sec-design-deep-analysis.md

Deep Security Analysis of Ceph Distributed Storage System

1. Objective, Scope, and Methodology

1.1. Objective:

The primary objective of this deep security analysis is to thoroughly examine the security architecture of the Ceph distributed storage system, as outlined in the provided "Project Design Document: Ceph Distributed Storage System for Threat Modeling (Improved)". This analysis aims to identify potential security vulnerabilities and weaknesses within key Ceph components, understand their security implications, and propose specific, actionable, and Ceph-tailored mitigation strategies. The focus is on providing the development team with a clear understanding of security risks and concrete steps to enhance the security posture of their Ceph deployment.

1.2. Scope:

This analysis encompasses the following key components of the Ceph architecture, as detailed in the design document:

• Ceph Monitors (MONs): Focusing on authentication, authorization, consensus mechanisms, and data sensitivity.
• Ceph Managers (MGRs): Analyzing management interface security, module security, and access control.
• Ceph Object Storage Devices (OSDs): Examining data at rest encryption, data integrity, access control enforcement, and resource exhaustion risks.
• Ceph Metadata Servers (MDSs): Investigating metadata security, access control for CephFS, and availability concerns.
• RADOS Gateways (RGWs): Analyzing API security, authentication, authorization, data in transit encryption, and web application vulnerabilities.
• Client Libraries (LibRados, RBD, CephFS Clients): Focusing on client-side vulnerabilities, secure credential handling, and input validation.

The analysis will primarily utilize the provided "Project Design Document" and infer architectural details and data flow based on the component descriptions and the high-level architecture diagram. While referencing the Ceph codebase (https://github.com/ceph/ceph) for deeper technical understanding is beneficial, this analysis will be based on the information provided in the design review document for the sake of this exercise.

1.3. Methodology:

The methodology for this deep analysis will involve the following steps:

1. Document Review: Thoroughly review the provided "Project Design Document" to understand the Ceph architecture, key components, and initial security considerations.
2. Component-Level Security Analysis: For each key component within the scope, analyze the "Key Security Aspects" identified in the document.
   • Elaborate on Security Implications: Deepen the understanding of each security aspect by explaining the potential vulnerabilities, attack vectors, and consequences of exploitation.
   • Infer Architecture and Data Flow: Based on the component function and interactions described, infer the relevant architectural details and data flow paths from a security perspective.
3. Threat Identification: Based on the component analysis, identify specific threats relevant to each component and the overall Ceph system.
4. Tailored Security Considerations Formulation: Consolidate the identified threats and security implications into a set of specific security considerations tailored to the Ceph distributed storage system.
5. Actionable Mitigation Strategy Development: For each security consideration, develop concrete, actionable, and Ceph-specific mitigation strategies. These strategies will be practical recommendations that the development team can implement to enhance Ceph security.
6. Documentation and Reporting: Document the entire analysis process, findings, security considerations, and mitigation strategies in a clear and structured report.

2. Security Implications of Key Components

2.1. Ceph Monitors (MONs) - Security Authority

• Function: Maintain cluster map, enforce authentication (Cephx), manage authorization (capabilities), crucial for cluster consensus and integrity.

• Key Security Aspects and Implications:

  • Authentication (Cephx Protocol):

    • Implication: Cephx is the cornerstone of Ceph security. Weaknesses in its implementation or configuration directly translate to unauthorized access. Replay attacks could allow attackers to reuse captured authentication tokens to impersonate legitimate users or daemons. Man-in-the-middle (MITM) attacks, if communication channels are not secured, could allow attackers to intercept credentials or modify communication, leading to authentication bypass or data manipulation. Time synchronization is critical; significant clock drift can cause valid authentication attempts to be rejected or, conversely, allow replay attacks to be successful for longer periods.
    • Specific Ceph Implication: Ceph daemons and clients rely heavily on Cephx for inter-component and client-to-cluster communication. A compromised Cephx implementation or misconfiguration can have widespread impact across the entire storage system.

