X-Git-Url: http://git.cascardo.eti.br/?a=blobdiff_plain;f=lib%2Fsocket-util.c;h=bb48ade9b4a197b1c393700b0dbb1c71038b51b1;hb=34582733d9aad82bba60f4bf986b62d58412502a;hp=c436724cd501f44f701bb53e33046af20ffaddeb;hpb=13f2ef9709fbe24b56540ddc5db62c1098b4190f;p=cascardo%2Fovs.git diff --git a/lib/socket-util.c b/lib/socket-util.c index c436724cd..bb48ade9b 100644 --- a/lib/socket-util.c +++ b/lib/socket-util.c @@ -1,5 +1,5 @@ /* - * Copyright (c) 2008, 2009, 2010, 2011 Nicira Networks. + * Copyright (c) 2008, 2009, 2010, 2011, 2012, 2013 Nicira, Inc. * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. @@ -26,17 +26,20 @@ #include #include #include +#include #include #include #include +#include #include #include #include "dynamic-string.h" #include "fatal-signal.h" #include "packets.h" +#include "poll-loop.h" #include "util.h" #include "vlog.h" -#if AF_PACKET && __linux__ +#if AF_PACKET && LINUX_DATAPATH #include #endif #ifdef HAVE_NETLINK @@ -48,17 +51,22 @@ VLOG_DEFINE_THIS_MODULE(socket_util); /* #ifdefs make it a pain to maintain code: you have to try to build both ways. * Thus, this file compiles all of the code regardless of the target, by - * writing "if (LINUX)" instead of "#ifdef __linux__". */ -#ifdef __linux__ -#define LINUX 1 -#else -#define LINUX 0 + * writing "if (LINUX_DATAPATH)" instead of "#ifdef __linux__". */ +#ifndef LINUX_DATAPATH +#define LINUX_DATAPATH 0 #endif #ifndef O_DIRECTORY #define O_DIRECTORY 0 #endif +/* Maximum length of the sun_path member in a struct sockaddr_un, excluding + * space for a null terminator. */ +#define MAX_UN_LEN (sizeof(((struct sockaddr_un *) 0)->sun_path) - 1) + +static int getsockopt_int(int fd, int level, int option, const char *optname, + int *valuep); + /* Sets 'fd' to non-blocking mode. Returns 0 if successful, otherwise a * positive errno value. */ int @@ -69,13 +77,38 @@ set_nonblocking(int fd) if (fcntl(fd, F_SETFL, flags | O_NONBLOCK) != -1) { return 0; } else { - VLOG_ERR("fcntl(F_SETFL) failed: %s", strerror(errno)); + VLOG_ERR("fcntl(F_SETFL) failed: %s", ovs_strerror(errno)); return errno; } } else { - VLOG_ERR("fcntl(F_GETFL) failed: %s", strerror(errno)); + VLOG_ERR("fcntl(F_GETFL) failed: %s", ovs_strerror(errno)); + return errno; + } +} + +void +xset_nonblocking(int fd) +{ + if (set_nonblocking(fd)) { + exit(EXIT_FAILURE); + } +} + +int +set_dscp(int fd, uint8_t dscp) +{ + int val; + + if (dscp > 63) { + return EINVAL; + } + + val = dscp << 2; + if (setsockopt(fd, IPPROTO_IP, IP_TOS, &val, sizeof val)) { return errno; } + + return 0; } static bool @@ -104,8 +137,10 @@ rlim_is_finite(rlim_t limit) int get_max_fds(void) { - static int max_fds = -1; - if (max_fds < 0) { + static struct ovsthread_once once = OVSTHREAD_ONCE_INITIALIZER; + static int max_fds; + + if (ovsthread_once_start(&once)) { struct rlimit r; if (!getrlimit(RLIMIT_NOFILE, &r) && rlim_is_finite(r.rlim_cur)) { max_fds = r.rlim_cur; @@ -113,7 +148,9 @@ get_max_fds(void) VLOG_WARN("failed to obtain fd limit, defaulting to 1024"); max_fds = 1024; } + ovsthread_once_done(&once); } + return max_fds; } @@ -150,50 +187,68 @@ lookup_ipv6(const char *host_name, struct in6_addr *addr) * successful, otherwise a positive errno value. * * Most Open vSwitch code should not use this because it causes deadlocks: - * gethostbyname() sends out a DNS request but that starts a new flow for which + * getaddrinfo() sends out a DNS request but that starts a new flow for which * OVS must set up a flow, but it can't because it's waiting for a DNS reply. - * The synchronous lookup also delays other activty. (Of course we can solve + * The synchronous lookup also delays other activity. (Of course we can solve * this but it doesn't seem worthwhile quite yet.) */ int lookup_hostname(const char *host_name, struct in_addr *addr) { - struct hostent *h; + struct addrinfo *result; + struct addrinfo hints; if (inet_aton(host_name, addr)) { return 