|  |  | 
|  | /* | 
|  | * Copyright (C) Igor Sysoev | 
|  | */ | 
|  |  | 
|  |  | 
|  | #include <ngx_config.h> | 
|  | #include <ngx_core.h> | 
|  | #include <ngx_http.h> | 
|  | #include <nginx.h> | 
|  |  | 
|  |  | 
|  | static u_char error_tail[] = | 
|  | "<hr><center>" NGINX_VER "</center>" CRLF | 
|  | "</body>" CRLF | 
|  | "</html>" CRLF | 
|  | ; | 
|  |  | 
|  |  | 
|  | static u_char ngx_http_msie_stub[] = | 
|  | "<!-- The padding to disable MSIE's friendly error page -->" CRLF | 
|  | "<!-- The padding to disable MSIE's friendly error page -->" CRLF | 
|  | "<!-- The padding to disable MSIE's friendly error page -->" CRLF | 
|  | "<!-- The padding to disable MSIE's friendly error page -->" CRLF | 
|  | "<!-- The padding to disable MSIE's friendly error page -->" CRLF | 
|  | "<!-- The padding to disable MSIE's friendly error page -->" CRLF | 
|  | ; | 
|  |  | 
|  |  | 
|  | static u_char ngx_http_msie_refresh_head[] = | 
|  | "<html><head><meta http-equiv=\"Refresh\" content=\"0; URL="; | 
|  |  | 
|  |  | 
|  | static u_char ngx_http_msie_refresh_tail[] = | 
|  | "\"></head><body></body></html>" CRLF; | 
|  |  | 
|  |  | 
|  | static char error_301_page[] = | 
|  | "<html>" CRLF | 
|  | "<head><title>301 Moved Permanently</title></head>" CRLF | 
|  | "<body bgcolor=\"white\">" CRLF | 
|  | "<center><h1>301 Moved Permanently</h1></center>" CRLF | 
|  | ; | 
|  |  | 
|  |  | 
|  | static char error_302_page[] = | 
|  | "<html>" CRLF | 
|  | "<head><title>302 Found</title></head>" CRLF | 
|  | "<body bgcolor=\"white\">" CRLF | 
|  | "<center><h1>302 Found</h1></center>" CRLF | 
|  | ; | 
|  |  | 
|  |  | 
|  | static char error_400_page[] = | 
|  | "<html>" CRLF | 
|  | "<head><title>400 Bad Request</title></head>" CRLF | 
|  | "<body bgcolor=\"white\">" CRLF | 
|  | "<center><h1>400 Bad Request</h1></center>" CRLF | 
|  | ; | 
|  |  | 
|  |  | 
|  | static char error_401_page[] = | 
|  | "<html>" CRLF | 
|  | "<head><title>401 Authorization Required</title></head>" CRLF | 
|  | "<body bgcolor=\"white\">" CRLF | 
|  | "<center><h1>401 Authorization Required</h1></center>" CRLF | 
|  | ; | 
|  |  | 
|  |  | 
|  | static char error_402_page[] = | 
|  | "<html>" CRLF | 
|  | "<head><title>402 Payment Required</title></head>" CRLF | 
|  | "<body bgcolor=\"white\">" CRLF | 
|  | "<center><h1>402 Payment Required</h1></center>" CRLF | 
|  | ; | 
|  |  | 
|  |  | 
|  | static char error_403_page[] = | 
|  | "<html>" CRLF | 
|  | "<head><title>403 Forbidden</title></head>" CRLF | 
|  | "<body bgcolor=\"white\">" CRLF | 
|  | "<center><h1>403 Forbidden</h1></center>" CRLF | 
|  | ; | 
|  |  | 
|  |  | 
|  | static char error_404_page[] = | 
|  | "<html>" CRLF | 
|  | "<head><title>404 Not Found</title></head>" CRLF | 
|  | "<body bgcolor=\"white\">" CRLF | 
|  | "<center><h1>404 Not Found</h1></center>" CRLF | 
|  | ; | 
|  |  | 
|  |  | 
|  | static char error_405_page[] = | 
|  | "<html>" CRLF | 
|  | "<head><title>405 Not Allowed</title></head>" CRLF | 
|  | "<body bgcolor=\"white\">" CRLF | 
