[PATCH iproute2 1/1] tc: Fix binding of gact action by index.

[PATCH iproute2 1/1] tc: Fix binding of gact action by index.

[Roman Mashak]

The following operation fails:
% sudo tc actions add action pipe index 1
% sudo tc filter add dev lo parent ffff: \
       protocol ip pref 10 u32 match ip src 127.0.0.2 \
       flowid 1:10 action gact index 1

Bad action type index
Usage: ... gact <ACTION> [RAND] [INDEX]
Where:  ACTION := reclassify | drop | continue | pass | pipe |
                  goto chain <CHAIN_INDEX> | jump <JUMP_COUNT>
        RAND := random <RANDTYPE> <ACTION> <VAL>
        RANDTYPE := netrand | determ
        VAL : = value not exceeding 10000
        JUMP_COUNT := Absolute jump from start of action list
        INDEX := index value used

However, passing a control action of gact rule during filter binding works:

% sudo tc filter add dev lo parent ffff: \
       protocol ip pref 10 u32 match ip src 127.0.0.2 \
       flowid 1:10 action gact pipe index 1

Binding by reference, i.e. by index, has to consistently work with
any tc action.

Since tc is sensitive to the order of keywords passed on the command line,
we can teach gact to skip parsing arguments as soon as it sees 'gact'
followed by 'index' keyword. 

Signed-off-by: Roman Mashak <mrv@mojatatu.com>
---
 tc/m_gact.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/tc/m_gact.c b/tc/m_gact.c
index a0a3c33d23da..5b781e16446d 100644
--- a/tc/m_gact.c
+++ b/tc/m_gact.c
@@ -89,6 +89,9 @@ parse_gact(struct action_util *a, int *argc_p, char ***argv_p,
 
 	if (!matches(*argv, "gact"))
 		NEXT_ARG_FWD();
+	/* we're binding existing gact action to filter by index. */
+	if (!matches(*argv, "index"))
+		goto skip_args;
 	if (parse_action_control(&argc, &argv, &p.action, false))
 		usage();	/* does not return */
 
@@ -133,6 +136,7 @@ parse_gact(struct action_util *a, int *argc_p, char ***argv_p,
 
 	if (argc > 0) {
 		if (matches(*argv, "index") == 0) {
+skip_args:
 			NEXT_ARG();
 			if (get_u32(&p.index, *argv, 10)) {
 				fprintf(stderr, "Illegal \"index\"\n");
-- 
2.7.4

Re: [PATCH iproute2 1/1] tc: Fix binding of gact action by index.

[Stephen Hemminger]

On Thu,  6 Jun 2019 17:32:09 -0400
Roman Mashak <mrv@mojatatu.com> wrote:

> The following operation fails:
> % sudo tc actions add action pipe index 1
> % sudo tc filter add dev lo parent ffff: \
>        protocol ip pref 10 u32 match ip src 127.0.0.2 \
>        flowid 1:10 action gact index 1
> 
> Bad action type index
> Usage: ... gact <ACTION> [RAND] [INDEX]
> Where:  ACTION := reclassify | drop | continue | pass | pipe |
>                   goto chain <CHAIN_INDEX> | jump <JUMP_COUNT>
>         RAND := random <RANDTYPE> <ACTION> <VAL>
>         RANDTYPE := netrand | determ
>         VAL : = value not exceeding 10000
>         JUMP_COUNT := Absolute jump from start of action list
>         INDEX := index value used
> 
> However, passing a control action of gact rule during filter binding works:
> 
> % sudo tc filter add dev lo parent ffff: \
>        protocol ip pref 10 u32 match ip src 127.0.0.2 \
>        flowid 1:10 action gact pipe index 1
> 
> Binding by reference, i.e. by index, has to consistently work with
> any tc action.
> 
> Since tc is sensitive to the order of keywords passed on the command line,
> we can teach gact to skip parsing arguments as soon as it sees 'gact'
> followed by 'index' keyword. 
> 
> Signed-off-by: Roman Mashak <mrv@mojatatu.com>
> ---

Applied

Re: [PATCH iproute2 1/1] tc: Fix binding of gact action by index.

[Stephen Hemminger]

On Thu,  6 Jun 2019 17:32:09 -0400
Roman Mashak <mrv@mojatatu.com> wrote:

> The following operation fails:
> % sudo tc actions add action pipe index 1
> % sudo tc filter add dev lo parent ffff: \
>        protocol ip pref 10 u32 match ip src 127.0.0.2 \
>        flowid 1:10 action gact index 1
> 
> Bad action type index
> Usage: ... gact <ACTION> [RAND] [INDEX]
> Where:  ACTION := reclassify | drop | continue | pass | pipe |
>                   goto chain <CHAIN_INDEX> | jump <JUMP_COUNT>
>         RAND := random <RANDTYPE> <ACTION> <VAL>
>         RANDTYPE := netrand | determ
>         VAL : = value not exceeding 10000
>         JUMP_COUNT := Absolute jump from start of action list
>         INDEX := index value used
> 
> However, passing a control action of gact rule during filter binding works:
> 
> % sudo tc filter add dev lo parent ffff: \
>        protocol ip pref 10 u32 match ip src 127.0.0.2 \
>        flowid 1:10 action gact pipe index 1
> 
> Binding by reference, i.e. by index, has to consistently work with
> any tc action.
> 
> Since tc is sensitive to the order of keywords passed on the command line,
> we can teach gact to skip parsing arguments as soon as it sees 'gact'
> followed by 'index' keyword. 
> 
> Signed-off-by: Roman Mashak <mrv@mojatatu.com>

Applied