/* * DECnet       An implementation of the DECnet protocol suite for the LINUX *              operating system.  DECnet is implemented using the  BSD Socket *              interface as the means of communication with the user level. * *              DECnet Routing Forwarding Information Base (Rules) * * Author:      Steve Whitehouse <SteveW@ACM.org> *              Mostly copied from Alexey Kuznetsov's ipv4/fib_rules.c * * * Changes: * */#include <linux/config.h>#include <linux/string.h>#include <linux/net.h>#include <linux/socket.h>#include <linux/sockios.h>#include <linux/init.h>#include <linux/skbuff.h>#include <linux/netlink.h>#include <linux/rtnetlink.h>#include <linux/proc_fs.h>#include <linux/netdevice.h>#include <linux/timer.h>#include <linux/spinlock.h>#include <linux/in_route.h>#include <linux/list.h>#include <linux/rcupdate.h>#include <asm/atomic.h>#include <asm/uaccess.h>#include <net/neighbour.h>#include <net/dst.h>#include <net/flow.h>#include <net/dn.h>#include <net/dn_fib.h>#include <net/dn_neigh.h>#include <net/dn_dev.h> struct dn_fib_rule{	struct hlist_node	r_hlist;	atomic_t		r_clntref;	u32			r_preference;	unsigned char		r_table;	unsigned char		r_action;	unsigned char		r_dst_len;	unsigned char		r_src_len;	__le16			r_src;	__le16			r_srcmask;	__le16			r_dst;	__le16			r_dstmask;	__le16			r_srcmap;	u8			r_flags;#ifdef CONFIG_DECNET_ROUTE_FWMARK	u32			r_fwmark;#endif	int			r_ifindex;	char			r_ifname[IFNAMSIZ];	int			r_dead;	struct rcu_head		rcu;}; static struct dn_fib_rule default_rule = {	.r_clntref =		ATOMIC_INIT(2),	.r_preference =		0x7fff,	.r_table =		RT_TABLE_MAIN,	.r_action =		RTN_UNICAST}; static struct hlist_head dn_fib_rules; int dn_fib_rtm_delrule(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg){	struct rtattr **rta = arg;	struct rtmsg *rtm = NLMSG_DATA(nlh);	struct dn_fib_rule *r;	struct hlist_node *node;	int err = -ESRCH; 	hlist_for_each_entry(r, node, &dn_fib_rules, r_hlist) {		if ((!rta[RTA_SRC-1] || memcmp(RTA_DATA(rta[RTA_SRC-1]), &r->r_src, 2) == 0) &&			rtm->rtm_src_len == r->r_src_len &&			rtm->rtm_dst_len == r->r_dst_len &&			(!rta[RTA_DST-1] || memcmp(RTA_DATA(rta[RTA_DST-1]), &r->r_dst, 2) == 0) &&#ifdef CONFIG_DECNET_ROUTE_FWMARK			(!rta[RTA_PROTOINFO-1] || memcmp(RTA_DATA(rta[RTA_PROTOINFO-1]), &r->r_fwmark, 4) == 0) &&#endif			(!rtm->rtm_type || rtm->rtm_type == r->r_action) &&			(!rta[RTA_PRIORITY-1] || memcmp(RTA_DATA(rta[RTA_PRIORITY-1]), &r->r_preference, 4) == 0) &&			(!rta[RTA_IIF-1] || rtattr_strcmp(rta[RTA_IIF-1], r->r_ifname) == 0) &&			(!rtm->rtm_table || (r && rtm->rtm_table == r->r_table))) { 			err = -EPERM;			if (r == &default_rule)				break; 			hlist_del_rcu(&r->r_hlist);			r->r_dead = 1;			dn_fib_rule_put(r);			err = 0;			break;		}	} 	return err;} static inline void dn_fib_rule_put_rcu(struct rcu_head *head){	struct dn_fib_rule *r = container_of(head, struct dn_fib_rule, rcu);	kfree(r);} void dn_fib_rule_put(struct dn_fib_rule *r){	if (atomic_dec_and_test(&r->r_clntref)) {		if (r->r_dead)			call_rcu(&r->rcu, dn_fib_rule_put_rcu);		else			printk(KERN_DEBUG "Attempt to free alive dn_fib_rule\n");	}}  int dn_fib_rtm_newrule(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg){	struct rtattr **rta = arg;	struct rtmsg *rtm = NLMSG_DATA(nlh);	struct dn_fib_rule *r, *new_r, *last = NULL;	struct