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diff --git a/src/vnet/l2/l2_efp_filter.c b/src/vnet/l2/l2_efp_filter.c
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+++ b/src/vnet/l2/l2_efp_filter.c
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+/*
+ * 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>
+
+/**
+ * @file
+ * @brief EFP-filter - Ethernet Flow Point Filter.
+ *
+ * It is possible to transmit a packet out a subinterface with VLAN tags
+ * that are not compatible with that subinterface. In other words, if that
+ * packet arrived on the output port, it would not be classified as coming
+ * from the output subinterface. This can happen in various ways: through
+ * misconfiguration, by putting subinterfaces with different VLAN encaps in
+ * the same bridge-domain, etc. The EFP Filter Check detects such packets
+ * and drops them. It consists of two checks, one that verifies the packet
+ * prior to output VLAN tag rewrite and one that verifies the packet after
+ * VLAN tag rewrite.
+ *
+ */
+typedef struct
+{
+ /* Next nodes for L2 output features */
+ u32 l2_out_feat_next[32];
+
+ /* 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;
+
+ 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;
+ 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);
+ * 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;
+
+ /* Determine next node */
+ next0 = vnet_l2_feature_next (b0, msm->l2_out_feat_next,
+ L2OUTPUT_FEAT_EFP_FILTER);
+ next1 = vnet_l2_feature_next (b1, msm->l2_out_feat_next,
+ L2OUTPUT_FEAT_EFP_FILTER);
+
+ /* 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 (&ethernet_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 (&ethernet_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;
+ clib_memcpy (t->src, h0->src_address, 6);
+ clib_memcpy (t->dst, h0->dst_address, 6);
+ clib_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;
+ clib_memcpy (t->src, h1->src_address, 6);
+ clib_memcpy (t->dst, h1->dst_address, 6);
+ clib_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;
+ 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;
+
+ /* Determine next node */
+ next0 = vnet_l2_feature_next (b0, msm->l2_out_feat_next,
+ L2OUTPUT_FEAT_EFP_FILTER);
+
+ /* 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 (&ethernet_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;
+ clib_memcpy (t->src, h0->src_address, 6);
+ clib_memcpy (t->dst, h0->dst_address, 6);
+ clib_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;
+}
+
+
+/* *INDENT-OFF* */
+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",
+ },
+};
+/* *INDENT-ON* */
+
+VLIB_NODE_FUNCTION_MULTIARCH (l2_efp_filter_node, l2_efp_filter_node_fn)
+ 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->l2_out_feat_next);
+
+ 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;
+}
+
+
+/*?
+ * 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. This command enables or disables the EFP filtering
+ * for a given sub-interface.
+ *
+ * @cliexpar
+ * Example of how to enable a Layer 2 efp-filter on a sub-interface:
+ * @cliexcmd{set interface l2 efp-filter GigabitEthernet0/8/0.200}
+ * Example of how to disable a Layer 2 efp-filter on a sub-interface:
+ * @cliexcmd{set interface l2 efp-filter GigabitEthernet0/8/0.200 disable}
+?*/
+/* *INDENT-OFF* */
+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,
+};
+/* *INDENT-ON* */
+
+
+/*
+ * fd.io coding-style-patch-verification: ON
+ *
+ * Local Variables:
+ * eval: (c-set-style "gnu")
+ * End:
+ */