schema.py

from struct import Struct
from datetime import datetime

# http://web.mit.edu/darwin/src/modules/Security/cdsa/cdsa/cssmtype.h
KEY_TYPE = {
    0x00 + 0x0F: 'CSSM_KEYCLASS_PUBLIC_KEY',
    0x01 + 0x0F: 'CSSM_KEYCLASS_PRIVATE_KEY',
    0x02 + 0x0F: 'CSSM_KEYCLASS_SESSION_KEY',
    0x03 + 0x0F: 'CSSM_KEYCLASS_SECRET_PART',
    0xFFFFFFFF: 'CSSM_KEYCLASS_OTHER'
}

CSSM_ALGORITHMS = {
    0: 'CSSM_ALGID_NONE',
    1: 'CSSM_ALGID_CUSTOM',
    2: 'CSSM_ALGID_DH',
    3: 'CSSM_ALGID_PH',
    4: 'CSSM_ALGID_KEA',
    5: 'CSSM_ALGID_MD2',
    6: 'CSSM_ALGID_MD4',
    7: 'CSSM_ALGID_MD5',
    8: 'CSSM_ALGID_SHA1',
    9: 'CSSM_ALGID_NHASH',
    10: 'CSSM_ALGID_HAVAL:',
    11: 'CSSM_ALGID_RIPEMD',
    12: 'CSSM_ALGID_IBCHASH',
    13: 'CSSM_ALGID_RIPEMAC',
    14: 'CSSM_ALGID_DES',
    15: 'CSSM_ALGID_DESX',
    16: 'CSSM_ALGID_RDES',
    17: 'CSSM_ALGID_3DES_3KEY_EDE',
    18: 'CSSM_ALGID_3DES_2KEY_EDE',
    19: 'CSSM_ALGID_3DES_1KEY_EEE',
    20: 'CSSM_ALGID_3DES_3KEY_EEE',
    21: 'CSSM_ALGID_3DES_2KEY_EEE',
    22: 'CSSM_ALGID_IDEA',
    23: 'CSSM_ALGID_RC2',
    24: 'CSSM_ALGID_RC5',
    25: 'CSSM_ALGID_RC4',
    26: 'CSSM_ALGID_SEAL',
    27: 'CSSM_ALGID_CAST',
    28: 'CSSM_ALGID_BLOWFISH',
    29: 'CSSM_ALGID_SKIPJACK',
    30: 'CSSM_ALGID_LUCIFER',
    31: 'CSSM_ALGID_MADRYGA',
    32: 'CSSM_ALGID_FEAL',
    33: 'CSSM_ALGID_REDOC',
    34: 'CSSM_ALGID_REDOC3',
    35: 'CSSM_ALGID_LOKI',
    36: 'CSSM_ALGID_KHUFU',
    37: 'CSSM_ALGID_KHAFRE',
    38: 'CSSM_ALGID_MMB',
    39: 'CSSM_ALGID_GOST',
    40: 'CSSM_ALGID_SAFER',
    41: 'CSSM_ALGID_CRAB',
    42: 'CSSM_ALGID_RSA',
    43: 'CSSM_ALGID_DSA',
    44: 'CSSM_ALGID_MD5WithRSA',
    45: 'CSSM_ALGID_MD2WithRSA',
    46: 'CSSM_ALGID_ElGamal',
    47: 'CSSM_ALGID_MD2Random',
    48: 'CSSM_ALGID_MD5Random',
    49: 'CSSM_ALGID_SHARandom',
    50: 'CSSM_ALGID_DESRandom',
    51: 'CSSM_ALGID_SHA1WithRSA',
    52: 'CSSM_ALGID_CDMF',
    53: 'CSSM_ALGID_CAST3',
    54: 'CSSM_ALGID_CAST5',
    55: 'CSSM_ALGID_GenericSecret',
    56: 'CSSM_ALGID_ConcatBaseAndKey',
    57: 'CSSM_ALGID_ConcatKeyAndBase',
    58: 'CSSM_ALGID_ConcatBaseAndData',
    59: 'CSSM_ALGID_ConcatDataAndBase',
    60: 'CSSM_ALGID_XORBaseAndData',
    61: 'CSSM_ALGID_ExtractFromKey',
    62: 'CSSM_ALGID_SSL3PreMasterGen',
    63: 'CSSM_ALGID_SSL3MasterDerive',
    64: 'CSSM_ALGID_SSL3KeyAndMacDerive',
    65: 'CSSM_ALGID_SSL3MD5_MAC',
    66: 'CSSM_ALGID_SSL3SHA1_MAC',
    67: 'CSSM_ALGID_PKCS5_PBKDF1_MD5',
    68: 'CSSM_ALGID_PKCS5_PBKDF1_MD2',
    69: 'CSSM_ALGID_PKCS5_PBKDF1_SHA1',
    70: 'CSSM_ALGID_WrapLynks',
    71: 'CSSM_ALGID_WrapSET_OAEP',
    72: 'CSSM_ALGID_BATON',
    73: 'CSSM_ALGID_ECDSA',
    74: 'CSSM_ALGID_MAYFLY',
    75: 'CSSM_ALGID_JUNIPER',
    76: 'CSSM_ALGID_FASTHASH',
    77: 'CSSM_ALGID_3DES',
    78: 'CSSM_ALGID_SSL3MD5',
    79: 'CSSM_ALGID_SSL3SHA1',
    80: 'CSSM_ALGID_FortezzaTimestamp',
    81: 'CSSM_ALGID_SHA1WithDSA',
    82: 'CSSM_ALGID_SHA1WithECDSA',
    83: 'CSSM_ALGID_DSA_BSAFE',
    84: 'CSSM_ALGID_ECDH',
    85: 'CSSM_ALGID_ECMQV',
    86: 'CSSM_ALGID_PKCS12_SHA1_PBE',
    87: 'CSSM_ALGID_ECNRA',
    88: 'CSSM_ALGID_SHA1WithECNRA',
    89: 'CSSM_ALGID_ECES',
    90: 'CSSM_ALGID_ECAES',
    91: 'CSSM_ALGID_SHA1HMAC',
    92: 'CSSM_ALGID_FIPS186Random',
    93: 'CSSM_ALGID_ECC',
    94: 'CSSM_ALGID_MQV',
    95: 'CSSM_ALGID_NRA',
    96: 'CSSM_ALGID_IntelPlatformRandom',
    97: 'CSSM_ALGID_UTC',
    98: 'CSSM_ALGID_HAVAL3',
    99: 'CSSM_ALGID_HAVAL4',
    100: 'CSSM_ALGID_HAVAL5',
    101: 'CSSM_ALGID_TIGER',
    102: 'CSSM_ALGID_MD5HMAC',
    103: 'CSSM_ALGID_PKCS5_PBKDF2',
    104: 'CSSM_ALGID_RUNNING_COUNTER',
    0x7FFFFFFF: 'CSSM_ALGID_LAST'
}

