Adding upstream version 2.4.38.upstream/2.4.38

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 1252 insertions, 0 deletions

diff --git a/modules/ssl/ssl_engine_vars.c b/modules/ssl/ssl_engine_vars.c
new file mode 100644
index 0000000..5724f18
--- /dev/null
+++ b/modules/ssl/ssl_engine_vars.c
@@ -0,0 +1,1252 @@
+/* Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+/*                      _             _
+ *  _ __ ___   ___   __| |    ___ ___| |  mod_ssl
+ * | '_ ` _ \ / _ \ / _` |   / __/ __| |  Apache Interface to OpenSSL
+ * | | | | | | (_) | (_| |   \__ \__ \ |
+ * |_| |_| |_|\___/ \__,_|___|___/___/_|
+ *                      |_____|
+ *  ssl_engine_vars.c
+ *  Variable Lookup Facility
+ */
+                             /* ``Those of you who think they
+                                  know everything are very annoying
+                                  to those of us who do.''
+                                                  -- Unknown       */
+#include "ssl_private.h"
+#include "mod_ssl.h"
+#include "ap_expr.h"
+
+#include "apr_time.h"
+
+/*  _________________________________________________________________
+**
+**  Variable Lookup
+**  _________________________________________________________________
+*/
+
+static char *ssl_var_lookup_ssl(apr_pool_t *p, SSLConnRec *sslconn, request_rec *r, char *var);
+static char *ssl_var_lookup_ssl_cert(apr_pool_t *p, request_rec *r, X509 *xs, char *var);
+static char *ssl_var_lookup_ssl_cert_dn(apr_pool_t *p, X509_NAME *xsname, const char *var);
+static char *ssl_var_lookup_ssl_cert_san(apr_pool_t *p, X509 *xs, char *var);
+static char *ssl_var_lookup_ssl_cert_valid(apr_pool_t *p, ASN1_TIME *tm);
+static char *ssl_var_lookup_ssl_cert_remain(apr_pool_t *p, ASN1_TIME *tm);
+static char *ssl_var_lookup_ssl_cert_serial(apr_pool_t *p, X509 *xs);
+static char *ssl_var_lookup_ssl_cert_chain(apr_pool_t *p, STACK_OF(X509) *sk, char *var);
+static char *ssl_var_lookup_ssl_cert_rfc4523_cea(apr_pool_t *p, SSL *ssl);
+static char *ssl_var_lookup_ssl_cert_PEM(apr_pool_t *p, X509 *xs);
+static char *ssl_var_lookup_ssl_cert_verify(apr_pool_t *p, SSLConnRec *sslconn);
+static char *ssl_var_lookup_ssl_cipher(apr_pool_t *p, SSLConnRec *sslconn, char *var);
+static void  ssl_var_lookup_ssl_cipher_bits(SSL *ssl, int *usekeysize, int *algkeysize);
+static char *ssl_var_lookup_ssl_version(apr_pool_t *p, char *var);
+static char *ssl_var_lookup_ssl_compress_meth(SSL *ssl);
+
+static SSLConnRec *ssl_get_effective_config(conn_rec *c)
+{
+    SSLConnRec *sslconn = myConnConfig(c);
+    if (!(sslconn && sslconn->ssl) && c->master) {
+        /* use master connection if no SSL defined here */
+        sslconn = myConnConfig(c->master);
+    }
+    return sslconn;
+}
+
+static int ssl_is_https(conn_rec *c)
+{
+    SSLConnRec *sslconn = ssl_get_effective_config(c);
+    return sslconn && sslconn->ssl;
+}
+
+static const char var_interface[] = "mod_ssl/" AP_SERVER_BASEREVISION;
+static char var_library_interface[] = MODSSL_LIBRARY_TEXT;
+static char *var_library = NULL;
+
+static apr_array_header_t *expr_peer_ext_list_fn(ap_expr_eval_ctx_t *ctx,
+                                                 const void *dummy,
+                                                 const char *arg)
+{
+    return ssl_ext_list(ctx->p, ctx->c, 1, arg);
+}
+
+static const char *expr_var_fn(ap_expr_eval_ctx_t *ctx, const void *data)
+{
+    char *var = (char *)data;
+    SSLConnRec *sslconn = ssl_get_effective_config(ctx->c);
+
+    return sslconn ? ssl_var_lookup_ssl(ctx->p, sslconn, ctx->r, var) : NULL;
+}
+
+static const char *expr_func_fn(ap_expr_eval_ctx_t *ctx, const void *data,
+                                const char *arg)
+{
+    char *var = (char *)arg;
+
+    return var ? ssl_var_lookup(ctx->p, ctx->s, ctx->c, ctx->r, var) : NULL;
+}
+
+static int ssl_expr_lookup(ap_expr_lookup_parms *parms)
+{
+    switch (parms->type) {
+    case AP_EXPR_FUNC_VAR:
+        /* for now, we just handle everything that starts with SSL_, but
+         * register our hook as APR_HOOK_LAST
+         * XXX: This can be optimized
+         */
+        if (strcEQn(parms->name, "SSL_", 4)) {
+            *parms->func = expr_var_fn;
+            *parms->data = parms->name + 4;
+            return OK;
+        }
+        break;
+    case AP_EXPR_FUNC_STRING:
+        /* Function SSL() is implemented by us.
