mod_ssl: check request-server for TLS settings compatible to handshake server, allow request if equal, renegotiation checks: remember last used cipher_suite for optimizations, deny any regnegotiation in presence of master connection

git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@1709995 13f79535-47bb-0310-9956-ffa450edef68

modules/ssl/mod_ssl.c

@@ -396,6 +396,7 @@ static int ssl_hook_pre_config(apr_pool_t *pconf,
 static SSLConnRec *ssl_init_connection_ctx(conn_rec *c)
 {
     SSLConnRec *sslconn = myConnConfig(c);
+    SSLSrvConfigRec *sc;
 
     if (sslconn) {
         return sslconn;
@@ -405,6 +406,8 @@ static SSLConnRec *ssl_init_connection_ctx(conn_rec *c)
 
     sslconn->server = c->base_server;
     sslconn->verify_depth = UNSET;
+    sc = mySrvConfig(c->base_server);
+    sslconn->cipher_suite = sc->server->auth.cipher_suite;
 
     myConnConfigSet(c, sslconn);
 
@@ -563,7 +566,7 @@ static int ssl_hook_pre_connection(conn_rec *c, void *csd)
     /*
      * Immediately stop processing if SSL is disabled for this connection
      */
-    if (!(sc && (sc->enabled == SSL_ENABLED_TRUE ||
+    if (c->master || !(sc && (sc->enabled == SSL_ENABLED_TRUE ||
                               (sslconn && sslconn->is_proxy))))
     {
         return DECLINED;

modules/ssl/ssl_engine_kernel.c

@@ -113,6 +113,108 @@ static int has_buffered_data(request_rec *r)
     return result;
 }
 
+static int ap_array_same_str_set(apr_array_header_t *s1, apr_array_header_t *s2)
+{
+    int i;
+    const char *c;
+    
+    if (s1 == s2) {
+        return 1;
+    }
+    else if (!s1 || !s2 || (s1->nelts != s2->nelts)) {
+        return 0;
+    }
+    
+    for (i = 0; i < s1->nelts; i++) {
+        c = APR_ARRAY_IDX(s1, i, const char *);
+        if (!c || !ap_array_str_contains(s2, c)) {
+            return 0;
+        }
+    }
+    return 1;
+}
+
+static int ssl_pk_server_compatible(modssl_pk_server_t *pks1, 
+                                    modssl_pk_server_t *pks2) 
+{
+    if (!pks1 || !pks2) {
+        return 0;
+    }
+    /* both have the same certificates? */
+    if ((pks1->ca_name_path != pks2->ca_name_path)
+        && (!pks1->ca_name_path || !pks2->ca_name_path 
+            || strcmp(pks1->ca_name_path, pks2->ca_name_path))) {
+        return 0;
+    }
+    if ((pks1->ca_name_file != pks2->ca_name_file)
+        && (!pks1->ca_name_file || !pks2->ca_name_file 
+            || strcmp(pks1->ca_name_file, pks2->ca_name_file))) {
+        return 0;
+    }
+    if (!ap_array_same_str_set(pks1->cert_files, pks2->cert_files)
+        || !ap_array_same_str_set(pks1->key_files, pks2->key_files)) {
+        return 0;
+    }
+    return 1;
+}
+
+static int ssl_auth_compatible(modssl_auth_ctx_t *a1, 
+                               modssl_auth_ctx_t *a2) 
+{
+    if (!a1 || !a2) {
+        return 0;
+    }
+    /* both have the same verification */
+    if ((a1->verify_depth != a2->verify_depth)
+        || (a1->verify_mode != a2->verify_mode)) {
+        return 0;
+    }
+    /* both have the same ca path/file */
+    if ((a1->ca_cert_path != a2->ca_cert_path)
+        && (!a1->ca_cert_path || !a2->ca_cert_path 
+            || strcmp(a1->ca_cert_path, a2->ca_cert_path))) {
+        return 0;
+    }
+    if ((a1->ca_cert_file != a2->ca_cert_file)
+        && (!a1->ca_cert_file || !a2->ca_cert_file 
+            || strcmp(a1->ca_cert_file, a2->ca_cert_file))) {
+        return 0;
+    }
+    /* both have the same ca cipher suite string */
+    if ((a1->cipher_suite != a2->cipher_suite)
+        && (!a1->cipher_suite || !a2->cipher_suite 
+            || strcmp(a1->cipher_suite, a2->cipher_suite))) {
+        return 0;
+    }
+    return 1;
+}
+
+static int ssl_ctx_compatible(modssl_ctx_t *ctx1, 
+                              modssl_ctx_t *ctx2) 
+{
+    if (!ctx1 || !ctx2 
+        || (ctx1->protocol != ctx2->protocol)
+        || !ssl_auth_compatible(&ctx1->auth, &ctx2->auth)
+        || !ssl_pk_server_compatible(ctx1->pks, ctx2->pks)) {
+        return 0;
+    }
+    return 1;
+}
+
+static int ssl_server_compatible(server_rec *s1, server_rec *s2)
+{
+    SSLSrvConfigRec *sc1 = s1? mySrvConfig(s1) : NULL;
+    SSLSrvConfigRec *sc2 = s2? mySrvConfig(s2) : NULL;
+
+    /* both use the same TLS protocol? */
+    if (!sc1 || !sc2 
+        || !ssl_ctx_compatible(sc1->server, sc2->server)) {
+        return 0;
+    }
+    
+    return 1;
+}
+
 /*
  *  Post Read Request Handler
  */
@@ -137,7 +239,13 @@ int ssl_hook_ReadReq(request_rec *r)
         }
     }
 
