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/*
* 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, <bir7@leland.Stanford.Edu>
* 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.
*
*/
#include <linux/config.h>
#include <linux/mm.h>
#include <linux/smp_lock.h>
#include <linux/socket.h>
#include <linux/file.h>
#include <linux/net.h>
#include <linux/interrupt.h>
#include <linux/netdevice.h>
#include <linux/proc_fs.h>
#include <linux/wanrouter.h>
#include <linux/netlink.h>
#include <linux/rtnetlink.h>
#include <linux/init.h>
#include <linux/poll.h>
#include <linux/cache.h>
#include <linux/module.h>
#include <linux/highmem.h>
#if defined(CONFIG_KMOD) && defined(CONFIG_NET)
#include <linux/kmod.h>
#endif
#include <asm/uaccess.h>
#include <net/sock.h>
#include <net/scm.h>
#include <linux/netfilter.h>
static int sock_no_open(struct inode *irrelevant, struct file *dontcare);
static loff_t sock_lseek(struct file *file, loff_t offset, int whence);
static ssize_t sock_read(struct file *file, char *buf,
size_t size, loff_t *ppos);
static ssize_t sock_write(struct file *file, const char *buf,
size_t size, loff_t *ppos);
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 int sock_ioctl(struct inode *inode, struct file *file,
unsigned int cmd, unsigned long arg);
static int sock_fasync(int fd, struct file *filp, int on);
static ssize_t sock_readv(struct file *file, const struct iovec *vector,
unsigned long count, loff_t *ppos);
static ssize_t sock_writev(struct file *file, const struct iovec *vector,
unsigned long count, loff_t *ppos);
static ssize_t sock_sendpage(struct file *file, struct page *page,
int offset, size_t size, loff_t *ppos, int more);
/*
* 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 struct file_operations socket_file_ops = {
llseek: sock_lseek,
read: sock_read,
write: sock_write,
poll: sock_poll,
ioctl: sock_ioctl,
mmap: sock_mmap,
open: sock_no_open, /* special open code to disallow open via /proc */
release: sock_close,
fasync: sock_fasync,
readv: sock_readv,
writev: sock_writev,
sendpage: sock_sendpage
};
/*
* The protocol list. Each protocol is registered in here.
*/
static struct net_proto_family *net_families[NPROTO];
#ifdef CONFIG_SMP
static atomic_t net_family_lockct = ATOMIC_INIT(0);
static spinlock_t net_family_lock = SPIN_LOCK_UNLOCKED;
/* The strategy is: modifications net_family vector are short, do not
sleep and veeery rare, but read access should be free of any exclusive
locks.
*/
static void net_family_write_lock(void)
{
spin_lock(&net_family_lock);
while (atomic_read(&net_family_lockct) != 0) {
spin_unlock(&net_family_lock);
current->policy |= SCHED_YIELD;
schedule();
spin_lock(&net_family_lock);
}
}
static __inline__ void net_family_write_unlock(void)
{
spin_unlock(&net_family_lock);
}
static __inline__ void net_family_read_lock(void)
{
atomic_inc(&net_family_lockct);
spin_unlock_wait(&net_family_lock);
}
static __inline__ void net_family_read_unlock(void)
{
atomic_dec(&net_family_lockct);
}
#else
#define net_family_write_lock() do { } while(0)
#define net_family_write_unlock() do { } while(0)
#define net_family_read_lock() do { } while(0)
#define net_family_read_unlock() do { } while(0)
#endif
/*
* Statistics counters of the socket lists
*/
static union {
int counter;
char __pad[SMP_CACHE_BYTES];
} sockets_in_use[NR_CPUS] __cacheline_aligned = {{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 *uaddr, int ulen, void *kaddr)
{
