diff src/http/v2/ngx_http_v2.c @ 6246:257b51c37c5a

The HTTP/2 implementation (RFC 7240, 7241). The SPDY support is removed, as it's incompatible with the new module.
author Valentin Bartenev <vbart@nginx.com>
date Fri, 11 Sep 2015 20:13:06 +0300
parents
children f5380c244cd7
line wrap: on
line diff
new file mode 100644
--- /dev/null
+++ b/src/http/v2/ngx_http_v2.c
@@ -0,0 +1,3964 @@
+
+/*
+ * Copyright (C) Nginx, Inc.
+ * Copyright (C) Valentin V. Bartenev
+ */
+
+
+#include <ngx_config.h>
+#include <ngx_core.h>
+#include <ngx_http.h>
+#include <ngx_http_v2_module.h>
+
+
+/* errors */
+#define NGX_HTTP_V2_NO_ERROR                     0x0
+#define NGX_HTTP_V2_PROTOCOL_ERROR               0x1
+#define NGX_HTTP_V2_INTERNAL_ERROR               0x2
+#define NGX_HTTP_V2_FLOW_CTRL_ERROR              0x3
+#define NGX_HTTP_V2_SETTINGS_TIMEOUT             0x4
+#define NGX_HTTP_V2_STREAM_CLOSED                0x5
+#define NGX_HTTP_V2_SIZE_ERROR                   0x6
+#define NGX_HTTP_V2_REFUSED_STREAM               0x7
+#define NGX_HTTP_V2_CANCEL                       0x8
+#define NGX_HTTP_V2_COMP_ERROR                   0x9
+#define NGX_HTTP_V2_CONNECT_ERROR                0xa
+#define NGX_HTTP_V2_ENHANCE_YOUR_CALM            0xb
+#define NGX_HTTP_V2_INADEQUATE_SECURITY          0xc
+#define NGX_HTTP_V2_HTTP_1_1_REQUIRED            0xd
+
+/* frame sizes */
+#define NGX_HTTP_V2_RST_STREAM_SIZE              4
+#define NGX_HTTP_V2_PRIORITY_SIZE                5
+#define NGX_HTTP_V2_PING_SIZE                    8
+#define NGX_HTTP_V2_GOAWAY_SIZE                  8
+#define NGX_HTTP_V2_WINDOW_UPDATE_SIZE           4
+
+#define NGX_HTTP_V2_STREAM_ID_SIZE               4
+
+#define NGX_HTTP_V2_SETTINGS_PARAM_SIZE          6
+
+/* settings fields */
+#define NGX_HTTP_V2_HEADER_TABLE_SIZE_SETTING    0x1
+#define NGX_HTTP_V2_MAX_STREAMS_SETTING          0x3
+#define NGX_HTTP_V2_INIT_WINDOW_SIZE_SETTING     0x4
+#define NGX_HTTP_V2_MAX_FRAME_SIZE_SETTING       0x5
+
+#define NGX_HTTP_V2_FRAME_BUFFER_SIZE            24
+
+#define NGX_HTTP_V2_DEFAULT_FRAME_SIZE           (1 << 14)
+
+#define NGX_HTTP_V2_MAX_WINDOW                   ((1U << 31) - 1)
+#define NGX_HTTP_V2_DEFAULT_WINDOW               65535
+
+#define NGX_HTTP_V2_ROOT                         (void *) -1
+
+
+static void ngx_http_v2_read_handler(ngx_event_t *rev);
+static void ngx_http_v2_write_handler(ngx_event_t *wev);
+static void ngx_http_v2_handle_connection(ngx_http_v2_connection_t *h2c);
+
+static u_char *ngx_http_v2_state_proxy_protocol(ngx_http_v2_connection_t *h2c,
+    u_char *pos, u_char *end);
+static u_char *ngx_http_v2_state_preface(ngx_http_v2_connection_t *h2c,
+    u_char *pos, u_char *end);
+static u_char *ngx_http_v2_state_preface_end(ngx_http_v2_connection_t *h2c,
+    u_char *pos, u_char *end);
+static u_char *ngx_http_v2_state_head(ngx_http_v2_connection_t *h2c,
+    u_char *pos, u_char *end);
+static u_char *ngx_http_v2_state_data(ngx_http_v2_connection_t *h2c,
+    u_char *pos, u_char *end);
+static u_char *ngx_http_v2_state_read_data(ngx_http_v2_connection_t *h2c,
+    u_char *pos, u_char *end);
+static u_char *ngx_http_v2_state_headers(ngx_http_v2_connection_t *h2c,
+    u_char *pos, u_char *end);
+static u_char *ngx_http_v2_state_header_block(ngx_http_v2_connection_t *h2c,
+    u_char *pos, u_char *end);
+static u_char *ngx_http_v2_state_field_len(ngx_http_v2_connection_t *h2c,
+    u_char *pos, u_char *end);
+static u_char *ngx_http_v2_state_field_huff(ngx_http_v2_connection_t *h2c,
+    u_char *pos, u_char *end);
+static u_char *ngx_http_v2_state_field_raw(ngx_http_v2_connection_t *h2c,
+    u_char *pos, u_char *end);
+static u_char *ngx_http_v2_state_field_skip(ngx_http_v2_connection_t *h2c,
+    u_char *pos, u_char *end);
+static u_char *ngx_http_v2_state_process_header(ngx_http_v2_connection_t *h2c,
+    u_char *pos, u_char *end);
+static u_char *ngx_http_v2_state_header_complete(ngx_http_v2_connection_t *h2c,
+    u_char *pos, u_char *end);
+static u_char *ngx_http_v2_state_priority(ngx_http_v2_connection_t *h2c,
+    u_char *pos, u_char *end);
+static u_char *ngx_http_v2_state_rst_stream(ngx_http_v2_connection_t *h2c,
+    u_char *pos, u_char *end);
+static u_char *ngx_http_v2_state_settings(ngx_http_v2_connection_t *h2c,
+    u_char *pos, u_char *end);
+static u_char *ngx_http_v2_state_settings_params(ngx_http_v2_connection_t *h2c,
+    u_char *pos, u_char *end);
+static u_char *ngx_http_v2_state_push_promise(ngx_http_v2_connection_t *h2c,
+    u_char *pos, u_char *end);
+static u_char *ngx_http_v2_state_ping(ngx_http_v2_connection_t *h2c,
+    u_char *pos, u_char *end);
+static u_char *ngx_http_v2_state_goaway(ngx_http_v2_connection_t *h2c,
+    u_char *pos, u_char *end);
+static u_char *ngx_http_v2_state_window_update(ngx_http_v2_connection_t *h2c,
+    u_char *pos, u_char *end);
+static u_char *ngx_http_v2_state_continuation(ngx_http_v2_connection_t *h2c,
+    u_char *pos, u_char *end);
+static u_char *ngx_http_v2_state_complete(ngx_http_v2_connection_t *h2c,
+    u_char *pos, u_char *end);
+static u_char *ngx_http_v2_state_skip_padded(ngx_http_v2_connection_t *h2c,
+    u_char *pos, u_char *end);
+static u_char *ngx_http_v2_state_skip(ngx_http_v2_connection_t *h2c,
+    u_char *pos, u_char *end);
+static u_char *ngx_http_v2_state_skip_headers(ngx_http_v2_connection_t *h2c,
+    u_char *pos, u_char *end);
+static u_char *ngx_http_v2_state_save(ngx_http_v2_connection_t *h2c,
+    u_char *pos, u_char *end, ngx_http_v2_handler_pt handler);
+static u_char *ngx_http_v2_connection_error(ngx_http_v2_connection_t *h2c,
+    ngx_uint_t err);
+
+static ngx_int_t ngx_http_v2_parse_int(ngx_http_v2_connection_t *h2c,
+    u_char **pos, u_char *end, ngx_uint_t prefix);
+
+static ngx_http_v2_stream_t *ngx_http_v2_create_stream(
+    ngx_http_v2_connection_t *h2c);
+static ngx_http_v2_node_t *ngx_http_v2_get_node_by_id(
+    ngx_http_v2_connection_t *h2c, ngx_uint_t sid, ngx_uint_t alloc);
+static ngx_http_v2_node_t *ngx_http_v2_get_closed_node(
+    ngx_http_v2_connection_t *h2c);
+#define ngx_http_v2_index_size(h2scf)  (h2scf->streams_index_mask + 1)
+#define ngx_http_v2_index(h2scf, sid)  ((sid >> 1) & h2scf->streams_index_mask)
+
+static ngx_int_t ngx_http_v2_send_settings(ngx_http_v2_connection_t *h2c,
+    ngx_uint_t ack);
+static ngx_int_t ngx_http_v2_settings_frame_handler(
+    ngx_http_v2_connection_t *h2c, ngx_http_v2_out_frame_t *frame);
+static ngx_int_t ngx_http_v2_send_window_update(ngx_http_v2_connection_t *h2c,
+    ngx_uint_t sid, size_t window);
+static ngx_int_t ngx_http_v2_send_rst_stream(ngx_http_v2_connection_t *h2c,
+    ngx_uint_t sid, ngx_uint_t status);
+
+static ngx_http_v2_out_frame_t *ngx_http_v2_get_frame(
+    ngx_http_v2_connection_t *h2c, size_t length, ngx_uint_t type,
+    u_char flags, ngx_uint_t sid);
+static ngx_int_t ngx_http_v2_frame_handler(ngx_http_v2_connection_t *h2c,
+    ngx_http_v2_out_frame_t *frame);
+
+static ngx_int_t ngx_http_v2_validate_header(ngx_http_request_t *r,
+    ngx_http_v2_header_t *header);
+static ngx_int_t ngx_http_v2_pseudo_header(ngx_http_request_t *r,
+    ngx_http_v2_header_t *header);
+static ngx_int_t ngx_http_v2_parse_path(ngx_http_request_t *r,
+    ngx_http_v2_header_t *header);
+static ngx_int_t ngx_http_v2_parse_method(ngx_http_request_t *r,
+    ngx_http_v2_header_t *header);
+static ngx_int_t ngx_http_v2_parse_scheme(ngx_http_request_t *r,
+    ngx_http_v2_header_t *header);
+static ngx_int_t ngx_http_v2_parse_authority(ngx_http_request_t *r,
+    ngx_http_v2_header_t *header);
+static ngx_int_t ngx_http_v2_construct_request_line(ngx_http_request_t *r);
+static ngx_int_t ngx_http_v2_cookie(ngx_http_request_t *r,
+    ngx_http_v2_header_t *header);
+static ngx_int_t ngx_http_v2_construct_cookie_header(ngx_http_request_t *r);
+static void ngx_http_v2_run_request(ngx_http_request_t *r);
+static ngx_int_t ngx_http_v2_init_request_body(ngx_http_request_t *r);
+
+static ngx_int_t ngx_http_v2_terminate_stream(ngx_http_v2_connection_t *h2c,
+    ngx_http_v2_stream_t *stream, ngx_uint_t status);
+static void ngx_http_v2_close_stream_handler(ngx_event_t *ev);
+static void ngx_http_v2_handle_connection_handler(ngx_event_t *rev);
+static void ngx_http_v2_idle_handler(ngx_event_t *rev);
+static void ngx_http_v2_finalize_connection(ngx_http_v2_connection_t *h2c,
+    ngx_uint_t status);
+
+static ngx_int_t ngx_http_v2_adjust_windows(ngx_http_v2_connection_t *h2c,
+    ssize_t delta);
+static void ngx_http_v2_set_dependency(ngx_http_v2_connection_t *h2c,
+    ngx_http_v2_node_t *node, ngx_uint_t depend, ngx_uint_t exclusive);
+static void ngx_http_v2_node_children_update(ngx_http_v2_node_t *node);
+
+static void ngx_http_v2_pool_cleanup(void *data);
+
+
+static ngx_http_v2_handler_pt ngx_http_v2_frame_states[] = {
+    ngx_http_v2_state_data,
+    ngx_http_v2_state_headers,
+    ngx_http_v2_state_priority,
+    ngx_http_v2_state_rst_stream,
+    ngx_http_v2_state_settings,
+    ngx_http_v2_state_push_promise,
+    ngx_http_v2_state_ping,
+    ngx_http_v2_state_goaway,
+    ngx_http_v2_state_window_update,
+    ngx_http_v2_state_continuation
+};
+
+#define NGX_HTTP_V2_FRAME_STATES                                              \
+    (sizeof(ngx_http_v2_frame_states) / sizeof(ngx_http_v2_handler_pt))
+
+
+void
+ngx_http_v2_init(ngx_event_t *rev)
+{
+    ngx_connection_t          *c;
+    ngx_pool_cleanup_t        *cln;
+    ngx_http_connection_t     *hc;
+    ngx_http_v2_srv_conf_t    *h2scf;
+    ngx_http_v2_main_conf_t   *h2mcf;
+    ngx_http_v2_connection_t  *h2c;
+
+    c = rev->data;
+    hc = c->data;
+
+    ngx_log_debug0(NGX_LOG_DEBUG_HTTP, c->log, 0, "init http2 connection");
+
+    c->log->action = "processing HTTP/2 connection";
+
+    h2mcf = ngx_http_get_module_main_conf(hc->conf_ctx, ngx_http_v2_module);
+
+    if (h2mcf->recv_buffer == NULL) {
+        h2mcf->recv_buffer = ngx_palloc(ngx_cycle->pool,
+                                        h2mcf->recv_buffer_size);
+        if (h2mcf->recv_buffer == NULL) {
+            ngx_http_close_connection(c);
+            return;
+        }
+    }
+
+    h2c = ngx_pcalloc(c->pool, sizeof(ngx_http_v2_connection_t));
+    if (h2c == NULL) {
+        ngx_http_close_connection(c);
+        return;
+    }
+
+    h2c->connection = c;
+    h2c->http_connection = hc;
+
+    h2c->send_window = NGX_HTTP_V2_DEFAULT_WINDOW;
+    h2c->recv_window = NGX_HTTP_V2_MAX_WINDOW;
+
+    h2c->init_window = NGX_HTTP_V2_DEFAULT_WINDOW;
+
+    h2c->frame_size = NGX_HTTP_V2_DEFAULT_FRAME_SIZE;
+
+    h2scf = ngx_http_get_module_srv_conf(hc->conf_ctx, ngx_http_v2_module);
+
+    h2c->pool = ngx_create_pool(h2scf->pool_size, h2c->connection->log);
+    if (h2c->pool == NULL) {
+        ngx_http_close_connection(c);
+        return;
+    }
+
+    cln = ngx_pool_cleanup_add(c->pool, sizeof(ngx_pool_cleanup_file_t));
+    if (cln == NULL) {
+        ngx_http_close_connection(c);
+        return;
+    }
+
+    cln->handler = ngx_http_v2_pool_cleanup;
+    cln->data = h2c;
+
+    h2c->streams_index = ngx_pcalloc(c->pool, ngx_http_v2_index_size(h2scf)
+                                              * sizeof(ngx_http_v2_node_t *));
+    if (h2c->streams_index == NULL) {
+        ngx_http_close_connection(c);
+        return;
+    }
+
+    if (ngx_http_v2_send_settings(h2c, 0) == NGX_ERROR) {
+        ngx_http_close_connection(c);
+        return;
+    }
+
+    if (ngx_http_v2_send_window_update(h2c, 0, NGX_HTTP_V2_MAX_WINDOW
+                                               - NGX_HTTP_V2_DEFAULT_WINDOW)
+        == NGX_ERROR)
+    {
+        ngx_http_close_connection(c);
+        return;
+    }
+
+    h2c->state.handler = hc->proxy_protocol ? ngx_http_v2_state_proxy_protocol
+                                            : ngx_http_v2_state_preface;
+
+    ngx_queue_init(&h2c->waiting);
+    ngx_queue_init(&h2c->posted);
+    ngx_queue_init(&h2c->dependencies);
+    ngx_queue_init(&h2c->closed);
+
+    c->data = h2c;
+
+    rev->handler = ngx_http_v2_read_handler;
+    c->write->handler = ngx_http_v2_write_handler;
+
+    ngx_http_v2_read_handler(rev);
+}
+
+
+static void
+ngx_http_v2_read_handler(ngx_event_t *rev)
+{
+    u_char                    *p, *end;
+    size_t                     available;
+    ssize_t                    n;
+    ngx_connection_t          *c;
+    ngx_http_v2_main_conf_t   *h2mcf;
+    ngx_http_v2_connection_t  *h2c;
+
+    c = rev->data;
+    h2c = c->data;
+
+    if (rev->timedout) {
+        ngx_log_error(NGX_LOG_INFO, c->log, NGX_ETIMEDOUT, "client timed out");
+        ngx_http_v2_finalize_connection(h2c, NGX_HTTP_V2_PROTOCOL_ERROR);
+        return;
+    }
+
+    ngx_log_debug0(NGX_LOG_DEBUG_HTTP, c->log, 0, "http2 read handler");
+
+    h2c->blocked = 1;
+
+    h2mcf = ngx_http_get_module_main_conf(h2c->http_connection->conf_ctx,
+                                          ngx_http_v2_module);
+
+    available = h2mcf->recv_buffer_size - 2 * NGX_HTTP_V2_STATE_BUFFER_SIZE;
+
+    do {
+        p = h2mcf->recv_buffer;
+
+        ngx_memcpy(p, h2c->state.buffer, NGX_HTTP_V2_STATE_BUFFER_SIZE);
+        end = p + h2c->state.buffer_used;
+
+        n = c->recv(c, end, available);
+
+        if (n == NGX_AGAIN) {
+            break;
+        }
+
+        if (n == 0 && (h2c->state.incomplete || h2c->processing)) {
+            ngx_log_error(NGX_LOG_INFO, c->log, 0,
+                          "client prematurely closed connection");
+        }
+
+        if (n == 0 || n == NGX_ERROR) {
+            c->error = 1;
+            ngx_http_v2_finalize_connection(h2c, 0);
+            return;
+        }
+
+        end += n;
+
+        h2c->state.buffer_used = 0;
+        h2c->state.incomplete = 0;
+
+        do {
+            p = h2c->state.handler(h2c, p, end);
+
+            if (p == NULL) {
+                return;
+            }
+
+        } while (p != end);
+
+    } while (rev->ready);
+
+    if (ngx_handle_read_event(rev, 0) != NGX_OK) {
+        ngx_http_v2_finalize_connection(h2c, NGX_HTTP_V2_INTERNAL_ERROR);
+        return;
+    }
+
+    if (h2c->last_out && ngx_http_v2_send_output_queue(h2c) == NGX_ERROR) {
+        ngx_http_v2_finalize_connection(h2c, 0);
