test/patches/scapy-2.4.3/ipsec.patch

   1 diff --git a/scapy/layers/ipsec.py b/scapy/layers/ipsec.py
   2 index ae057ee1..55d0dd53 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 @@ -359,11 +360,8 @@ class CryptAlgo(object):
  14              encryptor = cipher.encryptor()
  15
  16              if self.is_aead:
  17 -                if esn_en:
  18 -                    aad = struct.pack('!LLL', esp.spi, esn, esp.seq)
  19 -                else:
  20 -                    aad = struct.pack('!LL', esp.spi, esp.seq)
  21 -                encryptor.authenticate_additional_data(aad)
  22 +                encryptor.authenticate_additional_data(sa.build_aead(esp))
  23 +
  24                  data = encryptor.update(data) + encryptor.finalize()
  25                  data += encryptor.tag[:self.icv_size]
  26              else:
  27 @@ -400,12 +398,7 @@ class CryptAlgo(object):
  28
  29              if self.is_aead:
  30                  # Tag value check is done during the finalize method
  31 -                if esn_en:
  32 -                    decryptor.authenticate_additional_data(
  33 -                        struct.pack('!LLL', esp.spi, esn, esp.seq))
  34 -                else:
  35 -                    decryptor.authenticate_additional_data(
  36 -                        struct.pack('!LL', esp.spi, esp.seq))
  37 +                decryptor.authenticate_additional_data(sa.build_aead(esp))
  38              try:
  39                  data = decryptor.update(data) + decryptor.finalize()
  40              except InvalidTag as err:
  41 @@ -445,6 +438,7 @@ if algorithms:
  42      CRYPT_ALGOS['AES-CTR'] = CryptAlgo('AES-CTR',
  43                                         cipher=algorithms.AES,
  44                                         mode=modes.CTR,
  45 +                                       block_size=1,
  46                                         iv_size=8,
  47                                         salt_size=4,
  48                                         format_mode_iv=_aes_ctr_format_mode_iv)
  49 @@ -452,6 +446,7 @@ if algorithms:
  50      CRYPT_ALGOS['AES-GCM'] = CryptAlgo('AES-GCM',
  51                                         cipher=algorithms.AES,
  52                                         mode=modes.GCM,
  53 +                                       block_size=1,
  54                                         salt_size=4,
  55                                         iv_size=8,
  56                                         icv_size=16,
  57 @@ -460,6 +455,7 @@ if algorithms:
  58          CRYPT_ALGOS['AES-CCM'] = CryptAlgo('AES-CCM',
  59                                             cipher=algorithms.AES,
  60                                             mode=modes.CCM,
  61 +                                           block_size=1,
  62                                             iv_size=8,
  63                                             salt_size=3,
  64                                             icv_size=16,
  65 @@ -544,7 +540,7 @@ class AuthAlgo(object):
  66          else:
  67              return self.mac(key, self.digestmod(), default_backend())
  68
  69 -    def sign(self, pkt, key):
  70 +    def sign(self, pkt, key, trailer=None):
  71          """
  72          Sign an IPsec (ESP or AH) packet with this algo.
  73
  74 @@ -560,16 +556,20 @@ class AuthAlgo(object):
  75
  76          if pkt.haslayer(ESP):
  77              mac.update(raw(pkt[ESP]))
  78 +            if trailer:
  79 +                mac.update(trailer)
  80              pkt[ESP].data += mac.finalize()[:self.icv_size]
  81
  82          elif pkt.haslayer(AH):
  83              clone = zero_mutable_fields(pkt.copy(), sending=True)
  84              mac.update(raw(clone))
  85 +            if trailer:
  86 +                mac.update(trailer)
  87              pkt[AH].icv = mac.finalize()[:self.icv_size]
  88
  89          return pkt
  90
  91 -    def verify(self, pkt, key):
  92 +    def verify(self, pkt, key, trailer):
  93          """
