crypto: add hmac truncate option

This reverts commit 785368e559dbdf50676f74f43f13423c817abb52.

Change-Id: I782ac2be4e161790c73ccd4b08492e2188a6d79d
Signed-off-by: Damjan Marion <damarion@cisco.com>
diff --git a/src/vnet/ipsec/esp.h b/src/vnet/ipsec/esp.h
index 74ab1f0..8e61d9d 100644
--- a/src/vnet/ipsec/esp.h
+++ b/src/vnet/ipsec/esp.h
@@ -219,6 +219,7 @@
   op->src = data;
   op->len = data_len;
   op->dst = signature;
+  op->hmac_trunc_len = sa->integ_trunc_size;
 #if 0
 
   HMAC_Init_ex (ctx, key, key_len, md, NULL);