コード例 #1
0
ファイル: kerberos5.c プロジェクト: 285858315/samba
krb5_error_code
_kdc_as_rep(krb5_context context,
	    krb5_kdc_configuration *config,
	    KDC_REQ *req,
	    const krb5_data *req_buffer,
	    krb5_data *reply,
	    const char *from,
	    struct sockaddr *from_addr,
	    int datagram_reply)
{
    KDC_REQ_BODY *b = &req->req_body;
    AS_REP rep;
    KDCOptions f = b->kdc_options;
    hdb_entry_ex *client = NULL, *server = NULL;
    HDB *clientdb;
    krb5_enctype setype, sessionetype;
    krb5_data e_data;
    EncTicketPart et;
    EncKDCRepPart ek;
    krb5_principal client_princ = NULL, server_princ = NULL;
    char *client_name = NULL, *server_name = NULL;
    krb5_error_code ret = 0;
    const char *e_text = NULL;
    krb5_crypto crypto;
    Key *ckey, *skey;
    EncryptionKey *reply_key = NULL, session_key;
    int flags = HDB_F_FOR_AS_REQ;
#ifdef PKINIT
    pk_client_params *pkp = NULL;
#endif

    memset(&rep, 0, sizeof(rep));
    memset(&session_key, 0, sizeof(session_key));
    krb5_data_zero(&e_data);

    ALLOC(rep.padata);
    rep.padata->len = 0;
    rep.padata->val = NULL;

    if (f.canonicalize)
	flags |= HDB_F_CANON;

    if(b->sname == NULL){
	ret = KRB5KRB_ERR_GENERIC;
	e_text = "No server in request";
    } else{
	ret = _krb5_principalname2krb5_principal (context,
						  &server_princ,
						  *(b->sname),
						  b->realm);
	if (ret == 0)
	    ret = krb5_unparse_name(context, server_princ, &server_name);
    }
    if (ret) {
	kdc_log(context, config, 0,
		"AS-REQ malformed server name from %s", from);
	goto out;
    }
    if(b->cname == NULL){
	ret = KRB5KRB_ERR_GENERIC;
	e_text = "No client in request";
    } else {
	ret = _krb5_principalname2krb5_principal (context,
						  &client_princ,
						  *(b->cname),
						  b->realm);
	if (ret)
	    goto out;

	ret = krb5_unparse_name(context, client_princ, &client_name);
    }
    if (ret) {
	kdc_log(context, config, 0,
		"AS-REQ malformed client name from %s", from);
	goto out;
    }

    kdc_log(context, config, 0, "AS-REQ %s from %s for %s",
	    client_name, from, server_name);

    /*
     *
     */

    if (_kdc_is_anonymous(context, client_princ)) {
	if (!b->kdc_options.request_anonymous) {
	    kdc_log(context, config, 0, "Anonymous ticket w/o anonymous flag");
	    ret = KRB5KDC_ERR_C_PRINCIPAL_UNKNOWN;
	    goto out;
	}
    } else if (b->kdc_options.request_anonymous) {
	kdc_log(context, config, 0,
		"Request for a anonymous ticket with non "
		"anonymous client name: %s", client_name);
	ret = KRB5KDC_ERR_C_PRINCIPAL_UNKNOWN;
	goto out;
    }

    /*
     *
     */

    ret = _kdc_db_fetch(context, config, client_princ,
			HDB_F_GET_CLIENT | flags, NULL,
			&clientdb, &client);
    if(ret == HDB_ERR_NOT_FOUND_HERE) {
	kdc_log(context, config, 5, "client %s does not have secrets at this KDC, need to proxy", client_name);
	goto out;
    } else if(ret){
	const char *msg = krb5_get_error_message(context, ret);
	kdc_log(context, config, 0, "UNKNOWN -- %s: %s", client_name, msg);
	krb5_free_error_message(context, msg);
	ret = KRB5KDC_ERR_C_PRINCIPAL_UNKNOWN;
	goto out;
    }
    ret = _kdc_db_fetch(context, config, server_princ,
			HDB_F_GET_SERVER|HDB_F_GET_KRBTGT | flags,
			NULL, NULL, &server);
    if(ret == HDB_ERR_NOT_FOUND_HERE) {
	kdc_log(context, config, 5, "target %s does not have secrets at this KDC, need to proxy", server_name);
	goto out;
    } else if(ret){
	const char *msg = krb5_get_error_message(context, ret);
	kdc_log(context, config, 0, "UNKNOWN -- %s: %s", server_name, msg);
	krb5_free_error_message(context, msg);
	ret = KRB5KDC_ERR_S_PRINCIPAL_UNKNOWN;
	goto out;
    }

    memset(&et, 0, sizeof(et));
    memset(&ek, 0, sizeof(ek));

    /*
     * Select a session enctype from the list of the crypto system
     * supported enctypes that is supported by the client and is one of
     * the enctype of the enctype of the service (likely krbtgt).
     *
     * The latter is used as a hint of what enctypes all KDC support,
     * to make sure a newer version of KDC won't generate a session
     * enctype that an older version of a KDC in the same realm can't
     * decrypt.
     */
    ret = _kdc_find_etype(context, config->as_use_strongest_session_key, FALSE,
			  client, b->etype.val, b->etype.len, &sessionetype,
			  NULL);
    if (ret) {
	kdc_log(context, config, 0,
		"Client (%s) from %s has no common enctypes with KDC "
		"to use for the session key",
		client_name, from);
	goto out;
    }
    /*
     * But if the KDC admin is paranoid and doesn't want to have "not
     * the best" enctypes on the krbtgt, lets save the best pick from
     * the client list and hope that that will work for any other
     * KDCs.
     */

    /*
     * Pre-auth processing
     */

    if(req->padata){
	int i;
	const PA_DATA *pa;
	int found_pa = 0;

	log_patypes(context, config, req->padata);

#ifdef PKINIT
	kdc_log(context, config, 5,
		"Looking for PKINIT pa-data -- %s", client_name);

	e_text = "No PKINIT PA found";

	i = 0;
	pa = _kdc_find_padata(req, &i, KRB5_PADATA_PK_AS_REQ);
	if (pa == NULL) {
	    i = 0;
	    pa = _kdc_find_padata(req, &i, KRB5_PADATA_PK_AS_REQ_WIN);
	}
	if (pa) {
	    char *client_cert = NULL;

	    ret = _kdc_pk_rd_padata(context, config, req, pa, client, &pkp);
	    if (ret) {
		ret = KRB5KRB_AP_ERR_BAD_INTEGRITY;
		kdc_log(context, config, 5,
			"Failed to decode PKINIT PA-DATA -- %s",
			client_name);
		goto ts_enc;
	    }
	    if (ret == 0 && pkp == NULL)
		goto ts_enc;

	    ret = _kdc_pk_check_client(context,
				       config,
				       clientdb,
				       client,
				       pkp,
				       &client_cert);
	    if (ret) {
		e_text = "PKINIT certificate not allowed to "
		    "impersonate principal";
		_kdc_pk_free_client_param(context, pkp);

		kdc_log(context, config, 0, "%s", e_text);
		pkp = NULL;
		goto out;
	    }

	    found_pa = 1;
	    et.flags.pre_authent = 1;
	    kdc_log(context, config, 0,
		    "PKINIT pre-authentication succeeded -- %s using %s",
		    client_name, client_cert);
	    free(client_cert);
	    if (pkp)
		goto preauth_done;
	}
    ts_enc:
#endif

	if (client->entry.flags.locked_out) {
	    ret = KRB5KDC_ERR_CLIENT_REVOKED;
	    kdc_log(context, config, 0,
		    "Client (%s) is locked out", client_name);
	    goto out;
	}

	kdc_log(context, config, 5, "Looking for ENC-TS pa-data -- %s",
		client_name);

	i = 0;
	e_text = "No ENC-TS found";
	while((pa = _kdc_find_padata(req, &i, KRB5_PADATA_ENC_TIMESTAMP))){
	    krb5_data ts_data;
	    PA_ENC_TS_ENC p;
	    size_t len;
	    EncryptedData enc_data;
	    Key *pa_key;
	    char *str;

	    found_pa = 1;

	    if (b->kdc_options.request_anonymous) {
		ret = KRB5KRB_AP_ERR_BAD_INTEGRITY;
		kdc_log(context, config, 0, "ENC-TS doesn't support anon");
		goto out;
	    }

	    ret = decode_EncryptedData(pa->padata_value.data,
				       pa->padata_value.length,
				       &enc_data,
				       &len);
	    if (ret) {
		ret = KRB5KRB_AP_ERR_BAD_INTEGRITY;
		kdc_log(context, config, 5, "Failed to decode PA-DATA -- %s",
			client_name);
		goto out;
	    }

	    ret = hdb_enctype2key(context, &client->entry,
				  enc_data.etype, &pa_key);
	    if(ret){
		char *estr;
		e_text = "No key matches pa-data";
		ret = KRB5KDC_ERR_ETYPE_NOSUPP;
		if(krb5_enctype_to_string(context, enc_data.etype, &estr))
		    estr = NULL;
		if(estr == NULL)
		    kdc_log(context, config, 5,
			    "No client key matching pa-data (%d) -- %s",
			    enc_data.etype, client_name);
		else
		    kdc_log(context, config, 5,
			    "No client key matching pa-data (%s) -- %s",
			    estr, client_name);
		free(estr);
		free_EncryptedData(&enc_data);

