/* * BIRD Internet Routing Daemon -- Route aggregation * * (c) 2023--2023 Igor Putovny * (c) 2023 CZ.NIC, z.s.p.o. * * Can be freely distributed and used under the terms of the GNU GPL. */ /** * DOC: Route aggregation * * This is an implementation of route aggregation functionality. * It enables user to specify a set of route attributes in the configuarion file * and then, for a given destination (net), aggregate routes with the same * values of these attributes into a single multi-path route. * * Structure &channel contains pointer to aggregation list which is represented * by &aggr_list_linearized. In rt_notify_aggregated(), attributes from this * list are evaluated for every route of a given net and results are stored * in &rte_val_list which contains pointer to this route and array of &f_val. * Array of pointers to &rte_val_list entries is sorted using * sort_rte_val_list(). For comparison of &f_val structures, val_compare() * is used. Comparator function is written so that sorting is stable. If all * attributes have the same values, routes are compared by their global IDs. * * After sorting, &rte_val_list entries containing equivalent routes will be * adjacent to each other. Function process_rte_list() iterates through these * entries to identify sequences of equivalent routes. New route will be * created for each such sequence, even if only from a single route. * Only attributes from the aggreagation list will be set for the new route. * New &rta is created and prepare_rta() is used to copy static and dynamic * attributes to new &rta from &rta of the original route. New route is created * by create_merged_rte() from new &rta and exported to the routing table. */ #undef LOCAL_DEBUG #ifndef _GNU_SOURCE #define _GNU_SOURCE #endif #include "nest/bird.h" #include "nest/iface.h" #include "filter/filter.h" #include "proto/aggregator/aggregator.h" #include #include /* #include "nest/route.h" #include "nest/iface.h" #include "lib/resource.h" #include "lib/event.h" #include "lib/timer.h" #include "lib/string.h" #include "conf/conf.h" #include "filter/filter.h" #include "filter/data.h" #include "lib/hash.h" #include "lib/string.h" #include "lib/alloca.h" #include "lib/flowspec.h" */ extern linpool *rte_update_pool; static void aggregator_bucket_update(struct aggregator_proto *p, struct aggregator_bucket *bucket, struct network *net); static inline int is_leaf(const struct trie_node *node) { assert(node != NULL); return !node->child[0] && !node->child[1]; } /* * Allocate new node in protocol slab */ static struct trie_node * new_node(slab *trie_slab) { struct trie_node *new = sl_alloc(trie_slab); assert(new != NULL); *new = (struct trie_node) { 0 }; assert(new->bucket == NULL); return new; } /* * Mark appropriate child of parent node as NULL and free @node */ static void remove_node(struct trie_node *node) { assert(node != NULL); assert(node->child[0] == NULL && node->child[1] == NULL); if (node->parent == NULL) goto free_node; if (node->parent->child[0] == node) node->parent->child[0] = NULL; else if (node->parent->child[1] == node) node->parent->child[1] = NULL; else bug("Invalid child pointer"); free_node: sl_free(node); } /* * Recursively free all trie nodes */ static void delete_trie(struct trie_node *node) { assert(node != NULL); if (node->child[0]) delete_trie(node->child[0]); if (node->child[1]) delete_trie(node->child[1]); assert(is_leaf(node)); remove_node(node); } /* * Insert prefix in @addr to prefix trie with beginning at @root and assign @bucket to this prefix */ static void trie_insert_prefix_ip4(const struct net_addr_ip4 *addr, struct trie_node *const root, struct aggregator_bucket *bucket, slab *trie_slab) { assert(addr != NULL); assert(bucket != NULL); assert(root != NULL); assert(trie_slab != NULL); struct trie_node *node = root; for (u32 i = 0; i < addr->pxlen; i++) { u32 bit = ip4_getbit(addr->prefix, i); if (!node->child[bit]) { struct trie_node *new = new_node(trie_slab); new->parent = node; node->child[bit] = new; new->depth = new->parent->depth + 1; } node = node->child[bit]; } /* Assign bucket to the last node */ node->bucket = bucket; } static void trie_insert_prefix_ip6(const struct net_addr_ip6 *addr, struct trie_node * const root, struct aggregator_bucket *bucket, slab *trie_slab) { assert(addr != NULL); assert(bucket != NULL); assert(root != NULL); assert(trie_slab != NULL); struct trie_node *node = root; for (u32 i = 0; i < addr->pxlen; i++) { u32 bit = ip6_getbit(addr->prefix, i); if (!node->child[bit]) { struct trie_node *new = new_node(trie_slab); new->parent = node; node->child[bit] = new; new->depth = new->parent->depth + 1; } node = node->child[bit]; } /* Assign bucket to the last node */ node->bucket = bucket; } /* * Return first non-null bucket of the closest ancestor of @node */ static struct aggregator_bucket * get_ancestor_bucket(const struct trie_node *node) { /* Defined