|  | "<center><h1>405 Not Allowed</h1></center>" CRLF | 
|  | ; | 
|  |  | 
|  |  | 
|  | static char error_406_page[] = | 
|  | "<html>" CRLF | 
|  | "<head><title>406 Not Acceptable</title></head>" CRLF | 
|  | "<body bgcolor=\"white\">" CRLF | 
|  | "<center><h1>406 Not Acceptable</h1></center>" CRLF | 
|  | ; | 
|  |  | 
|  |  | 
|  | static char error_408_page[] = | 
|  | "<html>" CRLF | 
|  | "<head><title>408 Request Time-out</title></head>" CRLF | 
|  | "<body bgcolor=\"white\">" CRLF | 
|  | "<center><h1>408 Request Time-out</h1></center>" CRLF | 
|  | ; | 
|  |  | 
|  |  | 
|  | static char error_409_page[] = | 
|  | "<html>" CRLF | 
|  | "<head><title>409 Conflict</title></head>" CRLF | 
|  | "<body bgcolor=\"white\">" CRLF | 
|  | "<center><h1>409 Conflict</h1></center>" CRLF | 
|  | ; | 
|  |  | 
|  |  | 
|  | static char error_410_page[] = | 
|  | "<html>" CRLF | 
|  | "<head><title>410 Gone</title></head>" CRLF | 
|  | "<body bgcolor=\"white\">" CRLF | 
|  | "<center><h1>410 Gone</h1></center>" CRLF | 
|  | ; | 
|  |  | 
|  |  | 
|  | static char error_411_page[] = | 
|  | "<html>" CRLF | 
|  | "<head><title>411 Length Required</title></head>" CRLF | 
|  | "<body bgcolor=\"white\">" CRLF | 
|  | "<center><h1>411 Length Required</h1></center>" CRLF | 
|  | ; | 
|  |  | 
|  |  | 
|  | static char error_413_page[] = | 
|  | "<html>" CRLF | 
|  | "<head><title>413 Request Entity Too Large</title></head>" CRLF | 
|  | "<body bgcolor=\"white\">" CRLF | 
|  | "<center><h1>413 Request Entity Too Large</h1></center>" CRLF | 
|  | ; | 
|  |  | 
|  |  | 
|  | static char error_414_page[] = | 
|  | "<html>" CRLF | 
|  | "<head><title>414 Request-URI Too Large</title></head>" CRLF | 
|  | "<body bgcolor=\"white\">" CRLF | 
|  | "<center><h1>414 Request-URI Too Large</h1></center>" CRLF | 
|  | ; | 
|  |  | 
|  |  | 
|  | static char error_415_page[] = | 
|  | "<html>" CRLF | 
|  | "<head><title>415 Unsupported Media Type</title></head>" CRLF | 
|  | "<body bgcolor=\"white\">" CRLF | 
|  | "<center><h1>415 Unsupported Media Type</h1></center>" CRLF | 
|  | ; | 
|  |  | 
|  |  | 
|  | static char error_416_page[] = | 
|  | "<html>" CRLF | 
|  | "<head><title>416 Requested Range Not Satisfiable</title></head>" CRLF | 
|  | "<body bgcolor=\"white\">" CRLF | 
|  | "<center><h1>416 Requested Range Not Satisfiable</h1></center>" CRLF | 
|  | ; | 
|  |  | 
|  |  | 
|  | static char error_495_page[] = | 
|  | "<html>" CRLF | 
|  | "<head><title>400 The SSL certificate error</title></head>" | 
|  | CRLF | 
|  | "<body bgcolor=\"white\">" CRLF | 
|  | "<center><h1>400 Bad Request</h1></center>" CRLF | 
|  | "<center>The SSL certificate error</center>" CRLF | 
|  | ; | 
|  |  | 
|  |  | 
|  | static char error_496_page[] = | 
|  | "<html>" CRLF | 
|  | "<head><title>400 No required SSL certificate was sent</title></head>" | 
|  | CRLF | 
|  | "<body bgcolor=\"white\">" CRLF | 
|  | "<center><h1>400 Bad Request</h1></center>" CRLF | 
|  | "<center>No required SSL certificate was sent</center>" CRLF | 
|  | ; | 
|  |  | 
|  |  | 
