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[/] [or1k_old/] [trunk/] [uclinux/] [uClinux-2.0.x/] [net/] [unix/] [af_unix.c] - Blame information for rev 1782

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/*
 * NET3:        Implementation of BSD Unix domain sockets.
 *
 * Authors:     Alan Cox, <alan@cymru.net>
 *
 *              Currently this contains all but the file descriptor passing code.
 *              Before that goes in the odd bugs in the iovec handlers need
 *              fixing, and this bit testing. BSD fd passing is not a trivial part
 *              of the exercise it turns out. Anyone like writing garbage collectors.
 *
 *              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.
 *
 * 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        :       Shutdown() bug
 *
 * 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.
 */
 
#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/socket.h>
#include <linux/sockios.h>
#include <linux/net.h>
#include <linux/in.h>
#include <linux/fs.h>
#include <linux/malloc.h>
#include <asm/segment.h>
#include <linux/skbuff.h>
#include <linux/netdevice.h>
#include <net/sock.h>
#include <net/tcp.h>
#include <net/af_unix.h>
#include <linux/proc_fs.h>
 
unix_socket *unix_socket_list=NULL;
 
#define min(a,b)        (((a)<(b))?(a):(b))
 
/*
 *      Make sure the unix name is null-terminated.
 */
 
static inline void unix_mkname(struct sockaddr_un * sunaddr, unsigned long len)
{
        if (len >= sizeof(*sunaddr))
                len = sizeof(*sunaddr)-1;
        ((char *)sunaddr)[len]=0;
}
 
/*
 *      Note: Sockets may not be removed _during_ an interrupt or net_bh
 *      handler using this technique. They can be added although we do not
 *      use this facility.
 */
 
static void unix_remove_socket(unix_socket *sk)
{
        unix_socket **s;
 
        cli();
        s=&unix_socket_list;
 
        while(*s!=NULL)
        {
                if(*s==sk)
                {
                        *s=sk->next;
                        sti();
                        return;
                }
                s=&((*s)->next);
        }
        sti();
}
 
static void unix_insert_socket(unix_socket *sk)
{
        cli();
        sk->next=unix_socket_list;
        unix_socket_list=sk;
        sti();
}
 
static unix_socket *unix_find_socket(struct inode *i)
{
        unix_socket *s;
        cli();
        s=unix_socket_list;
        while(s)
        {
                if(s->protinfo.af_unix.inode==i)
                {
                        sti();
                        return(s);
                }
                s=s->next;
        }
        sti();
        return(NULL);
}
 
/*
 *      Delete a unix socket. We have to allow for deferring this on a timer.
 */
 
static void unix_destroy_timer(unsigned long data)
{
        unix_socket *sk=(unix_socket *)data;
        if(sk->protinfo.af_unix.locks==0 && sk->wmem_alloc==0)
        {
                if(sk->protinfo.af_unix.name)
                        kfree(sk->protinfo.af_unix.name);
                sk_free(sk);
                return;
        }
 
        /*
         *      Retry;
         */
 
        sk->timer.expires=jiffies+10*HZ;        /* No real hurry try it every 10 seconds or so */
        add_timer(&sk->timer);
}
 
 
static void unix_delayed_delete(unix_socket *sk)
{
        sk->timer.data=(unsigned long)sk;
        sk->timer.expires=jiffies+HZ;           /* Normally 1 second after will clean up. After that we try every 10 */
        sk->timer.function=unix_destroy_timer;
        add_timer(&sk->timer);
}
 
static void unix_destroy_socket(unix_socket *sk)
{
        struct sk_buff *skb;
 
        unix_remove_socket(sk);
 
        while((skb=skb_dequeue(&sk->receive_queue))!=NULL)
        {
                if(sk->state==TCP_LISTEN)
                {
                        unix_socket *osk=skb->sk;
                        osk->state=TCP_CLOSE;
                        kfree_skb(skb, FREE_WRITE);     /* Now surplus - free the skb first before the socket */
                        osk->state_change(osk);         /* So the connect wakes and cleans up (if any) */
                        /* osk will be destroyed when it gets to close or the timer fires */
                }
                else
                {
                        /* passed fds are erased in the kfree_skb hook */
                        kfree_skb(skb,FREE_WRITE);
                }
        }
 
        if(sk->protinfo.af_unix.inode!=NULL)
        {
                iput(sk->protinfo.af_unix.inode);
                sk->protinfo.af_unix.inode=NULL;
        }
 
        if(--sk->protinfo.af_unix.locks==0 && sk->wmem_alloc==0)
        {
                if(sk->protinfo.af_unix.name)
                        kfree(sk->protinfo.af_unix.name);
                sk_free(sk);
        }
        else
        {
                sk->dead=1;
                unix_delayed_delete(sk);        /* Try every so often until buffers are all freed */
        }
}
 
/*
 *      Fixme: We need async I/O on AF_UNIX doing next.
 */
 
static int unix_fcntl(struct socket *sock, unsigned int cmd, unsigned long arg)
{
        return -EINVAL;
}
 
