| /* |
| * 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 1.129 2002-01-12 08:00:30 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. |
| * |
| * |
| * 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=NODEV, 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/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 <net/scm.h> |
| #include <linux/init.h> |
| #include <linux/poll.h> |
| #include <linux/smp_lock.h> |
| |
| #include <asm/checksum.h> |
| |
| int sysctl_unix_max_dgram_qlen = 10; |
| |
| unix_socket *unix_socket_table[UNIX_HASH_SIZE+1]; |
| rwlock_t unix_table_lock = RW_LOCK_UNLOCKED; |
| static atomic_t unix_nr_socks = ATOMIC_INIT(0); |
| |
| #define unix_sockets_unbound (unix_socket_table[UNIX_HASH_SIZE]) |
| |
| #define UNIX_ABSTRACT(sk) ((sk)->protinfo.af_unix.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) ((sk)->pair) |
| |
| static inline int unix_our_peer(unix_socket *sk, unix_socket *osk) |
| { |
| return unix_peer(osk) == sk; |
| } |
| |
| static inline int unix_may_send(unix_socket *sk, unix_socket *osk) |
| { |
| return (unix_peer(osk) == NULL || unix_our_peer(sk, osk)); |
| } |
| |
| static inline unix_socket * unix_peer_get(unix_socket *s) |
| { |
| unix_socket *peer; |
| |
| unix_state_rlock(s); |
| peer = unix_peer(s); |
| if (peer) |
| sock_hold(peer); |
| unix_state_runlock(s); |
| return peer; |
| } |
| |
| extern 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. |
| */ |
| if (len > sizeof(*sunaddr)) |
| len = sizeof(*sunaddr); |
| ((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(unix_socket *sk) |
| { |
| unix_socket **list = sk->protinfo.af_unix.list; |
| if (list) { |
| if (sk->next) |
| sk->next->prev = sk->prev; |
| if (sk->prev) |
| sk->prev->next = sk->next; |
| if (*list == sk) |
| *list = sk->next; |
| sk->protinfo.af_unix.list = NULL; |
| sk->prev = NULL; |
| sk->next = NULL; |
| __sock_put(sk); |
| } |
| } |
| |
| static void __unix_insert_socket(unix_socket **list, unix_socket *sk) |
| { |
| BUG_TRAP(sk->protinfo.af_unix.list==NULL); |
| |
| sk->protinfo.af_unix.list = list; |
| sk->prev = NULL; |
| sk->next = *list; |
| if (*list) |
| (*list)->prev = sk; |
| *list=sk; |
| sock_hold(sk); |
| } |
| |
| static inline void unix_remove_socket(unix_socket *sk) |
| { |
| write_lock(&unix_table_lock); |
| __unix_remove_socket(sk); |
| write_unlock(&unix_table_lock); |
| } |
| |
| static inline void unix_insert_socket(unix_socket **list, unix_socket *sk) |
| { |
| write_lock(&unix_table_lock); |
| __unix_insert_socket(list, sk); |
| write_unlock(&unix_table_lock); |
| } |
| |
| static unix_socket *__unix_find_socket_byname(struct sockaddr_un *sunname, |
| int len, int type, unsigned hash) |
| { |
| unix_socket *s; |
| |
| for (s=unix_socket_table[hash^type]; s; s=s->next) { |
| if(s->protinfo.af_unix.addr->len==len && |
| memcmp(s->protinfo.af_unix.addr->name, sunname, len) == 0) |
| return s; |
| } |
| return NULL; |
| } |
| |
| static inline unix_socket * |
| unix_find_socket_byname(struct sockaddr_un *sunname, |
| int len, int type, unsigned hash) |
| { |
| unix_socket *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 unix_socket *unix_find_socket_byinode(struct inode *i) |
| { |
| unix_socket *s; |
| |
| read_lock(&unix_table_lock); |
| for (s=unix_socket_table[i->i_ino & (UNIX_HASH_SIZE-1)]; s; s=s->next) |
| { |
| struct dentry *dentry = s->protinfo.af_unix.dentry; |
| |
| if(dentry && dentry->d_inode == i) |
| { |
| sock_hold(s); |
| break; |
| } |
| } |
| read_unlock(&unix_table_lock); |
| return s; |
| } |
| |
| static inline int unix_writable(struct sock *sk) |
| { |
| return ((atomic_read(&sk->wmem_alloc)<<2) <= sk->sndbuf); |
| } |
| |
| static void unix_write_space(struct sock *sk) |
| { |
| read_lock(&sk->callback_lock); |
| if (unix_writable(sk)) { |
| if (sk->sleep && waitqueue_active(sk->sleep)) |
| wake_up_interruptible(sk->sleep); |
| sk_wake_async(sk, 2, POLL_OUT); |
| } |
| read_unlock(&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->receive_queue)) { |