# CSSM TYPE
## http://www.opensource.apple.com/source/libsecurity_cssm/libsecurity_cssm-36064/lib/cssmtype.h

########## CSSM_DB_RECORDTYPE #############

# /* Industry At Large Application Name Space Range Definition */
# /* AppleFileDL record types. */
CSSM_DB_RECORDTYPE_APP_DEFINED_START = 0x80000000
CSSM_DL_DB_RECORD_GENERIC_PASSWORD = CSSM_DB_RECORDTYPE_APP_DEFINED_START + 0
CSSM_DL_DB_RECORD_INTERNET_PASSWORD = CSSM_DB_RECORDTYPE_APP_DEFINED_START + 1
CSSM_DL_DB_RECORD_APPLESHARE_PASSWORD = CSSM_DB_RECORDTYPE_APP_DEFINED_START + 2
CSSM_DL_DB_RECORD_USER_TRUST = CSSM_DB_RECORDTYPE_APP_DEFINED_START + 3
CSSM_DL_DB_RECORD_X509_CRL = CSSM_DB_RECORDTYPE_APP_DEFINED_START + 4
CSSM_DL_DB_RECORD_UNLOCK_REFERRAL = CSSM_DB_RECORDTYPE_APP_DEFINED_START + 5
CSSM_DL_DB_RECORD_EXTENDED_ATTRIBUTE = CSSM_DB_RECORDTYPE_APP_DEFINED_START + 6

