Transport Encryption

Bareos uses TLS (Transport Layer Security) to provide secure network transport. For data encryption in contrast, please see the Data Encryption chapter. The initial Bacula encryption implementation has been written by Landon Fuller.

With Version >= 18.2.4 the TLS code has been enhanced by the TLS-PSK (Pre Shared Keys) feature which allows the daemons to setup an encrypted connection directly without using certificates. The library used for TLS is openSSL.

TLS Configuration Directives

Additional configuration directives have been added to all the daemons (Director, File daemon, and Storage daemon) as well as the various different Console programs. These directives are defined as follows:

TLS Enable (Dir->Director)

Enable TLS support. This is by default enabled. If no certificates are configured PSK (Pre Shared Keys) ciphers will be used. If the other side does not support TLS, or cleartext is configured the connection will be aborted. However, for downward compatibility with clients before Bareos-18.2 the daemons can omit transport encryption and cleartext will be sent.

TLS Require (Dir->Director)

Require TLS connection, for downward compatibility. This is by default disabled. However, if TlsRequire=yes, clients with a version before Bareos-18.2 will be denied if configured to use cleartext.

TLS Certificate (Dir->Director)

The full path and filename of a PEM encoded TLS certificate. It can be used as either a client or server certificate. It is used because PEM files are base64 encoded and hence ASCII text based rather than binary. They may also contain encrypted information.

TLS Key (Dir->Director)

The full path and filename of a PEM encoded TLS private key. It must correspond to the certificate specified in the TLS Certificate configuration directive.

TLS Verify Peer (Dir->Director)

Request and verify the peers certificate.

In server context, unless the TLS Allowed CN configuration directive is specified, any client certificate signed by a known-CA will be accepted.

In client context, the server certificate CommonName attribute is checked against the Address and TLS Allowed CN configuration directives.

TLS Allowed CN (Dir->Director)

Common name attribute of allowed peer certificates. If TLS Verify Peer=yes, all connection request certificates will be checked against this list.

This directive may be specified more than once as all parameters will we concatenated.

TLS CA Certificate File (Dir->Director)

The full path and filename specifying a PEM encoded TLS CA certificate(s). Multiple certificates are permitted in the file.

In a client context, one of TLS CA Certificate File or TLS CA Certificate Dir is required.

In a server context, it is only required if TLS Verify Peer is used.

TLS CA Certificate Dir (Dir->Director)

Full path to TLS CA certificate directory. In the current implementation, certificates must be stored PEM encoded with OpenSSL-compatible hashes, which is the subject name’s hash and an extension of .0.

In a client context, one of TLS CA Certificate File or TLS CA Certificate Dir is required.

In a server context, it is only required if TLS Verify Peer is used.

TLS DH File (Dir->Director)

Path to PEM encoded Diffie-Hellman parameter file. If this directive is specified, DH key exchange will be used for the ephemeral keying, allowing for forward secrecy of communications. DH key exchange adds an additional level of security because the key used for encryption/decryption by the server and the client is computed on each end and thus is never passed over the network if Diffie-Hellman key exchange is used. Even if DH key exchange is not used, the encryption/decryption key is always passed encrypted. This directive is only valid within a server context.

To generate the parameter file, you may use openssl:

create DH key

openssl dhparam -out dh1024.pem -5 1024

Getting TLS Certificates

To get a trusted certificate (CA or Certificate Authority signed certificate), you will either need to purchase certificates signed by a commercial CA or become a CA yourself, and thus you can sign all your own certificates.

Bareos is known to work well with RSA certificates.

You can use programs like xca or TinyCA to easily manage your own CA with a Graphical User Interface.

Example TLS Configuration Files

Examples of the TLS portions of the configuration files are listed below.

Bareos Director

bareos-dir.d/director/bareos-dir.conf

Director {                            # define myself
    Name = bareos-dir
    ...
    TLS Enable = yes     #yes by default
    TLS CA Certificate File = /etc/bareos/tls/ca.pem
    # This is a server certificate, used for incoming
    # (console) connections.
    TLS Certificate = /etc/bareos/tls/bareos-dir.example.com-cert.pem
    TLS Key = /etc/bareos/tls/bareos-dir.example.com-key.pem
    TLS Verify Peer = yes
    TLS Allowed CN = "bareos@backup1.example.com"
    TLS Allowed CN = "administrator@example.com"
}

bareos-dir.d/storage/File.conf

Storage {
    Name = File
    Address = bareos-sd1.example.com
    ...
    TLS Enable = yes     #yes by default
    TLS CA Certificate File = /etc/bareos/tls/ca.pem
    # This is a client certificate, used by the director to
    # connect to the storage daemon
    TLS Certificate = /etc/bareos/tls/bareos-dir.example.com-cert.pem
    TLS Key = /etc/bareos/tls/bareos-dir.example.com-key.pem
    TLS Allowed CN = bareos-sd1.example.com
}

bareos-dir.d/client/client1-fd.conf

Client {
    Name = client1-fd
    Address = client1.example.com
    ...
    TLS Enable = yes     #yes by default
    TLS CA Certificate File = /etc/bareos/tls/ca.pem
    TLS Certificate = "/etc/bareos/tls/bareos-dir.example.com-cert.pem"
    TLS Key = "/etc/bareos/tls/bareos-dir.example.com-key.pem"
    TLS Allowed CN = client1.example.com
}