if(ulen<0||ulen>MAX_SOCK_ADDR)
return -EINVAL;
if(ulen==0)
return 0;
if(copy_from_user(kaddr,uaddr,ulen))
return -EFAULT;
return 0;
}
/**
* 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(void *kaddr, int klen, void *uaddr, int *ulen)
{
int err;
int len;
if((err=get_user(len, ulen)))
return err;
if(len>klen)
len=klen;
if(len<0 || len> MAX_SOCK_ADDR)
return -EINVAL;
if(len)
{
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 int sockfs_statfs(struct super_block *sb, struct statfs *buf)
{
buf->f_type = SOCKFS_MAGIC;
buf->f_bsize = 1024;
buf->f_namelen = 255;
return 0;
}
static struct super_operations sockfs_ops = {
statfs: sockfs_statfs,
};
static struct super_block * sockfs_read_super(struct super_block *sb, void *data, int silent)
{
struct inode *root = new_inode(sb);
if (!root)
return NULL;
root->i_mode = S_IFDIR | S_IRUSR | S_IWUSR;
root->i_uid = root->i_gid = 0;
root->i_atime = root->i_mtime = root->i_ctime = CURRENT_TIME;
sb->s_blocksize = 1024;
sb->s_blocksize_bits = 10;
sb->s_magic = SOCKFS_MAGIC;
sb->s_op = &sockfs_ops;
sb->s_root = d_alloc(NULL, &(const struct qstr) { "socket:", 7, 0 });
if (!sb->s_root) {
iput(root);
return NULL;
}
sb->s_root->d_sb = sb;
sb->s_root->d_parent = sb->s_root;
d_instantiate(sb->s_root, root);
return sb;
}
static struct vfsmount *sock_mnt;
static DECLARE_FSTYPE(sock_fs_type, "sockfs", sockfs_read_super, FS_NOMOUNT);
static int sockfs_delete_dentry(struct dentry *dentry)
{
return 1;
}
static struct dentry_operations sockfs_dentry_operations = {
d_delete: sockfs_delete_dentry,
};
/*
* Obtains the first available file descriptor and sets it up for use.
*
* This functions creates file structure and maps it to fd space
* of 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 inincrement ref. count on file by 1.
*
* In any case returned fd MAY BE not valid!
* This race condition is inavoidable
* with shared fd spaces, we cannot solve is inside kernel,
* but we take care of internal coherence yet.
*/
static int sock_map_fd(struct socket *sock)
{
int fd;
struct qstr this;
char name[32];
/*
* Find a file descriptor suitable for return to the user.
*/
fd = get_unused_fd();
if (fd >= 0) {
struct file *file = get_empty_filp();
if (!file) {
put_unused_fd(fd);
fd = -ENFILE;
goto out;
}
sprintf(name, "[%lu]", sock->inode->i_ino);
this.name = name;
this.len = strlen(name);
this.hash = sock->inode->i_ino;
file->f_dentry = d_alloc(sock_mnt->mnt_sb->s_root, &this);
if (!file->f_dentry) {
put_filp(file);
put_unused_fd(fd);
fd = -ENOMEM;
goto out;
}
file->f_dentry->d_op = &sockfs_dentry_operations;
d_add(file->f_dentry, sock->inode);
file->f_vfsmnt = mntget(sock_mnt);
sock->file = file;
file->f_op = sock->inode->i_fop = &socket_file_ops;
file->f_mode = 3;
file->f_flags = O_RDWR;
file->f_pos = 0;
fd_install(fd, file);
}
out:
return fd;
}
extern __inline__ struct socket *socki_lookup(struct inode *inode)
{
return &inode->u.socket_i;
}
/**
* 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 inode *inode;
struct socket *sock;
if (!(file = fget(fd)))
{
*err = -EBADF;
return NULL;
}
inode = file->f_dentry->d_inode;
if (!inode->i_sock || !(sock = socki_lookup(inode)))
{
*err = -ENOTSOCK;
fput(file);
return NULL;
}
if (sock->file != file) {
printk(KERN_ERR "socki_lookup: socket file changed!\n");
sock->file = file;
}
return sock;
}
extern __inline__ void sockfd_put(struct socket *sock)
{
fput(sock->file);
}
/**
* 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.
