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commit 7703092b35dbd0084c26d277bb03cb7e21889add
Author: Werner Koch <wk at gnupg.org>
Date:   Fri May 6 09:51:55 2016 +0200

    drafts: Released first version of openpgp-webkey-service.

diff --git a/misc/id/openpgp-webkey-service/abstract.mkd b/misc/id/openpgp-webkey-service/abstract.mkd
new file mode 100644
index 0000000..d8596be
--- /dev/null
+++ b/misc/id/openpgp-webkey-service/abstract.mkd
@@ -0,0 +1,4 @@
+This specification describes a service to locate OpenPGP keys by mail
+address using a Web service and the HTTPS protocol.  It also provides
+a method for secure communication between the key owner and the mail
+provider to publish and revoke the public key.
diff --git a/misc/id/openpgp-webkey-service/back.mkd b/misc/id/openpgp-webkey-service/back.mkd
new file mode 100644
index 0000000..78d234b
--- /dev/null
+++ b/misc/id/openpgp-webkey-service/back.mkd
@@ -0,0 +1,23 @@
+# Test Vectors
+
+For help implementing this specification a non-normative example is
+given:
+
+## Sample key
+
+  TODO
+
+## Software Notes
+
+   GnuPG supports the key discovery described in this document since
+   version 2.1.12.  To use it, the new method "wkd" needs to be used
+   with the --auto-key-locate option.
+
+# Changes
+
+  - This is the initial draft.
+
+## TODO
+
+  - What about authenticated submission?
+  - Describe how to handle a key with several User IDs.
diff --git a/misc/id/openpgp-webkey-service/draft-koch-openpgp-webkey-service-00.txt b/misc/id/openpgp-webkey-service/draft-koch-openpgp-webkey-service-00.txt
new file mode 100644
index 0000000..4f271fc
--- /dev/null
+++ b/misc/id/openpgp-webkey-service/draft-koch-openpgp-webkey-service-00.txt
@@ -0,0 +1,560 @@
+
+
+
+
+Network Working Group                                            W. Koch
+Internet-Draft                                             GnuPG Project
+Intended status: Informational                               May 6, 2016
+Expires: November 7, 2016
+
+
+                        OpenPGP Web Key Service
+                  draft-koch-openpgp-webkey-service-00
+
+Abstract
+
+   This specification describes a service to locate OpenPGP keys by mail
+   address using a Web service and the HTTPS protocol.  It also provides
+   a method for secure communication between the key owner and the mail
+   provider to publish and revoke the public key.
+
+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).  Note that other groups may also distribute
+   working documents as Internet-Drafts.  The list of current Internet-
+   Drafts is at http://datatracker.ietf.org/drafts/current/.
+
+   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 November 7, 2016.
+
+Copyright Notice
+
+   Copyright (c) 2016 IETF Trust and the persons identified as the
+   document authors.  All rights reserved.
+
+   This document is subject to BCP 78 and the IETF Trust's Legal
+   Provisions Relating to IETF Documents
+   (http://trustee.ietf.org/license-info) in effect on the date of
+   publication of this document.  Please review these documents
+   carefully, as they describe your rights and restrictions with respect
+   to this document.  Code Components extracted from this document must
+   include Simplified BSD License text as described in Section 4.e of
+   the Trust Legal Provisions and are provided without warranty as
+   described in the Simplified BSD License.
+
+
+
+
+Koch                    Expires November 7, 2016                [Page 1]
+

+Internet-Draft           OpenPGP Web Key Service                May 2016
+
+
+Table of Contents
+
+   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   2
+   2.  Notational Conventions  . . . . . . . . . . . . . . . . . . .   2
+   3.  Web Key Directory . . . . . . . . . . . . . . . . . . . . . .   2
+     3.1.  Key Discovery . . . . . . . . . . . . . . . . . . . . . .   3
+   4.  Web Key Directory Update Protocol . . . . . . . . . . . . . .   4
+     4.1.  The Submission Address  . . . . . . . . . . . . . . . . .   5
+     4.2.  The Submission Mail . . . . . . . . . . . . . . . . . . .   6
+     4.3.  The Confirmation Request  . . . . . . . . . . . . . . . .   6
+     4.4.  The Confirmation Response . . . . . . . . . . . . . . . .   7
+     4.5.  Policy Flags  . . . . . . . . . . . . . . . . . . . . . .   8
+   5.  Security Considerations . . . . . . . . . . . . . . . . . . .   8
+   6.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .   9
+     6.1.  Well-Known URI  . . . . . . . . . . . . . . . . . . . . .   9
+   7.  Normative References  . . . . . . . . . . . . . . . . . . . .   9
+   Appendix A.  Test Vectors . . . . . . . . . . . . . . . . . . . .   9
+     A.1.  Sample key  . . . . . . . . . . . . . . . . . . . . . . .  10
+     A.2.  Software Notes  . . . . . . . . . . . . . . . . . . . . .  10
+   Appendix B.  Changes  . . . . . . . . . . . . . . . . . . . . . .  10
+     B.1.  TODO  . . . . . . . . . . . . . . . . . . . . . . . . . .  10
+   Author's Address  . . . . . . . . . . . . . . . . . . . . . . . .  10
+
+1.  Introduction
+
+   This memo describes a method to associate OpenPGP keys with a mail
+   address and now to look them up using a web service with a well-known
+   URI.  In addition a mail based protocol is given to allow a client to
+   setup such an association and to maintain it.
