diff options
| author | Thomas Graf <tgraf@suug.ch> | 2006-08-26 20:11:47 -0700 |
|---|---|---|
| committer | David S. Miller <davem@sunset.davemloft.net> | 2006-09-22 15:18:24 -0700 |
| commit | a5531a5d852008be40811496029012f4ad3093d1 (patch) | |
| tree | f59a1b240753ef4f0a672f256fc01d8a965793d1 /include/net | |
| parent | e3b4eadbea77ecb3c3a74d1bc81b392f454c7f2e (diff) | |
[NETLINK]: Improve string attribute validation
Introduces a new attribute type NLA_NUL_STRING to support NUL
terminated strings. Attributes of this kind require to carry
a terminating NUL within the maximum specified in the policy.
The `old' NLA_STRING which is not required to be NUL terminated
is extended to provide means to specify a maximum length of the
string.
Aims at easing the pain with using nla_strlcpy() on temporary
buffers.
Signed-off-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'include/net')
| -rw-r--r-- | include/net/netlink.h | 15 |
1 files changed, 11 insertions, 4 deletions
diff --git a/include/net/netlink.h b/include/net/netlink.h index bcb27e3a312..11dc2e7f679 100644 --- a/include/net/netlink.h +++ b/include/net/netlink.h @@ -167,6 +167,7 @@ enum { NLA_FLAG, NLA_MSECS, NLA_NESTED, + NLA_NUL_STRING, __NLA_TYPE_MAX, }; @@ -175,21 +176,27 @@ enum { /** * struct nla_policy - attribute validation policy * @type: Type of attribute or NLA_UNSPEC - * @minlen: Minimal length of payload required to be available + * @len: Type specific length of payload * * Policies are defined as arrays of this struct, the array must be * accessible by attribute type up to the highest identifier to be expected. * + * Meaning of `len' field: + * NLA_STRING Maximum length of string + * NLA_NUL_STRING Maximum length of string (excluding NUL) + * NLA_FLAG Unused + * All other Exact length of attribute payload + * * Example: * static struct nla_policy my_policy[ATTR_MAX+1] __read_mostly = { * [ATTR_FOO] = { .type = NLA_U16 }, - * [ATTR_BAR] = { .type = NLA_STRING }, - * [ATTR_BAZ] = { .minlen = sizeof(struct mystruct) }, + * [ATTR_BAR] = { .type = NLA_STRING, len = BARSIZ }, + * [ATTR_BAZ] = { .len = sizeof(struct mystruct) }, * }; */ struct nla_policy { u16 type; - u16 minlen; + u16 len; }; /** |