Network Working Group D. Eastlake 3rd

Network Working Group D. Eastlake 3rd
Request for Comments: 4051 Motorola Laboratories
Category: Standards Track April 2005

Additional XML Security Uniform Resource Identifiers (URIs)

Status of This Memo

This document specifies an Internet standards track protocol for the
Internet community, and requests discussion and suggestions for
improvements. Please refer to the current edition of the "Internet
Official Protocol Standards" (STD 1) for the standardization state
and status of this protocol. Distribution of this memo is unlimited.

Copyright Notice

Copyright (C) The Internet Society (2005).

Abstract

A number of Uniform Resource Identifiers (URIs) intended for use with
XML Digital Signatures, Encryption, and Canonicalization are defined.
These URIs identify algorithms and types of keying information.

Table of Contents

1. Introduction.................................................. 2
2. Algorithms.................................................... 3
2.1. DigestMethod Algorithms................................. 3
2.1.1. MD5............................................. 3
2.1.2. SHA-224......................................... 3
2.1.3. SHA-384......................................... 4
2.2. SignatureMethod Message Authentication Code Algorithms.. 4
2.2.1. HMAC-MD5........................................ 4
2.2.2. HMAC SHA Variations............................. 5
2.2.3. HMAC-RIPEMD160.................................. 6
2.3. SignatureMethod Public Key Signature Algorithms......... 6
2.3.1. RSA-MD5......................................... 6
2.3.2. RSA-SHA256...................................... 7
2.3.3. RSA-SHA384...................................... 7
2.3.4. RSA-SHA512...................................... 7
2.3.5. RSA-RIPEMD160................................... 8
2.3.6. ECDSA-SHA*...................................... 8
2.3.7. ESIGN-SHA1...................................... 8
2.4. Minimal Canonicalization................................ 9
2.5. Transform Algorithms.................................... 9
2.5.1. XPointer........................................ 9

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2.6. EncryptionMethod Algorithms............................. 10
2.6.1. ARCFOUR Encryption Algorithm.................... 10
2.6.2. Camellia Block Encryption....................... 10
2.6.3. Camellia Key Wrap............................... 11
2.6.4. PSEC-KEM........................................ 11
3. KeyInfo....................................................... 12
3.1. PKCS #7 Bag of Certificates and CRLs.................... 12
3.2. Additional RetrievalMethod Type Values.................. 12
4. IANA Considerations........................................... 13
5. Security Considerations....................................... 13
Acknowledgements.................................................. 13
Normative References.............................................. 13
Informative References............................................ 15
Author's Address.................................................. 16
Full Copyright Statement.......................................... 17

1. Introduction

XML Digital Signatures, Canonicalization, and Encryption have been
standardized by the W3C and the joint IETF/W3C XMLDSIG working group.
All of these are now W3C Recommendations and IETF Informational or
Standards Track documents. They are available as follows:

IETF level W3C REC Topic
----------- ------- -----
[RFC3275] Draft Std [XMLDSIG] XML Digital Signatures
[RFC3076] Info [CANON] Canonical XML
- - - - - - [XMLENC] XML Encryption
[RFC3741] Info [EXCANON] Exclusive XML Canonicalization

All of these standards and recommendations use URIs [RFC2396] to
identify algorithms and keying information types. This document
provides a convenient reference list of URIs and descriptions for
algorithms in which there is substantial interest, but which cannot
or have not been included in the main documents. Note that raising
XML digital signature to a Draft Standard in the IETF required
removal of any algorithms for which interoperability from the main
standards document has not been demonstrated. This required removal
of the Minimal Canonicalization algorithm, in which there appears to
be a continued interest, to be dropped from the standards track
specification. It is included here.

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 [RFC2119].

