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Yes, but with some important exceptions:. It will make a best-effort to keep the tunnel active during pause, resume, and reconnect states to prevent packet leakage to the internet. Every 30 seconds, the computation is repeated and a new 6 digit code results. And at least one fixed global IP address is required on the network. Also, makes sure you are not using EC certificates as they are not yet supported. You can download it from https:

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Note that only autologin profiles i. A fix is expected in iOS 7. IPv6 tunnel routes may not be added to the routing table on iOS 7. For example, from the server: Note that these directives are currently only supported in the main profile, outside of blocks. Also note that proxy settings in the Settings app under OpenVPN always have priority over proxy directives given in the profile. This could potentially cause connection failures where the connect slider control would move into the ON position, the credentials fields would be cleared, but no connection would occur, or the connection slider would freeze in the OFF position.

It is provided only for compatibility with legacy systems. This may fix an issue where the following error is seen in the log: Previously we would raise an exception in this case.

The connection would fail if the server cannot meet this requirement. This behavior is somewhat different by design to 2. Note that this solution is still not ideal because the iOS keychain appears unable to import a PKCS 12 file as a bundle. So for this fix to be effective, each of the root and intermediate certs in the PKCS 12 file must be manually extracted and separately imported as. This feature allows proxy options to be set for Safari and possibly other apps as well for the duration of the VPN session.

These options can be placed directly in the profile, i. Updated PolarSSL to 1. Implemented "tls-remote", "route-nopull", "remote-random", "cipher none", and "auth none" directives. Support DNS names that resolve to multiple addresses by trying each address in sequence. At Apple's request, require one-time user confirmation before starting initial VPN connection.

Log invalid server-pushed routes or dhcp-options but don't disconnect. As device moves between WiFi and cellular networks, proactively reconnect. Raise an error when unsupported modes are used, such as static key mode. Support "tcp-client" usage such as this: Added "Reconnect on wakeup" preference on by default. The "key-direction" default has been changed to "bidirectional" for compatibility with OpenVPN 2. The solution is to explicitly declare key-direction in VPN-on-Demand profiles if the OpenVPN configuration file they are derived from declares it as well.

Fixed bug where pushed ifconfig subnet was not routing into the tunnel. When split-tunnel VPN configuration is used i. Fixed bug where app would crash on startup if device keychain had certificate with nil subjectSummary. Fixed issue where "reneg-sec 0" was causing an infinite reconnect loop.

Don't add IPv4 or v6 routes if the ifconfig for the particular IP protocol is absent. This effectively excludes the route from the tunnel. Allow clients to connect without a client certificate or key, if the server allows it, and if the client profile contains the following directive: Fixed an issue that prevented an External Certificate profile from also being an Autologin profile.

As of Access Server 2. Since the OpenVPN programs used work with a single encryption scheme, meaning that clients and server must all agree to use the same encryption cipher, it is not possible to alter this from one side without affecting connectivity.

If you change the cipher on an existing installation of Access Server, be prepared to reprovision or reinstall your already installed clients, so that they are updated correctly with instructions to use the new cipher, or they may simple be unable to connect. There is no automatic provisioning solution to automate this included in Access Server or the Connect Client. Those are updated automatically with the new cipher settings.

As of Access Server version 2. If you install a fresh Access Server 2. This way, we can maintain backward compatibility. The following information is valid only on Access Server 2.

And of course the ciphers used must be one of the allowed type and must be the same on server and client side. But it can also be controlled through the command line with a specific configuration key. By default, this value is set to minutes 6 hours. Session expiration will only be tested for during TLS renegotiation which occurs automatically at the specified schedule with this setting or when the connection is disrupted and reconnects.

So if you change the session token expiration , make sure to adjust this parameter as well, or else the connection may not stop at the exact threshold that the session token timeout is set to, which may lead to connections that last longer than what you set your session token expiration parameter to. It is important to note that there is also a parameter in the OpenVPN protocol no configuration key in Access Server that determines after how many bytes a key should be renegotiated, and that in the past, Blowfish was the encryption cipher used, and we use this additional bytes threshold parameter for vulnerability mitigation.

Unfortunately a flaw was found in Blowfish not so long ago that could be abused if enough data was gathered that used the same encryption key. To resolve this we have moved to AES as the default but still allow Blowfish on older installations and clients, but have set the key renegotiation byte threshold at around 60 megabytes on up-to-date OpenVPN client programs, to prevent any possible gathering of enough data to exploit that particular flaw in the Blowfish encryption cipher.

As a security precaution the Access Server automatically locks out user accounts temporarily when authentication attempts fail repeatedly when using a server-locked profile in Connect Client, or when using the web services directly. The lockout policy will not be triggered when a user-locked profile is used with an OpenVPN client program since this requires that the user already has a valid connection profile with certificates for his account, and to be in possession of such a file you would most likely already have the correct credentials anyways unless you stole the file from a user somehow - in which case the certificate should be revoked by an administrator , and the connection itself is also secured with the user's personal certificate and key so it is extremely unlikely to be intercepted in some way.

When repeated authentication failures occur through a server-locked profile in Connect Client, or via the web services directly, the user is temporarily banned from further login attempts. This is to prevent brute-forcing the password by endlessly trying different passwords. When this lockout is triggered on an account the user will receive a message like "LOCKOUT" or "user temporarily locked out due to multiple authentication failures".

