iss/sub claims), which Workload selector decides where to apply the authorization policy. workload instance info such as labels attached to the pod/VM, or any other info Zero trust network architecture inverts the assumptions of perimeter security. When access control is enabled, the default behavior is deny (deny-by-default) Fine-grained policy. Bounding in time limits the risk of compromised credentials. Bug description Hi all, As the documentation says, we should have mtls enabled in our cluster or the microservices that want to user AuthiorizationPolicy using the principal field. Bounding in time with dynamic policy enforcement on short-lived sessions ensures authorization is based on up-to-date policy. Bug description Have a question about this project? Operations are listed in the to field, and answer the what? When the spec/selector field is omitted, the rules are namespace-wide. - workload selector can be used to further restrict where a policy applies. - Suffix match: abc will match on value abc and xabc. Hi all, to your account. The following authorization policy applies to all workloads in namespace foo. Secure, authentic communication. (Assuming the root namespace is The following authorization policy applies to workloads containing label [Documentation] Istio Authorization Policy "principals" works without So should you use Istio AuthorizationPolicies over plain Kubernetes NetworkPolicies? Optional. Those resources were part of the v1alpha1 API, that is now completely replaced by the v1beta1 API. For gRPC service, this should be the fully-qualified name in the form of Azure AKS. Access requests inside an enterprise-owned or other private network must meet the same security requirements as communication from any other location. foo. the configuration namespace in which the resource is present. Limited blast radius of perimeter breaches prevents lateral movement by attackers. Just like any other mesh configuration, authorization rules can be specified through Kubernetes CRDs. Lets take a look at the operation field as well: along methods, valid matchers are hosts, ports, paths and their exclusion pairs, like notHosts. When a NetworkPolicy selects a specific pod, that pod will reject any connections, except those that are explicitly allowed. In an increasingly complex networking environment, maintaining a robust perimeter is increasingly difficult. Optional. Bounding in time with dynamic policy enforcement on short-lived sessions ensures authorization is based on up-to-date policy. Real-time and auditable assurance of security posture and regulatory compliance. As much information as possible should be collected and used to improve security posture. Optional. Single IP (e.g. If you want to have a finer grained authorization model, you should go with Istio, but if your only requirement is that pod A should only be able to communicate with pod B, then NetworkPolicies are just as good. The data plane consists of sidecar proxies running alongside the application containers in the same pod, and they are responsible for forwarding all incoming, and outgoing traffic to the application. Mutual TLS must be enabled before using any of the following fields in the authorization policy: Reference: https://istio.io/v1.7/docs/concepts/security/#dependency-on-mutual-tls, The point is, we apply this configuration bellow and the AuthorizationPolicy is working without mTls enabled. Rules are built of three parts: sources, operations and conditions. version: v1 in all namespaces in the mesh. Istio authorization doesnt need to be explicitly enabled. when the request has a valid JWT token issued by https://accounts.google.com. 1.2.3.4) and CIDR (e.g. This allows the integrity and security posture of all assets to be continuously monitored and policy enforcement continuously assured. The new API was introduced in Istio 1.4, and from Istio 1.6, the old API is not supported anymore. Fine-grained observability allows real-time assurance and post-facto auditability of policy enforcement plus the necessary data for troubleshooting and analysis. If not set, the authorization policy will be applied to all workloads in the For organizations operating in a federal regulatory environment, Tetrate Istio Distro is the only distribution of Istio with FIPS-verified builds available. A list of methods, which matches to the request.method attribute. label selector app: httpbin, version: v1. The API is quite simple, it consists of a single CRD, called AuthorizationPolicy, but more on the YAML details later. Istio has a data plane, and a control plane. Register for an evaluation version](https://eti.cisco.com/appnet/smm/download) and run the following command to install the CLI tool (KUBECONFIG must be set for your cluster): Register for the free tier version of Cisco Service Mesh Manager (formerly called Banzai Cloud Backyards) and follow the Getting Started Guide for up-to-date instructions on the installation. The AuthorizationPolicy should not work? When CUSTOM, DENY and ALLOW actions are used for a workload at the same time, the CUSTOM action is evaluated first, then the DENY action, and finally the ALLOW action. Authenticated and authorized workloads are protected from perimeter breaches. A list of source peer identities (i.e. A few examples are policies based on HTTP methods, URIs, or HTTP headers. For an in-depth guide to NISTs security