Bind installed releases to signed artifact receipts

docs/installer-receipt-authority-keyring.schema.json

@@ -0,0 +1,53 @@
+{
+  "$schema": "https://json-schema.org/draft/2020-12/schema",
+  "$id": "https://git.add-ideas.de/add-ideas/govoplan/src/branch/main/docs/installer-receipt-authority-keyring.schema.json",
+  "title": "GovOPlaN installer receipt authority keyring",
+  "type": "object",
+  "additionalProperties": false,
+  "required": ["schema_version", "purpose", "keys"],
+  "properties": {
+    "$schema": { "type": "string", "format": "uri-reference" },
+    "schema_version": { "const": "0.1.0" },
+    "purpose": { "const": "govoplan.installer-receipt-authorities" },
+    "keys": {
+      "type": "array",
+      "minItems": 1,
+      "maxItems": 64,
+      "items": { "$ref": "#/$defs/key" }
+    }
+  },
+  "$defs": {
+    "opaque_id": {
+      "type": "string",
+      "minLength": 1,
+      "maxLength": 160,
+      "pattern": "^[A-Za-z0-9][A-Za-z0-9._:-]*$"
+    },
+    "key": {
+      "type": "object",
+      "additionalProperties": false,
+      "required": ["key_id", "status", "public_key", "allowed_scopes"],
+      "properties": {
+        "key_id": { "$ref": "#/$defs/opaque_id" },
+        "status": {
+          "enum": ["active", "next", "revoked", "disabled", "retired"]
+        },
+        "public_key": {
+          "type": "string",
+          "minLength": 1,
+          "maxLength": 256,
+          "contentEncoding": "base64"
+        },
+        "allowed_scopes": {
+          "type": "array",
+          "minItems": 1,
+          "maxItems": 1,
+          "uniqueItems": true,
+          "items": { "const": "installed_release_origin" }
+        },
+        "not_before": { "type": "string", "format": "date-time" },
+        "not_after": { "type": "string", "format": "date-time" }
+      }
+    }
+  }
+}