# This file is part of Scapy # See http://www.secdev.org/projects/scapy for more information # Copyright (C) Philippe Biondi # Enhanced by Maxence Tury # This program is published under a GPLv2 license """ X.509 certificates. """ from scapy.asn1.mib import conf # loads conf.mib from scapy.asn1.asn1 import ASN1_Codecs, ASN1_OID, \ ASN1_IA5_STRING, ASN1_NULL, ASN1_PRINTABLE_STRING, \ ASN1_UTC_TIME, ASN1_UTF8_STRING from scapy.asn1.ber import BER_tagging_dec, BER_Decoding_Error from scapy.asn1packet import ASN1_Packet from scapy.asn1fields import ASN1F_BIT_STRING, ASN1F_BIT_STRING_ENCAPS, \ ASN1F_BMP_STRING, ASN1F_BOOLEAN, ASN1F_CHOICE, ASN1F_ENUMERATED, \ ASN1F_FLAGS, ASN1F_GENERALIZED_TIME, ASN1F_IA5_STRING, ASN1F_INTEGER, \ ASN1F_ISO646_STRING, ASN1F_NULL, ASN1F_OID, ASN1F_PACKET, \ ASN1F_PRINTABLE_STRING, ASN1F_SEQUENCE, ASN1F_SEQUENCE_OF, ASN1F_SET_OF, \ ASN1F_STRING, ASN1F_T61_STRING, ASN1F_UNIVERSAL_STRING, ASN1F_UTC_TIME, \ ASN1F_UTF8_STRING, ASN1F_badsequence, ASN1F_enum_INTEGER, ASN1F_field, \ ASN1F_optional from scapy.packet import Packet from scapy.fields import PacketField from scapy.volatile import ZuluTime, GeneralizedTime from scapy.compat import plain_str class ASN1P_OID(ASN1_Packet): ASN1_codec = ASN1_Codecs.BER ASN1_root = ASN1F_OID("oid", "0") class ASN1P_INTEGER(ASN1_Packet): ASN1_codec = ASN1_Codecs.BER ASN1_root = ASN1F_INTEGER("number", 0) class ASN1P_PRIVSEQ(ASN1_Packet): # This class gets used in x509.uts # It showcases the private high-tag decoding capacities of scapy. ASN1_codec = ASN1_Codecs.BER ASN1_root = ASN1F_SEQUENCE( ASN1F_IA5_STRING("str", ""), ASN1F_STRING("int", 0), explicit_tag=0, flexible_tag=True) ####################### # RSA packets # ####################### # based on RFC 3447 # It could be interesting to use os.urandom and try to generate # a new modulus each time RSAPublicKey is called with default values. # (We might have to dig into scapy field initialization mechanisms...) # NEVER rely on the key below, which is provided only for debugging purposes. class RSAPublicKey(ASN1_Packet): ASN1_codec = ASN1_Codecs.BER ASN1_root = ASN1F_SEQUENCE( ASN1F_INTEGER("modulus", 10), ASN1F_INTEGER("publicExponent", 3)) class RSAOtherPrimeInfo(ASN1_Packet): ASN1_codec = ASN1_Codecs.BER ASN1_root = ASN1F_SEQUENCE( ASN1F_INTEGER("prime", 0), ASN1F_INTEGER("exponent", 0), ASN1F_INTEGER("coefficient", 0)) class RSAPrivateKey(ASN1_Packet): ASN1_codec = ASN1_Codecs.BER ASN1_root = ASN1F_SEQUENCE( ASN1F_enum_INTEGER("version", 0, ["two-prime", "multi"]), ASN1F_INTEGER("modulus", 10), ASN1F_INTEGER("publicExponent", 3), ASN1F_INTEGER("privateExponent", 3), ASN1F_INTEGER("prime1", 2), ASN1F_INTEGER("prime2", 5), ASN1F_INTEGER("exponent1", 0), ASN1F_INTEGER("exponent2", 3), ASN1F_INTEGER("coefficient", 1), ASN1F_optional( ASN1F_SEQUENCE_OF("otherPrimeInfos", None, RSAOtherPrimeInfo))) #################################### # ECDSA packets # #################################### # based on RFC 3279 & 5480 & 5915 class ECFieldID(ASN1_Packet): # No characteristic-two-field support for now. ASN1_codec = ASN1_Codecs.BER ASN1_root = ASN1F_SEQUENCE( ASN1F_OID("fieldType", "prime-field"), ASN1F_INTEGER("prime", 0)) class ECCurve(ASN1_Packet): ASN1_codec = ASN1_Codecs.BER ASN1_root = ASN1F_SEQUENCE( ASN1F_STRING("a", ""), ASN1F_STRING("b", ""), ASN1F_optional( ASN1F_BIT_STRING("seed", None))) class ECSpecifiedDomain(ASN1_Packet): ASN1_codec = ASN1_Codecs.BER ASN1_root = ASN1F_SEQUENCE( ASN1F_enum_INTEGER("version", 1, {1: "ecpVer1"}), ASN1F_PACKET("fieldID", ECFieldID(), ECFieldID), ASN1F_PACKET("curve", ECCurve(), ECCurve), ASN1F_STRING("base", ""), ASN1F_INTEGER("order", 0), ASN1F_optional( ASN1F_INTEGER("cofactor", None))) class ECParameters(ASN1_Packet): ASN1_codec = ASN1_Codecs.BER ASN1_root = ASN1F_CHOICE("curve", ASN1_OID("ansip384r1"), ASN1F_OID, # for named curves ASN1F_NULL, # for implicit curves ECSpecifiedDomain) class ECDSAPublicKey(ASN1_Packet): ASN1_codec = ASN1_Codecs.BER ASN1_root = ASN1F_BIT_STRING("ecPoint", "") class ECDSAPrivateKey(ASN1_Packet): ASN1_codec = ASN1_Codecs.BER ASN1_root = ASN1F_SEQUENCE( ASN1F_enum_INTEGER("version", 1, {1: "ecPrivkeyVer1"}), ASN1F_STRING("privateKey", ""), ASN1F_optional( ASN1F_PACKET("parameters", None, ECParameters, explicit_tag=0xa0)), ASN1F_optional( ASN1F_PACKET("publicKey", None, ECDSAPublicKey, explicit_tag=0xa1))) class ECDSASignature(ASN1_Packet): ASN1_codec = ASN1_Codecs.BER ASN1_root = ASN1F_SEQUENCE( ASN1F_INTEGER("r", 0), ASN1F_INTEGER("s", 0)) ###################### # X509 packets # ###################### # based on RFC 5280 # Names # class ASN1F_X509_DirectoryString(ASN1F_CHOICE): # we include ASN1 bit strings for rare instances of x500 addresses def __init__(self, name, default, **kwargs): ASN1F_CHOICE.