VPN et routage

Bonjour,

Mon but est de réaliser ceci :

http://img21.imageshack.us/img21/5295/visiodessin2.png

J’ai installé le serveur openvpn sur l’ordinateur SCSERVER

L’ordinateur portable DELL est connecté grâce à une clé 3G

Cependant, j’aimerais bien que ces conditions soit rempli

  • Lorsqu’un ordinateur externe se connecte de l’extérieur, il prend un adresse en 10.8.0.x (fonctionne)
  • Que le routage soit transparent. C’est à dire que si je me trouve sur un ordinateur appartenant au réseau 192.168.1.0 et que je veux accéder au réseau 192.168.11.0, cela se fasse de manière complètement transparente. Même sur l’ordinateur portable (ne fonctionne pas).

Donc je n’arrive pas à correctement utiliser mes routes.

Ceci dit, si je suis sur l’ordinateur DELL, je peux pinguer les adresses 10.8.1.253 et 192.168.1.253 de l’ordinateur SCSERVER mais les autres adresses du réseau

L’ordinateur SCSERVER est une debian squeeze de configuration suivante :

2x1Gbps - 2Gb DDR - P4 3Ghz

L’ip forwarding est bien activé

SCSERVER:/home/flamme# cat /proc/sys/net/ipv4/ip_forward 1

Voici les routes du SCSERVER :

SCSERVER:/home/flamme# route Table de routage IP du noyau Destination Passerelle Genmask Indic Metric Ref Use Iface localnet * 255.255.255.0 U 0 0 0 eth0 localnet * 255.255.255.0 U 0 0 0 eth1 10.8.0.0 * 255.255.0.0 U 0 0 0 tun0 default 192.168.1.254 0.0.0.0 UG 0 0 0 eth1 default 192.168.1.254 0.0.0.0 UG 0 0 0 eth0

Et voici le fichier de configuration d’openvpn (server.conf)

[code]SCSERVER:/home/flamme# cat /etc/openvpn/server.conf
#################################################

Sample OpenVPN 2.0 config file for

multi-client server.

This file is for the server side

of a many-clients <-> one-server

OpenVPN configuration.

OpenVPN also supports

single-machine <-> single-machine

configurations (See the Examples page

on the web site for more info).

This config should work on Windows

or Linux/BSD systems. Remember on

Windows to quote pathnames and use

double backslashes, e.g.:

“C:\Program Files\OpenVPN\config\foo.key”

Comments are preceded with ‘#’ or ‘;’

#################################################

Which local IP address should OpenVPN

listen on? (optional)

;local a.b.c.d

Which TCP/UDP port should OpenVPN listen on?

If you want to run multiple OpenVPN instances

on the same machine, use a different port

number for each one. You will need to

open up this port on your firewall.

port 1194

TCP or UDP server?

proto tcp
#proto udp

“dev tun” will create a routed IP tunnel,

“dev tap” will create an ethernet tunnel.

Use “dev tap0” if you are ethernet bridging

and have precreated a tap0 virtual interface

and bridged it with your ethernet interface.

If you want to control access policies

over the VPN, you must create firewall

rules for the the TUN/TAP interface.

On non-Windows systems, you can give

an explicit unit number, such as tun0.

On Windows, use “dev-node” for this.

On most systems, the VPN will not function

unless you partially or fully disable

the firewall for the TUN/TAP interface.

;dev tap
dev tun

Windows needs the TAP-Win32 adapter name

from the Network Connections panel if you

have more than one. On XP SP2 or higher,

you may need to selectively disable the

Windows firewall for the TAP adapter.

Non-Windows systems usually don’t need this.

;dev-node MyTap

SSL/TLS root certificate (ca), certificate

(cert), and private key (key). Each client

and the server must have their own cert and

key file. The server and all clients will

use the same ca file.

See the “easy-rsa” directory for a series

of scripts for generating RSA certificates

and private keys. Remember to use

a unique Common Name for the server

and each of the client certificates.

Any X509 key management system can be used.

OpenVPN can also use a PKCS #12 formatted key file

(see “pkcs12” directive in man page).

ca ca.crt
cert scserver.org.crt
key scserver.org.key # This file should be kept secret

Diffie hellman parameters.

Generate your own with:

openssl dhparam -out dh1024.pem 1024

Substitute 2048 for 1024 if you are using

2048 bit keys.

dh dh1024.pem

Configure server mode and supply a VPN subnet

for OpenVPN to draw client addresses from.

