Files
netlinkrb/lib/netlink/route/if_handler.rb
2011-05-03 13:50:01 +01:00

433 lines
14 KiB
Ruby

require 'netlink/message'
module Netlink
# struct rtnl_link_stats / rtnl_link_stats64
LinkStats = Struct.new :rx_packets, :tx_packets,
:rx_bytes, :tx_bytes,
:rx_errors, :tx_errors,
:rx_dropped, :tx_dropped,
:multicast, :collisions,
:rx_length_errors, :rx_over_errors,
:rx_crc_errors, :rx_frame_errors,
:rx_fifo_errors, :rx_missed_errors,
:tx_aborted_errorsr, :tx_carrier_errors,
:tx_fifo_errors, :tx_heartbeat_errors,
:tx_window_errors,
:rx_compressed, :tx_compressed
# struct ifmap
IFMap = Struct.new :mem_start, :mem_end, :base_addr, :irq, :dma, :port
# struct ifinfomsg
class IFInfo < RtattrMessage
code RTM_NEWLINK, RTM_DELLINK, RTM_GETLINK
field :family, :uchar
field :type, :ushort # ARPHRD_*
field :index, :int
field :flags, :uint # IFF_*
field :change, :uint, :default=>0xffffffff # flags to change
rtattr :address, IFLA_ADDRESS, :l2addr
rtattr :broadcast, IFLA_BROADCAST, :l2addr
rtattr :ifname, IFLA_IFNAME, :cstring
rtattr :mtu, IFLA_MTU, :uint32
rtattr :link, IFLA_LINK, :int32
rtattr :qdisc, IFLA_QDISC, :cstring
rtattr :stats32, IFLA_STATS,
:pack => lambda { |val,obj| val.to_a.pack("L23") },
:unpack => lambda { |str,obj| LinkStats.new(*(str.unpack("L23"))) }
rtattr :cost, IFLA_COST
rtattr :master, IFLA_MASTER, :uint32
rtattr :wireless, IFLA_WIRELESS
rtattr :protinfo, IFLA_PROTINFO, :uchar
rtattr :txqlen, IFLA_TXQLEN, :uint32
IFMAP_PACK = "QQQSCC".freeze #:nodoc:
