syscall: add network interface announce support on BSD variants

This CL allows to receive network interface arrival and depature
notifications through routing sockets on BSD variants. So far
Darwin doesn't support this feature.

Also does small simplification.

Update #4866.

R=golang-dev, lucio.dere, dave
CC=golang-dev
https://golang.org/cl/7365055

diff --git a/src/pkg/syscall/route_bsd.go b/src/pkg/syscall/route_bsd.go
index e17d976b1548723cd1b19cc42c9662c7ac988173..62c5ce1a31b5abffa1895d98ec7f8205b94409f9 100644 (file)
--- a/src/pkg/syscall/route_bsd.go
+++ b/src/pkg/syscall/route_bsd.go
@@ -8,9 +8,7 @@
 
 package syscall
 
-import (
-       "unsafe"
-)
+import "unsafe"
 
 // Round the length of a raw sockaddr up to align it properly.
 func rsaAlignOf(salen int) int {
@@ -31,7 +29,6 @@ func rsaAlignOf(salen int) int {
 // parameters.
 func RouteRIB(facility, param int) ([]byte, error) {
        mib := []_C_int{CTL_NET, AF_ROUTE, 0, 0, _C_int(facility), _C_int(param)}
-
        // Find size.
        n := uintptr(0)
        if err := sysctl(mib, nil, &n, nil, 0); err != nil {
@@ -40,12 +37,10 @@ func RouteRIB(facility, param int) ([]byte, error) {
        if n == 0 {
                return nil, nil
        }
-
        tab := make([]byte, n)
        if err := sysctl(mib, &tab[0], &n, nil, 0); err != nil {
                return nil, err
        }
-
        return tab[:n], nil
 }
 
@@ -76,13 +71,12 @@ func (m *RouteMessage) sockaddr() []Sockaddr {
                af  int
                sas [4]Sockaddr
        )
-
-       buf := m.Data[:]
+       b := m.Data[:]
        for i := uint(0); i < RTAX_MAX; i++ {
                if m.Header.Addrs&rtaRtMask&(1<<i) == 0 {
                        continue
                }
-               rsa := (*RawSockaddr)(unsafe.Pointer(&buf[0]))
+               rsa := (*RawSockaddr)(unsafe.Pointer(&b[0]))
                switch i {
                case RTAX_DST, RTAX_GATEWAY:
                        sa, err := anyToSockaddr((*RawSockaddrAny)(unsafe.Pointer(rsa)))
@@ -96,14 +90,14 @@ func (m *RouteMessage) sockaddr() []Sockaddr {
                case RTAX_NETMASK, RTAX_GENMASK:
                        switch af {
                        case AF_INET:
-                               rsa4 := (*RawSockaddrInet4)(unsafe.Pointer(&buf[0]))
+                               rsa4 := (*RawSockaddrInet4)(unsafe.Pointer(&b[0]))
                                sa := new(SockaddrInet4)
                                for j := 0; rsa4.Len > 0 && j < int(rsa4.Len)-int(unsafe.Offsetof(rsa4.Addr)); j++ {
                                        sa.Addr[j] = rsa4.Addr[j]
                                }
                                sas[i] = sa
                        case AF_INET6:
-                               rsa6 := (*RawSockaddrInet6)(unsafe.Pointer(&buf[0]))
+                               rsa6 := (*RawSockaddrInet6)(unsafe.Pointer(&b[0]))
                                sa := new(SockaddrInet6)
                                for j := 0; rsa6.Len > 0 && j < int(rsa6.Len)-int(unsafe.Offsetof(rsa6.Addr)); j++ {
                                        sa.Addr[j] = rsa6.Addr[j]
@@ -111,9 +105,8 @@ func (m *RouteMessage) sockaddr() []Sockaddr {
                                sas[i] = sa
                        }
                }
-               buf = buf[rsaAlignOf(int(rsa.Len)):]
+               b = b[rsaAlignOf(int(rsa.Len)):]
        }
-
        return sas[:]
 }
 
