[deliverable/linux.git] / drivers / net / ppp / pptp.c

/*
 *  Point-to-Point Tunneling Protocol for Linux
 *
 *	Authors: Dmitry Kozlov <xeb@mail.ru>
 *
 *	This program is free software; you can redistribute it and/or
 *	modify it under the terms of the GNU General Public License
 *	as published by the Free Software Foundation; either version
 *	2 of the License, or (at your option) any later version.
 *
 */

#include <linux/string.h>
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/errno.h>
#include <linux/netdevice.h>
#include <linux/net.h>
#include <linux/skbuff.h>
#include <linux/vmalloc.h>
#include <linux/init.h>
#include <linux/ppp_channel.h>
#include <linux/ppp_defs.h>
#include <linux/if_pppox.h>
#include <linux/ppp-ioctl.h>
#include <linux/notifier.h>
#include <linux/file.h>
#include <linux/in.h>
#include <linux/ip.h>
#include <linux/rcupdate.h>
#include <linux/spinlock.h>

#include <net/sock.h>
#include <net/protocol.h>
#include <net/ip.h>
#include <net/icmp.h>
#include <net/route.h>
#include <net/gre.h>

#include <linux/uaccess.h>

#define PPTP_DRIVER_VERSION "0.8.5"

#define MAX_CALLID 65535

static DECLARE_BITMAP(callid_bitmap, MAX_CALLID + 1);
static struct pppox_sock __rcu **callid_sock;

static DEFINE_SPINLOCK(chan_lock);

static struct proto pptp_sk_proto __read_mostly;
static const struct ppp_channel_ops pptp_chan_ops;
static const struct proto_ops pptp_ops;

#define PPP_LCP_ECHOREQ 0x09
#define PPP_LCP_ECHOREP 0x0A
#define SC_RCV_BITS	(SC_RCV_B7_1|SC_RCV_B7_0|SC_RCV_ODDP|SC_RCV_EVNP)

#define MISSING_WINDOW 20
#define WRAPPED(curseq, lastseq)\
	((((curseq) & 0xffffff00) == 0) &&\
	(((lastseq) & 0xffffff00) == 0xffffff00))

#define PPTP_GRE_PROTO  0x880B
#define PPTP_GRE_VER    0x1

#define PPTP_GRE_FLAG_C	0x80
#define PPTP_GRE_FLAG_R	0x40
#define PPTP_GRE_FLAG_K	0x20
#define PPTP_GRE_FLAG_S	0x10
#define PPTP_GRE_FLAG_A	0x80

#define PPTP_GRE_IS_C(f) ((f)&PPTP_GRE_FLAG_C)
#define PPTP_GRE_IS_R(f) ((f)&PPTP_GRE_FLAG_R)
#define PPTP_GRE_IS_K(f) ((f)&PPTP_GRE_FLAG_K)
#define PPTP_GRE_IS_S(f) ((f)&PPTP_GRE_FLAG_S)
#define PPTP_GRE_IS_A(f) ((f)&PPTP_GRE_FLAG_A)

#define PPTP_HEADER_OVERHEAD (2+sizeof(struct pptp_gre_header))
struct pptp_gre_header {
	u8  flags;
	u8  ver;
	__be16 protocol;
	__be16 payload_len;
	__be16 call_id;
	__be32 seq;
	__be32 ack;
} __packed;

static struct pppox_sock *lookup_chan(u16 call_id, __be32 s_addr)
{
	struct pppox_sock *sock;
	struct pptp_opt *opt;

	rcu_read_lock();
	sock = rcu_dereference(callid_sock[call_id]);
	if (sock) {
		opt = &sock->proto.pptp;
		if (opt->dst_addr.sin_addr.s_addr != s_addr)
			sock = NULL;
		else
			sock_hold(sk_pppox(sock));
	}
	rcu_read_unlock();

	return sock;
}

static int lookup_chan_dst(u16 call_id, __be32 d_addr)
{
	struct pppox_sock *sock;
	struct pptp_opt *opt;
	int i;

	rcu_read_lock();
	i = 1;
	for_each_set_bit_from(i, callid_bitmap, MAX_CALLID) {
		sock = rcu_dereference(callid_sock[i]);
		if (!sock)
			continue;
		opt = &sock->proto.pptp;
		if (opt->dst_addr.call_id == call_id &&
			  opt->dst_addr.sin_addr.s_addr == d_addr)
			break;
	}
	rcu_read_unlock();

	return i < MAX_CALLID;
}

static int add_chan(struct pppox_sock *sock,
		    struct pptp_addr *sa)
{
	static int call_id;

	spin_lock(&chan_lock);
	if (!sa->call_id)	{
		call_id = find_next_zero_bit(callid_bitmap, MAX_CALLID, call_id + 1);
		if (call_id == MAX_CALLID) {
			call_id = find_next_zero_bit(callid_bitmap, MAX_CALLID, 1);
			if (call_id == MAX_CALLID)
				goto out_err;
		}
		sa->call_id = call_id;
	} else if (test_bit(sa->call_id, callid_bitmap)) {
		goto out_err;
	}

	sock->proto.pptp.src_addr = *sa;
	set_bit(sa->call_id, callid_bitmap);
	rcu_assign_pointer(callid_sock[sa->call_id], sock);
	spin_unlock(&chan_lock);

	return 0;

out_err:
	spin_unlock(&chan_lock);
	return -1;
}

static void del_chan(struct pppox_sock *sock)
{
	spin_lock(&chan_lock);
	clear_bit(sock->proto.pptp.src_addr.call_id, callid_bitmap);
	RCU_INIT_POINTER(callid_sock[sock->proto.pptp.src_addr.call_id], NULL);
	spin_unlock(&chan_lock);
	synchronize_rcu();
}

static int pptp_xmit(struct ppp_channel *chan, struct sk_buff *skb)
{
	struct sock *sk = (struct sock *) chan->private;
	struct pppox_sock *po = pppox_sk(sk);
	struct net *net = sock_net(sk);
	struct pptp_opt *opt = &po->proto.pptp;
	struct pptp_gre_header *hdr;
	unsigned int header_len = sizeof(*hdr);
	struct flowi4 fl4;
	int islcp;
	int len;
	unsigned char *data;
	__u32 seq_recv;


	struct rtable *rt;
	struct net_device *tdev;
	struct iphdr  *iph;
	int    max_headroom;

	if (sk_pppox(po)->sk_state & PPPOX_DEAD)
		goto tx_error;

	rt = ip_route_output_ports(net, &fl4, NULL,
				   opt->dst_addr.sin_addr.s_addr,
				   opt->src_addr.sin_addr.s_addr,
				   0, 0, IPPROTO_GRE,
				   RT_TOS(0), 0);
	if (IS_ERR(rt))
		goto tx_error;

	tdev = rt->dst.dev;

	max_headroom = LL_RESERVED_SPACE(tdev) + sizeof(*iph) + sizeof(*hdr) + 2;

	if (skb_headroom(skb) < max_headroom || skb_cloned(skb) || skb_shared(skb)) {
		struct sk_buff *new_skb = skb_realloc_headroom(skb, max_headroom);
		if (!new_skb) {
			ip_rt_put(rt);
			goto tx_error;
		}
		if (skb->sk)
			skb_set_owner_w(new_skb, skb->sk);
		consume_skb(skb);
		skb = new_skb;
	}

	data = skb->data;
	islcp = ((data[0] << 8) + data[1]) == PPP_LCP && 1 <= data[2] && data[2] <= 7;

