예제 #1
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def make_ds(name, key, algorithm, origin=None):
    """Create a DS record for a DNSSEC key.

    *name* is the owner name of the DS record.

    *key* is a ``dns.rdtypes.ANY.DNSKEY``.

    *algorithm* is a string describing which hash algorithm to use.  The
    currently supported hashes are "SHA1" and "SHA256".  Case does not
    matter for these strings.

    *origin* is a ``dns.name.Name`` and will be used as the origin
    if *key* is a relative name.

    Returns a ``dns.rdtypes.ANY.DS``.
    """

    if algorithm.upper() == 'SHA1':
        dsalg = 1
        hash = dns.hash.hashes['SHA1']()
    elif algorithm.upper() == 'SHA256':
        dsalg = 2
        hash = dns.hash.hashes['SHA256']()
    else:
        raise UnsupportedAlgorithm('unsupported algorithm "%s"' % algorithm)

    if isinstance(name, string_types):
        name = dns.name.from_text(name, origin)
    hash.update(name.canonicalize().to_wire())
    hash.update(_to_rdata(key, origin))
    digest = hash.digest()

    dsrdata = struct.pack("!HBB", key_id(key), key.algorithm, dsalg) + digest
    return dns.rdata.from_wire(dns.rdataclass.IN, dns.rdatatype.DS, dsrdata, 0,
                               len(dsrdata))
예제 #2
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def make_ds(name, key, algorithm, origin=None):
    """Create a DS record for a DNSSEC key.

    *name* is the owner name of the DS record.

    *key* is a ``dns.rdtypes.ANY.DNSKEY``.

    *algorithm* is a string describing which hash algorithm to use.  The
    currently supported hashes are "SHA1" and "SHA256".  Case does not
    matter for these strings.

    *origin* is a ``dns.name.Name`` and will be used as the origin
    if *key* is a relative name.

    Returns a ``dns.rdtypes.ANY.DS``.
    """

    if algorithm.upper() == 'SHA1':
        dsalg = 1
        hash = dns.hash.hashes['SHA1']()
    elif algorithm.upper() == 'SHA256':
        dsalg = 2
        hash = dns.hash.hashes['SHA256']()
    else:
        raise UnsupportedAlgorithm('unsupported algorithm "%s"' % algorithm)

    if isinstance(name, string_types):
        name = dns.name.from_text(name, origin)
    hash.update(name.canonicalize().to_wire())
    hash.update(_to_rdata(key, origin))
    digest = hash.digest()

    dsrdata = struct.pack("!HBB", key_id(key), key.algorithm, dsalg) + digest
    return dns.rdata.from_wire(dns.rdataclass.IN, dns.rdatatype.DS, dsrdata, 0,
                               len(dsrdata))
예제 #3
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파일: dnssec.py 프로젝트: CheneyHsu/PTest
def make_ds(name, key, algorithm, origin=None):
    if algorithm.upper() == 'SHA1':
        dsalg = 1
        hash = dns.hash.get('SHA1')()
    elif algorithm.upper() == 'SHA256':
        dsalg = 2
        hash = dns.hash.get('SHA256')()
    else:
        raise UnsupportedAlgorithm, 'unsupported algorithm "%s"' % algorithm

    if isinstance(name, (str, unicode)):
        name = dns.name.from_text(name, origin)
    hash.update(name.canonicalize().to_wire())
    hash.update(_to_rdata(key, origin))
    digest = hash.digest()

    dsrdata = struct.pack("!HBB", key_id(key), key.algorithm, dsalg) + digest
    return dns.rdata.from_wire(dns.rdataclass.IN, dns.rdatatype.DS, dsrdata, 0,
                               len(dsrdata))
예제 #4
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파일: dnssec.py 프로젝트: webshell520/llk
def make_ds(name, key, algorithm, origin=None):
    if algorithm.upper() == 'SHA1':
        dsalg = 1
        hash = dns.hash.get('SHA1')()
    elif algorithm.upper() == 'SHA256':
        dsalg = 2
        hash = dns.hash.get('SHA256')()
    else:
        raise UnsupportedAlgorithm, 'unsupported algorithm "%s"' % algorithm

    if isinstance(name, (str, unicode)):
        name = dns.name.from_text(name, origin)
    hash.update(name.canonicalize().to_wire())
    hash.update(_to_rdata(key, origin))
    digest = hash.digest()

    dsrdata = struct.pack("!HBB", key_id(key), key.algorithm, dsalg) + digest
    return dns.rdata.from_wire(dns.rdataclass.IN, dns.rdatatype.DS, dsrdata, 0,
                               len(dsrdata))
예제 #5
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def _validate_rrsig(rrset, rrsig, keys, origin=None, now=None):
    """Validate an RRset against a single signature rdata

    The owner name of *rrsig* is assumed to be the same as the owner name
    of *rrset*.

