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diff --git a/doc/guides/sample_app_ug/flow_filtering.rst b/doc/guides/sample_app_ug/flow_filtering.rst new file mode 100644 index 00000000..725dcb44 --- /dev/null +++ b/doc/guides/sample_app_ug/flow_filtering.rst @@ -0,0 +1,545 @@ +.. BSD LICENSE + Copyright(c) 2017 Mellanox Corporation. All rights reserved. + All rights reserved. + + Redistribution and use in source and binary forms, with or without + modification, are permitted provided that the following conditions + are met: + + * Redistributions of source code must retain the above copyright + notice, this list of conditions and the following disclaimer. + * Redistributions in binary form must reproduce the above copyright + notice, this list of conditions and the following disclaimer in + the documentation and/or other materials provided with the + distribution. + * Neither the name of Mellanox Corporation nor the names of its + contributors may be used to endorse or promote products derived + from this software without specific prior written permission. + + THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR + A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT + OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, + SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT + LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE + OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + + +Basic RTE Flow Filtering Sample Application +=========================================== + +The Basic RTE flow filtering sample application is a simple example of a +creating a RTE flow rule. + +It is intended as a demonstration of the basic components RTE flow rules. + + +Compiling the Application +------------------------- + +To compile the application export the path to the DPDK source tree and go to +the example directory: + +.. code-block:: console + + export RTE_SDK=/path/to/rte_sdk + + cd ${RTE_SDK}/examples/flow_filtering + +Set the target, for example: + +.. code-block:: console + + export RTE_TARGET=x86_64-native-linuxapp-gcc + +See the *DPDK Getting Started* Guide for possible ``RTE_TARGET`` values. + +Build the application as follows: + +.. code-block:: console + + make + + +Running the Application +----------------------- + +To run the example in a ``linuxapp`` environment: + +.. code-block:: console + + ./build/flow -l 1 -n 1 + +Refer to *DPDK Getting Started Guide* for general information on running +applications and the Environment Abstraction Layer (EAL) options. + + +Explanation +----------- + +The example is build from 2 main files, +``main.c`` which holds the example logic and ``flow_blocks.c`` that holds the +implementation for building the flow rule. + +The following sections provide an explanation of the main components of the +code. + +All DPDK library functions used in the sample code are prefixed with ``rte_`` +and are explained in detail in the *DPDK API Documentation*. + + +The Main Function +~~~~~~~~~~~~~~~~~ + +The ``main()`` function located in ``main.c`` file performs the initialization +and runs the main loop function. + +The first task is to initialize the Environment Abstraction Layer (EAL). The +``argc`` and ``argv`` arguments are provided to the ``rte_eal_init()`` +function. The value returned is the number of parsed arguments: + +.. code-block:: c + + int ret = rte_eal_init(argc, argv); + if (ret < 0) + rte_exit(EXIT_FAILURE, "Error with EAL initialization\n"); + + +The ``main()`` also allocates a mempool to hold the mbufs (Message Buffers) +used by the application: + +.. code-block:: c + + mbuf_pool = rte_pktmbuf_pool_create("mbuf_pool", 4096, 128, 0, + RTE_MBUF_DEFAULT_BUF_SIZE, + rte_socket_id()); + +Mbufs are the packet buffer structure used by DPDK. They are explained