recommendations and how Tetrate can help you implement the standard, check out Tetrates Guide to Federal Security Requirements for Microservices. Optional. This implies implementing at least TLS for all communication, with mTLS and associated secure workload identities as a best practice for service-to-service communication. Then Envoy returns the result, either ALLOW or DENY. And, the mesh is a tightly controlled element of the system that can be hardened with more eyes and closer inspection (NIST SP 800-204B, 5.1). Zero trust security is emerging as a preferred approach for enterprises to secure both their traditional and modern, cloud-native applications. The sidecars are Envoy proxies, and the control plane is now basically a single service, called istiod. A request is evaluated against the authorization policies when it arrives to the proxy. Already on GitHub? This means that Weve blogged a lot about connect, even more about observe, and also had a few articles about secure. Optional. The Kubernetes docs define network policies as follows: A network policy is a specification of how groups of pods are allowed to communicate with each other and other network endpoints. Must be used only with HTTP or gRPC. Istio uses mutual TLS to securely pass some information . This post tries to fill that gap, and discusses Istio's access control model, or more specifically AuthorizationPolicies. Access to resources should be observable. Currently AuthorizationPolicy only supports ALLOW action. Operation specifies the operations of a request. Another difference worth mentioning is that NetworkPolicies work in an additive, whitelist model. This kind of access control is enforced at the application layer by the Envoy sidecar proxies. Authorization policy supports CUSTOM, DENY and ALLOW actions for access control. If you feel this issue or pull request deserves attention, please reopen the issue. Because Envoy understands different protocols (most commonly HTTP), it allows for a rich set of attributes to base policy decisions on. Sign up for a free GitHub account to open an issue and contact its maintainers and the community. Authentication and authorization are bound to a short-lived session after which they must be re-established. to a proxy. Authorization Policy scope (target) is determined by metadata/namespace and A list of paths, which matches to the request.url_path attribute. The following is a workload-wide policy, that applies to pods in the backyards-demo namespace that have the app=catalog label. same namespace as the authorization policy. The name of an Istio attribute. It must be explicitly authenticated and authorized as well. If not set, any host is allowed. In the example, the source is a principal, but it can be requestPrincipals, namespaces or ipBlocks as well. Operation specifies the operation of a request. Istio satisfies the three requirements of a reference monitor (NIST SP 800-204B, 5.1). Using istio operator 1.7.2 The scope of label search is restricted to The following authorization policy applies to workloads containing label Architecture Istio Authorization can be . A list of ports, which matches to the destination.port attribute. The matching criteria includes the metadata associated with a proxy, Any string field in the rule supports Exact, Prefix, Suffix and Presence match: Do you have any suggestions for improvement? namespace, the policy applies to all namespaces in a mesh. First, lets see how are these rules enforced in Istio. Istio Archive Similarly to telemetry and traffic management, the real deal happens in the data plane. https://istio.io/v1.7/docs/concepts/security/#dependency-on-mutual-tls, https://preliminary.istio.io/latest/docs/ops/configuration/traffic-management/tls-configuration/#auto-mtls. A NetworkPolicy cannot do these, because these concepts are unknown at the network and transport layers. Network location and reachability do not imply trust. specified, all conditions need to match in order for the workload instance to be It also contains an operation, that only matches GET requests. that the proxy provides to Istio during the initial handshake. A list of namespaces, which matches to the source.namespace All checks are performed runtime by the Envoy proxys authorization engine. - metadata/namespace tells which namespace the policy applies. Bounding in time limits the risk of compromised credentials. Optional. Sources are specified in the from field, and answer the who? If any ALLOW policies are applied to a workload, traffic is denied to that workload by default, and only those requests that are explicitly configured are allowed. Istio policy enforcement works at the application layer (L7), - thats where the Envoy proxies operate - while Kubernetes network policies work at the network (L3) and transport layers (L4). The new model simplifies configuration (one CRD instead of three), supports ingress and egress gateways, and better aligns with the Istio configuration model, as it is applied to workloads instead of services. To enforce access control, you have to apply at least one AuthorizationPolicy resource. Introduction to Istio access control Banzai Cloud AuthorizationPolicies can be mesh-, namespace-, and workload-wide depending on the namespace and the spec/selector field. Operating at the application layer has its advantages. So to recap, the above policy allows GET requests from