Network File System Version 4 T. Myklebust
Internet-Draft Hammerspace
Updates: 5531 (if approved) C. Lever, Ed.
Intended status: Standards Track Oracle
Expires: October 17, 2019 April 15, 2019
Remote Procedure Call Encryption By Default
draft-ietf-nfsv4-rpc-tls-01
Abstract
This document describes a mechanism that opportunistically enables
encryption of in-transit Remote Procedure Call (RPC) transactions
with minimal administrative overhead and full interoperation with ONC
RPC implementations that do not support this mechanism. This
document updates RFC 5531.
Status of This Memo
This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79.
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This Internet-Draft will expire on October 17, 2019.
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3
2. Requirements Language . . . . . . . . . . . . . . . . . . . . 4
3. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 4
4. RPC-Over-TLS in Operation . . . . . . . . . . . . . . . . . . 5
4.1. Discovering Server-side TLS Support . . . . . . . . . . . 5
4.2. Authentication . . . . . . . . . . . . . . . . . . . . . 7
4.2.1. Using TLS with RPCSEC GSS . . . . . . . . . . . . . . 7
5. TLS Requirements . . . . . . . . . . . . . . . . . . . . . . 8
5.1. Connection Types . . . . . . . . . . . . . . . . . . . . 8
5.1.1. Operation on TCP . . . . . . . . . . . . . . . . . . 8
5.1.2. Operation on UDP . . . . . . . . . . . . . . . . . . 8
5.1.3. Operation on an RDMA Transport . . . . . . . . . . . 9
5.2. TLS Peer Authentication . . . . . . . . . . . . . . . . . 9
5.2.1. X.509 Certificates Using PKIX trust . . . . . . . . . 9
5.2.2. X.509 Certificates Using Fingerprints . . . . . . . . 10
5.2.3. Pre-Shared Keys . . . . . . . . . . . . . . . . . . . 10
5.2.4. Token Binding . . . . . . . . . . . . . . . . . . . . 11
6. Implementation Status . . . . . . . . . . . . . . . . . . . . 11
6.1. Linux NFS server and client . . . . . . . . . . . . . . . 11
6.2. DESY NFS server . . . . . . . . . . . . . . . . . . . . . 11
7. Security Considerations . . . . . . . . . . . . . . . . . . . 12
7.1. Implications for AUTH_SYS . . . . . . . . . . . . . . . . 12
7.2. STRIPTLS Attacks . . . . . . . . . . . . . . . . . . . . 13
8. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 13
9. References . . . . . . . . . . . . . . . . . . . . . . . . . 13
9.1. Normative References . . . . . . . . . . . . . . . . . . 13
9.2. Informative References . . . . . . . . . . . . . . . . . 15
Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . . 16
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 16
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1. Introduction
In 2014 the IETF published [RFC7258] which recognized that
unauthorized observation of network traffic had become widespread and
was a subversive threat to all who make use of the Internet at large.
It strongly recommended that newly defined Internet protocols make a
real effort to mitigate monitoring attacks. Typically this
mitigation is done by encrypting data in transit.
The Remote Procedure Call version 2 protocol has been a Proposed
Standard for three decades (see [RFC5531] and its antecedants).
Eisler et al. first introduced an in-transit encryption mechanism for
RPC with RPCSEC GSS over twenty years ago [RFC2203]. However,
experience has shown that RPCSEC GSS can be difficult to deploy:
o Per-client deployment and administrative costs are not scalable.
Keying material must be provided for each RPC client, including
transient clients.
o Parts of each RPC header remain in clear-text, and can constitute
a significant security exposure.
o Host identity management and user identity management must be
carried out in the same security realm. In certain environments,
different authorities might be responsible for provisioning client
systems versus provisioning new users.
o On-host cryptographic manipulation of data payloads can exact a
significant CPU and memory bandwidth cost on RPC peers. Offloadng
does not appear to be practical using GSS privacy since each
message is encrypted using its own key based on the issuing RPC
user.
However strong a privacy service is, it cannot provide any security
if the challenges of using it result in it not being used at all.
