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author | Nicolas Dichtel <nicolas.dichtel@6wind.com> | 2016-04-21 18:58:24 +0200 |
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committer | David S. Miller <davem@davemloft.net> | 2016-04-21 14:22:12 -0400 |
commit | 089bf1a6a924b97a7e9f920bae6253a8ad581cf3 (patch) | |
tree | fe6f8593fe905c4304556d946379cdf7e28b5436 /lib | |
parent | 732912d727cd6deb3c1a05a8baa74b8ce8d510ac (diff) | |
download | linux-stable-089bf1a6a924b97a7e9f920bae6253a8ad581cf3.tar.gz linux-stable-089bf1a6a924b97a7e9f920bae6253a8ad581cf3.tar.bz2 linux-stable-089bf1a6a924b97a7e9f920bae6253a8ad581cf3.zip |
libnl: add more helpers to align attributes on 64-bit
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'lib')
-rw-r--r-- | lib/nlattr.c | 99 |
1 files changed, 99 insertions, 0 deletions
diff --git a/lib/nlattr.c b/lib/nlattr.c index f5907d23272d..2b82f1e2ebc2 100644 --- a/lib/nlattr.c +++ b/lib/nlattr.c @@ -355,6 +355,29 @@ struct nlattr *__nla_reserve(struct sk_buff *skb, int attrtype, int attrlen) EXPORT_SYMBOL(__nla_reserve); /** + * __nla_reserve_64bit - reserve room for attribute on the skb and align it + * @skb: socket buffer to reserve room on + * @attrtype: attribute type + * @attrlen: length of attribute payload + * + * Adds a netlink attribute header to a socket buffer and reserves + * room for the payload but does not copy it. It also ensure that this + * attribute will be 64-bit aign. + * + * The caller is responsible to ensure that the skb provides enough + * tailroom for the attribute header and payload. + */ +struct nlattr *__nla_reserve_64bit(struct sk_buff *skb, int attrtype, + int attrlen, int padattr) +{ + if (nla_need_padding_for_64bit(skb)) + nla_align_64bit(skb, padattr); + + return __nla_reserve(skb, attrtype, attrlen); +} +EXPORT_SYMBOL(__nla_reserve_64bit); + +/** * __nla_reserve_nohdr - reserve room for attribute without header * @skb: socket buffer to reserve room on * @attrlen: length of attribute payload @@ -397,6 +420,35 @@ struct nlattr *nla_reserve(struct sk_buff *skb, int attrtype, int attrlen) EXPORT_SYMBOL(nla_reserve); /** + * nla_reserve_64bit - reserve room for attribute on the skb and align it + * @skb: socket buffer to reserve room on + * @attrtype: attribute type + * @attrlen: length of attribute payload + * + * Adds a netlink attribute header to a socket buffer and reserves + * room for the payload but does not copy it. It also ensure that this + * attribute will be 64-bit aign. + * + * Returns NULL if the tailroom of the skb is insufficient to store + * the attribute header and payload. + */ +struct nlattr *nla_reserve_64bit(struct sk_buff *skb, int attrtype, int attrlen, + int padattr) +{ + size_t len; + + if (nla_need_padding_for_64bit(skb)) + len = nla_total_size_64bit(attrlen); + else + len = nla_total_size(attrlen); + if (unlikely(skb_tailroom(skb) < len)) + return NULL; + + return __nla_reserve_64bit(skb, attrtype, attrlen, padattr); +} +EXPORT_SYMBOL(nla_reserve_64bit); + +/** * nla_reserve_nohdr - reserve room for attribute without header * @skb: socket buffer to reserve room on * @attrlen: length of attribute payload @@ -436,6 +488,26 @@ void __nla_put(struct sk_buff *skb, int attrtype, int attrlen, EXPORT_SYMBOL(__nla_put); /** + * __nla_put_64bit - Add a netlink attribute to a socket buffer and align it + * @skb: socket buffer to add attribute to + * @attrtype: attribute type + * @attrlen: length of attribute payload + * @data: head of attribute payload + * + * The caller is responsible to ensure that the skb provides enough + * tailroom for the attribute header and payload. + */ +void __nla_put_64bit(struct sk_buff *skb, int attrtype, int attrlen, + const void *data, int padattr) +{ + struct nlattr *nla; + + nla = __nla_reserve_64bit(skb, attrtype, attrlen, padattr); + memcpy(nla_data(nla), data, attrlen); +} +EXPORT_SYMBOL(__nla_put_64bit); + +/** * __nla_put_nohdr - Add a netlink attribute without header * @skb: socket buffer to add attribute to * @attrlen: length of attribute payload @@ -474,6 +546,33 @@ int nla_put(struct sk_buff *skb, int attrtype, int attrlen, const void *data) EXPORT_SYMBOL(nla_put); /** + * nla_put_64bit - Add a netlink attribute to a socket buffer and align it + * @skb: socket buffer to add attribute to + * @attrtype: attribute type + * @attrlen: length of attribute payload + * @data: head of attribute payload + * + * Returns -EMSGSIZE if the tailroom of the skb is insufficient to store + * the attribute header and payload. + */ +int nla_put_64bit(struct sk_buff *skb, int attrtype, int attrlen, + const void *data, int padattr) +{ + size_t len; + + if (nla_need_padding_for_64bit(skb)) + len = nla_total_size_64bit(attrlen); + else + len = nla_total_size(attrlen); + if (unlikely(skb_tailroom(skb) < len)) + return -EMSGSIZE; + + __nla_put_64bit(skb, attrtype, attrlen, data, padattr); + return 0; +} +EXPORT_SYMBOL(nla_put_64bit); + +/** * nla_put_nohdr - Add a netlink attribute without header * @skb: socket buffer to add attribute to * @attrlen: length of attribute payload |