sassoftware / relic

Relic is a service and a tool for adding digital signatures to operating system packages for Linux and Windows

relic is a multi-tool and server for package signing and working with hardware security modules (HSMs).

Package types

• RPM - RedHat packages
• DEB - Debian packages
• JAR - Java archives
• EXE (PE/COFF) - Windows executable
• MSI - Windows installer
• appx, appxbundle - Windows universal application
• CAB - Windows cabinet file
• CAT - Windows security catalog
• XAP - Silverlight and legacy Windows Phone applications
• PS1, PS1XML, MOF, etc. - Microsoft Powershell scripts and modules
• manifest, application - Microsoft ClickOnce manifest
• VSIX - Visual Studio extension
• Mach-O - macOS/iOS signed executables
• DMG, PKG - macOS disk images / installer packages
• APK - Android package
• PGP - inline, detached or cleartext signature of data

Token types

relic can work with several types of token:

• pkcs11 - Industry standard PKCS#11 HSM interface using shared object files
• Cloud services - AWS, Azure and Google Cloud managed keys
• scdaemon - The GnuPG scdaemon service can enable access to OpenPGP cards (such as Yubikey NEO)
• file - Private keys stored in a password-protected file

Features

Relic is primarily meant to operate as a signing server, allowing clients to authenticate with a TLS certificate and sign packages remotely. It can also be used as a standalone signing tool.

Other features include:

• Generating and importing keys in the token
• Importing certificate chains from a PKCS#12 file
• Creating X509 certificate signing requests (CSR) and self-signed certificates
• Limited X509 CA support -- signing CSRs and cross-signing certificates
• Creating simple PGP public keys
• RSA and ECDSA supported for all non-PGP signature types (due to a limitation in the underlying PGP implementation, ECDSA is not currently possible for PGP signature types)
• Verify signatures, certificate chains and timestamps on all supported package types
• Save token PINs in the system keyring

Platforms

Linux, Windows and MacOS are supported. Other platforms probably work as well.

relic is tested using libsofthsm2. Every vendor PKCS#11 implementation has quirks, so if relic doesn't work with your hardware please submit a pull request.

Installation

Pre-built client binaries are available from the Github releases page. Alternately, relic can be built from source:

go install github.com/sassoftware/relic/v8@latest

The following build tags are also available:

• clientonly - build a lightweight binary without standalone signing features

See doc/relic.yml for an example configuration.

Additional documentation

• Signing Android packages
• Signing MacOS binaries
• Using Azure Key Vault
• Using a PGP card, YubiKey etc.

Related projects

• SoftHSMv2 - file-based PKCS#11 implementation for testing https://github.com/opendnssec/SoftHSMv2
• uts-server - timestamping server for testing https://github.com/kakwa/uts-server
• osslsigncode - Signs EXEs, MSIs, and CABs using openssl https://sourceforge.net/projects/osslsigncode/
• fb-util-for-appx - Builds signed APPX archives https://github.com/facebook/fb-util-for-appx
• OpenVsixSignTool - Sign VSIX extensions using an Azure key vault https://github.com/vcsjones/OpenVsixSignTool

Reference specifications

• PE/COFF specification - https://www.microsoft.com/en-us/download/details.aspx?id=19509
• Authenticode PE specification - http://download.microsoft.com/download/9/c/5/9c5b2167-8017-4bae-9fde-d599bac8184a/Authenticode_PE.docx
• Microsoft ClickOnce manifest structure - https://msdn.microsoft.com/en-us/library/dd947276(v=office.12).aspx
• Microsoft Compound File format (for MSI) - https://msdn.microsoft.com/en-us/library/dd942138.aspx
• Alternate reference for compound document format from OpenOffice - https://www.openoffice.org/sc/compdocfileformat.pdf