|
| 1 | +use std::{io, net::SocketAddr}; |
| 2 | + |
| 3 | +/// Convert from `libc::sockaddr_storage` to `std::net::SocketAddr` |
| 4 | +#[allow(unsafe_code)] |
| 5 | +pub fn socket_addr_from_sockaddr( |
| 6 | + storage: &libc::sockaddr_storage, |
| 7 | + len: libc::socklen_t, |
| 8 | +) -> io::Result<SocketAddr> { |
| 9 | + match storage.ss_family as libc::c_int { |
| 10 | + libc::AF_INET => { |
| 11 | + if (len as usize) < std::mem::size_of::<libc::sockaddr_in>() { |
| 12 | + return Err(io::Error::new( |
| 13 | + io::ErrorKind::InvalidInput, |
| 14 | + "invalid argument (inet len)", |
| 15 | + )); |
| 16 | + } |
| 17 | + |
| 18 | + // SAFETY: Casting from sockaddr_storage to sockaddr_in is safe since we have validated the len. |
| 19 | + let addr = |
| 20 | + unsafe { &*(storage as *const libc::sockaddr_storage as *const libc::sockaddr_in) }; |
| 21 | + |
| 22 | + let ip = u32::from_be(addr.sin_addr.s_addr); |
| 23 | + let ip = std::net::Ipv4Addr::from_bits(ip); |
| 24 | + let port = u16::from_be(addr.sin_port); |
| 25 | + |
| 26 | + Ok((ip, port).into()) |
| 27 | + } |
| 28 | + libc::AF_INET6 => { |
| 29 | + if (len as usize) < std::mem::size_of::<libc::sockaddr_in6>() { |
| 30 | + return Err(io::Error::new( |
| 31 | + io::ErrorKind::InvalidInput, |
| 32 | + "invalid argument (inet6 len)", |
| 33 | + )); |
| 34 | + } |
| 35 | + // SAFETY: Casting from sockaddr_storage to sockaddr_in6 is safe since we have validated the len. |
| 36 | + let addr = unsafe { |
| 37 | + &*(storage as *const libc::sockaddr_storage as *const libc::sockaddr_in6) |
| 38 | + }; |
| 39 | + |
| 40 | + let ip = u128::from_be_bytes(addr.sin6_addr.s6_addr); |
| 41 | + let ip = std::net::Ipv6Addr::from_bits(ip); |
| 42 | + let port = u16::from_be(addr.sin6_port); |
| 43 | + |
| 44 | + Ok((ip, port).into()) |
| 45 | + } |
| 46 | + _ => Err(io::Error::new( |
| 47 | + std::io::ErrorKind::InvalidInput, |
| 48 | + "invalid argument (ss_family)", |
| 49 | + )), |
| 50 | + } |
| 51 | +} |
| 52 | + |
| 53 | +/// Convert from `std::net::SocketAddr` to `libc::sockaddr_storage`+`libc::socklen_t` |
| 54 | +#[allow(unsafe_code)] |
| 55 | +pub fn sockaddr_from_socket_addr(addr: SocketAddr) -> (libc::sockaddr_storage, libc::socklen_t) { |
| 56 | + // SAFETY: All zeroes is a valid sockaddr_storage |
| 57 | + let mut storage: libc::sockaddr_storage = unsafe { std::mem::zeroed() }; |
| 58 | + |
| 59 | + let len = match addr { |
| 60 | + SocketAddr::V4(v4) => { |
| 61 | + let p = &mut storage as *mut libc::sockaddr_storage as *mut libc::sockaddr_in; |
| 62 | + // SAFETY: sockaddr_storage is defined to be big enough for any sockaddr_*. |
| 63 | + unsafe { |
| 64 | + p.write(libc::sockaddr_in { |
| 65 | + sin_family: libc::AF_INET as _, |
| 66 | + sin_port: v4.port().to_be(), |
| 67 | + sin_addr: libc::in_addr { |
| 68 | + s_addr: v4.ip().to_bits().to_be(), |
| 69 | + }, |
| 70 | + sin_zero: Default::default(), |
| 71 | + }) |
| 72 | + }; |
| 73 | + std::mem::size_of::<libc::sockaddr_in>() as libc::socklen_t |
| 74 | + } |
| 75 | + SocketAddr::V6(v6) => { |
| 76 | + let p = &mut storage as *mut libc::sockaddr_storage as *mut libc::sockaddr_in6; |
| 77 | + // SAFETY: sockaddr_storage is defined to be big enough for any sockaddr_*. |
| 78 | + unsafe { |
| 79 | + p.write(libc::sockaddr_in6 { |
| 80 | + sin6_family: libc::AF_INET6 as _, |
| 81 | + sin6_port: v6.port().to_be(), |
| 82 | + sin6_flowinfo: v6.flowinfo().to_be(), |
| 83 | + sin6_addr: libc::in6_addr { |
| 84 | + s6_addr: v6.ip().to_bits().to_be_bytes(), |
| 85 | + }, |
| 86 | + sin6_scope_id: v6.scope_id().to_be(), |
| 87 | + }) |
| 88 | + }; |
| 89 | + std::mem::size_of::<libc::sockaddr_in6>() as libc::socklen_t |