@@ -148,13 +141,12 @@ func (m *InterfaceAddrMessage) sockaddr() (sas []Sockaddr) {
        if m.Header.Addrs&rtaIfaMask == 0 {
                return nil
        }
-
-       buf := m.Data[:]
+       b := m.Data[:]
        for i := uint(0); i < RTAX_MAX; i++ {
                if m.Header.Addrs&rtaIfaMask&(1<<i) == 0 {
                        continue
                }
-               rsa := (*RawSockaddr)(unsafe.Pointer(&buf[0]))
+               rsa := (*RawSockaddr)(unsafe.Pointer(&b[0]))
                switch i {
                case RTAX_IFA:
                        sa, err := anyToSockaddr((*RawSockaddrAny)(unsafe.Pointer(rsa)))
@@ -174,22 +166,21 @@ func (m *InterfaceAddrMessage) sockaddr() (sas []Sockaddr) {
                case RTAX_BRD:
                        // nothing to do
                }
-               buf = buf[rsaAlignOf(int(rsa.Len)):]
+               b = b[rsaAlignOf(int(rsa.Len)):]
        }
-
        return sas
 }
 
-// ParseRoutingMessage parses buf as routing messages and returns
-// the slice containing the RoutingMessage interfaces.
-func ParseRoutingMessage(buf []byte) (msgs []RoutingMessage, err error) {
-       for len(buf) >= anyMessageLen {
-               any := (*anyMessage)(unsafe.Pointer(&buf[0]))
+// ParseRoutingMessage parses b as routing messages and returns the
+// slice containing the RoutingMessage interfaces.
+func ParseRoutingMessage(b []byte) (msgs []RoutingMessage, err error) {
+       for len(b) >= anyMessageLen {
+               any := (*anyMessage)(unsafe.Pointer(&b[0]))
                if any.Version != RTM_VERSION {
                        return nil, EINVAL
                }
-               msgs = append(msgs, any.toRoutingMessage(buf))
-               buf = buf[any.Msglen:]
+               msgs = append(msgs, any.toRoutingMessage(b))
+               b = b[any.Msglen:]
        }
        return msgs, nil
 }

diff --git a/src/pkg/syscall/route_darwin.go b/src/pkg/syscall/route_darwin.go
index 410e70a138a9ffaed192a94f2ea53da2f1af6c5a..ad2790723053a9dbd6f3cba7cb4813892892a0c9 100644 (file)
--- a/src/pkg/syscall/route_darwin.go
+++ b/src/pkg/syscall/route_darwin.go
@@ -6,36 +6,22 @@
 
 package syscall
 
-import (
-       "unsafe"
-)
+import "unsafe"
 