0; } - h = gethostbyname(host_name); - if (h) { - *addr = *(struct in_addr *) h->h_addr; + memset(&hints, 0, sizeof hints); + hints.ai_family = AF_INET; + + switch (getaddrinfo(host_name, NULL, &hints, &result)) { + case 0: + *addr = ALIGNED_CAST(struct sockaddr_in *, + result->ai_addr)->sin_addr; + freeaddrinfo(result); return 0; - } - return (h_errno == HOST_NOT_FOUND ? ENOENT - : h_errno == TRY_AGAIN ? EAGAIN - : h_errno == NO_RECOVERY ? EIO - : h_errno == NO_ADDRESS ? ENXIO - : EINVAL); -} +#ifdef EAI_ADDRFAMILY + case EAI_ADDRFAMILY: +#endif + case EAI_NONAME: + case EAI_SERVICE: + return ENOENT; -/* Returns the error condition associated with socket 'fd' and resets the - * socket's error status. */ -int -get_socket_error(int fd) -{ - int error; - socklen_t len = sizeof(error); - if (getsockopt(fd, SOL_SOCKET, SO_ERROR, &error, &len) < 0) { - static struct vlog_rate_limit rl = VLOG_RATE_LIMIT_INIT(5, 10); - error = errno; - VLOG_ERR_RL(&rl, "getsockopt(SO_ERROR): %s", strerror(error)); + case EAI_AGAIN: + return EAGAIN; + + case EAI_BADFLAGS: + case EAI_FAMILY: + case EAI_SOCKTYPE: + return EINVAL; + + case EAI_FAIL: + return EIO; + + case EAI_MEMORY: + return ENOMEM; + +#ifdef EAI_NODATA + case EAI_NODATA: + return ENXIO; +#endif + + case EAI_SYSTEM: + return errno; + + default: + return EPROTO; } - return error; } int check_connection_completion(int fd) { + static struct vlog_rate_limit rl = VLOG_RATE_LIMIT_INIT(5, 10); struct pollfd pfd; int retval; @@ -203,10 +258,18 @@ check_connection_completion(int fd) retval = poll(&pfd, 1, 0); } while (retval < 0 && errno == EINTR); if (retval == 1) { - return get_socket_error(fd); + if (pfd.revents & POLLERR) { + ssize_t n = send(fd, "", 1, MSG_DONTWAIT); + if (n < 0) { + return errno; + } else { + VLOG_ERR_RL(&rl, "poll return POLLERR but send succeeded"); + return EPROTO; + } + } + return 0; } else if (retval < 0) { - static struct vlog_rate_limit rl = VLOG_RATE_LIMIT_INIT(5, 10); - VLOG_ERR_RL(&rl, "poll: %s", strerror(errno)); + VLOG_ERR_RL(&rl, "poll: %s", ovs_strerror(errno)); return errno; } else { return EAGAIN; @@ -221,15 +284,13 @@ check_connection_completion(int fd) int drain_rcvbuf(int fd) { - socklen_t rcvbuf_len; - size_t rcvbuf; + int 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; + rcvbuf = get_socket_rcvbuf(fd); + if (rcvbuf < 0) { + return -rcvbuf; } + 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 @@ -239,7 +300,7 @@ drain_rcvbuf(int fd) * * On other Unix-like OSes, MSG_TRUNC has no effect in the flags * argument. */ - char buffer[LINUX ? 1 : 2048]; + char buffer[LINUX_DATAPATH ? 1 : 2048]; ssize_t n_bytes = recv(fd, buffer, sizeof buffer, MSG_TRUNC | MSG_DONTWAIT); if (n_bytes <= 0 || n_bytes >= rcvbuf) { @@ -250,6 +311,18 @@ drain_rcvbuf(int fd) return 0; } +/* Returns the size of socket 'sock''s receive buffer (SO_RCVBUF), or a + * negative errno value if an error occurs. */ +int +get_socket_rcvbuf(int sock) +{ + int rcvbuf; + int error; + + error = getsockopt_int(sock, SOL_SOCKET, SO_RCVBUF, "SO_RCVBUF", &rcvbuf); + return error ? -error : rcvbuf; +} + /* 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.)*/ @@ -268,78 +341,161 @@ drain_fd(int fd, size_t n_packets) } } -/* 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) +/* Attempts to shorten 'name' by opening a file descriptor for the directory + * part of the name and indirecting through /proc/self/fd//. + * On systems with Linux-like /proc, this works as long as isn't too + * long. + * + * On success, returns 0 and stores the short name in 'short_name' and a + * directory file descriptor to eventually be closed in '*dirfpd'. */ +static int +shorten_name_via_proc(const char *name, char short_name[MAX_UN_LEN + 1], + int *dirfdp) { - un->sun_family = AF_UNIX; - ovs_strzcpy(un->sun_path, name, sizeof un->sun_path); - *un_len = (offsetof(struct sockaddr_un, sun_path) - + strlen (un->sun_path) + 