module ietf-constrained-voucher-request { yang-version 1.1; namespace "urn:ietf:params:xml:ns:yang:ietf-constrained-voucher-request"; prefix "constrained"; import ietf-restconf { prefix rc; description "This import statement is only present to access the yang-data extension defined in RFC 8040."; reference "RFC 8040: RESTCONF Protocol"; } import ietf-voucher { prefix "v"; } organization "IETF ANIMA Working Group"; contact "WG Web: WG List: Author: Michael Richardson Author: Peter van der Stok Author: Panos Kampanakis "; description "This module defines the format for a voucher request, which is produced by a pledge to request a voucher. The voucher-request is sent to the potential owner's Registrar, which in turn sends the voucher request to the manufacturer or delegate (MASA). A voucher is then returned to the pledge, binding the pledge to the owner. This is a constrained version of the voucher-request present in draft-ietf-anima-bootstrap-keyinfra.txt. This version provides a very restricted subset appropriate for very constrained devices. In particular, it assumes that nonce-ful operation is always required, that expiration dates are rather weak, as no clocks can be assumed, and that the Registrar is identified by a pinned Raw Public Key. The key words 'MUST', 'MUST NOT', 'REQUIRED', 'SHALL', 'SHALL NOT', 'SHOULD', 'SHOULD NOT', 'RECOMMENDED', 'MAY', and 'OPTIONAL' in the module text are to be interpreted as described in RFC 2119."; revision "2019-08-01" { description "Initial version"; reference "RFC XXXX: Voucher Profile for Constrained Devices"; } rc:yang-data voucher-request-constrained-artifact { // YANG data template for a voucher. uses voucher-request-constrained-grouping; } // Grouping defined for future usage grouping voucher-request-constrained-grouping { description "Grouping to allow reuse/extensions in future work."; uses v:voucher-artifact-grouping { refine voucher/created-on { mandatory false; } refine voucher/pinned-domain-cert { mandatory false; } augment "voucher" { description "Base the constrained voucher-request upon the regular one"; leaf proximity-registrar-subject-public-key-info { type binary; description "The proximity-registrar-subject-public-key-info replaces the proximit-registrar-cert in constrained uses of the voucher-request. The proximity-registrar-subject-public-key-info is the Raw Public Key of the Registrar. This field is encoded as specified in RFC7250, section 3. The ECDSA algorithm MUST be supported. The EdDSA algorithm as specified in draft-ietf-tls-rfc4492bis-17 SHOULD be supported. Support for the DSA algorithm is not recommended. Support for the RSA algorithm is MAY, but due to size is discouraged."; } leaf proximity-registrar-sha256-of-subject-public-key-info { type binary; description "The proximity-registrar-sha256-of-subject-public-key-info is an alternative to proximity-registrar-subject-public-key-info. and pinned-domain-cert. In many cases the public key of the domain has already been transmitted during the key agreement protocol, and it is wasteful to transmit the public key another two times. The use of a hash of public key info, at 32-bytes for sha256 is a significant savings compared to an RSA public key, but is only a minor savings compared to a 256-bit ECDSA public-key. Algorithm agility is provided by extensions to this specifications which define new leaf for other hash types."; } leaf proximity-registrar-cert { type binary; description "An X.509 v3 certificate structure as specified by RFC 5280, Section 4 encoded using the ASN.1 distinguished encoding rules (DER), as specified in ITU-T X.690. The first certificate in the Registrar TLS server certificate_list sequence (see [RFC5246]) presented by the Registrar to the Pledge. This MUST be populated in a Pledge's voucher request if the proximity assertion is populated."; } leaf prior-signed-voucher-request { type binary; description "If it is necessary to change a voucher, or re-sign and forward a voucher that was previously provided along a protocol path, then the previously signed voucher SHOULD be included in this field. For example, a pledge might sign a proximity voucher, which an intermediate registrar then re-signs to make its own proximity assertion. This is a simple mechanism for a chain of trusted parties to change a voucher, while maintaining the prior signature information. The pledge MUST ignore all prior voucher information when accepting a voucher for imprinting. Other parties MAY examine the prior signed voucher information for the purposes of policy decisions. For example this information could be useful to a MASA to determine that both pledge and registrar agree on proximity assertions. The MASA SHOULD remove all prior-signed-voucher-request information when signing a voucher for imprinting so as to minimize the final voucher size."; } } } } }