rtattr :map, IFLA_MAP,
:pack => lambda { |val,obj| val.to_a.pack(IFMAP_PACK) },
:unpack => lambda { |str,obj| IFMap.new(*(str.unpack(IFMAP_PACK))) }
rtattr :weight, IFLA_WEIGHT, :uint32
rtattr :operstate, IFLA_OPERSTATE, :uchar
rtattr :linkmode, IFLA_LINKMODE, :uchar
rtattr :linkinfo, IFLA_LINKINFO # nested
rtattr :net_ns_pid, IFLA_NET_NS_PID, :uint32
rtattr :ifalias, IFLA_IFALIAS, :cstring
rtattr :num_vf, IFLA_NUM_VF, :uint32
rtattr :vfinfo_list, IFLA_VFINFO_LIST
rtattr :stats64, IFLA_STATS64,
:pack => lambda { |val,obj| val.to_a.pack("Q23") },
:unpack => lambda { |str,obj| LinkStats.new(*(str.unpack("Q23"))) }
rtattr :vf_ports, IFLA_VF_PORTS
rtattr :port_self, IFLA_PORT_SELF
# Return the best stats available (64bit or 32bit)
def stats
stats64 || stats32
end
# Link kind for special links, e.g. "vlan" or "gre"
def kind
linkinfo && linkinfo.kind
end
# Set link kind, creating a linkinfo member if necessary. e.g.
# i = IFAddr.new
# i.kind = "vlan"
# i.linkinfo.data = VlanInfo.new(...)
def kind=(str)
self.linkinfo ||= LinkInfo.new
linkinfo.kind = str
end
def kind?(str)
kind == str
end
def after_parse #:nodoc:
self.linkinfo = LinkInfo.parse(linkinfo) if linkinfo
end
end
class LinkInfo < RtattrMessage
rtattr :kind, IFLA_INFO_KIND, :cstring
rtattr :data, IFLA_INFO_DATA # rtattr packed, see below
rtattr :xstats, :IFLA_INFO_XSTATS # don't know
def after_parse #:nodoc:
case kind
when "vlan"
self.data = VlanInfo.parse(data)
end
end
end
class VlanFlags < CStruct
field :flags, :uint32
field :mask, :uint32, :default => 0xffffffff
end
# VLAN information is packed in rtattr format (there is no corresponding 'struct')
class VlanInfo < RtattrMessage
rtattr :id, IFLA_VLAN_ID, :ushort
rtattr :flags, IFLA_VLAN_FLAGS,
:unpack => lambda { |str,obj| VlanFlags.parse(str) }
rtattr :egress_qos, IFLA_VLAN_EGRESS_QOS
rtattr :ingress_qos, IFLA_VLAN_INGRESS_QOS
end
# struct ifa_cacheinfo
IFACacheInfo = Struct.new :prefered, :valid, :cstamp, :tstamp
# struct ifaddrmsg
class IFAddr < RtattrMessage
code RTM_NEWADDR, RTM_DELADDR, RTM_GETADDR
field :family, :uchar # Socket::AF_*
field :prefixlen, :uchar
field :flags, :uchar # IFA_F_*
field :scope, :uchar # RT_SCOPE_*
field :index, :int
rtattr :address, IFA_ADDRESS, :l3addr
rtattr :local, IFA_LOCAL, :l3addr
rtattr :label, IFA_LABEL, :cstring
rtattr :broadcast, IFA_BROADCAST, :l3addr
rtattr :anycast, IFA_ANYCAST, :l3addr
rtattr :cacheinfo, IFA_CACHEINFO,
:pack => lambda { |val,obj| val.to_a.pack("L*") },
:unpack => lambda { |str,obj| IFACacheInfo.new(*(str.unpack("L*"))) }
rtattr :multicast, IFA_MULTICAST, :l3addr
end
module Route
# This class provides an API for manipulating interfaces and addresses.
# Since we frequently need to map ifname to ifindex, or vice versa,
# we keep a memoized list of interfaces. If the interface list changes,
# you should create a new instance of this object.
class IFHandler
def initialize(nlsocket = Netlink::Route::Socket.new)
@nlsocket = nlsocket
clear_link_cache
clear_addr_cache
end
def clear_link_cache
@links = nil
@linkmap = nil
end
def clear_addr_cache
@addrs = nil
end
# Download a list of links (interfaces). Either returns an array of
# Netlink::IFInfo objects, or yields them to the supplied block.
#
# res = nl.read_links
# p res
# [#<Netlink::IFInfo {:family=>0, :type=>772, :index=>1,
# :flags=>65609, :change=>0, :ifname=>"lo", :txqlen=>0, :operstate=>0,
# :linkmode=>0, :mtu=>16436, :qdisc=>"noqueue", :map=>"...",
# :address=>"\x00\x00\x00\x00\x00\x00", :broadcast=>"\x00\x00\x00\x00\x00\x00",
# :stats32=>#<struct Netlink::LinkStats rx_packets=22, ...>,
# :stats64=>#<struct Netlink::LinkStats rx_packets=22, ...>}>, ...]
def read_links(opt=nil, &blk)
@nlsocket.send_request RTM_GETLINK, IFInfo.new(opt),
NLM_F_ROOT | NLM_F_MATCH | NLM_F_REQUEST
@nlsocket.receive_until_done(RTM_NEWLINK, &blk)