    *rrset* is the RRset to validate.  It can be a ``dns.rrset.RRset`` or
    a ``(dns.name.Name, dns.rdataset.Rdataset)`` tuple.

    *rrsig* is a ``dns.rrset.Rdata``, the signature to validate.

    *keys* is the key dictionary, used to find the DNSKEY associated with
    a given name.  The dictionary is keyed by a ``dns.name.Name``, and has
    ``dns.node.Node`` or ``dns.rdataset.Rdataset`` values.

    *origin* is a ``dns.name.Name``, the origin to use for relative names.

    *now* is an ``int``, the time to use when validating the signatures,
    in seconds since the UNIX epoch.  The default is the current time.
    """

    if isinstance(origin, string_types):
        origin = dns.name.from_text(origin, dns.name.root)

    candidate_keys = _find_candidate_keys(keys, rrsig)
    if candidate_keys is None:
        raise ValidationFailure('unknown key')

    for candidate_key in candidate_keys:
        # For convenience, allow the rrset to be specified as a (name,
        # rdataset) tuple as well as a proper rrset
        if isinstance(rrset, tuple):
            rrname = rrset[0]
            rdataset = rrset[1]
        else:
            rrname = rrset.name
            rdataset = rrset

        if now is None:
            now = time.time()
        if rrsig.expiration < now:
            raise ValidationFailure('expired')
        if rrsig.inception > now:
            raise ValidationFailure('not yet valid')

        hash = _make_hash(rrsig.algorithm)

        if _is_rsa(rrsig.algorithm):
            keyptr = candidate_key.key
            (bytes_,) = struct.unpack('!B', keyptr[0:1])
            keyptr = keyptr[1:]
            if bytes_ == 0:
                (bytes_,) = struct.unpack('!H', keyptr[0:2])
                keyptr = keyptr[2:]
            rsa_e = keyptr[0:bytes_]
            rsa_n = keyptr[bytes_:]
            keylen = len(rsa_n) * 8
            pubkey = Crypto.PublicKey.RSA.construct(
                (Crypto.Util.number.bytes_to_long(rsa_n),
                 Crypto.Util.number.bytes_to_long(rsa_e)))
            sig = (Crypto.Util.number.bytes_to_long(rrsig.signature),)
        elif _is_dsa(rrsig.algorithm):
            keyptr = candidate_key.key
            (t,) = struct.unpack('!B', keyptr[0:1])
            keyptr = keyptr[1:]
            octets = 64 + t * 8
            dsa_q = keyptr[0:20]
            keyptr = keyptr[20:]
            dsa_p = keyptr[0:octets]
            keyptr = keyptr[octets:]
            dsa_g = keyptr[0:octets]
            keyptr = keyptr[octets:]
            dsa_y = keyptr[0:octets]
            pubkey = Crypto.PublicKey.DSA.construct(
                (Crypto.Util.number.bytes_to_long(dsa_y),
                 Crypto.Util.number.bytes_to_long(dsa_g),
                 Crypto.Util.number.bytes_to_long(dsa_p),
                 Crypto.Util.number.bytes_to_long(dsa_q)))
            (dsa_r, dsa_s) = struct.unpack('!20s20s', rrsig.signature[1:])
            sig = (Crypto.Util.number.bytes_to_long(dsa_r),
                   Crypto.Util.number.bytes_to_long(dsa_s))
        elif _is_ecdsa(rrsig.algorithm):
            if rrsig.algorithm == ECDSAP256SHA256:
                curve = ecdsa.curves.NIST256p
                key_len = 32
            elif rrsig.algorithm == ECDSAP384SHA384:
                curve = ecdsa.curves.NIST384p
                key_len = 48
            else:
                # shouldn't happen
                raise ValidationFailure('unknown ECDSA curve')
            keyptr = candidate_key.key
            x = Crypto.Util.number.bytes_to_long(keyptr[0:key_len])
            y = Crypto.Util.number.bytes_to_long(keyptr[key_len:key_len * 2])
            if not ecdsa.ecdsa.point_is_valid(curve.generator, x, y):
                raise ValidationFailure('invalid ECDSA key')
            point = ecdsa.ellipticcurve.Point(curve.curve, x, y, curve.order)
            verifying_key = ecdsa.keys.VerifyingKey.from_public_point(point,
                                                                      curve)
            pubkey = ECKeyWrapper(verifying_key, key_len)
            r = rrsig.signature[:key_len]
            s = rrsig.signature[key_len:]
            sig = ecdsa.ecdsa.Signature(Crypto.Util.number.bytes_to_long(r),
                                        Crypto.Util.number.bytes_to_long(s))
        else:
            raise ValidationFailure('unknown algorithm %u' % rrsig.algorithm)

