changeset 8653:1efee5e4194c quic

HTTP/3: introduced ngx_http_v3_filter. The filter is responsible for creating HTTP/3 response header and body. The change removes differences to the default branch for ngx_http_chunked_filter_module and ngx_http_header_filter_module.
author Roman Arutyunyan <arut@nginx.com>
date Fri, 27 Nov 2020 17:46:21 +0000
parents e9bd4305e68b
children 9ebeed8cd1b8
files auto/modules src/http/modules/ngx_http_chunked_filter_module.c src/http/ngx_http_header_filter_module.c src/http/v3/ngx_http_v3.h src/http/v3/ngx_http_v3_filter_module.c src/http/v3/ngx_http_v3_request.c
diffstat 6 files changed, 1382 insertions(+), 1204 deletions(-) [+]
line wrap: on
line diff
--- a/auto/modules
+++ b/auto/modules
@@ -119,6 +119,7 @@ if [ $HTTP = YES ]; then
     #     ngx_http_header_filter
     #     ngx_http_chunked_filter
     #     ngx_http_v2_filter
+    #     ngx_http_v3_filter
     #     ngx_http_range_header_filter
     #     ngx_http_gzip_filter
     #     ngx_http_postpone_filter
@@ -151,6 +152,7 @@ if [ $HTTP = YES ]; then
                       ngx_http_header_filter_module \
                       ngx_http_chunked_filter_module \
                       ngx_http_v2_filter_module \
+                      ngx_http_v3_filter_module \
                       ngx_http_range_header_filter_module \
                       ngx_http_gzip_filter_module \
                       ngx_http_postpone_filter_module \
@@ -212,6 +214,17 @@ if [ $HTTP = YES ]; then
         . auto/module
     fi
 
+    if [ $HTTP_V3 = YES ]; then
+        ngx_module_name=ngx_http_v3_filter_module
+        ngx_module_incs=
+        ngx_module_deps=
+        ngx_module_srcs=src/http/v3/ngx_http_v3_filter_module.c
+        ngx_module_libs=
+        ngx_module_link=$HTTP_V3
+
+        . auto/module
+    fi
+
     if :; then
         ngx_module_name=ngx_http_range_header_filter_module
         ngx_module_incs=
--- a/src/http/modules/ngx_http_chunked_filter_module.c
+++ b/src/http/modules/ngx_http_chunked_filter_module.c
@@ -106,7 +106,6 @@ ngx_http_chunked_body_filter(ngx_http_re
 {
     u_char                         *chunk;
     off_t                           size;
-    size_t                          n;
     ngx_int_t                       rc;
     ngx_buf_t                      *b;
     ngx_chain_t                    *out, *cl, *tl, **ll;
@@ -162,68 +161,27 @@ ngx_http_chunked_body_filter(ngx_http_re
         chunk = b->start;
 
         if (chunk == NULL) {
-
-#if (NGX_HTTP_V3)
-            if (r->http_version == NGX_HTTP_VERSION_30) {
-                n = NGX_HTTP_V3_VARLEN_INT_LEN * 2;
+            /* the "0000000000000000" is 64-bit hexadecimal string */
 
-            } else
-#endif
-            {
-                /* the "0000000000000000" is 64-bit hexadecimal string */
-                n = sizeof("0000000000000000" CRLF) - 1;
-            }
-
-            chunk = ngx_palloc(r->pool, n);
+            chunk = ngx_palloc(r->pool, sizeof("0000000000000000" CRLF) - 1);
             if (chunk == NULL) {
                 return NGX_ERROR;
             }
 
             b->start = chunk;
-            b->end = chunk + n;
+            b->end = chunk + sizeof("0000000000000000" CRLF) - 1;
         }
 
         b->tag = (ngx_buf_tag_t) &ngx_http_chunked_filter_module;
         b->memory = 0;
         b->temporary = 1;
         b->pos = chunk;
-
-#if (NGX_HTTP_V3)
-        if (r->http_version == NGX_HTTP_VERSION_30) {
-            b->last = (u_char *) ngx_http_v3_encode_varlen_int(chunk,
-                                                       NGX_HTTP_V3_FRAME_DATA);
-            b->last = (u_char *) ngx_http_v3_encode_varlen_int(b->last, size);
-
-        } else
-#endif
-        {
-            b->last = ngx_sprintf(chunk, "%xO" CRLF, size);
-        }
+        b->last = ngx_sprintf(chunk, "%xO" CRLF, size);
 
         tl->next = out;
         out = tl;
     }
 
-#if (NGX_HTTP_V3)
-    if (r->http_version == NGX_HTTP_VERSION_30) {
-
-        if (cl->buf->last_buf) {
-            tl = ngx_http_v3_create_trailers(r);
-            if (tl == NULL) {
-                return NGX_ERROR;
-            }
-
-            cl->buf->last_buf = 0;
-
-            *ll = tl;
-
-        } else {
-            *ll = NULL;
-        }
-
-    } else
-#endif
-
     if (cl->buf->last_buf) {
         tl = ngx_http_chunked_create_trailers(r, ctx);
         if (tl == NULL) {
--- a/src/http/ngx_http_header_filter_module.c
+++ b/src/http/ngx_http_header_filter_module.c
@@ -187,29 +187,6 @@ ngx_http_header_filter(ngx_http_request_
         r->header_only = 1;
     }
 
-    if (r->headers_out.status_line.len == 0) {
-        if (r->headers_out.status == NGX_HTTP_NO_CONTENT
-            || r->headers_out.status == NGX_HTTP_NOT_MODIFIED)
-        {
-            r->header_only = 1;
-        }
-    }
-
-#if (NGX_HTTP_V3)
-
-    if (r->http_version == NGX_HTTP_VERSION_30) {
-        ngx_chain_t  *cl;
-
-        cl = ngx_http_v3_create_header(r);
-        if (cl == NULL) {
-            return NGX_ERROR;
-        }
-
-        return ngx_http_write_filter(r, cl);
-    }
-
-#endif
-
     if (r->headers_out.last_modified_time != -1) {
         if (r->headers_out.status != NGX_HTTP_OK
             && r->headers_out.status != NGX_HTTP_PARTIAL_CONTENT
@@ -243,6 +220,7 @@ ngx_http_header_filter(ngx_http_request_
             /* 2XX */
 
             if (status == NGX_HTTP_NO_CONTENT) {
+                r->header_only = 1;
                 ngx_str_null(&r->headers_out.content_type);
                 r->headers_out.last_modified_time = -1;
                 r->headers_out.last_modified = NULL;
@@ -259,6 +237,10 @@ ngx_http_header_filter(ngx_http_request_
         {
             /* 3XX */
 
+            if (status == NGX_HTTP_NOT_MODIFIED) {
+                r->header_only = 1;
+            }
+
             status = status - NGX_HTTP_MOVED_PERMANENTLY + NGX_HTTP_OFF_3XX;
             status_line = &ngx_http_status_lines[status];
             len += ngx_http_status_lines[status].len;
--- a/src/http/v3/ngx_http_v3.h
+++ b/src/http/v3/ngx_http_v3.h
@@ -140,8 +140,6 @@ ngx_int_t ngx_http_v3_parse_header(ngx_h
     ngx_uint_t allow_underscores);
 ngx_int_t ngx_http_v3_parse_request_body(ngx_http_request_t *r, ngx_buf_t *b,
     ngx_http_chunked_t *ctx);
-ngx_chain_t *ngx_http_v3_create_header(ngx_http_request_t *r);
-ngx_chain_t *ngx_http_v3_create_trailers(ngx_http_request_t *r);
 