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2. Algorithms

The URI [RFC2396] being dropped from the standard because of the
transition from Proposed Standard to Draft Standard is included in
Section 2.4 with its original prefix so as to avoid changing the
XMLDSIG standard's namespace.

http://www.w3.org/2000/09/xmldsig#

Additional algorithms are given URIs that start with:

http://www.w3.org/2001/04/xmldsig-more#

An "xmldsig-more" URI does not imply any official W3C status for
these algorithms or identifiers or that they are only useful in
digital signatures. Currently, dereferencing such URIs may or may
not produce a temporary placeholder document. Permission to use this
URI prefix has been given by the W3C.

2.1. DigestMethod Algorithms

These algorithms are usable wherever a DigestMethod element occurs.

2.1.1. MD5

Identifier:

http://www.w3.org/2001/04/xmldsig-more#md5

The MD5 algorithm [RFC1321] takes no explicit parameters. An example
of an MD5 DigestAlgorithm element is:

<DigestAlgorithm
Algorithm="http://www.w3.org/2001/04/xmldsig-more#md5"/>

An MD5 digest is a 128-bit string. The content of the DigestValue
element shall be the base64 [RFC2405] encoding of this bit string
viewed as a 16-octet octet stream.

2.1.2. SHA-224

Identifier:
http://www.w3.org/2001/04/xmldsig-more#sha224

The SHA-224 algorithm [FIPS-180-2change, RFC3874] takes no explicit
parameters. An example of a SHA-224 DigestAlgorithm element is:

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<DigestAlgorithm
Algorithm="http://www.w3.org/2001/04/xmldsig-more#sha224" />

A SHA-224 digest is a 224 bit string. The content of the DigestValue
element shall be the base64 [RFC2405] encoding of this string viewed
as a 28-octet stream. Because it takes roughly the same amount of
effort to compute a SHA-224 message digest as a SHA-256 digest, and
terseness is usually not a criteria in an XML application,
consideration should be given to the use of SHA-256 as an
alternative.

2.1.3. SHA-384

Identifier:
http://www.w3.org/2001/04/xmldsig-more#sha384

The SHA-384 algorithm [FIPS-180-2] takes no explicit parameters. An
example of a SHA-384 DigestAlgorithm element is:

<DigestAlgorithm
Algorithm="http://www.w3.org/2001/04/xmldsig-more#sha384" />

A SHA-384 digest is a 384 bit string. The content of the DigestValue
element shall be the base64 [RFC2405] encoding of this string viewed
as a 48-octet stream. Because it takes roughly the same amount of
effort to compute a SHA-384 message digest as a SHA-512 digest and
terseness is usually not a criteria in XML application, consideration
should be given to the use of SHA-512 as an alternative.

2.2. SignatureMethod Message Authentication Code Algorithms

Note: Some text in this section is duplicated from [RFC3275] for the
convenience of the reader. RFC 3275 is normative in case of
conflict.

2.2.1. HMAC-MD5

Identifier:
http://www.w3.org/2001/04/xmldsig-more#hmac-md5

The HMAC algorithm [RFC2104] takes the truncation length in bits as a
parameter; if the parameter is not specified then all the bits of the
hash are output. An example of an HMAC-MD5 SignatureMethod element
is as follows:

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<SignatureMethod
Algorithm="http://www.w3.org/2001/04/xmldsig-more#hmac-md5">
<HMACOutputLength>112</HMACOutputLength>
</SignatureMethod>

The output of the HMAC algorithm is ultimately the output (possibly
truncated) of the chosen digest algorithm. This value shall be
base64 [RFC2405] encoded in the same straightforward fashion as the
output of the digest algorithms. For example, the SignatureValue
element for the HMAC-MD5 digest

9294727A 3638BB1C 13F48EF8 158BFC9D

from the test vectors in [RFC2104] would be

kpRyejY4uxwT9I74FYv8nQ==

Schema Definition:

<simpleType name="HMACOutputLength">
<restriction base="integer" />
</simpleType>

DTD:

<!ELEMENT HMACOutputLength (#PCDATA) >

The Schema Definition and DTD immediately shown above are taken from
[RFC3275].

Although some cryptographic suspicions have recently been cast on MD5
for use in signatures such as RSA-MD5 below, this does not effect use
of MD5 in HMAC.

