PPTP-VPN第三章——用户流量与并发数限制

在前面两篇文章中详细介绍了pptp vpn的安装与使用，以及如何配置用户认证存入mysql数据库。本文将在前面两篇文章的基础上介绍如何对用户的流量做限制，同时限制相同账号的用户，同一时刻的在线数为1。

前文传送门地址：

PPTP-VPN部署与简单使用 http://ylw6006.blog.51cto.com/470441/1794577

PPTP-VPN使用mysql进行用户登录认证 http://ylw6006.blog.51cto.com/470441/1795201

一、向mysql库表中插入基础数据

mysql> use radius

mysql> INSERT INTO radgroupreply (groupname,attribute,op,VALUE) VALUES ('user','Auth-Type',':=','Local');

mysql> INSERT INTO radgroupreply (groupname,attribute,op,VALUE) VALUES ('user','Service-Type',':=','Framed-User');

mysql> INSERT INTO radgroupreply (groupname,attribute,op,VALUE) VALUES ('user','Framed-IP-Address',':=','255.255.255.255');

mysql> INSERT INTO radgroupreply (groupname,attribute,op,VALUE) VALUES ('user','Framed-IP-Netmask',':=','255.255.255.0');

mysql> INSERT INTO radgroupreply (groupname,attribute,op,VALUE) VALUES ('user','Acct-Interim-Interval',':=','600');

mysql> INSERT INTO radgroupreply (groupname,attribute,op,VALUE) VALUES ('user','Max-Monthly-Traffic',':=','20480');

mysql> INSERT INTO radgroupcheck (groupname,attribute,op,VALUE) VALUES ('user','Simultaneous-Use',':=','1');

acct-interim-interval是计算流量的间隔（600秒），意味着每隔10分钟记录当前流量;

Max-Monthly-Traffic是每月最大流量，这里是20G（单位是M）;

radgroupcheck表的Simultaneous-Use表示单个用户的同时连接数目;

这里要格外注意的是，许多网络上的文章介绍Max-Monthly-Traffic单位为字节，数值为5368709102，换算一下大概5G左右，而如果我们也精确到字节，数值设为20G，也就是21474836480，则用户拨入进行身份验证的时候将会报错。因而此次我们将流量限制的精度单位修改为M。详细可参考如下链接介绍：http://www.xj123.info/2856.html

二、修改配置文件

1、修改/etc/raddb/sites-enabled/default文件，添加流量限制的reject条件

# vi /etc/raddb/sites-enabled/default

#找到authorize一节插入如下内容：

update request {

Group-Name := "%{sql:SELECT groupname FROM radusergroup WHERE username='%{User-Name}' ORDER BY priority}"

}

if ("%{sql: SELECT SUM(acctinputoctets+acctoutputoctets) div 1048576 FROM radacct WHERE username='%{User-Name}' AND date_format(acctstarttime, '%Y-%m-%d') >= date_format(now(),'%Y-%m-01') AND date_format(acctstoptime, '%Y-%m-%d') <= last_day(now());}" >= "%{sql: SELECT value FROM radgroupreply WHERE groupname='%{Group-Name}' AND attribute='Max-Monthly-Traffic';}") {

reject

}

2、由于使用了非内置的attribute Max-Monthly-Traffic，所以需要在/etc/raddb/dictionary里面定义

1 2	`# tail -1 /etc/raddb/dictionary` `ATTRIBUTE Max-Monthly-Traffic 3003 integer`

3、修改/etc/raddb/sql/mysql/dialup.conf文件，开启在线用户数检查

# vi /etc/raddb/sql/mysql/dialup.conf

sql_user_name = "%{%{Stripped-User-Name}:-%{%{User-Name}:-DEFAULT}}"

#sql_user_name = "%{User-Name}" #注释掉这行

# Uncomment simul_count_query to enable simultaneous use checking

simul_count_query = "SELECT COUNT(*) \

FROM ${acct_table1} \

WHERE username = '%{SQL-User-Name}' \

AND acctstoptime IS NULL"

simul_verify_query = "SELECT radacctid, acctsessionid, username, \

nasipaddress, nasportid, framedipaddress, \

callingstationid, framedprotocol \

FROM ${acct_table1} \

WHERE username = '%{SQL-User-Name}' \

AND acctstoptime IS NULL"

