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af_packet.c
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/*
* INET An implementation of the TCP/IP protocol suite for the LINUX
* operating system. INET is implemented using the BSD Socket
* interface as the means of communication with the user level.
*
* PACKET - implements raw packet sockets.
*
* Version: $Id: af_packet.c,v 1.61 2002/02/08 03:57:19 davem Exp $
*
* Authors: Ross Biro
* Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
* Alan Cox, <gw4pts@gw4pts.ampr.org>
*
* Fixes:
* Alan Cox : verify_area() now used correctly
* Alan Cox : new skbuff lists, look ma no backlogs!
* Alan Cox : tidied skbuff lists.
* Alan Cox : Now uses generic datagram routines I
* added. Also fixed the peek/read crash
* from all old Linux datagram code.
* Alan Cox : Uses the improved datagram code.
* Alan Cox : Added NULL's for socket options.
* Alan Cox : Re-commented the code.
* Alan Cox : Use new kernel side addressing
* Rob Janssen : Correct MTU usage.
* Dave Platt : Counter leaks caused by incorrect
* interrupt locking and some slightly
* dubious gcc output. Can you read
* compiler: it said _VOLATILE_
* Richard Kooijman : Timestamp fixes.
* Alan Cox : New buffers. Use sk->mac.raw.
* Alan Cox : sendmsg/recvmsg support.
* Alan Cox : Protocol setting support
* Alexey Kuznetsov : Untied from IPv4 stack.
* Cyrus Durgin : Fixed kerneld for kmod.
* Michal Ostrowski : Module initialization cleanup.
* Ulises Alonso : Frame number limit removal and
* packet_set_ring memory leak.
* Eric Biederman : Allow for > 8 byte hardware addresses.
* The convention is that longer addresses
* will simply extend the hardware address
* byte arrays at the end of sockaddr_ll
* and packet_mreq.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*
*/
#include <linux/config.h>
#include <linux/types.h>
#include <linux/sched.h>
#include <linux/mm.h>
#include <linux/capability.h>
#include <linux/fcntl.h>
#include <linux/socket.h>
#include <linux/in.h>
#include <linux/inet.h>
#include <linux/netdevice.h>
#include <linux/if_packet.h>
#include <linux/wireless.h>
#include <linux/kmod.h>
#include <net/ip.h>
#include <net/protocol.h>
#include <linux/skbuff.h>
#include <net/sock.h>
#include <linux/errno.h>
#include <linux/timer.h>
#include <asm/system.h>
#include <asm/uaccess.h>
#include <asm/ioctls.h>
#include <asm/page.h>
#include <asm/io.h>
#include <linux/proc_fs.h>
#include <linux/seq_file.h>
#include <linux/poll.h>
#include <linux/module.h>
#include <linux/init.h>
#ifdef CONFIG_INET
#include <net/inet_common.h>
#endif
#define CONFIG_SOCK_PACKET 1
/*
Proposed replacement for SIOC{ADD,DEL}MULTI and
IFF_PROMISC, IFF_ALLMULTI flags.
It is more expensive, but I believe,
it is really correct solution: reentereble, safe and fault tolerant.
IFF_PROMISC/IFF_ALLMULTI/SIOC{ADD/DEL}MULTI are faked by keeping
reference count and global flag, so that real status is
(gflag|(count != 0)), so that we can use obsolete faulty interface
not harming clever users.
*/
#define CONFIG_PACKET_MULTICAST 1
/*
Assumptions:
- if device has no dev->hard_header routine, it adds and removes ll header
inside itself. In this case ll header is invisible outside of device,
but higher levels still should reserve dev->hard_header_len.
Some devices are enough clever to reallocate skb, when header
will not fit to reserved space (tunnel), another ones are silly
(PPP).
- packet socket receives packets with pulled ll header,
so that SOCK_RAW should push it back.
