From d71fa5c9763c24dd997a2fa4feb7a13a95bab42c Mon Sep 17 00:00:00 2001 From: Alexei Starovoitov Date: Tue, 18 Aug 2020 21:27:58 -0700 Subject: bpf: Add kernel module with user mode driver that populates bpffs. Add kernel module with user mode driver that populates bpffs with BPF iterators. $ mount bpffs /my/bpffs/ -t bpf $ ls -la /my/bpffs/ total 4 drwxrwxrwt 2 root root 0 Jul 2 00:27 . drwxr-xr-x 19 root root 4096 Jul 2 00:09 .. -rw------- 1 root root 0 Jul 2 00:27 maps.debug -rw------- 1 root root 0 Jul 2 00:27 progs.debug The user mode driver will load BPF Type Formats, create BPF maps, populate BPF maps, load two BPF programs, attach them to BPF iterators, and finally send two bpf_link IDs back to the kernel. The kernel will pin two bpf_links into newly mounted bpffs instance under names "progs.debug" and "maps.debug". These two files become human readable. $ cat /my/bpffs/progs.debug id name attached 11 dump_bpf_map bpf_iter_bpf_map 12 dump_bpf_prog bpf_iter_bpf_prog 27 test_pkt_access 32 test_main test_pkt_access test_pkt_access 33 test_subprog1 test_pkt_access_subprog1 test_pkt_access 34 test_subprog2 test_pkt_access_subprog2 test_pkt_access 35 test_subprog3 test_pkt_access_subprog3 test_pkt_access 36 new_get_skb_len get_skb_len test_pkt_access 37 new_get_skb_ifindex get_skb_ifindex test_pkt_access 38 new_get_constant get_constant test_pkt_access The BPF program dump_bpf_prog() in iterators.bpf.c is printing this data about all BPF programs currently loaded in the system. This information is unstable and will change from kernel to kernel as ".debug" suffix conveys. Signed-off-by: Alexei Starovoitov Signed-off-by: Daniel Borkmann Link: https://lore.kernel.org/bpf/20200819042759.51280-4-alexei.starovoitov@gmail.com --- net/bpfilter/Kconfig | 1 + 1 file changed, 1 insertion(+) (limited to 'net/bpfilter') diff --git a/net/bpfilter/Kconfig b/net/bpfilter/Kconfig index 73d0b12789f1..8ad0233ce497 100644 --- a/net/bpfilter/Kconfig +++ b/net/bpfilter/Kconfig @@ -2,6 +2,7 @@ menuconfig BPFILTER bool "BPF based packet filtering framework (BPFILTER)" depends on NET && BPF && INET + select USERMODE_DRIVER help This builds experimental bpfilter framework that is aiming to provide netfilter compatible functionality via BPF -- cgit v1.2.3-58-ga151