spid-go

Golang package for SPID authentication

This Go package is aimed at implementing SPID Service Providers. SPID is the Italian digital identity system, which enables citizens to access all public services with single set of credentials. This module provides a layer of abstraction over the SAML protocol by exposing just the subset required in order to implement SPID authentication in a web application.

Getting Started

The example/ directory contains a demo web application. Just follow these steps in order to test it with spid-saml-check:

1. Clone this package:

   git clone github.com/italia/spid-go
   cd spid-go

2. Install and run spid-saml-check as a Docker container (note: this bug in spid-saml-check prevents it from working with a non-HTTPS Service Provider so you'll have to apply a patch).

3. Get the Identity Provider metadata exposed by spid-saml-check:

   curl -o sample_data/test_idp/spid-saml-check.xml https://localhost:8443/metadata.xml

4. Run the demo Service Provider provided with this package:

   cd example
   go run service.go

5. Open the spid-saml-check interface at https://localhost:8443 and load the Service Provider metadata. Since spid-saml-check is running inside a Docker container, you'll have to use this URL: http://host.docker.internal:8000/metadata (if you want to open it from your browser, just use http://localhost:8000/metadata)

6. Perform (and enjoy) the metadata validation on spid-saml-check.

7. Open http://localhost:8000 and proceed with the full authentication test.

Generating your own key

If you want to generate your own key and certificate:

1. Use the SPID compliant certificate builder

2. The above tool will create a PKCS#8 private key (key.pem) and a certificate (crt.pem). This package can handle RSA keys both in PKCS#8 and in PKCS#1 format. If you like to use the PKCS#1 format, we need to extract the RSA private key from the PKCS#8 file. In order to do this, we need to run this command:

   openssl rsa -in key.pem -out key.rsa.pem

Features

Compliance with SPID regulations (for Service Providers)
Metadata:
parsing of IdP XML metadata (1.2.2.4)	✓
support for multiple signing certificates in IdP XML metadata (1.2.2.4)	✓
parsing of AA XML metadata (2.2.4)
SP XML metadata generation (1.3.2)	✓
AuthnRequest generation (1.2.2.1):
generation of AuthnRequest XML	✓
HTTP-Redirect binding	✓
HTTP-POST binding	✓
AssertionConsumerServiceURL customization	✓
AssertionConsumerServiceIndex customization	✓
AttributeConsumingServiceIndex customization	✓
AuthnContextClassRef (SPID level) customization	✓
RequestedAuthnContext/@Comparison customization	✓
RelayState customization (1.2.2)	✓
Response/Assertion parsing
verification of Signature value (if any)	✓
verification of Signature certificate (if any) against IdP/AA metadata	✓
verification of Assertion/Signature value	✓
verification of Assertion/Signature certificate against IdP/AA metadata	✓
verification of SubjectConfirmationData/@Recipient	✓
verification of SubjectConfirmationData/@NotOnOrAfter	✓
verification of SubjectConfirmationData/@InResponseTo	✓
verification of Issuer	✓
verification of Assertion/Issuer	✓
verification of Destination	✓
verification of Conditions/@NotBefore	✓
verification of Conditions/@NotOnOrAfter	✓
verification of Audience	✓
parsing of Response with no Assertion (authentication/query failure)	✓
parsing of failure StatusCode (Requester/Responder)	✓
Response/Assertion parsing for SSO (1.2.1, 1.2.2.2, 1.3.1):
parsing of NameID	✓
parsing of AuthnContextClassRef (SPID level)	✓
parsing of attributes	✓
Response/Assertion parsing for attribute query (2.2.2.2, 2.3.1):
parsing of attributes
LogoutRequest generation (for SP-initiated logout):
generation of LogoutRequest XML	✓
HTTP-Redirect binding	✓
HTTP-POST binding	✓
LogoutResponse parsing (for SP-initiated logout):
parsing of LogoutResponse XML	✓
verification of Response/Signature value (if any)	✓
verification of Response/Signature certificate (if any) against IdP metadata	✓
verification of Issuer	✓
verification of Destination	✓
PartialLogout detection	✓
LogoutRequest parsing (for third-party-initiated logout):
parsing of LogoutRequest XML	✓
verification of Response/Signature value (if any)	✓
verification of Response/Signature certificate (if any) against IdP metadata	✓
verification of Issuer	✓
verification of Destination	✓
parsing of NameID	✓
LogoutResponse generation (for third-party-initiated logout):
generation of LogoutResponse XML	✓
HTTP-Redirect binding	✓
HTTP-POST binding	✓
PartialLogout customization	✓
AttributeQuery generation (2.2.2.1):
generation of AttributeQuery XML
SOAP binding (client)

Compliance with SPID regulations (for Attribute Authorities)
Metadata:
parsing of SP XML metadata (1.3.2)
AA XML metadata generation (2.2.4)
AttributeQuery parsing (2.2.2.1):
parsing of AttributeQuery XML
verification of Signature value
verification of Signature certificate against SP metadata
verification of Issuer
verification of Destination
parsing of Subject/NameID
parsing of requested attributes
Response/Assertion generation (2.2.2.2):
generation of Response/Assertion XML
Signature

More features

• Generation of SPID button markup

See also

• SPID page on Developers Italia

Authors

• Alessandro Ranellucci (maintainer) - Team per la Trasformazione Digitale - Presidenza del Consiglio dei Ministri
  • a.ranellucci@governo.it