        hash.update(_to_rdata(rrsig, origin)[:18])
        hash.update(rrsig.signer.to_digestable(origin))

        if rrsig.labels < len(rrname) - 1:
            suffix = rrname.split(rrsig.labels + 1)[1]
            rrname = dns.name.from_text('*', suffix)
        rrnamebuf = rrname.to_digestable(origin)
        rrfixed = struct.pack('!HHI', rdataset.rdtype, rdataset.rdclass,
                              rrsig.original_ttl)
        rrlist = sorted(rdataset)
        for rr in rrlist:
            hash.update(rrnamebuf)
            hash.update(rrfixed)
            rrdata = rr.to_digestable(origin)
            rrlen = struct.pack('!H', len(rrdata))
            hash.update(rrlen)
            hash.update(rrdata)

        digest = hash.digest()

        if _is_rsa(rrsig.algorithm):
            # PKCS1 algorithm identifier goop
            digest = _make_algorithm_id(rrsig.algorithm) + digest
            padlen = keylen // 8 - len(digest) - 3
            digest = struct.pack('!%dB' % (2 + padlen + 1),
                                 *([0, 1] + [0xFF] * padlen + [0])) + digest
        elif _is_dsa(rrsig.algorithm) or _is_ecdsa(rrsig.algorithm):
            pass
        else:
            # Raise here for code clarity; this won't actually ever happen
            # since if the algorithm is really unknown we'd already have
            # raised an exception above
            raise ValidationFailure('unknown algorithm %u' % rrsig.algorithm)

        if pubkey.verify(digest, sig):
            return
    raise ValidationFailure('verify failure')
예제 #6
0
파일: dnssec.py 프로젝트: CheneyHsu/PTest
def _validate_rrsig(rrset, rrsig, keys, origin=None, now=None):
    """Validate an RRset against a single signature rdata

    The owner name of the rrsig is assumed to be the same as the owner name
    of the rrset.

    @param rrset: The RRset to validate
    @type rrset: dns.rrset.RRset or (dns.name.Name, dns.rdataset.Rdataset)
    tuple
    @param rrsig: The signature rdata
    @type rrsig: dns.rrset.Rdata
    @param keys: The key dictionary.
    @type keys: a dictionary keyed by dns.name.Name with node or rdataset values
    @param origin: The origin to use for relative names
    @type origin: dns.name.Name or None
    @param now: The time to use when validating the signatures.  The default
    is the current time.
    @type now: int
    """

    if isinstance(origin, (str, unicode)):
        origin = dns.name.from_text(origin, dns.name.root)

    for candidate_key in _find_candidate_keys(keys, rrsig):
        if not candidate_key:
            raise ValidationFailure, 'unknown key'

