Phil Sutter [Fri, 12 Aug 2016 12:39:50 +0000 (14:39 +0200)]
utils: Don't return directly from SNPRINTF_BUFFER_SIZE
Apart from being a bad idea in general, the return statement contained
in that macro in some cases leads to returning from functions without
properly cleaning up, thereby causing memory leaks.
Instead, just sanitize the value in 'ret' to not harm further calls of
snprintf() (as 'len' will eventually just become zero).
Cc: Arturo Borrero <arturo.borrero.glez@gmail.com> Signed-off-by: Phil Sutter <phil@nwl.cc> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Phil Sutter [Thu, 11 Aug 2016 23:33:38 +0000 (01:33 +0200)]
src: Avoid returning uninitialized data
Although the 'err' pointer should be interesting for users only if the
parser returned non-zero, having it point to uninitialized data is
generally a bad thing.
Signed-off-by: Phil Sutter <phil@nwl.cc> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Phil Sutter [Thu, 11 Aug 2016 23:33:37 +0000 (01:33 +0200)]
common: Avoid integer overflow in nftnl_batch_is_supported()
time() may return -1 which is then assigned to an unsigned integer type
and used as sequence number. The following code increments that number
multiple times, so it may overflow and get libmnl confused. To avoid
this, fall back to a starting sequence number of zero in case the call
to time() failed.
Signed-off-by: Phil Sutter <phil@nwl.cc> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
tests: Fix tests for immediate and lookup expressions
An error at Makefile.am has caused that the tests
'nft-expr_immediate-test.c' and 'nft-expr_lookup-tests.c' have not been
compiled since they were created. This patch fix that error and some errors
in both tests.
Signed-off-by: Carlos Falgueras García <carlosfg@riseup.net> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Just in case we ever support chain with larger names in the future,
this will ensure the library doesn't break. Although I don't expect
allocating more bytes for this anytime soon, but let's be conservative
here.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
If this attribute is not supported by the library, we should rise an
assertion so the client knows something is wrong, instead of silently
going through.
The only case I can think may hit this problem is version mismatch
between library and tools. This should not ever really happen, so better
bail out from the library itself in this case.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
rule: Fix segfault due to invalid free of rule user data
If the user allocates a nftnl_udata_buf and then passes the TLV data to
nftnl_rule_set_data, the pointer stored in rule.user.data is not the
begining of the allocated block. In this situation, if it calls to
nftnl_rule_free, it tries to free this pointer and segfault is thrown.
Signed-off-by: Carlos Falgueras García <carlosfg@riseup.net> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
libnftnl: gitignore: Fix mistake in gitignore regexp
If a whole directory was ignored, files inside it will not be checked.
Fixes: f3d37ef ("libnftnl: Add to .gitignore all auto-generated files") Reported-by: Pablo Neira Ayuso <pablo@netfilter.org> Signed-off-by: Carlos Falgueras García <carlosfg@riseup.net> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Patrick McHardy [Tue, 26 Apr 2016 13:16:58 +0000 (14:16 +0100)]
libnftnl: constify object arguments to various functions
flow table support needs constant object arguments to printing functions
to avoid ugly casts. While at it, also constify object arguments to message
construction, destructor and a few helper functions.
Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Unfortunately libnftnl restricts the set names in the lookup and dynset
expressions to 16 bytes. Remove this restriction so this can work with
the upcoming 4.7 Linux kernel.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
These functions allow to create a buffer (struct nftnl_udata_buf) of
user data attributes in TLV format (struct nftnl_udata). It is inspired
by libmnl/src/attr.c. It can be used to store several TLVs sequentially
into an object.
Arturo Borrero [Tue, 13 Oct 2015 07:39:10 +0000 (09:39 +0200)]
chain: fix segfault in 'device' XML parsing
Reported by valgrind:
[...]
==14065== Process terminating with default action of signal 11 (SIGSEGV)
==14065== Access not within mapped region at address 0x0
==14065== at 0x4C2C022: strlen (vg_replace_strmem.c:454)
==14065== by 0x4E41A93: nftnl_chain_set_str (chain.c:259)
==14065== by 0x4E427F7: nftnl_mxml_chain_parse (chain.c:770)
==14065== by 0x4E48F96: nftnl_ruleset_parse_chains (ruleset.c:314)
==14065== by 0x4E4959A: nftnl_ruleset_xml_parse_ruleset (ruleset.c:625)
==14065== by 0x4E4959A: nftnl_ruleset_xml_parse_cmd (ruleset.c:668)
==14065== by 0x4E4959A: nftnl_ruleset_xml_parse (ruleset.c:706)
==14065== by 0x4E4959A: nftnl_ruleset_do_parse (ruleset.c:734)
==14065== by 0x4013C9: test_xml (nft-parsing-test.c:166)
==14065== by 0x4016F4: execute_test (nft-parsing-test.c:214)
==14065== by 0x400EBA: main (nft-parsing-test.c:330)
[...]
While at it, fix a bit the coding style.
