ipsec: anti-replay code cleanup

Change-Id: Ib73352d6be26d639a7f9d47ca0570a1248bff04a
Signed-off-by: Damjan Marion <damarion@cisco.com>

diff --git a/src/plugins/dpdk/ipsec/esp_decrypt.c b/src/plugins/dpdk/ipsec/esp_decrypt.c
index dcc276f..349f04c 100644 (file)
--- a/src/plugins/dpdk/ipsec/esp_decrypt.c
+++ b/src/plugins/dpdk/ipsec/esp_decrypt.c
@@ -140,7 +140,7 @@ dpdk_esp_decrypt_inline (vlib_main_t * vm,
       while (n_left_from > 0 && n_left_to_next > 0)
        {
          clib_error_t *error;
-         u32 bi0, sa_index0, seq, iv_size;
+         u32 bi0, sa_index0, iv_size;
          u8 trunc_size;
          vlib_buffer_t *b0;
          esp_header_t *esp0;
@@ -234,33 +234,21 @@ dpdk_esp_decrypt_inline (vlib_main_t * vm,
            }
 
          /* anti-replay check */
-         if (ipsec_sa_is_set_USE_ANTI_REPLAY (sa0))
+         if (ipsec_sa_anti_replay_check (sa0, &esp0->seq))
            {
-             int rv = 0;
-
-             seq = clib_net_to_host_u32 (esp0->seq);
-
-             if (PREDICT_TRUE (ipsec_sa_is_set_USE_EXTENDED_SEQ_NUM (sa0)))
-               rv = esp_replay_check_esn (sa0, seq);
+             clib_warning ("failed anti-replay check");
+             if (is_ip6)
+               vlib_node_increment_counter (vm,
+                                            dpdk_esp6_decrypt_node.index,
+                                            ESP_DECRYPT_ERROR_REPLAY, 1);
              else
-               rv = esp_replay_check (sa0, seq);
-
-             if (PREDICT_FALSE (rv))
-               {
-                 clib_warning ("failed anti-replay check");
-                 if (is_ip6)
-                   vlib_node_increment_counter (vm,
-                                                dpdk_esp6_decrypt_node.index,
-                                                ESP_DECRYPT_ERROR_REPLAY, 1);
-                 else
-                   vlib_node_increment_counter (vm,
-                                                dpdk_esp4_decrypt_node.index,
-                                                ESP_DECRYPT_ERROR_REPLAY, 1);
-                 to_next[0] = bi0;
-                 to_next += 1;
-                 n_left_to_next -= 1;
-                 goto trace;
-               }
+               vlib_node_increment_counter (vm,
+                                            dpdk_esp4_decrypt_node.index,
+                                            ESP_DECRYPT_ERROR_REPLAY, 1);
+             to_next[0] = bi0;
+             to_next += 1;
+             n_left_to_next -= 1;
+             goto trace;
            }
 
          if (is_ip6)
@@ -560,15 +548,7 @@ dpdk_esp_decrypt_post_inline (vlib_main_t * vm,
 
          iv_size = cipher_alg->iv_len;
 
-         if (ipsec_sa_is_set_USE_ANTI_REPLAY (sa0))
-           {
-             u32 seq;
-             seq = clib_host_to_net_u32 (esp0->seq);
-             if (PREDICT_TRUE (ipsec_sa_is_set_USE_EXTENDED_SEQ_NUM (sa0)))
-               esp_replay_advance_esn (sa0, seq);
-             else
-               esp_replay_advance (sa0, seq);
-           }
+         ipsec_sa_anti_replay_advance (sa0, &esp0->seq);
 
          /* if UDP encapsulation is used adjust the address of the IP header */
          if (ipsec_sa_is_set_UDP_ENCAP (sa0)

diff --git a/src/vnet/ipsec/ah_decrypt.c b/src/vnet/ipsec/ah_decrypt.c
index 87e1de1..cf95588 100644 (file)
--- a/src/vnet/ipsec/ah_decrypt.c
+++ b/src/vnet/ipsec/ah_decrypt.c
@@ -151,20 +151,10 @@ ah_decrypt_inline (vlib_main_t * vm,
          seq = clib_host_to_net_u32 (ah0->seq_no);
 
          /* anti-replay check */
-         if (ipsec_sa_is_set_USE_ANTI_REPLAY (sa0))
+         if (ipsec_sa_anti_replay_check (sa0, &ah0->seq_no))
            {
-             int rv = 0;
-
-             if (PREDICT_TRUE (ipsec_sa_is_set_USE_EXTENDED_SEQ_NUM (sa0)))
-               rv = esp_replay_check_esn (sa0, seq);
-             else
-               rv = esp_replay_check (sa0, seq);
-
-             if (PREDICT_FALSE (rv))
-               {
-                 i_b0->error = node->errors[AH_DECRYPT_ERROR_REPLAY];
-                 goto trace;
-               }
+             i_b0->error = node->errors[AH_DECRYPT_ERROR_REPLAY];
+             goto trace;
            }
 
          vlib_increment_combined_counter
@@ -210,15 +200,7 @@ ah_decrypt_inline (vlib_main_t * vm,
                  goto trace;
                }
 
