IPSEC tests fnd fix or Extended Sequence Numbers

Change-Id: Iad6c4b867961ec8036110a4e15a829ddb93193ed
Signed-off-by: Neale Ranns <nranns@cisco.com>

3 files changed, 264 insertions, 29 deletions

diff --git a/test/patches/scapy-2.4/ipsec.patch b/test/patches/scapy-2.4/ipsec.patch
new file mode 100644
index 00000000000..5a644327596
--- /dev/null
+++ b/test/patches/scapy-2.4/ipsec.patch
@@ -0,0 +1,156 @@
+diff --git a/scapy/layers/ipsec.py b/scapy/layers/ipsec.py
+index 69e7ae3b..99373466 100644
+--- a/scapy/layers/ipsec.py
++++ b/scapy/layers/ipsec.py
+@@ -518,12 +517,16 @@ class AuthAlgo(object):
+         else:
+             return self.mac(key, self.digestmod(), default_backend())
+ 
+-    def sign(self, pkt, key):
++    def sign(self, pkt, key, trailer=None):
+         """
+         Sign an IPsec (ESP or AH) packet with this algo.
+ 
+         @param pkt:    a packet that contains a valid encrypted ESP or AH layer
+         @param key:    the authentication key, a byte string
++        @param trailer: additional data appended to the packet for ICV
++                        calculation, but not trnasmitted with the packet.
++                        For example, the high order bits of the exteneded
++                        sequence number.
+ 
+         @return: the signed packet
+         """
+@@ -539,11 +542,13 @@ class AuthAlgo(object):
+         elif pkt.haslayer(AH):
+             clone = zero_mutable_fields(pkt.copy(), sending=True)
+             mac.update(raw(clone))
++            if trailer:
++                mac.update(trailer)
+             pkt[AH].icv = mac.finalize()[:self.icv_size]
+ 
+         return pkt
+ 
+-    def verify(self, pkt, key):
++    def verify(self, pkt, key, trailer):
+         """
+         Check that the integrity check value (icv) of a packet is valid.
+ 
+@@ -574,6 +579,8 @@ class AuthAlgo(object):
+             clone = zero_mutable_fields(pkt.copy(), sending=False)
+ 
+         mac.update(raw(clone))
++        if trailer:
++            mac.update(trailer) # bytearray(4)) #raw(trailer))
+         computed_icv = mac.finalize()[:self.icv_size]
+ 
+         # XXX: Cannot use mac.verify because the ICV can be truncated
+@@ -757,7 +764,8 @@ class SecurityAssociation(object):
+     SUPPORTED_PROTOS = (IP, IPv6)
+ 
+     def __init__(self, proto, spi, seq_num=1, crypt_algo=None, crypt_key=None,
+-                 auth_algo=None, auth_key=None, tunnel_header=None, nat_t_header=None):
++                 auth_algo=None, auth_key=None, tunnel_header=None, nat_t_header=None,
++                 use_esn=False):
+         """
+         @param proto: the IPsec proto to use (ESP or AH)
+         @param spi: the Security Parameters Index of this SA
+@@ -771,6 +779,7 @@ class SecurityAssociation(object):
+                               to encapsulate the encrypted packets.
+         @param nat_t_header: an instance of a UDP header that will be used
+                              for NAT-Traversal.
++        @param use_esn: Use Extended Sequence Numbers
+         """
+ 
+         if proto not in (ESP, AH, ESP.name, AH.name):
+@@ -782,6 +791,7 @@ class SecurityAssociation(object):
+ 
+         self.spi = spi
+         self.seq_num = seq_num
++        self.use_esn = use_esn
+ 
+         if crypt_algo:
+             if crypt_algo not in CRYPT_ALGOS:
+@@ -827,6 +837,17 @@ class SecurityAssociation(object):
+             raise TypeError('packet spi=0x%x does not match the SA spi=0x%x' %
+                             (pkt.spi, self.spi))
+ 
++    def build_seq_num(self, num):
++        # only lower order bits are  transmitted
++        # higher order bits are used in the ICV
++        lower = num & 0xffffffff
++        upper = num >> 32
++
++        if self.use_esn:
++            return lower, struct.pack(">I", upper)
++        else:
++            return lower, None
++
+     def _encrypt_esp(self, pkt, seq_num=None, iv=None):
+ 
+         if iv is None:
+@@ -835,7 +856,8 @@ class SecurityAssociation(object):
+             if len(iv) != self.crypt_algo.iv_size:
+                 raise TypeError('iv length must be %s' % self.crypt_algo.iv_size)
+ 
+-        esp = _ESPPlain(spi=self.spi, seq=seq_num or self.seq_num, iv=iv)
++        low_seq_num, high_seq_num = self.build_seq_num(seq_num or self.seq_num)
++        esp = _ESPPlain(spi=self.spi, seq=low_seq_num, iv=iv)
+ 
+         if self.tunnel_header:
+             tunnel = self.tunnel_header.copy()
+@@ -857,7 +879,7 @@ class SecurityAssociation(object):
+         esp = self.crypt_algo.pad(esp)
+         esp = self.crypt_algo.encrypt(self, esp, self.crypt_key)
+ 
+-        self.auth_algo.sign(esp, self.auth_key)
++        self.auth_algo.sign(esp, self.auth_key, high_seq_num)
+ 
+         if self.nat_t_header:
+             nat_t_header = self.nat_t_header.copy()
+@@ -884,7 +906,8 @@ class SecurityAssociation(object):
+ 
+     def _encrypt_ah(self, pkt, seq_num=None):
+ 
+-        ah = AH(spi=self.spi, seq=seq_num or self.seq_num,
++        low_seq_num, high_seq_num = self.build_seq_num(seq_num or self.seq_num)
++        ah = AH(spi=self.spi, seq=low_seq_num,
+                 icv = b"\x00" * self.auth_algo.icv_size)
+ 
+         if self.tunnel_header:
+@@ -924,7 +947,8 @@ class SecurityAssociation(object):
+         else:
+             ip_header.plen = len(ip_header.payload) + len(ah) + len(payload)
+ 
+-        signed_pkt = self.auth_algo.sign(ip_header / ah / payload, self.auth_key)
++        signed_pkt = self.auth_algo.sign(ip_header / ah / payload,
++                                         self.auth_key, high_seq_num)
+ 
+         # sequence number must always change, unless specified by the user
+         if seq_num is None:
+@@ -955,11 +979,12 @@ class SecurityAssociation(object):
+ 
+     def _decrypt_esp(self, pkt, verify=True):
+ 
++        low_seq_num, high_seq_num = self.build_seq_num(self.seq_num)
+         encrypted = pkt[ESP]
+ 
+         if verify:
+             self.check_spi(pkt)
+-            self.auth_algo.verify(encrypted, self.auth_key)
++            self.auth_algo.verify(encrypted, self.auth_key, high_seq_num)
+ 
+         esp = self.crypt_algo.decrypt(self, encrypted, self.crypt_key,
+                                       self.crypt_algo.icv_size or
+@@ -998,9 +1023,11 @@ class SecurityAssociation(object):
+ 
+     def _decrypt_ah(self, pkt, verify=True):
+ 
++        low_seq_num, high_seq_num = self.build_seq_num(self.seq_num)
++
+         if verify:
+             self.check_spi(pkt)
+-            self.auth_algo.verify(pkt, self.auth_key)
++            self.auth_algo.verify(pkt, self.auth_key, high_seq_num)
+ 
+         ah = pkt[AH]
+         payload = ah.payload
diff --git a/test/template_ipsec.py b/test/template_ipsec.py
index 78d75844d5d..273865d407c 100644
--- a/test/template_ipsec.py
+++ b/test/template_ipsec.py
@@ -81,6 +81,8 @@ class IPsecIPv6Params(object):
 
