1 files changed, 262 insertions, 0 deletions
diff --git a/src/pkg/net/interface_linux.go b/src/pkg/net/interface_linux.go
new file mode 100644
index 000000000..3d2a0bb9f
--- /dev/null
+++ b/src/pkg/net/interface_linux.go
@@ -0,0 +1,262 @@
+// 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.
+
+// Network interface identification for Linux
+
+package net
+
+import (
+	"fmt"
+	"os"
+	"syscall"
+	"unsafe"
+)
+
+// If the ifindex is zero, interfaceTable returns mappings of all
+// network interfaces.  Otheriwse it returns a mapping of a specific
+// interface.
+func interfaceTable(ifindex int) ([]Interface, os.Error) {
+	var (
+		ift  []Interface
+		tab  []byte
+		msgs []syscall.NetlinkMessage
+		e    int
+	)
+
+	tab, e = syscall.NetlinkRIB(syscall.RTM_GETLINK, syscall.AF_UNSPEC)
+	if e != 0 {
+		return nil, os.NewSyscallError("netlink rib", e)
+	}
+
+	msgs, e = syscall.ParseNetlinkMessage(tab)
+	if e != 0 {
+		return nil, os.NewSyscallError("netlink message", e)
+	}
+
+	for _, m := range msgs {
+		switch m.Header.Type {
+		case syscall.NLMSG_DONE:
+			goto done
+		case syscall.RTM_NEWLINK:
+			ifim := (*syscall.IfInfomsg)(unsafe.Pointer(&m.Data[0]))
+			if ifindex == 0 || ifindex == int(ifim.Index) {
+				attrs, e := syscall.ParseNetlinkRouteAttr(&m)
+				if e != 0 {
+					return nil, os.NewSyscallError("netlink routeattr", e)
+				}
+				ifi := newLink(attrs, ifim)
+				ift = append(ift, ifi)
+			}
+		}
+	}
+
+done:
+	return ift, nil
+}
+
+func newLink(attrs []syscall.NetlinkRouteAttr, ifim *syscall.IfInfomsg) Interface {
+	ifi := Interface{Index: int(ifim.Index), Flags: linkFlags(ifim.Flags)}
+	for _, a := range attrs {
+		switch a.Attr.Type {
+		case syscall.IFLA_ADDRESS:
+			var nonzero bool
+			for _, b := range a.Value {
+				if b != 0 {
+					nonzero = true
+				}
+			}
+			if nonzero {
+				ifi.HardwareAddr = a.Value[:]
+			}
+		case syscall.IFLA_IFNAME:
+			ifi.Name = string(a.Value[:len(a.Value)-1])
+		case syscall.IFLA_MTU:
+			ifi.MTU = int(uint32(a.Value[3])<<24 | uint32(a.Value[2])<<16 | uint32(a.Value[1])<<8 | uint32(a.Value[0]))
+		}
+	}
+	return ifi
+}
+
+func linkFlags(rawFlags uint32) Flags {
+	var f Flags
+	if rawFlags&syscall.IFF_UP != 0 {
+		f |= FlagUp
+	}
+	if rawFlags&syscall.IFF_BROADCAST != 0 {
+		f |= FlagBroadcast
+	}
+	if rawFlags&syscall.IFF_LOOPBACK != 0 {
+		f |= FlagLoopback
+	}
+	if rawFlags&syscall.IFF_POINTOPOINT != 0 {
+		f |= FlagPointToPoint
+	}
+	if rawFlags&syscall.IFF_MULTICAST != 0 {
+		f |= FlagMulticast
+	}
+	return f
+}
+
+// If the ifindex is zero, interfaceAddrTable returns addresses
+// for all network interfaces.  Otherwise it returns addresses
+// for a specific interface.
