
* Fix code formatting, fix for memory leak in validate_handshake_reply_token and make error handling and return values more consistent with the other two plugins. Signed-off-by: Dennis Potman <dennis.potman@adlinktech.com> * Processed review comments: fixed memory leaks and more consistent error handling and function returns Signed-off-by: Dennis Potman <dennis.potman@adlinktech.com> * Fix trusted ca dir max exceeded Signed-off-by: Dennis Potman <dennis.potman@adlinktech.com>
801 lines
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ReStructuredText
801 lines
37 KiB
ReStructuredText
.. _`DDS Security`:
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############
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DDS Security
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############
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CycloneDDS is compliant with The Object Management Group (OMG) DDS Security specification.
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This specification defines the Security Model and Service Plugin Interface (SPI) architecture for
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compliant DDS implementations. The DDS Security Model is enforced by the invocation of these SPIs
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by the DDS implementation.
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.. image:: ./_static/pictures/dds_security_overview.png
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:width: 1000
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The three plugins that comprise the DDS Security Model in CycloneDDS are:
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**Authentication Service Plugin**
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Provides the means to verify the identity of the application and/or user that invokes operations
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on DDS. Includes facilities to perform mutual authentication between participants and establish
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a shared secret.
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**AccessControl Service Plugin**
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Provides the means to enforce policy decisions on what DDS related operations an authenticated
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user can perform. For example, which domains it can join, which Topics it can publish or
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subscribe to, etc.
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**Cryptographic Service Plugin**
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Implements (or interfaces with libraries that implement) all cryptographic operations including
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encryption, decryption, hashing, digital signatures, etc. This includes the means to derive keys
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from a shared secret.
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----
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CycloneDDS provides built-in implementations of these plugins. Authentication uses PKI
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(Public Key Infrastructure) with a pre-configured shared Certificate Authority, RSA is used for
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authentication and Diffie-Hellman is used for key exchange. AccessControl use Permissions document
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signed by shared Certificate Authority. Cryptography uses AES-GCM (AES using Galois Counter Mode)
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for encryption and AES-GMAC for message authentication.
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Security plugins are dynamically loaded where the locations are defined in CycloneDDS
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configuration or Participant QoS settings.
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*******************************************************
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Brief information about PKI (public key infrastructure)
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*******************************************************
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The comprehensive system required to provide public-key encryption and digital signature services
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is known as a public-key infrastructure (PKI). The purpose of a PKI is to manage keys and
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certificates. By managing keys and certificates through a PKI, an organization establishes and
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maintains a trustworthy networking environment.
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Public Key Cryptography: Each user has a key pair, generated during the initial certificate
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deployment process, that is comprised of a public key, which is shared, and a private key, which
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is not shared. Data is encrypted with the user’s public key and decrypted with their private key.
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Digital signatures, used for non-repudiation, authentication and data integrity, are also generated
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using public key cryptography.
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**Identity Certificate**
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This is an electronic document used to prove the ownership of a public key. The certificate
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includes information about the key, information about the identity of its owner (called the
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subject), and the digital signature of an entity that has verified the certificate's contents
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(called the issuer). If the signature is valid, and the software examining the certificate
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trusts the issuer, then it can use that key to communicate securely with the certificate's
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subject.
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**Certificate Authority**
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This issues user certificates and acts as the chief agent of trust. When issuing a certificate
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to a user, the CA signs the certificate with its private key in order to validate it. During
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electronic transactions the CA also confirms that certificates are still valid. Certificates
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may be revoked for various reasons. For example, a user may leave the organization or they may
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forget their secret passphrase, the certificate may expire or become corrupt. This process is
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usually accomplished through the use of a Certificate Revocation List (CRL) which is a list of
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the certificates that have been revoked. Only the certificates that have been revoked appear on
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this list.
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**Subject of Identity Certificate**
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This is the identity to be secured. It contains information such as common name (CN),
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organization (OU), state (ST) and country (C).
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**Subject Name**
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This is aka distinguished name and is the string representation of certificate subject.
