Internet-Draft | BRSKI | January 2020 |
Pritikin, et al. | Expires 6 July 2020 | [Page] |
This document specifies automated bootstrapping of an Autonomic Control Plane. To do this a Secure Key Infrastructure is bootstrapped. This is done using manufacturer-installed X.509 certificates, in combination with a manufacturer's authorizing service, both online and offline. We call this process the Bootstrapping Remote Secure Key Infrastructure (BRSKI) protocol. Bootstrapping a new device can occur using a routable address and a cloud service, or using only link-local connectivity, or on limited/disconnected networks. Support for deployment models with less stringent security requirements is included. Bootstrapping is complete when the cryptographic identity of the new key infrastructure is successfully deployed to the device. The established secure connection can be used to deploy a locally issued certificate to the device as well.¶
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The Bootstrapping Remote Secure Key Infrastructure (BRSKI) protocol provides a solution for secure zero-touch (automated) bootstrap of new (unconfigured) devices that are called pledges in this document. Pledges have an IDevID installed in them at the factory.¶
"BRSKI" is pronounced like "brewski", a colloquial term for beer in Canada and parts of the US-midwest. [brewski]¶
This document primarily provides for the needs of the ISP and Enterprise focused ANIMA Autonomic Control Plane (ACP) [I-D.ietf-anima-autonomic-control-plane]. This bootstrap process satisfies the [RFC7575] requirements of section 3.3 of making all operations secure by default. Other users of the BRSKI protocol will need to provide separate applicability statements that include privacy and security considerations appropriate to that deployment. Section 9 explains the detailed applicability for this the ACP usage.¶
The BRSKI protocol requires a significant amount of communication between manufacturer and owner: in its default modes it provides a cryptographic transfer of control to the initial owner. In its strongest modes, it leverages sales channel information to identify the owner in advance. Resale of devices is possible, provided that the manufacturer is willing to authorize the transfer. Mechanisms to enable transfers of ownership without manufacturer authorization are not included in this version of the protocol, but could be designed into future versions.¶
This document describes how pledges discover (or are discovered by) an element of the network domain to which the pledge belongs that will perform the bootstrap. This element (device) is called the registrar. Before any other operation, pledge and registrar need to establish mutual trust:¶
This document details protocols and messages to answer the above questions. It uses a TLS connection and an PKIX-shaped (X.509v3) certificate (an IEEE 802.1AR [IDevID] IDevID) of the pledge to answer points 1 and 2. It uses a new artifact called a "voucher" that the registrar receives from a "Manufacturer Authorized Signing Authority" (MASA) and passes to the pledge to answer points 3 and 4.¶
A proxy provides very limited connectivity between the pledge and the registrar.¶
The syntactic details of vouchers are described in detail in [RFC8366]. This document details automated protocol mechanisms to obtain vouchers, including the definition of a 'voucher-request' message that is a minor extension to the voucher format (see Section 3) defined by [RFC8366].¶
BRSKI results in the pledge storing an X.509 root certificate sufficient for verifying the registrar identity. In the process a TLS connection is established that can be directly used for Enrollment over Secure Transport (EST). In effect BRSKI provides an automated mechanism for the "Bootstrap Distribution of CA Certificates" described in [RFC7030] Section 4.1.1 wherein the pledge "MUST [...] engage a human user to authorize the CA certificate using out-of-band" information. With BRSKI the pledge now can automate this process using the voucher. Integration with a complete EST enrollment is optional but trivial.¶
BRSKI is agile enough to support bootstrapping alternative key infrastructures, such as a symmetric key solutions, but no such system is described in this document.¶
To literally "pull yourself up by the bootstraps" is an impossible action. Similarly the secure establishment of a key infrastructure without external help is also an impossibility. Today it is commonly accepted that the initial connections between nodes are insecure, until key distribution is complete, or that domain-specific keying material (often pre-shared keys, including mechanisms like SIM cards) is pre-provisioned on each new device in a costly and non-scalable manner. Existing automated mechanisms are known as non-secured 'Trust on First Use' (TOFU) [RFC7435], 'resurrecting duckling' [Stajano99theresurrecting] or 'pre-staging'.¶
Another prior approach has been to try and minimize user actions during bootstrapping, but not eliminate all user-actions. The original EST protocol [RFC7030] does reduce user actions during bootstrap but does not provide solutions for how the following protocol steps can be made autonomic (not involving user actions):¶
These "touch" methods do not meet the requirements for zero-touch.¶
There are "call home" technologies where the pledge first establishes a connection to a well known manufacturer service using a common client-server authentication model. After mutual authentication, appropriate credentials to authenticate the target domain are transferred to the pledge. This creates several problems and limitations:¶
BRSKI addresses these issues by defining extensions to the EST protocol for the automated distribution of vouchers.¶
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in BCP 14 [RFC2119] [RFC8174] when, and only when, they appear in all capitals, as shown here.¶
The following terms are defined for clarity:¶
This solution (BRSKI) can support large router platforms with multi-gigabit inter-connections, mounted in controlled access data centers. But this solution is not exclusive to large equipment: it is intended to scale to thousands of devices located in hostile environments, such as ISP provided CPE devices which are drop-shipped to the end user. The situation where an order is fulfilled from distributed warehouse from a common stock and shipped directly to the target location at the request of a domain owner is explicitly supported. That stock ("SKU") could be provided to a number of potential domain owners, and the eventual domain owner will not know a-priori which device will go to which location.¶
The bootstrapping process can take minutes to complete depending on the network infrastructure and device processing speed. The network communication itself is not optimized for speed; for privacy reasons, the discovery process allows for the pledge to avoid announcing its presence through broadcasting.¶
Nomadic or mobile devices often need to acquire credentials to access the network at the new location. An example of this is mobile phone roaming among network operators, or even between cell towers. This is usually called handoff. BRSKI does not provide a low-latency handoff which is usually a requirement in such situations. For these solutions BRSKI can be used to create a relationship (an LDevID) with the "home" domain owner. The resulting credentials are then used to provide credentials more appropriate for a low-latency handoff.¶
Questions have been posed as to whether this solution is suitable in general for Internet of Things (IoT) networks. This depends on the capabilities of the devices in question. The terminology of [RFC7228] is best used to describe the boundaries.¶
The solution described in this document is aimed in general at non-constrained (i.e., class 2+ [RFC7228]) devices operating on a non-Challenged network. The entire solution as described here is not intended to be useable as-is by constrained devices operating on challenged networks (such as 802.15.4 Low-power Lossy Networks (LLN)s).¶
Specifically, there are protocol aspects described here that might result in congestion collapse or energy-exhaustion of intermediate battery powered routers in an LLN. Those types of networks should not use this solution. These limitations are predominately related to the large credential and key sizes required for device authentication. Defining symmetric key techniques that meet the operational requirements is out-of-scope but the underlying protocol operations (TLS handshake and signing structures) have sufficient algorithm agility to support such techniques when defined.¶
The imprint protocol described here could, however, be used by non-energy constrained devices joining a non-constrained network (for instance, smart light bulbs are usually mains powered, and speak 802.11). It could also be used by non-constrained devices across a non-energy constrained, but challenged network (such as 802.15.4). The certificate contents, and the process by which the four questions above are resolved do apply to constrained devices. It is simply the actual on-the-wire imprint protocol that could be inappropriate.¶
This document presumes that network access control has either already occurred, is not required, or is integrated by the proxy and registrar in such a way that the device itself does not need to be aware of the details. Although the use of an X.509 Initial Device Identity is consistent with IEEE 802.1AR [IDevID], and allows for alignment with 802.1X network access control methods, its use here is for pledge authentication rather than network access control. Integrating this protocol with network access control, perhaps as an Extensible Authentication Protocol (EAP) method (see [RFC3748]), is out-of-scope.¶
This document describes "bootstrapping" as the protocol used to obtain a local trust anchor. It is expected that this trust anchor, along with any additional configuration information subsequently installed, is persisted on the device across system restarts ("booting"). Bootstrapping occurs only infrequently such as when a device is transferred to a new owner or has been reset to factory default settings.¶
As a result of the protocol described herein, the bootstrapped devices have the Domain CA trust anchor in common. An end entity certificate has optionally been issued from the Domain CA. This makes it possible to securely deploy functionalities across the domain, e.g:¶
The major intended benefit is that it possible to use the credentials deployed by this protocol to secure the Autonomic Control Plane (ACP) ([I-D.ietf-anima-autonomic-control-plane]).¶
The BRSKI protocol can be used in a number of environments. Some of the options in this document are the result of requirements that are out of the ANI scope. This section defines the base requirements for ANI devices.¶
For devices that intend to become part of an Autonomic Network Infrastructure (ANI) ([I-D.ietf-anima-reference-model]) that includes an Autonomic Control Plane ([I-D.ietf-anima-autonomic-control-plane]), the BRSKI protocol MUST be implemented.¶
The pledge must perform discovery of the proxy as described in Section 4.1 using Generic Autonomic Signaling Protocol (GRASP)'s DULL [I-D.ietf-anima-grasp] M_FLOOD announcements.¶
Upon successfully validating a voucher artifact, a status telemetry MUST be returned. See Section 5.7.¶
An ANIMA ANI pledge MUST implement the EST automation extensions described in Section 5.9. They supplement the [RFC7030] EST to better support automated devices that do not have an end user.¶
The ANI Join Registrar Autonomic Service Agent (ASA) MUST support all the BRSKI and above listed EST operations.¶
All ANI devices SHOULD support the BRSKI proxy function, using circuit proxies over the ACP. (See Section 4.3)¶
The logical elements of the bootstrapping framework are described in this section. Figure 1 provides a simplified overview of the components.¶
We assume a multi-vendor network. In such an environment there could be a Manufacturer Service for each manufacturer that supports devices following this document's specification, or an integrator could provide a generic service authorized by multiple manufacturers. It is unlikely that an integrator could provide Ownership Tracking services for multiple manufacturers due to the required sales channel integrations necessary to track ownership.¶
The domain is the managed network infrastructure with a Key Infrastructure the pledge is joining. The domain provides initial device connectivity sufficient for bootstrapping through a proxy. The domain registrar authenticates the pledge, makes authorization decisions, and distributes vouchers obtained from the Manufacturer Service. Optionally the registrar also acts as a PKI Certification Authority.¶
The pledge goes through a series of steps, which are outlined here at a high level.¶
State descriptions for the pledge are as follows:¶
The pledge is now a member of, and can be managed by, the domain and will only repeat the discovery aspects of bootstrapping if it is returned to factory default settings.¶
This specification details integration with EST enrollment so that pledges can optionally obtain a locally issued certificate, although any Representational State Transfer (REST) (see [REST]) interface could be integrated in future work.¶
A voucher is a cryptographically protected artifact (using a digital signature) to the pledge device authorizing a zero-touch imprint on the registrar domain.¶
The format and cryptographic mechanism of vouchers is described in detail in [RFC8366].¶
Vouchers provide a flexible mechanism to secure imprinting: the pledge device only imprints when a voucher can be validated. At the lowest security levels the MASA can indiscriminately issue vouchers and log claims of ownership by domains. At the highest security levels issuance of vouchers can be integrated with complex sales channel integrations that are beyond the scope of this document. The sales channel integration would verify actual (legal) ownership of the pledge by the domain. This provides the flexibility for a number of use cases via a single common protocol mechanism on the pledge and registrar devices that are to be widely deployed in the field. The MASA services have the flexibility to leverage either the currently defined claim mechanisms or to experiment with higher or lower security levels.¶
Vouchers provide a signed but non-encrypted communication channel among the pledge, the MASA, and the registrar. The registrar maintains control over the transport and policy decisions, allowing the local security policy of the domain network to be enforced.¶
Pledge authentication and pledge voucher-request signing is via a PKIX-shaped certificate installed during the manufacturing process. This is the 802.1AR Initial Device Identifier (IDevID), and it provides a basis for authenticating the pledge during the protocol exchanges described here. There is no requirement for a common root PKI hierarchy. Each device manufacturer can generate its own root certificate. Specifically, the IDevID enables:¶
Section 7.2.13 (2009 edition) and section 8.10.3 (2018 edition) of [IDevID] discusses keyUsage and extendedKeyUsage extensions in the IDevID certificate. [IDevID] acknowledges that adding restrictions in the certificate limits applicability of these long-lived certificates. This specification emphasizes this point, and therefore RECOMMENDS that no key usage restrictions be included. This is consistent with [RFC5280] section 4.2.1.3, which does not require key usage restrictions for end entity certificates.¶
In the context of BRSKI, pledges have a 1:1 relationship with a "serial-number". This serial-number is used both in the "serial-number" field of voucher or voucher-requests (see Section 3) and in local policies on registrar or MASA (see Section 5).¶
The serialNumber field is defined in [RFC5280]. That specification allows for the field to be omitted if there is a good technical reason. IDevID certificates for use with this protocol are REQUIRED to include the "serialNumber" attribute with the device's unique serial number (from [IDevID] section 7.2.8, and [RFC5280] section 4.1.2.2's list of standard attributes).¶
The serialNumber field is used as follows by the pledge to build the "serial-number" that is placed in the voucher-request. In order to build it, the fields need to be converted into a serial-number of "type string".¶
An example of a printable form of the "serialNumber" field is provided in [RFC4519] section 2.31 ("WI-3005"). That section further provides equality and syntax attributes.¶
Due to the reality of existing device identity provisioning processes, some manufacturers have stored serial-numbers in other fields. Registrar's SHOULD be configurable, on a per-manufacturer basis, to look for serial-number equivalents in other fields.¶
As explained in Section 5.5 the Registrar MUST extract the serial-number again itself from the pledge's TLS certificate. It can consult the serial-number in the pledge-request if there are any possible confusion about the source of the serial-number.¶
This document defines a new PKIX non-critical certificate extension to carry the MASA URI. This extension is intended to be used in the IDevID certificate. The URI is represented as described in Section 7.4 of [RFC5280].¶
The URI provides the authority information. The BRSKI "/.well-known" tree ([RFC5785]) is described in Section 5.¶
A complete URI MAY be in this extension, including the 'scheme', 'authority', and 'path', The complete URI will typically be used in diagnostic or experimental situations. Typically, (and in consideration to constrained systems), this SHOULD be reduced to only the 'authority', in which case a scheme of "https://" ([RFC7230] section 2.7.3) and 'path' of "/.well-known/est" is to be assumed.¶
The registrar can assume that only the 'authority' is present in the extension, if there are no slash ("/") characters in the extension.¶
Section 7.4 of [RFC5280] calls out various schemes that MUST be supported, including LDAP, HTTP and FTP. However, the registrar MUST use HTTPS for the BRSKI-MASA connection.¶
The new extension is identified as follows:¶
The choice of id-pe is based on guidance found in Section 4.2.2 of [RFC5280], "These extensions may be used to direct applications to on-line information about the issuer or the subject". The MASA URL is precisely that: online information about the particular subject.¶
A representative flow is shown in Figure 4¶
On initial bootstrap, a new device (the pledge) uses a local service autodiscovery (GRASP or mDNS) to locate a join proxy. The join proxy connects the pledge to a local registrar (the JRC).¶
Having found a candidate registrar, the fledgling pledge sends some information about itself to the registrar, including its serial number in the form of a voucher request and its device identity certificate (IDevID) as part of the TLS session.¶
The registrar can determine whether it expected such a device to appear, and locates a MASA. The location of the MASA is usually found in an extension in the IDevID. Having determined that the MASA is suitable, the entire information from the initial voucher request (including device serial number) is transmitted over the internet in a TLS protected channel to the manufacturer, along with information about the registrar/owner.¶
The manufacturer can then apply policy based on the provided information, as well as other sources of information (such as sales records), to decide whether to approve the claim by the registrar to own the device; if the claim is accepted, a voucher is issued that directs the device to accept its new owner.¶
The voucher is returned to the registrar, but not immediately to the device -- the registrar has an opportunity to examine the voucher, the MASA's audit-logs, and other sources of information to determine whether the device has been tampered with, and whether the bootstrap should be accepted.¶
No filtering of information is possible in the signed voucher, so this is a binary yes-or-no decision. If the registrar accepts the voucher as a proper one for its device, the voucher is returned to the pledge for imprinting.¶
The voucher also includes a trust anchor that the pledge uses as representing the owner. This is used to successfully bootstrap from an environment where only the manufacturer has built-in trust by the device into an environment where the owner now has a PKI footprint on the device.¶