2.2.2. HMAC SHA Variations

Identifiers:
http://www.w3.org/2001/04/xmldsig-more#hmac-sha224
http://www.w3.org/2001/04/xmldsig-more#hmac-sha256
http://www.w3.org/2001/04/xmldsig-more#hmac-sha384
http://www.w3.org/2001/04/xmldsig-more#hmac-sha512

SHA-224, SHA-256, SHA-384, and SHA-512 [FIPS-180-2, FIPS-180-2change,
RFC3874] can also be used in HMAC as described in section 2.2.1 for
HMAC-MD5.

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2.2.3. HMAC-RIPEMD160

Identifier:
http://www.w3.org/2001/04/xmldsig-more#hmac-ripemd160

RIPEMD-160 [RIPEMD-160] can also be used in HMAC as described in
section 2.2.1 for HMAC-MD5.

2.3. SignatureMethod Public Key Signature Algorithms

These algorithms are distinguished from those in Section 2.2 in that
they use public key methods. The verification key is different from
and not feasibly derivable from the signing key.

2.3.1. RSA-MD5

Identifier:
http://www.w3.org/2001/04/xmldsig-more#rsa-md5

RSA-MD5 implies the PKCS#1 v1.5 padding algorithm described in
[RFC3447]. An example of use is

<SignatureMethod
Algorithm="http://www.w3.org/2001/04/xmldsig-more#rsa-md5" />

The SignatureValue content for an RSA-MD5 signature is the base64
[RFC2405] encoding of the octet string computed as per [RFC3447],
section 8.1.1, signature generation for the RSASSA-PKCS1-v1_5
signature scheme. As specified in the EMSA-PKCS1-V1_5-ENCODE
function in [RFC3447, section 9.2.1], the value input to the
signature function MUST contain a pre-pended algorithm object
identifier for the hash function, but the availability of an ASN.1
parser and recognition of OIDs are not required of a signature
verifier. The PKCS#1 v1.5 representation appears as:

CRYPT (PAD (ASN.1 (OID, DIGEST (data))))

Note that the padded ASN.1 will be of the following form:

01 | FF* | 00 | prefix | hash

Vertical bar ("|") represents concatenation. "01", "FF", and "00"
are fixed octets of the corresponding hexadecimal value and the
asterisk ("*") after "FF" indicates repetition. "hash" is the MD5
digest of the data. "prefix" is the ASN.1 BER MD5 algorithm
designator prefix required in PKCS #1 [RFC3447], that is:

hex 30 20 30 0c 06 08 2a 86 48 86 f7 0d 02 05 05 00 04 10

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This prefix is included to facilitate the use of standard
cryptographic libraries. The FF octet MUST be repeated enough times
that the value of the quantity being CRYPTed is exactly one octet
shorter than the RSA modulus.

Due to increases in computer processor power and advances in
cryptography, use of RSA-MD5 is NOT RECOMMENDED.

2.3.2. RSA-SHA256

Identifier:
http://www.w3.org/2001/04/xmldsig-more#rsa-sha256

This implies the PKCS#1 v1.5 padding algorithm [RFC3447] as described
in section 2.3.1, but with the ASN.1 BER SHA-256 algorithm designator
prefix. An example of use is:

<SignatureMethod
Algorithm="http://www.w3.org/2001/04/xmldsig-more#rsa-sha256" />

2.3.3 RSA-SHA384

Identifier:
http://www.w3.org/2001/04/xmldsig-more#rsa-sha384

This implies the PKCS#1 v1.5 padding algorithm [RFC3447] as described
in section 2.3.1, but with the ASN.1 BER SHA-384 algorithm designator
prefix. An example of use is:

<SignatureMethod
Algorithm="http://www.w3.org/2001/04/xmldsig-more#rsa-sha384" />

Because it takes about the same effort to calculate a SHA-384 message
digest as a SHA-512 message digest, it is suggested that RSA-SHA512
be used in preference to RSA-SHA384 where possible.

