draft-ietf-tls-oob-pubkey-04.txt   draft-ietf-tls-oob-pubkey-05.txt 
TLS P. Wouters TLS P. Wouters, Ed.
Internet-Draft Red Hat Internet-Draft Red Hat
Intended status: Standards Track J. Gilmore Intended status: Standards Track H. Tschofenig, Ed.
Expires: January 17, 2013 Expires: April 25, 2013 Nokia Siemens Networks
J. Gilmore
S. Weiler S. Weiler
SPARTA, Inc. SPARTA, Inc.
T. Kivinen T. Kivinen
AuthenTec AuthenTec
H. Tschofenig October 22, 2012
Nokia Siemens Networks
July 16, 2012
Out-of-Band Public Key Validation for Transport Layer Security Out-of-Band Public Key Validation for Transport Layer Security (TLS)
draft-ietf-tls-oob-pubkey-04.txt draft-ietf-tls-oob-pubkey-05.txt
Abstract Abstract
This document specifies a new certificate type for exchanging raw This document specifies a new certificate type for exchanging raw
public keys in Transport Layer Security (TLS) and Datagram Transport public keys in Transport Layer Security (TLS) and Datagram Transport
Layer Security (DTLS) for use with out-of-band public key validation. Layer Security (DTLS) for use with out-of-band public key validation.
Currently, TLS authentication can only occur via X.509-based Public Currently, TLS authentication can only occur via X.509-based Public
Key Infrastructure (PKI) or OpenPGP certificates. By specifying a Key Infrastructure (PKI) or OpenPGP certificates. By specifying a
minimum resource for raw public key exchange, implementations can use minimum resource for raw public key exchange, implementations can use
alternative public key validation methods. alternative public key validation methods.
skipping to change at page 2, line 6 skipping to change at page 2, line 6
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This Internet-Draft will expire on January 17, 2013. This Internet-Draft will expire on April 25, 2013.
Copyright Notice Copyright Notice
Copyright (c) 2012 IETF Trust and the persons identified as the Copyright (c) 2012 IETF Trust and the persons identified as the
document authors. All rights reserved. document authors. All rights reserved.
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Table of Contents Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 4 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 4
2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 4 2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 4
3. New TLS Extensions . . . . . . . . . . . . . . . . . . . . . . 4 3. New TLS Extension . . . . . . . . . . . . . . . . . . . . . . 4
4. TLS Handshake Extension . . . . . . . . . . . . . . . . . . . 5 4. TLS Handshake Extension . . . . . . . . . . . . . . . . . . . 7
4.1. Client Hello . . . . . . . . . . . . . . . . . . . . . . . 5 4.1. Client Hello . . . . . . . . . . . . . . . . . . . . . . . 7
4.2. Server Hello . . . . . . . . . . . . . . . . . . . . . . . 6 4.2. Server Hello . . . . . . . . . . . . . . . . . . . . . . . 7
4.3. Certificate Request . . . . . . . . . . . . . . . . . . . 6 4.3. Certificate Request . . . . . . . . . . . . . . . . . . . 8
4.4. Certificate Payload . . . . . . . . . . . . . . . . . . . 6 4.4. Other Handshake Messages . . . . . . . . . . . . . . . . . 8
4.5. Other TLS Messages . . . . . . . . . . . . . . . . . . . . 6 4.5. Client authentication . . . . . . . . . . . . . . . . . . 8
5. Examples . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 5. Examples . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
6. Security Considerations . . . . . . . . . . . . . . . . . . . 9 6. Security Considerations . . . . . . . . . . . . . . . . . . . 11
7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 10 7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 12
8. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 10 8. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 12
9. References . . . . . . . . . . . . . . . . . . . . . . . . . . 11 9. References . . . . . . . . . . . . . . . . . . . . . . . . . . 13
9.1. Normative References . . . . . . . . . . . . . . . . . . . 11 9.1. Normative References . . . . . . . . . . . . . . . . . . . 13
9.2. Informative References . . . . . . . . . . . . . . . . . . 11 9.2. Informative References . . . . . . . . . . . . . . . . . . 13
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 12 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 14
1. Introduction 1. Introduction
Traditionally, TLS server public keys are obtained in PKIX containers Traditionally, TLS server public keys are obtained in PKIX containers
in-band using the TLS handshake and validated using trust anchors in-band using the TLS handshake and validated using trust anchors
based on a [PKIX] certification authority (CA). This method can add based on a [PKIX] certification authority (CA). This method can add
a complicated trust relationship that is difficult to validate. a complicated trust relationship that is difficult to validate.
