diff options
author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 15:20:36 -0700 |
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committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 15:20:36 -0700 |
commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /net/unix |
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Diffstat (limited to 'net/unix')
-rw-r--r-- | net/unix/Makefile | 8 | ||||
-rw-r--r-- | net/unix/af_unix.c | 2098 | ||||
-rw-r--r-- | net/unix/garbage.c | 312 | ||||
-rw-r--r-- | net/unix/sysctl_net_unix.c | 60 |
4 files changed, 2478 insertions, 0 deletions
diff --git a/net/unix/Makefile b/net/unix/Makefile new file mode 100644 index 00000000000..b852a2bde9a --- /dev/null +++ b/net/unix/Makefile @@ -0,0 +1,8 @@ +# +# Makefile for the Linux unix domain socket layer. +# + +obj-$(CONFIG_UNIX) += unix.o + +unix-y := af_unix.o garbage.o +unix-$(CONFIG_SYSCTL) += sysctl_net_unix.o diff --git a/net/unix/af_unix.c b/net/unix/af_unix.c new file mode 100644 index 00000000000..acc73fe6869 --- /dev/null +++ b/net/unix/af_unix.c @@ -0,0 +1,2098 @@ +/* + * NET4: Implementation of BSD Unix domain sockets. + * + * Authors: Alan Cox, <alan.cox@linux.org> + * + * 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. + * + * Version: $Id: af_unix.c,v 1.133 2002/02/08 03:57:19 davem Exp $ + * + * Fixes: + * Linus Torvalds : Assorted bug cures. + * Niibe Yutaka : async I/O support. + * Carsten Paeth : PF_UNIX check, address fixes. + * Alan Cox : Limit size of allocated blocks. + * Alan Cox : Fixed the stupid socketpair bug. + * Alan Cox : BSD compatibility fine tuning. + * Alan Cox : Fixed a bug in connect when interrupted. + * Alan Cox : Sorted out a proper draft version of + * file descriptor passing hacked up from + * Mike Shaver's work. + * Marty Leisner : Fixes to fd passing + * Nick Nevin : recvmsg bugfix. + * Alan Cox : Started proper garbage collector + * Heiko EiBfeldt : Missing verify_area check + * Alan Cox : Started POSIXisms + * Andreas Schwab : Replace inode by dentry for proper + * reference counting + * Kirk Petersen : Made this a module + * Christoph Rohland : Elegant non-blocking accept/connect algorithm. + * Lots of bug fixes. + * Alexey Kuznetosv : Repaired (I hope) bugs introduces + * by above two patches. + * Andrea Arcangeli : If possible we block in connect(2) + * if the max backlog of the listen socket + * is been reached. This won't break + * old apps and it will avoid huge amount + * of socks hashed (this for unix_gc() + * performances reasons). + * Security fix that limits the max + * number of socks to 2*max_files and + * the number of skb queueable in the + * dgram receiver. + * Artur Skawina : Hash function optimizations + * Alexey Kuznetsov : Full scale SMP. Lot of bugs are introduced 8) + * Malcolm Beattie : Set peercred for socketpair + * Michal Ostrowski : Module initialization cleanup. + * Arnaldo C. Melo : Remove MOD_{INC,DEC}_USE_COUNT, + * the core infrastructure is doing that + * for all net proto families now (2.5.69+) + * + * + * Known differences from reference BSD that was tested: + * + * [TO FIX] + * ECONNREFUSED is not returned from one end of a connected() socket to the + * other the moment one end closes. + * fstat() doesn't return st_dev=0, and give the blksize as high water mark + * and a fake inode identifier (nor the BSD first socket fstat twice bug). + * [NOT TO FIX] + * accept() returns a path name even if the connecting socket has closed + * in the meantime (BSD loses the path and gives up). + * accept() returns 0 length path for an unbound connector. BSD returns 16 + * and a null first byte in the path (but not for gethost/peername - BSD bug ??) + * socketpair(...SOCK_RAW..) doesn't panic the kernel. + * BSD af_unix apparently has