Bareos Storage Daemon

bareos-sd.d/storage/bareos-sd1.conf

Storage {
    Name = bareos-sd1
    ...
    # These TLS configuration options are used for incoming
    # file daemon connections. Director TLS settings are handled
    # in Director resources.
    TLS Enable = yes     #yes by default
    TLS CA Certificate File = /etc/bareos/tls/ca.pem
    # This is a server certificate. It is used by connecting
    # file daemons to verify the authenticity of this storage daemon
    TLS Certificate = /etc/bareos/tls/bareos-sd1.example.com-cert.pem
    TLS Key = /etc/bareos/tls/bareos-sd1.example.com-key.pem
    # Peer verification must be disabled,
    # or all file daemon CNs must be listed in "TLS Allowed CN".
    # Peer validity is verified by the storage connection cookie
    # provided to the File Daemon by the Director.
    TLS Verify Peer = no
}

bareos-sd.d/director/bareos-dir.conf

Director {
    Name = bareos-dir
    ...
    TLS Enable = yes     #yes by default
    TLS CA Certificate File = /etc/bareos/tls/ca.pem
    # This is a server certificate. It is used by the connecting
    # director to verify the authenticity of this storage daemon
    TLS Certificate = /etc/bareos/tls/bareos-sd1.example.com-cert.pem
    TLS Key = /etc/bareos/tls/bareos-sd1.example.com-key.pem
    # Require the connecting director to provide a certificate
    # with the matching CN.
    TLS Verify Peer = yes
    TLS Allowed CN = "bareos-dir.example.com"
}

Bareos File Daemon

bareos-fd.d/client/myself.conf

Client {
    Name = client1-fd
    ...
    # you need these TLS entries so the SD and FD can
    # communicate
    TLS Enable = yes     #yes by default

    TLS CA Certificate File = /etc/bareos/tls/ca.pem
    TLS Certificate = /etc/bareos/tls/client1.example.com-cert.pem
    TLS Key = /etc/bareos/tls/client1.example.com-key.pem

    TLS Allowed CN = bareos-sd1.example.com
}

bareos-fd.d/director/bareos-dir.conf

Director {
    Name = bareos-dir
    ...
    TLS Enable = yes     #yes by default
    TLS CA Certificate File = /etc/bareos/tls/ca.pem
    # This is a server certificate. It is used by connecting
    # directors to verify the authenticity of this file daemon
    TLS Certificate = /etc/bareos/tls/client11.example.com-cert.pem
    TLS Key = /etc/bareos/tls/client1.example.com-key.pem
    TLS Verify Peer = yes
    # Allow only the Director to connect
    TLS Allowed CN = "bareos-dir.example.com"
}

Compatibility with Bareos File Daemon

Bareos File Daemon connection handshake probing

As from Bareos 18.2 all components by default establish a secure connection with encryption first, followed by the proprietary Bareos protocol. This is accomplished using TLS-PSK. Older components of Bareos than version 18.2 start a connection with a cleartext handshake without encryption.

For downward compatibility Bareos Director Daemons and Bareos Storage Daemons are able to connect to Bareos File Daemons older than version 18.2. In this case Director and Storage switch to the old protocol.

There are two connection modes of a File Daemon, active and passive. In contrast to a connection from an active Bareos File Daemon, the protocol version of a passive File Daemon has to be probed by the Director Daemon initially when a job is initiated. This information is stored in the configuration and immediately submitted to the Storage Daemon when the job is started.

The following sequence is used to figure out the right protocol version and to submit this information to the attached Bareos Storage Daemon:

$hide footbox Actor user participant "ConfigurationParser\nclass" as Config << C,#EEEEEE >> participant "Some methods in\ndirectordaemon namespace" as Dir << N,#EEEEEE >> participant "Client methods in\n directordaemon namespace" as F << N,#EEEEEE >> participant "Client methods in\n filedaemon namespace" as FC << N,#EEEEEE >> == Config Initialisation == user -> Config: reload config activate Config Config -> Config: ParseConfigFile() Config -> Dir: ConfigReadyCallback() activate Dir Dir -> Config: ResetAllClientConnectionHandshakeModes Dir <-- Config: All handshake modes reset to\nClientConnectionHandshakeMode::kUndefined Config <-- Dir: ConfigReadyCallback() done deactivate Dir user <-- Config: config reloaded ... try to connect to a client ... == Client Connection to old unknown client == user -> Dir: run some client command activate Dir Dir -> F: ConnectToFileDaemon() activate F note right of F: Possible modes:\nkTlsFirst (try TLS immediately),\nkCleartextFirst (old cleartext handshake) F ->> FC: Try to connect to Filedaemon with immediate TLS\nconnection mode (kTlsFirst) F ->> FC: If immediate TLS fails try cleartext handshake mode\n(kCleartextFirst, this will happen with old clients before 18.2) F <- FC: Connection established Config <- F: Save successful mode into configuration of client Dir <-- F: ConnectToFileDaemon() done ... do something with client ... FC <--> F: close client connection Dir <-- F: user <-- Dir : finished some client command deactivate F deactivate Dir ... connect to the same filedaemon again ... == Client Connection to a known client == user -> Dir: run some client command activate Dir Dir -> F: ConnectToFileDaemon() activate F Config -> F: Load successful mode from configuration of client F -> FC: Connect to Filedaemon with saved connection mode from config F <- FC: Connection established without waiting or probing Dir <-- F: ConnectToFileDaemon() done ... do something with client ... FC <--> F: close client connection Dir <-- F: user <-- Dir : finished some client command deactivate F deactivate Dir deactivate Config$

Sequence diagram of a Bareos File Daemon connection

Bareos File Daemon 18.2 with Bareos before 18.2

Bareos File Daemon >= 18.2 can be used on a Bareos system before Bareos-18.2.