Examples of such complexity can be seen in [Defeating-SSL]. Examples of such complexity can be seen in [Defeating-SSL].
Alternative methods are available that allow a TLS client to obtain Alternative methods are available that allow a TLS client to obtain
the TLS server public key: the TLS server public key:
o The TLS server public key is obtained from a DNSSEC secured o The TLS server public key is obtained from a DNSSEC secured
resource records using DANE [I-D.ietf-dane-protocol]. resource records using DANE [RFC6698].
o The TLS server public key is obtained from a [PKIX] certificate o The TLS server public key is obtained from a [PKIX] certificate
chain from an Lightweight Directory Access Protocol (LDAP) [LDAP] chain from an Lightweight Directory Access Protocol (LDAP) [LDAP]
server. server.
o The TLS client and server public key is provisioned into the o The TLS client and server public key is provisioned into the
operating system firmware image, and updated via software updates. operating system firmware image, and updated via software updates.
Some smart objects use the UDP-based Constrained Application Protocol Some smart objects use the UDP-based Constrained Application Protocol
(CoAP) [I-D.ietf-core-coap] to interact with a Web server to upload (CoAP) [I-D.ietf-core-coap] to interact with a Web server to upload
sensor data at a regular intervals, such as temperature readings. sensor data at a regular intervals, such as temperature readings.
CoAP [I-D.ietf-core-coap] can utilize DTLS for securing the client- CoAP [I-D.ietf-core-coap] can utilize DTLS for securing the client-
to-server communication. As part of the manufacturing process, the to-server communication. As part of the manufacturing process, the
embeded device may be configured with the address and the public key embeded device may be configured with the address and the public key
of a dedicated CoAP server, as well as a public key for the client of a dedicated CoAP server, as well as a public key for the client
itself. The usage of X.509-based PKIX certificates [PKIX] does not itself. The usage of X.509-based PKIX certificates [PKIX] may not
suit all smart object deployments and would therefore be an suit all smart object deployments and would therefore be an
unneccesarry burden. unneccesarry burden.
The Transport Layer Security (TLS) Protocol Version 1.2 [RFC5246] The Transport Layer Security (TLS) Protocol Version 1.2 [RFC5246]
provides a framework for extensions to TLS as well as guidelines for provides a framework for extensions to TLS as well as guidelines for
designing such extensions. This document defines an extension to designing such extensions. This document defines an extension to
indicate the support for raw public keys. indicate the support for raw public keys.
2. Terminology 2. Terminology
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in RFC 2119 [RFC2119]. document are to be interpreted as described in RFC 2119 [RFC2119].
3. New TLS Extensions 3. New TLS Extension
In order to indicate the support for multiple certificate types two This section describes the changes to the TLS handshake message
new extensions are defined by this specification with the following contents when raw public key certificates are to be used. Figure 3
semantic: illustrates the exchange of messages as described in the sub-sections
below. The client and the server exchange the newly defined
certificate_type extension to indicate their ability and desire to
exchange raw public keys. These raw public keys, in the form of a
SubjectPublicKeyInfo structure, are then carried inside the
certificate payload. The SubjectPublicKeyInfo structure is defined
in Section 4.1 of RFC 5280. Note that the SubjectPublicKeyInfo block
does not only contain the raw keys, such as the public exponent and
the modulus of an RSA public key, but also an algorithm identifier.
The structure, as shown in Figure 1, is encoded in an ASN.1 format
and therefore contains length information as well.
cert-send: The certificate payload in this message contains a SubjectPublicKeyInfo ::= SEQUENCE {
certificate of the type indicated by this extension. algorithm AlgorithmIdentifier,
subjectPublicKey BIT STRING }
cert-receive: By including this extension an entity indicates that Figure 1: SubjectPublicKeyInfo ASN.1 Structure.
it is able to recieve and process the indicated certificate types.
This list is sorted by preference.
enum { X.509(0), RawPublicKey(1), (255) } CertType; The algorithm identifiers are Object Identifiers (OIDs). RFC 3279
[RFC3279], for example, defines the following OIDs shown in Figure 2.