+    /* If we are on a slave connection, we do not expect to have an SSLConnRec,
+     * but our master connection might. */
     sslconn = myConnConfig(r->connection);
+    if (!(sslconn && sslconn->ssl) && r->connection->master) {
+        sslconn = myConnConfig(r->connection->master);
+    }
+    
     if (!sslconn) {
         return DECLINED;
     }
@@ -195,15 +303,16 @@ int ssl_hook_ReadReq(request_rec *r)
                             " provided in HTTP request", servername);
                 return HTTP_BAD_REQUEST;
             }
-            if (r->server != handshakeserver) {
+            if (r->server != handshakeserver 
+                && !ssl_server_compatible(sslconn->server, r->server)) {
                 /* 
-                 * We are really not in Kansas anymore...
                  * The request does not select the virtual host that was
-                 * selected by the SNI.
+                 * selected by the SNI and its SSL parameters are different
                  */
+                
                 ap_log_error(APLOG_MARK, APLOG_ERR, 0, r->server, APLOGNO(02032)
                              "Hostname %s provided via SNI and hostname %s provided"
-                             " via HTTP select a different server",
+                             " via HTTP have no compatible SSL setup",
                              servername, r->hostname);
                 return HTTP_MISDIRECTED_REQUEST;
             }
@@ -302,6 +411,7 @@ int ssl_hook_Access(request_rec *r)
     SSLConnRec *sslconn         = myConnConfig(r->connection);
     SSL *ssl                    = sslconn ? sslconn->ssl : NULL;
     server_rec *handshakeserver = sslconn ? sslconn->server : NULL;
+    SSLSrvConfigRec *hssc       = handshakeserver? mySrvConfig(handshakeserver) : NULL;
     SSL_CTX *ctx = NULL;
     apr_array_header_t *requires;
     ssl_require_t *ssl_requires;
@@ -313,7 +423,18 @@ int ssl_hook_Access(request_rec *r)
     X509_STORE_CTX cert_store_ctx;
     STACK_OF(SSL_CIPHER) *cipher_list_old = NULL, *cipher_list = NULL;
     const SSL_CIPHER *cipher = NULL;
-    int depth, verify_old, verify, n;
+    int depth, verify_old, verify, n, is_slave = 0;
+    const char *ncipher_suite;
+
+    /* On a slave connection, we do not expect to have an SSLConnRec, but
+     * our master connection might have one. */
+    if (!(sslconn && ssl) && r->connection->master) {
+        sslconn         = myConnConfig(r->connection->master);
+        ssl             = sslconn ? sslconn->ssl : NULL;
+        handshakeserver = sslconn ? sslconn->server : NULL;
+        hssc            = handshakeserver? mySrvConfig(handshakeserver) : NULL;
+        is_slave        = 1;
+    }
     
     if (ssl) {
         /*
@@ -333,7 +454,7 @@ int ssl_hook_Access(request_rec *r)
      * Support for SSLRequireSSL directive
      */
     if (dc->bSSLRequired && !ssl) {
-        if (sc->enabled == SSL_ENABLED_OPTIONAL) {
+        if ((sc->enabled == SSL_ENABLED_OPTIONAL) && !is_slave) {
             /* This vhost was configured for optional SSL, just tell the
              * client that we need to upgrade.
              */
@@ -417,7 +538,12 @@ int ssl_hook_Access(request_rec *r)
      *   has to enable this via ``SSLOptions +OptRenegotiate''. So we do no
      *   implicit optimizations.
      */     
-    if (dc->szCipherSuite || (r->server != handshakeserver)) {
+    ncipher_suite = (dc->szCipherSuite? 
+                     dc->szCipherSuite : (r->server != handshakeserver)?
+                     sc->server->auth.cipher_suite : NULL);
+    
+    if (ncipher_suite && (!sslconn->cipher_suite 
+                          || strcmp(ncipher_suite, sslconn->cipher_suite))) {
         /* remember old state */
 
         if (dc->nOptions & SSL_OPT_OPTRENEGOTIATE) {
@@ -432,10 +558,18 @@ int ssl_hook_Access(request_rec *r)
         }
 