 uintptr_t ngx_http_v3_encode_varlen_int(u_char *p, uint64_t value);
 uintptr_t ngx_http_v3_encode_prefix_int(u_char *p, uint64_t value,
new file mode 100644
--- /dev/null
+++ b/src/http/v3/ngx_http_v3_filter_module.c
@@ -0,0 +1,1360 @@
+
+/*
+ * Copyright (C) Roman Arutyunyan
+ * Copyright (C) Nginx, Inc.
+ */
+
+
+#include <ngx_config.h>
+#include <ngx_core.h>
+#include <ngx_http.h>
+
+
+/* static table indices */
+#define NGX_HTTP_V3_HEADER_AUTHORITY                 0
+#define NGX_HTTP_V3_HEADER_PATH_ROOT                 1
+#define NGX_HTTP_V3_HEADER_CONTENT_LENGTH_ZERO       4
+#define NGX_HTTP_V3_HEADER_DATE                      6
+#define NGX_HTTP_V3_HEADER_LAST_MODIFIED             10
+#define NGX_HTTP_V3_HEADER_LOCATION                  12
+#define NGX_HTTP_V3_HEADER_METHOD_GET                17
+#define NGX_HTTP_V3_HEADER_SCHEME_HTTP               22
+#define NGX_HTTP_V3_HEADER_SCHEME_HTTPS              23
+#define NGX_HTTP_V3_HEADER_STATUS_200                25
+#define NGX_HTTP_V3_HEADER_ACCEPT_ENCODING           31
+#define NGX_HTTP_V3_HEADER_CONTENT_TYPE_TEXT_PLAIN   53
+#define NGX_HTTP_V3_HEADER_VARY_ACCEPT_ENCODING      59
+#define NGX_HTTP_V3_HEADER_ACCEPT_LANGUAGE           72
+#define NGX_HTTP_V3_HEADER_SERVER                    92
+#define NGX_HTTP_V3_HEADER_USER_AGENT                95
+
+
+typedef struct {
+    ngx_chain_t         *free;
+    ngx_chain_t         *busy;
+} ngx_http_v3_filter_ctx_t;
+
+
+static ngx_int_t ngx_http_v3_header_filter(ngx_http_request_t *r);
+static ngx_int_t ngx_http_v3_push_resources(ngx_http_request_t *r,
+    ngx_chain_t ***out);
+static ngx_int_t ngx_http_v3_push_resource(ngx_http_request_t *r,
+    ngx_str_t *path, ngx_chain_t ***out);
+static ngx_int_t ngx_http_v3_create_push_request(
+    ngx_http_request_t *pr, ngx_str_t *path, uint64_t push_id);
+static ngx_int_t ngx_http_v3_set_push_header(ngx_http_request_t *r,
+    const char *name, ngx_str_t *value);
+static void ngx_http_v3_push_request_handler(ngx_event_t *ev);
+static ngx_chain_t *ngx_http_v3_create_push_promise(ngx_http_request_t *r,
+    ngx_str_t *path, uint64_t push_id);
+static ngx_int_t ngx_http_v3_body_filter(ngx_http_request_t *r,
+    ngx_chain_t *in);
+static ngx_chain_t *ngx_http_v3_create_trailers(ngx_http_request_t *r);
+static ngx_int_t ngx_http_v3_filter_init(ngx_conf_t *cf);
+
+
+static ngx_http_module_t  ngx_http_v3_filter_module_ctx = {
+    NULL,                                  /* preconfiguration */
+    ngx_http_v3_filter_init,               /* postconfiguration */
+
+    NULL,                                  /* create main configuration */
+    NULL,                                  /* init main configuration */
+
+    NULL,                                  /* create server configuration */
+    NULL,                                  /* merge server configuration */
+
+    NULL,                                  /* create location configuration */
+    NULL                                   /* merge location configuration */
+};
+
+
+ngx_module_t  ngx_http_v3_filter_module = {
+    NGX_MODULE_V1,
+    &ngx_http_v3_filter_module_ctx,        /* module context */
+    NULL,                                  /* module directives */
+    NGX_HTTP_MODULE,                       /* module type */
+    NULL,                                  /* init master */
+    NULL,                                  /* init module */
+    NULL,                                  /* init process */
+    NULL,                                  /* init thread */
+    NULL,                                  /* exit thread */
+    NULL,                                  /* exit process */
+    NULL,                                  /* exit master */
+    NGX_MODULE_V1_PADDING
+};
+
+
+static ngx_http_output_header_filter_pt  ngx_http_next_header_filter;
+static ngx_http_output_body_filter_pt    ngx_http_next_body_filter;
+
+
+static ngx_int_t
+ngx_http_v3_header_filter(ngx_http_request_t *r)
+{
+    u_char                    *p;
+    size_t                     len, n;
+    ngx_buf_t                 *b;
+    ngx_str_t                  host;
+    ngx_uint_t                 i, port;
+    ngx_chain_t               *out, *hl, *cl, **ll;
+    ngx_list_part_t           *part;
+    ngx_table_elt_t           *header;
+    ngx_connection_t          *c;
+    ngx_http_v3_filter_ctx_t  *ctx;
+    ngx_http_core_loc_conf_t  *clcf;
+    ngx_http_core_srv_conf_t  *cscf;
+    u_char                     addr[NGX_SOCKADDR_STRLEN];
+
+    if (r->http_version != NGX_HTTP_VERSION_30) {
+        return ngx_http_next_header_filter(r);
+    }
+
+    if (r->header_sent) {
+        return NGX_OK;
+    }
+
+    r->header_sent = 1;
+
+    if (r != r->main) {
+        return NGX_OK;
+    }
+
+    if (r->method == NGX_HTTP_HEAD) {
+        r->header_only = 1;
+    }
+
+    if (r->headers_out.last_modified_time != -1) {
+        if (r->headers_out.status != NGX_HTTP_OK
+            && r->headers_out.status != NGX_HTTP_PARTIAL_CONTENT
+            && r->headers_out.status != NGX_HTTP_NOT_MODIFIED)
+        {
+            r->headers_out.last_modified_time = -1;
+            r->headers_out.last_modified = NULL;
+        }
+    }
+
+    if (r->headers_out.status == NGX_HTTP_NO_CONTENT) {
+        r->header_only = 1;
+        ngx_str_null(&r->headers_out.content_type);
+        r->headers_out.last_modified_time = -1;
+        r->headers_out.last_modified = NULL;
+        r->headers_out.content_length = NULL;
+        r->headers_out.content_length_n = -1;
+    }
+
+    if (r->headers_out.status == NGX_HTTP_NOT_MODIFIED) {
+        r->header_only = 1;
+    }
+
+    c = r->connection;
+
+    out = NULL;
+    ll = &out;
+
+    if ((c->quic->id & NGX_QUIC_STREAM_UNIDIRECTIONAL) == 0
+        && r->method != NGX_HTTP_HEAD)
+    {
+        if (ngx_http_v3_push_resources(r, &ll) != NGX_OK) {
+            return NGX_ERROR;
+        }
+    }
+
+    len = ngx_http_v3_encode_header_block_prefix(NULL, 0, 0, 0);
+
+    if (r->headers_out.status == NGX_HTTP_OK) {
+        len += ngx_http_v3_encode_header_ri(NULL, 0,
+                                            NGX_HTTP_V3_HEADER_STATUS_200);
+
+    } else {
+        len += ngx_http_v3_encode_header_lri(NULL, 0,
+                                             NGX_HTTP_V3_HEADER_STATUS_200,
+                                             NULL, 3);
+    }
+
+    clcf = ngx_http_get_module_loc_conf(r, ngx_http_core_module);
+
+    if (r->headers_out.server == NULL) {
+        if (clcf->server_tokens == NGX_HTTP_SERVER_TOKENS_ON) {
+            n = sizeof(NGINX_VER) - 1;
+
+        } else if (clcf->server_tokens == NGX_HTTP_SERVER_TOKENS_BUILD) {
+            n = sizeof(NGINX_VER_BUILD) - 1;
+
+        } else {
+            n = sizeof("nginx") - 1;
+        }
+
+        len += ngx_http_v3_encode_header_lri(NULL, 0,
+                                             NGX_HTTP_V3_HEADER_SERVER,
+                                             NULL, n);
+    }
+
+    if (r->headers_out.date == NULL) {
+        len += ngx_http_v3_encode_header_lri(NULL, 0, NGX_HTTP_V3_HEADER_DATE,
+                                             NULL, ngx_cached_http_time.len);
+    }
+
+    if (r->headers_out.content_type.len) {
+        n = r->headers_out.content_type.len;
+
+        if (r->headers_out.content_type_len == r->headers_out.content_type.len
+            && r->headers_out.charset.len)
+        {
+            n += sizeof("; charset=") - 1 + r->headers_out.charset.len;
+        }
+
+        len += ngx_http_v3_encode_header_lri(NULL, 0,
+                                    NGX_HTTP_V3_HEADER_CONTENT_TYPE_TEXT_PLAIN,
+                                    NULL, n);
+    }
+
+    if (r->headers_out.content_length == NULL) {
+        if (r->headers_out.content_length_n > 0) {
+            len += ngx_http_v3_encode_header_lri(NULL, 0,
+                                        NGX_HTTP_V3_HEADER_CONTENT_LENGTH_ZERO,
+                                        NULL, NGX_OFF_T_LEN);
+
+        } else if (r->headers_out.content_length_n == 0) {
+            len += ngx_http_v3_encode_header_ri(NULL, 0,
+                                       NGX_HTTP_V3_HEADER_CONTENT_LENGTH_ZERO);
+        }
+    }
+
+    if (r->headers_out.last_modified == NULL
+        && r->headers_out.last_modified_time != -1)
+    {
+        len += ngx_http_v3_encode_header_lri(NULL, 0,
+                                  NGX_HTTP_V3_HEADER_LAST_MODIFIED, NULL,
+                                  sizeof("Mon, 28 Sep 1970 06:00:00 GMT") - 1);
+    }
+
+    if (r->headers_out.location
+        && r->headers_out.location->value.len
+        && r->headers_out.location->value.data[0] == '/'
+        && clcf->absolute_redirect)
+    {
+        r->headers_out.location->hash = 0;
+
+        if (clcf->server_name_in_redirect) {
+            cscf = ngx_http_get_module_srv_conf(r, ngx_http_core_module);
+            host = cscf->server_name;
+
+        } else if (r->headers_in.server.len) {
+            host = r->headers_in.server;
+
+        } else {
+            host.len = NGX_SOCKADDR_STRLEN;
+            host.data = addr;
+
+            if (ngx_connection_local_sockaddr(c, &host, 0) != NGX_OK) {
+                return NGX_ERROR;
+            }
+        }
+
+        port = ngx_inet_get_port(c->local_sockaddr);
+
+        n = sizeof("https://") - 1 + host.len
+            + r->headers_out.location->value.len;
+
+        if (clcf->port_in_redirect) {
+            port = (port == 443) ? 0 : port;
+
+        } else {
+            port = 0;
+        }
+
+        if (port) {
+            n += sizeof(":65535") - 1;
+        }
+
+        len += ngx_http_v3_encode_header_lri(NULL, 0,
+                                         NGX_HTTP_V3_HEADER_LOCATION, NULL, n);
+
+    } else {
+        ngx_str_null(&host);
+        port = 0;
+    }
+
+#if (NGX_HTTP_GZIP)
+    if (r->gzip_vary) {
+        if (clcf->gzip_vary) {
+            len += ngx_http_v3_encode_header_ri(NULL, 0,
+                                      NGX_HTTP_V3_HEADER_VARY_ACCEPT_ENCODING);
+
+        } else {
+            r->gzip_vary = 0;
+        }
+    }
+#endif
+
+    part = &r->headers_out.headers.part;
+    header = part->elts;
+
+    for (i = 0; /* void */; i++) {
+
+        if (i >= part->nelts) {
+            if (part->next == NULL) {
+                break;
+            }
+
+            part = part->next;
+            header = part->elts;
+            i = 0;
+        }
+
+        if (header[i].hash == 0) {
+            continue;
+        }
+
+        len += ngx_http_v3_encode_header_l(NULL, &header[i].key,
+                                           &header[i].value);
+    }
+
+    ngx_log_debug1(NGX_LOG_DEBUG_HTTP, c->log, 0, "http3 header len:%uz", len);
+
+    b = ngx_create_temp_buf(r->pool, len);
+    if (b == NULL) {
+        return NGX_ERROR;
+    }
+
+    b->last = (u_char *) ngx_http_v3_encode_header_block_prefix(b->last,
+                                                                0, 0, 0);
+
+    if (r->headers_out.status == NGX_HTTP_OK) {
+        b->last = (u_char *) ngx_http_v3_encode_header_ri(b->last, 0,
+                                                NGX_HTTP_V3_HEADER_STATUS_200);
+
+    } else {
+        b->last = (u_char *) ngx_http_v3_encode_header_lri(b->last, 0,
+                                                 NGX_HTTP_V3_HEADER_STATUS_200,
+                                                 NULL, 3);
+        b->last = ngx_sprintf(b->last, "%03ui", r->headers_out.status);
+    }
+
+    if (r->headers_out.server == NULL) {
+        if (clcf->server_tokens == NGX_HTTP_SERVER_TOKENS_ON) {
+            p = (u_char *) NGINX_VER;
+            n = sizeof(NGINX_VER) - 1;
+
+        } else if (clcf->server_tokens == NGX_HTTP_SERVER_TOKENS_BUILD) {
+            p = (u_char *) NGINX_VER_BUILD;
+            n = sizeof(NGINX_VER_BUILD) - 1;
+
+        } else {
+            p = (u_char *) "nginx";
+            n = sizeof("nginx") - 1;
+        }
+
+        b->last = (u_char *) ngx_http_v3_encode_header_lri(b->last, 0,
+                                                     NGX_HTTP_V3_HEADER_SERVER,
+                                                     p, n);
+    }
+
+    if (r->headers_out.date == NULL) {
+        b->last = (u_char *) ngx_http_v3_encode_header_lri(b->last, 0,
+                                                     NGX_HTTP_V3_HEADER_DATE,
+                                                     ngx_cached_http_time.data,
+                                                     ngx_cached_http_time.len);
+    }
+
+    if (r->headers_out.content_type.len) {
+        n = r->headers_out.content_type.len;
+
+        if (r->headers_out.content_type_len == r->headers_out.content_type.len
+            && r->headers_out.charset.len)
+        {
+            n += sizeof("; charset=") - 1 + r->headers_out.charset.len;
+        }
+
+        b->last = (u_char *) ngx_http_v3_encode_header_lri(b->last, 0,
+                                    NGX_HTTP_V3_HEADER_CONTENT_TYPE_TEXT_PLAIN,
+                                    NULL, n);
+
+        p = b->last;
+        b->last = ngx_cpymem(b->last, r->headers_out.content_type.data,
+                             r->headers_out.content_type.len);
+
+        if (r->headers_out.content_type_len == r->headers_out.content_type.len
+            && r->headers_out.charset.len)
+        {
+            b->last = ngx_cpymem(b->last, "; charset=",
+                                 sizeof("; charset=") - 1);
+            b->last = ngx_cpymem(b->last, r->headers_out.charset.data,
+                                 r->headers_out.charset.len);
+
+            /* update r->headers_out.content_type for possible logging */
+
+            r->headers_out.content_type.len = b->last - p;
