SSO using OpenID Connect

.env.template

@@ -161,6 +161,10 @@
 ## Cron schedule of the job that cleans expired Duo contexts from the database. Does nothing if Duo MFA is disabled or set to use the legacy iframe prompt.
 ## Defaults to every minute. Set blank to disable this job.
 # DUO_CONTEXT_PURGE_SCHEDULE="30 * * * * *"
+#
+## Cron schedule of the job that cleans sso nonce from incomplete flow
+## Defaults to daily (20 minutes after midnight). Set blank to disable this job.
+# PURGE_INCOMPLETE_SSO_NONCE="0 20 0 * * *"
 
 ########################
 ### General settings ###
@@ -435,6 +439,42 @@
 ## Setting this to true will enforce the Single Org Policy to be enabled before you can enable the Reset Password policy.
 # ENFORCE_SINGLE_ORG_WITH_RESET_PW_POLICY=false
 
+#####################################
+### SSO settings (OpenID Connect) ###
+#####################################
+
+## Controls whether users can login using an OpenID Connect identity provider
+# SSO_ENABLED=false
+## Prevent users from logging in directly without going through SSO
+# SSO_ONLY=false
+## On SSO Signup if a user with a matching email already exists make the association
+# SSO_SIGNUPS_MATCH_EMAIL=true
+## Allow unknown email verification status. Allowing this with `SSO_SIGNUPS_MATCH_EMAIL=true` open potential account takeover.
+# SSO_ALLOW_UNKNOWN_EMAIL_VERIFICATION=false
+## Base URL of the OIDC server (auto-discovery is used)
+##  - Should not include the `/.well-known/openid-configuration` part and no trailing `/`
+##  - ${SSO_AUTHORITY}/.well-known/openid-configuration should return a json document: https://openid.net/specs/openid-connect-discovery-1_0.html#ProviderConfigurationResponse
+# SSO_AUTHORITY=https://auth.example.com
+## Authorization request scopes. Optional SSO scopes, override if email and profile are not enough (`openid` is implicit).
+#SSO_SCOPES="email profile"
+## Additionnal authorization url parameters (ex: to obtain a `refresh_token` with Google Auth).
+# SSO_AUTHORIZE_EXTRA_PARAMS="access_type=offline&prompt=consent"
+## Activate PKCE for the Auth Code flow.
+# SSO_PKCE=true
+## Regex to add additionnal trusted audience to Id Token (by default only the client_id is trusted).
+# SSO_AUDIENCE_TRUSTED='^$'
+## Set your Client ID and Client Key
+# SSO_CLIENT_ID=11111
+# SSO_CLIENT_SECRET=AAAAAAAAAAAAAAAAAAAAAAAA
+## Optional Master password policy (minComplexity=[0-4])
+# SSO_MASTER_PASSWORD_POLICY='{"enforceOnLogin":false,"minComplexity":3,"minLength":12,"requireLower":false,"requireNumbers":false,"requireSpecial":false,"requireUpper":false}'
+## Use sso only for authentication not the session lifecycle
+# SSO_AUTH_ONLY_NOT_SESSION=false
+## Client cache for discovery endpoint. Duration in seconds (0 to disable).
+# SSO_CLIENT_CACHE_EXPIRATION=0
+## Log all the tokens, LOG_LEVEL=debug is required
+# SSO_DEBUG_TOKENS=false
+
 ########################
 ### MFA/2FA settings ###
 ########################