*/
struct socket *sock_alloc(void)
{
struct inode * inode;
struct socket * sock;
inode = get_empty_inode();
if (!inode)
return NULL;
inode->i_sb = sock_mnt->mnt_sb;
sock = socki_lookup(inode);
inode->i_mode = S_IFSOCK|S_IRWXUGO;
inode->i_sock = 1;
inode->i_uid = current->fsuid;
inode->i_gid = current->fsgid;
sock->inode = inode;
init_waitqueue_head(&sock->wait);
sock->fasync_list = NULL;
sock->state = SS_UNCONNECTED;
sock->flags = 0;
sock->ops = NULL;
sock->sk = NULL;
sock->file = NULL;
sockets_in_use[smp_processor_id()].counter++;
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;
}
/**
* 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)
sock->ops->release(sock);
if (sock->fasync_list)
printk(KERN_ERR "sock_release: fasync list not empty!\n");
sockets_in_use[smp_processor_id()].counter--;
if (!sock->file) {
iput(sock->inode);
return;
}
sock->file=NULL;
}
int sock_sendmsg(struct socket *sock, struct msghdr *msg, int size)
{
int err;
struct scm_cookie scm;
err = scm_send(sock, msg, &scm);
if (err >= 0) {
err = sock->ops->sendmsg(sock, msg, size, &scm);
scm_destroy(&scm);
}
return err;
}
int sock_recvmsg(struct socket *sock, struct msghdr *msg, int size, int flags)
{
struct scm_cookie scm;
memset(&scm, 0, sizeof(scm));
size = sock->ops->recvmsg(sock, msg, size, flags, &scm);
if (size >= 0)
scm_recv(sock, msg, &scm, flags);
return size;
}
/*
* Sockets are not seekable.
*/
static loff_t sock_lseek(struct file *file, loff_t offset, int whence)
{
return -ESPIPE;
}
/*
* Read data from a socket. ubuf is a user mode pointer. We make sure the user
* area ubuf...ubuf+size-1 is writable before asking the protocol.
*/
static ssize_t sock_read(struct file *file, char *ubuf,
size_t size, loff_t *ppos)
{
struct socket *sock;
struct iovec iov;
struct msghdr msg;
int flags;
if (ppos != &file->f_pos)
return -ESPIPE;
if (size==0) /* Match SYS5 behaviour */
return 0;
sock = socki_lookup(file->f_dentry->d_inode);
msg.msg_name=NULL;
msg.msg_namelen=0;
msg.msg_iov=&iov;
msg.msg_iovlen=1;
msg.msg_control=NULL;
msg.msg_controllen=0;
iov.iov_base=ubuf;
iov.iov_len=size;
flags = !(file->f_flags & O_NONBLOCK) ? 0 : MSG_DONTWAIT;
return sock_recvmsg(sock, &msg, size, flags);
}
/*
* Write data to a socket. We verify that the user area ubuf..ubuf+size-1
* is readable by the user process.