-func (any *anyMessage) toRoutingMessage(buf []byte) RoutingMessage {
+func (any *anyMessage) toRoutingMessage(b []byte) RoutingMessage {
        switch any.Type {
        case RTM_ADD, RTM_DELETE, RTM_CHANGE, RTM_GET, RTM_LOSING, RTM_REDIRECT, RTM_MISS, RTM_LOCK, RTM_RESOLVE:
                p := (*RouteMessage)(unsafe.Pointer(any))
-               rtm := &RouteMessage{}
-               rtm.Header = p.Header
-               rtm.Data = buf[SizeofRtMsghdr:any.Msglen]
-               return rtm
+               return &RouteMessage{Header: p.Header, Data: b[SizeofRtMsghdr:any.Msglen]}
        case RTM_IFINFO:
                p := (*InterfaceMessage)(unsafe.Pointer(any))
-               ifm := &InterfaceMessage{}
-               ifm.Header = p.Header
-               ifm.Data = buf[SizeofIfMsghdr:any.Msglen]
-               return ifm
+               return &InterfaceMessage{Header: p.Header, Data: b[SizeofIfMsghdr:any.Msglen]}
        case RTM_NEWADDR, RTM_DELADDR:
                p := (*InterfaceAddrMessage)(unsafe.Pointer(any))
-               ifam := &InterfaceAddrMessage{}
-               ifam.Header = p.Header
-               ifam.Data = buf[SizeofIfaMsghdr:any.Msglen]
-               return ifam
+               return &InterfaceAddrMessage{Header: p.Header, Data: b[SizeofIfaMsghdr:any.Msglen]}
        case RTM_NEWMADDR2, RTM_DELMADDR:
                p := (*InterfaceMulticastAddrMessage)(unsafe.Pointer(any))
-               ifmam := &InterfaceMulticastAddrMessage{}
-               ifmam.Header = p.Header
-               ifmam.Data = buf[SizeofIfmaMsghdr2:any.Msglen]
-               return ifmam
+               return &InterfaceMulticastAddrMessage{Header: p.Header, Data: b[SizeofIfmaMsghdr2:any.Msglen]}
        }
        return nil
 }
@@ -53,13 +39,12 @@ func (m *InterfaceMulticastAddrMessage) sockaddr() (sas []Sockaddr) {
        if m.Header.Addrs&rtaIfmaMask == 0 {
                return nil
        }
-
-       buf := m.Data[:]
+       b := m.Data[:]
        for i := uint(0); i < RTAX_MAX; i++ {
                if m.Header.Addrs&rtaIfmaMask&(1<<i) == 0 {
                        continue
                }
-               rsa := (*RawSockaddr)(unsafe.Pointer(&buf[0]))
+               rsa := (*RawSockaddr)(unsafe.Pointer(&b[0]))
                switch i {
                case RTAX_IFA:
                        sa, e := anyToSockaddr((*RawSockaddrAny)(unsafe.Pointer(rsa)))
@@ -70,8 +55,7 @@ func (m *InterfaceMulticastAddrMessage) sockaddr() (sas []Sockaddr) {
                case RTAX_GATEWAY, RTAX_IFP:
                        // nothing to do
                }
-               buf = buf[rsaAlignOf(int(rsa.Len)):]
+               b = b[rsaAlignOf(int(rsa.Len)):]
        }
-
        return sas
 }

diff --git a/src/pkg/syscall/route_freebsd.go b/src/pkg/syscall/route_freebsd.go
index 094e17044dbb1fe8069a3de917b797f354389711..d8f80316b8c2cfd2e49fd6f6e5fdbc90662deae3 100644 (file)
--- a/src/pkg/syscall/route_freebsd.go
+++ b/src/pkg/syscall/route_freebsd.go
@@ -6,40 +6,37 @@
 
 package syscall
 
-import (
-       "unsafe"
-)
+import "unsafe"
 
-func (any *anyMessage) toRoutingMessage(buf []byte) RoutingMessage {
+func (any *anyMessage) toRoutingMessage(b []byte) RoutingMessage {
        switch any.Type {
        case RTM_ADD, RTM_DELETE, RTM_CHANGE, RTM_GET, RTM_LOSING, RTM_REDIRECT, RTM_MISS, RTM_LOCK, RTM_RESOLVE:
                p := (*RouteMessage)(unsafe.Pointer(any))
-               rtm := &RouteMessage{}
-               rtm.Header = p.Header
-               rtm.Data = buf[SizeofRtMsghdr:any.Msglen]
-               return rtm
+               return &RouteMessage{Header: p.Header, Data: b[SizeofRtMsghdr:any.Msglen]}
        case RTM_IFINFO:
                p := (*InterfaceMessage)(unsafe.Pointer(any))
-               ifm := &InterfaceMessage{}
-               ifm.Header = p.Header
-               ifm.Data = buf[SizeofIfMsghdr:any.Msglen]
-               return ifm
+               return &InterfaceMessage{Header: p.Header, Data: b[SizeofIfMsghdr:any.Msglen]}
+       case RTM_IFANNOUNCE:
+               p := (*InterfaceAnnounceMessage)(unsafe.Pointer(any))
+               return &InterfaceAnnounceMessage{Header: p.Header}
        case RTM_NEWADDR, RTM_DELADDR:
                p := (*InterfaceAddrMessage)(unsafe.Pointer(any))
-               ifam := &InterfaceAddrMessage{}
-               ifam.Header = p.Header
-               ifam.Data = buf[SizeofIfaMsghdr:any.Msglen]
-               return ifam
+               return &InterfaceAddrMessage{Header: p.Header, Data: b[SizeofIfaMsghdr:any.Msglen]}
        case RTM_NEWMADDR, RTM_DELMADDR:
                p := (*InterfaceMulticastAddrMessage)(unsafe.Pointer(any))
-               ifmam := &InterfaceMulticastAddrMessage{}
-               ifmam.Header = p.Header
-               ifmam.Data = buf[SizeofIfmaMsghdr:any.Msglen]
-               return ifmam
+               return &InterfaceMulticastAddrMessage{Header: p.Header, Data: b[SizeofIfmaMsghdr:any.Msglen]}
        }
        return nil
 }
 
