Thomas Haller [Wed, 6 Sep 2023 11:52:05 +0000 (13:52 +0200)]
tests/shell: rework finding tests and add "--list-tests" option
Cleanup finding the test files. Also add a "--list-tests" option to see
which tests are found and would run.
Also get rid of the FIND="$(which find)" detection. Which system doesn't
have a working find? Also, we can just fail when we try to use find, and
don't need a check first.
This is still after "unshare", which will be addressed next.
Signed-off-by: Thomas Haller <thaller@redhat.com> Signed-off-by: Florian Westphal <fw@strlen.de>
Thomas Haller [Wed, 6 Sep 2023 11:52:04 +0000 (13:52 +0200)]
tests/shell: rework command line parsing in "run-tests.sh"
Parse the arguments in a loop, so that their order does not matter.
Also, soon more command line arguments will be added, and this way of
parsing seems more maintainable and flexible.
Currently this is still after the is-root check and after unshare. That
will be addressed later.
Signed-off-by: Thomas Haller <thaller@redhat.com> Signed-off-by: Florian Westphal <fw@strlen.de>
given:
table ip filter {
set test {
type ipv4_addr . ether_addr . mark
flags interval
elements = { 198.51.100.0/25 . 00:0b:0c:ca:cc:10-c1:a0:c1:cc:10:00 . 0x0000006f, }
}
}
We get lookup failure:
nft get element ip filter test { 198.51.100.1 . 00:0b:0c:ca:cc:10 . 0x6f }
Error: Could not process rule: No such file or directory
Its possible to work around this via dummy range somewhere in the key, e.g.
nft get element ip filter test { 198.51.100.1 . 00:0b:0c:ca:cc:10 . 0x6f-0x6f }
but that shouldn't be needed, so make sure the INTERVAL flag is enabled
for the queried element if the set is of interval type.
This field exposes internal kernel GRO/GSO packet aggregation
implementation details to userspace, provide a hint to the user to
understand better when matching on this field.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
evaluate: revisit anonymous set with single element optimization
This patch reworks it to perform this optimization from the evaluation
step of the relational expression. Hence, when optimizing for protocol
flags, use OP_EQ instead of OP_IMPLICIT, that is:
tcp flags { syn }
becomes (to represent an exact match):
tcp flags == syn
given OP_IMPLICIT and OP_EQ are not equivalent for flags.
01167c393a12 ("evaluate: do not remove anonymous set with protocol flags
and single element") disabled this optimization, which is enabled again
after this patch.
Fixes: 01167c393a12 ("evaluate: do not remove anonymous set with protocol flags and single element") Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Jorge Ortiz [Mon, 28 Aug 2023 19:09:10 +0000 (21:09 +0200)]
evaluate: place byteorder conversion after numgen for IP address datatypes
The numgen extension generates numbers in little-endian.
This can be very tricky when trying to combine it with IP addresses, which use big endian.
This change adds a new byteorder operation to convert data type endianness.
Before this patch:
$ sudo nft -d netlink add rule nat snat_chain snat to numgen inc mod 7 offset 0x0a000001
ip nat snat_chain
[ numgen reg 1 = inc mod 7 offset 167772161 ]
[ nat snat ip addr_min reg 1 ]
After this patch:
$ sudo nft -d netlink add rule nat snat_chain snat to numgen inc mod 7 offset 0x0a000001
ip nat snat_chain
[ numgen reg 1 = inc mod 7 offset 167772161 ]
[ byteorder reg 1 = hton(reg 1, 4, 4) ]
[ nat snat ip addr_min reg 1 ]
Regression tests have been modified to include these new cases.
Signed-off-by: Jorge Ortiz Escribano <jorge.ortiz.escribano@gmail.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Thomas Haller [Tue, 29 Aug 2023 18:54:10 +0000 (20:54 +0200)]
xt: avoid "-Wmissing-field-initializers" for "original_opts"
Avoid this warning with clang:
CC src/xt.lo
src/xt.c:353:9: error: missing field 'has_arg' initializer [-Werror,-Wmissing-field-initializers]
{ NULL },
^
The warning seems not very useful, because it's well understood that
specifying only some initializers leaves the remaining fields
initialized with the default. However, as this warning is only hit once
in the code base, it doesn't seem that we violate this style frequently.
Hence, fix it instead of disabling the warning.