三、重启服务

# /etc/init.d/radiusd stop

# /etc/init.d/pptpd restart

四、测试

1、将rediusd服务运行在debug模式下，进行拨号测试，主要测试流量控制！

#radiusd -X

通过上面可以看到当前的用户流量消耗为2M，限制流量的值为20480M。

因而在/etc/raddb/sites-enabled/default文件，判断流量限制的reject条件的结果为false,用户可以通过验证，完成拨号！下面是详细的拨号日志：

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rad_recv: Access-Request packet from host 127.0.0.1 port 49226, id=94, length=150

Service-Type = Framed-User

Framed-Protocol = PPP

User-Name = "ptest1"

MS-CHAP-Challenge = 0x6716c32940f1c84ad213d2d52df1712d

MS-CHAP2-Response = 0x2400c77c090296803fb3c0822b8c679547f000000000000000001eb41fe8e518c1f756fb5d9d5904ddb8dc1fe271e98aa055

Calling-Station-Id = "27.151.123.121"

NAS-IP-Address = 127.0.0.1

NAS-Port = 0

# Executing section authorize from file /etc/raddb/sites-enabled/default

+group authorize {

++update request {

sql_xlat

expand: %{Stripped-User-Name} ->

... expanding second conditional

expand: %{User-Name} -> ptest1

expand: %{%{User-Name}:-DEFAULT} -> ptest1

expand: %{%{Stripped-User-Name}:-%{%{User-Name}:-DEFAULT}} -> ptest1

sql_set_user escaped user --> 'ptest1'

expand: SELECT groupname FROM radusergroup WHERE username='%{User-Name}' ORDER BY priority -> SELECT groupname FROM radusergroup WHERE username='ptest1' ORDER BY priority

rlm_sql (sql): Reserving sql socket id: 30

sql_xlat finished

rlm_sql (sql): Released sql socket id: 30

expand: %{sql:SELECT groupname FROM radusergroup WHERE username='%{User-Name}' ORDER BY priority} -> user

++} # update request = noop

++? if ("%{sql: SELECT SUM(acctinputoctets+acctoutputoctets) div 1048576 FROM radacct WHERE username='%{User-Name}' AND date_format(acctstarttime, '%Y-%m-%d') >= date_format(now(),'%Y-%m-01') AND date_format(acctstoptime, '%Y-%m-%d') <= last_day(now());}" >= "%{sql: SELECT value FROM radgroupreply WHERE groupname='%{Group-Name}' AND attribute='Max-Monthly-Traffic';}")

sql_xlat

expand: %{Stripped-User-Name} ->

... expanding second conditional

expand: %{User-Name} -> ptest1

expand: %{%{User-Name}:-DEFAULT} -> ptest1

expand: %{%{Stripped-User-Name}:-%{%{User-Name}:-DEFAULT}} -> ptest1

sql_set_user escaped user --> 'ptest1'

expand:  SELECT SUM(acctinputoctets+acctoutputoctets) div 1048576 FROM radacct WHERE username='%{User-Name}' AND date_format(acctstarttime, '%Y-%m-%d') >= date_format(now(),'%Y-%m-01') AND date_format(acctstoptime, '%Y-%m-%d') <= last_day(now()); ->  SELECT SUM(acctinputoctets+acctoutputoctets) div 1048576 FROM radacct WHERE username='ptest1' AND date_format(acctstarttime, '2016-06-30') >= date_format(now(),'2016-06-01') AND date_format(acctstoptime, '2016-06-30') <= last_day(now());

rlm_sql (sql): Reserving sql socket id: 29

sql_xlat finished

rlm_sql (sql): Released sql socket id: 29

expand: %{sql: SELECT SUM(acctinputoctets+acctoutputoctets) div 1048576 FROM radacct WHERE username='%{User-Name}' AND date_format(acctstarttime, '%Y-%m-%d') >= date_format(now(),'%Y-%m-01') AND date_format(acctstoptime, '%Y-%m-%d') <= last_day(now());} -> 2