On receive:
-----------
Incoming, dev->hard_header!=NULL
mac.raw -> ll header
data -> data
Outgoing, dev->hard_header!=NULL
mac.raw -> ll header
data -> ll header
Incoming, dev->hard_header==NULL
mac.raw -> UNKNOWN position. It is very likely, that it points to ll header.
PPP makes it, that is wrong, because introduce assymetry
between rx and tx paths.
data -> data
Outgoing, dev->hard_header==NULL
mac.raw -> data. ll header is still not built!
data -> data
Resume
If dev->hard_header==NULL we are unlikely to restore sensible ll header.
On transmit:
------------
dev->hard_header != NULL
mac.raw -> ll header
data -> ll header
dev->hard_header == NULL (ll header is added by device, we cannot control it)
mac.raw -> data
data -> data
We should set nh.raw on output to correct posistion,
packet classifier depends on it.
*/
/* List of all packet sockets. */
static HLIST_HEAD(packet_sklist);
static DEFINE_RWLOCK(packet_sklist_lock);
static atomic_t packet_socks_nr;
/* Private packet socket structures. */
#ifdef CONFIG_PACKET_MULTICAST
struct packet_mclist
{
struct packet_mclist *next;
int ifindex;
int count;
unsigned short type;
unsigned short alen;
unsigned char addr[MAX_ADDR_LEN];
};
/* identical to struct packet_mreq except it has
* a longer address field.
*/
struct packet_mreq_max
{
int mr_ifindex;
unsigned short mr_type;
unsigned short mr_alen;
unsigned char mr_address[MAX_ADDR_LEN];
};
#endif
#ifdef CONFIG_PACKET_MMAP
static int packet_set_ring(struct sock *sk, struct tpacket_req *req, int closing);
#endif
static void packet_flush_mclist(struct sock *sk);
struct packet_sock {
/* struct sock has to be the first member of packet_sock */
struct sock sk;
struct tpacket_stats stats;
#ifdef CONFIG_PACKET_MMAP
char * *pg_vec;
unsigned int head;
unsigned int frames_per_block;
unsigned int frame_size;
unsigned int frame_max;
int copy_thresh;
#endif
struct packet_type prot_hook;
spinlock_t bind_lock;
char running; /* prot_hook is attached*/
int ifindex; /* bound device */
unsigned short num;
#ifdef CONFIG_PACKET_MULTICAST
struct packet_mclist *mclist;
#endif
#ifdef CONFIG_PACKET_MMAP
atomic_t mapped;
unsigned int pg_vec_order;
unsigned int pg_vec_pages;
unsigned int pg_vec_len;
#endif
};
#ifdef CONFIG_PACKET_MMAP
static inline char *packet_lookup_frame(struct packet_sock *po, unsigned int position)
{
unsigned int pg_vec_pos, frame_offset;
char *frame;
pg_vec_pos = position / po->frames_per_block;
frame_offset = position % po->frames_per_block;
frame = po->pg_vec[pg_vec_pos] + (frame_offset * po->frame_size);
return frame;
}
#endif
static inline struct packet_sock *pkt_sk(struct sock *sk)
{
return (struct packet_sock *)sk;
}
static void packet_sock_destruct(struct sock *sk)
{
BUG_TRAP(!atomic_read(&sk->sk_rmem_alloc));
BUG_TRAP(!atomic_read(&sk->sk_wmem_alloc));
if (!sock_flag(sk, SOCK_DEAD)) {
printk("Attempt to release alive packet socket: %p\n", sk);
return;
}
atomic_dec(&packet_socks_nr);
#ifdef PACKET_REFCNT_DEBUG
printk(KERN_DEBUG "PACKET socket %p is free, %d are alive\n", sk, atomic_read(&packet_socks_nr));
#endif
}
static const struct proto_ops packet_ops;
#ifdef CONFIG_SOCK_PACKET
static const struct proto_ops packet_ops_spkt;
static int packet_rcv_spkt(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev)
{
struct sock *sk;
struct sockaddr_pkt *spkt;
/*
* When we registered the protocol we saved the socket in the data
* field for just this event.
