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|
/*
* xfrd.c - XFR (transfer) Daemon source file. Coordinates SOA updates.
*
* Copyright (c) 2001-2006, NLnet Labs. All rights reserved.
*
* See LICENSE for the license.
*
*/
#include <config.h>
#include <assert.h>
#include <string.h>
#include <unistd.h>
#include <stdlib.h>
#include <errno.h>
#include "xfrd.h"
#include "xfrd-tcp.h"
#include "xfrd-disk.h"
#include "xfrd-notify.h"
#include "options.h"
#include "util.h"
#include "netio.h"
#include "region-allocator.h"
#include "nsd.h"
#include "packet.h"
#include "difffile.h"
#include "ipc.h"
#define XFRD_TRANSFER_TIMEOUT_START 10 /* empty zone timeout is between x and 2*x seconds */
#define XFRD_TRANSFER_TIMEOUT_MAX 14400 /* empty zone timeout max expbackoff */
#define XFRD_UDP_TIMEOUT 10 /* seconds, before a udp request times out */
#define XFRD_NO_IXFR_CACHE 172800 /* 48h before retrying ixfr's after notimpl */
#define XFRD_LOWERBOUND_REFRESH 1 /* seconds, smallest refresh timeout */
#define XFRD_LOWERBOUND_RETRY 1 /* seconds, smallest retry timeout */
#define XFRD_MAX_ROUNDS 3 /* max number of rounds along the masters */
#define XFRD_TSIG_MAX_UNSIGNED 103 /* max number of packets without tsig in a tcp stream. */
/* rfc recommends 100, +3 for offbyone errors/interoperability. */
/* the daemon state */
xfrd_state_t* xfrd = 0;
/* main xfrd loop */
static void xfrd_main();
/* shut down xfrd, close sockets. */
static void xfrd_shutdown();
/* create zone rbtree at start */
static void xfrd_init_zones();
/* free up memory used by main database */
static void xfrd_free_namedb();
/* handle zone timeout, event */
static void xfrd_handle_zone(netio_type *netio,
netio_handler_type *handler, netio_event_types_type event_types);
/* handle incoming notification message. soa can be NULL. true if transfer needed. */
static int xfrd_handle_incoming_notify(xfrd_zone_t* zone, xfrd_soa_t* soa);
/* call with buffer just after the soa dname. returns 0 on error. */
static int xfrd_parse_soa_info(buffer_type* packet, xfrd_soa_t* soa);
/* set the zone state to a new state (takes care of expiry messages) */
static void xfrd_set_zone_state(xfrd_zone_t* zone, enum xfrd_zone_state new_zone_state);
/* set timer for retry amount (depends on zone_state) */
static void xfrd_set_timer_retry(xfrd_zone_t* zone);
/* set timer for refresh timeout (depends on zone_state) */
static void xfrd_set_timer_refresh(xfrd_zone_t* zone);
/* set reload timeout */
static void xfrd_set_reload_timeout();
/* handle reload timeout */
static void xfrd_handle_reload(netio_type *netio,
netio_handler_type *handler, netio_event_types_type event_types);
/* send expiry notifications to nsd */
static void xfrd_send_expire_notification(xfrd_zone_t* zone);
/* send ixfr request, returns fd of connection to read on */
static int xfrd_send_ixfr_request_udp(xfrd_zone_t* zone);
/* obtain udp socket slot */
static void xfrd_udp_obtain(xfrd_zone_t* zone);
/* read data via udp */
static void xfrd_udp_read(xfrd_zone_t* zone);
/* find master by notify number */
static int find_same_master_notify(xfrd_zone_t* zone, int acl_num_nfy);
void
xfrd_init(int socket, struct nsd* nsd)
{
region_type* region;
assert(xfrd == 0);
/* to setup signalhandling */
nsd->server_kind = NSD_SERVER_BOTH;
region = region_create(xalloc, free);
xfrd = (xfrd_state_t*)region_alloc(region, sizeof(xfrd_state_t));
memset(xfrd, 0, sizeof(xfrd_state_t));
xfrd->region = region;
xfrd->xfrd_start_time = time(0);
xfrd->netio = netio_create(xfrd->region);
xfrd->nsd = nsd;
xfrd->packet = buffer_create(xfrd->region, QIOBUFSZ);
xfrd->udp_waiting_first = NULL;
xfrd->udp_waiting_last = NULL;
xfrd->udp_use_num = 0;
xfrd->ipc_pass = buffer_create(xfrd->region, QIOBUFSZ);
xfrd->parent_soa_info_pass = 0;
/* add the handlers already, because this involves allocs */
xfrd->reload_handler.fd = -1;
xfrd->reload_handler.timeout = NULL;
xfrd->reload_handler.user_data = xfrd;
xfrd->reload_handler.event_types = NETIO_EVENT_TIMEOUT;
xfrd->reload_handler.event_handler = xfrd_handle_reload;
xfrd->reload_timeout.tv_sec = 0;
xfrd->reload_cmd_last_sent = xfrd->xfrd_start_time;
xfrd->can_send_reload = 1;
xfrd->ipc_send_blocked = 0;
xfrd->ipc_handler.fd = socket;
xfrd->ipc_handler.timeout = NULL;
xfrd->ipc_handler.user_data = xfrd;
xfrd->ipc_handler.event_types = NETIO_EVENT_READ;
xfrd->ipc_handler.event_handler = xfrd_handle_ipc;
xfrd->ipc_conn = xfrd_tcp_create(xfrd->region);
/* not reading using ipc_conn yet */
xfrd->ipc_conn->is_reading = 0;
xfrd->ipc_conn->fd = xfrd->ipc_handler.fd;
xfrd->ipc_conn_write = xfrd_tcp_create(xfrd->region);
xfrd->ipc_conn_write->fd = xfrd->ipc_handler.fd;
xfrd->need_to_send_reload = 0;
xfrd->sending_zone_state = 0;
xfrd->dirty_zones = stack_create(xfrd->region,
nsd_options_num_zones(nsd->options));
xfrd->notify_waiting_first = NULL;
xfrd->notify_waiting_last = NULL;
xfrd->notify_udp_num = 0;
xfrd->tcp_set = xfrd_tcp_set_create(xfrd->region);
xfrd->tcp_set->tcp_timeout = nsd->tcp_timeout;
srandom((unsigned long) getpid() * (unsigned long) time(NULL));
DEBUG(DEBUG_XFRD,1, (LOG_INFO, "xfrd pre-startup"));
diff_snip_garbage(nsd->db, nsd->options);
xfrd_init_zones();
xfrd_free_namedb();
xfrd_read_state(xfrd);
xfrd_send_expy_all_zones();
/* add handlers after zone handlers so they are before them in list */
netio_add_handler(xfrd->netio, &xfrd->reload_handler);
netio_add_handler(xfrd->netio, &xfrd->ipc_handler);
DEBUG(DEBUG_XFRD,1, (LOG_INFO, "xfrd startup"));
xfrd_main();
}
static void
xfrd_main()
{
xfrd->shutdown = 0;
while(!xfrd->shutdown)
{
/* dispatch may block for a longer period, so current is gone */
xfrd->got_time = 0;
if(netio_dispatch(xfrd->netio, NULL, 0) == -1) {
if (errno != EINTR) {
log_msg(LOG_ERR,
"xfrd netio_dispatch failed: %s",
strerror(errno));
}
}
if(xfrd->nsd->signal_hint_quit || xfrd->nsd->signal_hint_shutdown)
xfrd->shutdown = 1;
}
xfrd_shutdown();
}
static void
xfrd_shutdown()
{
xfrd_zone_t* zone;
int i;
DEBUG(DEBUG_XFRD,1, (LOG_INFO, "xfrd shutdown"));
xfrd_write_state(xfrd);
