flow_parser: add shared parser library

Add a global RSS type string table and helper functions to convert between RSS type names and values.
Add unit tests for RSS type helper.

Signed-off-by Lukas Sismis <[email protected]>

---

This series extracts the testpmd flow CLI parser into a reusable library, enabling external applications to parse rte_flow rules using testpmd syntax.

Motivation
----------
External applications like Suricata IDS [1] need to express hardware filtering rules in a consistent, human-readable format. Rather than inventing custom syntax, reusing testpmd's well-tested flow grammar provides immediate compatibility with existing documentation and user knowledge.

Note: This library provides only one way to create rte_flow structures. Applications can also construct rte_flow_attr, rte_flow_item[], and rte_flow_action[] directly in C code.

Design
------
The library (librte_flow_parser) exposes the following APIs:
- rte_flow_parser_parse_attr_str(): Parse attributes only
- rte_flow_parser_parse_pattern_str(): Parse patterns only
- rte_flow_parser_parse_actions_str(): Parse actions only

Testpmd is updated to use the library, ensuring a single maintained parser implementation.

Testing and Demo
-------
- Functional tests in dpdk-test
- Example application: examples/flow_parsing

Changes
-------
v10:
- rebased to avoid Github Actions CI build failure
- merge conflict solved in rel_notes/release_26_03.rst
- release notes shortened

v9:
- removed extra new line from the flow parser docs file

v8:
- rte_port/queue_id_t typedefs removal to be included in a separate patch series
- move of accidental changes of rte_flow parser library from the testpmd commit
- DynaNIC copyright name update

v7:
- Fixed implicit integer comparison (while (left) -> while (left != 0))
- NULL checks fixed
- arpa header removed for Windows compatibility
- minor comments from the last review addressed

v6:
- Inconsistent Experimental API Version adjusted
- Fixes Tag added to MSVC build commit
- Non-Standard Header Guards updated
- Implicit Pointer Comparison and Return Type issues addressed in many places
- commit message in patch 6 updated

v5:
- removed/replaced (f)printf code from the library
- reverted back to exporting the internal/private API as it is needed by testpmd and cannot be easily split further.
- adjusted length of certain lines
- marking port/queue id typedef as experimental
- updated release rel_notes
- copyeright adjustments

v4:
- ethdev changes in separate commit
- library's public API only exposes attribute, pattern and action parsing, while the full command parsing is kept internal for testpmd usage only.
- Addressed Stephen's comments from V3
- dpdk-test now have tests focused on public and internal library functions

v3:
- Add more functional tests
- More concise MAINTAINERS updates
- Updated license headers
- A thing to note: When playing with flow commands, I figured, some may use non-flow commands, such as raw decap/encap, policy meter and others. Flow parser library itself now supports set command to set e.g. the decap/ encap parameters, as the flow syntax only supports defining the index of the encap/decap configs. The library, however, does not support e.g. create command to create policy meters, as that is just an ID and it can be created separately using rte_meter APIs.

[1] https://github.com/OISF/suricata/pull/13950

Lukas Sismis (6):
cmdline: include stddef.h for MSVC compatibility
ethdev: add RSS type helper APIs
flow_parser: add shared parser library app/testpmd: use shared flow parser library examples/flow_parsing: add flow parser demo
test: add flow parser library functional tests

