// Copyright (C) 2016 The Syncthing Authors. // // This Source Code Form is subject to the terms of the Mozilla Public // License, v. 2.0. If a copy of the MPL was not distributed with this file, // You can obtain one at http://mozilla.org/MPL/2.0/. package connections import ( "net" "net/url" "strconv" "strings" "github.com/syncthing/syncthing/lib/osutil" ) func fixupPort(uri *url.URL, defaultPort int) *url.URL { copyURI := *uri host, port, err := net.SplitHostPort(uri.Host) if e, ok := err.(*net.AddrError); ok && strings.Contains(e.Err, "missing port") { // addr is of the form "1.2.3.4" or "[fe80::1]" host = uri.Host if strings.HasPrefix(host, "[") && strings.HasSuffix(host, "]") { // net.JoinHostPort will add the brackets again host = host[1 : len(host)-1] } copyURI.Host = net.JoinHostPort(host, strconv.Itoa(defaultPort)) } else if err == nil && port == "" { // addr is on the form "1.2.3.4:" or "[fe80::1]:" copyURI.Host = net.JoinHostPort(host, strconv.Itoa(defaultPort)) } return ©URI } func getURLsForAllAdaptersIfUnspecified(network string, uri *url.URL) []*url.URL { ip, port, err := resolve(network, uri.Host) // Failed to resolve if err != nil || port == 0 { return nil } // Not an unspecified address, so no point of substituting with local // interface addresses as it's listening on a specific adapter anyway. if len(ip) != 0 && !ip.IsUnspecified() { return nil } hostPorts := getHostPortsForAllAdapters(port) addrs := make([]*url.URL, 0, len(hostPorts)) for _, hostPort := range hostPorts { newUri := *uri newUri.Host = hostPort addrs = append(addrs, &newUri) } return addrs } func getHostPortsForAllAdapters(port int) []string { nets, err := osutil.GetLans() if err != nil { // Ignore failure. return nil } hostPorts := make([]string, 0, len(nets)) portStr := strconv.Itoa(port) for _, network := range nets { // Only accept IPv4 link-local unicast and the private ranges defined in RFC 1918 and RFC 4193 // IPv6 link-local addresses require an interface identifier to work correctly if (network.IP.To4() != nil && network.IP.IsLinkLocalUnicast()) || network.IP.IsPrivate() { hostPorts = append(hostPorts, net.JoinHostPort(network.IP.String(), portStr)) } } return hostPorts } func resolve(network, hostPort string) (net.IP, int, error) { switch network { case "tcp", "tcp4", "tcp6": if addr, err := net.ResolveTCPAddr(network, hostPort); err != nil { return net.IPv4zero, 0, err } else { return addr.IP, addr.Port, nil } case "udp", "udp4", "udp6": if addr, err := net.ResolveUDPAddr(network, hostPort); err != nil { return net.IPv4zero, 0, err } else { return addr.IP, addr.Port, nil } case "ip", "ip4", "ip6": if addr, err := net.ResolveIPAddr(network, hostPort); err != nil { return net.IPv4zero, 0, err } else { return addr.IP, 0, nil } } return net.IPv4zero, 0, net.UnknownNetworkError(network) } func maybeReplacePort(uri *url.URL, laddr net.Addr) *url.URL { if laddr == nil { return uri } host, portStr, err := net.SplitHostPort(uri.Host) if err != nil { return uri } port, err := strconv.Atoi(portStr) if err != nil { return uri } if port != 0 { return uri } _, lportStr, err := net.SplitHostPort(laddr.String()) if err != nil { return uri } uriCopy := *uri uriCopy.Host = net.JoinHostPort(host, lportStr) return &uriCopy }