/*
 *      Yes socket options work with the new unix domain socketry!!!!!!!
 */
 
static int unix_setsockopt(struct socket *sock, int level, int optname, char *optval, int optlen)
{
        unix_socket *sk=sock->data;
        if(level!=SOL_SOCKET)
                return -EOPNOTSUPP;
        return sock_setsockopt(sk,level,optname,optval,optlen);
}
 
static int unix_getsockopt(struct socket *sock, int level, int optname, char *optval, int *optlen)
{
        unix_socket *sk=sock->data;
        if(level!=SOL_SOCKET)
                return -EOPNOTSUPP;
        return sock_getsockopt(sk,level,optname,optval,optlen);
}
 
static int unix_listen(struct socket *sock, int backlog)
{
        unix_socket *sk=sock->data;
        if(sk->type!=SOCK_STREAM)
                return -EOPNOTSUPP;             /* Only stream sockets accept */
        if(sk->protinfo.af_unix.name==NULL)
                return -EINVAL;                 /* No listens on an unbound socket */
        sk->max_ack_backlog=backlog;
        sk->state=TCP_LISTEN;
        return 0;
}
 
static void def_callback1(struct sock *sk)
{
        if(!sk->dead)
                wake_up_interruptible(sk->sleep);
}
 
static void def_callback2(struct sock *sk, int len)
{
        if(!sk->dead)
        {
                wake_up_interruptible(sk->sleep);
                sock_wake_async(sk->socket, 1);
        }
}
 
static void def_callback3(struct sock *sk)
{
        if(!sk->dead)
        {
                wake_up_interruptible(sk->sleep);
                sock_wake_async(sk->socket, 2);
        }
}
 
static int unix_create(struct socket *sock, int protocol)
{
        unix_socket *sk;
        if(protocol && protocol != PF_UNIX)
                return -EPROTONOSUPPORT;
        sk=(unix_socket *)sk_alloc(GFP_KERNEL);
        if(sk==NULL)
                return -ENOMEM;
        switch(sock->type)
        {
                case SOCK_STREAM:
                        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:
                        break;
                default:
                        sk_free(sk);
                        return -ESOCKTNOSUPPORT;
        }
        sk->type=sock->type;
        init_timer(&sk->timer);
        skb_queue_head_init(&sk->write_queue);
        skb_queue_head_init(&sk->receive_queue);
        skb_queue_head_init(&sk->back_log);
        sk->protinfo.af_unix.family=AF_UNIX;
        sk->protinfo.af_unix.inode=NULL;
        sk->protinfo.af_unix.locks=1;           /* Us */
        sk->protinfo.af_unix.readsem=MUTEX;     /* single task reading lock */
        sk->rcvbuf=SK_RMEM_MAX;
        sk->sndbuf=SK_WMEM_MAX;
        sk->allocation=GFP_KERNEL;
        sk->state=TCP_CLOSE;
        sk->priority=SOPRI_NORMAL;
        sk->state_change=def_callback1;
        sk->data_ready=def_callback2;
        sk->write_space=def_callback3;
        sk->error_report=def_callback1;
        sk->mtu=4096;
        sk->socket=sock;
        sock->data=(void *)sk;
        sk->sleep=sock->wait;
        unix_insert_socket(sk);
        return 0;
}
 
static int unix_dup(struct socket *newsock, struct socket *oldsock)
{
        return unix_create(newsock,0);
}
 
static int unix_release(struct socket *sock, struct socket *peer)
{
        unix_socket *sk=sock->data;
        unix_socket *skpair;
 
        /* May not have data attached */
 
        if(sk==NULL)
                return 0;
 
        sk->state_change(sk);
        sk->dead=1;
        skpair=(unix_socket *)sk->protinfo.af_unix.other;       /* Person we send to (default) */
        if(sk->type==SOCK_STREAM && skpair!=NULL && skpair->state!=TCP_LISTEN)
        {
                skpair->shutdown=SHUTDOWN_MASK;         /* No more writes */
                skpair->state_change(skpair);           /* Wake any blocked writes */
        }
        if(skpair!=NULL)
                skpair->protinfo.af_unix.locks--;       /* It may now die */
        sk->protinfo.af_unix.other=NULL;                /* No pair */
        unix_destroy_socket(sk);                        /* Try to flush out this socket. Throw out buffers at least */
        unix_gc();                                      /* Garbage collect fds */
 
