Probleme de connection openvpn

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Probleme de connection openvpn

Messagepar bradern » 17 Mai 2008 11:13

Bonjour à tous

Voila j'ai suivit le tutoriel suivant pour la mise en place d'un vpn
http://forum.hardware.fr/hfr/reseauxper ... et_2_1.htm

Le server fonctionne nickel enfin je pense ^^
Voila un extrait du fichier de log

Tue Jan 01 11:36:38 2002 192.168.1.21:32784 TLS: new session incoming connection from 192.168.1.21:32784
Tue Jan 01 11:36:47 2002 192.168.1.21:32783 TLS Error: TLS key negotiation failed to occur within 60 seconds (check your network connectivity)
Tue Jan 01 11:36:47 2002 192.168.1.21:32783 TLS Error: TLS handshake failed
Tue Jan 01 11:36:47 2002 192.168.1.21:32783 SIGUSR1[soft,tls-error] received, client-instance restarting
Tue Jan 01 11:36:50 2002 MULTI: multi_create_instance called
Tue Jan 01 11:36:50 2002 192.168.1.21:32785 Re-using SSL/TLS context
Tue Jan 01 11:36:50 2002 192.168.1.21:32785 LZO compression initialized
Tue Jan 01 11:36:50 2002 192.168.1.21:32785 Control Channel MTU parms [ L:1542 D:138 EF:38 EB:0 ET:0 EL:0 ]
Tue Jan 01 11:36:50 2002 192.168.1.21:32785 Data Channel MTU parms [ L:1542 D:1450 EF:42 EB:135 ET:0 EL:0 AF:3/1 ]
Tue Jan 01 11:36:50 2002 192.168.1.21:32785 Local Options hash (VER=V4): '530fdded'
Tue Jan 01 11:36:50 2002 192.168.1.21:32785 Expected Remote Options hash (VER=V4): '41690919'
Tue Jan 01 11:36:50 2002 192.168.1.21:32785 TLS: Initial packet from 192.168.1.21:32785, sid=de9cb2c9 3a30d036



Mais le client n'arrive pas à se connecter et me sort l'erreur suivante :

TCP/UDP : Incoming packet-rejected from 192.168.1.65:1194 expected adress : 79.80.xxx.xxx:1194 (allow this incoming source address/port by removing --remote or adding float)


Mon firewall est activé ou pas ça ne change rien :/.

Le truc étrange est le message du serveur au niveau du port 192.168.1.21:32785 alors que j'ai configurer le 1194, en même temps j'ai l'impression que ce numéro de port s'incremente à chaque nouvel essai


Si quelqu'un a une idée c'est pas de refus
Merci d'avance[/quote]
bradern
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Messagepar jdh » 17 Mai 2008 11:32

(A noter que le "beau dessin" en haut du lien donné est ASSEZ faux : le mieux serait que les réseaux privés de gauche et droite n'utilisent pas le même n° de réseau au sens ip !)


Pour aider, il faudrait d'autres infos :

- les adressages ip (complet avec masques, passerelle ...)
- les fichiers de conf du client et su serveur (avec adresse publique masquées).
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Messagepar bradern » 17 Mai 2008 11:52

Merci de prendre en compte mon probleme

Voila les fichiers de conf du serveur puis du client

le serveur


#################################################
# 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 tap" if you are ethernet bridging.
# 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 server.crt
key server.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 10.8.0.0 255.255.255.0

# 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 192.168.1.120 255.255.255.0 192.168.1.128 192.168.1.254

# 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 192.168.10.0 255.255.255.0"
;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 10.9.0.0 255.255.255.252
# 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
# the TUN/TAP interface to the internet in
# order for this to work properly).
# CAVEAT: May break client's network config if
# client's local DHCP server packets get routed
# through the tunnel. Solution: make sure
# client's local DHCP server is reachable via
# a more specific route than the default route
# of 0.0.0.0/0.0.0.0.
;push "redirect-gateway"

# Certain Windows-specific network settings
# can be pushed to clients, such as DNS
# or WINS server addresses. CAVEAT:
# http://openvpn.net/faq.html#dhcpcaveats
;push "dhcp-option DNS 10.8.0.1"
;push "dhcp-option WINS 10.8.0.1"

# 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 nobody

# 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


et maintenant le client


##############################################
# Sample client-side OpenVPN 2.0 config file #
# for connecting to multi-client server. #
# #
# This configuration can be used by multiple #
# clients, however each client should have #
# its own cert and key files. #
# #
# On Windows, you might want to rename this #
# file so it has a .ovpn extension #
##############################################

# Specify that we are a client and that we
# will be pulling certain config file directives
# from the server.
client

# Use the same setting as you are using on
# the server.
# 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,
# you may need to disable the firewall
# for the TAP adapter.
;dev-node MyTap