	/* compress protocol field */
	if ((opt->ppp_flags & SC_COMP_PROT) && data[0] == 0 && !islcp)
		skb_pull(skb, 1);

	/* Put in the address/control bytes if necessary */
	if ((opt->ppp_flags & SC_COMP_AC) == 0 || islcp) {
		data = skb_push(skb, 2);
		data[0] = PPP_ALLSTATIONS;
		data[1] = PPP_UI;
	}

	len = skb->len;

	seq_recv = opt->seq_recv;

	if (opt->ack_sent == seq_recv)
		header_len -= sizeof(hdr->ack);

	/* Push down and install GRE header */
	skb_push(skb, header_len);
	hdr = (struct pptp_gre_header *)(skb->data);

	hdr->flags       = PPTP_GRE_FLAG_K;
	hdr->ver         = PPTP_GRE_VER;
	hdr->protocol    = htons(PPTP_GRE_PROTO);
	hdr->call_id     = htons(opt->dst_addr.call_id);

	hdr->flags      |= PPTP_GRE_FLAG_S;
	hdr->seq         = htonl(++opt->seq_sent);
	if (opt->ack_sent != seq_recv)	{
		/* send ack with this message */
		hdr->ver |= PPTP_GRE_FLAG_A;
		hdr->ack  = htonl(seq_recv);
		opt->ack_sent = seq_recv;
	}
	hdr->payload_len = htons(len);

	/*	Push down and install the IP header. */

	skb_reset_transport_header(skb);
	skb_push(skb, sizeof(*iph));
	skb_reset_network_header(skb);
	memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt));
	IPCB(skb)->flags &= ~(IPSKB_XFRM_TUNNEL_SIZE | IPSKB_XFRM_TRANSFORMED | IPSKB_REROUTED);

	iph =	ip_hdr(skb);
	iph->version =	4;
	iph->ihl =	sizeof(struct iphdr) >> 2;
	if (ip_dont_fragment(sk, &rt->dst))
		iph->frag_off	=	htons(IP_DF);
	else
		iph->frag_off	=	0;
	iph->protocol = IPPROTO_GRE;
	iph->tos      = 0;
	iph->daddr    = fl4.daddr;
	iph->saddr    = fl4.saddr;
	iph->ttl      = ip4_dst_hoplimit(&rt->dst);
	iph->tot_len  = htons(skb->len);

	skb_dst_drop(skb);
	skb_dst_set(skb, &rt->dst);

	nf_reset(skb);

	skb->ip_summed = CHECKSUM_NONE;
	ip_select_ident(net, skb, NULL);
	ip_send_check(iph);

	ip_local_out(net, skb->sk, skb);
	return 1;

tx_error:
	kfree_skb(skb);
	return 1;
}

static int pptp_rcv_core(struct sock *sk, struct sk_buff *skb)
{
	struct pppox_sock *po = pppox_sk(sk);
	struct pptp_opt *opt = &po->proto.pptp;
	int headersize, payload_len, seq;
	__u8 *payload;
	struct pptp_gre_header *header;

	if (!(sk->sk_state & PPPOX_CONNECTED)) {
		if (sock_queue_rcv_skb(sk, skb))
			goto drop;
		return NET_RX_SUCCESS;
	}

	header = (struct pptp_gre_header *)(skb->data);
	headersize  = sizeof(*header);

	/* test if acknowledgement present */
	if (PPTP_GRE_IS_A(header->ver)) {
		__u32 ack;

		if (!pskb_may_pull(skb, headersize))
			goto drop;
		header = (struct pptp_gre_header *)(skb->data);

		/* ack in different place if S = 0 */
		ack = PPTP_GRE_IS_S(header->flags) ? header->ack : header->seq;

		ack = ntohl(ack);

		if (ack > opt->ack_recv)
			opt->ack_recv = ack;
		/* also handle sequence number wrap-around  */
		if (WRAPPED(ack, opt->ack_recv))
			opt->ack_recv = ack;
	} else {
		headersize -= sizeof(header->ack);
	}
	/* test if payload present */
	if (!PPTP_GRE_IS_S(header->flags))
		goto drop;

	payload_len = ntohs(header->payload_len);
	seq         = ntohl(header->seq);

	/* check for incomplete packet (length smaller than expected) */
	if (!pskb_may_pull(skb, headersize + payload_len))
		goto drop;

	payload = skb->data + headersize;
	/* check for expected sequence number */
	if (seq < opt->seq_recv + 1 || WRAPPED(opt->seq_recv, seq)) {
		if ((payload[0] == PPP_ALLSTATIONS) && (payload[1] == PPP_UI) &&
				(PPP_PROTOCOL(payload) == PPP_LCP) &&
				((payload[4] == PPP_LCP_ECHOREQ) || (payload[4] == PPP_LCP_ECHOREP)))
			goto allow_packet;
	} else {
		opt->seq_recv = seq;
allow_packet:
		skb_pull(skb, headersize);

		if (payload[0] == PPP_ALLSTATIONS && payload[1] == PPP_UI) {
			/* chop off address/control */
			if (skb->len < 3)
				goto drop;
			skb_pull(skb, 2);
		}

		if ((*skb->data) & 1) {
			/* protocol is compressed */
			skb_push(skb, 1)[0] = 0;
		}

		skb->ip_summed = CHECKSUM_NONE;
		skb_set_network_header(skb, skb->head-skb->data);
		ppp_input(&po->chan, skb);

		return NET_RX_SUCCESS;
	}
drop:
	kfree_skb(skb);
	return NET_RX_DROP;
}

static int pptp_rcv(struct sk_buff *skb)
{
	struct pppox_sock *po;
	struct pptp_gre_header *header;
	struct iphdr *iph;

	if (skb->pkt_type != PACKET_HOST)
		goto drop;

	if (!pskb_may_pull(skb, 12))
		goto drop;

	iph = ip_hdr(skb);

	header = (struct pptp_gre_header *)skb->data;