__init__(self, name, default, ASN1F_PRINTABLE_STRING, ASN1F_UTF8_STRING, ASN1F_IA5_STRING, ASN1F_T61_STRING, ASN1F_UNIVERSAL_STRING, ASN1F_BIT_STRING, **kwargs) class X509_AttributeValue(ASN1_Packet): ASN1_codec = ASN1_Codecs.BER ASN1_root = ASN1F_CHOICE("value", ASN1_PRINTABLE_STRING("FR"), ASN1F_PRINTABLE_STRING, ASN1F_UTF8_STRING, ASN1F_IA5_STRING, ASN1F_T61_STRING, ASN1F_UNIVERSAL_STRING) class X509_Attribute(ASN1_Packet): ASN1_codec = ASN1_Codecs.BER ASN1_root = ASN1F_SEQUENCE( ASN1F_OID("type", "2.5.4.6"), ASN1F_SET_OF("values", [X509_AttributeValue()], X509_AttributeValue)) class X509_AttributeTypeAndValue(ASN1_Packet): ASN1_codec = ASN1_Codecs.BER ASN1_root = ASN1F_SEQUENCE( ASN1F_OID("type", "2.5.4.6"), ASN1F_X509_DirectoryString("value", ASN1_PRINTABLE_STRING("FR"))) class X509_RDN(ASN1_Packet): ASN1_codec = ASN1_Codecs.BER ASN1_root = ASN1F_SET_OF("rdn", [X509_AttributeTypeAndValue()], X509_AttributeTypeAndValue) class X509_OtherName(ASN1_Packet): ASN1_codec = ASN1_Codecs.BER ASN1_root = ASN1F_SEQUENCE( ASN1F_OID("type_id", "0"), ASN1F_CHOICE("value", None, ASN1F_IA5_STRING, ASN1F_ISO646_STRING, ASN1F_BMP_STRING, ASN1F_UTF8_STRING, explicit_tag=0xa0)) class X509_RFC822Name(ASN1_Packet): ASN1_codec = ASN1_Codecs.BER ASN1_root = ASN1F_IA5_STRING("rfc822Name", "") class X509_DNSName(ASN1_Packet): ASN1_codec = ASN1_Codecs.BER ASN1_root = ASN1F_IA5_STRING("dNSName", "") # XXX write me class X509_X400Address(ASN1_Packet): ASN1_codec = ASN1_Codecs.BER ASN1_root = ASN1F_field("x400Address", "") _default_directoryName = [ X509_RDN(), X509_RDN( rdn=[X509_AttributeTypeAndValue( type="2.5.4.10", value=ASN1_PRINTABLE_STRING("Scapy, Inc."))]), X509_RDN( rdn=[X509_AttributeTypeAndValue( type="2.5.4.3", value=ASN1_PRINTABLE_STRING("Scapy Default Name"))]) ] class X509_DirectoryName(ASN1_Packet): ASN1_codec = ASN1_Codecs.BER ASN1_root = ASN1F_SEQUENCE_OF("directoryName", _default_directoryName, X509_RDN) class X509_EDIPartyName(ASN1_Packet): ASN1_codec = ASN1_Codecs.BER ASN1_root = ASN1F_SEQUENCE( ASN1F_optional( ASN1F_X509_DirectoryString("nameAssigner", None, explicit_tag=0xa0)), ASN1F_X509_DirectoryString("partyName", None, explicit_tag=0xa1)) class X509_URI(ASN1_Packet): ASN1_codec = ASN1_Codecs.BER ASN1_root = ASN1F_IA5_STRING("uniformResourceIdentifier", "") class X509_IPAddress(ASN1_Packet): ASN1_codec = ASN1_Codecs.BER ASN1_root = ASN1F_STRING("iPAddress", "") class X509_RegisteredID(ASN1_Packet): ASN1_codec = ASN1_Codecs.BER ASN1_root = ASN1F_OID("registeredID", "") class X509_GeneralName(ASN1_Packet): ASN1_codec = ASN1_Codecs.BER ASN1_root = ASN1F_CHOICE("generalName", X509_DirectoryName(), ASN1F_PACKET("otherName", None, X509_OtherName, implicit_tag=0xa0), ASN1F_PACKET("rfc822Name", None, X509_RFC822Name, implicit_tag=0x81), ASN1F_PACKET("dNSName", None, X509_DNSName, implicit_tag=0x82), ASN1F_PACKET("x400Address", None, X509_X400Address, # noqa: E501 explicit_tag=0xa3), ASN1F_PACKET("directoryName", None, X509_DirectoryName, # noqa: E501 explicit_tag=0xa4), ASN1F_PACKET("ediPartyName", None, X509_EDIPartyName, # noqa: E501 explicit_tag=0xa5), ASN1F_PACKET("uniformResourceIdentifier", None, X509_URI, # noqa: E501 implicit_tag=0x86), ASN1F_PACKET("ipAddress", None, X509_IPAddress, implicit_tag=0x87), ASN1F_PACKET("registeredID", None, X509_RegisteredID, # noqa: E501 implicit_tag=0x88)) # Extensions # class X509_ExtAuthorityKeyIdentifier(ASN1_Packet): ASN1_codec = ASN1_Codecs.BER ASN1_root = ASN1F_SEQUENCE( ASN1F_optional( ASN1F_STRING("keyIdentifier", b"\xff" * 20, implicit_tag=0x80)), ASN1F_optional( ASN1F_SEQUENCE_OF("authorityCertIssuer", None, X509_GeneralName, implicit_tag=0xa1)), ASN1F_optional( ASN1F_INTEGER("authorityCertSerialNumber", None, implicit_tag=0x82))) class X509_ExtSubjectDirectoryAttributes(ASN1_Packet): ASN1_codec = ASN1_Codecs.BER ASN1_root = ASN1F_SEQUENCE_OF("subjectDirectoryAttributes", [X509_Attribute()], X509_Attribute) class X509_ExtSubjectKeyIdentifier(ASN1_Packet): ASN1_codec = ASN1_Codecs.BER ASN1_root = ASN1F_STRING("keyIdentifier", "xff" * 20) class X509_ExtFullName(ASN1_Packet): ASN1_codec = ASN1_Codecs.BER ASN1_root = ASN1F_SEQUENCE_OF("fullName", [X509_GeneralName()], X509_GeneralName, implicit_tag=0xa0) class X509_ExtNameRelativeToCRLIssuer(ASN1_Packet): ASN1_codec = ASN1_Codecs.BER ASN1_root = ASN1F_PACKET("nameRelativeToCRLIssuer", X509_RDN(), X509_RDN, implicit_tag=0xa1) class