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/*
Copyright (c) 2007-2016 Contributors as noted in the AUTHORS file
This file is part of libzmq, the ZeroMQ core engine in C++.
libzmq is free software; you can redistribute it and/or modify it under
the terms of the GNU Lesser General Public License (LGPL) as published
by the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
As a special exception, the Contributors give you permission to link
this library with independent modules to produce an executable,
regardless of the license terms of these independent modules, and to
copy and distribute the resulting executable under terms of your choice,
provided that you also meet, for each linked independent module, the
terms and conditions of the license of that module. An independent
module is a module which is not derived from or based on this library.
If you modify this library, you must extend this exception to your
version of the library.
libzmq is distributed in the hope that it will be useful, but WITHOUT
ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
License for more details.
You should have received a copy of the GNU Lesser General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include "precompiled.hpp"
#include "ip.hpp"
#include "err.hpp"
#include "macros.hpp"
#include "config.hpp"
#if !defined ZMQ_HAVE_WINDOWS
#include <fcntl.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netdb.h>
#include <netinet/in.h>
#include <netinet/tcp.h>
#else
#include "tcp.hpp"
#endif
#if defined ZMQ_HAVE_OPENVMS || defined ZMQ_HAVE_VXWORKS
#include <ioctl.h>
#endif
#if defined ZMQ_HAVE_VXWORKS
#include <unistd.h>
#include <sockLib.h>
#include <ioLib.h>
#endif
#if defined ZMQ_HAVE_EVENTFD
#include <sys/eventfd.h>
#endif
#if defined ZMQ_HAVE_OPENPGM
#ifdef ZMQ_HAVE_WINDOWS
#define __PGM_WININT_H__
#endif
#include <pgm/pgm.h>
#endif
#ifdef __APPLE__
#include <TargetConditionals.h>
#endif
zmq::fd_t zmq::open_socket (int domain_, int type_, int protocol_)
{
int rc;
// Setting this option result in sane behaviour when exec() functions
// are used. Old sockets are closed and don't block TCP ports etc.
#if defined ZMQ_HAVE_SOCK_CLOEXEC
type_ |= SOCK_CLOEXEC;
#endif
#if defined ZMQ_HAVE_WINDOWS && defined WSA_FLAG_NO_HANDLE_INHERIT
// if supported, create socket with WSA_FLAG_NO_HANDLE_INHERIT, such that
// the race condition in making it non-inheritable later is avoided
const fd_t s = WSASocket (domain_, type_, protocol_, NULL, 0,
WSA_FLAG_NO_HANDLE_INHERIT);
#else
const fd_t s = socket (domain_, type_, protocol_);
#endif
if (s == retired_fd) {
#ifdef ZMQ_HAVE_WINDOWS
errno = wsa_error_to_errno (WSAGetLastError ());
#endif
return retired_fd;
}
make_socket_noninheritable (s);
// Socket is not yet connected so EINVAL is not a valid networking error
rc = zmq::set_nosigpipe (s);
errno_assert (rc == 0);
return s;
}
void zmq::unblock_socket (fd_t s_)
{
#if defined ZMQ_HAVE_WINDOWS