CertType cert-receive <1..2^8-1>; Key Type | Document | OID
-----------------------+----------------------------+-------------------
RSA | Section 2.3.1 of RFC 3279 | 1.2.840.113549.1.1
.......................|............................|...................
Digital Signature | |
Algorithm (DSS) | Section 2.3.2 of RFC 3279 | 1.2.840.10040.4.1
.......................|............................|...................
Elliptic Curve | |
Digital Signature | |
Algorithm (ECDSA) | Section 2.3.5 of RFC 3279 | 1.2.840.10045.2.1
-----------------------+----------------------------+-------------------
CertType cert-send; Figure 2: Example Algorithm Identifiers.
Figure 1: New TLS Extension Structures client_hello,
certificate_type ->
No new cipher suites are required for use with raw public keys. All <- server_hello,
existing cipher suites that support a key exchange method compatible certificate_type,
with the key in the certificate can be used in combination with raw certificate,
public key certificate types. server_key_exchange,
certificate_request,
server_hello_done
certificate,
client_key_exchange,
certificate_verify,
change_cipher_spec,
finished ->
4. TLS Handshake Extension <- change_cipher_spec,
finished
This section describes the semantic of the 'cert-send' and the 'cert- Application Data <-------> Application Data
receive' extensions for the different handshake messages.
4.1. Client Hello Figure 3: Basic Raw Public Key TLS Exchange.
To allow a TLS client to indicate that it is able to receive a The "certificate_type" TLS extension carries a list of supported
certificate of a specific type it MAY include the 'cert-receive' certificate types the client can send and receive, sorted by client
extension in the client hello message. To indicate the ability to preference. Two values are defined for each certificate types to
process a raw public key by the server the TLS client MUST include differentiate whether a client or a server is able to process a
the 'cert-receive' with the value one (1) (indicating "RawPublicKey") certificate of a specific type or can also send it. This extension
in the list of supported certificate types. If a TLS client only MUST be omitted if the client only supports X.509 certificates. The
supports X.509 certificates it MAY include this extension to indicate "extension_data" field of this extension contains a CertTypeExtension
support for it. structure.
Future documents may define additional certificate types that require Note that the CertTypeExtension structure is being used both by the
addition values to be registered. client and the server, even though the structure is only specified
once in this document.
Note: No new cipher suites are required to use raw public keys. All The structure of the CertTypeExtension is defined as follows:
enum { client, server } ClientOrServerExtension;
enum { X.509-Accept (0),
X.509-Offer (1),
RawPublicKey-Accept (2),
RawPublicKey-Offer (3),
(255)
} CertificateType;
struct {
select(ClientOrServerExtension)
case client:
CertificateType certificate_types<1..2^8-1>;
case server:
CertificateType certificate_type;
}
} CertTypeExtension;
Figure 4: CertTypeExtension Structure.
No new cipher suites are required to use raw public keys. All
existing cipher suites that support a key exchange method compatible existing cipher suites that support a key exchange method compatible
with the defined extension can be used. with the defined extension can be used.
4.2. Server Hello 4. TLS Handshake Extension
If the server receives a client hello that contains the 'cert- 4.1. Client Hello
receive' extension then two outcomes are possible. The server MUST
either select a certificate type from client-provided list or
terminate the session with a fatal alert of type
"unsupported_certificate". In the former case the procedure in
Section 4.4 MUST be followed.
4.3. Certificate Request In order to indicate the support of out-of-band raw public keys,
clients MUST include an extension of type "certificate_type" to the
extended client hello message. The "certificate_type" TLS extension
is assigned the value of [TBD] from the TLS ExtensionType registry.
This value is used as the extension number for the extensions in both
the client hello message and the server hello message. The hello
extension mechanism is described in TLS 1.2 [RFC5246].
The Certificate Request payload sent by the TLS server to the TLS 4.2. Server Hello
client MUST be accompanied by a 'cert-receive' extension, which
indicates to the TLS client the certificate type the server supports.
4.4. Certificate Payload If the server receives a client hello that contains the
"certificate_type" extension and chooses a cipher suite then two
outcomes are possible. The server MUST either select a certificate
type from the CertificateType field in the extended client hello or
terminate the session with a fatal alert of type
"unsupported_certificate".
