lib/dns/peer.c

	peer.c revision 0c27b3fe77ac1d5094ba3521e8142d9e7973133f
/*
 * Copyright (C) 2000, 2001, 2003-2009, 2012-2016  Internet Systems Consortium, Inc. ("ISC")
 *
 * This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/.
 */

/* $Id: peer.c,v 1.33 2009/09/02 23:48:02 tbox Exp $ */

/*! \file */

#include <config.h>

#include <isc/mem.h>
#include <isc/string.h>
#include <isc/util.h>
#include <isc/sockaddr.h>

#include <dns/bit.h>
#include <dns/fixedname.h>
#include <dns/name.h>
#include <dns/peer.h>

/*%
 * Bit positions in the dns_peer_t structure flags field
 */
#define BOGUS_BIT            0
#define SERVER_TRANSFER_FORMAT_BIT   1
#define TRANSFERS_BIT            2
#define PROVIDE_IXFR_BIT         3
#define REQUEST_IXFR_BIT         4
#define SUPPORT_EDNS_BIT         5
#define SERVER_UDPSIZE_BIT       6
#define SERVER_MAXUDP_BIT        7
#define REQUEST_NSID_BIT                 8
#define SEND_COOKIE_BIT                  9
#define NOTIFY_DSCP_BIT                 10
#define TRANSFER_DSCP_BIT               11
#define QUERY_DSCP_BIT                  12
#define REQUEST_EXPIRE_BIT              13
#define EDNS_VERSION_BIT            14
#define FORCE_TCP_BIT           15

static void
peerlist_delete(dns_peerlist_t **list);

static void
peer_delete(dns_peer_t **peer);

isc_result_t
dns_peerlist_new(isc_mem_t *mem, dns_peerlist_t **list) {
    dns_peerlist_t *l;

    REQUIRE(list != NULL);

    l = isc_mem_get(mem, sizeof(*l));
    if (l == NULL)
        return (ISC_R_NOMEMORY);

    ISC_LIST_INIT(l->elements);
    l->mem = mem;
    l->refs = 1;
    l->magic = DNS_PEERLIST_MAGIC;

    *list = l;

    return (ISC_R_SUCCESS);
}

void
dns_peerlist_attach(dns_peerlist_t *source, dns_peerlist_t **target) {
    REQUIRE(DNS_PEERLIST_VALID(source));
    REQUIRE(target != NULL);
    REQUIRE(*target == NULL);

    source->refs++;

    ENSURE(source->refs != 0xffffffffU);

    *target = source;
}

void
dns_peerlist_detach(dns_peerlist_t **list) {
    dns_peerlist_t *plist;

    REQUIRE(list != NULL);
    REQUIRE(*list != NULL);
    REQUIRE(DNS_PEERLIST_VALID(*list));

    plist = *list;
    *list = NULL;

    REQUIRE(plist->refs > 0);

    plist->refs--;

    if (plist->refs == 0)
        peerlist_delete(&plist);
}

static void
peerlist_delete(dns_peerlist_t **list) {
    dns_peerlist_t *l;
    dns_peer_t *server, *stmp;

    REQUIRE(list != NULL);
    REQUIRE(DNS_PEERLIST_VALID(*list));

    l = *list;

    REQUIRE(l->refs == 0);

    server = ISC_LIST_HEAD(l->elements);
    while (server != NULL) {
        stmp = ISC_LIST_NEXT(server, next);
        ISC_LIST_UNLINK(l->elements, server, next);
        dns_peer_detach(&server);
        server = stmp;
    }

    l->magic = 0;
    isc_mem_put(l->mem, l, sizeof(*l));

    *list = NULL;
}

void
dns_peerlist_addpeer(dns_peerlist_t *peers, dns_peer_t *peer) {
    dns_peer_t *p = NULL;

    dns_peer_attach(peer, &p);

    /*
     * More specifics to front of list.
     */
    for (p = ISC_LIST_HEAD(peers->elements);
         p != NULL;
         p = ISC_LIST_NEXT(p, next))
        if (p->prefixlen < peer->prefixlen)
            break;

    if (p != NULL)
        ISC_LIST_INSERTBEFORE(peers->elements, p, peer, next);
    else
        ISC_LIST_APPEND(peers->elements, peer, next);