u_long nonblock = 1;
int rc = ioctlsocket (s_, FIONBIO, &nonblock);
wsa_assert (rc != SOCKET_ERROR);
#elif defined ZMQ_HAVE_OPENVMS || defined ZMQ_HAVE_VXWORKS
int nonblock = 1;
int rc = ioctl (s_, FIONBIO, &nonblock);
errno_assert (rc != -1);
#else
int flags = fcntl (s_, F_GETFL, 0);
if (flags == -1)
flags = 0;
int rc = fcntl (s_, F_SETFL, flags | O_NONBLOCK);
errno_assert (rc != -1);
#endif
}
void zmq::enable_ipv4_mapping (fd_t s_)
{
(void) s_;
#if defined IPV6_V6ONLY && !defined ZMQ_HAVE_OPENBSD
#ifdef ZMQ_HAVE_WINDOWS
DWORD flag = 0;
#else
int flag = 0;
#endif
int rc = setsockopt (s_, IPPROTO_IPV6, IPV6_V6ONLY,
reinterpret_cast<char *> (&flag), sizeof (flag));
#ifdef ZMQ_HAVE_WINDOWS
wsa_assert (rc != SOCKET_ERROR);
#else
errno_assert (rc == 0);
#endif
#endif
}
int zmq::get_peer_ip_address (fd_t sockfd_, std::string &ip_addr_)
{
int rc;
struct sockaddr_storage ss;
#if defined ZMQ_HAVE_HPUX || defined ZMQ_HAVE_WINDOWS \
|| defined ZMQ_HAVE_VXWORKS
int addrlen = static_cast<int> (sizeof ss);
#else
socklen_t addrlen = sizeof ss;
#endif
rc = getpeername (sockfd_, reinterpret_cast<struct sockaddr *> (&ss),
&addrlen);
#ifdef ZMQ_HAVE_WINDOWS
if (rc == SOCKET_ERROR) {
const int last_error = WSAGetLastError ();
wsa_assert (last_error != WSANOTINITIALISED && last_error != WSAEFAULT
&& last_error != WSAEINPROGRESS
&& last_error != WSAENOTSOCK);
return 0;
}
#else
if (rc == -1) {
#if !defined(TARGET_OS_IPHONE) || !TARGET_OS_IPHONE
errno_assert (errno != EBADF && errno != EFAULT && errno != ENOTSOCK);
#else
errno_assert (errno != EFAULT && errno != ENOTSOCK);
#endif
return 0;
}
#endif
char host[NI_MAXHOST];
rc = getnameinfo (reinterpret_cast<struct sockaddr *> (&ss), addrlen, host,
sizeof host, NULL, 0, NI_NUMERICHOST);
if (rc != 0)
return 0;
ip_addr_ = host;
union
{
struct sockaddr sa;
struct sockaddr_storage sa_stor;
} u;
u.sa_stor = ss;
return static_cast<int> (u.sa.sa_family);
}
void zmq::set_ip_type_of_service (fd_t s_, int iptos_)
{
int rc = setsockopt (s_, IPPROTO_IP, IP_TOS,
reinterpret_cast<char *> (&iptos_), sizeof (iptos_));
#ifdef ZMQ_HAVE_WINDOWS
wsa_assert (rc != SOCKET_ERROR);
#else
errno_assert (rc == 0);
#endif
// Windows and Hurd do not support IPV6_TCLASS
#if !defined(ZMQ_HAVE_WINDOWS) && defined(IPV6_TCLASS)
rc = setsockopt (s_, IPPROTO_IPV6, IPV6_TCLASS,
reinterpret_cast<char *> (&iptos_), sizeof (iptos_));
// If IPv6 is not enabled ENOPROTOOPT will be returned on Linux and
// EINVAL on OSX
if (rc == -1) {
errno_assert (errno == ENOPROTOOPT || errno == EINVAL);
}
#endif
}
int zmq::set_nosigpipe (fd_t s_)
{
#ifdef SO_NOSIGPIPE
// Make sure that SIGPIPE signal is not generated when writing to a
// connection that was already closed by the peer.
// As per POSIX spec, EINVAL will be returned if the socket was valid but
// the connection has been reset by the peer. Return an error so that the
// socket can be closed and the connection retried if necessary.
