rfc9289.original.xml   rfc9289.xml 
<?xml version='1.0' encoding='utf-8'?> <?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE rfc SYSTEM "rfc2629-xhtml.ent">
<?xml-stylesheet type="text/xsl" href="rfc2629.xslt"?>
<rfc <!DOCTYPE rfc [
category="std" <!ENTITY nbsp "&#160;">
docName="draft-ietf-nfsv4-rpc-tls-11" <!ENTITY zwsp "&#8203;">
ipr="trust200902" <!ENTITY nbhy "&#8209;">
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scripts="Common,Latin" ]>
sortRefs="true"
submissionType="IETF" <rfc xmlns:xi="http://www.w3.org/2001/XInclude" consensus="true"
symRefs="true" category="std" ipr="trust200902" docName="draft-ietf-nfsv4-rpc-tls-11" numb
tocDepth="3" er="9289"
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updates="5531" tocInclude="true" tocDepth="4" symRefs="true" sortRefs="true"
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xml:lang="en">
<front> <front>
<title abbrev="RPC-Over-TLS"> <title abbrev="RPC-With-TLS">
Towards Remote Procedure Call Encryption By Default Towards Remote Procedure Call Encryption by Default
</title> </title>
<seriesInfo name="Internet-Draft" value="draft-ietf-nfsv4-rpc-tls-11"/> <seriesInfo name="RFC" value="9289"/>
<author initials="T." surname="Myklebust" fullname="Trond Myklebust"> <author initials="T." surname="Myklebust" fullname="Trond Myklebust">
<organization abbrev="Hammerspace" showOnFrontPage="true"> <organization abbrev="Hammerspace" showOnFrontPage="true">
Hammerspace Inc Hammerspace Inc.
</organization> </organization>
<address> <address>
<postal> <postal>
<street>4300 El Camino Real Ste 105</street> <street>4300 El Camino Real, Suite 105</street>
<city>Los Altos</city> <city>Los Altos</city>
<region>CA</region> <region>CA</region>
<code>94022</code> <code>94022</code>
<country>United States of America</country> <country>United States of America</country>
</postal> </postal>
<email>trond.myklebust@hammerspace.com</email> <email>trond.myklebust@hammerspace.com</email>
</address> </address>
</author> </author>
<author initials="C." surname="Lever" fullname="Charles Lever" role="editor"> <author initials="C." surname="Lever" fullname="Charles Lever" role="editor">
skipping to change at line 60 skipping to change at line 56
<street/> <street/>
<city/> <city/>
<region/> <region/>
<code/> <code/>
<country>United States of America</country> <country>United States of America</country>
</postal> </postal>
<email>chuck.lever@oracle.com</email> <email>chuck.lever@oracle.com</email>
</address> </address>
</author> </author>
<date/> <date year="2022" month="September" />
<area>Transport</area> <area>Transport</area>
<workgroup>Network File System Version 4</workgroup> <workgroup>Network File System Version 4</workgroup>
<keyword>network file system</keyword>
<keyword>remote procedure call</keyword>
<keyword>transport layer security</keyword>
<keyword>X.509</keyword>
<abstract> <abstract>
<t> <t>
This document describes a mechanism that, This document describes a mechanism that, through the use of opportunistic
through the use of opportunistic Transport Layer Security (TLS), Transport Layer Security (TLS), enables encryption of Remote Procedure Call
enables encryption of Remote Procedure Call (RPC) transactions (RPC) transactions while they are in transit. The proposed mechanism
while they are in-transit. interoperates with Open Network Computing (ONC) RPC implementations that do
The proposed mechanism interoperates with ONC RPC implementations not support it. This document updates RFC 5531.
that do not support it.
This document updates RFC 5531.
</t> </t>
</abstract> </abstract>
<note removeInRFC="true">
<t>
Discussion of this draft takes place
on the NFSv4 working group mailing list (nfsv4@ietf.org),
which is archived at
<eref target="https://mailarchive.ietf.org/arch/browse/nfsv4/"/>.
Working Group information can be found at
<eref target="https://datatracker.ietf.org/wg/nfsv4/about/"/>.
</t>
<t>
The source for this draft is maintained in GitHub.
Suggested changes should be submitted as pull requests at
<eref target="https://github.com/chucklever/i-d-rpc-tls"/>.
Instructions are on that page as well.
</t>
</note>
</front> </front>
<middle> <middle>
<section <section
anchor="section_8F035331-8EB8-4FBC-973A-673FBA5FE952" anchor="section_8F035331-8EB8-4FBC-973A-673FBA5FE952"
numbered="true" numbered="true"
removeInRFC="false" removeInRFC="false"
toc="default"> toc="default">
<name>Introduction</name> <name>Introduction</name>
<t> <t>
In 2014 the IETF published In 2014 the IETF published a document entitled "Pervasive Monitoring Is an
a document entitled "Pervasive Monitoring Is an Attack" Attack" <xref target="RFC7258" format="default" />, which
<xref target="RFC7258" format="default" sectionFormat="of"/>, recognized that unauthorized observation of network traffic had become
which recognized that unauthorized observation widespread and was a subversive threat to all who make use of the Internet at
of network traffic had become widespread large. It strongly recommended that newly defined Internet protocols should
and make a genuine effort to mitigate monitoring attacks. Typically, this
was a subversive threat mitigation includes encrypting data in transit.
to all who make use of the Internet at large.
It strongly recommended that newly defined Internet protocols
should make a genuine effort to mitigate monitoring attacks.
Typically this mitigation includes encrypting data in transit.
</t> </t>
<t> <t>
The Remote Procedure Call version 2 protocol The Remote Procedure Call version 2 protocol has been a Proposed Standard for
has been a Proposed Standard for three decades three decades (see
(see <xref target="RFC5531" format="default" />
<xref target="RFC5531" format="default" sectionFormat="of"/> and its antecedents). Over twenty years ago, Eisler et al. first introduced
and its antecedents). RPCSEC_GSS as an in-transit encryption mechanism for RPC <xref
Over twenty years ago, target="RFC2203" format="default" />. However, experience
Eisler et al. first introduced RPCSEC GSS has shown that RPCSEC_GSS with in-transit encryption can be challenging to use
as an in-transit encryption mechanism for RPC in practice due to the following:
<xref target="RFC2203" format="default" sectionFormat="of"/>.
However, experience has shown
that RPCSEC GSS with in-transit encryption
can be challenging to use in practice:
</t> </t>
<ul spacing="normal" bare="false" empty="false">
<ul spacing="normal">
<li> <li>
Parts of each RPC header remain in clear-text, Parts of each RPC header remain in cleartext,
constituting a loss of metadata confidentiality. constituting a loss of metadata confidentiality.
</li> </li>
<li> <li>
Offloading the GSS privacy service is not practical Offloading the Generic Security Service (GSS) privacy service is not practical
in large multi-user deployments in large multi-user deployments
since each message is encrypted using a key based since each message is encrypted using a key based
on the issuing RPC user. on the issuing RPC user.
</li> </li>
</ul> </ul>
<t> <t>
However strong GSS-provided confidentiality is, However strong GSS-provided confidentiality is,
it cannot provide any security if the challenges it cannot provide any security if the challenges
of using it result in choosing not to deploy it at all. of using it result in choosing not to deploy it at all.
</t> </t>
<t> <t>
Moreover, the use of AUTH_SYS Moreover, the use of AUTH_SYS
remains common despite the adverse effects remains common despite the adverse effects
that acceptance of UIDs and GIDs that acceptance of User Identifiers (UIDs) and Group Identifiers (GIDs)
from unauthenticated clients brings with it. from unauthenticated clients brings with it.
Continued use is in part because: Continued use is in part because:
</t> </t>
<ul spacing="normal" bare="false" empty="false"> <ul spacing="normal">
<li> <li>
Per-client deployment and administrative costs Per-client deployment and administrative costs
for the only well-defined alternative to AUTH_SYS for the only well-defined alternative to AUTH_SYS
are expensive at scale. are expensive at scale.
For instance, administrators must provide keying material For instance, administrators must provide keying material
for each RPC client, including transient clients. for each RPC client, including transient clients.
</li> </li>
<li> <li>
GSS host identity management and user identity management GSS host identity management and user identity management typically must be
typically must be enforced in the same security realm. enforced in the same security realm. However, cloud providers, for instance,
However, cloud providers, for instance, might prefer might prefer to remain authoritative for host identity but allow tenants to
to remain authoritative for host identity manage user identities within their private networks.
but
allow tenants to manage user identities within their private networks.
</li> </li>
</ul> </ul>
<t> <t>
In view of the challenges with the In view of the challenges with the currently available mechanisms for
currently available mechanisms authenticating and protecting the confidentiality of RPC transactions, this
for document specifies a transport-layer security mechanism that complements the
authenticating existing ones. The TLS <xref target="RFC8446"
and format="default"/> and Datagram Transport Layer Security (DTLS)
protecting the confidentiality <xref target="RFC9147" format="default" />
of RPC transactions, protocols are well-established Internet building blocks that protect many
this document specifies a transport-layer security mechanism standard Internet protocols such as the Hypertext Transfer Protocol (HTTP)
that complements the existing ones. <xref target="RFC9110" format="default" />.
The
Transport Layer Security
<xref target="RFC8446" format="default" sectionFormat="of"/>
(TLS)
and
Datagram Transport Layer Security
<xref target="I-D.ietf-tls-dtls13" format="default" sectionFormat="of"/>
(DTLS)
protocols are a well-established Internet building blocks
that protect many standard Internet protocols
such as the Hypertext Transport Protocol (HTTP)
<xref target="RFC2818" format="default" sectionFormat="of"/>.
</t> </t>
<t> <t>
Encrypting at the RPC transport layer accords several significant benefits: Encrypting at the RPC transport layer accords several significant benefits:
</t> </t>
<dl newline="false" spacing="normal"> <dl spacing="normal">
<dt>Encryption By Default:</dt> <dt>Encryption by Default:</dt>
<dd> <dd>
Transport encryption can be enabled Transport encryption can be enabled
without additional administrative tasks such as without additional administrative tasks such as
identifying client systems to a trust authority identifying client systems to a trust authority
and and
providing each with keying material. providing each with keying material.
</dd> </dd>
<dt>Encryption Offload:</dt> <dt>Encryption Offload:</dt>
<dd> <dd>
Hardware support for the GSS privacy service has not appeared in the marketplace . Hardware support for the GSS privacy service has not appeared in the marketplace .
skipping to change at line 237 skipping to change at line 200
</dd> </dd>
<dt>Compatibility:</dt> <dt>Compatibility:</dt>
<dd> <dd>
The imposition of encryption at the transport layer The imposition of encryption at the transport layer
protects any upper-layer protocol that employs RPC, protects any upper-layer protocol that employs RPC,
without alteration of the upper-layer protocol. without alteration of the upper-layer protocol.
</dd> </dd>
</dl> </dl>
<t> <t>
Further, Further,
<xref target="section_2AE49383-E6B2-4830-8407-995FEBF727F2" format="default" sec tionFormat="of"/> <xref target="section_2AE49383-E6B2-4830-8407-995FEBF727F2" format="default" />
of the current document defines policies in line with of the current document defines policies in line with
<xref target="RFC7435" format="default" sectionFormat="of"/> <xref target="RFC7435" format="default" />
which enable RPC-over-TLS to be deployed opportunistically that enable RPC-with-TLS to be deployed opportunistically in environments that
in environments that contain RPC implementations that do not support TLS. contain RPC implementations that do not support TLS. However, specifications
However, specifications for RPC-based upper-layer protocols for RPC-based upper-layer protocols should choose to require even stricter
should choose to require even stricter policies that guarantee policies that guarantee encryption and host authentication are used for all RPC
encryption transactions to mitigate against pervasive monitoring attacks <xref
and target="RFC7258" format="default" />. Enforcing the use of
host authentication RPC-with-TLS is of particular importance for existing upper-layer protocols
is used for all RPC transactions whose security infrastructure is weak.
to mitigate against pervasive monitoring attacks
<xref target="RFC7258" format="default" sectionFormat="of"/>.
Enforcing the use of RPC-over-TLS is of particular importance
for existing upper-layer protocols whose security infrastructure is weak.
</t> </t>
<t> <t>
The protocol specification in the current document assumes The protocol specification in the current document assumes that support for
that support for ONC RPC <xref target="RFC5531" format="default"/>, TLS
ONC RPC <xref target="RFC8446" format="default" />, PKIX <xref
<xref target="RFC5531" format="default" sectionFormat="of"/>, target="RFC5280" format="default" />, DNSSEC/DNS-Based
TLS Authentication of Named Entities (DANE) <xref target="RFC6698"
<xref target="RFC8446" format="default" sectionFormat="of"/>, format="default" />, and optionally RPCSEC_GSS
PKIX <xref target="RFC2203" format="default" />
<xref target="RFC5280" format="default" sectionFormat="of"/>,
DNSSEC/DANE
<xref target="RFC6698" format="default" sectionFormat="of"/>,
and optionally
RPCSEC_GSS
<xref target="RFC2203" format="default" sectionFormat="of"/>
is available within the platform is available within the platform
where RPC-over-TLS support is to be added. where RPC-with-TLS support is to be added.