	if (ntohs(header->protocol) != PPTP_GRE_PROTO || /* PPTP-GRE protocol for PPTP */
		PPTP_GRE_IS_C(header->flags) ||                /* flag C should be clear */
		PPTP_GRE_IS_R(header->flags) ||                /* flag R should be clear */
		!PPTP_GRE_IS_K(header->flags) ||               /* flag K should be set */
		(header->flags&0xF) != 0)                      /* routing and recursion ctrl = 0 */
		/* if invalid, discard this packet */
		goto drop;

	po = lookup_chan(htons(header->call_id), iph->saddr);
	if (po) {
		skb_dst_drop(skb);
		nf_reset(skb);
		return sk_receive_skb(sk_pppox(po), skb, 0);
	}
drop:
	kfree_skb(skb);
	return NET_RX_DROP;
}

static int pptp_bind(struct socket *sock, struct sockaddr *uservaddr,
	int sockaddr_len)
{
	struct sock *sk = sock->sk;
	struct sockaddr_pppox *sp = (struct sockaddr_pppox *) uservaddr;
	struct pppox_sock *po = pppox_sk(sk);
	int error = 0;

	if (sockaddr_len < sizeof(struct sockaddr_pppox))
		return -EINVAL;

	lock_sock(sk);

	if (sk->sk_state & PPPOX_DEAD) {
		error = -EALREADY;
		goto out;
	}

	if (sk->sk_state & PPPOX_BOUND) {
		error = -EBUSY;
		goto out;
	}

	if (add_chan(po, &sp->sa_addr.pptp))
		error = -EBUSY;
	else
		sk->sk_state |= PPPOX_BOUND;

out:
	release_sock(sk);
	return error;
}

static int pptp_connect(struct socket *sock, struct sockaddr *uservaddr,
	int sockaddr_len, int flags)
{
	struct sock *sk = sock->sk;
	struct sockaddr_pppox *sp = (struct sockaddr_pppox *) uservaddr;
	struct pppox_sock *po = pppox_sk(sk);
	struct pptp_opt *opt = &po->proto.pptp;
	struct rtable *rt;
	struct flowi4 fl4;
	int error = 0;

	if (sockaddr_len < sizeof(struct sockaddr_pppox))
		return -EINVAL;

	if (sp->sa_protocol != PX_PROTO_PPTP)
		return -EINVAL;

	if (lookup_chan_dst(sp->sa_addr.pptp.call_id, sp->sa_addr.pptp.sin_addr.s_addr))
		return -EALREADY;

	lock_sock(sk);
	/* Check for already bound sockets */
	if (sk->sk_state & PPPOX_CONNECTED) {
		error = -EBUSY;
		goto end;
	}

	/* Check for already disconnected sockets, on attempts to disconnect */
	if (sk->sk_state & PPPOX_DEAD) {
		error = -EALREADY;
		goto end;
	}

	if (!opt->src_addr.sin_addr.s_addr || !sp->sa_addr.pptp.sin_addr.s_addr) {
		error = -EINVAL;
		goto end;
	}

	po->chan.private = sk;
	po->chan.ops = &pptp_chan_ops;

	rt = ip_route_output_ports(sock_net(sk), &fl4, sk,
				   opt->dst_addr.sin_addr.s_addr,
				   opt->src_addr.sin_addr.s_addr,
				   0, 0,
				   IPPROTO_GRE, RT_CONN_FLAGS(sk), 0);
	if (IS_ERR(rt)) {
		error = -EHOSTUNREACH;
		goto end;
	}
	sk_setup_caps(sk, &rt->dst);

	po->chan.mtu = dst_mtu(&rt->dst);
	if (!po->chan.mtu)
		po->chan.mtu = PPP_MRU;
	ip_rt_put(rt);
	po->chan.mtu -= PPTP_HEADER_OVERHEAD;

	po->chan.hdrlen = 2 + sizeof(struct pptp_gre_header);
	error = ppp_register_channel(&po->chan);
	if (error) {
		pr_err("PPTP: failed to register PPP channel (%d)\n", error);
		goto end;
	}

	opt->dst_addr = sp->sa_addr.pptp;
	sk->sk_state |= PPPOX_CONNECTED;

 end:
	release_sock(sk);
	return error;
}

static int pptp_getname(struct socket *sock, struct sockaddr *uaddr,
	int *usockaddr_len, int peer)
{
	int len = sizeof(struct sockaddr_pppox);
	struct sockaddr_pppox sp;

	memset(&sp.sa_addr, 0, sizeof(sp.sa_addr));

	sp.sa_family    = AF_PPPOX;
	sp.sa_protocol  = PX_PROTO_PPTP;
	sp.sa_addr.pptp = pppox_sk(sock->sk)->proto.pptp.src_addr;

	memcpy(uaddr, &sp, len);

	*usockaddr_len = len;

	return 0;
}

static int pptp_release(struct socket *sock)
{
	struct sock *sk = sock->sk;
	struct pppox_sock *po;
	struct pptp_opt *opt;
	int error = 0;

	if (!sk)
		return 0;

	lock_sock(sk);

	if (sock_flag(sk, SOCK_DEAD)) {
		release_sock(sk);
		return -EBADF;
	}

	po = pppox_sk(sk);
	opt = &po->proto.pptp;
	del_chan(po);

	pppox_unbind_sock(sk);
	sk->sk_state = PPPOX_DEAD;

	sock_orphan(sk);
	sock->sk = NULL;

	release_sock(sk);
	sock_put(sk);

	return error;
}

static void pptp_sock_destruct(struct sock *sk)
{
	if (!(sk->sk_state & PPPOX_DEAD)) {
		del_chan(pppox_sk(sk));
		pppox_unbind_sock(sk);
	}
	skb_queue_purge(&sk->sk_receive_queue);
}

static int pptp_create(struct net *net, struct socket *sock, int kern)
{
	int error = -ENOMEM;
	struct sock *sk;
	struct pppox_sock *po;
	struct pptp_opt *opt;

	sk = sk_alloc(net, PF_PPPOX, GFP_KERNEL, &pptp_sk_proto, kern);
	if (!sk)
		goto out;

	sock_init_data(sock, sk);

	sock->state = SS_UNCONNECTED;
	sock->ops   = &pptp_ops;

	sk->sk_backlog_rcv = pptp_rcv_core;
	sk->sk_state       = PPPOX_NONE;
	sk->sk_type        = SOCK_STREAM;
	sk->sk_family      = PF_PPPOX;
	sk->sk_protocol    = PX_PROTO_PPTP;
	sk->sk_destruct    = pptp_sock_destruct;

	po = pppox_sk(sk);
	opt = &po->proto.pptp;

	opt->seq_sent = 0; opt->seq_recv = 0xffffffff;
	opt->ack_recv = 0; opt->ack_sent = 0xffffffff;