sql_xlat

expand: %{Stripped-User-Name} ->

... expanding second conditional

expand: %{User-Name} -> ptest1

expand: %{%{User-Name}:-DEFAULT} -> ptest1

expand: %{%{Stripped-User-Name}:-%{%{User-Name}:-DEFAULT}} -> ptest1

sql_set_user escaped user --> 'ptest1'

expand:  SELECT value FROM radgroupreply WHERE groupname='%{Group-Name}' AND attribute='Max-Monthly-Traffic'; ->  SELECT value FROM radgroupreply WHERE groupname='user' AND attribute='Max-Monthly-Traffic';

rlm_sql (sql): Reserving sql socket id: 28

sql_xlat finished

rlm_sql (sql): Released sql socket id: 28

expand: %{sql: SELECT value FROM radgroupreply WHERE groupname='%{Group-Name}' AND attribute='Max-Monthly-Traffic';} -> 20480

? Evaluating ("%{sql: SELECT SUM(acctinputoctets+acctoutputoctets) div 1048576 FROM radacct WHERE username='%{User-Name}' AND date_format(acctstarttime, '%Y-%m-%d') >= date_format(now(),'%Y-%m-01') AND date_format(acctstoptime, '%Y-%m-%d') <= last_day(now());}" >= "%{sql: SELECT value FROM radgroupreply WHERE groupname='%{Group-Name}' AND attribute='Max-Monthly-Traffic';}") -> FALSE

++? if ("%{sql: SELECT SUM(acctinputoctets+acctoutputoctets) div 1048576 FROM radacct WHERE username='%{User-Name}' AND date_format(acctstarttime, '%Y-%m-%d') >= date_format(now(),'%Y-%m-01') AND date_format(acctstoptime, '%Y-%m-%d') <= last_day(now());}" >= "%{sql: SELECT value FROM radgroupreply WHERE groupname='%{Group-Name}' AND attribute='Max-Monthly-Traffic';}") -> FALSE

++[preprocess] = ok

++[chap] = noop

[mschap] Found MS-CHAP attributes. Setting 'Auth-Type = mschap'

++[mschap] = ok

++[digest] = noop

[suffix] No '@' in User-Name = "ptest1", looking up realm NULL

[suffix] No such realm "NULL"

++[suffix] = noop

[eap] No EAP-Message, not doing EAP

++[eap] = noop

[sql] expand: %{Stripped-User-Name} ->

[sql] ... expanding second conditional

[sql] expand: %{User-Name} -> ptest1

[sql] expand: %{%{User-Name}:-DEFAULT} -> ptest1

[sql] expand: %{%{Stripped-User-Name}:-%{%{User-Name}:-DEFAULT}} -> ptest1

[sql] sql_set_user escaped user --> 'ptest1'

rlm_sql (sql): Reserving sql socket id: 27

[sql]   expand: SELECT id, username, attribute, value, op           FROM radcheck           WHERE username = '%{SQL-User-Name}'           ORDER BY id -> SELECT id, username, attribute, value, op           FROM radcheck           WHERE username = 'ptest1'           ORDER BY id

WARNING: Found User-Password == "...".

WARNING: Are you sure you don't mean Cleartext-Password?

WARNING: See "man rlm_pap" for more information.

[sql] User found in radcheck table

[sql]   expand: SELECT id, username, attribute, value, op           FROM radreply           WHERE username = '%{SQL-User-Name}'           ORDER BY id -> SELECT id, username, attribute, value, op           FROM radreply           WHERE username = 'ptest1'           ORDER BY id

[sql]   expand: SELECT groupname           FROM radusergroup           WHERE username = '%{SQL-User-Name}'           ORDER BY priority -> SELECT groupname           FROM radusergroup           WHERE username = 'ptest1'           ORDER BY priority

[sql]   expand: SELECT id, groupname, attribute,           Value, op           FROM radgroupcheck           WHERE groupname = '%{Sql-Group}'           ORDER BY id -> SELECT id, groupname, attribute,           Value, op           FROM radgroupcheck           WHERE groupname = 'user'           ORDER BY id

[sql] User found in group user

[sql]   expand: SELECT id, groupname, attribute,           value, op           FROM radgroupreply           WHERE groupname = '%{Sql-Group}'           ORDER BY id -> SELECT id, groupname, attribute,           value, op           FROM radgroupreply           WHERE groupname = 'user'           ORDER BY id

rlm_sql (sql): Released sql socket id: 27

++[sql] = ok

++[expiration] = noop

++[logintime] = noop

[pap] WARNING: Auth-Type already set. Not setting to PAP

++[pap] = noop

+} # group authorize = ok

Found Auth-Type = MSCHAP

!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

!!! Replacing User-Password in config items with Cleartext-Password. !!!