</t> </t>
</section> </section>
<section <section
anchor="section_024237C9-5504-49B4-A2D3-2D2A5EFBB967" anchor="section_024237C9-5504-49B4-A2D3-2D2A5EFBB967"
numbered="true" numbered="true"
removeInRFC="false" removeInRFC="false"
toc="default"> toc="default">
<name>Requirements Language</name> <name>Requirements Language</name>
<t> <t>
The key words "<bcp14>MUST</bcp14>", "<bcp14>MUST NOT</bcp14>", The key words "<bcp14>MUST</bcp14>", "<bcp14>MUST NOT</bcp14>",
"<bcp14>REQUIRED</bcp14>", "<bcp14>SHALL</bcp14>", "<bcp14>REQUIRED</bcp14>", "<bcp14>SHALL</bcp14>", "<bcp14>SHALL NOT</bcp14>",
"<bcp14>SHALL NOT</bcp14>", "<bcp14>SHOULD</bcp14>", "<bcp14>SHOULD</bcp14>", "<bcp14>SHOULD NOT</bcp14>",
"<bcp14>SHOULD NOT</bcp14>",
"<bcp14>RECOMMENDED</bcp14>", "<bcp14>NOT RECOMMENDED</bcp14>", "<bcp14>RECOMMENDED</bcp14>", "<bcp14>NOT RECOMMENDED</bcp14>",
"<bcp14>MAY</bcp14>", and "<bcp14>OPTIONAL</bcp14>" "<bcp14>MAY</bcp14>", and "<bcp14>OPTIONAL</bcp14>" in this document are to be
in this document are to be interpreted interpreted as described in BCP&nbsp;14
as described in BCP&nbsp;14 <xref target="RFC2119" format="default" />
<xref target="RFC2119" format="default" sectionFormat="of"/> <xref target="RFC8174" format="default" />
<xref target="RFC8174" format="default" sectionFormat="of"/>
when, and only when, they appear in all capitals, as shown here. when, and only when, they appear in all capitals, as shown here.
</t> </t>
</section> </section>
<section <section
anchor="section_0EB1100E-DAA8-4B2C-98AE-94258CFDCB1B" anchor="section_0EB1100E-DAA8-4B2C-98AE-94258CFDCB1B"
numbered="true" numbered="true"
removeInRFC="false" removeInRFC="false"
toc="default"> toc="default">
<name>Terminology</name> <name>Terminology</name>
<t> <t>
This document adopts the terminology introduced in This document adopts the terminology introduced in
<xref target="RFC6973" section="3" format="default" sectionFormat="of"/> <xref target="RFC6973" section="3" format="default" sectionFormat="of"/>
and assumes a working knowledge of and assumes a working knowledge of
the Remote Procedure Call (RPC) version 2 protocol the RPC version 2 protocol
<xref target="RFC5531" format="default" sectionFormat="of"/> <xref target="RFC5531" format="default" />
and and
the Transport Layer Security (TLS) version 1.3 protocol the TLS version 1.3 protocol
<xref target="RFC8446" format="default" sectionFormat="of"/>. <xref target="RFC8446" format="default" />.
</t> </t>
<t> <t>
Note also that the NFS community long ago adopted the Note also that the NFS community long ago adopted the
use of the term "privacy" from documents such as use of the term "privacy" from documents such as
<xref target="RFC2203" format="default" sectionFormat="of"/>. <xref target="RFC2203" format="default" />.
In the current document, the authors use the term In the current document, the authors use the term
"privacy" only when referring specifically "privacy" only when referring specifically
to the historic GSS privacy service defined in to the historic GSS privacy service defined in
<xref target="RFC2203" format="default" sectionFormat="of"/>. <xref target="RFC2203" format="default" />.
Otherwise, the authors use the term "confidentiality", Otherwise, the authors use the term "confidentiality",
following the practices of contemporary security communities. following the practices of contemporary security communities.
</t> </t>
<t> <t>
We adhere to the convention that a "client" We adhere to the convention that a "client"
is a network host that actively initiates an association, is a network host that actively initiates an association,
and and
a "server" is a network host that passively accepts an association request. a "server" is a network host that passively accepts an association request.
</t> </t>
<t> <t>
RPC documentation historically refers to RPC documentation historically refers to
the authentication of a connecting host as "machine authentication" the authentication of a connecting host as "machine authentication"
or "host authentication". or "host authentication".
TLS documentation refers to the same as "peer authentication". TLS documentation refers to the same as "peer authentication".
In the current document there is little distinction between these terms. In the current document, there is little distinction between these terms.
</t> </t>
<t> <t>
The term "user authentication" in the current document refers specifically The term "user authentication" in the current document refers specifically to
to the RPC caller's credential, provided in the the RPC caller's credential, provided in the "cred" and "verf" fields in each
"cred" RPC Call.
and
"verf"
fields in each RPC Call.
</t> </t>
</section> </section>
<section <section
anchor="section_EC3FEED5-1DE0-454B-9AB3-CE47BA901583" anchor="section_EC3FEED5-1DE0-454B-9AB3-CE47BA901583"
numbered="true" numbered="true"
removeInRFC="false" removeInRFC="false"
toc="default"> toc="default">
<name>RPC-Over-TLS in Operation</name> <name>RPC-with-TLS in Operation</name>
<section <section
anchor="section_0A03673B-14BA-4228-8A8A-F76AA318CA73" anchor="section_0A03673B-14BA-4228-8A8A-F76AA318CA73"
numbered="true" numbered="true"
removeInRFC="false" removeInRFC="false"
toc="default"> toc="default">
<name>Discovering Server-side TLS Support</name> <name>Discovering Server-Side TLS Support</name>
<t> <t>
The mechanism described in the current document The mechanism described in the current document
interoperates fully with RPC implementations interoperates fully with RPC implementations
that do not support RPC-over-TLS. that do not support RPC-with-TLS.
When an RPC-over-TLS-enabled peer encounters a peer that When an RPC-with-TLS-enabled peer encounters a peer that
does not support RPC-over-TLS, does not support RPC-with-TLS,
policy settings on the RPC-over-TLS-enabled peer determine policy settings on the RPC-with-TLS-enabled peer determine
whether RPC operation continues without the use of TLS, whether RPC operation continues without the use of TLS
or RPC operation is not permitted. or is discontinued altogether.
</t> </t>
<t> <t>
To achieve this interoperability, To achieve this interoperability,
we introduce a new RPC authentication flavor called AUTH_TLS. we introduce a new RPC authentication flavor called AUTH_TLS.
The AUTH_TLS authentication flavor signals that the client wants The AUTH_TLS authentication flavor signals that the client wants
to initiate TLS negotiation if the server supports it. to initiate TLS negotiation if the server supports it.
Except for the modifications described in this section, Except for the modifications described in this section,
the RPC protocol is unaware of security encapsulation the RPC protocol is unaware of security encapsulation
at the transport layer. at the transport layer.
The value of AUTH_TLS is defined in The value of AUTH_TLS is defined in
<xref target="section_2CD51855-CE40-4B8D-A220-F211C477964F" format="default" sec tionFormat="of"/>. <xref target="section_2CD51855-CE40-4B8D-A220-F211C477964F" format="default" />.
</t> </t>
<t> <t>
An RPC client begins its communication with an RPC server An RPC client begins its communication with an RPC server
by selecting a transport and destination port. by selecting a transport and destination port.
The choice of transport and port is The choice of transport and port is
typically based on the RPC program that is to be used. typically based on the RPC program that is to be used.
The RPC client might query the RPC server's RPCBIND service The RPC client might query the RPC server's RPCBIND service
to make this selection to make this selection
(The RPCBIND service is described in (The RPCBIND service is described in
<xref target="RFC1833" format="default" sectionFormat="of"/>). <xref target="RFC1833" format="default" />).
The mechanism described in the current document The mechanism described in the current document
does not support RPC transports other than TCP and UDP. does not support RPC transports other than TCP and UDP.
In all cases, an RPC server <bcp14>MUST</bcp14> listen on the same ports In all cases, an RPC server <bcp14>MUST</bcp14> listen on the same ports
for (D)TLS-protected RPC programs for (D)TLS-protected RPC programs
as the ports used when (D)TLS is not available. as the ports used when (D)TLS is not available.
</t> </t>
<t> <t>
To protect RPC traffic to a TCP port, To protect RPC traffic to a TCP port,
the RPC client opens a TCP connection to that port the RPC client opens a TCP connection to that port
and sends a NULL RPC procedure and sends a NULL RPC procedure
with an auth_flavor of AUTH_TLS on that connection. with an auth_flavor of AUTH_TLS on that connection.
To protect RPC traffic to a UDP port, To protect RPC traffic to a UDP port,
the RPC client sends a UDP datagram to that port the RPC client sends a UDP datagram to that port
containing a NULL RPC procedure with an auth_flavor of AUTH_TLS. containing a NULL RPC procedure with an auth_flavor of AUTH_TLS.
The client constructs this RPC procedure as follows: The client constructs this RPC procedure as follows:
</t> </t>
<ul spacing="normal" bare="false" empty="false"> <ul spacing="normal">
<li> <li>
The length of the opaque data constituting the credential The length of the opaque data constituting the credential
sent in the RPC Call message <bcp14>MUST</bcp14> be zero. sent in the RPC Call message <bcp14>MUST</bcp14> be zero.
</li> </li>
<li> <li>
The verifier accompanying the credential <bcp14>MUST</bcp14> be an AUTH_NONE The verifier accompanying the credential <bcp14>MUST</bcp14> be an AUTH_NONE
verifier of length zero. verifier of length zero.
</li> </li>
<li> <li>
The flavor value of the verifier in the RPC Reply message The flavor value of the verifier in the RPC Reply message
skipping to change at line 424 skipping to change at line 374
</li> </li>
<li> <li>
The length of the verifier's body field is eight. The length of the verifier's body field is eight.
</li> </li>
<li> <li>
The bytes of the verifier's body field encode the ASCII characters The bytes of the verifier's body field encode the ASCII characters
"STARTTLS" as a fixed-length opaque. "STARTTLS" as a fixed-length opaque.
</li> </li>
</ul> </ul>
<t> <t>
The RPC server signals its corresponding support for RPC-over-TLS The RPC server signals its corresponding support for RPC-with-TLS
by replying with by replying with
a reply_stat of MSG_ACCEPTED a reply_stat of MSG_ACCEPTED
and and
an AUTH_NONE verifier containing the "STARTTLS" token. an AUTH_NONE verifier containing the "STARTTLS" token.
The client <bcp14>SHOULD</bcp14> proceed with TLS session establishment, The client <bcp14>SHOULD</bcp14> proceed with TLS session establishment,
even if the Reply's accept_stat is not SUCCESS. even if the Reply's accept_stat is not SUCCESS.
If the AUTH_TLS probe was done via TCP, If the AUTH_TLS probe was done via TCP,
the RPC client <bcp14>MUST</bcp14> send the "ClientHello" message the RPC client <bcp14>MUST</bcp14> send the "ClientHello" message
on the same connection. on the same connection.
If the AUTH_TLS probe was done via UDP, If the AUTH_TLS probe was done via UDP,
skipping to change at line 475 skipping to change at line 425
the RPC server <bcp14>MUST</bcp14> reject that RPC Call the RPC server <bcp14>MUST</bcp14> reject that RPC Call
by returning a reply_stat of MSG_DENIED by returning a reply_stat of MSG_DENIED
with a reject_stat of AUTH_ERROR with a reject_stat of AUTH_ERROR
and an auth_stat of AUTH_BADCRED. and an auth_stat of AUTH_BADCRED.
</t> </t>
<t> <t>
Once the TLS session handshake is complete, Once the TLS session handshake is complete,
the RPC client and server have established the RPC client and server have established
a secure channel for exchanging RPC transactions. a secure channel for exchanging RPC transactions.
A successful AUTH_TLS probe on one particular port/transport tuple A successful AUTH_TLS probe on one particular port/transport tuple
does not imply that RPC-over-TLS is available on that same server does not imply that RPC-with-TLS is available on that same server
using a different port/transport tuple, using a different port/transport tuple,
nor does it imply that nor does it imply that
RPC-over-TLS will be available in the future RPC-with-TLS will be available in the future
using the successfully probed port. using the successfully probed port.
</t> </t>
</section> </section>
<section <section
anchor="section_6EDEF553-C95A-47D7-ABBA-0B537FE3A959" anchor="section_6EDEF553-C95A-47D7-ABBA-0B537FE3A959"
numbered="true" numbered="true"
removeInRFC="false" removeInRFC="false"
toc="default"> toc="default">
<name>Authentication</name> <name>Authentication</name>
skipping to change at line 489 skipping to change at line 439
using the successfully probed port. using the successfully probed port.
</t> </t>
</section> </section>
<section <section
anchor="section_6EDEF553-C95A-47D7-ABBA-0B537FE3A959" anchor="section_6EDEF553-C95A-47D7-ABBA-0B537FE3A959"
numbered="true" numbered="true"
removeInRFC="false" removeInRFC="false"
toc="default"> toc="default">
<name>Authentication</name> <name>Authentication</name>
<t> <t>
There is some overlap between the authentication There is some overlap between the authentication
capabilities of RPC and TLS. capabilities of RPC and TLS.
The goal of interoperability with implementations The goal of interoperability with implementations
that do not support TLS requires that do not support TLS requires
limiting the combinations that are allowed limiting the combinations that are allowed
and and
precisely specifying the role that each layer plays. precisely specifying the role that each layer plays.
</t> </t>
<t> <t>
Each RPC server that supports RPC-over-TLS <bcp14>MUST</bcp14> possess a unique global identity Each RPC server that supports RPC-with-TLS <bcp14>MUST</bcp14> possess a unique global identity
(e.g., a certificate that is signed by a well-known trust anchor). (e.g., a certificate that is signed by a well-known trust anchor).
Such an RPC server <bcp14>MUST</bcp14> request a TLS peer identity from each cli ent Such an RPC server <bcp14>MUST</bcp14> request a TLS peer identity from each cli ent
upon first contact. upon first contact.
There are two different modes of client deployment: There are two different modes of client deployment:
</t> </t>
<dl newline="true" spacing="normal"> <dl newline="true" spacing="normal">
<dt>Server-only Host Authentication</dt> <dt>Server-Only Host Authentication</dt>
<dd> <dd>
In this type of deployment, In this type of deployment,
the client can authenticate the server host the client can authenticate the server host
using the presented server peer TLS identity, using the presented server peer TLS identity,
but the server cannot authenticate the client. but the server cannot authenticate the client.
In this situation, In this situation,
RPC-over-TLS clients are anonymous. RPC-with-TLS clients are anonymous.
They present no globally unique identifier to the server peer. They present no globally unique identifier to the server peer.
