Add missing SNMP PDU error classes

Added missing SNMP PDU error classes and their handling in
Command Responder

4 files changed, 70 insertions, 14 deletions

diff --git a/CHANGES.txt b/CHANGES.txt
index 7f7e7618..1b5b75fd 100644
--- a/CHANGES.txt
+++ b/CHANGES.txt
@@ -3,6 +3,7 @@ Revision 4.4.9, released 2019-01-XX
 -----------------------------------
 
 - Made MIB loader ignoring file and directory access errors
+- Added missing SNMP PDU error classes and their handling in Command Responder
 - Fixed crash on MIB load failure in case of directory access error
 - Fixed socket transparency option (IPV6_TRANSPARENT)to make IPv6
   transparent operation functional
diff --git a/pysnmp/entity/rfc3413/cmdrsp.py b/pysnmp/entity/rfc3413/cmdrsp.py
index 3e1db4f3..5cef0a14 100644
--- a/pysnmp/entity/rfc3413/cmdrsp.py
+++ b/pysnmp/entity/rfc3413/cmdrsp.py
@@ -138,6 +138,7 @@ class CommandResponderBase(object):
             self.handleMgmtOperation(snmpEngine, stateReference,
                                      contextName, PDU,
                                      (self.__verifyAccess, snmpEngine))
+
         # SNMPv2 SMI exceptions
         except pysnmp.smi.error.GenError:
             errorIndication = sys.exc_info()[1]
@@ -148,38 +149,72 @@ class CommandResponderBase(object):
                 statusInformation['oid'] = errorIndication['oid']
                 statusInformation['val'] = errorIndication['val']
 
-        # PDU-level SMI errors
+        # Handle PDU-level SMI errors
+
+        except pysnmp.smi.error.TooBigError:
+            errorStatus, errorIndex = 'tooBig', 0
+            # rfc1905: 4.2.1.3
+            varBinds = []
+
+        # this should never bubble up, SNMP exception objects should be passed as values
+        except pysnmp.smi.error.NoSuchNameError:
+            errorStatus, errorIndex = 'noSuchName', sys.exc_info()[1]['idx'] + 1
+
+        except pysnmp.smi.error.BadValueError:
+            errorStatus, errorIndex = 'badValue', sys.exc_info()[1]['idx'] + 1
+
+        except pysnmp.smi.error.ReadOnlyError:
+            errorStatus, errorIndex = 'readOnly', sys.exc_info()[1]['idx'] + 1
+
+        except pysnmp.smi.error.GenError:
+            errorStatus, errorIndex = 'genErr', sys.exc_info()[1]['idx'] + 1
+
         except pysnmp.smi.error.NoAccessError:
             errorStatus, errorIndex = 'noAccess', sys.exc_info()[1]['idx'] + 1
+
         except pysnmp.smi.error.WrongTypeError:
             errorStatus, errorIndex = 'wrongType', sys.exc_info()[1]['idx'] + 1
+
         except pysnmp.smi.error.WrongLengthError:
             errorStatus, errorIndex = 'wrongLength', sys.exc_info()[1]['idx'] + 1
+
         except pysnmp.smi.error.WrongEncodingError:
             errorStatus, errorIndex = 'wrongEncoding', sys.exc_info()[1]['idx'] + 1
+
         except pysnmp.smi.error.WrongValueError:
             errorStatus, errorIndex = 'wrongValue', sys.exc_info()[1]['idx'] + 1
+
         except pysnmp.smi.error.NoCreationError:
             errorStatus, errorIndex = 'noCreation', sys.exc_info()[1]['idx'] + 1
+
         except pysnmp.smi.error.InconsistentValueError:
             errorStatus, errorIndex = 'inconsistentValue', sys.exc_info()[1]['idx'] + 1
+
         except pysnmp.smi.error.ResourceUnavailableError:
             errorStatus, errorIndex = 'resourceUnavailable', sys.exc_info()[1]['idx'] + 1
+
         except pysnmp.smi.error.CommitFailedError:
             errorStatus, errorIndex = 'commitFailed', sys.exc_info()[1]['idx'] + 1
+
         except pysnmp.smi.error.UndoFailedError:
             errorStatus, errorIndex = 'undoFailed', sys.exc_info()[1]['idx'] + 1
+
         except pysnmp.smi.error.AuthorizationError:
             errorStatus, errorIndex = 'authorizationError', sys.exc_info()[1]['idx'] + 1
+
         except pysnmp.smi.error.NotWritableError:
             errorStatus, errorIndex = 'notWritable', sys.exc_info()[1]['idx'] + 1
+
         except pysnmp.smi.error.InconsistentNameError:
             errorStatus, errorIndex = 'inconsistentName', sys.exc_info()[1]['idx'] + 1
+
         except pysnmp.smi.error.SmiError:
-            errorStatus, errorIndex = 'genErr', len(varBinds) and 1 or 0
+            errorStatus, errorIndex = 'genErr', len(varBinds) and 1
+
         except pysnmp.error.PySnmpError:
             self.releaseStateInformation(stateReference)
             return
+
         else:  # successful request processor must release state info
             return
 
