Phil Sutter [Thu, 14 Mar 2024 15:54:55 +0000 (16:54 +0100)]
obj: Return value on setters
Similar to other setters, let callers know if memory allocation fails.
Though return value with all setters, as all of them may be used to set
object type-specific attributes which may fail (e.g. if NFTNL_OBJ_TYPE
was not set before).
Phil Sutter [Fri, 15 Dec 2023 15:32:30 +0000 (16:32 +0100)]
expr: Enforce attr_policy compliance in nftnl_expr_set()
Every expression type defines an attr_policy array, so deny setting
attributes if not present. Also deny if maxlen field is non-zero and
lower than the given data_len.
Some attributes' max length is not fixed (e.g. NFTNL_EXPR_{TG,MT}_INFO )
or is not sensible to check (e.g. NFTNL_EXPR_DYNSET_EXPR). The zero
maxlen "nop" is also used for deprecated attributes, just to not
silently ignore them.
Phil Sutter [Fri, 15 Dec 2023 15:30:52 +0000 (16:30 +0100)]
expr: Introduce struct expr_ops::attr_policy
Similar to kernel's nla_policy, enable expressions to inform about
restrictions on attribute use. This allows the generic expression code
to perform sanity checks before dispatching to expression ops.
For now, this holds only the maximum data len which may be passed to
nftnl_expr_set().
While one may debate whether accepting e.g. uint32_t for sreg/dreg
attributes is correct, it is necessary to not break nftables.
Note that this introduces artificial restrictions on name lengths which
were caught by the kernel (if nftables didn't).
Phil Sutter [Wed, 13 Dec 2023 13:56:49 +0000 (14:56 +0100)]
expr: Repurpose struct expr_ops::max_attr field
Instead of holding the maximum kernel space (NFTA_*) attribute value,
use it to hold the maximum expression attribute (NFTNL_EXPR_*) value
instead. This will be used for index boundary checks in an attribute
policy array later.
set: buffer overflow in NFTNL_SET_DESC_CONCAT setter
Allow to set a maximum limit of sizeof(s->desc.field_len) which is 16
bytes, otherwise, bail out. Ensure s->desc.field_count does not go over
the array boundary.
Fixes: 7cd41b5387ac ("set: Add support for NFTA_SET_DESC_CONCAT attributes") Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Nicholas Vinson [Wed, 27 Dec 2023 03:05:17 +0000 (22:05 -0500)]
chain: Removed non-defined functions
The functions nftnl_chain_parse(), nftnl_chain_parse_file(),
nftnl_set_elems_foreach(), and nftnl_obj_unset() are no longer defined
and removed from the code.
The functions nftnl_chain_parse(), nftnl_chain_parse_file() were removed
with commit 80077787f8f2 ("src: remove json support").
The function nftnl_set_elems_foreach() does not appear to have ever been
defined.
However, libnftnl.map still lists these functions which causes libnftnl
to fail to link with ld.lld as the option --undefined-version is
disabled by default.
corubba [Sat, 9 Dec 2023 22:03:01 +0000 (23:03 +0100)]
object: getters take const struct
As with all the other entities (like table or set), the getter functions
for objects now take a `const struct nftnl_obj*` as first parameter.
The getters for all specific object types (like counter or limit), which
are called in the default switch-case, already do.
Signed-off-by: corubba <corubba@gmx.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
libnftnl support for broute meta statement introduced in:
https://patchwork.ozlabs.org/project/netfilter-devel/patch/20230224095251.11249-1-sriram.yagnaraman@est.tech/
Signed-off-by: Sriram Yagnaraman <sriram.yagnaraman@est.tech> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
The logic to build NFTA_CHAIN_HOOK enforces the presence of the hook
number and priority to include the devices. Relax this to allow for
incremental device updates.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Ian Pilcher [Tue, 18 Oct 2022 16:45:28 +0000 (11:45 -0500)]
libnftnl: Fix res_id byte order
The res_id member of struct nfgenmsg is supposed to be in network
byte order (big endian). Call htons() in __nftnl_nlmsg_build_hdr()
to ensure that this is true on little endian systems.
There is a kernel workaround that was introduced in 4.3 to address
this issue:
Jeremy Sowden [Sat, 27 Aug 2022 17:17:17 +0000 (18:17 +0100)]
rule, set_elem: fix printing of user data
Hitherto, alphanumeric characters have been printed as-is, but anything
else was replaced by '\0'. However, this effectively truncates the
output. Instead, print any printable character as-is and print anything
else as a hexadecimal escape sequence:
userdata = { \x01\x04\x01\x00\x00\x00 }
Signed-off-by: Jeremy Sowden <jeremy@azazel.net> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
When building with clang and glibc and -D_FORTIFY_SOURCE=2 is passed to
clang, the snprintf member of the expr_ops and obj_ops structures will
be incorrectly replaced with __builtin_snprintf_chk() which results in
"error: no member named '__builtin___snprintf_chk'" errors at build
time.
This patch changes the member name from 'snprintf' to 'output' to
prevent the replacement.
This bug can be emulated using GCC by undefining the __va_arg_pack macro
before stdio.h is included.
This patch is based on the notes provided in
https://bugs.gentoo.org/807766.
