1. According to man asprintf:
If memory allocation wasn't possible, or some other error occurs,
these functions will return -1, and the contents of strp is undefined.
2. Sometimes, errp was not filled at all. In high-level code, free(errp)
will called, so segmantation fault may appear in case of error in parser
3. The most cases of using asprintf is to report about allocation fail.
So, probability of allocation of asprintf buffer is very high. And that
will lead to trash in errp.
4. For simple casses I decide to replace asprintf with strdup
On some architectures, uint64_t is defined as:
typedef unsigned long long int __u64;
on another architectures as:
typedef unsigned long int __u64;
So, according to man 3 printf,
uint64_t should be printed as "%llu" on some architectures, and as "%lu" on another. The same for scanf.
To eliminate that challenge, there is inttypes.h, in which appropriate constants
are defined for current architecture.
32-bit types (and even 16 and 8 bit types) should be printed using such constants if
printed variable defined as uint_XXXt or intXXXt type. But in reality 32-bit and less
types does not gain run-time error (except in scanf), because they pushed to stack as
32-bit values at least. So, I decide not to fix that.
I ran into a bug today related to how Linux handles a route's nexthop
flags when there is just one nexthop. Namely Linux expects the flags
to be OR'd into the rtm_flags field when there is only one nexthop and
so rtnl_route_build_msg needs to check the number of nexthops and
store the nexthops flags into this field prior to calling
nlmsg_append(...&rtmsg).
Conversely the rtnl_route_parse function needs to pull these lower
0xff bits when a single nexthop is detected.
Attached is my patch. I don't like the slight duplication of doing
the rtnl_route_get_nnexthops check twice but it seemed to be the least
turmoil of any solution I thought of.
1. Fix some places where unsigned value compared < 0
2. Fix obsolete %Z specifier to more portable %z
3. Some erroneous types substitution
4. nl_msec2str() - 64-bit msec is now properly used,
Only safe changes. I mean int <--> uint32_t and signed/unsigned fixes.
Some functinos require size_t argument instead of int, but changes of
signatures of that functions is terrible thing.
Also, I do not pretend for a full list of fixes.
Just to shut up clang -Wall -Wextra
One more thing. ifindex. I don't change that because changes will
be too big for simple fix.
Currently, rtnl_tc_handle2str understands the ingress handle but
rtnl_tc_str2handle does not. This change lets rtnl_tc_str2handle
recognize 'ingress' as a valid handle as well.
The HTB implementation in libnl uses units of microseconds in a number
of places where it seems TC is expecting time in units of ticks, which
causes actual rates much higher than requested. Additionally, libnl
uses USER_HZ for calculating buffer and cbuffer sizes, which can
result in much larger buffers than necessary on systems with high
resolution timers.
Note that the TBF qdisc uses microseconds incorrectly in two spots as
well, I fixed this but did not test.
The fw classifier allows a mask to be set, which is necessary for some
complex shaping/firewall scenarios. The attached patch adds support
for it to libnl.
- changes the modules hierarchy to better represent the set of libaries
- list the header file that needs to be included
- remove examples/doc from api ref that is included in the guide
- add references to the guide
- fix doxygen api linking for version 1.8.0
- readd doxygen mainpage to config file
- fix a couple of doxygen doc bugs
I'm using libnl in a program which I give to valgrind
in order to track memory errors / leaks. When my program
exits, it complains about non-freed memory, allocated in
3 places in classid.c, at lines 280, 284 and 289.
It seems related to the module's constructor classid_init
which allocates resources, with no destructor to free it.
The attached patch tries to fix this issue by registering
a destructor which performs the tree liberation at exit.
I found a small bug in libnl, about extended table id ( above 256 ).
Signed-off-by: Romary Sonrier <romary@sonrier.com>
Signed-off-by: Thomas Graf <tgraf@redhat.com>
The plug qdisc supports two operations - plug and unplug. When the
qdisc receives a plug ("buffer") command via netlink request,
packets arriving henceforth are buffered until a corresponding unplug
command is received. Depending on the type of unplug ("release_one"
or "release_indefinite"), the queue can be unplugged indefinitely or
selectively.
The plug qdisc allows a user to implement network output buffering
(aka output commit), used commonly in checkpoint based fault tolerance
systems. It also supports a general purpose queue plug/unplug
functionality.
The associated kernel module is available in David Miller's net-next
tree, commit: c3059be16c9ef29c05f0876a9df5fea21f29724f
This patch introduces userspace tools and API, to control the qdisc
via netlink messages.