close(xfrd->ipc_handler.fd);
/* close tcp sockets */
for(i=0; i<XFRD_MAX_TCP; i++)
{
if(xfrd->tcp_set->tcp_state[i]->fd != -1) {
close(xfrd->tcp_set->tcp_state[i]->fd);
xfrd->tcp_set->tcp_state[i]->fd = -1;
}
}
/* close udp sockets */
RBTREE_FOR(zone, xfrd_zone_t*, xfrd->zones)
{
if(zone->tcp_conn==-1 && zone->zone_handler.fd != -1) {
close(zone->zone_handler.fd);
zone->zone_handler.fd = -1;
}
close_notify_fds(xfrd->notify_zones);
}
/* shouldn't we clean up memory used by xfrd process */
exit(0);
}
static void
xfrd_init_zones()
{
zone_type *dbzone;
zone_options_t *zone_opt;
xfrd_zone_t *xzone;
const dname_type* dname;
assert(xfrd->zones == 0);
assert(xfrd->nsd->db != 0);
xfrd->zones = rbtree_create(xfrd->region,
(int (*)(const void *, const void *)) dname_compare);
xfrd->notify_zones = rbtree_create(xfrd->region,
(int (*)(const void *, const void *)) dname_compare);
RBTREE_FOR(zone_opt, zone_options_t*, xfrd->nsd->options->zone_options)
{
DEBUG(DEBUG_XFRD,1, (LOG_INFO, "Zone %s\n", zone_opt->name));
dname = dname_parse(xfrd->region, zone_opt->name);
if(!dname) {
log_msg(LOG_ERR, "xfrd: Could not parse zone name %s.", zone_opt->name);
continue;
}
dbzone = domain_find_zone(domain_table_find(xfrd->nsd->db->domains, dname));
if(dbzone && dname_compare(dname, domain_dname(dbzone->apex)) != 0)
dbzone = 0; /* we found a parent zone */
DEBUG(DEBUG_XFRD,1, (LOG_INFO, "xfrd: adding %s zone %s\n",
dbzone?"filled":"empty", zone_opt->name));
init_notify_send(xfrd->notify_zones, xfrd->netio,
xfrd->region, dname, zone_opt, dbzone);
if(!zone_is_slave(zone_opt)) {
DEBUG(DEBUG_XFRD,1, (LOG_INFO, "xfrd: zone %s, master zone has no outgoing xfr requests", zone_opt->name));
continue;
}
xzone = (xfrd_zone_t*)region_alloc(xfrd->region, sizeof(xfrd_zone_t));
memset(xzone, 0, sizeof(xfrd_zone_t));
xzone->apex = dname;
xzone->apex_str = zone_opt->name;
xzone->state = xfrd_zone_refreshing;
xzone->dirty = 0;
xzone->zone_options = zone_opt;
/* first retry will use first master */
xzone->master = 0;
xzone->master_num = 0;
xzone->next_master = 0;
xzone->fresh_xfr_timeout = XFRD_TRANSFER_TIMEOUT_START;
xzone->soa_nsd_acquired = 0;
xzone->soa_disk_acquired = 0;
xzone->soa_notified_acquired = 0;
/* [0]=1, [1]=0; "." domain name */
xzone->soa_nsd.prim_ns[0] = 1;
xzone->soa_nsd.email[0] = 1;
xzone->soa_disk.prim_ns[0]=1;
xzone->soa_disk.email[0]=1;
xzone->soa_notified.prim_ns[0]=1;
xzone->soa_notified.email[0]=1;
xzone->zone_handler.fd = -1;
xzone->zone_handler.timeout = 0;
xzone->zone_handler.user_data = xzone;
xzone->zone_handler.event_types =
NETIO_EVENT_READ|NETIO_EVENT_TIMEOUT;
xzone->zone_handler.event_handler = xfrd_handle_zone;
netio_add_handler(xfrd->netio, &xzone->zone_handler);
xzone->tcp_conn = -1;
xzone->tcp_waiting = 0;
xzone->udp_waiting = 0;
tsig_create_record_custom(&xzone->tsig, xfrd->region, 0, 0, 4);
if(dbzone && dbzone->soa_rrset && dbzone->soa_rrset->rrs) {
xzone->soa_nsd_acquired = xfrd_time();
xzone->soa_disk_acquired = xfrd_time();
/* we only use the first SOA in the rrset */
xfrd_copy_soa(&xzone->soa_nsd, dbzone->soa_rrset->rrs);
xfrd_copy_soa(&xzone->soa_disk, dbzone->soa_rrset->rrs);
}
/* set refreshing anyway, we have data but it may be old */
xfrd_set_refresh_now(xzone);
xzone->node.key = dname;
rbtree_insert(xfrd->zones, (rbnode_t*)xzone);
}
DEBUG(DEBUG_XFRD,1, (LOG_INFO, "xfrd: started server %d secondary zones", (int)xfrd->zones->count));
}
void
xfrd_send_expy_all_zones()
{
xfrd_zone_t* zone;
RBTREE_FOR(zone, xfrd_zone_t*, xfrd->zones)
{
xfrd_send_expire_notification(zone);
}
}
void
xfrd_reopen_logfile()
{
if (xfrd->nsd->file_rotation_ok)
log_reopen(xfrd->nsd->log_filename, 0);
}
static void
xfrd_free_namedb()
{
namedb_close(xfrd->nsd->db);
xfrd->nsd->db = 0;
}
static void
xfrd_set_timer_refresh(xfrd_zone_t* zone)
{
time_t set_refresh;
time_t set_expire;
time_t set_min;
time_t set;
if(zone->soa_disk_acquired == 0 || zone->state != xfrd_zone_ok) {
xfrd_set_timer_retry(zone);
return;
}
/* refresh or expire timeout, whichever is earlier */
set_refresh = zone->soa_disk_acquired + ntohl(zone->soa_disk.refresh);
set_expire = zone->soa_disk_acquired + ntohl(zone->soa_disk.expire);
if(set_refresh < set_expire)
set = set_refresh;
else set = set_expire;
set_min = zone->soa_disk_acquired + XFRD_LOWERBOUND_REFRESH;
if(set < set_min)
set = set_min;
xfrd_set_timer(zone, set);
}
static void
xfrd_set_timer_retry(xfrd_zone_t* zone)
{
/* set timer for next retry or expire timeout if earlier. */
if(zone->soa_disk_acquired == 0) {
/* if no information, use reasonable timeout */
xfrd_set_timer(zone, xfrd_time() + zone->fresh_xfr_timeout
+ random()%zone->fresh_xfr_timeout);
/* exponential backoff - some master data in zones is paid-for
but non-working, and will not get fixed. */
zone->fresh_xfr_timeout *= 2;
if(zone->fresh_xfr_timeout > XFRD_TRANSFER_TIMEOUT_MAX)
zone->fresh_xfr_timeout = XFRD_TRANSFER_TIMEOUT_MAX;
} else if(zone->state == xfrd_zone_expired ||
xfrd_time() + ntohl(zone->soa_disk.retry) <
zone->soa_disk_acquired + ntohl(zone->soa_disk.expire))
{
if(ntohl(zone->soa_disk.retry) < XFRD_LOWERBOUND_RETRY)
xfrd_set_timer(zone, xfrd_time() + XFRD_LOWERBOUND_RETRY);
else
xfrd_set_timer(zone, xfrd_time() + ntohl(zone->soa_disk.retry));
} else {
if(ntohl(zone->soa_disk.expire) < XFRD_LOWERBOUND_RETRY)
xfrd_set_timer(zone, xfrd_time() + XFRD_LOWERBOUND_RETRY);
else
xfrd_set_timer(zone, zone->soa_disk_acquired +
ntohl(zone->soa_disk.expire));
}
}
static void
xfrd_handle_zone(netio_type* ATTR_UNUSED(netio),
netio_handler_type *handler, netio_event_types_type event_types)
{
xfrd_zone_t* zone = (xfrd_zone_t*)handler->user_data;
if(zone->tcp_conn != -1) {
/* busy in tcp transaction */
if(xfrd_tcp_is_reading(xfrd->tcp_set, zone->tcp_conn) && event_types & NETIO_EVENT_READ) {
DEBUG(DEBUG_XFRD,1, (LOG_INFO, "xfrd: zone %s event tcp read", zone->apex_str));
xfrd_set_timer(zone, xfrd_time() + xfrd->tcp_set->tcp_timeout);
xfrd_tcp_read(xfrd->tcp_set, zone);
return;
} else if(!xfrd_tcp_is_reading(xfrd->tcp_set, zone->tcp_conn) && event_types & NETIO_EVENT_WRITE) {
