1// Take a look at the license at the top of the repository in the LICENSE file.
2
3use crate::common::MacAddr;
4use std::ptr::null_mut;
5
6/// This iterator yields an interface name and address.
7pub(crate) struct InterfaceAddressIterator {
8 /// Pointer to the current `ifaddrs` struct.
9 ifap: *mut libc::ifaddrs,
10 /// Pointer to the first element in linked list.
11 buf: *mut libc::ifaddrs,
12}
13
14impl Iterator for InterfaceAddressIterator {
15 type Item = (String, MacAddr);
16
17 fn next(&mut self) -> Option<Self::Item> {
18 unsafe {
19 while !self.ifap.is_null() {
20 // advance the pointer until a MAC address is found
21 let ifap = self.ifap;
22 self.ifap = (*ifap).ifa_next;
23
24 if let Some(addr) = parse_interface_address(ifap) {
25 // libc::IFNAMSIZ + 6
26 // This size refers to ./apple/network.rs:75
27 let mut name = vec![0u8; libc::IFNAMSIZ + 6];
28 libc::strcpy(name.as_mut_ptr() as _, (*ifap).ifa_name);
29 name.set_len(libc::strlen((*ifap).ifa_name));
30 let name = String::from_utf8_unchecked(name);
31
32 return Some((name, addr));
33 }
34 }
35 None
36 }
37 }
38}
39
40impl Drop for InterfaceAddressIterator {
41 fn drop(&mut self) {
42 unsafe {
43 libc::freeifaddrs(self.buf);
44 }
45 }
46}
47
48#[cfg(any(target_os = "macos", target_os = "freebsd", target_os = "ios"))]
49impl From<&libc::sockaddr_dl> for MacAddr {
50 fn from(value: &libc::sockaddr_dl) -> Self {
51 let sdl_data = value.sdl_data;
52 // interface name length, NO trailing 0
53 let sdl_nlen = value.sdl_nlen as usize;
54 // make sure that it is never out of bound
55 if sdl_nlen + 5 < 12 {
56 MacAddr([
57 sdl_data[sdl_nlen] as u8,
58 sdl_data[sdl_nlen + 1] as u8,
59 sdl_data[sdl_nlen + 2] as u8,
60 sdl_data[sdl_nlen + 3] as u8,
61 sdl_data[sdl_nlen + 4] as u8,
62 sdl_data[sdl_nlen + 5] as u8,
63 ])
64 } else {
65 MacAddr::UNSPECIFIED
66 }
67 }
68}
69
70#[cfg(any(target_os = "macos", target_os = "freebsd", target_os = "ios"))]
71unsafe fn parse_interface_address(ifap: *const libc::ifaddrs) -> Option<MacAddr> {
72 let sock_addr = (*ifap).ifa_addr;
73 if sock_addr.is_null() {
74 return None;
75 }
76 match (*sock_addr).sa_family as libc::c_int {
77 libc::AF_LINK => {
78 let addr = sock_addr as *const libc::sockaddr_dl;
79 Some(MacAddr::from(&*addr))
80 }
81 _ => None,
82 }
83}
84
85#[cfg(any(target_os = "linux", target_os = "android"))]
86unsafe fn parse_interface_address(ifap: *const libc::ifaddrs) -> Option<MacAddr> {
87 use libc::sockaddr_ll;
88
89 let sock_addr: *mut sockaddr = (*ifap).ifa_addr;
90 if sock_addr.is_null() {
91 return None;
92 }
93 match (*sock_addr).sa_family as libc::c_int {
94 libc::AF_PACKET => {
95 let addr: *const sockaddr_ll = sock_addr as *const sockaddr_ll;
96 // Take the first 6 bytes
97 let [addr: [u8; 6] @ .., _, _] = (*addr).sll_addr;
98 Some(MacAddr(addr))
99 }
100 _ => None,
101 }
102}
103
104/// Return an iterator on (interface_name, address) pairs
105pub(crate) fn get_interface_address() -> Result<InterfaceAddressIterator, String> {
106 let mut ifap: *mut ifaddrs = null_mut();
107 unsafe {
108 if retry_eintr!(libc::getifaddrs(&mut ifap)) == 0 && !ifap.is_null() {
109 Ok(InterfaceAddressIterator { ifap, buf: ifap })
110 } else {
111 Err("failed to call getifaddrs()".to_string())
112 }
113 }
114}
115