From 8afbc0944f054a0a60d0e19e3db9852efb43f4ba Mon Sep 17 00:00:00 2001 From: Tian Lan Date: Fri, 15 Apr 2022 15:26:16 -0400 Subject: [PATCH] Add prefetch support for subnet cache entries - Entries in the subnet cache should now be prefetched. - Rename testdata subnet_*.crpl to subnet_*.rpl so they are visible to make test Signed-off-by: Tian Lan --- edns-subnet/subnetmod.c | 46 +++++++++------ edns-subnet/subnetmod.h | 8 +++ services/mesh.c | 127 +++++++++++++++++++++++++++++++++++++++- 3 files changed, 161 insertions(+), 20 deletions(-) diff --git a/edns-subnet/subnetmod.c b/edns-subnet/subnetmod.c index fcea71c31..02994b3ab 100644 --- a/edns-subnet/subnetmod.c +++ b/edns-subnet/subnetmod.c @@ -97,8 +97,8 @@ subnet_new_qstate(struct module_qstate *qstate, int id) } /** Add ecs struct to edns list, after parsing it to wire format. */ -static void -ecs_opt_list_append(struct ecs_data* ecs, struct edns_option** list, +void +subnet_ecs_opt_list_append(struct ecs_data* ecs, struct edns_option** list, struct module_qstate *qstate) { size_t sn_octs, sn_octs_remainder; @@ -164,7 +164,7 @@ int ecs_whitelist_check(struct query_info* qinfo, * set. */ if(!edns_opt_list_find(qstate->edns_opts_back_out, qstate->env->cfg->client_subnet_opcode)) { - ecs_opt_list_append(&sq->ecs_server_out, + subnet_ecs_opt_list_append(&sq->ecs_server_out, &qstate->edns_opts_back_out, qstate); } sq->subnet_sent = 1; @@ -231,7 +231,7 @@ subnetmod_init(struct module_env *env, int id) env->unique_mesh = 1; if(!edns_register_option(env->cfg->client_subnet_opcode, env->cfg->client_subnet_always_forward /* bypass cache */, - 0 /* no aggregation */, env)) { + 1 /* no aggregation */, env)) { log_err("subnetcache: could not register opcode"); ecs_whitelist_delete(sn_env->whitelist); slabhash_delete(sn_env->subnet_msg_cache); @@ -330,11 +330,15 @@ update_cache(struct module_qstate *qstate, int id) struct slabhash *subnet_msg_cache = sne->subnet_msg_cache; struct ecs_data *edns = &sq->ecs_client_in; size_t i; + hashvalue_type h; + + /* qinfo_hash is not set if it is prefetch request */ + if (qstate->minfo[id] && ((struct subnet_qstate*)qstate->minfo[id])->qinfo_hash) { + h = ((struct subnet_qstate*)qstate->minfo[id])->qinfo_hash; + } else { + h = query_info_hash(&qstate->qinfo, qstate->query_flags); + } - /* We already calculated hash upon lookup */ - hashvalue_type h = qstate->minfo[id] ? - ((struct subnet_qstate*)qstate->minfo[id])->qinfo_hash : - query_info_hash(&qstate->qinfo, qstate->query_flags); /* Step 1, general qinfo lookup */ struct lruhash_entry *lru_entry = slabhash_lookup(subnet_msg_cache, h, &qstate->qinfo, 1); @@ -380,7 +384,7 @@ update_cache(struct module_qstate *qstate, int id) log_err("subnetcache: cache insertion failed"); return; } - + /* store RRsets */ for(i=0; irrset_count; i++) { rep->ref[i].key = rep->rrsets[i]; @@ -402,7 +406,7 @@ update_cache(struct module_qstate *qstate, int id) /** Lookup in cache and reply true iff reply is sent. */ static int -lookup_and_reply(struct module_qstate *qstate, int id, struct subnet_qstate *sq) +lookup_and_reply(struct module_qstate *qstate, int id, struct subnet_qstate *sq, int prefetch) { struct lruhash_entry *e; struct module_env *env = qstate->env; @@ -451,6 +455,10 @@ lookup_and_reply(struct module_qstate *qstate, int id, struct subnet_qstate *sq) INET6_SIZE); sq->ecs_client_out.subnet_validdata = 1; } + + if (prefetch && *qstate->env->now > ((struct reply_info *)node->elem)->prefetch_ttl) { + qstate->need_refetch = 1; + } return 1; } @@ -487,7 +495,7 @@ eval_response(struct module_qstate *qstate, int id, struct subnet_qstate *sq) * module_finished */ return module_finished; } - + /* We have not asked for subnet data */ if (!sq->subnet_sent) { if (s_in->subnet_validdata) @@ -496,7 +504,7 @@ eval_response(struct module_qstate *qstate, int id, struct subnet_qstate *sq) cp_edns_bad_response(c_out, c_in); return module_finished; } - + /* subnet sent but nothing came back */ if (!s_in->subnet_validdata) { /* The authority indicated no support for edns subnet. As a @@ -513,11 +521,11 @@ eval_response(struct module_qstate *qstate, int id, struct subnet_qstate *sq) cp_edns_bad_response(c_out, c_in); return module_finished; } - + /* Being here means we have asked for and got a subnet specific * answer. Also, the answer from the authority is not yet cached * anywhere. */ - + /* can we accept response? */ if(s_out->subnet_addr_fam != s_in->subnet_addr_fam || s_out->subnet_source_mask != s_in->subnet_source_mask || @@ -602,7 +610,7 @@ parse_subnet_option(struct edns_option* ecs_option, struct ecs_data* ecs) return 1; } -static void +void subnet_option_from_ss(struct sockaddr_storage *ss, struct ecs_data* ecs, struct config_file* cfg) { @@ -759,13 +767,13 @@ subnetmod_operate(struct module_qstate *qstate, enum module_ev event, } lock_rw_wrlock(&sne->biglock); - if (lookup_and_reply(qstate, id, sq)) { + if (qstate->mesh_info->reply_list && lookup_and_reply(qstate, id, sq, qstate->env->cfg->prefetch)) { sne->num_msg_cache++; lock_rw_unlock(&sne->biglock); verbose(VERB_QUERY, "subnetcache: answered from cache"); qstate->ext_state[id] = module_finished; - ecs_opt_list_append(&sq->ecs_client_out, + subnet_ecs_opt_list_append(&sq->ecs_client_out, &qstate->edns_opts_front_out, qstate); return; } @@ -787,7 +795,7 @@ subnetmod_operate(struct module_qstate *qstate, enum module_ev event, sq->ecs_server_out.subnet_source_mask = qstate->env->cfg->max_client_subnet_ipv6; /* Safe to copy completely, even if the source is limited by the - * configuration. ecs_opt_list_append() will limit the address. + * configuration. subnet_ecs_opt_list_append() will limit the address. * */ memcpy(&sq->ecs_server_out.subnet_addr, sq->ecs_client_in.subnet_addr, INET6_SIZE); @@ -811,7 +819,7 @@ subnetmod_operate(struct module_qstate *qstate, enum module_ev event, qstate->ext_state[id] = eval_response(qstate, id, sq); if(qstate->ext_state[id] == module_finished && qstate->return_msg) { - ecs_opt_list_append(&sq->ecs_client_out, + subnet_ecs_opt_list_append(&sq->ecs_client_out, &qstate->edns_opts_front_out, qstate); } qstate->no_cache_store = sq->started_no_cache_store; diff --git a/edns-subnet/subnetmod.h b/edns-subnet/subnetmod.h index 27ba2ee74..8e6ccd66e 100644 --- a/edns-subnet/subnetmod.h +++ b/edns-subnet/subnetmod.h @@ -143,4 +143,12 @@ int ecs_query_response(struct module_qstate* qstate, struct dns_msg* response, /** mark subnet msg to be deleted */ void subnet_markdel(void* key); +/** Add ecs struct to edns list, after parsing it to wire format. */ +void subnet_ecs_opt_list_append(struct ecs_data* ecs, struct edns_option** list, + struct module_qstate *qstate); + +/** Create ecs_data from the sockaddr_storage information. */ +void subnet_option_from_ss(struct sockaddr_storage *ss, struct ecs_data* ecs, + struct config_file* cfg); + #endif /* SUBNETMOD_H */ diff --git a/services/mesh.c b/services/mesh.c index 4b022d47f..1f3eadad2 100644 --- a/services/mesh.c +++ b/services/mesh.c @@ -64,6 +64,11 @@ #include "respip/respip.h" #include "services/listen_dnsport.h" +#ifdef CLIENT_SUBNET +#include "edns-subnet/subnetmod.h" +#include "edns-subnet/edns-subnet.h" +#endif + /** subtract timers and the values do not overflow or become negative */ static void timeval_subtract(struct timeval* d, const struct timeval* end, const struct timeval* start) @@ -683,6 +688,107 @@ mesh_new_callback(struct mesh_area* mesh, struct query_info* qinfo, return 1; } +#ifdef CLIENT_SUBNET +/* Same logic as mesh_schedule_prefetch but tailored to the subnet module logic + * like passing along the comm_reply info. This will be faked into an EDNS + * option for processing by the subnet module if the client has not already + * attached its own ECS data. */ +static void mesh_schedule_prefetch_subnet(struct mesh_area* mesh, + struct query_info* qinfo, uint16_t qflags, time_t leeway, int run, + int rpz_passthru, struct mesh_state* mstate, + struct sockaddr_storage *client_addr) +{ + struct mesh_state* s = NULL; + struct edns_option* opt = NULL; +#ifdef UNBOUND_DEBUG + struct rbnode_type* n; +#endif + + if(!mesh_make_new_space(mesh, NULL)) { + verbose(VERB_ALGO, "Too many queries. dropped prefetch."); + mesh->stats_dropped ++; + return; + } + + s = mesh_state_create(mesh->env, qinfo, NULL, + qflags&(BIT_RD|BIT_CD), 0, 0); + if(!s) { + log_err("prefetch_subnet mesh_state_create: out of memory"); + return; + } + + mesh_state_make_unique(s); + + opt = edns_opt_list_find(mstate->s.edns_opts_front_in, mesh->env->cfg->client_subnet_opcode); + if(opt) { + /* Use the client's ECS data */ + if(!edns_opt_list_append(&s->s.edns_opts_front_in, opt->opt_code, + opt->opt_len, opt->opt_data, s->s.region)) { + log_err("prefetch_subnet edns_opt_list_append: out of memory"); + return; + } + } else { + /* Fake the ECS data from the client's IP */ + struct ecs_data ecs; + memset(&ecs, 0, sizeof(ecs)); + subnet_option_from_ss(client_addr, &ecs, mesh->env->cfg); + + if(ecs.subnet_validdata == 0) { + log_err("prefetch_subnet subnet_option_from_ss: invalid data"); + return; + } + + subnet_ecs_opt_list_append(&ecs, &s->s.edns_opts_front_in, &s->s); + if(!s->s.edns_opts_front_in) { + log_err("prefetch_subnet subnet_ecs_opt_list_append: out of memory"); + return; + } + } +#ifdef UNBOUND_DEBUG + n = +#else + (void) +#endif + rbtree_insert(&mesh->all, &s->node); + log_assert(n != NULL); + /* set detached (it is now) */ + mesh->num_detached_states++; + /* make it ignore the cache */ + sock_list_insert(&s->s.blacklist, NULL, 0, s->s.region); + s->s.prefetch_leeway = leeway; + + if(s->list_select == mesh_no_list) { + /* move to either the forever or the jostle_list */ + if(mesh->num_forever_states < mesh->max_forever_states) { + mesh->num_forever_states ++; + mesh_list_insert(s, &mesh->forever_first, + &mesh->forever_last); + s->list_select = mesh_forever_list; + } else { + mesh_list_insert(s, &mesh->jostle_first, + &mesh->jostle_last); + s->list_select = mesh_jostle_list; + } + } + + s->s.rpz_passthru = rpz_passthru; + + if(!run) { +#ifdef UNBOUND_DEBUG + n = +#else + (void) +#endif + rbtree_insert(&mesh->run, &s->run_node); + log_assert(n != NULL); + return; + } + + mesh_state_delete(&mstate->s); + mesh_run(mesh, s, module_event_new, NULL); +} +#endif /* CLIENT_SUBNET */ + /* Internal backend routine of mesh_new_prefetch(). It takes one additional * parameter, 'run', which controls whether to run the prefetch state * immediately. When this function is called internally 'run' could be @@ -1699,6 +1805,11 @@ mesh_continue(struct mesh_area* mesh, struct mesh_state* mstate, struct query_info* qinfo = NULL; uint16_t qflags; int rpz_p = 0; + struct sockaddr_storage client_addr; + + if (mstate->reply_list) { + client_addr = mstate->reply_list->query_reply.addr; + } mesh_query_done(mstate); mesh_walk_supers(mesh, mstate); @@ -1712,10 +1823,24 @@ mesh_continue(struct mesh_area* mesh, struct mesh_state* mstate, rpz_p = mstate->s.rpz_passthru; } - mesh_state_delete(&mstate->s); if(qinfo) { +#ifdef CLIENT_SUBNET + if(modstack_find(&mesh->mods, "subnetcache") != -1 ) { + mesh_schedule_prefetch_subnet(mesh, qinfo, qflags, + 0, 1, rpz_p, mstate, &client_addr); + } + else { + mesh_state_delete(&mstate->s); + mesh_schedule_prefetch(mesh, qinfo, qflags, + 0, 1, rpz_p); + } +#else + mesh_state_delete(&mstate->s); mesh_schedule_prefetch(mesh, qinfo, qflags, 0, 1, rpz_p); +#endif + } else { + mesh_state_delete(&mstate->s); } return 0; } -- 2.47.2