Kernel: Truncate addresses stored by getsockname() and getpeername()

If there's not enough space in the output buffer for the whole sockaddr
we now simply truncate the address instead of returning EINVAL.

This patch also makes getpeername() actually return the peer address
rather than the local address.. :^)

Kernel/Net/IPv4Socket.cpp

@@ -82,30 +82,18 @@ IPv4Socket::~IPv4Socket()
  all_sockets().resource().remove(this);
 }
 
-bool IPv4Socket::get_local_address(sockaddr* address, socklen_t* address_size)
+void IPv4Socket::get_local_address(sockaddr* address, socklen_t* address_size)
 {
- // FIXME: Look into what fallback behavior we should have here.
- if (*address_size < sizeof(sockaddr_in))
- return false;
- auto& ia = (sockaddr_in&)*address;
- ia.sin_family = AF_INET;
- ia.sin_port = htons(m_local_port);
- memcpy(&ia.sin_addr, &m_local_address, sizeof(IPv4Address));
+ sockaddr_in local_address = { AF_INET, htons(m_local_port), { m_local_address.to_in_addr_t() }, { 0 } };
+ memcpy(address, &local_address, min(static_cast<size_t>(*address_size), sizeof(sockaddr_in)));
  *address_size = sizeof(sockaddr_in);
- return true;
 }
 
-bool IPv4Socket::get_peer_address(sockaddr* address, socklen_t* address_size)
+void IPv4Socket::get_peer_address(sockaddr* address, socklen_t* address_size)
 {
- // FIXME: Look into what fallback behavior we should have here.
- if (*address_size < sizeof(sockaddr_in))
- return false;
- auto& ia = (sockaddr_in&)*address;
- ia.sin_family = AF_INET;
- ia.sin_port = htons(m_peer_port);
- memcpy(&ia.sin_addr, &m_peer_address, sizeof(IPv4Address));
+ sockaddr_in peer_address = { AF_INET, htons(m_peer_port), { m_peer_address.to_in_addr_t() }, { 0 } };
+ memcpy(address, &peer_address, min(static_cast<size_t>(*address_size), sizeof(sockaddr_in)));
  *address_size = sizeof(sockaddr_in);
- return true;
 }
 
 KResult IPv4Socket::bind(const sockaddr* user_address, socklen_t address_size)

Kernel/Net/IPv4Socket.h

@@ -49,8 +49,8 @@ class IPv4Socket : public Socket {
  virtual KResult bind(const sockaddr*, socklen_t) override;
  virtual KResult connect(FileDescription&, const sockaddr*, socklen_t, ShouldBlock = ShouldBlock::Yes) override;
  virtual KResult listen(int) override;
- virtual bool get_local_address(sockaddr*, socklen_t*) override;
- virtual bool get_peer_address(sockaddr*, socklen_t*) override;
+ virtual void get_local_address(sockaddr*, socklen_t*) override;
+ virtual void get_peer_address(sockaddr*, socklen_t*) override;
  virtual void attach(FileDescription&) override;
  virtual void detach(FileDescription&) override;
  virtual bool can_read(const FileDescription&) const override;

Kernel/Net/LocalSocket.cpp

@@ -76,19 +76,16 @@ LocalSocket::~LocalSocket()
  all_sockets().resource().remove(this);
 }
 
-bool LocalSocket::get_local_address(sockaddr* address, socklen_t* address_size)
+void LocalSocket::get_local_address(sockaddr* address, socklen_t* address_size)
 {
- // FIXME: Look into what fallback behavior we should have here.
- if (*address_size != sizeof(sockaddr_un))
- return false;
- memcpy(address, &m_address, sizeof(sockaddr_un));
+ size_t bytes_to_copy = min(static_cast<size_t>(*address_size), sizeof(sockaddr_un));
+ memcpy(address, &m_address, bytes_to_copy);
  *address_size = sizeof(sockaddr_un);
- return true;
 }
 
-bool LocalSocket::get_peer_address(sockaddr* address, socklen_t* address_size)
+void LocalSocket::get_peer_address(sockaddr* address, socklen_t* address_size)
 {
- return get_local_address(address, address_size);
+ get_local_address(address, address_size);
 }
 
 KResult LocalSocket::bind(const sockaddr* user_address, socklen_t address_size)

Kernel/Net/LocalSocket.h

@@ -47,8 +47,8 @@ class LocalSocket final : public Socket, public InlineLinkedListNode<LocalSocket
  virtual KResult bind(const sockaddr*, socklen_t) override;
  virtual KResult connect(FileDescription&, const sockaddr*, socklen_t, ShouldBlock = ShouldBlock::Yes) override;
  virtual KResult listen(int) override;
- virtual bool get_local_address(sockaddr*, socklen_t*) override;
- virtual bool get_peer_address(sockaddr*, socklen_t*) override;
+ virtual void get_local_address(sockaddr*, socklen_t*) override;
+ virtual void get_peer_address(sockaddr*, socklen_t*) override;
  virtual void attach(FileDescription&) override;
  virtual void detach(FileDescription&) override;
  virtual bool can_read(const FileDescription&) const override;

Kernel/Net/Socket.h

@@ -93,8 +93,8 @@ class Socket : public File {
  virtual KResult bind(const sockaddr*, socklen_t) = 0;
  virtual KResult connect(FileDescription&, const sockaddr*, socklen_t, ShouldBlock) = 0;
  virtual KResult listen(int) = 0;
- virtual bool get_local_address(sockaddr*, socklen_t*) = 0;
- virtual bool get_peer_address(sockaddr*, socklen_t*) = 0;
+ virtual void get_local_address(sockaddr*, socklen_t*) = 0;
+ virtual void get_peer_address(sockaddr*, socklen_t*) = 0;
  virtual bool is_local() const { return false; }
  virtual bool is_ipv4() const { return false; }
  virtual void attach(FileDescription&) = 0;

Kernel/Process.cpp

@@ -3190,8 +3190,7 @@ int Process::sys$accept(int accepting_socket_fd, sockaddr* address, socklen_t* a
  }
  auto accepted_socket = socket.accept();
  ASSERT(accepted_socket);
- bool success = accepted_socket->get_peer_address(address, address_size);
- ASSERT(success);
+ accepted_socket->get_peer_address(address, address_size);
  auto accepted_socket_description = FileDescription::create(*accepted_socket);
  accepted_socket_description->set_readable(true);
  accepted_socket_description->set_writable(true);
@@ -3318,11 +3317,12 @@ int Process::get_sock_or_peer_name(const Params& params)
 
  u8 address_buffer[sizeof(sockaddr_un)];
  addrlen_value = min(sizeof(sockaddr_un), static_cast<size_t>(addrlen_value));
-
- if (!socket.get_local_address((sockaddr*)address_buffer, &addrlen_value))
-  return -EINVAL;
-
+ if constexpr (sockname)
+  socket.get_local_address((sockaddr*)address_buffer, &addrlen_value);
+ else
+ socket.get_peer_address((sockaddr*)address_buffer, &addrlen_value);
  copy_to_user(params.addr, address_buffer, addrlen_value);
+ copy_to_user(params.addrlen, &addrlen_value);
  return 0;
 }