From 01480e1cf5e2118eba8a8968239f3242072f9563 Mon Sep 17 00:00:00 2001 From: Patrick McHardy Date: Tue, 22 Jan 2008 22:10:59 -0800 Subject: [PATCH] [NETLINK]: Add nla_append() Used to append data to a message without a header or padding. Signed-off-by: Patrick McHardy Signed-off-by: David S. Miller --- include/net/netlink.h | 3 +++ net/netlink/attr.c | 19 +++++++++++++++++++ 2 files changed, 22 insertions(+) diff --git a/include/net/netlink.h b/include/net/netlink.h index a5e6d0e..a5506c4 100644 --- a/include/net/netlink.h +++ b/include/net/netlink.h @@ -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 diff --git a/net/netlink/attr.c b/net/netlink/attr.c index ec39d12..feb326f 100644 --- a/net/netlink/attr.c +++ b/net/netlink/attr.c @@ -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); -- 2.7.4