src/base/socket.cc - public/gem5 - Git at Google

 /*
  * Copyright (c) 2020 The Regents of the University of California
  * All rights reserved
  *
  * Copyright (c) 2002-2005 The Regents of The University of Michigan
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met: redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer;
  * redistributions in binary form must reproduce the above copyright
  * notice, this list of conditions and the following disclaimer in the
  * documentation and/or other materials provided with the distribution;
  * neither the name of the copyright holders nor the names of its
  * contributors may be used to endorse or promote products derived from
  * this software without specific prior written permission.
  *
  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */

 #include "base/socket.hh"

 #include <netinet/in.h>
 #include <netinet/tcp.h>
 #include <sys/socket.h>
 #include <sys/types.h>
 #include <sys/un.h>
 #include <unistd.h>

 #include <cerrno>

 #include "base/logging.hh"
 #include "base/output.hh"
 #include "base/str.hh"
 #include "base/types.hh"
 #include "sim/byteswap.hh"

 namespace gem5
 {
 namespace
 {

 bool
 isSocketNameAbstract(const std::string &path)
 {
     if (path.empty()) {
         return false;
     }
     // No null byte should be present in the path
     return path.front() == '@';
 }

 std::string
 resolve(const std::string &path)
 {
     if (path.empty()) {
         return path;
     }
     if (isSocketNameAbstract(path)) {
         return '\0' + path.substr(1);
     }
     return simout.resolve(path);
 }

 }  // namespace

 bool ListenSocket::listeningDisabled = false;
 bool ListenSocket::anyListening = false;

 bool ListenSocket::bindToLoopback = false;

 UnixSocketAddr
 UnixSocketAddr::build(const std::string &path)
 {
     sockaddr_un addr = {.sun_family = AF_UNIX, .sun_path = {}};

     const bool is_abstract = isSocketNameAbstract(path);
     size_t max_len = sizeof(addr.sun_path);
     if (!is_abstract) {
         // File based socket names need to be null terminated
         max_len -= 1;
     }

     std::string resolved_path = resolve(path);
     std::string fmt_path = replace(resolved_path, '\0', '@');
     if (resolved_path.size() > max_len) {
         resolved_path = resolved_path.substr(0, max_len);
         const std::string untruncated_path = std::move(fmt_path);
         fmt_path = replace(resolved_path, '\0', '@');
         warn("SocketPath: unix socket path truncated from '%s' to '%s'",
              untruncated_path, fmt_path);
     }

     // We can't use strncpy here, since abstract sockets start with \0 which
     // will make strncpy think that the string is empty.
     memcpy(addr.sun_path, resolved_path.c_str(), resolved_path.size());
     // We can't use sizeof(sockaddr_un) for abstract sockets, since all
     // sizeof(sun_path) bytes are used in representing the path.
     const size_t path_size =
         is_abstract ? resolved_path.size() : sizeof(addr.sun_path);
     const size_t addr_size = offsetof(sockaddr_un, sun_path) + path_size;

     return UnixSocketAddr{.addr = std::move(addr),
                           .addrSize = addr_size,
                           .isAbstract = is_abstract,
                           .formattedPath = std::move(fmt_path)};
 }

 void
 ListenSocket::cleanup()
 {
     listeningDisabled = false;
     anyListening = false;
     bindToLoopback = false;
 }

 void
 ListenSocket::disableAll()
 {
     if (anyListening)
         panic("Too late to disable all listeners, already have a listener");
     listeningDisabled = true;
 }

 bool
 ListenSocket::allDisabled()
 {
     return listeningDisabled;
 }

 void
 ListenSocket::loopbackOnly()
 {
     if (anyListening)
         panic("Too late to bind to loopback, already have a listener");
     bindToLoopback = true;
 }

 // Wrappers to stub out SOCK_CLOEXEC/accept4 availability

 int
 ListenSocket::socketCloexec(int domain, int type, int protocol)
 {
 #ifdef SOCK_CLOEXEC
     type |= SOCK_CLOEXEC;
 #endif
     return ::socket(domain, type, protocol);
 }

 int
 ListenSocket::acceptCloexec(int sockfd, struct sockaddr *addr,
                              socklen_t *addrlen)
 {
 #if defined(_GNU_SOURCE) && defined(SOCK_CLOEXEC)
     return ::accept4(sockfd, addr, addrlen, SOCK_CLOEXEC);
 #else
     return ::accept(sockfd, addr, addrlen);
 #endif
 }

 ////////////////////////////////////////////////////////////////////////
 //
 //

 ListenSocket::ListenSocket()
     : listening(false), fd(-1)
 {}

 ListenSocket::~ListenSocket()
 {
     if (fd != -1)
         close(fd);
 }

 // Create a socket and configure it for listening
 bool
 ListenSocket::listen(int port, bool reuse)
 {
     if (listening)
         panic("Socket already listening!");

