Vespa Cloud Security Whitepaper

Table of Contents

Introduction

This document describes the Vespa Cloud service security features and operational procedures.

Concepts and architecture

Vespa Cloud overall architecture diagram

The Vespa Cloud consists of a Control Plane and a Date Plane. Each have their own web service APIs, respectively managing Vespa applications (Control), and interacting with a deployed Vespa application (Data).

The Control Plane manages deployment of applications in the zones they specify, and lets tenant administrators manage their tenant information in Vespa Cloud. The Control Plane is shared among all tenants in Vespa Cloud and is globally synchronized.

The Data Plane lets the tenants communicate with their deployed Vespa applications. It supports queries, feeding, and any other type of requests the tenant has configured and deployed in their application. The Data Plane is isolated for each tenant, application, and (optionally) service.

The Vespa Cloud is divided into Zones. A zone is a combination of an environment and a region and have names like prod.aws-us-east-1c. Zones are stand-alone and does not have critical dependencies on services outside the zone. Tenants can implement service redundancy by specifying that applications be deployed in multiple zones.

A Zone is managed by a Configuration Server cluster. These receive the application packages from the Control Plane on deployment and manages the local deployment process in the zone, including provisioning the node resources required to run the deployed application in the zone. Separately, it is responsible for maintaining those resources - replacing failed nodes, upgrading their OS and similar.

Vespa applications run on Nodes - a Linux container executed on a Host. The Host is the actual machine running the containers. Each Host has a management process that receives instructions from the Configuration Server about what containers should run on the Host. Once started, the containers ask the Configuration Server cluster what Vespa services of what application they should run.

It is the individual Node that contains the customer data such as indexes and document, and which receives the queries and feeding requests from the customer’s authenticated and authorized clients. Each Node is always dedicated to a single Vespa application cluster. Hosts are shared by default, but applications may specify that they require dedicated hosts to obtain an additional level of security isolation.

Service deployment

Control plane authentication and authorization

Control plane API access

All API operations towards the Vespa Cloud control plane require authorization, and no tenant or application information will be presented for unauthorized access. A user can present a valid OAuth2 token which will be verified by the API. If a OAuth2 token is not available the user can choose to use an API key instead. The intended use for API keys is for service automation (e.g. CI/CD workflows or Github actions), but they can also be used by developers.

Roles and privileges

Members of tenants in Vespa Cloud can be assigned to three different roles that grant different privileges:

  • Reader: Can read tenant and application metadata. This is the minimal privilege which is implicitly granted to all members of a tenant.
  • Developer: Can create applications, deploy to dev zones, and submit to prod zones. These are the privileges needed by members working on applications.
  • Administrator: Can manage members of a tenant and tenant metadata, such as tenant contact information and billing actions.

All role memberships are stored in an external identity provider.

Service isolation

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Nodes belonging to the same application are allowed to communicate with each other while nodes of different applications are isolated on the network layer and through authorization.

Communication between Vespa services is encrypted and authenticated using mutual TLS (mTLS). Identities and certificates are provided by infrastructure components that can validate the configuration.

Access control and service identity

Each host and node has a unique cryptographic service identity. This identify is required in all inter-service communication, including HTTPS and internal binary RPC protocols. On the host, node, and configuration server level there are authorization rules in place to ensure that only relevant services can communicate with each other and retrieve resources from shared services, like the configuration server.

Node isolation

The identity of the node is based on the tenant, application, and instance the node is part of. The host and configuration server will together establish the identity of the node. The configuration server tells the host which nodes it should start, and the host requests a cryptographic identity for the nodes from the identity provider.

This node identity is used for all internal communication inside the application.

Nodes are implemented as Linux containers on the hosts. Each node runs in their own container user namespaces, and each node has a dedicated IP address.

Host isolation

The lowest physical resource in the service architecture is a host. The configuration server is responsible for provisioning hosts and will keep track of known hosts, and reject any unknown hosts. Hosts only communicate directly with the configuration server and cannot communicate with each other.

Configuration isolation

Both nodes and hosts will consume application configuration from the configuration server. The configuration server will apply authorization rules based on the host and node identity. Authorization rules are based on least privilege. Hosts will only see which nodes to run, while the nodes are able to access the application configuration.

Network isolation

All communication between services is protected through mTLS. mTLS authorization is based on the identity mentioned above. In addition, network level isolation is used to prevent any unauthorized network access between services. The network rules are configured in the configuration server and applied by the host. Changes to the topology are reflected within minutes.