1); + char *dir, *base; + int dirfd; + int len; + + if (!LINUX_DATAPATH) { + return ENAMETOOLONG; + } + + dir = dir_name(name); + dirfd = open(dir, O_DIRECTORY | O_RDONLY); + if (dirfd < 0) { + static struct vlog_rate_limit rl = VLOG_RATE_LIMIT_INIT(1, 1); + int error = errno; + + VLOG_WARN_RL(&rl, "%s: open failed (%s)", dir, ovs_strerror(error)); + free(dir); + + return error; + } + free(dir); + + base = base_name(name); + len = snprintf(short_name, MAX_UN_LEN + 1, + "/proc/self/fd/%d/%s", dirfd, base); + free(base); + + if (len >= 0 && len <= MAX_UN_LEN) { + *dirfdp = dirfd; + return 0; + } else { + close(dirfd); + return ENAMETOOLONG; + } +} + +/* Attempts to shorten 'name' by creating a symlink for the directory part of + * the name and indirecting through /. This works on + * systems that support symlinks, as long as isn't too long. + * + * On success, returns 0 and stores the short name in 'short_name' and the + * symbolic link to eventually delete in 'linkname'. */ +static int +shorten_name_via_symlink(const char *name, char short_name[MAX_UN_LEN + 1], + char linkname[MAX_UN_LEN + 1]) +{ + char *abs, *dir, *base; + const char *tmpdir; + int error; + int i; + + abs = abs_file_name(NULL, name); + dir = dir_name(abs); + base = base_name(abs); + free(abs); + + tmpdir = getenv("TMPDIR"); + if (tmpdir == NULL) { + tmpdir = "/tmp"; + } + + for (i = 0; i < 1000; i++) { + int len; + + len = snprintf(linkname, MAX_UN_LEN + 1, + "%s/ovs-un-c-%"PRIu32, tmpdir, random_uint32()); + error = (len < 0 || len > MAX_UN_LEN ? ENAMETOOLONG + : symlink(dir, linkname) ? errno + : 0); + if (error != EEXIST) { + break; + } + } + + if (!error) { + int len; + + fatal_signal_add_file_to_unlink(linkname); + + len = snprintf(short_name, MAX_UN_LEN + 1, "%s/%s", linkname, base); + if (len < 0 || len > MAX_UN_LEN) { + fatal_signal_unlink_file_now(linkname); + error = ENAMETOOLONG; + } + } + + if (error) { + linkname[0] = '\0'; + } + free(dir); + free(base); + + return error; } /* Stores in '*un' a sockaddr_un that refers to file 'name'. Stores in * '*un_len' the size of the sockaddr_un. * - * Returns 0 on success, otherwise a positive errno value. On success, - * '*dirfdp' is either -1 or a nonnegative file descriptor that the caller - * should close after using '*un' to bind or connect. On failure, '*dirfdp' is - * -1. */ + * Returns 0 on success, otherwise a positive errno value. + * + * Uses '*dirfdp' and 'linkname' to store references to data when the caller no + * longer needs to use 'un'. On success, freeing these references with + * free_sockaddr_un() is mandatory to avoid a leak; on failure, freeing them is + * unnecessary but harmless. */ static int make_sockaddr_un(const char *name, struct sockaddr_un *un, socklen_t *un_len, - int *dirfdp) + int *dirfdp, char linkname[MAX_UN_LEN + 1]) { - enum { MAX_UN_LEN = sizeof un->sun_path - 1 }; + char short_name[MAX_UN_LEN + 1]; *dirfdp = -1; + linkname[0] = '\0'; if (strlen(name) > MAX_UN_LEN) { - static struct vlog_rate_limit rl = VLOG_RATE_LIMIT_INIT(1, 1); - - if (LINUX) { - /* 'name' is too long to fit in a sockaddr_un, but we have a - * workaround for that on Linux: shorten it by opening a file - * descriptor for the directory part of the name and indirecting - * through /proc/self/fd//. */ - char *dir, *base; - char *short_name; - int dirfd; - - dir = dir_name(name); - base = base_name(name); - - dirfd = open(dir, O_DIRECTORY | O_RDONLY); - if (dirfd < 0) { - free(base); - free(dir); - return errno; - } - - short_name = xasprintf("/proc/self/fd/%d/%s", dirfd, base); - free(dir); - free(base); - - if (strlen(short_name) <= MAX_UN_LEN) { - make_sockaddr_un__(short_name, un, un_len); - free(short_name); - *dirfdp = dirfd; - return 0; - } - free(short_name); - close(dirfd); + /* 'name' is too long to fit in a sockaddr_un. Try a workaround. */ + int error = shorten_name_via_proc(name, short_name, dirfdp); + if (error == ENAMETOOLONG) { + error = shorten_name_via_symlink(name, short_name, linkname); + } + if (error) { + static struct vlog_rate_limit rl = VLOG_RATE_LIMIT_INIT(1, 1); VLOG_WARN_RL(&rl, "Unix socket name %s is longer than maximum " - "%d bytes (even shortened)", name, MAX_UN_LEN); - } else { - /* 'name' is too long and we have no workaround. */ - VLOG_WARN_RL(&rl, "Unix socket name %s is longer than maximum " - "%d bytes", name, MAX_UN_LEN); + "%"PRIuSIZE" bytes", name, MAX_UN_LEN); + return error; } - return ENAMETOOLONG; - } else { - make_sockaddr_un__(name, un, un_len); - return 0; + name = short_name; + } + + un->sun_family = AF_UNIX; + ovs_strzcpy(un->sun_path, name, sizeof un->sun_path); + *un_len = (offsetof(struct sockaddr_un, sun_path) + + strlen (un->sun_path) + 1); + return 0; +} + +/* Clean up after make_sockaddr_un(). */ +static void +free_sockaddr_un(int dirfd, const char *linkname) +{ + if (dirfd >= 0) { + close(dirfd); + } + if (linkname[0]) { + fatal_signal_unlink_file_now(linkname); } } @@ -357,12 +513,11 @@ bind_unix_socket(int fd, struct sockaddr *sun, socklen_t sun_len) /* 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. + * is true, the socket is made non-blocking. * * Returns the socket's fd if successful, otherwise a negative errno value. */ int -make_unix_socket(int style, bool nonblock, bool passcred OVS_UNUSED, +make_unix_socket(int style, bool nonblock, const char *bind_path, const char *connect_path) { int error; @@ -378,67 +533,53 @@ make_unix_socket(int style, bool nonblock, bool passcred OVS_UNUSED, * 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) { - error = errno; - goto error; - } - if (fcntl(fd, F_SETFL, flags | O_NONBLOCK) == -1) { - error = errno; + error = set_nonblocking(fd); + if (error) { goto error; } } if (bind_path) { + char linkname[MAX_UN_LEN + 1]; struct sockaddr_un un; socklen_t un_len; int dirfd; if (unlink(bind_path) && errno != ENOENT) { - VLOG_WARN("unlinking \"%s\": %s\n", bind_path, strerror(errno)); + VLOG_WARN("unlinking \"%s\": %s\n", + bind_path, ovs_strerror(errno)); } fatal_signal_add_file_to_unlink(bind_path); - error = make_sockaddr_un(bind_path, &un, &un_len, &dirfd); + error = make_sockaddr_un(bind_path, &un, &un_len, &dirfd, linkname); if (!error) { error = bind_unix_socket(fd, (struct sockaddr *) &un, un_len); } - if (dirfd >= 0) { - close(dirfd); - } + free_sockaddr_un(dirfd, linkname); + if (error) { goto error; } } if (connect_path) { + char linkname[MAX_UN_LEN + 1]; struct sockaddr_un un; socklen_t un_len; int dirfd; - error = make_sockaddr_un(connect_path, &un, &un_len, &dirfd); + error = make_sockaddr_un(connect_path, &un, &un_len, &dirfd, linkname); if (!error && connect(fd, (struct sockaddr*) &un, un_len) && errno != EINPROGRESS) { error = errno; } - if (dirfd >= 0) { - close(dirfd); - } - if (error) { - goto error; - } - } + free_sockaddr_un(dirfd, linkname); -#ifdef SCM_CREDENTIALS - if (passcred) { - int enable = 1; - if (setsockopt(fd, SOL_SOCKET, SO_PASSCRED, &enable, sizeof(enable))) { - error = errno; + if (error) { goto error; } } -#endif return fd; @@ -447,7 +588,7 @@ error: error = EPROTO; } if (bind_path) { - fatal_signal_remove_file_to_unlink(bind_path); + fatal_signal_unlink_file_now(bind_path); } close(fd); return -error; @@ -533,10 +674,14 @@ exit: * and stores -1 into '*fdp'. * * If 'sinp' is non-null, then on success the target address is stored into - * '*sinp'. */ + * '*sinp'. + * + * 'dscp' becomes the DSCP bits in the IP headers for the new connection. It + * should be in the range [0, 63] and will automatically be shifted to the + * appropriately place in the IP tos field. */ int inet_open_active(int style, const char *target, uint16_t default_port, - struct sockaddr_in *sinp, int *fdp) + struct sockaddr_in *sinp, int *fdp, uint8_t dscp) { struct sockaddr_in sin; int fd = -1; @@ -551,37 +696,40 @@ inet_open_active(int style, const char *target, uint16_t default_port, /* Create non-blocking socket. */ fd = socket(AF_INET, style, 0); if (fd < 0) { - VLOG_ERR("%s: socket: %s", target, strerror(errno)); + VLOG_ERR("%s: socket: %s", target, ovs_strerror(errno)); error = errno; goto exit; } error = set_nonblocking(fd); if (error) { - goto exit_close; + goto exit; + } + + /* The dscp bits must be configured before connect() to ensure that the TOS + * field is set during the connection establishment. If set after + * connect(), the handshake SYN frames will be sent with a TOS of 0. */ + error = set_dscp(fd, dscp); + if (error) { + VLOG_ERR("%s: socket: %s", target, ovs_strerror(error)); + goto exit; } /* Connect. */ error = connect(fd, (struct sockaddr *) &sin, sizeof sin) == 0 ? 0 : errno; if (error == EINPROGRESS) { error = EAGAIN; - } else if (error && error != EAGAIN) { - goto exit_close; } - /* Success: error is 0 or EAGAIN. */ - goto exit; - -exit_close: - close(fd); exit: if (!error || error == EAGAIN) { if (sinp) { *sinp = sin; } - *fdp = fd; - } else { - *fdp = -1; + } else if (fd >= 0) { + close(fd); + fd = -1; } + *fdp = fd; return error; } @@ -598,7 +746,7 @@ exit: * If successful, stores the address into '*sinp' and returns true; otherwise * zeros '*sinp' and returns false. */ bool -inet_parse_passive(const char *target_, uint16_t default_port, +inet_parse_passive(const char *target_, int default_port, struct sockaddr_in *sinp) { char *target = xstrdup(target_); @@ -652,25 +800,30 @@ exit: * negative errno value. * * If 'sinp' is non-null, then on success the bound address is stored into - * '*sinp'. */ + * '*sinp'. + * + * 'dscp' becomes the DSCP bits in the IP headers for the new connection. It + * should be in the range [0, 63] and will automatically be shifted to the + * appropriately place in the IP tos field. */ int inet_open_passive(int style, const char *target, int default_port, - struct sockaddr_in *sinp) + struct sockaddr_in *sinp, uint8_t dscp) { + bool kernel_chooses_port; struct sockaddr_in sin; int fd = 0, error; unsigned int yes = 1; if (!inet_parse_passive(target, default_port, &sin)) { - return EAFNOSUPPORT; + return -EAFNOSUPPORT; } /* Create non-blocking socket, set SO_REUSEADDR. */ fd = socket(AF_INET, style, 0); if (fd < 0) { error = errno; - VLOG_ERR("%s: socket: %s", target, strerror(error)); - return error; + VLOG_ERR("%s: socket: %s", target, ovs_strerror(error)); + return -error; } error = set_nonblocking(fd); if (error) { @@ -679,43 +832,61 @@ inet_open_passive(int style, const char *target, int default_port, if (style == SOCK_STREAM && setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &yes, sizeof yes) < 0) { error = errno; - VLOG_ERR("%s: setsockopt(SO_REUSEADDR): %s", target, strerror(error)); + VLOG_ERR("%s: setsockopt(SO_REUSEADDR): %s", + target, ovs_strerror(error)); goto error; } /* Bind. */ if (bind(fd, (struct sockaddr *) &sin, sizeof sin) < 0) { error = errno; - VLOG_ERR("%s: bind: %s", target, strerror(error)); + VLOG_ERR("%s: bind: %s", target, ovs_strerror(error)); + goto error; + } + + /* The dscp bits must be configured before connect() to ensure that the TOS + * field is set during the connection establishment. If set after + * connect(), the handshake SYN frames will be sent with a TOS of 0. */ + error = set_dscp(fd, dscp); + if (error) { + VLOG_ERR("%s: socket: %s", target, ovs_strerror(error)); goto error; } /* Listen. */ - if (listen(fd, 10) < 0) { + if (style == SOCK_STREAM && listen(fd, 10) < 0) { error = errno; - VLOG_ERR("%s: listen: %s", target, strerror(error)); + VLOG_ERR("%s: listen: %s", target, ovs_strerror(error)); goto error; } - if (sinp) { + kernel_chooses_port = sin.sin_port == htons(0); + if (sinp || kernel_chooses_port) { socklen_t sin_len = sizeof sin; - if (getsockname(fd, (struct sockaddr *) &sin, &sin_len) < 0){ + if (getsockname(fd, (struct sockaddr *) &sin, &sin_len) < 0) { error = errno; - VLOG_ERR("%s: getsockname: %s", target, strerror(error)); + VLOG_ERR("%s: getsockname: %s", target, ovs_strerror(error)); goto error; } if (sin.sin_family != AF_INET || sin_len != sizeof sin) { + error = EAFNOSUPPORT; VLOG_ERR("%s: getsockname: invalid socket name", target); goto error; } - *sinp = sin; + if (sinp) { + *sinp = sin; + } + if (kernel_chooses_port) { + VLOG_INFO("%s: listening on port %"PRIu16, + target, ntohs(sin.sin_port)); + } } return fd; error: close(fd); - return error; + return -error; } /* Returns a readable and writable fd for /dev/null, if successful, otherwise @@ -724,15 +895,19 @@ error: int get_null_fd(void) { - static int null_fd = -1; - if (null_fd < 0) { + static struct ovsthread_once once = OVSTHREAD_ONCE_INITIALIZER; + static int null_fd; + + if (ovsthread_once_start(&once)) { null_fd = open("/dev/null", O_RDWR); if (null_fd < 0) { int error = errno; - VLOG_ERR("could not open /dev/null: %s", strerror(error)); - return -error; + VLOG_ERR("could not open /dev/null: %s", ovs_strerror(error)); + null_fd = -error; } + ovsthread_once_done(&once); } + return null_fd; } @@ -797,13 +972,13 @@ fsync_parent_dir(const char *file_name) * really an error. */ } else { error = errno; - VLOG_ERR("%s: fsync failed (%s)", dir, strerror(error)); + VLOG_ERR("%s: fsync failed (%s)", dir, ovs_strerror(error)); } } close(fd); } else { error = errno; - VLOG_ERR("%s: open failed (%s)", dir, strerror(error)); + VLOG_ERR("%s: open failed (%s)", dir, ovs_strerror(error)); } free(dir); @@ -841,18 +1016,48 @@ void xpipe(int fds[2]) { if (pipe(fds)) { - VLOG_FATAL("failed to create pipe (%s)", strerror(errno)); + VLOG_FATAL("failed to create pipe (%s)", ovs_strerror(errno)); + } +} + +void +xpipe_nonblocking(int fds[2]) +{ + xpipe(fds); + xset_nonblocking(fds[0]); + xset_nonblocking(fds[1]); +} + +void +xsocketpair(int domain, int type, int protocol, int fds[2]) +{ + if (socketpair(domain, type, protocol, fds)) { + VLOG_FATAL("failed to create socketpair (%s)", ovs_strerror(errno)); } } static int -getsockopt_int(int fd, int level, int optname, int *valuep) +getsockopt_int(int fd, int level, int option, const char *optname, int *valuep) { - socklen_t len = sizeof *valuep; + static struct vlog_rate_limit rl = VLOG_RATE_LIMIT_INIT(5, 10); + socklen_t len; + int value; + int error; - return (getsockopt(fd, level, optname, valuep, &len) ? errno - : len == sizeof *valuep ? 0 - : EINVAL); + len = sizeof value; + if (getsockopt(fd, level, option, &value, &len)) { + error = errno; + VLOG_ERR_RL(&rl, "getsockopt(%s): %s", optname, ovs_strerror(error)); + } else if (len != sizeof value) { + error = EINVAL; + VLOG_ERR_RL(&rl, "getsockopt(%s): value is %u bytes (expected %"PRIuSIZE")", + optname, (unsigned int) len, sizeof value); + } else { + error = 0; + } + + *valuep = error ? 0 : value; + return error; } static void @@ -868,7 +1073,7 @@ describe_sockaddr(struct ds *string, int fd, memcpy(&sin, &ss, sizeof sin); ds_put_format(string, IP_FMT":%"PRIu16, - IP_ARGS(&sin.sin_addr.s_addr), ntohs(sin.sin_port)); + IP_ARGS(sin.sin_addr.s_addr), ntohs(sin.sin_port)); } else if (ss.ss_family == AF_UNIX) { struct sockaddr_un sun; const char *null; @@ -890,7 +1095,8 @@ describe_sockaddr(struct ds *string, int fd, #define SO_PROTOCOL 38 #endif - if (!getsockopt_int(fd, SOL_SOCKET, SO_PROTOCOL, &protocol)) { + if (!getsockopt_int(fd, SOL_SOCKET, SO_PROTOCOL, "SO_PROTOCOL", + &protocol)) { switch (protocol) { case NETLINK_ROUTE: ds_put_cstr(string, "NETLINK_ROUTE"); @@ -909,7 +1115,7 @@ describe_sockaddr(struct ds *string, int fd, } } #endif -#if AF_PACKET && __linux__ +#if AF_PACKET && LINUX_DATAPATH else if (ss.ss_family == AF_PACKET) { struct sockaddr_ll sll; @@ -939,7 +1145,7 @@ describe_sockaddr(struct ds *string, int fd, } -#ifdef __linux__ +#ifdef LINUX_DATAPATH static void put_fd_filename(struct ds *string, int fd) { @@ -969,7 +1175,7 @@ describe_fd(int