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->ml_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, 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"); 159