IPSec AH protocol enhancement in VPP native core

Change-Id: Iec5804d768485f4015bbf732d8d19ef2f24e6939
Signed-off-by: “mukeshyadav1984” <mukyadav@cisco.com>

1 files changed, 344 insertions, 0 deletions

diff --git a/src/vnet/ipsec/ah_encrypt.c b/src/vnet/ipsec/ah_encrypt.c
new file mode 100644
index 00000000000..6619d872013
--- /dev/null
+++ b/src/vnet/ipsec/ah_encrypt.c
@@ -0,0 +1,344 @@
+/*
+ * ah_encrypt.c : IPSec AH encrypt node
+ *
+ * Copyright (c) 2015 Cisco and/or its affiliates.
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at:
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <vnet/vnet.h>
+#include <vnet/api_errno.h>
+#include <vnet/ip/ip.h>
+
+#include <vnet/ipsec/ipsec.h>
+#include <vnet/ipsec/esp.h>
+#include <vnet/ipsec/ah.h>
+
+#define foreach_ah_encrypt_next                   \
+_(DROP, "error-drop")                              \
+_(IP4_LOOKUP, "ip4-lookup")                        \
+_(IP6_LOOKUP, "ip6-lookup")                        \
+_(INTERFACE_OUTPUT, "interface-output")
+
+#define _(v, s) AH_ENCRYPT_NEXT_##v,
+typedef enum
+{
+  foreach_ah_encrypt_next
+#undef _
+    AH_ENCRYPT_N_NEXT,
+} ah_encrypt_next_t;
+
+#define foreach_ah_encrypt_error                   \
+ _(RX_PKTS, "AH pkts received")                    \
+ _(SEQ_CYCLED, "sequence number cycled")
+
+
+typedef enum
+{
+#define _(sym,str) AH_ENCRYPT_ERROR_##sym,
+  foreach_ah_encrypt_error
+#undef _
+    AH_ENCRYPT_N_ERROR,
+} ah_encrypt_error_t;
+
+static char *ah_encrypt_error_strings[] = {
+#define _(sym,string) string,
+  foreach_ah_encrypt_error
+#undef _
+};
+
+vlib_node_registration_t ah_encrypt_node;
+
+typedef struct
+{
+  u32 spi;
+  u32 seq;
+  ipsec_integ_alg_t integ_alg;
+} ah_encrypt_trace_t;
+
+/* packet trace format function */
+static u8 *
+format_ah_encrypt_trace (u8 * s, va_list * args)
+{
+  CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
+  CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
+  ah_encrypt_trace_t *t = va_arg (*args, ah_encrypt_trace_t *);
+
+  s = format (s, "ah: spi %u seq %u integrity %U",
+	      t->spi, t->seq, format_ipsec_integ_alg, t->integ_alg);
+  return s;
+}
+
+static uword
+ah_encrypt_node_fn (vlib_main_t * vm,
+		    vlib_node_runtime_t * node, vlib_frame_t * from_frame)
+{
+  u32 n_left_from, *from, *to_next = 0, next_index;
+  int icv_size = 0;
+  from = vlib_frame_vector_args (from_frame);
+  n_left_from = from_frame->n_vectors;
+  ipsec_main_t *im = &ipsec_main;
+  ipsec_proto_main_t *em = &ipsec_proto_main;
+  next_index = node->cached_next_index;
+
+  while (n_left_from > 0)
+    {
+      u32 n_left_to_next;
+
+      vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
+
+      while (n_left_from > 0 && n_left_to_next > 0)
+	{
+	  u32 i_bi0, next0;
+	  vlib_buffer_t *i_b0 = 0;
+	  u32 sa_index0;
+	  ipsec_sa_t *sa0;
+	  ip4_and_ah_header_t *ih0, *oh0 = 0;
+	  ip6_and_ah_header_t *ih6_0, *oh6_0 = 0;
+	  u8 is_ipv6;
+	  u8 ip_hdr_size;
+	  u8 next_hdr_type;
+	  u8 transport_mode = 0;
+	  u8 tos = 0;
+	  u8 ttl = 0;
+
+	  i_bi0 = from[0];
+	  from += 1;
+	  n_left_from -= 1;
+	  n_left_to_next -= 1;
+	  next0 = AH_ENCRYPT_NEXT_DROP;
+
+	  i_b0 = vlib_get_buffer (vm, i_bi0);
+	  to_next[0] = i_bi0;