# Are we connecting to a TCP or
# UDP server? Use the same setting as
# on the server.
;proto tcp
proto udp

# The hostname/IP and port of the server.
# You can have multiple remote entries
# to load balance between the servers.
remote 79.80.177.169 1194
;remote my-server-2 1194

# Choose a random host from the remote
# list for load-balancing. Otherwise
# try hosts in the order specified.
;remote-random

# Keep trying indefinitely to resolve the
# host name of the OpenVPN server. Very useful
# on machines which are not permanently connected
# to the internet such as laptops.
resolv-retry infinite

# Most clients don't need to bind to
# a specific local port number.
nobind

# Downgrade privileges after initialization (non-Windows only)
;user nobody
;group nobody

# Try to preserve some state across restarts.
persist-key
persist-tun

# If you are connecting through an
# HTTP proxy to reach the actual OpenVPN
# server, put the proxy server/IP and
# port number here. See the man page
# if your proxy server requires
# authentication.
;http-proxy-retry # retry on connection failures
;http-proxy [proxy server] [proxy port #]

# Wireless networks often produce a lot
# of duplicate packets. Set this flag
# to silence duplicate packet warnings.
;mute-replay-warnings

# SSL/TLS parms.
# See the server config file for more
# description. It's best to use
# a separate .crt/.key file pair
# for each client. A single ca
# file can be used for all clients.
ca ca.crt
cert client1.crt
key client1.key

# Verify server certificate by checking
# that the certicate has the nsCertType
# field set to "server". This is an
# important precaution to protect against
# a potential attack discussed here:
# http://openvpn.net/howto.html#mitm
#
# To use this feature, you will need to generate
# your server certificates with the nsCertType
# field set to "server". The build-key-server
# script in the easy-rsa folder will do this.
ns-cert-type server

# If a tls-auth key is used on the server
# then every client must also have the key.
;tls-auth ta.key 1

# Select a cryptographic cipher.
# If the cipher option is used on the server
# then you must also specify it here.
;cipher x

# Enable compression on the VPN link.
# Don't enable this unless it is also
# enabled in the server config file.
comp-lzo

# Set log file verbosity.
verb 3

# Silence repeating messages
;mute 20
bradern
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Messagepar HaM » 17 Mai 2008 12:11

Salut,

A la vue de ceci : Incoming packet-rejected from 192.168.1.65:1194
Voici mon avis. Le problème vient de ton firewall (c'est quoi comme firewall ?) enfin du truc qui partage ta connexion internet (une box peut être ?). Il fait du masquerading dans les deux sens (très mauvais!)...
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Messagepar bradern » 17 Mai 2008 12:14

je suis en réseau local est mon firewall c'est Zone Alarm et qu'il soit activé ou desactivé c'est pareil :/
Petite précision mon routeur c'est une NeufBox NB4
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Messagepar HaM » 17 Mai 2008 12:18

bradern a écrit:je suis en réseau local est mon firewall c'est Zone Alarm et qu'il soit activé ou desactivé c'est pareil :/
Petite précision mon routeur c'est une NeufBox NB4


Ton firewall "local" ZoneAlarm n'est pas celui dont je parlais.

Ce que je vois c'est que ta box remplace l'IP source par la sienne. Normal quand tu envois un paquet depuis ton réseau local vers le net. Mais pas quand un paquet arrive du net (dans ce cas elle ne devrait changer que l'adresse de destination).

Enfin moi c'est le premier truc que je vois de flagrant.

Fait quelque tests en sniffant voir ce qui se passe ...
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Messagepar bradern » 17 Mai 2008 12:42

euh on utilise quoi pour snif stp
bradern
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Messagepar jdh » 17 Mai 2008 13:13

Moi j'aurais présenté le problème de la façon suivante :


* schéma réseau

PC portable sur Internet <-> Neufbox4 <-> PC Serveur


* Adressage ip et info sur les matériels :

PC Portable (sous Windows) : accès à Internet via un adsl
Neufbox4 : configuré en routeur : ip public 79.80.177.X, ip interne 192.168.1.1/255.255.255.0
PC serveur (sous ?) : adresse ip 192.168.1.21, serveur OpenVpn fournira des adresses 10.8.0.X


* routeur
La neufbox est configurée pour renvoyer le flux udp/1194 vers le serveur (192.168.1.21).