connect forgetting to block properly. + * (need to check this with the POSIX spec in detail) + * + * Differences from 2.0.0-11-... (ANK) + * Bug fixes and improvements. + * - client shutdown killed server socket. + * - removed all useless cli/sti pairs. + * + * Semantic changes/extensions. + * - generic control message passing. + * - SCM_CREDENTIALS control message. + * - "Abstract" (not FS based) socket bindings. + * Abstract names are sequences of bytes (not zero terminated) + * started by 0, so that this name space does not intersect + * with BSD names. + */ + +#include <linux/module.h> +#include <linux/config.h> +#include <linux/kernel.h> +#include <linux/major.h> +#include <linux/signal.h> +#include <linux/sched.h> +#include <linux/errno.h> +#include <linux/string.h> +#include <linux/stat.h> +#include <linux/dcache.h> +#include <linux/namei.h> +#include <linux/socket.h> +#include <linux/un.h> +#include <linux/fcntl.h> +#include <linux/termios.h> +#include <linux/sockios.h> +#include <linux/net.h> +#include <linux/in.h> +#include <linux/fs.h> +#include <linux/slab.h> +#include <asm/uaccess.h> +#include <linux/skbuff.h> +#include <linux/netdevice.h> +#include <net/sock.h> +#include <linux/tcp.h> +#include <net/af_unix.h> +#include <linux/proc_fs.h> +#include <linux/seq_file.h> +#include <net/scm.h> +#include <linux/init.h> +#include <linux/poll.h> +#include <linux/smp_lock.h> +#include <linux/rtnetlink.h> +#include <linux/mount.h> +#include <net/checksum.h> +#include <linux/security.h> + +int sysctl_unix_max_dgram_qlen = 10; + +struct hlist_head unix_socket_table[UNIX_HASH_SIZE + 1]; +DEFINE_RWLOCK(unix_table_lock); +static atomic_t unix_nr_socks = ATOMIC_INIT(0); + +#define unix_sockets_unbound (&unix_socket_table[UNIX_HASH_SIZE]) + +#define UNIX_ABSTRACT(sk) (unix_sk(sk)->addr->hash != UNIX_HASH_SIZE) + +/* + * SMP locking strategy: + * hash table is protected with rwlock unix_table_lock + * each socket state is protected by separate rwlock. + */ + +static inline unsigned unix_hash_fold(unsigned hash) +{ + hash ^= hash>>16; + hash ^= hash>>8; + return hash&(UNIX_HASH_SIZE-1); +} + +#define unix_peer(sk) (unix_sk(sk)->peer) + +static inline int unix_our_peer(struct sock *sk, struct sock *osk) +{ + return unix_peer(osk) == sk; +} + +static inline int unix_may_send(struct sock *sk, struct sock *osk) +{ + return (unix_peer(osk) == NULL || unix_our_peer(sk, osk)); +} + +static struct sock *unix_peer_get(struct sock *s) +{ + struct sock *peer; + + unix_state_rlock(s); + peer = unix_peer(s); + if (peer) + sock_hold(peer); + unix_state_runlock(s); + return peer; +} + +static inline void unix_release_addr(struct unix_address *addr) +{ + if (atomic_dec_and_test(&addr->refcnt)) + kfree(addr); +} + +/* + * Check unix socket name: + * - should be not zero length. + * - if started by not zero, should be NULL terminated (FS object) + * - if started by zero, it is abstract name. + */ + +static int unix_mkname(struct sockaddr_un * sunaddr, int len, unsigned *hashp) +{ + if (len <= sizeof(short) || len > sizeof(*sunaddr)) + return -EINVAL; + if (!sunaddr || sunaddr->sun_family != AF_UNIX) + return -EINVAL; + if (sunaddr->sun_path[0]) { + /* + * This may look like an off by one error but it is a bit more + * subtle. 