+
+2.  Notational Conventions
+
+   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].
+
+3.  Web Key Directory
+
+   A major use case for OpenPGP is the encryption of mail.  A common
+   difficulty of sending encrypted mails to a new communication partner
+   is to find the appropriate public key of the recipient.  Unless an
+   off-channel key exchange has been done, there are no easy ways to
+   discover the required key.  The common practice is to search the
+   network of public key servers for a key matching the recipient's mail
+   address.  This practise bears the problem that the keyservers are not
+   able to give a positive confirmation that a key actually belongs to
+   the mail addresses given in the key.  Further, there are often
+   several keys matching a mail address and thus one needs to pick a key
+
+
+
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+

+Internet-Draft           OpenPGP Web Key Service                May 2016
+
+
+   on good luck.  This is clearly not a secure way to setup an end-to-
+   end encryption.  Even if the need for a trusted key for an initial
+   mail message is relinquished, a non-authenticated key may be a wrong
+   one and the actual recipient would receive a mail which she can't
+   decrypt, due to the use of a wrong key.
+
+   Methods to overcome this problem are
+
+   o  sending an initial unencrypted messages with the public key
+      attached,
+
+   o  using the OpenPGP DANE protocol to lookup the recipients key via
+      the DNS.
+
+   The first method has the obvious problems of not even trying to
+   encrypt the initial mail, an extra mail round-trip, and problems with
+   unattended key discovery.
+
+   The latter method works fine but requires that mail providers need to
+   set up a separate DNS resolver to provide the key.  The
+   administration of a DNS zone is often not in the hands of small mail
+   installations.  Thus an update of the DNS resource records needs to
+   be delegated to the ISP running the DNS service.  Further, DNS
+   lookups are not encrypted and missing all confidentially.  Even if
+   the participating MUAs are using STARTTLS to encrypt the mail
+   exchange, a DNS lookup for the key unnecessary identifies the local-
+   part of the recipients mail address to any passive eavesdroppers.
+
+   This memo specified a new method for key discovery using an encrypted
+   https connection.
+
+3.1.  Key Discovery
+
+   Although URIs are able to encode all kind of characters,
+   straightforward implementations of a key directory may want to store
+   the "local-part" of a mail address directly in the file system.  This
+   forbids the use of certain characters in the "local-part".  To allow
+   for such an implementation method the URI uses an encoded form of the
+   "local-part" which can be directly mapped to a file name.
+
+   OpenPGP defines its User IDs, and thus the mail address, as UTF-8
+   strings.  To help with the common pattern of using capitalized names
+   (e.g.  "Joe.Doe at example.org") for mail addresses, and under the
+   premise that almost all MTAs treat the "local-part" case-insensitive
+   and that the "domain-part" is required to be compared case-
+   insensitive anyway, all upper-case ASCII characters in a User ID are
+   mapped to lowercase.  Non-ASCII characters are not changed.
+
+
+
+
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+Internet-Draft           OpenPGP Web Key Service                May 2016
+
+
+   The so mapped "local-part" is hashed using the SHA-1 algorithm.  The
+   resulting 160 bit digest is encoded using the Z-Base-32 method as
+   described in [RFC6189], section 5.1.6.  The resulting string has a
+   fixed length of 32 octets.  To form the URI, the scheme "https://" is
+   concatenated with the mapped "domain-part", the fixed string "./well-
+   known/openpgpkey/hu/", the "domain-part" again, and the above
+   constructed 32 octet string.
+
+   For example the URI to lookup the key for Joe.Doe at Example.ORG is:
+
+     https://example.org/.well-known/openpgpkey/
+     hu/example.org/iy9q119eutrkn8s1mk4r39qejnbu3n5q
+
+   (line has been wrapped for rendering purposes)
+
+   The HTTP GET method MUST return the binary representation of the
+   OpenPGP key for the given mail address.  The key needs to carry a
+   User ID packet ([RFC4880]) with that mail address.  Note that the key
+   may be revoked or expired - it is up to the client to handle such
+   conditions.  The server MUST also accept a HEAD method so that a
+   client may only check for the existence of a key.
