minetest/src/socket.cpp

592 lines
14 KiB
C++

/*
Minetest
Copyright (C) 2013 celeron55, Perttu Ahola <celeron55@gmail.com>
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU Lesser General Public License as published by
the Free Software Foundation; either version 2.1 of the License, or
(at your option) any later version.
This program 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, write to the Free Software Foundation, Inc.,
51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
#include "socket.h"
#include <stdio.h>
#include <iostream>
#include <stdlib.h>
#include <string.h>
#include <errno.h>
#include <sstream>
#include <iomanip>
#include "util/string.h"
#include "util/numeric.h"
#include "constants.h"
#include "debug.h"
#include "settings.h"
#include "log.h"
#ifdef _WIN32
#ifndef WIN32_LEAN_AND_MEAN
#define WIN32_LEAN_AND_MEAN
#endif
// Without this some of the network functions are not found on mingw
#ifndef _WIN32_WINNT
#define _WIN32_WINNT 0x0501
#endif
#include <windows.h>
#include <winsock2.h>
#include <ws2tcpip.h>
#define LAST_SOCKET_ERR() WSAGetLastError()
typedef SOCKET socket_t;
typedef int socklen_t;
#else
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <fcntl.h>
#include <netdb.h>
#include <unistd.h>
#include <arpa/inet.h>
#define LAST_SOCKET_ERR() (errno)
typedef int socket_t;
#endif
// Set to true to enable verbose debug output
bool socket_enable_debug_output = false; // yuck
static bool g_sockets_initialized = false;
// Initialize sockets
void sockets_init()
{
#ifdef _WIN32
// Windows needs sockets to be initialized before use
WSADATA WsaData;
if(WSAStartup( MAKEWORD(2,2), &WsaData ) != NO_ERROR)
throw SocketException("WSAStartup failed");
#endif
g_sockets_initialized = true;
}
void sockets_cleanup()
{
#ifdef _WIN32
// On Windows, cleanup sockets after use
WSACleanup();
#endif
}
/*
Address
*/
Address::Address()
{
m_addr_family = 0;
memset(&m_address, 0, sizeof(m_address));
m_port = 0;
}
Address::Address(u32 address, u16 port)
{
memset(&m_address, 0, sizeof(m_address));
setAddress(address);
setPort(port);
}
Address::Address(u8 a, u8 b, u8 c, u8 d, u16 port)
{
memset(&m_address, 0, sizeof(m_address));
setAddress(a, b, c, d);
setPort(port);
}
Address::Address(const IPv6AddressBytes *ipv6_bytes, u16 port)
{
memset(&m_address, 0, sizeof(m_address));
setAddress(ipv6_bytes);
setPort(port);
}
// Equality (address family, address and port must be equal)
bool Address::operator==(const Address &address)
{
if(address.m_addr_family != m_addr_family || address.m_port != m_port)
return false;
else if(m_addr_family == AF_INET)
{
return m_address.ipv4.sin_addr.s_addr ==
address.m_address.ipv4.sin_addr.s_addr;
}
else if(m_addr_family == AF_INET6)
{
return memcmp(m_address.ipv6.sin6_addr.s6_addr,
address.m_address.ipv6.sin6_addr.s6_addr, 16) == 0;
}
else
return false;
}
bool Address::operator!=(const Address &address)
{
return !(*this == address);
}
void Address::Resolve(const char *name)
{
if (!name || name[0] == 0) {
if (m_addr_family == AF_INET) {
setAddress((u32) 0);
} else if (m_addr_family == AF_INET6) {
setAddress((IPv6AddressBytes*) 0);
}
return;
}
struct addrinfo *resolved, hints;