| skb_queue_purge(&sk->receive_queue); |
| wake_up_interruptible_all(&sk->protinfo.af_unix.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 (!other->dead && unix_peer(other) == sk) { |
| other->err = ECONNRESET; |
| other->error_report(other); |
| } |
| } |
| } |
| |
| static void unix_sock_destructor(struct sock *sk) |
| { |
| skb_queue_purge(&sk->receive_queue); |
| |
| BUG_TRAP(atomic_read(&sk->wmem_alloc) == 0); |
| BUG_TRAP(sk->protinfo.af_unix.list==NULL); |
| BUG_TRAP(sk->socket==NULL); |
| if (sk->dead==0) { |
| printk("Attempt to release alive unix socket: %p\n", sk); |
| return; |
| } |
| |
| if (sk->protinfo.af_unix.addr) |
| unix_release_addr(sk->protinfo.af_unix.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 |
| MOD_DEC_USE_COUNT; |
| } |
| |
| static int unix_release_sock (unix_socket *sk, int embrion) |
| { |
| struct dentry *dentry; |
| struct vfsmount *mnt; |
| unix_socket *skpair; |
| struct sk_buff *skb; |
| int state; |
| |
| unix_remove_socket(sk); |
| |
| /* Clear state */ |
| unix_state_wlock(sk); |
| sock_orphan(sk); |
| sk->shutdown = SHUTDOWN_MASK; |
| dentry = sk->protinfo.af_unix.dentry; |
| sk->protinfo.af_unix.dentry=NULL; |
| mnt = sk->protinfo.af_unix.mnt; |
| sk->protinfo.af_unix.mnt=NULL; |
| state = sk->state; |
| sk->state = TCP_CLOSE; |
| unix_state_wunlock(sk); |
| |
| wake_up_interruptible_all(&sk->protinfo.af_unix.peer_wait); |
| |
| skpair=unix_peer(sk); |
| |
| if (skpair!=NULL) { |
| if (sk->type==SOCK_STREAM) { |
| unix_state_wlock(skpair); |
| skpair->shutdown=SHUTDOWN_MASK; /* No more writes*/ |
| if (!skb_queue_empty(&sk->receive_queue) || embrion) |
| skpair->err = ECONNRESET; |
| unix_state_wunlock(skpair); |
| skpair->state_change(skpair); |
| read_lock(&skpair->callback_lock); |
| sk_wake_async(skpair,1,POLL_HUP); |
| read_unlock(&skpair->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->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; |
| |
| err = -EOPNOTSUPP; |
| if (sock->type!=SOCK_STREAM) |
| goto out; /* Only stream sockets accept */ |
| err = -EINVAL; |
| if (!sk->protinfo.af_unix.addr) |
| goto out; /* No listens on an unbound socket */ |
| unix_state_wlock(sk); |
| if (sk->state != TCP_CLOSE && sk->state != TCP_LISTEN) |
| goto out_unlock; |
| if (backlog > sk->max_ack_backlog) |
| wake_up_interruptible_all(&sk->protinfo.af_unix.peer_wait); |
| sk->max_ack_backlog=backlog; |
| sk->state=TCP_LISTEN; |
| /* set credentials so connect can copy them */ |
| sk->peercred.pid = current->pid; |
| sk->peercred.uid = current->euid; |
| sk->peercred.gid = current->egid; |
| err = 0; |
| |
| out_unlock: |
| unix_state_wunlock(sk); |
| out: |
| return err; |
| } |
| |
| extern struct proto_ops unix_stream_ops; |
| extern struct proto_ops unix_dgram_ops; |
| |
| static struct sock * unix_create1(struct socket *sock) |
| { |
| struct sock *sk; |
| |
| if (atomic_read(&unix_nr_socks) >= 2*files_stat.max_files) |
| return NULL; |
| |
| MOD_INC_USE_COUNT; |
| sk = sk_alloc(PF_UNIX, GFP_KERNEL, 1); |
| if (!sk) { |
| MOD_DEC_USE_COUNT; |
| return NULL; |
| } |
| |
| atomic_inc(&unix_nr_socks); |
| |
| sock_init_data(sock,sk); |
| |
| sk->write_space = unix_write_space; |
| |
| sk->max_ack_backlog = sysctl_unix_max_dgram_qlen; |
| sk->destruct = unix_sock_destructor; |
| sk->protinfo.af_unix.dentry=NULL; |
| sk->protinfo.af_unix.mnt=NULL; |
| sk->protinfo.af_unix.lock = RW_LOCK_UNLOCKED; |
| atomic_set(&sk->protinfo.af_unix.inflight, sock ? 0 : -1); |
| init_MUTEX(&sk->protinfo.af_unix.readsem);/* single task reading lock */ |
| init_waitqueue_head(&sk->protinfo.af_unix.peer_wait); |
| sk->protinfo.af_unix.list=NULL; |
| unix_insert_socket(&unix_sockets_unbound, sk); |
| |
| 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; |
| default: |
| return -ESOCKTNOSUPPORT; |
| } |
| |
| return unix_create1(sock) ? 0 : -ENOMEM; |
| } |
| |
| static int unix_release(struct socket *sock) |
| { |
| unix_socket *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; |
| static u32 ordernum = 1; |