+
+   The server SHOULD return "application/pgp-key" as the content-type
+   for the data but clients MUST also accept "application/octet-string"
+   as content-type.  The server MUST NOT return an ASCII armored version
+   of the key.
+
+4.  Web Key Directory Update Protocol
+
+   To put keys into the key directory a protocol to automate the task is
+   desirable.  The protocol defined here is entirely based on mail and
+   the assumption that a mail provider can securely deliver mail to the
+   INBOX of a user (e.g. an IMAP folder).  Note that the same protocol
+   may also be used for submitting keys for use with OpenPGP DANE.
+
+   We assume that the user already created a key for her mail account
+   alice at example.org.  To install the key at her provider's Web Key
+   Directory, she performs the following steps:
+
+   1.  She retrieves a file which contains one line with the mail
+       address used to submit the key to the mail provider.  See below
+       for the syntax of that file.  For a mail address at the domain
+       "example.org" the URI of the file is
+
+       https://example.org/.well-known/openpgpkey/submission-address
+
+   2.  She sends her key using SMTP (or any other transport mechanism)
+       to the provider using the submission address.  The content-type
+
+
+
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+
+
+       SHOULD be "application/pgp-key" and the key being a binary
+       attachment (which is then likely base64 encoded).  Note that the
+       OpenPGP ASCII armor is not used.
+
+   3.  The provider checks that the received key has a User ID which
+
+       *  matches an account name of the provider,
+
+       *  and that the from address matches that account.
+
+   4.  The provider sends an encrypted message containing a nonce and
+       the fingerprint of the key to the mail account of the user.  Note
+       that a similar scheme is used by the well known caff(1) tool to
+       help with key signing parties.
+
+   5.  A legitimate user will be able to decrypt the message because she
+       created the key and is in charge of the private key.  This step
+       verifies that the submitted key has actually been created by the
+       owner of the account.
+
+   6.  The user sends the decrypted nonce back to the submission address
+       as a confirmation that the private key is owned by her and that
+       the provider may now publish the key.  Also technically not
+       required, it is suggested that the mail to the provider is
+       encrypted.  The public key for this is retrieved using the key
+       lookup protocol described above.
+
+   7.  The provider receives the nonce, matches it with its database of
+       pending confirmations and then publishes the key.  Finally the
+       provider sends a mail back to the user to notify her of the the
+       publication of her key.
+
+   The message data structures used for the above protocol are specified
+   in detail below.  In the following sections the string "WELLKNOWN"
+   denotes the first part of an URI specific for a domain.  In the
+   examples the domain "example.org" is assumed, thus
+
+     WELLKNOWN := https://example.org/.well-known/openpgpkey
+
+   The term "target key" denotes the to be published key, the term
+   "submission key" the key associated with the submission-address of
+   the mail provider.
+
+4.1.  The Submission Address
+
+   The address of the submission file is
+
+     WELLKNOWN/submission-address
+
+
+
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+
+
+   The file consists of exactly one line, terminated by a LF, or the
+   sequence of CR and LF, with the full mail address to be used for
+   submission of a key to the mail provider.  For example the content of
+   the file may be
+
+     key-submission-example.org at directory.example.org
+
+4.2.  The Submission Mail
+
+   The mail used to submit a key to the mail provider MUST comply to the
+   PGP/MIME specification ([RFC3156], section 7), which states that the
+   Content-Type must be "application/pgp-keys", there are no required or
+   optional parameters, and the body part contains the ASCII-armored
+   transferable Public Key Packets as defined in [RFC4880], section
+   11.1.
+
+   If the mail provider has published an encryption key for the
+   submission-address in the Web Key Directory, the key to be published
+   MUST be submitted using a PGP/MIME encrypted message ([RFC3156],
+   section 4).  The message MUST not be signed (because the authenticity
+   of the signing key has not yet been confirmed).  After decryption of
+   the message at the mail provider a single "application/pgp-keys"
+   part, as specified above, is expected.
+
+4.3.  The Confirmation Request
+
+   The mail provider sends a confirmation mail in response to a received
+   key publication request.  The message SHOULD be sent from the
+   submission-address of the mail provider to the mail address extracted
+   from the target key.  The message needs to be encrypted to the target
+   key and MAY be signed by the submission key.  PGP/MIME MUST be used
+   for encryption and signing; the Combined method ([RFC3156], section
+   6.2) MUST be used if the message is to be signed.
+
+   The Content-type used for the plaintext part MUST be "application/
+   vnd.gnupg.wkd".  The body consists of name-value pairs with one name-
+   value pair per LF or CR+LF terminated line.  Empty lines are allowed
+   and will be ignored by the receiver.  A colon is used to terminate a
+   name.
