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|
#
# python-netsnmpagent module
# Copyright (c) 2013-2016 Pieter Hollants <pieter@hollants.com>
# Licensed under the GNU Lesser Public License (LGPL) version 3
#
# net-snmp C API abstraction module
#
import ctypes, ctypes.util
c_sizet_p = ctypes.POINTER(ctypes.c_size_t)
# Make libnetsnmpagent available via Python's ctypes module. We do this globally
# so we can define C function prototypes
# Workaround for net-snmp 5.4.x that has a bug with unresolved dependencies
# in its libraries (http://sf.net/p/net-snmp/bugs/2107): load netsnmphelpers
# first
try:
libnsh = ctypes.cdll.LoadLibrary(ctypes.util.find_library("netsnmphelpers"))
except:
raise Exception("Could not load libnetsnmphelpers! Is net-snmp installed?")
try:
libnsa = ctypes.cdll.LoadLibrary(ctypes.util.find_library("netsnmpagent"))
except:
raise Exception("Could not load libnetsnmpagent! Is net-snmp installed?")
# net-snmp <5.6.x had various functions in libnetsnmphelpers.so that were moved
# to libnetsnmpagent.so in later versions. Use netsnmp_create_watcher_info as
# a test and define a libnsX handle to abstract from the actually used library
# version.
try:
libnsa.netsnmp_create_watcher_info
libnsX = libnsa
except AttributeError:
libnsX = libnsh
# include/net-snmp/library/callback.h
# Callback major types
SNMP_CALLBACK_LIBRARY = 0
SNMP_CALLBACK_APPLICATION = 1
# SNMP_CALLBACK_LIBRARY minor types
SNMP_CALLBACK_LOGGING = 4
SNMPCallback = ctypes.CFUNCTYPE(
ctypes.c_int, # result type
ctypes.c_int, # int majorID
ctypes.c_int, # int minorID
ctypes.c_void_p, # void *serverarg
ctypes.c_void_p # void *clientarg
)
for f in [ libnsa.snmp_register_callback ]:
f.argtypes = [
ctypes.c_int, # int major
ctypes.c_int, # int minor
SNMPCallback, # SNMPCallback *new_callback
ctypes.c_void_p # void *arg
]
f.restype = int
# include/net-snmp/agent/agent_callbacks.h
SNMPD_CALLBACK_INDEX_STOP = 11
# include/net-snmp/library/snmp_logging.h
LOG_EMERG = 0 # system is unusable
LOG_ALERT = 1 # action must be taken immediately
LOG_CRIT = 2 # critical conditions
LOG_ERR = 3 # error conditions
LOG_WARNING = 4 # warning conditions
LOG_NOTICE = 5 # normal but significant condition
LOG_INFO = 6 # informational
LOG_DEBUG = 7 # debug-level messages
class snmp_log_message(ctypes.Structure): pass
snmp_log_message_p = ctypes.POINTER(snmp_log_message)
snmp_log_message._fields_ = [
("priority", ctypes.c_int),
("msg", ctypes.c_char_p)
]
# include/net-snmp/library/snmp_api.h
SNMPERR_SUCCESS = 0
# include/net-snmp/library/default_store.h
NETSNMP_DS_LIBRARY_ID = 0
NETSNMP_DS_APPLICATION_ID = 1
NETSNMP_DS_LIB_PERSISTENT_DIR = 8
for f in [ libnsa.netsnmp_ds_set_boolean ]:
f.argtypes = [
ctypes.c_int, # int storeid
ctypes.c_int, # int which
ctypes.c_int # int value
]
f.restype = ctypes.c_int
for f in [ libnsa.netsnmp_ds_set_string ]:
f.argtypes = [
ctypes.c_int, # int storeid
ctypes.c_int, # int which
ctypes.c_char_p # const char *value
]
f.restype = ctypes.c_int
# include/net-snmp/agent/ds_agent.h
NETSNMP_DS_AGENT_ROLE = 1
NETSNMP_DS_AGENT_X_SOCKET = 1
# include/net-snmp/library/snmp.h
SNMP_ERR_NOERROR = 0
for f in [ libnsa.init_snmp ]:
f.argtypes = [
ctypes.c_char_p # const char *type
]
f.restype = None
for f in [ libnsa.snmp_shutdown ]:
f.argtypes = [
ctypes.c_char_p # const char *type
]
f.restype = None
# include/net-snmp/library/oid.h
c_oid = ctypes.c_ulong
c_oid_p = ctypes.POINTER(c_oid)
# include/net-snmp/types.h
MAX_OID_LEN = 128
# include/net-snmp/agent/snmp_vars.h
for f in [ libnsa.init_agent ]:
f.argtypes = [
ctypes.c_char_p # const char *app
]
f.restype = ctypes.c_int
for f in [ libnsa.shutdown_agent ]:
f.argtypes = None
f.restype = ctypes.c_int
# include/net-snmp/library/parse.h
class tree(ctypes.Structure): pass
# include/net-snmp/mib_api.h
for f in [ libnsa.netsnmp_init_mib ]:
f.argtypes = None
f.restype = None
for f in [ libnsa.read_mib ]:
f.argtypes = [
ctypes.c_char_p # const char *filename
]
f.restype = ctypes.POINTER(tree)
for f in [ libnsa.read_objid ]:
f.argtypes = [
ctypes.c_char_p, # const char *input
c_oid_p, # oid *output
c_sizet_p # size_t *out_len
]
f.restype = ctypes.c_int
# include/net-snmp/agent/agent_handler.h
HANDLER_CAN_GETANDGETNEXT = 0x01
HANDLER_CAN_SET = 0x02
HANDLER_CAN_RONLY = HANDLER_CAN_GETANDGETNEXT
HANDLER_CAN_RWRITE = (HANDLER_CAN_GETANDGETNEXT | \
HANDLER_CAN_SET)
class netsnmp_mib_handler(ctypes.Structure): pass
netsnmp_mib_handler_p = ctypes.POINTER(netsnmp_mib_handler)
class netsnmp_handler_registration(ctypes.Structure): pass
netsnmp_handler_registration_p = ctypes.POINTER(netsnmp_handler_registration)
netsnmp_handler_registration._fields_ = [
("handlerName", ctypes.c_char_p),
("contextName", ctypes.c_char_p),
("rootoid", c_oid_p),
("rootoid_len", ctypes.c_size_t),
("handler", netsnmp_mib_handler_p),
("modes", ctypes.c_int),
("priority", ctypes.c_int),
("range_subid", ctypes.c_int),
("range_ubound", c_oid),
("timeout", ctypes.c_int),
("global_cacheid", ctypes.c_int),
("my_reg_void", ctypes.c_void_p)
]
for f in [ libnsa.netsnmp_create_handler_registration ]:
f.argtypes = [
ctypes.c_char_p, # const char *name
ctypes.c_void_p, # Netsnmp_Node_Handler *handler_access_method
c_oid_p, # const oid *reg_oid
ctypes.c_size_t, # size_t reg_oid_len
ctypes.c_int # int modes
]
f.restype = netsnmp_handler_registration_p
# include/net-snmp/library/asn1.h
ASN_INTEGER = 0x02
ASN_OCTET_STR = 0x04
ASN_APPLICATION = 0x40
# counter64 requires some extra work because it can't be reliably represented
# by a single C data type
class counter64(ctypes.Structure):
@property
def value(self):
return self.high << 32 | self.low
@value.setter
def value(self, val):
self.high = val >> 32
self.low = val & 0xFFFFFFFF
def __init__(self, initval=0):
ctypes.Structure.__init__(self, 0, 0)
self.value = initval
counter64_p = ctypes.POINTER(counter64)
counter64._fields_ = [
("high", ctypes.c_ulong),
("low", ctypes.c_ulong)
]
# include/net-snmp/library/snmp_impl.h
ASN_IPADDRESS = ASN_APPLICATION | 0
ASN_COUNTER = ASN_APPLICATION | 1
ASN_UNSIGNED = ASN_APPLICATION | 2
ASN_TIMETICKS = ASN_APPLICATION | 3
ASN_COUNTER64 = ASN_APPLICATION | 6
# include/net-snmp/agent/watcher.h
WATCHER_FIXED_SIZE = 0x01
WATCHER_MAX_SIZE = 0x02
class netsnmp_watcher_info(ctypes.Structure): pass
netsnmp_watcher_info_p = ctypes.POINTER(netsnmp_watcher_info)
netsnmp_watcher_info._fields_ = [
("data", ctypes.c_void_p),
("data_size", ctypes.c_size_t),
("max_size", ctypes.c_size_t),
("type", ctypes.c_ubyte),
("flags", ctypes.c_int)
