Version bump - v1.17.7

.hgtags

@@ -444,3 +444,4 @@ d2fd76709909767fc727a5b4affcf1dc9ca488a7 release-1.15.9
 ed4303aa1b31a9aad5440640c0840d9d0af45fed release-1.17.3
 ce2ced3856909f36f8130c99eaa4dbdbae636ddc release-1.17.4
 9af0dddbddb2c368bfedd2801bc100ffad01e19b release-1.17.5
+de68d0d94320cbf033599c6f3ca37e5335c67fd7 release-1.17.6

docs/xml/nginx/changes.xml

@@ -5,6 +5,38 @@
 <change_log title="nginx">
 
 
+<changes ver="1.17.6" date="2019-11-19">
+
+<change type="feature">
+<para lang="ru">
+переменные $proxy_protocol_server_addr и $proxy_protocol_server_port.
+</para>
+<para lang="en">
+the $proxy_protocol_server_addr and $proxy_protocol_server_port variables.
+</para>
+</change>
+
+<change type="feature">
+<para lang="ru">
+директива limit_conn_dry_run.
+</para>
+<para lang="en">
+the "limit_conn_dry_run" directive.
+</para>
+</change>
+
+<change type="feature">
+<para lang="ru">
+переменные $limit_req_status и $limit_conn_status.
+</para>
+<para lang="en">
+the $limit_req_status and $limit_conn_status variables.
+</para>
+</change>
+
+</changes>
+
+
 <changes ver="1.17.5" date="2019-10-22">
 
 <change type="feature">

src/core/nginx.h

@@ -9,8 +9,8 @@
 #define _NGINX_H_INCLUDED_
 
 
-#define nginx_version      1017006
+#define nginx_version      1017007
-#define NGINX_VERSION      "1.17.6"
+#define NGINX_VERSION      "1.17.7"
 #define NGINX_VER          "nginx/" NGINX_VERSION " by Hakase"
 
 #ifndef NGINX_SERVER

src/http/modules/ngx_http_limit_conn_module.c

@@ -10,36 +10,49 @@
 #include <ngx_http.h>
 
 
+#define NGX_HTTP_LIMIT_CONN_PASSED            1
+#define NGX_HTTP_LIMIT_CONN_REJECTED          2
+#define NGX_HTTP_LIMIT_CONN_REJECTED_DRY_RUN  3
+
+
 typedef struct {
-    u_char                     color;
+    u_char                        color;
-    u_char                     len;
+    u_char                        len;
-    u_short                    conn;
+    u_short                       conn;
-    u_char                     data[1];
+    u_char                        data[1];
 } ngx_http_limit_conn_node_t;
 
 
 typedef struct {
-    ngx_shm_zone_t            *shm_zone;
+    ngx_shm_zone_t               *shm_zone;
-    ngx_rbtree_node_t         *node;
+    ngx_rbtree_node_t            *node;
 } ngx_http_limit_conn_cleanup_t;
 
 
 typedef struct {
-    ngx_rbtree_t              *rbtree;
+    ngx_rbtree_t                  rbtree;
-    ngx_http_complex_value_t   key;
+    ngx_rbtree_node_t             sentinel;
+} ngx_http_limit_conn_shctx_t;
+
+
+typedef struct {
+    ngx_http_limit_conn_shctx_t  *sh;
+    ngx_slab_pool_t              *shpool;
+    ngx_http_complex_value_t      key;
 } ngx_http_limit_conn_ctx_t;
 
 
 typedef struct {
-    ngx_shm_zone_t            *shm_zone;
+    ngx_shm_zone_t               *shm_zone;
-    ngx_uint_t                 conn;
+    ngx_uint_t                    conn;
 } ngx_http_limit_conn_limit_t;
 
 
 typedef struct {
-    ngx_array_t                limits;
+    ngx_array_t                   limits;
-    ngx_uint_t                 log_level;
+    ngx_uint_t                    log_level;
-    ngx_uint_t                 status_code;
+    ngx_uint_t                    status_code;
+    ngx_flag_t                    dry_run;
 } ngx_http_limit_conn_conf_t;
 
 
@@ -48,6 +61,8 @@ static ngx_rbtree_node_t *ngx_http_limit_conn_lookup(ngx_rbtree_t *rbtree,
 static void ngx_http_limit_conn_cleanup(void *data);
 static ngx_inline void ngx_http_limit_conn_cleanup_all(ngx_pool_t *pool);
 