-             if (PREDICT_TRUE (ipsec_sa_is_set_USE_ANTI_REPLAY (sa0)))
-               {
-                 if (PREDICT_TRUE
-                     (ipsec_sa_is_set_USE_EXTENDED_SEQ_NUM (sa0)))
-                   esp_replay_advance_esn (sa0, seq);
-                 else
-                   esp_replay_advance (sa0, seq);
-               }
-
+             ipsec_sa_anti_replay_advance (sa0, &ah0->seq_no);
            }
 
          vlib_buffer_advance (i_b0,

diff --git a/src/vnet/ipsec/esp.h b/src/vnet/ipsec/esp.h
index 1f894ab..cc12785 100644 (file)
--- a/src/vnet/ipsec/esp.h
+++ b/src/vnet/ipsec/esp.h
@@ -54,133 +54,13 @@ typedef CLIB_PACKED (struct {
 }) ip6_and_esp_header_t;
 /* *INDENT-ON* */
 
-#define ESP_WINDOW_SIZE                (64)
 #define ESP_SEQ_MAX            (4294967295UL)
 #define ESP_MAX_BLOCK_SIZE     (16)
 #define ESP_MAX_ICV_SIZE       (16)
 
 u8 *format_esp_header (u8 * s, va_list * args);
 
-always_inline int
-esp_replay_check (ipsec_sa_t * sa, u32 seq)
-{
-  u32 diff;
-
-  if (PREDICT_TRUE (seq > sa->last_seq))
-    return 0;
-
-  diff = sa->last_seq - seq;
-
-  if (ESP_WINDOW_SIZE > diff)
-    return (sa->replay_window & (1ULL << diff)) ? 1 : 0;
-  else
-    return 1;
-
-  return 0;
-}
-
-always_inline int
-esp_replay_check_esn (ipsec_sa_t * sa, u32 seq)
-{
-  u32 tl = sa->last_seq;
-  u32 th = sa->last_seq_hi;
-  u32 diff = tl - seq;
-
-  if (PREDICT_TRUE (tl >= (ESP_WINDOW_SIZE - 1)))
-    {
-      if (seq >= (tl - ESP_WINDOW_SIZE + 1))
-       {
-         sa->seq_hi = th;
-         if (seq <= tl)
-           return (sa->replay_window & (1ULL << diff)) ? 1 : 0;
-         else
-           return 0;
-       }
-      else
-       {
-         sa->seq_hi = th + 1;
-         return 0;
-       }
-    }
-  else
-    {
-      if (seq >= (tl - ESP_WINDOW_SIZE + 1))
-       {
-         sa->seq_hi = th - 1;
-         return (sa->replay_window & (1ULL << diff)) ? 1 : 0;
-       }
-      else
-       {
-         sa->seq_hi = th;
-         if (seq <= tl)
-           return (sa->replay_window & (1ULL << diff)) ? 1 : 0;
-         else
-           return 0;
-       }
-    }
-
-  return 0;
-}
-
 /* TODO seq increment should be atomic to be accessed by multiple workers */
-always_inline void
-esp_replay_advance (ipsec_sa_t * sa, u32 seq)
-{
-  u32 pos;
-
-  if (seq > sa->last_seq)
-    {
-      pos = seq - sa->last_seq;
-      if (pos < ESP_WINDOW_SIZE)
-       sa->replay_window = ((sa->replay_window) << pos) | 1;
-      else
-       sa->replay_window = 1;
-      sa->last_seq = seq;
-    }
-  else
-    {
-      pos = sa->last_seq - seq;
-      sa->replay_window |= (1ULL << pos);
-    }
-}
-
-always_inline void
-esp_replay_advance_esn (ipsec_sa_t * sa, u32 seq)
-{
-  int wrap = sa->seq_hi - sa->last_seq_hi;
-  u32 pos;
-
-  if (wrap == 0 && seq > sa->last_seq)
-    {
-      pos = seq - sa->last_seq;
-      if (pos < ESP_WINDOW_SIZE)
-       sa->replay_window = ((sa->replay_window) << pos) | 1;
-      else
-       sa->replay_window = 1;
-      sa->last_seq = seq;
-    }
-  else if (wrap > 0)
-    {
-      pos = ~seq + sa->last_seq + 1;
-      if (pos < ESP_WINDOW_SIZE)
-       sa->replay_window = ((sa->replay_window) << pos) | 1;
-      else
-       sa->replay_window = 1;
-      sa->last_seq = seq;
-      sa->last_seq_hi = sa->seq_hi;
-    }
-  else if (wrap < 0)
-    {
-      pos = ~seq + sa->last_seq + 1;
-      sa->replay_window |= (1ULL << pos);
-    }
-  else
-    {
-      pos = sa->last_seq - seq;
-      sa->replay_window |= (1ULL << pos);
-    }
-}
-
 always_inline int
 esp_seq_advance (ipsec_sa_t * sa)
 {