+            r->headers_out.content_type.data = p;
+        }
+    }
+
+    if (r->headers_out.content_length == NULL) {
+        if (r->headers_out.content_length_n > 0) {
+            p = ngx_sprintf(b->last, "%O", r->headers_out.content_length_n);
+            n = p - b->last;
+
+            b->last = (u_char *) ngx_http_v3_encode_header_lri(b->last, 0,
+                                        NGX_HTTP_V3_HEADER_CONTENT_LENGTH_ZERO,
+                                        NULL, n);
+
+            b->last = ngx_sprintf(b->last, "%O",
+                                  r->headers_out.content_length_n);
+
+        } else if (r->headers_out.content_length_n == 0) {
+            b->last = (u_char *) ngx_http_v3_encode_header_ri(b->last, 0,
+                                       NGX_HTTP_V3_HEADER_CONTENT_LENGTH_ZERO);
+        }
+    }
+
+    if (r->headers_out.last_modified == NULL
+        && r->headers_out.last_modified_time != -1)
+    {
+        b->last = (u_char *) ngx_http_v3_encode_header_lri(b->last, 0,
+                                  NGX_HTTP_V3_HEADER_LAST_MODIFIED, NULL,
+                                  sizeof("Mon, 28 Sep 1970 06:00:00 GMT") - 1);
+
+        b->last = ngx_http_time(b->last, r->headers_out.last_modified_time);
+    }
+
+    if (host.data) {
+        n = sizeof("https://") - 1 + host.len
+            + r->headers_out.location->value.len;
+
+        if (port) {
+            n += ngx_sprintf(b->last, ":%ui", port) - b->last;
+        }
+
+        b->last = (u_char *) ngx_http_v3_encode_header_lri(b->last, 0,
+                                                   NGX_HTTP_V3_HEADER_LOCATION,
+                                                   NULL, n);
+
+        p = b->last;
+        b->last = ngx_cpymem(b->last, "https://", sizeof("https://") - 1);
+        b->last = ngx_cpymem(b->last, host.data, host.len);
+
+        if (port) {
+            b->last = ngx_sprintf(b->last, ":%ui", port);
+        }
+
+        b->last = ngx_cpymem(b->last, r->headers_out.location->value.data,
+                             r->headers_out.location->value.len);
+
+        /* update r->headers_out.location->value for possible logging */
+
+        r->headers_out.location->value.len = b->last - p;
+        r->headers_out.location->value.data = p;
+        ngx_str_set(&r->headers_out.location->key, "Location");
+    }
+
+#if (NGX_HTTP_GZIP)
+    if (r->gzip_vary) {
+        b->last = (u_char *) ngx_http_v3_encode_header_ri(b->last, 0,
+                                      NGX_HTTP_V3_HEADER_VARY_ACCEPT_ENCODING);
+    }
+#endif
+
+    part = &r->headers_out.headers.part;
+    header = part->elts;
+
+    for (i = 0; /* void */; i++) {
+
+        if (i >= part->nelts) {
+            if (part->next == NULL) {
+                break;
+            }
+
+            part = part->next;
+            header = part->elts;
+            i = 0;
+        }
+
+        if (header[i].hash == 0) {
+            continue;
+        }
+
+        b->last = (u_char *) ngx_http_v3_encode_header_l(b->last,
+                                                         &header[i].key,
+                                                         &header[i].value);
+    }
+
+    if (r->header_only) {
+        b->last_buf = 1;
+    }
+
+    cl = ngx_alloc_chain_link(c->pool);
+    if (cl == NULL) {
+        return NGX_ERROR;
+    }
+
+    cl->buf = b;
+    cl->next = NULL;
+
+    n = b->last - b->pos;
+
+    len = ngx_http_v3_encode_varlen_int(NULL, NGX_HTTP_V3_FRAME_HEADERS)
+          + ngx_http_v3_encode_varlen_int(NULL, n);
+
+    b = ngx_create_temp_buf(c->pool, len);
+    if (b == NULL) {
+        return NGX_ERROR;
+    }
+
+    b->last = (u_char *) ngx_http_v3_encode_varlen_int(b->last,
+                                                    NGX_HTTP_V3_FRAME_HEADERS);
+    b->last = (u_char *) ngx_http_v3_encode_varlen_int(b->last, n);
+
+    hl = ngx_alloc_chain_link(c->pool);
+    if (hl == NULL) {
+        return NGX_ERROR;
+    }
+
+    hl->buf = b;
+    hl->next = cl;
+
+    *ll = hl;
+    ll = &cl->next;
+
+    if (r->headers_out.content_length_n >= 0 && !r->header_only) {
+        len = ngx_http_v3_encode_varlen_int(NULL, NGX_HTTP_V3_FRAME_DATA)
+              + ngx_http_v3_encode_varlen_int(NULL,
+                                              r->headers_out.content_length_n);
+
+        b = ngx_create_temp_buf(c->pool, len);
+        if (b == NULL) {
+            return NGX_ERROR;
+        }
+
+        b->last = (u_char *) ngx_http_v3_encode_varlen_int(b->last,
+                                                       NGX_HTTP_V3_FRAME_DATA);
+        b->last = (u_char *) ngx_http_v3_encode_varlen_int(b->last,
+                                              r->headers_out.content_length_n);
+
+        cl = ngx_alloc_chain_link(c->pool);
+        if (cl == NULL) {
+            return NGX_ERROR;
+        }
+
+        cl->buf = b;
+        cl->next = NULL;
+
+        *ll = cl;
+
+    } else {
+        ctx = ngx_pcalloc(r->pool, sizeof(ngx_http_v3_filter_ctx_t));
+        if (ctx == NULL) {
+            return NGX_ERROR;
+        }
+
+        ngx_http_set_ctx(r, ctx, ngx_http_v3_filter_module);
+    }
+
+    return ngx_http_write_filter(r, out);
+}
+
+
+static ngx_int_t
+ngx_http_v3_push_resources(ngx_http_request_t *r, ngx_chain_t ***out)
+{
+    u_char                     *start, *end, *last;
+    ngx_str_t                   path;
+    ngx_int_t                   rc;
+    ngx_uint_t                  i, push;
+    ngx_table_elt_t           **h;
+    ngx_http_v3_loc_conf_t     *h3lcf;
+    ngx_http_complex_value_t   *pushes;
+
+    h3lcf = ngx_http_get_module_loc_conf(r, ngx_http_v3_module);
+
+    if (h3lcf->pushes) {
+        pushes = h3lcf->pushes->elts;
+
+        for (i = 0; i < h3lcf->pushes->nelts; i++) {
+
+            if (ngx_http_complex_value(r, &pushes[i], &path) != NGX_OK) {
+                return NGX_ERROR;
+            }
+
+            if (path.len == 0) {
+                continue;
+            }
+
+            if (path.len == 3 && ngx_strncmp(path.data, "off", 3) == 0) {
+                continue;
+            }
+
+            rc = ngx_http_v3_push_resource(r, &path, out);
+
+            if (rc == NGX_ERROR) {
+                return NGX_ERROR;
+            }
+
+            if (rc == NGX_ABORT) {
+                return NGX_OK;
+            }
+
+            /* NGX_OK, NGX_DECLINED */
+        }
+    }
+
+    if (!h3lcf->push_preload) {
+        return NGX_OK;
+    }
+
+    h = r->headers_out.link.elts;
+
+    for (i = 0; i < r->headers_out.link.nelts; i++) {
+
+        ngx_log_debug1(NGX_LOG_DEBUG_HTTP, r->connection->log, 0,
+                       "http3 parse link: \"%V\"", &h[i]->value);
+
+        start = h[i]->value.data;
+        end = h[i]->value.data + h[i]->value.len;
+
+    next_link:
+
+        while (start < end && *start == ' ') { start++; }
+
+        if (start == end || *start++ != '<') {
+            continue;
+        }
+
+        while (start < end && *start == ' ') { start++; }
+
+        for (last = start; last < end && *last != '>'; last++) {
+            /* void */
+        }
+
+        if (last == start || last == end) {
+            continue;
+        }
+
+        path.len = last - start;
+        path.data = start;
+
+        start = last + 1;
+
+        while (start < end && *start == ' ') { start++; }
+
+        if (start == end) {
+            continue;
+        }
+
+        if (*start == ',') {
+            start++;
+            goto next_link;
+        }
+
+        if (*start++ != ';') {
+            continue;
+        }
+
+        last = ngx_strlchr(start, end, ',');
+
+        if (last == NULL) {
+            last = end;
+        }
+
+        push = 0;
+
+        for ( ;; ) {
+
+            while (start < last && *start == ' ') { start++; }
+
+            if (last - start >= 6
+                && ngx_strncasecmp(start, (u_char *) "nopush", 6) == 0)
+            {
+                start += 6;
+
+                if (start == last || *start == ' ' || *start == ';') {
+                    push = 0;
+                    break;
+                }
+
+                goto next_param;
+            }
+
+            if (last - start >= 11
+                && ngx_strncasecmp(start, (u_char *) "rel=preload", 11) == 0)
+            {
+                start += 11;
+
+                if (start == last || *start == ' ' || *start == ';') {
+                    push = 1;
+                }
+
+                goto next_param;
+            }
+
+            if (last - start >= 4
+                && ngx_strncasecmp(start, (u_char *) "rel=", 4) == 0)
+            {
+                start += 4;
+
+                while (start < last && *start == ' ') { start++; }
+
+                if (start == last || *start++ != '"') {
+                    goto next_param;
+                }
+
+                for ( ;; ) {
+
+                    while (start < last && *start == ' ') { start++; }
+
+                    if (last - start >= 7
+                        && ngx_strncasecmp(start, (u_char *) "preload", 7) == 0)
+                    {
+                        start += 7;
+
+                        if (start < last && (*start == ' ' || *start == '"')) {
+                            push = 1;
+                            break;
+                        }
+                    }
+
+                    while (start < last && *start != ' ' && *start != '"') {
+                        start++;
+                    }
+
+                    if (start == last) {
+                        break;
+                    }
+
+                    if (*start == '"') {
+                        break;
+                    }
+
+                    start++;
+                }
+            }
+
+        next_param:
+
+            start = ngx_strlchr(start, last, ';');
+
+            if (start == NULL) {
+                break;
+            }
+
+            start++;
+        }
+
+        if (push) {
+            while (path.len && path.data[path.len - 1] == ' ') {
+                path.len--;
+            }
+        }
+
+        if (push && path.len
+            && !(path.len > 1 && path.data[0] == '/' && path.data[1] == '/'))
+        {
+            rc = ngx_http_v3_push_resource(r, &path, out);
+
+            if (rc == NGX_ERROR) {
+                return NGX_ERROR;
+            }
+
+            if (rc == NGX_ABORT) {
+                return NGX_OK;
+            }
+
+            /* NGX_OK, NGX_DECLINED */
+        }
+
+        if (last < end) {
+            start = last + 1;
+            goto next_link;
+        }
+    }
+
+    return NGX_OK;
+}
+
+
+static ngx_int_t
+ngx_http_v3_push_resource(ngx_http_request_t *r, ngx_str_t *path,
+    ngx_chain_t ***ll)
+{
+    uint64_t                   push_id;
+    ngx_int_t                  rc;
+    ngx_chain_t               *cl;
+    ngx_connection_t          *c;
+    ngx_http_v3_srv_conf_t    *h3scf;
+    ngx_http_v3_connection_t  *h3c;
+
+    c = r->connection;
+    h3c = c->quic->parent->data;
+    h3scf = ngx_http_get_module_srv_conf(r, ngx_http_v3_module);
+
+    ngx_log_debug5(NGX_LOG_DEBUG_HTTP, c->log, 0,
+                   "http3 push \"%V\" pushing:%ui/%ui id:%uL/%uL",
+                   path, h3c->npushing, h3scf->max_concurrent_pushes,
+                   h3c->next_push_id, h3c->max_push_id);
+
+    if (!ngx_path_separator(path->data[0])) {
+        ngx_log_error(NGX_LOG_WARN, c->log, 0,
+                      "non-absolute path \"%V\" not pushed", path);
+        return NGX_DECLINED;
+    }
+
+    if (h3c->next_push_id > h3c->max_push_id) {
+        ngx_log_debug0(NGX_LOG_DEBUG_HTTP, c->log, 0,
+                       "http3 abort pushes due to max_push_id");
+        return NGX_ABORT;
+    }
+
+    if (h3c->npushing >= h3scf->max_concurrent_pushes) {
+        ngx_log_debug0(NGX_LOG_DEBUG_HTTP, c->log, 0,
+                       "http3 abort pushes due to max_concurrent_pushes");
+        return NGX_ABORT;
+    }
+
+    push_id = h3c->next_push_id++;
+
+    rc = ngx_http_v3_create_push_request(r, path, push_id);
+    if (rc != NGX_OK) {
+        return rc;
+    }
+
+    cl = ngx_http_v3_create_push_promise(r, path, push_id);
+    if (cl == NULL) {
+        return NGX_ERROR;
+    }
+
+    for (**ll = cl; **ll; *ll = &(**ll)->next);
+
+    return NGX_OK;
+}
+
+
+static ngx_int_t
+ngx_http_v3_create_push_request(ngx_http_request_t *pr, ngx_str_t *path,
+    uint64_t push_id)
+{
+    ngx_pool_t                *pool;
+    ngx_connection_t          *c, *pc;
+    ngx_http_request_t        *r;
+    ngx_http_log_ctx_t        *ctx;
+    ngx_http_connection_t     *hc;
+    ngx_http_core_srv_conf_t  *cscf;
+    ngx_http_v3_connection_t  *h3c;
+
+    pc = pr->connection;
+
+    r = NULL;
+
+    ngx_log_debug1(NGX_LOG_DEBUG_HTTP, pc->log, 0,
+                   "http3 create push request id:%uL", push_id);
+
+    c = ngx_http_v3_create_push_stream(pc, push_id);
+    if (c == NULL) {
+        return NGX_ABORT;
+    }
+
+    hc = ngx_palloc(c->pool, sizeof(ngx_http_connection_t));
+    if (hc == NULL) {
+        goto failed;
+    }
+
+    h3c = c->quic->parent->data;
+    ngx_memcpy(hc, h3c, sizeof(ngx_http_connection_t));
+    c->data = hc;
+
+    ctx = ngx_palloc(c->pool, sizeof(ngx_http_log_ctx_t));
+    if (ctx == NULL) {
+        goto failed;
+    }
+
+    ctx->connection = c;
+    ctx->request = NULL;
+    ctx->current_request = NULL;
+
+    c->log->handler = ngx_http_log_error;
+    c->log->data = ctx;
+    c->log->action = "processing pushed request headers";
+
+    c->log_error = NGX_ERROR_INFO;
+
+    r = ngx_http_create_request(c);
+    if (r == NULL) {
+        goto failed;
+    }
+
+    c->data = r;
+
+    ngx_str_set(&r->http_protocol, "HTTP/3.0");
+
