bpftool: support loading flow dissector

This commit adds support for loading/attaching/detaching flow
dissector program.

When `bpftool loadall` is called with a flow_dissector prog (i.e. when the
'type flow_dissector' argument is passed), we load and pin all programs.
User is responsible to construct the jump table for the tail calls.

The last argument of `bpftool attach` is made optional for this use
case.

Example:
bpftool prog load tools/testing/selftests/bpf/bpf_flow.o \
        /sys/fs/bpf/flow type flow_dissector \
	pinmaps /sys/fs/bpf/flow

bpftool map update pinned /sys/fs/bpf/flow/jmp_table \
        key 0 0 0 0 \
        value pinned /sys/fs/bpf/flow/IP

bpftool map update pinned /sys/fs/bpf/flow/jmp_table \
        key 1 0 0 0 \
        value pinned /sys/fs/bpf/flow/IPV6

bpftool map update pinned /sys/fs/bpf/flow/jmp_table \
        key 2 0 0 0 \
        value pinned /sys/fs/bpf/flow/IPV6OP

bpftool map update pinned /sys/fs/bpf/flow/jmp_table \
        key 3 0 0 0 \
        value pinned /sys/fs/bpf/flow/IPV6FR

bpftool map update pinned /sys/fs/bpf/flow/jmp_table \
        key 4 0 0 0 \
        value pinned /sys/fs/bpf/flow/MPLS

bpftool map update pinned /sys/fs/bpf/flow/jmp_table \
        key 5 0 0 0 \
        value pinned /sys/fs/bpf/flow/VLAN

bpftool prog attach pinned /sys/fs/bpf/flow/flow_dissector flow_dissector

Tested by using the above lines to load the prog in
the test_flow_dissector.sh selftest.

Signed-off-by: Stanislav Fomichev <sdf@google.com>
Acked-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
This commit is contained in:
Stanislav Fomichev 2018-11-09 08:21:46 -08:00 committed by Alexei Starovoitov
parent 3767a94b32
commit 092f089273
3 changed files with 77 additions and 54 deletions

View File

@ -26,8 +26,8 @@ MAP COMMANDS
| **bpftool** **prog dump jited** *PROG* [{**file** *FILE* | **opcodes**}]
| **bpftool** **prog pin** *PROG* *FILE*
| **bpftool** **prog { load | loadall }** *OBJ* *PATH* [**type** *TYPE*] [**map** {**idx** *IDX* | **name** *NAME*} *MAP*] [**dev** *NAME*]
| **bpftool** **prog attach** *PROG* *ATTACH_TYPE* *MAP*
| **bpftool** **prog detach** *PROG* *ATTACH_TYPE* *MAP*
| **bpftool** **prog attach** *PROG* *ATTACH_TYPE* [*MAP*]
| **bpftool** **prog detach** *PROG* *ATTACH_TYPE* [*MAP*]
| **bpftool** **prog help**
|
| *MAP* := { **id** *MAP_ID* | **pinned** *FILE* }
@ -40,7 +40,9 @@ MAP COMMANDS
| **cgroup/bind4** | **cgroup/bind6** | **cgroup/post_bind4** | **cgroup/post_bind6** |
| **cgroup/connect4** | **cgroup/connect6** | **cgroup/sendmsg4** | **cgroup/sendmsg6**
| }
| *ATTACH_TYPE* := { **msg_verdict** | **skb_verdict** | **skb_parse** }
| *ATTACH_TYPE* := {
| **msg_verdict** | **skb_verdict** | **skb_parse** | **flow_dissector**
| }
DESCRIPTION
@ -103,13 +105,17 @@ DESCRIPTION
contain a dot character ('.'), which is reserved for future
extensions of *bpffs*.
**bpftool prog attach** *PROG* *ATTACH_TYPE* *MAP*
Attach bpf program *PROG* (with type specified by *ATTACH_TYPE*)
to the map *MAP*.
**bpftool prog attach** *PROG* *ATTACH_TYPE* [*MAP*]
Attach bpf program *PROG* (with type specified by
*ATTACH_TYPE*). Most *ATTACH_TYPEs* require a *MAP*
parameter, with the exception of *flow_dissector* which is
attached to current networking name space.
**bpftool prog detach** *PROG* *ATTACH_TYPE* *MAP*
Detach bpf program *PROG* (with type specified by *ATTACH_TYPE*)
from the map *MAP*.
**bpftool prog detach** *PROG* *ATTACH_TYPE* [*MAP*]
Detach bpf program *PROG* (with type specified by
*ATTACH_TYPE*). Most *ATTACH_TYPEs* require a *MAP*
parameter, with the exception of *flow_dissector* which is
detached from the current networking name space.
**bpftool prog help**
Print short help message.