	error = 0;
out:
	return error;
}

static int pptp_ppp_ioctl(struct ppp_channel *chan, unsigned int cmd,
	unsigned long arg)
{
	struct sock *sk = (struct sock *) chan->private;
	struct pppox_sock *po = pppox_sk(sk);
	struct pptp_opt *opt = &po->proto.pptp;
	void __user *argp = (void __user *)arg;
	int __user *p = argp;
	int err, val;

	err = -EFAULT;
	switch (cmd) {
	case PPPIOCGFLAGS:
		val = opt->ppp_flags;
		if (put_user(val, p))
			break;
		err = 0;
		break;
	case PPPIOCSFLAGS:
		if (get_user(val, p))
			break;
		opt->ppp_flags = val & ~SC_RCV_BITS;
		err = 0;
		break;
	default:
		err = -ENOTTY;
	}

	return err;
}

static const struct ppp_channel_ops pptp_chan_ops = {
	.start_xmit = pptp_xmit,
	.ioctl      = pptp_ppp_ioctl,
};

static struct proto pptp_sk_proto __read_mostly = {
	.name     = "PPTP",
	.owner    = THIS_MODULE,
	.obj_size = sizeof(struct pppox_sock),
};

static const struct proto_ops pptp_ops = {
	.family     = AF_PPPOX,
	.owner      = THIS_MODULE,
	.release    = pptp_release,
	.bind       = pptp_bind,
	.connect    = pptp_connect,
	.socketpair = sock_no_socketpair,
	.accept     = sock_no_accept,
	.getname    = pptp_getname,
	.poll       = sock_no_poll,
	.listen     = sock_no_listen,
	.shutdown   = sock_no_shutdown,
	.setsockopt = sock_no_setsockopt,
	.getsockopt = sock_no_getsockopt,
	.sendmsg    = sock_no_sendmsg,
	.recvmsg    = sock_no_recvmsg,
	.mmap       = sock_no_mmap,
	.ioctl      = pppox_ioctl,
};

static const struct pppox_proto pppox_pptp_proto = {
	.create = pptp_create,
	.owner  = THIS_MODULE,
};

static const struct gre_protocol gre_pptp_protocol = {
	.handler = pptp_rcv,
};

static int __init pptp_init_module(void)
{
	int err = 0;
	pr_info("PPTP driver version " PPTP_DRIVER_VERSION "\n");

	callid_sock = vzalloc((MAX_CALLID + 1) * sizeof(void *));
	if (!callid_sock)
		return -ENOMEM;

	err = gre_add_protocol(&gre_pptp_protocol, GREPROTO_PPTP);
	if (err) {
		pr_err("PPTP: can't add gre protocol\n");
		goto out_mem_free;
	}

	err = proto_register(&pptp_sk_proto, 0);
	if (err) {
		pr_err("PPTP: can't register sk_proto\n");
		goto out_gre_del_protocol;
	}

	err = register_pppox_proto(PX_PROTO_PPTP, &pppox_pptp_proto);
	if (err) {
		pr_err("PPTP: can't register pppox_proto\n");
		goto out_unregister_sk_proto;
	}

	return 0;

out_unregister_sk_proto:
	proto_unregister(&pptp_sk_proto);
out_gre_del_protocol:
	gre_del_protocol(&gre_pptp_protocol, GREPROTO_PPTP);
out_mem_free:
	vfree(callid_sock);

	return err;
}

static void __exit pptp_exit_module(void)
{
	unregister_pppox_proto(PX_PROTO_PPTP);
	proto_unregister(&pptp_sk_proto);
	gre_del_protocol(&gre_pptp_protocol, GREPROTO_PPTP);
	vfree(callid_sock);
}

module_init(pptp_init_module);
module_exit(pptp_exit_module);