		continue;
	    }

	try_next_key:
	    ret = krb5_crypto_init(context, &pa_key->key, 0, &crypto);
	    if (ret) {
		const char *msg = krb5_get_error_message(context, ret);
		kdc_log(context, config, 0, "krb5_crypto_init failed: %s", msg);
		krb5_free_error_message(context, msg);
		free_EncryptedData(&enc_data);
		continue;
	    }

	    ret = krb5_decrypt_EncryptedData (context,
					      crypto,
					      KRB5_KU_PA_ENC_TIMESTAMP,
					      &enc_data,
					      &ts_data);
	    krb5_crypto_destroy(context, crypto);
	    /*
	     * Since the user might have several keys with the same
	     * enctype but with diffrent salting, we need to try all
	     * the keys with the same enctype.
	     */
	    if(ret){
		krb5_error_code ret2;
		const char *msg = krb5_get_error_message(context, ret);

		ret2 = krb5_enctype_to_string(context,
					      pa_key->key.keytype, &str);
		if (ret2)
		    str = NULL;
		kdc_log(context, config, 5,
			"Failed to decrypt PA-DATA -- %s "
			"(enctype %s) error %s",
			client_name, str ? str : "unknown enctype", msg);
		krb5_free_error_message(context, msg);
		free(str);

		if(hdb_next_enctype2key(context, &client->entry,
					enc_data.etype, &pa_key) == 0)
		    goto try_next_key;
		e_text = "Failed to decrypt PA-DATA";

		free_EncryptedData(&enc_data);

		if (clientdb->hdb_auth_status)
		    (clientdb->hdb_auth_status)(context, clientdb, client, HDB_AUTH_WRONG_PASSWORD);

		ret = KRB5KDC_ERR_PREAUTH_FAILED;
		continue;
	    }
	    free_EncryptedData(&enc_data);
	    ret = decode_PA_ENC_TS_ENC(ts_data.data,
				       ts_data.length,
				       &p,
				       &len);
	    krb5_data_free(&ts_data);
	    if(ret){
		e_text = "Failed to decode PA-ENC-TS-ENC";
		ret = KRB5KDC_ERR_PREAUTH_FAILED;
		kdc_log(context, config,
			5, "Failed to decode PA-ENC-TS_ENC -- %s",
			client_name);
		continue;
	    }
	    free_PA_ENC_TS_ENC(&p);
	    if (abs(kdc_time - p.patimestamp) > context->max_skew) {
		char client_time[100];

		krb5_format_time(context, p.patimestamp,
				 client_time, sizeof(client_time), TRUE);

 		ret = KRB5KRB_AP_ERR_SKEW;
 		kdc_log(context, config, 0,
			"Too large time skew, "
			"client time %s is out by %u > %u seconds -- %s",
			client_time,
			(unsigned)abs(kdc_time - p.patimestamp),
			context->max_skew,
			client_name);

		/*
		 * The following is needed to make windows clients to
		 * retry using the timestamp in the error message, if
		 * there is a e_text, they become unhappy.
		 */
		e_text = NULL;
		goto out;
	    }
	    et.flags.pre_authent = 1;

	    set_salt_padata(rep.padata, pa_key->salt);

	    reply_key = &pa_key->key;

	    ret = krb5_enctype_to_string(context, pa_key->key.keytype, &str);
	    if (ret)
		str = NULL;

	    kdc_log(context, config, 2,
		    "ENC-TS Pre-authentication succeeded -- %s using %s",
		    client_name, str ? str : "unknown enctype");
	    free(str);
	    break;
	}
#ifdef PKINIT
    preauth_done:
#endif
	if(found_pa == 0 && config->require_preauth)
	    goto use_pa;
	/* We come here if we found a pa-enc-timestamp, but if there
           was some problem with it, other than too large skew */
	if(found_pa && et.flags.pre_authent == 0){
	    kdc_log(context, config, 0, "%s -- %s", e_text, client_name);
	    e_text = NULL;
	    goto out;
	}
    }else if (config->require_preauth
	      || b->kdc_options.request_anonymous /* hack to force anon */
	      || client->entry.flags.require_preauth
	      || server->entry.flags.require_preauth) {
	METHOD_DATA method_data;
	PA_DATA *pa;
	unsigned char *buf;
	size_t len;

    use_pa:
	method_data.len = 0;
	method_data.val = NULL;

	ret = realloc_method_data(&method_data);
	if (ret) {
	    free_METHOD_DATA(&method_data);
	    goto out;
	}
	pa = &method_data.val[method_data.len-1];
	pa->padata_type		= KRB5_PADATA_ENC_TIMESTAMP;
	pa->padata_value.length	= 0;
	pa->padata_value.data	= NULL;

#ifdef PKINIT
	ret = realloc_method_data(&method_data);
	if (ret) {
	    free_METHOD_DATA(&method_data);
	    goto out;
	}
	pa = &method_data.val[method_data.len-1];
	pa->padata_type		= KRB5_PADATA_PK_AS_REQ;
	pa->padata_value.length	= 0;
	pa->padata_value.data	= NULL;

	ret = realloc_method_data(&method_data);
	if (ret) {
	    free_METHOD_DATA(&method_data);
	    goto out;
	}
	pa = &method_data.val[method_data.len-1];
	pa->padata_type		= KRB5_PADATA_PK_AS_REQ_WIN;
	pa->padata_value.length	= 0;
	pa->padata_value.data	= NULL;
#endif

	/*
	 * If there is a client key, send ETYPE_INFO{,2}
	 */
	ret = _kdc_find_etype(context,
			      config->preauth_use_strongest_session_key, TRUE,
			      client, b->etype.val, b->etype.len, NULL, &ckey);
	if (ret == 0) {

	    /*
	     * RFC4120 requires:
	     * - If the client only knows about old enctypes, then send
	     *   both info replies (we send 'info' first in the list).
	     * - If the client is 'modern', because it knows about 'new'
	     *   enctype types, then only send the 'info2' reply.
	     *
	     * Before we send the full list of etype-info data, we pick
	     * the client key we would have used anyway below, just pick
	     * that instead.
	     */

	    if (older_enctype(ckey->key.keytype)) {
		ret = get_pa_etype_info(context, config,
					&method_data, ckey);
		if (ret) {
		    free_METHOD_DATA(&method_data);
		    goto out;
		}
	    }
	    ret = get_pa_etype_info2(context, config,
				     &method_data, ckey);
	    if (ret) {
		free_METHOD_DATA(&method_data);
		goto out;
	    }
	}

	ASN1_MALLOC_ENCODE(METHOD_DATA, buf, len, &method_data, &len, ret);
	free_METHOD_DATA(&method_data);

	e_data.data   = buf;
	e_data.length = len;
	e_text ="Need to use PA-ENC-TIMESTAMP/PA-PK-AS-REQ",

	ret = KRB5KDC_ERR_PREAUTH_REQUIRED;

	kdc_log(context, config, 0,
		"No preauth found, returning PREAUTH-REQUIRED -- %s",
		client_name);
	goto out;
    }

    /*
     * Verify flags after the user been required to prove its identity
     * with in a preauth mech.
     */

    ret = _kdc_check_access(context, config, client, client_name,
			    server, server_name,
			    req, &e_data);
    if(ret)
	goto out;

    if (clientdb->hdb_auth_status)
	(clientdb->hdb_auth_status)(context, clientdb, client,
				    HDB_AUTH_SUCCESS);

    /*
     * Selelct the best encryption type for the KDC with out regard to
     * the client since the client never needs to read that data.
     */

    ret = _kdc_get_preferred_key(context, config,
				 server, server_name,
				 &setype, &skey);
    if(ret)
	goto out;

    if(f.renew || f.validate || f.proxy || f.forwarded || f.enc_tkt_in_skey
       || (f.request_anonymous && !config->allow_anonymous)) {
	ret = KRB5KDC_ERR_BADOPTION;
	e_text = "Bad KDC options";
	kdc_log(context, config, 0, "Bad KDC options -- %s", client_name);
	goto out;
    }

    rep.pvno = 5;
    rep.msg_type = krb_as_rep;

    ret = copy_Realm(&client->entry.principal->realm, &rep.crealm);
    if (ret)
	goto out;
    ret = _krb5_principal2principalname(&rep.cname, client->entry.principal);
    if (ret)
	goto out;

    rep.ticket.tkt_vno = 5;
    copy_Realm(&server->entry.principal->realm, &rep.ticket.realm);
    _krb5_principal2principalname(&rep.ticket.sname,
				  server->entry.principal);
    /* java 1.6 expects the name to be the same type, lets allow that
     * uncomplicated name-types. */
#define CNT(sp,t) (((sp)->sname->name_type) == KRB5_NT_##t)
    if (CNT(b, UNKNOWN) || CNT(b, PRINCIPAL) || CNT(b, SRV_INST) || CNT(b, SRV_HST) || CNT(b, SRV_XHST))
	rep.ticket.sname.name_type = b->sname->name_type;
#undef CNT

    et.flags.initial = 1;
    if(client->entry.flags.forwardable && server->entry.flags.forwardable)
	et.flags.forwardable = f.forwardable;
    else if (f.forwardable) {
	e_text = "Ticket may not be forwardable";
	ret = KRB5KDC_ERR_POLICY;
	kdc_log(context, config, 0,
		"Ticket may not be forwardable -- %s", client_name);
	goto out;
    }
    if(client->entry.flags.proxiable && server->entry.flags.proxiable)
	et.flags.proxiable = f.proxiable;
    else if (f.proxiable) {
	e_text = "Ticket may not be proxiable";
	ret = KRB5KDC_ERR_POLICY;
	kdc_log(context, config, 0,
		"Ticket may not be proxiable -- %s", client_name);
	goto out;
    }
    if(client->entry.flags.postdate && server->entry.flags.postdate)
	et.flags.may_postdate = f.allow_postdate;
    else if (f.allow_postdate){
	e_text = "Ticket may not be postdate";
	ret = KRB5KDC_ERR_POLICY;
	kdc_log(context, config, 0,
		"Ticket may not be postdatable -- %s", client_name);
	goto out;
    }