fd) ds_init(&string); if (fstat(fd, &s)) { - ds_put_format(&string, "fstat failed (%s)", strerror(errno)); + ds_put_format(&string, "fstat failed (%s)", ovs_strerror(errno)); } else if (S_ISSOCK(s.st_mode)) { describe_sockaddr(&string, fd, getsockname); ds_put_cstr(&string, "<->"); @@ -983,9 +1189,294 @@ describe_fd(int fd) : S_ISFIFO(s.st_mode) ? "FIFO" : S_ISLNK(s.st_mode) ? "symbolic link" : "unknown")); -#ifdef __linux__ +#ifdef LINUX_DATAPATH put_fd_filename(&string, fd); #endif } return ds_steal_cstr(&string); } + +/* Returns the total of the 'iov_len' members of the 'n_iovs' in 'iovs'. + * The caller must ensure that the total does not exceed SIZE_MAX. */ +size_t +iovec_len(const struct iovec iovs[], size_t n_iovs) +{ + size_t len = 0; + size_t i; + + for (i = 0; i < n_iovs; i++) { + len += iovs[i].iov_len; + } + return len; +} + +/* Returns true if all of the 'n_iovs' iovecs in 'iovs' have length zero. */ +bool +iovec_is_empty(const struct iovec iovs[], size_t n_iovs) +{ + size_t i; + + for (i = 0; i < n_iovs; i++) { + if (iovs[i].iov_len) { + return false; + } + } + return true; +} + +/* Sends the 'n_iovs' iovecs of data in 'iovs' and the 'n_fds' file descriptors + * in 'fds' on Unix domain socket 'sock'. Returns the number of bytes + * successfully sent or -1 if an error occurred. On error, sets errno + * appropriately. */ +int +send_iovec_and_fds(int sock, + const struct iovec *iovs, size_t n_iovs, + const int fds[], size_t n_fds) +{ + ovs_assert(sock >= 0); + if (n_fds > 0) { + union { + struct cmsghdr cm; + char control[CMSG_SPACE(SOUTIL_MAX_FDS * sizeof *fds)]; + } cmsg; + struct msghdr msg; + + ovs_assert(!iovec_is_empty(iovs, n_iovs)); + ovs_assert(n_fds <= SOUTIL_MAX_FDS); + + memset(&cmsg, 0, sizeof cmsg); + cmsg.cm.cmsg_len = CMSG_LEN(n_fds * sizeof *fds); + cmsg.cm.cmsg_level = SOL_SOCKET; + cmsg.cm.cmsg_type = SCM_RIGHTS; + memcpy(CMSG_DATA(&cmsg.cm), fds, n_fds * sizeof *fds); + + msg.msg_name = NULL; + msg.msg_namelen = 0; + msg.msg_iov = CONST_CAST(struct iovec *, iovs); + msg.msg_iovlen = n_iovs; + msg.msg_control = &cmsg.cm; + msg.msg_controllen = CMSG_SPACE(n_fds * sizeof *fds); + msg.msg_flags = 0; + + return sendmsg(sock, &msg, 0); + } else { + return writev(sock, iovs, n_iovs); + } +} + +/* Sends the 'n_iovs' iovecs of data in 'iovs' and the 'n_fds' file descriptors + * in 'fds' on Unix domain socket 'sock'. If 'skip_bytes' is nonzero, then the + * first 'skip_bytes' of data in the iovecs are not sent, and none of the file + * descriptors are sent. The function continues to retry sending until an + * error (other than EINTR) occurs or all the data and fds are sent. + * + * Returns 0 if all the data and fds were successfully sent, otherwise a + * positive errno value. Regardless of success, stores the number of bytes + * sent (always at least 'skip_bytes') in '*bytes_sent'. (If at least one byte + * is sent, then all the fds have been sent.) + * + * 'skip_bytes' must be less than or equal to iovec_len(iovs, n_iovs). */ +int +send_iovec_and_fds_fully(int sock, + const struct iovec iovs[], size_t n_iovs, + const int fds[], size_t n_fds, + size_t skip_bytes, size_t *bytes_sent) +{ + *bytes_sent = 0; + while (n_iovs > 0) { + int retval; + + if (skip_bytes) { + retval = skip_bytes; + skip_bytes = 0; + } else if (!*bytes_sent) { + retval = send_iovec_and_fds(sock, iovs, n_iovs, fds, n_fds); + } else { + retval = writev(sock, iovs, n_iovs); + } + + if (retval > 0) { + *bytes_sent += retval; + while (retval > 0) { + const uint8_t *base = iovs->iov_base; + size_t len = iovs->iov_len; + + if (retval < len) { + size_t sent; + int error; + + error = write_fully(sock, base + retval, len - retval, + &sent); + *bytes_sent += sent; + retval += sent; + if (error) { + return error; + } + } + retval -= len; + iovs++; + n_iovs--; + } + } else if (retval == 0) { + if (iovec_is_empty(iovs, n_iovs)) { + break; + } + VLOG_WARN("send returned 