|  | static char error_497_page[] = | 
|  | "<html>" CRLF | 
|  | "<head><title>400 The plain HTTP request was sent to HTTPS port</title></head>" | 
|  | CRLF | 
|  | "<body bgcolor=\"white\">" CRLF | 
|  | "<center><h1>400 Bad Request</h1></center>" CRLF | 
|  | "<center>The plain HTTP request was sent to HTTPS port</center>" CRLF | 
|  | ; | 
|  |  | 
|  |  | 
|  | static char error_500_page[] = | 
|  | "<html>" CRLF | 
|  | "<head><title>500 Internal Server Error</title></head>" CRLF | 
|  | "<body bgcolor=\"white\">" CRLF | 
|  | "<center><h1>500 Internal Server Error</h1></center>" CRLF | 
|  | ; | 
|  |  | 
|  |  | 
|  | static char error_501_page[] = | 
|  | "<html>" CRLF | 
|  | "<head><title>501 Method Not Implemented</title></head>" CRLF | 
|  | "<body bgcolor=\"white\">" CRLF | 
|  | "<center><h1>501 Method Not Implemented</h1></center>" CRLF | 
|  | ; | 
|  |  | 
|  |  | 
|  | static char error_502_page[] = | 
|  | "<html>" CRLF | 
|  | "<head><title>502 Bad Gateway</title></head>" CRLF | 
|  | "<body bgcolor=\"white\">" CRLF | 
|  | "<center><h1>502 Bad Gateway</h1></center>" CRLF | 
|  | ; | 
|  |  | 
|  |  | 
|  | static char error_503_page[] = | 
|  | "<html>" CRLF | 
|  | "<head><title>503 Service Temporarily Unavailable</title></head>" CRLF | 
|  | "<body bgcolor=\"white\">" CRLF | 
|  | "<center><h1>503 Service Temporarily Unavailable</h1></center>" CRLF | 
|  | ; | 
|  |  | 
|  |  | 
|  | static char error_504_page[] = | 
|  | "<html>" CRLF | 
|  | "<head><title>504 Gateway Time-out</title></head>" CRLF | 
|  | "<body bgcolor=\"white\">" CRLF | 
|  | "<center><h1>504 Gateway Time-out</h1></center>" CRLF | 
|  | ; | 
|  |  | 
|  |  | 
|  | static char error_507_page[] = | 
|  | "<html>" CRLF | 
|  | "<head><title>507 Insufficient Storage</title></head>" CRLF | 
|  | "<body bgcolor=\"white\">" CRLF | 
|  | "<center><h1>507 Insufficient Storage</h1></center>" CRLF | 
|  | ; | 
|  |  | 
|  |  | 
|  | static ngx_str_t error_pages[] = { | 
|  |  | 
|  | ngx_null_string,             /* 201, 204 */ | 
|  |  | 
|  | #define NGX_HTTP_LEVEL_200  1 | 
|  |  | 
|  | /* ngx_null_string, */       /* 300 */ | 
|  | ngx_string(error_301_page), | 
|  | ngx_string(error_302_page), | 
|  | ngx_null_string,             /* 303 */ | 
|  |  | 
|  | #define NGX_HTTP_LEVEL_300  3 | 
|  |  | 
|  | ngx_string(error_400_page), | 
|  | ngx_string(error_401_page), | 
|  | ngx_string(error_402_page), | 
|  | ngx_string(error_403_page), | 
|  | ngx_string(error_404_page), | 
|  | ngx_string(error_405_page), | 
|  | ngx_string(error_406_page), | 
|  | ngx_null_string,             /* 407 */ | 
|  | ngx_string(error_408_page), | 
|  | ngx_string(error_409_page), | 
|  | ngx_string(error_410_page), | 
|  | ngx_string(error_411_page), | 
|  | ngx_null_string,             /* 412 */ | 
|  | ngx_string(error_413_page), | 
|  | ngx_string(error_414_page), | 
|  | ngx_string(error_415_page), | 
|  | ngx_string(error_416_page), | 
|  |  | 
|  | #define NGX_HTTP_LEVEL_400  17 | 
|  |  | 
|  | ngx_string(error_495_page),  /* 495, https certificate error */ | 