| struct unix_address * addr; |
| int err; |
| |
| down(&sk->protinfo.af_unix.readsem); |
| |
| err = 0; |
| if (sk->protinfo.af_unix.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->type; |
| |
| __unix_remove_socket(sk); |
| sk->protinfo.af_unix.addr = addr; |
| __unix_insert_socket(&unix_socket_table[addr->hash], sk); |
| write_unlock(&unix_table_lock); |
| err = 0; |
| |
| out: |
| up(&sk->protinfo.af_unix.readsem); |
| return err; |
| } |
| |
| static unix_socket *unix_find_other(struct sockaddr_un *sunname, int len, |
| int type, unsigned hash, int *error) |
| { |
| unix_socket *u; |
| struct nameidata nd; |
| int err = 0; |
| |
| if (sunname->sun_path[0]) { |
| if (path_init(sunname->sun_path, |
| LOOKUP_POSITIVE|LOOKUP_FOLLOW, &nd)) |
| err = path_walk(sunname->sun_path, &nd); |
| if (err) |
| goto fail; |
| err = permission(nd.dentry->d_inode,MAY_WRITE); |
| 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; |
| |
| path_release(&nd); |
| |
| err=-EPROTOTYPE; |
| if (u->type != type) { |
| sock_put(u); |
| goto fail; |
| } |
| } else { |
| err = -ECONNREFUSED; |
| u=unix_find_socket_byname(sunname, len, type, hash); |
| if (!u) |
| 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 sockaddr_un *sunaddr=(struct sockaddr_un *)uaddr; |
| struct dentry * dentry = NULL; |
| struct nameidata nd; |
| int err; |
| unsigned hash; |
| struct unix_address *addr; |
| unix_socket **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(&sk->protinfo.af_unix.readsem); |
| |
| err = -EINVAL; |
| if (sk->protinfo.af_unix.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->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. |
| */ |
| if (path_init(sunaddr->sun_path, LOOKUP_PARENT, &nd)) |
| err = path_walk(sunaddr->sun_path, &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->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->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)]; |
| sk->protinfo.af_unix.dentry = nd.dentry; |
| sk->protinfo.af_unix.mnt = nd.mnt; |
| } |
| |
| err = 0; |
| __unix_remove_socket(sk); |
| sk->protinfo.af_unix.addr = addr; |
| __unix_insert_socket(list, sk); |
| |
| out_unlock: |
| write_unlock(&unix_table_lock); |
| out_up: |
| up(&sk->protinfo.af_unix.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 (sock->passcred && !sk->protinfo.af_unix.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; |
| } 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(unix_socket *other, long timeo) |
| { |
| int sched; |
| DECLARE_WAITQUEUE(wait, current); |
| |
| __set_current_state(TASK_INTERRUPTIBLE); |
| add_wait_queue_exclusive(&other->protinfo.af_unix.peer_wait, &wait); |
| |
| sched = (!other->dead && |
| !(other->shutdown&RCV_SHUTDOWN) && |
| skb_queue_len(&other->receive_queue) > other->max_ack_backlog); |
| |
| unix_state_runlock(other); |
| |
| if (sched) |
| timeo = schedule_timeout(timeo); |
| |
| __set_current_state(TASK_RUNNING); |
| remove_wait_queue(&other->protinfo.af_unix.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 sock *newsk = NULL; |
| unix_socket *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 (sock->passcred && !sk->protinfo.af_unix.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->type, hash, &err); |
| if (!other) |
| goto out; |
| |
| /* Latch state of peer */ |
| unix_state_rlock(other); |
| |
| /* Apparently VFS overslept socket death. Retry. */ |
| if (other->dead) { |
| unix_state_runlock(other); |
| sock_put(other); |
| goto restart; |
| } |
| |
| err = -ECONNREFUSED; |
| if (other->state != TCP_LISTEN) |
| goto out_unlock; |
| |
| if (skb_queue_len(&other->receive_queue) > other->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->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->state != st) { |
| unix_state_wunlock(sk); |
| unix_state_runlock(other); |
| sock_put(other); |
| goto restart; |
| } |
| |
| /* The way is open! Fastly set all the necessary fields... */ |
| |
| sock_hold(sk); |
| unix_peer(newsk)=sk; |
| newsk->state=TCP_ESTABLISHED; |
| newsk->type=SOCK_STREAM; |
