diff options
Diffstat (limited to 'vendor/github.com/rsc/letsencrypt/vendor/github.com/miekg/dns/udp_linux.go')
-rw-r--r-- | vendor/github.com/rsc/letsencrypt/vendor/github.com/miekg/dns/udp_linux.go | 105 |
1 files changed, 0 insertions, 105 deletions
diff --git a/vendor/github.com/rsc/letsencrypt/vendor/github.com/miekg/dns/udp_linux.go b/vendor/github.com/rsc/letsencrypt/vendor/github.com/miekg/dns/udp_linux.go deleted file mode 100644 index 033df4239..000000000 --- a/vendor/github.com/rsc/letsencrypt/vendor/github.com/miekg/dns/udp_linux.go +++ /dev/null @@ -1,105 +0,0 @@ -// +build linux,!appengine - -package dns - -// See: -// * http://stackoverflow.com/questions/3062205/setting-the-source-ip-for-a-udp-socket and -// * http://blog.powerdns.com/2012/10/08/on-binding-datagram-udp-sockets-to-the-any-addresses/ -// -// Why do we need this: When listening on 0.0.0.0 with UDP so kernel decides what is the outgoing -// interface, this might not always be the correct one. This code will make sure the egress -// packet's interface matched the ingress' one. - -import ( - "net" - "syscall" -) - -// setUDPSocketOptions sets the UDP socket options. -// This function is implemented on a per platform basis. See udp_*.go for more details -func setUDPSocketOptions(conn *net.UDPConn) error { - sa, err := getUDPSocketName(conn) - if err != nil { - return err - } - switch sa.(type) { - case *syscall.SockaddrInet6: - v6only, err := getUDPSocketOptions6Only(conn) - if err != nil { - return err - } - setUDPSocketOptions6(conn) - if !v6only { - setUDPSocketOptions4(conn) - } - case *syscall.SockaddrInet4: - setUDPSocketOptions4(conn) - } - return nil -} - -// setUDPSocketOptions4 prepares the v4 socket for sessions. -func setUDPSocketOptions4(conn *net.UDPConn) error { - file, err := conn.File() - if err != nil { - return err - } - if err := syscall.SetsockoptInt(int(file.Fd()), syscall.IPPROTO_IP, syscall.IP_PKTINFO, 1); err != nil { - file.Close() - return err - } - // Calling File() above results in the connection becoming blocking, we must fix that. - // See https://github.com/miekg/dns/issues/279 - err = syscall.SetNonblock(int(file.Fd()), true) - if err != nil { - file.Close() - return err - } - file.Close() - return nil -} - -// setUDPSocketOptions6 prepares the v6 socket for sessions. -func setUDPSocketOptions6(conn *net.UDPConn) error { - file, err := conn.File() - if err != nil { - return err - } - if err := syscall.SetsockoptInt(int(file.Fd()), syscall.IPPROTO_IPV6, syscall.IPV6_RECVPKTINFO, 1); err != nil { - file.Close() - return err - } - err = syscall.SetNonblock(int(file.Fd()), true) - if err != nil { - file.Close() - return err - } - file.Close() - return nil -} - -// getUDPSocketOption6Only return true if the socket is v6 only and false when it is v4/v6 combined -// (dualstack). -func getUDPSocketOptions6Only(conn *net.UDPConn) (bool, error) { - file, err := conn.File() - if err != nil { - return false, err - } - // dual stack. See http://stackoverflow.com/questions/1618240/how-to-support-both-ipv4-and-ipv6-connections - v6only, err := syscall.GetsockoptInt(int(file.Fd()), syscall.IPPROTO_IPV6, syscall.IPV6_V6ONLY) - if err != nil { - file.Close() - return false, err - } - file.Close() - return v6only == 1, nil -} - -func getUDPSocketName(conn *net.UDPConn) (syscall.Sockaddr, error) { - file, err := conn.File() - if err != nil { - return nil, err - } - defer file.Close() - return syscall.Getsockname(int(file.Fd())) -} |