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Authentication methods

Zulip supports a wide variety of authentication methods. Some of them require configuration to set up.

To configure or disable authentication methods on your Zulip server, edit the AUTHENTICATION_BACKENDS setting in /etc/zulip/settings.py, as well as any additional configuration your chosen authentication methods require; then restart the Zulip server.

Details on each method below.

Email and password

The EmailAuthBackend method is the one method enabled by default, and it requires no additional configuration.

Users set a password with the Zulip server, and log in with their email and password.

When first setting up your Zulip server, this method must be used for creating the initial realm and user. You can disable it after that.

Plug-and-play SSO (Google, GitHub, GitLab)

With just a few lines of configuration, your Zulip server can authenticate users with any of several single-sign-on (SSO) authentication providers:

Google accounts, with GoogleAuthBackend
GitHub accounts, with GitHubAuthBackend
GitLab accounts, with GitLabAuthBackend
Microsoft Azure Active Directory, with AzureADAuthBackend

Each of these requires one to a handful of lines of configuration in settings.py, as well as a secret in zulip-secrets.conf. Details are documented in your settings.py.

(ldap)=

LDAP (including Active Directory)

Zulip supports retrieving information about users via LDAP, and optionally using LDAP as an authentication mechanism.

In either configuration, you will need to do the following:

These instructions assume you have an installed Zulip server and are logged into a shell there. You can have created an organization already using EmailAuthBackend, or plan to create the organization using LDAP authentication.
Tell Zulip how to connect to your LDAP server:
- Fill out the section of your /etc/zulip/settings.py headed "LDAP integration, part 1: Connecting to the LDAP server".
- If a password is required, put it in /etc/zulip/zulip-secrets.conf by setting auth_ldap_bind_password. For example: auth_ldap_bind_password = abcd1234.
Decide how you want to map the information in your LDAP database to users' account data in Zulip. For each Zulip user, two closely related concepts are:
- their email address. Zulip needs this in order to send, for example, a notification when they're offline and another user sends a direct message.
- their Zulip username. This means the name the user types into the Zulip login form. You might choose for this to be the user's email address (sam@example.com), or look like a traditional "username" (sam), or be something else entirely, depending on your environment.
Either or both of these might be an attribute of the user records in your LDAP database.
Tell Zulip how to map the user information in your LDAP database to the form it needs for authentication. There are three supported ways to set up the username and/or email mapping:

(A) Using email addresses as Zulip usernames, if LDAP has each user's email address:
- Make AUTH_LDAP_USER_SEARCH a query by email address.
- Set AUTH_LDAP_REVERSE_EMAIL_SEARCH to the same query with %(email)s rather than %(user)s as the search parameter.
- Set AUTH_LDAP_USERNAME_ATTR to the name of the LDAP attribute for the user's LDAP username in the search result for AUTH_LDAP_REVERSE_EMAIL_SEARCH.
(B) Using LDAP usernames as Zulip usernames, with email addresses formed consistently like sam -> sam@example.com:
- Set AUTH_LDAP_USER_SEARCH to query by LDAP username
- Set LDAP_APPEND_DOMAIN = "example.com".
(C) Using LDAP usernames as Zulip usernames, with email addresses taken from some other attribute in LDAP (for example, mail):
- Set AUTH_LDAP_USER_SEARCH to query by LDAP username
- Set LDAP_EMAIL_ATTR = "mail".
- Set AUTH_LDAP_REVERSE_EMAIL_SEARCH to a query that will find an LDAP user given their email address (i.e. a search by LDAP_EMAIL_ATTR). For example:
```
AUTH_LDAP_REVERSE_EMAIL_SEARCH = LDAPSearch("ou=users,dc=example,dc=com",
                                            ldap.SCOPE_SUBTREE, "(mail=%(email)s)")
```
- Set AUTH_LDAP_USERNAME_ATTR to the name of the LDAP attribute for the user's LDAP username in that search result.

You can quickly test whether your configuration works by running:

/home/zulip/deployments/current/manage.py query_ldap username

from the root of your Zulip installation. If your configuration is working, that will output the full name for your user (and that user's email address, if it isn't the same as the "Zulip username").

Active Directory: Most Active Directory installations will use one of the following configurations:

To access by Active Directory username:

AUTH_LDAP_USER_SEARCH = LDAPSearch("ou=users,dc=example,dc=com",
                                   ldap.SCOPE_SUBTREE, "(sAMAccountName=%(user)s)")
AUTH_LDAP_REVERSE_EMAIL_SEARCH = LDAPSearch("ou=users,dc=example,dc=com",
                                   ldap.SCOPE_SUBTREE, "(mail=%(email)s)")
AUTH_LDAP_USERNAME_ATTR = "sAMAccountName"

To access by Active Directory email address:

AUTH_LDAP_USER_SEARCH = LDAPSearch("ou=users,dc=example,dc=com",
                                   ldap.SCOPE_SUBTREE, "(mail=%(user)s)")
AUTH_LDAP_REVERSE_EMAIL_SEARCH = LDAPSearch("ou=users,dc=example,dc=com",
                                            ldap.SCOPE_SUBTREE, "(mail=%(email)s)")
AUTH_LDAP_USERNAME_ATTR = "mail"

If you are using LDAP for authentication: you will need to enable the zproject.backends.ZulipLDAPAuthBackend auth backend, in AUTHENTICATION_BACKENDS in /etc/zulip/settings.py. After doing so (and as always restarting the Zulip server to ensure your settings changes take effect), you should be able to log in to Zulip by entering your email address and LDAP password on the Zulip login form.

