Does the FLEX50/200 support CBC for VPN?

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StefanZ
StefanZ Posts: 190  Master Member
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I am looking to connect a Yealink T48 IPphone via VPN to a FLEX50 or FLEX200.

#1 Here is a guide I found: OpenVPN Yealink VPN

#2 Another guide (in German): Yealink VPN German

This explains possible cypher options:
Yealink devices support no other hash algos than SHA1 or MD5!.
Supported ciphers are AES-128-CBC, AES-256-CBC or BF-CBC.

So before I dive into this, I'd rather ask :-)

Would this be feasible?

Best Answers

  • Zyxel_James
    Zyxel_James Posts: 616  Zyxel Employee
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    Hello @StefanZ

    you can check the cipher by

    Router(config)# show ip http server secure cipher-list

    Then you will see AES-128-CBC and AES-256-CBC

  • Zyxel_James
    Zyxel_James Posts: 616  Zyxel Employee
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    Hello @StefanZ

    The stronger ciphers are enabled by default. Please disable it first and check the cipher list again.
    Router# configure terminal
    Router(config)# no ip http secure-server strong-cipher
    Router(config)# show ip http server secure cipher-list

    Current available cipher suites:

    TLS_AES_256_GCM_SHA384 TLSv1.3 Kx=any Au=any Enc=AESGCM(256) Mac=AEAD
    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
    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-ARIA256-GCM-SHA384 TLSv1.2 Kx=ECDH Au=ECDSA Enc=ARIAGCM(256) Mac=AEAD
    ECDHE-ARIA256-GCM-SHA384 TLSv1.2 Kx=ECDH Au=RSA Enc=ARIAGCM(256) Mac=AEAD
    ECDHE-ECDSA-ARIA128-GCM-SHA256 TLSv1.2 Kx=ECDH Au=ECDSA Enc=ARIAGCM(128) Mac=AEAD
    ECDHE-ARIA128-GCM-SHA256 TLSv1.2 Kx=ECDH Au=RSA Enc=ARIAGCM(128) Mac=AEAD
    RSA-PSK-CHACHA20-POLY1305 TLSv1.2 Kx=RSAPSK Au=RSA Enc=CHACHA20/POLY1305(256) Mac=AEAD
    DHE-PSK-CHACHA20-POLY1305 TLSv1.2 Kx=DHEPSK Au=PSK Enc=CHACHA20/POLY1305(256) Mac=AEAD
    ECDHE-PSK-CHACHA20-POLY1305 TLSv1.2 Kx=ECDHEPSK Au=PSK Enc=CHACHA20/POLY1305(256) Mac=AEAD
    RSA-PSK-ARIA256-GCM-SHA384 TLSv1.2 Kx=RSAPSK Au=RSA Enc=ARIAGCM(256) Mac=AEAD
    DHE-PSK-ARIA256-GCM-SHA384 TLSv1.2 Kx=DHEPSK Au=PSK Enc=ARIAGCM(256) Mac=AEAD
    PSK-CHACHA20-POLY1305 TLSv1.2 Kx=PSK Au=PSK Enc=CHACHA20/POLY1305(256) Mac=AEAD
    PSK-ARIA256-GCM-SHA384 TLSv1.2 Kx=PSK Au=PSK Enc=ARIAGCM(256) Mac=AEAD
    RSA-PSK-ARIA128-GCM-SHA256 TLSv1.2 Kx=RSAPSK Au=RSA Enc=ARIAGCM(128) Mac=AEAD
    DHE-PSK-ARIA128-GCM-SHA256 TLSv1.2 Kx=DHEPSK Au=PSK Enc=ARIAGCM(128) Mac=AEAD
    PSK-ARIA128-GCM-SHA256 TLSv1.2 Kx=PSK Au=PSK Enc=ARIAGCM(128) Mac=AEAD
