IPP Mail Archive: IPP> RE: HTTP/TLS draft

IPP Mail Archive: IPP> RE: HTTP/TLS draft

IPP> RE: HTTP/TLS draft

Rodney Thayer (Rodney@unitran.com)
Sat, 22 Aug 1998 17:36:29 -0400

I've put this on the agenda for the TLS meeting. I myself wasn't aware
of this draft (did they announce it on the TLS list?) and I see it
doesn't reference Eric's draft, which I know Keith was aware of, so I'm
feeling confused...

-----Original Message-----
From: Manros, Carl-Uno B [mailto:cmanros@cp10.es.xerox.com]
Sent: Saturday, August 22, 1998 12:13 PM
To: IETF Transport Layer Security WG
Cc: ipp@pwg.org
Subject: RE: HTTP/TLS draft

I have a follow-up question on the previous post.

Is the intent of the "HTTP Over TLS" draft to have it published as a
standards track document or only as an informational document?

The expectation from the IPP group was that it would go on the standards
track so that we could reference it, otherwise we cannot. The HTTP and
WebDAV groups would be in same boat I expect.

What is the general rule for TLS profile documents? Are they expected to
be standards track level documents or what?
Maybe this is stated somewhere in the TLS documents, but if so I missed
it.

Carl-Uno

> -----Original Message-----
> From: Manros, Carl-Uno B [mailto:cmanros@cp10.es.xerox.com]
> Sent: Saturday, August 22, 1998 5:12 AM
> To: IETF Transport Layer Security WG
> Cc: ipp@pwg.org
> Subject: RE: HTTP/TLS draft
>
>
> Eric,
>
> Thanks for getting this out, even if it did not make the Chicago
> deadline.
>
> As you know, we have been intending to apply this profile for the IPP
> protocol.
>
> However, we still seem to have a certain disconnect here. The two
> Application Area Directors recently brought to paper a number of rules
> for how to use security in applications run over HTTP 1.1.
>
> Here is the title and a quote from that document:
>
> ---
>
> On the use of HTTP as a Substrate for Other Protocols
> <draft-iesg-using-http-00.txt>
> 5 August 1998
>
> Note that the convention of appending an "s" to the URL scheme to
> mean "use TLS or SSL" (as in "http:" vs "https:") is
> nonstandard and
> should not be propagated. For most applications, a single
> "use TLS or
> SSL" bit is not sufficient to adequately convey the
> information that a
> client needs to authenticate itself to a server, even if
> it has the
> proper credentials. Authentication or other
> connection setup
> information should be communicated in URL parameters, rather
> than in the
> URL prefix.
>
> -----
>
> I know that they have also stated elsewhere that they do not
> want to see
> a special port # such as 443 useed for security.
>
> Is there any chance that we can overcome these differences?
>
> Carl-Uno
>
> > -----Original Message-----
> > From: EKR [mailto:ekr@terisa.com]
> > Sent: Wednesday, August 19, 1998 8:53 AM
> > To: IETF Transport Layer Security WG
> > Subject: HTTP/TLS draft
> >
> >
> > First off, I want to apologize for my failure to make the draft
> > deadline. I've been real busy, but I still should have made it.
> >
> > That said, here's a slightly touched up version of the HTTP/TLS
> > draft. I think it should fix the wildcard issue (no longer
> references
> > PKIX for wildcarding) and align more closely with Keith Moore's
> > suggestions for handling name matching.
> >
> > Comments welcome,
> >
> > - -Ekr
> >
> > - ----
> >
> >
> E. Rescorla
> > INTERNET-DRAFT Terisa
> Systems, Inc.
> > <draft-ietf-tls-https-02.txt> September 1998
> (Expires March-99)
> >
> > HTTP Over TLS
> >
> > Status of this Memo
> >
> > This document is an Internet-Draft. Internet-Drafts are working
> > documents of the Internet Engineering Task Force (IETF),
> its areas,
> > and its working groups. Note that other groups may also
> distribute
> > working documents as Internet-Drafts.
> >
> > 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.''
> >
> > To learn the current status of any Internet-Draft,
> please check the
> > ``1id-abstracts.txt'' listing contained in the
> > Internet-Drafts Shadow
> > Directories on ftp.is.co.za (Africa), nic.nordu.net (Europe),
> > munnari.oz.au (Pacific Rim), ds.internic.net (US East Coast), or
> > ftp.isi.edu (US West Coast).
> > Abstract
> >
> > This memo describes how to use TLS to secure HTTP
> connections over
> > the Internet. Current practice is to layer HTTP over SSL