The older Bareos Director and Bareos Storage Daemon connect to Bareos File Daemon using the cleartext Bareos handshake before they can switch to TLS. If you want transport encryption then only TLS with certificates can be used. TLS-PSK is not possible with Bareos Director and Bareos Storage Daemon before Bareos-18.2.

However, it is also possible to disable transport encryption and use cleartext transport using the following configuration changes:

Bareos Director configuration

/etc/bareos/bareos-dir.d/client/bareos-fd.conf

Client {
  ...
  TlsEnable = no
  TlsRequire = no
  ...
}

/etc/bareos/bareos-dir.d/storage/bareos-sd.conf

Storage {
  ...
  TlsEnable = no
  TlsRequire = no
  ...
}

Bareos Storage Daemon configuration

/etc/bareos/bareos-sd.d/storage/bareos-sd.conf

Storage {
  ...
  TlsEnable = no
  TlsRequire = no
  ...
}

Bareos File Daemon configuration before 18.2

/etc/bareos/bareos-fd.d/client/bareos-fd.conf

Client {
  ...
  TlsEnable = no
  TlsRequire = no
  ...
}

/etc/bareos/bareos-fd.d/director/bareos-dir.conf

Director {
  ...
  TlsEnable = no
  TlsRequire = no
  ...
}

Bareos File Daemon before 18.2 with Bareos 18.2

Bareos File Daemon before 18.2 can be used on a Bareos system 18.2 onwards.

The newer Bareos Director and Bareos Storage Daemon connect to Bareos File Daemon using the cleartext Bareos handshake before they switch to TLS. If you want transport encryption only TLS with certificates can be used, not PSK as it is possible with Bareos 18.2.

However, it is also possible to disable transport encryption and use cleartext transport using the following configuration changes:

Bareos File Daemon configuration

/etc/bareos/bareos-fd.d/client/bareos-fd.conf

Client {
  ...
  TlsEnable = no
  TlsRequire = no
  ...
}

/etc/bareos/bareos-fd.d/director/bareos-dir.conf

Director {
  ...
  TlsEnable = no
  TlsRequire = no
  ...
}

Bareos Webui

Transport encryption between Bareos Webui and a Bareos Director can be configured on a per restricted named console basis.

TLS-PSK is not available between the Bareos WebUI and the Bareos Director, in the following you will set up TLS with certificates.

Please check the following configuration examples. A complete table of the directives in the directors.ini file see: Overview of the settings in the Bareos Webui directors.ini file

Note

For Bareos Webui the certificate file given by configuration parameter cert_file in directors.ini has to contain the certificate and the key in PEM encoding.

Configuration example

Changed in version 18.2.

Warning

In Bareos version 18.2, the global certificates configured in the director resource in the director configuration need to be used. Before, the certificates configured in the console resource of the director configuration were used.

/etc/bareos-webui/directors.ini

;------------------------------------------------------------------------------
; Section backup.example.com
;------------------------------------------------------------------------------
[backup.example.com]
enabled = "yes"
diraddress = "backup.example.com"
dirport = 9101
;catalog = "MyCatalog"
tls_verify_peer = false
server_can_do_tls = true
server_requires_tls = false
client_can_do_tls = true
client_requires_tls = true
ca_file = "/etc/bareos-webui/tls/ca.crt"
cert_file = "/etc/bareos-webui/tls/client.pem"
;cert_file_passphrase = ""
;allowed_cns = ""

/etc/bareos/bareos-dir.d/director/bareos-dir.conf

Director {
   Name = bareos-dir
   QueryFile = "/usr/lib/bareos/scripts/query.sql"
   Maximum Concurrent Jobs = 10
   Password = "654321"
   Messages = Daemon
   Auditing = yes

   # Enable the Heartbeat if you experience connection losses
   # (eg. because of your router or firewall configuration).
   # Additionally the Heartbeat can be enabled in bareos-sd and bareos-fd.
   #
   # Heartbeat Interval = 1 min

   # remove comment from "Plugin Directory" to load plugins from specified directory.
   # if "Plugin Names" is defined, only the specified plugins will be loaded,
   # otherwise all director plugins (*-dir.so) from the "Plugin Directory".
   #
   # Plugin Directory = "/usr/lib64/bareos/plugins"
   # Plugin Names = ""

   TLS Enable = yes
   TLS Require = no
   TLS Verify Peer = no
   TLS CA Certificate File = /etc/bareos/tls/ca.crt
   TLS Certificate = /etc/bareos/tls/server.crt
   TLS Key = /etc/bareos/tls/server.pem
}

Overview of the settings in the Bareos Webui `directors.ini` file

TLS settings for Bareos Webui
Directive	Type	Default value	Remark	Description
tls_verify_peer	boolean	false	Optional	TLS verif peer
server_can_do_tls	boolean	false	Required	Server (Bareos Director) can do TLS
server_requires_tls	boolean	false	Required	Server (Bareos Director) requires TLS
client_can_do_tls	boolean	false	Required	Client can do TLS
client_requires_tls	boolean	false	Required	Client requires TLS
ca_file	string		Required	Certificate authority file
cert_file	string		Required	Path to the certificate file which needs to contain the client certificate and the key in PEM encoding
cert_file_passphrase	string		Optional	Passphrase to unlock the certificate file given by cert_file
allowed_cns	string		Optional	Allowed common names

TLS Configuration Reference

To be able to communicate via TLS, TLS needs to be configured on both sides. In Bareos certain directives are used to set up TLS.

