From fca59bea770346cf1c1f9b0e00cb48a61b44a8f3 Mon Sep 17 00:00:00 2001 From: Harald Welte Date: Sun, 25 Oct 2015 21:00:20 +0100 Subject: import of old now defunct presentation slides svn repo --- 2005/ipv6-astaro2005/astaro-topics | 41 ++++++++++++++++++++++++++++++++++++++ 1 file changed, 41 insertions(+) create mode 100644 2005/ipv6-astaro2005/astaro-topics (limited to '2005/ipv6-astaro2005/astaro-topics') diff --git a/2005/ipv6-astaro2005/astaro-topics b/2005/ipv6-astaro2005/astaro-topics new file mode 100644 index 0000000..310deca --- /dev/null +++ b/2005/ipv6-astaro2005/astaro-topics @@ -0,0 +1,41 @@ +Details of stateless autoconfiguration + address space is split in two 64bit halves + upper 64bit are used to specify a particular network segment + lower 64bit are used for individual nodes in one segment + lower 64bit are generated from 48bit mac address with 'fffe' in the middle + potential problem: privacy + +DNS and IPv6 + forward resolval (hostname -> address) + ipv4 uses 'IN A' record + ipv6 uses 'IN AAAA' record + a particular hostname can have A and AAAA records + reverse resolval + uses .ip6.arpa. suffix + uses hexadecimal instead of decimal notation: + 4.4.0.0.0.0.0.0.0.8.7.0.1.0.0.2.ip6.arpa. + portable applications under *BSD/Linux do round-robin between all records, with a preference of ipv6 for the first try. + +BSD Sockets API and IPv6 + struct in_addr has become in6_addr + new API's like getaddrinfo() instead of gethostbyname() support _both_ ipv4 and ipv6 + apart from that, everything is the same. + +configuration under linux + router/gateway + runs radvd or zebra for sending router advertisements + client + just has to load 'ipv6' module and configure an interface up + recevies prefix-advertisement(s) and auto-configures address accordingly + +IPv6 specific security issues + packet filter has to explicitly allow neighbour discovery, since it's inside ipv6/icmpv6 + special attention to option headers + most sites won't want routing or hop-by-hop options + neighbour cache DoS: + compare with existing neighbour cache issues in large (/16) networks + in ipv6, the standard is /64 for every segment (!) + + one advantage: port scanning of whole networks way more difficult :) + + -- cgit v1.2.3