for other than root nodes */ while (1) { if (node->parent == NULL) return node->bucket; if (node->parent->bucket != NULL) return node->parent->bucket; node = node->parent; } } static void first_pass_new(struct trie_node *node, slab *trie_slab) { assert(node != NULL); assert(trie_slab != NULL); if (is_leaf(node)) { assert(node->bucket != NULL); assert(node->potential_buckets_count == 0); node->potential_buckets[node->potential_buckets_count++] = node->bucket; return; } if (node->bucket == NULL) node->bucket = node->parent->bucket; for (int i = 0; i < 2; i++) { if (!node->child[i]) { struct trie_node *new = new_node(trie_slab); new->parent = node; new->bucket = node->bucket; new->depth = node->depth + 1; node->child[i] = new; } } if (node->child[0]) first_pass_new(node->child[0], trie_slab); if (node->child[1]) first_pass_new(node->child[1], trie_slab); node->bucket = NULL; } static void first_pass_after_check_helper(const struct trie_node *node) { for (int i = 0; i < node->potential_buckets_count; i++) { for (int j = i + 1; j < node->potential_buckets_count; j++) { assert(node->potential_buckets[i] != node->potential_buckets[j]); } } } static void first_pass_after_check(const struct trie_node *node) { first_pass_after_check_helper(node); if (node->child[0]) { first_pass_after_check_helper(node->child[0]); } if (node->child[1]) { first_pass_after_check_helper(node->child[1]); } } /* * First pass of Optimal Route Table Construction (ORTC) algorithm */ static void first_pass(struct trie_node *node, slab *trie_slab) { assert(node != NULL); assert(trie_slab != NULL); if (node->parent == NULL) assert(node->bucket != NULL); if (is_leaf(node)) { /* for (int i = 0; i < node->potential_buckets_count; i++) { if (node->potential_buckets[i] == node->bucket) return; } */ assert(node->bucket != NULL); node->potential_buckets[node->potential_buckets_count++] = node->bucket; return; } /* Add leave nodes so that each node has either two or no children */ for (int i = 0; i < 2; i++) { if (!node->child[i]) { struct trie_node *new = new_node(trie_slab); new->parent = node; new->bucket = get_ancestor_bucket(new); node->child[i] = new; new->depth = new->parent->depth + 1; } } /* Preorder traversal */ first_pass(node->child[0], trie_slab); first_pass(node->child[1], trie_slab); } static int aggregator_bucket_compare(const struct aggregator_bucket *a, const struct aggregator_bucket *b) { assert(a != NULL); assert(b != NULL); if ((uintptr_t)a < (uintptr_t)b) return -1; if ((uintptr_t)a > (uintptr_t)b) return 1; return 0; } static int aggregator_bucket_compare_wrapper(const void *a, const void *b) { assert(a != NULL); assert(b != NULL); const struct aggregator_bucket *fst = *(struct aggregator_bucket **)a; const struct aggregator_bucket *snd = *(struct aggregator_bucket **)b; return aggregator_bucket_compare(fst, snd); } /* * Compute union of two sets of potential buckets in @left and @right and put result in @node */ static void unionize_buckets(const struct trie_node *left, const struct trie_node *right, struct trie_node *node) { assert(left != NULL); assert(right != NULL); assert(node != NULL); struct aggregator_bucket *input_buckets[64] = { 0 }; int input_count = 0; for (int i = 0; i < left->potential_buckets_count; i++) input_buckets[input_count++] = left->potential_buckets[i]; for (int i = 0; i < right->potential_buckets_count; i++) input_buckets[input_count++] = right->potential_buckets[i]; qsort(input_buckets, input_count, sizeof(struct aggregator_bucket *), aggregator_bucket_compare_wrapper); struct aggregator_bucket *output_buckets[64] = { 0 }; int output_count = 0; for (int i = 0; i < input_count; i++) { if (output_count != 0 && output_buckets[output_count - 1] == input_buckets[i]) continue; output_buckets[output_count++] = input_buckets[i]; } // strictly greater for (int i = 1; i < output_count; i++) assert(output_buckets[i - 1] < output_buckets[i]); // duplicates for (int i = 0; i < output_count; i++) for (int j = i + 1; j < output_count; j++) assert(output_buckets[i] != output_buckets[j]); for (int i = 0; i < output_count; i++) { if (node->potential_buckets_count >= MAX_POTENTIAL_BUCKETS_COUNT) break; node->potential_buckets[node->potential_buckets_count++] = output_buckets[i]; } } /* * Compute intersection of two sets of potential buckets in @left and @right and put result in @node */ static void intersect_buckets(const struct trie_node *left, const struct trie_node *right, struct trie_node *node) { assert(left != NULL); assert(right != NULL); assert(node != NULL); struct aggregator_bucket *fst[64] = { 0 }; struct aggregator_bucket *snd[64] = { 0 }; int fst_count = 0; int snd_count = 0; for (int i = 0; i < left->potential_buckets_count; i++) fst[fst_count++] = left->potential_buckets[i]; for (int i = 0; i < right->potential_buckets_count; i++) snd[snd_count++] = right->potential_buckets[i]; qsort(fst, fst_count, sizeof(struct