diff options
Diffstat (limited to 'vnet/vnet/l2/l2_efp_filter.c')
| -rw-r--r-- | vnet/vnet/l2/l2_efp_filter.c | 572 |
1 files changed, 572 insertions, 0 deletions
diff --git a/vnet/vnet/l2/l2_efp_filter.c b/vnet/vnet/l2/l2_efp_filter.c new file mode 100644 index 00000000000..a8bceca13fe --- /dev/null +++ b/vnet/vnet/l2/l2_efp_filter.c @@ -0,0 +1,572 @@ +/* + * l2_efp_filter.c : layer 2 egress EFP Filter processing + * + * 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/ethernet/ethernet.h> +#include <vnet/ethernet/packet.h> +#include <vnet/l2/feat_bitmap.h> +#include <vnet/l2/l2_output.h> +#include <vnet/ethernet/ethernet.h> + +#include <vppinfra/error.h> +#include <vppinfra/cache.h> + +typedef struct { + + // Next nodes for features and output interfaces + l2_output_next_nodes_st next_nodes; + + /* convenience variables */ + vlib_main_t * vlib_main; + vnet_main_t * vnet_main; +} l2_efp_filter_main_t; + + +typedef struct { + /* per-pkt trace data */ + u8 src[6]; + u8 dst[6]; + u8 raw[12]; // raw data (vlans) + u32 sw_if_index; +} l2_efp_filter_trace_t; + +/* packet trace format function */ +static u8 * format_l2_efp_filter_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 *); + l2_efp_filter_trace_t * t = va_arg (*args, l2_efp_filter_trace_t *); + + s = format (s, "l2-output-vtr: sw_if_index %d dst %U src %U data " + "%02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x", + t->sw_if_index, + format_ethernet_address, t->dst, + format_ethernet_address, t->src, + t->raw[0], t->raw[1], t->raw[2], t->raw[3], t->raw[4], t->raw[5], + t->raw[6], t->raw[7], t->raw[8], t->raw[9], t->raw[10], t->raw[11]); + return s; +} + +l2_efp_filter_main_t l2_efp_filter_main; + +static vlib_node_registration_t l2_efp_filter_node; + +#define foreach_l2_efp_filter_error \ +_(L2_EFP_FILTER, "L2 EFP filter packets") \ +_(DROP, "L2 EFP filter post-rewrite drops") + +typedef enum { +#define _(sym,str) L2_EFP_FILTER_ERROR_##sym, + foreach_l2_efp_filter_error +#undef _ + L2_EFP_FILTER_N_ERROR, +} l2_efp_filter_error_t; + +static char * l2_efp_filter_error_strings[] = { +#define _(sym,string) string, + foreach_l2_efp_filter_error +#undef _ +}; + +typedef enum { + L2_EFP_FILTER_NEXT_DROP, + L2_EFP_FILTER_N_NEXT, +} l2_efp_filter_next_t; + + +// Extract fields from the packet that will be used in interface classification +static_always_inline void +extract_keys (vnet_main_t * vnet_main, + u32 sw_if_index0, + vlib_buffer_t * b0, + u32 * port_sw_if_index0, + u16 * first_ethertype0, + u16 * outer_id0, + u16 * inner_id0, + u32 * match_flags0) +{ + ethernet_header_t * e0; + ethernet_vlan_header_t * h0; + u32 tag_len; + u32 tag_num; + + *port_sw_if_index0 = vnet_get_sup_sw_interface (vnet_main, sw_if_index0)->sw_if_index; + + e0 = vlib_buffer_get_current (b0); + h0 = (ethernet_vlan_header_t *)(e0+1); + + *first_ethertype0 = clib_net_to_host_u16(e0->type); + *outer_id0 = clib_net_to_host_u16 (h0[0].priority_cfi_and_id); + *inner_id0 = clib_net_to_host_u16 (h0[1].priority_cfi_and_id); + + tag_len = vnet_buffer(b0)->l2.l2_len - sizeof(ethernet_header_t); + tag_num = tag_len / sizeof(ethernet_vlan_header_t); + *match_flags0 = eth_create_valid_subint_match_flags (tag_num); +} + +/* + * EFP filtering is a basic switch feature which prevents an interface from + * transmitting a packet that doesn't match the interface's ingress match + * criteria. The check has two parts, one performed before egress vlan tag + * rewrite and one after. + * + * The pre-rewrite check insures the packet matches what an ingress