Certificate payloads MUST be accompanied by a 'cert-send' extension, The certificate type selected by the server is encoded in a
which indicates the certificate format found in the Certificate CertTypeExtension structure, which is included in the extended server
payload itself. hello message using an extension of type "certificate_type". Servers
that only support X.509 certificates MAY omit including the
"certificate_type" extension in the extended server hello.
The list of supported certificate types to choose from MUST have been If the client supports the receiption of raw public keys and the
obtained via the 'cert-receive' extension. This ensures that a server is able to provide such a raw public key then the TLS server
Certificate payload only contains a certificate type that is also MUST place the SubjectPublicKeyInfo structure into the Certificate
supported by the recipient. payload. The public key MUST match the selected key exchange
algorithm.
When the 'RawPublicKey' certificate type is selected then the 4.3. Certificate Request
SubjectPublicKeyInfo structure MUST be placed into the Certificate
payload. The type of the asymmetric key MUST match the selected key
exchange algorithm.
4.5. Other TLS Messages The semantics of this message remain the same as in the TLS
specification.
4.4. Other Handshake Messages
All the other handshake messages are identical to the TLS All the other handshake messages are identical to the TLS
specification. specification.
4.5. Client authentication
Client authentication by the TLS server is supported only through
authentication of the received client SubjectPublicKeyInfo via an
out-of-band method
5. Examples 5. Examples
Figure 2, Figure 3, and Figure 4 illustrate example message Figure 5, Figure 6, and Figure 7 illustrate example message
exchanges. exchanges.
The first example shows an exchange where the TLS client indicates The first example shows an exchange where the TLS client indicates
its ability to process two certificate types, namely raw public keys its ability to process two certificate types, namely raw public keys
and X.509 certificates via the 'cert-receive' extension (see [1]). and X.509 certificates via the 'certificate_type' extension in [1].
When the TLS server receives the client hello it processes the cert- When the TLS server receives the client hello it processes the
receive extension and since it also has a raw public key it indicates certificate_type extension and since it also has a raw public key it
in [2] that it had choosen to place the SubjectPublicKeyInfo indicates in [2] that it had choosen to place the
structure into the Certificate payload (see [3]). The client uses SubjectPublicKeyInfo structure into the Certificate payload (see
this raw public key in the TLS handshake and an out-of-band [3]). The client uses this raw public key in the TLS handshake and
technique, such as DANE, to verify its validatity. an out-of-band technique, such as DANE, to verify its validatity.
client_hello, client_hello,
cert-receive=(RawPublicKey, X.509) -> // [1] certificate_type=(RawPublicKey-Accept) -> // [1]
<- server_hello, <- server_hello,
cert-send=RawPublicKey, // [2] certificate_type=(RawPublicKey-Offer), // [2]
certificate, // [3] certificate, // [3]
server_key_exchange, server_key_exchange,
server_hello_done server_hello_done
client_key_exchange, client_key_exchange,
change_cipher_spec, change_cipher_spec,
finished -> finished ->
<- change_cipher_spec, <- change_cipher_spec,
finished finished
Application Data <-------> Application Data Application Data <-------> Application Data
Figure 2: Example with Raw Public Key provided by the TLS Server Figure 5: Example with Raw Public Key provided by the TLS Server
In our second example the TLS client and the TLS server use raw In our second example both the TLS client and the TLS server use raw
public keys. This is a use case envisioned for smart object public keys. This is a use case envisioned for smart object
networking. The TLS client in this case is an embedded device that networking. The TLS client in this case is an embedded device that
only supports raw public keys and therefore it indicates this only supports raw public keys and therefore it indicates this
capability via the 'cert-receive' extension in [1]. As in the capability via the 'certificate_type' extension in [1]. As in the
previously shown example the server fulfills the client's request and previously shown example the server fulfills the client's request and
provides a raw public key into the Certificate payload back to the provides a raw public key into the Certificate payload back to the
client (see [2] and [3]). The TLS server, however, demands client client (see [3]). The TLS server, however, demands client
authentication and for this reason a Certificate_Request payload is authentication and therefore a certificate_request is added [4]. The
added [4], which comes with an indication of the supported certificate_type payload indicates the TLS server supported
certificate types by the server, see [5]. The TLS client, who has a certificate types, see [2], and particularly that the TLS server is
raw public key pre-provisioned, returns it in the Certificate payload also able to process raw public keys sent by the client. The TLS
[7] to the server with the indication about its content [6]. client, who has a raw public key pre-provisioned, returns it in the
Certificate payload [5] to the server.