108 is the longest valid AF_UNIX path for a binding. + * sun_path[108] doesnt as such exist. However in kernel space + * we are guaranteed that it is a valid memory location in our + * kernel address buffer. + */ + ((char *)sunaddr)[len]=0; + len = strlen(sunaddr->sun_path)+1+sizeof(short); + return len; + } + + *hashp = unix_hash_fold(csum_partial((char*)sunaddr, len, 0)); + return len; +} + +static void __unix_remove_socket(struct sock *sk) +{ + sk_del_node_init(sk); +} + +static void __unix_insert_socket(struct hlist_head *list, struct sock *sk) +{ + BUG_TRAP(sk_unhashed(sk)); + sk_add_node(sk, list); +} + +static inline void unix_remove_socket(struct sock *sk) +{ + write_lock(&unix_table_lock); + __unix_remove_socket(sk); + write_unlock(&unix_table_lock); +} + +static inline void unix_insert_socket(struct hlist_head *list, struct sock *sk) +{ + write_lock(&unix_table_lock); + __unix_insert_socket(list, sk); + write_unlock(&unix_table_lock); +} + +static struct sock *__unix_find_socket_byname(struct sockaddr_un *sunname, + int len, int type, unsigned hash) +{ + struct sock *s; + struct hlist_node *node; + + sk_for_each(s, node, &unix_socket_table[hash ^ type]) { + struct unix_sock *u = unix_sk(s); + + if (u->addr->len == len && + !memcmp(u->addr->name, sunname, len)) + goto found; + } + s = NULL; +found: + return s; +} + +static inline struct sock *unix_find_socket_byname(struct sockaddr_un *sunname, + int len, int type, + unsigned hash) +{ + struct sock *s; + + read_lock(&unix_table_lock); + s = __unix_find_socket_byname(sunname, len, type, hash); + if (s) + sock_hold(s); + read_unlock(&unix_table_lock); + return s; +} + +static struct sock *unix_find_socket_byinode(struct inode *i) +{ + struct sock *s; + struct hlist_node *node; + + read_lock(&unix_table_lock); + sk_for_each(s, node, + &unix_socket_table[i->i_ino & (UNIX_HASH_SIZE - 1)]) { + struct dentry *dentry = unix_sk(s)->dentry; + + if(dentry && dentry->d_inode == i) + { + sock_hold(s); + goto found; + } + } + s = NULL; +found: + read_unlock(&unix_table_lock); + return s; +} + +static inline int unix_writable(struct sock *sk) +{ + return (atomic_read(&sk->sk_wmem_alloc) << 2) <= sk->sk_sndbuf; +} + +static void unix_write_space(struct sock *sk) +{ + read_lock(&sk->sk_callback_lock); + if (unix_writable(sk)) { + if (sk->sk_sleep && waitqueue_active(sk->sk_sleep)) + wake_up_interruptible(sk->sk_sleep); + sk_wake_async(sk, 2, POLL_OUT); + } + read_unlock(&sk->sk_callback_lock); +} + +/* When dgram socket disconnects (or changes its peer), we clear its receive + * queue of packets arrived from previous peer. First, it allows to do + * flow control based only on wmem_alloc; second, sk connected to peer + * may receive messages only from that peer. */ +static void unix_dgram_disconnected(struct sock *sk, struct sock *other) +{ + if (skb_queue_len(&sk->sk_receive_queue)) { + skb_queue_purge(&sk->sk_receive_queue); + wake_up_interruptible_all(&unix_sk(sk)->peer_wait); + + /* If one link of bidirectional dgram pipe is disconnected, + * we signal error. Messages are lost. Do not make this, + * when peer was not connected to us. + */ + if (!sock_flag(other, SOCK_DEAD) && unix_peer(other) == sk) { + other->sk_err = ECONNRESET; + other->sk_error_report(other); + } + } +} + +static void unix_sock_destructor(struct sock *sk) +{ + struct unix_sock *u = unix_sk(sk); + + skb_queue_purge(&sk->sk_receive_queue); + + BUG_TRAP(!atomic_read(&sk->sk_wmem_alloc)); + BUG_TRAP(sk_unhashed(sk)); + BUG_TRAP(!sk->sk_socket); + if (!sock_flag(sk, SOCK_DEAD)) { + printk("Attempt to release alive unix socket: %p\n", sk); + return; + } + + if (u->addr) + unix_release_addr(u->addr); + + atomic_dec(&unix_nr_socks); +#ifdef UNIX_REFCNT_DEBUG + printk(KERN_DEBUG "UNIX %p is destroyed, %d are still alive.\n", sk, atomic_read(&unix_nr_socks)); +#endif +} + +static int unix_release_sock (struct sock *sk, int embrion) +{ + struct unix_sock *u = unix_sk(sk); + struct dentry *dentry; + struct vfsmount *mnt; + struct sock *skpair; + struct sk_buff *skb; + int state; + + unix_remove_socket(sk); + + /* Clear state */ + unix_state_wlock(sk); + sock_orphan(sk); + sk->sk_shutdown = SHUTDOWN_MASK; + dentry = u->dentry; + u->dentry = NULL; + mnt = u->mnt; + u->mnt = NULL; + state = sk->sk_state; + sk->sk_state = TCP_CLOSE; + unix_state_wunlock(sk); + + wake_up_interruptible_all(&u->peer_wait); + + skpair=unix_peer(sk); + + if (skpair!