DEBUG(DEBUG_XFRD,1, (LOG_INFO, "xfrd: zone %s event tcp write", zone->apex_str));
xfrd_set_timer(zone, xfrd_time() + xfrd->tcp_set->tcp_timeout);
xfrd_tcp_write(xfrd->tcp_set, zone);
return;
} else if(event_types & NETIO_EVENT_TIMEOUT) {
/* tcp connection timed out. Stop it. */
DEBUG(DEBUG_XFRD,1, (LOG_INFO, "xfrd: zone %s event tcp timeout", zone->apex_str));
xfrd_tcp_release(xfrd->tcp_set, zone);
/* continue to retry; as if a timeout happened */
event_types = NETIO_EVENT_TIMEOUT;
}
}
if(event_types & NETIO_EVENT_READ) {
/* busy in udp transaction */
DEBUG(DEBUG_XFRD,1, (LOG_INFO, "xfrd: zone %s event udp read", zone->apex_str));
xfrd_set_refresh_now(zone);
xfrd_udp_read(zone);
return;
}
/* timeout */
DEBUG(DEBUG_XFRD,1, (LOG_INFO, "xfrd: zone %s timeout", zone->apex_str));
if(handler->fd != -1) {
assert(zone->tcp_conn == -1);
xfrd_udp_release(zone);
}
if(zone->tcp_waiting) {
DEBUG(DEBUG_XFRD,1, (LOG_ERR, "xfrd: zone %s skips retry, TCP connections full",
zone->apex_str));
xfrd_unset_timer(zone);
return;
}
if(zone->udp_waiting) {
DEBUG(DEBUG_XFRD,1, (LOG_ERR, "xfrd: zone %s skips retry, UDP connections full",
zone->apex_str));
xfrd_unset_timer(zone);
return;
}
if(zone->soa_disk_acquired)
{
if (zone->state != xfrd_zone_expired &&
(uint32_t)xfrd_time() >= zone->soa_disk_acquired + ntohl(zone->soa_disk.expire)) {
/* zone expired */
log_msg(LOG_ERR, "xfrd: zone %s has expired", zone->apex_str);
xfrd_set_zone_state(zone, xfrd_zone_expired);
}
else if(zone->state == xfrd_zone_ok &&
(uint32_t)xfrd_time() >= zone->soa_disk_acquired + ntohl(zone->soa_disk.refresh)) {
/* zone goes to refreshing state. */
DEBUG(DEBUG_XFRD,1, (LOG_INFO, "xfrd: zone %s is refreshing", zone->apex_str));
xfrd_set_zone_state(zone, xfrd_zone_refreshing);
}
}
/* make a new request */
xfrd_make_request(zone);
}
void
xfrd_make_request(xfrd_zone_t* zone)
{
if(zone->next_master != -1) {
/* we are told to use this next master */
DEBUG(DEBUG_XFRD,1, (LOG_INFO,
"xfrd zone %s use master %i",
zone->apex_str, zone->next_master));
zone->master_num = zone->next_master;
zone->master = acl_find_num(
zone->zone_options->request_xfr, zone->master_num);
/* if there is no next master, fallback to use the first one */
if(!zone->master) {
zone->master = zone->zone_options->request_xfr;
zone->master_num = 0;
}
/* fallback to cycle master */
zone->next_master = -1;
zone->round_num = 0; /* fresh set of retries after notify */
} else {
/* cycle master */
if(zone->round_num != -1 && zone->master && zone->master->next)
{
/* try the next master */
zone->master = zone->master->next;
zone->master_num++;
} else {
/* start a new round */
zone->master = zone->zone_options->request_xfr;
zone->master_num = 0;
zone->round_num++;
}
if(zone->round_num >= XFRD_MAX_ROUNDS) {
/* tried all servers that many times, wait */
zone->round_num = -1;
xfrd_set_timer_retry(zone);
DEBUG(DEBUG_XFRD,1, (LOG_INFO,
"xfrd zone %s makereq wait_retry, rd %d mr %d nx %d",
zone->apex_str, zone->round_num, zone->master_num, zone->next_master));
return;
}
}
/* cache ixfr_disabled only for XFRD_NO_IXFR_CACHE time */
if (zone->master->ixfr_disabled &&
(zone->master->ixfr_disabled + XFRD_NO_IXFR_CACHE) <= time(NULL)) {
DEBUG(DEBUG_XFRD,1, (LOG_INFO, "clear negative caching ixfr "
"disabled for master %s num "
"%d ",
zone->master->ip_address_spec, zone->master_num));
zone->master->ixfr_disabled = 0;
}
DEBUG(DEBUG_XFRD,1, (LOG_INFO, "xfrd zone %s make request round %d mr %d nx %d",
zone->apex_str, zone->round_num, zone->master_num, zone->next_master));
/* perform xfr request */
if (!zone->master->use_axfr_only && zone->soa_disk_acquired > 0 &&
!zone->master->ixfr_disabled) {
if (zone->master->allow_udp) {
xfrd_set_timer(zone, xfrd_time() + XFRD_UDP_TIMEOUT);
xfrd_udp_obtain(zone);
}
else { /* doing 3 rounds of IXFR/TCP might not be useful */
xfrd_set_timer(zone, xfrd_time() + xfrd->tcp_set->tcp_timeout);
xfrd_tcp_obtain(xfrd->tcp_set, zone);
}
}
else if (zone->master->use_axfr_only || zone->soa_disk_acquired <= 0) {
xfrd_set_timer(zone, xfrd_time() + xfrd->tcp_set->tcp_timeout);
xfrd_tcp_obtain(xfrd->tcp_set, zone);
}
else if (zone->master->ixfr_disabled) {
if (zone->zone_options->allow_axfr_fallback) {
xfrd_set_timer(zone, xfrd_time() + xfrd->tcp_set->tcp_timeout);
xfrd_tcp_obtain(xfrd->tcp_set, zone);
}
else
DEBUG(DEBUG_XFRD,1, (LOG_INFO, "xfrd zone %s axfr "
"fallback not allowed, skipping master %s.",
zone->apex_str, zone->master->ip_address_spec));
}
}
static void
xfrd_udp_obtain(xfrd_zone_t* zone)
{
assert(zone->udp_waiting == 0);
if(zone->tcp_conn != -1) {
/* no tcp and udp at the same time */
xfrd_tcp_release(xfrd->tcp_set, zone);
}
if(xfrd->udp_use_num < XFRD_MAX_UDP) {
xfrd->udp_use_num++;
zone->zone_handler.fd = xfrd_send_ixfr_request_udp(zone);
if(zone->zone_handler.fd == -1)
xfrd->udp_use_num--;
return;
}
/* queue the zone as last */
zone->udp_waiting = 1;
zone->udp_waiting_next = NULL;
if(!xfrd->udp_waiting_first)
xfrd->udp_waiting_first = zone;
if(xfrd->udp_waiting_last)
xfrd->udp_waiting_last->udp_waiting_next = zone;
xfrd->udp_waiting_last = zone;
xfrd_unset_timer(zone);
}
time_t
xfrd_time()
{
if(!xfrd->got_time) {
xfrd->current_time = time(0);
xfrd->got_time = 1;
}
return xfrd->current_time;
}
void
xfrd_copy_soa(xfrd_soa_t* soa, rr_type* rr)
{
const uint8_t* rr_ns_wire = dname_name(domain_dname(rdata_atom_domain(rr->rdatas[0])));
uint8_t rr_ns_len = domain_dname(rdata_atom_domain(rr->rdatas[0]))->name_size;
const uint8_t* rr_em_wire = dname_name(domain_dname(rdata_atom_domain(rr->rdatas[1])));
uint8_t rr_em_len = domain_dname(rdata_atom_domain(rr->rdatas[1]))->name_size;
if(rr->type != TYPE_SOA || rr->rdata_count != 7) {
log_msg(LOG_ERR, "xfrd: copy_soa called with bad rr, type %d rrs %u.",
rr->type, rr->rdata_count);
return;
}
DEBUG(DEBUG_XFRD,1, (LOG_INFO, "xfrd: copy_soa rr, type %d rrs %u, ttl %u.",
rr->type, rr->rdata_count, rr->ttl));
soa->type = htons(rr->type);
soa->klass = htons(rr->klass);
soa->ttl = htonl(rr->ttl);
soa->rdata_count = htons(rr->rdata_count);