}

isc_result_t
dns_peerlist_peerbyaddr(dns_peerlist_t *servers,
            isc_netaddr_t *addr, dns_peer_t **retval)
{
    dns_peer_t *server;
    isc_result_t res;

    REQUIRE(retval != NULL);
    REQUIRE(DNS_PEERLIST_VALID(servers));

    server = ISC_LIST_HEAD(servers->elements);
    while (server != NULL) {
        if (isc_netaddr_eqprefix(addr, &server->address,
                     server->prefixlen))
            break;

        server = ISC_LIST_NEXT(server, next);
    }

    if (server != NULL) {
        *retval = server;
        res = ISC_R_SUCCESS;
    } else {
        res = ISC_R_NOTFOUND;
    }

    return (res);
}


isc_result_t
dns_peerlist_currpeer(dns_peerlist_t *peers, dns_peer_t **retval) {
    dns_peer_t *p = NULL;

    p = ISC_LIST_TAIL(peers->elements);

    dns_peer_attach(p, retval);

    return (ISC_R_SUCCESS);
}

isc_result_t
dns_peer_new(isc_mem_t *mem, isc_netaddr_t *addr, dns_peer_t **peerptr) {
    unsigned int prefixlen = 0;

    REQUIRE(peerptr != NULL);
    switch(addr->family) {
    case AF_INET:
        prefixlen = 32;
        break;
    case AF_INET6:
         prefixlen = 128;
        break;
    default:
        INSIST(0);
    }

    return (dns_peer_newprefix(mem, addr, prefixlen, peerptr));
}

isc_result_t
dns_peer_newprefix(isc_mem_t *mem, isc_netaddr_t *addr, unsigned int prefixlen,
           dns_peer_t **peerptr)
{
    dns_peer_t *peer;

    REQUIRE(peerptr != NULL);

    peer = isc_mem_get(mem, sizeof(*peer));
    if (peer == NULL)
        return (ISC_R_NOMEMORY);

    peer->magic = DNS_PEER_MAGIC;
    peer->address = *addr;
    peer->prefixlen = prefixlen;
    peer->mem = mem;
    peer->bogus = ISC_FALSE;
    peer->transfer_format = dns_one_answer;
    peer->transfers = 0;
    peer->request_ixfr = ISC_FALSE;
    peer->provide_ixfr = ISC_FALSE;
    peer->key = NULL;
    peer->refs = 1;
    peer->transfer_source = NULL;
    peer->notify_source = NULL;
    peer->query_source = NULL;

    memset(&peer->bitflags, 0x0, sizeof(peer->bitflags));

    ISC_LINK_INIT(peer, next);

    *peerptr = peer;

    return (ISC_R_SUCCESS);
}

void
dns_peer_attach(dns_peer_t *source, dns_peer_t **target) {
    REQUIRE(DNS_PEER_VALID(source));
    REQUIRE(target != NULL);
    REQUIRE(*target == NULL);

    source->refs++;

    ENSURE(source->refs != 0xffffffffU);

    *target = source;
}

void
dns_peer_detach(dns_peer_t **peer) {
    dns_peer_t *p;

    REQUIRE(peer != NULL);
    REQUIRE(*peer != NULL);
    REQUIRE(DNS_PEER_VALID(*peer));

    p = *peer;

    REQUIRE(p->refs > 0);

    *peer = NULL;
    p->refs--;

    if (p->refs == 0)
        peer_delete(&p);
}

static void
peer_delete(dns_peer_t **peer) {
    dns_peer_t *p;
    isc_mem_t *mem;

    REQUIRE(peer != NULL);
    REQUIRE(DNS_PEER_VALID(*peer));

    p = *peer;

    REQUIRE(p->refs == 0);

    mem = p->mem;
    p->mem = NULL;
    p->magic = 0;

    if (p->key != NULL) {
        dns_name_free(p->key, mem);
        isc_mem_put(mem, p->key, sizeof(dns_name_t));
    }

    if (p->query_source != NULL)
        isc_mem_put(mem, p->query_source, sizeof(*p->query_source));

    if (p->notify_source != NULL)
        isc_mem_put(mem, p->notify_source, sizeof(*p->notify_source));

    if (p->transfer_source != NULL)
        isc_mem_put(mem, p->transfer_source,
                sizeof(*p->transfer_source));

    isc_mem_put(mem, p, sizeof(*p));

