Attribute-Role-Based Hybrid Access Control Library
V2.0 Breaking Changes
Theconditionsproperty has been removed from theactionobject due to its side effects. Instead, you can use thescopeproperty to add custom attributes and validate them using application logic.
npm install simple-access --save- Hybrid access control with the best features from RBAC & ABAC
- Ability to filter resource data based on granted permission
- Simplicity & flexibility
Access control is a security technique that regulates who or what can view or use resources in a computing environment.
Access Control involves:
- Preventing unauthorized users from gaining access to resources
- Preventing legitimate users from accessing resources in an unauthorized manner
- Enabling legitimate users to access resources in an authorized manner
Role-Based Access Control is a policy-neutral access-control mechanism defined around roles and privileges assigned to a user.
RBAC is an additive model, so if you have overlapping role assignments, your effective grants are the union of your role assignments.
Example:
If we have an API the provides data to eCommerce application, we may have a role of manager with access to a resource product and allowed actions ["create", "read", "update"], and another role operation with access to a resource product and allowed actions ["archive"]. So Any users with both manager and operation roles will be able to ["create", "read", "update", "archive"] products.
Attribute-Based Access Control provides access to users based on who they are rather than what they do.
An entity capable of accessing resources.
An entity that contains and/or receives information to which access is controlled, like "Files", "Messages".
Role is the level of access given to subject (user or business entity) when this role assigned to it, it is properly viewed as a semantic construct around which access control policy is formulated.
- Role may grant access to one or more unique resources
- Resource may grant access to resource with based on one or more unique actions
- Action may have list of attributes that can be used to filter resource data
Subject (User or business entity) can have one or more roles assigned based on their responsibilities and qualifications.
Role Schema
{
"name": "string",
"resources": [
{
"name": "string",
"actions": [
{
"name": "string",
"attributes": ["string"],
"scope": "object"
}
]
}
]
}Scope is just an object that may include any metadata to be used but applications to evaluate additional constraints on subject based on application business logic.
Permission describes the way in which a subject may access a resource
Permission Schema
{
"granted": "boolean",
"access": {
"roles": ["string"],
"action": "string",
"resource": "string"
},
"grants": "object",
"attributes": ["string"],
"scope": "object"
}This library does not handle roles storage and management (Not the library concern), It has a basic MemoryAdapter implemented by extending BaseAdapter , If you need to handle more complex scenarios you will probably need to extend BaseAdapter implementing your own storage for example using [MySQL, MongoDB, Redis]
Memory adapter is a built-in roles adapter that stores all roles data into memory with simple structure.
You can implement your own roles adapter by extending BaseAdapter class and implement getRolesByName method, considering that the getRolesByName can return Array<Role> or Promise<Array<Role>> and you can define the return type when creating your adapter class.
Example:
import { BaseAdapter, Role, ErrorEx } from "simple-access";
export class MemoryAdapter<
R extends [string, string, string]
> extends BaseAdapter<R, Array<Role<R>>> {
private _roles: Array<Role<R>>;
private _cache: { [k: string]: Role<R> } = {};
constructor(roles: Array<Role<R>>) {
super("MemoryAdapter");
this.setRoles(roles);
}
setRoles(roles: Array<Role<R>>): void {
if (roles == null || !Array.isArray(roles) || roles.length === 0) {
throw new ErrorEx(
ErrorEx.VALIDATION_ERROR,
`Missing/Invalid roles array in "${this.constructor.name}"`
);
}
this._roles = roles;
this._cache = {};
// Cache roles by name
this._roles.forEach((role: Role<R>) => {
// this.validateGrant(grant, true);
this._cache[role.name] = role;
});
}
getRoles(): Array<Role<R>> {
return this._roles;
}
getRolesByName(names: Array<Role<R>["name"]>): Array<Role<R>> {
const result: Array<Role<R>> = [];
if (names == null) {