The server will take 10.8.0.1 for itself,

the rest will be made available to clients.

Each client will be able to reach the server

on 10.8.0.1. Comment this line out if you are

ethernet bridging. See the man page for more info.

server 10.8.0.0 255.255.0.0

Maintain a record of client <-> virtual IP address

associations in this file. If OpenVPN goes down or

is restarted, reconnecting clients can be assigned

the same virtual IP address from the pool that was

previously assigned.

ifconfig-pool-persist ipp.txt

Configure server mode for ethernet bridging.

You must first use your OS’s bridging capability

to bridge the TAP interface with the ethernet

NIC interface. Then you must manually set the

IP/netmask on the bridge interface, here we

assume 10.8.0.4/255.255.255.0. Finally we

must set aside an IP range in this subnet

(start=10.8.0.50 end=10.8.0.100) to allocate

to connecting clients. Leave this line commented

out unless you are ethernet bridging.

;server-bridge 10.8.0.4 255.255.255.0 10.8.0.50 10.8.0.100

Configure server mode for ethernet bridging

using a DHCP-proxy, where clients talk

to the OpenVPN server-side DHCP server

to receive their IP address allocation

and DNS server addresses. You must first use

your OS’s bridging capability to bridge the TAP

interface with the ethernet NIC interface.

Note: this mode only works on clients (such as

Windows), where the client-side TAP adapter is

bound to a DHCP client.

;server-bridge

Push routes to the client to allow it

to reach other private subnets behind

the server. Remember that these

private subnets will also need

to know to route the OpenVPN client

address pool (10.8.0.0/255.255.255.0)

back to the OpenVPN server.

push “route 192.168.1.0 255.255.255.0”
;push “route 192.168.20.0 255.255.255.0”

To assign specific IP addresses to specific

clients or if a connecting client has a private

subnet behind it that should also have VPN access,

use the subdirectory “ccd” for client-specific

configuration files (see man page for more info).

EXAMPLE: Suppose the client

having the certificate common name “Thelonious”

also has a small subnet behind his connecting

machine, such as 192.168.40.128/255.255.255.248.

First, uncomment out these lines:

;client-config-dir ccd
;route 192.168.40.128 255.255.255.248

Then create a file ccd/Thelonious with this line:

iroute 192.168.40.128 255.255.255.248

This will allow Thelonious’ private subnet to

access the VPN. This example will only work

if you are routing, not bridging, i.e. you are

using “dev tun” and “server” directives.

EXAMPLE: Suppose you want to give

Thelonious a fixed VPN IP address of 10.9.0.1.

First uncomment out these lines:

client-config-dir ccd
route 10.8.0.0 255.255.255.0
route 192.168.1.0 255.255.255.0

Then add this line to ccd/Thelonious:

ifconfig-push 10.9.0.1 10.9.0.2

Suppose that you want to enable different

firewall access policies for different groups

of clients. There are two methods:

(1) Run multiple OpenVPN daemons, one for each

group, and firewall the TUN/TAP interface

for each group/daemon appropriately.

(2) (Advanced) Create a script to dynamically

modify the firewall in response to access

from different clients. See man

page for more info on learn-address script.

;learn-address ./script

If enabled, this directive will configure

all clients to redirect their default

network gateway through the VPN, causing

all IP traffic such as web browsing and

and DNS lookups to go through the VPN

(The OpenVPN server machine may need to NAT

or bridge the TUN/TAP interface to the internet

in order for this to work properly).

;push “redirect-gateway def1 bypass-dhcp”

Certain Windows-specific network settings

can be pushed to clients, such as DNS

or WINS server addresses. CAVEAT:

http://openvpn.net/faq.html#dhcpcaveats

The addresses below refer to the public

DNS servers provided by opendns.com.

;push “dhcp-option DNS 208.67.222.222”
;push “dhcp-option DNS 208.67.220.220”

Uncomment this directive to allow different

clients to be able to “see” each other.

By default, clients will only see the server.

To force clients to only see the server, you

will also need to appropriately firewall the

server’s TUN/TAP interface.

client-to-client

Uncomment this directive if multiple clients

might connect with the same certificate/key

files or common names. This is recommended

only for testing purposes. For production use,

each client should have its own certificate/key

pair.