2.3.4. RSA-SHA512

Identifier:
http://www.w3.org/2001/04/xmldsig-more#rsa-sha512

This implies the PKCS#1 v1.5 padding algorithm [RFC3447] as described
in section 2.3.1, but with the ASN.1 BER SHA-512 algorithm designator
prefix. An example of use is:

<SignatureMethod
Algorithm="http://www.w3.org/2001/04/xmldsig-more#rsa-sha512" />

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2.3.5. RSA-RIPEMD160

Identifier:
http://www.w3.org/2001/04/xmldsig-more/rsa-ripemd160

This implies the PKCS#1 v1.5 padding algorithm [RFC3447], as
described in section 2.3.1, but with the ASN.1 BER RIPEMD160
algorithm designator prefix. An example of use is:

<SignatureMethod
Algorithm="http://www.w3.org/2001/04/xmldsig-more/rsa-ripemd160" />

2.3.6. ECDSA-SHA*

Identifiers
http://www.w3.org/2001/04/xmldsig-more#ecdsa-sha1
http://www.w3.org/2001/04/xmldsig-more#ecdsa-sha224
http://www.w3.org/2001/04/xmldsig-more#ecdsa-sha256
http://www.w3.org/2001/04/xmldsig-more#ecdsa-sha384
http://www.w3.org/2001/04/xmldsig-more#ecdsa-sha512

The Elliptic Curve Digital Signature Algorithm (ECDSA) [FIPS-186-2]
is the elliptic curve analogue of the DSA (DSS) signature method.
For detailed specifications on how to use it with SHA hash functions
and XML Digital Signature, please see [X9.62] and [ECDSA].

2.3.7. ESIGN-SHA1

Identifier
http://www.w3.org/2001/04/xmldsig-more#esign-sha1
http://www.w3.org/2001/04/xmldsig-more#esign-sha224
http://www.w3.org/2001/04/xmldsig-more#esign-sha256
http://www.w3.org/2001/04/xmldsig-more#esign-sha384
http://www.w3.org/2001/04/xmldsig-more#esign-sha512

The ESIGN algorithm specified in [IEEE-P1363a] is a signature scheme
based on the integer factorization problem. It is much faster than
previous digital signature schemes so ESIGN can be implemented on
smart cards without special co-processors.

An example of use is:

<SignatureMethod
Algorithm="http://www.w3.org/2001/04/xmldsig-more#esign-sha1" />

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2.4. Minimal Canonicalization

Thus far two independent interoperable implementations of Minimal
Canonicalization have not been announced. Therefore, when XML
Digital Signature was advanced from Proposed Standard [RFC3075] to
Draft Standard [RFC3275], Minimal Canonicalization was dropped from
the standards track documents. However, there is still interest in
Minimal Canonicalization, indicating its possible future use. For
its definition, see [RFC3075], Section 6.5.1.

For reference, its identifier remains:
http://www.w3.org/2000/09/xmldsig#minimal

2.5. Transform Algorithms

Note that all CanonicalizationMethod algorithms can also be used as
transform algorithms.

2.5.1. XPointer

Identifier:
http://www.w3.org/2001/04/xmldsig-more/xptr

This transform algorithm takes an [XPointer] as an explicit
parameter. An example of use is [RFC3092]:

<Transform
Algorithm="http://www.w3.org/2001/04/xmldsig-more/xptr">
<XPointer
xmlns="http://www.w3.org/2001/04/xmldsig-more/xptr">
xpointer(id("foo")) xmlns(bar=http://foobar.example)
xpointer(//bar:Zab[@Id="foo"])
</XPointer>
</Transform>

Schema Definition:

<element name="XPointer" type="string">

DTD:

<!ELEMENT XPointer (#PCDATA) >

Input to this transform is an octet stream (which is then parsed into
XML).

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Output from this transform is a node set; the results of the XPointer
are processed as defined in the XMLDSIG specification [RFC3275] for a
same document XPointer.

2.6. EncryptionMethod Algorithms

This subsection gives identifiers and information for several
EncryptionMethod Algorithms.