Signed-off-by: Thomas Haller <thaller@redhat.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Thomas Haller [Tue, 29 Aug 2023 18:54:09 +0000 (20:54 +0200)]
src: silence "implicit-fallthrough" warnings
Gcc with "-Wextra" warns:
CC segtree.lo
segtree.c: In function 'get_set_interval_find':
segtree.c:129:28: error: this statement may fall through [-Werror=implicit-fallthrough=]
129 | if (expr_basetype(i->key)->type != TYPE_STRING)
| ^
segtree.c:134:17: note: here
134 | case EXPR_PREFIX:
| ^~~~
CC optimize.lo
optimize.c: In function 'rule_collect_stmts':
optimize.c:396:28: error: this statement may fall through [-Werror=implicit-fallthrough=]
396 | if (stmt->expr->left->etype == EXPR_CONCAT) {
| ^
optimize.c:400:17: note: here
400 | case STMT_VERDICT:
| ^~~~
Signed-off-by: Thomas Haller <thaller@redhat.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Thomas Haller [Tue, 29 Aug 2023 18:54:08 +0000 (20:54 +0200)]
utils: call abort() after BUG() macro
Otherwise, we get spurious warnings. The compiler should be aware that there is
no return from BUG(). Call abort() there, which is marked as __attribute__
((__noreturn__)).
In file included from ./include/nftables.h:6,
from ./include/rule.h:4,
from src/payload.c:26:
src/payload.c: In function 'icmp_dep_to_type':
./include/utils.h:39:34: error: this statement may fall through [-Werror=implicit-fallthrough=]
39 | #define BUG(fmt, arg...) ({ fprintf(stderr, "BUG: " fmt, ##arg); assert(0); })
| ~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
src/payload.c:791:17: note: in expansion of macro 'BUG'
791 | BUG("Invalid map for simple dependency");
| ^~~
src/payload.c:792:9: note: here
792 | case PROTO_ICMP_ECHO: return ICMP_ECHO;
| ^~~~
Signed-off-by: Thomas Haller <thaller@redhat.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Thomas Haller [Tue, 29 Aug 2023 12:53:37 +0000 (14:53 +0200)]
include: drop "format" attribute from nft_gmp_print()
nft_gmp_print() passes the format string and arguments to
gmp_vfprintf(). Note that the format string is then interpreted
by gmp, which also understand special specifiers like "%Zx".
Note that with clang we get various compiler warnings:
gcc doesn't warn, because to gcc 'Z' is a deprecated alias for 'z' and
because the 3rd argument of the attribute((format())) is zero (so gcc
doesn't validate the arguments). But Z specifier in gmp expects a
"mpz_t" value and not a size_t. It's really not the same thing.
The correct solution is not to mark the function to accept a printf format
string.
Fixes: 2535ba7006f2 ('src: get rid of printf') Signed-off-by: Thomas Haller <thaller@redhat.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Thomas Haller [Tue, 29 Aug 2023 12:53:36 +0000 (14:53 +0200)]
src: suppress "-Wunused-but-set-variable" warning with "parser_bison.c"
Clang warns:
parser_bison.c:7606:9: error: variable 'nft_nerrs' set but not used [-Werror,-Wunused-but-set-variable]
int yynerrs = 0;
^
parser_bison.c:72:25: note: expanded from macro 'yynerrs'
#define yynerrs nft_nerrs
^
Signed-off-by: Thomas Haller <thaller@redhat.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Thomas Haller [Tue, 29 Aug 2023 12:53:34 +0000 (14:53 +0200)]
src: rework SNPRINTF_BUFFER_SIZE() and handle truncation
Before, the macro asserts against truncation. This is despite the
callers still checked for truncation and tried to handle it. Probably
for good reason. With stmt_evaluate_log_prefix() it's not clear that the
code ensures that truncation cannot happen, so we must not assert
against it, but handle it.
Also,
- wrap the macro in "do { ... } while(0)" to make it more
function-like.
- evaluate macro arguments exactly once, to make it more function-like.
- take pointers to the arguments that are being modified.
- use assert() instead of abort().
- use size_t type for arguments related to the buffer size.
- drop "size". It was mostly redundant to "offset". We can know
everything we want based on "len" and "offset" alone.
- "offset" previously was incremented before checking for truncation.
So it would point somewhere past the buffer. This behavior does not
seem useful. Instead, on truncation "len" will be zero (as before) and
"offset" will point one past the buffer (one past the terminating
NUL).