+        return;
+    }
+
+    h2c->blocked = 0;
+
+    if (h2c->processing) {
+        if (rev->timer_set) {
+            ngx_del_timer(rev);
+        }
+
+        return;
+    }
+
+    ngx_http_v2_handle_connection(h2c);
+}
+
+
+static void
+ngx_http_v2_write_handler(ngx_event_t *wev)
+{
+    ngx_int_t                  rc;
+    ngx_queue_t               *q;
+    ngx_connection_t          *c;
+    ngx_http_v2_stream_t      *stream;
+    ngx_http_v2_connection_t  *h2c;
+
+    c = wev->data;
+    h2c = c->data;
+
+    if (wev->timedout) {
+        ngx_log_debug0(NGX_LOG_DEBUG_HTTP, c->log, 0,
+                       "http2 write event timed out");
+        c->error = 1;
+        ngx_http_v2_finalize_connection(h2c, 0);
+        return;
+    }
+
+    ngx_log_debug0(NGX_LOG_DEBUG_HTTP, c->log, 0, "http2 write handler");
+
+    h2c->blocked = 1;
+
+    rc = ngx_http_v2_send_output_queue(h2c);
+
+    if (rc == NGX_ERROR) {
+        ngx_http_v2_finalize_connection(h2c, 0);
+        return;
+    }
+
+    while (!ngx_queue_empty(&h2c->posted)) {
+        q = ngx_queue_head(&h2c->posted);
+
+        ngx_queue_remove(q);
+
+        stream = ngx_queue_data(q, ngx_http_v2_stream_t, queue);
+
+        stream->handled = 0;
+
+        ngx_log_debug1(NGX_LOG_DEBUG_HTTP, c->log, 0,
+                       "run http2 stream %ui", stream->node->id);
+
+        wev = stream->request->connection->write;
+        wev->handler(wev);
+    }
+
+    h2c->blocked = 0;
+
+    if (rc == NGX_AGAIN) {
+        return;
+    }
+
+    ngx_http_v2_handle_connection(h2c);
+}
+
+
+ngx_int_t
+ngx_http_v2_send_output_queue(ngx_http_v2_connection_t *h2c)
+{
+    int                        tcp_nodelay;
+    ngx_chain_t               *cl;
+    ngx_event_t               *wev;
+    ngx_connection_t          *c;
+    ngx_http_v2_out_frame_t   *out, *frame, *fn;
+    ngx_http_core_loc_conf_t  *clcf;
+
+    c = h2c->connection;
+
+    if (c->error) {
+        return NGX_ERROR;
+    }
+
+    wev = c->write;
+
+    if (!wev->ready) {
+        return NGX_OK;
+    }
+
+    cl = NULL;
+    out = NULL;
+
+    for (frame = h2c->last_out; frame; frame = fn) {
+        frame->last->next = cl;
+        cl = frame->first;
+
+        fn = frame->next;
+        frame->next = out;
+        out = frame;
+
+        ngx_log_debug4(NGX_LOG_DEBUG_HTTP, c->log, 0,
+                       "http2 frame out: %p sid:%ui bl:%d len:%uz",
+                       out, out->stream ? out->stream->node->id : 0,
+                       out->blocked, out->length);
+    }
+
+    cl = c->send_chain(c, cl, 0);
+
+    if (cl == NGX_CHAIN_ERROR) {
+        goto error;
+    }
+
+    clcf = ngx_http_get_module_loc_conf(h2c->http_connection->conf_ctx,
+                                        ngx_http_core_module);
+
+    if (ngx_handle_write_event(wev, clcf->send_lowat) != NGX_OK) {
+        goto error;
+    }
+
+    if (c->tcp_nopush == NGX_TCP_NOPUSH_SET) {
+        if (ngx_tcp_push(c->fd) == -1) {
+            ngx_connection_error(c, ngx_socket_errno, ngx_tcp_push_n " failed");
+            goto error;
+        }
+
+        c->tcp_nopush = NGX_TCP_NOPUSH_UNSET;
+        tcp_nodelay = ngx_tcp_nodelay_and_tcp_nopush ? 1 : 0;
+
+    } else {
+        tcp_nodelay = 1;
+    }
+
+    if (tcp_nodelay
+        && clcf->tcp_nodelay
+        && c->tcp_nodelay == NGX_TCP_NODELAY_UNSET)
+    {
+        ngx_log_debug0(NGX_LOG_DEBUG_HTTP, c->log, 0, "tcp_nodelay");
+
+        if (setsockopt(c->fd, IPPROTO_TCP, TCP_NODELAY,
+                       (const void *) &tcp_nodelay, sizeof(int))
+            == -1)
+        {
+#if (NGX_SOLARIS)
+            /* Solaris returns EINVAL if a socket has been shut down */
+            c->log_error = NGX_ERROR_IGNORE_EINVAL;
+#endif
+
+            ngx_connection_error(c, ngx_socket_errno,
+                                 "setsockopt(TCP_NODELAY) failed");
+
+            c->log_error = NGX_ERROR_INFO;
+            goto error;
+        }
+
+        c->tcp_nodelay = NGX_TCP_NODELAY_SET;
+    }
+
+    if (cl) {
+        ngx_add_timer(wev, clcf->send_timeout);
+
+    } else {
+        if (wev->timer_set) {
+            ngx_del_timer(wev);
+        }
+    }
+
+    for ( /* void */ ; out; out = fn) {
+        fn = out->next;
+
+        if (out->handler(h2c, out) != NGX_OK) {
+            out->blocked = 1;
+            break;
+        }
+
+        ngx_log_debug4(NGX_LOG_DEBUG_HTTP, c->log, 0,
+                       "http2 frame sent: %p sid:%ui bl:%d len:%uz",
+                       out, out->stream ? out->stream->node->id : 0,
+                       out->blocked, out->length);
+    }
+
+    frame = NULL;
+
+    for ( /* void */ ; out; out = fn) {
+        fn = out->next;
+        out->next = frame;
+        frame = out;
+    }
+
+    h2c->last_out = frame;
+
+    return NGX_OK;
+
+error:
+
+    c->error = 1;
+
+    if (!h2c->blocked) {
+        ngx_post_event(wev, &ngx_posted_events);
+    }
+
+    return NGX_ERROR;
+}
+
+
+static void
+ngx_http_v2_handle_connection(ngx_http_v2_connection_t *h2c)
+{
+    ngx_connection_t          *c;
+    ngx_http_v2_srv_conf_t  *h2scf;
+
+    if (h2c->last_out || h2c->processing) {
+        return;
+    }
+
+    c = h2c->connection;
+
+    if (c->error) {
+        ngx_http_close_connection(c);
+        return;
+    }
+
+    if (c->buffered) {
+        return;
+    }
+
+    h2scf = ngx_http_get_module_srv_conf(h2c->http_connection->conf_ctx,
+                                         ngx_http_v2_module);
+    if (h2c->state.incomplete) {
+        ngx_add_timer(c->read, h2scf->recv_timeout);
+        return;
+    }
+
+    if (ngx_terminate || ngx_exiting) {
+        ngx_http_close_connection(c);
+        return;
+    }
+
+    ngx_destroy_pool(h2c->pool);
+
+    h2c->pool = NULL;
+    h2c->free_frames = NULL;
+    h2c->free_fake_connections = NULL;
+
+#if (NGX_HTTP_SSL)
+    if (c->ssl) {
+        ngx_ssl_free_buffer(c);
+    }
+#endif
+
+    c->destroyed = 1;
+    c->idle = 1;
+    ngx_reusable_connection(c, 1);
+
+    c->write->handler = ngx_http_empty_handler;
+    c->read->handler = ngx_http_v2_idle_handler;
+
+    if (c->write->timer_set) {
+        ngx_del_timer(c->write);
+    }
+
+    ngx_add_timer(c->read, h2scf->idle_timeout);
+}
+
+
+static u_char *
+ngx_http_v2_state_proxy_protocol(ngx_http_v2_connection_t *h2c, u_char *pos,
+    u_char *end)
+{
+    ngx_log_t  *log;
+
+    log = h2c->connection->log;
+    log->action = "reading PROXY protocol";
+
+    pos = ngx_proxy_protocol_read(h2c->connection, pos, end);
+
+    log->action = "processing HTTP/2 connection";
+
+    if (pos == NULL) {
+        return ngx_http_v2_connection_error(h2c, NGX_HTTP_V2_PROTOCOL_ERROR);
+    }
+
+    return ngx_http_v2_state_preface(h2c, pos, end);
+}
+
+
+static u_char *
+ngx_http_v2_state_preface(ngx_http_v2_connection_t *h2c, u_char *pos,
+    u_char *end)
+{
+    static const u_char preface[] = "PRI * HTTP/2.0\r\n";
+
+    if ((size_t) (end - pos) < sizeof(preface) - 1) {
+        return ngx_http_v2_state_save(h2c, pos, end, ngx_http_v2_state_preface);
+    }
+
+    if (ngx_memcmp(pos, preface, sizeof(preface) - 1) != 0) {
+        ngx_log_debug2(NGX_LOG_DEBUG_HTTP, h2c->connection->log, 0,
+                       "invalid http2 connection preface \"%*s\"",
+                       sizeof(preface) - 1, pos);
+
+        return ngx_http_v2_connection_error(h2c, NGX_HTTP_V2_PROTOCOL_ERROR);
+    }
+
+    return ngx_http_v2_state_preface_end(h2c, pos + sizeof(preface) - 1, end);
+}
+
+
+static u_char *
+ngx_http_v2_state_preface_end(ngx_http_v2_connection_t *h2c, u_char *pos,
+    u_char *end)
+{
+    static const u_char preface[] = "\r\nSM\r\n\r\n";
+
+    if ((size_t) (end - pos) < sizeof(preface) - 1) {
+        return ngx_http_v2_state_save(h2c, pos, end,
+                                      ngx_http_v2_state_preface_end);
+    }
+
+    if (ngx_memcmp(pos, preface, sizeof(preface) - 1) != 0) {
+        ngx_log_debug2(NGX_LOG_DEBUG_HTTP, h2c->connection->log, 0,
+                       "invalid http2 connection preface \"%*s\"",
+                       sizeof(preface) - 1, pos);
+
+        return ngx_http_v2_connection_error(h2c, NGX_HTTP_V2_PROTOCOL_ERROR);
+    }
+
+    ngx_log_debug0(NGX_LOG_DEBUG_HTTP, h2c->connection->log, 0,
+                   "http2 preface verified");
+
+    return ngx_http_v2_state_head(h2c, pos + sizeof(preface) - 1, end);
+}
+
+
+static u_char *
+ngx_http_v2_state_head(ngx_http_v2_connection_t *h2c, u_char *pos, u_char *end)
+{
+    uint32_t    head;
+    ngx_uint_t  type;
+
+    if (end - pos < NGX_HTTP_V2_FRAME_HEADER_SIZE) {
+        return ngx_http_v2_state_save(h2c, pos, end, ngx_http_v2_state_head);
+    }
+
+    head = ngx_http_v2_parse_uint32(pos);
+
+    h2c->state.length = ngx_http_v2_parse_length(head);
+    h2c->state.flags = pos[4];
+
+    h2c->state.sid = ngx_http_v2_parse_sid(&pos[5]);
+
+    pos += NGX_HTTP_V2_FRAME_HEADER_SIZE;
+
+    type = ngx_http_v2_parse_type(head);
+
+    ngx_log_debug4(NGX_LOG_DEBUG_HTTP, h2c->connection->log, 0,
+                   "process http2 frame type:%ui f:%Xd l:%uz sid:%ui",
+                   type, h2c->state.flags, h2c->state.length, h2c->state.sid);
+
+    if (type >= NGX_HTTP_V2_FRAME_STATES) {
+        ngx_log_debug1(NGX_LOG_DEBUG_HTTP, h2c->connection->log, 0,
+                       "http2 frame with unknown type %ui", type);
+        return ngx_http_v2_state_skip(h2c, pos, end);
+    }
+
+    return ngx_http_v2_frame_states[type](h2c, pos, end);
+}
+
+
+static u_char *
+ngx_http_v2_state_data(ngx_http_v2_connection_t *h2c, u_char *pos, u_char *end)
+{
+    ngx_http_v2_node_t    *node;
+    ngx_http_v2_stream_t  *stream;
+
+    if (h2c->state.flags & NGX_HTTP_V2_PADDED_FLAG) {
+
+        if (h2c->state.length == 0) {
+            ngx_log_error(NGX_LOG_INFO, h2c->connection->log, 0,
+                          "client sent padded DATA frame "
+                          "with incorrect length: %uz",
+                          h2c->state.length);
+
+            return ngx_http_v2_connection_error(h2c, NGX_HTTP_V2_SIZE_ERROR);
+        }
+
+        if (end - pos == 0) {
+            return ngx_http_v2_state_save(h2c, pos, end,
+                                          ngx_http_v2_state_data);
+        }
+
+        h2c->state.padding = *pos++;
+        h2c->state.length--;
+
+        if (h2c->state.padding > h2c->state.length) {
+            ngx_log_error(NGX_LOG_INFO, h2c->connection->log, 0,
+                          "client sent padded DATA frame "
+                          "with incorrect length: %uz, padding: %uz",
+                          h2c->state.length, h2c->state.padding);
+
+            return ngx_http_v2_connection_error(h2c, NGX_HTTP_V2_SIZE_ERROR);
+        }
+
+        h2c->state.length -= h2c->state.padding;
+    }
+
+    ngx_log_debug0(NGX_LOG_DEBUG_HTTP, h2c->connection->log, 0,
+                   "http2 DATA frame");
+
+    if (h2c->state.length > h2c->recv_window) {
+        ngx_log_error(NGX_LOG_INFO, h2c->connection->log, 0,
+                      "client violated connection flow control: "
+                      "received DATA frame length %uz, available window %uz",
+                      h2c->state.length, h2c->recv_window);
+
+        return ngx_http_v2_connection_error(h2c, NGX_HTTP_V2_FLOW_CTRL_ERROR);
+    }
+
+    h2c->recv_window -= h2c->state.length;
+
+    if (h2c->recv_window < NGX_HTTP_V2_MAX_WINDOW / 4) {
+
+        if (ngx_http_v2_send_window_update(h2c, 0, NGX_HTTP_V2_MAX_WINDOW
+                                                   - h2c->recv_window)
+            == NGX_ERROR)
+        {
+            return ngx_http_v2_connection_error(h2c,
+                                                NGX_HTTP_V2_INTERNAL_ERROR);
+        }
+
+        h2c->recv_window = NGX_HTTP_V2_MAX_WINDOW;
+    }
+
+    node = ngx_http_v2_get_node_by_id(h2c, h2c->state.sid, 0);
+
+    if (node == NULL || node->stream == NULL) {
+        ngx_log_debug0(NGX_LOG_DEBUG_HTTP, h2c->connection->log, 0,
+                       "unknown http2 stream");
+
+        return ngx_http_v2_state_skip_padded(h2c, pos, end);
+    }
+
+    stream = node->stream;
+
+    if (h2c->state.length > stream->recv_window) {
+        ngx_log_error(NGX_LOG_INFO, h2c->connection->log, 0,
+                      "client violated flow control for stream %ui: "
+                      "received DATA frame length %uz, available window %uz",
+                      node->id, h2c->state.length, stream->recv_window);
+
+        if (ngx_http_v2_terminate_stream(h2c, stream,
+                                         NGX_HTTP_V2_FLOW_CTRL_ERROR)
+            == NGX_ERROR)
+        {
+            return ngx_http_v2_connection_error(h2c,
+                                                NGX_HTTP_V2_INTERNAL_ERROR);
+        }
+
+        return ngx_http_v2_state_skip_padded(h2c, pos, end);
+    }
+
+    stream->recv_window -= h2c->state.length;
+
+    if (stream->recv_window < NGX_HTTP_V2_MAX_WINDOW / 4) {
+
+        if (ngx_http_v2_send_window_update(h2c, node->id,
+                                           NGX_HTTP_V2_MAX_WINDOW
+                                           - stream->recv_window)
+            == NGX_ERROR)
+        {
+            return ngx_http_v2_connection_error(h2c,
+                                                NGX_HTTP_V2_INTERNAL_ERROR);
+        }
+
+        stream->recv_window = NGX_HTTP_V2_MAX_WINDOW;
+    }
+
+    if (stream->in_closed) {
+        ngx_log_error(NGX_LOG_INFO, h2c->connection->log, 0,
+                      "client sent DATA frame for half-closed stream %ui",
+                      node->id);
+
+        if (ngx_http_v2_terminate_stream(h2c, stream,
+                                         NGX_HTTP_V2_STREAM_CLOSED)
+            == NGX_ERROR)
+        {
+            return ngx_http_v2_connection_error(h2c,
+                                                NGX_HTTP_V2_INTERNAL_ERROR);
+        }
+
+        return ngx_http_v2_state_skip_padded(h2c, pos, end);
+    }
+
+    h2c->state.stream = stream;
+
+    return ngx_http_v2_state_read_data(h2c, pos, end);
+}
+
+
+static u_char *
+ngx_http_v2_state_read_data(ngx_http_v2_connection_t *h2c, u_char *pos,
