-/* Copyright (C) 2007 Board of Trustees, Leland Stanford Jr. University.
- *
- * Permission is hereby granted, free of charge, to any person obtaining a copy
- * of this software and associated documentation files (the "Software"), to
- * deal in the Software without restriction, including without limitation the
- * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
- * sell copies of the Software, and to permit persons to whom the Software is
- * furnished to do so, subject to the following conditions:
- *
- * The above copyright notice and this permission notice shall be included in
- * all copies or substantial portions of the Software.
- *
- * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
- * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
- * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
- * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
- * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
- * IN THE SOFTWARE.
+/* Copyright (c) 2008 The Board of Trustees of The Leland Stanford
+ * Junior University
+ *
+ * We are making the OpenFlow specification and associated documentation
+ * (Software) available for public use and benefit with the expectation
+ * that others will use, modify and enhance the Software and contribute
+ * those enhancements back to the community. However, since we would
+ * like to make the Software available for broadest use, with as few
+ * restrictions as possible permission is hereby granted, free of
+ * charge, to any person obtaining a copy of this Software to deal in
+ * the Software under the copyrights without restriction, including
+ * without limitation the rights to use, copy, modify, merge, publish,
+ * distribute, sublicense, and/or sell copies of the Software, and to
+ * permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be
+ * included in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
+ * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
+ * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ *
+ * The name and trademarks of copyright holder(s) may NOT be used in
+ * advertising or publicity pertaining to the Software or any
+ * derivatives without specific, written prior permission.
*/
+#include <config.h>
#include "socket-util.h"
#include <arpa/inet.h>
#include <errno.h>
#include <fcntl.h>
#include <netdb.h>
#include <poll.h>
+#include <stddef.h>
#include <stdio.h>
#include <string.h>
+#include <sys/resource.h>
+#include <sys/un.h>
+#include <unistd.h>
+#include "fatal-signal.h"
+#include "util.h"
#include "vlog.h"
#define THIS_MODULE VLM_socket_util
}
}
+/* Returns the maximum valid FD value, plus 1. */
+int
+get_max_fds(void)
+{
+ static int max_fds = -1;
+ if (max_fds < 0) {
+ struct rlimit r;
+ if (!getrlimit(RLIMIT_NOFILE, &r)
+ && r.rlim_cur != RLIM_INFINITY
+ && r.rlim_cur != RLIM_SAVED_MAX
+ && r.rlim_cur != RLIM_SAVED_CUR) {
+ max_fds = r.rlim_cur;
+ } else {
+ VLOG_WARN("failed to obtain fd limit, defaulting to 1024");
+ max_fds = 1024;
+ }
+ }
+ return max_fds;
+}
+
/* Translates 'host_name', which may be a DNS name or an IP address, into a
* numeric IP address in '*addr'. Returns 0 if successful, otherwise a
* positive errno value. */
if (!inet_aton(host_name, addr)) {
struct hostent *he = gethostbyname(host_name);
if (he == NULL) {
- VLOG_ERR("gethostbyname(%s): %s", host_name,
- (h_errno == HOST_NOT_FOUND ? "host not found"
- : h_errno == TRY_AGAIN ? "try again"
- : h_errno == NO_RECOVERY ? "non-recoverable error"
- : h_errno == NO_ADDRESS ? "no address"
- : "unknown error"));
+ struct vlog_rate_limit rl = VLOG_RATE_LIMIT_INIT(1, 5);
+ VLOG_ERR_RL(&rl, "gethostbyname(%s): %s", host_name,
+ (h_errno == HOST_NOT_FOUND ? "host not found"
+ : h_errno == TRY_AGAIN ? "try again"
+ : h_errno == NO_RECOVERY ? "non-recoverable error"
+ : h_errno == NO_ADDRESS ? "no address"
+ : "unknown error"));
return ENOENT;
}
addr->s_addr = *(uint32_t *) he->h_addr;
int error;
socklen_t len = sizeof(error);
if (getsockopt(fd, SOL_SOCKET, SO_ERROR, &error, &len) < 0) {
+ struct vlog_rate_limit rl = VLOG_RATE_LIMIT_INIT(5, 10);
error = errno;
- VLOG_ERR("getsockopt(SO_ERROR): %s", strerror(error));
+ VLOG_ERR_RL(&rl, "getsockopt(SO_ERROR): %s", strerror(error));
}
return error;
}
if (retval == 1) {
return get_socket_error(fd);
} else if (retval < 0) {
- VLOG_ERR("poll: %s", strerror(errno));
+ static struct vlog_rate_limit rl = VLOG_RATE_LIMIT_INIT(5, 10);
+ VLOG_ERR_RL(&rl, "poll: %s", strerror(errno));
return errno;
} else {
return EAGAIN;
}
}
+
+/* Drain all the data currently in the receive queue of a datagram socket (and
+ * possibly additional data). There is no way to know how many packets are in
+ * the receive queue, but we do know that the total number of bytes queued does
+ * not exceed the receive buffer size, so we pull packets until none are left
+ * or we've read that many bytes. */
+int
+drain_rcvbuf(int fd)
+{
+ socklen_t rcvbuf_len;
+ size_t rcvbuf;
+
+ rcvbuf_len = sizeof rcvbuf;
+ if (getsockopt(fd, SOL_SOCKET, SO_RCVBUF, &rcvbuf, &rcvbuf_len) < 0) {
+ static struct vlog_rate_limit rl = VLOG_RATE_LIMIT_INIT(5, 10);
+ VLOG_ERR_RL(&rl, "getsockopt(SO_RCVBUF) failed: %s", strerror(errno));
+ return errno;
+ }
+ while (rcvbuf > 0) {
+ /* In Linux, specifying MSG_TRUNC in the flags argument causes the
+ * datagram length to be returned, even if that is longer than the
+ * buffer provided. Thus, we can use a 1-byte buffer to discard the
+ * incoming datagram and still be able to account how many bytes were
+ * removed from the receive buffer.