+         */
+        if (strcEQ(parms->name, "SSL")) {
+            *parms->func = expr_func_fn;
+            *parms->data = NULL;
+            return OK;
+        }
+        break;
+    case AP_EXPR_FUNC_LIST:
+        if (strcEQ(parms->name, "PeerExtList")) {
+            *parms->func = expr_peer_ext_list_fn;
+            *parms->data = "PeerExtList";
+            return OK;
+        }
+        break;
+    }
+    return DECLINED;
+}
+
+
+void ssl_var_register(apr_pool_t *p)
+{
+    char *cp, *cp2;
+
+    APR_REGISTER_OPTIONAL_FN(ssl_is_https);
+    APR_REGISTER_OPTIONAL_FN(ssl_var_lookup);
+    APR_REGISTER_OPTIONAL_FN(ssl_ext_list);
+
+    /* Perform once-per-process library version determination: */
+    var_library = apr_pstrdup(p, MODSSL_LIBRARY_DYNTEXT);
+
+    if ((cp = strchr(var_library, ' ')) != NULL) {
+        *cp = '/';
+        if ((cp2 = strchr(cp, ' ')) != NULL)
+            *cp2 = NUL;
+    }
+
+    if ((cp = strchr(var_library_interface, ' ')) != NULL) {
+        *cp = '/';
+        if ((cp2 = strchr(cp, ' ')) != NULL)
+            *cp2 = NUL;
+    }
+
+    ap_hook_expr_lookup(ssl_expr_lookup, NULL, NULL, APR_HOOK_MIDDLE);
+}
+
+/* This function must remain safe to use for a non-SSL connection. */
+char *ssl_var_lookup(apr_pool_t *p, server_rec *s, conn_rec *c, request_rec *r, char *var)
+{
+    SSLModConfigRec *mc = myModConfig(s);
+    const char *result;
+    BOOL resdup;
+    apr_time_exp_t tm;
+
+    result = NULL;
+    resdup = TRUE;
+
+    /*
+     * When no pool is given try to find one
+     */
+    if (p == NULL) {
+        if (r != NULL)
+            p = r->pool;
+        else if (c != NULL)
+            p = c->pool;
+        else
+            p = mc->pPool;
+    }
+
+    /*
+     * Request dependent stuff
+     */
+    if (r != NULL) {
+        switch (var[0]) {
+        case 'H':
+        case 'h':
+            if (strcEQ(var, "HTTP_USER_AGENT"))
+                result = apr_table_get(r->headers_in, "User-Agent");
+            else if (strcEQ(var, "HTTP_REFERER"))
+                result = apr_table_get(r->headers_in, "Referer");
+            else if (strcEQ(var, "HTTP_COOKIE"))
+                result = apr_table_get(r->headers_in, "Cookie");
+            else if (strcEQ(var, "HTTP_FORWARDED"))
+                result = apr_table_get(r->headers_in, "Forwarded");
+            else if (strcEQ(var, "HTTP_HOST"))
+                result = apr_table_get(r->headers_in, "Host");
+            else if (strcEQ(var, "HTTP_PROXY_CONNECTION"))
+                result = apr_table_get(r->headers_in, "Proxy-Connection");
+            else if (strcEQ(var, "HTTP_ACCEPT"))
+                result = apr_table_get(r->headers_in, "Accept");
+            else if (strlen(var) > 5 && strcEQn(var, "HTTP:", 5))
+                /* all other headers from which we are still not know about */
+                result = apr_table_get(r->headers_in, var+5);
+            break;
+
+        case 'R':
+        case 'r':
+            if (strcEQ(var, "REQUEST_METHOD"))
+                result = r->method;
+            else if (strcEQ(var, "REQUEST_SCHEME"))
+                result = ap_http_scheme(r);
+            else if (strcEQ(var, "REQUEST_URI"))
+                result = r->uri;
+            else if (strcEQ(var, "REQUEST_FILENAME"))
+                result = r->filename;
+            else if (strcEQ(var, "REMOTE_ADDR"))
+                result = r->useragent_ip;
+            else if (strcEQ(var, "REMOTE_HOST"))
+                result = ap_get_useragent_host(r, REMOTE_NAME, NULL);
+            else if (strcEQ(var, "REMOTE_IDENT"))
+                result = ap_get_remote_logname(r);
+            else if (strcEQ(var, "REMOTE_USER"))
+                result = r->user;
+            break;
+
+        case 'S':
+        case 's':
+            if (strcEQn(var, "SSL", 3)) break; /* shortcut common case */
+
+            if (strcEQ(var, "SERVER_ADMIN"))
+                result = r->server->server_admin;
+            else if (strcEQ(var, "SERVER_NAME"))
+                result = ap_get_server_name_for_url(r);
+            else if (strcEQ(var, "SERVER_PORT"))
+                result = apr_psprintf(p, "%u", ap_get_server_port(r));
+            else if (strcEQ(var, "SERVER_PROTOCOL"))
+                result = r->protocol;
+            else if (strcEQ(var, "SCRIPT_FILENAME"))
+                result = r->filename;
+            break;
+
+        default:
+            if (strcEQ(var, "PATH_INFO"))
+                result = r->path_info;
+            else if (strcEQ(var, "QUERY_STRING"))
+                result = r->args;
+            else if (strcEQ(var, "IS_SUBREQ"))
+                result = (r->main != NULL ? "true" : "false");
+            else if (strcEQ(var, "DOCUMENT_ROOT"))
+                result = ap_document_root(r);
+            else if (strcEQ(var, "AUTH_TYPE"))
+                result = r->ap_auth_type;
+            else if (strcEQ(var, "THE_REQUEST"))
+                result = r->the_request;
+            else if (strlen(var) > 4 && strcEQn(var, "ENV:", 4)) {
+                result = apr_table_get(r->notes, var+4);
+                if (result == NULL)
+                    result = apr_table_get(r->subprocess_env, var+4);
+            }