  • Authorization (Capabilities):

    • Implication: Capabilities define the level of access granted to users and daemons. Overly permissive capabilities violate the principle of least privilege, increasing the attack surface. If a user or daemon with excessive capabilities is compromised, the attacker gains broad access to the Ceph cluster, potentially leading to data breaches, data corruption, or service disruption.
    • Specific Ceph Implication: Ceph's capability system is powerful but complex. Incorrectly configured capabilities, especially for administrative users or services, can lead to significant security vulnerabilities. Granular control and regular review of capabilities are essential.

  • Quorum & Consensus (Paxos/Raft):

    • Implication: The monitor quorum ensures cluster consistency and availability. DoS attacks targeting monitors to disrupt quorum formation can lead to cluster unavailability or split-brain scenarios. Compromise of a quorum majority grants an attacker complete control over the cluster, allowing them to manipulate cluster state, access data, and potentially render the entire system unusable.
    • Specific Ceph Implication: Ceph's reliance on a distributed consensus mechanism makes the monitor quorum a critical security target. Protecting monitors from DoS and unauthorized access is paramount for cluster stability and security.

  • Data Sensitivity (Cluster Map, Keys):

    • Implication: Monitors store highly sensitive data, including the cluster map (topology, state) and Cephx secret keys. Unauthorized access to this data is catastrophic. Exposure of the cluster map can reveal valuable information about the infrastructure to attackers. Compromise of Cephx keys allows for complete authentication bypass and impersonation.
    • Specific Ceph Implication: The RocksDB database used by monitors to store cluster state and keys becomes a high-value target. Access control to the underlying storage and processes of monitors must be extremely strict. Encryption at rest for monitor data is crucial to protect against physical breaches or compromised storage.

  • Communication Security:

    • Implication: Unsecured communication between monitors and other daemons (OSDs, MGRs, MDSs) allows for MITM attacks, data tampering, and eavesdropping. Attackers could intercept and modify cluster commands, potentially disrupting operations or gaining unauthorized access.
    • Specific Ceph Implication: Ceph's distributed nature relies on extensive inter-daemon communication. Securing these communication channels using cephx_require_signatures, cephx_cluster_require_signatures, and cephx_service_require_signatures is essential to maintain cluster integrity and prevent unauthorized manipulation.

  • Vulnerability to Clock Drift:

    • Implication: Cephx's time-sensitive nature makes it vulnerable to clock drift. Significant clock drift can lead to authentication failures for legitimate users and services, disrupting operations. In some scenarios, it could potentially weaken replay attack defenses if time synchronization is severely compromised.
    • Specific Ceph Implication: Accurate time synchronization across all Ceph nodes is a fundamental security requirement. Proper NTP configuration and monitoring are crucial to prevent authentication issues and maintain Cephx security.

2.2. Ceph Managers (MGRs) - Management & Monitoring Exposure

• Function: Management interface (dashboard, API), monitoring data aggregation, module hosting.

• Key Security Aspects and Implications:

  • Management Interface Security (Dashboard, REST API):

    • Implication: Web interfaces are inherently vulnerable to common web application attacks. XSS vulnerabilities can allow attackers to inject malicious scripts into the dashboard, potentially stealing credentials or performing actions on behalf of administrators. CSRF vulnerabilities can allow attackers to trick administrators into performing unintended actions. Injection vulnerabilities (e.g., command injection, SQL injection if applicable) can allow attackers to execute arbitrary code on the MGR server.
    • Specific Ceph Implication: The Ceph dashboard and REST API provide administrative access to the cluster. Compromising these interfaces can grant attackers full control over the Ceph system. Secure coding practices, regular security audits, and penetration testing of the management interface are critical.

  • Module Security:

    • Implication: MGR modules extend Ceph functionality but can also introduce vulnerabilities if not developed and vetted securely. Third-party or custom modules may contain security flaws that could be exploited to compromise the MGR or the entire cluster.
    • Specific Ceph Implication: Ceph's modular architecture allows for extensibility, but it also necessitates careful module management. Modules should be sourced from trusted locations, undergo security reviews, and be regularly updated to patch vulnerabilities. A robust module vetting process is essential.