| newsk->peercred.pid = current->pid; |
| newsk->peercred.uid = current->euid; |
| newsk->peercred.gid = current->egid; |
| newsk->sleep = &newsk->protinfo.af_unix.peer_wait; |
| |
| /* copy address information from listening to new sock*/ |
| if (other->protinfo.af_unix.addr) |
| { |
| atomic_inc(&other->protinfo.af_unix.addr->refcnt); |
| newsk->protinfo.af_unix.addr=other->protinfo.af_unix.addr; |
| } |
| if (other->protinfo.af_unix.dentry) { |
| newsk->protinfo.af_unix.dentry=dget(other->protinfo.af_unix.dentry); |
| newsk->protinfo.af_unix.mnt=mntget(other->protinfo.af_unix.mnt); |
| } |
| |
| /* Set credentials */ |
| sk->peercred = other->peercred; |
| |
| sock_hold(newsk); |
| unix_peer(sk)=newsk; |
| sock->state=SS_CONNECTED; |
| sk->state=TCP_ESTABLISHED; |
| |
| unix_state_wunlock(sk); |
| |
| /* take ten and and send info to listening sock */ |
| spin_lock(&other->receive_queue.lock); |
| __skb_queue_tail(&other->receive_queue,skb); |
| /* Undo artificially decreased inflight after embrion |
| * is installed to listening socket. */ |
| atomic_inc(&newsk->protinfo.af_unix.inflight); |
| spin_unlock(&other->receive_queue.lock); |
| unix_state_runlock(other); |
| other->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->peercred.pid = skb->peercred.pid = current->pid; |
| ska->peercred.uid = skb->peercred.uid = current->euid; |
| ska->peercred.gid = skb->peercred.gid = current->egid; |
| |
| if (ska->type != SOCK_DGRAM) |
| { |
| ska->state=TCP_ESTABLISHED; |
| skb->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) |
| { |
| unix_socket *sk = sock->sk; |
| unix_socket *tsk; |
| struct sk_buff *skb; |
| int err; |
| |
| err = -EOPNOTSUPP; |
| if (sock->type!=SOCK_STREAM) |
| goto out; |
| |
| err = -EINVAL; |
| if (sk->state!=TCP_LISTEN) |
| goto out; |
| |
| /* If socket state is TCP_LISTEN it cannot change (for now...), |
| * so that no locks are necessary. |
| */ |
| |
| skb = skb_recv_datagram(sk, 0, flags&O_NONBLOCK, &err); |
| if (!skb) |
| goto out; |
| |
| tsk = skb->sk; |
| skb_free_datagram(sk, skb); |
| wake_up_interruptible(&sk->protinfo.af_unix.peer_wait); |
| |
| /* attach accepted sock to socket */ |
| unix_state_wlock(tsk); |
| newsock->state = SS_CONNECTED; |
| sock_graft(tsk, newsock); |
| unix_state_wunlock(tsk); |
| return 0; |
| |
| out: |
| return err; |
| } |
| |
| |
| static int unix_getname(struct socket *sock, struct sockaddr *uaddr, int *uaddr_len, int peer) |
| { |
| struct sock *sk = sock->sk; |
| struct sockaddr_un *sunaddr=(struct sockaddr_un *)uaddr; |
| int err = 0; |
| |
| if (peer) { |
| sk = unix_peer_get(sk); |
| |
| err = -ENOTCONN; |
| if (!sk) |
| goto out; |
| err = 0; |
| } else { |
| sock_hold(sk); |
| } |
| |
| unix_state_rlock(sk); |
| if (!sk->protinfo.af_unix.addr) { |
| sunaddr->sun_family = AF_UNIX; |
| sunaddr->sun_path[0] = 0; |
| *uaddr_len = sizeof(short); |
| } else { |
| struct unix_address *addr = sk->protinfo.af_unix.addr; |
| |
| *uaddr_len = addr->len; |
| memcpy(sunaddr, addr->name, *uaddr_len); |
| } |
| unix_state_runlock(sk); |
| sock_put(sk); |
| out: |
| return err; |
| } |
| |
| static void unix_detach_fds(struct scm_cookie *scm, struct sk_buff *skb) |
| { |
| int i; |
| |
| scm->fp = UNIXCB(skb).fp; |
| skb->destructor = sock_wfree; |
| UNIXCB(skb).fp = NULL; |
| |
| for (i=scm->fp->count-1; i>=0; i--) |
| unix_notinflight(scm->fp->fp[i]); |
| } |
| |
| static void unix_destruct_fds(struct sk_buff *skb) |
| { |
| struct scm_cookie scm; |
| memset(&scm, 0, sizeof(scm)); |
| unix_detach_fds(&scm, skb); |
| |
| /* Alas, it calls VFS */ |
| /* So fscking what? fput() had been SMP-safe since the last Summer */ |
| scm_destroy(&scm); |
| sock_wfree(skb); |
| } |
| |
| static void unix_attach_fds(struct scm_cookie *scm, struct sk_buff *skb) |
| { |
| int i; |
| for (i=scm->fp->count-1; i>=0; i--) |
| unix_inflight(scm->fp->fp[i]); |
| UNIXCB(skb).fp = scm->fp; |
| skb->destructor = unix_destruct_fds; |
| scm->fp = NULL; |
| } |
| |
| /* |
| * Send AF_UNIX data. |
| */ |
| |