/* copy dnames */
soa->prim_ns[0] = rr_ns_len;
memcpy(soa->prim_ns+1, rr_ns_wire, rr_ns_len);
soa->email[0] = rr_em_len;
memcpy(soa->email+1, rr_em_wire, rr_em_len);
/* already in network format */
memcpy(&soa->serial, rdata_atom_data(rr->rdatas[2]), sizeof(uint32_t));
memcpy(&soa->refresh, rdata_atom_data(rr->rdatas[3]), sizeof(uint32_t));
memcpy(&soa->retry, rdata_atom_data(rr->rdatas[4]), sizeof(uint32_t));
memcpy(&soa->expire, rdata_atom_data(rr->rdatas[5]), sizeof(uint32_t));
memcpy(&soa->minimum, rdata_atom_data(rr->rdatas[6]), sizeof(uint32_t));
DEBUG(DEBUG_XFRD,1, (LOG_INFO,
"xfrd: copy_soa rr, serial %u refresh %u retry %u expire %u",
ntohl(soa->serial), ntohl(soa->refresh), ntohl(soa->retry),
ntohl(soa->expire)));
}
static void
xfrd_set_zone_state(xfrd_zone_t* zone, enum xfrd_zone_state s)
{
if(s != zone->state) {
enum xfrd_zone_state old = zone->state;
zone->state = s;
if(s == xfrd_zone_expired || old == xfrd_zone_expired) {
xfrd_send_expire_notification(zone);
}
}
}
void
xfrd_set_refresh_now(xfrd_zone_t* zone)
{
xfrd_set_timer(zone, xfrd_time());
DEBUG(DEBUG_XFRD,1, (LOG_INFO, "xfrd zone %s sets timeout right now, state %d",
zone->apex_str, zone->state));
}
void
xfrd_unset_timer(xfrd_zone_t* zone)
{
zone->zone_handler.timeout = NULL;
}
void
xfrd_set_timer(xfrd_zone_t* zone, time_t t)
{
/* randomize the time, within 90%-100% of original */
/* not later so zones cannot expire too late */
/* only for times far in the future */
if(t > xfrd_time() + 10) {
time_t extra = t - xfrd_time();
time_t base = extra*9/10;
t = xfrd_time() + base + random()%(extra-base);
}
zone->zone_handler.timeout = &zone->timeout;
zone->timeout.tv_sec = t;
zone->timeout.tv_nsec = 0;
}
void
xfrd_handle_incoming_soa(xfrd_zone_t* zone,
xfrd_soa_t* soa, time_t acquired)
{
if(soa == NULL) {
/* nsd no longer has a zone in memory */
zone->soa_nsd_acquired = 0;
xfrd_set_zone_state(zone, xfrd_zone_refreshing);
xfrd_set_refresh_now(zone);
return;
}
if(zone->soa_nsd_acquired && soa->serial == zone->soa_nsd.serial)
return;
if(zone->soa_disk_acquired && soa->serial == zone->soa_disk.serial)
{
/* soa in disk has been loaded in memory */
log_msg(LOG_INFO, "Zone %s serial %u is updated to %u.",
zone->apex_str, ntohl(zone->soa_nsd.serial),
ntohl(soa->serial));
zone->soa_nsd = zone->soa_disk;
zone->soa_nsd_acquired = zone->soa_disk_acquired;
if((uint32_t)xfrd_time() - zone->soa_disk_acquired
< ntohl(zone->soa_disk.refresh))
{
/* zone ok, wait for refresh time */
xfrd_set_zone_state(zone, xfrd_zone_ok);
zone->round_num = -1;
xfrd_set_timer_refresh(zone);
} else if((uint32_t)xfrd_time() - zone->soa_disk_acquired
< ntohl(zone->soa_disk.expire))
{
/* zone refreshing */
xfrd_set_zone_state(zone, xfrd_zone_refreshing);
xfrd_set_refresh_now(zone);
}
if((uint32_t)xfrd_time() - zone->soa_disk_acquired
>= ntohl(zone->soa_disk.expire)) {
/* zone expired */
xfrd_set_zone_state(zone, xfrd_zone_expired);
xfrd_set_refresh_now(zone);
}
if(zone->soa_notified_acquired != 0 &&
(zone->soa_notified.serial == 0 ||
compare_serial(ntohl(zone->soa_disk.serial),
ntohl(zone->soa_notified.serial)) >= 0))
{ /* read was in response to this notification */
zone->soa_notified_acquired = 0;
}
if(zone->soa_notified_acquired && zone->state == xfrd_zone_ok)
{
/* refresh because of notification */
xfrd_set_zone_state(zone, xfrd_zone_refreshing);
xfrd_set_refresh_now(zone);
}
xfrd_send_notify(xfrd->notify_zones, zone->apex, &zone->soa_nsd);
return;
}
/* user must have manually provided zone data */
DEBUG(DEBUG_XFRD,1, (LOG_INFO,
"xfrd: zone %s serial %u from unknown source. refreshing",
zone->apex_str, ntohl(soa->serial)));
zone->soa_nsd = *soa;
zone->soa_disk = *soa;
zone->soa_nsd_acquired = acquired;
zone->soa_disk_acquired = acquired;
if(zone->soa_notified_acquired != 0 &&
(zone->soa_notified.serial == 0 ||
compare_serial(ntohl(zone->soa_disk.serial),
ntohl(zone->soa_notified.serial)) >= 0))
{ /* user provided in response to this notification */
zone->soa_notified_acquired = 0;
}
xfrd_set_zone_state(zone, xfrd_zone_refreshing);
xfrd_set_refresh_now(zone);
xfrd_send_notify(xfrd->notify_zones, zone->apex, &zone->soa_nsd);
}
static void
xfrd_send_expire_notification(xfrd_zone_t* zone)
{
if(zone->dirty)
return; /* already queued */
/* enqueue */
assert(xfrd->dirty_zones->num < xfrd->dirty_zones->capacity);
zone->dirty = 1;
stack_push(xfrd->dirty_zones, (void*)zone);
xfrd->ipc_handler.event_types |= NETIO_EVENT_WRITE;
}
int
xfrd_udp_read_packet(buffer_type* packet, int fd)
{
ssize_t received;
/* read the data */
buffer_clear(packet);
received = recvfrom(fd, buffer_begin(packet), buffer_remaining(packet),
0, NULL, NULL);
if(received == -1) {
log_msg(LOG_ERR, "xfrd: recvfrom failed: %s",
strerror(errno));
return 0;
}
buffer_set_limit(packet, received);
return 1;
}
void
xfrd_udp_release(xfrd_zone_t* zone)
{
assert(zone->udp_waiting == 0);
if(zone->zone_handler.fd != -1)
close(zone->zone_handler.fd);
zone->zone_handler.fd = -1;
/* see if there are waiting zones */
if(xfrd->udp_use_num == XFRD_MAX_UDP)
{
while(xfrd->udp_waiting_first) {
/* snip off waiting list */
xfrd_zone_t* wz = xfrd->udp_waiting_first;
assert(wz->udp_waiting);
wz->udp_waiting = 0;
xfrd->udp_waiting_first = wz->udp_waiting_next;
if(xfrd->udp_waiting_last == wz)
xfrd->udp_waiting_last = NULL;
/* see if this zone needs udp connection */
if(wz->tcp_conn == -1) {
wz->zone_handler.fd =
xfrd_send_ixfr_request_udp(wz);
if(wz->zone_handler.fd != -1)
return;
}
}
}
/* no waiting zones */
if(xfrd->udp_use_num > 0)
xfrd->udp_use_num--;
}
static void
xfrd_udp_read(xfrd_zone_t* zone)
{
DEBUG(DEBUG_XFRD,1, (LOG_INFO, "xfrd: zone %s read udp data", zone->apex_str));
if(!xfrd_udp_read_packet(xfrd->packet, zone->zone_handler.fd)) {
xfrd_udp_release(zone);
return;
}
switch(xfrd_handle_received_xfr_packet(zone, xfrd->packet)) {
case xfrd_packet_tcp:
xfrd_set_timer(zone, xfrd_time() + xfrd->tcp_set->tcp_timeout);
xfrd_udp_release(zone);
xfrd_tcp_obtain(xfrd->tcp_set, zone);
break;
case xfrd_packet_transfer:
case xfrd_packet_newlease:
/* nothing more to do */
assert(zone->round_num == -1);
xfrd_udp_release(zone);
break;
case xfrd_packet_notimpl:
zone->master->ixfr_disabled = time(NULL);
/* drop packet */
xfrd_udp_release(zone);
/* query next server */
xfrd_make_request(zone);
break;
case xfrd_packet_more:
case xfrd_packet_bad:
default:
/* drop packet */
xfrd_udp_release(zone);
/* query next server */
xfrd_make_request(zone);
break;
}
}
int
xfrd_send_udp(acl_options_t* acl, buffer_type* packet, acl_options_t* ifc)
{
#ifdef INET6
struct sockaddr_storage to;
#else
struct sockaddr_in to;
#endif /* INET6 */
int fd, family;
/* this will set the remote port to acl->port or TCP_PORT */
socklen_t to_len = xfrd_acl_sockaddr_to(acl, &to);
/* get the address family of the remote host */
if(acl->is_ipv6) {
#ifdef INET6
family = PF_INET6;
#else
return -1;
#endif /* INET6 */
} else {
family = PF_INET;
}
fd = socket(family, SOCK_DGRAM, IPPROTO_UDP);
if(fd == -1) {
log_msg(LOG_ERR, "xfrd: cannot create udp socket to %s: %s",
acl->ip_address_spec, strerror(errno));
return -1;
}
/* bind it */
if (!xfrd_bind_local_interface(fd, ifc, acl, 0)) {
log_msg(LOG_ERR, "xfrd: cannot bind outgoing interface '%s' to "
"udp socket: No matching ip addresses found",
ifc->ip_address_spec);
return -1;
}
/* send it (udp) */
if(sendto(fd,
buffer_current(packet),
buffer_remaining(packet), 0,
(struct sockaddr*)&to, to_len) == -1)
{
log_msg(LOG_ERR, "xfrd: sendto %s failed %s",
acl->ip_address_spec, strerror(errno));
return -1;
}
return fd;
}
int
xfrd_bind_local_interface(int sockd, acl_options_t* ifc, acl_options_t* acl,
int tcp)
{
#ifdef SO_LINGER
struct linger linger = {1, 0};
#endif
socklen_t frm_len;
#ifdef INET6
struct sockaddr_storage frm;
#else
struct sockaddr_in frm;
#endif /* INET6 */
if (!ifc) /* no outgoing interface set */
return 1;
while (ifc) {
if (ifc->is_ipv6 != acl->is_ipv6) {
/* check if we have a matching address family */
ifc = ifc->next;
continue;
}
DEBUG(DEBUG_XFRD,1, (LOG_INFO, "xfrd: bind() %s to %s socket",
ifc->ip_address_spec, tcp? "tcp":"udp"));
frm_len = xfrd_acl_sockaddr_frm(ifc, &frm);
if (tcp) {
#ifdef SO_REUSEADDR
if (setsockopt(sockd, SOL_SOCKET, SO_REUSEADDR, &frm,
frm_len) < 0) {
VERBOSITY(2, (LOG_WARNING, "xfrd: setsockopt "
"SO_REUSEADDR failed: %s", strerror(errno)));
}
#else
VERBOSITY(2, (LOG_WARNING, "xfrd: setsockopt SO_REUSEADDR "
"failed: SO_REUSEADDR not defined"));
#endif /* SO_REUSEADDR */
if (ifc->port != 0) {
#ifdef SO_LINGER
if (setsockopt(sockd, SOL_SOCKET, SO_LINGER,
&linger, sizeof(linger)) < 0) {
VERBOSITY(2, (LOG_WARNING, "xfrd: setsockopt "
"SO_LINGER failed: %s", strerror(errno)));
}
#else
VERBOSITY(2, (LOG_WARNING, "xfrd: setsockopt SO_LINGER "
"failed: SO_LINGER not defined"));
#endif /* SO_LINGER */
}
}
/* found one */
if(bind(sockd, (struct sockaddr*)&frm, frm_len) >= 0) {
DEBUG(DEBUG_XFRD,2, (LOG_INFO, "xfrd: bind() %s to %s "
"socket was successful",
ifc->ip_address_spec, tcp? "tcp":"udp"));
return 1;
}
DEBUG(DEBUG_XFRD,2, (LOG_INFO, "xfrd: bind() %s to %s socket"
"failed: %s",
ifc->ip_address_spec, tcp? "tcp":"udp",
strerror(errno)));
/* try another */
ifc = ifc->next;
}
log_msg(LOG_WARNING, "xfrd: could not bind source address:port to "
"socket: %s", strerror(errno));
return 0;
}
void
xfrd_tsig_sign_request(buffer_type* packet, tsig_record_type* tsig,
acl_options_t* acl)
{
tsig_algorithm_type* algo;
assert(acl->key_options && acl->key_options->tsig_key);
algo = tsig_get_algorithm_by_name(acl->key_options->algorithm);
if(!algo) {
log_msg(LOG_ERR, "tsig unknown algorithm %s",
acl->key_options->algorithm);
return;
}
assert(algo);
tsig_init_record(tsig, algo, acl->key_options->tsig_key);
tsig_init_query(tsig, ID(packet));
tsig_prepare(tsig);
tsig_update(tsig, packet, buffer_position(packet));
tsig_sign(tsig);
tsig_append_rr(tsig, packet);
ARCOUNT_SET(packet, ARCOUNT(packet) + 1);
DEBUG(DEBUG_XFRD,1, (LOG_INFO, "appending tsig to packet"));
/* prepare for validating tsigs */
tsig_prepare(tsig);
}
static int
xfrd_send_ixfr_request_udp(xfrd_zone_t* zone)
{
int fd;
/* make sure we have a master to query the ixfr request to */
assert(zone->master);
if(zone->tcp_conn != -1) {
/* tcp is using the zone_handler.fd */
log_msg(LOG_ERR, "xfrd: %s tried to send udp whilst tcp engaged",
zone->apex_str);
return -1;
}
xfrd_setup_packet(xfrd->packet, TYPE_IXFR, CLASS_IN, zone->apex);
zone->query_id = ID(xfrd->packet);
zone->msg_seq_nr = 0;
zone->msg_rr_count = 0;
DEBUG(DEBUG_XFRD,1, (LOG_INFO, "sent query with ID %d", zone->query_id));
NSCOUNT_SET(xfrd->packet, 1);
xfrd_write_soa_buffer(xfrd->packet, zone->apex, &zone->soa_disk);
/* if we have tsig keys, sign the ixfr query */
if(zone->master->key_options && zone->master->key_options->tsig_key) {
xfrd_tsig_sign_request(xfrd->packet, &zone->tsig, zone->master);
}
buffer_flip(xfrd->packet);
xfrd_set_timer(zone, xfrd_time() + XFRD_UDP_TIMEOUT);
if((fd = xfrd_send_udp(zone->master, xfrd->packet,
zone->zone_options->outgoing_interface)) == -1)
return -1;
DEBUG(DEBUG_XFRD,1, (LOG_INFO,
"xfrd sent udp request for ixfr=%u for zone %s to %s",
ntohl(zone->soa_disk.serial),
zone->apex_str, zone->master->ip_address_spec));
return fd;
}
static int xfrd_parse_soa_info(buffer_type* packet, xfrd_soa_t* soa)
{
if(!buffer_available(packet, 10))
return 0;
soa->type = htons(buffer_read_u16(packet));
soa->klass = htons(buffer_read_u16(packet));
soa->ttl = htonl(buffer_read_u32(packet));
if(ntohs(soa->type) != TYPE_SOA || ntohs(soa->klass) != CLASS_IN)
{
return 0;
}
if(!buffer_available(packet, buffer_read_u16(packet)) /* rdata length */ ||
!(soa->prim_ns[0] = dname_make_wire_from_packet(soa->prim_ns+1, packet, 1)) ||
!(soa->email[0] = dname_make_wire_from_packet(soa->email+1, packet, 1)))
{
return 0;
}
soa->serial = htonl(buffer_read_u32(packet));
soa->refresh = htonl(buffer_read_u32(packet));
soa->retry = htonl(buffer_read_u32(packet));
soa->expire = htonl(buffer_read_u32(packet));
soa->minimum = htonl(buffer_read_u32(packet));
return 1;
}
/*
* Check the RRs in an IXFR/AXFR reply.