+    u_char *end)
+{
+    size_t                     size;
+    ssize_t                    n;
+    ngx_buf_t                 *buf;
+    ngx_int_t                  rc;
+    ngx_temp_file_t           *tf;
+    ngx_http_request_t        *r;
+    ngx_http_v2_stream_t      *stream;
+    ngx_http_request_body_t   *rb;
+    ngx_http_core_loc_conf_t  *clcf;
+
+    stream = h2c->state.stream;
+
+    if (stream == NULL) {
+        return ngx_http_v2_state_skip_padded(h2c, pos, end);
+    }
+
+    if (stream->skip_data) {
+        stream->in_closed = h2c->state.flags & NGX_HTTP_V2_END_STREAM_FLAG;
+
+        ngx_log_debug1(NGX_LOG_DEBUG_HTTP, h2c->connection->log, 0,
+                       "skipping http2 DATA frame, reason: %d",
+                       stream->skip_data);
+
+        return ngx_http_v2_state_skip_padded(h2c, pos, end);
+    }
+
+    size = end - pos;
+
+    if (size > h2c->state.length) {
+        size = h2c->state.length;
+    }
+
+    r = stream->request;
+
+    if (r->request_body == NULL
+        && ngx_http_v2_init_request_body(r) != NGX_OK)
+    {
+        stream->skip_data = NGX_HTTP_V2_DATA_INTERNAL_ERROR;
+        return ngx_http_v2_state_skip_padded(h2c, pos, end);
+    }
+
+    rb = r->request_body;
+    tf = rb->temp_file;
+    buf = rb->buf;
+
+    if (size) {
+        rb->rest += size;
+
+        if (r->headers_in.content_length_n != -1
+            && r->headers_in.content_length_n < rb->rest)
+        {
+            ngx_log_error(NGX_LOG_INFO, r->connection->log, 0,
+                          "client intended to send body data "
+                          "larger than declared");
+
+            stream->skip_data = NGX_HTTP_V2_DATA_ERROR;
+            goto error;
+
+        } else {
+            clcf = ngx_http_get_module_loc_conf(r, ngx_http_core_module);
+
+            if (clcf->client_max_body_size
+                && clcf->client_max_body_size < rb->rest)
+            {
+                ngx_log_error(NGX_LOG_ERR, r->connection->log, 0,
+                              "client intended to send "
+                              "too large chunked body: %O bytes", rb->rest);
+
+                stream->skip_data = NGX_HTTP_V2_DATA_ERROR;
+                goto error;
+            }
+        }
+
+        h2c->state.length -= size;
+
+        if (tf) {
+            buf->start = pos;
+            buf->pos = pos;
+
+            pos += size;
+
+            buf->end = pos;
+            buf->last = pos;
+
+            n = ngx_write_chain_to_temp_file(tf, rb->bufs);
+
+            /* TODO: n == 0 or not complete and level event */
+
+            if (n == NGX_ERROR) {
+                stream->skip_data = NGX_HTTP_V2_DATA_INTERNAL_ERROR;
+                goto error;
+            }
+
+            tf->offset += n;
+
+        } else {
+            buf->last = ngx_cpymem(buf->last, pos, size);
+            pos += size;
+        }
+
+        r->request_length += size;
+    }
+
+    if (h2c->state.length) {
+        return ngx_http_v2_state_save(h2c, pos, end,
+                                      ngx_http_v2_state_read_data);
+    }
+
+    if (h2c->state.flags & NGX_HTTP_V2_END_STREAM_FLAG) {
+        stream->in_closed = 1;
+
+        if (r->headers_in.content_length_n < 0) {
+            r->headers_in.content_length_n = rb->rest;
+
+        } else if (r->headers_in.content_length_n != rb->rest) {
+            ngx_log_error(NGX_LOG_INFO, r->connection->log, 0,
+                          "client prematurely closed stream: "
+                          "only %O out of %O bytes of request body received",
+                          rb->rest, r->headers_in.content_length_n);
+
+            stream->skip_data = NGX_HTTP_V2_DATA_ERROR;
+            goto error;
+        }
+
+        if (tf) {
+            ngx_memzero(buf, sizeof(ngx_buf_t));
+
+            buf->in_file = 1;
+            buf->file_last = tf->file.offset;
+            buf->file = &tf->file;
+
+            rb->buf = NULL;
+        }
+
+        if (rb->post_handler) {
+            r->read_event_handler = ngx_http_block_reading;
+            rb->post_handler(r);
+        }
+    }
+
+    if (h2c->state.padding) {
+        return ngx_http_v2_state_skip_padded(h2c, pos, end);
+    }
+
+    return ngx_http_v2_state_complete(h2c, pos, end);
+
+error:
+
+    if (rb->post_handler) {
+
+        if (stream->skip_data == NGX_HTTP_V2_DATA_ERROR) {
+            rc = (r->headers_in.content_length_n == -1)
+                 ? NGX_HTTP_REQUEST_ENTITY_TOO_LARGE : NGX_HTTP_BAD_REQUEST;
+
+        } else {
+            rc = NGX_HTTP_INTERNAL_SERVER_ERROR;
+        }
+
+        ngx_http_finalize_request(r, rc);
+    }
+
+    return ngx_http_v2_state_skip_padded(h2c, pos, end);
+}
+
+
+static u_char *
+ngx_http_v2_state_headers(ngx_http_v2_connection_t *h2c, u_char *pos,
+    u_char *end)
+{
+    size_t                   size;
+    ngx_uint_t               padded, priority, depend, dependency, excl, weight;
+    ngx_http_v2_node_t      *node;
+    ngx_http_v2_stream_t    *stream;
+    ngx_http_v2_srv_conf_t  *h2scf;
+
+    padded = h2c->state.flags & NGX_HTTP_V2_PADDED_FLAG;
+    priority = h2c->state.flags & NGX_HTTP_V2_PRIORITY_FLAG;
+
+    size = 0;
+
+    if (padded) {
+        size++;
+    }
+
+    if (priority) {
+        size += sizeof(uint32_t) + 1;
+    }
+
+    if (h2c->state.length < size) {
+        ngx_log_error(NGX_LOG_INFO, h2c->connection->log, 0,
+                      "client sent HEADERS frame with incorrect length %uz",
+                      h2c->state.length);
+
+        return ngx_http_v2_connection_error(h2c, NGX_HTTP_V2_SIZE_ERROR);
+    }
+
+    if (h2c->state.length == size) {
+        ngx_log_error(NGX_LOG_INFO, h2c->connection->log, 0,
+                      "client sent HEADERS frame with empty header block");
+
+        return ngx_http_v2_connection_error(h2c, NGX_HTTP_V2_SIZE_ERROR);
+    }
+
+    if ((size_t) (end - pos) < size) {
+        return ngx_http_v2_state_save(h2c, pos, end,
+                                      ngx_http_v2_state_headers);
+    }
+
+    h2c->state.length -= size;
+
+    if (padded) {
+        h2c->state.padding = *pos++;
+
+        if (h2c->state.padding > h2c->state.length) {
+            ngx_log_error(NGX_LOG_INFO, h2c->connection->log, 0,
+                          "client sent padded HEADERS frame "
+                          "with incorrect length: %uz, padding: %uz",
+                          h2c->state.length, h2c->state.padding);
+
+            return ngx_http_v2_connection_error(h2c, NGX_HTTP_V2_SIZE_ERROR);
+        }
+
+        h2c->state.length -= h2c->state.padding;
+    }
+
+    depend = 0;
+    excl = 0;
+    weight = 16;
+
+    if (priority) {
+        dependency = ngx_http_v2_parse_uint32(pos);
+
+        depend = dependency & 0x7fffffff;
+        excl = dependency >> 31;
+        weight = pos[4] + 1;
+
+        pos += sizeof(uint32_t) + 1;
+    }
+
+    ngx_log_debug4(NGX_LOG_DEBUG_HTTP, h2c->connection->log, 0,
+                   "http2 HEADERS frame sid:%ui on %ui excl:%ui weight:%ui",
+                   h2c->state.sid, depend, excl, weight);
+
+    if (h2c->state.sid % 2 == 0 || h2c->state.sid <= h2c->last_sid) {
+        ngx_log_error(NGX_LOG_INFO, h2c->connection->log, 0,
+                      "client sent HEADERS frame with incorrect identifier "
+                      "%ui, the last was %ui", h2c->state.sid, h2c->last_sid);
+
+        return ngx_http_v2_connection_error(h2c, NGX_HTTP_V2_PROTOCOL_ERROR);
+    }
+
+    h2c->last_sid = h2c->state.sid;
+
+    h2scf = ngx_http_get_module_srv_conf(h2c->http_connection->conf_ctx,
+                                         ngx_http_v2_module);
+
+    h2c->state.header_limit = h2scf->max_header_size;
+
+    if (h2c->processing >= h2scf->concurrent_streams) {
+        ngx_log_error(NGX_LOG_INFO, h2c->connection->log, 0,
+                      "concurrent streams exceeded %ui", h2c->processing);
+
+        if (ngx_http_v2_send_rst_stream(h2c, h2c->state.sid,
+                                        NGX_HTTP_V2_REFUSED_STREAM)
+            != NGX_OK)
+        {
+            return ngx_http_v2_connection_error(h2c,
+                                                NGX_HTTP_V2_INTERNAL_ERROR);
+        }
+
+        return ngx_http_v2_state_skip_headers(h2c, pos, end);
+    }
+
+    node = ngx_http_v2_get_node_by_id(h2c, h2c->state.sid, 1);
+
+    if (node == NULL) {
+        return ngx_http_v2_connection_error(h2c, NGX_HTTP_V2_INTERNAL_ERROR);
+    }
+
+    if (node->parent) {
+        ngx_queue_remove(&node->reuse);
+        h2c->closed_nodes--;
+    }
+
+    stream = ngx_http_v2_create_stream(h2c);
+    if (stream == NULL) {
+        return ngx_http_v2_connection_error(h2c, NGX_HTTP_V2_INTERNAL_ERROR);
+    }
+
+    stream->in_closed = h2c->state.flags & NGX_HTTP_V2_END_STREAM_FLAG;
+    stream->node = node;
+
+    node->stream = stream;
+
+    h2c->state.stream = stream;
+    h2c->state.pool = stream->request->pool;
+
+    if (priority || node->parent == NULL) {
+        node->weight = weight;
+        ngx_http_v2_set_dependency(h2c, node, depend, excl);
+    }
+
+    return ngx_http_v2_state_header_block(h2c, pos, end);
+}
+
+
+static u_char *
+ngx_http_v2_state_header_block(ngx_http_v2_connection_t *h2c, u_char *pos,
+    u_char *end)
+{
+    u_char                   ch;
+    ngx_int_t                value;
+    ngx_uint_t               indexed, size_update, prefix;
+    ngx_http_v2_srv_conf_t  *h2scf;
+
+    if (end - pos < 1) {
+        return ngx_http_v2_state_save(h2c, pos, end,
+                                      ngx_http_v2_state_header_block);
+    }
+
+    size_update = 0;
+    indexed = 0;
+
+    ch = *pos;
+
+    if (ch >= (1 << 7)) {
+        /* indexed header field */
+        indexed = 1;
+        prefix = ngx_http_v2_prefix(7);
+
+    } else if (ch >= (1 << 6)) {
+        /* literal header field with incremental indexing */
+        h2c->state.index = 1;
+        prefix = ngx_http_v2_prefix(6);
+
+    } else if (ch >= (1 << 5)) {
+        /* dynamic table size update */
+        size_update = 1;
+        prefix = ngx_http_v2_prefix(5);
+
+    } else if (ch >= (1 << 4)) {
+        /* literal header field never indexed */
+        prefix = ngx_http_v2_prefix(4);
+
+    } else {
+        /* literal header field without indexing */
+        prefix = ngx_http_v2_prefix(3);
+    }
+
+    value = ngx_http_v2_parse_int(h2c, &pos, end, prefix);
+
+    if (value < 0) {
+        if (value == NGX_AGAIN) {
+            return ngx_http_v2_state_save(h2c, pos, end,
+                                          ngx_http_v2_state_header_block);
+        }
+
+        if (value == NGX_DECLINED) {
+            ngx_log_error(NGX_LOG_INFO, h2c->connection->log, 0,
+                          "client sent header block with too long %s value",
+                          size_update ? "size update" : "header index");
+
+            return ngx_http_v2_connection_error(h2c, NGX_HTTP_V2_COMP_ERROR);
+        }
+
+        ngx_log_error(NGX_LOG_INFO, h2c->connection->log, 0,
+                      "client sent header block with incorrect length");
+
+        return ngx_http_v2_connection_error(h2c, NGX_HTTP_V2_SIZE_ERROR);
+    }
+
+    if (indexed) {
+        if (ngx_http_v2_get_indexed_header(h2c, value, 0) != NGX_OK) {
+            return ngx_http_v2_connection_error(h2c, NGX_HTTP_V2_COMP_ERROR);
+        }
+
+        return ngx_http_v2_state_process_header(h2c, pos, end);
+    }
+
+    if (size_update) {
+        if (ngx_http_v2_table_size(h2c, value) != NGX_OK) {
+            return ngx_http_v2_connection_error(h2c, NGX_HTTP_V2_COMP_ERROR);
+        }
+
+        return ngx_http_v2_state_header_complete(h2c, pos, end);
+    }
+
+    h2scf = ngx_http_get_module_srv_conf(h2c->http_connection->conf_ctx,
+                                         ngx_http_v2_module);
+
+    h2c->state.field_limit = h2scf->max_field_size;
+
+    if (value == 0) {
+        h2c->state.parse_name = 1;
+
+    } else {
+        if (ngx_http_v2_get_indexed_header(h2c, value, 1) != NGX_OK) {
+            return ngx_http_v2_connection_error(h2c, NGX_HTTP_V2_COMP_ERROR);
+        }
+
+        h2c->state.field_limit -= h2c->state.header.name.len;
+    }
+
+    h2c->state.parse_value = 1;
+
+    return ngx_http_v2_state_field_len(h2c, pos, end);
+}
+
+
+static u_char *
+ngx_http_v2_state_field_len(ngx_http_v2_connection_t *h2c, u_char *pos,
+    u_char *end)
+{
+    size_t      alloc;
+    ngx_int_t   len;
+    ngx_uint_t  huff;
+
+    if (h2c->state.length < 1) {
+        ngx_log_error(NGX_LOG_INFO, h2c->connection->log, 0,
+                      "client sent header block with incorrect length");
+
+        return ngx_http_v2_connection_error(h2c, NGX_HTTP_V2_SIZE_ERROR);
+    }
+
+    if (end - pos < 1) {
+        return ngx_http_v2_state_save(h2c, pos, end,
+                                      ngx_http_v2_state_field_len);
+    }
+
+    huff = *pos >> 7;
+    len = ngx_http_v2_parse_int(h2c, &pos, end, ngx_http_v2_prefix(7));
+
+    if (len < 0) {
+        if (len == NGX_AGAIN) {
+            return ngx_http_v2_state_save(h2c, pos, end,
+                                          ngx_http_v2_state_field_len);
+        }
+
+        if (len == NGX_DECLINED) {
+            ngx_log_error(NGX_LOG_INFO, h2c->connection->log, 0,
+                        "client sent header field with too long length value");
+
+            return ngx_http_v2_connection_error(h2c, NGX_HTTP_V2_COMP_ERROR);
+        }
+
+        ngx_log_error(NGX_LOG_INFO, h2c->connection->log, 0,
+                      "client sent header block with incorrect length");
+
+        return ngx_http_v2_connection_error(h2c, NGX_HTTP_V2_SIZE_ERROR);
+    }
+
+    ngx_log_debug2(NGX_LOG_DEBUG_HTTP, h2c->connection->log, 0,
+                   "http2 hpack %s string length: %i",
+                   huff ? "encoded" : "raw", len);
+
+    if ((size_t) len > h2c->state.length) {
+        ngx_log_error(NGX_LOG_INFO, h2c->connection->log, 0,
+                      "client sent header field with incorrect length");
+
+        return ngx_http_v2_connection_error(h2c, NGX_HTTP_V2_SIZE_ERROR);
+    }
+
+    h2c->state.length -= len;