+// InterfaceAnnounceMessage represents a routing message containing
+// network interface arrival and depature information.
+type InterfaceAnnounceMessage struct {
+       Header IfAnnounceMsghdr
+}
+
+func (m *InterfaceAnnounceMessage) sockaddr() (sas []Sockaddr) { return nil }
+
 // InterfaceMulticastAddrMessage represents a routing message
 // containing network interface address entries.
 type InterfaceMulticastAddrMessage struct {
@@ -53,13 +50,12 @@ func (m *InterfaceMulticastAddrMessage) sockaddr() (sas []Sockaddr) {
        if m.Header.Addrs&rtaIfmaMask == 0 {
                return nil
        }
-
-       buf := m.Data[:]
+       b := m.Data[:]
        for i := uint(0); i < RTAX_MAX; i++ {
                if m.Header.Addrs&rtaIfmaMask&(1<<i) == 0 {
                        continue
                }
-               rsa := (*RawSockaddr)(unsafe.Pointer(&buf[0]))
+               rsa := (*RawSockaddr)(unsafe.Pointer(&b[0]))
                switch i {
                case RTAX_IFA:
                        sa, e := anyToSockaddr((*RawSockaddrAny)(unsafe.Pointer(rsa)))
@@ -70,8 +66,7 @@ func (m *InterfaceMulticastAddrMessage) sockaddr() (sas []Sockaddr) {
                case RTAX_GATEWAY, RTAX_IFP:
                        // nothing to do
                }
-               buf = buf[rsaAlignOf(int(rsa.Len)):]
+               b = b[rsaAlignOf(int(rsa.Len)):]
        }
-
        return sas
 }

diff --git a/src/pkg/syscall/route_netbsd.go b/src/pkg/syscall/route_netbsd.go
index d6d9031bcbf06cc033756bd1110946840b7903c5..a6baa02f80256de6c13439b8b00fe7d8793686aa 100644 (file)
--- a/src/pkg/syscall/route_netbsd.go
+++ b/src/pkg/syscall/route_netbsd.go
@@ -6,30 +6,30 @@
 
 package syscall
 
-import (
-       "unsafe"
-)
+import "unsafe"
 
