[v2,2/2] examples/flow_classify: add an ACL table for tcp

  v2 updates: typo fixes for checkpatch,  bernard.iremonger comments

The struct rte_flow_classifier can have up to RTE_FLOW_CLASSIFY_TABLE_MAX
(32) classifier tables, but the existing flow_classify examples only adds
a single table for the L4 5-tuple.

When dealing with tcp flows, we frequently want to add ACLs and filters
to filter based on the state of the TCP connection, e.g., by looking at
the tcp flags field.

So we enhance flow_classify to add an additional acl table for
tcp 5-tuples. If the input-file-parser detects a filter for a tcp flow with
a non-wildcard argument for tcp_flags, the IP4_TCP_5TUPLE table is used
by flow_classify.

Signed-off-by: Sowmini Varadhan <sovaradh@linux.microsoft.com>
---
 examples/flow_classify/flow_classify.c      | 41 +++++++---
 lib/flow_classify/rte_flow_classify.c       | 87 +++++++++++++++++++++
 lib/flow_classify/rte_flow_classify.h       | 19 +++++
 lib/flow_classify/rte_flow_classify_parse.c |  8 +-
 4 files changed, 142 insertions(+), 13 deletions(-)
  

Hi Sowmini,

> -----Original Message-----
> From: Sowmini Varadhan <sovaradh@linux.microsoft.com>
> Sent: Wednesday, August 18, 2021 4:01 PM
> To: sowmini05@gmail.com; Iremonger, Bernard
> <bernard.iremonger@intel.com>; dev@dpdk.org;
> sovaradh@linux.microsoft.com
> Cc: thomas@monjalon.net
> Subject: [PATCH v2 2/2] examples/flow_classify: add an ACL table for tcp
> 
> v2 updates: typo fixes for checkpatch,  bernard.iremonger comments

The above line should not be added to the commit message.
~/dpdk/devtools/check-git-log.sh -1
Wrong tag:
        v2 fixes:  typo fixes, get_tcp_flags returns -EINVAL

The check-git-log.sh  script is in your dpdk checkout, best to run this script before sending patches

> 
> The struct rte_flow_classifier can have up to
> RTE_FLOW_CLASSIFY_TABLE_MAX
> (32) classifier tables, but the existing flow_classify examples only adds a
> single table for the L4 5-tuple.
> 
> When dealing with tcp flows, we frequently want to add ACLs and filters to
> filter based on the state of the TCP connection, e.g., by looking at the tcp
> flags field.
> 
> So we enhance flow_classify to add an additional acl table for tcp 5-tuples. If
> the input-file-parser detects a filter for a tcp flow with a non-wildcard
> argument for tcp_flags, the IP4_TCP_5TUPLE table is used by flow_classify.
> 
> Signed-off-by: Sowmini Varadhan <sovaradh@linux.microsoft.com>
> ---

If you want comment on the patch updates (optional), it can be added here after the --- line

>  examples/flow_classify/flow_classify.c      | 41 +++++++---
>  lib/flow_classify/rte_flow_classify.c       | 87 +++++++++++++++++++++
>  lib/flow_classify/rte_flow_classify.h       | 19 +++++
>  lib/flow_classify/rte_flow_classify_parse.c |  8 +-
>  4 files changed, 142 insertions(+), 13 deletions(-)

This patch contains changes to the flow_classify example and the flow_classify  library.
It needs to be split in two, a patch for the flow_classify example and a patch for the flow classify library.