+    r->method_name = ngx_http_core_get_method;
+    r->method = NGX_HTTP_GET;
+
+    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) {
+        goto failed;
+    }
+
+    if (ngx_list_init(&r->headers_in.headers, r->pool, 4,
+                      sizeof(ngx_table_elt_t))
+        != NGX_OK)
+    {
+        goto failed;
+    }
+
+    r->headers_in.connection_type = NGX_HTTP_CONNECTION_CLOSE;
+
+    r->schema.data = ngx_pstrdup(r->pool, &pr->schema);
+    if (r->schema.data == NULL) {
+        goto failed;
+    }
+
+    r->schema.len = pr->schema.len;
+
+    r->uri_start = ngx_pstrdup(r->pool, path);
+    if (r->uri_start == NULL) {
+        goto failed;
+    }
+
+    r->uri_end = r->uri_start + path->len;
+
+    if (ngx_http_parse_uri(r) != NGX_OK) {
+        goto failed;
+    }
+
+    if (ngx_http_process_request_uri(r) != NGX_OK) {
+        goto failed;
+    }
+
+    if (ngx_http_v3_set_push_header(r, "host", &pr->headers_in.server)
+        != NGX_OK)
+    {
+        goto failed;
+    }
+
+    if (pr->headers_in.accept_encoding) {
+        if (ngx_http_v3_set_push_header(r, "accept-encoding",
+                                        &pr->headers_in.accept_encoding->value)
+            != NGX_OK)
+        {
+            goto failed;
+        }
+    }
+
+    if (pr->headers_in.accept_language) {
+        if (ngx_http_v3_set_push_header(r, "accept-language",
+                                        &pr->headers_in.accept_language->value)
+            != NGX_OK)
+        {
+            goto failed;
+        }
+    }
+
+    if (pr->headers_in.user_agent) {
+        if (ngx_http_v3_set_push_header(r, "user-agent",
+                                        &pr->headers_in.user_agent->value)
+            != NGX_OK)
+        {
+            goto failed;
+        }
+    }
+
+    c->read->handler = ngx_http_v3_push_request_handler;
+    c->read->handler = ngx_http_v3_push_request_handler;
+
+    ngx_post_event(c->read, &ngx_posted_events);
+
+    return NGX_OK;
+
+failed:
+
+    if (r) {
+        ngx_http_free_request(r, NGX_HTTP_INTERNAL_SERVER_ERROR);
+    }
+
+    c->destroyed = 1;
+
+    pool = c->pool;
+
+    ngx_close_connection(c);
+
+    ngx_destroy_pool(pool);
+
+    return NGX_ERROR;
+}
+
+
+static ngx_int_t
+ngx_http_v3_set_push_header(ngx_http_request_t *r, const char *name,
+    ngx_str_t *value)
+{
+    u_char                     *p;
+    ngx_table_elt_t            *h;
+    ngx_http_header_t          *hh;
+    ngx_http_core_main_conf_t  *cmcf;
+
+    ngx_log_debug2(NGX_LOG_DEBUG_HTTP, r->connection->log, 0,
+                   "http3 push header \"%s\": \"%V\"", name, value);
+
+    cmcf = ngx_http_get_module_main_conf(r, ngx_http_core_module);
+
+    p = ngx_pnalloc(r->pool, value->len + 1);
+    if (p == NULL) {
+        return NGX_ERROR;
+    }
+
+    ngx_memcpy(p, value->data, value->len);
+    p[value->len] = '\0';
+
+    h = ngx_list_push(&r->headers_in.headers);
+    if (h == NULL) {
+        return NGX_ERROR;
+    }
+
+    h->key.data = (u_char *) name;
+    h->key.len = ngx_strlen(name);
+    h->hash = ngx_hash_key(h->key.data, h->key.len);
+    h->lowcase_key = (u_char *) name;
+    h->value.data = p;
+    h->value.len = value->len;
+
+    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) {
+        return NGX_ERROR;
+    }
+
+    return NGX_OK;
+}
+
+
+static void
+ngx_http_v3_push_request_handler(ngx_event_t *ev)
+{
+    ngx_connection_t    *c;
+    ngx_http_request_t  *r;
+
+    c = ev->data;
+    r = c->data;
+
+    ngx_log_debug0(NGX_LOG_DEBUG_HTTP, c->log, 0, "http3 push request handler");
+
+    ngx_http_process_request(r);
+}
+
+
+static ngx_chain_t *
+ngx_http_v3_create_push_promise(ngx_http_request_t *r, ngx_str_t *path,
+    uint64_t push_id)
+{
+    size_t        n, len;
+    ngx_buf_t    *b;
+    ngx_chain_t  *hl, *cl;
+
+    ngx_log_debug1(NGX_LOG_DEBUG_HTTP, r->connection->log, 0,
+                   "http3 create push promise id:%uL", push_id);
+
+    len = ngx_http_v3_encode_varlen_int(NULL, push_id);
+
+    len += ngx_http_v3_encode_header_block_prefix(NULL, 0, 0, 0);
+
+    len += ngx_http_v3_encode_header_ri(NULL, 0,
+                                        NGX_HTTP_V3_HEADER_METHOD_GET);
+
+    len += ngx_http_v3_encode_header_lri(NULL, 0,
+                                         NGX_HTTP_V3_HEADER_AUTHORITY,
+                                         NULL, r->headers_in.server.len);
+
+    if (path->len == 1 && path->data[0] == '/') {
+        len += ngx_http_v3_encode_header_ri(NULL, 0,
+                                            NGX_HTTP_V3_HEADER_PATH_ROOT);
+
+    } else {
+        len += ngx_http_v3_encode_header_lri(NULL, 0,
+                                             NGX_HTTP_V3_HEADER_PATH_ROOT,
+                                             NULL, path->len);
+    }
+
+    if (r->schema.len == 5 && ngx_strncmp(r->schema.data, "https", 5) == 0) {
+        len += ngx_http_v3_encode_header_ri(NULL, 0,
+                                            NGX_HTTP_V3_HEADER_SCHEME_HTTPS);
+
+    } else if (r->schema.len == 4
+               && ngx_strncmp(r->schema.data, "http", 4) == 0)
+    {
+        len += ngx_http_v3_encode_header_ri(NULL, 0,
+                                            NGX_HTTP_V3_HEADER_SCHEME_HTTP);
+
+    } else {
+        len += ngx_http_v3_encode_header_lri(NULL, 0,
+                                             NGX_HTTP_V3_HEADER_SCHEME_HTTP,
+                                             NULL, r->schema.len);
+    }
+
+    if (r->headers_in.accept_encoding) {
+        len += ngx_http_v3_encode_header_lri(NULL, 0,
+                                     NGX_HTTP_V3_HEADER_ACCEPT_ENCODING, NULL,
+                                     r->headers_in.accept_encoding->value.len);
+    }
+
+    if (r->headers_in.accept_language) {
+        len += ngx_http_v3_encode_header_lri(NULL, 0,
+                                     NGX_HTTP_V3_HEADER_ACCEPT_LANGUAGE, NULL,
+                                     r->headers_in.accept_language->value.len);
+    }
+
+    if (r->headers_in.user_agent) {
+        len += ngx_http_v3_encode_header_lri(NULL, 0,
+                                          NGX_HTTP_V3_HEADER_USER_AGENT, NULL,
+                                          r->headers_in.user_agent->value.len);
+    }
+
+    b = ngx_create_temp_buf(r->pool, len);
+    if (b == NULL) {
+        return NULL;
+    }
+
+    b->last = (u_char *) ngx_http_v3_encode_varlen_int(b->last, push_id);
+
+    b->last = (u_char *) ngx_http_v3_encode_header_block_prefix(b->last,
+                                                                0, 0, 0);
+
+    b->last = (u_char *) ngx_http_v3_encode_header_ri(b->last, 0,
+                                                NGX_HTTP_V3_HEADER_METHOD_GET);
+
+    b->last = (u_char *) ngx_http_v3_encode_header_lri(b->last, 0,
+                                                  NGX_HTTP_V3_HEADER_AUTHORITY,
+                                                  r->headers_in.server.data,
+                                                  r->headers_in.server.len);
+
+    if (path->len == 1 && path->data[0] == '/') {
+        b->last = (u_char *) ngx_http_v3_encode_header_ri(b->last, 0,
+                                                 NGX_HTTP_V3_HEADER_PATH_ROOT);
+
+    } else {
+        b->last = (u_char *) ngx_http_v3_encode_header_lri(b->last, 0,
+                                                  NGX_HTTP_V3_HEADER_PATH_ROOT,
+                                                  path->data, path->len);
+    }
+
+    if (r->schema.len == 5 && ngx_strncmp(r->schema.data, "https", 5) == 0) {
+        b->last = (u_char *) ngx_http_v3_encode_header_ri(b->last, 0,
+                                              NGX_HTTP_V3_HEADER_SCHEME_HTTPS);
+
+    } else if (r->schema.len == 4
+               && ngx_strncmp(r->schema.data, "http", 4) == 0)
+    {
+        b->last = (u_char *) ngx_http_v3_encode_header_ri(b->last, 0,
+                                               NGX_HTTP_V3_HEADER_SCHEME_HTTP);
+
+    } else {
+        b->last = (u_char *) ngx_http_v3_encode_header_lri(b->last, 0,
+                                                NGX_HTTP_V3_HEADER_SCHEME_HTTP,
+                                                r->schema.data, r->schema.len);
+    }
+
+    if (r->headers_in.accept_encoding) {
+        b->last = (u_char *) ngx_http_v3_encode_header_lri(b->last, 0,
+                                     NGX_HTTP_V3_HEADER_ACCEPT_ENCODING,
+                                     r->headers_in.accept_encoding->value.data,
+                                     r->headers_in.accept_encoding->value.len);
+    }
+
+    if (r->headers_in.accept_language) {
+        b->last = (u_char *) ngx_http_v3_encode_header_lri(b->last, 0,
+                                     NGX_HTTP_V3_HEADER_ACCEPT_LANGUAGE,
+                                     r->headers_in.accept_language->value.data,
+                                     r->headers_in.accept_language->value.len);
+    }
+
+    if (r->headers_in.user_agent) {
+        b->last = (u_char *) ngx_http_v3_encode_header_lri(b->last, 0,
+                                          NGX_HTTP_V3_HEADER_USER_AGENT,
+                                          r->headers_in.user_agent->value.data,
+                                          r->headers_in.user_agent->value.len);
+    }
+
+    cl = ngx_alloc_chain_link(r->pool);
+    if (cl == NULL) {
+        return NULL;
+    }
+
+    cl->buf = b;
+    cl->next = NULL;
+
+    n = b->last - b->pos;
+
+    len = ngx_http_v3_encode_varlen_int(NULL, NGX_HTTP_V3_FRAME_PUSH_PROMISE)
+          + ngx_http_v3_encode_varlen_int(NULL, n);
+
+    b = ngx_create_temp_buf(r->pool, len);
+    if (b == NULL) {
+        return NULL;
+    }
+
+    b->last = (u_char *) ngx_http_v3_encode_varlen_int(b->last,
+                                               NGX_HTTP_V3_FRAME_PUSH_PROMISE);
+    b->last = (u_char *) ngx_http_v3_encode_varlen_int(b->last, n);
+
+    hl = ngx_alloc_chain_link(r->pool);
+    if (hl == NULL) {
+        return NULL;
+    }
+
+    hl->buf = b;
+    hl->next = cl;
+
+    return hl;
+}
+
+
+static ngx_int_t
+ngx_http_v3_body_filter(ngx_http_request_t *r, ngx_chain_t *in)
+{
+    u_char                    *chunk;
+    off_t                      size;
+    ngx_int_t                  rc;
+    ngx_buf_t                 *b;
+    ngx_chain_t               *out, *cl, *tl, **ll;
+    ngx_http_v3_filter_ctx_t  *ctx;
+
+    if (in == NULL) {
+        return ngx_http_next_body_filter(r, in);
+    }
+
+    ctx = ngx_http_get_module_ctx(r, ngx_http_v3_filter_module);
+    if (ctx == NULL) {
+        return ngx_http_next_body_filter(r, in);
+    }
+
+    out = NULL;
+    ll = &out;
+
+    size = 0;
+    cl = in;
+
+    for ( ;; ) {
+        ngx_log_debug1(NGX_LOG_DEBUG_HTTP, r->connection->log, 0,
+                       "http3 chunk: %O", ngx_buf_size(cl->buf));
+
+        size += ngx_buf_size(cl->buf);
+
+        if (cl->buf->flush
+            || cl->buf->sync
+            || ngx_buf_in_memory(cl->buf)
+            || cl->buf->in_file)
+        {
+            tl = ngx_alloc_chain_link(r->pool);
+            if (tl == NULL) {
+                return NGX_ERROR;
+            }
+
+            tl->buf = cl->buf;
+            *ll = tl;
+            ll = &tl->next;
+        }
+
+        if (cl->next == NULL) {
+            break;
+        }
+
+        cl = cl->next;
+    }
+
+    if (size) {
+        tl = ngx_chain_get_free_buf(r->pool, &ctx->free);
+        if (tl == NULL) {
+            return NGX_ERROR;
+        }
+
+        b = tl->buf;
+        chunk = b->start;
+
+        if (chunk == NULL) {
+            chunk = ngx_palloc(r->pool, NGX_HTTP_V3_VARLEN_INT_LEN * 2);
+            if (chunk == NULL) {
+                return NGX_ERROR;
+            }
+
+            b->start = chunk;
+            b->end = chunk + NGX_HTTP_V3_VARLEN_INT_LEN * 2;
+        }
+
+        b->tag = (ngx_buf_tag_t) &ngx_http_v3_filter_module;
+        b->memory = 0;
+        b->temporary = 1;
+        b->pos = chunk;
+
+        b->last = (u_char *) ngx_http_v3_encode_varlen_int(chunk,
+                                                       NGX_HTTP_V3_FRAME_DATA);
+        b->last = (u_char *) ngx_http_v3_encode_varlen_int(b->last, size);
+
+        tl->next = out;
+        out = tl;
+    }
+
+    if (cl->buf->last_buf) {
+        tl = ngx_http_v3_create_trailers(r);
+        if (tl == NULL) {
+            return NGX_ERROR;
+        }
+
+        cl->buf->last_buf = 0;
+
+        *ll = tl;
+
+    } else {
+        *ll = NULL;
+    }
+
+    rc = ngx_http_next_body_filter(r, out);
+
+    ngx_chain_update_chains(r->pool, &ctx->free, &ctx->busy, &out,
+                            (ngx_buf_tag_t) &ngx_http_v3_filter_module);
+
+    return rc;
+}
+
+
+static ngx_chain_t *
+ngx_http_v3_create_trailers(ngx_http_request_t *r)
+{
+    ngx_buf_t    *b;
+    ngx_chain_t  *cl;
+
+    ngx_log_debug0(NGX_LOG_DEBUG_HTTP, r->connection->log, 0,
+                   "http3 create trailers");
+
+    /* XXX */
+
+    b = ngx_calloc_buf(r->pool);
+    if (b == NULL) {
+        return NULL;
+    }
+
+    b->last_buf = 1;
+
+    cl = ngx_alloc_chain_link(r->pool);
+    if (cl == NULL) {
+        return NULL;
+    }
+
+    cl->buf = b;
+    cl->next = NULL;
+
+    return cl;
+}
+
+
+static ngx_int_t
+ngx_http_v3_filter_init(ngx_conf_t *cf)
+{
+    ngx_http_next_header_filter = ngx_http_top_header_filter;
+    ngx_http_top_header_filter = ngx_http_v3_header_filter;
+
+    ngx_http_next_body_filter = ngx_http_top_body_filter;
+    ngx_http_top_body_filter = ngx_http_v3_body_filter;
+
+    return NGX_OK;
+}
--- a/src/http/v3/ngx_http_v3_request.c
+++ b/src/http/v3/ngx_http_v3_request.c
@@ -10,38 +10,8 @@
 #include <ngx_http.h>
 
