Support exporting Viber stickers

[laggykiller]

Stem from #144

I have attempted to reverse engineer Viber Android app. To export Viber stickers, we need to get member_id and udid, which should be the same for each user but not sure where they could be obtained. Even worse, we need to get m_token, which is changed everytime when app is restarted, and I have no idea how I can automatically get it.

This is best attempt for exporting Viber sticker, which obviously won't work works if you obtain member_id, m_token and m_ts and fill in:

import requests

viber_version = "22.4.3.0"
user_agent = f"Mozilla/5.0 (Linux; Android 11; Android SDK built for x86 Build/RSR1.210210.001.A1; wv) AppleWebKit/537.36 (KHTML, like Gecko) Version/4.0 Chrome/83.0.4103.106 Mobile Safari/537.36 Viber/{viber_version}"

# upload.zip: Zip file containing 490x490 png images to upload (00.png, 01.png, ...)
# color_icon.png: 120x120 png image
with open("upload.zip", "rb") as f, open("color_icon.png", "rb") as g:
    result = requests.post(
        "https://market.api.viber.com/2/users/custom-sticker-packs/create",
        files={
            "file": ("upload.zip", f),
            "file_icon": ("color_icon.png", g)
        },
        data={
            "member_id": "REDACTED",  # Same for each user
            "m_token": "REDACTED",  # Changed when app is restarted or after 13800seconds (230minutes)
            "m_ts": "1700000000000", # Unix timestamp with milisecond precision when m_token is generated (not when request is posted)
            "title": "my-custom-pack",
            "description": "My custom viber sticker pack",
            "shareable": "1",
            # "udid": "REDACTED",  # Same for each user  # Actually not necessary
            # "phone_country": "US",  # Actually not necessary
            # "mcc": "310",  # Mobile Country Codes, see https://mcc-mnc.com/  # Actually not necessary
            # "mnc": "260",  # Mobile Network Codes, see https://mcc-mnc.com/  # Actually not necessary
            # "vv": viber_version,  # Actually not necessary
            # "sid": "1",  # Actually not necessary
            # "lang": "en",  # Actually not necessary
            # "privacy_flags": "7",  # Actually not necessary
        },
        # headers={
        #     "User-Agent": user_agent # Actually not necessary
        # }
    )

    print(result.text)  # status should be 1 if success

If anyone want to reverse the Android app, I recommend using PCAPdroid on rooted Android emulator with mitm addon, with MagiskTrustUserCerts. Jadx decompilation might also be useful.

We can also analyze Windows version of Viber, but I am not familiar with it. What makes matter worse, Viber Windows start to store database with encrypted SQLCipher encryption using 128bit openssh private key(?) (Russian forum, use Google translate: https://4pda.to/forum/index.php?showtopic=714685&view=findpost&p=125818765), which means things like udid might be locked behind a database that is decrypted with unknown way.

If someone has solution, please comment / submit PR, thank you.

---

To do:

• How to obtain member_id?
  • Located in viber.db in %appdata%/ViberPC/<phone_number>/viber.db table Contact column MID row with ContactID of 1
  • Unfortunately viber.db is encrypted with 128bit openssh private key(?) in Viber PC 19.4.0+
  • How to get encryption key for viber.db?
  • Alternative solution 1: Dump memory from Viber desktop app and find member_id, which I have proved to work. However dumping memory on different OS requires different method, and it is slow.
  • Alternative solution 2: Ask user to install Viber PC with version 19.3.0 or lower. However this will no longer work when Viber make those versions obsolete.
• How to obtain m_token?
  • Seems like it is generated by resources/lib/<architecture>/libVoipEngineNative.so on Android, possibly generateSequence() +/- handleSecureTokenRequest() (?)
  • Seems like it is generated from communicating with some server (aloha46.viber.com followed by some random ip) using TCP, with communication encrypted by some way
• How to obtain udid?
  • From decompiling Viber Android with jadx, udid seems to be generated by sources.com.viber.voip.registration.x3.a. Is udid still required if we create sticker pack from Viber PC?
  • Actually not necessary for uploading stickers, let's just ignore it

[laggykiller]

From decompiling Viber Android with jadx, udid seems to be generated by sources.com.viber.voip.registration.x3.a

sources.com.viber.voip.registration.ActivationController is also interesting

EDIT: udid is actually not necessary