summaryrefslogtreecommitdiff
path: root/lib/drb/acl.rb
blob: 861c8a514d20bf21f0988160911cc3c9e7390f72 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
# acl-2.0 - simple Access Control List
#
# Copyright (c) 2000,2002,2003 Masatoshi SEKI
#
# acl.rb is copyrighted free software by Masatoshi SEKI.
# You can redistribute it and/or modify it under the same terms as Ruby.

require 'ipaddr'

class ACL
  VERSION=["2.0.0"]
  class ACLEntry
    def initialize(str)
      if str == '*' or str == 'all'
	@pat = [:all]
      elsif str.include?('*')
        @pat = [:name, dot_pat(str)]
      else
	begin
	  @pat = [:ip, IPAddr.new(str)]
	rescue ArgumentError
	  @pat = [:name, dot_pat(str)]
	end
      end
    end

    private
    def dot_pat_str(str)
      list = str.split('.').collect { |s|
	(s == '*') ? '.+' : s
      }
      list.join("\\.")
    end

    private
    def dot_pat(str)
      exp = "^" + dot_pat_str(str) + "$"
      Regexp.new(exp)
    end

    public
    def match(addr)
      case @pat[0]
      when :all
	true
      when :ip
	begin
	  ipaddr = IPAddr.new(addr[3])
	  ipaddr = ipaddr.ipv4_mapped if @pat[1].ipv6? && ipaddr.ipv4?
	rescue ArgumentError
	  return false
	end
	(@pat[1].include?(ipaddr)) ? true : false
      when :name
	(@pat[1] =~ addr[2]) ? true : false
      else
	false
      end
    end
  end

  class ACLList
    def initialize
      @list = []
    end

    public
    def match(addr)
      @list.each do |e|
	return true if e.match(addr)
      end
      false
    end

    public
    def add(str)
      @list.push(ACLEntry.new(str))
    end
  end

  DENY_ALLOW = 0
  ALLOW_DENY = 1

  def initialize(list=nil, order = DENY_ALLOW)
    @order = order
    @deny = ACLList.new
    @allow = ACLList.new
    install_list(list) if list
  end

  public
  def allow_socket?(soc)
    allow_addr?(soc.peeraddr)
  end

  public
  def allow_addr?(addr)
    case @order
    when DENY_ALLOW
      return true if @allow.match(addr)
      return false if @deny.match(addr)
      return true
    when ALLOW_DENY
      return false if @deny.match(addr)
      return true if @allow.match(addr)
      return false
    else
      false
    end
  end

  public
  def install_list(list)
    i = 0
    while i < list.size
      permission, domain = list.slice(i,2)
      case permission.downcase
      when 'allow'
	@allow.add(domain)
      when 'deny'
	@deny.add(domain)
      else
	raise "Invalid ACL entry #{list.to_s}"
      end
      i += 2
    end
  end
end

if __FILE__ == $0
  # example
  list = %w(deny all
	    allow 192.168.1.1
            allow ::ffff:192.168.1.2
            allow 192.168.1.3
            )

  addr = ["AF_INET", 10, "lc630", "192.168.1.3"]

  acl = ACL.new
  p acl.allow_addr?(addr)

  acl = ACL.new(list, ACL::DENY_ALLOW)
  p acl.allow_addr?(addr)
end