     // only create socket if not already created by a previous call
     if (fd == -1) {
         fd = socketCloexec(PF_INET, SOCK_STREAM, 0);
         if (fd < 0)
             panic("Can't create socket:%s !", strerror(errno));
     }

     if (reuse) {
         int i = 1;
         if (::setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, (char *)&i,
                          sizeof(i)) < 0)
             panic("ListenSocket(listen): setsockopt() SO_REUSEADDR failed!");
     }

     struct sockaddr_in sockaddr;
     sockaddr.sin_family = PF_INET;
     sockaddr.sin_addr.s_addr =
         htobe<in_addr_t>(bindToLoopback ? INADDR_LOOPBACK : INADDR_ANY);
     sockaddr.sin_port = htons(port);
     // finally clear sin_zero
     std::memset(&sockaddr.sin_zero, 0, sizeof(sockaddr.sin_zero));
     int ret = ::bind(fd, (struct sockaddr *)&sockaddr, sizeof (sockaddr));
     if (ret != 0) {
         if (ret == -1 && errno != EADDRINUSE)
             panic("ListenSocket(listen): bind() failed!");
         return false;
     }

     if (::listen(fd, 1) == -1) {
         if (errno != EADDRINUSE)
             panic("ListenSocket(listen): listen() failed!");
         // User may decide to retry with a different port later; however, the
         // socket is already bound to a port and the next bind will surely
         // fail. We'll close the socket and reset fd to -1 so our user can
         // retry with a cleaner state.
         close(fd);
         fd = -1;
         return false;
     }

     listening = true;
     anyListening = true;
     return true;
 }


 // Open a connection.  Accept will block, so if you don't want it to,
 // make sure a connection is ready before you call accept.
 int
 ListenSocket::accept(bool nodelay)
 {
     struct sockaddr_in sockaddr;
     socklen_t slen = sizeof (sockaddr);
     int sfd = acceptCloexec(fd, (struct sockaddr *)&sockaddr, &slen);
     if (sfd != -1 && nodelay) {
         int i = 1;
         if (::setsockopt(sfd, IPPROTO_TCP, TCP_NODELAY, (char *)&i,
                          sizeof(i)) < 0)
             warn("ListenSocket(accept): setsockopt() TCP_NODELAY failed!");
     }

     return sfd;
 }

 } // namespace gem5
	/*
	* Copyright (c) 2020 The Regents of the University of California
	* All rights reserved
	*
	* Copyright (c) 2002-2005 The Regents of The University of Michigan
	* All rights reserved.
	*
	* Redistribution and use in source and binary forms, with or without
	* modification, are permitted provided that the following conditions are
	* met: redistributions of source code must retain the above copyright
	* notice, this list of conditions and the following disclaimer;
	* redistributions in binary form must reproduce the above copyright
	* notice, this list of conditions and the following disclaimer in the
	* documentation and/or other materials provided with the distribution;
	* neither the name of the copyright holders nor the names of its
	* contributors may be used to endorse or promote products derived from
	* this software without specific prior written permission.
	*
	* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
	* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
	* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
	* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
	* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
	* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
	* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
	* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
	* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
	* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
	* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
	*/

	#include "base/socket.hh"

	#include <netinet/in.h>
	#include <netinet/tcp.h>
	#include <sys/socket.h>
	#include <sys/types.h>
	#include <sys/un.h>
	#include <unistd.h>

	#include <cerrno>

	#include "base/logging.hh"
	#include "base/output.hh"
	#include "base/str.hh"
	#include "base/types.hh"
	#include "sim/byteswap.hh"

	namespace gem5
	{
	namespace
	{

	bool
	isSocketNameAbstract(const std::string &path)
	{
	if (path.empty()) {
	return false;
	}
	// No null byte should be present in the path
	return path.front() == '@';
	}

	std::string
	resolve(const std::string &path)
	{
	if (path.empty()) {
	return path;
	}
	if (isSocketNameAbstract(path)) {
	return '\0' + path.substr(1);
	}
	return simout.resolve(path);
	}

	} // namespace

	bool ListenSocket::listeningDisabled = false;
	bool ListenSocket::anyListening = false;

	bool ListenSocket::bindToLoopback = false;

	UnixSocketAddr
	UnixSocketAddr::build(const std::string &path)
	{
	sockaddr_un addr = {.sun_family = AF_UNIX, .sun_path = {}};

	const bool is_abstract = isSocketNameAbstract(path);
	size_t max_len = sizeof(addr.sun_path);
	if (!is_abstract) {
	// File based socket names need to be null terminated
	max_len -= 1;
	}

	std::string resolved_path = resolve(path);
	std::string fmt_path = replace(resolved_path, '\0', '@');
	if (resolved_path.size() > max_len) {
	resolved_path = resolved_path.substr(0, max_len);
	const std::string untruncated_path = std::move(fmt_path);
	fmt_path = replace(resolved_path, '\0', '@');
	warn("SocketPath: unix socket path truncated from '%s' to '%s'",
	untruncated_path, fmt_path);
	}