        # For convenience, allow the rrset to be specified as a (name, rdataset)
        # tuple as well as a proper rrset
        if isinstance(rrset, tuple):
            rrname = rrset[0]
            rdataset = rrset[1]
        else:
            rrname = rrset.name
            rdataset = rrset

        if now is None:
            now = time.time()
        if rrsig.expiration < now:
            raise ValidationFailure, 'expired'
        if rrsig.inception > now:
            raise ValidationFailure, 'not yet valid'

        hash = _make_hash(rrsig.algorithm)

        if _is_rsa(rrsig.algorithm):
            keyptr = candidate_key.key
            (bytes,) = struct.unpack('!B', keyptr[0:1])
            keyptr = keyptr[1:]
            if bytes == 0:
                (bytes,) = struct.unpack('!H', keyptr[0:2])
                keyptr = keyptr[2:]
            rsa_e = keyptr[0:bytes]
            rsa_n = keyptr[bytes:]
            keylen = len(rsa_n) * 8
            pubkey = Crypto.PublicKey.RSA.construct(
                (Crypto.Util.number.bytes_to_long(rsa_n),
                 Crypto.Util.number.bytes_to_long(rsa_e)))
            sig = (Crypto.Util.number.bytes_to_long(rrsig.signature),)
        elif _is_dsa(rrsig.algorithm):
            keyptr = candidate_key.key
            (t,) = struct.unpack('!B', keyptr[0:1])
            keyptr = keyptr[1:]
            octets = 64 + t * 8
            dsa_q = keyptr[0:20]
            keyptr = keyptr[20:]
            dsa_p = keyptr[0:octets]
            keyptr = keyptr[octets:]
            dsa_g = keyptr[0:octets]
            keyptr = keyptr[octets:]
            dsa_y = keyptr[0:octets]
            pubkey = Crypto.PublicKey.DSA.construct(
                (Crypto.Util.number.bytes_to_long(dsa_y),
                 Crypto.Util.number.bytes_to_long(dsa_g),
                 Crypto.Util.number.bytes_to_long(dsa_p),
                 Crypto.Util.number.bytes_to_long(dsa_q)))
            (dsa_r, dsa_s) = struct.unpack('!20s20s', rrsig.signature[1:])
            sig = (Crypto.Util.number.bytes_to_long(dsa_r),
                   Crypto.Util.number.bytes_to_long(dsa_s))
        elif _is_ecdsa(rrsig.algorithm):
            if rrsig.algorithm == ECDSAP256SHA256:
                curve = ecdsa.curves.NIST256p
                key_len = 32
                digest_len = 32
            elif rrsig.algorithm == ECDSAP384SHA384:
                curve = ecdsa.curves.NIST384p
                key_len = 48
                digest_len = 48
            else:
                # shouldn't happen
                raise ValidationFailure, 'unknown ECDSA curve'
            keyptr = candidate_key.key
            x = Crypto.Util.number.bytes_to_long(keyptr[0:key_len])
            y = Crypto.Util.number.bytes_to_long(keyptr[key_len:key_len * 2])
            assert ecdsa.ecdsa.point_is_valid(curve.generator, x, y)
            point = ecdsa.ellipticcurve.Point(curve.curve, x, y, curve.order)
            verifying_key = ecdsa.keys.VerifyingKey.from_public_point(point,
                                                                      curve)
            pubkey = ECKeyWrapper(verifying_key, key_len)
            r = rrsig.signature[:key_len]
            s = rrsig.signature[key_len:]
            sig = ecdsa.ecdsa.Signature(Crypto.Util.number.bytes_to_long(r),
                                        Crypto.Util.number.bytes_to_long(s))
        else:
            raise ValidationFailure, 'unknown algorithm %u' % rrsig.algorithm

        hash.update(_to_rdata(rrsig, origin)[:18])
        hash.update(rrsig.signer.to_digestable(origin))

        if rrsig.labels < len(rrname) - 1:
            suffix = rrname.split(rrsig.labels + 1)[1]
            rrname = dns.name.from_text('*', suffix)
        rrnamebuf = rrname.to_digestable(origin)
        rrfixed = struct.pack('!HHI', rdataset.rdtype, rdataset.rdclass,
                              rrsig.original_ttl)
        rrlist = sorted(rdataset);
        for rr in rrlist:
            hash.update(rrnamebuf)
            hash.update(rrfixed)
            rrdata = rr.to_digestable(origin)
            rrlen = struct.pack('!H', len(rrdata))
            hash.update(rrlen)
            hash.update(rrdata)

        digest = hash.digest()

