/*
 * services/cache/infra.c - infrastructure cache, server rtt and capabilities
 *
 * Copyright (c) 2007, NLnet Labs. All rights reserved.
 *
 * This software is open source.
 * 
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 
 * Redistributions of source code must retain the above copyright notice,
 * this list of conditions and the following disclaimer.
 * 
 * Redistributions in binary form must reproduce the above copyright notice,
 * this list of conditions and the following disclaimer in the documentation
 * and/or other materials provided with the distribution.
 * 
 * Neither the name of the NLNET LABS nor the names of its contributors may
 * be used to endorse or promote products derived from this software without
 * specific prior written permission.
 * 
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
 * TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

/**
 * \file
 *
 * This file contains the infrastructure cache.
 */
#include "config.h"
#include "sldns/rrdef.h"
#include "sldns/str2wire.h"
#include "sldns/sbuffer.h"
#include "sldns/wire2str.h"
#include "services/cache/infra.h"
#include "util/storage/slabhash.h"
#include "util/storage/lookup3.h"
#include "util/data/dname.h"
#include "util/log.h"
#include "util/net_help.h"
#include "util/config_file.h"
#include "iterator/iterator.h"

/** ratelimit value for delegation point */
int infra_dp_ratelimit = 0;

/** ratelimit value for client ip addresses,
 *  in queries per second. */
int infra_ip_ratelimit = 0;

/** ratelimit value for client ip addresses,
 *  in queries per second.
 *  For clients with a valid DNS Cookie. */
int infra_ip_ratelimit_cookie = 0;

/** Minus 1000 because that is outside of the RTTBAND, so
 * blacklisted servers stay blacklisted if this is chosen.
 * If USEFUL_SERVER_TOP_TIMEOUT is below 1000 (configured via RTT_MAX_TIMEOUT,
 * infra-cache-max-rtt) change it to just above the RTT_BAND. */
int
still_useful_timeout()
{
        return
        USEFUL_SERVER_TOP_TIMEOUT < 1000 ||
        USEFUL_SERVER_TOP_TIMEOUT - 1000 <= RTT_BAND
                ?RTT_BAND + 1
                :USEFUL_SERVER_TOP_TIMEOUT - 1000;
}

size_t 
infra_sizefunc(void* k, void* ATTR_UNUSED(d))
{
        struct infra_key* key = (struct infra_key*)k;
        return sizeof(*key) + sizeof(struct infra_data) + key->namelen
                + lock_get_mem(&key->entry.lock);
}

int 
infra_compfunc(void* key1, void* key2)
{
        struct infra_key* k1 = (struct infra_key*)key1;
        struct infra_key* k2 = (struct infra_key*)key2;
        int r = sockaddr_cmp(&k1->addr, k1->addrlen, &k2->addr, k2->addrlen);
        if(r != 0)
                return r;
        if(k1->namelen != k2->namelen) {
                if(k1->namelen < k2->namelen)
                        return -1;
                return 1;
        }
        return query_dname_compare(k1->zonename, k2->zonename);
}

void 
infra_delkeyfunc(void* k, void* ATTR_UNUSED(arg))
{
        struct infra_key* key = (struct infra_key*)k;
        if(!key)
                return;
        lock_rw_destroy(&key->entry.lock);
        free(key->zonename);
        free(key);
}

void 
infra_deldatafunc(void* d, void* ATTR_UNUSED(arg))
{
        struct infra_data* data = (struct infra_data*)d;
        free(data);
}

size_t 
rate_sizefunc(void* k, void* ATTR_UNUSED(d))
{
        struct rate_key* key = (struct rate_key*)k;
        return sizeof(*key) + sizeof(struct rate_data) + key->namelen
                + lock_get_mem(&key->entry.lock);
}

int 
rate_compfunc(void* key1, void* key2)
{
        struct rate_key* k1 = (struct rate_key*)key1;
        struct rate_key* k2 = (struct rate_key*)key2;
        if(k1->namelen != k2->namelen) {
                if(k1->namelen < k2->namelen)
                        return -1;
                return 1;
        }
        return query_dname_compare(k1->name, k2->name);
}

void 
rate_delkeyfunc(void* k, void* ATTR_UNUSED(arg))
{
        struct rate_key* key = (struct rate_key*)k;
        if(!key)
                return;
        lock_rw_destroy(&key->entry.lock);
        free(key->name);
        free(key);
}

void 
rate_deldatafunc(void* d, void* ATTR_UNUSED(arg))
{
        struct rate_data* data = (struct rate_data*)d;
        free(data);
}

/** find or create element in domainlimit tree */
static struct domain_limit_data* domain_limit_findcreate(
        struct rbtree_type* domain_limits, char* name)
{
        uint8_t* nm;
        int labs;
        size_t nmlen;
        struct domain_limit_data* d;

        /* parse name */
        nm = sldns_str2wire_dname(name, &nmlen);
        if(!nm) {
                log_err("could not parse %s", name);
                return NULL;
        }
        labs = dname_count_labels(nm);

        /* can we find it? */
        d = (struct domain_limit_data*)name_tree_find(domain_limits, nm,
                nmlen, labs, LDNS_RR_CLASS_IN);
        if(d) {
                free(nm);
                return d;
        }
        
        /* create it */
        d = (struct domain_limit_data*)calloc(1, sizeof(*d));
        if(!d) {
                free(nm);
                return NULL;
        }
        d->node.node.key = &d->node;
        d->node.name = nm;
        d->node.len = nmlen;
        d->node.labs = labs;
        d->node.dclass = LDNS_RR_CLASS_IN;
        d->lim = -1;
        d->below = -1;
        if(!name_tree_insert(domain_limits, &d->node, nm, nmlen, labs,
                LDNS_RR_CLASS_IN)) {
                log_err("duplicate element in domainlimit tree");
                free(nm);
                free(d);
                return NULL;
        }
        return d;
}