+
+    if ((size_t) len > h2c->state.field_limit) {
+        ngx_log_error(NGX_LOG_INFO, h2c->connection->log, 0,
+                      "client exceeded http2_max_field_size limit");
+
+        return ngx_http_v2_connection_error(h2c, NGX_HTTP_V2_ENHANCE_YOUR_CALM);
+    }
+
+    h2c->state.field_limit -= len;
+    h2c->state.field_rest = len;
+
+    if (h2c->state.stream == NULL && !h2c->state.index) {
+        return ngx_http_v2_state_field_skip(h2c, pos, end);
+    }
+
+    alloc = (huff ? len * 8 / 5 : len) + 1;
+
+    h2c->state.field_start = ngx_pnalloc(h2c->state.pool, alloc);
+    if (h2c->state.field_start == NULL) {
+        return ngx_http_v2_connection_error(h2c, NGX_HTTP_V2_INTERNAL_ERROR);
+    }
+
+    h2c->state.field_end = h2c->state.field_start;
+
+    if (huff) {
+        return ngx_http_v2_state_field_huff(h2c, pos, end);
+    }
+
+    return ngx_http_v2_state_field_raw(h2c, pos, end);
+}
+
+
+static u_char *
+ngx_http_v2_state_field_huff(ngx_http_v2_connection_t *h2c, u_char *pos,
+    u_char *end)
+{
+    size_t  size;
+
+    size = end - pos;
+
+    if (size > h2c->state.field_rest) {
+        size = h2c->state.field_rest;
+    }
+
+    h2c->state.field_rest -= size;
+
+    if (ngx_http_v2_huff_decode(&h2c->state.field_state, pos, size,
+                                &h2c->state.field_end,
+                                h2c->state.field_rest == 0,
+                                h2c->connection->log)
+        != NGX_OK)
+    {
+        ngx_log_error(NGX_LOG_INFO, h2c->connection->log, 0,
+                      "client sent invalid encoded header field");
+
+        return ngx_http_v2_connection_error(h2c, NGX_HTTP_V2_COMP_ERROR);
+    }
+
+    if (h2c->state.field_rest != 0) {
+        return ngx_http_v2_state_save(h2c, end, end,
+                                      ngx_http_v2_state_field_huff);
+    }
+
+    *h2c->state.field_end = '\0';
+
+    return ngx_http_v2_state_process_header(h2c, pos + size, end);
+}
+
+
+static u_char *
+ngx_http_v2_state_field_raw(ngx_http_v2_connection_t *h2c, u_char *pos,
+    u_char *end)
+{
+    size_t  size;
+
+    size = end - pos;
+
+    if (size > h2c->state.field_rest) {
+        size = h2c->state.field_rest;
+    }
+
+    h2c->state.field_rest -= size;
+
+    h2c->state.field_end = ngx_cpymem(h2c->state.field_end, pos, size);
+
+    if (h2c->state.field_rest) {
+        return ngx_http_v2_state_save(h2c, end, end,
+                                      ngx_http_v2_state_field_raw);
+    }
+
+    *h2c->state.field_end = '\0';
+
+    return ngx_http_v2_state_process_header(h2c, pos + size, end);
+}
+
+
+static u_char *
+ngx_http_v2_state_field_skip(ngx_http_v2_connection_t *h2c, u_char *pos,
+    u_char *end)
+{
+    size_t  size;
+
+    size = end - pos;
+
+    if (size > h2c->state.field_rest) {
+        size = h2c->state.field_rest;
+    }
+
+    h2c->state.field_rest -= size;
+
+    return ngx_http_v2_state_process_header(h2c, pos + size, end);
+}
+
+
+static u_char *
+ngx_http_v2_state_process_header(ngx_http_v2_connection_t *h2c, u_char *pos,
+    u_char *end)
+{
+    size_t                      len;
+    ngx_int_t                   rc;
+    ngx_table_elt_t            *h;
+    ngx_http_header_t          *hh;
+    ngx_http_request_t         *r;
+    ngx_http_v2_header_t       *header;
+    ngx_http_core_srv_conf_t   *cscf;
+    ngx_http_core_main_conf_t  *cmcf;
+
+    static ngx_str_t cookie = ngx_string("cookie");
+
+    header = &h2c->state.header;
+
+    if (h2c->state.parse_name) {
+        h2c->state.parse_name = 0;
+
+        header->name.len = h2c->state.field_end - h2c->state.field_start;
+        header->name.data = h2c->state.field_start;
+
+        return ngx_http_v2_state_field_len(h2c, pos, end);
+    }
+
+    if (h2c->state.parse_value) {
+        h2c->state.parse_value = 0;
+
+        header->value.len = h2c->state.field_end - h2c->state.field_start;
+        header->value.data = h2c->state.field_start;
+    }
+
+    len = header->name.len + header->value.len;
+
+    if (len > h2c->state.header_limit) {
+        ngx_log_error(NGX_LOG_INFO, h2c->connection->log, 0,
+                      "client exceeded http2_max_header_size limit");
+
+        return ngx_http_v2_connection_error(h2c, NGX_HTTP_V2_ENHANCE_YOUR_CALM);
+    }
+
+    h2c->state.header_limit -= len;
+
+    if (h2c->state.index) {
+        if (ngx_http_v2_add_header(h2c, header) != NGX_OK) {
+            return ngx_http_v2_connection_error(h2c,
+                                                NGX_HTTP_V2_INTERNAL_ERROR);
+        }
+
+        h2c->state.index = 0;
+    }
+
+    if (h2c->state.stream == NULL) {
+        return ngx_http_v2_state_header_complete(h2c, pos, end);
+    }
+
+    r = h2c->state.stream->request;
+
+    /* TODO Optimization: validate headers while parsing. */
+    if (ngx_http_v2_validate_header(r, header) != NGX_OK) {
+        if (ngx_http_v2_terminate_stream(h2c, h2c->state.stream,
+                                         NGX_HTTP_V2_PROTOCOL_ERROR)
+            == NGX_ERROR)
+        {
+            return ngx_http_v2_connection_error(h2c,
+                                                NGX_HTTP_V2_INTERNAL_ERROR);
+        }
+
+        goto error;
+    }
+
+    if (header->name.data[0] == ':') {
+        rc = ngx_http_v2_pseudo_header(r, header);
+
+        if (rc == NGX_OK) {
+            return ngx_http_v2_state_header_complete(h2c, pos, end);
+        }
+
+        if (rc == NGX_ABORT) {
+            goto error;
+        }
+
+        if (rc == NGX_DECLINED) {
+            if (ngx_http_v2_terminate_stream(h2c, h2c->state.stream,
+                                             NGX_HTTP_V2_PROTOCOL_ERROR)
+                == NGX_ERROR)
+            {
+                return ngx_http_v2_connection_error(h2c,
+                                                    NGX_HTTP_V2_INTERNAL_ERROR);
+            }
+
+            goto error;
+        }
+
+        return ngx_http_v2_connection_error(h2c, NGX_HTTP_V2_INTERNAL_ERROR);
+    }
+
+    if (r->invalid_header) {
+        cscf = ngx_http_get_module_srv_conf(r, ngx_http_core_module);
+
+        if (cscf->ignore_invalid_headers) {
+            ngx_log_error(NGX_LOG_INFO, r->connection->log, 0,
+                          "client sent invalid header: \"%V\"", &header->name);
+
+            return ngx_http_v2_state_header_complete(h2c, pos, end);
+        }
+    }
+
+    if (header->name.len == cookie.len
+        && ngx_memcmp(header->name.data, cookie.data, cookie.len) == 0)
+    {
+        if (ngx_http_v2_cookie(r, header) != NGX_OK) {
+            return ngx_http_v2_connection_error(h2c,
+                                                NGX_HTTP_V2_INTERNAL_ERROR);
+        }
+
+        return ngx_http_v2_state_header_complete(h2c, pos, end);
+    }
+
+    h = ngx_list_push(&r->headers_in.headers);
+    if (h == NULL) {
+        return ngx_http_v2_connection_error(h2c, NGX_HTTP_V2_INTERNAL_ERROR);
+    }
+
+    h->key.len = header->name.len;
+    h->key.data = header->name.data;
+
+    /* TODO Optimization: precalculate hash and hadnler for indexed headers. */
+    h->hash = ngx_hash_key(h->key.data, h->key.len);
+
+    h->value.len = header->value.len;
+    h->value.data = header->value.data;
+
+    h->lowcase_key = h->key.data;
+
+    cmcf = ngx_http_get_module_main_conf(r, ngx_http_core_module);
+
+    hh = ngx_hash_find(&cmcf->headers_in_hash, h->hash,
+                       h->lowcase_key, h->key.len);
+
+    if (hh && hh->handler(r, h, hh->offset) != NGX_OK) {
+        goto error;
+    }
+
+    ngx_log_debug2(NGX_LOG_DEBUG_HTTP, r->connection->log, 0,
+                   "http2 http header: \"%V: %V\"", &h->key, &h->value);
+
+    return ngx_http_v2_state_header_complete(h2c, pos, end);
+
+error:
+
+    h2c->state.stream = NULL;
+    h2c->state.pool = NULL;
+
+    return ngx_http_v2_state_header_complete(h2c, pos, end);
+}
+
+
+static u_char *
+ngx_http_v2_state_header_complete(ngx_http_v2_connection_t *h2c, u_char *pos,
+    u_char *end)
+{
+    ngx_http_v2_stream_t  *stream;
+
+    if (h2c->state.length) {
+        h2c->state.handler = h2c->state.pool ? ngx_http_v2_state_header_block
+                                             : ngx_http_v2_state_skip_headers;
+        return pos;
+    }
+
+    stream = h2c->state.stream;
+
+    if (stream) {
+        if (h2c->state.flags & NGX_HTTP_V2_END_HEADERS_FLAG) {
+            stream->end_headers = 1;
+            ngx_http_v2_run_request(stream->request);
+
+        } else {
+            stream->header_limit = h2c->state.header_limit;
+        }
+
+    } else if (h2c->state.pool) {
+        ngx_destroy_pool(h2c->state.pool);
+    }
+
+    h2c->state.pool = NULL;
+
+    if (h2c->state.padding) {
+        return ngx_http_v2_state_skip_padded(h2c, pos, end);
+    }
+
+    return ngx_http_v2_state_complete(h2c, pos, end);
+}
+
+
+static u_char *
+ngx_http_v2_state_priority(ngx_http_v2_connection_t *h2c, u_char *pos,
+    u_char *end)
+{
+    ngx_uint_t           depend, dependency, excl, weight;
+    ngx_http_v2_node_t  *node;
+
+    if (h2c->state.length != NGX_HTTP_V2_PRIORITY_SIZE) {
+        ngx_log_error(NGX_LOG_INFO, h2c->connection->log, 0,
+                      "client sent PRIORITY frame with incorrect length %uz",
+                      h2c->state.length);
+
+        return ngx_http_v2_connection_error(h2c, NGX_HTTP_V2_SIZE_ERROR);
+    }
+
+    if (end - pos < NGX_HTTP_V2_PRIORITY_SIZE) {
+        return ngx_http_v2_state_save(h2c, pos, end,
+                                      ngx_http_v2_state_priority);
+    }
+
+    dependency = ngx_http_v2_parse_uint32(pos);
+
+    depend = dependency & 0x7fffffff;
+    excl = dependency >> 31;
+    weight = pos[4] + 1;
+
+    pos += NGX_HTTP_V2_PRIORITY_SIZE;
+
+    ngx_log_debug4(NGX_LOG_DEBUG_HTTP, h2c->connection->log, 0,
+                   "http2 PRIORITY frame sid:%ui on %ui excl:%ui weight:%ui",
+                   h2c->state.sid, depend, excl, weight);
+
+    if (h2c->state.sid == 0) {
+        ngx_log_error(NGX_LOG_INFO, h2c->connection->log, 0,
+                      "client sent PRIORITY frame with incorrect identifier");
+
+        return ngx_http_v2_connection_error(h2c, NGX_HTTP_V2_PROTOCOL_ERROR);
+    }
+
+    if (depend == h2c->state.sid) {
+        ngx_log_error(NGX_LOG_INFO, h2c->connection->log, 0,
+                      "client sent PRIORITY frame for stream %ui "
+                      "with incorrect dependancy", h2c->state.sid);
+
+        node = ngx_http_v2_get_node_by_id(h2c, h2c->state.sid, 0);
+
+        if (node && node->stream) {
+            if (ngx_http_v2_terminate_stream(h2c, node->stream,
+                                             NGX_HTTP_V2_PROTOCOL_ERROR)
+                == NGX_ERROR)
+            {
+                return ngx_http_v2_connection_error(h2c,
+                                                    NGX_HTTP_V2_INTERNAL_ERROR);
+            }
+
+        } else {
+            if (ngx_http_v2_send_rst_stream(h2c, h2c->state.sid,
+                                            NGX_HTTP_V2_PROTOCOL_ERROR)
+                == NGX_ERROR)
+            {
+                return ngx_http_v2_connection_error(h2c,
+                                                    NGX_HTTP_V2_INTERNAL_ERROR);
+            }
+        }
+
+        return ngx_http_v2_state_complete(h2c, pos, end);
+    }
+
+    node = ngx_http_v2_get_node_by_id(h2c, h2c->state.sid, 1);
+
+    if (node == NULL) {
+        return ngx_http_v2_connection_error(h2c, NGX_HTTP_V2_INTERNAL_ERROR);
+    }
+
+    node->weight = weight;
+
+    if (node->stream == NULL) {
+        if (node->parent == NULL) {
+            h2c->closed_nodes++;
+
+        } else {
+            ngx_queue_remove(&node->reuse);
+        }
+
+        ngx_queue_insert_tail(&h2c->closed, &node->reuse);
+    }
+
+    ngx_http_v2_set_dependency(h2c, node, depend, excl);
+
+    return ngx_http_v2_state_complete(h2c, pos, end);
+}
+
+
+static u_char *
+ngx_http_v2_state_rst_stream(ngx_http_v2_connection_t *h2c, u_char *pos,
+    u_char *end)
+{
+    ngx_uint_t             status;
+    ngx_event_t           *ev;
+    ngx_connection_t      *fc;
+    ngx_http_v2_node_t    *node;
+    ngx_http_v2_stream_t  *stream;
+
+    if (h2c->state.length != NGX_HTTP_V2_RST_STREAM_SIZE) {
+        ngx_log_error(NGX_LOG_INFO, h2c->connection->log, 0,
+                      "client sent RST_STREAM frame with incorrect length %uz",
+                      h2c->state.length);
+
+        return ngx_http_v2_connection_error(h2c, NGX_HTTP_V2_SIZE_ERROR);
+    }
+
+    if (end - pos < NGX_HTTP_V2_RST_STREAM_SIZE) {
+        return ngx_http_v2_state_save(h2c, pos, end,
+                                      ngx_http_v2_state_rst_stream);
+    }
+
+    status = ngx_http_v2_parse_uint32(pos);
+
+    pos += NGX_HTTP_V2_RST_STREAM_SIZE;
+
+    ngx_log_debug2(NGX_LOG_DEBUG_HTTP, h2c->connection->log, 0,
+                   "http2 RST_STREAM frame, sid:%ui status:%ui",
+                   h2c->state.sid, status);
+
+    if (h2c->state.sid == 0) {
+        ngx_log_error(NGX_LOG_INFO, h2c->connection->log, 0,
+                      "client sent RST_STREAM frame with incorrect identifier");
+
+        return ngx_http_v2_connection_error(h2c, NGX_HTTP_V2_PROTOCOL_ERROR);
+    }
+
+    node = ngx_http_v2_get_node_by_id(h2c, h2c->state.sid, 0);
+
+    if (node == NULL || node->stream == NULL) {
+        ngx_log_debug0(NGX_LOG_DEBUG_HTTP, h2c->connection->log, 0,
+                        "unknown http2 stream");
+
+        return ngx_http_v2_state_complete(h2c, pos, end);
+    }
+
+    stream = node->stream;
+
+    stream->in_closed = 1;
+    stream->out_closed = 1;
+
+    fc = stream->request->connection;
+    fc->error = 1;
+
+    switch (status) {
+
+    case NGX_HTTP_V2_CANCEL:
+        ngx_log_error(NGX_LOG_INFO, fc->log, 0,
+                      "client canceled stream %ui", h2c->state.sid);
+        break;
+
+    case NGX_HTTP_V2_INTERNAL_ERROR:
+        ngx_log_error(NGX_LOG_INFO, fc->log, 0,
+                      "client terminated stream %ui due to internal error",
+                      h2c->state.sid);
+        break;
+
+    default:
+        ngx_log_error(NGX_LOG_INFO, fc->log, 0,
+                      "client terminated stream %ui with status %ui",
+                      h2c->state.sid, status);
+        break;
+    }
+
+    ev = fc->read;
+    ev->handler(ev);
+
+    return ngx_http_v2_state_complete(h2c, pos, end);
+}
+
+
+static u_char *
+ngx_http_v2_state_settings(ngx_http_v2_connection_t *h2c, u_char *pos,
+    u_char *end)
+{
+    if (h2c->state.flags == NGX_HTTP_V2_ACK_FLAG) {
+
+        if (h2c->state.length != 0) {
+            ngx_log_error(NGX_LOG_INFO, h2c->connection->log, 0,
+                          "client sent SETTINGS frame with the ACK flag "
+                          "and nonzero length");
+
+            return ngx_http_v2_connection_error(h2c, NGX_HTTP_V2_SIZE_ERROR);
+        }
+
+        /* TODO settings acknowledged */
+
+        return ngx_http_v2_state_complete(h2c, pos, end);
+    }
+
+    if (h2c->state.length % NGX_HTTP_V2_SETTINGS_PARAM_SIZE) {
+        ngx_log_error(NGX_LOG_INFO, h2c->connection->log, 0,
+                      "client sent SETTINGS frame with incorrect length %uz",
+                      h2c->state.length);
+
+        return ngx_http_v2_connection_error(h2c, NGX_HTTP_V2_SIZE_ERROR);
+    }
+
+    ngx_http_v2_send_settings(h2c, 1);
+
+    return ngx_http_v2_state_settings_params(h2c, pos, end);
+}
+
+
+static u_char *
+ngx_http_v2_state_settings_params(ngx_http_v2_connection_t *h2c, u_char *pos,
+    u_char *end)
+{
+    ngx_uint_t  id, value;
+
+    while (h2c->state.length) {
+        if (end - pos < NGX_HTTP_V2_SETTINGS_PARAM_SIZE) {
+            return ngx_http_v2_state_save(h2c, pos, end,
+                                          ngx_http_v2_state_settings_params);
+        }
+
+        h2c->state.length -= NGX_HTTP_V2_SETTINGS_PARAM_SIZE;
+
+        id = ngx_http_v2_parse_uint16(pos);
+        value = ngx_http_v2_parse_uint32(&pos[2]);
+
+        switch (id) {
+
+        case NGX_HTTP_V2_INIT_WINDOW_SIZE_SETTING:
+
+            if (value > NGX_HTTP_V2_MAX_WINDOW) {
+                ngx_log_error(NGX_LOG_INFO, h2c->connection->log, 0,
+                              "client sent SETTINGS frame with incorrect "
+                              "INITIAL_WINDOW_SIZE value %ui", value);
+
+                return ngx_http_v2_connection_error(h2c,
+                                                  NGX_HTTP_V2_FLOW_CTRL_ERROR);
+            }
+
+            if (ngx_http_v2_adjust_windows(h2c, value - h2c->init_window)
+                != NGX_OK)
+            {
+                return ngx_http_v2_connection_error(h2c,
+                                                    NGX_HTTP_V2_INTERNAL_ERROR);
+            }
+
+            h2c->init_window = value;
+            break;
+
+        case NGX_HTTP_V2_MAX_FRAME_SIZE_SETTING:
+            if (value > NGX_HTTP_V2_MAX_FRAME_SIZE
+                || value < NGX_HTTP_V2_DEFAULT_FRAME_SIZE)
+            {
+                ngx_log_error(NGX_LOG_INFO, h2c->connection->log, 0,
+                              "client sent SETTINGS frame with incorrect "
+                              "MAX_FRAME_SIZE value %ui", value);
+
+                return ngx_http_v2_connection_error(h2c,
+                                                    NGX_HTTP_V2_PROTOCOL_ERROR);
+            }
+
+            h2c->frame_size = value;
+            break;
+
+        default:
+            break;
+        }
+
+        pos += NGX_HTTP_V2_SETTINGS_PARAM_SIZE;
+    }
+
+    return ngx_http_v2_state_complete(h2c, pos, end);
+}
+
+
+static u_char *
+ngx_http_v2_state_push_promise(ngx_http_v2_connection_t *h2c, u_char *pos,
+    u_char *end)
+{
+    ngx_log_error(NGX_LOG_INFO, h2c->connection->log, 0,
+                  "client sent PUSH_PROMISE frame");
+
+    return ngx_http_v2_connection_error(h2c, NGX_HTTP_V2_PROTOCOL_ERROR);
+}
+
+
+static u_char *
+ngx_http_v2_state_ping(ngx_http_v2_connection_t *h2c, u_char *pos, u_char *end)
+{
+    ngx_buf_t                *buf;
+    ngx_http_v2_out_frame_t  *frame;
+
+    if (h2c->state.length != NGX_HTTP_V2_PING_SIZE) {
+        ngx_log_error(NGX_LOG_INFO, h2c->connection->log, 0,
+                      "client sent PING frame with incorrect length %uz",
+                      h2c->state.length);
+
+        return ngx_http_v2_connection_error(h2c, NGX_HTTP_V2_SIZE_ERROR);
+    }
+
+    if (end - pos < NGX_HTTP_V2_PING_SIZE) {
+        return ngx_http_v2_state_save(h2c, pos, end, ngx_http_v2_state_ping);
+    }
+
+    ngx_log_debug1(NGX_LOG_DEBUG_HTTP, h2c->connection->log, 0,
+                   "http2 PING frame, flags: %ui", h2c->state.flags);
+
+    if (h2c->state.flags & NGX_HTTP_V2_ACK_FLAG) {
+        return ngx_http_v2_state_skip(h2c, pos, end);
+    }
+
+    frame = ngx_http_v2_get_frame(h2c, NGX_HTTP_V2_PING_SIZE,
+                                  NGX_HTTP_V2_PING_FRAME,
+                                  NGX_HTTP_V2_ACK_FLAG, 0);
+    if (frame == NULL) {
+        return ngx_http_v2_connection_error(h2c, NGX_HTTP_V2_INTERNAL_ERROR);
+    }
+
+    buf = frame->first->buf;
+
+    buf->last = ngx_cpymem(buf->last, pos, NGX_HTTP_V2_PING_SIZE);
+
+    ngx_http_v2_queue_blocked_frame(h2c, frame);
+
+    return ngx_http_v2_state_complete(h2c, pos + NGX_HTTP_V2_PING_SIZE, end);
+}
+
+
+static u_char *
+ngx_http_v2_state_goaway(ngx_http_v2_connection_t *h2c, u_char *pos,
+    u_char *end)
+{
+#if (NGX_DEBUG)
+    ngx_uint_t  last_sid, error;
+#endif
+
+    if (h2c->state.length < NGX_HTTP_V2_GOAWAY_SIZE) {
+        ngx_log_error(NGX_LOG_INFO, h2c->connection->log, 0,
+                      "client sent GOAWAY frame "
+                      "with incorrect length %uz", h2c->state.length);
+
+        return ngx_http_v2_connection_error(h2c, NGX_HTTP_V2_SIZE_ERROR);
+    }
+
+    if (end - pos < NGX_HTTP_V2_GOAWAY_SIZE) {
+        return ngx_http_v2_state_save(h2c, pos, end, ngx_http_v2_state_goaway);
+    }
+
+#if (NGX_DEBUG)
+    h2c->state.length -= NGX_HTTP_V2_GOAWAY_SIZE;
+
+    last_sid = ngx_http_v2_parse_sid(pos);
+    error = ngx_http_v2_parse_uint32(&pos[4]);
+
+    pos += NGX_HTTP_V2_GOAWAY_SIZE;
+
+    ngx_log_debug2(NGX_LOG_DEBUG_HTTP, h2c->connection->log, 0,
+                   "http2 GOAWAY frame: last sid %ui, error %ui",
+                   last_sid, error);
+#endif
+
+    return ngx_http_v2_state_skip(h2c, pos, end);
+}
+
+
+static u_char *
+ngx_http_v2_state_window_update(ngx_http_v2_connection_t *h2c, u_char *pos,
+    u_char *end)
+{
+    size_t                 window;
+    ngx_event_t           *wev;
+    ngx_queue_t           *q;
+    ngx_http_v2_node_t    *node;
+    ngx_http_v2_stream_t  *stream;
+
+    if (h2c->state.length != NGX_HTTP_V2_WINDOW_UPDATE_SIZE) {
+        ngx_log_error(NGX_LOG_INFO, h2c->connection->log, 0,
+                      "client sent WINDOW_UPDATE frame "
+                      "with incorrect length %uz", h2c->state.length);
+
+        return ngx_http_v2_connection_error(h2c, NGX_HTTP_V2_SIZE_ERROR);
+    }
+
+    if (end - pos < NGX_HTTP_V2_WINDOW_UPDATE_SIZE) {
+        return ngx_http_v2_state_save(h2c, pos, end,
+                                      ngx_http_v2_state_window_update);
+    }
+
+    window = ngx_http_v2_parse_window(pos);
+
+    pos += NGX_HTTP_V2_WINDOW_UPDATE_SIZE;
+
+    ngx_log_debug2(NGX_LOG_DEBUG_HTTP, h2c->connection->log, 0,
+                   "http2 WINDOW_UPDATE frame sid:%ui window:%uz",
+                   h2c->state.sid, window);
+
+    if (h2c->state.sid) {
+        node = ngx_http_v2_get_node_by_id(h2c, h2c->state.sid, 0);
+
+        if (node == NULL || node->stream == NULL) {
+            ngx_log_debug0(NGX_LOG_DEBUG_HTTP, h2c->connection->log, 0,
+                           "unknown http2 stream");
+
+            return ngx_http_v2_state_complete(h2c, pos, end);
+        }
+
+        stream = node->stream;
+
+        if (window > (size_t) (NGX_HTTP_V2_MAX_WINDOW - stream->send_window)) {
+
+            ngx_log_error(NGX_LOG_INFO, h2c->connection->log, 0,
+                          "client violated flow control for stream %ui: "
+                          "received WINDOW_UPDATE frame "
+                          "with window increment %uz "
+                          "not allowed for window %z",
+                          h2c->state.sid, window, stream->send_window);
+
+            if (ngx_http_v2_terminate_stream(h2c, stream,
+                                             NGX_HTTP_V2_FLOW_CTRL_ERROR)
+                == NGX_ERROR)
+            {
+                return ngx_http_v2_connection_error(h2c,
+                                                    NGX_HTTP_V2_INTERNAL_ERROR);
+            }
+
+            return ngx_http_v2_state_complete(h2c, pos, end);
+        }
+
+        stream->send_window += window;
+
+        if (stream->exhausted) {
+            stream->exhausted = 0;
+
+            wev = stream->request->connection->write;
+
+            if (!wev->timer_set) {
+                wev->delayed = 0;
+                wev->handler(wev);
+            }
+        }
+
+        return ngx_http_v2_state_complete(h2c, pos, end);
+    }
+
+    if (window > NGX_HTTP_V2_MAX_WINDOW - h2c->send_window) {
+        ngx_log_error(NGX_LOG_INFO, h2c->connection->log, 0,
+                      "client violated connection flow control: "
+                      "received WINDOW_UPDATE frame "
+                      "with window increment %uz "
+                      "not allowed for window %uz",
+                      window, h2c->send_window);
+
+        return ngx_http_v2_connection_error(h2c, NGX_HTTP_V2_FLOW_CTRL_ERROR);
+    }
+
+    h2c->send_window += window;
+
+    while (!ngx_queue_empty(&h2c->waiting)) {
+        q = ngx_queue_head(&h2c->waiting);
+
+        ngx_queue_remove(q);
+
+        stream = ngx_queue_data(q, ngx_http_v2_stream_t, queue);
+
+        stream->handled = 0;
+
+        wev = stream->request->connection->write;
+
+        if (!wev->timer_set) {
+            wev->delayed = 0;
+            wev->handler(wev);
+
+            if (h2c->send_window == 0) {
+                break;
+            }
+        }
+    }
+
+    return ngx_http_v2_state_complete(h2c, pos, end);
+}
+
+
+static u_char *
+ngx_http_v2_state_continuation(ngx_http_v2_connection_t *h2c, u_char *pos,
+    u_char *end)
+{
+    ngx_http_v2_node_t      *node;
+    ngx_http_v2_stream_t    *stream;
+    ngx_http_v2_srv_conf_t  *h2scf;
+
+    if (h2c->state.length == 0) {
+        ngx_log_error(NGX_LOG_INFO, h2c->connection->log, 0,
+                      "client sent CONTINUATION with empty header block");
+
+        return ngx_http_v2_connection_error(h2c, NGX_HTTP_V2_SIZE_ERROR);
+    }
+
+    if (h2c->state.sid == 0) {
+        ngx_log_error(NGX_LOG_INFO, h2c->connection->log, 0,
+                   "client sent CONTINUATION frame with incorrect identifier");
+
+        return ngx_http_v2_connection_error(h2c, NGX_HTTP_V2_PROTOCOL_ERROR);
+    }
+
+    node = ngx_http_v2_get_node_by_id(h2c, h2c->state.sid, 0);
+
+    if (node == NULL || node->stream == NULL) {
+        h2scf = ngx_http_get_module_srv_conf(h2c->http_connection->conf_ctx,
+                                             ngx_http_v2_module);
+
+        h2c->state.header_limit = h2scf->max_header_size;
+
+        return ngx_http_v2_state_skip_headers(h2c, pos, end);
+    }
+
+    stream = node->stream;
+
+    if (stream->end_headers) {
+        ngx_log_error(NGX_LOG_INFO, h2c->connection->log, 0,
+                      "client sent unexpected CONTINUATION frame");
+
+        return ngx_http_v2_connection_error(h2c, NGX_HTTP_V2_PROTOCOL_ERROR);
+    }
+
+    h2c->state.stream = stream;
+    h2c->state.header_limit = stream->header_limit;
+    h2c->state.pool = stream->request->pool;
+
+    return ngx_http_v2_state_header_block(h2c, pos, end);
+}
+
+
+static u_char *
+ngx_http_v2_state_complete(ngx_http_v2_connection_t *h2c, u_char *pos,
+    u_char *end)
+{
+    ngx_log_debug2(NGX_LOG_DEBUG_HTTP, h2c->connection->log, 0,
+                   "http2 frame complete pos:%p end:%p", pos, end);
+
+    if (pos > end) {
+        ngx_log_error(NGX_LOG_ALERT, h2c->connection->log, 0,
+                      "receive buffer overrun");
+
+        return ngx_http_v2_connection_error(h2c, NGX_HTTP_V2_INTERNAL_ERROR);
+    }
+
+    h2c->state.stream = NULL;
+    h2c->state.handler = ngx_http_v2_state_head;
+
+    return pos;
+}
+
+
+static u_char *
+ngx_http_v2_state_skip_padded(ngx_http_v2_connection_t *h2c, u_char *pos,
+    u_char *end)
+{
+    h2c->state.length += h2c->state.padding;
+    h2c->state.padding = 0;
+
+    return ngx_http_v2_state_skip(h2c, pos, end);
+}
+
+
+static u_char *
+ngx_http_v2_state_skip(ngx_http_v2_connection_t *h2c, u_char *pos, u_char *end)
+{
+    size_t  size;
+
+    size = end - pos;
+
+    if (size < h2c->state.length) {
+        ngx_log_debug2(NGX_LOG_DEBUG_HTTP, h2c->connection->log, 0,
+                       "http2 frame skip %uz of %uz", size, h2c->state.length);
+
+        h2c->state.length -= size;
+        return ngx_http_v2_state_save(h2c, end, end, ngx_http_v2_state_skip);
+    }
+
+    ngx_log_debug1(NGX_LOG_DEBUG_HTTP, h2c->connection->log, 0,
+                   "http2 frame skip %uz", h2c->state.length);
+
+    return ngx_http_v2_state_complete(h2c, pos + h2c->state.length, end);
+}
+
+
+static u_char *
+ngx_http_v2_state_skip_headers(ngx_http_v2_connection_t *h2c, u_char *pos,
+    u_char *end)
+{
+    h2c->state.pool = ngx_create_pool(1024, h2c->connection->log);
+    if (h2c->state.pool == NULL) {
+        return ngx_http_v2_connection_error(h2c, NGX_HTTP_V2_INTERNAL_ERROR);
+    }
+
+    return ngx_http_v2_state_header_block(h2c, pos, end);
+}
+
+
+static u_char *
+ngx_http_v2_state_save(ngx_http_v2_connection_t *h2c, u_char *pos, u_char *end,
+    ngx_http_v2_handler_pt handler)
+{
+    size_t  size;
+
+    ngx_log_debug3(NGX_LOG_DEBUG_HTTP, h2c->connection->log, 0,
+                   "http2 frame state save pos:%p end:%p handler:%p",
+                   pos, end, handler);
+
+    size = end - pos;
+
+    if (size > NGX_HTTP_V2_STATE_BUFFER_SIZE) {
+        ngx_log_error(NGX_LOG_ALERT, h2c->connection->log, 0,
+                      "state buffer overflow: %uz bytes required", size);
+
