radius: add support for route priority (metric) in Framed-Route

Let an optional route priority (aka metric) be defined in RADIUS
Framed-Route attributes.
The priority is an integer placed at the end of the route string. This
is backward compatible with the previous format and also conforms with
the recommended format defined by RFC 2865 (although we don't allow
multiple metrics).

Framed-Route format is:
<network> [<gateway> [<priority>]]

For example, 'Framed-Route = "192.0.2.0/24 203.0.113.1 8"' will let
the following route be installed (assuming 203.0.113.1 is routed
through eth0):
$ ip route show
[...]
192.0.2.0/24 via 203.0.113.1 dev eth0 metric 8

It's possible to use the unspecified gateway (0.0.0.0) if one wants to
set a priority without specifying a gateway address.

Finally, route deletion now also takes the priority into account, in
order to avoid removing a different route accidentally.

Signed-off-by: Guillaume Nault <g.nault@alphalink.fr>

2 files changed, 14 insertions, 3 deletions

diff --git a/accel-pppd/radius/radius.c b/accel-pppd/radius/radius.c
index b8706015..5c650b28 100644
--- a/accel-pppd/radius/radius.c
+++ b/accel-pppd/radius/radius.c
@@ -62,6 +62,7 @@ static void parse_framed_route(struct radius_pd_t *rpd, const char *attr)
 {
 	char str[32];
 	char *ptr;
+	long int prio = 0;
 	in_addr_t dst;
 	in_addr_t gw;
 	int mask;
@@ -118,6 +119,14 @@ static void parse_framed_route(struct radius_pd_t *rpd, const char *attr)
 			gw = 0;
 		else
 			goto out_err;
+
+		/* Parse priority, if any */
+		if (*ptr) {
+			for (++ptr; *ptr && *ptr != ' '; ptr++);
+			if (*ptr == ' ')
+				if (u_readlong(&prio, ptr + 1, 0, UINT32_MAX) < 0)
+					goto out_err;
+		}
 	} else {
 		mask = 32;
 		gw = 0;
@@ -127,6 +136,7 @@ static void parse_framed_route(struct radius_pd_t *rpd, const char *attr)
 	fr->dst = dst;
 	fr->mask = mask;
 	fr->gw = gw;
+	fr->prio = prio;
 	fr->next = rpd->fr;
 	rpd->fr = fr;
 
@@ -444,11 +454,11 @@ static void ses_started(struct ap_session *ses)
 	}
 
 	for (fr = rpd->fr; fr; fr = fr->next) {
-		if (iproute_add(fr->gw ? 0 : rpd->ses->ifindex, 0, fr->dst, fr->gw, 3, fr->mask)) {
+		if (iproute_add(fr->gw ? 0 : rpd->ses->ifindex, 0, fr->dst, fr->gw, 3, fr->mask, fr->prio)) {
 			char dst[17], gw[17];
 			u_inet_ntoa(fr->dst, dst);
 			u_inet_ntoa(fr->gw, gw);
-			log_ppp_warn("radius: failed to add route %s/%i%s\n", dst, fr->mask, gw);
+			log_ppp_warn("radius: failed to add route %s/%i %s %u\n", dst, fr->mask, gw, fr->prio);
 		}
 	}
 
@@ -472,7 +482,7 @@ static void ses_finishing(struct ap_session *ses)
 
 	for (fr = rpd->fr; fr; fr = fr->next) {
 		if (fr->gw)
-			iproute_del(0, fr->dst, 3, fr->mask);
+			iproute_del(0, fr->dst, 3, fr->mask, fr->prio);
 	}
 
 	if (rpd->acct_started || rpd->acct_req)
diff --git a/accel-pppd/radius/radius_p.h b/accel-pppd/radius/radius_p.h
index cdbb57b8..1ce31c03 100644
--- a/accel-pppd/radius/radius_p.h
+++ b/accel-pppd/radius/radius_p.h
@@ -29,6 +29,7 @@ struct framed_route {
 	in_addr_t dst;
 	int mask;
 	in_addr_t gw;
+	uint32_t prio;
 	struct framed_route *next;
 };