xref: /linux/net/atm/ioctl.c (revision 14b42963f64b98ab61fa9723c03d71aa5ef4f862)
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/module.h>
8 #include <linux/kmod.h>
9 #include <linux/net.h>		/* struct socket, struct proto_ops */
10 #include <linux/atm.h>		/* ATM stuff */
11 #include <linux/atmdev.h>
12 #include <linux/atmclip.h>	/* CLIP_*ENCAP */
13 #include <linux/atmarp.h>	/* manifest constants */
14 #include <linux/capability.h>
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 <linux/mutex.h>
21 #include <asm/ioctls.h>
22 
23 #include "resources.h"
24 #include "signaling.h"		/* for WAITING and sigd_attach */
25 #include "common.h"
26 
27 
28 static DEFINE_MUTEX(ioctl_mutex);
29 static LIST_HEAD(ioctl_list);
30 
31 
32 void register_atm_ioctl(struct atm_ioctl *ioctl)
33 {
34 	mutex_lock(&ioctl_mutex);
35 	list_add_tail(&ioctl->list, &ioctl_list);
36 	mutex_unlock(&ioctl_mutex);
37 }
38 
39 void deregister_atm_ioctl(struct atm_ioctl *ioctl)
40 {
41 	mutex_lock(&ioctl_mutex);
42 	list_del(&ioctl->list);
43 	mutex_unlock(&ioctl_mutex);
44 }
45 
46 EXPORT_SYMBOL(register_atm_ioctl);
47 EXPORT_SYMBOL(deregister_atm_ioctl);
48 
49 int vcc_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
50 {
51 	struct sock *sk = sock->sk;
52 	struct atm_vcc *vcc;
53 	int error;
54 	struct list_head * pos;
55 	void __user *argp = (void __user *)arg;
56 
57 	vcc = ATM_SD(sock);
58 	switch (cmd) {
59 		case SIOCOUTQ:
60 			if (sock->state != SS_CONNECTED ||
61 			    !test_bit(ATM_VF_READY, &vcc->flags)) {
62 				error =  -EINVAL;
63 				goto done;
64 			}
65 			error = put_user(sk->sk_sndbuf -
66 					 atomic_read(&sk->sk_wmem_alloc),
67 					 (int __user *) argp) ? -EFAULT : 0;
68 			goto done;
69 		case SIOCINQ:
70 			{
71 				struct sk_buff *skb;
72 
73 				if (sock->state != SS_CONNECTED) {
74 					error = -EINVAL;
75 					goto done;
76 				}
77 				skb = skb_peek(&sk->sk_receive_queue);
78 				error = put_user(skb ? skb->len : 0,
79 					 	 (int __user *)argp) ? -EFAULT : 0;
80 				goto done;
81 			}
82 		case SIOCGSTAMP: /* borrowed from IP */
83 			error = sock_get_timestamp(sk, argp);
84 			goto done;
85 		case ATM_SETSC:
86 			printk(KERN_WARNING "ATM_SETSC is obsolete\n");
87 			error = 0;
88 			goto done;
89 		case ATMSIGD_CTRL:
90 			if (!capable(CAP_NET_ADMIN)) {
91 				error = -EPERM;
92 				goto done;
93 			}
94 			/*
95 			 * The user/kernel protocol for exchanging signalling
96 			 * info uses kernel pointers as opaque references,
97 			 * so the holder of the file descriptor can scribble
98 			 * on the kernel... so we should make sure that we
99 			 * have the same privledges that /proc/kcore needs
100 			 */
101 			if (!capable(CAP_SYS_RAWIO)) {
102 				error = -EPERM;
103 				goto done;
104 			}
105 			error = sigd_attach(vcc);
106 			if (!error)
107 				sock->state = SS_CONNECTED;
108 			goto done;
109 		case ATM_SETBACKEND:
110 		case ATM_NEWBACKENDIF:
111 			{
112 				atm_backend_t backend;
113 				error = get_user(backend, (atm_backend_t __user *) argp);
114 				if (error)
115 					goto done;
116 				switch (backend) {
117 					case ATM_BACKEND_PPP:
118 						request_module("pppoatm");
119 						break;
120 					case ATM_BACKEND_BR2684:
121 						request_module("br2684");
122 						break;
123 				}
124 			}
125 			break;
126 		case ATMMPC_CTRL:
127 		case ATMMPC_DATA:
128 			request_module("mpoa");
129 			break;
130 		case ATMARPD_CTRL:
131 			request_module("clip");
132 			break;
133 		case ATMLEC_CTRL:
134 			request_module("lec");
135 			break;
136 	}
137 
138 	error = -ENOIOCTLCMD;
139 
140 	mutex_lock(&ioctl_mutex);
141 	list_for_each(pos, &ioctl_list) {
142 		struct atm_ioctl * ic = list_entry(pos, struct atm_ioctl, list);
143 		if (try_module_get(ic->owner)) {
144 			error = ic->ioctl(sock, cmd, arg);
145 			module_put(ic->owner);
146 			if (error != -ENOIOCTLCMD)
147 				break;
148 		}
149 	}
150 	mutex_unlock(&ioctl_mutex);
151 
152 	if (error != -ENOIOCTLCMD)
153 		goto done;
154 
155 	error = atm_dev_ioctl(cmd, argp);
156 
157 done:
158 	return error;
159 }
160