2.6.1. ARCFOUR Encryption Algorithm

Identifier:
http://www.w3.org/2001/04/xmldsig-more#arcfour

ARCFOUR is a fast, simple stream encryption algorithm that is
compatible with RSA Security's RC4 algorithm. An example of the
EncryptionMethod element using ARCFOUR is

<EncryptionMethod
Algorithm="http://www.w3.org/2001/04/xmldsig-more#arcfour">
<KeySize>40</KeySize>
</EncryptionMethod>

Note that Arcfour makes use of the generic KeySize parameter
specified and defined in [XMLENC].

2.6.2. Camellia Block Encryption

Identifiers:
http://www.w3.org/2001/04/xmldsig-more#camellia128-cbc
http://www.w3.org/2001/04/xmldsig-more#camellia192-cbc
http://www.w3.org/2001/04/xmldsig-more#camellia256-cbc

Camellia is an efficient and secure block cipher with the same
interface as the AES [Camellia, RFC3713], that is 128-bit block size
and 128, 192, and 256 bit key sizes. In XML Encryption, Camellia is
used in the same way as the AES: It is used in the Cipher Block
Chaining (CBC) mode with a 128-bit initialization vector (IV). The
resulting cipher text is prefixed by the IV. If included in XML
output, it is then base64 encoded. An example Camellia
EncryptionMethod is as follows:

<EncryptionMethod
Algorithm=
"http://www.w3.org/2001/04/xmldsig-more#camellia128-cbc" />

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2.6.3. Camellia Key Wrap

Identifiers:
http://www.w3.org/2001/04/xmldsig-more#kw-camellia128
http://www.w3.org/2001/04/xmldsig-more#kw-camellia192
http://www.w3.org/2001/04/xmldsig-more#kw-camellia256

The Camellia [Camellia, RFC3713] key wrap is identical to the AES key
wrap algorithm [RFC3394] specified in the XML Encryption standard
with "AES" replaced by "Camellia". As with AES key wrap, the check
value is 0xA6A6A6A6A6A6A6A6.

The algorithm is the same regardless of the size of the Camellia key
used in wrapping (called the key encrypting key or KEK). The
implementation of Camellia is OPTIONAL. However, if it is supported,
the same implementation guidelines of which combinations of KEK size
and wrapped key size should be required to be supported and which are
optional to be supported should be followed as for AES. That is to
say, if Camellia key wrap is supported, then wrapping 128-bit keys
with a 128-bit KEK and wrapping 256-bit keys with a 256-bit KEK are
REQUIRED and all other combinations are OPTIONAL.

An example of use is:

<EncryptionMethod
Algorithm=
"http://www.w3.org/2001/04/xmldsig-more#kw-camellia128" />

2.6.4. PSEC-KEM

Identifier:
http://www.w3.org/2001/04/xmldsig-more#psec-kem

The PSEC-KEM algorithm, specified in [ISO/IEC-18033-2], is a key
encapsulation mechanism using elliptic curve encryption.

An example of use is:

<EncryptionMethod
Algorithm="http://www.w3.org/2001/04/xmlenc#psec-kem">
<ECParameters>
<Version>version</Version>
<FieldID>id</FieldID>
<Curve>curve</Curve>
<Base>base</Base>
<Order>order</Order>
<Cofactor>cofactor</Cofactor>
</ECParameters>

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</EncryptionMethod>

See [ISO/IEC-18033-2] for information on the parameters above.

3. KeyInfo

In section 3.1 a new KeyInfo element child is specified, while in
section 3.2 additional KeyInfo Type values for use in RetrievalMethod
are specified.

