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
|
# SNMP v1 & v2c security models implementation
from pyasn1.codec.ber import encoder
from pysnmp.proto.secmod import base
from pysnmp.smi.error import NoSuchInstanceError
from pysnmp.proto import error
class SnmpV1SecurityModel(base.AbstractSecurityModel):
securityModelID = 1
# According to rfc2576, community name <-> contextEngineId/contextName
# mapping is up to MP module for notifications but belongs to secmod
# responsibility for other PDU types. Since I do not yet understand
# the reason for this de-coupling, I've moved this code from MP-scope
# in here.
def generateRequestMsg(
self,
snmpEngine,
messageProcessingModel,
globalData,
maxMessageSize,
securityModel,
securityEngineId,
securityName,
securityLevel,
scopedPDU
):
msg, = globalData
contextEngineId, contextName, pdu = scopedPDU
# rfc2576: 5.2.3
( snmpCommunityName,
snmpCommunitySecurityName,
snmpCommunityContextEngineId,
snmpCommunityContextName ) = snmpEngine.msgAndPduDsp.mibInstrumController.mibBuilder.importSymbols(
'SNMP-COMMUNITY-MIB',
'snmpCommunityName',
'snmpCommunitySecurityName',
'snmpCommunityContextEngineID',
'snmpCommunityContextName'
)
mibNodeIdx = snmpCommunitySecurityName
while 1:
try:
mibNodeIdx = snmpCommunitySecurityName.getNextNode(
mibNodeIdx.name
)
except NoSuchInstanceError:
break
if mibNodeIdx.syntax != securityName:
continue
instId = mibNodeIdx.name[len(snmpCommunitySecurityName.name):]
mibNode = snmpCommunityContextEngineId.getNode(
snmpCommunityContextEngineId.name + instId
)
if mibNode.syntax != contextEngineId:
continue
mibNode = snmpCommunityContextName.getNode(
snmpCommunityContextName.name + instId
)
if mibNode.syntax != contextName:
continue
# XXX TODO: snmpCommunityTransportTag
mibNode = snmpCommunityName.getNode(
snmpCommunityName.name + instId
)
securityParameters = mibNode.syntax
msg.setComponentByPosition(1, securityParameters)
msg.setComponentByPosition(2)
msg.getComponentByPosition(2).setComponentByType(pdu.tagSet, pdu)
wholeMsg = encoder.encode(msg)
return ( securityParameters, wholeMsg )
raise error.StatusInformation(
errorIndication = 'unknownCommunityName'
)
def generateResponseMsg(
self,
snmpEngine,
messageProcessingModel,
globalData,
maxMessageSize,
securityModel,
securityEngineID,
securityName,
securityLevel,
scopedPDU,
securityStateReference
):
# rfc2576: 5.2.2
msg, = globalData
contextEngineId, contextName, pdu = scopedPDU
cachedSecurityData = self._cachePop(securityStateReference)
communityName = cachedSecurityData['communityName']
msg.setComponentByPosition(1, communityName)
msg.setComponentByPosition(2)
msg.getComponentByPosition(2).setComponentByType(pdu.tagSet, pdu)
wholeMsg = encoder.encode(msg)
return ( communityName, wholeMsg )
def processIncomingMsg(
self,
snmpEngine,
messageProcessingModel,
maxMessageSize,
securityParameters,
securityModel,
securityLevel,
wholeMsg,
msg
):
# rfc2576: 5.2.1
( communityName, srcTransport, destTransport ) = securityParameters
( snmpCommunityName,
snmpCommunitySecurityName,
snmpCommunityContextEngineId,
snmpCommunityContextName
) = snmpEngine.msgAndPduDsp.mibInstrumController.mibBuilder.importSymbols(
'SNMP-COMMUNITY-MIB',
'snmpCommunityName',
'snmpCommunitySecurityName',
'snmpCommunityContextEngineID',
'snmpCommunityContextName'
)
mibNodeIdx = snmpCommunityName
while 1:
try:
mibNodeIdx = snmpCommunityName.getNextNode(
mibNodeIdx.name
)
except NoSuchInstanceError:
break
if mibNodeIdx.syntax != communityName:
continue
break
else:
snmpInBadCommunityNames, = snmpEngine.msgAndPduDsp.mibInstrumController.mibBuilder.importSymbols('SNMP-COMMUNITY-MIB', 'snmpInBadCommunityNames')
snmpInBadCommunityNames.syntax = snmpInBadCommunityNames.syntax+1
raise error.StatusInformation(
errorIndication = 'unknownCommunityName'
)
# XXX TODO: snmpCommunityTransportTag
instId = mibNodeIdx.name[len(snmpCommunityName.name):]
communityName = snmpCommunityName.getNode(
snmpCommunityName.name + instId
)
securityName = snmpCommunitySecurityName.getNode(
snmpCommunitySecurityName.name + instId
)
contextEngineId = snmpCommunityContextEngineId.getNode(
snmpCommunityContextEngineId.name + instId
)
contextName = snmpCommunityContextName.getNode(
snmpCommunityContextName.name + instId
)
snmpEngineID, = snmpEngine.msgAndPduDsp.mibInstrumController.mibBuilder.importSymbols(
'SNMP-FRAMEWORK-MIB', 'snmpEngineID'
)
stateReference = self._cachePush(
communityName=communityName.syntax
)
securityEngineID = snmpEngineID.syntax
securityName = securityName.syntax
scopedPDU = (
contextEngineId.syntax, contextName.syntax,
msg.getComponentByPosition(2).getComponent()
)
maxSizeResponseScopedPDU = maxMessageSize - 128
securityStateReference = stateReference
return ( securityEngineID,
securityName,
scopedPDU,
maxSizeResponseScopedPDU,
securityStateReference )
class SnmpV2cSecurityModel(SnmpV1SecurityModel):
securityModelID = 2
# XXX
# contextEngineId/contextName goes to globalData
|