+static ngx_int_t ngx_http_limit_conn_status_variable(ngx_http_request_t *r,
+    ngx_http_variable_value_t *v, uintptr_t data);
 static void *ngx_http_limit_conn_create_conf(ngx_conf_t *cf);
 static char *ngx_http_limit_conn_merge_conf(ngx_conf_t *cf, void *parent,
     void *child);
@@ -55,6 +70,7 @@ static char *ngx_http_limit_conn_zone(ngx_conf_t *cf, ngx_command_t *cmd,
     void *conf);
 static char *ngx_http_limit_conn(ngx_conf_t *cf, ngx_command_t *cmd,
     void *conf);
+static ngx_int_t ngx_http_limit_conn_add_variables(ngx_conf_t *cf);
 static ngx_int_t ngx_http_limit_conn_init(ngx_conf_t *cf);
 
 
@@ -102,12 +118,19 @@ static ngx_command_t  ngx_http_limit_conn_commands[] = {
       offsetof(ngx_http_limit_conn_conf_t, status_code),
       &ngx_http_limit_conn_status_bounds },
 
+    { ngx_string("limit_conn_dry_run"),
+      NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_FLAG,
+      ngx_conf_set_flag_slot,
+      NGX_HTTP_LOC_CONF_OFFSET,
+      offsetof(ngx_http_limit_conn_conf_t, dry_run),
+      NULL },
+
       ngx_null_command
 };
 
 
 static ngx_http_module_t  ngx_http_limit_conn_module_ctx = {
-    NULL,                                  /* preconfiguration */
+    ngx_http_limit_conn_add_variables,     /* preconfiguration */
     ngx_http_limit_conn_init,              /* postconfiguration */
 
     NULL,                                  /* create main configuration */
@@ -137,6 +160,22 @@ ngx_module_t  ngx_http_limit_conn_module = {
 };
 
 
+static ngx_http_variable_t  ngx_http_limit_conn_vars[] = {
+
+    { ngx_string("limit_conn_status"), NULL,
+      ngx_http_limit_conn_status_variable, 0, NGX_HTTP_VAR_NOCACHEABLE, 0 },
+
+      ngx_http_null_variable
+};
+
+
+static ngx_str_t  ngx_http_limit_conn_status[] = {
+    ngx_string("PASSED"),
+    ngx_string("REJECTED"),
+    ngx_string("REJECTED_DRY_RUN")
+};
+
+
 static ngx_int_t
 ngx_http_limit_conn_handler(ngx_http_request_t *r)
 {
@@ -144,7 +183,6 @@ ngx_http_limit_conn_handler(ngx_http_request_t *r)
     uint32_t                        hash;
     ngx_str_t                       key;
     ngx_uint_t                      i;
-    ngx_slab_pool_t                *shpool;
     ngx_rbtree_node_t              *node;
     ngx_pool_cleanup_t             *cln;
     ngx_http_limit_conn_ctx_t      *ctx;
@@ -153,7 +191,7 @@ ngx_http_limit_conn_handler(ngx_http_request_t *r)
     ngx_http_limit_conn_limit_t    *limits;
     ngx_http_limit_conn_cleanup_t  *lccln;
 
-    if (r->main->limit_conn_set) {
+    if (r->main->limit_conn_status) {
         return NGX_DECLINED;
     }
 
@@ -179,15 +217,13 @@ ngx_http_limit_conn_handler(ngx_http_request_t *r)
             continue;
         }
 
-        r->main->limit_conn_set = 1;
+        r->main->limit_conn_status = NGX_HTTP_LIMIT_CONN_PASSED;
 
         hash = ngx_crc32_short(key.data, key.len);
 
-        shpool = (ngx_slab_pool_t *) limits[i].shm_zone->shm.addr;
+        ngx_shmtx_lock(&ctx->shpool->mutex);
 
-        ngx_shmtx_lock(&shpool->mutex);
+        node = ngx_http_limit_conn_lookup(&ctx->sh->rbtree, &key, hash);
-
-        node = ngx_http_limit_conn_lookup(ctx->rbtree, &key, hash);
 
         if (node == NULL) {
 
@@ -195,11 +231,20 @@ ngx_http_limit_conn_handler(ngx_http_request_t *r)
                 + offsetof(ngx_http_limit_conn_node_t, data)
                 + key.len;
 