 def config_tun_params(p, encryption_type, tun_if):
     ip_class_by_addr_type = {socket.AF_INET: IP, socket.AF_INET6: IPv6}
+    use_esn = bool(p.flags & (VppEnum.vl_api_ipsec_sad_flags_t.
+                              IPSEC_API_SAD_FLAG_USE_EXTENDED_SEQ_NUM))
     p.scapy_tun_sa = SecurityAssociation(
         encryption_type, spi=p.vpp_tun_spi,
         crypt_algo=p.crypt_algo, crypt_key=p.crypt_key,
@@ -88,7 +90,8 @@ def config_tun_params(p, encryption_type, tun_if):
         tunnel_header=ip_class_by_addr_type[p.addr_type](
             src=tun_if.remote_addr[p.addr_type],
             dst=tun_if.local_addr[p.addr_type]),
-        nat_t_header=p.nat_header)
+        nat_t_header=p.nat_header,
+        use_esn=use_esn)
     p.vpp_tun_sa = SecurityAssociation(
         encryption_type, spi=p.scapy_tun_spi,
         crypt_algo=p.crypt_algo, crypt_key=p.crypt_key,
@@ -96,10 +99,13 @@ def config_tun_params(p, encryption_type, tun_if):
         tunnel_header=ip_class_by_addr_type[p.addr_type](
             dst=tun_if.remote_addr[p.addr_type],
             src=tun_if.local_addr[p.addr_type]),
-        nat_t_header=p.nat_header)
+        nat_t_header=p.nat_header,
+        use_esn=use_esn)
 
