04 Apr, 2010

6 commits

  • The existing pppol2tp driver exports debug info to
    /proc/net/pppol2tp. Rather than adding info to that file for the new
    functionality added in this patch series, we add new files in debugfs,
    leaving the old /proc file for backwards compatibility (L2TPv2 only).

    Currently only one file is provided: l2tp/tunnels, which lists
    internal debug info for all l2tp tunnels and sessions. More files may
    be added later. The info is for debug and problem analysis only -
    userspace apps should use netlink to obtain status about l2tp tunnels
    and sessions.

    Although debugfs does not support net namespaces, the tunnels and
    sessions dumped in l2tp/tunnels are only those in the net namespace of
    the process reading the file.

    Signed-off-by: James Chapman
    Signed-off-by: David S. Miller

    James Chapman
     
  • This driver presents a regular net_device for each L2TP ethernet
    pseudowire instance. These interfaces are named l2tpethN by default,
    though userspace can specify an alternative name when the L2TP
    session is created, if preferred. When the pseudowire is established,
    regular Linux networking utilities may be used to configure the
    interface, i.e. give it IP address info or add it to a bridge. Any
    data passed over the interface is carried over an L2TP tunnel.

    Signed-off-by: James Chapman
    Reviewed-by: Randy Dunlap
    Signed-off-by: David S. Miller

    James Chapman
     
  • In L2TPv3, we need to create/delete/modify/query L2TP tunnel and
    session contexts. The number of parameters is significant. So let's
    use netlink. Userspace uses this API to control L2TP tunnel/session
    contexts in the kernel.

    The previous pppol2tp driver was managed using [gs]etsockopt(). This
    API is retained for backwards compatibility. Unlike L2TPv2 which
    carries only PPP frames, L2TPv3 can carry raw ethernet frames or other
    frame types and these do not always have an associated socket
    family. Therefore, we need a way to use L2TP sessions that doesn't
    require a socket type for each supported frame type. Hence netlink is
    used.

    Signed-off-by: James Chapman
    Reviewed-by: Randy Dunlap
    Signed-off-by: David S. Miller

    James Chapman
     
  • This patch adds a new L2TPIP socket family and modifies the core to
    handle the case where there is no UDP header in the L2TP
    packet. L2TP/IP uses IP protocol 115. Since L2TP/UDP and L2TP/IP
    packets differ in layout, the datapath packet handling code needs
    changes too. Userspace uses an L2TPIP socket instead of a UDP socket
    when IP encapsulation is required.

    We can't use raw sockets for this because the semantics of raw sockets
    don't lend themselves to the socket-per-tunnel model - we need to

    Signed-off-by: David S. Miller

    James Chapman
     
  • This patch splits the pppol2tp driver into separate L2TP and PPP parts
    to prepare for L2TPv3 support. In L2TPv3, protocols other than PPP can
    be carried, so this split creates a common L2TP core that will handle
    the common L2TP bits which protocol support modules such as PPP will
    use.

    Note that the existing pppol2tp module is split into l2tp_core and
    l2tp_ppp by this change.

    There are no feature changes here. Internally, however, there are
    significant changes, mostly to handle the separation of PPP-specific
    data from the L2TP session and to provide hooks in the core for
    modules like PPP to access.

    Signed-off-by: James Chapman
    Reviewed-by: Randy Dunlap
    Signed-off-by: David S. Miller

    James Chapman
     
  • This patch moves the existing pppol2tp driver from drivers/net into a
    new net/l2tp directory, which is where the upcoming L2TPv3 code will
    live. The existing CONFIG_PPPOL2TP config option is left in its
    current place to avoid "make oldconfig" issues when an existing
    pppol2tp user takes this change. (This is the same approach used for
    the pppoatm driver, which moved to net/atm.)

    There are no code changes. The existing drivers/net/pppol2tp.c is
    simply moved to net/l2tp.

    Signed-off-by: James Chapman
    Reviewed-by: Randy Dunlap
    Signed-off-by: David S. Miller

    James Chapman