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ie: emailAddress=alice\@adlink.ist,CN=Alice,OU=IST,O=ADLink,ST=OV,C=NL
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*************************
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PKI Usage in DDS Security
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*************************
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.. image:: ./_static/pictures/pki_overview.png
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:width: 1000
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Alice and Bob are the DDS participants who have their private and public keys. Identitity
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Certificate Authority (ID CA) has its own self-signed certificate (IdentityCA in the diagram).
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ID CA gets Alice's subject information and public key and generates an IdentityCertificate for her.
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Alice's certificate includes her public key and certificate of ID CA; so that her certificate can
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be verified if it is really issued by ID CA.
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Access Control is configured with governance and permissions files. Governance file defines the
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security behavior of domains and topics. Permissions file contains the permissions of the domain
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participant, topics, readers and writers, binds them to identity certificate by subject name
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(distinguished name).
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Governance files and Permissions files are signed by Permission CA. Signed documents also
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contains Permissions CA certificate; so that they can be verified if they are really issued
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by Permissions CA.
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Authenticated participants perform a handshake with each other and generate a shared key by
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Diffie-Hellman key exchange. This shared key is used for encrypting/decrypting data with AES.
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During the handshake Alice checks Bob's certificate and Bob's Permissions file if they are really
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issued by the ID CA certificate and Permissions CA Certificate that **she** has. Also Bob checks
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Alice's certificate and Alice's Permissions file if they are really issued by the ID CA certificate
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and Permissions CA that **he** has.
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Permissions files can contain permissions for several identities; so subject name of identity
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certificate exist in permissions file to establish a binding between identity and its permissions.
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There are several ways to set up the certificates and signed configuration files to be used with
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Cyclone DDS Security. One of them is using OpenSSL, which is described in section
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`Creating certificates using OpenSSL`_.
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*************
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Configuration
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*************
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.. image:: ./_static/pictures/dds_security_configuration_overview.png
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:width: 1000
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The configuration of DDS Security is split up into two parts.
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- `Plugins Configuration`_
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- `Access Control Configuration`_
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Plugins Configuration
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*********************
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CycloneDDS gets the security configuration from XML configuration elements or from
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the participant QoS policies as stated in the DDS Security specification.
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This behavior allows applications to use DDS Security without recompiling the binaries.
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Only supplying a new configuration with DDS Security enabled is enough to switch from a
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non-secure to a secure deployment. The configuration is at domain level, which means
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that all participants created for that domain receive the same DDS security settings.
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The configuration options for a domain are bundled in the ``DDSSecurity`` configuration
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section in the CycloneDDS configuration. Every DDS Security plugin has its own configuration
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sub-section.
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.. _`Authentication Properties`:
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=========================
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Authentication Properties
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=========================
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To enable authentication for a node, it has to be configured with an identity certificate
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(``DDSSecurity/Authentication/IdentityCertificate``). This identity certificate is used to
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authenticate all participants of that particular CycloneDDS domain. Associated with the
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identity certificate is the corresponding private key
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(``DDSSecurity/Authentication/PrivateKey``). The private key may either be a 2048-bit RSA
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or a 256-bit Elliptic Curve Key with a prime256v1 curve.
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The certificate of identity CA, which is the issuer of the node's identity certificate,
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is configured in ``DDSSecurity/Authentication/IdentityCA``. The public key of the
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identity CA (as part of its certificate) shall either be a 2048-bit RSA key or a 256-bit
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Elliptic Curve Key for the prime256v1 curve. The identity CA certificate can be a
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self-signed certificate.
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The identity certificate, private key and the identity CA should be a X509 document in PEM
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format. It may either be specified directly in the configuration file (as CDATA, prefixed
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with ``data:,``) or the configuration file should contain a reference to a corresponding
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file (prefixed with ``file:``).
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Optionally the private key could be protected by a password
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(``DDSSecurity/Authentication/Password``).
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Furthermore the CycloneDDS configuration allows configuring a directory containing additional
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identity CA's which are used to verify the identity certificates that are received from remote instances
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(``DDSSecurity/Authentication/TrustedCADirectory``). This option allows multiple identity
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CAs throughout the system.