+        return ngx_http_v2_connection_error(h2c, NGX_HTTP_V2_INTERNAL_ERROR);
+    }
+
+    ngx_memcpy(h2c->state.buffer, pos, NGX_HTTP_V2_STATE_BUFFER_SIZE);
+
+    h2c->state.buffer_used = size;
+    h2c->state.handler = handler;
+    h2c->state.incomplete = 1;
+
+    return end;
+}
+
+
+static u_char *
+ngx_http_v2_connection_error(ngx_http_v2_connection_t *h2c,
+    ngx_uint_t err)
+{
+    ngx_log_debug0(NGX_LOG_DEBUG_HTTP, h2c->connection->log, 0,
+                   "http2 state connection error");
+
+    if (err == NGX_HTTP_V2_INTERNAL_ERROR) {
+        ngx_debug_point();
+    }
+
+    if (h2c->state.stream) {
+        h2c->state.stream->out_closed = 1;
+        h2c->state.pool = NULL;
+        ngx_http_v2_close_stream(h2c->state.stream, NGX_HTTP_BAD_REQUEST);
+    }
+
+    ngx_http_v2_finalize_connection(h2c, err);
+
+    return NULL;
+}
+
+
+static ngx_int_t
+ngx_http_v2_parse_int(ngx_http_v2_connection_t *h2c, u_char **pos, u_char *end,
+    ngx_uint_t prefix)
+{
+    u_char      *start, *p;
+    ngx_uint_t   value, octet, shift;
+
+    start = *pos;
+    p = start;
+
+    value = *p++ & prefix;
+
+    if (value != prefix) {
+        if (h2c->state.length == 0) {
+            return NGX_ERROR;
+        }
+
+        h2c->state.length--;
+
+        *pos = p;
+        return value;
+    }
+
+    if (end - p > NGX_HTTP_V2_INT_OCTETS - 1) {
+        end = p + NGX_HTTP_V2_INT_OCTETS - 1;
+    }
+
+    for (shift = 0; p != end; shift += 7) {
+        octet = *p++;
+
+        value += (octet & 0x7f) << shift;
+
+        if (octet < 128) {
+            if ((size_t) (p - start) > h2c->state.length) {
+                return NGX_ERROR;
+            }
+
+            h2c->state.length -= p - start;
+
+            *pos = p;
+            return value;
+        }
+    }
+
+    if ((size_t) (end - start) >= NGX_HTTP_V2_INT_OCTETS) {
+        return NGX_DECLINED;
+    }
+
+    if ((size_t) (end - start) >= h2c->state.length) {
+        return NGX_ERROR;
+    }
+
+    return NGX_AGAIN;
+}
+
+
+static ngx_int_t
+ngx_http_v2_send_settings(ngx_http_v2_connection_t *h2c, ngx_uint_t ack)
+{
+    size_t                    len;
+    ngx_buf_t                *buf;
+    ngx_chain_t              *cl;
+    ngx_http_v2_srv_conf_t   *h2scf;
+    ngx_http_v2_out_frame_t  *frame;
+
+    ngx_log_debug0(NGX_LOG_DEBUG_HTTP, h2c->connection->log, 0,
+                   "http2 send SETTINGS frame");
+
+    frame = ngx_palloc(h2c->pool, sizeof(ngx_http_v2_out_frame_t));
+    if (frame == NULL) {
+        return NGX_ERROR;
+    }
+
+    cl = ngx_alloc_chain_link(h2c->pool);
+    if (cl == NULL) {
+        return NGX_ERROR;
+    }
+
+    len = ack ? 0 : (sizeof(uint16_t) + sizeof(uint32_t)) * 3;
+
+    buf = ngx_create_temp_buf(h2c->pool, NGX_HTTP_V2_FRAME_HEADER_SIZE + len);
+    if (buf == NULL) {
+        return NGX_ERROR;
+    }
+
+    buf->last_buf = 1;
+
+    cl->buf = buf;
+    cl->next = NULL;
+
+    frame->first = cl;
+    frame->last = cl;
+    frame->handler = ngx_http_v2_settings_frame_handler;
+    frame->stream = NULL;
+#if (NGX_DEBUG)
+    frame->length = len;
+#endif
+    frame->blocked = 0;
+
+    buf->last = ngx_http_v2_write_len_and_type(buf->last, len,
+                                               NGX_HTTP_V2_SETTINGS_FRAME);
+
+    *buf->last++ = ack ? NGX_HTTP_V2_ACK_FLAG : NGX_HTTP_V2_NO_FLAG;
+
+    buf->last = ngx_http_v2_write_sid(buf->last, 0);
+
+    if (!ack) {
+        h2scf = ngx_http_get_module_srv_conf(h2c->http_connection->conf_ctx,
+                                             ngx_http_v2_module);
+
+        buf->last = ngx_http_v2_write_uint16(buf->last,
+                                             NGX_HTTP_V2_MAX_STREAMS_SETTING);
+        buf->last = ngx_http_v2_write_uint32(buf->last,
+                                             h2scf->concurrent_streams);
+
+        buf->last = ngx_http_v2_write_uint16(buf->last,
+                                         NGX_HTTP_V2_INIT_WINDOW_SIZE_SETTING);
+        buf->last = ngx_http_v2_write_uint32(buf->last,
+                                             NGX_HTTP_V2_MAX_WINDOW);
+
+        buf->last = ngx_http_v2_write_uint16(buf->last,
+                                           NGX_HTTP_V2_MAX_FRAME_SIZE_SETTING);
+        buf->last = ngx_http_v2_write_uint32(buf->last,
+                                             NGX_HTTP_V2_MAX_FRAME_SIZE);
+    }
+
+    ngx_http_v2_queue_blocked_frame(h2c, frame);
+
+    return NGX_OK;
+}
+
+
+static ngx_int_t
+ngx_http_v2_settings_frame_handler(ngx_http_v2_connection_t *h2c,
+    ngx_http_v2_out_frame_t *frame)
+{
+    ngx_buf_t  *buf;
+
+    buf = frame->first->buf;
+
+    if (buf->pos != buf->last) {
+        return NGX_AGAIN;
+    }
+
+    ngx_free_chain(h2c->pool, frame->first);
+
+    return NGX_OK;
+}
+
+
+static ngx_int_t
+ngx_http_v2_send_window_update(ngx_http_v2_connection_t *h2c, ngx_uint_t sid,
+    size_t window)
+{
+    ngx_buf_t                *buf;
+    ngx_http_v2_out_frame_t  *frame;
+
+    frame = ngx_http_v2_get_frame(h2c, NGX_HTTP_V2_WINDOW_UPDATE_SIZE,
+                                  NGX_HTTP_V2_WINDOW_UPDATE_FRAME,
+                                  NGX_HTTP_V2_NO_FLAG, sid);
+    if (frame == NULL) {
+        return NGX_ERROR;
+    }
+
+    buf = frame->first->buf;
+
+    buf->last = ngx_http_v2_write_uint32(buf->last, window);
+
+    ngx_http_v2_queue_blocked_frame(h2c, frame);
+
+    return NGX_OK;
+}
+
+
+static ngx_int_t
+ngx_http_v2_send_rst_stream(ngx_http_v2_connection_t *h2c, ngx_uint_t sid,
+    ngx_uint_t status)
+{
+    ngx_buf_t                *buf;
+    ngx_http_v2_out_frame_t  *frame;
+
+    frame = ngx_http_v2_get_frame(h2c, NGX_HTTP_V2_RST_STREAM_SIZE,
+                                  NGX_HTTP_V2_RST_STREAM_FRAME,
+                                  NGX_HTTP_V2_NO_FLAG, sid);
+    if (frame == NULL) {
+        return NGX_ERROR;
+    }
+
+    buf = frame->first->buf;
+
+    buf->last = ngx_http_v2_write_uint32(buf->last, status);
+
+    ngx_http_v2_queue_blocked_frame(h2c, frame);
+
+    return NGX_OK;
+}
+
+
+static ngx_int_t
+ngx_http_v2_send_goaway(ngx_http_v2_connection_t *h2c, ngx_uint_t status)
+{
+    ngx_buf_t                *buf;
+    ngx_http_v2_out_frame_t  *frame;
+
+    frame = ngx_http_v2_get_frame(h2c, NGX_HTTP_V2_GOAWAY_SIZE,
+                                  NGX_HTTP_V2_GOAWAY_FRAME,
+                                  NGX_HTTP_V2_NO_FLAG, 0);
+    if (frame == NULL) {
+        return NGX_ERROR;
+    }
+
+    buf = frame->first->buf;
+
+    buf->last = ngx_http_v2_write_sid(buf->last, h2c->last_sid);
+    buf->last = ngx_http_v2_write_uint32(buf->last, status);
+
+    ngx_http_v2_queue_blocked_frame(h2c, frame);
+
+    return NGX_OK;
+}
+
+
+static ngx_http_v2_out_frame_t *
+ngx_http_v2_get_frame(ngx_http_v2_connection_t *h2c, size_t length,
+    ngx_uint_t type, u_char flags, ngx_uint_t sid)
+{
+    ngx_buf_t                *buf;
+    ngx_pool_t               *pool;
+    ngx_http_v2_out_frame_t  *frame;
+
+    frame = h2c->free_frames;
+
+    if (frame) {
+        h2c->free_frames = frame->next;
+
+        buf = frame->first->buf;
+        buf->pos = buf->start;
+
+        frame->blocked = 0;
+
+    } else {
+        pool = h2c->pool ? h2c->pool : h2c->connection->pool;
+
+        frame = ngx_pcalloc(pool, sizeof(ngx_http_v2_out_frame_t));
+        if (frame == NULL) {
+            return NULL;
+        }
+
+        frame->first = ngx_alloc_chain_link(pool);
+        if (frame->first == NULL) {
+            return NULL;
+        }
+
+        buf = ngx_create_temp_buf(pool, NGX_HTTP_V2_FRAME_BUFFER_SIZE);
+        if (buf == NULL) {
+            return NULL;
+        }
+
+        buf->last_buf = 1;
+
+        frame->first->buf = buf;
+        frame->last = frame->first;
+
+        frame->handler = ngx_http_v2_frame_handler;
+    }
+
+#if (NGX_DEBUG)
+    if (length > NGX_HTTP_V2_FRAME_BUFFER_SIZE - NGX_HTTP_V2_FRAME_HEADER_SIZE)
+    {
+        ngx_log_error(NGX_LOG_ALERT, h2c->connection->log, 0,
+                      "requested control frame is too large: %uz", length);
+        return NULL;
+    }
+
+    frame->length = length;
+#endif
+
+    buf->last = ngx_http_v2_write_len_and_type(buf->pos, length, type);
+
+    *buf->last++ = flags;
+
+    buf->last = ngx_http_v2_write_sid(buf->last, sid);
+
+    return frame;
+}
+
+
+static ngx_int_t
+ngx_http_v2_frame_handler(ngx_http_v2_connection_t *h2c,
+    ngx_http_v2_out_frame_t *frame)
+{
+    ngx_buf_t  *buf;
+
+    buf = frame->first->buf;
+
+    if (buf->pos != buf->last) {
+        return NGX_AGAIN;
+    }
+
+    frame->next = h2c->free_frames;
+    h2c->free_frames = frame;
+
+    return NGX_OK;
+}
+
+
+static ngx_http_v2_stream_t *
+ngx_http_v2_create_stream(ngx_http_v2_connection_t *h2c)
+{
+    ngx_log_t                 *log;
+    ngx_event_t               *rev, *wev;
+    ngx_connection_t          *fc;
+    ngx_http_log_ctx_t        *ctx;
+    ngx_http_request_t        *r;
+    ngx_http_v2_stream_t      *stream;
+    ngx_http_core_srv_conf_t  *cscf;
+
+    fc = h2c->free_fake_connections;
+
+    if (fc) {
+        h2c->free_fake_connections = fc->data;
+
+        rev = fc->read;
+        wev = fc->write;
+        log = fc->log;
+        ctx = log->data;
+
+    } else {
+        fc = ngx_palloc(h2c->pool, sizeof(ngx_connection_t));
+        if (fc == NULL) {
+            return NULL;
+        }
+
+        rev = ngx_palloc(h2c->pool, sizeof(ngx_event_t));
+        if (rev == NULL) {
+            return NULL;
+        }
+
+        wev = ngx_palloc(h2c->pool, sizeof(ngx_event_t));
+        if (wev == NULL) {
+            return NULL;
+        }
+
+        log = ngx_palloc(h2c->pool, sizeof(ngx_log_t));
+        if (log == NULL) {
+            return NULL;
+        }
+
+        ctx = ngx_palloc(h2c->pool, sizeof(ngx_http_log_ctx_t));
+        if (ctx == NULL) {
+            return NULL;
+        }
+
+        ctx->connection = fc;
+        ctx->request = NULL;
+        ctx->current_request = NULL;
+    }
+
+    ngx_memcpy(log, h2c->connection->log, sizeof(ngx_log_t));
+
+    log->data = ctx;
+
+    ngx_memzero(rev, sizeof(ngx_event_t));
+
+    rev->data = fc;
+    rev->ready = 1;
+    rev->handler = ngx_http_v2_close_stream_handler;
+    rev->log = log;
+
+    ngx_memcpy(wev, rev, sizeof(ngx_event_t));
+
+    wev->write = 1;
+
+    ngx_memcpy(fc, h2c->connection, sizeof(ngx_connection_t));
+
+    fc->data = h2c->http_connection;
+    fc->read = rev;
+    fc->write = wev;
+    fc->sent = 0;
+    fc->log = log;
+    fc->buffered = 0;
+    fc->sndlowat = 1;
+    fc->tcp_nodelay = NGX_TCP_NODELAY_DISABLED;
+
+    r = ngx_http_create_request(fc);
+    if (r == NULL) {
+        return NULL;
+    }
+
+    r->http_version = NGX_HTTP_VERSION_20;
+    r->valid_location = 1;
+
+    fc->data = r;
+    h2c->connection->requests++;
+
+    cscf = ngx_http_get_module_srv_conf(r, ngx_http_core_module);
+
+    r->header_in = ngx_create_temp_buf(r->pool,
+                                       cscf->client_header_buffer_size);
+    if (r->header_in == NULL) {
+        ngx_http_free_request(r, NGX_HTTP_INTERNAL_SERVER_ERROR);
+        return NULL;
+    }
+
+    if (ngx_list_init(&r->headers_in.headers, r->pool, 20,
+                      sizeof(ngx_table_elt_t))
+        != NGX_OK)
+    {
+        ngx_http_free_request(r, NGX_HTTP_INTERNAL_SERVER_ERROR);
+        return NULL;
+    }
+
+    r->headers_in.connection_type = NGX_HTTP_CONNECTION_CLOSE;
+
+    stream = ngx_pcalloc(r->pool, sizeof(ngx_http_v2_stream_t));
+    if (stream == NULL) {
+        ngx_http_free_request(r, NGX_HTTP_INTERNAL_SERVER_ERROR);
+        return NULL;
+    }
+
+    r->stream = stream;
+
+    stream->request = r;
+    stream->connection = h2c;
+
+    stream->send_window = h2c->init_window;
+    stream->recv_window = NGX_HTTP_V2_MAX_WINDOW;
+
+    h2c->processing++;
+
+    return stream;
+}
+
+
+static ngx_http_v2_node_t *
+ngx_http_v2_get_node_by_id(ngx_http_v2_connection_t *h2c, ngx_uint_t sid,
+    ngx_uint_t alloc)
+{
+    ngx_uint_t               index;
+    ngx_http_v2_node_t      *node;
+    ngx_http_v2_srv_conf_t  *h2scf;
+
+    h2scf = ngx_http_get_module_srv_conf(h2c->http_connection->conf_ctx,
+                                         ngx_http_v2_module);
+
+    index = ngx_http_v2_index(h2scf, sid);
+
+    for (node = h2c->streams_index[index]; node; node = node->index) {
+
+        if (node->id == sid) {
+            return node;
+        }
+    }
+
+    if (!alloc) {
+        return NULL;
+    }
+
+    if (h2c->closed_nodes < 32) {
+        node = ngx_pcalloc(h2c->connection->pool, sizeof(ngx_http_v2_node_t));
+        if (node == NULL) {
+            return NULL;
+        }
+
+    } else {
+        node = ngx_http_v2_get_closed_node(h2c);
+    }
+
+    node->id = sid;
+
+    ngx_queue_init(&node->children);
+
+    node->index = h2c->streams_index[index];
+    h2c->streams_index[index] = node;
+
+    return node;
+}
+
+
+static ngx_http_v2_node_t *
+ngx_http_v2_get_closed_node(ngx_http_v2_connection_t *h2c)
+{
+    ngx_uint_t               weight;
+    ngx_queue_t             *q, *children;
+    ngx_http_v2_node_t      *node, **next, *n, *parent, *child;
+    ngx_http_v2_srv_conf_t  *h2scf;
+
+    h2scf = ngx_http_get_module_srv_conf(h2c->http_connection->conf_ctx,
+                                         ngx_http_v2_module);
+
+    h2c->closed_nodes--;
+
+    q = ngx_queue_head(&h2c->closed);
+
+    ngx_queue_remove(q);
+
+    node = ngx_queue_data(q, ngx_http_v2_node_t, reuse);
+
+    next = &h2c->streams_index[ngx_http_v2_index(h2scf, node->id)];
+
+    for ( ;; ) {
+        n = *next;
+
+        if (n == node) {
+            *next = n->index;
+            break;
+        }
+
+        next = &n->index;
+    }
+
+    ngx_queue_remove(&node->queue);
+
+    weight = 0;
+
+    for (q = ngx_queue_head(&node->children);
+         q != ngx_queue_sentinel(&node->children);
+         q = ngx_queue_next(q))
+    {
+        child = ngx_queue_data(q, ngx_http_v2_node_t, queue);
+        weight += child->weight;
+    }
+
+    for (q = ngx_queue_head(&node->children);
+         q != ngx_queue_sentinel(&node->children);
+         q = ngx_queue_next(q))
+    {
