 *un_len = (offsetof(struct sockaddr_un, sun_path)
347 + strlen (un->sun_path) + 1);
350 /* Stores in '*un' a sockaddr_un that refers to file 'name'. Stores in
351 * '*un_len' the size of the sockaddr_un.
353 * Returns 0 on success, otherwise a positive errno value. On success,
354 * '*dirfdp' is either -1 or a nonnegative file descriptor that the caller
355 * should close after using '*un' to bind or connect. On failure, '*dirfdp' is
358 make_sockaddr_un(const char *name, struct sockaddr_un *un, socklen_t *un_len,
361 enum { MAX_UN_LEN = sizeof un->sun_path - 1 };
364 if (strlen(name) > MAX_UN_LEN) {
365 static struct vlog_rate_limit rl = VLOG_RATE_LIMIT_INIT(1, 1);
367 if (LINUX_DATAPATH) {
368 /* 'name' is too long to fit in a sockaddr_un, but we have a
369 * workaround for that on Linux: shorten it by opening a file
370 * descriptor for the directory part of the name and indirecting
371 * through /proc/self/fd/<dirfd>/<basename>. */
376 dir = dir_name(name);
377 base = base_name(name);
379 dirfd = open(dir, O_DIRECTORY | O_RDONLY);
386 short_name = xasprintf("/proc/self/fd/%d/%s", dirfd, base);
390 if (strlen(short_name) <= MAX_UN_LEN) {
391 make_sockaddr_un__(short_name, un, un_len);
399 VLOG_WARN_RL(&rl, "Unix socket name %s is longer than maximum "
400 "%d bytes (even shortened)", name, MAX_UN_LEN);
402 /* 'name' is too long and we have no workaround. */
403 VLOG_WARN_RL(&rl, "Unix socket name %s is longer than maximum "
404 "%d bytes", name, MAX_UN_LEN);
409 make_sockaddr_un__(name, un, un_len);
414 /* Binds Unix domain socket 'fd' to a file with permissions 0700. */
416 bind_unix_socket(int fd, struct sockaddr *sun, socklen_t sun_len)
418 /* According to _Unix Network Programming_, umask should affect bind(). */
419 mode_t old_umask = umask(0077);
420 int error = bind(fd, sun, sun_len) ? errno : 0;
425 /* Creates a Unix domain socket in the given 'style' (either SOCK_DGRAM or
426 * SOCK_STREAM) that is bound to '*bind_path' (if 'bind_path' is non-null) and
427 * connected to '*connect_path' (if 'connect_path' is non-null). If 'nonblock'
428 * is true, the socket is made non-blocking.
430 * Returns the socket's fd if successful, otherwise a negative errno value. */
432 make_unix_socket(int style, bool nonblock,
433 const char *bind_path, const char *connect_path)
438 fd = socket(PF_UNIX, style, 0);
443 /* Set nonblocking mode right away, if we want it. This prevents blocking
444 * in connect(), if connect_path != NULL. (In turn, that's a corner case:
445 * it will only happen if style is SOCK_STREAM or SOCK_SEQPACKET, and only
446 * if a backlog of un-accepted connections has built up in the kernel.) */
448 error = set_nonblocking(fd);
455 struct sockaddr_un un;
459 if (unlink(bind_path) && errno != ENOENT) {
460 VLOG_WARN("unlinking \"%s\": %s\n",
461 bind_path, ovs_strerror(errno));
463 fatal_signal_add_file_to_unlink(bind_path);
465 error = make_sockaddr_un(bind_path, &un, &un_len, &dirfd);
467 error = bind_unix_socket(fd, (struct sockaddr *) &un, un_len);
478 struct sockaddr_un un;
482 error = make_sockaddr_un(connect_path, &un, &un_len, &dirfd);
484 && connect(fd, (struct sockaddr*) &un, un_len)
485 && errno != EINPROGRESS) {
499 if (error == EAGAIN) {
503 fatal_signal_unlink_file_now(bind_path);
510 get_unix_name_len(socklen_t sun_len)
512 return (sun_len >= offsetof(struct sockaddr_un, sun_path)
513 ? sun_len - offsetof(struct sockaddr_un, sun_path)
518 guess_netmask(ovs_be32 ip_)
520 uint32_t ip = ntohl(ip_);
521 return ((ip >> 31) == 0 ? htonl(0xff000000) /* Class A */
522 : (ip >> 30) == 2 ? htonl(0xffff0000) /* Class B */
523 : (ip >> 29) == 6 ? htonl(0xffffff00) /* Class C */
524 : htonl(0)); /* ??? */
527 /* Parses 'target', which should be a string in the format "<host>[:<port>]".