*/
static ssize_t sock_write(struct file *file, const char *ubuf,
size_t size, loff_t *ppos)
{
struct socket *sock;
struct msghdr msg;
struct iovec iov;
if (ppos != &file->f_pos)
return -ESPIPE;
if(size==0) /* Match SYS5 behaviour */
return 0;
sock = socki_lookup(file->f_dentry->d_inode);
msg.msg_name=NULL;
msg.msg_namelen=0;
msg.msg_iov=&iov;
msg.msg_iovlen=1;
msg.msg_control=NULL;
msg.msg_controllen=0;
msg.msg_flags=!(file->f_flags & O_NONBLOCK) ? 0 : MSG_DONTWAIT;
if (sock->type == SOCK_SEQPACKET)
msg.msg_flags |= MSG_EOR;
iov.iov_base=(void *)ubuf;
iov.iov_len=size;
return sock_sendmsg(sock, &msg, size);
}
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;
if (ppos != &file->f_pos)
return -ESPIPE;
sock = socki_lookup(file->f_dentry->d_inode);
flags = !(file->f_flags & O_NONBLOCK) ? 0 : MSG_DONTWAIT;
if (more)
flags |= MSG_MORE;
return sock->ops->sendpage(sock, page, offset, size, flags);
}
int sock_readv_writev(int type, struct inode * inode, struct file * file,
const struct iovec * iov, long count, long size)
{
struct msghdr msg;
struct socket *sock;
sock = socki_lookup(inode);
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 = count;
msg.msg_flags = (file->f_flags & O_NONBLOCK) ? MSG_DONTWAIT : 0;
/* read() does a VERIFY_WRITE */
if (type == VERIFY_WRITE)
return sock_recvmsg(sock, &msg, size, msg.msg_flags);
if (sock->type == SOCK_SEQPACKET)
msg.msg_flags |= MSG_EOR;
return sock_sendmsg(sock, &msg, size);
}
static ssize_t sock_readv(struct file *file, const struct iovec *vector,
unsigned long count, loff_t *ppos)
{
size_t tot_len = 0;
int i;
for (i = 0 ; i < count ; i++)
tot_len += vector[i].iov_len;
return sock_readv_writev(VERIFY_WRITE, file->f_dentry->d_inode,
file, vector, count, tot_len);
}
static ssize_t sock_writev(struct file *file, const struct iovec *vector,
unsigned long count, loff_t *ppos)
{
size_t tot_len = 0;
int i;
for (i = 0 ; i < count ; i++)
tot_len += vector[i].iov_len;
return sock_readv_writev(VERIFY_READ, file->f_dentry->d_inode,
file, vector, count, tot_len);
}
/*
* 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.
*/
int sock_ioctl(struct inode *inode, struct file *file, unsigned int cmd,
unsigned long arg)
{
struct socket *sock;
int err;
unlock_kernel();
sock = socki_lookup(inode);
err = sock->ops->ioctl(sock, cmd, arg);
lock_kernel();
return err;
}
/* 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 = socki_lookup(file->f_dentry->d_inode);
return sock->ops->poll(file, sock, wait);
}
static int sock_mmap(struct file * file, struct vm_area_struct * vma)
{
struct socket *sock = socki_lookup(file->f_dentry->d_inode);
return sock->ops->mmap(file, sock, vma);
}
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_fasync(-1, filp, 0);
sock_release(socki_lookup(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->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->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=(struct fasync_struct *)kmalloc(sizeof(struct fasync_struct), GFP_KERNEL);
if(fna==NULL)
return -ENOMEM;
}
sock = socki_lookup(filp->f_dentry->d_inode);
if ((sk=sock->sk) == NULL)
return -EINVAL;
lock_sock(sk);
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->callback_lock);
fa->fa_fd=fd;
write_unlock_bh(&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->callback_lock);
sock->fasync_list=fna;
write_unlock_bh(&sk->callback_lock);
}
else
{
if (fa!=NULL)
{
write_lock_bh(&sk->callback_lock);
*prev=fa->fa_next;
write_unlock_bh(&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 1:
if (test_bit(SOCK_ASYNC_WAITDATA, &sock->flags))
break;
goto call_kill;
case 2:
if (!test_and_clear_bit(SOCK_ASYNC_NOSPACE, &sock->flags))
break;
/* fall through */
case 0:
call_kill:
__kill_fasync(sock->fasync_list, SIGIO, band);
break;
case 3:
__kill_fasync(sock->fasync_list, SIGURG, band);
}
return 0;
}
int sock_create(int family, int type, int protocol, struct socket **res)
{
int i;
struct socket *sock;
/*
* 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;
}
#if defined(CONFIG_KMOD) && defined(CONFIG_NET)
/* 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)
{
char module_name[30];
sprintf(module_name,"net-pf-%d",family);
request_module(module_name);
}
#endif
net_family_read_lock();
if (net_families[family] == NULL) {
i = -EAFNOSUPPORT;
goto out;
}
/*
* 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.