/** insert rate limit configuration into lookup tree */
static int infra_ratelimit_cfg_insert(struct rbtree_type* domain_limits,
        struct config_file* cfg)
{
        struct config_str2list* p;
        struct domain_limit_data* d;
        for(p = cfg->ratelimit_for_domain; p; p = p->next) {
                d = domain_limit_findcreate(domain_limits, p->str);
                if(!d)
                        return 0;
                d->lim = atoi(p->str2);
        }
        for(p = cfg->ratelimit_below_domain; p; p = p->next) {
                d = domain_limit_findcreate(domain_limits, p->str);
                if(!d)
                        return 0;
                d->below = atoi(p->str2);
        }
        return 1;
}

int
setup_domain_limits(struct rbtree_type* domain_limits, struct config_file* cfg)
{
        name_tree_init(domain_limits);
        if(!infra_ratelimit_cfg_insert(domain_limits, cfg)) {
                return 0;
        }
        name_tree_init_parents(domain_limits);
        return 1;
}

/** find or create element in wait limit netblock tree */
static struct wait_limit_netblock_info*
wait_limit_netblock_findcreate(struct rbtree_type* tree, char* str)
{
        struct sockaddr_storage addr;
        int net;
        socklen_t addrlen;
        struct wait_limit_netblock_info* d;

        if(!netblockstrtoaddr(str, 0, &addr, &addrlen, &net)) {
                log_err("cannot parse wait limit netblock '%s'", str);
                return 0;
        }

        /* can we find it? */
        d = (struct wait_limit_netblock_info*)addr_tree_find(tree, &addr,
                addrlen, net);
        if(d)
                return d;

        /* create it */
        d = (struct wait_limit_netblock_info*)calloc(1, sizeof(*d));
        if(!d)
                return NULL;
        d->limit = -1;
        if(!addr_tree_insert(tree, &d->node, &addr, addrlen, net)) {
                log_err("duplicate element in domainlimit tree");
                free(d);
                return NULL;
        }
        return d;
}


/** insert wait limit information into lookup tree */
static int
infra_wait_limit_netblock_insert(rbtree_type* wait_limits_netblock,
        rbtree_type* wait_limits_cookie_netblock, struct config_file* cfg)
{
        struct config_str2list* p;
        struct wait_limit_netblock_info* d;
        for(p = cfg->wait_limit_netblock; p; p = p->next) {
                d = wait_limit_netblock_findcreate(wait_limits_netblock,
                        p->str);
                if(!d)
                        return 0;
                d->limit = atoi(p->str2);
        }
        for(p = cfg->wait_limit_cookie_netblock; p; p = p->next) {
                d = wait_limit_netblock_findcreate(wait_limits_cookie_netblock,
                        p->str);
                if(!d)
                        return 0;
                d->limit = atoi(p->str2);
        }
        return 1;
}

/** Add a default wait limit netblock */
static int
wait_limit_netblock_default(struct rbtree_type* tree, char* str, int limit)
{
        struct wait_limit_netblock_info* d;
        d = wait_limit_netblock_findcreate(tree, str);
        if(!d)
                return 0;
        d->limit = limit;
        return 1;
}

int
setup_wait_limits(rbtree_type* wait_limits_netblock,
        rbtree_type* wait_limits_cookie_netblock, struct config_file* cfg)
{
        addr_tree_init(wait_limits_netblock);
        addr_tree_init(wait_limits_cookie_netblock);

        /* Insert defaults */
        /* The loopback address is separated from the rest of the network. */
        /* wait-limit-netblock: 127.0.0.0/8 -1 */
        if(!wait_limit_netblock_default(wait_limits_netblock, "127.0.0.0/8",
                -1))
                return 0;
        /* wait-limit-netblock: ::1/128 -1 */
        if(!wait_limit_netblock_default(wait_limits_netblock, "::1/128", -1))
                return 0;
        /* wait-limit-cookie-netblock: 127.0.0.0/8 -1 */
        if(!wait_limit_netblock_default(wait_limits_cookie_netblock,
                "127.0.0.0/8", -1))
                return 0;
        /* wait-limit-cookie-netblock: ::1/128 -1 */
        if(!wait_limit_netblock_default(wait_limits_cookie_netblock,
                "::1/128", -1))
                return 0;

        if(!infra_wait_limit_netblock_insert(wait_limits_netblock,
                wait_limits_cookie_netblock, cfg))
                return 0;
        addr_tree_init_parents(wait_limits_netblock);
        addr_tree_init_parents(wait_limits_cookie_netblock);
        return 1;
}

struct infra_cache* 
infra_create(struct config_file* cfg)
{
        struct infra_cache* infra = (struct infra_cache*)calloc(1, 
                sizeof(struct infra_cache));
        size_t maxmem = cfg->infra_cache_numhosts * (sizeof(struct infra_key)+
                sizeof(struct infra_data)+INFRA_BYTES_NAME);
        if(!infra) {
                return NULL;
        }
        infra->hosts = slabhash_create(cfg->infra_cache_slabs,
                INFRA_HOST_STARTSIZE, maxmem, &infra_sizefunc, &infra_compfunc,
                &infra_delkeyfunc, &infra_deldatafunc, NULL);
        if(!infra->hosts) {
                free(infra);
                return NULL;
        }
        infra->host_ttl = cfg->host_ttl;
        infra->infra_keep_probing = cfg->infra_keep_probing;
        infra_dp_ratelimit = cfg->ratelimit;
        infra->domain_rates = slabhash_create(cfg->ratelimit_slabs,
                INFRA_HOST_STARTSIZE, cfg->ratelimit_size,
                &rate_sizefunc, &rate_compfunc, &rate_delkeyfunc,
                &rate_deldatafunc, NULL);
        if(!infra->domain_rates) {
                infra_delete(infra);
                return NULL;
        }
        /* insert config data into ratelimits */
        if(!setup_domain_limits(&infra->domain_limits, cfg)) {
                infra_delete(infra);
                return NULL;
        }
        if(!setup_wait_limits(&infra->wait_limits_netblock,
                &infra->wait_limits_cookie_netblock, cfg)) {
                infra_delete(infra);
                return NULL;
        }
        infra_ip_ratelimit = cfg->ip_ratelimit;
        infra_ip_ratelimit_cookie = cfg->ip_ratelimit_cookie;
        infra->client_ip_rates = slabhash_create(cfg->ip_ratelimit_slabs,
            INFRA_HOST_STARTSIZE, cfg->ip_ratelimit_size, &ip_rate_sizefunc,
            &ip_rate_compfunc, &ip_rate_delkeyfunc, &ip_rate_deldatafunc, NULL);
        if(!infra->client_ip_rates) {
                infra_delete(infra);
                return NULL;
        }
        return infra;
}

