net/atm/ioctl.c

   1 /* ATM ioctl handling */
   2
   3 /* Written 1995-2000 by Werner Almesberger, EPFL LRC/ICA */
   4 /* 2003 John Levon  <levon@movementarian.org> */
   5
   6
   7 #include <linux/config.h>
   8 #include <linux/module.h>
   9 #include <linux/kmod.h>
  10 #include <linux/net.h>          /* struct socket, struct proto_ops */
  11 #include <linux/atm.h>          /* ATM stuff */
  12 #include <linux/atmdev.h>
  13 #include <linux/atmclip.h>      /* CLIP_*ENCAP */
  14 #include <linux/atmarp.h>       /* manifest constants */
  15 #include <linux/sonet.h>        /* for ioctls */
  16 #include <linux/atmsvc.h>
  17 #include <linux/atmmpc.h>
  18 #include <net/atmclip.h>
  19 #include <linux/atmlec.h>
  20 #include <asm/ioctls.h>
  21
  22 #include "resources.h"
  23 #include "signaling.h"          /* for WAITING and sigd_attach */
  24
  25
  26 static DECLARE_MUTEX(ioctl_mutex);
  27 static LIST_HEAD(ioctl_list);
  28
  29
  30 void register_atm_ioctl(struct atm_ioctl *ioctl)
  31 {
  32         down(&ioctl_mutex);
  33         list_add_tail(&ioctl->list, &ioctl_list);
  34         up(&ioctl_mutex);
  35 }
  36
  37 void deregister_atm_ioctl(struct atm_ioctl *ioctl)
  38 {
  39         down(&ioctl_mutex);
  40         list_del(&ioctl->list);
  41         up(&ioctl_mutex);
  42 }
  43
  44 EXPORT_SYMBOL(register_atm_ioctl);
  45 EXPORT_SYMBOL(deregister_atm_ioctl);
  46
  47 int vcc_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
  48 {
  49         struct sock *sk = sock->sk;
  50         struct atm_vcc *vcc;
  51         int error;
  52         struct list_head * pos;
  53         void __user *argp = (void __user *)arg;
  54
  55         vcc = ATM_SD(sock);
  56         switch (cmd) {
  57                 case SIOCOUTQ:
  58                         if (sock->state != SS_CONNECTED ||
  59                             !test_bit(ATM_VF_READY, &vcc->flags)) {
  60                                 error =  -EINVAL;
  61                                 goto done;
  62                         }
  63                         error = put_user(sk->sk_sndbuf -
  64                                          atomic_read(&sk->sk_wmem_alloc),
  65                                          (int __user *) argp) ? -EFAULT : 0;
  66                         goto done;
  67                 case SIOCINQ:
  68                         {
  69                                 struct sk_buff *skb;
  70
  71                                 if (sock->state != SS_CONNECTED) {
  72                                         error = -EINVAL;
  73                                         goto done;
  74                                 }
  75                                 skb = skb_peek(&sk->sk_receive_queue);
  76                                 error = put_user(skb ? skb->len : 0,
  77                                                  (int __user *)argp) ? -EFAULT : 0;
  78                                 goto done;
  79                         }
  80                 case SIOCGSTAMP: /* borrowed from IP */
  81                         error = sock_get_timestamp(sk, argp);
  82                         goto done;
  83                 case ATM_SETSC:
  84                         printk(KERN_WARNING "ATM_SETSC is obsolete\n");
  85                         error = 0;
  86                         goto done;
  87                 case ATMSIGD_CTRL:
  88                         if (!capable(CAP_NET_ADMIN)) {
  89                                 error = -EPERM;
  90                                 goto done;
  91                         }
  92                         /*
  93                          * The user/kernel protocol for exchanging signalling
  94                          * info uses kernel pointers as opaque references,
  95                          * so the holder of the file descriptor can scribble
  96                          * on the kernel... so we should make sure that we
  97                          * have the same privledges that /proc/kcore needs
  98                          */
  99                         if (!capable(CAP_SYS_RAWIO)) {
 100                                 error = -EPERM;
 101                                 goto done;
 102                         }
 103                         error = sigd_attach(vcc);
 104                         if (!error)
 105                                 sock->state = SS_CONNECTED;
 106                         goto done;
 107                 default:
 108                         break;
 109         }
 110
 111         if (cmd == ATMMPC_CTRL || cmd == ATMMPC_DATA)
 112                 request_module("mpoa");
 113         if (cmd == ATMARPD_CTRL)
 114                 request_module("clip");
 115         if (cmd == ATMLEC_CTRL)
 116                 request_module("lec");
 117
 118         error = -ENOIOCTLCMD;
 119
 120         down(&ioctl_mutex);
 121         list_for_each(pos, &ioctl_list) {
 122                 struct atm_ioctl * ic = list_entry(pos, struct atm_ioctl, list);
 123                 if (try_module_get(ic->owner)) {
 124                         error = ic->ioctl(sock, cmd, arg);
 125                         module_put(ic->owner);
 126                         if (error != -ENOIOCTLCMD)
 127                                 break;
 128                 }
 129         }
 130         up(&ioctl_mutex);
 131
 132         if (error != -ENOIOCTLCMD)
 133                 goto done;
 134
 135         error = atm_dev_ioctl(cmd, argp);
 136
 137 done:
 138         return error;
 139 }