linux/net/socket.c
Alexey Dobriyan b87221de6a const: mark remaining super_operations const
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-09-22 07:17:24 -07:00

2455 lines
58 KiB
C

/*
* NET An implementation of the SOCKET network access protocol.
*
* Version: @(#)socket.c 1.1.93 18/02/95
*
* Authors: Orest Zborowski, <obz@Kodak.COM>
* Ross Biro
* Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
*
* Fixes:
* Anonymous : NOTSOCK/BADF cleanup. Error fix in
* shutdown()
* Alan Cox : verify_area() fixes
* Alan Cox : Removed DDI
* Jonathan Kamens : SOCK_DGRAM reconnect bug
* Alan Cox : Moved a load of checks to the very
* top level.
* Alan Cox : Move address structures to/from user
* mode above the protocol layers.
* Rob Janssen : Allow 0 length sends.
* Alan Cox : Asynchronous I/O support (cribbed from the
* tty drivers).
* Niibe Yutaka : Asynchronous I/O for writes (4.4BSD style)
* Jeff Uphoff : Made max number of sockets command-line
* configurable.
* Matti Aarnio : Made the number of sockets dynamic,
* to be allocated when needed, and mr.
* Uphoff's max is used as max to be
* allowed to allocate.
* Linus : Argh. removed all the socket allocation
* altogether: it's in the inode now.
* Alan Cox : Made sock_alloc()/sock_release() public
* for NetROM and future kernel nfsd type
* stuff.
* Alan Cox : sendmsg/recvmsg basics.
* Tom Dyas : Export net symbols.
* Marcin Dalecki : Fixed problems with CONFIG_NET="n".
* Alan Cox : Added thread locking to sys_* calls
* for sockets. May have errors at the
* moment.
* Kevin Buhr : Fixed the dumb errors in the above.
* Andi Kleen : Some small cleanups, optimizations,
* and fixed a copy_from_user() bug.
* Tigran Aivazian : sys_send(args) calls sys_sendto(args, NULL, 0)
* Tigran Aivazian : Made listen(2) backlog sanity checks
* protocol-independent
*
*
* 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.
*
*
* This module is effectively the top level interface to the BSD socket
* paradigm.
*
* Based upon Swansea University Computer Society NET3.039
*/
#include <linux/mm.h>
#include <linux/socket.h>
#include <linux/file.h>
#include <linux/net.h>
#include <linux/interrupt.h>
#include <linux/thread_info.h>
#include <linux/rcupdate.h>
#include <linux/netdevice.h>
#include <linux/proc_fs.h>
#include <linux/seq_file.h>
#include <linux/mutex.h>
#include <linux/wanrouter.h>
#include <linux/if_bridge.h>
#include <linux/if_frad.h>
#include <linux/if_vlan.h>
#include <linux/init.h>
#include <linux/poll.h>
#include <linux/cache.h>
#include <linux/module.h>
#include <linux/highmem.h>
#include <linux/mount.h>
#include <linux/security.h>
#include <linux/syscalls.h>
#include <linux/compat.h>
#include <linux/kmod.h>
#include <linux/audit.h>
#include <linux/wireless.h>
#include <linux/nsproxy.h>
#include <asm/uaccess.h>
#include <asm/unistd.h>
#include <net/compat.h>
#include <net/wext.h>
#include <net/sock.h>
#include <linux/netfilter.h>
static int sock_no_open(struct inode *irrelevant, struct file *dontcare);
static ssize_t sock_aio_read(struct kiocb *iocb, const struct iovec *iov,
unsigned long nr_segs, loff_t pos);
static ssize_t sock_aio_write(struct kiocb *iocb, const struct iovec *iov,
unsigned long nr_segs, loff_t pos);
static int sock_mmap(struct file *file, struct vm_area_struct *vma);
static int sock_close(struct inode *inode, struct file *file);
static unsigned int sock_poll(struct file *file,
struct poll_table_struct *wait);
static long sock_ioctl(struct file *file, unsigned int cmd, unsigned long arg);
#ifdef CONFIG_COMPAT
static long compat_sock_ioctl(struct file *file,
unsigned int cmd, unsigned long arg);
#endif
static int sock_fasync(int fd, struct file *filp, int on);
static ssize_t sock_sendpage(struct file *file, struct page *page,
int offset, size_t size, loff_t *ppos, int more);
static ssize_t sock_splice_read(struct file *file, loff_t *ppos,
struct pipe_inode_info *pipe, size_t len,
unsigned int flags);
/*
* Socket files have a set of 'special' operations as well as the generic file ones. These don't appear
* in the operation structures but are done directly via the socketcall() multiplexor.
*/
static const struct file_operations socket_file_ops = {
.owner = THIS_MODULE,
.llseek = no_llseek,
.aio_read = sock_aio_read,
.aio_write = sock_aio_write,
.poll = sock_poll,
.unlocked_ioctl = sock_ioctl,
#ifdef CONFIG_COMPAT
.compat_ioctl = compat_sock_ioctl,
#endif
.mmap = sock_mmap,
.open = sock_no_open, /* special open code to disallow open via /proc */
.release = sock_close,
.fasync = sock_fasync,
.sendpage = sock_sendpage,
.splice_write = generic_splice_sendpage,
.splice_read = sock_splice_read,
};
/*
* The protocol list. Each protocol is registered in here.
*/
static DEFINE_SPINLOCK(net_family_lock);
static const struct net_proto_family *net_families[NPROTO] __read_mostly;
/*
* Statistics counters of the socket lists
*/
static DEFINE_PER_CPU(int, sockets_in_use) = 0;
/*
* Support routines.
* Move socket addresses back and forth across the kernel/user
* divide and look after the messy bits.
*/
#define MAX_SOCK_ADDR 128 /* 108 for Unix domain -
16 for IP, 16 for IPX,
24 for IPv6,
about 80 for AX.25
must be at least one bigger than
the AF_UNIX size (see net/unix/af_unix.c
:unix_mkname()).
*/
/**
* move_addr_to_kernel - copy a socket address into kernel space
* @uaddr: Address in user space
* @kaddr: Address in kernel space
* @ulen: Length in user space
*
* The address is copied into kernel space. If the provided address is
* too long an error code of -EINVAL is returned. If the copy gives
* invalid addresses -EFAULT is returned. On a success 0 is returned.
*/
int move_addr_to_kernel(void __user *uaddr, int ulen, struct sockaddr *kaddr)
{
if (ulen < 0 || ulen > sizeof(struct sockaddr_storage))
return -EINVAL;
if (ulen == 0)
return 0;
if (copy_from_user(kaddr, uaddr, ulen))
return -EFAULT;
return audit_sockaddr(ulen, kaddr);
}
/**
* move_addr_to_user - copy an address to user space
* @kaddr: kernel space address
* @klen: length of address in kernel
* @uaddr: user space address
* @ulen: pointer to user length field
*
* The value pointed to by ulen on entry is the buffer length available.
* This is overwritten with the buffer space used. -EINVAL is returned
* if an overlong buffer is specified or a negative buffer size. -EFAULT
* is returned if either the buffer or the length field are not
* accessible.
* After copying the data up to the limit the user specifies, the true
* length of the data is written over the length limit the user
* specified. Zero is returned for a success.
*/
int move_addr_to_user(struct sockaddr *kaddr, int klen, void __user *uaddr,
int __user *ulen)
{
int err;
int len;
err = get_user(len, ulen);
if (err)
return err;
if (len > klen)
len = klen;
if (len < 0 || len > sizeof(struct sockaddr_storage))
return -EINVAL;
if (len) {
if (audit_sockaddr(klen, kaddr))
return -ENOMEM;
if (copy_to_user(uaddr, kaddr, len))
return -EFAULT;
}
/*
* "fromlen shall refer to the value before truncation.."