* returns 0 on error, 1 on correct parseable packet.
* done = 1 if the last SOA in an IXFR/AXFR has been seen.
* soa then contains that soa info.
* (soa contents is modified by the routine)
*/
static int
xfrd_xfr_check_rrs(xfrd_zone_t* zone, buffer_type* packet, size_t count,
int *done, xfrd_soa_t* soa)
{
/* first RR has already been checked */
uint16_t type, klass, rrlen;
uint32_t ttl;
size_t i, soapos;
for(i=0; i<count; ++i,++zone->msg_rr_count)
{
if(!packet_skip_dname(packet))
return 0;
if(!buffer_available(packet, 10))
return 0;
soapos = buffer_position(packet);
type = buffer_read_u16(packet);
klass = buffer_read_u16(packet);
ttl = buffer_read_u32(packet);
rrlen = buffer_read_u16(packet);
if(!buffer_available(packet, rrlen))
return 0;
if(type == TYPE_SOA) {
/* check the SOAs */
size_t mempos = buffer_position(packet);
buffer_set_position(packet, soapos);
if(!xfrd_parse_soa_info(packet, soa))
return 0;
if(zone->msg_rr_count == 1 &&
ntohl(soa->serial) != zone->msg_new_serial) {
/* 2nd RR is SOA with lower serial, this is an IXFR */
zone->msg_is_ixfr = 1;
if(!zone->soa_disk_acquired)
return 0; /* got IXFR but need AXFR */
if(ntohl(soa->serial) != ntohl(zone->soa_disk.serial))
return 0; /* bad start serial in IXFR */
zone->msg_old_serial = ntohl(soa->serial);
}
else if(ntohl(soa->serial) == zone->msg_new_serial) {
/* saw another SOA of new serial. */
if(zone->msg_is_ixfr == 1) {
zone->msg_is_ixfr = 2; /* seen middle SOA in ixfr */
} else {
/* 2nd SOA for AXFR or 3rd newSOA for IXFR */
*done = 1;
}
}
buffer_set_position(packet, mempos);
}
buffer_skip(packet, rrlen);
}
/* packet seems to have a valid DNS RR structure */
return 1;
}
static int
xfrd_xfr_process_tsig(xfrd_zone_t* zone, buffer_type* packet)
{
int have_tsig = 0;
assert(zone && zone->master && zone->master->key_options
&& zone->master->key_options->tsig_key && packet);
if(!tsig_find_rr(&zone->tsig, packet)) {
log_msg(LOG_ERR, "xfrd: zone %s, from %s: malformed tsig RR",
zone->apex_str, zone->master->ip_address_spec);
return 0;
}
if(zone->tsig.status == TSIG_OK) {
have_tsig = 1;
}
if(have_tsig) {
/* strip the TSIG resource record off... */
buffer_set_limit(packet, zone->tsig.position);
ARCOUNT_SET(packet, ARCOUNT(packet) - 1);
}
/* keep running the TSIG hash */
tsig_update(&zone->tsig, packet, buffer_limit(packet));
if(have_tsig) {
if (!tsig_verify(&zone->tsig)) {
log_msg(LOG_ERR, "xfrd: zone %s, from %s: bad tsig signature",
zone->apex_str, zone->master->ip_address_spec);
return 0;
}
DEBUG(DEBUG_XFRD,1, (LOG_INFO, "xfrd: zone %s, from %s: good tsig signature",
zone->apex_str, zone->master->ip_address_spec));
/* prepare for next tsigs */
tsig_prepare(&zone->tsig);
}
else if(zone->tsig.updates_since_last_prepare > XFRD_TSIG_MAX_UNSIGNED) {
/* we allow a number of non-tsig signed packets */
log_msg(LOG_INFO, "xfrd: zone %s, from %s: too many consecutive "
"packets without TSIG", zone->apex_str,
zone->master->ip_address_spec);
return 0;
}
if(!have_tsig && zone->msg_seq_nr == 0) {
log_msg(LOG_ERR, "xfrd: zone %s, from %s: no tsig in first packet of reply",
zone->apex_str, zone->master->ip_address_spec);
return 0;
}
return 1;
}
/* parse the received packet. returns xfrd packet result code. */
static enum xfrd_packet_result
xfrd_parse_received_xfr_packet(xfrd_zone_t* zone, buffer_type* packet,
xfrd_soa_t* soa)
{
size_t rr_count;
size_t qdcount = QDCOUNT(packet);
size_t ancount = ANCOUNT(packet), ancount_todo;
int done = 0;
/* has to be axfr / ixfr reply */
if(!buffer_available(packet, QHEADERSZ)) {
log_msg(LOG_INFO, "packet too small");
return xfrd_packet_bad;
}
/* only check ID in first response message. Could also check that
* AA bit and QR bit are set, but not needed.