</dd> </dd>
<dt>Mutual Host Authentication</dt> <dt>Mutual Host Authentication</dt>
<dd> <dd>
In this type of deployment, In this type of deployment, the client possesses an identity that is backed by
the client possesses an identity that is backed by a trusted entity a trusted entity (e.g., a pre-shared key or a certificate validated with a
(e.g. a pre-shared key or a certificate validated with a certification path). certification path). As part of the TLS handshake, both peers authenticate
As part of the TLS handshake, both peers authenticate using the presented TLS id using the presented TLS identities. If authentication of either peer fails,
entities. or if authorization based on those identities blocks access to the server, the
If authentication of either peer fails, peers <bcp14>MUST</bcp14> reject the association. Further explanation appears in
or <xref target="section_936921ED-67BB-46BF-B316-6740E07F6652"/>.
if authorization based on those identities blocks access to the server,
the peers <bcp14>MUST</bcp14> reject the association.
Further explanation appears in
<xref target="section_936921ED-67BB-46BF-B316-6740E07F6652" format="default" sec
tionFormat="of"/>.
</dd> </dd>
</dl> </dl>
<t> <t>
In either of these modes, RPC user authentication is not affected In either of these modes, RPC user authentication is not affected by the use
by the use of transport layer security. of transport layer security. When a client presents a TLS peer identity to an
When a client presents a TLS peer identity to an RPC server, RPC server, the protocol extension described in the current document provides
the protocol extension described in the current document no way for the server to know whether that identity represents one RPC user on
provides no way for the server to know that client or is shared amongst many RPC users. Therefore, a server
whether that identity represents one RPC user on that client, implementation cannot utilize the remote TLS peer identity to authenticate RPC
or users.
is shared amongst many RPC users.
Therefore, a server implementation cannot utilize
the remote TLS peer identity to authenticate RPC users.
</t> </t>
<section <section
anchor="section_12D92596-F310-48C8-A4E0-B6CA038524E5" anchor="section_12D92596-F310-48C8-A4E0-B6CA038524E5"
numbered="true" numbered="true"
removeInRFC="false" removeInRFC="false"
toc="default"> toc="default">
<name>Using TLS with RPCSEC GSS</name> <name>Using TLS with RPCSEC_GSS</name>
<t> <t>
To use GSS, an RPC server has to possess a GSS service principal. To use GSS, an RPC server has to possess a GSS service principal.
On a TLS session, GSS mutual (peer) authentication occurs as usual, On a TLS session, GSS mutual (peer) authentication occurs as usual,
but only after a TLS session has been established for communication. but only after a TLS session has been established for communication.
Authentication of RPCSEC GSS users is unchanged by the use of TLS. Authentication of RPCSEC_GSS users is unchanged by the use of TLS.
</t> </t>
<t> <t>
RPCSEC GSS can also perform RPCSEC_GSS can also perform per-request integrity or confidentiality
per-request integrity or confidentiality protection. protection. When operating over a TLS session, these GSS services become
When operating over a TLS session, largely redundant. An RPC implementation capable of concurrently using TLS
these GSS services become largely redundant. and RPCSEC_GSS <bcp14>MUST</bcp14> use Generic Security Service Application
An RPC implementation capable of concurrently using TLS and RPCSEC GSS Program Interface (GSS-API) channel binding, as defined in <xref
<bcp14>MUST</bcp14> target="RFC5056" format="default" />, to determine when an
use GSS-API channel binding, as defined in underlying transport provides a sufficient degree of confidentiality.
<xref target="RFC5056" format="default" sectionFormat="of"/>, RPC-with-TLS implementations <bcp14>MUST</bcp14> provide the "tls-exporter"
to determine when an underlying transport channel binding type, as defined in <xref target="RFC9266" format="default" />.
provides a sufficient degree of confidentiality.
RPC-over-TLS implementations
<bcp14>MUST</bcp14>
provide the "tls-exporter" channel binding type, as defined in
<xref target="I-D.ietf-kitten-tls-channel-bindings-for-tls13" format="default" s
ectionFormat="of"/>.
</t> </t>
</section> </section>
</section> </section>
</section> </section>
<section <section
anchor="section_D93526DA-7B9D-419B-BE84-4AD8DA48577E" anchor="section_D93526DA-7B9D-419B-BE84-4AD8DA48577E"
numbered="true" numbered="true"
removeInRFC="false" removeInRFC="false"
toc="default"> toc="default">
<name>TLS Requirements</name> <name>TLS Requirements</name>
<t> <t>
When peers negotiate a TLS session that is to transport RPC, When peers negotiate a TLS session that is to transport RPC,
the following restrictions apply: the following restrictions apply:
</t> </t>
<ul spacing="normal" bare="false" empty="false"> <ul spacing="normal">
<li> <li>
Implementations <bcp14>MUST NOT</bcp14> negotiate TLS versions prior to v1.3 Implementations <bcp14>MUST NOT</bcp14> negotiate TLS versions prior to 1.3
(for TLS (for TLS
<xref target="RFC8446" format="default" sectionFormat="of"/> <xref target="RFC8446" format="default" />
or DTLS or DTLS <xref target="RFC9147" format="default" />,
<xref target="I-D.ietf-tls-dtls13" format="default" sectionFormat="of"/> respectively). Support for mandatory-to-implement cipher suites for the
respectively). negotiated TLS version is <bcp14>REQUIRED</bcp14>.
Support for mandatory-to-implement ciphersuites
for the negotiated TLS version is <bcp14>REQUIRED</bcp14>.
</li> </li>
<li> <li>
Implementations Implementations <bcp14>MUST</bcp14> conform to the recommendations for TLS
<bcp14>MUST</bcp14> usage specified in BCP 195 <xref target="RFC7525" format="default" />.
conform to the recommendations for TLS usage specified in BCP 195 Although RFC 7525 permits the use of TLS 1.2, the
<xref target="RFC7525" format="default" sectionFormat="of"/>. requirement to use TLS 1.3 or later for RPC-with-TLS takes precedence.
Although RFC 7525 permits the use of TLS v1.2, Further, because TLS 1.3 ciphers are qualitatively different than cipher
the requirement to use TLS v1.3 or later for RPC-over-TLS takes precedence. suites in previous versions of TLS, and RFC 7525 predates TLS 1.3, the cipher
Further, because TLS v1.3 ciphers suite recommendations in RFC 7525 do not apply to RPC-with-(D)TLS. A strict
are qualitatively different than cipher suites in previous versions of TLS TLS mode for RPC-with-TLS that protects against STRIPTLS attacks is discussed
and RFC 7525 predates TLS v1.3, in detail in <xref target="section_8894BDD2-0E0B-47A3-A2CB-70E4D93B55B0"
the cipher suite recommendations in RFC 7525 do not apply to RPC-over-(D)TLS. format="default" />.
A strict TLS mode for RPC-over-TLS that protects against STRIPTLS attacks
is discussed in detail in
<xref target="section_8894BDD2-0E0B-47A3-A2CB-70E4D93B55B0" format="default" sec
tionFormat="of"/>.
</li> </li>
<li> <li>
Implementations <bcp14>MUST</bcp14> support Implementations <bcp14>MUST</bcp14> support certificate-based mutual
certificate-based mutual authentication. authentication. Support for Pre-Shared Key (PSK) mutual authentication is
Support for PSK mutual authentication <bcp14>OPTIONAL</bcp14>; see
is <bcp14>OPTIONAL</bcp14>; <xref target="section_6DA9ED5F-BAD9-4126-95B7-E2331655A01E" format="default" />
see
<xref target="section_6DA9ED5F-BAD9-4126-95B7-E2331655A01E" format="default" sec
tionFormat="of"/>
for further details. for further details.
</li> </li>
<li> <li>
Negotiation of a ciphersuite providing confidentiality as Negotiation of a cipher suite providing confidentiality as
well as integrity protection is <bcp14>REQUIRED</bcp14>. well as integrity protection is <bcp14>REQUIRED</bcp14>.
</li> </li>
</ul> </ul>
<t> <t>
Client implementations <bcp14>MUST</bcp14> include the Client implementations <bcp14>MUST</bcp14> include the
"application_layer_protocol_negotiation(16)" extension "application_layer_protocol_negotiation(16)" extension
<xref target="RFC7301" format="default" sectionFormat="of"/> <xref target="RFC7301" format="default" />
in their "ClientHello" message in their "ClientHello" message
and <bcp14>MUST</bcp14> include the protocol identifier and <bcp14>MUST</bcp14> include the protocol identifier
defined in defined in
<xref target="section_58905D7A-06B1-4469-964A-DAC607DAC500" format="default" sec tionFormat="of"/> <xref target="section_58905D7A-06B1-4469-964A-DAC607DAC500" format="default" />
in that message's ProtocolNameList value. in that message's ProtocolNameList value.
</t> </t>
<t> <t>
Similarly, in response to the "ClientHello" message, Similarly, in response to the "ClientHello" message,
server implementations <bcp14>MUST</bcp14> include the server implementations <bcp14>MUST</bcp14> include the
"application_layer_protocol_negotiation(16)" extension "application_layer_protocol_negotiation(16)" extension
<xref target="RFC7301" format="default" sectionFormat="of"/> <xref target="RFC7301" format="default" />
in their "ServerHello" message in their "ServerHello" message
and <bcp14>MUST</bcp14> include only the protocol identifier and <bcp14>MUST</bcp14> include only the protocol identifier
defined in defined in
<xref target="section_58905D7A-06B1-4469-964A-DAC607DAC500" format="default" sec tionFormat="of"/> <xref target="section_58905D7A-06B1-4469-964A-DAC607DAC500" format="default" />
in that message's ProtocolNameList value. in that message's ProtocolNameList value.
</t> </t>
<t> <t>
If the server responds incorrectly If the server responds incorrectly
(for instance, if the "ServerHello" message does not conform to the above requir ements), (for instance, if the "ServerHello" message does not conform to the above requir ements),
the client <bcp14>MUST NOT</bcp14> establish a TLS session for use with RPC the client <bcp14>MUST NOT</bcp14> establish a TLS session for use with RPC
on this connection. on this connection.
See See
<xref target="RFC7301" format="default" sectionFormat="of"/> <xref target="RFC7301" format="default" />
for further details about how to form these messages properly. for further details about how to form these messages properly.
</t> </t>
<section <section
anchor="section_CC204592-F561-49BD-B1C9-DE0FF7F0E7AB" anchor="section_CC204592-F561-49BD-B1C9-DE0FF7F0E7AB"
numbered="true" numbered="true"
removeInRFC="false" removeInRFC="false"
toc="default"> toc="default">
<name>Base Transport Considerations</name> <name>Base Transport Considerations</name>
<t> <t>
There is traditionally a strong association between an RPC program There is frequently a strong association between an RPC program and a
and a destination port number. particular destination port number. The use of TLS or DTLS does not change that
The use of TLS or DTLS does not change that association. association. Thus, it is frequently, though not always, the case that a
Thus it is frequently -- single TLS session carries traffic for only one RPC program.
though not always --
the case that a single TLS session
carries traffic for only one RPC program.
</t> </t>
<section <section
anchor="section_74B43C7E-5ADC-4FBD-B4EA-FF8F470994A8" anchor="section_74B43C7E-5ADC-4FBD-B4EA-FF8F470994A8"
numbered="true" numbered="true"
removeInRFC="false" removeInRFC="false"
toc="default"> toc="default">
<name>Protected Operation on TCP</name> <name>Protected Operation on TCP</name>
<t> <t>
The use of the Transport Layer Security (TLS) protocol The use of the TLS protocol
<xref target="RFC8446" format="default" sectionFormat="of"/> <xref target="RFC8446" format="default" />
protects RPC on TCP connections. protects RPC on TCP connections.
Typically, Typically,
once an RPC client completes the TCP handshake, once an RPC client completes the TCP handshake,
it uses the mechanism described in it uses the mechanism described in
<xref target="section_0A03673B-14BA-4228-8A8A-F76AA318CA73" format="default" sec <xref target="section_0A03673B-14BA-4228-8A8A-F76AA318CA73" format="default" />
tionFormat="of"/> to discover RPC-with-TLS support for that RPC program on that connection.
to discover RPC-over-TLS support for that RPC program on that connection.
Until an AUTH_TLS probe is done on a connection, Until an AUTH_TLS probe is done on a connection,
the RPC server treats all traffic as RPC messages. the RPC server treats all traffic as RPC messages.
If spurious traffic appears on a TCP connection If spurious traffic appears on a TCP connection
between the initial clear-text AUTH_TLS probe between the initial cleartext AUTH_TLS probe
and and
the TLS session handshake, the TLS session handshake,
receivers <bcp14>MUST</bcp14> discard that data without response receivers <bcp14>MUST</bcp14> discard that data without response
and then <bcp14>SHOULD</bcp14> drop the connection. and then <bcp14>SHOULD</bcp14> drop the connection.
</t> </t>
<t> <t>
The protocol convention specified in the current document The protocol convention specified in the current document
assumes there can be no more than one concurrent TLS session assumes there can be no more than one concurrent TLS session
per TCP connection. per TCP connection.
This is true of current generations of TLS, This is true of current generations of TLS,
but might be different in a future version of TLS. but might be different in a future version of TLS.
</t> </t>
<t> <t>
Once a TLS session is established on a TCP connection, Once a TLS session is established on a TCP connection,
no further clear-text communication can occur on that connection no further cleartext communication can occur on that connection
until the session is terminated. until the session is terminated.
The use of TLS does not alter RPC record framing used on TCP transports. The use of TLS does not alter RPC record framing used on TCP transports.
</t> </t>
<t> <t>
Furthermore, Furthermore,
if an RPC server responds with PROG_UNAVAIL if an RPC server responds with PROG_UNAVAIL
to an RPC Call within an established TLS session, to an RPC Call within an established TLS session,
that does not imply that RPC server will subsequently that does not imply that RPC server will subsequently
reject the same RPC program on a different TCP connection. reject the same RPC program on a different TCP connection.
</t> </t>
<t> <t>
Reverse-direction operation occurs only on connected transports such as TCP Reverse-direction operation occurs only on connected transports such as TCP
(see (see <xref target="RFC8167" section="2" format="default"
<xref target="RFC8167" section="2" format="default" sectionFormat="of"/>). sectionFormat="of"/>). To protect reverse-direction RPC operations, the RPC
To protect reverse-direction RPC operations, server does not establish a separate TLS session on the TCP connection but
the RPC server does not establish a separate TLS session on the TCP connection, instead uses the existing TLS session on that connection to protect these
but instead uses the existing TLS session on that connection to protect operations.
these operations.