 
 def config_tra_params(p, encryption_type):
+    use_esn = p.flags & (VppEnum.vl_api_ipsec_sad_flags_t.
+                         IPSEC_API_SAD_FLAG_USE_EXTENDED_SEQ_NUM)
     p.scapy_tra_sa = SecurityAssociation(
         encryption_type,
         spi=p.vpp_tra_spi,
@@ -107,7 +113,8 @@ def config_tra_params(p, encryption_type):
         crypt_key=p.crypt_key,
         auth_algo=p.auth_algo,
         auth_key=p.auth_key,
-        nat_t_header=p.nat_header)
+        nat_t_header=p.nat_header,
+        use_esn=use_esn)
     p.vpp_tra_sa = SecurityAssociation(
         encryption_type,
         spi=p.scapy_tra_spi,
@@ -115,7 +122,8 @@ def config_tra_params(p, encryption_type):
         crypt_key=p.crypt_key,
         auth_algo=p.auth_algo,
         auth_key=p.auth_key,
-        nat_t_header=p.nat_header)
+        nat_t_header=p.nat_header,
+        use_esn=use_esn)
 
 
 class TemplateIpsec(VppTestCase):
@@ -141,14 +149,16 @@ class TemplateIpsec(VppTestCase):
         """ empty method to be overloaded when necessary """
         pass
 
-    def setUp(self):
-        super(TemplateIpsec, self).setUp()
-
+    def setup_params(self):
         self.ipv4_params = IPsecIPv4Params()
         self.ipv6_params = IPsecIPv6Params()
         self.params = {self.ipv4_params.addr_type: self.ipv4_params,
                        self.ipv6_params.addr_type: self.ipv6_params}
 
+    def setUp(self):
+        super(TemplateIpsec, self).setUp()
+
+        self.setup_params()
         self.payload = "XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX"\
                        "XXXXXXXXXXXXXXXXXXXXX"
 
@@ -243,6 +253,7 @@ class IpsecTra4Tests(object):
     def test_tra_anti_replay(self, count=1):
         """ ipsec v4 transport anti-reply test """
         p = self.params[socket.AF_INET]
+        use_esn = p.vpp_tra_sa.use_esn
 
         # fire in a packet with seq number 1
         pkt = (Ether(src=self.tra_if.remote_mac,
@@ -262,6 +273,11 @@ class IpsecTra4Tests(object):
                                       seq_num=235))
         recv_pkts = self.send_and_expect(self.tra_if, [pkt], self.tra_if)
 
+        # replayed packets are dropped
+        self.send_and_assert_no_replies(self.tra_if, pkt * 3)
+        self.assert_packet_counter_equal(
+            '/err/%s/SA replayed packet' % self.tra4_decrypt_node_name, 3)
+
         # the window size is 64 packets
         # in window are still accepted
         pkt = (Ether(src=self.tra_if.remote_mac,
@@ -272,18 +288,6 @@ class IpsecTra4Tests(object):
                                       seq_num=172))
         recv_pkts = self.send_and_expect(self.tra_if, [pkt], self.tra_if)
 