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.. _`Access Control Properties`:
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=========================
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Access Control Properties
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=========================
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A governance document (``DDSSecurity/AccessControl/Governance``), a permissions document
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(``DDSSecurity/AccessControl/Permissions``) and the permissions CA certificate
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(``DDSSecurity/AccessControl/PermissionsCA``) are required for the access control plugin.
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Similar to the authentication plugin properties, these values can be provided as CDATA or
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by using a path to a file.
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.. _`Cryptography Properties`:
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=======================
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Cryptography Properties
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=======================
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The cryptography plugin has no properties in the configuration.
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.. _`Access Control Configuration`:
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Access Control Configuration
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****************************
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Access Control configuration consists of Governance document and Permissions document.
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Both governance and permissions files must be signed by the Permissions CA in S/MIME format.
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Participants use their own permissions CA to validate remote permissions. So, all permissions CA
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Certificates must be the same for all participants.
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The signed document should use S/MIME version 3.2 format as defined in IETF RFC 5761 using
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SignedData Content Type (section 2.4.2 of IETF RFC 5761) formatted as multipart/signed (section
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3.4.3 of IETF RFC 5761). This corresponds to the mime-type application/pkcs7-signature.
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Additionally the signer certificate should be be included within the signature.
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===================
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Governance Document
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===================
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The Governance document defines the security behavior of domains and topics. It is an XML document
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and its format is specified in OMG DDS Security Version 1.1 Section 9.4.1.2.3.
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This section describes the properties that can be specified in a permissions document. An example
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of a governance document is provided in `Create a signed governance document`_. The options
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that are specified in Governance document must match with the remote node to establishing
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communication.
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Protection Kinds
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================
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The domain governance document provides a means for the application to configure the kinds of
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cryptographic transformation applied to the complete RTPS Message, certain RTPS SubMessages, and
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the SerializedPayload RTPS submessage element that appears within the Data.
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.. image:: ./_static/pictures/rtps_message_structure.png
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:width: 300
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The configuration allows specification of five protection levels: NONE, SIGN, ENCRYPT,
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SIGN_WITH_ORIGIN_AUTHENTICATION and ENCRYPT_WITH_ORIGIN_AUTHENTICATION.
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**NONE**
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indicates no cryptographic transformation is applied.
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**SIGN**
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indicates the cryptographic transformation shall be purely a message authentication code (MAC),
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that is, no encryption is performed.
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**ENCRYPT**
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indicates the cryptographic transformation shall be an encryption followed by a message
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authentication code (MAC) computed on the ciphertext, also known as Encrypt-then-MAC.
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**SIGN_WITH_ORIGIN_AUTHENTICATION**
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indicates the cryptographic transformation shall be purely a set of message authentication codes
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(MAC), that is, no encryption is performed. This cryptographic transformation shall create a
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first “common authenticationcode” similar to the case where Protection Kind is SIGN. In addition
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the cryptographic transformation shall create additional authentication codes, each produced with
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a different secret key. The additional MACs prove to the receiver that the sender originated the
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message, preventing other receivers from impersonating the sender.
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**ENCRYPT_WITH_ORIGIN_AUTHENTICATION**
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indicates the cryptographic transformation shall be an encryption followed by a message
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authentication code (MAC) computed on the ciphertext, followed by additional authentication
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codes, Each of the additional authentication codes shall use a different secret key. The
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encryption and first (common) authentication code is similar to ones produced when the Protection
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Kind is ENCRYPT. The additional authentication codes are similar to the ones produced when the
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Protection Kind is SIGN_WITH_ORIGIN_AUTHENTICATION.
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Participant attributes
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======================
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**Allow Unauthenticated Participants**
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This is used for allowing communication with non-secure participants. If this option is enabled,
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secure participant can communicate with non-secure participant by only non-protected topics.
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**Enable Join Access Control**
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If this option is enabled, remote participant permissions are checked if its subject name is
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allowed to create a topic anyhow.
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**Discovery Protection Kind**
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Protection attribute for discovery communication when it is enabled for topic. Please see the
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DDS Security specification document for available options.
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**Liveliness Protection Kind**
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Protection attribute for liveliness communication when it is enabled for topic. Please see the
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DDS Security specification document for available options.
