bin/named/server.c

	server.c revision 72fb946eb082b1ae161c7b14f9f3d26fbd1c3caf
/*
 * Copyright (C) 1999  Internet Software Consortium.
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND INTERNET SOFTWARE CONSORTIUM DISCLAIMS
 * ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL INTERNET SOFTWARE
 * CONSORTIUM BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
 * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
 * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
 * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
 * SOFTWARE.
 */

#include <config.h>

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>

#include <isc/assertions.h>
#include <isc/error.h>
#include <isc/mem.h>
#include <isc/task.h>
#include <isc/thread.h>
#include <isc/result.h>
#include <isc/socket.h>
#include <isc/timer.h>

#include <dns/types.h>
#include <dns/result.h>
#include <dns/name.h>
#include <dns/fixedname.h>
#include <dns/rdata.h>
#include <dns/rdatalist.h>
#include <dns/rdataset.h>
#include <dns/rdatasetiter.h>
#include <dns/compress.h>
#include <dns/db.h>
#include <dns/dbtable.h>
#include <dns/message.h>

#include <sys/types.h>
#include <sys/socket.h>

#include <netinet/in.h>

#include <arpa/inet.h>

#include "confparser.h"
#include "udpclient.h"
#include "tcpclient.h"

typedef struct dbinfo {
    dns_db_t *      db;
    ISC_LINK(struct dbinfo) link;
} dbinfo;

isc_mem_t *         mctx;
isc_boolean_t           want_stats = ISC_FALSE;
static char         dbtype[128];
static dns_dbtable_t *      dbtable;
static ISC_LIST(dbinfo)     dbs;
static dbinfo *         cache_dbi;

static inline isc_boolean_t
CHECKRESULT(dns_result_t result, char *msg)
{
    if ((result) != DNS_R_SUCCESS) {
        printf("%s: %s\n", (msg), dns_result_totext(result));
        return (ISC_TRUE);
    }

    return (ISC_FALSE);
}

/*
 * This is in bin/tests/wire_test.c, but should be in a debugging library.
 */
extern dns_result_t
printmessage(dns_message_t *);

#define MAX_RDATASETS 25

static dns_result_t
resolve_packet(isc_mem_t *mctx, dns_message_t *query, isc_buffer_t *target) {
    dns_message_t *message;
    dns_result_t result, dbresult;
    dns_name_t *qname, *fname;
    dns_fixedname_t foundname;
    dns_rdataset_t *rds, *rdataset, rdatasets[MAX_RDATASETS];
    unsigned int nrdatasets = 0;
    dns_dbnode_t *node;
    dns_db_t *db;
    dns_rdatasetiter_t *rdsiter;
    dns_rdatatype_t type;
    isc_boolean_t possibly_auth = ISC_FALSE;

    message = NULL;
    result = dns_message_create(mctx, &message, DNS_MESSAGE_INTENTRENDER);
    CHECKRESULT(result, "dns_message_create failed");

    message->id = query->id;
    message->rcode = dns_rcode_noerror;
    message->flags = query->flags;
    message->flags |= DNS_MESSAGEFLAG_QR;

    /*
     * XXX This is a total and disgusting hack.  We need a way to add
     * a copy of a rdataset and a name to the new message, but for now
     * I'll just steal the one from the existing query message, and
     * make certain the query is not destroyed before our message is.
     */
    result = dns_message_firstname(query, DNS_SECTION_QUESTION);
    if (result != DNS_R_SUCCESS)
        return (result);
    qname = NULL;
    dns_message_currentname(query, DNS_SECTION_QUESTION, &qname);
    rds = ISC_LIST_HEAD(qname->list);
    if (rds == NULL)
        return (DNS_R_UNEXPECTED);
    type = rds->type;

    dns_message_addname(message, qname, DNS_SECTION_QUESTION);

    result = printmessage(message);
    INSIST(result == DNS_R_SUCCESS);  /* XXX not in a real server */

    /*
     * Find a database to answer the query from.
     */
    db = NULL;
    result = dns_dbtable_find(dbtable, qname, &db);
    if (result != DNS_R_SUCCESS && result != DNS_R_PARTIALMATCH) {
        printf("could not find a dbtable: %s\n",
               dns_result_totext(result));
        message->rcode = dns_rcode_servfail;
        goto render;
    }

