[net-next-2.6.git] / net / phonet / af_phonet.c

/*
 * File: af_phonet.c
 *
 * Phonet protocols family
 *
 * Copyright (C) 2008 Nokia Corporation.
 *
 * Contact: Remi Denis-Courmont <remi.denis-courmont@nokia.com>
 * Original author: Sakari Ailus <sakari.ailus@nokia.com>
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * version 2 as published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
 * 02110-1301 USA
 */

#include <linux/kernel.h>
#include <linux/module.h>
#include <asm/unaligned.h>
#include <net/sock.h>

#include <linux/if_phonet.h>
#include <linux/phonet.h>
#include <net/phonet/phonet.h>
#include <net/phonet/pn_dev.h>

static struct net_proto_family phonet_proto_family;
static struct phonet_protocol *phonet_proto_get(int protocol);
static inline void phonet_proto_put(struct phonet_protocol *pp);

/* protocol family functions */

static int pn_socket_create(struct net *net, struct socket *sock, int protocol)
{
	struct sock *sk;
	struct pn_sock *pn;
	struct phonet_protocol *pnp;
	int err;

	if (net != &init_net)
		return -EAFNOSUPPORT;

	if (!capable(CAP_SYS_ADMIN))
		return -EPERM;

	if (protocol == 0) {
		/* Default protocol selection */
		switch (sock->type) {
		case SOCK_DGRAM:
			protocol = PN_PROTO_PHONET;
			break;
		case SOCK_SEQPACKET:
			protocol = PN_PROTO_PIPE;
			break;
		default:
			return -EPROTONOSUPPORT;
		}
	}

	pnp = phonet_proto_get(protocol);
#ifdef CONFIG_KMOD
	if (pnp == NULL &&
	    request_module("net-pf-%d-proto-%d", PF_PHONET, protocol) == 0)
		pnp = phonet_proto_get(protocol);
#endif
	if (pnp == NULL)
		return -EPROTONOSUPPORT;
	if (sock->type != pnp->sock_type) {
		err = -EPROTONOSUPPORT;
		goto out;
	}

	sk = sk_alloc(net, PF_PHONET, GFP_KERNEL, pnp->prot);
	if (sk == NULL) {
		err = -ENOMEM;
		goto out;
	}

	sock_init_data(sock, sk);
	sock->state = SS_UNCONNECTED;
	sock->ops = pnp->ops;
	sk->sk_backlog_rcv = sk->sk_prot->backlog_rcv;
	sk->sk_protocol = protocol;
	pn = pn_sk(sk);
	pn->sobject = 0;
	pn->resource = 0;
	sk->sk_prot->init(sk);
	err = 0;

out:
	phonet_proto_put(pnp);
	return err;
}

static struct net_proto_family phonet_proto_family = {
	.family = PF_PHONET,
	.create = pn_socket_create,
	.owner = THIS_MODULE,
};

/* Phonet device header operations */
static int pn_header_create(struct sk_buff *skb, struct net_device *dev,
				unsigned short type, const void *daddr,
				const void *saddr, unsigned len)
{
	u8 *media = skb_push(skb, 1);

	if (type != ETH_P_PHONET)
		return -1;

	if (!saddr)
		saddr = dev->dev_addr;
	*media = *(const u8 *)saddr;
	return 1;
}

static int pn_header_parse(const struct sk_buff *skb, unsigned char *haddr)
{
	const u8 *media = skb_mac_header(skb);
	*haddr = *media;
	return 1;
}

struct header_ops phonet_header_ops = {
	.create = pn_header_create,
	.parse = pn_header_parse,
};
EXPORT_SYMBOL(phonet_header_ops);