An alternative approach is to employ a transport layer security
mechanism that can protect the privacy of each RPC connection
transparently to RPC and Upper Layer protocols. The Transport Layer
Security protocol [RFC8446] (TLS) is a well-established Internet
building block that protects many common Internet protocols such as
the Hypertext Transport Protocol (http) [RFC2818].
Encrypting at the RPC transport layer enables several significant
benefits.
Encryption By Default
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In-transit encryption by itself may be enabled without additional
administrative actions such as identifying client systems to a
trust authority, generating additional key material, or
provisioning a secure network tunnel.
Protection of Existing Protocols
The imposition of encryption at the transport layer protects any
Upper Layer protocol that employs RPC, without alteration of that
protocol. RPC transport layer encryption can protect recent
versions of NFS such as NFS version 4.2 [RFC7862] and indeed
legacy NFS versions such as NFS version 3 [RFC1813], and NFS side-
band protocols such as the MNT protocol [RFC1813].
Decoupled User and Host Identities
TLS can be used to authenticate peer hosts while other security
mechanisms can handle user authentictation. Cryptographic
authentication of hosts can be provided while still using simpler
user authentication flavors such as AUTH_SYS.
Encryption Offload
Whereas hardware support for GSS privacy has not appeared in the
marketplace, the use of a well-established transport encryption
mechanism that is also employed by other very common network
protocols makes it likely that a hardware encryption
implementation will be available to offload encryption and
decryption. A single key protects all messages associated with
one TLS session.
Securing AUTH_SYS
Most critically, several security issues inherent in the current
widespread use of AUTH_SYS (i.e., acceptance of UIDs and GIDs
generated by an unauthenticated client) can be significantly
ameliorated.
2. Requirements Language
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.
3. Terminology
This document adopts the terminology introduced in Section 3 of
[RFC6973] and assumes a working knowledge of the Remote Procedure
Call (RPC) version 2 protocol [RFC5531] and the Transport Layer
Security (TLS) version 1.3 protocol [RFC8446].
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Note also that the NFS community uses the term "privacy" where other
Internet communities use "confidentiality". In this document the two
terms are synonymous.
We cleave to the convention that a "client" is a network host that
actively initiates an association, and a "server" is a network host
that passively accepts an association request.
RPC documentation historically refers to the authentication of a
connecting host as "machine authentication". TLS documentation
refers to the same as "peer authentication". In this document there
is little distinction.
The term "user authentication" in this document refers specifically
to RPC users; i.e., the process owner of the application which is
using RPC.
4. RPC-Over-TLS in Operation
4.1. Discovering Server-side TLS Support
The mechanism described in this document interoperates fully with RPC
implementations that do not support TLS. The use of TLS is
automatically disabled in these cases.
To achieve this, we introduce a new RPC authentication flavor called
AUTH_TLS. This new flavor is used to signal that the client wants to
initiate TLS negotiation if the server supports it. Except for the
modifications described in this section, the RPC protocol is largely
unaware of security encapsulation.
<CODE BEGINS>
enum auth_flavor {
AUTH_NONE = 0,
AUTH_SYS = 1,
AUTH_SHORT = 2,
AUTH_DH = 3,
AUTH_KERB = 4,
AUTH_RSA = 5,
RPCSEC_GSS = 6,
AUTH_TLS = 7,
/* and more to be defined */
};
<CODE ENDS>
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The length of the opaque data constituting the credential sent in the
call message MUST be zero. The verifier accompanying the credential
MUST be an AUTH_NONE verifier of length zero.
The flavor value of the verifier received in the reply message from
the server MUST be AUTH_NONE. The bytes of the verifier's string
encode the fixed ASCII characters "STARTTLS".
When an RPC client is ready to begin sending traffic to a server, it
starts with a NULL RPC request with an auth_flavor of AUTH_TLS. The
NULL request is made to the same port as if TLS were not in use.
