With support for socket option SO_PROTOCOL we don't need the protocol
argument to nl_socket_set_fd(). Maybe we should drop the protocol argument
and just not support nl_socket_set_fd() on older systems. But instead
keep the argument and allow passing -1 to autodetect it.
If the user sets a protocol option, we check via getsockopt() that the
value is correct and error out otherwise.
On older kernels, the user must set the value. Otherwise
nl_socket_set_fd() will fail.
Signed-off-by: Thomas Haller <thaller@redhat.com>
This is based on the patch by sagil@infinidat.com, but heavily modified.
Add a function nl_socket_set_fd(), I renamed it from nl_connect_fd().
Now nl_connect() and nl_socket_set_fd() are implemented independently as
they share little code. But they have similar functionality:
to initialize a libnl socket and set it's file descriptor.
A user who wants libnl to setup the socket can continue to use nl_connect().
A user with special requirements should setup the socket entirely. That includes
calling socket() (with or without SOCK_CLOEXEC), bind(), setting buffer size.
For the same reason I dropped nl_create_fd(). It didn't do much more then
calling socket() -- which the user can do directly.
https://github.com/thom311/libnl/pull/68
Signed-off-by: Thomas Haller <thaller@redhat.com>
- Added option to create socket (fd) without bind.
It is now possible to forward the socket fd to another child process...
...later use nl_connect_fd() to connect to socket from the child process.
- Added option to disable CLOEXEC even if defined (in socket.h)
'nl_socket_enable_cloexec' & 'nl_socket_disable_cloexec'
No change to current default behavior.
Signed-off-by: Sagi Lowenhardt <sagil@infinidat.com>
The flag was not actually used.
NL_SOCK_BUFSIZE_SET was only set by nl_socket_set_buffer_size().
Note that you can only call nl_socket_set_buffer_size() on a socket that
is already connected via nl_connect().
On first call, nl_connect() would always see NL_SOCK_BUFSIZE_SET unset, and
call nl_socket_set_buffer_size().
Since the flag was never unset, when trying to connect a socket a second
time, we would not set the buffer size again. Which was a bug.
Signed-off-by: Thomas Haller <thaller@redhat.com>
nl_syserr2nlerr() reduces a lot of platform errors to NLE_FAILURE --
"Unspecific failure" which makes it somehow hard to track down the real reason
behind a failure.
Logging them with level of 4 makes it a little less painful.
https://github.com/thom311/libnl/pull/65
Signed-off-by: Thomas Haller <thaller@redhat.com>
Instead of always trying the same order of ports when
looking for an unused port, randomize the order (naively).
As libnl-1 uses the same function, it is likely that two applications
that are using both libraries generate the same ports. By chosing a
different order how to select the local port, the chances are smaller
for this to happen (however, it cannot avoid it entirely. The user
and/or libnl3 still has to cope with the situation, that somebody
else might already use the port).
Signed-off-by: Thomas Haller <thaller@redhat.com>
It can easily happen that the generated local netlink port is alrady in
use. In that case bind will fail with ADDRINUSE.
Users of libnl3 could workaround this, by managing the local ports
themselves, but sometimes these users are libraries too and they also
don't know which ports might be used by other components.
This patch changes that nl_socket_alloc() no longer initilizes the local
port id immediately. Instead it will be initialized when the user calls
nl_socket_get_local_port() the first time and thereby shows interest in
the value.
If bind() fails with ADDRINUSE, check if the user ever cared about the
local port, i.e. whether the local port is still unset. If it is still
unset, assume that libnl should choose a suitable port and retry until
an unused port can be found.
Signed-off-by: Thomas Haller <thaller@redhat.com>
By failing inside of nl_socket_alloc(), the user can not even work around
when running out of local ports. This patch changes that if there are no more
local ports, we set the port to UINT32_MAX. This is a consistent behavior
to calling nl_socket_set_local_port(sk, 0).
