Hi Joel, your fix sounds reasonable. In fact, I'm not even sure if the sin6_scope_id should be set for multicast. Maybe it should be done only for link local addresses.
Additionally, I guess the selection of the default interface (for IPv6) should be improved because I still can imagine a scenario where the first interface only has IPv4 but you want to do an IPv6 link local connect where you need a scope. Do you have signed an OCA as per [1], section "0. Become a Contributor"? Then I can help you with sponsoring this... Best regards Christoph [1] http://openjdk.java.net/contribute/ > -----Original Message----- > From: net-dev [mailto:net-dev-boun...@openjdk.java.net] On Behalf Of > Joel Peláez Jorge > Sent: Dienstag, 10. April 2018 00:37 > To: net-dev@openjdk.java.net > Subject: JDK-8200719: Cannot connect to IPv6 host when exists any active > network interface without IPv6 address > > Hi, > > I am new in the OpenJDK Community and I contribute with a fix for the bug > 8200719 related to networking in macOS system. > > I wrote a minimal patch that only set the scope id when the address is link- > local or multicast. This change avoid send IPv6 packets on a wrong interface. > > Bug: https://bugs.openjdk.java.net/browse/JDK-8200719 > > Patch: > > diff -r f088ec60bed5 src/java.base/unix/native/libnet/net_util_md.c > --- a/src/java.base/unix/native/libnet/net_util_md.c Mon Apr 09 10:39:29 > 2018 -0700 > +++ b/src/java.base/unix/native/libnet/net_util_md.c Mon Apr 09 16:50:18 > 2018 -0500 > @@ -89,7 +89,8 @@ > } > int defaultIndex; > struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)him; > - if (sin6->sin6_family == AF_INET6 && (sin6->sin6_scope_id == 0)) { > + if (sin6->sin6_family == AF_INET6 && (sin6->sin6_scope_id == 0) && > + (IN6_IS_ADDR_LINKLOCAL(&sin6->sin6_addr) || > IN6_IS_ADDR_MULTICAST(&sin6->sin6_addr))) { > defaultIndex = (*env)->GetStaticIntField(env, ni_class, > ni_defaultIndexID); > sin6->sin6_scope_id = defaultIndex; > > > Thanks, > Joel
