diff options
Diffstat (limited to 'vendor/golang.org/x/net/ipv4/control_unix.go')
-rw-r--r-- | vendor/golang.org/x/net/ipv4/control_unix.go | 164 |
1 files changed, 164 insertions, 0 deletions
diff --git a/vendor/golang.org/x/net/ipv4/control_unix.go b/vendor/golang.org/x/net/ipv4/control_unix.go new file mode 100644 index 000000000..6b6682d65 --- /dev/null +++ b/vendor/golang.org/x/net/ipv4/control_unix.go @@ -0,0 +1,164 @@ +// Copyright 2012 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +// +build darwin dragonfly freebsd linux netbsd openbsd + +package ipv4 + +import ( + "os" + "syscall" + "unsafe" + + "golang.org/x/net/internal/iana" +) + +func setControlMessage(s uintptr, opt *rawOpt, cf ControlFlags, on bool) error { + opt.Lock() + defer opt.Unlock() + if cf&FlagTTL != 0 && sockOpts[ssoReceiveTTL].name > 0 { + if err := setInt(s, &sockOpts[ssoReceiveTTL], boolint(on)); err != nil { + return err + } + if on { + opt.set(FlagTTL) + } else { + opt.clear(FlagTTL) + } + } + if sockOpts[ssoPacketInfo].name > 0 { + if cf&(FlagSrc|FlagDst|FlagInterface) != 0 { + if err := setInt(s, &sockOpts[ssoPacketInfo], boolint(on)); err != nil { + return err + } + if on { + opt.set(cf & (FlagSrc | FlagDst | FlagInterface)) + } else { + opt.clear(cf & (FlagSrc | FlagDst | FlagInterface)) + } + } + } else { + if cf&FlagDst != 0 && sockOpts[ssoReceiveDst].name > 0 { + if err := setInt(s, &sockOpts[ssoReceiveDst], boolint(on)); err != nil { + return err + } + if on { + opt.set(FlagDst) + } else { + opt.clear(FlagDst) + } + } + if cf&FlagInterface != 0 && sockOpts[ssoReceiveInterface].name > 0 { + if err := setInt(s, &sockOpts[ssoReceiveInterface], boolint(on)); err != nil { + return err + } + if on { + opt.set(FlagInterface) + } else { + opt.clear(FlagInterface) + } + } + } + return nil +} + +func newControlMessage(opt *rawOpt) (oob []byte) { + opt.RLock() + var l int + if opt.isset(FlagTTL) && ctlOpts[ctlTTL].name > 0 { + l += syscall.CmsgSpace(ctlOpts[ctlTTL].length) + } + if ctlOpts[ctlPacketInfo].name > 0 { + if opt.isset(FlagSrc | FlagDst | FlagInterface) { + l += syscall.CmsgSpace(ctlOpts[ctlPacketInfo].length) + } + } else { + if opt.isset(FlagDst) && ctlOpts[ctlDst].name > 0 { + l += syscall.CmsgSpace(ctlOpts[ctlDst].length) + } + if opt.isset(FlagInterface) && ctlOpts[ctlInterface].name > 0 { + l += syscall.CmsgSpace(ctlOpts[ctlInterface].length) + } + } + if l > 0 { + oob = make([]byte, l) + b := oob + if opt.isset(FlagTTL) && ctlOpts[ctlTTL].name > 0 { + b = ctlOpts[ctlTTL].marshal(b, nil) + } + if ctlOpts[ctlPacketInfo].name > 0 { + if opt.isset(FlagSrc | FlagDst | FlagInterface) { + b = ctlOpts[ctlPacketInfo].marshal(b, nil) + } + } else { + if opt.isset(FlagDst) && ctlOpts[ctlDst].name > 0 { + b = ctlOpts[ctlDst].marshal(b, nil) + } + if opt.isset(FlagInterface) && ctlOpts[ctlInterface].name > 0 { + b = ctlOpts[ctlInterface].marshal(b, nil) + } + } + } + opt.RUnlock() + return +} + +func parseControlMessage(b []byte) (*ControlMessage, error) { + if len(b) == 0 { + return nil, nil + } + cmsgs, err := syscall.ParseSocketControlMessage(b) + if err != nil { + return nil, os.NewSyscallError("parse socket control message", err) + } + cm := &ControlMessage{} + for _, m := range cmsgs { + if m.Header.Level != iana.ProtocolIP { + continue + } + switch int(m.Header.Type) { + case ctlOpts[ctlTTL].name: + ctlOpts[ctlTTL].parse(cm, m.Data[:]) + case ctlOpts[ctlDst].name: + ctlOpts[ctlDst].parse(cm, m.Data[:]) + case ctlOpts[ctlInterface].name: + ctlOpts[ctlInterface].parse(cm, m.Data[:]) + case ctlOpts[ctlPacketInfo].name: + ctlOpts[ctlPacketInfo].parse(cm, m.Data[:]) + } + } + return cm, nil +} + +func marshalControlMessage(cm *ControlMessage) (oob []byte) { + if cm == nil { + return nil + } + var l int + pktinfo := false + if ctlOpts[ctlPacketInfo].name > 0 && (cm.Src.To4() != nil || cm.IfIndex > 0) { + pktinfo = true + l += syscall.CmsgSpace(ctlOpts[ctlPacketInfo].length) + } + if l > 0 { + oob = make([]byte, l) + b := oob + if pktinfo { + b = ctlOpts[ctlPacketInfo].marshal(b, cm) + } + } + return +} + +func marshalTTL(b []byte, cm *ControlMessage) []byte { + m := (*syscall.Cmsghdr)(unsafe.Pointer(&b[0])) + m.Level = iana.ProtocolIP + m.Type = sysIP_RECVTTL + m.SetLen(syscall.CmsgLen(1)) + return b[syscall.CmsgSpace(1):] +} + +func parseTTL(cm *ControlMessage, b []byte) { + cm.TTL = int(*(*byte)(unsafe.Pointer(&b[:1][0]))) +} |