3.1. PKCS #7 Bag of Certificates and CRLs

A PKCS #7 [RFC2315] "signedData" can also be used as a bag of
certificates and/or certificate revocation lists (CRLs). The
PKCS7signedData element is defined to accommodate such structures
within KeyInfo. The binary PKCS #7 structure is base64 [RFC2405]
encoded. Any signer information present is ignored. The following
is an example, eliding the base64 data [RFC3092]:

<foo:PKCS7signedData
xmlns:foo="http://www.w3.org/2001/04/xmldsig-more">
...
</foo:PKCS7signedData>

3.2. Additional RetrievalMethod Type Values

The Type attribute of RetrievalMethod is an optional identifier for
the type of data to be retrieved. The result of dereferencing a
RetrievalMethod reference for all KeyInfo types with an XML structure
is an XML element or document with that element as the root. The
various "raw" key information types return a binary value. Thus,
they require a Type attribute because they are not unambiguously
parseable.

Identifiers:
http://www.w3.org/2001/04/xmldsig-more#KeyValue
http://www.w3.org/2001/04/xmldsig-more#RetrievalMethod
http://www.w3.org/2001/04/xmldsig-more#KeyName
http://www.w3.org/2001/04/xmldsig-more#rawX509CRL
http://www.w3.org/2001/04/xmldsig-more#rawPGPKeyPacket
http://www.w3.org/2001/04/xmldsig-more#rawSPKISexp
http://www.w3.org/2001/04/xmldsig-more#PKCS7signedData
http://www.w3.org/2001/04/xmldsig-more#rawPKCS7signedData

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4. IANA Considerations

As it is easy for people to construct their own unique URIs [RFC2396]
and possibly obtain a URI from the W3C if appropriate, it is not
intended that any additional "http://www.w3.org/2001/04/xmldsig-
more#" URIs be created beyond those enumerated in this document.
(W3C Namespace stability rules prohibit the creation of new URIs
under "http://www.w3.org/2000/09/xmldsig#".)

5. Security Considerations

Due to computer speed and cryptographic advances, the use of MD5 as a
DigestMethod and the use of MD5 in the RSA-MD5 SignatureMethod is NOT
RECOMMENDED. The concerned cryptographic advances do not effect the
security of HMAC-MD5; however, there is little reason not to use one
of the SHA series of algorithms.

Acknowledgements

Glenn Adams, Merlin Hughs, Gregor Karlinger, Brian LaMachia, Shiho
Moriai, Joseph Reagle, Russ Housley, and Joel Halpern.

Normative References

[Camellia] "Camellia: A 128-bit Block Cipher Suitable for
Multiple Platforms - Design and Analysis -", K.
Aoki, T. Ichikawa, M. Matsui, S. Moriai, J.
Nakajima, T. Tokita, In Selected Areas in
Cryptography, 7th Annual International Workshop,
SAC 2000, August 2000, Proceedings, Lecture Notes
in Computer Science 2012, pp. 39-56, Springer-
Verlag, 2001.

[ECDSA] Blake-Wilson, S., Karlinger, G., Kobayashi, T.,
and Y. Wang, "Using the Elliptic Curve Signature
Algorithm (ECDSA) for XML Digital Signatures", RFC
4050, April 2005.

[FIPS-180-2] "Secure Hash Standard", (SHA-1/256/384/512) US
Federal Information Processing Standard, 1 August
2002.

[FIPS-180-2change] "FIPS 180-2, Secure Hash Standard Change Notice
1", adds SHA-224 to [FIPS 180-2], 25 February
2004.

[FIPS-186-2] "Digital Signature Standard", National Institute
of Standards and Technology, 2000.

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[IEEE-P1363a] "Standard Specifications for Public Key
Cryptography: Additional Techniques", October
2002.

[ISO/IEC-18033-2] "Information technology -- Security techniques --
Encryption algorithms -- Part 3: Asymmetric
ciphers", CD, October 2002.

[RFC1321] Rivest, R., "The MD5 Message-Digest Algorithm ",
RFC 1321, April 1992.

[RFC2104] Krawczyk, H., Bellare, M., and R. Canetti, "HMAC:
Keyed-Hashing for Message Authentication", RFC
2104, February 1997.

[RFC2119] Bradner, S., "Key words for use in RFCs to
Indicate Requirement Levels", BCP 14, RFC 2119,
March 1997.