/*
 * Prepends an ISI header and sends a datagram.
 */
static int pn_send(struct sk_buff *skb, struct net_device *dev,
			u16 dst, u16 src, u8 res, u8 irq)
{
	struct phonethdr *ph;
	int err;

	if (skb->len + 2 > 0xffff) {
		/* Phonet length field would overflow */
		err = -EMSGSIZE;
		goto drop;
	}

	skb_reset_transport_header(skb);
	WARN_ON(skb_headroom(skb) & 1); /* HW assumes word alignment */
	skb_push(skb, sizeof(struct phonethdr));
	skb_reset_network_header(skb);
	ph = pn_hdr(skb);
	ph->pn_rdev = pn_dev(dst);
	ph->pn_sdev = pn_dev(src);
	ph->pn_res = res;
	ph->pn_length = __cpu_to_be16(skb->len + 2 - sizeof(*ph));
	ph->pn_robj = pn_obj(dst);
	ph->pn_sobj = pn_obj(src);

	skb->protocol = htons(ETH_P_PHONET);
	skb->priority = 0;
	skb->dev = dev;

	if (pn_addr(src) == pn_addr(dst)) {
		skb_reset_mac_header(skb);
		skb->pkt_type = PACKET_LOOPBACK;
		skb_orphan(skb);
		if (irq)
			netif_rx(skb);
		else
			netif_rx_ni(skb);
		err = 0;
	} else {
		err = dev_hard_header(skb, dev, ntohs(skb->protocol),
					NULL, NULL, skb->len);
		if (err < 0) {
			err = -EHOSTUNREACH;
			goto drop;
		}
		err = dev_queue_xmit(skb);
	}

	return err;
drop:
	kfree_skb(skb);
	return err;
}

static int pn_raw_send(const void *data, int len, struct net_device *dev,
			u16 dst, u16 src, u8 res)
{
	struct sk_buff *skb = alloc_skb(MAX_PHONET_HEADER + len, GFP_ATOMIC);
	if (skb == NULL)
		return -ENOMEM;

	skb_reserve(skb, MAX_PHONET_HEADER);
	__skb_put(skb, len);
	skb_copy_to_linear_data(skb, data, len);
	return pn_send(skb, dev, dst, src, res, 1);
}

/*
 * Create a Phonet header for the skb and send it out. Returns
 * non-zero error code if failed. The skb is freed then.
 */
int pn_skb_send(struct sock *sk, struct sk_buff *skb,
		const struct sockaddr_pn *target)
{
	struct net_device *dev;
	struct pn_sock *pn = pn_sk(sk);
	int err;
	u16 src;
	u8 daddr = pn_sockaddr_get_addr(target), saddr = PN_NO_ADDR;

	err = -EHOSTUNREACH;
	if (sk->sk_bound_dev_if)
		dev = dev_get_by_index(sock_net(sk), sk->sk_bound_dev_if);
	else
		dev = phonet_device_get(sock_net(sk));
	if (!dev || !(dev->flags & IFF_UP))
		goto drop;

	saddr = phonet_address_get(dev, daddr);
	if (saddr == PN_NO_ADDR)
		goto drop;

	src = pn->sobject;
	if (!pn_addr(src))
		src = pn_object(saddr, pn_obj(src));

	err = pn_send(skb, dev, pn_sockaddr_get_object(target),
			src, pn_sockaddr_get_resource(target), 0);
	dev_put(dev);
	return err;

drop:
	kfree_skb(skb);
	if (dev)
		dev_put(dev);
	return err;
}
EXPORT_SYMBOL(pn_skb_send);

/* Do not send an error message in response to an error message */
static inline int can_respond(struct sk_buff *skb)
{
	const struct phonethdr *ph;
	const struct phonetmsg *pm;
	u8 submsg_id;

	if (!pskb_may_pull(skb, 3))
		return 0;

	ph = pn_hdr(skb);
	if (phonet_address_get(skb->dev, ph->pn_rdev) != ph->pn_rdev)
		return 0; /* we are not the destination */
	if (ph->pn_res == PN_PREFIX && !pskb_may_pull(skb, 5))
		return 0;

	ph = pn_hdr(skb); /* re-acquires the pointer */
	pm = pn_msg(skb);
	if (pm->pn_msg_id != PN_COMMON_MESSAGE)
		return 1;
	submsg_id = (ph->pn_res == PN_PREFIX)
		? pm->pn_e_submsg_id : pm->pn_submsg_id;
	if (submsg_id != PN_COMM_ISA_ENTITY_NOT_REACHABLE_RESP &&
		pm->pn_e_submsg_id != PN_COMM_SERVICE_NOT_IDENTIFIED_RESP)
		return 1;
	return 0;
}

