new file mode 100644
--- /dev/null
+++ b/src/stream/ngx_stream.h
@@ -0,0 +1,215 @@
+
+/*
+ * Copyright (C) Roman Arutyunyan
+ * Copyright (C) Nginx, Inc.
+ */
+
+
+#ifndef _NGX_STREAM_H_INCLUDED_
+#define _NGX_STREAM_H_INCLUDED_
+
+
+#include <ngx_config.h>
+#include <ngx_core.h>
+
+#if (NGX_STREAM_SSL)
+#include <ngx_stream_ssl_module.h>
+#endif
+
+
+typedef struct ngx_stream_session_s  ngx_stream_session_t;
+
+
+#include <ngx_stream_upstream.h>
+#include <ngx_stream_upstream_round_robin.h>
+
+
+typedef struct {
+    void                  **main_conf;
+    void                  **srv_conf;
+} ngx_stream_conf_ctx_t;
+
+
+typedef struct {
+    u_char                  sockaddr[NGX_SOCKADDRLEN];
+    socklen_t               socklen;
+
+    /* server ctx */
+    ngx_stream_conf_ctx_t  *ctx;
+
+    unsigned                bind:1;
+    unsigned                wildcard:1;
+#if (NGX_STREAM_SSL)
+    unsigned                ssl:1;
+#endif
+#if (NGX_HAVE_INET6 && defined IPV6_V6ONLY)
+    unsigned                ipv6only:1;
+#endif
+    unsigned                so_keepalive:2;
+#if (NGX_HAVE_KEEPALIVE_TUNABLE)
+    int                     tcp_keepidle;
+    int                     tcp_keepintvl;
+    int                     tcp_keepcnt;
+#endif
+} ngx_stream_listen_t;
+
+
+typedef struct {
+    ngx_stream_conf_ctx_t  *ctx;
+    ngx_str_t               addr_text;
+#if (NGX_STREAM_SSL)
+    ngx_uint_t              ssl;    /* unsigned   ssl:1; */
+#endif
+} ngx_stream_addr_conf_t;
+
+typedef struct {
+    in_addr_t               addr;
+    ngx_stream_addr_conf_t  conf;
+} ngx_stream_in_addr_t;
+
+
+#if (NGX_HAVE_INET6)
+
+typedef struct {
+    struct in6_addr         addr6;
+    ngx_stream_addr_conf_t  conf;
+} ngx_stream_in6_addr_t;
+
+#endif
+
+
+typedef struct {
+    /* ngx_stream_in_addr_t or ngx_stream_in6_addr_t */
+    void                   *addrs;
+    ngx_uint_t              naddrs;
+} ngx_stream_port_t;
+
+
+typedef struct {
+    int                     family;
+    in_port_t               port;
+    ngx_array_t             addrs;       /* array of ngx_stream_conf_addr_t */
+} ngx_stream_conf_port_t;
+
+
+typedef struct {
+    struct sockaddr        *sockaddr;
+    socklen_t               socklen;
+
+    ngx_stream_conf_ctx_t  *ctx;
+
+    unsigned                bind:1;
+    unsigned                wildcard:1;
+#if (NGX_STREAM_SSL)
+    unsigned                ssl:1;
+#endif
+#if (NGX_HAVE_INET6 && defined IPV6_V6ONLY)
+    unsigned                ipv6only:1;
+#endif
+    unsigned                so_keepalive:2;
+#if (NGX_HAVE_KEEPALIVE_TUNABLE)
+    int                     tcp_keepidle;
+    int                     tcp_keepintvl;
+    int                     tcp_keepcnt;
+#endif
+} ngx_stream_conf_addr_t;
+
+
+typedef struct {
+    ngx_array_t             servers;     /* ngx_stream_core_srv_conf_t */
+    ngx_array_t             listen;      /* ngx_stream_listen_t */
+} ngx_stream_core_main_conf_t;
+
+
+typedef void (*ngx_stream_handler_pt)(ngx_stream_session_t *s);
+
+
+typedef struct {
+    ngx_stream_handler_pt   handler;
+    ngx_stream_conf_ctx_t  *ctx;
+    u_char                 *file_name;
+    ngx_int_t               line;
+    ngx_log_t              *error_log;