        if _is_rsa(rrsig.algorithm):
            # PKCS1 algorithm identifier goop
            digest = _make_algorithm_id(rrsig.algorithm) + digest
            padlen = keylen // 8 - len(digest) - 3
            digest = chr(0) + chr(1) + chr(0xFF) * padlen + chr(0) + digest
        elif _is_dsa(rrsig.algorithm) or _is_ecdsa(rrsig.algorithm):
            pass
        else:
            # Raise here for code clarity; this won't actually ever happen
            # since if the algorithm is really unknown we'd already have
            # raised an exception above
            raise ValidationFailure, 'unknown algorithm %u' % rrsig.algorithm

        if pubkey.verify(digest, sig):
            return
    raise ValidationFailure, 'verify failure'
예제 #7
0
파일: dnssec.py 프로젝트: webshell520/llk
def _validate_rrsig(rrset, rrsig, keys, origin=None, now=None):
    """Validate an RRset against a single signature rdata

    The owner name of the rrsig is assumed to be the same as the owner name
    of the rrset.

    @param rrset: The RRset to validate
    @type rrset: dns.rrset.RRset or (dns.name.Name, dns.rdataset.Rdataset)
    tuple
    @param rrsig: The signature rdata
    @type rrsig: dns.rrset.Rdata
    @param keys: The key dictionary.
    @type keys: a dictionary keyed by dns.name.Name with node or rdataset values
    @param origin: The origin to use for relative names
    @type origin: dns.name.Name or None
    @param now: The time to use when validating the signatures.  The default
    is the current time.
    @type now: int
    """

    if isinstance(origin, (str, unicode)):
        origin = dns.name.from_text(origin, dns.name.root)

    for candidate_key in _find_candidate_keys(keys, rrsig):
        if not candidate_key:
            raise ValidationFailure, 'unknown key'

        # For convenience, allow the rrset to be specified as a (name, rdataset)
        # tuple as well as a proper rrset
        if isinstance(rrset, tuple):
            rrname = rrset[0]
            rdataset = rrset[1]
        else:
            rrname = rrset.name
            rdataset = rrset

        if now is None:
            now = time.time()
        if rrsig.expiration < now:
            raise ValidationFailure, 'expired'
        if rrsig.inception > now:
            raise ValidationFailure, 'not yet valid'

        hash = _make_hash(rrsig.algorithm)

        if _is_rsa(rrsig.algorithm):
            keyptr = candidate_key.key
            (bytes,) = struct.unpack('!B', keyptr[0:1])
            keyptr = keyptr[1:]
            if bytes == 0:
                (bytes,) = struct.unpack('!H', keyptr[0:2])
                keyptr = keyptr[2:]
            rsa_e = keyptr[0:bytes]
            rsa_n = keyptr[bytes:]
            keylen = len(rsa_n) * 8
            pubkey = Crypto.PublicKey.RSA.construct(
                (Crypto.Util.number.bytes_to_long(rsa_n),
                 Crypto.Util.number.bytes_to_long(rsa_e)))
            sig = (Crypto.Util.number.bytes_to_long(rrsig.signature),)
        elif _is_dsa(rrsig.algorithm):
            keyptr = candidate_key.key
            (t,) = struct.unpack('!B', keyptr[0:1])
            keyptr = keyptr[1:]
            octets = 64 + t * 8
            dsa_q = keyptr[0:20]
            keyptr = keyptr[20:]
            dsa_p = keyptr[0:octets]
            keyptr = keyptr[octets:]
            dsa_g = keyptr[0:octets]
            keyptr = keyptr[octets:]
            dsa_y = keyptr[0:octets]
            pubkey = Crypto.PublicKey.DSA.construct(
                (Crypto.Util.number.bytes_to_long(dsa_y),
                 Crypto.Util.number.bytes_to_long(dsa_g),
                 Crypto.Util.number.bytes_to_long(dsa_p),
                 Crypto.Util.number.bytes_to_long(dsa_q)))
            (dsa_r, dsa_s) = struct.unpack('!20s20s', rrsig.signature[1:])
            sig = (Crypto.Util.number.bytes_to_long(dsa_r),
                   Crypto.Util.number.bytes_to_long(dsa_s))
        else:
            raise ValidationFailure, 'unknown algorithm %u' % rrsig.algorithm

        hash.update(_to_rdata(rrsig, origin)[:18])
        hash.update(rrsig.signer.to_digestable(origin))