/** delete domain_limit entries */
static void domain_limit_free(rbnode_type* n, void* ATTR_UNUSED(arg))
{
        if(n) {
                free(((struct domain_limit_data*)n)->node.name);
                free(n);
        }
}

void
domain_limits_free(struct rbtree_type* domain_limits)
{
        if(!domain_limits)
                return;
        traverse_postorder(domain_limits, domain_limit_free, NULL);
}

/** delete wait_limit_netblock_info entries */
static void wait_limit_netblock_del(rbnode_type* n, void* ATTR_UNUSED(arg))
{
        free(n);
}

void
wait_limits_free(struct rbtree_type* wait_limits_tree)
{
        if(!wait_limits_tree)
                return;
        traverse_postorder(wait_limits_tree, wait_limit_netblock_del,
                NULL);
}

void 
infra_delete(struct infra_cache* infra)
{
        if(!infra)
                return;
        slabhash_delete(infra->hosts);
        slabhash_delete(infra->domain_rates);
        domain_limits_free(&infra->domain_limits);
        slabhash_delete(infra->client_ip_rates);
        wait_limits_free(&infra->wait_limits_netblock);
        wait_limits_free(&infra->wait_limits_cookie_netblock);
        free(infra);
}

struct infra_cache* 
infra_adjust(struct infra_cache* infra, struct config_file* cfg)
{
        size_t maxmem;
        if(!infra)
                return infra_create(cfg);
        infra->host_ttl = cfg->host_ttl;
        infra->infra_keep_probing = cfg->infra_keep_probing;
        infra_dp_ratelimit = cfg->ratelimit;
        infra_ip_ratelimit = cfg->ip_ratelimit;
        infra_ip_ratelimit_cookie = cfg->ip_ratelimit_cookie;
        maxmem = cfg->infra_cache_numhosts * (sizeof(struct infra_key)+
                sizeof(struct infra_data)+INFRA_BYTES_NAME);
        /* divide cachesize by slabs and multiply by slabs, because if the
         * cachesize is not an even multiple of slabs, that is the resulting
         * size of the slabhash */
        if(!slabhash_is_size(infra->hosts, maxmem, cfg->infra_cache_slabs) ||
           !slabhash_is_size(infra->domain_rates, cfg->ratelimit_size,
                cfg->ratelimit_slabs) ||
           !slabhash_is_size(infra->client_ip_rates, cfg->ip_ratelimit_size,
                cfg->ip_ratelimit_slabs)) {
                infra_delete(infra);
                infra = infra_create(cfg);
        } else {
                /* reapply domain limits */
                traverse_postorder(&infra->domain_limits, domain_limit_free,
                        NULL);
                if(!setup_domain_limits(&infra->domain_limits, cfg)) {
                        infra_delete(infra);
                        return NULL;
                }
        }
        return infra;
}

/** calculate the hash value for a host key
 *  set use_port to a non-0 number to use the port in
 *  the hash calculation; 0 to ignore the port.*/
static hashvalue_type
hash_addr(struct sockaddr_storage* addr, socklen_t addrlen,
  int use_port)
{
        hashvalue_type h = 0xab;
        /* select the pieces to hash, some OS have changing data inside */
        if(addr_is_ip6(addr, addrlen)) {
                struct sockaddr_in6* in6 = (struct sockaddr_in6*)addr;
                h = hashlittle(&in6->sin6_family, sizeof(in6->sin6_family), h);
                if(use_port){
                        h = hashlittle(&in6->sin6_port, sizeof(in6->sin6_port), h);
                }
                h = hashlittle(&in6->sin6_addr, INET6_SIZE, h);
        } else {
                struct sockaddr_in* in = (struct sockaddr_in*)addr;
                h = hashlittle(&in->sin_family, sizeof(in->sin_family), h);
                if(use_port){
                        h = hashlittle(&in->sin_port, sizeof(in->sin_port), h);
                }
                h = hashlittle(&in->sin_addr, INET_SIZE, h);
        }
        return h;
}

/** calculate infra hash for a key */
static hashvalue_type
hash_infra(struct sockaddr_storage* addr, socklen_t addrlen, uint8_t* name)
{
        return dname_query_hash(name, hash_addr(addr, addrlen, 1));
}

/** lookup version that does not check host ttl (you check it) */
struct lruhash_entry* 
infra_lookup_nottl(struct infra_cache* infra, struct sockaddr_storage* addr,
        socklen_t addrlen, uint8_t* name, size_t namelen, int wr)
{
        struct infra_key k;
        k.addrlen = addrlen;
        memcpy(&k.addr, addr, addrlen);
        k.namelen = namelen;
        k.zonename = name;
        k.entry.hash = hash_infra(addr, addrlen, name);
        k.entry.key = (void*)&k;
        k.entry.data = NULL;
        return slabhash_lookup(infra->hosts, k.entry.hash, &k, wr);
}

/** init the data elements */
static void
data_entry_init(struct infra_cache* infra, struct lruhash_entry* e, 
        time_t timenow)
{
        struct infra_data* data = (struct infra_data*)e->data;
        data->ttl = timenow + infra->host_ttl;
        rtt_init(&data->rtt);
        data->edns_version = 0;
        data->edns_lame_known = 0;
        data->probedelay = 0;
        data->isdnsseclame = 0;
        data->rec_lame = 0;
        data->lame_type_A = 0;
        data->lame_other = 0;
        data->timeout_A = 0;
        data->timeout_AAAA = 0;
        data->timeout_other = 0;
}