end
# Download a list of link addresses. Either returns an array of
# Netlink::IFAddr objects, or yields them to the supplied block.
# You will need to use the 'index' to cross reference to the interface.
#
# A hash of kernel options may be supplied, but likely only :family
# is honoured.
#
# res = nl.read_addrs(:family => Socket::AF_INET)
# p res
# [#<Netlink::IFAddr {:family=>2, :prefixlen=>8, :flags=>128, :scope=>254,
# :index=>1, :address=>#<IPAddr: IPv4:127.0.0.1/255.255.255.255>,
# :local=>#<IPAddr: IPv4:127.0.0.1/255.255.255.255>, :label=>"lo"}>, ...]
def read_addrs(opt=nil, &blk)
@nlsocket.send_request RTM_GETADDR, IFAddr.new(opt),
NLM_F_ROOT | NLM_F_MATCH | NLM_F_REQUEST
@nlsocket.receive_until_done(RTM_NEWADDR, &blk)
end
# Download a list of addresses, grouped as {index=>[addr,addr], index=>[addr,addr]}
def read_addrs_by_ifindex(opt=nil)
res = read_addrs(opt).group_by { |obj| obj.index }
res.default = EMPTY_ARRAY
res
end
# Iterate over all interfaces, or interfaces matching the given
# criteria. Returns an Enumerator if no block given.
#
# The full interface list is read once and memoized, so
# it is efficient to call this method multiple times.
#
# if.links { |x| p x }
# ethers = if.links(:type => Netlink::ARPHRD_ETHER).to_a
# vlans = if.links(:kind => "vlan").to_a
# if.links(:flags => Netlink::IFF_RUNNING)
# if.links(:noflags => Netlink::IFF_POINTOPOINT)
# if.links(:link => "lo") # vlan etc attached to this interface
def links(filter=nil, &blk)
return to_enum(:links, filter) unless block_given?
@links ||= read_links
return @links.each(&blk) unless filter
filter[:link] = index(filter[:link]) if filter.has_key?(:link)
@links.each do |l|
yield l if (!filter[:type] || l.type == filter[:type]) &&
(!filter[:kind] || l.kind?(filter[:kind])) &&
(!filter[:flags] || (l.flags & filter[:flags]) == filter[:flags]) &&
(!filter[:noflags] || (l.flags & filter[:noflags]) == 0) &&
(!filter[:link] || l.link == filter[:link])
end
end
# Return a memoized Hash of interfaces, keyed by both index and name
def linkmap
@linkmap ||= (
h = {}
links { |link| h[link.index] = h[link.ifname] = link }
h
)
end
# Return details of one interface, given its name or index.
# Raises exception if unknown value.
def [](key)
linkmap.fetch(key)
end
# Convert an interface index into name string, or nil if the
# index is nil or empty string. Raises exception for unknown values.
#
# nl = Netlink::Route::Socket.new
# nl.rt[Socket::AF_INET].each do |route|
# puts "iif=#{nl.if.name(route.iif)}"
# puts "oif=#{nl.if.name(route.oif)}"
# end
def name(index)
return nil if index.nil? || index == 0
self[index].ifname
end
# Convert an interface name into index. Returns 0 for nil or empty
# string. Otherwise raises an exception for unknown values.
def index(name)
case name
when Integer
name
when nil, EMPTY_STRING
0
else
self[name].index
end
end
# Add an interface (low-level)
#
# require 'netlink/route'
# rt = Netlink::Route::Socket.new
# rt.if.add_link(
# :link=>"lo",
# :linkinfo=>Netlink::LinkInfo.new(
# :kind=>"vlan",
# :data=>Netlink::VlanInfo.new(
# :id=>1234,
# :flags => Netlink::VlanFlags.new(
# :flags=>Netlink::VLAN_FLAG_LOOSE_BINDING,
# :mask=>0xffffffff
# ))))
def add_link(opt)
iplink_modify(RTM_NEWLINK, NLM_F_CREATE|NLM_F_EXCL, opt)
end
def change_link(opt)
iplink_modify(RTM_NEWLINK, NLM_F_REPLACE, opt)
end
def replace_link(opt)
iplink_modify(RTM_NEWLINK, NLM_F_CREATE|NLM_F_REPLACE, opt)
end
# Delete an existing link. Pass in ifname or index, or options
# hash {:index=>n}
def delete_link(opt)
case opt
when Integer
opt = {:index=>opt}
when String
opt = {:index=>index(opt)}
end
iplink_modify(RTM_DELLINK, 0, opt)
end
def iplink_modify(code, flags, msg) #:nodoc:
msg = IFInfo.new(msg)
if (flags & NLM_F_CREATE) != 0
raise "Missing :linkinfo" unless msg.linkinfo
raise "Missing :kind" unless msg.linkinfo.kind
else
raise "Missing :index" if msg.index.nil? || msg.index == 0
end
msg.index = index(msg.index) if msg.index.is_a?(String)
msg.link = index(msg.link) if msg.link.is_a?(String)