| static int unix_dgram_sendmsg(struct socket *sock, struct msghdr *msg, int len, |
| struct scm_cookie *scm) |
| { |
| struct sock *sk = sock->sk; |
| struct sockaddr_un *sunaddr=msg->msg_name; |
| unix_socket *other = NULL; |
| int namelen = 0; /* fake GCC */ |
| int err; |
| unsigned hash; |
| struct sk_buff *skb; |
| long timeo; |
| |
| err = -EOPNOTSUPP; |
| if (msg->msg_flags&MSG_OOB) |
| goto out; |
| |
| if (msg->msg_namelen) { |
| err = unix_mkname(sunaddr, msg->msg_namelen, &hash); |
| if (err < 0) |
| goto out; |
| namelen = err; |
| } else { |
| sunaddr = NULL; |
| err = -ENOTCONN; |
| other = unix_peer_get(sk); |
| if (!other) |
| goto out; |
| } |
| |
| if (sock->passcred && !sk->protinfo.af_unix.addr && |
| (err = unix_autobind(sock)) != 0) |
| goto out; |
| |
| err = -EMSGSIZE; |
| if ((unsigned)len > sk->sndbuf - 32) |
| goto out; |
| |
| skb = sock_alloc_send_skb(sk, len, msg->msg_flags&MSG_DONTWAIT, &err); |
| if (skb==NULL) |
| goto out; |
| |
| memcpy(UNIXCREDS(skb), &scm->creds, sizeof(struct ucred)); |
| if (scm->fp) |
| unix_attach_fds(scm, skb); |
| |
| skb->h.raw = skb->data; |
| err = memcpy_fromiovec(skb_put(skb,len), msg->msg_iov, len); |
| if (err) |
| goto out_free; |
| |
| timeo = sock_sndtimeo(sk, msg->msg_flags & MSG_DONTWAIT); |
| |
| restart: |
| if (!other) { |
| err = -ECONNRESET; |
| if (sunaddr == NULL) |
| goto out_free; |
| |
| other = unix_find_other(sunaddr, namelen, sk->type, hash, &err); |
| if (other==NULL) |
| goto out_free; |
| } |
| |
| unix_state_rlock(other); |
| err = -EPERM; |
| if (!unix_may_send(sk, other)) |
| goto out_unlock; |
| |
| if (other->dead) { |
| /* |
| * Check with 1003.1g - what should |
| * datagram error |
| */ |
| unix_state_runlock(other); |
| sock_put(other); |
| |
| err = 0; |
| unix_state_wlock(sk); |
| if (unix_peer(sk) == other) { |
| unix_peer(sk)=NULL; |
| unix_state_wunlock(sk); |
| |
| unix_dgram_disconnected(sk, other); |
| sock_put(other); |
| err = -ECONNREFUSED; |
| } else { |
| unix_state_wunlock(sk); |
| } |
| |
| other = NULL; |
| if (err) |
| goto out_free; |
| goto restart; |
| } |
| |
| err = -EPIPE; |
| if (other->shutdown&RCV_SHUTDOWN) |
| goto out_unlock; |
| |
| if (unix_peer(other) != sk && |
| skb_queue_len(&other->receive_queue) > other->max_ack_backlog) { |
| if (!timeo) { |
| err = -EAGAIN; |
| goto out_unlock; |
| } |
| |
| timeo = unix_wait_for_peer(other, timeo); |
| |
| err = sock_intr_errno(timeo); |
| if (signal_pending(current)) |
| goto out_free; |
| |
| goto restart; |
| } |
| |
| skb_queue_tail(&other->receive_queue, skb); |
| unix_state_runlock(other); |
| other->data_ready(other, len); |
| sock_put(other); |
| return len; |
| |
| out_unlock: |
| unix_state_runlock(other); |
| out_free: |
| kfree_skb(skb); |
| out: |
| if (other) |
| sock_put(other); |
| return err; |
| } |
| |
| |
| static int unix_stream_sendmsg(struct socket *sock, struct msghdr *msg, int len, |
| struct scm_cookie *scm) |
| { |
| struct sock *sk = sock->sk; |
| unix_socket *other = NULL; |
| struct sockaddr_un *sunaddr=msg->msg_name; |
| int err,size; |
| struct sk_buff *skb; |
| int sent=0; |
| |
| err = -EOPNOTSUPP; |
| if (msg->msg_flags&MSG_OOB) |
| goto out_err; |
| |
| if (msg->msg_namelen) { |
| err = (sk->state==TCP_ESTABLISHED ? -EISCONN : -EOPNOTSUPP); |
| goto out_err; |
| } else { |
| sunaddr = NULL; |
| err = -ENOTCONN; |
| other = unix_peer_get(sk); |
| if (!other) |
| goto out_err; |
| } |
| |
| if (sk->shutdown&SEND_SHUTDOWN) |
| goto pipe_err; |
| |
| while(sent < len) |
| { |
| /* |
| * Optimisation for the fact that under 0.01% of X messages typically |
| * need breaking up. |
| */ |
| |
| size=len-sent; |
| |
| /* Keep two messages in the pipe so it schedules better */ |
| if (size > sk->sndbuf/2 - 64) |
| size = sk->sndbuf/2 - 64; |
| |
| if (size > SKB_MAX_ALLOC) |
| size = SKB_MAX_ALLOC; |
| |
| /* |
| * Grab a buffer |
| */ |
| |
| skb=sock_alloc_send_skb(sk,size,msg->msg_flags&MSG_DONTWAIT, &err); |
| |
| if (skb==NULL) |
| goto out_err; |
| |
| /* |