+
+   In a confirmation request the following names MUST be send in the
+   specified order:
+
+   "type"  The value must be "confirmation-request".
+
+   "from"  This is the mailbox the user is expected to sent the
+      confirmation response to.  The value must match the mailbox part
+      of the "From:" address of this request.
+
+
+
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+

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+
+
+   "address"  The value is the addr-spec part of the target key's mail
+      address.  The value SHOULD match the addr-spec part of the
+      recipient's address.  The value MUST be be UTF-8 encoded as
+      required for an OpenPGP User ID.
+
+   "fingerprint"  The value is the fingerprint of the target key.  The
+      fingerprint is given in uppercase hex encoding without any
+      interleaving spaces.
+
+   "nonce"  The value is a string with a minimum length of 16 octets and
+      a maximum length of 64 octets.  The string must entirely be made
+      up of random ASCII letters or digits.  This nonce will be sent
+      back to the mail provider as proof that the recipient is the
+      legitimate owner of the target-key.
+
+   The receiver of the message decrypts the message, checks that the
+   "fingerprint" matches the target key, checks that the "address"
+   matches a User ID of the target key, and checks the other constrains
+   of the request format.  If any constraint is not asserted, or the
+   fingerprint or User ID do not match the target key, or there is no
+   pending publication requests (i.e. a mail recently sent o the
+   submission address), the user MAY be notified about this fake
+   confirmation attempt.
+
+   In other cases the confirmation request is legitimate and the MUA
+   shall silently send a response as described in the next section.
+
+4.4.  The Confirmation Response
+
+   A response to a confirmation request MUST only be send in the
+   positive case; there is no negative confirmation response.  A mail
+   service provider is expected to cancel a pending key submission after
+   a suitable time without a confirmation.  The mail service provider
+   SHOULD not retry the sending of a confirmation request after the
+   first request has been send successfully.
+
+   The user MUST send the confirmation response from her target mail
+   address to the "from" address of the confirmation request.  The
+   message MUST be signed and SHOULD be encrypted.  The PGP/MIME
+   Combined format MUST be used for encryption and signing ([RFC3156],
+   section 6.2).  The encryption key can be taken from the Web Key
+   Directory.
+
+   The Content-type used for the plaintext message MUST also be
+   "application/vnd.gnupg.wkd".  The format is the same as described
+   above for the Confirmation Request.  The body must contain three
+   name-value pairs in this order:
+
+
+
+
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+

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+
+
+   "type"  The value must be "confirmation-response".
+
+   "from"  The value must match the mailbox part of the "From:" address
+      of this response.
+
+   "nonce"  The value is the value of the "nonce" parameter from the
+      confirmation request.
+
+4.5.  Policy Flags
+
+   For key generation and submission it is sometimes useful to tell the
+   client about certain properties of the mail provider in advance.
+   This can be done with a file at the URL
+
+     WELLKNOWN/policy
+
+   The file contains keywords, one per line with each line terminated by
+   a LF or the sequence of CR and LF.  Empty lines and lines starting
+   with a '#' character are considered comment lines.  A keyword is made
+   up of lowercase letters, digits, hyphens, or dots.  An underscore is
+   allowed as a name space delimiters; see below.  The first character
+   must be a letter.  Clients MUST use case-insensitive matching.
+
+   Currently defined keywords are:
+
+   "mailbox-only"  The mail server provider does only accept keys with
+      only a mailbox in the User ID.  In particular User IDs with a real
+      name in addition to the mailbox will be rejected as invalid.
+
+   More keywords will be defined in updates to this I-D.  There is no
+   registry yet except for this document.  For experimental use of new
+   features or for provider specific settings, keywords MUST be prefixed
+   with a domain name and an underscore.
+
+5.  Security Considerations
+
+   The use of SHA-1 for the mapping of the "local-part" to a fixed
+   string is not a security feature but merely used to map the local-
+   part to a fixed-sized string made from a well defined set of
+   characters.  It is not intended to conceal information about a mail
+   address.
+
+   The domain name part of the mail address is not part of the hash to
+   avoid problems with internationalized domain names.  Instead a
+   separate web service is required for each domain name.
+
+
+
+
+
+
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+

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+
+
+6.  IANA Considerations
+
+6.1.  Well-Known URI
+
+   IANA is requested to assign a well-known URI in the "Well-Known URIs"
+   registry as defined by [RFC5785]:
+
+   URI suffix: openpgpkey
+
+   Change controller: IETF
+
+   Specification document: This
+
+7.  Normative References
+
+   [RFC0822]  Crocker, D., "STANDARD FOR THE FORMAT OF ARPA INTERNET
+              TEXT MESSAGES", STD 11, RFC 822, DOI 10.17487/RFC0822,
+              August 1982, <http://www.rfc-editor.org/info/rfc822>.