        /*
         *      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.
         */
 
        sock->data = NULL;
        sk->socket = NULL;
 
        return 0;
}
 
 
static unix_socket *unix_find_other(char *path, int *error)
{
        int old_fs;
        int err;
        struct inode *inode;
        unix_socket *u;
 
        old_fs=get_fs();
        set_fs(get_ds());
        err = open_namei(path, 2, S_IFSOCK, &inode, NULL);
        set_fs(old_fs);
        if(err<0)
        {
                *error=err;
                return NULL;
        }
        u=unix_find_socket(inode);
        iput(inode);
        if(u==NULL)
        {
                *error=-ECONNREFUSED;
                return NULL;
        }
        return u;
}
 
 
static int unix_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
{
        struct sockaddr_un *sunaddr=(struct sockaddr_un *)uaddr;
        unix_socket *sk=sock->data;
        int old_fs;
        int err;
 
        if(sk->protinfo.af_unix.name)
                return -EINVAL;         /* Already bound */
 
        if(addr_len>sizeof(struct sockaddr_un) || addr_len<3 || sunaddr->sun_family!=AF_UNIX)
                return -EINVAL;
        unix_mkname(sunaddr, addr_len);
        /*
         *      Put ourselves in the filesystem
         */
        if(sk->protinfo.af_unix.inode!=NULL)
                return -EINVAL;
 
        sk->protinfo.af_unix.name=kmalloc(addr_len+1, GFP_KERNEL);
        if(sk->protinfo.af_unix.name==NULL)
                return -ENOMEM;
        memcpy(sk->protinfo.af_unix.name, sunaddr->sun_path, addr_len+1);
 
        old_fs=get_fs();
        set_fs(get_ds());
 
        err=do_mknod(sk->protinfo.af_unix.name,S_IFSOCK|S_IRWXUGO,0);
        if(err==0)
                err=open_namei(sk->protinfo.af_unix.name, 2, S_IFSOCK, &sk->protinfo.af_unix.inode, NULL);
 
        set_fs(old_fs);
 
        if(err<0)
        {
                kfree_s(sk->protinfo.af_unix.name,addr_len+1);
                sk->protinfo.af_unix.name=NULL;
                if(err==-EEXIST)
                        return -EADDRINUSE;
                else
                        return err;
        }
 
        return 0;
 
}
 
static int unix_connect(struct socket *sock, struct sockaddr *uaddr, int addr_len, int flags)
{
        unix_socket *sk=sock->data;
        struct sockaddr_un *sunaddr=(struct sockaddr_un *)uaddr;
        unix_socket *other;
        struct sk_buff *skb;
        int err;
 
        if(sk->type==SOCK_STREAM && sk->protinfo.af_unix.other)
        {
                if(sock->state==SS_CONNECTING && sk->state==TCP_ESTABLISHED)
                {
                        sock->state=SS_CONNECTED;
                        return 0;
                }
                if(sock->state==SS_CONNECTING && sk->state == TCP_CLOSE)
                {
                        sock->state=SS_UNCONNECTED;
                        return -ECONNREFUSED;
                }
                if(sock->state!=SS_CONNECTING)
                        return -EISCONN;
                if(flags&O_NONBLOCK)
                        return -EALREADY;
                /*
                 *      Drop through the connect up logic to the wait.
                 */
        }
 
        if(addr_len < sizeof(sunaddr->sun_family)+1 || sunaddr->sun_family!=AF_UNIX)
                return -EINVAL;
 
        unix_mkname(sunaddr, addr_len);
 
        if(sk->type==SOCK_DGRAM)
        {
                if(sk->protinfo.af_unix.other)
                {
                        sk->protinfo.af_unix.other->protinfo.af_unix.locks--;
                        sk->protinfo.af_unix.other=NULL;
                        sock->state=SS_UNCONNECTED;
                }
                other=unix_find_other(sunaddr->sun_path, &err);
                if(other==NULL)
                        return err;
                if(other->type!=sk->type)
                        return -EPROTOTYPE;
                other->protinfo.af_unix.locks++;
                sk->protinfo.af_unix.other=other;
                sock->state=SS_CONNECTED;
                sk->state=TCP_ESTABLISHED;
                return 0;                        /* Done */
        }
 
 
        if(sock->state==SS_UNCONNECTED)
        {
                /*
                 *      Now ready to connect
                 */
 
                skb=sock_alloc_send_skb(sk, 0, 0, 0, &err); /* Marker object */
                if(skb==NULL)
                        return err;
                skb->sk=sk;                             /* So they know it is us */
                skb->free=1;
                skb->h.filp=NULL;
                sk->state=TCP_CLOSE;
                unix_mkname(sunaddr, addr_len);
                other=unix_find_other(sunaddr->sun_path, &err);
                if(other==NULL)
                {
                        kfree_skb(skb, FREE_WRITE);
                        return err;
                }
                if(other->type!=sk->type)
                {
                        kfree_skb(skb, FREE_WRITE);
                        return -EPROTOTYPE;
                }
                other->protinfo.af_unix.locks++;                /* Lock the other socket so it doesn't run off for a moment */
                other->ack_backlog++;
                sk->protinfo.af_unix.other=other;
                skb_queue_tail(&other->receive_queue,skb);
                sk->state=TCP_SYN_SENT;
                sock->state=SS_CONNECTING;
                sti();
                other->data_ready(other,0);              /* Wake up ! */
        }
 