MODULE_DESCRIPTION("Point-to-Point Tunneling Protocol");
MODULE_AUTHOR("D. Kozlov (xeb@mail.ru)");
MODULE_LICENSE("GPL");
MODULE_ALIAS_NET_PF_PROTO(PF_PPPOX, PX_PROTO_PPTP);
Commit	Line	Data
00959ade DK	1	/*
	2	* Point-to-Point Tunneling Protocol for Linux
	3	*
	4	* Authors: Dmitry Kozlov <xeb@mail.ru>
	5	*
	6	* This program is free software; you can redistribute it and/or
	7	* modify it under the terms of the GNU General Public License
	8	* as published by the Free Software Foundation; either version
	9	* 2 of the License, or (at your option) any later version.
	10	*
	11	*/
	12
	13	#include <linux/string.h>
	14	#include <linux/module.h>
	15	#include <linux/kernel.h>
	16	#include <linux/slab.h>
	17	#include <linux/errno.h>
	18	#include <linux/netdevice.h>
	19	#include <linux/net.h>
	20	#include <linux/skbuff.h>
	21	#include <linux/vmalloc.h>
	22	#include <linux/init.h>
	23	#include <linux/ppp_channel.h>
	24	#include <linux/ppp_defs.h>
	25	#include <linux/if_pppox.h>
bf7daebb	26	#include <linux/ppp-ioctl.h>
00959ade DK	27	#include <linux/notifier.h>
	28	#include <linux/file.h>
	29	#include <linux/in.h>
	30	#include <linux/ip.h>
00959ade DK	31	#include <linux/rcupdate.h>
	32	#include <linux/spinlock.h>
	33
	34	#include <net/sock.h>
	35	#include <net/protocol.h>
	36	#include <net/ip.h>
	37	#include <net/icmp.h>
	38	#include <net/route.h>
	39	#include <net/gre.h>
	40
	41	#include <linux/uaccess.h>
	42
	43	#define PPTP_DRIVER_VERSION "0.8.5"
	44
	45	#define MAX_CALLID 65535
	46
	47	static DECLARE_BITMAP(callid_bitmap, MAX_CALLID + 1);
469230d1	48	static struct pppox_sock __rcu **callid_sock;
00959ade DK	49
	50	static DEFINE_SPINLOCK(chan_lock);
	51
	52	static struct proto pptp_sk_proto __read_mostly;
756e64a0	53	static const struct ppp_channel_ops pptp_chan_ops;
00959ade DK	54	static const struct proto_ops pptp_ops;
	55
	56	#define PPP_LCP_ECHOREQ 0x09
	57	#define PPP_LCP_ECHOREP 0x0A
	58	#define SC_RCV_BITS (SC_RCV_B7_1\|SC_RCV_B7_0\|SC_RCV_ODDP\|SC_RCV_EVNP)
	59
	60	#define MISSING_WINDOW 20
	61	#define WRAPPED(curseq, lastseq)\
	62	((((curseq) & 0xffffff00) == 0) &&\
	63	(((lastseq) & 0xffffff00) == 0xffffff00))
	64
	65	#define PPTP_GRE_PROTO 0x880B
	66	#define PPTP_GRE_VER 0x1
	67
	68	#define PPTP_GRE_FLAG_C 0x80
	69	#define PPTP_GRE_FLAG_R 0x40
	70	#define PPTP_GRE_FLAG_K 0x20
	71	#define PPTP_GRE_FLAG_S 0x10
	72	#define PPTP_GRE_FLAG_A 0x80
	73
	74	#define PPTP_GRE_IS_C(f) ((f)&PPTP_GRE_FLAG_C)
	75	#define PPTP_GRE_IS_R(f) ((f)&PPTP_GRE_FLAG_R)
	76	#define PPTP_GRE_IS_K(f) ((f)&PPTP_GRE_FLAG_K)
	77	#define PPTP_GRE_IS_S(f) ((f)&PPTP_GRE_FLAG_S)
	78	#define PPTP_GRE_IS_A(f) ((f)&PPTP_GRE_FLAG_A)
	79
	80	#define PPTP_HEADER_OVERHEAD (2+sizeof(struct pptp_gre_header))
	81	struct pptp_gre_header {
	82	u8 flags;
	83	u8 ver;
ebd8b934	84	__be16 protocol;
	85	__be16 payload_len;
	86	__be16 call_id;
	87	__be32 seq;
	88	__be32 ack;
00959ade DK	89	} __packed;
	90
	91	static struct pppox_sock *lookup_chan(u16 call_id, __be32 s_addr)
	92	{
	93	struct pppox_sock *sock;
	94	struct pptp_opt *opt;
	95
	96	rcu_read_lock();
	97	sock = rcu_dereference(callid_sock[call_id]);
	98	if (sock) {
	99	opt = &sock->proto.pptp;
	100	if (opt->dst_addr.sin_addr.s_addr != s_addr)
	101	sock = NULL;
	102	else
	103	sock_hold(sk_pppox(sock));
	104	}
	105	rcu_read_unlock();
	106
	107	return sock;
	108	}
	109
	110	static int lookup_chan_dst(u16 call_id, __be32 d_addr)
	111	{
	112	struct pppox_sock *sock;
	113	struct pptp_opt *opt;
	114	int i;
	115
	116	rcu_read_lock();
99427747 AM	117	i = 1;
99427747 AM	118	for_each_set_bit_from(i, callid_bitmap, MAX_CALLID) {
00959ade DK	119	sock = rcu_dereference(callid_sock[i]);
	120	if (!sock)
	121	continue;
	122	opt = &sock->proto.pptp;
	123	if (opt->dst_addr.call_id == call_id &&
	124	opt->dst_addr.sin_addr.s_addr == d_addr)
	125	break;
	126	}
	127	rcu_read_unlock();
	128
	129	return i < MAX_CALLID;
	130	}
	131
9a368aff HFS	132	static int add_chan(struct pppox_sock *sock,
9a368aff HFS	133	struct pptp_addr *sa)
00959ade DK	134	{
	135	static int call_id;
	136
	137	spin_lock(&chan_lock);
9a368aff	138	if (!sa->call_id) {
00959ade DK	139	call_id = find_next_zero_bit(callid_bitmap, MAX_CALLID, call_id + 1);
	140	if (call_id == MAX_CALLID) {
	141	call_id = find_next_zero_bit(callid_bitmap, MAX_CALLID, 1);
	142	if (call_id == MAX_CALLID)
	143	goto out_err;
	144	}
9a368aff HFS	145	sa->call_id = call_id;
9a368aff HFS	146	} else if (test_bit(sa->call_id, callid_bitmap)) {
00959ade	147	goto out_err;
9a368aff	148	}
00959ade	149
9a368aff HFS	150	sock->proto.pptp.src_addr = *sa;
	151	set_bit(sa->call_id, callid_bitmap);
	152	rcu_assign_pointer(callid_sock[sa->call_id], sock);
00959ade DK	153	spin_unlock(&chan_lock);
	154
	155	return 0;
	156
	157	out_err:
	158	spin_unlock(&chan_lock);
	159	return -1;
	160	}
	161
	162	static void del_chan(struct pppox_sock *sock)
	163	{
	164	spin_lock(&chan_lock);
	165	clear_bit(sock->proto.pptp.src_addr.call_id, callid_bitmap);
2cfa5a04	166	RCU_INIT_POINTER(callid_sock[sock->proto.pptp.src_addr.call_id], NULL);
00959ade DK	167	spin_unlock(&chan_lock);
	168	synchronize_rcu();
	169	}
	170
	171	static int pptp_xmit(struct ppp_channel chan, struct sk_buff skb)
	172	{
	173	struct sock sk = (struct sock ) chan->private;
