From 1d73af0bc1f264147ad16e94b7d58d03844146e8 Mon Sep 17 00:00:00 2001 From: Dirk Meyer Date: Mon, 8 Sep 2008 19:29:23 +0000 Subject: [PATCH] Change KeyInfo element from W3C XML Signature to ASCII git-svn-id: file:///home/ksmith/gitmigration/svn/xmpp/trunk@2227 4b5297f7-1745-476d-ba37-a9c6900126ab --- xep-0189.xml | 333 ++++++++++++++++++++++++++++----------------------- 1 file changed, 184 insertions(+), 149 deletions(-) diff --git a/xep-0189.xml b/xep-0189.xml index 4a8f04f9..759f256b 100644 --- a/xep-0189.xml +++ b/xep-0189.xml @@ -17,13 +17,30 @@ XMPP Core XEP-0060 XEP-0163 - W3C XML Signature None None NOT YET ASSIGNED &ianpaterson; &stpeter; + + Dirk + Meyer + dmeyer@tzi.de + dmeyer@jabber.org + + + 0.8 + 2008-09-08 + dm +

Change KeyInfo element from W3C XML Signature to ASCII

 + + + 0.7 + 2008-03-03 + psa +

Changed temporary namespace per XEP-0053 procedures; corrected several small errors in the text and examples.

 + 0.7 2008-03-03 @@ -72,10 +89,87 @@

An entity MAY have multiple public keys with different formats, signatures, algorithms, strengths and expiry dates. Each client used by a user may use different keys.

+ +

This document does not use the 'http://www.w3.org/2000/09/xmldsig#' namespace as specified in &w3xmlsig; because it is too complicated and the complexity is not needed for this use case. The keyinfo element defined in the 'urn:xmpp:tmp:pubkey' namespace is based on the ASCII output most cryptographic libraries support. The keyinfo has three parts: a unique name, the public key data (optional) and signatures from other keys (optional). The name is the fingerprint of the public key. The unique name / fingerprint can be used to search for a key (see Public Key Publication via PEP) and MUST be written in lower case.

+ +

Since X.509 has no standard fingerprint mechanisms, the SHA1 value in hex of the certificate is used as name. The public key data is the X.509 certificate in DER encoding. To be included in an XML stream the data is Base64 encoded.

+ + 428b1358a286430f628da23fb33ddaf6e474f5c5 + + MIICCTCCAXKgAwIBAgIJALhU0Id6xxwQMA0GCSqGSIb3DQEBBQUAMA4xDDAKBgNV + BAMTA2ZvbzAeFw0wNzEyMjgyMDA1MTRaFw0wODEyMjcyMDA1MTRaMA4xDDAKBgNV + BAMTA2ZvbzCBnzANBgkqhkiG9w0BAQEFAAOBjQAwgYkCgYEA0DPcfeJzKWLGE22p + RMINLKr+CxqozF14DqkXkLUwGzTqYRi49yK6aebZ9ssFspTTjqa2uNpw1U32748t + qU6bpACWHbcC+eZ/hm5KymXBhL3Vjfb/dW0xrtxjI9JRFgrgWAyxndlNZUpN2s3D + hKDfVgpPSx/Zp8d/ubbARxqZZZkCAwEAAaNvMG0wHQYDVR0OBBYEFJWwFqmSRGcx + YXmQfdF+XBWkeML4MD4GA1UdIwQ3MDWAFJWwFqmSRGcxYXmQfdF+XBWkeML4oRKk + EDAOMQwwCgYDVQQDEwNmb2+CCQC4VNCHesccEDAMBgNVHRMEBTADAQH/MA0GCSqG + SIb3DQEBBQUAA4GBAIhlUeGZ0d0msNVxYWAXg2lRsJt9INHJQTCJMmoUeTtaRjyp + ffJtuopguNNBDn+MjrEp2/+zLNMahDYLXaTVmBf6zvY0hzB9Ih0kNTh23Fb5j+yK + QChPXQUo0EGCaODWhfhKRNdseUozfNWOz9iTgMGw8eYNLllQRL//iAOfOr/8 + + + ]]> + + +

OpenPGP (&rfc4880;) defines how to create fingerprints. This fingerprint is used as unique name. The public key data is the OpenPGP public key using binary output. Like X.509 certificates the data must be Base64 encoded to fit in an XML stream.