+
+   [RFC2119]  Bradner, S., "Key words for use in RFCs to Indicate
+              Requirement Levels", BCP 14, RFC 2119, March 1997.
+
+   [RFC3156]  Elkins, M., Del Torto, D., Levien, R., and T. Roessler,
+              "MIME Security with OpenPGP", RFC 3156, August 2001.
+
+   [RFC4880]  Callas, J., Donnerhacke, L., Finney, H., Shaw, D., and R.
+              Thayer, "OpenPGP Message Format", RFC 4880, November 2007.
+
+   [RFC5226]  Narten, T. and H. Alvestrand, "Guidelines for Writing an
+              IANA Considerations Section in RFCs", BCP 26, RFC 5226,
+              May 2008.
+
+   [RFC5785]  Nottingham, M. and E. Hammer-Lahav, "Defining Well-Known
+              Uniform Resource Identifiers (URIs)", RFC 5785, DOI
+              10.17487/RFC5785, April 2010,
+              <http://www.rfc-editor.org/info/rfc5785>.
+
+   [RFC6189]  Zimmermann, P., Johnston, A., Ed., and J. Callas, "ZRTP:
+              Media Path Key Agreement for Unicast Secure RTP", RFC
+              6189, DOI 10.17487/RFC6189, April 2011,
+              <http://www.rfc-editor.org/info/rfc6189>.
+
+Appendix A.  Test Vectors
+
+   For help implementing this specification a non-normative example is
+   given:
+
+
+
+
+
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+
+
+A.1.  Sample key
+
+   TODO
+
+A.2.  Software Notes
+
+   GnuPG supports the key discovery described in this document since
+   version 2.1.12.  To use it, the new method "wkd" needs to be used
+   with the --auto-key-locate option.
+
+Appendix B.  Changes
+
+   o  This is the initial draft.
+
+B.1.  TODO
+
+   o  What about authenticated submission?
+
+   o  Describe how to handle a key with several User IDs.
+
+Author's Address
+
+   Werner Koch
+   GnuPG Project
+
+   Email: wk at gnupg.org
+   URI:   https://gnupg.org
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+Koch                    Expires November 7, 2016               [Page 10]
diff --git a/misc/id/openpgp-webkey-service/middle.mkd b/misc/id/openpgp-webkey-service/middle.mkd
new file mode 100644
index 0000000..3f0e63f
--- /dev/null
+++ b/misc/id/openpgp-webkey-service/middle.mkd
@@ -0,0 +1,336 @@
+# Introduction
+
+This memo describes a method to associate OpenPGP keys with a mail
+address and now to look them up using a web service with a well-known
+URI.  In addition a mail based protocol is given to allow a client to
+setup such an association and to maintain it.
+
+# Notational Conventions
+
+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).
+
+
+# Web Key Directory
+
+A major use case for OpenPGP is the encryption of mail.  A common
+difficulty of sending encrypted mails to a new communication partner is
+to find the appropriate public key of the recipient.  Unless an
+off-channel key exchange has been done, there are no easy ways to
+discover the required key.  The common practice is to search the
+network of public key servers for a key matching the recipient's mail
+address.  This practise bears the problem that the keyservers are not
+able to give a positive confirmation that a key actually belongs to
+the mail addresses given in the key.  Further, there are often several
+keys matching a mail address and thus one needs to pick a key on good
+luck.  This is clearly not a secure way to setup an end-to-end
+encryption.  Even if the need for a trusted key for an initial mail
+message is relinquished, a non-authenticated key may be a wrong one
+and the actual recipient would receive a mail which she can't decrypt,
+due to the use of a wrong key.
+
+Methods to overcome this problem are
+
+ - sending an initial unencrypted messages with the public key
+   attached,
+ - using the OpenPGP DANE protocol to lookup the recipients key via
+   the DNS.
+
+The first method has the obvious problems of not even trying to
+encrypt the initial mail, an extra mail round-trip, and problems with
+unattended key discovery.
+
+The latter method works fine but requires that mail providers need to
+set up a separate DNS resolver to provide the key.  The administration
+of a DNS zone is often not in the hands of small mail installations.
+Thus an update of the DNS resource records needs to be delegated
+to the ISP running the DNS service.  Further, DNS lookups are not
+encrypted and missing all confidentially.  Even if the participating
+MUAs are using STARTTLS to encrypt the mail exchange, a DNS lookup for
+the key unnecessary identifies the local-part of the recipients mail
+address to any passive eavesdroppers.
+
+This memo specified a new method for key discovery using an encrypted
+https connection.