memset(&hints, 0, sizeof(hints));
// Setup hints
hints.ai_socktype = 0;
hints.ai_protocol = 0;
hints.ai_flags = 0;
if(g_settings->getBool("enable_ipv6"))
{
// AF_UNSPEC allows both IPv6 and IPv4 addresses to be returned
hints.ai_family = AF_UNSPEC;
}
else
{
hints.ai_family = AF_INET;
}
// Do getaddrinfo()
int e = getaddrinfo(name, NULL, &hints, &resolved);
if(e != 0)
throw ResolveError(gai_strerror(e));
// Copy data
if(resolved->ai_family == AF_INET)
{
struct sockaddr_in *t = (struct sockaddr_in *) resolved->ai_addr;
m_addr_family = AF_INET;
m_address.ipv4 = *t;
}
else if(resolved->ai_family == AF_INET6)
{
struct sockaddr_in6 *t = (struct sockaddr_in6 *) resolved->ai_addr;
m_addr_family = AF_INET6;
m_address.ipv6 = *t;
}
else
{
freeaddrinfo(resolved);
throw ResolveError("");
}
freeaddrinfo(resolved);
}
// IP address -> textual representation
std::string Address::serializeString() const
{
// windows XP doesnt have inet_ntop, maybe use better func
#ifdef _WIN32
if(m_addr_family == AF_INET)
{
u8 a, b, c, d;
u32 addr;
addr = ntohl(m_address.ipv4.sin_addr.s_addr);
a = (addr & 0xFF000000) >> 24;
b = (addr & 0x00FF0000) >> 16;
c = (addr & 0x0000FF00) >> 8;
d = (addr & 0x000000FF);
return itos(a) + "." + itos(b) + "." + itos(c) + "." + itos(d);
}
else if(m_addr_family == AF_INET6)
{
std::ostringstream os;
for(int i = 0; i < 16; i += 2)
{
u16 section =
(m_address.ipv6.sin6_addr.s6_addr[i] << 8) |
(m_address.ipv6.sin6_addr.s6_addr[i + 1]);
os << std::hex << section;
if(i < 14)
os << ":";
}
return os.str();
}
else
return std::string("");
#else
char str[INET6_ADDRSTRLEN];
if (inet_ntop(m_addr_family, (m_addr_family == AF_INET) ? (void*)&(m_address.ipv4.sin_addr) : (void*)&(m_address.ipv6.sin6_addr), str, INET6_ADDRSTRLEN) == NULL) {
return std::string("");
}
return std::string(str);
#endif
}
struct sockaddr_in Address::getAddress() const
{
return m_address.ipv4; // NOTE: NO PORT INCLUDED, use getPort()
}
struct sockaddr_in6 Address::getAddress6() const
{
return m_address.ipv6; // NOTE: NO PORT INCLUDED, use getPort()
}
u16 Address::getPort() const
{
return m_port;
}
int Address::getFamily() const
{
return m_addr_family;
}
bool Address::isIPv6() const
{
return m_addr_family == AF_INET6;
}
bool Address::isZero() const
{
if (m_addr_family == AF_INET) {
return m_address.ipv4.sin_addr.s_addr == 0;
} else if (m_addr_family == AF_INET6) {
static const char zero[16] = {0};
return memcmp(m_address.ipv6.sin6_addr.s6_addr,
zero, 16) == 0;
}
return false;
}
void Address::setAddress(u32 address)
{
m_addr_family = AF_INET;
m_address.ipv4.sin_family = AF_INET;
m_address.ipv4.sin_addr.s_addr = htonl(address);
}
void Address::setAddress(u8 a, u8 b, u8 c, u8 d)
{
m_addr_family = AF_INET;
m_address.ipv4.sin_family = AF_INET;
u32 addr = htonl((a << 24) | (b << 16) | (c << 8) | d);
m_address.ipv4.sin_addr.s_addr = addr;
}
void Address::setAddress(const IPv6AddressBytes *ipv6_bytes)
{
m_addr_family = AF_INET6;
m_address.ipv6.sin6_family = AF_INET6;
if (ipv6_bytes)
memcpy(m_address.ipv6.sin6_addr.s6_addr, ipv6_bytes->bytes, 16);
else
memset(m_address.ipv6.sin6_addr.s6_addr, 0, 16);
}
void Address::setPort(u16 port)
{
m_port = port;
}