You may also want to configure Zulip's settings for inviting new users. If LDAP is the only enabled authentication method, the main use case for Zulip's invitation feature is selecting the initial channels for invited users (invited users will still need to use their LDAP password to create an account).

Synchronizing data

Zulip can automatically synchronize data declared in AUTH_LDAP_USER_ATTR_MAP from LDAP into Zulip, via the following management command:

/home/zulip/deployments/current/manage.py sync_ldap_user_data

This will sync the fields declared in AUTH_LDAP_USER_ATTR_MAP for all of your users.

We recommend running this command in a regular cron job at whatever frequency your organization prefers for synchronizing changes made on your LDAP server to Zulip.

All of these data synchronization options have the same model:

New users will be populated automatically with the name/avatar/etc. from LDAP (as configured) on account creation.
manage.py sync_ldap_user_data will automatically update existing users with any changes that were made in LDAP.
You can easily test your configuration using manage.py query_ldap. Once you're happy with the configuration, remember to restart the Zulip server with /home/zulip/deployments/current/scripts/restart-server so that your configuration changes take effect.
Logs are available in /var/log/zulip/ldap.log.

When using this feature, you may also want to prevent users from changing their display name in the Zulip UI, since any such changes would be automatically overwritten on the sync run of manage.py sync_ldap_user_data.

Synchronizing avatars

Zulip supports syncing LDAP / Active Directory profile pictures (usually available in the thumbnailPhoto or jpegPhoto attribute in LDAP) by configuring the avatar key in AUTH_LDAP_USER_ATTR_MAP.

Synchronizing custom profile fields

Zulip supports syncing custom profile fields from LDAP / Active Directory. To configure this, you first need to configure some custom profile fields for your Zulip organization. Then, define a mapping from the fields you'd like to sync from LDAP to the corresponding LDAP attributes. For example, if you have a custom profile field LinkedIn Profile and the corresponding LDAP attribute is linkedinProfile then you just need to add 'custom_profile_field__linkedin_profile': 'linkedinProfile' to the AUTH_LDAP_USER_ATTR_MAP.

Synchronizing groups

Zulip supports syncing Zulip groups with LDAP groups. To configure this feature:

Review the django-auth-ldap documentation to determine which of its supported group type configurations matches how your LDAP directory stores groups.
Set AUTH_LDAP_GROUP_TYPE to the appropriate class instance for that LDAP group type:
```
from django_auth_ldap.config import ActiveDirectoryGroupType
AUTH_LDAP_GROUP_TYPE = ActiveDirectoryGroupType()
```
The default is GroupOfUniqueNamesType.

Configure AUTH_LDAP_GROUP_SEARCH to specify how to find groups in your LDAP directory:

AUTH_LDAP_GROUP_SEARCH = LDAPSearch(
    "ou=groups,dc=www,dc=example,dc=com", ldap.SCOPE_SUBTREE,
    "(objectClass=groupOfUniqueNames)"
)

Configure which LDAP groups you want to sync into Zulip. LDAP_SYNCHRONIZED_GROUPS_BY_REALM is a map where the keys are subdomains of the realms being configured (use "" for the root domain), and the value corresponding to the key being a list the names of groups to sync:
```
LDAP_SYNCHRONIZED_GROUPS_BY_REALM = {
  "subdomain1" : [
      "group1",
      "group2",
  ]
}
```
In this example configuration, for the Zulip realm with subdomain subdomain1, user membership in the Zulip groups named group1 and group2 will match their membership in LDAP groups with those names.
Test your configuration and restart the server into the new configuration as documented above.

Synchronizing email addresses

User accounts in Zulip are uniquely identified by their email address, and that's currently the only way through which a Zulip account is associated with their LDAP user account.

In particular, whenever a user attempts to log in to Zulip using LDAP, Zulip will use the LDAP information to authenticate the access, and determine the user's email address. It will then log in the user to the Zulip account with that email address (or if none exists, potentially prompt the user to create one). This model is convenient, because it works well with any LDAP provider (and handles migrations between LDAP providers transparently).

However, when a user's email address is changed in your LDAP directory, manual action needs to be taken to tell Zulip that the email address Zulip account with the new email address.

There are two ways to execute email address changes:

Users changing their email address in LDAP can change their email address in Zulip before logging out of Zulip. The user will need to be able to receive email at the new email address in order to complete this flow.
A server administrator can use the manage.py change_user_email management command to adjust a Zulip account's email address directly.

If a user accidentally creates a duplicate account, the duplicate account can be deactivated (and its email address changed) or deleted, and then the real account adjusted using the management command above.

Automatically deactivating users

Zulip supports synchronizing the disabled/deactivated status of users. If you're using Active Directory, you can configure this by uncommenting the sample line "userAccountControl": "userAccountControl", in AUTH_LDAP_USER_ATTR_MAP (and restarting the Zulip server). Zulip will then treat users that are disabled via the "Disable Account" feature in Active Directory as deactivated in Zulip.

If you're using a different LDAP server which uses a boolean attribute which is TRUE or YES for users that should be deactivated and FALSE or NO otherwise. You can configure a mapping for deactivated in AUTH_LDAP_USER_ATTR_MAP. For example, "deactivated": "nsAccountLock", is a correct mapping for a FreeIPA LDAP database.