CSSM_DL_DB_RECORD_X509_CERTIFICATE = CSSM_DB_RECORDTYPE_APP_DEFINED_START + 0x1000
CSSM_DL_DB_RECORD_METADATA = CSSM_DB_RECORDTYPE_APP_DEFINED_START + 0x8000  ## DBBlob
CSSM_DB_RECORDTYPE_APP_DEFINED_END = 0xffffffff

# /* Record Types defined in the Schema Management Name Space */
CSSM_DB_RECORDTYPE_SCHEMA_START = 0x00000000
CSSM_DL_DB_SCHEMA_INFO = CSSM_DB_RECORDTYPE_SCHEMA_START + 0
CSSM_DL_DB_SCHEMA_INDEXES = CSSM_DB_RECORDTYPE_SCHEMA_START + 1
CSSM_DL_DB_SCHEMA_ATTRIBUTES = CSSM_DB_RECORDTYPE_SCHEMA_START + 2
CSSM_DL_DB_SCHEMA_PARSING_MODULE = CSSM_DB_RECORDTYPE_SCHEMA_START + 3
CSSM_DB_RECORDTYPE_SCHEMA_END = CSSM_DB_RECORDTYPE_SCHEMA_START + 4

# /* Record Types defined in the Open Group Application Name Space */
# /* Open Group Application Name Space Range Definition*/
CSSM_DB_RECORDTYPE_OPEN_GROUP_START = 0x0000000A
CSSM_DL_DB_RECORD_ANY = CSSM_DB_RECORDTYPE_OPEN_GROUP_START + 0
CSSM_DL_DB_RECORD_CERT = CSSM_DB_RECORDTYPE_OPEN_GROUP_START + 1
CSSM_DL_DB_RECORD_CRL = CSSM_DB_RECORDTYPE_OPEN_GROUP_START + 2
CSSM_DL_DB_RECORD_POLICY = CSSM_DB_RECORDTYPE_OPEN_GROUP_START + 3
CSSM_DL_DB_RECORD_GENERIC = CSSM_DB_RECORDTYPE_OPEN_GROUP_START + 4
CSSM_DL_DB_RECORD_PUBLIC_KEY = CSSM_DB_RECORDTYPE_OPEN_GROUP_START + 5
CSSM_DL_DB_RECORD_PRIVATE_KEY = CSSM_DB_RECORDTYPE_OPEN_GROUP_START + 6
CSSM_DL_DB_RECORD_SYMMETRIC_KEY = CSSM_DB_RECORDTYPE_OPEN_GROUP_START + 7
CSSM_DL_DB_RECORD_ALL_KEYS = CSSM_DB_RECORDTYPE_OPEN_GROUP_START + 8
CSSM_DB_RECORDTYPE_OPEN_GROUP_END = CSSM_DB_RECORDTYPE_OPEN_GROUP_START + 8
#####################

######## KEYUSE #########
CSSM_KEYUSE_ANY = 0x80000000
CSSM_KEYUSE_ENCRYPT = 0x00000001
CSSM_KEYUSE_DECRYPT = 0x00000002
CSSM_KEYUSE_SIGN = 0x00000004
CSSM_KEYUSE_VERIFY = 0x00000008
CSSM_KEYUSE_SIGN_RECOVER = 0x00000010
CSSM_KEYUSE_VERIFY_RECOVER = 0x00000020
CSSM_KEYUSE_WRAP = 0x00000040
CSSM_KEYUSE_UNWRAP = 0x00000080
CSSM_KEYUSE_DERIVE = 0x00000100
####################

