Andrey Ignatov aac3fc320d bpf: Post-hooks for sys_bind ... "Post-hooks" are hooks that are called right before returning from sys_bind. At this time IP and port are already allocated and no further changes to `struct sock` can happen before returning from sys_bind but BPF program has a chance to inspect the socket and change sys_bind result. Specifically it can e.g. inspect what port was allocated and if it doesn't satisfy some policy, BPF program can force sys_bind to fail and return EPERM to user. Another example of usage is recording the IP:port pair to some map to use it in later calls to sys_connect. E.g. if some TCP server inside cgroup was bound to some IP:port_n, it can be recorded to a map. And later when some TCP client inside same cgroup is trying to connect to 127.0.0.1:port_n, BPF hook for sys_connect can override the destination and connect application to IP:port_n instead of 127.0.0.1:port_n. That helps forcing all applications inside a cgroup to use desired IP and not break those applications if they e.g. use localhost to communicate between each other. == Implementation details == Post-hooks are implemented as two new attach types `BPF_CGROUP_INET4_POST_BIND` and `BPF_CGROUP_INET6_POST_BIND` for existing prog type `BPF_PROG_TYPE_CGROUP_SOCK`. Separate attach types for IPv4 and IPv6 are introduced to avoid access to IPv6 field in `struct sock` from `inet_bind()` and to IPv4 field from `inet6_bind()` since those fields might not make sense in such cases. Signed-off-by: Andrey Ignatov <rdna@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>		2018-03-31 02:16:26 +02:00
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arraymap.c	bpf: add schedule points in percpu arrays management	2018-02-22 21:27:06 +01:00
bpf_lru_list.c	bpf: lru: Lower the PERCPU_NR_SCANS from 16 to 4	2017-04-17 13:55:52 -04:00
bpf_lru_list.h	bpf: Only set node->ref = 1 if it has not been set	2017-09-01 09:57:39 -07:00
cgroup.c	bpf: Hooks for sys_bind	2018-03-31 02:15:18 +02:00
core.c	bpf: fix bpf_prog_array_copy_to_user warning from perf event prog query	2018-02-14 08:59:37 -08:00
cpumap.c	bpf: cpumap: use GFP_KERNEL instead of GFP_ATOMIC in __cpu_map_entry_alloc()	2018-02-14 15:34:27 +01:00
devmap.c	bpf: add helper for copying attrs to struct bpf_map	2018-01-14 23:36:29 +01:00
disasm.c	bpf: Remove struct bpf_verifier_env argument from print_bpf_insn	2018-03-23 17:38:57 +01:00
disasm.h	bpf: Remove struct bpf_verifier_env argument from print_bpf_insn	2018-03-23 17:38:57 +01:00
hashtab.c	bpf: add helper for copying attrs to struct bpf_map	2018-01-14 23:36:29 +01:00
helpers.c	bpf: rename ARG_PTR_TO_STACK	2017-01-09 16:56:27 -05:00
inode.c	bpf: comment why dots in filenames under BPF virtual FS are not allowed	2018-03-09 10:30:30 +01:00
lpm_trie.c	bpf: fix rcu lockdep warning for lpm_trie map_free callback	2018-02-22 21:29:12 +01:00
Makefile	bpf: only build sockmap with CONFIG_INET	2018-01-04 19:01:14 +01:00
map_in_map.c	bpf: Add syscall lookup support for fd array and htab	2017-06-29 13:13:25 -04:00
map_in_map.h	bpf: Add syscall lookup support for fd array and htab	2017-06-29 13:13:25 -04:00
offload.c	bpf: offload: report device information about offloaded maps	2018-01-18 22:54:25 +01:00
percpu_freelist.c	bpf: fix lockdep splat	2017-11-15 19:46:32 +09:00
percpu_freelist.h
sockmap.c	bpf: sockmap: initialize sg table entries properly	2018-03-30 22:50:15 +02:00
stackmap.c	bpf: extend stackmap to save binary_build_id+offset instead of address	2018-03-15 01:09:28 +01:00
syscall.c	bpf: Post-hooks for sys_bind	2018-03-31 02:16:26 +02:00
tnum.c	bpf/verifier: track signed and unsigned min/max values	2017-08-08 17:51:34 -07:00
verifier.c	bpf: Hooks for sys_bind	2018-03-31 02:15:18 +02:00