        if rrsig.labels < len(rrname) - 1:
            suffix = rrname.split(rrsig.labels + 1)[1]
            rrname = dns.name.from_text('*', suffix)
        rrnamebuf = rrname.to_digestable(origin)
        rrfixed = struct.pack('!HHI', rdataset.rdtype, rdataset.rdclass,
                              rrsig.original_ttl)
        rrlist = sorted(rdataset);
        for rr in rrlist:
            hash.update(rrnamebuf)
            hash.update(rrfixed)
            rrdata = rr.to_digestable(origin)
            rrlen = struct.pack('!H', len(rrdata))
            hash.update(rrlen)
            hash.update(rrdata)

        digest = hash.digest()

        if _is_rsa(rrsig.algorithm):
            # PKCS1 algorithm identifier goop
            digest = _make_algorithm_id(rrsig.algorithm) + digest
            padlen = keylen // 8 - len(digest) - 3
            digest = chr(0) + chr(1) + chr(0xFF) * padlen + chr(0) + digest
        elif _is_dsa(rrsig.algorithm):
            pass
        else:
            # Raise here for code clarity; this won't actually ever happen
            # since if the algorithm is really unknown we'd already have
            # raised an exception above
            raise ValidationFailure, 'unknown algorithm %u' % rrsig.algorithm

        if pubkey.verify(digest, sig):
            return
    raise ValidationFailure, 'verify failure'
예제 #8
0
def _validate_rrsig(rrset, rrsig, keys, origin=None, now=None):
    """Validate an RRset against a single signature rdata

    The owner name of *rrsig* is assumed to be the same as the owner name
    of *rrset*.

    *rrset* is the RRset to validate.  It can be a ``dns.rrset.RRset`` or
    a ``(dns.name.Name, dns.rdataset.Rdataset)`` tuple.

    *rrsig* is a ``dns.rrset.Rdata``, the signature to validate.

    *keys* is the key dictionary, used to find the DNSKEY associated with
    a given name.  The dictionary is keyed by a ``dns.name.Name``, and has
    ``dns.node.Node`` or ``dns.rdataset.Rdataset`` values.

    *origin* is a ``dns.name.Name``, the origin to use for relative names.

    *now* is an ``int``, the time to use when validating the signatures,
    in seconds since the UNIX epoch.  The default is the current time.
    """

    if isinstance(origin, string_types):
        origin = dns.name.from_text(origin, dns.name.root)

    for candidate_key in _find_candidate_keys(keys, rrsig):
        if not candidate_key:
            raise ValidationFailure('unknown key')

        # For convenience, allow the rrset to be specified as a (name,
        # rdataset) tuple as well as a proper rrset
        if isinstance(rrset, tuple):
            rrname = rrset[0]
            rdataset = rrset[1]
        else:
            rrname = rrset.name
            rdataset = rrset

        if now is None:
            now = time.time()
        if rrsig.expiration < now:
            raise ValidationFailure('expired')
        if rrsig.inception > now:
            raise ValidationFailure('not yet valid')

        hash = _make_hash(rrsig.algorithm)

