1. 15 Jun, 2012 3 commits
    • David S. Miller's avatar
    • David S. Miller's avatar
      ipv6: Handle PMTU in ICMP error handlers. · 81aded24
      David S. Miller authored
      One tricky issue on the ipv6 side vs. ipv4 is that the ICMP callouts
      to handle the error pass the 32-bit info cookie in network byte order
      whereas ipv4 passes it around in host byte order.
      
      Like the ipv4 side, we have two helper functions.  One for when we
      have a socket context and one for when we do not.
      
      ip6ip6 tunnels are not handled here, because they handle PMTU events
      by essentially relaying another ICMP packet-too-big message back to
      the original sender.
      
      This patch allows us to get rid of rt6_do_pmtu_disc().  It handles all
      kinds of situations that simply cannot happen when we do the PMTU
      update directly using a fully resolved route.
      
      In fact, the "plen == 128" check in ip6_rt_update_pmtu() can very
      likely be removed or changed into a BUG_ON() check.  We should never
      have a prefixed ipv6 route when we get there.
      
      Another piece of strange history here is that TCP and DCCP, unlike in
      ipv4, never invoke the update_pmtu() method from their ICMP error
      handlers.  This is incredibly astonishing since this is the context
      where we have the most accurate context in which to make a PMTU
      update, namely we have a fully connected socket and associated cached
      socket route.
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      81aded24
    • David S. Miller's avatar
      ipv4: Handle PMTU in all ICMP error handlers. · 36393395
      David S. Miller authored
      With ip_rt_frag_needed() removed, we have to explicitly update PMTU
      information in every ICMP error handler.
      
      Create two helper functions to facilitate this.
      
      1) ipv4_sk_update_pmtu()
      
         This updates the PMTU when we have a socket context to
         work with.
      
      2) ipv4_update_pmtu()
      
         Raw version, used when no socket context is available.  For this
         interface, we essentially just pass in explicit arguments for
         the flow identity information we would have extracted from the
         socket.
      
         And you'll notice that ipv4_sk_update_pmtu() is simply implemented
         in terms of ipv4_update_pmtu()
      
      Note that __ip_route_output_key() is used, rather than something like
      ip_route_output_flow() or ip_route_output_key().  This is because we
      absolutely do not want to end up with a route that does IPSEC
      encapsulation and the like.  Instead, we only want the route that
      would get us to the node described by the outermost IP header.
      Reported-by: default avatarSteffen Klassert <steffen.klassert@secunet.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      36393395
  2. 14 Jun, 2012 8 commits
  3. 13 Jun, 2012 19 commits
  4. 12 Jun, 2012 6 commits
  5. 11 Jun, 2012 4 commits