ngx_http_browser_module.c

nginx 反向代理0.7.1版本 用于实现反向代理

/*
 * Copyright (C) Igor Sysoev
 */


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


/*
 * The module can check browser versions conforming to the following formats:
 * X, X.X, X.X.X, and X.X.X.X.  The maximum values of each format may be
 * 4000, 4000.99, 4000.99.99, and 4000.99.99.99.
 */


#define  NGX_HTTP_MODERN_BROWSER   0
#define  NGX_HTTP_ANCIENT_BROWSER  1


typedef struct {
    u_char                      browser[12];
    size_t                      skip;
    size_t                      add;
    u_char                      name[12];
} ngx_http_modern_browser_mask_t;


typedef struct {
    ngx_uint_t                  version;
    size_t                      skip;
    size_t                      add;
    u_char                      name[12];
} ngx_http_modern_browser_t;


typedef struct {
    ngx_str_t                   name;
    ngx_http_get_variable_pt    handler;
    uintptr_t                   data;
} ngx_http_browser_variable_t;


typedef struct {
    ngx_array_t                *modern_browsers;
    ngx_array_t                *ancient_browsers;
    ngx_http_variable_value_t  *modern_browser_value;
    ngx_http_variable_value_t  *ancient_browser_value;

    unsigned                    modern_unlisted_browsers:1;
    unsigned                    netscape4:1;
} ngx_http_browser_conf_t;


static ngx_int_t ngx_http_msie_variable(ngx_http_request_t *r,
    ngx_http_variable_value_t *v, uintptr_t data);
static ngx_int_t ngx_http_browser_variable(ngx_http_request_t *r,
    ngx_http_variable_value_t *v, uintptr_t data);

static ngx_uint_t ngx_http_browser(ngx_http_request_t *r,
    ngx_http_browser_conf_t *cf);

static ngx_int_t ngx_http_browser_add_variable(ngx_conf_t *cf);
static void *ngx_http_browser_create_conf(ngx_conf_t *cf);
static char *ngx_http_browser_merge_conf(ngx_conf_t *cf, void *parent,
    void *child);
static int ngx_libc_cdecl ngx_http_modern_browser_sort(const void *one,
    const void *two);
static char *ngx_http_modern_browser(ngx_conf_t *cf, ngx_command_t *cmd,
    void *conf);
static char *ngx_http_ancient_browser(ngx_conf_t *cf, ngx_command_t *cmd,
    void *conf);
static char *ngx_http_modern_browser_value(ngx_conf_t *cf, ngx_command_t *cmd,
    void *conf);
static char *ngx_http_ancient_browser_value(ngx_conf_t *cf, ngx_command_t *cmd,
    void *conf);


static ngx_command_t  ngx_http_browser_commands[] = {

    { ngx_string("modern_browser"),
      NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_TAKE12,
      ngx_http_modern_browser,
      NGX_HTTP_LOC_CONF_OFFSET,
      0,
      NULL },

    { ngx_string("ancient_browser"),
      NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_1MORE,
      ngx_http_ancient_browser,
      NGX_HTTP_LOC_CONF_OFFSET,
      0,
      NULL },

    { ngx_string("modern_browser_value"),
      NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_TAKE1,
      ngx_http_modern_browser_value,
      NGX_HTTP_LOC_CONF_OFFSET,
      0,
      NULL },

    { ngx_string("ancient_browser_value"),
      NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_TAKE1,
      ngx_http_ancient_browser_value,
      NGX_HTTP_LOC_CONF_OFFSET,
      0,
      NULL },

      ngx_null_command
};


static ngx_http_module_t  ngx_http_browser_module_ctx = {
    ngx_http_browser_add_variable,         /* preconfiguration */
    NULL,                                  /* postconfiguration */

    NULL,                                  /* create main configuration */
    NULL,                                  /* init main configuration */

    NULL,                                  /* create server configuration */
    NULL,                                  /* merge server configuration */

    ngx_http_browser_create_conf,          /* create location configuration */
    ngx_http_browser_merge_conf            /* merge location configuration */
};


ngx_module_t  ngx_http_browser_module = {
    NGX_MODULE_V1,
    &ngx_http_browser_module_ctx,          /* module context */
    ngx_http_browser_commands,             /* 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_modern_browser_mask_t  ngx_http_modern_browser_masks[] = {

    /* Opera must be the first browser to check */

    /*
     * "Opera/7.50 (X11; FreeBSD i386; U)  [en]"
     * "Mozilla/5.0 (X11; FreeBSD i386; U) Opera 7.50  [en]"
     * "Mozilla/4.0 (compatible; MSIE 6.0; X11; FreeBSD i386) Opera 7.50  [en]"
     * "Opera/8.0 (Windows NT 5.1; U; ru)"
     * "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.0; en) Opera 8.0"
     * "Opera/9.01 (X11; FreeBSD 6 i386; U; en)"
     */

    { "opera",
      0,
      sizeof("Opera ") - 1,
      "Opera"},

    /* "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1)" */

    { "msie",
      sizeof("Mozilla/4.0 (compatible; ") - 1,
      sizeof("MSIE ") - 1,
      "MSIE "},

    /*
     * "Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.0.0) Gecko/20020610"
     * "Mozilla/5.0 (Windows; U; Windows NT 5.1; ru-RU; rv:1.5) Gecko/20031006"
     * "Mozilla/5.0 (Windows; U; Windows NT 5.1; ru-RU; rv:1.6) Gecko/20040206
     *              Firefox/0.8"
     * "Mozilla/5.0 (Windows; U; Windows NT 5.1; ru-RU; rv:1.7.8)
     *              Gecko/20050511 Firefox/1.0.4"
     * "Mozilla/5.0 (X11; U; FreeBSD i386; en-US; rv:1.8.0.5) Gecko/20060729
     *              Firefox/1.5.0.5"
     */