> 
> diff --git a/examples/flow_classify/flow_classify.c
> b/examples/flow_classify/flow_classify.c
> index ff4c8bc2f5..8f6aacae03 100644
> --- a/examples/flow_classify/flow_classify.c
> +++ b/examples/flow_classify/flow_classify.c
> @@ -723,11 +723,6 @@ add_classify_rule(struct rte_eth_ntuple_filter
> *ntuple_filter,
>  		return ret;
>  	}
> 
> -	/* XXX but this only adds table_type of
> -	 * RTE_FLOW_CLASSIFY_TABLE_ACL_IP4_5TUPLE
> -	 * i.e., it only ever does allocate_acl_ipv4_5tuple_rule()
> -	 * so the tcp_flags is ignored!
> -	 */
>  	rule = rte_flow_classify_table_entry_add(
>  			cls_app->cls, &attr, pattern_ipv4_5tuple,
>  			actions, &key_found, &error);
> @@ -856,7 +851,8 @@ main(int argc, char *argv[])
>  	int ret;
>  	int socket_id;
>  	struct rte_table_acl_params table_acl_params;
> -	struct rte_flow_classify_table_params cls_table_params;
> +	struct rte_table_acl_params table_acl_tcp_params;
> +	struct rte_flow_classify_table_params cls_table_params[2];
>  	struct flow_classifier *cls_app;
>  	struct rte_flow_classifier_params cls_params;
>  	uint32_t size;
> @@ -923,21 +919,42 @@ main(int argc, char *argv[])
>  	memcpy(table_acl_params.field_format, ipv4_defs,
> sizeof(ipv4_defs));
> 
>  	/* initialise table create params */
> -	cls_table_params.ops = &rte_table_acl_ops;
> -	cls_table_params.arg_create = &table_acl_params;
> -	cls_table_params.type =
> RTE_FLOW_CLASSIFY_TABLE_ACL_IP4_5TUPLE;
> +	cls_table_params[0].ops = &rte_table_acl_ops;
> +	cls_table_params[0].arg_create = &table_acl_params;
> +	cls_table_params[0].type =
> RTE_FLOW_CLASSIFY_TABLE_ACL_IP4_5TUPLE;
> +
> +	/* initialise ACL table params */
> +	table_acl_tcp_params.name = "table_acl_ipv4_tcp_5tuple";
> +	table_acl_tcp_params.n_rules = FLOW_CLASSIFY_MAX_RULE_NUM;
> +	table_acl_tcp_params.n_rule_fields = RTE_DIM(ipv4_defs);
> +	memcpy(table_acl_tcp_params.field_format, ipv4_defs,
> +sizeof(ipv4_defs));
> +
> +	/* initialise table create params */
> +	cls_table_params[1].ops = &rte_table_acl_ops;
> +	cls_table_params[1].arg_create = &table_acl_tcp_params;
> +	cls_table_params[1].type =
> RTE_FLOW_CLASSIFY_TABLE_ACL_IP4_TCP_5TUPLE;
> 
> -	ret = rte_flow_classify_table_create(cls_app->cls,
> &cls_table_params);
> +	ret = rte_flow_classify_table_create(cls_app->cls,
> +					     &cls_table_params[0]);
>  	if (ret) {
>  		rte_flow_classifier_free(cls_app->cls);
>  		rte_free(cls_app);
>  		rte_exit(EXIT_FAILURE, "Failed to create classifier table\n");
>  	}
> +	ret = rte_flow_classify_table_create(cls_app->cls,
> +					     &cls_table_params[1]);
> +	if (ret) {
> +		rte_flow_classifier_free(cls_app->cls);
> +		rte_free(cls_app);
> +		rte_exit(EXIT_FAILURE,
> +			 "Failed to create classifier table\n");
> +	}
> +
>  	/* >8 End of initialization of table create params. */
> 
>  	/* read file of IPv4 5 tuple rules and initialize parameters
> -	 * for rte_flow_classify_validate and
> rte_flow_classify_table_entry_add
> -	 * API's.
> +	 * for rte_flow_classify_validate and
> +	 * rte_flow_classify_table_entry_add  API's.
>  	 */
> 
>  	/* Read file of IPv4 tuple rules. 8< */ diff --git
> a/lib/flow_classify/rte_flow_classify.c b/lib/flow_classify/rte_flow_classify.c
> index d3ba2ed227..e960c3b140 100644
> --- a/lib/flow_classify/rte_flow_classify.c
> +++ b/lib/flow_classify/rte_flow_classify.c
> @@ -60,6 +60,7 @@ enum {
>  	DST_FIELD_IPV4,
>  	SRCP_FIELD_IPV4,
>  	DSTP_FIELD_IPV4,
> +	TCP_FLAGS_FIELD,

I think it would be better to rename TCP_FLAGS_FIELD to FLAGS_FIELD_TCP in line with the other values.