[RFC2396] Berners-Lee, T., Fielding, R., and L. Masinter,
"Uniform Resource Identifiers (URI): Generic
Syntax", RFC 2396, August 1998.

[RFC2405] Madson, C. and N. Doraswamy, "The ESP DES-CBC
Cipher Algorithm With Explicit IV", RFC 2405,
November 1998.

[RFC2315] Kaliski, B., "PKCS #7: Cryptographic Message
Syntax Version 1.5", RFC 2315, March 1998.

[RFC3075] Eastlake 3rd, D., Reagle, J., and D. Solo, "XML-
Signature Syntax and Processing", RFC 3075, March
2001. (RFC 3075 was obsoleted by RFC 3275 but is
referenced in this document for its description of
Minimal Canonicalization which was dropped in RFC
3275.)

[RFC3275] Eastlake 3rd, D., Reagle, J., and D. Solo,
"(Extensible Markup Language) XML-Signature Syntax
and Processing", RFC 3275, March 2002.

[RFC3394] Schaad, J. and R. Housley, "Advanced Encryption
Standard (AES) Key Wrap Algorithm", RFC 3394,
September 2002.

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[RFC3447] Jonsson, J. and B. Kaliski, "Public-Key
Cryptography Standards (PKCS) #1: RSA Cryptography
Specifications Version 2.1", RFC 3447, February
2003.

[RFC3713] Matsui, M., Nakajima, J., and S. Moriai, "A
Description of the Camellia Encryption Algorithm",
RFC 3713, April 2004.

[RFC3874] Housley, R., "A 224-bit One-way Hash Function:
SHA-224", RFC 3874, September 2004.

[RIPEMD-160] ISO/IEC 10118-3:1998, "Information Technology -
Security techniques - Hash-functions - Part3:
Dedicated hash- functions", ISO, 1998.

[X9.62] X9.62-200X, "Public Key Cryptography for the
Financial Services Industry: The Elliptic Curve
Digital Signature Algorithm (ECDSA)", Accredited
Standards Committee X9, American National
Standards Institute.

[XMLDSIG] "XML-Signature Syntax and Processing", D. Eastlake
3rd, J. Reagle, & D. Solo, 12 February 2002.
<http://www.w3.org/TR/xmldsig-core/>

[XMLENC] "XML Encryption Syntax and Processing", J. Reagle,
D. Eastlake, December 2002.
<http://www.w3.org/TR/2001/RED-xmlenc-core-
20021210/>

[XPointer] "XML Pointer Language (XPointer) Version 1.0", W3C
working draft, Steve DeRose, Eve Maler, Ron Daniel
Jr., January 2001.
<http://www.w3.org/TR/2001/WD-xptr-20010108>

Informative References

[CANON] "Canonical XML Version 1.0", John Boyer.
<http://www.w3.org/TR/2001/REC-xml-c14n-20010315>.

[EXCANON] "Exclusive XML Canonicalization Version 1.0", D.
Eastlake, J. Reagle, 18 July 2002.
<http://www.w3.org/TR/REC-xml-enc-c14n-20020718/>.

[RFC3076] Boyer, J., "Canonical XML Version 1.0", RFC 3076,
March 2001.

Eastlake 3rd Standards Track [Page 15]

RFC 4051 Additional XML Security URIs April 2005

[RFC3092] Eastlake 3rd, D., Manros, C., and E. Raymond,
"Etymology of "Foo"", RFC 3092, 2001.

[RFC3741] Boyer, J., Eastlake 3rd, D., and J. Reagle,
"Exclusive XML Canonicalization, Version 1.0", RFC
3741, March 2004.

Author's Address

Donald E. Eastlake 3rd
Motorola Laboratories
155 Beaver Street
Milford, MA 01757 USA

Phone: +1-508-786-7554 (w)
+1-508-634-2066 (h)
EMail: [email protected]

Eastlake 3rd Standards Track [Page 16]

RFC 4051 Additional XML Security URIs April 2005

Full Copyright Statement

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Eastlake 3rd Standards Track [Page 17]