linux/net/ieee802154/dgram.c
Phoebe Buckheister af9eed5bbf ieee802154: add dgram sockopts for security control
Allow datagram sockets to override the security settings of the device
they send from on a per-socket basis. Requires CAP_NET_ADMIN or
CAP_NET_RAW, since raw sockets can send arbitrary packets anyway.

Signed-off-by: Phoebe Buckheister <phoebe.buckheister@itwm.fraunhofer.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-05-16 17:23:41 -04:00

553 lines
11 KiB
C

/*
* IEEE 802.15.4 dgram socket interface
*
* 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>
*/
#include <linux/capability.h>
#include <linux/net.h>
#include <linux/module.h>
#include <linux/if_arp.h>
#include <linux/list.h>
#include <linux/slab.h>
#include <net/sock.h>
#include <net/af_ieee802154.h>
#include <net/ieee802154.h>
#include <net/ieee802154_netdev.h>
#include <asm/ioctls.h>
#include "af802154.h"
static HLIST_HEAD(dgram_head);
static DEFINE_RWLOCK(dgram_lock);
struct dgram_sock {
struct sock sk;
struct ieee802154_addr src_addr;
struct ieee802154_addr dst_addr;
unsigned int bound:1;
unsigned int connected:1;
unsigned int want_ack:1;
unsigned int secen:1;
unsigned int secen_override:1;
unsigned int seclevel:3;
unsigned int seclevel_override:1;
};
static inline struct dgram_sock *dgram_sk(const struct sock *sk)
{
return container_of(sk, struct dgram_sock, sk);
}
static void dgram_hash(struct sock *sk)
{
write_lock_bh(&dgram_lock);
sk_add_node(sk, &dgram_head);
sock_prot_inuse_add(sock_net(sk), sk->sk_prot, 1);
write_unlock_bh(&dgram_lock);
}
static void dgram_unhash(struct sock *sk)
{
write_lock_bh(&dgram_lock);
if (sk_del_node_init(sk))
sock_prot_inuse_add(sock_net(sk), sk->sk_prot, -1);
write_unlock_bh(&dgram_lock);
}
static int dgram_init(struct sock *sk)
{
struct dgram_sock *ro = dgram_sk(sk);
ro->want_ack = 1;
return 0;
}
static void dgram_close(struct sock *sk, long timeout)
{
sk_common_release(sk);
}
static int dgram_bind(struct sock *sk, struct sockaddr *uaddr, int len)
{
struct sockaddr_ieee802154 *addr = (struct sockaddr_ieee802154 *)uaddr;
struct ieee802154_addr haddr;
struct dgram_sock *ro = dgram_sk(sk);
int err = -EINVAL;
struct net_device *dev;
lock_sock(sk);
ro->bound = 0;
if (len < sizeof(*addr))
goto out;
if (addr->family != AF_IEEE802154)
goto out;
ieee802154_addr_from_sa(&haddr, &addr->addr);
dev = ieee802154_get_dev(sock_net(sk), &haddr);
if (!dev) {
err = -ENODEV;
goto out;
}
if (dev->type != ARPHRD_IEEE802154) {
err = -ENODEV;
goto out_put;
}
ro->src_addr = haddr;
ro->bound = 1;
err = 0;
out_put:
dev_put(dev);
out:
release_sock(sk);
return err;
}
static int dgram_ioctl(struct sock *sk, int cmd, unsigned long arg)
{
switch (cmd) {
case SIOCOUTQ:
{
int amount = sk_wmem_alloc_get(sk);
return put_user(amount, (int __user *)arg);
}
case SIOCINQ:
{
struct sk_buff *skb;
unsigned long amount;
amount = 0;
spin_lock_bh(&sk->sk_receive_queue.lock);
skb = skb_peek(&sk->sk_receive_queue);
if (skb != NULL) {
/*
* We will only return the amount
* of this packet since that is all
* that will be read.