+
+## Key Discovery
+
+Although URIs are able to encode all kind of characters,
+straightforward implementations of a key directory may want to store
+the "local-part" of a mail address directly in the file system.  This
+forbids the use of certain characters in the "local-part".  To allow
+for such an implementation method the URI uses an encoded form of the
+"local-part" which can be directly mapped to a file name.
+
+OpenPGP defines its User IDs, and thus the mail address, as UTF-8
+strings.  To help with the common pattern of using capitalized names
+(e.g. "Joe.Doe at example.org") for mail addresses, and under the premise
+that almost all MTAs treat the "local-part" case-insensitive and that
+the "domain-part" is required to be compared case-insensitive anyway,
+all upper-case ASCII characters in a User ID are mapped to lowercase.
+Non-ASCII characters are not changed.
+
+The so mapped "local-part" is hashed using the SHA-1 algorithm.  The
+resulting 160 bit digest is encoded using the Z-Base-32 method as
+described in [](#RFC6189), section 5.1.6.  The resulting string has a
+fixed length of 32 octets.  To form the URI, the scheme "https://" is
+concatenated with the mapped "domain-part", the fixed string
+"./well-known/openpgpkey/hu/", the "domain-part" again, and the above
+constructed 32 octet string.
+
+For example the URI to lookup the key for Joe.Doe at Example.ORG is:
+
+      https://example.org/.well-known/openpgpkey/
+      hu/example.org/iy9q119eutrkn8s1mk4r39qejnbu3n5q
+
+(line has been wrapped for rendering purposes)
+
+The HTTP GET method MUST return the binary representation of the
+OpenPGP key for the given mail address.  The key needs to carry a User
+ID packet ([](#RFC4880)) with that mail address.  Note that the key
+may be revoked or expired - it is up to the client to handle such
+conditions.  The server MUST also accept a HEAD method so that a
+client may only check for the existence of a key.
+
+The server SHOULD return "application/pgp-key" as the content-type for
+the data but clients MUST also accept "application/octet-string" as
+content-type.  The server MUST NOT return an ASCII armored version of
+the key.
+
+
+# Web Key Directory Update Protocol
+
+To put keys into the key directory a protocol to automate the task is
+desirable.  The protocol defined here is entirely based on mail and
+the assumption that a mail provider can securely deliver mail to the
+INBOX of a user (e.g. an IMAP folder).  Note that the same protocol
+may also be used for submitting keys for use with OpenPGP DANE.
+
+We assume that the user already created a key for her mail account
+alice at example.org.  To install the key at her provider's Web Key
+Directory, she performs the following steps:
+
+1. She retrieves a file which contains one line with the mail address
+   used to submit the key to the mail provider.  See below for the
+   syntax of that file.  For a mail address at the domain "example.org"
+   the URI of the file is
+
+      https://example.org/.well-known/openpgpkey/submission-address
+
+2. She sends her key using SMTP (or any other transport mechanism) to
+   the provider using the submission address.  The content-type SHOULD
+   be "application/pgp-key" and the key being a binary attachment
+   (which is then likely base64 encoded).  Note that the OpenPGP ASCII
+   armor is not used.
+
+3. The provider checks that the received key has a User ID which
+    - matches an account name of the provider,
+    - and that the from address matches that account.
+
+4. The provider sends an encrypted message containing a nonce and the
+   fingerprint of the key to the mail account of the user.  Note that
+   a similar scheme is used by the well known caff(1) tool to
+   help with key signing parties.
+
+5. A legitimate user will be able to decrypt the message because she
+   created the key and is in charge of the private key.  This step
+   verifies that the submitted key has actually been created by the
+   owner of the account.
+
+6. The user sends the decrypted nonce back to the submission address
+   as a confirmation that the private key is owned by her and that the
+   provider may now publish the key.  Also technically not required,
+   it is suggested that the mail to the provider is encrypted.  The
+   public key for this is retrieved using the key lookup protocol
+   described above.
+
+7. The provider receives the nonce, matches it with its database of
+   pending confirmations and then publishes the key.  Finally the
+   provider sends a mail back to the user to notify her of the
+   the publication of her key.
+
+The message data structures used for the above protocol are specified
+in detail below.  In the following sections the string "WELLKNOWN"
+denotes the first part of an URI specific for a domain.  In the
+examples the domain "example.org" is assumed, thus
+
+      WELLKNOWN := https://example.org/.well-known/openpgpkey
+
+The term "target key" denotes the to be published key, the term
+"submission key" the key associated with the submission-address of the
+mail provider.
