| Message ID | 20201202103923.12447-1-mariuszx.dudek@intel.com (mailing list archive) |
|---|---|
| Headers | show |
| Series | libbpf: add support for privileged/unprivileged control separation | expand |
On Wed, Dec 2, 2020 at 2:39 AM <mariusz.dudek@gmail.com> wrote: > > From: Mariusz Dudek <mariuszx.dudek@intel.com> > > This patch series adds support for separation of eBPF program > load and xsk socket creation. In for example a Kubernetes > environment you can have an AF_XDP CNI or daemonset that is > responsible for launching pods that execute an application > using AF_XDP sockets. It is desirable that the pod runs with > as low privileges as possible, CAP_NET_RAW in this case, > and that all operations that require privileges are contained > in the CNI or daemonset. > > In this case, you have to be able separate ePBF program load from > xsk socket creation. > > Currently, this will not work with the xsk_socket__create APIs > because you need to have CAP_NET_ADMIN privileges to load eBPF > program and CAP_SYS_ADMIN privileges to create update xsk_bpf_maps. > To be exact xsk_set_bpf_maps does not need those privileges but > it takes the prog_fd and xsks_map_fd and those are known only to > process that was loading eBPF program. The api bpf_prog_get_fd_by_id > that looks up the fd of the prog using an prog_id and > bpf_map_get_fd_by_id that looks for xsks_map_fd usinb map_id both > requires CAP_SYS_ADMIN. > > With this patch, the pod can be run with CAP_NET_RAW capability > only. In case your umem is larger or equal process limit for > MEMLOCK you need either increase the limit or CAP_IPC_LOCK capability. > Without this patch in case of insufficient rights ENOPERM is > returned by xsk_socket__create. > > To resolve this privileges issue two new APIs are introduced: > - xsk_setup_xdp_prog - loads the built in XDP program. It can > also return xsks_map_fd which is needed by unprivileged > process to update xsks_map with AF_XDP socket "fd" > - xsk_sokcet__update_xskmap - inserts an AF_XDP socket into an > xskmap for a particular xsk_socket > > Usage example: > int xsk_setup_xdp_prog(int ifindex, int *xsks_map_fd) > > int xsk_socket__update_xskmap(struct xsk_socket *xsk, int xsks_map_fd); > > Inserts AF_XDP socket "fd" into the xskmap. > > The first patch introduces the new APIs. The second patch provides > a new sample applications working as control and modification to > existing xdpsock application to work with less privileges. > > This patch set is based on bpf-next commit ba0581749fec > (net, xdp, xsk: fix __sk_mark_napi_id_once napi_id error) > > Since v5 > - fixed sample/bpf/xdpsock_user.c to resolve merge conflicts > > Since v4 > - sample/bpf/Makefile issues fixed > > Since v3: > - force_set_map flag removed > - leaking of xsk struct fixed > - unified function error returning policy implemented > > Since v2: > - new APIs moved itto LIBBPF_0.3.0 section > - struct bpf_prog_cfg_opts removed > - loading own eBPF program via xsk_setup_xdp_prog functionality removed > > Since v1: > - struct bpf_prog_cfg improved for backward/forward compatibility > - API xsk_update_xskmap renamed to xsk_socket__update_xskmap > - commit message formatting fixed > > Mariusz Dudek (2): > libbpf: separate XDP program load with xsk socket creation > samples/bpf: sample application for eBPF load and socket creation > split > > samples/bpf/Makefile | 4 +- > samples/bpf/xdpsock.h | 8 ++ > samples/bpf/xdpsock_ctrl_proc.c | 187 ++++++++++++++++++++++++++++++++ > samples/bpf/xdpsock_user.c | 146 +++++++++++++++++++++++-- > tools/lib/bpf/libbpf.map | 2 + > tools/lib/bpf/xsk.c | 92 ++++++++++++++-- > tools/lib/bpf/xsk.h | 5 + > 7 files changed, 425 insertions(+), 19 deletions(-) > create mode 100644 samples/bpf/xdpsock_ctrl_proc.c > > -- > 2.20.1 > Applied to bpf-next. For the future, please carry over Acked-by you got, thanks. I've added Magnus's ones back.