    *peer = NULL;
}

isc_result_t
dns_peer_setbogus(dns_peer_t *peer, isc_boolean_t newval) {
    isc_boolean_t existed;

    REQUIRE(DNS_PEER_VALID(peer));

    existed = DNS_BIT_CHECK(BOGUS_BIT, &peer->bitflags);

    peer->bogus = newval;
    DNS_BIT_SET(BOGUS_BIT, &peer->bitflags);

    return (existed ? ISC_R_EXISTS : ISC_R_SUCCESS);
}

isc_result_t
dns_peer_getbogus(dns_peer_t *peer, isc_boolean_t *retval) {
    REQUIRE(DNS_PEER_VALID(peer));
    REQUIRE(retval != NULL);

    if (DNS_BIT_CHECK(BOGUS_BIT, &peer->bitflags)) {
        *retval = peer->bogus;
        return (ISC_R_SUCCESS);
    } else
        return (ISC_R_NOTFOUND);
}


isc_result_t
dns_peer_setprovideixfr(dns_peer_t *peer, isc_boolean_t newval) {
    isc_boolean_t existed;

    REQUIRE(DNS_PEER_VALID(peer));

    existed = DNS_BIT_CHECK(PROVIDE_IXFR_BIT, &peer->bitflags);

    peer->provide_ixfr = newval;
    DNS_BIT_SET(PROVIDE_IXFR_BIT, &peer->bitflags);

    return (existed ? ISC_R_EXISTS : ISC_R_SUCCESS);
}

isc_result_t
dns_peer_getprovideixfr(dns_peer_t *peer, isc_boolean_t *retval) {
    REQUIRE(DNS_PEER_VALID(peer));
    REQUIRE(retval != NULL);

    if (DNS_BIT_CHECK(PROVIDE_IXFR_BIT, &peer->bitflags)) {
        *retval = peer->provide_ixfr;
        return (ISC_R_SUCCESS);
    } else {
        return (ISC_R_NOTFOUND);
    }
}

isc_result_t
dns_peer_setrequestixfr(dns_peer_t *peer, isc_boolean_t newval) {
    isc_boolean_t existed;

    REQUIRE(DNS_PEER_VALID(peer));

    existed = DNS_BIT_CHECK(REQUEST_IXFR_BIT, &peer->bitflags);

    peer->request_ixfr = newval;
    DNS_BIT_SET(REQUEST_IXFR_BIT, &peer->bitflags);

    return (existed ? ISC_R_EXISTS : ISC_R_SUCCESS);
}

isc_result_t
dns_peer_getrequestixfr(dns_peer_t *peer, isc_boolean_t *retval) {
    REQUIRE(DNS_PEER_VALID(peer));
    REQUIRE(retval != NULL);

    if (DNS_BIT_CHECK(REQUEST_IXFR_BIT, &peer->bitflags)) {
        *retval = peer->request_ixfr;
        return (ISC_R_SUCCESS);
    } else
        return (ISC_R_NOTFOUND);
}

isc_result_t
dns_peer_setsupportedns(dns_peer_t *peer, isc_boolean_t newval) {
    isc_boolean_t existed;

    REQUIRE(DNS_PEER_VALID(peer));

    existed = DNS_BIT_CHECK(SUPPORT_EDNS_BIT, &peer->bitflags);

    peer->support_edns = newval;
    DNS_BIT_SET(SUPPORT_EDNS_BIT, &peer->bitflags);

    return (existed ? ISC_R_EXISTS : ISC_R_SUCCESS);
}

isc_result_t
dns_peer_getsupportedns(dns_peer_t *peer, isc_boolean_t *retval) {
    REQUIRE(DNS_PEER_VALID(peer));
    REQUIRE(retval != NULL);

    if (DNS_BIT_CHECK(SUPPORT_EDNS_BIT, &peer->bitflags)) {
        *retval = peer->support_edns;
        return (ISC_R_SUCCESS);
    } else
        return (ISC_R_NOTFOUND);
}

isc_result_t
dns_peer_setrequestnsid(dns_peer_t *peer, isc_boolean_t newval) {
    isc_boolean_t existed;