-func (any *anyMessage) toRoutingMessage(buf []byte) RoutingMessage {
+func (any *anyMessage) toRoutingMessage(b []byte) RoutingMessage {
        switch any.Type {
        case RTM_ADD, RTM_DELETE, RTM_CHANGE, RTM_GET, RTM_LOSING, RTM_REDIRECT, RTM_MISS, RTM_LOCK, RTM_RESOLVE:
                p := (*RouteMessage)(unsafe.Pointer(any))
-               rtm := &RouteMessage{}
-               rtm.Header = p.Header
-               rtm.Data = buf[SizeofRtMsghdr:any.Msglen]
-               return rtm
+               return &RouteMessage{Header: p.Header, Data: b[SizeofRtMsghdr:any.Msglen]}
        case RTM_IFINFO:
                p := (*InterfaceMessage)(unsafe.Pointer(any))
-               ifm := &InterfaceMessage{}
-               ifm.Header = p.Header
-               ifm.Data = buf[SizeofIfMsghdr:any.Msglen]
-               return ifm
+               return &InterfaceMessage{Header: p.Header, Data: b[SizeofIfMsghdr:any.Msglen]}
+       case RTM_IFANNOUNCE:
+               p := (*InterfaceAnnounceMessage)(unsafe.Pointer(any))
+               return &InterfaceAnnounceMessage{Header: p.Header}
        case RTM_NEWADDR, RTM_DELADDR:
                p := (*InterfaceAddrMessage)(unsafe.Pointer(any))
-               ifam := &InterfaceAddrMessage{}
-               ifam.Header = p.Header
-               ifam.Data = buf[SizeofIfaMsghdr:any.Msglen]
-               return ifam
+               return &InterfaceAddrMessage{Header: p.Header, Data: b[SizeofIfaMsghdr:any.Msglen]}
        }
        return nil
 }
+
+// InterfaceAnnounceMessage represents a routing message containing
+// network interface arrival and depature information.
+type InterfaceAnnounceMessage struct {
+       Header IfAnnounceMsghdr
+}
+
+func (m *InterfaceAnnounceMessage) sockaddr() (sas []Sockaddr) { return nil }

diff --git a/src/pkg/syscall/route_openbsd.go b/src/pkg/syscall/route_openbsd.go
index 30e1cac46fcda6f36a59102e81d5846a4114071d..223c15779168b652931f56bd99d4c8be71ff9c26 100644 (file)
--- a/src/pkg/syscall/route_openbsd.go
+++ b/src/pkg/syscall/route_openbsd.go
@@ -6,30 +6,30 @@
 
 package syscall
 
-import (
-       "unsafe"
-)
+import "unsafe"
 
-func (any *anyMessage) toRoutingMessage(buf []byte) RoutingMessage {
+func (any *anyMessage) toRoutingMessage(b []byte) RoutingMessage {
        switch any.Type {
        case RTM_ADD, RTM_DELETE, RTM_CHANGE, RTM_GET, RTM_LOSING, RTM_REDIRECT, RTM_MISS, RTM_LOCK, RTM_RESOLVE:
                p := (*RouteMessage)(unsafe.Pointer(any))
-               rtm := &RouteMessage{}
-               rtm.Header = p.Header
-               rtm.Data = buf[SizeofRtMsghdr:any.Msglen]
-               return rtm
+               return &RouteMessage{Header: p.Header, Data: b[SizeofRtMsghdr:any.Msglen]}
        case RTM_IFINFO:
                p := (*InterfaceMessage)(unsafe.Pointer(any))
-               ifm := &InterfaceMessage{}
-               ifm.Header = p.Header
-               ifm.Data = buf[SizeofIfMsghdr:any.Msglen]
-               return ifm
+               return &InterfaceMessage{Header: p.Header, Data: b[SizeofIfMsghdr:any.Msglen]}
+       case RTM_IFANNOUNCE:
+               p := (*InterfaceAnnounceMessage)(unsafe.Pointer(any))
+               return &InterfaceAnnounceMessage{Header: p.Header}
        case RTM_NEWADDR, RTM_DELADDR:
                p := (*InterfaceAddrMessage)(unsafe.Pointer(any))
-               ifam := &InterfaceAddrMessage{}
-               ifam.Header = p.Header
-               ifam.Data = buf[SizeofIfaMsghdr:any.Msglen]
-               return ifam
+               return &InterfaceAddrMessage{Header: p.Header, Data: b[SizeofIfaMsghdr:any.Msglen]}
        }
        return nil
 }
+
+// InterfaceAnnounceMessage represents a routing message containing
+// network interface arrival and depature information.
+type InterfaceAnnounceMessage struct {
+       Header IfAnnounceMsghdr
+}
+
+func (m *InterfaceAnnounceMessage) sockaddr() (sas []Sockaddr) { return nil }