By default the lockout is triggered when a wrong password is entered 3 times consecutively. When the lockout is triggered and you wait 15 minutes, the lockout will be lifted. Lockouts can also be lifted manually by the administrator. The lockout policy is configurable with the settings below. Set the number of authentication failures after which the user will be locked out default is Release the lockout on a user after the specified amount of seconds passes default is seconds, or 15 minutes:.

The lockout dictionary is used to keep track of all the hashes of wrong passwords that were entered by users recently. Unless you have thousands of users repeatedly entering incorrect passwords then the default value should be more than fine, and if you do have such a situation then you can increase the dictionary size. If the dictionary reaches its maximum size it will eventually be purged.

The consequence of this dictionary reaching its limits with thousands of users entering wrong passwords is that if the failed authentication attempts are spread far enough apart hours that the number of authentication failures can be higher than configured. If however the failed authentication attempts occur shortly after one another then the number of authentication failures per user will be adhered to just fine.

Generally you never need to adjust this value except in extreme circumstances which are very unlikely to ever occur. We recommend you do not change this value. As mentioned an exception to the lockout policy are authentication attempts made with a valid user-locked connection profile. Additionally the so-called "bootstrap" users, which are special administrative users of which by default only one exists, are also an exception to the lockout policy.

When Access Server is installed the initial administrative bootstrap user is called openvpn. This user account can always log in and does not adhere to the lockout policy. In our security recommendations to secure the openvpn administrative user account we specifically advise you to disable this special bootstrap user after initial setup. When you have run into the problem that your users have run into the automatic authentication lockout policy and are currently blocked, and you wish to unblock them, please follow the steps below.

It is important to note that at this time it is not possible to unlock a single specific user. Instead what we advise is that you set the automatic lockout reset period to 1 second, wait a moment so that all lockouts are reset, and then to set the lockout period back to whatever you had it set to before. The below lines will do this and assumes your lockout policy automatic reset period is supposed to be set back to the default 15 minutes seconds afterwards and restarts the Access Server to clear any locked sessions.

To explain the concept of TLS authentication in simpler terms, the idea here is to have a unique TLS key, a certificate, that is known and used by the server and its clients. A shared secret if you will, that will be used to digitally sign and verify packets in both directions. What this does is make it possible for the OpenVPN protocol to easily recognize if packets are truly VPN packets from a known VPN client, or if they are garbage packets from unknown sources.

Every OpenVPN packet by itself contains encrypted information inside of it, but on top of that, the packet itself is signed digitally. The other party receiving the packet can then check if the signature matches with the known shared TLS key, and if it does, can then handle it further. If it doesn't match, the packet is not from a known client and can be discarded. Aside from helping to filter away some attempts at denial of service attacks it also improves security by making other attacks impossible.

Some only have some menu options to provide a certificate, a key, and some encryption options for the OpenVPN tunnel, but no means to upload a configuration file or a TLS authentication key with the necessary instructions that the OpenVPN binary requires to implement TLS.

This leads to the odd situation that the OpenVPN binary in the product can support TLS authentication, but there is no way to configure it to use it. In these situations if connectivity is required it is possible to disable TLS authentication. Unfortunately this is an option that cannot be set per user account. This is a server-wide global setting. It is important to note that when switching a server from one mode to another, to enable or disable TLS authentication, requires that all the clients currently installed are reconfigured for the new setting.

OpenVPN Connect Client installations with a server-locked profile will automatically retrieve an updated connection profile when they next log on, but any clients that have a stored copy of a user-locked or auto-login type profile will need to be reconfigured or provided with a new connection profile in order to be able to connect again to a server that previously had a different TLS authentication setting.

The basic principle of how Google Authenticator works is reasonably simple but very secure. The server and the program, for example the Google Authenticator app for Android or iOS that generates your 6 digit codes, both need to know the current time and date. If they deviate too much then this can cause the codes to not correspond and thus not work.

Timezones are automatically adjusted for so this is not an issue unless you set the timezone wrong. With the correct current time and a shared secret 16 character random text string agreed upon by the server and the Google Authenticator application when you go through an initial enrollment procedure, a computation is done that results in a 6 digit code.

Every 30 seconds, the computation is repeated and a new 6 digit code results. When you make a connection using a correctly enrolled user account that requires Google Authenticator code, you will be asked for your user name, your password, and finally the Google Authenticator 6 digit code for that specific moment. It is only valid within a small window of time about 30 seconds. This way anyone peeking over your shoulder still won't be able to somehow use the gathered information to make a connection, because they don't have the shared secret key that generates the unique 6 digit codes every 30 seconds.

It is also important for security reasons to know that at no point a connection with Google's systems is made when enrolling a user, generating a shared secret key, or generating 6 digit one-time passwords. Everything happens within the Access Server itself without requiring outside contact with any servers or services, and within the application used to generate the 6 digit codes.

The specifications of the Google Authenticator system have been made public and the code is, to put it oversimplified, a matter of: To give users some leeway in entering the code, the Access Server will accept the current valid code, the one just before it, and the one just after it.

This creates a slightly larger window of time in which a user can enter the 6 digit code. More information on the conceptual and technical aspects of Google Authenticator can be found on this Google Authenticator WikiPedia page.

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