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| author | Johannes Berg <johannes.berg@intel.com> | 2018-09-26 12:15:33 +0300 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2018-09-28 20:24:39 +0300 |
| commit | 9a659a35ba177cec30676e170fb6ed98157bcb0d (patch) | |
| tree | 0a551784a6b946553793306790e75e1bb69d4f83 /include/net/netlink.h | |
| parent | c29f1845b2b22974411278bad3a2ac0b7815dfb4 (diff) | |
| download | linux-9a659a35ba177cec30676e170fb6ed98157bcb0d.tar.xz | |
netlink: allow NLA_NESTED to specify nested policy to validate
Now that we have a validation_data pointer, and the len field in
the policy is unused for NLA_NESTED, we can allow using them both
to have nested validation. This can be nice in code, although we
still have to use nla_parse_nested() or similar which would also
take a policy; however, it also serves as documentation in the
policy without requiring a look at the code.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'include/net/netlink.h')
| -rw-r--r-- | include/net/netlink.h | 13 |
1 files changed, 11 insertions, 2 deletions
diff --git a/include/net/netlink.h b/include/net/netlink.h index 0d698215d4d9..91907852da1c 100644 --- a/include/net/netlink.h +++ b/include/net/netlink.h @@ -200,8 +200,10 @@ enum { * NLA_NUL_STRING Maximum length of string (excluding NUL) * NLA_FLAG Unused * NLA_BINARY Maximum length of attribute payload - * NLA_NESTED Don't use `len' field -- length verification is - * done by checking len of nested header (or empty) + * NLA_NESTED Length verification is done by checking len of + * nested header (or empty); len field is used if + * validation_data is also used, for the max attr + * number in the nested policy. * NLA_U8, NLA_U16, * NLA_U32, NLA_U64, * NLA_S8, NLA_S16, @@ -224,6 +226,10 @@ enum { * NLA_REJECT This attribute is always rejected and validation data * may point to a string to report as the error instead * of the generic one in extended ACK. + * NLA_NESTED Points to a nested policy to validate, must also set + * `len' to the max attribute number. + * Note that nla_parse() will validate, but of course not + * parse, the nested sub-policies. * All other Unused * * Example: @@ -247,6 +253,9 @@ struct nla_policy { #define NLA_POLICY_ETH_ADDR NLA_POLICY_EXACT_LEN(ETH_ALEN) #define NLA_POLICY_ETH_ADDR_COMPAT NLA_POLICY_EXACT_LEN_WARN(ETH_ALEN) +#define NLA_POLICY_NESTED(maxattr, policy) \ + { .type = NLA_NESTED, .validation_data = policy, .len = maxattr } + /** * struct nl_info - netlink source information * @nlh: Netlink message header of original request |