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**RTPS Protection Kind**
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Protection attribute for all messages on the wire. Please see the DDS Security specification
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document for available options. If encryption is selected for RTPS, there is no need to encrypt
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submessages (metadata_protection_kind) and payloads (data_protection_kind) which are defined in
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topic settings.
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Topic Attributes
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================
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**Enable Discovery protection:**
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If enabled, discovery is protected according to Discovery Protection Kind attribute of
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corresponding participant.
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**Enable Liveliness protection:**
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If enabled, liveliness is protected according to Liveliness Protection Kind attribute of
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corresponding participant.
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**Enable Read Access Control:**
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If enabled, the permissions document is checked if the participant is allowed to create
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a datareader for the related topic.
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**Enable Write Access Control:**
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If enabled, the permissions document is checked if the participant is allowed to create
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a datawriter for the related topic.
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**Metadata protection Kind:**
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Protection attribute for submessages.
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**Data protection Kind:**
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Protection attribute for data payload.
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There are different settings for different domain ranges. The domain rules are evaluated in the
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same order as they appear in the document. A rule only applies to a particular DomainParticipant
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if the domain Section matches the DDS domain_id to which the participant belongs. If multiple
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rules match, the first rule that matches is the only one that applies.
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The topic access rules are evaluated in the same order as they appear within the
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<topic_access_rules> Section. If multiple rules match the first rule that matches is the only one
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that applies.
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fnmatch pattern matching can be used for topic expressions including the following patterns
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.. _`fnmatch pattern matching`:
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+----------+----------------------------------+
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|Pattern |Meaning |
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+==========+==================================+
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| \* | matches everything |
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+----------+----------------------------------+
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| \? | matches any single character |
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+----------+----------------------------------+
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| [seq] | matches any character in seq |
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+----------+----------------------------------+
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| [!seq] | matches any character not in seq |
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+----------+----------------------------------+
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====================
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Permissions Document
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====================
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The permissions document is an XML document containing the permissions of the domain participant
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and binding them to the subject name of the DomainParticipant as defined in the identity
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certificate. Its format is specified in OMG DDS Security Version 1.1 Section 9.4.1.3.
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This section describes the properties that can be specified in a permissions document. An example
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of a permissions document is provided in `Creating a signed permissions document`_.
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Validity period
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===============
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It is checked before creating participant. Validity period is also checked during handshake with
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remote participant; expired remote permissions document prevents communications to be established.
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Subject Name
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============
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The subject name must match with Identity Certificate subject. It is checked during create
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participant and during handshake with remote participant. Use the following openssl command to get
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subject name from identity certificate:
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``openssl x509 -noout -subject -nameopt RFC2253 -in <identity_certificate_file.pem>``
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Rules
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=====
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Participant permissions are defined by set of rules. The rules are applied in the same order
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that appear in the document. If the criteria for the rule matches the domain_id join and/or publish
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or subscribe operation that is being attempted, then the allow or deny decision is applied.
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If the criteria for a rule does not match the operation being attempted, the evaluation
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shall proceed to the next rule. If all rules have been examined without a match, then the
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decision specified by the “default” rule is applied. The default rule, if present, must
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appear after all allow and deny rules. If the default rule is not present, the
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implied default decision is DENY. The matching criteria for each rule specify the domain_id,
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topics (published and subscribed), the partitions (published and subscribed), and the data-tags
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associated with the DataWriter and DataReader.
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For the grant to match there shall be a match of the topics, partitions, and data-tags criteria.
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This is interpreted as an AND of each of the criteria. For a specific criterion to match
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(e.g., <topics>) it is enough that one of the topic expressions listed matches (i.e., an OR of
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the expressions with the <topics> section).
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`fnmatch pattern matching`_ can be used for topic expressions and partition expressions.
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Logging and tracing
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*******************
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The security implementation uses the standard logging and tracing mechanism in CycloneDDS.
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The following is written to log and trace:
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- Configuration errors such as plugin library files, certificate files, governance and permissions
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files that can not be found on filesystem.
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- Permission errors such as denied permission for creating writer of a topic.
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- Attribute mismatch errors such as mismatches of security attributes between participants, topics,
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readers and writers.