 MAINTAINERS                                   |     6 +-
 app/test-pmd/cmd_flex_item.c                  |    41 +-
 app/test-pmd/cmdline.c                        |   267 +-
 app/test-pmd/config.c                         |   112 +-
 app/test-pmd/flow_parser.c                    |   409 +
 app/test-pmd/flow_parser_cli.c                |   153 +
 app/test-pmd/meson.build                      |     5 +-
 app/test-pmd/testpmd.c                        |     4 +
 app/test-pmd/testpmd.h                        |   122 +-
 app/test/meson.build                          |     1 +
 app/test/test_ethdev_api.c                    |    51 +
 app/test/test_flow_parser.c                   |   923 ++
 doc/api/doxy-api-index.md                     |     1 +
 doc/api/doxy-api.conf.in                      |     1 +
 doc/guides/prog_guide/flow_parser_lib.rst     |   110 +
 doc/guides/prog_guide/index.rst               |     1 +
 doc/guides/rel_notes/release_26_03.rst        |     9 +
 examples/flow_parsing/main.c                  |   292 +
 examples/flow_parsing/meson.build             |    11 +
 examples/meson.build                          |     1 +
 lib/cmdline/cmdline_parse.h                   |     2 +
 lib/ethdev/rte_ethdev.c                       |   107 +
 lib/ethdev/rte_ethdev.h                       |    55 +
 lib/flow_parser/meson.build                   |     7 +
 .../flow_parser/rte_flow_parser.c             | 11420 ++++++++--------
 lib/flow_parser/rte_flow_parser.h             |   134 +
 lib/flow_parser/rte_flow_parser_private.h     |  1247 ++
 lib/meson.build                               |     2 +
 28 files changed, 9671 insertions(+), 5823 deletions(-)
 create mode 100644 app/test-pmd/flow_parser.c
 create mode 100644 app/test-pmd/flow_parser_cli.c

 create mode 100644 app/test/test_flow_parser.c
 create mode 100644 doc/guides/prog_guide/flow_parser_lib.rst
 create mode 100644 examples/flow_parsing/main.c
 create mode 100644 examples/flow_parsing/meson.build
 create mode 100644 lib/flow_parser/meson.build
 rename app/test-pmd/cmdline_flow.c => lib/flow_parser/rte_flow_parser.c (55%)
 create mode 100644 lib/flow_parser/rte_flow_parser.h
 create mode 100644 lib/flow_parser/rte_flow_parser_private.h

(quoted diff) +13 -0

+int
+rte_flow_parser_run(const char *src)
+{
+	uint8_t buf[4096];
+	struct rte_flow_parser_output *out = (struct rte_flow_parser_output *)buf;
+	int ret;
+
+	ret = rte_flow_parser_parse(src,
+				    (struct rte_flow_parser_output *)buf,
+				    sizeof(buf));
+	if (ret < 0)
+		return ret;
+	switch (out->command) {

The kernel version of checkpatch complains here. The DPDK shell script seems to be set to ignore this but.

WARNING: break is not useful after a return #15008: FILE: lib/flow_parser/rte_flow_parser.c:14763:

(quoted diff) +2 -0

+               return cmd_flow_parsed(out);
+               break;

Should I create a new patch set or just let it be at this moment?

Quoted 10 lines

The kernel version of checkpatch complains here. The DPDK shell script seems to be set to ignore this but.

WARNING: break is not useful after a return #15008: FILE: lib/flow_parser/rte_flow_parser.c:14763:

(quoted diff) +2 -0

+               return cmd_flow_parsed(out);
+               break;

Should I create a new patch set or just let it be at this moment?

Lukas

Quoted 9 lines · On Tue, 3 Feb 2026 09:34:26 +0100 Lukáš Šišmiš <[email protected]> wrote:

Quoted 9 lines

The kernel version of checkpatch complains here. The DPDK shell script seems to be set to ignore this but.

WARNING: break is not useful after a return #15008: FILE: lib/flow_parser/rte_flow_parser.c:14763:

(quoted diff) +2 -0

+               return cmd_flow_parsed(out);
+               break;

Quoted 2 lines

Quoted 1 line

Should I create a new patch set or just let it be at this moment?

Lukas

I am ok with it as is.

04/02/2026 15:53, Stephen Hemminger:

Quoted 5 lines

Quoted 2 lines · On Tue, 3 Feb 2026 09:34:26 +0100 Lukáš Šišmiš <[email protected]> wrote:

Quoted 2 lines

The kernel version of checkpatch complains here. The DPDK shell

script

Quoted 7 lines

Quoted 7 lines

Quoted 7 lines

seems to be set to ignore this but.

