1 files changed, 416 insertions, 0 deletions

diff --git a/net/decnet/dn_rules.c b/net/decnet/dn_rules.c
new file mode 100644
index 0000000..597587d
--- /dev/null
+++ b/net/decnet/dn_rules.c
@@ -0,0 +1,416 @@
+
+/*
+ * 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 <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 dn_fib_rule	*r_next;
+	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;
+	dn_address		r_src;
+	dn_address		r_srcmask;
+	dn_address		r_dst;
+	dn_address		r_dstmask;
+	dn_address		r_srcmap;
+	u8			r_flags;
+#ifdef CONFIG_DECNET_ROUTE_FWMARK
+	u32			r_fwmark;
+#endif
+	int			r_ifindex;
+	char			r_ifname[IFNAMSIZ];
+	int			r_dead;
+};
+
+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 dn_fib_rule *dn_fib_rules = &default_rule;
+static DEFINE_RWLOCK(dn_fib_rules_lock);
+
+
+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, **rp;
+	int err = -ESRCH;
+
+	for(rp=&dn_fib_rules; (r=*rp) != NULL; rp = &r->r_next) {
+		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;
+
+			write_lock_bh(&dn_fib_rules_lock);
+			*rp = r->r_next;
+			r->r_dead = 1;
+			write_unlock_bh(&dn_fib_rules_lock);
+			dn_fib_rule_put(r);
+			err = 0;
+			break;
+		}
+	}
+
+	return err;
+}
+
+void dn_fib_rule_put(struct dn_fib_rule *r)
+{
+	if (atomic_dec_and_test(&r->r_clntref)) {
+		if (r->r_dead)
+			kfree(r);
+		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, **rp;
+	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);
+		}
+	}
+
+	rp = &dn_fib_rules;
+	if (!new_r->r_preference) {
+		r = dn_fib_rules;
+		if (r && (r = r->r_next) != NULL) {
+			rp = &dn_fib_rules->r_next;
+			if (r->r_preference)
+				new_r->r_preference = r->r_preference - 1;
+		}
+	}
+
+	while((r=*rp) != NULL) {
+		if (r->r_preference > new_r->r_preference)
+			break;
+		rp = &r->r_next;
+	}
+
+	new_r->r_next = r;
+	atomic_inc(&new_r->r_clntref);
+	write_lock_bh(&dn_fib_rules_lock);
+	*rp = new_r;
+	write_unlock_bh(&dn_fib_rules_lock);
+	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;
+	dn_address saddr = flp->fld_src;
+	dn_address daddr = flp->fld_dst;
+	int err;
+
+	read_lock(&dn_fib_rules_lock);
+	for(r = dn_fib_rules; r; r = r->r_next) {
+		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:
+				read_unlock(&dn_fib_rules_lock);
+				return -ENETUNREACH;
+			default:
+			case RTN_BLACKHOLE:
+				read_unlock(&dn_fib_rules_lock);
+				return -EINVAL;
+			case RTN_PROHIBIT:
+				read_unlock(&dn_fib_rules_lock);
+				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);
+			read_unlock(&dn_fib_rules_lock);
+			return 0;
+		}
+		if (err < 0 && err != -EAGAIN) {
+			read_unlock(&dn_fib_rules_lock);
+			return err;
+		}
+	}
+
+	read_unlock(&dn_fib_rules_lock);
+	return -ESRCH;
+}
+
+unsigned dnet_addr_type(__u16 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;
+}
+
+__u16 dn_fib_rules_policy(__u16 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 dn_fib_rule *r;
+
+	for(r = dn_fib_rules; r; r = r->r_next) {
+		if (r->r_ifindex == dev->ifindex) {
+			write_lock_bh(&dn_fib_rules_lock);
+			r->r_ifindex = -1;
+			write_unlock_bh(&dn_fib_rules_lock);
+		}
+	}
+}
+
+static void dn_fib_rules_attach(struct net_device *dev)
+{
+	struct dn_fib_rule *r;
+
+	for(r = dn_fib_rules; r; r = r->r_next) {
+		if (r->r_ifindex == -1 && strcmp(dev->name, r->r_ifname) == 0) {
+			write_lock_bh(&dn_fib_rules_lock);
+			r->r_ifindex = dev->ifindex;
+			write_unlock_bh(&dn_fib_rules_lock);
+		}
+	}
+}
+
+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)
+{
+	struct rtmsg *rtm;
+	struct nlmsghdr *nlh;
+	unsigned char *b = skb->tail;
+
+
+	nlh = NLMSG_PUT(skb, NETLINK_CREDS(cb->skb)->pid, cb->nlh->nlmsg_seq, RTM_NEWRULE, sizeof(*rtm));
+	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;
+	int s_idx = cb->args[0];
+	struct dn_fib_rule *r;
+
+	read_lock(&dn_fib_rules_lock);
+	for(r = dn_fib_rules, idx = 0; r; r = r->r_next, idx++) {
+		if (idx < s_idx)
+			continue;
+		if (dn_fib_fill_rule(skb, r, cb) < 0)
+			break;
+	}
+	read_unlock(&dn_fib_rules_lock);
+	cb->args[0] = idx;
+
+	return skb->len;
+}
+
+void __init dn_fib_rules_init(void)
+{
+	register_netdevice_notifier(&dn_fib_rules_notifier);
+}
+
+void __exit dn_fib_rules_cleanup(void)
+{
+	unregister_netdevice_notifier(&dn_fib_rules_notifier);
+}
+
+