diff --git a/modules/ssl/mod_ssl.h b/modules/ssl/mod_ssl.h
index 24a65a0..a360911 100644
--- a/modules/ssl/mod_ssl.h
+++ b/modules/ssl/mod_ssl.h
@@ -29,6 +29,7 @@
#include "httpd.h"
#include "http_config.h"
#include "apr_optional.h"
+#include "apr_tables.h" /* for apr_array_header_t */
/* Create a set of SSL_DECLARE(type), SSL_DECLARE_NONSTD(type) and
* SSL_DECLARE_DATA with appropriate export and import tags for the platform
@@ -86,6 +87,34 @@ APR_DECLARE_OPTIONAL_FN(int, ssl_engine_disable, (conn_rec *));
APR_DECLARE_OPTIONAL_FN(int, ssl_engine_set, (conn_rec *,
ap_conf_vector_t *,
int proxy, int enable));
+
+/* Check for availability of new hooks */
+#define SSL_CERT_HOOKS
+#ifdef SSL_CERT_HOOKS
+
+/** Lets others add certificate and key files to the given server.
+ * For each cert a key must also be added.
+ * @param cert_file and array of const char* with the path to the certificate chain
+ * @param key_file and array of const char* with the path to the private key file
+ */
+APR_DECLARE_EXTERNAL_HOOK(ssl, SSL, int, add_cert_files,
+ (server_rec *s, apr_pool_t *p,
+ apr_array_header_t *cert_files,
+ apr_array_header_t *key_files))
+
+/** In case no certificates are available for a server, this
+ * lets other modules add a fallback certificate for the time
+ * being. Regular requests against this server will be answered
+ * with a 503.
+ * @param cert_file and array of const char* with the path to the certificate chain
+ * @param key_file and array of const char* with the path to the private key file
+ */
+APR_DECLARE_EXTERNAL_HOOK(ssl, SSL, int, add_fallback_cert_files,
+ (server_rec *s, apr_pool_t *p,
+ apr_array_header_t *cert_files,
+ apr_array_header_t *key_files))
+
+#endif /* SSL_CERT_HOOKS */
#endif /* __MOD_SSL_H__ */
/** @} */
diff --git a/modules/ssl/mod_ssl_openssl.h b/modules/ssl/mod_ssl_openssl.h
index 0fa654a..d4f684f 100644
--- a/modules/ssl/mod_ssl_openssl.h
+++ b/modules/ssl/mod_ssl_openssl.h
@@ -69,5 +69,45 @@ APR_DECLARE_EXTERNAL_HOOK(ssl, SSL, int, pre_handshake,
APR_DECLARE_EXTERNAL_HOOK(ssl, SSL, int, proxy_post_handshake,
(conn_rec *c, SSL *ssl))
+/** On TLS connections that do not relate to a configured virtual host,
+ * allow other modules to provide a X509 certificate and EVP_PKEY to
+ * be used on the connection. This first hook which does not
+ * return DECLINED will determine the outcome. */
+APR_DECLARE_EXTERNAL_HOOK(ssl, SSL, int, answer_challenge,
+ (conn_rec *c, const char *server_name,
+ X509 **pcert, EVP_PKEY **pkey))
+
+/** During post_config phase, ask around if someone wants to provide
+ * OCSP stapling status information for the given cert (with the also
+ * provided issuer certificate). The first hook which does not
+ * return DECLINED promises to take responsibility (and respond
+ * in later calls via hook ssl_get_stapling_status).
+ * If no hook takes over, mod_ssl's own stapling implementation will
+ * be applied (if configured).
+ */
+APR_DECLARE_EXTERNAL_HOOK(ssl, SSL, int, init_stapling_status,
+ (server_rec *s, apr_pool_t *p,
+ X509 *cert, X509 *issuer))
+
+/** Anyone answering positive to ssl_init_stapling_status for a
+ * certificate, needs to register here and supply the actual OCSP stapling
+ * status data (OCSP_RESP) for a new connection.
+ * A hook supplying the response data must return APR_SUCCESS.
+ * The data is returned in DER encoded bytes via pder and pderlen. The
+ * returned pointer may be NULL, which indicates that data is (currently)
+ * unavailable.