# net-snmp 5.7.x knows data_size_p here as well but we ignore it for
# backwards compatibility with net-snmp 5.4.x.
]
for f in [ libnsX.netsnmp_create_watcher_info ]:
f.argtypes = [
ctypes.c_void_p, # void *data
ctypes.c_size_t, # size_t size
ctypes.c_ubyte, # u_char type
ctypes.c_int # int flags
]
f.restype = netsnmp_watcher_info_p
for f in [ libnsX.netsnmp_register_watched_instance ]:
f.argtypes = [
netsnmp_handler_registration_p, # netsnmp_handler_registration *reginfo
netsnmp_watcher_info_p # netsnmp_watcher_info *winfo
]
f.restype = ctypes.c_int
for f in [ libnsX.netsnmp_register_watched_scalar ]:
f.argtypes = [
netsnmp_handler_registration_p, # netsnmp_handler_registration *reginfo
netsnmp_watcher_info_p # netsnmp_watcher_info *winfo
]
f.restype = ctypes.c_int
# include/net-snmp/types.h
class netsnmp_variable_list(ctypes.Structure): pass
netsnmp_variable_list_p = ctypes.POINTER(netsnmp_variable_list)
netsnmp_variable_list_p_p = ctypes.POINTER(netsnmp_variable_list_p)
# include/net-snmp/varbind_api.h
for f in [ libnsa.snmp_varlist_add_variable ]:
f.argtypes = [
netsnmp_variable_list_p_p, # netsnmp_variable_list **varlist
c_oid_p, # const oid *name
ctypes.c_size_t, # size_t name_length
ctypes.c_ubyte, # u_char type
ctypes.c_void_p, # const void *value
ctypes.c_size_t # size_t len
]
f.restype = netsnmp_variable_list_p
# include/net-snmp/agent/table_data.h
class netsnmp_table_row(ctypes.Structure): pass
netsnmp_table_row_p = ctypes.POINTER(netsnmp_table_row)
netsnmp_table_row._fields_ = [
("indexes", netsnmp_variable_list_p),
("index_oid", c_oid_p),
("index_oid_len", ctypes.c_size_t),
("data", ctypes.c_void_p),
("next", netsnmp_table_row_p),
("prev", netsnmp_table_row_p)
]
class netsnmp_table_data(ctypes.Structure): pass
netsnmp_table_data_p = ctypes.POINTER(netsnmp_table_data)
netsnmp_table_data._fields_ = [
("indexes_template", netsnmp_variable_list_p),
("name", ctypes.c_char_p),
("flags", ctypes.c_int),
("store_indexes", ctypes.c_int),
("first_row", netsnmp_table_row_p),
("last_row", netsnmp_table_row_p)
]
# include/net-snmp/agent/table_dataset.h
class netsnmp_table_data_set_storage_udata(ctypes.Union): pass
netsnmp_table_data_set_storage_udata._fields_ = [
("voidp", ctypes.c_void_p),
("integer", ctypes.POINTER(ctypes.c_long)),
("string", ctypes.c_char_p),
("objid", c_oid_p),
("bitstring", ctypes.POINTER(ctypes.c_ubyte)),
("counter64", ctypes.POINTER(counter64)),
("floatVal", ctypes.POINTER(ctypes.c_float)),
("doubleVal", ctypes.POINTER(ctypes.c_double))
]
class netsnmp_table_data_set_storage(ctypes.Structure): pass
