Hi Bing, One more thought, PSB
Best, Ori > -----Original Message----- > From: Bing Zhao <bi...@nvidia.com> > Sent: Thursday, April 15, 2021 7:41 PM > To: Ori Kam <or...@nvidia.com>; NBU-Contact-Thomas Monjalon > <tho...@monjalon.net>; ferruh.yi...@intel.com; > andrew.rybche...@oktetlabs.ru > Cc: dev@dpdk.org; ajit.khapa...@broadcom.com > Subject: [PATCH v2 1/2] ethdev: introduce conntrack flow action and item > > This commit introduced the conntrack action and item. > > Usually the HW offloading is stateless. For some stateful offloading > like a TCP connection, HW module will help provide the ability of a > full offloading w/o SW participation after the connection was > established. > > The basic usage is that in the first flow the application should add > the conntrack action and in the following flow(s) the application > should use the conntrack item to match on the result. > > A TCP connection has two directions traffic. To set a conntrack > action context correctly, information from packets of both directions > are required. > > The conntrack action should be created on one port and supply the > peer port as a parameter to the action. After context creating, it > could only be used between the ports (dual-port mode) or a single > port. The application should modify the action via the API > "action_handle_update" only when before using it to create a flow > with opposite direction. This will help the driver to recognize the > direction of the flow to be created, especially in single port mode. > The traffic from both directions will go through the same port if > the application works as an "forwarding engine" but not a end point. > There is no need to call the update interface if the subsequent flows > have nothing to be changed. > > Query will be supported via action_ctx_query interface, about the > current packets information and connection status. Tha fields > query capabilities depends on the HW. > > For the packets received during the conntrack setup, it is suggested > to re-inject the packets in order to take full advantage of the > conntrack. Only the valid packets should pass the conntrack, packets > with invalid TCP information, like out of window, or with invalid > header, like malformed, should not pass. > > Naming and definition: > https://elixir.bootlin.com/linux/latest/source/include/uapi/linux/netfilter/nf_co > nntrack_tcp.h > https://elixir.bootlin.com/linux/latest/source/net/netfilter/nf_conntrack_proto_ > tcp.c > > Other reference: > https://www.usenix.org/legacy/events/sec01/invitedtalks/rooij.pdf > > Signed-off-by: Bing Zhao <bi...@nvidia.com> > --- > lib/librte_ethdev/rte_flow.c | 2 + > lib/librte_ethdev/rte_flow.h | 195 +++++++++++++++++++++++++++++++++++ > 2 files changed, 197 insertions(+) > > diff --git a/lib/librte_ethdev/rte_flow.c b/lib/librte_ethdev/rte_flow.c > index 27a161559d..0af601d508 100644 > --- a/lib/librte_ethdev/rte_flow.c > +++ b/lib/librte_ethdev/rte_flow.c > @@ -98,6 +98,7 @@ static const struct rte_flow_desc_data > rte_flow_desc_item[] = { > MK_FLOW_ITEM(PFCP, sizeof(struct rte_flow_item_pfcp)), > MK_FLOW_ITEM(ECPRI, sizeof(struct rte_flow_item_ecpri)), > MK_FLOW_ITEM(GENEVE_OPT, sizeof(struct > rte_flow_item_geneve_opt)), > + MK_FLOW_ITEM(CONNTRACK, sizeof(uint32_t)), > }; > > /** Generate flow_action[] entry. */ > @@ -186,6 +187,7 @@ static const struct rte_flow_desc_data > rte_flow_desc_action[] = { > * indirect action handle. > */ > MK_FLOW_ACTION(INDIRECT, 0), > + MK_FLOW_ACTION(CONNTRACK, sizeof(struct > rte_flow_action_conntrack)), > }; > > int > diff --git a/lib/librte_ethdev/rte_flow.h b/lib/librte_ethdev/rte_flow.h > index 91ae25b1da..024d1a2026 100644 > --- a/lib/librte_ethdev/rte_flow.h > +++ b/lib/librte_ethdev/rte_flow.h > @@ -551,6 +551,15 @@ enum rte_flow_item_type { > * See struct rte_flow_item_geneve_opt > */ > RTE_FLOW_ITEM_TYPE_GENEVE_OPT, > + > + /** > + * [META] > + * > + * Matches