vpp - Vector Packet Processing

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author	Neale Ranns <nranns@cisco.com>	2018-12-06 13:46:49 +0000
committer	Damjan Marion <dmarion@me.com>	2018-12-07 15:09:37 +0000
commit	521a8d7df423a0b5aaf259d49ca9230705bc25ee (patch)
tree	12559229002f31b289adb15460b967a3d10900f3 /docs/reference/cmdreference/index.rst
parent	ab86f86e7c29393fa1da81b5f86296bd5fcb7420 (diff)

FIB recusrion loop checks traverse midchain adjacencies

if a tunnel's destination address is reachable through the tunnel (see example config belwo) then search for and detect a recursion loop and don't stack the adjacency. Otherwise this results in a nasty surprise. DBGvpp# loop cre DBGvpp# set int state loop0 up DBGvpp# set int ip addr loop0 10.0.0.1/24 DBGvpp# create gre tunnel src 10.0.0.1 dst 1.1.1.1 DBGvpp# set int state gre0 up DBGvpp# set int unnum gre0 use loop0 DBGvpp# ip route 1.1.1.1/32 via gre0 DBGvpp# sh ip fib 1.1.1.1 ipv4-VRF:0, fib_index:0, flow hash:[src dst sport dport proto ] locks:[src:plugin-hi:2, src:default-route:1, ] 1.1.1.1/32 fib:0 index:11 locks:4 <<< this is entry #11 src:CLI refs:1 entry-flags:attached, src-flags:added,contributing,active, path-list:[14] locks:2 flags:shared,looped, uPRF-list:12 len:1 itfs:[2, ] path:[14] pl-index:14 ip4 weight=1 pref=0 attached-nexthop: oper-flags:recursive-loop,resolved, cfg-flags:attached, 1.1.1.1 gre0 (p2p) [@0]: ipv4 via 0.0.0.0 gre0: mtu:9000 4500000000000000fe2fb0cc0a0000010101010100000800 stacked-on entry:11: <<<< and the midchain forwards via entry #11 [@2]: dpo-drop ip4 src:recursive-resolution refs:1 src-flags:added, cover:-1 forwarding: unicast-ip4-chain [@0]: dpo-load-balance: [proto:ip4 index:13 buckets:1 uRPF:12 to:[0:0]] [0] [@6]: ipv4 via 0.0.0.0 gre0: mtu:9000 4500000000000000fe2fb0cc0a0000010101010100000800 stacked-on entry:11: [@2]: dpo-drop ip4 DBGvpp# sh adj 1 [@1] ipv4 via 0.0.0.0 gre0: mtu:9000 4500000000000000fe2fb0cc0a0000010101010100000800 stacked-on entry:11: [@2]: dpo-drop ip4 flags:midchain-ip-stack midchain-looped <<<<< this is a loop counts:[0:0] locks:4 delegates: children: {path:14} Change-Id: I39b82bd1ea439be4611c88b130d40289fa0c1b59 Signed-off-by: Neale Ranns <nranns@cisco.com>

Diffstat (limited to 'docs/reference/cmdreference/index.rst')