* 1003.1g
*/
return __put_user(klen, ulen);
}
#define SOCKFS_MAGIC 0x534F434B
static struct kmem_cache *sock_inode_cachep __read_mostly;
static struct inode *sock_alloc_inode(struct super_block *sb)
{
struct socket_alloc *ei;
ei = kmem_cache_alloc(sock_inode_cachep, GFP_KERNEL);
if (!ei)
return NULL;
init_waitqueue_head(&ei->socket.wait);
ei->socket.fasync_list = NULL;
ei->socket.state = SS_UNCONNECTED;
ei->socket.flags = 0;
ei->socket.ops = NULL;
ei->socket.sk = NULL;
ei->socket.file = NULL;
return &ei->vfs_inode;
}
static void sock_destroy_inode(struct inode *inode)
{
kmem_cache_free(sock_inode_cachep,
container_of(inode, struct socket_alloc, vfs_inode));
}
static void init_once(void *foo)
{
struct socket_alloc *ei = (struct socket_alloc *)foo;
inode_init_once(&ei->vfs_inode);
}
static int init_inodecache(void)
{
sock_inode_cachep = kmem_cache_create("sock_inode_cache",
sizeof(struct socket_alloc),
0,
(SLAB_HWCACHE_ALIGN |
SLAB_RECLAIM_ACCOUNT |
SLAB_MEM_SPREAD),
init_once);
if (sock_inode_cachep == NULL)
return -ENOMEM;
return 0;
}
static const struct super_operations sockfs_ops = {
.alloc_inode = sock_alloc_inode,
.destroy_inode =sock_destroy_inode,
.statfs = simple_statfs,
};
static int sockfs_get_sb(struct file_system_type *fs_type,
int flags, const char *dev_name, void *data,
struct vfsmount *mnt)
{
return get_sb_pseudo(fs_type, "socket:", &sockfs_ops, SOCKFS_MAGIC,
mnt);
}
static struct vfsmount *sock_mnt __read_mostly;
static struct file_system_type sock_fs_type = {
.name = "sockfs",
.get_sb = sockfs_get_sb,
.kill_sb = kill_anon_super,
};
static int sockfs_delete_dentry(struct dentry *dentry)
{
/*
* At creation time, we pretended this dentry was hashed
* (by clearing DCACHE_UNHASHED bit in d_flags)
* At delete time, we restore the truth : not hashed.
* (so that dput() can proceed correctly)
*/
dentry->d_flags |= DCACHE_UNHASHED;
return 0;
}
/*
* sockfs_dname() is called from d_path().
*/
static char *sockfs_dname(struct dentry *dentry, char *buffer, int buflen)
{
return dynamic_dname(dentry, buffer, buflen, "socket:[%lu]",
dentry->d_inode->i_ino);
}
static const struct dentry_operations sockfs_dentry_operations = {
.d_delete = sockfs_delete_dentry,
.d_dname = sockfs_dname,
};
/*
* Obtains the first available file descriptor and sets it up for use.
*
* These functions create file structures and maps them to fd space
* of the current process. On success it returns file descriptor
* and file struct implicitly stored in sock->file.
* Note that another thread may close file descriptor before we return
* from this function. We use the fact that now we do not refer
* to socket after mapping. If one day we will need it, this
* function will increment ref. count on file by 1.
*
* In any case returned fd MAY BE not valid!
* This race condition is unavoidable
* with shared fd spaces, we cannot solve it inside kernel,
* but we take care of internal coherence yet.
*/
static int sock_alloc_fd(struct file **filep, int flags)
{
int fd;
fd = get_unused_fd_flags(flags);
if (likely(fd >= 0)) {
struct file *file = get_empty_filp();
*filep = file;
if (unlikely(!file)) {
put_unused_fd(fd);
return -ENFILE;
}
} else
*filep = NULL;
return fd;
}
static int sock_attach_fd(struct socket *sock, struct file *file, int flags)
{
struct dentry *dentry;
struct qstr name = { .name = "" };
dentry = d_alloc(sock_mnt->mnt_sb->s_root, &name);
if (unlikely(!dentry))
return -ENOMEM;
dentry->d_op = &sockfs_dentry_operations;
/*
* We dont want to push this dentry into global dentry hash table.
* We pretend dentry is already hashed, by unsetting DCACHE_UNHASHED
* This permits a working /proc/$pid/fd/XXX on sockets
*/
dentry->d_flags &= ~DCACHE_UNHASHED;
d_instantiate(dentry, SOCK_INODE(sock));
sock->file = file;
init_file(file, sock_mnt, dentry, FMODE_READ | FMODE_WRITE,
&socket_file_ops);
SOCK_INODE(sock)->i_fop = &socket_file_ops;
file->f_flags = O_RDWR | (flags & O_NONBLOCK);
file->f_pos = 0;
file->private_data = sock;
return 0;
}
int sock_map_fd(struct socket *sock, int flags)
{
struct file *newfile;
int fd = sock_alloc_fd(&newfile, flags);
if (likely(fd >= 0)) {
int err = sock_attach_fd(sock, newfile, flags);
if (unlikely(err < 0)) {
put_filp(newfile);
put_unused_fd(fd);
return err;
}
fd_install(fd, newfile);
}
return fd;
}
static struct socket *sock_from_file(struct file *file, int *err)
{
if (file->f_op == &socket_file_ops)
return file->private_data; /* set in sock_map_fd */
*err = -ENOTSOCK;
return NULL;
}
/**
* sockfd_lookup - Go from a file number to its socket slot
* @fd: file handle
* @err: pointer to an error code return
*
* The file handle passed in is locked and the socket it is bound
* too is returned. If an error occurs the err pointer is overwritten
* with a negative errno code and NULL is returned. The function checks
* for both invalid handles and passing a handle which is not a socket.
*
* On a success the socket object pointer is returned.
*/
struct socket *sockfd_lookup(int fd, int *err)
{
struct file *file;
struct socket *sock;
file = fget(fd);
if (!file) {
*err = -EBADF;
return NULL;
}
sock = sock_from_file(file, err);
if (!sock)
fput(file);
return sock;
}
static struct socket *sockfd_lookup_light(int fd, int *err, int *fput_needed)
{
struct file *file;
struct socket *sock;
*err = -EBADF;
file = fget_light(fd, fput_needed);
if (file) {
sock = sock_from_file(file, err);
if (sock)
return sock;
fput_light(file, *fput_needed);
}
return NULL;
}
/**
* sock_alloc - allocate a socket
*
* Allocate a new inode and socket object. The two are bound together
* and initialised. The socket is then returned. If we are out of inodes
* NULL is returned.
*/
static struct socket *sock_alloc(void)
{
struct inode *inode;
struct socket *sock;
inode = new_inode(sock_mnt->mnt_sb);
if (!inode)
return NULL;
sock = SOCKET_I(inode);
kmemcheck_annotate_bitfield(sock, type);
inode->i_mode = S_IFSOCK | S_IRWXUGO;
inode->i_uid = current_fsuid();
inode->i_gid = current_fsgid();
percpu_add(sockets_in_use, 1);
return sock;
}
/*
* In theory you can't get an open on this inode, but /proc provides
* a back door. Remember to keep it shut otherwise you'll let the
* creepy crawlies in.
*/
static int sock_no_open(struct inode *irrelevant, struct file *dontcare)
{
return -ENXIO;
}
const struct file_operations bad_sock_fops = {
.owner = THIS_MODULE,
.open = sock_no_open,
};
/**
* sock_release - close a socket
* @sock: socket to close
*
* The socket is released from the protocol stack if it has a release
* callback, and the inode is then released if the socket is bound to
* an inode not a file.