packet looks + * like after going through the interface's ingress tag rewrite operation. Only + * pushed tags are compared. So: + * - if the ingress vlan tag rewrite pushes no tags (or is not enabled), + * any packet passes the filter + * - if the ingress vlan tag rewrite pushes one tag, + * the packet must have at least one tag, and the outer tag must match the pushed tag + * - if the ingress vlan tag rewrite pushes two tags, + * the packet must have at least two tags, and the outer two tags must match the pushed tags + * + * The pre-rewrite check is performed in the l2-output node. + * + * The post-rewrite check insures the packet matches what an ingress packet looks + * like before going through the interface's ingress tag rewrite operation. It verifies + * that such a packet arriving on the wire at this port would be classified as arriving + * an input interface equal to the packet's output interface. This can be done by running + * the output packet's vlan tags and output port through the interface classification, + * and checking if the resulting interface matches the output interface. + * + * The post-rewrite check is performed here. + */ + +static uword +l2_efp_filter_node_fn (vlib_main_t * vm, + vlib_node_runtime_t * node, + vlib_frame_t * frame) +{ + u32 n_left_from, * from, * to_next; + l2_efp_filter_next_t next_index; + l2_efp_filter_main_t * msm = &l2_efp_filter_main; + vlib_node_t *n = vlib_get_node (vm, l2_efp_filter_node.index); + u32 node_counter_base_index = n->error_heap_index; + vlib_error_main_t * em = &vm->error_main; + u32 cached_sw_if_index = ~0; + u32 cached_next_index = ~0; + + /* invalidate cache to begin with */ + cached_sw_if_index = ~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 >= 6 && n_left_to_next >= 2) + { + u32 bi0, bi1; + vlib_buffer_t * b0, * b1; + u32 next0, next1; + u32 sw_if_index0, sw_if_index1; + u32 feature_bitmap0, feature_bitmap1; + u16 first_ethertype0, first_ethertype1; + u16 outer_id0, inner_id0, outer_id1, inner_id1; + u32 match_flags0, match_flags1; + u32 port_sw_if_index0, subint_sw_if_index0, port_sw_if_index1, subint_sw_if_index1; + vnet_hw_interface_t * hi0, * hi1; + main_intf_t * main_intf0, * main_intf1; + vlan_intf_t * vlan_intf0, * vlan_intf1; + qinq_intf_t * qinq_intf0, * qinq_intf1; + u32 is_l20, is_l21; + __attribute__((unused)) u32 matched0, matched1; + u8 error0, error1; + + /* Prefetch next iteration. */ + { + vlib_buffer_t * p2, * p3, * p4, * p5; + __attribute__((unused)) u32 sw_if_index2, sw_if_index3; + + p2 = vlib_get_buffer (vm, from[2]); + p3 = vlib_get_buffer (vm, from[3]); + p4 = vlib_get_buffer (vm, from[4]); + p5 = vlib_get_buffer (vm, from[5]); + + // Prefetch the buffer header and packet for the N+2 loop iteration + vlib_prefetch_buffer_header (p4, LOAD); + vlib_prefetch_buffer_header (p5, LOAD); + + CLIB_PREFETCH (p4->data, CLIB_CACHE_LINE_BYTES, STORE); + CLIB_PREFETCH (p5->data, CLIB_CACHE_LINE_BYTES, STORE); + + // Prefetch the input config for the N+1 loop iteration + // This depends on the buffer header above + sw_if_index2 = vnet_buffer(p2)->sw_if_index[VLIB_TX]; + sw_if_index3 = vnet_buffer(p3)->sw_if_index[VLIB_TX]; + //TODO CLIB_PREFETCH (vec_elt_at_index(l2output_main.configs, sw_if_index2), CLIB_CACHE_LINE_BYTES, LOAD); + //TODO CLIB_PREFETCH (vec_elt_at_index(l2output_main.configs, sw_if_index3), CLIB_CACHE_LINE_BYTES, LOAD); + } + + /* 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]; + 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); + + /* TX interface