workloads with the cluster.local/ns/backyards-demo/sa/frontpage identity to backyard-demo/catalog, and denies everything else. Optional. Optional. - namespace test from specifies the source of a request. When no AuthorizationPolicies select a workload, all requests are allowed. Optional. when specifies a list of additional conditions of a request. if multiple authorization policies apply to the same workload, the effect is additive. Istio can be used to enforce access control between workloads in the service mesh using the AuthorizationPolicy custom resource. The perimeter of trust around resources should be as small as possibleideally zero. the workload. For someone whos just getting to know Istio, it can be confusing that they may bump into blog posts about Istio access control containing mentions of CRDs like ClusterRbacConfig, ServiceRole, ServiceRoleBinding. Optional. In most cases the when field can be omitted, its usually only used in complex scenarios, but it can be used to further customize request matching with a list of supported Istio attributes. Kubernetes network policies are implemented by different networking solutions, like Calico. It gives the user a very powerful and flexible, yet performant way of authorization between Kubernetes workloads. When multiple policies are applied to the same workload, Istio applies them additively. A rubric for a zero trust system is that you could expose it to the open internet and it would still be secure, with no unauthorized access to systems, data, or communication. External Authorization. But operating at the network layer has the advantage of being universal, since all network applications use IP. If set to root To establish zero trust security guidelines for industry and the U.S. federal government, the National Institute of Standards and Technology (NIST) establishes zero trust security guidelines in a series of publications starting with SP 800-207 on zero trust architecture in general and its companion SP 800-204 series on security standards for microservices. RED Alerts: a practical guide for alerting in production systems, What's new in Istio 1.8, a quick walkthrough, "cluster.local/ns/backyards-demo/sa/frontpage", "cluster.local/ns/backyards-demo/sa/catalog", "cluster.local/ns/backyards-demo/sa/bookings", Backyards (now Cisco Service Mesh Manager), free tier version of Cisco Service Mesh Manager, these rules are enforced for the pods that match the label selector, it denies every other request to the movies workload, the same goal could have been achieved with two different, mutual TLS is required to securely pass information between Envoy proxies, and its needed for some of the fields, like, plain TCP traffic can also be authorized by Istio, but in that case the, most fields support exact, prefix, suffix and presence value matching: prefix and suffix is when the value starts or ends with a. When talking about AuthorizationPolicies, we have to mention Kubernetes NetworkPolicies, because they are quite similar in terms of what problem they are trying to solve. This ensures that access decisions are made frequently and with the most recent context available. Fine-grained policy. For more details about network policies check out our blog post, Exploring Network Policies in Kubernetes. the authorization policies selecting the workload. Also, insights gained from observing should be fed back to improve policy. In a zero trust network, every resource is protected internally as if it were exposed to the open internet. A list of hosts, which matches to the request.host attribute. Unlike NetworkPolicies, AuthorizationPolicies support both ALLOW and DENY actions. Optional. The control plane on the other hand is accepting user configuration through CRDs, and - among a few other things - transforms these CRDs to Envoy configuration and delivers it to the proxies. Istio Authorization can be used to enforce access control rules between workloads. All communication should be secure, regardless of network location. Theres no easy answer to which one is better?, because they are good at different things. Secure, authentic communication. http://github.com/istio/istio/operator, Environment where the bug was observed (cloud vendor, OS, etc) to access the workload with: Well, it always depends on your use case. Istio / Authorization These policies are additive, they do not conflict, and order of evaluation is irrelevant. attribute. It allows requests from: Here are NISTs core zero trust architecture principles and the Kubernetes and Istio reference architecture recommended to apply them in practice. A list of rules to specify the allowed access to the workload. If multiple conditions are Istio Authorization Policy enables access control on workloads in the mesh. Steps to reproduce the bug Backyards (now Cisco Service Mesh Manager) provides an Istio control panel where you can track, visualize or even manage your Istio YAML configuration. (Assuming the root namespace is configured to "istio-config"). One or more labels that indicate a specific set of pods/VMs Must be used only with HTTP. A list of IP blocks, which matches to the source.ip attribute. Cvss scores, vulnerability details and links to full CVE details and references Tetrate Enterprise ready service mesh, SP 800-207 on zero trust architecture in general, SP 800-204 series on security standards for microservices, mTLS and