mc-tool

Minecraft Manifest Json Editor / UUID Generator

Usage

• Offline use: Download Source.zip Here , unzip, open index.html in any browser.

• Online Use: Website

v1.1 Changelong

Added support to load any Manifest.json files.

Added option to export edited manifest.json to fully structured folders of a complete pack as `.zip" files.

Updated UUID key generation using deterministic algorithm. Refer to UUID Generation Documentation.

As opposed to the older version that used randomized entropy and inconsistent seed based generation. This method caused complications where it was impossible to retrieve keys by using the generated UUID. With the new algorithm, a single UUID can be decrypted back to obtain the key along the pair of said UUID.

Previews

vx-17, vy-89

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UUID Generations

1. Key to Version 4 UUID Generation (Using Forward Path) The code's deterministic algorithm, allow the same key to always produces the same UUID.

Modular arithmetic and character-to-byte mapping.

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I. Buffer Expansion (Deterministic Padding) When a submitted key is shorter <16 characters, the system expands it using a linear congruential logic to ensure enough entropy for a 32-character hex string.

• Formula: $NewChar = ((OriginalCharCode \times 17) \pmod{94}) + 33$
• Logic: Multiplying by a prime number (17) shuffles the bits so that similar keys (e.g., "Key1" and "Key2") produce significantly different buffers.

II. Offset Transformation The system uses unique Offsets to ensure the same key produces different UUIDs for different components (Header vs. Module).

• Header Offset: VALUE_X
• Module Offset: VALUE_Y
• Transformation: $ByteValue = (CharCode + Offset) \pmod{256}$

III. UUID Version 4 Compliance The resulting 32-character hex string is forced into the standard UUID structure.

• Format: 8-4-4-4-12 Used as a reference of structural basis.
• Version Bits: The 13th character is hardcoded to 4.
• Variant Bits: The 17th character is hardcoded to a.
• Result: xxxxxxxx-xxxx-4xxx-axxx-xxxxxxxxxxxx

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Forward path mentioned early on is a method to be brought forward which made it possible to reverse math used initially to backtrace retrieve original key by a small offset due to two character that was hardcoded in the UUID.

Hex to Byte Conversion

The system strips the hyphens from the UUID and converts the first 24 hex characters back into a 12 decimal bytes.

Inverse Offset Calculation

To recover the original character code, the code subtracts the known offset used during generation.

• Formula: $RecoveredCode = (ByteValue - Offset)$
• Handling Underflow: If the result falls below the printable ASCII range (32), the system wraps it back around:
  • $If (RecoveredCode &lt; 32) \implies RecoveredCode + 256$

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Limitations & Extra Notes

1. Truncation: The UUID format only has room for 128 bits of data. Hence, only the first 12 characters of any key can be perfectly recovered which is a specific requirement for this use case only.

2. Hardcoded Constants: The "Security" of the key depends entirely on the secrecy of the offsets (VALUE_X and VALUE_Y). If the offsets are known, the "encryption" is functionally equivalent to a Caesar Cipher. The match of this sequence was unintentional but was interesting enough to be included nonetheless.

3. Forced Bits: Since characters 13 and 17 in the UUID are hardcoded to 4 and a for compliance, the data originally mapped to those positions is lost and cannot be recovered during the backtrace.

4. The UUID Key usage allows alphanumeric characters along with printable ascii (Typically used for password combinations) up to 12 characters. Although seems like this is simplified, the possible simple combination of printable ascii combination (Small/Capital alphabets, numbers, symbols, spaces, etc.) goes up to 546,108,599,233,516,079,517,120 or 546 Septillion or 5.4x10^(23). Human brain can barely comprehend this number. To put into perspective, brute-force tool tests around 100 billion combinations per second, even so it would still take over 170,000 years to complete this 1-12 combination range. Safe to say users can take their time to come up with a unique combination ranging from 1 to 12 characters with no problem.

The math is done with (Number Of Character Variations) Powered by (Length of this combination), varies from 1 to 12 as the length and summed up as total value.