    /* check for valid set of addresses */
    if(!_kdc_check_addresses(context, config, b->addresses, from_addr)) {
	e_text = "Bad address list in requested";
	ret = KRB5KRB_AP_ERR_BADADDR;
	kdc_log(context, config, 0,
		"Bad address list requested -- %s", client_name);
	goto out;
    }

    ret = copy_PrincipalName(&rep.cname, &et.cname);
    if (ret)
	goto out;
    ret = copy_Realm(&rep.crealm, &et.crealm);
    if (ret)
	goto out;

    {
	time_t start;
	time_t t;

	start = et.authtime = kdc_time;

	if(f.postdated && req->req_body.from){
	    ALLOC(et.starttime);
	    start = *et.starttime = *req->req_body.from;
	    et.flags.invalid = 1;
	    et.flags.postdated = 1; /* XXX ??? */
	}
	_kdc_fix_time(&b->till);
	t = *b->till;

	/* be careful not overflowing */

	if(client->entry.max_life)
	    t = start + min(t - start, *client->entry.max_life);
	if(server->entry.max_life)
	    t = start + min(t - start, *server->entry.max_life);
#if 0
	t = min(t, start + realm->max_life);
#endif
	et.endtime = t;
	if(f.renewable_ok && et.endtime < *b->till){
	    f.renewable = 1;
	    if(b->rtime == NULL){
		ALLOC(b->rtime);
		*b->rtime = 0;
	    }
	    if(*b->rtime < *b->till)
		*b->rtime = *b->till;
	}
	if(f.renewable && b->rtime){
	    t = *b->rtime;
	    if(t == 0)
		t = MAX_TIME;
	    if(client->entry.max_renew)
		t = start + min(t - start, *client->entry.max_renew);
	    if(server->entry.max_renew)
		t = start + min(t - start, *server->entry.max_renew);
#if 0
	    t = min(t, start + realm->max_renew);
#endif
	    ALLOC(et.renew_till);
	    *et.renew_till = t;
	    et.flags.renewable = 1;
	}
    }

    if (f.request_anonymous)
	et.flags.anonymous = 1;

    if(b->addresses){
	ALLOC(et.caddr);
	copy_HostAddresses(b->addresses, et.caddr);
    }

    et.transited.tr_type = DOMAIN_X500_COMPRESS;
    krb5_data_zero(&et.transited.contents);

    /* The MIT ASN.1 library (obviously) doesn't tell lengths encoded
     * as 0 and as 0x80 (meaning indefinite length) apart, and is thus
     * incapable of correctly decoding SEQUENCE OF's of zero length.
     *
     * To fix this, always send at least one no-op last_req
     *
     * If there's a pw_end or valid_end we will use that,
     * otherwise just a dummy lr.
     */
    ek.last_req.val = malloc(2 * sizeof(*ek.last_req.val));
    if (ek.last_req.val == NULL) {
	ret = ENOMEM;
	goto out;
    }
    ek.last_req.len = 0;
    if (client->entry.pw_end
	&& (config->kdc_warn_pwexpire == 0
	    || kdc_time + config->kdc_warn_pwexpire >= *client->entry.pw_end)) {
	ek.last_req.val[ek.last_req.len].lr_type  = LR_PW_EXPTIME;
	ek.last_req.val[ek.last_req.len].lr_value = *client->entry.pw_end;
	++ek.last_req.len;
    }
    if (client->entry.valid_end) {
	ek.last_req.val[ek.last_req.len].lr_type  = LR_ACCT_EXPTIME;
	ek.last_req.val[ek.last_req.len].lr_value = *client->entry.valid_end;
	++ek.last_req.len;
    }
    if (ek.last_req.len == 0) {
	ek.last_req.val[ek.last_req.len].lr_type  = LR_NONE;
	ek.last_req.val[ek.last_req.len].lr_value = 0;
	++ek.last_req.len;
    }
    ek.nonce = b->nonce;
    if (client->entry.valid_end || client->entry.pw_end) {
	ALLOC(ek.key_expiration);
	if (client->entry.valid_end) {
	    if (client->entry.pw_end)
		*ek.key_expiration = min(*client->entry.valid_end,
					 *client->entry.pw_end);
	    else
		*ek.key_expiration = *client->entry.valid_end;
	} else
	    *ek.key_expiration = *client->entry.pw_end;
    } else
	ek.key_expiration = NULL;
    ek.flags = et.flags;
    ek.authtime = et.authtime;
    if (et.starttime) {
	ALLOC(ek.starttime);
	*ek.starttime = *et.starttime;
    }
    ek.endtime = et.endtime;
    if (et.renew_till) {
	ALLOC(ek.renew_till);
	*ek.renew_till = *et.renew_till;
    }
    copy_Realm(&rep.ticket.realm, &ek.srealm);
    copy_PrincipalName(&rep.ticket.sname, &ek.sname);
    if(et.caddr){
	ALLOC(ek.caddr);
	copy_HostAddresses(et.caddr, ek.caddr);
    }

#if PKINIT
    if (pkp) {
        e_text = "Failed to build PK-INIT reply";
	ret = _kdc_pk_mk_pa_reply(context, config, pkp, client,
				  sessionetype, req, req_buffer,
				  &reply_key, &et.key, rep.padata);
	if (ret)
	    goto out;
	ret = _kdc_add_inital_verified_cas(context,
					   config,
					   pkp,
					   &et);
	if (ret)
	    goto out;

    } else
#endif
    {
	ret = krb5_generate_random_keyblock(context, sessionetype, &et.key);
	if (ret)
	    goto out;
    }

    if (reply_key == NULL) {
	e_text = "Client have no reply key";
	ret = KRB5KDC_ERR_CLIENT_NOTYET;
	goto out;
    }

    ret = copy_EncryptionKey(&et.key, &ek.key);
    if (ret)
	goto out;

    if (rep.padata->len == 0) {
	free(rep.padata);
	rep.padata = NULL;
    }

    /* Add the PAC */
    if (send_pac_p(context, req)) {
	krb5_pac p = NULL;
	krb5_data data;

	ret = _kdc_pac_generate(context, client, &p);
	if (ret) {
	    kdc_log(context, config, 0, "PAC generation failed for -- %s",
		    client_name);
	    goto out;
	}
	if (p != NULL) {
	    ret = _krb5_pac_sign(context, p, et.authtime,
				 client->entry.principal,
				 &skey->key, /* Server key */
				 &skey->key, /* FIXME: should be krbtgt key */
				 &data);
	    krb5_pac_free(context, p);
	    if (ret) {
		kdc_log(context, config, 0, "PAC signing failed for -- %s",
			client_name);
		goto out;
	    }

	    ret = _kdc_tkt_add_if_relevant_ad(context, &et,
					      KRB5_AUTHDATA_WIN2K_PAC,
					      &data);
	    krb5_data_free(&data);
	    if (ret)
		goto out;
	}
    }

    _kdc_log_timestamp(context, config, "AS-REQ", et.authtime, et.starttime,
		       et.endtime, et.renew_till);

    /* do this as the last thing since this signs the EncTicketPart */
    ret = _kdc_add_KRB5SignedPath(context,
				  config,
				  server,
				  setype,
				  client->entry.principal,
				  NULL,
				  NULL,
				  &et);
    if (ret)
	goto out;

    log_as_req(context, config, reply_key->keytype, setype, b);

    ret = _kdc_encode_reply(context, config,
			    &rep, &et, &ek, setype, server->entry.kvno,
			    &skey->key, client->entry.kvno,
			    reply_key, 0, &e_text, reply);
    free_EncTicketPart(&et);
    free_EncKDCRepPart(&ek);
    if (ret)
	goto out;