+ * If DER data is returned, it MUST come from a response with
+ * status OCSP_RESPONSE_STATUS_SUCCESSFUL and V_OCSP_CERTSTATUS_GOOD
+ * or V_OCSP_CERTSTATUS_REVOKED, not V_OCSP_CERTSTATUS_UNKNOWN. This means
+ * errors in OCSP retrieval are to be handled/logged by the hook and
+ * are not done by mod_ssl.
+ * Any DER bytes returned MUST be allocated via malloc() and ownership
+ * passes to mod_ssl. Meaning, the hook must return a malloced copy of
+ * the data it has. mod_ssl (or OpenSSL) will free it.
+ */
+APR_DECLARE_EXTERNAL_HOOK(ssl, SSL, int, get_stapling_status,
+ (unsigned char **pder, int *pderlen,
+ conn_rec *c, server_rec *s, X509 *cert))
+
#endif /* __MOD_SSL_OPENSSL_H__ */
/** @} */
diff --git a/modules/ssl/ssl_engine_init.c b/modules/ssl/ssl_engine_init.c
index 21e41e2..ef631c1 100644
--- a/modules/ssl/ssl_engine_init.c
+++ b/modules/ssl/ssl_engine_init.c
@@ -36,6 +36,25 @@ APR_IMPLEMENT_OPTIONAL_HOOK_RUN_ALL(ssl, SSL, int, init_server,
(server_rec *s,apr_pool_t *p,int is_proxy,SSL_CTX *ctx),
(s,p,is_proxy,ctx), OK, DECLINED)
+APR_IMPLEMENT_OPTIONAL_HOOK_RUN_ALL(ssl, SSL, int, add_cert_files,
+ (server_rec *s, apr_pool_t *p,
+ apr_array_header_t *cert_files, apr_array_header_t *key_files),
+ (s, p, cert_files, key_files),
+ OK, DECLINED)
+
+APR_IMPLEMENT_OPTIONAL_HOOK_RUN_ALL(ssl, SSL, int, add_fallback_cert_files,
+ (server_rec *s, apr_pool_t *p,
+ apr_array_header_t *cert_files, apr_array_header_t *key_files),
+ (s, p, cert_files, key_files),
+ OK, DECLINED)
+
+APR_IMPLEMENT_OPTIONAL_HOOK_RUN_ALL(ssl, SSL, int, answer_challenge,
+ (conn_rec *c, const char *server_name,
+ X509 **pcert, EVP_PKEY **pkey),
+ (c, server_name, pcert, pkey),
+ DECLINED, DECLINED)
+
+
/* _________________________________________________________________
**
** Module Initialization
@@ -165,18 +184,18 @@ static void ssl_add_version_components(apr_pool_t *p,
modver, AP_SERVER_BASEVERSION, incver);
}
-/**************************************************************************************************/
-/* Managed Domains Interface */
-
-static APR_OPTIONAL_FN_TYPE(md_is_managed) *md_is_managed;
-static APR_OPTIONAL_FN_TYPE(md_get_certificate) *md_get_certificate;
-static APR_OPTIONAL_FN_TYPE(md_is_challenge) *md_is_challenge;
+/* _________________________________________________________________
+**
+** Let other answer special connection attempts.
+** Used in ACME challenge handling by mod_md.
+** _________________________________________________________________
+*/
int ssl_is_challenge(conn_rec *c, const char *servername,
X509 **pcert, EVP_PKEY **pkey)
{
- if (md_is_challenge) {
- return md_is_challenge(c, servername, pcert, pkey);
+ if (APR_SUCCESS == ssl_run_answer_challenge(c, servername, pcert, pkey)) {
+ return 1;
}
*pcert = NULL;
*pkey = NULL;
@@ -231,16 +250,6 @@ apr_status_t ssl_init_Module(apr_pool_t *p, apr_pool_t *plog,
ssl_config_global_create(base_server); /* just to avoid problems */
ssl_config_global_fix(mc);
- /* Initialize our interface to mod_md, if it is loaded
- */
- md_is_managed = APR_RETRIEVE_OPTIONAL_FN(md_is_managed);
- md_get_certificate = APR_RETRIEVE_OPTIONAL_FN(md_get_certificate);
- md_is_challenge = APR_RETRIEVE_OPTIONAL_FN(md_is_challenge);
- if (!md_is_managed || !md_get_certificate) {
- md_is_managed = NULL;
- md_get_certificate = NULL;
- }
-
/*
* try to fix the configuration and open the dedicated SSL
* logfile as early as possible
@@ -1392,8 +1401,7 @@ static apr_status_t ssl_init_server_certs(server_rec *s,
* loaded via SSLOpenSSLConfCmd Certificate), so for 1.0.2 and
* later, we defer to the code in ssl_init_server_ctx.
