[RFC 1/9] ethdev: add IPv6 routing extension header definition

[Ori Kam]

Hi Rongwei,


> -----Original Message-----
> From: Rongwei Liu <rongweil at nvidia.com>
> Sent: Wednesday, 21 December 2022 10:43
> 
> Add IPv6 routing extension header definition and no
> TLV support for now.
> At rte_flow layer, there are new items defined for matching
> type/nexthdr/segment_left field.
> 
> Signed-off-by: Rongwei Liu <rongweil at nvidia.com>
> ---
>  doc/guides/prog_guide/rte_flow.rst     |  9 ++++++
>  doc/guides/rel_notes/release_22_03.rst |  5 ++++
>  lib/ethdev/rte_flow.c                  | 15 ++++++++++
>  lib/ethdev/rte_flow.h                  | 39 ++++++++++++++++++++++++++
>  lib/net/rte_ip.h                       | 21 ++++++++++++++
>  5 files changed, 89 insertions(+)
> 
> diff --git a/doc/guides/prog_guide/rte_flow.rst
> b/doc/guides/prog_guide/rte_flow.rst
> index 3e6242803d..1ebc159893 100644
> --- a/doc/guides/prog_guide/rte_flow.rst
> +++ b/doc/guides/prog_guide/rte_flow.rst
> @@ -1544,6 +1544,15 @@ Matches Color Marker set by a Meter.
> 
>  - ``color``: Metering color marker.
> 
> +Item: ``IPV6_ROUTING_EXT``
> +^^^^^^^^^^^^^^^^^^^^^
> +
> +Matches ipv6 routing extension header.
> +
> +- ``nexthdr``: Next layer header type.
> +- ``type``: IPv6 routing extension header type.
> +- ``segments_left``: How many IPv6 destination addresses carries on
> +
>  Actions
>  ~~~~~~~
> 
> diff --git a/doc/guides/rel_notes/release_22_03.rst
> b/doc/guides/rel_notes/release_22_03.rst
> index 0923707cb8..cc050ff3e7 100644
> --- a/doc/guides/rel_notes/release_22_03.rst
> +++ b/doc/guides/rel_notes/release_22_03.rst
> @@ -207,6 +207,11 @@ API Changes
>  * ethdev: Old public macros and enumeration constants without
> ``RTE_ETH_`` prefix,
>    which are kept for backward compatibility, are marked as deprecated.
> 
> +* ethdev: added a new structure:
> +
> +    - IPv6 routing extension header ``rte_flow_item_ipv6_routing_ext`` and
> +      ``rte_ipv6_routing_ext``
> +
>  * cryptodev: The asymmetric session handling was modified to use a single
>    mempool object. An API ``rte_cryptodev_asym_session_pool_create`` was
> added
>    to create a mempool with element size big enough to hold the generic
> asymmetric
> diff --git a/lib/ethdev/rte_flow.c b/lib/ethdev/rte_flow.c
> index 7d0c24366c..e08b690300 100644
> --- a/lib/ethdev/rte_flow.c
> +++ b/lib/ethdev/rte_flow.c
> @@ -76,6 +76,19 @@ rte_flow_item_flex_conv(void *buf, const void *data)
>  	return src->length;
>  }
> 
> +static size_t
> +rte_flow_item_ipv6_routing_ext_conv(void *buf, const void *data)
> +{
> +	struct rte_flow_item_ipv6_routing_ext *dst = buf;
> +	const struct rte_flow_item_ipv6_routing_ext *src = data;
> +
> +	if (buf)
> +		rte_memcpy((void *)((uintptr_t)(dst->hdr.segments)),
> +			   src->hdr.segments,
> +			   src->hdr.segments_left << 4);
> +	return src->hdr.segments_left << 4;
> +}
> +
>  /** Generate flow_item[] entry. */
>  #define MK_FLOW_ITEM(t, s) \
>  	[RTE_FLOW_ITEM_TYPE_ ## t] = { \
> @@ -157,6 +170,8 @@ static const struct rte_flow_desc_data
> rte_flow_desc_item[] = {
>  	MK_FLOW_ITEM(L2TPV2, sizeof(struct rte_flow_item_l2tpv2)),
>  	MK_FLOW_ITEM(PPP, sizeof(struct rte_flow_item_ppp)),
>  	MK_FLOW_ITEM(METER_COLOR, sizeof(struct
> rte_flow_item_meter_color)),
> +	MK_FLOW_ITEM_FN(IPV6_ROUTING_EXT, sizeof(struct
> rte_flow_item_ipv6_routing_ext),
> +			rte_flow_item_ipv6_routing_ext_conv),
>  };
> 
>  /** Generate flow_action[] entry. */
> diff --git a/lib/ethdev/rte_flow.h b/lib/ethdev/rte_flow.h
> index b60987db4b..f8f1d6f9dd 100644
> --- a/lib/ethdev/rte_flow.h
> +++ b/lib/ethdev/rte_flow.h
> @@ -624,6 +624,33 @@ enum rte_flow_item_type {
>  	 * See struct rte_flow_item_meter_color.
>  	 */
>  	RTE_FLOW_ITEM_TYPE_METER_COLOR,
> +	/**
> +	 * Matches the presence of IPv6 routing extension header.
> +	 *
> +	 * See struct rte_flow_item_ipv6_routing_ext.
> +	 */
> +	RTE_FLOW_ITEM_TYPE_IPV6_ROUTING_EXT,
> +
> +	/**
> +	 * Matches IPv6 routing extension header next header.
> +	 *
> +	 * See struct rte_flow_item_ipv6_routing_ext.
> +	 */
> +	RTE_FLOW_ITEM_TYPE_IPV6_ROUTING_EXT_NEXT_HDR,

