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-rw-r--r--src/syscall/route_bsd.go364
1 files changed, 364 insertions, 0 deletions
diff --git a/src/syscall/route_bsd.go b/src/syscall/route_bsd.go
new file mode 100644
index 0000000..b364eea
--- /dev/null
+++ b/src/syscall/route_bsd.go
@@ -0,0 +1,364 @@
+// Copyright 2011 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 netbsd openbsd
+
+package syscall
+
+import (
+ "runtime"
+ "unsafe"
+)
+
+var (
+ freebsdConfArch string // "machine $arch" line in kern.conftxt on freebsd
+ minRoutingSockaddrLen = rsaAlignOf(0)
+)
+
+// Round the length of a raw sockaddr up to align it properly.
+func rsaAlignOf(salen int) int {
+ salign := sizeofPtr
+ if darwin64Bit {
+ // Darwin kernels require 32-bit aligned access to
+ // routing facilities.
+ salign = 4
+ } else if netbsd32Bit {
+ // NetBSD 6 and beyond kernels require 64-bit aligned
+ // access to routing facilities.
+ salign = 8
+ } else if runtime.GOOS == "freebsd" {
+ // In the case of kern.supported_archs="amd64 i386",
+ // we need to know the underlying kernel's
+ // architecture because the alignment for routing
+ // facilities are set at the build time of the kernel.
+ if freebsdConfArch == "amd64" {
+ salign = 8
+ }
+ }
+ if salen == 0 {
+ return salign
+ }
+ return (salen + salign - 1) & ^(salign - 1)
+}
+
+// parseSockaddrLink parses b as a datalink socket address.
+func parseSockaddrLink(b []byte) (*SockaddrDatalink, error) {
+ if len(b) < 8 {
+ return nil, EINVAL
+ }
+ sa, _, err := parseLinkLayerAddr(b[4:])
+ if err != nil {
+ return nil, err
+ }
+ rsa := (*RawSockaddrDatalink)(unsafe.Pointer(&b[0]))
+ sa.Len = rsa.Len
+ sa.Family = rsa.Family
+ sa.Index = rsa.Index
+ return sa, nil
+}
+
+// parseLinkLayerAddr parses b as a datalink socket address in
+// conventional BSD kernel form.
+func parseLinkLayerAddr(b []byte) (*SockaddrDatalink, int, error) {
+ // The encoding looks like the following:
+ // +----------------------------+
+ // | Type (1 octet) |
+ // +----------------------------+
+ // | Name length (1 octet) |
+ // +----------------------------+
+ // | Address length (1 octet) |
+ // +----------------------------+
+ // | Selector length (1 octet) |
+ // +----------------------------+
+ // | Data (variable) |
+ // +----------------------------+
+ type linkLayerAddr struct {
+ Type byte
+ Nlen byte
+ Alen byte
+ Slen byte
+ }
+ lla := (*linkLayerAddr)(unsafe.Pointer(&b[0]))
+ l := 4 + int(lla.Nlen) + int(lla.Alen) + int(lla.Slen)
+ if len(b) < l {
+ return nil, 0, EINVAL
+ }
+ b = b[4:]
+ sa := &SockaddrDatalink{Type: lla.Type, Nlen: lla.Nlen, Alen: lla.Alen, Slen: lla.Slen}
+ for i := 0; len(sa.Data) > i && i < l-4; i++ {
+ sa.Data[i] = int8(b[i])
+ }
+ return sa, rsaAlignOf(l), nil
+}
+
+// parseSockaddrInet parses b as an internet socket address.
+func parseSockaddrInet(b []byte, family byte) (Sockaddr, error) {
+ switch family {
+ case AF_INET:
+ if len(b) < SizeofSockaddrInet4 {
+ return nil, EINVAL
+ }
+ rsa := (*RawSockaddrAny)(unsafe.Pointer(&b[0]))
+ return anyToSockaddr(rsa)
+ case AF_INET6:
+ if len(b) < SizeofSockaddrInet6 {
+ return nil, EINVAL
+ }
+ rsa := (*RawSockaddrAny)(unsafe.Pointer(&b[0]))
+ return anyToSockaddr(rsa)
+ default:
+ return nil, EINVAL
+ }
+}
+
+const (
+ offsetofInet4 = int(unsafe.Offsetof(RawSockaddrInet4{}.Addr))
+ offsetofInet6 = int(unsafe.Offsetof(RawSockaddrInet6{}.Addr))
+)
+
+// parseNetworkLayerAddr parses b as an internet socket address in
+// conventional BSD kernel form.