=NULL) { + if (sk->sk_type == SOCK_STREAM || sk->sk_type == SOCK_SEQPACKET) { + unix_state_wlock(skpair); + /* No more writes */ + skpair->sk_shutdown = SHUTDOWN_MASK; + if (!skb_queue_empty(&sk->sk_receive_queue) || embrion) + skpair->sk_err = ECONNRESET; + unix_state_wunlock(skpair); + skpair->sk_state_change(skpair); + read_lock(&skpair->sk_callback_lock); + sk_wake_async(skpair,1,POLL_HUP); + read_unlock(&skpair->sk_callback_lock); + } + sock_put(skpair); /* It may now die */ + unix_peer(sk) = NULL; + } + + /* Try to flush out this socket. Throw out buffers at least */ + + while ((skb = skb_dequeue(&sk->sk_receive_queue)) != NULL) { + if (state==TCP_LISTEN) + unix_release_sock(skb->sk, 1); + /* passed fds are erased in the kfree_skb hook */ + kfree_skb(skb); + } + + if (dentry) { + dput(dentry); + mntput(mnt); + } + + sock_put(sk); + + /* ---- Socket is dead now and most probably destroyed ---- */ + + /* + * Fixme: BSD difference: In BSD all sockets connected to use get + * ECONNRESET and we die on the spot. In Linux we behave + * like files and pipes do and wait for the last + * dereference. + * + * Can't we simply set sock->err? + * + * What the above comment does talk about? --ANK(980817) + */ + + if (atomic_read(&unix_tot_inflight)) + unix_gc(); /* Garbage collect fds */ + + return 0; +} + +static int unix_listen(struct socket *sock, int backlog) +{ + int err; + struct sock *sk = sock->sk; + struct unix_sock *u = unix_sk(sk); + + err = -EOPNOTSUPP; + if (sock->type!=SOCK_STREAM && sock->type!=SOCK_SEQPACKET) + goto out; /* Only stream/seqpacket sockets accept */ + err = -EINVAL; + if (!u->addr) + goto out; /* No listens on an unbound socket */ + unix_state_wlock(sk); + if (sk->sk_state != TCP_CLOSE && sk->sk_state != TCP_LISTEN) + goto out_unlock; + if (backlog > sk->sk_max_ack_backlog) + wake_up_interruptible_all(&u->peer_wait); + sk->sk_max_ack_backlog = backlog; + sk->sk_state = TCP_LISTEN; + /* set credentials so connect can copy them */ + sk->sk_peercred.pid = current->tgid; + sk->sk_peercred.uid = current->euid; + sk->sk_peercred.gid = current->egid; + err = 0; + +out_unlock: + unix_state_wunlock(sk); +out: + return err; +} + +static int unix_release(struct socket *); +static int unix_bind(struct socket *, struct sockaddr *, int); +static int unix_stream_connect(struct socket *, struct sockaddr *, + int addr_len, int flags); +static int unix_socketpair(struct socket *, struct socket *); +static int unix_accept(struct socket *, struct socket *, int); +static int unix_getname(struct socket *, struct sockaddr *, int *, int); +static unsigned int unix_poll(struct file *, struct socket *, poll_table *); +static int unix_ioctl(struct socket *, unsigned int, unsigned long); +static int unix_shutdown(struct socket *, int); +static int unix_stream_sendmsg(struct kiocb *, struct socket *, + struct msghdr *, size_t); +static int unix_stream_recvmsg(struct kiocb *, struct socket *, + struct msghdr *, size_t, int); +static int unix_dgram_sendmsg(struct kiocb *, struct socket *, + struct msghdr *, size_t); +static int unix_dgram_recvmsg(struct kiocb *, struct socket *, + struct msghdr *, size_t, int); +static int unix_dgram_connect(struct socket *, struct sockaddr *, + int, int); +static int unix_seqpacket_sendmsg(struct kiocb *, struct socket *, + struct msghdr *, size_t); + +static struct proto_ops unix_stream_ops = { + .family = PF_UNIX, + .owner = THIS_MODULE, + .release = unix_release, + .bind = unix_bind, + .connect = unix_stream_connect, + .socketpair = unix_socketpair, + .accept = unix_accept, + .getname = unix_getname, + .poll = unix_poll, + .ioctl = unix_ioctl, + .listen = unix_listen, + .shutdown = unix_shutdown, + .setsockopt = sock_no_setsockopt, + .getsockopt = sock_no_getsockopt, + .sendmsg = unix_stream_sendmsg, + .recvmsg = unix_stream_recvmsg, + .mmap = sock_no_mmap, + .sendpage = sock_no_sendpage, +}; + +static struct proto_ops unix_dgram_ops = { + .family = PF_UNIX, + .owner = THIS_MODULE, + .release = unix_release, + .bind = unix_bind, + .connect = unix_dgram_connect, + .socketpair = unix_socketpair, + .accept = sock_no_accept, + .getname = unix_getname, + .poll = datagram_poll, + .ioctl = unix_ioctl, + .listen = sock_no_listen, + .shutdown = unix_shutdown, + .setsockopt = sock_no_setsockopt, + .getsockopt = sock_no_getsockopt, + .sendmsg = unix_dgram_sendmsg, + .recvmsg = unix_dgram_recvmsg, + .mmap = sock_no_mmap, + .sendpage = sock_no_sendpage, +}; + +static struct proto_ops unix_seqpacket_ops = { + .family = PF_UNIX, + .owner = THIS_MODULE, + .release = unix_release, + .bind = unix_bind, + .connect = unix_stream_connect, + .socketpair = unix_socketpair, + .accept = unix_accept, + .getname = unix_getname, + .poll = datagram_poll, + .ioctl = unix_ioctl, + .listen = unix_listen, + .shutdown = unix_shutdown, + .setsockopt = sock_no_setsockopt, + .getsockopt = sock_no_getsockopt, + .sendmsg = unix_seqpacket_sendmsg, + .recvmsg = unix_dgram_recvmsg, + .mmap = sock_no_mmap, + .sendpage = sock_no_sendpage, +}; + +static struct proto unix_proto = { + .name = "UNIX", + .owner = THIS_MODULE, + .obj_size = sizeof(struct unix_sock), +}; + +static struct sock * unix_create1(struct socket *sock) +{ + struct sock *sk = NULL; + struct unix_sock *u; + + if (atomic_read(&unix_nr_socks) >= 2*files_stat.max_files) + goto out; + + sk = sk_alloc(PF_UNIX, GFP_KERNEL, &unix_proto, 1); + if (!sk) + goto out; + + atomic_inc(&unix_nr_socks); + + sock_init_data(sock,sk); + + sk->sk_write_space = unix_write_space; + sk->sk_max_ack_backlog = sysctl_unix_max_dgram_qlen; + sk->sk_destruct = unix_sock_destructor; + u = unix_sk(sk); + u->dentry = NULL; + u->mnt = NULL; + rwlock_init(&u->lock); + atomic_set(&u->inflight, sock ? 0 : -1); + init_MUTEX(&u->readsem); /* single task reading lock */ + init_waitqueue_head(&u->peer_wait); + unix_insert_socket(unix_sockets_unbound, sk); +out: + return sk; +} + +static int unix_create(struct socket *sock, int protocol) +{ + if (protocol && protocol != PF_UNIX) + return -EPROTONOSUPPORT; + + sock->state = SS_UNCONNECTED; + + switch (sock->type) { + case SOCK_STREAM: + sock->ops = &unix_stream_ops; + break; + /* + * Believe it or not BSD has AF_UNIX, SOCK_RAW though + * nothing uses it. + */ + case SOCK_RAW: + sock->type=SOCK_DGRAM; + case SOCK_DGRAM: + sock->ops = &unix_dgram_ops; + break; + case SOCK_SEQPACKET: + sock->ops = &unix_seqpacket_ops; + break; + default: + return -ESOCKTNOSUPPORT; + } + + return unix_create1(sock) ? 0 : -ENOMEM; +} + +static int unix_release(struct socket *sock) +{ + struct sock *sk = sock->sk; + + if (!sk) + return 0; + + sock->sk = NULL; + + return unix_release_sock (sk, 0); +} + +static int unix_autobind(struct socket *sock) +{ + struct sock *sk = sock->sk; + struct unix_sock *u = unix_sk(sk); + static u32 ordernum = 1; + struct unix_address * addr; + int err; + + down(&u->readsem); + + err = 0; + if (u->addr) + goto out; + + err = -ENOMEM; + addr = kmalloc(sizeof(*addr) + sizeof(short) + 16, GFP_KERNEL); + if (!addr) + goto out; + + memset(addr, 0, sizeof(*addr) + sizeof(short) + 16); + addr->name->sun_family = AF_UNIX; + atomic_set(&addr->refcnt, 1); + +retry: + addr->len = sprintf(addr->name->sun_path+1, "%05x", ordernum) + 1 + sizeof(short); + addr->hash = unix_hash_fold(csum_partial((void*)addr->name, addr->len, 0)); + + write_lock(&unix_table_lock); + ordernum = (ordernum+1)&0xFFFFF; + + if (__unix_find_socket_byname(addr->name, addr->len, sock->type, + addr->hash)) { + write_unlock(&unix_table_lock); + /* Sanity yield. It is unusual case, but yet... */ + if (!