Commit 01480e1c authored by Patrick McHardy's avatar Patrick McHardy Committed by David S. Miller
Browse files

[NETLINK]: Add nla_append() 



Used to append data to a message without a header or padding.

Signed-off-by: default avatarPatrick McHardy <kaber@trash.net>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 2eb9d75c

include/net/netlink.h

+3 −0
Original line number Diff line number Diff line
@@ -91,6 +91,7 @@ 
 *   nla_reserve_nohdr(skb, len)	reserve room for an attribute w/o hdr

 *   nla_put(skb, type, len, data)	add attribute to skb

 *   nla_put_nohdr(skb, len, data)	add attribute w/o hdr

 *   nla_append(skb, len, data)		append data to skb

 *

 * Attribute Construction for Basic Types:

 *   nla_put_u8(skb, type, value)	add u8 attribute to skb
@@ -254,6 +255,8 @@ extern int nla_put(struct sk_buff *skb, int attrtype, 
				int attrlen, const void *data);

extern int		nla_put_nohdr(struct sk_buff *skb, int attrlen,

				      const void *data);

extern int		nla_append(struct sk_buff *skb, int attrlen,

				   const void *data);



/**************************************************************************

 * Netlink Messages

net/netlink/attr.c

+19 −0
Original line number Diff line number Diff line
@@ -430,6 +430,24 @@ int nla_put_nohdr(struct sk_buff *skb, int attrlen, const void *data) 
	return 0;

}



/**

 * nla_append - Add a netlink attribute without header or padding

 * @skb: socket buffer to add attribute to

 * @attrlen: length of attribute payload

 * @data: head of attribute payload

 *

 * Returns -1 if the tailroom of the skb is insufficient to store

 * the attribute payload.

 */

int nla_append(struct sk_buff *skb, int attrlen, const void *data)

{

	if (unlikely(skb_tailroom(skb) < NLA_ALIGN(attrlen)))

		return -1;



	memcpy(skb_put(skb, attrlen), data, attrlen);

	return 0;

}



EXPORT_SYMBOL(nla_validate);

EXPORT_SYMBOL(nla_parse);

EXPORT_SYMBOL(nla_find);
@@ -445,3 +463,4 @@ EXPORT_SYMBOL(nla_put_nohdr); 
EXPORT_SYMBOL(nla_memcpy);

EXPORT_SYMBOL(nla_memcmp);

EXPORT_SYMBOL(nla_strcmp);

EXPORT_SYMBOL(nla_append);