When BRSKI is followed with EST this single footprint is further leveraged into the full owner's PKI and a LDevID for the device. Subsequent reporting steps provide flows of information to indicate success/failure of the process.¶
The pledge is the device that is attempting to join. The pledge is assumed to talk to the Join Proxy using link-local network connectivity. In most cases, the pledge has no other connectivity until the pledge completes the enrollment process and receives some kind of network credential.¶
The join proxy provides HTTPS connectivity between the pledge and the registrar. A circuit proxy mechanism is described in Section 4. Additional mechanisms, including a CoAP mechanism and a stateless IPIP mechanism are the subject of future work.¶
The domain's registrar operates as the BRSKI-MASA client when requesting vouchers from the MASA (see Section 5.4). The registrar operates as the BRSKI-EST server when pledges request vouchers (see Section 5.1). The registrar operates as the BRSKI-EST server "Registration Authority" if the pledge requests an end entity certificate over the BRSKI-EST connection (see Section 5.9).¶
The registrar uses an Implicit Trust Anchor database for authenticating the BRSKI-MASA connection's MASA TLS Server Certificate. Configuration or distribution of trust anchors is out-of-scope for this specification.¶
The registrar uses a different Implicit Trust Anchor database for authenticating the BRSKI-EST connection's Pledge TLS Client Certificate. Configuration or distribution of the BRSKI-EST client trust anchors is out-of-scope of this specification. Note that the trust anchors in/excluded from the database will affect which manufacturers' devices are acceptable to the registrar as pledges, and can also be used to limit the set of MASAs that are trusted for enrollment.¶
The Manufacturer Service provides two logically separate functions: the Manufacturer Authorized Signing Authority (MASA) described in Section 5.5 and Section 5.6, and an ownership tracking/auditing function described in Section 5.7 and Section 5.8.¶
The Public Key Infrastructure (PKI) administers certificates for the domain of concern, providing the trust anchor(s) for it and allowing enrollment of pledges with domain certificates.¶
The voucher provides a method for the distribution of a single PKI trust anchor (as the "pinned-domain-cert"). A distribution of the full set of current trust anchors is possible using the optional EST integration.¶
The domain's registrar acts as an [RFC5272] Registration Authority, requesting certificates for pledges from the Key Infrastructure.¶
The expectations of the PKI are unchanged from EST [RFC7030]. This document does not place any additional architectural requirements on the Public Key Infrastructure.¶
Many devices when bootstrapping do not have knowledge of the current time. Mechanisms such as Network Time Protocols cannot be secured until bootstrapping is complete. Therefore bootstrapping is defined with a framework that does not require knowledge of the current time. A pledge MAY ignore all time stamps in the voucher and in the certificate validity periods if it does not know the current time.¶
The pledge is exposed to dates in the following five places: registrar certificate notBefore, registrar certificate notAfter, voucher created-on, and voucher expires-on. Additionally, CMS signatures contain a signingTime.¶
A pledge with a real time clock in which it has confidence, MUST check the above time fields in all certificates and signatures that it processes.¶
If the voucher contains a nonce then the pledge MUST confirm the nonce matches the original pledge voucher-request. This ensures the voucher is fresh. See Section 5.2.¶
[RFC5280] explains that long lived pledge certificates "SHOULD be assigned the GeneralizedTime value of 99991231235959Z" for the notAfter field.¶
Some deployed IDevID management systems are not compliant with the 802.1AR requirement for infinite lifetimes, and put in typical <= 3 year certificate lifetimes. Registrars SHOULD be configurable on a per-manufacturer basis to ignore pledge lifetimes when the pledge did not follow the RFC5280 recommendations.¶
There exist operationally open networks wherein devices gain unauthenticated access to the Internet at large. In these use cases the management domain for the device needs to be discovered within the larger Internet. The case where a device can boot and get access to larger Internet are less likely within the ANIMA ACP scope but may be more important in the future. In the ANIMA ACP scope, new devices will be quarantined behind a Join Proxy.¶
There are additionally some greenfield situations involving an entirely new installation where a device may have some kind of management uplink that it can use (such as via 3G network for instance). In such a future situation, the device might use this management interface to learn that it should configure itself to become the local registrar.¶
In order to support these scenarios, the pledge MAY contact a well known URI of a cloud registrar if a local registrar cannot be discovered or if the pledge's target use cases do not include a local registrar.¶
If the pledge uses a well known URI for contacting a cloud registrar a manufacturer-assigned Implicit Trust Anchor database (see [RFC7030]) MUST be used to authenticate that service as described in [RFC6125]. The use of a DNS-ID for validation is appropriate, and it may include wildcard components on the left-mode side. This is consistent with the human user configuration of an EST server URI in [RFC7030] which also depends on RFC6125.¶
The registrar needs to be able to contact a MASA that is trusted by the pledge in order to obtain vouchers. There are three mechanisms described:¶
The device's Initial Device Identifier (IDevID) will normally contain the MASA URL as detailed in Section 2.3. This is the RECOMMENDED mechanism.¶
It can be operationally difficult to ensure the necessary X.509 extensions are in the pledge's IDevID due to the difficulty of aligning current pledge manufacturing with software releases and development. As a final fallback the registrar MAY be manually configured or distributed with a MASA URL for each manufacturer. Note that the registrar can only select the configured MASA URL based on the trust anchor -- so manufacturers can only leverage this approach if they ensure a single MASA URL works for all pledges associated with each trust anchor.¶
Voucher-requests are how vouchers are requested. The semantics of the voucher-request are described below, in the YANG model.¶
A pledge forms the "pledge voucher-request", signs it with it's IDevID and submits it to the registrar.¶
The registrar in turn forms the "registrar voucher-request", signs it with it's Registrar keypair and submits it to the MASA.¶
The "proximity-registrar-cert" leaf is used in the pledge voucher-requests. This provides a method for the pledge to assert the registrar's proximity.¶
This network proximity results from the following properties in the ACP context: the pledge is connected to the Join Proxy (Section 4) using a Link-Local IPv6 connection. While the Join Proxy does not participate in any meaningful sense in the cryptography of the TLS connection (such as via a Channel Binding), the Registrar can observe that the connection is via the private ACP (ULA) address of the join proxy, and could not come from outside the ACP. The Pledge must therefore be at most one IPv6 Link-Local hop away from an existing node on the ACP.¶
Other users of BRSKI will need to define other kinds of assertions if the network proximity described above does not match their needs.¶
The "prior-signed-voucher-request" leaf is used in registrar voucher-requests. If present, it is the signed pledge voucher-request artifact. This provides a method for the registrar to forward the pledge's signed request to the MASA. This completes transmission of the signed "proximity-registrar-cert" leaf.¶
Unless otherwise signaled (outside the voucher-request artifact), the signing structure is as defined for vouchers, see [RFC8366].¶
A registrar MAY also retrieve nonceless vouchers by sending nonceless voucher-requests to the MASA in order to obtain vouchers for use when the registrar does not have connectivity to the MASA. No "prior-signed-voucher-request" leaf would be included. The registrar will also need to know the serial number of the pledge. This document does not provide a mechanism for the registrar to learn that in an automated fashion. Typically this will be done via scanning of bar-code or QR-code on packaging, or via some sales channel integration.¶
The following tree diagram illustrates a high-level view of a voucher-request document. The voucher-request builds upon the voucher artifact described in [RFC8366]. The tree diagram is described in [RFC8340]. Each node in the diagram is fully described by the YANG module in Section 3.4. Please review the YANG module for a detailed description of the voucher-request format.¶
This section provides voucher-request examples for illustration purposes. These examples show the JSON prior to CMS wrapping. JSON encoding rules specify that any binary content by base64 encoded ([RFC4648] section 4). The contents of the certificate have been elided to save space. For detailed examples, see Appendix C.2. These examples conform to the encoding rules defined in [RFC7951].¶
Following is a YANG [RFC7950] module formally extending the [RFC8366] voucher into a voucher-request.¶
This section is normative for uses with an ANIMA ACP. The use of the GRASP mechanism is part of the ACP. Other users of BRSKI will need to define an equivalent proxy mechanism, and an equivalent mechanism to configure the proxy.¶
The role of the proxy is to facilitate communications. The proxy forwards packets between the pledge and a registrar that has been provisioned to the proxy via full GRASP ACP discovery.¶
This section defines a stateful proxy mechanism which is referred to as a "circuit" proxy. This is a form of Application Level Gateway ([RFC2663] section 2.9).¶
The proxy does not terminate the TLS handshake: it passes streams of bytes onward without examination. A proxy MUST NOT assume any specific TLS version. Please see [RFC8446] section 9.3 for details on TLS invariants.¶
A Registrar can directly provide the proxy announcements described below, in which case the announced port can point directly to the Registrar itself. In this scenario the pledge is unaware that there is no proxying occurring. This is useful for Registrars which are servicing pledges on directly connected networks.¶
As a result of the proxy Discovery process in Section 4.1.1, the port number exposed by the proxy does not need to be well known, or require an IANA allocation.¶
During the discovery of the Registrar by the Join Proxy, the Join Proxy will also learn which kinds of proxy mechanisms are available. This will allow the Join Proxy to use the lowest impact mechanism which the Join Proxy and Registrar have in common.¶
In order to permit the proxy functionality to be implemented on the maximum variety of devices the chosen mechanism should use the minimum amount of state on the proxy device. While many devices in the ANIMA target space will be rather large routers, the proxy function is likely to be implemented in the control plane CPU of such a device, with available capabilities for the proxy function similar to many class 2 IoT devices.¶
The document [I-D.richardson-anima-state-for-joinrouter] provides a more extensive analysis and background of the alternative proxy methods.¶
The result of discovery is a logical communication with a registrar, through a proxy. The proxy is transparent to the pledge. The communication between the pledge and Join Proxy is over IPv6 Link-Local addresses.¶
To discover the proxy the pledge performs the following actions:¶
Once a proxy is discovered the pledge communicates with a registrar through the proxy using the bootstrapping protocol defined in Section 5.¶
While the GRASP M_FLOOD mechanism is passive for the pledge, the non-normative other methods (mDNS, and IPv4 methods) described in Appendix B are active. The pledge SHOULD run those methods in parallel with listening to for the M_FLOOD. The active methods SHOULD back-off by doubling to a maximum of one hour to avoid overloading the network with discovery attempts. Detection of change of physical link status (Ethernet carrier for instance) SHOULD reset the back off timers.¶
The pledge could discover more than one proxy on a given physical interface. The pledge can have a multitude of physical interfaces as well: a layer-2/3 Ethernet switch may have hundreds of physical ports.¶
Each possible proxy offer SHOULD be attempted up to the point where a valid voucher is received: while there are many ways in which the attempt may fail, it does not succeed until the voucher has been validated.¶
The connection attempts via a single proxy SHOULD exponentially back-off to a maximum of one hour to avoid overloading the network infrastructure. The back-off timer for each MUST be independent of other connection attempts.¶
Connection attempts SHOULD be run in parallel to avoid head of queue problems wherein an attacker running a fake proxy or registrar could perform protocol actions intentionally slowly. Connection attempts to different proxies SHOULD be sent with an interval of 3 to 5s. The pledge SHOULD continue to listen to for additional GRASP M_FLOOD messages during the connection attempts.¶
Each connection attempt through a distinct Join Proxy MUST have a unique nonce in the voucher-request.¶
Once a connection to a registrar is established (e.g. establishment of a TLS session key) there are expectations of more timely responses, see Section 5.2.¶
Once all discovered services are attempted (assuming that none succeeded) the device MUST return to listening for GRASP M_FLOOD. It SHOULD periodically retry any manufacturer-specific mechanisms. The pledge MAY prioritize selection order as appropriate for the anticipated environment.¶
A proxy uses the DULL GRASP M_FLOOD mechanism to announce itself. This announcement can be within the same message as the ACP announcement detailed in [I-D.ietf-anima-autonomic-control-plane].¶
The formal Concise Data Definition Language (CDDL) [RFC8610] definition is:¶
Here is an example M_FLOOD announcing a proxy at fe80::1, on TCP port 4443.¶
On a small network the Registrar MAY include the GRASP M_FLOOD announcements to locally connected networks.¶
The $transport-proto above indicates the method that the pledge-proxy-registrar will use. The TCP method described here is mandatory, and other proxy methods, such as CoAP methods not defined in this document are optional. Other methods MUST NOT be enabled unless the Join Registrar ASA indicates support for them in it's own announcement.¶
The use of CoAP to connect from pledge to registrar is out of scope for this document, and is described in future work. See [I-D.ietf-anima-constrained-voucher].¶
The registrar SHOULD announce itself so that proxies can find it and determine what kind of connections can be terminated.¶
The registrar announces itself using ACP instance of GRASP using M_FLOOD messages. A registrar may announce any convenient port number, including using a stock port 443. ANI proxies MUST support GRASP discovery of registrars.¶
The M_FLOOD is formatted as follows:¶
The formal CDDL definition is:¶
The M_FLOOD message MUST be sent periodically. The default period SHOULD be 60 seconds, the value SHOULD be operator configurable but SHOULD NOT be smaller than 60 seconds. The frequency of sending MUST be such that the aggregate amount of periodic M_FLOODs from all flooding sources cause only negligible traffic across the ACP.¶
Here are some examples of locators for illustrative purposes. Only the first one ($transport-protocol = 6, TCP) is defined in this document and is mandatory to implement.¶
locator1 = [O_IPv6_LOCATOR, fd45:1345::6789, 6, 443] locator2 = [O_IPv6_LOCATOR, fd45:1345::6789, 17, 5683] locator3 = [O_IPv6_LOCATOR, fe80::1234, 41, nil]¶
A protocol of 6 indicates that TCP proxying on the indicated port is desired.¶
Registrars MUST announce the set of protocols that they support. They MUST support TCP traffic.¶
Registrars MUST accept HTTPS/EST traffic on the TCP ports indicated.¶
Registrars MUST support ANI TLS circuit proxy and therefore BRSKI across HTTPS/TLS native across the ACP.¶
In the ANI, the Autonomic Control Plane (ACP) secured instance of GRASP ([I-D.ietf-anima-grasp]) MUST be used for discovery of ANI registrar ACP addresses and ports by ANI proxies. The TCP leg of the proxy connection between ANI proxy and ANI registrar therefore also runs across the ACP.¶
The pledge MUST initiate BRSKI after boot if it is unconfigured. The pledge MUST NOT automatically initiate BRSKI if it has been configured or is in the process of being configured.¶
BRSKI is described as extensions to EST [RFC7030]. The goal of these extensions is to reduce the number of TLS connections and crypto operations required on the pledge. The registrar implements the BRSKI REST interface within the same "/.well-known" URI tree as the existing EST URIs as described in EST [RFC7030] section 3.2.2. The communication channel between the pledge and the registrar is referred to as "BRSKI-EST" (see Figure 1).¶
The communication channel between the registrar and MASA is similarly described as extensions to EST within the same "/.well-known" tree. For clarity this channel is referred to as "BRSKI-MASA". (See Figure 1).¶
The MASA URI is "https://" authority "/.well-known/est".¶
BRSKI uses existing CMS message formats for existing EST operations. BRSKI uses JSON [RFC8259] for all new operations defined here, and voucher formats. In all places where a binary value must be carried in a JSON string, the use of base64 format ([RFC4648] section 4) is to be used, as per [RFC7951] section 6.6.¶
While EST section 3.2 does not insist upon use of HTTP persistent connections ([RFC7230] section 6.3), BRSKI-EST connections SHOULD use persistent connections. The intention of this guidance is to ensure the provisional TLS state occurs only once, and that the subsequent resolution of the provision state is not subject to a MITM attack during a critical phase.¶
If non-persistent connections are used, then both the pledge and the registrar MUST remember the certificates seen, and also sent for the first connection. They MUST check each subsequent connections for the same certificates, and each end MUST use the same certificates as well. This places a difficult restriction on rolling certificates on the Registrar.¶
Summarized automation extensions for the BRSKI-EST flow are:¶
The BRSKI-EST TLS connection can now be used for EST enrollment.¶
The extensions for a registrar (equivalent to EST server) are:¶
The pledge establishes the TLS connection with the registrar through the circuit proxy (see Section 4) but the TLS handshake is with the registrar. The BRSKI-EST pledge is the TLS client and the BRSKI-EST registrar is the TLS server. All security associations established are between the pledge and the registrar regardless of proxy operations.¶
Use of TLS 1.3 (or newer) is encouraged. TLS 1.2 or newer is REQUIRED on the Pledge side. TLS 1.3 (or newer) SHOULD be available on the Registrar server interface, and the Registrar client interface, but TLS 1.2 MAY be used. TLS 1.3 (or newer) SHOULD be available on the MASA server interface, but TLS 1.2 MAY be used.¶
Establishment of the BRSKI-EST TLS connection is as specified in EST [RFC7030] section 4.1.1 "Bootstrap Distribution of CA Certificates" [RFC7030] wherein the client is authenticated with the IDevID certificate, and the EST server (the registrar) is provisionally authenticated with an unverified server certificate. Configuration or distribution of the trust anchor database used for validating the IDevID certificate is out-of-scope of this specification. Note that the trust anchors in/excluded from the database will affect which manufacturers' devices are acceptable to the registrar as pledges, and can also be used to limit the set of MASAs that are trusted for enrollment.¶
The signatures in the certificate MUST be validated even if a signing key can not (yet) be validated. The certificate (or chain) MUST be retained for later validation.¶
A self-signed certificate for the Registrar is acceptable as the voucher can validate it upon successful enrollment.¶