*/
if (!(sock = sock_alloc()))
{
printk(KERN_WARNING "socket: no more sockets\n");
i = -ENFILE; /* Not exactly a match, but its the
closest posix thing */
goto out;
}
sock->type = type;
if ((i = net_families[family]->create(sock, protocol)) < 0)
{
sock_release(sock);
goto out;
}
*res = sock;
out:
net_family_read_unlock();
return i;
}
asmlinkage long sys_socket(int family, int type, int protocol)
{
int retval;
struct socket *sock;
retval = sock_create(family, type, protocol, &sock);
if (retval < 0)
goto out;
retval = sock_map_fd(sock);
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.
*/
asmlinkage long sys_socketpair(int family, int type, int protocol, int usockvec[2])
{
struct socket *sock1, *sock2;
int fd1, fd2, err;
/*
* 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 = fd2 = -1;
err = sock_map_fd(sock1);
if (err < 0)
goto out_release_both;
fd1 = err;
err = sock_map_fd(sock2);
if (err < 0)
goto out_close_1;
fd2 = err;
/* 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_close_1:
sock_release(sock2);
sys_close(fd1);
return err;
out_release_both:
sock_release(sock2);
out_release_1:
sock_release(sock1);
out:
return err;
}
/*
* 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).
*/
asmlinkage long sys_bind(int fd, struct sockaddr *umyaddr, int addrlen)
{
struct socket *sock;
char address[MAX_SOCK_ADDR];
int err;
if((sock = sockfd_lookup(fd,&err))!=NULL)
{
if((err=move_addr_to_kernel(umyaddr,addrlen,address))>=0)
err = sock->ops->bind(sock, (struct sockaddr *)address, addrlen);
sockfd_put(sock);
}
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.
*/
asmlinkage long sys_listen(int fd, int backlog)
{
struct socket *sock;
int err;
if ((sock = sockfd_lookup(fd, &err)) != NULL) {
if ((unsigned) backlog > SOMAXCONN)
backlog = SOMAXCONN;
err=sock->ops->listen(sock, backlog);
sockfd_put(sock);
}
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.
*/
asmlinkage long sys_accept(int fd, struct sockaddr *upeer_sockaddr, int *upeer_addrlen)
{
struct socket *sock, *newsock;
int err, len;
char address[MAX_SOCK_ADDR];
sock = sockfd_lookup(fd, &err);
if (!sock)
goto out;
err = -EMFILE;
if (!(newsock = sock_alloc()))
goto out_put;
newsock->type = sock->type;
newsock->ops = sock->ops;
err = sock->ops->accept(sock, newsock, sock->file->f_flags);
if (err < 0)
goto out_release;
if (upeer_sockaddr) {
if(newsock->ops->getname(newsock, (struct sockaddr *)address, &len, 2)<0) {
err = -ECONNABORTED;
goto out_release;
}
err = move_addr_to_user(address, len, upeer_sockaddr, upeer_addrlen);
if (err < 0)
goto out_release;
}
/* File flags are not inherited via accept() unlike another OSes. */
if ((err = sock_map_fd(newsock)) < 0)
goto out_release;
out_put:
sockfd_put(sock);
out:
return err;
out_release:
sock_release(newsock);
goto out_put;
}
/*
* 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.
*/
asmlinkage long sys_connect(int fd, struct sockaddr *uservaddr, int addrlen)
{
struct socket *sock;
char address[MAX_SOCK_ADDR];
int err;
sock = sockfd_lookup(fd, &err);
if (!sock)
goto out;
err = move_addr_to_kernel(uservaddr, addrlen, address);
if (err < 0)
goto out_put;
err = sock->ops->connect(sock, (struct sockaddr *) address, addrlen,
sock->file->f_flags);
out_put:
sockfd_put(sock);
out:
return err;
}
/*
* Get the local address ('name') of a socket object. Move the obtained
* name to user space.