+ + 89d099a3428481cc63fe3fa44e7df2d002b4ce44 + + mQGiBDsKPy8RBACG1vVC8+5jMbtr8YUSfL2ciIu/Zb7/dDhwFd4iFlH7BIEt3RjR + wmiCUw/pcL8LHav7L2L4/Yxm8peJxyK0c11tP5Mq8kG3v55BSkZzn3fwKilEYG1c + rkOPWMEHds3c8kLDn+WNyxrSpw10EyJSsXc0edBdl7eLHiNQsCNmPpZhvwCg8uCQ + ... + HDU4Qg9lslDyfa2pHqkweHvC/LmIxrZeCSxOgSMLV8bqbbra1n3F4vdqgc8VP8I2 + o9wBSf3HMohGBBgRAgAGBQI7Cj82AAoJEE598tACtM5EuWIAn0tHJF+Bk7pPAngp + hFOdFgS8UBSAAJ9ZPviS2XDzrWRpiyKV+hDqO/WTHA== + + + ]]> + + +

Besides the name and the data a key can have one or more signatures. A signature can be used to sign an X.509 certificate with an OpenPGP key or the other way around. This makes it possible to verify a self-signed X.509 certificate with the OpenPGP web-of-trust. A second use case is the concept of user and client keys. A user may choose to use a different X.509 certificate for each client for &xep0178; or &xep0250;. All these client key can be signed by a user key. Once the user key is known all clients can be verified. This XMPP based approach makes it possible to use self-signed certificates without setting up a CA.

+

The signature has an issuer and the signature data. The issuer contains the unique name / fingerprint of the key that was used to create the signature. An optional argument 'jid' SHOULD be set if the issuer has a different base JID than the key to sign. This makes it possible to find the issuer key using PEP (see Public Key Publication via PEP).

+

While OpenPGP defines how to sign a string, X.509 does not specify the hash algorithm. For X.509 the signature data MUST contain an attribute what hash and sign algorithms were used. This document only defines 'RSA-SHA1' at this time. To make it easier to use standard cryptographic libraries the hash must contain the ASN.1 BER SHA1 algorithm designator prefix required in PKCS1. See XML-SIG section 6.4.2 how to hash and sign a string using RSA-SHA1. In most cases the cryptographic library will automatically take care of this. The data to sign is the X.509 certificate in DER encoding or the OpenPGP binary string of the fingerprint (the provided key data without Base64 encoding).

+

The next example contains am X.509 certificate signed by the key defined in the first example.

+ + 571b23d99892f4566017426e92c377288ed6c983 + + MIICXDCCAcWgAwIBAgIJAKBfLqul2lj3MA0GCSqGSIb3DQEBBQUAMCkxJzAlBgNV + BAMUHmRtZXllckBqYWJiZXIuY29tXDJmdGVzdGNsaWVudDAeFw0wODA5MDYxOTI0 + MjVaFw0wOTA5MDYxOTI0MjVaMCkxJzAlBgNVBAMUHmRtZXllckBqYWJiZXIuY29t + XDJmdGVzdGNsaWVudDCBnzANBgkqhkiG9w0BAQEFAAOBjQAwgYkCgYEAwaRLyj7J + /mmliYhjEwGnRGRs6gmcPaIywEK2QLFz6c3/RmRabYbIOE0iZ22D33TguSNQBWfd + lweT3bBETUhd3yuCcqWO5Ptiq/6wulMlxVeV5mxwNP/IF94VPWj0jHbRJcU8ZhS4 + UnX6R5q6OSfBGdUU4mYKdiaHpgqTAO9eeqUCAwEAAaOBizCBiDAdBgNVHQ4EFgQU + b8touIdFuXF5clv2I/S1aOOFdN4wWQYDVR0jBFIwUIAUb8touIdFuXF5clv2I/S1 + aOOFdN6hLaQrMCkxJzAlBgNVBAMUHmRtZXllckBqYWJiZXIuY29tXDJmdGVzdGNs + aWVudIIJAKBfLqul2lj3MAwGA1UdEwQFMAMBAf8wDQYJKoZIhvcNAQEFBQADgYEA + pA5tI1J9Qpn3jSoQctFksRLb2H3A48R3rU8/qnarwE/AyOvth3k3ulLEmhJBT+0S + mVb6WzrZEA/2plu7DhR8ylhuvJv6cAEIN+TPha3yzO2P8uoVZf7hdunOhMLl2Z6w + xEfiGI5X9OsaMeFOQa+B2C3uUVAMLbVV7Rp/qQkai1Y= + + + 428b1358a286430f628da23fb33ddaf6e474f5c5 + + E3q/UkjRR3zcZMcIIoE2sSVKUATl26zyzO1Pmoe96p8apW91c3a0KqkQp1ZMBqXX + +e2ImqQ79CKv+9qzXitxx+V4EcniKN0ZsSR+9ZbfflxkOvmBa2rpq9hFE1NYyfuT + fsAZkRhAGlP7P5ELcvhqJ4WL6qBPYQU2NEnbVlcZSbA= + + + + ]]> + + +

An entity SHOULD follow the best practices defined in &xep0222; to publish its long-term public keys via its own server. Processes for doing so are described in the following sections.

