/* * 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. */ #include <vnet/mpls/mpls.h> #include <vnet/dpo/mpls_label_dpo.h> #include <vnet/dpo/load_balance.h> #include <vnet/dpo/drop_dpo.h> #include <vnet/fib/fib_path_ext.h> #include <vnet/fib/fib_entry_src.h> #include <vnet/fib/fib_path.h> #include <vnet/fib/fib_path_list.h> #include <vnet/fib/fib_internal.h> const char *fib_path_ext_adj_flags_names[] = FIB_PATH_EXT_ADJ_ATTR_NAMES; u8 * format_fib_path_ext (u8 * s, va_list * args) { fib_path_ext_t *path_ext; u32 ii; path_ext = va_arg (*args, fib_path_ext_t *); s = format(s, "path:%d ", path_ext->fpe_path_index); switch (path_ext->fpe_type) { case FIB_PATH_EXT_MPLS: s = format(s, "labels:", path_ext->fpe_path_index); for (ii = 0; ii < vec_len(path_ext->fpe_path.frp_label_stack); ii++) { s = format(s, "%U ", format_mpls_unicast_label, path_ext->fpe_path.frp_label_stack[ii]); } break; case FIB_PATH_EXT_ADJ: { fib_path_ext_adj_attr_t attr; s = format(s, "adj-flags:"); if (path_ext->fpe_adj_flags) { FOR_EACH_PATH_EXT_ADJ_ATTR(attr) { s = format(s, "%s", fib_path_ext_adj_flags_names[attr]); } } else { s = format(s, "None"); } break; } } return (s); } int fib_path_ext_cmp (fib_path_ext_t *path_ext, const fib_route_path_t *rpath) { return (fib_route_path_cmp(&path_ext->fpe_path, rpath)); } static fib_path_list_walk_rc_t fib_path_ext_match (fib_node_index_t pl_index, fib_node_index_t path_index, void *ctx) { fib_path_ext_t *path_ext = ctx; if (!fib_path_cmp_w_route_path(path_index, &path_ext->fpe_path)) { path_ext->fpe_path_index = path_index; return (FIB_PATH_LIST_WALK_STOP); } return (FIB_PATH_LIST_WALK_CONTINUE); } void fib_path_ext_resolve (fib_path_ext_t *path_ext, fib_node_index_t path_list_index) { /* * Find the path on the path list that this is an extension for */ path_ext->fpe_path_index = FIB_NODE_INDEX_INVALID; fib_path_list_walk(path_list_index, fib_path_ext_match, path_ext); } static void fib_path_ext_init (fib_path_ext_t *path_ext, fib_node_index_t path_list_index, fib_path_ext_type_t ext_type, const fib_route_path_t *rpath) { path_ext->fpe_path = *rpath; path_ext->fpe_path_index = FIB_NODE_INDEX_INVALID; path_ext->fpe_adj_flags = FIB_PATH_EXT_ADJ_FLAG_NONE; path_ext->fpe_type = ext_type; fib_path_ext_resolve(path_ext, path_list_index); } /** * @brief Return true if the label stack is implicit null */ static int fib_path_ext_is_imp_null (fib_path_ext_t *path_ext) { return ((1 == vec_len(path_ext->fpe_label_stack)) && (MPLS_IETF_IMPLICIT_NULL_LABEL == path_ext->fpe_label_stack[0])); } load_balance_path_t * fib_path_ext_stack (fib_path_ext_t *path_ext, fib_forward_chain_type_t child_fct, fib_forward_chain_type_t imp_null_fct, load_balance_path_t *nhs) { fib_forward_chain_type_t parent_fct; load_balance_path_t *nh; if (!fib_path_is_resolved(path_ext->fpe_path_index)) return (nhs); /* * Since we are stacking this path-extension, it must have a valid out * label. From the chain type request by the child, determine what * chain type we will request from the parent. */ switch (child_fct) { case FIB_FORW_CHAIN_TYPE_MPLS_EOS: { /* * The EOS chain is a tricky since, when the path has an imp NULL one cannot know * the adjacency to link to without knowing what the packets payload protocol * will be once the label is popped. */ if (fib_path_ext_is_imp_null(path_ext)) { parent_fct = imp_null_fct; } else { /* * we have a label to stack. packets will thus be labelled when * they encounter the child, ergo, non-eos. */ parent_fct = FIB_FORW_CHAIN_TYPE_MPLS_NON_EOS; } break; } case FIB_FORW_CHAIN_TYPE_UNICAST_IP4: case FIB_FORW_CHAIN_TYPE_UNICAST_IP6: if (fib_path_ext_is_imp_null(path_ext)) { /* * implicit-null label for the eos or IP chain, need to pick up * the IP adj */ parent_fct = child_fct; } else { /* * we have a label to stack. packets will thus be labelled when * they encounter the child, ergo, non-eos. */ parent_fct = FIB_FORW_CHAIN_TYPE_MPLS_NON_EOS; } break; case FIB_FORW_CHAIN_TYPE_MPLS_NON_EOS: parent_fct = child_fct; break; case FIB_FORW_CHAIN_TYPE_ETHERNET: parent_fct = FIB_FORW_CHAIN_TYPE_MPLS_NON_EOS; break; default: return (nhs); break; } dpo_id_t via_dpo = DPO_INVALID; /* * The next object in the graph after the imposition of the label * will be the DPO contributed by the path through which the packets * are to be sent. We stack the MPLS Label DPO on this path DPO */ fib_path_contribute_forwarding(path_ext->fpe_path_index, parent_fct, &via_dpo); if (dpo_is_drop(&via_dpo) || load_balance_is_drop(&via_dpo)) { /* * don't