The following table explains the location of the relevant TLS configuration directives for all possible Bareos TCP connections. Each resource is referred to as <component>-<resource> to identify the exact configuration location. Refer to chapter Customizing the Configuration for more details about configuration.

In Bareos Version 18.2 the relevant resources for some connections had to be changed. Affected directives are marked with the applicable version and the respective resource is written in bold letters.

Remark: TLS-PSK is not available on Bareos components before Version 18.2.

TLS Configuration Reference

Config Directive / Connection No. [1]

TCP-Client

TCP-Server

1

Default Console

→

Director

Name [2]

*UserAgent* [4]

*UserAgent* [4]

Password [3]

Console-Director

Director-Director

Certificate directives

Console-Director

Director-Director

Tls Enable / Tls Require

Console-Director

Director-Director

2

Named Console

→

Director

Name [2]

Console-Console

Director-Console

Password [3]

Console-Console

Director-Console

Certificate directives [5], Version 17.2:

Console-Console

Director-Console

Certificate directives [5], Version 18.2:

Console-Console

Director-Director

Tls Enable / Tls Require

Console-Console

Director-Console

3

Director

→

File Daemon

Name, Version 17.2:

Director-Client

Client-Director

Name [2], Version 18.2:

Director-Director

Client-Director

Password [3]

Director-Client

Client-Director

Certificate directives [5], Version 17.2:

Director-Client

Client-Director

Certificate directives [5], Version 18.2:

Director-Client

Client-Client

Tls Enable / Tls Require

Director-Client

Client-Director

4

File Daemon

→

Director

Name, Version 17.2:

Client-Director

Director-Client

Name [2], Version 18.2:

Client-Client

Director-Client

Password [3]

Client-Director

Director-Client

Certificate directives [5], Version 17.2:

Client-Director

Director-Client

Certificate directives [5], Version 18.2:

Client-Director

Director-Director

Tls Enable / Tls Require

Client-Director

Director-Client

5a, 5b

Director

→

Storage Daemon

Name, Version 17.2:

Director-Storage

Storage-Director

Name [2], Version 18.2:

Director-Director

Storage-Director

Password [3]

Director-Storage

Storage-Director

Certificate directives [5], Version 17.2:

Director-Storage

Storage-Director

Certificate directives [5], Version 18.2:

Director-Storage

Storage-Storage

Tls Enable / Tls Require

Director-Storage

Storage-Director

6

File Daemon

→

Storage Daemon

Name, Version 17.2:

not defined

not defined

Name [2], Version 18.2:

job name

job name

Password [3]

job session key

job session key

Certificate directives [5], Version 17.2:

Director-Storage

Storage-Director

Certificate directives [5], Version 18.2:

Director-Storage

Storage-Storage

Tls Enable / Tls Require

Director-Storage

Storage-Director

7

Storage Daemon

→

File Daemon

Name, Version 17.2:

not defined

not defined

Name [2], Version 18.2:

job name

job name

Password [3]

job session key

job session key

Certificate directives [5], Version 17.2:

Certificate directives [5], Version 18.2:

Storage-Storage

Client-Client

Tls Enable / Tls Require

Director-Client

Client-Client

8

Storage Daemon

→

Storage Daemon

Name, Version 17.2:

not defined

not defined

Name [2], Version 18.2:

job name

job name

Password [3]

job session key

job session key

Certificate directives [5]

Storage-Storage

Storage-Storage

Tls Enable / Tls Require

Director-W Storage

Director-W Storage

9

Traymon

→

Director

Name [2]

Traymon-Traymon

Director-Console

Password [3]

Traymon-Traymon

Director-Console

Certificate directives [5]

Traymon-Director

Director-Director

Tls Enable / Tls Require

Traymon-Director

Director-Console

10

Traymon

→

FD

Name [2]

Traymon-Traymon

Client-Director

Password [3]

Traymon-Client

Client-Director

Certificate directives [5]

Traymon-Client

Client-Client

Tls Enable / Tls Require

Traymon-Client

Client-Director

11

Traymon

→

SD

Name [2]

Traymon-Traymon

Storage-Director

Password [3]

Traymon-Storage

Storage-Director

Certificate directives [5]

Traymon-Storage

Storage-Storage

Tls Enable / Tls Require

Traymon-Storage

Storage-Director

Footnotes

Enabling Kernel TLS

Kernel TLS is a feature of some operating systems in which the application may pass data directly to the kernel, so that it performs the necessary encryption in kernel space.

Warning

If Kernel TLS is used then the data is written unencrypted to the socket.

This allows the kernel to offload this work to dedicated hardware to speed up the connection.

You may set the following options to Yes so that the respective daemon announces to the operating system that it wants to make use of Kernel TLS.

Enable kTLS (Dir->Director) Enable kTLS (Fd->Client) Enable kTLS (Sd->Storage)

Note

In the end the SSL implementation and the operating system itself will decide whether Kernel TLS will be used or not. Bareos cannot influence this decision directly.

To make it more likely that Kernel TLS is used, you may consult your operating system vendors manual to see which TLS ciphers it supports and configure bareos to use those.

Warning

Some SSL implementations do not correctly report whether Kernel TLS is used or not. In that case Bareos may send data completely unencrypted! Make sure to study the respective manuals.

If EnableKtls was set to Yes then Bareos will emit a debug message saying whether it thinks that Kernel TLS is enabled or not.