int set = 1;
int rc = setsockopt (s_, SOL_SOCKET, SO_NOSIGPIPE, &set, sizeof (int));
if (rc != 0 && errno == EINVAL)
return -1;
errno_assert (rc == 0);
#else
LIBZMQ_UNUSED (s_);
#endif
return 0;
}
void zmq::bind_to_device (fd_t s_, std::string &bound_device_)
{
#ifdef ZMQ_HAVE_SO_BINDTODEVICE
int rc = setsockopt (s_, SOL_SOCKET, SO_BINDTODEVICE,
bound_device_.c_str (), bound_device_.length ());
#ifdef ZMQ_HAVE_WINDOWS
wsa_assert (rc != SOCKET_ERROR);
#else
errno_assert (rc == 0);
#endif
#else
LIBZMQ_UNUSED (s_);
LIBZMQ_UNUSED (bound_device_);
#endif
}
bool zmq::initialize_network ()
{
#if defined ZMQ_HAVE_OPENPGM
// Init PGM transport. Ensure threading and timer are enabled. Find PGM
// protocol ID. Note that if you want to use gettimeofday and sleep for
// openPGM timing, set environment variables PGM_TIMER to "GTOD" and
// PGM_SLEEP to "USLEEP".
pgm_error_t *pgm_error = NULL;
const bool ok = pgm_init (&pgm_error);
if (ok != TRUE) {
// Invalid parameters don't set pgm_error_t
zmq_assert (pgm_error != NULL);
if (pgm_error->domain == PGM_ERROR_DOMAIN_TIME
&& (pgm_error->code == PGM_ERROR_FAILED)) {
// Failed to access RTC or HPET device.
pgm_error_free (pgm_error);
errno = EINVAL;
return false;
}
// PGM_ERROR_DOMAIN_ENGINE: WSAStartup errors or missing WSARecvMsg.
zmq_assert (false);
}
#endif
#ifdef ZMQ_HAVE_WINDOWS
// Intialise Windows sockets. Note that WSAStartup can be called multiple
// times given that WSACleanup will be called for each WSAStartup.
WORD version_requested = MAKEWORD (2, 2);
WSADATA wsa_data;
int rc = WSAStartup (version_requested, &wsa_data);
zmq_assert (rc == 0);
zmq_assert (LOBYTE (wsa_data.wVersion) == 2
&& HIBYTE (wsa_data.wVersion) == 2);
#endif
return true;
}
void zmq::shutdown_network ()
{
#ifdef ZMQ_HAVE_WINDOWS
// On Windows, uninitialise socket layer.
int rc = WSACleanup ();
wsa_assert (rc != SOCKET_ERROR);
#endif
#if defined ZMQ_HAVE_OPENPGM
// Shut down the OpenPGM library.
if (pgm_shutdown () != TRUE)
zmq_assert (false);
#endif
}
#if defined ZMQ_HAVE_WINDOWS
static void tune_socket (const SOCKET socket_)
{
BOOL tcp_nodelay = 1;
int rc =
setsockopt (socket_, IPPROTO_TCP, TCP_NODELAY,
reinterpret_cast<char *> (&tcp_nodelay), sizeof tcp_nodelay);
wsa_assert (rc != SOCKET_ERROR);
zmq::tcp_tune_loopback_fast_path (socket_);
}
#endif
int zmq::make_fdpair (fd_t *r_, fd_t *w_)
{
#if defined ZMQ_HAVE_EVENTFD
int flags = 0;
#if defined ZMQ_HAVE_EVENTFD_CLOEXEC
// Setting this option result in sane behaviour when exec() functions
// are used. Old sockets are closed and don't block TCP ports, avoid
// leaks, etc.
flags |= EFD_CLOEXEC;
#endif
fd_t fd = eventfd (0, flags);
if (fd == -1) {
errno_assert (errno == ENFILE || errno == EMFILE);
*w_ = *r_ = -1;
return -1;
} else {
*w_ = *r_ = fd;
return 0;
}
#elif defined ZMQ_HAVE_WINDOWS
#if !defined _WIN32_WCE && !defined ZMQ_HAVE_WINDOWS_UWP
// Windows CE does not manage security attributes
SECURITY_DESCRIPTOR sd;
SECURITY_ATTRIBUTES sa;
memset (&sd, 0, sizeof sd);
memset (&sa, 0, sizeof sa);
InitializeSecurityDescriptor (&sd, SECURITY_DESCRIPTOR_REVISION);
SetSecurityDescriptorDacl (&sd, TRUE, 0, FALSE);
sa.nLength = sizeof (SECURITY_ATTRIBUTES);
sa.lpSecurityDescriptor = &sd;
#endif
// This function has to be in a system-wide critical section so that
// two instances of the library don't accidentally create signaler
// crossing the process boundary.