|  | ngx_string(error_496_page),  /* 496, https no certificate */ | 
|  | ngx_string(error_497_page),  /* 497, http to https */ | 
|  | ngx_string(error_404_page),  /* 498, invalid host name */ | 
|  | ngx_null_string,             /* 499, client had closed connection */ | 
|  |  | 
|  | ngx_string(error_500_page), | 
|  | ngx_string(error_501_page), | 
|  | ngx_string(error_502_page), | 
|  | ngx_string(error_503_page), | 
|  | ngx_string(error_504_page), | 
|  | ngx_null_string,             /* 505 */ | 
|  | ngx_null_string,             /* 506 */ | 
|  | ngx_string(error_507_page) | 
|  | }; | 
|  |  | 
|  |  | 
|  | static ngx_str_t  ngx_http_get_name = { 3, (u_char *) "GET " }; | 
|  |  | 
|  |  | 
|  | ngx_int_t | 
|  | ngx_http_special_response_handler(ngx_http_request_t *r, ngx_int_t error) | 
|  | { | 
|  | u_char                    *p; | 
|  | size_t                     msie_refresh; | 
|  | ngx_int_t                  rc; | 
|  | ngx_buf_t                 *b; | 
|  | ngx_str_t                 *uri, *location; | 
|  | ngx_uint_t                 i, n, err, msie_padding; | 
|  | ngx_chain_t               *out, *cl; | 
|  | ngx_http_err_page_t       *err_page; | 
|  | ngx_http_core_loc_conf_t  *clcf; | 
|  |  | 
|  | ngx_log_debug2(NGX_LOG_DEBUG_HTTP, r->connection->log, 0, | 
|  | "http special response: %d, \"%V\"", error, &r->uri); | 
|  |  | 
|  | rc = ngx_http_discard_body(r); | 
|  |  | 
|  | if (rc == NGX_HTTP_INTERNAL_SERVER_ERROR) { | 
|  | error = NGX_HTTP_INTERNAL_SERVER_ERROR; | 
|  | } | 
|  |  | 
|  | r->err_status = error; | 
|  |  | 
|  | if (r->keepalive != 0) { | 
|  | switch (error) { | 
|  | case NGX_HTTP_BAD_REQUEST: | 
|  | case NGX_HTTP_REQUEST_ENTITY_TOO_LARGE: | 
|  | case NGX_HTTP_REQUEST_URI_TOO_LARGE: | 
|  | case NGX_HTTP_TO_HTTPS: | 
|  | case NGX_HTTPS_CERT_ERROR: | 
|  | case NGX_HTTPS_NO_CERT: | 
|  | case NGX_HTTP_INTERNAL_SERVER_ERROR: | 
|  | r->keepalive = 0; | 
|  | } | 
|  | } | 
|  |  | 
|  | if (r->lingering_close == 1) { | 
|  | switch (error) { | 
|  | case NGX_HTTP_BAD_REQUEST: | 
|  | case NGX_HTTP_TO_HTTPS: | 
|  | case NGX_HTTPS_CERT_ERROR: | 
|  | case NGX_HTTPS_NO_CERT: | 
|  | r->lingering_close = 0; | 
|  | } | 
|  | } | 
|  |  | 
|  | r->headers_out.content_type.len = 0; | 
|  |  | 
|  | clcf = ngx_http_get_module_loc_conf(r, ngx_http_core_module); | 
|  |  | 
|  | if (!r->error_page && clcf->error_pages) { | 
|  |  | 
|  | if (clcf->recursive_error_pages == 0) { | 
|  | r->error_page = 1; | 
|  | } | 
|  |  | 
|  | err_page = clcf->error_pages->elts; | 
|  |  | 
|  | for (i = 0; i < clcf->error_pages->nelts; i++) { | 
|  |  | 
|  | if (err_page[i].status == error) { | 
|  | r->err_status = err_page[i].overwrite; | 
|  |  | 
|  | r->method = NGX_HTTP_GET; | 
|  | r->method_name = ngx_http_get_name; | 
|  |  | 
|  | uri = &err_page[i].uri; | 
|  |  | 
|  | if (err_page[i].uri_lengths) { | 
|  | if (ngx_http_script_run(r, uri, | 
|  | err_page[i].uri_lengths->elts, 0, | 
|  | err_page[i].uri_values->elts) | 
|  | == NULL) | 
|  | { | 