static int send_obj_unreachable(struct sk_buff *rskb)
{
	const struct phonethdr *oph = pn_hdr(rskb);
	const struct phonetmsg *opm = pn_msg(rskb);
	struct phonetmsg resp;

	memset(&resp, 0, sizeof(resp));
	resp.pn_trans_id = opm->pn_trans_id;
	resp.pn_msg_id = PN_COMMON_MESSAGE;
	if (oph->pn_res == PN_PREFIX) {
		resp.pn_e_res_id = opm->pn_e_res_id;
		resp.pn_e_submsg_id = PN_COMM_ISA_ENTITY_NOT_REACHABLE_RESP;
		resp.pn_e_orig_msg_id = opm->pn_msg_id;
		resp.pn_e_status = 0;
	} else {
		resp.pn_submsg_id = PN_COMM_ISA_ENTITY_NOT_REACHABLE_RESP;
		resp.pn_orig_msg_id = opm->pn_msg_id;
		resp.pn_status = 0;
	}
	return pn_raw_send(&resp, sizeof(resp), rskb->dev,
				pn_object(oph->pn_sdev, oph->pn_sobj),
				pn_object(oph->pn_rdev, oph->pn_robj),
				oph->pn_res);
}

static int send_reset_indications(struct sk_buff *rskb)
{
	struct phonethdr *oph = pn_hdr(rskb);
	static const u8 data[4] = {
		0x00 /* trans ID */, 0x10 /* subscribe msg */,
		0x00 /* subscription count */, 0x00 /* dummy */
	};

	return pn_raw_send(data, sizeof(data), rskb->dev,
				pn_object(oph->pn_sdev, 0x00),
				pn_object(oph->pn_rdev, oph->pn_robj), 0x10);
}


/* packet type functions */

/*
 * Stuff received packets to associated sockets.
 * On error, returns non-zero and releases the skb.
 */
static int phonet_rcv(struct sk_buff *skb, struct net_device *dev,
			struct packet_type *pkttype,
			struct net_device *orig_dev)
{
	struct phonethdr *ph;
	struct sock *sk;
	struct sockaddr_pn sa;
	u16 len;

	if (dev_net(dev) != &init_net)
		goto out;

	/* check we have at least a full Phonet header */
	if (!pskb_pull(skb, sizeof(struct phonethdr)))
		goto out;

	/* check that the advertised length is correct */
	ph = pn_hdr(skb);
	len = get_unaligned_be16(&ph->pn_length);
	if (len < 2)
		goto out;
	len -= 2;
	if ((len > skb->len) || pskb_trim(skb, len))
		goto out;
	skb_reset_transport_header(skb);

	pn_skb_get_dst_sockaddr(skb, &sa);
	if (pn_sockaddr_get_addr(&sa) == 0)
		goto out; /* currently, we cannot be device 0 */

	sk = pn_find_sock_by_sa(&sa);
	if (sk == NULL) {
		if (can_respond(skb)) {
			send_obj_unreachable(skb);
			send_reset_indications(skb);
		}
		goto out;
	}

	/* Push data to the socket (or other sockets connected to it). */
	return sk_receive_skb(sk, skb, 0);

out:
	kfree_skb(skb);
	return NET_RX_DROP;
}

static struct packet_type phonet_packet_type = {
	.type = __constant_htons(ETH_P_PHONET),
	.dev = NULL,
	.func = phonet_rcv,
};

/* Transport protocol registration */
static struct phonet_protocol *proto_tab[PHONET_NPROTO] __read_mostly;
static DEFINE_SPINLOCK(proto_tab_lock);

int __init_or_module phonet_proto_register(int protocol,
						struct phonet_protocol *pp)
{
	int err = 0;

	if (protocol >= PHONET_NPROTO)
		return -EINVAL;

	err = proto_register(pp->prot, 1);
	if (err)
		return err;

	spin_lock(&proto_tab_lock);
	if (proto_tab[protocol])
		err = -EBUSY;
	else
		proto_tab[protocol] = pp;
	spin_unlock(&proto_tab_lock);

