[PATCH 2/5] ESP: Export esp_output_fill_trailer function

[Steffen Klassert <steffen.klassert@secunet.com>]

From: Raed Salem <raeds@mellanox.com>

The esp fill trailer method is identical for both
IPv6 and IPv4.

Share the implementation for esp6 and esp to avoid
code duplication in addition it could be also used
at various drivers code.

Signed-off-by: Raed Salem <raeds@mellanox.com>
Reviewed-by: Boris Pismenny <borisp@mellanox.com>
Reviewed-by: Saeed Mahameed <saeedm@mellanox.com>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
---
 include/net/esp.h | 16 ++++++++++++++++
 net/ipv4/esp4.c   | 16 ----------------
 net/ipv6/esp6.c   | 16 ----------------
 3 files changed, 16 insertions(+), 32 deletions(-)

diff --git a/include/net/esp.h b/include/net/esp.h
index 117652eb6ea3..9c5637d41d95 100644
--- a/include/net/esp.h
+++ b/include/net/esp.h
@@ -11,6 +11,22 @@ static inline struct ip_esp_hdr *ip_esp_hdr(const struct sk_buff *skb)
 	return (struct ip_esp_hdr *)skb_transport_header(skb);
 }
 
+static inline void esp_output_fill_trailer(u8 *tail, int tfclen, int plen, __u8 proto)
+{
+	/* Fill padding... */
+	if (tfclen) {
+		memset(tail, 0, tfclen);
+		tail += tfclen;
+	}
+	do {
+		int i;
+		for (i = 0; i < plen - 2; i++)
+			tail[i] = i + 1;
+	} while (0);
+	tail[plen - 2] = plen - 2;
+	tail[plen - 1] = proto;
+}
+
 struct esp_info {
 	struct	ip_esp_hdr *esph;
 	__be64	seqno;
diff --git a/net/ipv4/esp4.c b/net/ipv4/esp4.c
index 103c7d599a3c..8b07f3a4f2db 100644
--- a/net/ipv4/esp4.c
+++ b/net/ipv4/esp4.c
@@ -341,22 +341,6 @@ static void esp_output_done_esn(struct crypto_async_request *base, int err)
 	esp_output_done(base, err);
 }
 
-static void esp_output_fill_trailer(u8 *tail, int tfclen, int plen, __u8 proto)
-{
-	/* Fill padding... */
-	if (tfclen) {
-		memset(tail, 0, tfclen);
-		tail += tfclen;
-	}
-	do {
-		int i;
-		for (i = 0; i < plen - 2; i++)
-			tail[i] = i + 1;
-	} while (0);
-	tail[plen - 2] = plen - 2;
-	tail[plen - 1] = proto;
-}
-
 static struct ip_esp_hdr *esp_output_udp_encap(struct sk_buff *skb,
 					       int encap_type,
 					       struct esp_info *esp,
diff --git a/net/ipv6/esp6.c b/net/ipv6/esp6.c
index a3b403ba8f8f..11143d039f16 100644
--- a/net/ipv6/esp6.c
+++ b/net/ipv6/esp6.c
@@ -207,22 +207,6 @@ static void esp_output_done_esn(struct crypto_async_request *base, int err)
 	esp_output_done(base, err);
 }
 
-static void esp_output_fill_trailer(u8 *tail, int tfclen, int plen, __u8 proto)
-{
-	/* Fill padding... */
-	if (tfclen) {
-		memset(tail, 0, tfclen);
-		tail += tfclen;
-	}
-	do {
-		int i;
-		for (i = 0; i < plen - 2; i++)
-			tail[i] = i + 1;
-	} while (0);
-	tail[plen - 2] = plen - 2;
-	tail[plen - 1] = proto;
-}
-
 int esp6_output_head(struct xfrm_state *x, struct sk_buff *skb, struct esp_info *esp)
 {
 	u8 *tail;
-- 
2.17.1