ospfd: support write socket per interface

Add support for a write socket per interface, enabled by
default at the ospf instance level. An ospf instance-level
config allows this to be disabled, reverting to the older
behavior where a single per-instance socket is used for
sending and receiving packets.

Signed-off-by: Mark Stapp <mjs@labn.net>

1 files changed, 94 insertions, 20 deletions

diff --git a/ospfd/ospf_network.c b/ospfd/ospf_network.c
index bd5cd7682a..aff8ed05c7 100644
--- a/ospfd/ospf_network.c
+++ b/ospfd/ospf_network.c
@@ -15,6 +15,7 @@
 #include "sockopt.h"
 #include "privs.h"
 #include "lib_errors.h"
+#include "lib/table.h"
 
 #include "ospfd/ospfd.h"
 #include "ospfd/ospf_network.h"
@@ -119,61 +120,60 @@ int ospf_if_drop_alldrouters(struct ospf *top, struct prefix *p,
 	return ret;
 }
 
-int ospf_if_ipmulticast(struct ospf *top, struct prefix *p, ifindex_t ifindex)
+int ospf_if_ipmulticast(int fd, struct prefix *p, ifindex_t ifindex)
 {
 	uint8_t val;
 	int ret, len;
 
 	/* Prevent receiving self-origined multicast packets. */
-	ret = setsockopt_ipv4_multicast_loop(top->fd, 0);
+	ret = setsockopt_ipv4_multicast_loop(fd, 0);
 	if (ret < 0)
 		flog_err(EC_LIB_SOCKET,
 			 "can't setsockopt IP_MULTICAST_LOOP(0) for fd %d: %s",
-			 top->fd, safe_strerror(errno));
+			 fd, safe_strerror(errno));
 
 	/* Explicitly set multicast ttl to 1 -- endo. */
 	val = 1;
 	len = sizeof(val);
-	ret = setsockopt(top->fd, IPPROTO_IP, IP_MULTICAST_TTL, (void *)&val,
-			 len);
+	ret = setsockopt(fd, IPPROTO_IP, IP_MULTICAST_TTL, (void *)&val, len);
 	if (ret < 0)
 		flog_err(EC_LIB_SOCKET,
 			 "can't setsockopt IP_MULTICAST_TTL(1) for fd %d: %s",
-			 top->fd, safe_strerror(errno));
+			 fd, safe_strerror(errno));
 #ifndef GNU_LINUX
 	/* For GNU LINUX ospf_write uses IP_PKTINFO, in_pktinfo to send
 	 * packet out of ifindex. Below would be used Non Linux system.
 	 */
-	ret = setsockopt_ipv4_multicast_if(top->fd, p->u.prefix4, ifindex);
+	ret = setsockopt_ipv4_multicast_if(fd, p->u.prefix4, ifindex);
 	if (ret < 0)
 		flog_err(EC_LIB_SOCKET,
 			 "can't setsockopt IP_MULTICAST_IF(fd %d, addr %pI4, ifindex %u): %s",
-			 top->fd, &p->u.prefix4, ifindex,
+			 fd, &p->u.prefix4, ifindex,
 			 safe_strerror(errno));
 #endif
 
 	return ret;
 }
 
-int ospf_sock_init(struct ospf *ospf)
+/*
+ * Helper to open and set up a socket; returns the new fd on success,
+ * -1 on error.
+ */
+static int sock_init_common(vrf_id_t vrf_id, const char *name, int *pfd)
 {
 	int ospf_sock;
 	int ret, hincl = 1;
 
-	/* silently ignore. already done */
-	if (ospf->fd > 0)
-		return -1;
-
-	if (ospf->vrf_id == VRF_UNKNOWN) {
+	if (vrf_id == VRF_UNKNOWN) {
 		/* silently return since VRF is not ready */
 		return -1;
 	}
+
 	frr_with_privs(&ospfd_privs) {
 		ospf_sock = vrf_socket(AF_INET, SOCK_RAW, IPPROTO_OSPFIGP,
-				       ospf->vrf_id, ospf->name);
+				       vrf_id, name);
 		if (ospf_sock < 0) {
-			flog_err(EC_LIB_SOCKET,
-				 "ospf_read_sock_init: socket: %s",
+			flog_err(EC_LIB_SOCKET, "%s: socket: %s", __func__,
 				 safe_strerror(errno));
 			return -1;
 		}
@@ -212,10 +212,8 @@ int ospf_sock_init(struct ospf *ospf)
 				 ospf_sock);
 	}
 
-	/* Update socket buffer sizes */
-	ospf_sock_bufsize_update(ospf, ospf_sock, OSPF_SOCK_BOTH);
+	*pfd = ospf_sock;
 
-	ospf->fd = ospf_sock;
 	return ret;
 }
 
@@ -237,3 +235,79 @@ void ospf_sock_bufsize_update(const struct ospf *ospf, int sock,
 		setsockopt_so_sendbuf(sock, bufsize);
 	}
 }
+
+int ospf_sock_init(struct ospf *ospf)
+{
+	int ret;
+
+	/* silently ignore. already done */
+	if (ospf->fd > 0)
+		return -1;
+
+	ret = sock_init_common(ospf->vrf_id, ospf->name, &(ospf->fd));
+
+	if (ret >= 0) /* Update socket buffer sizes */
+		ospf_sock_bufsize_update(ospf, ospf->fd, OSPF_SOCK_BOTH);
+
+	return ret;
+}
+
+/*
+ * Open per-interface write socket
+ */
+int ospf_ifp_sock_init(struct interface *ifp)
+{
+	struct ospf_if_info *oii;
+	struct ospf_interface *oi;
+	struct ospf *ospf;
+	struct route_node *rn;
+	int ret;
+
+	oii = IF_OSPF_IF_INFO(ifp);
+	if (oii == NULL)
+		return -1;
+
+	if (oii->oii_fd > 0)
+		return 0;
+
+	rn = route_top(IF_OIFS(ifp));
+	if (rn && rn->info) {
+		oi = rn->info;
+		ospf = oi->ospf;
+	} else
+		return -1;
+
+	ret = sock_init_common(ifp->vrf->vrf_id, ifp->name, &oii->oii_fd);
+
+	if (ret >= 0) /* Update socket buffer sizes */
+		ospf_sock_bufsize_update(ospf, oii->oii_fd, OSPF_SOCK_BOTH);
+
+	if (IS_DEBUG_OSPF_EVENT)
+		zlog_debug("%s: ifp %s, oii %p, fd %d", __func__, ifp->name,
+			   oii, oii->oii_fd);
+
+	return ret;
+}
+
+/*
+ * Close per-interface write socket
+ */
+int ospf_ifp_sock_close(struct interface *ifp)
+{
+	struct ospf_if_info *oii;
+
+	oii = IF_OSPF_IF_INFO(ifp);
+	if (oii == NULL)
+		return 0;
+
+	if (oii->oii_fd > 0) {
+		if (IS_DEBUG_OSPF_EVENT)
+			zlog_debug("%s: ifp %s, oii %p, fd %d", __func__,
+				   ifp->name, oii, oii->oii_fd);
+
+		close(oii->oii_fd);
+		oii->oii_fd = -1;
+	}
+
+	return 0;
+}