Thereby, also fix a warning from clang:
evaluate.c:4134:9: error: variable 'size' set but not used [-Werror,-Wunused-but-set-variable]
size_t size = 0;
^
meta.c:1006:9: error: variable 'size' set but not used [-Werror,-Wunused-but-set-variable]
size_t size;
^
Signed-off-by: Thomas Haller <thaller@redhat.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Thomas Haller [Tue, 29 Aug 2023 12:53:33 +0000 (14:53 +0200)]
evaluate: fix check for truncation in stmt_evaluate_log_prefix()
Otherwise, nft crashes with prefix longer than 127 bytes:
# nft add rule x y log prefix \"eeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee\"
==159385==ERROR: AddressSanitizer: stack-buffer-overflow on address 0x7ffed5bf4a10 at pc 0x7f3134839269 bp 0x7ffed5bf48b0 sp 0x7ffed5bf4060
WRITE of size 129 at 0x7ffed5bf4a10 thread T0
#0 0x7f3134839268 in __interceptor_memset ../../../../src/libsanitizer/sanitizer_common/sanitizer_common_interceptors.inc:778
#1 0x7f3133e3074e in __mpz_export_data /tmp/nftables/src/gmputil.c:110
#2 0x7f3133d21d3c in expr_to_string /tmp/nftables/src/expression.c:192
#3 0x7f3133ded103 in netlink_gen_log_stmt /tmp/nftables/src/netlink_linearize.c:1148
#4 0x7f3133df33a1 in netlink_gen_stmt /tmp/nftables/src/netlink_linearize.c:1682
[...]
Fixes: e76bb3794018 ('src: allow for variables in the log prefix string') Signed-off-by: Thomas Haller <thaller@redhat.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Thomas Haller [Tue, 29 Aug 2023 12:53:32 +0000 (14:53 +0200)]
datatype: avoid cast-align warning with struct sockaddr result from getaddrinfo()
With CC=clang we get
datatype.c:625:11: error: cast from 'struct sockaddr *' to 'struct sockaddr_in *' increases required alignment from 2 to 4 [-Werror,-Wcast-align]
addr = ((struct sockaddr_in *)ai->ai_addr)->sin_addr;
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
datatype.c:690:11: error: cast from 'struct sockaddr *' to 'struct sockaddr_in6 *' increases required alignment from 2 to 4 [-Werror,-Wcast-align]
addr = ((struct sockaddr_in6 *)ai->ai_addr)->sin6_addr;
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
datatype.c:826:11: error: cast from 'struct sockaddr *' to 'struct sockaddr_in *' increases required alignment from 2 to 4 [-Werror,-Wcast-align]
port = ((struct sockaddr_in *)ai->ai_addr)->sin_port;
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Fix that by casting to (void*) first. Also, add an assertion that the
type is as expected.
For inet_service_type_parse(), differentiate between AF_INET and
AF_INET6. It might not have been a problem in practice, because the
struct offsets of sin_port/sin6_port are identical.
Signed-off-by: Thomas Haller <thaller@redhat.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Thomas Haller [Tue, 29 Aug 2023 12:53:31 +0000 (14:53 +0200)]
netlink: avoid "-Wenum-conversion" warning in parser_bison.y
Clang warns:
parser_bison.y:3658:83: error: implicit conversion from enumeration type 'enum nft_nat_types' to different enumeration type 'enum nft_nat_etypes' [-Werror,-Wenum-conversion]
{ (yyval.stmt) = nat_stmt_alloc(&(yyloc), NFT_NAT_SNAT); }
~~~~~~~~~~~~~~ ^~~~~~~~~~~~
parser_bison.y:3659:83: error: implicit conversion from enumeration type 'enum nft_nat_types' to different enumeration type 'enum nft_nat_etypes' [-Werror,-Wenum-conversion]
{ (yyval.stmt) = nat_stmt_alloc(&(yyloc), NFT_NAT_DNAT); }
~~~~~~~~~~~~~~ ^~~~~~~~~~~~
Signed-off-by: Thomas Haller <thaller@redhat.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Thomas Haller [Tue, 29 Aug 2023 12:53:30 +0000 (14:53 +0200)]
netlink: avoid "-Wenum-conversion" warning in dtype_map_from_kernel()
Clang warns:
netlink.c:806:26: error: implicit conversion from enumeration type 'enum nft_data_types' to different enumeration type 'enum datatypes' [-Werror,-Wenum-conversion]
return datatype_lookup(type);
~~~~~~~~~~~~~~~ ^~~~
Signed-off-by: Thomas Haller <thaller@redhat.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Phil Sutter [Tue, 29 Aug 2023 13:22:56 +0000 (15:22 +0200)]
tests: monitor: Fix time format in ct timeout test
The old "plain" numbers are still accepted (and assumed to be in
seconds), but output will use units which is unexpected due to 'O -'.
Adjust input instead of adding this subtly different output line.
Fixes: 5c25c5a35cbd2 ("parser: allow ct timeouts to use time_spec values") Signed-off-by: Phil Sutter <phil@nwl.cc>
Phil Sutter [Fri, 25 Aug 2023 11:49:31 +0000 (13:49 +0200)]
evaluate: Drop dead code from expr_evaluate_mapping()
Since commit 343a51702656a ("src: store expr, not dtype to track data in
sets"), set->data is allocated for object maps in set_evaluate(), all
other map types have set->data initialized by the parser already,
set_evaluate() also checks that.
