Yureka Lilian <yureka@cyberchaos.dev> writes:
The xdp-forwarder's purpose is implementing the functionality needed within the net-vm (a VM running the Linux drivers for any physical interfaces on the spectrum system).
In the future, the net-vm will load the included XDP programs on the passed-through physical interfaces as well as the downstream virtio interface going into the router (recognized by its special MAC address).
The net-vm needs to multiplex between the physical interfaces, as there might be several interfaces in the same IOMMU-group.
For this, the XDP program loaded on the physical interfaces (`prog_physical.o`) applies a VLAN tag corresponding to the interface id and redirects the packets to the router interface (identified by the `router_iface` bpf map). In the other direction the XDP program loaded on the router interface (`prog_router.o`) removes one layer of VLAN tagging and redirects the packets to the interface read from the VLAN tag.
The helper program `set_router_iface` is used to update the `router_iface` bpf map to point to the interface passed as argument to the program.
Co-authored-by: Demi Marie Obenour <demiobenour@gmail.com> Signed-off-by: Yureka Lilian <yureka@cyberchaos.dev> --- pkgs/default.nix | 4 + release/checks/pkg-tests.nix | 1 + tools/default.nix | 15 +- tools/meson.build | 4 + tools/meson_options.txt | 3 + tools/xdp-forwarder/include/parsing_helpers.h | 274 ++++++++++++++++++ tools/xdp-forwarder/include/rewrite_helpers.h | 146 ++++++++++ tools/xdp-forwarder/meson.build | 48 +++ tools/xdp-forwarder/prog_physical.c | 39 +++ tools/xdp-forwarder/prog_router.c | 43 +++ tools/xdp-forwarder/set_router_iface.c | 30 ++ 11 files changed, 604 insertions(+), 3 deletions(-) create mode 100644 tools/xdp-forwarder/include/parsing_helpers.h create mode 100644 tools/xdp-forwarder/include/rewrite_helpers.h create mode 100644 tools/xdp-forwarder/meson.build create mode 100644 tools/xdp-forwarder/prog_physical.c create mode 100644 tools/xdp-forwarder/prog_router.c create mode 100644 tools/xdp-forwarder/set_router_iface.c
release/checks/pkg-tests.nix fails with this patch applied, because clang-tidy can't find headers. I'm happy to look into why that is, but if you feel like having a look or already know what's happening, please let me know!