aggregator_bucket *), aggregator_bucket_compare_wrapper); qsort(snd, snd_count, sizeof(struct aggregator_bucket *), aggregator_bucket_compare_wrapper); struct aggregator_bucket *output[64] = { 0 }; int output_count = 0; int i = 0; int j = 0; while (i < left->potential_buckets_count && j < right->potential_buckets_count) { int res = aggregator_bucket_compare(left->potential_buckets[i], right->potential_buckets[j]); if (res == 0) { output[output_count++] = left->potential_buckets[i]; i++; j++; } else if (res == -1) i++; else if (res == 1) j++; else bug("Impossible"); } // strictly greater for (int k = 1; k < output_count; k++) assert(output[k - 1] < output[k]); // duplicates for (int k = 0; k < output_count; k++) for (int l = k + 1; l < output_count; l++) assert(output[k] != output[l]); for (int k = 0; k < output_count; k++) { if (node->potential_buckets_count >= MAX_POTENTIAL_BUCKETS_COUNT) break; node->potential_buckets[node->potential_buckets_count++] = output[k]; } } /* * Check if sets of potential buckets of two nodes are disjoint */ static int bucket_sets_are_disjoint(const struct trie_node *left, const struct trie_node *right) { assert(left != NULL); assert(right != NULL); if (left->potential_buckets_count == 0 || right->potential_buckets_count == 0) { log("Buckets are disjoint"); return 1; } int i = 0; int j = 0; while (i < left->potential_buckets_count && j < right->potential_buckets_count) { int res = aggregator_bucket_compare(left->potential_buckets[i], right->potential_buckets[j]); if (res == 0) return 0; else if (res == -1) i++; else if (res == 1) j++; else bug("Impossible"); } return 1; } /* * Second pass of Optimal Route Table Construction (ORTC) algorithm */ static void second_pass(struct trie_node *node) { assert(node != NULL); assert(node->potential_buckets_count <= MAX_POTENTIAL_BUCKETS_COUNT); //if (node->parent == NULL) //assert(node->bucket != NULL); if (is_leaf(node)) { assert(node->potential_buckets_count > 0); assert(node->potential_buckets[0] != NULL); assert(node->potential_buckets[0] == node->bucket); return; } struct trie_node * const left = node->child[0]; struct trie_node * const right = node->child[1]; assert(left != NULL); assert(right != NULL); /* Postorder traversal */ second_pass(left); second_pass(right); // duplicates for (int i = 0; i < left->potential_buckets_count; i++) for (int j = i + 1; j < left->potential_buckets_count; j++) assert(left->potential_buckets[i] != left->potential_buckets[j]); for (int i = 0; i < right->potential_buckets_count; i++) for (int j = i + 1; j < right->potential_buckets_count; j++) assert(right->potential_buckets[i] != right->potential_buckets[j]); /* qsort(left->potential_buckets, left->potential_buckets_count, sizeof(struct aggregator_bucket *), aggregator_bucket_compare_wrapper); qsort(right->potential_buckets, right->potential_buckets_count, sizeof(struct aggregator_bucket *), aggregator_bucket_compare_wrapper); for (int i = 1; i < left->potential_buckets_count; i++) { assert((uintptr_t)left->potential_buckets[i - 1] < (uintptr_t)left->potential_buckets[i]); } for (int i = 1; i < right->potential_buckets_count; i++) { assert((uintptr_t)right->potential_buckets[i - 1] < (uintptr_t)right->potential_buckets[i]); } */ if (bucket_sets_are_disjoint(left, right)) unionize_buckets(left, right, node); else intersect_buckets(left, right, node); } /* * Check if @bucket is one of potential buckets in @node */ static int is_bucket_potential(const struct trie_node *node, const struct aggregator_bucket *bucket) { for (int i = 0; i < node->potential_buckets_count; i++) if (node->potential_buckets[i] == bucket) return 1; return 0; } static void remove_potential_buckets(struct trie_node *node) { for (int i = 0; i < node->potential_buckets_count; i++) node->potential_buckets[i] = NULL; node->potential_buckets_count = 0; } /* * Third pass of Optimal Route Table Construction (ORTC) algorithm */ static void third_pass(struct trie_node *node) { if (node == NULL) return; //if (node->parent == NULL) //assert(node->bucket != NULL); assert(node->potential_buckets_count <= MAX_POTENTIAL_BUCKETS_COUNT); /* Root is assigned any of its potential buckets */ if (node->parent == NULL) { assert(node->potential_buckets_count > 0); assert(node->potential_buckets[0] != NULL); //assert(node->bucket != NULL); node->bucket = node->potential_buckets[0]; goto descent; } const struct aggregator_bucket *inherited_bucket = get_ancestor_bucket(node); /* * If bucket inherited from ancestor is one of potential buckets of this node, * then this node doesn't need bucket because it inherits one. */ if (is_bucket_potential(node, inherited_bucket)) { node->bucket = NULL; remove_potential_buckets(node); } else { assert(node->potential_buckets_count > 0); node->bucket = node->potential_buckets[0]; } /* Preorder traversal */ descent: third_pass(node->child[0]); third_pass(node->child[1]); /* Leaves