*/
amount = skb->len - ieee802154_hdr_length(skb);
}
spin_unlock_bh(&sk->sk_receive_queue.lock);
return put_user(amount, (int __user *)arg);
}
}
return -ENOIOCTLCMD;
}
/* FIXME: autobind */
static int dgram_connect(struct sock *sk, struct sockaddr *uaddr,
int len)
{
struct sockaddr_ieee802154 *addr = (struct sockaddr_ieee802154 *)uaddr;
struct dgram_sock *ro = dgram_sk(sk);
int err = 0;
if (len < sizeof(*addr))
return -EINVAL;
if (addr->family != AF_IEEE802154)
return -EINVAL;
lock_sock(sk);
if (!ro->bound) {
err = -ENETUNREACH;
goto out;
}
ieee802154_addr_from_sa(&ro->dst_addr, &addr->addr);
ro->connected = 1;
out:
release_sock(sk);
return err;
}
static int dgram_disconnect(struct sock *sk, int flags)
{
struct dgram_sock *ro = dgram_sk(sk);
lock_sock(sk);
ro->connected = 0;
release_sock(sk);
return 0;
}
static int dgram_sendmsg(struct kiocb *iocb, struct sock *sk,
struct msghdr *msg, size_t size)
{
struct net_device *dev;
unsigned int mtu;
struct sk_buff *skb;
struct ieee802154_mac_cb *cb;
struct dgram_sock *ro = dgram_sk(sk);
struct ieee802154_addr dst_addr;
int hlen, tlen;
int err;
if (msg->msg_flags & MSG_OOB) {
pr_debug("msg->msg_flags = 0x%x\n", msg->msg_flags);
return -EOPNOTSUPP;
}
if (!ro->connected && !msg->msg_name)
return -EDESTADDRREQ;
else if (ro->connected && msg->msg_name)
return -EISCONN;
if (!ro->bound)
dev = dev_getfirstbyhwtype(sock_net(sk), ARPHRD_IEEE802154);
else
dev = ieee802154_get_dev(sock_net(sk), &ro->src_addr);
if (!dev) {
pr_debug("no dev\n");
err = -ENXIO;
goto out;
}
mtu = dev->mtu;
pr_debug("name = %s, mtu = %u\n", dev->name, mtu);
if (size > mtu) {
pr_debug("size = %Zu, mtu = %u\n", size, mtu);
err = -EMSGSIZE;
goto out_dev;
}
hlen = LL_RESERVED_SPACE(dev);
tlen = dev->needed_tailroom;
skb = sock_alloc_send_skb(sk, hlen + tlen + size,
msg->msg_flags & MSG_DONTWAIT,
&err);
if (!skb)
goto out_dev;
skb_reserve(skb, hlen);
skb_reset_network_header(skb);
cb = mac_cb_init(skb);
cb->type = IEEE802154_FC_TYPE_DATA;
cb->ackreq = ro->want_ack;
if (msg->msg_name) {
DECLARE_SOCKADDR(struct sockaddr_ieee802154*, daddr, msg->msg_name);
ieee802154_addr_from_sa(&dst_addr, &daddr->addr);
} else {
dst_addr = ro->dst_addr;
}
cb->secen = ro->secen;
cb->secen_override = ro->secen_override;
cb->seclevel = ro->seclevel;
cb->seclevel_override = ro->seclevel_override;
err = dev_hard_header(skb, dev, ETH_P_IEEE802154, &dst_addr,
ro->bound ? &ro->src_addr : NULL, size);
if (err < 0)
goto out_skb;
err = memcpy_fromiovec(skb_put(skb, size), msg->msg_iov, size);
if (err < 0)
goto out_skb;
skb->dev = dev;
skb->sk = sk;
skb->protocol = htons(ETH_P_IEEE802154);
dev_put(dev);
err = dev_queue_xmit(skb);
if (err > 0)
err = net_xmit_errno(err);
return err ?: size;
out_skb:
kfree_skb(skb);
out_dev:
dev_put(dev);
out:
return err;
}
static int dgram_recvmsg(struct kiocb *iocb, struct sock *sk,
struct msghdr *msg, size_t len, int noblock, int flags,
int *addr_len)
{
size_t copied = 0;
int err = -EOPNOTSUPP;
struct sk_buff *skb;
DECLARE_SOCKADDR(struct sockaddr_ieee802154 *, saddr, msg->msg_name);
skb = skb_recv_datagram(sk, flags, noblock, &err);
if (!skb)
goto out;
copied = skb->len;
if (len < copied) {
msg->msg_flags |= MSG_TRUNC;
copied = len;
}
/* FIXME: skip headers if necessary ?! */
err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);
if (err)
goto done;
sock_recv_ts_and_drops(msg, sk, skb);
if (saddr) {
saddr->family = AF_IEEE802154;
ieee802154_addr_to_sa(&saddr->addr, &mac_cb(skb)->source);
*addr_len = sizeof(*saddr);
}
if (flags & MSG_TRUNC)
copied = skb->len;
done:
skb_free_datagram(sk, skb);
out:
if (err)
return err;
return copied;
}
static int dgram_rcv_skb(struct sock *sk, struct sk_buff *skb)
{
skb = skb_share_check(skb, GFP_ATOMIC);
if (!skb)
