introduce route labels, allowing for up to 32 bytes of info to be attached

to a route.
the label is sent over the routing socket wrapped into a new
struct sockaddr_rtlabel, allowing for handling it like any other sockaddr.
struct rtentry only contains a (16 bit) label-ID, with the actual labels
kept outside the routing table.
ID allocator code inspired by my own code for altq and pf tags.
mostly hacked at the c2k4 hackathon, markus ok

3 files changed, 130 insertions, 4 deletions

diff --git a/sys/net/route.c b/sys/net/route.c
index 00d94f9bfea..d96e42183a2 100644
--- a/sys/net/route.c
+++ b/sys/net/route.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: route.c,v 1.46 2004/07/28 13:13:41 markus Exp $	*/
+/*	$OpenBSD: route.c,v 1.47 2004/08/03 11:22:15 henning Exp $	*/
 /*	$NetBSD: route.c,v 1.14 1996/02/13 22:00:46 christos Exp $	*/
 
 /*
@@ -111,6 +111,7 @@
 #include <sys/protosw.h>
 #include <sys/ioctl.h>
 #include <sys/kernel.h>
+#include <sys/queue.h>
 #include <sys/pool.h>
 
 #include <net/if.h>
@@ -147,6 +148,20 @@ static int rtdeletemsg(struct rtentry *);
 static int rtflushclone1(struct radix_node *, void *);
 static void rtflushclone(struct radix_node_head *, struct rtentry *);
 
+#define	LABELID_MAX	50000
+
+struct rt_label {
+	TAILQ_ENTRY(rt_label)	rtl_entry;
+	char			rtl_name[RTLABEL_LEN];
+	u_int16_t		rtl_id;
+	int			rtl_ref;
+};
+
+TAILQ_HEAD(rt_labels, rt_label)	rt_labels = TAILQ_HEAD_INITIALIZER(rt_labels);
+
+static u_int16_t	 rtlabel_name2id(char *);
+static void		 rtlabel_unref(u_int16_t);
+
 #ifdef IPSEC
 
 static struct ifaddr *
@@ -332,6 +347,7 @@ rtfree(rt)
 		ifa = rt->rt_ifa;
 		if (ifa)
 			IFAFREE(ifa);
+		rtlabel_unref(rt->rt_labelid);
 		Free(rt_key(rt));
 		pool_put(&rtentry_pool, rt);
 	}
@@ -670,6 +686,7 @@ rtrequest1(req, info, ret_nrt)
 	struct radix_node_head *rnh;
 	struct ifaddr *ifa;
 	struct sockaddr *ndst;
+	struct sockaddr_rtlabel	*sa_rl;
 #define senderr(x) { error = x ; goto bad; }
 
 	if ((rnh = rt_tables[dst->sa_family]) == 0)
@@ -767,6 +784,13 @@ rtrequest1(req, info, ret_nrt)
 			senderr(EEXIST);
 		}
 #endif
+
+		if (info->rti_info[RTAX_LABEL] != NULL) {
+			sa_rl = (struct sockaddr_rtlabel *)
+			    info->rti_info[RTAX_LABEL];
+			rt->rt_labelid = rtlabel_name2id(sa_rl->sr_label);
+		}
+
 		ifa->ifa_refcnt++;
 		rt->rt_ifa = ifa;
 		rt->rt_ifp = ifa->ifa_ifp;
@@ -1172,3 +1196,78 @@ rt_timer_timer(arg)
 
 	timeout_add(to, hz);		/* every second */
 }
+
+static u_int16_t
+rtlabel_name2id(char *name)
+{
+	struct rt_label		*label, *p = NULL;
+	u_int16_t		 new_id = 1;
+
+	TAILQ_FOREACH(label, &rt_labels, rtl_entry)
+		if (strcmp(name, label->rtl_name) == 0) {
+			label->rtl_ref++;
+			return (label->rtl_id);
+		}
+
+	/*
+	 * to avoid fragmentation, we do a linear search from the beginning
+	 * and take the first free slot we find. if there is none or the list
+	 * is empty, append a new entry at the end.
+	 */
+
+	if (!TAILQ_EMPTY(&rt_labels))
+		for (p = TAILQ_FIRST(&rt_labels); p != NULL &&
+		    p->rtl_id == new_id; p = TAILQ_NEXT(p, rtl_entry))
+			new_id = p->rtl_id + 1;
+
+	if (new_id > LABELID_MAX)
+		return (0);
+
+	label = (struct rt_label *)malloc(sizeof(struct rt_label),
+	    M_TEMP, M_NOWAIT);
+	if (label == NULL)
+		return (0);
+	bzero(label, sizeof(struct rt_label));
+	strlcpy(label->rtl_name, name, sizeof(label->rtl_name));
+	label->rtl_id = new_id;
+	label->rtl_ref++;
+
+	if (p != NULL)	/* insert new entry before p */
+		TAILQ_INSERT_BEFORE(p, label, rtl_entry);
+	else		/* either list empty or no free slot in between */
+		TAILQ_INSERT_TAIL(&rt_labels, label, rtl_entry);
+
+	return (label->rtl_id);
+}
+
+const char *
+rtlabel_id2name(u_int16_t id)
+{
+	struct rt_label	*label;
+
+	TAILQ_FOREACH(label, &rt_labels, rtl_entry)
+		if (label->rtl_id == id)
+			return (label->rtl_name);
+
+	return (NULL);
+}
+
+static void
+rtlabel_unref(u_int16_t id)
+{
+	struct rt_label	*p, *next;
+
+	if (id == 0)
+		return;
+
+	for (p = TAILQ_FIRST(&rt_labels); p != NULL; p = next) {
+		next = TAILQ_NEXT(p, rtl_entry);
+		if (id == p->rtl_id) {
+			if (--p->rtl_ref == 0) {
+				TAILQ_REMOVE(&rt_labels, p, rtl_entry);
+				free(p, M_TEMP);
+			}
+			break;
+		}
+	}
+}
diff --git a/sys/net/route.h b/sys/net/route.h
index 31a25a0e73e..1b167704d53 100644
--- a/sys/net/route.h
+++ b/sys/net/route.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: route.h,v 1.23 2004/06/19 19:55:53 cedric Exp $	*/
+/*	$OpenBSD: route.h,v 1.24 2004/08/03 11:22:15 henning Exp $	*/
 /*	$NetBSD: route.h,v 1.9 1996/02/13 22:00:49 christos Exp $	*/
 