The pledge performs input validation of all data received until a voucher is verified as specified in Section 5.6.1 and the TLS connection leaves the provisional state. Until these operations are complete the pledge could be communicating with an attacker.¶
The pledge code needs to be written with the assumption that all data is being transmitted at this point to an unauthenticated peer, and that received data, while inside a TLS connection, MUST be considered untrusted. This particularly applies to HTTP headers and CMS structures that make up the voucher.¶
A pledge that can connect to multiple Registrars concurrently SHOULD do so. Some devices may be unable to do so for lack of threading, or resource issues. Concurrent connections defeat attempts by a malicious proxy from causing a TCP Slowloris-like attack (see [slowloris]).¶
A pledge that can not maintain as many connections as there are eligible proxies will need to rotate among the various choices, terminating connections that do not appear to be making progress. If no connection is making progress after 5 seconds then the pledge SHOULD drop the oldest connection and go on to a different proxy: the proxy that has been communicated with least recently. If there were no other proxies discovered, the pledge MAY continue to wait, as long as it is concurrently listening for new proxy announcements.¶
When the pledge bootstraps it makes a request for a voucher from a registrar.¶
This is done with an HTTPS POST using the operation path value of "/.well-known/est/requestvoucher".¶
The pledge voucher-request Content-Type is:¶
Registrar implementations SHOULD anticipate future media types but of course will simply fail the request if those types are not yet known.¶
The pledge SHOULD include an [RFC7231] section 5.3.2 "Accept" header field indicating the acceptable media type for the voucher response. The "application/voucher-cms+json" media type is defined in [RFC8366] but constrained voucher formats are expected in the future. Registrars and MASA are expected to be flexible in what they accept.¶
The pledge populates the voucher-request fields as follows:¶
All other fields MAY be omitted in the pledge voucher-request.¶
An example JSON payload of a pledge voucher-request is in Section 3.3 Example 1.¶
The registrar confirms that the assertion is 'proximity' and that pinned 'proximity-registrar-cert' is the Registrar's certificate. If this validation fails, then there is an On-Path Attacker (MITM), and the connection MUST be closed after the returning an HTTP 401 error code.¶
The BRSKI-MASA TLS connection is a 'normal' TLS connection appropriate for HTTPS REST interfaces. The registrar initiates the connection and uses the MASA URL obtained as described in Section 2.8. The mechanisms in [RFC6125] SHOULD be used in authentication of the MASA using a DNS-ID that matches that which is found in the IDevID. Registrars MAY include a mechanism to override the MASA URL on a manufacturer-by-manufacturer basis, and within that override it is appropriate to provide alternate anchors. This will typically used by some vendors to establish explicit (or private) trust anchors for validating their MASA that is part of a sales channel integration.¶
Use of TLS 1.3 (or newer) is encouraged. TLS 1.2 or newer is REQUIRED. TLS 1.3 (or newer) SHOULD be available.¶
As described in [RFC7030], the MASA and the registrars SHOULD be prepared to support TLS client certificate authentication and/or HTTP Basic or Digest authentication. This connection MAY also have no client authentication at all.¶
Registrars SHOULD permit trust anchors to be pre-configured on a per-vendor(MASA) basis. Registrars SHOULD include the ability to configure a TLS ClientCertificate on a per-MASA basis, or to use no client certificate. Registrars SHOULD also permit HTTP Basic and Digest authentication to be configured.¶
The authentication of the BRSKI-MASA connection does not change the voucher-request process, as voucher-requests are already signed by the registrar. Instead, this authentication provides access control to the audit-log as described in Section 5.8.¶
Implementors are advised that contacting the MASA is to establish a secured API connection with a web service and that there are a number of authentication models being explored within the industry. Registrars are RECOMMENDED to fail gracefully and generate useful administrative notifications or logs in the advent of unexpected HTTP 401 (Unauthorized) responses from the MASA.¶
Providing per-customer options requires that the customer's registrar be uniquely identified. This can be done by any stateless method that HTTPS supports such as with HTTP Basic or Digest authentication (that is using a password), but the use of TLS Client Certificate authentication is RECOMMENDED.¶
Stateful methods involving API tokens, or HTTP Cookies, are not recommended.¶
It is expected that the setup and configuration of per-customer Client Certificates is done as part of a sales ordering process.¶
The use of public PKI (i.e. WebPKI) End-Entity Certificates to identify the Registrar is reasonable, and if done universally this would permit a MASA to identify a customers' Registrar simply by a FQDN.¶
The use of DANE records in DNSSEC signed zones would also permit use of a FQDN to identify customer Registrars.¶
A third (and simplest, but least flexible) mechanism would be for the MASA to simply store the Registrar's certificate pinned in a database.¶
A MASA without any supply chain integration can simply accept Registrars without any authentication, or can accept them on a blind Trust-on-First-Use basis as described in Section 7.4.2.¶
This document does not make a specific recommendation on how the MASA authenticates the Registrar as there are likely different tradeoffs in different environments and product values. Even within the ANIMA ACP applicability, there is a significant difference between supply chain logistics for $100 CPE devices and $100,000 core routers.¶
When a registrar receives a pledge voucher-request it in turn submits a registrar voucher-request to the MASA service via an HTTPS interface ([RFC7231]).¶
This is done with an HTTP POST using the operation path value of "/.well-known/est/requestvoucher".¶
The voucher media type "application/voucher-cms+json" is defined in [RFC8366] and is also used for the registrar voucher-request. It is a JSON document that has been signed using a CMS structure. The registrar MUST sign the registrar voucher-request. The entire registrar certificate chain, up to and including the Domain CA, MUST be included in the CMS structure.¶
MASA impementations SHOULD anticipate future media types but of course will simply fail the request if those types are not yet known.¶
The Registrar SHOULD include an [RFC7231] section 5.3.2 "Accept" header field indicating the response media types that are acceptable. This list SHOULD be the entire list presented to the Registrar in the Pledge's original request (see Section 5.2) but MAY be a subset. MASA's are expected to be flexible in what they accept.¶
The registrar populates the voucher-request fields as follows:¶
A nonceless registrar voucher-request MAY be submitted to the MASA. Doing so allows the registrar to request a voucher when the pledge is offline, or when the registrar anticipates not being able to connect to the MASA while the pledge is being deployed. Some use cases require the registrar to learn the appropriate IDevID SerialNumber field and appropriate 'Accept header field' values from the physical device labeling or from the sales channel (out-of-scope for this document).¶
All other fields MAY be omitted in the registrar voucher-request.¶
The "proximity-registrar-cert" field MUST NOT be present in the registrar voucher-request.¶
Example JSON payloads of registrar voucher-requests are in Section 3.3 Examples 2 through 4.¶
The MASA verifies that the registrar voucher-request is internally consistent but does not necessarily authenticate the registrar certificate since the registrar MAY be unknown to the MASA in advance. The MASA performs the actions and validation checks described in the following sub-sections before issuing a voucher.¶
As described in [RFC8366] vouchers are normally short lived to avoid revocation issues. If the request is for a previous (expired) voucher using the same registrar (that is, a Registrar with the same Domain CA) then the request for a renewed voucher SHOULD be automatically authorized. The MASA has sufficient information to determine this by examining the request, the registrar authentication, and the existing audit-log. The issuance of a renewed voucher is logged as detailed in Section 5.6.¶
To inform the MASA that existing vouchers are not to be renewed one can update or revoke the registrar credentials used to authorize the request (see Section 5.5.4 and Section 5.5.3). More flexible methods will likely involve sales channel integration and authorizations (details are out-of-scope of this document).¶
The registrar's certificate chain is extracted from the signature method. The entire registrar certificate chain was included in the CMS structure, as specified in Section 5.5. This CA certificate will be used to populate the "pinned-domain-cert" of the voucher being issued.¶
If this domain CA is unknown to the MASA, then it is to be considered a temporary trust anchor for the rest of the steps in this section. The intention is not to authenticate the message as having come from a fully validated origin, but to establish the consistency of the domain PKI.¶
As described in Section 5.5.2, the MASA has extracted Registrar's domain CA. This is used to validate the CMS signature ([RFC5652]) on the voucher-request.¶
Normal PKIX revocation checking is assumed during voucher-request signature validation. This CA certificate MAY have Certificate Revocation List distribution points, or Online Certificate Status Protocol (OCSP) information ([RFC6960]). If they are present, the MASA MUST be able to reach the relevant servers belonging to the Registrar's domain CA to perform the revocation checks.¶
The use of OCSP Stapling is preferred.¶
The MASA MUST verify that the registrar voucher-request is signed by a registrar. This is confirmed by verifying that the id-kp-cmcRA extended key usage extension field (as detailed in EST RFC7030 section 3.6.1) exists in the certificate of the entity that signed the registrar voucher-request. This verification is only a consistency check that the unauthenticated domain CA intended the voucher-request signer to be a registrar. Performing this check provides value to the domain PKI by assuring the domain administrator that the MASA service will only respect claims from authorized Registration Authorities of the domain.¶
Even when a domain CA is authenticated to the MASA, and there is strong sales channel integration to understand who the legitimate owner is, the above cmcRC check prevents arbitrary End-Entity certificates (such as an LDevID certificate) from having vouchers issued against them.¶
Other cases of inappropriate voucher issuance are detected by examination of the audit log.¶
If a nonceless voucher-request is submitted the MASA MUST authenticate the registrar as described in either EST [RFC7030] section 3.2.3, section 3.3.2, or by validating the registrar's certificate used to sign the registrar voucher-request using a configured trust anchor. Any of these methods reduce the risk of DDoS attacks and provide an authenticated identity as an input to sales channel integration and authorizations (details are out-of-scope of this document).¶
In the nonced case, validation of the Registrar's identity (via TLS Client Certificate or HTTP authentication) MAY be omitted if the device policy is to accept audit-only vouchers.¶
The MASA MAY verify that the registrar voucher-request includes the 'prior-signed-voucher-request' field. If so the prior-signed-voucher-request MUST include a 'proximity-registrar-cert' that is consistent with the certificate used to sign the registrar voucher-request. Additionally the voucher-request serial-number leaf MUST match the pledge serial-number that the MASA extracts from the signing certificate of the prior-signed-voucher-request. The consistency check described above is checking that the 'proximity-registrar-cert' SPKI fingerprint exists within the registrar voucher-request CMS signature's certificate chain. This is substantially the same as the pin validation described in in [RFC7469] section 2.6, paragraph three.¶
If these checks succeed the MASA updates the voucher and audit-log assertion leafs with the "proximity" assertion, as defined by [RFC8366] section 5.3.¶
The MASA does not verify the nonce itself. If the registrar voucher-request contains a nonce, and the prior-signed-voucher-request exists, then the MASA MUST verify that the nonce is consistent. (Recall from above that the voucher-request might not contain a nonce, see Section 5.5 and Section 5.5.4).¶
The MASA populates the audit-log with the nonce that was verified. If a nonceless voucher is issued, then the audit-log is to be populated with the JSON value "null".¶
The MASA voucher response to the registrar is forwarded without changes to the pledge; therefore this section applies to both the MASA and the registrar. The HTTP signaling described applies to both the MASA and registrar responses.¶
When a voucher request arrives at the registrar, if it has a cached response from the MASA for the corresponding registrar voucher-request, that cached response can be used according to local policy; otherwise the registrar constructs a new registrar voucher-request and sends it to the MASA.¶
Registrar evaluation of the voucher itself is purely for transparency and audit purposes to further inform log verification (see Section 5.8.3) and therefore a registrar could accept future voucher formats that are opaque to the registrar.¶
If the voucher-request is successful, the server (MASA responding to registrar or registrar responding to pledge) response MUST contain an HTTP 200 response code. The server MUST answer with a suitable 4xx or 5xx HTTP [RFC7230] error code when a problem occurs. In this case, the response data from the MASA MUST be a plaintext human-readable (UTF-8) error message containing explanatory information describing why the request was rejected.¶
The registrar MAY respond with an HTTP 202 ("the request has been accepted for processing, but the processing has not been completed") as described in EST [RFC7030] section 4.2.3 wherein the client "MUST wait at least the specified 'Retry-After' time before repeating the same request". (see [RFC7231] section 6.6.4) The pledge is RECOMMENDED to provide local feedback (blinked LED etc) during this wait cycle if mechanisms for this are available. To prevent an attacker registrar from significantly delaying bootstrapping the pledge MUST limit the 'Retry-After' time to 60 seconds. Ideally the pledge would keep track of the appropriate Retry-After header field values for any number of outstanding registrars but this would involve a state table on the pledge. Instead the pledge MAY ignore the exact Retry-After value in favor of a single hard coded value (a registrar that is unable to complete the transaction after the first 60 seconds has another chance a minute later). A pledge SHOULD only maintain a 202 retry-state for up to 4 days, which is longer than a long weekend, after which time the enrollment attempt fails and the pledge returns to discovery state.¶
A pledge that retries a request after receiving a 202 message MUST resend the same voucher-request. It MUST NOT sign a new voucher-request each time, and in particular, it MUST NOT change the nonce value.¶
In order to avoid infinite redirect loops, which a malicious registrar might do in order to keep the pledge from discovering the correct registrar, the pledge MUST NOT follow more than one redirection (3xx code) to another web origins. EST supports redirection but requires user input; this change allows the pledge to follow a single redirection without a user interaction.¶
A 403 (Forbidden) response is appropriate if the voucher-request is not signed correctly, stale, or if the pledge has another outstanding voucher that cannot be overridden.¶
A 404 (Not Found) response is appropriate when the request is for a device that is not known to the MASA.¶
A 406 (Not Acceptable) response is appropriate if a voucher of the desired type or using the desired algorithms (as indicated by the Accept: header fields, and algorithms used in the signature) cannot be issued such as because the MASA knows the pledge cannot process that type. The registrar SHOULD use this response if it determines the pledge is unacceptable due to inventory control, MASA audit-logs, or any other reason.¶
A 415 (Unsupported Media Type) response is appropriate for a request that has a voucher-request or Accept: value that is not understood.¶
The voucher response format is as indicated in the submitted Accept header fields or based on the MASA's prior understanding of proper format for this Pledge. Only the [RFC8366] "application/voucher-cms+json" media type is defined at this time. The syntactic details of vouchers are described in detail in [RFC8366]. Figure 14 shows a sample of the contents of a voucher.¶
The MASA populates the voucher fields as follows:¶
Whenever a voucher is issued the MASA MUST update the audit-log sufficiently to generate the response as described in Section 5.8.1. The internal state requirements to maintain the audit-log are out-of-scope.¶
The pledge MUST verify the voucher signature using the manufacturer-installed trust anchor(s) associated with the manufacturer's MASA (this is likely included in the pledge's firmware). Management of the manufacturer-installed trust anchor(s) is out-of-scope of this document; this protocol does not update these trust anchor(s).¶
The pledge MUST verify the serial-number field of the signed voucher matches the pledge's own serial-number.¶
The pledge MUST verify the nonce information in the voucher. If present, the nonce in the voucher must match the nonce the pledge submitted to the registrar; vouchers with no nonce can also be accepted (according to local policy, see Section 7.2.¶
The pledge MUST be prepared to parse and fail gracefully from a voucher response that does not contain a 'pinned-domain-cert' field. Such a thing indicates a failure to enroll in this domain, and the pledge MUST attempt joining with other available Join Proxy.¶
The pledge MUST be prepared to ignore additional fields that it does not recognize.¶
The 'pinned-domain-cert' element of the voucher contains the domain CA's public key. The pledge MUST use the 'pinned-domain-cert' trust anchor to immediately complete authentication of the provisional TLS connection.¶
If a registrar's credentials cannot be verified using the pinned-domain-cert trust anchor from the voucher then the TLS connection is immediately discarded and the pledge abandons attempts to bootstrap with this discovered registrar. The pledge SHOULD send voucher status telemetry (described below) before closing the TLS connection. The pledge MUST attempt to enroll using any other proxies it has found. It SHOULD return to the same proxy again after unsuccessful attempts with other proxies. Attempts should be made repeated at intervals according to the backoff timer described earlier. Attempts SHOULD be repeated as failure may be the result of a temporary inconsistency (an inconsistently rolled registrar key, or some other mis-configuration). The inconsistency could also be the result an active MITM attack on the EST connection.¶
The registrar MUST use a certificate that chains to the pinned-domain-cert as its TLS server certificate.¶
The pledge's PKIX path validation of a registrar certificate's validity period information is as described in Section 2.6.1. Once the PKIX path validation is successful the TLS connection is no longer provisional.¶
The pinned-domain-cert MAY be installed as an trust anchor for future operations such as enrollment (e.g. [RFC7030] as recommended) or trust anchor management or raw protocols that do not need full PKI based key management. It can be used to authenticate any dynamically discovered EST server that contain the id-kp-cmcRA extended key usage extension as detailed in EST RFC7030 section 3.6.1; but to reduce system complexity the pledge SHOULD avoid additional discovery operations. Instead the pledge SHOULD communicate directly with the registrar as the EST server. The 'pinned-domain-cert' is not a complete distribution of the [RFC7030] section 4.1.3 CA Certificate Response, which is an additional justification for the recommendation to proceed with EST key management operations. Once a full CA Certificate Response is obtained it is more authoritative for the domain than the limited 'pinned-domain-cert' response.¶
