/
iac.go
265 lines (245 loc) · 7.39 KB
/
iac.go
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
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
package mud
import (
"bytes"
"fmt"
)
// IANA 管理的 Telnet 选项分配情况：
// https://www.iana.org/assignments/telnet-options/telnet-options.xhtml
// Standard Telnet Commands ，参见 https://tools.ietf.org/html/rfc854
const (
IAC = 255 // 0xFF Interpret as Command
DONT = 254 // 0xFE Don't do something
DO = 253 // 0xFD Do something
WONT = 252 // 0xFC Won't do something
WILL = 251 // 0xFB Will do something
SB = 250 // 0xFA Subnegotiation Begin
GA = 249 // 0xF9 Go Ahead
EL = 248 // 0xF8 Erase Line
EC = 247 // 0xF7 Erase Character
AYT = 246 // 0xF6 Are You Here?
AO = 245 // 0xF5 Abort Output
IP = 244 // 0xF4 Interrupt Process
BREAK = 243 // 0xF3 NVT character BRK
DM = 242 // 0xF2 Data Mark
NOP = 241 // 0xF1 No Operation
SE = 240 // 0xF0 Subnegotiation End
)
// Standard Telnet Commands: https://tools.ietf.org/html/rfc854
const (
EOR = 239 // 0xEF End Of Record
OptEOR = 25 // 0x19 Negotiate About EOR
)
// Telnet Linemode Option: https://tools.ietf.org/html/rfc1116
const (
LMABORT = 238 // 0xEE (Linemode) Abort
LMSUSP = 237 // 0xED (Linemode) Suspend
LMEOF = 236 // 0xEC (Linemode) End Of File
OptLINEMODE = 34 // 0x22 Linemode Option
)
const (
OptBINARY = 0 // 0x00 [RFC856] Binary Transmission
OptECHO = 1 // 0x01 [RFC857] Echo
OptRCP = 2 // 0x02 [NIC5005] Telnet Reconnection Option
OptNAOL = 8 // 0x08 [NIC5005] Negotiate About Output Line Width
OptNAOP = 9 // 0x09 [NIC5005] Negotiate About Output Page Size
OptSGA = 3 // 0x03 [RFC858] Suppress GA (Go Ahead)
OptNAMS = 4 // 0x04 [ ] Negotiate About Message Size
OptSTATUS = 5 // 0x05 [RFC859] Status
OptTM = 6 // 0x06 [RFC860] Timing Mark
OptRCTE = 7 // 0x07 [RFC726] Remote Controlled Transmssion and Echoing
OptNAOCRD = 10 // 0x0A [RFC652] Negotiate About Output Carriage-Return Disposition
OptNAOHTS = 11 // 0x0B [RFC653] Negotiate About Output Horizontal Tab Stops
OptNAOHTD = 12 // 0x0C [RFC654] Negotiate About Output Horizontal Tab Disposition
OptNAOFFD = 13 // 0x0D [RFC655] Negotiate About Output Formfeed Disposition
OptNAOVTS = 14 // 0x0E [RFC656] Negotiate About Output Vertical Tabstops
OptNAOVTD = 15 // 0x0F [RFC657] Negotiate About Output Vertical Tab Disposition
OptNAOLFD = 16 // 0x10 [RFC658] Negotiate About Output Linefeed Disposition
OptXASCII = 17 // 0x11 [RFC698] Extended ASCII
OptLOGOUT = 18 // 0x12 [RFC727] Logout
OptBM = 19 // 0x13 [RFC735] Byte Macro
OptDET = 20 // 0x14 [RFC1043] Data Entry Terminal
OptSUPDUP = 21 // 0x15 [RFC736] SUPDUP Display Protocol
OptSUPDUPOUT = 22 // 0x16 [RFC749] SUPDUP OUTPUT
OptSNDLOC = 23 // 0x17 [RFC779] Send Location
OptTTYPE = 24 // 0x18 [RFC1091] Terminal Type
OptTUID = 26 // 0x1A [RFC927] TACACS User Identification
OptOUTMRK = 27 // 0x1B [RFC933] Output Marking
OptTTYLOC = 28 // 0x1C [RFC946] Terminal Location Number
Opt3270 = 29 // 0x1D [RFC1041] Telnet 3270 Regime
OptX3PAD = 30 // 0x1E [RFC1053] X.3 PAD
OptNAWS = 31 // 0x1F [RFC1073] Negotiate About Window Size
OptTSPEED = 32 // 0x20 [RFC1079] Terminal Speed
OptLFLOW = 33 // 0x21 [RFC1372] Remote Flow Control
OptXDISPLOC = 35 // 0x23 [RFC1096] X Display Location
OptENVIRON = 36 // 0x24 [RFC1408] Environment Option
OptAUTH = 37 // 0x25 [RFC2941] Authentication Option
OptENCRYPT = 38 // 0x26 [RFC2946] Encryption Option