Users who are disabled in LDAP will be immediately unable to log in to Zulip using LDAP authentication, since Zulip queries the LDAP/Active Directory server on every login attempt. The user will be fully deactivated the next time you run manage.py sync_ldap_user_data (at which point they will be forcibly logged out from all active browser sessions, appear as deactivated in the Zulip UI, etc.).

This feature works by checking for the ACCOUNTDISABLE flag on the userAccountControl field in Active Directory. See this handy resource for details on the various userAccountControl flags.

Deactivating non-matching users

Zulip supports automatically deactivating users if they are not found by the AUTH_LDAP_USER_SEARCH query (either because the user is no longer in LDAP/Active Directory, or because the user no longer matches the query). This feature is enabled by default if LDAP is the only authentication backend configured on the Zulip server. Otherwise, you can enable this feature by setting LDAP_DEACTIVATE_NON_MATCHING_USERS to True in /etc/zulip/settings.py. Nonmatching users will be fully deactivated the next time you run manage.py sync_ldap_user_data.

Other fields

Other fields you may want to sync from LDAP include:

Boolean flags describing the user's role / permission level: is_realm_owner (Organization owner), is_realm_admin (Organization administrator), is_guest (Guest), is_moderator (Moderator). You can use the AUTH_LDAP_USER_FLAGS_BY_GROUP feature of django-auth-ldap to configure a group to get any of these permissions. (Don't use this to modify other boolean flags such as is_active as that can introduce inconsistent state in the database; see the above discussion of automatic deactivation for how to do that properly).

Because the upstream django-auth-ldap library processes flags in the order they are listed in AUTH_LDAP_USER_FLAGS_BY_GROUP, flags should be listed in order from lowest to highest precedence (i.e., declare the is_guest group first and the is_realm_owner group last, if you'd like a user who is in both groups to be a realm owner rather than a guest).
String fields like default_language (e.g., en) or timezone, if you have that data in the right format in your LDAP database.

You can look at the full list of fields in the Zulip user model; search for class UserProfile, but the above should cover all the fields that would be useful to sync from your LDAP databases.

Multiple LDAP searches

To do the union of multiple LDAP searches, use LDAPSearchUnion. For example:

AUTH_LDAP_USER_SEARCH = LDAPSearchUnion(
    LDAPSearch("ou=users,dc=example,dc=com", ldap.SCOPE_SUBTREE, "(uid=%(user)s)"),
    LDAPSearch("ou=otherusers,dc=example,dc=com", ldap.SCOPE_SUBTREE, "(uid=%(user)s)"),
)

Restricting access to an LDAP group

You can restrict access to your Zulip server to a set of LDAP groups using the AUTH_LDAP_REQUIRE_GROUP and AUTH_LDAP_DENY_GROUP settings in /etc/zulip/settings.py.

An example configuration for Active Directory group restriction can be:

import django_auth_ldap
AUTH_LDAP_GROUP_TYPE = django_auth_ldap.config.ActiveDirectoryGroupType()

AUTH_LDAP_REQUIRE_GROUP = "cn=enabled,ou=groups,dc=example,dc=com"
AUTH_LDAP_GROUP_SEARCH = LDAPSearch("ou=groups,dc=example,dc=com", ldap.SCOPE_SUBTREE, "(objectClass=groupOfNames)")

Please note that AUTH_LDAP_GROUP_TYPE needs to be set to the correct group type for your LDAP server. See the upstream django-auth-ldap documentation for details.

Restricting LDAP user access to specific organizations

If you're hosting multiple Zulip organizations, you can restrict which users have access to which organizations. This is done by setting org_membership in AUTH_LDAP_USER_ATTR_MAP to the name of the LDAP attribute which will contain a list of subdomains that the user should be allowed to access.

For the root subdomain, www in the list will work, or any other of settings.ROOT_SUBDOMAIN_ALIASES.

For example, with org_membership set to department, a user with the following attributes will have access to the root and engineering subdomains:

...
department: engineering
department: www
...

More complex access control rules are possible via the AUTH_LDAP_ADVANCED_REALM_ACCESS_CONTROL setting. Note that org_membership takes precedence over AUTH_LDAP_ADVANCED_REALM_ACCESS_CONTROL:

If org_membership is set and allows access, access will be granted
If org_membership is not set or does not allow access, AUTH_LDAP_ADVANCED_REALM_ACCESS_CONTROL will control access.

AUTH_LDAP_ADVANCED_REALM_ACCESS_CONTROL is a dictionary keyed by the organization's subdomain. The corresponding value is a list of attribute: value pair sets such that a user is permitted to access the organization if and only if the attribute: value pairs in at least one of these sets match the user's LDAP attributes. If this setting is enabled, organizations not explicitly configured in it will not be affected - they'll allow normal LDAP login, unless restricted by other settings. This is better illustrated with an example:

AUTH_LDAP_ADVANCED_REALM_ACCESS_CONTROL = {
    "zulip": [
        {
            "department": "main",
            "employeeType": "staff"
        },
        {
            "office": "Dallas"
        }
    ]
}

This means that the organization "zulip" will be accessible via ldap authentication only for users whose ldap attributes either contain both department: main employeeType: staff or just office: Dallas. LDAP authentication will proceed normally for all other organizations.