WARNING: break is not useful after a return #15008: FILE: lib/flow_parser/rte_flow_parser.c:14763:

(quoted diff) +2 -0

+               return cmd_flow_parsed(out);
+               break;

Quoted 5 lines

Quoted 2 lines

Quoted 1 line

Should I create a new patch set or just let it be at this moment?

Lukas

I am ok with it as is.

Better to update.

There are other warnings:

WARNING:STRNCPY: Prefer strscpy, strscpy_pad, or __nonstring over strncpy
- see: https://github.com/KSPP/linux/issues/90
#13052 <https://github.com/KSPP/linux/issues/90#13052>: FILE:
lib/flow_parser/rte_flow_parser.c:12825:
+ strncpy(buf, str, len);

and a lot of WARNING:LONG_LINE

I can have a look after the decision.

And on a more general note, I would have expected to ask the opinion of rte_flow maintainers, but they are not Cc'ed in these patches.

I'm a bit skeptical about adding this outside of ethdev library which defines the flow API.

pá 6. 2. 2026 v 15:02 odesílatel Thomas Monjalon <[email protected]> napsal:

Quoted 30 lines

04/02/2026 15:53, Stephen Hemminger:

Quoted 5 lines

Quoted 2 lines · On Tue, 3 Feb 2026 09:34:26 +0100 Lukáš Šišmiš <[email protected]> wrote:

Quoted 2 lines

The kernel version of checkpatch complains here. The DPDK shell

script

Quoted 7 lines

Quoted 7 lines

Quoted 7 lines

seems to be set to ignore this but.

WARNING: break is not useful after a return #15008: FILE: lib/flow_parser/rte_flow_parser.c:14763:

(quoted diff) +2 -0

+               return cmd_flow_parsed(out);
+               break;

Quoted 5 lines

Quoted 2 lines

Quoted 1 line

Should I create a new patch set or just let it be at this moment?

Lukas

I am ok with it as is.

Better to update.

There are other warnings:

WARNING:STRNCPY: Prefer strscpy, strscpy_pad, or __nonstring over strncpy
- see: https://github.com/KSPP/linux/issues/90
#13052 <https://github.com/KSPP/linux/issues/90#13052>: FILE:
lib/flow_parser/rte_flow_parser.c:12825:
+ strncpy(buf, str, len);

Quoted 8 lines

and a lot of WARNING:LONG_LINE

I can have a look after the decision.

And on a more general note, I would have expected to ask the opinion of rte_flow maintainers, but they are not Cc'ed in these patches.

I communicated primarily with Stephen, and will CC Ori too. Anyone else?

Quoted 3 lines

I'm a bit skeptical about adding this outside of ethdev library which defines the flow API.

CCing Ori to make a decision. I don't mind putting it directly into ethdev as well, I just thought the parser could be its own separate lib as it is just consuming strings and producing rte_flow structures. I can see the heavy ties to the flow library, though. Thomas, Stephen, what are your opinions?

Quoted 18 lines · On Fri, 6 Feb 2026 16:40:39 +0100 Lukáš Šišmiš <[email protected]> wrote:

pá 6. 2. 2026 v 15:02 odesílatel Thomas Monjalon <[email protected]> napsal:

Quoted 15 lines

04/02/2026 15:53, Stephen Hemminger:

Quoted 5 lines

Quoted 2 lines · On Tue, 3 Feb 2026 09:34:26 +0100 Lukáš Šišmiš <[email protected]> wrote:

Quoted 2 lines

The kernel version of checkpatch complains here. The DPDK shell

script

Quoted 8 lines

Quoted 8 lines

Quoted 8 lines

seems to be set to ignore this but.

WARNING: break is not useful after a return #15008: FILE: lib/flow_parser/rte_flow_parser.c:14763:

(quoted diff) +2 -0

+               return cmd_flow_parsed(out);
+               break;

Should I create a new patch set or just let it be at this

moment?

Quoted 10 lines

Quoted 10 lines

Quoted 4 lines

Quoted 1 line

Lukas

I am ok with it as is.

Better to update.