*/
DEBUG(DEBUG_XFRD,2, (LOG_INFO,
"got query with ID %d and %d needed", ID(packet), zone->query_id));
if(ID(packet) != zone->query_id) {
log_msg(LOG_ERR, "xfrd: zone %s received bad query id from %s, "
"dropped",
zone->apex_str, zone->master->ip_address_spec);
return xfrd_packet_bad;
}
/* check RCODE in all response messages */
if(RCODE(packet) != RCODE_OK) {
log_msg(LOG_ERR, "xfrd: zone %s received error code %s from "
"%s",
zone->apex_str, rcode2str(RCODE(packet)),
zone->master->ip_address_spec);
if (RCODE(packet) == RCODE_IMPL ||
RCODE(packet) == RCODE_FORMAT) {
return xfrd_packet_notimpl;
}
return xfrd_packet_bad;
}
/* check TSIG */
if(zone->master->key_options) {
if(!xfrd_xfr_process_tsig(zone, packet)) {
DEBUG(DEBUG_XFRD,1, (LOG_ERR, "dropping xfr reply due "
"to bad TSIG"));
return xfrd_packet_bad;
}
}
buffer_skip(packet, QHEADERSZ);
/* skip question section */
for(rr_count = 0; rr_count < qdcount; ++rr_count) {
if (!packet_skip_rr(packet, 1)) {
log_msg(LOG_ERR, "xfrd: zone %s, from %s: bad RR in "
"question section",
zone->apex_str, zone->master->ip_address_spec);
return xfrd_packet_bad;
}
}
if(zone->msg_rr_count == 0 && ancount == 0) {
if(zone->tcp_conn == -1 && TC(packet)) {
DEBUG(DEBUG_XFRD,1, (LOG_INFO, "xfrd: TC flagged"));
return xfrd_packet_tcp;
}
DEBUG(DEBUG_XFRD,1, (LOG_INFO, "xfrd: too short xfr packet: no "
"answer"));
return xfrd_packet_bad;
}
ancount_todo = ancount;
if(zone->msg_rr_count == 0) {
/* parse the first RR, see if it is a SOA */
if(!packet_skip_dname(packet) ||
!xfrd_parse_soa_info(packet, soa))
{
DEBUG(DEBUG_XFRD,1, (LOG_ERR, "xfrd: zone %s, from %s: "
"no SOA begins answer"
" section",
zone->apex_str, zone->master->ip_address_spec));
return xfrd_packet_bad;
}
if(zone->soa_disk_acquired != 0 &&
zone->state != xfrd_zone_expired /* if expired - accept anything */ &&
compare_serial(ntohl(soa->serial), ntohl(zone->soa_disk.serial)) < 0) {
DEBUG(DEBUG_XFRD,1, (LOG_INFO,
"xfrd: zone %s ignoring old serial from %s",
zone->apex_str, zone->master->ip_address_spec));
VERBOSITY(1, (LOG_INFO,
"xfrd: zone %s ignoring old serial from %s",
zone->apex_str, zone->master->ip_address_spec));
return xfrd_packet_bad;
}
if(zone->soa_disk_acquired != 0 && zone->soa_disk.serial == soa->serial) {
DEBUG(DEBUG_XFRD,1, (LOG_INFO, "xfrd: zone %s got "
"update indicating "
"current serial",
zone->apex_str));
/* (even if notified) the lease on the current soa is renewed */
zone->soa_disk_acquired = xfrd_time();
if(zone->soa_nsd.serial == soa->serial)
zone->soa_nsd_acquired = xfrd_time();
xfrd_set_zone_state(zone, xfrd_zone_ok);
DEBUG(DEBUG_XFRD,1, (LOG_INFO, "xfrd: zone %s is ok",
zone->apex_str));
if(zone->soa_notified_acquired == 0) {
/* not notified or anything, so stop asking around */
zone->round_num = -1; /* next try start a new round */
xfrd_set_timer_refresh(zone);
return xfrd_packet_newlease;
}
/* try next master */
return xfrd_packet_bad;
}
DEBUG(DEBUG_XFRD,1, (LOG_INFO, "IXFR reply has ok serial (have \
%u, reply %u).", ntohl(zone->soa_disk.serial), ntohl(soa->serial)));
/* serial is newer than soa_disk */
if(ancount == 1) {
/* single record means it is like a notify */
(void)xfrd_handle_incoming_notify(zone, soa);
}
else if(zone->soa_notified_acquired && zone->soa_notified.serial &&
compare_serial(ntohl(zone->soa_notified.serial), ntohl(soa->serial)) < 0) {
/* this AXFR/IXFR notifies me that an even newer serial exists */
zone->soa_notified.serial = soa->serial;
}
zone->msg_new_serial = ntohl(soa->serial);
zone->msg_rr_count = 1;
zone->msg_is_ixfr = 0;
if(zone->soa_disk_acquired)
zone->msg_old_serial = ntohl(zone->soa_disk.serial);
else zone->msg_old_serial = 0;
ancount_todo = ancount - 1;
}
if(zone->tcp_conn == -1 && TC(packet)) {
DEBUG(DEBUG_XFRD,1, (LOG_INFO,
"xfrd: zone %s received TC from %s. retry tcp.",
zone->apex_str, zone->master->ip_address_spec));
return xfrd_packet_tcp;
}
if(zone->tcp_conn == -1 && ancount < 2) {
/* too short to be a real ixfr/axfr data transfer: need at */
/* least two RRs in the answer section. */
/* The serial is newer, so try tcp to this master. */
DEBUG(DEBUG_XFRD,1, (LOG_INFO, "xfrd: udp reply is short. Try "
"tcp anyway."));
return xfrd_packet_tcp;
}
if(!xfrd_xfr_check_rrs(zone, packet, ancount_todo, &done, soa))
{
DEBUG(DEBUG_XFRD,1, (LOG_INFO, "xfrd: zone %s sent bad xfr "
"reply.", zone->apex_str));
return xfrd_packet_bad;
}
if(zone->tcp_conn == -1 && done == 0) {
DEBUG(DEBUG_XFRD,1, (LOG_INFO, "xfrd: udp reply incomplete"));
return xfrd_packet_bad;
}
if(done == 0)
return xfrd_packet_more;
if(zone->master->key_options) {
if(zone->tsig.updates_since_last_prepare != 0) {
log_msg(LOG_INFO, "xfrd: last packet of reply has no "
"TSIG");
return xfrd_packet_bad;
}
}
return xfrd_packet_transfer;
}
enum xfrd_packet_result
xfrd_handle_received_xfr_packet(xfrd_zone_t* zone, buffer_type* packet)
{
xfrd_soa_t soa;
enum xfrd_packet_result res;
/* parse and check the packet - see if it ends the xfr */
switch((res=xfrd_parse_received_xfr_packet(zone, packet, &soa)))
{
case xfrd_packet_more:
case xfrd_packet_transfer:
/* continue with commit */
break;
case xfrd_packet_newlease:
return xfrd_packet_newlease;
case xfrd_packet_tcp:
return xfrd_packet_tcp;
case xfrd_packet_notimpl:
case xfrd_packet_bad:
default:
{
/* rollback */
if(zone->msg_seq_nr > 0) {
/* do not process xfr - if only one part simply ignore it. */
/* rollback previous parts of commit */
buffer_clear(packet);
buffer_printf(packet, "xfrd: zone %s xfr "
"rollback serial %u at "
"time %u from %s of %u "
"parts",
zone->apex_str,
(int)zone->msg_new_serial,
(int)xfrd_time(),
zone->master->ip_address_spec,
zone->msg_seq_nr);
buffer_flip(packet);
diff_write_commit(zone->apex_str,
zone->msg_old_serial,
zone->msg_new_serial,
zone->query_id, zone->msg_seq_nr, 0,
(char*)buffer_begin(packet),
xfrd->nsd->options);
DEBUG(DEBUG_XFRD,1, (LOG_INFO, "xfrd: zone %s "
"xfr reverted "
"\"%s\"",
zone->apex_str,
(char*)buffer_begin(packet)));
}
if (res == xfrd_packet_notimpl)
return res;
else
return xfrd_packet_bad;
}
}
/* dump reply on disk to diff file */
diff_write_packet(zone->apex_str, zone->msg_new_serial, zone->query_id,
zone->msg_seq_nr, buffer_begin(packet), buffer_limit(packet),
xfrd->nsd->options);
VERBOSITY(1, (LOG_INFO,
"xfrd: zone %s written received XFR from %s with serial %u to "
"disk", zone->apex_str, zone->master->ip_address_spec,
(int)zone->msg_new_serial));
zone->msg_seq_nr++;
if(res == xfrd_packet_more) {
/* wait for more */
return xfrd_packet_more;
}
/* done. we are completely sure of this */
buffer_clear(packet);
buffer_printf(packet, "xfrd: zone %s received update to serial %u at "
"time %u from %s in %u parts",
zone->apex_str, (int)zone->msg_new_serial, (int)xfrd_time(),
zone->master->ip_address_spec, zone->msg_seq_nr);
if(zone->master->key_options) {
buffer_printf(packet, " TSIG verified with key %s",
zone->master->key_options->name);
}
buffer_flip(packet);
diff_write_commit(zone->apex_str, zone->msg_old_serial,
zone->msg_new_serial, zone->query_id, zone->msg_seq_nr, 1,
(char*)buffer_begin(packet), xfrd->nsd->options);
VERBOSITY(1, (LOG_INFO, "xfrd: zone %s committed \"%s\"",
zone->apex_str, (char*)buffer_begin(packet)));
/* update the disk serial no. */
zone->soa_disk_acquired = xfrd_time();
zone->soa_disk = soa;
if(zone->soa_notified_acquired && (
zone->soa_notified.serial == 0 ||
compare_serial(htonl(zone->soa_disk.serial),
htonl(zone->soa_notified.serial)) >= 0))
{
zone->soa_notified_acquired = 0;
}
if(!zone->soa_notified_acquired) {
/* do not set expired zone to ok:
* it would cause nsd to start answering
* bad data, since the zone is not loaded yet.
* if nsd does not reload < retry time, more
* queries (for even newer versions) are made.