+            break;
+        }
+    }
+
+    /*
+     * Connection stuff
+     */
+    if (result == NULL && c != NULL) {
+        SSLConnRec *sslconn = ssl_get_effective_config(c);
+        if (strlen(var) > 4 && strcEQn(var, "SSL_", 4)
+            && sslconn && sslconn->ssl)
+            result = ssl_var_lookup_ssl(p, sslconn, r, var+4);
+        else if (strcEQ(var, "HTTPS")) {
+            if (sslconn && sslconn->ssl)
+                result = "on";
+            else
+                result = "off";
+        }
+    }
+
+    /*
+     * Totally independent stuff
+     */
+    if (result == NULL) {
+        if (strlen(var) > 12 && strcEQn(var, "SSL_VERSION_", 12))
+            result = ssl_var_lookup_ssl_version(p, var+12);
+        else if (strcEQ(var, "SERVER_SOFTWARE"))
+            result = ap_get_server_banner();
+        else if (strcEQ(var, "API_VERSION")) {
+            result = apr_itoa(p, MODULE_MAGIC_NUMBER_MAJOR);
+            resdup = FALSE;
+        }
+        else if (strcEQ(var, "TIME_YEAR")) {
+            apr_time_exp_lt(&tm, apr_time_now());
+            result = apr_psprintf(p, "%02d%02d",
+                                 (tm.tm_year / 100) + 19, tm.tm_year % 100);
+            resdup = FALSE;
+        }
+#define MKTIMESTR(format, tmfield) \
+            apr_time_exp_lt(&tm, apr_time_now()); \
+            result = apr_psprintf(p, format, tm.tmfield); \
+            resdup = FALSE;
+        else if (strcEQ(var, "TIME_MON")) {
+            MKTIMESTR("%02d", tm_mon+1)
+        }
+        else if (strcEQ(var, "TIME_DAY")) {
+            MKTIMESTR("%02d", tm_mday)
+        }
+        else if (strcEQ(var, "TIME_HOUR")) {
+            MKTIMESTR("%02d", tm_hour)
+        }
+        else if (strcEQ(var, "TIME_MIN")) {
+            MKTIMESTR("%02d", tm_min)
+        }
+        else if (strcEQ(var, "TIME_SEC")) {
+            MKTIMESTR("%02d", tm_sec)
+        }
+        else if (strcEQ(var, "TIME_WDAY")) {
+            MKTIMESTR("%d", tm_wday)
+        }
+        else if (strcEQ(var, "TIME")) {
+            apr_time_exp_lt(&tm, apr_time_now());
+            result = apr_psprintf(p,
+                        "%02d%02d%02d%02d%02d%02d%02d", (tm.tm_year / 100) + 19,
+                        (tm.tm_year % 100), tm.tm_mon+1, tm.tm_mday,
+                        tm.tm_hour, tm.tm_min, tm.tm_sec);
+            resdup = FALSE;
+        }
+        /* all other env-variables from the parent Apache process */
+        else if (strlen(var) > 4 && strcEQn(var, "ENV:", 4)) {
+            result = getenv(var+4);
+        }
+    }
+
+    if (result != NULL && resdup)
+        result = apr_pstrdup(p, result);
+    if (result == NULL)
+        result = "";
+    return (char *)result;
+}
+
+static char *ssl_var_lookup_ssl(apr_pool_t *p, SSLConnRec *sslconn, 
+                                request_rec *r, char *var)
+{
+    char *result;
+    X509 *xs;
+    STACK_OF(X509) *sk;
+    SSL *ssl;
+
+    result = NULL;
+
+    ssl = sslconn->ssl;
+    if (strlen(var) > 8 && strcEQn(var, "VERSION_", 8)) {
+        result = ssl_var_lookup_ssl_version(p, var+8);
+    }
+    else if (ssl != NULL && strcEQ(var, "PROTOCOL")) {
+        result = (char *)SSL_get_version(ssl);
+    }
+    else if (ssl != NULL && strcEQ(var, "SESSION_ID")) {
+        char buf[MODSSL_SESSION_ID_STRING_LEN];
+        SSL_SESSION *pSession = SSL_get_session(ssl);
+        if (pSession) {
+            IDCONST unsigned char *id;
+            unsigned int idlen;
+
+#ifdef OPENSSL_NO_SSL_INTERN
+            id = (unsigned char *)SSL_SESSION_get_id(pSession, &idlen);
+#else
+            id = pSession->session_id;
+            idlen = pSession->session_id_length;
+#endif
+
+            result = apr_pstrdup(p, modssl_SSL_SESSION_id2sz(id, idlen,
+                                                             buf, sizeof(buf)));
+        }
+    }
+    else if(ssl != NULL && strcEQ(var, "SESSION_RESUMED")) {
+        if (SSL_session_reused(ssl) == 1)
+            result = "Resumed";
+        else
+            result = "Initial";
+    }
+    else if (ssl != NULL && strlen(var) >= 6 && strcEQn(var, "CIPHER", 6)) {
+        result = ssl_var_lookup_ssl_cipher(p, sslconn, var+6);
+    }
+    else if (ssl != NULL && strlen(var) > 18 && strcEQn(var, "CLIENT_CERT_CHAIN_", 18)) {
+        sk = SSL_get_peer_cert_chain(ssl);
+        result = ssl_var_lookup_ssl_cert_chain(p, sk, var+18);
+    }
+    else if (ssl != NULL && strcEQ(var, "CLIENT_CERT_RFC4523_CEA")) {
+        result = ssl_var_lookup_ssl_cert_rfc4523_cea(p, ssl);
+    }
+    else if (ssl != NULL && strcEQ(var, "CLIENT_VERIFY")) {
+        result = ssl_var_lookup_ssl_cert_verify(p, sslconn);
+    }
+    else if (ssl != NULL && strlen(var) > 7 && strcEQn(var, "CLIENT_", 7)) {
+        if ((xs = SSL_get_peer_certificate(ssl)) != NULL) {
+            result = ssl_var_lookup_ssl_cert(p, r, xs, var+7);
+            X509_free(xs);
+        }
+    }
+    else if (ssl != NULL && strlen(var) > 7 && strcEQn(var, "SERVER_", 7)) {
+        if ((xs = SSL_get_certificate(ssl)) != NULL) {
+            result = ssl_var_lookup_ssl_cert(p, r, xs, var+7);
+            /* SSL_get_certificate is different from SSL_get_peer_certificate.
+             * No need to X509_free(xs).