 
        /* Wait for an accept */
 
        cli();
        while(sk->state==TCP_SYN_SENT)
        {
                if(flags&O_NONBLOCK)
                {
                        sti();
                        return -EINPROGRESS;
                }
                interruptible_sleep_on(sk->sleep);
                if(current->signal & ~current->blocked)
                {
                        sti();
                        return -ERESTARTSYS;
                }
        }
 
        /*
         *      Has the other end closed on us ?
         */
 
        if(sk->state==TCP_CLOSE)
        {
                sk->protinfo.af_unix.other->protinfo.af_unix.locks--;
                sk->protinfo.af_unix.other=NULL;
                sock->state=SS_UNCONNECTED;
                sti();
                return -ECONNREFUSED;
        }
 
        /*
         *      Amazingly it has worked
         */
 
        sock->state=SS_CONNECTED;
        sti();
        return 0;
 
}
 
static int unix_socketpair(struct socket *a, struct socket *b)
{
        unix_socket *ska,*skb;
 
        ska=a->data;
        skb=b->data;
 
        /* Join our sockets back to back */
        ska->protinfo.af_unix.locks++;
        skb->protinfo.af_unix.locks++;
        ska->protinfo.af_unix.other=skb;
        skb->protinfo.af_unix.other=ska;
        ska->state=TCP_ESTABLISHED;
        skb->state=TCP_ESTABLISHED;
        return 0;
}
 
static int unix_accept(struct socket *sock, struct socket *newsock, int flags)
{
        unix_socket *sk=sock->data;
        unix_socket *newsk, *tsk;
        struct sk_buff *skb;
 
        if(sk->type!=SOCK_STREAM)
        {
                return -EOPNOTSUPP;
        }
        if(sk->state!=TCP_LISTEN)
        {
                return -EINVAL;
        }
 
        newsk=newsock->data;
        if(sk->protinfo.af_unix.name!=NULL)
        {
                newsk->protinfo.af_unix.name=kmalloc(strlen(sk->protinfo.af_unix.name)+1, GFP_KERNEL);
                if(newsk->protinfo.af_unix.name==NULL)
                        return -ENOMEM;
                strcpy(newsk->protinfo.af_unix.name, sk->protinfo.af_unix.name);
        }
 
        do
        {
                cli();
                skb=skb_dequeue(&sk->receive_queue);
                if(skb==NULL)
                {
                        if(flags&O_NONBLOCK)
                        {
                                sti();
                                return -EAGAIN;
                        }
                        interruptible_sleep_on(sk->sleep);
                        if(current->signal & ~current->blocked)
                        {
                                sti();
                                return -ERESTARTSYS;
                        }
                        sti();
                }
        }
        while(skb==NULL);
        tsk=skb->sk;
        kfree_skb(skb, FREE_WRITE);     /* The buffer is just used as a tag */
        sk->ack_backlog--;
        newsk->protinfo.af_unix.other=tsk;
        tsk->protinfo.af_unix.other=newsk;
        tsk->state=TCP_ESTABLISHED;
        newsk->state=TCP_ESTABLISHED;
        newsk->protinfo.af_unix.locks++;        /* Swap lock over */
        sk->protinfo.af_unix.locks--;   /* Locked to child socket not master */
        tsk->protinfo.af_unix.locks++;  /* Back lock */
        sti();
        tsk->state_change(tsk);         /* Wake up any sleeping connect */
        sock_wake_async(tsk->socket, 0);
        return 0;
}
 
static int unix_getname(struct socket *sock, struct sockaddr *uaddr, int *uaddr_len, int peer)
{
        unix_socket *sk=sock->data;
        struct sockaddr_un *sunaddr=(struct sockaddr_un *)uaddr;
 
        if(peer)
        {
                if(sk->protinfo.af_unix.other==NULL)
                        return -ENOTCONN;
                sk=sk->protinfo.af_unix.other;
        }
        sunaddr->sun_family=AF_UNIX;
        if(sk->protinfo.af_unix.name==NULL)
        {
                *sunaddr->sun_path=0;
                *uaddr_len=sizeof(sunaddr->sun_family)+1;
                return 0;                /* Not bound */
        }
        *uaddr_len=sizeof(sunaddr->sun_family)+strlen(sk->protinfo.af_unix.name)+1;
        strcpy(sunaddr->sun_path,sk->protinfo.af_unix.name);            /* 108 byte limited */
        return 0;
}
 
/*
 *      Support routines for struct cmsghdr handling
 */
 
static struct cmsghdr *unix_copyrights(void *userp, int len) /* AT&T ? */
{
        struct cmsghdr *cm;
 
        if(len>256|| len <=0)
                return NULL;
        cm=kmalloc(len, GFP_KERNEL);
        memcpy_fromfs(cm, userp, len);
        return cm;
}
 
/*
 *      Return a header block
 */
 
static void unix_returnrights(void *userp, int len, struct cmsghdr *cm)
{
        memcpy_tofs(userp, cm, len);
        kfree(cm);
}
 
