/* * Copyright (C) Internet Systems Consortium, Inc. ("ISC") * * SPDX-License-Identifier: MPL-2.0 * * 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 https://mozilla.org/MPL/2.0/. * * See the COPYRIGHT file distributed with this work for additional * information regarding copyright ownership. */ /*! \file */ #include #include #include #include #include #include #include #include /* Required for HP/UX (and others?) */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include /* * Incoming AXFR and IXFR. */ /*% * It would be non-sensical (or at least obtuse) to use FAIL() with an * ISC_R_SUCCESS code, but the test is there to keep the Solaris compiler * from complaining about "end-of-loop code not reached". */ #define FAIL(code) \ do { \ result = (code); \ if (result != ISC_R_SUCCESS) \ goto failure; \ } while (0) #define CHECK(op) \ do { \ result = (op); \ if (result != ISC_R_SUCCESS) \ goto failure; \ } while (0) /*% * The states of the *XFR state machine. We handle both IXFR and AXFR * with a single integrated state machine because they cannot be distinguished * immediately - an AXFR response to an IXFR request can only be detected * when the first two (2) response RRs have already been received. */ typedef enum { XFRST_SOAQUERY, XFRST_GOTSOA, XFRST_INITIALSOA, XFRST_FIRSTDATA, XFRST_IXFR_DELSOA, XFRST_IXFR_DEL, XFRST_IXFR_ADDSOA, XFRST_IXFR_ADD, XFRST_IXFR_END, XFRST_AXFR, XFRST_AXFR_END } xfrin_state_t; /*% * Incoming zone transfer context. */ struct dns_xfrin_ctx { unsigned int magic; isc_mem_t *mctx; dns_zone_t *zone; isc_refcount_t references; isc_nm_t *netmgr; isc_refcount_t connects; /*%< Connect in progress */ isc_refcount_t sends; /*%< Send in progress */ isc_refcount_t recvs; /*%< Receive in progress */ atomic_bool shuttingdown; isc_result_t shutdown_result; dns_name_t name; /*%< Name of zone to transfer */ dns_rdataclass_t rdclass; dns_messageid_t id; /*% * Requested transfer type (dns_rdatatype_axfr or * dns_rdatatype_ixfr). The actual transfer type * may differ due to IXFR->AXFR fallback. */ dns_rdatatype_t reqtype; isc_sockaddr_t primaryaddr; isc_sockaddr_t sourceaddr; isc_nmhandle_t *handle; isc_nmhandle_t *readhandle; isc_nmhandle_t *sendhandle; /*% Buffer for IXFR/AXFR request message */ isc_buffer_t qbuffer; unsigned char qbuffer_data[512]; /*% * Whether the zone originally had a database attached at the time this * transfer context was created. Used by xfrin_destroy() when making * logging decisions. */ bool zone_had_db; dns_db_t *db; dns_dbversion_t *ver; dns_diff_t diff; /*%< Pending database changes */ int difflen; /*%< Number of pending tuples */ xfrin_state_t state; uint32_t end_serial; bool is_ixfr; unsigned int nmsg; /*%< Number of messages recvd */ unsigned int nrecs; /*%< Number of records recvd */ uint64_t nbytes; /*%< Number of bytes received */ unsigned int maxrecords; /*%< The maximum number of * records set for the zone */ isc_time_t start; /*%< Start time of the transfer */ isc_time_t end; /*%< End time of the transfer */ dns_tsigkey_t *tsigkey; /*%< Key used to create TSIG */ isc_buffer_t *lasttsig; /*%< The last TSIG */ dst_context_t *tsigctx; /*%< TSIG verification context */ unsigned int sincetsig; /*%< recvd since the last TSIG */ dns_transport_t *transport; dns_xfrindone_t done; /*% * AXFR- and IXFR-specific data. Only one is used at a time * according to the is_ixfr flag, so this could be a union, * but keeping them separate makes it a bit simpler to clean * things up when destroying the context. */ dns_rdatacallbacks_t axfr; struct { uint32_t request_serial; uint32_t current_serial; dns_journal_t *journal; } ixfr; dns_rdata_t firstsoa; unsigned char *firstsoa_data; isc_tlsctx_cache_t *tlsctx_cache; isc_timer_t *max_time_timer; isc_timer_t *max_idle_timer; }; #define XFRIN_MAGIC ISC_MAGIC('X', 'f', 'r', 'I') #define VALID_XFRIN(x) ISC_MAGIC_VALID(x, XFRIN_MAGIC) /**************************************************************************/ /* * Forward declarations. */ static void xfrin_create(isc_mem_t *mctx, dns_zone_t *zone, dns_db_t *db, isc_nm_t *netmgr, dns_name_t *zonename, dns_rdataclass_t rdclass, dns_rdatatype_t reqtype, const isc_sockaddr_t *primaryaddr, const isc_sockaddr_t *sourceaddr, dns_tsigkey_t *tsigkey, dns_transport_t *transport, isc_tlsctx_cache_t *tlsctx_cache, dns_xfrin_ctx_t **xfrp); static isc_result_t axfr_init(dns_xfrin_ctx_t *xfr); static isc_result_t axfr_makedb(dns_xfrin_ctx_t *xfr, dns_db_t **dbp); static isc_result_t axfr_putdata(dns_xfrin_ctx_t *xfr, dns_diffop_t op, dns_name_t *name, dns_ttl_t ttl, dns_rdata_t *rdata); static isc_result_t axfr_apply(dns_xfrin_ctx_t *xfr); static isc_result_t axfr_commit(dns_xfrin_ctx_t *xfr); static isc_result_t axfr_finalize(dns_xfrin_ctx_t *xfr); static isc_result_t ixfr_init(dns_xfrin_ctx_t *xfr); static isc_result_t ixfr_apply(dns_xfrin_ctx_t *xfr); static isc_result_t ixfr_putdata(dns_xfrin_ctx_t *xfr, dns_diffop_t op, dns_name_t *name, dns_ttl_t ttl, dns_rdata_t *rdata); static isc_result_t ixfr_commit(dns_xfrin_ctx_t *xfr); static isc_result_t xfr_rr(dns_xfrin_ctx_t *xfr, dns_name_t *name, uint32_t ttl, dns_rdata_t *rdata); static isc_result_t xfrin_start(dns_xfrin_ctx_t *xfr); static void xfrin_connect_done(isc_nmhandle_t *handle, isc_result_t result, void *cbarg); static isc_result_t xfrin_send_request(dns_xfrin_ctx_t *xfr); static void xfrin_send_done(isc_nmhandle_t *handle, isc_result_t result, void *cbarg); static void xfrin_recv_done(isc_nmhandle_t *handle, isc_result_t result, isc_region_t *region, void *cbarg); static void xfrin_destroy(dns_xfrin_ctx_t *xfr); static void xfrin_timedout(struct isc_task *, struct isc_event *); static void xfrin_idledout(struct isc_task *, struct isc_event *); static void xfrin_fail(dns_xfrin_ctx_t *xfr, isc_result_t result, const char *msg); static isc_result_t render(dns_message_t *msg, isc_mem_t *mctx, isc_buffer_t *buf); static void xfrin_logv(int level, const char *zonetext, const isc_sockaddr_t *primaryaddr, const char *fmt, va_list ap) ISC_FORMAT_PRINTF(4, 0); static void xfrin_log1(int level, const char *zonetext, const isc_sockaddr_t *primaryaddr, const char *fmt, ...) ISC_FORMAT_PRINTF(4, 5); static void xfrin_log(dns_xfrin_ctx_t *xfr, int level, const char *fmt, ...) ISC_FORMAT_PRINTF(3, 4); /**************************************************************************/ /* * AXFR handling */ static isc_result_t axfr_init(dns_xfrin_ctx_t *xfr) { isc_result_t result; xfr->is_ixfr = false; if (xfr->db != NULL) { dns_db_detach(&xfr->db); } CHECK(axfr_makedb(xfr, &xfr->db)); dns_rdatacallbacks_init(&xfr->axfr); CHECK(dns_db_beginload(xfr->db, &xfr->axfr)); result = ISC_R_SUCCESS; failure: return (result); } static isc_result_t axfr_makedb(dns_xfrin_ctx_t *xfr, dns_db_t **dbp) { isc_result_t result; result = dns_db_create(xfr->mctx, /* XXX */ "rbt", /* XXX guess */ &xfr->name, dns_dbtype_zone, xfr->rdclass, 0, NULL, /* XXX guess */ dbp); if (result == ISC_R_SUCCESS) { dns_zone_rpz_enable_db(xfr->zone, *dbp); dns_zone_catz_enable_db(xfr->zone, *dbp); } return (result); } static isc_result_t axfr_putdata(dns_xfrin_ctx_t *xfr, dns_diffop_t op, dns_name_t *name, dns_ttl_t ttl, dns_rdata_t *rdata) { isc_result_t result; dns_difftuple_t *tuple = NULL; if (rdata->rdclass != xfr->rdclass) { return (DNS_R_BADCLASS); } CHECK(dns_zone_checknames(xfr->zone, name, rdata)); CHECK(dns_difftuple_create(xfr->diff.mctx, op, name, ttl, rdata, &tuple)); dns_diff_append(&xfr->diff, &tuple); if (++xfr->difflen > 100) { CHECK(axfr_apply(xfr)); } result = ISC_R_SUCCESS; failure: return (result); } /* * Store a set of AXFR RRs in the database. */ static isc_result_t axfr_apply(dns_xfrin_ctx_t *xfr) { isc_result_t result; uint64_t records; CHECK(dns_diff_load(&xfr->diff, xfr->axfr.add, xfr->axfr.add_private)); xfr->difflen = 0; dns_diff_clear(&xfr->diff); if (xfr->maxrecords != 0U) { result = dns_db_getsize(xfr->db, xfr->ver, &records, NULL); if (result == ISC_R_SUCCESS && records > xfr->maxrecords) { result = DNS_R_TOOMANYRECORDS; goto failure; } } result = ISC_R_SUCCESS; failure: return (result); } static isc_result_t axfr_commit(dns_xfrin_ctx_t *xfr) { isc_result_t result; CHECK(axfr_apply(xfr)); CHECK(dns_db_endload(xfr->db, &xfr->axfr)); CHECK(dns_zone_verifydb(xfr->zone, xfr->db, NULL)); result = ISC_R_SUCCESS; failure: return (result); } static isc_result_t axfr_finalize(dns_xfrin_ctx_t *xfr) { isc_result_t result; CHECK(dns_zone_replacedb(xfr->zone, xfr->db, true)); result = ISC_R_SUCCESS; failure: return (result); } /**************************************************************************/ /* * IXFR handling */ static isc_result_t ixfr_init(dns_xfrin_ctx_t *xfr) { isc_result_t result; char *journalfile = NULL; if (xfr->reqtype != dns_rdatatype_ixfr) { xfrin_log(xfr, ISC_LOG_NOTICE, "got incremental response to AXFR request"); return (DNS_R_FORMERR); } xfr->is_ixfr = true; INSIST(xfr->db != NULL); xfr->difflen = 0; journalfile = dns_zone_getjournal(xfr->zone); if (journalfile != NULL) { CHECK(dns_journal_open(xfr->mctx, journalfile, DNS_JOURNAL_CREATE, &xfr->ixfr.journal)); } result = ISC_R_SUCCESS; failure: return (result); } static isc_result_t ixfr_putdata(dns_xfrin_ctx_t *xfr, dns_diffop_t op, dns_name_t *name, dns_ttl_t ttl, dns_rdata_t *rdata) { isc_result_t result; dns_difftuple_t *tuple = NULL; if (rdata->rdclass != xfr->rdclass) { return (DNS_R_BADCLASS); } if (op == DNS_DIFFOP_ADD) { CHECK(dns_zone_checknames(xfr->zone, name, rdata)); } CHECK(dns_difftuple_create(xfr->diff.mctx, op, name, ttl, rdata, &tuple)); dns_diff_append(&xfr->diff, &tuple); if (++xfr->difflen > 100) { CHECK(ixfr_apply(xfr)); } result = ISC_R_SUCCESS; failure: return (result); } /* * Apply a set of IXFR changes to the database. */ static isc_result_t ixfr_apply(dns_xfrin_ctx_t *xfr) { isc_result_t result; uint64_t records; if (xfr->ver == NULL) { CHECK(dns_db_newversion(xfr->db, &xfr->ver)); if (xfr->ixfr.journal != NULL) { CHECK(dns_journal_begin_transaction(xfr->ixfr.journal)); } } CHECK(dns_diff_apply(&xfr->diff, xfr->db, xfr->ver)); if (xfr->maxrecords != 0U) { result = dns_db_getsize(xfr->db, xfr->ver, &records, NULL); if (result == ISC_R_SUCCESS && records > xfr->maxrecords) { result = DNS_R_TOOMANYRECORDS; goto failure; } } if (xfr->ixfr.journal != NULL) { result = dns_journal_writediff(xfr->ixfr.journal, &xfr->diff); if (result != ISC_R_SUCCESS) { goto failure; } } dns_diff_clear(&xfr->diff); xfr->difflen = 0; result = ISC_R_SUCCESS; failure: return (result); } static isc_result_t ixfr_commit(dns_xfrin_ctx_t *xfr) { isc_result_t result; CHECK(ixfr_apply(xfr)); if (xfr->ver != NULL) { CHECK(dns_zone_verifydb(xfr->zone, xfr->db, xfr->ver)); /* XXX enter ready-to-commit state here */ if (xfr->ixfr.journal != NULL) { CHECK(dns_journal_commit(xfr->ixfr.journal)); } dns_db_closeversion(xfr->db, &xfr->ver, true); dns_zone_markdirty(xfr->zone); } result = ISC_R_SUCCESS; failure: return (result); } /**************************************************************************/ /* * Common AXFR/IXFR protocol code */ /* * Handle a single incoming resource record according to the current * state. */ static isc_result_t xfr_rr(dns_xfrin_ctx_t *xfr, dns_name_t *name, uint32_t ttl, dns_rdata_t *rdata) { isc_result_t result; xfr->nrecs++; if (rdata->type == dns_rdatatype_none || dns_rdatatype_ismeta(rdata->type)) { char buf[64]; dns_rdatatype_format(rdata->type, buf, sizeof(buf)); xfrin_log(xfr, ISC_LOG_NOTICE, "Unexpected %s record in zone transfer", buf); FAIL(DNS_R_FORMERR); } /* * Immediately reject the entire transfer if the RR that is currently * being processed is an SOA record that is not placed at the zone * apex. */ if (rdata->type == dns_rdatatype_soa && !dns_name_equal(&xfr->name, name)) { char namebuf[DNS_NAME_FORMATSIZE]; dns_name_format(name, namebuf, sizeof(namebuf)); xfrin_log(xfr, ISC_LOG_DEBUG(3), "SOA name mismatch: '%s'", namebuf); FAIL(DNS_R_NOTZONETOP); } redo: switch (xfr->state) { case XFRST_SOAQUERY: if (rdata->type != dns_rdatatype_soa) { xfrin_log(xfr, ISC_LOG_NOTICE, "non-SOA response to SOA query"); FAIL(DNS_R_FORMERR); } xfr->end_serial = dns_soa_getserial(rdata); if (!DNS_SERIAL_GT(xfr->end_serial, xfr->ixfr.request_serial) && !dns_zone_isforced(xfr->zone)) { xfrin_log(xfr, ISC_LOG_DEBUG(3), "requested serial %u, " "primary has %u, not updating", xfr->ixfr.request_serial, xfr->end_serial); FAIL(DNS_R_UPTODATE); } xfr->state = XFRST_GOTSOA; break; case XFRST_GOTSOA: /* * Skip other records in the answer section. */ break; case XFRST_INITIALSOA: if (rdata->type != dns_rdatatype_soa) { xfrin_log(xfr, ISC_LOG_NOTICE, "first RR in zone transfer must be SOA"); FAIL(DNS_R_FORMERR); } /* * Remember the serial number in the initial SOA. * We need it to recognize the end of an IXFR. */ xfr->end_serial = dns_soa_getserial(rdata); if (xfr->reqtype == dns_rdatatype_ixfr && !DNS_SERIAL_GT(xfr->end_serial, xfr->ixfr.request_serial) && !dns_zone_isforced(xfr->zone)) { /* * This must be the single SOA record that is * sent when the current version on the primary * is not newer than the version in the request. */ xfrin_log(xfr, ISC_LOG_DEBUG(3), "requested serial %u, " "primary has %u, not updating", xfr->ixfr.request_serial, xfr->end_serial); FAIL(DNS_R_UPTODATE); } xfr->firstsoa = *rdata; if (xfr->firstsoa_data != NULL) { isc_mem_free(xfr->mctx, xfr->firstsoa_data); } xfr->firstsoa_data = isc_mem_allocate(xfr->mctx, rdata->length); memcpy(xfr->firstsoa_data, rdata->data, rdata->length); xfr->firstsoa.data = xfr->firstsoa_data; xfr->state = XFRST_FIRSTDATA; break; case XFRST_FIRSTDATA: /* * If the transfer begins with one SOA record, it is an AXFR, * if it begins with two SOAs, it is an IXFR. */ if (xfr->reqtype == dns_rdatatype_ixfr && rdata->type == dns_rdatatype_soa && xfr->ixfr.request_serial == dns_soa_getserial(rdata)) { xfrin_log(xfr, ISC_LOG_DEBUG(3), "got incremental response"); CHECK(ixfr_init(xfr)); xfr->state = XFRST_IXFR_DELSOA; } else { xfrin_log(xfr, ISC_LOG_DEBUG(3), "got nonincremental response"); CHECK(axfr_init(xfr)); xfr->state = XFRST_AXFR; } goto redo; case XFRST_IXFR_DELSOA: INSIST(rdata->type == dns_rdatatype_soa); CHECK(ixfr_putdata(xfr, DNS_DIFFOP_DEL, name, ttl, rdata)); xfr->state = XFRST_IXFR_DEL; break; case XFRST_IXFR_DEL: if (rdata->type == dns_rdatatype_soa) { uint32_t soa_serial = dns_soa_getserial(rdata); xfr->state = XFRST_IXFR_ADDSOA; xfr->ixfr.current_serial = soa_serial; goto redo; } CHECK(ixfr_putdata(xfr, DNS_DIFFOP_DEL, name, ttl, rdata)); break; case XFRST_IXFR_ADDSOA: INSIST(rdata->type == dns_rdatatype_soa); CHECK(ixfr_putdata(xfr, DNS_DIFFOP_ADD, name, ttl, rdata)); xfr->state = XFRST_IXFR_ADD; break; case XFRST_IXFR_ADD: if (rdata->type == dns_rdatatype_soa) { uint32_t soa_serial = dns_soa_getserial(rdata); if (soa_serial == xfr->end_serial) { CHECK(ixfr_commit(xfr)); xfr->state = XFRST_IXFR_END; break; } else if (soa_serial != xfr->ixfr.current_serial) { xfrin_log(xfr, ISC_LOG_NOTICE, "IXFR out of sync: " "expected serial %u, got %u", xfr->ixfr.current_serial, soa_serial); FAIL(DNS_R_FORMERR); } else { CHECK(ixfr_commit(xfr)); xfr->state = XFRST_IXFR_DELSOA; goto redo; } } if (rdata->type == dns_rdatatype_ns && dns_name_iswildcard(name)) { FAIL(DNS_R_INVALIDNS); } CHECK(ixfr_putdata(xfr, DNS_DIFFOP_ADD, name, ttl, rdata)); break; case XFRST_AXFR: /* * Old BINDs sent cross class A records for non IN classes. */ if (rdata->type == dns_rdatatype_a && rdata->rdclass != xfr->rdclass && xfr->rdclass != dns_rdataclass_in) { break; } CHECK(axfr_putdata(xfr, DNS_DIFFOP_ADD, name, ttl, rdata)); if (rdata->type == dns_rdatatype_soa) { /* * Use dns_rdata_compare instead of memcmp to * allow for case differences. */ if (dns_rdata_compare(rdata, &xfr->firstsoa) != 0) { xfrin_log(xfr, ISC_LOG_NOTICE, "start and ending SOA records " "mismatch"); FAIL(DNS_R_FORMERR); } CHECK(axfr_commit(xfr)); xfr->state = XFRST_AXFR_END; break; } break; case XFRST_AXFR_END: case XFRST_IXFR_END: FAIL(DNS_R_EXTRADATA); FALLTHROUGH; default: UNREACHABLE(); } result = ISC_R_SUCCESS; failure: return (result); } isc_result_t dns_xfrin_create(dns_zone_t *zone, dns_rdatatype_t xfrtype, const isc_sockaddr_t *primaryaddr, const isc_sockaddr_t *sourceaddr, dns_tsigkey_t *tsigkey, dns_transport_t *transport, isc_tlsctx_cache_t *tlsctx_cache, isc_mem_t *mctx, isc_nm_t *netmgr, dns_xfrindone_t done, dns_xfrin_ctx_t **xfrp) { dns_name_t *zonename = dns_zone_getorigin(zone); dns_xfrin_ctx_t *xfr = NULL; isc_result_t result; dns_db_t *db = NULL; REQUIRE(xfrp != NULL && *xfrp == NULL); REQUIRE(done != NULL); REQUIRE(isc_sockaddr_getport(primaryaddr) != 0); (void)dns_zone_getdb(zone, &db); if (xfrtype == dns_rdatatype_soa || xfrtype == dns_rdatatype_ixfr) { REQUIRE(db != NULL); } xfrin_create(mctx, zone, db, netmgr, zonename, dns_zone_getclass(zone), xfrtype, primaryaddr, sourceaddr, tsigkey, transport, tlsctx_cache, &xfr); if (db != NULL) { xfr->zone_had_db = true; } xfr->done = done; isc_refcount_init(&xfr->references, 1); /* * Set *xfrp now, before calling xfrin_start(). Asynchronous * netmgr processing could cause the 'done' callback to run in * another thread before we reached the end of the present * function. In that case, if *xfrp hadn't already been * attached, the 'done' function would be unable to detach it. */ *xfrp = xfr; result = xfrin_start(xfr); if (result != ISC_R_SUCCESS) { atomic_store(&xfr->shuttingdown, true); xfr->shutdown_result = result; dns_xfrin_detach(xfrp); } if (db != NULL) { dns_db_detach(&db); } if (result != ISC_R_SUCCESS) { char zonetext[DNS_NAME_MAXTEXT + 32]; dns_zone_name(zone, zonetext, sizeof(zonetext)); xfrin_log1(ISC_LOG_ERROR, zonetext, primaryaddr, "zone transfer setup failed"); } return (result); } static void xfrin_cancelio(dns_xfrin_ctx_t *xfr); static void xfrin_timedout(struct isc_task *task, struct isc_event *event) { UNUSED(task); dns_xfrin_ctx_t *xfr = event->ev_arg; REQUIRE(VALID_XFRIN(xfr)); xfrin_fail(xfr, ISC_R_TIMEDOUT, "maximum transfer time exceeded"); isc_event_free(&event); } static void xfrin_idledout(struct isc_task *task, struct isc_event *event) { UNUSED(task); dns_xfrin_ctx_t *xfr = event->ev_arg; REQUIRE(VALID_XFRIN(xfr)); xfrin_fail(xfr, ISC_R_TIMEDOUT, "maximum idle time exceeded"); isc_event_free(&event); } void