new file mode 100644
--- /dev/null
+++ b/src/http/modules/ngx_http_referer_module.c
@@ -0,0 +1,309 @@
+
+/*
+ * Copyright (C) Igor Sysoev
+ */
+
+
+#include <ngx_config.h>
+#include <ngx_core.h>
+#include <ngx_http.h>
+
+
+typedef struct {
+    ngx_str_t     name;
+    ngx_uint_t    wildcard;
+} ngx_http_referer_t;
+
+typedef struct {
+    ngx_array_t  *referers;     /* ngx_http_referer_t */
+
+    ngx_flag_t    no_referer;
+    ngx_flag_t    blocked_referer;
+} ngx_http_referer_conf_t;
+
+
+static void * ngx_http_referer_create_conf(ngx_conf_t *cf);
+static char * ngx_http_referer_merge_conf(ngx_conf_t *cf, void *parent,
+    void *child);
+static char *ngx_http_valid_referers(ngx_conf_t *cf, ngx_command_t *cmd,
+    void *conf);
+
+
+static ngx_command_t  ngx_http_referer_commands[] = {
+
+    { ngx_string("valid_referers"),
+      NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_1MORE,
+      ngx_http_valid_referers,
+      NGX_HTTP_LOC_CONF_OFFSET,
+      0,
+      NULL },
+
+      ngx_null_command
+};
+
+
+static ngx_http_module_t  ngx_http_referer_module_ctx = {
+    NULL,                                  /* preconfiguration */
+    NULL,                                  /* postconfiguration */
+
+    NULL,                                  /* create main configuration */
+    NULL,                                  /* init main configuration */
+
+    NULL,                                  /* create server configuration */
+    NULL,                                  /* merge server configuration */
+
+    ngx_http_referer_create_conf,          /* create location configuration */
+    ngx_http_referer_merge_conf            /* merge location configuration */
+};
+
+
+ngx_module_t  ngx_http_referer_module = {
+    NGX_MODULE_V1,
+    &ngx_http_referer_module_ctx,          /* module context */
+    ngx_http_referer_commands,             /* module directives */
+    NGX_HTTP_MODULE,                       /* module type */
+    NULL,                                  /* init master */
+    NULL,                                  /* init module */
+    NULL,                                  /* init process */
+    NULL,                                  /* init thread */
+    NULL,                                  /* exit thread */
+    NULL,                                  /* exit process */
+    NULL,                                  /* exit master */
+    NGX_MODULE_V1_PADDING
+};
+
+
+static ngx_int_t
+ngx_http_referer_variable(ngx_http_request_t *r, ngx_http_variable_value_t *v,
+     uintptr_t data)
+{
+    u_char                  *ref;
+    size_t                   len;
+    ngx_uint_t               i, n;
+    ngx_http_referer_t       *refs;
+    ngx_http_referer_conf_t  *cf;
+
+    cf = ngx_http_get_module_loc_conf(r, ngx_http_referer_module);
+
+    if (cf->referers == NULL) {
+        *v = ngx_http_variable_null_value;
+        return NGX_OK;
+    }
+
+    if (r->headers_in.referer == NULL) {
+        if (cf->no_referer) {
+            *v = ngx_http_variable_null_value;
+            return NGX_OK;
+
+        } else {
+            *v = ngx_http_variable_true_value;
+            return NGX_OK;
+        }
+    }
+
+    len = r->headers_in.referer->value.len;
+    ref = r->headers_in.referer->value.data;
+
+    if (len < sizeof("http://i.ru") - 1
+        || (ngx_strncasecmp(ref, "http://", 7) != 0))
+    {
+        if (cf->blocked_referer) {
+            *v = ngx_http_variable_null_value;
+            return NGX_OK;
+
+        } else {
+            *v = ngx_http_variable_true_value;
+            return NGX_OK;
+        }
+    }
+
+    len -= 7;
+    ref += 7;
+
+    refs = cf->referers->elts;
+    for (i = 0; i < cf->referers->nelts; i++ ){
+
+        if (refs[i].name.len > len) {
+            continue;
+        }
+
+        if (refs[i].wildcard) {
+            for (n = 0; n < len; n++) {
+                if (ref[n] == '/' || ref[n] == ':') {
+                    break;
+                }
+
+                if (ref[n] != '.') {
+                    continue;
+                }
+
+                if (ngx_strncmp(&ref[n], refs[i].name.data,
+                                refs[i].name.len) == 0)
+                {
+                    *v = ngx_http_variable_null_value;
+                    return NGX_OK;
+                }
+            }
+
+        } else {