// We'll use named event object to implement the critical section.
// Note that if the event object already exists, the CreateEvent requests
// EVENT_ALL_ACCESS access right. If this fails, we try to open
// the event object asking for SYNCHRONIZE access only.
HANDLE sync = NULL;
// Create critical section only if using fixed signaler port
// Use problematic Event implementation for compatibility if using old port 5905.
// Otherwise use Mutex implementation.
int event_signaler_port = 5905;
if (signaler_port == event_signaler_port) {
#if !defined _WIN32_WCE && !defined ZMQ_HAVE_WINDOWS_UWP
sync =
CreateEventW (&sa, FALSE, TRUE, L"Global\\zmq-signaler-port-sync");
#else
sync =
CreateEventW (NULL, FALSE, TRUE, L"Global\\zmq-signaler-port-sync");
#endif
if (sync == NULL && GetLastError () == ERROR_ACCESS_DENIED)
sync = OpenEventW (SYNCHRONIZE | EVENT_MODIFY_STATE, FALSE,
L"Global\\zmq-signaler-port-sync");
win_assert (sync != NULL);
} else if (signaler_port != 0) {
wchar_t mutex_name[MAX_PATH];
#ifdef __MINGW32__
_snwprintf (mutex_name, MAX_PATH, L"Global\\zmq-signaler-port-%d",
signaler_port);
#else
swprintf (mutex_name, MAX_PATH, L"Global\\zmq-signaler-port-%d",
signaler_port);
#endif
#if !defined _WIN32_WCE && !defined ZMQ_HAVE_WINDOWS_UWP
sync = CreateMutexW (&sa, FALSE, mutex_name);
#else
sync = CreateMutexW (NULL, FALSE, mutex_name);
#endif
if (sync == NULL && GetLastError () == ERROR_ACCESS_DENIED)
sync = OpenMutexW (SYNCHRONIZE, FALSE, mutex_name);
win_assert (sync != NULL);
}
// Windows has no 'socketpair' function. CreatePipe is no good as pipe
// handles cannot be polled on. Here we create the socketpair by hand.
*w_ = INVALID_SOCKET;
*r_ = INVALID_SOCKET;
// Create listening socket.
SOCKET listener;
listener = open_socket (AF_INET, SOCK_STREAM, 0);
wsa_assert (listener != INVALID_SOCKET);
// Set SO_REUSEADDR and TCP_NODELAY on listening socket.
BOOL so_reuseaddr = 1;
int rc = setsockopt (listener, SOL_SOCKET, SO_REUSEADDR,
reinterpret_cast<char *> (&so_reuseaddr),
sizeof so_reuseaddr);
wsa_assert (rc != SOCKET_ERROR);
tune_socket (listener);
// Init sockaddr to signaler port.
struct sockaddr_in addr;
memset (&addr, 0, sizeof addr);
addr.sin_family = AF_INET;
addr.sin_addr.s_addr = htonl (INADDR_LOOPBACK);
addr.sin_port = htons (signaler_port);
// Create the writer socket.
*w_ = open_socket (AF_INET, SOCK_STREAM, 0);
wsa_assert (*w_ != INVALID_SOCKET);
// Set TCP_NODELAY on writer socket.
tune_socket (*w_);
if (sync != NULL) {
// Enter the critical section.
