net: sctp: sctp_auth_make_key_vector: remove duplicate ntohs calls
Daniel Borkmann [Thu, 7 Feb 2013 01:41:39 +0000 (01:41 +0000)]
Instead of calling 3 times ntohs(random->param_hdr.length), 2 times
ntohs(hmacs->param_hdr.length), and 3 times ntohs(chunks->param_hdr.length)
within the same function, we only call each once and store it in a
variable.

Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Acked-by: Vlad Yasevich <vyasevich@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/sctp/auth.c

index 159b9bc..94a12de 100644 (file)
@@ -200,10 +200,14 @@ static struct sctp_auth_bytes *sctp_auth_make_key_vector(
        struct sctp_auth_bytes *new;
        __u32   len;
        __u32   offset = 0;
+       __u16   random_len, hmacs_len, chunks_len = 0;
 
-       len = ntohs(random->param_hdr.length) + ntohs(hmacs->param_hdr.length);
-        if (chunks)
-               len += ntohs(chunks->param_hdr.length);
+       random_len = ntohs(random->param_hdr.length);
+       hmacs_len = ntohs(hmacs->param_hdr.length);
+       if (chunks)
+               chunks_len = ntohs(chunks->param_hdr.length);
+
+       len = random_len + hmacs_len + chunks_len;
 
        new = kmalloc(sizeof(struct sctp_auth_bytes) + len, gfp);
        if (!new)
@@ -211,16 +215,15 @@ static struct sctp_auth_bytes *sctp_auth_make_key_vector(
 
        new->len = len;
 
-       memcpy(new->data, random, ntohs(random->param_hdr.length));
-       offset += ntohs(random->param_hdr.length);
+       memcpy(new->data, random, random_len);
+       offset += random_len;
 
        if (chunks) {
-               memcpy(new->data + offset, chunks,
-                       ntohs(chunks->param_hdr.length));
-               offset += ntohs(chunks->param_hdr.length);
+               memcpy(new->data + offset, chunks, chunks_len);
+               offset += chunks_len;
        }
 
-       memcpy(new->data + offset, hmacs, ntohs(hmacs->param_hdr.length));
+       memcpy(new->data + offset, hmacs, hmacs_len);
 
        return new;
 }