return NET_RX_DROP;
if (sock_queue_rcv_skb(sk, skb) < 0) {
kfree_skb(skb);
return NET_RX_DROP;
}
return NET_RX_SUCCESS;
}
static inline bool
ieee802154_match_sock(__le64 hw_addr, __le16 pan_id, __le16 short_addr,
struct dgram_sock *ro)
{
if (!ro->bound)
return true;
if (ro->src_addr.mode == IEEE802154_ADDR_LONG &&
hw_addr == ro->src_addr.extended_addr)
return true;
if (ro->src_addr.mode == IEEE802154_ADDR_SHORT &&
pan_id == ro->src_addr.pan_id &&
short_addr == ro->src_addr.short_addr)
return true;
return false;
}
int ieee802154_dgram_deliver(struct net_device *dev, struct sk_buff *skb)
{
struct sock *sk, *prev = NULL;
int ret = NET_RX_SUCCESS;
__le16 pan_id, short_addr;
__le64 hw_addr;
/* Data frame processing */
BUG_ON(dev->type != ARPHRD_IEEE802154);
pan_id = ieee802154_mlme_ops(dev)->get_pan_id(dev);
short_addr = ieee802154_mlme_ops(dev)->get_short_addr(dev);
hw_addr = ieee802154_devaddr_from_raw(dev->dev_addr);
read_lock(&dgram_lock);
sk_for_each(sk, &dgram_head) {
if (ieee802154_match_sock(hw_addr, pan_id, short_addr,
dgram_sk(sk))) {
if (prev) {
struct sk_buff *clone;
clone = skb_clone(skb, GFP_ATOMIC);
if (clone)
dgram_rcv_skb(prev, clone);
}
prev = sk;
}
}
if (prev)
dgram_rcv_skb(prev, skb);
else {
kfree_skb(skb);
ret = NET_RX_DROP;
}
read_unlock(&dgram_lock);
return ret;
}
static int dgram_getsockopt(struct sock *sk, int level, int optname,
char __user *optval, int __user *optlen)
{
struct dgram_sock *ro = dgram_sk(sk);
int val, len;
if (level != SOL_IEEE802154)
return -EOPNOTSUPP;
if (get_user(len, optlen))
return -EFAULT;
len = min_t(unsigned int, len, sizeof(int));
switch (optname) {
case WPAN_WANTACK:
val = ro->want_ack;
break;
case WPAN_SECURITY:
if (!ro->secen_override)
val = WPAN_SECURITY_DEFAULT;
else if (ro->secen)
val = WPAN_SECURITY_ON;
else
val = WPAN_SECURITY_OFF;
break;
case WPAN_SECURITY_LEVEL:
if (!ro->seclevel_override)
val = WPAN_SECURITY_LEVEL_DEFAULT;
else
val = ro->seclevel;
break;
default:
return -ENOPROTOOPT;
}
if (put_user(len, optlen))
return -EFAULT;
if (copy_to_user(optval, &val, len))
return -EFAULT;
return 0;
}
static int dgram_setsockopt(struct sock *sk, int level, int optname,
char __user *optval, unsigned int optlen)
{
struct dgram_sock *ro = dgram_sk(sk);
struct net *net = sock_net(sk);
int val;
int err = 0;
if (optlen < sizeof(int))
return -EINVAL;
if (get_user(val, (int __user *)optval))
return -EFAULT;
lock_sock(sk);
switch (optname) {
case WPAN_WANTACK:
ro->want_ack = !!val;
break;
case WPAN_SECURITY:
if (!ns_capable(net->user_ns, CAP_NET_ADMIN) &&
!ns_capable(net->user_ns, CAP_NET_RAW)) {
err = -EPERM;
break;
}
switch (val) {
case WPAN_SECURITY_DEFAULT:
ro->secen_override = 0;
break;
case WPAN_SECURITY_ON:
ro->secen_override = 1;
ro->secen = 1;
break;
case WPAN_SECURITY_OFF:
ro->secen_override = 1;
ro->secen = 0;
break;
default:
err = -EINVAL;
break;
}
break;
case WPAN_SECURITY_LEVEL:
if (!ns_capable(net->user_ns, CAP_NET_ADMIN) &&
!ns_capable(net->user_ns, CAP_NET_RAW)) {
err = -EPERM;
break;
}
if (val < WPAN_SECURITY_LEVEL_DEFAULT ||
val > IEEE802154_SCF_SECLEVEL_ENC_MIC128) {
err = -EINVAL;
} else if (val == WPAN_SECURITY_LEVEL_DEFAULT) {
ro->seclevel_override = 0;
} else {
ro->seclevel_override = 1;
ro->seclevel = val;
}
break;
default:
err = -ENOPROTOOPT;
break;
}
release_sock(sk);
return err;
}
struct proto ieee802154_dgram_prot = {
.name = "IEEE-802.15.4-MAC",
.owner = THIS_MODULE,
.obj_size = sizeof(struct dgram_sock),
.init = dgram_init,
.close = dgram_close,
.bind = dgram_bind,
.sendmsg = dgram_sendmsg,
.recvmsg = dgram_recvmsg,
.hash = dgram_hash,
.unhash = dgram_unhash,
.connect = dgram_connect,
.disconnect = dgram_disconnect,
.ioctl = dgram_ioctl,
.getsockopt = dgram_getsockopt,
.setsockopt = dgram_setsockopt,
};