	return err;
}
EXPORT_SYMBOL(phonet_proto_register);

void phonet_proto_unregister(int protocol, struct phonet_protocol *pp)
{
	spin_lock(&proto_tab_lock);
	BUG_ON(proto_tab[protocol] != pp);
	proto_tab[protocol] = NULL;
	spin_unlock(&proto_tab_lock);
	proto_unregister(pp->prot);
}
EXPORT_SYMBOL(phonet_proto_unregister);

static struct phonet_protocol *phonet_proto_get(int protocol)
{
	struct phonet_protocol *pp;

	if (protocol >= PHONET_NPROTO)
		return NULL;

	spin_lock(&proto_tab_lock);
	pp = proto_tab[protocol];
	if (pp && !try_module_get(pp->prot->owner))
		pp = NULL;
	spin_unlock(&proto_tab_lock);

	return pp;
}

static inline void phonet_proto_put(struct phonet_protocol *pp)
{
	module_put(pp->prot->owner);
}

/* Module registration */
static int __init phonet_init(void)
{
	int err;

	err = sock_register(&phonet_proto_family);
	if (err) {
		printk(KERN_ALERT
			"phonet protocol family initialization failed\n");
		return err;
	}

	phonet_device_init();
	dev_add_pack(&phonet_packet_type);
	phonet_netlink_register();
	phonet_sysctl_init();

	err = isi_register();
	if (err)
		goto err;
	return 0;

err:
	phonet_sysctl_exit();
	sock_unregister(PF_PHONET);
	dev_remove_pack(&phonet_packet_type);
	phonet_device_exit();
	return err;
}

static void __exit phonet_exit(void)
{
	isi_unregister();
	phonet_sysctl_exit();
	sock_unregister(PF_PHONET);
	dev_remove_pack(&phonet_packet_type);
	phonet_device_exit();
}

