519e1550e2e785fb99349b676f13a83bb497336e
[safe/jmp/linux-2.6] / drivers / net / wan / hdlc_ppp.c
1 /*
2  * Generic HDLC support routines for Linux
3  * Point-to-point protocol support
4  *
5  * Copyright (C) 1999 - 2006 Krzysztof Halasa <khc@pm.waw.pl>
6  *
7  * This program is free software; you can redistribute it and/or modify it
8  * under the terms of version 2 of the GNU General Public License
9  * as published by the Free Software Foundation.
10  */
11
12 #include <linux/module.h>
13 #include <linux/kernel.h>
14 #include <linux/slab.h>
15 #include <linux/poll.h>
16 #include <linux/errno.h>
17 #include <linux/if_arp.h>
18 #include <linux/init.h>
19 #include <linux/skbuff.h>
20 #include <linux/pkt_sched.h>
21 #include <linux/inetdevice.h>
22 #include <linux/lapb.h>
23 #include <linux/rtnetlink.h>
24 #include <linux/hdlc.h>
25 #include <net/syncppp.h>
26
27 struct ppp_state {
28         struct ppp_device pppdev;
29         struct ppp_device *syncppp_ptr;
30         int (*old_change_mtu)(struct net_device *dev, int new_mtu);
31 };
32
33 static int ppp_ioctl(struct net_device *dev, struct ifreq *ifr);
34
35
36 static inline struct ppp_state* state(hdlc_device *hdlc)
37 {
38         return(struct ppp_state *)(hdlc->state);
39 }
40
41
42 static int ppp_open(struct net_device *dev)
43 {
44         hdlc_device *hdlc = dev_to_hdlc(dev);
45         int (*old_ioctl)(struct net_device *, struct ifreq *, int);
46         int result;
47
48         dev->priv = &state(hdlc)->syncppp_ptr;
49         state(hdlc)->syncppp_ptr = &state(hdlc)->pppdev;
50         state(hdlc)->pppdev.dev = dev;
51
52         old_ioctl = dev->do_ioctl;
53         state(hdlc)->old_change_mtu = dev->change_mtu;
54         sppp_attach(&state(hdlc)->pppdev);
55         /* sppp_attach nukes them. We don't need syncppp's ioctl */
56         dev->do_ioctl = old_ioctl;
57         state(hdlc)->pppdev.sppp.pp_flags &= ~PP_CISCO;
58         dev->type = ARPHRD_PPP;
59         result = sppp_open(dev);
60         if (result) {
61                 sppp_detach(dev);
62                 return result;
63         }
64
65         return 0;
66 }
67
68
69
70 static void ppp_close(struct net_device *dev)
71 {
72         hdlc_device *hdlc = dev_to_hdlc(dev);
73
74         sppp_close(dev);
75         sppp_detach(dev);
76
77         dev->change_mtu = state(hdlc)->old_change_mtu;
78         dev->mtu = HDLC_MAX_MTU;
79         dev->hard_header_len = 16;
80 }
81
82
83
84 static __be16 ppp_type_trans(struct sk_buff *skb, struct net_device *dev)
85 {
86         return __constant_htons(ETH_P_WAN_PPP);
87 }
88
89
90
91 static struct hdlc_proto proto = {
92         .open           = ppp_open,
93         .close          = ppp_close,
94         .type_trans     = ppp_type_trans,
95         .ioctl          = ppp_ioctl,
96         .module         = THIS_MODULE,
97 };
98
99
100 static int ppp_ioctl(struct net_device *dev, struct ifreq *ifr)
101 {
102         hdlc_device *hdlc = dev_to_hdlc(dev);
103         int result;
104
105         switch (ifr->ifr_settings.type) {
106         case IF_GET_PROTO:
107                 if (dev_to_hdlc(dev)->proto != &proto)
108                         return -EINVAL;
109                 ifr->ifr_settings.type = IF_PROTO_PPP;
110                 return 0; /* return protocol only, no settable parameters */
111
112         case IF_PROTO_PPP:
113                 if(!capable(CAP_NET_ADMIN))
114                         return -EPERM;
115
116                 if(dev->flags & IFF_UP)
117                         return -EBUSY;
118
119                 /* no settable parameters */
120
121                 result=hdlc->attach(dev, ENCODING_NRZ,PARITY_CRC16_PR1_CCITT);
122                 if (result)
123                         return result;
124
125                 result = attach_hdlc_protocol(dev, &proto, NULL,
126                                               sizeof(struct ppp_state));
127                 if (result)
128                         return result;
129                 dev->hard_start_xmit = hdlc->xmit;
130                 dev->type = ARPHRD_PPP;
131                 netif_dormant_off(dev);
132                 return 0;
133         }
134
135         return -EINVAL;
136 }
137
138
139 static int __init mod_init(void)
140 {
141         register_hdlc_protocol(&proto);
142         return 0;
143 }
144
145
146
147 static void __exit mod_exit(void)
148 {
149         unregister_hdlc_protocol(&proto);
150 }
151
152
153 module_init(mod_init);
154 module_exit(mod_exit);
155
156 MODULE_AUTHOR("Krzysztof Halasa <khc@pm.waw.pl>");
157 MODULE_DESCRIPTION("PPP protocol support for generic HDLC");
158 MODULE_LICENSE("GPL v2");