</t> </t>
<t> <t>
When operation is complete, When operation is complete,
an RPC peer terminates a TLS session by sending a TLS Closure Alert. an RPC peer terminates a TLS session by sending a TLS closure alert.
It may then close the TCP connection. It may then close the TCP connection.
</t> </t>
</section> </section>
<section <section
anchor="section_B8BF600E-96DC-4C82-AADF-D593826E9B75" anchor="section_B8BF600E-96DC-4C82-AADF-D593826E9B75"
numbered="true" numbered="true"
removeInRFC="false" removeInRFC="false"
toc="default"> toc="default">
<name>Protected Operation on UDP</name> <name>Protected Operation on UDP</name>
<t> <t>
RFC Editor: The use of the DTLS protocol
In the following section, <xref target="RFC9147" format="default" />
please replace TBD with the connection_id extension number
that is to be assigned in
<xref target="I-D.ietf-tls-dtls-connection-id" format="default" sectionFormat="o
f"/>.
And, please remove this Editor's Note
before this document is published.
</t>
<t>
The use of the Datagram Transport Layer Security (DTLS) protocol
<xref target="I-D.ietf-tls-dtls13" format="default" sectionFormat="of"/>
protects RPC carried in UDP datagrams. protects RPC carried in UDP datagrams.
As soon as a client initializes a UDP socket As soon as a client initializes a UDP socket
for use with an RPC service, for use with an RPC service,
it uses the mechanism described in it uses the mechanism described in
<xref target="section_0A03673B-14BA-4228-8A8A-F76AA318CA73" format="default" sec <xref target="section_0A03673B-14BA-4228-8A8A-F76AA318CA73" format="default" />
tionFormat="of"/> to discover RPC-with-DTLS support for that RPC program on that port.
to discover RPC-over-DTLS support for that RPC program on that port.
If spurious traffic appears on a 5-tuple between If spurious traffic appears on a 5-tuple between
the initial clear-text AUTH_TLS probe the initial cleartext AUTH_TLS probe
and and
the DTLS association handshake, the DTLS association handshake,
receivers receivers
<bcp14>MUST</bcp14> <bcp14>MUST</bcp14>
discard that traffic without response. discard that traffic without response.
</t> </t>
<t> <t>
Using DTLS does not introduce Using DTLS does not introduce
reliable reliable
or or
skipping to change at line 781 skipping to change at line 702
semantics to RPC on UDP. semantics to RPC on UDP.
The use of DTLS record replay protection is <bcp14>REQUIRED</bcp14> The use of DTLS record replay protection is <bcp14>REQUIRED</bcp14>
when transporting RPC traffic. when transporting RPC traffic.
</t> </t>
<t> <t>
Each RPC message <bcp14>MUST</bcp14> fit in a single DTLS record. Each RPC message <bcp14>MUST</bcp14> fit in a single DTLS record.
DTLS encapsulation has overhead, DTLS encapsulation has overhead,
which reduces the Packetization Layer Path MTU (PLPMTU) which reduces the Packetization Layer Path MTU (PLPMTU)
and thus the maximum RPC payload size. and thus the maximum RPC payload size.
A possible PLPMTU discovery mechanism is offered in A possible PLPMTU discovery mechanism is offered in
<xref target="RFC8899" format="default" sectionFormat="of"/>. <xref target="RFC8899" format="default" />.
</t> </t>
<t> <t>
The current document does not specify a mechanism The current document does not specify a mechanism
that enables a server to distinguish between that enables a server to distinguish between
DTLS traffic DTLS traffic
and and
unprotected RPC traffic unprotected RPC traffic
directed to the same port. directed to the same port.
To make this distinction, To make this distinction,
each peer matches ingress datagrams each peer matches ingress datagrams
that appear to be DTLS traffic to existing DTLS session state. that appear to be DTLS traffic to existing DTLS session state.
A peer treats any datagram that fails the matching process as an RPC message. A peer treats any datagram that fails the matching process as an RPC message.
</t> </t>
<t> <t>
Multi-homed RPC clients and servers may send protected RPC messages Multihomed RPC clients and servers may send protected RPC messages
via network interfaces that were not involved in the handshake that via network interfaces that were not involved in the handshake that
established the DTLS session. established the DTLS session.
Therefore, when protecting RPC traffic, Therefore, when protecting RPC traffic,
each DTLS handshake <bcp14>MUST</bcp14> include the "connection_id(TBD)" extensi on each DTLS handshake <bcp14>MUST</bcp14> include the "connection_id(54)" extensio n
described in described in
<xref target="I-D.ietf-tls-dtls13" section="9" format="default" sectionFormat="o <xref target="RFC9147" section="9" format="default" sectionFormat="of"/>,
f"/>, and RPC-with-DTLS peer endpoints
and RPC-over-DTLS peer endpoints
<bcp14>MUST</bcp14> <bcp14>MUST</bcp14>
provide a ConnectionID provide a ConnectionID
with a non-zero length. with a nonzero length.
Endpoints implementing RPC programs Endpoints implementing RPC programs
that expect a significant number of concurrent clients that expect a significant number of concurrent clients
<bcp14>SHOULD</bcp14> <bcp14>SHOULD</bcp14>
employ ConnectionIDs of at least 4 bytes in length. employ ConnectionIDs of at least 4 bytes in length.
</t> </t>
<t> <t>
Sending a TLS Closure Alert terminates a DTLS session. Sending a TLS closure alert terminates a DTLS session. Because neither DTLS
Because neither DTLS nor UDP provide in-order delivery, nor UDP provide in-order delivery, after session closure there can be
after session closure there can be ambiguity ambiguity as to whether a datagram should be interpreted as DTLS protected or
as to whether a datagram should be interpreted as DTLS protected or not. not. Therefore, receivers <bcp14>MUST</bcp14> discard datagrams exchanged
Therefore receivers using the same 5-tuple that just terminated the DTLS session for a sufficient
<bcp14>MUST</bcp14> length of time to ensure that retransmissions have ceased and packets already
discard datagrams in the network have been delivered. In the absence of more specific data, a
exchanged using the same 5-tuple that just period of 60 seconds is expected to suffice.
terminated the DTLS session for a
sufficient length of time to ensure that retransmissions have ceased and
packets already in the network have been delivered.
In the absence of more specific data,
a period of 60 seconds is expected to suffice.
</t> </t>
</section> </section>
<section <section
anchor="section_BFCC24B1-E6D4-4ABC-A5F3-B71E8E96878F" anchor="section_BFCC24B1-E6D4-4ABC-A5F3-B71E8E96878F"
numbered="true" numbered="true"
removeInRFC="false" removeInRFC="false"
toc="default"> toc="default">
<name>Protected Operation on Other Transports</name> <name>Protected Operation on Other Transports</name>
<t> <t>
skipping to change at line 843 skipping to change at line 759
toc="default"> toc="default">
<name>Protected Operation on Other Transports</name> <name>Protected Operation on Other Transports</name>
<t> <t>
Transports that provide intrinsic TLS-level security Transports that provide intrinsic TLS-level security
(e.g., QUIC) (e.g., QUIC)
need to be addressed separately from the current document. need to be addressed separately from the current document.
In such cases, the use of TLS is not opportunistic In such cases, the use of TLS is not opportunistic
as it can be for TCP or UDP. as it can be for TCP or UDP.
</t> </t>
<t> <t>
RPC-over-RDMA can make use of transport layer security RPC-over-RDMA can make use of transport layer security
below the RDMA transport layer below the RDMA transport layer
<xref target="RFC8166" format="default" sectionFormat="of"/>. <xref target="RFC8166" format="default" />.
The exact mechanism is not within the scope of the current document. The exact mechanism is not within the scope of the current document.
Because there might not be other provisions Because there might not be other provisions
to exchange client and server certificates, to exchange client and server certificates,
authentication material exchange authentication material exchange
needs to be provided by facilities needs to be provided by facilities
within a future version within a future version
of the RPC-over-RDMA transport protocol. of the RPC-over-RDMA transport protocol.
</t> </t>
</section> </section>
skipping to change at line 875 skipping to change at line 792
TLS can perform peer authentication TLS can perform peer authentication
using any of the following mechanisms. using any of the following mechanisms.
</t> </t>
<section <section
anchor="section_7A68F518-2C02-4705-8218-4F13E51372F4" anchor="section_7A68F518-2C02-4705-8218-4F13E51372F4"
numbered="true" numbered="true"
removeInRFC="false" removeInRFC="false"
toc="default"> toc="default">
<name>X.509 Certificates Using PKIX Trust</name> <name>X.509 Certificates Using PKIX Trust</name>
<t> <t>
X.509 certificates are specified in X.509 certificates are specified in
<xref target="X.509" format="default" sectionFormat="of"/>. <xref target="X.509" format="default"/>.
<xref target="RFC5280" format="default" sectionFormat="of"/> <xref target="RFC5280" format="default"/>
provides a profile of Internet PKI X.509 public key infrastructure. provides a profile of Internet PKI X.509 public key infrastructure.
RPC-over-TLS implementations are RPC-with-TLS implementations are
<bcp14>REQUIRED</bcp14> <bcp14>REQUIRED</bcp14>
to support the PKIX mechanism described in to support the PKIX mechanism described in
<xref target="RFC5280" format="default" sectionFormat="of"/>. <xref target="RFC5280" format="default"/>.
</t> </t>
<t> <t>
The rules and guidelines defined in The rules and guidelines defined in
<xref target="RFC6125" format="default" sectionFormat="of"/> <xref target="RFC6125" format="default"/>
apply to RPC-over-TLS certificates apply to RPC-with-TLS certificates
with the following considerations: with the following considerations:
</t> </t>
<ul spacing="normal" bare="false" empty="false"> <ul spacing="normal">
<li> <li>
The DNS-ID identifier type is a subjectAltName extension The DNS-ID identifier type is a subjectAltName extension that contains a
that contains a dNSName, as defined in dNSName, as defined in <xref target="RFC5280" sectionFormat="of"
<xref target="RFC5280" section="4.2.1.6" format="default" sectionFormat="of"/>. section="4.2.1.6"/>. Support for the DNS-ID identifier type
Support for the DNS-ID identifier type is is <bcp14>REQUIRED</bcp14> in RPC-with-TLS client and server implementations.
<bcp14>REQUIRED</bcp14> Certification authorities that issue such certificates <bcp14>MUST</bcp14>
in RPC-over-TLS client and server implementations.
Certification authorities that issue such certificates
<bcp14>MUST</bcp14>
support the DNS-ID identifier type. support the DNS-ID identifier type.
</li> </li>
<li> <li>
To specify the identity of an RPC peer as To specify the identity of an RPC peer as a domain name, the certificate
a domain name, <bcp14>MUST</bcp14> contain a subjectAltName extension that contains a
the certificate dNSName. DNS domain names in RPC-with-TLS certificates <bcp14>MUST NOT</bcp14>
<bcp14>MUST</bcp14> contain the wildcard character '*' within the identifier.
contain a subjectAltName extension that contains a dNSName.
DNS domain names in RPC-over-TLS certificates
<bcp14>MUST NOT</bcp14>
contain the wildcard character '*'
within the identifier.
</li> </li>
<li> <li>
To specify the identity of an RPC peer as To specify the identity of an RPC peer as a network identifier (netid) or a univ
a network identifier (netid) ersal network address (uaddr), the certificate <bcp14>MUST</bcp14> contain a sub
or jectAltName extension that contains an iPAddress.
a universal network address (uaddr),
the certificate
<bcp14>MUST</bcp14>
contain a subjectAltName extension that contains an iPAddress.
</li> </li>
</ul> </ul>
<t> <t>
When validating a server certificate, When validating a server certificate,
an RPC-over-TLS client implementation an RPC-with-TLS client implementation
takes the following into account: takes the following into account:
</t> </t>
<ul spacing="normal" bare="false" empty="false"> <ul spacing="normal">
<li> <li>
Certificate validation Certificate validation
<bcp14>MUST</bcp14> <bcp14>MUST</bcp14>
include the verification rules as per include the verification rules as per
<xref target="RFC5280" section="6" format="default" sectionFormat="of"/> <xref target="RFC5280" section="6" format="default" sectionFormat="of"/>
and and
<xref target="RFC6125" section="6" format="default" sectionFormat="of"/>. <xref target="RFC6125" section="6" format="default" sectionFormat="of"/>.
</li> </li>
<li> <li>
Server certificate validation Server certificate validation
skipping to change at line 951 skipping to change at line 858
include a check on whether include a check on whether
the locally configured expected the locally configured expected
DNS-ID DNS-ID
or or
iPAddress subjectAltName iPAddress subjectAltName
of the server that is contacted of the server that is contacted
matches its presented certificate. matches its presented certificate.
</li> </li>
<li> <li>
For RPC services accessed by their For RPC services accessed by their
network identifiers (netids) netids
and and
universal network addresses (uaddr), uaddrs,
the iPAddress subjectAltName the iPAddress subjectAltName
<bcp14>MUST</bcp14> <bcp14>MUST</bcp14>
be present in the certificate be present in the certificate
and and
<bcp14>MUST</bcp14> <bcp14>MUST</bcp14>
exactly match the address represented by the universal network address. exactly match the address represented by the universal network address.
</li> </li>
</ul> </ul>
<t> <t>
An RPC client's An RPC client's domain name and IP address are often assigned dynamically;
domain name thus, RPC servers cannot rely on those to verify client certificates.
and Therefore, when an RPC-with-TLS client presents a certificate to an
IP address RPC-with-TLS server, the server takes the following into account:
are often assigned dynamically,
thus RPC servers cannot rely on those to verify client certificates.
Therefore, when an RPC-over-TLS client presents a certificate
to an RPC-over-TLS server,
the server takes the following into account:
</t> </t>
<ul spacing="normal" bare="false" empty="false"> <ul spacing="normal">
<li> <li>
The server The server <bcp14>MUST</bcp14> use a procedure conformant to <xref
<bcp14>MUST</bcp14> target="RFC5280" section="6" format="default" sectionFormat="of"/> to
use a procedure conformant to validate the client certificate's certification path.
