Quantum-Safe Hybrid (QSH) Ciphersuite for Transport Layer Security (TLS) version 1.3
draft-whyte-qsh-tls13-03
The information below is for an old version of the document.
| Document | Type |
This is an older version of an Internet-Draft whose latest revision state is "Expired".
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|---|---|---|---|
| Authors | John M. Schanck , William Whyte , Zhenfei Zhang | ||
| Last updated | 2016-10-05 | ||
| RFC stream | (None) | ||
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| Stream | Stream state | (No stream defined) | |
| Consensus boilerplate | Unknown | ||
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draft-whyte-qsh-tls13-03
INTERNET-DRAFT J. M. Schanck
Intended Status: Experimental Security Innovation & U. Waterloo
Expires: 2017-04-04 W. Whyte
Security Innovation
Z. Zhang
Security Innovation
2016-10-04
Quantum-Safe Hybrid (QSH) Ciphersuite
for Transport Layer Security (TLS) version 1.3
draft-whyte-qsh-tls13-03.txt
Abstract
This document describes the Quantum-Safe Hybrid ciphersuite, a new
cipher suite providing modular design for quantum-safe cryptography
to be adopted in the handshake for the Transport Layer Security (TLS)
protocol version 1.3. In particular, it specifies the use of the
NTRUEncrypt encryption scheme in a TLS handshake.
Status of This Memo
This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF), its areas, and its working groups. Note that
other groups may also distribute working documents as Internet-
Drafts.
The list of current Internet-Drafts can be accessed at
http://www.ietf.org/1id-abstracts.html.
The list of Internet-Draft Shadow Directories can be accessed at
http://www.ietf.org/shadow.html.
Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress."
This Internet-Draft will expire on 2017-04-04.
Update from last version: keeping alive till TLS WG review.
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3
2. Modular design for quantum-safe hybrid handshake . . . . . . . 4
3. Data Structures and Computations . . . . . . . . . . . . . . . 7
3.1. Data structures for Quantum-safe Crypto Schemes . . . . . 7
3.2. Client Hello Extensions . . . . . . . . . . . . . . . . . 9
3.3. HelloRetryRequest Extensions . . . . . . . . . . . . . . . 11
3.4. Server Key Share Extension . . . . . . . . . . . . . . . . 12
4. Cipher Suites . . . . . . . . . . . . . . . . . . . . . . . . 14
5. Specific information for Quantum Safe Scheme . . . . . . . . . 14
5.1. NTRUEncrypt . . . . . . . . . . . . . . . . . . . . . . . 14
5.2. LWE . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
5.3. HFE . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
5.4. McEliece/McBits . . . . . . . . . . . . . . . . . . . . . 15
6. Security Considerations . . . . . . . . . . . . . . . . . . . 15
6.1. Security, Authenticity and Forward Secrecy . . . . . . . . 15
6.2. Quantum Security and Quantum Forward Secrecy . . . . . . . 15
6.3. Quantum Authenticity . . . . . . . . . . . . . . . . . . . 15
7. Compatibility with TLS 1.2 and earlier version . . . . . . . . 15
8. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 15
9. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 16
10. References . . . . . . . . . . . . . . . . . . . . . . . . . 16
10.1. Normative References . . . . . . . . . . . . . . . . . . 16
10.2. Informative References . . . . . . . . . . . . . . . . . 17
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 18
Copyright Notice . . . . . . . . . . . . . . . . . . . . . . . . . 18
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1. Introduction
Quantum computers pose a significant threat to modern cryptography.
Two most widely adopted public key cryptosystems, namely, RSA [PKCS1]
and Elliptic Curve Cryptography (ECC) [SECG], will be broken by
general purpose quantum computers. RSA is adopted in TLS from
Version 1.0 and to TLS Version 1.3 [RFC2246], [RFC4346], [RFC5246],
[TLS1.3]. ECC is enabled in RFC 4492 [RFC4492] and adopted in TLS
version 1.2 [RFC5246] and version 1.3 [TLS1.3]. On the other hand,
there exist several quantum-safe cryptosystems, such as the
NTRUEncrypt cryptosystem [EESS1], that deliver similar performance,
yet are conjectured to be robust against quantum computers.