         /* configure new state */
-        if ((dc->szCipherSuite || sc->server->auth.cipher_suite) &&
+        if (is_slave) {
-            !SSL_set_cipher_list(ssl, dc->szCipherSuite ?
+            /* TODO: this categorically fails changed cipher suite settings
-                                      dc->szCipherSuite :
+             * on slave connections. We could do better by
-                                      sc->server->auth.cipher_suite)) {
+             * - create a new SSL* from our SSL_CTX and set cipher suite there,
+             *   and retrieve ciphers, free afterwards
+             * Modifying the SSL on a slave connection is no good.
+             */
+            apr_table_setn(r->notes, "ssl-renegotiate-forbidden", "cipher-suite");
+            return HTTP_FORBIDDEN;
+        }
+
+        if (!SSL_set_cipher_list(ssl, ncipher_suite)) {
             ap_log_rerror(APLOG_MARK, APLOG_WARNING, 0, r, APLOGNO(02253)
                           "Unable to reconfigure (per-directory) "
                           "permitted SSL ciphers");
@@ -502,6 +636,15 @@ int ssl_hook_Access(request_rec *r)
         }
 
         if (renegotiate) {
+            if (is_slave) {
+                /* The request causes renegotiation on a slave connection.
+                 * This is not allowed since we might have concurrent requests
+                 * on this connection.
+                 */
+                apr_table_setn(r->notes, "ssl-renegotiate-forbidden", "cipher-suite");
+                return HTTP_FORBIDDEN;
+            }
+            
 #ifdef SSL_OP_CIPHER_SERVER_PREFERENCE
             if (sc->cipher_server_pref == TRUE) {
                 SSL_set_options(ssl, SSL_OP_CIPHER_SERVER_PREFERENCE);
@@ -529,7 +672,6 @@ int ssl_hook_Access(request_rec *r)
      */
     if ((dc->nVerifyClient != SSL_CVERIFY_UNSET) ||
         (sc->server->auth.verify_mode != SSL_CVERIFY_UNSET)) {
-        SSLSrvConfigRec *hssc = mySrvConfig(handshakeserver);
 
         /* remember old state */
         verify_old = SSL_get_verify_mode(ssl);
@@ -549,6 +691,9 @@ int ssl_hook_Access(request_rec *r)
             verify |= SSL_VERIFY_PEER;
         }
 
+        /* TODO: this seems premature since we do not know if there
+         *       are any changes required.
+         */
         SSL_set_verify(ssl, verify, ssl_callback_SSLVerify);
         SSL_set_verify_result(ssl, X509_V_OK);
 
@@ -564,6 +709,14 @@ int ssl_hook_Access(request_rec *r)
                   (verify     & SSL_VERIFY_FAIL_IF_NO_PEER_CERT)))
             {
                 renegotiate = TRUE;
+                if (is_slave) {
+                    /* The request causes renegotiation on a slave connection.
+                     * This is not allowed since we might have concurrent requests
+                     * on this connection.
+                     */
+                    apr_table_setn(r->notes, "ssl-renegotiate-forbidden", "verify-client");
+                    return HTTP_FORBIDDEN;
+                }
                 /* optimization */
 
                 if ((dc->nOptions & SSL_OPT_OPTRENEGOTIATE) &&
@@ -911,6 +1064,10 @@ int ssl_hook_Access(request_rec *r)
                 return HTTP_FORBIDDEN;
             }
         }
+        /* remember any new cipher suite used in renegotiation */
+        if (ncipher_suite) {
+            sslconn->cipher_suite = ncipher_suite;
+        }
     }
 
     /* If we're trying to have the user name set from a client
@@ -1186,6 +1343,10 @@ int ssl_hook_Fixup(request_rec *r)
         apr_table_mergen(r->headers_out, "Connection", "upgrade");
     }
 
+    if (!(sslconn && sslconn->ssl) && r->connection->master) {
+        sslconn = myConnConfig(r->connection->master);
+    }
+
     /*
      * Check to see if SSL is on
      */
@@ -1208,8 +1369,8 @@ int ssl_hook_Fixup(request_rec *r)
 
     /* standard SSL environment variables */
     if (dc->nOptions & SSL_OPT_STDENVVARS) {
-        modssl_var_extract_dns(env, sslconn->ssl, r->pool);
+        modssl_var_extract_dns(env, ssl, r->pool);
-        modssl_var_extract_san_entries(env, sslconn->ssl, r->pool);
+        modssl_var_extract_san_entries(env, ssl, r->pool);
 
         for (i = 0; ssl_hook_Fixup_vars[i]; i++) {
             var = (char *)ssl_hook_Fixup_vars[i];
@@ -2053,6 +2214,7 @@ static int ssl_find_vhost(void *servername, conn_rec *c, server_rec *s)
          * retrieval
          */
         sslcon->server = s;
+        sslcon->cipher_suite = sc->server->auth.cipher_suite;
         