*/
asmlinkage long sys_getsockname(int fd, struct sockaddr *usockaddr, int *usockaddr_len)
{
struct socket *sock;
char address[MAX_SOCK_ADDR];
int len, err;
sock = sockfd_lookup(fd, &err);
if (!sock)
goto out;
err = sock->ops->getname(sock, (struct sockaddr *)address, &len, 0);
if (err)
goto out_put;
err = move_addr_to_user(address, len, usockaddr, usockaddr_len);
out_put:
sockfd_put(sock);
out:
return err;
}
/*
* Get the remote address ('name') of a socket object. Move the obtained
* name to user space.
*/
asmlinkage long sys_getpeername(int fd, struct sockaddr *usockaddr, int *usockaddr_len)
{
struct socket *sock;
char address[MAX_SOCK_ADDR];
int len, err;
if ((sock = sockfd_lookup(fd, &err))!=NULL)
{
err = sock->ops->getname(sock, (struct sockaddr *)address, &len, 1);
if (!err)
err=move_addr_to_user(address,len, usockaddr, usockaddr_len);
sockfd_put(sock);
}
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.
*/
asmlinkage long sys_sendto(int fd, void * buff, size_t len, unsigned flags,
struct sockaddr *addr, int addr_len)
{
struct socket *sock;
char address[MAX_SOCK_ADDR];
int err;
struct msghdr msg;
struct iovec iov;
sock = sockfd_lookup(fd, &err);
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, address);
if (err < 0)
goto out_put;
msg.msg_name=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:
sockfd_put(sock);
out:
return err;
}
/*
* Send a datagram down a socket.
*/
asmlinkage long sys_send(int fd, void * 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.
*/
asmlinkage long sys_recvfrom(int fd, void * ubuf, size_t size, unsigned flags,
struct sockaddr *addr, int *addr_len)
{
struct socket *sock;
struct iovec iov;
struct msghdr msg;
char address[MAX_SOCK_ADDR];
int err,err2;
sock = sockfd_lookup(fd, &err);
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=address;
msg.msg_namelen=MAX_SOCK_ADDR;
if (sock->file->f_flags & O_NONBLOCK)
flags |= MSG_DONTWAIT;
err=sock_recvmsg(sock, &msg, size, flags);
if(err >= 0 && addr != NULL && msg.msg_namelen)
{
err2=move_addr_to_user(address, msg.msg_namelen, addr, addr_len);
if(err2<0)
err=err2;
}
sockfd_put(sock);
out:
return err;
}
/*
* Receive a datagram from a socket.
*/
asmlinkage long sys_recv(int fd, void * 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.
*/
asmlinkage long sys_setsockopt(int fd, int level, int optname, char *optval, int optlen)
{
int err;
struct socket *sock;
if (optlen < 0)
return -EINVAL;
if ((sock = sockfd_lookup(fd, &err))!=NULL)
{
if (level == SOL_SOCKET)
err=sock_setsockopt(sock,level,optname,optval,optlen);
else
err=sock->ops->setsockopt(sock, level, optname, optval, optlen);
sockfd_put(sock);
}
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.
*/
asmlinkage long sys_getsockopt(int fd, int level, int optname, char *optval, int *optlen)
{
int err;
int len;
struct socket *sock;
if ((sock = sockfd_lookup(fd, &err))!=NULL)
{
/* XXX: insufficient for SMP, but should be redundant anyway */
if (get_user(len, optlen))
err = -EFAULT;
else
if (len < 0)
err = -EINVAL;
else
if (level == SOL_SOCKET)
err=sock_getsockopt(sock,level,optname,optval,optlen);
else
err=sock->ops->getsockopt(sock, level, optname, optval, optlen);
sockfd_put(sock);
}
return err;
}
/*
* Shutdown a socket.