+             */
+        }
+    }
+    else if (ssl != NULL && strcEQ(var, "COMPRESS_METHOD")) {
+        result = ssl_var_lookup_ssl_compress_meth(ssl);
+    }
+#ifdef HAVE_TLSEXT
+    else if (ssl != NULL && strcEQ(var, "TLS_SNI")) {
+        result = apr_pstrdup(p, SSL_get_servername(ssl,
+                                                   TLSEXT_NAMETYPE_host_name));
+    }
+#endif
+    else if (ssl != NULL && strcEQ(var, "SECURE_RENEG")) {
+        int flag = 0;
+#ifdef SSL_get_secure_renegotiation_support
+        flag = SSL_get_secure_renegotiation_support(ssl);
+#endif
+        result = apr_pstrdup(p, flag ? "true" : "false");
+    }
+#ifdef HAVE_SRP
+    else if (ssl != NULL && strcEQ(var, "SRP_USER")) {
+        if ((result = SSL_get_srp_username(ssl)) != NULL) {
+            result = apr_pstrdup(p, result);
+        }
+    }
+    else if (ssl != NULL && strcEQ(var, "SRP_USERINFO")) {
+        if ((result = SSL_get_srp_userinfo(ssl)) != NULL) {
+            result = apr_pstrdup(p, result);
+        }
+    }
+#endif
+
+    return result;
+}
+
+static char *ssl_var_lookup_ssl_cert_dn_oneline(apr_pool_t *p, request_rec *r,
+                                                X509_NAME *xsname)
+{
+    char *result = NULL;
+    SSLDirConfigRec *dc;
+    int legacy_format = 0;
+    if (r) {
+        dc = myDirConfig(r);
+        legacy_format = dc->nOptions & SSL_OPT_LEGACYDNFORMAT;
+    }
+    if (legacy_format) {
+        char *cp = X509_NAME_oneline(xsname, NULL, 0);
+        result = apr_pstrdup(p, cp);
+        OPENSSL_free(cp);
+    }
+    else {
+        BIO* bio;
+        int n;
+        unsigned long flags = XN_FLAG_RFC2253 & ~ASN1_STRFLGS_ESC_MSB;
+        if ((bio = BIO_new(BIO_s_mem())) == NULL)
+            return NULL;
+        X509_NAME_print_ex(bio, xsname, 0, flags);
+        n = BIO_pending(bio);
+        if (n > 0) {
+            result = apr_palloc(p, n+1);
+            n = BIO_read(bio, result, n);
+            result[n] = NUL;
+        }
+        BIO_free(bio);
+    }
+    return result;
+}
+
+static char *ssl_var_lookup_ssl_cert(apr_pool_t *p, request_rec *r, X509 *xs,
+                                     char *var)
+{
+    char *result;
+    BOOL resdup;
+    X509_NAME *xsname;
+    int nid;
+
+    result = NULL;
+    resdup = TRUE;
+
+    if (strcEQ(var, "M_VERSION")) {
+        result = apr_psprintf(p, "%lu", X509_get_version(xs)+1);
+        resdup = FALSE;
+    }
+    else if (strcEQ(var, "M_SERIAL")) {
+        result = ssl_var_lookup_ssl_cert_serial(p, xs);
+    }
+    else if (strcEQ(var, "V_START")) {
+        result = ssl_var_lookup_ssl_cert_valid(p, X509_get_notBefore(xs));
+    }
+    else if (strcEQ(var, "V_END")) {
+        result = ssl_var_lookup_ssl_cert_valid(p, X509_get_notAfter(xs));
+    }
+    else if (strcEQ(var, "V_REMAIN")) {
+        result = ssl_var_lookup_ssl_cert_remain(p, X509_get_notAfter(xs));
+        resdup = FALSE;
+    }
+    else if (*var && strcEQ(var+1, "_DN")) {
+        if (*var == 'S')
+            xsname = X509_get_subject_name(xs);
+        else if (*var == 'I')
+            xsname = X509_get_issuer_name(xs);
+        else
+            return NULL;
+        result = ssl_var_lookup_ssl_cert_dn_oneline(p, r, xsname);
+        resdup = FALSE;
+    }
+    else if (strlen(var) > 5 && strcEQn(var+1, "_DN_", 4)) {
+        if (*var == 'S')
+            xsname = X509_get_subject_name(xs);
+        else if (*var == 'I')
+            xsname = X509_get_issuer_name(xs);
+        else
+            return NULL;
+        result = ssl_var_lookup_ssl_cert_dn(p, xsname, var+5);
+        resdup = FALSE;
+    }
+    else if (strlen(var) > 4 && strcEQn(var, "SAN_", 4)) {
+        result = ssl_var_lookup_ssl_cert_san(p, xs, var+4);
+        resdup = FALSE;
+    }
+    else if (strcEQ(var, "A_SIG")) {
+#if MODSSL_USE_OPENSSL_PRE_1_1_API
+        nid = OBJ_obj2nid((ASN1_OBJECT *)(xs->cert_info->signature->algorithm));
+#else
+        const ASN1_OBJECT *paobj;
+        X509_ALGOR_get0(&paobj, NULL, NULL, X509_get0_tbs_sigalg(xs));
+        nid = OBJ_obj2nid(paobj);
+#endif
+        result = apr_pstrdup(p,
+                             (nid == NID_undef) ? "UNKNOWN" : OBJ_nid2ln(nid));
+        resdup = FALSE;
+    }
+    else if (strcEQ(var, "A_KEY")) {
+#if OPENSSL_VERSION_NUMBER < 0x10100000L
+        nid = OBJ_obj2nid((ASN1_OBJECT *)(xs->cert_info->key->algor->algorithm));
+#else
+        ASN1_OBJECT *paobj;
+        X509_PUBKEY_get0_param(&paobj, NULL, 0, NULL, X509_get_X509_PUBKEY(xs));
+        nid = OBJ_obj2nid(paobj);
+#endif
+        result = apr_pstrdup(p,
+                             (nid == NID_undef) ? "UNKNOWN" : OBJ_nid2ln(nid));
+        resdup = FALSE;
+    }
+    else if (strcEQ(var, "CERT")) {
+        result = ssl_var_lookup_ssl_cert_PEM(p, xs);
+    }
+
+    if (resdup)
+        result = apr_pstrdup(p, result);
+    return result;
+}
+
+/* In this table, .extract is non-zero if RDNs using the NID should be
+ * extracted to for the SSL_{CLIENT,SERVER}_{I,S}_DN_* environment
+ * variables. */
+static const struct {
+    char *name;
+    int   nid;
+    int   extract;
+} ssl_var_lookup_ssl_cert_dn_rec[] = {
+    { "C",     NID_countryName,            1 },
+    { "ST",    NID_stateOrProvinceName,    1 }, /* officially    (RFC2156) */
+    { "SP",    NID_stateOrProvinceName,    0 }, /* compatibility (SSLeay)  */