| * If you pass two values to the sock_alloc_send_skb |
| * it tries to grab the large buffer with GFP_NOFS |
| * (which can fail easily), and if it fails grab the |
| * fallback size buffer which is under a page and will |
| * succeed. [Alan] |
| */ |
| size = min_t(int, size, skb_tailroom(skb)); |
| |
| memcpy(UNIXCREDS(skb), &scm->creds, sizeof(struct ucred)); |
| if (scm->fp) |
| unix_attach_fds(scm, skb); |
| |
| if ((err = memcpy_fromiovec(skb_put(skb,size), msg->msg_iov, size)) != 0) { |
| kfree_skb(skb); |
| goto out_err; |
| } |
| |
| unix_state_rlock(other); |
| |
| if (other->dead || (other->shutdown & RCV_SHUTDOWN)) |
| goto pipe_err_free; |
| |
| skb_queue_tail(&other->receive_queue, skb); |
| unix_state_runlock(other); |
| other->data_ready(other, size); |
| sent+=size; |
| } |
| sock_put(other); |
| return sent; |
| |
| pipe_err_free: |
| unix_state_runlock(other); |
| kfree_skb(skb); |
| pipe_err: |
| if (sent==0 && !(msg->msg_flags&MSG_NOSIGNAL)) |
| send_sig(SIGPIPE,current,0); |
| err = -EPIPE; |
| out_err: |
| if (other) |
| sock_put(other); |
| return sent ? : err; |
| } |
| |
| static void unix_copy_addr(struct msghdr *msg, struct sock *sk) |
| { |
| msg->msg_namelen = sizeof(short); |
| if (sk->protinfo.af_unix.addr) { |
| msg->msg_namelen=sk->protinfo.af_unix.addr->len; |
| memcpy(msg->msg_name, |
| sk->protinfo.af_unix.addr->name, |
| sk->protinfo.af_unix.addr->len); |
| } |
| } |
| |
| static int unix_dgram_recvmsg(struct socket *sock, struct msghdr *msg, int size, |
| int flags, struct scm_cookie *scm) |
| { |
| struct sock *sk = sock->sk; |
| int noblock = flags & MSG_DONTWAIT; |
| struct sk_buff *skb; |
| int err; |
| |
| err = -EOPNOTSUPP; |
| if (flags&MSG_OOB) |
| goto out; |
| |
| msg->msg_namelen = 0; |
| |
| skb = skb_recv_datagram(sk, flags, noblock, &err); |
| if (!skb) |
| goto out; |
| |
| wake_up_interruptible(&sk->protinfo.af_unix.peer_wait); |
| |
| if (msg->msg_name) |
| unix_copy_addr(msg, skb->sk); |
| |
| if (size > skb->len) |
| size = skb->len; |
| else if (size < skb->len) |
| msg->msg_flags |= MSG_TRUNC; |
| |
| err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, size); |
| if (err) |
| goto out_free; |
| |
| scm->creds = *UNIXCREDS(skb); |
| |
| if (!(flags & MSG_PEEK)) |
| { |
| if (UNIXCB(skb).fp) |
| unix_detach_fds(scm, skb); |
| } |
| else |
| { |
| /* It is questionable: on PEEK we could: |
| - do not return fds - good, but too simple 8) |
| - return fds, and do not return them on read (old strategy, |
| apparently wrong) |
| - clone fds (I choosed it for now, it is the most universal |
| solution) |
| |
| POSIX 1003.1g does not actually define this clearly |
| at all. POSIX 1003.1g doesn't define a lot of things |
| clearly however! |
| |
| */ |
| if (UNIXCB(skb).fp) |
| scm->fp = scm_fp_dup(UNIXCB(skb).fp); |
| } |
| err = size; |
| |
| out_free: |
| skb_free_datagram(sk,skb); |
| out: |
| return err; |
| } |
| |
| /* |
| * Sleep until data has arrive. But check for races.. |
| */ |
| |
| static long unix_stream_data_wait(unix_socket * sk, long timeo) |
| { |
| DECLARE_WAITQUEUE(wait, current); |
| |
| unix_state_rlock(sk); |
| |
| add_wait_queue(sk->sleep, &wait); |
| |
| for (;;) { |
| set_current_state(TASK_INTERRUPTIBLE); |
| |
| if (skb_queue_len(&sk->receive_queue) || |
| sk->err || |
| (sk->shutdown & RCV_SHUTDOWN) || |
| signal_pending(current) || |
| !timeo) |
| break; |
| |
| set_bit(SOCK_ASYNC_WAITDATA, &sk->socket->flags); |
| unix_state_runlock(sk); |
| timeo = schedule_timeout(timeo); |
| unix_state_rlock(sk); |
| clear_bit(SOCK_ASYNC_WAITDATA, &sk->socket->flags); |
| } |
| |
| __set_current_state(TASK_RUNNING); |
| remove_wait_queue(sk->sleep, &wait); |
| unix_state_runlock(sk); |
| return timeo; |
| } |
| |
| |
| |
| static int unix_stream_recvmsg(struct socket *sock, struct msghdr *msg, int size, |
| int flags, struct scm_cookie *scm) |
| { |
| struct sock *sk = sock->sk; |
| struct sockaddr_un *sunaddr=msg->msg_name; |
| int copied = 0; |
| int check_creds = 0; |
| int target; |