<xref target="RFC5280" section="6" format="default" sectionFormat="of"/>)
to validate the client certificate's certification path.
</li> </li>
<li> <li>
The tuple (serial number of the presented certificate; Issuer) The tuple (serial number of the presented certificate; Issuer) uniquely
uniquely identifies the RPC client. identifies the RPC client. The meaning and syntax of these fields is defined
The meaning and syntax of these fields is defined in in <xref target="RFC5280" section="4" format="default" sectionFormat="of"/>.
<xref target="RFC5280" section="4" format="default" sectionFormat="of"/>).
</li> </li>
</ul> </ul>
<t> <t>
RPC-over-TLS implementations RPC-with-TLS implementations
<bcp14>MAY</bcp14> <bcp14>MAY</bcp14>
allow the configuration allow the configuration
of a set of additional properties of the certificate of a set of additional properties of the certificate
to check for a peer's authorization to communicate to check for a peer's authorization to communicate
(e.g., (e.g.,
a set of allowed values in subjectAltName:URI, a set of allowed values in subjectAltName:URI,
a set of allowed X.509v3 Certificate Policies, a set of allowed X.509v3 Certificate Policies,
or or
a set of extended key usages). a set of extended key usages).
</t> </t>
skipping to change at line 1001 skipping to change at line 901
<bcp14>MAY</bcp14> <bcp14>MAY</bcp14>
allow the configuration allow the configuration
of a set of additional properties of the certificate of a set of additional properties of the certificate
to check for a peer's authorization to communicate to check for a peer's authorization to communicate
(e.g., (e.g.,
a set of allowed values in subjectAltName:URI, a set of allowed values in subjectAltName:URI,
a set of allowed X.509v3 Certificate Policies, a set of allowed X.509v3 Certificate Policies,
or or
a set of extended key usages). a set of extended key usages).
</t> </t>
<t> <t>
When the configured set of trust anchors changes When the configured set of trust anchors changes (e.g., removal of a
(e.g., removal of a CA from the list of trusted CAs; Certification Authority (CA) from the list of trusted CAs; issuance of a new Cer
issuance of a new CRL for a given CA), tificate Revocation List (CRL)
implementations for a given CA), implementations <bcp14>SHOULD</bcp14> reevaluate the
<bcp14>SHOULD</bcp14> certificate originally presented in the context of the new configuration and
reevaluate the certificate originally presented
in the context of the new configuration
and
terminate the TLS session if the certificate is no longer trustworthy. terminate the TLS session if the certificate is no longer trustworthy.
</t> </t>
<section <section
anchor="section_685D3F88-94FF-4C91-8CCB-860DBA602B2F" anchor="section_685D3F88-94FF-4C91-8CCB-860DBA602B2F"
numbered="true" numbered="true"
removeInRFC="false" removeInRFC="false"
toc="default"> toc="default">
<name>Extended Key Usage Values</name> <name>Extended Key Usage Values</name>
<t> <t>
<xref target="RFC5280" section="4.2.1.12" format="default" sectionFormat="of"/> <xref target="RFC5280" section="4.2.1.12" format="default" sectionFormat="of"/>
specifies the extended key usage X.509 certificate extension. specifies the extended key usage X.509 certificate extension.
This extension, which may appear in end-entity certificates, This extension, which may appear in end-entity certificates,
indicates one or more purposes for which the certified public key may be used indicates one or more purposes for which the certified public key may be used
in addition to or in place of the basic purposes indicated in the key usage exte nsion. in addition to or in place of the basic purposes indicated in the key usage exte nsion.
</t> </t>
<t> <t>
The current document defines two new KeyPurposeId values: The current document defines two new KeyPurposeId values:
one that identifies the RPC-over-TLS peer as an RPC client, one that identifies the RPC-with-TLS peer as an RPC client,
and and
one that identifies the RPC-over-TLS peer as an RPC server. one that identifies the RPC-with-TLS peer as an RPC server.
</t> </t>
<t> <t>
The inclusion of the RPC server value (id-kp-rpcTLSServer) The inclusion of the RPC server value (id-kp-rpcTLSServer)
indicates that the certificate has been issued indicates that the certificate has been issued
for allowing the holder to process RPC transactions. for allowing the holder to process RPC transactions.
</t> </t>
<t> <t>
The inclusion of the RPC client value (id-kp-rpcTLSClient) The inclusion of the RPC client value (id-kp-rpcTLSClient)
indicates that the certificate has been issued indicates that the certificate has been issued
for allowing the holder to request RPC transactions. for allowing the holder to request RPC transactions.
skipping to change at line 1052 skipping to change at line 949
</section> </section>
</section> </section>
<section <section
anchor="section_6DA9ED5F-BAD9-4126-95B7-E2331655A01E" anchor="section_6DA9ED5F-BAD9-4126-95B7-E2331655A01E"
numbered="true" numbered="true"
removeInRFC="false" removeInRFC="false"
toc="default"> toc="default">
<name>Pre-Shared Keys</name> <name>Pre-shared Keys</name>
<t>
This mechanism is <bcp14>OPTIONAL</bcp14> to implement.
In this mode, the RPC peer can be uniquely identified
by keying material that has been shared out-of-band
(see
<xref target="RFC8446" section="2.2" format="default" sectionFormat="of"/>).
The
PSK Identifier
<bcp14>SHOULD</bcp14>
be exposed at the RPC layer.
</t>
</section>
</section>
</section>
<section
anchor="section_88BBA4D6-ED42-4FE6-A208-9D277B68729A"
numbered="true"
removeInRFC="true"
toc="default">
<name>Implementation Status</name>
<t> <t>
This section records the status of known implementations of the This mechanism is <bcp14>OPTIONAL</bcp14> to implement. In this mode, the RPC
protocol defined by this specification at the time of posting of peer can be uniquely identified by keying material that has been shared
this Internet-Draft, and is based on a proposal described in out of band (see <xref target="RFC8446" section="2.2" format="default"
<xref target="RFC7942" format="default" sectionFormat="of"/>. sectionFormat="of"/>). The PSK Identifier <bcp14>SHOULD</bcp14> be exposed at th
The description of implementations in this section is e RPC layer.
intended to assist the IETF in its decision processes in
progressing drafts to RFCs.
</t>
<t>
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.
</t> </t>
<section
anchor="section_94AA7844-E393-4353-A35D-DA01D13C909B"
numbered="true"
removeInRFC="false"
toc="default">
<name>DESY NFS server</name>
<dl newline="false" spacing="normal" indent="11">
<dt>Organization:</dt>
<dd>
DESY
</dd>
<dt>URL:</dt>
<dd>
<eref target="https://desy.de"/>
</dd>
<dt>Maturity:</dt>
<dd>
Implementation will be based on mature versions of the current document.
</dd>
<dt>Coverage:</dt>
<dd>
The bulk of this specification is implemented including DTLS.
</dd>
<dt>Licensing:</dt>
<dd>
LGPL
</dd>
<dt>Implementation experience:</dt>
<dd>
The implementer has read and commented on the current document.
</dd>
</dl>
</section> </section>
<section
anchor="section_B387F281-958F-470D-B4D4-1D85907B89F1"
numbered="true"
removeInRFC="false"
toc="default">
<name>Hammerspace NFS server</name>
<dl newline="false" spacing="normal" indent="11">
<dt>Organization:</dt>
<dd>
Hammerspace
</dd>
<dt>URL:</dt>
<dd>
<eref target="https://hammerspace.com"/>
</dd>
<dt>Maturity:</dt>
<dd>
Prototype software based on early versions of the current document.
</dd>
<dt>Coverage:</dt>
<dd>
The bulk of this specification is implemented.
The use of DTLS functionality is not implemented.
</dd>
<dt>Licensing:</dt>
<dd>
Proprietary
</dd>
<dt>Implementation experience:</dt>
<dd>
No comments from implementors.
</dd>
</dl>
</section>
<section
anchor="section_BF03B3A2-4483-4404-9E7A-F60FCD850F31"
numbered="true"
removeInRFC="false"
toc="default">
<name>Linux NFS server and client</name>
<dl newline="false" spacing="normal" indent="11">
<dt>Organization:</dt>
<dd>
The Linux Foundation
</dd>
<dt>URL:</dt>
<dd>
<eref target="https://www.kernel.org"/>
</dd>
<dt>Maturity:</dt>
<dd>
Not complete.
</dd>
<dt>Coverage:</dt>
<dd>
The bulk of this specification has yet to be implemented.
The use of DTLS functionality is not planned.
</dd>
<dt>Licensing:</dt>
<dd>
GPLv2
</dd>
<dt>Implementation experience:</dt>
<dd>
A Linux in-kernel prototype is underway,
but implementation delays have resulted from the challenges of
handling a TLS handshake in a kernel environment.
Those issues stem from the architecture of TLS and the kernel,
not from the design of the RPC-over-TLS protocol.
</dd>
</dl>
</section>
<section
anchor="section_86689813-E907-4046-ADF1-58E2BF668546"
numbered="true"
removeInRFC="false"
toc="default">
<name>FreeBSD NFS server and client</name>
<dl newline="false" spacing="normal" indent="11">
<dt>Organization:</dt>
<dd>
The FreeBSD Project
</dd>
<dt>URL:</dt>
<dd>
<eref target="https://www.freebsd.org"/>
</dd>
<dt>Maturity:</dt>
<dd>
Prototype software based on early versions of the current document.
</dd>
<dt>Coverage:</dt>
<dd>
The bulk of this specification is implemented.
The use of DTLS functionality is not planned.
</dd>
<dt>Licensing:</dt>
<dd>
BSD
</dd>
<dt>Implementation experience:</dt>
<dd>
Implementers have read and commented on the current document.
</dd>
</dl>
</section> </section>
</section> </section>
<section <section
anchor="section_2AE49383-E6B2-4830-8407-995FEBF727F2" anchor="section_2AE49383-E6B2-4830-8407-995FEBF727F2"
numbered="true" numbered="true"
removeInRFC="false" removeInRFC="false"
toc="default"> toc="default">
<name>Security Considerations</name> <name>Security Considerations</name>
skipping to change at line 1246 skipping to change at line 970
</section> </section>
</section> </section>
<section <section
anchor="section_2AE49383-E6B2-4830-8407-995FEBF727F2" anchor="section_2AE49383-E6B2-4830-8407-995FEBF727F2"
numbered="true" numbered="true"
removeInRFC="false" removeInRFC="false"
toc="default"> toc="default">
<name>Security Considerations</name> <name>Security Considerations</name>
<t> <t>
One purpose of the mechanism described in the current document One purpose of the mechanism described in the current document
is to protect RPC-based applications against threats is to protect RPC-based applications against threats
to the confidentiality of RPC transactions to the confidentiality of RPC transactions
and and
RPC user identities. RPC user identities.
A taxonomy of these threats appears in A taxonomy of these threats appears in
<xref target="RFC6973" section="5" format="default" sectionFormat="of"/>. <xref target="RFC6973" section="5" format="default" sectionFormat="of"/>.
Also, Also,
<xref target="RFC7525" section="6" format="default" sectionFormat="of"/> <xref target="RFC7525" section="6" format="default" sectionFormat="of"/>
contains a detailed discussion contains a detailed discussion
of technologies used in conjunction with TLS. of technologies used in conjunction with TLS.
<xref target="RFC5280" section="8" format="default" sectionFormat="of"/> <xref target="RFC5280" section="8" format="default" sectionFormat="of"/>
covers important considerations about handling certificate material securely. covers important considerations about handling certificate material securely.
Implementers should familiarize themselves with these materials. Implementers should familiarize themselves with these materials.
</t> </t>
<t> <t>
Once a TLS session is established, Once a TLS session is established,
the RPC payload carried on TLS version 1.3 is forward-secure. the RPC payload carried on TLS version 1.3 is forward secure.
However, implementers need to be aware that replay attacks However, implementers need to be aware that replay attacks
can occur during session establishment. can occur during session establishment.
Remedies for such attacks are discussed in detail in Remedies for such attacks are discussed in detail in
<xref target="RFC8446" section="8" format="default" sectionFormat="of"/>. <xref target="RFC8446" section="8" format="default" sectionFormat="of"/>.
Further, the current document does not Further, the current document does not
provide a profile that defines the use of 0-RTT data provide a profile that defines the use of 0-RTT data
(see (see
Appendix&nbsp;E.5 of <xref target="RFC8446" format="default" sectionFormat="of" section="E.5"/>).
<xref target="RFC8446" format="default" sectionFormat="of"/>). Therefore, RPC-with-TLS implementations <bcp14>MUST NOT</bcp14>
Therefore, RPC-over-TLS implementations MUST NOT
use 0-RTT data. use 0-RTT data.
</t> </t>
<section <section
anchor="section_51737BB5-2B65-441E-AD1D-7EBF5123C079" anchor="section_51737BB5-2B65-441E-AD1D-7EBF5123C079"
numbered="true" numbered="true"
removeInRFC="false" removeInRFC="false"
toc="default"> toc="default">
<name>The Limitations of Opportunistic Security</name> <name>The Limitations of Opportunistic Security</name>
<t> <t>
Readers can find the definition of Opportunistic Security in Readers can find the definition of Opportunistic Security in
<xref target="RFC7435" format="default" sectionFormat="of"/>. <xref target="RFC7435" format="default"/>.
A discussion of its underlying principals A discussion of its underlying principles
appears in Section&nbsp;3 of that document. appears in Section <xref target="RFC7435" sectionFormat="bare" section="3"></xre
</t> f> of that document.</t>
<t> <t>
The purpose of using an explicitly opportunistic approach The purpose of using an explicitly opportunistic approach
is to enable interoperation is to enable interoperation
with implementations that do not support RPC-over-TLS. with implementations that do not support RPC-with-TLS.
A range of options is allowed by this approach, A range of options is allowed by this approach,
from "no peer authentication or encryption" from "no peer authentication or encryption"
to to
"server-only authentication with encryption" "server-only authentication with encryption"
to to
"mutual authentication with encryption". "mutual authentication with encryption".
