xref: /linux/net/atm/ioctl.c (revision de2fe5e07d58424bc286fff3fd3c1b0bf933cd58)
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87 			printk(KERN_WARNING "ATM_SETSC is obsolete\n");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 }
161