    /* */
    if (datagram_reply && reply->length > config->max_datagram_reply_length) {
	krb5_data_free(reply);
	ret = KRB5KRB_ERR_RESPONSE_TOO_BIG;
	e_text = "Reply packet too large";
    }

out:
    free_AS_REP(&rep);
    if(ret != 0 && ret != HDB_ERR_NOT_FOUND_HERE){
	krb5_mk_error(context,
		      ret,
		      e_text,
		      (e_data.data ? &e_data : NULL),
		      client_princ,
		      server_princ,
		      NULL,
		      NULL,
		      reply);
	ret = 0;
    }
#ifdef PKINIT
    if (pkp)
	_kdc_pk_free_client_param(context, pkp);
#endif
    if (e_data.data)
        free(e_data.data);
    if (client_princ)
	krb5_free_principal(context, client_princ);
    free(client_name);
    if (server_princ)
	krb5_free_principal(context, server_princ);
    free(server_name);
    if(client)
	_kdc_free_ent(context, client);
    if(server)
	_kdc_free_ent(context, server);
    return ret;
}
コード例 #2
0
ファイル: kerberos5.c プロジェクト: 2014-class/freerouter
krb5_error_code
_kdc_as_rep(krb5_context context, 
	    krb5_kdc_configuration *config,
	    KDC_REQ *req, 
	    const krb5_data *req_buffer, 
	    krb5_data *reply,
	    const char *from,
	    struct sockaddr *from_addr,
	    int datagram_reply)
{
    KDC_REQ_BODY *b = &req->req_body;
    AS_REP rep;
    KDCOptions f = b->kdc_options;
    hdb_entry_ex *client = NULL, *server = NULL;
    krb5_enctype cetype, setype, sessionetype;
    krb5_data e_data;
    EncTicketPart et;
    EncKDCRepPart ek;
    krb5_principal client_princ = NULL, server_princ = NULL;
    char *client_name = NULL, *server_name = NULL;
    krb5_error_code ret = 0;
    const char *e_text = NULL;
    krb5_crypto crypto;
    Key *ckey, *skey;
    EncryptionKey *reply_key;
    int flags = 0;
#ifdef PKINIT
    pk_client_params *pkp = NULL;
#endif

    memset(&rep, 0, sizeof(rep));
    krb5_data_zero(&e_data);

    if (f.canonicalize)
	flags |= HDB_F_CANON;

    if(b->sname == NULL){
	ret = KRB5KRB_ERR_GENERIC;
	e_text = "No server in request";
    } else{
	ret = _krb5_principalname2krb5_principal (context,
						  &server_princ,
						  *(b->sname),
						  b->realm);
	if (ret == 0)
	    ret = krb5_unparse_name(context, server_princ, &server_name);
    }
    if (ret) {
	kdc_log(context, config, 0, 
		"AS-REQ malformed server name from %s", from);
	goto out;
    }
    
    if(b->cname == NULL){
	ret = KRB5KRB_ERR_GENERIC;
	e_text = "No client in request";
    } else {

	if (b->cname->name_type == KRB5_NT_ENTERPRISE_PRINCIPAL) {
	    if (b->cname->name_string.len != 1) {
		kdc_log(context, config, 0,
			"AS-REQ malformed canon request from %s, "
			"enterprise name with %d name components", 
			from, b->cname->name_string.len);
		ret = KRB5_PARSE_MALFORMED;
		goto out;
	    }
	    ret = krb5_parse_name(context, b->cname->name_string.val[0],
				  &client_princ);
	    if (ret)
		goto out;
	} else {
	    ret = _krb5_principalname2krb5_principal (context,
						      &client_princ,
						      *(b->cname),
						      b->realm);
	    if (ret)
		goto out;
	}
	ret = krb5_unparse_name(context, client_princ, &client_name);
    }
    if (ret) {
	kdc_log(context, config, 0,
		"AS-REQ malformed client name from %s", from);
	goto out;
    }

    kdc_log(context, config, 0, "AS-REQ %s from %s for %s", 
	    client_name, from, server_name);

    ret = _kdc_db_fetch(context, config, client_princ, 
			HDB_F_GET_CLIENT | flags, NULL, &client);
    if(ret){
	kdc_log(context, config, 0, "UNKNOWN -- %s: %s", client_name,
		krb5_get_err_text(context, ret));
	ret = KRB5KDC_ERR_C_PRINCIPAL_UNKNOWN;
	goto out;
    }

    ret = _kdc_db_fetch(context, config, server_princ,
			HDB_F_GET_SERVER|HDB_F_GET_KRBTGT,
			NULL, &server);
    if(ret){
	kdc_log(context, config, 0, "UNKNOWN -- %s: %s", server_name,
		krb5_get_err_text(context, ret));
	ret = KRB5KDC_ERR_S_PRINCIPAL_UNKNOWN;
	goto out;
    }

    ret = _kdc_windc_client_access(context, client, req);
    if(ret)
	goto out;

    ret = _kdc_check_flags(context, config, 
			   client, client_name,
			   server, server_name,
			   TRUE);
    if(ret)
	goto out;

    memset(&et, 0, sizeof(et));
    memset(&ek, 0, sizeof(ek));

    if(req->padata){
	int i;
	const PA_DATA *pa;
	int found_pa = 0;

	log_patypes(context, config, req->padata);

#ifdef PKINIT
	kdc_log(context, config, 5, 
		"Looking for PKINIT pa-data -- %s", client_name);

	e_text = "No PKINIT PA found";

	i = 0;
	if ((pa = _kdc_find_padata(req, &i, KRB5_PADATA_PK_AS_REQ)))
	    ;
	if (pa == NULL) {
	    i = 0;
	    if((pa = _kdc_find_padata(req, &i, KRB5_PADATA_PK_AS_REQ_WIN)))
		;
	}
	if (pa) {
	    char *client_cert = NULL;

	    ret = _kdc_pk_rd_padata(context, config, req, pa, &pkp);
	    if (ret) {
		ret = KRB5KRB_AP_ERR_BAD_INTEGRITY;
		kdc_log(context, config, 5, 
			"Failed to decode PKINIT PA-DATA -- %s", 
			client_name);
		goto ts_enc;
	    }
	    if (ret == 0 && pkp == NULL)
		goto ts_enc;

	    ret = _kdc_pk_check_client(context,
				       config,
				       client,
				       pkp,
				       &client_cert);
	    if (ret) {
		e_text = "PKINIT certificate not allowed to "
		    "impersonate principal";
		_kdc_pk_free_client_param(context, pkp);

		kdc_log(context, config, 0, "%s", e_text);
		pkp = NULL;
		goto out;
	    }
	    found_pa = 1;
	    et.flags.pre_authent = 1;
	    kdc_log(context, config, 0,
		    "PKINIT pre-authentication succeeded -- %s using %s", 
		    client_name, client_cert);
	    free(client_cert);
	    if (pkp)
		goto preauth_done;
	}
    ts_enc:
#endif
	kdc_log(context, config, 5, "Looking for ENC-TS pa-data -- %s", 
		client_name);

	i = 0;
	e_text = "No ENC-TS found";
	while((pa = _kdc_find_padata(req, &i, KRB5_PADATA_ENC_TIMESTAMP))){
	    krb5_data ts_data;
	    PA_ENC_TS_ENC p;
	    size_t len;
	    EncryptedData enc_data;
	    Key *pa_key;
	    char *str;
	    
	    found_pa = 1;
	    
	    ret = decode_EncryptedData(pa->padata_value.data,
				       pa->padata_value.length,
				       &enc_data,
				       &len);
	    if (ret) {
		ret = KRB5KRB_AP_ERR_BAD_INTEGRITY;
		kdc_log(context, config, 5, "Failed to decode PA-DATA -- %s", 
			client_name);
		goto out;
	    }
	    
	    ret = hdb_enctype2key(context, &client->entry, 
				  enc_data.etype, &pa_key);
	    if(ret){
		char *estr;
		e_text = "No key matches pa-data";
		ret = KRB5KDC_ERR_ETYPE_NOSUPP;
		if(krb5_enctype_to_string(context, enc_data.etype, &estr))
		    estr = NULL;
		if(estr == NULL)
		    kdc_log(context, config, 5, 
			    "No client key matching pa-data (%d) -- %s", 
			    enc_data.etype, client_name);
		else
		    kdc_log(context, config, 5,
			    "No client key matching pa-data (%s) -- %s", 
			    estr, client_name);
		free(estr);
		    
		free_EncryptedData(&enc_data);
		continue;
	    }

	try_next_key:
	    ret = krb5_crypto_init(context, &pa_key->key, 0, &crypto);
	    if (ret) {
		kdc_log(context, config, 0, "krb5_crypto_init failed: %s",
			krb5_get_err_text(context, ret));
		free_EncryptedData(&enc_data);
		continue;
	    }

	    ret = krb5_decrypt_EncryptedData (context,
					      crypto,
					      KRB5_KU_PA_ENC_TIMESTAMP,
					      &enc_data,
					      &ts_data);
	    krb5_crypto_destroy(context, crypto);
	    if(ret){
		krb5_error_code ret2;
		ret2 = krb5_enctype_to_string(context, 
					      pa_key->key.keytype, &str);
		if (ret2)
		    str = NULL;
		kdc_log(context, config, 5, 
			"Failed to decrypt PA-DATA -- %s "
			"(enctype %s) error %s",
			client_name,
			str ? str : "unknown enctype", 
			krb5_get_err_text(context, ret));
		free(str);

		if(hdb_next_enctype2key(context, &client->entry, 
					enc_data.etype, &pa_key) == 0)
		    goto try_next_key;
		e_text = "Failed to decrypt PA-DATA";

		free_EncryptedData(&enc_data);
		ret = KRB5KDC_ERR_PREAUTH_FAILED;
		continue;
	    }
	    free_EncryptedData(&enc_data);
	    ret = decode_PA_ENC_TS_ENC(ts_data.data,
				       ts_data.length,
				       &p,
				       &len);
	    krb5_data_free(&ts_data);
	    if(ret){
		e_text = "Failed to decode PA-ENC-TS-ENC";
		ret = KRB5KDC_ERR_PREAUTH_FAILED;
		kdc_log(context, config, 
			5, "Failed to decode PA-ENC-TS_ENC -- %s",
			client_name);
		continue;
	    }
	    free_PA_ENC_TS_ENC(&p);
	    if (abs(kdc_time - p.patimestamp) > context->max_skew) {
		char client_time[100];
		
		krb5_format_time(context, p.patimestamp, 
				 client_time, sizeof(client_time), TRUE); 