module_init(phonet_init);
module_exit(phonet_exit);
MODULE_DESCRIPTION("Phonet protocol stack for Linux");
MODULE_LICENSE("GPL");
MODULE_ALIAS_NETPROTO(PF_PHONET);
Commit	Line	Data
4b07b3f6 RDC	1	/*
	2	* File: af_phonet.c
	3	*
	4	* Phonet protocols family
	5	*
	6	* Copyright (C) 2008 Nokia Corporation.
	7	*
	8	* Contact: Remi Denis-Courmont <remi.denis-courmont@nokia.com>
	9	* Original author: Sakari Ailus <sakari.ailus@nokia.com>
	10	*
	11	* This program is free software; you can redistribute it and/or
	12	* modify it under the terms of the GNU General Public License
	13	* version 2 as published by the Free Software Foundation.
	14	*
	15	* This program is distributed in the hope that it will be useful, but
	16	* WITHOUT ANY WARRANTY; without even the implied warranty of
	17	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	18	* General Public License for more details.
	19	*
	20	* You should have received a copy of the GNU General Public License
	21	* along with this program; if not, write to the Free Software
	22	* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
	23	* 02110-1301 USA
	24	*/
	25
	26	#include <linux/kernel.h>
	27	#include <linux/module.h>
	28	#include <asm/unaligned.h>
	29	#include <net/sock.h>
	30
	31	#include <linux/if_phonet.h>
	32	#include <linux/phonet.h>
	33	#include <net/phonet/phonet.h>
f8ff6028	34	#include <net/phonet/pn_dev.h>
4b07b3f6 RDC	35
	36	static struct net_proto_family phonet_proto_family;
	37	static struct phonet_protocol *phonet_proto_get(int protocol);
	38	static inline void phonet_proto_put(struct phonet_protocol *pp);
	39
	40	/* protocol family functions */
	41
	42	static int pn_socket_create(struct net net, struct socket sock, int protocol)
	43	{
ba113a94 RDC	44	struct sock *sk;
ba113a94 RDC	45	struct pn_sock *pn;
4b07b3f6 RDC	46	struct phonet_protocol *pnp;
	47	int err;
	48
	49	if (net != &init_net)
	50	return -EAFNOSUPPORT;
	51
	52	if (!capable(CAP_SYS_ADMIN))
	53	return -EPERM;
	54
	55	if (protocol == 0) {
	56	/* Default protocol selection */
	57	switch (sock->type) {
	58	case SOCK_DGRAM:
	59	protocol = PN_PROTO_PHONET;
	60	break;
9641458d RDC	61	case SOCK_SEQPACKET:
	62	protocol = PN_PROTO_PIPE;
	63	break;
4b07b3f6 RDC	64	default:
	65	return -EPROTONOSUPPORT;
	66	}
	67	}
	68
	69	pnp = phonet_proto_get(protocol);
25532824 RDC	70	#ifdef CONFIG_KMOD
	71	if (pnp == NULL &&
	72	request_module("net-pf-%d-proto-%d", PF_PHONET, protocol) == 0)
	73	pnp = phonet_proto_get(protocol);
	74	#endif
4b07b3f6 RDC	75	if (pnp == NULL)
	76	return -EPROTONOSUPPORT;
	77	if (sock->type != pnp->sock_type) {
	78	err = -EPROTONOSUPPORT;
	79	goto out;
	80	}
	81
ba113a94 RDC	82	sk = sk_alloc(net, PF_PHONET, GFP_KERNEL, pnp->prot);
	83	if (sk == NULL) {
	84	err = -ENOMEM;
	85	goto out;
	86	}
	87
	88	sock_init_data(sock, sk);
	89	sock->state = SS_UNCONNECTED;
	90	sock->ops = pnp->ops;
	91	sk->sk_backlog_rcv = sk->sk_prot->backlog_rcv;
	92	sk->sk_protocol = protocol;
	93	pn = pn_sk(sk);
	94	pn->sobject = 0;
	95	pn->resource = 0;
	96	sk->sk_prot->init(sk);
	97	err = 0;
4b07b3f6 RDC	98
	99	out:
	100	phonet_proto_put(pnp);
	101	return err;
	102	}
	103
	104	static struct net_proto_family phonet_proto_family = {
25532824	105	.family = PF_PHONET,
4b07b3f6 RDC	106	.create = pn_socket_create,
	107	.owner = THIS_MODULE,
	108	};
	109
5f77076d RDC	110	/* Phonet device header operations */