conntrack state. > + * > + * See struct rte_flow_item_conntrack. > + */ > + RTE_FLOW_ITEM_TYPE_CONNTRACK, > }; > > /** > @@ -1685,6 +1694,51 @@ rte_flow_item_geneve_opt_mask = { > }; > #endif > > +/** > + * The packet is with valid state after conntrack checking. > + */ > +#define RTE_FLOW_CONNTRACK_FLAG_PKT_STATE_VALID (1 << 0) > +/** > + * The state of the connection was changed. > + */ > +#define RTE_FLOW_CONNTRACK_FLAG_PKT_STATE_CHANGED (1 << 1) > +/** > + * Error is detected on this packet for this connection and > + * an invalid state is set. > + */ > +#define RTE_FLOW_CONNTRACK_FLAG_PKT_STATE_INVAL (1 << 2) > +/** > + * The HW connection tracking module is disabled. > + * It can be due to application command or an invalid state. > + */ > +#define RTE_FLOW_CONNTRACK_FLAG_HW_DISABLED (1 << 3) > +/** > + * The packet contains some bad field(s) and cannot continue > + * with the conntrack module checking. > + */ > +#define RTE_FLOW_CONNTRACK_FLAG_PKT_BAD (1 << 4) > + > +/** > + * @warning > + * @b EXPERIMENTAL: this structure may change without prior notice > + * > + * RTE_FLOW_ITEM_TYPE_CONNTRACK > + * > + * Matches the state of a packet after it passed the connection tracking > + * examination. The state is a bit mask of one RTE_FLOW_CONNTRACK_FLAG* > + * or a reasonable combination of these bits. > + */ > +struct rte_flow_item_conntrack { > + uint32_t flags; > +}; > + > +/** Default mask for RTE_FLOW_ITEM_TYPE_CONNTRACK. */ > +#ifndef __cplusplus > +static const struct rte_flow_item_conntrack rte_flow_item_conntrack_mask = > { > + .flags = 0xffffffff, > +}; > +#endif > + > /** > * Matching pattern item definition. > * > @@ -2277,6 +2331,17 @@ enum rte_flow_action_type { > * same port or across different ports. > */ > RTE_FLOW_ACTION_TYPE_INDIRECT, > + > + /** > + * [META] > + * > + * Enable tracking a TCP connection state. > + * > + * Send packet to HW connection tracking module for examination. > + * > + * See struct rte_flow_action_conntrack. > + */ > + RTE_FLOW_ACTION_TYPE_CONNTRACK, > }; > > /** > @@ -2875,6 +2940,136 @@ struct rte_flow_action_set_dscp { > */ > struct rte_flow_action_handle; > > +/** > + * The state of a TCP connection. > + */ > +enum rte_flow_conntrack_state { > + /**< SYN-ACK packet was seen. */ > + RTE_FLOW_CONNTRACK_STATE_SYN_RECV, > + /**< 3-way handshark was done. */ > + RTE_FLOW_CONNTRACK_STATE_ESTABLISHED, > + /**< First FIN packet was received to close the connection. */ > + RTE_FLOW_CONNTRACK_STATE_FIN_WAIT, > + /**< First FIN was ACKed. */ > + RTE_FLOW_CONNTRACK_STATE_CLOSE_WAIT, > + /**< Second FIN was received, waiting for the last ACK. */ > + RTE_FLOW_CONNTRACK_STATE_LAST_ACK, > + /**< Second FIN was ACKed, connection was closed. */ > + RTE_FLOW_CONNTRACK_STATE_TIME_WAIT, > +}; > + > +/** > + * The last passed TCP packet flags of a connection. > + */ > +enum rte_flow_conntrack_tcp_last_index { > + RTE_FLOW_CONNTRACK_FLAG_NONE = 0, /**< No Flag. */ > + RTE_FLOW_CONNTRACK_FLAG_SYN = (1 << 0), /**< With SYN flag. */ > + RTE_FLOW_CONNTRACK_FLAG_SYNACK = (1 << 1), /**< With SYN+ACK > flag. */ > + RTE_FLOW_CONNTRACK_FLAG_FIN = (1 << 2), /**< With FIN flag. */ > + RTE_FLOW_CONNTRACK_FLAG_ACK = (1 << 3), /**< With ACK flag. */ > + RTE_FLOW_CONNTRACK_FLAG_RST = (1 << 4), /**< With RST flag. */ > +}; > + > +/** > + * @warning > + * @b EXPERIMENTAL: this structure may change without prior notice > + * > + * Configuration parameters for each direction of a TCP connection. > + */ > +struct rte_flow_tcp_dir_param { > + uint32_t scale:4; /**< TCP window scaling factor, 0xF to disable. */ > + uint32_t close_initiated:1; /**< The FIN was sent by this direction. */ > + /**< An ACK packet has been received by this side. */ > + uint32_t last_ack_seen:1; > + /**< If set, indicates that there is unacked data of the connection. */ > + uint32_t data_unacked:1; > + /**< Maximal