handles */ + sw_if_index0 = vnet_buffer(b0)->sw_if_index[VLIB_TX]; + sw_if_index1 = vnet_buffer(b1)->sw_if_index[VLIB_TX]; + + // process 2 packets + em->counters[node_counter_base_index + L2_EFP_FILTER_ERROR_L2_EFP_FILTER] += 2; + + // Remove ourself from the feature bitmap + feature_bitmap0 = vnet_buffer(b0)->l2.feature_bitmap & ~L2OUTPUT_FEAT_EFP_FILTER; + feature_bitmap1 = vnet_buffer(b1)->l2.feature_bitmap & ~L2OUTPUT_FEAT_EFP_FILTER; + + // Determine next node + l2_output_dispatch (msm->vlib_main, + msm->vnet_main, + node, + l2_efp_filter_node.index, + &cached_sw_if_index, + &cached_next_index, + &msm->next_nodes, + b0, + sw_if_index0, + feature_bitmap0, + &next0); + l2_output_dispatch (msm->vlib_main, + msm->vnet_main, + node, + l2_efp_filter_node.index, + &cached_sw_if_index, + &cached_next_index, + &msm->next_nodes, + b1, + sw_if_index1, + feature_bitmap1, + &next1); + + // perform the efp filter check on two packets + + extract_keys (msm->vnet_main, + sw_if_index0, + b0, + &port_sw_if_index0, + &first_ethertype0, + &outer_id0, + &inner_id0, + &match_flags0); + + extract_keys (msm->vnet_main, + sw_if_index1, + b1, + &port_sw_if_index1, + &first_ethertype1, + &outer_id1, + &inner_id1, + &match_flags1); + + eth_vlan_table_lookups (ðernet_main, + msm->vnet_main, + port_sw_if_index0, + first_ethertype0, + outer_id0, + inner_id0, + &hi0, + &main_intf0, + &vlan_intf0, + &qinq_intf0); + + eth_vlan_table_lookups (ðernet_main, + msm->vnet_main, + port_sw_if_index1, + first_ethertype1, + outer_id1, + inner_id1, + &hi1, + &main_intf1, + &vlan_intf1, + &qinq_intf1); + + matched0 = eth_identify_subint (hi0, + b0, + match_flags0, + main_intf0, + vlan_intf0, + qinq_intf0, + &subint_sw_if_index0, + &error0, + &is_l20); + + matched1 = eth_identify_subint (hi1, + b1, + match_flags1, + main_intf1, + vlan_intf1, + qinq_intf1, + &subint_sw_if_index1, + &error1, + &is_l21); + + if (PREDICT_FALSE (sw_if_index0 != subint_sw_if_index0)) { + // Drop packet + next0 = L2_EFP_FILTER_NEXT_DROP; + b0->error = node->errors[L2_EFP_FILTER_ERROR_DROP]; + } + + if (PREDICT_FALSE (sw_if_index1 != subint_sw_if_index1)) { + // Drop packet + next1 = L2_EFP_FILTER_NEXT_DROP; + b1->error = node->errors[L2_EFP_FILTER_ERROR_DROP]; + } + + if (PREDICT_FALSE((node->flags & VLIB_NODE_FLAG_TRACE))) { + if (b0->flags & VLIB_BUFFER_IS_TRACED) { + ethernet_header_t * h0 = vlib_buffer_get_current (b0); + l2_efp_filter_trace_t *t = + vlib_add_trace (vm, node, b0, sizeof (*t)); + t->sw_if_index = sw_if_index0; + memcpy(t->src, h0->src_address, 6); + memcpy(t->dst, h0->dst_address, 6); + memcpy(t->raw, &h0->type, sizeof(t->raw)); + } + if (b1->flags & VLIB_BUFFER_IS_TRACED) { + ethernet_header_t * h1 = vlib_buffer_get_current (b1); + l2_efp_filter_trace_t *t = + vlib_add_trace (vm, node, b1, sizeof (*t)); + t->sw_if_index = sw_if_index1; + memcpy(t->src, h1->src_address, 6); + memcpy(t->dst, h1->dst_address, 6); + memcpy(t->raw, &h1->type, sizeof(t->raw)); + } + } + + /* verify speculative enqueues, maybe switch current next frame */ + /* if next0==next1==next_index then nothing special needs to be done */ + 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; + u32 sw_if_index0; + u32 feature_bitmap0; + u16 first_ethertype0; + u16 outer_id0, inner_id0; + u32 match_flags0; + u32 port_sw_if_index0, subint_sw_if_index0; + vnet_hw_interface_t * hi0; + main_intf_t * main_intf0; + vlan_intf_t * vlan_intf0; + qinq_intf_t * qinq_intf0; + u32 is_l20; + __attribute__((unused)) u32 matched0; + u8 error0; + + /* 