Signed-off-by: Shriram Rajagopalan <rshriram@cs.ubc.ca>
Signed-off-by: Thomas Graf <tgraf@redhat.com>
the neighbour parsing function was previously not accessible, so
custom callback functions had to handle the decoding itself.
rtnl_neigh_parse is introduced and implemented in much the same way
as rtnl_route_parse.
Signed-off-by: Brett Ciphery <brett.ciphery@windriver.com>
Signed-off-by: Thomas Graf <tgraf@redhat.com>
In a simple test program that queries the source IP for a given
destination address I get a crash in the call to rtnl_link_alloc_cache.
Here is the stack trace (created with version 3.2.4):
Program received signal SIGSEGV, Segmentation fault.
0xb7eb7553 in strlen () from /lib/libc.so.6
(gdb) bt
#0 0xb7eb7553 in strlen () from /lib/libc.so.6
#1 0xb7eb7285 in strdup () from /lib/libc.so.6
#2 0xb7fcc305 in nla_strdup (nla=0x0) at attr.c:1033
#3 0xb7f9c173 in link_msg_parser (ops=0xb7fc2940, who=0x804b330, n=0x804c3e8, pp=0xbffffbf8) at route/link.c:486
#4 0xb7fcd485 in nl_cache_parse (ops=0xb7fc2940, who=0x804b330, nlh=0x804c3e8, params=0xbffffbf8) at cache.c:724
#5 0xb7fcd547 in update_msg_parser (msg=0x804b328, arg=0xbffffbb8) at cache.c:531
#6 0xb7fd1f25 in nl_cb_call (cb=<optimized out>, msg=<optimized out>, type=<optimized out>) at ../include/netlink-local.h:126
#7 recvmsgs (cb=<optimized out>, sk=<optimized out>) at nl.c:729
#8 nl_recvmsgs (sk=0x804b2d0, cb=0x804b368) at nl.c:780
#9 0xb7fcd5fd in __cache_pickup (sk=0x804b2d0, cache=<optimized out>, param=0xbffffbf8) at cache.c:560
#10 0xb7fcd83f in nl_cache_pickup (sk=0x804b2d0, cache=0x804b308) at cache.c:593
#11 0xb7fcd8c8 in nl_cache_refill (sk=0x804b2d0, cache=0x804b308) at cache.c:780
#12 0xb7f9d1fc in rtnl_link_alloc_cache (sk=0x804b2d0, family=4, result=0xbffffcd4) at route/link.c:868
#13 0x08048fd0 in libnl_init (data=<optimized out>) at helper_route.c:60
#14 iproute_get_source (destination=0xbffffeff "127.0.0.1",
source=0xbffffd0f "\b\004c\370\267\364_\370\267\260\224\004\b8\375\377\277e\024\347\267\320\016\377\267\273\224\004\b\364_\370\267\260\224\004\b", source_size=17)
at helper_route.c:105
#15 0x08048e6a in main (argc=2, argv=0xbffffde4) at ip_route_get.c:25
The attached patch (against 3.2.4) solves the problem, fixing something that
looks like a typo. The bug is still present in current Git master.
store type kind in rtnl_link independently. That would allow to use this
value even if type_ops are not present. This allows for example to
create devices of type unknown to libnl.
Signed-off-by: Jiri Pirko <jpirko@redhat.com>
Adds rtnl_link_enslave() / rtnl_link_release() providing a genreic
link enslaving/release API for use with all link types which use
the IFLA_MASTER property.
Only use the MULTIPATH attribute when adding routes with more than one
next hop.
This solves issues with two scenarios:
1. Adding an IPv4 route to a kernel configured without
CONFIG_IP_ROUTE_MULTIPATH=y.
2. Adding an IPv6 route in general, since the MULTIPATH attribute is not
supported there.
Signed-off-by: Michael Altizer <xiche@verizon.net>
Although it has been possible to create bonding devices, enslave and
release using the regular link API. The added API simplifies usage
and hides some of the compatibility logic.
F.e. enslave() and release() will both verify that the master assignment
has in fact been changed and return -NLE_OPNOTSUPP if it did not.
Also the API will make sure to use RTM_NEWLINK or RTM_SETLINK depending
on what is availble.
Examples are provided in src/ as nl-link-enslave.c and nl-link-release.c
As Jan Engelhardt pointed out, pktloc.c is currently licenses under the GPL
rather than the LGPL. This is a result of its previous existance in src/
which is GPL licensed. I missed to change its license when moving it to
lib/. Since I am the only contributor to the code, I am changing the license
hereby.
This patch fixes an unaligned access for IPv6. On systems with strict alignment requirements, the unaligned access will either result in garbage data or a crash.