The RPC server can respond in one of three ways:
o If the RPC server does not recognise the AUTH_TLS authentication
flavor, it responds with a reject_stat of AUTH_ERROR. The RPC
client then knows that this server does not support TLS.
o If the RPC server accepts the NULL RPC procedure, but fails to
return an AUTH_NONE verifier containing the string "STARTTLS", the
RPC client knows that this server does not support TLS.
o If the RPC server accepts the NULL RPC procedure, and returns an
AUTH_NONE verifier containing the string "STARTTLS", the RPC
client SHOULD send a STARTTLS.
Once the TLS handshake is complete, the RPC client and server will
have established a secure channel for communicating. The client MUST
switch to a security flavor other than AUTH_TLS within that channel,
presumably after negotiating down redundant RPCSEC_GSS privacy and
integrity services and applying channel binding [RFC7861].
If TLS negotiation fails for any reason -- say, the RPC server
rejects the certificate presented by the RPC client, or the RPC
client fails to authenticate the RPC server -- the RPC client reports
this failure to the calling application the same way it would report
an AUTH_ERROR rejection from the RPC server.
If an RPC client attempts to use AUTH_TLS for anything other than the
NULL RPC procedure, the RPC server MUST respond with a reject_stat of
AUTH_ERROR. If the client sends a STARTTLS after it has sent other
non-encrypted RPC traffic or after a TLS session has already been
negotiated, the server MUST silently discard it.
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4.2. Authentication
Both RPC and TLS have their own variants of authentication, and there
is some overlap in capability. The goal of interoperability with
implementations that do not support TLS requires that we limit the
combinations that are allowed and precisely specify the role that
each layer plays. We also want to handle TLS such that an RPC
implementation can make the use of TLS invisible to existing RPC
consumer applications.
Depending on its configuration, an RPC server MAY request a TLS
identity from each client upon first contact. This permits two
different modes of deployment:
Server-only Host Authentication
A server possesses a unique global identity (e.g., a certificate
that is signed by a well-known trust anchor) while its clients are
anonymous (i.e., present no identifier). In this situation, the
client SHOULD authenticate the server host using the presented TLS
identity, but the server cannot authenticate clients.
Mutual Host Authentication
In this type of deployment, both the server and its clients
possess unique identities (e.g., certificates). As part of the
TLS handshake, both peers SHOULD authenticate using the presented
TLS identities. Should authentication of either peer fail, or
should authorization based on those identities block access to the
server, the client association MAY be rejected.
In either of these modes, RPC user authentication is not affected by
the use of transport layer security. Once a TLS session is
established, the server MUST NOT utilize the client peer's TLS
identity for the purpose of authorizing individual RPC requests.
4.2.1. Using TLS with RPCSEC GSS
RPCSEC GSS can provide per-request integrity or privacy (also known
as confidentiality) services. When operating over a TLS session,
these services become redundant. Each RPC implementation is
responsible for using channel binding for detecting when GSS
integrity or privacy is unnecessary and can therefore be disabled.
See Section 2.5 of [RFC7861] for details.
Note that a GSS service principal is still required on the server,
and mutual GSS authentication of server and client still occurs after
the TLS session is established.
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5. TLS Requirements
When a TLS session is negotiated for the purpose of transporting RPC,
the following restrictions apply:
o Implementations MUST NOT negotiate TLS versions prior to v1.3
[RFC8446]. Support for mandatory-to-implement ciphersuites for
the negotiated TLS version is REQUIRED.
o Implementations MUST support certificate-based mutual
authentication. Support for TLS-PSK mutual authentication
[RFC4279] is OPTIONAL. See Section 4.2 for further details.
o Negotiation of a ciphersuite providing for confidentiality as well
as integrity protection is REQUIRED. Support for and negotiation
of compression is OPTIONAL.
5.1. Connection Types
5.1.1. Operation on TCP
RPC over TCP is protected by using TLS [RFC8446]. As soon as a
client completes the TCP handshake, it uses the mechanism described
in Section 4.1 to discover TLS support and then negotiate a TLS
session.
An RPC client terminates a TLS session by sending a TLS closure
alert, or by closing the underlying TCP socket. After TLS session
termination, any subsequent RPC request over the same socket MUST
fail with a reject_stat of AUTH_ERROR.