*/
- if ((mctx->stapling_enabled == TRUE) &&
- !ssl_stapling_init_cert(s, p, ptemp, mctx, cert)) {
+ if (!ssl_stapling_init_cert(s, p, ptemp, mctx, cert)) {
ap_log_error(APLOG_MARK, APLOG_ERR, 0, s, APLOGNO(02567)
"Unable to configure certificate %s for stapling",
key_id);
@@ -1788,11 +1796,13 @@ static apr_status_t ssl_init_server_ctx(server_rec *s,
apr_array_header_t *pphrases)
{
apr_status_t rv;
+ modssl_pk_server_t *pks;
#ifdef HAVE_SSL_CONF_CMD
ssl_ctx_param_t *param = (ssl_ctx_param_t *)sc->server->ssl_ctx_param->elts;
SSL_CONF_CTX *cctx = sc->server->ssl_ctx_config;
int i;
#endif
+ int n;
/*
* Check for problematic re-initializations
@@ -1804,50 +1814,24 @@ static apr_status_t ssl_init_server_ctx(server_rec *s,
return APR_EGENERAL;
}
- ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, s, APLOGNO(10083)
- "Init: (%s) mod_md support is %s.", ssl_util_vhostid(p, s),
- md_is_managed? "available" : "unavailable");
- if (md_is_managed && md_is_managed(s)) {
- modssl_pk_server_t *const pks = sc->server->pks;
- if (pks->cert_files->nelts > 0 || pks->key_files->nelts > 0) {
- ap_log_error(APLOG_MARK, APLOG_WARNING, 0, s, APLOGNO(10084)
- "Init: (%s) You configured certificate/key files on this host, but "
- "is is covered by a Managed Domain. You need to remove these directives "
- "for the Managed Domain to take over.", ssl_util_vhostid(p, s));
- }
- else {
- const char *key_file, *cert_file, *chain_file;
-
- key_file = cert_file = chain_file = NULL;
-
- if (md_get_certificate) {
- rv = md_get_certificate(s, p, &key_file, &cert_file);
- }
- else {
- rv = APR_ENOTIMPL;
- }
-
- if (key_file && cert_file) {
- ap_log_error(APLOG_MARK, APLOG_TRACE1, 0, s,
- "%s: installing key=%s, cert=%s, chain=%s",
- ssl_util_vhostid(p, s), key_file, cert_file, chain_file);
- APR_ARRAY_PUSH(pks->key_files, const char *) = key_file;
- APR_ARRAY_PUSH(pks->cert_files, const char *) = cert_file;
- sc->server->cert_chain = chain_file;
- }
-
- if (APR_STATUS_IS_EAGAIN(rv)) {
- /* Managed Domain not ready yet. This is not a reason to fail the config */
- ap_log_error(APLOG_MARK, APLOG_WARNING, 0, s, APLOGNO(10085)
- "Init: %s will respond with '503 Service Unavailable' for now. This "
- "host is part of a Managed Domain, but no SSL certificate is "
- "available (yet).", ssl_util_vhostid(p, s));
- pks->service_unavailable = 1;
- }
- else if (rv != APR_SUCCESS) {
- return rv;
- }
- }
+ /* Allow others to provide certificate files */
+ pks = sc->server->pks;
+ n = pks->cert_files->nelts;
+ ssl_run_add_cert_files(s, p, pks->cert_files, pks->key_files);
+
+ if (n < pks->cert_files->nelts) {
+ /* this overrides any old chain configuration */
+ sc->server->cert_chain = NULL;
+ }
+
+ if (apr_is_empty_array(pks->cert_files) && !sc->server->cert_chain) {
+ ssl_run_add_fallback_cert_files(s, p, pks->cert_files, pks->key_files);
+
+ pks->service_unavailable = 1;
+ ap_log_error(APLOG_MARK, APLOG_WARNING, 0, s, APLOGNO(10085)
+ "Init: %s will respond with '503 Service Unavailable' for now. There "
+ "are no SSL certificates configured and no other module contributed any.",
+ ssl_util_vhostid(p, s));
}
if ((rv = ssl_init_ctx(s, p, ptemp, sc->server)) != APR_SUCCESS) {
@@ -1900,7 +1884,7 @@ static apr_status_t ssl_init_server_ctx(server_rec *s,
* (late) point makes sure that we catch both certificates loaded
* via SSLCertificateFile and SSLOpenSSLConfCmd Certificate.