 		ret = KRB5KRB_AP_ERR_SKEW;
 		kdc_log(context, config, 0,
			"Too large time skew, "
			"client time %s is out by %u > %u seconds -- %s", 
			client_time, 
			(unsigned)abs(kdc_time - p.patimestamp), 
			context->max_skew,
			client_name);
#if 0
		/* This code is from samba, needs testing */
		/* 
		 * the following is needed to make windows clients
		 * to retry using the timestamp in the error message
		 *
		 * this is maybe a bug in windows to not trying when e_text
		 * is present...
		 */
		e_text = NULL;
#else
		e_text = "Too large time skew";
#endif
		goto out;
	    }
	    et.flags.pre_authent = 1;

	    ret = krb5_enctype_to_string(context,pa_key->key.keytype, &str);
	    if (ret)
		str = NULL;

	    kdc_log(context, config, 2,
		    "ENC-TS Pre-authentication succeeded -- %s using %s", 
		    client_name, str ? str : "unknown enctype");
	    free(str);
	    break;
	}
#ifdef PKINIT
    preauth_done:
#endif
	if(found_pa == 0 && config->require_preauth)
	    goto use_pa;
	/* We come here if we found a pa-enc-timestamp, but if there
           was some problem with it, other than too large skew */
	if(found_pa && et.flags.pre_authent == 0){
	    kdc_log(context, config, 0, "%s -- %s", e_text, client_name);
	    e_text = NULL;
	    goto out;
	}
    }else if (config->require_preauth
	      || client->entry.flags.require_preauth
	      || server->entry.flags.require_preauth) {
	METHOD_DATA method_data;
	PA_DATA *pa;
	unsigned char *buf;
	size_t len;

    use_pa: 
	method_data.len = 0;
	method_data.val = NULL;

	ret = realloc_method_data(&method_data);
	pa = &method_data.val[method_data.len-1];
	pa->padata_type		= KRB5_PADATA_ENC_TIMESTAMP;
	pa->padata_value.length	= 0;
	pa->padata_value.data	= NULL;

#ifdef PKINIT
	ret = realloc_method_data(&method_data);
	pa = &method_data.val[method_data.len-1];
	pa->padata_type		= KRB5_PADATA_PK_AS_REQ;
	pa->padata_value.length	= 0;
	pa->padata_value.data	= NULL;

	ret = realloc_method_data(&method_data);
	pa = &method_data.val[method_data.len-1];
	pa->padata_type		= KRB5_PADATA_PK_AS_REQ_WIN;
	pa->padata_value.length	= 0;
	pa->padata_value.data	= NULL;
#endif

	/* 
	 * RFC4120 requires: 
	 * - If the client only knows about old enctypes, then send
	 *   both info replies (we send 'info' first in the list).
	 * - If the client is 'modern', because it knows about 'new'
	 *   enctype types, then only send the 'info2' reply.
	 */

	/* XXX check ret */
	if (only_older_enctype_p(req))
	    ret = get_pa_etype_info(context, config,
				    &method_data, &client->entry, 
				    b->etype.val, b->etype.len); 
	/* XXX check ret */
	ret = get_pa_etype_info2(context, config, &method_data, 
				 &client->entry, b->etype.val, b->etype.len);

	
	ASN1_MALLOC_ENCODE(METHOD_DATA, buf, len, &method_data, &len, ret);
	free_METHOD_DATA(&method_data);

	e_data.data   = buf;
	e_data.length = len;
	e_text ="Need to use PA-ENC-TIMESTAMP/PA-PK-AS-REQ",

	ret = KRB5KDC_ERR_PREAUTH_REQUIRED;

	kdc_log(context, config, 0,
		"No preauth found, returning PREAUTH-REQUIRED -- %s",
		client_name);
	goto out;
    }
    
    /*
     * Find the client key (for preauth ENC-TS verification and reply
     * encryption).  Then the best encryption type for the KDC and
     * last the best session key that shared between the client and
     * KDC runtime enctypes.
     */

    ret = _kdc_find_etype(context, client, b->etype.val, b->etype.len,
			  &ckey, &cetype);
    if (ret) {
	kdc_log(context, config, 0, 
		"Client (%s) has no support for etypes", client_name);
	goto out;
    }
	
    ret = _kdc_get_preferred_key(context, config,
				 server, server_name,
				 &setype, &skey);
    if(ret)
	goto out;

    /* 
     * Select a session enctype from the list of the crypto systems
     * supported enctype, is supported by the client and is one of the
     * enctype of the enctype of the krbtgt.
     *
     * The later is used as a hint what enctype all KDC are supporting
     * to make sure a newer version of KDC wont generate a session
     * enctype that and older version of a KDC in the same realm can't
     * decrypt.
     *
     * But if the KDC admin is paranoid and doesn't want to have "no
     * the best" enctypes on the krbtgt, lets save the best pick from
     * the client list and hope that that will work for any other
     * KDCs.
     */
    {
	const krb5_enctype *p;
	krb5_enctype clientbest = ETYPE_NULL;
	int i, j;

	p = krb5_kerberos_enctypes(context);

	sessionetype = ETYPE_NULL;

	for (i = 0; p[i] != ETYPE_NULL && sessionetype == ETYPE_NULL; i++) {
	    if (krb5_enctype_valid(context, p[i]) != 0)
		continue;

	    for (j = 0; j < b->etype.len && sessionetype == ETYPE_NULL; j++) {
		Key *dummy;
		/* check with client */
		if (p[i] != b->etype.val[j])
		    continue; 
		/* save best of union of { client, crypto system } */
		if (clientbest == ETYPE_NULL)
		    clientbest = p[i];
		/* check with krbtgt */
		ret = hdb_enctype2key(context, &server->entry, p[i], &dummy);
		if (ret) 
		    continue;
		sessionetype = p[i];
	    }
	}
	/* if krbtgt had no shared keys with client, pick clients best */
	if (clientbest != ETYPE_NULL && sessionetype == ETYPE_NULL) {
	    sessionetype = clientbest;
	} else if (sessionetype == ETYPE_NULL) {
	    kdc_log(context, config, 0,
		    "Client (%s) from %s has no common enctypes with KDC"
		    "to use for the session key", 
		    client_name, from); 
	    goto out;
	}
    }

    log_as_req(context, config, cetype, setype, b);

    if(f.renew || f.validate || f.proxy || f.forwarded || f.enc_tkt_in_skey
       || (f.request_anonymous && !config->allow_anonymous)) {
	ret = KRB5KDC_ERR_BADOPTION;
	kdc_log(context, config, 0, "Bad KDC options -- %s", client_name);
	goto out;
    }
    
    rep.pvno = 5;
    rep.msg_type = krb_as_rep;
    copy_Realm(&client->entry.principal->realm, &rep.crealm);
    if (f.request_anonymous)
	_kdc_make_anonymous_principalname (&rep.cname);
    else
	_krb5_principal2principalname(&rep.cname, 
				      client->entry.principal);
    rep.ticket.tkt_vno = 5;
    copy_Realm(&server->entry.principal->realm, &rep.ticket.realm);
    _krb5_principal2principalname(&rep.ticket.sname, 
				  server->entry.principal);
    /* java 1.6 expects the name to be the same type, lets allow that
     * uncomplicated name-types. */
#define CNT(sp,t) (((sp)->sname->name_type) == KRB5_NT_##t)
    if (CNT(b, UNKNOWN) || CNT(b, PRINCIPAL) || CNT(b, SRV_INST) || CNT(b, SRV_HST) || CNT(b, SRV_XHST))
	rep.ticket.sname.name_type = b->sname->name_type;
#undef CNT

    et.flags.initial = 1;
    if(client->entry.flags.forwardable && server->entry.flags.forwardable)
	et.flags.forwardable = f.forwardable;
    else if (f.forwardable) {
	ret = KRB5KDC_ERR_POLICY;
	kdc_log(context, config, 0,
		"Ticket may not be forwardable -- %s", client_name);
	goto out;
    }
    if(client->entry.flags.proxiable && server->entry.flags.proxiable)
	et.flags.proxiable = f.proxiable;
    else if (f.proxiable) {
	ret = KRB5KDC_ERR_POLICY;
	kdc_log(context, config, 0, 
		"Ticket may not be proxiable -- %s", client_name);
	goto out;
    }
    if(client->entry.flags.postdate && server->entry.flags.postdate)
	et.flags.may_postdate = f.allow_postdate;
    else if (f.allow_postdate){
	ret = KRB5KDC_ERR_POLICY;
	kdc_log(context, config, 0,
		"Ticket may not be postdatable -- %s", client_name);
	goto out;
    }

    /* check for valid set of addresses */
    if(!_kdc_check_addresses(context, config, b->addresses, from_addr)) {
	ret = KRB5KRB_AP_ERR_BADADDR;
	kdc_log(context, config, 0,
		"Bad address list requested -- %s", client_name);
	goto out;
    }

    ret = krb5_generate_random_keyblock(context, sessionetype, &et.key);
    if (ret)
	goto out;
    copy_PrincipalName(&rep.cname, &et.cname);
    copy_Realm(&rep.crealm, &et.crealm);
    
    {
	time_t start;
	time_t t;
	
	start = et.authtime = kdc_time;
    
	if(f.postdated && req->req_body.from){
	    ALLOC(et.starttime);
	    start = *et.starttime = *req->req_body.from;
	    et.flags.invalid = 1;
	    et.flags.postdated = 1; /* XXX ??? */
	}
	_kdc_fix_time(&b->till);
	t = *b->till;