The domain is expected to provide indications to the system administrators concerning device lifecycle status. To facilitate this it needs telemetry information concerning the device's status.¶
To indicate pledge status regarding the voucher, the pledge MUST post a status message to the Registrar.¶
The posted data media type: application/json¶
The client sends an HTTP POST to the server at the URI ".well-known/est/voucher_status".¶
The format and semantics described below are for version 1. A version field is included to permit significant changes to this feedback in the future. A Registrar that receives a status message with a version larger than it knows about SHOULD log the contents and alert a human.¶
The Status field indicates if the voucher was acceptable. Boolean values are acceptable, where "true" indicates the voucher was acceptable.¶
If the voucher was not acceptable the Reason string indicates why. In the failure case this message may be sent to an unauthenticated, potentially malicious registrar and therefore the Reason string SHOULD NOT provide information beneficial to an attacker. The operational benefit of this telemetry information is balanced against the operational costs of not recording that an voucher was ignored by a client the registrar expected to continue joining the domain.¶
The reason-context attribute is an arbitrary JSON object (literal value or hash of values) which provides additional information specific to this pledge. The contents of this field are not subject to standardization.¶
The version and status fields MUST be present. The Reason field SHOULD be present whenever the status field is false. The Reason-Context field is optional.¶
The keys to this JSON object are case-sensitive and MUST be lowercase. Figure 15 shows an example JSON.¶
The server SHOULD respond with an HTTP 200 but MAY simply fail with an HTTP 404 error. The client ignores any response. Within the server logs the server SHOULD capture this telemetry information.¶
Additional standard JSON fields in this POST MAY be added, see Section 8.5. A server that sees unknown fields should log them, but otherwise ignore them.¶
After receiving the pledge status telemetry Section 5.7, the registrar SHOULD request the MASA audit-log from the MASA service.¶
This is done with an HTTP POST using the operation path value of "/.well-known/est/requestauditlog".¶
The registrar SHOULD HTTP POST the same registrar voucher-request as it did when requesting a voucher (using the same Content-Type). It is posted to the /requestauditlog URI instead. The "idevid-issuer" and "serial-number" informs the MASA which log is requested so the appropriate log can be prepared for the response. Using the same media type and message minimizes cryptographic and message operations although it results in additional network traffic. The relying MASA implementation MAY leverage internal state to associate this request with the original, and by now already validated, voucher-request so as to avoid an extra crypto validation.¶
A registrar MAY request logs at future times. If the registrar generates a new request then the MASA is forced to perform the additional cryptographic operations to verify the new request.¶
A MASA that receives a request for a device that does not exist, or for which the requesting owner was never an owner returns an HTTP 404 ("Not found") code.¶
It is reasonable for a Registrar, that the MASA does not believe to be the current owner, to request the audit-log. There are probably reasons for this which are hard to predict in advance. For instance, such a registrar may not be aware that the device has been resold; it may be that the device has been resold inappropriately, and this is how the original owner will learn of the occurance. It is also possible that the device legitimately spends time in two different networks.¶
Rather than returning the audit-log as a response to the POST (with a return code 200), the MASA MAY instead return a 201 ("Created") response ([RFC7231] sections 6.3.2 and 7.1), with the URL to the prepared (and idempotent, therefore cachable) audit response in the Location: header field.¶
In order to avoid enumeration of device audit-logs, MASA that return URLs SHOULD take care to make the returned URL unguessable. [W3C.WD-capability-urls-20140218] provides very good additional guidance. For instance, rather than returning URLs containing a database number such as https://example.com/auditlog/1234 or the EUI of the device such https://example.com/auditlog/10-00-00-11-22-33, the MASA SHOULD return a randomly generated value (a "slug" in web parlance). The value is used to find the relevant database entry.¶
A MASA that returns a code 200 MAY also include a Location: header for future reference by the registrar.¶
A log data file is returned consisting of all log entries associated with the device selected by the IDevID presented in the request. The audit log may be abridged by removal of old or repeated values as explained below. The returned data is in JSON format ([RFC8259]), and the Content-Type SHOULD be "application/json".¶
The following CDDL ([RFC8610]) explains the structure of the JSON format audit-log response:¶
An example:¶
The domainID is a binary SubjectKeyIdentifier value calculated according to Section 5.8.2. It is encoded once in base64 in order to be transported in this JSON container.¶
The date is in [RFC3339] format, which is consistent with typical JavaScript usage of JSON.¶
The truncation structure MAY be omitted if all values are zero. Any counter missing from the truncation structure is the be assumed to be zero.¶
The nonce is a string, as provided in the voucher-request, and used in the voucher. If no nonce was placed in the resulting voucher, then a value of null SHOULD be used in preference to omitting the entry. While the nonce is often created as a base64 encoded random series of bytes, this should not be assumed.¶
Distribution of a large log is less than ideal. This structure can be optimized as follows: Nonced or Nonceless entries for the same domainID MAY be abridged from the log leaving only the single most recent nonced or nonceless entry for that domainID. In the case of truncation the 'event' truncation value SHOULD contain a count of the number of events for this domainID that were omitted. The log SHOULD NOT be further reduced but there could exist operational situation where maintaining the full log is not possible. In such situations the log MAY be arbitrarily abridged for length, with the number of removed entries indicated as 'arbitrary'.¶
If the truncation count exceeds 1024 then the MASA MAY use this value without further incrementing it.¶
A log where duplicate entries for the same domain have been omitted ("nonced duplicates" and/or "nonceless duplicates) could still be acceptable for informed decisions. A log that has had "arbitrary" truncations is less acceptable but manufacturer transparency is better than hidden truncations.¶
A registrar that sees a version value greater than 1 indicates an audit log format that has been enhanced with additional information. No information will be removed in future versions; should an incompatible change be desired in the future, then a new HTTP end point will be used.¶
This document specifies a simple log format as provided by the MASA service to the registrar. This format could be improved by distributed consensus technologies that integrate vouchers with technologies such as block-chain or hash trees or optimized logging approaches. Doing so is out of the scope of this document but is an anticipated improvement for future work. As such, the registrar SHOULD anticipate new kinds of responses, and SHOULD provide operator controls to indicate how to process unknown responses.¶
The domainID is a binary value (a BIT STRING) that uniquely identifies a Registrar by the "pinned-domain-cert"¶
If the "pinned-domain-cert" certificate includes the SubjectKeyIdentifier (Section 4.2.1.2 [RFC5280]), then it is to be used as the domainID. If not, the SPKI Fingerprint as described in [RFC7469] section 2.4 is to be used. This value needs to be calculated by both MASA (to populate the audit-log), and by the Registrar (to recognize itself in the audit log).¶
[RFC5280] section 4.2.1.2 does not mandate that the SubjectKeyIdentifier extension be present in non-CA certificates. It is RECOMMENDED that Registrar certificates (even if self-signed), always include the SubjectKeyIdentifier to be used as a domainID.¶
The domainID is determined from the certificate chain associated with the pinned-domain-cert and is used to update the audit-log.¶
Each time the Manufacturer Authorized Signing Authority (MASA) issues a voucher, it appends details of the assignment to an internal audit log for that device. The internal audit log is processed when responding to requests for details as described in Section 5.8. The contents of the audit log can express a variety of trust levels, and this section explains what kind of trust a registrar can derive from the entries.¶
While the audit log provides a list of vouchers that were issued by the MASA, the vouchers are issued in response to voucher-requests, and it is the contents of the voucher-requests which determines how meaningful the audit log entries are.¶
A registrar SHOULD use the log information to make an informed decision regarding the continued bootstrapping of the pledge. The exact policy is out of scope of this document as it depends on the security requirements within the registrar domain. Equipment that is purchased pre-owned can be expected to have an extensive history. The following discussion is provided to help explain the value of each log element:¶
A relatively simple policy is to white list known (internal or external) domainIDs, and require all vouchers to have a nonce. An alternative is to require that all nonceless vouchers be from a subset (e.g. only internal) of domainIDs. If the policy is violated a simple action is to revoke any locally issued credentials for the pledge in question or to refuse to forward the voucher. The Registrar MUST then refuse any EST actions, and SHOULD inform a human via a log. A registrar MAY be configured to ignore (i.e. override the above policy) the history of the device but it is RECOMMENDED that this only be configured if hardware assisted (i.e. TPM anchored) Network Endpoint Assessment (NEA) [RFC5209] is supported.¶
The pledge SHOULD follow the BRSKI operations with EST enrollment operations including "CA Certificates Request", "CSR Attributes" and "Client Certificate Request" or "Server-Side Key Generation", etc. This is a relatively seamless integration since BRSKI API calls provide an automated alternative to the manual bootstrapping method described in [RFC7030]. As noted above, use of HTTP persistent connections simplifies the pledge state machine.¶
Although EST allows clients to obtain multiple certificates by sending multiple Certificate Signing Requests (CSR) requests, BRSKI does not support this mechanism directly. This is because BRSKI pledges MUST use the CSR Attributes request ([RFC7030] section 4.5). The registrar MUST validate the CSR against the expected attributes. This implies that client requests will "look the same" and therefore result in a single logical certificate being issued even if the client were to make multiple requests. Registrars MAY contain more complex logic but doing so is out-of-scope of this specification. BRSKI does not signal any enhancement or restriction to this capability.¶
The pledge SHOULD request the full EST Distribution of CA Certificates message. See RFC7030, section 4.1.¶
This ensures that the pledge has the complete set of current CA certificates beyond the pinned-domain-cert (see Section 5.6.2 for a discussion of the limitations inherent in having a single certificate instead of a full CA Certificates response.) Although these limitations are acceptable during initial bootstrapping, they are not appropriate for ongoing PKIX end entity certificate validation.¶
Automated bootstrapping occurs without local administrative configuration of the pledge. In some deployments it is plausible that the pledge generates a certificate request containing only identity information known to the pledge (essentially the X.509 IDevID information) and ultimately receives a certificate containing domain specific identity information. Conceptually the CA has complete control over all fields issued in the end entity certificate. Realistically this is operationally difficult with the current status of PKI certificate authority deployments, where the CSR is submitted to the CA via a number of non-standard protocols. Even with all standardized protocols used, it could operationally be problematic to expect that service specific certificate fields can be created by a CA that is likely operated by a group that has no insight into different network services/protocols used. For example, the CA could even be outsourced.¶
To alleviate these operational difficulties, the pledge MUST request the EST "CSR Attributes" from the EST server and the EST server needs to be able to reply with the attributes necessary for use of the certificate in its intended protocols/services. This approach allows for minimal CA integrations and instead the local infrastructure (EST server) informs the pledge of the proper fields to include in the generated CSR (such as rfc822Name). This approach is beneficial to automated bootstrapping in the widest number of environments.¶
In networks using the BRSKI enrolled certificate to authenticate the ACP (Autonomic Control Plane), the EST CSR attributes MUST include the ACP Domain Information Fields defined in [I-D.ietf-anima-autonomic-control-plane] section 6.1.1.¶
The registrar MUST also confirm that the resulting CSR is formatted as indicated before forwarding the request to a CA. If the registrar is communicating with the CA using a protocol such as full CMC, which provides mechanisms to override the CSR attributes, then these mechanisms MAY be used even if the client ignores CSR Attribute guidance.¶
The pledge MUST request a new client certificate. See RFC7030, section 4.2.¶
For automated bootstrapping of devices, the administrative elements providing bootstrapping also provide indications to the system administrators concerning device lifecycle status. This might include information concerning attempted bootstrapping messages seen by the client. The MASA provides logs and status of credential enrollment. [RFC7030] assumes an end user and therefore does not include a final success indication back to the server. This is insufficient for automated use cases.¶
In order to communicate this indicator, the client HTTP POSTs a JSON dictionary with a number of attributes described below to the new EST endpoint at "/.well-known/est/enrollstatus".¶
When indicating a successful enrollment the client SHOULD first re-establish the EST TLS session using the newly obtained credentials. TLS 1.2 supports doing this in-band, but TLS 1.3 does not. The client SHOULD therefore always close the existing TLS connection, and start a new one.¶
In the case of a failed enrollment, the client MUST send the telemetry information over the same TLS connection that was used for the enrollment attempt, with a Reason string indicating why the most recent enrollment failed. (For failed attempts, the TLS connection is the most reliable way to correlate server-side information with what the client provides.)¶
The reason-context attribute is an arbitrary JSON object (literal value or hash of values) which provides additional information specific to the failure to unroll from this pledge. The contents of this field are not subject to standardization. This is represented by the group-socket "$$arbitrary-map" in the CDDL.¶
In the case of a SUCCESS the Reason string is omitted.¶
An example status report can be seen below. It is sent with with the media type: application/json¶
The server SHOULD respond with an HTTP 200 but MAY simply fail with an HTTP 404 error.¶
Within the server logs the server MUST capture if this message was received over an TLS session with a matching client certificate.¶
Pledges that require multiple certificates could establish direct EST connections to the registrar.¶
This document describes extensions to EST for the purposes of bootstrapping of remote key infrastructures. Bootstrapping is relevant for CoAP enrollment discussions as well. The definition of EST and BRSKI over CoAP is not discussed within this document beyond ensuring proxy support for CoAP operations. Instead it is anticipated that a definition of CoAP mappings will occur in subsequent documents such as [I-D.ietf-ace-coap-est] and that CoAP mappings for BRSKI will be discussed either there or in future work.¶
[RFC7030] defines its endpoints to include a "Content-Transfer-Encoding" heading, and the payloads to be [RFC4648] Base64 encoded DER.¶
When used within BRSKI, the original RFC7030 EST endpoints remain Base64 encoded, but the new BRSKI end points which send and receive binary artifacts (specifically, "/.well-known/est/requestvoucher") are binary. That is, no encoding is used.¶
In the BRSKI context, the EST "Content-Transfer-Encoding" header field if present, SHOULD be ignored. This header field does not need to be included.¶
A common requirement of bootstrapping is to support less secure operational modes for support specific use cases. This section suggests a range of mechanisms that would alter the security assurance of BRSKI to accommodate alternative deployment architectures and mitigate lifecycle management issues identified in Section 10. They are presented here as informative (non-normative) design guidance for future standardization activities. Section 9 provides standardization applicability statements for the ANIMA ACP. Other users would be expected that subsets of these mechanisms could be profiled with an accompanying applicability statements similar to the one described in Section 9.¶
This section is considered non-normative in the generality of the protocol. Use of the suggested mechanisms here MUST be detailed in specific profiles of BRSKI, such as in Section 9.¶
This section explains the trust relationships detailed in Section 2.4:¶
+--------+ +---------+ +------------+ +------------+ | Pledge | | Join | | Domain | |Manufacturer| | | | Proxy | | Registrar | | Service | | | | | | | | (Internet) | +--------+ +---------+ +------------+ +------------+¶
Figure 10¶
The following is a list of alternative behaviours that the pledge can be programmed to implement. These behaviours are not mutually exclusive, nor are they dependent upon each other. Some of these methods enable offline and emergency (touch based) deployment use cases. Normative language is used as these behaviours are referenced in later sections in a normative fashion.¶
It is RECOMMENDED that "trust on first use" or any method of skipping voucher validation (including use of craft serial console) only be available if hardware assisted Network Endpoint Assessment (NEA: [RFC5209]) is supported. This recommendation ensures that domain network monitoring can detect inappropriate use of offline or emergency deployment procedures when voucher-based bootstrapping is not used.¶
A registrar can choose to accept devices using less secure methods. They MUST NOT be the default behavior. These methods may be acceptable in situations where threat models indicate that low security is adequate. This includes situations where security decisions are being made by the local administrator:¶
Lower security modes chosen by the MASA service affect all device deployments unless the lower-security behavior is tied to specific device identities. The modes described below can be applied to specific devices via knowledge of what devices were sold. They can also be bound to specific customers (independent of the device identity) by authenticating the customer's Registrar.¶
