From 2d9d99e1a64367b79a7e4bd1875098b6114f43c8 Mon Sep 17 00:00:00 2001
From: Baoshuo <i@baoshuo.ren>
Date: Wed, 12 Oct 2022 21:10:07 +0800
Subject: [PATCH] feat(web/image_hosting): get_image

---
 .../controllers/image_hosting/get_image.php    | 18 ++++++++++++++++++
 web/app/libs/uoj-rand-lib.php                  |  8 ++++----
 web/app/libs/uoj-validate-lib.php              |  4 ++++
 web/app/route.php                              |  2 +-
 4 files changed, 27 insertions(+), 5 deletions(-)

diff --git a/web/app/controllers/image_hosting/get_image.php b/web/app/controllers/image_hosting/get_image.php
index e6e8fae..1f53f04 100644
--- a/web/app/controllers/image_hosting/get_image.php
+++ b/web/app/controllers/image_hosting/get_image.php
@@ -4,3 +4,21 @@
 	if (!Auth::check() && UOJConfig::$data['switch']['force-login']) {
 		redirectToLogin();
 	}
+
+	$name = $_GET['image_name'];
+	if (!validateString($name)) {
+		become404Page();
+	}
+
+	$file_name = UOJContext::storagePath()."/image_hosting/$name.png";
+
+	$finfo = finfo_open(FILEINFO_MIME);
+	$mimetype = finfo_file($finfo, $file_name);
+	if ($mimetype === false) {
+		become404Page();
+	}
+	finfo_close($finfo);
+	
+	header("X-Sendfile: $file_name");
+	header("Content-type: $mimetype");
+	header("Cache-Control: max-age=604800", true);
diff --git a/web/app/libs/uoj-rand-lib.php b/web/app/libs/uoj-rand-lib.php
index d39c527..5c40015 100644
--- a/web/app/libs/uoj-rand-lib.php
+++ b/web/app/libs/uoj-rand-lib.php
@@ -4,7 +4,7 @@ function uojRand($l, $r) {
 	return mt_rand($l, $r);
 }
 
-function uojRandString($len, $charset = '0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ') {
+function uojRandString($len, $charset = '0123456789abcdefghijklmnopqrstuvwxyz') {
 	$n_chars = strlen($charset);
 	$str = '';
 	for ($i = 0; $i < $len; $i++) {
@@ -13,10 +13,10 @@ function uojRandString($len, $charset = '0123456789abcdefghijklmnopqrstuvwxyzABC
 	return $str;
 }
 
-function uojRandAvaiableFileName($dir) {
+function uojRandAvaiableFileName($dir, $length = 20, $suffix = '') {
 	do {
-		$fileName = $dir . uojRandString(20);
-	} while (file_exists(UOJContext::storagePath().$fileName));
+		$fileName = $dir . uojRandString($length);
+	} while (file_exists(UOJContext::storagePath().$fileName.$suffix));
 	return $fileName;
 }
 
diff --git a/web/app/libs/uoj-validate-lib.php b/web/app/libs/uoj-validate-lib.php
index eb991a5..a685868 100644
--- a/web/app/libs/uoj-validate-lib.php
+++ b/web/app/libs/uoj-validate-lib.php
@@ -51,3 +51,7 @@ function validateIP($ip) {
 function validateURL($url) {
 	return filter_var($url, FILTER_VALIDATE_URL) !== false;
 }
+
+function validateString($str) {
+	return preg_match('/[^0-9a-zA-Z]/', $str) !== true;
+}
diff --git a/web/app/route.php b/web/app/route.php
index 3b89394..753207d 100644
--- a/web/app/route.php
+++ b/web/app/route.php
@@ -5,7 +5,7 @@ Route::pattern('id', '[1-9][0-9]{0,9}');
 Route::pattern('contest_id', '[1-9][0-9]{0,9}');
 Route::pattern('tab', '\S{1,20}');
 Route::pattern('rand_str_id', '[0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ]{20}');
-Route::pattern('image_name', '[0123456789abcdefghijklmnopqrstuvwxyz]{7}');
+Route::pattern('image_name', '[0-9a-z]{1,20}');
 Route::pattern('upgrade_name', '[a-zA-Z0-9_]{1,50}');
 
 Route::group([