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| author | Lorenzo Bianconi <lorenzo@kernel.org> | 2022-07-21 15:42:41 +0200 |
|---|---|---|
| committer | Alexei Starovoitov <ast@kernel.org> | 2022-07-21 21:03:16 -0700 |
| commit | ef69aa3a986ef94f01ce8b5b619f550db54432fe (patch) | |
| tree | d9047f7ff0c1f05ad8765b2b06dbcbfa2826beda /net/netfilter/nf_conntrack_core.c | |
| parent | 0b3892364431684e883682b85d008979e08d4ce6 (diff) | |
| download | linux-ef69aa3a986ef94f01ce8b5b619f550db54432fe.tar.gz | |
net: netfilter: Add kfuncs to set and change CT status
Introduce bpf_ct_set_status and bpf_ct_change_status kfunc helpers in
order to set nf_conn field of allocated entry or update nf_conn status
field of existing inserted entry. Use nf_ct_change_status_common to
share the permitted status field changes between netlink and BPF side
by refactoring ctnetlink_change_status.
It is required to introduce two kfuncs taking nf_conn___init and nf_conn
instead of sharing one because KF_TRUSTED_ARGS flag causes strict type
checking. This would disallow passing nf_conn___init to kfunc taking
nf_conn, and vice versa. We cannot remove the KF_TRUSTED_ARGS flag as we
only want to accept refcounted pointers and not e.g. ct->master.
Hence, bpf_ct_set_* kfuncs are meant to be used on allocated CT, and
bpf_ct_change_* kfuncs are meant to be used on inserted or looked up
CT entry.
Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Co-developed-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Link: https://lore.kernel.org/r/20220721134245.2450-10-memxor@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Diffstat (limited to 'net/netfilter/nf_conntrack_core.c')
| -rw-r--r-- | net/netfilter/nf_conntrack_core.c | 40 |
1 files changed, 40 insertions, 0 deletions
diff --git a/net/netfilter/nf_conntrack_core.c b/net/netfilter/nf_conntrack_core.c index 572f59a5e93637..66a0aa8dbc3bf7 100644 --- a/net/netfilter/nf_conntrack_core.c +++ b/net/netfilter/nf_conntrack_core.c @@ -2807,4 +2807,44 @@ int __nf_ct_change_timeout(struct nf_conn *ct, u64 timeout) } EXPORT_SYMBOL_GPL(__nf_ct_change_timeout); +void __nf_ct_change_status(struct nf_conn *ct, unsigned long on, unsigned long off) +{ + unsigned int bit; + + /* Ignore these unchangable bits */ + on &= ~IPS_UNCHANGEABLE_MASK; + off &= ~IPS_UNCHANGEABLE_MASK; + + for (bit = 0; bit < __IPS_MAX_BIT; bit++) { + if (on & (1 << bit)) + set_bit(bit, &ct->status); + else if (off & (1 << bit)) + clear_bit(bit, &ct->status); + } +} +EXPORT_SYMBOL_GPL(__nf_ct_change_status); + +int nf_ct_change_status_common(struct nf_conn *ct, unsigned int status) +{ + unsigned long d; + + d = ct->status ^ status; + + if (d & (IPS_EXPECTED|IPS_CONFIRMED|IPS_DYING)) + /* unchangeable */ + return -EBUSY; + + if (d & IPS_SEEN_REPLY && !(status & IPS_SEEN_REPLY)) + /* SEEN_REPLY bit can only be set */ + return -EBUSY; + + if (d & IPS_ASSURED && !(status & IPS_ASSURED)) + /* ASSURED bit can only be set */ + return -EBUSY; + + __nf_ct_change_status(ct, status, 0); + return 0; +} +EXPORT_SYMBOL_GPL(nf_ct_change_status_common); + #endif |