A MASA has the option of not including a nonce in the voucher, and/or not requiring one to be present in the voucher-request. This results in distribution of a voucher that may never expire and in effect makes the specified Domain an always trusted entity to the pledge during any subsequent bootstrapping attempts. That a nonceless voucher was issued is captured in the log information so that the registrar can make appropriate security decisions when a pledge joins the Domain. Nonceless vouchers are useful to support use cases where registrars might not be online during actual device deployment.¶
While a nonceless voucher may include an expiry date, a typical use for a nonceless voucher is for it to be long-lived. If the device can be trusted to have an accurate clock (the MASA will know), then a nonceless voucher CAN be issued with a limited lifetime.¶
A more typical case for a nonceless voucher is for use with offline onboarding scenarios where it is not possible to pass a fresh voucher-request to the MASA. The use of a long-lived voucher also eliminates concern about the availability of the MASA many years in the future. Thus many nonceless vouchers will have no expiry dates.¶
Thus, the long lived nonceless voucher does not require the proof that the device is online. Issuing such a thing is only accepted when the registrar is authenticated by the MASA and the MASA is authorized to provide this functionality to this customer. The MASA is RECOMMENDED to use this functionality only in concert with an enhanced level of ownership tracking, the details of which are out of scope for this document.¶
If the pledge device is known to have a real-time-clock that is set from the factory, use of a voucher validity period is RECOMMENDED.¶
A MASA has the option of not verifying ownership before responding with a voucher. This is expected to be a common operational model because doing so relieves the manufacturer providing MASA services from having to track ownership during shipping and supply chain and allows for a very low overhead MASA service. A registrar uses the audit log information as a defense in depth strategy to ensure that this does not occur unexpectedly (for example when purchasing new equipment the registrar would throw an error if any audit log information is reported.) The MASA SHOULD verify the 'prior-signed-voucher-request' information for pledges that support that functionality. This provides a proof-of-proximity check that reduces the need for ownership verification. The proof-of-proximity comes from the assumption that the pledge and Join Proxy are on the same link-local connection.¶
A MASA that practices Trust-on-First-Use (TOFU) for Registrar identity may wish to annotate the origin of the connection by IP address or netblock, and restrict future use of that identity from other locations. A MASA that does this SHOULD take care to not create nuisance situations for itself when a customer has multiple registrars, or uses outgoing IPv4 NAT44 connections that change frequently.¶
This section deals with the problem of a MASA that is no longer available due to a failed business, or the situation where a MASA is uncooperative to a secondary sale.¶
A manufacturer could offer a management mechanism that allows the list of voucher verification trust anchors to be extended. [I-D.ietf-netconf-keystore] is one such interface that could be implemented using YANG. Pretty much any configuration mechanism used today could be extended to provide the needed additional update. A manufacturer could even decide to install the domain CA trust anchors received during the EST "cacerts" step as voucher verification anchors. Some additional signals will be needed to clearly identify which keys have voucher validation authority from among those signed by the domain CA. This is future work.¶
With the above change to the list of anchors, vouchers can be issued by an alternate MASA. This could be the previous owner (the seller), or some other trusted third party who is mediating the sale. If it was a third party, then the seller would need to have taken steps to introduce the third party configuration to the device prior disconnection. The third party (e.g. a wholesaler of used equipment) could however use a mechanism described in Section 7.2 to take control of the device after receiving it physically. This would permit the third party to act as the MASA for future onboarding actions. As the IDevID certificate probably can not be replaced, the new owner's Registrar would have to support an override of the MASA URL.¶
To be useful for resale or other transfers of ownership one of two situations will need to occur. The simplest is that the device is not put through any kind of factory default/reset before going through onboarding again. Some other secure, physical signal would be needed to initiate it. This is most suitable for redeploying a device within the same Enterprise. This would entail having previous configuration in the system until entirely replaced by the new owner, and represents some level of risk.¶
The second mechanism is that there would need to be two levels of factory reset. One would take the system back entirely to manufacturer state, including removing any added trust anchors, and the second (more commonly used) one would just restore the configuration back to a known default without erasing trust anchors. This weaker factory reset might leave valuable credentials on the device and this may be unacceptable to some owners.¶
As a third option, the manufacturer's trust anchors could be entirely overwritten with local trust anchors. A factory default would never restore those anchors. This option comes with a lot of power, but also a lot of responsibility: if access to the private part of the new anchors are lost the manufacturer may be unable to help.¶
This document requires the following IANA actions:¶
This document registers a URI in the "IETF XML Registry" [RFC3688]. IANA is asked to register the following:¶
URI: urn:ietf:params:xml:ns:yang:ietf-voucher-request Registrant Contact: The ANIMA WG of the IETF. XML: N/A, the requested URI is an XML namespace.¶
This document registers a YANG module in the "YANG Module Names" registry [RFC6020]. IANA is asked to register the following:¶
name: ietf-voucher-request namespace: urn:ietf:params:xml:ns:yang:ietf-voucher-request prefix: vch reference: THIS DOCUMENT¶
This document extends the definitions of "est" (so far defined via RFC7030) in the "https://www.iana.org/assignments/well-known-uris/well-known-uris.xhtml" registry. IANA is asked to change the registration of "est" to include RFC7030 and this document.¶
IANA is requested to register the following:¶
This document requests a number for id-mod-MASAURLExtn2016(TBD) from the pkix(7) id-mod(0) Registry.¶
This document has received an early allocation from the id-pe registry (SMI Security for PKIX Certificate Extension) for id-pe-masa-url with the value 32, resulting in an OID of 1.3.6.1.5.5.7.1.32.¶
IANA is requested to create a new Registry entitled: "BRSKI Parameters", and within that Registry to create a table called: "Pledge BRSKI Status Telemetry Attributes". New items can be added using the Specification Required. The following items are to be in the initial registration, with this document (Section 5.7) as the reference:¶
IANA is requested to register the following Service Names:¶
Service Name: brski-proxy Transport Protocol(s): tcp Assignee: IESG <iesg@ietf.org>. Contact: IESG <iesg@ietf.org> Description: The Bootstrapping Remote Secure Key Infrastructures Proxy Reference: [This document] Service Name: brski-registrar Transport Protocol(s): tcp Assignee: IESG <iesg@ietf.org>. Contact: IESG <iesg@ietf.org> Description: The Bootstrapping Remote Secure Key Infrastructures Registrar Reference: [This document]¶
This document provides a solution to the requirements for secure bootstrap set out in Using an Autonomic Control Plane for Stable Connectivity of Network Operations, Administration, and Maintenance [RFC8368], A Reference Model for Autonomic Networking [I-D.ietf-anima-reference-model] and specifically the An Autonomic Control Plane (ACP) [I-D.ietf-anima-autonomic-control-plane], section 3.2 (Secure Bootstrap), and section 6.1 (ACP Domain, Certificate and Network).¶
The protocol described in this document has appeal in a number of other non-ANIMA use cases. Such uses of the protocol will be deploying into other environments with different tradeoffs of privacy, security, reliability and autonomy from manufacturers. As such those use cases will need to provide their own applicability statements, and will need to address unique privacy and security considerations for the environments in which they are used.¶
The autonomic control plane (ACP) that is bootstrapped by the BRSKI protocol is typically used in medium to large Internet Service Provider organizations. Equivalent enterprises that have significant layer-3 router connectivity also will find significant benefit, particularly if the Enterprise has many sites. (A network consisting of primarily layer-2 is not excluded, but the adjacencies that the ACP will create and maintain will not reflect the topology until all devices participate in the ACP).¶
In the ACP, the Join Proxy is found to be proximal because communication between the pledge and the join proxy is exclusively on IPv6 Link-Local addresses. The proximity of the Join Proxy to the Registrar is validated by the Registrar using ANI ACP IPv6 Unique Local Addresses (ULA). ULAs are not routable over the Internet, so as long as the Join Proxy is operating correctly the proximity asssertion is satisfied. Other uses of BRSKI will need make similar analysis if they use proximity assertions.¶
As specified in the ANIMA charter, this work "..focuses on professionally-managed networks." Such a network has an operator and can do things like install, configure and operate the Registrar function. The operator makes purchasing decisions and is aware of what manufacturers it expects to see on its network.¶
Such an operator is also capable of performing bootstrapping of a device using a serial-console (craft console). The zero-touch mechanism presented in this and the ACP document [I-D.ietf-anima-autonomic-control-plane] represents a significiant efficiency: in particular it reduces the need to put senior experts on airplanes to configure devices in person.¶
There is a recognition as the technology evolves that not every situation may work out, and occasionally a human may still have to visit. In recognition of this, some mechanisms are presented in Section 7.2. The manufacturer MUST provide at least one of the one-touch mechanisms described that permit enrollment to be proceed without availability of any manufacturer server (such as the MASA).¶
The BRSKI protocol is going into environments where there have already been quite a number of vendor proprietary management systems. Those are not expected to go away quickly, but rather to leverage the secure credentials that are provisioned by BRSKI. The connectivity requirements of said management systems are provided by the ACP.¶
This section collects operational requirements based upon the three roles involved in BRSKI: The Manufacturer Authorized Signing Authority (MASA), the (Domain) Owner and the Device. It should be recognized that the manufacturer may be involved in two roles, as it creates the software/firmware for the device, and also may be the operator of the MASA.¶
The requirements in this section are presented using BCP14 ([RFC2119], [RFC8174]) language. These do not represent new normative statements, just a review of a few such things in one place by role. They also apply specifically to the ANIMA ACP use case. Other use cases likely have similar, but MAY have different requirements.¶
The manufacturer MUST arrange for an online service to be available called the MASA. It MUST be available at the URL which is encoded in the IDevID certificate extensions described in Section 2.3.2.¶
The online service MUST have access to a private key with which to sign [RFC8366] format voucher artifacts. The public key, certificate, or certificate chain MUST be built in to the device as part of the firmware.¶
It is RECOMMENDED that the manufacturer arrange for this signing key (or keys) to be escrowed according to typical software source code escrow practices [softwareescrow].¶
The MASA accepts voucher requests from Domain Owners according to an operational practice appropriate for the device. This can range from any domain owner (first-come first-served, on a TOFU-like basis), to full sales channel integration where Domain Owners need to be positively identified by TLS Client Certicate pinned, or HTTP Authentication process. The MASA creates signed voucher artifacts according to its internally defined policies.¶
The MASA MUST operate an audit log for devices that is accessible. The audit log is designed to be easily cacheable and the MASA MAY find it useful to put this content on a CDN.¶
The domain owner MUST operate an EST ([RFC7030]) server with the extensions described in this document. This is the JRC or Registrar. This JRC/EST server MUST announce itself using GRASP within the ACP. This EST server will typically reside with the Network Operations Center for the organization.¶
The domain owner MAY operate an internal certificate authority (CA) that is seperate from the EST server, or it MAY combine all activities into a single device. The determination of the architecture depends upon the scale and resiliency requirements of the organization. Multiple JRC instances MAY be announced into the ACP from multiple locations to achieve an appropriate level of redundancy.¶
In order to recognize which devices and which manufacturers are welcome on the domain owner's network, the domain owner SHOULD maintain a white list of manufacturers. This MAY extend to integration with purchasing departments to know the serial numbers of devices.¶
The domain owner SHOULD use the resulting overlay ACP network to manage devices, replacing legacy out-of-band mechanisms.¶
The domain owner SHOULD operate one or more EST servers which can be used to renew the domain certificates (LDevIDs) which are deployed to devices. These servers MAY be the same as the JRC, or MAY be a distinct set of devices, as approriate for resiliency.¶
The organization MUST take appropriate precautions against loss of access to the certificate authority private key. Hardware security modules and/or secret splitting are appropriate.¶
Devices MUST come with built-in trust anchors that permit the device to validate vouchers from the MASA.¶
Device MUST come with (unique, per-device) IDevID certificates that include their serial numbers, and the MASA URL extension.¶
Devices are expected to find Join Proxies using GRASP, and then connect to the JRC using the protocol described in this document.¶
Once a domain owner has been validated with the voucher, devices are expected to enroll into the domain using EST. Devices are then expected to form ACPs using IPsec over IPv6 Link-Local addresses as described in [I-D.ietf-anima-autonomic-control-plane]¶
Once a device has been enrolled it SHOULD listen for the address of the JRC using GRASP, and it SHOULD enable itself as a Join Proxy, and announce itself on all links/interfaces using GRASP DULL.¶
Devices are expected to renew their certificates before they expire.¶
The MASA audit log includes the domainID for each domain a voucher has been issued to. This information is closely related to the actual domain identity. A MASA may need additional defenses against Denial of Service attacks (Section 11.1), and this may involve collecting additional (unspecified here) information. This could provide sufficient information for the MASA service to build a detailed understanding the devices that have been provisioned within a domain.¶
There are a number of design choices that mitigate this risk. The domain can maintain some privacy since it has not necessarily been authenticated and is not authoritatively bound to the supply chain.¶
Additionally the domainID captures only the unauthenticated subject key identifier of the domain. A privacy sensitive domain could theoretically generate a new domainID for each device being deployed. Similarly a privacy sensitive domain would likely purchase devices that support proximity assertions from a manufacturer that does not require sales channel integrations. This would result in a significant level of privacy while maintaining the security characteristics provided by Registrar based audit log inspection.¶
During the provisional phase of the BRSKI-EST connection between the Pledge and the Registrar, each party reveals its certificates to each other. For the Pledge, this includes the serialNumber attribute, the MASA URL, and the identity that signed the IDevID certificate.¶
TLS 1.2 reveals the certificate identities to on-path observers, including the Join Proxy.¶
TLS 1.3 reveals the certificate identities only to the end parties, but as the connection is provisional, an on-path attacker (MTIM) can see the certificates. This includes not just malicious attackers, but also Registrars that are visible to the Pledge, but which are not part of the intended domain.¶
The certificate of the Registrar is rather arbitrary from the point of view of the BRSKI protocol. As no [RFC6125] validations are expected to be done, the contents could be easily pseudonymized. Any device that can see a join proxy would be able to connect to the Registrar and learn the identity of the network in question. Even if the contents of the certificate are pseudonymized, it would be possible to correlate different connections in different locations belong to the same entity. This is unlikely to present a significant privacy concern to ANIMA ACP uses of BRSKI, but may be a concern to other users of BRSKI.¶
The certificate of the Pledge could be revealed by a malicious Join Proxy that performed a MITM attack on the provisional TLS connection. Such an attacker would be able to reveal the identity of the Pledge to third parties if it chose to so.¶
Research into a mechanism to do multi-step, multi-party authenticated key agreement, incorporating some kind of zero-knowledge proof would be valuable. Such a mechanism would ideally avoid disclosing identities until pledge, registrar and MASA agree to the transaction. Such a mechanism would need to discover the location of the MASA without knowing the identity of the pledge, or the identity of the MASA. This part of the problem may be unsolveable.¶
With consumer-oriented devices, the "call-home" mechanism in IoT devices raises significant privacy concerns. See [livingwithIoT] and [IoTstrangeThings] for exemplars. The Autonomic Control Plane (ACP) usage of BRSKI is not targeted at individual usage of IoT devices, but rather at the Enterprise and ISP creation of networks in a zero-touch fashion where the "call-home" represents a different class of privacy and lifecycle management concerns.¶
As the Autonomic Control Plane (ACP) usage of BRSKI is not targeted at individual usage of IoT devices, but rather at the Enterprise and ISP creation of networks in a zero-touch fashion, the "call-home" represents a different kind of concern.¶
It needs to be re-iterated that the BRSKI-MASA mechanism only occurs once during the commissioning of the device. It is well defined, and although encrypted with TLS, it could in theory be made auditable as the contents are well defined. This connection does not occur when the device powers on or is restarted for normal routines. (It is conceivable, but remarkably unusual, that a device could be forced to go through a full factory reset during an exceptional firmware update situation, after which enrollment would have be repeated, and a new connection would occur)¶
The BRSKI call-home mechanism is mediated via the owner's Registrar, and the information that is transmitted is directly auditable by the device owner. This is in stark contrast to many "call-home" protocols where the device autonomously calls home and uses an undocumented protocol.¶
While the contents of the signed part of the pledge voucher request can not be changed, they are not encrypted at the registrar. The ability to audit the messages by the owner of the network is a mechanism to defend against exfiltration of data by a nefarious pledge. Both are, to re-iterate, encrypted by TLS while in transit.¶
The BRSKI-MASA exchange reveals the following information to the manufacturer:¶
Based upon the above information, the manufacturer is able to track a specific device from pseudonymous domain identity to the next pseudonymous domain identity. If there is sales-channel integration, then the identities are not pseudonymous.¶