*/
sk = pt->af_packet_priv;
/*
* Yank back the headers [hope the device set this
* right or kerboom...]
*
* Incoming packets have ll header pulled,
* push it back.
*
* For outgoing ones skb->data == skb->mac.raw
* so that this procedure is noop.
*/
if (skb->pkt_type == PACKET_LOOPBACK)
goto out;
if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL)
goto oom;
/* drop any routing info */
dst_release(skb->dst);
skb->dst = NULL;
/* drop conntrack reference */
nf_reset(skb);
spkt = (struct sockaddr_pkt*)skb->cb;
skb_push(skb, skb->data-skb->mac.raw);
/*
* The SOCK_PACKET socket receives _all_ frames.
*/
spkt->spkt_family = dev->type;
strlcpy(spkt->spkt_device, dev->name, sizeof(spkt->spkt_device));
spkt->spkt_protocol = skb->protocol;
/*
* Charge the memory to the socket. This is done specifically
* to prevent sockets using all the memory up.
*/
if (sock_queue_rcv_skb(sk,skb) == 0)
return 0;
out:
kfree_skb(skb);
oom:
return 0;
}
/*
* Output a raw packet to a device layer. This bypasses all the other
* protocol layers and you must therefore supply it with a complete frame
*/
static int packet_sendmsg_spkt(struct kiocb *iocb, struct socket *sock,
struct msghdr *msg, size_t len)
{
struct sock *sk = sock->sk;
struct sockaddr_pkt *saddr=(struct sockaddr_pkt *)msg->msg_name;
struct sk_buff *skb;
struct net_device *dev;
unsigned short proto=0;
int err;
/*
* Get and verify the address.
*/
if (saddr)
{
if (msg->msg_namelen < sizeof(struct sockaddr))
return(-EINVAL);
if (msg->msg_namelen==sizeof(struct sockaddr_pkt))
proto=saddr->spkt_protocol;
}
else
return(-ENOTCONN); /* SOCK_PACKET must be sent giving an address */
/*
* Find the device first to size check it
*/
saddr->spkt_device[13] = 0;
dev = dev_get_by_name(saddr->spkt_device);
err = -ENODEV;
if (dev == NULL)
goto out_unlock;
/*
* You may not queue a frame bigger than the mtu. This is the lowest level
* raw protocol and you must do your own fragmentation at this level.
*/
err = -EMSGSIZE;
if(len>dev->mtu+dev->hard_header_len)
goto out_unlock;
err = -ENOBUFS;
skb = sock_wmalloc(sk, len + LL_RESERVED_SPACE(dev), 0, GFP_KERNEL);
/*
* If the write buffer is full, then tough. At this level the user gets to
* deal with the problem - do your own algorithmic backoffs. That's far
* more flexible.
*/
if (skb == NULL)
goto out_unlock;
/*
* Fill it in
*/
/* FIXME: Save some space for broken drivers that write a
* hard header at transmission time by themselves. PPP is the
* notable one here. This should really be fixed at the driver level.