OptNENV = 39 // 0x27 [RFC1572] New Environment
OptTN3270E = 40 // 0x28 [RFC2355] TN3270 Enhancements
OptXAUTH = 41 // 0x29
OptCHARSET = 42 // 0x30 [RFC2066] Charset Option
OptCOMPORT = 44 // 0x32 [RFC2217] Com Port Control Option
OptKERMIT = 47 // 0x35 [RFC2840] KERMIT Option
OptMSSP = 70 // 0x46 MUD Server Status Protocol
OptMCCP = 85 // 0x55 MUD Client Compression Protocol
OptMCCP2 = 86 // 0x56 MUD Client Compression Protocol 2.0
OptMXP = 91 // 0x5B MUD eXtension Protocol
OptZMP = 93 // 0x5D Zenith MUD Protocol
OptGMCP = 201 // 0xC9 Generic MUD Communication Protocol
OptEXOPL = 255 // 0xFF Extended Options List
)
var codeName = map[byte]string{
IAC: "IAC",
DONT: "DONT",
DO: "DO",
WONT: "WONT",
WILL: "WILL",
SB: "SB",
GA: "GA",
EL: "EL",
EC: "EC",
AYT: "AYT",
AO: "AO",
IP: "IP",
BREAK: "BREAK",
DM: "DM",
NOP: "NOP",
SE: "SE",
EOR: "EOR",
LMABORT: "ABORT",
LMSUSP: "SUSP",
LMEOF: "EOF",
OptBINARY: "BINARY",
OptECHO: "ECHO",
OptRCP: "RCP",
OptSGA: "SGA",
OptNAMS: "NAMS",
OptSTATUS: "STATUS",
OptTM: "TM",
OptRCTE: "RCTE",
OptNAOL: "NAOL",
OptNAOP: "NAOP",
OptNAOCRD: "NAOCRD",
OptNAOHTS: "NAOHTS",
OptNAOHTD: "NAOHTD",
OptNAOFFD: "NAOFFD",
OptNAOVTS: "NAOVTS",
OptNAOVTD: "NAOVTD",
OptNAOLFD: "NAOLFD",
OptXASCII: "XASCII",
OptLOGOUT: "LOGOUT",
OptBM: "BM",
OptDET: "DET",
OptSUPDUP: "SUP",
OptSUPDUPOUT: "SUPOUT",
OptSNDLOC: "SNDLOC",
OptTTYPE: "TTYPE",
OptEOR: "EOR",
OptTUID: "TUID",
OptOUTMRK: "OUTMRK",
OptTTYLOC: "TTYLOC",
Opt3270: "3270",
OptX3PAD: "X3PAD",
OptNAWS: "NAWS",
OptTSPEED: "TSPEED",
OptLFLOW: "LFLOW",
OptLINEMODE: "LINEMODE",
OptXDISPLOC: "XDISPLOC",
OptENVIRON: "ENVIRON",
OptAUTH: "AUTH",
OptENCRYPT: "ENCRYPT",
OptNENV: "NENV",
OptTN3270E: "TN3270E",
OptXAUTH: "XAUTH",
OptCHARSET: "CHARSET",
OptCOMPORT: "COMPORT",
OptKERMIT: "KERMIT",
OptMSSP: "MSSP",
OptMCCP: "MCCP",
OptMCCP2: "MCCP2",
OptMXP: "MXP",
OptZMP: "ZMP",
OptGMCP: "GMCP",
}
type iacStage int
const (
stCmd iacStage = iota
stArg
stSuboption
stDone
)
type IACMessage struct {
state iacStage
Command byte
Args []byte
}
func NewIACMessage() *IACMessage {
iac := &IACMessage{}
iac.Reset()
return iac
}
func (IACMessage) IsMessage() {}
func (iac *IACMessage) Reset() {
iac.state = stCmd
iac.Args = make([]byte, 0, 128)
}
func (iac IACMessage) String() string {
cmdName := codeName[iac.Command]
if cmdName == "" {
cmdName = fmt.Sprintf("%d", iac.Command)
}
argName := fmt.Sprintf("%v", iac.Args[:len(iac.Args)])
if (iac.Command == WILL ||
iac.Command == WONT ||
iac.Command == DO ||
iac.Command == DONT ||
iac.Command == SB) &&
codeName[iac.Args[0]] != "" {
argName = codeName[iac.Args[0]]
}
return fmt.Sprintf("IAC %s %s", cmdName, argName)
}
func (iac IACMessage) Eq(command byte, args ...byte) bool {
if iac.Command != command {
return false
}
return bytes.Equal(iac.Args, args)
}
func (iac *IACMessage) Scan(b byte) (completed bool) {
switch iac.state {
case stCmd:
switch b {
case WILL, WONT, DO, DONT:
iac.Command = b
iac.state = stArg
return false
case SB:
iac.Command = SB
iac.state = stSuboption
return false
case SE:
iac.Command = SE
iac.state = stDone
return true
case GA:
iac.Command = GA
iac.state = stDone
return true
default:
// TODO: 需要处理未知 IAC 指令
iac.state = stDone
return true
}
case stArg:
iac.Args = append(iac.Args, b)
iac.state = stDone
return true
case stSuboption:
iac.Args = append(iac.Args, b)
return false
default:
iac.state = stDone
// TODO: 需要处理未知 IAC 指令
return true
}
}