in +detail in the "Mbuf Library" section of the *DPDK Programmer's Guide*. + +The ``main()`` function also initializes all the ports using the user defined +``init_port()`` function which is explained in the next section: + +.. code-block:: c + + init_port(); + +Once the initialization is complete, we set the flow rule using the +following code: + +.. code-block:: c + + /* create flow for send packet with */ + flow = generate_ipv4_flow(port_id, selected_queue, + SRC_IP, EMPTY_MASK, + DEST_IP, FULL_MASK, &error); + if (!flow) { + printf("Flow can't be created %d message: %s\n", + error.type, + error.message ? error.message : "(no stated reason)"); + rte_exit(EXIT_FAILURE, "error in creating flow"); + } + +In the last part the application is ready to launch the +``main_loop()`` function. Which is explained below. + + +.. code-block:: c + + main_loop(); + +The Port Initialization Function +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + +The main functional part of the port initialization used in the flow filtering +application is shown below: + +.. code-block:: c + + init_port(void) + { + int ret; + uint16_t i; + struct rte_eth_conf port_conf = { + .rxmode = { + .split_hdr_size = 0, + /**< Header Split disabled */ + .header_split = 0, + /**< IP checksum offload disabled */ + .hw_ip_checksum = 0, + /**< VLAN filtering disabled */ + .hw_vlan_filter = 0, + /**< Jumbo Frame Support disabled */ + .jumbo_frame = 0, + /**< CRC stripped by hardware */ + .hw_strip_crc = 1, + }, + }; + + printf(":: initializing port: %d\n", port_id); + ret = rte_eth_dev_configure(port_id, + nr_queues, nr_queues, &port_conf); + if (ret < 0) { + rte_exit(EXIT_FAILURE, + ":: cannot configure device: err=%d, port=%u\n", + ret, port_id); + } + + /* only set Rx queues: something we care only so far */ + for (i = 0; i < nr_queues; i++) { + ret = rte_eth_rx_queue_setup(port_id, i, 512, + rte_eth_dev_socket_id(port_id), + NULL, + mbuf_pool); + if (ret < 0) { + rte_exit(EXIT_FAILURE, + ":: Rx queue setup failed: err=%d, port=%u\n", + ret, port_id); + } + } + + + rte_eth_promiscuous_enable(port_id); + + ret = rte_eth_dev_start(port_id); + if (ret < 0) { + rte_exit(EXIT_FAILURE, + "rte_eth_dev_start:err=%d, port=%u\n", + ret, port_id); + } + + assert_link_status(); + + printf(":: initializing port: %d done\n", port_id); + } + +The Ethernet port is configured with default settings using the +``rte_eth_dev_configure()`` function and the ``port_conf_default`` struct: + +.. code-block:: c + + struct rte_eth_conf port_conf = { + .rxmode = { + .split_hdr_size = 0, + /**< Header Split disabled */ + .header_split = 0, + /**< IP checksum offload disabled */ + .hw_ip_checksum = 0, + /**< VLAN filtering disabled */ + .hw_vlan_filter = 0, + /**< Jumbo Frame Support disabled */ + .jumbo_frame = 0, + /**< CRC stripped by hardware */ + .hw_strip_crc = 1, + }, + }; + + ret = rte_eth_dev_configure(port_id, nr_queues, nr_queues, &port_conf); + if (ret < 0) { + rte_exit(EXIT_FAILURE, + ":: cannot configure device: err=%d, port=%u\n", + ret, port_id); + } + +For this example we are configuring number of rx queues that are connected to +a single port. + +.. code-block:: c + + for (i = 0; i < nr_queues; i++) { + ret = rte_eth_rx_queue_setup(port_id, i, 512, + rte_eth_dev_socket_id(port_id), + NULL, + mbuf_pool); + if (ret < 0) { + rte_exit(EXIT_FAILURE, + ":: Rx queue setup failed: err=%d, port=%u\n", + ret, port_id); + } + } + +In the next step we create and apply the flow rule. which is to send packets +with destination ip equals to 192.168.1.1 to queue number 1. The detail +explanation of the ``generate_ipv4_flow()`` appears later in this document: + +.. code-block:: c + + flow = generate_ipv4_flow(port_id, selected_queue, + SRC_IP, EMPTY_MASK, + DEST_IP, FULL_MASK, &error); + +We