The actual security level may indeed The actual security level may indeed
be selected based on policy and without user intervention. be selected based on policy and without user intervention.
</t> </t>
<t> <t>
In environments where interoperability is a priority, In environments where interoperability is a priority,
the security benefits of TLS are partially or entirely waived. the security benefits of TLS are partially or entirely waived.
Implementations of the mechanism described in the current document Implementations of the mechanism described in the current document
must take care to accurately represent to all RPC consumers must take care to accurately represent to all RPC consumers
the level of security that is actually in effect, the level of security that is actually in effect,
and are <bcp14>REQUIRED</bcp14> to provide an audit log and are <bcp14>REQUIRED</bcp14> to provide an audit log
of RPC-over-TLS security mode selection. of RPC-with-TLS security mode selection.
</t> </t>
<t> <t>
In all other cases, In all other cases,
the adoption, implementation, and deployment of the adoption, implementation, and deployment of
RPC-based upper-layer protocols that enforce the use of RPC-based upper-layer protocols that enforce the use of
TLS authentication and encryption TLS authentication and encryption
(when similar RPCSEC GSS services are not in use) (when similar RPCSEC_GSS services are not in use)
is strongly encouraged. is strongly encouraged.
</t> </t>
<section <section
anchor="section_8894BDD2-0E0B-47A3-A2CB-70E4D93B55B0" anchor="section_8894BDD2-0E0B-47A3-A2CB-70E4D93B55B0"
numbered="true" numbered="true"
removeInRFC="false" removeInRFC="false"
toc="default"> toc="default">
<name>STRIPTLS Attacks</name> <name>STRIPTLS Attacks</name>
<t> <t>
A classic form of attack on network protocols that initiate an association The initial AUTH_TLS probe occurs in cleartext.
in plain-text to discover support for TLS is a man-in-the-middle An on-path attacker can alter a cleartext handshake to make it
that alters the plain-text handshake to make it appear as though appear as though TLS support is not available on one or both peers.
TLS support is not available on one or both peers.
Client implementers can choose from the following to mitigate Client implementers can choose from the following to mitigate
STRIPTLS attacks: STRIPTLS attacks:
</t> </t>
<ul spacing="normal" bare="false" empty="false"> <ul spacing="normal">
<li> <li>
A TLSA record A TLSA record
<xref target="RFC6698" format="default" sectionFormat="of"/> <xref target="RFC6698" format="default"/>
can alert clients that TLS is expected to work, can alert clients that TLS is expected to work, and provide a binding of
and provide a binding of hostname to X.509 identity. a hostname to the X.509 identity. If TLS cannot be negotiated or authentication
If TLS cannot be negotiated or authentication fails, fails, the client disconnects and reports the problem. When an opportunistic
the client disconnects and reports the problem. security policy is in place, a client <bcp14>SHOULD</bcp14> check for the
When an opportunistic security policy is in place, existence of a TLSA record for the target server before initiating an
a client RPC-with-TLS association.
<bcp14>SHOULD</bcp14>
check for the existence of a TLSA record for the target
server before initiating an RPC-over-TLS association.
</li> </li>
<li> <li>
Client security policy can require Client security policy can require
that a TLS session is established on every connection. that a TLS session is established on every connection.
If an attacker spoofs the handshake, If an attacker spoofs the handshake,
the client disconnects and reports the problem. the client disconnects and reports the problem.
This policy prevents an attacker from causing the client to silently fall back t
o plaintext. This policy prevents an attacker from causing the association to
fall back to cleartext silently.
If TLSA records are not available, this approach is strongly encouraged. If TLSA records are not available, this approach is strongly encouraged.
</li> </li>
</ul> </ul>
</section> </section>
<section <section
anchor="section_9C03417D-1D3D-4D43-BC43-6F7387736AF7" anchor="section_9C03417D-1D3D-4D43-BC43-6F7387736AF7"
numbered="true" numbered="true"
removeInRFC="false" removeInRFC="false"
toc="default"> toc="default">
<name>Privacy Leakage Before Session Establishment</name> <name>Privacy Leakage before Session Establishment</name>
<t> <t>
As mentioned earlier, As mentioned earlier,
communication between an RPC client and server communication between an RPC client and server
appears in the clear on the network appears in the clear on the network
prior to the establishment of a TLS session. prior to the establishment of a TLS session.
This clear-text information usually includes This cleartext information usually includes
transport connection handshake exchanges, transport connection handshake exchanges,
the RPC NULL procedure probing support for TLS, the RPC NULL procedure probing support for TLS,
and the initial parts of TLS session establishment. and the initial parts of TLS session establishment.
Appendix C of <xref target="RFC8446" sectionFormat="of" section="C" format="default"/>
<xref target="RFC8446" format="default" sectionFormat="of"/> discusses precautions that can mitigate exposure during the exchange of
discusses precautions that can mitigate exposure during connection handshake information and TLS certificate material that might
the exchange of connection handshake information enable attackers to track the RPC client. Note that when PSK authentication
and is used, the PSK identifier is exposed during the TLS handshake and can be
TLS certificate material that might enable attackers used to track the RPC client.
to track the RPC client.
Note that when PSK authentication is used,
the PSK identifier is exposed during the TLS handshake,
and can be used to track the RPC client.
</t> </t>
<t> <t>
Any RPC traffic that appears on the network before Any RPC traffic that appears on the network before
a TLS session has been established is vulnerable to a TLS session has been established is vulnerable to
monitoring or undetected modification. monitoring or undetected modification.
A secure client implementation limits or prevents A secure client implementation limits or prevents
any RPC exchanges that are not protected. any RPC exchanges that are not protected.
</t> </t>
<t> <t>
The exception to this edict is The exception to this edict is
skipping to change at line 1413 skipping to change at line 1132
</section> </section>
<section <section
anchor="section_B9F8A982-CB0E-40FC-9460-680E89DB0001" anchor="section_B9F8A982-CB0E-40FC-9460-680E89DB0001"
numbered="true" numbered="true"
removeInRFC="false" removeInRFC="false"
toc="default"> toc="default">
<name>TLS Identity Management on Clients</name> <name>TLS Identity Management on Clients</name>
<t> <t>
The goal of the RPC-over-TLS protocol extension The goal of RPC-with-TLS is to hide the content of RPC requests while they are
is to hide the content of RPC requests while they are in transit. in transit. RPC-with-TLS protocol by itself cannot protect against
The RPC-over-TLS protocol by itself cannot protect exposure of a user's RPC requests to other users on the same client.
against exposure of a user's RPC requests to other users on the same client.
</t> </t>
<t> <t>
Moreover, client implementations are free to transmit RPC requests Moreover, client implementations are free to transmit RPC requests
for more than one RPC user using the same TLS session. for more than one RPC user using the same TLS session.
Depending on the details of the client RPC implementation, Depending on the details of the client RPC implementation,
this means that the client's TLS credentials this means that the client's TLS credentials
are potentially visible to every RPC user that shares a TLS session. are potentially visible to every RPC user that shares a TLS session.
Privileged users may also be able to access this TLS identity. Privileged users may also be able to access this TLS identity.
</t> </t>
<t> <t>
skipping to change at line 1446 skipping to change at line 1164
anchor="section_552B02A0-F19E-4B46-809C-672A6AE931A1" anchor="section_552B02A0-F19E-4B46-809C-672A6AE931A1"
numbered="true" numbered="true"
removeInRFC="false" removeInRFC="false"
toc="default"> toc="default">
<name>Security Considerations for AUTH_SYS on TLS</name> <name>Security Considerations for AUTH_SYS on TLS</name>
<t> <t>
Using a TLS-protected transport Using a TLS-protected transport
when the AUTH_SYS authentication flavor is in use when the AUTH_SYS authentication flavor is in use
addresses several longstanding weaknesses in AUTH_SYS addresses several longstanding weaknesses in AUTH_SYS
(as detailed in (as detailed in
<xref target="section_C7FB9DB5-5F4F-45AD-8BF7-74FFCA08BEBB" format="default" sec tionFormat="of"/>). <xref target="section_C7FB9DB5-5F4F-45AD-8BF7-74FFCA08BEBB" format="default"/>).
TLS augments AUTH_SYS by providing both TLS augments AUTH_SYS by providing both
integrity protection and confidentiality integrity protection and confidentiality
that AUTH_SYS lacks. that AUTH_SYS lacks.
TLS protects TLS protects
data payloads, data payloads,
RPC headers, RPC headers,
and and
user identities user identities
against monitoring and alteration while in transit. against monitoring and alteration while in transit.
</t> </t>
<t> <t>
TLS guards against in-transit insertion and deletion of RPC messages, TLS guards against in-transit insertion and deletion of RPC messages, thus
thus ensuring the integrity of the message stream ensuring the integrity of the message stream between RPC client and server.
between RPC client and server. DTLS does not provide full message stream protection, but it does enable
DTLS does not provide full message stream protection, receivers to reject nonparticipant messages. In particular, transport-layer
but it does enable receivers to reject non-participant messages. encryption plus peer authentication protects receiving eXternal Data
In particular, transport layer encryption plus peer authentication Representation (XDR) decoders from deserializing untrusted data, a common
protects receiving XDR decoders from deserializing untrusted data, coding vulnerability. However, these decoders would still be exposed to
a common coding vulnerability. untrusted input in the case of the compromise of a trusted peer or Certification
However, these decoders would still be exposed to untrusted input Authority.
in the case of the compromise of a trusted peer or Certificate Authority.
</t> </t>
<t> <t>
The use of TLS enables strong authentication The use of TLS enables strong authentication
of the communicating RPC peers, of the communicating RPC peers,
providing a degree of non-repudiation. providing a degree of non-repudiation.
When AUTH_SYS is used with TLS, When AUTH_SYS is used with TLS,
but the RPC client is unauthenticated, but the RPC client is unauthenticated,
the RPC server still acts on RPC requests the RPC server still acts on RPC requests
for which there is no trustworthy authentication. for which there is no trustworthy authentication.
In-transit traffic is protected, but the RPC client itself In-transit traffic is protected, but the RPC client itself
skipping to change at line 1509 skipping to change at line 1226
</t> </t>
</section> </section>
<section <section
anchor="section_55D006D3-8CA6-4D7F-AF0D-BFB0FFEF7595" anchor="section_55D006D3-8CA6-4D7F-AF0D-BFB0FFEF7595"
numbered="true" numbered="true"
removeInRFC="false" removeInRFC="false"
toc="default"> toc="default">
<name>Best Security Policy Practices</name> <name>Best Security Policy Practices</name>
<t> <t>
RPC-over-TLS implementations and deployments RPC-with-TLS implementations and deployments
are strongly encouraged to adhere to the following policies are strongly encouraged to adhere to the following policies
to achieve the strongest possible security with RPC-over-TLS. to achieve the strongest possible security with RPC-with-TLS.
</t> </t>
<ul spacing="normal" bare="false" empty="false"> <ul spacing="normal">
<li> <li>
When using AUTH_NULL or AUTH_SYS, both peers are When using AUTH_NULL or AUTH_SYS, both peers are
<bcp14>RECOMMENDED</bcp14> <bcp14>RECOMMENDED</bcp14>
to have DNSSEC TLSA records, to have DNSSEC TLSA records,
keys with which to perform mutual peer authentication keys with which to perform mutual peer authentication
using one of the methods described in using one of the methods described in
<xref target="section_936921ED-67BB-46BF-B316-6740E07F6652" format="default" sec tionFormat="of"/>, <xref target="section_936921ED-67BB-46BF-B316-6740E07F6652" format="default"/>,
and and
a security policy that requires mutual peer authentication a security policy that requires mutual peer authentication
and and
rejection of a connection when host authentication fails. rejection of a connection when host authentication fails.
</li> </li>
<li> <li>
RPCSEC GSS provides integrity and privacy services RPCSEC_GSS provides integrity and privacy services that are largely redundant
which are largely redundant when TLS is in use. when TLS is in use. These services <bcp14>SHOULD</bcp14> be disabled in that
These services case.
<bcp14>SHOULD</bcp14>
be disabled in that case.
</li> </li>
</ul> </ul>
</section> </section>
</section> </section>
<section <section
anchor="section_7B126473-2A13-453B-9BCA-66BC11B7B018" anchor="section_7B126473-2A13-453B-9BCA-66BC11B7B018"
numbered="true" numbered="true"
removeInRFC="false" removeInRFC="false"
toc="default"> toc="default">
<name>IANA Considerations</name> <name>IANA Considerations</name>
<t>
RFC Editor: In the following subsections,
please replace RFC-TBD with the RFC number assigned to this document.
And, please remove this Editor's Note
before this document is published.
</t>
<section <section
anchor="section_2CD51855-CE40-4B8D-A220-F211C477964F" anchor="section_2CD51855-CE40-4B8D-A220-F211C477964F"
numbered="true" numbered="true"
removeInRFC="false" removeInRFC="false"
toc="default"> toc="default">
<name>RPC Authentication Flavor</name> <name>RPC Authentication Flavor</name>
<t> <t>
Following Appendix B of Following <xref target="RFC5531" format="default" section="B"
<xref target="RFC5531" format="default" sectionFormat="of"/>, sectionFormat="of"/>, an entry has been added to the "RPC
the authors request a single new entry Authentication Flavor Numbers" registry. The purpose of the new authentication
in the RPC Authentication Flavor Numbers registry. flavor is to signal the use of TLS with RPC. This new flavor is not a
The purpose of the new authentication flavor pseudo-flavor.
is to signal the use of TLS with RPC.
This new flavor is not a pseudo-flavor.