	174	struct pppox_sock *po = pppox_sk(sk);
a7093fef	175	struct net *net = sock_net(sk);
00959ade DK	176	struct pptp_opt *opt = &po->proto.pptp;
	177	struct pptp_gre_header *hdr;
	178	unsigned int header_len = sizeof(*hdr);
31e4543d	179	struct flowi4 fl4;
00959ade DK	180	int islcp;
	181	int len;
	182	unsigned char *data;
	183	__u32 seq_recv;
	184
	185
	186	struct rtable *rt;
	187	struct net_device *tdev;
	188	struct iphdr *iph;
	189	int max_headroom;
	190
	191	if (sk_pppox(po)->sk_state & PPPOX_DEAD)
	192	goto tx_error;
	193
a7093fef	194	rt = ip_route_output_ports(net, &fl4, NULL,
78fbfd8a DM	195	opt->dst_addr.sin_addr.s_addr,
	196	opt->src_addr.sin_addr.s_addr,
	197	0, 0, IPPROTO_GRE,
	198	RT_TOS(0), 0);
	199	if (IS_ERR(rt))
	200	goto tx_error;
	201
00959ade DK	202	tdev = rt->dst.dev;
	203
	204	max_headroom = LL_RESERVED_SPACE(tdev) + sizeof(iph) + sizeof(hdr) + 2;
	205
	206	if (skb_headroom(skb) < max_headroom \|\| skb_cloned(skb) \|\| skb_shared(skb)) {
	207	struct sk_buff *new_skb = skb_realloc_headroom(skb, max_headroom);
	208	if (!new_skb) {
	209	ip_rt_put(rt);
	210	goto tx_error;
	211	}
	212	if (skb->sk)
	213	skb_set_owner_w(new_skb, skb->sk);
968d7018	214	consume_skb(skb);
00959ade DK	215	skb = new_skb;
	216	}
	217
	218	data = skb->data;
	219	islcp = ((data[0] << 8) + data[1]) == PPP_LCP && 1 <= data[2] && data[2] <= 7;
	220
	221	/* compress protocol field */
	222	if ((opt->ppp_flags & SC_COMP_PROT) && data[0] == 0 && !islcp)
	223	skb_pull(skb, 1);
	224
	225	/* Put in the address/control bytes if necessary */
	226	if ((opt->ppp_flags & SC_COMP_AC) == 0 \|\| islcp) {
	227	data = skb_push(skb, 2);
	228	data[0] = PPP_ALLSTATIONS;
	229	data[1] = PPP_UI;
	230	}
	231
	232	len = skb->len;
	233
	234	seq_recv = opt->seq_recv;
	235
	236	if (opt->ack_sent == seq_recv)
	237	header_len -= sizeof(hdr->ack);
	238
	239	/* Push down and install GRE header */
	240	skb_push(skb, header_len);
	241	hdr = (struct pptp_gre_header *)(skb->data);
	242
	243	hdr->flags = PPTP_GRE_FLAG_K;
	244	hdr->ver = PPTP_GRE_VER;
	245	hdr->protocol = htons(PPTP_GRE_PROTO);
	246	hdr->call_id = htons(opt->dst_addr.call_id);
	247
	248	hdr->flags \|= PPTP_GRE_FLAG_S;
	249	hdr->seq = htonl(++opt->seq_sent);
	250	if (opt->ack_sent != seq_recv) {
	251	/* send ack with this message */
	252	hdr->ver \|= PPTP_GRE_FLAG_A;
	253	hdr->ack = htonl(seq_recv);
	254	opt->ack_sent = seq_recv;
	255	}
	256	hdr->payload_len = htons(len);
	257
	258	/* Push down and install the IP header. */
	259
	260	skb_reset_transport_header(skb);
	261	skb_push(skb, sizeof(*iph));
	262	skb_reset_network_header(skb);
	263	memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt));
	264	IPCB(skb)->flags &= ~(IPSKB_XFRM_TUNNEL_SIZE \| IPSKB_XFRM_TRANSFORMED \| IPSKB_REROUTED);
	265
	266	iph = ip_hdr(skb);
	267	iph->version = 4;
	268	iph->ihl = sizeof(struct iphdr) >> 2;
	269	if (ip_dont_fragment(sk, &rt->dst))
	270	iph->frag_off = htons(IP_DF);
	271	else
	272	iph->frag_off = 0;
	273	iph->protocol = IPPROTO_GRE;
	274	iph->tos = 0;
28c90da0 DM	275	iph->daddr = fl4.daddr;
28c90da0 DM	276	iph->saddr = fl4.saddr;
323e126f	277	iph->ttl = ip4_dst_hoplimit(&rt->dst);
00959ade DK	278	iph->tot_len = htons(skb->len);
	279
	280	skb_dst_drop(skb);
	281	skb_dst_set(skb, &rt->dst);
	282
	283	nf_reset(skb);
	284
	285	skb->ip_summed = CHECKSUM_NONE;
a7093fef	286	ip_select_ident(net, skb, NULL);
00959ade DK	287	ip_send_check(iph);
00959ade DK	288
33224b16	289	ip_local_out(net, skb->sk, skb);
8bae8bd6	290	return 1;
00959ade DK	291
00959ade DK	292	tx_error:
8bae8bd6	293	kfree_skb(skb);
00959ade DK	294	return 1;
	295	}
	296
	297	static int pptp_rcv_core(struct sock sk, struct sk_buff skb)
	298	{
	299	struct pppox_sock *po = pppox_sk(sk);
	300	struct pptp_opt *opt = &po->proto.pptp;
	301	int headersize, payload_len, seq;
	302	__u8 *payload;
	303	struct pptp_gre_header *header;
	304
	305	if (!(sk->sk_state & PPPOX_CONNECTED)) {
	306	if (sock_queue_rcv_skb(sk, skb))
	307	goto drop;
	308	return NET_RX_SUCCESS;
	309	}
	310
	311	header = (struct pptp_gre_header *)(skb->data);
4ea2739e	312	headersize = sizeof(*header);
00959ade DK	313
	314	/* test if acknowledgement present */
	315	if (PPTP_GRE_IS_A(header->ver)) {
4ea2739e ED	316	__u32 ack;
	317
	318	if (!pskb_may_pull(skb, headersize))
	319	goto drop;
	320	header = (struct pptp_gre_header *)(skb->data);
	321
	322	/* ack in different place if S = 0 */
	323	ack = PPTP_GRE_IS_S(header->flags) ? header->ack : header->seq;
00959ade DK	324
	325	ack = ntohl(ack);
	326
	327	if (ack > opt->ack_recv)
	328	opt->ack_recv = ack;
	329	/* also handle sequence number wrap-around */
	330	if (WRAPPED(ack, opt->ack_recv))
	331	opt->ack_recv = ack;
4ea2739e ED	332	} else {
4ea2739e ED	333	headersize -= sizeof(header->ack);
00959ade	334	}
00959ade DK	335	/* test if payload present */
	336	if (!PPTP_GRE_IS_S(header->flags))
	337	goto drop;
	338
00959ade DK	339	payload_len = ntohs(header->payload_len);
	340	seq = ntohl(header->seq);
	341
00959ade	342	/* check for incomplete packet (length smaller than expected) */
4ea2739e	343	if (!pskb_may_pull(skb, headersize + payload_len))
00959ade DK	344	goto drop;
	345
	346	payload = skb->data + headersize;
	347	/* check for expected sequence number */