This document describes a modular design that allows one or many
quantum-safe cryptosystems to be adopted in the handshake protocol,
applicable to TLS Version 1.3 [TLS1.3]. It uses a hybrid approach
that combines a classical handshake mechanism with key encapsulation
mechanisms instantiated with quantum-safe encryption schemes. The
modular design provides quantum-safe features to TLS 1.3 without any
introduction of extra cipher suites. Yet, it allows the flexibility
to include new and advanced quantum-safe encryption schemes at
present and in the future.
Extensions to TLS 1.2 [RFC5246] and earlier versions can be found in
[QSH12].
The remainder of this document is organized as follows. Section 2
provides an overview of the modular design of quantum-safe handshake
for TLS 1.3. Section 3 specifies various data structures needed for
a quantum safe handshake, their encoding in TLS messages, and the
processing of those messages. Section 4 defines new TLS_QSH cipher
suites. Section 5 provides specific information for quantum safe
encryption schemes. Section 6 discusses security considerations.
Section 7 discusses compatibility with other versions of TLS.
Section 8 describes IANA considerations for the name spaces created
by this document. Section 9 gives acknowledgements.
This is followed by the lists of normative and informative references
cited in this document, the authors' contact information, and
statements on intellectual property rights and copyrights.
Implementation of this specification requires familiarity with TLS
[RFC2246], [RFC4346], [RFC5246], [TLS1.3], TLS extensions [RFC4366],
and knowledge of the corresponding quantum-safe cryptosystem.
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in RFC 2119 [RFC2119].
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Well-known abbreviations and acronyms can be found at RFC Editor
Abbreviations List [REAL].
2. Modular design for quantum-safe hybrid handshake
This document introduces a modular approach to including new quantum-
safe key exchange algorithms within TLS 1.3, while maintaining the
assurance that comes from the use of already established cipher
suites. It allows the TLS premaster secret to be agreed using both
an established classical cipher suite and a quantum-safe key
encapsulation mechanism.
Client Server
ClientHello
ClientKeyShare -------->
<-------- HelloRetryRequest
ClientHello
ClientKeyShare -------->
ServerHello
ServerKeyShare
{EncryptedExtensions*}
{Certificate*}
{CertificateRequest*+}
{CertificateVerify*}
<-------- {Finished}
{Certificate*+}
{CertificateVerify*+}
{Finished} -------->
[Application Data] <-------> [Application Data]
* message is not sent under some conditions
+ message is not sent unless client authentication
is desired
Figure 1: Message flow in a full TLS 1.3 handshake
Figure 1 shows all messages involved in the TLS key establishment
protocol (aka full handshake). The addition of quantum-safe
cryptography has direct impact only on the ClientHello, the
HelloRetryRequest, and the ServerKeyShare messages. In the rest of
this document, we describe each quantum-safe key exchange data
structure in greater detail in terms of the content and processing of
these messages.
The authentication is provided by classical cryptography. The
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introduction of quantum-safe encryption schemes delivers forward
secrecy against quantum attackers. The additional cryptographic data
exchanged between the client and the server is shown in Figure 2 and
3.
Figure 2 illustrates the data flow of a zero round trip quantum-safe
handshake for TLS. This handshake is proceeded when 1) the classical
key exchange is also zero round trip, and 2) the server supports the
QSH schemes from QSHPKList.
Client Server
ClientHelloExtension
+ qshDataExtension
(QSHPKList)
+ qshNegotiateExtension
(QSHSchemeIDList) -------->
EncryptedExtensions*
+ qshDataExtension
(QSHCipherList)
<-------- {Finished}
{Finished} -------->
ClassicSecret|QSHSecret <-------> ClassicSecret|QSHSecret
* previously known as SeverKeyShareExtensions
+ additional data
Figure 2: Additional cryptographic data
for a zero round trip TLS handshake
In the case that the server does not support the QSH schemes from
QSHPKList, the server will reply with a HelloRetryRequest, which
results into a full handshake.
Client Server
ClientHelloExtensions
+ qshDataExtension
(QSHPKList)
+ qshNegotiateExtension
(QSHSchemeIDList) -------->
HelloRetryRequestExtensions
+ qshNegotiateExtension
<-------- (AcceptQSHSchemeIDList)
ClientHelloExtensions
+ qshDataExtension
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(QSHPKList) -------->
EncryptedExtensions*
+ qshDataExtension
(QSHCipherList)
<-------- {Finished}
{Finished} -------->
ClassicSecret|QSHSecret <-------> ClassicSecret|QSHSecret
* previously known as SeverKeyShareExtensions
+ additional data
Figure 3: Additional cryptographic data
for a full TLS handshake
As usual, the ClientHello message includes the list of classical
cipher suites the client wishes to negotiate (e.g.,
TLS_ECDH_ECDSA_WITH_NULL_SHA). In addition there will be two
potential extension fields, indicating qshData and qshNegotiate
extensions.