</t> </t>
<t> <t>
The fields in the new entry are assigned as follows: The fields in the new entry have been assigned as follows:
</t> </t>
<dl newline="false" spacing="normal"> <dl newline="false" spacing="normal">
<dt>Identifier String:</dt> <dt>Identifier String:</dt>
<dd> <dd>
AUTH_TLS AUTH_TLS
</dd> </dd>
<dt>Flavor Name:</dt> <dt>Flavor Name:</dt>
<dd> <dd>
TLS TLS
</dd> </dd>
<dt>Value:</dt> <dt>Value:</dt>
<dd> <dd>
7 (to be confirmed by IANA) 7
</dd> </dd>
<dt>Description:</dt> <dt>Description:</dt>
<dd> <dd>
Indicates support for RPC-over-TLS. Indicates support for RPC-with-TLS
</dd> </dd>
<dt>Reference:</dt> <dt>Reference:</dt>
<dd> <dd>
RFC-TBD RFC 9289
</dd> </dd>
</dl> </dl>
</section> </section>
<section <section
anchor="section_58905D7A-06B1-4469-964A-DAC607DAC500" anchor="section_58905D7A-06B1-4469-964A-DAC607DAC500"
numbered="true" numbered="true"
removeInRFC="false" removeInRFC="false"
toc="default"> toc="default">
<name>ALPN Identifier for SUNRPC</name> <name>ALPN Identifier for SunRPC</name>
<t> <t>
Following Following
<xref target="RFC7301" section="6" format="default" sectionFormat="of"/>, <xref target="RFC7301" section="6" format="default" sectionFormat="of"/>,
the authors request the allocation of the following value the following value has been allocated
in the "Application-Layer Protocol Negotiation (ALPN) Protocol IDs" registry. in the "TLS Application-Layer Protocol Negotiation (ALPN) Protocol IDs" registry
.
The "sunrpc" string identifies SunRPC when used over TLS. The "sunrpc" string identifies SunRPC when used over TLS.
</t> </t>
<dl newline="false" spacing="normal"> <dl newline="false" spacing="normal">
<dt>Protocol:</dt> <dt>Protocol:</dt>
<dd> <dd>
SunRPC SunRPC
</dd> </dd>
<dt>Identification Sequence:</dt> <dt>Identification Sequence:</dt>
<dd> <dd>
0x73 0x75 0x6e 0x72 0x70 0x63 ("sunrpc") 0x73 0x75 0x6e 0x72 0x70 0x63 ("sunrpc")
</dd> </dd>
<dt>Reference:</dt> <dt>Reference:</dt>
<dd> <dd>
RFC-TBD RFC 9289
</dd> </dd>
</dl> </dl>
</section> </section>
<section <section
anchor="section_62E5E930-706A-4216-9A32-D7AC5952A507" anchor="section_62E5E930-706A-4216-9A32-D7AC5952A507"
numbered="true" numbered="true"
removeInRFC="false" removeInRFC="false"
toc="default"> toc="default">
<name>Object Identifier for PKIX Extended Key Usage</name> <name>Object Identifier for PKIX Extended Key Usage</name>
skipping to change at line 1628 skipping to change at line 1335
</dd> </dd>
</dl> </dl>
</section> </section>
<section <section
anchor="section_62E5E930-706A-4216-9A32-D7AC5952A507" anchor="section_62E5E930-706A-4216-9A32-D7AC5952A507"
numbered="true" numbered="true"
removeInRFC="false" removeInRFC="false"
toc="default"> toc="default">
<name>Object Identifier for PKIX Extended Key Usage</name> <name>Object Identifier for PKIX Extended Key Usage</name>
<t> <t>
RFC Editor: In the following subsection, Per the Specification Required policy defined in <xref target="RFC8126"
please replace XXX and YYY with the IANA numbers assigned to these new entries. section="4.6" format="default" sectionFormat="of"/>, the following new values
And, please remove this Editor's Note have been registered in the "SMI Security for PKIX Extended Key Purpose"
before this document is published. registry (1.3.6.1.5.5.7.3) (see
</t> <xref target="section_685D3F88-94FF-4C91-8CCB-860DBA602B2F" format="default"/>
<t>
Per the Specification Required policy as defined in
<xref target="RFC8126" section="4.6" format="default" sectionFormat="of"/>,
the authors request the reservation of the following new values:
</t>
<ul spacing="normal" bare="false" empty="false">
<li>
The RPC-over-TLS ASN.1 module in the
"SMI Security for PKIX Extended Key Purpose" registry (1.3.6.1.5.5.7.3)
(see
<xref target="section_685D3F88-94FF-4C91-8CCB-860DBA602B2F" format="default" sec
tionFormat="of"/>
and and
<xref target="section_B08B45C1-1E10-4F7A-935B-1198BAF255C0" format="default" sec <xref target="section_B08B45C1-1E10-4F7A-935B-1198BAF255C0" format="default"/>).
tionFormat="of"/>. </t>
</li> <table>
<li> <thead>
The RPC-over-TLS client certificate extended key usage (1.3.6.1.5.5.7.3.XXX). <tr>
The description of this new entry should be "id-kp-rpcTLSClient". <th>Decimal</th>
</li> <th>Description</th>
<li> <th>Reference</th>
The RPC-over-TLS server certificate extended key usage (1.3.6.1.5.5.7.3.YYY). </tr>
The description of this new entry should be "id-kp-rpcTLSServer". </thead>
</li> <tbody>
</ul> <tr>
<td>33</td>
<td>id-kp-rpcTLSClient</td>
<td>RFC 9289</td>
</tr>
<tr>
<td>34</td>
<td>id-kp-rpcTLSServer</td>
<td>RFC 9289</td>
</tr>
</tbody>
</table>
</section>
<section anchor="section_1FB29AC3-A737-4822-B396-D33919905567" numbered="true" r
emoveInRFC="false" toc="default">
<name>Object Identifier for ASN.1 Module</name>
<t> <t>
IANA should use the current document (RFC-TBD) as the reference for the new entr ies. Per the Specification Required policy defined in <xref target="RFC8126" section= "4.6" format="default" sectionFormat="of"/>, the following new value has been re gistered in the "SMI Security for PKIX Module Identifier" registry (1.3.6.1.5.5. 7.0) (see <xref target="section_B08B45C1-1E10-4F7A-935B-1198BAF255C0"/>).
</t> </t>
<table>
<thead>
<tr>
<th>Decimal</th>
<th>Description</th>
<th>Reference</th>
</tr>
</thead>
<tbody>
<tr>
<td>105</td>
<td>id-mod-rpcWithTLS-2021</td>
<td>RFC 9289</td>
</tr>
</tbody>
</table>
</section> </section>
</section> </section>
</middle> </middle>
<back> <back>
<references> <references>
<name>References</name> <name>References</name>
<references> <references>
<name>Normative References</name> <name>Normative References</name>
<xi:include xmlns:xi="http://www.w3.org/2001/XInclude" <xi:include href="https://xml2rfc.ietf.org/public/rfc/bibxml/reference.RFC.9266.
href="https://xml2rfc.tools.ietf.org/public/rfc/bibxml3/reference.I-D.draft-iet xml"/>
f-tls-dtls13-38.xml"/> <xi:include href="https://xml2rfc.ietf.org/public/rfc/bibxml/reference.RFC.2119.
<xi:include xmlns:xi="http://www.w3.org/2001/XInclude" xml"/>
href="https://xml2rfc.tools.ietf.org/public/rfc/bibxml3/reference.I-D.draft-iet <xi:include href="https://xml2rfc.ietf.org/public/rfc/bibxml/reference.RFC.5056.
f-tls-dtls-connection-id-07.xml"/> xml"/>
<xi:include xmlns:xi="http://www.w3.org/2001/XInclude" <xi:include href="https://xml2rfc.ietf.org/public/rfc/bibxml/reference.RFC.5280.
href="https://xml2rfc.tools.ietf.org/public/rfc/bibxml3/reference.I-D.draft-iet xml"/>
f-kitten-tls-channel-bindings-for-tls13-00.xml"/> <xi:include href="https://xml2rfc.ietf.org/public/rfc/bibxml/reference.RFC.5531.
xml"/>
<xi:include xmlns:xi="http://www.w3.org/2001/XInclude" <xi:include href="https://xml2rfc.ietf.org/public/rfc/bibxml/reference.RFC.6125.
href="https://xml2rfc.tools.ietf.org/public/rfc/bibxml/reference.RFC.2119.xml"/ xml"/>
> <xi:include href="https://xml2rfc.ietf.org/public/rfc/bibxml/reference.RFC.7301.
<xi:include xmlns:xi="http://www.w3.org/2001/XInclude" xml"/>
href="https://xml2rfc.tools.ietf.org/public/rfc/bibxml/reference.RFC.5056.xml"/ <xi:include href="https://xml2rfc.ietf.org/public/rfc/bibxml/reference.RFC.7525.
> xml"/>
<xi:include xmlns:xi="http://www.w3.org/2001/XInclude" <xi:include href="https://xml2rfc.ietf.org/public/rfc/bibxml/reference.RFC.8126.
href="https://xml2rfc.tools.ietf.org/public/rfc/bibxml/reference.RFC.5280.xml"/ xml"/>
> <xi:include href="https://xml2rfc.ietf.org/public/rfc/bibxml/reference.RFC.8174.
<xi:include xmlns:xi="http://www.w3.org/2001/XInclude" xml"/>
href="https://xml2rfc.tools.ietf.org/public/rfc/bibxml/reference.RFC.5531.xml"/ <xi:include href="https://xml2rfc.ietf.org/public/rfc/bibxml/reference.RFC.8446.
> xml"/>
<xi:include xmlns:xi="http://www.w3.org/2001/XInclude" <xi:include href="https://xml2rfc.ietf.org/public/rfc/bibxml/reference.RFC.9147.
href="https://xml2rfc.tools.ietf.org/public/rfc/bibxml/reference.RFC.6125.xml"/ xml"/>
>
<xi:include xmlns:xi="http://www.w3.org/2001/XInclude"
href="https://xml2rfc.tools.ietf.org/public/rfc/bibxml/reference.RFC.7301.xml"/
>
<xi:include xmlns:xi="http://www.w3.org/2001/XInclude"
href="https://xml2rfc.tools.ietf.org/public/rfc/bibxml/reference.RFC.7525.xml"/
>
<xi:include xmlns:xi="http://www.w3.org/2001/XInclude"
href="https://xml2rfc.tools.ietf.org/public/rfc/bibxml/reference.RFC.7942.xml"/
>
<xi:include xmlns:xi="http://www.w3.org/2001/XInclude"
href="https://xml2rfc.tools.ietf.org/public/rfc/bibxml/reference.RFC.8126.xml"/
>
<xi:include xmlns:xi="http://www.w3.org/2001/XInclude"
href="https://xml2rfc.tools.ietf.org/public/rfc/bibxml/reference.RFC.8174.xml"/
>
<xi:include xmlns:xi="http://www.w3.org/2001/XInclude"
href="https://xml2rfc.tools.ietf.org/public/rfc/bibxml/reference.RFC.8446.xml"/
>
<reference anchor="X.509"> <reference anchor="X.509">
<front> <front>
<title> <title>
ITU-T X.509 - Information technology - Information technology – Open Systems
The Directory: Public-key and attribute certificate frameworks. Interconnection – The Directory: Public-key and
attribute certificate frameworks
</title> </title>
<seriesInfo name="ISO/IEC" value="9594-8"/> <seriesInfo name="ISO/IEC" value="9594-8"/>
<seriesInfo name="CCITT Recommendation" value="X.509"/> <seriesInfo name="ITU-T Recommendation" value="X.509"/>
<author> <author>
<organization showOnFrontPage="true"> <organization>
International Telephone and Telegraph Consultative Committee International Telecommunication Union
</organization> </organization>
</author> </author>
<date month="October" year="2019"/> <date month="October" year="2019"/>
<abstract>
<t>
Recommendation ITU-T X.509 | ISO/IEC 9594-8 defines frameworks for public-key in
frastructure (PKI) and privilege management infrastructure (PMI).
It introduces the basic concept of asymmetric cryptographic techniques.
It specifies the following data types: public-key certificate, attribute certifi
cate, certificate revocation list (CRL) and attribute certificate revocation lis
t (ACRL).
It also defines several certificates and CRL extensions, and it defines director
y schema information allowing PKI and PMI related data to be stored in a directo
ry.
In addition, it defines entity types, such as certification authority (CA), attr
ibute authority (AA), relying party, privilege verifier, trust broker and trust
anchor.
It specifies the principles for certificate validation, validation path, certifi
cate policy, etc.
It also includes a specification for authorization validation lists that allow f
or fast validation and restrictions on communications.
</t>
</abstract>
</front> </front>
</reference> </reference>
<reference anchor="X.680" target="https://www.itu.int/rec/T-REC-X.680">
<front>
<title>Information technology - Abstract Syntax Notation One (ASN.1)
: Specification of basic notation</title>
<author>
<organization>ITU-T</organization>
</author>
<date year="2021" month="February"/>
</front>
<seriesInfo name="ITU-T Recommendation" value="X.680"/>
</reference>
<reference anchor="X.690" target="https://www.itu.int/rec/T-REC-X.690">
<front>
<title>Information technology - ASN.1 encoding rules:
Specification of Basic Encoding Rules (BER), Canonical Encoding
Rules (CER) and Distinguished Encoding Rules (DER)
</title>
<author>
<organization>ITU-T</organization>
</author>
<date year="2021" month="February"/>
</front>
<seriesInfo name="ITU-T Recommendation" value="X.690"/>
</reference>
</references> </references>
<references> <references>
<name>Informative References</name> <name>Informative References</name>
<xi:include xmlns:xi="http://www.w3.org/2001/XInclude" <xi:include href="https://xml2rfc.ietf.org/public/rfc/bibxml/reference.RFC.1833.
href="https://xml2rfc.tools.ietf.org/public/rfc/bibxml/reference.RFC.1833.xml"/ xml"/>
> <xi:include href="https://xml2rfc.ietf.org/public/rfc/bibxml/reference.RFC.2203.
<xi:include xmlns:xi="http://www.w3.org/2001/XInclude" xml"/>
href="https://xml2rfc.tools.ietf.org/public/rfc/bibxml/reference.RFC.2203.xml"/ <xi:include href="https://xml2rfc.ietf.org/public/rfc/bibxml/reference.RFC.9110.
> xml"/>
<xi:include xmlns:xi="http://www.w3.org/2001/XInclude" <xi:include href="https://xml2rfc.ietf.org/public/rfc/bibxml/reference.RFC.6698.
href="https://xml2rfc.tools.ietf.org/public/rfc/bibxml/reference.RFC.2818.xml"/ xml"/>
> <xi:include href="https://xml2rfc.ietf.org/public/rfc/bibxml/reference.RFC.6973.