Why do we need this item? Isn't it part of the rte_ipv6_routing_ext?

> +
> +	/**
> +	 * Matches IPv6 routing extension header type.
> +	 *
> +	 * See struct rte_flow_item_ipv6_routing_ext.
> +	 */
> +	RTE_FLOW_ITEM_TYPE_IPV6_ROUTING_EXT_TYPE,
> +

Why do we need this item? Isn't it part of the rte_ipv6_routing_ext?

> +	/**
> +	 * Matches IPv6 routing extension header segment left.
> +	 *
> +	 * See struct rte_flow_item_ipv6_routing_ext.
> +	 */
> +	RTE_FLOW_ITEM_TYPE_IPV6_ROUTING_EXT_SEG_LEFT,

Why do we need this item? Isn't it part of the rte_ipv6_routing_ext?

>  };
> 
>  /**
> @@ -873,6 +900,18 @@ struct rte_flow_item_ipv6 {
>  	uint32_t reserved:23;
>  };
> 
> +/**
> + * @warning
> + * @b EXPERIMENTAL: this structure may change without prior notice
> + *
> + * RTE_FLOW_ITEM_TYPE_IPV6_ROUTING_EXT.
> + *
> + * Matches an IPv6 routing extension header.
> + */
> +struct rte_flow_item_ipv6_routing_ext {
> +	struct rte_ipv6_routing_ext hdr;
> +};
> +
>  /** Default mask for RTE_FLOW_ITEM_TYPE_IPV6. */
>  #ifndef __cplusplus
>  static const struct rte_flow_item_ipv6 rte_flow_item_ipv6_mask = {
> diff --git a/lib/net/rte_ip.h b/lib/net/rte_ip.h
> index 9c8e8206f0..2b9a65dfcb 100644
> --- a/lib/net/rte_ip.h
> +++ b/lib/net/rte_ip.h
> @@ -539,6 +539,27 @@ struct rte_ipv6_hdr {
>  	uint8_t  dst_addr[16];	/**< IP address of destination host(s). */
>  } __rte_packed;
> 
> +/**
> + * IPv6 Routing Extension Header
> + */
> +struct rte_ipv6_routing_ext {
> +	uint8_t nexthdr;			/**< Protocol, next header.
> */
> +	uint8_t hdrlen;				/**< Header length. */
> +	uint8_t type;				/**< Extension header type.
> */
> +	uint8_t segments_left;			/**< Valid segments number.
> */
> +	__extension__
> +	union {
> +		uint32_t flags;
> +		struct {
> +			uint8_t last_entry;	/**< The last_entry field of
> SRH */
> +			uint8_t flag;		/**< Packet flag. */
> +			uint16_t tag;		/**< Packet tag. */
> +		};
> +	};
> +	__extension__
> +	uint32_t segments[0];			/**< Each hop IPv6 address.
> */
> +} __rte_packed;
> +
>  /* IPv6 vtc_flow: IPv / TC / flow_label */
>  #define RTE_IPV6_HDR_FL_SHIFT 0
>  #define RTE_IPV6_HDR_TC_SHIFT 20
> --
> 2.27.0

Best,
Ori