diff options
Diffstat (limited to 'src/vnet/l2/l2_fwd.c')
-rw-r--r-- | src/vnet/l2/l2_fwd.c | 577 |
1 files changed, 577 insertions, 0 deletions
diff --git a/src/vnet/l2/l2_fwd.c b/src/vnet/l2/l2_fwd.c new file mode 100644 index 00000000..2bb7307c --- /dev/null +++ b/src/vnet/l2/l2_fwd.c @@ -0,0 +1,577 @@ +/* + * l2_fwd.c : layer 2 forwarding using l2fib + * + * Copyright (c) 2013 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. + */ + +#include <vlib/vlib.h> +#include <vnet/vnet.h> +#include <vnet/pg/pg.h> +#include <vnet/ethernet/ethernet.h> +#include <vlib/cli.h> + +#include <vnet/l2/l2_input.h> +#include <vnet/l2/l2_bvi.h> +#include <vnet/l2/l2_fwd.h> +#include <vnet/l2/l2_fib.h> + +#include <vppinfra/error.h> +#include <vppinfra/hash.h> +#include <vppinfra/sparse_vec.h> + + +/** + * @file + * @brief Ethernet Forwarding. + * + * Code in this file handles forwarding Layer 2 packets. This file calls + * the FIB lookup, packet learning and the packet flooding as necessary. + * Packet is then sent to the next graph node. + */ + +typedef struct +{ + + /* Hash table */ + BVT (clib_bihash) * mac_table; + + /* next node index for the L3 input node of each ethertype */ + next_by_ethertype_t l3_next; + + /* convenience variables */ + vlib_main_t *vlib_main; + vnet_main_t *vnet_main; +} l2fwd_main_t; + +typedef struct +{ + /* per-pkt trace data */ + u8 src[6]; + u8 dst[6]; + u32 sw_if_index; + u16 bd_index; +} l2fwd_trace_t; + +/* packet trace format function */ +static u8 * +format_l2fwd_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 *); + l2fwd_trace_t *t = va_arg (*args, l2fwd_trace_t *); + + s = format (s, "l2-fwd: sw_if_index %d dst %U src %U bd_index %d", + t->sw_if_index, + format_ethernet_address, t->dst, + format_ethernet_address, t->src, t->bd_index); + return s; +} + +l2fwd_main_t l2fwd_main; + +static vlib_node_registration_t l2fwd_node; + +#define foreach_l2fwd_error \ +_(L2FWD, "L2 forward packets") \ +_(FLOOD, "L2 forward misses") \ +_(HIT, "L2 forward hits") \ +_(BVI_BAD_MAC, "BVI L3 MAC mismatch") \ +_(BVI_ETHERTYPE, "BVI packet with unhandled ethertype") \ +_(FILTER_DROP, "Filter Mac Drop") \ +_(REFLECT_DROP, "Reflection Drop") \ +_(STALE_DROP, "Stale entry Drop") + +typedef enum +{ +#define _(sym,str) L2FWD_ERROR_##sym, + foreach_l2fwd_error +#undef _ + L2FWD_N_ERROR, +} l2fwd_error_t; + +static char *l2fwd_error_strings[] = { +#define _(sym,string) string, + foreach_l2fwd_error +#undef _ +}; + +typedef enum +{ + L2FWD_NEXT_L2_OUTPUT, + L2FWD_NEXT_FLOOD, + L2FWD_NEXT_DROP, + L2FWD_N_NEXT, +} l2fwd_next_t; + +/** Forward one packet based on the mac table lookup result. */ + +static_always_inline void +l2fwd_process (vlib_main_t * vm, + vlib_node_runtime_t * node, + l2fwd_main_t * msm, + vlib_error_main_t * em, + vlib_buffer_t * b0, + u32 sw_if_index0, l2fib_entry_result_t * result0, u32 * next0) +{ + int try_flood = result0->raw == ~0; + int flood_error; + + if (PREDICT_FALSE (try_flood)) + { + flood_error = L2FWD_ERROR_FLOOD; + } + else + { + /* lookup hit, forward packet */ +#ifdef COUNTERS + em->counters[node_counter_base_index + L2FWD_ERROR_HIT] += 1; +#endif + + vnet_buffer (b0)->sw_if_index[VLIB_TX] = result0->fields.sw_if_index; + *next0 = L2FWD_NEXT_L2_OUTPUT; + int l2fib_seq_num_valid = 1; + + /* check l2fib seq num for stale entries */ + if (!result0->fields.age_not) + { + l2fib_seq_num_t in_sn = {.as_u16 = vnet_buffer (b0)->l2.l2fib_sn }; + l2fib_seq_num_t expected_sn = { + .bd = in_sn.bd, + .swif = *l2fib_swif_seq_num (result0->fields.sw_if_index), + }; + l2fib_seq_num_valid = + expected_sn.as_u16 == result0->fields.sn.as_u16; + } + + if (PREDICT_FALSE (!l2fib_seq_num_valid)) + { + flood_error = L2FWD_ERROR_STALE_DROP; + try_flood = 1; + } + /* perform reflection check */ + else if (PREDICT_FALSE (sw_if_index0 == result0->fields.sw_if_index)) + { + b0->error = node->errors[L2FWD_ERROR_REFLECT_DROP]; + *next0 = L2FWD_NEXT_DROP; + } + /* perform filter check */ + else if (PREDICT_FALSE (result0->fields.filter)) + { + b0->error = node->errors[L2FWD_ERROR_FILTER_DROP]; + *next0 = L2FWD_NEXT_DROP; + } + /* perform BVI check */ + else if (PREDICT_FALSE (result0->fields.bvi)) + { + u32 rc; + rc = l2_to_bvi (vm, + msm->vnet_main, + b0, + vnet_buffer (b0)->sw_if_index[VLIB_TX], + &msm->l3_next, next0); + + if (PREDICT_FALSE (rc)) + { + if (rc == TO_BVI_ERR_BAD_MAC) + { + b0->error = node->errors[L2FWD_ERROR_BVI_BAD_MAC]; + *next0 = L2FWD_NEXT_DROP; + } + else if (rc == TO_BVI_ERR_ETHERTYPE) + { + b0->error = node->errors[L2FWD_ERROR_BVI_ETHERTYPE]; + *next0 = L2FWD_NEXT_DROP; + } + } + } + } + + /* flood */ + if (PREDICT_FALSE (try_flood)) + { + /* + * lookup miss, so flood + * TODO:replicate packet to each intf in bridge-domain + * For now just drop + */ + if (vnet_buffer (b0)->l2.feature_bitmap & L2INPUT_FEAT_UU_FLOOD) + { + *next0 = L2FWD_NEXT_FLOOD; + } + else + { + /* Flooding is disabled */ + b0->error = node->errors[flood_error]; + *next0 = L2FWD_NEXT_DROP; + } + } + +} + + +static_always_inline uword +l2fwd_node_inline (vlib_main_t * vm, vlib_node_runtime_t * node, + vlib_frame_t * frame, int do_trace) +{ + u32 n_left_from, *from, *to_next; + l2fwd_next_t next_index; + l2fwd_main_t *msm = &l2fwd_main; + vlib_node_t *n = vlib_get_node (vm, l2fwd_node.index); + CLIB_UNUSED (u32 node_counter_base_index) = n->error_heap_index; + vlib_error_main_t *em = &vm->error_main; + l2fib_entry_key_t cached_key; + l2fib_entry_result_t cached_result; + + /* Clear the one-entry cache in case mac table was updated */ + cached_key.raw = ~0; + cached_result.raw = ~0; + + from = vlib_frame_vector_args (frame); + n_left_from = frame->n_vectors; /* number of packets to process */ + next_index = node->cached_next_index; + + while (n_left_from > 0) + { + u32 n_left_to_next; + + /* get space to enqueue frame to graph node "next_index" */ + vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next); + + while (n_left_from >= 8 && n_left_to_next >= 4) + { + u32 bi0, bi1, bi2, bi3; + vlib_buffer_t *b0, *b1, *b2, *b3; + u32 next0, next1, next2, next3; + u32 sw_if_index0, sw_if_index1, sw_if_index2, sw_if_index3; + ethernet_header_t *h0, *h1, *h2, *h3; + l2fib_entry_key_t key0, key1, key2, key3; + l2fib_entry_result_t result0, result1, result2, result3; + u32 bucket0, bucket1, bucket2, bucket3; + + /* Prefetch next iteration. */ + { + vlib_buffer_t *p4, *p5, *p6, *p7; + + p4 = vlib_get_buffer (vm, from[4]); + p5 = vlib_get_buffer (vm, from[5]); + p6 = vlib_get_buffer (vm, from[6]); + p7 = vlib_get_buffer (vm, from[7]); + + vlib_prefetch_buffer_header (p4, LOAD); + vlib_prefetch_buffer_header (p5, LOAD); + vlib_prefetch_buffer_header (p6, LOAD); + vlib_prefetch_buffer_header (p7, LOAD); + + CLIB_PREFETCH (p4->data, CLIB_CACHE_LINE_BYTES, STORE); + CLIB_PREFETCH (p5->data, CLIB_CACHE_LINE_BYTES, STORE); + CLIB_PREFETCH (p6->data, CLIB_CACHE_LINE_BYTES, STORE); + CLIB_PREFETCH (p7->data, CLIB_CACHE_LINE_BYTES, STORE); + } + + /* speculatively enqueue b0 and b1 to the current next frame */ + /* bi is "buffer index", b is pointer to the buffer */ + to_next[0] = bi0 = from[0]; + to_next[1] = bi1 = from[1]; + to_next[2] = bi2 = from[2]; + to_next[3] = bi3 = from[3]; + from += 4; + to_next += 4; + n_left_from -= 4; + n_left_to_next -= 4; + + b0 = vlib_get_buffer (vm, bi0); + b1 = vlib_get_buffer (vm, bi1); + b2 = vlib_get_buffer (vm, bi2); + b3 = vlib_get_buffer (vm, bi3); + + /* RX interface handles */ + sw_if_index0 = vnet_buffer (b0)->sw_if_index[VLIB_RX]; + sw_if_index1 = vnet_buffer (b1)->sw_if_index[VLIB_RX]; + sw_if_index2 = vnet_buffer (b2)->sw_if_index[VLIB_RX]; + sw_if_index3 = vnet_buffer (b3)->sw_if_index[VLIB_RX]; + + h0 = vlib_buffer_get_current (b0); + h1 = vlib_buffer_get_current (b1); + h2 = vlib_buffer_get_current (b2); + h3 = vlib_buffer_get_current (b3); + + if (do_trace) + { + if (b0->flags & VLIB_BUFFER_IS_TRACED) + { + l2fwd_trace_t *t = + vlib_add_trace (vm, node, b0, sizeof (*t)); + t->sw_if_index = sw_if_index0; + t->bd_index = vnet_buffer (b0)->l2.bd_index; + clib_memcpy (t->src, h0->src_address, 6); + clib_memcpy (t->dst, h0->dst_address, 6); + } + if (b1->flags & VLIB_BUFFER_IS_TRACED) + { + l2fwd_trace_t *t = + vlib_add_trace (vm, node, b1, sizeof (*t)); + t->sw_if_index = sw_if_index1; + t->bd_index = vnet_buffer (b1)->l2.bd_index; + clib_memcpy (t->src, h1->src_address, 6); + clib_memcpy (t->dst, h1->dst_address, 6); + } + if (b2->flags & VLIB_BUFFER_IS_TRACED) + { + l2fwd_trace_t *t = + vlib_add_trace (vm, node, b2, sizeof (*t)); + t->sw_if_index = sw_if_index2; + t->bd_index = vnet_buffer (b2)->l2.bd_index; + clib_memcpy (t->src, h2->src_address, 6); + clib_memcpy (t->dst, h2->dst_address, 6); + } + if (b3->flags & VLIB_BUFFER_IS_TRACED) + { + l2fwd_trace_t *t = + vlib_add_trace (vm, node, b3, sizeof (*t)); + t->sw_if_index = sw_if_index3; + t->bd_index = vnet_buffer (b3)->l2.bd_index; + clib_memcpy (t->src, h3->src_address, 6); + clib_memcpy (t->dst, h3->dst_address, 6); + } + } + + /* process 2 pkts */ +#ifdef COUNTERS + em->counters[node_counter_base_index + L2FWD_ERROR_L2FWD] += 4; +#endif + /* *INDENT-OFF* */ + l2fib_lookup_4 (msm->mac_table, &cached_key, &cached_result, + h0->dst_address, h1->dst_address, + h2->dst_address, h3->dst_address, + vnet_buffer (b0)->l2.bd_index, + vnet_buffer (b1)->l2.bd_index, + vnet_buffer (b2)->l2.bd_index, + vnet_buffer (b3)->l2.bd_index, + &key0, /* not used */ + &key1, /* not used */ + &key2, /* not used */ + &key3, /* not used */ + &bucket0, /* not used */ + &bucket1, /* not used */ + &bucket2, /* not used */ + &bucket3, /* not used */ + &result0, + &result1, + &result2, + &result3); + /* *INDENT-ON* */ + l2fwd_process (vm, node, msm, em, b0, sw_if_index0, &result0, + &next0); + l2fwd_process (vm, node, msm, em, b1, sw_if_index1, &result1, + &next1); + l2fwd_process (vm, node, msm, em, b2, sw_if_index2, &result2, + &next2); + l2fwd_process (vm, node, msm, em, b3, sw_if_index3, &result3, + &next3); + + /* verify speculative enqueues, maybe switch current next frame */ + /* if next0==next1==next_index then nothing special needs to be done */ + vlib_validate_buffer_enqueue_x4 (vm, node, next_index, + to_next, n_left_to_next, + bi0, bi1, bi2, bi3, + next0, next1, next2, next3); + } + + while (n_left_from > 0 && n_left_to_next > 0) + { + u32 bi0; + vlib_buffer_t *b0; + u32 next0; + u32 sw_if_index0; + ethernet_header_t *h0; + l2fib_entry_key_t key0; + l2fib_entry_result_t result0; + u32 bucket0; + + /* 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); + + sw_if_index0 = vnet_buffer (b0)->sw_if_index[VLIB_RX]; + + h0 = vlib_buffer_get_current (b0); + + if (do_trace && PREDICT_FALSE (b0->flags & VLIB_BUFFER_IS_TRACED)) + { + l2fwd_trace_t *t = vlib_add_trace (vm, node, b0, sizeof (*t)); + t->sw_if_index = sw_if_index0; + t->bd_index = vnet_buffer (b0)->l2.bd_index; + clib_memcpy (t->src, h0->src_address, 6); + clib_memcpy (t->dst, h0->dst_address, 6); + } + + /* process 1 pkt */ +#ifdef COUNTERS + em->counters[node_counter_base_index + L2FWD_ERROR_L2FWD] += 1; +#endif + l2fib_lookup_1 (msm->mac_table, &cached_key, &cached_result, h0->dst_address, vnet_buffer (b0)->l2.bd_index, &key0, /* not used */ + &bucket0, /* not used */ + &result0); + l2fwd_process (vm, node, msm, em, b0, sw_if_index0, &result0, + &next0); + + /* 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); + } + + return frame->n_vectors; +} + +static uword +l2fwd_node_fn (vlib_main_t * vm, + vlib_node_runtime_t * node, vlib_frame_t * frame) +{ + if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE))) + return l2fwd_node_inline (vm, node, frame, 1 /* do_trace */ ); + return l2fwd_node_inline (vm, node, frame, 0 /* do_trace */ ); +} + +/* *INDENT-OFF* */ +VLIB_REGISTER_NODE (l2fwd_node,static) = { + .function = l2fwd_node_fn, + .name = "l2-fwd", + .vector_size = sizeof (u32), + .format_trace = format_l2fwd_trace, + .type = VLIB_NODE_TYPE_INTERNAL, + + .n_errors = ARRAY_LEN(l2fwd_error_strings), + .error_strings = l2fwd_error_strings, + + .n_next_nodes = L2FWD_N_NEXT, + + /* edit / add dispositions here */ + .next_nodes = { + [L2FWD_NEXT_L2_OUTPUT] = "l2-output", + [L2FWD_NEXT_FLOOD] = "l2-flood", + [L2FWD_NEXT_DROP] = "error-drop", + }, +}; +/* *INDENT-ON* */ + +VLIB_NODE_FUNCTION_MULTIARCH (l2fwd_node, l2fwd_node_fn) + clib_error_t *l2fwd_init (vlib_main_t * vm) +{ + l2fwd_main_t *mp = &l2fwd_main; + + mp->vlib_main = vm; + mp->vnet_main = vnet_get_main (); + + /* init the hash table ptr */ + mp->mac_table = get_mac_table (); + + /* Initialize the next nodes for each ethertype */ + next_by_ethertype_init (&mp->l3_next); + + return 0; +} + +VLIB_INIT_FUNCTION (l2fwd_init); + + +/** Add the L3 input node for this ethertype to the next nodes structure. */ +void +l2fwd_register_input_type (vlib_main_t * vm, + ethernet_type_t type, u32 node_index) +{ + l2fwd_main_t *mp = &l2fwd_main; + u32 next_index; + + next_index = vlib_node_add_next (vm, l2fwd_node.index, node_index); + + next_by_ethertype_register (&mp->l3_next, type, next_index); +} + + +/** + * Set subinterface forward enable/disable. + * The CLI format is: + * set interface l2 forward <interface> [disable] + */ +static clib_error_t * +int_fwd (vlib_main_t * vm, unformat_input_t * input, vlib_cli_command_t * cmd) +{ + vnet_main_t *vnm = vnet_get_main (); + clib_error_t *error = 0; + u32 sw_if_index; + u32 enable; + + if (!unformat_user (input, unformat_vnet_sw_interface, vnm, &sw_if_index)) + { + error = clib_error_return (0, "unknown interface `%U'", + format_unformat_error, input); + goto done; + } + + enable = 1; + if (unformat (input, "disable")) + { + enable = 0; + } + + /* set the interface flag */ + if (l2input_intf_config (sw_if_index)->xconnect) + { + l2input_intf_bitmap_enable (sw_if_index, L2INPUT_FEAT_XCONNECT, enable); + } + else + { + l2input_intf_bitmap_enable (sw_if_index, L2INPUT_FEAT_FWD, enable); + } + +done: + return error; +} + +/*? + * Layer 2 unicast forwarding can be enabled and disabled on each + * interface and on each bridge-domain. Use this command to + * manage interfaces. It is enabled by default. + * + * @cliexpar + * Example of how to enable fowarding: + * @cliexcmd{set interface l2 forward GigabitEthernet0/8/0} + * Example of how to disable fowarding: + * @cliexcmd{set interface l2 forward GigabitEthernet0/8/0 disable} +?*/ +/* *INDENT-OFF* */ +VLIB_CLI_COMMAND (int_fwd_cli, static) = { + .path = "set interface l2 forward", + .short_help = "set interface l2 forward <interface> [disable]", + .function = int_fwd, +}; +/* *INDENT-ON* */ + +/* + * fd.io coding-style-patch-verification: ON + * + * Local Variables: + * eval: (c-set-style "gnu") + * End: + */ |