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/capability.h>
  16 #include <linux/sonet.h>        /* for ioctls */
  17 #include <linux/atmsvc.h>
  18 #include <linux/atmmpc.h>
  19 #include <net/atmclip.h>
  20 #include <linux/atmlec.h>
  21 #include <linux/mutex.h>
  22 #include <asm/ioctls.h>
  23
  24 #include "resources.h"
  25 #include "signaling.h"          /* for WAITING and sigd_attach */
  26 #include "common.h"
  27
  28
  29 static DEFINE_MUTEX(ioctl_mutex);
  30 static LIST_HEAD(ioctl_list);
  31
  32
  33 void register_atm_ioctl(struct atm_ioctl *ioctl)
  34 {
  35         mutex_lock(&ioctl_mutex);
  36         list_add_tail(&ioctl->list, &ioctl_list);
  37         mutex_unlock(&ioctl_mutex);
  38 }
  39
  40 void deregister_atm_ioctl(struct atm_ioctl *ioctl)
  41 {
  42         mutex_lock(&ioctl_mutex);
  43         list_del(&ioctl->list);
  44         mutex_unlock(&ioctl_mutex);
  45 }
  46
  47 EXPORT_SYMBOL(register_atm_ioctl);
  48 EXPORT_SYMBOL(deregister_atm_ioctl);
  49
  50 int vcc_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
  51 {
  52         struct sock *sk = sock->sk;
  53         struct atm_vcc *vcc;
  54         int error;
  55         struct list_head * pos;
  56         void __user *argp = (void __user *)arg;
  57
  58         vcc = ATM_SD(sock);
  59         switch (cmd) {
  60                 case SIOCOUTQ:
  61                         if (sock->state != SS_CONNECTED ||
  62                             !test_bit(ATM_VF_READY, &vcc->flags)) {
  63                                 error =  -EINVAL;
  64                                 goto done;
  65                         }
  66                         error = put_user(sk->sk_sndbuf -
  67                                          atomic_read(&sk->sk_wmem_alloc),
  68                                          (int __user *) argp) ? -EFAULT : 0;
  69                         goto done;
  70                 case SIOCINQ:
  71                         {
  72                                 struct sk_buff *skb;
  73
  74                                 if (sock->state != SS_CONNECTED) {
  75                                         error = -EINVAL;
  76                                         goto done;
  77                                 }
  78                                 skb = skb_peek(&sk->sk_receive_queue);
  79                                 error = put_user(skb ? skb->len : 0,
  80                                                  (int __user *)argp) ? -EFAULT : 0;
  81                                 goto done;
  82                         }
  83                 case SIOCGSTAMP: /* borrowed from IP */
  84                         error = sock_get_timestamp(sk, argp);
  85                         goto done;
  86                 case ATM_SETSC:
  87                         printk(KERN_WARNING "ATM_SETSC is obsolete\n");
  88                         error = 0;
  89                         goto done;
  90                 case ATMSIGD_CTRL:
  91                         if (!capable(CAP_NET_ADMIN)) {
  92                                 error = -EPERM;
  93                                 goto done;
  94                         }
  95                         /*
  96                          * The user/kernel protocol for exchanging signalling
  97                          * info uses kernel pointers as opaque references,
  98                          * so the holder of the file descriptor can scribble
  99                          * on the kernel... so we should make sure that we
 100                          * have the same privledges that /proc/kcore needs
 101                          */
 102                         if (!capable(CAP_SYS_RAWIO)) {
 103                                 error = -EPERM;
 104                                 goto done;
 105                         }
 106                         error = sigd_attach(vcc);
 107                         if (!error)
 108                                 sock->state = SS_CONNECTED;
 109                         goto done;
 110                 case ATM_SETBACKEND:
 111                 case ATM_NEWBACKENDIF:
 112                         {
 113                                 atm_backend_t backend;
 114                                 error = get_user(backend, (atm_backend_t __user *) argp);
 115                                 if (error)
 116                                         goto done;
 117                                 switch (backend) {
 118                                         case ATM_BACKEND_PPP:
 119                                                 request_module("pppoatm");
 120                                                 break;
 121                                         case ATM_BACKEND_BR2684:
 122                                                 request_module("br2684");
 123                                                 break;
 124                                 }
 125                         }
 126                         break;
 127                 case ATMMPC_CTRL:
 128                 case ATMMPC_DATA:
 129                         request_module("mpoa");
 130                         break;
 131                 case ATMARPD_CTRL:
 132                         request_module("clip");
 133                         break;
 134                 case ATMLEC_CTRL:
 135                         request_module("lec");
 136                         break;
 137         }
 138
 139         error = -ENOIOCTLCMD;
 140
 141         mutex_lock(&ioctl_mutex);
 142         list_for_each(pos, &ioctl_list) {
 143                 struct atm_ioctl * ic = list_entry(pos, struct atm_ioctl, list);
 144                 if (try_module_get(ic->owner)) {
 145                         error = ic->ioctl(sock, cmd, arg);
 146                         module_put(ic->owner);
 147                         if (error != -ENOIOCTLCMD)
 148                                 break;
 149                 }
 150         }
 151         mutex_unlock(&ioctl_mutex);
 152
 153         if (error != -ENOIOCTLCMD)
 154                 goto done;
 155
 156         error = atm_dev_ioctl(cmd, argp);
 157
 158 done:
 159         return error;
 160 }