-            node = ngx_slab_alloc_locked(shpool, n);
+            node = ngx_slab_alloc_locked(ctx->shpool, n);
 
             if (node == NULL) {
-                ngx_shmtx_unlock(&shpool->mutex);
+                ngx_shmtx_unlock(&ctx->shpool->mutex);
                 ngx_http_limit_conn_cleanup_all(r->pool);
+
+                if (lccf->dry_run) {
+                    r->main->limit_conn_status =
+                                          NGX_HTTP_LIMIT_CONN_REJECTED_DRY_RUN;
+                    return NGX_DECLINED;
+                }
+
+                r->main->limit_conn_status = NGX_HTTP_LIMIT_CONN_REJECTED;
+
                 return lccf->status_code;
             }
 
@@ -210,7 +255,7 @@ ngx_http_limit_conn_handler(ngx_http_request_t *r)
             lc->conn = 1;
             ngx_memcpy(lc->data, key.data, key.len);
 
-            ngx_rbtree_insert(ctx->rbtree, node);
+            ngx_rbtree_insert(&ctx->sh->rbtree, node);
 
         } else {
 
@@ -218,13 +263,23 @@ ngx_http_limit_conn_handler(ngx_http_request_t *r)
 
             if ((ngx_uint_t) lc->conn >= limits[i].conn) {
 
-                ngx_shmtx_unlock(&shpool->mutex);
+                ngx_shmtx_unlock(&ctx->shpool->mutex);
 
                 ngx_log_error(lccf->log_level, r->connection->log, 0,
-                              "limiting connections by zone \"%V\"",
+                              "limiting connections%s by zone \"%V\"",
+                              lccf->dry_run ? ", dry run," : "",
                               &limits[i].shm_zone->shm.name);
 
                 ngx_http_limit_conn_cleanup_all(r->pool);
+
+                if (lccf->dry_run) {
+                    r->main->limit_conn_status =
+                                          NGX_HTTP_LIMIT_CONN_REJECTED_DRY_RUN;
+                    return NGX_DECLINED;
+                }
+
+                r->main->limit_conn_status = NGX_HTTP_LIMIT_CONN_REJECTED;
+
                 return lccf->status_code;
             }
 
@@ -234,7 +289,7 @@ ngx_http_limit_conn_handler(ngx_http_request_t *r)
         ngx_log_debug2(NGX_LOG_DEBUG_HTTP, r->connection->log, 0,
                        "limit conn: %08Xi %d", node->key, lc->conn);
 
-        ngx_shmtx_unlock(&shpool->mutex);
+        ngx_shmtx_unlock(&ctx->shpool->mutex);
 
         cln = ngx_pool_cleanup_add(r->pool,
                                    sizeof(ngx_http_limit_conn_cleanup_t));
@@ -338,17 +393,15 @@ ngx_http_limit_conn_cleanup(void *data)
 {
     ngx_http_limit_conn_cleanup_t  *lccln = data;
 
-    ngx_slab_pool_t             *shpool;
     ngx_rbtree_node_t           *node;
     ngx_http_limit_conn_ctx_t   *ctx;
     ngx_http_limit_conn_node_t  *lc;
 
     ctx = lccln->shm_zone->data;
-    shpool = (ngx_slab_pool_t *) lccln->shm_zone->shm.addr;
     node = lccln->node;
     lc = (ngx_http_limit_conn_node_t *) &node->color;
 
-    ngx_shmtx_lock(&shpool->mutex);
+    ngx_shmtx_lock(&ctx->shpool->mutex);
 
     ngx_log_debug2(NGX_LOG_DEBUG_HTTP, lccln->shm_zone->shm.log, 0,
                    "limit conn cleanup: %08Xi %d", node->key, lc->conn);
@@ -356,11 +409,11 @@ ngx_http_limit_conn_cleanup(void *data)
     lc->conn--;
 
     if (lc->conn == 0) {
-        ngx_rbtree_delete(ctx->rbtree, node);
+        ngx_rbtree_delete(&ctx->sh->rbtree, node);
-        ngx_slab_free_locked(shpool, node);
+        ngx_slab_free_locked(ctx->shpool, node);
     }
 
-    ngx_shmtx_unlock(&shpool->mutex);
+    ngx_shmtx_unlock(&ctx->shpool->mutex);
 }
 