	348	if (seq < opt->seq_recv + 1 \|\| WRAPPED(opt->seq_recv, seq)) {
	349	if ((payload[0] == PPP_ALLSTATIONS) && (payload[1] == PPP_UI) &&
	350	(PPP_PROTOCOL(payload) == PPP_LCP) &&
	351	((payload[4] == PPP_LCP_ECHOREQ) \|\| (payload[4] == PPP_LCP_ECHOREP)))
	352	goto allow_packet;
	353	} else {
	354	opt->seq_recv = seq;
	355	allow_packet:
	356	skb_pull(skb, headersize);
	357
	358	if (payload[0] == PPP_ALLSTATIONS && payload[1] == PPP_UI) {
	359	/* chop off address/control */
	360	if (skb->len < 3)
	361	goto drop;
	362	skb_pull(skb, 2);
	363	}
	364
	365	if ((*skb->data) & 1) {
	366	/* protocol is compressed */
	367	skb_push(skb, 1)[0] = 0;
	368	}
	369
	370	skb->ip_summed = CHECKSUM_NONE;
	371	skb_set_network_header(skb, skb->head-skb->data);
	372	ppp_input(&po->chan, skb);
	373
	374	return NET_RX_SUCCESS;
	375	}
	376	drop:
	377	kfree_skb(skb);
	378	return NET_RX_DROP;
	379	}
	380
	381	static int pptp_rcv(struct sk_buff *skb)
	382	{
	383	struct pppox_sock *po;
	384	struct pptp_gre_header *header;
	385	struct iphdr *iph;
	386
	387	if (skb->pkt_type != PACKET_HOST)
	388	goto drop;
	389
	390	if (!pskb_may_pull(skb, 12))
	391	goto drop;
	392
	393	iph = ip_hdr(skb);
	394
	395	header = (struct pptp_gre_header *)skb->data;
	396
	397	if (ntohs(header->protocol) != PPTP_GRE_PROTO \|\| /* PPTP-GRE protocol for PPTP */
	398	PPTP_GRE_IS_C(header->flags) \|\| /* flag C should be clear */
	399	PPTP_GRE_IS_R(header->flags) \|\| /* flag R should be clear */
	400	!PPTP_GRE_IS_K(header->flags) \|\| /* flag K should be set */
	401	(header->flags&0xF) != 0) /* routing and recursion ctrl = 0 */
	402	/* if invalid, discard this packet */
	403	goto drop;
	404
	405	po = lookup_chan(htons(header->call_id), iph->saddr);
	406	if (po) {
	407	skb_dst_drop(skb);
408	nf_reset(skb);
409	return sk_receive_skb(sk_pppox(po), skb, 0);
410	}
411	drop:
412	kfree_skb(skb);
413	return NET_RX_DROP;
414	}
415
416	static int pptp_bind(struct socket sock, struct sockaddr uservaddr,
417	int sockaddr_len)
418	{
419	struct sock *sk = sock->sk;
420	struct sockaddr_pppox sp = (struct sockaddr_pppox ) uservaddr;
421	struct pppox_sock *po = pppox_sk(sk);
00959ade DK	422	int error = 0;
00959ade DK	423
09ccfd23 WC	424	if (sockaddr_len < sizeof(struct sockaddr_pppox))
	425	return -EINVAL;
	426
00959ade DK	427	lock_sock(sk);
00959ade DK	428
9a368aff HFS	429	if (sk->sk_state & PPPOX_DEAD) {
	430	error = -EALREADY;
	431	goto out;
	432	}
	433
	434	if (sk->sk_state & PPPOX_BOUND) {
00959ade	435	error = -EBUSY;
9a368aff HFS	436	goto out;
	437	}
	438
	439	if (add_chan(po, &sp->sa_addr.pptp))
	440	error = -EBUSY;
	441	else
	442	sk->sk_state \|= PPPOX_BOUND;
00959ade	443
9a368aff	444	out:
00959ade DK	445	release_sock(sk);
	446	return error;
	447	}
	448
	449	static int pptp_connect(struct socket sock, struct sockaddr uservaddr,
	450	int sockaddr_len, int flags)
	451	{
	452	struct sock *sk = sock->sk;
	453	struct sockaddr_pppox sp = (struct sockaddr_pppox ) uservaddr;
	454	struct pppox_sock *po = pppox_sk(sk);
	455	struct pptp_opt *opt = &po->proto.pptp;
	456	struct rtable *rt;
31e4543d	457	struct flowi4 fl4;
00959ade DK	458	int error = 0;
00959ade DK	459
09ccfd23 WC	460	if (sockaddr_len < sizeof(struct sockaddr_pppox))
	461	return -EINVAL;
	462
00959ade DK	463	if (sp->sa_protocol != PX_PROTO_PPTP)
	464	return -EINVAL;
	465
	466	if (lookup_chan_dst(sp->sa_addr.pptp.call_id, sp->sa_addr.pptp.sin_addr.s_addr))
	467	return -EALREADY;
	468
	469	lock_sock(sk);
	470	/* Check for already bound sockets */
	471	if (sk->sk_state & PPPOX_CONNECTED) {
	472	error = -EBUSY;
	473	goto end;
	474	}
	475
	476	/* Check for already disconnected sockets, on attempts to disconnect */
	477	if (sk->sk_state & PPPOX_DEAD) {
	478	error = -EALREADY;
	479	goto end;
	480	}
	481
	482	if (!opt->src_addr.sin_addr.s_addr \|\| !sp->sa_addr.pptp.sin_addr.s_addr) {
	483	error = -EINVAL;
	484	goto end;
	485	}
	486
	487	po->chan.private = sk;
	488	po->chan.ops = &pptp_chan_ops;
	489
08252b32	490	rt = ip_route_output_ports(sock_net(sk), &fl4, sk,
78fbfd8a DM	491	opt->dst_addr.sin_addr.s_addr,
	492	opt->src_addr.sin_addr.s_addr,
	493	0, 0,
	494	IPPROTO_GRE, RT_CONN_FLAGS(sk), 0);
	495	if (IS_ERR(rt)) {
	496	error = -EHOSTUNREACH;
	497	goto end;
00959ade	498	}
78fbfd8a DM	499	sk_setup_caps(sk, &rt->dst);
78fbfd8a DM	500
00959ade DK	501	po->chan.mtu = dst_mtu(&rt->dst);
00959ade DK	502	if (!po->chan.mtu)
bf7daebb	503	po->chan.mtu = PPP_MRU;
00959ade DK	504	ip_rt_put(rt);
	505	po->chan.mtu -= PPTP_HEADER_OVERHEAD;
	506
	507	po->chan.hdrlen = 2 + sizeof(struct pptp_gre_header);
	508	error = ppp_register_channel(&po->chan);
	509	if (error) {
	510	pr_err("PPTP: failed to register PPP channel (%d)\n", error);
	511	goto end;
	512	}
	513
	514	opt->dst_addr = sp->sa_addr.pptp;
9a368aff	515	sk->sk_state \|= PPPOX_CONNECTED;
00959ade DK	516
	517	end:
	518	release_sock(sk);
	519	return error;
	520	}
	521
	522	static int pptp_getname(struct socket sock, struct sockaddr uaddr,
	523	int *usockaddr_len, int peer)
	524	{
	525	int len = sizeof(struct sockaddr_pppox);
	526	struct sockaddr_pppox sp;
	527
a5f6fc28 MK	528	memset(&sp.sa_addr, 0, sizeof(sp.sa_addr));
	529
	530	sp.sa_family = AF_PPPOX;
00959ade DK	531	sp.sa_protocol = PX_PROTO_PPTP;
	532	sp.sa_addr.pptp = pppox_sk(sock->sk)->proto.pptp.src_addr;