/*
 *      Copy file descriptors into system space.
 *      Return number copied or negative error code
 */
 
static int unix_fd_copy(struct sock *sk, struct cmsghdr *cmsg, struct file **fp)
{
        int num=cmsg->cmsg_len-sizeof(struct cmsghdr);
        int i;
        int *fdp=(int *)cmsg->cmsg_data;
 
        num /= sizeof(int);     /* Odd bytes are forgotten in BSD not errored */
        if (num >= UNIX_MAX_FD)
                return -EINVAL;
 
        /*
         *      Verify the descriptors.
         */
 
        for(i=0; i< num; i++)
        {
                int fd;
 
                fd = fdp[i];
                if (fd < 0 || fd >= NR_OPEN)
                        return -EBADF;
                if (current->files->fd[fd]==NULL)
                        return -EBADF;
        }
 
        /* add another reference to these files */
        for(i=0; i< num; i++)
        {
                fp[i]=current->files->fd[fdp[i]];
                fp[i]->f_count++;
                unix_inflight(fp[i]);
        }
 
        return num;
}
 
/*
 *      Free the descriptors in the array
 */
 
static void unix_fd_free(struct sock *sk, struct file **fp, int num)
{
        int i;
        for(i=0;i<num;i++)
        {
                close_fp(fp[i]);
                unix_notinflight(fp[i]);
        }
}
 
 
/*
 *      Perform the AF_UNIX file descriptor pass out functionality. This
 *      is nasty and messy as is the whole design of BSD file passing.
 */
 
static void unix_detach_fds(struct sk_buff *skb, struct cmsghdr *cmsg)
{
        int i;
        /* count of space in parent for fds */
        int cmnum;
        struct file **fp;
        int *cmfptr;
        int fdnum;
 
        cmfptr = NULL;
        cmnum = 0;
        if (cmsg)
        {
                cmnum = (cmsg->cmsg_len-sizeof(struct cmsghdr)) / sizeof(int);
                cmfptr = (int *)&cmsg->cmsg_data;
        }
 
        fdnum = *(int *)skb->h.filp;
        fp = (struct file **)(skb->h.filp+sizeof(long));
 
        if (cmnum > fdnum)
                cmnum = fdnum;
 
        /*
         *      Copy those that fit
         */
        for (i = 0 ; i < cmnum ; i++)
        {
                int new_fd = get_unused_fd();
                if (new_fd < 0)
                        break;
                current->files->fd[new_fd]=fp[i];
                *cmfptr++ = new_fd;
                unix_notinflight(fp[i]);
        }
        /*
         *      Dump those that don't
         */
        for( ; i < fdnum ; i++)
        {
                close_fp(fp[i]);
                unix_notinflight(fp[i]);
        }
        kfree(skb->h.filp);
        skb->h.filp=NULL;
 
        /* no need to use destructor */
        skb->destructor = NULL;
}
 
static void unix_destruct_fds(struct sk_buff *skb)
{
        unix_detach_fds(skb,NULL);
}
 
/*
 *      Attach the file descriptor array to an sk_buff
 */
static void unix_attach_fds(int fpnum,struct file **fp,struct sk_buff *skb)
{
 
        skb->h.filp = kmalloc(sizeof(long)+fpnum*sizeof(struct file *),
                                                        GFP_KERNEL);
        /* number of descriptors starts block */
        *(int *)skb->h.filp = fpnum;
        /* actual  descriptors */
        memcpy(skb->h.filp+sizeof(long),fp,fpnum*sizeof(struct file *));
        skb->destructor = unix_destruct_fds;
}
 
/*
 *      Send AF_UNIX data.
 */
 
static int unix_sendmsg(struct socket *sock, struct msghdr *msg, int len, int nonblock, int flags)
{
        unix_socket *sk=sock->data;
        unix_socket *other;
        struct sockaddr_un *sunaddr=msg->msg_name;
        int err,size;
        struct sk_buff *skb;
        int limit=0;
        int sent=0;
        struct file *fp[UNIX_MAX_FD];
        /* number of fds waiting to be passed, 0 means either
         * no fds to pass or they've already been passed
         */
        int fpnum=0;
 
        if(sk->err)
                return sock_error(sk);
 
        if(flags&MSG_OOB)
                return -EOPNOTSUPP;
 
        if(flags)       /* For now */ {
                return -EINVAL;
        }
 
        if(sk->shutdown&SEND_SHUTDOWN)
        {
                send_sig(SIGPIPE,current,0);
                return -EPIPE;
        }
 
        if(sunaddr!=NULL)
        {
                if(sock->type==SOCK_STREAM)
                {
                        if(sk->state==TCP_ESTABLISHED)
                                return -EISCONN;
                        else
                                return -EOPNOTSUPP;
                }
        }
 
        if(sunaddr==NULL)
        {
                if(sk->protinfo.af_unix.other==NULL)
                        return -ENOTCONN;
        }
 