:::{warning} Restricting access using these mechanisms only affects authentication via LDAP, and won't prevent users from accessing the organization using any other authentication backends that are enabled for the organization. :::

Troubleshooting

Most issues with LDAP authentication are caused by misconfigurations of the user and email search settings. Some things you can try to get to the bottom of the problem:

Review the instructions for the LDAP configuration type you're using: (A), (B) or (C) (described above), and that you have configured all of the required settings documented in the instructions for that configuration type.
Use the manage.py query_ldap tool to verify your configuration. The output of the command will usually indicate the cause of any configuration problem. For the LDAP integration to work, this command should be able to successfully fetch a complete, correct set of data for the queried user.
You can find LDAP-specific logs in /var/log/zulip/ldap.log. If you're asking for help with your setup, please provide logs from this file (feel free to anonymize any email addresses to username@example.com) in your report.

SAML

Zulip supports SAML authentication, used by Okta, OneLogin, and many other IdPs (identity providers). You can configure it as follows:

These instructions assume you have an installed Zulip server; if you're using Zulip Cloud, see this article, which also has IdP-side configuration advice for common IdPs.

You can have created a Zulip organization already using the default EmailAuthBackend, or plan to create the organization using SAML authentication.
Tell your IdP how to find your Zulip server:
- SP Entity ID: https://yourzulipdomain.example.com.
  
  The Entity ID should match the value of SOCIAL_AUTH_SAML_SP_ENTITY_ID computed in the Zulip settings. You can get the correct value by running the following: /home/zulip/deployments/current/scripts/get-django-setting SOCIAL_AUTH_SAML_SP_ENTITY_ID.
- SSO URL: https://yourzulipdomain.example.com/complete/saml/. This is the "SAML ACS url" in SAML terminology.
  
  If you're hosting multiple organizations, you need to use SOCIAL_AUTH_SUBDOMAIN. For example, if SOCIAL_AUTH_SUBDOMAIN="auth" and EXTERNAL_HOST=zulip.example.com, this should be https://auth.zulip.example.com/complete/saml/.
Tell Zulip how to connect to your SAML provider(s) by filling out the section of /etc/zulip/settings.py on your Zulip server with the heading "SAML Authentication".
- You will need to update SOCIAL_AUTH_SAML_ORG_INFO with your organization name (displayname may appear in the IdP's authentication flow; name won't be displayed to humans).
- Fill out SOCIAL_AUTH_SAML_ENABLED_IDPS with data provided by your identity provider. You may find the python-social-auth SAML docs helpful. You'll need to obtain several values from your IdP's metadata and enter them on the right-hand side of this Python dictionary:
  1. Set the outer idp_name key to be an identifier for your IdP, e.g., testshib or okta. This field appears in URLs for parts of your Zulip server's SAML authentication flow.
  2. The IdP should provide the url and entity_id values.
  3. Save the x509cert value to a file; you'll use it in the instructions below.
  4. The values needed in the attr_ fields are often configurable in your IdP's interface when setting up SAML authentication (referred to as "Attribute Statements" with Okta, or "Attribute Mapping" with Google Workspace). You'll want to connect these so that Zulip gets the email address (used as a unique user ID) and name for the user.
  5. The display_name and display_icon fields are used to display the login/registration buttons for the IdP.
  6. The auto_signup field determines how Zulip should handle login attempts by users who don't have an account yet.
Install the certificate(s) required for SAML authentication. You will definitely need the public certificate of your IdP. Some IdP providers also support the Zulip server (Service Provider) having a certificate used for encryption and signing. We detail these steps as optional below, because they aren't required for basic setup, and some IdPs like Okta don't fully support Service Provider certificates. You should install them as follows:
1. On your Zulip server, mkdir -p /etc/zulip/saml/idps/
2. Put the IDP public certificate in /etc/zulip/saml/idps/{idp_name}.crt
3. (Optional) Put the Zulip server public certificate in /etc/zulip/saml/zulip-cert.crt and the corresponding private key in /etc/zulip/saml/zulip-private-key.key. Note that the certificate should be the single X.509 certificate for the server, not a full chain of trust, which consists of multiple certificates. The private key cannot be encrypted with a password, as then Zulip will not be able to load it. An example pair can be generated using:
```
openssl req -x509 -newkey rsa:2056 -keyout zulip-private-key.key -out zulip-cert.crt -days 365 -nodes
```
4. Set the proper permissions on these files and directories:
```
chown -R zulip.zulip /etc/zulip/saml/
find /etc/zulip/saml/ -type f -exec chmod 644 -- {} +
chmod 640 /etc/zulip/saml/zulip-private-key.key
```
(Optional) If you configured the optional public and private server certificates above, you can enable the additional setting "authnRequestsSigned": True in SOCIAL_AUTH_SAML_SECURITY_CONFIG to have the SAMLRequests the server will be issuing to the IdP signed using those certificates. Additionally, if the IdP supports it, you can upload the public certificate to enable encryption of assertions in the SAMLResponses the IdP will send about authenticated users.
Enable the zproject.backends.SAMLAuthBackend auth backend, in AUTHENTICATION_BACKENDS in /etc/zulip/settings.py.
Restart the Zulip server to ensure your settings changes take effect. The Zulip login page should now have a button for SAML authentication that you can use to log in or create an account (including when creating a new organization).
If the configuration was successful, the server's metadata can be found at https://yourzulipdomain.example.com/saml/metadata.xml. You can use this for verifying your configuration or provide it to your IdP.