+} ngx_stream_core_srv_conf_t;
+
+
+struct ngx_stream_session_s {
+    uint32_t                signature;         /* "STRM" */
+
+    ngx_connection_t       *connection;
+
+    off_t                   received;
+
+    ngx_log_handler_pt      log_handler;
+
+    void                  **ctx;
+    void                  **main_conf;
+    void                  **srv_conf;
+
+    ngx_stream_upstream_t  *upstream;
+};
+
+
+typedef struct {
+    void                 *(*create_main_conf)(ngx_conf_t *cf);
+    char                 *(*init_main_conf)(ngx_conf_t *cf, void *conf);
+
+    void                 *(*create_srv_conf)(ngx_conf_t *cf);
+    char                 *(*merge_srv_conf)(ngx_conf_t *cf, void *prev,
+                                            void *conf);
+} ngx_stream_module_t;
+
+
+#define NGX_STREAM_MODULE       0x4d525453     /* "STRM" */
+
+#define NGX_STREAM_MAIN_CONF    0x02000000
+#define NGX_STREAM_SRV_CONF     0x04000000
+#define NGX_STREAM_UPS_CONF     0x08000000
+
+
+#define NGX_STREAM_MAIN_CONF_OFFSET  offsetof(ngx_stream_conf_ctx_t, main_conf)
+#define NGX_STREAM_SRV_CONF_OFFSET   offsetof(ngx_stream_conf_ctx_t, srv_conf)
+
+
+#define ngx_stream_get_module_ctx(s, module)   (s)->ctx[module.ctx_index]
+#define ngx_stream_set_ctx(s, c, module)       s->ctx[module.ctx_index] = c;
+#define ngx_stream_delete_ctx(s, module)       s->ctx[module.ctx_index] = NULL;
+
+
+#define ngx_stream_get_module_main_conf(s, module)                             \
+    (s)->main_conf[module.ctx_index]
+#define ngx_stream_get_module_srv_conf(s, module)                              \
+    (s)->srv_conf[module.ctx_index]
+
+#define ngx_stream_conf_get_module_main_conf(cf, module)                       \
+    ((ngx_stream_conf_ctx_t *) cf->ctx)->main_conf[module.ctx_index]
+#define ngx_stream_conf_get_module_srv_conf(cf, module)                        \
+    ((ngx_stream_conf_ctx_t *) cf->ctx)->srv_conf[module.ctx_index]
+
+#define ngx_stream_cycle_get_module_main_conf(cycle, module)                   \
+    (cycle->conf_ctx[ngx_stream_module.index] ?                                \
+        ((ngx_stream_conf_ctx_t *) cycle->conf_ctx[ngx_stream_module.index])   \
+            ->main_conf[module.ctx_index]:                                     \
+        NULL)
+
+#define ngx_stream_set_connection_log(c, l)                                    \
+                                                                               \
+    c->log->file = l->file;                                                    \
+    c->log->next = l->next;                                                    \
+    c->log->writer = l->writer;                                                \
+    c->log->wdata = l->wdata;                                                  \
+    if (!(c->log->log_level & NGX_LOG_DEBUG_CONNECTION)) {                     \
+        c->log->log_level = l->log_level;                                      \
+    }
+
+
+void ngx_stream_init_connection(ngx_connection_t *c);
+void ngx_stream_close_connection(ngx_connection_t *c);
+
+
+extern ngx_module_t  ngx_stream_module;
+extern ngx_uint_t    ngx_stream_max_module;
+extern ngx_module_t  ngx_stream_core_module;
+
+
+#endif /* _NGX_STREAM_H_INCLUDED_ */