IF YOU HAVE NOT GENERATED INDIVIDUAL

CERTIFICATE/KEY PAIRS FOR EACH CLIENT,

EACH HAVING ITS OWN UNIQUE “COMMON NAME”,

UNCOMMENT THIS LINE OUT.

;duplicate-cn

The keepalive directive causes ping-like

messages to be sent back and forth over

the link so that each side knows when

the other side has gone down.

Ping every 10 seconds, assume that remote

peer is down if no ping received during

a 120 second time period.

keepalive 10 120

For extra security beyond that provided

by SSL/TLS, create an “HMAC firewall”

to help block DoS attacks and UDP port flooding.

Generate with:

openvpn --genkey --secret ta.key

The server and each client must have

a copy of this key.

The second parameter should be ‘0’

on the server and ‘1’ on the clients.

;tls-auth ta.key 0 # This file is secret

Select a cryptographic cipher.

This config item must be copied to

the client config file as well.

;cipher BF-CBC # Blowfish (default)
cipher AES-128-CBC # AES
;cipher DES-EDE3-CBC # Triple-DES

Enable compression on the VPN link.

If you enable it here, you must also

enable it in the client config file.

comp-lzo

The maximum number of concurrently connected

clients we want to allow.

;max-clients 100

It’s a good idea to reduce the OpenVPN

daemon’s privileges after initialization.

You can uncomment this out on

non-Windows systems.

;user nobody
;group nogroup

The persist options will try to avoid

accessing certain resources on restart

that may no longer be accessible because

of the privilege downgrade.

persist-key
persist-tun

Output a short status file showing

current connections, truncated

and rewritten every minute.

status openvpn-status.log

By default, log messages will go to the syslog (or

on Windows, if running as a service, they will go to

the “\Program Files\OpenVPN\log” directory).

Use log or log-append to override this default.

“log” will truncate the log file on OpenVPN startup,

while “log-append” will append to it. Use one

or the other (but not both).

;log openvpn.log
;log-append openvpn.log

Set the appropriate level of log

file verbosity.

0 is silent, except for fatal errors

4 is reasonable for general usage

5 and 6 can help to debug connection problems

9 is extremely verbose

verb 3

Silence repeating messages. At most 20

sequential messages of the same message

category will be output to the log.

;mute 20[/code]

Donc voilà…

Pouvez m’aider à réaliser cette tâche ?

Merci beaucoup.

Petit up :wink:

UP

Il faut être plus précis, c’est un problème de routage, donc que donne
route -n sur
le portable extérieur?
le serveur VPN?
Une machine de 192.168.1.0 et 192.168.11.0

Par ailleurs, la route de ton serveur avec deux interfaces sur le même réseau est aberrante: seule une interface est utilisée (la première de la table soit ici eth1).

Merci beaucoup de ta réponse; donc pour répondre à test questions :

Le portable extérieur est une machine windows et voici ce que donne un route print :

[code]===========================================================================

Itinéraires actifs :
Destination réseau Masque réseau Adr. passerelle Adr. interface Métrique
0.0.0.0 0.0.0.0 10.220.20.67 10.220.20.67 1
10.8.0.0 255.255.0.0 10.8.0.33 10.8.0.34 1
10.8.0.32 255.255.255.252 10.8.0.34 10.8.0.34 30
10.8.0.34 255.255.255.255 127.0.0.1 127.0.0.1 30
10.220.20.67 255.255.255.255 127.0.0.1 127.0.0.1 50
10.255.255.255 255.255.255.255 10.8.0.34 10.8.0.34 30
10.255.255.255 255.255.255.255 10.220.20.67 10.220.20.67 50
127.0.0.0 255.0.0.0 127.0.0.1 127.0.0.1 1
169.254.1.1 255.255.255.255 10.220.20.67 10.220.20.67 1
192.168.1.0 255.255.255.0 10.8.0.33 10.8.0.34 1
224.0.0.0 240.0.0.0 10.8.0.34 10.8.0.34 30
224.0.0.0 240.0.0.0 10.220.20.67 10.220.20.67 1
255.255.255.255 255.255.255.255 10.8.0.34 2 1
255.255.255.255 255.255.255.255 10.8.0.34 10.8.0.34 1
255.255.255.255 255.255.255.255 10.220.20.67 10.220.20.67 1
Passerelle par défaut : 10.220.20.67

Itinéraires persistants :
Aucun[/code]

La route print à été prise lorsque l’ordinateur est connecté au serveur vpn par le biais du réseau mobile.