5.1.2. Operation on UDP
RPC over UDP is protected using DTLS [RFC6347]. As soon as a client
initializes a socket for use with an unfamiliar server, it uses the
mechanism described in Section 4.1 to discover DTLS support and then
negotiate a DTLS session. Connected operation is RECOMMENDED.
Using a DTLS transport does not introduce reliable or in-order
semantics to RPC on UDP. Also, DTLS does not support fragmentation
of RPC messages. One RPC message fits in a single DTLS datagram.
DTLS encapsulation has overhead which reduces the effective Path MTU
(PMTU) and thus the maximum RPC payload size.
DTLS does not detect STARTTLS replay. A DTLS session can be
terminated by sending a TLS closure alert. Subsequent RPC messages
passing between the client and server will no longer be protected
until a new TLS session is established.
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5.1.3. Operation on an RDMA Transport
RPC-over-RDMA can make use of Transport Layer Security below the RDMA
transport layer [RFC8166]. The exact mechanism is not within the
scope of this document.
5.2. TLS Peer Authentication
Peer authentication can be performed by TLS using any of the
following mechanisms:
5.2.1. X.509 Certificates Using PKIX trust
Implementations are REQUIRED to support this mechanism. In this
mode, an RPC peer is uniquely identified by the tuple (serial number
of presented certificate;Issuer).
o Implementations MUST allow the configuration of a list of trusted
Certification Authorities for incoming connections.
o Certificate validation MUST include the verification rules as per
[RFC5280].
o Implementations SHOULD indicate their trusted Certification
Authorities (CAs).
o Peer validation always includes a check on whether the locally
configured expected DNS name or IP address of the server that is
contacted matches its presented certificate. DNS names and IP
addresses can be contained in the Common Name (CN) or
subjectAltName entries. For verification, only one of these
entries is to be considered. The following precedence applies:
for DNS name validation, subjectAltName:DNS has precedence over
CN; for IP address validation, subjectAltName:iPAddr has
precedence over CN. Implementors of this specification are
advised to read Section 6 of [RFC6125] for more details on DNS
name validation.
o Implementations MAY allow the configuration of a set of additional
properties of the certificate to check for a peer's authorization
to communicate (e.g., a set of allowed values in
subjectAltName:URI or a set of allowed X509v3 Certificate
Policies).
o When the configured trust base changes (e.g., removal of a CA from
the list of trusted CAs; issuance of a new CRL for a given CA),
implementations MAY renegotiate the TLS session to reassess the
connecting peer's continued authorization.
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Authenticating a connecting entity does not mean the RPC server
necessarily wants to communicate with that client. For example, if
the Issuer is not in a trusted set of Issuers, the RPC server may
decline to perform RPC transactions with this client.
Implementations that want to support a wide variety of trust models
should expose as many details of the presented certificate to the
administrator as possible so that the trust model can be implemented
by the administrator. As a suggestion, at least the following
parameters of the X.509 client certificate should be exposed:
o Originating IP address
o Certificate Fingerprint
o Issuer
o Subject
o all X509v3 Extended Key Usage
o all X509v3 Subject Alternative Name
o all X509v3 Certificate Policies
5.2.2. X.509 Certificates Using Fingerprints
This mechanism is OPTIONAL to implement. In this mode, an RPC peer
is uniquely identified by the fingerprint of the presented
certificate.
Implementations SHOULD allow the configuration of a list of trusted
certificates, identified via fingerprint of the DER encoded
certificate octets. Implementations MUST support SHA-1 as the hash
algorithm for the fingerprint. To prevent attacks based on hash
collisions, support for a more contemporary hash function, such as
SHA-256, is RECOMMENDED.
5.2.3. Pre-Shared Keys
This mechanism is OPTIONAL to implement. In this mode, an RPC peer
is uniquely identified by key material that has been shared out-of-
band or by a previous TLS-protected connection (see [RFC8446]
Section 2.2). At least the following parameters of the TLS
connection should be exposed:
o Originating IP address
o TLS Identifier
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5.2.4. Token Binding
This mechanism is OPTIONAL to implement. In this mode, an RPC peer
is uniquely identified by a token.