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_TX]; + + // process 1 packet + em->counters[node_counter_base_index + L2_EFP_FILTER_ERROR_L2_EFP_FILTER] += 1; + + // Remove ourself from the feature bitmap + feature_bitmap0 = vnet_buffer(b0)->l2.feature_bitmap & ~L2OUTPUT_FEAT_EFP_FILTER; + + // Determine next node + l2_output_dispatch (msm->vlib_main, + msm->vnet_main, + node, + l2_efp_filter_node.index, + &cached_sw_if_index, + &cached_next_index, + &msm->next_nodes, + b0, + sw_if_index0, + feature_bitmap0, + &next0); + + // perform the efp filter check on one packet + + extract_keys (msm->vnet_main, + sw_if_index0, + b0, + &port_sw_if_index0, + &first_ethertype0, + &outer_id0, + &inner_id0, + &match_flags0); + + eth_vlan_table_lookups (ðernet_main, + msm->vnet_main, + port_sw_if_index0, + first_ethertype0, + outer_id0, + inner_id0, + &hi0, + &main_intf0, + &vlan_intf0, + &qinq_intf0); + + matched0 = eth_identify_subint (hi0, + b0, + match_flags0, + main_intf0, + vlan_intf0, + qinq_intf0, + &subint_sw_if_index0, + &error0, + &is_l20); + + if (PREDICT_FALSE (sw_if_index0 != subint_sw_if_index0)) { + // Drop packet + next0 = L2_EFP_FILTER_NEXT_DROP; + b0->error = node->errors[L2_EFP_FILTER_ERROR_DROP]; + } + + if (PREDICT_FALSE((node->flags & VLIB_NODE_FLAG_TRACE) + && (b0->flags & VLIB_BUFFER_IS_TRACED))) { + ethernet_header_t * h0 = vlib_buffer_get_current (b0); + l2_efp_filter_trace_t *t = + vlib_add_trace (vm, node, b0, sizeof (*t)); + t->sw_if_index = sw_if_index0; + memcpy(t->src, h0->src_address, 6); + memcpy(t->dst, h0->dst_address, 6); + memcpy(t->raw, &h0->type, sizeof(t->raw)); + } + + /* 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; +} + + +VLIB_REGISTER_NODE (l2_efp_filter_node,static) = { + .function = l2_efp_filter_node_fn, + .name = "l2-efp-filter", + .vector_size = sizeof (u32), + .format_trace = format_l2_efp_filter_trace, + .type = VLIB_NODE_TYPE_INTERNAL, + + .n_errors = ARRAY_LEN(l2_efp_filter_error_strings), + .error_strings = l2_efp_filter_error_strings, + + .n_next_nodes = L2_EFP_FILTER_N_NEXT, + + /* edit / add dispositions here */ + .next_nodes = { + [L2_EFP_FILTER_NEXT_DROP] = "error-drop", + }, +}; + +clib_error_t *l2_efp_filter_init (vlib_main_t *vm) +{ + l2_efp_filter_main_t * mp = &l2_efp_filter_main; + + mp->vlib_main = vm; + mp->vnet_main = vnet_get_main(); + + // Initialize the feature next-node indexes + feat_bitmap_init_next_nodes(vm, + l2_efp_filter_node.index, + L2OUTPUT_N_FEAT, + l2output_get_feat_names(), + mp->next_nodes.feat_next_node_index); + + // Initialize the output node mapping table + l2output_init_output_node_vec(&mp->next_nodes.output_node_index_vec); + + return 0; +} + +VLIB_INIT_FUNCTION (l2_efp_filter_init); + + +// Enable/disable the EFP Filter check on the subinterface +void l2_efp_filter_configure (vnet_main_t * vnet_main, + u32 sw_if_index, + u32 enable) +{ + // set the interface flag + l2output_intf_bitmap_enable(sw_if_index, L2OUTPUT_FEAT_EFP_FILTER, enable); +} + + +// set subinterface egress efp filter enable/disable +// The CLI format is: +// set interface l2 efp-filter <interface> [disable]] +static clib_error_t * +int_l2_efp_filter (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; + } + + // enable/disable the feature + l2_efp_filter_configure (vnm, sw_if_index, enable); + + done: + return error; +} + + +VLIB_CLI_COMMAND (int_l2_efp_filter_cli, static) = { + .path = "set interface l2 efp-filter", + .short_help = "set interface l2 efp-filter <interface> [disable]", + .function = int_l2_efp_filter, +}; + |