X509_ExtDistributionPointName(ASN1_Packet): ASN1_codec = ASN1_Codecs.BER ASN1_root = ASN1F_CHOICE("distributionPointName", None, X509_ExtFullName, X509_ExtNameRelativeToCRLIssuer) _reasons_mapping = ["unused", "keyCompromise", "cACompromise", "affiliationChanged", "superseded", "cessationOfOperation", "certificateHold", "privilegeWithdrawn", "aACompromise"] class X509_ExtDistributionPoint(ASN1_Packet): ASN1_codec = ASN1_Codecs.BER ASN1_root = ASN1F_SEQUENCE( ASN1F_optional( ASN1F_PACKET("distributionPoint", X509_ExtDistributionPointName(), X509_ExtDistributionPointName, explicit_tag=0xa0)), ASN1F_optional( ASN1F_FLAGS("reasons", None, _reasons_mapping, implicit_tag=0x81)), ASN1F_optional( ASN1F_SEQUENCE_OF("cRLIssuer", None, X509_GeneralName, implicit_tag=0xa2))) _ku_mapping = ["digitalSignature", "nonRepudiation", "keyEncipherment", "dataEncipherment", "keyAgreement", "keyCertSign", "cRLSign", "encipherOnly", "decipherOnly"] class X509_ExtKeyUsage(ASN1_Packet): ASN1_codec = ASN1_Codecs.BER ASN1_root = ASN1F_FLAGS("keyUsage", "101", _ku_mapping) def get_keyUsage(self): return self.ASN1_root.get_flags(self) class X509_ExtPrivateKeyUsagePeriod(ASN1_Packet): ASN1_codec = ASN1_Codecs.BER ASN1_root = ASN1F_SEQUENCE( ASN1F_optional( ASN1F_GENERALIZED_TIME("notBefore", str(GeneralizedTime(-600)), implicit_tag=0x80)), ASN1F_optional( ASN1F_GENERALIZED_TIME("notAfter", str(GeneralizedTime(+86400)), implicit_tag=0x81))) class X509_PolicyMapping(ASN1_Packet): ASN1_codec = ASN1_Codecs.BER ASN1_root = ASN1F_SEQUENCE( ASN1F_OID("issuerDomainPolicy", None), ASN1F_OID("subjectDomainPolicy", None)) class X509_ExtPolicyMappings(ASN1_Packet): ASN1_codec = ASN1_Codecs.BER ASN1_root = ASN1F_SEQUENCE_OF("policyMappings", [], X509_PolicyMapping) class X509_ExtBasicConstraints(ASN1_Packet): # The cA field should not be optional, but some certs omit it for False. ASN1_codec = ASN1_Codecs.BER ASN1_root = ASN1F_SEQUENCE( ASN1F_optional( ASN1F_BOOLEAN("cA", False)), ASN1F_optional( ASN1F_INTEGER("pathLenConstraint", None))) class X509_ExtCRLNumber(ASN1_Packet): ASN1_codec = ASN1_Codecs.BER ASN1_root = ASN1F_INTEGER("cRLNumber", 0) _cRL_reasons = ["unspecified", "keyCompromise", "cACompromise", "affiliationChanged", "superseded", "cessationOfOperation", "certificateHold", "unused_reasonCode", "removeFromCRL", "privilegeWithdrawn", "aACompromise"] class X509_ExtReasonCode(ASN1_Packet): ASN1_codec = ASN1_Codecs.BER ASN1_root = ASN1F_ENUMERATED("cRLReason", 0, _cRL_reasons) class X509_ExtDeltaCRLIndicator(ASN1_Packet): ASN1_codec = ASN1_Codecs.BER ASN1_root = ASN1F_INTEGER("deltaCRLIndicator", 0) class X509_ExtIssuingDistributionPoint(ASN1_Packet): ASN1_codec = ASN1_Codecs.BER ASN1_root = ASN1F_SEQUENCE( ASN1F_optional( ASN1F_PACKET("distributionPoint", X509_ExtDistributionPointName(), X509_ExtDistributionPointName, explicit_tag=0xa0)), ASN1F_BOOLEAN("onlyContainsUserCerts", False, implicit_tag=0x81), ASN1F_BOOLEAN("onlyContainsCACerts", False, implicit_tag=0x82), ASN1F_optional( ASN1F_FLAGS("onlySomeReasons", None, _reasons_mapping, implicit_tag=0x83)), ASN1F_BOOLEAN("indirectCRL", False, implicit_tag=0x84), ASN1F_BOOLEAN("onlyContainsAttributeCerts", False, implicit_tag=0x85)) class X509_ExtCertificateIssuer(ASN1_Packet): ASN1_codec = ASN1_Codecs.BER ASN1_root = ASN1F_SEQUENCE_OF("certificateIssuer", [], X509_GeneralName) class X509_ExtInvalidityDate(ASN1_Packet): ASN1_codec = ASN1_Codecs.BER ASN1_root = ASN1F_GENERALIZED_TIME("invalidityDate", str(ZuluTime(+86400))) class X509_ExtSubjectAltName(ASN1_Packet): ASN1_codec = ASN1_Codecs.BER ASN1_root = ASN1F_SEQUENCE_OF("subjectAltName", [], X509_GeneralName) class X509_ExtIssuerAltName(ASN1_Packet): ASN1_codec = ASN1_Codecs.BER ASN1_root = ASN1F_SEQUENCE_OF("issuerAltName", [], X509_GeneralName) class X509_ExtGeneralSubtree(ASN1_Packet): # 'minimum' is not optional in RFC 5280, yet it is in some implementations. ASN1_codec = ASN1_Codecs.BER ASN1_root = ASN1F_SEQUENCE( ASN1F_PACKET("base", X509_GeneralName(), X509_GeneralName), ASN1F_optional( ASN1F_INTEGER("minimum", None, implicit_tag=0x80)), ASN1F_optional( ASN1F_INTEGER("maximum", None, implicit_tag=0x81))) class X509_ExtNameConstraints(ASN1_Packet): ASN1_codec = ASN1_Codecs.BER ASN1_root = ASN1F_SEQUENCE( ASN1F_optional( ASN1F_SEQUENCE_OF("permittedSubtrees", None, X509_ExtGeneralSubtree, implicit_tag=0xa0)), ASN1F_optional( ASN1F_SEQUENCE_OF("excludedSubtrees", None, X509_ExtGeneralSubtree, implicit_tag=0xa1))) class X509_ExtPolicyConstraints(ASN1_Packet): ASN1_codec = ASN1_Codecs.BER