Book Loader

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Adobe ACSM & Kobo KEPUB ebook DRM removal tool

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⚠️ LEGAL NOTICE AND USAGE RESTRICTIONS

READ CAREFULLY BEFORE USE

This software is provided strictly for educational, research, and personal backup purposes only. By using this tool, you acknowledge and agree to the following terms:

Legal Restrictions

1. Copyright Compliance: This tool must ONLY be used with ebooks that you have legally purchased or have explicit authorization to access. Unauthorized removal of DRM from copyrighted content may violate:

   • The Digital Millennium Copyright Act (DMCA) in the United States
   • The EU Copyright Directive
   • Similar copyright protection laws in your jurisdiction

2. Prohibited Activities: The following uses are STRICTLY PROHIBITED:

   • Commercial redistribution of DRM-free ebooks
   • Sharing DRM-free ebooks with unauthorized parties
   • Circumventing DRM for piracy or copyright infringement
   • Any use that violates the terms of service of ebook vendors

3. Personal Use Only: This tool is intended solely for creating personal backup copies of legitimately purchased ebooks for use across your own devices.

Disclaimer

• NO WARRANTY: This software is provided "AS IS" without warranty of any kind, express or implied.
• LIABILITY: The authors and contributors assume NO LIABILITY for any misuse, legal consequences, or damages arising from the use of this software.
• USER RESPONSIBILITY: Users are solely responsible for ensuring their use complies with applicable laws and terms of service in their jurisdiction.

Developer Statement

This project is developed for legitimate interoperability and personal backup purposes. The developers do not condone or support piracy, copyright infringement, or any illegal activity.

If you do not agree to these terms or cannot ensure legal compliance, DO NOT USE this software.

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Features

Adobe ACSM

• ✅ Process ACSM files, output DRM-free EPUB/PDF
• ✅ Support anonymous authorization (no Adobe account required)
• ✅ Support Adobe ID authorization (can be used on multiple devices)
• ✅ No need to install Adobe Digital Editions
• ✅ Backup and restore authorization (tar.gz archive)

Kobo Desktop (macOS)

• ✅ List all books in your Kobo Desktop library
• ✅ Remove KDRM from KEPUB files, output standard EPUB
• ✅ Interactive multi-select menu or batch decrypt all books

Installation

Requires Python 3.10 or later.

git clone https://github.com/spreered/book_loader.git
cd book_loader
pip install -e .

Usage

Quick Start

# Simplest way: process ACSM directly (will automatically create anonymous authorization)
book-loader process book.acsm

# Specify output directory
book-loader process book.acsm -o ~/Books/

Authorization Management

Create New Authorization

# Method 1: Anonymous authorization (default, no Adobe account required)
book-loader auth create --anonymous

# Method 2: Adobe ID authorization (can be used on up to 6 devices)
book-loader auth create --adobe-id --email your@email.com

# View authorization information
book-loader auth info

# Reset authorization (automatically creates a backup before deleting)
book-loader auth reset

Backup and Restore Authorization

# Backup authorization (interactive prompt for destination, default: ~/adobe-ade-auth-bk/)
book-loader auth backup

# Backup to a specific directory
book-loader auth backup -o ~/my-backups/

# Restore authorization (interactive menu to select from available backups)
book-loader auth restore

# Restore from a specific backup file
book-loader auth restore --file ~/adobe-ade-auth-bk/auth_AdobeID_20260217_004129.tar.gz

# Restore from backups in a specific directory
book-loader auth restore --backup-dir ~/my-backups/

Note: auth reset automatically creates a backup to ~/adobe-ade-auth-bk/ before deleting authorization files, so you can always restore if needed.

Using Existing Authorization (Advanced)

If you already have Adobe Digital Editions (ADE) authorization, you can use it directly:

# Use ADE's authorization directory
book-loader process book.acsm \
  --auth-dir ~/Library/Application\ Support/Adobe/Digital\ Editions/

# Or use custom authorization directory
book-loader process book.acsm --auth-dir /path/to/auth/

Note: ADE authorization directory may contain both anonymous and Adobe ID authorizations. The tool will prioritize:

• activation.xml + device.xml + devicesalt (old format authorization)
• activation.dat (ADE 4.5+ format)

Kobo DRM Removal (macOS)

Requires Kobo Desktop Edition to be installed and your library synced.

List Books

book-loader kobo list

Example output:

Found 11 book(s) in Kobo library:

#    Title                                            Author                       DRM
----------------------------------------------------------------------------------------
1    Book Title A                                     Author Name                  Protected
2    Book Title B                                     Author Name                  Protected

Decrypt Books

# Interactive multi-select menu (Space to select, Enter to confirm)
book-loader kobo dedrm

# Decrypt all books
book-loader kobo dedrm --all

# Decrypt all books to a specific directory
book-loader kobo dedrm --all -o ~/Books/

# Overwrite existing files without asking (non-interactive)
book-loader kobo dedrm --all --overwrite -o ~/Books/

# Skip existing files without asking (non-interactive)
book-loader kobo dedrm --all --skip-existing -o ~/Books/

The output EPUB files are named after the book title (special characters replaced with _).