!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

!!! Please update your configuration so that the "known good" !!!

!!! clear text password is in Cleartext-Password, and not in User-Password. !!!

!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

# Executing group from file /etc/raddb/sites-enabled/default

+group MS-CHAP {

[mschap] Creating challenge hash with username: ptest1

[mschap] Client is using MS-CHAPv2 for ptest1, we need NT-Password

[mschap] adding MS-CHAPv2 MPPE keys

++[mschap] = ok

+} # group MS-CHAP = ok

# Executing section session from file /etc/raddb/sites-enabled/default

+group session {

[radutmp] expand: /var/log/radius/radutmp -> /var/log/radius/radutmp

++[radutmp] = ok

+} # group session = ok

# Executing section post-auth from file /etc/raddb/sites-enabled/default

+group post-auth {

[sql] expand: %{Stripped-User-Name} ->

[sql] ... expanding second conditional

[sql] expand: %{User-Name} -> ptest1

[sql] expand: %{%{User-Name}:-DEFAULT} -> ptest1

[sql] expand: %{%{Stripped-User-Name}:-%{%{User-Name}:-DEFAULT}} -> ptest1

[sql] sql_set_user escaped user --> 'ptest1'

[sql] expand: %{User-Password} ->

[sql] ... expanding second conditional

[sql] expand: %{Chap-Password} ->

[sql]   expand: INSERT INTO radpostauth                           (username, pass, reply, authdate)                           VALUES (                           '%{User-Name}',                           '%{%{User-Password}:-%{Chap-Password}}',                           '%{reply:Packet-Type}', '%S') -> INSERT INTO radpostauth                           (username, pass, reply, authdate)                           VALUES (                           'ptest1',                           '',                           'Access-Accept', '2016-06-30 13:05:14')

rlm_sql (sql) in sql_postauth: query is INSERT INTO radpostauth                           (username, pass, reply, authdate)                           VALUES (                           'ptest1',                           '',                           'Access-Accept', '2016-06-30 13:05:14')

rlm_sql (sql): Reserving sql socket id: 26

rlm_sql (sql): Released sql socket id: 26

++[sql] = ok

++[exec] = noop

+} # group post-auth = ok

Sending Access-Accept of id 94 to 127.0.0.1 port 49226

Service-Type := Framed-User

Framed-IP-Address := 255.255.255.255

Framed-IP-Netmask := 255.255.255.0

Acct-Interim-Interval := 600

MS-CHAP2-Success = 0x24533d46303044303641413737333432343231363234364143413245333041373133433531344439353037

MS-MPPE-Recv-Key = 0x3373da01475488084e5f82abae7cbda8

MS-MPPE-Send-Key = 0xdb408d5d7f18d9fd38e6c1888b8c0b13

MS-MPPE-Encryption-Policy = 0x00000001

MS-MPPE-Encryption-Types = 0x00000006

Finished request 0.

Going to the next request

Waking up in 4.9 seconds.

Cleaning up request 0 ID 94 with timestamp +88

Ready to process requests.

rad_recv: Accounting-Request packet from host 127.0.0.1 port 58801, id=95, length=114

Acct-Session-Id = "5774A890092400"

User-Name = "ptest1"

Acct-Status-Type = Start

Service-Type = Framed-User

Framed-Protocol = PPP

Calling-Station-Id = "27.151.123.121"

Acct-Authentic = RADIUS

NAS-Port-Type = Async

Framed-IP-Address = 192.168.222.10

NAS-IP-Address = 127.0.0.1

NAS-Port = 0

Acct-Delay-Time = 0

# Executing section preacct from file /etc/raddb/sites-enabled/default

+group preacct {

++[preprocess] = ok

[acct_unique] WARNING: Attribute NAS-Identifier was not found in request, unique ID MAY be inconsistent

[acct_unique] Hashing 'NAS-Port = 0,,NAS-IP-Address = 127.0.0.1,Acct-Session-Id = "5774A890092400",User-Name = "ptest1"'

[acct_unique] Acct-Unique-Session-ID = "413ac0cc5b5f4759".

