linux/include/net/netfilter, branch v3.12

netfilter: synproxy: fix BUG_ON triggered by corrupt TCP packets

2013-09-30T10:44:38Z

TCP packets hitting the SYN proxy through the SYNPROXY target are not validated by TCP conntrack. When th->doff is below 5, an underflow happens when calculating the options length, causing skb_header_pointer() to return NULL and triggering the BUG_ON(). Handle this case gracefully by checking for NULL instead of using BUG_ON(). Reported-by: Martin Topholm Tested-by: Martin Topholm Signed-off-by: Patrick McHardy Signed-off-by: Pablo Neira Ayuso

netfilter: nf_conntrack: use RCU safe kfree for conntrack extensions

2013-09-13T09:58:40Z

Commit 68b80f11 (netfilter: nf_nat: fix RCU races) introduced RCU protection for freeing extension data when reallocation moves them to a new location. We need the same protection when freeing them in nf_ct_ext_free() in order to prevent a use-after-free by other threads referencing a NAT extension data via bysource list. Signed-off-by: Michal Kubecek Signed-off-by: Pablo Neira Ayuso

netfilter: add SYNPROXY core/target

2013-08-27T22:27:54Z

Add a SYNPROXY for netfilter. The code is split into two parts, the synproxy core with common functions and an address family specific target. The SYNPROXY receives the connection request from the client, responds with a SYN/ACK containing a SYN cookie and announcing a zero window and checks whether the final ACK from the client contains a valid cookie. It then establishes a connection to the original destination and, if successful, sends a window update to the client with the window size announced by the server. Support for timestamps, SACK, window scaling and MSS options can be statically configured as target parameters if the features of the server are known. If timestamps are used, the timestamp value sent back to the client in the SYN/ACK will be different from the real timestamp of the server. In order to now break PAWS, the timestamps are translated in the direction server->client. Signed-off-by: Patrick McHardy Tested-by: Martin Topholm Signed-off-by: Jesper Dangaard Brouer Signed-off-by: Pablo Neira Ayuso

netfilter: nf_conntrack: make sequence number adjustments usuable without NAT

2013-08-27T22:26:48Z

Split out sequence number adjustments from NAT and move them to the conntrack core to make them usable for SYN proxying. The sequence number adjustment information is moved to a seperate extend. The extend is added to new conntracks when a NAT mapping is set up for a connection using a helper. As a side effect, this saves 24 bytes per connection with NAT in the common case that a connection does not have a helper assigned. Signed-off-by: Patrick McHardy Tested-by: Martin Topholm Signed-off-by: Jesper Dangaard Brouer Signed-off-by: Pablo Neira Ayuso

netfilter: nfnetlink_queue: allow to attach expectations to conntracks

2013-08-13T14:32:10Z

This patch adds the capability to attach expectations via nfnetlink_queue. This is required by conntrack helpers that trigger expectations based on the first packet seen like the TFTP and the DHCPv6 user-space helpers. Signed-off-by: Pablo Neira Ayuso

netfilter: nf_conntrack: don't send destroy events from iterator

2013-08-09T10:03:33Z

Let nf_ct_delete handle delivery of the DESTROY event. Based on earlier patch from Pablo Neira. Signed-off-by: Florian Westphal Signed-off-by: Pablo Neira Ayuso

netfilter: nf_nat: change sequence number adjustments to 32 bits

2013-07-31T17:54:51Z

Using 16 bits is too small, when many adjustments happen the offsets might overflow and break the connection. Signed-off-by: Patrick McHardy Signed-off-by: Pablo Neira Ayuso

netfilter: nf_conntrack: remove duplicate code in ctnetlink

2013-07-31T16:51:23Z

ctnetlink contains copy-paste code from death_by_timeout. In order to avoid changing both places in upcoming event delivery patch, export death_by_timeout functionality and use it in the ctnetlink code. Based on earlier patch from Pablo Neira. Signed-off-by: Florian Westphal Signed-off-by: Pablo Neira Ayuso

netfilter: tproxy: remove nf_tproxy_core.h

2013-07-31T16:43:45Z

We've removed nf_tproxy_core.ko, so also remove its header. The lookup helpers are split and then moved to tproxy target/socket match. Signed-off-by: Florian Westphal Signed-off-by: Pablo Neira Ayuso

netfilter: tproxy: remove nf_tproxy_core, keep tw sk assigned to skb

2013-07-31T14:39:40Z

The module was "permanent", due to the special tproxy skb->destructor. Nowadays we have tcp early demux and its sock_edemux destructor in networking core which can be used instead. Thanks to early demux changes the input path now also handles "skb->sk is tw socket" correctly, so this no longer needs the special handling introduced with commit d503b30bd648b3cb4e5f50b65d27e389960cc6d9 (netfilter: tproxy: do not assign timewait sockets to skb->sk). Thus: - move assign_sock function to where its needed - don't prevent timewait sockets from being assigned to the skb - remove nf_tproxy_core. Signed-off-by: Florian Westphal Signed-off-by: Pablo Neira Ayuso