    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-AES256-CCM8 TLSv1.2 Kx=ECDH Au=ECDSA Enc=AESCCM8(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-CCM8 TLSv1.2 Kx=ECDH Au=ECDSA Enc=AESCCM8(128) Mac=AEAD
    ECDHE-ECDSA-AES128-CCM TLSv1.2 Kx=ECDH Au=ECDSA Enc=AESCCM(128) Mac=AEAD
    ECDHE-ECDSA-AES256-SHA384 TLSv1.2 Kx=ECDH Au=ECDSA Enc=AES(256) Mac=SHA384
    ECDHE-ECDSA-AES128-SHA256 TLSv1.2 Kx=ECDH Au=ECDSA Enc=AES(128) Mac=SHA256
    ECDHE-ECDSA-AES256-SHA TLSv1 Kx=ECDH Au=ECDSA Enc=AES(256) Mac=SHA1
    ECDHE-ECDSA-AES128-SHA TLSv1 Kx=ECDH Au=ECDSA Enc=AES(128) Mac=SHA1
    RSA-PSK-AES256-GCM-SHA384 TLSv1.2 Kx=RSAPSK Au=RSA Enc=AESGCM(256) Mac=AEAD
    DHE-PSK-AES256-GCM-SHA384 TLSv1.2 Kx=DHEPSK Au=PSK Enc=AESGCM(256) Mac=AEAD
    DHE-PSK-AES256-CCM8 TLSv1.2 Kx=DHEPSK Au=PSK Enc=AESCCM8(256) Mac=AEAD
    DHE-PSK-AES256-CCM TLSv1.2 Kx=DHEPSK Au=PSK Enc=AESCCM(256) Mac=AEAD
    PSK-AES256-GCM-SHA384 TLSv1.2 Kx=PSK Au=PSK Enc=AESGCM(256) Mac=AEAD
    PSK-AES256-CCM8 TLSv1.2 Kx=PSK Au=PSK Enc=AESCCM8(256) Mac=AEAD
    PSK-AES256-CCM TLSv1.2 Kx=PSK Au=PSK Enc=AESCCM(256) Mac=AEAD
    RSA-PSK-AES128-GCM-SHA256 TLSv1.2 Kx=RSAPSK Au=RSA Enc=AESGCM(128) Mac=AEAD
    DHE-PSK-AES128-GCM-SHA256 TLSv1.2 Kx=DHEPSK Au=PSK Enc=AESGCM(128) Mac=AEAD
    DHE-PSK-AES128-CCM8 TLSv1.2 Kx=DHEPSK Au=PSK Enc=AESCCM8(128) Mac=AEAD
    DHE-PSK-AES128-CCM TLSv1.2 Kx=DHEPSK Au=PSK Enc=AESCCM(128) Mac=AEAD
    PSK-AES128-GCM-SHA256 TLSv1.2 Kx=PSK Au=PSK Enc=AESGCM(128) Mac=AEAD
    PSK-AES128-CCM8 TLSv1.2 Kx=PSK Au=PSK Enc=AESCCM8(128) Mac=AEAD
    PSK-AES128-CCM TLSv1.2 Kx=PSK Au=PSK Enc=AESCCM(128) Mac=AEAD
    ECDHE-PSK-AES256-CBC-SHA384 TLSv1 Kx=ECDHEPSK Au=PSK Enc=AES(256) Mac=SHA384
    ECDHE-PSK-AES256-CBC-SHA TLSv1 Kx=ECDHEPSK Au=PSK Enc=AES(256) Mac=SHA1
    SRP-DSS-AES-256-CBC-SHA SSLv3 Kx=SRP Au=DSS Enc=AES(256) Mac=SHA1
    SRP-RSA-AES-256-CBC-SHA SSLv3 Kx=SRP Au=RSA Enc=AES(256) Mac=SHA1
    SRP-AES-256-CBC-SHA SSLv3 Kx=SRP Au=SRP Enc=AES(256) Mac=SHA1
    RSA-PSK-AES256-CBC-SHA384 TLSv1 Kx=RSAPSK Au=RSA Enc=AES(256) Mac=SHA384
    DHE-PSK-AES256-CBC-SHA384 TLSv1 Kx=DHEPSK Au=PSK Enc=AES(256) Mac=SHA384
    RSA-PSK-AES256-CBC-SHA SSLv3 Kx=RSAPSK Au=RSA Enc=AES(256) Mac=SHA1
    DHE-PSK-AES256-CBC-SHA SSLv3 Kx=DHEPSK Au=PSK Enc=AES(256) Mac=SHA1
    PSK-AES256-CBC-SHA384 TLSv1 Kx=PSK Au=PSK Enc=AES(256) Mac=SHA384
    PSK-AES256-CBC-SHA SSLv3 Kx=PSK Au=PSK Enc=AES(256) Mac=SHA1
    ECDHE-PSK-AES128-CBC-SHA256 TLSv1 Kx=ECDHEPSK Au=PSK Enc=AES(128) Mac=SHA256
    ECDHE-PSK-AES128-CBC-SHA TLSv1 Kx=ECDHEPSK Au=PSK Enc=AES(128) Mac=SHA1
    SRP-DSS-AES-128-CBC-SHA SSLv3 Kx=SRP Au=DSS Enc=AES(128) Mac=SHA1
    SRP-RSA-AES-128-CBC-SHA SSLv3 Kx=SRP Au=RSA Enc=AES(128) Mac=SHA1
    SRP-AES-128-CBC-SHA SSLv3 Kx=SRP Au