528 * <host> is required. If 'default_port' is nonzero then <port> is optional
529 * and defaults to 'default_port'.
531 * On success, returns true and stores the parsed remote address into '*sinp'.
532 * On failure, logs an error, stores zeros into '*sinp', and returns false. */
534 inet_parse_active(const char *target_, uint16_t default_port,
535 struct sockaddr_in *sinp)
537 char *target = xstrdup(target_);
538 char *save_ptr = NULL;
539 const char *host_name;
540 const char *port_string;
544 sinp->sin_family = AF_INET;
545 sinp->sin_port = htons(default_port);
548 host_name = strtok_r(target, ":", &save_ptr);
549 port_string = strtok_r(NULL, ":", &save_ptr);
551 VLOG_ERR("%s: bad peer name format", target_);
555 /* Look up IP, port. */
556 if (lookup_ip(host_name, &sinp->sin_addr)) {
559 if (port_string && atoi(port_string)) {
560 sinp->sin_port = htons(atoi(port_string));
561 } else if (!default_port) {
562 VLOG_ERR("%s: port number must be specified", target_);
570 memset(sinp, 0, sizeof *sinp);
576 /* Opens a non-blocking IPv4 socket of the specified 'style' and connects to
577 * 'target', which should be a string in the format "<host>[:<port>]". <host>
578 * is required. If 'default_port' is nonzero then <port> is optional and
579 * defaults to 'default_port'.
581 * 'style' should be SOCK_STREAM (for TCP) or SOCK_DGRAM (for UDP).
583 * On success, returns 0 (indicating connection complete) or EAGAIN (indicating
584 * connection in progress), in which case the new file descriptor is stored
585 * into '*fdp'. On failure, returns a positive errno value other than EAGAIN
586 * and stores -1 into '*fdp'.
588 * If 'sinp' is non-null, then on success the target address is stored into
591 * 'dscp' becomes the DSCP bits in the IP headers for the new connection. It
592 * should be in the range [0, 63] and will automatically be shifted to the
593 * appropriately place in the IP tos field. */
595 inet_open_active(int style, const char *target, uint16_t default_port,
596 struct sockaddr_in *sinp, int *fdp, uint8_t dscp)
598 struct sockaddr_in sin;
603 if (!inet_parse_active(target, default_port, &sin)) {
604 error = EAFNOSUPPORT;
608 /* Create non-blocking socket. */
609 fd = socket(AF_INET, style, 0);
611 VLOG_ERR("%s: socket: %s", target, ovs_strerror(errno));
615 error = set_nonblocking(fd);
620 /* The dscp bits must be configured before connect() to ensure that the TOS
621 * field is set during the connection establishment. If set after
622 * connect(), the handshake SYN frames will be sent with a TOS of 0. */
623 error = set_dscp(fd, dscp);
625 VLOG_ERR("%s: socket: %s", target, ovs_strerror(error));
630 error = connect(fd, (struct sockaddr *) &sin, sizeof sin) == 0 ? 0 : errno;
631 if (error == EINPROGRESS) {
636 if (!error || error == EAGAIN) {
640 } else if (fd >= 0) {
648 /* Parses 'target', which should be a string in the format "[<port>][:<ip>]":
650 * - If 'default_port' is -1, then <port> is required. Otherwise, if
651 * <port> is omitted, then 'default_port' is used instead.
653 * - If <port> (or 'default_port', if used) is 0, then no port is bound
654 * and the TCP/IP stack will select a port.
656 * - If <ip> is omitted then the IP address is wildcarded.
658 * If successful, stores the address into '*sinp' and returns true; otherwise
659 * zeros '*sinp' and returns false. */
661 inet_parse_passive(const char *target_, int default_port,
662 struct sockaddr_in *sinp)
664 char *target = xstrdup(target_);
665 char *string_ptr = target;
666 const char *host_name;
667 const char *port_string;
671 /* Address defaults. */
672 memset(sinp, 0, sizeof *sinp);
673 sinp->sin_family = AF_INET;
674 sinp->sin_addr.s_addr = htonl(INADDR_ANY);
675 sinp->sin_port = htons(default_port);
677 /* Parse optional port number. */
678 port_string = strsep(&string_ptr, ":");
679 if (port_string && str_to_int(port_string, 10, &port)) {
680 sinp->sin_port = htons(port);
681 } else if (default_port < 0) {
682 VLOG_ERR("%s: port number must be specified", target_);
686 /* Parse optional bind IP. */
687 host_name = strsep(&string_ptr, ":");
688 if (host_name && host_name[0] && lookup_ip(host_name, &sinp->sin_addr)) {
696 memset(sinp, 0, sizeof *sinp);
703 /* Opens a non-blocking IPv4 socket of the specified 'style', binds to
704 * 'target', and listens for incoming connections. Parses 'target' in the same
705 * way was inet_parse_passive().