  • Access Control (Management API):

    • Implication: Weak access control to the management API can allow unauthorized users to perform administrative actions. Lack of RBAC can lead to privilege escalation and unauthorized modifications to the cluster configuration. Insufficient authentication mechanisms (e.g., weak passwords, no MFA) can make it easier for attackers to gain access.
    • Specific Ceph Implication: The management API provides powerful administrative capabilities. Strict RBAC implementation, strong authentication (including MFA), and regular access reviews are crucial to protect the management plane.

  • Data Sensitivity (Monitoring Data, Configuration):

    • Implication: Monitoring data and cluster configuration information, while not directly user data, can still be sensitive. Exposure of monitoring data can reveal performance metrics, cluster topology, and potential weaknesses to attackers. Configuration data can expose security policies and settings.
    • Specific Ceph Implication: Access to monitoring data and configuration should be restricted to authorized personnel. While not as critical as user data, this information can aid attackers in reconnaissance and planning attacks.

  • Communication Security:

    • Implication: Unsecured communication between MGRs and MONs/OSDs can allow for tampering with management operations. Attackers could intercept and modify management commands, potentially disrupting cluster operations or gaining unauthorized control.
    • Specific Ceph Implication: MGRs play a crucial role in cluster management. Securing communication channels between MGRs and other daemons is essential to maintain the integrity of management operations and prevent unauthorized interference.

  • API Rate Limiting & DoS Protection:

    • Implication: Management APIs, if not protected, are vulnerable to DoS attacks. Attackers can flood the API with requests, overwhelming the MGR and potentially disrupting management operations or even impacting cluster stability.
    • Specific Ceph Implication: The Ceph management API is a critical service. Implementing rate limiting, connection limits, and potentially using a Web Application Firewall (WAF) in front of the management interface can help mitigate DoS risks.

2.3. Ceph Object Storage Devices (OSDs) - Data at Rest & Integrity

• Function: Store data objects, handle replication, recovery, scrubbing, data migration.

• Key Security Aspects and Implications:

  • Data at Rest Encryption (dm-crypt, BlueStore Encryption):

    • Implication: Lack of data at rest encryption leaves data vulnerable to physical theft of storage media or unauthorized access to the underlying storage. If disks are stolen or decommissioned improperly, sensitive data can be exposed.
    • Specific Ceph Implication: Ceph OSDs store the actual user data. Data at rest encryption is a fundamental security control for protecting data confidentiality. Implementing dm-crypt or BlueStore encryption is crucial. However, secure key management is equally important. Weak key management can render encryption ineffective. Keys must be protected from unauthorized access and managed securely throughout their lifecycle.

  • Data Integrity (Checksums, Scrubbing):

    • Implication: Data corruption, whether due to hardware failures, software bugs, or malicious activity, can lead to data loss or inconsistencies. Without integrity checks, silent data corruption can go undetected, leading to long-term data degradation and potential application failures.
    • Specific Ceph Implication: Ceph's distributed and replicated nature makes data integrity paramount. Checksums and scrubbing are essential mechanisms for detecting and mitigating data corruption. Regular scrubbing should be configured and monitored to ensure data integrity is maintained.

  • Access Control (Capabilities Enforcement):

    • Implication: OSDs are responsible for enforcing access control based on capabilities granted by MONs. Vulnerabilities in capability enforcement on OSDs can lead to unauthorized data access, even if authentication and authorization are correctly implemented at the monitor level.
    • Specific Ceph Implication: OSD-level capability enforcement is a critical security layer. Bugs or vulnerabilities in the OSD capability enforcement logic could bypass intended access controls and allow unauthorized data access. Rigorous testing and security audits of OSD code are necessary.

  • Process Isolation & Sandboxing:

    • Implication: If OSD processes are not properly isolated, vulnerabilities in one OSD process could potentially be exploited to compromise other OSD processes or even the underlying host system. Lack of sandboxing can increase the impact of vulnerabilities.
    • Specific Ceph Implication: Ceph OSDs are complex processes handling sensitive data. Process isolation and sandboxing techniques (e.g., using containers, namespaces, seccomp) can limit the blast radius of potential OSD vulnerabilities and enhance overall security.