IdP-initiated SSO

The above configuration is sufficient for Service Provider initialized SSO, i.e. you can visit the Zulip web app and click "Sign in with {IdP}" and it'll correctly start the authentication flow. If you are not hosting multiple organizations, the above configuration is also sufficient for Identity Provider initiated SSO, i.e. clicking a "Sign in to Zulip" button on the IdP's website can correctly authenticate the user to Zulip.

If you're hosting multiple organizations and thus using the SOCIAL_AUTH_SUBDOMAIN setting, you'll need to configure a custom RelayState in your IdP of the form {"subdomain": "yourzuliporganization"} to let Zulip know which organization to authenticate the user to when they visit your SSO URL from the IdP. (If the organization is on the root domain, use the empty string: {"subdomain": ""}.).

Restricting access to specific organizations

If you're hosting multiple Zulip organizations, you can restrict which organizations can use a given IdP by setting limit_to_subdomains. For example, limit_to_subdomains = ["", "engineering"] would restrict an IdP the root domain and the engineering subdomain.

You can achieve the same goal with a SAML attribute; just declare which attribute using attr_org_membership in the IdP configuration. For the root subdomain, www in the list will work, or any other of settings.ROOT_SUBDOMAIN_ALIASES.

For example, with attr_org_membership set to member, a user with the following attribute in their AttributeStatement will have access to the root and engineering subdomains:

<saml2:Attribute Name="member" NameFormat="urn:oasis:names:tc:SAML:2.0:attrname-format:unspecified">
  <saml2:AttributeValue xmlns:xs="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:type="xs:string">
    www
  </saml2:AttributeValue>
  <saml2:AttributeValue xmlns:xs="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:type="xs:string">
    engineering
  </saml2:AttributeValue>
</saml2:Attribute>

In contrast with SCIM or LDAP, the SAML protocol only allows Zulip to access data about a user when that user authenticates to Zulip using SAML, so metadata can only be synchronized when the user logs in.

As a result, most installations using SAML will want to use SCIM provisioning to synchronize metadata continuously. Zulip nonetheless includes support for copying certain fields from a SAML database, which can be a good option when a SAML provider does not offer SCIM or the fields one is interested in syncing change rarely enough that asking users to logout and then login again to resync their metadata might feel reasonable.

Specifically, Zulip supports synchronizing the user role and custom profile fields from the SAML provider.

In order to use this functionality, configure SOCIAL_AUTH_SYNC_ATTRS_DICT in /etc/zulip/settings.py according to the instructions in the inline documentation in the file. Servers installed before Zulip 10.0 may want to update inline comment documentation first in order to access it.

Custom profile fields are only synchronized during login, not during account creation; we consider this a bug. User role is synchronized during both account creation and each consecutive login.

:::{note} When user role is provided by the SAML IdP during signup of a user who's coming from an invitation link, the IdP-provided role will take precedence over the role set in the invitation. :::

SCIM

Many SAML IdPs also offer SCIM provisioning to manage automatically deactivating accounts; consider configuring the Zulip SCIM integration.

Using Keycloak as a SAML IdP

Make sure you reviewed this article, which details how to configure Keycloak properly to use SAML with Zulip.
Verify that SOCIAL_AUTH_SAML_ENABLED_IDPS[{idp_name}]['entity_id'] and SOCIAL_AUTH_SAML_ENABLED_IDPS[{idp_name}]['url'] are correct in your Zulip configuration. Specifically, if entity_id is https://keycloak.example.com/auth/realms/master, then url should be https://keycloak.example.com/auth/realms/master/protocol/saml
Your Keycloak public certificate must be saved on the Zulip server as {idp_name}.crt in /etc/zulip/saml/idps/. You can obtain the certificate from the Keycloak UI in the Keys tab. Click on the button Certificate and copy the content.

(Alternatively, open the URL in your browser https://keycloak.example.com/auth/realms/master/protocol/saml/descriptor. Replace the domain (keycloak.example.com) as well as the realm name (master) in the url. Note that depending on your version of Keycloak, /auth/ may or may not be present in the URL. The certificate is the content inside <ds:X509Certificate>[...]</ds:X509Certificate>).

Save the certificate in a new {idp_name}.crt file constructed as follows:
```
-----BEGIN CERTIFICATE-----
{Paste the content here}
-----END CERTIFICATE-----
```
If you want to sign SAML requests, you have to do two things in Keycloak:
1. In the Keycloak client settings you set up previously, open the Settings tab and enable Client Signature Required.
2. Keycloak can generate the Client private key and certificate automatically, but Zulip's SAML library does not support the resulting certificates. Instead, you must generate the key and certificate on the Zulip server and import them into Keycloak:
  1. Generate Zulip server public certificate and the corresponding private key:
```
openssl req -x509 -newkey rsa:2056 -keyout zulip-private-key.key \
  -out zulip-cert.crt -days 365 -nodes
```
  2. Generate a JKS keystore (replace {mypassword} and {myalias} in the keytool invocation):
```
openssl pkcs12 -export -out domainname.pfx -inkey zulip-private-key.key -in zulip-cert.crt
keytool -importkeystore -srckeystore domainname.pfx -srcstoretype pkcs12 \
  -srcalias 1 -srcstorepass {mypassword} -destkeystore domainname.jks \
  -deststoretype jks -destalias {myalias}
```
    You can run the above on the Zulip server. If you instead run it on a Mac, you may want to use the keychain administration tool to generate the JKS keystore with a UI instead of using the keytool command. (see also: https://stackoverflow.com/a/41250334)
  3. Then switch to the SAML Keys tab of your Keycloak client. Import domainname.pfx into Keycloak. After importing, only the certificate will be displayed (not the private key).