with no assigned bucket are removed */ if (node->bucket == NULL && is_leaf(node)) remove_node(node); } static void get_trie_prefix_count_helper(const struct trie_node *node, int *count) { if (is_leaf(node)) { *count += 1; return; } if (node->child[0]) get_trie_prefix_count_helper(node->child[0], count); if (node->child[1]) get_trie_prefix_count_helper(node->child[1], count); } static int get_trie_prefix_count(const struct trie_node *node) { int count = 0; get_trie_prefix_count_helper(node, &count); return count; } static void get_trie_depth_helper(const struct trie_node *node, int *result, int depth) { if (is_leaf(node)) { if (depth > *result) *result = depth; return; } if (node->child[0]) get_trie_depth_helper(node->child[0], result, depth + 1); if (node->child[1]) get_trie_depth_helper(node->child[1], result, depth + 1); } static int get_trie_depth(const struct trie_node *node) { int result = 0; get_trie_depth_helper(node, &result, 0); return result; } static void print_prefixes_ip4_helper(const struct trie_node *node, struct net_addr_ip4 *addr, int depth) { assert(node != NULL); if (is_leaf(node)) { log("%N\t-> %p", addr, node->bucket); return; } if (node->bucket != NULL) { log("%N\t-> %p", addr, node->bucket); } if (node->child[0]) { ip4_clrbit(&addr->prefix, depth); addr->pxlen = depth + 1; print_prefixes_ip4_helper(node->child[0], addr, depth + 1); } if (node->child[1]) { ip4_setbit(&addr->prefix, depth); addr->pxlen = depth + 1; print_prefixes_ip4_helper(node->child[1], addr, depth + 1); ip4_clrbit(&addr->prefix, depth); } } static void print_prefixes_ip6_helper(const struct trie_node *node, struct net_addr_ip6 *addr, int depth) { assert(node != NULL); if (is_leaf(node)) { log("%N\t-> %p", addr, node->bucket); return; } if (node->bucket != NULL) { log("%N\t-> %p", addr, node->bucket); } if (node->child[0]) { ip6_clrbit(&addr->prefix, depth); addr->pxlen = depth + 1; print_prefixes_ip6_helper(node->child[0], addr, depth + 1); } if (node->child[1]) { ip6_setbit(&addr->prefix, depth); addr->pxlen = depth + 1; print_prefixes_ip6_helper(node->child[1], addr, depth + 1); ip6_clrbit(&addr->prefix, depth); } } static void print_prefixes(const struct trie_node *node, int type) { if (type == NET_IP4) { struct net_addr_ip4 addr = { 0 }; net_fill_ip4((net_addr *)&addr, IP4_NONE, 0); print_prefixes_ip4_helper(node, &addr, 0); } else if (type == NET_IP6) { struct net_addr_ip6 addr = { 0 }; net_fill_ip6((net_addr *)&addr, IP6_NONE, 0); print_prefixes_ip6_helper(node, &addr, 0); } } static void create_route_ip4(struct aggregator_proto *p, const struct net_addr_ip4 *addr, struct aggregator_bucket *bucket) { struct { struct network net; union net_addr_union u; } net_placeholder; assert(addr->type == NET_IP4); net_copy_ip4((struct net_addr_ip4 *)&net_placeholder.net.n.addr, addr); aggregator_bucket_update(p, bucket, &net_placeholder.net); } static void create_route_ip6(struct aggregator_proto *p, struct net_addr_ip6 *addr, struct aggregator_bucket *bucket) { struct { struct network n; union net_addr_union u; } net_placeholder; assert(addr->type == NET_IP6); net_copy_ip6((struct net_addr_ip6 *)&net_placeholder.n.n.addr, addr); aggregator_bucket_update(p, bucket, &net_placeholder.n); } static void collect_prefixes_helper_ip4(const struct trie_node *node, struct net_addr_ip4 *addr, struct aggregator_proto *p, int depth, int *count) { assert(node != NULL); if (is_leaf(node)) { assert(node->bucket != NULL); create_route_ip4(p, addr, node->bucket); *count += 1; return; } if (node->bucket != NULL) { create_route_ip4(p, addr, node->bucket); *count += 1; } if (node->child[0]) { ip4_clrbit(&addr->prefix, depth); addr->pxlen = depth + 1; collect_prefixes_helper_ip4(node->child[0], addr, p, depth + 1, count); } if (node->child[1]) { ip4_setbit(&addr->prefix, depth); addr->pxlen = depth + 1; collect_prefixes_helper_ip4(node->child[1], addr, p, depth + 1, count); ip4_clrbit(&addr->prefix, depth); } } static void collect_prefixes_helper_ip6(const struct trie_node *node, struct net_addr_ip6 *addr, struct aggregator_proto *p, int depth, int *count) { assert(node != NULL); if (is_leaf(node)) { assert(node->bucket != NULL); create_route_ip6(p, addr, node->bucket); *count += 1; return; } if (node->bucket != NULL) { create_route_ip6(p, addr, node->bucket); *count += 1; } if (node->child[0]) { ip6_clrbit(&addr->prefix, depth); addr->pxlen = depth + 1; collect_prefixes_helper_ip6(node->child[0], addr, p, depth + 1, count); } if (node->child[1]) { ip6_setbit(&addr->prefix, depth); addr->pxlen = depth + 1; collect_prefixes_helper_ip6(node->child[1], addr, p, depth + 1, count); ip6_clrbit(&addr->prefix, depth); } } static void collect_prefixes(struct aggregator_proto *p) { int count = 0; if (p->addr_type == NET_IP4) { struct net_addr_ip4 addr = { 0 }; net_fill_ip4((net_addr *)&addr, IP4_NONE, 0); collect_prefixes_helper_ip4(p->root, &addr, p, 