  • Communication Security:

    • Implication: Unsecured OSD-to-OSD and OSD-to-MON communication can expose data replication and recovery processes to interception and tampering. Attackers could potentially inject malicious data during replication or disrupt recovery operations.
    • Specific Ceph Implication: OSD communication is critical for data replication, recovery, and cluster health. Securing OSD communication channels is essential to maintain data integrity and prevent unauthorized manipulation of these processes.

  • Resource Exhaustion & DoS:

    • Implication: OSDs can be targeted by DoS attacks to exhaust resources (CPU, disk I/O, network). Attackers could flood OSDs with requests, causing performance degradation, service disruption, or even OSD crashes, impacting cluster availability and data access.
    • Specific Ceph Implication: OSDs are the workhorses of the Ceph cluster. Protecting OSDs from resource exhaustion attacks is crucial for maintaining cluster performance and availability. Rate limiting, connection limits, and network security measures can help mitigate DoS risks.

2.4. Ceph Metadata Servers (MDSs) - CephFS Security & Availability

• Function: Manage metadata for CephFS, provide POSIX-compliant file system access.

• Key Security Aspects and Implications:

  • Metadata Security (Permissions, Attributes):

    • Implication: Metadata stores critical access control information for CephFS, including POSIX permissions and file attributes. Compromise of MDS or vulnerabilities in metadata handling can lead to unauthorized access to CephFS data, bypassing intended access controls.
    • Specific Ceph Implication: MDS is the gatekeeper for CephFS access. Robust metadata security is paramount for CephFS security. Vulnerabilities in MDS metadata handling or access control logic can have severe consequences for data confidentiality and integrity within CephFS.

  • Access Control (POSIX Permissions, Ceph Capabilities):

    • Implication: MDS enforces POSIX permissions and Ceph capabilities for CephFS access. Misconfigurations in permissions or vulnerabilities in capability enforcement can lead to security breaches, allowing unauthorized users to access or modify files and directories within CephFS.
    • Specific Ceph Implication: Correctly configuring and enforcing POSIX permissions and Ceph capabilities within CephFS is crucial. Regular audits of CephFS permissions and capability configurations are necessary to prevent misconfigurations and security breaches.

  • Performance & Availability (DoS Target):

    • Implication: MDS performance is critical for CephFS responsiveness. DoS attacks targeting MDS can render CephFS unusable, even if the underlying data on OSDs remains intact. MDS availability is essential for CephFS functionality.
    • Specific Ceph Implication: MDS is a single point of failure for CephFS metadata operations. Protecting MDS from DoS attacks and ensuring high availability through redundancy and load balancing are crucial for CephFS service continuity.

  • Communication Security:

    • Implication: Unsecured communication between MDS and MONs, OSDs, and clients can expose metadata operations and data access to interception and tampering. Attackers could potentially manipulate metadata, gain unauthorized access, or disrupt CephFS operations.
    • Specific Ceph Implication: Securing all communication channels involving MDS is essential to protect metadata integrity and prevent unauthorized access to CephFS data.

  • Metadata Injection Attacks:

    • Implication: Vulnerabilities in MDS metadata handling could potentially lead to metadata injection attacks. Attackers could inject malicious metadata, potentially compromising file system integrity, bypassing access controls, or even executing code on the MDS server.
    • Specific Ceph Implication: MDS must be robust against metadata injection attacks. Rigorous input validation and secure coding practices are essential in MDS development to prevent such vulnerabilities.

2.5. RADOS Gateways (RGWs) - API Security & External Exposure

• Function: S3/Swift API endpoints, translate API requests to RADOS operations.

• Key Security Aspects and Implications:

  • API Security (S3/Swift API Implementation):

    • Implication: RGWs, being web applications, are vulnerable to common web application vulnerabilities as defined by OWASP Top 10. These include injection flaws (SQL, command, code), broken authentication, sensitive data exposure, XSS, CSRF, security misconfigurations, insufficient logging and monitoring, etc.
    • Specific Ceph Implication: RGWs are often exposed to external networks, making them a prime target for web-based attacks. Secure API design, rigorous input validation, output encoding, regular security audits, and penetration testing are crucial for RGW security.