Signed-off-by: Nicholas Vinson <nvinson234@gmail.com> Signed-off-by: Florian Westphal <fw@strlen.de>
This patch reworks 228e8b174627 ("set_elem: Fix printing of verdict map
elements"), check if NFTNL_SET_ELEM_VERDICT is set then print the set
element verdict.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Phil Sutter [Tue, 9 Mar 2021 15:03:58 +0000 (16:03 +0100)]
ruleset: Eliminate tag and separator helpers
Those were used for JSON and XML output only with the exception of
separator helper which at the same time served as conditional nop if no
"previous" object as passed. Replace it by a string variable updated at
the end of each loop iteration and just drop the other helpers.
Phil Sutter [Tue, 9 Mar 2021 12:41:44 +0000 (13:41 +0100)]
Get rid of single option switch statements
Replace each by a conditional testing the only valid case.
There is one odd example, namely src/set.c: When printing a set with
type NFTNL_OUTPUT_XML, the relevant function would return 0 instead of
-1 like all others. Just drop it assuming nothing depends on that
(faulty) behaviour.
Cc: Arturo Borrero <arturo.borrero.glez@gmail.com> Signed-off-by: Phil Sutter <phil@nwl.cc>
Phil Sutter [Tue, 9 Mar 2021 10:26:47 +0000 (11:26 +0100)]
Drop pointless local variable in snprintf callbacks
A common idiom among snprintf callbacks was to copy the unsigned
parameter 'size' (or 'len') into a signed variable for further use.
Though since snprintf() itself casts it to unsigned and
SNPRINTF_BUFFER_SIZE() does not allow it to become negative, this is not
needed. Drop the local variable and rename the parameter accordingly.
Phil Sutter [Sat, 26 Dec 2020 18:44:48 +0000 (19:44 +0100)]
set_elem: Fix printing of verdict map elements
Elements' data was printed as type DATA_VALUE no matter the actual type.
For verdicts, this meant no printing at all (because reg->len is either
zero or garbage).
To fix this, nftnl_set_elem_snprintf_default() needs type info held in
struct nftnl_set. Pass it via parameter to that function, make it
non-static and call it from nftnl_set_snprintf_default() instead of the
generic nftnl_set_elem_snprintf(). This way no changes have to be done
to exported functions, also the output type is already defined when
nftnl_set_snprintf_default() runs so checking type value again is
pointless.
NFTNL_EXPR_DYNSET_EXPR defines the stateful expression type that
an element stores when added from the packet path.
This patch adds support for the set expression list, which generalizes
NFTNL_EXPR_DYNSET_EXPR.
This patch also adds nftnl_expr_add_expr() to add new expressions to
elements and nftnl_set_expr_expr_foreach() to iterate over the list of
expressions.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
NFTNL_SET_EXPR defines the stateful expression type that this set stores
in each element. This provides the set definition in terms of stateful
expressions. The expression that is passed via NFNTL_SET_ELEM_EXPR must
equal to this set stateful expression type, otherwise the kernel bails
out.
This patch adds support for the set expression list, which generalizes
NFTNL_SET_EXPR.
This patch also adds nftnl_set_add_expr() to add new expressions to a set
and nftnl_set_elem_expr_foreach() to iterate over the list of expressions.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
NFTNL_SET_ELEM_EXPR defines the stateful expression type that this
element stores. This is useful to restore runtime set element stateful
expressions (when saving, then reboot and restore).
This patch adds support for the set element expression list, which
generalizes NFTNL_SET_ELEM_EXPR.
This patch also adds nftnl_set_elem_add_expr() to add new expressions to
set elements and nftnl_set_elem_expr_foreach() to iterate over the list
of expressions.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Phil Sutter [Mon, 14 Dec 2020 16:53:47 +0000 (17:53 +0100)]
set_elem: Use nftnl_data_reg_snprintf()
Introduce a flag to allow toggling the '0x' prefix when printing data
values, then use the existing routines to print data registers from
set_elem code.
flowtable: relax logic to build NFTA_FLOWTABLE_HOOK
The logic to build NFTA_FLOWTABLE_HOOK enforces the presence of the hook
number and priority to include the devices. Relax this to allow for
incremental device updates.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Direct leak of 64 byte(s) in 1 object(s) allocated from:
#0 0x7f3212406518 in calloc (/usr/lib/x86_64-linux-gnu/libasan.so.5+0xe9518)
#1 0x7f321041703e in nftnl_expr_alloc /home/pablo/devel/scm/git-netfilter/libnftnl/src/expr.c:37
#2 0x7f3211d51c16 in netlink_gen_limit_stmt /home/pablo/devel/scm/git-netfilter/nftables/src/netlink_linearize.c:859
#3 0x7f3211d5220c in netlink_gen_stmt_stateful /home/pablo/devel/scm/git-netfilter/nftables/src/netlink_linearize.c:891
#4 0x7f3211d58630 in netlink_gen_meter_stmt /home/pablo/devel/scm/git-netfilter/nftables/src/netlink_linearize.c:1441
[...]
SUMMARY: AddressSanitizer: 64 byte(s) leaked in 1 allocation(s).
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Direct leak of 9 byte(s) in 1 object(s) allocated from:
#0 0x7f4e2c16b810 in strdup (/usr/lib/x86_64-linux-gnu/libasan.so.5+0x3a810)
#1 0x7f4e2a39906f in nftnl_expr_objref_set expr/objref.c:45
#2 0x7f4e2a39906f in nftnl_expr_objref_set expr/objref.c:35
Direct leak of 16 byte(s) in 2 object(s) allocated from:
#0 0x7f4018aa0810 in strdup (/usr/lib/x86_64-linux-gnu/libasan.so.5+0x3a810)
#1 0x7f4016b660af in nftnl_expr_objref_set expr/objref.c:53
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
projects / thirdparty / libnftnl.git / log