    /*
     * Now look for an answer in the database.
     */
    dns_fixedname_init(&foundname);
    fname = dns_fixedname_name(&foundname);
    rdataset = &rdatasets[nrdatasets++];
    dns_rdataset_init(rdataset);
    node = NULL;
    dbresult = dns_db_find(db, qname, NULL, type, 0, 0, &node, fname,
                   rdataset);
    switch (dbresult) {
    case DNS_R_SUCCESS:
    case DNS_R_DNAME:
    case DNS_R_CNAME:
        possibly_auth = ISC_TRUE;
        break;
    case DNS_R_GLUE:
    case DNS_R_ZONECUT:
    case DNS_R_DELEGATION:
        break;
    case DNS_R_NXRDATASET:
        if (dns_db_iszone(db))
            message->flags |= DNS_MESSAGEFLAG_AA;
        dns_db_detachnode(db, &node);
        dns_db_detach(&db);
                goto render;
    case DNS_R_NXDOMAIN:
        if (dns_db_iszone(db))
            message->flags |= DNS_MESSAGEFLAG_AA;
        dns_db_detach(&db);
                message->rcode = dns_rcode_nxdomain;
                goto render;
    default:
        printf("%s\n", dns_result_totext(result));
        dns_db_detach(&db);
                message->rcode = dns_rcode_servfail;
                goto render;
    }

    if (dbresult == DNS_R_DELEGATION) {
        ISC_LIST_APPEND(fname->list, rdataset, link);
        dns_message_addname(message, fname, DNS_SECTION_AUTHORITY);
    } else if (type == dns_rdatatype_any) {
        rdsiter = NULL;
        result = dns_db_allrdatasets(db, node, NULL, 0, &rdsiter);
        if (result == DNS_R_SUCCESS)
            result = dns_rdatasetiter_first(rdsiter);
        while (result == DNS_R_SUCCESS) {
            dns_rdatasetiter_current(rdsiter, rdataset);
            ISC_LIST_APPEND(fname->list, rdataset, link);
            if (nrdatasets == MAX_RDATASETS) {
                result = DNS_R_NOSPACE;
            } else {
                rdataset = &rdatasets[nrdatasets++];
                dns_rdataset_init(rdataset);
                result = dns_rdatasetiter_next(rdsiter);
            }
        }
        if (result != DNS_R_NOMORE) {
            dns_db_detachnode(db, &node);
            dns_db_detach(&db);
            message->rcode = dns_rcode_servfail;
            goto render;
        }
        dns_message_addname(message, fname, DNS_SECTION_ANSWER);
    } else {
        ISC_LIST_APPEND(fname->list, rdataset, link);
        dns_message_addname(message, fname, DNS_SECTION_ANSWER);
    }

    if (dns_db_iszone(db) && possibly_auth)
        message->flags |= DNS_MESSAGEFLAG_AA;

    dns_db_detachnode(db, &node);
    dns_db_detach(&db);

 render:

    result = dns_message_renderbegin(message, target);
    if (result != DNS_R_SUCCESS)
        return (result);

    result = dns_message_rendersection(message, DNS_SECTION_QUESTION,
                       0, 0);
    if (result != DNS_R_SUCCESS)
        return (result);

    result = dns_message_rendersection(message, DNS_SECTION_ANSWER,
                       0, 0);
    if (result != DNS_R_SUCCESS)
        return (result);

    result = dns_message_rendersection(message, DNS_SECTION_AUTHORITY,
                       0, 0);
    if (result != DNS_R_SUCCESS)
        return (result);

    result = dns_message_rendersection(message, DNS_SECTION_ADDITIONAL,
                       0, 0);
    if (result != DNS_R_SUCCESS)
        return (result);

    result = dns_message_rendersection(message, DNS_SECTION_TSIG,
                       0, 0);
    if (result != DNS_R_SUCCESS)
        return (result);

    result = dns_message_renderend(message);

    dns_message_destroy(&message);

    return (DNS_R_SUCCESS);
}

/*
 * Process the wire format message given in r, and return a new packet to
 * transmit.
 *
 * Return of DNS_R_SUCCESS means r->base is a newly allocated region of
 * memory, and r->length is its length.  The actual for-transmit packet
 * begins at (r->length + reslen) to reserve (reslen) bytes at the front
 * of the packet for transmission specific details.
 */
static dns_result_t
dispatch(isc_mem_t *mctx, isc_region_t *rxr, unsigned int reslen)
{
    char t[512];
    isc_buffer_t source;
    isc_buffer_t target;
    dns_result_t result;
    isc_region_t txr;
    dns_message_t *message;