 
-/* static table indices */
-#define NGX_HTTP_V3_HEADER_AUTHORITY                 0
-#define NGX_HTTP_V3_HEADER_PATH_ROOT                 1
-#define NGX_HTTP_V3_HEADER_CONTENT_LENGTH_ZERO       4
-#define NGX_HTTP_V3_HEADER_DATE                      6
-#define NGX_HTTP_V3_HEADER_LAST_MODIFIED             10
-#define NGX_HTTP_V3_HEADER_LOCATION                  12
-#define NGX_HTTP_V3_HEADER_METHOD_GET                17
-#define NGX_HTTP_V3_HEADER_SCHEME_HTTP               22
-#define NGX_HTTP_V3_HEADER_SCHEME_HTTPS              23
-#define NGX_HTTP_V3_HEADER_STATUS_200                25
-#define NGX_HTTP_V3_HEADER_ACCEPT_ENCODING           31
-#define NGX_HTTP_V3_HEADER_CONTENT_TYPE_TEXT_PLAIN   53
-#define NGX_HTTP_V3_HEADER_VARY_ACCEPT_ENCODING      59
-#define NGX_HTTP_V3_HEADER_ACCEPT_LANGUAGE           72
-#define NGX_HTTP_V3_HEADER_SERVER                    92
-#define NGX_HTTP_V3_HEADER_USER_AGENT                95
-
-
 static ngx_int_t ngx_http_v3_process_pseudo_header(ngx_http_request_t *r,
     ngx_str_t *name, ngx_str_t *value);
-static ngx_int_t ngx_http_v3_push_resources(ngx_http_request_t *r,
-    ngx_chain_t ***out);
-static ngx_int_t ngx_http_v3_push_resource(ngx_http_request_t *r,
-    ngx_str_t *path, ngx_chain_t ***out);
-static ngx_int_t ngx_http_v3_create_push_request(
-    ngx_http_request_t *pr, ngx_str_t *path, uint64_t push_id);
-static ngx_int_t ngx_http_v3_set_push_header(ngx_http_request_t *r,
-    const char *name, ngx_str_t *value);
-static void ngx_http_v3_push_request_handler(ngx_event_t *ev);
-static ngx_chain_t *ngx_http_v3_create_push_promise(ngx_http_request_t *r,
-    ngx_str_t *path, uint64_t push_id);
 
