Files
netlinkrb/lib/linux/netlink/route/addr_handler.rb

137 lines
4.8 KiB
Ruby

require 'linux/netlink/route'
require 'linux/netlink/route/handler'
module Linux
module Netlink
# 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 iaddresses.
class AddrHandler < Handler
def clear_cache
@addr = nil
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_addr(:family => Socket::AF_INET)
# p res
# [#<Linux::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_addr(opt=nil, &blk)
@rtsocket.send_request RTM_GETADDR, IFAddr.new(opt),
NLM_F_ROOT | NLM_F_MATCH | NLM_F_REQUEST
@rtsocket.receive_until_done(RTM_NEWADDR, &blk)
end
class Filter < BaseFilter #:nodoc:
filter(:family) { |o,v| o.family == v }
filter(:scope) { |o,v| o.scope == scope }
filter(:flags) { |o,v| (o.flags & v) == v }
filter(:noflags) { |o,v| (o.flags & v) == 0 }
filter(:index) { |o,v| o.index == v }
end
# Iterate over all addresses, or addressees matching the given
# criteria. Returns an Enumerator if no block given.
#
# The full address list is read once and memoized, so
# it is efficient to call this method multiple times.
#
# nl.addr.list { |x| p x }
# addrs_eth0 = nl.addr.list(:index=>"eth0").to_a
# addrs_eth0_v4 = nl.addr.list(:index=>"eth0", :family=>Socket::AF_INET).to_a
def list(filter=nil, &blk)
@addr ||= read_addr
filter[:index] = index(filter[:index]) if filter && filter.has_key?(:index)
filter_list(@addr, filter, &blk)
end
alias :each :list
# Return addresses grouped by interface name. e.g.
# group_by_interface(:family => Socket::AF_INET).to_a
# #=> {"eth0"=>[addr, addr,...], "lo"=>[addr, addr,...]
#
# The hash has an empty array as its default, so it's safe to do
# group_by_interface(...)["eth0"].each { |a| ... }
# even if eth0 has no addresses matching the given filter.
def group_by_interface(*filter)
res = list(*filter).group_by { |a| ifname(a.index) }
res.default = EMPTY_ARRAY
res
end
# Add an IP address to an interface
#
# require 'netlink/route'
# ip = Linux::Netlink::Route::Socket.new
# ip.addr.add(:index=>"eth0", :local=>"1.2.3.4", :prefixlen=>24)
def add(opt)
ipaddr_modify(RTM_NEWADDR, NLM_F_CREATE|NLM_F_EXCL, opt)
end
def change(opt)
ipaddr_modify(RTM_NEWADDR, NLM_F_REPLACE, opt)
end
def replace(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(opt)
ipaddr_modify(RTM_DELADDR, 0, opt)
end
SCOPES = {
:global => 0,
:nowhere => 1,
:host => 254,
:link => 253,
:site => 200
}
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
msg.scope = SCOPES[msg.scope.to_s.downcase.to_sym] if
msg.scope && !msg.scope.is_a?(Integer)
# Note: IPAddr doesn't support addresses off the subnet base,
# so there's no point trying to set msg.prefixlen from the IPAddr mask
@rtsocket.cmd code, msg, flags|NLM_F_REQUEST
clear_cache
end
end
end
end
end # module Linux