client_hello, client_hello,
cert-receive=(RawPublicKey) -> // [1] certificate_type=(RawPublicKey-Offer, RawPublicKey-Accept) -> // [1]
<- server_hello, <- server_hello,
cert-send=RawPublicKey,// [2] certificate_type=(RawPublicKey-Offer,
certificate, // [3] RawPublicKey-Accept) // [2]
certificate_request, // [4] certificate, // [3]
cert-receive=(RawPublicKey, X.509) // [5] certificate_request, // [4]
server_key_exchange, server_key_exchange,
server_hello_done server_hello_done
cert-send=RawPublicKey, // [6] certificate, // [5]
certificate, // [7] client_key_exchange,
client_key_exchange, change_cipher_spec,
change_cipher_spec, finished ->
finished ->
<- change_cipher_spec, <- change_cipher_spec,
finished finished
Application Data <-------> Application Data Application Data <-------> Application Data
Figure 3: Example with Raw Public Key provided by the TLS Server and Figure 6: Example with Raw Public Key provided by the TLS Server and
the Client the Client
In our last example we illustrate a combination of raw public key and In our last example we illustrate a combination of raw public key and
X.509 usage. The client uses a raw public key for client X.509 usage. The client uses a raw public key for client
authentication but the server provides an X.509 certificate. This authentication but the server provides an X.509 certificate. This
exchange starts with the client indicating its ability to process exchange starts with the client indicating its ability to process
X.509 certificates. The server provides the X.509 certificate using X.509 certificates provided by the server, and the ability to send
raw public keys. The server provides the X.509 certificate using
that format in [3] with the indication present in [2]. For client that format in [3] with the indication present in [2]. For client
authentication, however, the server indicates in [5] that it is able authentication, however, the server indicates in [2] that it is able
to support raw public keys as well as X.509 certificates. The TLS to support raw public keys. The TLS client provides a raw public key
client provides a raw public key in [7] and the indication in [6]. in [5] after receiving and processing the TLS server hello message.
client_hello,
cert-receive=(X.509) -> // [1]
<- server_hello, client_hello,
cert-send=X.509,// [2] certificate_type=(X.509 Receive, RawPublicKey-Offer) -> // [1]
certificate, // [3]
certificate_request, // [4]
cert-receive=(RawPublicKey, X.509) // [5]
server_key_exchange,
server_hello_done
cert-send=RawPublicKey, // [6] <- server_hello,
certificate, // [7] certificate_type=(X.509 Send,
client_key_exchange, RawPublicKey-Accept), // [2]
change_cipher_spec, certificate, // [3]
finished -> certificate_request, // [4]
server_key_exchange,
server_hello_done
certificate, // [5]
client_key_exchange,
change_cipher_spec,
finished ->
<- change_cipher_spec, <- change_cipher_spec,
finished finished
Application Data <-------> Application Data Application Data <-------> Application Data
Figure 4: Hybrid Certificate Example Figure 7: Hybrid Certificate Example
6. Security Considerations 6. Security Considerations
The transmission of raw public keys, as described in this document, The transmission of raw public keys, as described in this document,
provides benefits by lowering the over-the-air transmission overhead provides benefits by lowering the over-the-air transmission overhead
since raw public keys are quite naturally smaller than an entire since raw public keys are quite naturally smaller than an entire
certificate. There are also advantages from a codesize point of view certificate. There are also advantages from a codesize point of view
for parsing and processing these keys. The crytographic procedures for parsing and processing these keys. The crytographic procedures
for assocating the public key with the possession of a private key for assocating the public key with the possession of a private key
also follows standard procedures. also follows standard procedures.