 
@@ -386,8 +439,6 @@ ngx_http_limit_conn_init_zone(ngx_shm_zone_t *shm_zone, void *data)
     ngx_http_limit_conn_ctx_t  *octx = data;
 
     size_t                      len;
-    ngx_slab_pool_t            *shpool;
-    ngx_rbtree_node_t          *sentinel;
     ngx_http_limit_conn_ctx_t  *ctx;
 
     ctx = shm_zone->data;
@@ -406,48 +457,63 @@ ngx_http_limit_conn_init_zone(ngx_shm_zone_t *shm_zone, void *data)
             return NGX_ERROR;
         }
 
-        ctx->rbtree = octx->rbtree;
+        ctx->sh = octx->sh;
+        ctx->shpool = octx->shpool;
 
         return NGX_OK;
     }
 
-    shpool = (ngx_slab_pool_t *) shm_zone->shm.addr;
+    ctx->shpool = (ngx_slab_pool_t *) shm_zone->shm.addr;
 
     if (shm_zone->shm.exists) {
-        ctx->rbtree = shpool->data;
+        ctx->sh = ctx->shpool->data;
 
         return NGX_OK;
     }
 
-    ctx->rbtree = ngx_slab_alloc(shpool, sizeof(ngx_rbtree_t));
+    ctx->sh = ngx_slab_alloc(ctx->shpool, sizeof(ngx_http_limit_conn_shctx_t));
-    if (ctx->rbtree == NULL) {
+    if (ctx->sh == NULL) {
         return NGX_ERROR;
     }
 
-    shpool->data = ctx->rbtree;
+    ctx->shpool->data = ctx->sh;
 
-    sentinel = ngx_slab_alloc(shpool, sizeof(ngx_rbtree_node_t));
+    ngx_rbtree_init(&ctx->sh->rbtree, &ctx->sh->sentinel,
-    if (sentinel == NULL) {
-        return NGX_ERROR;
-    }
-
-    ngx_rbtree_init(ctx->rbtree, sentinel,
                     ngx_http_limit_conn_rbtree_insert_value);
 
     len = sizeof(" in limit_conn_zone \"\"") + shm_zone->shm.name.len;
 
-    shpool->log_ctx = ngx_slab_alloc(shpool, len);
+    ctx->shpool->log_ctx = ngx_slab_alloc(ctx->shpool, len);
-    if (shpool->log_ctx == NULL) {
+    if (ctx->shpool->log_ctx == NULL) {
         return NGX_ERROR;
     }
 
-    ngx_sprintf(shpool->log_ctx, " in limit_conn_zone \"%V\"%Z",
+    ngx_sprintf(ctx->shpool->log_ctx, " in limit_conn_zone \"%V\"%Z",
                 &shm_zone->shm.name);
 
     return NGX_OK;
 }
 
 
+static ngx_int_t
+ngx_http_limit_conn_status_variable(ngx_http_request_t *r,
+    ngx_http_variable_value_t *v, uintptr_t data)
+{
+    if (r->main->limit_conn_status == 0) {
+        v->not_found = 1;
+        return NGX_OK;
+    }
+
+    v->valid = 1;
+    v->no_cacheable = 0;
+    v->not_found = 0;
+    v->len = ngx_http_limit_conn_status[r->main->limit_conn_status - 1].len;
+    v->data = ngx_http_limit_conn_status[r->main->limit_conn_status - 1].data;
+
+    return NGX_OK;
+}
+
+
 static void *
 ngx_http_limit_conn_create_conf(ngx_conf_t *cf)
 {
@@ -466,6 +532,7 @@ ngx_http_limit_conn_create_conf(ngx_conf_t *cf)
 
     conf->log_level = NGX_CONF_UNSET_UINT;
     conf->status_code = NGX_CONF_UNSET_UINT;
+    conf->dry_run = NGX_CONF_UNSET;
 
     return conf;
 }
@@ -485,6 +552,8 @@ ngx_http_limit_conn_merge_conf(ngx_conf_t *cf, void *parent, void *child)
     ngx_conf_merge_uint_value(conf->status_code, prev->status_code,
                               NGX_HTTP_SERVICE_UNAVAILABLE);
 
+    ngx_conf_merge_value(conf->dry_run, prev->dry_run, 0);
+
     return NGX_CONF_OK;
 }
 