Versions of TLS subsequent to TLS 1.2 feature a token binding
mechanism which is nominally more secure than using certificates.
This is discussed in further detail in [RFC8471].
6. Implementation Status
This section records the status of known implementations of the
protocol defined by this specification at the time of posting of this
Internet-Draft, and is based on a proposal described in [RFC7942].
The description of implementations in this section is intended to
assist the IETF in its decision processes in progressing drafts to
RFCs.
Please note that the listing of any individual implementation here
does not imply endorsement by the IETF. Furthermore, no effort has
been spent to verify the information presented here that was supplied
by IETF contributors. This is not intended as, and must not be
construed to be, a catalog of available implementations or their
features. Readers are advised to note that other implementations may
exist.
6.1. Linux NFS server and client
Organization: The Linux Foundation
URL: https://www.kernel.org
Maturity: Prototype software based on early versions of this
document.
Coverage: The bulk of this specification is implemented. The use of
DTLS functionality is not implemented.
Licensing: GPLv2
Implementation experience: No comments from implementors.
6.2. DESY NFS server
Organization: DESY
URL: https://desy.de
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Maturity: Prototype software based on early versions of this
document.
Coverage: The bulk of this specification is implemented. The use of
DTLS functionality is not implemented.
Licensing: Freely distributable with acknowledgment.
Implementation experience: No comments from implementors.
7. Security Considerations
One purpose of the mechanism described in this document is to protect
RPC-based applications against threats to the privacy of RPC
transactions and RPC user identities. A taxonomy of these threats
appears in Section 5 of [RFC6973]. In addition, Section 6 of
[RFC7525] contains a detailed discussion of technologies used in
conjunction with TLS. Implementers should familiarize themselves
with these materials.
The NFS version 4 protocol permits more than one user to use an NFS
client at the same time [RFC7862]. Typically that NFS client
implementation conserves connection resources by routing RPC
transactions from all of its users over a small number of
connections. In circumstances where the users on that NFS client
belong to multiple distinct security domains, the client MUST
establish independent TLS sessions for each distinct security domain.
7.1. Implications for AUTH_SYS
Ever since the IETF NFSV4 Working Group took over the maintenance of
the NFSv4 family of protocols (currently specified in [RFC7530],
[RFC5661], and [RFC7863], among others), it has encouraged the use of
RPCSEC GSS rather than AUTH_SYS. For various reasons, AUTH_SYS
continues to be the primary authentication mechanism deployed by NFS
administrators. As a result, NFS security remains in an
unsatisfactory state.
A deeper purpose of this document is to attempt to address some of
the shortcomings of AUTH_SYS so that, where it has been impractical
to deploy RPCSEC GSS, better NFSv4 security can nevertheless be
achieved.
When AUTH_SYS is used with TLS and no client certificate is
available, the RPC server is still acting on RPC requests for which
there is no trustworthy authentication. In-transit traffic is
protected, but the client itself can still misrepresent user identity
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without detection. This is an improvement from AUTH_SYS without
encryption, but it leaves a critical security exposure.
Therefore, the RECOMMENDED deployment mode is that clients have
certificate material configured and used so that servers can have a
degree of trust that clients are acting responsibly.
7.2. STRIPTLS Attacks
A classic form of attack on network protocols that initiate an
association in plain-text to discover support for TLS is a man-in-
the-middle that alters the plain-text handshake to make it appear as
though TLS support is not available on one or both peers. Clients
implementers can choose from the following to mitigate STRIPTLS
attacks:
o Clients can be configured to require TLS encryption. If an
attacker spoofs the handshake, the client disconnects and reports
the problem.
o A TLSA record [RFC6698] can alert clients that TLS is expected to
work, and provides a binding of hostname to x.509 identity. If
TLS cannot be negotiated or authentication fails, the client
disconnects and reports the problem.
8. IANA Considerations
In accordance with Section 6 of [RFC7301], the authors request that
IANA allocate the following value in the "Application-Layer Protocol
Negotiation (ALPN) Protocol IDs" registry. The "sunrpc" string
identifies SunRPC when used over TLS.
