view src/http/ngx_http_cache.h @ 7354:1812f1d79d84

Fixed socket leak with "return 444" in error_page (ticket #274). Socket leak was observed in the following configuration: error_page 400 = /close; location = /close { return 444; } The problem is that "return 444" triggers termination of the request, and due to error_page termination thinks that it needs to use a posted request to clear stack. But at the early request processing where 400 errors are generated there are no ngx_http_run_posted_requests() calls, so the request is only terminated after an external event. Variants of the problem include "error_page 497" instead (ticket #695) and various other errors generated during early request processing (405, 414, 421, 494, 495, 496, 501, 505). The same problem can be also triggered with "return 499" and "return 408" as both codes trigger ngx_http_terminate_request(), much like "return 444". To fix this, the patch adds ngx_http_run_posted_requests() calls to ngx_http_process_request_line() and ngx_http_process_request_headers() functions, and to ngx_http_v2_run_request() and ngx_http_v2_push_stream() functions in HTTP/2. Since the ngx_http_process_request() function is now only called via other functions which call ngx_http_run_posted_requests(), the call there is no longer needed and was removed.
author Maxim Dounin <mdounin@mdounin.ru>
date Fri, 21 Sep 2018 15:59:30 +0300
parents 609daeb3b48b
children ccb5ff87ab3e
line wrap: on
line source


/*
 * Copyright (C) Igor Sysoev
 * Copyright (C) Nginx, Inc.
 */


#ifndef _NGX_HTTP_CACHE_H_INCLUDED_
#define _NGX_HTTP_CACHE_H_INCLUDED_


#include <ngx_config.h>
#include <ngx_core.h>
#include <ngx_http.h>


#define NGX_HTTP_CACHE_MISS          1
#define NGX_HTTP_CACHE_BYPASS        2
#define NGX_HTTP_CACHE_EXPIRED       3
#define NGX_HTTP_CACHE_STALE         4
#define NGX_HTTP_CACHE_UPDATING      5
#define NGX_HTTP_CACHE_REVALIDATED   6
#define NGX_HTTP_CACHE_HIT           7
#define NGX_HTTP_CACHE_SCARCE        8

#define NGX_HTTP_CACHE_KEY_LEN       16
#define NGX_HTTP_CACHE_ETAG_LEN      128
#define NGX_HTTP_CACHE_VARY_LEN      128

#define NGX_HTTP_CACHE_VERSION       5


typedef struct {
    ngx_uint_t                       status;
    time_t                           valid;
} ngx_http_cache_valid_t;


typedef struct {
    ngx_rbtree_node_t                node;
    ngx_queue_t                      queue;

    u_char                           key[NGX_HTTP_CACHE_KEY_LEN
                                         - sizeof(ngx_rbtree_key_t)];

    unsigned                         count:20;
    unsigned                         uses:10;
    unsigned                         valid_msec:10;
    unsigned                         error:10;
    unsigned                         exists:1;
    unsigned                         updating:1;
    unsigned                         deleting:1;
    unsigned                         purged:1;
                                     /* 10 unused bits */

    ngx_file_uniq_t                  uniq;
    time_t                           expire;
    time_t                           valid_sec;
    size_t                           body_start;
    off_t                            fs_size;
    ngx_msec_t                       lock_time;
} ngx_http_file_cache_node_t;


struct ngx_http_cache_s {
    ngx_file_t                       file;
    ngx_array_t                      keys;
    uint32_t                         crc32;
    u_char                           key[NGX_HTTP_CACHE_KEY_LEN];
    u_char                           main[NGX_HTTP_CACHE_KEY_LEN];

    ngx_file_uniq_t                  uniq;
    time_t                           valid_sec;
    time_t                           updating_sec;
    time_t                           error_sec;
    time_t                           last_modified;
    time_t                           date;

    ngx_str_t                        etag;
    ngx_str_t                        vary;
    u_char                           variant[NGX_HTTP_CACHE_KEY_LEN];

    size_t                           header_start;
    size_t                           body_start;
    off_t                            length;
    off_t                            fs_size;

    ngx_uint_t                       min_uses;
    ngx_uint_t                       error;
    ngx_uint_t                       valid_msec;
    ngx_uint_t                       vary_tag;

    ngx_buf_t                       *buf;

    ngx_http_file_cache_t           *file_cache;
    ngx_http_file_cache_node_t      *node;

