[Bug] OIDC users don't always get a username

[ToxicMushroom]

Is this a support request?

• This is not a support request

Is there an existing issue for this?

• I have searched the existing issues

Current Behavior

When logging in for the first time with oidc I only got a display_name and no username/name set in headscale.

This can be worked around currently by docker exec headscale headscale users rename --identifier 1 -r merlijn
But that'd be inconvenient for future users so it should probably get resolved.

Expected Behavior

All the required user fields get set when logging in with oidc,

• either by requiring certain claims are present in the idToken.
• or by making the cli commands more flexible: by accepting user ids as an alternative.

Steps To Reproduce

1. Setup OIDC (can see my config below)
2. Authenticate new user (My oidc resource server is ran on Kanidm, returned claims are also below)
3. List the user's fields (also below)

Environment

- OS: Debian 12
- Headscale version: ghcr.io/juanfont/headscale:0.24.0-beta.2-debug
- Tailscale version: 1.78.1

Runtime environment

• Headscale is behind a (reverse) proxy
• Headscale runs in a container

Anything else?

root@zungenbrecher:/opt/vpn_exit_node# docker exec headscale headscale users list -o json

[
    {
        "id": 1,
        "created_at": {
            "seconds": 1735582411,
            "nanos": 102993003
        },
        "display_name": "Merlijn",
        "provider_id": "oauth2urlthing",
        "provider": "oidc"
    }
]

oidc claims for my user with "profile", "email", "groups" scopes

claims: {
    "sub": "2fa57e05-fcc9-43db-8ca6-a98602346aa5",
    "exp": 1736341021,
    "name": "Merlijn",
    "preferred_username": "[email protected]",
    "groups": [
        "[email protected]",
        "00000000-0000-0000-0000-000000000035",
        "[email protected]",
        "00000000-0000-0000-0000-000000000036",
        "[email protected]",
        "91f2f258-3122-4644-a860-cbfe2cce5b73",
        "[email protected]",
        "1163f5cc-6dee-46c8-85db-fd635247c9bd",
        "[email protected]",
        "553b933b-0f01-432d-88a8-d69b182c4cf6",
        "[email protected]",
        "77b999f8-cd55-4a71-8133-ee9ec674e02f",
        "[email protected]",
        "ef5a6995-759f-48fa-a4cf-262506f7712e",
        "[email protected]",
        "f5c60e0c-0562-438e-908b-f6182a9e1651",
        "[email protected]",
        "844abd6f-f2d9-4b61-9bec-6625e6cb3501",
        "[email protected]",
        "4bc73263-b472-4fa8-87fe-ba3c5ffe2841",
        "[email protected]",
        "432f03b2-260a-4c16-8588-5fdabf805c01",
        "[email protected]",
        "8141a6e0-0f66-4a3d-b287-550b5e4477dd",
        "[email protected]",
        "d827b7e0-2a54-41a8-bb30-4fada22b9c4d",
        "[email protected]",
        "185f75f5-6527-47be-8058-9cf0978aa63f",
        "[email protected]",
        "dbcb4f90-5451-4967-86f6-5faa2f94670b",
        "[email protected]",
        "cbcb7793-f25b-48a1-93e2-d9593b70a151",
        "[email protected]",
        "292b042d-84db-4541-8f3c-465394efaae7",
        "[email protected]",
        "89239a93-efc6-4cca-bbfe-f1ba1bdf547f",
        "[email protected]",
        "00000000-0000-0000-0000-000000000048",
        "[email protected]",
        "b0b1647e-a4d5-4e25-a211-3824e06fae8b",
        "[email protected]",
        "b367fe8e-2041-47ee-abec-af5a2fb230fb"
    ],
    "email": "redacted against spam bots",
    "email_verified": true
}

config.yaml

---
# headscale will look for a configuration file named `config.yaml` (or `config.json`) in the following order:
#
# - `/etc/headscale`
# - `~/.headscale`
# - current working directory