* fichier de conf serveur :

#------- conf serveur ----------
;local a.b.c.d
proto udp
port 1194
dev tun
;dev-node MyTap

ca ca.crt
cert server.crt
key server.key # This file should be kept secret
dh dh1024.pem

server 10.8.0.0 255.255.255.0

ifconfig-pool-persist ipp.txt

;push "route 192.168.10.0 255.255.255.0"
;push "redirect-gateway"
;push "dhcp-option DNS 10.8.0.1"
;push "dhcp-option WINS 10.8.0.1"

client-to-client

;duplicate-cn

keepalive 10 120
;tls-auth ta.key 0 # This file is secret
;cipher BF-CBC # Blowfish (default)
;cipher AES-128-CBC # AES
;cipher DES-EDE3-CBC # Triple-DES
comp-lzo
;max-clients 100
;user nobody
;group nobody

persist-key
persist-tun
status openvpn-status.log
;log openvpn.log
;log-append openvpn.log

verb 3
;mute 20
#------- conf serveur ----------


* fichier de conf client :

#------- conf client ----------
client

;dev tap
dev tun

;dev-node MyTap

proto udp

remote 79.80.177.X 1194
;remote-random

resolv-retry infinite

nobind

;user nobody
;group nobody

persist-key
persist-tun

;http-proxy-retry # retry on connection failures
;http-proxy [proxy server] [proxy port #]

;mute-replay-warnings

ca ca.crt
cert client1.crt
key client1.key

ns-cert-type server

;tls-auth ta.key 1
;cipher x
comp-lzo

verb 3
;mute 20
#------- conf client ----------



Il y a beaucoup de choses à préciser encore ... Il faut comprendre qu'il est nécessaire de fournir des infos, même celles qui semblent inutiles ...

Je donnerais mes fichier de config dans un fil suivant
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Messagepar bradern » 17 Mai 2008 13:39

oki je viens de verifier j'ai la meme configuration que toi
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Messagepar jdh » 17 Mai 2008 13:59

Ce N'est PAS ma config !!!!

C'est TA config à partir des éléments indiqués et ma réflexion.

Il est IMPORTANT que TOI, tu décrives TA config autour d'une trame que je propose et qui tend à être suffisante (à défaut d'être complète).

Donc, décris, complètes et encore complètes ...


(PS : mes config soit parfois plus complexes mais elles ont plusieurs points communs : elles fonctionnent, elles se ressemblent, et je ne l'ai pas réussies sans avoir vérifier, tester à donf !)
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Messagepar bradern » 17 Mai 2008 14:06

dsl là je suis vraiment à l'Est est c'est peu de le dire
j'ai beau verifier mes configs et lire les different tuto je ne vois pas ce qui ne va pas?


Certains site dise que la neufbox NB4 empeche OpenVPN de fonctionne
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Messagepar jdh » 17 Mai 2008 14:14

Je suis obligé de partir ...

Un point critique est évidemment que le Neufbox, comme n'importe quel routeur, renvoie bien le trafic udp/1194 vers le serveur. Et ce qui va avec, c'est que la config du client accède bien à l'adresse ip publique, ce qui me parait ok.

Deuxième point clé, les fichiers de conf OpenVpn.

Troisième point, les firewalls du serveur et du client doivent autoriser le trafic udp/1194 selon le sens idoine.


Je vais essayer de retrouver les 2 fichiers de conf serveur/client qui vont bien
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Messagepar jdh » 18 Mai 2008 20:35

Une config d'un de mes réseaux :

- Le réseau interne est 192.168.2.0/255.255.255.0.
- L'adressage fourni sera dans 192.168.5.0/255.255.255.0.
- Il y a un serveur Linux (192.168.2.14) fonctionnant avec Samba (wins) et fournissant un dns local (xxxx.com).
- L'adresse extérieure est xxxx.dyndns.com.
- Le certificat client est xxxx.crt + xxxx.key.


Mon fichier de conf serveur (fw) :
#--------------------------------------------
proto udp
port 1194
dev tun

ca ca.crt
cert fw.crt
key fw.key
dh dh1024.pem

server 192.168.5.0 255.255.255.0
ifconfig-pool-persist ipp.txt
push "route 192.168.2.0 255.255.255.0"

push "dhcp-option DNS 192.168.2.14"
push "dhcp-option WINS 192.168.2.14"
push "dhcp-option DOMAIN xxxx.com"

keepalive 10 120
comp-lzo

user openvpn
group openvpn

persist-key
persist-tun

verb 4
#--------------------------------------------


Mon fichier de conf client :
#--------------------------------------------
client

port 1194
proto udp
dev tun

remote xxxx.dyndns.com
resolv-retry infinite
nobind

persist-tun
persist-key

ca ca.crt
cert xxxx.crt
key xxxx.key

ns-cert-type server

comp-lzo

verb 4
#--------------------------------------------



En écrivant ceci, je constate que ta config n'est pas très éloignée. Il faut donc veiller à vérifier que la redirection au niveau de la Neufbox est correctement configurée, et que les config firewall sont adaptées.
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