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- Integrity errors such as Permissions file-Permissions CA and Identity Cert-Identity CA integrity.
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Local subscription, publication and topic permission errors are written as errors.
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Remote participation, subscription and publication permission errors are written to log as
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warning messages.
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Data Communication And Handshake Process
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****************************************
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Authentication handshake between participants starts after participant discovery. If a reader and
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a writer created during that period, their match will be delayed until after the handshake succeeds.
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This means, during the handshake process, volatile data will be lost, just like there is no reader.
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After publication match, the encryption / decryption keys are exchanged between reader and writer.
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Best-effort data that are sent during this exchange will be lost, however reliable data will be
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resent.
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DDS Secure Discovery
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********************
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Just like normal operation, Cyclone DDS discovers remote participants, topics, readers and writers.
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However, when DDS Security is enabled, it is more complex and will take a longer time (due to the
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handshaking that is required). The effort to perform discovery grows quadratically in the number of
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nodes. This can become a problem if the system contains a number of slow platforms or is large.
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Proprietary builtin endpoints
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*****************************
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The DDS standard contains some builtin endpoints. A few are added by the DDS Security
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specification. The behaviour of all these builtin endpoints are specified (and thus are be
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handled by the plugins that implement the DDS Security specification), meaning that they
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don't have to be present in the Governance or Permissions documents and the users don't
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have to be bothered with them.
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A few of these builtin endpoints slave according to the <discovery_protection_kind> within
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the Governance document. In short, related submessages are protected according to the value
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of <discovery_protection_kind>. This protects meta information that is send during the
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discovery phase.
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*******************
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DataTag Permissions
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*******************
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Data Tags provide an extra (optional) level of identification. This can mean f.i. that
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a certain reader is not allowed to read data from writer A but it is allowed to read from
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writer B (all the same topic).
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This optional feature is not yet supported.
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.. _`Example configuration`:
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*********************
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Example configuration
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*********************
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This sections show an example configuration for DDS Security in Cyclone DDS. First step is
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creating the required CA and identity certificates. Then a governance and permissions document
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is created to configure access control. Next an example configuration (XML) that
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is using these assets is shown, and a code fragment that shows how to set the security
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properties by using the participant QoS.
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.. _`Creating certificates using OpenSSL`:
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Creating certificates using OpenSSL
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***********************************
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This section describes how to generate a set of CA and identity certificates using OpenSSL,
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and how to use OpenSSL to sign the governance and access control configuration files.
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First step is generation of the CA for identity management (authentication). First we create the
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private key for the CA by:
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.. code-block:: bash
|
||
|
||
openssl genrsa -out example_id_ca_priv_key.pem 2048
|
||
|
||
Next we can generate the certificate for the identity CA (which is in this case a self-signed
|
||
certificate):
|
||
|
||
.. code-block:: bash
|
||
|
||
openssl req -x509 -key example_id_ca_priv_key.pem -out example_id_ca_cert.pem -days 3650 -subj "/C=NL/ST=OV/L=Locality Name/OU=Example OU/O=Example ID CA Organization/CN=Example ID CA/emailAddress=authority@cycloneddssecurity.adlinktech.com"
|
||
|
||
We repeat these steps for generating the private key of the permissions CA (used for
|
||
signing the AccessControl configiguration files):
|
||
|
||
.. code-block:: bash
|
||
|
||
openssl genrsa -out example_perm_ca_priv_key.pem 2048
|
||
|
||
And the self-signed certificate for the permissions CA:
|
||
|
||
.. code-block:: bash
|
||
|
||
openssl req -x509 -key example_perm_ca_priv_key.pem -out example_perm_ca_cert.pem -days 3650 -subj "/C=NL/ST=OV/L=Locality Name/OU=Example OU/O=Example CA Organization/CN=Example Permissions CA/emailAddress=authority@cycloneddssecurity.adlinktech.com"
|
||
|
||
==============================
|
||
Create an Identity Certificate
|
||
==============================
|
||
|
||
Now that we have set up the CA for identity management, we can create an identity certificate
|
||
signed by this CA and the private key corresponding to this identity. Here we are creating
|
||
a private key and certificate for identity named Alice. These steps need to be repeated for each
|
||
identity in the system.