+
+## The Submission Address
+
+The address of the submission file is
+
+      WELLKNOWN/submission-address
+
+The file consists of exactly one line, terminated by a LF, or the
+sequence of CR and LF, with the full mail address to be used for
+submission of a key to the mail provider.  For example the content of
+the file may be
+
+      key-submission-example.org at directory.example.org
+
+## The Submission Mail
+
+The mail used to submit a key to the mail provider MUST comply to the
+PGP/MIME specification ([](#RFC3156), section 7), which states that the
+Content-Type must be "application/pgp-keys", there are no required or
+optional parameters, and the body part contains the ASCII-armored
+transferable Public Key Packets as defined in [](#RFC4880),
+section 11.1.
+
+If the mail provider has published an encryption key for the
+submission-address in the Web Key Directory, the key to be published
+MUST be submitted using a PGP/MIME encrypted message ([](#RFC3156),
+section 4).  The message MUST not be signed (because the
+authenticity of the signing key has not yet been confirmed).  After
+decryption of the message at the mail provider a single
+"application/pgp-keys" part, as specified above, is expected.
+
+## The Confirmation Request
+
+The mail provider sends a confirmation mail in response to a received
+key publication request.  The message SHOULD be sent from the
+submission-address of the mail provider to the mail address extracted
+from the target key.  The message needs to be encrypted to the target
+key and MAY be signed by the submission key.  PGP/MIME MUST be used
+for encryption and signing; the Combined method ([](#RFC3156),
+section 6.2) MUST be used if the message is to be signed.
+
+The Content-type used for the plaintext part MUST be
+"application/vnd.gnupg.wkd".  The body consists of name-value pairs
+with one name-value pair per LF or CR+LF terminated line.  Empty lines
+are allowed and will be ignored by the receiver.  A colon is used to
+terminate a name.
+
+In a confirmation request the following names MUST be send in the
+specified order:
+
+"type"
+  : The value must be "confirmation-request".
+
+"from"
+  : This is the mailbox the user is expected to sent the confirmation
+    response to.  The value must match the mailbox part of the
+    "From:" address of this request.
+
+"address"
+  : The value is the addr-spec part of the target key's mail address.
+    The value SHOULD match the addr-spec part of the recipient's
+    address.  The value MUST be be UTF-8 encoded as required for an
+    OpenPGP User ID.
+
+"fingerprint"
+  : The value is the fingerprint of the target key.  The fingerprint
+    is given in uppercase hex encoding without any interleaving
+    spaces.
+
+"nonce"
+  : The value is a string with a minimum length of 16 octets and a
+    maximum length of 64 octets.  The string must entirely be made up
+    of random ASCII letters or digits.  This nonce will be sent back
+    to the mail provider as proof that the recipient is the legitimate
+    owner of the target-key.
+
+
+The receiver of the message decrypts the message, checks that the
+"fingerprint" matches the target key, checks that the "address"
+matches a User ID of the target key, and checks the other constrains
+of the request format.  If any constraint is not asserted, or the
+fingerprint or User ID do not match the target key, or there is no
+pending publication requests (i.e. a mail recently sent o the
+submission address), the user MAY be notified about this fake
+confirmation attempt.
+
+In other cases the confirmation request is legitimate and the MUA
+shall silently send a response as described in the next section.
+
+## The Confirmation Response
+
+A response to a confirmation request MUST only be send in the positive
+case; there is no negative confirmation response.  A mail service
+provider is expected to cancel a pending key submission after a
+suitable time without a confirmation.  The mail service provider
+SHOULD not retry the sending of a confirmation request after the first
+request has been send successfully.
+
+The user MUST send the confirmation response from her target mail
+address to the "from" address of the confirmation request.  The
+message MUST be signed and SHOULD be encrypted.  The PGP/MIME Combined
+format MUST be used for encryption and signing ([](#RFC3156),
+section 6.2).  The encryption key can be taken from the Web Key
+Directory.
+
+The Content-type used for the plaintext message MUST also be
+"application/vnd.gnupg.wkd".  The format is the same as described
+above for the Confirmation Request.  The body must contain three
+name-value pairs in this order:
+
+"type"
+  : The value must be "confirmation-response".
+
+"from"
+  : The value must match the mailbox part of the "From:" address of
+    this response.
+
+"nonce"
+  : The value is the value of the "nonce" parameter from the
+    confirmation request.
+
+
+## Policy Flags
+
+For key generation and submission it is sometimes useful to tell the
+client about certain properties of the mail provider in advance.  This
+can be done with a file at the URL
+
+      WELLKNOWN/policy
+
+The file contains keywords, one per line with each line terminated by
+a LF or the sequence of CR and LF.  Empty lines and lines starting
+with a '#' character are considered comment lines.  A keyword is made
+up of lowercase letters, digits, hyphens, or dots.  An underscore is
+allowed as a name space delimiters; see below.  The first character
+must be a letter.  Clients MUST use case-insensitive matching.