>  	NUM_FIELDS_IPV4
>  };
> 
> @@ -72,6 +73,7 @@ struct classify_rules {
>  	enum rte_flow_classify_rule_type type;
>  	union {
>  		struct rte_flow_classify_ipv4_5tuple ipv4_5tuple;
> +		struct rte_flow_classify_ipv4_tcp_5tuple ipv4_tcp_5tuple;
>  	} u;
>  };
> 
> @@ -477,6 +479,84 @@ allocate_acl_ipv4_5tuple_rule(struct
> rte_flow_classifier *cls)
>  	return rule;
>  }
> 
> +static struct rte_flow_classify_rule *
> +allocate_acl_ipv4_tcp_5tuple_rule(struct rte_flow_classifier *cls) {
> +	struct rte_flow_classify_rule *rule;
> +	int log_level;
> +
> +	rule = malloc(sizeof(struct rte_flow_classify_rule));
> +	if (!rule)
> +		return rule;
> +
> +	memset(rule, 0, sizeof(struct rte_flow_classify_rule));
> +	rule->id = unique_id++;
> +	rule->rules.type =
> RTE_FLOW_CLASSIFY_RULE_TYPE_IPV4_TCP_5TUPLE;
> +
> +	/* key add values */
> +	rule->u.key.key_add.priority = cls->ntuple_filter.priority;
> +	rule-
> >u.key.key_add.field_value[PROTO_FIELD_IPV4].mask_range.u8 =
> +			cls->ntuple_filter.proto_mask;
> +	rule->u.key.key_add.field_value[PROTO_FIELD_IPV4].value.u8 =
> +			cls->ntuple_filter.proto;
> +	rule->rules.u.ipv4_tcp_5tuple.proto = cls->ntuple_filter.proto;
> +	rule->rules.u.ipv4_tcp_5tuple.proto_mask =
> +			cls->ntuple_filter.proto_mask;
> +
> +	rule->u.key.key_add.field_value[SRC_FIELD_IPV4].mask_range.u32
> =
> +			cls->ntuple_filter.src_ip_mask;
> +	rule->u.key.key_add.field_value[SRC_FIELD_IPV4].value.u32 =
> +			cls->ntuple_filter.src_ip;
> +	rule->rules.u.ipv4_tcp_5tuple.src_ip_mask =
> +			cls->ntuple_filter.src_ip_mask;
> +	rule->rules.u.ipv4_tcp_5tuple.src_ip = cls->ntuple_filter.src_ip;
> +
> +	rule->u.key.key_add.field_value[DST_FIELD_IPV4].mask_range.u32
> =
> +			cls->ntuple_filter.dst_ip_mask;
> +	rule->u.key.key_add.field_value[DST_FIELD_IPV4].value.u32 =
> +			cls->ntuple_filter.dst_ip;
> +	rule->rules.u.ipv4_tcp_5tuple.dst_ip_mask =
> +			cls->ntuple_filter.dst_ip_mask;
> +	rule->rules.u.ipv4_tcp_5tuple.dst_ip = cls->ntuple_filter.dst_ip;
> +
> +	rule-
> >u.key.key_add.field_value[SRCP_FIELD_IPV4].mask_range.u16 =
> +			cls->ntuple_filter.src_port_mask;
> +	rule->u.key.key_add.field_value[SRCP_FIELD_IPV4].value.u16 =
> +			cls->ntuple_filter.src_port;
> +	rule->rules.u.ipv4_tcp_5tuple.src_port_mask =
> +			cls->ntuple_filter.src_port_mask;
> +	rule->rules.u.ipv4_tcp_5tuple.src_port = cls->ntuple_filter.src_port;
> +
> +	rule-
> >u.key.key_add.field_value[DSTP_FIELD_IPV4].mask_range.u16 =
> +			cls->ntuple_filter.dst_port_mask;
> +	rule->u.key.key_add.field_value[DSTP_FIELD_IPV4].value.u16 =
> +			cls->ntuple_filter.dst_port;
> +	rule->rules.u.ipv4_tcp_5tuple.dst_port_mask =
> +			cls->ntuple_filter.dst_port_mask;
> +	rule->rules.u.ipv4_tcp_5tuple.dst_port = cls->ntuple_filter.dst_port;
> +
> +	rule-
> >u.key.key_add.field_value[TCP_FLAGS_FIELD].mask_range.u32 =
> +			rte_be_to_cpu_32(0xff);
> +	rule->u.key.key_add.field_value[TCP_FLAGS_FIELD].value.u32 =
> +			rte_be_to_cpu_32(cls->ntuple_filter.tcp_flags);
> +	rule->rules.u.ipv4_tcp_5tuple.tcp_flags =
> +cls->ntuple_filter.tcp_flags;
> +
> +	log_level = rte_log_get_level(librte_flow_classify_logtype);
> +
> +	if (log_level == RTE_LOG_DEBUG)
> +		print_acl_ipv4_key_add(&rule->u.key.key_add);
> +
> +	/* key delete values */
> +	memcpy(&rule->u.key.key_del.field_value[PROTO_FIELD_IPV4],
> +	       &rule->u.key.key_add.field_value[PROTO_FIELD_IPV4],
> +	       NUM_FIELDS_IPV4 * sizeof(struct rte_acl_field));
> +
> +	if (log_level == RTE_LOG_DEBUG)
> +		print_acl_ipv4_key_delete(&rule->u.key.key_del);
> +
> +	return rule;
> +}
> +
>  struct rte_flow_classify_rule *
