ladybird/Userland/Libraries/LibCore/Socket.cpp
Andrew Kaster f7c7954314 LibCore: Tolerate misaligned addresses in struct hostent
macOS's C library is not a good neighbor and doesn't ensure that
the entry in struct hostent's h_addr_list are aligned properly for
a char const*. In Socket::connect, use ByteReader instead of a c-style
cast to work around this possible misalignment.
2021-07-12 18:42:45 +04:30

209 lines
5.8 KiB
C++

/*
* Copyright (c) 2018-2020, Andreas Kling <kling@serenityos.org>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#include <AK/ByteBuffer.h>
#include <AK/ByteReader.h>
#include <AK/Debug.h>
#include <LibCore/Notifier.h>
#include <LibCore/Socket.h>
#include <arpa/inet.h>
#include <errno.h>
#include <fcntl.h>
#include <netdb.h>
#include <netinet/in.h>
#include <stdio.h>
#include <stdlib.h>
#include <sys/socket.h>
#include <unistd.h>
namespace Core {
Socket::Socket(Type type, Object* parent)
: IODevice(parent)
, m_type(type)
{
register_property(
"source_address", [this] { return m_source_address.to_string(); },
[](auto&) { return false; });
register_property(
"destination_address", [this] { return m_destination_address.to_string(); },
[](auto&) { return false; });
register_property(
"source_port", [this] { return m_source_port; },
[](auto&) { return false; });
register_property(
"destination_port", [this] { return m_destination_port; },
[](auto&) { return false; });
register_property(
"connected", [this] { return m_connected; },
[](auto&) { return false; });
}
Socket::~Socket()
{
close();
}
bool Socket::connect(const String& hostname, int port)
{
auto* hostent = gethostbyname(hostname.characters());
if (!hostent) {
dbgln("Socket::connect: Unable to resolve '{}'", hostname);
return false;
}
// On macOS, the pointer in the hostent structure is misaligned. Load it using ByteReader to avoid UB
auto* host_addr = AK::ByteReader::load_pointer<u8 const>(reinterpret_cast<u8 const*>(&hostent->h_addr_list[0]));
IPv4Address host_address(host_addr);
dbgln_if(CSOCKET_DEBUG, "Socket::connect: Resolved '{}' to {}", hostname, host_address);
return connect(host_address, port);
}
void Socket::set_blocking(bool blocking)
{
int flags = fcntl(fd(), F_GETFL, 0);
VERIFY(flags >= 0);
if (blocking)
flags = fcntl(fd(), F_SETFL, flags & ~O_NONBLOCK);
else
flags = fcntl(fd(), F_SETFL, flags | O_NONBLOCK);
VERIFY(flags == 0);
}
bool Socket::connect(const SocketAddress& address, int port)
{
VERIFY(!is_connected());
VERIFY(address.type() == SocketAddress::Type::IPv4);
dbgln_if(CSOCKET_DEBUG, "{} connecting to {}...", *this, address);
VERIFY(port > 0 && port <= 65535);
struct sockaddr_in addr;
memset(&addr, 0, sizeof(addr));
auto ipv4_address = address.ipv4_address();
memcpy(&addr.sin_addr.s_addr, &ipv4_address, sizeof(IPv4Address));
addr.sin_family = AF_INET;
addr.sin_port = htons(port);
m_destination_address = address;
m_destination_port = port;
return common_connect((struct sockaddr*)&addr, sizeof(addr));
}
bool Socket::connect(const SocketAddress& address)
{
VERIFY(!is_connected());
VERIFY(address.type() == SocketAddress::Type::Local);
dbgln_if(CSOCKET_DEBUG, "{} connecting to {}...", *this, address);
sockaddr_un saddr;
saddr.sun_family = AF_LOCAL;
auto dest_address = address.to_string();
bool fits = dest_address.copy_characters_to_buffer(saddr.sun_path, sizeof(saddr.sun_path));
if (!fits) {
warnln("Core::Socket: Failed to connect() to {}: Path is too long!", dest_address);
errno = EINVAL;
return false;
}
m_destination_address = address;
return common_connect((const sockaddr*)&saddr, sizeof(saddr));
}
bool Socket::common_connect(const struct sockaddr* addr, socklen_t addrlen)
{
auto connected = [this] {
dbgln_if(CSOCKET_DEBUG, "{} connected!", *this);
if (!m_connected) {
m_connected = true;
ensure_read_notifier();
if (m_notifier) {
m_notifier->remove_from_parent();
m_notifier = nullptr;
}
if (on_connected)
on_connected();
}
};
int rc = ::connect(fd(), addr, addrlen);
if (rc < 0) {
if (errno == EINPROGRESS) {
dbgln_if(CSOCKET_DEBUG, "{} connection in progress (EINPROGRESS)", *this);
m_notifier = Notifier::construct(fd(), Notifier::Event::Write, this);
m_notifier->on_ready_to_write = move(connected);
return true;
}
int saved_errno = errno;
warnln("Core::Socket: Failed to connect() to {}: {}", destination_address().to_string(), strerror(saved_errno));
errno = saved_errno;
return false;
}
dbgln_if(CSOCKET_DEBUG, "{} connected ok!", *this);
connected();
return true;
}
ByteBuffer Socket::receive(int max_size)
{
auto buffer = read(max_size);
if (eof())
m_connected = false;
return buffer;
}
bool Socket::send(ReadonlyBytes data)
{
auto remaining_bytes = data.size();
while (remaining_bytes > 0) {
ssize_t nsent = ::send(fd(), data.data() + (data.size() - remaining_bytes), remaining_bytes, 0);
if (nsent < 0) {
set_error(errno);
return false;
}
remaining_bytes -= nsent;
}
return true;
}
void Socket::did_update_fd(int fd)
{
if (fd < 0) {
if (m_read_notifier) {
m_read_notifier->remove_from_parent();
m_read_notifier = nullptr;
}
if (m_notifier) {
m_notifier->remove_from_parent();
m_notifier = nullptr;
}
return;
}
if (m_connected) {
ensure_read_notifier();
} else {
// I don't think it would be right if we updated the fd while not connected *but* while having a notifier..
VERIFY(!m_read_notifier);
}
}
void Socket::ensure_read_notifier()
{
VERIFY(m_connected);
m_read_notifier = Notifier::construct(fd(), Notifier::Event::Read, this);
m_read_notifier->on_ready_to_read = [this] {
if (!can_read())
return;
if (on_ready_to_read)
on_ready_to_read();
};
}
}