+        child = ngx_queue_data(q, ngx_http_v2_node_t, queue);
+        child->weight = node->weight * child->weight / weight;
+
+        if (child->weight == 0) {
+            child->weight = 1;
+        }
+    }
+
+    parent = node->parent;
+
+    if (parent == NGX_HTTP_V2_ROOT) {
+        node->rank = 0;
+        node->rel_weight = 1.0;
+
+        children = &h2c->dependencies;
+
+    } else {
+        node->rank = parent->rank;
+        node->rel_weight = parent->rel_weight;
+
+        children = &parent->children;
+    }
+
+    ngx_http_v2_node_children_update(node);
+    ngx_queue_add(children, &node->children);
+
+    ngx_memzero(node, sizeof(ngx_http_v2_node_t));
+
+    return node;
+}
+
+
+static ngx_int_t
+ngx_http_v2_validate_header(ngx_http_request_t *r, ngx_http_v2_header_t *header)
+{
+    u_char                     ch;
+    ngx_uint_t                 i;
+    ngx_http_core_srv_conf_t  *cscf;
+
+    if (header->name.len == 0) {
+        return NGX_ERROR;
+    }
+
+    cscf = ngx_http_get_module_srv_conf(r, ngx_http_core_module);
+
+    for (i = (header->name.data[0] == ':'); i != header->name.len; i++) {
+        ch = header->name.data[i];
+
+        if ((ch >= 'a' && ch <= 'z')
+            || (ch == '-')
+            || (ch >= '0' && ch <= '9')
+            || (ch == '_' && cscf->underscores_in_headers))
+        {
+            continue;
+        }
+
+        switch (ch) {
+        case '\0':
+        case LF:
+        case CR:
+        case ':':
+            ngx_log_error(NGX_LOG_INFO, r->connection->log, 0,
+                          "client sent invalid header name: \"%V\"",
+                          &header->name);
+
+            return NGX_ERROR;
+        }
+
+        if (ch >= 'A' && ch <= 'Z') {
+            ngx_log_error(NGX_LOG_INFO, r->connection->log, 0,
+                          "client sent invalid header name: \"%V\"",
+                          &header->name);
+
+            return NGX_ERROR;
+        }
+
+        r->invalid_header = 1;
+    }
+
+    for (i = 0; i != header->value.len; i++) {
+        ch = header->value.data[i];
+
+        switch (ch) {
+        case '\0':
+        case LF:
+        case CR:
+            ngx_log_error(NGX_LOG_INFO, r->connection->log, 0,
+                          "client sent header \"%V\" with "
+                          "invalid value: \"%V\"",
+                          &header->name, &header->value);
+
+            return NGX_ERROR;
+        }
+    }
+
+    return NGX_OK;
+}
+
+
+static ngx_int_t
+ngx_http_v2_pseudo_header(ngx_http_request_t *r, ngx_http_v2_header_t *header)
+{
+    header->name.len--;
+    header->name.data++;
+
+    switch (header->name.len) {
+    case 4:
+        if (ngx_memcmp(header->name.data, "path", sizeof("path") - 1)
+            == 0)
+        {
+            return ngx_http_v2_parse_path(r, header);
+        }
+
+        break;
+
+    case 6:
+        if (ngx_memcmp(header->name.data, "method", sizeof("method") - 1)
+            == 0)
+        {
+            return ngx_http_v2_parse_method(r, header);
+        }
+
+        if (ngx_memcmp(header->name.data, "scheme", sizeof("scheme") - 1)
+            == 0)
+        {
+            return ngx_http_v2_parse_scheme(r, header);
+        }
+
+        break;
+
+    case 9:
+        if (ngx_memcmp(header->name.data, "authority", sizeof("authority") - 1)
+            == 0)
+        {
+            return ngx_http_v2_parse_authority(r, header);
+        }
+
+        break;
+    }
+
+    ngx_log_error(NGX_LOG_INFO, r->connection->log, 0,
+                  "client sent unknown pseudo header \"%V\"",
+                  &header->name);
+
+    return NGX_DECLINED;
+}
+
+
+static ngx_int_t
+ngx_http_v2_parse_path(ngx_http_request_t *r, ngx_http_v2_header_t *header)
+{
+    if (r->unparsed_uri.len) {
+        ngx_log_error(NGX_LOG_INFO, r->connection->log, 0,
+                      "client sent duplicate :path header");
+
+        return NGX_DECLINED;
+    }
+
+    if (header->value.len == 0) {
+        ngx_log_error(NGX_LOG_INFO, r->connection->log, 0,
+                      "client sent empty :path header");
+
+        return NGX_DECLINED;
+    }
+
+    r->uri_start = header->value.data;
+    r->uri_end = header->value.data + header->value.len;
+
+    if (ngx_http_parse_uri(r) != NGX_OK) {
+        ngx_log_error(NGX_LOG_INFO, r->connection->log, 0,
+                      "client sent invalid :path header: \"%V\"",
+                      &header->value);
+
+        return NGX_DECLINED;
+    }
+
+    if (ngx_http_process_request_uri(r) != NGX_OK) {
+        /*
+         * request has been finalized already
+         * in ngx_http_process_request_uri()
+         */
+        return NGX_ABORT;
+    }
+
+    return NGX_OK;
+}
+
+
+static ngx_int_t
+ngx_http_v2_parse_method(ngx_http_request_t *r, ngx_http_v2_header_t *header)
+{
+    size_t         k, len;
+    ngx_uint_t     n;
+    const u_char  *p, *m;
+
+    /*
+     * This array takes less than 256 sequential bytes,
+     * and if typical CPU cache line size is 64 bytes,
+     * it is prefetched for 4 load operations.
+     */
+    static const struct {
+        u_char            len;
+        const u_char      method[11];
+        uint32_t          value;
+    } tests[] = {
+        { 3, "GET",       NGX_HTTP_GET },
+        { 4, "POST",      NGX_HTTP_POST },
+        { 4, "HEAD",      NGX_HTTP_HEAD },
+        { 7, "OPTIONS",   NGX_HTTP_OPTIONS },
+        { 8, "PROPFIND",  NGX_HTTP_PROPFIND },
+        { 3, "PUT",       NGX_HTTP_PUT },
+        { 5, "MKCOL",     NGX_HTTP_MKCOL },
+        { 6, "DELETE",    NGX_HTTP_DELETE },
+        { 4, "COPY",      NGX_HTTP_COPY },
+        { 4, "MOVE",      NGX_HTTP_MOVE },
+        { 9, "PROPPATCH", NGX_HTTP_PROPPATCH },
+        { 4, "LOCK",      NGX_HTTP_LOCK },
+        { 6, "UNLOCK",    NGX_HTTP_UNLOCK },
+        { 5, "PATCH",     NGX_HTTP_PATCH },
+        { 5, "TRACE",     NGX_HTTP_TRACE }
+    }, *test;
+
+    if (r->method_name.len) {
+        ngx_log_error(NGX_LOG_INFO, r->connection->log, 0,
+                      "client sent duplicate :method header");
+
+        return NGX_DECLINED;
+    }
+
+    if (header->value.len == 0) {
+        ngx_log_error(NGX_LOG_INFO, r->connection->log, 0,
+                      "client sent empty :method header");
+
+        return NGX_DECLINED;
+    }
+
+    r->method_name.len = header->value.len;
+    r->method_name.data = header->value.data;
+
+    len = r->method_name.len;
+    n = sizeof(tests) / sizeof(tests[0]);
+    test = tests;
+
+    do {
+        if (len == test->len) {
+            p = r->method_name.data;
+            m = test->method;
+            k = len;
+
+            do {
+                if (*p++ != *m++) {
+                    goto next;
+                }
+            } while (--k);
+
+            r->method = test->value;
+            return NGX_OK;
+        }
+
+    next:
+        test++;
+
+    } while (--n);
+
+    p = r->method_name.data;
+
+    do {
+        if ((*p < 'A' || *p > 'Z') && *p != '_') {
+            ngx_log_error(NGX_LOG_INFO, r->connection->log, 0,
+                          "client sent invalid method: \"%V\"",
+                          &r->method_name);
+
+            return NGX_DECLINED;
+        }
+
+        p++;
+
+    } while (--len);
+
+    return NGX_OK;
+}
+
+
+static ngx_int_t
+ngx_http_v2_parse_scheme(ngx_http_request_t *r, ngx_http_v2_header_t *header)
+{
+    if (r->schema_start) {
+        ngx_log_error(NGX_LOG_INFO, r->connection->log, 0,
+                      "client sent duplicate :schema header");
+
+        return NGX_DECLINED;
+    }
+
+    if (header->value.len == 0) {
+        ngx_log_error(NGX_LOG_INFO, r->connection->log, 0,
+                      "client sent empty :schema header");
+
+        return NGX_DECLINED;
+    }
+
+    r->schema_start = header->value.data;
+    r->schema_end = header->value.data + header->value.len;
+
+    return NGX_OK;
+}
+
+
+static ngx_int_t
+ngx_http_v2_parse_authority(ngx_http_request_t *r, ngx_http_v2_header_t *header)
+{
+    ngx_table_elt_t            *h;
+    ngx_http_header_t          *hh;
+    ngx_http_core_main_conf_t  *cmcf;
+
+    static ngx_str_t host = ngx_string("host");
+
+    h = ngx_list_push(&r->headers_in.headers);
+    if (h == NULL) {
+        return NGX_ERROR;
+    }
+
+    h->hash = ngx_hash_key(host.data, host.len);
+
+    h->key.len = host.len;
+    h->key.data = host.data;
+
+    h->value.len = header->value.len;
+    h->value.data = header->value.data;
+
+    h->lowcase_key = host.data;
+
+    cmcf = ngx_http_get_module_main_conf(r, ngx_http_core_module);
+
+    hh = ngx_hash_find(&cmcf->headers_in_hash, h->hash,
+                       h->lowcase_key, h->key.len);
+
+    if (hh == NULL) {
+        return NGX_ERROR;
+    }
+
+    if (hh->handler(r, h, hh->offset) != NGX_OK) {
+        /*
+         * request has been finalized already
+         * in ngx_http_process_host()
+         */
+        return NGX_ABORT;
+    }
+
+    return NGX_OK;
+}
+
+
+static ngx_int_t
+ngx_http_v2_construct_request_line(ngx_http_request_t *r)
+{
+    u_char  *p;
+
+    static const u_char ending[] = " HTTP/2.0";
+
+    if (r->method_name.len == 0
+        || r->unparsed_uri.len == 0)
+    {
+        ngx_http_finalize_request(r, NGX_HTTP_BAD_REQUEST);
+        return NGX_ERROR;
+    }
+
+    r->request_line.len = r->method_name.len + 1
+                          + r->unparsed_uri.len
+                          + sizeof(ending) - 1;
+
+    p = ngx_pnalloc(r->pool, r->request_line.len + 1);
+    if (p == NULL) {
+        ngx_http_v2_close_stream(r->stream, NGX_HTTP_INTERNAL_SERVER_ERROR);
+        return NGX_ERROR;
+    }
+
+    r->request_line.data = p;
+
+    p = ngx_cpymem(p, r->method_name.data, r->method_name.len);
+
+    *p++ = ' ';
+
+    p = ngx_cpymem(p, r->unparsed_uri.data, r->unparsed_uri.len);
+
+    ngx_memcpy(p, ending, sizeof(ending));
+
+    /* some modules expect the space character after method name */
+    r->method_name.data = r->request_line.data;
+
+    ngx_log_debug1(NGX_LOG_DEBUG_HTTP, r->connection->log, 0,
+                   "http2 http request line: \"%V\"", &r->request_line);
+
+    return NGX_OK;
+}
+
+
+static ngx_int_t
+ngx_http_v2_cookie(ngx_http_request_t *r, ngx_http_v2_header_t *header)
+{
+    ngx_str_t    *val;
+    ngx_array_t  *cookies;
+
+    cookies = r->stream->cookies;
+
+    if (cookies == NULL) {
+        cookies = ngx_array_create(r->pool, 2, sizeof(ngx_str_t));
+        if (cookies == NULL) {
+            return NGX_ERROR;
+        }
+
+        r->stream->cookies = cookies;
+    }
+
+    val = ngx_array_push(cookies);
+    if (val == NULL) {
+        return NGX_ERROR;
+    }
+
+    val->len = header->value.len;
+    val->data = header->value.data;
+
+    return NGX_OK;
+}
+
+
+static ngx_int_t
+ngx_http_v2_construct_cookie_header(ngx_http_request_t *r)
+{
+    u_char                     *buf, *p, *end;
+    size_t                      len;
+    ngx_str_t                  *vals;
+    ngx_uint_t                  i;
+    ngx_array_t                *cookies;
+    ngx_table_elt_t            *h;
+    ngx_http_header_t          *hh;
+    ngx_http_core_main_conf_t  *cmcf;
+
+    static ngx_str_t cookie = ngx_string("cookie");
+
+    cookies = r->stream->cookies;
+
+    if (cookies == NULL) {
+        return NGX_OK;
+    }
+
+    vals = cookies->elts;
+
+    i = 0;
+    len = 0;
+
+    do {
+        len += vals[i].len + 2;
+    } while (++i != cookies->nelts);
+
+    len -= 2;
+
+    buf = ngx_pnalloc(r->pool, len + 1);
+    if (buf == NULL) {
+        ngx_http_v2_close_stream(r->stream, NGX_HTTP_INTERNAL_SERVER_ERROR);
+        return NGX_ERROR;
+    }
+
+    p = buf;
+    end = buf + len;
+
+    for (i = 0; /* void */ ; i++) {
+
+        p = ngx_cpymem(p, vals[i].data, vals[i].len);
+
+        if (p == end) {
+            *p = '\0';
+            break;
+        }
+
+        *p++ = ';'; *p++ = ' ';
+    }
+
+    h = ngx_list_push(&r->headers_in.headers);
+    if (h == NULL) {
+        ngx_http_v2_close_stream(r->stream, NGX_HTTP_INTERNAL_SERVER_ERROR);
+        return NGX_ERROR;
+    }
+
+    h->hash = ngx_hash_key(cookie.data, cookie.len);
+
+    h->key.len = cookie.len;
+    h->key.data = cookie.data;
+
+    h->value.len = len;
+    h->value.data = buf;
+
+    h->lowcase_key = cookie.data;
+
+    cmcf = ngx_http_get_module_main_conf(r, ngx_http_core_module);
+
+    hh = ngx_hash_find(&cmcf->headers_in_hash, h->hash,
+                       h->lowcase_key, h->key.len);
+
+    if (hh == NULL) {
+        ngx_http_v2_close_stream(r->stream, NGX_HTTP_INTERNAL_SERVER_ERROR);
+        return NGX_ERROR;
+    }
+
+    if (hh->handler(r, h, hh->offset) != NGX_OK) {
+        /*
+         * request has been finalized already
+         * in ngx_http_process_multi_header_lines()
+         */
+        return NGX_ERROR;
+    }
+
+    return NGX_OK;
+}
+
+
+static void
+ngx_http_v2_run_request(ngx_http_request_t *r)
+{
+    if (ngx_http_v2_construct_request_line(r) != NGX_OK) {
+        return;
+    }
+
+    if (ngx_http_v2_construct_cookie_header(r) != NGX_OK) {
+        return;
+    }
+
+    r->http_state = NGX_HTTP_PROCESS_REQUEST_STATE;
+
+    if (ngx_http_process_request_header(r) != NGX_OK) {
+        return;
+    }
+
+    if (r->headers_in.content_length_n > 0 && r->stream->in_closed) {
+        ngx_log_error(NGX_LOG_INFO, r->connection->log, 0,
+                      "client prematurely closed stream");
+
+        r->stream->skip_data = NGX_HTTP_V2_DATA_ERROR;
+
+        ngx_http_finalize_request(r, NGX_HTTP_BAD_REQUEST);
+        return;
+    }
+
+    ngx_http_process_request(r);
+}
+
+
+static ngx_int_t
+ngx_http_v2_init_request_body(ngx_http_request_t *r)
+{
+    ngx_buf_t                 *buf;
+    ngx_temp_file_t           *tf;
+    ngx_http_request_body_t   *rb;
+    ngx_http_core_loc_conf_t  *clcf;
+
+    rb = ngx_pcalloc(r->pool, sizeof(ngx_http_request_body_t));
+    if (rb == NULL) {
+        return NGX_ERROR;
+    }
+
+    r->request_body = rb;
+
+    if (r->stream->in_closed) {
+        return NGX_OK;
+    }
+
+    rb->rest = r->headers_in.content_length_n;
+