value of sequence + payload length over sent > + * packets (next ACK from the opposite direction). > + */ > + uint32_t sent_end; > + /**< Maximal value of (ACK + window size) over received packet + > length > + * over sent packet (maximal sequence could be sent). > + */ > + uint32_t reply_end; This comment is for all members that are part of the packet, Do you think it should be in network order? I can see the advantage in both ways nice I assume the app needs this data in host byte-order but since in most other cases we use network byte-order to set values that are coming from the packet itself maybe it is better to use network byte-order (will also save the conversion) > + /**< Maximal value of actual window size over sent packets. */ > + uint32_t max_win; > + /**< Maximal value of ACK over sent packets. */ > + uint32_t max_ack; > +}; > + > +/** > + * @warning > + * @b EXPERIMENTAL: this structure may change without prior notice > + * > + * RTE_FLOW_ACTION_TYPE_CONNTRACK > + * > + * Configuration and initial state for the connection tracking module. > + * This structure could be used for both setting and query. > + */ > +struct rte_flow_action_conntrack { > + uint16_t peer_port; /**< The peer port number, can be the same port. > */ > + /**< Direction of this connection when creating a flow, the value only > + * affects the subsequent flows creation. > + */ > + uint32_t is_original_dir:1; > + /**< Enable / disable the conntrack HW module. When disabled, the > + * result will always be RTE_FLOW_CONNTRACK_FLAG_DISABLED. > + * In this state the HW will act as passthrough. > + * It only affects this conntrack object in the HW without any effect > + * to the other objects. > + */ > + uint32_t enable:1; > + /**< At least one ack was seen, after the connection was established. > */ > + uint32_t live_connection:1; > + /**< Enable selective ACK on this connection. */ > + uint32_t selective_ack:1; > + /**< A challenge ack has passed. */ > + uint32_t challenge_ack_passed:1; > + /**< 1: The last packet is seen that comes from the original direction. > + * 0: From the reply direction. > + */ > + uint32_t last_direction:1; > + /**< No TCP check will be done except the state change. */ > + uint32_t liberal_mode:1; > + /**< The current state of the connection. */ > + enum rte_flow_conntrack_state state; > + /**< Scaling factor for maximal allowed ACK window. */ > + uint8_t max_ack_window; > + /**< Maximal allowed number of retransmission times. */ > + uint8_t retransmission_limit; > + /**< TCP parameters of the original direction. */ > + struct rte_flow_tcp_dir_param original_dir; > + /**< TCP parameters of the reply direction. */ > + struct rte_flow_tcp_dir_param reply_dir; > + /**< The window value of the last packet passed this conntrack. */ > + uint16_t last_window; > + enum rte_flow_conntrack_tcp_last_index last_index; > + /**< The sequence of the last packet passed this conntrack. */ > + uint32_t last_seq; > + /**< The acknowledgement of the last packet passed this conntrack. */ > + uint32_t last_ack; > + /**< The total value ACK + payload length of the last packet passed > + * this conntrack. > + */ > + uint32_t last_end; > +}; > + > +/** > + * RTE_FLOW_ACTION_TYPE_CONNTRACK > + * > + * Wrapper structure for the context update interface. > + * Ports cannot support updating, and the only valid solution is to > + * destroy the old context and create a new one instead. > + */ > +struct rte_flow_modify_conntrack { > + /**< New connection tracking parameters to be updated. */ > + struct rte_flow_action_conntrack new_ct; > + uint32_t direction:1; /**< The direction field will be updated. */ > + /**< All the other fields except direction will be updated. */ > + uint32_t state:1; > + uint32_t reserved:30; /**< Reserved bits for the future usage. */ > +}; > + > /** > * Field IDs for MODIFY_FIELD action. > */ > -- > 2.19.0.windows.1