Drop the confusing check, later in the function set->data is
dereferenced unconditionally.
Fixes: 343a51702656a ("src: store expr, not dtype to track data in sets") Signed-off-by: Phil Sutter <phil@nwl.cc>
Thomas Haller [Fri, 25 Aug 2023 11:36:33 +0000 (13:36 +0200)]
include: include <std{bool,int}.h> via <nft.h>
There is a minimum base that all our sources will end up needing. This
is what <nft.h> provides.
Add <stdbool.h> and <stdint.h> there. It's unlikely that we want to
implement anything, without having "bool" and "uint32_t" types
available.
Yes, this means the internal headers are not self-contained, with
respect to what <nft.h> provides. This is the exception to the rule, and
our internal headers should rely to have <nft.h> included for them.
They should not include <nft.h> themselves, because <nft.h> needs always
be included as first. So when an internal header would include <nft.h>
it would be unnecessary, because the header is *always* included
already.
Signed-off-by: Thomas Haller <thaller@redhat.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Thomas Haller [Fri, 25 Aug 2023 11:36:32 +0000 (13:36 +0200)]
configure: use AC_USE_SYSTEM_EXTENSIONS to get _GNU_SOURCE
Let "configure" detect which features are available. Also, nftables is a
Linux project, so portability beyond gcc/clang and glibc/musl is less
relevant. And even if it were, then feature detection by "configure"
would still be preferable.
Thomas Haller [Fri, 25 Aug 2023 11:36:31 +0000 (13:36 +0200)]
include: don't define _GNU_SOURCE in public header
_GNU_SOURCE is supposed to be defined as first thing, before including any
libc headers. Defining it in the public header of nftables is wrong, because
it would only (somewhat) work if the user includes the nftables header as first
thing too. But that is not what users commonly would do, in particular with
autotools projects, where users would include <config.h> first.
It's also unnecessary. Nothing in "nftables/libnftables.h" itself
requires _GNU_SOURCE. Drop it.
Signed-off-by: Thomas Haller <thaller@redhat.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Thomas Haller [Fri, 25 Aug 2023 11:36:30 +0000 (13:36 +0200)]
src: add <nft.h> header and include it as first
<config.h> is generated by the configure script. As it contains our
feature detection, it want to use it everywhere.
Likewise, in some of our sources, we define _GNU_SOURCE. This defines
the C variant we want to use. Such a define need to come before anything
else, and it would be confusing if different source files adhere to a
different C variant. It would be good to use autoconf's
AC_USE_SYSTEM_EXTENSIONS, in which case we would also need to ensure
that <config.h> is always included as first.
Instead of going through all source files and include <config.h> as
first, add a new header "include/nft.h", which is supposed to be
included in all our sources (and as first).
This will also allow us later to prepare some common base, like include
<stdbool.h> everywhere.
We aim that headers are self-contained, so that they can be included in
any order. Which, by the way, already didn't work because some headers
define _GNU_SOURCE, which would only work if the header gets included as
first. <nft.h> is however an exception to the rule: everything we compile
shall rely on having <nft.h> header included as first. This applies to
source files (which explicitly include <nft.h>) and to internal header
files (which are only compiled indirectly, by being included from a source
file).
Note that <config.h> has no include guards, which is at least ugly to
include multiple times. It doesn't cause problems in practice, because
it only contains defines and the compiler doesn't warn about redefining
a macro with the same value. Still, <nft.h> also ensures to include
<config.h> exactly once.
Signed-off-by: Thomas Haller <thaller@redhat.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Thomas Haller [Fri, 25 Aug 2023 11:36:29 +0000 (13:36 +0200)]
meta: define _GNU_SOURCE to get strptime() from <time.h>
To use `strptime()`, the documentation indicates
#define _XOPEN_SOURCE
#include <time.h>
However, previously this was done wrongly.
For example, when building with musl we got a warning:
CC meta.lo
meta.c:40: warning: "_XOPEN_SOURCE" redefined
40 | #define _XOPEN_SOURCE
|
In file included from /usr/include/errno.h:8,
from meta.c:13:
/usr/include/features.h:16: note: this is the location of the previous definition
16 | #define _XOPEN_SOURCE 700
|
Defining "__USE_XOPEN" is wrong. This is a glibc internal define not for
the user.
Note that if we just set _XOPEN_SOURCE (or _XOPEN_SOURCE=700), we won't
get other things like "struct tm.tm_gmtoff".