++[acct_unique] = ok

[suffix] No '@' in User-Name = "ptest1", looking up realm NULL

[suffix] No such realm "NULL"

++[suffix] = noop

+} # group preacct = ok

# Executing section accounting from file /etc/raddb/sites-enabled/default

+group accounting {

[detail] expand: %{Packet-Src-IP-Address} -> 127.0.0.1

[detail]        expand: /var/log/radius/radacct/%{%{Packet-Src-IP-Address}:-%{Packet-Src-IPv6-Address}}/detail-%Y%m%d -> /var/log/radius/radacct/127.0.0.1/detail-20160630

[detail] /var/log/radius/radacct/%{%{Packet-Src-IP-Address}:-%{Packet-Src-IPv6-Address}}/detail-%Y%m%d expands to /var/log/radius/radacct/127.0.0.1/detail-20160630

[detail] expand: %t -> Thu Jun 30 13:05:20 2016

++[detail] = ok

[sql] expand: %{Stripped-User-Name} ->

[sql] ... expanding second conditional

[sql] expand: %{User-Name} -> ptest1

[sql] expand: %{%{User-Name}:-DEFAULT} -> ptest1

[sql] expand: %{%{Stripped-User-Name}:-%{%{User-Name}:-DEFAULT}} -> ptest1

[sql] sql_set_user escaped user --> 'ptest1'

[sql] expand: %{Acct-Delay-Time} -> 0

[sql]   expand:            INSERT INTO radacct             (acctsessionid,    acctuniqueid,     username,              realm,            nasipaddress,     nasportid,              nasporttype,      acctstarttime,    acctstoptime,              acctsessiontime,  acctauthentic,    connectinfo_start,              connectinfo_stop, acctinputoctets,  acctoutputoctets,              calledstationid,  callingstationid, acctterminatecause,              servicetype,      framedprotocol,   framedipaddress,              acctstartdelay,   acctstopdelay,    xascendsessionsvrkey)           VALUES             ('%{Acct-Session-Id}', '%{Acct-Unique-Session-Id}',              '%{SQL-User-Name}',              '%{Realm}', '%{NAS-IP-Address}', '%{NAS-Port}',              '%{NAS-Port-Type}', '%S', NULL,              '0', '%{Acct-Authentic}', '%{Connect-Info}',              '', '0', '0',              '%{Called-Station-Id}', '%{Calling-Station-Id}', '',              '%{Service-Type}', '%{Framed-Protocol}', '%{Framed-IP-Address}',

rlm_sql (sql): Reserving sql socket id: 25

rlm_sql (sql): Released sql socket id: 25

++[sql] = ok

++[exec] = noop

[attr_filter.accounting_response] expand: %{User-Name} -> ptest1

attr_filter: Matched entry DEFAULT at line 12

++[attr_filter.accounting_response] = updated

+} # group accounting = updated

Sending Accounting-Response of id 95 to 127.0.0.1 port 58801

Finished request 1.

Cleaning up request 1 ID 95 with timestamp +94

Going to the next request

Ready to process requests.

2、测试同一个VPN账号，多终端登录

通过如下sql语句可以看到当前用户的拨号连接情况，很明显通过前面的配置，并没有起到限制的效果。

1 2	`mysql> SELECT radacctid, acctsessionid, username,nasipaddress, nasportid, framedipaddress, callingstationid, framedprotocol FROM radacct WHERE username ='yang' AND acctstoptime IS NULL;` `mysql> SELECT COUNT(*) from radacct WHERE username ='yang' AND acctstoptime IS NULL;`

通过修改/etc/raddb/sites-enabled/default文件，注释掉session节的radutmp配置，重启radiusd服务后测试，发现效果符合预期

# vi /etc/raddb/sites-enabled/default

同一个账号的第二个拨号连接就会直接提示验证失败！

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