*/
void sock_release(struct socket *sock)
{
if (sock->ops) {
struct module *owner = sock->ops->owner;
sock->ops->release(sock);
sock->ops = NULL;
module_put(owner);
}
if (sock->fasync_list)
printk(KERN_ERR "sock_release: fasync list not empty!\n");
percpu_sub(sockets_in_use, 1);
if (!sock->file) {
iput(SOCK_INODE(sock));
return;
}
sock->file = NULL;
}
int sock_tx_timestamp(struct msghdr *msg, struct sock *sk,
union skb_shared_tx *shtx)
{
shtx->flags = 0;
if (sock_flag(sk, SOCK_TIMESTAMPING_TX_HARDWARE))
shtx->hardware = 1;
if (sock_flag(sk, SOCK_TIMESTAMPING_TX_SOFTWARE))
shtx->software = 1;
return 0;
}
EXPORT_SYMBOL(sock_tx_timestamp);
static inline int __sock_sendmsg(struct kiocb *iocb, struct socket *sock,
struct msghdr *msg, size_t size)
{
struct sock_iocb *si = kiocb_to_siocb(iocb);
int err;
si->sock = sock;
si->scm = NULL;
si->msg = msg;
si->size = size;
err = security_socket_sendmsg(sock, msg, size);
if (err)
return err;
return sock->ops->sendmsg(iocb, sock, msg, size);
}
int sock_sendmsg(struct socket *sock, struct msghdr *msg, size_t size)
{
struct kiocb iocb;
struct sock_iocb siocb;
int ret;
init_sync_kiocb(&iocb, NULL);
iocb.private = &siocb;
ret = __sock_sendmsg(&iocb, sock, msg, size);
if (-EIOCBQUEUED == ret)
ret = wait_on_sync_kiocb(&iocb);
return ret;
}
int kernel_sendmsg(struct socket *sock, struct msghdr *msg,
struct kvec *vec, size_t num, size_t size)
{
mm_segment_t oldfs = get_fs();
int result;
set_fs(KERNEL_DS);
/*
* the following is safe, since for compiler definitions of kvec and
* iovec are identical, yielding the same in-core layout and alignment
*/
msg->msg_iov = (struct iovec *)vec;
msg->msg_iovlen = num;
result = sock_sendmsg(sock, msg, size);
set_fs(oldfs);
return result;
}
static int ktime2ts(ktime_t kt, struct timespec *ts)
{
if (kt.tv64) {
*ts = ktime_to_timespec(kt);
return 1;
} else {
return 0;
}
}
/*
* called from sock_recv_timestamp() if sock_flag(sk, SOCK_RCVTSTAMP)
*/
void __sock_recv_timestamp(struct msghdr *msg, struct sock *sk,
struct sk_buff *skb)
{
int need_software_tstamp = sock_flag(sk, SOCK_RCVTSTAMP);
struct timespec ts[3];
int empty = 1;
struct skb_shared_hwtstamps *shhwtstamps =
skb_hwtstamps(skb);
/* Race occurred between timestamp enabling and packet
receiving. Fill in the current time for now. */
if (need_software_tstamp && skb->tstamp.tv64 == 0)
__net_timestamp(skb);
if (need_software_tstamp) {
if (!sock_flag(sk, SOCK_RCVTSTAMPNS)) {
struct timeval tv;
skb_get_timestamp(skb, &tv);
put_cmsg(msg, SOL_SOCKET, SCM_TIMESTAMP,
sizeof(tv), &tv);
} else {
struct timespec ts;
skb_get_timestampns(skb, &ts);
put_cmsg(msg, SOL_SOCKET, SCM_TIMESTAMPNS,
sizeof(ts), &ts);
}
}
memset(ts, 0, sizeof(ts));
if (skb->tstamp.tv64 &&
sock_flag(sk, SOCK_TIMESTAMPING_SOFTWARE)) {
skb_get_timestampns(skb, ts + 0);
empty = 0;
}
if (shhwtstamps) {
if (sock_flag(sk, SOCK_TIMESTAMPING_SYS_HARDWARE) &&
ktime2ts(shhwtstamps->syststamp, ts + 1))
empty = 0;
if (sock_flag(sk, SOCK_TIMESTAMPING_RAW_HARDWARE) &&
ktime2ts(shhwtstamps->hwtstamp, ts + 2))
empty = 0;
}
if (!empty)
put_cmsg(msg, SOL_SOCKET,
SCM_TIMESTAMPING, sizeof(ts), &ts);
}
EXPORT_SYMBOL_GPL(__sock_recv_timestamp);
static inline int __sock_recvmsg(struct kiocb *iocb, struct socket *sock,
struct msghdr *msg, size_t size, int flags)
{
int err;
struct sock_iocb *si = kiocb_to_siocb(iocb);
si->sock = sock;
si->scm = NULL;
si->msg = msg;
si->size = size;
si->flags = flags;
err = security_socket_recvmsg(sock, msg, size, flags);
if (err)
return err;
return sock->ops->recvmsg(iocb, sock, msg, size, flags);
}
int sock_recvmsg(struct socket *sock, struct msghdr *msg,
size_t size, int flags)
{
struct kiocb iocb;
struct sock_iocb siocb;
int ret;
init_sync_kiocb(&iocb, NULL);
iocb.private = &siocb;
ret = __sock_recvmsg(&iocb, sock, msg, size, flags);
if (-EIOCBQUEUED == ret)
ret = wait_on_sync_kiocb(&iocb);
return ret;
}
int kernel_recvmsg(struct socket *sock, struct msghdr *msg,
struct kvec *vec, size_t num, size_t size, int flags)
{
mm_segment_t oldfs = get_fs();
int result;
set_fs(KERNEL_DS);
/*
* the following is safe, since for compiler definitions of kvec and
* iovec are identical, yielding the same in-core layout and alignment
*/
msg->msg_iov = (struct iovec *)vec, msg->msg_iovlen = num;
result = sock_recvmsg(sock, msg, size, flags);
set_fs(oldfs);
return result;
}
static void sock_aio_dtor(struct kiocb *iocb)
{
kfree(iocb->private);
}
static ssize_t sock_sendpage(struct file *file, struct page *page,
int offset, size_t size, loff_t *ppos, int more)
{
struct socket *sock;
int flags;
sock = file->private_data;
flags = !(file->f_flags & O_NONBLOCK) ? 0 : MSG_DONTWAIT;
if (more)
flags |= MSG_MORE;
return kernel_sendpage(sock, page, offset, size, flags);
}
static ssize_t sock_splice_read(struct file *file, loff_t *ppos,
struct pipe_inode_info *pipe, size_t len,
unsigned int flags)
{
struct socket *sock = file->private_data;
if (unlikely(!sock->ops->splice_read))
return -EINVAL;
return sock->ops->splice_read(sock, ppos, pipe, len, flags);
}
static struct sock_iocb *alloc_sock_iocb(struct kiocb *iocb,
struct sock_iocb *siocb)
{
if (!is_sync_kiocb(iocb)) {
siocb = kmalloc(sizeof(*siocb), GFP_KERNEL);
if (!siocb)
return NULL;
iocb->ki_dtor = sock_aio_dtor;
}
siocb->kiocb = iocb;
iocb->private = siocb;
return siocb;
}
static ssize_t do_sock_read(struct msghdr *msg, struct kiocb *iocb,
struct file *file, const struct iovec *iov,
unsigned long nr_segs)
{
struct socket *sock = file->private_data;
size_t size = 0;
int i;
for (i = 0; i < nr_segs; i++)
size += iov[i].iov_len;
msg->msg_name = NULL;
msg->msg_namelen = 0;
msg->msg_control = NULL;
msg->msg_controllen = 0;
msg->msg_iov = (struct iovec *)iov;
msg->msg_iovlen = nr_segs;
msg->msg_flags = (file->f_flags & O_NONBLOCK) ? MSG_DONTWAIT : 0;
return __sock_recvmsg(iocb, sock, msg, size, msg->msg_flags);
}
static ssize_t sock_aio_read(struct kiocb *iocb, const struct iovec *iov,
unsigned long nr_segs, loff_t pos)
{
struct sock_iocb siocb, *x;
if (pos != 0)
return -ESPIPE;
if (iocb->ki_left == 0) /* Match SYS5 behaviour */
return 0;
x = alloc_sock_iocb(iocb, &siocb);
if (!x)
return -ENOMEM;
return do_sock_read(&x->async_msg, iocb, iocb->ki_filp, iov, nr_segs);
}
static ssize_t do_sock_write(struct msghdr *msg, struct kiocb *iocb,
struct file *file, const struct iovec *iov,
unsigned long nr_segs)
{
struct socket *sock = file->private_data;
size_t size = 0;
int i;
for (i = 0; i < nr_segs; i++)
size += iov[i].iov_len;
msg->msg_name = NULL;
msg->msg_namelen = 0;
msg->msg_control = NULL;
msg->msg_controllen = 0;
msg->msg_iov = (struct iovec *)iov;
msg->msg_iovlen = nr_segs;
msg->msg_flags = (file->f_flags & O_NONBLOCK) ? MSG_DONTWAIT : 0;
if (sock->type == SOCK_SEQPACKET)
msg->msg_flags |= MSG_EOR;
return __sock_sendmsg(iocb, sock, msg, size);
}
static ssize_t sock_aio_write(struct kiocb *iocb, const struct iovec *iov,
unsigned long nr_segs, loff_t pos)
{
struct sock_iocb siocb, *x;
if (pos != 0)
return -ESPIPE;
x = alloc_sock_iocb(iocb, &siocb);
if (!x)
return -ENOMEM;
return do_sock_write(&x->async_msg, iocb, iocb->ki_filp, iov, nr_segs);
}
/*
* Atomic setting of ioctl hooks to avoid race
* with module unload.
*/
static DEFINE_MUTEX(br_ioctl_mutex);
static int (*br_ioctl_hook) (struct net *, unsigned int cmd, void __user *arg) = NULL;
void brioctl_set(int (*hook) (struct net *, unsigned int, void __user *))
{
mutex_lock(&br_ioctl_mutex);
br_ioctl_hook = hook;
mutex_unlock(&br_ioctl_mutex);
}
EXPORT_SYMBOL(brioctl_set);
static DEFINE_MUTEX(vlan_ioctl_mutex);
static int (*vlan_ioctl_hook) (struct net *, void __user *arg);
void vlan_ioctl_set(int (*hook) (struct net *, void __user *))
{
mutex_lock(&vlan_ioctl_mutex);
vlan_ioctl_hook = hook;
mutex_unlock(&vlan_ioctl_mutex);
}
EXPORT_SYMBOL(vlan_ioctl_set);
static DEFINE_MUTEX(dlci_ioctl_mutex);
static int (*dlci_ioctl_hook) (unsigned int, void __user *);
void dlci_ioctl_set(int (*hook) (unsigned int, void __user *))
{
mutex_lock(&dlci_ioctl_mutex);
dlci_ioctl_hook = hook;
mutex_unlock(&dlci_ioctl_mutex);
}
EXPORT_SYMBOL(dlci_ioctl_set);
/*
* With an ioctl, arg may well be a user mode pointer, but we don't know
* what to do with it - that's up to the protocol still.
