This commit adds two extensions to template variables
in roles and adds support for regular expressions
and group captures in role mapping of trusted clusters.
1. Roles node_labels can expand variables from traits:
allow:
node_labels:
'{{external.key}}': '{{external.val}}'
deny:
node_labels:
'{{external.key}}': '{{external.val}}'
If traits variable is not found, label key pair in allow or
deny rule will be set to empty key or value, so if 'external.val'
trait is missing, the resulting role will not match
allow or deny rule:
allow:
node_labels:
'': 'val'
deny:
node_labels:
'': 'val'
Same thing will happen for missing value:
allow:
node_labels:
'key': ''
deny:
node_labels:
'key': ''
2. Trusted cluster role mapping can now
support advanced expressions:
a. Glob values will math any string, including
empty one
role_map:
- remote: 'cluster-*'
local: [clusteradmin]
a. Regular expression syntax is supported:
Syntax: https://github.com/google/re2/wiki/Syntax
Brackets can be used as a capture group and referred
to with expand variable:
role_map:
- remote: '^clusteradmin-(.*)$'
local: [unprivileged-$1]
Will map incoming role 'clusteradmin-account-1' to 'guest-account-1'.
3. Same regular expression syntax is supported for SAML and OIDC
mappings:
a. Glob matches of values instead of static matches:
claims_to_roles:
- {claim: "roles", value: "gravitational/*", roles: ["clusteradmin"]}
b. Regexp matches with subgroup expands:
attributes_to_roles:
- {name: "roles", value: "^gravitational/(.*)$", roles: ["cluster-$1"]}
Russell Jones