View File

@ -299,7 +299,8 @@ _bpftool()
fi
if [[ ${#words[@]} == 6 ]]; then
COMPREPLY=( $( compgen -W "msg_verdict skb_verdict skb_parse" -- "$cur" ) )
COMPREPLY=( $( compgen -W "msg_verdict skb_verdict \
skb_parse flow_dissector" -- "$cur" ) )
return 0
fi
@ -338,7 +339,16 @@ _bpftool()
case $prev in
type)
COMPREPLY=( $( compgen -W "socket kprobe kretprobe classifier action tracepoint raw_tracepoint xdp perf_event cgroup/skb cgroup/sock cgroup/dev lwt_in lwt_out lwt_xmit lwt_seg6local sockops sk_skb sk_msg lirc_mode2 cgroup/bind4 cgroup/bind6 cgroup/connect4 cgroup/connect6 cgroup/sendmsg4 cgroup/sendmsg6 cgroup/post_bind4 cgroup/post_bind6" -- \
COMPREPLY=( $( compgen -W "socket kprobe \
kretprobe classifier flow_dissector \
action tracepoint raw_tracepoint \
xdp perf_event cgroup/skb cgroup/sock \
cgroup/dev lwt_in lwt_out lwt_xmit \
lwt_seg6local sockops sk_skb sk_msg \
lirc_mode2 cgroup/bind4 cgroup/bind6 \
cgroup/connect4 cgroup/connect6 \
cgroup/sendmsg4 cgroup/sendmsg6 \
cgroup/post_bind4 cgroup/post_bind6" -- \
"$cur" ) )
return 0
;;

View File

@ -81,6 +81,7 @@ static const char * const attach_type_strings[] = {
[BPF_SK_SKB_STREAM_PARSER] = "stream_parser",
[BPF_SK_SKB_STREAM_VERDICT] = "stream_verdict",
[BPF_SK_MSG_VERDICT] = "msg_verdict",
[BPF_FLOW_DISSECTOR] = "flow_dissector",
[__MAX_BPF_ATTACH_TYPE] = NULL,
};
@ -721,30 +722,49 @@ int map_replace_compar(const void *p1, const void *p2)
return a->idx - b->idx;
}
static int parse_attach_detach_args(int argc, char **argv, int *progfd,
enum bpf_attach_type *attach_type,
int *mapfd)
{
if (!REQ_ARGS(3))
return -EINVAL;
*progfd = prog_parse_fd(&argc, &argv);
if (*progfd < 0)
return *progfd;
*attach_type = parse_attach_type(*argv);
if (*attach_type == __MAX_BPF_ATTACH_TYPE) {
p_err("invalid attach/detach type");
return -EINVAL;
}
if (*attach_type == BPF_FLOW_DISSECTOR) {
*mapfd = -1;
return 0;
}
NEXT_ARG();
if (!REQ_ARGS(2))
return -EINVAL;
*mapfd = map_parse_fd(&argc, &argv);
if (*mapfd < 0)
return *mapfd;
return 0;
}
static int do_attach(int argc, char **argv)
{
enum bpf_attach_type attach_type;
int err, mapfd, progfd;
int err, progfd;
int mapfd;
if (!REQ_ARGS(5)) {
p_err("too few parameters for map attach");
return -EINVAL;
}
progfd = prog_parse_fd(&argc, &argv);
if (progfd < 0)
return progfd;
attach_type = parse_attach_type(*argv);
if (attach_type == __MAX_BPF_ATTACH_TYPE) {
p_err("invalid attach type");
return -EINVAL;
}
NEXT_ARG();
mapfd = map_parse_fd(&argc, &argv);
if (mapfd < 0)
return mapfd;
err = parse_attach_detach_args(argc, argv,
&progfd, &attach_type, &mapfd);
if (err)
return err;
err = bpf_prog_attach(progfd, mapfd, attach_type, 0);
if (err) {
@ -760,27 +780,13 @@ static int do_attach(int argc, char **argv)
static int do_detach(int argc, char **argv)
{
enum bpf_attach_type attach_type;
int err, mapfd, progfd;
int err, progfd;
int mapfd;
if (!REQ_ARGS(5)) {
p_err("too few parameters for map detach");
return -EINVAL;
}
progfd = prog_parse_fd(&argc, &argv);
if (progfd < 0)
return progfd;
attach_type = parse_attach_type(*argv);
if (attach_type == __MAX_BPF_ATTACH_TYPE) {
p_err("invalid attach type");
return -EINVAL;
}
NEXT_ARG();
mapfd = map_parse_fd(&argc, &argv);
if (mapfd < 0)
return mapfd;
err = parse_attach_detach_args(argc, argv,
&progfd, &attach_type, &mapfd);
if (err)
return err;
err = bpf_prog_detach2(progfd, mapfd, attach_type);
if (err) {
@ -1094,8 +1100,8 @@ static int do_help(int argc, char **argv)
" [type TYPE] [dev NAME] \\\n"
" [map { idx IDX | name NAME } MAP]\\\n"
" [pinmaps MAP_DIR]\n"
" %s %s attach PROG ATTACH_TYPE MAP\n"
" %s %s detach PROG ATTACH_TYPE MAP\n"
" %s %s attach PROG ATTACH_TYPE [MAP]\n"
" %s %s detach PROG ATTACH_TYPE [MAP]\n"
" %s %s help\n"
"\n"
" " HELP_SPEC_MAP "\n"
@ -1107,7 +1113,8 @@ static int do_help(int argc, char **argv)
" cgroup/bind4 | cgroup/bind6 | cgroup/post_bind4 |\n"
" cgroup/post_bind6 | cgroup/connect4 | cgroup/connect6 |\n"
" cgroup/sendmsg4 | cgroup/sendmsg6 }\n"
" ATTACH_TYPE := { msg_verdict | skb_verdict | skb_parse }\n"
" ATTACH_TYPE := { msg_verdict | skb_verdict | skb_parse |\n"
" flow_dissector }\n"
" " HELP_SPEC_OPTIONS "\n"
"",
bin_name, argv[-2], bin_name, argv[-2], bin_name, argv[-2],