Using Authentik as a SAML IdP

Make sure you reviewed this article, which details how to integrate Zulip with Authentik.
Verify that SOCIAL_AUTH_SAML_ENABLED_IDPS[{idp_name}]['entity_id'] and SOCIAL_AUTH_SAML_ENABLED_IDPS[{idp_name}]['url'] are correct in your Zulip configuration. Specifically, if entity_id is https://authentik.example.com/, then url should be https://authentik.company/application/saml/<application slug>/sso/binding/redirect/ where <application slug> is the application slug you've assigned to this application in Authentik settings (e.g zulip).

Update the attribute mapping in your new entry in SOCIAL_AUTH_SAML_ENABLED_IDPS to match how Authentik specifies attributes in its SAMLResponse:

"attr_user_permanent_id": "http://schemas.xmlsoap.org/ws/2005/05/identity/claims/emailaddress",
"attr_first_name": "http://schemas.xmlsoap.org/ws/2005/05/identity/claims/name",
"attr_last_name": "http://schemas.xmlsoap.org/ws/2005/05/identity/claims/name",
"attr_username": "http://schemas.xmlsoap.org/ws/2005/05/identity/claims/emailaddress",
"attr_email": "http://schemas.xmlsoap.org/ws/2005/05/identity/claims/emailaddress",

Your Authentik public certificate must be saved on the Zulip server as /etc/zulip/saml/idps/{idp_name}.crt. You can obtain the certificate from the Authentik UI in the Certificates section or directly from the provider's page.

(Alternatively, open the settings page of the provider you created and copy the certificate embedded in the SAML Metadata's <ds:X509Certificate> field.).

Save the certificate in a new {idp_name}.crt file constructed as follows:
```
-----BEGIN CERTIFICATE-----
{Paste the content here}
-----END CERTIFICATE-----
```

SAML Single Logout

Zulip supports both IdP-initiated and SP-initiated SAML Single Logout. The implementation has primarily been tested with Keycloak and these instructions are for that provider; please contact us if you need help using this with another IdP.

IdP-initiated Single Logout

In the KeyCloak configuration for Zulip, enable Force Name ID Format and set Name ID Format to email. Zulip needs to receive the user's email address in the NameID to know which user's sessions to terminate.
Make sure Front Channel Logout is enabled, which it should be by default. Disable Force POST Binding, as Zulip only supports the Redirect binding.
In Fine Grain SAML Endpoint Configuration, set Logout Service Redirect Binding URL to the same value you provided for SSO URL above.
Add the IdP's Redirect Binding URL for SingleLogoutService to your IdP configuration dict in SOCIAL_AUTH_SAML_ENABLED_IDPS in /etc/zulip/settings.py as slo_url. For example it may look like this:
```
"your_keycloak_idp_name": {
    "entity_id": "https://keycloak.example.com/auth/realms/yourrealm",
    "url": "https://keycloak.example.com/auth/realms/yourrealm/protocol/saml",
    "slo_url": "https://keycloak.example.com/auth/realms/yourrealm/protocol/saml",
    ...
```
You can find these details in your SAML 2.0 Identity Provider Metadata (available in your Realm Settings).
Because Keycloak uses the old Name ID Format format for pre-existing sessions, each user needs to be logged out before SAML Logout will work for them. Test SAML logout with your account by logging out from Zulip, logging back in using SAML, and then using the SAML logout feature from KeyCloak. Check /var/log/zulip/errors.log for error output if it doesn't work.
Once SAML logout is working for you, you can use the manage.py logout_all_users management command to log out all users so that SAML logout works for everyone.
```
/home/zulip/deployments/current/manage.py logout_all_users
```

SP-initiated Single Logout

After configuring IdP-initiated Logout, you only need to set "sp_initiated_logout_enabled": True in the appropriate IdP configuration dict in SOCIAL_AUTH_SAML_ENABLED_IDPS in /etc/zulip/settings.py to also enable SP-initiated Logout. When this is active, a user who logged in to Zulip via SAML, upon clicking "Logout" in the Zulip web app will be redirected to the IdP's Single Logout endpoint with a LogoutRequest. If a successful LogoutResponse is received back, their current Zulip session will be terminated.

Note that this doesn't work when logging out of the mobile application since the app doesn't use sessions and relies on just having the user's API key.

Caveats

This implementation doesn't support using SessionIndex to limit which sessions are affected; in IdP-initiated Logout it always terminates all logged-in sessions for the user identified in the NameID.
SAML Logout in a configuration where your IdP handles authentication for multiple organizations is not yet supported.

Apache-based SSO with `REMOTE_USER`

If you have any existing SSO solution where a preferred way to deploy it (a) runs inside Apache, and (b) sets the REMOTE_USER environment variable, then the ZulipRemoteUserBackend method provides you with a straightforward way to deploy that SSO solution with Zulip.

Setup instructions for Apache-based SSO

In /etc/zulip/settings.py, configure two settings:
- AUTHENTICATION_BACKENDS: 'zproject.backends.ZulipRemoteUserBackend', and no other entries.
- SSO_APPEND_DOMAIN: see documentation in settings.py.
Make sure that you've restarted the Zulip server since making this configuration change.