# The url clients will connect to.
# Typically this will be a domain like:
#
# https://myheadscale.example.com:443
#
server_url: https://headscale.example.com

# Address to listen to / bind to on the server
#
# For production:
# listen_addr: 0.0.0.0:8080
listen_addr: 0.0.0.0:8080

# Address to listen to /metrics, you may want
# to keep this endpoint private to your internal
# network
#
metrics_listen_addr: 127.0.0.1:9090

# Address to listen for gRPC.
# gRPC is used for controlling a headscale server
# remotely with the CLI
# Note: Remote access _only_ works if you have
# valid certificates.
#
# For production:
# grpc_listen_addr: 0.0.0.0:50443
grpc_listen_addr: 127.0.0.1:50443

# Allow the gRPC admin interface to run in INSECURE
# mode. This is not recommended as the traffic will
# be unencrypted. Only enable if you know what you
# are doing.
grpc_allow_insecure: false

# The Noise section includes specific configuration for the
# TS2021 Noise protocol
noise:
  # The Noise private key is used to encrypt the
  # traffic between headscale and Tailscale clients when
  # using the new Noise-based protocol.
  private_key_path: /var/lib/headscale/noise_private.key

# List of IP prefixes to allocate tailaddresses from.
# Each prefix consists of either an IPv4 or IPv6 address,
# and the associated prefix length, delimited by a slash.
# It must be within IP ranges supported by the Tailscale
# client - i.e., subnets of 100.64.0.0/10 and fd7a:115c:a1e0::/48.
# See below:
# IPv6: https://github.com/tailscale/tailscale/blob/22ebb25e833264f58d7c3f534a8b166894a89536/net/tsaddr/tsaddr.go#LL81C52-L81C71
# IPv4: https://github.com/tailscale/tailscale/blob/22ebb25e833264f58d7c3f534a8b166894a89536/net/tsaddr/tsaddr.go#L33
# Any other range is NOT supported, and it will cause unexpected issues.
prefixes:
  v4: 100.64.0.0/10
  v6: fd7a:115c:a1e0::/48

  # Strategy used for allocation of IPs to nodes, available options:
  # - sequential (default): assigns the next free IP from the previous given IP.
  # - random: assigns the next free IP from a pseudo-random IP generator (crypto/rand).
  allocation: sequential

# DERP is a relay system that Tailscale uses when a direct
# connection cannot be established.
# https://tailscale.com/blog/how-tailscale-works/#encrypted-tcp-relays-derp
#
# headscale needs a list of DERP servers that can be presented
# to the clients.
derp:
  server:
    # If enabled, runs the embedded DERP server and merges it into the rest of the DERP config
    # The Headscale server_url defined above MUST be using https, DERP requires TLS to be in place
    enabled: false

    # Region ID to use for the embedded DERP server.
    # The local DERP prevails if the region ID collides with other region ID coming from
    # the regular DERP config.
    region_id: 999

    # Region code and name are displayed in the Tailscale UI to identify a DERP region
    region_code: "headscale"
    region_name: "Headscale Embedded DERP"

    # Listens over UDP at the configured address for STUN connections - to help with NAT traversal.
    # When the embedded DERP server is enabled stun_listen_addr MUST be defined.
    #
    # For more details on how this works, check this great article: https://tailscale.com/blog/how-tailscale-works/
    stun_listen_addr: "0.0.0.0:3478"

    # Private key used to encrypt the traffic between headscale DERP
    # and Tailscale clients.
    # The private key file will be autogenerated if it's missing.
    #
    private_key_path: /var/lib/headscale/derp_server_private.key

    # This flag can be used, so the DERP map entry for the embedded DERP server is not written automatically,
    # it enables the creation of your very own DERP map entry using a locally available file with the parameter DERP.paths
    # If you enable the DERP server and set this to false, it is required to add the DERP server to the DERP map using DERP.paths
    automatically_add_embedded_derp_region: true