<xi:include xmlns:xi="http://www.w3.org/2001/XInclude" xml"/>
href="https://xml2rfc.tools.ietf.org/public/rfc/bibxml/reference.RFC.6698.xml"/ <xi:include href="https://xml2rfc.ietf.org/public/rfc/bibxml/reference.RFC.7258.
> xml"/>
<xi:include xmlns:xi="http://www.w3.org/2001/XInclude" <xi:include href="https://xml2rfc.ietf.org/public/rfc/bibxml/reference.RFC.7435.
href="https://xml2rfc.tools.ietf.org/public/rfc/bibxml/reference.RFC.6973.xml"/ xml"/>
> <xi:include href="https://xml2rfc.ietf.org/public/rfc/bibxml/reference.RFC.8166.
<xi:include xmlns:xi="http://www.w3.org/2001/XInclude" xml"/>
href="https://xml2rfc.tools.ietf.org/public/rfc/bibxml/reference.RFC.7258.xml"/ <xi:include href="https://xml2rfc.ietf.org/public/rfc/bibxml/reference.RFC.8167.
> xml"/>
<xi:include xmlns:xi="http://www.w3.org/2001/XInclude" <xi:include href="https://xml2rfc.ietf.org/public/rfc/bibxml/reference.RFC.8899.
href="https://xml2rfc.tools.ietf.org/public/rfc/bibxml/reference.RFC.7435.xml"/ xml"/>
>
<xi:include xmlns:xi="http://www.w3.org/2001/XInclude"
href="https://xml2rfc.tools.ietf.org/public/rfc/bibxml/reference.RFC.8166.xml"/
>
<xi:include xmlns:xi="http://www.w3.org/2001/XInclude"
href="https://xml2rfc.tools.ietf.org/public/rfc/bibxml/reference.RFC.8167.xml"/
>
<xi:include xmlns:xi="http://www.w3.org/2001/XInclude"
href="https://xml2rfc.tools.ietf.org/public/rfc/bibxml/reference.RFC.8899.xml"/
>
</references> </references>
</references> </references>
<section <section
anchor="section_C7FB9DB5-5F4F-45AD-8BF7-74FFCA08BEBB" anchor="section_C7FB9DB5-5F4F-45AD-8BF7-74FFCA08BEBB"
numbered="true" numbered="true"
removeInRFC="false" removeInRFC="false"
toc="default"> toc="default">
<name>Known Weaknesses of the AUTH_SYS Authentication Flavor</name> <name>Known Weaknesses of the AUTH_SYS Authentication Flavor</name>
<t> <t>
The ONC RPC protocol, as specified in
<xref target="RFC5531" format="default" sectionFormat="of"/>, The ONC RPC protocol, as specified in <xref target="RFC5531" format="default"/>,
provides several modes of security, provides several modes of security, commonly
traditionally referred to as "authentication flavors". referred to as "authentication flavors". Some of these flavors provide much
Some of these flavors provide much more than an authentication service. more than an authentication service. We refer to these as authentication
We refer to these as flavors, security flavors, or simply, flavors. One of the earliest and most
authentication flavors, basic flavors is AUTH_SYS, also known as AUTH_UNIX.
security flavors, <xref target="RFC5531" format="default" sectionFormat="of" section="A"/>
or simply,
flavors.
One of the earliest and most basic flavors is AUTH_SYS,
also known as AUTH_UNIX.
Appendix A of
<xref target="RFC5531" format="default" sectionFormat="of"/>
specifies AUTH_SYS. specifies AUTH_SYS.
</t> </t>
<t> <t>
AUTH_SYS assumes that the RPC client and server AUTH_SYS assumes that the RPC client and server
both use POSIX-style user and group identifiers both use POSIX-style user and group identifiers
(each user and group can be distinctly represented (each user and group can be distinctly represented
as a 32-bit unsigned integer). as a 32-bit unsigned integer).
It also assumes that the client and server It also assumes that the client and server
both use the same mapping of user and group to an integer. both use the same mapping of user and group to an integer.
One user ID, one primary group ID, and up to 16 supplemental group IDs One user ID, one primary group ID, and up to 16 supplemental group IDs
are associated with each RPC request. are associated with each RPC request.
The combination of these identifies the entity on the client The combination of these identifies the entity on the client
that is making the request. that is making the request.
</t> </t>
<t> <t>
A string identifies peers (hosts) in each RPC request. A string identifies peers (hosts) in each RPC request.
<xref target="RFC5531" format="default" sectionFormat="of"/> <xref target="RFC5531" format="default"/>
does not specify any requirements for this string does not specify any requirements for this string
other than that is no longer than 255 octets. other than that it is no longer than 255 octets.
It does not have to be the same from request to request. It does not have to be the same from request to request.
Also, it does not have to match the DNS hostname of the sending host. Also, it does not have to match the DNS hostname of the sending host.
For these reasons, For these reasons,
even though most implementations fill in their hostname in this field, even though most implementations fill in their hostname in this field,
receivers typically ignore its content. receivers typically ignore its content.
</t> </t>
<t> <t>
Appendix A of <xref target="RFC5531" format="default" sectionFormat="of" section="A"/>
<xref target="RFC5531" format="default" sectionFormat="of"/>
contains a brief explanation of security considerations: contains a brief explanation of security considerations:
</t> </t>
<blockquote> <blockquote>
It should be noted that use of this flavor of authentication does not It should be noted that use of this flavor of authentication does not
guarantee any security for the users or providers of a service, in guarantee any security for the users or providers of a service, in
itself. The authentication provided by this scheme can be considered itself. The authentication provided by this scheme can be considered
legitimate only when applications using this scheme and the network legitimate only when applications using this scheme and the network
can be secured externally, and privileged transport addresses are can be secured externally, and privileged transport addresses are
used for the communicating end-points (an example of this is the use used for the communicating end-points (an example of this is the use
of privileged TCP/UDP ports in UNIX systems -- note that not all of privileged TCP/UDP ports in UNIX systems -- note that not all
skipping to change at line 1849 skipping to change at line 1563
other than inclusion of an unprotected domain name. other than inclusion of an unprotected domain name.
</li> </li>
<li> <li>
The use of 32-bit unsigned integers as user and group identifiers The use of 32-bit unsigned integers as user and group identifiers
is problematic because these data types are is problematic because these data types are
not cryptographically signed or otherwise verified by any authority. not cryptographically signed or otherwise verified by any authority.
In addition, the mapping of these integers to users and groups In addition, the mapping of these integers to users and groups
has to be consistent amongst a server and its cohort of clients. has to be consistent amongst a server and its cohort of clients.
</li> </li>
<li> <li>
Because the user and group ID fields are not integrity-protected, Because the user and group ID fields are not integrity protected,
AUTH_SYS does not provide non-repudiation. AUTH_SYS does not provide non-repudiation.
</li> </li>
</ol> </ol>
</section> </section>
<section <section
anchor="section_B08B45C1-1E10-4F7A-935B-1198BAF255C0" anchor="section_B08B45C1-1E10-4F7A-935B-1198BAF255C0"
numbered="true" numbered="true"
removeInRFC="false" removeInRFC="false"
toc="default"> toc="default">
skipping to change at line 1861 skipping to change at line 1575
</li> </li>
</ol> </ol>
</section> </section>
<section <section
anchor="section_B08B45C1-1E10-4F7A-935B-1198BAF255C0" anchor="section_B08B45C1-1E10-4F7A-935B-1198BAF255C0"
numbered="true" numbered="true"
removeInRFC="false" removeInRFC="false"
toc="default"> toc="default">
<name>ASN.1 Module</name> <name>ASN.1 Module</name>
<t> <t>
RFC Editor: In the following section, The following module adheres to ASN.1 specifications <xref target="X.680"/> an
please replace XXX and YYY with the IANA numbers assigned to these new entries. d <xref target="X.690"/>.
And, please remove this Editor's Note
before this document is published.
</t> </t>
<sourcecode name="" type="asn.1" markers="true"> <sourcecode name="" type="asn.1" markers="true">
<![CDATA[ <![CDATA[
RPCwithTLS-2021
{ iso(1) identified-organization(3) dod(6) internet(1)
security(5) mechanisms(5) pkix(7) id-mod(0)
id-mod-rpcWithTLS-2021(105) }
DEFINITIONS IMPLICIT TAGS ::=
BEGIN
-- OID Arc -- OID Arc
id-kp OBJECT IDENTIFIER ::= id-kp OBJECT IDENTIFIER ::=
{ iso(1) identified-organization(3) dod(6) internet(1) { iso(1) identified-organization(3) dod(6) internet(1)
security(5) mechanisms(5) pkix(7) kp(3) } security(5) mechanisms(5) pkix(7) kp(3) }
-- Extended Key Usage Values -- Extended Key Usage Values
id-kp-rpcTLSClient OBJECT IDENTIFIER ::= { id-kp XXX } id-kp-rpcTLSClient OBJECT IDENTIFIER ::= { id-kp 33 }
id-kp-rpcTLSServer OBJECT IDENTIFIER ::= { id-kp YYY } id-kp-rpcTLSServer OBJECT IDENTIFIER ::= { id-kp 34 }
END
]]> ]]>
</sourcecode> </sourcecode>
</section> </section>
<section <section
anchor="section_4959412F-37AD-42B8-9169-D477148F81A8" anchor="section_4959412F-37AD-42B8-9169-D477148F81A8"
numbered="false" numbered="false"
removeInRFC="false" removeInRFC="false"
toc="default"> toc="default">
<name>Acknowledgments</name> <name>Acknowledgments</name>
<t> <t>
Special mention goes to Special mention goes to
<contact fullname="Charles Fisher"/>, <contact fullname="Charles Fisher"/>,
author of author of
<eref target="https://www.linuxjournal.com/content/encrypting-nfsv4-stunnel-tls" <eref target="https://www.linuxjournal.com/content/encrypting-nfsv4-stunnel-tls"
> brackets="angle">
"Encrypting NFSv4 with Stunnel TLS" "Encrypting NFSv4 with Stunnel TLS"</eref>. His article inspired the
</eref>. mechanism described in the current document.
His article inspired the mechanism described in the current document.
</t> </t>
<t> <t>
Many thanks to Many thanks to
<contact fullname="Tigran Mkrtchyan"/>
<contact fullname="Benjamin Coddington"/>,
<contact fullname="Tigran Mkrtchyan"/>,
and and
<contact fullname="Rick Macklem"/> <contact fullname="Rick Macklem"/>
for their work on prototype implementations and feedback on the current document . for their work on prototype implementations and feedback on the current document .
Also, thanks to
<contact fullname="Benjamin Kaduk"/>
for his expert guidance on the use of PKIX and TLS
and to <contact fullname="Russ Housley"/> for his ASN.1 expertise and for provid
ing other proper finishing touches.
In addition, the authors thank the other members of the IESG for
their astute review comments. These contributors made this a significantly bette
r document.
</t> </t>
<t> <t>
Thanks to Thanks to
<contact fullname="Derrell Piper"/> <contact fullname="Derrell Piper"/>
for numerous suggestions that improved both for numerous suggestions that improved both
this simple mechanism this simple mechanism
and and
the current document's security-related discussion. the current document's security-related discussion.
</t> </t>
<t> <t>
Many thanks to Many thanks to
Transport Area Director Transport Area Director
<contact fullname="Magnus Westerlund"/> <contact fullname="Magnus Westerlund"/>
for his sharp questions and careful reading for his sharp questions and careful reading
of the final revisions of the current document. of the final revisions of the current document.
The text of The text of
<xref target="section_B8BF600E-96DC-4C82-AADF-D593826E9B75" format="default" sec tionFormat="of"/> <xref target="section_B8BF600E-96DC-4C82-AADF-D593826E9B75" format="default"/>
is mostly his contribution. is mostly his contribution.
Also, thanks to
<contact fullname="Benjamin Kaduk"/>
for his expert guidance on the use of PKIX and TLS.
In addition,
the authors thank the other members of the IESG for
their astute review comments.
These contributors made this a significantly better document.
</t> </t>
<t> <t>
The authors are additionally grateful to The authors are additionally grateful to
<contact fullname="Bill Baker"/>, <contact fullname="Bill Baker"/>,
<contact fullname="David Black"/>, <contact fullname="David Black"/>,
<contact fullname="Alan DeKok"/>, <contact fullname="Alan DeKok"/>,
<contact fullname="Lars Eggert"/>, <contact fullname="Lars Eggert"/>,
<contact fullname="Olga Kornievskaia"/>, <contact fullname="Olga Kornievskaia"/>,
<contact fullname="Greg Marsden"/>, <contact fullname="Greg Marsden"/>,
<contact fullname="Alex McDonald"/>, <contact fullname="Alex McDonald"/>,
<contact fullname="Justin Mazzola Paluska"/>, <contact fullname="Justin Mazzola Paluska"/>,
<contact fullname="Tom Talpey"/>, <contact fullname="Tom Talpey"/>,
<contact fullname="Martin Thomson"/>, <contact fullname="Martin Thomson"/>,
and and
<contact fullname="Nico Williams"/>, <contact fullname="Nico Williams"/>
for their input and support of this work. for their input and support of this work.
</t> </t>
<t> <t>
Finally, special thanks to Finally, special thanks to
NFSV4 Working Group Chair and document shepherd NFSV4 Working Group Chair and document shepherd
<contact fullname="David Noveck"/>, <contact fullname="David Noveck"/>,
NFSV4 Working Group Chairs NFSV4 Working Group Chairs
<contact fullname="Spencer Shepler"/> <contact fullname="Spencer Shepler"/>
and and <contact fullname="Brian Pawlowski"/>, and NFSV4 Working Group Secretary
<contact fullname="Brian Pawlowski"/>,
and
NFSV4 Working Group Secretary
<contact fullname="Thomas Haynes"/> <contact fullname="Thomas Haynes"/>
for their guidance and oversight. for their guidance and oversight.
</t> </t>
</section> </section>
</back> </back>
</rfc> </rfc>
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