ASN1_root = ASN1F_SEQUENCE( ASN1F_optional( ASN1F_INTEGER("requireExplicitPolicy", None, implicit_tag=0x80)), ASN1F_optional( ASN1F_INTEGER("inhibitPolicyMapping", None, implicit_tag=0x81))) class X509_ExtExtendedKeyUsage(ASN1_Packet): ASN1_codec = ASN1_Codecs.BER ASN1_root = ASN1F_SEQUENCE_OF("extendedKeyUsage", [], ASN1P_OID) def get_extendedKeyUsage(self): eku_array = self.extendedKeyUsage return [eku.oid.oidname for eku in eku_array] class X509_ExtNoticeReference(ASN1_Packet): ASN1_codec = ASN1_Codecs.BER ASN1_root = ASN1F_SEQUENCE( ASN1F_CHOICE("organization", ASN1_UTF8_STRING("Dummy Organization"), ASN1F_IA5_STRING, ASN1F_ISO646_STRING, ASN1F_BMP_STRING, ASN1F_UTF8_STRING), ASN1F_SEQUENCE_OF("noticeNumbers", [], ASN1P_INTEGER)) class X509_ExtUserNotice(ASN1_Packet): ASN1_codec = ASN1_Codecs.BER ASN1_root = ASN1F_SEQUENCE( ASN1F_optional( ASN1F_PACKET("noticeRef", None, X509_ExtNoticeReference)), ASN1F_optional( ASN1F_CHOICE("explicitText", ASN1_UTF8_STRING("Dummy ExplicitText"), ASN1F_IA5_STRING, ASN1F_ISO646_STRING, ASN1F_BMP_STRING, ASN1F_UTF8_STRING))) class X509_ExtPolicyQualifierInfo(ASN1_Packet): ASN1_codec = ASN1_Codecs.BER ASN1_root = ASN1F_SEQUENCE( ASN1F_OID("policyQualifierId", "1.3.6.1.5.5.7.2.1"), ASN1F_CHOICE("qualifier", ASN1_IA5_STRING("cps_str"), ASN1F_IA5_STRING, X509_ExtUserNotice)) class X509_ExtPolicyInformation(ASN1_Packet): ASN1_codec = ASN1_Codecs.BER ASN1_root = ASN1F_SEQUENCE( ASN1F_OID("policyIdentifier", "2.5.29.32.0"), ASN1F_optional( ASN1F_SEQUENCE_OF("policyQualifiers", None, X509_ExtPolicyQualifierInfo))) class X509_ExtCertificatePolicies(ASN1_Packet): ASN1_codec = ASN1_Codecs.BER ASN1_root = ASN1F_SEQUENCE_OF("certificatePolicies", [X509_ExtPolicyInformation()], X509_ExtPolicyInformation) class X509_ExtCRLDistributionPoints(ASN1_Packet): ASN1_codec = ASN1_Codecs.BER ASN1_root = ASN1F_SEQUENCE_OF("cRLDistributionPoints", [X509_ExtDistributionPoint()], X509_ExtDistributionPoint) class X509_ExtInhibitAnyPolicy(ASN1_Packet): ASN1_codec = ASN1_Codecs.BER ASN1_root = ASN1F_INTEGER("skipCerts", 0) class X509_ExtFreshestCRL(ASN1_Packet): ASN1_codec = ASN1_Codecs.BER ASN1_root = ASN1F_SEQUENCE_OF("cRLDistributionPoints", [X509_ExtDistributionPoint()], X509_ExtDistributionPoint) class X509_AccessDescription(ASN1_Packet): ASN1_codec = ASN1_Codecs.BER ASN1_root = ASN1F_SEQUENCE( ASN1F_OID("accessMethod", "0"), ASN1F_PACKET("accessLocation", X509_GeneralName(), X509_GeneralName)) class X509_ExtAuthInfoAccess(ASN1_Packet): ASN1_codec = ASN1_Codecs.BER ASN1_root = ASN1F_SEQUENCE_OF("authorityInfoAccess", [X509_AccessDescription()], X509_AccessDescription) class X509_ExtQcStatement(ASN1_Packet): ASN1_codec = ASN1_Codecs.BER ASN1_root = ASN1F_SEQUENCE( ASN1F_OID("statementId", "0.4.0.1862.1.1"), ASN1F_optional( ASN1F_field("statementInfo", None))) class X509_ExtQcStatements(ASN1_Packet): ASN1_codec = ASN1_Codecs.BER ASN1_root = ASN1F_SEQUENCE_OF("qcStatements", [X509_ExtQcStatement()], X509_ExtQcStatement) class X509_ExtSubjInfoAccess(ASN1_Packet): ASN1_codec = ASN1_Codecs.BER ASN1_root = ASN1F_SEQUENCE_OF("subjectInfoAccess", [X509_AccessDescription()], X509_AccessDescription) class X509_ExtNetscapeCertType(ASN1_Packet): ASN1_codec = ASN1_Codecs.BER ASN1_root = ASN1F_BIT_STRING("netscapeCertType", "") class X509_ExtComment(ASN1_Packet): ASN1_codec = ASN1_Codecs.BER ASN1_root = ASN1F_CHOICE("comment", ASN1_UTF8_STRING("Dummy comment."), ASN1F_IA5_STRING, ASN1F_ISO646_STRING, ASN1F_BMP_STRING, ASN1F_UTF8_STRING) class X509_ExtDefault(ASN1_Packet): ASN1_codec = ASN1_Codecs.BER ASN1_root = ASN1F_field("value", None) # oid-info.com shows that some extensions share multiple OIDs. # Here we only reproduce those written in RFC5280. _ext_mapping = { "2.5.29.9": X509_ExtSubjectDirectoryAttributes, "2.5.29.14": X509_ExtSubjectKeyIdentifier, "2.5.29.15": X509_ExtKeyUsage, "2.5.29.16": X509_ExtPrivateKeyUsagePeriod, "2.5.29.17": X509_ExtSubjectAltName, "2.5.29.18": X509_ExtIssuerAltName, "2.5.29.19": X509_ExtBasicConstraints, "2.5.29.20": X509_ExtCRLNumber, "2.5.29.21": X509_ExtReasonCode, "2.5.29.24": X509_ExtInvalidityDate, "2.5.29.27": X509_ExtDeltaCRLIndicator, "2.5.29.28": X509_ExtIssuingDistributionPoint, "2.5.29.29": X509_ExtCertificateIssuer, "2.5.29.30": X509_ExtNameConstraints, "2.5.29.31": X509_ExtCRLDistributionPoints, "2.5.29.32": X509_ExtCertificatePolicies, "2.5.29.33": X509_ExtPolicyMappings, "2.5.29.35": X509_ExtAuthorityKeyIdentifier, "2.5.29.36": X509_ExtPolicyConstraints, "2.5.29.37": X509_ExtExtendedKeyUsage, "2.5.29.46": X509_ExtFreshestCRL, "2.5.29.54": X509_ExtInhibitAnyPolicy, "2.16.840.1.113730.1.1": X509_ExtNetscapeCertType, "2.16.840.1.113730.1.13": X509_ExtComment, "1.3.6.1.5.5.7.1.1": X509_ExtAuthInfoAccess, "1.3.6.1.5.5.7.1.3": X509_ExtQcStatements, "1.3.6.1.5.5.7.1.11": X509_ExtSubjInfoAccess } class ASN1F_EXT_SEQUENCE(ASN1F_SEQUENCE): # We use explicit_tag=0x04 with extnValue as STRING encapsulation. def __init__(self, **kargs): seq = [ASN1F_OID("extnID", "2.5.29.19"), ASN1F_optional( ASN1F_BOOLEAN("critical", False)), ASN1F_PACKET("extnValue", X509_ExtBasicConstraints(), X509_ExtBasicConstraints, explicit_tag=0x04)] ASN1F_SEQUENCE.