Fixes a compatibility issue in OSPFv2 PtP links.

BIRD used zero netmask in hello packets on all PtP links, not just on
unnumbered ones. This patch fixes it and adds option 'ptp netmask'
for overriding the default behavior.

Thanks to Alexander V. Chernikov for the original patch.

diff --git a/doc/bird.sgml b/doc/bird.sgml
index 300a71f3f9264737c051bc9739adb16baa195548..fab49105cc4fa4cd1a95d6ecd8baaa68219ed56c 100644 (file)
--- a/doc/bird.sgml
+++ b/doc/bird.sgml
@@ -1940,6 +1940,7 @@ protocol ospf <name> {
                                nonbroadcast|nbma|pointomultipoint|ptmp];
                        strict nonbroadcast <switch>;
                        real broadcast <switch>;
+                       ptp netmask <switch>;
                        check link <switch>;
                        ecmp weight <num>;
                        authentication [none|simple|cryptographic];
@@ -2183,6 +2184,18 @@ protocol ospf <name> {
         probably is not interoperable with other OSPF
         implementations. Default value is no.
 
+       <tag>ptp netmask <m/switch/</tag>
+        In <cf/type ptp/ network configurations, OSPFv2
+        implementations should ignore received netmask field in hello
+        packets and should send hello packets with zero netmask field
+        on unnumbered PtP links. But some OSPFv2 implementations
+        perform netmask checking even for PtP links. This option
+        specifies whether real netmask will be used in hello packets
+        on <cf/type ptp/ interfaces. You should ignore this option
+        unless you meet some compatibility problems related to this
+        issue. Default value is no for unnumbered PtP links, yes
+        otherwise.
+
        <tag>check link <M>switch</M></tag>
         If set, a hardware link state (reported by OS) is taken into
         consideration. When a link disappears (e.g. an ethernet cable is

diff --git a/proto/ospf/config.Y b/proto/ospf/config.Y
index b16d46a905bc2a1d5dd3c2591e506bd78bc6c522..2cc0b9634d65509881b51c5650af4dbd8c47a73e 100644 (file)
--- a/proto/ospf/config.Y
+++ b/proto/ospf/config.Y
@@ -131,7 +131,7 @@ CF_KEYWORDS(NONE, SIMPLE, AUTHENTICATION, STRICT, CRYPTOGRAPHIC)
 CF_KEYWORDS(ELIGIBLE, POLL, NETWORKS, HIDDEN, VIRTUAL, CHECK, LINK)
 CF_KEYWORDS(RX, BUFFER, LARGE, NORMAL, STUBNET, HIDDEN, SUMMARY, TAG, EXTERNAL)
 CF_KEYWORDS(WAIT, DELAY, LSADB, ECMP, LIMIT, WEIGHT, NSSA, TRANSLATOR, STABILITY)
-CF_KEYWORDS(GLOBAL, LSID, ROUTER, SELF, INSTANCE, REAL)
+CF_KEYWORDS(GLOBAL, LSID, ROUTER, SELF, INSTANCE, REAL, NETMASK)
 
 %type <t> opttext
 %type <ld> lsadb_args
@@ -290,6 +290,7 @@ ospf_iface_item:
  | TYPE POINTOMULTIPOINT { OSPF_PATT->type = OSPF_IT_PTMP ; }
  | TYPE PTMP { OSPF_PATT->type = OSPF_IT_PTMP ; }
  | REAL BROADCAST bool { OSPF_PATT->real_bcast = $3; if (OSPF_VERSION != 2) cf_error("Real broadcast option requires OSPFv2"); }
+ | PTP NETMASK bool { OSPF_PATT->ptp_netmask = $3; if (OSPF_VERSION != 2) cf_error("Real netmask option requires OSPFv2"); }
  | TRANSMIT DELAY expr { OSPF_PATT->inftransdelay = $3 ; if (($3<=0) || ($3>65535)) cf_error("Transmit delay must be in range 1-65535"); }
  | PRIORITY expr { OSPF_PATT->priority = $2 ; if (($2<0) || ($2>255)) cf_error("Priority must be in range 0-255"); }
  | STRICT NONBROADCAST bool { OSPF_PATT->strictnbma = $3 ; }
@@ -364,6 +365,7 @@ ospf_iface_start:
   OSPF_PATT->type = OSPF_IT_UNDEF;
   init_list(&OSPF_PATT->nbma_list);
   OSPF_PATT->autype = OSPF_AUTH_NONE;
+  OSPF_PATT->ptp_netmask = 2; /* not specified */
   reset_passwords();
  }
 ;

diff --git a/proto/ospf/hello.c b/proto/ospf/hello.c
index 6ec5c511bec88576247b00242584ef936af4d2b1..d5aa1b95eddcf04ef29c910492b548381e8c3c22 100644 (file)
--- a/proto/ospf/hello.c
+++ b/proto/ospf/hello.c
@@ -253,7 +253,8 @@ ospf_hello_send(struct ospf_iface *ifa, int kind, struct ospf_neighbor *dirn)
 #ifdef OSPFv2
   pkt->netmask = ipa_mkmask(ifa->addr->pxlen);
   ipa_hton(pkt->netmask);
-  if ((ifa->type == OSPF_IT_VLINK) || (ifa->type == OSPF_IT_PTP))
+  if ((ifa->type == OSPF_IT_VLINK) ||
+      ((ifa->type == OSPF_IT_PTP) && !ifa->ptp_netmask))
     pkt->netmask = IPA_NONE;
 #endif
 

diff --git a/proto/ospf/iface.c b/proto/ospf/iface.c
index 39084cef04199a2c7797028e8d0958b7847f0834..9050f7b10f77ed9f21a151a1f219119671aef406 100644 (file)
--- a/proto/ospf/iface.c
+++ b/proto/ospf/iface.c
@@ -537,6 +537,9 @@ ospf_iface_new(struct ospf_area *oa, struct ifa *addr, struct ospf_iface_patt *i
 #ifdef OSPFv2
   ifa->autype = ip->autype;
   ifa->passwords = ip->passwords;
+  ifa->ptp_netmask = !(addr->flags & IA_PEER);
+  if (ip->ptp_netmask < 2)
+    ifa->ptp_netmask = ip->ptp_netmask;
 #endif
 
 #ifdef OSPFv3

diff --git a/proto/ospf/ospf.h b/proto/ospf/ospf.h
index 7111a13dfdeecfdd0673d455d78572a68a8d8f3a..d924e6574a37d42cf571775ef18d26af763ce01f 100644 (file)
--- a/proto/ospf/ospf.h
+++ b/proto/ospf/ospf.h
@@ -273,6 +273,7 @@ struct ospf_iface
   u16 rxbuf;                   /* Buffer size */
   u8 check_link;               /* Whether iface link change is used */
   u8 ecmp_weight;              /* Weight used for ECMP */
+  u8 ptp_netmask;              /* Send real netmask for P2P */
 };
 
 struct ospf_md5
@@ -810,6 +811,7 @@ struct ospf_iface_patt
   u8 check_link;
   u8 ecmp_weight;
   u8 real_bcast;               /* Not really used in OSPFv3 */
+  u8 ptp_netmask;              /* bool but 2 for unspecified */
 
 #ifdef OSPFv2
   list *passwords;