Openvpn / Sslh / Nginx

[Terrano]

Hello,

J'essaie de configurer OpenVPN pour me connecter en sécurisé par le port 443.

J'ai suivi le tuto suivant : http://www.funnyplace.fr/securiser-acces-nas-synology-openvpn/

Or, ce tuto ne tient pas compte du fait que j'ai SSLH et NGINX d'installé.

Premiere question :

Dois je faire la solution 1 :

BOX (port 443) -> OpenVPN (port 1194) -> SSLH (port 5443) -> (NGINX (port 6443 / SSH (port 22))

ou plutot la solution 2 :

BOX (port 443) -> SSLH (port 5443) -> (OpenVPN (port 1194) / Nginx (port 6443) / SSH(port 22))

Actuellement, BOX (port 443) -> SSLH (port 5443) -> (NGINX (port 6443 / SSH (port 22)) fonctionne parfaitement.

Deuxième question :

Est-ce que les fichiers suivants sont corrects ?

openvpn.conf

push "route 10.8.0.0 255.255.255.0"
push "route 192.168.0.0 255.255.255.0"
dev tun
port 1194
port-share 127.0.0.1 5443
proto tcp
management 127.0.0.1 1195

server 10.8.0.0 255.255.255.0

tls-auth /var/packages/VPNCenter/target/etc/openvpn/keys/ta.key 0
dh /var/packages/VPNCenter/target/etc/openvpn/keys/dh2048.pem
ca /var/packages/VPNCenter/target/etc/openvpn/keys/ca.crt
cert /var/packages/VPNCenter/target/etc/openvpn/keys/server.crt
key /var/packages/VPNCenter/target/etc/openvpn/keys/server.key

max-clients 5

comp-lzo

persist-tun
persist-key

verb 3

#log-append /var/log/openvpn.log

keepalive 10 60
reneg-sec 3600

plugin /var/packages/VPNCenter/target/lib/radiusplugin.so /var/packages/VPNCenter/target/etc/openvpn/radiusplugin.cnf
client-cert-not-required
username-as-common-name
duplicate-cn
cipher AES-256-CBC
status /tmp/ovpn_status_2_result 30
status-version 2

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 FilesOpenVPNconfigfoo.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 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 dh2048.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 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 192.168.10.0 255.255.255.0"
;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
# 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
cipher AES-256-CBC

# 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 FilesOpenVPNlog" 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

Je n'arrive pas à me connecter avec le mobile, j'obtient le message suivant :

Connecting to 'mondomaine.fr:443' (monip) via TCPv4
TCP recv EOF
Transport Error: Transport error on 'mondomaine.fr': NETWORK_EOF_ERROR [ERR]
Client terminated

En fait, ça n'arrive jamais à OpenVPN sachant qu'actuellement je teste la solution 2.

Vous pouvez m'aider ?

PS : tous les certificats sont ok car ça marche très bien sur un PC en local.

[Terrano]

Alors, j'ai testé différentes configurations entre mon iphone et mon nas pour passer par openVPN et étrangement, une seule solution passe : Port 1194 en UDP

J'ai essayé ceci :

Port 1194 en TCP directement vers openVPN : KO

Port 443 en UDP en passant par SSLH : KO

Port 443 en TCP en passant par SSLH : KO

C'est pas bien grave ne souhaitant par un openVPN forcément sur le 443 mais je déteste ne pas trouver d'où vient le problème.

Quelqu'un a-t-il déjà essayé d'utiliser SSLH pour se connecter en TCP sur le port 443 à OpenVPN ?

[chiptuned]

Salut, j'ai le même souci que toi, j'ai donc cherché des topics de forums et je suis tombé sur le tien.

Cependant, en trifouillant avant de poster mon message, j'ai ceci :

Port 1194 en UDP directement vers openVPN : OK

Port 1194 en TCP directement vers openVPN : OK

Port 443 en UDP en passant par SSLH : KO

Port 443 en TCP en passant par SSLH : OK

Du coup ça fonctionne niquel pour moi en tcp. Pour ce faire j'ai édité /etc/openvpn pour du tcp, et évidemment mon fichier client ovpn pour que ça suive.

Je suppose également que ta config de sslh est bonne, du coup je me demande si le multiplexage d'openvpn via sslh fonctionne uniquement en tcp.
Malheuresement je ne dispose pas assez de connaissances pour le vérifier. Je vais voir si je peux demander au dev, ou si t'as une idée.

Je suppose que tu as avancé sur ce pb depuis ce temps (désolé pour le bump). Je poste ceci au cas où.

[Fenrir]

Pas utilisé depuis plusieurs années, mais à l'époque, SSLH ne fonctionnait qu'avec certains protocole (ceux qu'il sait reconnaitre) et uniquement sur TCP.

[chiptuned]

Repo Github : https://github.com/yrutschle/sslh

OpenVPN support

OpenVPN clients connecting to OpenVPN running with -port-share reportedly take more than one second between the time the TCP connexion is established and the time they send the first data packet. This results in sslh with default settings timing out and assuming an SSH connexion. To support OpenVPN connexions reliably, it is necessary to increase sslh's timeout to 5 seconds.

Instead of using OpenVPN's port sharing, it is more reliable to use sslh's --openvpn option to get sslh to do the port sharing.

Ici le dev implique l'utilisation du TCP. Tu dois avoir raison Fenrir. De plus, autant bien lire les indications, comme toujours! C'est résolu pour ma part. En espérant que ça aide l'auteur.

[Terrano]

Exact, ça fonctionne parfaitement sur TCP, ce qui posait le problème, c'était les certificats en fait.

Avec la perte de mes disques et la reconstruction du serveur, j'ai pu revoir l'installation et là, tout fonctionne nickel avec mes certificats