0, &count); } else if (p->addr_type == NET_IP6) { struct net_addr_ip6 addr = { 0 }; net_fill_ip6((net_addr *)&addr, IP6_NONE, 0); collect_prefixes_helper_ip6(p->root, &addr, p, 0, &count); } else bug("Invalid NET type"); log("%d prefixes collected", count); } /* * Run Optimal Routing Table Constructor (ORTC) algorithm */ static void calculate_trie(void *P) { struct aggregator_proto *p = (struct aggregator_proto *)P; assert(p->addr_type == NET_IP4 || p->addr_type == NET_IP6); log("====PREFIXES BEFORE ===="); first_pass(p->root, p->trie_slab); log("====FIRST PASS===="); print_prefixes(p->root, p->addr_type); second_pass(p->root); log("====SECOND PASS===="); print_prefixes(p->root, p->addr_type); third_pass(p->root); log("====THIRD PASS===="); print_prefixes(p->root, p->addr_type); collect_prefixes(p); log("==== AGGREGATION DONE ===="); } /* * Set static attribute in @rta from static attribute in @old according to @sa. */ static void rta_set_static_attr(struct rta *rta, const struct rta *old, struct f_static_attr sa) { switch (sa.sa_code) { case SA_NET: break; case SA_FROM: rta->from = old->from; break; case SA_GW: rta->dest = RTD_UNICAST; rta->nh.gw = old->nh.gw; rta->nh.iface = old->nh.iface; rta->nh.next = NULL; rta->hostentry = NULL; rta->nh.labels = 0; break; case SA_SCOPE: rta->scope = old->scope; break; case SA_DEST: rta->dest = old->dest; rta->nh.gw = IPA_NONE; rta->nh.iface = NULL; rta->nh.next = NULL; rta->hostentry = NULL; rta->nh.labels = 0; break; case SA_IFNAME: rta->dest = RTD_UNICAST; rta->nh.gw = IPA_NONE; rta->nh.iface = old->nh.iface; rta->nh.next = NULL; rta->hostentry = NULL; rta->nh.labels = 0; break; case SA_GW_MPLS: rta->nh.labels = old->nh.labels; memcpy(&rta->nh.label, &old->nh.label, sizeof(u32) * old->nh.labels); break; case SA_WEIGHT: rta->nh.weight = old->nh.weight; break; case SA_PREF: rta->pref = old->pref; break; default: bug("Invalid static attribute access (%u/%u)", sa.f_type, sa.sa_code); } } /* * Compare list of &f_val entries. * @count: number of &f_val entries */ static int same_val_list(const struct f_val *v1, const struct f_val *v2, uint len) { for (uint i = 0; i < len; i++) if (!val_same(&v1[i], &v2[i])) return 0; return 1; } /* * Create and export new merged route. * @old: first route in a sequence of equivalent routes that are to be merged * @rte_val: first element in a sequence of equivalent rte_val_list entries * @length: number of equivalent routes that are to be merged (at least 1) * @ail: aggregation list */ static void aggregator_bucket_update(struct aggregator_proto *p, struct aggregator_bucket *bucket, struct network *net) { /* Empty bucket */ if (!bucket->rte) { rte_update2(p->dst, net->n.addr, NULL, bucket->last_src); bucket->last_src = NULL; return; } /* Allocate RTA and EA list */ struct rta *rta = allocz(rta_size(bucket->rte->attrs)); rta->dest = RTD_UNREACHABLE; rta->source = RTS_AGGREGATED; rta->scope = SCOPE_UNIVERSE; struct ea_list *eal = allocz(sizeof(struct ea_list) + sizeof(struct eattr) * p->aggr_on_da_count); eal->next = NULL; eal->count = 0; rta->eattrs = eal; /* Seed the attributes from aggregator rule */ for (uint i = 0; i < p->aggr_on_count; i++) { if (p->aggr_on[i].type == AGGR_ITEM_DYNAMIC_ATTR) { u32 ea_code = p->aggr_on[i].da.ea_code; const struct eattr *e = ea_find(bucket->rte->attrs->eattrs, ea_code); if (e) eal->attrs[eal->count++] = *e; } else if (p->aggr_on[i].type == AGGR_ITEM_STATIC_ATTR) rta_set_static_attr(rta, bucket->rte->attrs, p->aggr_on[i].sa); } struct rte *new = rte_get_temp(rta, p->p.main_source); new->net = net; log("=============== CREATE MERGED ROUTE ==============="); log("New route created: id = %d, protocol: %s", new->src->global_id, new->src->proto->name); log("==================================================="); /* merge filter needs one argument called "routes" */ struct f_val val = { .type = T_ROUTES_BLOCK, .val.rte = bucket->rte, }; /* Actually run the filter */ enum filter_return fret = f_eval_rte(p->merge_by, &new, rte_update_pool, 1, &val, 0); /* Src must be stored now, rte_update2() may return new */ struct rte_src *new_src = new ? new->src : NULL; /* Finally import the route */ switch (fret) { /* Pass the route to the protocol */ case F_ACCEPT: rte_update2(p->dst, net->n.addr, new, bucket->last_src ?: new->src); break; /* Something bad happened */ default: ASSERT_DIE(fret == F_ERROR); /* fall through */ /* We actually don't want this route */ case F_REJECT: if (bucket->last_src) rte_update2(p->dst, net->n.addr, NULL, bucket->last_src); break; } /* Switch source lock for bucket->last_src */ if (bucket->last_src != new_src) { if (new_src) rt_lock_source(new_src); if (bucket->last_src) rt_unlock_source(bucket->last_src); bucket->last_src = new_src; } } /* * Reload all the buckets on reconfiguration if merge filter has changed. * TODO: make this splitted */ static void aggregator_reload_buckets(void *data) { struct aggregator_proto *p = data; HASH_WALK(p->buckets, next_hash, b) if (b->rte) { aggregator_bucket_update(p, b, b->rte->net); lp_flush(rte_update_pool); } HASH_WALK_END; } /* * Evaluate static attribute of @rt1 according to @sa * and store result in @pos. */ static void eval_static_attr(const struct rte *rt1, struct f_static_attr sa, struct f_val *pos) { const struct rta *rta = rt1->attrs; #define RESULT(_type, value, result) \ do { \ pos->type = _type; \ pos->val.value = result; \ } while (0) switch (sa.sa_code) { case SA_NET: RESULT(sa.f_type, net, rt1->net->n.addr); break; case SA_FROM: RESULT(sa.f_type, ip, rta->from); break; case SA_GW: RESULT(sa.f_type, ip, rta->nh.gw); break; case SA_PROTO: RESULT(sa.f_type, s, rt1->src->proto->name); break; case SA_SOURCE: RESULT(sa.f_type, i, rta->source); break; case SA_SCOPE: RESULT(sa.f_type, i, rta->scope); break; case SA_DEST: RESULT(sa.f_type, i, rta->dest); break; case SA_IFNAME: RESULT(sa.f_type, s, rta->nh.iface ? rta->nh.iface->name : ""); break; case SA_IFINDEX: RESULT(sa.f_type, i, rta->nh.iface ? rta->nh.iface->index : 0); break; case SA_WEIGHT: RESULT(sa.f_type, i, rta->nh.weight + 1); break; case SA_PREF: RESULT(sa.f_type, i, rta->pref); break; case SA_GW_MPLS: RESULT(sa.f_type, i, rta->nh.labels ? rta->nh.label[0] : MPLS_NULL); break; default: bug("Invalid static attribute access (%u/%u)", sa.f_type, sa.sa_code); } #undef RESULT } /* * Evaluate dynamic attribute of @rt1 according to @da * and store result in @pos. */ static void eval_dynamic_attr(const struct rte *rt1, struct f_dynamic_attr da, struct f_val *pos) { const struct rta *rta = rt1->attrs; const struct eattr *e = ea_find(rta->eattrs, da.ea_code); #define RESULT(_type, value, result) \ do { \ pos->type = _type; \ pos->val.value = result; \ } while (0) #define RESULT_VOID \ do { \ pos->type = T_VOID; \ } while (0) if (!e) { /* A special case: undefined as_path looks like empty as_path */ if (da.type == EAF_TYPE_AS_PATH) { RESULT(T_PATH, ad, &null_adata); return; } /* The same special case for int_set */ if (da.type == EAF_TYPE_INT_SET) { RESULT(T_CLIST, ad, &null_adata); return; } /* The same special case for ec_set */ if (da.type == EAF_TYPE_EC_SET) { RESULT(T_ECLIST, ad, &null_adata); return; } /* The same special case for lc_set */ if (da.type == EAF_TYPE_LC_SET) { RESULT(T_LCLIST, ad, &null_adata); return; } /* Undefined value */ RESULT_VOID; return; } switch (e->type & EAF_TYPE_MASK) { case EAF_TYPE_INT: RESULT(da.f_type, i, e->u.data); break; case EAF_TYPE_ROUTER_ID: RESULT(T_QUAD, i, e->u.data); break; case EAF_TYPE_OPAQUE: RESULT(T_ENUM_EMPTY, i, 0); break; case EAF_TYPE_IP_ADDRESS: RESULT(T_IP, ip, *((ip_addr *) e->u.ptr->data)); break; case EAF_TYPE_AS_PATH: RESULT(T_PATH, ad, e->u.ptr); break; case EAF_TYPE_BITFIELD: RESULT(T_BOOL, i, !!(e->u.data & (1u << da.bit))); break; case EAF_TYPE_INT_SET: RESULT(T_CLIST, ad, e->u.ptr); break; case EAF_TYPE_EC_SET: RESULT(T_ECLIST, ad, e->u.ptr); break; case EAF_TYPE_LC_SET: RESULT(T_LCLIST, ad, e->u.ptr); break; default: bug("Unknown dynamic attribute type"); } #undef RESULT #undef RESULT_VOID } static inline u32 aggr_route_hash(const rte *e) { struct { net *net; struct rte_src *src; } obj = { .net = e->net, .src = e->src, }; return mem_hash(&obj, sizeof obj); } #define AGGR_RTE_KEY(n) (&(n)->rte) #define AGGR_RTE_NEXT(n) ((n)->next_hash) #define AGGR_RTE_EQ(a,b) (((a)->src == (b)->src) && ((a)->net == (b)->net)) #define AGGR_RTE_FN(_n) aggr_route_hash(_n) #define AGGR_RTE_ORDER 4 /* Initial */ #define AGGR_RTE_REHASH aggr_rte_rehash #define AGGR_RTE_PARAMS /8, *2, 2, 2, 4, 24 HASH_DEFINE_REHASH_FN(AGGR_RTE, struct aggregator_route); #define AGGR_BUCK_KEY(n) (n) #define AGGR_BUCK_NEXT(n) ((n)->next_hash) #define AGGR_BUCK_EQ(a,b) (((a)->hash == (b)->hash) && (same_val_list((a)->aggr_data, (b)->aggr_data, p->aggr_on_count))) #define AGGR_BUCK_FN(n) ((n)->hash) #define AGGR_BUCK_ORDER 4 /* Initial */ #define AGGR_BUCK_REHASH aggr_buck_rehash #define AGGR_BUCK_PARAMS /8, *2, 2, 2, 4, 24 HASH_DEFINE_REHASH_FN(AGGR_BUCK, struct aggregator_bucket); #define AGGR_DATA_MEMSIZE (sizeof(struct f_val) * p->aggr_on_count) static void aggregator_rt_notify(struct proto *P, struct channel *src_ch, net *net, rte *new, rte *old) { struct aggregator_proto *p = SKIP_BACK(struct aggregator_proto, p, P); ASSERT_DIE(src_ch == p->src); struct aggregator_bucket *new_bucket = NULL, *old_bucket = NULL; struct aggregator_route *old_route = NULL; /* Find the objects for the old route */ if (old) old_route = HASH_FIND(p->routes, AGGR_RTE, old); if (old_route) old_bucket = old_route->bucket; /* Find the bucket for the new route */ if (new) { /* Routes are identical, do nothing */ if (old_route && rte_same(&old_route->rte, new)) return; /* Evaluate route attributes. */ struct aggregator_bucket *tmp_bucket = sl_allocz(p->bucket_slab); for (uint val_idx = 0; val_idx < p->aggr_on_count; val_idx++) { int type = p->aggr_on[val_idx].type; switch (type) { case AGGR_ITEM_TERM: { const struct f_line *line = p->aggr_on[val_idx].line; struct rte *rt1 = new; enum filter_return fret = f_eval_rte(line, &new, rte_update_pool, 0, NULL, &tmp_bucket->aggr_data[val_idx]); if (rt1 != new) { rte_free(rt1); log(L_WARN "Aggregator rule modifies the route, reverting"); } if (fret > F_RETURN) log(L_WARN "%s.