         /*
          * There is one special filter callback, which is set

modules/ssl/ssl_engine_vars.c

@@ -39,7 +39,7 @@
 **  _________________________________________________________________
 */
 
-static char *ssl_var_lookup_ssl(apr_pool_t *p, conn_rec *c, request_rec *r, char *var);
+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, char *var);
 static char *ssl_var_lookup_ssl_cert_san(apr_pool_t *p, X509 *xs, char *var);
@@ -49,8 +49,8 @@ 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, conn_rec *c);
+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, conn_rec *c, char *var);
+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);
@@ -146,7 +146,7 @@ static const char *expr_var_fn(ap_expr_eval_ctx_t *ctx, const void *data)
     char *var = (char *)data;
     SSLConnRec *sslconn = myConnConfig(ctx->c);
 
-    return sslconn ? ssl_var_lookup_ssl(ctx->p, ctx->c, ctx->r, var) : NULL;
+    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,
@@ -332,9 +332,13 @@ char *ssl_var_lookup(apr_pool_t *p, server_rec *s, conn_rec *c, request_rec *r,
      */
     if (result == NULL && c != NULL) {
         SSLConnRec *sslconn = myConnConfig(c);
+        if (!(sslconn && sslconn->ssl) && c->master) {
+            /* use master connection if no SSL defined here */
+            sslconn = myConnConfig(c->master);
+        }
         if (strlen(var) > 4 && strcEQn(var, "SSL_", 4)
             && sslconn && sslconn->ssl)
-            result = ssl_var_lookup_ssl(p, c, r, var+4);
+            result = ssl_var_lookup_ssl(p, sslconn, r, var+4);
         else if (strcEQ(var, "HTTPS")) {
             if (sslconn && sslconn->ssl)
                 result = "on";
@@ -404,10 +408,9 @@ char *ssl_var_lookup(apr_pool_t *p, server_rec *s, conn_rec *c, request_rec *r,
     return (char *)result;
 }
 
-static char *ssl_var_lookup_ssl(apr_pool_t *p, conn_rec *c, request_rec *r,
+static char *ssl_var_lookup_ssl(apr_pool_t *p, SSLConnRec *sslconn, 
-                                char *var)
+                                request_rec *r, char *var)
 {
-    SSLConnRec *sslconn = myConnConfig(c);
     char *result;
     X509 *xs;
     STACK_OF(X509) *sk;
@@ -447,7 +450,7 @@ static char *ssl_var_lookup_ssl(apr_pool_t *p, conn_rec *c, request_rec *r,
             result = "Initial";
     }
     else if (ssl != NULL && strlen(var) >= 6 && strcEQn(var, "CIPHER", 6)) {
-        result = ssl_var_lookup_ssl_cipher(p, c, var+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);
@@ -457,7 +460,7 @@ static char *ssl_var_lookup_ssl(apr_pool_t *p, conn_rec *c, request_rec *r,
         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, c);
+        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) {
@@ -866,9 +869,8 @@ static char *ssl_var_lookup_ssl_cert_PEM(apr_pool_t *p, X509 *xs)
     return result;
 }
 
-static char *ssl_var_lookup_ssl_cert_verify(apr_pool_t *p, conn_rec *c)
+static char *ssl_var_lookup_ssl_cert_verify(apr_pool_t *p, SSLConnRec *sslconn)
 {
-    SSLConnRec *sslconn = myConnConfig(c);
     char *result;
     long vrc;
     const char *verr;
@@ -902,9 +904,8 @@ static char *ssl_var_lookup_ssl_cert_verify(apr_pool_t *p, conn_rec *c)
     return result;
 }
 
-static char *ssl_var_lookup_ssl_cipher(apr_pool_t *p, conn_rec *c, char *var)
+static char *ssl_var_lookup_ssl_cipher(apr_pool_t *p, SSLConnRec *sslconn, char *var)
 {
-    SSLConnRec *sslconn = myConnConfig(c);
     char *result;
     BOOL resdup;
     int usekeysize, algkeysize;

modules/ssl/ssl_private.h

@@ -450,6 +450,8 @@ typedef struct {
     } reneg_state;
 
     server_rec *server;
+    
+    const char *cipher_suite; /* cipher suite used in last reneg */
 } SSLConnRec;
 
 /* BIG FAT WARNING: SSLModConfigRec has unusual memory lifetime: it is