diff --git a/src/vnet/ipsec/esp_decrypt.c b/src/vnet/ipsec/esp_decrypt.c
index 7f3c320..9366619 100644 (file)
--- a/src/vnet/ipsec/esp_decrypt.c
+++ b/src/vnet/ipsec/esp_decrypt.c
@@ -134,7 +134,6 @@ esp_decrypt_inline (vlib_main_t * vm,
       esp_header_t *esp0;
       ipsec_sa_t *sa0;
       u32 sa_index0 = ~0;
-      u32 seq;
       ip4_header_t *ih4 = 0, *oh4 = 0;
       ip6_header_t *ih6 = 0, *oh6 = 0;
       u8 tunnel_mode = 1;
@@ -144,29 +143,18 @@ esp_decrypt_inline (vlib_main_t * vm,
       esp0 = vlib_buffer_get_current (ib[0]);
       sa_index0 = vnet_buffer (ib[0])->ipsec.sad_index;
       sa0 = pool_elt_at_index (im->sad, sa_index0);
-      seq = clib_host_to_net_u32 (esp0->seq);
 
       /* anti-replay check */
-      if (ipsec_sa_is_set_USE_ANTI_REPLAY (sa0))
+      if (ipsec_sa_anti_replay_check (sa0, &esp0->seq))
        {
-         int rv = 0;
-
-         if (PREDICT_TRUE (ipsec_sa_is_set_USE_EXTENDED_SEQ_NUM (sa0)))
-           rv = esp_replay_check_esn (sa0, seq);
-         else
-           rv = esp_replay_check (sa0, seq);
-
-         if (PREDICT_FALSE (rv))
-           {
-             u32 tmp, off = n_alloc - n_left_from;
-             /* send original packet to drop node */
-             tmp = from[off];
-             from[off] = new_bufs[off];
-             new_bufs[off] = tmp;
-             ib[0]->error = node->errors[ESP_DECRYPT_ERROR_REPLAY];
-             next[0] = ESP_DECRYPT_NEXT_DROP;
-             goto trace;
-           }
+         u32 tmp, off = n_alloc - n_left_from;
+         /* send original packet to drop node */
+         tmp = from[off];
+         from[off] = new_bufs[off];
+         new_bufs[off] = tmp;
+         ib[0]->error = node->errors[ESP_DECRYPT_ERROR_REPLAY];
+         next[0] = ESP_DECRYPT_NEXT_DROP;
+         goto trace;
        }
 
       vlib_increment_combined_counter
@@ -197,13 +185,7 @@ esp_decrypt_inline (vlib_main_t * vm,
            }
        }
 
-      if (PREDICT_TRUE (ipsec_sa_is_set_USE_ANTI_REPLAY (sa0)))
-       {
-         if (PREDICT_TRUE (ipsec_sa_is_set_USE_EXTENDED_SEQ_NUM (sa0)))
-           esp_replay_advance_esn (sa0, seq);
-         else
-           esp_replay_advance (sa0, seq);
-       }
+      ipsec_sa_anti_replay_advance (sa0, &esp0->seq);
 
       if ((sa0->crypto_alg >= IPSEC_CRYPTO_ALG_AES_CBC_128 &&
           sa0->crypto_alg <= IPSEC_CRYPTO_ALG_AES_CBC_256) ||

diff --git a/src/vnet/ipsec/ipsec_sa.h b/src/vnet/ipsec/ipsec_sa.h
index 1cd2153..44f9642 100644 (file)
--- a/src/vnet/ipsec/ipsec_sa.h
+++ b/src/vnet/ipsec/ipsec_sa.h
@@ -19,6 +19,8 @@
 #include <vnet/ip/ip.h>
 #include <vnet/fib/fib_node.h>
 
+#define IPSEC_SA_ANTI_REPLAY_WINDOW_SIZE (64)
+
 #define foreach_ipsec_crypto_alg    \
   _ (0, NONE, "none")               \
   _ (1, AES_CBC_128, "aes-cbc-128") \
@@ -94,7 +96,7 @@ typedef enum ipsec_sad_flags_t_
 #define _(v, f, s) IPSEC_SA_FLAG_##f = v,
   foreach_ipsec_sa_flags
 #undef _
-} __attribute__ ((packed)) ipsec_sa_flags_t;
+} __clib_packed ipsec_sa_flags_t;
 