netsnmp_table_data_set_storage_p = ctypes.POINTER(netsnmp_table_data_set_storage)
netsnmp_table_data_set_storage._fields_ = [
("column", ctypes.c_uint),
("writable", ctypes.c_byte),
("change_ok_fn", ctypes.c_void_p),
("my_change_data", ctypes.c_void_p),
("type", ctypes.c_ubyte),
("data", netsnmp_table_data_set_storage_udata),
("data_len", ctypes.c_ulong),
("next", netsnmp_table_data_set_storage_p)
]
class netsnmp_table_data_set(ctypes.Structure): pass
netsnmp_table_data_set_p = ctypes.POINTER(netsnmp_table_data_set)
netsnmp_table_data_set._fields_ = [
("table", netsnmp_table_data_p),
("default_row", netsnmp_table_data_set_storage_p),
("allow_creation", ctypes.c_int),
("rowstatus_column", ctypes.c_uint)
]
for f in [ libnsX.netsnmp_create_table_data_set ]:
f.argtypes = [
ctypes.c_char_p # const char *table_name
]
f.restype = netsnmp_table_data_set_p
for f in [ libnsX.netsnmp_table_dataset_add_row ]:
f.argtypes = [
netsnmp_table_data_set_p, # netsnmp_table_data_set *table
netsnmp_table_row_p, # netsnmp_table_row *row
]
f.restype = None
for f in [ libnsX.netsnmp_table_data_set_create_row_from_defaults ]:
f.argtypes = [
netsnmp_table_data_set_storage_p # netsnmp_table_data_set_storage *defrow
]
f.restype = netsnmp_table_row_p
for f in [ libnsX.netsnmp_table_set_add_default_row ]:
f.argtypes = [
netsnmp_table_data_set_p, # netsnmp_table_data_set *table_set
ctypes.c_uint, # unsigned int column
ctypes.c_int, # int type
ctypes.c_int, # int writable
ctypes.c_void_p, # void *default_value
ctypes.c_size_t # size_t default_value_len
]
f.restype = ctypes.c_int
for f in [ libnsX.netsnmp_register_table_data_set ]:
f.argtypes = [
netsnmp_handler_registration_p, # netsnmp_handler_registration *reginfo
netsnmp_table_data_set_p, # netsnmp_table_data_set *data_set
ctypes.c_void_p # netsnmp_table_registration_info *table_info
]
f.restype = ctypes.c_int
for f in [ libnsX.netsnmp_set_row_column ]:
f.argtypes = [
netsnmp_table_row_p, # netsnmp_table_row *row
ctypes.c_uint, # unsigned int column
ctypes.c_int, # int type
ctypes.c_void_p, # const void *value
ctypes.c_size_t # size_t value_len
]
f.restype = ctypes.c_int
for f in [ libnsX.netsnmp_table_dataset_add_index ]:
f.argtypes = [
netsnmp_table_data_set_p, # netsnmp_table_data_set *table
ctypes.c_ubyte # u_char type
]
f.restype = None
for f in [ libnsX.netsnmp_table_dataset_remove_and_delete_row ]:
f.argtypes = [
netsnmp_table_data_set_p, # netsnmp_table_data_set *table
netsnmp_table_row_p # netsnmp_table_row *row
]
# include/net-snmp/agent/snmp_agent.h
for f in [ libnsa.agent_check_and_process ]:
f.argtypes = [
ctypes.c_int # int block
]
f.restype = ctypes.c_int
|