+	  to_next += 1;
+	  sa_index0 = vnet_buffer (i_b0)->ipsec.sad_index;
+	  sa0 = pool_elt_at_index (im->sad, sa_index0);
+
+	  if (PREDICT_FALSE (esp_seq_advance (sa0)))
+	    {
+	      clib_warning ("sequence number counter has cycled SPI %u",
+			    sa0->spi);
+	      vlib_node_increment_counter (vm, ah_encrypt_node.index,
+					   AH_ENCRYPT_ERROR_SEQ_CYCLED, 1);
+	      //TODO need to confirm if below is needed
+	      to_next[0] = i_bi0;
+	      to_next += 1;
+	      goto trace;
+	    }
+
+
+	  sa0->total_data_size += i_b0->current_length;
+
+	  ssize_t adv;
+	  ih0 = vlib_buffer_get_current (i_b0);
+	  ttl = ih0->ip4.ttl;
+	  tos = ih0->ip4.tos;
+
+	  is_ipv6 = (ih0->ip4.ip_version_and_header_length & 0xF0) == 0x60;
+	  /* is ipv6 */
+	  if (PREDICT_TRUE (sa0->is_tunnel))
+	    {
+	      if (PREDICT_TRUE (!is_ipv6))
+		adv = -sizeof (ip4_and_ah_header_t);
+	      else
+		adv = -sizeof (ip6_and_ah_header_t);
+	    }
+	  else
+	    {
+	      adv = -sizeof (ah_header_t);
+	    }
+
+	  icv_size =
+	    em->ipsec_proto_main_integ_algs[sa0->integ_alg].trunc_size;
+	  /*transport mode save the eth header before it is overwritten */
+	  if (PREDICT_FALSE (!sa0->is_tunnel))
+	    {
+	      ethernet_header_t *ieh0 = (ethernet_header_t *)
+		((u8 *) vlib_buffer_get_current (i_b0) -
+		 sizeof (ethernet_header_t));
+	      ethernet_header_t *oeh0 =
+		(ethernet_header_t *) ((u8 *) ieh0 + (adv - icv_size));
+	      clib_memcpy (oeh0, ieh0, sizeof (ethernet_header_t));
+	    }
+
+	  vlib_buffer_advance (i_b0, adv - icv_size);
+
+	  /* is ipv6 */
+	  if (PREDICT_FALSE (is_ipv6))
+	    {
+	      ih6_0 = (ip6_and_ah_header_t *) ih0;
+	      ip_hdr_size = sizeof (ip6_header_t);
+	      oh6_0 = vlib_buffer_get_current (i_b0);
+
+	      if (PREDICT_TRUE (sa0->is_tunnel))
+		{
+		  next_hdr_type = IP_PROTOCOL_IPV6;
+		  oh6_0->ip6.ip_version_traffic_class_and_flow_label =
+		    ih6_0->ip6.ip_version_traffic_class_and_flow_label;
+		}
+	      else
+		{
+		  next_hdr_type = ih6_0->ip6.protocol;
+		  memmove (oh6_0, ih6_0, sizeof (ip6_header_t));
+		}
+
+	      oh6_0->ip6.protocol = IP_PROTOCOL_IPSEC_AH;
+	      oh6_0->ip6.hop_limit = 254;
+	      oh6_0->ah.spi = clib_net_to_host_u32 (sa0->spi);
+	      oh6_0->ah.seq_no = clib_net_to_host_u32 (sa0->seq);
+	      oh6_0->ip6.payload_length =
+		clib_host_to_net_u16 (vlib_buffer_length_in_chain (vm, i_b0) -
+				      sizeof (ip6_header_t));
+	    }
+	  else
+	    {
+	      ip_hdr_size = sizeof (ip4_header_t);
+	      oh0 = vlib_buffer_get_current (i_b0);
+	      memset (oh0, 0, sizeof (ip4_and_ah_header_t));
+
+	      if (PREDICT_TRUE (sa0->is_tunnel))
+		{
+		  next_hdr_type = IP_PROTOCOL_IP_IN_IP;
+		}
+	      else
+		{
+		  next_hdr_type = ih0->ip4.protocol;
+		  memmove (oh0, ih0, sizeof (ip4_header_t));
+		}
+
+	      oh0->ip4.length =
+		clib_host_to_net_u16 (vlib_buffer_length_in_chain (vm, i_b0));
+	      oh0->ip4.ip_version_and_header_length = 0x45;
+	      oh0->ip4.fragment_id = 0;
+	      oh0->ip4.flags_and_fragment_offset = 0;
+	      oh0->ip4.ttl = 0;
+	      oh0->ip4.tos = 0;
+	      oh0->ip4.protocol = IP_PROTOCOL_IPSEC_AH;
+	      oh0->ah.spi = clib_net_to_host_u32 (sa0->spi);
