This adds the missing validation code to avoid the use of nat/masq from
non-nat chains. The validation assumes two possible configuration
scenarios:
1) Use of nat from base chain that is not of nat type. Reject this
configuration from the nft_*_init() path of the expression.
2) Use of nat from non-base chain. In this case, we have to wait until
the non-base chain is referenced by at least one base chain via
jump/goto. This is resolved from the nft_*_validate() path which is
called from nf_tables_check_loops().
The user gets an -EOPNOTSUPP in both cases.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
We have to register the notifiers in the masquerade expression from
the the module _init and _exit path.
This fixes crashes when removing the masquerade rule with no
ipt_MASQUERADE support in place (which was masking the problem).
Fixes: 9ba1f72 ("netfilter: nf_tables: add new nft_masq expression")
Signed-off-by: Arturo Borrero Gonzalez <arturo.borrero.glez@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
The nft_masq expression is intended to perform NAT in the masquerade flavour.
We decided to have the masquerade functionality in a separated expression other
than nft_nat.
Signed-off-by: Arturo Borrero Gonzalez <arturo.borrero.glez@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Pablo Neira Ayuso
Arturo Borrero