+func parseNetworkLayerAddr(b []byte, family byte) (Sockaddr, error) {
+ // The encoding looks similar to the NLRI encoding.
+ // +----------------------------+
+ // | Length (1 octet) |
+ // +----------------------------+
+ // | Address prefix (variable) |
+ // +----------------------------+
+ //
+ // The differences between the kernel form and the NLRI
+ // encoding are:
+ //
+ // - The length field of the kernel form indicates the prefix
+ // length in bytes, not in bits
+ //
+ // - In the kernel form, zero value of the length field
+ // doesn't mean 0.0.0.0/0 or ::/0
+ //
+ // - The kernel form appends leading bytes to the prefix field
+ // to make the <length, prefix> tuple to be conformed with
+ // the routing message boundary
+ l := int(rsaAlignOf(int(b[0])))
+ if len(b) < l {
+ return nil, EINVAL
+ }
+ // Don't reorder case expressions.
+ // The case expressions for IPv6 must come first.
+ switch {
+ case b[0] == SizeofSockaddrInet6:
+ sa := &SockaddrInet6{}
+ copy(sa.Addr[:], b[offsetofInet6:])
+ return sa, nil
+ case family == AF_INET6:
+ sa := &SockaddrInet6{}
+ if l-1 < offsetofInet6 {
+ copy(sa.Addr[:], b[1:l])
+ } else {
+ copy(sa.Addr[:], b[l-offsetofInet6:l])
+ }
+ return sa, nil
+ case b[0] == SizeofSockaddrInet4:
+ sa := &SockaddrInet4{}
+ copy(sa.Addr[:], b[offsetofInet4:])
+ return sa, nil
+ default: // an old fashion, AF_UNSPEC or unknown means AF_INET
+ sa := &SockaddrInet4{}
+ if l-1 < offsetofInet4 {
+ copy(sa.Addr[:], b[1:l])
+ } else {
+ copy(sa.Addr[:], b[l-offsetofInet4:l])
+ }
+ return sa, nil
+ }
+}
+
+// RouteRIB returns routing information base, as known as RIB,
+// which consists of network facility information, states and
+// parameters.
+//
+// Deprecated: Use golang.org/x/net/route instead.
+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 {
+ return nil, err
+ }
+ 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
+}
+
+// RoutingMessage represents a routing message.
+//
+// Deprecated: Use golang.org/x/net/route instead.
+type RoutingMessage interface {
+ sockaddr() ([]Sockaddr, error)
+}
+
+const anyMessageLen = int(unsafe.Sizeof(anyMessage{}))
+
+type anyMessage struct {
+ Msglen uint16
+ Version uint8
+ Type uint8
+}
+
+// RouteMessage represents a routing message containing routing
+// entries.
+//
+// Deprecated: Use golang.org/x/net/route instead.
+type RouteMessage struct {
+ Header RtMsghdr
+ Data []byte
+}
+
+func (m *RouteMessage) sockaddr() ([]Sockaddr, error) {
+ var sas [RTAX_MAX]Sockaddr
+ b := m.Data[:]
+ family := uint8(AF_UNSPEC)
+ for i := uint(0); i < RTAX_MAX && len(b) >= minRoutingSockaddrLen; i++ {
+ if m.Header.Addrs&(1<<i) == 0 {
+ continue
+ }
+ rsa := (*RawSockaddr)(unsafe.Pointer(&b[0]))
+ switch rsa.Family {
+ case AF_LINK:
+ sa, err := parseSockaddrLink(b)
+ if err != nil {
+ return nil, err
+ }
+ sas[i] = sa
+ b = b[rsaAlignOf(int(rsa.Len)):]
+ case AF_INET, AF_INET6:
+ sa, err := parseSockaddrInet(b, rsa.Family)
+ if err != nil {
+ return nil, err
+ }
+ sas[i] = sa
+ b = b[rsaAlignOf(int(rsa.Len)):]
+ family = rsa.Family
+ default:
+ sa, err := parseNetworkLayerAddr(b, family)
+ if err != nil {
+ return nil, err
+ }
+ sas[i] = sa
+ b = b[rsaAlignOf(int(b[0])):]
+ }
+ }
+ return sas[:], nil
+}
+
+// InterfaceMessage represents a routing message containing
+// network interface entries.