dns_xfrin_shutdown(dns_xfrin_ctx_t *xfr) { REQUIRE(VALID_XFRIN(xfr)); xfrin_fail(xfr, ISC_R_CANCELED, "shut down"); } void dns_xfrin_attach(dns_xfrin_ctx_t *source, dns_xfrin_ctx_t **target) { REQUIRE(VALID_XFRIN(source)); REQUIRE(target != NULL && *target == NULL); (void)isc_refcount_increment(&source->references); *target = source; } void dns_xfrin_detach(dns_xfrin_ctx_t **xfrp) { dns_xfrin_ctx_t *xfr = NULL; REQUIRE(xfrp != NULL && VALID_XFRIN(*xfrp)); xfr = *xfrp; *xfrp = NULL; if (isc_refcount_decrement(&xfr->references) == 1) { xfrin_destroy(xfr); } } static void xfrin_cancelio(dns_xfrin_ctx_t *xfr) { if (xfr->readhandle == NULL) { return; } isc_nm_cancelread(xfr->readhandle); /* The xfr->readhandle detach will happen in xfrin_recv_done callback */ } static void xfrin_reset(dns_xfrin_ctx_t *xfr) { REQUIRE(VALID_XFRIN(xfr)); xfrin_log(xfr, ISC_LOG_INFO, "resetting"); REQUIRE(xfr->readhandle == NULL); REQUIRE(xfr->sendhandle == NULL); if (xfr->lasttsig != NULL) { isc_buffer_free(&xfr->lasttsig); } dns_diff_clear(&xfr->diff); xfr->difflen = 0; if (xfr->ixfr.journal != NULL) { dns_journal_destroy(&xfr->ixfr.journal); } if (xfr->axfr.add_private != NULL) { (void)dns_db_endload(xfr->db, &xfr->axfr); } if (xfr->ver != NULL) { dns_db_closeversion(xfr->db, &xfr->ver, false); } } static void xfrin_fail(dns_xfrin_ctx_t *xfr, isc_result_t result, const char *msg) { /* Make sure only the first xfrin_fail() trumps */ if (atomic_compare_exchange_strong(&xfr->shuttingdown, &(bool){ false }, true)) { (void)isc_timer_reset(xfr->max_time_timer, isc_timertype_inactive, NULL, NULL, true); (void)isc_timer_reset(xfr->max_idle_timer, isc_timertype_inactive, NULL, NULL, true); if (result != DNS_R_UPTODATE && result != DNS_R_TOOMANYRECORDS) { xfrin_log(xfr, ISC_LOG_ERROR, "%s: %s", msg, isc_result_totext(result)); if (xfr->is_ixfr) { /* Pass special result code to force AXFR retry */ result = DNS_R_BADIXFR; } } xfrin_cancelio(xfr); /* * Close the journal. */ if (xfr->ixfr.journal != NULL) { dns_journal_destroy(&xfr->ixfr.journal); } if (xfr->done != NULL) { (xfr->done)(xfr->zone, result); xfr->done = NULL; } xfr->shutdown_result = result; } } static void xfrin_create(isc_mem_t *mctx, dns_zone_t *zone, dns_db_t *db, isc_nm_t *netmgr, dns_name_t *zonename, dns_rdataclass_t rdclass, dns_rdatatype_t reqtype, const isc_sockaddr_t *primaryaddr, const isc_sockaddr_t *sourceaddr, dns_tsigkey_t *tsigkey, dns_transport_t *transport, isc_tlsctx_cache_t *tlsctx_cache, dns_xfrin_ctx_t **xfrp) { dns_xfrin_ctx_t *xfr = NULL; dns_zonemgr_t *zmgr = dns_zone_getmgr(zone); isc_timermgr_t *timermgr = dns_zonemgr_gettimermgr(zmgr); isc_task_t *ztask = NULL; xfr = isc_mem_get(mctx, sizeof(*xfr)); *xfr = (dns_xfrin_ctx_t){ .netmgr = netmgr, .shutdown_result = ISC_R_UNSET, .rdclass = rdclass, .reqtype = reqtype, .id = (dns_messageid_t)isc_random16(), .maxrecords = dns_zone_getmaxrecords(zone), .primaryaddr = *primaryaddr, .sourceaddr = *sourceaddr, .firstsoa = DNS_RDATA_INIT, .magic = XFRIN_MAGIC }; isc_mem_attach(mctx, &xfr->mctx); dns_zone_iattach(zone, &xfr->zone); dns_name_init(&xfr->name, NULL); isc_refcount_init(&xfr->connects, 0); isc_refcount_init(&xfr->sends, 0); isc_refcount_init(&xfr->recvs, 0); atomic_init(&xfr->shuttingdown, false); if (db != NULL) { dns_db_attach(db, &xfr->db); } dns_diff_init(xfr->mctx, &xfr->diff); if (reqtype == dns_rdatatype_soa) { xfr->state = XFRST_SOAQUERY; } else { xfr->state = XFRST_INITIALSOA; } isc_time_now(&xfr->start); if (tsigkey != NULL) { dns_tsigkey_attach(tsigkey, &xfr->tsigkey); } if (transport != NULL) { dns_transport_attach(transport, &xfr->transport); } dns_name_dup(zonename, mctx, &xfr->name); INSIST(isc_sockaddr_pf(primaryaddr) == isc_sockaddr_pf(sourceaddr)); isc_sockaddr_setport(&xfr->sourceaddr, 0); /* * Reserve 2 bytes for TCP length at the beginning of the buffer. */ isc_buffer_init(&xfr->qbuffer, &xfr->qbuffer_data[2], sizeof(xfr->qbuffer_data) - 2); isc_tlsctx_cache_attach(tlsctx_cache, &xfr->tlsctx_cache); dns_zone_gettask(zone, &ztask); isc_timer_create(timermgr, isc_timertype_inactive, NULL, NULL, ztask, xfrin_timedout, xfr, &xfr->max_time_timer); isc_timer_create(timermgr, isc_timertype_inactive, NULL, NULL, ztask, xfrin_idledout, xfr, &xfr->max_idle_timer); isc_task_detach(&ztask); /* dns_zone_task() attaches to the task */ *xfrp = xfr; } static isc_result_t get_create_tlsctx(const dns_xfrin_ctx_t *xfr, isc_tlsctx_t **pctx, isc_tlsctx_client_session_cache_t **psess_cache) { isc_result_t result = ISC_R_FAILURE; isc_tlsctx_t *tlsctx = NULL, *found = NULL; isc_tls_cert_store_t *store = NULL, *found_store = NULL; isc_tlsctx_client_session_cache_t *sess_cache = NULL, *found_sess_cache = NULL; uint32_t tls_versions; const char *ciphers = NULL; bool prefer_server_ciphers; const uint16_t family = isc_sockaddr_pf(&xfr->primaryaddr) == PF_INET6 ? AF_INET6 : AF_INET; const char *tlsname = NULL; REQUIRE(psess_cache != NULL && *psess_cache == NULL); REQUIRE(pctx != NULL && *pctx == NULL); INSIST(xfr->transport != NULL); tlsname = dns_transport_get_tlsname(xfr->transport); INSIST(tlsname != NULL && *tlsname != '\0'); /* * Let's try to re-use the already created context. This way * we have a chance to resume the TLS session, bypassing the * full TLS handshake procedure, making establishing * subsequent TLS connections for XoT faster. */ result = isc_tlsctx_cache_find(xfr->tlsctx_cache, tlsname, isc_tlsctx_cache_tls, family, &found, &found_store, &found_sess_cache); if (result != ISC_R_SUCCESS) { const char *hostname = dns_transport_get_remote_hostname(xfr->transport); const char *ca_file = dns_transport_get_cafile(xfr->transport); const char *cert_file = dns_transport_get_certfile(xfr->transport); const char *key_file = dns_transport_get_keyfile(xfr->transport); char primary_addr_str[INET6_ADDRSTRLEN] = { 0 }; isc_netaddr_t primary_netaddr = { 0 }; bool hostname_ignore_subject; /* * So, no context exists. Let's create one using the * parameters from the configuration file and try to * store it for further reuse. */ result = isc_tlsctx_createclient(&tlsctx); if (result != ISC_R_SUCCESS) { goto failure; } tls_versions = dns_transport_get_tls_versions(xfr->transport); if (tls_versions != 0) { isc_tlsctx_set_protocols(tlsctx, tls_versions); } ciphers = dns_transport_get_ciphers(xfr->transport); if (ciphers != NULL) { isc_tlsctx_set_cipherlist(tlsctx, ciphers); } if (dns_transport_get_prefer_server_ciphers( xfr->transport, &prefer_server_ciphers)) { isc_tlsctx_prefer_server_ciphers(tlsctx, prefer_server_ciphers); } if (hostname != NULL || ca_file != NULL) { /* * The situation when 'found_store != NULL' while 'found * == NULL' might appear as there is one to many * relation between per transport TLS contexts and cert * stores. That is, there could be one store shared * between multiple contexts. */ if (found_store == NULL) { /* * 'ca_file' can equal 'NULL' here, in * that case the store with system-wide * CA certificates will be created, just * as planned. */ result = isc_tls_cert_store_create(ca_file, &store); if (result != ISC_R_SUCCESS) { goto failure; } } else { store = found_store; } INSIST(store != NULL); if (hostname == NULL) { /* * If CA bundle file is specified, but * hostname is not, then use the primary * IP address for validation, just like * dig does. */ INSIST(ca_file != NULL); isc_netaddr_fromsockaddr(&primary_netaddr, &xfr->primaryaddr); isc_netaddr_format(&primary_netaddr, primary_addr_str, sizeof(primary_addr_str)); hostname = primary_addr_str; } /* * According to RFC 8310, Subject field MUST NOT * be inspected when verifying hostname for DoT. * Only SubjectAltName must be checked. */ hostname_ignore_subject = true; result = isc_tlsctx_enable_peer_verification( tlsctx, false, store, hostname, hostname_ignore_subject); if (result != ISC_R_SUCCESS) { goto failure; } /* * Let's load client certificate and enable * Mutual TLS. We do that only in the case when * Strict TLS is enabled, because Mutual TLS is * an extension of it. */ if (cert_file != NULL) { INSIST(key_file != NULL); result = isc_tlsctx_load_certificate( tlsctx, key_file, cert_file); if (result != ISC_R_SUCCESS) { goto failure; } } } isc_tlsctx_enable_dot_client_alpn(tlsctx); isc_tlsctx_client_session_cache_create( xfr->mctx, tlsctx, ISC_TLSCTX_CLIENT_SESSION_CACHE_DEFAULT_SIZE, &sess_cache); found_store = NULL; result = isc_tlsctx_cache_add(xfr->tlsctx_cache, tlsname, isc_tlsctx_cache_tls, family, tlsctx, store, sess_cache, &found, &found_store, &found_sess_cache); if (result == ISC_R_EXISTS) { /* * It seems the entry has just been created from within * another thread while we were initialising * ours. Although this is unlikely, it could happen * after startup/re-initialisation. In such a case, * discard the new context and associated data and use * the already established one from now on. * * Such situation will not occur after the * initial 'warm-up', so it is not critical * performance-wise. */ INSIST(found != NULL); isc_tlsctx_free(&tlsctx); isc_tls_cert_store_free(&store); isc_tlsctx_client_session_cache_detach(&sess_cache); /* Let's return the data from the cache. */ *psess_cache = found_sess_cache; *pctx = found; } else { /* * Adding the fresh values into the cache has been * successful, let's return them */ INSIST(result == ISC_R_SUCCESS); *psess_cache = sess_cache; *pctx = tlsctx; } } else { /* * The cache lookup has been successful, let's return the * results. */ INSIST(result == ISC_R_SUCCESS); *psess_cache = found_sess_cache; *pctx = found; } return (ISC_R_SUCCESS); failure: if (tlsctx != NULL) { isc_tlsctx_free(&tlsctx); } /* * The 'found_store' is being managed by the TLS context * cache. Thus, we should keep it as it is, as it will get * destroyed alongside the cache. As there is one store per * multiple TLS contexts, we need to handle store deletion in a * special way. */ if (store != NULL && store != found_store) { isc_tls_cert_store_free(&store); } return (result); } static isc_result_t xfrin_start(dns_xfrin_ctx_t *xfr) { isc_result_t result; dns_xfrin_ctx_t *connect_xfr = NULL; dns_transport_type_t transport_type = DNS_TRANSPORT_TCP; isc_tlsctx_t *tlsctx = NULL; isc_tlsctx_client_session_cache_t *sess_cache = NULL; isc_interval_t interval; isc_time_t next; (void)isc_refcount_increment0(&xfr->connects); dns_xfrin_attach(xfr, &connect_xfr); if (xfr->transport != NULL) { transport_type = dns_transport_get_type(xfr->transport); } /* Set the maximum timer */ isc_interval_set(&interval, dns_zone_getmaxxfrin(xfr->zone), 0); isc_time_nowplusinterval(&next, &interval); result = isc_timer_reset(xfr->max_time_timer, isc_timertype_once, &next, NULL, true); RUNTIME_CHECK(result == ISC_R_SUCCESS); /* Set the idle timer */ isc_interval_set(&interval, dns_zone_getidlein(xfr->zone), 0); isc_time_nowplusinterval(&next, &interval); result = isc_timer_reset(xfr->max_idle_timer, isc_timertype_once, &next, NULL, true); RUNTIME_CHECK(result == ISC_R_SUCCESS); /* * XXX: timeouts are hard-coded to 30 seconds; this needs to be * configurable. */ switch (transport_type) { case DNS_TRANSPORT_TCP: isc_nm_tcpdnsconnect(xfr->netmgr, &xfr->sourceaddr, &xfr->primaryaddr, xfrin_connect_done, connect_xfr, 30000, 0); break; case DNS_TRANSPORT_TLS: { result = get_create_tlsctx(xfr, &tlsctx, &sess_cache); if (result != ISC_R_SUCCESS) { goto failure; } INSIST(tlsctx != NULL); isc_nm_tlsdnsconnect(xfr->netmgr, &xfr->sourceaddr, &xfr->primaryaddr, xfrin_connect_done, connect_xfr, 30000, 0, tlsctx, sess_cache); } break; default: UNREACHABLE(); } return (ISC_R_SUCCESS); failure: isc_refcount_decrement0(&xfr->connects); dns_xfrin_detach(&connect_xfr); return (result); } /* XXX the resolver could use this, too */ static isc_result_t render(dns_message_t *msg, isc_mem_t *mctx, isc_buffer_t *buf) { dns_compress_t cctx; bool cleanup_cctx = false; isc_result_t result; CHECK(dns_compress_init(&cctx, -1, mctx)); cleanup_cctx = true; CHECK(dns_message_renderbegin(msg, &cctx, buf)); CHECK(dns_message_rendersection(msg, DNS_SECTION_QUESTION, 0)); CHECK(dns_message_rendersection(msg, DNS_SECTION_ANSWER, 0)); CHECK(dns_message_rendersection(msg, DNS_SECTION_AUTHORITY, 