0"); + return EPROTO; + } else if (errno != EINTR) { + return errno; + } + } + + return 0; +} + +/* Sends the 'n_iovs' iovecs of data in 'iovs' and the 'n_fds' file descriptors + * in 'fds' on Unix domain socket 'sock'. The function continues to retry + * sending until an error (other than EAGAIN or EINTR) occurs or all the data + * and fds are sent. Upon EAGAIN, the function blocks until the socket is + * ready for more data. + * + * Returns 0 if all the data and fds were successfully sent, otherwise a + * positive errno value. */ +int +send_iovec_and_fds_fully_block(int sock, + const struct iovec iovs[], size_t n_iovs, + const int fds[], size_t n_fds) +{ + size_t sent = 0; + + for (;;) { + int error; + + error = send_iovec_and_fds_fully(sock, iovs, n_iovs, + fds, n_fds, sent, &sent); + if (error != EAGAIN) { + return error; + } + poll_fd_wait(sock, POLLOUT); + poll_block(); + } +} + +/* Attempts to receive from Unix domain socket 'sock' up to 'size' bytes of + * data into 'data' and up to SOUTIL_MAX_FDS file descriptors into 'fds'. + * + * - Upon success, returns the number of bytes of data copied into 'data' + * and stores the number of received file descriptors into '*n_fdsp'. + * + * - On failure, returns a negative errno value and stores 0 in + * '*n_fdsp'. + * + * - On EOF, returns 0 and stores 0 in '*n_fdsp'. */ +int +recv_data_and_fds(int sock, + void *data, size_t size, + int fds[SOUTIL_MAX_FDS], size_t *n_fdsp) +{ + union { + struct cmsghdr cm; + char control[CMSG_SPACE(SOUTIL_MAX_FDS * sizeof *fds)]; + } cmsg; + struct msghdr msg; + int retval; + struct cmsghdr *p; + size_t i; + + *n_fdsp = 0; + + do { + struct iovec iov; + + iov.iov_base = data; + iov.iov_len = size; + + msg.msg_name = NULL; + msg.msg_namelen = 0; + msg.msg_iov = &iov; + msg.msg_iovlen = 1; + msg.msg_control = &cmsg.cm; + msg.msg_controllen = sizeof cmsg.control; + msg.msg_flags = 0; + + retval = recvmsg(sock, &msg, 0); + } while (retval < 0 && errno == EINTR); + if (retval <= 0) { + return retval < 0 ? -errno : 0; + } + + for (p = CMSG_FIRSTHDR(&msg); p; p = CMSG_NXTHDR(&msg, p)) { + if (p->cmsg_level != SOL_SOCKET || p->cmsg_type != SCM_RIGHTS) { + VLOG_ERR("unexpected control message %d:%d", + p->cmsg_level, p->cmsg_type); + goto error; + } else if (*n_fdsp) { + VLOG_ERR("multiple SCM_RIGHTS received"); + goto error; + } else { + size_t n_fds = (p->cmsg_len - CMSG_LEN(0)) / sizeof *fds; + const int *fds_data = ALIGNED_CAST(const int *, CMSG_DATA(p)); + + ovs_assert(n_fds > 0); + if (n_fds > SOUTIL_MAX_FDS) { + VLOG_ERR("%"PRIuSIZE" fds received but only %d supported", + n_fds, SOUTIL_MAX_FDS); + for (i = 0; i < n_fds; i++) { + close(fds_data[i]); + } + goto error; + } + + *n_fdsp = n_fds; + memcpy(fds, fds_data, n_fds * sizeof *fds); + } + } + + return retval; + +error: + for (i = 0; i < *n_fdsp; i++) { + close(fds[i]); + } + *n_fdsp = 0; + return EPROTO; +} + +/* Calls ioctl() on an AF_INET sock, passing the specified 'command' and + * 'arg'. Returns 0 if successful, otherwise a positive errno value. */ +int +af_inet_ioctl(unsigned long int command, const void *arg) +{ + static struct ovsthread_once once = OVSTHREAD_ONCE_INITIALIZER; + static int sock; + + if (ovsthread_once_start(&once)) { + sock = socket(AF_INET, SOCK_DGRAM, 0); + if (sock < 0) { + sock = -errno; + VLOG_ERR("failed to create inet socket: %s", ovs_strerror(errno)); + } + ovsthread_once_done(&once); + } + + return (sock < 0 ? -sock + : ioctl(sock, command, arg) == -1 ? errno + : 0); +} + +int +af_inet_ifreq_ioctl(const char *name, struct ifreq *ifr, unsigned long int cmd, + const char *cmd_name) +{ + int error; + + ovs_strzcpy(ifr->ifr_name, name, sizeof ifr->ifr_name); + error = af_inet_ioctl(cmd, ifr); + if (error) { + static struct vlog_rate_limit rl = VLOG_RATE_LIMIT_INIT(5, 20); + VLOG_DBG_RL(&rl, "%s: ioctl(%s) failed: %s", name, cmd_name, + ovs_strerror(error)); + } + return error; +} +