+    { "L",     NID_localityName,           1 },
+    { "O",     NID_organizationName,       1 },
+    { "OU",    NID_organizationalUnitName, 1 },
+    { "CN",    NID_commonName,             1 },
+    { "T",     NID_title,                  1 },
+    { "I",     NID_initials,               1 },
+    { "G",     NID_givenName,              1 },
+    { "S",     NID_surname,                1 },
+    { "D",     NID_description,            1 },
+#ifdef NID_userId
+    { "UID",   NID_userId,                 1 },
+#endif
+    { "Email", NID_pkcs9_emailAddress,     1 },
+    { NULL,    0,                          0 }
+};
+
+static char *ssl_var_lookup_ssl_cert_dn(apr_pool_t *p, X509_NAME *xsname,
+                                        const char *var)
+{
+    const char *ptr;
+    char *result;
+    X509_NAME_ENTRY *xsne;
+    int i, j, n, idx = 0, raw = 0;
+    apr_size_t varlen;
+
+    ptr = ap_strrchr_c(var, '_');
+    if (ptr && ptr > var && strcmp(ptr + 1, "RAW") == 0) {
+        var = apr_pstrmemdup(p, var, ptr - var);
+        raw = 1;
+    }
+    
+    /* if an _N suffix is used, find the Nth attribute of given name */
+    ptr = ap_strchr_c(var, '_');
+    if (ptr != NULL && strspn(ptr + 1, "0123456789") == strlen(ptr + 1)) {
+        idx = atoi(ptr + 1);
+        varlen = ptr - var;
+    } else {
+        varlen = strlen(var);
+    }
+
+    result = NULL;
+
+    for (i = 0; ssl_var_lookup_ssl_cert_dn_rec[i].name != NULL; i++) {
+        if (strEQn(var, ssl_var_lookup_ssl_cert_dn_rec[i].name, varlen)
+            && strlen(ssl_var_lookup_ssl_cert_dn_rec[i].name) == varlen) {
+            for (j = 0; j < X509_NAME_entry_count(xsname); j++) {
+                xsne = X509_NAME_get_entry(xsname, j);
+
+                n =OBJ_obj2nid((ASN1_OBJECT *)X509_NAME_ENTRY_get_object(xsne));
+
+                if (n == ssl_var_lookup_ssl_cert_dn_rec[i].nid && idx-- == 0) {
+                    result = modssl_X509_NAME_ENTRY_to_string(p, xsne, raw);
+                    break;
+                }
+            }
+            break;
+        }
+    }
+    return result;
+}
+
+static char *ssl_var_lookup_ssl_cert_san(apr_pool_t *p, X509 *xs, char *var)
+{
+    int type, numlen;
+    const char *onf = NULL;
+    apr_array_header_t *entries;
+
+    if (strcEQn(var, "Email_", 6)) {
+        type = GEN_EMAIL;
+        var += 6;
+    }
+    else if (strcEQn(var, "DNS_", 4)) {
+        type = GEN_DNS;
+        var += 4;
+    }
+    else if (strcEQn(var, "OTHER_", 6)) {
+        type = GEN_OTHERNAME;
+        var += 6;
+        if (strEQn(var, "msUPN_", 6)) {
+            var += 6;
+            onf = "msUPN";
+        }
+        else if (strEQn(var, "dnsSRV_", 7)) {
+            var += 7;
+            onf = "id-on-dnsSRV";
+        }
+        else
+           return NULL;
+    }
+    else
+        return NULL;
+
+    /* sanity check: number must be between 1 and 4 digits */
+    numlen = strspn(var, "0123456789");
+    if ((numlen < 1) || (numlen > 4) || (numlen != strlen(var)))
+        return NULL;
+
+    if (modssl_X509_getSAN(p, xs, type, onf, atoi(var), &entries))
+        /* return the first entry from this 1-element array */
+        return APR_ARRAY_IDX(entries, 0, char *);
+    else
+        return NULL;
+}
+
+static char *ssl_var_lookup_ssl_cert_valid(apr_pool_t *p, ASN1_TIME *tm)
+{
+    char *result;
+    BIO* bio;
+    int n;
+
+    if ((bio = BIO_new(BIO_s_mem())) == NULL)
+        return NULL;
+    ASN1_TIME_print(bio, tm);
+    n = BIO_pending(bio);
+    result = apr_pcalloc(p, n+1);
+    n = BIO_read(bio, result, n);
+    result[n] = NUL;
+    BIO_free(bio);
+    return result;
+}
+
+#define DIGIT2NUM(x) (((x)[0] - '0') * 10 + (x)[1] - '0')
+
+/* Return a string giving the number of days remaining until 'tm', or
+ * "0" if this can't be determined. */
+static char *ssl_var_lookup_ssl_cert_remain(apr_pool_t *p, ASN1_TIME *tm)
+{
+    apr_time_t then, now = apr_time_now();
+    apr_time_exp_t exp = {0};
+    long diff;
+    unsigned char *dp;
+
+    /* Fail if the time isn't a valid ASN.1 TIME; RFC3280 mandates
+     * that the seconds digits are present even though ASN.1
+     * doesn't. */
+    if ((tm->type == V_ASN1_UTCTIME && tm->length < 11) ||
+        (tm->type == V_ASN1_GENERALIZEDTIME && tm->length < 13) ||
+        !ASN1_TIME_check(tm)) {
+        return apr_pstrdup(p, "0");
+    }
+
+    if (tm->type == V_ASN1_UTCTIME) {
+        exp.tm_year = DIGIT2NUM(tm->data);
+        if (exp.tm_year <= 50) exp.tm_year += 100;
+        dp = tm->data + 2;
+    } else {
+        exp.tm_year = DIGIT2NUM(tm->data) * 100 + DIGIT2NUM(tm->data + 2) - 1900;
+        dp = tm->data + 4;
+    }
+
+    exp.tm_mon = DIGIT2NUM(dp) - 1;
+    exp.tm_mday = DIGIT2NUM(dp + 2) + 1;
+    exp.tm_hour = DIGIT2NUM(dp + 4);
+    exp.tm_min = DIGIT2NUM(dp + 6);
+    exp.tm_sec = DIGIT2NUM(dp + 8);
+
+    if (apr_time_exp_gmt_get(&then, &exp) != APR_SUCCESS) {
+        return apr_pstrdup(p, "0");
+    }
+
+    diff = (long)((apr_time_sec(then) - apr_time_sec(now)) / (60*60*24));
+
+    return diff > 0 ? apr_ltoa(p, diff) : apr_pstrdup(p, "0");
+}
+
+static char *ssl_var_lookup_ssl_cert_serial(apr_pool_t *p, X509 *xs)
+{
+    char *result;
+    BIO *bio;
+    int n;
+
+    if ((bio = BIO_new(BIO_s_mem())) == NULL)
+        return NULL;
+    i2a_ASN1_INTEGER(bio, X509_get_serialNumber(xs));
