linux/net/ieee802154/netlink.c
Johannes Berg 2a94fe48f3 genetlink: make multicast groups const, prevent abuse
Register generic netlink multicast groups as an array with
the family and give them contiguous group IDs. Then instead
of passing the global group ID to the various functions that
send messages, pass the ID relative to the family - for most
families that's just 0 because the only have one group.

This avoids the list_head and ID in each group, adding a new
field for the mcast group ID offset to the family.

At the same time, this allows us to prevent abusing groups
again like the quota and dropmon code did, since we can now
check that a family only uses a group it owns.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-11-19 16:39:06 -05:00

145 lines
3.7 KiB
C

/*
* Netlink inteface for IEEE 802.15.4 stack
*
* Copyright 2007, 2008 Siemens AG
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2
* as published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Written by:
* Sergey Lapin <slapin@ossfans.org>
* Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
* Maxim Osipov <maxim.osipov@siemens.com>
*/
#include <linux/kernel.h>
#include <linux/gfp.h>
#include <net/genetlink.h>
#include <linux/nl802154.h>
#include "ieee802154.h"
static unsigned int ieee802154_seq_num;
static DEFINE_SPINLOCK(ieee802154_seq_lock);
struct genl_family nl802154_family = {
.id = GENL_ID_GENERATE,
.hdrsize = 0,
.name = IEEE802154_NL_NAME,
.version = 1,
.maxattr = IEEE802154_ATTR_MAX,
};
/* Requests to userspace */
struct sk_buff *ieee802154_nl_create(int flags, u8 req)
{
void *hdr;
struct sk_buff *msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_ATOMIC);
unsigned long f;
if (!msg)
return NULL;
spin_lock_irqsave(&ieee802154_seq_lock, f);
hdr = genlmsg_put(msg, 0, ieee802154_seq_num++,
&nl802154_family, flags, req);
spin_unlock_irqrestore(&ieee802154_seq_lock, f);
if (!hdr) {
nlmsg_free(msg);
return NULL;
}
return msg;
}
int ieee802154_nl_mcast(struct sk_buff *msg, unsigned int group)
{
struct nlmsghdr *nlh = nlmsg_hdr(msg);
void *hdr = genlmsg_data(nlmsg_data(nlh));
if (genlmsg_end(msg, hdr) < 0)
goto out;
return genlmsg_multicast(&nl802154_family, msg, 0, group, GFP_ATOMIC);
out:
nlmsg_free(msg);
return -ENOBUFS;
}
struct sk_buff *ieee802154_nl_new_reply(struct genl_info *info,
int flags, u8 req)
{
void *hdr;
struct sk_buff *msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_ATOMIC);
if (!msg)
return NULL;
hdr = genlmsg_put_reply(msg, info,
&nl802154_family, flags, req);
if (!hdr) {
nlmsg_free(msg);
return NULL;
}
return msg;
}
int ieee802154_nl_reply(struct sk_buff *msg, struct genl_info *info)
{
struct nlmsghdr *nlh = nlmsg_hdr(msg);
void *hdr = genlmsg_data(nlmsg_data(nlh));
if (genlmsg_end(msg, hdr) < 0)
goto out;
return genlmsg_reply(msg, info);
out:
nlmsg_free(msg);
return -ENOBUFS;
}
static const struct genl_ops ieee8021154_ops[] = {
/* see nl-phy.c */
IEEE802154_DUMP(IEEE802154_LIST_PHY, ieee802154_list_phy,
ieee802154_dump_phy),
IEEE802154_OP(IEEE802154_ADD_IFACE, ieee802154_add_iface),
IEEE802154_OP(IEEE802154_DEL_IFACE, ieee802154_del_iface),
/* see nl-mac.c */
IEEE802154_OP(IEEE802154_ASSOCIATE_REQ, ieee802154_associate_req),
IEEE802154_OP(IEEE802154_ASSOCIATE_RESP, ieee802154_associate_resp),
IEEE802154_OP(IEEE802154_DISASSOCIATE_REQ, ieee802154_disassociate_req),
IEEE802154_OP(IEEE802154_SCAN_REQ, ieee802154_scan_req),
IEEE802154_OP(IEEE802154_START_REQ, ieee802154_start_req),
IEEE802154_DUMP(IEEE802154_LIST_IFACE, ieee802154_list_iface,
ieee802154_dump_iface),
};
static const struct genl_multicast_group ieee802154_mcgrps[] = {
[IEEE802154_COORD_MCGRP] = { .name = IEEE802154_MCAST_COORD_NAME, },
[IEEE802154_BEACON_MCGRP] = { .name = IEEE802154_MCAST_BEACON_NAME, },
};
int __init ieee802154_nl_init(void)
{
return genl_register_family_with_ops_groups(&nl802154_family,
ieee8021154_ops,
ieee802154_mcgrps);
}
void __exit ieee802154_nl_exit(void)
{
genl_unregister_family(&nl802154_family);
}