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 #include "common.h"
  25
  26
  27 static DECLARE_MUTEX(ioctl_mutex);
  28 static LIST_HEAD(ioctl_list);
  29
  30
  31 void register_atm_ioctl(struct atm_ioctl *ioctl)
  32 {
  33         down(&ioctl_mutex);
  34         list_add_tail(&ioctl->list, &ioctl_list);
  35         up(&ioctl_mutex);
  36 }
  37
  38 void deregister_atm_ioctl(struct atm_ioctl *ioctl)
  39 {
  40         down(&ioctl_mutex);
  41         list_del(&ioctl->list);
  42         up(&ioctl_mutex);
  43 }
  44
  45 EXPORT_SYMBOL(register_atm_ioctl);
  46 EXPORT_SYMBOL(deregister_atm_ioctl);
  47
  48 int vcc_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
  49 {
  50         struct sock *sk = sock->sk;
  51         struct atm_vcc *vcc;
  52         int error;
  53         struct list_head * pos;
  54         void __user *argp = (void __user *)arg;
  55
  56         vcc = ATM_SD(sock);
  57         switch (cmd) {
  58                 case SIOCOUTQ:
  59                         if (sock->state != SS_CONNECTED ||
  60                             !test_bit(ATM_VF_READY, &vcc->flags)) {
  61                                 error =  -EINVAL;
  62                                 goto done;
  63                         }
  64                         error = put_user(sk->sk_sndbuf -
  65                                          atomic_read(&sk->sk_wmem_alloc),
  66                                          (int __user *) argp) ? -EFAULT : 0;
  67                         goto done;
  68                 case SIOCINQ:
  69                         {
  70                                 struct sk_buff *skb;
  71
  72                                 if (sock->state != SS_CONNECTED) {
  73                                         error = -EINVAL;
  74                                         goto done;
  75                                 }
  76                                 skb = skb_peek(&sk->sk_receive_queue);
  77                                 error = put_user(skb ? skb->len : 0,
  78                                                  (int __user *)argp) ? -EFAULT : 0;
  79                                 goto done;
  80                         }
  81                 case SIOCGSTAMP: /* borrowed from IP */
  82                         error = sock_get_timestamp(sk, argp);
  83                         goto done;
  84                 case ATM_SETSC:
  85                         printk(KERN_WARNING "ATM_SETSC is obsolete\n");
  86                         error = 0;
  87                         goto done;
  88                 case ATMSIGD_CTRL:
  89                         if (!capable(CAP_NET_ADMIN)) {
  90                                 error = -EPERM;
  91                                 goto done;
  92                         }
  93                         /*
  94                          * The user/kernel protocol for exchanging signalling
  95                          * info uses kernel pointers as opaque references,
  96                          * so the holder of the file descriptor can scribble
  97                          * on the kernel... so we should make sure that we
  98                          * have the same privledges that /proc/kcore needs
  99                          */
 100                         if (!capable(CAP_SYS_RAWIO)) {
 101                                 error = -EPERM;
 102                                 goto done;
 103                         }
 104                         error = sigd_attach(vcc);
 105                         if (!error)
 106                                 sock->state = SS_CONNECTED;
 107                         goto done;
 108                 default:
 109                         break;
 110         }
 111
 112         if (cmd == ATMMPC_CTRL || cmd == ATMMPC_DATA)
 113                 request_module("mpoa");
 114         if (cmd == ATMARPD_CTRL)
 115                 request_module("clip");
 116         if (cmd == ATMLEC_CTRL)
 117                 request_module("lec");
 118
 119         error = -ENOIOCTLCMD;
 120
 121         down(&ioctl_mutex);
 122         list_for_each(pos, &ioctl_list) {
 123                 struct atm_ioctl * ic = list_entry(pos, struct atm_ioctl, list);
 124                 if (try_module_get(ic->owner)) {
 125                         error = ic->ioctl(sock, cmd, arg);
 126                         module_put(ic->owner);
 127                         if (error != -ENOIOCTLCMD)
 128                                 break;
 129                 }
 130         }
 131         up(&ioctl_mutex);
 132
 133         if (error != -ENOIOCTLCMD)
 134                 goto done;
 135
 136         error = atm_dev_ioctl(cmd, argp);
 137
 138 done:
 139         return error;
 140 }