@@ -651,6 +720,25 @@ ngx_http_limit_conn(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
 }
 
 
+static ngx_int_t
+ngx_http_limit_conn_add_variables(ngx_conf_t *cf)
+{
+    ngx_http_variable_t  *var, *v;
+
+    for (v = ngx_http_limit_conn_vars; v->name.len; v++) {
+        var = ngx_http_add_variable(cf, &v->name, v->flags);
+        if (var == NULL) {
+            return NGX_ERROR;
+        }
+
+        var->get_handler = v->get_handler;
+        var->data = v->data;
+    }
+
+    return NGX_OK;
+}
+
+
 static ngx_int_t
 ngx_http_limit_conn_init(ngx_conf_t *cf)
 {

src/http/ngx_http_request.h

@@ -510,9 +510,9 @@ struct ngx_http_request_s {
     /*
      * instead of using the request context data in
      * ngx_http_limit_conn_module and ngx_http_limit_req_module
-     * we use the single bits in the request structure
+     * we use the bit fields in the request structure
      */
-    unsigned                          limit_conn_set:1;
+    unsigned                          limit_conn_status:2;
     unsigned                          limit_req_status:3;
 
     unsigned                          limit_rate_set:1;

src/stream/ngx_stream.h

@@ -226,6 +226,8 @@ struct ngx_stream_session_s {
     unsigned                       stat_processing:1;
 
     unsigned                       health_check:1;
+
+    unsigned                       limit_conn_status:2;
 };
 
 

src/stream/ngx_stream_limit_conn_module.c

@@ -10,35 +10,48 @@
 #include <ngx_stream.h>
 
 
+#define NGX_STREAM_LIMIT_CONN_PASSED            1
+#define NGX_STREAM_LIMIT_CONN_REJECTED          2
+#define NGX_STREAM_LIMIT_CONN_REJECTED_DRY_RUN  3
+
+
 typedef struct {
-    u_char                       color;
+    u_char                          color;
-    u_char                       len;
+    u_char                          len;
-    u_short                      conn;
+    u_short                         conn;
-    u_char                       data[1];
+    u_char                          data[1];
 } ngx_stream_limit_conn_node_t;
 
 
 typedef struct {
-    ngx_shm_zone_t              *shm_zone;
+    ngx_shm_zone_t                 *shm_zone;
-    ngx_rbtree_node_t           *node;
+    ngx_rbtree_node_t              *node;
 } ngx_stream_limit_conn_cleanup_t;
 
 
 typedef struct {
-    ngx_rbtree_t                *rbtree;
+    ngx_rbtree_t                    rbtree;
-    ngx_stream_complex_value_t   key;
+    ngx_rbtree_node_t               sentinel;
+} ngx_stream_limit_conn_shctx_t;
+
+
+typedef struct {
+    ngx_stream_limit_conn_shctx_t  *sh;
+    ngx_slab_pool_t                *shpool;
+    ngx_stream_complex_value_t      key;
 } ngx_stream_limit_conn_ctx_t;
 
 
 typedef struct {
-    ngx_shm_zone_t              *shm_zone;
+    ngx_shm_zone_t                 *shm_zone;
-    ngx_uint_t                   conn;
+    ngx_uint_t                      conn;
 } ngx_stream_limit_conn_limit_t;
 
 
 typedef struct {
-    ngx_array_t                  limits;
+    ngx_array_t                     limits;
-    ngx_uint_t                   log_level;
+    ngx_uint_t                      log_level;
+    ngx_flag_t                      dry_run;
 } ngx_stream_limit_conn_conf_t;
 
 
@@ -47,6 +60,8 @@ static ngx_rbtree_node_t *ngx_stream_limit_conn_lookup(ngx_rbtree_t *rbtree,
 static void ngx_stream_limit_conn_cleanup(void *data);
 static ngx_inline void ngx_stream_limit_conn_cleanup_all(ngx_pool_t *pool);
 
+static ngx_int_t ngx_stream_limit_conn_status_variable(ngx_stream_session_t *s,
+    ngx_stream_variable_value_t *v, uintptr_t data);
 static void *ngx_stream_limit_conn_create_conf(ngx_conf_t *cf);
 static char *ngx_stream_limit_conn_merge_conf(ngx_conf_t *cf, void *parent,
     void *child);
@@ -54,6 +69,7 @@ static char *ngx_stream_limit_conn_zone(ngx_conf_t *cf, ngx_command_t *cmd,
     void *conf);
 static char *ngx_stream_limit_conn(ngx_conf_t *cf, ngx_command_t *cmd,
     void *conf);
+static ngx_int_t ngx_stream_limit_conn_add_variables(ngx_conf_t *cf);
 static ngx_int_t ngx_stream_limit_conn_init(ngx_conf_t *cf);
 