*/
skb_reserve(skb, LL_RESERVED_SPACE(dev));
skb->nh.raw = skb->data;
/* Try to align data part correctly */
if (dev->hard_header) {
skb->data -= dev->hard_header_len;
skb->tail -= dev->hard_header_len;
if (len < dev->hard_header_len)
skb->nh.raw = skb->data;
}
/* Returns -EFAULT on error */
err = memcpy_fromiovec(skb_put(skb,len), msg->msg_iov, len);
skb->protocol = proto;
skb->dev = dev;
skb->priority = sk->sk_priority;
if (err)
goto out_free;
err = -ENETDOWN;
if (!(dev->flags & IFF_UP))
goto out_free;
/*
* Now send it
*/
dev_queue_xmit(skb);
dev_put(dev);
return(len);
out_free:
kfree_skb(skb);
out_unlock:
if (dev)
dev_put(dev);
return err;
}
#endif
static inline unsigned run_filter(struct sk_buff *skb, struct sock *sk, unsigned res)
{
struct sk_filter *filter;
bh_lock_sock(sk);
filter = sk->sk_filter;
/*
* Our caller already checked that filter != NULL but we need to
* verify that under bh_lock_sock() to be safe
*/
if (likely(filter != NULL))
res = sk_run_filter(skb, filter->insns, filter->len);
bh_unlock_sock(sk);
return res;
}
/*
This function makes lazy skb cloning in hope that most of packets
are discarded by BPF.
Note tricky part: we DO mangle shared skb! skb->data, skb->len
and skb->cb are mangled. It works because (and until) packets
falling here are owned by current CPU. Output packets are cloned
by dev_queue_xmit_nit(), input packets are processed by net_bh
sequencially, so that if we return skb to original state on exit,
we will not harm anyone.
*/
static int packet_rcv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev)
{
struct sock *sk;
struct sockaddr_ll *sll;
struct packet_sock *po;
u8 * skb_head = skb->data;
int skb_len = skb->len;
unsigned snaplen;
if (skb->pkt_type == PACKET_LOOPBACK)
goto drop;
sk = pt->af_packet_priv;
po = pkt_sk(sk);
skb->dev = dev;
if (dev->hard_header) {
/* The device has an explicit notion of ll header,
exported to higher levels.
Otherwise, the device hides datails of it frame
structure, so that corresponding packet head
never delivered to user.
*/
if (sk->sk_type != SOCK_DGRAM)
skb_push(skb, skb->data - skb->mac.raw);
else if (skb->pkt_type == PACKET_OUTGOING) {
/* Special case: outgoing packets have ll header at head */
skb_pull(skb, skb->nh.raw - skb->data);
}
}
snaplen = skb->len;
if (sk->sk_filter) {
unsigned res = run_filter(skb, sk, snaplen);
if (res == 0)
goto drop_n_restore;
if (snaplen > res)
snaplen = res;
}
if (atomic_read(&sk->sk_rmem_alloc) + skb->truesize >=
(unsigned)sk->sk_rcvbuf)
goto drop_n_acct;
if (skb_shared(skb)) {
struct sk_buff *nskb = skb_clone(skb, GFP_ATOMIC);
if (nskb == NULL)
goto drop_n_acct;
if (skb_head != skb->data) {
skb->data = skb_head;
skb->len = skb_len;
}
kfree_skb(skb);
skb = nskb;
}
sll = (struct sockaddr_ll*)skb->cb;
sll->sll_family = AF_PACKET;
sll->sll_hatype = dev->type;
sll->sll_protocol = skb->protocol;
sll->sll_pkttype = skb->pkt_type;
sll->sll_ifindex = dev->ifindex;
sll->sll_halen = 0;
if (dev->hard_header_parse)
sll->sll_halen = dev->hard_header_parse(skb, sll->sll_addr);
