X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=lib%2Fsocket-util.c;h=8fa663ad75fc3784c8560390f2ddcb4422343f4a;hb=666a53b7f71b605b33737b45a71fafcb5aa6c694;hp=dac35944031091482e8e785671c23616c28373e5;hpb=a9111b60153ba0a726a1711f2b7969d2691fbb0f;p=sliver-openvswitch.git diff --git a/lib/socket-util.c b/lib/socket-util.c index dac359440..8fa663ad7 100644 --- a/lib/socket-util.c +++ b/lib/socket-util.c @@ -1,32 +1,50 @@ -/* 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 #include "socket-util.h" #include #include #include #include #include +#include #include #include +#include +#include +#include "fatal-signal.h" +#include "util.h" #include "vlog.h" #define THIS_MODULE VLM_socket_util @@ -59,12 +77,13 @@ lookup_ip(const char *host_name, struct in_addr *addr) 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; @@ -80,8 +99,9 @@ get_socket_error(int fd) 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; } @@ -100,9 +120,137 @@ check_connection_completion(int fd) 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; +} + +/* 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; + } + + 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; +}