DigiDoc4j

DigiDoc4j is a Java library for digitally signing documents and creating digital signature containers of signed documents.

Features

• Creating ASiC-E
• Validating ASiC-E, BDOC, ASIC-S and DDOC containers
• Creating and validating detached XadES

How to use it

• Take a look at the examples
• See the full DigiDoc4j API description
• Explore the Wiki section
• Download the latest release
• See the library development guide. Your contribution and pull requests are more than welcome

ASiC-E (Associated Signature Container Extended) container format

• Has .asice or .sce extension.
• This format is default format since 2019.
• ASIC-E containers are in compliance with EU standards.
• Signatures are stored in XAdES format.
• Supports following signature formats:
  • LT (Long Term) - Signature with time-stamp and OCSP (both "regular" and AIA OCSP are supported).
  • LTA (Long Term Archival) - signature format has additional archival time-stamp to LT profile.
• .asice or .sce file is in fact a ZIP container with the signed files, the signatures and the protocol control information and can basically be opened by any program that recognizes the ZIP format.
• It is recommended not to use special characters in the data file’s name, i.e. it is suggested to use only the characters that are categorized as “unreserved” according to RFC3986 (https://datatracker.ietf.org/doc/html/rfc3986).

BDOC (Estonian specific implementation of Associated Signature Container Extended) container format

The support for creating BDOC-specific time-mark signatures was removed since DigiDoc4j version 5.2.0 in relation to discontinuation of time-mark-capable OCSP responders in 2023.

• Has .bdoc extension
• BDOC is a digital signature format developed in 2014 to replace the old, DDOC (DigiDoc) digital signature format.
• This format has been used as a default digital signature format in Estonia since 2015 until end of 2018.
• BDOC container is based on ASiC-E standard.
• Signatures are stored in XAdES format.
• Supports signature formats:
  • LT_TM (Long Term TimeMark) - signature has time-mark ensuring long-term provability of the authenticity of the signature. LT_TM signing support in DigiDoc4j was removed since version 5.2.0.
    • It is based on XAdES baseline LT signature format.
• .bdoc file is in fact a ZIP container with the signed files, the signatures and the protocol control information and can basically be opened by any program that recognizes the ZIP format.
• It is recommended not to use special characters in the data file’s name, i.e. it is suggested to use only the characters that are categorized as “unreserved” according to RFC3986 (https://datatracker.ietf.org/doc/html/rfc3986).

ASiC-S (Associated Signature Container Simple) container format

• Has .asics or .scs extension
• Container associates one data file with either:
  • one signature file containing one or more XAdES detached digital signature(s) that apply to it; or
  • one time assertion file containing a time assertion that apply to it.
• This format is used for timestamping the old DDOC containers in order to prove the inviolability of documents.

DDOC container format

• Has .ddoc extension
• An old DigiDoc digital signature format
• Since year 2015 it's recommended not to sign documents in the DDOC format. DDOC signing support in Digidoc4j was removed in 2018.
• It is based on XML Advanced Electronic Signatures (XAdES) format, corresponding to profile XAdES-X-L
• The DigiDoc container includes the source files (the files that were signed) as well as the signatures that are related to the signed file(s)
• Every signature contains the certificate, validity confirmation and the validity confirmation service certificate.

Documentation

• DigiDoc4j API
• Examples
• Wiki
• Architecture of ID-software
• Digital signature formats
• BDOC 2.1.2 specification
• DDOC specification

Requirements

• Java 8 or higher (since version 4.0.0-RC.1)
• Internet access to external services
  • OCSP (Online Certificate Status Protocol) - AIA OCSP URL from signer's certificate or default fallback value http://ocsp.sk.ee (for more information, see here)
  • EU TSL (European Commission's Trusted Status List) - default value https://ec.europa.eu/tools/lotl/eu-lotl.xml (for more information, see here)
  • All the EU member states' TL servers referred in the EU TSL. Note that this list may change. (e.g. https://sr.riik.ee/tsl/estonian-tsl.xml, https://sedediatid.mineco.gob.es/Prestadores/TSL/TSL.xml, https://dp.trustedlist.fi/fi-tl.xml etc.)
  • TSA (Time Stamping Authority) - default value http://tsa.sk.ee (for more information, see here)
  • AIA (Authority Information Access) CA issuers - missing certificates of certificate chains downloaded from the URLs referred to in existing certificates
  • Signature Policy documents, if applicable (e.g. https://www.sk.ee/repository/bdoc-spec21.pdf)

Maven

You can use the library as a Maven dependency from the Maven Central (http://mvnrepository.com/artifact/org.digidoc4j/digidoc4j)

<dependency>
	<groupId>org.digidoc4j</groupId>
	<artifactId>digidoc4j</artifactId>
	<version>5.x.x</version>
</dependency>

Licence

• LGPL (GNU Library General Public License, see LICENSE.LGPL)
• © Estonian Information System Authority

Support

Official builds are provided through releases. If you want support, you need to be using official builds. For assistance, contact us by email [email protected]. Additional information can be found in wiki Q&A and on ID.ee portal.

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Source code is provided on "as is" terms with no warranty (see license for more information). Do not file GitHub issues with generic support requests.