SCSERVER:~# route -n Table de routage IP du noyau Destination Passerelle Genmask Indic Metric Ref Use Iface 192.168.1.0 0.0.0.0 255.255.255.0 U 0 0 0 eth0 192.168.1.0 0.0.0.0 255.255.255.0 U 0 0 0 eth1 10.8.0.0 0.0.0.0 255.255.0.0 U 0 0 0 tun0 0.0.0.0 192.168.1.254 0.0.0.0 UG 0 0 0 eth1 0.0.0.0 192.168.1.254 0.0.0.0 UG 0 0 0 eth0

Je t’envoi ça dès que possible.

La machine en 11.253

BACKUP:/home/flamme# route -n Table de routage IP du noyau Destination Passerelle Genmask Indic Metric Ref Use Iface 10.8.1.253 0.0.0.0 255.255.255.255 UH 0 0 0 tun0 192.168.1.0 10.8.1.253 255.255.255.0 UG 0 0 0 tun0 192.168.11.0 0.0.0.0 255.255.255.0 U 0 0 0 eth0 10.8.0.0 10.8.1.253 255.255.0.0 UG 0 0 0 tun0 0.0.0.0 192.168.11.254 0.0.0.0 UG 0 0 0 eth0 BACKUP:/home/flamme# ping 192.168.1.254 PING 192.168.1.254 (192.168.1.254) 56(84) bytes of data. ^C --- 192.168.1.254 ping statistics --- 4 packets transmitted, 0 received, 100% packet loss, time 2999ms

En fait j’ai 2 cartes réseaux qui à la base devait servir distinctement. Elles devais servir à donner une redondance (grâce au bonding). Le problème c’est que quand j’active cette fonctionnalité je perds beaucoup en débit ce qui n’est pas très logique en soit. Le but étant la redondance + l’augmentation du débit. J’ai pourtant bien un switch 802.1.q. Enfin du coût j’ai laissé comme cela et ne me suis plus re-penché sur le problème depuis.

petit up :083

Je m’y paume un peu dans tes IPs (surtout sur la windws), tu peux mettre les ifconfig (ipconfig pour windows) avec?

Bonjour,

Désolé du retard de la réponse. Voici ce que tu me demande :

SCSERVER ifconfig :

[code]eth0 Link encap:Ethernet HWaddr 00:1d:1a:05:24:e4
inet adr:192.168.1.253 Bcast:192.168.1.255 Masque:255.255.255.0
adr inet6: fe80::21d:1aff:fe05:24e4/64 Scope:Lien
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:322746769 errors:0 dropped:682 overruns:0 frame:0
TX packets:364404626 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 lg file transmission:1000
RX bytes:425976005578 (396.7 GiB) TX bytes:216554785270 (201.6 GiB)
Interruption:17 Adresse de base:0x8000

eth1 Link encap:Ethernet HWaddr 00:01:6c:ad:8c:da
inet adr:192.168.1.252 Bcast:192.168.1.255 Masque:255.255.255.0
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:0 errors:0 dropped:0 overruns:0 frame:0
TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 lg file transmission:1000
RX bytes:0 (0.0 B) TX bytes:0 (0.0 B)
Interruption:19 Adresse de base:0xfc00

lo Link encap:Boucle locale
inet adr:127.0.0.1 Masque:255.0.0.0
adr inet6: ::1/128 Scope:Hôte
UP LOOPBACK RUNNING MTU:16436 Metric:1
RX packets:529287 errors:0 dropped:0 overruns:0 frame:0
TX packets:529287 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 lg file transmission:0
RX bytes:85633448 (81.6 MiB) TX bytes:85633448 (81.6 MiB)

tun0 Link encap:UNSPEC HWaddr 00-00-00-00-00-00-00-00-00-00-00-00-00-00-00-00
inet adr:10.8.1.253 P-t-P:10.8.1.253 Masque:255.255.0.0
UP POINTOPOINT RUNNING NOARP MULTICAST MTU:1500 Metric:1
RX packets:502 errors:0 dropped:0 overruns:0 frame:0
TX packets:308 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 lg file transmission:100
RX bytes:42261 (41.2 KiB) TX bytes:31839 (31.0 KiB)[/code]

SCSERVER route :