 
 struct {
@@ -443,1106 +413,3 @@ failed:
 
     return NGX_ERROR;
 }
-
-
-ngx_chain_t *
-ngx_http_v3_create_header(ngx_http_request_t *r)
-{
-    u_char                    *p;
-    size_t                     len, n;
-    ngx_buf_t                 *b;
-    ngx_str_t                  host;
-    ngx_uint_t                 i, port;
-    ngx_chain_t               *out, *hl, *cl, **ll;
-    ngx_list_part_t           *part;
-    ngx_table_elt_t           *header;
-    ngx_connection_t          *c;
-    ngx_http_core_loc_conf_t  *clcf;
-    ngx_http_core_srv_conf_t  *cscf;
-    u_char                     addr[NGX_SOCKADDR_STRLEN];
-
-    c = r->connection;
-
-    ngx_log_debug0(NGX_LOG_DEBUG_HTTP, c->log, 0, "http3 create header");
-
-    out = NULL;
-    ll = &out;
-
-    if ((c->quic->id & NGX_QUIC_STREAM_UNIDIRECTIONAL) == 0
-        && r->method != NGX_HTTP_HEAD)
-    {
-        if (ngx_http_v3_push_resources(r, &ll) != NGX_OK) {
-            return NULL;
-        }
-    }
-
-    len = ngx_http_v3_encode_header_block_prefix(NULL, 0, 0, 0);
-
-    if (r->headers_out.status == NGX_HTTP_OK) {
-        len += ngx_http_v3_encode_header_ri(NULL, 0,
-                                            NGX_HTTP_V3_HEADER_STATUS_200);
-
-    } else {
-        len += ngx_http_v3_encode_header_lri(NULL, 0,
-                                             NGX_HTTP_V3_HEADER_STATUS_200,
-                                             NULL, 3);
-    }
-
-    clcf = ngx_http_get_module_loc_conf(r, ngx_http_core_module);
-
-    if (r->headers_out.server == NULL) {
-        if (clcf->server_tokens == NGX_HTTP_SERVER_TOKENS_ON) {
-            n = sizeof(NGINX_VER) - 1;
-
-        } else if (clcf->server_tokens == NGX_HTTP_SERVER_TOKENS_BUILD) {
-            n = sizeof(NGINX_VER_BUILD) - 1;
-
-        } else {
-            n = sizeof("nginx") - 1;
-        }
-
-        len += ngx_http_v3_encode_header_lri(NULL, 0,
-                                             NGX_HTTP_V3_HEADER_SERVER,
-                                             NULL, n);
-    }
-
-    if (r->headers_out.date == NULL) {
-        len += ngx_http_v3_encode_header_lri(NULL, 0, NGX_HTTP_V3_HEADER_DATE,
-                                             NULL, ngx_cached_http_time.len);
-    }
-
-    if (r->headers_out.content_type.len) {
-        n = r->headers_out.content_type.len;
-
-        if (r->headers_out.content_type_len == r->headers_out.content_type.len
-            && r->headers_out.charset.len)
-        {
-            n += sizeof("; charset=") - 1 + r->headers_out.charset.len;
-        }
-
-        len += ngx_http_v3_encode_header_lri(NULL, 0,
-                                    NGX_HTTP_V3_HEADER_CONTENT_TYPE_TEXT_PLAIN,
-                                    NULL, n);
-    }
-
-    if (r->headers_out.content_length == NULL) {
-        if (r->headers_out.content_length_n > 0) {
-            len += ngx_http_v3_encode_header_lri(NULL, 0,
-                                        NGX_HTTP_V3_HEADER_CONTENT_LENGTH_ZERO,
-                                        NULL, NGX_OFF_T_LEN);
-
-        } else if (r->headers_out.content_length_n == 0) {
-            len += ngx_http_v3_encode_header_ri(NULL, 0,
-                                       NGX_HTTP_V3_HEADER_CONTENT_LENGTH_ZERO);
-        }
-    }
-
-    if (r->headers_out.last_modified == NULL
-        && r->headers_out.last_modified_time != -1)
-    {
-        len += ngx_http_v3_encode_header_lri(NULL, 0,
-                                  NGX_HTTP_V3_HEADER_LAST_MODIFIED, NULL,
-                                  sizeof("Mon, 28 Sep 1970 06:00:00 GMT") - 1);
-    }
-
-    if (r->headers_out.location
-        && r->headers_out.location->value.len
-        && r->headers_out.location->value.data[0] == '/'
-        && clcf->absolute_redirect)
-    {
-        r->headers_out.location->hash = 0;
-
-        if (clcf->server_name_in_redirect) {
-            cscf = ngx_http_get_module_srv_conf(r, ngx_http_core_module);
-            host = cscf->server_name;
-
-        } else if (r->headers_in.server.len) {
-            host = r->headers_in.server;
-
-        } else {
-            host.len = NGX_SOCKADDR_STRLEN;
-            host.data = addr;
-
-            if (ngx_connection_local_sockaddr(c, &host, 0) != NGX_OK) {
-                return NULL;
-            }
-        }
-
-        port = ngx_inet_get_port(c->local_sockaddr);
-
-        n = sizeof("https://") - 1 + host.len
-            + r->headers_out.location->value.len;
-
-        if (clcf->port_in_redirect) {
-            port = (port == 443) ? 0 : port;
-
-        } else {
-            port = 0;
-        }
-
-        if (port) {
-            n += sizeof(":65535") - 1;
-        }
-
-        len += ngx_http_v3_encode_header_lri(NULL, 0,
-                                         NGX_HTTP_V3_HEADER_LOCATION, NULL, n);
-
-    } else {
-        ngx_str_null(&host);
-        port = 0;
-    }
-
-#if (NGX_HTTP_GZIP)
-    if (r->gzip_vary) {
-        if (clcf->gzip_vary) {
-            len += ngx_http_v3_encode_header_ri(NULL, 0,
-                                      NGX_HTTP_V3_HEADER_VARY_ACCEPT_ENCODING);
-
-        } else {
-            r->gzip_vary = 0;
-        }
-    }
-#endif
-
-    part = &r->headers_out.headers.part;
-    header = part->elts;
-
-    for (i = 0; /* void */; i++) {
-
-        if (i >= part->nelts) {
-            if (part->next == NULL) {
-                break;
-            }
-
-            part = part->next;
-            header = part->elts;
-            i = 0;
-        }
-
-        if (header[i].hash == 0) {
-            continue;
-        }
-
-        len += ngx_http_v3_encode_header_l(NULL, &header[i].key,
-                                           &header[i].value);
-    }
-
-    ngx_log_debug1(NGX_LOG_DEBUG_HTTP, c->log, 0, "http3 header len:%uz", len);
-
-    b = ngx_create_temp_buf(r->pool, len);
-    if (b == NULL) {
-        return NULL;
-    }
-
-    b->last = (u_char *) ngx_http_v3_encode_header_block_prefix(b->last,
-                                                                0, 0, 0);
-
-    if (r->headers_out.status == NGX_HTTP_OK) {
-        b->last = (u_char *) ngx_http_v3_encode_header_ri(b->last, 0,
-                                                NGX_HTTP_V3_HEADER_STATUS_200);
-
-    } else {
-        b->last = (u_char *) ngx_http_v3_encode_header_lri(b->last, 0,
-                                                 NGX_HTTP_V3_HEADER_STATUS_200,
-                                                 NULL, 3);
-        b->last = ngx_sprintf(b->last, "%03ui", r->headers_out.status);
-    }
-
-    if (r->headers_out.server == NULL) {
-        if (clcf->server_tokens == NGX_HTTP_SERVER_TOKENS_ON) {
-            p = (u_char *) NGINX_VER;
-            n = sizeof(NGINX_VER) - 1;
-
-        } else if (clcf->server_tokens == NGX_HTTP_SERVER_TOKENS_BUILD) {
-            p = (u_char *) NGINX_VER_BUILD;
-            n = sizeof(NGINX_VER_BUILD) - 1;
-
-        } else {
-            p = (u_char *) "nginx";
-            n = sizeof("nginx") - 1;
-        }
-
-        b->last = (u_char *) ngx_http_v3_encode_header_lri(b->last, 0,
-                                                     NGX_HTTP_V3_HEADER_SERVER,
-                                                     p, n);
-    }
-
-    if (r->headers_out.date == NULL) {
-        b->last = (u_char *) ngx_http_v3_encode_header_lri(b->last, 0,
-                                                     NGX_HTTP_V3_HEADER_DATE,
-                                                     ngx_cached_http_time.data,
-                                                     ngx_cached_http_time.len);
-    }
-
-    if (r->headers_out.content_type.len) {
-        n = r->headers_out.content_type.len;
-
-        if (r->headers_out.content_type_len == r->headers_out.content_type.len
-            && r->headers_out.charset.len)
-        {
-            n += sizeof("; charset=") - 1 + r->headers_out.charset.len;
-        }
-
-        b->last = (u_char *) ngx_http_v3_encode_header_lri(b->last, 0,
-                                    NGX_HTTP_V3_HEADER_CONTENT_TYPE_TEXT_PLAIN,
-                                    NULL, n);
-
-        p = b->last;
-        b->last = ngx_cpymem(b->last, r->headers_out.content_type.data,
-                             r->headers_out.content_type.len);
-
-        if (r->headers_out.content_type_len == r->headers_out.content_type.len
-            && r->headers_out.charset.len)
-        {
-            b->last = ngx_cpymem(b->last, "; charset=",
-                                 sizeof("; charset=") - 1);
-            b->last = ngx_cpymem(b->last, r->headers_out.charset.data,
-                                 r->headers_out.charset.len);
-
-            /* update r->headers_out.content_type for possible logging */
-
-            r->headers_out.content_type.len = b->last - p;
-            r->headers_out.content_type.data = p;
-        }
-    }
-
-    if (r->headers_out.content_length == NULL) {
-        if (r->headers_out.content_length_n > 0) {
-            p = ngx_sprintf(b->last, "%O", r->headers_out.content_length_n);
-            n = p - b->last;
-
-            b->last = (u_char *) ngx_http_v3_encode_header_lri(b->last, 0,
-                                        NGX_HTTP_V3_HEADER_CONTENT_LENGTH_ZERO,
-                                        NULL, n);
-
-            b->last = ngx_sprintf(b->last, "%O",
-                                  r->headers_out.content_length_n);
-
-        } else if (r->headers_out.content_length_n == 0) {
-            b->last = (u_char *) ngx_http_v3_encode_header_ri(b->last, 0,
-                                       NGX_HTTP_V3_HEADER_CONTENT_LENGTH_ZERO);
-        }
-    }
-
-    if (r->headers_out.last_modified == NULL
-        && r->headers_out.last_modified_time != -1)
-    {
-        b->last = (u_char *) ngx_http_v3_encode_header_lri(b->last, 0,
-                                  NGX_HTTP_V3_HEADER_LAST_MODIFIED, NULL,
-                                  sizeof("Mon, 28 Sep 1970 06:00:00 GMT") - 1);
-
-        b->last = ngx_http_time(b->last, r->headers_out.last_modified_time);
-    }
-
-    if (host.data) {
-        n = sizeof("https://") - 1 + host.len
-            + r->headers_out.location->value.len;
-
-        if (port) {
-            n += ngx_sprintf(b->last, ":%ui", port) - b->last;
-        }
-
-        b->last = (u_char *) ngx_http_v3_encode_header_lri(b->last, 0,
-                                                   NGX_HTTP_V3_HEADER_LOCATION,
-                                                   NULL, n);
-
-        p = b->last;
-        b->last = ngx_cpymem(b->last, "https://", sizeof("https://") - 1);
-        b->last = ngx_cpymem(b->last, host.data, host.len);
-
-        if (port) {
-            b->last = ngx_sprintf(b->last, ":%ui", port);
-        }
-
-        b->last = ngx_cpymem(b->last, r->headers_out.location->value.data,
-                             r->headers_out.location->value.len);
-
-        /* update r->headers_out.location->value for possible logging */