    REQUIRE(DNS_PEER_VALID(peer));

    existed = DNS_BIT_CHECK(REQUEST_NSID_BIT, &peer->bitflags);

    peer->request_nsid = newval;
    DNS_BIT_SET(REQUEST_NSID_BIT, &peer->bitflags);

    return (existed ? ISC_R_EXISTS : ISC_R_SUCCESS);
}

isc_result_t
dns_peer_getrequestnsid(dns_peer_t *peer, isc_boolean_t *retval) {
    REQUIRE(DNS_PEER_VALID(peer));
    REQUIRE(retval != NULL);

    if (DNS_BIT_CHECK(REQUEST_NSID_BIT, &peer->bitflags)) {
        *retval = peer->request_nsid;
        return (ISC_R_SUCCESS);
    } else
        return (ISC_R_NOTFOUND);
}

isc_result_t
dns_peer_setsendcookie(dns_peer_t *peer, isc_boolean_t newval) {
    isc_boolean_t existed;

    REQUIRE(DNS_PEER_VALID(peer));

    existed = DNS_BIT_CHECK(SEND_COOKIE_BIT, &peer->bitflags);

    peer->send_cookie = newval;
    DNS_BIT_SET(SEND_COOKIE_BIT, &peer->bitflags);

    return (existed ? ISC_R_EXISTS : ISC_R_SUCCESS);
}

isc_result_t
dns_peer_getsendcookie(dns_peer_t *peer, isc_boolean_t *retval) {
    REQUIRE(DNS_PEER_VALID(peer));
    REQUIRE(retval != NULL);

    if (DNS_BIT_CHECK(SEND_COOKIE_BIT, &peer->bitflags)) {
        *retval = peer->send_cookie;
        return (ISC_R_SUCCESS);
    } else
        return (ISC_R_NOTFOUND);
}

isc_result_t
dns_peer_setrequestexpire(dns_peer_t *peer, isc_boolean_t newval) {
    isc_boolean_t existed;

    REQUIRE(DNS_PEER_VALID(peer));

    existed = DNS_BIT_CHECK(REQUEST_EXPIRE_BIT, &peer->bitflags);

    peer->request_expire = newval;
    DNS_BIT_SET(REQUEST_EXPIRE_BIT, &peer->bitflags);

    return (existed ? ISC_R_EXISTS : ISC_R_SUCCESS);
}

isc_result_t
dns_peer_getrequestexpire(dns_peer_t *peer, isc_boolean_t *retval) {
    REQUIRE(DNS_PEER_VALID(peer));
    REQUIRE(retval != NULL);

    if (DNS_BIT_CHECK(REQUEST_EXPIRE_BIT, &peer->bitflags)) {
        *retval = peer->request_expire;
        return (ISC_R_SUCCESS);
    } else
        return (ISC_R_NOTFOUND);
}

isc_result_t
dns_peer_setforcetcp(dns_peer_t *peer, isc_boolean_t newval) {
    isc_boolean_t existed;

    REQUIRE(DNS_PEER_VALID(peer));

    existed = DNS_BIT_CHECK(FORCE_TCP_BIT, &peer->bitflags);

    peer->force_tcp = newval;
    DNS_BIT_SET(FORCE_TCP_BIT, &peer->bitflags);

    return (existed ? ISC_R_EXISTS : ISC_R_SUCCESS);
}

isc_result_t
dns_peer_getforcetcp(dns_peer_t *peer, isc_boolean_t *retval) {
    REQUIRE(DNS_PEER_VALID(peer));
    REQUIRE(retval != NULL);

    if (DNS_BIT_CHECK(FORCE_TCP_BIT, &peer->bitflags)) {
        *retval = peer->force_tcp;
        return (ISC_R_SUCCESS);
    } else
        return (ISC_R_NOTFOUND);
}

isc_result_t
dns_peer_settransfers(dns_peer_t *peer, isc_uint32_t newval) {
    isc_boolean_t existed;