Communication

Data plane

All access to application endpoints are secured by mTLS. Upon deployment, every application is provided a certificate with SAN DNS names matching the endpoint names. This certificate will be automatically refreshed every 90 days. The application owner must provide a set of trusted Certificate Authorities which will be used by clients when accessing the endpoints.

Federation

It is possible for an application owner to federate calls to 3rd party services. Either as scheduled jobs, or per request. To support this use case we provide access to a credential storage in the customer’s AWS account.

Data Storage

Encryption at Rest

All customer data are encrypted at rest using a LUKS2 implementation with the following properties:

  • Cipher: aes-xts-plain64
  • Hash: SHA256
  • Key size: 256

The key is stored in a centralized key management service. Access to the key is controlled based on the host identity. The key is rotated on a yearly basis.

Data classification

All data handled by Vespa Cloud is classified into two different classes which has different policies associated with them.

  • Internal data: Information intended for internal consumption in Vespa Cloud operations. This includes system level logs from services that do not handle customer data. Internal data is readable by authenticated and authorized members of the Vespa Cloud engineering team.

  • Confidential data: Confidential data is data that is sensitive to Vespa Cloud or Vespa Cloud customers. Access to confidential data is subject to stringent business need-to-know. Access to confidential data is regulated and only granted to Vespa Cloud team members in a peer-approved, time-limited, and audited manner. All customer data is considered confidential.

Asset types

Asset Class Description
Control Plane data Internal The Control Plane maintains a database to facilitate orchestration of Vespa applications in multiple zones. This contains metadata about tenants and applications in Vespa Cloud.
Configuration Server data Confidential The configuration server database contains the Vespa application model as well as the orchestration database. Since the configuration server is part of establishing node and host identities, the configuration server data is considered confidential.
Infrastructure logs Internal Logs from infrastructure services like the configuration servers, the control plane services, etc. are considered internal. This includes logs from Control Plane, Configuration Servers, and Hosts.
Application package Internal The application.zip file uploaded to Vespa Cloud by the customer is considered internal. The application package contains settings and configuration that Vespa Cloud operations needs insight in to operate the platform.
Node logs Confidential The logs inside the Node may contain data printed by the customer. Because of this the logs are classified as confidential since Vespa Cloud cannot guarantee they are free of confidential data. This includes Data Plane access logs in addition to the node Vespa logs.
Core dumps / heap dumps Confidential Occasionally core dumps and heap dumps are generated for running services. These files may contain customer data and are considered confidential.
Node data Confidential All data on the node itself is considered confidential. This data includes the document data and the indexes of the application.

Logs

All logs are stored on the nodes where they are generated, but also archived to a remote object storage. All logs are kept for a maximum of 30 days. Access to logs is based on the classifications described above. All logs are persisted in the same geographic region as the Vespa application that generated them.

Archived logs are encrypted at rest with keys automatically rotated at regular intervals.

Logs on the node are encrypted at rest with the same mechanism that encrypts indexes and document databases.

Access management

Access to confidential data is only granted on a case-by-case basis. Access is reviewed, time-limited, and audited. No Vespa Cloud team member is allowed to access any confidential data without review.

Operational security

Vespa Cloud utilizes the security infrastructure and policies provided by the Yahoo Paranoids. This includes bug bounty programs, architecture security reviews, and policies for operations, monitoring, and auditing.

Development

Development of Vespa Cloud follows a CI/CD process where all code and configuration commits are reviewed by a team member. In addition we run static analysis to detect issues in source code and 3rd party dependencies. We participate in bug bounty programs where external security experts are paid to report security issues to us.

The team does periodic reviews with the Yahoo Paranoids team of the Vespa Cloud architecture. These reviews are both done as part of regular feature development process, and after-the-fact as part of full-picture reviews.

Patch management

Vespa is released up to 4 times a week, and we strive to upgrade any application to the latest version. OS upgrades to patch OS level issues are rolled out every 90 days. In case of a severe issue (security or functional) rollout of a fix (when available) will roll out as fast as possible.

Incident management

Any unexpected production issue (security or functional) is handled through our incident management process. All non-security incidents will be announced through our console. Security incidents will be communicated directly to each affected customer. When the incident is handled, a post mortem review process is initiated. If required (e.g in a potential security breach), a forensic process will also be initiated to find any potential leaks.