| int err = 0; |
| long timeo; |
| |
| err = -EINVAL; |
| if (sk->state != TCP_ESTABLISHED) |
| goto out; |
| |
| err = -EOPNOTSUPP; |
| if (flags&MSG_OOB) |
| goto out; |
| |
| target = sock_rcvlowat(sk, flags&MSG_WAITALL, size); |
| timeo = sock_rcvtimeo(sk, flags&MSG_DONTWAIT); |
| |
| msg->msg_namelen = 0; |
| |
| /* Lock the socket to prevent queue disordering |
| * while sleeps in memcpy_tomsg |
| */ |
| |
| down(&sk->protinfo.af_unix.readsem); |
| |
| do |
| { |
| int chunk; |
| struct sk_buff *skb; |
| |
| skb=skb_dequeue(&sk->receive_queue); |
| if (skb==NULL) |
| { |
| if (copied >= target) |
| break; |
| |
| /* |
| * POSIX 1003.1g mandates this order. |
| */ |
| |
| if ((err = sock_error(sk)) != 0) |
| break; |
| if (sk->shutdown & RCV_SHUTDOWN) |
| break; |
| err = -EAGAIN; |
| if (!timeo) |
| break; |
| up(&sk->protinfo.af_unix.readsem); |
| |
| timeo = unix_stream_data_wait(sk, timeo); |
| |
| if (signal_pending(current)) { |
| err = sock_intr_errno(timeo); |
| goto out; |
| } |
| down(&sk->protinfo.af_unix.readsem); |
| continue; |
| } |
| |
| if (check_creds) { |
| /* Never glue messages from different writers */ |
| if (memcmp(UNIXCREDS(skb), &scm->creds, sizeof(scm->creds)) != 0) { |
| skb_queue_head(&sk->receive_queue, skb); |
| break; |
| } |
| } else { |
| /* Copy credentials */ |
| scm->creds = *UNIXCREDS(skb); |
| check_creds = 1; |
| } |
| |
| /* Copy address just once */ |
| if (sunaddr) |
| { |
| unix_copy_addr(msg, skb->sk); |
| sunaddr = NULL; |
| } |
| |
| chunk = min_t(unsigned int, skb->len, size); |
| if (memcpy_toiovec(msg->msg_iov, skb->data, chunk)) { |
| skb_queue_head(&sk->receive_queue, skb); |
| if (copied == 0) |
| copied = -EFAULT; |
| break; |
| } |
| copied += chunk; |
| size -= chunk; |
| |
| /* Mark read part of skb as used */ |
| if (!(flags & MSG_PEEK)) |
| { |
| skb_pull(skb, chunk); |
| |
| if (UNIXCB(skb).fp) |
| unix_detach_fds(scm, skb); |
| |
| /* put the skb back if we didn't use it up.. */ |
| if (skb->len) |
| { |
| skb_queue_head(&sk->receive_queue, skb); |
| break; |
| } |
| |
| kfree_skb(skb); |
| |
| if (scm->fp) |
| break; |
| } |
| else |
| { |
| /* It is questionable, see note in unix_dgram_recvmsg. |
| */ |
| if (UNIXCB(skb).fp) |
| scm->fp = scm_fp_dup(UNIXCB(skb).fp); |
| |
| /* put message back and return */ |
| skb_queue_head(&sk->receive_queue, skb); |
| break; |
| } |
| } while (size); |
| |
| up(&sk->protinfo.af_unix.readsem); |
| out: |
| return copied ? : err; |
| } |
| |
| static int unix_shutdown(struct socket *sock, int mode) |
| { |
| struct sock *sk = sock->sk; |
| unix_socket *other; |
| |
| mode = (mode+1)&(RCV_SHUTDOWN|SEND_SHUTDOWN); |
| |
| if (mode) { |
| unix_state_wlock(sk); |
| sk->shutdown |= mode; |
| other=unix_peer(sk); |
| if (other) |
| sock_hold(other); |
| unix_state_wunlock(sk); |
| sk->state_change(sk); |
| |
| if (other && sk->type == SOCK_STREAM) { |
| int peer_mode = 0; |
| |
| if (mode&RCV_SHUTDOWN) |
| peer_mode |= SEND_SHUTDOWN; |
| if (mode&SEND_SHUTDOWN) |
| peer_mode |= RCV_SHUTDOWN; |
| unix_state_wlock(other); |
| other->shutdown |= peer_mode; |
| unix_state_wunlock(other); |
| other->state_change(other); |
| read_lock(&other->callback_lock); |
| if (peer_mode == SHUTDOWN_MASK) |
| sk_wake_async(other,1,POLL_HUP); |
| else if (peer_mode & RCV_SHUTDOWN) |
| sk_wake_async(other,1,POLL_IN); |
| read_unlock(&other->callback_lock); |
| } |
| if (other) |
| sock_put(other); |
| } |
| return 0; |
| } |
| |
| static int unix_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg) |
| { |
| struct sock *sk = sock->sk; |
| long amount=0; |
| int err; |
| |
| switch(cmd) |
| { |
| case SIOCOUTQ: |
| amount = atomic_read(&sk->wmem_alloc); |
| err = put_user(amount, (int *)arg); |
| break; |
| case SIOCINQ: |
| { |
| struct sk_buff *skb; |
| if (sk->state==TCP_LISTEN) { |
| err = -EINVAL; |
| break; |
| } |
| |
| spin_lock(&sk->receive_queue.lock); |
| if((skb=skb_peek(&sk->receive_queue))!=NULL) |
| amount=skb->len; |
| spin_unlock(&sk->receive_queue.lock); |
