// SPDX-License-Identifier: GPL-2.0 /* * 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: *              Steve Whitehouse <steve@chygwyn.com> *              Updated for Thomas Graf's generic rules * */#include <linux/net.h>#include <linux/init.h>#include <linux/netlink.h>#include <linux/rtnetlink.h>#include <linux/netdevice.h>#include <linux/spinlock.h>#include <linux/list.h>#include <linux/rcupdate.h>#include <linux/export.h>#include <net/neighbour.h>#include <net/dst.h>#include <net/flow.h>#include <net/fib_rules.h>#include <net/dn.h>#include <net/dn_fib.h>#include <net/dn_neigh.h>#include <net/dn_dev.h>#include <net/dn_route.h> static struct fib_rules_ops *dn_fib_rules_ops; struct dn_fib_rule{	struct fib_rule		common;	unsigned char		dst_len;	unsigned char		src_len;	__le16			src;	__le16			srcmask;	__le16			dst;	__le16			dstmask;	__le16			srcmap;	u8			flags;};  int dn_fib_lookup(struct flowidn *flp, struct dn_fib_res *res){	struct fib_lookup_arg arg = {		.result = res,	};	int err; 	err = fib_rules_lookup(dn_fib_rules_ops,			       flowidn_to_flowi(flp), 0, &arg);	res->r = arg.rule; 	return err;} static int dn_fib_rule_action(struct fib_rule *rule, struct flowi *flp,			      int flags, struct fib_lookup_arg *arg){	struct flowidn *fld = &flp->u.dn;	int err = -EAGAIN;	struct dn_fib_table *tbl; 	switch(rule->action) {	case FR_ACT_TO_TBL:		break; 	case FR_ACT_UNREACHABLE:		err = -ENETUNREACH;		goto errout; 	case FR_ACT_PROHIBIT:		err = -EACCES;		goto errout; 	case FR_ACT_BLACKHOLE:	default:		err = -EINVAL;		goto errout;	} 	tbl = dn_fib_get_table(rule->table, 0);	if (tbl == NULL)		goto errout; 	err = tbl->lookup(tbl, fld, (struct dn_fib_res *)arg->result);	if (err > 0)		err = -EAGAIN;errout:	return err;} static const struct nla_policy dn_fib_rule_policy[FRA_MAX+1] = {	FRA_GENERIC_POLICY,}; static int dn_fib_rule_match(struct fib_rule *rule, struct flowi *fl, int flags){	struct dn_fib_rule *r = (struct dn_fib_rule *)rule;	struct flowidn *fld = &fl->u.dn;	__le16 daddr = fld->daddr;	__le16 saddr = fld->saddr; 	if (((saddr ^ r->src) & r->srcmask) ||	    ((daddr ^ r->dst) & r->dstmask))		return 0; 	return 1;} static int dn_fib_rule_configure(struct fib_rule *rule, struct sk_buff *skb,				 struct fib_rule_hdr *frh,				 struct nlattr **tb,				 struct netlink_ext_ack *extack){	int err = -EINVAL;	struct dn_fib_rule *r = (struct dn_fib_rule *)rule; 	if (frh->tos) {		NL_SET_ERR_MSG(extack, "Invalid tos value");		goto  errout;	} 	if (rule->table == RT_TABLE_UNSPEC) {		if (rule->action == FR_ACT_TO_TBL) {			struct dn_fib_table *table; 			table = dn_fib_empty_table();			if (table == NULL) {				err = -ENOBUFS;				goto errout;			} 			rule->table = table->n;		}	} 	if (frh->src_len)		r->src = nla_get_le16(tb[FRA_SRC]); 	if (frh->dst_len)		r->dst = nla_get_le16(tb[FRA_DST]); 	r->src_len = frh->src_len;	r->srcmask = dnet_make_mask(r->src_len);	r->dst_len = frh->dst_len;	r->dstmask = dnet_make_mask(r->dst_len);	err = 0;errout:	return err;} static int dn_fib_rule_compare(struct fib_rule *rule, struct fib_rule_hdr *frh,			       struct nlattr **tb){	struct dn_fib_rule *r = (struct dn_fib_rule *)rule; 	if (frh->src_len && (r->src_len != frh->src_len))		return 0; 	if (frh->dst_len && (r->dst_len != frh->dst_len))		return 0; 	if (frh->src_len && (r->src != nla_get_le16(tb[FRA_SRC])))		return 0; 	if (frh->dst_len && (r->dst != nla_get_le16(tb[FRA_DST])))		return 0; 	return 1;} unsigned int dnet_addr_type(__le16 addr){	struct flowidn fld = { .daddr = addr };	struct dn_fib_res res;	unsigned int ret = RTN_UNICAST;	struct dn_fib_table *tb = dn_fib_get_table(RT_TABLE_LOCAL, 0); 	res.r = NULL; 	if (tb) {		if (!tb->lookup(tb, &fld, &res)) {			ret = res.type;			dn_fib_res_put(&res);		}	}	return ret;} static int dn_fib_rule_fill(struct fib_rule *rule, struct sk_buff *skb,			    struct fib_rule_hdr *frh){	struct dn_fib_rule *r = (struct dn_fib_rule *)rule; 	frh->dst_len = r->dst_len;	frh->src_len = r->src_len;	frh->tos = 0; 	if ((r->dst_len &&	     nla_put_le16(skb, FRA_DST, r->dst)) ||	    (r->src_len &&	     nla_put_le16(skb, FRA_SRC, r->src)))		goto nla_put_failure;	return 0; nla_put_failure:	return -ENOBUFS;} static void dn_fib_rule_flush_cache(struct fib_rules_ops *ops){	dn_rt_cache_flush(-1);} static const struct fib_rules_ops __net_initconst dn_fib_rules_ops_template = {	.family		= AF_DECnet,	.rule_size	= sizeof(struct dn_fib_rule),	.addr_size	= sizeof(u16),	.action		= dn_fib_rule_action,	.match		= dn_fib_rule_match,	.configure	= dn_fib_rule_configure,	.compare	= dn_fib_rule_compare,	.fill		= dn_fib_rule_fill,	.flush_cache	= dn_fib_rule_flush_cache,	.nlgroup	= RTNLGRP_DECnet_RULE,	.policy		= dn_fib_rule_policy,	.owner		= THIS_MODULE,	.fro_net	= &init_net,}; void __init dn_fib_rules_init(void){	dn_fib_rules_ops =		fib_rules_register(&dn_fib_rules_ops_template, &init_net);	BUG_ON(IS_ERR(dn_fib_rules_ops));	BUG_ON(fib_default_rule_add(dn_fib_rules_ops, 0x7fff,			            RT_TABLE_MAIN, 0));} void __exit dn_fib_rules_cleanup(void){	rtnl_lock();	fib_rules_unregister(dn_fib_rules_ops);	rtnl_unlock();	rcu_barrier();}