__init__(self, *seq, **kargs) def dissect(self, pkt, s): _, s = BER_tagging_dec(s, implicit_tag=self.implicit_tag, explicit_tag=self.explicit_tag, safe=self.flexible_tag) codec = self.ASN1_tag.get_codec(pkt.ASN1_codec) i, s, remain = codec.check_type_check_len(s) extnID = self.seq[0] critical = self.seq[1] try: oid, s = extnID.m2i(pkt, s) extnID.set_val(pkt, oid) s = critical.dissect(pkt, s) encapsed = X509_ExtDefault if oid.val in _ext_mapping: encapsed = _ext_mapping[oid.val] self.seq[2].cls = encapsed self.seq[2].cls.ASN1_root.flexible_tag = True # there are too many private extensions not to be flexible here self.seq[2].default = encapsed() s = self.seq[2].dissect(pkt, s) if not self.flexible_tag and len(s) > 0: err_msg = "extension sequence length issue" raise BER_Decoding_Error(err_msg, remaining=s) except ASN1F_badsequence: raise Exception("could not parse extensions") return remain class X509_Extension(ASN1_Packet): ASN1_codec = ASN1_Codecs.BER ASN1_root = ASN1F_EXT_SEQUENCE() class X509_Extensions(ASN1_Packet): # we use this in OCSP status requests, in tls/handshake.py ASN1_codec = ASN1_Codecs.BER ASN1_root = ASN1F_optional( ASN1F_SEQUENCE_OF("extensions", None, X509_Extension)) # Public key wrapper # class X509_AlgorithmIdentifier(ASN1_Packet): ASN1_codec = ASN1_Codecs.BER ASN1_root = ASN1F_SEQUENCE( ASN1F_OID("algorithm", "1.2.840.113549.1.1.11"), ASN1F_optional( ASN1F_CHOICE("parameters", ASN1_NULL(0), ASN1F_NULL, ECParameters))) class ASN1F_X509_SubjectPublicKeyInfoRSA(ASN1F_SEQUENCE): def __init__(self, **kargs): seq = [ASN1F_PACKET("signatureAlgorithm", X509_AlgorithmIdentifier(), X509_AlgorithmIdentifier), ASN1F_BIT_STRING_ENCAPS("subjectPublicKey", RSAPublicKey(), RSAPublicKey)] ASN1F_SEQUENCE.__init__(self, *seq, **kargs) class ASN1F_X509_SubjectPublicKeyInfoECDSA(ASN1F_SEQUENCE): def __init__(self, **kargs): seq = [ASN1F_PACKET("signatureAlgorithm", X509_AlgorithmIdentifier(), X509_AlgorithmIdentifier), ASN1F_PACKET("subjectPublicKey", ECDSAPublicKey(), ECDSAPublicKey)] ASN1F_SEQUENCE.__init__(self, *seq, **kargs) class ASN1F_X509_SubjectPublicKeyInfo(ASN1F_SEQUENCE): def __init__(self, **kargs): seq = [ASN1F_PACKET("signatureAlgorithm", X509_AlgorithmIdentifier(), X509_AlgorithmIdentifier), ASN1F_BIT_STRING("subjectPublicKey", None)] ASN1F_SEQUENCE.__init__(self, *seq, **kargs) def m2i(self, pkt, x): c, s = ASN1F_SEQUENCE.m2i(self, pkt, x) keytype = pkt.fields["signatureAlgorithm"].algorithm.oidname if "rsa" in keytype.lower(): return ASN1F_X509_SubjectPublicKeyInfoRSA().m2i(pkt, x) elif keytype == "ecPublicKey": return ASN1F_X509_SubjectPublicKeyInfoECDSA().m2i(pkt, x) else: raise Exception("could not parse subjectPublicKeyInfo") def dissect(self, pkt, s): c, x = self.m2i(pkt, s) return x def build(self, pkt): if "signatureAlgorithm" in pkt.fields: ktype = pkt.fields['signatureAlgorithm'].algorithm.oidname else: ktype = pkt.default_fields["signatureAlgorithm"].algorithm.oidname if "rsa" in ktype.lower(): pkt.default_fields["subjectPublicKey"] = RSAPublicKey() return ASN1F_X509_SubjectPublicKeyInfoRSA().build(pkt) elif ktype == "ecPublicKey": pkt.default_fields["subjectPublicKey"] = ECDSAPublicKey() return ASN1F_X509_SubjectPublicKeyInfoECDSA().build(pkt) else: raise Exception("could not build subjectPublicKeyInfo") class X509_SubjectPublicKeyInfo(ASN1_Packet): ASN1_codec = ASN1_Codecs.BER ASN1_root = ASN1F_X509_SubjectPublicKeyInfo() # OpenSSL compatibility wrappers # # XXX As ECDSAPrivateKey already uses the structure from RFC 5958, # and as we would prefer encapsulated RSA private keys to be parsed, # this lazy implementation actually supports RSA encoding only. # We'd rather call it RSAPrivateKey_OpenSSL than X509_PrivateKeyInfo. class RSAPrivateKey_OpenSSL(ASN1_Packet): ASN1_codec = ASN1_Codecs.BER ASN1_root = ASN1F_SEQUENCE( ASN1F_enum_INTEGER("version", 