	111	static int pn_header_create(struct sk_buff skb, struct net_device dev,
	112	unsigned short type, const void *daddr,
	113	const void *saddr, unsigned len)
	114	{
	115	u8 *media = skb_push(skb, 1);
	116
	117	if (type != ETH_P_PHONET)
	118	return -1;
	119
	120	if (!saddr)
	121	saddr = dev->dev_addr;
	122	media = (const u8 *)saddr;
	123	return 1;
	124	}
	125
	126	static int pn_header_parse(const struct sk_buff skb, unsigned char haddr)
	127	{
	128	const u8 *media = skb_mac_header(skb);
	129	haddr = media;
	130	return 1;
	131	}
	132
	133	struct header_ops phonet_header_ops = {
	134	.create = pn_header_create,
	135	.parse = pn_header_parse,
	136	};
	137	EXPORT_SYMBOL(phonet_header_ops);
	138
107d0d9b RDC	139	/*
	140	* Prepends an ISI header and sends a datagram.
	141	*/
	142	static int pn_send(struct sk_buff skb, struct net_device dev,
be0c52bf	143	u16 dst, u16 src, u8 res, u8 irq)
107d0d9b RDC	144	{
	145	struct phonethdr *ph;
	146	int err;
	147
	148	if (skb->len + 2 > 0xffff) {
	149	/* Phonet length field would overflow */
	150	err = -EMSGSIZE;
	151	goto drop;
	152	}
	153
	154	skb_reset_transport_header(skb);
	155	WARN_ON(skb_headroom(skb) & 1); /* HW assumes word alignment */
	156	skb_push(skb, sizeof(struct phonethdr));
	157	skb_reset_network_header(skb);
	158	ph = pn_hdr(skb);
	159	ph->pn_rdev = pn_dev(dst);
	160	ph->pn_sdev = pn_dev(src);
	161	ph->pn_res = res;
	162	ph->pn_length = __cpu_to_be16(skb->len + 2 - sizeof(*ph));
	163	ph->pn_robj = pn_obj(dst);
	164	ph->pn_sobj = pn_obj(src);
	165
	166	skb->protocol = htons(ETH_P_PHONET);
	167	skb->priority = 0;
	168	skb->dev = dev;
	169
	170	if (pn_addr(src) == pn_addr(dst)) {
	171	skb_reset_mac_header(skb);
	172	skb->pkt_type = PACKET_LOOPBACK;
	173	skb_orphan(skb);
be0c52bf RDC	174	if (irq)
	175	netif_rx(skb);
	176	else
	177	netif_rx_ni(skb);
107d0d9b RDC	178	err = 0;
	179	} else {
	180	err = dev_hard_header(skb, dev, ntohs(skb->protocol),
	181	NULL, NULL, skb->len);
	182	if (err < 0) {
	183	err = -EHOSTUNREACH;
	184	goto drop;
	185	}
	186	err = dev_queue_xmit(skb);
	187	}
	188
	189	return err;
	190	drop:
	191	kfree_skb(skb);
	192	return err;
	193	}
	194
be0c52bf RDC	195	static int pn_raw_send(const void data, int len, struct net_device dev,
	196	u16 dst, u16 src, u8 res)
	197	{
	198	struct sk_buff *skb = alloc_skb(MAX_PHONET_HEADER + len, GFP_ATOMIC);
	199	if (skb == NULL)
	200	return -ENOMEM;
	201
	202	skb_reserve(skb, MAX_PHONET_HEADER);
	203	__skb_put(skb, len);
	204	skb_copy_to_linear_data(skb, data, len);
	205	return pn_send(skb, dev, dst, src, res, 1);
	206	}
	207
107d0d9b RDC	208	/*
	209	* Create a Phonet header for the skb and send it out. Returns
	210	* non-zero error code if failed. The skb is freed then.
	211	*/
	212	int pn_skb_send(struct sock sk, struct sk_buff skb,
	213	const struct sockaddr_pn *target)
	214	{
	215	struct net_device *dev;
	216	struct pn_sock *pn = pn_sk(sk);
	217	int err;
	218	u16 src;
	219	u8 daddr = pn_sockaddr_get_addr(target), saddr = PN_NO_ADDR;
	220
	221	err = -EHOSTUNREACH;
	222	if (sk->sk_bound_dev_if)
	223	dev = dev_get_by_index(sock_net(sk), sk->sk_bound_dev_if);
	224	else
	225	dev = phonet_device_get(sock_net(sk));
	226	if (!dev \|\| !(dev->flags & IFF_UP))
	227	goto drop;
	228
	229	saddr = phonet_address_get(dev, daddr);
	230	if (saddr == PN_NO_ADDR)
	231	goto drop;
	232
	233	src = pn->sobject;
	234	if (!pn_addr(src))
	235	src = pn_object(saddr, pn_obj(src));
	236