/** 
 * Create and init a new entry for a host 
 * @param infra: infra structure with config parameters.
 * @param addr: host address.
 * @param addrlen: length of addr.
 * @param name: name of zone
 * @param namelen: length of name.
 * @param tm: time now.
 * @return: the new entry or NULL on malloc failure.
 */
static struct lruhash_entry*
new_entry(struct infra_cache* infra, struct sockaddr_storage* addr, 
        socklen_t addrlen, uint8_t* name, size_t namelen, time_t tm)
{
        struct infra_data* data;
        struct infra_key* key = (struct infra_key*)malloc(sizeof(*key));
        if(!key)
                return NULL;
        data = (struct infra_data*)malloc(sizeof(struct infra_data));
        if(!data) {
                free(key);
                return NULL;
        }
        key->zonename = memdup(name, namelen);
        if(!key->zonename) {
                free(key);
                free(data);
                return NULL;
        }
        key->namelen = namelen;
        lock_rw_init(&key->entry.lock);
        key->entry.hash = hash_infra(addr, addrlen, name);
        key->entry.key = (void*)key;
        key->entry.data = (void*)data;
        key->addrlen = addrlen;
        memcpy(&key->addr, addr, addrlen);
        data_entry_init(infra, &key->entry, tm);
        return &key->entry;
}

int 
infra_host(struct infra_cache* infra, struct sockaddr_storage* addr,
        socklen_t addrlen, uint8_t* nm, size_t nmlen, time_t timenow,
        int* edns_vs, uint8_t* edns_lame_known, int* to)
{
        struct lruhash_entry* e = infra_lookup_nottl(infra, addr, addrlen,
                nm, nmlen, 0);
        struct infra_data* data;
        int wr = 0;
        if(e && ((struct infra_data*)e->data)->ttl < timenow) {
                /* it expired, try to reuse existing entry */
                int old = ((struct infra_data*)e->data)->rtt.rto;
                time_t tprobe = ((struct infra_data*)e->data)->probedelay;
                uint8_t tA = ((struct infra_data*)e->data)->timeout_A;
                uint8_t tAAAA = ((struct infra_data*)e->data)->timeout_AAAA;
                uint8_t tother = ((struct infra_data*)e->data)->timeout_other;
                lock_rw_unlock(&e->lock);
                e = infra_lookup_nottl(infra, addr, addrlen, nm, nmlen, 1);
                if(e) {
                        /* if its still there we have a writelock, init */
                        /* re-initialise */
                        /* do not touch lameness, it may be valid still */
                        data_entry_init(infra, e, timenow);
                        wr = 1;
                        /* TOP_TIMEOUT remains on reuse */
                        if(old >= USEFUL_SERVER_TOP_TIMEOUT) {
                                ((struct infra_data*)e->data)->rtt.rto
                                        = USEFUL_SERVER_TOP_TIMEOUT;
                                ((struct infra_data*)e->data)->probedelay = tprobe;
                                ((struct infra_data*)e->data)->timeout_A = tA;
                                ((struct infra_data*)e->data)->timeout_AAAA = tAAAA;
                                ((struct infra_data*)e->data)->timeout_other = tother;
                        }
                }
        }
        if(!e) {
                /* insert new entry */
                if(!(e = new_entry(infra, addr, addrlen, nm, nmlen, timenow)))
                        return 0;
                data = (struct infra_data*)e->data;
                *edns_vs = data->edns_version;
                *edns_lame_known = data->edns_lame_known;
                *to = rtt_timeout(&data->rtt);
                slabhash_insert(infra->hosts, e->hash, e, data, NULL);
                return 1;
        }
        /* use existing entry */
        data = (struct infra_data*)e->data;
        *edns_vs = data->edns_version;
        *edns_lame_known = data->edns_lame_known;
        *to = rtt_timeout(&data->rtt);
        if(*to >= PROBE_MAXRTO && (infra->infra_keep_probing ||
                rtt_notimeout(&data->rtt)*4 <= *to)) {
                /* delay other queries, this is the probe query */
                if(!wr) {
                        lock_rw_unlock(&e->lock);
                        e = infra_lookup_nottl(infra, addr,addrlen,nm,nmlen, 1);
                        if(!e) { /* flushed from cache real fast, no use to
                                allocate just for the probedelay */
                                return 1;
                        }
                        data = (struct infra_data*)e->data;
                }
                /* add 999 to round up the timeout value from msec to sec,
                 * then add a whole second so it is certain that this probe
                 * has timed out before the next is allowed */
                data->probedelay = timenow + ((*to)+1999)/1000;
        }
        lock_rw_unlock(&e->lock);
        return 1;
}

int 
infra_set_lame(struct infra_cache* infra, struct sockaddr_storage* addr,
        socklen_t addrlen, uint8_t* nm, size_t nmlen, time_t timenow,
        int dnsseclame, int reclame, uint16_t qtype)
{
        struct infra_data* data;
        struct lruhash_entry* e;
        int needtoinsert = 0;
        e = infra_lookup_nottl(infra, addr, addrlen, nm, nmlen, 1);
        if(!e) {
                /* insert it */
                if(!(e = new_entry(infra, addr, addrlen, nm, nmlen, timenow))) {
                        log_err("set_lame: malloc failure");
                        return 0;
                }
                needtoinsert = 1;
        } else if( ((struct infra_data*)e->data)->ttl < timenow) {
                /* expired, reuse existing entry */
                data_entry_init(infra, e, timenow);
        }
        /* got an entry, now set the zone lame */
        data = (struct infra_data*)e->data;
        /* merge data (if any) */
        if(dnsseclame)
                data->isdnsseclame = 1;
        if(reclame)
                data->rec_lame = 1;
        if(!dnsseclame && !reclame && qtype == LDNS_RR_TYPE_A)
                data->lame_type_A = 1;
        if(!dnsseclame  && !reclame && qtype != LDNS_RR_TYPE_A)
                data->lame_other = 1;
        /* done */
        if(needtoinsert)
                slabhash_insert(infra->hosts, e->hash, e, e->data, NULL);
        else    { lock_rw_unlock(&e->lock); }
        return 1;
}