    /*
     * Set up the input buffer from the contents of the region passed
     * to us.
     */
    isc_buffer_init(&source, rxr->base, rxr->length,
            ISC_BUFFERTYPE_BINARY);
    isc_buffer_add(&source, rxr->length);

    message = NULL;
    result = dns_message_create(mctx, &message, DNS_MESSAGE_INTENTPARSE);
    if (CHECKRESULT(result, "dns_message_create failed")) {
        return (result);
    }

    result = dns_message_parse(message, &source);
    if (CHECKRESULT(result, "dns_message_parsed failed")) {
        dns_message_destroy(&message);
        return (result);
    }
    CHECKRESULT(result, "dns_message_parse failed");

    result = printmessage(message);
    if (CHECKRESULT(result, "printmessage failed")) {
        dns_message_destroy(&message);
        return (result);
    }

    isc_buffer_init(&target, t, sizeof(t), ISC_BUFFERTYPE_BINARY);
    result = resolve_packet(mctx, message, &target);
    if (result != DNS_R_SUCCESS) {
        dns_message_destroy(&message);
        return (result);
    }

    /*
     * Copy the reply out, adjusting for reslen
     */
    isc_buffer_used(&target, &txr);
    txr.base = isc_mem_get(mctx, txr.length + reslen);
    if (txr.base == NULL) {
        dns_message_destroy(&message);

        return (DNS_R_NOMEMORY);
    }

    memcpy(txr.base + reslen, t, txr.length);
    rxr->base = txr.base;
    rxr->length = txr.length + reslen;

    printf("Base == %p, length == %u\n", txr.base, txr.length);
    fflush(stdout);

    if (want_stats)
        isc_mem_stats(mctx, stdout);

    dns_message_destroy(&message);

    return (DNS_R_SUCCESS);
}

static dns_result_t
load(char *filename, char *origintext, isc_boolean_t cache) {
    dns_fixedname_t forigin;
    dns_name_t *origin;
    dns_result_t result;
    isc_buffer_t source;
    size_t len;
    dbinfo *dbi;

    dbi = isc_mem_get(mctx, sizeof *dbi);
    if (dbi == NULL)
        return (DNS_R_NOMEMORY);
    dbi->db = NULL;

    len = strlen(origintext);
    isc_buffer_init(&source, origintext, len, ISC_BUFFERTYPE_TEXT);
    isc_buffer_add(&source, len);
    dns_fixedname_init(&forigin);
    origin = dns_fixedname_name(&forigin);
    result = dns_name_fromtext(origin, &source, dns_rootname, ISC_FALSE,
                   NULL);
    if (result != DNS_R_SUCCESS)
        return (result);

    result = dns_db_create(mctx, dbtype, origin, cache, dns_rdataclass_in,
                   0, NULL, &dbi->db);
    if (result != DNS_R_SUCCESS) {
        isc_mem_put(mctx, dbi, sizeof *dbi);
        return (result);
    }

    printf("loading %s (%s)\n", filename, origintext);
    result = dns_db_load(dbi->db, filename);
    if (result != DNS_R_SUCCESS) {
        dns_db_detach(&dbi->db);
        isc_mem_put(mctx, dbi, sizeof *dbi);
        return (result);
    }
    printf("loaded\n");

    if (cache) {
        INSIST(cache_dbi == NULL);
        dns_dbtable_adddefault(dbtable, dbi->db);
        cache_dbi = dbi;
    } else {
        if (dns_dbtable_add(dbtable, dbi->db) != DNS_R_SUCCESS) {
            dns_db_detach(&dbi->db);
            isc_mem_put(mctx, dbi, sizeof *dbi);
            return (result);
        }
    }
    ISC_LIST_APPEND(dbs, dbi, link);

    return (DNS_R_SUCCESS);
}

static void
unload_all(void) {
    dbinfo *dbi, *dbi_next;

    for (dbi = ISC_LIST_HEAD(dbs); dbi != NULL; dbi = dbi_next) {
        dbi_next = ISC_LIST_NEXT(dbi, link);
        if (dns_db_iszone(dbi->db))
            dns_dbtable_remove(dbtable, dbi->db);
        else {
            INSIST(dbi == cache_dbi);
            dns_dbtable_removedefault(dbtable);
            cache_dbi = NULL;
        }
        dns_db_detach(&dbi->db);
        ISC_LIST_UNLINK(dbs, dbi, link);
        isc_mem_put(mctx, dbi, sizeof *dbi);
    }
}

int
main(int argc, char *argv[])
{
    isc_taskmgr_t *manager = NULL;
    unsigned int workers;
    isc_socketmgr_t *socketmgr;
    isc_socket_t *so0, *so1;
    isc_sockaddr_t sockaddr;
    unsigned int addrlen;
    udp_listener_t *ludp;
    tcp_listener_t *ltcp;
    int ch;
    char *origintext;
    dns_result_t result;