+    n = BIO_pending(bio);
+    result = apr_pcalloc(p, n+1);
+    n = BIO_read(bio, result, n);
+    result[n] = NUL;
+    BIO_free(bio);
+    return result;
+}
+
+static char *ssl_var_lookup_ssl_cert_chain(apr_pool_t *p, STACK_OF(X509) *sk, char *var)
+{
+    char *result;
+    X509 *xs;
+    int n;
+
+    result = NULL;
+
+    if (strspn(var, "0123456789") == strlen(var)) {
+        n = atoi(var);
+        if (n < sk_X509_num(sk)) {
+            xs = sk_X509_value(sk, n);
+            result = ssl_var_lookup_ssl_cert_PEM(p, xs);
+        }
+    }
+
+    return result;
+}
+
+static char *ssl_var_lookup_ssl_cert_rfc4523_cea(apr_pool_t *p, SSL *ssl)
+{
+    char *result;
+    X509 *xs;
+
+    ASN1_INTEGER *serialNumber;
+
+    if (!(xs = SSL_get_peer_certificate(ssl))) {
+        return NULL;
+    }
+
+    result = NULL;
+
+    serialNumber = X509_get_serialNumber(xs);
+    if (serialNumber) {
+        X509_NAME *issuer = X509_get_issuer_name(xs);
+        if (issuer) {
+            BIGNUM *bn = ASN1_INTEGER_to_BN(serialNumber, NULL);
+            char *decimal = BN_bn2dec(bn);
+            result = apr_pstrcat(p, "{ serialNumber ", decimal,
+                    ", issuer rdnSequence:\"",
+                    modssl_X509_NAME_to_string(p, issuer, 0), "\" }", NULL);
+            OPENSSL_free(decimal);
+            BN_free(bn);
+        }
+    }
+
+    X509_free(xs);
+    return result;
+}
+
+static char *ssl_var_lookup_ssl_cert_PEM(apr_pool_t *p, X509 *xs)
+{
+    char *result;
+    BIO *bio;
+    int n;
+
+    if ((bio = BIO_new(BIO_s_mem())) == NULL)
+        return NULL;
+    PEM_write_bio_X509(bio, xs);
+    n = BIO_pending(bio);
+    result = apr_pcalloc(p, n+1);
+    n = BIO_read(bio, result, n);
+    result[n] = NUL;
+    BIO_free(bio);
+    return result;
+}
+
+static char *ssl_var_lookup_ssl_cert_verify(apr_pool_t *p, SSLConnRec *sslconn)
+{
+    char *result;
+    long vrc;
+    const char *verr;
+    const char *vinfo;
+    SSL *ssl;
+    X509 *xs;
+
+    result = NULL;
+    ssl   = sslconn->ssl;
+    verr  = sslconn->verify_error;
+    vinfo = sslconn->verify_info;
+    vrc   = SSL_get_verify_result(ssl);
+    xs    = SSL_get_peer_certificate(ssl);
+
+    if (vrc == X509_V_OK && verr == NULL && xs == NULL)
+        /* no client verification done at all */
+        result = "NONE";
+    else if (vrc == X509_V_OK && verr == NULL && vinfo == NULL && xs != NULL)
+        /* client verification done successful */
+        result = "SUCCESS";
+    else if (vrc == X509_V_OK && vinfo != NULL && strEQ(vinfo, "GENEROUS"))
+        /* client verification done in generous way */
+        result = "GENEROUS";
+    else
+        /* client verification failed */
+        result = apr_psprintf(p, "FAILED:%s",
+                              verr ? verr : X509_verify_cert_error_string(vrc));
+
+    if (xs)
+        X509_free(xs);
+    return result;
+}
+
+static char *ssl_var_lookup_ssl_cipher(apr_pool_t *p, SSLConnRec *sslconn, char *var)
+{
+    char *result;
+    BOOL resdup;
+    int usekeysize, algkeysize;
+    SSL *ssl;
+
+    result = NULL;
+    resdup = TRUE;
+
+    ssl = sslconn->ssl;
+    ssl_var_lookup_ssl_cipher_bits(ssl, &usekeysize, &algkeysize);
+
+    if (ssl && strEQ(var, "")) {
+        MODSSL_SSL_CIPHER_CONST SSL_CIPHER *cipher = SSL_get_current_cipher(ssl);
+        result = (cipher != NULL ? (char *)SSL_CIPHER_get_name(cipher) : NULL);
+    }
+    else if (strcEQ(var, "_EXPORT"))
+        result = (usekeysize < 56 ? "true" : "false");
+    else if (strcEQ(var, "_USEKEYSIZE")) {
+        result = apr_itoa(p, usekeysize);
+        resdup = FALSE;
+    }
+    else if (strcEQ(var, "_ALGKEYSIZE")) {
+        result = apr_itoa(p, algkeysize);
+        resdup = FALSE;
+    }
+
+    if (result != NULL && resdup)
+        result = apr_pstrdup(p, result);
+    return result;
+}
+
+static void ssl_var_lookup_ssl_cipher_bits(SSL *ssl, int *usekeysize, int *algkeysize)
+{
+    MODSSL_SSL_CIPHER_CONST SSL_CIPHER *cipher;
+
+    *usekeysize = 0;
+    *algkeysize = 0;
+    if (ssl != NULL)
+        if ((cipher = SSL_get_current_cipher(ssl)) != NULL)
+            *usekeysize = SSL_CIPHER_get_bits(cipher, algkeysize);
+    return;
+}
+
+static char *ssl_var_lookup_ssl_version(apr_pool_t *p, char *var)
+{
+    if (strEQ(var, "INTERFACE")) {
+        return apr_pstrdup(p, var_interface);
+    }
+    else if (strEQ(var, "LIBRARY_INTERFACE")) {
+        return apr_pstrdup(p, var_library_interface);
+    }
+    else if (strEQ(var, "LIBRARY")) {
+        return apr_pstrdup(p, var_library);
+    }
+    return NULL;
+}
+
+/* Add each RDN in 'xn' to the table 't' where the NID is present in
+ * 'nids', using key prefix 'pfx'.  */
+static void extract_dn(apr_table_t *t, apr_hash_t *nids, const char *pfx,
+                       X509_NAME *xn, apr_pool_t *p)
+{
+    X509_NAME_ENTRY *xsne;
+    apr_hash_t *count;
+    int i, nid;
+
+    /* Hash of (int) NID -> (int *) counter to count each time an RDN
+     * with the given NID has been seen. */
+    count = apr_hash_make(p);
+
+    /* For each RDN... */
+    for (i = 0; i < X509_NAME_entry_count(xn); i++) {
+         const char *tag;
+         xsne = X509_NAME_get_entry(xn, i);
+
+         /* Retrieve the nid, and check whether this is one of the nids
+          * which are to be extracted. */
