new file mode 100644
--- /dev/null
+++ b/src/http/v3/ngx_http_v3.c
@@ -0,0 +1,85 @@
+
+/*
+ * Copyright (C) Roman Arutyunyan
+ * Copyright (C) Nginx, Inc.
+ */
+
+
+#include <ngx_config.h>
+#include <ngx_core.h>
+#include <ngx_http.h>
+
+
+static void ngx_http_v3_keepalive_handler(ngx_event_t *ev);
+static void ngx_http_v3_cleanup_session(void *data);
+
+
+ngx_int_t
+ngx_http_v3_init_session(ngx_connection_t *c)
+{
+    ngx_connection_t       *pc;
+    ngx_pool_cleanup_t     *cln;
+    ngx_http_connection_t  *hc;
+    ngx_http_v3_session_t  *h3c;
+
+    pc = c->quic->parent;
+    hc = pc->data;
+
+    if (hc->v3_session) {
+        return NGX_OK;
+    }
+
+    ngx_log_debug0(NGX_LOG_DEBUG_HTTP, c->log, 0, "http3 init session");
+
+    h3c = ngx_pcalloc(pc->pool, sizeof(ngx_http_v3_session_t));
+    if (h3c == NULL) {
+        return NGX_ERROR;
+    }
+
+    h3c->max_push_id = (uint64_t) -1;
+
+    ngx_queue_init(&h3c->blocked);
+    ngx_queue_init(&h3c->pushing);
+
+    h3c->keepalive.log = pc->log;
+    h3c->keepalive.data = pc;
+    h3c->keepalive.handler = ngx_http_v3_keepalive_handler;
+    h3c->keepalive.cancelable = 1;
+
+    cln = ngx_pool_cleanup_add(pc->pool, 0);
+    if (cln == NULL) {
+        return NGX_ERROR;
+    }
+
+    cln->handler = ngx_http_v3_cleanup_session;
+    cln->data = h3c;
+
+    hc->v3_session = h3c;
+
+    return ngx_http_v3_send_settings(c);
+}
+
+
+static void
+ngx_http_v3_keepalive_handler(ngx_event_t *ev)
+{
+    ngx_connection_t  *c;
+
+    c = ev->data;
+
+    ngx_log_debug0(NGX_LOG_DEBUG_HTTP, c->log, 0, "http3 keepalive handler");
+
+    ngx_quic_finalize_connection(c, NGX_HTTP_V3_ERR_NO_ERROR,
+                                 "keepalive timeout");
+}
+
+
+static void
+ngx_http_v3_cleanup_session(void *data)
+{
+    ngx_http_v3_session_t  *h3c = data;
+
+    if (h3c->keepalive.timer_set) {
+        ngx_del_timer(&h3c->keepalive);
+    }
+}