        /*
         *      A control message has been attached.
         */
        if(msg->msg_control)
        {
                struct cmsghdr *cm=unix_copyrights(msg->msg_control,
                                                msg->msg_controllen);
                if(cm==NULL || msg->msg_controllen<sizeof(struct cmsghdr) ||
                   cm->cmsg_type!=SCM_RIGHTS ||
                   cm->cmsg_level!=SOL_SOCKET ||
                   msg->msg_controllen!=cm->cmsg_len)
                {
                        kfree(cm);
                        return -EINVAL;
                }
                fpnum=unix_fd_copy(sk,cm,fp);
                kfree(cm);
                if(fpnum<0) {
                        return fpnum;
                }
        }
 
        while(sent < len)
        {
                /*
                 *      Optimisation for the fact that under 0.01% of X messages typically
                 *      need breaking up.
                 */
 
                size=len-sent;
 
                if(size>(sk->sndbuf-sizeof(struct sk_buff))/2)  /* Keep two messages in the pipe so it schedules better */
                {
                        if(sock->type==SOCK_DGRAM)
                        {
                                unix_fd_free(sk,fp,fpnum);
                                return -EMSGSIZE;
                        }
                        size=(sk->sndbuf-sizeof(struct sk_buff))/2;
                }
                /*
                 *      Keep to page sized kmalloc()'s as various people
                 *      have suggested. Big mallocs stress the vm too
                 *      much.
                 */
#define MAX_ALLOC (PAGE_SIZE*7/8)
                if(size > MAX_ALLOC && sock->type!=SOCK_DGRAM)
                        limit = MAX_ALLOC;      /* Fall back to 4K if we can't grab a big buffer this instant */
                else
                        limit = 0;       /* Otherwise just grab and wait */
 
                /*
                 *      Grab a buffer
                 */
 
                skb=sock_alloc_send_skb(sk,size,limit,nonblock, &err);
 
                if(skb==NULL)
                {
                        unix_fd_free(sk,fp,fpnum);
                        if(sent)
                        {
                                sk->err=-err;
                                return sent;
                        }
                        return err;
                }
                size=skb_tailroom(skb);         /* If we dropped back on a limit then our skb is smaller */
 
                skb->sk=sk;
                skb->free=1;
 
                if(fpnum)
                {
                        unix_attach_fds(fpnum,fp,skb);
                        fpnum=0;
                }
                else
                        skb->h.filp=NULL;
 
                memcpy_fromiovec(skb_put(skb,size),msg->msg_iov, size);
 
                cli();
                if(sunaddr==NULL)
                {
                        other=sk->protinfo.af_unix.other;
                        if(sock->type==SOCK_DGRAM && other->dead)
                        {
                                other->protinfo.af_unix.locks--;
                                sk->protinfo.af_unix.other=NULL;
                                sock->state=SS_UNCONNECTED;
                                sti();
                                kfree_skb(skb, FREE_WRITE);
                                /*
                                 *      Check with 1003.1g - what should
                                 *      datagram error
                                 */
                                if (!sent)
                                        sent = -ECONNRESET;
                                return sent;
                        }
                        /*
                         *      Stream sockets SIGPIPE
                         */
                        if(sock->type==SOCK_STREAM && other->dead)
                        {
                                kfree_skb(skb, FREE_WRITE);
                                sti();
                                if(!sent)
                                {
                                        send_sig(SIGPIPE,current,0);
                                        sent = -EPIPE;
                                }
                                return sent;
                        }
                }
                else
                {
                        unix_mkname(sunaddr, msg->msg_namelen);
                        other=unix_find_other(sunaddr->sun_path, &err);
                        if(other==NULL)
                        {
                                sti();
                                kfree_skb(skb, FREE_WRITE);
                                if(sent)
                                        return sent;
                                else
                                        return err;
                        }
                }
                skb_queue_tail(&other->receive_queue, skb);
                sti();
                /* if we sent an fd, only do it once */
                other->data_ready(other,size);
                sent+=size;
        }
        return sent;
}
 
/*
 *      Sleep until data has arrive. But check for races..
 */
 
static void unix_data_wait(unix_socket * sk)
{
        cli();
        if (!skb_peek(&sk->receive_queue)) {
                sk->socket->flags |= SO_WAITDATA;
                interruptible_sleep_on(sk->sleep);
                sk->socket->flags &= ~SO_WAITDATA;
        }
        sti();
}
 
static int unix_recvmsg(struct socket *sock, struct msghdr *msg, int size, int noblock, int flags, int *addr_len)
{
        unix_socket *sk=sock->data;
        struct sockaddr_un *sunaddr=msg->msg_name;
        struct sk_buff *skb;
        int copied=0;
        unsigned char *sp;
        int len;
        int num;
        struct iovec *iov=msg->msg_iov;
        struct cmsghdr *cm=NULL;
        int ct=msg->msg_iovlen;
 
        if(flags&MSG_OOB)
                return -EOPNOTSUPP;
 