Protocol:
SunRPC
Identification Sequence:
0x73 0x75 0x6e 0x72 0x70 0x63 ("sunrpc")
Reference:
RFC-TBD
9. References
9.1. Normative References
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[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119,
DOI 10.17487/RFC2119, March 1997,
<https://www.rfc-editor.org/info/rfc2119>.
[RFC4279] Eronen, P., Ed. and H. Tschofenig, Ed., "Pre-Shared Key
Ciphersuites for Transport Layer Security (TLS)",
RFC 4279, DOI 10.17487/RFC4279, December 2005,
<https://www.rfc-editor.org/info/rfc4279>.
[RFC5280] Cooper, D., Santesson, S., Farrell, S., Boeyen, S.,
Housley, R., and W. Polk, "Internet X.509 Public Key
Infrastructure Certificate and Certificate Revocation List
(CRL) Profile", RFC 5280, DOI 10.17487/RFC5280, May 2008,
<https://www.rfc-editor.org/info/rfc5280>.
[RFC5531] Thurlow, R., "RPC: Remote Procedure Call Protocol
Specification Version 2", RFC 5531, DOI 10.17487/RFC5531,
May 2009, <https://www.rfc-editor.org/info/rfc5531>.
[RFC6125] Saint-Andre, P. and J. Hodges, "Representation and
Verification of Domain-Based Application Service Identity
within Internet Public Key Infrastructure Using X.509
(PKIX) Certificates in the Context of Transport Layer
Security (TLS)", RFC 6125, DOI 10.17487/RFC6125, March
2011, <https://www.rfc-editor.org/info/rfc6125>.
[RFC6347] Rescorla, E. and N. Modadugu, "Datagram Transport Layer
Security Version 1.2", RFC 6347, DOI 10.17487/RFC6347,
January 2012, <https://www.rfc-editor.org/info/rfc6347>.
[RFC7258] Farrell, S. and H. Tschofenig, "Pervasive Monitoring Is an
Attack", BCP 188, RFC 7258, DOI 10.17487/RFC7258, May
2014, <https://www.rfc-editor.org/info/rfc7258>.
[RFC7301] Friedl, S., Popov, A., Langley, A., and E. Stephan,
"Transport Layer Security (TLS) Application-Layer Protocol
Negotiation Extension", RFC 7301, DOI 10.17487/RFC7301,
July 2014, <https://www.rfc-editor.org/info/rfc7301>.
[RFC7861] Adamson, A. and N. Williams, "Remote Procedure Call (RPC)
Security Version 3", RFC 7861, DOI 10.17487/RFC7861,
November 2016, <https://www.rfc-editor.org/info/rfc7861>.
[RFC7942] Sheffer, Y. and A. Farrel, "Improving Awareness of Running
Code: The Implementation Status Section", BCP 205,
RFC 7942, DOI 10.17487/RFC7942, July 2016,
<https://www.rfc-editor.org/info/rfc7942>.
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[RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
May 2017, <https://www.rfc-editor.org/info/rfc8174>.
[RFC8446] Rescorla, E., "The Transport Layer Security (TLS) Protocol
Version 1.3", RFC 8446, DOI 10.17487/RFC8446, August 2018,
<https://www.rfc-editor.org/info/rfc8446>.
9.2. Informative References
[RFC1813] Callaghan, B., Pawlowski, B., and P. Staubach, "NFS
Version 3 Protocol Specification", RFC 1813,
DOI 10.17487/RFC1813, June 1995,
<https://www.rfc-editor.org/info/rfc1813>.
[RFC2203] Eisler, M., Chiu, A., and L. Ling, "RPCSEC_GSS Protocol
Specification", RFC 2203, DOI 10.17487/RFC2203, September
1997, <https://www.rfc-editor.org/info/rfc2203>.
[RFC2818] Rescorla, E., "HTTP Over TLS", RFC 2818,
DOI 10.17487/RFC2818, May 2000,
<https://www.rfc-editor.org/info/rfc2818>.
