1 files changed, 19 insertions, 5 deletions
diff --git a/proto/ospf/iface.c b/proto/ospf/iface.c
index 67ae094d..280fa4c1 100644
--- a/proto/ospf/iface.c
+++ b/proto/ospf/iface.c
@@ -9,6 +9,7 @@
  */
 
 #include "ospf.h"
+#include "nest/password.h"
 
 
 const char *ospf_is_names[] = {
@@ -52,6 +53,18 @@ ifa_tx_length(struct ospf_iface *ifa)
 }
 
 static inline uint
+ifa_tx_hdrlen(struct ospf_iface *ifa)
+{
+  uint hlen = SIZE_OF_IP_HEADER;
+
+  /* Relevant just for OSPFv2 */
+  if (ifa->autype == OSPF_AUTH_CRYPT)
+    hlen += max_mac_length(ifa->passwords);
+
+  return hlen;
+}
+
+static inline uint
 ifa_bufsize(struct ospf_iface *ifa)
 {
   uint bsize = ifa->cf->rx_buffer ?: ifa->iface->mtu;
@@ -67,11 +80,7 @@ ifa_flood_queue_size(struct ospf_iface *ifa)
 int
 ospf_iface_assure_bufsize(struct ospf_iface *ifa, uint plen)
 {
-  plen += SIZE_OF_IP_HEADER;
-
-  /* This is relevant just for OSPFv2 */
-  if (ifa->autype == OSPF_AUTH_CRYPT)
-    plen += OSPF_AUTH_CRYPT_SIZE;
+  plen += ifa->tx_hdrlen;
 
   if (plen <= ifa->sk->tbsize)
     return 0;
@@ -574,6 +583,7 @@ ospf_iface_new(struct ospf_area *oa, struct ifa *addr, struct ospf_iface_patt *i
   ifa->stub = ospf_iface_stubby(ip, addr);
   ifa->ioprob = OSPF_I_OK;
   ifa->tx_length = ifa_tx_length(ifa);
+  ifa->tx_hdrlen = ifa_tx_hdrlen(ifa);
   ifa->check_link = ip->check_link;
   ifa->ecmp_weight = ip->ecmp_weight;
   ifa->check_ttl = (ip->ttl_security == 1);
@@ -684,6 +694,7 @@ ospf_iface_new_vlink(struct ospf_proto *p, struct ospf_iface_patt *ip)
   ifa->deadint = ip->deadint;
   ifa->inftransdelay = ip->inftransdelay;
   ifa->tx_length = ospf_is_v2(p) ? IP4_MIN_MTU : IP6_MIN_MTU;
+  ifa->tx_hdrlen = ifa_tx_hdrlen(ifa);
   ifa->autype = ip->autype;
   ifa->passwords = ip->passwords;
   ifa->instance_id = ip->instance_id;
@@ -824,6 +835,9 @@ ospf_iface_reconfigure(struct ospf_iface *ifa, struct ospf_iface_patt *new)
   /* Update passwords */
   ifa->passwords = new->passwords;
 
+  /* Update header length */
+  ifa->tx_hdrlen = ifa_tx_hdrlen(ifa);
+
   /* Remaining options are just for proper interfaces */
   if (ifa->type == OSPF_IT_VLINK)
     return 1;