+
+Currently defined keywords are:
+
+"mailbox-only"
+  : The mail server provider does only accept keys with only a mailbox
+    in the User ID.  In particular User IDs with a real name in
+    addition to the mailbox will be rejected as invalid.
+
+More keywords will be defined in updates to this I-D.  There is no
+registry yet except for this document.  For experimental use of new
+features or for provider specific settings, keywords MUST be prefixed
+with a domain name and an underscore.
+
+
+# Security Considerations
+
+The use of SHA-1 for the mapping of the "local-part" to a fixed string
+is not a security feature but merely used to map the local-part to a
+fixed-sized string made from a well defined set of characters.  It is
+not intended to conceal information about a mail address.
+
+The domain name part of the mail address is not part of the hash to
+avoid problems with internationalized domain names.  Instead a
+separate web service is required for each domain name.
+
+
+# IANA Considerations
+
+## Well-Known URI
+
+IANA is requested to assign a well-known URI in the "Well-Known URIs"
+registry as defined by [](#RFC5785):
+
+  URI suffix: openpgpkey
+
+  Change controller: IETF
+
+  Specification document: This
diff --git a/misc/id/openpgp-webkey-service/template.xml b/misc/id/openpgp-webkey-service/template.xml
new file mode 100644
index 0000000..c14ef88
--- /dev/null
+++ b/misc/id/openpgp-webkey-service/template.xml
@@ -0,0 +1,61 @@
+<?xml version="1.0" ?>
+<!DOCTYPE rfc SYSTEM 'rfc2629.dtd' [
+  <!ENTITY pandocAbstract PUBLIC '' 'abstract.xml'>
+  <!ENTITY pandocMiddle   PUBLIC '' 'middle.xml'>
+  <!ENTITY pandocBack     PUBLIC '' 'back.xml'>
+  <!ENTITY rfc.0822       PUBLIC '' '../common/reference.RFC.0822.xml'>
+  <!ENTITY rfc.2119       PUBLIC '' '../common/reference.RFC.2119.xml'>
+  <!ENTITY rfc.3156       PUBLIC '' '../common/reference.RFC.3156.xml'>
+  <!ENTITY rfc.4880       PUBLIC '' '../common/reference.RFC.4880.xml'>
+  <!ENTITY rfc.5226       PUBLIC '' '../common/reference.RFC.5226.xml'>
+  <!ENTITY rfc.5785       PUBLIC '' '../common/reference.RFC.5785.xml'>
+  <!ENTITY rfc.6189       PUBLIC '' '../common/reference.RFC.6189.xml'>
+]>
+
+<rfc ipr="trust200902" category="info"
+     docName="draft-koch-openpgp-webkey-service-00">
+
+<?rfc toc="yes"?>
+<?rfc symrefs="yes"?>
+<?rfc sortrefs="yes"?>
+<?rfc subcompact="no"?>
+<?rfc compact="yes"?>
+<?rfc comments="yes"?>
+
+
+  <front>
+    <title>OpenPGP Web Key Service</title>
+    <author initials="W." surname="Koch"
+            fullname="Werner Koch">
+      <organization>GnuPG Project</organization>
+      <address>
+        <email>wk at gnupg.org</email>
+        <uri>https://gnupg.org</uri>
+      </address>
+    </author>
+
+    <date month="May" year="2016" />
+    <area>Security</area>
+
+    <abstract>
+      &pandocAbstract;
+    </abstract>
+  </front>
+
+  <middle>
+    &pandocMiddle;
+  </middle>
+
+  <back>
+    <references title="Normative References">
+      &rfc.2119;
+      &rfc.3156;
+      &rfc.4880;
+      &rfc.5226;
+      &rfc.5785;
+      &rfc.0822;
+      &rfc.6189;
+    </references>
+    &pandocBack;
+  </back>
+</rfc>

-----------------------------------------------------------------------

Summary of changes:
 misc/id/openpgp-webkey-service/abstract.mkd        |   4 +
 misc/id/openpgp-webkey-service/back.mkd            |  23 +
 .../draft-koch-openpgp-webkey-service-00.txt       | 560 +++++++++++++++++++++
 misc/id/openpgp-webkey-service/middle.mkd          | 336 +++++++++++++
 .../template.xml                                   |  35 +-
 5 files changed, 938 insertions(+), 20 deletions(-)
 create mode 100644 misc/id/openpgp-webkey-service/abstract.mkd
 create mode 100644 misc/id/openpgp-webkey-service/back.mkd
 create mode 100644 misc/id/openpgp-webkey-service/draft-koch-openpgp-webkey-service-00.txt
 create mode 100644 misc/id/openpgp-webkey-service/middle.mkd
 copy misc/id/{eddsa-for-openpgp => openpgp-webkey-service}/template.xml (57%)


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