In general, since nl_socket_set_local_port() does not restict the generated
ports in any way we cannot assume to have a valid port. So the check in
the constructor was harmful and users who ever encountered it (because they
created 1024 libnl3 sockets) could not even work around it.
Acked-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: Thomas Haller <thaller@redhat.com>
This was a bug on architectures with native int type less then 32 bit.
Acked-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: Thomas Haller <thaller@redhat.com>
- each *_get() should have corresponding *_put(). That rule was broken in nl_socket_alloc()
- Also, check if cb is NULL in nl_socket_set_cb (calls BUG())
- 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've found a bug in the following scenario (fragment of code):
while (1) {
struct nl_sock *sk = nl_socket_alloc();
if (sk == NULL) {
fprintf(stderr, "Failed to allocate nl socket\n");
break;
}
nl_socket_set_local_port(sk, 0);
nl_socket_free(sk);
}
The problem is that nl_socket_set_local_port(, 0) does not
release local port if it is allocated before.
This patch has been in Fedora and RHEL for a while. It adds a mutex
to protect the port map from concurrent thread accesses.
Original patch from Stefan Berger <stefanb@us.ibm.com>.
Modified to use configure.in to check for libpthread
I have a patch against commit d378220c96
extending libnl with a facility to receive generic netlink messages sent
to multicast groups.
Essentially it add one new function genl_ctrl_resolve_grp which
prototype looks like this
int genl_ctrl_resolve_grp(struct nl_sock *sk, const char *family_name,
const char *grp_name)
It resolves the family name and the group name to group id. Then
the returned id can be used in nl_socket_add_membership to subscribe
to multicast messages.
Besides that it adds two more functions
uint32_t nl_socket_get_peer_groups(struct nl_sock *sk)
void nl_socket_set_peer_groups(struct nl_sock *sk, uint32_t groups)
allowing to modify the socket peer groups field. So it's possible to
multicast messages from the user space using the legacy interface.
Looks like there is no way (or I was not able to find one?) to modify
the netlink socket destination group from the user space, when the
group id is greater then 32.
Current calculation is always off, not reflecting the right position
in the bitmap, which results in failures due to conflicts (detected at
the kernel level) when trying to open a new handle.
Signed-off-by: Inaky Perez-Gonzalez <inaky@linux.intel.com>
Instead of calling the membership functions several times it is
helpfull to extend the API and make the single group functions a
special case.
The value 0 (NFNLGRP_NONE) terminates this list.
Example use:
nl_socket_add_memberships(sock, group_1, group_2, 0);
nl_socket_drop_memberships(sock, group_1, group_2, 0);
Signed-off-by: Holger Eitzenberger <holger@eitzenberger.org>
The idea of a common handle is long revised and only misleading,
nl_handle really represents a socket with some additional
action handlers assigned to it.
Alias for nl_handle is kept for backwards compatibility.
In order for the interface to become more thread safe, the error
handling was revised to no longer depend on a static errno and
error string buffer.
This patch converts all error paths to return a libnl specific
error code which can be translated to a error message using
nl_geterror(int error). The functions nl_error() and
nl_get_errno() are therefore obsolete.
This change required various sets of function prototypes to be
changed in order to return an error code, the most prominent
are:
struct nl_cache *foo_alloc_cache(...);
changed to:
int foo_alloc_cache(..., struct nl_cache **);
struct nl_msg *foo_build_request(...);
changed to:
int foo_build_request(..., struct nl_msg **);
struct foo *foo_parse(...);
changed to:
int foo_parse(..., struct foo **);
This pretty much only leaves trivial allocation functions to
still return a pointer object which can still return NULL to
signal out of memory.
This change is a serious API and ABI breaker, sorry!
Fixes an off-by-one when releasing local ports. Fixes nl_connect()
to properly close the socket upon failure. Return EBADFD if
operations are performed on unconnected sockets where appropriate.
Makes nl_handle_alloc() return an error if all local ports are
used up.