	// We can't use strncpy here, since abstract sockets start with \0 which
	// will make strncpy think that the string is empty.
	memcpy(addr.sun_path, resolved_path.c_str(), resolved_path.size());
	// We can't use sizeof(sockaddr_un) for abstract sockets, since all
	// sizeof(sun_path) bytes are used in representing the path.
	const size_t path_size =
	is_abstract ? resolved_path.size() : sizeof(addr.sun_path);
	const size_t addr_size = offsetof(sockaddr_un, sun_path) + path_size;

	return UnixSocketAddr{.addr = std::move(addr),
	.addrSize = addr_size,
	.isAbstract = is_abstract,
	.formattedPath = std::move(fmt_path)};
	}

	void
	ListenSocket::cleanup()
	{
	listeningDisabled = false;
	anyListening = false;
	bindToLoopback = false;
	}

	void
	ListenSocket::disableAll()
	{
	if (anyListening)
	panic("Too late to disable all listeners, already have a listener");
	listeningDisabled = true;
	}

	bool
	ListenSocket::allDisabled()
	{
	return listeningDisabled;
	}

	void
	ListenSocket::loopbackOnly()
	{
	if (anyListening)
	panic("Too late to bind to loopback, already have a listener");
	bindToLoopback = true;
	}

	// Wrappers to stub out SOCK_CLOEXEC/accept4 availability

	int
	ListenSocket::socketCloexec(int domain, int type, int protocol)
	{
	#ifdef SOCK_CLOEXEC
	type \|= SOCK_CLOEXEC;
	#endif
	return ::socket(domain, type, protocol);
	}

	int
	ListenSocket::acceptCloexec(int sockfd, struct sockaddr *addr,
	socklen_t *addrlen)
	{
	#if defined(_GNU_SOURCE) && defined(SOCK_CLOEXEC)
	return ::accept4(sockfd, addr, addrlen, SOCK_CLOEXEC);
	#else
	return ::accept(sockfd, addr, addrlen);
	#endif
	}

	////////////////////////////////////////////////////////////////////////
	//
	//

	ListenSocket::ListenSocket()
	: listening(false), fd(-1)
	{}

	ListenSocket::~ListenSocket()
	{
	if (fd != -1)
	close(fd);
	}

	// Create a socket and configure it for listening
	bool
	ListenSocket::listen(int port, bool reuse)
	{
	if (listening)
	panic("Socket already listening!");

	// only create socket if not already created by a previous call
	if (fd == -1) {
	fd = socketCloexec(PF_INET, SOCK_STREAM, 0);
	if (fd < 0)
	panic("Can't create socket:%s !", strerror(errno));
	}

	if (reuse) {
	int i = 1;
	if (::setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, (char *)&i,
	sizeof(i)) < 0)
	panic("ListenSocket(listen): setsockopt() SO_REUSEADDR failed!");
	}

	struct sockaddr_in sockaddr;
	sockaddr.sin_family = PF_INET;
	sockaddr.sin_addr.s_addr =
	htobe<in_addr_t>(bindToLoopback ? INADDR_LOOPBACK : INADDR_ANY);
	sockaddr.sin_port = htons(port);
	// finally clear sin_zero
	std::memset(&sockaddr.sin_zero, 0, sizeof(sockaddr.sin_zero));
	int ret = ::bind(fd, (struct sockaddr *)&sockaddr, sizeof (sockaddr));
	if (ret != 0) {
	if (ret == -1 && errno != EADDRINUSE)
	panic("ListenSocket(listen): bind() failed!");
	return false;
	}

	if (::listen(fd, 1) == -1) {
	if (errno != EADDRINUSE)
	panic("ListenSocket(listen): listen() failed!");
	// User may decide to retry with a different port later; however, the
	// socket is already bound to a port and the next bind will surely
	// fail. We'll close the socket and reset fd to -1 so our user can
	// retry with a cleaner state.
	close(fd);
	fd = -1;
	return false;
	}

	listening = true;
	anyListening = true;
	return true;
	}


	// Open a connection. Accept will block, so if you don't want it to,
	// make sure a connection is ready before you call accept.
	int
	ListenSocket::accept(bool nodelay)
	{
	struct sockaddr_in sockaddr;
	socklen_t slen = sizeof (sockaddr);
	int sfd = acceptCloexec(fd, (struct sockaddr *)&sockaddr, &slen);
	if (sfd != -1 && nodelay) {
	int i = 1;
	if (::setsockopt(sfd, IPPROTO_TCP, TCP_NODELAY, (char *)&i,
	sizeof(i)) < 0)
	warn("ListenSocket(accept): setsockopt() TCP_NODELAY failed!");
	}

	return sfd;
	}

	} // namespace gem5