    # For better connection stability (especially when using an Exit-Node and DNS is not working),
    # it is possible to optionally add the public IPv4 and IPv6 address to the Derp-Map using:
    ipv4: 1.2.3.4
    ipv6: 2001:db8::1

  # List of externally available DERP maps encoded in JSON
  urls:
    - https://controlplane.tailscale.com/derpmap/default

  # Locally available DERP map files encoded in YAML
  #
  # This option is mostly interesting for people hosting
  # their own DERP servers:
  # https://tailscale.com/kb/1118/custom-derp-servers/
  #
  # paths:
  #   - /etc/headscale/derp-example.yaml
  paths: []

  # If enabled, a worker will be set up to periodically
  # refresh the given sources and update the derpmap
  # will be set up.
  auto_update_enabled: true

  # How often should we check for DERP updates?
  update_frequency: 24h

# Disables the automatic check for headscale updates on startup
disable_check_updates: false

# Time before an inactive ephemeral node is deleted?
ephemeral_node_inactivity_timeout: 30m

database:
  # Database type. Available options: sqlite, postgres
  # Please note that using Postgres is highly discouraged as it is only supported for legacy reasons.
  # All new development, testing and optimisations are done with SQLite in mind.
  type: sqlite

  # Enable debug mode. This setting requires the log.level to be set to "debug" or "trace".
  debug: false

  # GORM configuration settings.
  gorm:
    # Enable prepared statements.
    prepare_stmt: true

    # Enable parameterized queries.
    parameterized_queries: true

    # Skip logging "record not found" errors.
    skip_err_record_not_found: true

    # Threshold for slow queries in milliseconds.
    slow_threshold: 1000

  # SQLite config
  sqlite:
    path: /var/lib/headscale/db.sqlite

    # Enable WAL mode for SQLite. This is recommended for production environments.
    # https://www.sqlite.org/wal.html
    write_ahead_log: true

    # Maximum number of WAL file frames before the WAL file is automatically checkpointed.
    # https://www.sqlite.org/c3ref/wal_autocheckpoint.html
    # Set to 0 to disable automatic checkpointing.
    wal_autocheckpoint: 1000

  # # Postgres config
  # Please note that using Postgres is highly discouraged as it is only supported for legacy reasons.
  # See database.type for more information.
  # postgres:
  #   # If using a Unix socket to connect to Postgres, set the socket path in the 'host' field and leave 'port' blank.
  #   host: localhost
  #   port: 5432
  #   name: headscale
  #   user: foo
  #   pass: bar
  #   max_open_conns: 10
  #   max_idle_conns: 10
  #   conn_max_idle_time_secs: 3600

  #   # If other 'sslmode' is required instead of 'require(true)' and 'disabled(false)', set the 'sslmode' you need
  #   # in the 'ssl' field. Refers to https://www.postgresql.org/docs/current/libpq-ssl.html Table 34.1.
  #   ssl: false

### TLS configuration
#
## Let's encrypt / ACME
#
# headscale supports automatically requesting and setting up
# TLS for a domain with Let's Encrypt.
#
# URL to ACME directory
acme_url: https://acme-v02.api.letsencrypt.org/directory

# Email to register with ACME provider
acme_email: ""

# Domain name to request a TLS certificate for:
tls_letsencrypt_hostname: ""

# Path to store certificates and metadata needed by
# letsencrypt
# For production:
tls_letsencrypt_cache_dir: /var/lib/headscale/cache

# Type of ACME challenge to use, currently supported types:
# HTTP-01 or TLS-ALPN-01
# See: docs/ref/tls.md for more information
tls_letsencrypt_challenge_type: HTTP-01
# When HTTP-01 challenge is chosen, letsencrypt must set up a
# verification endpoint, and it will be listening on:
# :http = port 80
tls_letsencrypt_listen: ":http"

## Use already defined certificates:
tls_cert_path: ""
tls_key_path: ""

log:
  # Output formatting for logs: text or json
  format: text
  level: info

## Policy
# headscale supports Tailscale's ACL policies.
# Please have a look to their KB to better
# understand the concepts: https://tailscale.com/kb/1018/acls/
policy:
  # The mode can be "file" or "database" that defines
  # where the ACL policies are stored and read from.
  mode: file
  # If the mode is set to "file", the path to a
  # HuJSON file containing ACL policies.
  path: ""