|  | return NGX_ERROR; | 
|  | } | 
|  |  | 
|  | if (r->zero_in_uri) { | 
|  | for (n = 0; n < uri->len; n++) { | 
|  | if (uri->data[n] == '\0') { | 
|  | goto zero; | 
|  | } | 
|  | } | 
|  |  | 
|  | r->zero_in_uri = 0; | 
|  | } | 
|  |  | 
|  | } else { | 
|  | r->zero_in_uri = 0; | 
|  | } | 
|  |  | 
|  | zero: | 
|  |  | 
|  | if (uri->data[0] == '/') { | 
|  | return ngx_http_internal_redirect(r, uri, NULL); | 
|  | } | 
|  |  | 
|  | r->headers_out.location = | 
|  | ngx_list_push(&r->headers_out.headers); | 
|  |  | 
|  | if (r->headers_out.location) { | 
|  | error = NGX_HTTP_MOVED_TEMPORARILY; | 
|  |  | 
|  | r->err_status = NGX_HTTP_MOVED_TEMPORARILY; | 
|  |  | 
|  | r->headers_out.location->hash = 1; | 
|  | r->headers_out.location->key.len = sizeof("Location") - 1; | 
|  | r->headers_out.location->key.data = (u_char *) "Location"; | 
|  | r->headers_out.location->value = *uri; | 
|  |  | 
|  | } else { | 
|  | return NGX_ERROR; | 
|  | } | 
|  | } | 
|  | } | 
|  | } | 
|  |  | 
|  | if (error == NGX_HTTP_CREATED) { | 
|  | /* 201 */ | 
|  | err = 0; | 
|  | r->header_only = 1; | 
|  |  | 
|  | } else if (error == NGX_HTTP_NO_CONTENT) { | 
|  | /* 204 */ | 
|  | err = 0; | 
|  |  | 
|  | } else if (error < NGX_HTTP_BAD_REQUEST) { | 
|  | /* 3XX */ | 
|  | err = error - NGX_HTTP_MOVED_PERMANENTLY + NGX_HTTP_LEVEL_200; | 
|  |  | 
|  | } else if (error < NGX_HTTP_OWN_CODES) { | 
|  | /* 4XX */ | 
|  | err = error - NGX_HTTP_BAD_REQUEST + NGX_HTTP_LEVEL_200 | 
|  | + NGX_HTTP_LEVEL_300; | 
|  |  | 
|  | } else { | 
|  | /* 49X, 5XX */ | 
|  | err = error - NGX_HTTP_OWN_CODES + NGX_HTTP_LEVEL_200 | 
|  | + NGX_HTTP_LEVEL_300 | 
|  | + NGX_HTTP_LEVEL_400; | 
|  | switch (error) { | 
|  | case NGX_HTTP_TO_HTTPS: | 
|  | case NGX_HTTPS_CERT_ERROR: | 
|  | case NGX_HTTPS_NO_CERT: | 
|  | r->err_status = NGX_HTTP_BAD_REQUEST; | 
|  | error = NGX_HTTP_BAD_REQUEST; | 
|  | break; | 
|  | } | 
|  | } | 
|  |  | 
|  | msie_padding = 0; | 
|  |  | 
|  | if (!r->zero_body) { | 
|  | if (error_pages[err].len) { | 
|  | r->headers_out.content_length_n = error_pages[err].len | 
|  | + sizeof(error_tail) - 1; | 
|  |  | 
|  | if (clcf->msie_padding | 
|  | && r->headers_in.msie | 
|  | && r->http_version >= NGX_HTTP_VERSION_10 | 
|  | && error >= NGX_HTTP_BAD_REQUEST | 
|  | && error != NGX_HTTP_REQUEST_URI_TOO_LARGE) | 
|  | { | 
|  | r->headers_out.content_length_n += | 
|  | sizeof(ngx_http_msie_stub) - 1; | 
|  | msie_padding = 1; | 
|  | } | 
|  |  | 
|  | r->headers_out.content_type.len = sizeof("text/html") - 1; | 
|  | r->headers_out.content_type.data = (u_char *) "text/html"; | 
|  |  | 
|  | } else { | 
|  | r->headers_out.content_length_n = -1; | 
|  | } | 
|  |  | 
|  | } else { | 
|  | r->headers_out.content_length_n = 0; | 
|  | err = 0; | 
|  | } | 
|  |  | 
|  | if (r->headers_out.content_length) { | 
|  | r->headers_out.content_length->hash = 0; | 
|  | r->headers_out.content_length = NULL; | 
|  | } | 
|  |  | 
|  | msie_refresh = 0; | 
|  | location = NULL; | 
|  |  | 
|  | if (clcf->msie_refresh | 