############ CERT TYPE ##############
CERT_TYPE = {
    0x00: 'CSSM_CERT_UNKNOWN',
    0x01: 'CSSM_CERT_X_509v1',
    0x02: 'CSSM_CERT_X_509v2',
    0x03: 'CSSM_CERT_X_509v3',
    0x04: 'CSSM_CERT_PGP',
    0x05: 'CSSM_CERT_SPKI',
    0x06: 'CSSM_CERT_SDSIv1',
    0x08: 'CSSM_CERT_Intel',
    0x09: 'CSSM_CERT_X_509_ATTRIBUTE',
    0x0A: 'CSSM_CERT_X9_ATTRIBUTE',
    0x0C: 'CSSM_CERT_ACL_ENTRY',
    0x7FFE: 'CSSM_CERT_MULTIPLE',
    0x7FFF: 'CSSM_CERT_LAST',
    0x8000: 'CSSM_CL_CUSTOM_CERT_TYPE'
}
####################################

########### CERT ENCODING #############
CERT_ENCODING = {
    0x00: 'CSSM_CERT_ENCODING_UNKNOWN',
    0x01: 'CSSM_CERT_ENCODING_CUSTOM',
    0x02: 'CSSM_CERT_ENCODING_BER',
    0x03: 'CSSM_CERT_ENCODING_DER',
    0x04: 'CSSM_CERT_ENCODING_NDR',
    0x05: 'CSSM_CERT_ENCODING_SEXPR',
    0x06: 'CSSM_CERT_ENCODING_PGP',
    0x7FFE: 'CSSM_CERT_ENCODING_MULTIPLE',
    0x7FFF: 'CSSM_CERT_ENCODING_LAST'
}

STD_APPLE_ADDIN_MODULE = {
    '{87191ca0-0fc9-11d4-849a-000502b52122}': 'CSSM itself',
    '{87191ca1-0fc9-11d4-849a-000502b52122}': 'File based DL (aka "Keychain DL")',
    '{87191ca2-0fc9-11d4-849a-000502b52122}': 'Core CSP (local space)',
    '{87191ca3-0fc9-11d4-849a-000502b52122}': 'Secure CSP/DL (aka "Keychain CSPDL")',
    '{87191ca4-0fc9-11d4-849a-000502b52122}': 'X509 Certificate CL',
    '{87191ca5-0fc9-11d4-849a-000502b52122}': 'X509 Certificate TP',
    '{87191ca6-0fc9-11d4-849a-000502b52122}': 'DLAP/OpenDirectory access DL',
    '{87191ca7-0fc9-11d4-849a-000502b52122}': 'TP for ".mac" related policies',
    '{87191ca8-0fc9-11d4-849a-000502b52122}': 'Smartcard CSP/DL',
    '{87191ca9-0fc9-11d4-849a-000502b52122}': 'DL for ".mac" certificate access'
}

SECURE_STORAGE_GROUP = 'ssgp'

# SecAuthenticationType
AUTH_TYPE = {
    'ntlm': 'kSecAuthenticationTypeNTLM',
    'msna': 'kSecAuthenticationTypeMSN',
    'dpaa': 'kSecAuthenticationTypeDPA',
    'rpaa': 'kSecAuthenticationTypeRPA',
    'http': 'kSecAuthenticationTypeHTTPBasic',
    'httd': 'kSecAuthenticationTypeHTTPDigest',
    'form': 'kSecAuthenticationTypeHTMLForm',
    'dflt': 'kSecAuthenticationTypeDefault',
    '': 'kSecAuthenticationTypeAny',
    '\x00\x00\x00\x00': 'kSecAuthenticationTypeAny'
}