Edit /etc/zulip/zulip.conf and change the puppet_classes line to read:

puppet_classes = zulip::profile::standalone, zulip::apache_sso

As root, run /home/zulip/deployments/current/scripts/zulip-puppet-apply to install our SSO integration.
To configure our SSO integration, edit a copy of /etc/apache2/sites-available/zulip-sso.example, saving the result as /etc/apache2/sites-available/zulip-sso.conf. The example sets up HTTP basic auth, with an htpasswd file; you'll want to replace that with configuration for your SSO solution to authenticate the user and set REMOTE_USER.

For testing, you may want to move ahead with the rest of the setup using the htpasswd example configuration and demonstrate that working end-to-end, before returning later to configure your SSO solution. You can do that with the following steps:
```
/home/zulip/deployments/current/scripts/restart-server
cd /etc/apache2/sites-available/
cp zulip-sso.example zulip-sso.conf
htpasswd -c /home/zulip/zpasswd username@example.com # prompts for a password
```
Run a2ensite zulip-sso to enable the SSO integration within Apache.
Run service apache2 reload to use your new configuration. If Apache isn't already running, you may need to run service apache2 start instead.

Now you should be able to visit your Zulip server in a browser (e.g., at https://zulip.example.com/) and log in via the SSO solution.

Troubleshooting Apache-based SSO

Most issues with this setup tend to be subtle issues with the hostname/DNS side of the configuration. Suggestions for how to improve this SSO setup documentation are very welcome!

For example, common issues have to do with /etc/hosts not mapping settings.EXTERNAL_HOST to the Apache listening on 127.0.0.1/localhost.
While debugging, it can often help to temporarily change the Apache config in /etc/apache2/sites-available/zulip-sso to listen on all interfaces rather than just 127.0.0.1.
While debugging, it can also be helpful to change proxy_pass in /etc/nginx/zulip-include/app.d/external-sso.conf to point to a more explicit URL, possibly not over HTTPS.
The following log files can be helpful when debugging this setup:
- /var/log/zulip/{errors.log,server.log} (the usual places)
- /var/log/nginx/access.log (nginx access logs)
- /var/log/apache2/zulip_auth_access.log (from the zulip-sso.conf Apache config file; you may want to change LogLevel in that file to "debug" to make this more verbose)

Here's a summary of how the Apache REMOTE_USER SSO system works, assuming you're using the example configuration with HTTP basic auth. This summary should help with understanding what's going on as you try to debug.

Since you've configured /etc/zulip/settings.py to only define the zproject.backends.ZulipRemoteUserBackend, zproject/computed_settings.py configures /accounts/login/sso/ as HOME_NOT_LOGGED_IN. This makes https://zulip.example.com/ (a.k.a. the homepage for the main Zulip Django app running behind nginx) redirect to /accounts/login/sso/ for a user that isn't logged in.
nginx proxies requests to /accounts/login/sso/ to an Apache instance listening on localhost:8888, via the config in /etc/nginx/zulip-include/app.d/external-sso.conf (using the upstream localhost_sso, defined in /etc/nginx/zulip-include/upstreams).
The Apache zulip-sso site which you've enabled listens on localhost:8888 and (in the example config) presents the htpasswd dialogue. (In a real configuration, it takes the user through whatever more complex interaction your SSO solution performs.) The user provides correct login information, and the request reaches a second Zulip Django app instance, running behind Apache, with REMOTE_USER set. That request is served by zerver.views.remote_user_sso, which just checks the REMOTE_USER variable and either logs the user in or, if they don't have an account already, registers them. The login sets a cookie.
After succeeding, that redirects the user back to / on port 443. This request is sent by nginx to the main Zulip Django app, which sees the cookie, treats them as logged in, and proceeds to serve them the main app page normally.

Zulip supports using the web flow for Sign in with Apple on self-hosted servers. To do so, you'll need to do the following:

Visit the Apple Developer site and Create a Services ID.. When prompted for a "Return URL", enter https://zulip.example.com/complete/apple/ (using the domain for your server).
Create a Sign in with Apple private key.
Store the resulting private key at /etc/zulip/apple-auth-key.p8. Be sure to set permissions correctly:
```
chown zulip:zulip /etc/zulip/apple-auth-key.p8
chmod 640 /etc/zulip/apple-auth-key.p8
```
Configure Apple authentication in /etc/zulip/settings.py:
- SOCIAL_AUTH_APPLE_TEAM: Your Team ID from Apple, which is a string like "A1B2C3D4E5".
- SOCIAL_AUTH_APPLE_SERVICES_ID: The Services ID you created in step 1, which might look like "com.example.services".
- SOCIAL_AUTH_APPLE_APP_ID: The App ID, or Bundle ID, of your app that you used in step 1 to configure your Services ID. This might look like "com.example.app".
- SOCIAL_AUTH_APPLE_KEY: Despite the name this is not a key, but rather the Key ID of the key you created in step 2. This looks like "F6G7H8I9J0".
- AUTHENTICATION_BACKENDS: Uncomment (or add) a line like 'zproject.backends.AppleAuthBackend', to enable Apple auth using the created configuration.
Register with Apple the email addresses or domains your Zulip server sends email to users from. For instructions and background, see the "Email Relay Service" subsection of this page. For details on what email addresses Zulip sends from, see our outgoing email documentation.

OpenID Connect

Zulip can be integrated with any OpenID Connect (OIDC) authentication provider. You can configure it by enabling zproject.backends.GenericOpenIdConnectBackend in AUTHENTICATION_BACKENDS and following the steps outlined in the comment documentation in /etc/zulip/settings.py.