-
-        r->headers_out.location->value.len = b->last - p;
-        r->headers_out.location->value.data = p;
-        ngx_str_set(&r->headers_out.location->key, "Location");
-    }
-
-#if (NGX_HTTP_GZIP)
-    if (r->gzip_vary) {
-        b->last = (u_char *) ngx_http_v3_encode_header_ri(b->last, 0,
-                                      NGX_HTTP_V3_HEADER_VARY_ACCEPT_ENCODING);
-    }
-#endif
-
-    part = &r->headers_out.headers.part;
-    header = part->elts;
-
-    for (i = 0; /* void */; i++) {
-
-        if (i >= part->nelts) {
-            if (part->next == NULL) {
-                break;
-            }
-
-            part = part->next;
-            header = part->elts;
-            i = 0;
-        }
-
-        if (header[i].hash == 0) {
-            continue;
-        }
-
-        b->last = (u_char *) ngx_http_v3_encode_header_l(b->last,
-                                                         &header[i].key,
-                                                         &header[i].value);
-    }
-
-    if (r->header_only) {
-        b->last_buf = 1;
-    }
-
-    cl = ngx_alloc_chain_link(c->pool);
-    if (cl == NULL) {
-        return NULL;
-    }
-
-    cl->buf = b;
-    cl->next = NULL;
-
-    n = b->last - b->pos;
-
-    len = ngx_http_v3_encode_varlen_int(NULL, NGX_HTTP_V3_FRAME_HEADERS)
-          + ngx_http_v3_encode_varlen_int(NULL, n);
-
-    b = ngx_create_temp_buf(c->pool, len);
-    if (b == NULL) {
-        return NULL;
-    }
-
-    b->last = (u_char *) ngx_http_v3_encode_varlen_int(b->last,
-                                                    NGX_HTTP_V3_FRAME_HEADERS);
-    b->last = (u_char *) ngx_http_v3_encode_varlen_int(b->last, n);
-
-    hl = ngx_alloc_chain_link(c->pool);
-    if (hl == NULL) {
-        return NULL;
-    }
-
-    hl->buf = b;
-    hl->next = cl;
-
-    *ll = hl;
-    ll = &cl->next;
-
-    if (r->headers_out.content_length_n >= 0 && !r->header_only) {
-        len = ngx_http_v3_encode_varlen_int(NULL, NGX_HTTP_V3_FRAME_DATA)
-              + ngx_http_v3_encode_varlen_int(NULL,
-                                              r->headers_out.content_length_n);
-
-        b = ngx_create_temp_buf(c->pool, len);
-        if (b == NULL) {
-            return NULL;
-        }
-
-        b->last = (u_char *) ngx_http_v3_encode_varlen_int(b->last,
-                                                       NGX_HTTP_V3_FRAME_DATA);
-        b->last = (u_char *) ngx_http_v3_encode_varlen_int(b->last,
-                                              r->headers_out.content_length_n);
-
-        cl = ngx_alloc_chain_link(c->pool);
-        if (cl == NULL) {
-            return NULL;
-        }
-
-        cl->buf = b;
-        cl->next = NULL;
-
-        *ll = cl;
-    }
-
-    return out;
-}
-
-
-ngx_chain_t *
-ngx_http_v3_create_trailers(ngx_http_request_t *r)
-{
-    ngx_buf_t    *b;
-    ngx_chain_t  *cl;
-
-    ngx_log_debug0(NGX_LOG_DEBUG_HTTP, r->connection->log, 0,
-                   "http3 create trailers");
-
-    /* XXX */
-
-    b = ngx_calloc_buf(r->pool);
-    if (b == NULL) {
-        return NULL;
-    }
-
-    b->last_buf = 1;
-
-    cl = ngx_alloc_chain_link(r->pool);
-    if (cl == NULL) {
-        return NULL;
-    }
-
-    cl->buf = b;
-    cl->next = NULL;
-
-    return cl;
-}
-
-
-static ngx_int_t
-ngx_http_v3_push_resources(ngx_http_request_t *r, ngx_chain_t ***out)
-{
-    u_char                     *start, *end, *last;
-    ngx_str_t                   path;
-    ngx_int_t                   rc;
-    ngx_uint_t                  i, push;
-    ngx_table_elt_t           **h;
-    ngx_http_v3_loc_conf_t     *h3lcf;
-    ngx_http_complex_value_t   *pushes;
-
-    h3lcf = ngx_http_get_module_loc_conf(r, ngx_http_v3_module);
-
-    if (h3lcf->pushes) {
-        pushes = h3lcf->pushes->elts;
-
-        for (i = 0; i < h3lcf->pushes->nelts; i++) {
-
-            if (ngx_http_complex_value(r, &pushes[i], &path) != NGX_OK) {
-                return NGX_ERROR;
-            }
-
-            if (path.len == 0) {
-                continue;
-            }
-
-            if (path.len == 3 && ngx_strncmp(path.data, "off", 3) == 0) {
-                continue;
-            }
-
-            rc = ngx_http_v3_push_resource(r, &path, out);
-
-            if (rc == NGX_ERROR) {
-                return NGX_ERROR;
-            }
-
-            if (rc == NGX_ABORT) {
-                return NGX_OK;
-            }
-
-            /* NGX_OK, NGX_DECLINED */
-        }
-    }
-
-    if (!h3lcf->push_preload) {
-        return NGX_OK;
-    }
-
-    h = r->headers_out.link.elts;
-
-    for (i = 0; i < r->headers_out.link.nelts; i++) {
-
-        ngx_log_debug1(NGX_LOG_DEBUG_HTTP, r->connection->log, 0,
-                       "http3 parse link: \"%V\"", &h[i]->value);
-
-        start = h[i]->value.data;
-        end = h[i]->value.data + h[i]->value.len;
-
-    next_link:
-
-        while (start < end && *start == ' ') { start++; }
-
-        if (start == end || *start++ != '<') {
-            continue;
-        }
-
-        while (start < end && *start == ' ') { start++; }
-
-        for (last = start; last < end && *last != '>'; last++) {
-            /* void */
-        }
-
-        if (last == start || last == end) {
-            continue;
-        }
-
-        path.len = last - start;
-        path.data = start;
-
-        start = last + 1;
-
-        while (start < end && *start == ' ') { start++; }
-
-        if (start == end) {
-            continue;
-        }
-
-        if (*start == ',') {
-            start++;
-            goto next_link;
-        }
-
-        if (*start++ != ';') {
-            continue;
-        }
-
-        last = ngx_strlchr(start, end, ',');
-
-        if (last == NULL) {
-            last = end;
-        }
-
-        push = 0;
-
-        for ( ;; ) {
-
-            while (start < last && *start == ' ') { start++; }
-
-            if (last - start >= 6
-                && ngx_strncasecmp(start, (u_char *) "nopush", 6) == 0)
-            {
-                start += 6;
-
-                if (start == last || *start == ' ' || *start == ';') {
-                    push = 0;
-                    break;
-                }
-
-                goto next_param;
-            }
-
-            if (last - start >= 11
-                && ngx_strncasecmp(start, (u_char *) "rel=preload", 11) == 0)
-            {
-                start += 11;
-
-                if (start == last || *start == ' ' || *start == ';') {
-                    push = 1;
-                }
-
-                goto next_param;
-            }
-
-            if (last - start >= 4
-                && ngx_strncasecmp(start, (u_char *) "rel=", 4) == 0)
-            {
-                start += 4;
-
-                while (start < last && *start == ' ') { start++; }
-
-                if (start == last || *start++ != '"') {
-                    goto next_param;
-                }
-
-                for ( ;; ) {
-
-                    while (start < last && *start == ' ') { start++; }
-
-                    if (last - start >= 7
-                        && ngx_strncasecmp(start, (u_char *) "preload", 7) == 0)
-                    {
-                        start += 7;
-
-                        if (start < last && (*start == ' ' || *start == '"')) {
-                            push = 1;
-                            break;
-                        }
-                    }
-
-                    while (start < last && *start != ' ' && *start != '"') {
-                        start++;
-                    }
-
-                    if (start == last) {
-                        break;
-                    }
-
-                    if (*start == '"') {
-                        break;
-                    }
-
-                    start++;
-                }
-            }
-
-        next_param:
-
-            start = ngx_strlchr(start, last, ';');
-
-            if (start == NULL) {
-                break;
-            }
-
-            start++;
-        }
-
-        if (push) {
-            while (path.len && path.data[path.len - 1] == ' ') {
-                path.len--;
-            }
-        }
-
-        if (push && path.len
-            && !(path.len > 1 && path.data[0] == '/' && path.data[1] == '/'))
-        {
-            rc = ngx_http_v3_push_resource(r, &path, out);
-
-            if (rc == NGX_ERROR) {
-                return NGX_ERROR;
-            }
-
-            if (rc == NGX_ABORT) {
-                return NGX_OK;
-            }
-
-            /* NGX_OK, NGX_DECLINED */
-        }
-
-        if (last < end) {
-            start = last + 1;
-            goto next_link;
-        }
-    }
-
-    return NGX_OK;
-}
-
-
-static ngx_int_t
-ngx_http_v3_push_resource(ngx_http_request_t *r, ngx_str_t *path,
-    ngx_chain_t ***ll)
-{
-    uint64_t                   push_id;
-    ngx_int_t                  rc;
-    ngx_chain_t               *cl;
-    ngx_connection_t          *c;
-    ngx_http_v3_srv_conf_t    *h3scf;
-    ngx_http_v3_connection_t  *h3c;
-
-    c = r->connection;
-    h3c = c->quic->parent->data;
-    h3scf = ngx_http_get_module_srv_conf(r, ngx_http_v3_module);
-
-    ngx_log_debug5(NGX_LOG_DEBUG_HTTP, c->log, 0,
-                   "http3 push \"%V\" pushing:%ui/%ui id:%uL/%uL",
-                   path, h3c->npushing, h3scf->max_concurrent_pushes,
-                   h3c->next_push_id, h3c->max_push_id);
-
-    if (!ngx_path_separator(path->data[0])) {
-        ngx_log_error(NGX_LOG_WARN, c->log, 0,
-                      "non-absolute path \"%V\" not pushed", path);
-        return NGX_DECLINED;
-    }
-
-    if (h3c->next_push_id > h3c->max_push_id) {
-        ngx_log_debug0(NGX_LOG_DEBUG_HTTP, c->log, 0,
-                       "http3 abort pushes due to max_push_id");
-        return NGX_ABORT;
-    }
-
-    if (h3c->npushing >= h3scf->max_concurrent_pushes) {
-        ngx_log_debug0(NGX_LOG_DEBUG_HTTP, c->log, 0,
-                       "http3 abort pushes due to max_concurrent_pushes");
-        return NGX_ABORT;
-    }
-
-    push_id = h3c->next_push_id++;
-
-    rc = ngx_http_v3_create_push_request(r, path, push_id);
-    if (rc != NGX_OK) {
-        return rc;
-    }
-
-    cl = ngx_http_v3_create_push_promise(r, path, push_id);
-    if (cl == NULL) {
-        return NGX_ERROR;
-    }
-
-    for (**ll = cl; **ll; *ll = &(**ll)->next);
-
-    return NGX_OK;
-}
-
-
-static ngx_int_t
-ngx_http_v3_create_push_request(ngx_http_request_t *pr, ngx_str_t *path,
-    uint64_t push_id)
-{
-    ngx_pool_t                *pool;
-    ngx_connection_t          *c, *pc;
-    ngx_http_request_t        *r;
-    ngx_http_log_ctx_t        *ctx;
-    ngx_http_connection_t     *hc;
-    ngx_http_core_srv_conf_t  *cscf;
-    ngx_http_v3_connection_t  *h3c;
-
-    pc = pr->connection;
-
-    r = NULL;
-
-    ngx_log_debug1(NGX_LOG_DEBUG_HTTP, pc->log, 0,
-                   "http3 create push request id:%uL", push_id);
-