Signed-off-by: Arturo Borrero Gonzalez <arturo.borrero.glez@gmail.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Jan Engelhardt [Wed, 16 Sep 2015 17:12:47 +0000 (19:12 +0200)]
build: bump library versioning
Commit libnftnl-1.0.3-31-g5ea54b2 removed a symbol. Such requires a
bumped to n+1:0:0. The symbol groups can be merged again to save time
processing them as the groups are relative to a particular SONAME
(of which we have a new one).
Signed-off-by: Jan Engelhardt <jengelh@inai.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This patch restores the original nft_* definitions from the header files to
avoid sudden compilation breakage of the existing clients of this library.
Then, moving forward the idea is to deprecate the old nft_* symbols anytime
soon using __attribute__((deprecated)) from the header files to warn our users
that they need to update their code.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
src: introduce nftnl_* aliases for all existing functions
This patch introduces the nftnl_ symbols as aliases for the existing nft_
symbols through the EXPORT_SYMBOL(...) macro.
We would like to use the nft_* prefix from our upcoming higher level library,
meanwhile with this move we avoid that old binaries break because of missing
symbol dependencies.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
expr: immediate: fix leak in expression destroy path
The verdict can be a chain string, make sure we release it when the expression
is destroyed. This patch adds a new nft_free_data() for this purpose and use it
from the immediate expression.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
You can fetch a pointer to the next spare area in the current page to add a new
netlink message to the batch.
void *nft_batch_buffer(struct nft_batch *batch);
Once you have added a netlink message, you have to call:
nft_batch_update(batch);
this internally updates the pointer to the next spare data area in the page.
Every page has a limit threshold after which you start using the overrun area.
page .------.
| |
| |
. . page area
| |
| |
|------|<--- limit
| |
| | overrun area
| |
'______'<--- real page size
If we write over the limit, then the next call to nft_batch_update() results in
a new empty page added to the batch. With careful page size and limit
selection, we ensure that a netlink message always fit into the page, so we
avoid the overhead of canceling the netlink message that doesn't fit in.
Once your batch is complete, if you want to send it out to kernel-space, you
can convert them to iovec via:
nft_batch_iovec(batch, iov, iov_len);
Then, after having sent the batch, you can release it via:
nft_batch_free(batch);
This class relies on the libmnl batching infrastructure.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Patrick McHardy [Sun, 12 Apr 2015 19:17:52 +0000 (20:17 +0100)]
expr: seperate expression parsing and building functions
The expression build function currently assumes to be only used from
rule context and actually builds rule attributes. Fix that and only
build the expression. Also it seems to have been exported by accident,
undo that.
Additionally, move the expression parsing function from rule parsing
and also remove any assumptions about being used in rule context.
expr/dynset.c: In function 'nft_rule_expr_dynset_json_parse':
expr/dynset.c:194:3: warning: implicit declaration of function 'nft_rule_expr_dynset_str' [-Wimplicit-function-declaration]
nft_rule_expr_dynset_str(e, NFT_EXPR_DYNSET_SET, set_name);
^
expr/dynset.c:194:31: error: 'NFT_EXPR_DYNSET_SET' undeclared (first use in this function)
nft_rule_expr_dynset_str(e, NFT_EXPR_DYNSET_SET, set_name);
^
expr/dynset.c:194:31: note: each undeclared identifier is reported only once for each function it appears in
expr/dynset.c:197:3: warning: implicit declaration of function 'nft_rule_expr_dynset_u32' [-Wimplicit-function-declaration]
nft_rule_expr_dynset_u32(e, NFT_EXPR_DYNSET_SREG, sreg);
^
expr/dynset.c:197:31: error: 'NFT_EXPR_DYNSET_SREG' undeclared (first use in this function)
nft_rule_expr_dynset_u32(e, NFT_EXPR_DYNSET_SREG, sreg);
^
expr/dynset.c:200:31: error: 'NFT_EXPR_DYNSET_DREG' undeclared (first use in this function)
nft_rule_expr_dynset_u32(e, NFT_EXPR_DYNSET_DREG, dreg);
^
expr/dynset.c: In function 'nft_rule_expr_dynset_xml_parse':
expr/dynset.c:220:31: error: 'NFT_EXPR_DYNSET_SET' undeclared (first use in this function)
nft_rule_expr_dynset_str(e, NFT_EXPR_DYNSET_SET, set_name);
^
expr/dynset.c:224:31: error: 'NFT_EXPR_DYNSET_SREG' undeclared (first use in this function)
nft_rule_expr_dynset_u32(e, NFT_EXPR_DYNSET_SREG, sreg);
^
expr/dynset.c:228:31: error: 'NFT_EXPR_DYNSET_DREG' undeclared (first use in this function)
nft_rule_expr_dynset_u32(e, NFT_EXPR_DYNSET_DREG, dreg);
^ Signed-off-by: Arturo Borrero Gonzalez <arturo.borrero.glez@gmail.com> Signed-off-by: Patrick McHardy <kaber@trash.net>