ipsec: move the IPSec SA pool out of ipsec_main

Type: refactor

this allows the ipsec_sa_get funtion to be moved from ipsec.h to
ipsec_sa.h where it belongs.
Also use ipsec_sa_get throughout the code base.

Signed-off-by: Neale Ranns <neale@graphiant.com>
Change-Id: I2dce726c4f7052b5507dd8dcfead0ed5604357df
diff --git a/src/vnet/ipsec/ipsec_sa.h b/src/vnet/ipsec/ipsec_sa.h
index a5756f5..705034e 100644
--- a/src/vnet/ipsec/ipsec_sa.h
+++ b/src/vnet/ipsec/ipsec_sa.h
@@ -223,6 +223,11 @@
 STATIC_ASSERT_OFFSET_OF (ipsec_sa_t, cacheline1, CLIB_CACHE_LINE_BYTES);
 STATIC_ASSERT_OFFSET_OF (ipsec_sa_t, cacheline2, 2 * CLIB_CACHE_LINE_BYTES);
 
+/**
+ * Pool of IPSec SAs
+ */
+extern ipsec_sa_t *ipsec_sa_pool;
+
 /*
  * Ensure that the IPsec data does not overlap with the IP data in
  * the buffer meta data
@@ -279,6 +284,7 @@
 typedef walk_rc_t (*ipsec_sa_walk_cb_t) (ipsec_sa_t * sa, void *ctx);
 extern void ipsec_sa_walk (ipsec_sa_walk_cb_t cd, void *ctx);
 
+extern u8 *format_ipsec_replay_window (u8 *s, va_list *args);
 extern u8 *format_ipsec_crypto_alg (u8 * s, va_list * args);
 extern u8 *format_ipsec_integ_alg (u8 * s, va_list * args);
 extern u8 *format_ipsec_sa (u8 * s, va_list * args);
@@ -508,6 +514,12 @@
 	  : (unix_time_now_nsec () % vlib_num_workers ()) + 1);
 }
 
+always_inline ipsec_sa_t *
+ipsec_sa_get (u32 sa_index)
+{
+  return (pool_elt_at_index (ipsec_sa_pool, sa_index));
+}
+
 #endif /* __IPSEC_SPD_SA_H__ */
 
 /*