 STATIC_ASSERT (sizeof (ipsec_sa_flags_t) == 1, "IPSEC SA flags > 1 byte");
 
@@ -216,6 +218,132 @@ extern uword unformat_ipsec_integ_alg (unformat_input_t * input,
                                       va_list * args);
 extern uword unformat_ipsec_key (unformat_input_t * input, va_list * args);
 
+always_inline int
+ipsec_sa_anti_replay_check (ipsec_sa_t * sa, u32 * seqp)
+{
+  u32 seq, diff, tl, th;
+  if ((sa->flags & IPSEC_SA_FLAG_USE_ANTI_REPLAY) == 0)
+    return 0;
+
+  seq = clib_net_to_host_u32 (*seqp);
+
+  if ((sa->flags & IPSEC_SA_FLAG_USE_EXTENDED_SEQ_NUM) == 0)
+    {
+
+      if (PREDICT_TRUE (seq > sa->last_seq))
+       return 0;
+
+      diff = sa->last_seq - seq;
+
+      if (IPSEC_SA_ANTI_REPLAY_WINDOW_SIZE > diff)
+       return (sa->replay_window & (1ULL << diff)) ? 1 : 0;
+      else
+       return 1;
+
+      return 0;
+    }
+
+  tl = sa->last_seq;
+  th = sa->last_seq_hi;
+  diff = tl - seq;
+
+  if (PREDICT_TRUE (tl >= (IPSEC_SA_ANTI_REPLAY_WINDOW_SIZE - 1)))
+    {
+      if (seq >= (tl - IPSEC_SA_ANTI_REPLAY_WINDOW_SIZE + 1))
+       {
+         sa->seq_hi = th;
+         if (seq <= tl)
+           return (sa->replay_window & (1ULL << diff)) ? 1 : 0;
+         else
+           return 0;
+       }
+      else
+       {
+         sa->seq_hi = th + 1;
+         return 0;
+       }
+    }
+  else
+    {
+      if (seq >= (tl - IPSEC_SA_ANTI_REPLAY_WINDOW_SIZE + 1))
+       {
+         sa->seq_hi = th - 1;
+         return (sa->replay_window & (1ULL << diff)) ? 1 : 0;
+       }
+      else
+       {
+         sa->seq_hi = th;
+         if (seq <= tl)
+           return (sa->replay_window & (1ULL << diff)) ? 1 : 0;
+         else
+           return 0;
+       }
+    }
+
+  return 0;
+}
+
+always_inline void
+ipsec_sa_anti_replay_advance (ipsec_sa_t * sa, u32 * seqp)
+{
+  u32 pos, seq;
+  if (PREDICT_TRUE (sa->flags & IPSEC_SA_FLAG_USE_ANTI_REPLAY) == 0)
+    return;
+
+  seq = clib_host_to_net_u32 (*seqp);
+  if (PREDICT_TRUE (sa->flags & IPSEC_SA_FLAG_USE_EXTENDED_SEQ_NUM))
+    {
+      int wrap = sa->seq_hi - sa->last_seq_hi;
+
+      if (wrap == 0 && seq > sa->last_seq)
+       {
+         pos = seq - sa->last_seq;
+         if (pos < IPSEC_SA_ANTI_REPLAY_WINDOW_SIZE)
+           sa->replay_window = ((sa->replay_window) << pos) | 1;
+         else
+           sa->replay_window = 1;
+         sa->last_seq = seq;
+       }
+      else if (wrap > 0)
+       {
+         pos = ~seq + sa->last_seq + 1;
+         if (pos < IPSEC_SA_ANTI_REPLAY_WINDOW_SIZE)
+           sa->replay_window = ((sa->replay_window) << pos) | 1;
+         else
+           sa->replay_window = 1;
+         sa->last_seq = seq;
+         sa->last_seq_hi = sa->seq_hi;
+       }
+      else if (wrap < 0)
+       {
+         pos = ~seq + sa->last_seq + 1;
+         sa->replay_window |= (1ULL << pos);
+       }
+      else
+       {
+         pos = sa->last_seq - seq;
+         sa->replay_window |= (1ULL << pos);
+       }
+    }
+  else
+    {
+      if (seq > sa->last_seq)
+       {
+         pos = seq - sa->last_seq;
+         if (pos < IPSEC_SA_ANTI_REPLAY_WINDOW_SIZE)
+           sa->replay_window = ((sa->replay_window) << pos) | 1;
+         else
+           sa->replay_window = 1;
+         sa->last_seq = seq;
+       }
+      else
+       {
+         pos = sa->last_seq - seq;
+         sa->replay_window |= (1ULL << pos);
+       }
+    }
+}
+
 #endif /* __IPSEC_SPD_SA_H__ */
 
 /*