if (pskb_trim(skb, snaplen))
goto drop_n_acct;
skb_set_owner_r(skb, sk);
skb->dev = NULL;
dst_release(skb->dst);
skb->dst = NULL;
/* drop conntrack reference */
nf_reset(skb);
spin_lock(&sk->sk_receive_queue.lock);
po->stats.tp_packets++;
__skb_queue_tail(&sk->sk_receive_queue, skb);
spin_unlock(&sk->sk_receive_queue.lock);
sk->sk_data_ready(sk, skb->len);
return 0;
drop_n_acct:
spin_lock(&sk->sk_receive_queue.lock);
po->stats.tp_drops++;
spin_unlock(&sk->sk_receive_queue.lock);
drop_n_restore:
if (skb_head != skb->data && skb_shared(skb)) {
skb->data = skb_head;
skb->len = skb_len;
}
drop:
kfree_skb(skb);
return 0;
}
#ifdef CONFIG_PACKET_MMAP
static int tpacket_rcv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev)
{
struct sock *sk;
struct packet_sock *po;
struct sockaddr_ll *sll;
struct tpacket_hdr *h;
u8 * skb_head = skb->data;
int skb_len = skb->len;
unsigned snaplen;
unsigned long status = TP_STATUS_LOSING|TP_STATUS_USER;
unsigned short macoff, netoff;
struct sk_buff *copy_skb = NULL;
if (skb->pkt_type == PACKET_LOOPBACK)
goto drop;
sk = pt->af_packet_priv;
po = pkt_sk(sk);
if (dev->hard_header) {
if (sk->sk_type != SOCK_DGRAM)
skb_push(skb, skb->data - skb->mac.raw);
else if (skb->pkt_type == PACKET_OUTGOING) {
/* Special case: outgoing packets have ll header at head */
skb_pull(skb, skb->nh.raw - skb->data);
if (skb->ip_summed == CHECKSUM_HW)
status |= TP_STATUS_CSUMNOTREADY;
}
}
snaplen = skb->len;
if (sk->sk_filter) {
unsigned res = run_filter(skb, sk, snaplen);
if (res == 0)
goto drop_n_restore;
if (snaplen > res)
snaplen = res;
}
if (sk->sk_type == SOCK_DGRAM) {
macoff = netoff = TPACKET_ALIGN(TPACKET_HDRLEN) + 16;
} else {
unsigned maclen = skb->nh.raw - skb->data;
netoff = TPACKET_ALIGN(TPACKET_HDRLEN + (maclen < 16 ? 16 : maclen));
macoff = netoff - maclen;
}
if (macoff + snaplen > po->frame_size) {
if (po->copy_thresh &&
atomic_read(&sk->sk_rmem_alloc) + skb->truesize <
(unsigned)sk->sk_rcvbuf) {
if (skb_shared(skb)) {
copy_skb = skb_clone(skb, GFP_ATOMIC);
} else {
copy_skb = skb_get(skb);
skb_head = skb->data;
}
if (copy_skb)
skb_set_owner_r(copy_skb, sk);
}
snaplen = po->frame_size - macoff;
if ((int)snaplen < 0)
snaplen = 0;
}
if (snaplen > skb->len-skb->data_len)
snaplen = skb->len-skb->data_len;
spin_lock(&sk->sk_receive_queue.lock);
h = (struct tpacket_hdr *)packet_lookup_frame(po, po->head);
if (h->tp_status)
goto ring_is_full;
po->head = po->head != po->frame_max ? po->head+1 : 0;
po->stats.tp_packets++;
if (copy_skb) {
status |= TP_STATUS_COPY;
__skb_queue_tail(&sk->sk_receive_queue, copy_skb);
}
if (!po->stats.tp_drops)
status &= ~TP_STATUS_LOSING;
spin_unlock(&sk->sk_receive_queue.lock);
memcpy((u8*)h + macoff, skb->data, snaplen);
h->tp_len = skb->len;
h->tp_snaplen = snaplen;
h->tp_mac = macoff;
h->tp_net = netoff;
if (skb->tstamp.off_sec == 0) {
__net_timestamp(skb);
sock_enable_timestamp(sk);
}
h->tp_sec = skb->tstamp.off_sec;
h->tp_usec = skb->tstamp.off_usec;
sll = (struct sockaddr_ll*)((u8*)h + TPACKET_ALIGN(sizeof(*h)));
sll->sll_halen = 0;