|
||
|
||
Generating the private key for Alice's identity:
|
||
|
||
.. code-block:: bash
|
||
|
||
openssl genrsa -out example_alice_priv_key.pem 2048
|
||
|
||
Now we create a 'certificate signing request' (CSR) to request the identity CA to generate a certificate:
|
||
|
||
.. code-block:: bash
|
||
|
||
openssl req -new -key example_alice_priv_key.pem -out example_alice.csr -subj "/C=NL/ST=OV/L=Locality Name/OU=Organizational Unit Name/O=Example Organization/CN=Alice Example/emailAddress=alice@cycloneddssecurity.adlinktech.com"
|
||
|
||
Next Alice's identity certificate is created:
|
||
|
||
.. code-block:: bash
|
||
|
||
openssl x509 -req -CA example_id_ca_cert.pem -CAkey example_id_ca_priv_key.pem -CAcreateserial -days 3650 -in example_alice.csr -out example_alice_cert.pem
|
||
|
||
|
||
Now the file 'example_alice_cert.pem' can be used as ``IdentityCertificate`` in the DDS Security
|
||
authentication configuration and 'example_alice_priv_key.pem' for the ``PrivateKey`` setting. The
|
||
certificate of the CA used for signing this identity, 'example_id_ca_cert.pem' in this example,
|
||
should be used for the ``IdentityCA`` configuration setting.
|
||
|
||
|
||
.. _`Create a signed governance document`:
|
||
|
||
===================================
|
||
Create a signed governance document
|
||
===================================
|
||
|
||
An example of a governance document that is using signing for submessage and encrypted payload:
|
||
|
||
.. literalinclude:: _static/example_governance.xml
|
||
:linenos:
|
||
:language: xml
|
||
|
||
As mentioned before, the governance document needs to be signed by the permissions CA
|
||
that was created above. This can be done by using this openssl command:
|
||
|
||
.. code-block:: bash
|
||
|
||
openssl smime -sign -in example_governance.xml -text -out example_governance.p7s -signer example_perm_ca_cert.pem -inkey example_perm_ca_priv_key.pem
|
||
|
||
|
||
.. _`Creating a signed permissions document`:
|
||
|
||
======================================
|
||
Creating a signed permissions document
|
||
======================================
|
||
|
||
The permissions document is an XML document that contains the permissions of the participant and
|
||
binds them to the subject name of the identity certificate (distinguished name) for the participant
|
||
as defined in the DDS:Auth:PKI-DH authentication plugin.
|
||
|
||
An example of a permissions document:
|
||
|
||
.. literalinclude:: _static/example_permissions.xml
|
||
:linenos:
|
||
:language: xml
|
||
|
||
This document also needs to be signed by the permissions CA:
|
||
|
||
.. code-block:: bash
|
||
|
||
openssl smime -sign -in example_permissions.xml -text -out example_permissions.p7s -signer example_perm_ca_cert.pem -inkey example_perm_ca_priv_key.pem
|
||
|
||
|
||
Example DDS Security configuration
|
||
**********************************
|
||
|
||
With the above steps we have all certificates and documents that are required when configuring
|
||
security. In the next two sections, both configuring security by properties and configuring
|
||
security by DDS configuration are covered.
|
||
|
||
======================================
|
||
Security properties in participant QoS
|
||
======================================
|
||
|
||
This code fragment shows how to set the security properties to a QoS object and use this QoS
|
||
when creating a participant:
|
||
|
||
.. literalinclude:: _static/security_by_qos.c
|
||
:linenos:
|
||
:language: c
|
||
|
||
|
||
===========================================
|
||
Configure security in Cyclone configuration
|
||
===========================================
|
||
|
||
As an alternative for using the QoS, security settings can also be applied using the CycloneDDS
|
||
configuration XML. In case both QoS and the configuration XML contain security settings, the values
|
||
from the QoS will be used and the security settings in the configuration XML are ignored.