	/* be careful not overflowing */

	if(client->entry.max_life)
	    t = start + min(t - start, *client->entry.max_life);
	if(server->entry.max_life)
	    t = start + min(t - start, *server->entry.max_life);
#if 0
	t = min(t, start + realm->max_life);
#endif
	et.endtime = t;
	if(f.renewable_ok && et.endtime < *b->till){
	    f.renewable = 1;
	    if(b->rtime == NULL){
		ALLOC(b->rtime);
		*b->rtime = 0;
	    }
	    if(*b->rtime < *b->till)
		*b->rtime = *b->till;
	}
	if(f.renewable && b->rtime){
	    t = *b->rtime;
	    if(t == 0)
		t = MAX_TIME;
	    if(client->entry.max_renew)
		t = start + min(t - start, *client->entry.max_renew);
	    if(server->entry.max_renew)
		t = start + min(t - start, *server->entry.max_renew);
#if 0
	    t = min(t, start + realm->max_renew);
#endif
	    ALLOC(et.renew_till);
	    *et.renew_till = t;
	    et.flags.renewable = 1;
	}
    }

    if (f.request_anonymous)
	et.flags.anonymous = 1;
    
    if(b->addresses){
	ALLOC(et.caddr);
	copy_HostAddresses(b->addresses, et.caddr);
    }
    
    et.transited.tr_type = DOMAIN_X500_COMPRESS;
    krb5_data_zero(&et.transited.contents); 
     
    copy_EncryptionKey(&et.key, &ek.key);

    /* The MIT ASN.1 library (obviously) doesn't tell lengths encoded
     * as 0 and as 0x80 (meaning indefinite length) apart, and is thus
     * incapable of correctly decoding SEQUENCE OF's of zero length.
     *
     * To fix this, always send at least one no-op last_req
     *
     * If there's a pw_end or valid_end we will use that,
     * otherwise just a dummy lr.
     */
    ek.last_req.val = malloc(2 * sizeof(*ek.last_req.val));
    if (ek.last_req.val == NULL) {
	ret = ENOMEM;
	goto out;
    }
    ek.last_req.len = 0;
    if (client->entry.pw_end
	&& (config->kdc_warn_pwexpire == 0
	    || kdc_time + config->kdc_warn_pwexpire >= *client->entry.pw_end)) {
	ek.last_req.val[ek.last_req.len].lr_type  = LR_PW_EXPTIME;
	ek.last_req.val[ek.last_req.len].lr_value = *client->entry.pw_end;
	++ek.last_req.len;
    }
    if (client->entry.valid_end) {
	ek.last_req.val[ek.last_req.len].lr_type  = LR_ACCT_EXPTIME;
	ek.last_req.val[ek.last_req.len].lr_value = *client->entry.valid_end;
	++ek.last_req.len;
    }
    if (ek.last_req.len == 0) {
	ek.last_req.val[ek.last_req.len].lr_type  = LR_NONE;
	ek.last_req.val[ek.last_req.len].lr_value = 0;
	++ek.last_req.len;
    }
    ek.nonce = b->nonce;
    if (client->entry.valid_end || client->entry.pw_end) {
	ALLOC(ek.key_expiration);
	if (client->entry.valid_end) {
	    if (client->entry.pw_end)
		*ek.key_expiration = min(*client->entry.valid_end, 
					 *client->entry.pw_end);
	    else
		*ek.key_expiration = *client->entry.valid_end;
	} else
	    *ek.key_expiration = *client->entry.pw_end;
    } else
	ek.key_expiration = NULL;
    ek.flags = et.flags;
    ek.authtime = et.authtime;
    if (et.starttime) {
	ALLOC(ek.starttime);
	*ek.starttime = *et.starttime;
    }
    ek.endtime = et.endtime;
    if (et.renew_till) {
	ALLOC(ek.renew_till);
	*ek.renew_till = *et.renew_till;
    }
    copy_Realm(&rep.ticket.realm, &ek.srealm);
    copy_PrincipalName(&rep.ticket.sname, &ek.sname);
    if(et.caddr){
	ALLOC(ek.caddr);
	copy_HostAddresses(et.caddr, ek.caddr);
    }

    ALLOC(rep.padata);
    rep.padata->len = 0;
    rep.padata->val = NULL;

    reply_key = &ckey->key;
#if PKINIT
    if (pkp) {
	ret = _kdc_pk_mk_pa_reply(context, config, pkp, client, 
				  req, req_buffer, 
				  &reply_key, rep.padata);
	if (ret)
	    goto out;
	ret = _kdc_add_inital_verified_cas(context,
					   config,
					   pkp,
					   &et);
	if (ret)
	    goto out;
    }
#endif

    set_salt_padata (rep.padata, ckey->salt);

    /* Add signing of alias referral */
    if (f.canonicalize) {
	PA_ClientCanonicalized canon;
	krb5_data data;
	PA_DATA pa;
	krb5_crypto crypto;
	size_t len;

	memset(&canon, 0, sizeof(canon));

	canon.names.requested_name = *b->cname;
	canon.names.real_name = client->entry.principal->name;

	ASN1_MALLOC_ENCODE(PA_ClientCanonicalizedNames, data.data, data.length,
			   &canon.names, &len, ret);
	if (ret) 
	    goto out;
	if (data.length != len)
	    krb5_abortx(context, "internal asn.1 error");

	/* sign using "returned session key" */
	ret = krb5_crypto_init(context, &et.key, 0, &crypto);
	if (ret) {
	    free(data.data);
	    goto out;
	}

	ret = krb5_create_checksum(context, crypto, 
				   KRB5_KU_CANONICALIZED_NAMES, 0,
				   data.data, data.length,
				   &canon.canon_checksum);
	free(data.data);
	krb5_crypto_destroy(context, crypto);
	if (ret)
	    goto out;
	  
	ASN1_MALLOC_ENCODE(PA_ClientCanonicalized, data.data, data.length,
			   &canon, &len, ret);
	free_Checksum(&canon.canon_checksum);
	if (ret) 
	    goto out;
	if (data.length != len)
	    krb5_abortx(context, "internal asn.1 error");

	pa.padata_type = KRB5_PADATA_CLIENT_CANONICALIZED;
	pa.padata_value = data;
	ret = add_METHOD_DATA(rep.padata, &pa);
	free(data.data);
	if (ret)
	    goto out;
    }

    if (rep.padata->len == 0) {
	free(rep.padata);
	rep.padata = NULL;
    }

    /* Add the PAC */
    if (send_pac_p(context, req)) {
	krb5_pac p = NULL;
	krb5_data data;

	ret = _kdc_pac_generate(context, client, &p);
	if (ret) {
	    kdc_log(context, config, 0, "PAC generation failed for -- %s", 
		    client_name);
	    goto out;
	}
	if (p != NULL) {
	    ret = _krb5_pac_sign(context, p, et.authtime,
				 client->entry.principal,
				 &skey->key, /* Server key */ 
				 &skey->key, /* FIXME: should be krbtgt key */
				 &data);
	    krb5_pac_free(context, p);
	    if (ret) {
		kdc_log(context, config, 0, "PAC signing failed for -- %s", 
			client_name);
		goto out;
	    }

	    ret = _kdc_tkt_add_if_relevant_ad(context, &et,
					      KRB5_AUTHDATA_WIN2K_PAC,
					      &data);
	    krb5_data_free(&data);
	    if (ret)
		goto out;
	}
    }

    _kdc_log_timestamp(context, config, "AS-REQ", et.authtime, et.starttime, 
		       et.endtime, et.renew_till);

    /* do this as the last thing since this signs the EncTicketPart */
    ret = _kdc_add_KRB5SignedPath(context,
				  config,
				  server,
				  setype,
				  NULL,
				  NULL,
				  &et);
    if (ret)
	goto out;

    ret = _kdc_encode_reply(context, config, 
			    &rep, &et, &ek, setype, server->entry.kvno, 
			    &skey->key, client->entry.kvno, 
			    reply_key, &e_text, reply);
    free_EncTicketPart(&et);
    free_EncKDCRepPart(&ek);
    if (ret)
	goto out;

    /* */
    if (datagram_reply && reply->length > config->max_datagram_reply_length) {
	krb5_data_free(reply);
	ret = KRB5KRB_ERR_RESPONSE_TOO_BIG;
	e_text = "Reply packet too large";
    }

out:
    free_AS_REP(&rep);
    if(ret){
	krb5_mk_error(context,
		      ret,
		      e_text,
		      (e_data.data ? &e_data : NULL),
		      client_princ,
		      server_princ,
		      NULL,
		      NULL,
		      reply);
	ret = 0;
    }
#ifdef PKINIT
    if (pkp)
	_kdc_pk_free_client_param(context, pkp);
#endif
    if (e_data.data)
        free(e_data.data);
    if (client_princ)
	krb5_free_principal(context, client_princ);
    free(client_name);
    if (server_princ)
	krb5_free_principal(context, server_princ);
    free(server_name);
    if(client)
	_kdc_free_ent(context, client);
    if(server)
	_kdc_free_ent(context, server);
    return ret;
}
コード例 #3
0
ファイル: do_as_req.c プロジェクト: detrout/debian-krb5
static void
finish_process_as_req(struct as_req_state *state, krb5_error_code errcode)
{
    krb5_key_data *server_key;
    krb5_key_data *client_key;
    krb5_keyblock *as_encrypting_key = NULL;
    krb5_data *response = NULL;
    const char *emsg = 0;
    int did_log = 0;
    register int i;
    krb5_enctype useenctype;
    loop_respond_fn oldrespond;
    void *oldarg;
    kdc_realm_t *kdc_active_realm = state->active_realm;

    assert(state);
    oldrespond = state->respond;
    oldarg = state->arg;

    if (errcode)
        goto egress;

    if ((errcode = validate_forwardable(state->request, *state->client,
                                        *state->server, state->kdc_time,
                                        &state->status))) {
        errcode += ERROR_TABLE_BASE_krb5;
        goto egress;
    }

    state->ticket_reply.enc_part2 = &state->enc_tkt_reply;