if (dev->hard_header_parse)
sll->sll_halen = dev->hard_header_parse(skb, sll->sll_addr);
sll->sll_family = AF_PACKET;
sll->sll_hatype = dev->type;
sll->sll_protocol = skb->protocol;
sll->sll_pkttype = skb->pkt_type;
sll->sll_ifindex = dev->ifindex;
h->tp_status = status;
mb();
{
struct page *p_start, *p_end;
u8 *h_end = (u8 *)h + macoff + snaplen - 1;
p_start = virt_to_page(h);
p_end = virt_to_page(h_end);
while (p_start <= p_end) {
flush_dcache_page(p_start);
p_start++;
}
}
sk->sk_data_ready(sk, 0);
drop_n_restore:
if (skb_head != skb->data && skb_shared(skb)) {
skb->data = skb_head;
skb->len = skb_len;
}
drop:
kfree_skb(skb);
return 0;
ring_is_full:
po->stats.tp_drops++;
spin_unlock(&sk->sk_receive_queue.lock);
sk->sk_data_ready(sk, 0);
if (copy_skb)
kfree_skb(copy_skb);
goto drop_n_restore;
}
#endif
static int packet_sendmsg(struct kiocb *iocb, struct socket *sock,
struct msghdr *msg, size_t len)
{
struct sock *sk = sock->sk;
struct sockaddr_ll *saddr=(struct sockaddr_ll *)msg->msg_name;
struct sk_buff *skb;
struct net_device *dev;
unsigned short proto;
unsigned char *addr;
int ifindex, err, reserve = 0;
/*
* Get and verify the address.
*/
if (saddr == NULL) {
struct packet_sock *po = pkt_sk(sk);
ifindex = po->ifindex;
proto = po->num;
addr = NULL;
} else {
err = -EINVAL;
if (msg->msg_namelen < sizeof(struct sockaddr_ll))
goto out;
if (msg->msg_namelen < (saddr->sll_halen + offsetof(struct sockaddr_ll, sll_addr)))
goto out;
ifindex = saddr->sll_ifindex;
proto = saddr->sll_protocol;
addr = saddr->sll_addr;
}
dev = dev_get_by_index(ifindex);
err = -ENXIO;
if (dev == NULL)
goto out_unlock;
if (sock->type == SOCK_RAW)
reserve = dev->hard_header_len;
err = -EMSGSIZE;
if (len > dev->mtu+reserve)
goto out_unlock;
skb = sock_alloc_send_skb(sk, len + LL_RESERVED_SPACE(dev),
msg->msg_flags & MSG_DONTWAIT, &err);
if (skb==NULL)
goto out_unlock;
skb_reserve(skb, LL_RESERVED_SPACE(dev));
skb->nh.raw = skb->data;
if (dev->hard_header) {
int res;
err = -EINVAL;
res = dev->hard_header(skb, dev, ntohs(proto), addr, NULL, len);
if (sock->type != SOCK_DGRAM) {
skb->tail = skb->data;
skb->len = 0;
} else if (res < 0)
goto out_free;
}
/* Returns -EFAULT on error */
err = memcpy_fromiovec(skb_put(skb,len), msg->msg_iov, len);
if (err)
goto out_free;
skb->protocol = proto;
skb->dev = dev;
skb->priority = sk->sk_priority;
err = -ENETDOWN;
if (!(dev->flags & IFF_UP))
goto out_free;
/*
* Now send it
*/
err = dev_queue_xmit(skb);
if (err > 0 && (err = net_xmit_errno(err)) != 0)
goto out_unlock;
dev_put(dev);
return(len);
out_free:
kfree_skb(skb);
out_unlock:
if (dev)
dev_put(dev);
out:
return err;
}
/*
* Close a PACKET socket. This is fairly simple. We immediately go
* to 'closed' state and remove our protocol entry in the device list.
*/
static int packet_release(struct socket *sock)
{
struct sock *sk = sock->sk;
struct packet_sock *po;
if (!sk)
return 0;
po = pkt_sk(sk);
write_lock_bh(&packet_sklist_lock);
sk_del_node_init(sk);
write_unlock_bh(&packet_sklist_lock);
/*
* Unhook packet receive handler.