void 
infra_update_tcp_works(struct infra_cache* infra,
        struct sockaddr_storage* addr, socklen_t addrlen, uint8_t* nm,
        size_t nmlen)
{
        struct lruhash_entry* e = infra_lookup_nottl(infra, addr, addrlen,
                nm, nmlen, 1);
        struct infra_data* data;
        if(!e)
                return; /* doesn't exist */
        data = (struct infra_data*)e->data;
        if(data->rtt.rto >= RTT_MAX_TIMEOUT)
                /* do not disqualify this server altogether, it is better
                 * than nothing */
                data->rtt.rto = still_useful_timeout();
        lock_rw_unlock(&e->lock);
}

int 
infra_rtt_update(struct infra_cache* infra, struct sockaddr_storage* addr,
        socklen_t addrlen, uint8_t* nm, size_t nmlen, int qtype,
        int roundtrip, int orig_rtt, time_t timenow)
{
        struct lruhash_entry* e = infra_lookup_nottl(infra, addr, addrlen,
                nm, nmlen, 1);
        struct infra_data* data;
        int needtoinsert = 0, expired = 0;
        int rto = 1;
        time_t oldprobedelay = 0;
        if(!e) {
                if(!(e = new_entry(infra, addr, addrlen, nm, nmlen, timenow)))
                        return 0;
                needtoinsert = 1;
        } else if(((struct infra_data*)e->data)->ttl < timenow) {
                oldprobedelay = ((struct infra_data*)e->data)->probedelay;
                data_entry_init(infra, e, timenow);
                expired = 1;
        }
        /* have an entry, update the rtt */
        data = (struct infra_data*)e->data;
        if(roundtrip == -1) {
                if(needtoinsert || expired) {
                        /* timeout on entry that has expired before the timer
                         * keep old timeout from the function caller */
                        data->rtt.rto = orig_rtt;
                        data->probedelay = oldprobedelay;
                }
                rtt_lost(&data->rtt, orig_rtt);
                if(qtype == LDNS_RR_TYPE_A) {
                        if(data->timeout_A < TIMEOUT_COUNT_MAX)
                                data->timeout_A++;
                } else if(qtype == LDNS_RR_TYPE_AAAA) {
                        if(data->timeout_AAAA < TIMEOUT_COUNT_MAX)
                                data->timeout_AAAA++;
                } else {
                        if(data->timeout_other < TIMEOUT_COUNT_MAX)
                                data->timeout_other++;
                }
        } else {
                /* if we got a reply, but the old timeout was above server
                 * selection height, delete the timeout so the server is
                 * fully available again */
                if(rtt_unclamped(&data->rtt) >= USEFUL_SERVER_TOP_TIMEOUT)
                        rtt_init(&data->rtt);
                rtt_update(&data->rtt, roundtrip);
                data->probedelay = 0;
                if(qtype == LDNS_RR_TYPE_A)
                        data->timeout_A = 0;
                else if(qtype == LDNS_RR_TYPE_AAAA)
                        data->timeout_AAAA = 0;
                else    data->timeout_other = 0;
        }
        if(data->rtt.rto > 0)
                rto = data->rtt.rto;

        if(needtoinsert)
                slabhash_insert(infra->hosts, e->hash, e, e->data, NULL);
        else    { lock_rw_unlock(&e->lock); }
        return rto;
}

long long infra_get_host_rto(struct infra_cache* infra,
        struct sockaddr_storage* addr, socklen_t addrlen, uint8_t* nm,
        size_t nmlen, struct rtt_info* rtt, int* delay, time_t timenow,
        int* tA, int* tAAAA, int* tother)
{
        struct lruhash_entry* e = infra_lookup_nottl(infra, addr, addrlen,
                nm, nmlen, 0);
        struct infra_data* data;
        long long ttl = -2;
        if(!e) return -1;
        data = (struct infra_data*)e->data;
        if(data->ttl >= timenow) {
                ttl = (long long)(data->ttl - timenow);
                memmove(rtt, &data->rtt, sizeof(*rtt));
                if(timenow < data->probedelay)
                        *delay = (int)(data->probedelay - timenow);
                else    *delay = 0;
        }
        *tA = (int)data->timeout_A;
        *tAAAA = (int)data->timeout_AAAA;
        *tother = (int)data->timeout_other;
        lock_rw_unlock(&e->lock);
        return ttl;
}

int 
infra_edns_update(struct infra_cache* infra, struct sockaddr_storage* addr,
        socklen_t addrlen, uint8_t* nm, size_t nmlen, int edns_version,
        time_t timenow)
{
        struct lruhash_entry* e = infra_lookup_nottl(infra, addr, addrlen,
                nm, nmlen, 1);
        struct infra_data* data;
        int needtoinsert = 0;
        if(!e) {
                if(!(e = new_entry(infra, addr, addrlen, nm, nmlen, timenow)))
                        return 0;
                needtoinsert = 1;
        } else if(((struct infra_data*)e->data)->ttl < timenow) {
                data_entry_init(infra, e, timenow);
        }
        /* have an entry, update the rtt, and the ttl */
        data = (struct infra_data*)e->data;
        /* do not update if noEDNS and stored is yesEDNS */
        if(!(edns_version == -1 && (data->edns_version != -1 &&
                data->edns_lame_known))) {
                data->edns_version = edns_version;
                data->edns_lame_known = 1;
        }

        if(needtoinsert)
                slabhash_insert(infra->hosts, e->hash, e, e->data, NULL);
        else    { lock_rw_unlock(&e->lock); }
        return 1;
}