#if (NGX_THREADS || NGX_COMPAT)
    ngx_thread_task_t               *thread_task;
#endif

    ngx_msec_t                       lock_timeout;
    ngx_msec_t                       lock_age;
    ngx_msec_t                       lock_time;
    ngx_msec_t                       wait_time;

    ngx_event_t                      wait_event;

    unsigned                         lock:1;
    unsigned                         waiting:1;

    unsigned                         updated:1;
    unsigned                         updating:1;
    unsigned                         exists:1;
    unsigned                         temp_file:1;
    unsigned                         purged:1;
    unsigned                         reading:1;
    unsigned                         secondary:1;
    unsigned                         background:1;

    unsigned                         stale_updating:1;
    unsigned                         stale_error:1;
};


typedef struct {
    ngx_uint_t                       version;
    time_t                           valid_sec;
    time_t                           updating_sec;
    time_t                           error_sec;
    time_t                           last_modified;
    time_t                           date;
    uint32_t                         crc32;
    u_short                          valid_msec;
    u_short                          header_start;
    u_short                          body_start;
    u_char                           etag_len;
    u_char                           etag[NGX_HTTP_CACHE_ETAG_LEN];
    u_char                           vary_len;
    u_char                           vary[NGX_HTTP_CACHE_VARY_LEN];
    u_char                           variant[NGX_HTTP_CACHE_KEY_LEN];
} ngx_http_file_cache_header_t;


typedef struct {
    ngx_rbtree_t                     rbtree;
    ngx_rbtree_node_t                sentinel;
    ngx_queue_t                      queue;
    ngx_atomic_t                     cold;
    ngx_atomic_t                     loading;
    off_t                            size;
    ngx_uint_t                       count;
    ngx_uint_t                       watermark;
} ngx_http_file_cache_sh_t;


struct ngx_http_file_cache_s {
    ngx_http_file_cache_sh_t        *sh;
    ngx_slab_pool_t                 *shpool;

    ngx_path_t                      *path;

    off_t                            max_size;
    size_t                           bsize;

    time_t                           inactive;

    time_t                           fail_time;

    ngx_uint_t                       files;
    ngx_uint_t                       loader_files;
    ngx_msec_t                       last;
    ngx_msec_t                       loader_sleep;
    ngx_msec_t                       loader_threshold;

    ngx_uint_t                       manager_files;
    ngx_msec_t                       manager_sleep;
    ngx_msec_t                       manager_threshold;

    ngx_shm_zone_t                  *shm_zone;

    ngx_uint_t                       use_temp_path;
                                     /* unsigned use_temp_path:1 */
};


ngx_int_t ngx_http_file_cache_new(ngx_http_request_t *r);
ngx_int_t ngx_http_file_cache_create(ngx_http_request_t *r);
void ngx_http_file_cache_create_key(ngx_http_request_t *r);
ngx_int_t ngx_http_file_cache_open(ngx_http_request_t *r);
ngx_int_t ngx_http_file_cache_set_header(ngx_http_request_t *r, u_char *buf);
void ngx_http_file_cache_update(ngx_http_request_t *r, ngx_temp_file_t *tf);
void ngx_http_file_cache_update_header(ngx_http_request_t *r);
ngx_int_t ngx_http_cache_send(ngx_http_request_t *);
void ngx_http_file_cache_free(ngx_http_cache_t *c, ngx_temp_file_t *tf);
time_t ngx_http_file_cache_valid(ngx_array_t *cache_valid, ngx_uint_t status);

char *ngx_http_file_cache_set_slot(ngx_conf_t *cf, ngx_command_t *cmd,
    void *conf);
char *ngx_http_file_cache_valid_set_slot(ngx_conf_t *cf, ngx_command_t *cmd,
    void *conf);


extern ngx_str_t  ngx_http_cache_status[];


#endif /* _NGX_HTTP_CACHE_H_INCLUDED_ */