| 90 | + } |
| 91 | + }; |
| 92 | + |
| 93 | + (storage, len) |
| 94 | +} |
| 95 | + |
| 96 | +#[cfg(test)] |
| 97 | +mod tests { |
| 98 | + #![allow(unsafe_code, clippy::undocumented_unsafe_blocks)] |
| 99 | + |
| 100 | + use std::{ |
| 101 | + net::{IpAddr, Ipv4Addr, Ipv6Addr}, |
| 102 | + str::FromStr as _, |
| 103 | + }; |
| 104 | + |
| 105 | + use super::*; |
| 106 | + |
| 107 | + use test_case::test_case; |
| 108 | + |
| 109 | + #[test] |
| 110 | + fn socket_addr_from_sockaddr_unknown_af() { |
| 111 | + // Test assumes these don't match the zero initialized |
| 112 | + // libc::sockaddr_storage::ss_family. |
| 113 | + assert_ne!(libc::AF_INET, 0); |
| 114 | + assert_ne!(libc::AF_INET6, 0); |
| 115 | + |
| 116 | + let storage = unsafe { std::mem::zeroed() }; |
| 117 | + let err = |
| 118 | + socket_addr_from_sockaddr(&storage, std::mem::size_of::<libc::sockaddr_storage>() as _) |
| 119 | + .unwrap_err(); |
| 120 | + |
| 121 | + assert!(matches!(err.kind(), std::io::ErrorKind::InvalidInput)); |
| 122 | + assert!(err.to_string().contains("invalid argument (ss_family)")); |
| 123 | + } |
| 124 | + |
| 125 | + #[test] |
| 126 | + fn socket_addr_from_sockaddr_unknown_af_inet_short() { |
| 127 | + let mut storage: libc::sockaddr_storage = unsafe { std::mem::zeroed() }; |
| 128 | + storage.ss_family = libc::AF_INET as libc::sa_family_t; |
| 129 | + |
| 130 | + let err = socket_addr_from_sockaddr( |
| 131 | + &storage, |
| 132 | + (std::mem::size_of::<libc::sockaddr_in>() - 1) as _, |
| 133 | + ) |
| 134 | + .unwrap_err(); |
| 135 | + |
| 136 | + assert!(matches!(err.kind(), std::io::ErrorKind::InvalidInput)); |
| 137 | + assert!(err.to_string().contains("invalid argument (inet len)")); |
| 138 | + } |
| 139 | + |
| 140 | + #[test] |
| 141 | + fn socket_addr_from_sockaddr_unknown_af_inet6_short() { |
| 142 | + let mut storage: libc::sockaddr_storage = unsafe { std::mem::zeroed() }; |
| 143 | + storage.ss_family = libc::AF_INET6 as libc::sa_family_t; |
| 144 | + |
| 145 | + let err = socket_addr_from_sockaddr( |
| 146 | + &storage, |
| 147 | + (std::mem::size_of::<libc::sockaddr_in6>() - 1) as _, |
| 148 | + ) |
| 149 | + .unwrap_err(); |
| 150 | + |
| 151 | + assert!(matches!(err.kind(), std::io::ErrorKind::InvalidInput)); |
| 152 | + assert!(err.to_string().contains("invalid argument (inet6 len)")); |
| 153 | + } |
| 154 | + |
| 155 | + #[test] |
| 156 | + fn sockaddr_from_socket_addr_inet() { |
| 157 | + let socket_addr = SocketAddr::new(IpAddr::V4(Ipv4Addr::new(127, 0, 0, 1)), 8080); |
| 158 | + let (storage, len) = sockaddr_from_socket_addr(socket_addr); |
| 159 | + assert_eq!(storage.ss_family, libc::AF_INET as libc::sa_family_t); |
| 160 | + assert_eq!(len as usize, std::mem::size_of::<libc::sockaddr_in>()); |
| 161 | + } |
| 162 | + |
| 163 | + #[test] |
| 164 | + fn sockaddr_from_socket_addr_inet6() { |
| 165 | + let socket_addr = SocketAddr::new(IpAddr::V6(Ipv6Addr::new(0, 0, 0, 0, 0, 0, 0, 1)), 8080); |
| 166 | + let (storage, len) = sockaddr_from_socket_addr(socket_addr); |
| 167 | + assert_eq!(storage.ss_family, libc::AF_INET6 as libc::sa_family_t); |
| 168 | + assert_eq!(len as usize, std::mem::size_of::<libc::sockaddr_in6>()); |
| 169 | + } |
| 170 | + |
| 171 | + #[test_case("127.0.0.1:443")] |
| 172 | + #[test_case("[::1]:8888")] |
| 173 | + fn round_trip(addr: &str) { |
| 174 | + let orig = SocketAddr::from_str(addr).unwrap(); |
| 175 | + let (storage, len) = sockaddr_from_socket_addr(orig); |
| 176 | + let round_tripped = socket_addr_from_sockaddr(&storage, len).unwrap(); |
| 177 | + assert_eq!(orig, round_tripped) |
| 178 | + } |
| 179 | +} |
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