# SecProtocolType
PROTOCOL_TYPE = {
    'ftp ': 'kSecProtocolTypeFTP',
    'ftpa': 'kSecProtocolTypeFTPAccount',
    'http': 'kSecProtocolTypeHTTP',
    'irc ': 'kSecProtocolTypeIRC',
    'nntp': 'kSecProtocolTypeNNTP',
    'pop3': 'kSecProtocolTypePOP3',
    'smtp': 'kSecProtocolTypeSMTP',
    'sox ': 'kSecProtocolTypeSOCKS',
    'imap': 'kSecProtocolTypeIMAP',
    'ldap': 'kSecProtocolTypeLDAP',
    'atlk': 'kSecProtocolTypeAppleTalk',
    'afp ': 'kSecProtocolTypeAFP',
    'teln': 'kSecProtocolTypeTelnet',
    'ssh ': 'kSecProtocolTypeSSH',
    'ftps': 'kSecProtocolTypeFTPS',
    'htps': 'kSecProtocolTypeHTTPS',
    'htpx': 'kSecProtocolTypeHTTPProxy',
    'htsx': 'kSecProtocolTypeHTTPSProxy',
    'ftpx': 'kSecProtocolTypeFTPProxy',
    'cifs': 'kSecProtocolTypeCIFS',
    'smb ': 'kSecProtocolTypeSMB',
    'rtsp': 'kSecProtocolTypeRTSP',
    'rtsx': 'kSecProtocolTypeRTSPProxy',
    'daap': 'kSecProtocolTypeDAAP',
    'eppc': 'kSecProtocolTypeEPPC',
    'ipp ': 'kSecProtocolTypeIPP',
    'ntps': 'kSecProtocolTypeNNTPS',
    'ldps': 'kSecProtocolTypeLDAPS',
    'tels': 'kSecProtocolTypeTelnetS',
    'imps': 'kSecProtocolTypeIMAPS',
    'ircs': 'kSecProtocolTypeIRCS',
    'pops': 'kSecProtocolTypePOP3S',
    'cvsp': 'kSecProtocolTypeCVSpserver',
    'svn ': 'kSecProtocolTypeCVSpserver',
    'AdIM': 'kSecProtocolTypeAdiumMessenger',
    '\x00\x00\x00\x00': 'kSecProtocolTypeAny'
}

# This is somewhat gross: we define a bunch of module-level constants based on
# the SecKeychainItem.h defines (FourCharCodes) by passing them through
# struct.unpack and converting them to ctypes.c_long() since we'll never use
# them for non-native APIs

CARBON_DEFINES = {
    'cdat': 'kSecCreationDateItemAttr',
    'mdat': 'kSecModDateItemAttr',
    'desc': 'kSecDescriptionItemAttr',
    'icmt': 'kSecCommentItemAttr',
    'crtr': 'kSecCreatorItemAttr',
    'type': 'kSecTypeItemAttr',
    'scrp': 'kSecScriptCodeItemAttr',
    'labl': 'kSecLabelItemAttr',
    'invi': 'kSecInvisibleItemAttr',
    'nega': 'kSecNegativeItemAttr',
    'cusi': 'kSecCustomIconItemAttr',
    'acct': 'kSecAccountItemAttr',
    'svce': 'kSecServiceItemAttr',
    'gena': 'kSecGenericItemAttr',
    'sdmn': 'kSecSecurityDomainItemAttr',
    'srvr': 'kSecServerItemAttr',
    'atyp': 'kSecAuthenticationTypeItemAttr',
    'port': 'kSecPortItemAttr',
    'path': 'kSecPathItemAttr',
    'vlme': 'kSecVolumeItemAttr',
    'addr': 'kSecAddressItemAttr',
    'ssig': 'kSecSignatureItemAttr',
    'ptcl': 'kSecProtocolItemAttr',
    'ctyp': 'kSecCertificateType',
    'cenc': 'kSecCertificateEncoding',
    'crtp': 'kSecCrlType',
    'crnc': 'kSecCrlEncoding',
    'alis': 'kSecAlias',
    'inet': 'kSecInternetPasswordItemClass',
    'genp': 'kSecGenericPasswordItemClass',
    'ashp': 'kSecAppleSharePasswordItemClass',
    CSSM_DL_DB_RECORD_X509_CERTIFICATE: 'kSecCertificateItemClass'
}

class _APPL_DB_HEADER(object):
    STRUCT = Struct('> 4s i i i i')

    def __init__(self, buffer):
        (self.Signature, self.Version, self.HeaderSize, self.SchemaOffset,
         self.AuthOffset) = _APPL_DB_HEADER.STRUCT.unpack(
            buffer)