	237	err = pn_send(skb, dev, pn_sockaddr_get_object(target),
be0c52bf	238	src, pn_sockaddr_get_resource(target), 0);
107d0d9b RDC	239	dev_put(dev);
	240	return err;
	241
	242	drop:
	243	kfree_skb(skb);
	244	if (dev)
	245	dev_put(dev);
	246	return err;
	247	}
	248	EXPORT_SYMBOL(pn_skb_send);
	249
be0c52bf RDC	250	/* Do not send an error message in response to an error message */
	251	static inline int can_respond(struct sk_buff *skb)
	252	{
	253	const struct phonethdr *ph;
	254	const struct phonetmsg *pm;
	255	u8 submsg_id;
	256
	257	if (!pskb_may_pull(skb, 3))
	258	return 0;
	259
	260	ph = pn_hdr(skb);
	261	if (phonet_address_get(skb->dev, ph->pn_rdev) != ph->pn_rdev)
	262	return 0; /* we are not the destination */
	263	if (ph->pn_res == PN_PREFIX && !pskb_may_pull(skb, 5))
	264	return 0;
	265
	266	ph = pn_hdr(skb); /* re-acquires the pointer */
	267	pm = pn_msg(skb);
	268	if (pm->pn_msg_id != PN_COMMON_MESSAGE)
	269	return 1;
	270	submsg_id = (ph->pn_res == PN_PREFIX)
	271	? pm->pn_e_submsg_id : pm->pn_submsg_id;
	272	if (submsg_id != PN_COMM_ISA_ENTITY_NOT_REACHABLE_RESP &&
	273	pm->pn_e_submsg_id != PN_COMM_SERVICE_NOT_IDENTIFIED_RESP)
	274	return 1;
	275	return 0;
	276	}
	277
	278	static int send_obj_unreachable(struct sk_buff *rskb)
	279	{
	280	const struct phonethdr *oph = pn_hdr(rskb);
	281	const struct phonetmsg *opm = pn_msg(rskb);
	282	struct phonetmsg resp;
	283
	284	memset(&resp, 0, sizeof(resp));
	285	resp.pn_trans_id = opm->pn_trans_id;
	286	resp.pn_msg_id = PN_COMMON_MESSAGE;
	287	if (oph->pn_res == PN_PREFIX) {
	288	resp.pn_e_res_id = opm->pn_e_res_id;
	289	resp.pn_e_submsg_id = PN_COMM_ISA_ENTITY_NOT_REACHABLE_RESP;
	290	resp.pn_e_orig_msg_id = opm->pn_msg_id;
	291	resp.pn_e_status = 0;
	292	} else {
	293	resp.pn_submsg_id = PN_COMM_ISA_ENTITY_NOT_REACHABLE_RESP;
	294	resp.pn_orig_msg_id = opm->pn_msg_id;
	295	resp.pn_status = 0;
	296	}
	297	return pn_raw_send(&resp, sizeof(resp), rskb->dev,
	298	pn_object(oph->pn_sdev, oph->pn_sobj),
	299	pn_object(oph->pn_rdev, oph->pn_robj),
	300	oph->pn_res);
	301	}
	302
	303	static int send_reset_indications(struct sk_buff *rskb)
	304	{
	305	struct phonethdr *oph = pn_hdr(rskb);
	306	static const u8 data[4] = {
	307	0x00 /* trans ID /, 0x10 / subscribe msg */,
	308	0x00 /* subscription count /, 0x00 / dummy */
	309	};
	310
	311	return pn_raw_send(data, sizeof(data), rskb->dev,
	312	pn_object(oph->pn_sdev, 0x00),
	313	pn_object(oph->pn_rdev, oph->pn_robj), 0x10);
314	}
315
316
4b07b3f6 RDC	317	/* packet type functions */
	318
	319	/*
	320	* Stuff received packets to associated sockets.
	321	* On error, returns non-zero and releases the skb.
	322	*/
	323	static int phonet_rcv(struct sk_buff skb, struct net_device dev,
	324	struct packet_type *pkttype,
	325	struct net_device *orig_dev)
	326	{
	327	struct phonethdr *ph;
ba113a94	328	struct sock *sk;
4b07b3f6 RDC	329	struct sockaddr_pn sa;
	330	u16 len;
	331
	332	if (dev_net(dev) != &init_net)
	333	goto out;
	334
	335	/* check we have at least a full Phonet header */
	336	if (!pskb_pull(skb, sizeof(struct phonethdr)))
	337	goto out;
	338
	339	/* check that the advertised length is correct */
	340	ph = pn_hdr(skb);
	341	len = get_unaligned_be16(&ph->pn_length);
	342	if (len < 2)
	343	goto out;
	344	len -= 2;
	345	if ((len > skb->len) \|\| pskb_trim(skb, len))
	346	goto out;
	347	skb_reset_transport_header(skb);
	348