Instead, we already define _GNU_SOURCE at other places. Do that here
too, it will give us strptime() and all is good.
Also, those directives should be defined as first thing (or via "-D"
command line). See [1].
This is also important, because to use "time_t" in a header, we would
need to include <time.h>. That only works, if we get the feature test
macros right. That is, define the _?_SOURCE macro as first thing.
Thomas Haller [Fri, 18 Aug 2023 09:40:41 +0000 (11:40 +0200)]
py: add Nftables.{get,set}_input_flags() API
Similar to the existing Nftables.{get,set}_debug() API.
Only notable (internal) difference is that nft_ctx_input_set_flags()
returns the old value already, so we don't need to call
Nftables.get_input_flags() first.
The benefit of this API, is that it follows the existing API for debug
flags. Also, when future flags are added it requires few changes to the
python code.
Signed-off-by: Thomas Haller <thaller@redhat.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Thomas Haller [Fri, 18 Aug 2023 09:40:40 +0000 (11:40 +0200)]
py: extract flags helper functions for set_debug()/get_debug()
Will be re-used for nft_ctx_input_set_flags() and
nft_ctx_input_get_flags().
There are changes in behavior here.
- when passing an unrecognized string (e.g. `ctx.set_debug('foo')` or
`ctx.set_debug(['foo'])`), a ValueError is now raised instead of a
KeyError.
- when passing an out-of-range integer, now a ValueError is no raised.
Previously the integer was truncated to 32bit.
Changing the exception is an API change, but most likely nobody will
care or try to catch a KeyError to find out whether a flag is supported.
Especially, since such a check would be better performed via `'foo' in
ctx.debug_flags`.
In other cases, a TypeError is raised as before.
Signed-off-by: Thomas Haller <thaller@redhat.com> Reviewed-by: Phil Sutter <phil@nwl.cc> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Thomas Haller [Fri, 18 Aug 2023 09:40:39 +0000 (11:40 +0200)]
py: fix exception during cleanup of half-initialized Nftables
When we create a Nftables instance against an older library version,
we might not find a symbol and fail with an exception when initializing
the context object.
Then, __del__() is still called, but resulting in a second exception
because self.__ctx is not set. Avoid that second exception.
$ python -c 'import nftables; nftables.Nftables()'
Traceback (most recent call last):
File "<string>", line 1, in <module>
File "/data/src/nftables/py/nftables.py", line 90, in __init__
self.nft_ctx_input_get_flags = lib.nft_ctx_input_get_flags
^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/usr/lib64/python3.11/ctypes/__init__.py", line 389, in __getattr__
func = self.__getitem__(name)
^^^^^^^^^^^^^^^^^^^^^^
File "/usr/lib64/python3.11/ctypes/__init__.py", line 394, in __getitem__
func = self._FuncPtr((name_or_ordinal, self))
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
AttributeError: /lib64/libnftables.so.1: undefined symbol: nft_ctx_input_get_flags
Exception ignored in: <function Nftables.__del__ at 0x7f6315a2c540>
Traceback (most recent call last):
File "/data/src/nftables/py/nftables.py", line 166, in __del__
self.nft_ctx_free(self.__ctx)
^^^^^^^^^^^^^^^^^
AttributeError: 'Nftables' object has no attribute 'nft_ctx_free'
Signed-off-by: Thomas Haller <thaller@redhat.com> Reviewed-by: Phil Sutter <phil@nwl.cc> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Thomas Haller [Fri, 18 Aug 2023 09:40:38 +0000 (11:40 +0200)]
src: add input flag NFT_CTX_INPUT_JSON to enable JSON parsing
By default, the input is parsed using the nftables grammar. When setting
NFT_CTX_OUTPUT_JSON flag, nftables will first try to parse the input as
JSON before falling back to the nftables grammar.
But NFT_CTX_OUTPUT_JSON flag also turns on JSON for the output. Add a
flag NFT_CTX_INPUT_JSON which allows to treat only the input as JSON,
but keep the output mode unchanged.
Signed-off-by: Thomas Haller <thaller@redhat.com> Reviewed-by: Phil Sutter <phil@nwl.cc> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Thomas Haller [Fri, 18 Aug 2023 09:40:37 +0000 (11:40 +0200)]
src: add input flag NFT_CTX_INPUT_NO_DNS to avoid blocking
getaddrinfo() blocks while trying to resolve the name. Blocking the
caller of the library is in many cases undesirable. Also, while
reconfiguring the firewall, it's not clear that resolving names via
the network will work or makes sense.
Add a new input flag NFT_CTX_INPUT_NO_DNS to opt-out from getaddrinfo()
and only accept plain IP addresses.