0, ["v1", "v2"]), ASN1F_PACKET("privateKeyAlgorithm", X509_AlgorithmIdentifier(), X509_AlgorithmIdentifier), ASN1F_PACKET("privateKey", RSAPrivateKey(), RSAPrivateKey, explicit_tag=0x04), ASN1F_optional( ASN1F_PACKET("parameters", None, ECParameters, explicit_tag=0xa0)), ASN1F_optional( ASN1F_PACKET("publicKey", None, ECDSAPublicKey, explicit_tag=0xa1))) # We need this hack because ECParameters parsing below must return # a Padding payload, and making the ASN1_Packet class have Padding # instead of Raw payload would break things... class _PacketFieldRaw(PacketField): def getfield(self, pkt, s): i = self.m2i(pkt, s) remain = "" if conf.raw_layer in i: r = i[conf.raw_layer] del(r.underlayer.payload) remain = r.load return remain, i class ECDSAPrivateKey_OpenSSL(Packet): name = "ECDSA Params + Private Key" fields_desc = [_PacketFieldRaw("ecparam", ECParameters(), ECParameters), PacketField("privateKey", ECDSAPrivateKey(), ECDSAPrivateKey)] # TBSCertificate & Certificate # _default_issuer = [ X509_RDN(), X509_RDN( rdn=[X509_AttributeTypeAndValue( type="2.5.4.10", value=ASN1_PRINTABLE_STRING("Scapy, Inc."))]), X509_RDN( rdn=[X509_AttributeTypeAndValue( type="2.5.4.3", value=ASN1_PRINTABLE_STRING("Scapy Default Issuer"))]) ] _default_subject = [ X509_RDN(), X509_RDN( rdn=[X509_AttributeTypeAndValue( type="2.5.4.10", value=ASN1_PRINTABLE_STRING("Scapy, Inc."))]), X509_RDN( rdn=[X509_AttributeTypeAndValue( type="2.5.4.3", value=ASN1_PRINTABLE_STRING("Scapy Default Subject"))]) ] class X509_Validity(ASN1_Packet): ASN1_codec = ASN1_Codecs.BER ASN1_root = ASN1F_SEQUENCE( ASN1F_CHOICE("not_before", ASN1_UTC_TIME(str(ZuluTime(-600))), ASN1F_UTC_TIME, ASN1F_GENERALIZED_TIME), ASN1F_CHOICE("not_after", ASN1_UTC_TIME(str(ZuluTime(+86400))), ASN1F_UTC_TIME, ASN1F_GENERALIZED_TIME)) _attrName_mapping = [ ("countryName", "C"), ("stateOrProvinceName", "ST"), ("localityName", "L"), ("organizationName", "O"), ("organizationUnitName", "OU"), ("commonName", "CN") ] _attrName_specials = [name for name, symbol in _attrName_mapping] class X509_TBSCertificate(ASN1_Packet): ASN1_codec = ASN1_Codecs.BER ASN1_root = ASN1F_SEQUENCE( ASN1F_optional( ASN1F_enum_INTEGER("version", 0x2, ["v1", "v2", "v3"], explicit_tag=0xa0)), ASN1F_INTEGER("serialNumber", 1), ASN1F_PACKET("signature", X509_AlgorithmIdentifier(), X509_AlgorithmIdentifier), ASN1F_SEQUENCE_OF("issuer", _default_issuer, X509_RDN), ASN1F_PACKET("validity", X509_Validity(), X509_Validity), ASN1F_SEQUENCE_OF("subject", _default_subject, X509_RDN), ASN1F_PACKET("subjectPublicKeyInfo", X509_SubjectPublicKeyInfo(), X509_SubjectPublicKeyInfo), ASN1F_optional( ASN1F_BIT_STRING("issuerUniqueID", None, implicit_tag=0x81)), ASN1F_optional( ASN1F_BIT_STRING("subjectUniqueID", None, implicit_tag=0x82)), ASN1F_optional( ASN1F_SEQUENCE_OF("extensions", [X509_Extension()], X509_Extension, explicit_tag=0xa3))) def get_issuer(self): attrs = self.issuer attrsDict = {} for attr in attrs: # we assume there is only one name in each rdn ASN1_SET attrsDict[attr.rdn[0].type.oidname] = plain_str(attr.rdn[0].value.val) # noqa: E501 return attrsDict def get_issuer_str(self): """ Returns a one-line string containing every type/value in a rather specific order. sorted() built-in ensures unicity. """ name_str = "" attrsDict = self.get_issuer() for attrType, attrSymbol in _attrName_mapping: if attrType in attrsDict: name_str += "/" + attrSymbol + "=" name_str += attrsDict[attrType] for attrType in sorted(attrsDict): if attrType not in _attrName_specials: name_str += "/" + attrType + "=" name_str += attrsDict[attrType] return name_str def get_subject(self): attrs = self.subject attrsDict = {} for attr in attrs: # we assume there is only one name in each rdn ASN1_SET attrsDict[attr.rdn[0].type.oidname] = plain_str(attr.rdn[0].value.val) # noqa: E501 return attrsDict def get_subject_str(self): name_str = "" attrsDict = self.get_subject() for attrType, attrSymbol in _attrName_mapping: if attrType in attrsDict: name_str += "/" + attrSymbol + "=" name_str += attrsDict[attrType] for attrType in sorted(attrsDict): if attrType not in _attrName_specials: name_str += "/" + attrType + "=" name_str += attrsDict[attrType] return name_str class ASN1F_X509_CertECDSA(ASN1F_SEQUENCE): def __init__(self, **kargs): seq = [ASN1F_PACKET("tbsCertificate", X509_TBSCertificate(), X509_TBSCertificate), ASN1F_PACKET("signatureAlgorithm", X509_AlgorithmIdentifier(), X509_AlgorithmIdentifier), ASN1F_BIT_STRING_ENCAPS("signatureValue", ECDSASignature(), ECDSASignature)] ASN1F_SEQUENCE.