  94          Check that the integrity check value (icv) of a packet is valid.
  95
  96 @@ -600,6 +600,8 @@ class AuthAlgo(object):
  97              clone = zero_mutable_fields(pkt.copy(), sending=False)
  98
  99          mac.update(raw(clone))
 100 +        if trailer:
 101 +            mac.update(trailer) # bytearray(4)) #raw(trailer))
 102          computed_icv = mac.finalize()[:self.icv_size]
 103
 104          # XXX: Cannot use mac.verify because the ICV can be truncated
 105 @@ -788,7 +790,7 @@ class SecurityAssociation(object):
 106      This class is responsible of "encryption" and "decryption" of IPsec packets.  # noqa: E501
 107      """
 108
 109 -    SUPPORTED_PROTOS = (IP, IPv6)
 110 +    SUPPORTED_PROTOS = (IP, IPv6, MPLS)
 111
 112      def __init__(self, proto, spi, seq_num=1, crypt_algo=None, crypt_key=None,
 113                   auth_algo=None, auth_key=None, tunnel_header=None, nat_t_header=None, esn_en=False, esn=0):   # noqa: E501
 114 @@ -862,6 +864,23 @@ class SecurityAssociation(object):
 115                  raise TypeError('nat_t_header must be %s' % UDP.name)
 116          self.nat_t_header = nat_t_header
 117
 118 +    def build_aead(self, esp):
 119 +        if self.esn_en:
 120 +            return (struct.pack('!LLL', esp.spi, self.seq_num >> 32, esp.seq))
 121 +        else:
 122 +            return (struct.pack('!LL', esp.spi, esp.seq))
 123 +
 124 +    def build_seq_num(self, num):
 125 +        # only lower order bits are  transmitted
 126 +        # higher order bits are used in the ICV
 127 +        lower = num & 0xffffffff
 128 +        upper = num >> 32
 129 +
 130 +        if self.esn_en:
 131 +            return lower, struct.pack("!I", upper)
 132 +        else:
 133 +            return lower, None
 134 +
 135      def check_spi(self, pkt):
 136          if pkt.spi != self.spi:
 137              raise TypeError('packet spi=0x%x does not match the SA spi=0x%x' %
 138 @@ -875,7 +894,8 @@ class SecurityAssociation(object):
 139              if len(iv) != self.crypt_algo.iv_size:
 140                  raise TypeError('iv length must be %s' % self.crypt_algo.iv_size)  # noqa: E501
 141
 142 -        esp = _ESPPlain(spi=self.spi, seq=seq_num or self.seq_num, iv=iv)
 143 +        low_seq_num, high_seq_num = self.build_seq_num(seq_num or self.seq_num)
 144 +        esp = _ESPPlain(spi=self.spi, seq=low_seq_num, iv=iv)
 145
 146          if self.tunnel_header:
 147              tunnel = self.tunnel_header.copy()
 148 @@ -899,7 +919,7 @@ class SecurityAssociation(object):
 149                                        esn_en=esn_en or self.esn_en,
 150                                        esn=esn or self.esn)
 151
 152 -        self.auth_algo.sign(esp, self.auth_key)
 153 +        self.auth_algo.sign(esp, self.auth_key, high_seq_num)
 154
 155          if self.nat_t_header:
 156              nat_t_header = self.nat_t_header.copy()
 157 @@ -926,7 +946,8 @@ class SecurityAssociation(object):
 158
 159      def _encrypt_ah(self, pkt, seq_num=None):
 160
 161 -        ah = AH(spi=self.spi, seq=seq_num or self.seq_num,
 162 +        low_seq_num, high_seq_num = self.build_seq_num(seq_num or self.seq_num)
 163 +        ah = AH(spi=self.spi, seq=low_seq_num,
 164                  icv=b"\x00" * self.auth_algo.icv_size)
 165
 166          if self.tunnel_header:
 167 @@ -966,7 +987,8 @@ class SecurityAssociation(object):
 168          else:
 169              ip_header.plen = len(ip_header.payload) + len(ah) + len(payload)
 170
 171 -        signed_pkt = self.auth_algo.sign(ip_header / ah / payload, self.auth_key)  # noqa: E501
 172 +        signed_pkt = self.auth_algo.sign(ip_header / ah / payload,
 173 +                                         self.auth_key, high_seq_num)  # noqa: E501
 174
 175          # sequence number must always change, unless specified by the user
 176          if seq_num is None:
 177 @@ -1003,11 +1025,12 @@ class SecurityAssociation(object):
 178
 179      def _decrypt_esp(self, pkt, verify=True, esn_en=None, esn=None):
 180
 181 +        low_seq_num, high_seq_num = self.build_seq_num(self.seq_num)
 182          encrypted = pkt[ESP]
 183
 184          if verify:
 185              self.check_spi(pkt)
 186 -            self.auth_algo.verify(encrypted, self.auth_key)
 187 +            self.auth_algo.verify(encrypted, self.auth_key, high_seq_num)
 188
 189          esp = self.crypt_algo.decrypt(self, encrypted, self.crypt_key,
 190                                        self.crypt_algo.icv_size or
 191 @@ -1048,9 +1071,10 @@ class SecurityAssociation(object):
 192
 193      def _decrypt_ah(self, pkt, verify=True):
 194
 195 +        low_seq_num, high_seq_num = self.build_seq_num(self.seq_num)
 196          if verify:
 197              self.check_spi(pkt)
 198 -            self.auth_algo.verify(pkt, self.auth_key)
 199 +            self.auth_algo.verify(pkt, self.auth_key, high_seq_num)
 200
 201          ah = pkt[AH]
 202          payload = ah.payload