> > (the prede-
> > cessor to TLS), distinguishing secured traffic from
> > insecure traffic
> > by the use of a different server port. This document
> documents that
> > practice using TLS. A companion document describes a
> > method for using
> > HTTP/TLS over the same port as normal HTTP.
> >
> > 1. Introduction
> >
> > HTTP [RFC2068] was originally used in the clear on the Internet.
> > However, increased use of HTTP for sensitive applications has
> > required security measures. SSL, and its successor TLS [TLS] were
> > designed to provide channel-oriented security. This document
> > describes how to use HTTP over TLS.
> >
> > 1.1. Discussion of this Draft
> >
> > This draft is being discussed on the "ietf-apps-tls"
> > mailing list. To
> > subscribe, send a message to:
> >
> > ietf-apps-tls-request@imc.org
> >
> > with the single word
> >
> >
> >
> > Rescorla
> > [Page 1]
> > Internet-Draft HTTP Over TLS
> >
> >
> >
> > subscribe
> >
> > in the body of the message. There is a Web site for the
> > mailing list
> > at <http://www.imc.org/ietf-apps-tls/>.
> >
> > 1.2. Requirements Terminology
> >
> > Keywords "MUST", "MUST NOT", "REQUIRED", "SHOULD",
> "SHOULD NOT" and
> > "MAY" that appear in this document are to be interpreted
> > as described
> > in [RFC2119].
> >
> > 2. HTTP Over TLS
> >
> > Conceptually, HTTP/TLS is very simple. Simply use HTTP
> > over TLS pre-
> > cisely as you would use HTTP over TCP.
> >
> > 2.1. Connection Initiation
> >
> > The agent acting as the HTTP client should also act as the TLS
> > client. It should initiate a connection to the server on the
> > appropriate port and then send the TLS ClientHello to
> begin the TLS
> > handshake. When the TLS handshake has finished. The
> client may then
> > initiate the first HTTP request. All HTTP data MUST be
> sentas TLS
> > "application data". Normal HTTP behavior, including
> > retained connec-
> > tions should be followed.
> >
> > 2.2. Connection Closure
> >
> > TLS provides a facility for secure connection closure.
> When a valid
> > closure alert is received, an implementation can be
> assured that no
> > further data will be received on that connection. TLS
> implementa-
> > tions MUST initiate an exchange of closure alerts before
> closing a
> > connection. A TLS implementation MAY, after sending a
> > closure alert,
> > close the connection without waiting for the peer to send
> > its closure
> > alert, generating an "incomplete close". Note that an
> > implementation
> > which does this MAY choose to reuse the session. This
> > SHOULD only be
> > done when the application knows (typically through detecting HTTP
> > message boundaries) that it has received all the message
> > data that it
> > cares about.
> >
> > As specified in [TLS], any implementation which receives a
> > connection
> > close without first receiving a valid closure alert (a "premature
> > close") MUST NOT reuse that session. Note that a premature
> > close does
> > not call into question the security of the data already
> > received, but
> > simply indicates that subsequent data might have been truncated.
> > Because TLS is oblivious to HTTP request/response
> boundaries, it is
> > necessary to examine the HTTP data itself (specifically
> > the Content-
> >
> >
> >
> > Rescorla
> > [Page 2]
> > Internet-Draft HTTP Over TLS
> >
> >
> > Length header) to determine whether the truncation
> > occurred inside a
> > message or between messages.
> >
> > 2.2.1. Client Behavior
> >
> > Because HTTP uses connection closure to signal end of
> server data,
> > client implementations MUST treat any premature closes as
> > errors and
> > the data received as potentially truncated. Two cases in
> particular
> > deserve special note:
> >
> > A HTTP response without a Content-Length header.
> > Since data length in
> > this situation is signalled by connection close a
> > premature close
> > generated by the server cannot be distinguished
> > from a spurious
> > close generated by an attacker.
> >
> > A HTTP response with a valid Content-Length header
> > closed before
> > all data has been read. Because TLS does not
> > provide document oriented protection, it is
> > impossible to determine whether the server has
> > miscomputed the
> > Content-Length or an attacker has truncated the
> connection.