#if 0 /* brister */
    isc_cfgctx_t *configctx = NULL;
    const char *conffile = "/etc/named.conf"; /* XXX hardwired */
#endif

    RUNTIME_CHECK(isc_mem_create(0, 0, &mctx) == ISC_R_SUCCESS);
    RUNTIME_CHECK(dns_dbtable_create(mctx, dns_rdataclass_in, &dbtable) ==
              DNS_R_SUCCESS);
    strcpy(dbtype, "rbt");

    /*+ XXX */
    while ((ch = getopt(argc, argv, "c:d:z:s")) != -1) {
        switch (ch) {
        case 'c':
            result = load(optarg, ".", ISC_TRUE);
            if (result != DNS_R_SUCCESS)
                printf("%s\n", dns_result_totext(result));
            break;
        case 'd':
            strcpy(dbtype, optarg);
            break;
        case 'z':
            origintext = strrchr(optarg, '/');
            if (origintext == NULL)
                origintext = optarg;
            else
                origintext++;   /* Skip '/'. */
            result = load(optarg, origintext, ISC_FALSE);
            if (result != DNS_R_SUCCESS)
                printf("%s\n", dns_result_totext(result));
            break;
        case 's':
            want_stats = ISC_TRUE;
            break;
        }
    }

    argc -= optind;
    argv += optind;

    if (argc > 1)
        fprintf(stderr, "ignoring extra command line arguments\n");

    /*- XXX */

    memset(&sockaddr, 0, sizeof(sockaddr));
    sockaddr.type.sin.sin_port = htons(5544);
    addrlen = sizeof(struct sockaddr_in);

    workers = 2;
    printf("%d workers\n", workers);

#if 0 /* brister */
    parser_init();
    RUNTIME_CHECK(parse_configuration(conffile, mctx, &configctx) ==
              ISC_R_SUCCESS);
#endif

    RUNTIME_CHECK(isc_taskmgr_create(mctx, workers, 0, &manager) ==
              ISC_R_SUCCESS);

    socketmgr = NULL;
    RUNTIME_CHECK(isc_socketmgr_create(mctx, &socketmgr) == ISC_R_SUCCESS);

    /*
     * open up a UDP socket
     */
    so0 = NULL;
    memset(&sockaddr, 0, sizeof(sockaddr));
    sockaddr.type.sin.sin_family = AF_INET;
    sockaddr.type.sin.sin_port = htons(5544);
    addrlen = sizeof(struct sockaddr_in);
    RUNTIME_CHECK(isc_socket_create(socketmgr, isc_socket_udp, &so0) ==
              ISC_R_SUCCESS);
    RUNTIME_CHECK(isc_socket_bind(so0, &sockaddr,
                      (int)addrlen) == ISC_R_SUCCESS);

    ludp = udp_listener_allocate(mctx, workers);
    RUNTIME_CHECK(udp_listener_start(ludp, so0, manager,
                     workers, workers, 0,
                     dispatch) == ISC_R_SUCCESS);

    if (want_stats)
        isc_mem_stats(mctx, stdout);

    /*
     * open up a TCP socket
     */
    so1 = NULL;
    memset(&sockaddr, 0, sizeof(sockaddr));
    sockaddr.type.sin.sin_family = AF_INET;
    sockaddr.type.sin.sin_port = htons(5544);
    addrlen = sizeof(struct sockaddr_in);
    RUNTIME_CHECK(isc_socket_create(socketmgr, isc_socket_tcp, &so1) ==
              ISC_R_SUCCESS);
    RUNTIME_CHECK(isc_socket_bind(so1, &sockaddr,
                      (int)addrlen) == ISC_R_SUCCESS);

    ltcp = tcp_listener_allocate(mctx, workers);
    RUNTIME_CHECK(tcp_listener_start(ltcp, so1, manager,
                     workers, workers, 0,
                     dispatch) == ISC_R_SUCCESS);

    if (want_stats)
        isc_mem_stats(mctx, stdout);

    /*
     * XXX Need to set up a condition variable here, and wait on it.
     * For now, just semi-busy loop.
     */
    for (;;)
        sleep(10);

    unload_all();
    dns_dbtable_detach(&dbtable);

    printf("Destroying socket manager\n");
    isc_socketmgr_destroy(&socketmgr);

    printf("Destroying task manager\n");
    isc_taskmgr_destroy(&manager);

    if (want_stats)
        isc_mem_stats(mctx, stdout);
    isc_mem_destroy(&mctx);

    return (0);
}