+	      oh0->ah.seq_no = clib_net_to_host_u32 (sa0->seq);
+	      oh0->ip4.checksum = 0;
+	      oh0->ah.nexthdr = next_hdr_type;
+	      oh0->ah.hdrlen = 4;
+	    }
+
+
+
+	  if (PREDICT_TRUE
+	      (!is_ipv6 && sa0->is_tunnel && !sa0->is_tunnel_ip6))
+	    {
+	      oh0->ip4.src_address.as_u32 = sa0->tunnel_src_addr.ip4.as_u32;
+	      oh0->ip4.dst_address.as_u32 = sa0->tunnel_dst_addr.ip4.as_u32;
+
+	      next0 = AH_ENCRYPT_NEXT_IP4_LOOKUP;
+	      vnet_buffer (i_b0)->sw_if_index[VLIB_TX] = (u32) ~ 0;
+	    }
+	  else if (is_ipv6 && sa0->is_tunnel && sa0->is_tunnel_ip6)
+	    {
+	      oh6_0->ip6.src_address.as_u64[0] =
+		sa0->tunnel_src_addr.ip6.as_u64[0];
+	      oh6_0->ip6.src_address.as_u64[1] =
+		sa0->tunnel_src_addr.ip6.as_u64[1];
+	      oh6_0->ip6.dst_address.as_u64[0] =
+		sa0->tunnel_dst_addr.ip6.as_u64[0];
+	      oh6_0->ip6.dst_address.as_u64[1] =
+		sa0->tunnel_dst_addr.ip6.as_u64[1];
+
+	      next0 = AH_ENCRYPT_NEXT_IP6_LOOKUP;
+	      vnet_buffer (i_b0)->sw_if_index[VLIB_TX] = (u32) ~ 0;
+	    }
+	  else
+	    {
+	      transport_mode = 1;
+	      next0 = AH_ENCRYPT_NEXT_INTERFACE_OUTPUT;
+	    }
+
+	  u8 sig[64];
+	  memset (sig, 0, sizeof (sig));
+	  u8 *digest = NULL;
+	  {
+	    digest = vlib_buffer_get_current (i_b0) + ip_hdr_size + icv_size;
+	    memset (digest, 0, icv_size);
+	  }
+
+	  hmac_calc (sa0->integ_alg, sa0->integ_key,
+		     sa0->integ_key_len,
+		     (u8 *) vlib_buffer_get_current (i_b0),
+		     i_b0->current_length, sig, sa0->use_esn, sa0->seq_hi);
+
+	  memcpy (digest, (char *) &sig[0], 12);
+
+	  if (PREDICT_FALSE (is_ipv6))
+	    {
+	    }
+	  else
+	    {
+	      oh0->ip4.ttl = ttl;
+	      oh0->ip4.tos = tos;
+	      oh0->ip4.checksum = ip4_header_checksum (&oh0->ip4);
+	    }
+
+	  if (transport_mode)
+	    vlib_buffer_advance (i_b0, -sizeof (ethernet_header_t));;
+
+	trace:
+	  if (PREDICT_FALSE (i_b0->flags & VLIB_BUFFER_IS_TRACED))
+	    {
+	      i_b0->flags |= VLIB_BUFFER_IS_TRACED;
+	      ah_encrypt_trace_t *tr =
+		vlib_add_trace (vm, node, i_b0, sizeof (*tr));
+	      tr->spi = sa0->spi;
+	      tr->seq = sa0->seq - 1;
+	      tr->integ_alg = sa0->integ_alg;
+	    }
+
+	  vlib_validate_buffer_enqueue_x1 (vm, node, next_index,
+					   to_next, n_left_to_next, i_bi0,
+					   next0);
+	}
+      vlib_put_next_frame (vm, node, next_index, n_left_to_next);
+    }
+  vlib_node_increment_counter (vm, ah_encrypt_node.index,
+			       AH_ENCRYPT_ERROR_RX_PKTS,
+			       from_frame->n_vectors);
+
+  return from_frame->n_vectors;
+}
+
+
+/* *INDENT-OFF* */
+VLIB_REGISTER_NODE (ah_encrypt_node) = {
+  .function = ah_encrypt_node_fn,
+  .name = "ah-encrypt",
+  .vector_size = sizeof (u32),
+  .format_trace = format_ah_encrypt_trace,
+  .type = VLIB_NODE_TYPE_INTERNAL,
+
+  .n_errors = ARRAY_LEN(ah_encrypt_error_strings),
+  .error_strings = ah_encrypt_error_strings,
+
+  .n_next_nodes = AH_ENCRYPT_N_NEXT,
+  .next_nodes = {
+#define _(s,n) [AH_ENCRYPT_NEXT_##s] = n,
+    foreach_ah_encrypt_next
+#undef _
+  },
+};
+/* *INDENT-ON* */
+
+VLIB_NODE_FUNCTION_MULTIARCH (ah_encrypt_node, ah_encrypt_node_fn)
+/*
+ * fd.io coding-style-patch-verification: ON
+ *
+ * Local Variables:
+ * eval: (c-set-style "gnu")
+ * End:
+ */