        if _is_rsa(rrsig.algorithm):
            keyptr = candidate_key.key
            (bytes_, ) = struct.unpack('!B', keyptr[0:1])
            keyptr = keyptr[1:]
            if bytes_ == 0:
                (bytes_, ) = struct.unpack('!H', keyptr[0:2])
                keyptr = keyptr[2:]
            rsa_e = keyptr[0:bytes_]
            rsa_n = keyptr[bytes_:]
            keylen = len(rsa_n) * 8
            pubkey = Crypto.PublicKey.RSA.construct(
                (Crypto.Util.number.bytes_to_long(rsa_n),
                 Crypto.Util.number.bytes_to_long(rsa_e)))
            sig = (Crypto.Util.number.bytes_to_long(rrsig.signature), )
        elif _is_dsa(rrsig.algorithm):
            keyptr = candidate_key.key
            (t, ) = struct.unpack('!B', keyptr[0:1])
            keyptr = keyptr[1:]
            octets = 64 + t * 8
            dsa_q = keyptr[0:20]
            keyptr = keyptr[20:]
            dsa_p = keyptr[0:octets]
            keyptr = keyptr[octets:]
            dsa_g = keyptr[0:octets]
            keyptr = keyptr[octets:]
            dsa_y = keyptr[0:octets]
            pubkey = Crypto.PublicKey.DSA.construct(
                (Crypto.Util.number.bytes_to_long(dsa_y),
                 Crypto.Util.number.bytes_to_long(dsa_g),
                 Crypto.Util.number.bytes_to_long(dsa_p),
                 Crypto.Util.number.bytes_to_long(dsa_q)))
            (dsa_r, dsa_s) = struct.unpack('!20s20s', rrsig.signature[1:])
            sig = (Crypto.Util.number.bytes_to_long(dsa_r),
                   Crypto.Util.number.bytes_to_long(dsa_s))
        elif _is_ecdsa(rrsig.algorithm):
            if rrsig.algorithm == ECDSAP256SHA256:
                curve = ecdsa.curves.NIST256p
                key_len = 32
            elif rrsig.algorithm == ECDSAP384SHA384:
                curve = ecdsa.curves.NIST384p
                key_len = 48
            else:
                # shouldn't happen
                raise ValidationFailure('unknown ECDSA curve')
            keyptr = candidate_key.key
            x = Crypto.Util.number.bytes_to_long(keyptr[0:key_len])
            y = Crypto.Util.number.bytes_to_long(keyptr[key_len:key_len * 2])
            assert ecdsa.ecdsa.point_is_valid(curve.generator, x, y)
            point = ecdsa.ellipticcurve.Point(curve.curve, x, y, curve.order)
            verifying_key = ecdsa.keys.VerifyingKey.from_public_point(
                point, curve)
            pubkey = ECKeyWrapper(verifying_key, key_len)
            r = rrsig.signature[:key_len]
            s = rrsig.signature[key_len:]
            sig = ecdsa.ecdsa.Signature(Crypto.Util.number.bytes_to_long(r),
                                        Crypto.Util.number.bytes_to_long(s))
        else:
            raise ValidationFailure('unknown algorithm %u' % rrsig.algorithm)

        hash.update(_to_rdata(rrsig, origin)[:18])
        hash.update(rrsig.signer.to_digestable(origin))

        if rrsig.labels < len(rrname) - 1:
            suffix = rrname.split(rrsig.labels + 1)[1]
            rrname = dns.name.from_text('*', suffix)
        rrnamebuf = rrname.to_digestable(origin)
        rrfixed = struct.pack('!HHI', rdataset.rdtype, rdataset.rdclass,
                              rrsig.original_ttl)
        rrlist = sorted(rdataset)
        for rr in rrlist:
            hash.update(rrnamebuf)
            hash.update(rrfixed)
            rrdata = rr.to_digestable(origin)
            rrlen = struct.pack('!H', len(rrdata))
            hash.update(rrlen)
            hash.update(rrdata)

        digest = hash.digest()

        if _is_rsa(rrsig.algorithm):
            # PKCS1 algorithm identifier goop
            digest = _make_algorithm_id(rrsig.algorithm) + digest
            padlen = keylen // 8 - len(digest) - 3
            digest = struct.pack('!%dB' % (2 + padlen + 1),
                                 *([0, 1] + [0xFF] * padlen + [0])) + digest
        elif _is_dsa(rrsig.algorithm) or _is_ecdsa(rrsig.algorithm):
            pass
        else:
            # Raise here for code clarity; this won't actually ever happen
            # since if the algorithm is really unknown we'd already have
            # raised an exception above
            raise ValidationFailure('unknown algorithm %u' % rrsig.algorithm)

        if pubkey.verify(digest, sig):
            return
    raise ValidationFailure('verify failure')
예제 #9
0
def _validate_rrsig(rrset, rrsig, keys, origin=None, now=None):
    """Validate an RRset against a single signature rdata

    The owner name of the rrsig is assumed to be the same as the owner name
    of the rrset.