	533
	534	memcpy(uaddr, &sp, len);
	535
	536	*usockaddr_len = len;
	537
	538	return 0;
	539	}
	540
	541	static int pptp_release(struct socket *sock)
	542	{
	543	struct sock *sk = sock->sk;
	544	struct pppox_sock *po;
	545	struct pptp_opt *opt;
	546	int error = 0;
	547
	548	if (!sk)
	549	return 0;
	550
	551	lock_sock(sk);
	552
	553	if (sock_flag(sk, SOCK_DEAD)) {
	554	release_sock(sk);
	555	return -EBADF;
	556	}
	557
	558	po = pppox_sk(sk);
	559	opt = &po->proto.pptp;
	560	del_chan(po);
	561
	562	pppox_unbind_sock(sk);
	563	sk->sk_state = PPPOX_DEAD;
	564
	565	sock_orphan(sk);
	566	sock->sk = NULL;
	567
	568	release_sock(sk);
	569	sock_put(sk);
	570
	571	return error;
	572	}
	573
	574	static void pptp_sock_destruct(struct sock *sk)
	575	{
	576	if (!(sk->sk_state & PPPOX_DEAD)) {
	577	del_chan(pppox_sk(sk));
	578	pppox_unbind_sock(sk);
	579	}
	580	skb_queue_purge(&sk->sk_receive_queue);
	581	}
	582
11aa9c28	583	static int pptp_create(struct net net, struct socket sock, int kern)
00959ade DK	584	{
	585	int error = -ENOMEM;
	586	struct sock *sk;
	587	struct pppox_sock *po;
	588	struct pptp_opt *opt;
	589
11aa9c28	590	sk = sk_alloc(net, PF_PPPOX, GFP_KERNEL, &pptp_sk_proto, kern);
00959ade DK	591	if (!sk)
	592	goto out;
	593
	594	sock_init_data(sock, sk);
	595
	596	sock->state = SS_UNCONNECTED;
	597	sock->ops = &pptp_ops;
	598
	599	sk->sk_backlog_rcv = pptp_rcv_core;
	600	sk->sk_state = PPPOX_NONE;
	601	sk->sk_type = SOCK_STREAM;
	602	sk->sk_family = PF_PPPOX;
	603	sk->sk_protocol = PX_PROTO_PPTP;
	604	sk->sk_destruct = pptp_sock_destruct;
	605
	606	po = pppox_sk(sk);
	607	opt = &po->proto.pptp;
	608
91dce7dd BP	609	opt->seq_sent = 0; opt->seq_recv = 0xffffffff;
91dce7dd BP	610	opt->ack_recv = 0; opt->ack_sent = 0xffffffff;
00959ade DK	611
	612	error = 0;
	613	out:
	614	return error;
	615	}
	616
	617	static int pptp_ppp_ioctl(struct ppp_channel *chan, unsigned int cmd,
	618	unsigned long arg)
	619	{
	620	struct sock sk = (struct sock ) chan->private;
	621	struct pppox_sock *po = pppox_sk(sk);
	622	struct pptp_opt *opt = &po->proto.pptp;
	623	void __user argp = (void __user )arg;
	624	int __user *p = argp;
	625	int err, val;
	626
	627	err = -EFAULT;
	628	switch (cmd) {
	629	case PPPIOCGFLAGS:
	630	val = opt->ppp_flags;
	631	if (put_user(val, p))
	632	break;
	633	err = 0;
	634	break;
	635	case PPPIOCSFLAGS:
	636	if (get_user(val, p))
	637	break;
	638	opt->ppp_flags = val & ~SC_RCV_BITS;
	639	err = 0;
	640	break;
	641	default:
	642	err = -ENOTTY;
	643	}
	644
	645	return err;
	646	}
	647
756e64a0	648	static const struct ppp_channel_ops pptp_chan_ops = {
00959ade DK	649	.start_xmit = pptp_xmit,
	650	.ioctl = pptp_ppp_ioctl,
	651	};
	652
	653	static struct proto pptp_sk_proto __read_mostly = {
	654	.name = "PPTP",
	655	.owner = THIS_MODULE,
	656	.obj_size = sizeof(struct pppox_sock),
	657	};
	658
	659	static const struct proto_ops pptp_ops = {
	660	.family = AF_PPPOX,
	661	.owner = THIS_MODULE,
	662	.release = pptp_release,
	663	.bind = pptp_bind,
	664	.connect = pptp_connect,
	665	.socketpair = sock_no_socketpair,
	666	.accept = sock_no_accept,
	667	.getname = pptp_getname,
	668	.poll = sock_no_poll,
	669	.listen = sock_no_listen,
	670	.shutdown = sock_no_shutdown,
	671	.setsockopt = sock_no_setsockopt,
	672	.getsockopt = sock_no_getsockopt,
	673	.sendmsg = sock_no_sendmsg,
	674	.recvmsg = sock_no_recvmsg,
	675	.mmap = sock_no_mmap,
	676	.ioctl = pppox_ioctl,
	677	};
	678
756e64a0	679	static const struct pppox_proto pppox_pptp_proto = {
00959ade DK	680	.create = pptp_create,
	681	.owner = THIS_MODULE,
	682	};
	683
756e64a0	684	static const struct gre_protocol gre_pptp_protocol = {
00959ade DK	685	.handler = pptp_rcv,
	686	};
	687
	688	static int __init pptp_init_module(void)
	689	{
	690	int err = 0;
	691	pr_info("PPTP driver version " PPTP_DRIVER_VERSION "\n");
	692
89bf67f1	693	callid_sock = vzalloc((MAX_CALLID + 1) * sizeof(void *));
e404decb	694	if (!callid_sock)
00959ade	695	return -ENOMEM;
00959ade DK	696
	697	err = gre_add_protocol(&gre_pptp_protocol, GREPROTO_PPTP);
	698	if (err) {
	699	pr_err("PPTP: can't add gre protocol\n");
	700	goto out_mem_free;
	701	}
	702
	703	err = proto_register(&pptp_sk_proto, 0);
	704	if (err) {
	705	pr_err("PPTP: can't register sk_proto\n");
	706	goto out_gre_del_protocol;
	707	}
	708
	709	err = register_pppox_proto(PX_PROTO_PPTP, &pppox_pptp_proto);
	710	if (err) {
	711	pr_err("PPTP: can't register pppox_proto\n");
	712	goto out_unregister_sk_proto;
	713	}
	714
	715	return 0;
	716
	717	out_unregister_sk_proto:
	718	proto_unregister(&pptp_sk_proto);
	719	out_gre_del_protocol:
	720	gre_del_protocol(&gre_pptp_protocol, GREPROTO_PPTP);
	721	out_mem_free:
	722	vfree(callid_sock);
	723
	724	return err;
	725	}
	726
	727	static void __exit pptp_exit_module(void)
	728	{
	729	unregister_pppox_proto(PX_PROTO_PPTP);
	730	proto_unregister(&pptp_sk_proto);
	731	gre_del_protocol(&gre_pptp_protocol, GREPROTO_PPTP);
	732	vfree(callid_sock);
	733	}
	734
	735	module_init(pptp_init_module);
	736	module_exit(pptp_exit_module);
	737
	738	MODULE_DESCRIPTION("Point-to-Point Tunneling Protocol");
	739	MODULE_AUTHOR("D. Kozlov (xeb@mail.ru)");
	740	MODULE_LICENSE("GPL");
681b4d88	741	MODULE_ALIAS_NET_PF_PROTO(PF_PPPOX, PX_PROTO_PPTP);