-"""
- Interface to OpenSSL object identifier database
"""
-from ctypescrypto import libcrypto
-class Oid:
- def __init__(self,value):
- if type(value) == type(""):
- self.nid=libcrypto.OBJ_txt2nid(value)
- if self.nid==0:
- raise LibCryptoError("Cannot find object %s in the
- database"%(value))
- elif type(value) == type(0):
- self.nid=value
- else:
- raise TypeError("Cannot convert this type to object identifier")
- def __cmp__(self,other):
- return self.nid-other.nid
- def __str__(self):
- return self.dotted()
- def shorttname(self):
- return libcrypto.OBJ_nid2sn(self.nid)
- def longname(self):
- return libcrypto.OBJ_nid2ln(self.nid)
- def dotted(self)
- obj=libcrypto.OBJ_nid2obj(self.nid)
- buf=create_string_buffer(256)
- libcrypto.OBJ_obj2txt(buf,256,obj,1)
- return buf.value
+Interface to OpenSSL object identifier database.
+It is primarily intended to deal with OIDs which are compiled into the
+database or defined in the openssl configuration files.
+
+But see create() function.
+
+OpenSSL maintains database of OIDs, which contain long and short
+human-readable names, which correspond to Oid as well as canonical
+dotted-decimal representation, and links it to small integer, named
+numeric identifier or 'nid'. Most OpenSSL functions which deals with
+ASN.1 structures such as certificates or cryptographic messages,
+expect or return nids, but it is very bad idea to hardcode nids into
+your app, because it can change after mere recompilation of OpenSSL
+library.
+
+This module provides Oid object which represents entry to OpenSSL
+OID database.
+"""
+from ctypescrypto import libcrypto, pyver,bintype,chartype,inttype
+from ctypes import c_char_p, c_void_p, c_int, create_string_buffer
+from ctypescrypto.exception import LibCryptoError
+
+__all__ = ['Oid', 'create', 'cleanup']
+
+class Oid(object):
+ """
+ Represents an OID (ASN.1 Object identifier).
+
+
+ It can be consturucted by textual
+ representation like Oid("commonName") or Oid("CN"),
+ dotted-decimal Oid("1.2.3.4") or using OpenSSL numeric
+ identifer (NID), which is typically returned or required by
+ OpenSSL API functions. If object is consturcted from textual
+ representation which is not present in the database, it fails
+ with ValueError
+
+ attribute nid - contains object nid.
+ """
+
+ def __init__(self, value):
+ """
+ Object constructor. Accepts string, integer, or another Oid
+ object.
+
+ Integer should be OpenSSL numeric identifier (nid) as returned
+ by some libcrypto function or extracted from some libcrypto
+ structure
+ """
+ if isinstance(value, chartype):
+ value = value.encode('ascii')
+ if isinstance(value, bintype):
+ self.nid = libcrypto.OBJ_txt2nid(value)
+ if self.nid == 0:
+ raise ValueError("Cannot find object %s in the database" %
+ value)
+ elif isinstance(value, inttype):
+ short = libcrypto.OBJ_nid2sn(value)
+ if short is None:
+ raise ValueError("No such nid %d in the database" % value)
+ self.nid = value
+ elif isinstance(value, Oid):
+ self.nid = value.nid
+ else:
+ raise TypeError("Cannot convert this type to object identifier")
+ def __hash__(self):
+ " Hash of object is equal to nid because Oids with same nid are same"
+ return self.nid
+ def __eq__ (self, other):
+ return self.nid == other.nid
+ def __hash__(self):
+ """ Returns NID of object as hash value. Should make Oids with
+ identical NID compare equal and also let use Oids as
+ dictionary keys"""
+ return self.nid
+ def __str__(self):
+ " Default string representation of Oid is dotted-decimal "
+ return self.dotted()
+ def __repr__(self):
+ " Returns constructor call of Oid with dotted representation "
+ return "Oid('%s')" % (self.dotted())
+ if pyver == 2:
+ def shortname(self):
+ " Returns short name if any "
+ return libcrypto.OBJ_nid2sn(self.nid)
+ def longname(self):
+ " Returns long name if any "
+ return libcrypto.OBJ_nid2ln(self.nid)
+ else:
+ def shortname(self):
+ " Returns short name if any "
+ return libcrypto.OBJ_nid2sn(self.nid).decode('utf-8')
+ def longname(self):
+ " Returns long name if any "
+ return libcrypto.OBJ_nid2ln(self.nid).decode('utf-8')
+
+ def dotted(self):
+ " Returns dotted-decimal reperesentation "
+ obj = libcrypto.OBJ_nid2obj(self.nid)
+ buf = create_string_buffer(256)
+ libcrypto.OBJ_obj2txt(buf, 256, obj, 1)
+ if pyver == 2:
+ return buf.value
+ else:
+ return buf.value.decode('ascii')
+ @staticmethod
+ def fromobj(obj):
+ """
+ Creates an OID object from the pointer to ASN1_OBJECT c structure.
+ This method intended for internal use for submodules which deal
+ with libcrypto ASN1 parsing functions, such as x509 or CMS
+ """
+ nid = libcrypto.OBJ_obj2nid(obj)
+ if nid == 0:
+ buf = create_string_buffer(80)
+ dotted_len = libcrypto.OBJ_obj2txt(buf, 80, obj, 1)
+ dotted = buf[:dotted_len]
+ oid = create(dotted, dotted, dotted)
+ else:
+ oid = Oid(nid)
+ return oid
+
+def create(dotted, shortname, longname):
+ """
+ Creates new OID in the database
+
+ @param dotted - dotted-decimal representation of new OID
+ @param shortname - short name for new OID
+ @param longname - long name for new OID
+
+ @returns Oid object corresponding to new OID
+
+ This function should be used with exreme care. Whenever
+ possible, it is better to add new OIDs via OpenSSL configuration
+ file
+
+ Results of calling this function twice for same OIDor for
+ Oid alredy in database are undefined
+
+ """
+ if pyver > 2:
+ dotted = dotted.encode('ascii')
+ shortname = shortname.encode('utf-8')
+ longname = longname.encode('utf-8')
+ nid = libcrypto.OBJ_create(dotted, shortname, longname)
+ if nid == 0:
+ raise LibCryptoError("Problem adding new OID to the database")
+ return Oid(nid)
+
+def cleanup():
+ """
+ Removes all the objects, dynamically added by current
+ application from database.
+
+ Note that in OpenSSL 1.1.0 and above OBJ_cleanup really does nothing
+ """
+ if hasattr(libcrypto,"OBJ_cleanup"):
+ libcrypto.OBJ_cleanup()
+
+libcrypto.OBJ_nid2sn.restype = c_char_p
+libcrypto.OBJ_nid2ln.restype = c_char_p
+libcrypto.OBJ_nid2obj.restype = c_void_p
+libcrypto.OBJ_obj2nid.restype = c_int
+libcrypto.OBJ_obj2txt.argtypes = (c_char_p, c_int, c_void_p, c_int)
+libcrypto.OBJ_txt2nid.argtupes = (c_char_p, )
+libcrypto.OBJ_obj2nid.argtupes = (c_void_p, )
+libcrypto.OBJ_create.argtypes = (c_char_p, c_char_p, c_char_p)
projects / oss / ctypescrypto.git / blobdiff