 
@@ -89,12 +105,19 @@ static ngx_command_t  ngx_stream_limit_conn_commands[] = {
       offsetof(ngx_stream_limit_conn_conf_t, log_level),
       &ngx_stream_limit_conn_log_levels },
 
+    { ngx_string("limit_conn_dry_run"),
+      NGX_STREAM_MAIN_CONF|NGX_STREAM_SRV_CONF|NGX_CONF_FLAG,
+      ngx_conf_set_flag_slot,
+      NGX_STREAM_SRV_CONF_OFFSET,
+      offsetof(ngx_stream_limit_conn_conf_t, dry_run),
+      NULL },
+
       ngx_null_command
 };
 
 
 static ngx_stream_module_t  ngx_stream_limit_conn_module_ctx = {
-    NULL,                                  /* preconfiguration */
+    ngx_stream_limit_conn_add_variables,   /* preconfiguration */
     ngx_stream_limit_conn_init,            /* postconfiguration */
 
     NULL,                                  /* create main configuration */
@@ -121,6 +144,22 @@ ngx_module_t  ngx_stream_limit_conn_module = {
 };
 
 
+static ngx_stream_variable_t  ngx_stream_limit_conn_vars[] = {
+
+    { ngx_string("limit_conn_status"), NULL,
+      ngx_stream_limit_conn_status_variable, 0, NGX_STREAM_VAR_NOCACHEABLE, 0 },
+
+      ngx_stream_null_variable
+};
+
+
+static ngx_str_t  ngx_stream_limit_conn_status[] = {
+    ngx_string("PASSED"),
+    ngx_string("REJECTED"),
+    ngx_string("REJECTED_DRY_RUN")
+};
+
+
 static ngx_int_t
 ngx_stream_limit_conn_handler(ngx_stream_session_t *s)
 {
@@ -128,7 +167,6 @@ ngx_stream_limit_conn_handler(ngx_stream_session_t *s)
     uint32_t                          hash;
     ngx_str_t                         key;
     ngx_uint_t                        i;
-    ngx_slab_pool_t                  *shpool;
     ngx_rbtree_node_t                *node;
     ngx_pool_cleanup_t               *cln;
     ngx_stream_limit_conn_ctx_t      *ctx;
@@ -159,13 +197,13 @@ ngx_stream_limit_conn_handler(ngx_stream_session_t *s)
             continue;
         }
 
+        s->limit_conn_status = NGX_STREAM_LIMIT_CONN_PASSED;
+
         hash = ngx_crc32_short(key.data, key.len);
 
-        shpool = (ngx_slab_pool_t *) limits[i].shm_zone->shm.addr;
+        ngx_shmtx_lock(&ctx->shpool->mutex);
 
-        ngx_shmtx_lock(&shpool->mutex);
+        node = ngx_stream_limit_conn_lookup(&ctx->sh->rbtree, &key, hash);
-
-        node = ngx_stream_limit_conn_lookup(ctx->rbtree, &key, hash);
 
         if (node == NULL) {
 
@@ -173,11 +211,20 @@ ngx_stream_limit_conn_handler(ngx_stream_session_t *s)
                 + offsetof(ngx_stream_limit_conn_node_t, data)
                 + key.len;
 
-            node = ngx_slab_alloc_locked(shpool, n);
+            node = ngx_slab_alloc_locked(ctx->shpool, n);
 
             if (node == NULL) {
-                ngx_shmtx_unlock(&shpool->mutex);
+                ngx_shmtx_unlock(&ctx->shpool->mutex);
                 ngx_stream_limit_conn_cleanup_all(s->connection->pool);
+
+                if (lccf->dry_run) {
+                    s->limit_conn_status =
+                                        NGX_STREAM_LIMIT_CONN_REJECTED_DRY_RUN;
+                    return NGX_DECLINED;
+                }
+
+                s->limit_conn_status = NGX_STREAM_LIMIT_CONN_REJECTED;
+
                 return NGX_STREAM_SERVICE_UNAVAILABLE;
             }
 