The main security challenge is, however, how to associate the public The main security challenge is, however, how to associate the public
key with a specific entity. This information will be needed to make key with a specific entity. This information will be needed to make
authorization decisions. Without a secure binding, man-in-the-middle authorization decisions. Without a secure binding, man-in-the-middle
attacks may be the consequence. This document assumes that such attacks may be the consequence. This document assumes that such
binding can be made out-of-band and we list a few examples in binding can be made out-of-band and we list a few examples in
Section 1. DANE [I-D.ietf-dane-protocol] offers one such approach. Section 1. DANE [RFC6698] offers one such approach. If public keys
If public keys are obtained using DANE, these public keys are are obtained using DANE, these public keys are authenticated via
authenticated via DNSSEC. Pre-configured keys is another out of band DNSSEC. Pre-configured keys is another out of band method for
method for authenticating raw public keys. While pre-configured keys authenticating raw public keys. While pre-configured keys are not
are not suitable for a generic Web-based e-commerce environment such suitable for a generic Web-based e-commerce environment such keys are
keys are a reasonable approach for many smart object deployments a reasonable approach for many smart object deployments where there
where there is a close relationship between the software running on is a close relationship between the software running on the device
the device and the server-side communication endpoint. Regardless of and the server-side communication endpoint. Regardless of the chosen
the chosen mechanism for out-of-band public key validation an mechanism for out-of-band public key validation an assessment of the
assessment of the most suitable approach has to be made prior to the most suitable approach has to be made prior to the start of a
start of a deployment to ensure the security of the system. deployment to ensure the security of the system.
7. IANA Considerations 7. IANA Considerations
This document defines two new TLS extension, 'cert-send' and 'cert- This document defines a new TLS extension, "certificate_type",
receive', and their values need to be added to the TLS ExtensionType assigned a value of [TBD] from the TLS ExtensionType registry defined
registry created by RFC 5246 [RFC5246]. in [RFC5246]. This value is used as the extension number for the
extensions in both the client hello message and the server hello
message. The new extension type is used for certificate type
negotiation.
The values in these new extensions contains an 8-bit CertificateType The "certificate_type" extension contains an 8-bit CertificateType
field, for which a new registry, named "Certificate Types", is field, for which a new registry, named "TLS Certificate Types", is
established in this document, to be maintained by IANA. The registry established in this document, to be maintained by IANA. The registry
is segmented in the following way: is segmented in the following way:
1. The value (0) is defined in this document. 1. The values 0 - 3 are defined in Figure 4.
2. Values from 2 through 223 decimal inclusive are assigned using 2. Values from 3 through 223 decimal inclusive are assigned via IETF
the 'Specification Required' policy defined in RFC 5226 Consensus [RFC5226].
[RFC5226].
3. Values from 224 decimal through 255 decimal inclusive are 3. Values from 224 decimal through 255 decimal inclusive are
reserved for 'Private Use', see [RFC5226]. reserved for Private Use [RFC5226].
8. Acknowledgements 8. Acknowledgements
The feedback from the TLS working group meeting at IETF#81 has The feedback from the TLS working group meeting at IETF#81 has
substantially shaped the document and we would like to thank the substantially shaped the document and we would like to thank the
meeting participants for their input. The support for hashes of meeting participants for their input. The support for hashes of
public keys has been moved to [I-D.ietf-tls-cached-info] after the public keys has been moved to [I-D.ietf-tls-cached-info] after the
discussions at the IETF#82 meeting and the feedback from Eric discussions at the IETF#82 meeting and the feedback from Eric
Rescorla. Rescorla.
We would like to thank the following persons for their review We would like to thank the following persons for their review
comments: Martin Rex, Bill Frantz, Zach Shelby, Carsten Bormann, comments: Martin Rex, Bill Frantz, Zach Shelby, Carsten Bormann,
Cullen Jennings, Rene Struik, Alper Yegin, Jim Schaad, Paul Hoffman, Cullen Jennings, Rene Struik, Alper Yegin, Jim Schaad, Paul Hoffman,
Robert Cragie, Nikos Mavrogiannopoulos, Phil Hunt, John Bradley, and Robert Cragie, Nikos Mavrogiannopoulos, Phil Hunt, John Bradley,
James Manger. Klaus Hartke, Stefan Jucker, and James Manger.
9. References 9. References
9.1. Normative References 9.1. Normative References
[PKIX] Cooper, D., Santesson, S., Farrell, S., Boeyen, S., [PKIX] Cooper, D., Santesson, S., Farrell, S., Boeyen, S.,
Housley, R., and W. Polk, "Internet X.509 Public Key Housley, R., and W. Polk, "Internet X.509 Public Key
Infrastructure Certificate and Certificate Revocation List Infrastructure Certificate and Certificate Revocation List
(CRL) Profile", RFC 5280, May 2008. (CRL) Profile", RFC 5280, May 2008.