__init__(self, *seq, **kargs) class ASN1F_X509_Cert(ASN1F_SEQUENCE): def __init__(self, **kargs): seq = [ASN1F_PACKET("tbsCertificate", X509_TBSCertificate(), X509_TBSCertificate), ASN1F_PACKET("signatureAlgorithm", X509_AlgorithmIdentifier(), X509_AlgorithmIdentifier), ASN1F_BIT_STRING("signatureValue", "defaultsignature" * 2)] ASN1F_SEQUENCE.__init__(self, *seq, **kargs) def m2i(self, pkt, x): c, s = ASN1F_SEQUENCE.m2i(self, pkt, x) sigtype = pkt.fields["signatureAlgorithm"].algorithm.oidname if "rsa" in sigtype.lower(): return c, s elif "ecdsa" in sigtype.lower(): return ASN1F_X509_CertECDSA().m2i(pkt, x) else: raise Exception("could not parse certificate") def dissect(self, pkt, s): c, x = self.m2i(pkt, s) return x def build(self, pkt): if "signatureAlgorithm" in pkt.fields: sigtype = pkt.fields['signatureAlgorithm'].algorithm.oidname else: sigtype = pkt.default_fields["signatureAlgorithm"].algorithm.oidname # noqa: E501 if "rsa" in sigtype.lower(): return ASN1F_SEQUENCE.build(self, pkt) elif "ecdsa" in sigtype.lower(): pkt.default_fields["signatureValue"] = ECDSASignature() return ASN1F_X509_CertECDSA().build(pkt) else: raise Exception("could not build certificate") class X509_Cert(ASN1_Packet): ASN1_codec = ASN1_Codecs.BER ASN1_root = ASN1F_X509_Cert() # TBSCertList & CRL # class X509_RevokedCertificate(ASN1_Packet): ASN1_codec = ASN1_Codecs.BER ASN1_root = ASN1F_SEQUENCE(ASN1F_INTEGER("serialNumber", 1), ASN1F_UTC_TIME("revocationDate", str(ZuluTime(+86400))), ASN1F_optional( ASN1F_SEQUENCE_OF("crlEntryExtensions", None, X509_Extension))) class X509_TBSCertList(ASN1_Packet): ASN1_codec = ASN1_Codecs.BER ASN1_root = ASN1F_SEQUENCE( ASN1F_optional( ASN1F_enum_INTEGER("version", 1, ["v1", "v2"])), ASN1F_PACKET("signature", X509_AlgorithmIdentifier(), X509_AlgorithmIdentifier), ASN1F_SEQUENCE_OF("issuer", _default_issuer, X509_RDN), ASN1F_UTC_TIME("this_update", str(ZuluTime(-1))), ASN1F_optional( ASN1F_UTC_TIME("next_update", None)), ASN1F_optional( ASN1F_SEQUENCE_OF("revokedCertificates", None, X509_RevokedCertificate)), ASN1F_optional( ASN1F_SEQUENCE_OF("crlExtensions", None, X509_Extension, explicit_tag=0xa0))) def get_issuer(self): attrs = self.issuer attrsDict = {} for attr in attrs: # we assume there is only one name in each rdn ASN1_SET attrsDict[attr.rdn[0].type.oidname] = plain_str(attr.rdn[0].value.val) # noqa: E501 return attrsDict def get_issuer_str(self): """ Returns a one-line string containing every type/value in a rather specific order. sorted() built-in ensures unicity. """ name_str = "" attrsDict = self.get_issuer() for attrType, attrSymbol in _attrName_mapping: if attrType in attrsDict: name_str += "/" + attrSymbol + "=" name_str += attrsDict[attrType] for attrType in sorted(attrsDict): if attrType not in _attrName_specials: name_str += "/" + attrType + "=" name_str += attrsDict[attrType] return name_str class ASN1F_X509_CRLECDSA(ASN1F_SEQUENCE): def __init__(self, **kargs): seq = [ASN1F_PACKET("tbsCertList", X509_TBSCertList(), X509_TBSCertList), ASN1F_PACKET("signatureAlgorithm", X509_AlgorithmIdentifier(), X509_AlgorithmIdentifier), ASN1F_BIT_STRING_ENCAPS("signatureValue", ECDSASignature(), ECDSASignature)] ASN1F_SEQUENCE.__init__(self, *seq, **kargs) class ASN1F_X509_CRL(ASN1F_SEQUENCE): def __init__(self, **kargs): seq = [ASN1F_PACKET("tbsCertList", X509_TBSCertList(), X509_TBSCertList), ASN1F_PACKET("signatureAlgorithm", X509_AlgorithmIdentifier(), X509_AlgorithmIdentifier), ASN1F_BIT_STRING("signatureValue", "defaultsignature" * 2)] ASN1F_SEQUENCE.__init__(self, *seq, **kargs) def m2i(self, pkt, x): c, s = ASN1F_SEQUENCE.m2i(self, pkt, x) sigtype = pkt.fields["signatureAlgorithm"].algorithm.oidname if "rsa" in sigtype.lower(): return c, s elif "ecdsa" in sigtype.lower(): return ASN1F_X509_CRLECDSA().m2i(pkt, x) else: raise Exception("could not parse certificate") def dissect(self, pkt, s): c, x = self.m2i(pkt, s) return x def build(self, pkt): if "signatureAlgorithm" in pkt.fields: sigtype = pkt.fields['signatureAlgorithm'].algorithm.oidname else: sigtype = pkt.default_fields["signatureAlgorithm"].algorithm.oidname # noqa: E501 if "rsa" in sigtype.lower(): return ASN1F_SEQUENCE.build(self, pkt) elif "ecdsa" in sigtype.lower(): pkt.default_fields["signatureValue"] = ECDSASignature() return ASN1F_X509_CRLECDSA().build(pkt) else: raise Exception("could not build certificate") class X509_CRL(ASN1_Packet): ASN1_codec = ASN1_Codecs.BER ASN1_root = ASN1F_X509_CRL() ############################# # OCSP Status packets # ############################# # based on RFC 6960 class OCSP_CertID(ASN1_Packet): ASN1_codec = ASN1_Codecs.BER ASN1_root = ASN1F_SEQUENCE( ASN1F_PACKET("hashAlgorithm", X509_AlgorithmIdentifier(), X509_AlgorithmIdentifier), ASN1F_STRING("issuerNameHash", ""), ASN1F_STRING("issuerKeyHash", ""), ASN1F_INTEGER("serialNumber", 0)) class OCSP_GoodInfo(ASN1_Packet): ASN1_codec = ASN1_Codecs.BER ASN1_root = ASN1F_NULL("info", 0) class OCSP_RevokedInfo(ASN1_Packet): ASN1_codec = ASN1_Codecs.BER ASN1_root = ASN1F_SEQUENCE( ASN1F_GENERALIZED_TIME("revocationTime", ""), ASN1F_optional( ASN1F_PACKET("revocationReason", None, X509_ExtReasonCode, explicit_tag=0x80))) class OCSP_UnknownInfo(ASN1_Packet): ASN1_codec = ASN1_Codecs.BER ASN1_root = ASN1F_NULL("info", 0) class OCSP_CertStatus(ASN1_Packet): ASN1_codec = ASN1_Codecs.BER ASN1_root = ASN1F_CHOICE("certStatus", None, ASN1F_PACKET("good", OCSP_GoodInfo(), OCSP_GoodInfo, implicit_tag=0x80), ASN1F_PACKET("revoked", OCSP_RevokedInfo(), OCSP_RevokedInfo, implicit_tag=0xa1), ASN1F_PACKET("unknown", OCSP_UnknownInfo(), OCSP_UnknownInfo, implicit_tag=0x82)) class OCSP_SingleResponse(ASN1_Packet): ASN1_codec = ASN1_Codecs.BER ASN1_root = ASN1F_SEQUENCE( ASN1F_PACKET("certID", OCSP_CertID(), OCSP_CertID), ASN1F_PACKET("certStatus", OCSP_CertStatus(), OCSP_CertStatus), ASN1F_GENERALIZED_TIME("thisUpdate", ""), ASN1F_optional( ASN1F_GENERALIZED_TIME("nextUpdate", "", explicit_tag=0xa0)), ASN1F_optional( ASN1F_SEQUENCE_OF("singleExtensions", None, X509_Extension, explicit_tag=0xa1))) class OCSP_ByName(ASN1_Packet): ASN1_codec = ASN1_Codecs.BER ASN1_root = ASN1F_SEQUENCE_OF("byName", [], X509_RDN) class OCSP_ByKey(ASN1_Packet): ASN1_codec = ASN1_Codecs.BER ASN1_root = ASN1F_STRING("byKey", "") class OCSP_ResponderID(ASN1_Packet): ASN1_codec = ASN1_Codecs.BER ASN1_root = ASN1F_CHOICE("responderID", None, ASN1F_PACKET("byName", OCSP_ByName(), OCSP_ByName, explicit_tag=0xa1), ASN1F_PACKET("byKey", OCSP_ByKey(), OCSP_ByKey, explicit_tag=0xa2)) class OCSP_ResponseData(ASN1_Packet): ASN1_codec = ASN1_Codecs.BER ASN1_root = ASN1F_SEQUENCE( ASN1F_optional( ASN1F_enum_INTEGER("version", 0, {0: "v1"}, explicit_tag=0x80)), ASN1F_PACKET("responderID", OCSP_ResponderID(), OCSP_ResponderID), ASN1F_GENERALIZED_TIME("producedAt", str(GeneralizedTime())), ASN1F_SEQUENCE_OF("responses", [], OCSP_SingleResponse), ASN1F_optional( ASN1F_SEQUENCE_OF("responseExtensions", None, X509_Extension, explicit_tag=0xa1))) class ASN1F_OCSP_BasicResponseECDSA(ASN1F_SEQUENCE): def __init__(self, **kargs): seq = [ASN1F_PACKET("tbsResponseData", OCSP_ResponseData(), OCSP_ResponseData), ASN1F_PACKET("signatureAlgorithm", X509_AlgorithmIdentifier(), X509_AlgorithmIdentifier), ASN1F_BIT_STRING_ENCAPS("signature", ECDSASignature(), ECDSASignature), ASN1F_optional( ASN1F_SEQUENCE_OF("certs", None, X509_Cert, explicit_tag=0xa0))] ASN1F_SEQUENCE.__init__(self, *seq, **kargs) class ASN1F_OCSP_BasicResponse(ASN1F_SEQUENCE): def __init__(self, **kargs): seq = [ASN1F_PACKET("tbsResponseData", OCSP_ResponseData(), OCSP_ResponseData), ASN1F_PACKET("signatureAlgorithm", X509_AlgorithmIdentifier(), X509_AlgorithmIdentifier), ASN1F_BIT_STRING("signature", "defaultsignature" * 2), ASN1F_optional( ASN1F_SEQUENCE_OF("certs", None, X509_Cert, explicit_tag=0xa0))] ASN1F_SEQUENCE.__init__(self, *seq, **kargs) def m2i(self, pkt, x): c, s = ASN1F_SEQUENCE.m2i(self, pkt, x) sigtype = pkt.fields["signatureAlgorithm"].algorithm.oidname if "rsa" in sigtype.lower(): return c, s elif "ecdsa" in sigtype.lower(): return ASN1F_OCSP_BasicResponseECDSA().m2i(pkt, x) else: raise Exception("could not parse OCSP basic response") def dissect(self, pkt, s): c, x = self.m2i(pkt, s) return x def build(self, pkt): if "signatureAlgorithm" in pkt.fields: sigtype = pkt.fields['signatureAlgorithm'].algorithm.oidname else: sigtype = pkt.default_fields["signatureAlgorithm"].algorithm.oidname # noqa: E501 if "rsa" in sigtype.lower(): return ASN1F_SEQUENCE.build(self, pkt) elif "ecdsa" in sigtype.lower(): pkt.default_fields["signatureValue"] = ECDSASignature() return ASN1F_OCSP_BasicResponseECDSA().build(pkt) else: raise Exception("could not build OCSP basic response") class OCSP_ResponseBytes(ASN1_Packet): ASN1_codec = ASN1_Codecs.BER ASN1_root = ASN1F_SEQUENCE( ASN1F_OID("responseType", "1.3.6.1.5.5.7.48.1.1"), ASN1F_OCSP_BasicResponse(explicit_tag=0x04)) _responseStatus_mapping = ["successful", "malformedRequest", "internalError", "tryLater", "notUsed", "sigRequired", "unauthorized"] class OCSP_Response(ASN1_Packet): ASN1_codec = ASN1_Codecs.BER ASN1_root = ASN1F_SEQUENCE( ASN1F_ENUMERATED("responseStatus", 0, _responseStatus_mapping), ASN1F_optional( ASN1F_PACKET("responseBytes", None, OCSP_ResponseBytes, explicit_tag=0xa0)))