	349	pn_skb_get_dst_sockaddr(skb, &sa);
	350	if (pn_sockaddr_get_addr(&sa) == 0)
	351	goto out; /* currently, we cannot be device 0 */
	352
ba113a94	353	sk = pn_find_sock_by_sa(&sa);
be0c52bf RDC	354	if (sk == NULL) {
	355	if (can_respond(skb)) {
	356	send_obj_unreachable(skb);
	357	send_reset_indications(skb);
	358	}
ba113a94	359	goto out;
be0c52bf	360	}
ba113a94 RDC	361
	362	/* Push data to the socket (or other sockets connected to it). */
	363	return sk_receive_skb(sk, skb, 0);
4b07b3f6 RDC	364
	365	out:
	366	kfree_skb(skb);
	367	return NET_RX_DROP;
	368	}
	369
	370	static struct packet_type phonet_packet_type = {
	371	.type = __constant_htons(ETH_P_PHONET),
	372	.dev = NULL,
	373	.func = phonet_rcv,
	374	};
	375
	376	/* Transport protocol registration */
	377	static struct phonet_protocol *proto_tab[PHONET_NPROTO] __read_mostly;
	378	static DEFINE_SPINLOCK(proto_tab_lock);
	379
	380	int __init_or_module phonet_proto_register(int protocol,
	381	struct phonet_protocol *pp)
	382	{
	383	int err = 0;
	384
	385	if (protocol >= PHONET_NPROTO)
	386	return -EINVAL;
	387
	388	err = proto_register(pp->prot, 1);
	389	if (err)
	390	return err;
	391
	392	spin_lock(&proto_tab_lock);
	393	if (proto_tab[protocol])
	394	err = -EBUSY;
	395	else
	396	proto_tab[protocol] = pp;
	397	spin_unlock(&proto_tab_lock);
	398
	399	return err;
	400	}
	401	EXPORT_SYMBOL(phonet_proto_register);
	402
	403	void phonet_proto_unregister(int protocol, struct phonet_protocol *pp)
	404	{
	405	spin_lock(&proto_tab_lock);
	406	BUG_ON(proto_tab[protocol] != pp);
	407	proto_tab[protocol] = NULL;
	408	spin_unlock(&proto_tab_lock);
	409	proto_unregister(pp->prot);
	410	}
	411	EXPORT_SYMBOL(phonet_proto_unregister);
	412
	413	static struct phonet_protocol *phonet_proto_get(int protocol)
	414	{
	415	struct phonet_protocol *pp;
	416
	417	if (protocol >= PHONET_NPROTO)
	418	return NULL;
	419
	420	spin_lock(&proto_tab_lock);
	421	pp = proto_tab[protocol];
	422	if (pp && !try_module_get(pp->prot->owner))
	423	pp = NULL;
	424	spin_unlock(&proto_tab_lock);
	425
	426	return pp;
	427	}
428
429	static inline void phonet_proto_put(struct phonet_protocol *pp)
430	{
431	module_put(pp->prot->owner);
432	}
433
434	/* Module registration */
435	static int __init phonet_init(void)
436	{
437	int err;
438
439	err = sock_register(&phonet_proto_family);
440	if (err) {
441	printk(KERN_ALERT
442	"phonet protocol family initialization failed\n");
443	return err;
444	}
445
f8ff6028	446	phonet_device_init();
4b07b3f6	447	dev_add_pack(&phonet_packet_type);
8fb39740	448	phonet_netlink_register();
87ab4e20	449	phonet_sysctl_init();
107d0d9b RDC	450
	451	err = isi_register();
	452	if (err)
	453	goto err;
4b07b3f6	454	return 0;
107d0d9b RDC	455
107d0d9b RDC	456	err:
87ab4e20	457	phonet_sysctl_exit();
25532824	458	sock_unregister(PF_PHONET);
107d0d9b RDC	459	dev_remove_pack(&phonet_packet_type);
	460	phonet_device_exit();
	461	return err;
4b07b3f6 RDC	462	}
	463
	464	static void __exit phonet_exit(void)
	465	{
107d0d9b	466	isi_unregister();
87ab4e20	467	phonet_sysctl_exit();
25532824	468	sock_unregister(PF_PHONET);
4b07b3f6	469	dev_remove_pack(&phonet_packet_type);
f8ff6028	470	phonet_device_exit();
4b07b3f6 RDC	471	}
	472
	473	module_init(phonet_init);
	474	module_exit(phonet_exit);
	475	MODULE_DESCRIPTION("Phonet protocol stack for Linux");
	476	MODULE_LICENSE("GPL");
25532824	477	MODULE_ALIAS_NETPROTO(PF_PHONET);