open-pdf-sign – Digitally Sign PDF Documents

open-pdf-sign is a command-line application for adding cryptographic electronic signatures to PDF documents.

It supports several PAdES profiles, visible or invisible signatures, timestamp services and long-term validation data. Besides its normal command-line operation, the program can run as a server for integration with document-processing applications and automated signing workflows.

This is free and open source software.

Key Features

• Applies standards-based electronic signatures to existing PDF documents.
• Supports PAdES baseline B, T, LT and LTA signature profiles.
• Creates invisible signatures or places a visible signature on a selected page.
• Lets users configure the visible signature’s position, width, text and graphical appearance.
• Supports custom signature images as well as an image-only presentation mode.
• Accepts certificates and private keys from files or supported keystores.
• Handles certificate chains needed to establish trust in a generated signature.
• Supports password-protected source documents, private keys and keystores.
• Adds trusted timestamps using one or more configurable timestamp authorities.
• Can fall back to another timestamp authority if the preferred service is unavailable.
• Supports timestamp-service authentication and operation through a proxy.
• Can incorporate validation information needed for long-term signature verification.
• Provides document-certification options through supported DocMDP permission levels.
• Lets users add details such as the signing reason, location, contact information and signature hint.
• Supports configurable labels, languages, locales and time zones for visible signatures.
• Can add a blank page when a document needs additional space for a visible signature.
• Reads reusable configuration settings from YAML files.
• Offers a server mode that accepts signing requests through a JSON-based HTTP interface.
• Can write the resulting binary document to standard output for use in shell pipelines.

Website: github.com/open-pdf-sign/open-pdf-sign
Support:
Developer: Thomas Schreiber and Philipp Omenitsch
License: Apache License 2.0

open-pdf-sign is written in Java. Learn Java with our recommended free books and free tutorials.

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