707 * 'style' should be SOCK_STREAM (for TCP) or SOCK_DGRAM (for UDP).
709 * For TCP, the socket will have SO_REUSEADDR turned on.
711 * On success, returns a non-negative file descriptor. On failure, returns a
712 * negative errno value.
714 * If 'sinp' is non-null, then on success the bound address is stored into
717 * 'dscp' becomes the DSCP bits in the IP headers for the new connection. It
718 * should be in the range [0, 63] and will automatically be shifted to the
719 * appropriately place in the IP tos field. */
721 inet_open_passive(int style, const char *target, int default_port,
722 struct sockaddr_in *sinp, uint8_t dscp)
724 bool kernel_chooses_port;
725 struct sockaddr_in sin;
727 unsigned int yes = 1;
729 if (!inet_parse_passive(target, default_port, &sin)) {
730 return -EAFNOSUPPORT;
733 /* Create non-blocking socket, set SO_REUSEADDR. */
734 fd = socket(AF_INET, style, 0);
737 VLOG_ERR("%s: socket: %s", target, ovs_strerror(error));
740 error = set_nonblocking(fd);
744 if (style == SOCK_STREAM
745 && setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &yes, sizeof yes) < 0) {
747 VLOG_ERR("%s: setsockopt(SO_REUSEADDR): %s",
748 target, ovs_strerror(error));
753 if (bind(fd, (struct sockaddr *) &sin, sizeof sin) < 0) {
755 VLOG_ERR("%s: bind: %s", target, ovs_strerror(error));
759 /* The dscp bits must be configured before connect() to ensure that the TOS
760 * field is set during the connection establishment. If set after
761 * connect(), the handshake SYN frames will be sent with a TOS of 0. */
762 error = set_dscp(fd, dscp);
764 VLOG_ERR("%s: socket: %s", target, ovs_strerror(error));
769 if (style == SOCK_STREAM && listen(fd, 10) < 0) {
771 VLOG_ERR("%s: listen: %s", target, ovs_strerror(error));
775 kernel_chooses_port = sin.sin_port == htons(0);
776 if (sinp || kernel_chooses_port) {
777 socklen_t sin_len = sizeof sin;
778 if (getsockname(fd, (struct sockaddr *) &sin, &sin_len) < 0) {
780 VLOG_ERR("%s: getsockname: %s", target, ovs_strerror(error));
783 if (sin.sin_family != AF_INET || sin_len != sizeof sin) {
784 error = EAFNOSUPPORT;
785 VLOG_ERR("%s: getsockname: invalid socket name", target);
791 if (kernel_chooses_port) {
792 VLOG_INFO("%s: listening on port %"PRIu16,
793 target, ntohs(sin.sin_port));
804 /* Returns a readable and writable fd for /dev/null, if successful, otherwise
805 * a negative errno value. The caller must not close the returned fd (because
806 * the same fd will be handed out to subsequent callers). */
810 static struct ovsthread_once once = OVSTHREAD_ONCE_INITIALIZER;
813 if (ovsthread_once_start(&once)) {
814 null_fd = open("/dev/null", O_RDWR);
817 VLOG_ERR("could not open /dev/null: %s", ovs_strerror(error));
820 ovsthread_once_done(&once);
827 read_fully(int fd, void *p_, size_t size, size_t *bytes_read)
833 ssize_t retval = read(fd, p, size);
835 *bytes_read += retval;
838 } else if (retval == 0) {
840 } else if (errno != EINTR) {
848 write_fully(int fd, const void *p_, size_t size, size_t *bytes_written)
850 const uint8_t *p = p_;
854 ssize_t retval = write(fd, p, size);
856 *bytes_written += retval;
859 } else if (retval == 0) {
860 VLOG_WARN("write returned 0");
862 } else if (errno != EINTR) {
869 /* Given file name 'file_name', fsyncs the directory in which it is contained.