*/
- if (sc->server->stapling_enabled == TRUE) {
+ do {
X509 *cert;
int i = 0;
int ret = SSL_CTX_set_current_cert(sc->server->ssl_ctx,
@@ -1917,7 +1901,7 @@ static apr_status_t ssl_init_server_ctx(server_rec *s,
SSL_CERT_SET_NEXT);
i++;
}
- }
+ } while(0);
#endif
#ifdef HAVE_TLS_SESSION_TICKETS
diff --git a/modules/ssl/ssl_engine_kernel.c b/modules/ssl/ssl_engine_kernel.c
index e6a9f67..a5e86e4 100644
--- a/modules/ssl/ssl_engine_kernel.c
+++ b/modules/ssl/ssl_engine_kernel.c
@@ -2303,6 +2303,37 @@ void ssl_callback_Info(const SSL *ssl, int where, int rc)
}
#ifdef HAVE_TLSEXT
+
+static apr_status_t set_challenge_creds(conn_rec *c, const char *servername,
+ SSL *ssl, X509 *cert, EVP_PKEY *key)
+{
+ SSLConnRec *sslcon = myConnConfig(c);
+
+ sslcon->service_unavailable = 1;
+ if ((SSL_use_certificate(ssl, cert) < 1)) {
+ ap_log_cerror(APLOG_MARK, APLOG_WARNING, 0, c, APLOGNO(10086)
+ "Failed to configure challenge certificate %s",
+ servername);
+ return APR_EGENERAL;
+ }
+
+ if (!SSL_use_PrivateKey(ssl, key)) {
+ ap_log_cerror(APLOG_MARK, APLOG_WARNING, 0, c, APLOGNO(10087)
+ "error '%s' using Challenge key: %s",
+ ERR_error_string(ERR_peek_last_error(), NULL),
+ servername);
+ return APR_EGENERAL;
+ }
+
+ if (SSL_check_private_key(ssl) < 1) {
+ ap_log_cerror(APLOG_MARK, APLOG_WARNING, 0, c, APLOGNO(10088)
+ "Challenge certificate and private key %s "
+ "do not match", servername);
+ return APR_EGENERAL;
+ }
+ return APR_SUCCESS;
+}
+
/*
* This function sets the virtual host from an extended
* client hello with a server name indication extension ("SNI", cf. RFC 6066).
@@ -2332,30 +2363,12 @@ static apr_status_t init_vhost(conn_rec *c, SSL *ssl)
return APR_SUCCESS;
}
else if (ssl_is_challenge(c, servername, &cert, &key)) {
-
- sslcon->service_unavailable = 1;
- if ((SSL_use_certificate(ssl, cert) < 1)) {
- ap_log_cerror(APLOG_MARK, APLOG_WARNING, 0, c, APLOGNO(10086)
- "Failed to configure challenge certificate %s",
- servername);
+ /* With ACMEv1 we can have challenge connections to a unknown domains
+ * that need to be answered with a special certificate and will
+ * otherwise not answer any requests. */
+ if (set_challenge_creds(c, servername, ssl, cert, key) != APR_SUCCESS) {
return APR_EGENERAL;
}
-
- if (!SSL_use_PrivateKey(ssl, key)) {
- ap_log_cerror(APLOG_MARK, APLOG_WARNING, 0, c, APLOGNO(10087)
- "error '%s' using Challenge key: %s",
- ERR_error_string(ERR_peek_last_error(), NULL),
- servername);
- return APR_EGENERAL;
- }
-
- if (SSL_check_private_key(ssl) < 1) {
- ap_log_cerror(APLOG_MARK, APLOG_WARNING, 0, c, APLOGNO(10088)
- "Challenge certificate and private key %s "
- "do not match", servername);
- return APR_EGENERAL;
- }
-
}
else {
ap_log_cerror(APLOG_MARK, APLOG_DEBUG, 0, c, APLOGNO(02044)
@@ -2648,6 +2661,23 @@ int ssl_callback_alpn_select(SSL *ssl,
proposed);
return SSL_TLSEXT_ERR_ALERT_FATAL;
}
+
+ /* protocol was switched, this could be a challenge protocol such as "acme-tls/1".