  • Authentication & Authorization (S3/Swift Authentication):

    • Implication: Weaknesses in S3/Swift authentication mechanisms or insecure handling of credentials (S3 keys, Swift tokens, IAM policies) can lead to unauthorized access to object storage. Vulnerabilities in authentication logic can allow attackers to bypass authentication entirely.
    • Specific Ceph Implication: RGW authentication mechanisms must be robust and securely implemented. Secure handling of S3 keys and Swift tokens, proper IAM policy enforcement, and regular security reviews of authentication logic are essential.

  • Access Control (Bucket/Object Policies, ACLs):

    • Implication: Misconfigurations in bucket and object-level access control policies or vulnerabilities in ACL enforcement can lead to data breaches, allowing unauthorized users to access or modify objects they should not have access to.
    • Specific Ceph Implication: RGW's access control mechanisms (bucket policies, ACLs) must be correctly configured and rigorously enforced. Regular audits of access control policies and testing of ACL enforcement are necessary to prevent data breaches.

  • Data in Transit Encryption (HTTPS/TLS):

    • Implication: Lack of HTTPS/TLS encryption for RGW API communication exposes data in transit to eavesdropping and MITM attacks. Sensitive data, including credentials and object data, can be intercepted if communication is not encrypted.
    • Specific Ceph Implication: HTTPS/TLS encryption is mandatory for all RGW API communication, especially when exposed to external networks. Proper TLS configuration, including strong cipher suites and certificate management, is essential.

  • Input Validation & Injection Prevention:

    • Implication: Insufficient input validation in RGW API handlers can lead to various injection attacks (SQL injection, command injection, etc.). Attackers could inject malicious payloads into API requests, potentially gaining unauthorized access, executing arbitrary code, or manipulating data.
    • Specific Ceph Implication: RGW API handlers must perform rigorous input validation on all API requests to prevent injection attacks. Secure coding practices and input sanitization are crucial.

  • DoS Protection (Rate Limiting, WAF):

    • Implication: RGWs, being internet-facing, are highly susceptible to DoS and DDoS attacks. Attackers can flood RGW APIs with requests, overwhelming the gateway and potentially disrupting object storage services.
    • Specific Ceph Implication: RGWs must be protected against DoS attacks. Implementing rate limiting, connection limits, and deploying a Web Application Firewall (WAF) in front of RGWs are essential mitigation strategies.

  • SSRF (Server-Side Request Forgery):

    • Implication: RGW functionalities that interact with external resources (e.g., object replication to external storage, webhook notifications) can be vulnerable to SSRF attacks. Attackers could potentially abuse these functionalities to make RGW initiate requests to internal resources or external systems, potentially gaining unauthorized access or performing malicious actions.
    • Specific Ceph Implication: RGW functionalities involving external interactions must be carefully reviewed for SSRF vulnerabilities. Input validation, output sanitization, and network segmentation can help mitigate SSRF risks.

2.6. LibRados & Client Libraries - Client-Side Vulnerabilities

• Function: Direct RADOS access for applications.

• Key Security Aspects and Implications:

  • Client-Side Security Vulnerabilities:

    • Implication: Applications using LibRados or other Ceph client libraries can introduce vulnerabilities if not developed securely. Common client-side vulnerabilities include buffer overflows, format string bugs, memory leaks, and insecure coding practices. These vulnerabilities can be exploited to compromise the client application or even the Ceph cluster if the client has sufficient privileges.
    • Specific Ceph Implication: Client applications are often the entry point to the Ceph cluster. Secure coding practices, regular security audits, and penetration testing of client applications are essential to prevent client-side vulnerabilities from compromising the Ceph system.

  • Authentication & Authorization Handling (Client-Side):

    • Implication: Clients must securely handle Ceph authentication credentials (keys, capabilities). Hardcoding credentials in client code or insecure storage of keys (e.g., in plaintext configuration files) is a major security risk. If client credentials are compromised, attackers can gain unauthorized access to the Ceph cluster.
    • Specific Ceph Implication: Client applications should never hardcode Ceph credentials. Secure credential management practices, such as using environment variables, configuration files with restricted permissions, or dedicated secret management systems, must be implemented.