    REQUIRE(DNS_PEER_VALID(peer));

    existed = DNS_BIT_CHECK(TRANSFERS_BIT, &peer->bitflags);

    peer->transfers = newval;
    DNS_BIT_SET(TRANSFERS_BIT, &peer->bitflags);

    return (existed ? ISC_R_EXISTS : ISC_R_SUCCESS);
}

isc_result_t
dns_peer_gettransfers(dns_peer_t *peer, isc_uint32_t *retval) {
    REQUIRE(DNS_PEER_VALID(peer));
    REQUIRE(retval != NULL);

    if (DNS_BIT_CHECK(TRANSFERS_BIT, &peer->bitflags)) {
        *retval = peer->transfers;
        return (ISC_R_SUCCESS);
    } else {
        return (ISC_R_NOTFOUND);
    }
}

isc_result_t
dns_peer_settransferformat(dns_peer_t *peer, dns_transfer_format_t newval) {
    isc_boolean_t existed;

    REQUIRE(DNS_PEER_VALID(peer));

    existed = DNS_BIT_CHECK(SERVER_TRANSFER_FORMAT_BIT,
                 &peer->bitflags);

    peer->transfer_format = newval;
    DNS_BIT_SET(SERVER_TRANSFER_FORMAT_BIT, &peer->bitflags);

    return (existed ? ISC_R_EXISTS : ISC_R_SUCCESS);
}

isc_result_t
dns_peer_gettransferformat(dns_peer_t *peer, dns_transfer_format_t *retval) {
    REQUIRE(DNS_PEER_VALID(peer));
    REQUIRE(retval != NULL);

    if (DNS_BIT_CHECK(SERVER_TRANSFER_FORMAT_BIT, &peer->bitflags)) {
        *retval = peer->transfer_format;
        return (ISC_R_SUCCESS);
    } else {
        return (ISC_R_NOTFOUND);
    }
}

isc_result_t
dns_peer_getkey(dns_peer_t *peer, dns_name_t **retval) {
    REQUIRE(DNS_PEER_VALID(peer));
    REQUIRE(retval != NULL);

    if (peer->key != NULL) {
        *retval = peer->key;
    }

    return (peer->key == NULL ? ISC_R_NOTFOUND : ISC_R_SUCCESS);
}

isc_result_t
dns_peer_setkey(dns_peer_t *peer, dns_name_t **keyval) {
    isc_boolean_t exists = ISC_FALSE;

    if (peer->key != NULL) {
        dns_name_free(peer->key, peer->mem);
        isc_mem_put(peer->mem, peer->key, sizeof(dns_name_t));
        exists = ISC_TRUE;
    }

    peer->key = *keyval;
    *keyval = NULL;

    return (exists ? ISC_R_EXISTS : ISC_R_SUCCESS);
}

isc_result_t
dns_peer_setkeybycharp(dns_peer_t *peer, const char *keyval) {
    isc_buffer_t b;
    dns_fixedname_t fname;
    dns_name_t *name;
    isc_result_t result;

    dns_fixedname_init(&fname);
    isc_buffer_constinit(&b, keyval, strlen(keyval));
    isc_buffer_add(&b, strlen(keyval));
    result = dns_name_fromtext(dns_fixedname_name(&fname), &b,
                   dns_rootname, 0, NULL);
    if (result != ISC_R_SUCCESS)
        return (result);

    name = isc_mem_get(peer->mem, sizeof(dns_name_t));
    if (name == NULL)
        return (ISC_R_NOMEMORY);

    dns_name_init(name, NULL);
    result = dns_name_dup(dns_fixedname_name(&fname), peer->mem, name);
    if (result != ISC_R_SUCCESS) {
        isc_mem_put(peer->mem, name, sizeof(dns_name_t));
        return (result);
    }

    result = dns_peer_setkey(peer, &name);
    if (result != ISC_R_SUCCESS)
        isc_mem_put(peer->mem, name, sizeof(dns_name_t));

    return (result);
}

isc_result_t
dns_peer_settransfersource(dns_peer_t *peer,
               const isc_sockaddr_t *transfer_source)
{
    REQUIRE(DNS_PEER_VALID(peer));

    if (peer->transfer_source != NULL) {
        isc_mem_put(peer->mem, peer->transfer_source,
                sizeof(*peer->transfer_source));
        peer->transfer_source = NULL;
    }
    if (transfer_source != NULL) {
        peer->transfer_source = isc_mem_get(peer->mem,
                        sizeof(*peer->transfer_source));
        if (peer->transfer_source == NULL)
            return (ISC_R_NOMEMORY);