    { "gecko",
      sizeof("Mozilla/5.0 (") - 1,
      sizeof("rv:") - 1,
      "rv:"},

    /*
     * "Mozilla/5.0 (Macintosh; U; PPC Mac OS X; ru-ru) AppleWebKit/125.2
     *              (KHTML, like Gecko) Safari/125.7"
     * "Mozilla/5.0 (SymbianOS/9.1; U; en-us) AppleWebKit/413
     *              (KHTML, like Gecko) Safari/413"
     * "Mozilla/5.0 (Macintosh; U; PPC Mac OS X; en) AppleWebKit/418
     *              (KHTML, like Gecko) Safari/417.9.3"
     * "Mozilla/5.0 (Macintosh; U; PPC Mac OS X; ru-ru) AppleWebKit/418.8
     *              (KHTML, like Gecko) Safari/419.3"
     */

    { "safari",
      sizeof("Mozilla/5.0 (") - 1,
      sizeof("Safari/") - 1,
      "Safari/"},

    /*
     * "Mozilla/5.0 (compatible; Konqueror/3.1; Linux)"
     * "Mozilla/5.0 (compatible; Konqueror/3.4; Linux) KHTML/3.4.2 (like Gecko)"
     * "Mozilla/5.0 (compatible; Konqueror/3.5; FreeBSD) KHTML/3.5.1
     *              (like Gecko)"
     */

    { "konqueror",
      sizeof("Mozilla/5.0 (compatible; ") - 1,
      sizeof("Konqueror/") - 1,
      "Konqueror/"},

    { "", 0, 0, "" }

};


static ngx_http_browser_variable_t  ngx_http_browsers[] = {
    { ngx_string("msie"), ngx_http_msie_variable, 0 },
    { ngx_string("modern_browser"), ngx_http_browser_variable,
          NGX_HTTP_MODERN_BROWSER },
    { ngx_string("ancient_browser"), ngx_http_browser_variable,
          NGX_HTTP_ANCIENT_BROWSER },
    { ngx_null_string, NULL, 0 }
};


static ngx_int_t
ngx_http_browser_variable(ngx_http_request_t *r, ngx_http_variable_value_t *v,
    uintptr_t data)
{
    ngx_uint_t                rc;
    ngx_http_browser_conf_t  *cf;

    cf = ngx_http_get_module_loc_conf(r, ngx_http_browser_module);

    rc = ngx_http_browser(r, cf);

    if (data == NGX_HTTP_MODERN_BROWSER && rc == NGX_HTTP_MODERN_BROWSER) {
        *v = *cf->modern_browser_value;
        return NGX_OK;
    }

    if (data == NGX_HTTP_ANCIENT_BROWSER && rc == NGX_HTTP_ANCIENT_BROWSER) {
        *v = *cf->ancient_browser_value;
        return NGX_OK;
    }

    *v = ngx_http_variable_null_value;
    return NGX_OK;
}


static ngx_uint_t
ngx_http_browser(ngx_http_request_t *r, ngx_http_browser_conf_t *cf)
{
    size_t                      len;
    u_char                     *name, *ua, *last, c;
    ngx_str_t                  *ancient;
    ngx_uint_t                  i, version, ver, scale;
    ngx_http_modern_browser_t  *modern;

    if (r->headers_in.user_agent == NULL) {
        if (cf->modern_unlisted_browsers) {
            return NGX_HTTP_MODERN_BROWSER;
        }

        return NGX_HTTP_ANCIENT_BROWSER;
    }

    ua = r->headers_in.user_agent->value.data;
    len = r->headers_in.user_agent->value.len;
    last = ua + len;

    if (cf->modern_browsers) {
        modern = cf->modern_browsers->elts;

        for (i = 0; i < cf->modern_browsers->nelts; i++) {
            name = ua + modern[i].skip;

            if (name >= last) {
                continue;
            }

            name = (u_char *) ngx_strstr(name, modern[i].name);

            if (name == NULL) {
                continue;
            }

            ngx_log_debug1(NGX_LOG_DEBUG_HTTP, r->connection->log, 0,
                           "browser: \"%s\"", name);

            name += modern[i].add;

            if (name >= last) {
                continue;
            }

            ngx_log_debug2(NGX_LOG_DEBUG_HTTP, r->connection->log, 0,
                           "version: \"%ui\" \"%s\"", modern[i].version, name);

            version = 0;
            ver = 0;
            scale = 1000000;

            while (name < last) {

                c = *name++;

                if (c >= '0' && c <= '9') {
                    ver = ver * 10 + (c - '0');
                    continue;
                }

                if (c == '.') {
                    version += ver * scale;

                    if (version > modern[i].version) {
                        return NGX_HTTP_MODERN_BROWSER;
                    }

                    ver = 0;
                    scale /= 100;
                    continue;
                }

                break;
            }

            version += ver * scale;

            ngx_log_debug2(NGX_LOG_DEBUG_HTTP, r->connection->log, 0,
                           "version: \"%ui\" \"%ui\"",
                           modern[i].version, version);

            if (version >= modern[i].version) {
                return NGX_HTTP_MODERN_BROWSER;
            }
        }

        if (!cf->modern_unlisted_browsers) {
            return NGX_HTTP_ANCIENT_BROWSER;
        }
    }

    if (cf->netscape4) {
        if (len > sizeof("Mozilla/4.72 ") - 1
            && ngx_strncmp(ua, "Mozilla/", sizeof("Mozilla/") - 1) == 0
            && ua[8] > '0' && ua[8] < '5')
        {
            return NGX_HTTP_ANCIENT_BROWSER;