/* * mpls_output.c: MPLS Adj rewrite * * Copyright (c) 2012-2014 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/ip/ip.h> #include <vnet/mpls/mpls.h> #include <vnet/ip/ip_frag.h> #include <vnet/adj/adj_dp.h> typedef struct { /* Adjacency taken. */ u32 adj_index; u32 flow_hash; } mpls_output_trace_t; typedef enum { MPLS_OUTPUT_MODE, MPLS_OUTPUT_MIDCHAIN_MODE }mpls_output_mode_t; #define foreach_mpls_output_next \ _(DROP, "error-drop") \ _(FRAG, "mpls-frag") typedef enum { #define _(s,n) MPLS_OUTPUT_NEXT_##s, foreach_mpls_output_next #undef _ MPLS_OUTPUT_N_NEXT, } mpls_output_next_t; static u8 * format_mpls_output_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 *); mpls_output_trace_t * t = va_arg (*args, mpls_output_trace_t *); s = format (s, "adj-idx %d : %U flow hash: 0x%08x", t->adj_index, format_ip_adjacency, t->adj_index, FORMAT_IP_ADJACENCY_NONE, t->flow_hash); return s; } static inline uword mpls_output_inline (vlib_main_t * vm, vlib_node_runtime_t * node, vlib_frame_t * from_frame, mpls_output_mode_t mode) { u32 n_left_from, next_index, * from, * to_next, thread_index; vlib_node_runtime_t * error_node; u32 n_left_to_next; mpls_main_t *mm; thread_index = vlib_get_thread_index(); error_node = vlib_node_get_runtime (vm, mpls_output_node.index); from = vlib_frame_vector_args (from_frame); n_left_from = from_frame->n_vectors; next_index = node->cached_next_index; mm = &mpls_main; while (n_left_from > 0) { vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next); while (n_left_from >= 4 && n_left_to_next >= 2) { ip_adjacency_t * adj0; mpls_unicast_header_t *hdr0; vlib_buffer_t * p0; u32 pi0, adj_index0, next0, error0; word rw_len0; ip_adjacency_t * adj1; mpls_unicast_header_t *hdr1; vlib_buffer_t * p1; u32 pi1, adj_index1, next1, error1; word rw_len1; /* 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, STORE); vlib_prefetch_buffer_header (p3, STORE); CLIB_PREFETCH (p2->data, sizeof (hdr0[0]), STORE); CLIB_PREFETCH (p3->data, sizeof (hdr1[0]), STORE); } pi0 = to_next[0] = from[0]; pi1 = to_next[1] = from[1]; from += 2; n_left_from -= 2; to_next += 2; n_left_to_next -= 2; p0 = vlib_get_buffer (vm, pi0); p1 = vlib_get_buffer (vm, pi1); adj_index0 = vnet_buffer (p0)->ip.adj_index[VLIB_TX]; adj_index1 = vnet_buffer (p1)->ip.adj_index[VLIB_TX]; adj0 = adj_get(adj_index0); adj1 = adj_get(adj_index1); hdr0 = vlib_buffer_get_current (p0); hdr1 = vlib_buffer_get_current (p1); /* Guess we are only writing on simple Ethernet header. */ vnet_rewrite_two_headers (adj0[0], adj1[0], hdr0, hdr1, sizeof (ethernet_header_t)); /* Update packet buffer attributes/set output interface. */ rw_len0 = adj0[0].rewrite_header.data_bytes; rw_len1 = adj1[0].rewrite_header.data_bytes; vnet_buffer (p0)->mpls.save_rewrite_length = rw_len0; vnet_buffer (p1)->mpls.save_rewrite_length = rw_len1; /* Bump the adj counters for packet and bytes */ vlib_increment_combined_counter (&adjacency_counters, thread_index, adj_index0, 1, vlib_buffer_length_in_chain (vm, p0) + rw_len0); vlib_increment_combined_counter (&adjacency_counters, thread_index, adj_index1, 1, vlib_buffer_length_in_chain (vm, p1) + rw_len1); /* Check MTU of outgoing interface. */ if (PREDICT_TRUE(vlib_buffer_length_in_chain (vm, p0) <= adj0[0].rewrite_header.max_l3_packet_bytes)) { vlib_buffer_advance(p0, -rw_len0); vnet_buffer (p0)->sw_if_index[VLIB_TX] = adj0[0].rewrite_header.sw_if_index; next0 = adj0[0].rewrite_header.next_index; error0 = IP4_ERROR_NONE; if (PREDICT_FALSE(adj0[0].rewrite_header.flags & VNET_REWRITE_HAS_FEATURES)) vnet_feature_arc_start (mm->output_feature_arc_index, adj0[0].rewrite_header.sw_if_index, &next0, p0); } else { error0 = IP4_ERROR_MTU_EXCEEDED; next0 = MPLS_OUTPUT_NEXT_FRAG; vlib_node_increment_counter (vm, mpls_output_node.index, MPLS_ERROR_PKTS_NEED_FRAG, 1); } if (PREDICT_TRUE(vlib_buffer_length_in_chain (vm, p1) <= adj1[0].rewrite_header.max_l3_packet_bytes)) { vlib_buffer_advance(p1, -rw_len1); vnet_buffer (p1)->sw_if_index[VLIB_TX] = adj1[0].rewrite_header.sw_if_index; next1 = adj1[0].rewrite_header.next_index; error1 = IP4_ERROR_NONE; if (PREDICT_FALSE(adj1[0].rewrite_header.flags & VNET_REWRITE_HAS_FEATURES)) vnet_feature_arc_start (mm->output_feature_arc_index, adj1[0].rewrite_header.sw_if_index, &next1, p1); } else { error1 = IP4_ERROR_MTU_EXCEEDED; next1 = MPLS_OUTPUT_NEXT_FRAG; vlib_node_increment_counter (vm, mpls_output_node.index, MPLS_ERROR_PKTS_NEED_FRAG, 1); } if (mode == MPLS_OUTPUT_MIDCHAIN_MODE) { adj_midchain_fixup (vm, adj0, p0, VNET_LINK_MPLS); adj_midchain_fixup (vm, adj1, p1, VNET_LINK_MPLS); } p0->error = error_node->errors[error0]; p1->error = error_node->errors[error1]; if (PREDICT_FALSE (p0->flags & VLIB_BUFFER_IS_TRACED)) { mpls_output_trace_t *tr = vlib_add_trace (vm, node, p0, sizeof (*tr)); tr->adj_index = vnet_buffer (p0)->ip.adj_index[VLIB_TX]; tr->flow_hash = vnet_buffer (p0)->ip.flow_hash; } if (PREDICT_FALSE (p1->flags & VLIB_BUFFER_IS_TRACED)) { mpls_output_trace_t *tr = vlib_add_trace (vm, node, p1, sizeof (*tr)); tr->adj_index = vnet_buffer (p1)->ip.adj_index[VLIB_TX]; tr->flow_hash = vnet_buffer (p1)->ip.flow_hash; } vlib_validate_buffer_enqueue_x2 (vm, node, next_index, to_next, n_left_to_next, pi0, pi1, next0, next1); } while (n_left_from > 0 && n_left_to_next > 0) { ip_adjacency_t * adj0; mpls_unicast_header_t *hdr0; vlib_buffer_t * p0; u32 pi0, adj_index0, next0, error0; word rw_len0; pi0 = to_next[0] = from[0]; p0 = vlib_get_buffer (vm, pi0); adj_index0 = vnet_buffer (p0)->ip.adj_index[VLIB_TX]; adj0 = adj_get(adj_index0); hdr0 = vlib_buffer_get_current (p0); /* Guess we are only writing on simple Ethernet header. */ vnet_rewrite_one_header (adj0[0], hdr0, sizeof (ethernet_header_t)); /* Update packet buffer attributes/set output interface. */ rw_len0 = adj0[0].rewrite_header.data_bytes; vnet_buffer (p0)->mpls.save_rewrite_length = rw_len0; vlib_increment_combined_counter (&adjacency_counters, thread_index, adj_index0, 1, vlib_buffer_length_in_chain (vm, p0) + rw_len0); /* Check MTU of outgoing interface. */ if (PREDICT_TRUE(vlib_buffer_length_in_chain (vm, p0) <= adj0[0].rewrite_header.max_l3_packet_bytes)) { vlib_buffer_advance(p0, -rw_len0); vnet_buffer (p0)->sw_if_index[VLIB_TX] = adj0[0].rewrite_header.sw_if_index; next0 = adj0[0].rewrite_header.next_index; error0 = IP4_ERROR_NONE; if (PREDICT_FALSE(adj0[0].rewrite_header.flags & VNET_REWRITE_HAS_FEATURES)) vnet_feature_arc_start (mm->output_feature_arc_index, adj0[0].rewrite_header.sw_if_index, &next0, p0); } else { error0 = IP4_ERROR_MTU_EXCEEDED; next0 = MPLS_OUTPUT_NEXT_FRAG; vlib_node_increment_counter (vm, mpls_output_node.index, MPLS_ERROR_PKTS_NEED_FRAG, 1); } if (mode == MPLS_OUTPUT_MIDCHAIN_MODE) { adj_midchain_fixup (vm, adj0, p0, VNET_LINK_MPLS); } p0->error = error_node->errors[error0]; from += 1; n_left_from -= 1; to_next += 1; n_left_to_next -= 1; if (PREDICT_FALSE(p0->flags & VLIB_BUFFER_IS_TRACED)) { mpls_output_trace_t *tr = vlib_add_trace (vm, node, p0, sizeof (*tr)); tr->adj_index = vnet_buffer(p0)->ip.adj_index[VLIB_TX]; tr->flow_hash = vnet_buffer(p0)->ip.flow_hash; } vlib_validate_buffer_enqueue_x1 (vm, node, next_index, to_next, n_left_to_next, pi0, next0); } vlib_put_next_frame (vm, node, next_index, n_left_to_next); } vlib_node_increment_counter (vm, mpls_output_node.index, MPLS_ERROR_PKTS_ENCAP, from_frame->n_vectors); return from_frame->n_vectors; } static char * mpls_error_strings[] = { #define mpls_error(n,s) s, #include "error.def" #undef mpls_error }; VLIB_NODE_FN (mpls_output_node) (vlib_main_t * vm, vlib_node_runtime_t * node, vlib_frame_t * from_frame) { return (mpls_output_inline(vm, node, from_frame, MPLS_OUTPUT_MODE)); } VLIB_REGISTER_NODE (mpls_output_node) = { .name = "mpls-output", /* Takes a vector of packets. */ .vector_size = sizeof (u32), .n_errors = MPLS_N_ERROR, .error_strings = mpls_error_strings, .n_next_nodes = MPLS_OUTPUT_N_NEXT, .next_nodes = { [MPLS_OUTPUT_NEXT_DROP] = "mpls-drop", [MPLS_OUTPUT_NEXT_FRAG] = "mpls-frag", }, .format_trace = format_mpls_output_trace, }; VLIB_NODE_FN (mpls_midchain_node) (vlib_main_t * vm, vlib_node_runtime_t * node, vlib_frame_t * from_frame) { return (mpls_output_inline(vm, node, from_frame, MPLS_OUTPUT_MIDCHAIN_MODE)); } VLIB_REGISTER_NODE (mpls_midchain_node) = { .name = "mpls-midchain", .vector_size = sizeof (u32), .n_errors = MPLS_N_ERROR, .error_strings = mpls_error_strings, .sibling_of = "mpls-output", .format_trace = format_mpls_output_trace, }; static char *mpls_frag_error_strings[] = { #define _(sym,string) string, foreach_ip_frag_error #undef _ }; typedef struct mpls_frag_trace_t_ { u16 pkt_size; u16 mtu; } mpls_frag_trace_t; typedef enum { MPLS_FRAG_NEXT_REWRITE, MPLS_FRAG_NEXT_REWRITE_MIDCHAIN, MPLS_FRAG_NEXT_ICMP4_ERROR, MPLS_FRAG_NEXT_ICMP6_ERROR, MPLS_FRAG_NEXT_DROP, MPLS_FRAG_N_NEXT, } mpls_frag_next_t; static uword mpls_frag (vlib_main_t * vm, vlib_node_runtime_t * node, vlib_frame_t * frame) { u32 n_left_from, next_index, * from, * to_next, n_left_to_next, *frags; from = vlib_frame_vector_args (frame); n_left_from = frame->n_vectors; next_index = node->cached_next_index; frags = NULL; while (n_left_from > 0) { vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next); while (n_left_from > 0 && n_left_to_next > 0) { ip_adjacency_t * adj0; vlib_buffer_t * p0; mpls_frag_next_t next0; u32 pi0, adj_index0; ip_frag_error_t error0 = IP_FRAG_ERROR_NONE; i16 encap_size, mtu; u8 is_ip4; pi0 = to_next[0] = from[0]; p0 = vlib_get_buffer (vm, pi0); from += 1; n_left_from -= 1; is_ip4 = vnet_buffer (p0)->mpls.pyld_proto == DPO_PROTO_IP4; adj_index0 = vnet_buffer (p0)->ip.adj_index[VLIB_TX]; adj0 = adj_get (adj_index0); /* the size of the MPLS stack */ encap_size = vnet_buffer (p0)->l3_hdr_offset - p0->current_data; mtu = adj0->rewrite_header.max_l3_packet_bytes - encap_size; /* IP fragmentation */ if (is_ip4) error0 = ip4_frag_do_fragment (vm, pi0, mtu, encap_size, &frags); else { if (!(p0->flags & VNET_BUFFER_F_LOCALLY_ORIGINATED)) { /* only fragment locally generated IPv6 */ error0 = IP_FRAG_ERROR_DONT_FRAGMENT_SET; } else { error0 = ip6_frag_do_fragment (vm, pi0, mtu, encap_size, &frags); } } if (PREDICT_FALSE (p0->flags & VLIB_BUFFER_IS_TRACED)) { mpls_frag_trace_t *tr = vlib_add_trace (vm, node, p0, sizeof (*tr)); tr->mtu = mtu; tr->pkt_size = vlib_buffer_length_in_chain (vm, p0); } if (PREDICT_TRUE (error0 == IP_FRAG_ERROR_NONE)) { /* Free original buffer chain */ vlib_buffer_free_one (vm, pi0); next0 = (IP_LOOKUP_NEXT_MIDCHAIN == adj0->lookup_next_index ? MPLS_FRAG_NEXT_REWRITE_MIDCHAIN : MPLS_FRAG_NEXT_REWRITE); } else { vlib_error_count (vm, node->node_index, error0, 1); if (error0 == IP_FRAG_ERROR_DONT_FRAGMENT_SET) { vlib_buffer_advance (p0, encap_size); if (is_ip4) { icmp4_error_set_vnet_buffer ( p0, ICMP4_destination_unreachable, ICMP4_destination_unreachable_fragmentation_needed_and_dont_fragment_set, mtu); next0 = MPLS_FRAG_NEXT_ICMP4_ERROR; } else { icmp6_error_set_vnet_buffer (p0, ICMP6_packet_too_big, 0, mtu); next0 = MPLS_FRAG_NEXT_ICMP6_ERROR; } } else { next0 = MPLS_FRAG_NEXT_DROP; } /* Get rid of the original buffer */ vec_add1 (frags, pi0); } /* Send fragments that were added in the frame */ u32 *frag_from, frag_left; frag_from = frags; frag_left = vec_len (frags); while (frag_left > 0) { while (frag_left > 0 && n_left_to_next > 0) { u32 i; i = to_next[0] = frag_from[0]; frag_from += 1; frag_left -= 1; to_next += 1; n_left_to_next -= 1; vlib_validate_buffer_enqueue_x1 ( vm, node, next_index, to_next, n_left_to_next, i, next0); } vlib_put_next_frame (vm, node, next_index, n_left_to_next); vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next); } vec_reset_length (frags); } vlib_put_next_frame (vm, node, next_index, n_left_to_next); } vec_free (frags); return frame->n_vectors; } static u8 * format_mpls_frag_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 *); mpls_frag_trace_t *t = va_arg (*args, mpls_frag_trace_t *); s = format (s, "mtu:%d pkt-size:%d", t->mtu, t->pkt_size); return s; } VLIB_REGISTER_NODE (mpls_frag_node) = { .function = mpls_frag, .name = "mpls-frag", .vector_size = sizeof (u32), .format_trace = format_mpls_frag_trace, .type = VLIB_NODE_TYPE_INTERNAL, .n_errors = IP_FRAG_N_ERROR, .error_strings = mpls_frag_error_strings, .n_next_nodes = MPLS_FRAG_N_NEXT, .next_nodes = { [MPLS_FRAG_NEXT_REWRITE] = "mpls-output", [MPLS_FRAG_NEXT_REWRITE_MIDCHAIN] = "mpls-midchain", [MPLS_FRAG_NEXT_ICMP4_ERROR] = "ip4-icmp-error", [MPLS_FRAG_NEXT_ICMP6_ERROR] = "ip6-icmp-error", [MPLS_FRAG_NEXT_DROP] = "mpls-drop" }, }; /* * @brief Next index values from the MPLS incomplete adj node */ #define foreach_mpls_adj_incomplete_next \ _(DROP, "error-drop") \ _(IP4, "ip4-arp") \ _(IP6, "ip6-discover-neighbor") typedef enum { #define _(s,n) MPLS_ADJ_INCOMPLETE_NEXT_##s, foreach_mpls_adj_incomplete_next #undef _ MPLS_ADJ_INCOMPLETE_N_NEXT, } mpls_adj_incomplete_next_t; /** * @brief A struct to hold tracing information for the MPLS label imposition * node. */ typedef struct mpls_adj_incomplete_trace_t_ { u32 next; } mpls_adj_incomplete_trace_t; /** * @brief Graph node for incomplete MPLS adjacency. * This node will push traffic to either the v4-arp or v6-nd node * based on the next-hop proto of the adj. * We pay a cost for this 'routing' node, but an incomplete adj is the * exception case. */ VLIB_NODE_FN (mpls_adj_incomplete_node) (vlib_main_t * vm, vlib_node_runtime_t * node, vlib_frame_t * from_frame) { u32 n_left_from, next_index, * from, * to_next; from = vlib_frame_vector_args (from_frame); n_left_from = 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 > 0 && n_left_to_next > 0) { u32 pi0, next0, adj_index0; ip_adjacency_t * adj0; vlib_buffer_t * p0; pi0 = to_next[0] = from[0]; p0 = vlib_get_buffer (vm, pi0); from += 1; n_left_from -= 1; to_next += 1; n_left_to_next -= 1; adj_index0 = vnet_buffer (p0)->ip.adj_index[VLIB_TX]; adj0 = adj_get(adj_index0); if (PREDICT_TRUE(FIB_PROTOCOL_IP4 == adj0->ia_nh_proto)) { next0 = MPLS_ADJ_INCOMPLETE_NEXT_IP4; } else { next0 = MPLS_ADJ_INCOMPLETE_NEXT_IP6; } if (PREDICT_FALSE(p0->flags & VLIB_BUFFER_IS_TRACED)) { mpls_adj_incomplete_trace_t *tr = vlib_add_trace (vm, node, p0, sizeof (*tr)); tr->next = next0; } vlib_validate_buffer_enqueue_x1 (vm, node, next_index, to_next, n_left_to_next, pi0, next0); } vlib_put_next_frame (vm, node, next_index, n_left_to_next); } return from_frame->n_vectors; } static u8 * format_mpls_adj_incomplete_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 *); mpls_adj_incomplete_trace_t * t; u32 indent; t = va_arg (*args, mpls_adj_incomplete_trace_t *); indent = format_get_indent (s); s = format (s, "%Unext:%d", format_white_space, indent, t->next); return (s); } VLIB_REGISTER_NODE (mpls_adj_incomplete_node) = { .name = "mpls-adj-incomplete", .format_trace = format_mpls_adj_incomplete_trace, /* Takes a vector of packets. */ .vector_size = sizeof (u32), .n_errors = MPLS_N_ERROR, .error_strings = mpls_error_strings, .n_next_nodes = MPLS_ADJ_INCOMPLETE_N_NEXT, .next_nodes = { #define _(s,n) [MPLS_ADJ_INCOMPLETE_NEXT_##s] = n, foreach_mpls_adj_incomplete_next #undef _ }, };