All Replies

  • Zyxel_James
    Zyxel_James Posts: 616  Zyxel Employee
    First Anniversary 10 Comments Friend Collector First Answer
    Answer ✓
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    Hello @StefanZ

    you can check the cipher by

    Router(config)# show ip http server secure cipher-list

    Then you will see AES-128-CBC and AES-256-CBC

  • StefanZ
    StefanZ Posts: 190  Master Member
    First Anniversary 10 Comments Friend Collector First Answer
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    Thank you James.

    The CLI output for the FLEX200 is:

    TLS_AES_256_GCM_SHA384 TLSv1.3 Kx=any Au=any Enc=AESGCM(256) Mac=AEAD
    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
    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
    DHE-RSA-AES256-GCM-SHA384 TLSv1.2 Kx=DH 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
    DHE-RSA-CHACHA20-POLY1305 TLSv1.2 Kx=DH Au=RSA Enc=CHACHA20/POLY1305(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
    DHE-RSA-AES128-GCM-SHA256 TLSv1.2 Kx=DH Au=RSA Enc=AESGCM(128) Mac=AEAD

    No CBC to be found – so connecting those phones won't work I guess.
    Or is there a way to activate/add CBC to the FLEX?

  • Zyxel_James
    Zyxel_James Posts: 616  Zyxel Employee
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    Answer ✓
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    Hello @StefanZ

    The stronger ciphers are enabled by default. Please disable it first and check the cipher list again.
    Router# configure terminal
    Router(config)# no ip http secure-server strong-cipher
    Router(config)# show ip http server secure cipher-list

    Current available cipher suites:

    TLS_AES_256_GCM_SHA384 TLSv1.3 Kx=any Au=any Enc=AESGCM(256) Mac=AEAD
    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
    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-ARIA256-GCM-SHA384 TLSv1.2 Kx=ECDH Au=ECDSA Enc=ARIAGCM(256) Mac=AEAD
    ECDHE-ARIA256-GCM-SHA384 TLSv1.2 Kx=ECDH Au=RSA Enc=ARIAGCM(256) Mac=AEAD
    ECDHE-ECDSA-ARIA128-GCM-SHA256 TLSv1.2 Kx=ECDH Au=ECDSA Enc=ARIAGCM(128) Mac=AEAD
    ECDHE-ARIA128-GCM-SHA256 TLSv1.2 Kx=ECDH Au=RSA Enc=ARIAGCM(128) Mac=AEAD
    RSA-PSK-CHACHA20-POLY1305 TLSv1.2 Kx=RSAPSK Au=RSA Enc=CHACHA20/POLY1305(256) Mac=AEAD
    DHE-PSK-CHACHA20-POLY1305 TLSv1.2 Kx=DHEPSK Au=PSK Enc=CHACHA20/POLY1305(256) Mac=AEAD
    ECDHE-PSK-CHACHA20-POLY1305 TLSv1.2 Kx=ECDHEPSK Au=PSK Enc=CHACHA20/POLY1305(256) Mac=AEAD
    RSA-PSK-ARIA256-GCM-SHA384 TLSv1.2 Kx=RSAPSK Au=RSA Enc=ARIAGCM(256) Mac=AEAD
    DHE-PSK-ARIA256-GCM-SHA384 TLSv1.2 Kx=DHEPSK Au=PSK Enc=ARIAGCM(256) Mac=AEAD
    PSK-CHACHA20-POLY1305 TLSv1.2 Kx=PSK Au=PSK Enc=CHACHA20/POLY1305(256) Mac=AEAD
    PSK-ARIA256-GCM-SHA384 TLSv1.2 Kx=PSK Au=PSK Enc=ARIAGCM(256) Mac=AEAD
    RSA-PSK-ARIA128-GCM-SHA256 TLSv1.2 Kx=RSAPSK Au=RSA Enc=ARIAGCM(128) Mac=AEAD
    DHE-PSK-ARIA128-GCM-SHA256 TLSv1.2 Kx=DHEPSK Au=PSK Enc=ARIAGCM(128) Mac=AEAD
    PSK-ARIA128-GCM-SHA256 TLSv1.2 Kx=PSK Au=PSK Enc=ARIAGCM(128) Mac=AEAD
    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-AES256-CCM8 TLSv1.2 Kx=ECDH Au=ECDSA Enc=AESCCM8(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-CCM8 TLSv1.2 Kx=ECDH Au=ECDSA Enc=AESCCM8(128) Mac=AEAD
    ECDHE-ECDSA-AES128-CCM TLSv1.2 Kx=ECDH Au=ECDSA Enc=AESCCM(128) Mac=AEAD
    ECDHE-ECDSA-AES256-SHA384 TLSv1.2 Kx=ECDH Au=ECDSA Enc=AES(256) Mac=SHA384
    ECDHE-ECDSA-AES128-SHA256 TLSv1.2 Kx=ECDH Au=ECDSA Enc=AES(128) Mac=SHA256
    ECDHE-ECDSA-AES256-SHA TLSv1 Kx=ECDH Au=ECDSA Enc=AES(256) Mac=SHA1
    ECDHE-ECDSA-AES128-SHA TLSv1 Kx=ECDH Au=ECDSA Enc=AES(128) Mac=SHA1
    RSA-PSK-AES256-GCM-SHA384 TLSv1.2 Kx=RSAPSK Au=RSA Enc=AESGCM(256) Mac=AEAD
    DHE-PSK-AES256-GCM-SHA384 TLSv1.2 Kx=DHEPSK Au=PSK Enc=AESGCM(256) Mac=AEAD
    DHE-PSK-AES256-CCM8 TLSv1.2 Kx=DHEPSK Au=PSK Enc=AESCCM8(256) Mac=AEAD
    DHE-PSK-AES256-CCM TLSv1.2 Kx=DHEPSK Au=PSK Enc=AESCCM(256) Mac=AEAD