We could also use AI_NUMERICHOST with getaddrinfo() instead of
inet_pton(). By parsing via inet_pton(), we are better aware of
what we expect and can generate a better error message in case of
failure.
Signed-off-by: Thomas Haller <thaller@redhat.com> Reviewed-by: Phil Sutter <phil@nwl.cc> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
evaluate: error out on meter overlap with an existing set/map declaration
One of the problems with meters is that they use the set/map
infrastructure behind the scenes which might be confusing to users.
This patch errors out in case user declares a meter whose name overlaps
with an existing set/map:
meter.nft:15:18-91: Error: File exists; meter ‘syn4-meter’ overlaps an existing set ‘syn4-meter’ in family inet
tcp dport 22 meter syn4-meter { ip saddr . tcp dport timeout 5m limit rate 20/minute } counter accept
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
An old 5.10 kernel bails out simply with EEXIST, with this patch a
better hint is provided.
Dynamic sets are preferred over meters these days.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
cache: chain listing implicitly sets on terse option
If user specifies a chain to be listed (which is internally handled via
filtering options), then toggle NFT_CACHE_TERSE to skip fetching set
content from kernel for non-anonymous sets.
With a large IPv6 set with bogons, before this patch:
# time nft list chain inet raw x
table inet raw {
chain x {
ip6 saddr @bogons6
ip6 saddr { aaaa::, bbbb:: }
}
}
real 0m2,913s
user 0m1,345s
sys 0m1,568s
After this patch:
# time nft list chain inet raw prerouting
table inet raw {
chain x {
ip6 saddr @bogons6
ip6 saddr { aaaa::, bbbb:: }
}
}
real 0m0,056s
user 0m0,018s
sys 0m0,039s
This speeds up chain listing in the presence of a large set.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Phil Sutter [Wed, 23 Aug 2023 16:18:49 +0000 (18:18 +0200)]
tests: shell: Stabilize sets/0043concatenated_ranges_0 test
On a slow system, one of the 'delete element' commands would
occasionally fail. Assuming it can only happen if the 2s timeout passes
"too quickly", work around it by adding elements with a 2m timeout
instead and when wanting to test the element expiry just drop and add
the element again with a short timeout.
Fixes: 6231d3fa4af1e ("tests: shell: Fix for unstable sets/0043concatenated_ranges_0") Signed-off-by: Phil Sutter <phil@nwl.cc>
Phil Sutter [Wed, 23 Aug 2023 09:18:53 +0000 (11:18 +0200)]
tests: shell: Stabilize sets/reset_command_0 test
Timeout/expiry value testing based on seconds is way too fragile,
especially with slow debug kernels. Rewrite the unit to test
minute-based values. This means it is no longer feasible to wait for
values to sufficiently change, so instead specify an 'expires' value
when creating the ruleset and drop the 'sleep' call.
While being at it:
- Combine 'get element' and 'reset element' calls into one, assert the
relevant (sanitized) line appears twice in output instead of comparing
with 'diff'.
- Turn comments into 'echo' calls to help debugging if the test fails.
Reported-by: Florian Westphal <fw@strlen.de> Signed-off-by: Phil Sutter <phil@nwl.cc>
Thomas Haller [Tue, 22 Aug 2023 08:13:09 +0000 (10:13 +0200)]
meta: don't assume time_t is 64 bit in date_type_print()
time_t on 32bit arch is not uint64_t. Even if it always were, it would
be ugly to make such an assumption (without a static assert). Copy the
value to a time_t variable first.
Signed-off-by: Thomas Haller <thaller@redhat.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Thomas Haller [Fri, 18 Aug 2023 14:08:19 +0000 (16:08 +0200)]
nftutils: add and use wrappers for getprotoby{name,number}_r(), getservbyport_r()
We should aim to use the thread-safe variants of getprotoby{name,number}
and getservbyport(). However, they may not be available with other libc,
so it requires a configure check. As that is cumbersome, add wrappers
that do that at one place.
These wrappers are thread-safe, if libc provides the reentrant versions.
Use them.
Signed-off-by: Thomas Haller <thaller@redhat.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Thomas Haller [Fri, 18 Aug 2023 14:33:21 +0000 (16:33 +0200)]
json: use strtok_r() instead of strtok()
strtok_r() is probably(?) everywhere available where we care.
Use it. It is thread-safe, and libnftables shouldn't make
assumptions about what other threads of the process are doing.
Signed-off-by: Thomas Haller <thaller@redhat.com> Signed-off-by: Florian Westphal <fw@strlen.de>
Florian Westphal [Tue, 15 Aug 2023 16:27:42 +0000 (18:27 +0200)]
tests: add one more chain jump in vmap test
This triggers a splat on kernels that lack 314c82841602 ("netfilter: nf_tables: can't schedule in nft_chain_validate").
