1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /** -*- linux-c -*- *********************************************************** 3 * Linux PPP over X/Ethernet (PPPoX/PPPoE) Sockets 4 * 5 * PPPoX --- Generic PPP encapsulation socket family 6 * PPPoE --- PPP over Ethernet (RFC 2516) 7 * 8 * Version: 0.5.2 9 * 10 * Author: Michal Ostrowski <mostrows@speakeasy.net> 11 * 12 * 051000 : Initialization cleanup 13 * 14 * License: 15 */ 16 17 #include <linux/string.h> 18 #include <linux/module.h> 19 #include <linux/kernel.h> 20 #include <linux/errno.h> 21 #include <linux/netdevice.h> 22 #include <linux/net.h> 23 #include <linux/init.h> 24 #include <linux/if_pppox.h> 25 #include <linux/ppp_defs.h> 26 #include <linux/ppp-ioctl.h> 27 #include <linux/ppp_channel.h> 28 #include <linux/kmod.h> 29 30 #include <net/sock.h> 31 32 #include <linux/uaccess.h> 33 34 static const struct pppox_proto *pppox_protos[PX_MAX_PROTO + 1]; 35 36 int register_pppox_proto(int proto_num, const struct pppox_proto *pp) 37 { 38 if (proto_num < 0 || proto_num > PX_MAX_PROTO) 39 return -EINVAL; 40 if (pppox_protos[proto_num]) 41 return -EALREADY; 42 pppox_protos[proto_num] = pp; 43 return 0; 44 } 45 46 void unregister_pppox_proto(int proto_num) 47 { 48 if (proto_num >= 0 && proto_num <= PX_MAX_PROTO) 49 pppox_protos[proto_num] = NULL; 50 } 51 52 void pppox_unbind_sock(struct sock *sk) 53 { 54 /* Clear connection to ppp device, if attached. */ 55 56 if (sk->sk_state & (PPPOX_BOUND | PPPOX_CONNECTED)) { 57 ppp_unregister_channel(&pppox_sk(sk)->chan); 58 sk->sk_state = PPPOX_DEAD; 59 } 60 } 61 62 EXPORT_SYMBOL(register_pppox_proto); 63 EXPORT_SYMBOL(unregister_pppox_proto); 64 EXPORT_SYMBOL(pppox_unbind_sock); 65 66 int pppox_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg) 67 { 68 struct sock *sk = sock->sk; 69 struct pppox_sock *po = pppox_sk(sk); 70 int rc; 71 72 lock_sock(sk); 73 74 switch (cmd) { 75 case PPPIOCGCHAN: { 76 int index; 77 rc = -ENOTCONN; 78 if (!(sk->sk_state & PPPOX_CONNECTED)) 79 break; 80 81 rc = -EINVAL; 82 index = ppp_channel_index(&po->chan); 83 if (put_user(index , (int __user *) arg)) 84 break; 85 86 rc = 0; 87 sk->sk_state |= PPPOX_BOUND; 88 break; 89 } 90 default: 91 rc = pppox_protos[sk->sk_protocol]->ioctl ? 92 pppox_protos[sk->sk_protocol]->ioctl(sock, cmd, arg) : -ENOTTY; 93 } 94 95 release_sock(sk); 96 return rc; 97 } 98 99 EXPORT_SYMBOL(pppox_ioctl); 100 101 static int pppox_create(struct net *net, struct socket *sock, int protocol, 102 int kern) 103 { 104 int rc = -EPROTOTYPE; 105 106 if (protocol < 0 || protocol > PX_MAX_PROTO) 107 goto out; 108 109 rc = -EPROTONOSUPPORT; 110 if (!pppox_protos[protocol]) 111 request_module("net-pf-%d-proto-%d", PF_PPPOX, protocol); 112 if (!pppox_protos[protocol] || 113 !try_module_get(pppox_protos[protocol]->owner)) 114 goto out; 115 116 rc = pppox_protos[protocol]->create(net, sock, kern); 117 118 module_put(pppox_protos[protocol]->owner); 119 out: 120 return rc; 121 } 122 123 static const struct net_proto_family pppox_proto_family = { 124 .family = PF_PPPOX, 125 .create = pppox_create, 126 .owner = THIS_MODULE, 127 }; 128 129 static int __init pppox_init(void) 130 { 131 return sock_register(&pppox_proto_family); 132 } 133 134 static void __exit pppox_exit(void) 135 { 136 sock_unregister(PF_PPPOX); 137 } 138 139 module_init(pppox_init); 140 module_exit(pppox_exit); 141 142 MODULE_AUTHOR("Michal Ostrowski <mostrows@speakeasy.net>"); 143 MODULE_DESCRIPTION("PPP over Ethernet driver (generic socket layer)"); 144 MODULE_LICENSE("GPL"); 145 MODULE_ALIAS_NETPROTO(PF_PPPOX); 146