        if(addr_len)
                *addr_len=0;
 
        if(sk->err)
                return sock_error(sk);
 
        if(msg->msg_control)
        {
                cm=unix_copyrights(msg->msg_control,
                        msg->msg_controllen);
                if(msg->msg_controllen<sizeof(struct cmsghdr)
#if 0 
/*              investigate this further -- Stevens example doesn't seem to care */
                ||
                   cm->cmsg_type!=SCM_RIGHTS ||
                   cm->cmsg_level!=SOL_SOCKET ||
                   msg->msg_controllen!=cm->cmsg_len
#endif
                )
                {
                        kfree(cm);
/*                      printk("recvmsg: Bad msg_control\n");*/
                        return -EINVAL;
                }
        }
 
        down(&sk->protinfo.af_unix.readsem);            /* Lock the socket */
        while(ct--)
        {
                int done=0;
                sp=iov->iov_base;
                len=iov->iov_len;
                iov++;
 
                while(done<len)
                {
                        if (copied && (flags & MSG_PEEK))
                                goto out;
                        if (copied == size)
                                goto out;
                        skb=skb_dequeue(&sk->receive_queue);
                        if(skb==NULL)
                        {
                                up(&sk->protinfo.af_unix.readsem);
                                if(sk->shutdown & RCV_SHUTDOWN)
                                        return copied;
                                if(copied)
                                        return copied;
                                if(noblock)
                                        return -EAGAIN;
                                unix_data_wait(sk);
                                if(current->signal & ~current->blocked)
                                        return -ERESTARTSYS;
                                down(&sk->protinfo.af_unix.readsem);
                                continue;
                        }
                        if(msg->msg_name!=NULL)
                        {
                                sunaddr->sun_family=AF_UNIX;
                                if(skb->sk->protinfo.af_unix.name)
                                {
                                        memcpy(sunaddr->sun_path, skb->sk->protinfo.af_unix.name, 108);
                                        if(addr_len)
                                                *addr_len=strlen(sunaddr->sun_path)+sizeof(short);
                                }
                                else
                                        if(addr_len)
                                                *addr_len=sizeof(short);
                        }
 
                        num=min(skb->len,len-done);
                        memcpy_tofs(sp, skb->data, num);
 
                        if (skb->h.filp!=NULL)
                                unix_detach_fds(skb,cm);
 
                        copied+=num;
                        done+=num;
                        sp+=num;
                        if (!(flags & MSG_PEEK))
                                skb_pull(skb, num);
                        /* put the skb back if we didn't use it up.. */
                        if (skb->len) {
                                skb_queue_head(&sk->receive_queue, skb);
                                continue;
                        }
                        kfree_skb(skb, FREE_WRITE);
                        if(sock->type==SOCK_DGRAM || cm)
                                goto out;
                }
        }
out:
        up(&sk->protinfo.af_unix.readsem);
        if(cm)
                unix_returnrights(msg->msg_control,msg->msg_controllen,cm);
        return copied;
}
 
static int unix_shutdown(struct socket *sock, int mode)
{
        unix_socket *sk=(unix_socket *)sock->data;
        unix_socket *other=sk->protinfo.af_unix.other;
 
        mode++;
 
        if(mode&SEND_SHUTDOWN)
        {
                sk->shutdown|=SEND_SHUTDOWN;
                sk->state_change(sk);
                if(other)
                {
                        other->shutdown|=RCV_SHUTDOWN;
                        other->state_change(other);
                }
        }
        other=sk->protinfo.af_unix.other;
        if(mode&RCV_SHUTDOWN)
        {
                sk->shutdown|=RCV_SHUTDOWN;
                sk->state_change(sk);
                if(other)
                {
                        other->shutdown|=SEND_SHUTDOWN;
                        other->state_change(other);
                }
        }
        return 0;
}
 
 
static int unix_select(struct socket *sock,  int sel_type, select_table *wait)
{
        return datagram_select(sock->data,sel_type,wait);
}
 
static int unix_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
{
        unix_socket *sk=sock->data;
        int err;
        long amount=0;
 
        switch(cmd)
        {
 
                case TIOCOUTQ:
                        err=verify_area(VERIFY_WRITE,(void *)arg,sizeof(unsigned long));
                        if(err)
                                return err;
                        amount=sk->sndbuf-sk->wmem_alloc;
                        if(amount<0)
                                amount=0;
                        put_fs_long(amount,(unsigned long *)arg);
                        return 0;
                case TIOCINQ:
                {
                        struct sk_buff *skb;
                        if(sk->state==TCP_LISTEN)
                                return -EINVAL;
                        /* These two are safe on a single CPU system as only user tasks fiddle here */
                        if((skb=skb_peek(&sk->receive_queue))!=NULL)
                                amount=skb->len;
                        err=verify_area(VERIFY_WRITE,(void *)arg,sizeof(unsigned long));
                        if(err)
                                return err;
                        put_fs_long(amount,(unsigned long *)arg);
                        return 0;
                }
 
                default:
                        return -EINVAL;
        }
        /*NOTREACHED*/
        return(0);
}
 