*/
asmlinkage long sys_shutdown(int fd, int how)
{
int err;
struct socket *sock;
if ((sock = sockfd_lookup(fd, &err))!=NULL)
{
err=sock->ops->shutdown(sock, how);
sockfd_put(sock);
}
return err;
}
/*
* BSD sendmsg interface
*/
asmlinkage long sys_sendmsg(int fd, struct msghdr *msg, unsigned flags)
{
struct socket *sock;
char address[MAX_SOCK_ADDR];
struct iovec iovstack[UIO_FASTIOV], *iov = iovstack;
unsigned char ctl[sizeof(struct cmsghdr) + 20]; /* 20 is size of ipv6_pktinfo */
unsigned char *ctl_buf = ctl;
struct msghdr msg_sys;
int err, ctl_len, iov_size, total_len;
err = -EFAULT;
if (copy_from_user(&msg_sys,msg,sizeof(struct msghdr)))
goto out;
sock = sockfd_lookup(fd, &err);
if (!sock)
goto out;
/* do not move before msg_sys is valid */
err = -EINVAL;
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 */
err = verify_iovec(&msg_sys, iov, 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 (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;
if (copy_from_user(ctl_buf, 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:
sockfd_put(sock);
out:
return err;
}
/*
* BSD recvmsg interface
*/
asmlinkage long sys_recvmsg(int fd, struct msghdr *msg, unsigned int flags)
{
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;
/* kernel mode address */
char addr[MAX_SOCK_ADDR];
/* user mode address pointers */
struct sockaddr *uaddr;
int *uaddr_len;
err=-EFAULT;
if (copy_from_user(&msg_sys,msg,sizeof(struct msghdr)))
goto out;
sock = sockfd_lookup(fd, &err);
if (!sock)
goto out;
err = -EINVAL;
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 = msg_sys.msg_name;
uaddr_len = &msg->msg_namelen;
err = verify_iovec(&msg_sys, iov, addr, VERIFY_WRITE);
if (err < 0)
goto out_freeiov;
total_len=err;
cmsg_ptr = (unsigned long)msg_sys.msg_control;
msg_sys.msg_flags = 0;
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 && msg_sys.msg_namelen) {
err = move_addr_to_user(addr, msg_sys.msg_namelen, uaddr, uaddr_len);
if (err < 0)
goto out_freeiov;
}
err = __put_user(msg_sys.msg_flags, &msg->msg_flags);
if (err)
goto out_freeiov;
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:
sockfd_put(sock);
out:
return err;
}
/*
* Perform a file control on a socket file descriptor.
*
* Doesn't acquire a fd lock, because no network fcntl
* function sleeps currently.
*/
int sock_fcntl(struct file *filp, unsigned int cmd, unsigned long arg)
{
struct socket *sock;
sock = socki_lookup (filp->f_dentry->d_inode);
if (sock && sock->ops)
return sock_no_fcntl(sock, cmd, arg);
return(-EINVAL);
}
/* Argument list sizes for sys_socketcall */
#define AL(x) ((x) * sizeof(unsigned long))
static unsigned char nargs[18]={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)};
#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.
*/
asmlinkage long sys_socketcall(int call, unsigned long *args)
{
unsigned long a[6];
unsigned long a0,a1;
int err;
if(call<1||call>SYS_RECVMSG)
return -EINVAL;
/* copy_from_user should be SMP safe. */
if (copy_from_user(a, args, nargs[call]))
return -EFAULT;
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 *)a1, a[2]);
break;
case SYS_CONNECT:
err = sys_connect(a0, (struct sockaddr *)a1, a[2]);
break;
case SYS_LISTEN:
err = sys_listen(a0,a1);
break;
case SYS_ACCEPT:
err = sys_accept(a0,(struct sockaddr *)a1, (int *)a[2]);
break;
case SYS_GETSOCKNAME:
err = sys_getsockname(a0,(struct sockaddr *)a1, (int *)a[2]);
break;
case SYS_GETPEERNAME:
err = sys_getpeername(a0, (struct sockaddr *)a1, (int *)a[2]);
break;
case SYS_SOCKETPAIR:
err = sys_socketpair(a0,a1, a[2], (int *)a[3]);
break;
case SYS_SEND:
err = sys_send(a0, (void *)a1, a[2], a[3]);
break;
case SYS_SENDTO:
err = sys_sendto(a0,(void *)a1, a[2], a[3],
(struct sockaddr *)a[4], a[5]);
break;
case SYS_RECV:
err = sys_recv(a0, (void *)a1, a[2], a[3]);
break;
case SYS_RECVFROM:
err = sys_recvfrom(a0, (void *)a1, a[2], a[3],
(struct sockaddr *)a[4], (int *)a[5]);
break;
case SYS_SHUTDOWN:
err = sys_shutdown(a0,a1);
break;
case SYS_SETSOCKOPT:
err = sys_setsockopt(a0, a1, a[2], (char *)a[3], a[4]);
break;
case SYS_GETSOCKOPT:
err = sys_getsockopt(a0, a1, a[2], (char *)a[3], (int *)a[4]);
break;
case SYS_SENDMSG:
err = sys_sendmsg(a0, (struct msghdr *) a1, a[2]);
break;
case SYS_RECVMSG:
err = sys_recvmsg(a0, (struct msghdr *) a1, a[2]);
break;
default:
err = -EINVAL;
break;
}
return err;
}
/*
* This function is called by a protocol handler that wants to
* advertise its address family, and have it linked into the
* SOCKET module.