Note

On some operating systems you have to prepare Kernel TLS before bareos can take advantage of it. For example on Linux you have to load the tls kernel module.

connecting a console with Kernel TLS enabled

bin/bconsole -d150
[...]
bconsole (100): lib/tls_openssl_private.cc:58-0 Construct TlsOpenSslPrivate
bconsole (100): lib/tls_openssl_private.cc:614-0 Set tcp filedescriptor: <3>
bconsole (100): lib/tls_openssl_private.cc:632-0 Set protocol:       <>
bconsole (100): lib/tls_openssl_private.cc:554-0 Set ca_certfile:    <>
bconsole (100): lib/tls_openssl_private.cc:560-0 Set ca_certdir:     <>
bconsole (100): lib/tls_openssl_private.cc:566-0 Set crlfile_:       <>
bconsole (100): lib/tls_openssl_private.cc:572-0 Set certfile_:      <>
bconsole (100): lib/tls_openssl_private.cc:578-0 Set keyfile_:       <>
bconsole (100): lib/tls_openssl_private.cc:596-0 Set dhfile_:        <>
bconsole (100): lib/tls_openssl_private.cc:620-0 Set cipherlist:     <>
bconsole (100): lib/tls_openssl_private.cc:626-0 Set ciphersuites:   <>
bconsole (100): lib/tls_openssl_private.cc:602-0 Set Verify Peer:    <false>
bconsole (100): lib/tls_openssl_private.cc:608-0 Set ktls:   <true>
bconsole (50): lib/tls_openssl.cc:63-0 Preparing TLS_PSK CLIENT context for identity R_CONSOLE *UserAgent*
bconsole (100): lib/tls_openssl_private.cc:541-0 psk_client_cb. identity: R_CONSOLE *UserAgent*.
bconsole (150): lib/tls_openssl_private.cc:436-0 Ktls used for Recv: no
bconsole (150): lib/tls_openssl_private.cc:437-0 Ktls used for Send: yes
[...]

TLS Restricting Protocol and Cipher

With TLS/PSK activated by default in Bareos since version 18, it is sometimes mandatory to achieve better performance and increase the throughput of backups and restores. To do so, you need to fine-tune the configuration, selecting wisely the protocol and ciphers used. Syntax and parameter usage is far from evident. To do that, we only need to change two parameters into bareos configuration files, but their syntax and the location are a bit complex.

This chapter will show you how to do that.

Note

Since TLS protocols below 1.2 are considered weak, we will concentrate efforts on restricting cipher usage to protocol version 1.2 and above.

Determine available ciphers for TLSv1.2

The following command openssl helps to determine which ciphers are available for protocol 1.2 with the needed PSK extensions.

openssl list available ciphers for tls v1.2 with psk

openssl ciphers -tls1_2 -psk -s

Adding -v option will give you an output list in column mode.

Example of column output excluding SSLv3 and SHA1.

openssl verbose cipher list for tls v1.2 with psk filtering SSLv2 and SHA1

openssl ciphers -v -tls1_2 -psk -s | grep -v SSLv3 | grep -v Mac=SHA1


Example output list of ciphers:

   ECDHE-ECDSA-AES256-GCM-SHA384 TLSv1.2 Kx=ECDH     Au=ECDSA Enc=AESGCM(256) Mac=AEAD
   ECDHE-RSA-AES256-GCM-SHA384 TLSv1.2 Kx=ECDH     Au=RSA  Enc=AESGCM(256) Mac=AEAD
   ECDHE-ECDSA-CHACHA20-POLY1305 TLSv1.2 Kx=ECDH     Au=ECDSA Enc=CHACHA20/POLY1305(256) Mac=AEAD
   ECDHE-RSA-CHACHA20-POLY1305 TLSv1.2 Kx=ECDH     Au=RSA  Enc=CHACHA20/POLY1305(256) Mac=AEAD
   ECDHE-ECDSA-AES256-CCM  TLSv1.2 Kx=ECDH     Au=ECDSA Enc=AESCCM(256) Mac=AEAD
   ECDHE-ECDSA-AES128-GCM-SHA256 TLSv1.2 Kx=ECDH     Au=ECDSA Enc=AESGCM(128) Mac=AEAD
   ECDHE-RSA-AES128-GCM-SHA256 TLSv1.2 Kx=ECDH     Au=RSA  Enc=AESGCM(128) Mac=AEAD
   ECDHE-ECDSA-AES128-CCM  TLSv1.2 Kx=ECDH     Au=ECDSA Enc=AESCCM(128) Mac=AEAD
   ECDHE-ECDSA-AES128-SHA256 TLSv1.2 Kx=ECDH     Au=ECDSA Enc=AES(128)  Mac=SHA256
   ECDHE-RSA-AES128-SHA256 TLSv1.2 Kx=ECDH     Au=RSA  Enc=AES(128)  Mac=SHA256
   AES256-GCM-SHA384       TLSv1.2 Kx=RSA      Au=RSA  Enc=AESGCM(256) Mac=AEAD
   AES256-CCM              TLSv1.2 Kx=RSA      Au=RSA  Enc=AESCCM(256) Mac=AEAD
   AES128-GCM-SHA256       TLSv1.2 Kx=RSA      Au=RSA  Enc=AESGCM(128) Mac=AEAD
   AES128-CCM              TLSv1.2 Kx=RSA      Au=RSA  Enc=AESCCM(128) Mac=AEAD
   AES256-SHA256           TLSv1.2 Kx=RSA      Au=RSA  Enc=AES(256)  Mac=SHA256
   AES128-SHA256           TLSv1.2 Kx=RSA      Au=RSA  Enc=AES(128)  Mac=SHA256
   DHE-RSA-AES256-GCM-SHA384 TLSv1.2 Kx=DH       Au=RSA  Enc=AESGCM(256) Mac=AEAD
   DHE-RSA-CHACHA20-POLY1305 TLSv1.2 Kx=DH       Au=RSA  Enc=CHACHA20/POLY1305(256) Mac=AEAD
   DHE-RSA-AES256-CCM      TLSv1.2 Kx=DH       Au=RSA  Enc=AESCCM(256) Mac=AEAD
   DHE-RSA-AES128-GCM-SHA256 TLSv1.2 Kx=DH       Au=RSA  Enc=AESGCM(128) Mac=AEAD
   DHE-RSA-AES128-CCM      TLSv1.2 Kx=DH       Au=RSA  Enc=AESCCM(128) Mac=AEAD
   DHE-RSA-AES256-SHA256   TLSv1.2 Kx=DH       Au=RSA  Enc=AES(256)  Mac=SHA256
   DHE-RSA-AES128-SHA256   TLSv1.2 Kx=DH       Au=RSA  Enc=AES(128)  Mac=SHA256
   PSK-AES256-GCM-SHA384   TLSv1.2 Kx=PSK      Au=PSK  Enc=AESGCM(256) Mac=AEAD
   PSK-CHACHA20-POLY1305   TLSv1.2 Kx=PSK      Au=PSK  Enc=CHACHA20/POLY1305(256) Mac=AEAD
   PSK-AES256-CCM          TLSv1.2 Kx=PSK      Au=PSK  Enc=AESCCM(256) Mac=AEAD
   PSK-AES128-GCM-SHA256   TLSv1.2 Kx=PSK      Au=PSK  Enc=AESGCM(128) Mac=AEAD
   PSK-AES128-CCM          TLSv1.2 Kx=PSK      Au=PSK  Enc=AESCCM(128) Mac=AEAD
   PSK-AES128-CBC-SHA256   TLSv1 Kx=PSK      Au=PSK  Enc=AES(128)  Mac=SHA256
   DHE-PSK-AES256-GCM-SHA384 TLSv1.2 Kx=DHEPSK   Au=PSK  Enc=AESGCM(256) Mac=AEAD
   DHE-PSK-CHACHA20-POLY1305 TLSv1.2 Kx=DHEPSK   Au=PSK  Enc=CHACHA20/POLY1305(256) Mac=AEAD
   DHE-PSK-AES256-CCM      TLSv1.2 Kx=DHEPSK   Au=PSK  Enc=AESCCM(256) Mac=AEAD
   DHE-PSK-AES128-GCM-SHA256 TLSv1.2 Kx=DHEPSK   Au=PSK  Enc=AESGCM(128) Mac=AEAD
   DHE-PSK-AES128-CCM      TLSv1.2 Kx=DHEPSK   Au=PSK  Enc=AESCCM(128) Mac=AEAD
   DHE-PSK-AES128-CBC-SHA256 TLSv1 Kx=DHEPSK   Au=PSK  Enc=AES(128)  Mac=SHA256
   ECDHE-PSK-CHACHA20-POLY1305 TLSv1.2 Kx=ECDHEPSK Au=PSK  Enc=CHACHA20/POLY1305(256) Mac=AEAD
   ECDHE-PSK-AES128-CBC-SHA256 TLSv1 Kx=ECDHEPSK Au=PSK  Enc=AES(128)  Mac=SHA256
   RSA-PSK-AES256-GCM-SHA384 TLSv1.2 Kx=RSAPSK   Au=RSA  Enc=AESGCM(256) Mac=AEAD
   RSA-PSK-CHACHA20-POLY1305 TLSv1.2 Kx=RSAPSK   Au=RSA  Enc=CHACHA20/POLY1305(256) Mac=AEAD
   RSA-PSK-AES128-GCM-SHA256 TLSv1.2 Kx=RSAPSK   Au=RSA  Enc=AESGCM(128) Mac=AEAD
   RSA-PSK-AES128-CBC-SHA256 TLSv1 Kx=RSAPSK   Au=RSA  Enc=AES(128)  Mac=SHA256

From that list we propose to use the following ciphers list:

Note

ECDHE-RSA-AES128-GCM-SHA256 ECDHE-RSA-AES256-GCM-SHA384 PSK-AES128-GCM-SHA256 AES128-GCM-SHA256 PSK-AES256-GCM-SHA384 AES256-GCM-SHA384

Order is done by level of “most secure” label done by [ciphersuite.info](https://ciphersuite.info/) website, then by ascending strength of digest to minimize cpu impact. Note the importance to have some cipher with PSK in its name to support the TLS/PSK mechanism.

Just be sure they are present on all hosts you want to use with Bareos.

Determine available ciphers for TLSv1.3

Similar to TLSv1.2 we can list the supported ciphers with

openssl list available ciphers for tls v1.3

openssl ciphers -tls1_3 -psk -s

Currently only SHA256 ciphers are supported by bareos.

openssl verbose cipher list for tls v1.3 with psk filtering for SHA256

openssl ciphers -v -tls1_3 -psk -s | grep SHA256


Example output list of ciphers:

   TLS_CHACHA20_POLY1305_SHA256   TLSv1.3 Kx=any      Au=any   Enc=CHACHA20/POLY1305(256) Mac=AEAD
   TLS_AES_128_GCM_SHA256         TLSv1.3 Kx=any      Au=any   Enc=AESGCM(128)            Mac=AEAD
   TLS_AES_128_CCM_SHA256         TLSv1.3 Kx=any      Au=any   Enc=AESCCM(128)            Mac=AEAD

Since all available TLSv1.3 ciphers are fairly strong, we recommend to not set the ciphersuites manually unless needed; for example to enable Kernel TLS.

