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  83                         printk(KERN_WARNING "ATM_SETSC is obsolete\n");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