+         nid = OBJ_obj2nid((ASN1_OBJECT *)X509_NAME_ENTRY_get_object(xsne));
+
+         tag = apr_hash_get(nids, &nid, sizeof nid);
+         if (tag) {
+             const char *key;
+             int *dup;
+             char *value;
+
+             /* Check whether a variable with this nid was already
+              * been used; if so, use the foo_N=bar syntax. */
+             dup = apr_hash_get(count, &nid, sizeof nid);
+             if (dup) {
+                 key = apr_psprintf(p, "%s%s_%d", pfx, tag, ++(*dup));
+             }
+             else {
+                 /* Otherwise, use the plain foo=bar syntax. */
+                 dup = apr_pcalloc(p, sizeof *dup);
+                 apr_hash_set(count, &nid, sizeof nid, dup);
+                 key = apr_pstrcat(p, pfx, tag, NULL);
+             }
+             value = modssl_X509_NAME_ENTRY_to_string(p, xsne, 0);
+             apr_table_setn(t, key, value);
+         }
+    }
+}
+
+void modssl_var_extract_dns(apr_table_t *t, SSL *ssl, apr_pool_t *p)
+{
+    apr_hash_t *nids;
+    unsigned n;
+    X509 *xs;
+
+    /* Build up a hash table of (int *)NID->(char *)short-name for all
+     * the tags which are to be extracted: */
+    nids = apr_hash_make(p);
+    for (n = 0; ssl_var_lookup_ssl_cert_dn_rec[n].name; n++) {
+        if (ssl_var_lookup_ssl_cert_dn_rec[n].extract) {
+            apr_hash_set(nids, &ssl_var_lookup_ssl_cert_dn_rec[n].nid,
+                         sizeof(ssl_var_lookup_ssl_cert_dn_rec[0].nid),
+                         ssl_var_lookup_ssl_cert_dn_rec[n].name);
+        }
+    }
+
+    /* Extract the server cert DNS -- note that the refcount does NOT
+     * increase: */
+    xs = SSL_get_certificate(ssl);
+    if (xs) {
+        extract_dn(t, nids, "SSL_SERVER_S_DN_", X509_get_subject_name(xs), p);
+        extract_dn(t, nids, "SSL_SERVER_I_DN_", X509_get_issuer_name(xs), p);
+    }
+
+    /* Extract the client cert DNs -- note that the refcount DOES
+     * increase: */
+    xs = SSL_get_peer_certificate(ssl);
+    if (xs) {
+        extract_dn(t, nids, "SSL_CLIENT_S_DN_", X509_get_subject_name(xs), p);
+        extract_dn(t, nids, "SSL_CLIENT_I_DN_", X509_get_issuer_name(xs), p);
+        X509_free(xs);
+    }
+}
+
+static void extract_san_array(apr_table_t *t, const char *pfx,
+                              apr_array_header_t *entries, apr_pool_t *p)
+{
+    int i;
+
+    for (i = 0; i < entries->nelts; i++) {
+        const char *key = apr_psprintf(p, "%s_%d", pfx, i);
+        apr_table_setn(t, key, APR_ARRAY_IDX(entries, i, const char *));
+    }
+}
+
+void modssl_var_extract_san_entries(apr_table_t *t, SSL *ssl, apr_pool_t *p)
+{
+    X509 *xs;
+    apr_array_header_t *entries;
+
+    /* subjectAltName entries of the server certificate */
+    xs = SSL_get_certificate(ssl);
+    if (xs) {
+        if (modssl_X509_getSAN(p, xs, GEN_EMAIL, NULL, -1, &entries)) {
+            extract_san_array(t, "SSL_SERVER_SAN_Email", entries, p);
+        }
+        if (modssl_X509_getSAN(p, xs, GEN_DNS, NULL, -1, &entries)) {
+            extract_san_array(t, "SSL_SERVER_SAN_DNS", entries, p);
+        }
+        if (modssl_X509_getSAN(p, xs, GEN_OTHERNAME, "id-on-dnsSRV", -1,
+                               &entries)) {
+            extract_san_array(t, "SSL_SERVER_SAN_OTHER_dnsSRV", entries, p);
+        }
+        /* no need to free xs (refcount does not increase) */
+    }
+
+    /* subjectAltName entries of the client certificate */
+    xs = SSL_get_peer_certificate(ssl);
+    if (xs) {
+        if (modssl_X509_getSAN(p, xs, GEN_EMAIL, NULL, -1, &entries)) {
+            extract_san_array(t, "SSL_CLIENT_SAN_Email", entries, p);
+        }
+        if (modssl_X509_getSAN(p, xs, GEN_DNS, NULL, -1, &entries)) {
+            extract_san_array(t, "SSL_CLIENT_SAN_DNS", entries, p);
+        }
+        if (modssl_X509_getSAN(p, xs, GEN_OTHERNAME, "msUPN", -1, &entries)) {
+            extract_san_array(t, "SSL_CLIENT_SAN_OTHER_msUPN", entries, p);
+        }
+        X509_free(xs);
+    }
+}
+
+/* For an extension type which OpenSSL does not recognize, attempt to
+ * parse the extension type as a primitive string.  This will fail for
+ * any structured extension type per the docs.  Returns non-zero on
+ * success and writes the string to the given bio. */
+static int dump_extn_value(BIO *bio, ASN1_OCTET_STRING *str)
+{
+    const unsigned char *pp = str->data;
+    ASN1_STRING *ret = ASN1_STRING_new();
+    int rv = 0;
+
+    /* This allows UTF8String, IA5String, VisibleString, or BMPString;
+     * conversion to UTF-8 is forced. */
+    if (d2i_DISPLAYTEXT(&ret, &pp, str->length)) {
+        ASN1_STRING_print_ex(bio, ret, ASN1_STRFLGS_UTF8_CONVERT);
+        rv = 1;
+    }
+
+    ASN1_STRING_free(ret);
+    return rv;
+}
+
+apr_array_header_t *ssl_ext_list(apr_pool_t *p, conn_rec *c, int peer,
+                                 const char *extension)
+{
+    SSLConnRec *sslconn = ssl_get_effective_config(c);
+    SSL *ssl = NULL;
+    apr_array_header_t *array = NULL;
+    X509 *xs = NULL;
+    ASN1_OBJECT *oid = NULL;
+    int count = 0, j;
+
+    if (!sslconn || !sslconn->ssl || !extension) {
+        return NULL;
+    }
+    ssl = sslconn->ssl;
+
+    /* We accept the "extension" string to be converted as
+     * a long name (nsComment), short name (DN) or
+     * numeric OID (1.2.3.4).