The ClientHelloExtension field MUST have qshData extension field:
o QSHPKList: a list of distinct public keys for QSH Scheme
from the client, each public key for a distinct
quantum safe encryption scheme supported by the
client.
The ClientHelloExtension field MAY have qshNegotiate extension
field:
o QSHSchemeIDList:
a list of distinct QSHSchemeIDs from the client,
each ID represents a quantum safe encryption
scheme/parameter set supported by the client
QSHSchemeIDList must not list the scheme IDs whose public key is
already included in the QSHPKList.
If the server supports QSH schemes/parameter sets for the public keys
received from QSHPKList, the server will proceed the zero round trip
handshake, provided that the zero round trip is also permitted by
classical handshake. If not, the server will pick a (list of)
QSHSchemeID(s) from the QSHSchemeIDList to form the
AcceptQSHSchemeIDList, and request public keys for those schemes in a
HelloRetryRequest message. If the server does not support any of the
QSH schemes from either QSHPKList or QSHSchemeIDList, the server will
abort the handshake.
The extension field of the HelloRetryRequest message MUST have an
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qshNegotiate extension field:
o AcceptQSHSchemeIDList:
a list of distinct QSHSchemeIDs from the server,
each ID represents a quantum safe encryption
scheme/parameter set supported/selected by the server
The ServerKeyShare message contains an indication of the classical
cipher suite selected, and the ServerKeyShare material appropriate to
that cipher suite. Additionally, the ServerKeyShareExtension (a.k.a.
EncryptedExtension) field message MUST contain a qshData extension
field listing ciphertexts:
o QSHCipherList:
a list of ciphertests
[Encrypt_QSHPK1(QSHS1)]|[Encrypt_QSHPK2(QSHS2)]|...
where the QSH secret keying material is
QSHSecret = QSHS1|QSHS2|..., and QSHPKi is from
QSHPKList.
The final premaster secret negotiated by the client and the server is
the concatenation of the classical premaster secret, QSHSecret,
QSHPK1|QSHPK2|... in that order. A 48 bytes fixed length master
secret is derived from the premaster secret at the end of the
handshake, using a pseudo random function specified by the classical
cipher suite (see Section 8.1. RFC 5246 [RFC5246]).
3. Data Structures and Computations
This section specifies the data structures and computations used by
TLS_QSH cipher suite specified in Sections 2. The presentation
language used here is the same as that used in TLS v1.3 [TLS1.3].
Since this specification extends TLS, these descriptions should be
merged with those in the TLS specification and any others that extend
TLS. This means that enum types may not specify all possible values,
and structures with multiple formats chosen with a select() clause
may not indicate all possible cases.
3.1. Data structures for Quantum-safe Crypto Schemes
enum {
ntru_eess443 (0x0101),
ntru_eess587 (0x0102),
ntru_eess743 (0x0103),
reserved (0x0102..0x01FF),
lwe_XXX (0x0201),
reserved (0x0202..0x02FF),
hfe_XXX (0x0301),
reserved (0x0302..0x03FF),
mcbits_XXX (0x0401),
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reserved (0x0402..0x04FF),
reserved (0x0500..0xFEFF),
(0xFFFF)
} QSHSchemeID;
ntru_eess443, etc: Indicates parameter set to be used for the
NTRUEncrypt encryption scheme. The name of the parameter sets
defined here are those specified in [EESS1].
lwe_XXX, etc: Indicates parameters for Learning With Error (LWE)
encryption scheme. The name of the parameters defined here are
not specified in this document.
hfe_XXX, etc: Indicates parameters for Hidden Field Equotion (HFE)
encryption scheme. The name of the parameters defined here are
not specified in this document.
mcbits_XXX, etc: Indicates parameters for McEliece encryption
scheme instantiated with McBits parameter set. The name of the
parameters defined here are not specified in this document.
See Section 5 for specific information for quantum safe scheme.