    /*
     * Find the server key
     */
    if ((errcode = krb5_dbe_find_enctype(kdc_context, state->server,
                                         -1, /* ignore keytype   */
                                         -1, /* Ignore salttype  */
                                         0,  /* Get highest kvno */
                                         &server_key))) {
        state->status = "FINDING_SERVER_KEY";
        goto egress;
    }

    /*
     * Convert server->key into a real key
     * (it may be encrypted in the database)
     *
     *  server_keyblock is later used to generate auth data signatures
     */
    if ((errcode = krb5_dbe_decrypt_key_data(kdc_context, NULL,
                                             server_key,
                                             &state->server_keyblock,
                                             NULL))) {
        state->status = "DECRYPT_SERVER_KEY";
        goto egress;
    }

    /*
     * Find the appropriate client key.  We search in the order specified
     * by request keytype list.
     */
    client_key = NULL;
    useenctype = 0;
    for (i = 0; i < state->request->nktypes; i++) {
        useenctype = state->request->ktype[i];
        if (!krb5_c_valid_enctype(useenctype))
            continue;

        if (!krb5_dbe_find_enctype(kdc_context, state->client,
                                   useenctype, -1, 0, &client_key))
            break;
    }
    if (!(client_key)) {
        /* Cannot find an appropriate key */
        state->status = "CANT_FIND_CLIENT_KEY";
        errcode = KRB5KDC_ERR_ETYPE_NOSUPP;
        goto egress;
    }
    state->rock.client_key = client_key;

    /* convert client.key_data into a real key */
    if ((errcode = krb5_dbe_decrypt_key_data(kdc_context, NULL,
                                             client_key,
                                             &state->client_keyblock,
                                             NULL))) {
        state->status = "DECRYPT_CLIENT_KEY";
        goto egress;
    }
    state->client_keyblock.enctype = useenctype;

    /* Start assembling the response */
    state->reply.msg_type = KRB5_AS_REP;
    state->reply.client = state->enc_tkt_reply.client; /* post canonization */
    state->reply.ticket = &state->ticket_reply;
    state->reply_encpart.session = &state->session_key;
    if ((errcode = fetch_last_req_info(state->client,
                                       &state->reply_encpart.last_req))) {
        state->status = "FETCH_LAST_REQ";
        goto egress;
    }
    state->reply_encpart.nonce = state->request->nonce;
    state->reply_encpart.key_exp = get_key_exp(state->client);
    state->reply_encpart.flags = state->enc_tkt_reply.flags;
    state->reply_encpart.server = state->ticket_reply.server;

    /* copy the time fields EXCEPT for authtime; it's location
     *  is used for ktime
     */
    state->reply_encpart.times = state->enc_tkt_reply.times;
    state->reply_encpart.times.authtime = state->authtime = state->kdc_time;

    state->reply_encpart.caddrs = state->enc_tkt_reply.caddrs;
    state->reply_encpart.enc_padata = NULL;

    /* Fetch the padata info to be returned (do this before
     *  authdata to handle possible replacement of reply key
     */
    errcode = return_padata(kdc_context, &state->rock, state->req_pkt,
                            state->request, &state->reply,
                            &state->client_keyblock, &state->pa_context);
    if (errcode) {
        state->status = "KDC_RETURN_PADATA";
        goto egress;
    }

    errcode = handle_authdata(kdc_context,
                              state->c_flags,
                              state->client,
                              state->server,
                              state->server,
                              &state->client_keyblock,
                              &state->server_keyblock,
                              &state->server_keyblock,
                              state->req_pkt,
                              state->request,
                              NULL, /* for_user_princ */
                              NULL, /* enc_tkt_request */
                              &state->enc_tkt_reply);
    if (errcode) {
        krb5_klog_syslog(LOG_INFO, _("AS_REQ : handle_authdata (%d)"),
                         errcode);
        state->status = "HANDLE_AUTHDATA";
        goto egress;
    }

    errcode = krb5_encrypt_tkt_part(kdc_context, &state->server_keyblock,
                                    &state->ticket_reply);
    if (errcode) {
        state->status = "ENCRYPTING_TICKET";
        goto egress;
    }
    state->ticket_reply.enc_part.kvno = server_key->key_data_kvno;
    errcode = kdc_fast_response_handle_padata(state->rstate,
                                              state->request,
                                              &state->reply,
                                              state->client_keyblock.enctype);
    if (errcode) {
        state->status = "fast response handling";
        goto egress;
    }

    /* now encode/encrypt the response */

    state->reply.enc_part.enctype = state->client_keyblock.enctype;

    errcode = kdc_fast_handle_reply_key(state->rstate, &state->client_keyblock,
                                        &as_encrypting_key);
    if (errcode) {
        state->status = "generating reply key";
        goto egress;
    }
    errcode = return_enc_padata(kdc_context, state->req_pkt, state->request,
                                as_encrypting_key, state->server,
                                &state->reply_encpart, FALSE);
    if (errcode) {
        state->status = "KDC_RETURN_ENC_PADATA";
        goto egress;
    }

    errcode = krb5_encode_kdc_rep(kdc_context, KRB5_AS_REP,
                                  &state->reply_encpart, 0,
                                  as_encrypting_key,
                                  &state->reply, &response);
    state->reply.enc_part.kvno = client_key->key_data_kvno;
    if (errcode) {
        state->status = "ENCODE_KDC_REP";
        goto egress;
    }

    /* these parts are left on as a courtesy from krb5_encode_kdc_rep so we
       can use them in raw form if needed.  But, we don't... */
    memset(state->reply.enc_part.ciphertext.data, 0,
           state->reply.enc_part.ciphertext.length);
    free(state->reply.enc_part.ciphertext.data);

    log_as_req(kdc_context, state->from, state->request, &state->reply,
               state->client, state->cname, state->server,
               state->sname, state->authtime, 0, 0, 0);
    did_log = 1;

egress:
    if (errcode != 0)
        assert (state->status != 0);
    free_padata_context(kdc_context, state->pa_context);
    if (as_encrypting_key)
        krb5_free_keyblock(kdc_context, as_encrypting_key);
    if (errcode)
        emsg = krb5_get_error_message(kdc_context, errcode);

    if (state->status) {
        log_as_req(kdc_context,
                   state->from, state->request, &state->reply, state->client,
                   state->cname, state->server, state->sname, state->authtime,
                   state->status, errcode, emsg);
        did_log = 1;
    }
    if (errcode) {
        if (state->status == 0) {
            state->status = emsg;
        }
        if (errcode != KRB5KDC_ERR_DISCARD) {
            errcode -= ERROR_TABLE_BASE_krb5;
            if (errcode < 0 || errcode > 128)
                errcode = KRB_ERR_GENERIC;

            errcode = prepare_error_as(state->rstate, state->request,
                                       errcode, state->e_data,
                                       state->typed_e_data,
                                       ((state->client != NULL) ?
                                        state->client->princ : NULL),
                                       &response, state->status);
            state->status = 0;
        }
    }

    if (emsg)
        krb5_free_error_message(kdc_context, emsg);
    if (state->enc_tkt_reply.authorization_data != NULL)
        krb5_free_authdata(kdc_context,
                           state->enc_tkt_reply.authorization_data);
    if (state->server_keyblock.contents != NULL)
        krb5_free_keyblock_contents(kdc_context, &state->server_keyblock);
    if (state->client_keyblock.contents != NULL)
        krb5_free_keyblock_contents(kdc_context, &state->client_keyblock);
    if (state->reply.padata != NULL)
        krb5_free_pa_data(kdc_context, state->reply.padata);
    if (state->reply_encpart.enc_padata)
        krb5_free_pa_data(kdc_context, state->reply_encpart.enc_padata);

    if (state->cname != NULL)
        free(state->cname);
    if (state->sname != NULL)
        free(state->sname);
    krb5_db_free_principal(kdc_context, state->client);
    krb5_db_free_principal(kdc_context, state->server);
    if (state->session_key.contents != NULL)
        krb5_free_keyblock_contents(kdc_context, &state->session_key);
    if (state->ticket_reply.enc_part.ciphertext.data != NULL) {
        memset(state->ticket_reply.enc_part.ciphertext.data , 0,
               state->ticket_reply.enc_part.ciphertext.length);
        free(state->ticket_reply.enc_part.ciphertext.data);
    }

    krb5_free_pa_data(kdc_context, state->e_data);
    krb5_free_data(kdc_context, state->inner_body);
    kdc_free_rstate(state->rstate);
    krb5_free_kdc_req(kdc_context, state->request);
    assert(did_log != 0);

    free(state);
    (*oldrespond)(oldarg, errcode, response);
}
コード例 #4
0
ファイル: do_as_req.c プロジェクト: mrogers950/krb5
static void
finish_process_as_req(struct as_req_state *state, krb5_error_code errcode)
{
    krb5_key_data *server_key;
    krb5_keyblock *as_encrypting_key = NULL;
    krb5_data *response = NULL;
    const char *emsg = 0;
    int did_log = 0;
    loop_respond_fn oldrespond;
    void *oldarg;
    kdc_realm_t *kdc_active_realm = state->active_realm;
    krb5_audit_state *au_state = state->au_state;

    assert(state);
    oldrespond = state->respond;
    oldarg = state->arg;

    if (errcode)
        goto egress;

    au_state->stage = ENCR_REP;

    if ((errcode = validate_forwardable(state->request, *state->client,
                                        *state->server, state->kdc_time,
                                        &state->status))) {
        errcode += ERROR_TABLE_BASE_krb5;
        goto egress;
    }

    errcode = check_indicators(kdc_context, state->server,
                               state->auth_indicators);
    if (errcode) {
        state->status = "HIGHER_AUTHENTICATION_REQUIRED";
        goto egress;
    }

    state->ticket_reply.enc_part2 = &state->enc_tkt_reply;