There is another test case that triggers this splat
(optimize/ruleset), but that test uses some more advanced
features that don't exist on older kernels, so the splat is never seen.
Florian Westphal [Tue, 15 Aug 2023 12:26:50 +0000 (14:26 +0200)]
tests: add transaction stress test with parallel delete/add/flush and netns deletion
Based on nft_trans_stress.sh from kernel selftests, changed to run from
run-tests.sh, plus additional ideas from Pablo Neira, such as del+readd
of the netns.
Phil Sutter [Tue, 1 Aug 2023 11:35:27 +0000 (13:35 +0200)]
tests: shell: Review test-cases for destroy command
Having separate files for successful destroy of existing and
non-existing objects is a bit too much, just combine them into one.
While being at it:
* No bashisms, using /bin/sh is fine
* Append '-e' to shebang itself instead of calling 'set'
* Use 'nft -a -e' instead of assuming the created rule's handle value
* Shellcheck warned about curly braces, quote them
Jeremy Sowden [Mon, 31 Jul 2023 11:40:23 +0000 (12:40 +0100)]
py: use setup.cfg to configure setuptools
Setuptools has had support for declarative configuration for several
years. To quote their documentation:
Setuptools allows using configuration files (usually setup.cfg) to
define a package’s metadata and other options that are normally
supplied to the setup() function (declarative config).
This approach not only allows automation scenarios but also reduces
boilerplate code in some cases.
Additionally, this allows us to introduce support for PEP-517-compatible
build-systems.
Signed-off-by: Jeremy Sowden <jeremy@azazel.net> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Jeremy Sowden [Mon, 31 Jul 2023 11:40:22 +0000 (12:40 +0100)]
py: move package source into src directory
Separate the actual package source from the build files. In addition
to being a bit tidier, this will prevent setup.py being erroneously
installed when we introduce PEP-517 support in a later commit.
Signed-off-by: Jeremy Sowden <jeremy@azazel.net> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Its legal to DNAT in output and SNAT in input chain, so don't test
for that being illegal.
Fixes: 8beafab74c39 ("rule: allow src/dstnat prios in input and output") Fixes: 34ce4e4a7bb6 ("test: shell: Test cases for standard chain prios") Signed-off-by: Florian Westphal <fw@strlen.de>
Extend e0aace943412 ("libnftables: Drop cache in error case") to also
drop the cache with -c/--check, this is a dry run mode and kernel does
not get any update.
This fixes a bug with -o/--optimize, which first runs in an implicit
-c/--check mode to validate that the ruleset is correct, then it
provides the proposed optimization. In this case, if the cache is not
emptied, old objects in the cache refer to scanner data that was
already released, which triggers BUG like this:
ct expectation: fix 'list object x' vs. 'list objects in table' confusion
Just like "ct timeout", "ct expectation" is in need of the same fix,
we get segfault on "nft list ct expectation table t", if table t exists.
This is the exact same pattern as resolved for "ct timeout" in commit 1d2e22fc0521 ("ct timeout: fix 'list object x' vs. 'list objects in table' confusion").
The "dnat" command is usable from either "prerouting" or "output", but the
"dstnat" priority is only usable from "prerouting". (Likewise, "snat" is usable
from either "postrouting" or "input", but "srcnat" is only usable from
"postrouting".)
No need to restrict those priorities to pre/postrouting.
On my test vm a full scan takes almost 5s. As this would slowdown
the test runs too much, only run them every couple of tests.
This allows to detect when there is a leak reported at the
end of the script, and it allows to narrow down the test
case/group that triggers the issue.
Add new -K flag to force kmemleak runs after each test if its
available, this can then be used to find the exact test case.
meta: stash context statement length when generating payload/meta dependency
... meta mark set ip dscp
generates an implicit dependency from the inet family to match on meta
nfproto ip.
The length of this implicit expression is incorrectly adjusted to the
statement length, ie. relational to compare meta nfproto takes 4 bytes
instead of 1 byte. The evaluation of 'ip dscp' under the meta mark
statement triggers this implicit dependency which should not consider
the context statement length since it is added before the statement
itself.
This problem shows when listing the ruleset, since netlink_parse_cmp()
where left->len < right->len, hence handling the implicit dependency as
a concatenation, but it is actually a bug in the evaluation step that
leads to incorrect bytecode.