File Conflict Handling:

• By default (interactive mode), you'll be prompted when a file already exists with options to:
  • Overwrite this file
  • Skip this file
  • Overwrite all remaining (batch mode only)
  • Skip all remaining (batch mode only)
  • Cancel operation
• Use --overwrite to automatically overwrite all existing files without prompting
• Use --skip-existing to automatically skip all existing files without prompting

Custom Library Path

By default, the tool looks for Kobo Desktop at ~/Library/Application Support/Kobo/Kobo Desktop Edition. Use --source to specify a different directory:

# --source goes between kobo and the subcommand
book-loader kobo --source /path/to/kobo list
book-loader kobo --source /path/to/kobo dedrm --all -o ~/Books/

Note: You must be logged in to Kobo Desktop with the same account that purchased the books. The decryption key is derived from your local machine's MAC address and Kobo account credentials — no internet connection is required.

System Information

# Display system information
book-loader info

Important Concepts

ACSM Files and Transaction ID

ACSM (Adobe Content Server Manager) is not the ebook itself, but a "download voucher":

1. Transaction ID is generated at purchase time

   • Each purchase generates a unique Transaction ID
   • Downloading ACSM for the same book on different devices has the same Transaction ID
   • Even if you re-download the ACSM, the Transaction ID remains the same

2. ACSM can only be fulfilled once

   • After fulfillment, ACSM is bound to a specific authorization
   • Adobe server records that this Transaction has been used
   • Cannot reuse the same ACSM on other devices or authorizations

3. How to check Transaction ID

   # View the Transaction ID of an ACSM
   grep transaction your-book.acsm
   
   # View Transaction IDs of all ACSMs
   grep transaction ~/Downloads/*.acsm

Authorization Type Comparison

Authorization Type	Account Required	Device Limit	Use Case
Anonymous	❌ No	⚠️ Single device only	Single device, privacy-focused
Adobe ID	✅ Yes	✅ Up to 6 devices	Multi-device sync

Multi-Device Usage Recommendations

❌ Wrong Approach:

# Fulfill ACSM on Device A
book-loader process book.acsm

# Fulfill the same ACSM again on Device B
book-loader process book.acsm  # ❌ Will fail! Transaction already used

✅ Correct Approach:

# Fulfill and remove DRM on Device A
book-loader process book.acsm -o ~/Books/
# Produces: ~/Books/book.epub (DRM-free)

# Copy the DRM-free file to Device B
# Can be used directly without re-fulfilling ACSM

FAQ

Q: Why do I get "E_LIC_ALREADY_FULFILLED_BY_ANOTHER_USER" error?

Reason: This ACSM (Transaction) has already been used by an authorization.

Possible scenarios:

1. Previously opened this book in Adobe Digital Editions
2. Processed this ACSM with other tools
3. Re-downloaded the same book's ACSM (same Transaction ID)

Solutions:

• If previously opened in ADE: Use --auth-dir to specify ADE's authorization directory
• If file was deleted: Cannot re-fulfill, need to find the original ebook file
• If it's a brand new book: Confirm it hasn't been opened with other authorizations

Q: How to check if a book has been fulfilled?

Check the UUID in the error message:

# Error message example:
# E_LIC_ALREADY_FULFILLED_BY_ANOTHER_USER ... urn:uuid:2b60b2eb-...

# View your authorization UUID
grep "user>" ~/.config/book-loader/.adobe/activation.xml

If the UUID matches, it was fulfilled by your authorization; if not, it was fulfilled by another authorization.

Q: Can I use multiple authorizations simultaneously?

Yes! Use --auth-dir to specify different authorization directories:

# Use authorization A
book-loader process book1.acsm --auth-dir ~/auth-a/

# Use authorization B
book-loader process book2.acsm --auth-dir ~/auth-b/

Q: How to backup authorization?

Use the built-in backup command:

# Interactive backup (prompts for destination, default: ~/adobe-ade-auth-bk/)
book-loader auth backup

# Backup to a specific directory
book-loader auth backup -o ~/my-backups/

The backup is saved as a .tar.gz archive with a timestamped filename (e.g., auth_AdobeID_20260217_004129.tar.gz).

To restore, use:

# Interactive restore (lists available backups)
book-loader auth restore

# Restore from a specific file
book-loader auth restore --file ~/adobe-ade-auth-bk/auth_AdobeID_20260217_004129.tar.gz

Note: auth reset automatically creates a backup before deleting, so you won't accidentally lose your authorization.

Q: Can I retry after processing fails?

Depends on the failure stage:

• ✅ Fulfillment succeeded, but download failed: Can retry (Transaction not consumed)
• ✅ DRM removal failed: Can retry (downloaded encrypted file still exists)
• ❌ Fulfillment succeeded and download complete: Transaction consumed, cannot retry

License

GPLv3

This project integrates the following open-source code:

• acsm-calibre-plugin - GPLv3
• DeDRM_tools (includes Obok for Kobo DRM removal)

Disclaimer

IMPORTANT: This tool is strictly for personal, legal use with legitimately purchased ebooks only.

Violating copyright laws or terms of service may result in civil and criminal penalties. Users bear full responsibility for ensuring their usage complies with all applicable laws and regulations in their jurisdiction.

The developers explicitly disclaim any responsibility for misuse of this software.