> >
> >
> > When encountering a premature close, a client SHOULD
> treat as com-
> > pleted all requests for which it has received as much data
> > as speci-
> > fied in the Content-Length header.
> >
> > A client detecting an incomplete close SHOULD recover
> > gracefully. It
> > MAY resume a TLS session closed in this fashion.
> >
> > Clients MUST send a closure alert before closing the connection.
> > Clients which are unprepared to receive any more data MAY
> > choose not
> > to wait for the server's closure alert and simply close
> the connec-
> > tion, thus generating an incomplete close on the server side.
> >
> > 2.2.2. Server Behavior
> >
> > RFC2068 permits an HTTP client to close the connection
> at any time,
> > and requires servers to recover gracefully. In
> particular, servers
> > SHOULD be prepared to receive an incomplete close from
> the client,
> > since the client can often determine when the end of
> > server data is.
> > Servers SHOULD be willing to resume TLS sessions closed in this
> > fashion.
> >
> > Implementation note: In HTTP implementations which do
> not use per-
> > sistent connections, the server ordinarily expects to be
> > able to sig-
> > nal end of data by closing the connection. When Content-Length is
> > used, however, the client may have already sent the
> > closure alert and
> > dropped the connection.
> >
> >
> >
> >
> > Rescorla
> > [Page 3]
> > Internet-Draft HTTP Over TLS
> >
> >
> > Servers MUST attempt to initiate an exchange of closure
> alerts with
> > the client before closing the connection. Servers MAY
> > close the con-
> > nection after sending the closure alert, thus generating
> an incom-
> > plete close on the client side.
> >
> > 2.3. Port Number
> >
> > The first data that an HTTP server expects to receive from
> > the client
> > is the Request-Line production. The first data that a TLS
> > server (and
> > hence an HTTP/TLS server) expects to receive is the
> > ClientHello. Con-
> > sequently, common practice has been to run HTTP/TLS over
> a separate
> > port in order to distinguish which protocol is being used. When
> > HTTP/TLS is being run over a TCP/IP connection, the
> default port is
> > 443. This does not preclude HTTP/TLS from being run over another
> > transport. TLS only presumes a reliable connection-oriented data
> > stream.
> >
> > 2.4. URI Format
> >
> > HTTP/TLS is differentiated from HTTP URIs by using the
> > 'https' proto-
> > col identifier in place of the 'http' protocol identifier.
> > An example
> > URI specifying HTTP/TLS is:
> >
> > https://abc.com:80/~smith/home.html
> >
> >
> > 3. Endpoint Identification
> >
> > 3.1. Server Identity
> >
> > In general, HTTP/TLS requests are generated by
> dereferencing a URI.
> > As a consequence, the hostname for the server is known to
> > the client.
> > If the hostname is available, the client MUST check it
> against the
> > server's identity as presented in the server's
> Certificate message,
> > in order to prevent man-in-the-middle attacks.
> >
> > If the client has external information as to the expected
> > identity of
> > the server, the hostname check MAY be omitted. (For instance, a
> > client may be connecting to a machine whose address and
> > hostname are
> > dynamic but the client knows the certificate that the server will
> > present.) In such cases, it is important to narrow the scope of
> > acceptable certificates as much as possible in order to
> prevent man
> > in the middle attacks. In special cases, it may be
> appropriate for
> > the client to simply ignore the server's identity, but it must be
> > understood that this leaves the connection open to active attack.
> >
> > If a subjectAltName extension of type dNSName is
> present, that MUST
> > be used as the identity. Otherwise, the (most specific)
> Common Name
> >
> >
> >
> > Rescorla
> > [Page 4]
> > Internet-Draft HTTP Over TLS
> >
> >
> > field in the Subject field of the certificate MUST be
> > used. Although
> > the use of the Common Name is existing practice, it is
> > deprecated and
> > Certification Authorities are encouraged to use the
> > dNSName instead.
> >
> > Matching is performed using the matching rules specified
> by [PKIX].
> > If more than one identity of a given type is present in
> > the certifi-
> > cate (e.g. more than one dNSName name, a match in any one