There are other warnings:

WARNING:STRNCPY: Prefer strscpy, strscpy_pad, or __nonstring over

strncpy

Quoted 13 lines

Quoted 5 lines

- see: https://github.com/KSPP/linux/issues/90
#13052 <https://github.com/KSPP/linux/issues/90#13052>: FILE:
lib/flow_parser/rte_flow_parser.c:12825:
+ strncpy(buf, str, len);

Quoted 8 lines

and a lot of WARNING:LONG_LINE

I can have a look after the decision.

And on a more general note, I would have expected to ask the opinion of rte_flow maintainers, but they are not Cc'ed in these patches.

Quoted 8 lines

I communicated primarily with Stephen, and will CC Ori too. Anyone else?

Quoted 3 lines

I'm a bit skeptical about adding this outside of ethdev library which defines the flow API.

CCing Ori to make a decision. I don't mind putting it directly into

ethdev

Quoted 4 lines

as well, I just thought the parser could be its own separate lib as it is just consuming strings and producing rte_flow structures. I can see the heavy ties to the flow library, though. Thomas, Stephen, what are your opinions?

I am beginning to agree with Thomas, this belongs in the ethdev directory next to rte_flow.

Also, not sure what the purpose of parser_ops is. It says to pass NULL, but test-pmd is doing something else. It would be better to have an initializer (i.e RTE_INIT) instead? Maybe

Ok, I can move it there then. Should I proceed with Patch v11 - that would include moving the ethdev directory and addressing the kernel's checkpatch issues?

The initializer doesn't seem like a bad idea. I didn't know about that one. The parser_ops are not needed for purely parsing, but to remain compatible with the testpmd's code, which is using, e.g., the hints on the commandline I added parser_ops.
The simple public library API is for converting strings to rte_flow structures,
the parser_ops is for hooking up the testpmd.

pá 13. 2. 2026 v 1:43 odesílatel Stephen Hemminger < [email protected]> napsal:

Quoted 65 lines

Quoted 20 lines · On Fri, 6 Feb 2026 16:40:39 +0100 Lukáš Šišmiš <[email protected]> wrote:

pá 6. 2. 2026 v 15:02 odesílatel Thomas Monjalon
<[email protected]> napsal:

Quoted 17 lines

04/02/2026 15:53, Stephen Hemminger:

Quoted 6 lines

Quoted 3 lines · On Tue, 3 Feb 2026 09:34:26 +0100 Lukáš Šišmiš <[email protected]> wrote:

Quoted 3 lines

The kernel version of checkpatch complains here. The DPDK shell

script

Quoted 9 lines

Quoted 9 lines

Quoted 9 lines

seems to be set to ignore this but.

WARNING: break is not useful after a return #15008: FILE: lib/flow_parser/rte_flow_parser.c:14763:

(quoted diff) +2 -0

+               return cmd_flow_parsed(out);
+               break;

Should I create a new patch set or just let it be at this

moment?

Quoted 11 lines

Quoted 11 lines

Quoted 4 lines

Quoted 1 line

Lukas

I am ok with it as is.

Better to update.

There are other warnings:

WARNING:STRNCPY: Prefer strscpy, strscpy_pad, or __nonstring over

strncpy

Quoted 17 lines

Quoted 5 lines

- see: https://github.com/KSPP/linux/issues/90
#13052 <https://github.com/KSPP/linux/issues/90#13052>: FILE:
lib/flow_parser/rte_flow_parser.c:12825:
+ strncpy(buf, str, len);

Quoted 8 lines

and a lot of WARNING:LONG_LINE

I can have a look after the decision.

And on a more general note, I would have expected to ask the opinion of rte_flow maintainers, but they are not Cc'ed in these patches.

I communicated primarily with Stephen, and will CC Ori too. Anyone else?

Quoted 6 lines

Quoted 3 lines

I'm a bit skeptical about adding this outside of ethdev library which defines the flow API.