+ *
+ * On other Unix-like OSes, MSG_TRUNC has no effect in the flags
+ * argument. */
+#ifdef __linux__
+#define BUFFER_SIZE 1
+#else
+#define BUFFER_SIZE 2048
+#endif
+ char buffer[BUFFER_SIZE];
+ ssize_t n_bytes = recv(fd, buffer, sizeof buffer,
+ MSG_TRUNC | MSG_DONTWAIT);
+ if (n_bytes <= 0 || n_bytes >= rcvbuf) {
+ break;
+ }
+ rcvbuf -= n_bytes;
+ }
+ return 0;
+}
+
+/* Reads and discards up to 'n' datagrams from 'fd', stopping as soon as no
+ * more data can be immediately read. ('fd' should therefore be in
+ * non-blocking mode.)*/
+void
+drain_fd(int fd, size_t n_packets)
+{
+ for (; n_packets > 0; n_packets--) {
+ /* 'buffer' only needs to be 1 byte long in most circumstances. This
+ * size is defensive against the possibility that we someday want to
+ * use a Linux tap device without TUN_NO_PI, in which case a buffer
+ * smaller than sizeof(struct tun_pi) will give EINVAL on read. */
+ char buffer[128];
+ if (read(fd, buffer, sizeof buffer) <= 0) {
+ break;
+ }
+ }
+}
+
+/* Stores in '*un' a sockaddr_un that refers to file 'name'. Stores in
+ * '*un_len' the size of the sockaddr_un. */
+static void
+make_sockaddr_un(const char *name, struct sockaddr_un* un, socklen_t *un_len)
+{
+ un->sun_family = AF_UNIX;
+ strncpy(un->sun_path, name, sizeof un->sun_path);
+ un->sun_path[sizeof un->sun_path - 1] = '\0';
+ *un_len = (offsetof(struct sockaddr_un, sun_path)
+ + strlen (un->sun_path) + 1);
+}
+
+/* Creates a Unix domain socket in the given 'style' (either SOCK_DGRAM or
+ * SOCK_STREAM) that is bound to '*bind_path' (if 'bind_path' is non-null) and
+ * connected to '*connect_path' (if 'connect_path' is non-null). If 'nonblock'
+ * is true, the socket is made non-blocking. If 'passcred' is true, the socket
+ * is configured to receive SCM_CREDENTIALS control messages.
+ *
+ * Returns the socket's fd if successful, otherwise a negative errno value. */
+int
+make_unix_socket(int style, bool nonblock, bool passcred UNUSED,
+ const char *bind_path, const char *connect_path)
+{
+ int error;
+ int fd;
+
+ fd = socket(PF_UNIX, style, 0);
+ if (fd < 0) {
+ return -errno;
+ }
+
+ /* Set nonblocking mode right away, if we want it. This prevents blocking
+ * in connect(), if connect_path != NULL. (In turn, that's a corner case:
+ * it will only happen if style is SOCK_STREAM or SOCK_SEQPACKET, and only
+ * if a backlog of un-accepted connections has built up in the kernel.) */
+ if (nonblock) {
+ int flags = fcntl(fd, F_GETFL, 0);
+ if (flags == -1) {
+ goto error;
+ }
+ if (fcntl(fd, F_SETFL, flags | O_NONBLOCK) == -1) {
+ goto error;
+ }
+ }
+
+ if (bind_path) {
+ struct sockaddr_un un;
+ socklen_t un_len;
+ make_sockaddr_un(bind_path, &un, &un_len);
+ if (unlink(un.sun_path) && errno != ENOENT) {
+ VLOG_WARN("unlinking \"%s\": %s\n", un.sun_path, strerror(errno));
+ }
+ fatal_signal_add_file_to_unlink(bind_path);
+ if (bind(fd, (struct sockaddr*) &un, un_len)
+ || fchmod(fd, S_IRWXU)) {
+ goto error;
+ }
+ }
+
+ if (connect_path) {
+ struct sockaddr_un un;
+ socklen_t un_len;
+ make_sockaddr_un(connect_path, &un, &un_len);
+ if (connect(fd, (struct sockaddr*) &un, un_len)
+ && errno != EINPROGRESS) {
+ goto error;
+ }
+ }
+
+#ifdef SCM_CREDENTIALS
+ if (passcred) {
+ int enable = 1;
+ if (setsockopt(fd, SOL_SOCKET, SO_PASSCRED, &enable, sizeof(enable))) {
+ goto error;
+ }
+ }
+#endif
+
+ return fd;
+
+error:
+ if (bind_path) {
+ fatal_signal_remove_file_to_unlink(bind_path);
+ }
+ error = errno;
+ close(fd);
+ return -error;
+}
+
+int
+get_unix_name_len(socklen_t sun_len)
+{
+ return (sun_len >= offsetof(struct sockaddr_un, sun_path)
+ ? sun_len - offsetof(struct sockaddr_un, sun_path)
+ : 0);
+}
git://git.onelab.eu / sliver-openvswitch.git / blobdiff