%s: Wrong number of items left on stack after evaluation of aggregation list", rt1->src->proto->name, rt1->sender); break; } case AGGR_ITEM_STATIC_ATTR: { struct f_val *pos = &tmp_bucket->aggr_data[val_idx]; eval_static_attr(new, p->aggr_on[val_idx].sa, pos); break; } case AGGR_ITEM_DYNAMIC_ATTR: { struct f_val *pos = &tmp_bucket->aggr_data[val_idx]; eval_dynamic_attr(new, p->aggr_on[val_idx].da, pos); break; } default: break; } } /* Compute the hash */ u64 haux; mem_hash_init(&haux); for (uint i = 0; i < p->aggr_on_count; i++) { mem_hash_mix_num(&haux, tmp_bucket->aggr_data[i].type); #define MX(k) mem_hash_mix(&haux, &IT(k), sizeof IT(k)); #define IT(k) tmp_bucket->aggr_data[i].val.k switch (tmp_bucket->aggr_data[i].type) { case T_VOID: break; case T_INT: case T_BOOL: case T_PAIR: case T_QUAD: case T_ENUM: MX(i); break; case T_EC: case T_RD: MX(ec); break; case T_LC: MX(lc); break; case T_IP: MX(ip); break; case T_NET: mem_hash_mix_num(&haux, net_hash(IT(net))); break; case T_STRING: mem_hash_mix_str(&haux, IT(s)); break; case T_PATH_MASK: mem_hash_mix(&haux, IT(path_mask), sizeof(*IT(path_mask)) + IT(path_mask)->len * sizeof (IT(path_mask)->item)); break; case T_PATH: case T_CLIST: case T_ECLIST: case T_LCLIST: mem_hash_mix(&haux, IT(ad)->data, IT(ad)->length); break; case T_PATH_MASK_ITEM: case T_ROUTE: case T_ROUTES_BLOCK: bug("Invalid type %s in hashing", f_type_name(tmp_bucket->aggr_data[i].type)); case T_SET: MX(t); break; case T_PREFIX_SET: MX(ti); break; } } tmp_bucket->hash = mem_hash_value(&haux); /* Find the existing bucket */ if (new_bucket = HASH_FIND(p->buckets, AGGR_BUCK, tmp_bucket)) sl_free(tmp_bucket); else { new_bucket = tmp_bucket; HASH_INSERT2(p->buckets, AGGR_BUCK, p->p.pool, new_bucket); } /* Store the route attributes */ if (rta_is_cached(new->attrs)) rta_clone(new->attrs); else new->attrs = rta_lookup(new->attrs); log("new rte: %p, net: %p, src: %p, hash: %x", new, new->net, new->src, aggr_route_hash(new)); /* Insert the new route into the bucket */ struct aggregator_route *arte = sl_alloc(p->route_slab); *arte = (struct aggregator_route) { .bucket = new_bucket, .rte = *new, }; arte->rte.next = new_bucket->rte, new_bucket->rte = &arte->rte; new_bucket->count++; HASH_INSERT2(p->routes, AGGR_RTE, p->p.pool, arte); log("Inserting rte: %p, arte: %p, net: %p, src: %p, hash: %x", &arte->rte, arte, arte->rte.net, arte->rte.src, aggr_route_hash(&arte->rte)); } /* Remove the old route from its bucket */ if (old_bucket) { for (struct rte **k = &old_bucket->rte; *k; k = &(*k)->next) if (*k == &old_route->rte) { *k = (*k)->next; break; } old_bucket->count--; HASH_REMOVE2(p->routes, AGGR_RTE, p->p.pool, old_route); rta_free(old_route->rte.attrs); sl_free(old_route); } HASH_WALK(p->buckets, next_hash, bucket) { for (const struct rte *rte = bucket->rte; rte; rte = rte->next) { union net_addr_union *uptr = (net_addr_union *)rte->net->n.addr; assert(uptr->n.type == NET_IP4 || uptr->n.type == NET_IP6); if (uptr->n.type == NET_IP4) { const struct net_addr_ip4 *addr = &uptr->ip4; trie_insert_prefix_ip4(addr, p->root, bucket, p->trie_slab); log("INSERT %N", addr); } else if (uptr->n.type == NET_IP6) { const struct net_addr_ip6 *addr = &uptr->ip6; trie_insert_prefix_ip6(addr, p->root, bucket, p->trie_slab); log("INSERT %N", addr); } } } HASH_WALK_END; if (p->net_present == 0) ev_schedule(&p->reload_trie); else { /* Announce changes */ if (old_bucket) aggregator_bucket_update(p, old_bucket, net); if (new_bucket && (new_bucket != old_bucket)) aggregator_bucket_update(p, new_bucket, net); } /* Cleanup the old bucket if empty */ if (old_bucket && (!old_bucket->rte || !old_bucket->count)) { ASSERT_DIE(!old_bucket->rte && !old_bucket->count); HASH_REMOVE2(p->buckets, AGGR_BUCK, p->p.pool, old_bucket); sl_free(old_bucket); } } static int aggregator_preexport(struct channel *C, struct rte *new) { struct aggregator_proto *p = SKIP_BACK(struct aggregator_proto, p, C->proto); /* Reject our own routes */ if (new->sender == p->dst) return -1; /* Disallow aggregating already aggregated routes */ if (new->attrs->source == RTS_AGGREGATED) { log(L_ERR "Multiple aggregations of the same route not supported in BIRD 2."); return -1; } return 0; } static void aggregator_postconfig(struct proto_config *CF) { struct aggregator_config *cf = SKIP_BACK(struct aggregator_config, c, CF); if (!cf->dst->table) cf_error("Source table not specified"); if (!cf->src->table) cf_error("Destination table not