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
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
|
# -*- coding: binary -*-
require 'ipaddr'
module PacketFu
# AddrIpv6 handles addressing for IPv6Header
#
# ==== Header Definition
#
# Int32 :a1
# Int32 :a2
# Int32 :a3
# Int32 :a4
class AddrIpv6 < Struct.new(:a1, :a2, :a3, :a4)
include StructFu
def initialize(args={})
super(
Int32.new(args[:a1]),
Int32.new(args[:a2]),
Int32.new(args[:a3]),
Int32.new(args[:a4]))
end
# Returns the address in string format.
def to_s
self.to_a.map {|x| x.to_s}.join
end
# Returns the address as a fairly ginormous integer.
def to_i
(a1.to_i << 96) + (a2.to_i << 64) + (a3.to_i << 32) + a4.to_i
end
# Returns the address as a colon-delimited hex string.
def to_x
IPAddr.new(self.to_i, Socket::AF_INET6).to_s
end
# Reads in a string and casts it as an IPv6 address
def read(str)
force_binary(str)
return self if str.nil?
self[:a1].read str[0,4]
self[:a2].read str[4,4]
self[:a3].read str[8,4]
self[:a4].read str[12,4]
self
end
# Reads in a colon-delimited hex string and casts it as an IPv6 address.
def read_x(str)
addr = IPAddr.new(str).to_i
self[:a1]=Int32.new(addr >> 96)
self[:a2]=Int32.new((addr & 0x00000000ffffffff0000000000000000) >> 64)
self[:a3]=Int32.new((addr & 0x0000000000000000ffffffff00000000) >> 32)
self[:a4]=Int32.new(addr & 0x000000000000000000000000ffffffff)
self
end
end
# IPv6Header is complete IPv6 struct, used in IPv6Packet.
#
# ==== Header Definition
#
# Integer(4 bits) :ipv6_v Default: 6 # Versiom
# Integer(8 bits) :ipv6_class Defualt: 0 # Class
# Integer(20 bits) :ipv6_label Defualt: 0 # Label
# Int16 :ipv6_len Default: calc # Payload length
# Int8 :ipv6_next # Next Header
# Int8 :ipv6_hop Default: 0xff # Hop limit
# AddrIpv6 :ipv6_src
# AddrIpv6 :ipv6_dst
# String :body
class IPv6Header < Struct.new(:ipv6_v, :ipv6_class, :ipv6_label,
:ipv6_len, :ipv6_next, :ipv6_hop,
:ipv6_src, :ipv6_dst, :body)
include StructFu
def initialize(args={})
super(
(args[:ipv6_v] || 6),
(args[:ipv6_class] || 0),
(args[:ipv6_label] || 0),
Int16.new(args[:ipv6_len]),
Int8.new(args[:ipv6_next]),
Int8.new(args[:ipv6_hop] || 0xff),
AddrIpv6.new.read(args[:ipv6_src] || ("\x00" * 16)),
AddrIpv6.new.read(args[:ipv6_dst] || ("\x00" * 16)),
StructFu::String.new.read(args[:body])
)
end
# Returns the object in string form.
def to_s
bytes_v_class_label = [(self.ipv6_v << 28) +
(self.ipv6_class << 20) +
self.ipv6_label].pack("N")
bytes_v_class_label + (self.to_a[3,6].map {|x| x.to_s}.join)
end
# Reads a string to populate the object.
def read(str)
force_binary(str)
return self if str.nil?
self[:ipv6_v] = str[0,1].unpack("C").first >> 4
self[:ipv6_class] = (str[0,2].unpack("n").first & 0x0ff0) >> 4
self[:ipv6_label] = str[0,4].unpack("N").first & 0x000fffff
self[:ipv6_len].read(str[4,2])
self[:ipv6_next].read(str[6,1])
self[:ipv6_hop].read(str[7,1])
self[:ipv6_src].read(str[8,16])
self[:ipv6_dst].read(str[24,16])
self[:body].read(str[40,str.size]) if str.size > 40
self
end
# Setter for the version (usually, 6).
def ipv6_v=(i); self[:ip_v] = i.to_i; end
# Getter for the version (usually, 6).
def ipv6_v; self[:ipv6_v].to_i; end
# Setter for the traffic class.
def ipv6_class=(i); self[:ip_class] = i.to_i; end
# Getter for the traffic class.
def ipv6_class; self[:ipv6_class].to_i; end
# Setter for the flow label.
def ipv6_label=(i); self[:ip_label] = i.to_i; end
# Getter for the flow label.
def ipv6_label; self[:ipv6_label].to_i; end
# Setter for the payload length.
def ipv6_len=(i); typecast i; end
# Getter for the payload length.
def ipv6_len; self[:ipv6_len].to_i; end
# Setter for the next protocol header.
def ipv6_next=(i); typecast i; end
# Getter for the next protocol header.
def ipv6_next; self[:ipv6_next].to_i; end
# Setter for the hop limit.
def ipv6_hop=(i); typecast i; end
# Getter for the hop limit.
def ipv6_hop; self[:ipv6_hop].to_i; end
# Setter for the source address.
def ipv6_src=(i); typecast i; end
# Getter for the source address.
def ipv6_src; self[:ipv6_src].to_i; end
# Setter for the destination address.
def ipv6_dst=(i); typecast i; end
# Getter for the destination address.
def ipv6_dst; self[:ipv6_dst].to_i; end
# Calculates the payload length.
def ipv6_calc_len
self.ipv6_len = body.to_s.length
end
# Recalculates the calculatable fields for this object.
def ipv6_recalc(arg=:all)
case arg
when :ipv6_len
ipv6_calc_len
when :all
ipv6_recalc(:ipv6_len)
end
end
# Get the source address in a more readable form.
def ipv6_saddr
self[:ipv6_src].to_x
end
# Set the source address in a more readable form.
def ipv6_saddr=(str)
self[:ipv6_src].read_x(str)
end
# Get the destination address in a more readable form.
def ipv6_daddr
self[:ipv6_dst].to_x
end
# Set the destination address in a more readable form.
def ipv6_daddr=(str)
self[:ipv6_dst].read_x(str)
end
# Readability aliases
alias :ipv6_src_readable :ipv6_saddr
alias :ipv6_dst_readable :ipv6_daddr
end # class IPv6Header
end
|
