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..8e47ff8
--- /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.
+
+//go: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
+}