*/
int sock_register(struct net_proto_family *ops)
{
int err;
if (ops->family >= NPROTO) {
printk(KERN_CRIT "protocol %d >= NPROTO(%d)\n", ops->family, NPROTO);
return -ENOBUFS;
}
net_family_write_lock();
err = -EEXIST;
if (net_families[ops->family] == NULL) {
net_families[ops->family]=ops;
err = 0;
}
net_family_write_unlock();
return err;
}
/*
* This function is called by a protocol handler that wants to
* remove its address family, and have it unlinked from the
* SOCKET module.
*/
int sock_unregister(int family)
{
if (family < 0 || family >= NPROTO)
return -1;
net_family_write_lock();
net_families[family]=NULL;
net_family_write_unlock();
return 0;
}
extern void sk_init(void);
#ifdef CONFIG_WAN_ROUTER
extern void wanrouter_init(void);
#endif
#ifdef CONFIG_BLUEZ
extern void bluez_init(void);
#endif
void __init sock_init(void)
{
int i;
printk(KERN_INFO "Linux NET4.0 for Linux 2.4\n");
printk(KERN_INFO "Based upon Swansea University Computer Society NET3.039\n");
/*
* Initialize all address (protocol) families.
*/
for (i = 0; i < NPROTO; i++)
net_families[i] = NULL;
/*
* Initialize sock SLAB cache.
*/
sk_init();
#ifdef SLAB_SKB
/*
* Initialize skbuff SLAB cache
*/
skb_init();
#endif
/*
* Wan router layer.
*/
#ifdef CONFIG_WAN_ROUTER
wanrouter_init();
#endif
/*
* Initialize the protocols module.
*/
register_filesystem(&sock_fs_type);
sock_mnt = kern_mount(&sock_fs_type);
/* The real protocol initialization is performed when
* do_initcalls is run.
*/
/*
* The netlink device handler may be needed early.
*/
#ifdef CONFIG_NET
rtnetlink_init();
#endif
#ifdef CONFIG_NETLINK_DEV
init_netlink();
#endif
#ifdef CONFIG_NETFILTER
netfilter_init();
#endif
#ifdef CONFIG_BLUEZ
bluez_init();
#endif
}
int socket_get_info(char *buffer, char **start, off_t offset, int length)
{
int len, cpu;
int counter = 0;
for (cpu=0; cpu<smp_num_cpus; cpu++)
counter += sockets_in_use[cpu_logical_map(cpu)].counter;
/* It can be negative, by the way. 8) */
if (counter < 0)
counter = 0;
len = sprintf(buffer, "sockets: used %d\n", counter);
if (offset >= len)
{
*start = buffer;
return 0;
}
*start = buffer + offset;
len -= offset;
if (len > length)
len = length;
if (len < 0)
len = 0;
return len;
}
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