>  rte_flow_classify_table_entry_add(struct rte_flow_classifier *cls,
>  		const struct rte_flow_attr *attr,
> @@ -514,6 +594,13 @@ rte_flow_classify_table_entry_add(struct
> rte_flow_classifier *cls,
>  		rule->tbl_type = table_type;
>  		cls->table_mask |= table_type;
>  		break;
> +	case RTE_FLOW_CLASSIFY_TABLE_ACL_IP4_TCP_5TUPLE:
> +		rule = allocate_acl_ipv4_tcp_5tuple_rule(cls);
> +		if (!rule)
> +			return NULL;
> +		rule->tbl_type = table_type;
> +		cls->table_mask |= table_type;
> +		break;
>  	default:
>  		return NULL;
>  	}
> diff --git a/lib/flow_classify/rte_flow_classify.h
> b/lib/flow_classify/rte_flow_classify.h
> index 82ea92b6a6..65585d9f92 100644
> --- a/lib/flow_classify/rte_flow_classify.h
> +++ b/lib/flow_classify/rte_flow_classify.h
> @@ -80,6 +80,8 @@ enum rte_flow_classify_rule_type {
>  	RTE_FLOW_CLASSIFY_RULE_TYPE_NONE,
>  	/** IPv4 5tuple type */
>  	RTE_FLOW_CLASSIFY_RULE_TYPE_IPV4_5TUPLE,
> +	/** IPv4 TCP 5tuple type */
> +	RTE_FLOW_CLASSIFY_RULE_TYPE_IPV4_TCP_5TUPLE,
>  };
> 
>  /** Flow classify table type */
> @@ -92,6 +94,8 @@ enum rte_flow_classify_table_type {
>  	RTE_FLOW_CLASSIFY_TABLE_ACL_VLAN_IP4_5TUPLE = 1 << 2,
>  	/** ACL QinQ IP4 5TUPLE */
>  	RTE_FLOW_CLASSIFY_TABLE_ACL_QINQ_IP4_5TUPLE = 1 << 3,
> +	/** ACL IP4 5TUPLE with tcp_flags */
> +	RTE_FLOW_CLASSIFY_TABLE_ACL_IP4_TCP_5TUPLE = 1 << 4,
> 
>  };
> 
> @@ -131,6 +135,21 @@ struct rte_flow_classify_ipv4_5tuple {
>  	uint8_t proto_mask;      /**< Mask of L4 protocol. */
>  };
> 
> +/** IPv4 5-tuple data with tcp flags*/
> +struct rte_flow_classify_ipv4_tcp_5tuple {
> +	uint32_t dst_ip;         /**< Destination IP address in big endian. */
> +	uint32_t dst_ip_mask;    /**< Mask of destination IP address. */
> +	uint32_t src_ip;         /**< Source IP address in big endian. */
> +	uint32_t src_ip_mask;    /**< Mask of destination IP address. */
> +	uint16_t dst_port;       /**< Destination port in big endian. */
> +	uint16_t dst_port_mask;  /**< Mask of destination port. */
> +	uint16_t src_port;       /**< Source Port in big endian. */
> +	uint16_t src_port_mask;  /**< Mask of source port. */
> +	uint8_t proto;           /**< L4 protocol. */
> +	uint8_t proto_mask;      /**< Mask of L4 protocol. */
> +	uint8_t tcp_flags;       /**< Tcp only */
> +};
> +
>  /**
>   * Flow stats
>   *
> diff --git a/lib/flow_classify/rte_flow_classify_parse.c
> b/lib/flow_classify/rte_flow_classify_parse.c
> index 465330291f..fe4ee05b6f 100644
> --- a/lib/flow_classify/rte_flow_classify_parse.c
> +++ b/lib/flow_classify/rte_flow_classify_parse.c
> @@ -216,6 +216,7 @@ classify_parse_ntuple_filter(const struct
> rte_flow_attr *attr,
>  	const struct rte_flow_action_count *count;
>  	const struct rte_flow_action_mark *mark_spec;
>  	uint32_t index;
> +	bool have_tcp = false;
> 
>  	/* parse pattern */
>  	index = 0;
> @@ -375,6 +376,8 @@ classify_parse_ntuple_filter(const struct
> rte_flow_attr *attr,
>  		filter->dst_port  = tcp_spec->hdr.dst_port;
>  		filter->src_port  = tcp_spec->hdr.src_port;
>  		filter->tcp_flags = tcp_spec->hdr.tcp_flags;
> +		if (filter->tcp_flags != 0)
> +			have_tcp = true;
>  	} else if (item->type == RTE_FLOW_ITEM_TYPE_UDP) {
>  		udp_mask = item->mask;
> 
> @@ -434,7 +437,10 @@ classify_parse_ntuple_filter(const struct
> rte_flow_attr *attr,
>  		return -EINVAL;
>  	}
> 
> -	table_type = RTE_FLOW_CLASSIFY_TABLE_ACL_IP4_5TUPLE;
> +	if (have_tcp)
> +		table_type =
> RTE_FLOW_CLASSIFY_TABLE_ACL_IP4_TCP_5TUPLE;
> +	else
> +		table_type = RTE_FLOW_CLASSIFY_TABLE_ACL_IP4_5TUPLE;
> 
>  	/* parse attr */
>  	/* must be input direction */
> --
> 2.17.1