The QSHSchemes name space is maintained by IANA [IANA]. See Section
8 for information on how new schemes are added.
The server implementation SHOULD support all of the above QSHSchemes,
and client implementation SHALL support at least one of them.
struct {
QSHSchemeID id<1..2^16-1>
} QSHIDList;
The QSHSchemeIDList and AcceptQSHSchemeIDList are two instances of
QSHIDList structure. This structure defines a list of QSHSchemeIDs,
each representing a quantum safe encryption scheme.
struct {
QSHSchemeID id,
opaque pubKey<1..2^16-1>
} QSHPK;
struct {
QSHPK keys<1..2^24-1>
} QSHPKList;
The structure of public keys send from the client to the server,
namely, QSHPK, has two fields: QSHSchemeID specifies the
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corresponding quantum safe encryption scheme, and an opaque encodes
the actual public key data following the specification of the
corresponding quantum safe encryption scheme. Any entity that
reserves a new quantum safe encryption scheme identifier MUST specify
how the keys and ciphertexts for that scheme are encoded. See
Section 5 for definitions of the encodings of the schemes specified
in this document.
NOTE: the QSHPK is a opaque of up to (2^24-1) bytes. This may exceed
the size limitation of extensions (2^16-1).
The QSHPKList is a list of QSHPKs.
struct {
QSHSchemeID id,
opaque encryptedKey<1..2^16-1>
} QSHCipher;
struct {
QSHCipher encryptedKeys<1..2^24-1>
} QSHCipherList;
The structure of ciphertext send from the server to the client,
namely QSHCipher, has two fields: QSHSchemeID specifies the
corresponding quantum safe encryption scheme, and an opaque encodes
the actual ciphertext following the specification of the
corresponding quantum safe encryption scheme.
The QSHCipherList is a list of ciphertexts.
3.2. Client Hello Extensions
This section specifies a TLS extension that can be included with the
ClientHello message as described in RFC 4366 [RFC4366].
NOTE: To support larger QSH quantum-safe cryptosystems it may be
necessary to raise the maximum size of an extension to 2^24-1 octets.
When these extensions are sent:
When a client wish to negotiate a handshake using TLS_QSH approach,
the extensions MUST be sent along with the first ClientHello message.
Follow-up ClientHello message MAY also use these extensions when a
zero round trip handshake failed.
Meaning of these extensions:
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qshNegotiate extension allows a client to send a QSHSchemeIDList that
enumerates QSHSchemeIDs for supported quantum safe cryptosystems.
qshData extension allows a client to send a QSHPKList of public keys
for quantum-safe encryption schemes.
Note: QSHSchemeID MUST be distinct in QSHSchemeIDList. If
qshNegotiate extension and qshData extension are both send within a
same ClientHello extension, QSHSchemeIDList must not enumerate
QSHschemeIDs whose public keys are already in QSHPKList.
Structure of the extensions:
The general structure of TLS extensions is described in [RFC4366],
and this specification adds a new type to ExtensionType.
enum {
qshNegotiate(0x18)
qshData(0x19)
} ExtensionType;
qshNegotiate (Supported TLS_QSH Extension): Indicates the list of
QSHSchemeIDs supported by the client. For this extension, the
opaque extension_data field MAY contain QSHSchemeIDList and its
field can be NULL.
qshData (Supported TLS_QSH Extension): Indicates the list of
QSHScheme public keys supported by the client. For this
extension, the opaque extension_data field MUST contain QSHPKList
and its field is not NULL.
struct {
select (ExtensionType) {
case qshNegotiate:
QSHSchemeIDList qshSchemeIDList,
case qshData:
QSHPKList qshPKList,
}
} ClientHelloExtension;
Items in both qshPKList and qshSchemeIDList are ordered according to
the client's preferences (favorite choice first).
As an example, a client that only supports ntru_eess439 (0x0101) and
ntru_eess593 (0x0102) and prefers to use ntru_eess439 would encode
its qshSchemeIDList as follows:
04 01 01 01 02
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An example of a qshNegotiate extension field will therefore look as
follows:
00 18 | extension length | 00 04 01 01 01 02 | ...
Note: the extension type value appearing in these examples is
tentative.
Actions of the sender:
If the ClientHello message starts a fresh handshake, a client that
proposes TLS_QSH approach in its ClientHello message appends both
qshNegotiate and qshData extensions (along with any others),
enumerating the supported quantum-safe crypto systems that the client
wish to use to negotiate keys with the server.