#ifdef CONFIG_PROC_FS
static int unix_get_info(char *buffer, char **start, off_t offset, int length, int dummy)
{
        off_t pos=0;
        off_t begin=0;
        int len=0;
        unix_socket *s=unix_socket_list;
 
        len+= sprintf(buffer,"Num       RefCount Protocol Flags    Type St "
            "Inode Path\n");
 
        while(s!=NULL)
        {
                len+=sprintf(buffer+len,"%p: %08X %08X %08lX %04X %02X %5ld",
                        s,
                        s->protinfo.af_unix.locks,
                        0,
                        s->socket->flags,
                        s->socket->type,
                        s->socket->state,
                        s->socket->inode ? s->socket->inode->i_ino : 0);
                if(s->protinfo.af_unix.name!=NULL)
                        len+=sprintf(buffer+len, " %s\n", s->protinfo.af_unix.name);
                else
                        buffer[len++]='\n';
 
                pos=begin+len;
                if(pos<offset)
                {
                        len=0;
                        begin=pos;
                }
                if(pos>offset+length)
                        break;
                s=s->next;
        }
        *start=buffer+(offset-begin);
        len-=(offset-begin);
        if(len>length)
                len=length;
        return len;
}
#endif
 
struct proto_ops unix_proto_ops = {
        AF_UNIX,
 
        unix_create,
        unix_dup,
        unix_release,
        unix_bind,
        unix_connect,
        unix_socketpair,
        unix_accept,
        unix_getname,
        unix_select,
        unix_ioctl,
        unix_listen,
        unix_shutdown,
        unix_setsockopt,
        unix_getsockopt,
        unix_fcntl,
        unix_sendmsg,
        unix_recvmsg
};
 
#ifdef CONFIG_PROC_FS
static struct proc_dir_entry proc_net_unix = {
        PROC_NET_UNIX,  4, "unix",
        S_IFREG | S_IRUGO, 1, 0, 0,
        0, &proc_net_inode_operations,
        unix_get_info
};
#endif
 
 
void unix_proto_init(struct net_proto *pro)
{
        printk(KERN_INFO "NET3: Unix domain sockets 0.13 for Linux NET3.035.\n");
        sock_register(unix_proto_ops.family, &unix_proto_ops);
#ifdef CONFIG_PROC_FS
        proc_net_register(&proc_net_unix);
#endif
}
/*
 * Local variables:
 *  compile-command: "gcc -g -D__KERNEL__ -Wall -O6 -I/usr/src/linux/include -c af_unix.c"
 * End:
 */
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[/] [or1k_old/] [trunk/] [uclinux/] [uClinux-2.0.x/] [net/] [unix/] [af_unix.c] - Blame information for rev 1782

Line No.	Rev	Author	Line
1	199	simons	`/*`
2			`* NET3: Implementation of BSD Unix domain sockets.`
3			`*`
4			`* Authors: Alan Cox, <alan@cymru.net>`
5			`*`
6			`* Currently this contains all but the file descriptor passing code.`
7			`* Before that goes in the odd bugs in the iovec handlers need`
8			`* fixing, and this bit testing. BSD fd passing is not a trivial part`
9			`* of the exercise it turns out. Anyone like writing garbage collectors.`
10			`*`
11			`* This program is free software; you can redistribute it and/or`
12			`* modify it under the terms of the GNU General Public License`
13			`* as published by the Free Software Foundation; either version`
14			`* 2 of the License, or (at your option) any later version.`
15			`*`
16			`* Fixes:`
17			`* Linus Torvalds : Assorted bug cures.`
18			`* Niibe Yutaka : async I/O support.`
19			`* Carsten Paeth : PF_UNIX check, address fixes.`
20			`* Alan Cox : Limit size of allocated blocks.`
21			`* Alan Cox : Fixed the stupid socketpair bug.`
22			`* Alan Cox : BSD compatibility fine tuning.`
23			`* Alan Cox : Fixed a bug in connect when interrupted.`
24			`* Alan Cox : Sorted out a proper draft version of`
25			`* file descriptor passing hacked up from`
26			`* Mike Shaver's work.`
27			`* Marty Leisner : Fixes to fd passing`
28			`* Nick Nevin : recvmsg bugfix.`
29			`* Alan Cox : Started proper garbage collector`
30			`* Heiko EiBfeldt : Missing verify_area check`
31			`* Alan Cox : Shutdown() bug`
32			`*`
33			`* Known differences from reference BSD that was tested:`
34			`*`
35			`* [TO FIX]`
36			`* ECONNREFUSED is not returned from one end of a connected() socket to the`
37			`* other the moment one end closes.`
38			`* fstat() doesn't return st_dev=NODEV, and give the blksize as high water mark`
39			`* and a fake inode identifier (nor the BSD first socket fstat twice bug).`
40			`* [NOT TO FIX]`