@@ -84,7 +178,7 @@
  • Items published to the node are persistent (this is done by setting the "persist_items" option to true).
  • Keys will be pushed to subscribers only when new keys are published, not when subscribers become newly available or when a new subscription is created (this is done by setting the "send_last_published_item" option to "never").
    • -
+

If the user wants to control access to his/her identity (see Security Considerations) then the node access model SHOULD be something other than "open" (this can be done by setting the "access_model" option to a value of "authorize", "presence", "roster", or "whitelist").

- - - julietRSAkey1hash - - - ... - AQAB - - - + + + julietPGPkey1hash + ... + @@ -156,67 +245,24 @@ ]]> -

The entity publishes a key by sending a pubsub publish request to the pubsub service. A previously published key can be updated by re-publishing the key using the same ItemID.

-

Each public key MUST be wrapped in a <KeyInfo/> element qualified by the 'http://www.w3.org/2000/09/xmldsig#' namespace as specified in &w3xmlsig;. Each <KeyInfo/> element MUST contain a <KeyName/> element with a name that is unique for the user; this enables the key to be referenced by other XMPP Extension Protocols (for example, &xep0136;). The name MAY be the same as the value of the ItemID. However, if two <KeyInfo/> elements contain the same public key in different formats (for example, an X.509 certificate may contain an RSA key), then the name of the two keys SHOULD be the same.

-

Before computing the fingerprint or publishing the key, all character data between all elements in the <KeyInfo/> element MUST be removed and the XML MUST be converted to canonical form according to &w3canon;. (Any whitespace or other character data shown in the examples herein is included only for the purpose of readability.)

-

The value of the ItemID SHOULD be set to the fingerprint of the public key, e.g., the SHA256 hash (see &nistfips180-2;) of the key's normalized <KeyValue/>, <PGPData/> or <X509Data/> element. Therefore subscribers or other interested entities are able to request a single key by specifying its fingerprint (for example, when a subscriber is using the &xep0116; protocol).

- - - - - - julietDSAkey1hash - - -

...

- ... - ... - ... - - - - - - - - ]]> +

The entity publishes a key by sending a pubsub publish request to the pubsub service. A previously published key can be updated by re-publishing the key using the same ItemID. The value of the ItemID SHOULD be set to the fingerprint of the public key (the name). Therefore subscribers or other interested entities are able to request a single key by specifying its fingerprint (for example, when a subscriber is using C2C Authentication Using TLS).

- - julietX509cert1hash - - - CN=TAMURA Kent, OU=TRL, O=IBM, L=Yamato-shi, ST=Kanagawa, C=JP - 12345678 - - 31d97bd7 - Subject of Certificate B - ... - ... - ... - - - - - - - ]]> - - - - - - julietPGPkey1hash - - ... - ... - - + + julietX509cert1hash + + ... + + + julietPGPkey1hash + + ... + + + @@ -227,16 +273,19 @@ - - - julietRSAkey1hash - - - ... - AQAB - - - + + + julietX509cert1hash + + ... + + + julietPGPkey1hash + + ... + + + @@ -267,29 +316,17 @@ id='items1'> - - - julietRSAkey1hash + + + julietPGPkey1hash ... - - - - - julietDSAkey1hash - ... - + - - julietX509cert1hash + + julietX509cert1hash ... - - - - - julietPGPkey1hash - ... - + @@ -302,7 +339,7 @@ id='items2'> - + @@ -314,16 +351,11 @@ id='items2'> - - - julietRSAkey1hash - - - ... - AQAB - - - + + + julietX509cert1hash + ... + @@ -348,18 +380,12 @@ to='romeo@montague.net/garden' from='juliet@capulet.com/balcony'> - + ... - - + + ... - - - ... - - - ... - + ]]> @@ -382,8 +408,8 @@ to='juliet@capulet.com/balcony' from='romeo@montague.net/garden'> - julietRSAkey1hash - julietRSAkey2hash + julietX509cert1hash + julietX509cert2hash ]]> @@ -393,12 +419,12 @@ to='romeo@montague.net/garden' from='juliet@capulet.com/balcony'> - + ... - - + + ... - + ]]> @@ -420,12 +446,12 @@ to='romeo@montague.net/garden' from='juliet@capulet.com/balcony'> - + ... - - + + ... - + ]]> @@ -448,22 +474,12 @@ - - - - ... - AQAB - - - - - - - ... - AQAB - - - + + ... + + + ... + ]]> @@ -496,18 +512,37 @@ - + - + + + + + + + + + + + + + + + + + + + + + + + ]]>