test/patches/scapy-2.4.3/ipsec.patch

   1 diff --git a/scapy/layers/ipsec.py b/scapy/layers/ipsec.py
   2 index ae057ee1..d7a21e8b 100644
   3 --- a/scapy/layers/ipsec.py
   4 +++ b/scapy/layers/ipsec.py
   5 @@ -56,6 +56,7 @@ from scapy.fields import ByteEnumField, ByteField, IntField, PacketField, \
   6      ShortField, StrField, XIntField, XStrField, XStrLenField
   7  from scapy.packet import Packet, bind_layers, Raw
   8  from scapy.layers.inet import IP, UDP
   9 +from scapy.contrib.mpls import MPLS
  10  import scapy.modules.six as six
  11  from scapy.modules.six.moves import range
  12  from scapy.layers.inet6 import IPv6, IPv6ExtHdrHopByHop, IPv6ExtHdrDestOpt, \
  13 @@ -138,6 +139,7 @@ bind_layers(IP, ESP, proto=socket.IPPROTO_ESP)
  14  bind_layers(IPv6, ESP, nh=socket.IPPROTO_ESP)
  15  bind_layers(UDP, ESP, dport=4500)  # NAT-Traversal encapsulation
  16  bind_layers(UDP, ESP, sport=4500)  # NAT-Traversal encapsulation
  17 +bind_layers(UDP, ESP, dport=4545)  # NAT-Traversal encapsulation - random port
  18
  19  ###############################################################################
  20
  21 @@ -359,11 +361,8 @@ class CryptAlgo(object):
  22              encryptor = cipher.encryptor()
  23
  24              if self.is_aead:
  25 -                if esn_en:
  26 -                    aad = struct.pack('!LLL', esp.spi, esn, esp.seq)
  27 -                else:
  28 -                    aad = struct.pack('!LL', esp.spi, esp.seq)
  29 -                encryptor.authenticate_additional_data(aad)
  30 +                encryptor.authenticate_additional_data(sa.build_aead(esp))
  31 +
  32                  data = encryptor.update(data) + encryptor.finalize()
  33                  data += encryptor.tag[:self.icv_size]
  34              else:
  35 @@ -400,12 +399,7 @@ class CryptAlgo(object):
  36
  37              if self.is_aead:
  38                  # Tag value check is done during the finalize method
  39 -                if esn_en:
  40 -                    decryptor.authenticate_additional_data(
  41 -                        struct.pack('!LLL', esp.spi, esn, esp.seq))
  42 -                else:
  43 -                    decryptor.authenticate_additional_data(
  44 -                        struct.pack('!LL', esp.spi, esp.seq))
  45 +                decryptor.authenticate_additional_data(sa.build_aead(esp))
  46              try:
  47                  data = decryptor.update(data) + decryptor.finalize()
  48              except InvalidTag as err:
  49 @@ -445,6 +439,7 @@ if algorithms:
  50      CRYPT_ALGOS['AES-CTR'] = CryptAlgo('AES-CTR',
  51                                         cipher=algorithms.AES,
  52                                         mode=modes.CTR,
  53 +                                       block_size=1,
  54                                         iv_size=8,
  55                                         salt_size=4,
  56                                         format_mode_iv=_aes_ctr_format_mode_iv)
  57 @@ -452,6 +447,7 @@ if algorithms:
  58      CRYPT_ALGOS['AES-GCM'] = CryptAlgo('AES-GCM',
  59                                         cipher=algorithms.AES,
  60                                         mode=modes.GCM,
  61 +                                       block_size=1,
  62                                         salt_size=4,
  63                                         iv_size=8,
  64                                         icv_size=16,
  65 @@ -460,6 +456,7 @@ if algorithms:
  66          CRYPT_ALGOS['AES-CCM'] = CryptAlgo('AES-CCM',
  67                                             cipher=algorithms.AES,
  68                                             mode=modes.CCM,
  69 +                                           block_size=1,
  70                                             iv_size=8,
  71                                             salt_size=3,
  72                                             icv_size=16,
  73 @@ -544,7 +541,7 @@ class AuthAlgo(object):
  74          else:
  75              return self.mac(key, self.digestmod(), default_backend())
  76
  77 -    def sign(self, pkt, key):
  78 +    def sign(self, pkt, key, trailer=None):
  79          """
  80          Sign an IPsec (ESP or AH) packet with this algo.
  81
  82 @@ -560,16 +557,20 @@ class AuthAlgo(object):
  83
  84          if pkt.haslayer(ESP):
  85              mac.update(raw(pkt[ESP]))
  86 +            if trailer:
  87 +                mac.update(trailer)
  88              pkt[ESP].data += mac.finalize()[:self.icv_size]
  89
  90          elif pkt.haslayer(AH):
  91              clone = zero_mutable_fields(pkt.copy(), sending=True)
  92              mac.update(raw(clone))
  93 +            if trailer:
  94 +                mac.update(trailer)
  95              pkt[AH].icv = mac.finalize()[:self.icv_size]
  96
  97          return pkt
  98
  99 -    def verify(self, pkt, key):
 100 +    def verify(self, pkt, key, trailer):
 101          """