| err = put_user(amount, (int *)arg); |
| break; |
| } |
| |
| default: |
| err = dev_ioctl(cmd, (void *)arg); |
| break; |
| } |
| return err; |
| } |
| |
| static unsigned int unix_poll(struct file * file, struct socket *sock, poll_table *wait) |
| { |
| struct sock *sk = sock->sk; |
| unsigned int mask; |
| |
| poll_wait(file, sk->sleep, wait); |
| mask = 0; |
| |
| /* exceptional events? */ |
| if (sk->err) |
| mask |= POLLERR; |
| if (sk->shutdown == SHUTDOWN_MASK) |
| mask |= POLLHUP; |
| |
| /* readable? */ |
| if (!skb_queue_empty(&sk->receive_queue) || (sk->shutdown&RCV_SHUTDOWN)) |
| mask |= POLLIN | POLLRDNORM; |
| |
| /* Connection-based need to check for termination and startup */ |
| if (sk->type == SOCK_STREAM && sk->state==TCP_CLOSE) |
| mask |= POLLHUP; |
| |
| /* |
| * we set writable also when the other side has shut down the |
| * connection. This prevents stuck sockets. |
| */ |
| if (unix_writable(sk)) |
| mask |= POLLOUT | POLLWRNORM | POLLWRBAND; |
| |
| return mask; |
| } |
| |
| |
| #ifdef CONFIG_PROC_FS |
| static int unix_read_proc(char *buffer, char **start, off_t offset, |
| int length, int *eof, void *data) |
| { |
| off_t pos=0; |
| off_t begin=0; |
| int len=0; |
| int i; |
| unix_socket *s; |
| |
| len+= sprintf(buffer,"Num RefCount Protocol Flags Type St " |
| "Inode Path\n"); |
| |
| read_lock(&unix_table_lock); |
| forall_unix_sockets (i,s) |
| { |
| unix_state_rlock(s); |
| |
| len+=sprintf(buffer+len,"%p: %08X %08X %08X %04X %02X %5ld", |
| s, |
| atomic_read(&s->refcnt), |
| 0, |
| s->state == TCP_LISTEN ? __SO_ACCEPTCON : 0, |
| s->type, |
| s->socket ? |
| (s->state == TCP_ESTABLISHED ? SS_CONNECTED : SS_UNCONNECTED) : |
| (s->state == TCP_ESTABLISHED ? SS_CONNECTING : SS_DISCONNECTING), |
| sock_i_ino(s)); |
| |
| if (s->protinfo.af_unix.addr) |
| { |
| buffer[len++] = ' '; |
| memcpy(buffer+len, s->protinfo.af_unix.addr->name->sun_path, |
| s->protinfo.af_unix.addr->len-sizeof(short)); |
| if (!UNIX_ABSTRACT(s)) |
| len--; |
| else |
| buffer[len] = '@'; |
| len += s->protinfo.af_unix.addr->len - sizeof(short); |
| } |
| unix_state_runlock(s); |
| |
| buffer[len++]='\n'; |
| |
| pos = begin + len; |
| if(pos<offset) |
| { |
| len=0; |
| begin=pos; |
| } |
| if(pos>offset+length) |
| goto done; |
| } |
| *eof = 1; |
| done: |
| read_unlock(&unix_table_lock); |
| *start=buffer+(offset-begin); |
| len-=(offset-begin); |
| if(len>length) |
| len=length; |
| if (len < 0) |
| len = 0; |
| return len; |
| } |
| #endif |
| |
| struct proto_ops unix_stream_ops = { |
| family: PF_UNIX, |
| |
| 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, |
| }; |
| |
| struct proto_ops unix_dgram_ops = { |
| family: PF_UNIX, |
| |
| 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, |
| }; |
| |
| struct net_proto_family unix_family_ops = { |
| family: PF_UNIX, |
| create: unix_create |
| }; |
| |
| #ifdef CONFIG_SYSCTL |
| extern void unix_sysctl_register(void); |
| extern void unix_sysctl_unregister(void); |
| #else |
| static inline void unix_sysctl_register(void) {} |
| static inline void unix_sysctl_unregister(void) {} |
| #endif |
| |
| static char banner[] __initdata = KERN_INFO "NET4: Unix domain sockets 1.0/SMP for Linux NET4.0.\n"; |
| |
| static int __init af_unix_init(void) |
| { |
| struct sk_buff *dummy_skb; |
| |
| printk(banner); |
| if (sizeof(struct unix_skb_parms) > sizeof(dummy_skb->cb)) |
| { |
| printk(KERN_CRIT "unix_proto_init: panic\n"); |
| return -1; |
| } |
| sock_register(&unix_family_ops); |
| #ifdef CONFIG_PROC_FS |
| create_proc_read_entry("net/unix", 0, 0, unix_read_proc, NULL); |
| #endif |
| unix_sysctl_register(); |
| return 0; |
| } |
| |
| static void __exit af_unix_exit(void) |
| { |
| sock_unregister(PF_UNIX); |
| unix_sysctl_unregister(); |
| remove_proc_entry("net/unix", 0); |
| } |
| |
| module_init(af_unix_init); |
| module_exit(af_unix_exit); |
| |
| /* |
| * Local variables: |
| * compile-command: "gcc -g -D__KERNEL__ -Wall -O6 -I/usr/src/linux/include -c af_unix.c" |
| * End: |
| */ |