        *peer->transfer_source = *transfer_source;
    }
    return (ISC_R_SUCCESS);
}

isc_result_t
dns_peer_gettransfersource(dns_peer_t *peer, isc_sockaddr_t *transfer_source) {
    REQUIRE(DNS_PEER_VALID(peer));
    REQUIRE(transfer_source != NULL);

    if (peer->transfer_source == NULL)
        return (ISC_R_NOTFOUND);
    *transfer_source = *peer->transfer_source;
    return (ISC_R_SUCCESS);
}

isc_result_t
dns_peer_setnotifysource(dns_peer_t *peer,
             const isc_sockaddr_t *notify_source)
{
    REQUIRE(DNS_PEER_VALID(peer));

    if (peer->notify_source != NULL) {
        isc_mem_put(peer->mem, peer->notify_source,
                sizeof(*peer->notify_source));
        peer->notify_source = NULL;
    }
    if (notify_source != NULL) {
        peer->notify_source = isc_mem_get(peer->mem,
                        sizeof(*peer->notify_source));
        if (peer->notify_source == NULL)
            return (ISC_R_NOMEMORY);

        *peer->notify_source = *notify_source;
    }
    return (ISC_R_SUCCESS);
}

isc_result_t
dns_peer_getnotifysource(dns_peer_t *peer, isc_sockaddr_t *notify_source) {
    REQUIRE(DNS_PEER_VALID(peer));
    REQUIRE(notify_source != NULL);

    if (peer->notify_source == NULL)
        return (ISC_R_NOTFOUND);
    *notify_source = *peer->notify_source;
    return (ISC_R_SUCCESS);
}

isc_result_t
dns_peer_setquerysource(dns_peer_t *peer, const isc_sockaddr_t *query_source) {
    REQUIRE(DNS_PEER_VALID(peer));

    if (peer->query_source != NULL) {
        isc_mem_put(peer->mem, peer->query_source,
                sizeof(*peer->query_source));
        peer->query_source = NULL;
    }
    if (query_source != NULL) {
        peer->query_source = isc_mem_get(peer->mem,
                        sizeof(*peer->query_source));
        if (peer->query_source == NULL)
            return (ISC_R_NOMEMORY);

        *peer->query_source = *query_source;
    }
    return (ISC_R_SUCCESS);
}

isc_result_t
dns_peer_getquerysource(dns_peer_t *peer, isc_sockaddr_t *query_source) {
    REQUIRE(DNS_PEER_VALID(peer));
    REQUIRE(query_source != NULL);

    if (peer->query_source == NULL)
        return (ISC_R_NOTFOUND);
    *query_source = *peer->query_source;
    return (ISC_R_SUCCESS);
}

isc_result_t
dns_peer_setudpsize(dns_peer_t *peer, isc_uint16_t udpsize) {
    isc_boolean_t existed;

    REQUIRE(DNS_PEER_VALID(peer));

    existed = DNS_BIT_CHECK(SERVER_UDPSIZE_BIT, &peer->bitflags);

    peer->udpsize = udpsize;
    DNS_BIT_SET(SERVER_UDPSIZE_BIT, &peer->bitflags);

    return (existed ? ISC_R_EXISTS : ISC_R_SUCCESS);
}

isc_result_t
dns_peer_getudpsize(dns_peer_t *peer, isc_uint16_t *udpsize) {

    REQUIRE(DNS_PEER_VALID(peer));
    REQUIRE(udpsize != NULL);

    if (DNS_BIT_CHECK(SERVER_UDPSIZE_BIT, &peer->bitflags)) {
        *udpsize = peer->udpsize;
        return (ISC_R_SUCCESS);
    } else {
        return (ISC_R_NOTFOUND);
    }
}

isc_result_t
dns_peer_setmaxudp(dns_peer_t *peer, isc_uint16_t maxudp) {
    isc_boolean_t existed;