  • Input Validation (Client-Side):

    • Implication: Client applications should validate user inputs before sending requests to Ceph. Lack of client-side input validation can make applications vulnerable to injection attacks (e.g., command injection, path traversal) if user inputs are directly passed to Ceph API calls without proper sanitization.
    • Specific Ceph Implication: Client-side input validation is a defense-in-depth measure. Validating user inputs at the client level can prevent malicious payloads from reaching the Ceph cluster and potentially triggering vulnerabilities.

  • Dependency Management (Client Libraries):

    • Implication: Client libraries (LibRados, RBD, CephFS clients) and their dependencies can contain vulnerabilities. If client libraries are not regularly updated and vulnerability scanned, applications using them can inherit these vulnerabilities, potentially compromising application and Ceph cluster security.
    • Specific Ceph Implication: Regularly updating client libraries and scanning them for vulnerabilities is crucial. A robust dependency management process should be in place to ensure client libraries are kept up-to-date with security patches.

3. Tailored Security Considerations for Ceph

Based on the component analysis, the following are tailored security considerations for a Ceph distributed storage system:

1. Cephx Protocol Security: Ensure robust configuration and secure implementation of the Cephx authentication protocol. Address potential vulnerabilities like replay attacks, MITM attacks, and time synchronization issues.
2. Granular Capability Management: Implement and enforce granular capabilities based on the principle of least privilege. Regularly review and audit capability assignments to prevent excessive access rights.
3. Monitor Quorum Protection: Secure Ceph monitors and the quorum mechanism against DoS attacks and unauthorized access. Implement redundancy and network security measures to protect monitor availability and integrity.
4. Monitor Data Encryption and Access Control: Encrypt monitor data at rest and enforce strict access control to monitor data and processes. Protect sensitive information like cluster maps and Cephx keys.
5. Secure Inter-Daemon Communication: Mandate and enforce secure communication channels (using cephx_require_signatures, etc.) for all inter-daemon communication (MONs, MGRs, OSDs, MDSs) to prevent tampering and eavesdropping.
6. Management Interface Hardening: Secure the Ceph management interface (dashboard, API) against web application vulnerabilities (OWASP Top 10). Implement strong authentication (MFA), RBAC, input validation, and regular security audits.
7. MGR Module Vetting and Security: Establish a rigorous vetting process for MGR modules, especially third-party or custom modules. Ensure modules are developed securely and regularly updated with security patches.
8. Data at Rest Encryption for OSDs: Implement data at rest encryption for Ceph OSDs using dm-crypt or BlueStore encryption. Securely manage encryption keys using a robust key management system.
9. Data Integrity Verification: Enable and regularly monitor data integrity mechanisms (checksums, scrubbing) on OSDs to detect and mitigate data corruption.
10. OSD Process Isolation and Sandboxing: Implement process isolation and sandboxing for OSD processes to limit the impact of potential vulnerabilities and enhance security.
11. MDS Metadata Security and Access Control: Ensure robust metadata security and access control within CephFS. Protect metadata integrity and prevent unauthorized access to CephFS data through MDS vulnerabilities.
12. RGW API Security Best Practices: Implement web application security best practices for RGW APIs, including input validation, output encoding, secure authentication and authorization, and DoS protection.
13. RGW Data in Transit Encryption: Mandate HTTPS/TLS encryption for all RGW API communication, especially for external access. Configure TLS securely with strong cipher suites and proper certificate management.
14. Client-Side Security Awareness and Practices: Educate developers on secure coding practices for Ceph client applications. Emphasize secure credential handling, input validation, and dependency management.
15. Regular Security Audits and Penetration Testing: Conduct regular security audits and penetration testing of the entire Ceph infrastructure, including all components and access methods, to identify and remediate security weaknesses proactively.
16. Incident Response Planning for Ceph: Develop and maintain a specific incident response plan for security incidents affecting the Ceph cluster, outlining procedures for detection, containment, eradication, recovery, and post-incident analysis.