0)); CHECK(dns_message_rendersection(msg, DNS_SECTION_ADDITIONAL, 0)); CHECK(dns_message_renderend(msg)); result = ISC_R_SUCCESS; failure: if (cleanup_cctx) { dns_compress_invalidate(&cctx); } return (result); } /* * A connection has been established. */ static void xfrin_connect_done(isc_nmhandle_t *handle, isc_result_t result, void *cbarg) { dns_xfrin_ctx_t *xfr = (dns_xfrin_ctx_t *)cbarg; char sourcetext[ISC_SOCKADDR_FORMATSIZE]; char signerbuf[DNS_NAME_FORMATSIZE]; const char *signer = "", *sep = ""; isc_sockaddr_t sockaddr; dns_zonemgr_t *zmgr = NULL; REQUIRE(VALID_XFRIN(xfr)); isc_refcount_decrement0(&xfr->connects); if (atomic_load(&xfr->shuttingdown)) { result = ISC_R_SHUTTINGDOWN; } if (result != ISC_R_SUCCESS) { xfrin_fail(xfr, result, "failed to connect"); goto failure; } result = isc_nm_xfr_checkperm(handle); if (result != ISC_R_SUCCESS) { xfrin_fail(xfr, result, "connected but unable to transfer"); goto failure; } zmgr = dns_zone_getmgr(xfr->zone); if (zmgr != NULL) { dns_zonemgr_unreachabledel(zmgr, &xfr->primaryaddr, &xfr->sourceaddr); } xfr->handle = handle; sockaddr = isc_nmhandle_peeraddr(handle); isc_sockaddr_format(&sockaddr, sourcetext, sizeof(sourcetext)); if (xfr->tsigkey != NULL && xfr->tsigkey->key != NULL) { dns_name_format(dst_key_name(xfr->tsigkey->key), signerbuf, sizeof(signerbuf)); sep = " TSIG "; signer = signerbuf; } xfrin_log(xfr, ISC_LOG_INFO, "connected using %s%s%s", sourcetext, sep, signer); result = xfrin_send_request(xfr); if (result != ISC_R_SUCCESS) { xfrin_fail(xfr, result, "connected but unable to send"); } failure: switch (result) { case ISC_R_SUCCESS: break; case ISC_R_NETDOWN: case ISC_R_HOSTDOWN: case ISC_R_NETUNREACH: case ISC_R_HOSTUNREACH: case ISC_R_CONNREFUSED: case ISC_R_TIMEDOUT: /* * Add the server to unreachable primaries table if * the server has a permanent networking error or * the connection attempt as timed out. */ zmgr = dns_zone_getmgr(xfr->zone); if (zmgr != NULL) { isc_time_t now; TIME_NOW(&now); dns_zonemgr_unreachableadd(zmgr, &xfr->primaryaddr, &xfr->sourceaddr, &now); } break; default: /* Retry sooner than in 10 minutes */ break; } dns_xfrin_detach(&xfr); } /* * Convert a tuple into a dns_name_t suitable for inserting * into the given dns_message_t. */ static isc_result_t tuple2msgname(dns_difftuple_t *tuple, dns_message_t *msg, dns_name_t **target) { isc_result_t result; dns_rdata_t *rdata = NULL; dns_rdatalist_t *rdl = NULL; dns_rdataset_t *rds = NULL; dns_name_t *name = NULL; REQUIRE(target != NULL && *target == NULL); CHECK(dns_message_gettemprdata(msg, &rdata)); dns_rdata_init(rdata); dns_rdata_clone(&tuple->rdata, rdata); CHECK(dns_message_gettemprdatalist(msg, &rdl)); dns_rdatalist_init(rdl); rdl->type = tuple->rdata.type; rdl->rdclass = tuple->rdata.rdclass; rdl->ttl = tuple->ttl; ISC_LIST_APPEND(rdl->rdata, rdata, link); CHECK(dns_message_gettemprdataset(msg, &rds)); CHECK(dns_rdatalist_tordataset(rdl, rds)); CHECK(dns_message_gettempname(msg, &name)); dns_name_clone(&tuple->name, name); ISC_LIST_APPEND(name->list, rds, link); *target = name; return (ISC_R_SUCCESS); failure: if (rds != NULL) { dns_rdataset_disassociate(rds); dns_message_puttemprdataset(msg, &rds); } if (rdl != NULL) { ISC_LIST_UNLINK(rdl->rdata, rdata, link); dns_message_puttemprdatalist(msg, &rdl); } if (rdata != NULL) { dns_message_puttemprdata(msg, &rdata); } return (result); } /* * Build an *XFR request and send its length prefix. */ static isc_result_t xfrin_send_request(dns_xfrin_ctx_t *xfr) { isc_result_t result; isc_region_t region; dns_rdataset_t *qrdataset = NULL; dns_message_t *msg = NULL; dns_difftuple_t *soatuple = NULL; dns_name_t *qname = NULL; dns_dbversion_t *ver = NULL; dns_name_t *msgsoaname = NULL; dns_xfrin_ctx_t *send_xfr = NULL; /* Create the request message */ dns_message_create(xfr->mctx, DNS_MESSAGE_INTENTRENDER, &msg); CHECK(dns_message_settsigkey(msg, xfr->tsigkey)); /* Create a name for the question section. */ CHECK(dns_message_gettempname(msg, &qname)); dns_name_clone(&xfr->name, qname); /* Formulate the question and attach it to the question name. */ CHECK(dns_message_gettemprdataset(msg, &qrdataset)); dns_rdataset_makequestion(qrdataset, xfr->rdclass, xfr->reqtype); ISC_LIST_APPEND(qname->list, qrdataset, link); qrdataset = NULL; dns_message_addname(msg, qname, DNS_SECTION_QUESTION); qname = NULL; if (xfr->reqtype == dns_rdatatype_ixfr) { /* Get the SOA and add it to the authority section. */ /* XXX is using the current version the right thing? */ dns_db_currentversion(xfr->db, &ver); CHECK(dns_db_createsoatuple(xfr->db, ver, xfr->mctx, DNS_DIFFOP_EXISTS, &soatuple)); xfr->ixfr.request_serial = dns_soa_getserial(&soatuple->rdata); xfr->ixfr.current_serial = xfr->ixfr.request_serial; xfrin_log(xfr, ISC_LOG_DEBUG(3), "requesting IXFR for serial %u", xfr->ixfr.request_serial); CHECK(tuple2msgname(soatuple, msg, &msgsoaname)); dns_message_addname(msg, msgsoaname, DNS_SECTION_AUTHORITY); } else if (xfr->reqtype == dns_rdatatype_soa) { CHECK(dns_db_getsoaserial(xfr->db, NULL, &xfr->ixfr.request_serial)); } xfr->id++; xfr->nmsg = 0; xfr->nrecs = 0; xfr->nbytes = 0; isc_time_now(&xfr->start); msg->id = xfr->id; if (xfr->tsigctx != NULL) { dst_context_destroy(&xfr->tsigctx); } CHECK(render(msg, xfr->mctx, &xfr->qbuffer)); /* * Free the last tsig, if there is one. */ if (xfr->lasttsig != NULL) { isc_buffer_free(&xfr->lasttsig); } /* * Save the query TSIG and don't let message_destroy free it. */ CHECK(dns_message_getquerytsig(msg, xfr->mctx, &xfr->lasttsig)); isc_buffer_usedregion(&xfr->qbuffer, ®ion); INSIST(region.length <= 65535); dns_xfrin_attach(xfr, &send_xfr); isc_nmhandle_attach(send_xfr->handle, &xfr->sendhandle); isc_refcount_increment0(&send_xfr->sends); isc_nm_send(xfr->handle, ®ion, xfrin_send_done, send_xfr); failure: if (qname != NULL) { dns_message_puttempname(msg, &qname); } if (qrdataset != NULL) { dns_message_puttemprdataset(msg, &qrdataset); } if (msg != NULL) { dns_message_detach(&msg); } if (soatuple != NULL) { dns_difftuple_free(&soatuple); } if (ver != NULL) { dns_db_closeversion(xfr->db, &ver, false); } return (result); } static void xfrin_send_done(isc_nmhandle_t *handle, isc_result_t result, void *cbarg) { dns_xfrin_ctx_t *xfr = (dns_xfrin_ctx_t *)cbarg; dns_xfrin_ctx_t *recv_xfr = NULL; REQUIRE(VALID_XFRIN(xfr)); isc_refcount_decrement0(&xfr->sends); if (atomic_load(&xfr->shuttingdown)) { result = ISC_R_SHUTTINGDOWN; } CHECK(result); xfrin_log(xfr, ISC_LOG_DEBUG(3), "sent request data"); dns_xfrin_attach(xfr, &recv_xfr); isc_nmhandle_attach(handle, &recv_xfr->readhandle); isc_refcount_increment0(&recv_xfr->recvs); isc_nm_read(recv_xfr->handle, xfrin_recv_done, recv_xfr); failure: if (result != ISC_R_SUCCESS) { xfrin_fail(xfr, result, "failed sending request data"); } isc_nmhandle_detach(&xfr->sendhandle); dns_xfrin_detach(&xfr); /* send_xfr */ } static void xfrin_recv_done(isc_nmhandle_t *handle, isc_result_t result, isc_region_t *region, void *cbarg) { dns_xfrin_ctx_t *xfr = (dns_xfrin_ctx_t *)cbarg; dns_message_t *msg = NULL; dns_name_t *name = NULL; const dns_name_t *tsigowner = NULL; isc_buffer_t buffer; isc_sockaddr_t peer; REQUIRE(VALID_XFRIN(xfr)); isc_refcount_decrement0(&xfr->recvs); if (atomic_load(&xfr->shuttingdown)) { result = ISC_R_SHUTTINGDOWN; } /* Stop the idle timer */ (void)isc_timer_reset(xfr->max_idle_timer, isc_timertype_inactive, NULL, NULL, true); CHECK(result); xfrin_log(xfr, ISC_LOG_DEBUG(7), "received %u bytes", region->length); dns_message_create(xfr->mctx, DNS_MESSAGE_INTENTPARSE, &msg); CHECK(dns_message_settsigkey(msg, xfr->tsigkey)); CHECK(dns_message_setquerytsig(msg, xfr->lasttsig)); msg->tsigctx = xfr->tsigctx; xfr->tsigctx = NULL; dns_message_setclass(msg, xfr->rdclass); if (xfr->nmsg > 0) { msg->tcp_continuation = 1; } isc_buffer_init(&buffer, region->base, region->length); isc_buffer_add(&buffer, region->length); peer = isc_nmhandle_peeraddr(handle); result = dns_message_parse(msg, &buffer, DNS_MESSAGEPARSE_PRESERVEORDER); if (result == ISC_R_SUCCESS) { dns_message_logpacket(msg, "received message from", &peer, DNS_LOGCATEGORY_XFER_IN, DNS_LOGMODULE_XFER_IN, ISC_LOG_DEBUG(10), xfr->mctx); } else { xfrin_log(xfr, ISC_LOG_DEBUG(10), "dns_message_parse: %s", isc_result_totext(result)); } if (result != ISC_R_SUCCESS || msg->rcode != dns_rcode_noerror || msg->opcode != dns_opcode_query || msg->rdclass != xfr->rdclass || msg->id != xfr->id) { if (result == ISC_R_SUCCESS && msg->rcode != dns_rcode_noerror) { result = dns_result_fromrcode(msg->rcode); } else if (result == ISC_R_SUCCESS && msg->opcode != dns_opcode_query) { result = DNS_R_UNEXPECTEDOPCODE; } else if (result == ISC_R_SUCCESS && msg->rdclass != xfr->rdclass) { result = DNS_R_BADCLASS; } else if (result == ISC_R_SUCCESS || result == DNS_R_NOERROR) { result = DNS_R_UNEXPECTEDID; } if (xfr->reqtype == dns_rdatatype_axfr || xfr->reqtype == dns_rdatatype_soa) { goto failure; } xfrin_log(xfr, ISC_LOG_DEBUG(3), "got %s, retrying with AXFR", isc_result_totext(result)); try_axfr: isc_nmhandle_detach(&xfr->readhandle); dns_message_detach(&msg); xfrin_reset(xfr); xfr->reqtype = dns_rdatatype_soa; xfr->state = XFRST_SOAQUERY; result = xfrin_start(xfr); if (result != ISC_R_SUCCESS) { xfrin_fail(xfr, result, "failed setting up socket"); } dns_xfrin_detach(&xfr); /* recv_xfr */ return; } /* * The question section should exist for SOA and in the first * message of a AXFR or IXFR response. The question section * may exist in the 2nd and subsequent messages in a AXFR or * IXFR response. If the question section exists it should * match the question that was sent. */ if (msg->counts[DNS_SECTION_QUESTION] > 1) { xfrin_log(xfr, ISC_LOG_NOTICE, "too many questions (%u)", msg->counts[DNS_SECTION_QUESTION]); result = DNS_R_FORMERR; goto failure; } if ((xfr->state == XFRST_SOAQUERY || xfr->state == XFRST_INITIALSOA) && msg->counts[DNS_SECTION_QUESTION] != 1) { xfrin_log(xfr, ISC_LOG_NOTICE, "missing question section"); result = DNS_R_FORMERR; goto failure; } for (result = dns_message_firstname(msg, DNS_SECTION_QUESTION); result == ISC_R_SUCCESS; result = dns_message_nextname(msg, DNS_SECTION_QUESTION)) { dns_rdataset_t *rds = NULL; name = NULL; dns_message_currentname(msg, DNS_SECTION_QUESTION, &name); if (!dns_name_equal(name, &xfr->name)) { result = DNS_R_FORMERR; xfrin_log(xfr, ISC_LOG_NOTICE, "question name mismatch"); goto failure; } rds = ISC_LIST_HEAD(name->list); INSIST(rds != NULL); if (rds->type != xfr->reqtype) { result = DNS_R_FORMERR; xfrin_log(xfr, ISC_LOG_NOTICE, "question type mismatch"); goto failure; } if (rds->rdclass != xfr->rdclass) { result = DNS_R_FORMERR; xfrin_log(xfr, ISC_LOG_NOTICE, "question class mismatch"); goto failure; } } if (result != ISC_R_NOMORE) { goto failure; } /* * Does the server know about IXFR? If it doesn't we will get * a message with a empty answer section or a potentially a CNAME / * DNAME, the later is handled by xfr_rr() which will return FORMERR * if the first RR in the answer section is not a SOA record. */ if (xfr->reqtype == dns_rdatatype_ixfr && xfr->state == XFRST_INITIALSOA && msg->counts[DNS_SECTION_ANSWER] == 0) { xfrin_log(xfr, ISC_LOG_DEBUG(3), "empty answer section, retrying with AXFR"); goto try_axfr; } if (xfr->reqtype == dns_rdatatype_soa && (msg->flags & DNS_MESSAGEFLAG_AA) == 0) { FAIL(DNS_R_NOTAUTHORITATIVE); } result = dns_message_checksig(msg, dns_zone_getview(xfr->zone)); if (result != ISC_R_SUCCESS) { xfrin_log(xfr, ISC_LOG_DEBUG(3), "TSIG check failed: %s", isc_result_totext(result)); goto failure; } for (result = dns_message_firstname(msg, DNS_SECTION_ANSWER); result == ISC_R_SUCCESS; result = dns_message_nextname(msg, DNS_SECTION_ANSWER)) { dns_rdataset_t *rds = NULL; name = NULL; dns_message_currentname(msg, DNS_SECTION_ANSWER, &name); for (rds = ISC_LIST_HEAD(name->list); rds != NULL; rds = ISC_LIST_NEXT(rds, link)) { for (result = dns_rdataset_first(rds); result == ISC_R_SUCCESS; result = dns_rdataset_next(rds)) { dns_rdata_t rdata = DNS_RDATA_INIT; dns_rdataset_current(rds, &rdata); CHECK(xfr_rr(xfr, name, rds->ttl, &rdata)); } } } if (result != ISC_R_NOMORE) { goto failure; } if (dns_message_gettsig(msg, &tsigowner) != NULL) { /* * Reset