|  | && r->headers_in.msie | 
|  | && (error == NGX_HTTP_MOVED_PERMANENTLY | 
|  | || error == NGX_HTTP_MOVED_TEMPORARILY)) | 
|  | { | 
|  | location = &r->headers_out.location->value; | 
|  | msie_refresh = sizeof(ngx_http_msie_refresh_head) - 1 | 
|  | + location->len | 
|  | + sizeof(ngx_http_msie_refresh_tail) - 1; | 
|  |  | 
|  | r->err_status = NGX_HTTP_OK; | 
|  | r->headers_out.content_type_len = sizeof("text/html") - 1; | 
|  | r->headers_out.content_length_n = msie_refresh; | 
|  | r->headers_out.location->hash = 0; | 
|  | r->headers_out.location = NULL; | 
|  | } | 
|  |  | 
|  | ngx_http_clear_accept_ranges(r); | 
|  | ngx_http_clear_last_modified(r); | 
|  |  | 
|  | rc = ngx_http_send_header(r); | 
|  |  | 
|  | if (rc == NGX_ERROR || r->header_only) { | 
|  | return rc; | 
|  | } | 
|  |  | 
|  |  | 
|  | if (msie_refresh == 0) { | 
|  |  | 
|  | if (error_pages[err].len == 0) { | 
|  | return NGX_OK; | 
|  | } | 
|  |  | 
|  | b = ngx_calloc_buf(r->pool); | 
|  | if (b == NULL) { | 
|  | return NGX_ERROR; | 
|  | } | 
|  |  | 
|  | b->memory = 1; | 
|  | b->pos = error_pages[err].data; | 
|  | b->last = error_pages[err].data + error_pages[err].len; | 
|  |  | 
|  | cl = ngx_alloc_chain_link(r->pool); | 
|  | if (cl == NULL) { | 
|  | return NGX_ERROR; | 
|  | } | 
|  |  | 
|  | cl->buf = b; | 
|  | out = cl; | 
|  |  | 
|  |  | 
|  | b = ngx_calloc_buf(r->pool); | 
|  | if (b == NULL) { | 
|  | return NGX_ERROR; | 
|  | } | 
|  |  | 
|  | b->memory = 1; | 
|  | b->pos = error_tail; | 
|  | b->last = error_tail + sizeof(error_tail) - 1; | 
|  |  | 
|  | cl->next = ngx_alloc_chain_link(r->pool); | 
|  | if (cl->next == NULL) { | 
|  | return NGX_ERROR; | 
|  | } | 
|  |  | 
|  | cl = cl->next; | 
|  | cl->buf = b; | 
|  |  | 
|  | if (msie_padding) { | 
|  | b = ngx_calloc_buf(r->pool); | 
|  | if (b == NULL) { | 
|  | return NGX_ERROR; | 
|  | } | 
|  |  | 
|  | b->memory = 1; | 
|  | b->pos = ngx_http_msie_stub; | 
|  | b->last = ngx_http_msie_stub + sizeof(ngx_http_msie_stub) - 1; | 
|  |  | 
|  | cl->next = ngx_alloc_chain_link(r->pool); | 
|  | if (cl->next == NULL) { | 
|  | return NGX_ERROR; | 
|  | } | 
|  |  | 
|  | cl = cl->next; | 
|  | cl->buf = b; | 
|  | } | 
|  |  | 
|  | } else { | 
|  | b = ngx_create_temp_buf(r->pool, msie_refresh); | 
|  | if (b == NULL) { | 
|  | return NGX_ERROR; | 
|  | } | 
|  |  | 
|  | p = ngx_cpymem(b->pos, ngx_http_msie_refresh_head, | 
|  | sizeof(ngx_http_msie_refresh_head) - 1); | 
|  |  | 
|  | p = ngx_cpymem(p, location->data, location->len); | 
|  |  | 
|  | b->last = ngx_cpymem(p, ngx_http_msie_refresh_tail, | 
|  | sizeof(ngx_http_msie_refresh_tail) - 1); | 
|  |  | 
|  | cl = ngx_alloc_chain_link(r->pool); | 
|  | if (cl == NULL) { | 
|  | return NGX_ERROR; | 
|  | } | 
|  |  | 
|  | cl->buf = b; | 
|  | out = cl; | 
|  | } | 
|  |  | 
|  | if (r == r->main) { | 
|  | b->last_buf = 1; | 
|  | } | 
|  |  | 
|  | b->last_in_chain = 1; | 
|  |  | 
|  | cl->next = NULL; | 
|  |  | 
|  | return ngx_http_output_filter(r, out); | 
|  | } |