If the ClientHello message is in response to a HelloRetryRequest, the
client appends qshData extension (along with any others), enumerating
the QSHScheme public keys supported by the server.
Actions of the receiver:
A server that receives a ClientHello with a TLS_QSH approach MUST
check the extension field to use the client's enumerated capabilities
to guide its selection of appropriate quantum safe encryption
algorithms. The TLS_QSH approach must be negotiated only if the
server can successfully complete the handshake while using the listed
quantum-safe cryptosystems from the client.
The server will carry out a classic handshake with the client using a
classical cipher suite indicated by the ClientHello message. If the
server supports QSHSchemes of public keys included in the qshData
extension, the server will include a QSHCipherList in the
EncryptedExtension field of ServerKeyShare message; if not, the
server will select a (list of) supported QSHScheme(s), indexed by
QSHSchemeID(s), and form the AcceptQSHSchemeIDList with its selected
schemes. This list will be send back to the client via the extension
field of HelloRetryRequest.
If a server does not understand the Extension, does not understand
the list of quantum-safe encryption schemes, or is unable to complete
the TLS_QSH handshake while restricting itself to the enumerated
cryptosystems, it MUST NOT negotiate the use of a TLS_QSH approach.
Depending on what other cipher suites are proposed by the client and
supported by the server, this may result in a fatal handshake failure
alert due to the lack of common cipher suites.
3.3. HelloRetryRequest Extensions
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This section specifies a TLS extension that can be included with the
HelloRetryRequest message as described in [TLS1.3].
When this extension is sent:
The server will send this message in response to a ClientHello
message where the extension fields contains a extension type quantum-
safe-hybrid, when it was able to find an acceptable set of QSHSchemes
from qshNegotiate but not from qshData. If it cannot find such a
match, it will respond with a handshake failure alert.
Meaning of this extension:
This extension allows a server to notify the client the ID(s) for the
quantum-safe encryption scheme(s) it chooses from the
QSHSchemeIDList.
Structure of this extension:
struct {
select (ExtensionType) {
case qshNegotiate:
QSHSchemeIDList acceptQSHSchemeIDList,
}
} HelloRetryRequestExtension;
Actions of the sender:
The server selects a number of QSHSchemeIDs in response to a
ClientHelloExtension message. The selection is based on client's
preference. The QSHSchemeIDs selected MUST exist in the received
QSHSchemeIDList. The server form the acceptQSHSchemeIDList with the
list of selected QSHSchemeIDs.
Actions of the receiver:
A client that receives a HelloRetryRequest message containing an
extension type qshNegotiate will extract the agreed QSHSchemeIDs and
from the acceptQSHSchemeIDList. Those QSHSchemeIDs will be used when
the client generates another ClientHello message.
3.4. Server Key Share Extension
[[This may be later on changed into *EncryptedExtensions* let's see
how TLS 1.3 will define it]]
NOTE: To support larger QSH quantum-safe cryptosystems it may be
necessary to raise the maximum size of an extension to 2^24-1 octets.
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When this message is sent:
The server will include this extension field in response to a
ClientHello message with extension type qshData.
Meaning of this message:
It is used to send QSH key material (encrypted by one or many of the
client's public keys) to the client.
Structure of this message:
The TLS ServerKeyShareExtension field is extended as follows.
struct {
select (ExtensionType) {
case qshData:
QSHCipherList encryptedQSHSecret,
}
} ServerKeyShare;
Actions of the sender:
The server extracts client's public keys QSHPK1, ..., QSHPKn from the
qshData field in the received Client Hello extensions. For each of
the public keys QSHPKi, generates a secret QSHSi. The length in
bytes of QSHSi MUST be the lesser of (a) 48, the length of the
classical master secret, and (b) the maximum plaintext input length
for the corresponding encryption scheme (see Section 5).
The server then encrypts the QSHSi with QSHPKi, and form the
encryptedQSHSecret with those ciphertexts.
The QSH keying material is:
QSHSecret = QSHS1|QSHS2|...|QSHSk
The server will finally form the premaster secret as a concatenation
of the classical premaster secret (negotiated via classical exchange,
i.e., Key Share messages), QHSSecret, and QSHPK (the public keys that
encrypts the message). A 48 bytes fixed length master secret is
derived from the premaster secret at the end of the handshake, using
a pseudo random function specified by the classical cipher suite (see
Section 8.1. RFC 5246 [RFC5246]).