+     */
+    oid = OBJ_txt2obj(extension, 0);
+    if (!oid) {
+        ap_log_cerror(APLOG_MARK, APLOG_DEBUG, 0, c, APLOGNO(01970)
+                      "could not parse OID '%s'", extension);
+        ERR_clear_error();
+        return NULL;
+    }
+
+    xs = peer ? SSL_get_peer_certificate(ssl) : SSL_get_certificate(ssl);
+    if (xs == NULL) {
+        return NULL;
+    }
+
+    count = X509_get_ext_count(xs);
+    /* Create an array large enough to accommodate every extension. This is
+     * likely overkill, but safe.
+     */
+    array = apr_array_make(p, count, sizeof(char *));
+    for (j = 0; j < count; j++) {
+        X509_EXTENSION *ext = X509_get_ext(xs, j);
+
+        if (OBJ_cmp(X509_EXTENSION_get_object(ext), oid) == 0) {
+            BIO *bio = BIO_new(BIO_s_mem());
+
+            /* We want to obtain a string representation of the extensions
+             * value and add it to the array we're building.
+             * X509V3_EXT_print() doesn't know about all the possible
+             * data types, but the value is stored as an ASN1_OCTET_STRING
+             * allowing us a fallback in case of X509V3_EXT_print
+             * not knowing how to handle the data.
+             */
+            if (X509V3_EXT_print(bio, ext, 0, 0) == 1 ||
+                dump_extn_value(bio, X509_EXTENSION_get_data(ext)) == 1) {
+                BUF_MEM *buf;
+                char **ptr = apr_array_push(array);
+                BIO_get_mem_ptr(bio, &buf);
+                *ptr = apr_pstrmemdup(p, buf->data, buf->length);
+            } else {
+                ap_log_cerror(APLOG_MARK, APLOG_DEBUG, 0, c, APLOGNO(01971)
+                              "Found an extension '%s', but failed to "
+                              "create a string from it", extension);
+            }
+            BIO_vfree(bio);
+        }
+    }
+
+    if (array->nelts == 0)
+        array = NULL;
+
+    if (peer) {
+        /* only SSL_get_peer_certificate raises the refcount */
+        X509_free(xs);
+    }
+
+    ASN1_OBJECT_free(oid);
+    ERR_clear_error();
+    return array;
+}
+
+static char *ssl_var_lookup_ssl_compress_meth(SSL *ssl)
+{
+    char *result = "NULL";
+#ifndef OPENSSL_NO_COMP
+    SSL_SESSION *pSession = SSL_get_session(ssl);
+
+    if (pSession) {
+#ifdef OPENSSL_NO_SSL_INTERN
+        switch (SSL_SESSION_get_compress_id(pSession)) {
+#else
+        switch (pSession->compress_meth) {
+#endif
+        case 0:
+            /* default "NULL" already set */
+            break;
+
+            /* Defined by RFC 3749, deflate is coded by "1" */
+        case 1:
+            result = "DEFLATE";
+            break;
+
+            /* IANA assigned compression number for LZS */
+        case 0x40:
+            result = "LZS";
+            break;
+
+        default:
+            result = "UNKNOWN";
+            break;
+        }
+    }
+#endif
+    return result;
+}
+
+/*  _________________________________________________________________
+**
+**  SSL Extension to mod_log_config
+**  _________________________________________________________________
+*/
+
+#include "../../modules/loggers/mod_log_config.h"
+
+static const char *ssl_var_log_handler_c(request_rec *r, char *a);
+static const char *ssl_var_log_handler_x(request_rec *r, char *a);
+
+/*
+ * register us for the mod_log_config function registering phase
+ * to establish %{...}c and to be able to expand %{...}x variables.
+ */
+void ssl_var_log_config_register(apr_pool_t *p)
+{
+    APR_OPTIONAL_FN_TYPE(ap_register_log_handler) *log_pfn_register;
+
+    log_pfn_register = APR_RETRIEVE_OPTIONAL_FN(ap_register_log_handler);
+
+    if (log_pfn_register) {
+        log_pfn_register(p, "c", ssl_var_log_handler_c, 0);
+        log_pfn_register(p, "x", ssl_var_log_handler_x, 0);
+    }
+    return;
+}
+
+/*
+ * implement the %{..}c log function
+ * (we are the only function)
+ */
+static const char *ssl_var_log_handler_c(request_rec *r, char *a)
+{
+    SSLConnRec *sslconn = ssl_get_effective_config(r->connection);
+    char *result;
+
+    if (sslconn == NULL || sslconn->ssl == NULL)
+        return NULL;
+    result = NULL;
+    if (strEQ(a, "version"))
+        result = ssl_var_lookup(r->pool, r->server, r->connection, r, "SSL_PROTOCOL");
+    else if (strEQ(a, "cipher"))
+        result = ssl_var_lookup(r->pool, r->server, r->connection, r, "SSL_CIPHER");
+    else if (strEQ(a, "subjectdn") || strEQ(a, "clientcert"))
+        result = ssl_var_lookup(r->pool, r->server, r->connection, r, "SSL_CLIENT_S_DN");
+    else if (strEQ(a, "issuerdn") || strEQ(a, "cacert"))
+        result = ssl_var_lookup(r->pool, r->server, r->connection, r, "SSL_CLIENT_I_DN");
+    else if (strEQ(a, "errcode"))
+        result = "-";
+    else if (strEQ(a, "errstr"))
+        result = (char *)sslconn->verify_error;
+    if (result != NULL && result[0] == NUL)
+        result = NULL;
+    return result;
+}
+
+/*
+ * extend the implementation of the %{..}x log function
+ * (there can be more functions)
+ */
+static const char *ssl_var_log_handler_x(request_rec *r, char *a)
+{
+    char *result;
+
+    result = ssl_var_lookup(r->pool, r->server, r->connection, r, a);
+    if (result != NULL && result[0] == NUL)
+        result = NULL;
+    return result;
+}
+
+