@@ -188,7 +235,7 @@ ngx_stream_limit_conn_handler(ngx_stream_session_t *s)
             lc->conn = 1;
             ngx_memcpy(lc->data, key.data, key.len);
 
-            ngx_rbtree_insert(ctx->rbtree, node);
+            ngx_rbtree_insert(&ctx->sh->rbtree, node);
 
         } else {
 
@@ -196,13 +243,23 @@ ngx_stream_limit_conn_handler(ngx_stream_session_t *s)
 
             if ((ngx_uint_t) lc->conn >= limits[i].conn) {
 
-                ngx_shmtx_unlock(&shpool->mutex);
+                ngx_shmtx_unlock(&ctx->shpool->mutex);
 
                 ngx_log_error(lccf->log_level, s->connection->log, 0,
-                              "limiting connections by zone \"%V\"",
+                              "limiting connections%s by zone \"%V\"",
+                              lccf->dry_run ? ", dry run," : "",
                               &limits[i].shm_zone->shm.name);
 
                 ngx_stream_limit_conn_cleanup_all(s->connection->pool);
+
+                if (lccf->dry_run) {
+                    s->limit_conn_status =
+                                        NGX_STREAM_LIMIT_CONN_REJECTED_DRY_RUN;
+                    return NGX_DECLINED;
+                }
+
+                s->limit_conn_status = NGX_STREAM_LIMIT_CONN_REJECTED;
+
                 return NGX_STREAM_SERVICE_UNAVAILABLE;
             }
 
@@ -212,7 +269,7 @@ ngx_stream_limit_conn_handler(ngx_stream_session_t *s)
         ngx_log_debug2(NGX_LOG_DEBUG_STREAM, s->connection->log, 0,
                        "limit conn: %08Xi %d", node->key, lc->conn);
 
-        ngx_shmtx_unlock(&shpool->mutex);
+        ngx_shmtx_unlock(&ctx->shpool->mutex);
 
         cln = ngx_pool_cleanup_add(s->connection->pool,
                                    sizeof(ngx_stream_limit_conn_cleanup_t));
@@ -317,17 +374,15 @@ ngx_stream_limit_conn_cleanup(void *data)
 {
     ngx_stream_limit_conn_cleanup_t  *lccln = data;
 
-    ngx_slab_pool_t               *shpool;
     ngx_rbtree_node_t             *node;
     ngx_stream_limit_conn_ctx_t   *ctx;
     ngx_stream_limit_conn_node_t  *lc;
 
     ctx = lccln->shm_zone->data;
-    shpool = (ngx_slab_pool_t *) lccln->shm_zone->shm.addr;
     node = lccln->node;
     lc = (ngx_stream_limit_conn_node_t *) &node->color;
 
-    ngx_shmtx_lock(&shpool->mutex);
+    ngx_shmtx_lock(&ctx->shpool->mutex);
 
     ngx_log_debug2(NGX_LOG_DEBUG_STREAM, lccln->shm_zone->shm.log, 0,
                    "limit conn cleanup: %08Xi %d", node->key, lc->conn);
@@ -335,11 +390,11 @@ ngx_stream_limit_conn_cleanup(void *data)
     lc->conn--;
 
     if (lc->conn == 0) {
-        ngx_rbtree_delete(ctx->rbtree, node);
+        ngx_rbtree_delete(&ctx->sh->rbtree, node);
-        ngx_slab_free_locked(shpool, node);
+        ngx_slab_free_locked(ctx->shpool, node);
     }
 
-    ngx_shmtx_unlock(&shpool->mutex);
+    ngx_shmtx_unlock(&ctx->shpool->mutex);
 }
 
 
@@ -365,8 +420,6 @@ ngx_stream_limit_conn_init_zone(ngx_shm_zone_t *shm_zone, void *data)
     ngx_stream_limit_conn_ctx_t  *octx = data;
 
     size_t                        len;
-    ngx_slab_pool_t              *shpool;
-    ngx_rbtree_node_t            *sentinel;
     ngx_stream_limit_conn_ctx_t  *ctx;
 
     ctx = shm_zone->data;
@@ -385,48 +438,64 @@ ngx_stream_limit_conn_init_zone(ngx_shm_zone_t *shm_zone, void *data)
             return NGX_ERROR;
         }
 