stack a path extension on a drop. doing so will create * a LB bucket entry on drop, and we will lose a percentage of traffic. */ } else { vec_add2(nhs, nh, 1); nh->path_weight = fib_path_get_weight(path_ext->fpe_path_index); nh->path_index = path_ext->fpe_path_index; dpo_copy(&nh->path_dpo, &via_dpo); /* * The label is stackable for this chain type * construct the mpls header that will be imposed in the data-path */ if (!fib_path_ext_is_imp_null(path_ext)) { /* * we use the parent protocol for the label so that * we pickup the correct MPLS imposition nodes to do * ip[46] processing. */ dpo_proto_t chain_proto; mpls_eos_bit_t eos; index_t mldi; eos = (child_fct == FIB_FORW_CHAIN_TYPE_MPLS_NON_EOS ? MPLS_NON_EOS : MPLS_EOS); chain_proto = fib_forw_chain_type_to_dpo_proto(child_fct); mldi = mpls_label_dpo_create(path_ext->fpe_label_stack, eos, 255, 0, chain_proto, &nh->path_dpo); dpo_set(&nh->path_dpo, DPO_MPLS_LABEL, chain_proto, mldi); } } dpo_reset(&via_dpo); return (nhs); } fib_path_ext_t * fib_path_ext_list_find (const fib_path_ext_list_t *list, fib_path_ext_type_t ext_type, const fib_route_path_t *rpath) { fib_path_ext_t *path_ext; vec_foreach(path_ext, list->fpel_exts) { if ((path_ext->fpe_type == ext_type) && !fib_path_ext_cmp(path_ext, rpath) ) { return (path_ext); } } return (NULL); } fib_path_ext_t * fib_path_ext_list_find_by_path_index (const fib_path_ext_list_t *list, fib_node_index_t path_index) { fib_path_ext_t *path_ext; vec_foreach(path_ext, list->fpel_exts) { if (path_ext->fpe_path_index == path_index) { return (path_ext); } } return (NULL); } fib_path_ext_t * fib_path_ext_list_push_back (fib_path_ext_list_t *list, fib_node_index_t path_list_index, fib_path_ext_type_t ext_type, const fib_route_path_t *rpath) { fib_path_ext_t *path_ext; path_ext = fib_path_ext_list_find(list, ext_type, rpath); if (NULL == path_ext) { vec_add2(list->fpel_exts, path_ext, 1); fib_path_ext_init(path_ext, path_list_index, ext_type, rpath); } return (path_ext); } /* * insert, sorted, a path extension to the entry's list. * It's not strictly necessary to sort the path extensions, since each * extension has the path index to which it resolves. However, by being * sorted the load-balance produced has a deterministic order, not an order * based on the sequence of extension additions. this is a considerable benefit. */ fib_path_ext_t * fib_path_ext_list_insert (fib_path_ext_list_t *list, fib_node_index_t path_list_index, fib_path_ext_type_t ext_type, const fib_route_path_t *rpath) { fib_path_ext_t new_path_ext, *path_ext; int i = 0; if (0 == fib_path_ext_list_length(list)) { return (fib_path_ext_list_push_back(list, path_list_index, ext_type, rpath)); } fib_path_ext_init(&new_path_ext, path_list_index, ext_type, rpath); vec_foreach(path_ext, list->fpel_exts) { int res = fib_path_ext_cmp(path_ext, rpath); if (0 == res) { /* * don't add duplicate extensions. modify instead */ vec_free(path_ext->fpe_label_stack); *path_ext = new_path_ext; goto done; } else if (res < 0) { i++; } else { break; } } vec_insert_elts(list->fpel_exts, &new_path_ext, 1, i); done: return (&(list->fpel_exts[i])); } void fib_path_ext_list_resolve (fib_path_ext_list_t *list, fib_node_index_t path_list_index) { fib_path_ext_t *path_ext; vec_foreach(path_ext, list->fpel_exts) { fib_path_ext_resolve(path_ext, path_list_index); }; } void fib_path_ext_list_remove (fib_path_ext_list_t *list, fib_path_ext_type_t ext_type, const fib_route_path_t *rpath) { fib_path_ext_t *path_ext; path_ext = fib_path_ext_list_find(list, ext_type, rpath); if (NULL != path_ext) { /* * delete the element moving the remaining elements down 1 position. * this preserves the sorted order. */ vec_free(path_ext->fpe_label_stack); vec_delete(list->fpel_exts, 1, (path_ext - list->fpel_exts)); } } void fib_path_ext_list_flush (fib_path_ext_list_t *list) { fib_path_ext_t *path_ext; vec_foreach(path_ext, list->fpel_exts) { vec_free(path_ext->fpe_label_stack); }; vec_free(list->fpel_exts); list->fpel_exts = NULL; } u8* format_fib_path_ext_list (u8 * s, va_list * args) { fib_path_ext_list_t *list; fib_path_ext_t *path_ext; list = va_arg (*args, fib_path_ext_list_t *); if (fib_path_ext_list_length(list)) { s = format(s, " Extensions:"); vec_foreach(path_ext, list->fpel_exts) { s = format(s, "\n %U", format_fib_path_ext, path_ext); }; } return (s); } int fib_path_ext_list_length (const fib_path_ext_list_t *list) { return (vec_len(list->fpel_exts)); }