Fixes: 3c64ea7995cb ("evaluate: honor statement length in integer evaluation") Fixes: edecd58755a8 ("evaluate: support shifts larger than the width of the left operand") Tested-by: Brian Davidson <davidson.brian@gmail.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Thomas Haller [Tue, 18 Jul 2023 10:33:09 +0000 (12:33 +0200)]
py: return boolean value from Nftables.__[gs]et_output_flag()
The callers of __get_output_flag() and __set_output_flag(), for example
get_reversedns_output(), are all documented to return a "boolean" value.
Instead, they returned the underlying, non-zero flags value. That number
is not obviously useful to the caller, because there is no API so that
the caller could do anything with it (except evaluating it in a boolean
context). Adjust that, to match the documentation.
The alternative would be to update the documentation, to indicate that
the functions return a non-zero integer when the flag is set. That would
preserve the previous behavior and maybe the number could be useful
somehow(?).
Signed-off-by: Thomas Haller <thaller@redhat.com> Signed-off-by: Phil Sutter <phil@nwl.cc>
Phil Sutter [Thu, 15 Jun 2023 13:24:28 +0000 (15:24 +0200)]
Implement 'reset {set,map,element}' commands
All these are used to reset state in set/map elements, i.e. reset the
timeout or zero quota and counter values.
While 'reset element' expects a (list of) elements to be specified which
should be reset, 'reset set/map' will reset all elements in the given
set/map.
Phil Sutter [Wed, 14 Jun 2023 15:40:02 +0000 (17:40 +0200)]
evaluate: Cache looked up set for list commands
Evaluation phase checks the given table and set exist in cache. Relieve
execution phase from having to perform the lookup again by storing the
set reference in cmd->set. Just have to increase the ref counter so
cmd_free() does the right thing (which lacked handling of MAP and METER
objects for some reason).
Phil Sutter [Wed, 14 Jun 2023 13:32:04 +0000 (15:32 +0200)]
evaluate: Merge some cases in cmd_evaluate_list()
The code for set, map and meter were almost identical apart from the
specific last check. Fold them together and make the distinction in that
spot only.
Add a test to cover 423abaa40ec4 ("scanner: don't rely on fseek for
input stream repositioning") that fixes the bug described in
https://bugs.gentoo.org/675188.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Thomas Haller [Mon, 10 Jul 2023 08:45:18 +0000 (10:45 +0200)]
libnftables: inline creation of nf_sock in nft_ctx_new()
The function only has one caller. It's not clear how to extend this in a
useful way, so that it makes sense to keep the initialization in a
separate function.
Simplify the code, by inlining and dropping the static function
nft_ctx_netlink_init(). There was only one caller.
Signed-off-by: Thomas Haller <thaller@redhat.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Thomas Haller [Mon, 10 Jul 2023 08:45:16 +0000 (10:45 +0200)]
libnftables: always initialize netlink socket in nft_ctx_new()
nft_ctx_new() has a flags argument, but currently no flags are
supported. The documentation suggests to pass 0 (NFT_CTX_DEFAULT).
Initializing the netlink socket happens by default already, we should do
it for all flags. Also because nft_ctx_netlink_init() is not public
API so it's not clear how the user gets a functioning context instance
otherwise.
If we ever want to not initialize the netlink socket for a context
instance, then there should be a dedicated flag for doing that (and
additional API for making that mode of operation usable).
Signed-off-by: Thomas Haller <thaller@redhat.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
evaluate: place byteorder conversion before rshift in payload statement
For bitfield that spans more than one byte, such as ip6 dscp, byteorder
conversion needs to be done before rshift. Add unary expression for this
conversion only in the case of meta and ct statements.
Before this patch:
# nft --debug=netlink add rule ip6 x y 'meta mark set ip6 dscp'
ip6 x y
[ payload load 2b @ network header + 0 => reg 1 ]
[ bitwise reg 1 = ( reg 1 & 0x0000c00f ) ^ 0x00000000 ]
[ bitwise reg 1 = ( reg 1 >> 0x00000006 ) ]
[ byteorder reg 1 = ntoh(reg 1, 2, 2) ] <--------- incorrect
[ meta set mark with reg 1 ]
After this patch:
# nft --debug=netlink add rule ip6 x y 'meta mark set ip6 dscp'
ip6 x y
[ payload load 2b @ network header + 0 => reg 1 ]
[ bitwise reg 1 = ( reg 1 & 0x0000c00f ) ^ 0x00000000 ]
[ byteorder reg 1 = ntoh(reg 1, 2, 2) ] <-------- correct
[ bitwise reg 1 = ( reg 1 >> 0x00000006 ) ]
[ meta set mark with reg 1 ]
For the matching case, binary transfer already deals with the rshift to
adjust left and right hand side of the expression, the unary conversion
is not needed in such case.
Fixes: 8221d86e616b ("tests: py: add test-cases for ct and packet mark payload expressions") Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>