[RFC5661] Shepler, S., Ed., Eisler, M., Ed., and D. Noveck, Ed.,
"Network File System (NFS) Version 4 Minor Version 1
Protocol", RFC 5661, DOI 10.17487/RFC5661, January 2010,
<https://www.rfc-editor.org/info/rfc5661>.
[RFC6698] Hoffman, P. and J. Schlyter, "The DNS-Based Authentication
of Named Entities (DANE) Transport Layer Security (TLS)
Protocol: TLSA", RFC 6698, DOI 10.17487/RFC6698, August
2012, <https://www.rfc-editor.org/info/rfc6698>.
[RFC6973] Cooper, A., Tschofenig, H., Aboba, B., Peterson, J.,
Morris, J., Hansen, M., and R. Smith, "Privacy
Considerations for Internet Protocols", RFC 6973,
DOI 10.17487/RFC6973, July 2013,
<https://www.rfc-editor.org/info/rfc6973>.
[RFC7525] Sheffer, Y., Holz, R., and P. Saint-Andre,
"Recommendations for Secure Use of Transport Layer
Security (TLS) and Datagram Transport Layer Security
(DTLS)", BCP 195, RFC 7525, DOI 10.17487/RFC7525, May
2015, <https://www.rfc-editor.org/info/rfc7525>.
[RFC7530] Haynes, T., Ed. and D. Noveck, Ed., "Network File System
(NFS) Version 4 Protocol", RFC 7530, DOI 10.17487/RFC7530,
March 2015, <https://www.rfc-editor.org/info/rfc7530>.
Myklebust & Lever Expires October 17, 2019 [Page 15]
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[RFC7862] Haynes, T., "Network File System (NFS) Version 4 Minor
Version 2 Protocol", RFC 7862, DOI 10.17487/RFC7862,
November 2016, <https://www.rfc-editor.org/info/rfc7862>.
[RFC7863] Haynes, T., "Network File System (NFS) Version 4 Minor
Version 2 External Data Representation Standard (XDR)
Description", RFC 7863, DOI 10.17487/RFC7863, November
2016, <https://www.rfc-editor.org/info/rfc7863>.
[RFC8166] Lever, C., Ed., Simpson, W., and T. Talpey, "Remote Direct
Memory Access Transport for Remote Procedure Call Version
1", RFC 8166, DOI 10.17487/RFC8166, June 2017,
<https://www.rfc-editor.org/info/rfc8166>.
[RFC8471] Popov, A., Ed., Nystroem, M., Balfanz, D., and J. Hodges,
"The Token Binding Protocol Version 1.0", RFC 8471,
DOI 10.17487/RFC8471, October 2018,
<https://www.rfc-editor.org/info/rfc8471>.
9.3. URIs
[1] https://www.linuxjournal.com/content/encrypting-nfsv4-stunnel-tls
Acknowledgments
Special mention goes to Charles Fisher, author of "Encrypting NFSv4
with Stunnel TLS" [1]. His article inspired the mechanism described
in this document.
Many thanks to Tigran Mkrtchyan for his work on the DESY prototype
and resulting feedback to this document.
The authors are grateful to Bill Baker, David Black, Alan DeKok, Lars
Eggert, Benjamin Kaduk, Olga Kornievskaia, Greg Marsden, Alex
McDonald, David Noveck, Justin Mazzola Paluska, Tom Talpey, and
Martin Thomson for their input and support of this work.
Lastly, special thanks go to Transport Area Director Magnus
Westerlund, NFSV4 Working Group Chairs Spencer Shepler and Brian
Pawlowski, and NFSV4 Working Group Secretary Thomas Haynes for their
guidance and oversight.
Authors' Addresses
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Internet-Draft RPC-Over-TLS April 2019
Trond Myklebust
Hammerspace Inc
4300 El Camino Real Ste 105
Los Altos, CA 94022
United States of America
Email: trond.myklebust@hammerspace.com
Charles Lever (editor)
Oracle Corporation
United States of America
Email: chuck.lever@oracle.com
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