Hello: This series was applied to bpf/bpf-next.git (refs/heads/master): On Wed, 2 Dec 2020 11:39:21 +0100 you wrote: > From: Mariusz Dudek <mariuszx.dudek@intel.com> > > This patch series adds support for separation of eBPF program > load and xsk socket creation. In for example a Kubernetes > environment you can have an AF_XDP CNI or daemonset that is > responsible for launching pods that execute an application > using AF_XDP sockets. It is desirable that the pod runs with > as low privileges as possible, CAP_NET_RAW in this case, > and that all operations that require privileges are contained > in the CNI or daemonset. > > [...] Here is the summary with links: - [v6,bpf-next,1/2] libbpf: separate XDP program load with xsk socket creation https://git.kernel.org/bpf/bpf-next/c/56ab028af72b - [v6,bpf-next,2/2] samples/bpf: sample application for eBPF load and socket creation split https://git.kernel.org/bpf/bpf-next/c/d6482b4367ac You are awesome, thank you! -- Deet-doot-dot, I am a bot. https://korg.docs.kernel.org/patchwork/pwbot.html
From: Mariusz Dudek <mariuszx.dudek@intel.com> This patch series adds support for separation of eBPF program load and xsk socket creation. In for example a Kubernetes environment you can have an AF_XDP CNI or daemonset that is responsible for launching pods that execute an application using AF_XDP sockets. It is desirable that the pod runs with as low privileges as possible, CAP_NET_RAW in this case, and that all operations that require privileges are contained in the CNI or daemonset. In this case, you have to be able separate ePBF program load from xsk socket creation. Currently, this will not work with the xsk_socket__create APIs because you need to have CAP_NET_ADMIN privileges to load eBPF program and CAP_SYS_ADMIN privileges to create update xsk_bpf_maps. To be exact xsk_set_bpf_maps does not need those privileges but it takes the prog_fd and xsks_map_fd and those are known only to process that was loading eBPF program. The api bpf_prog_get_fd_by_id that looks up the fd of the prog using an prog_id and bpf_map_get_fd_by_id that looks for xsks_map_fd usinb map_id both requires CAP_SYS_ADMIN. With this patch, the pod can be run with CAP_NET_RAW capability only. In case your umem is larger or equal process limit for MEMLOCK you need either increase the limit or CAP_IPC_LOCK capability. Without this patch in case of insufficient rights ENOPERM is returned by xsk_socket__create. To resolve this privileges issue two new APIs are introduced: - xsk_setup_xdp_prog - loads the built in XDP program. It can also return xsks_map_fd which is needed by unprivileged process to update xsks_map with AF_XDP socket "fd" - xsk_sokcet__update_xskmap - inserts an AF_XDP socket into an xskmap for a particular xsk_socket Usage example: int xsk_setup_xdp_prog(int ifindex, int *xsks_map_fd) int xsk_socket__update_xskmap(struct xsk_socket *xsk, int xsks_map_fd); Inserts AF_XDP socket "fd" into the xskmap. The first patch introduces the new APIs. The second patch provides a new sample applications working as control and modification to existing xdpsock application to work with less privileges. This patch set is based on bpf-next commit ba0581749fec (net, xdp, xsk: fix __sk_mark_napi_id_once napi_id error) Since v5 - fixed sample/bpf/xdpsock_user.c to resolve merge conflicts Since v4 - sample/bpf/Makefile issues fixed Since v3: - force_set_map flag removed - leaking of xsk struct fixed - unified function error returning policy implemented Since v2: - new APIs moved itto LIBBPF_0.3.0 section - struct bpf_prog_cfg_opts removed - loading own eBPF program via xsk_setup_xdp_prog functionality removed Since v1: - struct bpf_prog_cfg improved for backward/forward compatibility - API xsk_update_xskmap renamed to xsk_socket__update_xskmap - commit message formatting fixed Mariusz Dudek (2): libbpf: separate XDP program load with xsk socket creation samples/bpf: sample application for eBPF load and socket creation split samples/bpf/Makefile | 4 +- samples/bpf/xdpsock.h | 8 ++ samples/bpf/xdpsock_ctrl_proc.c | 187 ++++++++++++++++++++++++++++++++ samples/bpf/xdpsock_user.c | 146 +++++++++++++++++++++++-- tools/lib/bpf/libbpf.map | 2 + tools/lib/bpf/xsk.c | 92 ++++++++++++++-- tools/lib/bpf/xsk.h | 5 + 7 files changed, 425 insertions(+), 19 deletions(-) create mode 100644 samples/bpf/xdpsock_ctrl_proc.c