-    c = ngx_http_v3_create_push_stream(pc, push_id);
-    if (c == NULL) {
-        return NGX_ABORT;
-    }
-
-    hc = ngx_palloc(c->pool, sizeof(ngx_http_connection_t));
-    if (hc == NULL) {
-        goto failed;
-    }
-
-    h3c = c->quic->parent->data;
-    ngx_memcpy(hc, h3c, sizeof(ngx_http_connection_t));
-    c->data = hc;
-
-    ctx = ngx_palloc(c->pool, sizeof(ngx_http_log_ctx_t));
-    if (ctx == NULL) {
-        goto failed;
-    }
-
-    ctx->connection = c;
-    ctx->request = NULL;
-    ctx->current_request = NULL;
-
-    c->log->handler = ngx_http_log_error;
-    c->log->data = ctx;
-    c->log->action = "processing pushed request headers";
-
-    c->log_error = NGX_ERROR_INFO;
-
-    r = ngx_http_create_request(c);
-    if (r == NULL) {
-        goto failed;
-    }
-
-    c->data = r;
-
-    ngx_str_set(&r->http_protocol, "HTTP/3.0");
-
-    r->method_name = ngx_http_core_get_method;
-    r->method = NGX_HTTP_GET;
-
-    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) {
-        goto failed;
-    }
-
-    if (ngx_list_init(&r->headers_in.headers, r->pool, 4,
-                      sizeof(ngx_table_elt_t))
-        != NGX_OK)
-    {
-        goto failed;
-    }
-
-    r->headers_in.connection_type = NGX_HTTP_CONNECTION_CLOSE;
-
-    r->schema.data = ngx_pstrdup(r->pool, &pr->schema);
-    if (r->schema.data == NULL) {
-        goto failed;
-    }
-
-    r->schema.len = pr->schema.len;
-
-    r->uri_start = ngx_pstrdup(r->pool, path);
-    if (r->uri_start == NULL) {
-        goto failed;
-    }
-
-    r->uri_end = r->uri_start + path->len;
-
-    if (ngx_http_parse_uri(r) != NGX_OK) {
-        goto failed;
-    }
-
-    if (ngx_http_process_request_uri(r) != NGX_OK) {
-        goto failed;
-    }
-
-    if (ngx_http_v3_set_push_header(r, "host", &pr->headers_in.server)
-        != NGX_OK)
-    {
-        goto failed;
-    }
-
-    if (pr->headers_in.accept_encoding) {
-        if (ngx_http_v3_set_push_header(r, "accept-encoding",
-                                        &pr->headers_in.accept_encoding->value)
-            != NGX_OK)
-        {
-            goto failed;
-        }
-    }
-
-    if (pr->headers_in.accept_language) {
-        if (ngx_http_v3_set_push_header(r, "accept-language",
-                                        &pr->headers_in.accept_language->value)
-            != NGX_OK)
-        {
-            goto failed;
-        }
-    }
-
-    if (pr->headers_in.user_agent) {
-        if (ngx_http_v3_set_push_header(r, "user-agent",
-                                        &pr->headers_in.user_agent->value)
-            != NGX_OK)
-        {
-            goto failed;
-        }
-    }
-
-    c->read->handler = ngx_http_v3_push_request_handler;
-    c->read->handler = ngx_http_v3_push_request_handler;
-
-    ngx_post_event(c->read, &ngx_posted_events);
-
-    return NGX_OK;
-
-failed:
-
-    if (r) {
-        ngx_http_free_request(r, NGX_HTTP_INTERNAL_SERVER_ERROR);
-    }
-
-    c->destroyed = 1;
-
-    pool = c->pool;
-
-    ngx_close_connection(c);
-
-    ngx_destroy_pool(pool);
-
-    return NGX_ERROR;
-}
-
-
-static ngx_int_t
-ngx_http_v3_set_push_header(ngx_http_request_t *r, const char *name,
-    ngx_str_t *value)
-{
-    u_char                     *p;
-    ngx_table_elt_t            *h;
-    ngx_http_header_t          *hh;
-    ngx_http_core_main_conf_t  *cmcf;
-
-    ngx_log_debug2(NGX_LOG_DEBUG_HTTP, r->connection->log, 0,
-                   "http3 push header \"%s\": \"%V\"", name, value);
-
-    cmcf = ngx_http_get_module_main_conf(r, ngx_http_core_module);
-
-    p = ngx_pnalloc(r->pool, value->len + 1);
-    if (p == NULL) {
-        return NGX_ERROR;
-    }
-
-    ngx_memcpy(p, value->data, value->len);
-    p[value->len] = '\0';
-
-    h = ngx_list_push(&r->headers_in.headers);
-    if (h == NULL) {
-        return NGX_ERROR;
-    }
-
-    h->key.data = (u_char *) name;
-    h->key.len = ngx_strlen(name);
-    h->hash = ngx_hash_key(h->key.data, h->key.len);
-    h->lowcase_key = (u_char *) name;
-    h->value.data = p;
-    h->value.len = value->len;
-
-    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) {
-        return NGX_ERROR;
-    }
-
-    return NGX_OK;
-}
-
-
-static void
-ngx_http_v3_push_request_handler(ngx_event_t *ev)
-{
-    ngx_connection_t    *c;
-    ngx_http_request_t  *r;
-
-    c = ev->data;
-    r = c->data;
-
-    ngx_log_debug0(NGX_LOG_DEBUG_HTTP, c->log, 0, "http3 push request handler");
-
-    ngx_http_process_request(r);
-}
-
-
-static ngx_chain_t *
-ngx_http_v3_create_push_promise(ngx_http_request_t *r, ngx_str_t *path,
-    uint64_t push_id)
-{
-    size_t        n, len;
-    ngx_buf_t    *b;
-    ngx_chain_t  *hl, *cl;
-
-    ngx_log_debug1(NGX_LOG_DEBUG_HTTP, r->connection->log, 0,
-                   "http3 create push promise id:%uL", push_id);
-
-    len = ngx_http_v3_encode_varlen_int(NULL, push_id);
-
-    len += ngx_http_v3_encode_header_block_prefix(NULL, 0, 0, 0);
-
-    len += ngx_http_v3_encode_header_ri(NULL, 0,
-                                        NGX_HTTP_V3_HEADER_METHOD_GET);
-
-    len += ngx_http_v3_encode_header_lri(NULL, 0,
-                                         NGX_HTTP_V3_HEADER_AUTHORITY,
-                                         NULL, r->headers_in.server.len);
-
-    if (path->len == 1 && path->data[0] == '/') {
-        len += ngx_http_v3_encode_header_ri(NULL, 0,
-                                            NGX_HTTP_V3_HEADER_PATH_ROOT);
-
-    } else {
-        len += ngx_http_v3_encode_header_lri(NULL, 0,
-                                             NGX_HTTP_V3_HEADER_PATH_ROOT,
-                                             NULL, path->len);
-    }
-
-    if (r->schema.len == 5 && ngx_strncmp(r->schema.data, "https", 5) == 0) {
-        len += ngx_http_v3_encode_header_ri(NULL, 0,
-                                            NGX_HTTP_V3_HEADER_SCHEME_HTTPS);
-
-    } else if (r->schema.len == 4
-               && ngx_strncmp(r->schema.data, "http", 4) == 0)
-    {
-        len += ngx_http_v3_encode_header_ri(NULL, 0,
-                                            NGX_HTTP_V3_HEADER_SCHEME_HTTP);
-
-    } else {
-        len += ngx_http_v3_encode_header_lri(NULL, 0,
-                                             NGX_HTTP_V3_HEADER_SCHEME_HTTP,
-                                             NULL, r->schema.len);
-    }
-
-    if (r->headers_in.accept_encoding) {
-        len += ngx_http_v3_encode_header_lri(NULL, 0,
-                                     NGX_HTTP_V3_HEADER_ACCEPT_ENCODING, NULL,
-                                     r->headers_in.accept_encoding->value.len);
-    }
-
-    if (r->headers_in.accept_language) {
-        len += ngx_http_v3_encode_header_lri(NULL, 0,
-                                     NGX_HTTP_V3_HEADER_ACCEPT_LANGUAGE, NULL,
-                                     r->headers_in.accept_language->value.len);
-    }
-
-    if (r->headers_in.user_agent) {
-        len += ngx_http_v3_encode_header_lri(NULL, 0,
-                                          NGX_HTTP_V3_HEADER_USER_AGENT, NULL,
-                                          r->headers_in.user_agent->value.len);
-    }
-
-    b = ngx_create_temp_buf(r->pool, len);
-    if (b == NULL) {
-        return NULL;
-    }
-
-    b->last = (u_char *) ngx_http_v3_encode_varlen_int(b->last, push_id);
-
-    b->last = (u_char *) ngx_http_v3_encode_header_block_prefix(b->last,
-                                                                0, 0, 0);
-
-    b->last = (u_char *) ngx_http_v3_encode_header_ri(b->last, 0,
-                                                NGX_HTTP_V3_HEADER_METHOD_GET);
-
-    b->last = (u_char *) ngx_http_v3_encode_header_lri(b->last, 0,
-                                                  NGX_HTTP_V3_HEADER_AUTHORITY,
-                                                  r->headers_in.server.data,
-                                                  r->headers_in.server.len);
-
-    if (path->len == 1 && path->data[0] == '/') {
-        b->last = (u_char *) ngx_http_v3_encode_header_ri(b->last, 0,
-                                                 NGX_HTTP_V3_HEADER_PATH_ROOT);
-
-    } else {
-        b->last = (u_char *) ngx_http_v3_encode_header_lri(b->last, 0,
-                                                  NGX_HTTP_V3_HEADER_PATH_ROOT,
-                                                  path->data, path->len);
-    }
-
-    if (r->schema.len == 5 && ngx_strncmp(r->schema.data, "https", 5) == 0) {
-        b->last = (u_char *) ngx_http_v3_encode_header_ri(b->last, 0,
-                                              NGX_HTTP_V3_HEADER_SCHEME_HTTPS);
-
-    } else if (r->schema.len == 4
-               && ngx_strncmp(r->schema.data, "http", 4) == 0)
-    {
-        b->last = (u_char *) ngx_http_v3_encode_header_ri(b->last, 0,
-                                               NGX_HTTP_V3_HEADER_SCHEME_HTTP);
-
-    } else {
-        b->last = (u_char *) ngx_http_v3_encode_header_lri(b->last, 0,
-                                                NGX_HTTP_V3_HEADER_SCHEME_HTTP,
-                                                r->schema.data, r->schema.len);
-    }
-
-    if (r->headers_in.accept_encoding) {
-        b->last = (u_char *) ngx_http_v3_encode_header_lri(b->last, 0,
-                                     NGX_HTTP_V3_HEADER_ACCEPT_ENCODING,
-                                     r->headers_in.accept_encoding->value.data,
-                                     r->headers_in.accept_encoding->value.len);
-    }
-
-    if (r->headers_in.accept_language) {
-        b->last = (u_char *) ngx_http_v3_encode_header_lri(b->last, 0,
-                                     NGX_HTTP_V3_HEADER_ACCEPT_LANGUAGE,
-                                     r->headers_in.accept_language->value.data,
-                                     r->headers_in.accept_language->value.len);
-    }
-
-    if (r->headers_in.user_agent) {
-        b->last = (u_char *) ngx_http_v3_encode_header_lri(b->last, 0,
-                                          NGX_HTTP_V3_HEADER_USER_AGENT,
-                                          r->headers_in.user_agent->value.data,
-                                          r->headers_in.user_agent->value.len);
-    }
-
-    cl = ngx_alloc_chain_link(r->pool);
-    if (cl == NULL) {
-        return NULL;
-    }
-
-    cl->buf = b;
-    cl->next = NULL;
-
-    n = b->last - b->pos;
-
-    len = ngx_http_v3_encode_varlen_int(NULL, NGX_HTTP_V3_FRAME_PUSH_PROMISE)
-          + ngx_http_v3_encode_varlen_int(NULL, n);
-
-    b = ngx_create_temp_buf(r->pool, len);
-    if (b == NULL) {
-        return NULL;
-    }
-
-    b->last = (u_char *) ngx_http_v3_encode_varlen_int(b->last,
-                                               NGX_HTTP_V3_FRAME_PUSH_PROMISE);
-    b->last = (u_char *) ngx_http_v3_encode_varlen_int(b->last, n);
-
-    hl = ngx_alloc_chain_link(r->pool);
-    if (hl == NULL) {
-        return NULL;
-    }
-
-    hl->buf = b;
-    hl->next = cl;
-
-    return hl;
-}