Regards,

Bernard.
  

On (08/19/21 15:06), Iremonger, Bernard wrote:
> > v2 updates: typo fixes for checkpatch,  bernard.iremonger comments
> 
> The above line should not be added to the commit message.
> ~/dpdk/devtools/check-git-log.sh -1
> Wrong tag:
>         v2 fixes:  typo fixes, get_tcp_flags returns -EINVAL
> 
> The check-git-log.sh  script is in your dpdk checkout, best to run this script before sending patches

apologies, I was not aware of this, I will fix and send out v3. 
I did run check-git-log.sh but before editing the vX updates.

thanks for your patience.

--Sowmini
  

Hi Sowmini,

Looking closer at this patchset, I am not sure that a second ACL table is needed.
The existing ACL table handles UDP, TCP and SCP, however it is not processing the TCP flags.
I think it just needs to be modified to process the TCP flags.
Could you take another look to see if the above proposed solution will work for you.

Regards,

Bernard. 

> -----Original Message-----
> From: Sowmini Varadhan <sovaradh@linux.microsoft.com>
> Sent: Thursday, August 19, 2021 4:21 PM
> To: Iremonger, Bernard <bernard.iremonger@intel.com>
> Cc: sowmini05@gmail.com; dev@dpdk.org; thomas@monjalon.net
> Subject: Re: [PATCH v2 2/2] examples/flow_classify: add an ACL table for tcp
> 
> On (08/19/21 15:06), Iremonger, Bernard wrote:
> > > v2 updates: typo fixes for checkpatch,  bernard.iremonger comments
> >
> > The above line should not be added to the commit message.
> > ~/dpdk/devtools/check-git-log.sh -1
> > Wrong tag:
> >         v2 fixes:  typo fixes, get_tcp_flags returns -EINVAL
> >
> > The check-git-log.sh  script is in your dpdk checkout, best to run this script
> before sending patches
> 
> apologies, I was not aware of this, I will fix and send out v3.
> I did run check-git-log.sh but before editing the vX updates.
> 
> thanks for your patience.
> 
> --Sowmini
  

On (08/19/21 16:21), Iremonger, Bernard wrote:
> 
> Looking closer at this patchset, I am not sure that a second ACL table is needed.
> The existing ACL table handles UDP, TCP and SCP, however it is not processing the TCP flags.
> I think it just needs to be modified to process the TCP flags.
> Could you take another look to see if the above proposed solution will work for you.

I'm not sure it would. As I pointed out in the original rfc  at
https://inbox.dpdk.org/dev/cover.1578936382.git.sowmini.varadhan@microsoft.com/

we need to add a key for the 8 bit flags, but the multibit
trie lookup moves in steps of 4 bytes.

However, it has admittedly been a while since I tinkereed with this,
and I can give it a shot and get back.

Thanks
--Sowmini
  

On Thu, 19 Aug 2021 12:34:46 -0700
Sowmini Varadhan <sovaradh@linux.microsoft.com> wrote:

> On (08/19/21 16:21), Iremonger, Bernard wrote:
> > 
> > Looking closer at this patchset, I am not sure that a second ACL table is needed.
> > The existing ACL table handles UDP, TCP and SCP, however it is not processing the TCP flags.
> > I think it just needs to be modified to process the TCP flags.
> > Could you take another look to see if the above proposed solution will work for you.  
> 
> I'm not sure it would. As I pointed out in the original rfc  at
> https://inbox.dpdk.org/dev/cover.1578936382.git.sowmini.varadhan@microsoft.com/
> 
> we need to add a key for the 8 bit flags, but the multibit
> trie lookup moves in steps of 4 bytes.
> 
> However, it has admittedly been a while since I tinkereed with this,
> and I can give it a shot and get back.
> 
> Thanks
> --Sowmini
> 

Doing a cleanup of patch backlog prior to next LTS release.
The patch never got updated based on comments.
Please resubmit if you still want to pursue it.