hlist_node *node = NULL;	unsigned char table_id; 	if (rtm->rtm_src_len > 16 || rtm->rtm_dst_len > 16)		return -EINVAL; 	if (rta[RTA_IIF-1] && RTA_PAYLOAD(rta[RTA_IIF-1]) > IFNAMSIZ)		return -EINVAL; 	if (rtm->rtm_type == RTN_NAT)		return -EINVAL; 	table_id = rtm->rtm_table;	if (table_id == RT_TABLE_UNSPEC) {		struct dn_fib_table *tb;		if (rtm->rtm_type == RTN_UNICAST) {			if ((tb = dn_fib_empty_table()) == NULL)				return -ENOBUFS;			table_id = tb->n;		}	} 	new_r = kmalloc(sizeof(*new_r), GFP_KERNEL);	if (!new_r)		return -ENOMEM;	memset(new_r, 0, sizeof(*new_r)); 	if (rta[RTA_SRC-1])		memcpy(&new_r->r_src, RTA_DATA(rta[RTA_SRC-1]), 2);	if (rta[RTA_DST-1])		memcpy(&new_r->r_dst, RTA_DATA(rta[RTA_DST-1]), 2);	if (rta[RTA_GATEWAY-1])		memcpy(&new_r->r_srcmap, RTA_DATA(rta[RTA_GATEWAY-1]), 2);	new_r->r_src_len = rtm->rtm_src_len;	new_r->r_dst_len = rtm->rtm_dst_len;	new_r->r_srcmask = dnet_make_mask(rtm->rtm_src_len);	new_r->r_dstmask = dnet_make_mask(rtm->rtm_dst_len);#ifdef CONFIG_DECNET_ROUTE_FWMARK	if (rta[RTA_PROTOINFO-1])		memcpy(&new_r->r_fwmark, RTA_DATA(rta[RTA_PROTOINFO-1]), 4);#endif	new_r->r_action = rtm->rtm_type;	new_r->r_flags = rtm->rtm_flags;	if (rta[RTA_PRIORITY-1])		memcpy(&new_r->r_preference, RTA_DATA(rta[RTA_PRIORITY-1]), 4);	new_r->r_table = table_id;	if (rta[RTA_IIF-1]) {		struct net_device *dev;		rtattr_strlcpy(new_r->r_ifname, rta[RTA_IIF-1], IFNAMSIZ);		new_r->r_ifindex = -1;		dev = dev_get_by_name(new_r->r_ifname);		if (dev) {			new_r->r_ifindex = dev->ifindex;			dev_put(dev);		}	} 	r = container_of(dn_fib_rules.first, struct dn_fib_rule, r_hlist);	if (!new_r->r_preference) {		if (r && r->r_hlist.next != NULL) {			r = container_of(r->r_hlist.next, struct dn_fib_rule, r_hlist);			if (r->r_preference)				new_r->r_preference = r->r_preference - 1;		}	} 	hlist_for_each_entry(r, node, &dn_fib_rules, r_hlist) {		if (r->r_preference > new_r->r_preference)			break;		last = r;	}	atomic_inc(&new_r->r_clntref); 	if (last)		hlist_add_after_rcu(&last->r_hlist, &new_r->r_hlist);	else		hlist_add_before_rcu(&new_r->r_hlist, &r->r_hlist);	return 0;}  int dn_fib_lookup(const struct flowi *flp, struct dn_fib_res *res){	struct dn_fib_rule *r, *policy;	struct dn_fib_table *tb;	__le16 saddr = flp->fld_src;	__le16 daddr = flp->fld_dst;	struct hlist_node *node;	int err; 	rcu_read_lock(); 	hlist_for_each_entry_rcu(r, node, &dn_fib_rules, r_hlist) {		if (((saddr^r->r_src) & r->r_srcmask) ||		    ((daddr^r->r_dst) & r->r_dstmask) ||#ifdef CONFIG_DECNET_ROUTE_FWMARK		    (r->r_fwmark && r->r_fwmark != flp->fld_fwmark) ||#endif		    (r->r_ifindex && r->r_ifindex != flp->iif))			continue; 		switch(r->r_action) {			case RTN_UNICAST:			case RTN_NAT:				policy = r;				break;			case RTN_UNREACHABLE:				rcu_read_unlock();				return -ENETUNREACH;			default:			case RTN_BLACKHOLE:				rcu_read_unlock();				return -EINVAL;			case RTN_PROHIBIT:				rcu_read_unlock();				return -EACCES;		} 		if ((tb = dn_fib_get_table(r->r_table, 0)) == NULL)			continue;		err = tb->lookup(tb, flp, res);		if (err == 0) {			res->r = policy;			if (policy)				atomic_inc(&policy->r_clntref);			rcu_read_unlock();			return 0;		}		if (err < 0 && err != -EAGAIN) {			rcu_read_unlock();			return err;		}	} 	rcu_read_unlock();	return -ESRCH;} unsigned dnet_addr_type(__le16 addr){	struct flowi fl = { .nl_u = { .dn_u = { .daddr = addr } } };	struct dn_fib_res res;	unsigned ret = RTN_UNICAST;	struct dn_fib_table *tb = dn_fib_tables[RT_TABLE_LOCAL]; 	res.r = NULL; 	if (tb) {		if (!tb->lookup(tb, &fl, &res)) {			ret = res.type;			dn_fib_res_put(&res);		}	}	return ret;} __le16 dn_fib_rules_policy(__le16 saddr, struct dn_fib_res *res, unsigned *flags){	struct dn_fib_rule *r = res->r; 	if (r->r_action == RTN_NAT) {		int addrtype = dnet_addr_type(r->r_srcmap); 		if (addrtype == RTN_NAT) {			saddr = (saddr&~r->r_srcmask)|r->r_srcmap;			*flags |= RTCF_SNAT;		} else if (addrtype == RTN_LOCAL || r->r_srcmap == 0) {			saddr = r->r_srcmap;			*flags |= RTCF_MASQ;		}	}	return saddr;} static void dn_fib_rules_detach(struct net_device *dev){	struct hlist_node *node;	struct dn_fib_rule *r; 	hlist_for_each_entry(r, node, &dn_fib_rules, r_hlist) {		if (r->r_ifindex == dev->ifindex)			r->r_ifindex = -1;	}} static void dn_fib_rules_attach(struct net_device *dev){	struct hlist_node *node;	struct dn_fib_rule *r; 	hlist_for_each_entry(r, node, &dn_fib_rules, r_hlist) {		if (r->r_ifindex == -1 && strcmp(dev->name, r->r_ifname) == 0)			r->r_ifindex = dev->ifindex;	}} static int dn_fib_rules_event(struct notifier_block *this, unsigned long event, void *ptr){	struct net_device *dev = ptr; 	switch(event) {		case NETDEV_UNREGISTER:			dn_fib_rules_detach(dev);			dn_fib_sync_down(0, dev, 1);		case NETDEV_REGISTER:			dn_fib_rules_attach(dev);			dn_fib_sync_up(dev);	} 	return NOTIFY_DONE;}  static struct notifier_block dn_fib_rules_notifier = {	.notifier_call =	dn_fib_rules_event,}; static int dn_fib_fill_rule(struct sk_buff *skb, struct dn_fib_rule *r,			    struct netlink_callback *cb, unsigned int flags){	struct rtmsg *rtm;	struct nlmsghdr *nlh;	unsigned char *b = skb->tail;  	nlh = NLMSG_NEW_ANSWER(skb, cb, RTM_NEWRULE, sizeof(*rtm), flags);	rtm = NLMSG_DATA(nlh);	rtm->rtm_family = AF_DECnet;	rtm->rtm_dst_len = r->r_dst_len;	rtm->rtm_src_len = r->r_src_len;	rtm->rtm_tos = 0;#ifdef CONFIG_DECNET_ROUTE_FWMARK	if (r->r_fwmark)		RTA_PUT(skb, RTA_PROTOINFO, 4, &r->r_fwmark);#endif	rtm->rtm_table = r->r_table;	rtm->rtm_protocol = 0;	rtm->rtm_scope = 0;	rtm->rtm_type = r->r_action;	rtm->rtm_flags = r->r_flags; 	if (r->r_dst_len)		RTA_PUT(skb, RTA_DST, 2, &r->r_dst);	if (r->r_src_len)		RTA_PUT(skb, RTA_SRC, 2, &r->r_src);	if (r->r_ifname[0])		RTA_PUT(skb, RTA_IIF, IFNAMSIZ, &r->r_ifname);	if (r->r_preference)		RTA_PUT(skb, RTA_PRIORITY, 4, &r->r_preference);	if (r->r_srcmap)		RTA_PUT(skb, RTA_GATEWAY, 2, &r->r_srcmap);	nlh->nlmsg_len = skb->tail - b;	return skb->len; nlmsg_failure:rtattr_failure:	skb_trim(skb, b - skb->data);	return -1;} int dn_fib_dump_rules(struct sk_buff *skb, struct netlink_callback *cb){	int idx = 0;	int s_idx = cb->args[0];	struct dn_fib_rule *r;	struct hlist_node *node; 	rcu_read_lock();	hlist_for_each_entry(r, node, &dn_fib_rules, r_hlist) {		if (idx < s_idx)			continue;		if (dn_fib_fill_rule(skb, r, cb, NLM_F_MULTI) < 0)			break;		idx++;	}	rcu_read_unlock();	cb->args[0] = idx; 	return skb->len;} void __init dn_fib_rules_init(void){	INIT_HLIST_HEAD(&dn_fib_rules);	hlist_add_head(&default_rule.r_hlist, &dn_fib_rules);	register_netdevice_notifier(&dn_fib_rules_notifier);} void __exit dn_fib_rules_cleanup(void){	unregister_netdevice_notifier(&dn_fib_rules_notifier);}