-        # out of window are dropped
-        pkt = (Ether(src=self.tra_if.remote_mac,
-                     dst=self.tra_if.local_mac) /
-               p.scapy_tra_sa.encrypt(IP(src=self.tra_if.remote_ip4,
-                                         dst=self.tra_if.local_ip4) /
-                                      ICMP(),
-                                      seq_num=17))
-        self.send_and_assert_no_replies(self.tra_if, pkt * 17)
-
-        self.assert_packet_counter_equal(
-            '/err/%s/SA replayed packet' % self.tra4_decrypt_node_name, 17)
-
         # a packet that does not decrypt does not move the window forward
         bogus_sa = SecurityAssociation(self.encryption_type,
                                        p.vpp_tra_spi)
@@ -307,20 +311,71 @@ class IpsecTra4Tests(object):
                                       seq_num=234))
         self.send_and_expect(self.tra_if, [pkt], self.tra_if)
 
+        # out of window are dropped
+        pkt = (Ether(src=self.tra_if.remote_mac,
+                     dst=self.tra_if.local_mac) /
+               p.scapy_tra_sa.encrypt(IP(src=self.tra_if.remote_ip4,
+                                         dst=self.tra_if.local_ip4) /
+                                      ICMP(),
+                                      seq_num=17))
+        self.send_and_assert_no_replies(self.tra_if, pkt * 17)
+
+        if use_esn:
+            # an out of window error with ESN looks like a high sequence
+            # wrap. but since it isn't then the verify will fail.
+            self.assert_packet_counter_equal(
+                '/err/%s/Integrity check failed' %
+                self.tra4_decrypt_node_name, 34)
+
+        else:
+            self.assert_packet_counter_equal(
+                '/err/%s/SA replayed packet' %
+                self.tra4_decrypt_node_name, 20)
+
+        # valid packet moves the window over to 236
+        pkt = (Ether(src=self.tra_if.remote_mac,
+                     dst=self.tra_if.local_mac) /
+               p.scapy_tra_sa.encrypt(IP(src=self.tra_if.remote_ip4,
+                                         dst=self.tra_if.local_ip4) /
+                                      ICMP(),
+                                      seq_num=236))
+        rx = self.send_and_expect(self.tra_if, [pkt], self.tra_if)
+        decrypted = p.vpp_tra_sa.decrypt(rx[0][IP])
+
         # move VPP's SA to just before the seq-number wrap
         self.vapi.cli("test ipsec sa %d seq 0xffffffff" % p.scapy_tra_sa_id)
 
         # then fire in a packet that VPP should drop becuase it causes the
-        # seq number to wrap
+        # seq number to wrap, unless we're using exteneded.
         pkt = (Ether(src=self.tra_if.remote_mac,
                      dst=self.tra_if.local_mac) /
                p.scapy_tra_sa.encrypt(IP(src=self.tra_if.remote_ip4,
                                          dst=self.tra_if.local_ip4) /
                                       ICMP(),
-                                      seq_num=236))
-        self.send_and_assert_no_replies(self.tra_if, [pkt])
-        self.assert_packet_counter_equal(
-            '/err/%s/sequence number cycled' % self.tra4_encrypt_node_name, 1)
+                                      seq_num=237))
+
+        if use_esn:
+            rx = self.send_and_expect(self.tra_if, [pkt], self.tra_if)
+            # in order to decrpyt the high order number needs to wrap
+            p.vpp_tra_sa.seq_num = 0x100000000
+            decrypted = p.vpp_tra_sa.decrypt(rx[0][IP])
+
+            # send packets with high bits set
+            p.scapy_tra_sa.seq_num = 0x100000005
+            pkt = (Ether(src=self.tra_if.remote_mac,
+                         dst=self.tra_if.local_mac) /
+                   p.scapy_tra_sa.encrypt(IP(src=self.tra_if.remote_ip4,
+                                             dst=self.tra_if.local_ip4) /
+                                          ICMP(),
+                                          seq_num=0x100000005))
+            rx = self.send_and_expect(self.tra_if, [pkt], self.tra_if)
+            # in order to decrpyt the high order number needs to wrap
+            decrypted = p.vpp_tra_sa.decrypt(rx[0][IP])
+        else:
+            self.send_and_assert_no_replies(self.tra_if, [pkt])
+            self.assert_packet_counter_equal(
+                '/err/%s/sequence number cycled' %
+                self.tra4_encrypt_node_name, 1)
 