> > of the set
> > is considered acceptable.) Names may contain the wildcard
> > character *
> > which is considered to match any single domain name
> > component or com-
> > ponent fragment. E.g. *.a.com matches foo.a.com but not
> > bar.foo.a.com. f*.com matches foo.com but not bar.com.
> >
> > If the hostname does not match the identity in the
> > certificate, user
> > oriented clients MUST either notify the user (clients
> MAY give the
> > user the opportunity to continue with the connection in
> > any case) or
> > terminate the connection with a bad certificate error. Automated
> > clients MUST log the error to an appropriate audit log (if
> > available)
> > and SHOULD terminate the connection (with a bad
> certificate error).
> > Automated clients MAY provide a configuration setting
> that disables
> > this check, but MUST provide a setting which enables it.
> >
> > 3.2. Client Identity
> >
> > Typically, the server has no external knowledge of what
> > the client's
> > identity ought to be and so checks (other than that the
> > client has a
> > certificate chain rooted in an appropriate CA) are not
> > possible. If a
> > server has such knowledge (typically from some source external to
> > HTTP or TLS) it SHOULD check the identity as described above.
> >
> >
> >
> >
> >
> >
> >
> >
> >
> >
> >
> >
> >
> >
> >
> >
> >
> >
> >
> >
> >
> >
> >
> > Rescorla
> > [Page 5]
> > Internet-Draft HTTP Over TLS
> >
> >
> > References
> > [PKIX] R. Housley, W. Ford, W. Polk, D. Solo, Internet Public Key
> > Infrastructure: Part I: X.509 Certificate and CRL Profile,
> > <draft-ietf-pkix-ipki-part1-06.txt>, October 1997.
> >
> > [RFC2068] Fielding, R., Gettys, J., Mogul, J., Frystyk, H.,
> > Berners-Lee, T., "Hypertext Transfer Protocol -- HTTP/1.1"
> > RFC 2068, January 1997.
> >
> > [RFC2119] Bradner, S., "Key Words for use in RFCs to indicate
> > Requirement Levels", RFC2119, March 1997.
> >
> > [TLS] Dierks, T., Allen, C., "The TLS Protocol", RFCXXXX,
> > November 1997.
> >
> > Security Considerations
> >
> > This entire document is about security.
> >
> > Author's Address
> >
> > Eric Rescorla <ekr@terisa.com>
> > Terisa Systems, Inc.
> > 4984 El Camino Real
> > Los Altos, CA 94022
> > Phone: (650) 919-1753
> >
> >
> >
> >
> >
> >
> >
> >
> >
> >
> >
> >
> >
> >
> >
> >
> >
> >
> >
> >
> >
> >
> >
> >
> >
> >
> > Rescorla
> > [Page 6]
> > Internet-Draft HTTP Over TLS
> >
> >
> >
> >
> >
> > Table of Contents
> >
> >
> >
> >
> > 1. Introduction
> > ................................................... 1
> >
> > 1.1. Discussion of this Draft
> > ..................................... 1
> >
> > 1.2. Requirements Terminology
> > ..................................... 2
> >
> > 2. HTTP Over TLS
> > .................................................. 2
> >
> > 2.1. Connection Initiation
> > ........................................ 2
> >
> > 2.2. Connection Closure
> > ........................................... 2
> >
> > 2.2.1. Client Behavior
> > ............................................ 3
> >
> > 2.2.2. Server Behavior
> > ............................................ 3
> >
> > 2.3. Port Number
> > .................................................. 4
> >
> > 2.4. URI Format
> > ................................................... 4
> >
> > 3. Endpoint Identification
> > ........................................ 4
> >
> > 3.1. Server Identity
> > .............................................. 4
> >
> > RN Client Identity
> > ................................................ 5
> >
> > References
> > ........................................................ 6
> >
> > Security Considerations
> > ........................................... 6
> >
> > Author's Address
> > .................................................. 6
> >
> >
> >
> >
> >
> >
> >
> >
> >
> >
> >
> > ---
> > You are currently subscribed to ietf-tls as:
> > [rodney@unitran.com]
> > To unsubscribe, forward this message to
> > leave-ietf-tls-812E@lists.consensus.com
> >
>
> ---
> You are currently subscribed to ietf-tls as:
> [rodney@unitran.com]
> To unsubscribe, forward this message to
> leave-ietf-tls-812E@lists.consensus.com
>

---
You are currently subscribed to ietf-tls as: [rodney@unitran.com]
To unsubscribe, forward this message to
leave-ietf-tls-812E@lists.consensus.com