throw new ErrorEx(
ErrorEx.VALIDATION_ERROR,
`Roles names array can not be null or undefined`
);
}
for (let i = 0; i < names.length; i += 1) {
if (this._cache[names[i]] != null) {
result.push(this._cache[names[i]]);
}
}
return result;
}
}
- Subject (user or business entity) assigned one or more roles
- Subject request access to a resource
- Simple Access check subject set of roles to validate access to provided resource and action
- Simple Access returns permission object
Let's use the following set of roles as an example:
import type { Role } from "simple-access";
type RoleNamesType = "administrator" | "operation";
type ResourceNamesType = "product" | "order" | "file";
type ActionNamesType = "create" | "read" | "update" | "delete"
type RoleDefinition = [RoleNamesType, ResourceNamesType, ActionNamesType]
const roles: Role<RoleDefinition>[] = [
{
"name": "administrator",
"resources": [
{"name": "product", "actions": ["*"]},
{"name": "order", "actions": ["*"]},
{"name": "file", "actions": ["*"]}
]
},
{
"name": "operation",
"resources": [
{
"name": "product",
"actions": [
{"name": "create", "attributes": ["*"]},
{"name": "read", "attributes": ["*"]},
{"name": "update", "attributes": ["*","!history"]},
{
"name": "delete",
"attributes": ["*"]
}
]
},
{
"name": "order",
"actions": [
{"name": "create", "attributes": ["*"]},
{"name": "read", "attributes": ["*"]},
{"name": "update", "attributes": ["*"]}
]
}
]
}
];You can check access using can method:
can(role: Array<string> | string, action: string, resource: string): Promise<Permission> | Permission
Check subject (with "operation" role) permission to "read" the resource "order", please note that can method return type depends on the return type of getRolesByName method in the adaptor you are using. In the following example the getRolesByName method in the MemoryAdaptor return type is Array<Role>
import {
type Role,
SimpleAccess,
MemoryAdapter
} from "simple-access";
import type {
RoleDefinition
} from './roles';
type RoleNamesType =
"administrator"
| "operation";
type ResourceNamesType =
"product"
| "order"
| "file";
type ActionNamesType =
"create"
| "read"
| "update"
| "delete"
type RoleDefinition = [RoleNamesType, ResourceNamesType, ActionNamesType]
const roles: Role<RoleDefinition>[] = [
{
"name": "administrator",
"resources": [
{
"name": "product",
"actions": ["*"]
},
{
"name": "order",
"actions": ["*"]
},
{
"name": "file",
"actions": ["*"]
}
]
},
{
"name": "operation",
"resources": [
{
"name": "product",
"actions": [
{
"name": "create",
"attributes": ["*"]
},
{
"name": "read",
"attributes": ["*"]
},
{
"name": "update",
"attributes": ["*", "!history"]
},
{
"name": "delete",
"attributes": ["*"]
}
]
},
{
"name": "order",
"actions": [
{
"name": "create",
"attributes": ["*"]
},
{
"name": "read",
"attributes": ["*"]
},
{
"name": "update",
"attributes": ["*"]
}
]
}
]
}
];
const adapter = new MemoryAdapter(roles);
const simpleAccess = new SimpleAccess<RoleDefinition, typeof adapter>(adapter);
const permission = simpleAccess.can("operation", "read", "order");
if (permission.granted) {
console.log("Permissin Granted");
}The returned permission
{
"granted": true,
"access": {
"roles": [
"operation"
],
"action": "read",
"resource": "order"
},
"grants": {
"product": {
"create": {
"name": "create",
"attributes": [
"*"
]
}
}
},
"attributes": [
"*"
],
"scope": {}
}
canfunction only checks if subject with assigned role operation can access the resource order through read action, It will not filter resource data, as this functionality provided through other functions and needs additional information to work properly.
Simple Access will merge overlapped roles before validation according to these details:
- Resources are merged (Union).
If subject assigned the previous set of roles
["administrator", "operation"]then this subject will have access to these resource["product", "order", "file"] - Actions are merged (Union), and the most permissive action will override.
- Role A with resource order and actions * will override role B with actions
["read", "create"] - Role A with resource order and actions
["read", "update"]and role B with actions["create", "delete"]will be merged in one resource order with actions["read", "update", "create", "delete"]
- Role A with resource order and actions * will override role B with actions
- Attributes are merged, and the most permissive attributes will override.