specified"); if (cf->dst->table->addr_type != cf->src->table->addr_type) cf_error("Both tables must be of the same type"); cf->dst->in_filter = cf->src->in_filter; cf->src->in_filter = FILTER_REJECT; cf->dst->out_filter = FILTER_REJECT; cf->dst->debug = cf->src->debug; } static struct proto * aggregator_init(struct proto_config *CF) { struct proto *P = proto_new(CF); struct aggregator_proto *p = SKIP_BACK(struct aggregator_proto, p, P); struct aggregator_config *cf = SKIP_BACK(struct aggregator_config, c, CF); proto_configure_channel(P, &p->src, cf->src); proto_configure_channel(P, &p->dst, cf->dst); p->aggr_on_count = cf->aggr_on_count; p->aggr_on_da_count = cf->aggr_on_da_count; p->aggr_on = cf->aggr_on; p->net_present = cf->net_present; p->merge_by = cf->merge_by; P->rt_notify = aggregator_rt_notify; P->preexport = aggregator_preexport; return P; } static int aggregator_start(struct proto *P) { struct aggregator_proto *p = SKIP_BACK(struct aggregator_proto, p, P); p->addr_type = p->src->table->addr_type; p->bucket_slab = sl_new(P->pool, sizeof(struct aggregator_bucket) + AGGR_DATA_MEMSIZE); HASH_INIT(p->buckets, P->pool, AGGR_BUCK_ORDER); p->route_slab = sl_new(P->pool, sizeof(struct aggregator_route)); HASH_INIT(p->routes, P->pool, AGGR_RTE_ORDER); p->reload_buckets = (event) { .hook = aggregator_reload_buckets, .data = p, }; p->trie_slab = sl_new(p->p.pool, sizeof(struct trie_node)); p->root = new_node(p->trie_slab); p->root->depth = 1; p->reload_trie = (event) { .hook = calculate_trie, .data = p, }; struct network *default_net = NULL; if (p->addr_type == NET_IP4) { default_net = mb_alloc(P->pool, sizeof(struct network) + sizeof(struct net_addr_ip4)); net_fill_ip4(default_net->n.addr, IP4_NONE, 0); log("Creating net %p for default route", default_net); } else if (p->addr_type == NET_IP6) { default_net = mb_alloc(P->pool, sizeof(struct network) + sizeof(struct net_addr_ip6)); net_fill_ip6(default_net->n.addr, IP6_NONE, 0); log("Creating net %p for default route", default_net); } /* Create route attributes with zero nexthop */ struct rta rta = { 0 }; /* Allocate bucket for root node */ struct aggregator_bucket *new_bucket = sl_allocz(p->bucket_slab); u64 haux = 0; mem_hash_init(&haux); new_bucket->hash = mem_hash_value(&haux); struct aggregator_route *arte = sl_alloc(p->route_slab); *arte = (struct aggregator_route) { .bucket = new_bucket, .rte = { .attrs = rta_lookup(&rta) }, }; arte->rte.next = new_bucket->rte; new_bucket->rte = &arte->rte; new_bucket->count++; arte->rte.net = default_net; default_net->routes = &arte->rte; HASH_INSERT2(p->routes, AGGR_RTE, p->p.pool, arte); HASH_INSERT2(p->buckets, AGGR_BUCK, p->p.pool, new_bucket); /* Assign default route to the root */ p->root->bucket = new_bucket; return PS_UP; } static int aggregator_shutdown(struct proto *P) { struct aggregator_proto *p = SKIP_BACK(struct aggregator_proto, p, P); HASH_WALK_DELSAFE(p->buckets, next_hash, b) { while (b->rte) { struct aggregator_route *arte = SKIP_BACK(struct aggregator_route, rte, b->rte); b->rte = arte->rte.next; b->count--; HASH_REMOVE(p->routes, AGGR_RTE, arte); rta_free(arte->rte.attrs); sl_free(arte); } ASSERT_DIE(b->count == 0); HASH_REMOVE(p->buckets, AGGR_BUCK, b); sl_free(b); } HASH_WALK_END; ev_postpone(&p->reload_trie); delete_trie(p->root); p->root = NULL; return PS_DOWN; } static int aggregator_reconfigure(struct proto *P, struct proto_config *CF) { struct aggregator_proto *p = SKIP_BACK(struct aggregator_proto, p, P); struct aggregator_config *cf = SKIP_BACK(struct aggregator_config, c, CF); TRACE(D_EVENTS, "Reconfiguring"); /* Compare numeric values (shortcut) */ if (cf->aggr_on_count != p->aggr_on_count) return 0; if (cf->aggr_on_da_count != p->aggr_on_da_count) return 0; /* Compare aggregator rule */ for (uint i = 0; i < p->aggr_on_count; i++) switch (cf->aggr_on[i].type) { case AGGR_ITEM_TERM: if (!f_same(cf->aggr_on[i].line, p->aggr_on[i].line)) return 0; break; case AGGR_ITEM_STATIC_ATTR: if (memcmp(&cf->aggr_on[i].sa, &p->aggr_on[i].sa, sizeof(struct f_static_attr)) != 0) return 0; break; case AGGR_ITEM_DYNAMIC_ATTR: if (memcmp(&cf->aggr_on[i].da, &p->aggr_on[i].da, sizeof(struct f_dynamic_attr)) != 0) return 0; break; default: bug("Broken aggregator rule"); } /* Compare merge filter */ if (!f_same(cf->merge_by, p->merge_by)) ev_schedule(&p->reload_buckets); p->aggr_on = cf->aggr_on; p->merge_by = cf->merge_by; return 1; } struct protocol proto_aggregator = { .name = "Aggregator", .template = "aggregator%d", .class = PROTOCOL_AGGREGATOR, .preference = 1, .channel_mask = NB_ANY, .proto_size = sizeof(struct aggregator_proto), .config_size = sizeof(struct aggregator_config), .postconfig = aggregator_postconfig, .init = aggregator_init, .start = aggregator_start, .shutdown = aggregator_shutdown, .reconfigure = aggregator_reconfigure, }; void aggregator_build(void) { proto_build(&proto_aggregator); }