-        ctx->rbtree = octx->rbtree;
+        ctx->sh = octx->sh;
+        ctx->shpool = octx->shpool;
 
         return NGX_OK;
     }
 
-    shpool = (ngx_slab_pool_t *) shm_zone->shm.addr;
+    ctx->shpool = (ngx_slab_pool_t *) shm_zone->shm.addr;
 
     if (shm_zone->shm.exists) {
-        ctx->rbtree = shpool->data;
+        ctx->sh = ctx->shpool->data;
 
         return NGX_OK;
     }
 
-    ctx->rbtree = ngx_slab_alloc(shpool, sizeof(ngx_rbtree_t));
+    ctx->sh = ngx_slab_alloc(ctx->shpool,
-    if (ctx->rbtree == NULL) {
+                             sizeof(ngx_stream_limit_conn_shctx_t));
+    if (ctx->sh == NULL) {
         return NGX_ERROR;
     }
 
-    shpool->data = ctx->rbtree;
+    ctx->shpool->data = ctx->sh;
 
-    sentinel = ngx_slab_alloc(shpool, sizeof(ngx_rbtree_node_t));
+    ngx_rbtree_init(&ctx->sh->rbtree, &ctx->sh->sentinel,
-    if (sentinel == NULL) {
-        return NGX_ERROR;
-    }
-
-    ngx_rbtree_init(ctx->rbtree, sentinel,
                     ngx_stream_limit_conn_rbtree_insert_value);
 
     len = sizeof(" in limit_conn_zone \"\"") + shm_zone->shm.name.len;
 
-    shpool->log_ctx = ngx_slab_alloc(shpool, len);
+    ctx->shpool->log_ctx = ngx_slab_alloc(ctx->shpool, len);
-    if (shpool->log_ctx == NULL) {
+    if (ctx->shpool->log_ctx == NULL) {
         return NGX_ERROR;
     }
 
-    ngx_sprintf(shpool->log_ctx, " in limit_conn_zone \"%V\"%Z",
+    ngx_sprintf(ctx->shpool->log_ctx, " in limit_conn_zone \"%V\"%Z",
                 &shm_zone->shm.name);
 
     return NGX_OK;
 }
 
 
+static ngx_int_t
+ngx_stream_limit_conn_status_variable(ngx_stream_session_t *s,
+    ngx_stream_variable_value_t *v, uintptr_t data)
+{
+    if (s->limit_conn_status == 0) {
+        v->not_found = 1;
+        return NGX_OK;
+    }
+
+    v->valid = 1;
+    v->no_cacheable = 0;
+    v->not_found = 0;
+    v->len = ngx_stream_limit_conn_status[s->limit_conn_status - 1].len;
+    v->data = ngx_stream_limit_conn_status[s->limit_conn_status - 1].data;
+
+    return NGX_OK;
+}
+
+
 static void *
 ngx_stream_limit_conn_create_conf(ngx_conf_t *cf)
 {
@@ -444,6 +513,7 @@ ngx_stream_limit_conn_create_conf(ngx_conf_t *cf)
      */
 
     conf->log_level = NGX_CONF_UNSET_UINT;
+    conf->dry_run = NGX_CONF_UNSET;
 
     return conf;
 }
@@ -461,6 +531,8 @@ ngx_stream_limit_conn_merge_conf(ngx_conf_t *cf, void *parent, void *child)
 
     ngx_conf_merge_uint_value(conf->log_level, prev->log_level, NGX_LOG_ERR);
 
+    ngx_conf_merge_value(conf->dry_run, prev->dry_run, 0);
+
     return NGX_CONF_OK;
 }
 
@@ -627,6 +699,25 @@ ngx_stream_limit_conn(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
 }
 
 
+static ngx_int_t
+ngx_stream_limit_conn_add_variables(ngx_conf_t *cf)
+{
+    ngx_stream_variable_t  *var, *v;
+
+    for (v = ngx_stream_limit_conn_vars; v->name.len; v++) {
+        var = ngx_stream_add_variable(cf, &v->name, v->flags);
+        if (var == NULL) {
+            return NGX_ERROR;
+        }
+
+        var->get_handler = v->get_handler;
+        var->data = v->data;
+    }
+
+    return NGX_OK;
+}
+
+
 static ngx_int_t
 ngx_stream_limit_conn_init(ngx_conf_t *cf)
 {