Actions of the receiver:
The client processes the ServerKeyShareExtension
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by decrypting each ciphertext in encryptedQSHSecret using the
client's secret key and obtaining QSHSecret.
The client will finally form the premaster secret as a concatenation
of the classical premaster secret (negotiated via classical exchange,
i.e., Key Share messages), QHSSecret, and QSHPK (the public keys that
encrypts the message). A 48 bytes fixed length master secret is
derived from the premaster secret at the end of the handshake, using
a pseudo random function specified by the classical cipher suite (see
Section 8.1. RFC 5246 [RFC5246]).
4. Cipher Suites
The TLS_QSH approach does not introduce any additional cipher suite
identifiers.
5. Specific information for Quantum Safe Scheme
Selection criteria for qauntum-safe cryptography to be used in this
TLS_QSH approach can be found at [QSHPKC]. Also see [PQCRY] for
initial recommendations of quantum safe cryptography from EU's
PQCRYPTO project.
5.1. NTRUEncrypt
NTRUEncrypt parameter sets are identified by the values ntru_eess443
(0x0101), ntru_eess587 (0x0102), ntru_eess743 (0x0103) assigned in
this document.
For each of these parameter sets, the public key and ciphertext are
Ring Elements as defined in [EESS1]. The encoded public key and
ciphertext are the result of encoding the relevant Ring Element with
RE2BSP as defined in [EESS1].
For each parameter set the the maximum plaintext input length in
bytes is as follows. This is used when determining the length of the
client/server-generated secrets CliSi and SerSi as specified in
sections 3.4 and 3.5.
eess443 49
eess587 76
eess743 106
5.2. LWE
Encoding not defined in this document.
5.3. HFE
Encoding not defined in this document.
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5.4. McEliece/McBits
Encoding not defined in this document.
6. Security Considerations
6.1. Security, Authenticity and Forward Secrecy
Security, authenticity and forward secrecy against classical
computers are inherent from classical handshake mechanism.
6.2. Quantum Security and Quantum Forward Secrecy
The proposed handshake mechanism provides quantum security and
quantum forward secrecy.
Quantum resistant feature of QSHSchemes ensures a quantum attacker
will not learn QSH keying material S. A quantum attacker may learn
classic handshake information. Given an input X, the leftover hash
lemma [LHL] ensures that one can extract Y bits that are almost
uniformly distributed, where Y is asymptotic to the min-entropy of X.
An adversary who has some partial knowledge about X, will have almost
no knowledge about Y. This guarantees the attacker will not learn
the final premaster secret so long as S has enough entropy and
remains secret. This also guarantees the premaster secret is secure
even if the client's and/or the server's long term keys are
compromised.
6.3. Quantum Authenticity
The proposed approach relies on the classical cipher suite for
authenticity. Thus, an attacker with quantum computing capability
will be able to break the authenticity.
7. Compatibility with TLS 1.2 and earlier version
Compatibility with TLS 1.2 and earlier version can be found in
[QSH12].
8. IANA Considerations
This document describes a new name spaces for use with the TLS
protocol:
o QSHSchemeID
Any additional assignments require IETF Consensus action [RFC2434].
Process for determining whether a public key algorithm is in fact
quantum-safe, and therefore entitled to a QSHSchemeId, is not
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specified in this document and may be established by the TLS working
group as it sees fit. For example, TLS WG may require that
algorithms are vetted in some sense by CFRG or have been published in
a standard by a recognized international standards body such as IEEE
or ANSI X9.
9. Acknowledgements
Funding for the RFC Editor function is provided by the IETF
Administrative Support Activity (IASA).
We wish to thank Douglas Stebila, [[[names]]] for helpful
discussions.
10. References
10.1. Normative References
[EESS1] Consortium for Efficient Embedded Security, "Efficient
Embedded Security standards (EESS) #1", March 2015,
<https://github.com/NTRUOpenSourceProject/ntru-
crypto/blob/master/doc/EESS1-2015v3.0.pdf/>.
[FIPS180] NIST, "Secure Hash Standard", FIPS 180-2, 2002.
[FIPS186] NIST, "Digital Signature Standard", FIPS 186-2, 2000.