4. Actionable and Tailored Mitigation Strategies

For each security consideration, here are actionable and tailored mitigation strategies applicable to Ceph:

1. Cephx Protocol Security:

   • Action:
     • Enforce cephx_require_signatures, cephx_cluster_require_signatures, cephx_service_require_signatures to true in ceph.conf to mandate signed messages for all Cephx communication.
     • Implement NTP synchronization across all Ceph nodes and monitor for clock drift.
     • Regularly rotate Cephx keys using ceph auth rotate command.
     • Consider using secure channels (e.g., IPsec or WireGuard) for inter-daemon communication for enhanced confidentiality and integrity, especially in untrusted network environments.

2. Granular Capability Management:

   • Action:
     • Adopt the principle of least privilege when granting capabilities. Grant only the necessary permissions for each user, application, or daemon.
     • Utilize fine-grained capabilities (e.g., pool-level, namespace-level, object-level capabilities) instead of broad permissions.
     • Regularly review and audit capability assignments using ceph auth list and ceph auth get commands.
     • Implement automated capability management workflows to streamline provisioning and revocation based on roles and responsibilities.

3. Monitor Quorum Protection:

   • Action:
     • Deploy monitors in a physically and logically separate, protected network zone.
     • Implement firewall rules to restrict access to monitor ports (default 6789, 3300) only from authorized daemons and management hosts.
     • Configure monitor quorum size appropriately (typically odd number, e.g., 3 or 5) for fault tolerance and resilience against DoS attacks.
     • Implement rate limiting and connection limits on monitor ports to mitigate DoS attempts.
     • Monitor monitor health and quorum status using Ceph monitoring tools and alerts.

4. Monitor Data Encryption and Access Control:

   • Action:
     • Enable encryption at rest for the RocksDB database used by monitors using operating system-level encryption (e.g., dm-crypt on the underlying volume).
     • Restrict file system permissions on monitor data directories to only the ceph user and group.
     • Implement process isolation for monitor processes using containers or namespaces.
     • Regularly audit access logs for monitor processes and data directories.

5. Secure Inter-Daemon Communication:

   • Action:
     • Verify that cephx_require_signatures, cephx_cluster_require_signatures, cephx_service_require_signatures are set to true in ceph.conf across all nodes.
     • Monitor Ceph logs for warnings or errors related to Cephx signature verification failures.
     • Consider enabling encryption for inter-daemon communication using ms_cluster_mode = secure and ms_service_mode = secure in ceph.conf (requires TLS configuration).
     • If using TLS, ensure proper certificate management and strong cipher suite configuration.

6. Management Interface Hardening:

   • Action:
     • Enable HTTPS for the Ceph dashboard and REST API.
     • Implement strong authentication mechanisms for the dashboard and API, including multi-factor authentication (MFA) if possible.
     • Enforce Role-Based Access Control (RBAC) for management API access, granting users only the necessary permissions.
     • Regularly update the Ceph dashboard and MGR modules to patch known vulnerabilities.
     • Conduct regular security audits and penetration testing of the management interface.
     • Deploy a Web Application Firewall (WAF) in front of the management interface to protect against common web attacks.
     • Implement rate limiting and connection limits on the management API to mitigate DoS attacks.

7. MGR Module Vetting and Security:

   • Action:
     • Establish a policy for vetting and approving MGR modules before deployment.
     • Source modules from trusted repositories and vendors.
     • Conduct security reviews and code audits of MGR modules, especially custom or third-party modules.
     • Regularly update MGR modules to patch known vulnerabilities.
     • Implement module isolation if possible to limit the impact of vulnerabilities in one module on other MGR components.

8. Data at Rest Encryption for OSDs:

   • Action:
     • Choose and implement a data at rest encryption method (dm-crypt or BlueStore encryption) during Ceph deployment or configuration.
     • Develop a robust key management strategy for encryption keys. Consider using dedicated key management systems (KMS) for secure key storage and rotation.
     • Ensure proper key lifecycle management, including key generation, distribution, rotation, and revocation.
     • Regularly test data recovery procedures with encryption enabled to ensure functionality.

9. Data Integrity Verification:

   • Action:
     • Enable checksumming for data objects in Ceph pools.
     • Configure regular scrubbing schedules for Ceph pools using ceph osd pool set <pool-name> scrub_min_interval and ceph osd pool set <pool-name> scrub_max_interval.
     • Monitor scrubbing logs and alerts for any detected data corruption.
     • Implement automated repair processes for detected data corruption if possible.