Resources parameters to configure

We will modify the following options

On Bareos Director

TLS Protocol (Dir->Director)

TLS Cipher List (Dir->Director)

TLS Protocol (Dir->Console)

TLS Cipher List (Dir->Console)

TLS Protocol (Dir->Client)

TLS Cipher List (Dir->Client)

TLS Protocol (Dir->Storage)

TLS Cipher List (Dir->Storage)

On Bareos File Daemon

TLS Protocol (Fd->Client)

TLS Cipher List (Fd->Client)

TLS Protocol (Fd->Director)

TLS Cipher List (Fd->Director)

On Bareos Storage Daemon

TLS Protocol (Sd->Storage)

TLS Cipher List (Sd->Storage)

TLS Protocol (Sd->Director)

TLS Cipher List (Sd->Director)

For bconsole

TLS Protocol (Console->Console)

TLS Cipher List (Console->Console)

In the following example, we will remove all protocols below 1.2 and 1.3, and activate specifically 1.2 if it is not by default.

The order of the list of ciphers that should normally be hardware accelerated and usable by kernel Kernel TLS, is important.

Both values need to be set as strings enclosed by double quotes.

TLS Protocol and TLS Cipher List Restricted syntax values

...
TLS Protocol = "-TLSv1,-TLSv1.1,-TLSv1.3,TLSv1.2"
TLS Cipher List = "ECDHE-RSA-AES128-GCM-SHA256:ECDHE-RSA-AES256-GCM-SHA384:AES128-GCM-SHA256:PSK-AES128-GCM-SHA256:AES256-GCM-SHA384:PSK-AES256-GCM-SHA384"
...

Those parameters have to be included in each resource located at (filenames in default installation).

List of configuration files where to apply changes

 bareos-dir.d/director/bareos-dir.conf
 bareos-dir.d/client/bareos-fd.conf
 bareos-dir.d/storage/File.conf

 bareos-fd.d/client/myself.conf
 bareos-fd.d/director/bareos-dir.conf

 bareos-sd.d/storage/bareos-sd.conf
 bareos-sd.d/director/bareos-dir.conf

 bconsole.conf

How to test protocol and ciphers

Testing the protocol in use and supported ciphers can be done with the nmap tool.

testing protocol and cipher with nmap

# director
nmap --script ssl-enum-ciphers -p 9101 -n localhost

# fd
nmap --script ssl-enum-ciphers -p 9102 -n localhost

# sd
nmap --script ssl-enum-ciphers -p 9103 -n localhost

If your daemons are using exclusively ipv6 you have to use the nmap -6 option.

Example of default ciphers for bareos-fd before restricted configuration

nmap --script ssl-enum-ciphers -p 9102 -n localhost

 Starting Nmap 7.93 ( https://nmap.org ) at 2022-11-22 14:25 CET
 Nmap scan report for localhost (::1)
 Host is up (0.000095s latency).
 Other addresses for localhost (not scanned): 127.0.0.1