    @param rrset: The RRset to validate
    @type rrset: dns.rrset.RRset or (dns.name.Name, dns.rdataset.Rdataset)
    tuple
    @param rrsig: The signature rdata
    @type rrsig: dns.rrset.Rdata
    @param keys: The key dictionary.
    @type keys: a dictionary keyed by dns.name.Name with node or rdataset values
    @param origin: The origin to use for relative names
    @type origin: dns.name.Name or None
    @param now: The time to use when validating the signatures.  The default
    is the current time.
    @type now: int
    """

    if isinstance(origin, str):
        origin = dns.name.from_text(origin, dns.name.root)

    for candidate_key in _find_candidate_keys(keys, rrsig):
        if not candidate_key:
            raise ValidationFailure('unknown key')

        # For convenience, allow the rrset to be specified as a (name, rdataset)
        # tuple as well as a proper rrset
        if isinstance(rrset, tuple):
            rrname = rrset[0]
            rdataset = rrset[1]
        else:
            rrname = rrset.name
            rdataset = rrset

        if now is None:
            now = time.time()
        if rrsig.expiration < now:
            raise ValidationFailure('expired')
        if rrsig.inception > now:
            raise ValidationFailure('not yet valid')

        hash = _make_hash(rrsig.algorithm)

        if _is_rsa(rrsig.algorithm):
            keyptr = candidate_key.key
            (count,) = struct.unpack('!B', keyptr[0:1])
            keyptr = keyptr[1:]
            if count == 0:
                (count,) = struct.unpack('!H', keyptr[0:2])
                keyptr = keyptr[2:]
            rsa_e = keyptr[0:count]
            rsa_n = keyptr[count:]
            keylen = len(rsa_n) * 8
            pubkey = Crypto.PublicKey.RSA.construct(
                (Crypto.Util.number.bytes_to_long(rsa_n),
                 Crypto.Util.number.bytes_to_long(rsa_e)))
            sig = (Crypto.Util.number.bytes_to_long(rrsig.signature),)
        elif _is_dsa(rrsig.algorithm):
            keyptr = candidate_key.key
            (t,) = struct.unpack('!B', keyptr[0:1])
            keyptr = keyptr[1:]
            octets = 64 + t * 8
            dsa_q = keyptr[0:20]
            keyptr = keyptr[20:]
            dsa_p = keyptr[0:octets]
            keyptr = keyptr[octets:]
            dsa_g = keyptr[0:octets]
            keyptr = keyptr[octets:]
            dsa_y = keyptr[0:octets]
            pubkey = Crypto.PublicKey.DSA.construct(
                (Crypto.Util.number.bytes_to_long(dsa_y),
                 Crypto.Util.number.bytes_to_long(dsa_g),
                 Crypto.Util.number.bytes_to_long(dsa_p),
                 Crypto.Util.number.bytes_to_long(dsa_q)))
            (dsa_r, dsa_s) = struct.unpack('!20s20s', rrsig.signature[1:])
            sig = (Crypto.Util.number.bytes_to_long(dsa_r),
                   Crypto.Util.number.bytes_to_long(dsa_s))
        else:
            raise ValidationFailure('unknown algorithm %u' % rrsig.algorithm)

        hash.update(_to_rdata(rrsig, origin)[:18])
        hash.update(rrsig.signer.to_digestable(origin))

        if rrsig.labels < len(rrname) - 1:
            suffix = rrname.split(rrsig.labels + 1)[1]
            rrname = dns.name.from_text('*', suffix)
        rrnamebuf = rrname.to_digestable(origin)
        rrfixed = struct.pack('!HHI', rdataset.rdtype, rdataset.rdclass,
                              rrsig.original_ttl)
        rrlist = sorted(rdataset);
        for rr in rrlist:
            hash.update(rrnamebuf)
            hash.update(rrfixed)
            rrdata = rr.to_digestable(origin)
            rrlen = struct.pack('!H', len(rrdata))
            hash.update(rrlen)
            hash.update(rrdata)

        digest = hash.digest()

        if _is_rsa(rrsig.algorithm):
            # PKCS1 algorithm identifier goop
            digest = _make_algorithm_id(rrsig.algorithm) + digest
            padlen = keylen // 8 - len(digest) - 3
            digest = bytes([0]) + bytes([1]) + bytes([0xFF]) * padlen + \
                     bytes([0]) + digest
        elif _is_dsa(rrsig.algorithm):
            pass
        else:
            # Raise here for code clarity; this won't actually ever happen
            # since if the algorithm is really unknown we'd already have
            # raised an exception above
            raise ValidationFailure('unknown algorithm %u' % rrsig.algorithm)

        if pubkey.verify(digest, sig):
            return
    raise ValidationFailure('verify failure')