the counter. */ xfr->sincetsig = 0; /* * Free the last tsig, if there is one. */ if (xfr->lasttsig != NULL) { isc_buffer_free(&xfr->lasttsig); } /* * Update the last tsig pointer. */ CHECK(dns_message_getquerytsig(msg, xfr->mctx, &xfr->lasttsig)); } else if (dns_message_gettsigkey(msg) != NULL) { xfr->sincetsig++; if (xfr->sincetsig > 100 || xfr->nmsg == 0 || xfr->state == XFRST_AXFR_END || xfr->state == XFRST_IXFR_END) { result = DNS_R_EXPECTEDTSIG; goto failure; } } /* * Update the number of messages received. */ xfr->nmsg++; /* * Update the number of bytes received. */ xfr->nbytes += buffer.used; /* * Take the context back. */ INSIST(xfr->tsigctx == NULL); xfr->tsigctx = msg->tsigctx; msg->tsigctx = NULL; switch (xfr->state) { case XFRST_GOTSOA: xfr->reqtype = dns_rdatatype_axfr; xfr->state = XFRST_INITIALSOA; CHECK(xfrin_send_request(xfr)); break; case XFRST_AXFR_END: CHECK(axfr_finalize(xfr)); FALLTHROUGH; case XFRST_IXFR_END: /* * Close the journal. */ if (xfr->ixfr.journal != NULL) { dns_journal_destroy(&xfr->ixfr.journal); } /* * Inform the caller we succeeded. */ if (xfr->done != NULL) { (xfr->done)(xfr->zone, ISC_R_SUCCESS); xfr->done = NULL; } atomic_store(&xfr->shuttingdown, true); (void)isc_timer_reset(xfr->max_time_timer, isc_timertype_inactive, NULL, NULL, true); xfr->shutdown_result = ISC_R_SUCCESS; break; default: /* * Read the next message. */ /* The readhandle is still attached */ /* The recv_xfr is still attached */ dns_message_detach(&msg); isc_refcount_increment0(&xfr->recvs); isc_nm_read(xfr->handle, xfrin_recv_done, xfr); isc_time_t next; isc_interval_t interval; isc_interval_set(&interval, dns_zone_getidlein(xfr->zone), 0); isc_time_nowplusinterval(&next, &interval); result = isc_timer_reset(xfr->max_idle_timer, isc_timertype_once, &next, NULL, true); RUNTIME_CHECK(result == ISC_R_SUCCESS); return; } failure: if (result != ISC_R_SUCCESS) { xfrin_fail(xfr, result, "failed while receiving responses"); } if (msg != NULL) { dns_message_detach(&msg); } isc_nmhandle_detach(&xfr->readhandle); dns_xfrin_detach(&xfr); /* recv_xfr */ } static void xfrin_destroy(dns_xfrin_ctx_t *xfr) { uint64_t msecs; uint64_t persec; const char *result_str; REQUIRE(VALID_XFRIN(xfr)); /* Safe-guards */ REQUIRE(atomic_load(&xfr->shuttingdown)); isc_refcount_destroy(&xfr->references); isc_refcount_destroy(&xfr->connects); isc_refcount_destroy(&xfr->recvs); isc_refcount_destroy(&xfr->sends); INSIST(xfr->shutdown_result != ISC_R_UNSET); /* * If we're called through dns_xfrin_detach() and are not * shutting down, we can't know what the transfer status is as * we are only called when the last reference is lost. */ result_str = isc_result_totext(xfr->shutdown_result); xfrin_log(xfr, ISC_LOG_INFO, "Transfer status: %s", result_str); /* * Calculate the length of time the transfer took, * and print a log message with the bytes and rate. */ isc_time_now(&xfr->end); msecs = isc_time_microdiff(&xfr->end, &xfr->start) / 1000; if (msecs == 0) { msecs = 1; } persec = (xfr->nbytes * 1000) / msecs; xfrin_log(xfr, ISC_LOG_INFO, "Transfer completed: %d messages, %d records, " "%" PRIu64 " bytes, " "%u.%03u secs (%u bytes/sec) (serial %u)", xfr->nmsg, xfr->nrecs, xfr->nbytes, (unsigned int)(msecs / 1000), (unsigned int)(msecs % 1000), (unsigned int)persec, xfr->end_serial); if (xfr->readhandle != NULL) { isc_nmhandle_detach(&xfr->readhandle); } if (xfr->sendhandle != NULL) { isc_nmhandle_detach(&xfr->sendhandle); } if (xfr->transport != NULL) { dns_transport_detach(&xfr->transport); } if (xfr->tsigkey != NULL) { dns_tsigkey_detach(&xfr->tsigkey); } if (xfr->lasttsig != NULL) { isc_buffer_free(&xfr->lasttsig); } dns_diff_clear(&xfr->diff); if (xfr->ixfr.journal != NULL) { dns_journal_destroy(&xfr->ixfr.journal); } if (xfr->axfr.add_private != NULL) { (void)dns_db_endload(xfr->db, &xfr->axfr); } if (xfr->tsigctx != NULL) { dst_context_destroy(&xfr->tsigctx); } if ((xfr->name.attributes & DNS_NAMEATTR_DYNAMIC) != 0) { dns_name_free(&xfr->name, xfr->mctx); } if (xfr->ver != NULL) { dns_db_closeversion(xfr->db, &xfr->ver, false); } if (xfr->db != NULL) { dns_db_detach(&xfr->db); } if (xfr->zone != NULL) { if (!xfr->zone_had_db && xfr->shutdown_result == ISC_R_SUCCESS && dns_zone_gettype(xfr->zone) == dns_zone_mirror) { dns_zone_log(xfr->zone, ISC_LOG_INFO, "mirror zone is now in use"); } xfrin_log(xfr, ISC_LOG_DEBUG(99), "freeing transfer context"); /* * xfr->zone must not be detached before xfrin_log() is called. */ dns_zone_idetach(&xfr->zone); } if (xfr->firstsoa_data != NULL) { isc_mem_free(xfr->mctx, xfr->firstsoa_data); } if (xfr->tlsctx_cache != NULL) { isc_tlsctx_cache_detach(&xfr->tlsctx_cache); } isc_timer_destroy(&xfr->max_idle_timer); isc_timer_destroy(&xfr->max_time_timer); isc_mem_putanddetach(&xfr->mctx, xfr, sizeof(*xfr)); } /* * Log incoming zone transfer messages in a format like * transfer of from
: */ static void xfrin_logv(int level, const char *zonetext, const isc_sockaddr_t *primaryaddr, const char *fmt, va_list ap) { char primarytext[ISC_SOCKADDR_FORMATSIZE]; char msgtext[2048]; isc_sockaddr_format(primaryaddr, primarytext, sizeof(primarytext)); vsnprintf(msgtext, sizeof(msgtext), fmt, ap); isc_log_write(dns_lctx, DNS_LOGCATEGORY_XFER_IN, DNS_LOGMODULE_XFER_IN, level, "transfer of '%s' from %s: %s", zonetext, primarytext, msgtext); } /* * Logging function for use when a xfrin_ctx_t has not yet been created. */ static void xfrin_log1(int level, const char *zonetext, const isc_sockaddr_t *primaryaddr, const char *fmt, ...) { va_list ap; if (!isc_log_wouldlog(dns_lctx, level)) { return; } va_start(ap, fmt); xfrin_logv(level, zonetext, primaryaddr, fmt, ap); va_end(ap); } /* * Logging function for use when there is a xfrin_ctx_t. */ static void xfrin_log(dns_xfrin_ctx_t *xfr, int level, const char *fmt, ...) { va_list ap; char zonetext[DNS_NAME_MAXTEXT + 32]; if (!isc_log_wouldlog(dns_lctx, level)) { return; } dns_zone_name(xfr->zone, zonetext, sizeof(zonetext)); va_start(ap, fmt); xfrin_logv(level, zonetext, &xfr->primaryaddr, fmt, ap); va_end(ap); }