DWORD dwrc = WaitForSingleObject (sync, INFINITE);
zmq_assert (dwrc == WAIT_OBJECT_0 || dwrc == WAIT_ABANDONED);
}
// Bind listening socket to signaler port.
rc = bind (listener, reinterpret_cast<const struct sockaddr *> (&addr),
sizeof addr);
if (rc != SOCKET_ERROR && signaler_port == 0) {
// Retrieve ephemeral port number
int addrlen = sizeof addr;
rc = getsockname (listener, reinterpret_cast<struct sockaddr *> (&addr),
&addrlen);
}
// Listen for incoming connections.
if (rc != SOCKET_ERROR)
rc = listen (listener, 1);
// Connect writer to the listener.
if (rc != SOCKET_ERROR)
rc = connect (*w_, reinterpret_cast<struct sockaddr *> (&addr),
sizeof addr);
// Accept connection from writer.
if (rc != SOCKET_ERROR)
*r_ = accept (listener, NULL, NULL);
// Send/receive large chunk to work around TCP slow start
// This code is a workaround for #1608
if (*r_ != INVALID_SOCKET) {
size_t dummy_size =
1024 * 1024; // 1M to overload default receive buffer
unsigned char *dummy =
static_cast<unsigned char *> (malloc (dummy_size));
wsa_assert (dummy);
int still_to_send = static_cast<int> (dummy_size);
int still_to_recv = static_cast<int> (dummy_size);
while (still_to_send || still_to_recv) {
int nbytes;
if (still_to_send > 0) {
nbytes = ::send (
*w_,
reinterpret_cast<char *> (dummy + dummy_size - still_to_send),
still_to_send, 0);
wsa_assert (nbytes != SOCKET_ERROR);
still_to_send -= nbytes;
}
nbytes = ::recv (
*r_,
reinterpret_cast<char *> (dummy + dummy_size - still_to_recv),
still_to_recv, 0);
wsa_assert (nbytes != SOCKET_ERROR);
still_to_recv -= nbytes;
}
free (dummy);
}
// Save errno if error occurred in bind/listen/connect/accept.
int saved_errno = 0;
if (*r_ == INVALID_SOCKET)
saved_errno = WSAGetLastError ();
// We don't need the listening socket anymore. Close it.
rc = closesocket (listener);
wsa_assert (rc != SOCKET_ERROR);
if (sync != NULL) {
// Exit the critical section.
BOOL brc;
if (signaler_port == event_signaler_port)
brc = SetEvent (sync);
else
brc = ReleaseMutex (sync);
win_assert (brc != 0);
// Release the kernel object
brc = CloseHandle (sync);
win_assert (brc != 0);
}
if (*r_ != INVALID_SOCKET) {
make_socket_noninheritable (*r_);
return 0;
}
// Cleanup writer if connection failed
if (*w_ != INVALID_SOCKET) {
rc = closesocket (*w_);
wsa_assert (rc != SOCKET_ERROR);
*w_ = INVALID_SOCKET;
}
// Set errno from saved value
errno = wsa_error_to_errno (saved_errno);
return -1;
#elif defined ZMQ_HAVE_OPENVMS
// Whilst OpenVMS supports socketpair - it maps to AF_INET only. Further,
// it does not set the socket options TCP_NODELAY and TCP_NODELACK which
// can lead to performance problems.
//
// The bug will be fixed in V5.6 ECO4 and beyond. In the meantime, we'll
// create the socket pair manually.