void Address::print(std::ostream *s) const
{
if(m_addr_family == AF_INET6)
*s << "[" << serializeString() << "]:" << m_port;
else
*s << serializeString() << ":" << m_port;
}
/*
UDPSocket
*/
UDPSocket::UDPSocket(bool ipv6)
{
init(ipv6, false);
}
bool UDPSocket::init(bool ipv6, bool noExceptions)
{
if (g_sockets_initialized == false) {
dstream << "Sockets not initialized" << std::endl;
return false;
}
// Use IPv6 if specified
m_addr_family = ipv6 ? AF_INET6 : AF_INET;
m_handle = socket(m_addr_family, SOCK_DGRAM, IPPROTO_UDP);
if (socket_enable_debug_output) {
dstream << "UDPSocket(" << (int) m_handle
<< ")::UDPSocket(): ipv6 = "
<< (ipv6 ? "true" : "false")
<< std::endl;
}
if (m_handle <= 0) {
if (noExceptions) {
return false;
} else {
throw SocketException(std::string("Failed to create socket: error ")
+ itos(LAST_SOCKET_ERR()));
}
}
setTimeoutMs(0);
return true;
}
UDPSocket::~UDPSocket()
{
if (socket_enable_debug_output) {
dstream << "UDPSocket( " << (int) m_handle << ")::~UDPSocket()"
<< std::endl;
}
#ifdef _WIN32
closesocket(m_handle);
#else
close(m_handle);
#endif
}
void UDPSocket::Bind(Address addr)
{
if(socket_enable_debug_output) {
dstream << "UDPSocket(" << (int) m_handle << ")::Bind(): "
<< addr.serializeString() << ":"
<< addr.getPort() << std::endl;
}
if (addr.getFamily() != m_addr_family) {
static const char *errmsg = "Socket and bind address families do not match";
errorstream << "Bind failed: " << errmsg << std::endl;
throw SocketException(errmsg);
}
if(m_addr_family == AF_INET6) {
struct sockaddr_in6 address;
memset(&address, 0, sizeof(address));
address = addr.getAddress6();
address.sin6_family = AF_INET6;
address.sin6_port = htons(addr.getPort());
if(bind(m_handle, (const struct sockaddr *) &address,
sizeof(struct sockaddr_in6)) < 0) {
dstream << (int) m_handle << ": Bind failed: "
<< strerror(errno) << std::endl;
throw SocketException("Failed to bind socket");
}
} else {
struct sockaddr_in address;
memset(&address, 0, sizeof(address));
address = addr.getAddress();
address.sin_family = AF_INET;
address.sin_port = htons(addr.getPort());
if (bind(m_handle, (const struct sockaddr *) &address,
sizeof(struct sockaddr_in)) < 0) {
dstream << (int)m_handle << ": Bind failed: "
<< strerror(errno) << std::endl;
throw SocketException("Failed to bind socket");
}
}
}
void UDPSocket::Send(const Address & destination, const void * data, int size)
{
bool dumping_packet = false; // for INTERNET_SIMULATOR
if(INTERNET_SIMULATOR)
dumping_packet = myrand() % INTERNET_SIMULATOR_PACKET_LOSS == 0;
if(socket_enable_debug_output) {
// Print packet destination and size
dstream << (int)m_handle << " -> ";
destination.print(&dstream);
dstream << ", size=" << size;
// Print packet contents
dstream << ", data=";
for(int i = 0; i < size && i < 20; i++) {
if(i % 2 == 0)
dstream << " ";
unsigned int a = ((const unsigned char *)data)[i];
dstream << std::hex << std::setw(2) << std::setfill('0') << a;
}
if(size > 20)
dstream << "...";
if(dumping_packet)
dstream << " (DUMPED BY INTERNET_SIMULATOR)";
dstream << std::endl;
}
if(dumping_packet) {
// Lol let's forget it
dstream << "UDPSocket::Send(): INTERNET_SIMULATOR: dumping packet."