870 * Returns 0 if successful, otherwise a positive errno value. */
872 fsync_parent_dir(const char *file_name)
878 dir = dir_name(file_name);
879 fd = open(dir, O_RDONLY);
882 if (errno == EINVAL || errno == EROFS) {
883 /* This directory does not support synchronization. Not
884 * really an error. */
887 VLOG_ERR("%s: fsync failed (%s)", dir, ovs_strerror(error));
893 VLOG_ERR("%s: open failed (%s)", dir, ovs_strerror(error));
900 /* Obtains the modification time of the file named 'file_name' to the greatest
901 * supported precision. If successful, stores the mtime in '*mtime' and
902 * returns 0. On error, returns a positive errno value and stores zeros in
905 get_mtime(const char *file_name, struct timespec *mtime)
909 if (!stat(file_name, &s)) {
910 mtime->tv_sec = s.st_mtime;
912 #if HAVE_STRUCT_STAT_ST_MTIM_TV_NSEC
913 mtime->tv_nsec = s.st_mtim.tv_nsec;
914 #elif HAVE_STRUCT_STAT_ST_MTIMENSEC
915 mtime->tv_nsec = s.st_mtimensec;
922 mtime->tv_sec = mtime->tv_nsec = 0;
931 VLOG_FATAL("failed to create pipe (%s)", ovs_strerror(errno));
936 xpipe_nonblocking(int fds[2])
939 xset_nonblocking(fds[0]);
940 xset_nonblocking(fds[1]);
944 xsocketpair(int domain, int type, int protocol, int fds[2])
946 if (socketpair(domain, type, protocol, fds)) {
947 VLOG_FATAL("failed to create socketpair (%s)", ovs_strerror(errno));
952 getsockopt_int(int fd, int level, int option, const char *optname, int *valuep)
954 static struct vlog_rate_limit rl = VLOG_RATE_LIMIT_INIT(5, 10);
960 if (getsockopt(fd, level, option, &value, &len)) {
962 VLOG_ERR_RL(&rl, "getsockopt(%s): %s", optname, ovs_strerror(error));
963 } else if (len != sizeof value) {
965 VLOG_ERR_RL(&rl, "getsockopt(%s): value is %u bytes (expected %zu)",
966 optname, (unsigned int) len, sizeof value);
971 *valuep = error ? 0 : value;
976 describe_sockaddr(struct ds *string, int fd,
977 int (*getaddr)(int, struct sockaddr *, socklen_t *))
979 struct sockaddr_storage ss;
980 socklen_t len = sizeof ss;
982 if (!getaddr(fd, (struct sockaddr *) &ss, &len)) {
983 if (ss.ss_family == AF_INET) {
984 struct sockaddr_in sin;
986 memcpy(&sin, &ss, sizeof sin);
987 ds_put_format(string, IP_FMT":%"PRIu16,
988 IP_ARGS(sin.sin_addr.s_addr), ntohs(sin.sin_port));
989 } else if (ss.ss_family == AF_UNIX) {
990 struct sockaddr_un sun;
994 memcpy(&sun, &ss, sizeof sun);
995 maxlen = len - offsetof(struct sockaddr_un, sun_path);
996 null = memchr(sun.sun_path, '\0', maxlen);
997 ds_put_buffer(string, sun.sun_path,
998 null ? null - sun.sun_path : maxlen);
1001 else if (ss.ss_family == AF_NETLINK) {
1004 /* SO_PROTOCOL was introduced in 2.6.32. Support it regardless of the version
1005 * of the Linux kernel headers in use at build time. */
1007 #define SO_PROTOCOL 38
1010 if (!getsockopt_int(fd, SOL_SOCKET, SO_PROTOCOL, "SO_PROTOCOL",
1014 ds_put_cstr(string, "NETLINK_ROUTE");
1017 case NETLINK_GENERIC:
1018 ds_put_cstr(string, "NETLINK_GENERIC");
1022 ds_put_format(string, "AF_NETLINK family %d", protocol);
1026 ds_put_cstr(string, "AF_NETLINK");
1030 #if AF_PACKET && LINUX_DATAPATH
1031 else if (ss.ss_family == AF_PACKET) {
1032 struct sockaddr_ll sll;
1034 memcpy(&sll, &ss, sizeof sll);
1035 ds_put_cstr(string, "AF_PACKET");
1036 if (sll.sll_ifindex) {
1037 char name[IFNAMSIZ];
1039 if (if_indextoname(sll.sll_ifindex, name)) {