are setting the RX port to promiscuous mode: + +.. code-block:: c + + rte_eth_promiscuous_enable(port_id); + +The last step is to start the port. + +.. code-block:: c + + ret = rte_eth_dev_start(port_id); + if (ret < 0) { + rte_exit(EXIT_FAILURE, "rte_eth_dev_start:err%d, port=%u\n", + ret, port_id); + } + + +The main_loop function +~~~~~~~~~~~~~~~~~~~~~~ + +As we saw above the ``main()`` function calls an application function to handle +the main loop. For the flow filtering application the main_loop function +looks like the following: + +.. code-block:: c + + static void + main_loop(void) + { + struct rte_mbuf *mbufs[32]; + struct ether_hdr *eth_hdr; + uint16_t nb_rx; + uint16_t i; + uint16_t j; + + while (!force_quit) { + for (i = 0; i < nr_queues; i++) { + nb_rx = rte_eth_rx_burst(port_id, + i, mbufs, 32); + if (nb_rx) { + for (j = 0; j < nb_rx; j++) { + struct rte_mbuf *m = mbufs[j]; + + eth_hdr = rte_pktmbuf_mtod(m, + struct ether_hdr *); + print_ether_addr("src=", + ð_hdr->s_addr); + print_ether_addr(" - dst=", + ð_hdr->d_addr); + printf(" - queue=0x%x", + (unsigned int)i); + printf("\n"); + rte_pktmbuf_free(m); + } + } + } + } + /* closing and releasing resources */ + rte_flow_flush(port_id, &error); + rte_eth_dev_stop(port_id); + rte_eth_dev_close(port_id); + } + +The main work of the application is reading the packets from all +queues and printing for each packet the destination queue: + +.. code-block:: c + + while (!force_quit) { + for (i = 0; i < nr_queues; i++) { + nb_rx = rte_eth_rx_burst(port_id, i, mbufs, 32); + if (nb_rx) { + for (j = 0; j < nb_rx; j++) { + struct rte_mbuf *m = mbufs[j]; + eth_hdr = rte_pktmbuf_mtod(m, struct ether_hdr *); + print_ether_addr("src=", ð_hdr->s_addr); + print_ether_addr(" - dst=", ð_hdr->d_addr); + printf(" - queue=0x%x", (unsigned int)i); + printf("\n"); + rte_pktmbuf_free(m); + } + } + } + } + + +The forwarding loop can be interrupted and the application closed using +``Ctrl-C``. Which results in closing the port and the device using +``rte_eth_dev_stop`` and ``rte_eth_dev_close`` + +The generate_ipv4_flow function +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + +The generate_ipv4_rule function is responsible for creating the flow rule. +This function is located in the ``flow_blocks.c`` file. + +.. code-block:: c + + static struct rte_flow * + generate_ipv4_flow(uint8_t port_id, uint16_t rx_q, + uint32_t src_ip, uint32_t src_mask, + uint32_t dest_ip, uint32_t dest_mask, + struct rte_flow_error *error) + { + struct rte_flow_attr attr; + struct rte_flow_item pattern[MAX_PATTERN_NUM]; + struct rte_flow_action action[MAX_PATTERN_NUM]; + struct rte_flow *flow = NULL; + struct rte_flow_action_queue queue = { .index = rx_q }; + struct rte_flow_item_eth eth_spec; + struct rte_flow_item_eth eth_mask; + struct rte_flow_item_vlan vlan_spec; + struct rte_flow_item_vlan vlan_mask; + struct rte_flow_item_ipv4 ip_spec; + struct rte_flow_item_ipv4 ip_mask; + + memset(pattern, 0, sizeof(pattern)); + memset(action, 0, sizeof(action)); + + /* + * set the rule attribute. + * in this case only ingress packets will be checked. + */ + memset(&attr, 0, sizeof(struct rte_flow_attr)); + attr.ingress = 1; + + /* + * create the action sequence. + * one action only, move packet to queue + */ + + action[0].type = RTE_FLOW_ACTION_TYPE_QUEUE; + action[0].conf = &queue; + action[1].type = RTE_FLOW_ACTION_TYPE_END; + + /* + * set the first level of the pattern (eth). + * since in this example we just want to get the + * ipv4 we set this level to allow all. + */ + memset(ð_spec, 0, sizeof(struct rte_flow_item_eth)); + memset(ð_mask, 0, sizeof(struct rte_flow_item_eth)); + eth_spec.type = 0; + eth_mask.type = 0; + pattern[0].type = RTE_FLOW_ITEM_TYPE_ETH; + pattern[0].spec = ð_spec; + pattern[0].mask = ð_mask; + + /* + * setting the second level of the pattern (vlan). + * since in this example we just want to get the + * ipv4 we also set this level to allow all. + */ + memset(&vlan_spec, 0, sizeof(struct rte_flow_item_vlan)); + memset(&vlan_mask, 0, sizeof(struct rte_flow_item_vlan)); + pattern[1].type = RTE_FLOW_ITEM_TYPE_VLAN; + pattern[1].spec = &vlan_spec; + pattern[1].mask = &vlan_mask; + + /* + * setting the third level of the pattern (ip). + * in this example this is the level we care about + * so we set it according to the parameters. + */ + memset(&ip_spec, 0, sizeof(struct rte_flow_item_ipv4)); + memset(&ip_mask, 0, sizeof(struct rte_flow_item_ipv4)); + ip_spec.hdr.dst_addr = htonl(dest_ip); + ip_mask.hdr.dst_addr = dest_mask; + ip_spec.hdr.src_addr = htonl(src_ip); + ip_mask.hdr.src_addr = src_mask; + pattern[2].type = RTE_FLOW_ITEM_TYPE_IPV4; + pattern[2].spec = &ip_spec; + pattern[2].mask = &ip_mask; + + /* the final level must be always type end */ + pattern[3].type = RTE_FLOW_ITEM_TYPE_END; + + int res = rte_flow_validate(port_id, &attr, pattern, action, error); + if(!res) + flow = rte_flow_create(port_id, &attr, pattern, action, error); + + return flow; + } + +The first part of the function is declaring the structures that will be used. + +.. code-block:: c + + struct rte_flow_attr attr; + struct rte_flow_item pattern[MAX_PATTERN_NUM]; + struct rte_flow_action action[MAX_PATTERN_NUM]; + struct rte_flow *flow; + struct rte_flow_error error; + struct rte_flow_action_queue queue = { .index = rx_q }; + struct rte_flow_item_eth eth_spec; + struct rte_flow_item_eth eth_mask; + struct rte_flow_item_vlan vlan_spec; + struct rte_flow_item_vlan vlan_mask; + struct rte_flow_item_ipv4 ip_spec; + struct rte_flow_item_ipv4 ip_mask; + +The following part create the flow attributes, in our case ingress. + +.. code-block:: c + + memset(&attr, 0, sizeof(struct rte_flow_attr)); + attr.ingress = 1; + +The third part defines the action to be taken when a packet matches +the rule. In this case send the packet to queue. + +.. code-block:: c + + action[0].type = RTE_FLOW_ACTION_TYPE_QUEUE; + action[0].conf = &queue; + action[1].type = RTE_FLOW_ACTION_TYPE_END; + +The forth part is responsible for creating the pattern and is build from +number of step. In each step we build one level of the pattern starting with +the lowest one. + +Setting the first level of the pattern ETH: + +.. code-block:: c + + memset(ð_spec, 0, sizeof(struct rte_flow_item_eth)); + memset(ð_mask, 0, sizeof(struct rte_flow_item_eth)); + eth_spec.type = 0; + eth_mask.type = 0; + pattern[0].type = RTE_FLOW_ITEM_TYPE_ETH; + pattern[0].spec = ð_spec; + pattern[0].mask = ð_mask; + +Setting the second level of the pattern VLAN: + +.. code-block:: c + + memset(&vlan_spec, 0, sizeof(struct rte_flow_item_vlan)); + memset(&vlan_mask, 0, sizeof(struct rte_flow_item_vlan)); + pattern[1].type = RTE_FLOW_ITEM_TYPE_VLAN; + pattern[1].spec = &vlan_spec; + pattern[1].mask = &vlan_mask; + +Setting the third level ip: + +.. code-block:: c + + memset(&ip_spec, 0, sizeof(struct rte_flow_item_ipv4)); + memset(&ip_mask, 0, sizeof(struct rte_flow_item_ipv4)); + ip_spec.hdr.dst_addr = htonl(dest_ip); + ip_mask.hdr.dst_addr = dest_mask; + ip_spec.hdr.src_addr = htonl(src_ip); + ip_mask.hdr.src_addr = src_mask; + pattern[2].type = RTE_FLOW_ITEM_TYPE_IPV4; + pattern[2].spec = &ip_spec; + pattern[2].mask = &ip_mask; + +Closing the pattern part. + +.. code-block:: c + + pattern[3].type = RTE_FLOW_ITEM_TYPE_END; + +The last part of the function is to validate the rule and create it. + +.. code-block:: c + + int res = rte_flow_validate(port_id, &attr, pattern, action, &error); + if (!res) + flow = rte_flow_create(port_id, &attr, pattern, action, &error); + |