Mercurial > hg > nginx-quic
view src/http/modules/ngx_http_empty_gif_module.c @ 4487:a786c85e8268
Disable symlinks: don't allow creating or truncating a file via a symlink in
the last path component if "if_not_owner" parameter is used.
To prevent race condition we have to open a file before checking its owner and
there's no way to change access flags for already opened file descriptor, so
we disable symlinks for the last path component at all if flags allow creating
or truncating the file.
| author | Valentin Bartenev <vbart@nginx.com> |
|---|---|
| date | Tue, 21 Feb 2012 15:04:41 +0000 |
| parents | d620f497c50f |
| children |
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/* * Copyright (C) Igor Sysoev * Copyright (C) Nginx, Inc. */ #include <ngx_config.h> #include <ngx_core.h> #include <ngx_http.h> static char *ngx_http_empty_gif(ngx_conf_t *cf, ngx_command_t *cmd, void *conf); static ngx_command_t ngx_http_empty_gif_commands[] = { { ngx_string("empty_gif"), NGX_HTTP_LOC_CONF|NGX_CONF_NOARGS, ngx_http_empty_gif, 0, 0, NULL }, ngx_null_command }; /* the minimal single pixel transparent GIF, 43 bytes */ static u_char ngx_empty_gif[] = { 'G', 'I', 'F', '8', '9', 'a', /* header */ /* logical screen descriptor */ 0x01, 0x00, /* logical screen width */ 0x01, 0x00, /* logical screen height */ 0x80, /* global 1-bit color table */ 0x01, /* background color #1 */ 0x00, /* no aspect ratio */ /* global color table */ 0x00, 0x00, 0x00, /* #0: black */ 0xff, 0xff, 0xff, /* #1: white */ /* graphic control extension */ 0x21, /* extension introducer */ 0xf9, /* graphic control label */ 0x04, /* block size */ 0x01, /* transparent color is given, */ /* no disposal specified, */ /* user input is not expected */ 0x00, 0x00, /* delay time */ 0x01, /* transparent color #1 */ 0x00, /* block terminator */ /* image descriptor */ 0x2c, /* image separator */ 0x00, 0x00, /* image left position */ 0x00, 0x00, /* image top position */ 0x01, 0x00, /* image width */ 0x01, 0x00, /* image height */ 0x00, /* no local color table, no interlaced */ /* table based image data */ 0x02, /* LZW minimum code size, */ /* must be at least 2-bit */ 0x02, /* block size */ 0x4c, 0x01, /* compressed bytes 01_001_100, 0000000_1 */ /* 100: clear code */ /* 001: 1 */ /* 101: end of information code */ 0x00, /* block terminator */ 0x3B /* trailer */ }; static ngx_http_module_t ngx_http_empty_gif_module_ctx = { NULL, /* preconfiguration */ NULL, /* 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_empty_gif_module = { NGX_MODULE_V1, &ngx_http_empty_gif_module_ctx, /* module context */ ngx_http_empty_gif_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_str_t ngx_http_gif_type = ngx_string("image/gif"); static ngx_int_t ngx_http_empty_gif_handler(ngx_http_request_t *r) { ngx_http_complex_value_t cv; if (!(r->method & (NGX_HTTP_GET|NGX_HTTP_HEAD))) { return NGX_HTTP_NOT_ALLOWED; } ngx_memzero(&cv, sizeof(ngx_http_complex_value_t)); cv.value.len = sizeof(ngx_empty_gif); cv.value.data = ngx_empty_gif; r->headers_out.last_modified_time = 23349600; return ngx_http_send_response(r, NGX_HTTP_OK, &ngx_http_gif_type, &cv); } static char * ngx_http_empty_gif(ngx_conf_t *cf, ngx_command_t *cmd, void *conf) { ngx_http_core_loc_conf_t *clcf; clcf = ngx_http_conf_get_module_loc_conf(cf, ngx_http_core_module); clcf->handler = ngx_http_empty_gif_handler; return NGX_CONF_OK; }