+    clcf = ngx_http_get_module_loc_conf(r, ngx_http_core_module);
+
+    if (r->request_body_in_file_only
+        || rb->rest > (off_t) clcf->client_body_buffer_size
+        || rb->rest < 0)
+    {
+        tf = ngx_pcalloc(r->pool, sizeof(ngx_temp_file_t));
+        if (tf == NULL) {
+            return NGX_ERROR;
+        }
+
+        tf->file.fd = NGX_INVALID_FILE;
+        tf->file.log = r->connection->log;
+        tf->path = clcf->client_body_temp_path;
+        tf->pool = r->pool;
+        tf->warn = "a client request body is buffered to a temporary file";
+        tf->log_level = r->request_body_file_log_level;
+        tf->persistent = r->request_body_in_persistent_file;
+        tf->clean = r->request_body_in_clean_file;
+
+        if (r->request_body_file_group_access) {
+            tf->access = 0660;
+        }
+
+        rb->temp_file = tf;
+
+        if (r->stream->in_closed
+            && ngx_create_temp_file(&tf->file, tf->path, tf->pool,
+                                    tf->persistent, tf->clean, tf->access)
+               != NGX_OK)
+        {
+            return NGX_ERROR;
+        }
+
+        buf = ngx_calloc_buf(r->pool);
+        if (buf == NULL) {
+            return NGX_ERROR;
+        }
+
+    } else {
+
+        if (rb->rest == 0) {
+            return NGX_OK;
+        }
+
+        buf = ngx_create_temp_buf(r->pool, (size_t) rb->rest);
+        if (buf == NULL) {
+            return NGX_ERROR;
+        }
+    }
+
+    rb->buf = buf;
+
+    rb->bufs = ngx_alloc_chain_link(r->pool);
+    if (rb->bufs == NULL) {
+        return NGX_ERROR;
+    }
+
+    rb->bufs->buf = buf;
+    rb->bufs->next = NULL;
+
+    rb->rest = 0;
+
+    return NGX_OK;
+}
+
+
+ngx_int_t
+ngx_http_v2_read_request_body(ngx_http_request_t *r,
+    ngx_http_client_body_handler_pt post_handler)
+{
+    ngx_http_v2_stream_t  *stream;
+
+    ngx_log_debug0(NGX_LOG_DEBUG_HTTP, r->connection->log, 0,
+                   "http2 read request body");
+
+    stream = r->stream;
+
+    switch (stream->skip_data) {
+
+    case NGX_HTTP_V2_DATA_DISCARD:
+        post_handler(r);
+        return NGX_OK;
+
+    case NGX_HTTP_V2_DATA_ERROR:
+        if (r->headers_in.content_length_n == -1) {
+            return NGX_HTTP_REQUEST_ENTITY_TOO_LARGE;
+        } else {
+            return NGX_HTTP_BAD_REQUEST;
+        }
+
+    case NGX_HTTP_V2_DATA_INTERNAL_ERROR:
+        return NGX_HTTP_INTERNAL_SERVER_ERROR;
+    }
+
+    if (!r->request_body && ngx_http_v2_init_request_body(r) != NGX_OK) {
+        stream->skip_data = NGX_HTTP_V2_DATA_INTERNAL_ERROR;
+        return NGX_HTTP_INTERNAL_SERVER_ERROR;
+    }
+
+    if (stream->in_closed) {
+        post_handler(r);
+        return NGX_OK;
+    }
+
+    r->request_body->post_handler = post_handler;
+
+    r->read_event_handler = ngx_http_test_reading;
+    r->write_event_handler = ngx_http_request_empty_handler;
+
+    return NGX_AGAIN;
+}
+
+
+static ngx_int_t
+ngx_http_v2_terminate_stream(ngx_http_v2_connection_t *h2c,
+    ngx_http_v2_stream_t *stream, ngx_uint_t status)
+{
+    ngx_event_t       *rev;
+    ngx_connection_t  *fc;
+
+    if (ngx_http_v2_send_rst_stream(h2c, stream->node->id, status)
+        == NGX_ERROR)
+    {
+        return NGX_ERROR;
+    }
+
+    stream->out_closed = 1;
+
+    fc = stream->request->connection;
+    fc->error = 1;
+
+    rev = fc->read;
+    rev->handler(rev);
+
+    return NGX_OK;
+}
+
+
+void
+ngx_http_v2_close_stream(ngx_http_v2_stream_t *stream, ngx_int_t rc)
+{
+    ngx_event_t               *ev;
+    ngx_connection_t          *fc;
+    ngx_http_v2_node_t        *node;
+    ngx_http_v2_connection_t  *h2c;
+
+    h2c = stream->connection;
+    node = stream->node;
+
+    ngx_log_debug3(NGX_LOG_DEBUG_HTTP, h2c->connection->log, 0,
+                   "http2 close stream %ui, queued %ui, processing %ui",
+                   node->id, stream->queued, h2c->processing);
+
+    fc = stream->request->connection;
+
+    if (stream->queued) {
+        fc->write->handler = ngx_http_v2_close_stream_handler;
+        return;
+    }
+
+    if (!stream->out_closed) {
+        if (ngx_http_v2_send_rst_stream(h2c, node->id,
+                                        NGX_HTTP_V2_INTERNAL_ERROR)
+            != NGX_OK)
+        {
+            h2c->connection->error = 1;
+        }
+    }
+
+    node->stream = NULL;
+
+    ngx_queue_insert_tail(&h2c->closed, &node->reuse);
+    h2c->closed_nodes++;
+
+    ngx_http_free_request(stream->request, rc);
+
+    ev = fc->read;
+
+    if (ev->active || ev->disabled) {
+        ngx_log_error(NGX_LOG_ALERT, h2c->connection->log, 0,
+                      "fake read event was activated");
+    }
+
+    if (ev->timer_set) {
+        ngx_del_timer(ev);
+    }
+
+    if (ev->posted) {
+        ngx_delete_posted_event(ev);
+    }
+
+    ev = fc->write;
+
+    if (ev->active || ev->disabled) {
+        ngx_log_error(NGX_LOG_ALERT, h2c->connection->log, 0,
+                      "fake write event was activated");
+    }
+
+    if (ev->timer_set) {
+        ngx_del_timer(ev);
+    }
+
+    if (ev->posted) {
+        ngx_delete_posted_event(ev);
+    }
+
+    fc->data = h2c->free_fake_connections;
+    h2c->free_fake_connections = fc;
+
+    h2c->processing--;
+
+    if (h2c->processing || h2c->blocked) {
+        return;
+    }
+
+    ev = h2c->connection->read;
+
+    ev->handler = ngx_http_v2_handle_connection_handler;
+    ngx_post_event(ev, &ngx_posted_events);
+}
+
+
+static void
+ngx_http_v2_close_stream_handler(ngx_event_t *ev)
+{
+    ngx_connection_t    *fc;
+    ngx_http_request_t  *r;
+
+    fc = ev->data;
+    r = fc->data;
+
+    ngx_log_debug0(NGX_LOG_DEBUG_HTTP, r->connection->log, 0,
+                   "http2 close stream handler");
+
+    ngx_http_v2_close_stream(r->stream, 0);
+}
+
+
+static void
+ngx_http_v2_handle_connection_handler(ngx_event_t *rev)
+{
+    ngx_connection_t  *c;
+
+    rev->handler = ngx_http_v2_read_handler;
+
+    if (rev->ready) {
+        ngx_http_v2_read_handler(rev);
+        return;
+    }
+
+    c = rev->data;
+
+    ngx_http_v2_handle_connection(c->data);
+}
+
+
+static void
+ngx_http_v2_idle_handler(ngx_event_t *rev)
+{
+    ngx_connection_t          *c;
+    ngx_http_v2_srv_conf_t    *h2scf;
+    ngx_http_v2_connection_t  *h2c;
+
+    c = rev->data;
+    h2c = c->data;
+
+    ngx_log_debug0(NGX_LOG_DEBUG_HTTP, c->log, 0, "http2 idle handler");
+
+    if (rev->timedout || c->close) {
+        ngx_http_v2_finalize_connection(h2c, NGX_HTTP_V2_NO_ERROR);
+        return;
+    }
+
+#if (NGX_HAVE_KQUEUE)
+
+    if (ngx_event_flags & NGX_USE_KQUEUE_EVENT) {
+        if (rev->pending_eof) {
+            c->log->handler = NULL;
+            ngx_log_error(NGX_LOG_INFO, c->log, rev->kq_errno,
+                          "kevent() reported that client %V closed "
+                          "idle connection", &c->addr_text);
+#if (NGX_HTTP_SSL)
+            if (c->ssl) {
+                c->ssl->no_send_shutdown = 1;
+            }
+#endif
+            ngx_http_close_connection(c);
+            return;
+        }
+    }
+
+#endif
+
+    c->destroyed = 0;
+    c->idle = 0;
+    ngx_reusable_connection(c, 0);
+
+    h2scf = ngx_http_get_module_srv_conf(h2c->http_connection->conf_ctx,
+                                         ngx_http_v2_module);
+
+    h2c->pool = ngx_create_pool(h2scf->pool_size, h2c->connection->log);
+    if (h2c->pool == NULL) {
+        ngx_http_v2_finalize_connection(h2c, NGX_HTTP_V2_INTERNAL_ERROR);
+        return;
+    }
+
+    c->write->handler = ngx_http_v2_write_handler;
+
+    rev->handler = ngx_http_v2_read_handler;
+    ngx_http_v2_read_handler(rev);
+}
+
+
+static void
+ngx_http_v2_finalize_connection(ngx_http_v2_connection_t *h2c,
+    ngx_uint_t status)
+{
+    ngx_uint_t               i, size;
+    ngx_event_t             *ev;
+    ngx_connection_t        *c, *fc;
+    ngx_http_request_t      *r;
+    ngx_http_v2_node_t      *node;
+    ngx_http_v2_stream_t    *stream;
+    ngx_http_v2_srv_conf_t  *h2scf;
+
+    c = h2c->connection;
+
+    h2c->blocked = 1;
+
+    if (!c->error && ngx_http_v2_send_goaway(h2c, status) != NGX_ERROR) {
+        (void) ngx_http_v2_send_output_queue(h2c);
+    }
+
+    if (!h2c->processing) {
+        ngx_http_close_connection(c);
+        return;
+    }
+
+    c->error = 1;
+    c->read->handler = ngx_http_empty_handler;
+    c->write->handler = ngx_http_empty_handler;
+
+    h2c->last_out = NULL;
+
+    h2scf = ngx_http_get_module_srv_conf(h2c->http_connection->conf_ctx,
+                                         ngx_http_v2_module);
+
+    size = ngx_http_v2_index_size(h2scf);
+
+    for (i = 0; i < size; i++) {
+
+        for (node = h2c->streams_index[i]; node; node = node->index) {
+            stream = node->stream;
+
+            if (stream == NULL) {
+                continue;
+            }
+
+            stream->handled = 0;
+
+            r = stream->request;
+            fc = r->connection;
+
+            fc->error = 1;
+
+            if (stream->queued) {
+                stream->queued = 0;
+
+                ev = fc->write;
+                ev->delayed = 0;
+
+            } else {
+                ev = fc->read;
+            }
+
+            ev->eof = 1;
+            ev->handler(ev);
+        }
+    }
+
+    h2c->blocked = 0;
+
+    if (h2c->processing) {
+        return;
+    }
+
+    ngx_http_close_connection(c);
+}
+
+
+static ngx_int_t
+ngx_http_v2_adjust_windows(ngx_http_v2_connection_t *h2c, ssize_t delta)
+{
+    ngx_uint_t               i, size;
+    ngx_event_t             *wev;
+    ngx_http_v2_node_t      *node;
+    ngx_http_v2_stream_t    *stream;
+    ngx_http_v2_srv_conf_t  *h2scf;
+
+    h2scf = ngx_http_get_module_srv_conf(h2c->http_connection->conf_ctx,
+                                         ngx_http_v2_module);
+
+    size = ngx_http_v2_index_size(h2scf);
+
+    for (i = 0; i < size; i++) {
+
+        for (node = h2c->streams_index[i]; node; node = node->index) {
+            stream = node->stream;
+
+            if (stream == NULL) {
+                continue;
+            }
+
+            if (delta > 0
+                && stream->send_window
+                      > (ssize_t) (NGX_HTTP_V2_MAX_WINDOW - delta))
+            {
+                if (ngx_http_v2_terminate_stream(h2c, stream,
+                                                 NGX_HTTP_V2_FLOW_CTRL_ERROR)
+                    == NGX_ERROR)
+                {
+                    return NGX_ERROR;
+                }
+
+                continue;
+            }
+
+            stream->send_window += delta;
+
+            ngx_log_debug2(NGX_LOG_DEBUG_HTTP, h2c->connection->log, 0,
+                           "http2:%ui adjusted window: %z",
+                           node->id, stream->send_window);
+
+            if (stream->send_window > 0 && stream->exhausted) {
+                stream->exhausted = 0;
+
+                wev = stream->request->connection->write;
+
+                if (!wev->timer_set) {
+                    wev->delayed = 0;
+                    wev->handler(wev);
+                }
+            }
+        }
+    }
+
+    return NGX_OK;
+}
+
+
+static void
+ngx_http_v2_set_dependency(ngx_http_v2_connection_t *h2c,
+    ngx_http_v2_node_t *node, ngx_uint_t depend, ngx_uint_t exclusive)
+{
+    ngx_queue_t         *children;
+    ngx_http_v2_node_t  *parent, *next;
+
+    parent = depend ? ngx_http_v2_get_node_by_id(h2c, depend, 0) : NULL;
+
+    if (parent == NULL) {
+        parent = NGX_HTTP_V2_ROOT;
+
+        if (depend != 0) {
+            exclusive = 0;
+        }
+
+        node->rank = 1;
+        node->rel_weight = (1.0 / 256) * node->weight;
+
+        children = &h2c->dependencies;
+
+    } else {
+        if (node->parent != NULL) {
+
+            for (next = parent->parent;
+                 next != NGX_HTTP_V2_ROOT && next->rank >= node->rank;
+                 next = next->parent)
+            {
+                if (next != node) {
+                    continue;
+                }
+
+                ngx_queue_remove(&parent->queue);
+                ngx_queue_insert_after(&node->queue, &parent->queue);
+
+                parent->parent = node->parent;
+
+                if (node->parent == NGX_HTTP_V2_ROOT) {
+                    parent->rank = 1;
+                    parent->rel_weight = (1.0 / 256) * parent->weight;
+
+                } else {
+                    parent->rank = node->parent->rank + 1;
+                    parent->rel_weight = (node->parent->rel_weight / 256)
+                                         * parent->weight;
+                }
+
+                if (!exclusive) {
+                    ngx_http_v2_node_children_update(parent);
+                }
+
+                break;
+            }
+        }
+
+        node->rank = parent->rank + 1;
+        node->rel_weight = (parent->rel_weight / 256) * node->weight;
+
+        if (parent->stream == NULL) {
+            ngx_queue_remove(&parent->reuse);
+            ngx_queue_insert_tail(&h2c->closed, &parent->reuse);
+        }
+
+        children = &parent->children;
+    }
+
+    if (exclusive) {
+        ngx_queue_add(&node->children, children);
+        ngx_queue_init(children);
+    }
+
+    if (node->parent != NULL) {
+        ngx_queue_remove(&node->queue);
+    }
+
+    ngx_queue_insert_tail(children, &node->queue);
+
+    node->parent = parent;
+
+    ngx_http_v2_node_children_update(node);
+}
+
+
+static void
+ngx_http_v2_node_children_update(ngx_http_v2_node_t *node)
+{
+    ngx_queue_t         *q;
+    ngx_http_v2_node_t  *child;
+
+    for (q = ngx_queue_head(&node->children);
+         q != ngx_queue_sentinel(&node->children);
+         q = ngx_queue_next(q))
+    {
+        child = ngx_queue_data(q, ngx_http_v2_node_t, queue);
+
+        child->rank = node->rank + 1;
+        child->rel_weight = (node->rel_weight / 256) * child->weight;
+
+        ngx_http_v2_node_children_update(child);
+    }
+}
+
+
+static void
+ngx_http_v2_pool_cleanup(void *data)
+{
+    ngx_http_v2_connection_t  *h2c = data;
+
+    if (h2c->state.pool) {
+        ngx_destroy_pool(h2c->state.pool);
+    }
+
+    if (h2c->pool) {
+        ngx_destroy_pool(h2c->pool);
+    }
+}