/* * 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/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/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); /* * 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, }; /* * 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, 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 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(void *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 > MAX_SOCK_ADDR) 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 kmem_cache *cachep, unsigned long flags) { 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 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 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 fd; fd = get_unused_fd(); 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) { struct qstr name = { .name = "" }; file->f_path.dentry = d_alloc(sock_mnt->mnt_sb->s_root, &name); if (unlikely(!file->f_path.dentry)) return -ENOMEM; file->f_path.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 */ file->f_path.dentry->d_flags &= ~DCACHE_UNHASHED; d_instantiate(file->f_path.dentry, SOCK_INODE(sock)); file->f_path.mnt = mntget(sock_mnt); file->f_mapping = file->f_path.dentry->d_inode->i_mapping; sock->file = file; file->f_op = SOCK_INODE(sock)->i_fop = &socket_file_ops; file->f_mode = FMODE_READ | FMODE_WRITE; file->f_flags = O_RDWR; file->f_pos = 0; file->private_data = sock; return 0; } int sock_map_fd(struct socket *sock) { struct file *newfile; int fd = sock_alloc_fd(&newfile); if (likely(fd >= 0)) { int err = sock_attach_fd(sock, newfile); 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); inode->i_mode = S_IFSOCK | S_IRWXUGO; inode->i_uid = current->fsuid; inode->i_gid = current->fsgid; get_cpu_var(sockets_in_use)++; put_cpu_var(sockets_in_use); 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"); get_cpu_var(sockets_in_use)--; put_cpu_var(sockets_in_use); if (!sock->file) { iput(SOCK_INODE(sock)); return; } sock->file = NULL; } 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; } /* * 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) { ktime_t kt = skb->tstamp; if (!sock_flag(sk, SOCK_RCVTSTAMPNS)) { struct timeval tv; /* Race occurred between timestamp enabling and packet receiving. Fill in the current time for now. */ if (kt.tv64 == 0) kt = ktime_get_real(); skb->tstamp = kt; tv = ktime_to_timeval(kt); put_cmsg(msg, SOL_SOCKET, SCM_TIMESTAMP, sizeof(tv), &tv); } else { struct timespec ts; /* Race occurred between timestamp enabling and packet receiving. Fill in the current time for now. */ if (kt.tv64 == 0) kt = ktime_get_real(); skb->tstamp = kt; ts = ktime_to_timespec(kt); put_cmsg(msg, SOL_SOCKET, SCM_TIMESTAMPNS, 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 sock->ops->sendpage(sock, page, offset, size, 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 = sk->sk_net; 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"); if (dlci_ioctl_hook) { mutex_lock(&dlci_ioctl_mutex); 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_fasync(-1, filp, 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); 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 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; } 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; #if defined(CONFIG_KMOD) /* 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); } 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 __user *usockvec) { struct socket *sock1, *sock2; int fd1, fd2, err; struct file *newfile1, *newfile2; /* * 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); if (unlikely(fd1 < 0)) goto out_release_both; fd2 = sock_alloc_fd(&newfile2); if (unlikely(fd2 < 0)) { put_filp(newfile1); put_unused_fd(fd1); goto out_release_both; } err = sock_attach_fd(sock1, newfile1); if (unlikely(err < 0)) { goto out_fd2; } err = sock_attach_fd(sock2, newfile2); if (unlikely(err < 0)) { fput(newfile1); goto out_fd1; } err = audit_fd_pair(fd1, fd2); if (err < 0) { fput(newfile1); fput(newfile2); goto out_fd; } 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); out_fd: 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). */ asmlinkage long sys_bind(int fd, struct sockaddr __user *umyaddr, int addrlen) { struct socket *sock; char address[MAX_SOCK_ADDR]; int err, fput_needed; sock = sockfd_lookup_light(fd, &err, &fput_needed); if (sock) { err = move_addr_to_kernel(umyaddr, addrlen, 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. */ int sysctl_somaxconn __read_mostly = SOMAXCONN; asmlinkage long sys_listen(int fd, int backlog) { struct socket *sock; int err, fput_needed; sock = sockfd_lookup_light(fd, &err, &fput_needed); if (sock) { if ((unsigned)backlog > sysctl_somaxconn) backlog = sysctl_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. */ asmlinkage long sys_accept(int fd, struct sockaddr __user *upeer_sockaddr, int __user *upeer_addrlen) { struct socket *sock, *newsock; struct file *newfile; int err, len, newfd, fput_needed; char address[MAX_SOCK_ADDR]; 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); if (unlikely(newfd < 0)) { err = newfd; sock_release(newsock); goto out_put; } err = sock_attach_fd(newsock, newfile); 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(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; security_socket_post_accept(sock, newsock); 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; } /* * 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 __user *uservaddr, int addrlen) { struct socket *sock; char address[MAX_SOCK_ADDR]; int err, fput_needed; sock = sockfd_lookup_light(fd, &err, &fput_needed); if (!sock) goto out; err = move_addr_to_kernel(uservaddr, addrlen, 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. */ asmlinkage long sys_getsockname(int fd, struct sockaddr __user *usockaddr, int __user *usockaddr_len) { struct socket *sock; char address[MAX_SOCK_ADDR]; 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(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. */ asmlinkage long sys_getpeername(int fd, struct sockaddr __user *usockaddr, int __user *usockaddr_len) { struct socket *sock; char address[MAX_SOCK_ADDR]; 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(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. */ asmlinkage long sys_sendto(int fd, void __user *buff, size_t len, unsigned flags, struct sockaddr __user *addr, int addr_len) { struct socket *sock; char address[MAX_SOCK_ADDR]; int err; struct msghdr msg; struct iovec iov; int fput_needed; struct file *sock_file; sock_file = fget_light(fd, &fput_needed); err = -EBADF; if (!sock_file) goto out; sock = sock_from_file(sock_file, &err); if (!sock) goto out_put; 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: fput_light(sock_file, fput_needed); out: return err; } /* * Send a datagram down a socket. */ asmlinkage long sys_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. */ asmlinkage long sys_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; char address[MAX_SOCK_ADDR]; int err, err2; struct file *sock_file; int fput_needed; sock_file = fget_light(fd, &fput_needed); err = -EBADF; if (!sock_file) goto out; sock = sock_from_file(sock_file, &err); if (!sock) goto out_put; 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) { err2 = move_addr_to_user(address, msg.msg_namelen, addr, addr_len); if (err2 < 0) err = err2; } out_put: 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. */ asmlinkage long sys_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. */ asmlinkage long sys_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. */ asmlinkage long sys_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 */ asmlinkage long sys_sendmsg(int fd, struct msghdr __user *msg, unsigned flags) { struct compat_msghdr __user *msg_compat = (struct compat_msghdr __user *)msg; struct socket *sock; char address[MAX_SOCK_ADDR]; 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, address, VERIFY_READ); } else 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 ((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 */ asmlinkage long sys_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 */ char addr[MAX_SOCK_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 = (void __user *)msg_sys.msg_name; uaddr_len = COMPAT_NAMELEN(msg); if (MSG_CMSG_COMPAT & flags) { err = verify_compat_iovec(&msg_sys, iov, addr, VERIFY_WRITE); } else 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 = 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(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[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 __user *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; err = audit_socketcall(nargs[call] / sizeof(unsigned long), a); if (err) return err; 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_accept(a0, (struct sockaddr __user *)a1, (int __user *)a[2]); 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; 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; if (sock->ops->compat_ioctl) ret = sock->ops->compat_ioctl(sock, 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); goto done; } (*newsock)->ops = sock->ops; 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; } /* ABI emulation layers need these two */ EXPORT_SYMBOL(move_addr_to_kernel); EXPORT_SYMBOL(move_addr_to_user); 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);