@nlsocket.cmd code, msg, flags|NLM_F_REQUEST
clear_link_cache
end
# Higher-level API to manipulate VLAN interface.
# rt.if.add_vlan(
# :link=>"lo",
# :vlan_id=>1234,
# :vlan_flags=>Netlink::VLAN_FLAG_LOOSE_BINDING,
# :vlan_mask=>0xffffffff
# )
def add_vlan(opt)
add_link(vlan_options(opt))
end
def change_vlan(opt)
change_link(vlan_options(opt))
end
def replace_vlan(opt)
replace_link(vlan_options(opt))
end
# Delete vlan given :link and :vlan_id. If you want to delete
# by :index then call delete_link instead.
def delete_vlan(opt)
raise "Missing vlan_id" unless opt[:vlan_id]
raise "Missing link" unless opt[:link]
link = links(:kind=>"vlan", :link=>opt[:link]).find { |l|
l.linkinfo.data &&
l.linkinfo.data.id == opt[:vlan_id]
}
raise Errno::ENODEV unless link
delete_link(link.index)
end
def vlan_options(orig) #:nodoc:
opt = orig.dup
opt[:link] = index(opt.fetch(:link))
li = opt[:linkinfo] ||= LinkInfo.new
li.kind = "vlan"
li.data ||= VlanInfo.new
li.data.id = opt.delete(:vlan_id) if opt.has_key?(:vlan_id)
if opt.has_key?(:vlan_flags)
li.data.flags ||= VlanFlags.new(:flags => opt.delete(:vlan_flags))
li.data.flags.mask = opt.delete(:vlan_mask) if opt.has_key?(:vlan_mask)
end
li.data.egress_qos = opt.delete(:egress_qos) if opt.has_key?(:egress_qos)
li.data.ingress_qos = opt.delete(:ingress_qos) if opt.has_key?(:ingress_qos)
opt
end
# Return the memoized address table, keyed by interface name and
# address family, containing an array of addresses for each
# interface/family combination. i.e.
#
# # {ifname=>{family=>[addr,addr,...], ...}, ...}
# puts rt.addrs["eth0"][Socket::AF_INET][0].address
#
# If there are no addresses for a particular family then it will
# return a (frozen) empty array, to make iteration eaiser.
def addrs
@addrs ||= (
h = {}
links do |link|
h[link.ifname] = {}
end
read_addrs.each do |addr|
ifname = name(addr.index)
h[ifname] ||= Hash.new(EMPTY_ARRAY)
(h[ifname][addr.family] ||= []) << addr
end
h
)
end
# Add an IP address to an interface
#
# require 'netlink/route'
# rt = Netlink::Route::Socket.new
# rt.add_addr(:index=>"eth0", :local=>"1.2.3.4", :prefixlen=>24)
def add_addr(opt)
ipaddr_modify(RTM_NEWADDR, NLM_F_CREATE|NLM_F_EXCL, opt)
end
def change_addr(opt)
ipaddr_modify(RTM_NEWADDR, NLM_F_REPLACE, opt)
end
def replace_addr(opt)
ipaddr_modify(RTM_NEWADDR, NLM_F_CREATE|NLM_F_REPLACE, opt)
end
# Delete an IP address from an interface. Pass in either a hash of
# parameters, or an existing IFAddr object.
def delete_addr(opt)
ipaddr_modify(RTM_DELADDR, 0, opt)
end
def ipaddr_modify(code, flags, msg) #:nodoc:
msg = IFAddr.new(msg)
msg.index = index(msg.index) unless msg.index.is_a?(Integer)
msg.address ||= msg.local
# Note: IPAddr doesn't support addresses off the subnet base,
# so there's no point trying to set msg.prefixlen from the IPAddr mask
@nlsocket.cmd code, msg, flags|NLM_F_REQUEST
clear_addr_cache
end
end
end
end