- Add nft_pktinfo.pf to replace ops->pf
- Add nft_pktinfo.hook to replace ops->hooknum
This simplifies the code, makes it more readable, and likely reduces
cache line misses. Maintainability is enhanced as the details of
nft_hook_ops are of no concern to the recpients of nft_pktinfo.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Replace the array of registers passed to expressions by a struct nft_regs,
containing the verdict as a seperate member, which aliases to the
NFT_REG_VERDICT register.
This is needed to seperate the verdict from the data registers completely,
so their size can be changed.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
More recent GCC warns about two kinds of switch statement uses:
1) Switching on an enumeration, but not having an explicit case
statement for all members of the enumeration. To show the
compiler this is intentional, we simply add a default case
with nothing more than a break statement.
2) Switching on a boolean value. I think this warning is dumb
but nevertheless you get it wholesale with -Wswitch.
This patch cures all such warnings in netfilter.
Signed-off-by: David S. Miller <davem@davemloft.net>
Acked-by: Pablo Neira Ayuso <pablo@netfilter.org>
make C=1 CF=-D__CHECK_ENDIAN__ shows following:
net/bridge/netfilter/nft_reject_bridge.c:65:50: warning: incorrect type in argument 3 (different base types)
net/bridge/netfilter/nft_reject_bridge.c:65:50: expected restricted __be16 [usertype] protocol [..]
net/bridge/netfilter/nft_reject_bridge.c:102:37: warning: cast from restricted __be16
net/bridge/netfilter/nft_reject_bridge.c:102:37: warning: incorrect type in argument 1 (different base types) [..]
net/bridge/netfilter/nft_reject_bridge.c:121:50: warning: incorrect type in argument 3 (different base types) [..]
net/bridge/netfilter/nft_reject_bridge.c:168:52: warning: incorrect type in argument 3 (different base types) [..]
net/bridge/netfilter/nft_reject_bridge.c:233:52: warning: incorrect type in argument 3 (different base types) [..]
Caused by two (harmless) errors:
1. htons() instead of ntohs()
2. __be16 for protocol in nf_reject_ipXhdr_put API, use u8 instead.
Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
bridge reject handling is not straightforward, there are many subtle
differences depending on configuration.
skb->dev is either the bridge port (PRE_ROUTING) or the bridge
itself (INPUT), so we need to use indev instead.
Also, checksum validation will only work reliably if we trim skb
according to the l3 header size.
While at it, add csum validation for ipv6 and skip existing tests
if skb was already checked e.g. by GRO.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
The user can crash the kernel if it uses any of the existing NAT
expressions from the wrong hook, so add some code to validate this
when loading the rule.
This patch introduces nft_chain_validate_hooks() which is based on
an existing function in the bridge version of the reject expression.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This patch exports the functions nft_reject_iphdr_validate and
nft_reject_ip6hdr_validate to use it in follow up patches.
These functions check if the IPv4/IPv6 header is correct.
Signed-off-by: Alvaro Neira Ayuso <alvaroneay@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Fix:
net/bridge/netfilter/nft_reject_bridge.c:
In function 'nft_reject_br_send_v6_unreach':
net/bridge/netfilter/nft_reject_bridge.c:240:3:
error: implicit declaration of function 'csum_ipv6_magic'
csum_ipv6_magic(&nip6h->saddr, &nip6h->daddr,
^
make[3]: *** [net/bridge/netfilter/nft_reject_bridge.o] Error 1
Seen with powerpc:allmodconfig.
Fixes: 523b929d54 ("netfilter: nft_reject_bridge: don't use IP stack to reject traffic")
Cc: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Restrict the reject expression to the prerouting and input bridge
hooks. If we allow this to be used from forward or any other later
bridge hook, if the frame is flooded to several ports, we'll end up
sending several reject packets, one per cloned packet.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
If the packet is received via the bridge stack, this cannot reject
packets from the IP stack.
This adds functions to build the reject packet and send it from the
bridge stack. Comments and assumptions on this patch:
1) Validate the IPv4 and IPv6 headers before further processing,
given that the packet comes from the bridge stack, we cannot assume
they are clean. Truncated packets are dropped, we follow similar
approach in the existing iptables match/target extensions that need
to inspect layer 4 headers that is not available. This also includes
packets that are directed to multicast and broadcast ethernet
addresses.
2) br_deliver() is exported to inject the reject packet via
bridge localout -> postrouting. So the approach is similar to what
we already do in the iptables reject target. The reject packet is
sent to the bridge port from which we have received the original
packet.
3) The reject packet is forged based on the original packet. The TTL
is set based on sysctl_ip_default_ttl for IPv4 and per-net
ipv6.devconf_all hoplimit for IPv6.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This patch introduces the NFT_REJECT_ICMPX_UNREACH type which provides
an abstraction to the ICMP and ICMPv6 codes that you can use from the
inet and bridge tables, they are:
* NFT_REJECT_ICMPX_NO_ROUTE: no route to host - network unreachable
* NFT_REJECT_ICMPX_PORT_UNREACH: port unreachable
* NFT_REJECT_ICMPX_HOST_UNREACH: host unreachable
* NFT_REJECT_ICMPX_ADMIN_PROHIBITED: administratevely prohibited
You can still use the specific codes when restricting the rule to match
the corresponding layer 3 protocol.
I decided to not overload the existing NFT_REJECT_ICMP_UNREACH to have
different semantics depending on the table family and to allow the user
to specify ICMP family specific codes if they restrict it to the
corresponding family.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
So you can reject IPv4 and IPv6 packets from bridge tables. If the ether
proto is now known, default on dropping the packet instead.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