1040 ds_put_format(string, "(%s)", name);
1042 ds_put_format(string, "(ifindex=%d)", sll.sll_ifindex);
1045 if (sll.sll_protocol) {
1046 ds_put_format(string, "(protocol=0x%"PRIu16")",
1047 ntohs(sll.sll_protocol));
1051 else if (ss.ss_family == AF_UNSPEC) {
1052 ds_put_cstr(string, "AF_UNSPEC");
1054 ds_put_format(string, "AF_%d", (int) ss.ss_family);
1060 #ifdef LINUX_DATAPATH
1062 put_fd_filename(struct ds *string, int fd)
1068 linkname = xasprintf("/proc/self/fd/%d", fd);
1069 n = readlink(linkname, buf, sizeof buf);
1071 ds_put_char(string, ' ');
1072 ds_put_buffer(string, buf, n);
1073 if (n > sizeof buf) {
1074 ds_put_cstr(string, "...");
1081 /* Returns a malloc()'d string describing 'fd', for use in logging. */
1089 if (fstat(fd, &s)) {
1090 ds_put_format(&string, "fstat failed (%s)", ovs_strerror(errno));
1091 } else if (S_ISSOCK(s.st_mode)) {
1092 describe_sockaddr(&string, fd, getsockname);
1093 ds_put_cstr(&string, "<->");
1094 describe_sockaddr(&string, fd, getpeername);
1096 ds_put_cstr(&string, (isatty(fd) ? "tty"
1097 : S_ISDIR(s.st_mode) ? "directory"
1098 : S_ISCHR(s.st_mode) ? "character device"
1099 : S_ISBLK(s.st_mode) ? "block device"
1100 : S_ISREG(s.st_mode) ? "file"
1101 : S_ISFIFO(s.st_mode) ? "FIFO"
1102 : S_ISLNK(s.st_mode) ? "symbolic link"
1104 #ifdef LINUX_DATAPATH
1105 put_fd_filename(&string, fd);
1108 return ds_steal_cstr(&string);
1111 /* Returns the total of the 'iov_len' members of the 'n_iovs' in 'iovs'.
1112 * The caller must ensure that the total does not exceed SIZE_MAX. */
1114 iovec_len(const struct iovec iovs[], size_t n_iovs)
1119 for (i = 0; i < n_iovs; i++) {
1120 len += iovs[i].iov_len;
1125 /* Returns true if all of the 'n_iovs' iovecs in 'iovs' have length zero. */
1127 iovec_is_empty(const struct iovec iovs[], size_t n_iovs)
1131 for (i = 0; i < n_iovs; i++) {
1132 if (iovs[i].iov_len) {
1139 /* Sends the 'n_iovs' iovecs of data in 'iovs' and the 'n_fds' file descriptors
1140 * in 'fds' on Unix domain socket 'sock'. Returns the number of bytes
1141 * successfully sent or -1 if an error occurred. On error, sets errno
1144 send_iovec_and_fds(int sock,
1145 const struct iovec *iovs, size_t n_iovs,
1146 const int fds[], size_t n_fds)
1148 ovs_assert(sock >= 0);
1152 char control[CMSG_SPACE(SOUTIL_MAX_FDS * sizeof *fds)];
1156 ovs_assert(!iovec_is_empty(iovs, n_iovs));
1157 ovs_assert(n_fds <= SOUTIL_MAX_FDS);
1159 memset(&cmsg, 0, sizeof cmsg);
1160 cmsg.cm.cmsg_len = CMSG_LEN(n_fds * sizeof *fds);
1161 cmsg.cm.cmsg_level = SOL_SOCKET;
1162 cmsg.cm.cmsg_type = SCM_RIGHTS;
1163 memcpy(CMSG_DATA(&cmsg.cm), fds, n_fds * sizeof *fds);
1165 msg.msg_name = NULL;
1166 msg.msg_namelen = 0;
1167 msg.msg_iov = CONST_CAST(struct iovec *, iovs);
1168 msg.msg_iovlen = n_iovs;
1169 msg.msg_control = &cmsg.cm;
1170 msg.msg_controllen = CMSG_SPACE(n_fds * sizeof *fds);
1173 return sendmsg(sock, &msg, 0);
1175 return writev(sock, iovs, n_iovs);
1179 /* Sends the 'n_iovs' iovecs of data in 'iovs' and the 'n_fds' file descriptors
1180 * in 'fds' on Unix domain socket 'sock'. If 'skip_bytes' is nonzero, then the
1181 * first 'skip_bytes' of data in the iovecs are not sent, and none of the file
1182 * descriptors are sent. The function continues to retry sending until an
1183 * error (other than EINTR) occurs or all the data and fds are sent.