 PORT     STATE SERVICE
 9102/tcp open  jetdirect
 | ssl-enum-ciphers:
 |   TLSv1.0:
 |     ciphers:
 |       TLS_ECDHE_PSK_WITH_AES_128_CBC_SHA (secp256r1) - A
 |       TLS_ECDHE_PSK_WITH_AES_128_CBC_SHA256 (secp256r1) - A
 |       TLS_ECDHE_PSK_WITH_AES_256_CBC_SHA (secp256r1) - A
 |       TLS_ECDHE_PSK_WITH_AES_256_CBC_SHA384 (secp256r1) - A
 |       TLS_ECDHE_PSK_WITH_CAMELLIA_128_CBC_SHA256 (secp256r1) - A
 |       TLS_ECDHE_PSK_WITH_CAMELLIA_256_CBC_SHA384 (secp256r1) - A
 |       TLS_PSK_WITH_AES_128_CBC_SHA - unknown
 |       TLS_PSK_WITH_AES_128_CBC_SHA256 - unknown
 |       TLS_PSK_WITH_AES_256_CBC_SHA - unknown
 |       TLS_PSK_WITH_AES_256_CBC_SHA384 - unknown
 |       TLS_PSK_WITH_CAMELLIA_128_CBC_SHA256 - unknown
 |       TLS_PSK_WITH_CAMELLIA_256_CBC_SHA384 - unknown
 |     compressors:
 |       NULL
 |     cipher preference: client
 |   TLSv1.1:
 |     ciphers:
 |       TLS_ECDHE_PSK_WITH_AES_128_CBC_SHA (secp256r1) - A
 |       TLS_ECDHE_PSK_WITH_AES_128_CBC_SHA256 (secp256r1) - A
 |       TLS_ECDHE_PSK_WITH_AES_256_CBC_SHA (secp256r1) - A
 |       TLS_ECDHE_PSK_WITH_AES_256_CBC_SHA384 (secp256r1) - A
 |       TLS_ECDHE_PSK_WITH_CAMELLIA_128_CBC_SHA256 (secp256r1) - A
 |       TLS_ECDHE_PSK_WITH_CAMELLIA_256_CBC_SHA384 (secp256r1) - A
 |       TLS_PSK_WITH_AES_128_CBC_SHA - unknown
 |       TLS_PSK_WITH_AES_128_CBC_SHA256 - unknown
 |       TLS_PSK_WITH_AES_256_CBC_SHA - unknown
 |       TLS_PSK_WITH_AES_256_CBC_SHA384 - unknown
 |       TLS_PSK_WITH_CAMELLIA_128_CBC_SHA256 - unknown
 |       TLS_PSK_WITH_CAMELLIA_256_CBC_SHA384 - unknown
 |     compressors:
 |       NULL
 |     cipher preference: client
 |   TLSv1.2:
 |     ciphers:
 |       TLS_ECDHE_PSK_WITH_AES_128_CBC_SHA (secp256r1) - A
 |       TLS_ECDHE_PSK_WITH_AES_128_CBC_SHA256 (secp256r1) - A
 |       TLS_ECDHE_PSK_WITH_AES_256_CBC_SHA (secp256r1) - A
 |       TLS_ECDHE_PSK_WITH_AES_256_CBC_SHA384 (secp256r1) - A
 |       TLS_ECDHE_PSK_WITH_CAMELLIA_128_CBC_SHA256 (secp256r1) - A
 |       TLS_ECDHE_PSK_WITH_CAMELLIA_256_CBC_SHA384 (secp256r1) - A
 |       TLS_ECDHE_PSK_WITH_CHACHA20_POLY1305_SHA256 (secp256r1) - A
 |       TLS_PSK_WITH_AES_128_CBC_SHA - unknown
 |       TLS_PSK_WITH_AES_128_CBC_SHA256 - unknown
 |       TLS_PSK_WITH_AES_128_CCM - unknown
 |       TLS_PSK_WITH_AES_128_CCM_8 - unknown
 |       TLS_PSK_WITH_AES_128_GCM_SHA256 - unknown
 |       TLS_PSK_WITH_AES_256_CBC_SHA - unknown
 |       TLS_PSK_WITH_AES_256_CBC_SHA384 - unknown
 |       TLS_PSK_WITH_AES_256_CCM - unknown
 |       TLS_PSK_WITH_AES_256_CCM_8 - unknown
 |       TLS_PSK_WITH_AES_256_GCM_SHA384 - unknown
 |       TLS_PSK_WITH_ARIA_128_GCM_SHA256 - unknown
 |       TLS_PSK_WITH_ARIA_256_GCM_SHA384 - unknown
 |       TLS_PSK_WITH_CAMELLIA_128_CBC_SHA256 - unknown
 |       TLS_PSK_WITH_CAMELLIA_256_CBC_SHA384 - unknown
 |       TLS_PSK_WITH_CHACHA20_POLY1305_SHA256 - unknown
 |     compressors:
 |       NULL
 |     cipher preference: client
 |_  least strength: unknown

 Nmap done: 1 IP address (1 host up) scanned in 0.23 seconds

To be compared to the following output when restricted protocol and cipher are in place.

Example of TLS restricted protocol and ciphers for bareos-fd only TLS-PSK

nmap --script ssl-enum-ciphers -p 9102 -n localhost

 Starting Nmap 7.93 ( https://nmap.org ) at 2022-11-22 14:50 CET
 Nmap scan report for localhost (127.0.0.1)
 Host is up (0.000057s latency).
 Other addresses for localhost (not scanned): ::1

 PORT     STATE SERVICE
 9101/tcp open  jetdirect
 | ssl-enum-ciphers:
 |   TLSv1.2:
 |     ciphers:
 |       TLS_PSK_WITH_AES_128_GCM_SHA256 - unknown
 |       TLS_PSK_WITH_AES_256_GCM_SHA384 - unknown
 |     compressors:
 |       NULL
 |     cipher preference: client
 |     warnings:
 |       Forward Secrecy not supported by any cipher
 |_  least strength: unknown

 Nmap done: 1 IP address (1 host up) scanned in 0.28 seconds

With the restricted configuration in place, the signature in bconsole will reflect the changes.

director connection with restricted TLS protocol and ciphers

bconsole

 Connecting to Director localhost:9101
   Encryption: PSK-AES128-GCM-SHA256 TLSv1.2
 1000 OK: bareos-dir Version: 21.1.5 (09 November 2022)

Conclusion

You are now able to configure TLS Protocol and cipher list to match your needs. Once this is in place we highly recommend comparing with real jobs the gain or loss of performance.

Transport Encryption

TLS Configuration Directives

Getting TLS Certificates

Example TLS Configuration Files

Bareos Director

Bareos Storage Daemon

Bareos File Daemon

Compatibility with Bareos File Daemon

Bareos File Daemon connection handshake probing

Bareos File Daemon 18.2 with Bareos before 18.2

Bareos Director configuration

Bareos Storage Daemon configuration

Bareos File Daemon configuration before 18.2

Bareos File Daemon before 18.2 with Bareos 18.2

Bareos File Daemon configuration

Bareos Webui

Configuration example

Overview of the settings in the Bareos Webui directors.ini file

TLS Configuration Reference

Enabling Kernel TLS

TLS Restricting Protocol and Cipher

Determine available ciphers for TLSv1.2

Determine available ciphers for TLSv1.3

Resources parameters to configure

How to test protocol and ciphers

Conclusion

Overview of the settings in the Bareos Webui `directors.ini` file