- Attributes
["*"]will override attributes["name", "age", "!address"] - Attributes
["name", "age"]will merge with attributes["address"]into new attributes array["name", "age", "address"] - Attributes
["*", "!address"]will be merged with attributes["age"]into new attributes array["*", "!address"] - Attributes
["*", "!age"]will be merged with attributes["*", "!image", "!address"]into new attributes array["*"]and["age" , "image", "address"]will be allowed because they are not negated from both sides - Attributes
["*", "!age"]will be merged with attributes["image"]into new attributes array["*", "!age"]and"image"attributes will be omitted because its by default allowed
- Attributes
Projected (Allowed) attributes gets merged based on a union operation
Negated (Not allowed) attributes gets merged based on intersection operation
- Scopes are merged (Union), and the most permissive scope will override.
- Empty scope
{}will override all other scopes - Scope
{"group": 123}will be merged with scope{"tenant": 321}into:
{ "group": 123, "tenant": 321 } - Empty scope
Example:
import {
type Role,
SimpleAccess,
MemoryAdapter
} from "simple-access";
import type {
RoleDefinition
} from './roles';
type RoleNamesType =
"administrator"
| "operation";
type ResourceNamesType =
"product"
| "order"
| "file";
type ActionNamesType =
"create"
| "read"
| "update"
| "delete"
type RoleDefinition = [RoleNamesType, ResourceNamesType, ActionNamesType]
const roles: Role<RoleDefinition>[] = [
{
"name": "administrator",
"resources": [
{
"name": "product",
"actions": ["*"]
},
{
"name": "order",
"actions": ["*"]
},
{
"name": "file",
"actions": ["*"]
}
]
},
{
"name": "operation",
"resources": [
{
"name": "product",
"actions": [
{
"name": "create",
"attributes": ["*"]
},
{
"name": "read",
"attributes": ["*"]
},
{
"name": "update",
"attributes": ["*", "!history"]
},
{
"name": "delete",
"attributes": ["*"]
}
]
},
{
"name": "order",
"actions": [
{
"name": "create",
"attributes": ["*"]
},
{
"name": "read",
"attributes": ["*"]
},
{
"name": "update",
"attributes": ["*"]
}
]
}
]
}
];
const adapter = new MemoryAdapter(roles);
const simpleAccess = new SimpleAccess<RoleDefinition, typeof adapter>(adapter);
const permission = simpleAccess.can(["operation", "support"], "read", "order");
if(permission.granted) {
console.log("Permissin Granted");
}Simple Access can filter resource object data based on specific permission and return only allowed attributes.
Simple Access is depending on Floppy Filter library for complex object filtering, Please check its documentation to know how to select or negate attributes in an efficient way.
You can do this using filter function:
filter(permission: Permission, data: Object): Object
Example:
import {
type Role,
SimpleAccess,
MemoryAdapter
} from "simple-access";
import type {
RoleDefinition
} from './roles';
type RoleNamesType =
"administrator"
| "operation";
type ResourceNamesType =
"product"
| "order"
| "file";
type ActionNamesType =
"create"
| "read"
| "update"
| "delete"
type RoleDefinition = [RoleNamesType, ResourceNamesType, ActionNamesType]
const roles: Role<RoleDefinition>[] = [
{
"name": "administrator",
"resources": [
{
"name": "product",
"actions": ["*"]
},
{
"name": "order",
"actions": ["*"]
},
{
"name": "file",
"actions": ["*"]
}
]
},
{
"name": "operation",
"resources": [
{
"name": "product",
"actions": [
{
"name": "create",
"attributes": ["*"]
},
{
"name": "read",
"attributes": ["*"]
},
{
"name": "update",
"attributes": ["*", "!history"]
},
{
"name": "delete",
"attributes": ["*"]
}
]
},
{
"name": "order",
"actions": [
{
"name": "create",
"attributes": ["*"]
},
{
"name": "read",
"attributes": ["*"]
},
{
"name": "update",
"attributes": ["*"]
}
]
}
]
}
];
const adapter = new MemoryAdapter(roles);
const simpleAccess = new SimpleAccess<RoleDefinition, typeof adapter>(adapter);
const resource = {
"authorId": 1002,
"price": 75.08
};
const permission = simpleAccess.can("operation", "read", "order");
if(permission.granted) {
const filteredResource = simpleAccess.filter(permission, resource);
}For simplicity and flexibility you can also call filter from Permission object
const permission = simpleAccess.can("operation", "read", "order");
if(permission.granted) {
const filteredResource = permission.filter(resource);
}MIT