* For expired zone after reload it is set ok (SOAINFO ipc). */
if(zone->state != xfrd_zone_expired)
xfrd_set_zone_state(zone, xfrd_zone_ok);
DEBUG(DEBUG_XFRD,1, (LOG_INFO,
"xfrd: zone %s is waiting for reload",
zone->apex_str));
zone->round_num = -1; /* next try start anew */
xfrd_set_timer_refresh(zone);
xfrd_set_reload_timeout();
return xfrd_packet_transfer;
} else {
/* try to get an even newer serial */
/* pretend it was bad to continue queries */
xfrd_set_reload_timeout();
return xfrd_packet_bad;
}
}
static void
xfrd_set_reload_timeout()
{
if(xfrd->nsd->options->xfrd_reload_timeout == -1)
return; /* automatic reload disabled. */
if(xfrd->reload_timeout.tv_sec == 0 ||
xfrd_time() >= xfrd->reload_timeout.tv_sec ) {
/* no reload wait period (or it passed), do it right away */
xfrd->need_to_send_reload = 1;
xfrd->ipc_handler.event_types |= NETIO_EVENT_WRITE;
/* start reload wait period */
xfrd->reload_timeout.tv_sec = xfrd_time() +
xfrd->nsd->options->xfrd_reload_timeout;
xfrd->reload_timeout.tv_nsec = 0;
return;
}
/* cannot reload now, set that after the timeout a reload has to happen */
xfrd->reload_handler.timeout = &xfrd->reload_timeout;
}
static void
xfrd_handle_reload(netio_type *ATTR_UNUSED(netio),
netio_handler_type *handler, netio_event_types_type event_types)
{
/* reload timeout */
assert(event_types & NETIO_EVENT_TIMEOUT);
/* timeout wait period after this request is sent */
handler->timeout = NULL;
xfrd->reload_timeout.tv_sec = xfrd_time() +
xfrd->nsd->options->xfrd_reload_timeout;
xfrd->need_to_send_reload = 1;
xfrd->ipc_handler.event_types |= NETIO_EVENT_WRITE;
}
void
xfrd_handle_passed_packet(buffer_type* packet, int acl_num)
{
uint8_t qnamebuf[MAXDOMAINLEN];
uint16_t qtype, qclass;
const dname_type* dname;
region_type* tempregion = region_create(xalloc, free);
xfrd_zone_t* zone;
buffer_skip(packet, QHEADERSZ);
if(!packet_read_query_section(packet, qnamebuf, &qtype, &qclass)) {
region_destroy(tempregion);
return; /* drop bad packet */
}
dname = dname_make(tempregion, qnamebuf, 1);
DEBUG(DEBUG_XFRD,1, (LOG_INFO, "xfrd: got passed packet for %s, acl "
"%d", dname_to_string(dname,0), acl_num));
/* find the zone */
zone = (xfrd_zone_t*)rbtree_search(xfrd->zones, dname);
if(!zone) {
log_msg(LOG_INFO, "xfrd: incoming packet for unknown zone %s",
dname_to_string(dname,0));
region_destroy(tempregion);
return; /* drop packet for unknown zone */
}
region_destroy(tempregion);
/* handle */
if(OPCODE(packet) == OPCODE_NOTIFY) {
xfrd_soa_t soa;
int have_soa = 0;
int next;
/* get serial from a SOA */
if(ANCOUNT(packet) == 1 && packet_skip_dname(packet) &&
xfrd_parse_soa_info(packet, &soa)) {
have_soa = 1;
}
if(xfrd_handle_incoming_notify(zone, have_soa?&soa:NULL)) {
if(zone->zone_handler.fd == -1
&& zone->tcp_conn == -1 &&
!zone->tcp_waiting && !zone->udp_waiting) {
xfrd_set_refresh_now(zone);
}
}
next = find_same_master_notify(zone, acl_num);
if(next != -1) {
zone->next_master = next;
DEBUG(DEBUG_XFRD,1, (LOG_INFO,
"xfrd: notify set next master to query %d",
next));
}
}
else {
/* TODO handle incoming IXFR udp reply via port 53 */
}
}
static int
xfrd_handle_incoming_notify(xfrd_zone_t* zone, xfrd_soa_t* soa)
{
if(soa && zone->soa_disk_acquired && zone->state != xfrd_zone_expired &&
compare_serial(ntohl(soa->serial),ntohl(zone->soa_disk.serial)) <= 0)
{
DEBUG(DEBUG_XFRD,1, (LOG_INFO,
"xfrd: ignored notify %s %u old serial, zone valid "
"(soa disk serial %u)", zone->apex_str,
ntohl(soa->serial),
ntohl(zone->soa_disk.serial)));
return 0; /* ignore notify with old serial, we have a valid zone */
}
if(soa == 0) {
zone->soa_notified.serial = 0;
}
else if (zone->soa_notified_acquired == 0 ||
zone->soa_notified.serial == 0 ||
compare_serial(ntohl(soa->serial),
ntohl(zone->soa_notified.serial)) > 0)
{
zone->soa_notified = *soa;
}
zone->soa_notified_acquired = xfrd_time();
if(zone->state == xfrd_zone_ok) {
xfrd_set_zone_state(zone, xfrd_zone_refreshing);
}
/* transfer right away */
VERBOSITY(1, (LOG_INFO, "Handle incoming notify for zone %s",
zone->apex_str));
return 1;
}
static int
find_same_master_notify(xfrd_zone_t* zone, int acl_num_nfy)
{
acl_options_t* nfy_acl = acl_find_num(
zone->zone_options->allow_notify, acl_num_nfy);
int num = 0;
acl_options_t* master = zone->zone_options->request_xfr;
if(!nfy_acl)
return -1;
while(master)
{
if(acl_same_host(nfy_acl, master))
return num;
master = master->next;
num++;
}
return -1;
}
void
xfrd_check_failed_updates()
{
/* see if updates have not come through */
xfrd_zone_t* zone;
RBTREE_FOR(zone, xfrd_zone_t*, xfrd->zones)
{
/* zone has a disk soa, and no nsd soa or a different nsd soa */
if(zone->soa_disk_acquired != 0 &&
(zone->soa_nsd_acquired == 0 ||
zone->soa_disk.serial != zone->soa_nsd.serial))
{
if(zone->soa_disk_acquired <
xfrd->reload_cmd_last_sent)
{
/* this zone should have been loaded, since its disk
soa time is before the time of the reload cmd. */
xfrd_soa_t dumped_soa = zone->soa_disk;
log_msg(LOG_ERR, "xfrd: zone %s: soa serial %u "
"update failed, restarting "
"transfer (notified zone)",
zone->apex_str, ntohl(zone->soa_disk.serial));
/* revert the soa; it has not been acquired properly */
zone->soa_disk_acquired = zone->soa_nsd_acquired;
zone->soa_disk = zone->soa_nsd;
/* pretend we are notified with disk soa.
This will cause a refetch of the data, and reload. */
xfrd_handle_incoming_notify(zone, &dumped_soa);
xfrd_set_timer_refresh(zone);
} else if(zone->soa_disk_acquired >= xfrd->reload_cmd_last_sent) {
/* this zone still has to be loaded,
make sure reload is set to be sent. */
if(xfrd->need_to_send_reload == 0 &&
xfrd->reload_handler.timeout == NULL) {
log_msg(LOG_ERR, "xfrd: zone %s: needs "
"to be loaded. reload lost? "
"try again", zone->apex_str);
xfrd_set_reload_timeout();
}
}
}
}
}
void
xfrd_prepare_zones_for_reload()
{
xfrd_zone_t* zone;
RBTREE_FOR(zone, xfrd_zone_t*, xfrd->zones)
{
/* zone has a disk soa, and no nsd soa or a different nsd soa */
if(zone->soa_disk_acquired != 0 &&
(zone->soa_nsd_acquired == 0 ||
zone->soa_disk.serial != zone->soa_nsd.serial))
{
if(zone->soa_disk_acquired == xfrd_time()) {
/* antedate by one second.
* this makes sure that the zone time is before
* reload, so that check_failed_zones() is
* certain of the result.
*/
zone->soa_disk_acquired--;
}
}
}
}
struct buffer*
xfrd_get_temp_buffer()
{
return xfrd->packet;
}
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