class _APPL_DB_SCHEMA(object):
    STRUCT = Struct('> i i')

    def __init__(self, buffer):
        (self.SchemaSize, self.TableCount) = _APPL_DB_SCHEMA.STRUCT.unpack(buffer)


class _TABLE_HEADER(object):
    STRUCT = Struct('> I I I I I I I')

    def __init__(self, buffer):
        (self.TableSize, self.TableId, self.RecordCount, self.Records, self.IndexesOffset, self.FreeListHead,
         self.RecordNumbersCount) = _TABLE_HEADER.STRUCT.unpack(buffer)


class _DB_BLOB(object):
    STRUCT = Struct('> 8s I I 16s I 8s 20s 8s 20s')

    def __init__(self, buffer):
        (self.CommonBlobBuffer, self.StartCryptoBlob, self.TotalLength, self.RandomSignature, self.Sequence,
         self.ParamsBuffer, self.Salt, self.IV, self.BlobSignature) = _DB_BLOB.STRUCT.unpack(buffer)

        self.CommonBlob = _COMMON_BLOB(self.CommonBlobBuffer)
        self.Params = _DB_PARAMETERS(self.ParamsBuffer)


class _COMMON_BLOB(object):
    STRUCT = Struct('> L l')

    def __init__(self, buffer):
        (self.Magic, self.BlobVersion) = _COMMON_BLOB.STRUCT.unpack(buffer)


class _DB_PARAMETERS(object):
    STRUCT = Struct('> I I')
    def __init__(self, buffer):
        (self.IdleTimeout, self.LockOnSleep) = _DB_PARAMETERS.STRUCT.unpack(buffer)


class _GENERIC_PW_HEADER(object):
    STRUCT = Struct('> I I I I I I I I I I I I I I I I I I I I I I')

    def __init__(self, buffer):
        (self.RecordSize, self.RecordNumber, self.Unknown2, self.Unknown3, self.SSGPArea, self.Unknown5,
         self.CreationDate, self.ModDate, self.Description, self.Comment, self.Creator, self.Type, self.ScriptCode,
         self.PrintName, self.Alias, self.Invisible, self.Negative, self.CustomIcon, self.Protected, self.Account,
         self.Service, self.Generic,) = _GENERIC_PW_HEADER.STRUCT.unpack(buffer)


class _KEY_BLOB_REC_HEADER(object):
    STRUCT = Struct('> I I 124s ')

    def __init__(self, buffer):
        (self.RecordSize, self.RecordCount, self.Dummy) = _KEY_BLOB_REC_HEADER.STRUCT.unpack(buffer)


class _KEY_BLOB(object):
    STRUCT = Struct('> 8s I I 8s')
    COMMON_BLOB_MAGIC = 0xFADE0711

    def __init__(self, buffer):
        (self.CommonBlobBuffer, self.StartCryptoBlob, self.TotalLength, self.IV,) = _KEY_BLOB.STRUCT.unpack(buffer)

        self.CommonBlob = _COMMON_BLOB(self.CommonBlobBuffer)


# First 28 bytes are structured - remainder is our encrypted password.
class _SSGP(object):
    STRUCT = Struct('> 4s 16s 8s')

    def __init__(self, buffer):
        (self.Magic, self.Label, self.IV,) = _SSGP.STRUCT.unpack(buffer[:28])
        self.EncryptedPassword = buffer[28:]


class _INTERNET_PW_HEADER(object):
    STRUCT = Struct('> I I I I I I I I I I I I I I I I I I I I I I I I I I')

    def __init__(self, buffer):
        (self.RecordSize, self.RecordNumber, self.Unknown2, self.Unknown3, self.SSGPArea, self.Unknown5,
         self.CreationDate, self.ModDate, self.Description, self.Comment, self.Creator, self.Type, self.ScriptCode,
         self.PrintName, self.Alias, self.Invisible, self.Negative, self.CustomIcon, self.Protected, self.Account,
         self.SecurityDomain, self.Server, self.Protocol, self.AuthType, self.Port,
         self.Path,) = _INTERNET_PW_HEADER.STRUCT.unpack(buffer)