[H2020] Lange, T., "PQCRYPTO project in the EU", April, 2015.
<http://pqcrypto.eu.org/slides/20150403.pdf>
[HOF15] Hoffstein, J., Pipher, J., Schanck, J., Silverman, J.,
Whyte, W., and Zhang, Z., "Choosing Parameters for
NTRUEncrypt", 2015. <https://eprint.iacr.org/2015/708>
[LIN11] Lindner, R., and Peikert, C., "Better Key Sizes (and
Attacks) for LWE-Based Encryption", 2011.
[LHL] Impagliazzo, R., Levin, L., and Luby, M., "Pseudo-random
generation from one-way functions", 1989.
[MCBIT] Bernstein, D., Chou, T., and Schwabe, P., "McBits: Fast
Constant-Time Code- Based Cryptography", 2013.
[MCELI] McEliece, R., "A Public-Key Cryptosystem Based On
Algebraic Coding Theory", 1978.
[PKCS1] RSA Laboratories, "PKCS#1: RSA Encryption Standard version
1.5", PKCS 1, November 1993
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[PQCRY] PQCRYPTO, "Initial recommendations of long-term secure
post-quantum systems".
<http://pqcrypto.eu.org/docs/initial-recommendations.pdf>
[QSH12] Schanck, J., Whyte, W., and Zhang, Z., "Quantum-Safe
Hybrid (QSH) Ciphersuite for Transport Layer Security
(TLS) version 1.2", draft-whyte-qsh-tls12-00, July 2015.
[QSHPKC] Schanck, J., Whyte, W., and Zhang, Z., "Criteria for
selection of public-key cryptographic algorithms for
quantum-safe hybrid cryptography", draft-whyte-select-pkc-
qsh-00.txt, Sep 2015.
[REAL] "RFC Editor Abbreviations List", September 2013,
<https://www.rfc-editor.org/rfc-style-
guide/abbrev.expansion.txt/>.
[RFC2119] Bradner, S., "Key Words for Use in RFCs to Indicate
Requirement Levels", RFC 2119, March 1997.
[RFC2246] Dierks, T. and C. Allen, "The TLS Protocol Version 1.0",
RFC 2246, January 1999.
[RFC2434] Narten, T. and H. Alvestrand, "Guidelines for Writing an
IANA Considerations Section in RFCs", RFC 2434, October
1998.
[RFC4346] Dierks, T. and E. Rescorla, "The Transport Layer Security
(TLS) Protocol Version 1.1", RFC 4346, April 2006.
[RFC4366] Blake-Wilson, S., Nysrom, M., Hopwood, D., Mikkelsen, J.,
and T. Wright, "Transport Layer Security (TLS)
Extensions", RFC 4366, April 2006.
[RFC4492] Blake-Wilson, S., Bolyard, N., Gupta, V., Hawk, C., and B.
Moeller, "Elliptic Curve Cryptography (ECC) Cipher Suites
for Transport Layer Security (TLS)", RFC 4492, May 2006.
[RFC5246] Dierks, T. and E. Rescorla, "The Transport Layer Security
(TLS) Protocol Version 1.2", RFC 5246, August 2008.
[TLS1.3] E. Rescorla, "The Transport Layer Security (TLS) Protocol
Version 1.3", draft-ietf-tls-tls13-05, March 2015.
10.2. Informative References
[RFC5990] Randall, J., Kaliski, B., Brainard, J. and Turner S., "Use
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of the RSA-KEM Key Transport Algorithm in the
Cryptographic Message Syntax (CMS)", RFC 5990, September
2010.
[RFC5859] Krawczyk, H., Eronen, P., "HMAC-based Extract-and-Expand
Key Derivation Function (HKDF)", RFC 5859, May 2010.
Authors' Addresses
John M. Schanck
Security Innovation, US
and
University of Waterloo, Canada
jschanck@securityinnovation.com
William Whyte
Security Innovation, US
wwhyte@securityinnovation.com
Zhenfei Zhang
Security Innovation, US
zzhang@securityinnovation.com
Copyright Notice
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2: Copyright (c) 2015 IETF Trust and the persons identified as the
document authors. All rights reserved.
IETF Trust Legal Provisions of 28-dec-2009, Section 6.b(ii),
paragraph 3: This document is subject to BCP 78 and the IETF Trust's
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to this document.
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