 102          Check that the integrity check value (icv) of a packet is valid.
 103
 104 @@ -600,6 +601,8 @@ class AuthAlgo(object):
 105              clone = zero_mutable_fields(pkt.copy(), sending=False)
 106
 107          mac.update(raw(clone))
 108 +        if trailer:
 109 +            mac.update(trailer) # bytearray(4)) #raw(trailer))
 110          computed_icv = mac.finalize()[:self.icv_size]
 111
 112          # XXX: Cannot use mac.verify because the ICV can be truncated
 113 @@ -788,7 +791,7 @@ class SecurityAssociation(object):
 114      This class is responsible of "encryption" and "decryption" of IPsec packets.  # noqa: E501
 115      """
 116
 117 -    SUPPORTED_PROTOS = (IP, IPv6)
 118 +    SUPPORTED_PROTOS = (IP, IPv6, MPLS)
 119
 120      def __init__(self, proto, spi, seq_num=1, crypt_algo=None, crypt_key=None,
 121                   auth_algo=None, auth_key=None, tunnel_header=None, nat_t_header=None, esn_en=False, esn=0):   # noqa: E501
 122 @@ -862,6 +865,23 @@ class SecurityAssociation(object):
 123                  raise TypeError('nat_t_header must be %s' % UDP.name)
 124          self.nat_t_header = nat_t_header
 125
 126 +    def build_aead(self, esp):
 127 +        if self.esn_en:
 128 +            return (struct.pack('!LLL', esp.spi, self.seq_num >> 32, esp.seq))
 129 +        else:
 130 +            return (struct.pack('!LL', esp.spi, esp.seq))
 131 +
 132 +    def build_seq_num(self, num):
 133 +        # only lower order bits are  transmitted
 134 +        # higher order bits are used in the ICV
 135 +        lower = num & 0xffffffff
 136 +        upper = num >> 32
 137 +
 138 +        if self.esn_en:
 139 +            return lower, struct.pack("!I", upper)
 140 +        else:
 141 +            return lower, None
 142 +
 143      def check_spi(self, pkt):
 144          if pkt.spi != self.spi:
 145              raise TypeError('packet spi=0x%x does not match the SA spi=0x%x' %
 146 @@ -875,7 +895,8 @@ class SecurityAssociation(object):
 147              if len(iv) != self.crypt_algo.iv_size:
 148                  raise TypeError('iv length must be %s' % self.crypt_algo.iv_size)  # noqa: E501
 149
 150 -        esp = _ESPPlain(spi=self.spi, seq=seq_num or self.seq_num, iv=iv)
 151 +        low_seq_num, high_seq_num = self.build_seq_num(seq_num or self.seq_num)
 152 +        esp = _ESPPlain(spi=self.spi, seq=low_seq_num, iv=iv)
 153
 154          if self.tunnel_header:
 155              tunnel = self.tunnel_header.copy()
 156 @@ -899,7 +920,7 @@ class SecurityAssociation(object):
 157                                        esn_en=esn_en or self.esn_en,
 158                                        esn=esn or self.esn)
 159
 160 -        self.auth_algo.sign(esp, self.auth_key)
 161 +        self.auth_algo.sign(esp, self.auth_key, high_seq_num)
 162
 163          if self.nat_t_header:
 164              nat_t_header = self.nat_t_header.copy()
 165 @@ -926,7 +947,8 @@ class SecurityAssociation(object):
 166
 167      def _encrypt_ah(self, pkt, seq_num=None):
 168
 169 -        ah = AH(spi=self.spi, seq=seq_num or self.seq_num,
 170 +        low_seq_num, high_seq_num = self.build_seq_num(seq_num or self.seq_num)
 171 +        ah = AH(spi=self.spi, seq=low_seq_num,
 172                  icv=b"\x00" * self.auth_algo.icv_size)
 173
 174          if self.tunnel_header:
 175 @@ -966,7 +988,8 @@ class SecurityAssociation(object):
 176          else:
 177              ip_header.plen = len(ip_header.payload) + len(ah) + len(payload)
 178
 179 -        signed_pkt = self.auth_algo.sign(ip_header / ah / payload, self.auth_key)  # noqa: E501
 180 +        signed_pkt = self.auth_algo.sign(ip_header / ah / payload,
 181 +                                         self.auth_key, high_seq_num)  # noqa: E501
 182
 183          # sequence number must always change, unless specified by the user
 184          if seq_num is None:
 185 @@ -1003,11 +1026,12 @@ class SecurityAssociation(object):
 186
 187      def _decrypt_esp(self, pkt, verify=True, esn_en=None, esn=None):
 188
 189 +        low_seq_num, high_seq_num = self.build_seq_num(self.seq_num)
 190          encrypted = pkt[ESP]
 191
 192          if verify:
 193              self.check_spi(pkt)
 194 -            self.auth_algo.verify(encrypted, self.auth_key)
 195 +            self.auth_algo.verify(encrypted, self.auth_key, high_seq_num)
 196
 197          esp = self.crypt_algo.decrypt(self, encrypted, self.crypt_key,
 198                                        self.crypt_algo.icv_size or
 199 @@ -1048,9 +1072,10 @@ class SecurityAssociation(object):
 200
 201      def _decrypt_ah(self, pkt, verify=True):
 202
 203 +        low_seq_num, high_seq_num = self.build_seq_num(self.seq_num)
 204          if verify:
 205              self.check_spi(pkt)
 206 -            self.auth_algo.verify(pkt, self.auth_key)
 207 +            self.auth_algo.verify(pkt, self.auth_key, high_seq_num)
 208
 209          ah = pkt[AH]
 210          payload = ah.payload