+ * For that to work, we need to allow overrides to our ssl certificate.
+ * However, exclude challenge checks on our best known traffic protocol.
+ * (http/1.1 is the default, we never switch to it anyway.)
+ */
+ if (strcmp("h2", proposed)) {
+ const char *servername = SSL_get_servername(ssl, TLSEXT_NAMETYPE_host_name);
+ X509 *cert;
+ EVP_PKEY *key;
+
+ if (ssl_is_challenge(c, servername, &cert, &key)) {
+ if (set_challenge_creds(c, servername, ssl, cert, key) != APR_SUCCESS) {
+ return SSL_TLSEXT_ERR_ALERT_FATAL;
+ }
+ }
+ }
}
return SSL_TLSEXT_ERR_OK;
diff --git a/modules/ssl/ssl_util_stapling.c b/modules/ssl/ssl_util_stapling.c
index c3e2cfa..4df0a9a 100644
--- a/modules/ssl/ssl_util_stapling.c
+++ b/modules/ssl/ssl_util_stapling.c
@@ -31,12 +31,28 @@
#include "ssl_private.h"
#include "ap_mpm.h"
#include "apr_thread_mutex.h"
+#include "mod_ssl_openssl.h"
+
+APR_IMPLEMENT_OPTIONAL_HOOK_RUN_ALL(ssl, SSL, int, init_stapling_status,
+ (server_rec *s, apr_pool_t *p,
+ X509 *cert, X509 *issuer),
+ (s, p, cert, issuer),
+ DECLINED, DECLINED)
+
+APR_IMPLEMENT_OPTIONAL_HOOK_RUN_ALL(ssl, SSL, int, get_stapling_status,
+ (unsigned char **pder, int *pderlen,
+ conn_rec *c, server_rec *s, X509 *cert),
+ (pder, pderlen, c, s, cert),
+ DECLINED, DECLINED)
+
#ifdef HAVE_OCSP_STAPLING
static int stapling_cache_mutex_on(server_rec *s);
static int stapling_cache_mutex_off(server_rec *s);
+static int stapling_cb(SSL *ssl, void *arg);
+
/**
* Maxiumum OCSP stapling response size. This should be the response for a
* single certificate and will typically include the responder certificate chain
@@ -119,7 +135,38 @@ int ssl_stapling_init_cert(server_rec *s, apr_pool_t *p, apr_pool_t *ptemp,
OCSP_CERTID *cid = NULL;
STACK_OF(OPENSSL_STRING) *aia = NULL;
- if ((x == NULL) || (X509_digest(x, EVP_sha1(), idx, NULL) != 1))
+ if (x == NULL)
+ return 0;
+
+ if (!(issuer = stapling_get_issuer(mctx, x))) {
+ /* In Apache pre 2.4.40, we use to come here only when mod_ssl stapling
+ * was enabled. With the new hooks, we give other modules the chance
+ * to provide stapling status. However, we do not want to log ssl errors
+ * where we did not do so in the past. */
+ if (mctx->stapling_enabled == TRUE) {
+ ssl_log_xerror(SSLLOG_MARK, APLOG_ERR, 0, ptemp, s, x, APLOGNO(02217)
+ "ssl_stapling_init_cert: can't retrieve issuer "
+ "certificate!");
+ return 0;
+ }
+ return 1;
+ }
+
+ if (ssl_run_init_stapling_status(s, p, x, issuer) == APR_SUCCESS) {
+ /* Someone's taken over or mod_ssl's own implementation is not enabled */
+ if (mctx->stapling_enabled != TRUE) {
+ SSL_CTX_set_tlsext_status_cb(mctx->ssl_ctx, stapling_cb);
+ ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, s, APLOGNO() "OCSP stapling added via hook");
+ }
+ return 1;
+ }
+
+ if (mctx->stapling_enabled != TRUE) {