0 files changed, 0 insertions, 0 deletions

;;; plugin-node-skel.el - vpp engine plug-in "node.c" skeleton ;;; ;;; Copyright (c) 2016 Cisco and/or its affiliates. ;;; Licensed under the Apache License, Version 2.0 (the "License"); ;;; you may not use this file except in compliance with the License. ;;; You may obtain a copy of the License at: ;;; ;;; http://www.apache.org/licenses/LICENSE-2.0 ;;; ;;; Unless required by applicable law or agreed to in writing, software ;;; distributed under the License is distributed on an "AS IS" BASIS, ;;; WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. ;;; See the License for the specific language governing permissions and ;;; limitations under the License. (require 'skeleton) (define-skeleton skel-plugin-node "Insert a plug-in 'node.c' skeleton " nil '(if (not (boundp 'plugin-name)) (setq plugin-name (read-string "Plugin name: "))) '(setq PLUGIN-NAME (upcase plugin-name)) " /* * node.c - skeleton vpp engine plug-in dual-loop node skeleton * * Copyright (c) <current-year> <your-organization> * Licensed under the Apache License, Version 2.0 (the \"License\"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at: * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an \"AS IS\" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ #include <vlib/vlib.h> #include <vnet/vnet.h> #include <vnet/pg/pg.h> #include <vppinfra/error.h> #include <" plugin-name "/" plugin-name ".h> typedef struct { u32 next_index; u32 sw_if_index; } " plugin-name "_trace_t; /* packet trace format function */ static u8 * format_" plugin-name "_trace (u8 * s, va_list * args) { CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *); CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *); " plugin-name "_trace_t * t = va_arg (*args, " plugin-name "_trace_t *); s = format (s, \"" PLUGIN-NAME ": sw_if_index %d, next index %d\", t->sw_if_index, t->next_index); return s; } vlib_node_registration_t " plugin-name "_node; #define foreach_" plugin-name "_error \\ _(SWAPPED, \"Mac swap packets processed\") typedef enum { #define _(sym,str) " PLUGIN-NAME "_ERROR_##sym, foreach_" plugin-name "_error #undef _ " PLUGIN-NAME "_N_ERROR, } " plugin-name "_error_t; static char * " plugin-name "_error_strings[] = { #define _(sym,string) string, foreach_" plugin-name "_error #undef _ }; typedef enum { " PLUGIN-NAME "_NEXT_INTERFACE_OUTPUT, " PLUGIN-NAME "_N_NEXT, } " plugin-name "_next_t; #define foreach_mac_address_offset \\ _(0) \\ _(1) \\ _(2) \\ _(3) \\ _(4) \\ _(5) static uword " plugin-name "_node_fn (vlib_main_t * vm, vlib_node_runtime_t * node, vlib_frame_t * frame) { u32 n_left_from, * from, * to_next; " plugin-name "_next_t next_index; u32 pkts_swapped = 0; from = vlib_frame_vector_args (frame); n_left_from = frame->n_vectors; next_index = node->cached_next_index; while (n_left_from > 0) { u32 n_left_to_next; vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next); while (n_left_from >= 4 && n_left_to_next >= 2) { u32 next0 = " PLUGIN-NAME "_NEXT_INTERFACE_OUTPUT; u32 next1 = " PLUGIN-NAME "_NEXT_INTERFACE_OUTPUT; u32 sw_if_index0, sw_if_index1; u8 tmp0[6], tmp1[6]; ethernet_header_t *en0, *en1; u32 bi0, bi1; vlib_buffer_t * b0, * b1; /* Prefetch next iteration. */ { vlib_buffer_t * p2, * p3; p2 = vlib_get_buffer (vm, from[2]); p3 = vlib_get_buffer (vm, from[3]); vlib_prefetch_buffer_header (p2, LOAD); vlib_prefetch_buffer_header (p3, LOAD); CLIB_PREFETCH (p2->data, CLIB_CACHE_LINE_BYTES, STORE); CLIB_PREFETCH (p3->data, CLIB_CACHE_LINE_BYTES, STORE); } /* speculatively enqueue b0 and b1 to the current next frame */ to_next[0] = bi0 = from[0]; to_next[1] = bi1 = from[1]; from += 2; to_next += 2; n_left_from -= 2; n_left_to_next -= 2; b0 = vlib_get_buffer (vm, bi0); b1 = vlib_get_buffer (vm, bi1); ASSERT (b0->current_data == 0); ASSERT (b1->current_data == 0); en0 = vlib_buffer_get_current (b0); en1 = vlib_buffer_get_current (b1); /* This is not the fastest way to swap src + dst mac addresses */ #define _(a) tmp0[a] = en0->src_address[a]; foreach_mac_address_offset; #undef _ #define _(a) en0->src_address[a] = en0->dst_address[a]; foreach_mac_address_offset; #undef _ #define _(a) en0->dst_address[a] = tmp0[a]; foreach_mac_address_offset; #undef _ #define _(a) tmp1[a] = en1->src_address[a]; foreach_mac_address_offset; #undef _ #define _(a) en1->src_address[a] = en1->dst_address[a]; foreach_mac_address_offset; #undef _ #define _(a) en1->dst_address[a] = tmp1[a]; foreach_mac_address_offset; #undef _ sw_if_index0 = vnet_buffer(b0)->sw_if_index[VLIB_RX]; sw_if_index1 = vnet_buffer(b1)->sw_if_index[VLIB_RX]; /* Send pkt back out the RX interface */ vnet_buffer(b0)->sw_if_index[VLIB_TX] = sw_if_index0; vnet_buffer(b1)->sw_if_index[VLIB_TX] = sw_if_index1; pkts_swapped += 2; if (PREDICT_FALSE((node->flags & VLIB_NODE_FLAG_TRACE))) { if (b0->flags & VLIB_BUFFER_IS_TRACED) { " plugin-name "_trace_t *t = vlib_add_trace (vm, node, b0, sizeof (*t)); t->sw_if_index = sw_if_index0; t->next_index = next0; } if (b1->flags & VLIB_BUFFER_IS_TRACED) { " plugin-name "_trace_t *t = vlib_add_trace (vm, node, b1, sizeof (*t)); t->sw_if_index = sw_if_index1; t->next_index = next1; } } /* verify speculative enqueues, maybe switch current next frame */ vlib_validate_buffer_enqueue_x2 (vm, node, next_index, to_next, n_left_to_next, bi0, bi1, next0, next1); } while (n_left_from > 0 && n_left_to_next > 0) { u32 bi0; vlib_buffer_t * b0; u32 next0 = " PLUGIN-NAME "_NEXT_INTERFACE_OUTPUT; u32 sw_if_index0; u8 tmp0[6]; ethernet_header_t *en0; /* speculatively enqueue b0 to the current next frame */ bi0 = from[0]; to_next[0] = bi0; from += 1; to_next += 1; n_left_from -= 1; n_left_to_next -= 1; b0 = vlib_get_buffer (vm, bi0); /* * Direct from the driver, we should be at offset 0 * aka at &b0->data[0] */ ASSERT (b0->current_data == 0); en0 = vlib_buffer_get_current (b0); /* This is not the fastest way to swap src + dst mac addresses */ #define _(a) tmp0[a] = en0->src_address[a]; foreach_mac_address_offset; #undef _ #define _(a) en0->src_address[a] = en0->dst_address[a]; foreach_mac_address_offset; #undef _ #define _(a) en0->dst_address[a] = tmp0[a]; foreach_mac_address_offset; #undef _ sw_if_index0 = vnet_buffer(b0)->sw_if_index[VLIB_RX]; /* Send pkt back out the RX interface */ vnet_buffer(b0)->sw_if_index[VLIB_TX] = sw_if_index0; if (PREDICT_FALSE((node->flags & VLIB_NODE_FLAG_TRACE) && (b0->flags & VLIB_BUFFER_IS_TRACED))) { " plugin-name "_trace_t *t = vlib_add_trace (vm, node, b0, sizeof (*t)); t->sw_if_index = sw_if_index0; t->next_index = next0; } pkts_swapped += 1; /* verify speculative enqueue, maybe switch current next frame */ vlib_validate_buffer_enqueue_x1 (vm, node, next_index, to_next, n_left_to_next, bi0, next0); } vlib_put_next_frame (vm, node, next_index, n_left_to_next); } vlib_node_increment_counter (vm, " plugin-name "_node.index, " PLUGIN-NAME "_ERROR_SWAPPED, pkts_swapped); return frame->n_vectors; } VLIB_REGISTER_NODE (" plugin-name "_node) = { .function = " plugin-name "_node_fn, .name = \"" plugin-name "\", .vector_size = sizeof (u32), .format_trace = format_" plugin-name "_trace, .type = VLIB_NODE_TYPE_INTERNAL, .n_errors = ARRAY_LEN(" plugin-name "_error_strings), .error_strings = " plugin-name "_error_strings, .n_next_nodes = " PLUGIN-NAME "_N_NEXT, /* edit / add dispositions here */ .next_nodes = { [" PLUGIN-NAME "_NEXT_INTERFACE_OUTPUT] = \"interface-output\", }, }; ")


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