Junos OS

The master-password documentation says $ 9 $ format or $ 8 $ format.

https://www.juniper.net/documentation/en_US/junos/topics/topic-map/master-password-configuration-encryption.html#id-hardening-shared-secrets-in-junos-os

Do you know what the specific formats are?

Master password uses $8$ format.

$9$ format (existing format)  is used to encrypt secrets like the RADIUS password, IKE preshared keys, and other shared secrets in the Junos OS configuration. 

Hi

The $9 format employ an obfuscation algorithm to map strings (weak encryption). Encoding involves a header of starting noise, followed by string encoding under essentially a Vigenère cipher.

If you want a strong encryption for your configuration secrets, you can configure a master password. The master password is used to derive an encryption key that is used with AES256-GCM to encrypt configuration secrets. This new encryption method uses the $8$ formatted strings.

The $8$-encrypted passwords have the following format:

$8$crypt-algo$hash-algo$iterations$salt$iv$tag$encrypted. 

Hope this helps.

Hi all.

I have a similler question.

Is "$9$ format" junos term ? 

When I googled "$9$ format", but I cannot find general meaning.

In $9$ or $8$, what does the numbers mean ?

Regards,

Hi

The '$9' or '$8' represents the starting string in the encryted password(which is being shown in configuration) and indicate the type of encryption used.

eg:

"$9$01X/1EyM87s2alK2aZU.mO1R"

 $9 format in Juniper is similar to the type 7 in cisco

Regards

Hi, Is there a table for $ 9 format?

Hi 

$9 is not having a structured format unlike $8. It is encrypted by shifting the alphabets like a Vigenère cipher

https://en.wikipedia.org/wiki/Vigen%C3%A8re_cipher

Are there any more details on the algorithm for computing the $8$ strings? I have tried to generate one to match what we have in our config and I have not been successful. Firstly the salt/iv/tag don't properly decode using base64 because they are not properly padded. I am not sure if padding them gets me the right values or not. It is also possible that Juniper is adding some additional data into the AES256-GCM cipher which means this cannot be computed off box. 

from Crypto.Cipher import AES
from Crypto.Hash import SHA512
from Crypto.Protocol.KDF import PBKDF2

def junos_type8_encrypt(
    master_password: str, password: str, salt: bytes, nonce: bytes, rounds: int
):
    encryptionKey = PBKDF2(
        password=master_password,
        salt=salt,
        dkLen=32,
        count=rounds,
        hmac_hash_module=SHA512,
    )
    cipher = AES.new(key=encryptionKey, mode=AES.MODE_GCM, nonce=nonce)
    cipher_text, tag = cipher.encrypt_and_digest(plaintext=password.encode())

    encoded_text = base64.b64encode(cipher_text).decode()
    encoded_tag = base64.b64encode(tag).decode()
    encoded_salt = base64.b64encode(salt).decode()
    encoded_nonce = base64.b64encode(nonce).decode()
    return f"$8$aes256-gcm$hmac-sha2-512${rounds}${encoded_salt}${encoded_nonce}${encoded_tag}${encoded_text}"