 /*
@@ -116,6 +116,7 @@ struct rtentry {
 	struct	rtentry *rt_gwroute;	/* implied entry for gatewayed routes */
 	struct	rtentry *rt_parent;	/* If cloned, parent of this route. */
 	LIST_HEAD(, rttimer) rt_timer;  /* queue of timeouts for misc funcs */
+	u_int16_t rt_labelid;		/* route label ID */
 };
 #define	rt_use	rt_rmx.rmx_pksent
 
@@ -227,6 +228,7 @@ struct rt_msghdr {
 #define RTA_BRD		0x80	/* for NEWADDR, broadcast or p-p dest addr */
 #define RTA_SRC		0x100	/* source sockaddr present */
 #define RTA_SRCMASK	0x200	/* source netmask present */
+#define	RTA_LABEL	0x400	/* route label present */
 
 /*
  * Index offsets for sockaddr array for alternate internal encoding.
@@ -241,7 +243,8 @@ struct rt_msghdr {
 #define RTAX_BRD	7	/* for NEWADDR, broadcast or p-p dest addr */
 #define RTAX_SRC	8	/* source sockaddr present */
 #define RTAX_SRCMASK	9	/* source netmask present */
-#define RTAX_MAX	10	/* size of array to allocate */
+#define RTAX_LABEL	10	/* route label present */
+#define RTAX_MAX	11	/* size of array to allocate */
 
 struct rt_addrinfo {
 	int	rti_addrs;
@@ -283,6 +286,16 @@ struct rttimer_queue {
 	LIST_ENTRY(rttimer_queue)	rtq_link;
 };
 
+#define	RTLABEL_LEN	32
+
+struct sockaddr_rtlabel {
+	u_int8_t	sr_len;			/* total length */
+	sa_family_t	sr_family;		/* address family */
+	char		sr_label[RTLABEL_LEN];
+};
+
+const char	*rtlabel_id2name(u_int16_t);
+
 #ifdef _KERNEL
 #define	RTFREE(rt) do { \
 	if ((rt)->rt_refcnt <= 1) \
diff --git a/sys/net/rtsock.c b/sys/net/rtsock.c
index 9280cb1c994..41962950d62 100644
--- a/sys/net/rtsock.c
+++ b/sys/net/rtsock.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: rtsock.c,v 1.41 2004/06/24 22:25:25 henning Exp $	*/
+/*	$OpenBSD: rtsock.c,v 1.42 2004/08/03 11:22:15 henning Exp $	*/
 /*	$NetBSD: rtsock.c,v 1.18 1996/03/29 00:32:10 cgd Exp $	*/
 
 /*
@@ -180,6 +180,8 @@ route_output(struct mbuf *m, ...)
 	struct ifaddr		*ifa = NULL;
 	struct socket		*so;
 	struct rawcb		*rp = NULL;
+	struct sockaddr_rtlabel	 sa_rt;
+	const char		*label;
 	va_list			 ap;
 
 	va_start(ap, m);
@@ -320,6 +322,18 @@ report:
 			gate = rt->rt_gateway;
 			netmask = rt_mask(rt);
 			genmask = rt->rt_genmask;
+
+			if (rt->rt_labelid) {
+				bzero(&sa_rt, sizeof(sa_rt));
+				sa_rt.sr_len = sizeof(sa_rt);
+				label = rtlabel_id2name(rt->rt_labelid);
+				if (label != NULL)
+					strlcpy(sa_rt.sr_label, label,
+					    sizeof(sa_rt.sr_label));
+				info.rti_info[RTAX_LABEL] =
+				    (struct sockaddr *)&sa_rt;
+			}
+
 			ifpaddr = 0;
 			ifaaddr = 0;
 			if (rtm->rtm_addrs & (RTA_IFP | RTA_IFA) &&