## DNS
#
# headscale supports Tailscale's DNS configuration and MagicDNS.
# Please have a look to their KB to better understand the concepts:
#
# - https://tailscale.com/kb/1054/dns/
# - https://tailscale.com/kb/1081/magicdns/
# - https://tailscale.com/blog/2021-09-private-dns-with-magicdns/
#
# Please note that for the DNS configuration to have any effect,
# clients must have the `--accept-dns=true` option enabled. This is the
# default for the Tailscale client. This option is enabled by default
# in the Tailscale client.
#
# Setting _any_ of the configuration and `--accept-dns=true` on the
# clients will integrate with the DNS manager on the client or
# overwrite /etc/resolv.conf.
# https://tailscale.com/kb/1235/resolv-conf
#
# If you want stop Headscale from managing the DNS configuration
# all the fields under `dns` should be set to empty values.
dns:
  # Whether to use [MagicDNS](https://tailscale.com/kb/1081/magicdns/).
  magic_dns: true

  # Defines the base domain to create the hostnames for MagicDNS.
  # This domain _must_ be different from the server_url domain.
  # `base_domain` must be a FQDN, without the trailing dot.
  # The FQDN of the hosts will be
  # `hostname.base_domain` (e.g., _myhost.example.com_).
  base_domain: kliek

  # List of DNS servers to expose to clients.
  nameservers:
    global:
      # NextDNS (see https://tailscale.com/kb/1218/nextdns/).
      # "abc123" is example NextDNS ID, replace with yours.
      # - https://dns.nextdns.io/abc123

    # Split DNS (see https://tailscale.com/kb/1054/dns/),
    # a map of domains and which DNS server to use for each.
    split:
      {}
      # foo.bar.com:
      #   - 1.1.1.1
      # darp.headscale.net:
      #   - 1.1.1.1
      #   - 8.8.8.8

  # Set custom DNS search domains. With MagicDNS enabled,
  # your tailnet base_domain is always the first search domain.
  search_domains: []

  # Extra DNS records
  # so far only A and AAAA records are supported (on the tailscale side)
  # See: docs/ref/dns.md
  extra_records: []
  #   - name: "grafana.myvpn.example.com"
  #     type: "A"
  #     value: "100.64.0.3"
  #
  #   # you can also put it in one line
  #   - { name: "prometheus.myvpn.example.com", type: "A", value: "100.64.0.3" }
  #
  # Alternatively, extra DNS records can be loaded from a JSON file.
  # Headscale processes this file on each change.
  # extra_records_path: /var/lib/headscale/extra-records.json

# Unix socket used for the CLI to connect without authentication
# Note: for production you will want to set this to something like:
unix_socket: /var/run/headscale/headscale.sock
unix_socket_permission: "0770"
#
# headscale supports experimental OpenID connect support,
# it is still being tested and might have some bugs, please
# help us test it.
# OpenID Connect
oidc:
  only_start_if_oidc_is_available: true
  issuer: "https://idm.example.com/oauth2/openid/headscale"
  client_id: "headscale"
  client_secret: ""
  # Alternatively, set `client_secret_path` to read the secret from the file.
  # It resolves environment variables, making integration to systemd's
  # `LoadCredential` straightforward:
  # client_secret_path: "${CREDENTIALS_DIRECTORY}/oidc_client_secret"
  # client_secret and client_secret_path are mutually exclusive.