class _APPLE_SHARE_HEADER(object):
    STRUCT = Struct('> I I I I I I I I I I I I I I I I I I I I I I I I I I')

    def __init__(self, buffer):
        (self.RecordSize, self.RecordNumber, self.Unknown2, self.Unknown3, self.SSGPArea, self.Unknown5,
         self.CreationDate, self.ModDate, self.Description, self.Comment, self.Creator, self.Type, self.ScriptCode,
         self.PrintName, self.Alias, self.Invisible, self.Negative, self.CustomIcon, self.Protected, self.Account,
         self.Volume, self.Server, self.Protocol, self.AuthType, self.Address,
         self.Signature,) = _APPLE_SHARE_HEADER.STRUCT.unpack(buffer)


class _X509_CERT_HEADER(object):
    STRUCT = Struct('> I I I I I I I I I I I I I I I')

    def __init__(self, buffer):
        (self.RecordSize, self.RecordNumber, self.Unknown1, self.Unknown2, self.CertSize, self.Unknown3, self.CertType,
         self.CertEncoding, self.PrintName, self.Alias, self.Subject, self.Issuer, self.SerialNumber,
         self.SubjectKeyIdentifier, self.PublicKeyHash,) = _X509_CERT_HEADER.STRUCT.unpack(buffer)


# # http://www.opensource.apple.com/source/Security/Security-55179.1/include/security_cdsa_utilities/KeySchema.h
# # http://www.opensource.apple.com/source/libsecurity_keychain/libsecurity_keychain-36940/lib/SecKey.h

class _SECKEY_HEADER(object):
    STRUCT = Struct('> I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I')

    def __init__(self, buffer):
        (self.RecordSize, self.RecordNumber, self.Unknown1, self.Unknown2, self.BlobSize, self.Unknown3, self.KeyClass,
         self.PrintName, self.Alias, self.Permanent, self.Private, self.Modifiable, self.Label, self.ApplicationTag,
         self.KeyCreator, self.KeyType, self.KeySizeInBits, self.EffectiveKeySize, self.StartDate, self.EndDate,
         self.Sensitive, self.AlwaysSensitive, self.Extractable, self.NeverExtractable, self.Encrypt, self.Decrypt,
         self.Derive, self.Sign, self.Verify, self.SignRecover, self.VerifyRecover, self.Wrap,
         self.UnWrap,) = _SECKEY_HEADER.STRUCT.unpack(buffer)


class _UNLOCK_BLOB(object):
    STRUCT = Struct('> 8s 24s 16s')

    def __init__(self, buffer):
        (self.CommonBlobBuffer, self.MasterKey, self.BlobSignature) = _UNLOCK_BLOB.STRUCT.unpack(buffer)

        self.CommonBlob = _COMMON_BLOB(self.CommonBlobBuffer)


class _KEYCHAIN_TIME(object):
    STRUCT = Struct('>16s')
    STRPTIME_FORMAT = "%Y%m%d%H%M%SZ"

    def __init__(self, buffer):
        self.Value = _KEYCHAIN_TIME.STRUCT.unpack(buffer)[0].strip('\x00')
        self.Time = datetime.strptime(self.Value, _KEYCHAIN_TIME.STRPTIME_FORMAT)

    def __repr__(self):
        return


class _INT(object):
    STRUCT = Struct('>I')

    def __init__(self, buffer):
        self.Value = _INT.STRUCT.unpack(buffer)[0]


class _FOUR_CHAR_CODE(object):
    STRUCT = Struct('>4s')

    def __init__(self, buffer):
        self.Value = _FOUR_CHAR_CODE.STRUCT.unpack(buffer)[0]


class _LV(object):
    def __init__(self, buffer, length):
        self.STRUCT = Struct(">" + str(length) + "s")
        self.Value = self.STRUCT.unpack(buffer)[0].strip('\x00')


class _RECORD_OFFSET(_INT):
    pass


class _TABLE_ID(_INT):
    pass