    PSK-AES256-GCM-SHA384 TLSv1.2 Kx=PSK Au=PSK Enc=AESGCM(256) Mac=AEAD
    PSK-AES256-CCM8 TLSv1.2 Kx=PSK Au=PSK Enc=AESCCM8(256) Mac=AEAD
    PSK-AES256-CCM TLSv1.2 Kx=PSK Au=PSK Enc=AESCCM(256) Mac=AEAD
    RSA-PSK-AES128-GCM-SHA256 TLSv1.2 Kx=RSAPSK Au=RSA Enc=AESGCM(128) Mac=AEAD
    DHE-PSK-AES128-GCM-SHA256 TLSv1.2 Kx=DHEPSK Au=PSK Enc=AESGCM(128) Mac=AEAD
    DHE-PSK-AES128-CCM8 TLSv1.2 Kx=DHEPSK Au=PSK Enc=AESCCM8(128) Mac=AEAD
    DHE-PSK-AES128-CCM TLSv1.2 Kx=DHEPSK Au=PSK Enc=AESCCM(128) Mac=AEAD
    PSK-AES128-GCM-SHA256 TLSv1.2 Kx=PSK Au=PSK Enc=AESGCM(128) Mac=AEAD
    PSK-AES128-CCM8 TLSv1.2 Kx=PSK Au=PSK Enc=AESCCM8(128) Mac=AEAD
    PSK-AES128-CCM TLSv1.2 Kx=PSK Au=PSK Enc=AESCCM(128) Mac=AEAD
    ECDHE-PSK-AES256-CBC-SHA384 TLSv1 Kx=ECDHEPSK Au=PSK Enc=AES(256) Mac=SHA384
    ECDHE-PSK-AES256-CBC-SHA TLSv1 Kx=ECDHEPSK Au=PSK Enc=AES(256) Mac=SHA1
    SRP-DSS-AES-256-CBC-SHA SSLv3 Kx=SRP Au=DSS Enc=AES(256) Mac=SHA1
    SRP-RSA-AES-256-CBC-SHA SSLv3 Kx=SRP Au=RSA Enc=AES(256) Mac=SHA1
    SRP-AES-256-CBC-SHA SSLv3 Kx=SRP Au=SRP Enc=AES(256) Mac=SHA1
    RSA-PSK-AES256-CBC-SHA384 TLSv1 Kx=RSAPSK Au=RSA Enc=AES(256) Mac=SHA384
    DHE-PSK-AES256-CBC-SHA384 TLSv1 Kx=DHEPSK Au=PSK Enc=AES(256) Mac=SHA384
    RSA-PSK-AES256-CBC-SHA SSLv3 Kx=RSAPSK Au=RSA Enc=AES(256) Mac=SHA1
    DHE-PSK-AES256-CBC-SHA SSLv3 Kx=DHEPSK Au=PSK Enc=AES(256) Mac=SHA1
    PSK-AES256-CBC-SHA384 TLSv1 Kx=PSK Au=PSK Enc=AES(256) Mac=SHA384
    PSK-AES256-CBC-SHA SSLv3 Kx=PSK Au=PSK Enc=AES(256) Mac=SHA1
    ECDHE-PSK-AES128-CBC-SHA256 TLSv1 Kx=ECDHEPSK Au=PSK Enc=AES(128) Mac=SHA256
    ECDHE-PSK-AES128-CBC-SHA TLSv1 Kx=ECDHEPSK Au=PSK Enc=AES(128) Mac=SHA1
    SRP-DSS-AES-128-CBC-SHA SSLv3 Kx=SRP Au=DSS Enc=AES(128) Mac=SHA1
    SRP-RSA-AES-128-CBC-SHA SSLv3 Kx=SRP Au=RSA Enc=AES(128) Mac=SHA1
    SRP-AES-128-CBC-SHA SSLv3 Kx=SRP Au

  • StefanZ
    StefanZ Posts: 190  Master Member
    First Anniversary 10 Comments Friend Collector First Answer
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    Router# configure terminal
    Router(config)# no ip http secure-server strong-cipher

    This worked. Thank you so much!

    Now let's see if I get this phone connected…

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