int
infra_get_lame_rtt(struct infra_cache* infra,
        struct sockaddr_storage* addr, socklen_t addrlen,
        uint8_t* name, size_t namelen, uint16_t qtype, 
        int* lame, int* dnsseclame, int* reclame, int* rtt, time_t timenow)
{
        struct infra_data* host;
        struct lruhash_entry* e = infra_lookup_nottl(infra, addr, addrlen,
                name, namelen, 0);
        if(!e) 
                return 0;
        host = (struct infra_data*)e->data;
        *rtt = rtt_unclamped(&host->rtt);
        if(host->rtt.rto >= PROBE_MAXRTO && timenow >= host->probedelay
                && infra->infra_keep_probing) {
                /* single probe, keep probing */
                if(*rtt >= USEFUL_SERVER_TOP_TIMEOUT)
                        *rtt = still_useful_timeout();
        } else if(host->rtt.rto >= PROBE_MAXRTO && timenow < host->probedelay
                && rtt_notimeout(&host->rtt)*4 <= host->rtt.rto) {
                /* single probe for this domain, and we are not probing */
                /* unless the query type allows a probe to happen */
                if(qtype == LDNS_RR_TYPE_A) {
                        if(host->timeout_A >= TIMEOUT_COUNT_MAX)
                                *rtt = USEFUL_SERVER_TOP_TIMEOUT;
                        else    *rtt = still_useful_timeout();
                } else if(qtype == LDNS_RR_TYPE_AAAA) {
                        if(host->timeout_AAAA >= TIMEOUT_COUNT_MAX)
                                *rtt = USEFUL_SERVER_TOP_TIMEOUT;
                        else    *rtt = still_useful_timeout();
                } else {
                        if(host->timeout_other >= TIMEOUT_COUNT_MAX)
                                *rtt = USEFUL_SERVER_TOP_TIMEOUT;
                        else    *rtt = still_useful_timeout();
                }
        }
        /* expired entry */
        if(timenow > host->ttl) {
                /* see if this can be a re-probe of an unresponsive server */
                if(host->rtt.rto >= USEFUL_SERVER_TOP_TIMEOUT) {
                        lock_rw_unlock(&e->lock);
                        *rtt = still_useful_timeout();
                        *lame = 0;
                        *dnsseclame = 0;
                        *reclame = 0;
                        return 1;
                }
                lock_rw_unlock(&e->lock);
                return 0;
        }
        /* check lameness first */
        if(host->lame_type_A && qtype == LDNS_RR_TYPE_A) {
                lock_rw_unlock(&e->lock);
                *lame = 1;
                *dnsseclame = 0;
                *reclame = 0;
                return 1;
        } else if(host->lame_other && qtype != LDNS_RR_TYPE_A) {
                lock_rw_unlock(&e->lock);
                *lame = 1;
                *dnsseclame = 0;
                *reclame = 0;
                return 1;
        } else if(host->isdnsseclame) {
                lock_rw_unlock(&e->lock);
                *lame = 0;
                *dnsseclame = 1;
                *reclame = 0;
                return 1;
        } else if(host->rec_lame) {
                lock_rw_unlock(&e->lock);
                *lame = 0;
                *dnsseclame = 0;
                *reclame = 1;
                return 1;
        }
        /* no lameness for this type of query */
        lock_rw_unlock(&e->lock);
        *lame = 0;
        *dnsseclame = 0;
        *reclame = 0;
        return 1;
}

int infra_find_ratelimit(struct infra_cache* infra, uint8_t* name,
        size_t namelen)
{
        int labs = dname_count_labels(name);
        struct domain_limit_data* d = (struct domain_limit_data*)
                name_tree_lookup(&infra->domain_limits, name, namelen, labs,
                LDNS_RR_CLASS_IN);
        if(!d) return infra_dp_ratelimit;

        if(d->node.labs == labs && d->lim != -1)
                return d->lim; /* exact match */

        /* find 'below match' */
        if(d->node.labs == labs)
                d = (struct domain_limit_data*)d->node.parent;
        while(d) {
                if(d->below != -1)
                        return d->below;
                d = (struct domain_limit_data*)d->node.parent;
        }
        return infra_dp_ratelimit;
}

size_t ip_rate_sizefunc(void* k, void* ATTR_UNUSED(d))
{
        struct ip_rate_key* key = (struct ip_rate_key*)k;
        return sizeof(*key) + sizeof(struct ip_rate_data)
                + lock_get_mem(&key->entry.lock);
}

int ip_rate_compfunc(void* key1, void* key2)
{
        struct ip_rate_key* k1 = (struct ip_rate_key*)key1;
        struct ip_rate_key* k2 = (struct ip_rate_key*)key2;
        return sockaddr_cmp_addr(&k1->addr, k1->addrlen,
                &k2->addr, k2->addrlen);
}

void ip_rate_delkeyfunc(void* k, void* ATTR_UNUSED(arg))
{
        struct ip_rate_key* key = (struct ip_rate_key*)k;
        if(!key)
                return;
        lock_rw_destroy(&key->entry.lock);
        free(key);
}

/** find data item in array, for write access, caller unlocks */
static struct lruhash_entry* infra_find_ratedata(struct infra_cache* infra,
        uint8_t* name, size_t namelen, int wr)
{
        struct rate_key key;
        hashvalue_type h = dname_query_hash(name, 0xab);
        memset(&key, 0, sizeof(key));
        key.name = name;
        key.namelen = namelen;
        key.entry.hash = h;
        return slabhash_lookup(infra->domain_rates, h, &key, wr);
}

/** find data item in array for ip addresses */
static struct lruhash_entry* infra_find_ip_ratedata(struct infra_cache* infra,
        struct sockaddr_storage* addr, socklen_t addrlen, int wr)
{
        struct ip_rate_key key;
        hashvalue_type h = hash_addr(addr, addrlen, 0);
        memset(&key, 0, sizeof(key));
        key.addr = *addr;
        key.addrlen = addrlen;
        key.entry.hash = h;
        return slabhash_lookup(infra->client_ip_rates, h, &key, wr);
}

/** create rate data item for name, number 1 in now */
static void infra_create_ratedata(struct infra_cache* infra,
        uint8_t* name, size_t namelen, time_t timenow)
{
        hashvalue_type h = dname_query_hash(name, 0xab);
        struct rate_key* k = (struct rate_key*)calloc(1, sizeof(*k));
        struct rate_data* d = (struct rate_data*)calloc(1, sizeof(*d));
        if(!k || !d) {
                free(k);
                free(d);
                return; /* alloc failure */
        }
        k->namelen = namelen;
        k->name = memdup(name, namelen);
        if(!k->name) {
                free(k);
                free(d);
                return; /* alloc failure */
        }
        lock_rw_init(&k->entry.lock);
        k->entry.hash = h;
        k->entry.key = k;
        k->entry.data = d;
        d->qps[0] = 1;
        d->timestamp[0] = timenow;
        slabhash_insert(infra->domain_rates, h, &k->entry, d, NULL);
}