*/
if (po->running) {
/*
* Remove the protocol hook
*/
dev_remove_pack(&po->prot_hook);
po->running = 0;
po->num = 0;
__sock_put(sk);
}
#ifdef CONFIG_PACKET_MULTICAST
packet_flush_mclist(sk);
#endif
#ifdef CONFIG_PACKET_MMAP
if (po->pg_vec) {
struct tpacket_req req;
memset(&req, 0, sizeof(req));
packet_set_ring(sk, &req, 1);
}
#endif
/*
* Now the socket is dead. No more input will appear.
*/
sock_orphan(sk);
sock->sk = NULL;
/* Purge queues */
skb_queue_purge(&sk->sk_receive_queue);
sock_put(sk);
return 0;
}
/*
* Attach a packet hook.
*/
static int packet_do_bind(struct sock *sk, struct net_device *dev, int protocol)
{
struct packet_sock *po = pkt_sk(sk);
/*
* Detach an existing hook if present.
*/
lock_sock(sk);
spin_lock(&po->bind_lock);
if (po->running) {
__sock_put(sk);
po->running = 0;
po->num = 0;
spin_unlock(&po->bind_lock);
dev_remove_pack(&po->prot_hook);
spin_lock(&po->bind_lock);
}
po->num = protocol;
po->prot_hook.type = protocol;
po->prot_hook.dev = dev;
po->ifindex = dev ? dev->ifindex : 0;
if (protocol == 0)
goto out_unlock;
if (dev) {
if (dev->flags&IFF_UP) {
dev_add_pack(&po->prot_hook);
sock_hold(sk);
po->running = 1;
} else {
sk->sk_err = ENETDOWN;
if (!sock_flag(sk, SOCK_DEAD))
sk->sk_error_report(sk);
}
} else {
dev_add_pack(&po->prot_hook);
sock_hold(sk);
po->running = 1;
}
out_unlock:
spin_unlock(&po->bind_lock);
release_sock(sk);
return 0;
}
/*
* Bind a packet socket to a device
*/
#ifdef CONFIG_SOCK_PACKET
static int packet_bind_spkt(struct socket *sock, struct sockaddr *uaddr, int addr_len)
{
struct sock *sk=sock->sk;
char name[15];
struct net_device *dev;
int err = -ENODEV;
/*
* Check legality
*/
if(addr_len!=sizeof(struct sockaddr))
return -EINVAL;
strlcpy(name,uaddr->sa_data,sizeof(name));
dev = dev_get_by_name(name);
if (dev) {
err = packet_do_bind(sk, dev, pkt_sk(sk)->num);
dev_put(dev);
}
return err;
}
#endif
static int packet_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
{
struct sockaddr_ll *sll = (struct sockaddr_ll*)uaddr;
struct sock *sk=sock->sk;
struct net_device *dev = NULL;
int err;
/*
* Check legality
*/
if (addr_len < sizeof(struct sockaddr_ll))
return -EINVAL;
if (sll->sll_family != AF_PACKET)
return -EINVAL;
if (sll->sll_ifindex) {
err = -ENODEV;
dev = dev_get_by_index(sll->sll_ifindex);
if (dev == NULL)
goto out;
}
err = packet_do_bind(sk, dev, sll->sll_protocol ? : pkt_sk(sk)->num);
if (dev)
dev_put(dev);
out:
return err;
}
static struct proto packet_proto = {
.name = "PACKET",
.owner = THIS_MODULE,
.obj_size = sizeof(struct packet_sock),
};
/*
* Create a packet of type SOCK_PACKET.
*/
static int packet_create(struct socket *sock, int protocol)
{
struct sock *sk;
struct packet_sock *po;
int err;
if (!capable(CAP_NET_RAW))
return -EPERM;
if (sock->type != SOCK_DGRAM && sock->type != SOCK_RAW