+//
+// Deprecated: Use golang.org/x/net/route instead.
+type InterfaceMessage struct {
+ Header IfMsghdr
+ Data []byte
+}
+
+func (m *InterfaceMessage) sockaddr() ([]Sockaddr, error) {
+ var sas [RTAX_MAX]Sockaddr
+ if m.Header.Addrs&RTA_IFP == 0 {
+ return nil, nil
+ }
+ sa, err := parseSockaddrLink(m.Data[:])
+ if err != nil {
+ return nil, err
+ }
+ sas[RTAX_IFP] = sa
+ return sas[:], nil
+}
+
+// InterfaceAddrMessage represents a routing message containing
+// network interface address entries.
+//
+// Deprecated: Use golang.org/x/net/route instead.
+type InterfaceAddrMessage struct {
+ Header IfaMsghdr
+ Data []byte
+}
+
+func (m *InterfaceAddrMessage) sockaddr() ([]Sockaddr, error) {
+ var sas [RTAX_MAX]Sockaddr
+ b := m.Data[:]
+ family := uint8(AF_UNSPEC)
+ for i := uint(0); i < RTAX_MAX && len(b) >= minRoutingSockaddrLen; i++ {
+ if m.Header.Addrs&(1<<i) == 0 {
+ continue
+ }
+ rsa := (*RawSockaddr)(unsafe.Pointer(&b[0]))
+ switch rsa.Family {
+ case AF_LINK:
+ sa, err := parseSockaddrLink(b)
+ if err != nil {
+ return nil, err
+ }
+ sas[i] = sa
+ b = b[rsaAlignOf(int(rsa.Len)):]
+ case AF_INET, AF_INET6:
+ sa, err := parseSockaddrInet(b, rsa.Family)
+ if err != nil {
+ return nil, err
+ }
+ sas[i] = sa
+ b = b[rsaAlignOf(int(rsa.Len)):]
+ family = rsa.Family
+ default:
+ sa, err := parseNetworkLayerAddr(b, family)
+ if err != nil {
+ return nil, err
+ }
+ sas[i] = sa
+ b = b[rsaAlignOf(int(b[0])):]
+ }
+ }
+ return sas[:], nil
+}
+
+// ParseRoutingMessage parses b as routing messages and returns the
+// slice containing the RoutingMessage interfaces.
+//
+// Deprecated: Use golang.org/x/net/route instead.
+func ParseRoutingMessage(b []byte) (msgs []RoutingMessage, err error) {
+ nmsgs, nskips := 0, 0
+ for len(b) >= anyMessageLen {
+ nmsgs++
+ any := (*anyMessage)(unsafe.Pointer(&b[0]))
+ if any.Version != RTM_VERSION {
+ b = b[any.Msglen:]
+ continue
+ }
+ if m := any.toRoutingMessage(b); m == nil {
+ nskips++
+ } else {
+ msgs = append(msgs, m)
+ }
+ b = b[any.Msglen:]
+ }
+ // We failed to parse any of the messages - version mismatch?
+ if nmsgs != len(msgs)+nskips {
+ return nil, EINVAL
+ }
+ return msgs, nil
+}
+
+// ParseRoutingSockaddr parses msg's payload as raw sockaddrs and
+// returns the slice containing the Sockaddr interfaces.
+//
+// Deprecated: Use golang.org/x/net/route instead.
+func ParseRoutingSockaddr(msg RoutingMessage) ([]Sockaddr, error) {
+ sas, err := msg.sockaddr()
+ if err != nil {
+ return nil, err
+ }
+ return sas, nil
+}