*/
static long sock_ioctl(struct file *file, unsigned cmd, unsigned long arg)
{
struct socket *sock;
struct sock *sk;
void __user *argp = (void __user *)arg;
int pid, err;
struct net *net;
sock = file->private_data;
sk = sock->sk;
net = sock_net(sk);
if (cmd >= SIOCDEVPRIVATE && cmd <= (SIOCDEVPRIVATE + 15)) {
err = dev_ioctl(net, cmd, argp);
} else
#ifdef CONFIG_WIRELESS_EXT
if (cmd >= SIOCIWFIRST && cmd <= SIOCIWLAST) {
err = dev_ioctl(net, cmd, argp);
} else
#endif /* CONFIG_WIRELESS_EXT */
switch (cmd) {
case FIOSETOWN:
case SIOCSPGRP:
err = -EFAULT;
if (get_user(pid, (int __user *)argp))
break;
err = f_setown(sock->file, pid, 1);
break;
case FIOGETOWN:
case SIOCGPGRP:
err = put_user(f_getown(sock->file),
(int __user *)argp);
break;
case SIOCGIFBR:
case SIOCSIFBR:
case SIOCBRADDBR:
case SIOCBRDELBR:
err = -ENOPKG;
if (!br_ioctl_hook)
request_module("bridge");
mutex_lock(&br_ioctl_mutex);
if (br_ioctl_hook)
err = br_ioctl_hook(net, cmd, argp);
mutex_unlock(&br_ioctl_mutex);
break;
case SIOCGIFVLAN:
case SIOCSIFVLAN:
err = -ENOPKG;
if (!vlan_ioctl_hook)
request_module("8021q");
mutex_lock(&vlan_ioctl_mutex);
if (vlan_ioctl_hook)
err = vlan_ioctl_hook(net, argp);
mutex_unlock(&vlan_ioctl_mutex);
break;
case SIOCADDDLCI:
case SIOCDELDLCI:
err = -ENOPKG;
if (!dlci_ioctl_hook)
request_module("dlci");
mutex_lock(&dlci_ioctl_mutex);
if (dlci_ioctl_hook)
err = dlci_ioctl_hook(cmd, argp);
mutex_unlock(&dlci_ioctl_mutex);
break;
default:
err = sock->ops->ioctl(sock, cmd, arg);
/*
* If this ioctl is unknown try to hand it down
* to the NIC driver.
*/
if (err == -ENOIOCTLCMD)
err = dev_ioctl(net, cmd, argp);
break;
}
return err;
}
int sock_create_lite(int family, int type, int protocol, struct socket **res)
{
int err;
struct socket *sock = NULL;
err = security_socket_create(family, type, protocol, 1);
if (err)
goto out;
sock = sock_alloc();
if (!sock) {
err = -ENOMEM;
goto out;
}
sock->type = type;
err = security_socket_post_create(sock, family, type, protocol, 1);
if (err)
goto out_release;
out:
*res = sock;
return err;
out_release:
sock_release(sock);
sock = NULL;
goto out;
}
/* No kernel lock held - perfect */
static unsigned int sock_poll(struct file *file, poll_table *wait)
{
struct socket *sock;
/*
* We can't return errors to poll, so it's either yes or no.
*/
sock = file->private_data;
return sock->ops->poll(file, sock, wait);
}
static int sock_mmap(struct file *file, struct vm_area_struct *vma)
{
struct socket *sock = file->private_data;
return sock->ops->mmap(file, sock, vma);
}
static int sock_close(struct inode *inode, struct file *filp)
{
/*
* It was possible the inode is NULL we were
* closing an unfinished socket.
*/
if (!inode) {
printk(KERN_DEBUG "sock_close: NULL inode\n");
return 0;
}
sock_release(SOCKET_I(inode));
return 0;
}
/*
* Update the socket async list
*
* Fasync_list locking strategy.
*
* 1. fasync_list is modified only under process context socket lock
* i.e. under semaphore.
* 2. fasync_list is used under read_lock(&sk->sk_callback_lock)
* or under socket lock.
* 3. fasync_list can be used from softirq context, so that
* modification under socket lock have to be enhanced with
* write_lock_bh(&sk->sk_callback_lock).
* --ANK (990710)
*/
static int sock_fasync(int fd, struct file *filp, int on)
{
struct fasync_struct *fa, *fna = NULL, **prev;
struct socket *sock;
struct sock *sk;
if (on) {
fna = kmalloc(sizeof(struct fasync_struct), GFP_KERNEL);
if (fna == NULL)
return -ENOMEM;
}
sock = filp->private_data;
sk = sock->sk;
if (sk == NULL) {
kfree(fna);
return -EINVAL;
}
lock_sock(sk);
spin_lock(&filp->f_lock);
if (on)
filp->f_flags |= FASYNC;
else
filp->f_flags &= ~FASYNC;
spin_unlock(&filp->f_lock);
prev = &(sock->fasync_list);
for (fa = *prev; fa != NULL; prev = &fa->fa_next, fa = *prev)
if (fa->fa_file == filp)
break;
if (on) {
if (fa != NULL) {
write_lock_bh(&sk->sk_callback_lock);
fa->fa_fd = fd;
write_unlock_bh(&sk->sk_callback_lock);
kfree(fna);
goto out;
}
fna->fa_file = filp;
fna->fa_fd = fd;
fna->magic = FASYNC_MAGIC;
fna->fa_next = sock->fasync_list;
write_lock_bh(&sk->sk_callback_lock);
sock->fasync_list = fna;
write_unlock_bh(&sk->sk_callback_lock);
} else {
if (fa != NULL) {
write_lock_bh(&sk->sk_callback_lock);
*prev = fa->fa_next;
write_unlock_bh(&sk->sk_callback_lock);
kfree(fa);
}
}
out:
release_sock(sock->sk);
return 0;
}
/* This function may be called only under socket lock or callback_lock */
int sock_wake_async(struct socket *sock, int how, int band)
{
if (!sock || !sock->fasync_list)
return -1;
switch (how) {
case SOCK_WAKE_WAITD:
if (test_bit(SOCK_ASYNC_WAITDATA, &sock->flags))
break;
goto call_kill;
case SOCK_WAKE_SPACE:
if (!test_and_clear_bit(SOCK_ASYNC_NOSPACE, &sock->flags))
break;
/* fall through */
case SOCK_WAKE_IO:
call_kill:
__kill_fasync(sock->fasync_list, SIGIO, band);
break;
case SOCK_WAKE_URG:
__kill_fasync(sock->fasync_list, SIGURG, band);
}
return 0;
}
static int __sock_create(struct net *net, int family, int type, int protocol,
struct socket **res, int kern)
{
int err;
struct socket *sock;
const struct net_proto_family *pf;
/*
* Check protocol is in range
*/
if (family < 0 || family >= NPROTO)
return -EAFNOSUPPORT;
if (type < 0 || type >= SOCK_MAX)
return -EINVAL;
/* Compatibility.
This uglymoron is moved from INET layer to here to avoid
deadlock in module load.
*/
if (family == PF_INET && type == SOCK_PACKET) {
static int warned;
if (!warned) {
warned = 1;
printk(KERN_INFO "%s uses obsolete (PF_INET,SOCK_PACKET)\n",
current->comm);
}
family = PF_PACKET;
}
err = security_socket_create(family, type, protocol, kern);
if (err)
return err;
/*
* Allocate the socket and allow the family to set things up. if
* the protocol is 0, the family is instructed to select an appropriate
* default.
*/
sock = sock_alloc();
if (!sock) {
if (net_ratelimit())
printk(KERN_WARNING "socket: no more sockets\n");
return -ENFILE; /* Not exactly a match, but its the
closest posix thing */
}
sock->type = type;
#ifdef CONFIG_MODULES
/* Attempt to load a protocol module if the find failed.
*
* 12/09/1996 Marcin: But! this makes REALLY only sense, if the user
* requested real, full-featured networking support upon configuration.
* Otherwise module support will break!
*/
if (net_families[family] == NULL)
request_module("net-pf-%d", family);
#endif
rcu_read_lock();
pf = rcu_dereference(net_families[family]);
err = -EAFNOSUPPORT;
if (!pf)
goto out_release;
/*
* We will call the ->create function, that possibly is in a loadable
* module, so we have to bump that loadable module refcnt first.
*/
if (!try_module_get(pf->owner))
goto out_release;
/* Now protected by module ref count */
rcu_read_unlock();
err = pf->create(net, sock, protocol);
if (err < 0)
goto out_module_put;
/*
* Now to bump the refcnt of the [loadable] module that owns this
* socket at sock_release time we decrement its refcnt.