|
||
|
||
The following XML fragment shows how to set security settings through configuration:
|
||
|
||
.. literalinclude:: _static/security_by_config.xml
|
||
:linenos:
|
||
:language: xml
|
||
|
||
To use this configuration file for an application, set the CYCLONEDDS_URI environment
|
||
variable to this config file:
|
||
|
||
.. code-block:: bash
|
||
|
||
export CYCLONEDDS_URI=/path/to/secure_config.xml
|
||
|
||
Bacause this example configuration uses the attribute ``id=any`` for the ``domain`` element, any participant
|
||
that is created (which implicitly creates a domain) in an application using this configuration gets
|
||
these security settings.
|
||
|
||
***************************
|
||
External Plugin Development
|
||
***************************
|
||
|
||
DDS Security consists of three plugins (authentication, cryptography and access control).
|
||
CycloneDDS comes with built-in security plugins that comply with OMG DDS Security specification.
|
||
The plugins are loaded in the run-time. However, you can also implement your own custom plugin by
|
||
implementing the given API according to OMG DDS Security specification.
|
||
You can implement all of the plugins or just one of them.
|
||
|
||
The followings are the key points for implementing you own plugin:
|
||
|
||
|
||
Interface
|
||
*********
|
||
|
||
Implement all plugin specific functions with exactly same prototype. Plugin specific function
|
||
interfaces are in dds_security_api_access_control.h, dds_security_api_authentication.h and
|
||
dds_security_api_cryptography.h header files accordingly.
|
||
|
||
|
||
Init and Finalize
|
||
*****************
|
||
|
||
A plugin should have an init and a finalize functions. plugin_init and plugin_finalize
|
||
interfaces are given in dds_security_api.h header file and function should be same as in
|
||
configuration file.
|
||
Init function is called once, just after the plugin is loaded. Finalize function is
|
||
called once, just before the plugin is unloaded.
|
||
|
||
Inter Plugin Communication
|
||
**************************
|
||
|
||
There is a shared object (*DDS_Security_SharedSecretHandle*) within authentication and
|
||
cryptography plugins. If you want to implement only one of them and use the builtin for the
|
||
other one, you have to get or provide the shared object properly.
|
||
*DDS_Security_SharedSecretHandle* is the integer representation of
|
||
*DDS_Security_SharedSecretHandleImpl* struct object. Cryptography plugin gets the
|
||
*DDS_Security_SharedSecretHandle* from authentication plugin and casts to
|
||
*DDS_Security_SharedSecretHandleImpl* struct. Then all needed information can be retieved
|
||
through *DDS_Security_SharedSecretHandleImpl* struct:
|
||
|
||
::
|
||
|
||
typedef struct DDS_Security_SharedSecretHandleImpl {
|
||
DDS_Security_octet* shared_secret;
|
||
DDS_Security_long shared_secret_size;
|
||
DDS_Security_octet challenge1[DDS_SECURITY_AUTHENTICATION_CHALLENGE_SIZE];
|
||
DDS_Security_octet challenge2[DDS_SECURITY_AUTHENTICATION_CHALLENGE_SIZE];
|
||
|
||
} DDS_Security_SharedSecretHandleImpl;
|
||
|
||
|
||
Error Codes
|
||
***********
|
||
|
||
Most of the plugin functions have parameter for reporting exception. The following exception
|
||
codes should be used in the reported exception data according to the situation.
|
||
dds_security_api_err.h header file contains the code and message constants.