10. OSD Process Isolation and Sandboxing:

    • Action:
      • Deploy OSDs in containers (e.g., Docker, Podman) to provide process isolation and resource limits.
      • Utilize Linux namespaces and cgroups for OSD process isolation if not using containers.
      • Implement seccomp profiles to restrict system calls available to OSD processes, reducing the attack surface.
      • Apply SELinux or AppArmor policies to further restrict OSD process capabilities and access.

11. MDS Metadata Security and Access Control:

    • Action:
      • Regularly review and audit CephFS permissions and capability configurations.
      • Implement access control lists (ACLs) for CephFS to provide fine-grained access control.
      • Secure communication channels between MDS and clients, MONs, and OSDs.
      • Implement input validation and sanitization in MDS code to prevent metadata injection attacks.
      • Deploy redundant MDS instances for high availability and to mitigate DoS risks.
      • Monitor MDS performance and resource utilization to detect potential DoS attacks.

12. RGW API Security Best Practices:

    • Action:
      • Implement rigorous input validation for all RGW API requests to prevent injection attacks.
      • Use parameterized queries or prepared statements if database interactions are involved in RGW.
      • Encode output data to prevent XSS vulnerabilities.
      • Implement secure session management and prevent session fixation attacks.
      • Regularly update RGW software to patch known vulnerabilities.
      • Conduct regular security audits and penetration testing of RGW APIs.
      • Implement rate limiting and connection limits on RGW APIs to mitigate DoS attacks.
      • Deploy a Web Application Firewall (WAF) in front of RGWs to protect against common web attacks.

13. RGW Data in Transit Encryption:

    • Action:
      • Enable HTTPS for RGW API endpoints.
      • Configure TLS with strong cipher suites and disable weak or deprecated ciphers.
      • Use valid TLS certificates issued by a trusted Certificate Authority (CA).
      • Enforce HTTPS redirection to ensure all communication is encrypted.
      • Regularly renew and manage TLS certificates.

14. Client-Side Security Awareness and Practices:

    • Action:
      • Provide security awareness training to developers on secure coding practices for Ceph client applications.
      • Develop secure coding guidelines for Ceph client applications, emphasizing secure credential handling, input validation, and dependency management.
      • Promote the use of secure credential management methods (environment variables, secure configuration files, KMS) instead of hardcoding credentials.
      • Encourage client-side input validation to prevent injection attacks.
      • Implement dependency scanning and vulnerability management for client libraries and their dependencies.

15. Regular Security Audits and Penetration Testing:

    • Action:
      • Schedule regular security audits of the Ceph infrastructure, including configuration reviews, code audits, and vulnerability assessments.
      • Conduct penetration testing of the Ceph cluster, simulating real-world attack scenarios to identify vulnerabilities.
      • Engage external security experts to perform independent security assessments.
      • Remediate identified vulnerabilities promptly based on risk prioritization.
      • Track and document security audit and penetration testing findings and remediation efforts.

16. Incident Response Planning for Ceph: * Action:

    • Develop a comprehensive incident response plan specifically for Ceph security incidents.
    • Define roles and responsibilities for incident response team members.
    • Establish procedures for incident detection, containment, eradication, recovery, and post-incident analysis.
    • Integrate Ceph logs with a SIEM system for centralized security monitoring and incident detection.
    • Conduct regular incident response drills and tabletop exercises to test and improve the plan.
    • Maintain up-to-date contact information for security incident reporting and escalation.

5. Conclusion

This deep security analysis of the Ceph distributed storage system, based on the provided design review document, has identified key security considerations and proposed actionable mitigation strategies tailored to Ceph's architecture and components. By implementing these recommendations, the development team can significantly enhance the security posture of their Ceph deployment, mitigating potential threats and ensuring a more secure and resilient storage infrastructure. Continuous security monitoring, regular audits, and proactive vulnerability management are essential to maintain a strong security posture for Ceph in the long term. This analysis should serve as a starting point for ongoing security efforts and should be revisited and updated as Ceph evolves and new threats emerge.