*/
if (!try_module_get(sock->ops->owner))
goto out_module_busy;
/*
* Now that we're done with the ->create function, the [loadable]
* module can have its refcnt decremented
*/
module_put(pf->owner);
err = security_socket_post_create(sock, family, type, protocol, kern);
if (err)
goto out_sock_release;
*res = sock;
return 0;
out_module_busy:
err = -EAFNOSUPPORT;
out_module_put:
sock->ops = NULL;
module_put(pf->owner);
out_sock_release:
sock_release(sock);
return err;
out_release:
rcu_read_unlock();
goto out_sock_release;
}
int sock_create(int family, int type, int protocol, struct socket **res)
{
return __sock_create(current->nsproxy->net_ns, family, type, protocol, res, 0);
}
int sock_create_kern(int family, int type, int protocol, struct socket **res)
{
return __sock_create(&init_net, family, type, protocol, res, 1);
}
SYSCALL_DEFINE3(socket, int, family, int, type, int, protocol)
{
int retval;
struct socket *sock;
int flags;
/* Check the SOCK_* constants for consistency. */
BUILD_BUG_ON(SOCK_CLOEXEC != O_CLOEXEC);
BUILD_BUG_ON((SOCK_MAX | SOCK_TYPE_MASK) != SOCK_TYPE_MASK);
BUILD_BUG_ON(SOCK_CLOEXEC & SOCK_TYPE_MASK);
BUILD_BUG_ON(SOCK_NONBLOCK & SOCK_TYPE_MASK);
flags = type & ~SOCK_TYPE_MASK;
if (flags & ~(SOCK_CLOEXEC | SOCK_NONBLOCK))
return -EINVAL;
type &= SOCK_TYPE_MASK;
if (SOCK_NONBLOCK != O_NONBLOCK && (flags & SOCK_NONBLOCK))
flags = (flags & ~SOCK_NONBLOCK) | O_NONBLOCK;
retval = sock_create(family, type, protocol, &sock);
if (retval < 0)
goto out;
retval = sock_map_fd(sock, flags & (O_CLOEXEC | O_NONBLOCK));
if (retval < 0)
goto out_release;
out:
/* It may be already another descriptor 8) Not kernel problem. */
return retval;
out_release:
sock_release(sock);
return retval;
}
/*
* Create a pair of connected sockets.
*/
SYSCALL_DEFINE4(socketpair, int, family, int, type, int, protocol,
int __user *, usockvec)
{
struct socket *sock1, *sock2;
int fd1, fd2, err;
struct file *newfile1, *newfile2;
int flags;
flags = type & ~SOCK_TYPE_MASK;
if (flags & ~(SOCK_CLOEXEC | SOCK_NONBLOCK))
return -EINVAL;
type &= SOCK_TYPE_MASK;
if (SOCK_NONBLOCK != O_NONBLOCK && (flags & SOCK_NONBLOCK))
flags = (flags & ~SOCK_NONBLOCK) | O_NONBLOCK;
/*
* Obtain the first socket and check if the underlying protocol
* supports the socketpair call.
*/
err = sock_create(family, type, protocol, &sock1);
if (err < 0)
goto out;
err = sock_create(family, type, protocol, &sock2);
if (err < 0)
goto out_release_1;
err = sock1->ops->socketpair(sock1, sock2);
if (err < 0)
goto out_release_both;
fd1 = sock_alloc_fd(&newfile1, flags & O_CLOEXEC);
if (unlikely(fd1 < 0)) {
err = fd1;
goto out_release_both;
}
fd2 = sock_alloc_fd(&newfile2, flags & O_CLOEXEC);
if (unlikely(fd2 < 0)) {
err = fd2;
put_filp(newfile1);
put_unused_fd(fd1);
goto out_release_both;
}
err = sock_attach_fd(sock1, newfile1, flags & O_NONBLOCK);
if (unlikely(err < 0)) {
goto out_fd2;
}
err = sock_attach_fd(sock2, newfile2, flags & O_NONBLOCK);
if (unlikely(err < 0)) {
fput(newfile1);
goto out_fd1;
}
audit_fd_pair(fd1, fd2);
fd_install(fd1, newfile1);
fd_install(fd2, newfile2);
/* fd1 and fd2 may be already another descriptors.
* Not kernel problem.
*/
err = put_user(fd1, &usockvec[0]);
if (!err)
err = put_user(fd2, &usockvec[1]);
if (!err)
return 0;
sys_close(fd2);
sys_close(fd1);
return err;
out_release_both:
sock_release(sock2);
out_release_1:
sock_release(sock1);
out:
return err;
out_fd2:
put_filp(newfile1);
sock_release(sock1);
out_fd1:
put_filp(newfile2);
sock_release(sock2);
put_unused_fd(fd1);
put_unused_fd(fd2);
goto out;
}
/*
* Bind a name to a socket. Nothing much to do here since it's
* the protocol's responsibility to handle the local address.
*
* We move the socket address to kernel space before we call
* the protocol layer (having also checked the address is ok).
*/
SYSCALL_DEFINE3(bind, int, fd, struct sockaddr __user *, umyaddr, int, addrlen)
{
struct socket *sock;
struct sockaddr_storage address;
int err, fput_needed;
sock = sockfd_lookup_light(fd, &err, &fput_needed);
if (sock) {
err = move_addr_to_kernel(umyaddr, addrlen, (struct sockaddr *)&address);
if (err >= 0) {
err = security_socket_bind(sock,
(struct sockaddr *)&address,
addrlen);
if (!err)
err = sock->ops->bind(sock,
(struct sockaddr *)
&address, addrlen);
}
fput_light(sock->file, fput_needed);
}
return err;
}
/*
* Perform a listen. Basically, we allow the protocol to do anything
* necessary for a listen, and if that works, we mark the socket as
* ready for listening.
*/
SYSCALL_DEFINE2(listen, int, fd, int, backlog)
{
struct socket *sock;
int err, fput_needed;
int somaxconn;
sock = sockfd_lookup_light(fd, &err, &fput_needed);
if (sock) {
somaxconn = sock_net(sock->sk)->core.sysctl_somaxconn;
if ((unsigned)backlog > somaxconn)
backlog = somaxconn;
err = security_socket_listen(sock, backlog);
if (!err)
err = sock->ops->listen(sock, backlog);
fput_light(sock->file, fput_needed);
}
return err;
}
/*
* For accept, we attempt to create a new socket, set up the link
* with the client, wake up the client, then return the new
* connected fd. We collect the address of the connector in kernel
* space and move it to user at the very end. This is unclean because
* we open the socket then return an error.
*
* 1003.1g adds the ability to recvmsg() to query connection pending
* status to recvmsg. We need to add that support in a way thats
* clean when we restucture accept also.
*/
SYSCALL_DEFINE4(accept4, int, fd, struct sockaddr __user *, upeer_sockaddr,
int __user *, upeer_addrlen, int, flags)
{
struct socket *sock, *newsock;
struct file *newfile;
int err, len, newfd, fput_needed;
struct sockaddr_storage address;
if (flags & ~(SOCK_CLOEXEC | SOCK_NONBLOCK))
return -EINVAL;
if (SOCK_NONBLOCK != O_NONBLOCK && (flags & SOCK_NONBLOCK))
flags = (flags & ~SOCK_NONBLOCK) | O_NONBLOCK;
sock = sockfd_lookup_light(fd, &err, &fput_needed);
if (!sock)
goto out;
err = -ENFILE;
if (!(newsock = sock_alloc()))
goto out_put;
newsock->type = sock->type;
newsock->ops = sock->ops;
/*
* We don't need try_module_get here, as the listening socket (sock)
* has the protocol module (sock->ops->owner) held.
*/
__module_get(newsock->ops->owner);
newfd = sock_alloc_fd(&newfile, flags & O_CLOEXEC);
if (unlikely(newfd < 0)) {
err = newfd;
sock_release(newsock);
goto out_put;
}
err = sock_attach_fd(newsock, newfile, flags & O_NONBLOCK);
if (err < 0)
goto out_fd_simple;
err = security_socket_accept(sock, newsock);
if (err)
goto out_fd;
err = sock->ops->accept(sock, newsock, sock->file->f_flags);
if (err < 0)
goto out_fd;
if (upeer_sockaddr) {
if (newsock->ops->getname(newsock, (struct sockaddr *)&address,
&len, 2) < 0) {
err = -ECONNABORTED;
goto out_fd;
}
err = move_addr_to_user((struct sockaddr *)&address,
len, upeer_sockaddr, upeer_addrlen);
if (err < 0)
goto out_fd;
}
/* File flags are not inherited via accept() unlike another OSes. */
fd_install(newfd, newfile);
err = newfd;
out_put:
fput_light(sock->file, fput_needed);
out:
return err;
out_fd_simple:
sock_release(newsock);
put_filp(newfile);
put_unused_fd(newfd);
goto out_put;
out_fd:
fput(newfile);
put_unused_fd(newfd);
goto out_put;
}
SYSCALL_DEFINE3(accept, int, fd, struct sockaddr __user *, upeer_sockaddr,
int __user *, upeer_addrlen)
{
return sys_accept4(fd, upeer_sockaddr, upeer_addrlen, 0);
}
/*
* Attempt to connect to a socket with the server address. The address
* is in user space so we verify it is OK and move it to kernel space.