+func interfaceAddrTable(ifindex int) ([]Addr, os.Error) {
+	var (
+		tab   []byte
+		e     int
+		err   os.Error
+		ifat4 []Addr
+		ifat6 []Addr
+		msgs4 []syscall.NetlinkMessage
+		msgs6 []syscall.NetlinkMessage
+	)
+
+	tab, e = syscall.NetlinkRIB(syscall.RTM_GETADDR, syscall.AF_INET)
+	if e != 0 {
+		return nil, os.NewSyscallError("netlink rib", e)
+	}
+	msgs4, e = syscall.ParseNetlinkMessage(tab)
+	if e != 0 {
+		return nil, os.NewSyscallError("netlink message", e)
+	}
+	ifat4, err = addrTable(msgs4, ifindex)
+	if err != nil {
+		return nil, err
+	}
+
+	tab, e = syscall.NetlinkRIB(syscall.RTM_GETADDR, syscall.AF_INET6)
+	if e != 0 {
+		return nil, os.NewSyscallError("netlink rib", e)
+	}
+	msgs6, e = syscall.ParseNetlinkMessage(tab)
+	if e != 0 {
+		return nil, os.NewSyscallError("netlink message", e)
+	}
+	ifat6, err = addrTable(msgs6, ifindex)
+	if err != nil {
+		return nil, err
+	}
+
+	return append(ifat4, ifat6...), nil
+}
+
+func addrTable(msgs []syscall.NetlinkMessage, ifindex int) ([]Addr, os.Error) {
+	var ifat []Addr
+
+	for _, m := range msgs {
+		switch m.Header.Type {
+		case syscall.NLMSG_DONE:
+			goto done
+		case syscall.RTM_NEWADDR:
+			ifam := (*syscall.IfAddrmsg)(unsafe.Pointer(&m.Data[0]))
+			if ifindex == 0 || ifindex == int(ifam.Index) {
+				attrs, e := syscall.ParseNetlinkRouteAttr(&m)
+				if e != 0 {
+					return nil, os.NewSyscallError("netlink routeattr", e)
+				}
+				ifat = append(ifat, newAddr(attrs, int(ifam.Family))...)
+			}
+		}
+	}
+
+done:
+	return ifat, nil
+}
+
+func newAddr(attrs []syscall.NetlinkRouteAttr, family int) []Addr {
+	var ifat []Addr
+
+	for _, a := range attrs {
+		switch a.Attr.Type {
+		case syscall.IFA_ADDRESS:
+			switch family {
+			case syscall.AF_INET:
+				ifa := &IPAddr{IP: IPv4(a.Value[0], a.Value[1], a.Value[2], a.Value[3])}
+				ifat = append(ifat, ifa.toAddr())
+			case syscall.AF_INET6:
+				ifa := &IPAddr{IP: make(IP, IPv6len)}
+				copy(ifa.IP, a.Value[:])
+				ifat = append(ifat, ifa.toAddr())
+			}
+		}
+	}
+
+	return ifat
+}
+
+// If the ifindex is zero, interfaceMulticastAddrTable returns
+// addresses for all network interfaces.  Otherwise it returns
+// addresses for a specific interface.
+func interfaceMulticastAddrTable(ifindex int) ([]Addr, os.Error) {
+	var (
+		ifi *Interface
+		err os.Error
+	)
+
+	if ifindex > 0 {
+		ifi, err = InterfaceByIndex(ifindex)
+		if err != nil {
+			return nil, err
+		}
+	}
+
+	ifmat4 := parseProcNetIGMP(ifi)
+	ifmat6 := parseProcNetIGMP6(ifi)
+
+	return append(ifmat4, ifmat6...), nil
+}
+
+func parseProcNetIGMP(ifi *Interface) []Addr {
+	var (
+		ifmat []Addr
+		name  string
+	)
+
+	fd, err := open("/proc/net/igmp")
+	if err != nil {
+		return nil
+	}
+	defer fd.close()
+
+	fd.readLine() // skip first line
+	b := make([]byte, IPv4len)
+	for l, ok := fd.readLine(); ok; l, ok = fd.readLine() {
+		f := getFields(l)
+		switch len(f) {
+		case 4:
+			if ifi == nil || name == ifi.Name {
+				fmt.Sscanf(f[0], "%08x", &b)
+				ifma := IPAddr{IP: IPv4(b[3], b[2], b[1], b[0])}
+				ifmat = append(ifmat, ifma.toAddr())
+			}
+		case 5:
+			name = f[1]
+		}
+	}
+
+	return ifmat
+}
+
+func parseProcNetIGMP6(ifi *Interface) []Addr {
+	var ifmat []Addr
+
+	fd, err := open("/proc/net/igmp6")
+	if err != nil {
+		return nil
+	}
+	defer fd.close()
+
+	b := make([]byte, IPv6len)
+	for l, ok := fd.readLine(); ok; l, ok = fd.readLine() {
+		f := getFields(l)
+		if ifi == nil || f[1] == ifi.Name {
+			fmt.Sscanf(f[2], "%32x", &b)
+			ifma := IPAddr{IP: IP{b[0], b[1], b[2], b[3], b[4], b[5], b[6], b[7], b[8], b[9], b[10], b[11], b[12], b[13], b[14], b[15]}}
+			ifmat = append(ifmat, ifma.toAddr())
+
+		}
+	}
+
+	return ifmat
+}