1185 * Returns 0 if all the data and fds were successfully sent, otherwise a
1186 * positive errno value. Regardless of success, stores the number of bytes
1187 * sent (always at least 'skip_bytes') in '*bytes_sent'. (If at least one byte
1188 * is sent, then all the fds have been sent.)
1190 * 'skip_bytes' must be less than or equal to iovec_len(iovs, n_iovs). */
1192 send_iovec_and_fds_fully(int sock,
1193 const struct iovec iovs[], size_t n_iovs,
1194 const int fds[], size_t n_fds,
1195 size_t skip_bytes, size_t *bytes_sent)
1198 while (n_iovs > 0) {
1202 retval = skip_bytes;
1204 } else if (!*bytes_sent) {
1205 retval = send_iovec_and_fds(sock, iovs, n_iovs, fds, n_fds);
1207 retval = writev(sock, iovs, n_iovs);
1211 *bytes_sent += retval;
1212 while (retval > 0) {
1213 const uint8_t *base = iovs->iov_base;
1214 size_t len = iovs->iov_len;
1220 error = write_fully(sock, base + retval, len - retval,
1222 *bytes_sent += sent;
1232 } else if (retval == 0) {
1233 if (iovec_is_empty(iovs, n_iovs)) {
1236 VLOG_WARN("send returned 0");
1238 } else if (errno != EINTR) {
1246 /* Sends the 'n_iovs' iovecs of data in 'iovs' and the 'n_fds' file descriptors
1247 * in 'fds' on Unix domain socket 'sock'. The function continues to retry
1248 * sending until an error (other than EAGAIN or EINTR) occurs or all the data
1249 * and fds are sent. Upon EAGAIN, the function blocks until the socket is
1250 * ready for more data.
1252 * Returns 0 if all the data and fds were successfully sent, otherwise a
1253 * positive errno value. */
1255 send_iovec_and_fds_fully_block(int sock,
1256 const struct iovec iovs[], size_t n_iovs,
1257 const int fds[], size_t n_fds)
1264 error = send_iovec_and_fds_fully(sock, iovs, n_iovs,
1265 fds, n_fds, sent, &sent);
1266 if (error != EAGAIN) {
1269 poll_fd_wait(sock, POLLOUT);
1274 /* Attempts to receive from Unix domain socket 'sock' up to 'size' bytes of
1275 * data into 'data' and up to SOUTIL_MAX_FDS file descriptors into 'fds'.
1277 * - Upon success, returns the number of bytes of data copied into 'data'
1278 * and stores the number of received file descriptors into '*n_fdsp'.
1280 * - On failure, returns a negative errno value and stores 0 in
1283 * - On EOF, returns 0 and stores 0 in '*n_fdsp'. */
1285 recv_data_and_fds(int sock,
1286 void *data, size_t size,
1287 int fds[SOUTIL_MAX_FDS], size_t *n_fdsp)
1291 char control[CMSG_SPACE(SOUTIL_MAX_FDS * sizeof *fds)];
1303 iov.iov_base = data;
1306 msg.msg_name = NULL;
1307 msg.msg_namelen = 0;
1310 msg.msg_control = &cmsg.cm;
1311 msg.msg_controllen = sizeof cmsg.control;
1314 retval = recvmsg(sock, &msg, 0);
1315 } while (retval < 0 && errno == EINTR);
1317 return retval < 0 ? -errno : 0;
1320 for (p = CMSG_FIRSTHDR(&msg); p; p = CMSG_NXTHDR(&msg, p)) {
1321 if (p->cmsg_level != SOL_SOCKET || p->cmsg_type != SCM_RIGHTS) {
1322 VLOG_ERR("unexpected control message %d:%d",
1323 p->cmsg_level, p->cmsg_type);
1325 } else if (*n_fdsp) {
1326 VLOG_ERR("multiple SCM_RIGHTS received");
1329 size_t n_fds = (p->cmsg_len - CMSG_LEN(0)) / sizeof *fds;
1330 const int *fds_data = ALIGNED_CAST(const int *, CMSG_DATA(p));
1332 ovs_assert(n_fds > 0);
1333 if (n_fds > SOUTIL_MAX_FDS) {
1334 VLOG_ERR("%zu fds received but only %d supported",
1335 n_fds, SOUTIL_MAX_FDS);
1336 for (i = 0; i < n_fds; i++) {
1343 memcpy(fds, fds_data, n_fds * sizeof *fds);
1350 for (i = 0; i < *n_fdsp; i++) {