         # move the security-associations seq number on to the last we used
         self.vapi.cli("test ipsec sa %d seq 0x15f" % p.scapy_tra_sa_id)
diff --git a/test/test_ipsec_ah.py b/test/test_ipsec_ah.py
index 21080cad3d6..af65850253c 100644
--- a/test/test_ipsec_ah.py
+++ b/test/test_ipsec_ah.py
@@ -5,7 +5,7 @@ from scapy.layers.ipsec import AH
 
 from framework import VppTestRunner
 from template_ipsec import TemplateIpsec, IpsecTra46Tests, IpsecTun46Tests, \
-    config_tun_params, config_tra_params
+    config_tun_params, config_tra_params, IPsecIPv4Params, IPsecIPv6Params
 from template_ipsec import IpsecTcpTests
 from vpp_ipsec import VppIpsecSA, VppIpsecSpd, VppIpsecSpdEntry,\
         VppIpsecSpdItfBinding
@@ -85,6 +85,7 @@ class TemplateIpsecAh(TemplateIpsec):
         remote_tun_if_host = params.remote_tun_if_host
         addr_any = params.addr_any
         addr_bcast = params.addr_bcast
+        flags = params.flags
         e = VppEnum.vl_api_ipsec_spd_action_t
 
         params.tun_sa_in = VppIpsecSA(self, scapy_tun_sa_id, scapy_tun_spi,
@@ -92,14 +93,16 @@ class TemplateIpsecAh(TemplateIpsec):
                                       crypt_algo_vpp_id, crypt_key,
                                       self.vpp_ah_protocol,
                                       self.tun_if.local_addr[addr_type],
-                                      self.tun_if.remote_addr[addr_type])
+                                      self.tun_if.remote_addr[addr_type],
+                                      flags=flags)
         params.tun_sa_in.add_vpp_config()
         params.tun_sa_out = VppIpsecSA(self, vpp_tun_sa_id, vpp_tun_spi,
                                        auth_algo_vpp_id, auth_key,
                                        crypt_algo_vpp_id, crypt_key,
                                        self.vpp_ah_protocol,
                                        self.tun_if.remote_addr[addr_type],
-                                       self.tun_if.local_addr[addr_type])
+                                       self.tun_if.local_addr[addr_type],
+                                       flags=flags)
         params.tun_sa_out.add_vpp_config()
 
         params.spd_policy_in_any = VppIpsecSpdEntry(self, self.tun_spd,
@@ -160,8 +163,8 @@ class TemplateIpsecAh(TemplateIpsec):
         crypt_key = params.crypt_key
         addr_any = params.addr_any
         addr_bcast = params.addr_bcast
-        flags = (VppEnum.vl_api_ipsec_sad_flags_t.
-                 IPSEC_API_SAD_FLAG_USE_ANTI_REPLAY)
+        flags = params.flags | (VppEnum.vl_api_ipsec_sad_flags_t.
+                                IPSEC_API_SAD_FLAG_USE_ANTI_REPLAY)
         e = VppEnum.vl_api_ipsec_spd_action_t
 
         params.tra_sa_in = VppIpsecSA(self, scapy_tra_sa_id, scapy_tra_spi,
@@ -221,5 +224,26 @@ class TestIpsecAh2(TemplateIpsecAh, IpsecTcpTests):
     pass
 
 
+class TestIpsecAh3(TemplateIpsecAh, IpsecTra46Tests, IpsecTun46Tests):
+    """ Ipsec AH w/ ESN - TCP tests """
+
+    tra4_encrypt_node_name = "ah4-encrypt"
+    tra4_decrypt_node_name = "ah4-decrypt"
+    tra6_encrypt_node_name = "ah6-encrypt"
+    tra6_decrypt_node_name = "ah6-decrypt"
+    tun4_encrypt_node_name = "ah4-encrypt"
+    tun4_decrypt_node_name = "ah4-decrypt"
+    tun6_encrypt_node_name = "ah6-encrypt"
+    tun6_decrypt_node_name = "ah6-decrypt"
+
+    def setup_params(self):
+        self.ipv4_params = IPsecIPv4Params()
+        self.ipv6_params = IPsecIPv6Params()
+        self.params = {self.ipv4_params.addr_type: self.ipv4_params,
+                       self.ipv6_params.addr_type: self.ipv6_params}
+        for _, p in self.params.items():
+            p.flags = (VppEnum.vl_api_ipsec_sad_flags_t.
+                       IPSEC_API_SAD_FLAG_USE_EXTENDED_SEQ_NUM)
+
 if __name__ == '__main__':
     unittest.main(testRunner=VppTestRunner)