The manufacturer knows the IP address of the Registrar, but it can not see the IP address of the device itself. The manufacturer can not track the device to a detailed physical or network location, only to the location of the Registrar. That is likely to be at the Enterprise or ISPs headquarters.¶
The above situation is to be distinguished from a residential/individual person who registers a device from a manufacturer. Individuals do not tend to have multiple offices, and their registrar is likely on the same network as the device. A manufacturer that sells switching/routing products to enterprises should hardly be surprised if additional purchases switching/routing products are made. Deviations from a historical trend or an establish baseline would, however, be notable.¶
The situation is not improved by the enterprise/ISP using anonymization services such as ToR [Dingledine2004], as a TLS 1.2 connection will reveal the ClientCertificate used, clearly identifying the enterprise/ISP involved. TLS 1.3 is better in this regard, but an active attacker can still discover the parties involved by performing a Man-In-The-Middle-Attack on the first attempt (breaking/killing it with a TCP RST), and then letting subsequent connection pass through.¶
A manufacturer could attempt to mix the BRSKI-MASA traffic in with general traffic their site by hosting the MASA behind the same (set) of load balancers that the companies normal marketing site is hosted behind. This makes lots of sense from a straight capacity planning point of view as the same set of services (and the same set of Distributed Denial of Service mitigations) may be used. Unfortunately, as the BRSKI-MASA connections include TLS ClientCertificate exchanges, this may easily be observed in TLS 1.2, and a traffic analysis may reveal it even in TLS 1.3. This does not make such a plan irrelevant. There may be other organizational reasons to keep the marketing site (which is often subject to frequent re-designs, outsourcing, etc.) separate from the MASA, which may need to operate reliably for decades.¶
As explained above, the manufacturer receives information each time that a device which is in factory-default mode does a zero-touch bootstrap, and attempts to enroll into a domain owner's registrar.¶
The manufacturer is therefore in a position to decline to issue a voucher if it detects that the new owner is not the same as the previous owner.¶
This section has outlined five situations in which a manufacturer could use the voucher system to enforce what are clearly license terms. A manufacturer that attempted to enforce license terms via vouchers would find it rather ineffective as the terms would only be enforced when the device is enrolled, and this is not (to repeat), a daily or even monthly occurrence.¶
Manufacturers of devices often sell different products into different regional markets. Which product is available in which market can be driven by price differentials, support issues (some markets may require manuals and tech-support to be done in the local language), government export regulation (such as whether strong crypto is permitted to be exported, or permitted to be used in a particular market). When an domain owner obtains a device from a different market (they can be new) and transfers it to a different location, this is called a Grey Market.¶
A manufacturer could decide not to issue a voucher to an enterprise/ISP based upon their location. There are a number of ways which this could be determined: from the geolocation of the registrar, from sales channel knowledge about the customer, and what products are (un-)available in that market. If the device has a GPS the coordinates of the device could even be placed into an extension of the voucher.¶
The above actions are not illegal, and not new. Many manufacturers have shipped crypto-weak (exportable) versions of firmware as the default on equipment for decades. The first task of an enterprise/ISP has always been to login to a manufacturer system, show one's "entitlement" (country information, proof that support payments have been made), and receive either a new updated firmware, or a license key that will activate the correct firmware.¶
BRSKI permits the above process to automated (in an autonomic fashion), and therefore perhaps encourages this kind of differentiation by reducing the cost of doing it.¶
An issue that manufacturers will need to deal with in the above automated process is when a device is shipped to one country with one set of rules (or laws or entitlements), but the domain registry is in another one. Which rules apply is something will have to be worked out: the manufacturer could come to believe they are dealing with Grey market equipment, when it is simply dealing with a global enterprise.¶
The most obvious mitigation is not to buy the product. Pick manufacturers that are up-front about their policies, who do not change them gratuitously.¶
Section 7.4.3 describes some ways in which a manufacturer could provide a mechanism to manage the trust anchors and built-in certificates (IDevID) as an extension. There are a variety of mechanism, and some may take a substantial amount of work to get exactly correct. These mechanisms do not change the flow of the protocol described here, but rather allow the starting trust assumptions to be changed. This is an area for future standardization work.¶
Replacement of the voucher validation anchors (usually pointing to the original manufacturer's MASA) with those of the new owner permits the new owner to issue vouchers to subsequent owners. This would be done by having the selling (old) owner to run a MASA.¶
The BRSKI protocol depends upon a trust anchor on the device and an identity on the device. Management of these entities facilitates a few new operational modes without making any changes to the BRSKI protocol. Those modes include: offline modes where the domain owner operates an internal MASA for all devices, resell modes where the first domain owner becomes the MASA for the next (resold-to) domain owner, and services where an aggregator acquires a large variety of devices, and then acts as a pseudonymized MASA for a variety of devices from a variety of manufacturers.¶
Although replacement of the IDevID is not required for all modes described above, a manufacturers could support such a thing. Some may wish to consider replacement of the IDevID as an indication that the device's warrantee is terminated. For others, the privacy requirements of some deployments might consider this a standard operating practice.¶
As discussed at the end of Section 5.8.1, new work could be done to use a distributed consensus technology for the audit log. This would permit the audit log to continue to be useful, even when there is a chain of MASA due to changes of ownership.¶
A common concern has been that a manufacturer could go out of business, leaving owners of devices unable to get new vouchers for existing products. Said products might have been previously deployed, but need to be re-initialized, they might have been purchased used, or they might have kept in a warehouse as long-term spares.¶
The MASA was named the Manufacturer *Authorized* Signing Authority to emphasize that it need not be the manufacturer itself that performs this. It is anticipated that specialist service providers will come to exist that deal with the creation of vouchers in much the same way that many companies have outsourced email, advertising and janitorial services.¶
Further, it is expected that as part of any service agreement that the manufacturer would arrange to escrow appropriate private keys such that a MASA service could be provided by a third party. This has routinely been done for source code for decades.¶
This document details a protocol for bootstrapping that balances operational concerns against security concerns. As detailed in the introduction, and touched on again in Section 7, the protocol allows for reduced security modes. These attempt to deliver additional control to the local administrator and owner in cases where less security provides operational benefits. This section goes into more detail about a variety of specific considerations.¶
To facilitate logging and administrative oversight, in addition to triggering Registrar verification of MASA logs, the pledge reports on voucher parsing status to the registrar. In the case of a failure, this information is informative to a potentially malicious registrar. This is mandated anyway because of the operational benefits of an informed administrator in cases where the failure is indicative of a problem. The registrar is RECOMMENDED to verify MASA logs if voucher status telemetry is not received.¶
To facilitate truly limited clients EST RFC7030 section 3.3.2 requirements that the client MUST support a client authentication model have been reduced in Section 7 to a statement that the registrar "MAY" choose to accept devices that fail cryptographic authentication. This reflects current (poor) practices in shipping devices without a cryptographic identity that are NOT RECOMMENDED.¶
During the provisional period of the connection the pledge MUST treat all HTTP header and content data as untrusted data. HTTP libraries are regularly exposed to non-secured HTTP traffic: mature libraries should not have any problems.¶
Pledges might chose to engage in protocol operations with multiple discovered registrars in parallel. As noted above they will only do so with distinct nonce values, but the end result could be multiple vouchers issued from the MASA if all registrars attempt to claim the device. This is not a failure and the pledge choses whichever voucher to accept based on internal logic. The registrars verifying log information will see multiple entries and take this into account for their analytics purposes.¶
There are uses cases where the MASA could be unavailable or uncooperative to the Registrar. They include active DoS attacks, planned and unplanned network partitions, changes to MASA policy, or other instances where MASA policy rejects a claim. These introduce an operational risk to the Registrar owner in that MASA behavior might limit the ability to bootstrap a pledge device. For example this might be an issue during disaster recovery. This risk can be mitigated by Registrars that request and maintain long term copies of "nonceless" vouchers. In that way they are guaranteed to be able to bootstrap their devices.¶
The issuance of nonceless vouchers themselves creates a security concern. If the Registrar of a previous domain can intercept protocol communications then it can use a previously issued nonceless voucher to establish management control of a pledge device even after having sold it. This risk is mitigated by recording the issuance of such vouchers in the MASA audit log that is verified by the subsequent Registrar and by Pledges only bootstrapping when in a factory default state. This reflects a balance between enabling MASA independence during future bootstrapping and the security of bootstrapping itself. Registrar control over requesting and auditing nonceless vouchers allows device owners to choose an appropriate balance.¶
The MASA is exposed to DoS attacks wherein attackers claim an unbounded number of devices. Ensuring a registrar is representative of a valid manufacturer customer, even without validating ownership of specific pledge devices, helps to mitigate this. Pledge signatures on the pledge voucher-request, as forwarded by the registrar in the prior-signed-voucher-request field of the registrar voucher-request, significantly reduce this risk by ensuring the MASA can confirm proximity between the pledge and the registrar making the request. Supply chain integration ("know your customer") is an additional step that MASA providers and device vendors can explore.¶
The domainID is used as the reference in the audit log to the domain. The domainID is expected to be calculated by a hash that is resistant to a second-preimage attack. Such an attack would allow a second registrar to create audit log entries that are fake.¶
The nonce used by the Pledge in the voucher-request SHOULD be generated by a Strong Cryptographic Sequence ([RFC4086] section 6.2). TLS has a similar requirement.¶
In particular implementations should pay attention to the advance in [RFC4086] section 3, particularly section 3.4. The random seed used by a device at boot MUST be unique across all devices and all bootstraps. Resetting a device to factory default state does not obviate this requirement.¶
A concern has been raised that the pledge voucher-request should contain some content (a nonce) provided by the registrar and/or MASA in order for those actors to verify that the pledge voucher-request is fresh.¶
There are a number of operational problems with getting a nonce from the MASA to the pledge. It is somewhat easier to collect a random value from the registrar, but as the registrar is not yet vouched for, such a registrar nonce has little value. There are privacy and logistical challenges to addressing these operational issues, so if such a thing were to be considered, it would have to provide some clear value. This section examines the impacts of not having a fresh pledge voucher-request.¶
Because the registrar authenticates the pledge, a full Man-in-the-Middle attack is not possible, despite the provisional TLS authentication by the pledge (see Section 5.) Instead we examine the case of a fake registrar (Rm) that communicates with the pledge in parallel or in close time proximity with the intended registrar. (This scenario is intentionally supported as described in Section 4.1.)¶
The fake registrar (Rm) can obtain a voucher signed by the MASA either directly or through arbitrary intermediaries. Assuming that the MASA accepts the registrar voucher-request (either because Rm is collaborating with a legitimate registrar according to supply chain information, or because the MASA is in audit-log only mode), then a voucher linking the pledge to the registrar Rm is issued.¶
Such a voucher, when passed back to the pledge, would link the pledge to registrar Rm, and would permit the pledge to end the provisional state. It now trusts Rm and, if it has any security vulnerabilities leveragable by an Rm with full administrative control, can be assumed to be a threat against the intended registrar.¶
This flow is mitigated by the intended registrar verifying the audit logs available from the MASA as described in Section 5.8. Rm might chose to collect a voucher-request but wait until after the intended registrar completes the authorization process before submitting it. This pledge voucher-request would be 'stale' in that it has a nonce that no longer matches the internal state of the pledge. In order to successfully use any resulting voucher the Rm would need to remove the stale nonce or anticipate the pledge's future nonce state. Reducing the possibility of this is why the pledge is mandated to generate a strong random or pseudo-random number nonce.¶
Additionally, in order to successfully use the resulting voucher the Rm would have to attack the pledge and return it to a bootstrapping enabled state. This would require wiping the pledge of current configuration and triggering a re-bootstrapping of the pledge. This is no more likely than simply taking control of the pledge directly but if this is a consideration the target network is RECOMMENDED to take the following steps:¶
The BRSKI extensions to EST permit a new pledge to be completely configured with domain specific trust anchors. The link from built-in manufacturer-provided trust anchors to domain-specific trust anchors is mediated by the signed voucher artifact.¶
If the manufacturer's IDevID signing key is not properly validated, then there is a risk that the network will accept a pledge that should not be a member of the network. As the address of the manufacturer's MASA is provided in the IDevID using the extension from Section 2.3, the malicious pledge will have no problem collaborating with it's MASA to produce a completely valid voucher.¶
BRSKI does not, however, fundamentally change the trust model from domain owner to manufacturer. Assuming that the pledge used its IDevID with RFC7030 EST and BRSKI, the domain (registrar) still needs to trust the manufacturer.¶
Establishing this trust between domain and manufacturer is outside the scope of BRSKI. There are a number of mechanisms that can adopted including:¶
The existing WebPKI provides a reasonable anchor between manufacturer name and public key. It authenticates the key. It does not provide a reasonable authorization for the manufacturer, so it is not directly useable on it's own.¶
BRSKI depends upon the manufacturer building in trust anchors to the pledge device. The voucher artifact which is signed by the MASA will be validated by the pledge using that anchor. This implies that the manufacturer needs to maintain access to a signing key that the pledge can validate.¶
The manufacturer will need to maintain the ability to make signatures that can be validated for the lifetime that the device could be onboarded. Whether this onboarding lifetime is less than the device lifetime depends upon how the device is used. An inventory of devices kept in a warehouse as spares might not be onboarded for many decades.¶
There are good cryptographic hygiene reasons why a manufacturer would not want to maintain access to a private key for many decades. A manufacturer in that situation can leverage a long-term certificate authority anchor, built-in to the pledge, and then a certificate chain may be incorporated using the normal CMS certificate set. This may increase the size of the voucher artifacts, but that is not a significant issues in non-constrained environments.¶
There are a few other operational variations that manufacturers could consider. For instance, there is no reason that every device need have the same set of trust anchors pre-installed. Devices built in different factories, or on different days, or any other consideration could have different trust anchors built in, and the record of which batch the device is in would be recorded in the asset database. The manufacturer would then know which anchor to sign an artifact against.¶
Aside from the concern about long-term access to private keys, a major limiting factor for the shelf-life of many devices will be the age of the cryptographic algorithms included. A device produced in 2019 will have hardware and software capable of validating algorithms common in 2019, and will have no defense against attacks (both quantum and von-neuman brute force attacks) which have not yet been invented. This concern is orthogonal to the concern about access to private keys, but this concern likely dominates and limits the lifespan of a device in a warehouse. If any update to firmware to support new cryptographic mechanism were possible (while the device was in a warehouse), updates to trust anchors would also be done at the same time.¶
The set of standard operating procedures for maintaining high value private keys is well documented. For instance, the WebPKI provides a number of options for audits at [cabforumaudit], and the DNSSEC root operations are well documented at [dnssecroot].¶
It is not clear if Manufacturers will take this level of precaution, or how strong the economic incentives are to maintain an appropriate level of security.¶
This next section examines the risk due to a compromised manufacturer IDevID signing key. This is followed by examination of the risk due to a compromised MASA key. The third section sections below examines the situation where MASA web server itself is under attacker control, but that the MASA signing key itself is safe in a not-directly connected hardware module.¶
An attacker that has access to the key that the manufacturer uses to sign IDevID certificates can create counterfeit devices. Such devices can claim to be from a particular manufacturer, but be entirely different devices: Trojan horses in effect.¶
As the attacker controls the MASA URL in the certificate, the registrar can be convinced to talk to the attackers' MASA. The Registrar does not need to be in any kind of promiscuous mode to be vulnerable.¶
In addition to creating fake devices, the attacker may also be able to issue revocations for existing certificates if the IDevID certificate process relies upon CRL lists that are distributed.¶