(ordernum&0xFF)) + yield(); + goto retry; + } + addr->hash ^= sk->sk_type; + + __unix_remove_socket(sk); + u->addr = addr; + __unix_insert_socket(&unix_socket_table[addr->hash], sk); + write_unlock(&unix_table_lock); + err = 0; + +out: up(&u->readsem); + return err; +} + +static struct sock *unix_find_other(struct sockaddr_un *sunname, int len, + int type, unsigned hash, int *error) +{ + struct sock *u; + struct nameidata nd; + int err = 0; + + if (sunname->sun_path[0]) { + err = path_lookup(sunname->sun_path, LOOKUP_FOLLOW, &nd); + if (err) + goto fail; + err = permission(nd.dentry->d_inode,MAY_WRITE, &nd); + if (err) + goto put_fail; + + err = -ECONNREFUSED; + if (!S_ISSOCK(nd.dentry->d_inode->i_mode)) + goto put_fail; + u=unix_find_socket_byinode(nd.dentry->d_inode); + if (!u) + goto put_fail; + + if (u->sk_type == type) + touch_atime(nd.mnt, nd.dentry); + + path_release(&nd); + + err=-EPROTOTYPE; + if (u->sk_type != type) { + sock_put(u); + goto fail; + } + } else { + err = -ECONNREFUSED; + u=unix_find_socket_byname(sunname, len, type, hash); + if (u) { + struct dentry *dentry; + dentry = unix_sk(u)->dentry; + if (dentry) + touch_atime(unix_sk(u)->mnt, dentry); + } else + goto fail; + } + return u; + +put_fail: + path_release(&nd); +fail: + *error=err; + return NULL; +} + + +static int unix_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len) +{ + struct sock *sk = sock->sk; + struct unix_sock *u = unix_sk(sk); + struct sockaddr_un *sunaddr=(struct sockaddr_un *)uaddr; + struct dentry * dentry = NULL; + struct nameidata nd; + int err; + unsigned hash; + struct unix_address *addr; + struct hlist_head *list; + + err = -EINVAL; + if (sunaddr->sun_family != AF_UNIX) + goto out; + + if (addr_len==sizeof(short)) { + err = unix_autobind(sock); + goto out; + } + + err = unix_mkname(sunaddr, addr_len, &hash); + if (err < 0) + goto out; + addr_len = err; + + down(&u->readsem); + + err = -EINVAL; + if (u->addr) + goto out_up; + + err = -ENOMEM; + addr = kmalloc(sizeof(*addr)+addr_len, GFP_KERNEL); + if (!addr) + goto out_up; + + memcpy(addr->name, sunaddr, addr_len); + addr->len = addr_len; + addr->hash = hash ^ sk->sk_type; + atomic_set(&addr->refcnt, 1); + + if (sunaddr->sun_path[0]) { + unsigned int mode; + err = 0; + /* + * Get the parent directory, calculate the hash for last + * component. + */ + err = path_lookup(sunaddr->sun_path, LOOKUP_PARENT, &nd); + if (err) + goto out_mknod_parent; + /* + * Yucky last component or no last component at all? + * (foo/., foo/.., /////) + */ + err = -EEXIST; + if (nd.last_type != LAST_NORM) + goto out_mknod; + /* + * Lock the directory. + */ + down(&nd.dentry->d_inode->i_sem); + /* + * Do the final lookup. + */ + dentry = lookup_hash(&nd.last, nd.dentry); + err = PTR_ERR(dentry); + if (IS_ERR(dentry)) + goto out_mknod_unlock; + err = -ENOENT; + /* + * Special case - lookup gave negative, but... we had foo/bar/ + * From the vfs_mknod() POV we just have a negative dentry - + * all is fine. Let's be bastards - you had / on the end, you've + * been asking for (non-existent) directory. -ENOENT for you. + */ + if (nd.last.name[nd.last.len] && !dentry->d_inode) + goto out_mknod_dput; + /* + * All right, let's create it. + */ + mode = S_IFSOCK | + (SOCK_INODE(sock)->i_mode & ~current->fs->umask); + err = vfs_mknod(nd.dentry->d_inode, dentry, mode, 0); + if (err) + goto out_mknod_dput; + up(&nd.dentry->d_inode->i_sem); + dput(nd.dentry); + nd.dentry = dentry; + + addr->hash = UNIX_HASH_SIZE; + } + + write_lock(&unix_table_lock); + + if (!sunaddr->sun_path[0]) { + err = -EADDRINUSE; + if (__unix_find_socket_byname(sunaddr, addr_len, + sk->sk_type, hash)) { + unix_release_addr(addr); + goto out_unlock; + } + + list = &unix_socket_table[addr->hash]; + } else { + list = &unix_socket_table[dentry->d_inode->i_ino & (UNIX_HASH_SIZE-1)]; + u->dentry = nd.dentry; + u->mnt = nd.mnt; + } + + err = 0; + __unix_remove_socket(sk); + u->addr = addr; + __unix_insert_socket(list, sk); + +out_unlock: + write_unlock(&unix_table_lock); +out_up: + up(&u->readsem); +out: + return err; + +out_mknod_dput: + dput(dentry); +out_mknod_unlock: + up(&nd.dentry->d_inode->i_sem); +out_mknod: + path_release(&nd); +out_mknod_parent: + if (err==-EEXIST) + err=-EADDRINUSE; + unix_release_addr(addr); + goto out_up; +} + +static int unix_dgram_connect(struct socket *sock, struct sockaddr *addr, + int alen, int flags) +{ + struct sock *sk = sock->sk; + struct sockaddr_un *sunaddr=(struct sockaddr_un*)addr; + struct sock *other; + unsigned hash; + int err; + + if (addr->sa_family != AF_UNSPEC) { + err = unix_mkname(sunaddr, alen, &hash); + if (err < 0) + goto out; + alen = err; + + if (test_bit(SOCK_PASSCRED, &sock->flags) && + !unix_sk(sk)->addr && (err = unix_autobind(sock)) != 0) + goto out; + + other=unix_find_other(sunaddr, alen, sock->type, hash, &err); + if (!other) + goto out; + + unix_state_wlock(sk); + + err = -EPERM; + if (!unix_may_send(sk, other)) + goto out_unlock; + + err = security_unix_may_send(sk->sk_socket, other->sk_socket); + if (err) + goto out_unlock; + + } else { + /* + * 1003.1g breaking connected state with AF_UNSPEC + */ + other = NULL; + unix_state_wlock(sk); + } + + /* + * If it was connected, reconnect. + */ + if (unix_peer(sk)) { + struct sock *old_peer = unix_peer(sk); + unix_peer(sk)=other; + unix_state_wunlock(sk); + + if (other != old_peer) + unix_dgram_disconnected(sk, old_peer); + sock_put(old_peer); + } else { + unix_peer(sk)=other; + unix_state_wunlock(sk); + } + return 0; + +out_unlock: + unix_state_wunlock(sk); + sock_put(other); +out: + return err; +} + +static long unix_wait_for_peer(struct sock *other, long timeo) +{ + struct unix_sock *u = unix_sk(other); + int sched; + DEFINE_WAIT(wait); + + prepare_to_wait_exclusive(&u->peer_wait, &wait, TASK_INTERRUPTIBLE); + + sched = !sock_flag(other, SOCK_DEAD) && + !(other->sk_shutdown & RCV_SHUTDOWN) && + (skb_queue_len(&other->sk_receive_queue) > + other->sk_max_ack_backlog); + + unix_state_runlock(other); + + if (sched) + timeo = schedule_timeout(timeo); + + finish_wait(&u->peer_wait, &wait); + return timeo; +} + +static int unix_stream_connect(struct socket *sock, struct sockaddr *uaddr, + int addr_len, int flags) +{ + struct sockaddr_un *sunaddr=(struct sockaddr_un *)uaddr; + struct sock *sk = sock->sk; + struct unix_sock *u = unix_sk(sk), *newu, *otheru; + struct sock *newsk = NULL; + struct sock *other = NULL; + struct sk_buff *skb = NULL; + unsigned hash; + int st; + int err; + long timeo; + + err = unix_mkname(sunaddr, addr_len, &hash); + if (err < 0) + goto out; + addr_len = err; + + if (test_bit(SOCK_PASSCRED, &sock->flags) + && !u->addr && (err = unix_autobind(sock)) != 0) + goto out; + + timeo = sock_sndtimeo(sk, flags & O_NONBLOCK); + + /* First of all allocate resources. + If we will make it after state is locked, + we will have to recheck all again in any case. + */ + + err = -ENOMEM; + + /* create new sock for complete connection */ + newsk = unix_create1(NULL); + if (newsk == NULL) + goto out; + + /* Allocate skb for sending to listening sock */ + skb = sock_wmalloc(newsk, 1, 0, GFP_KERNEL); + if (skb == NULL) + goto out; + +restart: + /* Find listening sock. */ + other = unix_find_other(sunaddr, addr_len, sk->sk_type, hash, &err); + if (!other) + goto out; + + /* Latch state of peer */ + unix_state_rlock(other); + + /* Apparently VFS overslept socket death. Retry. */ + if (sock_flag(other, SOCK_DEAD)) { + unix_state_runlock(other); + sock_put(other); + goto restart; + } + + err = -ECONNREFUSED; + if (other->sk_state != TCP_LISTEN) + goto out_unlock; + + if (skb_queue_len(&other->sk_receive_queue) > + other->sk_max_ack_backlog) { + err = -EAGAIN; + if (!timeo) + goto out_unlock; + + timeo = unix_wait_for_peer(other, timeo); + + err = sock_intr_errno(timeo); + if (signal_pending(current)) + goto out; + sock_put(other); + goto restart; + } + + /* Latch our state. + + It is tricky place. We need to grab write lock and cannot + drop lock on peer. It is dangerous because deadlock is + possible. Connect to self case and simultaneous + attempt to connect are eliminated by checking socket + state. other is TCP_LISTEN, if sk is TCP_LISTEN we + check this before attempt to grab lock. + + Well, and we have to recheck the state after socket locked. + */ + st = sk->sk_state; + + switch (st) { + case TCP_CLOSE: + /* This is ok... continue with connect */ + break; + case TCP_ESTABLISHED: + /* Socket is already connected */ + err = -EISCONN; + goto out_unlock; + default: + err = -EINVAL; + goto out_unlock; + } + + unix_state_wlock(sk); + + if (sk->sk_state != st) { + unix_state_wunlock(sk); + unix_state_runlock(other); + sock_put(other); + goto restart; + } + + err = security_unix_stream_connect(sock, other->sk_socket, newsk); + if (err) { + unix_state_wunlock(sk); + goto out_unlock; + } + + /* The way is open! Fastly set all the necessary fields... */ + + sock_hold(sk); + unix_peer(newsk) = sk; + newsk->sk_state = TCP_ESTABLISHED; + newsk->sk_type = sk->sk_type; + newsk->sk_peercred.pid = current->tgid; + newsk->sk_peercred.uid = current->euid; + newsk->sk_peercred.gid = current->egid; + newu = unix_sk(newsk); + newsk->sk_sleep = &newu->peer_wait; + otheru = unix_sk(other); + + /* copy address information from listening to new sock*/ + if (otheru->addr) { + atomic_inc(&otheru->addr->refcnt); + newu->addr = otheru->addr; + } + if (otheru->dentry) { + newu->dentry = dget(otheru->dentry); + newu->mnt = mntget(otheru->mnt); + } + + /* Set credentials */ + sk->sk_peercred = other->sk_peercred; + + sock_hold(newsk); + unix_peer(sk) = newsk; + sock->state = SS_CONNECTED; + sk->sk_state = TCP_ESTABLISHED; + + unix_state_wunlock(sk); + + /* take ten and and send info to listening sock */ + spin_lock(&other->sk_receive_queue.lock); + __skb_queue_tail(&other->sk_receive_queue, skb); + /* Undo artificially decreased inflight after embrion + * is installed to listening socket. */ + atomic_inc(&newu->inflight); + spin_unlock(&other->sk_receive_queue.lock); + unix_state_runlock(other); + other->sk_data_ready(other, 0); + sock_put(other); + return 0; + +out_unlock: + if (other) + unix_state_runlock(other); + +out: + if (skb) + kfree_skb(skb); + if (newsk) + unix_release_sock(newsk, 0); + if (other) + sock_put(other); + return err; +} + +static int unix_socketpair(struct socket *socka, struct socket *sockb) +{ + struct sock *ska=socka->sk, *skb = sockb->sk; + + /* Join our sockets back to back */ + sock_hold(ska); + sock_hold(skb); + unix_peer(ska)=skb; + unix_peer(skb)=ska; + ska->sk_peercred.pid = skb->sk_peercred.pid = current->tgid; + ska->sk_peercred.uid = skb->sk_peercred.uid = current->euid; + ska->sk_peercred.gid = skb->sk_peercred.gid = current->egid; + + if (ska->sk_type != SOCK_DGRAM) { + ska->sk_state = TCP_ESTABLISHED; + skb->sk_state = TCP_ESTABLISHED; + socka->state = SS_CONNECTED; + sockb->state = SS_CONNECTED; + } + return 0; +} + +static int unix_accept(struct socket *sock, struct socket *newsock, int flags) +{ + struct sock *sk = sock->sk; + struct sock *tsk; + struct sk_buff *skb; + int err; + + err = -EOPNOTSUPP; + if (sock->type!=SOCK_STREAM && sock->type!=SOCK_SEQPACKET) |