If your server was originally installed from a release in the 4.x series or earlier, you will need to update your settings.py file. You can find instructions on how to do that in a separate doc.

Note that SOCIAL_AUTH_OIDC_ENABLED_IDPS only supports a single IdP currently.

The Return URL to authorize with the provider is https://yourzulipdomain.example.com/complete/oidc/.

By default, users who attempt to log in with OIDC using an email address that does not have a current Zulip account will be prompted for whether they intend to create a new account or would like to log in using another authentication method. You can configure automatic account creation on first login attempt by setting "auto_signup": True in the IdP configuration dictionary.

The global setting SOCIAL_AUTH_OIDC_FULL_NAME_VALIDATED controls how Zulip uses the Full Name provided by the IdP. By default, Zulip prefills that value in the new account creation form, but gives the user the opportunity to edit it before submitting. When True, Zulip assumes the name is correct, and new users will not be presented with a registration form unless they need to accept Terms of Service for the server (i.e. TERMS_OF_SERVICE_VERSION is set).

JWT

Zulip supports using JSON Web Tokens (JWT) authentication in two ways:

Obtaining a logged in session by making a POST request to /accounts/login/jwt/. This allows a separate application to integrate with Zulip via having a button that directly takes the user to Zulip and logs them in.
Fetching a user's API key by making a POST request to /api/v1/jwt/fetch_api_key. This allows a separate application to integrate with Zulip by making API requests on behalf of any user in a Zulip organization.

In both cases, the request should be made by sending an HTTP POST request with the JWT in the token parameter, with the JWT payload having the structure {"email": "<target user email>"}.

In order to use JWT authentication with Zulip, one must first configure the JWT secret and algorithm via JWT_AUTH_KEYS in /etc/zulip/settings.py; see the inline comment documentation in that file for details.

Configuring a custom Python wrapper around the `authenticate` mechanism

Zulip supports configuring a custom authentication function that will work as a wrapper around every login attempt to Zulip, enabling custom logging, additional authentication checks, and more.

This mechanism protects the web login and the mobile login process used to obtain an API key, but will not be called when processing API requests by the Zulip mobile apps or other API clients that have already obtained an API key (a step that typically happens once per device during first-time login).

:::{note} Knowledge of how authentication backends work in Django as well as some familiarity with Zulip's authentication implementation in zproject/backends.py are required.

This feature is beta and has some rough edges as well as requiring significantly more expertise than other authentication features; we do not recommend using it without specific advice from Zulip support, but we document it here for completeness. :::

You can write custom Python logic that will wrap such authenticate() calls by specifying in /etc/zulip/settings.py:

def custom_auth_wrapper(
    auth_func, *args, **kwargs
):
    from zerver.lib.exceptions import JsonableError

    backend = args[0]
    backend_name = backend.name
    request = args[1]
    ip_address = request.META["REMOTE_ADDR"]
    backend.logger.info("%s backend. ip is %s", backend_name, ip_address)

    user_profile = auth_func(*args, **kwargs)
    if user_profile is not None and user_profile.delivery_email == "protecteduser@example.com":
        if backend_name == "email" and ip_address != "x.x.x.x":
            raise JsonableError("Your IP address is not allowed to log in as this user.")

    return user_profile

# We need to actually specify to use this function defined above as the
# custom authentication wrapper:
CUSTOM_AUTHENTICATION_WRAPPER_FUNCTION = custom_auth_wrapper

auth_func is the underlying authenticate function belonging to the authentication backend class currently being processed. If you have more than one backend enabled, this will be executed multiple times - each time with auth_func being the authenticate function of the backend class currently being processed.

Therefore, your custom_auth_wrapper can inspect the received arguments, process them as desired and eventually call the original auth_func to obtain the underlying authentication result, to analyze and potentially return it. The simple code demonstrated above checks whether auth_func succeeds, and if so, whether the resulting user account belongs to protecteduser@example.com. Such authentication, if it's using the EmailAuthBackend should only be allowed if made from a pre-defined IP address x.x.x.x, so if these restrictions are violated, a JSON error response will be generated.

The example demonstrates the possibility of making the logic dependent on the specific authentication backend being used, but unless you're very familiar with the various backends used by Zulip, a safer approach is to keep things general.

:::{important}

Using CUSTOM_AUTHENTICATION_WRAPPER_FUNCTION with social authentication backends (Google, GitHub, and anything else that subclasses SocialAuthMixin in zproject/backends.py) is not recommended.

Due to the different way that social authentication backends process authentication attempts using a 3rd party site that provides the user's identity, it is not a good approach to modify their own authenticate calls directly.

If you need to use this feature in combination with those backends, you should make your logic be applied when processing the ZulipDummyBackend - which is the final layer of the authentication checks for whether authentication should succeed. If you want to reject authentication requests (e.g., based on IP address of the request), this is where it should happen. :::

Adding more authentication backends

Adding an integration with any of the more than 100 authentication providers supported by python-social-auth (e.g., Facebook, Twitter, etc.) is easy to do if you're willing to write a bit of code, and pull requests to add new backends are welcome.

For example, the Azure Active Directory integration was about 30 lines of code, plus some documentation and an automatically generated migration. We also have helpful developer documentation on testing auth backends.

Development only

The DevAuthBackend method is used only in development, to allow passwordless login as any user in a development environment. It's mentioned on this page only for completeness.

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