+            if (ngx_strncasecmp(refs[i].name.data, ref, refs[i].name.len) == 0)
+            {
+                *v = ngx_http_variable_null_value;
+                return NGX_OK;
+            }
+        }
+    }
+
+    *v = ngx_http_variable_true_value;
+
+    return NGX_OK;
+}
+
+
+static void *
+ngx_http_referer_create_conf(ngx_conf_t *cf)
+{
+    ngx_http_referer_conf_t  *conf;
+
+    conf = ngx_palloc(cf->pool, sizeof(ngx_http_referer_conf_t));
+    if (conf == NULL) {
+        return NGX_CONF_ERROR;
+    }
+
+    conf->referers = NULL;
+    conf->no_referer = NGX_CONF_UNSET;
+    conf->blocked_referer = NGX_CONF_UNSET;
+
+    return conf;
+}
+
+
+static char *
+ngx_http_referer_merge_conf(ngx_conf_t *cf, void *parent, void *child)
+{
+    ngx_http_referer_conf_t *prev = parent;
+    ngx_http_referer_conf_t *conf = child;
+
+    if (conf->referers == NULL) {
+        conf->referers = prev->referers;
+        ngx_conf_merge_value(conf->no_referer, prev->no_referer, 0);
+        ngx_conf_merge_value(conf->blocked_referer, prev->blocked_referer, 0);
+    }
+
+    if (conf->no_referer == NGX_CONF_UNSET) {
+        conf->no_referer = 0;
+    }
+
+    if (conf->blocked_referer == NGX_CONF_UNSET) {
+        conf->blocked_referer = 0;
+    }
+
+    return NGX_CONF_OK;
+}
+
+
+static char *
+ngx_http_valid_referers(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
+{
+    ngx_http_referer_conf_t  *lcf = conf;
+
+    ngx_uint_t                 i, server_names;
+    ngx_str_t                 *value, name;
+    ngx_http_referer_t        *ref;
+    ngx_http_variable_t       *var;
+    ngx_http_server_name_t    *sn;
+    ngx_http_core_srv_conf_t  *cscf;
+
+    name.len = sizeof("invalid_referer") - 1;
+    name.data = (u_char *) "invalid_referer";
+
+    var = ngx_http_add_variable(cf, &name, NGX_HTTP_VAR_CHANGABLE);
+    if (var == NULL) {
+        return NGX_CONF_ERROR;
+    }
+
+    var->handler = ngx_http_referer_variable;
+
+    cscf = ngx_http_conf_get_module_srv_conf(cf, ngx_http_core_module);
+
+    if (lcf->referers == NULL) {
+        lcf->referers = ngx_array_create(cf->pool,
+                                    cf->args->nelts + cscf->server_names.nelts,
+                                    sizeof(ngx_http_referer_t));
+        if (lcf->referers == NULL) {
+            return NGX_CONF_ERROR;
+        }
+    }
+
+    value = cf->args->elts;
+    server_names = 0;
+
+    for (i = 1; i < cf->args->nelts; i++) {
+        if (value[i].len == 0) {
+            ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
+                               "invalid referer \"%V\"", &value[i]);
+            return NGX_CONF_ERROR;
+        }
+
+        if (ngx_strcmp(value[i].data, "none") == 0) {
+            lcf->no_referer = 1;
+            continue;
+        }
+
+        if (ngx_strcmp(value[i].data, "blocked") == 0) {
+            lcf->blocked_referer = 1;
+            continue;
+        }
+
+        if (ngx_strcmp(value[i].data, "server_names") == 0) {
+            server_names = 1;
+            continue;
+        }
+
+        ref = ngx_array_push(lcf->referers);
+        if (ref == NULL) {
+            return NGX_CONF_ERROR;
+        }
+
+        if (value[i].data[0] != '*') {
+            ref->name = value[i];
+            ref->wildcard = 0;
+            continue;
+        }
+
+
+        if (value[i].data[1] != '.') {
+            ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
+                               "invalid wildcard referer \"%V\"", &value[i]);
+            return NGX_CONF_ERROR;
+        }
+
+        ref->name.len = value[i].len - 1;
+        ref->name.data = value[i].data + 1;
+        ref->wildcard = 1;
+    }
+
+    if (!server_names) {
+        return NGX_CONF_OK;
+    }
+
+    sn = cscf->server_names.elts;
+    for (i = 0; i < cscf->server_names.nelts; i++) {
+        ref = ngx_array_push(lcf->referers);
+        if (ref == NULL) {
+            return NGX_CONF_ERROR;
+        }
+
+        ref->name.len = sn[i].name.len + 1;
+        ref->name.data = ngx_palloc(cf->pool, ref->name.len);
+        if (ref->name.data == NULL) {
+            return NGX_CONF_ERROR;
+        }
+
+        ngx_memcpy(ref->name.data, sn[i].name.data, sn[i].name.len);
+        ref->name.data[sn[i].name.len] = '/';
+        ref->wildcard = sn[i].wildcard;
+    }
+
+    return NGX_CONF_OK;
+}