associated secure workload identities as a best practice for service-to-service communication, read Zack Butchers Zero Trust Architecture white paper, Tetrates Guide to Federal Security Requirements for Microservices, Lack of a built-in certificate management mechanism needed to enforce TLS between pods, Lack of an identity and access management mechanism, Firewall policy that operates at OSI L3, but not L7 and, therefore, unable to peek into data packets or to make metadata-driven decisions. Istio claims that it helps to connect, secure, control and observe services. It doesnt contain a condition, which means match any conditions. If not set, access is denied unless explicitly allowed by other authorization policy. Apply any authorization policy using principals rule without mtls enabled, How was Istio installed? If you need a unified and consistent way to secure and manage services across a fleet of applications, check out Tetrate Service Bridge (TSB), our comprehensive edge-to-workload application connectivity platform built on Istio and Envoy. Istio Authorization Policy enables access control on workloads in the mesh. A list of request identities (i.e. Source specifies the source of a request. This AuthorizationPolicy is applied to the catalog workload in the backyards-demo namespace, and while not explicitly specified, its an ALLOW rule, so it will deny all traffic that doesnt match the rules described here. 1.2.3.0/24) are supported. As a companion to NISTs standards for zero trust architecture in general, NIST has also published standards for how to apply zero trust principles specifically to microservices applications. AuthorizationPolicy enables access control on workloads. Currently, only label based selection mechanism is supported. This post tries to fill that gap, and discusses Istios access control model, or more specifically AuthorizationPolicies. Encryption on the wire prevents eavesdropping and also ensures messages are authentic and unaltered. apiVersion: security.istio.io/v1beta1 kind: AuthorizationPolicy metadata: name: policy namespace: istio - config spec: selector: matchLabels: version: v1. If youre looking for a migration path, Id recommend to read the official blog post. Then at last, conditions are described in the when field and answer the when? question. This should apply to all inbound, outbound, and service-to-service access. The main networking security gaps in Kubernetes are (NIST SP 800-204B, 2.1.1): To augment Kubernetes for security, Istio acts as a security kernel in the NIST reference architecture. For example, the following authorization policy applies to workloads matched with Istio also support exclusion matching, by providing the same fields with a not prefix. Shows how to integrate and delegate access control to an external authorization system. When access is granted, it should be granted with the least privilege required. If youre reading this article, you should already be familiar with Istios high level architecture, but heres a (very) brief recap. If not set, any request principal is allowed. - Prefix match: abc will match on value abc and abcd. For example, the following authorization policy denies all requests to workloads Condition specifies additional required attributes. Optional. Rule allows access from a list of sources to perform a list of operations when As the documentation says, we should have mtls enabled in our cluster or the microservices that want to user AuthiorizationPolicy using the principal field. Thank you for your contributions. Optional. Frequent policy evaluation. The namespace of the resource determines the namespace where the rules will be enforced. If youre looking for the fastest way to get to production with Istio, check out our open source Tetrate Istio Distro (TID) is a vetted, upstream distribution of Istioa hardened image of Istio with continued support that is simpler to install, manage, and upgrade. Or you can even use the two concepts side-by-side. app: httpbin in namespace bar. in namespace foo. See the full list of supported attributes. Please see this wiki page for more information. To start experimenting with Istio and AuthorizationPolicies, we suggest to try Backyards (now Cisco Service Mesh Manager) and get up and running with an example application in minutes. Traditional network security relies on a strong defensive perimeter around a trusted internal network to keep bad actors out and sensitive data in. Expected behavior Source specifies the source identities of a request. Bounding in space allows for high granularity of policy enforcement. Access to resources should be bounded in time. The selector, that is a standard Kubernetes label selector, can be used to restrict the policy to specific workload(s) in the namespace, making the policy workload-wide. For example the below example matches request header values: Finally, take a look at a more complex rule to see how it matches requests when most fields contain multiple entries: This final example contains two separate rules in one policy with an ALLOW action. It basically answers the question: who can access what, under which specific conditions? Istio uses mutual TLS to securely pass some information from the client to the server. - GET method at paths of prefix /info or, So you can apply policies regardless of the layer 7 protocol, and these will be enforced in the kernel space.