/** create rate data item for ip address */
static void infra_ip_create_ratedata(struct infra_cache* infra,
        struct sockaddr_storage* addr, socklen_t addrlen, time_t timenow,
        int mesh_wait)
{
        hashvalue_type h = hash_addr(addr, addrlen, 0);
        struct ip_rate_key* k = (struct ip_rate_key*)calloc(1, sizeof(*k));
        struct ip_rate_data* d = (struct ip_rate_data*)calloc(1, sizeof(*d));
        if(!k || !d) {
                free(k);
                free(d);
                return; /* alloc failure */
        }
        k->addr = *addr;
        k->addrlen = addrlen;
        lock_rw_init(&k->entry.lock);
        k->entry.hash = h;
        k->entry.key = k;
        k->entry.data = d;
        d->qps[0] = 1;
        d->timestamp[0] = timenow;
        d->mesh_wait = mesh_wait;
        slabhash_insert(infra->client_ip_rates, h, &k->entry, d, NULL);
}

/** Find the second and return its rate counter. If none and should_add, remove
 *  oldest to accommodate. Else return none. */
static int* infra_rate_find_second_or_none(void* data, time_t t, int should_add)
{
        struct rate_data* d = (struct rate_data*)data;
        int i, oldest;
        for(i=0; i<RATE_WINDOW; i++) {
                if(d->timestamp[i] == t)
                        return &(d->qps[i]);
        }
        if(!should_add) return NULL;
        /* remove oldest timestamp, and insert it at t with 0 qps */
        oldest = 0;
        for(i=0; i<RATE_WINDOW; i++) {
                if(d->timestamp[i] < d->timestamp[oldest])
                        oldest = i;
        }
        d->timestamp[oldest] = t;
        d->qps[oldest] = 0;
        return &(d->qps[oldest]);
}

/** find the second and return its rate counter, if none, remove oldest to
 *  accommodate */
static int* infra_rate_give_second(void* data, time_t t)
{
    return infra_rate_find_second_or_none(data, t, 1);
}

/** find the second and return its rate counter only if it exists. Caller
 *  should check for NULL return value */
static int* infra_rate_get_second(void* data, time_t t)
{
    return infra_rate_find_second_or_none(data, t, 0);
}

int infra_rate_max(void* data, time_t now, int backoff)
{
        struct rate_data* d = (struct rate_data*)data;
        int i, max = 0;
        for(i=0; i<RATE_WINDOW; i++) {
                if(backoff) {
                        if(now-d->timestamp[i] <= RATE_WINDOW &&
                                d->qps[i] > max) {
                                max = d->qps[i];
                        }
                } else {
                        if(now == d->timestamp[i]) {
                                return d->qps[i];
                        }
                }
        }
        return max;
}

int infra_ratelimit_inc(struct infra_cache* infra, uint8_t* name,
        size_t namelen, time_t timenow, int backoff, struct query_info* qinfo,
        struct comm_reply* replylist)
{
        int lim, max;
        struct lruhash_entry* entry;

        if(!infra_dp_ratelimit)
                return 1; /* not enabled */

        /* find ratelimit */
        lim = infra_find_ratelimit(infra, name, namelen);
        if(!lim)
                return 1; /* disabled for this domain */
        
        /* find or insert ratedata */
        entry = infra_find_ratedata(infra, name, namelen, 1);
        if(entry) {
                int premax = infra_rate_max(entry->data, timenow, backoff);
                int* cur = infra_rate_give_second(entry->data, timenow);
                (*cur)++;
                max = infra_rate_max(entry->data, timenow, backoff);
                lock_rw_unlock(&entry->lock);

                if(premax <= lim && max > lim) {
                        char buf[LDNS_MAX_DOMAINLEN], qnm[LDNS_MAX_DOMAINLEN];
                        char ts[12], cs[12], ip[128];
                        dname_str(name, buf);
                        dname_str(qinfo->qname, qnm);
                        sldns_wire2str_type_buf(qinfo->qtype, ts, sizeof(ts));
                        sldns_wire2str_class_buf(qinfo->qclass, cs, sizeof(cs));
                        ip[0]=0;
                        if(replylist) {
                                addr_to_str((struct sockaddr_storage *)&replylist->remote_addr,
                                        replylist->remote_addrlen, ip, sizeof(ip));
                                verbose(VERB_OPS, "ratelimit exceeded %s %d query %s %s %s from %s", buf, lim, qnm, cs, ts, ip);
                        } else {
                                verbose(VERB_OPS, "ratelimit exceeded %s %d query %s %s %s", buf, lim, qnm, cs, ts);
                        }
                }
                return (max <= lim);
        }

        /* create */
        infra_create_ratedata(infra, name, namelen, timenow);
        return (1 <= lim);
}

void infra_ratelimit_dec(struct infra_cache* infra, uint8_t* name,
        size_t namelen, time_t timenow)
{
        struct lruhash_entry* entry;
        int* cur;
        if(!infra_dp_ratelimit)
                return; /* not enabled */
        entry = infra_find_ratedata(infra, name, namelen, 1);
        if(!entry) return; /* not cached */
        cur = infra_rate_get_second(entry->data, timenow);
        if(cur == NULL) {
                /* our timenow is not available anymore; nothing to decrease */
                lock_rw_unlock(&entry->lock);
                return;
        }
        if((*cur) > 0)
                (*cur)--;
        lock_rw_unlock(&entry->lock);
}

int infra_ratelimit_exceeded(struct infra_cache* infra, uint8_t* name,
        size_t namelen, time_t timenow, int backoff)
{
        struct lruhash_entry* entry;
        int lim, max;
        if(!infra_dp_ratelimit)
                return 0; /* not enabled */

        /* find ratelimit */
        lim = infra_find_ratelimit(infra, name, namelen);
        if(!lim)
                return 0; /* disabled for this domain */

