Kernel/LibC: Implement getsockname for ipv4 sockets

kernel/include/kernel/FS/Inode.h

@@ -105,6 +105,7 @@ namespace Kernel
 		BAN::ErrorOr<void> listen(int backlog);
 		BAN::ErrorOr<size_t> sendto(BAN::ConstByteSpan message, const sockaddr* address, socklen_t address_len);
 		BAN::ErrorOr<size_t> recvfrom(BAN::ByteSpan buffer, sockaddr* address, socklen_t* address_len);
+		BAN::ErrorOr<void> getsockname(sockaddr* address, socklen_t* address_len);
 
 		// General API
 		BAN::ErrorOr<size_t> read(off_t, BAN::ByteSpan buffer);
@@ -139,7 +140,8 @@ namespace Kernel
 		virtual BAN::ErrorOr<void> listen_impl(int)													{ return BAN::Error::from_errno(ENOTSUP); }
 		virtual BAN::ErrorOr<void> bind_impl(const sockaddr*, socklen_t)							{ return BAN::Error::from_errno(ENOTSUP); }
 		virtual BAN::ErrorOr<size_t> sendto_impl(BAN::ConstByteSpan, const sockaddr*, socklen_t)	{ return BAN::Error::from_errno(ENOTSUP); }
-		virtual BAN::ErrorOr<size_t> recvfrom_impl(BAN::ByteSpan, sockaddr*, socklen_t*)				{ return BAN::Error::from_errno(ENOTSUP); }
+		virtual BAN::ErrorOr<size_t> recvfrom_impl(BAN::ByteSpan, sockaddr*, socklen_t*)			{ return BAN::Error::from_errno(ENOTSUP); }
+		virtual BAN::ErrorOr<void> getsockname_impl(sockaddr*, socklen_t*)							{ return BAN::Error::from_errno(ENOTSUP); }
 
 		// General API
 		virtual BAN::ErrorOr<size_t> read_impl(off_t, BAN::ByteSpan)		{ return BAN::Error::from_errno(ENOTSUP); }

kernel/include/kernel/Networking/IPv4Layer.h

@@ -47,6 +47,7 @@ namespace Kernel
 		virtual void unbind_socket(BAN::RefPtr<NetworkSocket>, uint16_t port) override;
 		virtual BAN::ErrorOr<void> bind_socket_to_unused(BAN::RefPtr<NetworkSocket>, const sockaddr* send_address, socklen_t send_address_len) override;
 		virtual BAN::ErrorOr<void> bind_socket_to_address(BAN::RefPtr<NetworkSocket>, const sockaddr* address, socklen_t address_len) override;
+		virtual BAN::ErrorOr<void> get_socket_address(BAN::RefPtr<NetworkSocket>, sockaddr* address, socklen_t* address_len) override;
 
 		virtual BAN::ErrorOr<size_t> sendto(NetworkSocket&, BAN::ConstByteSpan, const sockaddr*, socklen_t) override;
 

kernel/include/kernel/Networking/NetworkLayer.h

@@ -25,6 +25,7 @@ namespace Kernel
 		virtual void unbind_socket(BAN::RefPtr<NetworkSocket>, uint16_t port) = 0;
 		virtual BAN::ErrorOr<void> bind_socket_to_unused(BAN::RefPtr<NetworkSocket>, const sockaddr* send_address, socklen_t send_address_len) = 0;
 		virtual BAN::ErrorOr<void> bind_socket_to_address(BAN::RefPtr<NetworkSocket>, const sockaddr* address, socklen_t address_len) = 0;
+		virtual BAN::ErrorOr<void> get_socket_address(BAN::RefPtr<NetworkSocket>, sockaddr* address, socklen_t* address_len) = 0;
 
 		virtual BAN::ErrorOr<size_t> sendto(NetworkSocket&, BAN::ConstByteSpan, const sockaddr*, socklen_t) = 0;
 

kernel/include/kernel/Networking/NetworkSocket.h

@@ -42,6 +42,7 @@ namespace Kernel
 		NetworkSocket(NetworkLayer&, ino_t, const TmpInodeInfo&);
 
 		virtual BAN::ErrorOr<long> ioctl_impl(int request, void* arg) override;
+		virtual BAN::ErrorOr<void> getsockname_impl(sockaddr*, socklen_t*) override;
 
 	protected:
 		NetworkLayer&		m_network_layer;

kernel/include/kernel/Process.h

@@ -119,6 +119,8 @@ namespace Kernel
 		BAN::ErrorOr<long> sys_chown(const char*, uid_t, gid_t);
 