SCSERVER:/home/flamme# route
Table de routage IP du noyau
Destination     Passerelle      Genmask         Indic Metric Ref    Use Iface
localnet        *               255.255.255.0   U     0      0        0 eth0
localnet        *               255.255.255.0   U     0      0        0 eth1
10.8.0.0        *               255.255.0.0     U     0      0        0 tun0
default         192.168.1.254   0.0.0.0         UG    0      0        0 eth1
default         192.168.1.254   0.0.0.0         UG    0      0        0 eth0
SCSERVER:/home/flamme# route -n
Table de routage IP du noyau
Destination     Passerelle      Genmask         Indic Metric Ref    Use Iface
192.168.1.0     0.0.0.0         255.255.255.0   U     0      0        0 eth0
192.168.1.0     0.0.0.0         255.255.255.0   U     0      0        0 eth1
10.8.0.0        0.0.0.0         255.255.0.0     U     0      0        0 tun0
0.0.0.0         192.168.1.254   0.0.0.0         UG    0      0        0 eth1
0.0.0.0         192.168.1.254   0.0.0.0         UG    0      0        0 eth0

DELL ipconfig :

[code]C:\Documents and Settings\Flamme_2>ipconfig

Configuration IP de Windows

Carte Ethernet Connexion au réseau local:

    Statut du média . . . . . . . . . : Média déconnecté

Carte Ethernet Connexion au réseau local 4:

    Statut du média . . . . . . . . . : Média déconnecté

Carte Ethernet Connexion au réseau local 3:

    Suffixe DNS propre à la connexion :
    Adresse IP. . . . . . . . . . . . : 10.8.0.34
    Masque de sous-réseau . . . . . . : 255.255.255.252
    Passerelle par défaut . . . . . . :

Carte PPP Orange France :

    Suffixe DNS propre à la connexion :
    Adresse IP. . . . . . . . . . . . : 10.220.22.11
    Masque de sous-réseau . . . . . . : 255.255.255.255
    Passerelle par défaut . . . . . . : 10.220.22.11

[/code]

DELL route print :

[code]C:\Documents and Settings\Flamme_2>route print

Liste d’Interfaces
0x1 … MS TCP Loopback interface
0x2 …00 b0 d0 88 f4 21 … Contr¶leur Fast Ethernet intÚgrÚ 3Com 3C920 (com
patible 3C905C-TX) - Miniport d’ordonnancement de paquets
0x3 …00 ff 71 8f cf ab … TAP-Win32 Adapter V8 #2 - Miniport d’ordonnancem
ent de paquets
0x4 …00 ff 66 e9 00 a5 … TAP-Win32 Adapter V8 - Miniport d’ordonnancement
de paquets
0x20006 …00 53 45 00 00 00 … WAN (PPP/SLIP) Interface

===========================================================================
Itinéraires actifs :
Destination réseau Masque réseau Adr. passerelle Adr. interface Métrique
0.0.0.0 0.0.0.0 10.220.22.11 10.220.22.11 1
10.8.0.0 255.255.0.0 10.8.0.33 10.8.0.34 1
10.8.0.32 255.255.255.252 10.8.0.34 10.8.0.34 30
10.8.0.34 255.255.255.255 127.0.0.1 127.0.0.1 30
10.220.22.11 255.255.255.255 127.0.0.1 127.0.0.1 50
10.255.255.255 255.255.255.255 10.8.0.34 10.8.0.34 30
10.255.255.255 255.255.255.255 10.220.22.11 10.220.22.11 50
127.0.0.0 255.0.0.0 127.0.0.1 127.0.0.1 1
169.254.1.1 255.255.255.255 10.220.22.11 10.220.22.11 1
192.168.1.0 255.255.255.0 10.8.0.33 10.8.0.34 1
224.0.0.0 240.0.0.0 10.8.0.34 10.8.0.34 30
224.0.0.0 240.0.0.0 10.220.22.11 10.220.22.11 1
255.255.255.255 255.255.255.255 10.8.0.34 10.8.0.34 1
255.255.255.255 255.255.255.255 10.8.0.34 2 1
255.255.255.255 255.255.255.255 10.8.0.34 3 1
255.255.255.255 255.255.255.255 10.220.22.11 10.220.22.11 1
Passerelle par défaut : 10.220.22.11

Itinéraires persistants :
Aucun[/code]

Tu n’hésite pas à me demander si tu veux plus d’informations.

Petit up

UP