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
skipping to change at page 11, line 28 skipping to change at page 13, line 28
[Defeating-SSL] [Defeating-SSL]
Marlinspike, M., "New Tricks for Defeating SSL in Marlinspike, M., "New Tricks for Defeating SSL in
Practice", February 2009, <http://www.blackhat.com/ Practice", February 2009, <http://www.blackhat.com/
presentations/bh-dc-09/Marlinspike/ presentations/bh-dc-09/Marlinspike/
BlackHat-DC-09-Marlinspike-Defeating-SSL.pdf>. BlackHat-DC-09-Marlinspike-Defeating-SSL.pdf>.
[I-D.ietf-core-coap] [I-D.ietf-core-coap]
Shelby, Z., Hartke, K., Bormann, C., and B. Frank, Shelby, Z., Hartke, K., Bormann, C., and B. Frank,
"Constrained Application Protocol (CoAP)", "Constrained Application Protocol (CoAP)",
draft-ietf-core-coap-10 (work in progress), June 2012. draft-ietf-core-coap-12 (work in progress), October 2012.
[I-D.ietf-dane-protocol]
Hoffman, P. and J. Schlyter, "The DNS-Based Authentication
of Named Entities (DANE) Transport Layer Security (TLS)
Protocol: TLSA", draft-ietf-dane-protocol-23 (work in
progress), June 2012.
[I-D.ietf-tls-cached-info] [I-D.ietf-tls-cached-info]
Santesson, S. and H. Tschofenig, "Transport Layer Security Santesson, S. and H. Tschofenig, "Transport Layer Security
(TLS) Cached Information Extension", (TLS) Cached Information Extension",
draft-ietf-tls-cached-info-11 (work in progress), draft-ietf-tls-cached-info-13 (work in progress),
December 2011. September 2012.
[LDAP] Sermersheim, J., "Lightweight Directory Access Protocol [LDAP] Sermersheim, J., "Lightweight Directory Access Protocol
(LDAP): The Protocol", RFC 4511, June 2006. (LDAP): The Protocol", RFC 4511, June 2006.
[RFC3279] Bassham, L., Polk, W., and R. Housley, "Algorithms and
Identifiers for the Internet X.509 Public Key
Infrastructure Certificate and Certificate Revocation List
(CRL) Profile", RFC 3279, April 2002.
[RFC5226] Narten, T. and H. Alvestrand, "Guidelines for Writing an [RFC5226] Narten, T. and H. Alvestrand, "Guidelines for Writing an
IANA Considerations Section in RFCs", BCP 26, RFC 5226, IANA Considerations Section in RFCs", BCP 26, RFC 5226,
May 2008. May 2008.
[RFC6091] Mavrogiannopoulos, N. and D. Gillmor, "Using OpenPGP Keys [RFC6698] Hoffman, P. and J. Schlyter, "The DNS-Based Authentication
for Transport Layer Security (TLS) Authentication", of Named Entities (DANE) Transport Layer Security (TLS)
RFC 6091, February 2011. Protocol: TLSA", RFC 6698, August 2012.
Authors' Addresses Authors' Addresses
Paul Wouters Paul Wouters (editor)
Red Hat Red Hat
Email: paul@nohats.ca Email: paul@nohats.ca
Hannes Tschofenig (editor)
Nokia Siemens Networks
Linnoitustie 6
Espoo 02600
Finland
Phone: +358 (50) 4871445
Email: Hannes.Tschofenig@gmx.net
URI: http://www.tschofenig.priv.at
John Gilmore John Gilmore
PO Box 170608 PO Box 170608
San Francisco, California 94117 San Francisco, California 94117
USA USA
Phone: +1 415 221 6524 Phone: +1 415 221 6524
Email: gnu@toad.com Email: gnu@toad.com
URI: https://www.toad.com/ URI: https://www.toad.com/
Samuel Weiler Samuel Weiler
skipping to change at page 12, line 36 skipping to change at line 541
Email: weiler@tislabs.com Email: weiler@tislabs.com
Tero Kivinen Tero Kivinen
AuthenTec AuthenTec
Eerikinkatu 28 Eerikinkatu 28
HELSINKI FI-00180 HELSINKI FI-00180
FI FI
Email: kivinen@iki.fi Email: kivinen@iki.fi
Hannes Tschofenig
Nokia Siemens Networks
Linnoitustie 6
Espoo 02600
Finland
Phone: +358 (50) 4871445
Email: Hannes.Tschofenig@gmx.net
URI: http://www.tschofenig.priv.at
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