Adding upstream version 6.6.15.upstream/6.6.15

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 58 insertions, 0 deletions

diff --git a/Documentation/networking/bareudp.rst b/Documentation/networking/bareudp.rst
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+.. SPDX-License-Identifier: GPL-2.0
+
+========================================
+Bare UDP Tunnelling Module Documentation
+========================================
+
+There are various L3 encapsulation standards using UDP being discussed to
+leverage the UDP based load balancing capability of different networks.
+MPLSoUDP (__ https://tools.ietf.org/html/rfc7510) is one among them.
+
+The Bareudp tunnel module provides a generic L3 encapsulation support for
+tunnelling different L3 protocols like MPLS, IP, NSH etc. inside a UDP tunnel.
+
+Special Handling
+----------------
+The bareudp device supports special handling for MPLS & IP as they can have
+multiple ethertypes.
+MPLS procotcol can have ethertypes ETH_P_MPLS_UC  (unicast) & ETH_P_MPLS_MC (multicast).
+IP protocol can have ethertypes ETH_P_IP (v4) & ETH_P_IPV6 (v6).
+This special handling can be enabled only for ethertypes ETH_P_IP & ETH_P_MPLS_UC
+with a flag called multiproto mode.
+
+Usage
+------
+
+1) Device creation & deletion
+
+    a) ip link add dev bareudp0 type bareudp dstport 6635 ethertype mpls_uc
+
+       This creates a bareudp tunnel device which tunnels L3 traffic with ethertype
+       0x8847 (MPLS traffic). The destination port of the UDP header will be set to
+       6635.The device will listen on UDP port 6635 to receive traffic.
+
+    b) ip link delete bareudp0
+
+2) Device creation with multiproto mode enabled
+
+The multiproto mode allows bareudp tunnels to handle several protocols of the
+same family. It is currently only available for IP and MPLS. This mode has to
+be enabled explicitly with the "multiproto" flag.
+
+    a) ip link add dev bareudp0 type bareudp dstport 6635 ethertype ipv4 multiproto
+
+       For an IPv4 tunnel the multiproto mode allows the tunnel to also handle
+       IPv6.
+
+    b) ip link add dev bareudp0 type bareudp dstport 6635 ethertype mpls_uc multiproto
+
+       For MPLS, the multiproto mode allows the tunnel to handle both unicast
+       and multicast MPLS packets.
+
+3) Device Usage
+
+The bareudp device could be used along with OVS or flower filter in TC.
+The OVS or TC flower layer must set the tunnel information in SKB dst field before
+sending packet buffer to the bareudp device for transmission. On reception the
+bareudp device extracts and stores the tunnel information in SKB dst field before
+passing the packet buffer to the network stack.