There does not otherwise seem to be any risk from this compromise to devices which are already deployed, or which are sitting locally in boxes waiting for deployment (local spares). The issue is that operators will be unable to trust devices which have been in an uncontrolled warehouse as they do not know if those are real devices.¶
There are two periods of time in which to consider: when the MASA key has fallen into the hands of an attacker, and after the MASA recognizes that the key has been compromised.¶
An attacker that has access to the MASA signing key could create vouchers. These vouchers could be for existing deployed devices, or for devices which are still in a warehouse. In order to exploit these vouchers two things need to occur: the device has to go through a factory default boot cycle, and the registrar has to be convinced to contact the attacker's MASA.¶
If the attacker controls a Registrar which is visible to the device, then there is no difficulty in delivery of the false voucher. A possible practical example of an attack like this would be in a data center, at an ISP peering point (whether a public IX, or a private peering point). In such a situation, there are already cables attached to the equipment that lead to other devices (the peers at the IX), and through those links, the false voucher could be delivered. The difficult part would be get the device put through a factory reset. This might be accomplished through social engineering of data center staff. Most locked cages have ventilation holes, and possibly a long "paperclip" could reach through to depress a factory reset button. Once such a piece of ISP equipment has been compromised, it could be used to compromise equipment that was connected to (through long haul links even), assuming that those pieces of equipment could also be forced through a factory reset.¶
The above scenario seems rather unlikely as it requires some element of physical access; but were there a remote exploit that did not cause a direct breach, but rather a fault that resulted in a factory reset, this could provide a reasonable path.¶
The above deals with ANI uses of BRSKI. For cases where 802.11 or 802.15.4 is involved, the need to connect directly to the device is eliminated, but the need to do a factory reset is not. Physical possession of the device is not required as above, provided that there is some way to force a factory reset. With some consumers devices with low overall implementation quality, the end users might be familiar with needing to reset the device regularly.¶
The authors are unable to come up with an attack scenario where a compromised voucher signature enables an attacker to introduce a compromised pledge into an existing operator's network. This is the case because the operator controls the communication between Registrar and MASA, and there is no opportunity to introduce the fake voucher through that conduit.¶
Once the operator of the MASA realizes that the voucher signing key has been compromised it has to do a few things.¶
First, it MUST issue a firmware update to all devices that had that key as a trust anchor, such that they will no longer trust vouchers from that key. This will affect devices in the field which are operating, but those devices, being in operation, are not performing onboarding operations, so this is not a critical patch.¶
Devices in boxes (in warehouses) are vulnerable, and remain vulnerable until patched. An operator would be prudent to unbox the devices, onboard them in a safe environment, and then perform firmware updates. This does not have to be done by the end-operator; it could be done by a distributor that stores the spares. A recommended practice for high value devices (which typically have a <4hr service window) may be to validate the device operation on a regular basis anyway.¶
If the onboarding process includes attestations about firmware versions, then through that process the operator would be advised to upgrade the firmware before going into production. Unfortunately, this does not help against situations where the attacker operates their own Registrar (as listed above).¶
[RFC8366] section 6.1 explains the need for short-lived vouchers. The nonce guarantees freshness, and the short-lived nature of the voucher means that the window to deliver a fake voucher is very short. A nonceless, long-lived voucher would be the only option for the attacker, and devices in the warehouse would be vulnerable to such a thing.¶
A key operational recommendation is for manufacturers to sign nonceless, long-lived vouchers with a different key that they sign short-lived vouchers. That key needs significantly better protection. If both keys come from a common trust-anchor (the manufacturer's CA), then a compromise of the manufacturer's CA would compromise both keys. Such a compromise of the manufacturer's CA likely compromises all keys outlined in this section.¶
An attacker that takes over the MASA web service has a number of attacks. The most obvious one is simply to take the database listing customers and devices and to sell this data to other attackers who will now know where to find potentially vulnerable devices.¶
The second most obvious thing that the attacker can do is to kill the service, or make it operate unreliably, making customers frustrated. This could have a serious affect on ability to deploy new services by customers, and would be a significant issue during disaster recovery.¶
While the compromise of the MASA web service may lead to the compromise of the MASA voucher signing key, if the signing occurs offboard (such as in a hardware signing module, HSM), then the key may well be safe, but control over it resides with the attacker.¶
Such an attacker can issue vouchers for any device presently in service. Said device still needs to be convinced to do through a factory reset process before an attack.¶
If the attacker has access to a key that is trusted for long-lived nonceless vouchers, then they could issue vouchers for devices which are not yet in service. This attack may be very hard to verify and as it would involve doing firmware updates on every device in warehouses (a potentially ruinously expensive process), a manufacturer might be reluctant to admit this possibility.¶
As described in the Security Considerations section of [RFC8366] (section 7.4), the YANG module specified in this document defines the schema for data that is subsequently encapsulated by a CMS signed-data content type, as described in Section 5 of [RFC5652]. As such, all of the YANG modeled data is protected from modification.¶
The use of YANG to define data structures, via the 'yang-data' statement, is relatively new and distinct from the traditional use of YANG to define an API accessed by network management protocols such as NETCONF [RFC6241] and RESTCONF [RFC8040]. For this reason, these guidelines do not follow template described by Section 3.7 of [RFC8407].¶
We would like to thank the various reviewers for their input, in particular William Atwood, Brian Carpenter, Fuyu Eleven, Eliot Lear, Sergey Kasatkin, Anoop Kumar, Tom Petch, Markus Stenberg, Peter van der Stok, and Thomas Werner¶
Significant reviews were done by Jari Arko, Christian Huitema and Russ Housley.¶
Henk Birkholz contributed the CDDL for the audit log response.¶
This document started it's life as a two-page idea from Steinthor Bjarnason.¶
In addition, significant review comments were received by many IESG members, including Adam Roach, Alexey Melnikov, Alissa Cooper, Benjamin Kaduk, Eric Vyncke, Roman Danyliw, and Magnus Westerlund.¶
The specification of BRSKI in Section 4 intentionally only covers the mechanisms for an IPv6 pledge using Link-Local addresses. This section describes non-normative extensions that can be used in other environments.¶
Instead of an IPv6 link-local address, an IPv4 address may be generated using [RFC3927] Dynamic Configuration of IPv4 Link-Local Addresses.¶
In the case that an IPv4 Link-Local address is formed, then the bootstrap process would continue as in the IPv6 case by looking for a (circuit) proxy.¶
The Pledge MAY obtain an IP address via DHCP [RFC2131]. The DHCP provided parameters for the Domain Name System can be used to perform DNS operations if all local discovery attempts fail.¶
Pledge discovery of the proxy (Section 4.1) MAY be performed with DNS-based Service Discovery [RFC6763] over Multicast DNS [RFC6762] to discover the proxy at "_brski-proxy._tcp.local.".¶
Proxy discovery of the registrar (Section 4.3) MAY be performed with DNS-based Service Discovery over Multicast DNS to discover registrars by searching for the service "_brski-registrar._tcp.local.".¶
To prevent unaccceptable levels of network traffic, when using mDNS, the congestion avoidance mechanisms specified in [RFC6762] section 7 MUST be followed. The pledge SHOULD listen for an unsolicited broadcast response as described in [RFC6762]. This allows devices to avoid announcing their presence via mDNS broadcasts and instead silently join a network by watching for periodic unsolicited broadcast responses.¶
Discovery of registrar MAY also be performed with DNS-based service discovery by searching for the service "_brski-registrar._tcp.<domain>". In this case the domain "example.com" is discovered as described in [RFC6763] section 11 (Appendix A.2 suggests the use of DHCP parameters).¶
If no local proxy or registrar service is located using the GRASP mechanisms or the above mentioned DNS-based Service Discovery methods, the pledge MAY contact a well known manufacturer provided bootstrapping server by performing a DNS lookup using a well known URI such as "brski-registrar.manufacturer.example.com". The details of the URI are manufacturer specific. Manufacturers that leverage this method on the pledge are responsible for providing the registrar service. Also see Section 2.7.¶
The current DNS services returned during each query are maintained until bootstrapping is completed. If bootstrapping fails and the pledge returns to the Discovery state, it picks up where it left off and continues attempting bootstrapping. For example, if the first Multicast DNS _bootstrapks._tcp.local response doesn't work then the second and third responses are tried. If these fail the pledge moves on to normal DNS-based Service Discovery.¶
Three entities are involved in a voucher: the MASA issues (signs) it, the registrar's public key is mentioned in the voucher, and the pledge validates it. In order to provide reproduceable examples the public and private keys for an example MASA and registrar are first listed.¶
The Manufacturer has a Certificate Authority that signs the pledge's IDevID. In addition the Manufacturer's signing authority (the MASA) signs the vouchers, and that certificate must distributed to the devices at manufacturing time so that vouchers can be validated.¶
This private key signs vouchers:¶
-----BEGIN EC PRIVATE KEY----- MIGkAgEBBDAgiRoYqKoEcfOfvRvmZ5P5Azn58tuI7nSnIy7OgFnCeiNo+BmbgMho r6lcU60gwVagBwYFK4EEACKhZANiAATZAH3Rb2FvIJOnts+vXuWW35ofyNbCHzjA zOi2kWZFE1ByurKImNcNMFGirGnRXIXGqWCfw5ICgJ8CuM3vV5ty9bf7KUlOkejz Tvv+5PV++elkP9HQ83vqTAws2WwWTxI= -----END EC PRIVATE KEY-----¶
This public key validates vouchers:¶
-----BEGIN CERTIFICATE----- MIIBzzCCAVagAwIBAgIBATAKBggqhkjOPQQDAjBNMRIwEAYKCZImiZPyLGQBGRYC Y2ExGTAXBgoJkiaJk/IsZAEZFglzYW5kZWxtYW4xHDAaBgNVBAMME1Vuc3RydW5n IEhpZ2h3YXkgQ0EwHhcNMTcwMzI2MTYxOTQwWhcNMTkwMzI2MTYxOTQwWjBHMRIw EAYKCZImiZPyLGQBGRYCY2ExGTAXBgoJkiaJk/IsZAEZFglzYW5kZWxtYW4xFjAU BgNVBAMMDVVuc3RydW5nIE1BU0EwdjAQBgcqhkjOPQIBBgUrgQQAIgNiAATZAH3R b2FvIJOnts+vXuWW35ofyNbCHzjAzOi2kWZFE1ByurKImNcNMFGirGnRXIXGqWCf w5ICgJ8CuM3vV5ty9bf7KUlOkejzTvv+5PV++elkP9HQ83vqTAws2WwWTxKjEDAO MAwGA1UdEwEB/wQCMAAwCgYIKoZIzj0EAwIDZwAwZAIwGb0oyM0doP6t3/LSPL5O DuatEwMYh7WGO+IYTHC8K7EyHBOmCYReKT2+GhV/CLWzAjBNy6UMJTt1tsxJsJqd MPUIFj+4wZg1AOIb/JoA6M7r33pwLQTrHRxEzVMGfWOkYUw= -----END CERTIFICATE-----¶
This private key signs IDevID certificates:¶
-----BEGIN EC PRIVATE KEY----- MIGkAgEBBDAgiRoYqKoEcfOfvRvmZ5P5Azn58tuI7nSnIy7OgFnCeiNo+BmbgMho r6lcU60gwVagBwYFK4EEACKhZANiAATZAH3Rb2FvIJOnts+vXuWW35ofyNbCHzjA zOi2kWZFE1ByurKImNcNMFGirGnRXIXGqWCfw5ICgJ8CuM3vV5ty9bf7KUlOkejz Tvv+5PV++elkP9HQ83vqTAws2WwWTxI= -----END EC PRIVATE KEY-----¶
This public key validates IDevID certificates:¶
-----BEGIN CERTIFICATE----- MIIBzzCCAVagAwIBAgIBATAKBggqhkjOPQQDAjBNMRIwEAYKCZImiZPyLGQBGRYC Y2ExGTAXBgoJkiaJk/IsZAEZFglzYW5kZWxtYW4xHDAaBgNVBAMME1Vuc3RydW5n IEhpZ2h3YXkgQ0EwHhcNMTcwMzI2MTYxOTQwWhcNMTkwMzI2MTYxOTQwWjBHMRIw EAYKCZImiZPyLGQBGRYCY2ExGTAXBgoJkiaJk/IsZAEZFglzYW5kZWxtYW4xFjAU BgNVBAMMDVVuc3RydW5nIE1BU0EwdjAQBgcqhkjOPQIBBgUrgQQAIgNiAATZAH3R b2FvIJOnts+vXuWW35ofyNbCHzjAzOi2kWZFE1ByurKImNcNMFGirGnRXIXGqWCf w5ICgJ8CuM3vV5ty9bf7KUlOkejzTvv+5PV++elkP9HQ83vqTAws2WwWTxKjEDAO MAwGA1UdEwEB/wQCMAAwCgYIKoZIzj0EAwIDZwAwZAIwGb0oyM0doP6t3/LSPL5O DuatEwMYh7WGO+IYTHC8K7EyHBOmCYReKT2+GhV/CLWzAjBNy6UMJTt1tsxJsJqd MPUIFj+4wZg1AOIb/JoA6M7r33pwLQTrHRxEzVMGfWOkYUw= -----END CERTIFICATE-----¶
The registrar key (or chain) is the representative of the domain owner. This key signs registrar voucher-requests:¶
-----BEGIN EC PRIVATE KEY----- MHcCAQEEIF+obiToYYYeMifPsZvrjWJ0yFsCJwIFhpokmT/TULmXoAoGCCqGSM49 AwEHoUQDQgAENWQOzcNMUjP0NrtfeBc0DJLWfeMGgCFdIv6FUz4DifM1ujMBec/g 6W/P6boTmyTGdFOh/8HwKUerL5bpneK8sg== -----END EC PRIVATE KEY-----¶
The public key is indicated in a pledge voucher-request to show proximity.¶
-----BEGIN CERTIFICATE----- MIIBrjCCATOgAwIBAgIBAzAKBggqhkjOPQQDAzBOMRIwEAYKCZImiZPyLGQBGRYC Y2ExGTAXBgoJkiaJk/IsZAEZFglzYW5kZWxtYW4xHTAbBgNVBAMMFFVuc3RydW5n IEZvdW50YWluIENBMB4XDTE3MDkwNTAxMTI0NVoXDTE5MDkwNTAxMTI0NVowQzES MBAGCgmSJomT8ixkARkWAmNhMRkwFwYKCZImiZPyLGQBGRYJc2FuZGVsbWFuMRIw EAYDVQQDDAlsb2NhbGhvc3QwWTATBgcqhkjOPQIBBggqhkjOPQMBBwNCAAQ1ZA7N w0xSM/Q2u194FzQMktZ94waAIV0i/oVTPgOJ8zW6MwF5z+Dpb8/puhObJMZ0U6H/ wfApR6svlumd4ryyow0wCzAJBgNVHRMEAjAAMAoGCCqGSM49BAMDA2kAMGYCMQC3 /iTQJ3evYYcgbXhbmzrp64t3QC6qjIeY2jkDx062nuNifVKtyaara3F30AIkKSEC MQDi29efbTLbdtDk3tecY/rD7V77XaJ6nYCmdDCR54TrSFNLgxvt1lyFM+0fYpYR c3o= -----END CERTIFICATE-----¶
The registrar public certificate as decoded by openssl's x509 utility. Note that the registrar certificate is marked with the cmcRA extension.¶
Certificate: Data: Version: 3 (0x2) Serial Number: 3 (0x3) Signature Algorithm: ecdsa-with-SHA384 Issuer: DC=ca, DC=sandelman, CN=Unstrung Fountain CA Validity Not Before: Sep 5 01:12:45 2017 GMT Not After : Sep 5 01:12:45 2019 GMT Subject: DC=ca, DC=sandelman, CN=localhost Subject Public Key Info: Public Key Algorithm: id-ecPublicKey Public-Key: (256 bit) pub: 04:35:64:0e:cd:c3:4c:52:33:f4:36:bb:5f:7 8:17: 34:0c:92:d6:7d:e3:06:80:21:5d:22:fe:85:5 3:3e: 03:89:f3:35:ba:33:01:79:cf:e0:e9:6f:cf:e 9:ba: 13:9b:24:c6:74:53:a1:ff:c1:f0:29:47:ab:2 f:96: e9:9d:e2:bc:b2 ASN1 OID: prime256v1 X509v3 extensions: X509v3 Basic Constraints: CA:FALSE Signature Algorithm: ecdsa-with-SHA384 30:66:02:31:00:b7:fe:24:d0:27:77:af:61:87:20:6d:78: 5b: 9b:3a:e9:eb:8b:77:40:2e:aa:8c:87:98:da:39:03:c7:4e: b6: 9e:e3:62:7d:52:ad:c9:a6:ab:6b:71:77:d0:02:24:29:21: 02: 31:00:e2:db:d7:9f:6d:32:db:76:d0:e4:de:d7:9c:63:fa: c3: ed:5e:fb:5d:a2:7a:9d:80:a6:74:30:91:e7:84:eb:48:53: 4b: 83:1b:ed:d6:5c:85:33:ed:1f:62:96:11:73:7a¶
NOTE TO THE RFC EDITOR: before publishing, this example will be replaced with an example with the IANA allocated OID rather than 1.3.6.1.4.1.46930.2.¶
The pledge has an IDevID key pair built in at manufacturing time:¶
-----BEGIN EC PRIVATE KEY----- MHcCAQEEIBgR6SV+uEvWfl5zCQWZxWjYbMhXPyNqdHJ3KPh11mm4oAoGCCqGSM49 AwEHoUQDQgAEWi/jqPpRJ0JgWghZRgeZlLKutbXVjmnHb+1AYaEF/YQjE2g5FZV8 KjiR/bkEl+l8M4onIC7KHaXKKkuag9S6Tw== -----END EC PRIVATE KEY-----¶
The public key is used by the registrar to find the MASA. The MASA URL is in an extension described in Section 2.3.¶
-----BEGIN CERTIFICATE----- MIICBDCCAYugAwIBAgIECe20qTAKBggqhkjOPQQDAjBNMRIwEAYKCZImiZPyLGQB GRYCY2ExGTAXBgoJkiaJk/IsZAEZFglzYW5kZWxtYW4xHDAaBgNVBAMME1Vuc3Ry dW5nIEhpZ2h3YXkgQ0EwIBcNMTkwNDI0MDIxNjU4WhgPMjk5OTEyMzEwMDAwMDBa MBwxGjAYBgNVBAUMETAwLWQwLWU1LTAyLTAwLTJkMFkwEwYHKoZIzj0CAQYIKoZI zj0DAQcDQgAEWi/jqPpRJ0JgWghZRgeZlLKutbXVjmnHb+1AYaEF/YQjE2g5FZV8 KjiR/bkEl+l8M4onIC7KHaXKKkuag9S6T6OBhzCBhDAdBgNVHQ4EFgQUj8KYdUoE OvJ0kcOIbjEWwgWdDYkwCQYDVR0TBAIwADArBgNVHREEJDAioCAGCSsGAQQBgu5S AaATDBEwMC1EMC1FNS0wMi0wMC0yRDArBgkrBgEEAYLuUgIEHgwcbWFzYS5ob25l eWR1a2VzLnNhbmRlbG1hbi5jYTAKBggqhkjOPQQDAgNnADBkAjAmvMjmNgjypDhc fynMV3kMuIpSKrYzRWr4g3PtTwXDsAe0oitTTj4QtU1bajhOfTkCMGMNbsW2Q41F z9t6PDVdtOKabBbAP1RVoFTlDQuO9nmLzb5kU+cUqCtPRFZBUXP3kg== -----END CERTIFICATE-----¶
The pledge public certificate as decoded by openssl's x509 utility so that the extensions can be seen. This was version 1.1.1c of the [openssl] library and utility. There is a second Custom Extension is included to provided to contain the EUI48/EUI64 that the pledge will configure as it's layer-2 address (this is non-normative).¶
Certificate: Data: Version: 3 (0x2) Serial Number: 166573225 (0x9edb4a9) Signature Algorithm: ecdsa-with-SHA256 Issuer: DC = ca, DC = sandelman, CN = Unstrung Highway CA Validity Not Before: Apr 24 02:16:58 2019 GMT Not After : Dec 31 00:00:00 2999 GMT Subject: serialNumber = 00-d0-e5-02-00-2d Subject Public Key Info: Public Key Algorithm: id-ecPublicKey Public-Key: (256 bit) pub: 04:5a:2f:e3:a8:fa:51:27:42:60:5a:08:59:46:07: 99:94:b2:ae:b5:b5:d5:8e:69:c7:6f:ed:40:61:a1: 05:fd:84:23:13:68:39:15:95:7c:2a:38:91:fd:b9: 04:97:e9:7c:33:8a:27:20:2e:ca:1d:a5:ca:2a:4b: 9a:83:d4:ba:4f ASN1 OID: prime256v1 NIST CURVE: P-256 X509v3 extensions: X509v3 Subject Key Identifier: 8F:C2:98:75:4A:04:3A:F2:74:91:C3:88:6E:31:16:C2:05:9D:0D:89 X509v3 Basic Constraints: CA:FALSE X509v3 Subject Alternative Name: othername:<unsupported> 1.3.6.1.4.1.46930.2: ..masa.honeydukes.sandelman.ca Signature Algorithm: ecdsa-with-SHA256 30:64:02:30:26:bc:c8:e6:36:08:f2:a4:38:5c:7f:29:cc:57: 79:0c:b8:8a:52:2a:b6:33:45:6a:f8:83:73:ed:4f:05:c3:b0: 07:b4:a2:2b:53:4e:3e:10:b5:4d:5b:6a:38:4e:7d:39:02:30: 63:0d:6e:c5:b6:43:8d:45:cf:db:7a:3c:35:5d:b4:e2:9a:6c: 16:c0:3f:54:55:a0:54:e5:0d:0b:8e:f6:79:8b:cd:be:64:53: e7:14:a8:2b:4f:44:56:41:51:73:f7:92¶
The JSON examples below are wrapped at 60 columns. This results in strings that have newlines in them, which makes them invalid JSON as is. The strings would otherwise be too long, so they need to be unwrapped before processing.¶
As described in Section 5.2, the pledge will sign a pledge voucher-request containing the registrar's public key in the proximity-registrar-cert field. The base64 has been wrapped at 60 characters for presentation reasons.¶
-----BEGIN CMS----- MIIGtQYJKoZIhvcNAQcCoIIGpjCCBqICAQExDTALBglghkgBZQMEAgEwggNRBgkq hkiG9w0BBwGgggNCBIIDPnsiaWV0Zi12b3VjaGVyLXJlcXVlc3Q6dm91Y2hlciI6 eyJhc3NlcnRpb24iOiJwcm94aW1pdHkiLCJjcmVhdGVkLW9uIjoiMjAxOS0wNS0x NVQxNzoyNTo1NS42NDQtMDQ6MDAiLCJzZXJpYWwtbnVtYmVyIjoiMDAtZDAtZTUt MDItMDAtMmQiLCJub25jZSI6IlZPVUZULVd3ckV2ME51QVFFSG9WN1EiLCJwcm94 aW1pdHktcmVnaXN0cmFyLWNlcnQiOiJNSUlCMFRDQ0FWYWdBd0lCQWdJQkFqQUtC Z2dxaGtqT1BRUURBekJ4TVJJd0VBWUtDWkltaVpQeUxHUUJHUllDWTJFeEdUQVhC Z29Ka2lhSmsvSXNaQUVaRmdsellXNWtaV3h0WVc0eFFEQStCZ05WQkFNTU55TThV M2x6ZEdWdFZtRnlhV0ZpYkdVNk1IZ3dNREF3TURBd05HWTVNVEZoTUQ0Z1ZXNXpk SEoxYm1jZ1JtOTFiblJoYVc0Z1EwRXdIaGNOTVRjeE1UQTNNak0wTlRJNFdoY05N VGt4TVRBM01qTTBOVEk0V2pCRE1SSXdFQVlLQ1pJbWlaUHlMR1FCR1JZQ1kyRXhH VEFYQmdvSmtpYUprL0lzWkFFWkZnbHpZVzVrWld4dFlXNHhFakFRQmdOVkJBTU1D V3h2WTJGc2FHOXpkREJaTUJNR0J5cUdTTTQ5QWdFR0NDcUdTTTQ5QXdFSEEwSUFC SlpsVUhJMHVwL2wzZVpmOXZDQmIrbElub0VNRWdjN1JvK1haQ3RqQUkwQ0QxZkpm SlIvaEl5eURtSFd5WWlORmJSQ0g5ZnlhcmZremdYNHAwelRpenFqRFRBTE1Ba0dB MVVkRXdRQ01BQXdDZ1lJS29aSXpqMEVBd01EYVFBd1pnSXhBTFFNTnVyZjh0djUw bFJPRDVEUVhIRU9KSk5XM1FWMmc5UUVkRFNrMk1ZK0FvU3JCU21HU05qaDRvbEVP aEV1TGdJeEFKNG5XZk53K0JqYlptS2lJaVVFY1R3SE1oR1ZYYU1IWS9GN24zOXd3 S2NCQlNPbmROUHFDcE9FTGw2YnEzQ1pxUT09In19oIICCDCCAgQwggGLoAMCAQIC BAnttKkwCgYIKoZIzj0EAwIwTTESMBAGCgmSJomT8ixkARkWAmNhMRkwFwYKCZIm iZPyLGQBGRYJc2FuZGVsbWFuMRwwGgYDVQQDDBNVbnN0cnVuZyBIaWdod2F5IENB MCAXDTE5MDQyNDAyMTY1OFoYDzI5OTkxMjMxMDAwMDAwWjAcMRowGAYDVQQFDBEw MC1kMC1lNS0wMi0wMC0yZDBZMBMGByqGSM49AgEGCCqGSM49AwEHA0IABFov46j6 USdCYFoIWUYHmZSyrrW11Y5px2/tQGGhBf2EIxNoORWVfCo4kf25BJfpfDOKJyAu yh2lyipLmoPUuk+jgYcwgYQwHQYDVR0OBBYEFI/CmHVKBDrydJHDiG4xFsIFnQ2J MAkGA1UdEwQCMAAwKwYDVR0RBCQwIqAgBgkrBgEEAYLuUgGgEwwRMDAtRDAtRTUt MDItMDAtMkQwKwYJKwYBBAGC7lICBB4MHG1hc2EuaG9uZXlkdWtlcy5zYW5kZWxt YW4uY2EwCgYIKoZIzj0EAwIDZwAwZAIwJrzI5jYI8qQ4XH8pzFd5DLiKUiq2M0Vq +INz7U8Fw7AHtKIrU04+ELVNW2o4Tn05AjBjDW7FtkONRc/bejw1XbTimmwWwD9U VaBU5Q0LjvZ5i82+ZFPnFKgrT0RWQVFz95IxggErMIIBJwIBATBVME0xEjAQBgoJ kiaJk/IsZAEZFgJjYTEZMBcGCgmSJomT8ixkARkWCXNhbmRlbG1hbjEcMBoGA1UE AwwTVW5zdHJ1bmcgSGlnaHdheSBDQQIECe20qTALBglghkgBZQMEAgGgaTAYBgkq hkiG9w0BCQMxCwYJKoZIhvcNAQcBMBwGCSqGSIb3DQEJBTEPFw0xOTA1MTUyMTI1 NTVaMC8GCSqGSIb3DQEJBDEiBCAQN2lP7aqwyhmj9qUHt6Qk/SbOTOPXFOwn1wv2 5YGYgDAKBggqhkjOPQQDAgRHMEUCIEYQhHToU0rrhPyQv2fR0TwWePTx2Z1DEhR4 tTl/Dr/ZAiEA47u9+bIz/p6nFJ+wctKHER+ycUzYQF56h9odMo+Ilkc= -----END CMS-----¶