CCing Ori to make a decision. I don't mind putting it directly into

ethdev

Quoted 4 lines

as well, I just thought the parser could be its own separate lib as it is just consuming strings and producing rte_flow structures. I can see the heavy ties to the flow library, though. Thomas, Stephen, what are your opinions?

Quoted 7 lines

I am beginning to agree with Thomas, this belongs in the ethdev directory next to rte_flow.

Also, not sure what the purpose of parser_ops is. It says to pass NULL, but test-pmd is doing something else. It would be better to have an initializer (i.e RTE_INIT) instead? Maybe

Ok, I can move it there then. Should I proceed with Patch v11 - that would include moving the ethdev directory and addressing the kernel's checkpatch issues?

The initializer doesn't seem like a bad idea. I didn't know about that one. The parser_ops are not needed for purely parsing, but to remain compatible with the testpmd's code, which is using, e.g., the hints on the commandline I added parser_ops.
The simple public library API is for converting strings to rte_flow structures,
the parser_ops is for hooking up the testpmd.

Introduce librte_flow_parser as an experimental library exposing the testpmd flow CLI parser as an optional reusable component.

The library provides:
- rte_flow_parser_init(): Initialize parser with operation callbacks
- rte_flow_parser_parse(): Parse flow command strings into output
- rte_flow_parser_run(): Parse and execute via registered callbacks
- Lightweight functions for parsing pattern/action/attribute strings

The parser uses a single global instance design for simplicity. All parsing state is internal to the library. Callbacks are invoked for flow create, destroy, validate, query and other flow operations.

This enables applications to reuse testpmd's well-tested flow syntax without duplicating the parser implementation.

Other applications should primarily leverage the functions for separately parsing rte_flow rule attributes/patterns/actions.

Signed-off-by Lukas Sismis <[email protected]>

This series extracts the testpmd flow CLI parser into a reusable library, enabling external applications to parse rte_flow rules using testpmd syntax.

Motivation
----------
External applications like Suricata IDS [1] need to express hardware filtering rules in a consistent, human-readable format. Rather than inventing custom syntax, reusing testpmd's well-tested flow grammar provides immediate compatibility with existing documentation and user knowledge.

Note: This library provides only one way to create rte_flow structures. Applications can also construct rte_flow_attr, rte_flow_item[], and rte_flow_action[] directly in C code.

Design
------
The library (librte_flow_parser) exposes the following APIs:
- rte_flow_parser_parse_attr_str(): Parse attributes only
- rte_flow_parser_parse_pattern_str(): Parse patterns only
- rte_flow_parser_parse_actions_str(): Parse actions only

Testpmd is updated to use the library, ensuring a single maintained parser implementation.

Testing and Demo
-------
- Functional tests in dpdk-test
- Example application: examples/flow_parsing

Quoted 2 lines · On Mon, 2 Feb 2026 12:36:52 +0100 Lukas Sismis <[email protected]> wrote:

This series extracts the testpmd flow CLI parser into a reusable library, enabling external applications to parse rte_flow rules using testpmd

syntax.

Quoted 4 lines

Motivation
----------
External applications like Suricata IDS [1] need to express hardware

filtering

Quoted 1 line

rules in a consistent, human-readable format. Rather than inventing

custom

Quoted 17 lines

syntax, reusing testpmd's well-tested flow grammar provides immediate compatibility with existing documentation and user knowledge.

Note: This library provides only one way to create rte_flow structures. Applications can also construct rte_flow_attr, rte_flow_item[], and rte_flow_action[] directly in C code.

Design
------
The library (librte_flow_parser) exposes the following APIs:
- rte_flow_parser_parse_attr_str(): Parse attributes only
- rte_flow_parser_parse_pattern_str(): Parse patterns only
- rte_flow_parser_parse_actions_str(): Parse actions only

Testpmd is updated to use the library, ensuring a single maintained parser implementation.

Quoted 4 lines

Testing and Demo
-------
- Functional tests in dpdk-test
- Example application: examples/flow_parsing

I am working on being able to use null PMD to exercise rte_flow. Will add another automated test to exercise flow parser in automated test.