    REQUIRE(DNS_PEER_VALID(peer));

    existed = DNS_BIT_CHECK(SERVER_MAXUDP_BIT, &peer->bitflags);

    peer->maxudp = maxudp;
    DNS_BIT_SET(SERVER_MAXUDP_BIT, &peer->bitflags);

    return (existed ? ISC_R_EXISTS : ISC_R_SUCCESS);
}

isc_result_t
dns_peer_getmaxudp(dns_peer_t *peer, isc_uint16_t *maxudp) {

    REQUIRE(DNS_PEER_VALID(peer));
    REQUIRE(maxudp != NULL);

    if (DNS_BIT_CHECK(SERVER_MAXUDP_BIT, &peer->bitflags)) {
        *maxudp = peer->maxudp;
        return (ISC_R_SUCCESS);
    } else {
        return (ISC_R_NOTFOUND);
    }
}

isc_result_t
dns_peer_setnotifydscp(dns_peer_t *peer, isc_dscp_t dscp) {
    REQUIRE(DNS_PEER_VALID(peer));
    REQUIRE(dscp < 64);

    peer->notify_dscp = dscp;
    DNS_BIT_SET(NOTIFY_DSCP_BIT, &peer->bitflags);
    return (ISC_R_SUCCESS);
}

isc_result_t
dns_peer_getnotifydscp(dns_peer_t *peer, isc_dscp_t *dscpp) {
    REQUIRE(DNS_PEER_VALID(peer));
    REQUIRE(dscpp != NULL);

    if (DNS_BIT_CHECK(NOTIFY_DSCP_BIT, &peer->bitflags)) {
        *dscpp = peer->notify_dscp;
        return (ISC_R_SUCCESS);
    }
    return (ISC_R_NOTFOUND);
}

isc_result_t
dns_peer_settransferdscp(dns_peer_t *peer, isc_dscp_t dscp) {
    REQUIRE(DNS_PEER_VALID(peer));
    REQUIRE(dscp < 64);

    peer->transfer_dscp = dscp;
    DNS_BIT_SET(TRANSFER_DSCP_BIT, &peer->bitflags);
    return (ISC_R_SUCCESS);
}

isc_result_t
dns_peer_gettransferdscp(dns_peer_t *peer, isc_dscp_t *dscpp) {
    REQUIRE(DNS_PEER_VALID(peer));
    REQUIRE(dscpp != NULL);

    if (DNS_BIT_CHECK(TRANSFER_DSCP_BIT, &peer->bitflags)) {
        *dscpp = peer->transfer_dscp;
        return (ISC_R_SUCCESS);
    }
    return (ISC_R_NOTFOUND);
}

isc_result_t
dns_peer_setquerydscp(dns_peer_t *peer, isc_dscp_t dscp) {
    REQUIRE(DNS_PEER_VALID(peer));
    REQUIRE(dscp < 64);

    peer->query_dscp = dscp;
    DNS_BIT_SET(QUERY_DSCP_BIT, &peer->bitflags);
    return (ISC_R_SUCCESS);
}

isc_result_t
dns_peer_getquerydscp(dns_peer_t *peer, isc_dscp_t *dscpp) {
    REQUIRE(DNS_PEER_VALID(peer));
    REQUIRE(dscpp != NULL);

    if (DNS_BIT_CHECK(QUERY_DSCP_BIT, &peer->bitflags)) {
        *dscpp = peer->query_dscp;
        return (ISC_R_SUCCESS);
    }
    return (ISC_R_NOTFOUND);
}

isc_result_t
dns_peer_setednsversion(dns_peer_t *peer, isc_uint8_t ednsversion) {
    REQUIRE(DNS_PEER_VALID(peer));

    peer->ednsversion = ednsversion;
    DNS_BIT_SET(EDNS_VERSION_BIT, &peer->bitflags);

    return (ISC_R_SUCCESS);
}

isc_result_t
dns_peer_getednsversion(dns_peer_t *peer, isc_uint8_t *ednsversion) {
    REQUIRE(DNS_PEER_VALID(peer));
    REQUIRE(ednsversion != NULL);

    if (DNS_BIT_CHECK(EDNS_VERSION_BIT, &peer->bitflags)) {
        *ednsversion = peer->ednsversion;
        return (ISC_R_SUCCESS);
    } else
        return (ISC_R_NOTFOUND);
}