    /*
     * Find the server key
     */
    if ((errcode = krb5_dbe_find_enctype(kdc_context, state->server,
                                         -1, /* ignore keytype   */
                                         -1, /* Ignore salttype  */
                                         0,  /* Get highest kvno */
                                         &server_key))) {
        state->status = "FINDING_SERVER_KEY";
        goto egress;
    }

    /*
     * Convert server->key into a real key
     * (it may be encrypted in the database)
     *
     *  server_keyblock is later used to generate auth data signatures
     */
    if ((errcode = krb5_dbe_decrypt_key_data(kdc_context, NULL,
                   server_key,
                   &state->server_keyblock,
                   NULL))) {
        state->status = "DECRYPT_SERVER_KEY";
        goto egress;
    }

    /* Start assembling the response */
    state->reply.msg_type = KRB5_AS_REP;
    state->reply.client = state->enc_tkt_reply.client; /* post canonization */
    state->reply.ticket = &state->ticket_reply;
    state->reply_encpart.session = &state->session_key;
    if ((errcode = fetch_last_req_info(state->client,
                                       &state->reply_encpart.last_req))) {
        state->status = "FETCH_LAST_REQ";
        goto egress;
    }
    state->reply_encpart.nonce = state->request->nonce;
    state->reply_encpart.key_exp = get_key_exp(state->client);
    state->reply_encpart.flags = state->enc_tkt_reply.flags;
    state->reply_encpart.server = state->ticket_reply.server;

    /* copy the time fields EXCEPT for authtime; it's location
     *  is used for ktime
     */
    state->reply_encpart.times = state->enc_tkt_reply.times;
    state->reply_encpart.times.authtime = state->authtime = state->kdc_time;

    state->reply_encpart.caddrs = state->enc_tkt_reply.caddrs;
    state->reply_encpart.enc_padata = NULL;

    /* Fetch the padata info to be returned (do this before
     *  authdata to handle possible replacement of reply key
     */
    errcode = return_padata(kdc_context, &state->rock, state->req_pkt,
                            state->request, &state->reply,
                            &state->client_keyblock, &state->pa_context);
    if (errcode) {
        state->status = "KDC_RETURN_PADATA";
        goto egress;
    }

    /* If we didn't find a client long-term key and no preauth mechanism
     * replaced the reply key, error out now. */
    if (state->client_keyblock.enctype == ENCTYPE_NULL) {
        state->status = "CANT_FIND_CLIENT_KEY";
        errcode = KRB5KDC_ERR_ETYPE_NOSUPP;
        goto egress;
    }

    errcode = handle_authdata(kdc_context,
                              state->c_flags,
                              state->client,
                              state->server,
                              NULL,
                              state->local_tgt,
                              &state->client_keyblock,
                              &state->server_keyblock,
                              NULL,
                              state->req_pkt,
                              state->request,
                              NULL, /* for_user_princ */
                              NULL, /* enc_tkt_request */
                              state->auth_indicators,
                              &state->enc_tkt_reply);
    if (errcode) {
        krb5_klog_syslog(LOG_INFO, _("AS_REQ : handle_authdata (%d)"),
                         errcode);
        state->status = "HANDLE_AUTHDATA";
        goto egress;
    }

    errcode = krb5_encrypt_tkt_part(kdc_context, &state->server_keyblock,
                                    &state->ticket_reply);
    if (errcode) {
        state->status = "ENCRYPT_TICKET";
        goto egress;
    }

    errcode = kau_make_tkt_id(kdc_context, &state->ticket_reply,
                              &au_state->tkt_out_id);
    if (errcode) {
        state->status = "GENERATE_TICKET_ID";
        goto egress;
    }

    state->ticket_reply.enc_part.kvno = server_key->key_data_kvno;
    errcode = kdc_fast_response_handle_padata(state->rstate,
              state->request,
              &state->reply,
              state->client_keyblock.enctype);
    if (errcode) {
        state->status = "MAKE_FAST_RESPONSE";
        goto egress;
    }

    /* now encode/encrypt the response */

    state->reply.enc_part.enctype = state->client_keyblock.enctype;

    errcode = kdc_fast_handle_reply_key(state->rstate, &state->client_keyblock,
                                        &as_encrypting_key);
    if (errcode) {
        state->status = "MAKE_FAST_REPLY_KEY";
        goto egress;
    }
    errcode = return_enc_padata(kdc_context, state->req_pkt, state->request,
                                as_encrypting_key, state->server,
                                &state->reply_encpart, FALSE);
    if (errcode) {
        state->status = "KDC_RETURN_ENC_PADATA";
        goto egress;
    }

    if (kdc_fast_hide_client(state->rstate))
        state->reply.client = (krb5_principal)krb5_anonymous_principal();
    errcode = krb5_encode_kdc_rep(kdc_context, KRB5_AS_REP,
                                  &state->reply_encpart, 0,
                                  as_encrypting_key,
                                  &state->reply, &response);
    if (state->client_key != NULL)
        state->reply.enc_part.kvno = state->client_key->key_data_kvno;
    if (errcode) {
        state->status = "ENCODE_KDC_REP";
        goto egress;
    }

    /* these parts are left on as a courtesy from krb5_encode_kdc_rep so we
       can use them in raw form if needed.  But, we don't... */
    memset(state->reply.enc_part.ciphertext.data, 0,
           state->reply.enc_part.ciphertext.length);
    free(state->reply.enc_part.ciphertext.data);

    log_as_req(kdc_context, state->from, state->request, &state->reply,
               state->client, state->cname, state->server,
               state->sname, state->authtime, 0, 0, 0);
    did_log = 1;

egress:
    if (errcode != 0)
        assert (state->status != 0);

    au_state->status = state->status;
    au_state->reply = &state->reply;
    kau_as_req(kdc_context,
               (errcode || state->preauth_err) ? FALSE : TRUE, au_state);
    kau_free_kdc_req(au_state);

    free_padata_context(kdc_context, state->pa_context);
    if (as_encrypting_key)
        krb5_free_keyblock(kdc_context, as_encrypting_key);
    if (errcode)
        emsg = krb5_get_error_message(kdc_context, errcode);

    if (state->status) {
        log_as_req(kdc_context,
                   state->from, state->request, &state->reply, state->client,
                   state->cname, state->server, state->sname, state->authtime,
                   state->status, errcode, emsg);
        did_log = 1;
    }
    if (errcode) {
        if (state->status == 0) {
            state->status = emsg;
        }
        if (errcode != KRB5KDC_ERR_DISCARD) {
            errcode -= ERROR_TABLE_BASE_krb5;
            if (errcode < 0 || errcode > KRB_ERR_MAX)
                errcode = KRB_ERR_GENERIC;

            errcode = prepare_error_as(state->rstate, state->request,
                                       state->local_tgt, errcode,
                                       state->e_data, state->typed_e_data,
                                       ((state->client != NULL) ?
                                        state->client->princ : NULL),
                                       &response, state->status);
            state->status = 0;
        }
    }

    if (emsg)
        krb5_free_error_message(kdc_context, emsg);
    if (state->enc_tkt_reply.authorization_data != NULL)
        krb5_free_authdata(kdc_context,
                           state->enc_tkt_reply.authorization_data);
    if (state->server_keyblock.contents != NULL)
        krb5_free_keyblock_contents(kdc_context, &state->server_keyblock);
    if (state->client_keyblock.contents != NULL)
        krb5_free_keyblock_contents(kdc_context, &state->client_keyblock);
    if (state->reply.padata != NULL)
        krb5_free_pa_data(kdc_context, state->reply.padata);
    if (state->reply_encpart.enc_padata)
        krb5_free_pa_data(kdc_context, state->reply_encpart.enc_padata);

    if (state->cname != NULL)
        free(state->cname);
    if (state->sname != NULL)
        free(state->sname);
    krb5_db_free_principal(kdc_context, state->client);
    krb5_db_free_principal(kdc_context, state->server);
    krb5_db_free_principal(kdc_context, state->local_tgt_storage);
    if (state->session_key.contents != NULL)
        krb5_free_keyblock_contents(kdc_context, &state->session_key);
    if (state->ticket_reply.enc_part.ciphertext.data != NULL) {
        memset(state->ticket_reply.enc_part.ciphertext.data , 0,
               state->ticket_reply.enc_part.ciphertext.length);
        free(state->ticket_reply.enc_part.ciphertext.data);
    }

    krb5_free_pa_data(kdc_context, state->e_data);
    krb5_free_data(kdc_context, state->inner_body);
    kdc_free_rstate(state->rstate);
    krb5_free_kdc_req(kdc_context, state->request);
    k5_free_data_ptr_list(state->auth_indicators);
    assert(did_log != 0);

    free(state);
    (*oldrespond)(oldarg, errcode, response);
}