// Copyright 2018 Amazon.com, Inc. or its affiliates. All Rights Reserved. // SPDX-License-Identifier: Apache-2.0 // // Portions Copyright 2017 The Chromium OS Authors. All rights reserved. // Use of this source code is governed by a BSD-style license that can be // found in the THIRD-PARTY file. // This is only used by the tests module from tap.rs, but we cannot use #[macro_use] unless the // reference to lazy_static is declared at the root level of the importing crate. #[cfg(test)] #[macro_use] extern crate lazy_static; extern crate libc; extern crate rand; extern crate serde; extern crate net_gen; extern crate vmm_sys_util; mod mac; mod tap; use std::io::Error as IoError; use std::mem; use std::net; use std::os::unix::io::FromRawFd; pub use mac::{MacAddr, MAC_ADDR_LEN}; pub use tap::{Error as TapError, Tap}; #[derive(Debug)] pub enum Error { /// Failed to create a socket. CreateSocket(IoError), } pub type Result = std::result::Result; /// Create a sockaddr_in from an IPv4 address, and expose it as /// an opaque sockaddr suitable for usage by socket ioctls. fn create_sockaddr(ip_addr: net::Ipv4Addr) -> net_gen::sockaddr { // IPv4 addresses big-endian (network order), but Ipv4Addr will give us // a view of those bytes directly so we can avoid any endian trickiness. let addr_in = net_gen::sockaddr_in { sin_family: net_gen::AF_INET as u16, sin_port: 0, sin_addr: unsafe { mem::transmute(ip_addr.octets()) }, __pad: [0; 8usize], }; unsafe { mem::transmute(addr_in) } } fn create_socket() -> Result { // This is safe since we check the return value. let sock = unsafe { libc::socket(libc::AF_INET, libc::SOCK_DGRAM, 0) }; if sock < 0 { return Err(Error::CreateSocket(IoError::last_os_error())); } // This is safe; nothing else will use or hold onto the raw sock fd. Ok(unsafe { net::UdpSocket::from_raw_fd(sock) }) } #[cfg(test)] mod tests { use super::*; #[test] fn test_create_sockaddr() { let addr: net::Ipv4Addr = "10.0.0.1".parse().unwrap(); let sockaddr = create_sockaddr(addr); assert_eq!(sockaddr.sa_family, net_gen::AF_INET as u16); let data = &sockaddr.sa_data[..]; // The first two bytes should represent the port, which is 0. assert_eq!(data[0], 0); assert_eq!(data[1], 0); // The next four bytes should represent the actual IPv4 address, in network order. assert_eq!(data[2], 10); assert_eq!(data[3], 0); assert_eq!(data[4], 0); assert_eq!(data[5], 1); } }