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.
the patch below adds the possibility to
pass user data to callbacks of type
change_func_t when using the nl_cache_mngr_*
family of functions.
If there is any better way to do this,
without duplicating the code in
cache_mngr.c please let me know.
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.
New netem-related functionality:
Added ability to save new settings to the kernel. In netem.c, the
netem_get_opts() stub has been replaced with netem_build_msg() which
manipulates the nl_msg data directly and returns an error code instead
of a new nl_msg. Modifications to qdisc_build() in qdisc.c and struct
rtnl_qdisc_ops were necessary for this.
Added support for getting/setting corruption probability/correlation.
Added support for setting a delay distribution.
Fixed tbf_msg_parser() to call tbf_alloc() instead of tbf_qdisc() to
prevent a seg fault.
Adds all missing routing attributes and brings the routing
related code to a working state. In the process the API
was broken several times with the justification that nobody
is using this code yet.
The changes include new example code which is also a prototype
for how plain CLI tools could look like to control routes.
Split the nfnetlink_log code into two seperate objects, "netfilter/log"
to represent logging instances and "netfilter/log_msg" to represent
log messages. Also perform some function name unification for consistency
with other libnl object types, mainly renaming nfnl_log_build_*_msg
to nfnl_log_build_*_request.
This changes the API in an incompatible way, but since this feature is
new and the libnl netfilter headers haven't been installed so far,
there shouldn't be any users affected by this.
Signed-off-by: Patrick McHardy <kaber@trash.net>
The NUFLA_GID attribute (currently only in net-2.6.25) contains the
gid of the sending process for locally generated packets.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Patrick McHardy reported a problem where pointers to the
payload of a netlink message as returned by f.e. the
nesting helpers become stale when the payload data
chunk is reallocated.
In order to avoid further problems, the payload chunk is
no longer extended on the fly. Instead the allocation is
made during netlink message object allocation time with
a default size of a page which should be fine for the
majority of all users. Additionally the functions
nlmsg_alloc_size() and nlmsg_set_default_size() have been
added to allocate messages of a particular length and to
modify the default message size.
This interface was internal so far which required all code defining
caches to be compiled with the sources available.
In order to simplify the interface, the co_msg_parser prototype was
changed to take the struct nl_parser_param directly instead of a
void *. It used to be void * because the co_msg_parser was directly
passed as the NL_CB_VALID callback function.
This interface was internal so far which required all code defining
objects to be compiled with the sources available.
This change exposes struct nl_object_ops which seems safe as it
is not supposed to be embedded in other structures.
Patch contains extensive documentation to help with the creation
of own object implementations.
Thomas Graf
Patrick McHardy