 		BAN::ErrorOr<long> sys_socket(int domain, int type, int protocol);
+		BAN::ErrorOr<long> sys_getsockname(int socket, sockaddr* address, socklen_t* address_len);
+
 		BAN::ErrorOr<long> sys_accept(int socket, sockaddr* address, socklen_t* address_len);
 		BAN::ErrorOr<long> sys_bind(int socket, const sockaddr* address, socklen_t address_len);
 		BAN::ErrorOr<long> sys_connect(int socket, const sockaddr* address, socklen_t address_len);

kernel/kernel/FS/Inode.cpp

@@ -164,6 +164,14 @@ namespace Kernel
 		return recvfrom_impl(buffer, address, address_len);
 	};
 
+	BAN::ErrorOr<void> Inode::getsockname(sockaddr* address, socklen_t* address_len)
+	{
+		LockGuard _(m_mutex);
+		if (!mode().ifsock())
+			return BAN::Error::from_errno(ENOTSOCK);
+		return getsockname_impl(address, address_len);
+	}
+
 	BAN::ErrorOr<size_t> Inode::read(off_t offset, BAN::ByteSpan buffer)
 	{
 		LockGuard _(m_mutex);

kernel/kernel/Networking/IPv4Layer.cpp

@@ -139,6 +139,28 @@ namespace Kernel
 		return {};
 	}
 
+	BAN::ErrorOr<void> IPv4Layer::get_socket_address(BAN::RefPtr<NetworkSocket> socket, sockaddr* address, socklen_t* address_len)
+	{
+		if (*address_len < (socklen_t)sizeof(sockaddr_in))
+			return BAN::Error::from_errno(ENOBUFS);
+
+		sockaddr_in* in_addr = reinterpret_cast<sockaddr_in*>(address);
+
+		SpinLockGuard _(m_bound_socket_lock);
+		for (auto& [bound_port, bound_socket] : m_bound_sockets)
+		{
+			if (socket != bound_socket.lock())
+				continue;
+			// FIXME: sockets should have bound address
+			in_addr->sin_family = AF_INET;
+			in_addr->sin_port = bound_port;
+			in_addr->sin_addr.s_addr = INADDR_ANY;
+			return {};
+		}
+
+		return {};
+	}
+
 	BAN::ErrorOr<size_t> IPv4Layer::sendto(NetworkSocket& socket, BAN::ConstByteSpan buffer, const sockaddr* address, socklen_t address_len)
 	{
 		if (address->sa_family != AF_INET)

kernel/kernel/Networking/NetworkSocket.cpp

@@ -100,4 +100,10 @@ namespace Kernel
 		}
 	}
 
+	BAN::ErrorOr<void> NetworkSocket::getsockname_impl(sockaddr* address, socklen_t* address_len)
+	{
+		TRY(m_network_layer.get_socket_address(this, address, address_len));
+		return {};
+	}
+
 }

kernel/kernel/Process.cpp

@@ -911,6 +911,20 @@ namespace Kernel
 		return TRY(m_open_file_descriptors.socket(domain, type, protocol));
 	}
 
+	BAN::ErrorOr<long> Process::sys_getsockname(int socket, sockaddr* address, socklen_t* address_len)
+	{
+		LockGuard _(m_process_lock);
+		TRY(validate_pointer_access(address_len, sizeof(address_len)));
+		TRY(validate_pointer_access(address, *address_len));
+
+		auto inode = TRY(m_open_file_descriptors.inode_of(socket));
+		if (!inode->mode().ifsock())
+			return BAN::Error::from_errno(ENOTSOCK);
+
+		TRY(inode->getsockname(address, address_len));
+		return 0;
+	}
+
 	BAN::ErrorOr<long> Process::sys_accept(int socket, sockaddr* address, socklen_t* address_len)
 	{
 		if (address && !address_len)

libc/include/sys/syscall.h

@@ -78,6 +78,7 @@ __BEGIN_DECLS
 	O(SYS_SMO_DELETE,		smo_delete)		\
 	O(SYS_SMO_MAP,			smo_map)		\
 	O(SYS_ISATTY,			isatty)			\
+	O(SYS_GETSOCKNAME,		getsockname)	\
 
 enum Syscall
 {

libc/sys/socket.cpp

@@ -62,3 +62,8 @@ int socket(int domain, int type, int protocol)
 {
 	return syscall(SYS_SOCKET, domain, type, protocol);
 }
+
+int getsockname(int socket, struct sockaddr* __restrict address, socklen_t* __restrict address_len)
+{
+	return syscall(SYS_GETSOCKNAME, socket, address, address_len);
+}