diff --git a/pysnmp/proto/rfc1905.py b/pysnmp/proto/rfc1905.py
index 4a229495..d5da3982 100644
--- a/pysnmp/proto/rfc1905.py
+++ b/pysnmp/proto/rfc1905.py
@@ -84,12 +84,13 @@ class VarBindList(univ.SequenceOf):
 
 
 errorStatus = univ.Integer(
-    namedValues=namedval.NamedValues(('noError', 0), ('tooBig', 1), ('noSuchName', 2), ('badValue', 3), ('readOnly', 4),
-                                     ('genErr', 5), ('noAccess', 6), ('wrongType', 7), ('wrongLength', 8),
-                                     ('wrongEncoding', 9), ('wrongValue', 10), ('noCreation', 11),
-                                     ('inconsistentValue', 12), ('resourceUnavailable', 13), ('commitFailed', 14),
-                                     ('undoFailed', 15), ('authorizationError', 16), ('notWritable', 17),
-                                     ('inconsistentName', 18))
+    namedValues=namedval.NamedValues(
+        ('noError', 0), ('tooBig', 1), ('noSuchName', 2), ('badValue', 3), ('readOnly', 4),
+        ('genErr', 5), ('noAccess', 6), ('wrongType', 7), ('wrongLength', 8),
+        ('wrongEncoding', 9), ('wrongValue', 10), ('noCreation', 11),
+        ('inconsistentValue', 12), ('resourceUnavailable', 13), ('commitFailed', 14),
+        ('undoFailed', 15), ('authorizationError', 16), ('notWritable', 17),
+        ('inconsistentName', 18))
     )
 
 
diff --git a/pysnmp/smi/error.py b/pysnmp/smi/error.py
index 4b7ba5cc..a16dfe2b 100644
--- a/pysnmp/smi/error.py
+++ b/pysnmp/smi/error.py
@@ -43,7 +43,24 @@ class MibOperationError(SmiError):
         self.__outArgs.update(d)
 
 
-# Aligned with SNMPv2 PDU error-status
+# Aligned with SNMPv2 PDU error-status values
+
+class TooBigError(MibOperationError):
+    pass
+
+
+class NoSuchNameError(MibOperationError):
+    pass
+
+
+class BadValueError(MibOperationError):
+    pass
+
+
+class ReadOnlyError(MibOperationError):
+    pass
+
+
 class GenError(MibOperationError):
     pass
 
@@ -100,20 +117,22 @@ class InconsistentNameError(MibOperationError):
     pass
 
 
-# Aligned with SNMPv2 Var-Bind exceptions
-class NoSuchObjectError(MibOperationError):
+# Aligned with SNMPv2 PDU exceptions or error-status values
+
+class NoSuchObjectError(NoSuchNameError):
     pass
 
 
-class NoSuchInstanceError(MibOperationError):
+class NoSuchInstanceError(NoSuchNameError):
     pass
 
 
-class EndOfMibViewError(MibOperationError):
+class EndOfMibViewError(NoSuchNameError):
     pass
 
 
-# Row management
+# SNMP table management exceptions
+
 class TableRowManagement(MibOperationError):
     pass