The ASN1 decoding of the artifact:¶
file: examples/vr_00-D0-E5-02-00-2D.pkcs¶
0:d=0 hl=4 l=1717 cons: SEQUENCE 4:d=1 hl=2 l= 9 prim: OBJECT :pkcs7-signedData 15:d=1 hl=4 l=1702 cons: cont [ 0 ] 19:d=2 hl=4 l=1698 cons: SEQUENCE 23:d=3 hl=2 l= 1 prim: INTEGER :01 26:d=3 hl=2 l= 13 cons: SET 28:d=4 hl=2 l= 11 cons: SEQUENCE 30:d=5 hl=2 l= 9 prim: OBJECT :sha256 41:d=3 hl=4 l= 849 cons: SEQUENCE 45:d=4 hl=2 l= 9 prim: OBJECT :pkcs7-data 56:d=4 hl=4 l= 834 cons: cont [ 0 ] 60:d=5 hl=4 l= 830 prim: OCTET STRING :{"ietf-voucher-request:v 894:d=3 hl=4 l= 520 cons: cont [ 0 ] 898:d=4 hl=4 l= 516 cons: SEQUENCE 902:d=5 hl=4 l= 395 cons: SEQUENCE 906:d=6 hl=2 l= 3 cons: cont [ 0 ] 908:d=7 hl=2 l= 1 prim: INTEGER :02 911:d=6 hl=2 l= 4 prim: INTEGER :09EDB4A9 917:d=6 hl=2 l= 10 cons: SEQUENCE 919:d=7 hl=2 l= 8 prim: OBJECT :ecdsa-with-SHA256 929:d=6 hl=2 l= 77 cons: SEQUENCE 931:d=7 hl=2 l= 18 cons: SET 933:d=8 hl=2 l= 16 cons: SEQUENCE 935:d=9 hl=2 l= 10 prim: OBJECT :domainComponent 947:d=9 hl=2 l= 2 prim: IA5STRING :ca 951:d=7 hl=2 l= 25 cons: SET 953:d=8 hl=2 l= 23 cons: SEQUENCE 955:d=9 hl=2 l= 10 prim: OBJECT :domainComponent 967:d=9 hl=2 l= 9 prim: IA5STRING :sandelman 978:d=7 hl=2 l= 28 cons: SET 980:d=8 hl=2 l= 26 cons: SEQUENCE 982:d=9 hl=2 l= 3 prim: OBJECT :commonName 987:d=9 hl=2 l= 19 prim: UTF8STRING :Unstrung Highway CA 1008:d=6 hl=2 l= 32 cons: SEQUENCE 1010:d=7 hl=2 l= 13 prim: UTCTIME :190424021658Z 1025:d=7 hl=2 l= 15 prim: GENERALIZEDTIME :29991231000000Z 1042:d=6 hl=2 l= 28 cons: SEQUENCE 1044:d=7 hl=2 l= 26 cons: SET 1046:d=8 hl=2 l= 24 cons: SEQUENCE 1048:d=9 hl=2 l= 3 prim: OBJECT :serialNumber 1053:d=9 hl=2 l= 17 prim: UTF8STRING :00-d0-e5-02-00-2d 1072:d=6 hl=2 l= 89 cons: SEQUENCE 1074:d=7 hl=2 l= 19 cons: SEQUENCE 1076:d=8 hl=2 l= 7 prim: OBJECT :id-ecPublicKey 1085:d=8 hl=2 l= 8 prim: OBJECT :prime256v1 1095:d=7 hl=2 l= 66 prim: BIT STRING 1163:d=6 hl=3 l= 135 cons: cont [ 3 ] 1166:d=7 hl=3 l= 132 cons: SEQUENCE 1169:d=8 hl=2 l= 29 cons: SEQUENCE 1171:d=9 hl=2 l= 3 prim: OBJECT :X509v3 Subject Key Ident 1176:d=9 hl=2 l= 22 prim: OCTET STRING [HEX DUMP]:04148FC298754A 1200:d=8 hl=2 l= 9 cons: SEQUENCE 1202:d=9 hl=2 l= 3 prim: OBJECT :X509v3 Basic Constraints 1207:d=9 hl=2 l= 2 prim: OCTET STRING [HEX DUMP]:3000 1211:d=8 hl=2 l= 43 cons: SEQUENCE 1213:d=9 hl=2 l= 3 prim: OBJECT :X509v3 Subject Alternati 1218:d=9 hl=2 l= 36 prim: OCTET STRING [HEX DUMP]:3022A02006092B 1256:d=8 hl=2 l= 43 cons: SEQUENCE 1258:d=9 hl=2 l= 9 prim: OBJECT :1.3.6.1.4.1.46930.2 1269:d=9 hl=2 l= 30 prim: OCTET STRING [HEX DUMP]:0C1C6D6173612E 1301:d=5 hl=2 l= 10 cons: SEQUENCE 1303:d=6 hl=2 l= 8 prim: OBJECT :ecdsa-with-SHA256 1313:d=5 hl=2 l= 103 prim: BIT STRING 1418:d=3 hl=4 l= 299 cons: SET 1422:d=4 hl=4 l= 295 cons: SEQUENCE 1426:d=5 hl=2 l= 1 prim: INTEGER :01 1429:d=5 hl=2 l= 85 cons: SEQUENCE 1431:d=6 hl=2 l= 77 cons: SEQUENCE 1433:d=7 hl=2 l= 18 cons: SET 1435:d=8 hl=2 l= 16 cons: SEQUENCE 1437:d=9 hl=2 l= 10 prim: OBJECT :domainComponent 1449:d=9 hl=2 l= 2 prim: IA5STRING :ca 1453:d=7 hl=2 l= 25 cons: SET 1455:d=8 hl=2 l= 23 cons: SEQUENCE 1457:d=9 hl=2 l= 10 prim: OBJECT :domainComponent 1469:d=9 hl=2 l= 9 prim: IA5STRING :sandelman 1480:d=7 hl=2 l= 28 cons: SET 1482:d=8 hl=2 l= 26 cons: SEQUENCE 1484:d=9 hl=2 l= 3 prim: OBJECT :commonName 1489:d=9 hl=2 l= 19 prim: UTF8STRING :Unstrung Highway CA 1510:d=6 hl=2 l= 4 prim: INTEGER :09EDB4A9 1516:d=5 hl=2 l= 11 cons: SEQUENCE 1518:d=6 hl=2 l= 9 prim: OBJECT :sha256 1529:d=5 hl=2 l= 105 cons: cont [ 0 ] 1531:d=6 hl=2 l= 24 cons: SEQUENCE 1533:d=7 hl=2 l= 9 prim: OBJECT :contentType 1544:d=7 hl=2 l= 11 cons: SET 1546:d=8 hl=2 l= 9 prim: OBJECT :pkcs7-data 1557:d=6 hl=2 l= 28 cons: SEQUENCE 1559:d=7 hl=2 l= 9 prim: OBJECT :signingTime 1570:d=7 hl=2 l= 15 cons: SET 1572:d=8 hl=2 l= 13 prim: UTCTIME :190515212555Z 1587:d=6 hl=2 l= 47 cons: SEQUENCE 1589:d=7 hl=2 l= 9 prim: OBJECT :messageDigest 1600:d=7 hl=2 l= 34 cons: SET 1602:d=8 hl=2 l= 32 prim: OCTET STRING [HEX DUMP]:1037694FEDAAB0 1636:d=5 hl=2 l= 10 cons: SEQUENCE 1638:d=6 hl=2 l= 8 prim: OBJECT :ecdsa-with-SHA256 1648:d=5 hl=2 l= 71 prim: OCTET STRING [HEX DUMP]:30450220461084¶
The JSON contained in the voucher request:¶
{"ietf-voucher-request:voucher":{"assertion":"proximity","cr eated-on":"2019-05-15T17:25:55.644-04:00","serial-number":"0 0-d0-e5-02-00-2d","nonce":"VOUFT-WwrEv0NuAQEHoV7Q","proximit y-registrar-cert":"MIIB0TCCAVagAwIBAgIBAjAKBggqhkjOPQQDAzBxM RIwEAYKCZImiZPyLGQBGRYCY2ExGTAXBgoJkiaJk/IsZAEZFglzYW5kZWxtY W4xQDA+BgNVBAMMNyM8U3lzdGVtVmFyaWFibGU6MHgwMDAwMDAwNGY5MTFhM D4gVW5zdHJ1bmcgRm91bnRhaW4gQ0EwHhcNMTcxMTA3MjM0NTI4WhcNMTkxM TA3MjM0NTI4WjBDMRIwEAYKCZImiZPyLGQBGRYCY2ExGTAXBgoJkiaJk/IsZ AEZFglzYW5kZWxtYW4xEjAQBgNVBAMMCWxvY2FsaG9zdDBZMBMGByqGSM49A gEGCCqGSM49AwEHA0IABJZlUHI0up/l3eZf9vCBb+lInoEMEgc7Ro+XZCtjA I0CD1fJfJR/hIyyDmHWyYiNFbRCH9fyarfkzgX4p0zTizqjDTALMAkGA1UdE wQCMAAwCgYIKoZIzj0EAwMDaQAwZgIxALQMNurf8tv50lROD5DQXHEOJJNW3 QV2g9QEdDSk2MY+AoSrBSmGSNjh4olEOhEuLgIxAJ4nWfNw+BjbZmKiIiUEc TwHMhGVXaMHY/F7n39wwKcBBSOndNPqCpOELl6bq3CZqQ=="}}¶
As described in Section 5.5 the registrar will sign a registrar voucher-request, and will include pledge's voucher request in the prior-signed-voucher-request.¶
-----BEGIN CMS----- MIIPkwYJKoZIhvcNAQcCoIIPhDCCD4ACAQExDTALBglghkgBZQMEAgEwggnUBgkq hkiG9w0BBwGgggnFBIIJwXsiaWV0Zi12b3VjaGVyLXJlcXVlc3Q6dm91Y2hlciI6 eyJhc3NlcnRpb24iOiJwcm94aW1pdHkiLCJjcmVhdGVkLW9uIjoiMjAxOS0wNS0x NVQyMToyNTo1NS43NThaIiwic2VyaWFsLW51bWJlciI6IjAwLWQwLWU1LTAyLTAw LTJkIiwibm9uY2UiOiJWT1VGVC1Xd3JFdjBOdUFRRUhvVjdRIiwicHJpb3Itc2ln bmVkLXZvdWNoZXItcmVxdWVzdCI6Ik1JSUd0UVlKS29aSWh2Y05BUWNDb0lJR3Bq Q0NCcUlDQVFFeERUQUxCZ2xnaGtnQlpRTUVBZ0V3Z2dOUkJna3Foa2lHOXcwQkJ3 R2dnZ05DQklJRFBuc2lhV1YwWmkxMmIzVmphR1Z5TFhKbGNYVmxjM1E2ZG05MVky aGxjaUk2ZXlKaGMzTmxjblJwYjI0aU9pSndjbTk0YVcxcGRIa2lMQ0pqY21WaGRH VmtMVzl1SWpvaU1qQXhPUzB3TlMweE5WUXhOem95TlRvMU5TNDJORFF0TURRNk1E QWlMQ0p6WlhKcFlXd3RiblZ0WW1WeUlqb2lNREF0WkRBdFpUVXRNREl0TURBdE1t UWlMQ0p1YjI1alpTSTZJbFpQVlVaVUxWZDNja1YyTUU1MVFWRkZTRzlXTjFFaUxD SndjbTk0YVcxcGRIa3RjbVZuYVhOMGNtRnlMV05sY25RaU9pSk5TVWxDTUZSRFEw RldZV2RCZDBsQ1FXZEpRa0ZxUVV0Q1oyZHhhR3RxVDFCUlVVUkJla0o0VFZKSmQw VkJXVXREV2tsdGFWcFFlVXhIVVVKSFVsbERXVEpGZUVkVVFWaENaMjlLYTJsaFNt 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aNxiJwIxAOCRjtlN+VSmCLTvWwMTxnSpIuqMr/O1y2Z8rl459VRFphWPdbf4i0qE cwu0u4JzpDGCAUwwggFIAgEBMHYwcTESMBAGCgmSJomT8ixkARkWAmNhMRkwFwYK CZImiZPyLGQBGRYJc2FuZGVsbWFuMUAwPgYDVQQDDDcjPFN5c3RlbVZhcmlhYmxl OjB4MDAwMDAwMDRmOTExYTA+IFVuc3RydW5nIEZvdW50YWluIENBAgECMAsGCWCG SAFlAwQCAaBpMBgGCSqGSIb3DQEJAzELBgkqhkiG9w0BBwEwHAYJKoZIhvcNAQkF MQ8XDTE5MDUxNTIxMjU1NVowLwYJKoZIhvcNAQkEMSIEIFBQjMmWzZOEkRHXrVAS snJwgQ26goyvOAtUFYs3MstMMAoGCCqGSM49BAMCBEcwRQIgBthbhEmgbqZbYDkD zxHXLzJ5eusWplzHKqZyxNpzaR8CIQC3UtMu0QsXoUpYL016iTsbd7Eedi8IfnwQ akExfhh0ew== -----END CMS-----¶
The ASN1 decoding of the artifact:¶
file: examples/parboiled_vr_00_D0-E5-02-00-2D.pkcs¶
0:d=0 hl=4 l=3987 cons: SEQUENCE 4:d=1 hl=2 l= 9 prim: OBJECT :pkcs7-signedData 15:d=1 hl=4 l=3972 cons: cont [ 0 ] 19:d=2 hl=4 l=3968 cons: SEQUENCE 23:d=3 hl=2 l= 1 prim: INTEGER :01 26:d=3 hl=2 l= 13 cons: SET 28:d=4 hl=2 l= 11 cons: SEQUENCE 30:d=5 hl=2 l= 9 prim: OBJECT :sha256 41:d=3 hl=4 l=2516 cons: SEQUENCE 45:d=4 hl=2 l= 9 prim: OBJECT :pkcs7-data 56:d=4 hl=4 l=2501 cons: cont [ 0 ] 60:d=5 hl=4 l=2497 prim: OCTET STRING :{"ietf-voucher-request:v 2561:d=3 hl=4 l=1090 cons: cont [ 0 ] 2565:d=4 hl=4 l= 465 cons: SEQUENCE 2569:d=5 hl=4 l= 342 cons: SEQUENCE 2573:d=6 hl=2 l= 3 cons: cont [ 0 ] 2575:d=7 hl=2 l= 1 prim: INTEGER :02 2578:d=6 hl=2 l= 1 prim: INTEGER :02 2581:d=6 hl=2 l= 10 cons: SEQUENCE 2583:d=7 hl=2 l= 8 prim: OBJECT :ecdsa-with-SHA384 2593:d=6 hl=2 l= 113 cons: SEQUENCE 2595:d=7 hl=2 l= 18 cons: SET 2597:d=8 hl=2 l= 16 cons: SEQUENCE 2599:d=9 hl=2 l= 10 prim: OBJECT :domainComponent 2611:d=9 hl=2 l= 2 prim: IA5STRING :ca 2615:d=7 hl=2 l= 25 cons: SET 2617:d=8 hl=2 l= 23 cons: SEQUENCE 2619:d=9 hl=2 l= 10 prim: OBJECT :domainComponent 2631:d=9 hl=2 l= 9 prim: IA5STRING :sandelman 2642:d=7 hl=2 l= 64 cons: SET 2644:d=8 hl=2 l= 62 cons: SEQUENCE 2646:d=9 hl=2 l= 3 prim: OBJECT :commonName 2651:d=9 hl=2 l= 55 prim: UTF8STRING :#<SystemVariable:0x00000 2708:d=6 hl=2 l= 30 cons: SEQUENCE 2710:d=7 hl=2 l= 13 prim: UTCTIME :171107234528Z 2725:d=7 hl=2 l= 13 prim: UTCTIME :191107234528Z 2740:d=6 hl=2 l= 67 cons: SEQUENCE 2742:d=7 hl=2 l= 18 cons: SET 2744:d=8 hl=2 l= 16 cons: SEQUENCE 2746:d=9 hl=2 l= 10 prim: OBJECT :domainComponent 2758:d=9 hl=2 l= 2 prim: IA5STRING :ca 2762:d=7 hl=2 l= 25 cons: SET 2764:d=8 hl=2 l= 23 cons: SEQUENCE 2766:d=9 hl=2 l= 10 prim: OBJECT :domainComponent 2778:d=9 hl=2 l= 9 prim: IA5STRING :sandelman 2789:d=7 hl=2 l= 18 cons: SET 2791:d=8 hl=2 l= 16 cons: SEQUENCE 2793:d=9 hl=2 l= 3 prim: OBJECT :commonName 2798:d=9 hl=2 l= 9 prim: UTF8STRING :localhost 2809:d=6 hl=2 l= 89 cons: SEQUENCE 2811:d=7 hl=2 l= 19 cons: SEQUENCE 2813:d=8 hl=2 l= 7 prim: OBJECT :id-ecPublicKey 2822:d=8 hl=2 l= 8 prim: OBJECT :prime256v1 2832:d=7 hl=2 l= 66 prim: BIT STRING 2900:d=6 hl=2 l= 13 cons: cont [ 3 ] 2902:d=7 hl=2 l= 11 cons: SEQUENCE 2904:d=8 hl=2 l= 9 cons: SEQUENCE 2906:d=9 hl=2 l= 3 prim: OBJECT :X509v3 Basic Constraints 2911:d=9 hl=2 l= 2 prim: OCTET STRING [HEX DUMP]:3000 2915:d=5 hl=2 l= 10 cons: SEQUENCE 2917:d=6 hl=2 l= 8 prim: OBJECT :ecdsa-with-SHA384 2927:d=5 hl=2 l= 105 prim: BIT STRING 3034:d=4 hl=4 l= 617 cons: SEQUENCE 3038:d=5 hl=4 l= 495 cons: SEQUENCE 3042:d=6 hl=2 l= 3 cons: cont [ 0 ] 3044:d=7 hl=2 l= 1 prim: INTEGER :02 3047:d=6 hl=2 l= 1 prim: INTEGER :03 3050:d=6 hl=2 l= 10 cons: SEQUENCE 3052:d=7 hl=2 l= 8 prim: OBJECT :ecdsa-with-SHA256 3062:d=6 hl=2 l= 109 cons: SEQUENCE 3064:d=7 hl=2 l= 18 cons: SET 3066:d=8 hl=2 l= 16 cons: SEQUENCE 3068:d=9 hl=2 l= 10 prim: OBJECT :domainComponent 3080:d=9 hl=2 l= 2 prim: IA5STRING :ca 3084:d=7 hl=2 l= 25 cons: SET 3086:d=8 hl=2 l= 23 cons: SEQUENCE 3088:d=9 hl=2 l= 10 prim: OBJECT :domainComponent 3100:d=9 hl=2 l= 9 prim: IA5STRING :sandelman 3111:d=7 hl=2 l= 60 cons: SET 3113:d=8 hl=2 l= 58 cons: SEQUENCE 3115:d=9 hl=2 l= 3 prim: OBJECT :commonName 3120:d=9 hl=2 l= 51 prim: UTF8STRING :fountain-test.example.co 3173:d=6 hl=2 l= 30 cons: SEQUENCE 3175:d=7 hl=2 l= 13 prim: UTCTIME :190113225444Z 3190:d=7 hl=2 l= 13 prim: UTCTIME :210112225444Z 3205:d=6 hl=2 l= 109 cons: SEQUENCE 3207:d=7 hl=2 l= 18 cons: SET 3209:d=8 hl=2 l= 16 cons: SEQUENCE 3211:d=9 hl=2 l= 10 prim: OBJECT :domainComponent 3223:d=9 hl=2 l= 2 prim: IA5STRING :ca 3227:d=7 hl=2 l= 25 cons: SET 3229:d=8 hl=2 l= 23 cons: SEQUENCE 3231:d=9 hl=2 l= 10 prim: OBJECT :domainComponent 3243:d=9 hl=2 l= 9 prim: IA5STRING :sandelman 3254:d=7 hl=2 l= 60 cons: SET 3256:d=8 hl=2 l= 58 cons: SEQUENCE 3258:d=9 hl=2 l= 3 prim: OBJECT :commonName 3263:d=9 hl=2 l= 51 prim: UTF8STRING :fountain-test.example.co 3316:d=6 hl=2 l= 118 cons: SEQUENCE 3318:d=7 hl=2 l= 16 cons: SEQUENCE 3320:d=8 hl=2 l= 7 prim: OBJECT :id-ecPublicKey 3329:d=8 hl=2 l= 5 prim: OBJECT :secp384r1 3336:d=7 hl=2 l= 98 prim: BIT STRING 3436:d=6 hl=2 l= 99 cons: cont [ 3 ] 3438:d=7 hl=2 l= 97 cons: SEQUENCE 3440:d=8 hl=2 l= 15 cons: SEQUENCE 3442:d=9 hl=2 l= 3 prim: OBJECT :X509v3 Basic Constraints 3447:d=9 hl=2 l= 1 prim: BOOLEAN :255 3450:d=9 hl=2 l= 5 prim: OCTET STRING [HEX DUMP]:30030101FF 3457:d=8 hl=2 l= 14 cons: SEQUENCE 3459:d=9 hl=2 l= 3 prim: OBJECT :X509v3 Key Usage 3464:d=9 hl=2 l= 1 prim: BOOLEAN :255 3467:d=9 hl=2 l= 4 prim: OCTET STRING [HEX DUMP]:03020106 3473:d=8 hl=2 l= 29 cons: SEQUENCE 3475:d=9 hl=2 l= 3 prim: OBJECT :X509v3 Subject Key Ident 3480:d=9 hl=2 l= 22 prim: OCTET STRING [HEX DUMP]:0414B9A5F6CB11 3504:d=8 hl=2 l= 31 cons: SEQUENCE 3506:d=9 hl=2 l= 3 prim: OBJECT :X509v3 Authority Key Ide 3511:d=9 hl=2 l= 24 prim: OCTET STRING [HEX DUMP]:30168014B9A5F6 3537:d=5 hl=2 l= 10 cons: SEQUENCE 3539:d=6 hl=2 l= 8 prim: OBJECT :ecdsa-with-SHA256 3549:d=5 hl=2 l= 104 prim: BIT STRING 3655:d=3 hl=4 l= 332 cons: SET 3659:d=4 hl=4 l= 328 cons: SEQUENCE 3663:d=5 hl=2 l= 1 prim: INTEGER :01 3666:d=5 hl=2 l= 118 cons: SEQUENCE 3668:d=6 hl=2 l= 113 cons: SEQUENCE 3670:d=7 hl=2 l= 18 cons: SET 3672:d=8 hl=2 l= 16 cons: SEQUENCE 3674:d=9 hl=2 l= 10 prim: OBJECT :domainComponent 3686:d=9 hl=2 l= 2 prim: IA5STRING :ca 3690:d=7 hl=2 l= 25 cons: SET 3692:d=8 hl=2 l= 23 cons: SEQUENCE 3694:d=9 hl=2 l= 10 prim: OBJECT :domainComponent 3706:d=9 hl=2 l= 9 prim: IA5STRING :sandelman 3717:d=7 hl=2 l= 64 cons: SET 3719:d=8 hl=2 l= 62 cons: SEQUENCE 3721:d=9 hl=2 l= 3 prim: OBJECT :commonName 3726:d=9 hl=2 l= 55 prim: UTF8STRING :#<SystemVariable:0x00000 3783:d=6 hl=2 l= 1 prim: INTEGER :02 3786:d=5 hl=2 l= 11 cons: SEQUENCE 3788:d=6 hl=2 l= 9 prim: OBJECT :sha256 3799:d=5 hl=2 l= 105 cons: cont [ 0 ] 3801:d=6 hl=2 l= 24 cons: SEQUENCE 3803:d=7 hl=2 l= 9 prim: OBJECT :contentType 3814:d=7 hl=2 l= 11 cons: SET 3816:d=8 hl=2 l= 9 prim: OBJECT :pkcs7-data 3827:d=6 hl=2 l= 28 cons: SEQUENCE 3829:d=7 hl=2 l= 9 prim: OBJECT :signingTime 3840:d=7 hl=2 l= 15 cons: SET 3842:d=8 hl=2 l= 13 prim: UTCTIME :190515212555Z 3857:d=6 hl=2 l= 47 cons: SEQUENCE 3859:d=7 hl=2 l= 9 prim: OBJECT :messageDigest 3870:d=7 hl=2 l= 34 cons: SET 3872:d=8 hl=2 l= 32 prim: OCTET STRING [HEX DUMP]:50508CC996CD93 3906:d=5 hl=2 l= 10 cons: SEQUENCE 3908:d=6 hl=2 l= 8 prim: OBJECT :ecdsa-with-SHA256 3918:d=5 hl=2 l= 71 prim: OCTET STRING [HEX DUMP]:3045022006D85B¶
The MASA will return a voucher to the registrar, to be relayed to the pledge.¶
-----BEGIN CMS----- MIIGsgYJKoZIhvcNAQcCoIIGozCCBp8CAQExDTALBglghkgBZQMEAgEwggNABgkq hkiG9w0BBwGgggMxBIIDLXsiaWV0Zi12b3VjaGVyOnZvdWNoZXIiOnsiYXNzZXJ0 aW9uIjoibG9nZ2VkIiwiY3JlYXRlZC1vbiI6IjIwMTktMDUtMTZUMDI6NTE6NDIu Njk3KzAwOjAwIiwic2VyaWFsLW51bWJlciI6IjAwLWQwLWU1LTAyLTAwLTJkIiwi bm9uY2UiOiJHWmUtT2pvZXJwS0VNNFNNN1N6UzlnIiwicGlubmVkLWRvbWFpbi1j ZXJ0IjoiTUlJQjBUQ0NBVmFnQXdJQkFnSUJBakFLQmdncWhrak9QUVFEQXpCeE1S SXdFQVlLQ1pJbWlaUHlMR1FCR1JZQ1kyRXhHVEFYQmdvSmtpYUprL0lzWkFFWkZn bHpZVzVrWld4dFlXNHhRREErQmdOVkJBTU1OeU04VTNsemRHVnRWbUZ5YVdGaWJH VTZNSGd3TURBd01EQXdOR1k1TVRGaE1ENGdWVzV6ZEhKMWJtY2dSbTkxYm5SaGFX NGdRMEV3SGhjTk1UY3hNVEEzTWpNME5USTRXaGNOTVRreE1UQTNNak0wTlRJNFdq QkRNUkl3RUFZS0NaSW1pWlB5TEdRQkdSWUNZMkV4R1RBWEJnb0praWFKay9Jc1pB RVpGZ2x6WVc1a1pXeHRZVzR4RWpBUUJnTlZCQU1NQ1d4dlkyRnNhRzl6ZERCWk1C TUdCeXFHU000OUFnRUdDQ3FHU000OUF3RUhBMElBQkpabFVISTB1cC9sM2VaZjl2 Q0JiK2xJbm9FTUVnYzdSbytYWkN0akFJMENEMWZKZkpSL2hJeXlEbUhXeVlpTkZi UkNIOWZ5YXJma3pnWDRwMHpUaXpxakRUQUxNQWtHQTFVZEV3UUNNQUF3Q2dZSUtv Wkl6ajBFQXdNRGFRQXdaZ0l4QUxRTU51cmY4dHY1MGxST0Q1RFFYSEVPSkpOVzNR VjJnOVFFZERTazJNWStBb1NyQlNtR1NOamg0b2xFT2hFdUxnSXhBSjRuV2ZOdytC amJabUtpSWlVRWNUd0hNaEdWWGFNSFkvRjduMzl3d0tjQkJTT25kTlBxQ3BPRUxs NmJxM0NacVE9PSJ9faCCAfUwggHxMIIBeKADAgECAgQjzIkTMAoGCCqGSM49BAMC ME0xEjAQBgoJkiaJk/IsZAEZFgJjYTEZMBcGCgmSJomT8ixkARkWCXNhbmRlbG1h bjEcMBoGA1UEAwwTVW5zdHJ1bmcgSGlnaHdheSBDQTAeFw0xOTA0MjMyMzIxMDda Fw0xOTA1MjQwOTIxMDdaMGYxDzANBgNVBAYTBkNhbmFkYTESMBAGA1UECgwJU2Fu ZGVsbWFuMRMwEQYDVQQLDApob25leWR1a2VzMSowKAYDVQQDDCFtYXNhLmhvbmV5 ZHVrZXMuc2FuZGVsbWFuLmNhIE1BU0EwdjAQBgcqhkjOPQIBBgUrgQQAIgNiAAQ1 /2UdVp8zVmgADoBNql7LcPlJsEaaVAogYEqABikNOkoTO3oPjIQfNBxtGfRFzBXx gihzkTH58r8SW1L/Mej8AFqhB4SZyyjmWURdzD71Ju0M+tRritWf7T+QGaE+fcWj EDAOMAwGA1UdEwEB/wQCMAAwCgYIKoZIzj0EAwIDZwAwZAIwOMlNOMNYEZo4yLW4 iRltDL8uirmjMdtVmmVYzqYHSindjP0a3pXQkQZ5LLARoSRWAjBTxsnv6ya5HpZI IWcspDPZGlOSDPm7nuRJSDkgWqevxLI4+9nmIhsfMBsDvz1DJhAxggFMMIIBSAIB ATBVME0xEjAQBgoJkiaJk/IsZAEZFgJjYTEZMBcGCgmSJomT8ixkARkWCXNhbmRl bG1hbjEcMBoGA1UEAwwTVW5zdHJ1bmcgSGlnaHdheSBDQQIEI8yJEzALBglghkgB ZQMEAgGgaTAYBgkqhkiG9w0BCQMxCwYJKoZIhvcNAQcBMBwGCSqGSIb3DQEJBTEP Fw0xOTA1MTYwMjUxNDJaMC8GCSqGSIb3DQEJBDEiBCCYRh4i21QjEjEk8leRLSVA x/EVY5g1bM40QM21oR4c2DAKBggqhkjOPQQDAgRoMGYCMQCYYOiSbIlED4nAN0iL e4S8ixWAZ9SXpGv77bB/G4fTTVTN35mnAeYBfeNfhC6/kOECMQDqlkCmwQJQDdEL asj1ISinJ/FnZjjgOMz9MXOmGNGIfw9v2VBb9mVyhsOSMcqlVig= -----END CMS-----¶
The ASN1 decoding of the artifact:¶
file: examples/voucher_00-D0-E5-02-00-2D.pkcs¶
0:d=0 hl=4 l=1714 cons: SEQUENCE 4:d=1 hl=2 l= 9 prim: OBJECT :pkcs7-signedData 15:d=1 hl=4 l=1699 cons: cont [ 0 ] 19:d=2 hl=4 l=1695 cons: SEQUENCE 23:d=3 hl=2 l= 1 prim: INTEGER :01 26:d=3 hl=2 l= 13 cons: SET 28:d=4 hl=2 l= 11 cons: SEQUENCE 30:d=5 hl=2 l= 9 prim: OBJECT :sha256 41:d=3 hl=4 l= 832 cons: SEQUENCE 45:d=4 hl=2 l= 9 prim: OBJECT :pkcs7-data 56:d=4 hl=4 l= 817 cons: cont [ 0 ] 60:d=5 hl=4 l= 813 prim: OCTET STRING :{"ietf-voucher:voucher": 877:d=3 hl=4 l= 501 cons: cont [ 0 ] 881:d=4 hl=4 l= 497 cons: SEQUENCE 885:d=5 hl=4 l= 376 cons: SEQUENCE 889:d=6 hl=2 l= 3 cons: cont [ 0 ] 891:d=7 hl=2 l= 1 prim: INTEGER :02 894:d=6 hl=2 l= 4 prim: INTEGER :23CC8913 900:d=6 hl=2 l= 10 cons: SEQUENCE 902:d=7 hl=2 l= 8 prim: OBJECT :ecdsa-with-SHA256 912:d=6 hl=2 l= 77 cons: SEQUENCE 914:d=7 hl=2 l= 18 cons: SET 916:d=8 hl=2 l= 16 cons: SEQUENCE 918:d=9 hl=2 l= 10 prim: OBJECT :domainComponent 930:d=9 hl=2 l= 2 prim: IA5STRING :ca 934:d=7 hl=2 l= 25 cons: SET 936:d=8 hl=2 l= 23 cons: SEQUENCE 938:d=9 hl=2 l= 10 prim: OBJECT :domainComponent 950:d=9 hl=2 l= 9 prim: IA5STRING :sandelman 961:d=7 hl=2 l= 28 cons: SET 963:d=8 hl=2 l= 26 cons: SEQUENCE 965:d=9 hl=2 l= 3 prim: OBJECT :commonName 970:d=9 hl=2 l= 19 prim: UTF8STRING :Unstrung Highway CA 991:d=6 hl=2 l= 30 cons: SEQUENCE 993:d=7 hl=2 l= 13 prim: UTCTIME :190423232107Z 1008:d=7 hl=2 l= 13 prim: UTCTIME :190524092107Z 1023:d=6 hl=2 l= 102 cons: SEQUENCE 1025:d=7 hl=2 l= 15 cons: SET 1027:d=8 hl=2 l= 13 cons: SEQUENCE 1029:d=9 hl=2 l= 3 prim: OBJECT :countryName 1034:d=9 hl=2 l= 6 prim: PRINTABLESTRING :Canada 1042:d=7 hl=2 l= 18 cons: SET 1044:d=8 hl=2 l= 16 cons: SEQUENCE 1046:d=9 hl=2 l= 3 prim: OBJECT :organizationName 1051:d=9 hl=2 l= 9 prim: UTF8STRING :Sandelman 1062:d=7 hl=2 l= 19 cons: SET 1064:d=8 hl=2 l= 17 cons: SEQUENCE 1066:d=9 hl=2 l= 3 prim: OBJECT :organizationalUnitName 1071:d=9 hl=2 l= 10 prim: UTF8STRING :honeydukes 1083:d=7 hl=2 l= 42 cons: SET 1085:d=8 hl=2 l= 40 cons: SEQUENCE 1087:d=9 hl=2 l= 3 prim: OBJECT :commonName 1092:d=9 hl=2 l= 33 prim: UTF8STRING :masa.honeydukes.sandelma 1127:d=6 hl=2 l= 118 cons: SEQUENCE 1129:d=7 hl=2 l= 16 cons: SEQUENCE 1131:d=8 hl=2 l= 7 prim: OBJECT :id-ecPublicKey 1140:d=8 hl=2 l= 5 prim: OBJECT :secp384r1 1147:d=7 hl=2 l= 98 prim: BIT STRING 1247:d=6 hl=2 l= 16 cons: cont [ 3 ] 1249:d=7 hl=2 l= 14 cons: SEQUENCE 1251:d=8 hl=2 l= 12 cons: SEQUENCE 1253:d=9 hl=2 l= 3 prim: OBJECT :X509v3 Basic Constraints 1258:d=9 hl=2 l= 1 prim: BOOLEAN :255 1261:d=9 hl=2 l= 2 prim: OCTET STRING [HEX DUMP]:3000 1265:d=5 hl=2 l= 10 cons: SEQUENCE 1267:d=6 hl=2 l= 8 prim: OBJECT :ecdsa-with-SHA256 1277:d=5 hl=2 l= 103 prim: BIT STRING 1382:d=3 hl=4 l= 332 cons: SET 1386:d=4 hl=4 l= 328 cons: SEQUENCE 1390:d=5 hl=2 l= 1 prim: INTEGER :01 1393:d=5 hl=2 l= 85 cons: SEQUENCE 1395:d=6 hl=2 l= 77 cons: SEQUENCE 1397:d=7 hl=2 l= 18 cons: SET 1399:d=8 hl=2 l= 16 cons: SEQUENCE 1401:d=9 hl=2 l= 10 prim: OBJECT :domainComponent 1413:d=9 hl=2 l= 2 prim: IA5STRING :ca 1417:d=7 hl=2 l= 25 cons: SET 1419:d=8 hl=2 l= 23 cons: SEQUENCE 1421:d=9 hl=2 l= 10 prim: OBJECT :domainComponent 1433:d=9 hl=2 l= 9 prim: IA5STRING :sandelman 1444:d=7 hl=2 l= 28 cons: SET 1446:d=8 hl=2 l= 26 cons: SEQUENCE 1448:d=9 hl=2 l= 3 prim: OBJECT :commonName 1453:d=9 hl=2 l= 19 prim: UTF8STRING :Unstrung Highway CA 1474:d=6 hl=2 l= 4 prim: INTEGER :23CC8913 1480:d=5 hl=2 l= 11 cons: SEQUENCE 1482:d=6 hl=2 l= 9 prim: OBJECT :sha256 1493:d=5 hl=2 l= 105 cons: cont [ 0 ] 1495:d=6 hl=2 l= 24 cons: SEQUENCE 1497:d=7 hl=2 l= 9 prim: OBJECT :contentType 1508:d=7 hl=2 l= 11 cons: SET 1510:d=8 hl=2 l= 9 prim: OBJECT :pkcs7-data 1521:d=6 hl=2 l= 28 cons: SEQUENCE 1523:d=7 hl=2 l= 9 prim: OBJECT :signingTime 1534:d=7 hl=2 l= 15 cons: SET 1536:d=8 hl=2 l= 13 prim: UTCTIME :190516025142Z 1551:d=6 hl=2 l= 47 cons: SEQUENCE 1553:d=7 hl=2 l= 9 prim: OBJECT :messageDigest 1564:d=7 hl=2 l= 34 cons: SET 1566:d=8 hl=2 l= 32 prim: OCTET STRING [HEX DUMP]:98461E22DB5423 1600:d=5 hl=2 l= 10 cons: SEQUENCE 1602:d=6 hl=2 l= 8 prim: OBJECT :ecdsa-with-SHA256 1612:d=5 hl=2 l= 104 prim: OCTET STRING [HEX DUMP]:30660231009860¶
RFC EDITOR Please remove this section before publication. It exists just to include references to the things in the YANG descriptions which are not otherwise referenced in the text so that xml2rfc will not complain.¶