esp: Introduce a helper to setup the trailer

We need to setup the trailer in two different cases,
so add a helper to avoid code duplication.

Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>

diff --git a/net/ipv4/esp4.c b/net/ipv4/esp4.c
index 9e8d97133513c63ab2d81766ba24e77e9c8d5d86..b1e24446e2972444835dd85c02434f3b089ba552 100644 (file)
--- a/net/ipv4/esp4.c
+++ b/net/ipv4/esp4.c
@@ -182,6 +182,22 @@ 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 int esp_output(struct xfrm_state *x, struct sk_buff *skb)
 {
        struct esp_output_extra *extra;
@@ -304,18 +320,7 @@ static int esp_output(struct xfrm_state *x, struct sk_buff *skb)
 
                        tail = vaddr + pfrag->offset;
 
-                       /* 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;
+                       esp_output_fill_trailer(tail, tfclen, plen, proto);
 
                        kunmap_atomic(vaddr);
 
@@ -395,20 +400,9 @@ cow:
        esph = ip_esp_hdr(skb);
 
 skip_cow:
-       /* 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;
-       pskb_put(skb, trailer, clen - skb->len + alen);
+       esp_output_fill_trailer(tail, tfclen, plen, proto);
 
+       pskb_put(skb, trailer, clen - skb->len + alen);
        skb_push(skb, -skb_network_offset(skb));
        esph->seq_no = htonl(XFRM_SKB_CB(skb)->seq.output.low);
        esph->spi = x->id.spi;

diff --git a/net/ipv6/esp6.c b/net/ipv6/esp6.c
index a428ac6b7c74d1cf7038874897ca070ba82dbcfc..ff54faa756317047af5af661d070ba9a5eb65429 100644 (file)
--- a/net/ipv6/esp6.c
+++ b/net/ipv6/esp6.c
@@ -198,6 +198,22 @@ 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 int esp6_output(struct xfrm_state *x, struct sk_buff *skb)
 {
        int err;
@@ -284,18 +300,7 @@ static int esp6_output(struct xfrm_state *x, struct sk_buff *skb)
 
                        tail = vaddr + pfrag->offset;
 
-                       /* 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;
+                       esp_output_fill_trailer(tail, tfclen, plen, proto);
 
                        kunmap_atomic(vaddr);
 
@@ -375,20 +380,9 @@ cow:
        esph = ip_esp_hdr(skb);
 
 skip_cow:
-       /* 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;
-       pskb_put(skb, trailer, clen - skb->len + alen);
+       esp_output_fill_trailer(tail, tfclen, plen, proto);
 
+       pskb_put(skb, trailer, clen - skb->len + alen);
        skb_push(skb, -skb_network_offset(skb));
 
        esph->seq_no = htonl(XFRM_SKB_CB(skb)->seq.output.low);