2 # Written by Marco Bonetti & Mike Perry
3 # Based on instructions from Dan Singletary's ADSL BW Management HOWTO:
4 # http://www.faqs.org/docs/Linux-HOWTO/ADSL-Bandwidth-Management-HOWTO.html
5 # This script is Public Domain.
7 ############################### README #################################
9 # This script provides prioritization of Tor traffic below other
10 # traffic on a Linux server. It has two modes of operation: UID based
11 # and IP based. The UID based method requires that Tor be launched from
12 # a specific user ID. The "User" and "Group" Tor config settings are
13 # insufficient, as they set the UID after the socket is created.
14 # Here is a three line C wrapper you can use to execute Tor and drop
15 # privs to UID 501 before it creates any sockets. Change the UID
16 # to the UID for your tor server user, and compile with
17 # 'gcc tor_wrap.c -o tor_wrap':
20 # int main(int argc, char **argv) {
21 # if(setresuid(501, 501, 501) == -1) { perror("setresuid"); return 1; }
22 # execl("/bin/tor", "/bin/tor", "-f", "/etc/tor/torrc", NULL);
23 # perror("execl"); return 1;
26 # The IP setting requires that a separate IP address be dedicated to Tor.
27 # Your Torrc should be set to bind to this IP for "OutboundBindAddress",
28 # "ListenAddress", and "Address".
30 # You should also tune the individual connection rate parameters below
31 # to your individual connection. In particular, you should leave *some*
32 # minimum amount of bandwidth for Tor, so that Tor users are not
33 # completely choked out when you use your server's bandwidth. 30% is
34 # probably a polite choice.
36 # To start the shaping, run it as:
39 # To get status information (useful to verify packets are getting marked
40 # and prioritized), run:
41 # ./linux-tor-prio.sh status
43 # And to stop prioritization:
44 # ./linux-tor-prio.sh stop
46 ########################################################################
48 # BEGIN USER TUNABLE PARAMETERS
52 # NOTE! You must START Tor under this UID. Using the Tor User/Group
53 # config setting is NOT sufficient.
56 # If the UID mechanism doesn't work for you, you can set this parameter
57 # instead. If set, it will take precedence over the UID setting. Note that
58 # you need multiple IPs for this to work.
61 # Average ping to most places on the net, milliseconds
64 # RATE_UP must be less than your connection's upload capacity. If it is
65 # larger, then the bottleneck will be at your router's queue, which you
66 # do not control. This will cause congestion and a revert to normal TCP
67 # fairness no matter what the queing priority is.
70 # RATE_UP_TOR is the minimum speed your Tor connections will have.
71 # They will have at least this much bandwidth for upload. In general,
72 # you probably shouldn't set this too low, or else Tor users who use
73 # your node will be completely choked out whenever your machine
74 # does any other network activity. That is not very fun.
77 # RATE_UP_TOR_CEIL is the maximum rate allowed for all Tor trafic
85 AVG_PKT
=900 # should be more like 600 for non-exit nodes
87 # END USER TUNABLE PARAMETERS
89 # The queue size should be no larger than your bandwidth-delay
90 # product. This is RT latency*bandwidth/MTU/2
92 BDP
=$
(expr $RTT_LATENCY \
* $RATE_UP / $AVG_PKT)
94 # Further research indicates that the BDP calculations should use
95 # RTT/sqrt(n) where n is the expected number of active connections..
99 if [ "$1" = "status" ]
102 tc
-s qdisc show dev
$DEV
103 tc
-s qdisc show dev imq0
105 tc
-s class show dev
$DEV
106 tc
-s class show dev imq0
108 tc
-s filter show dev
$DEV
109 tc
-s filter show dev imq0
111 iptables
-t mangle
-L TORSHAPER-OUT
-v -x 2> /dev
/null
116 # Reset everything to a known state (cleared)
117 tc qdisc del dev
$DEV root
2> /dev
/null
> /dev
/null
118 tc qdisc del dev imq0 root
2> /dev
/null
> /dev
/null
119 iptables
-t mangle
-D POSTROUTING
-o $DEV -j TORSHAPER-OUT
2> /dev
/null
> /dev
/null
120 iptables
-t mangle
-D PREROUTING
-o $DEV -j TORSHAPER-OUT
2> /dev
/null
> /dev
/null
121 iptables
-t mangle
-D OUTPUT
-o $DEV -j TORSHAPER-OUT
2> /dev
/null
> /dev
/null
122 iptables
-t mangle
-F TORSHAPER-OUT
2> /dev
/null
> /dev
/null
123 iptables
-t mangle
-X TORSHAPER-OUT
2> /dev
/null
> /dev
/null
124 ip link
set imq0 down
2> /dev
/null
> /dev
/null
125 rmmod imq
2> /dev
/null
> /dev
/null
129 echo "Shaping removed on $DEV."
133 # Outbound Shaping (limits total bandwidth to RATE_UP)
135 ip link
set dev
$DEV qlen
$BDP
137 # Add HTB root qdisc, default is high prio
138 tc qdisc add dev
$DEV root handle
1: htb default
20
140 # Add main rate limit class
141 tc class add dev
$DEV parent
1: classid
1:1 htb rate
${RATE_UP}kbit
143 # Create the two classes, giving Tor at least RATE_UP_TOR kbit and capping
144 # total upstream at RATE_UP so the queue is under our control.
145 tc class add dev
$DEV parent
1:1 classid
1:20 htb rate $
(expr $RATE_UP - $RATE_UP_TOR)kbit ceil
${RATE_UP}kbit prio
0
146 tc class add dev
$DEV parent
1:1 classid
1:21 htb rate $
[$RATE_UP_TOR]kbit ceil
${RATE_UP_TOR_CEIL}kbit prio
10
149 tc qdisc add dev
$DEV parent
1:20 handle
20: pfifo limit
$BDP
150 tc qdisc add dev
$DEV parent
1:21 handle
21: pfifo limit
$BDP
152 # filter traffic into classes by fwmark
153 tc filter add dev
$DEV parent
1:0 prio
0 protocol ip handle
20 fw flowid
1:20
154 tc filter add dev
$DEV parent
1:0 prio
0 protocol ip handle
21 fw flowid
1:21
156 # add TORSHAPER-OUT chain to the mangle table in iptables
157 iptables
-t mangle
-N TORSHAPER-OUT
158 iptables
-t mangle
-I $CHAIN -o $DEV -j TORSHAPER-OUT
162 # Low priority to Tor
163 if [ ""$TOR_IP == "" ]
165 echo "Using UID-based QoS. UID $TOR_UID marked as low priority."
166 iptables
-t mangle
-A TORSHAPER-OUT
-m owner
--uid-owner $TOR_UID -j MARK
--set-mark 21
168 echo "Using IP-based QoS. $TOR_IP marked as low priority."
169 iptables
-t mangle
-A TORSHAPER-OUT
-s $TOR_IP -j MARK
--set-mark 21
172 # High prio for everything else
173 iptables
-t mangle
-A TORSHAPER-OUT
-m mark
--mark 0 -j MARK
--set-mark 20
175 echo "Outbound shaping added to $DEV. Rate for Tor upload at least: ${RATE_UP_TOR}Kbyte/sec."