<< std::endl;
return;
}
if(destination.getFamily() != m_addr_family)
throw SendFailedException("Address family mismatch");
int sent;
if(m_addr_family == AF_INET6) {
struct sockaddr_in6 address = destination.getAddress6();
address.sin6_port = htons(destination.getPort());
sent = sendto(m_handle, (const char *)data, size,
0, (struct sockaddr *)&address, sizeof(struct sockaddr_in6));
} else {
struct sockaddr_in address = destination.getAddress();
address.sin_port = htons(destination.getPort());
sent = sendto(m_handle, (const char *)data, size,
0, (struct sockaddr *)&address, sizeof(struct sockaddr_in));
}
if(sent != size)
throw SendFailedException("Failed to send packet");
}
int UDPSocket::Receive(Address & sender, void *data, int size)
{
// Return on timeout
if(WaitData(m_timeout_ms) == false)
return -1;
int received;
if (m_addr_family == AF_INET6) {
struct sockaddr_in6 address;
memset(&address, 0, sizeof(address));
socklen_t address_len = sizeof(address);
received = recvfrom(m_handle, (char *) data,
size, 0, (struct sockaddr *) &address, &address_len);
if(received < 0)
return -1;
u16 address_port = ntohs(address.sin6_port);
IPv6AddressBytes bytes;
memcpy(bytes.bytes, address.sin6_addr.s6_addr, 16);
sender = Address(&bytes, address_port);
} else {
struct sockaddr_in address;
memset(&address, 0, sizeof(address));
socklen_t address_len = sizeof(address);
received = recvfrom(m_handle, (char *)data,
size, 0, (struct sockaddr *)&address, &address_len);
if(received < 0)
return -1;
u32 address_ip = ntohl(address.sin_addr.s_addr);
u16 address_port = ntohs(address.sin_port);
sender = Address(address_ip, address_port);
}
if (socket_enable_debug_output) {
// Print packet sender and size
dstream << (int) m_handle << " <- ";
sender.print(&dstream);
dstream << ", size=" << received;
// Print packet contents
dstream << ", data=";
for(int i = 0; i < received && i < 20; i++) {
if(i % 2 == 0)
dstream << " ";
unsigned int a = ((const unsigned char *) data)[i];
dstream << std::hex << std::setw(2) << std::setfill('0') << a;
}
if(received > 20)
dstream << "...";
dstream << std::endl;
}
return received;
}
int UDPSocket::GetHandle()
{
return m_handle;
}
void UDPSocket::setTimeoutMs(int timeout_ms)
{
m_timeout_ms = timeout_ms;
}
bool UDPSocket::WaitData(int timeout_ms)
{
fd_set readset;
int result;
// Initialize the set
FD_ZERO(&readset);
FD_SET(m_handle, &readset);
// Initialize time out struct
struct timeval tv;
tv.tv_sec = 0;
tv.tv_usec = timeout_ms * 1000;
// select()
result = select(m_handle+1, &readset, NULL, NULL, &tv);
if (result == 0)
return false;
else if (result < 0 && (errno == EINTR || errno == EBADF)) {
// N.B. select() fails when sockets are destroyed on Connection's dtor
// with EBADF. Instead of doing tricky synchronization, allow this
// thread to exit but don't throw an exception.
return false;
} else if (result < 0) {
dstream << (int) m_handle << ": Select failed: "
<< strerror(errno) << std::endl;
#ifdef _WIN32
int e = WSAGetLastError();
dstream << (int) m_handle << ": WSAGetLastError()="
<< e << std::endl;
if (e == 10004 /* WSAEINTR */ || e == 10009 /* WSAEBADF */) {
infostream << "Ignoring WSAEINTR/WSAEBADF." << std::endl;
return false;
}
#endif
throw SocketException("Select failed");
} else if(FD_ISSET(m_handle, &readset) == false) {
// No data
return false;
}
// There is data
return true;
}