*
* For 1003.1g we need to add clean support for a bind to AF_UNSPEC to
* break bindings
*
* NOTE: 1003.1g draft 6.3 is broken with respect to AX.25/NetROM and
* other SEQPACKET protocols that take time to connect() as it doesn't
* include the -EINPROGRESS status for such sockets.
*/
SYSCALL_DEFINE3(connect, int, fd, struct sockaddr __user *, uservaddr,
int, addrlen)
{
struct socket *sock;
struct sockaddr_storage address;
int err, fput_needed;
sock = sockfd_lookup_light(fd, &err, &fput_needed);
if (!sock)
goto out;
err = move_addr_to_kernel(uservaddr, addrlen, (struct sockaddr *)&address);
if (err < 0)
goto out_put;
err =
security_socket_connect(sock, (struct sockaddr *)&address, addrlen);
if (err)
goto out_put;
err = sock->ops->connect(sock, (struct sockaddr *)&address, addrlen,
sock->file->f_flags);
out_put:
fput_light(sock->file, fput_needed);
out:
return err;
}
/*
* Get the local address ('name') of a socket object. Move the obtained
* name to user space.
*/
SYSCALL_DEFINE3(getsockname, int, fd, struct sockaddr __user *, usockaddr,
int __user *, usockaddr_len)
{
struct socket *sock;
struct sockaddr_storage address;
int len, err, fput_needed;
sock = sockfd_lookup_light(fd, &err, &fput_needed);
if (!sock)
goto out;
err = security_socket_getsockname(sock);
if (err)
goto out_put;
err = sock->ops->getname(sock, (struct sockaddr *)&address, &len, 0);
if (err)
goto out_put;
err = move_addr_to_user((struct sockaddr *)&address, len, usockaddr, usockaddr_len);
out_put:
fput_light(sock->file, fput_needed);
out:
return err;
}
/*
* Get the remote address ('name') of a socket object. Move the obtained
* name to user space.
*/
SYSCALL_DEFINE3(getpeername, int, fd, struct sockaddr __user *, usockaddr,
int __user *, usockaddr_len)
{
struct socket *sock;
struct sockaddr_storage address;
int len, err, fput_needed;
sock = sockfd_lookup_light(fd, &err, &fput_needed);
if (sock != NULL) {
err = security_socket_getpeername(sock);
if (err) {
fput_light(sock->file, fput_needed);
return err;
}
err =
sock->ops->getname(sock, (struct sockaddr *)&address, &len,
1);
if (!err)
err = move_addr_to_user((struct sockaddr *)&address, len, usockaddr,
usockaddr_len);
fput_light(sock->file, fput_needed);
}
return err;
}
/*
* Send a datagram to a given address. We move the address into kernel
* space and check the user space data area is readable before invoking
* the protocol.
*/
SYSCALL_DEFINE6(sendto, int, fd, void __user *, buff, size_t, len,
unsigned, flags, struct sockaddr __user *, addr,
int, addr_len)
{
struct socket *sock;
struct sockaddr_storage address;
int err;
struct msghdr msg;
struct iovec iov;
int fput_needed;
sock = sockfd_lookup_light(fd, &err, &fput_needed);
if (!sock)
goto out;
iov.iov_base = buff;
iov.iov_len = len;
msg.msg_name = NULL;
msg.msg_iov = &iov;
msg.msg_iovlen = 1;
msg.msg_control = NULL;
msg.msg_controllen = 0;
msg.msg_namelen = 0;
if (addr) {
err = move_addr_to_kernel(addr, addr_len, (struct sockaddr *)&address);
if (err < 0)
goto out_put;
msg.msg_name = (struct sockaddr *)&address;
msg.msg_namelen = addr_len;
}
if (sock->file->f_flags & O_NONBLOCK)
flags |= MSG_DONTWAIT;
msg.msg_flags = flags;
err = sock_sendmsg(sock, &msg, len);
out_put:
fput_light(sock->file, fput_needed);
out:
return err;
}
/*
* Send a datagram down a socket.
*/
SYSCALL_DEFINE4(send, int, fd, void __user *, buff, size_t, len,
unsigned, flags)
{
return sys_sendto(fd, buff, len, flags, NULL, 0);
}
/*
* Receive a frame from the socket and optionally record the address of the
* sender. We verify the buffers are writable and if needed move the
* sender address from kernel to user space.
*/
SYSCALL_DEFINE6(recvfrom, int, fd, void __user *, ubuf, size_t, size,
unsigned, flags, struct sockaddr __user *, addr,
int __user *, addr_len)
{
struct socket *sock;
struct iovec iov;
struct msghdr msg;
struct sockaddr_storage address;
int err, err2;
int fput_needed;
sock = sockfd_lookup_light(fd, &err, &fput_needed);
if (!sock)
goto out;
msg.msg_control = NULL;
msg.msg_controllen = 0;
msg.msg_iovlen = 1;
msg.msg_iov = &iov;
iov.iov_len = size;
iov.iov_base = ubuf;
msg.msg_name = (struct sockaddr *)&address;
msg.msg_namelen = sizeof(address);
if (sock->file->f_flags & O_NONBLOCK)
flags |= MSG_DONTWAIT;
err = sock_recvmsg(sock, &msg, size, flags);
if (err >= 0 && addr != NULL) {
err2 = move_addr_to_user((struct sockaddr *)&address,
msg.msg_namelen, addr, addr_len);
if (err2 < 0)
err = err2;
}
fput_light(sock->file, fput_needed);
out:
return err;
}
/*
* Receive a datagram from a socket.
*/
asmlinkage long sys_recv(int fd, void __user *ubuf, size_t size,
unsigned flags)
{
return sys_recvfrom(fd, ubuf, size, flags, NULL, NULL);
}
/*
* Set a socket option. Because we don't know the option lengths we have
* to pass the user mode parameter for the protocols to sort out.
*/
SYSCALL_DEFINE5(setsockopt, int, fd, int, level, int, optname,
char __user *, optval, int, optlen)
{
int err, fput_needed;
struct socket *sock;
if (optlen < 0)
return -EINVAL;
sock = sockfd_lookup_light(fd, &err, &fput_needed);
if (sock != NULL) {
err = security_socket_setsockopt(sock, level, optname);
if (err)
goto out_put;
if (level == SOL_SOCKET)
err =
sock_setsockopt(sock, level, optname, optval,
optlen);
else
err =
sock->ops->setsockopt(sock, level, optname, optval,
optlen);
out_put:
fput_light(sock->file, fput_needed);
}
return err;
}
/*
* Get a socket option. Because we don't know the option lengths we have
* to pass a user mode parameter for the protocols to sort out.
*/
SYSCALL_DEFINE5(getsockopt, int, fd, int, level, int, optname,
char __user *, optval, int __user *, optlen)
{
int err, fput_needed;
struct socket *sock;
sock = sockfd_lookup_light(fd, &err, &fput_needed);
if (sock != NULL) {
err = security_socket_getsockopt(sock, level, optname);
if (err)
goto out_put;
if (level == SOL_SOCKET)
err =
sock_getsockopt(sock, level, optname, optval,
optlen);
else
err =
sock->ops->getsockopt(sock, level, optname, optval,
optlen);
out_put:
fput_light(sock->file, fput_needed);
}
return err;
}
/*
* Shutdown a socket.
*/
SYSCALL_DEFINE2(shutdown, int, fd, int, how)
{
int err, fput_needed;
struct socket *sock;
sock = sockfd_lookup_light(fd, &err, &fput_needed);
if (sock != NULL) {
err = security_socket_shutdown(sock, how);
if (!err)
err = sock->ops->shutdown(sock, how);
fput_light(sock->file, fput_needed);
}
return err;
}
/* A couple of helpful macros for getting the address of the 32/64 bit
* fields which are the same type (int / unsigned) on our platforms.