  # The amount of time from a node is authenticated with OpenID until it
  # expires and needs to reauthenticate.
  # Setting the value to "0" will mean no expiry.
  expiry: 180d

  # Use the expiry from the token received from OpenID when the user logged
  # in, this will typically lead to frequent need to reauthenticate and should
  # only been enabled if you know what you are doing.
  # Note: enabling this will cause `oidc.expiry` to be ignored.
  use_expiry_from_token: false
  # Customize the scopes used in the OIDC flow, defaults to "openid", "profile" and "email" and add custom query
  # parameters to the Authorize Endpoint request. Scopes default to "openid", "profile" and "email".

  scope: ["openid", "profile", "groups"]
  #  extra_params:
  #    domain_hint: example.com

#   # List allowed principal domains and/or users. If an authenticated user's domain is not in this list, the
#   # authentication request will be rejected.
#   allowed_domains:
#     - example.com
#   # Note: Groups from keycloak have a leading '/'
  allowed_groups:
    - headscale_users
    - [email protected]
    - headscale_admins
#   allowed_users:
#     - [email protected]
#
#   # Optional: PKCE (Proof Key for Code Exchange) configuration
#   # PKCE adds an additional layer of security to the OAuth 2.0 authorization code flow
#   # by preventing authorization code interception attacks
#   # See https://datatracker.ietf.org/doc/html/rfc7636
  pkce:
#     # Enable or disable PKCE support (default: false)
    enabled: false
#     # PKCE method to use:
#     # - plain: Use plain code verifier
#     # - S256: Use SHA256 hashed code verifier (default, recommended)
    method: S256
#
#   # Map legacy users from pre-0.24.0 versions of headscale to the new OIDC users
#   # by taking the username from the legacy user and matching it with the username
#   # provided by the OIDC. This is useful when migrating from legacy users to OIDC
#   # to force them using the unique identifier from the OIDC and to give them a
#   # proper display name and picture if available.
#   # Note that this will only work if the username from the legacy user is the same
#   # and there is a possibility for account takeover should a username have changed
#   # with the provider.
#   # Disabling this feature will cause all new logins to be created as new users.
#   # Note this option will be removed in the future and should be set to false
#   # on all new installations, or when all users have logged in with OIDC once.
#   map_legacy_users: true

# Logtail configuration
# Logtail is Tailscales logging and auditing infrastructure, it allows the control panel
# to instruct tailscale nodes to log their activity to a remote server.
logtail:
  # Enable logtail for this headscales clients.
  # As there is currently no support for overriding the log server in headscale, this is
  # disabled by default. Enabling this will make your clients send logs to Tailscale Inc.
  enabled: false

# Enabling this option makes devices prefer a random port for WireGuard traffic over the
# default static port 41641. This option is intended as a workaround for some buggy
# firewall devices. See https://tailscale.com/kb/1181/firewalls/ for more information.
randomize_client_port: false

[kradalby]

which OIDC provider do you use? I noticed that Google for example does not provide a username. If the provider does not provide one, it will not be set.

[ToxicMushroom]

I use https://github.com/kanidm/kanidm

[kradalby]

Can you provide a the claim json as an example?

[ToxicMushroom]

Can you provide a the claim json as an example?

It is in the original post under anything else ? in the oidc claims for my user with "profile", "email", "groups" scopes block

[ToxicMushroom]

I think I found the line here @kradalby

headscale/hscontrol/types/users.go

Line 178 in ede4f97

u.Name = claims.Username

The err that is checked does not seem to ever get printed.
I don't think my preferred_username passes the regex check in the FQDN function.

[kradalby]

I suppose there should be a logging of that message, but it needs to pass that regex.

[kradalby]

What is the username not passing the regex, out of curiosity?

[ToxicMushroom]

What is the username not passing the regex, out of curiosity?

[email protected]

I'm curious where the regex comes from tho, what purpose does it serve ?
But kanidm has the option to send the username without the domain part too so I'll configure it to do that.

[kradalby]

historically it comes from when our magicdns implementation used the username, so it validates that it is DNS safe. Since this has been removed, it can be removed, I am just a bit cautious opening it completely yet, so keeping it strict initially and being conservative atm feels the best.

Allowing @ would be sensible tho, so I'll update the PR to allow that.

[ToxicMushroom]

ooh then it makes sense yeah :)