Method set_ip_addr

net_util/src/tap.rs:298–363

Set the host-side IP address for the tap interface.

(&self, ip_addr: IpAddr, netmask: Option<IpAddr>)

    /// Set the host-side IP address for the tap interface.
    pub fn set_ip_addr(&self, ip_addr: IpAddr, netmask: Option<IpAddr>) -> Result<()> {
        let sock = create_inet_socket(ip_addr).map_err(Error::NetUtil)?;

        let mut ifreq = self.get_ifreq();

        match ip_addr {
            IpAddr::V4(addr) => {
                let addr = create_sockaddr(addr);

                ifreq.ifr_ifru.ifru_addr = addr;

                // SAFETY: ioctl is safe. Called with a valid sock fd, and we check the return.
                unsafe {
                    Self::ioctl_with_ref(&sock, libc::SIOCSIFADDR as c_ulong, &ifreq)?;
                }

                if let Some(IpAddr::V4(mask)) = netmask {
                    ifreq.ifr_ifru.ifru_netmask = create_sockaddr(mask);

                    // SAFETY: ioctl is safe. Called with a valid sock fd, and we check the return.
                    unsafe {
                        Self::ioctl_with_ref(&sock, libc::SIOCSIFNETMASK as c_ulong, &ifreq)?;
                    }
                }

                Ok(())
            }
            IpAddr::V6(addr) => {
                let ifindex = {
                    // SAFETY: ioctl is safe. Called with a valid sock fd, and we check the return.
                    unsafe {
                        Self::ioctl_with_ref(&sock, libc::SIOCGIFINDEX as c_ulong, &ifreq)?;
                    }

                    // SAFETY: ifru_ivalue contains the ifindex and is set by the previous ioctl
                    unsafe {
                        match ifreq.ifr_ifru.ifru_ifindex {
                            0 => {
                                let name = self.if_name.to_string_lossy().to_string();
                                return Err(Error::InvalidIfname(name));
                            }
                            i => i,
                        }
                    }
                };

                let prefixlen = match netmask {
                    Some(IpAddr::V6(netmask)) => ipv6_mask_to_prefix(netmask)?,
                    Some(IpAddr::V4(_)) => return Err(Error::InvalidNetmask),
                    None => 0,
                };

                let ifreq = libc::in6_ifreq {
                    // SAFETY: addr can be safely transmuted to in6_addr
                    ifr6_addr: unsafe {
                        std::mem::transmute::<[u8; 16], libc::in6_addr>(addr.octets())
                    },
                    ifr6_prefixlen: prefixlen as u32,