struct sockaddr_in lcladdr;
memset (&lcladdr, 0, sizeof lcladdr);
lcladdr.sin_family = AF_INET;
lcladdr.sin_addr.s_addr = htonl (INADDR_LOOPBACK);
lcladdr.sin_port = 0;
int listener = open_socket (AF_INET, SOCK_STREAM, 0);
errno_assert (listener != -1);
int on = 1;
int rc = setsockopt (listener, IPPROTO_TCP, TCP_NODELAY, &on, sizeof on);
errno_assert (rc != -1);
rc = setsockopt (listener, IPPROTO_TCP, TCP_NODELACK, &on, sizeof on);
errno_assert (rc != -1);
rc = bind (listener, (struct sockaddr *) &lcladdr, sizeof lcladdr);
errno_assert (rc != -1);
socklen_t lcladdr_len = sizeof lcladdr;
rc = getsockname (listener, (struct sockaddr *) &lcladdr, &lcladdr_len);
errno_assert (rc != -1);
rc = listen (listener, 1);
errno_assert (rc != -1);
*w_ = open_socket (AF_INET, SOCK_STREAM, 0);
errno_assert (*w_ != -1);
rc = setsockopt (*w_, IPPROTO_TCP, TCP_NODELAY, &on, sizeof on);
errno_assert (rc != -1);
rc = setsockopt (*w_, IPPROTO_TCP, TCP_NODELACK, &on, sizeof on);
errno_assert (rc != -1);
rc = connect (*w_, (struct sockaddr *) &lcladdr, sizeof lcladdr);
errno_assert (rc != -1);
*r_ = accept (listener, NULL, NULL);
errno_assert (*r_ != -1);
close (listener);
return 0;
#elif defined ZMQ_HAVE_VXWORKS
struct sockaddr_in lcladdr;
memset (&lcladdr, 0, sizeof lcladdr);
lcladdr.sin_family = AF_INET;
lcladdr.sin_addr.s_addr = htonl (INADDR_LOOPBACK);
lcladdr.sin_port = 0;
int listener = open_socket (AF_INET, SOCK_STREAM, 0);
errno_assert (listener != -1);
int on = 1;
int rc =
setsockopt (listener, IPPROTO_TCP, TCP_NODELAY, (char *) &on, sizeof on);
errno_assert (rc != -1);
rc = bind (listener, (struct sockaddr *) &lcladdr, sizeof lcladdr);
errno_assert (rc != -1);
socklen_t lcladdr_len = sizeof lcladdr;
rc = getsockname (listener, (struct sockaddr *) &lcladdr,
(int *) &lcladdr_len);
errno_assert (rc != -1);
rc = listen (listener, 1);
errno_assert (rc != -1);
*w_ = open_socket (AF_INET, SOCK_STREAM, 0);
errno_assert (*w_ != -1);
rc = setsockopt (*w_, IPPROTO_TCP, TCP_NODELAY, (char *) &on, sizeof on);
errno_assert (rc != -1);
rc = connect (*w_, (struct sockaddr *) &lcladdr, sizeof lcladdr);
errno_assert (rc != -1);
*r_ = accept (listener, NULL, NULL);
errno_assert (*r_ != -1);
close (listener);
return 0;
#else
// All other implementations support socketpair()
int sv[2];
int type = SOCK_STREAM;
// Setting this option result in sane behaviour when exec() functions
// are used. Old sockets are closed and don't block TCP ports, avoid
// leaks, etc.
#if defined ZMQ_HAVE_SOCK_CLOEXEC
type |= SOCK_CLOEXEC;
#endif
int rc = socketpair (AF_UNIX, type, 0, sv);
if (rc == -1) {
errno_assert (errno == ENFILE || errno == EMFILE);
*w_ = *r_ = -1;
return -1;
} else {
make_socket_noninheritable (sv[0]);
make_socket_noninheritable (sv[1]);
*w_ = sv[0];
*r_ = sv[1];
return 0;
}
#endif
}
void zmq::make_socket_noninheritable (fd_t sock_)
{
#if defined ZMQ_HAVE_WINDOWS && !defined _WIN32_WCE \
&& !defined ZMQ_HAVE_WINDOWS_UWP
// On Windows, preventing sockets to be inherited by child processes.
const BOOL brc = SetHandleInformation (reinterpret_cast<HANDLE> (sock_),
HANDLE_FLAG_INHERIT, 0);
win_assert (brc);
#elif (!defined ZMQ_HAVE_SOCK_CLOEXEC || !defined HAVE_ACCEPT4) \
&& defined FD_CLOEXEC
// If there 's no SOCK_CLOEXEC, let's try the second best option.
// Race condition can cause socket not to be closed (if fork happens
// between accept and this point).
const int rc = fcntl (sock_, F_SETFD, FD_CLOEXEC);
errno_assert (rc != -1);
#else
LIBZMQ_UNUSED (sock_);
#endif
}