+ /* mod_ssl's own implementation is not enabled */
+ return 1;
+ }
+
+ if (X509_digest(x, EVP_sha1(), idx, NULL) != 1)
return 0;
cinf = apr_hash_get(stapling_certinfo, idx, sizeof(idx));
@@ -139,13 +186,6 @@ int ssl_stapling_init_cert(server_rec *s, apr_pool_t *p, apr_pool_t *ptemp,
return 1;
}
- if (!(issuer = stapling_get_issuer(mctx, x))) {
- ssl_log_xerror(SSLLOG_MARK, APLOG_ERR, 0, ptemp, s, x, APLOGNO(02217)
- "ssl_stapling_init_cert: can't retrieve issuer "
- "certificate!");
- return 0;
- }
-
cid = OCSP_cert_to_id(NULL, x, issuer);
X509_free(issuer);
if (!cid) {
@@ -182,18 +222,16 @@ int ssl_stapling_init_cert(server_rec *s, apr_pool_t *p, apr_pool_t *ptemp,
mctx->sc->vhost_id);
apr_hash_set(stapling_certinfo, cinf->idx, sizeof(cinf->idx), cinf);
-
+
return 1;
}
-static certinfo *stapling_get_certinfo(server_rec *s, modssl_ctx_t *mctx,
+static certinfo *stapling_get_certinfo(server_rec *s, X509 *x, modssl_ctx_t *mctx,
SSL *ssl)
{
certinfo *cinf;
- X509 *x;
UCHAR idx[SHA_DIGEST_LENGTH];
- x = SSL_get_certificate(ssl);
- if ((x == NULL) || (X509_digest(x, EVP_sha1(), idx, NULL) != 1))
+ if (X509_digest(x, EVP_sha1(), idx, NULL) != 1)
return NULL;
cinf = apr_hash_get(stapling_certinfo, idx, sizeof(idx));
if (cinf && cinf->cid)
@@ -750,18 +788,34 @@ static int stapling_cb(SSL *ssl, void *arg)
OCSP_RESPONSE *rsp = NULL;
int rv;
BOOL ok = TRUE;
+ X509 *x;
+ unsigned char *rspder = NULL;
+ int rspderlen;
+ ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, s, APLOGNO(01951)
+ "stapling_cb: OCSP Stapling callback called");
+
+ x = SSL_get_certificate(ssl);
+ if (x == NULL) {
+ return SSL_TLSEXT_ERR_NOACK;
+ }
+
+ if (ssl_run_get_stapling_status(&rspder, &rspderlen, conn, s, x) == APR_SUCCESS) {
+ /* a hook handles stapling for this certicate and determines the response */
+ if (rspder == NULL || rspderlen <= 0) {
+ return SSL_TLSEXT_ERR_NOACK;
+ }
+ SSL_set_tlsext_status_ocsp_resp(ssl, rspder, rspderlen);
+ return SSL_TLSEXT_ERR_OK;
+ }
+
if (sc->server->stapling_enabled != TRUE) {
ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, s, APLOGNO(01950)
"stapling_cb: OCSP Stapling disabled");
return SSL_TLSEXT_ERR_NOACK;
}
- ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, s, APLOGNO(01951)
- "stapling_cb: OCSP Stapling callback called");
-
- cinf = stapling_get_certinfo(s, mctx, ssl);
- if (cinf == NULL) {
+ if ((cinf = stapling_get_certinfo(s, x, mctx, ssl)) == NULL) {
return SSL_TLSEXT_ERR_NOACK;
}
@@ -864,9 +918,10 @@ apr_status_t modssl_init_stapling(server_rec *s, apr_pool_t *p,
if (mctx->stapling_responder_timeout == UNSET) {
mctx->stapling_responder_timeout = 10 * APR_USEC_PER_SEC;
}
+
SSL_CTX_set_tlsext_status_cb(ctx, stapling_cb);
ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, s, APLOGNO(01960) "OCSP stapling initialized");
-
+
return APR_SUCCESS;
}