|
||
|
||
+-------+----------------------------------------------------------------+
|
||
| Code | Message |
|
||
+=======+================================================================+
|
||
| 0 | (OK) |
|
||
+-------+----------------------------------------------------------------+
|
||
| 100 | Can not generate random data |
|
||
+-------+----------------------------------------------------------------+
|
||
| 110 | Identity empty |
|
||
+-------+----------------------------------------------------------------+
|
||
| 111 | Participant Crypto Handle empty |
|
||
+-------+----------------------------------------------------------------+
|
||
| 112 | Permission Handle empty |
|
||
+-------+----------------------------------------------------------------+
|
||
| 113 | Invalid Crypto Handle |
|
||
+-------+----------------------------------------------------------------+
|
||
| 114 | Invalid argument |
|
||
+-------+----------------------------------------------------------------+
|
||
| 115 | Invalid Crypto token |
|
||
+-------+----------------------------------------------------------------+
|
||
| 116 | Invalid parameter |
|
||
+-------+----------------------------------------------------------------+
|
||
| 117 | File could not be found, opened or is empty, path: %s |
|
||
+-------+----------------------------------------------------------------+
|
||
| 118 | Unknown or unexpected transformation kind |
|
||
+-------+----------------------------------------------------------------+
|
||
| 119 | Message cannot be authenticated, incorrect signature |
|
||
+-------+----------------------------------------------------------------+
|
||
| 120 | Can not open trusted CA directory |
|
||
+-------+----------------------------------------------------------------+
|
||
| 121 | Identity CA is not trusted |
|
||
+-------+----------------------------------------------------------------+
|
||
| 122 | Certificate start date is in the future |
|
||
+-------+----------------------------------------------------------------+
|
||
| 123 | Certificate expired |
|
||
+-------+----------------------------------------------------------------+
|
||
| 125 | Certificate authentication algorithm unknown |
|
||
+-------+----------------------------------------------------------------+
|
||
| 126 | Failed to allocate internal structure |
|
||
+-------+----------------------------------------------------------------+
|
||
| 127 | Failed to parse PKCS7 SMIME document |
|
||
+-------+----------------------------------------------------------------+
|
||
| 128 | Property is missing: (%s) |
|
||
+-------+----------------------------------------------------------------+
|
||
| 129 | Permissions document is invalid |
|
||
+-------+----------------------------------------------------------------+
|
||
| 130 | Governance document is invalid |
|
||
+-------+----------------------------------------------------------------+
|
||
| 131 | Operation is not permitted in this state |
|
||
+-------+----------------------------------------------------------------+
|
||
| 132 | Remote permissions document is not available |
|
||
+-------+----------------------------------------------------------------+
|
||
| 133 | Certificate is invalid |
|
||
+-------+----------------------------------------------------------------+
|
||
| 134 | Certificate type is not supported |
|
||
+-------+----------------------------------------------------------------+
|
||
| 135 | Governance property is required |
|
||
+-------+----------------------------------------------------------------+
|
||
| 136 | Permissions CA property is required |
|
||
+-------+----------------------------------------------------------------+
|
||
| 137 | Can not parse governance file |
|
||
+-------+----------------------------------------------------------------+
|
||
| 138 | Can not parse permissions file |
|
||
+-------+----------------------------------------------------------------+
|
||
| 139 | Could not find permissions for topic |
|
||
+-------+----------------------------------------------------------------+
|
||
| 140 | Could not find domain %d in permissions |
|
||
+-------+----------------------------------------------------------------+
|
||
| 141 | Could not find domain %d in governance |
|
||
+-------+----------------------------------------------------------------+
|
||
| 142 | Could not find %s topic attributes for domain(%d) in governance|
|
||
+-------+----------------------------------------------------------------+
|
||
| 143 | PluginClass in remote token is incompatible |
|
||
+-------+----------------------------------------------------------------+
|
||
| 144 | MajorVersion in remote token is incompatible |
|
||
+-------+----------------------------------------------------------------+
|
||
| 145 | Access denied by access control |
|
||
+-------+----------------------------------------------------------------+
|
||
| 146 | Subject name is invalid |
|
||
+-------+----------------------------------------------------------------+
|
||
| 147 | Permissions validity period expired for %s |
|
||
+-------+----------------------------------------------------------------+
|
||
| 148 | Permissions validity period has not started yet for %s |
|
||
+-------+----------------------------------------------------------------+
|
||
| 149 | Could not find valid grant in permissions |
|
||
+-------+----------------------------------------------------------------+
|
||
| 150 | Unsupported URI type: %s |
|
||
+-------+----------------------------------------------------------------+
|
||
| 151 | The payload is not aligned at 4 bytes |
|
||
+-------+----------------------------------------------------------------+
|
||
| 152 | Cannot open trusted CA directory: maximum number exceeded |
|
||
+-------+----------------------------------------------------------------+
|
||
| 200 | Undefined Error Message |
|
||
+-------+----------------------------------------------------------------+
|
||
|
||
.. EoF
|