*/
#define COMPAT_MSG(msg, member) ((MSG_CMSG_COMPAT & flags) ? &msg##_compat->member : &msg->member)
#define COMPAT_NAMELEN(msg) COMPAT_MSG(msg, msg_namelen)
#define COMPAT_FLAGS(msg) COMPAT_MSG(msg, msg_flags)
/*
* BSD sendmsg interface
*/
SYSCALL_DEFINE3(sendmsg, int, fd, struct msghdr __user *, msg, unsigned, flags)
{
struct compat_msghdr __user *msg_compat =
(struct compat_msghdr __user *)msg;
struct socket *sock;
struct sockaddr_storage address;
struct iovec iovstack[UIO_FASTIOV], *iov = iovstack;
unsigned char ctl[sizeof(struct cmsghdr) + 20]
__attribute__ ((aligned(sizeof(__kernel_size_t))));
/* 20 is size of ipv6_pktinfo */
unsigned char *ctl_buf = ctl;
struct msghdr msg_sys;
int err, ctl_len, iov_size, total_len;
int fput_needed;
err = -EFAULT;
if (MSG_CMSG_COMPAT & flags) {
if (get_compat_msghdr(&msg_sys, msg_compat))
return -EFAULT;
}
else if (copy_from_user(&msg_sys, msg, sizeof(struct msghdr)))
return -EFAULT;
sock = sockfd_lookup_light(fd, &err, &fput_needed);
if (!sock)
goto out;
/* do not move before msg_sys is valid */
err = -EMSGSIZE;
if (msg_sys.msg_iovlen > UIO_MAXIOV)
goto out_put;
/* Check whether to allocate the iovec area */
err = -ENOMEM;
iov_size = msg_sys.msg_iovlen * sizeof(struct iovec);
if (msg_sys.msg_iovlen > UIO_FASTIOV) {
iov = sock_kmalloc(sock->sk, iov_size, GFP_KERNEL);
if (!iov)
goto out_put;
}
/* This will also move the address data into kernel space */
if (MSG_CMSG_COMPAT & flags) {
err = verify_compat_iovec(&msg_sys, iov,
(struct sockaddr *)&address,
VERIFY_READ);
} else
err = verify_iovec(&msg_sys, iov,
(struct sockaddr *)&address,
VERIFY_READ);
if (err < 0)
goto out_freeiov;
total_len = err;
err = -ENOBUFS;
if (msg_sys.msg_controllen > INT_MAX)
goto out_freeiov;
ctl_len = msg_sys.msg_controllen;
if ((MSG_CMSG_COMPAT & flags) && ctl_len) {
err =
cmsghdr_from_user_compat_to_kern(&msg_sys, sock->sk, ctl,
sizeof(ctl));
if (err)
goto out_freeiov;
ctl_buf = msg_sys.msg_control;
ctl_len = msg_sys.msg_controllen;
} else if (ctl_len) {
if (ctl_len > sizeof(ctl)) {
ctl_buf = sock_kmalloc(sock->sk, ctl_len, GFP_KERNEL);
if (ctl_buf == NULL)
goto out_freeiov;
}
err = -EFAULT;
/*
* Careful! Before this, msg_sys.msg_control contains a user pointer.
* Afterwards, it will be a kernel pointer. Thus the compiler-assisted
* checking falls down on this.
*/
if (copy_from_user(ctl_buf, (void __user *)msg_sys.msg_control,
ctl_len))
goto out_freectl;
msg_sys.msg_control = ctl_buf;
}
msg_sys.msg_flags = flags;
if (sock->file->f_flags & O_NONBLOCK)
msg_sys.msg_flags |= MSG_DONTWAIT;
err = sock_sendmsg(sock, &msg_sys, total_len);
out_freectl:
if (ctl_buf != ctl)
sock_kfree_s(sock->sk, ctl_buf, ctl_len);
out_freeiov:
if (iov != iovstack)
sock_kfree_s(sock->sk, iov, iov_size);
out_put:
fput_light(sock->file, fput_needed);
out:
return err;
}
/*
* BSD recvmsg interface
*/
SYSCALL_DEFINE3(recvmsg, int, fd, struct msghdr __user *, msg,
unsigned int, flags)
{
struct compat_msghdr __user *msg_compat =
(struct compat_msghdr __user *)msg;
struct socket *sock;
struct iovec iovstack[UIO_FASTIOV];
struct iovec *iov = iovstack;
struct msghdr msg_sys;
unsigned long cmsg_ptr;
int err, iov_size, total_len, len;
int fput_needed;
/* kernel mode address */
struct sockaddr_storage addr;
/* user mode address pointers */
struct sockaddr __user *uaddr;
int __user *uaddr_len;
if (MSG_CMSG_COMPAT & flags) {
if (get_compat_msghdr(&msg_sys, msg_compat))
return -EFAULT;
}
else if (copy_from_user(&msg_sys, msg, sizeof(struct msghdr)))
return -EFAULT;
sock = sockfd_lookup_light(fd, &err, &fput_needed);
if (!sock)
goto out;
err = -EMSGSIZE;
if (msg_sys.msg_iovlen > UIO_MAXIOV)
goto out_put;
/* Check whether to allocate the iovec area */
err = -ENOMEM;
iov_size = msg_sys.msg_iovlen * sizeof(struct iovec);
if (msg_sys.msg_iovlen > UIO_FASTIOV) {
iov = sock_kmalloc(sock->sk, iov_size, GFP_KERNEL);
if (!iov)
goto out_put;
}
/*
* Save the user-mode address (verify_iovec will change the
* kernel msghdr to use the kernel address space)
*/
uaddr = (__force void __user *)msg_sys.msg_name;
uaddr_len = COMPAT_NAMELEN(msg);
if (MSG_CMSG_COMPAT & flags) {
err = verify_compat_iovec(&msg_sys, iov,
(struct sockaddr *)&addr,
VERIFY_WRITE);
} else
err = verify_iovec(&msg_sys, iov,
(struct sockaddr *)&addr,
VERIFY_WRITE);
if (err < 0)
goto out_freeiov;
total_len = err;
cmsg_ptr = (unsigned long)msg_sys.msg_control;
msg_sys.msg_flags = flags & (MSG_CMSG_CLOEXEC|MSG_CMSG_COMPAT);
if (sock->file->f_flags & O_NONBLOCK)
flags |= MSG_DONTWAIT;
err = sock_recvmsg(sock, &msg_sys, total_len, flags);
if (err < 0)
goto out_freeiov;
len = err;
if (uaddr != NULL) {
err = move_addr_to_user((struct sockaddr *)&addr,
msg_sys.msg_namelen, uaddr,
uaddr_len);
if (err < 0)
goto out_freeiov;
}
err = __put_user((msg_sys.msg_flags & ~MSG_CMSG_COMPAT),
COMPAT_FLAGS(msg));
if (err)
goto out_freeiov;
if (MSG_CMSG_COMPAT & flags)
err = __put_user((unsigned long)msg_sys.msg_control - cmsg_ptr,
&msg_compat->msg_controllen);
else
err = __put_user((unsigned long)msg_sys.msg_control - cmsg_ptr,
&msg->msg_controllen);
if (err)
goto out_freeiov;
err = len;
out_freeiov:
if (iov != iovstack)
sock_kfree_s(sock->sk, iov, iov_size);
out_put:
fput_light(sock->file, fput_needed);
out:
return err;
}
#ifdef __ARCH_WANT_SYS_SOCKETCALL
/* Argument list sizes for sys_socketcall */
#define AL(x) ((x) * sizeof(unsigned long))
static const unsigned char nargs[19]={
AL(0),AL(3),AL(3),AL(3),AL(2),AL(3),
AL(3),AL(3),AL(4),AL(4),AL(4),AL(6),
AL(6),AL(2),AL(5),AL(5),AL(3),AL(3),
AL(4)
};
#undef AL
/*
* System call vectors.
*
* Argument checking cleaned up. Saved 20% in size.
* This function doesn't need to set the kernel lock because
* it is set by the callees.
