diff options
| -rw-r--r-- | include/uapi/linux/netfilter/nf_conntrack_common.h | 13 | ||||
| -rw-r--r-- | net/netfilter/nf_conntrack_netlink.c | 33 |
2 files changed, 33 insertions, 13 deletions
diff --git a/include/uapi/linux/netfilter/nf_conntrack_common.h b/include/uapi/linux/netfilter/nf_conntrack_common.h index 6a8e33dd4ecb..38fc383139f0 100644 --- a/include/uapi/linux/netfilter/nf_conntrack_common.h +++ b/include/uapi/linux/netfilter/nf_conntrack_common.h @@ -82,10 +82,6 @@ enum ip_conntrack_status { IPS_DYING_BIT = 9, IPS_DYING = (1 << IPS_DYING_BIT), - /* Bits that cannot be altered from userland. */ - IPS_UNCHANGEABLE_MASK = (IPS_NAT_DONE_MASK | IPS_NAT_MASK | - IPS_EXPECTED | IPS_CONFIRMED | IPS_DYING), - /* Connection has fixed timeout. */ IPS_FIXED_TIMEOUT_BIT = 10, IPS_FIXED_TIMEOUT = (1 << IPS_FIXED_TIMEOUT_BIT), @@ -101,6 +97,15 @@ enum ip_conntrack_status { /* Conntrack got a helper explicitly attached via CT target. */ IPS_HELPER_BIT = 13, IPS_HELPER = (1 << IPS_HELPER_BIT), + + /* Be careful here, modifying these bits can make things messy, + * so don't let users modify them directly. + */ + IPS_UNCHANGEABLE_MASK = (IPS_NAT_DONE_MASK | IPS_NAT_MASK | + IPS_EXPECTED | IPS_CONFIRMED | IPS_DYING | + IPS_SEQ_ADJUST | IPS_TEMPLATE), + + __IPS_MAX_BIT = 14, }; /* Connection tracking event types */ diff --git a/net/netfilter/nf_conntrack_netlink.c b/net/netfilter/nf_conntrack_netlink.c index e5f97777b1f4..86deed6a8db4 100644 --- a/net/netfilter/nf_conntrack_netlink.c +++ b/net/netfilter/nf_conntrack_netlink.c @@ -1419,6 +1419,24 @@ ctnetlink_parse_nat_setup(struct nf_conn *ct, } #endif +static void +__ctnetlink_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); + } +} + static int ctnetlink_change_status(struct nf_conn *ct, const struct nlattr * const cda[]) { @@ -1438,10 +1456,7 @@ ctnetlink_change_status(struct nf_conn *ct, const struct nlattr * const cda[]) /* ASSURED bit can only be set */ return -EBUSY; - /* Be careful here, modifying NAT bits can screw up things, - * so don't let users modify them directly if they don't pass - * nf_nat_range. */ - ct->status |= status & ~(IPS_NAT_DONE_MASK | IPS_NAT_MASK); + __ctnetlink_change_status(ct, status, 0); return 0; } @@ -1628,7 +1643,7 @@ ctnetlink_change_seq_adj(struct nf_conn *ct, if (ret < 0) return ret; - ct->status |= IPS_SEQ_ADJUST; + set_bit(IPS_SEQ_ADJUST_BIT, &ct->status); } if (cda[CTA_SEQ_ADJ_REPLY]) { @@ -1637,7 +1652,7 @@ ctnetlink_change_seq_adj(struct nf_conn *ct, if (ret < 0) return ret; - ct->status |= IPS_SEQ_ADJUST; + set_bit(IPS_SEQ_ADJUST_BIT, &ct->status); } return 0; @@ -2289,10 +2304,10 @@ ctnetlink_update_status(struct nf_conn *ct, const struct nlattr * const cda[]) /* This check is less strict than ctnetlink_change_status() * because callers often flip IPS_EXPECTED bits when sending * an NFQA_CT attribute to the kernel. So ignore the - * unchangeable bits but do not error out. + * unchangeable bits but do not error out. Also user programs + * are allowed to clear the bits that they are allowed to change. */ - ct->status = (status & ~IPS_UNCHANGEABLE_MASK) | - (ct->status & IPS_UNCHANGEABLE_MASK); + __ctnetlink_change_status(ct, status, ~status); return 0; } |