        /* find current rate */
        entry = infra_find_ratedata(infra, name, namelen, 0);
        if(!entry)
                return 0; /* not cached */
        max = infra_rate_max(entry->data, timenow, backoff);
        lock_rw_unlock(&entry->lock);

        return (max > lim);
}

size_t 
infra_get_mem(struct infra_cache* infra)
{
        size_t s = sizeof(*infra) + slabhash_get_mem(infra->hosts);
        if(infra->domain_rates) s += slabhash_get_mem(infra->domain_rates);
        if(infra->client_ip_rates) s += slabhash_get_mem(infra->client_ip_rates);
        /* ignore domain_limits because walk through tree is big */
        return s;
}

/* Returns 1 if the limit has not been exceeded, 0 otherwise. */
static int
check_ip_ratelimit(struct sockaddr_storage* addr, socklen_t addrlen,
        struct sldns_buffer* buffer, int premax, int max, int has_cookie)
{
        int limit;

        if(has_cookie) limit = infra_ip_ratelimit_cookie;
        else           limit = infra_ip_ratelimit;

        /* Disabled */
        if(limit == 0) return 1;

        if(premax <= limit && max > limit) {
                char client_ip[128], qnm[LDNS_MAX_DOMAINLEN+1+12+12];
                addr_to_str(addr, addrlen, client_ip, sizeof(client_ip));
                qnm[0]=0;
                if(sldns_buffer_limit(buffer)>LDNS_HEADER_SIZE &&
                        LDNS_QDCOUNT(sldns_buffer_begin(buffer))!=0) {
                        (void)sldns_wire2str_rrquestion_buf(
                                sldns_buffer_at(buffer, LDNS_HEADER_SIZE),
                                sldns_buffer_limit(buffer)-LDNS_HEADER_SIZE,
                                qnm, sizeof(qnm));
                        if(strlen(qnm)>0 && qnm[strlen(qnm)-1]=='\n')
                                qnm[strlen(qnm)-1] = 0; /*remove newline*/
                        if(strchr(qnm, '\t'))
                                *strchr(qnm, '\t') = ' ';
                        if(strchr(qnm, '\t'))
                                *strchr(qnm, '\t') = ' ';
                        verbose(VERB_OPS, "ip_ratelimit exceeded %s %d%s %s",
                                client_ip, limit,
                                has_cookie?"(cookie)":"", qnm);
                } else {
                        verbose(VERB_OPS, "ip_ratelimit exceeded %s %d%s (no query name)",
                                client_ip, limit,
                                has_cookie?"(cookie)":"");
                }
        }
        return (max <= limit);
}

int infra_ip_ratelimit_inc(struct infra_cache* infra,
        struct sockaddr_storage* addr, socklen_t addrlen, time_t timenow,
        int has_cookie, int backoff, struct sldns_buffer* buffer)
{
        int max;
        struct lruhash_entry* entry;

        /* not enabled */
        if(!infra_ip_ratelimit) {
                return 1;
        }
        /* find or insert ratedata */
        entry = infra_find_ip_ratedata(infra, addr, addrlen, 1);
        if(entry) {
                int premax = infra_rate_max(entry->data, timenow, backoff);
                int* cur = infra_rate_give_second(entry->data, timenow);
                (*cur)++;
                max = infra_rate_max(entry->data, timenow, backoff);
                lock_rw_unlock(&entry->lock);
                return check_ip_ratelimit(addr, addrlen, buffer, premax, max,
                        has_cookie);
        }

        /* create */
        infra_ip_create_ratedata(infra, addr, addrlen, timenow, 0);
        return 1;
}

int infra_wait_limit_allowed(struct infra_cache* infra, struct comm_reply* rep,
        int cookie_valid, struct config_file* cfg)
{
        struct lruhash_entry* entry;
        if(cfg->wait_limit == 0)
                return 1;

        entry = infra_find_ip_ratedata(infra, &rep->client_addr,
                rep->client_addrlen, 0);
        if(entry) {
                rbtree_type* tree;
                struct wait_limit_netblock_info* w;
                struct rate_data* d = (struct rate_data*)entry->data;
                int mesh_wait = d->mesh_wait;
                lock_rw_unlock(&entry->lock);

                /* have the wait amount, check how much is allowed */
                if(cookie_valid)
                        tree = &infra->wait_limits_cookie_netblock;
                else    tree = &infra->wait_limits_netblock;
                w = (struct wait_limit_netblock_info*)addr_tree_lookup(tree,
                        &rep->client_addr, rep->client_addrlen);
                if(w) {
                        if(w->limit != -1 && mesh_wait > w->limit)
                                return 0;
                } else {
                        /* if there is no IP netblock specific information,
                         * use the configured value. */
                        if(mesh_wait > (cookie_valid?cfg->wait_limit_cookie:
                                cfg->wait_limit))
                                return 0;
                }
        }
        return 1;
}

void infra_wait_limit_inc(struct infra_cache* infra, struct comm_reply* rep,
        time_t timenow, struct config_file* cfg)
{
        struct lruhash_entry* entry;
        if(cfg->wait_limit == 0)
                return;

        /* Find it */
        entry = infra_find_ip_ratedata(infra, &rep->client_addr,
                rep->client_addrlen, 1);
        if(entry) {
                struct rate_data* d = (struct rate_data*)entry->data;
                d->mesh_wait++;
                lock_rw_unlock(&entry->lock);
                return;
        }

        /* Create it */
        infra_ip_create_ratedata(infra, &rep->client_addr,
                rep->client_addrlen, timenow, 1);
}

void infra_wait_limit_dec(struct infra_cache* infra, struct comm_reply* rep,
        struct config_file* cfg)
{
        struct lruhash_entry* entry;
        if(cfg->wait_limit == 0)
                return;

        entry = infra_find_ip_ratedata(infra, &rep->client_addr,
                rep->client_addrlen, 1);
        if(entry) {
                struct rate_data* d = (struct rate_data*)entry->data;
                if(d->mesh_wait > 0)
                        d->mesh_wait--;
                lock_rw_unlock(&entry->lock);
        }
}