*/
SYSCALL_DEFINE2(socketcall, int, call, unsigned long __user *, args)
{
unsigned long a[6];
unsigned long a0, a1;
int err;
if (call < 1 || call > SYS_ACCEPT4)
return -EINVAL;
/* copy_from_user should be SMP safe. */
if (copy_from_user(a, args, nargs[call]))
return -EFAULT;
audit_socketcall(nargs[call] / sizeof(unsigned long), a);
a0 = a[0];
a1 = a[1];
switch (call) {
case SYS_SOCKET:
err = sys_socket(a0, a1, a[2]);
break;
case SYS_BIND:
err = sys_bind(a0, (struct sockaddr __user *)a1, a[2]);
break;
case SYS_CONNECT:
err = sys_connect(a0, (struct sockaddr __user *)a1, a[2]);
break;
case SYS_LISTEN:
err = sys_listen(a0, a1);
break;
case SYS_ACCEPT:
err = sys_accept4(a0, (struct sockaddr __user *)a1,
(int __user *)a[2], 0);
break;
case SYS_GETSOCKNAME:
err =
sys_getsockname(a0, (struct sockaddr __user *)a1,
(int __user *)a[2]);
break;
case SYS_GETPEERNAME:
err =
sys_getpeername(a0, (struct sockaddr __user *)a1,
(int __user *)a[2]);
break;
case SYS_SOCKETPAIR:
err = sys_socketpair(a0, a1, a[2], (int __user *)a[3]);
break;
case SYS_SEND:
err = sys_send(a0, (void __user *)a1, a[2], a[3]);
break;
case SYS_SENDTO:
err = sys_sendto(a0, (void __user *)a1, a[2], a[3],
(struct sockaddr __user *)a[4], a[5]);
break;
case SYS_RECV:
err = sys_recv(a0, (void __user *)a1, a[2], a[3]);
break;
case SYS_RECVFROM:
err = sys_recvfrom(a0, (void __user *)a1, a[2], a[3],
(struct sockaddr __user *)a[4],
(int __user *)a[5]);
break;
case SYS_SHUTDOWN:
err = sys_shutdown(a0, a1);
break;
case SYS_SETSOCKOPT:
err = sys_setsockopt(a0, a1, a[2], (char __user *)a[3], a[4]);
break;
case SYS_GETSOCKOPT:
err =
sys_getsockopt(a0, a1, a[2], (char __user *)a[3],
(int __user *)a[4]);
break;
case SYS_SENDMSG:
err = sys_sendmsg(a0, (struct msghdr __user *)a1, a[2]);
break;
case SYS_RECVMSG:
err = sys_recvmsg(a0, (struct msghdr __user *)a1, a[2]);
break;
case SYS_ACCEPT4:
err = sys_accept4(a0, (struct sockaddr __user *)a1,
(int __user *)a[2], a[3]);
break;
default:
err = -EINVAL;
break;
}
return err;
}
#endif /* __ARCH_WANT_SYS_SOCKETCALL */
/**
* sock_register - add a socket protocol handler
* @ops: description of protocol
*
* This function is called by a protocol handler that wants to
* advertise its address family, and have it linked into the
* socket interface. The value ops->family coresponds to the
* socket system call protocol family.
*/
int sock_register(const struct net_proto_family *ops)
{
int err;
if (ops->family >= NPROTO) {
printk(KERN_CRIT "protocol %d >= NPROTO(%d)\n", ops->family,
NPROTO);
return -ENOBUFS;
}
spin_lock(&net_family_lock);
if (net_families[ops->family])
err = -EEXIST;
else {
net_families[ops->family] = ops;
err = 0;
}
spin_unlock(&net_family_lock);
printk(KERN_INFO "NET: Registered protocol family %d\n", ops->family);
return err;
}
/**
* sock_unregister - remove a protocol handler
* @family: protocol family to remove
*
* This function is called by a protocol handler that wants to
* remove its address family, and have it unlinked from the
* new socket creation.
*
* If protocol handler is a module, then it can use module reference
* counts to protect against new references. If protocol handler is not
* a module then it needs to provide its own protection in
* the ops->create routine.
*/
void sock_unregister(int family)
{
BUG_ON(family < 0 || family >= NPROTO);
spin_lock(&net_family_lock);
net_families[family] = NULL;
spin_unlock(&net_family_lock);
synchronize_rcu();
printk(KERN_INFO "NET: Unregistered protocol family %d\n", family);
}
static int __init sock_init(void)
{
/*
* Initialize sock SLAB cache.
*/
sk_init();
/*
* Initialize skbuff SLAB cache
*/
skb_init();
/*
* Initialize the protocols module.
*/
init_inodecache();
register_filesystem(&sock_fs_type);
sock_mnt = kern_mount(&sock_fs_type);
/* The real protocol initialization is performed in later initcalls.
*/
#ifdef CONFIG_NETFILTER
netfilter_init();
#endif
return 0;
}
core_initcall(sock_init); /* early initcall */
#ifdef CONFIG_PROC_FS
void socket_seq_show(struct seq_file *seq)
{
int cpu;
int counter = 0;
for_each_possible_cpu(cpu)
counter += per_cpu(sockets_in_use, cpu);
/* It can be negative, by the way. 8) */
if (counter < 0)
counter = 0;
seq_printf(seq, "sockets: used %d\n", counter);
}
#endif /* CONFIG_PROC_FS */
#ifdef CONFIG_COMPAT
static long compat_sock_ioctl(struct file *file, unsigned cmd,
unsigned long arg)
{
struct socket *sock = file->private_data;
int ret = -ENOIOCTLCMD;
struct sock *sk;
struct net *net;
sk = sock->sk;
net = sock_net(sk);
if (sock->ops->compat_ioctl)
ret = sock->ops->compat_ioctl(sock, cmd, arg);
if (ret == -ENOIOCTLCMD &&
(cmd >= SIOCIWFIRST && cmd <= SIOCIWLAST))
ret = compat_wext_handle_ioctl(net, cmd, arg);
return ret;
}
#endif
int kernel_bind(struct socket *sock, struct sockaddr *addr, int addrlen)
{
return sock->ops->bind(sock, addr, addrlen);
}
int kernel_listen(struct socket *sock, int backlog)
{
return sock->ops->listen(sock, backlog);
}
int kernel_accept(struct socket *sock, struct socket **newsock, int flags)
{
struct sock *sk = sock->sk;
int err;
err = sock_create_lite(sk->sk_family, sk->sk_type, sk->sk_protocol,
newsock);
if (err < 0)
goto done;
err = sock->ops->accept(sock, *newsock, flags);
if (err < 0) {
sock_release(*newsock);
*newsock = NULL;
goto done;
}
(*newsock)->ops = sock->ops;
__module_get((*newsock)->ops->owner);
done:
return err;
}
int kernel_connect(struct socket *sock, struct sockaddr *addr, int addrlen,
int flags)
{
return sock->ops->connect(sock, addr, addrlen, flags);
}
int kernel_getsockname(struct socket *sock, struct sockaddr *addr,
int *addrlen)
{
return sock->ops->getname(sock, addr, addrlen, 0);
}
int kernel_getpeername(struct socket *sock, struct sockaddr *addr,
int *addrlen)
{
return sock->ops->getname(sock, addr, addrlen, 1);
}
int kernel_getsockopt(struct socket *sock, int level, int optname,
char *optval, int *optlen)
{
mm_segment_t oldfs = get_fs();
int err;
set_fs(KERNEL_DS);
if (level == SOL_SOCKET)
err = sock_getsockopt(sock, level, optname, optval, optlen);
else
err = sock->ops->getsockopt(sock, level, optname, optval,
optlen);
set_fs(oldfs);
return err;
}
int kernel_setsockopt(struct socket *sock, int level, int optname,
char *optval, int optlen)
{
mm_segment_t oldfs = get_fs();
int err;
set_fs(KERNEL_DS);
if (level == SOL_SOCKET)
err = sock_setsockopt(sock, level, optname, optval, optlen);
else
err = sock->ops->setsockopt(sock, level, optname, optval,
optlen);
set_fs(oldfs);
return err;
}
int kernel_sendpage(struct socket *sock, struct page *page, int offset,
size_t size, int flags)
{
if (sock->ops->sendpage)
return sock->ops->sendpage(sock, page, offset, size, flags);
return sock_no_sendpage(sock, page, offset, size, flags);
}
int kernel_sock_ioctl(struct socket *sock, int cmd, unsigned long arg)
{
mm_segment_t oldfs = get_fs();
int err;
set_fs(KERNEL_DS);
err = sock->ops->ioctl(sock, cmd, arg);
set_fs(oldfs);
return err;
}
int kernel_sock_shutdown(struct socket *sock, enum sock_shutdown_cmd how)
{
return sock->ops->shutdown(sock, how);
}
EXPORT_SYMBOL(sock_create);
EXPORT_SYMBOL(sock_create_kern);
EXPORT_SYMBOL(sock_create_lite);
EXPORT_SYMBOL(sock_map_fd);
EXPORT_SYMBOL(sock_recvmsg);
EXPORT_SYMBOL(sock_register);
EXPORT_SYMBOL(sock_release);
EXPORT_SYMBOL(sock_sendmsg);
EXPORT_SYMBOL(sock_unregister);
EXPORT_SYMBOL(sock_wake_async);
EXPORT_SYMBOL(sockfd_lookup);
EXPORT_SYMBOL(kernel_sendmsg);
EXPORT_SYMBOL(kernel_recvmsg);
EXPORT_SYMBOL(kernel_bind);
EXPORT_SYMBOL(kernel_listen);
EXPORT_SYMBOL(kernel_accept);
EXPORT_SYMBOL(kernel_connect);
EXPORT_SYMBOL(kernel_getsockname);
EXPORT_SYMBOL(kernel_getpeername);
EXPORT_SYMBOL(kernel_getsockopt);
EXPORT_SYMBOL(kernel_setsockopt);
EXPORT_SYMBOL(kernel_sendpage);
EXPORT_SYMBOL(kernel_sock_ioctl);
EXPORT_SYMBOL(kernel_sock_shutdown);